Stress and dietary behaviour among first-year university students in Australia: sex differences.

PubMed

Papier, Keren; Ahmed, Faruk; Lee, Patricia; Wiseman, Juliet

2015-02-01

The aim of this study was to examine the relationship between stress and food selection patterns by sex among first-year undergraduate students studying in an Australian university. Participating in this cross-sectional study were 728 (331 men and 397 female students) first-year students, ages >18 y, attending the Gold Coast Campus of Griffith University. Data were collected using a self-administered questionnaire consisting of three sections: sociodemographic information, stress measures, and a 7-d food frequency questionnaire. More than half (52.9%) of the participants were found to suffer from some level of stress, with relatively more female students (57.4%) suffering than men (47.4%). Men who experienced mild to moderate levels of stress were two to three times more likely to eat cereal foods (P < 0.01), fish/seafood (P < 0.001), and protein powder (P < 0.05). They also tended to eat more meat alternatives (P < 0.05), highly processed foods (P < 0.05), and to drink more alcohol (P < 0.05) than unstressed male students. However, they were less likely to consume vegetables and fruit (P < 0.05) compared with their unstressed counterparts. The trend analysis results indicated significant dose-response patterns in the relationship between stress level and consumption of cereal food, meat alternatives, vegetables and fruit (negative trend), highly processed food, protein powder, beverages and alcoholic beverages (all P < 0.05). Female students who experienced mild to moderate stress were 2.22 times more likely to eat processed food (P < 0.01) than unstressed female students. Female students who experienced severe stress were less likely to consume meat alternatives (P < 0.05) than their unstressed counterparts. Significant dose-response trends were found in the relationship between stress levels and the consumption of meat alternatives, vegetables and fruit (both negative trends), and processed food (all P < 0.01). These results demonstrate a clear difference in food selection patterns between stressed male and female students, with stress being a more significant predictor of unhealthy food selection among male students. Further research is needed using a qualitative approach to understand how stress and eating behavior are related in university students. Copyright © 2015 Elsevier Inc. All rights reserved.

Fucosylated clusterin in semen promotes the uptake of stress-damaged proteins by dendritic cells via DC-SIGN.

PubMed

Merlotti, A; Dantas, E; Remes Lenicov, F; Ceballos, A; Jancic, C; Varese, A; Rubione, J; Stover, S; Geffner, J; Sabatté, J

2015-07-01

Could seminal plasma clusterin play a role in the uptake of stress-damaged proteins by dendritic cells? Seminal plasma clusterin, but not serum clusterin, promotes the uptake of stress-damaged proteins by dendritic cells via DC-SIGN. Clusterin is one of the major extracellular chaperones. It interacts with a variety of stressed proteins to prevent their aggregation, guiding them for receptor-mediated endocytosis and intracellular degradation. The concentration of clusterin in semen is almost 20-fold higher than that found in serum, raising the question about the role of seminal plasma clusterin in reproduction. No previous studies have analyzed whether seminal plasma clusterin has chaperone activity. We have previously shown that seminal plasma clusterin, but not serum clusterin, expresses an extreme abundance of fucosylated glycans. These motifs enable seminal plasma clusterin to bind DC-SIGN with very high affinity. In vitro experiments were performed to evaluate the ability of seminal plasma clusterin to inhibit the precipitation of stressed proteins, promoting their uptake by dendritic cells via DC-SIGN (a C-type lectin receptor selectively expressed on dendritic cells (DC)). Moreover, the ability of seminal plasma clusterin to modulate the phenotype and function of DCs was also assessed. Clusterin was purified from human semen and human serum. Catalase, bovine serum albumin, glutathione S-transferase, and normal human serum were stressed and the ability of seminal plasma clusterin to prevent the precipitation of these proteins, guiding them to DC-SIGN expressed by DCs, was evaluated using a fluorescence-activated cell sorter (FACS). Endocytosis of stressed proteins was analyzed by confocal microscopy and the ability of seminal plasma clusterin-treated DCs to stimulate the proliferation of CD25+FOXP3+CD4+ T cells was also evaluated by FACS. Seminal plasma clusterin interacts with stressed proteins, inhibits their aggregation (P < 0.01) and efficiently targets them to dendritic cells via DC-SIGN (P < 0.01). DCs efficiently endocytosed clusterin-client complexes and sorted them to degradative compartments involved in antigen processing and presentation. Moreover, we also found that the interaction of seminal plasma clusterin with DC-SIGN did not change the phenotype of DCs, but stimulates their ability to induce the expansion of CD25+FOXP3+CD4+ T lymphocytes (P < 0.05 versus control). All the experiments were performed in vitro; hence the relevance of our observations should be validated in vivo. Our results suggest that by inducing the endocytosis of stress-damaged proteins by DCs via DC-SIGN, seminal plasma clusterin might promote a tolerogenic response to male antigens, thereby contributing to female tolerance to seminal antigens. The present research was supported by the Consejo Nacional de Investigaciones Científicas y Técnicas, the Buenos Aires University School of Medicine, and the Agencia Nacional de Promoción Científica y Tecnológica (Argentina). The authors have no conflicts of interest to declare. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Increased Serum Oxidative Stress Markers in Women with Uterine Leiomyoma

PubMed Central

Santulli, Pietro; Borghese, Bruno; Lemaréchal, Herve; Leconte, Mahaut; Millischer, Anne-Elodie; Batteux, Frédéric

2013-01-01

Background Uterine leiomyomas (fibroids) are the most common gynaecological benign tumors in premenopausal women. Evidences support the role of oxidative stress in the development of uterine leiomyoma. We have analysed oxidative stress markers (thiols, advanced oxidized protein products (AOPP), protein carbonyls and nitrates/nitrites) in preoperative sera from women with histologically proven uterine leiomyoma. Methodology/Principal Findings We conducted a laboratory study in a tertiary-care university hospital. Fifty-nine women with histologically proven uterine leiomyoma and ninety-two leiomyoma-free control women have been enrolled in this study. Complete surgical exploration of the abdominopelvic cavity was performed in each patient. Preoperative serum samples were obtained from all study participants to assay serum thiols, AOPP, protein carbonyls and nitrates/nitrites. Concentrations of serum protein carbonyl groups and AOPP were higher in leiomyoma patients than in the control group (p=0.005 and p<0.001, respectively). By contrast, serum thiol levels were lower in leiomyoma patients (p<0.001). We found positive correlations between serum AOPP concentrations and total fibroids weight (r=0.339; p=0.028), serum AOPP and serum protein carbonyls with duration of infertility (r=0.762; p=0.006 and r=0.683; p=0.021, respectively). Conclusions/Significance This study, for the first time, reveals a significant increase of protein oxidative stress status and reduced antioxidant capacity in sera from women with uterine leiomyoma. PMID:23951284

LSU network hubs integrate abiotic and biotic stress responses via interaction with the superoxide dismutase FSD2.

PubMed

Garcia-Molina, Antoni; Altmann, Melina; Alkofer, Angela; Epple, Petra M; Dangl, Jeffery L; Falter-Braun, Pascal

2017-02-01

In natural environments, plants often experience different stresses simultaneously, and adverse abiotic conditions can weaken the plant immune system. Interactome mapping revealed that the LOW SULPHUR UPREGULATED (LSU) proteins are hubs in an Arabidopsis protein interaction network that are targeted by virulence effectors from evolutionarily diverse pathogens. Here we show that LSU proteins are up-regulated in several abiotic and biotic stress conditions, such as nutrient depletion or salt stress, by both transcriptional and post-translational mechanisms. Interference with LSU expression prevents chloroplastic reactive oxygen species (ROS) production and proper stomatal closure during sulphur stress. We demonstrate that LSU1 interacts with the chloroplastic superoxide dismutase FSD2 and stimulates its enzymatic activity in vivo and in vitro. Pseudomonas syringae virulence effectors interfere with this interaction and preclude re-localization of LSU1 to chloroplasts. We demonstrate that reduced LSU levels cause a moderately enhanced disease susceptibility in plants exposed to abiotic stresses such as nutrient deficiency, high salinity, or heavy metal toxicity, whereas LSU1 overexpression confers significant disease resistance in several of these conditions. Our data suggest that the network hub LSU1 plays an important role in co-ordinating plant immune responses across a spectrum of abiotic stress conditions. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Involvement of polyphosphate kinase in virulence and stress tolerance of uropathogenic Proteus mirabilis.

PubMed

Peng, Liang; Jiang, Qiao; Pan, Jia-Yun; Deng, Cong; Yu, Jing-Yi; Wu, Xiao-Man; Huang, Sheng-He; Deng, Xiao-Yan

2016-04-01

Proteus mirabilis (P. mirabilis), a gram-negative enteric bacterium, frequently causes urinary tract infections. Many virulence factors of uropathogenic P. mirabilis have been identified, including urease, flagella, hemolysin and fimbriae. However, the functions of polyphosphate kinase (PPK), which are related to the pathogenicity of many bacteria, remain entirely unknown in P. mirabilis. In this study, a ppk gene encoding the PPK insertional mutant in P. mirabilis strain HI4320 was constructed, and its biological functions were examined. The results of survival studies demonstrated that the ppk mutant was deficient in resistance to oxidative, hyperosmotic and heat stress. The swarming and biofilm formation abilities of P. mirabilis were also attenuated after the ppk interruption. In vitro and in vivo experiments suggested that ppk was required for P. mirabilis to invade the bladder. The negative phenotypes of the ppk mutant could be restored by ppk gene complementation. Furthermore, two-dimensional gel electrophoresis and liquid chromatography-mass spectrometry were used to analyze the proteomes of the wild-type strain and the ppk mutant. Compared with the wild-type strain, seven proteins including TonB-dependent receptor, universal stress protein G, major mannose-resistant/Proteus-like fimbrial protein (MR/P fimbriae), heat shock protein, flagellar capping protein, putative membrane protein and multidrug efflux protein were down-regulated, and four proteins including exported peptidase, repressor protein for FtsI, FKBP-type peptidyl-prolyl cis-trans isomerase and phosphotransferase were up-regulated in the ppk mutant. As a whole, these results indicate that PPK is an important regulator and plays a crucial role in stress tolerance and virulence in uropathogenic P. mirabilis.

The Pepper WPP Domain Protein, CaWDP1, Acts as a Novel Negative Regulator of Drought Stress via ABA Signaling.

PubMed

Park, Chanmi; Lim, Chae Woo; Baek, Woonhee; Kim, Jung-Hyun; Lim, Sohee; Kim, Sang Hyon; Kim, Kyung-Nam; Lee, Sung Chul

2017-04-01

Plants are constantly challenged by various environmental stresses, including high salinity and drought, and they have evolved defense mechanisms to counteract the deleterious effects of these stresses. The plant hormone ABA regulates plant growth and developmental processes and mediates abiotic stress responses. Here, we report the identification and characterization of a novel CaWDP1 (Capsicum annuum) protein. The expression of CaWDP1 in pepper leaves was induced by ABA, drought and NaCl treatments, suggesting its role in the abiotic stress response. CaWDP1 proteins show conserved sequence homology with other known WDP1 proteins, and they are localized in the nucleus and cytoplasm. We generated CaWDP1-silenced peppers via virus-induced gene silencing (VIGS). We evaluated the responses of these CaWDP1-silenced pepper plants and CaWDP1-overexpressing (OX) transgenic Arabidopsis plants to ABA and drought. CaWDP1-silenced pepper plants displayed enhanced tolerance to drought stress, and this was characterized by low levels of leaf water loss in the drought-treated leaves. In contrast to CaWDP1-silenced plants, CaWDP1-OX plants exhibited an ABA-hyposensitive and drought-susceptible phenotype, which was accompanied by high levels of leaf water loss, low leaf temperatures, increased stomatal pore size and low expression levels of stress-responsive genes. Our results indicate that CaWDP1, a novel pepper negative regulator of ABA, regulates the ABA-mediated defense response to drought stress. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Tau Deletion Prevents Stress-Induced Dendritic Atrophy in Prefrontal Cortex: Role of Synaptic Mitochondria.

PubMed

Lopes, Sofia; Teplytska, Larysa; Vaz-Silva, Joao; Dioli, Chrysoula; Trindade, Rita; Morais, Monica; Webhofer, Christian; Maccarrone, Giuseppina; Almeida, Osborne F X; Turck, Christoph W; Sousa, Nuno; Sotiropoulos, Ioannis; Filiou, Michaela D

2017-04-01

Tau protein in dendrites and synapses has been recently implicated in synaptic degeneration and neuronal malfunction. Chronic stress, a well-known inducer of neuronal/synaptic atrophy, triggers hyperphosphorylation of Tau protein and cognitive deficits. However, the cause-effect relationship between these events remains to be established. To test the involvement of Tau in stress-induced impairments of cognition, we investigated the impact of stress on cognitive behavior, neuronal structure, and the synaptic proteome in the prefrontal cortex (PFC) of Tau knock-out (Tau-KO) and wild-type (WT) mice. Whereas exposure to chronic stress resulted in atrophy of apical dendrites and spine loss in PFC neurons as well as significant impairments in working memory in WT mice, such changes were absent in Tau-KO animals. Quantitative proteomic analysis of PFC synaptosomal fractions, combined with transmission electron microscopy analysis, suggested a prominent role for mitochondria in the regulation of the effects of stress. Specifically, chronically stressed animals exhibit Tau-dependent alterations in the levels of proteins involved in mitochondrial transport and oxidative phosphorylation as well as in the synaptic localization of mitochondria in PFC. These findings provide evidence for a causal role of Tau in mediating stress-elicited neuronal atrophy and cognitive impairment and indicate that Tau may exert its effects through synaptic mitochondria. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

The nitrative and oxidative stress in blood platelets isolated from breast cancer patients: the protectory action of aronia melanocarpa extract.

PubMed

Kedzierska, Magdalena; Olas, Beata; Wachowicz, Barbara; Stochmal, Anna; Oleszek, Wieslaw; Jeziorski, Arkadiusz; Piekarski, Janusz

2010-01-01

Since mechanisms involved in the relationship between oxidative stress and breast cancer are still unclear, the aim of our present study was to evaluate oxidative/nitrative modifications of blood platelet proteins by measuring the level of biomarkers of oxidative/nitrative stress such as carbonyl groups, thiol groups and 3-nitrotyrosine in proteins in patients with benign breast diseases and in patients with invasive breast cancer, and compare with the control group. Levels of carbonyl groups and 3-nitrotyrosine residues in platelet proteins were measured by ELISA and a competition ELISA, respectively. The method with 5,5′-dithio-bis(2-nitro-benzoic acid) has been used to analyse free thiol groups in platelet proteins. Patients were hospitalized in the Department of Oncological Surgery, Medical University of Lodz, Poland. Exogenous antioxidants reduce oxidative stress, therefore we also investigated in a model system in vitro the effects of a polyphenol rich extract of Aronia melanocarpa (Rosaceae, final concentration of 50 µg/ml, 5 min, 37°C) on modified blood platelet proteins as well from patients with breast cancer and from the healthy group. We demonstrated in platelet proteins from patients with invasive breast cancer a higher level of carbonyl groups than in the control healthy group (p < 0.02). The level of 3-nitrotyrosine in platelet proteins from patients with invasive breast cancer was also significantly higher than in the healthy subject group (p < 0.001). In contrast, the amount of thiol groups in platelet proteins from patients was significantly lower (about < 50%) than in control blood platelets. In a model system in vitro we also observed that the extract from berries of A. melanocarpa (50 µg/ml, 5 min, 37°C) due to antioxidant action, significantly reduced the oxidative/nitrative stress (measured by thiol groups and 3-nitrotyrosine) in platelets, not only from the healthy group, but also from patients with benign breast diseases and in patients with invasive breast cancer.

A tomato chloroplast-targeted DnaJ protein protects Rubisco activity under heat stress.

PubMed

Wang, Guodong; Kong, Fanying; Zhang, Song; Meng, Xia; Wang, Yong; Meng, Qingwei

2015-06-01

Photosynthesis is one of the biological processes most sensitive to heat stress in plants. Carbon assimilation, which depends on ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), is one of the major sites sensitive to heat stress in photosynthesis. In this study, the roles of a tomato (Solanum lycopersicum) chloroplast-targeted DnaJ protein (SlCDJ2) in resisting heat using sense and antisense transgenic tomatoes were examined. SlCDJ2 was found to be uniformly distributed in the thylakoids and stroma of the chloroplasts. Under heat stress, sense plants exhibited higher chlorophyll contents and fresh weights, and lower accumulation of reactive oxygen species (ROS) and membrane damage. Moreover, Rubisco activity, Rubisco large subunit (RbcL) content, and CO2 assimilation capacity were all higher in sense plants and lower in antisense plants compared with wild-type plants. Thus, SlCDJ2 contributes to maintenance of CO2 assimilation capacity mainly by protecting Rubisco activity under heat stress. SlCDJ2 probably achieves this by keeping the levels of proteolytic enzymes low, which prevents accelerated degradation of Rubisco under heat stress. Furthermore, a chloroplast heat-shock protein 70 was identified as a binding partner of SlCDJ2 in yeast two-hybrid assays. Taken together, these findings establish a role for SlCDJ2 in maintaining Rubisco activity in plants under heat stress. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Cranberry interacts with dietary macronutrients to promote healthy aging in Drosophila.

PubMed

Wang, Cecilia; Yolitz, Jason; Alberico, Thomas; Laslo, Mara; Sun, Yaning; Wheeler, Charles T; Sun, Xiaoping; Zou, Sige

2014-08-01

Botanicals possess numerous bioactivities, and some promote healthy aging. Dietary macronutrients are major determinants of life span. The interaction between botanicals and macronutrients that modulates life span is not well understood. Here, we investigated the effect of a cranberry-containing botanical on life span and the influence of macronutrients on the longevity-related effect of cranberry in Drosophila. Flies were supplemented with cranberry on three dietary conditions: standard, high sugar-low protein, and low sugar-high protein diets. We found that cranberry slightly extended life span in males fed with the low sugar-high protein diet but not with other diets. Cranberry extended life span in females fed with the standard diet and more prominently the high sugar-low protein diet but not with the low sugar-high protein diet. Life-span extension was associated with increased reproduction and higher expression of oxidative stress and heat shock response genes. Moreover, cranberry improved survival of sod1 knockdown and dfoxo mutant flies but did not increase wild-type fly's resistance to acute oxidative stress. Cranberry slightly extended life span in flies fed with a high-fat diet. These findings suggest that cranberry promotes healthy aging by increasing stress responsiveness. Our study reveals an interaction of cranberry with dietary macronutrients and stresses the importance of considering diet composition in designing interventions for promoting healthy aging. Published by Oxford University Press on behalf of the Gerontological Society of America 2013.

Salt-induced subcellular kinase relocation and seedling susceptibility caused by overexpression of Medicago SIMKK in Arabidopsis.

PubMed

Ovečka, Miroslav; Takáč, Tomáš; Komis, George; Vadovič, Pavol; Bekešová, Slávka; Doskočilová, Anna; Šamajová, Veronika; Luptovčiak, Ivan; Samajová, Olga; Schweighofer, Alois; Meskiene, Irute; Jonak, Claudia; Křenek, Pavel; Lichtscheidl, Irene; Škultéty, L'udovít; Hirt, Heribert; Šamaj, Jozef

2014-06-01

Dual-specificity mitogen-activated protein kinases kinases (MAPKKs) are the immediate upstream activators of MAPKs. They simultaneously phosphorylate the TXY motif within the activation loop of MAPKs, allowing them to interact with and regulate multiple substrates. Often, the activation of MAPKs triggers their nuclear translocation. However, the spatiotemporal dynamics and the physiological consequences of the activation of MAPKs, particularly in plants, are still poorly understood. Here, we studied the activation and localization of the Medicago sativa stress-induced MAPKK (SIMKK)-SIMK module after salt stress. In the inactive state, SIMKK and SIMK co-localized in the cytoplasm and in the nucleus. Upon salt stress, however, a substantial part of the nuclear pool of both SIMKK and SIMK relocated to cytoplasmic compartments. The course of nucleocytoplasmic shuttling of SIMK correlated temporally with the dual phosphorylation of the pTEpY motif. SIMKK function was further studied in Arabidopsis plants overexpressing SIMKK-yellow fluorescent protein (YFP) fusions. SIMKK-YFP plants showed enhanced activation of Arabidopsis MPK3 and MPK6 kinases upon salt treatment and exhibited high sensitivity against salt stress at the seedling stage, although they were salt insensitive during seed germination. Proteomic analysis of SIMKK-YFP overexpressors indicated the differential regulation of proteins directly or indirectly involved in salt stress responses. These proteins included catalase, peroxiredoxin, glutathione S-transferase, nucleoside diphosphate kinase 1, endoplasmic reticulum luminal-binding protein 2, and finally plasma membrane aquaporins. In conclusion, Arabidopsis seedlings overexpressing SIMKK-YFP exhibited higher salt sensitivity consistent with their proteome composition and with the presumptive MPK3/MPK6 hijacking of the salt response pathway. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Thermal Preference Ranges Correlate with Stable Signals of Universal Stress Markers in Lake Baikal Endemic and Holarctic Amphipods

PubMed Central

Axenov-Gribanov, Denis; Bedulina, Daria; Shatilina, Zhanna; Jakob, Lena; Vereshchagina, Kseniya; Lubyaga, Yulia; Gurkov, Anton; Shchapova, Ekaterina; Luckenbach, Till; Lucassen, Magnus; Sartoris, Franz Josef; Pörtner, Hans-Otto; Timofeyev, Maxim

2016-01-01

Temperature is the most pervasive abiotic environmental factor for aquatic organisms. Fluctuations in temperature range lead to changes in metabolic performance. Here, we aimed to identify whether surpassing the thermal preference zones is correlated with shifts in universal cellular stress markers of protein integrity, responses to oxidative stress and lactate content, as indicators of anaerobic metabolism. Exposure of the Lake Baikal endemic amphipod species Eulimnogammarus verrucosus (Gerstfeldt, 1858), Ommatogammarus flavus (Dybowski, 1874) and of the Holarctic amphipod Gammarus lacustris Sars 1863 (Amphipoda, Crustacea) to increasing temperatures resulted in elevated heat shock protein 70 (Hsp70) and lactate content, elevated antioxidant enzyme activities (i.e., catalase and peroxidase), and reduced lactate dehydrogenase and glutathione S-transferase activities. Thus, the zone of stability (absence of any significant changes) of the studied molecular and biochemical markers correlated with the behaviorally preferred temperatures. We conclude that the thermal behavioral responses of the studied amphipods are directly related to metabolic processes at the cellular level. Thus, the determined thermal ranges may possibly correspond to the thermal optima. This relationship between species-specific behavioral reactions and stress response metabolism may have significant ecological consequences that result in a thermal zone-specific distribution (i.e., depths, feed spectrum, etc.) of species. As a consequence, by separating species with different temperature preferences, interspecific competition is reduced, which, in turn, increases a species’ Darwinian fitness in its environment. PMID:27706227

Comparative Phosphoproteomics Reveals an Important Role of MKK2 in Banana (Musa spp.) Cold Signal Network

PubMed Central

Gao, Jie; Zhang, Sheng; He, Wei-Di; Shao, Xiu-Hong; Li, Chun-Yu; Wei, Yue-Rong; Deng, Gui-Ming; Kuang, Rui-Bin; Hu, Chun-Hua; Yi, Gan-Jun; Yang, Qiao-Song

2017-01-01

Low temperature is one of the key environmental stresses, which greatly affects global banana production. However, little is known about the global phosphoproteomes in Musa spp. and their regulatory roles in response to cold stress. In this study, we conducted a comparative phosphoproteomic profiling of cold-sensitive Cavendish Banana and relatively cold tolerant Dajiao under cold stress. Phosphopeptide abundances of five phosphoproteins involved in MKK2 interaction network, including MKK2, HY5, CaSR, STN7 and kinesin-like protein, show a remarkable difference between Cavendish Banana and Dajiao in response to cold stress. Western blotting of MKK2 protein and its T31 phosphorylated peptide verified the phosphoproteomic results of increased T31 phosphopeptide abundance with decreased MKK2 abundance in Daojiao for a time course of cold stress. Meanwhile increased expression of MKK2 with no detectable T31 phosphorylation was found in Cavendish Banana. These results suggest that the MKK2 pathway in Dajiao, along with other cold-specific phosphoproteins, appears to be associated with the molecular mechanisms of high tolerance to cold stress in Dajiao. The results also provide new evidence that the signaling pathway of cellular MKK2 phosphorylation plays an important role in abiotic stress tolerance that likely serves as a universal plant cold tolerance mechanism. PMID:28106078

GEM2Net: from gene expression modeling to -omics networks, a new CATdb module to investigate Arabidopsis thaliana genes involved in stress response.

PubMed

Zaag, Rim; Tamby, Jean Philippe; Guichard, Cécile; Tariq, Zakia; Rigaill, Guillem; Delannoy, Etienne; Renou, Jean-Pierre; Balzergue, Sandrine; Mary-Huard, Tristan; Aubourg, Sébastien; Martin-Magniette, Marie-Laure; Brunaud, Véronique

2015-01-01

CATdb (http://urgv.evry.inra.fr/CATdb) is a database providing a public access to a large collection of transcriptomic data, mainly for Arabidopsis but also for other plants. This resource has the rare advantage to contain several thousands of microarray experiments obtained with the same technical protocol and analyzed by the same statistical pipelines. In this paper, we present GEM2Net, a new module of CATdb that takes advantage of this homogeneous dataset to mine co-expression units and decipher Arabidopsis gene functions. GEM2Net explores 387 stress conditions organized into 18 biotic and abiotic stress categories. For each one, a model-based clustering is applied on expression differences to identify clusters of co-expressed genes. To characterize functions associated with these clusters, various resources are analyzed and integrated: Gene Ontology, subcellular localization of proteins, Hormone Families, Transcription Factor Families and a refined stress-related gene list associated to publications. Exploiting protein-protein interactions and transcription factors-targets interactions enables to display gene networks. GEM2Net presents the analysis of the 18 stress categories, in which 17,264 genes are involved and organized within 681 co-expression clusters. The meta-data analyses were stored and organized to compose a dynamic Web resource. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

GSK3β and VDAC Involvement in ER Stress and Apoptosis Modulation during Orthotopic Liver Transplantation

PubMed Central

Zaouali, Mohamed Amine; Panisello, Arnau; Lopez, Alexandre; Castro, Carlos; Folch, Emma; Carbonell, Teresa; Rolo, Anabela; Palmeira, Carlos Marques; Garcia-Gil, Agustin; Adam, René; Roselló-Catafau, Joan

2017-01-01

We investigated the involvement of glycogen synthase kinase-3β (GSK3β) and the voltage-dependent anion channel (VDAC) in livers subjected to cold ischemia–reperfusion injury (I/R) associated with orthotopic liver transplantation (OLT). Rat livers were preserved in University of Wisconsin (UW) and Institute Georges Lopez (IGL-1) solution, the latter enriched or not with trimetazidine, and then subjected to OLT. Transaminase (ALT) and HMGB1 protein levels, glutamate dehydrogenase (GLDH), and oxidative stress (MDA) were measured. The AKT protein kinase and its direct substrates, GSK3β and VDAC, as well as caspases 3, 9, and cytochrome C and reticulum endoplasmic stress-related proteins (GRP78, pPERK, ATF4, and CHOP), were determined by Western blot. IGL-1+TMZ significantly reduced liver injury. We also observed a significant phosphorylation of AKT, which in turn induced the phosphorylation and inhibition of GSK3β. In addition, TMZ protected the mitochondria since, in comparison with IGL-1 alone, we found reductions in VDAC phosphorylation, apoptosis, and GLDH release. All these results were correlated with decreased ER stress. Addition of TMZ to IGL-1 solution increased the tolerance of the liver graft to I/R injury through inhibition of GSK3β and VDAC, contributing to ER stress reduction and cell death prevention. PMID:28282906

Oxidative stress during extracorporeal circulation.

PubMed

McDonald, Charles Ian; Fraser, John Francis; Coombes, Jeff S; Fung, Yoke Lin

2014-12-01

There is an increased oxidative stress response in patients having cardiac surgery, haemodialysis or extracorporeal membrane oxygenation that is related to poorer outcomes and increased mortality. Exposure of the patients' blood to the artificial surfaces of these extracorporeal devices, coupled with inflammatory responses, hyperoxia and the pathophysiological aspects of the underlying illness itself, all contribute to this oxidative stress response. Oxidative stress occurs when there is a disruption of redox signalling and loss of control of redox balance. Ongoing oxidative stress occurring during extracorporeal circulation (ECC) results in damage to lipids, proteins and DNA and contributes to morbidity and mortality. This review discusses reactive species generation and the potential clinical consequences of oxidative stress during ECC as well as provides an overview of some current antioxidant compounds that are available to potentially mitigate the oxidative stress response. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Endoplasmic reticulum stress increases AT1R mRNA expression via TIA-1-dependent mechanism.

PubMed

Backlund, Michael; Paukku, Kirsi; Kontula, Kimmo K; Lehtonen, Jukka Y A

2016-04-20

As the formation of ribonucleoprotein complexes is a major mechanism of angiotensin II type 1 receptor (AT1R) regulation, we sought to identify novel AT1R mRNA binding proteins. By affinity purification and mass spectroscopy, we identified TIA-1. This interaction was confirmed by colocalization of AT1R mRNA and TIA-1 by FISH and immunofluorescence microscopy. In immunoprecipitates of endogenous TIA- 1, reverse transcription-PCR amplified AT1R mRNA. TIA-1 has two binding sites within AT1R 3'-UTR. The binding site proximal to the coding region is glyceraldehyde-3-phosphate dehydrogenase (GAPDH)-dependent whereas the distal binding site is not. TIA-1 functions as a part of endoplasmic reticulum (ER) stress response leading to stress granule (SG) formation and translational silencing. We and others have shown that AT1R expression is increased by ER stress-inducing factors. In unstressed cells, TIA-1 binds to AT1R mRNA and decreases AT1R protein expression. Fluorescence microscopy shows that ER stress induced by thapsigargin leads to the transfer of TIA-1 to SGs. In FISH analysis AT1R mRNA remains in the cytoplasm and no longer colocalizes with TIA-1. Thus, release of TIA-1-mediated suppression by ER stress increases AT1R protein expression. In conclusion, AT1R mRNA is regulated by TIA-1 in a ER stress-dependent manner. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

REST and stress resistance in ageing and Alzheimer's disease

NASA Astrophysics Data System (ADS)

Lu, Tao; Aron, Liviu; Zullo, Joseph; Pan, Ying; Kim, Haeyoung; Chen, Yiwen; Yang, Tun-Hsiang; Kim, Hyun-Min; Drake, Derek; Liu, X. Shirley; Bennett, David A.; Colaiácovo, Monica P.; Yankner, Bruce A.

2014-03-01

Human neurons are functional over an entire lifetime, yet the mechanisms that preserve function and protect against neurodegeneration during ageing are unknown. Here we show that induction of the repressor element 1-silencing transcription factor (REST; also known as neuron-restrictive silencer factor, NRSF) is a universal feature of normal ageing in human cortical and hippocampal neurons. REST is lost, however, in mild cognitive impairment and Alzheimer's disease. Chromatin immunoprecipitation with deep sequencing and expression analysis show that REST represses genes that promote cell death and Alzheimer's disease pathology, and induces the expression of stress response genes. Moreover, REST potently protects neurons from oxidative stress and amyloid β-protein toxicity, and conditional deletion of REST in the mouse brain leads to age-related neurodegeneration. A functional orthologue of REST, Caenorhabditis elegans SPR-4, also protects against oxidative stress and amyloid β-protein toxicity. During normal ageing, REST is induced in part by cell non-autonomous Wnt signalling. However, in Alzheimer's disease, frontotemporal dementia and dementia with Lewy bodies, REST is lost from the nucleus and appears in autophagosomes together with pathological misfolded proteins. Finally, REST levels during ageing are closely correlated with cognitive preservation and longevity. Thus, the activation state of REST may distinguish neuroprotection from neurodegeneration in the ageing brain.

Genome-wide identification and characterization of the Populus WRKY transcription factor family and analysis of their expression in response to biotic and abiotic stresses.

PubMed

Jiang, Yuanzhong; Duan, Yanjiao; Yin, Jia; Ye, Shenglong; Zhu, Jingru; Zhang, Faqi; Lu, Wanxiang; Fan, Di; Luo, Keming

2014-12-01

WRKY proteins are a large family of regulators involved in various developmental and physiological processes, especially in coping with diverse biotic and abiotic stresses. In this study, 100 putative PtrWRKY genes encoded the proteins contained in the complete WRKY domain in Populus. Phylogenetic analysis revealed that the members of this superfamily among poplar, Arabidopsis, and other species were divided into three groups with several subgroups based on the structures of the WRKY protein sequences. Various cis-acting elements related to stress and defence responses were found in the promoter regions of PtrWRKY genes by promoter analysis. High-throughput transcriptomic analyses identified that 61 of the PtrWRKY genes were induced by biotic and abiotic treatments, such as Marssonina brunnea, salicylic acid (SA), methyl jasmonate (MeJA), wounding, cold, and salinity. Among these PtrWRKY genes, transcripts of 46 selected genes were observed in different tissues, including roots, stems, and leaves. Quantitative RT-PCR analysis further confirmed the induced expression of 18 PtrWRKY genes by one or more stress treatments. The overexpression of an SA-inducible gene, PtrWRKY89, accelerated expression of PR protein genes and improved resistance to pathogens in transgenic poplar, suggesting that PtrWRKY89 is a regulator of an SA-dependent defence-signalling pathway in poplar. Taken together, our results provided significant information for improving the resistance and stress tolerance of woody plants. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Aureolib — A Proteome Signature Library: Towards an Understanding of Staphylococcus aureus Pathophysiology

PubMed Central

Pané-Farré, Jan; Kusch, Harald; Wolf, Carmen; Reiß, Swantje; Binh, Le Thi Nguyen; Albrecht, Dirk; Riedel, Katharina; Hecker, Michael; Engelmann, Susanne

2013-01-01

Gel-based proteomics is a powerful approach to study the physiology of Staphylococcus aureus under various growth restricting conditions. We analyzed 679 protein spots from a reference 2-dimensional gel of cytosolic proteins of S. aureus COL by mass spectrometry resulting in 521 different proteins. 4,692 time dependent protein synthesis profiles were generated by exposing S. aureus to nine infection-related stress and starvation stimuli (H2O2, diamide, paraquat, NO, fermentation, nitrate respiration, heat shock, puromycin, mupirocin). These expression profiles are stored in an online resource called Aureolib (http://www.aureolib.de). Moreover, information on target genes of 75 regulators and regulatory elements were included in the database. Cross-comparisons of this extensive data collection of protein synthesis profiles using the tools implemented in Aureolib lead to the identification of stress and starvation specific marker proteins. Altogether, 226 protein synthesis profiles showed induction ratios of 2.5-fold or higher under at least one of the tested conditions with 157 protein synthesis profiles specifically induced in response to a single stimulus. The respective proteins might serve as marker proteins for the corresponding stimulus. By contrast, proteins whose synthesis was increased or repressed in response to more than four stimuli are rather exceptional. The only protein that was induced by six stimuli is the universal stress protein SACOL1759. Most strikingly, cluster analyses of synthesis profiles of proteins differentially synthesized under at least one condition revealed only in rare cases a grouping that correlated with known regulon structures. The most prominent examples are the GapR, Rex, and CtsR regulon. In contrast, protein synthesis profiles of proteins belonging to the CodY and σB regulon are widely distributed. In summary, Aureolib is by far the most comprehensive protein expression database for S. aureus and provides an essential tool to decipher more complex adaptation processes in S. aureus during host pathogen interaction. PMID:23967085

Response of Escherichia coli to Prolonged Berberine Exposure.

PubMed

Budeyri Gokgoz, Nilay; Avci, Fatma Gizem; Yoneten, Kubra Karaosmanoglu; Alaybeyoglu, Begum; Ozkirimli, Elif; Sayar, Nihat Alpagu; Kazan, Dilek; Sariyar Akbulut, Berna

2017-07-01

Berberine is a plant-derived alkaloid possessing antimicrobial activity; unfortunately, its efflux through multidrug resistance pumps reduces its efficacy. Cellular life span of Escherichia coli is generally shorter with prolonged berberine exposure; nevertheless, about 30% of the cells still remain robust following this treatment. To elucidate its mechanism of action and to identify proteins that could be involved in development of antimicrobial resistance, protein profiles of E. coli cells treated with berberine for 4.5 and 8 hours were compared with control cells. A total of 42 proteins were differentially expressed in cells treated with berberine for 8 hours when compared to control cells. In both 4.5 and 8 hours of berberine-treated cells, carbohydrate and peptide uptake regimens remained unchanged, although amino acid maintenance regimen switched from transport to synthesis. Defect in cell division persisted and this condition was confirmed by images obtained from scanning electron microscopy. Universal stress proteins were not involved in stress response. The significant increase in the abundance of elongation factors could suggest the involvement of these proteins in protection by exhibiting chaperone activities. Furthermore, the involvement of the outer membrane protein OmpW could receive special attention as a protein involved in response to antimicrobial agents, since the expression of only this porin protein was upregulated after 8 hours of exposure.

Rice G-protein subunits qPE9-1 and RGB1 play distinct roles in abscisic acid responses and drought adaptation.

PubMed

Zhang, Dong-Ping; Zhou, Yong; Yin, Jian-Feng; Yan, Xue-Jiao; Lin, Sheng; Xu, Wei-Feng; Baluška, František; Wang, Yi-Ping; Xia, Yi-Ji; Liang, Guo-hua; Liang, Jian-Sheng

2015-10-01

Heterotrimeric GTP-binding protein (G-protein)-mediated abscisic acid (ABA) and drought-stress responses have been documented in numerous plant species. However, our understanding of the function of rice G-protein subunits in ABA signalling and drought tolerance is limited. In this study, the function of G-protein subunits in ABA response and drought resistance in rice plants was explored. It was found that the transcription level of qPE9-1 (rice Gγ subunit) gradually decreased with increasing ABA concentration and the lack of qPE9-1 showed an enhanced drought tolerance in rice plants. In contrast, mRNA levels of RGB1 (rice Gβ subunit) were significantly upregulated by ABA treatment and the lack of RGB1 led to reduced drought tolerance. Furthermore, the results suggested that qPE9-1 negatively regulates the ABA response by suppressing the expression of key transcription factors involved in ABA and stress responses, while RGB1 positively regulates ABA biosynthesis by upregulating NCED gene expression under both normal and drought stress conditions. Taken together, it is proposed that RGB1 is a positive regulator of the ABA response and drought adaption in rice plants, whereas qPE9-1 is modulated by RGB1 and functions as a negative regulator in the ABA-dependent drought-stress responses. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Oxidative Damage in Diabetics: Insights from a Graduate Study in La Reunion University

ERIC Educational Resources Information Center

Girard, Dorothée; Rondeau, Philippe; Catan, Aurélie; Planesse, Cynthia; Giraud, Pierre; Bourdon, Emmanuel

2014-01-01

Due to the growing incidence of diabetes in developed nations, there is a compelling case to be made for teaching graduate students more deeply about mechanisms underlying this disease. Diabetes is associated with enhanced oxidative stress and protein glycation via the covalent binding of glucose molecules. Albumin represents the major plasmatic…

The effect of Fusarium culmorum infection and deoxynivalenol (DON) application on proteome response in barley cultivars Chevron and Pedant.

PubMed

Kosová, Klára; Chrpová, Jana; Šantrůček, Jiří; Hynek, Radovan; Štěrbová, Lenka; Vítámvás, Pavel; Bradová, Jana; Prášil, Ilja Tom

2017-10-03

Fusarium head blight (FHB) disease adversely affects grain quality and final yield in small-grain cereals including barley. In the present study, the effect of an artificial infection with Fusarium culmorum and an application of deoxynivalenol (DON) on barley spikes of cultivars Chevron and Pedant during flowering was investigated at grain mid-dough stage (BBCH 73) 10days after pathogen inoculation (10 dai). Proteomic analysis using a two-dimensional differential gel electrophoresis (2D-DIGE) technique coupled with LC-MS/MS investigated 98 protein spots revealing quantitative or qualitative differences between the experimental variants. Protein functional annotation of 93 identified protein spots revealed that most affected functional groups represent storage proteins (globulins, hordeins), followed by proteins involved in carbohydrate metabolism (α-amylase inhibitor, β-amylase, glycolytic enzymes), amino acid metabolism (aminotransferases), defence response (chitinase, xylanase inhibitor, serpins, SGT1, universal stress protein USP), protein folding (chaperones, chaperonins), redox metabolism (ascorbate-glutathione cycle), and proteasome-dependent protein degradation. The obtained results indicate adverse effects of infection on plant proteome as well as an active plant response to pathogen as shown by enhanced levels of several inhibitors of pathogen-produced degradation enzymes (α-amylase inhibitor, xylanase inhibitor, serpins), chaperones, and other stress-related proteins (SGT1, USP). Genotypic differences were found in hordein abundance between Chevron and Pedant. Copyright © 2017 Elsevier B.V. All rights reserved.

The bromodomain protein BRD4 regulates splicing during heat shock.

PubMed

Hussong, Michelle; Kaehler, Christian; Kerick, Martin; Grimm, Christina; Franz, Alexandra; Timmermann, Bernd; Welzel, Franziska; Isensee, Jörg; Hucho, Tim; Krobitsch, Sylvia; Schweiger, Michal R

2017-01-09

The cellular response to heat stress is an ancient and evolutionarily highly conserved defence mechanism characterised by the transcriptional up-regulation of cyto-protective genes and a partial inhibition of splicing. These features closely resemble the proteotoxic stress response during tumor development. The bromodomain protein BRD4 has been identified as an integral member of the oxidative stress as well as of the inflammatory response, mainly due to its role in the transcriptional regulation process. In addition, there are also several lines of evidence implicating BRD4 in the splicing process. Using RNA-sequencing we found a significant increase in splicing inhibition, in particular intron retentions (IR), following heat treatment in BRD4-depleted cells. This leads to a decrease of mRNA abundancy of the affected transcripts, most likely due to premature termination codons. Subsequent experiments revealed that BRD4 interacts with the heat shock factor 1 (HSF1) such that under heat stress BRD4 is recruited to nuclear stress bodies and non-coding SatIII RNA transcripts are up-regulated. These findings implicate BRD4 as an important regulator of splicing during heat stress. Our data which links BRD4 to the stress induced splicing process may provide novel mechanisms of BRD4 inhibitors in regard to anti-cancer therapies. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Increasing cyclic electron flow is related to Na+ sequestration into vacuoles for salt tolerance in soybean.

PubMed

He, Yi; Fu, Junliang; Yu, Chenliang; Wang, Xiaoman; Jiang, Qinsu; Hong, Jian; Lu, Kaixing; Xue, Gangping; Yan, Chengqi; James, Andrew; Xu, Ligen; Chen, Jianping; Jiang, Dean

2015-11-01

In land plants, the NAD(P)H dehydrogenase (NDH) complex reduces plastoquinones and drives cyclic electron flow (CEF) around PSI. It also produces extra ATP for photosynthesis and improves plant fitness under conditions of abiotic environmental stress. To elucidate the role of CEF in salt tolerance of the photosynthetic apparatus, Na(+) concentration, chlorophyll fluorescence, and expression of NDH B and H subunits, as well as of genes related to cellular and vacuolar Na(+) transport, were monitored. The salt-tolerant Glycine max (soybean) variety S111-9 exhibited much higher CEF activity and ATP accumulation in light than did the salt-sensitive variety Melrose, but similar leaf Na(+) concentrations under salt stress. In S111-9 plants, ndhB and ndhH were highly up-regulated under salt stress and their corresponding proteins were maintained at high levels or increased significantly. Under salt stress, S111-9 plants accumulated Na(+) in the vacuole, but Melrose plants accumulated Na(+) in the chloroplast. Compared with Melrose, S111-9 plants also showed higher expression of some genes associated with Na(+) transport into the vacuole and/or cell, such as genes encoding components of the CBL10 (calcineurin B-like protein 10)-CIPK24 (CBL-interacting protein kinase 24)-NHX (Na(+)/H(+) antiporter) and CBL4 (calcineurin B-like protein 4)-CIPK24-SOS1 (salt overly sensitive 1) complexes. Based on the findings, it is proposed that enhanced NDH-dependent CEF supplies extra ATP used to sequester Na(+) in the vacuole. This reveals an important mechanism for salt tolerance in soybean and provides new insights into plant resistance to salt stress. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Whole-transcriptome response to water stress in a California endemic oak, Quercus lobata.

PubMed

Gugger, Paul F; Peñaloza-Ramírez, Juan Manuel; Wright, Jessica W; Sork, Victoria L

2017-05-01

Reduced water availability during drought can create major stress for many plant species. Within a species, populations with a history of seasonal drought may have evolved the ability to tolerate drought more than those in areas of high precipitation and low seasonality. In this study, we assessed response to water stress in a California oak species, Quercus lobata Née, by measuring changes in gene expression profiles before and after a simulated drought stress treatment through water deprivation of seedlings in a greenhouse setting. Using whole-transcriptome sequencing from nine samples from three collection localities, we identified which genes are involved in response to drought stress and tested the hypothesis that seedlings sampled from climatically different regions of the species range respond to water stress differently. We observed a surprisingly massive transcriptional response to drought: 35,347 of 68,434 contigs (52%) were differentially expressed before versus after drought treatment, of which 18,111 were down-regulated and 17,236 were up-regulated. Genes functionally associated with abiotic stresses and death were enriched among the up-regulated genes, whereas metabolic and cell part-related genes were enriched among the down-regulated. We found 56 contigs that exhibited significantly different expression responses to the drought treatment among the three populations (treatment × population interaction), suggesting that those genes may be involved in local adaptation to drought stress. These genes have stress response (e.g., WRKY DNA-binding protein 51 and HSP20-like chaperones superfamily protein), metabolic (e.g., phosphoglycerate kinase and protein kinase superfamily protein), transport/transfer (e.g., cationic amino acid transporter 7 and K+ transporter) and regulatory functions (e.g., WRKY51 and Homeodomain-like transcriptional regulator). Baseline expression levels of 1310 unique contigs also differed among pairs of populations, and they were enriched for metabolic and cell part-related genes. Out of the large fraction of the transcriptome that was differentially expressed in response to our drought treatment, we identified several novel genes that are candidates for involvement in local adaptation to drought. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effects of cannabidiol interactions with Wnt/β-catenin pathway and PPARγ on oxidative stress and neuroinflammation in Alzheimer's disease.

PubMed

Vallée, Alexandre; Lecarpentier, Yves; Guillevin, Rémy; Vallée, Jean-Noël

2017-10-01

Alzheimer's disease (AD) is a neurodegenerative disease, in which the primary etiology remains unknown. AD presents amyloid beta (Aβ) protein aggregation and neurofibrillary plaque deposits. AD shows oxidative stress and chronic inflammation. In AD, canonical Wingless-Int (Wnt)/β-catenin pathway is downregulated, whereas peroxisome proliferator-activated receptor γ (PPARγ) is increased. Downregulation of Wnt/β-catenin, through activation of glycogen synthase kinase-3β (GSK-3β) by Aβ, and inactivation of phosphatidylinositol 3-kinase/Akt signaling involve oxidative stress in AD. Cannabidiol (CBD) is a non-psychotomimetic phytocannabinoid from Cannabis sativa plant. In PC12 cells, Aβ-induced tau protein hyperphosphorylation is inhibited by CBD. This inhibition is associated with a downregulation of p-GSK-3β, an inhibitor of Wnt pathway. CBD may also increase Wnt/β-catenin by stimulation of PPARγ, inhibition of Aβ and ubiquitination of amyloid precursor protein. CBD attenuates oxidative stress and diminishes mitochondrial dysfunction and reactive oxygen species generation. CBD suppresses, through activation of PPARγ, pro-inflammatory signaling and may be a potential new candidate for AD therapy. © The Author 2017. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The RING Finger E3 Ligase SpRing is a Positive Regulator of Salt Stress Signaling in Salt-Tolerant Wild Tomato Species.

PubMed

Qi, Shilian; Lin, Qingfang; Zhu, Huishan; Gao, Fenghua; Zhang, Wenhao; Hua, Xuejun

2016-03-01

Protein ubiquitination in plants plays critical roles in many biological processes, including adaptation to abiotic stresses. Previously, RING finger E3 ligase has been characterized during salt stress response in several plant species, but little is known about its function in tomato. Here, we report that SpRing, a stress-inducible gene, is involved in salt stress signaling in wild tomato species Solanum pimpinellifolium 'PI365967'. In vitro ubiquitination assay revealed that SpRing is an E3 ubiquitin ligase and the RING finger conserved region is required for its activity. SpRing is expressed in all tissues of wild tomato and up-regulated by salt, drought and osmotic stresses, but repressed by low temperature. Green fluorescent protein (GFP) fusion analysis showed that SpRing is localized at the endoplasmic reticulum. Silencing of SpRing through a virus-induced gene silencing approach led to increased sensitivity to salt stress in wild tomato. Overexpression of SpRing in Arabidopsis thaliana resulted in enhanced salt tolerance during seed germination and early seedling development. The expression levels of certain key stress-related genes are altered both in SpRing-overexpressing Arabidopsis plants and virus-induced gene silenced tomato seedlings. Taken together, our results indicate that SpRing is involved in salt stress and functions as a positive regulator of salt tolerance. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Comparative analyses of universal extraction buffers for assay of stress related biochemical and physiological parameters.

PubMed

Han, Chunyu; Chan, Zhulong; Yang, Fan

2015-01-01

Comparative efficiency of three extraction solutions, including the universal sodium phosphate buffer (USPB), the Tris-HCl buffer (UTHB), and the specific buffers, were compared for assays of soluble protein, free proline, superoxide radical (O2∙-), hydrogen peroxide (H2O2), and the antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (POD), ascorbate peroxidase (APX), glutathione peroxidase (GPX), and glutathione reductase (GR) in Populus deltoide. Significant differences for protein extraction were detected via sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and two-dimensional electrophoresis (2-DE). Between the two universal extraction buffers, the USPB showed higher efficiency for extraction of soluble protein, CAT, GR, O2∙-, GPX, SOD, and free proline, while the UTHB had higher efficiency for extraction of APX, POD, and H2O2. When compared with the specific buffers, the USPB showed higher extraction efficiency for measurement of soluble protein, CAT, GR, and O2∙-, parallel extraction efficiency for GPX, SOD, free proline, and H2O2, and lower extraction efficiency for APX and POD, whereas the UTHB had higher extraction efficiency for measurement of POD and H2O2. Further comparisons proved that 100 mM USPB buffer showed the highest extraction efficiencies. These results indicated that USPB would be suitable and efficient for extraction of soluble protein, CAT, GR, GPX, SOD, H2O2, O2∙-, and free proline.

The Role of Stress Proteins in the Study of Allostatic Overload in Birds: Use and Applicability to Current Studies in Avian Ecology

PubMed Central

Herring, Garth; Gawlik, Dale E.

2007-01-01

Stress proteins offer a measure of stress in birds at the cellular level that are an alternative to the glucocorticoids. Stress proteins are not biased by handling stress, the increase in stress proteins lasts longer than with other measures (e.g., corticosterone), and, therefore, they may be a more appropriate measure of long-term or chronic stress. However, caution should be practiced when using stress proteins because the level of stress needed to elicit a response may be higher than with corticosterone. Stress proteins have only recently been used to measure the response to competition, food limitation, growth, and parasitism in birds. In other taxa, the stress proteins have been used to measure genetic stress, temperature, toxins, UV radiation, and physical activity. Stress proteins increase the options available to avian ecologists for understanding how avian species respond to changes in the environment. PMID:17906822

Structural properties of liposomes from digital holographic microscopy

NASA Astrophysics Data System (ADS)

Di Maio, Isabelle L.; Carl, Daniel; Langehanenberg, Patrik; Valenzuela, Stella M.; Battle, Andrew R.; Al Khazaaly, Sabah; Killingsworth, Murray; Kemper, Bjorn; von Bally, Gert; Martin, Donald K.

2006-01-01

We have constructed liposomes from L alpha Phosphatidylcholine (PC) lipids, which are biomimetic lipids similar to those present in the membranes of mammalian cells. We propose an advance in the use of liposomes, such as for drug delivery, to incorporate into the liposomal membranes transport proteins that have been extracted from the lipid membranes of mammalian cells. In this paper, we describe the usage of a novel optical microscope to characterize the nanomechanical properties of these liposomes. We have applied the technique of digital holographic microscopy, using an instrument recently developed at the University of Münster, Germany. This system enabled us to measure quantitatively the structural changes in liposomes. We have investigated the deformations of these biomimetic lipids comprising these liposomes by applying osmotic stresses, in order to gain insight into the membrane environment prior to incorporation of cloned membrane transport proteins. This control of the nanomechanical properties is important in the stresses transmitted to mechanosensitive ion channels that we have incorporated into the liposomal membranes. These liposomes provide transporting vesicles that respond to mechanical stresses, such as those that occur during implantation.

Novel insights into RNP granules by employing the trypanosome's microtubule skeleton as a molecular sieve.

PubMed

Fritz, Melanie; Vanselow, Jens; Sauer, Nadja; Lamer, Stephanie; Goos, Carina; Siegel, T Nicolai; Subota, Ines; Schlosser, Andreas; Carrington, Mark; Kramer, Susanne

2015-09-18

RNP granules are ribonucleoprotein assemblies that regulate the post-transcriptional fate of mRNAs in all eukaryotes. Their exact function remains poorly understood, one reason for this is that RNP granule purification has not yet been achieved. We have exploited a unique feature of trypanosomes to prepare a cellular fraction highly enriched in starvation stress granules. First, granules remain trapped within the cage-like, subpellicular microtubule array of the trypanosome cytoskeleton while soluble proteins are washed away. Second, the microtubules are depolymerized and the granules are released. RNA sequencing combined with single molecule mRNA FISH identified the short and highly abundant mRNAs encoding ribosomal mRNAs as being excluded from granules. By mass spectrometry we have identified 463 stress granule candidate proteins. For 17/49 proteins tested by eYFP tagging we have confirmed the localization to granules, including one phosphatase, one methyltransferase and two proteins with a function in trypanosome life-cycle regulation. The novel method presented here enables the unbiased identification of novel RNP granule components, paving the way towards an understanding of RNP granule function. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Characterization of proteins in soybean roots under flooding and drought stresses.

PubMed

Oh, MyeongWon; Komatsu, Setsuko

2015-01-30

Flooding and drought affect soybean growth because soybean is a stress-sensitive crop. In 2-day-old plants exposed to 2-day flooding or drought, the fresh weight of roots was markedly suppressed, although the root morphology clearly differed between two conditions. To understand the response mechanisms of soybean to flooding and drought stresses, a gel-free proteomic technique was used. A total of 97 and 48 proteins were significantly changed in response to flooding and drought stresses, respectively. Proteins involved in protein synthesis were decreased by flooding stress and increased by drought. Glycolysis-related proteins were increased in roots by both flooding and drought stresses. Fermentation, stress, and cell wall-related proteins were increased in response to flooding stress, whereas cell organization and redox-related proteins were increased under drought stress. Among the identified proteins, three S-adenosylmethionine synthetases were commonly decreased and increased in response to flooding and drought stresses, respectively. The mRNA expression levels of S-adenosylmethionine synthetase genes displayed a similar tendency to the changes in protein abundance. These results suggest that S-adenosylmethionine synthetase is involved in the regulation of stress response because it was changed in response to flooding and drought stresses. This study reported on the response mechanisms of soybean to flooding and drought stresses using the gel-free proteomic technique. Proteins involved in protein synthesis were decreased by flooding stress and increased by drought. Glycolysis-related proteins were increased in roots by both flooding and drought stresses. Fermentation, stress, and cell wall-related proteins were increased in response to flooding stress, whereas cell organization and redox-related proteins were increased under drought stress. Among the identified proteins, three S-adenosylmethionine synthetases were commonly decreased and increased in response to flooding and drought stresses, respectively. The mRNA expression levels of S-adenosylmethionine synthetase genes displayed a similar tendency to the changes in protein abundance. These results suggest that S-adenosylmethionine synthetase is involved in the regulation of stress response because it was changed in response to flooding and drought stresses. Copyright © 2014 Elsevier B.V. All rights reserved.

Plant Abiotic Stress Proteomics: The Major Factors Determining Alterations in Cellular Proteome

PubMed Central

Kosová, Klára; Vítámvás, Pavel; Urban, Milan O.; Prášil, Ilja T.; Renaut, Jenny

2018-01-01

HIGHLIGHTS: Major environmental and genetic factors determining stress-related protein abundance are discussed.Major aspects of protein biological function including protein isoforms and PTMs, cellular localization and protein interactions are discussed.Functional diversity of protein isoforms and PTMs is discussed. Abiotic stresses reveal profound impacts on plant proteomes including alterations in protein relative abundance, cellular localization, post-transcriptional and post-translational modifications (PTMs), protein interactions with other protein partners, and, finally, protein biological functions. The main aim of the present review is to discuss the major factors determining stress-related protein accumulation and their final biological functions. A dynamics of stress response including stress acclimation to altered ambient conditions and recovery after the stress treatment is discussed. The results of proteomic studies aimed at a comparison of stress response in plant genotypes differing in stress adaptability reveal constitutively enhanced levels of several stress-related proteins (protective proteins, chaperones, ROS scavenging- and detoxification-related enzymes) in the tolerant genotypes with respect to the susceptible ones. Tolerant genotypes can efficiently adjust energy metabolism to enhanced needs during stress acclimation. Stress tolerance vs. stress susceptibility are relative terms which can reflect different stress-coping strategies depending on the given stress treatment. The role of differential protein isoforms and PTMs with respect to their biological functions in different physiological constraints (cellular compartments and interacting partners) is discussed. The importance of protein functional studies following high-throughput proteome analyses is presented in a broader context of plant biology. In summary, the manuscript tries to provide an overview of the major factors which have to be considered when interpreting data from proteomic studies on stress-treated plants. PMID:29472941

Heat stress and cardiovascular, hormonal, and heat shock proteins in humans.

PubMed

Iguchi, Masaki; Littmann, Andrew E; Chang, Shuo-Hsiu; Wester, Lydia A; Knipper, Jane S; Shields, Richard K

2012-01-01

Conditions such as osteoarthritis, obesity, and spinal cord injury limit the ability of patients to exercise, preventing them from experiencing many well-documented physiologic stressors. Recent evidence indicates that some of these stressors might derive from exercise-induced body temperature increases. To determine whether whole-body heat stress without exercise triggers cardiovascular, hormonal, and extracellular protein responses of exercise. Randomized controlled trial. University research laboratory. Twenty-five young, healthy adults (13 men, 12 women; age = 22.1 ± 2.4 years, height = 175.2 ± 11.6 cm, mass = 69.4 ± 14.8 kg, body mass index = 22.6 ± 4.0) volunteered. Participants sat in a heat stress chamber with heat (73°C) and without heat (26°C) stress for 30 minutes on separate days. We obtained blood samples from a subset of 13 participants (7 men, 6 women) before and after exposure to heat stress. Extracellular heat shock protein (HSP72) and catecholamine plasma concentration, heart rate, blood pressure, and heat perception. After 30 minutes of heat stress, body temperature measured via rectal sensor increased by 0.8°C. Heart rate increased linearly to 131.4 ± 22.4 beats per minute (F₆,₂₄ = 186, P < .001) and systolic and diastolic blood pressure decreased by 16 mm Hg (F₆,₂₄ = 10.1, P < .001) and 5 mm Hg (F₆,₂₄ = 5.4, P < .001), respectively. Norepinephrine (F₁,₁₂ = 12.1, P = .004) and prolactin (F₁,₁₂ = 30.2, P < .001) increased in the plasma (58% and 285%, respectively) (P < .05). The HSP72 (F₁,₁₂ = 44.7, P < .001) level increased with heat stress by 48.7% ± 53.9%. No cardiovascular or blood variables showed changes during the control trials (quiet sitting in the heat chamber with no heat stress), resulting in differences between heat and control trials. We found that whole-body heat stress triggers some of the physiologic responses observed with exercise. Future studies are necessary to investigate whether carefully prescribed heat stress constitutes a method to augment or supplement exercise.

Endoplasmic Reticulum Stress and Oxidative Stress: A Vicious Nexus Implicated in Bowel Disease Pathophysiology

PubMed Central

Chong, Wai Chin; Shastri, Madhur D.; Eri, Rajaraman

2017-01-01

The endoplasmic reticulum (ER) is a complex protein folding and trafficking organelle. Alteration and discrepancy in the endoplasmic reticulum environment can affect the protein folding process and hence, can result in the production of misfolded proteins. The accumulation of misfolded proteins causes cellular damage and elicits endoplasmic reticulum stress. Under such stress conditions, cells exhibit reduced functional synthesis, and will undergo apoptosis if the stress is prolonged. To resolve the ER stress, cells trigger an intrinsic mechanism called an unfolded protein response (UPR). UPR is an adaptive signaling process that triggers multiple pathways through the endoplasmic reticulum transmembrane transducers, to reduce and remove misfolded proteins and improve the protein folding mechanism, in order to improve and maintain endoplasmic reticulum homeostasis. An increasing number of studies support the view that oxidative stress has a strong connection with ER stress. During the protein folding process, reactive oxygen species are produced as by-products, leading to impaired reduction-oxidation (redox) balance conferring oxidative stress. As the protein folding process is dependent on redox homeostasis, the oxidative stress can disrupt the protein folding mechanism and enhance the production of misfolded proteins, causing further ER stress. It is proposed that endoplasmic reticulum stress and oxidative stress together play significant roles in the pathophysiology of bowel diseases. PMID:28379196

Endoplasmic Reticulum Stress and Oxidative Stress: A Vicious Nexus Implicated in Bowel Disease Pathophysiology.

PubMed

Chong, Wai Chin; Shastri, Madhur D; Eri, Rajaraman

2017-04-05

The endoplasmic reticulum (ER) is a complex protein folding and trafficking organelle. Alteration and discrepancy in the endoplasmic reticulum environment can affect the protein folding process and hence, can result in the production of misfolded proteins. The accumulation of misfolded proteins causes cellular damage and elicits endoplasmic reticulum stress. Under such stress conditions, cells exhibit reduced functional synthesis, and will undergo apoptosis if the stress is prolonged. To resolve the ER stress, cells trigger an intrinsic mechanism called an unfolded protein response (UPR). UPR is an adaptive signaling process that triggers multiple pathways through the endoplasmic reticulum transmembrane transducers, to reduce and remove misfolded proteins and improve the protein folding mechanism, in order to improve and maintain endoplasmic reticulum homeostasis. An increasing number of studies support the view that oxidative stress has a strong connection with ER stress. During the protein folding process, reactive oxygen species are produced as by-products, leading to impaired reduction-oxidation (redox) balance conferring oxidative stress. As the protein folding process is dependent on redox homeostasis, the oxidative stress can disrupt the protein folding mechanism and enhance the production of misfolded proteins, causing further ER stress. It is proposed that endoplasmic reticulum stress and oxidative stress together play significant roles in the pathophysiology of bowel diseases.

Tudor-SN, a component of stress granules, regulates growth under salt stress by modulating GA20ox3 mRNA levels in Arabidopsis

PubMed Central

Yan, Chunxia; Yan, Zongyun; Wang, Yizheng; Yan, Xiaoyuan; Han, Yuzhen

2014-01-01

The Tudor-SN protein (TSN) is universally expressed and highly conserved in eukaryotes. In Arabidopsis, TSN is reportedly involved in stress adaptation, but the mechanism involved in this adaptation is not understood. Here, we provide evidence that TSN regulates the mRNA levels of GA20ox3, a key enzyme for gibberellin (GA) biosynthesis. The levels of GA20ox3 transcripts decreased in TSN1/TSN2 RNA interference (RNAi) transgenic lines and increased in TSN1 over-expression (OE) transgenic lines. The TSN1 OE lines displayed phenotypes that may be attributed to the overproduction of GA. No obvious defects were observed in the RNAi transgenic lines under normal conditions, but under salt stress conditions these lines displayed slower growth than wild-type (WT) plants. Two mutants of GA20ox3, ga20ox3-1 and -2, also showed slower growth under stress than WT plants. Moreover, a higher accumulation of GA20ox3 transcripts was observed under salt stress. The results of a western blot analysis indicated that higher levels of TSN1 accumulated after salt treatment than under normal conditions. Subcellular localization studies showed that TSN1 was uniformly distributed in the cytoplasm under normal conditions but accumulated in small granules and co-localized with RBP47, a marker protein for stress granules (SGs), in response to salt stress. The results of RNA immunoprecipitation experiments indicated that TSN1 bound GA20ox3 mRNA in vivo. On the basis of these findings, we conclude that TSN is a novel component of plant SGs that regulates growth under salt stress by modulating levels of GA20ox3 mRNA. PMID:25205572

Tissue-specific accumulation and regulation of zeaxanthin epoxidase in Arabidopsis reflect the multiple functions of the enzyme in plastids.

PubMed

Schwarz, Nadine; Armbruster, Ute; Iven, Tim; Brückle, Lena; Melzer, Michael; Feussner, Ivo; Jahns, Peter

2015-02-01

The enzyme zeaxanthin epoxidase (ZEP) catalyzes the conversion of zeaxanthin to violaxanthin, a key reaction for ABA biosynthesis and the xanthophyll cycle. Both processes are important for acclimation to environmental stress conditions, in particular drought (ABA biosynthesis) and light (xanthophyll cycle) stress. Hence, both ZEP functions may require differential regulation to optimize plant fitness. The key to understanding the function of ZEP in both stress responses might lie in its spatial and temporal distribution in plant tissues. Therefore, we analyzed the distribution of ZEP in plant tissues and plastids under drought and light stress by use of a ZEP-specific antibody. In addition, we determined the pigment composition of the plant tissues and chloroplast membrane subcompartments in response to these stresses. The ZEP protein was detected in all plant tissues (except flowers) concomitant with xanthophylls. The highest levels of ZEP were present in leaf chloroplasts and root plastids. Within chloroplasts, ZEP was localized predominantly in the thylakoid membrane and stroma, while only a small fraction was bound by the envelope membrane. Light stress affected neither the accumulation nor the relative distribution of ZEP in chloroplasts, while drought stress led to an increase of ZEP in roots and to a degradation of ZEP in leaves. However, drought stress-induced increases in ABA were similar in both tissues. These data support a tissue- and stress-specific accumulation of the ZEP protein in accordance with its different functions in ABA biosynthesis and the xanthophyll cycle. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

An A20/AN1-type zinc finger protein modulates gibberellins and abscisic acid contents and increases sensitivity to abiotic stress in rice (Oryza sativa).

PubMed

Zhang, Ye; Lan, Hongxia; Shao, Qiaolin; Wang, Ruqin; Chen, Hui; Tang, Haijuan; Zhang, Hongsheng; Huang, Ji

2016-01-01

The plant hormones gibberellins (GA) and abscisic acid (ABA) play important roles in plant development and stress responses. Here we report a novel A20/AN1-type zinc finger protein ZFP185 involved in GA and ABA signaling in the regulation of growth and stress response. ZFP185 was constitutively expressed in various rice tissues. Overexpression of ZFP185 in rice results in a semi-dwarfism phenotype, reduced cell size, and the decrease of endogenous GA3 content. By contrast, higher GA3 content was observed in RNAi plants. The application of exogenous GA3 can fully rescue the semi-dwarfism phenotype of ZFP185 overexpressing plants, suggesting the negative role of ZFP185 in GA biosynthesis. Besides GA, overexpression of ZFP185 decreased ABA content and expression of several ABA biosynthesis-related genes. Moreover, it was found that ZFP185, unlike previously known A20/AN1-type zinc finger genes, increases sensitivity to drought, cold, and salt stresses, implying the negative role of ZFP185 in stress tolerance. ZFP185 was localized in the cytoplasm and lacked transcriptional activation potential. Our study suggests that ZFP185 regulates plant growth and stress responses by affecting GA and ABA biosynthesis in rice. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Influence of Quercetin in the Temporal Regulation of Redox Homeostasis in Drosophila melanogaster.

PubMed

Subramanian, Perumal; Kaliyamoorthy, Kanimozhi; Jayapalan, Jaime Jacqueline; Abdul-Rahman, Puteri Shafinaz; Haji Hashim, Onn

2017-01-01

Numerous biological processes are governed by the biological clock. Studies using Drosophila melanogaster (L.) are valuable that could be of importance for their effective applications on rodent studies. In this study, the beneficial role of quercetin (a flavonoid) on H2O2 induced stress in D. melanogaster was investigated. D. melanogaster flies were divided into four groups (group I - control, group II - H2O2 (acute exposure), group III - quercetin, and group IV - quercetin + H2O2 treated). Negative geotaxis assay, oxidative stress indicators (protein carbonyls, thiobarbituric reactive substances [TBARS]), and antioxidants (superoxide dismutase [SOD], catalase [CAT], glutathione-S-transferase [GST], glutathione peroxidase, and reduced glutathione [GSH]) were measured at 4 h intervals over 24 h and temporal expression of heat shock protein-70 (Hsp70), Upd1 (homolog of IL-6 in Drosophila), and nitric oxide synthase (Nos) was analyzed by Western blotting. Groups II and IV showed altered biochemical rhythms (compared with controls). Decreased mesor values of negative geotaxis, SOD, CAT, GST, and GSH were noticed in H2O2, increased mesor of oxidative stress indicators (TBARS and protein carbonyl content) and a reversibility of the rhythmic characteristics were conspicuous after quercetin treatment. The expression levels of Hsp70, Upd1, and Nos were noticeably maximum at 04:00. Significant elevation of expression by H2O2 was nearly normalized by quercetin treatment. The possible mechanism by which quercetin modulates oxidant-antioxidant imbalance under oxidative stress could be ascribed to the modulation of the rhythmic properties. Our results will be helpful to understand the molecular interlink between circadian rhythm and oxidative stress mechanism. © The Author 2017. Published by Oxford University Press on behalf of the Entomological Society of America.

Assessment of thermal stress adaptation by monitoring Hsp70 and MnSOD in the freshwater gastropod, Bellamya bengalensis (Lamark 1882).

PubMed

Dutta, Sangita Maiti; Mustafi, Soumyajit Banerjee; Raha, Sanghamitra; Chakraborty, Susanta Kumar

2014-12-01

Expression of the stress biomarkers 70-kDa heat shock proteins (Hsp70) and manganese superoxide dismutase (MnSOD) was measured as the molecular basis of adaptive response against increased experimental temperatures (32-40 °C for a span of 24-72 h) on the fresh water molluscan species, Bellamya bengalensis (Lamark 1882). The experimental snail specimens were collected during summer and winter seasons from two contrasting wetlands: an ecorestored (free from human interference) site (SI) and other experiencing anthropogenic stresses (SII). The mortality rate of the B. bengalensis and the immunoblotting of MnSOD and Hsp70 of their digestive glands were performed at regular intervals during the period of heat stress. The SI provided a lower stress environment based on physicochemical parameters such as pH, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), and alkalinity for the survival of test species, although both sites experienced mortality due to thermal stresses. The parity in protein expressions displayed a uniform mode of adaptive impact to temperature elevations in both field and laboratory exposure. The Hsp70 expression was minimal at lower thermal stress, but increased with a rise in temperature. It is very likely that higher Hsp70 levels are not directly related to survival or adaptation. In contrast, MnSOD levels appeared to be an indicator of adaptive responses vis-a-vis survival of the animals. So, the expression levels of a universal free radical scavenger like MnSOD are recognized as a potential biomarker in a bioindicator species like Bellamya.

Sequence-Based Analysis of Thermal Adaptation and Protein Energy Landscapes in an Invasive Blue Mussel (Mytilus galloprovincialis).

PubMed

Saarman, Norah P; Kober, Kord M; Simison, W Brian; Pogson, Grant H

2017-10-01

Adaptive responses to thermal stress in poikilotherms plays an important role in determining competitive ability and species distributions. Amino acid substitutions that affect protein stability and modify the thermal optima of orthologous proteins may be particularly important in this context. Here, we examine a set of 2,770 protein-coding genes to determine if proteins in a highly invasive heat tolerant blue mussel (Mytilus galloprovincialis) contain signals of adaptive increases in protein stability relative to orthologs in a more cold tolerant M. trossulus. Such thermal adaptations might help to explain, mechanistically, the success with which the invasive marine mussel M. galloprovincialis has displaced native species in contact zones in the eastern (California) and western (Japan) Pacific. We tested for stabilizing amino acid substitutions in warm tolerant M. galloprovincialis relative to cold tolerant M. trossulus with a generalized linear model that compares in silico estimates of recent changes in protein stability among closely related congeners. Fixed substitutions in M. galloprovincialis were 3,180.0 calories per mol per substitution more stabilizing at genes with both elevated dN/dS ratios and transcriptional responses to heat stress, and 705.8 calories per mol per substitution more stabilizing across all 2,770 loci investigated. Amino acid substitutions concentrated in a small number of genes were more stabilizing in M. galloprovincialis compared with cold tolerant M. trossulus. We also tested for, but did not find, enrichment of a priori GO terms in genes with elevated dN/dS ratios in M. galloprovincialis. This might indicate that selection for thermodynamic stability is generic across all lineages, and suggests that the high change in estimated protein stability that we observed in M. galloprovincialis is driven by selection for extra stabilizing substitutions, rather than by higher incidence of selection in a greater number of genes in this lineage. Nonetheless, our finding of more stabilizing amino acid changes in the warm adapted lineage is important because it suggests that adaption for thermal stability has contributed to M. galloprovincialis' superior tolerance to heat stress, and that pairing tests for positive selection and tests for transcriptional response to heat stress can identify candidates of protein stability adaptation. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Modulation of proteostasis counteracts oxidative stress and affects DNA base excision repair capacity in ATM-deficient cells.

PubMed

Poletto, Mattia; Yang, Di; Fletcher, Sally C; Vendrell, Iolanda; Fischer, Roman; Legrand, Arnaud J; Dianov, Grigory L

2017-09-29

Ataxia telangiectasia (A-T) is a syndrome associated with loss of ATM protein function. Neurodegeneration and cancer predisposition, both hallmarks of A-T, are likely to emerge as a consequence of the persistent oxidative stress and DNA damage observed in this disease. Surprisingly however, despite these severe features, a lack of functional ATM is still compatible with early life, suggesting that adaptation mechanisms contributing to cell survival must be in place. Here we address this gap in our knowledge by analysing the process of human fibroblast adaptation to the lack of ATM. We identify profound rearrangement in cellular proteostasis occurring very early on after loss of ATM in order to counter protein damage originating from oxidative stress. Change in proteostasis, however, is not without repercussions. Modulating protein turnover in ATM-depleted cells also has an adverse effect on the DNA base excision repair pathway, the major DNA repair system that deals with oxidative DNA damage. As a consequence, the burden of unrepaired endogenous DNA lesions intensifies, progressively leading to genomic instability. Our study provides a glimpse at the cellular consequences of loss of ATM and highlights a previously overlooked role for proteostasis in maintaining cell survival in the absence of ATM function. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

RING Type E3 Ligase CaAIR1 in Pepper Acts in the Regulation of ABA Signaling and Drought Stress Response.

PubMed

Park, Chanmi; Lim, Chae Woo; Baek, Woonhee; Lee, Sung Chul

2015-09-01

Several E3 ubiquitin ligases have been associated with the response to abiotic and biotic stresses in higher plants. Here, we report that the hot pepper (Capsicum annuum) ABA-Insensitive RING protein 1 gene (CaAIR1) is essential for a hypersensitive response to drought stress. CaAIR1 contains a C3HC4-type RING finger motif, which plays a role for attachment of ubiquitins to the target protein, and a putative transmembrane domain. The expression levels of CaAIR1 are up-regulated in pepper leaves by ABA treatments, drought and NaCl, suggesting its role in the response to abiotic stress. Our analysis showed that CaAIR1 displays self-ubiquitination and is localized in the nucleus. We generated CaAIR1-silenced peppers via virus-induced gene silencing (VIGS) and CaAIR1-overexpressing (OX) transgenic Arabidopsis plants to evaluate their responses to ABA and drought. VIGS of CaAIR1 in pepper plants conferred an enhanced tolerance to drought stress, which was accompanied by low levels of transpirational water loss in the drought-treated leaves. CaAIR1-OX plants displayed an impaired sensitivity to ABA during seed germination, seedling and adult stages. Moreover, these plants showed enhanced sensitivity to drought stress because of reduced stomatal closure and decreased expression of stress-responsive genes. Thus, our data indicate that CaAIR1 is a negative regulator of the ABA-mediated drought stress tolerance mechanism. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Effects of heat and other inducers of the stress response on protein degradation in Chinese hamster and Drosophila cells.

PubMed

Westwood, J T; Steinhardt, R A

1989-04-01

Many recent studies have suggested that heat and other inducers of the heat shock (stress) response in eukaryotic cells might result in the generation of abnormal proteins which would result in the overloading of protein degradation systems and the stabilization of proteins involved in positively regulating heat shock (hs) gene expression. In this study we have examined the effects different heat treatments and other hs inducers have on protein degradation in Chinese hamster ovary (CHO) and Drosophila Kc and Schneider cells. We have found that intermediate temperatures which induced the hs response (42 degrees C in CHO and 34 degrees C in Kc cells) did increase protein degradation rates whereas, higher temperatures which also induced the hs response (45 degrees C in CHO and 37 degrees C in Kc cells) initially increased but then decreased protein degradation rates. While these results are consistent with a model in which the protein degradation system is being overloaded and/or components of it are being depleted, we have found several conditions which induce hs proteins which rule out this mechanism. Exposure of either cell type to amino acid analogs (5 mM canavanine or 5 mM S-aminoethyl cysteine) resulted in the rapid degradation of those proteins which had incorporated the analogs in both CHO and Drosophila cells. However, the addition of analogs had little or no effect on the degradation of preexisting proteins, indicating that the introduction of abnormal proteins probably didn't overload the protein degradation system(s). The addition of 100 microM cadmium sulfate or 100 microM sodium arsenite had little or no effect on protein degradation rates in CHO cells even though both were good inducers of the hs proteins. Thus, exposure to inducers of the hs response does not universally increase protein degradation rates nor does it stabilize preexisting proteins. Therefore, the degradation of abnormal proteins is probably not involved in inducing the hs genes.

What to Do about Being Overwhelmed: Graduate Students, Stress and University Services

ERIC Educational Resources Information Center

Oswalt, Sara B.; Riddock, Christina C.

2007-01-01

Few studies have examined graduate students and stress. At a large, Southeastern university, 223 graduate students completed a survey about factors contributing their stress, current coping strategies and related university services. A majority felt stressed (48.9%) or very stressed (24.7%). There were significant differences in coping strategies…

Model for Stress-induced Protein Degradation in Lemna minor1

PubMed Central

Cooke, Robert J.; Roberts, Keith; Davies, David D.

1980-01-01

Transfer of Lemna minor fronds to adverse or stress conditions produces a large increase in the rate of protein degradation. Cycloheximide partially inhibits stress-induced protein degradation and also partially inhibits the protein degradation which occurs in the absence of stress. The increased protein degradation does not appear to be due to an increase in activity of soluble proteolytic enzymes. Biochemical evidence indicates that stress, perhaps acting via hormones, affects the permeability of certain membranes, particularly the tonoplast. A general model for stress-induced protein degradation is presented in which changes in membrane properties allow vacuolar proteolytic enzymes increased access to cytoplasmic proteins. PMID:16661588

Isolation and identification of peanut leaf proteins regulated by water stress.

PubMed

Akkasaeng, Chutipong; Tantisuwichwong, Napaporn; Chairam, Issariya; Prakrongrak, Narumon; Jogloy, Sanun; Pathanothai, Aran

2007-05-15

Water deficits trigger signaling cascades leading to modulation of protein expression in plant tissues. Identification of peanut leaf proteins regulated by water stress provides some insights of cellular and molecular response of peanut plants to drought stress. Peanut variety Khon Kaen 4, a water-stress sensitive variety, was grown in a growth chamber under controlled environment. Water stress was imposed on day 30 after seedling emergence by withholding watering peanut plants for 6 days as compared to plants adequately supplied with water. Total protein were prepared from a leaflet of fully expanded leaf on the main stem. Proteins were separated in duplicated gels using two-dimensional gel electrophoresis and visualized by silver nitrate staining. Image analysis was performed using ImageMaster 2D Platinum 5.0 to determine proteins regulated by water stress. Molecular mass and isoelectric point of each regulated protein were used in database queries for protein identification. One protein was induced under water stress and the homologous protein was identified as Serine/threonine-protein phosphatase PP 1. Five proteins were down-regulated by water deficit. The homologous proteins were chaperone protein DNAJ, auxin-responsive protein IAA29, peroxidase 43, caffeoyl-CoA O-methyltransferase and SNF1-related protein kinase regulatory subunit beta-2. Down-regulated proteins may be associated with sensitivity of the peanut variety to water stress.

Proteomic analysis of endoplasmic reticulum stress responses in rice seeds.

PubMed

Qian, Dandan; Tian, Lihong; Qu, Leqing

2015-09-23

The defects in storage proteins secretion in the endosperm of transgenic rice seeds often leads to endoplasmic reticulum (ER) stress, which produces floury and shrunken seeds, but the mechanism of this response remains unclear. We used an iTRAQ-based proteomics analysis of ER-stressed rice seeds due to the endosperm-specific suppression of OsSar1 to identify changes in the protein levels in response to ER stress. ER stress changed the expression of 405 proteins in rice seed by >2.0- fold compared with the wild-type control. Of these proteins, 140 were upregulated and 265 were downregulated. The upregulated proteins were mainly involved in protein modification, transport and degradation, and the downregulated proteins were mainly involved in metabolism and stress/defense responses. A KOBAS analysis revealed that protein-processing in the ER and degradation-related proteasome were the predominant upregulated pathways in the rice endosperm in response to ER stress. Trans-Golgi protein transport was also involved in the ER stress response. Combined with bioinformatic and molecular biology analyses, our proteomic data will facilitate our understanding of the systemic responses to ER stress in rice seeds.

Stress and Protein Turnover in Lemna minor1

PubMed Central

Cooke, Robert J.; Oliver, Jane; Davies, David D.

1979-01-01

Transfer of fronds of Lemna minor L. to adverse growth conditions or stress situations causes a lowering of the growth rate and a loss of soluble protein per frond, the extent of the loss being dependent on the nature of the stress. The loss or protein is due to two factors: (a) a decrease in the rate constant of protein synthesis (ks); (b) an increase in the rate constant of protein degradation (kd). In plants adapted to the stresses, protein synthesis increases and the initially rapid rate of proteolysis is reduced. Addition of abscisic acid both lowers ks and increases kd, whereas benzyladenine seems to alleviate the effects of stress on protein content by decreasing kd rather than by altering ks. Based on the measurement of enzyme activities, stress-induced protein degradation appears to be a general phenomenon, affecting many soluble proteins. The adaptive significance of stress-induced proteolysis is discussed. PMID:16661102

Proteomic analysis of spring freeze-stress responsive proteins in leaves of bread wheat (Triticum aestivum L.).

PubMed

Han, Qiaoxia; Kang, Guozhang; Guo, Tiancai

2013-02-01

Following three-day exposure to -5 °C simulated spring freeze stress, wheat plants at the anther connective tissue formation phase of spike development displayed the drooping and wilting of leaves and markedly increased rates of relative electrolyte leakage. We analysed freeze-stress responsive proteins in wheat leaves at one and three days following freeze-stress exposure, using two-dimensional electrophoresis and matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Our results indicate that out of 75 protein spots successfully identified under freeze-stress conditions 52 spots were upregulated and 18 were downregulated. These spring freeze-stress responsive proteins were involved in signal transduction, stress/defence/detoxification, protein metabolism (i.e. translation, processing, and degradation), photosynthesis, amino acid metabolism, carbohydrate metabolism, and energy pathways, and may therefore be functionally relevant for many biological processes. The enhanced accumulation of signal transduction proteins such as a C2H2 zinc finger protein, stress/defence/detoxification proteins including LEA-related COR protein, disease resistance protein, Cu/Zn superoxide dismutase, and two ascorbate peroxidases may play crucial roles in the mechanisms of response to spring freeze stress in wheat plants. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Proteomic changes in female rat hippocampus following exposure to a terrified sound stress.

PubMed

Yang, Juan; Hu, Lili; Song, Tusheng; Liu, Yong; Wu, Qiuhua; Zhao, Lingyu; Liu, Liying; Zhao, Xiaoge; Zhang, Dianzeng; Huang, Chen

2014-06-01

Stress plays a profound role in the onset of affective disorders, including an elevation in risk factors for depression and anxiety. Women are twice as vulnerable to stress as men because of greater sensitivity to a substance produced during times of anxiety. To better define the abnormal proteins implicated in cognitive deficits and other stress-induced dysfunction, female rats were exposed to terrified sound stress, and two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) were utilized to determine the differential protein expression in the hippocampus in sound-stressed female rats compared with controls. Quantitative differences were found in 44 protein spots which were differentially expressed between the stressed and control groups (fold change of >2; p < 0.01). Eighteen protein spots were downregulated, and 26 protein spots were upregulated in the stressed group. The seven most differentially expressed proteins were identified and validated as follows: dihydropyrimidinase-related protein 2 (DRP-2), creatine kinase B type, dynamin-1 protein, alpha-internexin, glial fibrillary acidic protein beta, gamma-enolase, and peptidyl-prolyl cis-trans isomerase A. Changes in protein levels were detected in the hippocampus of female rats subjected to terrified sound stress. The findings herein may open new opportunities for further investigations on the modulation induced in the hippocampus by stress at the molecular level, especially with respect to females stress.

[Effect of endoplasmic reticulum stress in trophocytes on the pathogenesis of intrahepatic cholestasis of pregnancy].

PubMed

Yu, Y; Zhou, C L; Yu, T T; Han, X J; Shi, H Y; Wang, H Z; Shen, J J; He, J

2017-06-25

Objective: To evaluate the effect of endoplasmic reticulum stress in trophocytes, in patients with intrahepatic cholestasis of pregnancy (ICP). Methods: Sixty-one pregnant women who were hospitalized in Women's Hospital, School of Medicine, Zhejiang University from January to December 2015 were recruited. Thirty-one women who were diagnosed as ICP were defined as the ICP group and 30 healthy pregnant women were defined as the control group. The localization and expression intensity of glucose regulated protein 78 (GRP-78) in placental tissues were detected by immunohistochemistry technique. Electronic microscope was used to observe ultra-microstructure change of the endoplasmic reticulum in trophocytes and cell line Swan71. Reverse transcription (RT)-PCR and western blot were used to investigate the expression of GRP-78 mRNA and protein in Swan 71 cell. Results: (1) GRP-78 protein was mainly expressed in the cytoplasm of cytotrophoblasts and syncytiotrophoblasts. The protein expression of GRP-78 in placentas of the ICP group (13.2±2.4) was significantly higher than that in the control group (7.8±1.3, P< 0.01). (2) The volume of endoplasmie reticulum did not increase and the microvilli developed well, with no swelling and no expansion of endoplasmic reticulum in the control group.In the ICP group, microvilli injury, endoplasmic reticulum edema were found; the volume of endoplasmic reticulum increased, with dilation, vacuolation and significant degranulation. After treated with 100 μmol/L cholyglycine for 24 hours, universal dilatation of the endoplasmic reticulum were seen in the Swan71 cells. (3) In Swan71 cells, cholylglycine displayed a concentration-dependent up-regulation on the expression of GRP-78. The expressions of GRP-78 mRNA in 0, 25, 50, 100 μmol/L cholylglycine experimental group were 1.01±0.17, 2.17±0.16, 5.47±0.36, 5.65±0.82, respectively. The expression of GRP-78 protein in 0, 25, 50, 100 μmol/L cholylglycine experimental group were 1.01±0.04, 1.17±0.15, 1.33±0.13, 1.73±0.13, respectively. The expression of GRP-78 mRNA and protein in 100 and 50 μmol/L cholylglycine experimental group were significantly higher than 0 μmol/L (all P< 0.01). Conclusion: The obvious expansion of endoplasmic reticulum and the increased expression of GRP-78 in trophocytes indicated that endoplasmic reticulum stress of trophocytes may be involved in the pathogenesis of ICP.

Gel-Free/Label-Free Proteomic Analysis of Endoplasmic Reticulum Proteins in Soybean Root Tips under Flooding and Drought Stresses.

PubMed

Wang, Xin; Komatsu, Setsuko

2016-07-01

Soybean is a widely cultivated crop; however, it is sensitive to flooding and drought stresses. The adverse environmental cues cause the endoplasmic reticulum (ER) stress due to accumulation of unfolded or misfolded proteins. To investigate the mechanisms in response to flooding and drought stresses, ER proteomics was performed in soybean root tips. The enzyme activity of NADH cytochrome c reductase was two-fold higher in the ER than other fractions, indicating that the ER was isolated with high purity. Protein abundance of ribosomal proteins was decreased under both stresses compared to control condition; however, the percentage of increased ribosomes was two-fold higher in flooding compared to drought. The ER proteins related to protein glycosylation and signaling were in response to both stresses. Compared to control condition, calnexin was decreased under both stresses; however, protein disulfide isomerase-like proteins and heat shock proteins were markedly decreased under flooding and drought conditions, respectively. Furthermore, fewer glycoproteins and higher levels of cytosolic calcium were identified under both stresses compared to control condition. These results suggest that reduced accumulation of glycoproteins in response to both stresses might be due to dysfunction of protein folding through calnexin/calreticulin cycle. Additionally, the increased cytosolic calcium levels induced by flooding and drought stresses might disturb the ER environment for proper protein folding in soybean root tips.

Protein degradation and dynamic tRNA thiolation fine-tune translation at elevated temperatures.

PubMed

Tyagi, Kshitiz; Pedrioli, Patrick G A

2015-05-19

Maintenance of protein quality control has implications in various processes such as neurodegeneration and ageing. To investigate how environmental insults affect this process, we analysed the proteome of yeast continuously exposed to mild heat stress. In agreement with previous transcriptomics studies, amongst the most marked changes, we found up-regulation of cytoprotective factors; a shift from oxidative phosphorylation to fermentation; and down-regulation of translation. Importantly, we also identified a novel, post-translationally controlled, component of the heat shock response. The abundance of Ncs2p and Ncs6p, two members of the URM1 pathway responsible for the thiolation of wobble uridines in cytoplasmic tRNAs tK(UUU), tQ(UUG) and tE(UUC), is down-regulated in a proteasomal dependent fashion. Using random forests we show that this results in differential translation of transcripts with a biased content for the corresponding codons. We propose that the role of this pathway in promoting catabolic and inhibiting anabolic processes, affords cells with additional time and resources needed to attain proper protein folding under periods of stress. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Analysis of soybean root proteins affected by gibberellic acid treatment under flooding stress.

PubMed

Oh, Myeong Won; Nanjo, Yohei; Komatsu, Setsuko

2014-01-01

Flooding is a serious abiotic stress for soybean because it restricts growth and reduces grain yields. To investigate the effect of gibberellic acid (GA) on soybean under flooding stress, root proteins were analyzed using a gel-free proteomic technique. Proteins were extracted from the roots of 4-days-old soybean seedlings exposed to flooding stress in the presence and absence of exogenous GA3 for 2 days. A total of 307, 324, and 250 proteins were identified from untreated, and flooding-treated soybean seedlings without or with GA3, respectively. Secondary metabolism- and cell-related proteins, and proteins involved in protein degradation/synthesis were decreased by flooding stress; however, the levels of these proteins were restored by GA3 supplementation under flooding. Fermentation- and cell wall-related proteins were not affected by GA3 supplementation. Furthermore, putative GA-responsive proteins, which were identified by the presence of a GA-responsive element in the promoter region, were less abundant by flooding stress; however, these proteins were more abundant by GA3 supplementation under flooding. Taken together, these results suggest that GA3 affects the abundance of proteins involved in secondary metabolism, cell cycle, and protein degradation/synthesis in soybeans under flooding stress.

Technical and clinical aspects of cortisol as a biochemical marker of chronic stress.

PubMed

Lee, Do Yup; Kim, Eosu; Choi, Man Ho

2015-04-01

Stress is now recognized as a universal premorbid factor associated with many risk factors of various chronic diseases. Acute stress may induce an individual's adaptive response to environmental demands. However, chronic, excessive stress causes cumulative negative impacts on health outcomes through "allostatic load". Thus, monitoring the quantified levels of long-term stress mediators would provide a timely opportunity for prevention or earlier intervention of stress-related chronic illnesses. Although either acute or chronic stress could be quantified through measurement of changes in physiological parameters such as heart rate, blood pressure, and levels of various metabolic hormones, it is still elusive to interpret whether the changes in circulating levels of stress mediators such as cortisol can reflect the acute, chronic, or diurnal variations. Both serum and salivary cortisol levels reveal acute changes at a single point in time, but the overall long-term systemic cortisol exposure is difficult to evaluate due to circadian variations and its protein-binding capacity. Scalp hair has a fairy predictable growth rate of approximately 1 cm/month, and the most 1 cm segment approximates the last month's cortisol production as the mean value. The analysis of cortisol in hair is a highly promising technique for the retrospective assessment of chronic stress.

Redox Activation of the Universally Conserved ATPase YchF by Thioredoxin 1.

PubMed

Hannemann, Liya; Suppanz, Ida; Ba, Qiaorui; MacInnes, Katherine; Drepper, Friedel; Warscheid, Bettina; Koch, Hans-Georg

2016-01-20

YchF/Ola1 are unconventional members of the universally conserved GTPase family because they preferentially hydrolyze ATP rather than GTP. These ATPases have been associated with various cellular processes and pathologies, including DNA repair, tumorigenesis, and apoptosis. In particular, a possible role in regulating the oxidative stress response has been suggested for both bacterial and human YchF/Ola1. In this study, we analyzed how YchF responds to oxidative stress and how it potentially regulates the antioxidant response. Our data identify a redox-regulated monomer-dimer equilibrium of YchF as a key event in the functional cycle of YchF. Upon oxidative stress, the oxidation of a conserved and surface-exposed cysteine residue promotes YchF dimerization, which is accompanied by inhibition of the ATPase activity. No dimers were observed in a YchF mutant lacking this cysteine. In vitro, the YchF dimer is dissociated by thioredoxin 1 (TrxA) and this stimulates the ATPase activity. The physiological significance of the YchF-thioredoxin 1 interaction was demonstrated by in vivo cross-linking, which validated this interaction in living cells. This approach also revealed that both the ATPase domain and the helical domain of YchF are in contact with TrxA. YchF/Ola1 are the first redox-regulated members of the universally conserved GTPase family and are inactivated by oxidation of a conserved cysteine residue within the nucleotide-binding motif. Our data provide novel insights into the regulation of the so far ill-defined YchF/Ola1 family of proteins and stipulate their role as negative regulators of the oxidative stress response.

Redox Activation of the Universally Conserved ATPase YchF by Thioredoxin 1

PubMed Central

Hannemann, Liya; Suppanz, Ida; Ba, Qiaorui; MacInnes, Katherine; Drepper, Friedel; Warscheid, Bettina

2016-01-01

Abstract Aims: YchF/Ola1 are unconventional members of the universally conserved GTPase family because they preferentially hydrolyze ATP rather than GTP. These ATPases have been associated with various cellular processes and pathologies, including DNA repair, tumorigenesis, and apoptosis. In particular, a possible role in regulating the oxidative stress response has been suggested for both bacterial and human YchF/Ola1. In this study, we analyzed how YchF responds to oxidative stress and how it potentially regulates the antioxidant response. Results: Our data identify a redox-regulated monomer–dimer equilibrium of YchF as a key event in the functional cycle of YchF. Upon oxidative stress, the oxidation of a conserved and surface-exposed cysteine residue promotes YchF dimerization, which is accompanied by inhibition of the ATPase activity. No dimers were observed in a YchF mutant lacking this cysteine. In vitro, the YchF dimer is dissociated by thioredoxin 1 (TrxA) and this stimulates the ATPase activity. The physiological significance of the YchF-thioredoxin 1 interaction was demonstrated by in vivo cross-linking, which validated this interaction in living cells. This approach also revealed that both the ATPase domain and the helical domain of YchF are in contact with TrxA. Innovation: YchF/Ola1 are the first redox-regulated members of the universally conserved GTPase family and are inactivated by oxidation of a conserved cysteine residue within the nucleotide-binding motif. Conclusion: Our data provide novel insights into the regulation of the so far ill-defined YchF/Ola1 family of proteins and stipulate their role as negative regulators of the oxidative stress response. Antioxid. Redox Signal. 24, 141–156. PMID:26160547

Abscisic Acid Participates in the Control of Cell Cycle Initiation Through Heme Homeostasis in the Unicellular Red Alga Cyanidioschyzon merolae.

PubMed

Kobayashi, Yuki; Ando, Hiroyuki; Hanaoka, Mitsumasa; Tanaka, Kan

2016-05-01

ABA is a phytohormone that is synthesized in response to abiotic stresses and other environmental changes, inducing various physiological responses. While ABA has been found in unicellular photosynthetic organisms, such as cyanobacteria and eukaryotic algae, its function in these organisms is poorly understood. Here, we found that ABA accumulated in the unicellular red alga Cyanidioschyzon merolae under conditions of salt stress and that the cell cycle G1/S transition was inhibited when ABA was added to the culture medium. A gene encoding heme-scavenging tryptophan-rich sensory protein-related protein (CmTSPO; CMS231C) was positively regulated by ABA, as in Arabidopsis, and CmTSPO bound heme in vitro. The intracellular content of total heme was increased by addition of ABA, but unfettered heme decreased, presumably due to scavenging by CmTSPO. The inhibition of DNA replication by ABA was negated by addition of heme to the culture medium. Thus, we propose a regulatory role for ABA and heme in algal cell cycle initiation. Finally, we found that a C. merolae mutant that is defective in ABA production was more susceptible to salt stress, indicating the importance of ABA to stress resistance in red algae. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Microarray-based transcriptome of Listeria monocytogenes adapted to sublethal concentrations of acetic acid, lactic acid, and hydrochloric acid.

PubMed

Tessema, Girum Tadesse; Møretrø, Trond; Snipen, Lars; Heir, Even; Holck, Askild; Naterstad, Kristine; Axelsson, Lars

2012-09-01

Listeria monocytogenes , an important foodborne pathogen, commonly encounters organic acids in food-related environments. The transcriptome of L. monocytogenes L502 was analyzed after adaptation to pH 5 in the presence of acetic acid, lactic acid, or hydrochloric acid (HCl) at 25 °C, representing a condition encountered in mildly acidic ready-to-eat food kept at room temperature. The acid-treated cells were compared with a reference culture with a pH of 6.7 at the time of RNA harvesting. The number of genes and magnitude of transcriptional responses were higher for the organic acids than for HCl. Protein coding genes described for low pH stress, energy transport and metabolism, virulence determinates, and acid tolerance response were commonly regulated in the 3 acid-stressed cultures. Interestingly, the transcriptional levels of histidine and cell wall biosynthetic operons were upregulated, indicating possible universal response against low pH stress in L. monocytogenes. The opuCABCD operon, coding proteins for compatible solutes transport, and the transcriptional regulator sigL were significantly induced in the organic acids, strongly suggesting key roles during organic acid stress. The present study revealed the complex transcriptional responses of L. monocytogenes towards food-related acidulants and opens the roadmap for more specific and in-depth future studies.

Extracellular cell stress (heat shock) proteins-immune responses and disease: an overview.

PubMed

Pockley, A Graham; Henderson, Brian

2018-01-19

Extracellular cell stress proteins are highly conserved phylogenetically and have been shown to act as powerful signalling agonists and receptors for selected ligands in several different settings. They also act as immunostimulatory 'danger signals' for the innate and adaptive immune systems. Other studies have shown that cell stress proteins and the induction of immune reactivity to self-cell stress proteins can attenuate disease processes. Some proteins (e.g. Hsp60, Hsp70, gp96) exhibit both inflammatory and anti-inflammatory properties, depending on the context in which they encounter responding immune cells. The burgeoning literature reporting the presence of stress proteins in a range of biological fluids in healthy individuals/non-diseased settings, the association of extracellular stress protein levels with a plethora of clinical and pathological conditions and the selective expression of a membrane form of Hsp70 on cancer cells now supports the concept that extracellular cell stress proteins are involved in maintaining/regulating organismal homeostasis and in disease processes and phenotype. Cell stress proteins, therefore, form a biologically complex extracellular cell stress protein network having diverse biological, homeostatic and immunomodulatory properties, the understanding of which offers exciting opportunities for delivering novel approaches to predict, identify, diagnose, manage and treat disease.This article is part of the theme issue 'Heat shock proteins as modulators and therapeutic targets of chronic disease: an integrated perspective'. © 2017 The Author(s).

E3 Ubiquitin Ligase CHIP and NBR1-Mediated Selective Autophagy Protect Additively against Proteotoxicity in Plant Stress Responses

PubMed Central

Qi, Jingxia; Chi, Yingjin; Fan, Baofang; Yu, Jing-Quan; Chen, Zhixiang

2014-01-01

Plant stress responses require both protective measures that reduce or restore stress-inflicted damage to cellular structures and mechanisms that efficiently remove damaged and toxic macromolecules, such as misfolded and damaged proteins. We have recently reported that NBR1, the first identified plant autophagy adaptor with a ubiquitin-association domain, plays a critical role in plant stress tolerance by targeting stress-induced, ubiquitinated protein aggregates for degradation by autophagy. Here we report a comprehensive genetic analysis of CHIP, a chaperone-associated E3 ubiquitin ligase from Arabidopsis thaliana implicated in mediating degradation of nonnative proteins by 26S proteasomes. We isolated two chip knockout mutants and discovered that they had the same phenotypes as the nbr1 mutants with compromised tolerance to heat, oxidative and salt stresses and increased accumulation of insoluble proteins under heat stress. To determine their functional interactions, we generated chip nbr1 double mutants and found them to be further compromised in stress tolerance and in clearance of stress-induced protein aggregates, indicating additive roles of CHIP and NBR1. Furthermore, stress-induced protein aggregates were still ubiquitinated in the chip mutants. Through proteomic profiling, we systemically identified heat-induced protein aggregates in the chip and nbr1 single and double mutants. These experiments revealed that highly aggregate-prone proteins such as Rubisco activase and catalases preferentially accumulated in the nbr1 mutant while a number of light-harvesting complex proteins accumulated at high levels in the chip mutant after a relatively short period of heat stress. With extended heat stress, aggregates for a large number of intracellular proteins accumulated in both chip and nbr1 mutants and, to a greater extent, in the chip nbr1 double mutant. Based on these results, we propose that CHIP and NBR1 mediate two distinct but complementary anti-proteotoxic pathways and protein's propensity to aggregate under stress conditions is one of the critical factors for pathway selection of protein degradation. PMID:24497840

Social Support and Stress among University Students in Jordan

ERIC Educational Resources Information Center

Hamdan-Mansour, Ayman M.; Dawani, Hania A.

2008-01-01

The purpose of this study was to examine the relationship between perception of social support and perceived stress among university students in Jordan. A sample of 241 university students from private and government universities in Jordan answered self-report questionnaires including the perceived social support scale and perceived stress scale.…

Responsive Proteins in Wheat Cultivars with Contrasting Nitrogen Efficiencies under the Combined Stress of High Temperature and Low Nitrogen

PubMed Central

Abd_Allah, Elsayed Fathi; Nauman, Mohd; Asif, Ambreen; Hashem, Abeer; Alqarawi, Abdulaziz A.

2017-01-01

Productivity of wheat (Triticum aestivum) is markedly affected by high temperature and nitrogen deficiency. Identifying the functional proteins produced in response to these multiple stresses acting in a coordinated manner can help in developing tolerance in the crop. In this study, two wheat cultivars with contrasting nitrogen efficiencies (N-efficient VL616 and N-inefficient UP2382) were grown in control conditions, and under a combined stress of high temperature (32 °C) and low nitrogen (4 mM), and their leaf proteins were analysed in order to identify the responsive proteins. Two-dimensional electrophoresis unravelled sixty-one proteins, which varied in their expression in wheat, and were homologous to known functional proteins involved in biosynthesis, carbohydrate metabolism, energy metabolism, photosynthesis, protein folding, transcription, signalling, oxidative stress, water stress, lipid metabolism, heat stress tolerance, nitrogen metabolism, and protein synthesis. When exposed to high temperature in combination with low nitrogen, wheat plants altered their protein expression as an adaptive means to maintain growth. This response varied with cultivars. Nitrogen-efficient cultivars showed a higher potential of redox homeostasis, protein stability, osmoprotection, and regulation of nitrogen levels. The identified stress-responsive proteins can pave the way for enhancing the multiple-stress tolerance in wheat and developing a better understanding of its mechanism. PMID:29186028

Acute Heat Stress Changes Protein Expression in the Testes of a Broiler-Type Strain of Taiwan Country Chickens.

PubMed

Wang, Shih-Han; Cheng, Chuen-Yu; Chen, Chao-Jung; Chan, Hong-Lin; Chen, Hsin-Hsin; Tang, Pin-Chi; Chen, Chih-Feng; Lee, Yen-Pai; Huang, San-Yuan

2018-03-19

Heat stress leads to decreased fertility in roosters. This study investigated the global protein expression in response to acute heat stress in the testes of a broiler-type strain of Taiwan country chickens (TCCs). Twelve 45-week-old roosters were randomly allocated to the control group maintained at 25°C, and three groups subjected to acute heat stress at 38°C for 4 h, with 0, 2, and 6 h of recovery, respectively. Testis samples were collected for hematoxylin and eosin staining, apoptosis assay, and protein analysis. The results revealed 101 protein spots that differed significantly from the control following exposure to acute heat stress. The proteins that were differentially expressed participated mainly in protein metabolism and other metabolic processes, responses to stimuli, apoptosis, cellular organization, and spermatogenesis. Proteins that negatively regulate apoptosis were downregulated and proteins involved in autophagy and major heat shock proteins (HSP90α, HSPA5, and HSPA8) were upregulated in the testes of heat-stressed chickens. In conclusion, acute heat stress causes a change in protein expression in the testes of broiler-type B strain TCCs and may thus impair cell morphology, spermatogenesis, and apoptosis. The expression of heat shock proteins increased to attenuate the testicular injury induced by acute heat stress.

Proteomic analysis of Chromobacterium violaceum and its adaptability to stress.

PubMed

Castro, Diogo; Cordeiro, Isabelle Bezerra; Taquita, Paula; Eberlin, Marcos Nogueira; Garcia, Jerusa Simone; Souza, Gustavo Henrique M F; Arruda, Marco Aurélio Zezzi; Andrade, Edmar V; Filho, Spartaco A; Crainey, J Lee; Lozano, Luis Lopez; Nogueira, Paulo A; Orlandi, Patrícia P

2015-12-01

Chromobacterium violaceum (C. violaceum) occurs abundantly in a variety of ecosystems, including ecosystems that place the bacterium under stress. This study assessed the adaptability of C. violaceum by submitting it to nutritional and pH stresses and then analyzing protein expression using bi-dimensional electrophoresis (2-DE) and Maldi mass spectrometry. Chromobacterium violaceum grew best in pH neutral, nutrient-rich medium (reference conditions); however, the total protein mass recovered from stressed bacteria cultures was always higher than the total protein mass recovered from our reference culture. The diversity of proteins expressed (repressed by the number of identifiable 2-DE spots) was seen to be highest in the reference cultures, suggesting that stress reduces the overall range of proteins expressed by C. violaceum. Database comparisons allowed 43 of the 55 spots subjected to Maldi mass spectrometry to be characterized as containing a single identifiable protein. Stress-related expression changes were noted for C. violaceum proteins related to the previously characterized bacterial proteins: DnaK, GroEL-2, Rhs, EF-Tu, EF-P; MCP, homogentisate 1,2-dioxygenase, Arginine deiminase and the ATP synthase β-subunit protein as well as for the ribosomal protein subunits L1, L3, L5 and L6. The ability of C. violaceum to adapt its cellular mechanics to sub-optimal growth and protein production conditions was well illustrated by its regulation of ribosomal protein subunits. With the exception of the ribosomal subunit L3, which plays a role in protein folding and maybe therefore be more useful in stressful conditions, all the other ribosomal subunit proteins were seen to have reduced expression in stressed cultures. Curiously, C. violeaceum cultures were also observed to lose their violet color under stress, which suggests that the violacein pigment biosynthetic pathway is affected by stress. Analysis of the proteomic signatures of stressed C. violaceum indicates that nutrient-starvation and pH stress can cause changes in the expression of the C. violaceum receptors, transporters, and proteins involved with biosynthetic pathways, molecule recycling, energy production. Our findings complement the recent publication of the C. violeaceum genome sequence and could help with the future commercial exploitation of C. violeaceum.

Changes in translation rate modulate stress-induced damage of diverse proteins

PubMed Central

Kim, Heejung

2013-01-01

Proteostasis is the maintenance of the proper function of cellular proteins. Hypertonic stress disrupts proteostasis and causes rapid and widespread protein aggregation and misfolding in the nematode Caenorhabditis elegans. Optimal survival in hypertonic environments requires degradation of damaged proteins. Inhibition of protein synthesis occurs in response to diverse environmental stressors and may function in part to minimize stress-induced protein damage. We recently tested this idea directly and demonstrated that translation inhibition by acute exposure to cycloheximide suppresses hypertonicity-induced aggregation of polyglutamine::YFP (Q35::YFP) in body wall muscle cells. In this article, we further characterized the relationship between protein synthesis and hypertonic stress-induced protein damage. We demonstrate that inhibition of translation reduces hypertonic stress-induced formation and growth of Q35::YFP, Q44::YFP, and α-synuclein aggregates; misfolding of paramyosin and ras GTPase; and aggregation of multiple endogenous proteins expressed in diverse cell types. Activation of general control nonderepressible-2 (GCN-2) kinase signaling during hypertonic stress inhibits protein synthesis via phosphorylation of eukaryotic initiation factor-2α (eIF-2α). Inhibition of GCN-2 activation prevents the reduction in translation rate and greatly exacerbates the formation and growth of Q35::YFP aggregates and the aggregation of endogenous proteins. The current studies together with our previous work provide the first direct demonstration that hypertonic stress-induced reduction in protein synthesis minimizes protein aggregation and misfolding. Reduction in translation rate also serves as a signal that activates osmoprotective gene expression. The cellular proteostasis network thus plays a critical role in minimizing hypertonic stress-induced protein damage, in degrading stress-damaged proteins, and in cellular osmosensing and signaling. PMID:24153430

Proteomic analysis of Arabidopsis thaliana leaves in response to acute boron deficiency and toxicity reveals effects on photosynthesis, carbohydrate metabolism, and protein synthesis.

PubMed

Chen, Mei; Mishra, Sasmita; Heckathorn, Scott A; Frantz, Jonathan M; Krause, Charles

2014-02-15

Boron (B) stress (deficiency and toxicity) is common in plants, but as the functions of this essential micronutrient are incompletely understood, so too are the effects of B stress. To investigate mechanisms underlying B stress, we examined protein profiles in leaves of Arabidopsis thaliana plants grown under normal B (30 μM), compared to plants transferred for 60 and 84 h (i.e., before and after initial visible symptoms) in deficient (0 μM) or toxic (3 mM) levels of B. B-responsive polypeptides were sequenced by mass spectrometry, following 2D gel electrophoresis, and 1D gels and immunoblotting were used to confirm the B-responsiveness of some of these proteins. Fourteen B-responsive proteins were identified, including: 9 chloroplast proteins, 6 proteins of photosynthetic/carbohydrate metabolism (rubisco activase, OEC23, photosystem I reaction center subunit II-1, ATPase δ-subunit, glycolate oxidase, fructose bisphosphate aldolase), 6 stress proteins, and 3 proteins involved in protein synthesis (note that the 14 proteins may fall into multiple categories). Most (8) of the B-responsive proteins decreased under both B deficiency and toxicity; only 3 increased with B stress. Boron stress decreased, or had no effect on, 3 of 4 oxidative stress proteins examined, and did not affect total protein. Hence, our results indicate relatively early specific effects of B stress on chloroplasts and protein synthesis. Copyright © 2013 Elsevier GmbH. All rights reserved.

RAN1 is involved in plant cold resistance and development in rice (Oryza sativa).

PubMed

Xu, Peipei; Cai, Weiming

2014-07-01

Of the diverse abiotic stresses, low temperature is one of the major limiting factors that lead to a series of morphological, physiological, biochemical, and molecular changes in plants. Ran, an evolutionarily conserved small G-protein family, has been shown to be essential for the nuclear translocation of proteins. It also mediates the regulation of cell cycle progression in mammalian cells. However, little is known about Ran function in rice (Oryza sativa). We report here that Ran gene OsRAN1 is essential for the molecular improvement of rice for cold tolerance. Ran also affects plant morphogenesis in transgenic Arabidopsis thaliana. OsRAN1 is ubiquitously expressed in rice tissues with the highest expression in the spike. The levels of mRNA encoding OsRAN1 were greatly increased by cold and indoleacetic acid treatment rather than by addition of salt and polyethylene glycol. Further, OsRAN1 overexpression in Arabidopsis increased tiller number, and altered root development. OsRAN1 overexpression in rice improves cold tolerance. The levels of cellular free Pro and sugar levels were highly increased in transgenic plants under cold stress. Under cold stress, OsRAN1 maintained cell division and cell cycle progression, and also promoted the formation of an intact nuclear envelope. The results suggest that OsRAN1 protein plays an important role in the regulation of cellular mitosis and the auxin signalling pathway. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

An arginine-rich motif of ring finger protein 4 (RNF4) oversees the recruitment and degradation of the phosphorylated and SUMOylated Krüppel-associated box domain-associated protein 1 (KAP1)/TRIM28 protein during genotoxic stress.

PubMed

Kuo, Ching-Ying; Li, Xu; Kong, Xiang-Qian; Luo, Cheng; Chang, Che-Chang; Chung, Yiyin; Shih, Hsiu-Ming; Li, Keqin Kathy; Ann, David K

2014-07-25

Krüppel-associated box domain-associated protein 1 (KAP1) is a universal transcriptional corepressor that undergoes multiple posttranslational modifications (PTMs), including SUMOylation and Ser-824 phosphorylation. However, the functional interplay of KAP1 PTMs in regulating KAP1 turnover during DNA damage response remains unclear. To decipher the role and cross-talk of multiple KAP1 PTMs, we show here that DNA double strand break-induced KAP1 Ser-824 phosphorylation promoted the recruitment of small ubiquitin-like modifier (SUMO)-targeted ubiquitin E3 ligase, ring finger protein 4 (RNF4), and subsequent RNF4-mediated, SUMO-dependent degradation. Besides the SUMO interacting motif (SIM), a previously unrecognized, but evolutionarily conserved, arginine-rich motif (ARM) in RNF4 acts as a novel recognition motif for selective target recruitment. Results from combined mutagenesis and computational modeling studies suggest that RNF4 utilizes concerted bimodular recognition, namely SIM for Lys-676 SUMOylation and ARM for Ser(P)-824 of simultaneously phosphorylated and SUMOylated KAP1 (Ser(P)-824-SUMO-KAP1). Furthermore, we proved that arginines 73 and 74 within the ARM of RNF4 are required for efficient recruitment to KAP1 or accelerated degradation of promyelocytic leukemia protein (PML) under stress. In parallel, results of bimolecular fluorescence complementation assays validated the role of the ARM in recognizing Ser(P)-824 in living cells. Taken together, we establish that the ARM is required for RNF4 to efficiently target Ser(P)-824-SUMO-KAP1, conferring ubiquitin Lys-48-mediated proteasomal degradation in the context of double strand breaks. The conservation of such a motif may possibly explain the requirement for timely substrate selectivity determination among a myriad of SUMOylated proteins under stress conditions. Thus, the ARM dynamically regulates the SIM-dependent recruitment of targets to RNF4, which could be critical to dynamically fine-tune the abundance of Ser(P)-824-SUMO-KAP1 and, potentially, other SUMOylated proteins during DNA damage response. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

An Arginine-rich Motif of Ring Finger Protein 4 (RNF4) Oversees the Recruitment and Degradation of the Phosphorylated and SUMOylated Krüppel-associated Box Domain-associated Protein 1 (KAP1)/TRIM28 Protein during Genotoxic Stress*

PubMed Central

Kuo, Ching-Ying; Li, Xu; Kong, Xiang-Qian; Luo, Cheng; Chang, Che-Chang; Chung, Yiyin; Shih, Hsiu-Ming; Li, Keqin Kathy; Ann, David K.

2014-01-01

Krüppel-associated box domain-associated protein 1 (KAP1) is a universal transcriptional corepressor that undergoes multiple posttranslational modifications (PTMs), including SUMOylation and Ser-824 phosphorylation. However, the functional interplay of KAP1 PTMs in regulating KAP1 turnover during DNA damage response remains unclear. To decipher the role and cross-talk of multiple KAP1 PTMs, we show here that DNA double strand break-induced KAP1 Ser-824 phosphorylation promoted the recruitment of small ubiquitin-like modifier (SUMO)-targeted ubiquitin E3 ligase, ring finger protein 4 (RNF4), and subsequent RNF4-mediated, SUMO-dependent degradation. Besides the SUMO interacting motif (SIM), a previously unrecognized, but evolutionarily conserved, arginine-rich motif (ARM) in RNF4 acts as a novel recognition motif for selective target recruitment. Results from combined mutagenesis and computational modeling studies suggest that RNF4 utilizes concerted bimodular recognition, namely SIM for Lys-676 SUMOylation and ARM for Ser(P)-824 of simultaneously phosphorylated and SUMOylated KAP1 (Ser(P)-824-SUMO-KAP1). Furthermore, we proved that arginines 73 and 74 within the ARM of RNF4 are required for efficient recruitment to KAP1 or accelerated degradation of promyelocytic leukemia protein (PML) under stress. In parallel, results of bimolecular fluorescence complementation assays validated the role of the ARM in recognizing Ser(P)-824 in living cells. Taken together, we establish that the ARM is required for RNF4 to efficiently target Ser(P)-824-SUMO-KAP1, conferring ubiquitin Lys-48-mediated proteasomal degradation in the context of double strand breaks. The conservation of such a motif may possibly explain the requirement for timely substrate selectivity determination among a myriad of SUMOylated proteins under stress conditions. Thus, the ARM dynamically regulates the SIM-dependent recruitment of targets to RNF4, which could be critical to dynamically fine-tune the abundance of Ser(P)-824-SUMO-KAP1 and, potentially, other SUMOylated proteins during DNA damage response. PMID:24907272

Quantitative proteomics reveals the effect of protein glycosylation in soybean root under flooding stress

PubMed Central

Mustafa, Ghazala; Komatsu, Setsuko

2014-01-01

Flooding stress has a negative impact on soybean cultivation because it severely impairs growth and development. To understand the flooding responsive mechanism in early stage soybeans, a glycoproteomic technique was used. Two-day-old soybeans were treated with flooding for 2 days and roots were collected. Globally, the accumulation level of glycoproteins, as revealed by cross-reaction with concanavalin A decreased by 2 days of flooding stress. Glycoproteins were enriched from total protein extracts using concanavalin A lectin resin and analyzed using a gel-free proteomic technique. One-hundred eleven and 69 glycoproteins were identified without and with 2 days of flooding stress, respectively. Functional categorization of these identified glycoproteins indicated that the accumulation level of proteins related to protein degradation, cell wall, and glycolysis increased, while stress-related proteins decreased under flooding stress. Also the accumulation level of glycoproteins localized in the secretory pathway decreased under flooding stress. Out of 23 common glycoproteins between control and flooding conditions, peroxidases and glycosyl hydrolases were decreased by 2 days of flooding stress. mRNA expression levels of proteins in the endoplasmic reticulum and N-glycosylation related proteins were downregulated by flooding stress. These results suggest that flooding might negatively affect the process of N-glycosylation of proteins related to stress and protein degradation; however glycoproteins involved in glycolysis are activated. PMID:25477889

Royal Jelly-Mediated Prolongevity and Stress Resistance in Caenorhabditis elegans Is Possibly Modulated by the Interplays of DAF-16, SIR-2.1, HCF-1, and 14-3-3 Proteins.

PubMed

Wang, Xiaoxia; Cook, Lauren F; Grasso, Lindsay M; Cao, Min; Dong, Yuqing

2015-07-01

Recent studies suggest that royal jelly (RJ) and its related substances may have antiaging properties. However, the molecular mechanisms underlying the beneficial effects remain elusive. We report that the effects of RJ and enzyme-treated RJ (eRJ) on life span and health span in Caenorhabditis elegans (C elegans) are modulated by the sophisticated interplays of DAF-16, SIR-2.1, HCF-1, and 14-3-3 proteins. Dietary supplementation with RJ or eRJ increased C. elegans life span in a dose-dependent manner. The RJ and eRJ consumption increased the tolerance of C elegans to oxidative stress, ultraviolet irradiation, and heat shock stress. Our genetic analyses showed that RJ/eRJ-mediated life-span extension requires insulin/IGF-1 signaling and the activities of DAF-16, SIR-2.1, HCF-1, and FTT-2, a 14-3-3 protein. Earlier studies reported that DAF-16/FOXO, SIR-2.1/SIRT1, FTT-2, and HCF-1 have extensive interplays in worms and mammals. Our present findings suggest that RJ/eRJ-mediated promotion of longevity and stress resistance in C elegans is dependent on these conserved interplays. From an evolutionary point of view, this study not only provides new insights into the molecular mechanisms of RJ's action on health span promotion in C elegans, but also has imperative implications in using RJ/eRJ as nutraceuticals to delay aging and age-related disorders. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Stressing Academia? Stress-as-Offence-to-Self at Danish Universities

ERIC Educational Resources Information Center

Opstrup, Niels; Pihl-Thingvad, Signe

2016-01-01

Academic work has traditionally been seen as relatively stress free. However, a growing number of studies have reported increases in occupational stress experienced by university researchers. In order to explain stress among this group, we build on a new perspective in occupational stress research: the so-called stress-as-offence-to-self…

Nuclear Proteomics Reveals the Role of Protein Synthesis and Chromatin Structure in Root Tip of Soybean during the Initial Stage of Flooding Stress.

PubMed

Yin, Xiaojian; Komatsu, Setsuko

2016-07-01

To identify the upstream events controlling the regulation of flooding-responsive proteins in soybean, proteomic analysis of nuclear proteins in root tip was performed. By using nuclear fractions, which were highly enriched, a total of 365 nuclear proteins were changed in soybean root tip at initial stage of flooding stress. Four exon-junction complex-related proteins and NOP1/NOP56, which function in upstream of 60S preribosome biogenesis, were decreased in flooded soybean. Furthermore, proteomic analysis of crude protein extract revealed that the protein translation was suppressed by continuous flooding stress. Seventeen chromatin structure-related nuclear proteins were decreased in response to flooding stress. Out of them, histone H3 was clearly decreased with protein abundance and mRNA expression levels at the initial flooding stress. Additionally, a number of protein synthesis-, RNA-, and DNA-related nuclear proteins were decreased in a time-dependent manner. mRNA expressions of genes encoding the significantly changed flooding-responsive nuclear proteins were inhibited by the transcriptional inhibitor, actinomycin D. These results suggest that protein translation is suppressed through inhibition of preribosome biogenesis- and mRNA processing-related proteins in nuclei of soybean root tip at initial flooding stress. In addition, flooding stress may regulate histone variants with gene expression in root tip.

A Causal Relationship of Occupational Stress among University Employees.

PubMed

Kaewanuchit, Chonticha; Muntaner, Carles; Isha, Nizam

2015-07-01

Occupational stress is a psychosocial dimension of occupational health concept on social determinants of health, especially, job & environmental condition. Recently, staff network of different government universities of Thailand have called higher education commission, and Ministry of Education, Thailand to resolve the issue of government education policy (e.g. wage inequity, poor welfare, law, and job & environment condition) that leads to their job insecurity, physical and mental health problems from occupational stress. The aim of this study was to investigate a causal relationship of occupational stress among the academic university employees. This cross sectional research was conducted in 2014 among 2,000 academic university employees at Thai government universities using stratified random sampling. Independent variables were wage, family support, periods of duty, and job & environmental condition. Dependent variable was stress. Job & environmental condition, as social and environmental factor, and periods of duty as individual factor had direct effect to stress (P< 0.05). Family support, as family factor, and wage, as individual factor had direct effect to stress (P < 0.05). Both family support and wage were the causal endogenous variables. Job & environmental condition and periods of duty were increased so that it associated with occupational stress among academic university employees at moderate level.

Proteomic and physiological analyses reveal the role of exogenous spermidine on cucumber roots in response to Ca(NO3)2 stress.

PubMed

Du, Jing; Guo, Shirong; Sun, Jin; Shu, Sheng

2018-05-01

The mechanism of exogenous Spd-induced Ca(NO 3 ) 2 stress tolerance in cucumber was studied by proteomics and physiological analyses. Protein-protein interaction network revealed 13 key proteins involved in Spd-induced Ca(NO 3 ) 2 stress resistance. Ca(NO 3 ) 2 stress is one of the major reasons for secondary salinization that limits cucumber plant development in greenhouse. The conferred protective role of exogenous Spd on cucumber in response to Ca(NO 3 ) 2 stress cues involves changes at the cellular and physiological levels. To investigate the molecular foundation of exogenous Spd in Ca(NO 3 ) 2 stress tolerance, a proteomic approach was performed in our work. After a 9 days period of Ca(NO 3 ) 2 stress and/or exogenous Spd, 71 differential protein spots were confidently identified. The resulting proteins were enriched in seven different categories of biological processes, including protein metabolism, carbohydrate and energy metabolism, ROS homeostasis and stress defense, cell wall related, transcription, others and unknown. Protein metabolism (31.2%), carbohydrate and energy metabolism (15.6%), ROS homeostasis and stress defense (32.5%) were the three largest functional categories in cucumber root and most of them were significantly increased by exogenous Spd. The Spd-responsive protein interaction network revealed 13 key proteins, whose accumulation changes could be critical for Spd-induced resistance; all 13 proteins were upregulated by Spd at transcriptional and protein levels in response to Ca(NO 3 ) 2 stress. Furthermore, accumulation of antioxidant enzymes, non-enzymatic antioxidant and polyamines, along with reduction of H 2 O 2 and MDA, were detected after exogenous Spd application during Ca(NO 3 ) 2 stress. The results of these proteomic and physiological analyses in cucumber root may facilitate a better understanding of the underlying mechanism of Ca(NO 3 ) 2 stress tolerance mediated by exogenous Spd.

Intracellular proteins produced by mammalian cells in response to environmental stress

NASA Technical Reports Server (NTRS)

Goochee, Charles F.; Passini, Cheryl A.

1988-01-01

The nature of the response of mammalian cells to environmental stress is examined by reviewing results of studies where cultured mouse L cells and baby hamster kidney cells were exposed to heat shock and the synthesis of heat-shock proteins and stress-response proteins (including HSP70, HSC70, HSP90, ubiquitin, and GRP70) in stressed and unstressed cells was evaluated using 2D-PAGE. The intracellular roles of the individual stress response proteins are discussed together with the regulation of the stress response system.

Protein-bound uraemic toxins, dicarbonyl stress and advanced glycation end products in conventional and extended haemodialysis and haemodiafiltration.

PubMed

Cornelis, Tom; Eloot, Sunny; Vanholder, Raymond; Glorieux, Griet; van der Sande, Frank M; Scheijen, Jean L; Leunissen, Karel M; Kooman, Jeroen P; Schalkwijk, Casper G

2015-08-01

Protein-bound uraemic toxins (PBUT), dicarbonyl stress and advanced glycation end products (AGEs) associate with cardiovascular disease in dialysis. Intensive haemodialysis (HD) may have significant clinical benefits. The aim of this study was to evaluate the acute effects of conventional and extended HD and haemodiafiltration (HDF) on reduction ratio (RR) and total solute removal (TSR) of PBUT, dicarbonyl stress compounds and AGEs. Thirteen stable conventional HD patients randomly completed a single study of 4-h HD (HD4), 4-h HDF (HDF4), 8-h HD (HD8) and 8-h HDF (HDF8) with a 2-week interval between the study sessions. RR and TSR of PBUT [indoxyl sulphate (IS), p-cresyl sulphate (PCS), p-cresyl glucuronide, 3-carboxyl-4-methyl-5-propyl-2-furanpropionic acid (CMPF), indole-3-acetic acid (IAA) and hippuric acid] of free and protein-bound AGEs [N(ε)-(carboxymethyl)lysine (CML), N(ε)-(carboxyethyl)lysine (CEL), Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine, pentosidine], as well as of dicarbonyl compounds [glyoxal, methylglyoxal, 3-deoxyglucosone], were determined. Compared with HD4, HDF4 resulted in increased RR of total and/or free fractions of IAA and IS as well as increased RR of free CML and CEL. HD8 and HDF8 showed a further increase in TSR and RR of PBUT (except CMPF), as well as of dicarbonyl stress and free AGEs compared with HD4 and HDF4. Compared with HD8, HDF8 only significantly increased RR of total and free IAA and free PCS, as well as RR of free CEL. Dialysis time extension (HD8 and HDF8) optimized TSR and RR of PBUT, dicarbonyl stress and AGEs, whereas HDF8 was superior to HD8 for only a few compounds. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Proteomic Profiling of the Interactions of Cd/Zn in the Roots of Dwarf Polish Wheat (Triticum polonicum L.)

PubMed Central

Wang, Yi; Wang, Xiaolu; Wang, Chao; Wang, Ruijiao; Peng, Fan; Xiao, Xue; Zeng, Jian; Fan, Xing; Kang, Houyang; Sha, Lina; Zhang, Haiqin; Zhou, Yonghong

2016-01-01

Cd and Zn have been shown to interact antagonistically or synergistically in various plants. In the present study of dwarf polish wheat (DPW)roots, Cd uptake was inhibited by Zn, and Zn uptake was inhibited by Cd, suggesting that Cd and Zn interact antagonistically in this plant. A study of proteomic changes showed that Cd, Zn, and Cd+Zn stresses altered the expression of 206, 303, and 190 proteins respectively. Among these, 53 proteins were altered significantly in response to all these stresses (Cd, Zn, and Cd+Zn), whereas 58, 131, and 47 proteins were altered in response to individual stresses (Cd, Zn, and Cd+Zn, respectively). Sixty-one differentially expressed proteins (DEPs) were induced in response to both Cd and Zn stresses; 33 proteins were induced in response to both Cd and Cd+Zn stresses; and 57 proteins were induced in response to both Zn and Cd+Zn stresses. These results indicate that Cd and Zn induce differential molecular responses, which result in differing interactions of Cd/Zn. A number of proteins that mainly participate in oxidation-reduction and GSH, SAM, and sucrose metabolisms were induced in response to Cd stress, but not Cd+Zn stress. This result indicates that these proteins participate in Zn inhibition of Cd uptake and ultimately cause Zn detoxification of Cd. Meanwhile, a number of proteins that mainly participate in sucrose and organic acid metabolisms and oxidation-reduction were induced in response to Zn stress but not Cd+Zn stress. This result indicates that these proteins participate in Cd inhibition of Zn uptake and ultimately cause the Cd detoxification of Zn. Other proteins induced in response to Cd, Zn, or Cd+Zn stress, participate in ribosome biogenesis, DNA metabolism, and protein folding/modification and may also participate in the differential defense mechanisms. PMID:27683584

Proteome Analysis for Understanding Abiotic Stress (Salinity and Drought) Tolerance in Date Palm (Phoenix dactylifera L.).

PubMed

El Rabey, Haddad A; Al-Malki, Abdulrahman L; Abulnaja, Khalid O; Rohde, Wolfgang

2015-01-01

This study was carried out to study the proteome of date palm under salinity and drought stress conditions to possibly identify proteins involved in stress tolerance. For this purpose, three-month-old seedlings of date palm cultivar "Sagie" were subjected to drought (27.5 g/L polyethylene glycol 6000) and salinity stress conditions (16 g/L NaCl) for one month. DIGE analysis of protein extracts identified 47 differentially expressed proteins in leaves of salt- and drought-treated palm seedlings. Mass spectrometric analysis identified 12 proteins; three out of them were significantly changed under both salt and drought stress, while the other nine were significantly changed only in salt-stressed plants. The levels of ATP synthase alpha and beta subunits, an unknown protein and some of RubisCO fragments were significantly changed under both salt and drought stress conditions. Changes in abundance of superoxide dismutase, chlorophyll A-B binding protein, light-harvesting complex1 protein Lhca1, RubisCO activase, phosphoglycerate kinase, chloroplast light-harvesting chlorophyll a/b-binding protein, phosphoribulokinase, transketolase, RubisCO, and some of RubisCO fragments were significant only for salt stress.

Biochemical analysis of 'kerosene tree' Hymenaea courbaril L. under heat stress.

PubMed

Gupta, Dinesh; Eldakak, Moustafa; Rohila, Jai S; Basu, Chhandak

2014-01-01

Hymenaea courbaril or jatoba is a tropical tree known for its medically important secondary metabolites production. Considering climate change, the goal of this study was to investigate differential expression of proteins and lipids produced by this tree under heat stress conditions. Total lipid was extracted from heat stressed plant leaves and various sesquiterpenes produced by the tree under heat stress were identified. Gas chromatographic and mass spectrometric analysis were used to study lipid and volatile compounds produced by the plant. Several volatiles, isoprene, 2-methyl butanenitrile, β ocimene and a numbers of sesquiterpenes differentially produced by the plant under heat stress were identified. We propose these compounds were produced by the tree to cope up with heat stress. A protein gel electrophoresis (2-D DIGE) was performed to study differential expression of proteins in heat stressed plants. Several proteins were found to be expressed many folds different in heat stressed plants compared to the control. These proteins included heat shock proteins, histone proteins, oxygen evolving complex, and photosynthetic proteins, which, we believe, played key roles in imparting thermotolerance in Hymenaea tree. To the best of our knowledge, this is the first report of extensive molecular physiological study of Hymenaea trees under heat stress. This work will open avenues of further research on effects of heat stress in Hymenaea and the findings can be applied to understand how global warming can affect physiology of other plants.

Strain-enhanced stress relaxation impacts nonlinear elasticity in collagen gels

PubMed Central

Nam, Sungmin; Hu, Kenneth H.; Chaudhuri, Ovijit

2016-01-01

The extracellular matrix (ECM) is a complex assembly of structural proteins that provides physical support and biochemical signaling to cells in tissues. The mechanical properties of the ECM have been found to play a key role in regulating cell behaviors such as differentiation and malignancy. Gels formed from ECM protein biopolymers such as collagen or fibrin are commonly used for 3D cell culture models of tissue. One of the most striking features of these gels is that they exhibit nonlinear elasticity, undergoing strain stiffening. However, these gels are also viscoelastic and exhibit stress relaxation, with the resistance of the gel to a deformation relaxing over time. Recent studies have suggested that cells sense and respond to both nonlinear elasticity and viscoelasticity of ECM, yet little is known about the connection between nonlinear elasticity and viscoelasticity. Here, we report that, as strain is increased, not only do biopolymer gels stiffen but they also exhibit faster stress relaxation, reducing the timescale over which elastic energy is dissipated. This effect is not universal to all biological gels and is mediated through weak cross-links. Mechanistically, computational modeling and atomic force microscopy (AFM) indicate that strain-enhanced stress relaxation of collagen gels arises from force-dependent unbinding of weak bonds between collagen fibers. The broader effect of strain-enhanced stress relaxation is to rapidly diminish strain stiffening over time. These results reveal the interplay between nonlinear elasticity and viscoelasticity in collagen gels, and highlight the complexity of the ECM mechanics that are likely sensed through cellular mechanotransduction. PMID:27140623

An ABA-responsive DRE-binding protein gene from Setaria italica, SiARDP, the target gene of SiAREB, plays a critical role under drought stress.

PubMed

Li, Cong; Yue, Jing; Wu, Xiaowei; Xu, Cong; Yu, Jingjuan

2014-10-01

The DREB (dehydration-responsive element binding)-type transcription factors regulate the expression of stress-inducible genes by binding the DRE/CRT cis-elements in promoter regions. The upstream transcription factors that regulate the transcription of DREB transcription factors have not been clearly defined, although the function of DREB transcription factors in abiotic stress is known. In this study, an abscisic acid (ABA)-responsive DREB-binding protein gene (SiARDP) was cloned from foxtail millet (Setaria italica). The transcript level of SiARDP increased not only after drought, high salt, and low temperature stresses, but also after an ABA treatment in foxtail millet seedlings. Two ABA-responsive elements (ABRE1: ACGTGTC; ABRE2: ACGTGGC) exist in the promoter of SiARDP. Further analyses showed that two ABA-responsive element binding (AREB)-type transcription factors, SiAREB1 and SiAREB2, could physically bind to the ABRE core element in vitro and in vivo. The constitutive expression of SiARDP in Arabidopsis thaliana enhanced drought and salt tolerance during seed germination and seedling development, and overexpression of SiARDP in foxtail millet improved drought tolerance. The expression levels of target genes of SiARDP were upregulated in transgenic Arabidopsis and foxtail millet. These results reveal that SiARDP, one of the target genes of SiAREB, is involved in ABA-dependent signal pathways and plays a critical role in the abiotic stress response in plants. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Protein glutathionylation protects wheat (Triticum aestivum Var. Sonalika) against Fusarium induced oxidative stress.

PubMed

Mohapatra, Subhalaxmi; Mittra, Bhabatosh

2016-12-01

Fusarium induced oxidative stress could be recovered by reversible protein oxidative modification through the process of glutathionylation in co-stressed (low-dose (50 μM) Cd 2+ pre-treatment followed by Fusarium inoculation) wheat seedlings. Co-stressed seedlings showed low disease severity index as compared to Fusarium infected seedlings. A reduced level of hydrogen peroxide (H 2 O 2 ) and carbonyl contents due to irreversible protein oxidation were observed in co-stressed seedlings as compared to Fusarium infected seedlings. Further, a comparative biochemical assay showed an enhanced glutathione content in co-stressed tissues as compared to Fusarium infected tissues. In an investigation, reduced glutathione pre-coated agarose gel beads were used to pull down proteins having affinity with GSH. Fructose-1, 6-bisphosphate aldolase and 3-Phosphoglycerate kinase were observed to be co-existed in co-stressed seedlings when analysed by LC-MS/MS after being processed through protein-pull assay. Co-stressed tissues showed an enhanced free protein thiol content as compared to Fusarium infected tissues. The ratio of free thiol to thiol disulfides was also observed to be increased in co-stressed tissues as compared to Fusarium infected tissues. In contrast, the quantitative assay by Ellman's reagent and qualitative analysis by diagonal gel electrophoresis showed enhanced protein thiol disulfides in Fusarium infected tissues as compared to co-stressed tissues. Further, glutaredoxin, responsible for the reverse reduction of proteins was observed to be enhanced in co-stressed tissues as compared to Fusarium infected tissues. Thus, a low dose Cd 2+ triggered glutathionylation is suggestive of offering tolerance against Fusarium induced oxidative stress and protects target proteins from irreversible modification and permanent damage in wheat. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Stress proteins and the immune response.

PubMed

Moseley, P

2000-07-25

The heat shock or stress response is one of the most highly conserved adaptive responses in nature. In single cell organisms, the stress response confers tolerance to a variety of stresses including hyperthermia, hyperoxia, hypoxia, and other perturbations, which alter protein synthesis. This tolerance phenomenon is also extremely important in the multicellular organism, resulting in not only thermal tolerance, but also resistance to stresses of the whole organism such as ischemia-reperfusion injury. Moreover, recent data indicates that these stress proteins have the ability to modulate the cellular immune response. Although the terms heat shock proteins (HSPs) and stress proteins are often used interchangeably, the term stress proteins includes the HSPs, the glucose-regulated proteins (GRPs) and ubiquitin. The stress proteins may be grouped by molecular weight ranging from the large 110 kDa HSP110 to ubiquitin at 8 kDa. These proteins serve as cellular chaperones, participating in protein synthesis and transport through the various cellular compartments. Because these proteins have unique cellular localizations, the chaperone function of the stress proteins often involves a transfer of peptides between stress proteins as the peptide is moved between cellular compartments. For example, HSP70 is a cytosolic and nuclear chaperone, which is critical for the transfer of cellular peptides in the mitochondrion through a hand-off that involves mitochondrial HSP60 at the inner mitochondrial membrane. Similarly, cytosolic proteins are transferred from HSP70 to gp96 as they move into the endoplasmic reticulum. The central role of the stress proteins in the transfer of peptides through the cell may be responsible for the recently recognized importance of the stress proteins in the modulation of the immune system [Feder, M.E., Hofmann, G.E., 1999. Heat-shock proteins, molecular chaperones, and the stress response: evolutionary and ecological physiology. Annu. Rev. Physiol. 61, 243-282.]. This importance in immune regulation is best addressed using Matzinger's model of the immune response - The Danger Theory of Immunity [Matzinger, P., Fuchs, E.J., 1996. Beyond self and non-self: immunity is a conversation, not a war. J. NIH Res. 8, 35-39.]. Matzinger suggests that an immune system model based on the differentiation between "self and non-self" does not easily account for the changes that occur in the organism with growth and development. Why, for example does an organism not self-destruct when the immune system encounters the myriad of new peptides generated at puberty? Instead, she proposes a model of immune function based on the ability to detect and address dangers. This model states that the basic function of all cells of the organism is appropriately timed death "from natural causes". This type of cell death, or apoptosis, generates no stress signals. If, on the other hand, a cell is "murdered" by an infectious agent or dies an untimely death due to necrosis or ischemia, the cell undergoes a stress response with the liberation of stress protein-peptide complexes into the extracellular environment upon cell lysis. Not only do they serve as a "danger signal" to alert the immune system to the death of a cell under stress, but their role as protein carriers allows the immune effector cells to survey the peptides released by this stressed cell and to activate against new or unrecognized peptides carried by the stress protein. Matzinger bases the Danger Theory of Immunity on three "Laws of Lymphotics". These laws state that: (1) resting T lymphocytes require both antigen stimulation by an antigen-presenting cell (APC) and co-stimulation with a danger signal to become activated; (2) the co-stimulatory signal must be received through the APC; and (3) T cells receiving only antigen stimulation without the co-stimulatory signal undergo apoptosis. The Danger Theory gives a simple model for both tolerance and activation. (ABSTRACT TRUNCATED)

WRKY Proteins: Signaling and Regulation of Expression during Abiotic Stress Responses

PubMed Central

Banerjee, Aditya

2015-01-01

WRKY proteins are emerging players in plant signaling and have been thoroughly reported to play important roles in plants under biotic stress like pathogen attack. However, recent advances in this field do reveal the enormous significance of these proteins in eliciting responses induced by abiotic stresses. WRKY proteins act as major transcription factors, either as positive or negative regulators. Specific WRKY factors which help in the expression of a cluster of stress-responsive genes are being targeted and genetically modified to induce improved abiotic stress tolerance in plants. The knowledge regarding the signaling cascade leading to the activation of the WRKY proteins, their interaction with other proteins of the signaling pathway, and the downstream genes activated by them are altogether vital for justified targeting of the WRKY genes. WRKY proteins have also been considered to generate tolerance against multiple abiotic stresses with possible roles in mediating a cross talk between abiotic and biotic stress responses. In this review, we have reckoned the diverse signaling pattern and biological functions of WRKY proteins throughout the plant kingdom along with the growing prospects in this field of research. PMID:25879071

WRKY proteins: signaling and regulation of expression during abiotic stress responses.

PubMed

Banerjee, Aditya; Roychoudhury, Aryadeep

2015-01-01

WRKY proteins are emerging players in plant signaling and have been thoroughly reported to play important roles in plants under biotic stress like pathogen attack. However, recent advances in this field do reveal the enormous significance of these proteins in eliciting responses induced by abiotic stresses. WRKY proteins act as major transcription factors, either as positive or negative regulators. Specific WRKY factors which help in the expression of a cluster of stress-responsive genes are being targeted and genetically modified to induce improved abiotic stress tolerance in plants. The knowledge regarding the signaling cascade leading to the activation of the WRKY proteins, their interaction with other proteins of the signaling pathway, and the downstream genes activated by them are altogether vital for justified targeting of the WRKY genes. WRKY proteins have also been considered to generate tolerance against multiple abiotic stresses with possible roles in mediating a cross talk between abiotic and biotic stress responses. In this review, we have reckoned the diverse signaling pattern and biological functions of WRKY proteins throughout the plant kingdom along with the growing prospects in this field of research.

Vapb/Amyotrophic lateral sclerosis 8 knock-in mice display slowly progressive motor behavior defects accompanying ER stress and autophagic response.

PubMed

Larroquette, Frédérique; Seto, Lesley; Gaub, Perrine L; Kamal, Brishna; Wallis, Deeann; Larivière, Roxanne; Vallée, Joanne; Robitaille, Richard; Tsuda, Hiroshi

2015-11-15

Missense mutations (P56S) in Vapb are associated with autosomal dominant motor neuron diseases: amyotrophic lateral sclerosis and lower motor neuron disease. Although transgenic mice overexpressing the mutant vesicle-associated membrane protein-associated protein B (VAPB) protein with neuron-specific promoters have provided some insight into the toxic properties of the mutant proteins, their role in pathogenesis remains unclear. To identify pathological defects in animals expressing the P56S mutant VAPB protein at physiological levels in the appropriate tissues, we have generated Vapb knock-in mice replacing wild-type Vapb gene with P56S mutant Vapb gene and analyzed the resulting pathological phenotypes. Heterozygous P56S Vapb knock-in mice show mild age-dependent defects in motor behaviors as characteristic features of the disease. The homozygous P56S Vapb knock-in mice show more severe defects compared with heterozygous mice reflecting the dominant and dose-dependent effects of P56S mutation. Significantly, the knock-in mice demonstrate accumulation of P56S VAPB protein and ubiquitinated proteins in cytoplasmic inclusions, selectively in motor neurons. The mutant mice demonstrate induction of ER stress and autophagic response in motor neurons before obvious onset of behavioral defects, suggesting that these cellular biological defects might contribute to the initiation of the disease. The P56S Vapb knock-in mice could be a valuable tool to gain a better understanding of the mechanisms by which the disease arises. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Minority stress and college persistence attitudes among African American, Asian American, and Latino students: perception of university environment as a mediator.

PubMed

Wei, Meifen; Ku, Tsun-Yao; Liao, Kelly Yu-Hsin

2011-04-01

We examined whether perception of university environment mediated the association between minority status stress and college persistence attitudes after controlling for perceived general stress. Participants were 160 Asian American, African American, and Latino students who attended a predominantly White university. Results of a path model analysis showed that university environment was a significant mediator for the association between minority status stress and college persistence attitudes. Additionally, minority status stress was distinct from perceived general stress. Finally, the results from a multiple-group comparison indicated that the magnitude of the mediation effect was invariant across Asian American, African American, and Latino college students, thus supporting the generalizability of the mediation model.

Stress-Triggered Phase Separation Is an Adaptive, Evolutionarily Tuned Response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riback, Joshua A.; Katanski, Christopher D.; Kear-Scott, Jamie L.

In eukaryotic cells, diverse stresses trigger coalescence of RNA-binding proteins into stress granules. In vitro, stress-granule-associated proteins can demix to form liquids, hydrogels, and other assemblies lacking fixed stoichiometry. Observing these phenomena has generally required conditions far removed from physiological stresses. We show that poly(A)-binding protein (Pab1 in yeast), a defining marker of stress granules, phase separates and forms hydrogels in vitro upon exposure to physiological stress conditions. Other RNA-binding proteins depend upon low-complexity regions (LCRs) or RNA for phase separation, whereas Pab1’s LCR is not required for demixing, and RNA inhibits it. Based on unique evolutionary patterns, we createmore » LCR mutations, which systematically tune its biophysical properties and Pab1 phase separation in vitro and in vivo. Mutations that impede phase separation reduce organism fitness during prolonged stress. Poly(A)-binding protein thus acts as a physiological stress sensor, exploiting phase separation to precisely mark stress onset, a broadly generalizable mechanism.« less

The Influence of Perceived Stress, Loneliness, and Learning Burnout on University Students' Educational Experience

ERIC Educational Resources Information Center

Stoliker, Bryce E.; Lafreniere, Kathryn D.

2015-01-01

University is a pivotal period in a young adult's life; however, for some, university may be a recipe for disaster due to the stress and pressures that come along with university education. The purpose of the present study was to examine students' feelings of stress, loneliness, and levels of learning burnout in order to determine if these factors…

Association of Anxiety and Depression With Microtubule-Associated Protein 2– and Synaptopodin-Immunolabeled Dendrite and Spine Densities in Hippocampal CA3 of Older Humans

PubMed Central

Soetanto, Ainie; Wilson, Robert S.; Talbot, Konrad; Un, Ashley; Schneider, Julie A.; Sobiesk, Mark; Kelly, Jeremiah; Leurgans, Sue; Bennett, David A.; Arnold, Steven E.

2010-01-01

Context Chronic psychological distress has deleterious effects on many of the body’s physiological systems. In experimental animal models, chronic stress leads to neuroanatomic changes in the hippocampus, in particular a decrease in the length and branching of dendrites as well as a decrease in the number of dendritic spines. Objectives To examine whether analogous distress-related neuroanatomic changes occur in humans and whether such changes might also be related to cognitive dysfunction observed in older people who report greater psychological distress. Design Postmortem study of brain tissues from participants of the Religious Orders Study, an ongoing population-based clinicopathological study of aging and cognition. Setting The Rush University Religious Orders Study and the University of Pennsylvania Cellular and Molecular Neuropathology Program. Participants Seventy-two deceased participants of the Religious Orders Study. Main Outcome Measures Densities of microtubule-associated protein 2–immunolabeled dendrites and synaptopodin-immunolabeled dendritic spines in the CA3 subfield of the hippocampus, quantified using semiautomated image acquisition and analysis. Results Higher levels of trait anxiety and longitudinal depression scores were associated with decreased densities of dendrites and spines in CA3. Dendrite and spine densities did not correlate with an index of global cognition or with densities of common age-related pathological changes. Conclusions Regressive neuronal changes occur in humans who experience greater psychological distress. These changes are analogous to neuronal changes in animal models of chronic stress. PMID:20439826

Differential expression profiles of poplar MAP kinase kinases in response to abiotic stresses and plant hormones, and overexpression of PtMKK4 improves the drought tolerance of poplar.

PubMed

Wang, Lei; Su, Hongyan; Han, Liya; Wang, Chuanqi; Sun, Yanlin; Liu, Fenghong

2014-07-15

Mitogen-activated protein kinase (MAPK) cascades are universal signal transduction modules that play essential roles in plant growth, development and stress response. MAPK kinases (MAPKKs), which link MAPKs and MAPKK kinases (MAPKKKs), are integral in mediating various stress responses in plants. However, to date few data about the roles of poplar MAPKKs in stress signal transduction are available. In this study, we performed a systemic analysis of poplar MAPKK gene family expression profiles in response to several abiotic stresses and stress-associated hormones. Furthermore, Populus trichocarpa MAPKK4 (PtMKK4) was chosen for functional characterization. Transgenic analysis showed that overexpression of the PtMKK4 gene remarkably enhanced drought stress tolerance in the transgenic poplar plants. The PtMKK4-overexpressing plants also exhibited much lower levels of H2O2 and higher antioxidant enzyme activity after exposure to drought stress compared to the wide type lines. Besides, some drought marker genes including PtP5CS, PtSUS3, PtLTP3 and PtDREB8 exhibited higher expression levels in the transgenic lines than in the wide type under drought conditions. This study provided valuable information for understanding the putative functions of poplar MAPKKs involved in important signaling pathways under different stress conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Recovery from heat, salt and osmotic stress in Physcomitrella patens requires a functional small heat shock protein PpHsp16.4

PubMed Central

2013-01-01

Background Plant small heat shock proteins (sHsps) accumulate in response to various environmental stresses, including heat, drought, salt and oxidative stress. Numerous studies suggest a role for these proteins in stress tolerance by preventing stress-induced protein aggregation as well as by facilitating protein refolding by other chaperones. However, in vivo evidence for the involvement of sHsps in tolerance to different stress factors is still missing, mainly due to the lack of appropriate mutants in specific sHsp genes. Results In this study we characterized the function of a sHsp in abiotic stress tolerance in the moss Physcomitrella patens, a model for primitive land plants. Using suppression subtractive hybridization, we isolated an abscisic acid-upregulated gene from P. patens encoding a 16.4 kDa cytosolic class II sHsp. PpHsp16.4 was also induced by salicylic acid, dithiothreitol (DTT) and by exposure to various stimuli, including osmotic and salt stress, but not by oxidative stress-inducing compounds. Expression of the gene was maintained upon stress relief, suggesting a role for this protein in the recovery stage. PpHsp16.4 is encoded by two identical genes arranged in tandem in the genome. Targeted disruption of both genes resulted in the inability of plants to recover from heat, salt and osmotic stress. In vivo localization studies revealed that PpHsp16.4 localized in cytosolic granules in the vicinity of chloroplasts under non stress conditions, suggesting possible distinct roles for this protein under stress and optimal growth. Conclusions We identified a member of the class II sHsp family that showed hormonal and abiotic stress gene regulation. Induction of the gene by DTT treatment suggests that damaged proteins may act as signals for the stress-induction of PpHsp16.4. The product of this gene was shown to localize in cytosolic granules near the chloroplasts, suggesting a role for the protein in association with these organelles. Our study provides the first direct genetic evidence for a role of a sHsp in osmotic and salt stress tolerance, and supports a function for this protein particularly during the stress recovery stage of P. patens. PMID:24188413

Recovery from heat, salt and osmotic stress in Physcomitrella patens requires a functional small heat shock protein PpHsp16.4.

PubMed

Ruibal, Cecilia; Castro, Alexandra; Carballo, Valentina; Szabados, László; Vidal, Sabina

2013-11-05

Plant small heat shock proteins (sHsps) accumulate in response to various environmental stresses, including heat, drought, salt and oxidative stress. Numerous studies suggest a role for these proteins in stress tolerance by preventing stress-induced protein aggregation as well as by facilitating protein refolding by other chaperones. However, in vivo evidence for the involvement of sHsps in tolerance to different stress factors is still missing, mainly due to the lack of appropriate mutants in specific sHsp genes. In this study we characterized the function of a sHsp in abiotic stress tolerance in the moss Physcomitrella patens, a model for primitive land plants. Using suppression subtractive hybridization, we isolated an abscisic acid-upregulated gene from P. patens encoding a 16.4 kDa cytosolic class II sHsp. PpHsp16.4 was also induced by salicylic acid, dithiothreitol (DTT) and by exposure to various stimuli, including osmotic and salt stress, but not by oxidative stress-inducing compounds. Expression of the gene was maintained upon stress relief, suggesting a role for this protein in the recovery stage. PpHsp16.4 is encoded by two identical genes arranged in tandem in the genome. Targeted disruption of both genes resulted in the inability of plants to recover from heat, salt and osmotic stress. In vivo localization studies revealed that PpHsp16.4 localized in cytosolic granules in the vicinity of chloroplasts under non stress conditions, suggesting possible distinct roles for this protein under stress and optimal growth. We identified a member of the class II sHsp family that showed hormonal and abiotic stress gene regulation. Induction of the gene by DTT treatment suggests that damaged proteins may act as signals for the stress-induction of PpHsp16.4. The product of this gene was shown to localize in cytosolic granules near the chloroplasts, suggesting a role for the protein in association with these organelles. Our study provides the first direct genetic evidence for a role of a sHsp in osmotic and salt stress tolerance, and supports a function for this protein particularly during the stress recovery stage of P. patens.

[Evaluation of the treatment with D-chiro-inositol on levels of oxidative stress in PCOS patients].

PubMed

De Leo, V; La Marca, A; Cappelli, V; Stendardi, A; Focarelli, R; Musacchio, M C; Piomboni, P

2012-12-01

Recent studies on the pathophysiology of infertility have shown that oxidative stress (OS) can be one of the causal factors. The OS is, by definition, an imbalance between the production of reactive oxygen species (ROS) and antioxidant defense systems. It seems that oxidative stress plays an important role in almost all phases of human reproduction. In fact, ROS are involved in the modulation of a large spectrum of reproductive functions such as oocyte maturation, ovarian steroidogenesis, corpus luteum functions and are involved in the processes of fertilization, embryo development and pregnancy, but also in some diseases that cause infertility. Polycystic ovary syndrome (PCOS) has recently been associated with increased oxidative stress, often put in relation to the syndrome's typical metabolic disorder. Inositol is an intracellular mediator of insulin, currently much used as a therapeutic agent in PCOS. While its main action takes place via insulin sensitization, little is known about the possible effects of other disorders, such as oxidative stress, associated with PCOS. The purpose of this study was therefore to assess the effect of D-chiro-inositol on the state of oxidative stress in the follicular fluid of women with PCOS. Follicular fluids were obtained from women who have turned to the Center for Diagnosis and Treatment of Sterility of Obstetrics and Gynecology of the University Hospital of Siena and Modena diagnosed with PCOS. The women were treated with D-chiro-inositol (500 mg x 2 per day) for 3 months before being subjected to cycles of in vitro fertilization (IVF). The state of oxidative stress was measured by marking of free thiol groups of proteins in the follicular fluid with 3-(N-Maleimidopropionyl)-biocytin. In our study we obtained a lesser presence of free thiol protein groups equal to 77.8% in the follicular fluid of women with PCOS not treated with D-chiro-inositolo, compared to patients who instead have carried out such treatment. These results suggest that in PCOS women there is an increase of the oxidation of thiol groups of proteins follicular, correlated to a progressive increase of the oxidative stress and that the administration of D-chiro-inositol in patients with this disease seems to reduce the oxidation of thiol groups.

Aerobic kinetoplastid flagellate Phytomonas does not require heme for viability

PubMed Central

Kořený, Luděk; Sobotka, Roman; Kovářová, Julie; Gnipová, Anna; Flegontov, Pavel; Horváth, Anton; Oborník, Miroslav; Ayala, Francisco J.; Lukeš, Julius

2012-01-01

Heme is an iron-coordinated porphyrin that is universally essential as a protein cofactor for fundamental cellular processes, such as electron transport in the respiratory chain, oxidative stress response, or redox reactions in various metabolic pathways. Parasitic kinetoplastid flagellates represent a rare example of organisms that depend on oxidative metabolism but are heme auxotrophs. Here, we show that heme is fully dispensable for the survival of Phytomonas serpens, a plant parasite. Seeking to understand the metabolism of this heme-free eukaryote, we searched for heme-containing proteins in its de novo sequenced genome and examined several cellular processes for which heme has so far been considered indispensable. We found that P. serpens lacks most of the known hemoproteins and does not require heme for electron transport in the respiratory chain, protection against oxidative stress, or desaturation of fatty acids. Although heme is still required for the synthesis of ergosterol, its precursor, lanosterol, is instead incorporated into the membranes of P. serpens grown in the absence of heme. In conclusion, P. serpens is a flagellate with unique metabolic adaptations that allow it to bypass all requirements for heme. PMID:22355128

Aerobic kinetoplastid flagellate Phytomonas does not require heme for viability.

PubMed

Kořený, Luděk; Sobotka, Roman; Kovářová, Julie; Gnipová, Anna; Flegontov, Pavel; Horváth, Anton; Oborník, Miroslav; Ayala, Francisco J; Lukeš, Julius

2012-03-06

Heme is an iron-coordinated porphyrin that is universally essential as a protein cofactor for fundamental cellular processes, such as electron transport in the respiratory chain, oxidative stress response, or redox reactions in various metabolic pathways. Parasitic kinetoplastid flagellates represent a rare example of organisms that depend on oxidative metabolism but are heme auxotrophs. Here, we show that heme is fully dispensable for the survival of Phytomonas serpens, a plant parasite. Seeking to understand the metabolism of this heme-free eukaryote, we searched for heme-containing proteins in its de novo sequenced genome and examined several cellular processes for which heme has so far been considered indispensable. We found that P. serpens lacks most of the known hemoproteins and does not require heme for electron transport in the respiratory chain, protection against oxidative stress, or desaturation of fatty acids. Although heme is still required for the synthesis of ergosterol, its precursor, lanosterol, is instead incorporated into the membranes of P. serpens grown in the absence of heme. In conclusion, P. serpens is a flagellate with unique metabolic adaptations that allow it to bypass all requirements for heme.

A Causal Relationship of Occupational Stress among University Employees

PubMed Central

KAEWANUCHIT, Chonticha; MUNTANER, Carles; ISHA, Nizam

2015-01-01

Background: Occupational stress is a psychosocial dimension of occupational health concept on social determinants of health, especially, job & environmental condition. Recently, staff network of different government universities of Thailand have called higher education commission, and Ministry of Education, Thailand to resolve the issue of government education policy (e.g. wage inequity, poor welfare, law, and job & environment condition) that leads to their job insecurity, physical and mental health problems from occupational stress. The aim of this study was to investigate a causal relationship of occupational stress among the academic university employees. Methods: This cross sectional research was conducted in 2014 among 2,000 academic university employees at Thai government universities using stratified random sampling. Independent variables were wage, family support, periods of duty, and job & environmental condition. Dependent variable was stress. Results: Job & environmental condition, as social and environmental factor, and periods of duty as individual factor had direct effect to stress (P< 0.05). Family support, as family factor, and wage, as individual factor had direct effect to stress (P < 0.05). Both family support and wage were the causal endogenous variables. Conclusion: Job & environmental condition and periods of duty were increased so that it associated with occupational stress among academic university employees at moderate level. PMID:26576371

Hypertonic stress induces rapid and widespread protein damage in C. elegans

PubMed Central

Burkewitz, Kris; Choe, Keith

2011-01-01

Proteostasis is defined as the homeostatic mechanisms that maintain the function of all cytoplasmic proteins. We recently demonstrated that the capacity of the proteostasis network is a critical factor that defines the limits of cellular and organismal survival in hypertonic environments. The current studies were performed to determine the extent of protein damage induced by cellular water loss. Using worm strains expressing fluorescently tagged foreign and endogenous proteins and proteins with temperature-sensitive point mutations, we demonstrate that hypertonic stress causes aggregation and misfolding of diverse proteins in multiple cell types. Protein damage is rapid. Aggregation of a polyglutamine yellow fluorescent protein reporter is observable with <1 h of hypertonic stress, and aggregate volume doubles approximately every 10 min. Aggregate formation is irreversible and occurs after as little as 10 min of exposure to hypertonic conditions. To determine whether endogenous proteins are aggregated by hypertonic stress, we quantified the relative amount of total cellular protein present in detergent-insoluble extracts. Exposure for 4 h to 400 mM or 500 mM NaCl induced a 55–120% increase in endogenous protein aggregation. Inhibition of insulin signaling or acclimation to mild hypertonic stress increased survival under extreme hypertonic conditions and prevented aggregation of endogenous proteins. Our results demonstrate that hypertonic stress causes widespread and dramatic protein damage and that cells have a significant capacity to remodel the network of proteins that function to maintain proteostasis. These findings have important implications for understanding how cells cope with hypertonic stress and other protein-damaging stressors. PMID:21613604

Diet-induced obesity associated with steatosis, oxidative stress, and inflammation in liver.

PubMed

Peng, Yanhua; Rideout, Drew; Rakita, Steven; Lee, James; Murr, Michel

2012-01-01

Obesity induces steatosis and increases oxidative stress, as well as chronic inflammation in the liver. The balance between lipogenesis and lipolysis is disrupted in obese animals. At a cellular level, the changes in metabolic sensors and energy regulators are poorly understood. We hypothesized that diet-induced steatosis increases oxidative stress, inflammation, and changes the metabolic regulators to promote energy storage in mice. The setting was a university-affiliated basic science research laboratory. Four-week-old C57BL mice were fed a high-fat diet (n = 8) or regular chow (n = 8) for 7 weeks. The liver sections were stained for fat content and immunofluorescence. Liver homogenates were used for protein analysis by immunoblotting and mRNA analysis by reverse transcriptase-polymerase chain reaction. The gels were quantified using densitometry P ≤ .05 was considered significant. The high-fat diet upregulated protein kinase-C atypical isoforms ζ and λ and decreased glucose tolerance and the interaction of insulin receptor substrate 2 with phosphoinositide kinase-3. The high-fat diet increased the transcriptional factors liver X receptor (4321 ± 98 versus 2981 ± 80) and carbohydrate response element-binding protein (5132 ± 135 versus 3076 ± 91), the lipogenesis genes fatty acid binding protein 5, stearoyl-co-enzyme A desaturase-1, and acetyl-co-enzyme A carboxylase protein, and fatty acid synthesis. The high-fat diet decreased 5'-adenosine monophosphate-activated protein kinase (2561 ± 78 versus 1765 ± 65), glucokinase-3β (2.214 ± 34 versus 3356 ± 86), and SIRT1 (2015 ± 76 versus 3567 ± 104) and increased tumor necrosis factor-α (3415 ± 112 versus 2042 ± 65), nuclear factor kappa B (5123 ± 201 versus 2562 ± 103), cyclooxygenase-2 (4230 ± 113 versus 2473 ± 98), nicotinamide-adenine dinucleotide phosphate oxidase (3501 ± 106 versus 1600 ± 69) and reactive oxygen species production (all P < .001, obese mice versus lean mice). A high-fat diet impairs glucose tolerance and hepatic insulin signaling, upregulates transcriptional and translational activities that promote lipogenesis, cytokine production, proinflammatory signaling, and oxidative stress, and downregulates lipolysis. Understanding the complex cellular signals triggered by obesity might have profound clinical implications. Published by Elsevier Inc.

Differential proteomic analysis of grapevine leaves by iTRAQ reveals responses to heat stress and subsequent recovery

PubMed Central

2014-01-01

Background High temperature is a major environmental factor limiting grape yield and affecting berry quality. Thermotolerance includes the direct response to heat stress and the ability to recover from heat stress. To better understand the mechanism of the thermotolerance of Vitis, we combined a physiological analysis with iTRAQ-based proteomics of Vitis vinifera cv Cabernet Sauvignon, subjected to 43°C for 6 h, and then followed by recovery at 25/18°C. Results High temperature increased the concentrations of TBARS and inhibited electronic transport in photosynthesis apparatus, indicating that grape leaves were damaged by heat stress. However, these physiological changes rapidly returned to control levels during the subsequent recovery phase from heat stress. One hundred and seventy-four proteins were differentially expressed under heat stress and/or during the recovery phase, in comparison to unstressed controls, respectively. Stress and recovery conditions shared 42 proteins, while 113 and 103 proteins were respectively identified under heat stress and recovery conditions alone. Based on MapMan ontology, functional categories for these dysregulated proteins included mainly photosynthesis (about 20%), proteins (13%), and stress (8%). The subcellular localization using TargetP showed most proteins were located in the chloroplasts (34%), secretory pathways (8%) and mitochondrion (3%). Conclusion On the basis of these findings, we proposed that some proteins related to electron transport chain of photosynthesis, antioxidant enzymes, HSPs and other stress response proteins, and glycolysis may play key roles in enhancing grapevine adaptation to and recovery capacity from heat stress. These results provide a better understanding of the proteins involved in, and mechanisms of thermotolerance in grapevines. PMID:24774513

Taxonomic distribution and origins of the extended LHC (light-harvesting complex) antenna protein superfamily

PubMed Central

2010-01-01

Background The extended light-harvesting complex (LHC) protein superfamily is a centerpiece of eukaryotic photosynthesis, comprising the LHC family and several families involved in photoprotection, like the LHC-like and the photosystem II subunit S (PSBS). The evolution of this complex superfamily has long remained elusive, partially due to previously missing families. Results In this study we present a meticulous search for LHC-like sequences in public genome and expressed sequence tag databases covering twelve representative photosynthetic eukaryotes from the three primary lineages of plants (Plantae): glaucophytes, red algae and green plants (Viridiplantae). By introducing a coherent classification of the different protein families based on both, hidden Markov model analyses and structural predictions, numerous new LHC-like sequences were identified and several new families were described, including the red lineage chlorophyll a/b-binding-like protein (RedCAP) family from red algae and diatoms. The test of alternative topologies of sequences of the highly conserved chlorophyll-binding core structure of LHC and PSBS proteins significantly supports the independent origins of LHC and PSBS families via two unrelated internal gene duplication events. This result was confirmed by the application of cluster likelihood mapping. Conclusions The independent evolution of LHC and PSBS families is supported by strong phylogenetic evidence. In addition, a possible origin of LHC and PSBS families from different homologous members of the stress-enhanced protein subfamily, a diverse and anciently paralogous group of two-helix proteins, seems likely. The new hypothesis for the evolution of the extended LHC protein superfamily proposed here is in agreement with the character evolution analysis that incorporates the distribution of families and subfamilies across taxonomic lineages. Intriguingly, stress-enhanced proteins, which are universally found in the genomes of green plants, red algae, glaucophytes and in diatoms with complex plastids, could represent an important and previously missing link in the evolution of the extended LHC protein superfamily. PMID:20673336

Paraoxonase: The Universal Factor of Antioxidant Defense in Human Body.

PubMed

Borovkova, E I; Antipova, N V; Komeenko, T V; Shakhparonov, M I; Borovkov, I M

The paraoxonase (PON) gene family includes three members: PON1, PON2, and PON3 aligned in tandem on chromosome 7 in humans. All PON proteins share considerable structural homology and have the capacity to protect cells from oxidative stress; therefore, they have been implicated in the pathogenesis of several inflammatory diseases, particularly atherosclerosis. Increased production of reactive oxygen species as a result of decreased activities of mitochondrial electron transport chain complexes plays a role in the development of many inflammatory diseases, including atherosclerosis. PON1 and PON3 proteins can be detected in plasma and reside in the high-density lipoprotein fraction and protect against oxidative stress by hydrolyzing certain oxidized lipids in lipoproteins, macrophages, and atherosclerotic lesions. Paraoxonase 2 (PON2) possesses antiatherogenic properties and is associated with lower ROS levels. PON2 is involved in the antioxidative and anti-inflammatory response in intestinal epithelial cells. In contrast to PON1 and PON3, PON2 is cell-associated and is not found in plasma. It is widely expressed in a variety of tissues, including the kidney, and protects against cellular oxidative stress. Overexpression of PON2 reduces oxidative status, prevents apoptosis in vascular endothelial cells, and inhibits cell-mediated low density lipoprotein oxidation. PON2 also inhibits the development of atherosclerosis, via mechanisms involving the reduction of oxidative stress. In this review we explore the physiological roles of PON in disease development and modulation of PONs by infective (bacterial, viral) agents.

Elongator-dependent modification of cytoplasmic tRNALysUUU is required for mitochondrial function under stress conditions.

PubMed

Tigano, Marco; Ruotolo, Roberta; Dallabona, Cristina; Fontanesi, Flavia; Barrientos, Antoni; Donnini, Claudia; Ottonello, Simone

2015-09-30

To gain a wider view of the pathways that regulate mitochondrial function, we combined the effect of heat stress on respiratory capacity with the discovery potential of a genome-wide screen in Saccharomyces cerevisiae. We identified 105 new genes whose deletion impairs respiratory growth at 37°C by interfering with processes such as transcriptional regulation, ubiquitination and cytosolic tRNA wobble uridine modification via 5-methoxycarbonylmethyl-2-thiouridine formation. The latter process, specifically required for efficient decoding of AA-ending codons under stress conditions, was covered by multiple genes belonging to the Elongator (e.g. ELP3) and urmylation (e.g., NCS6) pathways. ELP3 or NCS6 deletants had impaired mitochondrial protein synthesis. Their respiratory deficiency was selectively rescued by overexpression of tRNA(Lys) UUU as well by overexpression of genes (BCK1 and HFM1) with a strong bias for the AAA codon read by this tRNA. These data extend the mitochondrial regulome, demonstrate that heat stress can impair respiration by disturbing cytoplasmic translation of proteins critically involved in mitochondrial function and document, for the first time, the involvement in such process of the Elongator and urmylation pathways. Given the conservation of these pathways, the present findings may pave the way to a better understanding of the human mitochondrial regulome in health and disease. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Identification of Proteins Using iTRAQ and Virus-Induced Gene Silencing Reveals Three Bread Wheat Proteins Involved in the Response to Combined Osmotic-Cold Stress.

PubMed

Zhang, Ning; Zhang, Lingran; Shi, Chaonan; Zhao, Lei; Cui, Dangqun; Chen, Feng

2018-05-25

Crops are often subjected to a combination of stresses in the field. To date, studies on the physiological and molecular responses of common wheat to a combination of osmotic and cold stresses, however, remain unknown. In this study, wheat seedlings exposed to osmotic-cold stress for 24 h showed inhibited growth, as well as increased lipid peroxidation, relative electrolyte leakage, and soluble sugar contents. iTRAQ-based quantitative proteome method was employed to determine the proteomic profiles of the roots and leaves of wheat seedlings exposed to osmotic-cold stress conditions. A total of 250 and 258 proteins with significantly altered abundance in the roots and leaves were identified, respectively, and the majority of these proteins displayed differential abundance, thereby revealing organ-specific differences in adaptation to osmotic-cold stress. Yeast two hybrid assay examined five pairs of stress/defense-related protein-protein interactions in the predicted protein interaction network. Furthermore, quantitative real-time PCR analysis indicated that abiotic stresses increased the expression of three candidate protein genes, i.e., TaGRP2, CDCP, and Wcor410c in wheat leaves. Virus-induced gene silencing indicated that three genes TaGRP2, CDCP, and Wcor410c were involved in modulating osmotic-cold stress in common wheat. Our study provides useful information for the elucidation of molecular and genetics bases of osmotic-cold combined stress in bread wheat.

The stress response system of proteins: Implications for bioreactor scaleup

NASA Technical Reports Server (NTRS)

Goochee, Charles F.

1988-01-01

Animal cells face a variety of environmental stresses in large scale bioreactors, including periodic variations in shear stress and dissolved oxygen concentration. Diagnostic techniques were developed for identifying the particular sources of environmental stresses for animal cells in a given bioreactor configuration. The mechanisms by which cells cope with such stresses was examined. The individual concentrations and synthesis rates of hundreds of intracellular proteins are affected by the extracellular environment (medium composition, dissolved oxygen concentration, ph, and level of surface shear stress). Techniques are currently being developed for quantifying the synthesis rates and concentrations of the intracellular proteins which are most sensitive to environmental stress. Previous research has demonstrated that a particular set of stress response proteins are synthesized by mammalian cells in response to temperature fluctuations, dissolved oxygen deprivation, and glucose deprivation. Recently, it was demonstrated that exposure of human kidney cells to high shear stress results in expression of a completely distinct set of intracellular proteins.

A comparative proteomic analysis of Bacillus coagulans in response to lactate stress during the production of L-lactic acid.

PubMed

Wang, Xiuwen; Qin, Jiayang; Wang, Landong; Xu, Ping

2014-12-01

The growth rate and maximum biomass of Bacillus coagulans 2-6 were inhibited by lactate; inhibition by sodium lactate was stronger than by calcium lactate. The differences of protein expressions by B. coagulans 2-6 under the lactate stress were determined using two-dimensional electrophoresis coupled with mass spectrometric identification. Under the non-stress condition, calcium lactate stress and sodium lactate stress, the number of detected protein spots was 1,571 ± 117, 1,281 ± 231 and 904 ± 127, respectively. Four proteins with high expression under lactate stress were identified: lactate dehydrogenase, cysteine synthase A, aldo/keto reductase and ribosomal protein L7/L12. These proteins are thus potential targets for the reconstruction of B. coagulans to promote its resistance to lactate stress.

The Relationship between Occupational Stress and Job Satisfaction: The Case of Pakistani Universities

ERIC Educational Resources Information Center

Chaudhry, Abdul Qayyum

2012-01-01

This paper aims to find out the relationship between occupational stress and job satisfaction based on age, gender, nature of job, cadre, work experience of university teachers, and sector of university. The Pearson correlation indicates: no significant relationship found between job satisfaction and overall occupational stress; inverse…

Active tuberculosis patients have high levels of IgA anti-alpha-crystallin and isocitrate lyase proteins.

PubMed

Talavera-Paulín, M; García-Morales, L; Ruíz-Sánchez, B P; Caamal-Ley, Á D; Hernández-Solis, A; Ramírez-Casanova, E; Cicero-Sabido, R; Espitia, C; Helguera-Repetto, C; González-Y-Merchand, J A; Flores-Mejía, R; Estrada-Parra, S; Estrada-García, I; Chacón-Salinas, R; Wong-Baeza, I; Serafín-López, J

2016-12-01

Mexico City, Mexico. To identify proteins synthetised by Mycobacterium tuberculosis in hypoxic culture, which resemble more closely a granuloma environment than aerobic culture, and to determine if they are recognised by antibodies from patients with active pulmonary tuberculosis (PTB). Soluble extracts from M. tuberculosis H37Rv cultured under aerobic or hypoxic conditions were analysed using two-dimensional polyacrylamide gel electrophoresis, and proteins over-expressed under hypoxia were identified by mass spectrometry. The presence of immunoglobulin (Ig) G, IgA and IgM antibodies against these proteins was determined in the serum of 42 patients with active PTB and 42 healthy controls. We selected three M. tuberculosis H37Rv proteins (alpha-crystallin protein [Acr, Rv2031c], universal stress protein Rv2623 and isocitrate lyase [ICL, RV0467]) that were over-expressed under hypoxia. Titres of anti-Acr and anti-ICL IgA antibodies were higher in patients than in healthy controls, with an area under the receiver operating characteristic curve of 0.71 for anti-ICL IgA antibodies. ICL could be used in combination with other M. tuberculosis antigens to improve the sensitivity and specificity of current serological TB diagnostic methods.

Changes of testicular phosphorylated proteins in response to restraint stress in male rats*

PubMed Central

Arun, Supatcharee; Burawat, Jaturon; Sukhorum, Wannisa; Sampannang, Apichakan; Uabundit, Nongnut; Iamsaard, Sitthichai

2016-01-01

Objective: To investigate male reproductive parameters via changes of potential testicular protein markers in restraint-stress rats. Methods: Male Sprague-Dawley rats were divided into two groups (non-immobilized control and restraint-immobilized/stress groups, n=8 each group). The stress animals were immobilized (12 h/d) by a restraint cage for 7 consecutive days. All reproductive parameters, morphology and histology were observed and compared between groups. In addition, the expression of steroidogenic acute regulatory (StAR) and phosphotyrosine proteins (previously localized in Sertoli and late spermatid cells) in testicular lysate was assayed by immuno-Western blotting. Results: Testosterone level, sperm concentration and sperm head normality of stress rats were significantly decreased while the corticosterone level was increased as compared with the control (P<0.05). Histologically, stress rats showed low sperm mass in epididymal lumen and some atrophy of seminiferous tubules. Although the expression of testicular StAR protein was not significantly different between groups, changed patterns of the 131, 95, and 75 kDa testicular phosphorylated proteins were observed in the stress group compared with the control group. The intensity of a testicular 95-kDa phosphorylated protein was significantly decreased in stress rats. Conclusions: This study has demonstrated the alteration of testicular phosphorylated protein patterns, associated with adverse male reproductive parameters in stress rats. It could be an explanation of some infertility in stress males. PMID:26739523

In-silico identification and characterization of organic and inorganic chemical stress responding genes in yeast (Saccharomyces cerevisiae).

PubMed

Barozai, Muhammad Younas Khan; Bashir, Farrukh; Muzaffar, Shafia; Afzal, Saba; Behlil, Farida; Khan, Muzaffar

2014-10-15

To study the life processes of all eukaryotes, yeast (Saccharomyces cerevisiae) is a significant model organism. It is also one of the best models to study the responses of genes at transcriptional level. In a living organism, gene expression is changed by chemical stresses. The genes that give response to chemical stresses will provide good source for the strategies in engineering and formulating mechanisms which are chemical stress resistant in the eukaryotic organisms. The data available through microarray under the chemical stresses like lithium chloride, lactic acid, weak organic acids and tomatidine were studied by using computational tools. Out of 9335 yeast genes, 388 chemical stress responding genes were identified and characterized under different chemical stresses. Some of these are: Enolases 1 and 2, heat shock protein-82, Yeast Elongation Factor 3, Beta Glucanase Protein, Histone H2A1 and Histone H2A2 Proteins, Benign Prostatic Hyperplasia, ras GTPase activating protein, Establishes Silent Chromatin protein, Mei5 Protein, Nondisjunction Protein and Specific Mitogen Activated Protein Kinase. Characterization of these genes was also made on the basis of their molecular functions, biological processes and cellular components. Copyright © 2014 Elsevier B.V. All rights reserved.

Hypothesis: NDL proteins function in stress responses by regulating microtubule organization

PubMed Central

Khatri, Nisha; Mudgil, Yashwanti

2015-01-01

N-MYC DOWNREGULATED-LIKE proteins (NDL), members of the alpha/beta hydrolase superfamily were recently rediscovered as interactors of G-protein signaling in Arabidopsis thaliana. Although the precise molecular function of NDL proteins is still elusive, in animals these proteins play protective role in hypoxia and expression is induced by hypoxia and nickel, indicating role in stress. Homology of NDL1 with animal counterpart N-MYC DOWNREGULATED GENE (NDRG) suggests similar functions in animals and plants. It is well established that stress responses leads to the microtubule depolymerization and reorganization which is crucial for stress tolerance. NDRG is a microtubule-associated protein which mediates the microtubule organization in animals by causing acetylation and increases the stability of α-tubulin. As NDL1 is highly homologous to NDRG, involvement of NDL1 in the microtubule organization during plant stress can also be expected. Discovery of interaction of NDL with protein kinesin light chain- related 1, enodomembrane family protein 70, syntaxin-23, tubulin alpha-2 chain, as a part of G protein interactome initiative encourages us to postulate microtubule stabilizing functions for NDL family in plants. Our search for NDL interactors in G protein interactome also predicts the role of NDL proteins in abiotic stress tolerance management. Based on published report in animals and predicted interacting partners for NDL in G protein interactome lead us to hypothesize involvement of NDL in the microtubule organization during abiotic stress management in plants. PMID:26583023

Hypothesis: NDL proteins function in stress responses by regulating microtubule organization.

PubMed

Khatri, Nisha; Mudgil, Yashwanti

2015-01-01

N-MYC DOWNREGULATED-LIKE proteins (NDL), members of the alpha/beta hydrolase superfamily were recently rediscovered as interactors of G-protein signaling in Arabidopsis thaliana. Although the precise molecular function of NDL proteins is still elusive, in animals these proteins play protective role in hypoxia and expression is induced by hypoxia and nickel, indicating role in stress. Homology of NDL1 with animal counterpart N-MYC DOWNREGULATED GENE (NDRG) suggests similar functions in animals and plants. It is well established that stress responses leads to the microtubule depolymerization and reorganization which is crucial for stress tolerance. NDRG is a microtubule-associated protein which mediates the microtubule organization in animals by causing acetylation and increases the stability of α-tubulin. As NDL1 is highly homologous to NDRG, involvement of NDL1 in the microtubule organization during plant stress can also be expected. Discovery of interaction of NDL with protein kinesin light chain- related 1, enodomembrane family protein 70, syntaxin-23, tubulin alpha-2 chain, as a part of G protein interactome initiative encourages us to postulate microtubule stabilizing functions for NDL family in plants. Our search for NDL interactors in G protein interactome also predicts the role of NDL proteins in abiotic stress tolerance management. Based on published report in animals and predicted interacting partners for NDL in G protein interactome lead us to hypothesize involvement of NDL in the microtubule organization during abiotic stress management in plants.

Organ-specific proteomics analysis for identification of response mechanism in soybean seedlings under flooding stress.

PubMed

Khatoon, Amana; Rehman, Shafiq; Hiraga, Susumu; Makino, Takahiro; Komatsu, Setsuko

2012-10-22

Flooding is one of the severe environmental factors which impair growth and yield in soybean plant. To investigate the organ specific response mechanism of soybean under flooding stress, changes in protein species were analyzed using a proteomics approach. Two-day-old soybeans were subjected to flooding for 5 days. Proteins were extracted from root, hypocotyl and leaf, and separated by two-dimensional polyacrylamide gel electrophoresis. In root, hypocotyl and leaf, 51, 66 and 51 protein species were significantly changed, respectively, under flooding stress. In root, metabolism related proteins were increased; however these proteins were decreased in hypocotyl and leaf. In all 3 organs, cytoplasm localized proteins were decreased, and leaf chloroplastic proteins were also decreased. Isoflavone reductase was commonly decreased at protein level in all 3 organs; however, mRNA of isoflavone reductase gene was up-regulated in leaf under flooding stress. Biophoton emission was increased in all 3 organs under flooding stress. The up-regulation of isoflavone reductase gene at transcript level; while decreased abundance at protein level indicated that flooding stress affected the mRNA translation to proteins. These results suggest that concurrence in expression of isoflavone reductase gene at mRNA and protein level along with imbalance in other disease/defense and metabolism related proteins might lead to impaired growth of root, hypocotyl and leaf of soybean seedlings under flooding stress. Copyright © 2012 Elsevier B.V. All rights reserved.

Thioredoxin-interacting protein regulates protein disulfide isomerases and endoplasmic reticulum stress.

PubMed

Lee, Samuel; Min Kim, Soo; Dotimas, James; Li, Letitia; Feener, Edward P; Baldus, Stephan; Myers, Ronald B; Chutkow, William A; Patwari, Parth; Yoshioka, Jun; Lee, Richard T

2014-06-01

The endoplasmic reticulum (ER) is responsible for protein folding, modification, and trafficking. Accumulation of unfolded or misfolded proteins represents the condition of ER stress and triggers the unfolded protein response (UPR), a key mechanism linking supply of excess nutrients to insulin resistance and type 2 diabetes in obesity. The ER harbors proteins that participate in protein folding including protein disulfide isomerases (PDIs). Changes in PDI activity are associated with protein misfolding and ER stress. Here, we show that thioredoxin-interacting protein (Txnip), a member of the arrestin protein superfamily and one of the most strongly induced proteins in diabetic patients, regulates PDI activity and UPR signaling. We found that Txnip binds to PDIs and increases their enzymatic activity. Genetic deletion of Txnip in cells and mice led to increased protein ubiquitination and splicing of the UPR regulated transcription factor X-box-binding protein 1 (Xbp1s) at baseline as well as under ER stress. Our results reveal Txnip as a novel direct regulator of PDI activity and a feedback mechanism of UPR signaling to decrease ER stress. © 2014 Brigham and Women's Hospital. Published under the terms of the CC BY 4.0 license.

MALDI-TOF Mass Spectrometry Enables a Comprehensive and Fast Analysis of Dynamics and Qualities of Stress Responses of Lactobacillus paracasei subsp. paracasei F19

PubMed Central

Schott, Ann-Sophie; Behr, Jürgen; Quinn, Jennifer; Vogel, Rudi F.

2016-01-01

Lactic acid bacteria (LAB) are widely used as starter cultures in the manufacture of foods. Upon preparation, these cultures undergo various stresses resulting in losses of survival and fitness. In order to find conditions for the subsequent identification of proteomic biomarkers and their exploitation for preconditioning of strains, we subjected Lactobacillus (Lb.) paracasei subsp. paracasei TMW 1.1434 (F19) to different stress qualities (osmotic stress, oxidative stress, temperature stress, pH stress and starvation stress). We analysed the dynamics of its stress responses based on the expression of stress proteins using MALDI-TOF mass spectrometry (MS), which has so far been used for species identification. Exploiting the methodology of accumulating protein expression profiles by MALDI-TOF MS followed by the statistical evaluation with cluster analysis and discriminant analysis of principle components (DAPC), it was possible to monitor the expression of low molecular weight stress proteins, identify a specific time point when the expression of stress proteins reached its maximum, and statistically differentiate types of adaptive responses into groups. Above the specific result for F19 and its stress response, these results demonstrate the discriminatory power of MALDI-TOF MS to characterize even dynamics of stress responses of bacteria and enable a knowledge-based focus on the laborious identification of biomarkers and stress proteins. To our knowledge, the implementation of MALDI-TOF MS protein profiling for the fast and comprehensive analysis of various stress responses is new to the field of bacterial stress responses. Consequently, we generally propose MALDI-TOF MS as an easy and quick method to characterize responses of microbes to different environmental conditions, to focus efforts of more elaborate approaches on time points and dynamics of stress responses. PMID:27783652

Perception of academic stress among Health Science Preparatory Program students in two Saudi universities.

PubMed

Alsulami, Saleh; Al Omar, Zaid; Binnwejim, Mohammed S; Alhamdan, Fahad; Aldrees, Amr; Al-Bawardi, Abdulkarim; Alsohim, Meshary; Alhabeeb, Mohammed

2018-01-01

The Health Science Preparatory Program (HSPP) is a special program that aims to enhance the educational preparedness of students for participation in a health sciences career. Students spend their first university year in a combined extensive teaching program before they can be assigned to a particular health science specialty. It is thought that students enrolled in a highly competitive environment such as HSPP with a long list of potential stressors, including developmental, academic overload, language barriers and competition, are more disposed to stress and stress-related complications. This study aims to measure the level of academic stress and to determine its risk factors in students enrolled in HSPP-adapted local universities in Saudi Arabia. The study was conducted at two Saudi universities, King Saud University (KSU) and Imam Mohammad ibn Saud Islamic University (IMSU) with competition-based and non-competition-based HSPP learning models, respectively. Both universities adopt the HSPP system. The scale for assessing academic stress (SAAS) was used to assess students' perceived stress. A total of 290 students successfully completed the questionnaire (N=290), with a mean age of 18.66 years. Mean SAAS scores for KSU and IMSU students were 8.37 (SD = 4.641) and 7.97 (SD = 5.104), P =0.480, respectively. Only "satisfaction" and "associated social and health problems" have shown statistically significant correlation with university ( P =0.000 and P =0.049, respectively). This study has found mean SAAS score for two local universities with competition-based versus non-competition-based HSPP learning models. Academic stress correlation with age, gender and universities was discussed, and valuable future work guidance was recommended.

Flavonoid-rich fraction of the Monodora tenuifolia seed extract attenuates behavioural alterations and oxidative damage in forced-swim stressed rats.

PubMed

Ekeanyanwu, Raphael Chukwuma; Njoku, Obioma Uzoma

2015-03-01

The antidepressant effects of the flavonoid-rich fraction of Monodora tenuifolia seed extract were examined by assessing the extent of attenuation of behavioural alterations and oxidative damage in the rats that were stressed by forced swim test. Compared with the model control group, the altered behavioural parameters were attenuated significantly (P < 0.05) in the group treated with the flavonoid-rich fraction (100 and 200 mg·kg(-1)), comparable to the group treated with the standard drug, fluoxetine (10 mg·kg(-1)). The flavonoid-rich fraction and fluoxetine improved significantly (P < 0.05) the activities of the antioxidant enzymes such as superoxide dismutase and catalase as well as other biochemical parameters such as reduced glutathione, protein, and nitrite in the brain of the stressed rats. These results suggested that the flavonoid-rich fraction of Monodora tenuifolia seed extract exerted the antidepressant-like effects which could be useful in the management of stress induced disease. Copyright © 2015 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Effects of abiotic stress and crop management on cereal grain composition: implications for food quality and safety.

PubMed

Halford, Nigel G; Curtis, Tanya Y; Chen, Zhiwei; Huang, Jianhua

2015-03-01

The effects of abiotic stresses and crop management on cereal grain composition are reviewed, focusing on phytochemicals, vitamins, fibre, protein, free amino acids, sugars, and oils. These effects are discussed in the context of nutritional and processing quality and the potential for formation of processing contaminants, such as acrylamide, furan, hydroxymethylfurfuryl, and trans fatty acids. The implications of climate change for cereal grain quality and food safety are considered. It is concluded that the identification of specific environmental stresses that affect grain composition in ways that have implications for food quality and safety and how these stresses interact with genetic factors and will be affected by climate change needs more investigation. Plant researchers and breeders are encouraged to address the issue of processing contaminants or risk appearing out of touch with major end-users in the food industry, and not to overlook the effects of environmental stresses and crop management on crop composition, quality, and safety as they strive to increase yield. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Interplay between reactive oxygen species and hormones in the control of plant development and stress tolerance.

PubMed

Xia, Xiao-Jian; Zhou, Yan-Hong; Shi, Kai; Zhou, Jie; Foyer, Christine H; Yu, Jing-Quan

2015-05-01

As a consequence of a sessile lifestyle, plants are continuously exposed to changing environmental conditions and often life-threatening stresses caused by exposure to excessive light, extremes of temperature, limiting nutrient or water availability, and pathogen/insect attack. The flexible coordination of plant growth and development is necessary to optimize vigour and fitness in a changing environment through rapid and appropriate responses to such stresses. The concept that reactive oxygen species (ROS) are versatile signalling molecules in plants that contribute to stress acclimation is well established. This review provides an overview of our current knowledge of how ROS production and signalling are integrated with the action of auxin, brassinosteroids, gibberellins, abscisic acid, ethylene, strigolactones, salicylic acid, and jasmonic acid in the coordinate regulation of plant growth and stress tolerance. We consider the local and systemic crosstalk between ROS and hormonal signalling pathways and identify multiple points of reciprocal control, as well as providing insights into the integration nodes that involve Ca(2+)-dependent processes and mitogen-activated protein kinase phosphorylation cascades. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Tasco®, a Product of Ascophyllum nodosum, Imparts Thermal Stress Tolerance in Caenorhabditis elegans

PubMed Central

Kandasamy, Saveetha; Fan, Di; Sangha, Jatinder Singh; Khan, Wajahatullah; Evans, Franklin; Critchley, Alan T.; Prithiviraj, Balakrishnan

2011-01-01

Tasco®, a commercial product manufactured from the brown alga Ascophyllum nodosum, has been shown to impart thermal stress tolerance in animals. We investigated the physiological, biochemical and molecular bases of this induced thermal stress tolerance using the invertebrate animal model, Caenorhabiditis elegans. Tasco® water extract (TWE) at 300 μg/mL significantly enhanced thermal stress tolerance as well as extended the life span of C. elegans. The mean survival rate of the model animals under thermal stress (35 °C) treated with 300 μg/mL and 600 μg/mL TWE, respectively, was 68% and 71% higher than the control animals. However, the TWE treatments did not affect the nematode body length, fertility or the cellular localization of daf-16. On the contrary, TWE under thermal stress significantly increased the pharyngeal pumping rate in treated animals compared to the control. Treatment with TWE also showed differential protein expression profiles over control following 2D gel-electrophoresis analysis. Furthermore, TWE significantly altered the expression of at least 40 proteins under thermal stress; among these proteins 34 were up-regulated while six were down-regulated. Mass spectroscopy analysis of the proteins altered by TWE treatment revealed that these proteins were related to heat stress tolerance, energy metabolism and a muscle structure related protein. Among them heat shock proteins, superoxide dismutase, glutathione peroxidase, aldehyde dehydrogenase, saposin-like proteins 20, myosin regulatory light chain 1, cytochrome c oxidase RAS-like, GTP-binding protein RHO A, OS were significantly up-regulated, while eukaryotic translation initiation factor 5A-1 OS, 60S ribosomal protein L18 OS, peroxiredoxin protein 2 were down regulated by TWE treatment. These results were further validated by gene expression and reporter gene expression analyses. Overall results indicate that the water soluble components of Tasco® imparted thermal stress tolerance in the C. elegans by altering stress related biochemical pathways. PMID:22163185

Role of Temperature Stress on Chloroplast Biogenesis and Protein Import in Pea1[OA

PubMed Central

Dutta, Siddhartha; Mohanty, Sasmita; Tripathy, Baishnab C.

2009-01-01

Modulation of photosynthesis and chloroplast biogenesis, by low and high temperatures, was studied in 12-d-old pea (Pisum sativum) plants grown at 25°C and subsequently exposed to 7°C or 40°C up to 48 h. The decline in variable chlorophyll a fluorescence/maximum chlorophyll a fluorescence and estimated electron transport rate in temperature-stressed plants was substantially restored when they were transferred to room temperature. The ATP-driven import of precursor of small subunit of Rubisco (pRSS) into plastids was down-regulated by 67% and 49% in heat-stressed and chill-stressed plants, respectively. Reduction in binding of the pRSS to the chloroplast envelope membranes in heat-stressed plants could be due to the down-regulation of Toc159 gene/protein expression. In addition to impaired binding, reduced protein import into chloroplast in heat-stressed plants was likely due to decreased gene/protein expression of certain components of the TOC complex (Toc75), the TIC complex (Tic20, Tic32, Tic55, and Tic62), stromal Hsp93, and stromal processing peptidase. In chill-stressed plants, the gene/protein expression of most of the components of protein import apparatus other than Tic110 and Tic40 were not affected, suggesting the central role of Tic110 and Tic40 in inhibition of protein import at low temperature. Heating of intact chloroplasts at 35°C for 10 min inhibited protein import, implying a low thermal stability of the protein import apparatus. Results demonstrate that in addition to decreased gene and protein expression, down-regulation of photosynthesis in temperature-stressed plants is caused by reduced posttranslational import of plastidic proteins required for the replacement of impaired proteins coded by nuclear genome. PMID:19403728

Reducing university students' stress through a drop-in canine-therapy program.

PubMed

Binfet, John-Tyler; Passmore, Holli-Anne; Cebry, Alex; Struik, Kathryn; McKay, Carson

2018-06-01

Increasingly colleges and universities are offering canine therapy to help students de-stress as a means of supporting students' emotional health and mental well-being. Despite the popularity of such programs, there remains a dearth of research attesting to their benefits. Participants included 1960 students at a mid-size western Canadian University. The study's aims were to assess the stress-reducing effects of a weekly drop-in, canine-therapy program and to identify how long participants spent with therapy canines to reduce their stress. Demographic information was gathered, length of visit documented and a visual analog scale (VAS) was used to assess entry and exit self-reports of stress. Participants' self-reported stress levels were significantly lower after the canine therapy intervention. Participants spent an average of 35 min per session. This study supports the use of drop-in, canine therapy as a means of reducing university students' stress. The findings hold applied significance for both counseling and animal therapy practitioners regarding the dose intervention participants seek to reduce their stress.

The Arabidopsis PLAT domain protein1 is critically involved in abiotic stress tolerance.

PubMed

Hyun, Tae Kyung; van der Graaff, Eric; Albacete, Alfonso; Eom, Seung Hee; Großkinsky, Dominik K; Böhm, Hannah; Janschek, Ursula; Rim, Yeonggil; Ali, Walid Wahid; Kim, Soo Young; Roitsch, Thomas

2014-01-01

Despite the completion of the Arabidopsis genome sequence, for only a relatively low percentage of the encoded proteins experimental evidence concerning their function is available. Plant proteins that harbour a single PLAT (Polycystin, Lipoxygenase, Alpha-toxin and Triacylglycerol lipase) domain and belong to the PLAT-plant-stress protein family are ubiquitously present in monocot and dicots. However, the function of PLAT-plant-stress proteins is still poorly understood. Therefore, we have assessed the function of the uncharacterised Arabidopsis PLAT-plant-stress family members through a combination of functional genetic and physiological approaches. PLAT1 overexpression conferred increased abiotic stress tolerance, including cold, drought and salt stress, while loss-of-function resulted in opposite effects on abiotic stress tolerance. Strikingly, PLAT1 promoted growth under non-stressed conditions. Abiotic stress treatments induced PLAT1 expression and caused expansion of its expression domain. The ABF/ABRE transcription factors, which are positive mediators of abscisic acid signalling, activate PLAT1 promoter activity in transactivation assays and directly bind to the ABRE elements located in this promoter in electrophoretic mobility shift assays. This suggests that PLAT1 represents a novel downstream target of the abscisic acid signalling pathway. Thus, we showed that PLAT1 critically functions as positive regulator of abiotic stress tolerance, but also is involved in regulating plant growth, and thereby assigned a function to this previously uncharacterised PLAT domain protein. The functional data obtained for PLAT1 support that PLAT-plant-stress proteins in general could be promising targets for improving abiotic stress tolerance without yield penalty.

The Arabidopsis PLAT Domain Protein1 Is Critically Involved in Abiotic Stress Tolerance

PubMed Central

Eom, Seung Hee; Großkinsky, Dominik K.; Böhm, Hannah; Janschek, Ursula; Rim, Yeonggil; Ali, Walid Wahid; Kim, Soo Young; Roitsch, Thomas

2014-01-01

Despite the completion of the Arabidopsis genome sequence, for only a relatively low percentage of the encoded proteins experimental evidence concerning their function is available. Plant proteins that harbour a single PLAT (Polycystin, Lipoxygenase, Alpha-toxin and Triacylglycerol lipase) domain and belong to the PLAT-plant-stress protein family are ubiquitously present in monocot and dicots. However, the function of PLAT-plant-stress proteins is still poorly understood. Therefore, we have assessed the function of the uncharacterised Arabidopsis PLAT-plant-stress family members through a combination of functional genetic and physiological approaches. PLAT1 overexpression conferred increased abiotic stress tolerance, including cold, drought and salt stress, while loss-of-function resulted in opposite effects on abiotic stress tolerance. Strikingly, PLAT1 promoted growth under non-stressed conditions. Abiotic stress treatments induced PLAT1 expression and caused expansion of its expression domain. The ABF/ABRE transcription factors, which are positive mediators of abscisic acid signalling, activate PLAT1 promoter activity in transactivation assays and directly bind to the ABRE elements located in this promoter in electrophoretic mobility shift assays. This suggests that PLAT1 represents a novel downstream target of the abscisic acid signalling pathway. Thus, we showed that PLAT1 critically functions as positive regulator of abiotic stress tolerance, but also is involved in regulating plant growth, and thereby assigned a function to this previously uncharacterised PLAT domain protein. The functional data obtained for PLAT1 support that PLAT-plant-stress proteins in general could be promising targets for improving abiotic stress tolerance without yield penalty. PMID:25396746

Effects of heat, cold, acid and bile salt adaptations on the stress tolerance and protein expression of kefir-isolated probiotic Lactobacillus kefiranofaciens M1.

PubMed

Chen, Ming-Ju; Tang, Hsin-Yu; Chiang, Ming-Lun

2017-09-01

Lactobacillus kefiranofaciens M1 is a probiotic strain isolated from Taiwanese kefir grains. The present study evaluated the effects of heat, cold, acid and bile salt adaptations on the stress tolerance of L. kefiranofaciens M1. The regulation of protein expression of L. kefiranofaciens M1 under these adaptation conditions was also investigated. The results showed that adaptation of L. kefiranofaciens M1 to heat, cold, acid and bile salts induced homologous tolerance and cross-protection against heterologous challenge. The extent of induced tolerance varied depending on the type and condition of stress. Proteomic analysis revealed that 27 proteins exhibited differences in expression between non-adapted and stress-adapted L. kefiranofaciens M1 cells. Among these proteins, three proteins involved in carbohydrate metabolism (triosephosphate isomerase, enolase and NAD-dependent glycerol-3-phosphate dehydrogenase), two proteins involved in pH homeostasis (ATP synthase subunits AtpA and AtpB), two stress response proteins (chaperones DnaK and GroEL) and one translation-related protein (30S ribosomal protein S2) were up-regulated by three of the four adaptation treatments examined. The increased synthesis of these stress proteins might play a critical protective role in the cellular defense against heat, cold, acid and bile salt stresses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of Integrated Responses to Nonlethal and Lethal Hypothermal Stress in Milkfish (Chanos chanos): A Proteomics Study.

PubMed

Chang, Chia-Hao; Tang, Cheng-Hao; Kang, Chao-Kai; Lo, Wan-Yu; Lee, Tsung-Han

Milkfish is an important aquaculture species in Taiwan, and its high mortality during cold snaps in winter usually causes huge economic losses. To understand the effect of hypothermal stress and the corresponding compensatory stress response in milkfish, this study aimed to compare liver and gill protein levels between milkfish exposed to nonlethal (18°C), lethal (16°C), and control (28°C) temperatures. Using a proteomics approach based on two-dimensional electrophoresis and nano-LC-MS/MS analysis, this study identified thirty unique protein spots from milkfish livers and gills for which protein abundance was significantly different between nonlethal, lethal, and control temperature groups. Proteins identified in the liver were classified into three different categories according to their cellular function: (1) anti-oxidative stress, (2) apoptotic pathway, and (3) cytoskeleton. Similarly, proteins identified in the gill were sorted in five different functional categories: (1) cytoskeleton, (2) immune response, (3) protein quality control, (4) energy production, and (5) intracellular homeostasis. Based on functional information derived from the identified proteins, we assumed that different levels of hypothermal stress had a different effect and induced a different cellular response. Upon nonlethal hypothermal stress, the identified proteins were involved in anti-oxidative stress and anti-inflammation pathways, suggesting that milkfish had high levels of oxidative stress in the liver and exhibited inflammation response in the gill. Upon lethal hypothermal stress, however, identified proteins were associated with apoptosis in the liver and regulation of intracellular homeostasis in the gill. The present study provided evidence to illustrate different multi-physiological responses to nonlethal and lethal hypothermal stress in milkfish livers and gills.

Comparison of Integrated Responses to Nonlethal and Lethal Hypothermal Stress in Milkfish (Chanos chanos): A Proteomics Study

PubMed Central

Chang, Chia-Hao; Tang, Cheng-Hao; Kang, Chao-Kai; Lo, Wan-Yu; Lee, Tsung-Han

2016-01-01

Milkfish is an important aquaculture species in Taiwan, and its high mortality during cold snaps in winter usually causes huge economic losses. To understand the effect of hypothermal stress and the corresponding compensatory stress response in milkfish, this study aimed to compare liver and gill protein levels between milkfish exposed to nonlethal (18°C), lethal (16°C), and control (28°C) temperatures. Using a proteomics approach based on two-dimensional electrophoresis and nano-LC-MS/MS analysis, this study identified thirty unique protein spots from milkfish livers and gills for which protein abundance was significantly different between nonlethal, lethal, and control temperature groups. Proteins identified in the liver were classified into three different categories according to their cellular function: (1) anti-oxidative stress, (2) apoptotic pathway, and (3) cytoskeleton. Similarly, proteins identified in the gill were sorted in five different functional categories: (1) cytoskeleton, (2) immune response, (3) protein quality control, (4) energy production, and (5) intracellular homeostasis. Based on functional information derived from the identified proteins, we assumed that different levels of hypothermal stress had a different effect and induced a different cellular response. Upon nonlethal hypothermal stress, the identified proteins were involved in anti-oxidative stress and anti-inflammation pathways, suggesting that milkfish had high levels of oxidative stress in the liver and exhibited inflammation response in the gill. Upon lethal hypothermal stress, however, identified proteins were associated with apoptosis in the liver and regulation of intracellular homeostasis in the gill. The present study provided evidence to illustrate different multi-physiological responses to nonlethal and lethal hypothermal stress in milkfish livers and gills. PMID:27657931

Quantitative Proteomics Reveals the Flooding-Tolerance Mechanism in Mutant and Abscisic Acid-Treated Soybean.

PubMed

Yin, Xiaojian; Nishimura, Minoru; Hajika, Makita; Komatsu, Setsuko

2016-06-03

Flooding negatively affects the growth of soybean, and several flooding-specific stress responses have been identified; however, the mechanisms underlying flooding tolerance in soybean remain unclear. To explore the initial flooding tolerance mechanisms in soybean, flooding-tolerant mutant and abscisic acid (ABA)-treated plants were analyzed. In the mutant and ABA-treated soybeans, 146 proteins were commonly changed at the initial flooding stress. Among the identified proteins, protein synthesis-related proteins, including nascent polypeptide-associated complex and chaperonin 20, and RNA regulation-related proteins were increased in abundance both at protein and mRNA expression. However, these proteins identified at the initial flooding stress were not significantly changed during survival stages under continuous flooding. Cluster analysis indicated that glycolysis- and cell wall-related proteins, such as enolase and polygalacturonase inhibiting protein, were increased in abundance during survival stages. Furthermore, lignification of root tissue was improved even under flooding stress. Taken together, these results suggest that protein synthesis- and RNA regulation-related proteins play a key role in triggering tolerance to the initial flooding stress in soybean. Furthermore, the integrity of cell wall and balance of glycolysis might be important factors for promoting tolerance of soybean root to flooding stress during survival stages.

Erianthus arundinaceus HSP70 (EaHSP70) Acts as a Key Regulator in the Formation of Anisotropic Interdigitation in Sugarcane (Saccharum spp. hybrid) in Response to Drought Stress.

PubMed

Augustine, Sruthy Maria; Cherian, Anoop V; Syamaladevi, Divya P; Subramonian, N

2015-12-01

Plant growth during abiotic stress is a long sought-after trait especially in crop plants in the context of global warming and climate change. Previous studies on leaf epidermal cells have revealed that during normal growth and development, adjacent cells interdigitate anisotropically to form cell morphological patterns known as interlocking marginal lobes (IMLs), involving the cell wall-cell membrane-cortical actin continuum. IMLs are growth-associated cell morphological changes in which auxin-binding protein (ABP), Rho GTPases and actin are known to play important roles. In the present study, we investigated the formation of IMLs under drought stress and found that Erianthus arundinaceus, a drought-tolerant wild relative of sugarcane, develops such growth-related cell morphological patterns under drought stress. Using confocal microscopy, we showed an increasing trend in cortical F-actin intensity in drought-tolerant plants with increasing soil moisture stress. In order to check the role of drought tolerance-related genes in IML formation under soil moisture stress, we adopted a structural data mining strategy and identified indirect connections between the ABPs and heat shock proteins (HSPs). Initial experimental evidence for this connection comes from the high transcript levels of HSP70 observed in drought-stressed Erianthus, which developed anisotropic interdigitation, i.e. IMLs. Subsequently, by overexpressing the E. arundinaceus HSP70 gene (EaHSP70) in sugarcane (Saccharum spp. hybrid), we confirm the role of HSP70 in the formation of anisotropic interdigitation under drought stress. Taken together, our results suggest that EaHSP70 acts as a key regulator in the formation of anisotropic interdigitation in drought-tolerant plants (Erianthus and HSP70 transgenic sugarcane) under moisture stress in an actin-mediated pathway. The possible biological significance of the formation of drought-associated interlocking marginal lobes (DaIMLs) in sugarcane plants upon drought stress is discussed. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

MSU-DOE Plant Research Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-01-01

This document is the compiled progress reports of research funded through the Michigan State University/Department of Energy Plant Research Laboratory. Fourteen reports are included, covering the molecular basis of plant/microbe symbiosis, cell wall biosynthesis and proteins, gene expression, stress responses, plant hormone biosynthesis, interactions between the nuclear and organelle genomes, sensory transduction and tropisms, intracellular sorting and trafficking, regulation of lipid metabolism, molecular basis of disease resistance and plant pathogenesis, developmental biology of Cyanobacteria, and hormonal involvement in environmental control of plant growth. 320 refs., 26 figs., 3 tabs. (MHB)

Changes in protein expression in testes of L2 strain Taiwan country chickens in response to acute heat stress.

PubMed

Wang, Shih-Han; Cheng, Chuen-Yu; Chen, Chao-Jung; Chen, Hsin-Hsin; Tang, Pin-Chi; Chen, Chih-Feng; Lee, Yen-Pai; Huang, San-Yuan

2014-07-01

Heat stress causes a decrease of fertility in roosters. Yet, the way acute heat stress affects protein expression remains poorly understood. This study investigated differential protein expression in testes of the L2 strain of Taiwan country chickens following acute heat stress. Twelve 45-week-old roosters were allocated into four groups, including control roosters kept at 25 °C, roosters subjected to 38 °C acute heat stress for 4 hours without recovery, with 2 hours of recovery, and with 6 hours of recovery. Testis samples were collected for morphologic assay and protein analysis. Some of the differentially expressed proteins were validated by Western blot and immunohistochemistry. Abnormal and apoptotic spermatogenic cells were observed at 2 hours of recovery after acute heat stress, especially among the spermatocytes. Two-dimensional difference gel electrophoresis revealed that 119 protein spots were differentially expressed in chicken testes following heat stress, and peptide mass fingerprinting revealed that these spots contained 92 distinct proteins. In the heat-stressed samples, the heat shock proteins, chaperonin containing t-complex, and proteasome subunits were downregulated, and glutathione S-transferase, transgelin, and DJ-1 were upregulated. Our results demonstrate that acute heat stress impairs the processes of translation, protein folding, and protein degradation, and thus results in apoptosis and interferes with spermatogenesis. On the other hand, the increased expression of antioxidant enzymes, including glutathione S-transferase and DJ-1, may attenuate heat-induced damage. These findings may have implications for breeding chickens that can tolerate more extreme conditions. Copyright © 2014 Elsevier Inc. All rights reserved.

Genome-Wide Association Mapping Combined with Reverse Genetics Identifies New Effectors of Low Water Potential-Induced Proline Accumulation in Arabidopsis1[W][OPEN

PubMed Central

Verslues, Paul E.; Lasky, Jesse R.; Juenger, Thomas E.; Liu, Tzu-Wen; Kumar, M. Nagaraj

2014-01-01

Arabidopsis (Arabidopsis thaliana) exhibits natural genetic variation in drought response, including varying levels of proline (Pro) accumulation under low water potential. As Pro accumulation is potentially important for stress tolerance and cellular redox control, we conducted a genome-wide association (GWAS) study of low water potential-induced Pro accumulation using a panel of natural accessions and publicly available single-nucleotide polymorphism (SNP) data sets. Candidate genomic regions were prioritized for subsequent study using metrics considering both the strength and spatial clustering of the association signal. These analyses found many candidate regions likely containing gene(s) influencing Pro accumulation. Reverse genetic analysis of several candidates identified new Pro effector genes, including thioredoxins and several genes encoding Universal Stress Protein A domain proteins. These new Pro effector genes further link Pro accumulation to cellular redox and energy status. Additional new Pro effector genes found include the mitochondrial protease LON1, ribosomal protein RPL24A, protein phosphatase 2A subunit A3, a MADS box protein, and a nucleoside triphosphate hydrolase. Several of these new Pro effector genes were from regions with multiple SNPs, each having moderate association with Pro accumulation. This pattern supports the use of summary approaches that incorporate clusters of SNP associations in addition to consideration of individual SNP probability values. Further GWAS-guided reverse genetics promises to find additional effectors of Pro accumulation. The combination of GWAS and reverse genetics to efficiently identify new effector genes may be especially applicable for traits difficult to analyze by other genetic screening methods. PMID:24218491

Bioorthogonal Noncanonical Amino Acid Tagging (BONCAT) Enables Time-Resolved Analysis of Protein Synthesis in Native Plant Tissue1[OPEN

PubMed Central

Moradian, Annie

2017-01-01

Proteomic plasticity undergirds stress responses in plants, and understanding such responses requires accurate measurement of the extent to which proteins levels are adjusted to counter external stimuli. Here, we adapt bioorthogonal noncanonical amino acid tagging (BONCAT) to interrogate protein synthesis in vegetative Arabidopsis (Arabidopsis thaliana) seedlings. BONCAT relies on the translational incorporation of a noncanonical amino acid probe into cellular proteins. In this study, the probe is the Met surrogate azidohomoalanine (Aha), which carries a reactive azide moiety in its amino acid side chain. The azide handle in Aha can be selectively conjugated to dyes and functionalized beads to enable visualization and enrichment of newly synthesized proteins. We show that BONCAT is sensitive enough to detect Arabidopsis proteins synthesized within a 30-min interval defined by an Aha pulse and that the method can be used to detect proteins made under conditions of light stress, osmotic shock, salt stress, heat stress, and recovery from heat stress. We further establish that BONCAT can be coupled to tandem liquid chromatography-mass spectrometry to identify and quantify proteins synthesized during heat stress and recovery from heat stress. Our results are consistent with a model in which, upon the onset of heat stress, translation is rapidly reprogrammed to enhance the synthesis of stress mitigators and is again altered during recovery. All experiments were carried out with commercially available reagents, highlighting the accessibility of the BONCAT method to researchers interested in stress responses as well as translational and posttranslational regulation in plants. PMID:28104718

Biological Networks Underlying Abiotic Stress Tolerance in Temperate Crops—A Proteomic Perspective

PubMed Central

Kosová, Klára; Vítámvás, Pavel; Urban, Milan Oldřich; Klíma, Miroslav; Roy, Amitava; Prášil, Ilja Tom

2015-01-01

Abiotic stress factors, especially low temperatures, drought, and salinity, represent the major constraints limiting agricultural production in temperate climate. Under the conditions of global climate change, the risk of damaging effects of abiotic stresses on crop production increases. Plant stress response represents an active process aimed at an establishment of novel homeostasis under altered environmental conditions. Proteins play a crucial role in plant stress response since they are directly involved in shaping the final phenotype. In the review, results of proteomic studies focused on stress response of major crops grown in temperate climate including cereals: common wheat (Triticum aestivum), durum wheat (Triticum durum), barley (Hordeum vulgare), maize (Zea mays); leguminous plants: alfalfa (Medicago sativa), soybean (Glycine max), common bean (Phaseolus vulgaris), pea (Pisum sativum); oilseed rape (Brassica napus); potato (Solanum tuberosum); tobacco (Nicotiana tabaccum); tomato (Lycopersicon esculentum); and others, to a wide range of abiotic stresses (cold, drought, salinity, heat, imbalances in mineral nutrition and heavy metals) are summarized. The dynamics of changes in various protein functional groups including signaling and regulatory proteins, transcription factors, proteins involved in protein metabolism, amino acid metabolism, metabolism of several stress-related compounds, proteins with chaperone and protective functions as well as structural proteins (cell wall components, cytoskeleton) are briefly overviewed. Attention is paid to the differences found between differentially tolerant genotypes. In addition, proteomic studies aimed at proteomic investigation of multiple stress factors are discussed. In conclusion, contribution of proteomic studies to understanding the complexity of crop response to abiotic stresses as well as possibilities to identify and utilize protein markers in crop breeding processes are discussed. PMID:26340626

The constant threat of terrorism: stress levels and coping strategies amongst university students of Karachi.

PubMed

Ahmed, Ayesha Ejaz; Masood, Komal; Dean, Sohni Vicky; Shakir, Tanzila; Kardar, Ahmed Abdul Hafeez; Barlass, Usman; Imam, Syed Haider; Mohmand, Mohammad Ghawar Khan; Ibrahim, Hussain; Khan, Imad Saeed; Akram, Usman; Hasnain, Farid

2011-04-01

To assess the levels of stress in the face of terrorism and the adopted coping strategies, amongst the student population of universities in Karachi. A descriptive, cross sectional study was conducted on undergraduate students from four universities of Karachi. Self-administered questionnaires were filled out by 291 students. Pearson Chi-Square test was used to assess associations between stress levels and different variables at a level of significance of 0.05%. A total of 65.8% of the students had mild stress levels, 91.5% of university students were exposed to terrorism through television, while only 26.5% students reported personal exposure to terrorism. 67.4% students were forbidden by their parents to go out (p = 0.002). Most of those who had self exposure to an attack were the ones whose parents forbade them from going out (p = 0.00). Most commonly used coping strategy was increased faith in religion. Irritability was the most common stress symptom. A majority of students studying in universities of Karachi had mild stress levels due to the constant threat of terrorism whereas a minority had severe stress levels. Possible reasons for resilience and only mild stress levels could be the history of Karachi's internal conflicts and its prolonged duration of being exposed to terrorism. These students who are positive for stress need to be targeted for counseling either through the media or through their universities. More extensive research is needed in this area.

Localization of SERBP1 in stress granules and nucleoli.

PubMed

Lee, Yu-Jen; Wei, Hung-Ming; Chen, Ling-Yun; Li, Chuan

2014-01-01

SERPINE1 mRNA-binding protein 1 (SERBP1) is an arginine-methylated RNA-binding protein whose modification affects protein interaction and intracellular localization. In the present study, we show that, under normal growth conditions without stress, SERBP1 interacts with arginine-methylated and stress granule-associated proteins such as heterogeneous nuclear ribonucleoprotein A1, fragile X mental retardation protein and fragile X mental retardation syndrome-related protein 1 in an RNA-dependent manner. We also show that, after arsenite treatment, a proportion of full-length SERBP1 protein co-localizes with the typical stress granule marker T-cell intracellular antigen-1 in the cytoplasmic stress granules. Truncated SERBP1 with an N-terminal, central RG or C-terminal deletion, or single-domain segments comprising the N-terminal, central or C-terminal region, were recruited to stress granules upon arsenite treatment but with reduced efficiency. In addition, upon arsenite treatment, the localization of SERBP1 changed from a diffuse cytoplasmic localization to nuclear-dominant (concentrated in the nucleolus) A similar distribution was observed when cells were treated with the methylation inhibitor adenosine periodate, and was also detected for N- or C-terminal domain deletions and all three single-domain fragments even without stress induction. We further demonstrate that adenosine periodate treatment delays the association/dissociation of SERBP1 with stress granules. Hypomethylation retains SERBP1 in the nucleus/nucleolus regardless of arsenite treatment. Our study indicates that arginine methylation is correlated with recruitment of SERBP to stress granules and nucleoli and its retention therein. To our knowledge, this is the first report of an RNA-binding protein that is shifted simultaneously to cytoplasmic stress granules and nucleoli, two ribonucleoprotein-enriched subcellular compartments, upon stress. © 2013 FEBS.

Identification of differentially accumulated proteins involved in regulating independent and combined osmosis and cadmium stress response in Brachypodium seedling roots.

PubMed

Chen, Ziyan; Zhu, Dong; Wu, Jisu; Cheng, Zhiwei; Yan, Xing; Deng, Xiong; Yan, Yueming

2018-05-17

In this study, we aimed to identify differentially accumulated proteins (DAPs) involved in PEG mock osmotic stress, cadmium (Cd 2+ ) stress, and their combined stress responses in Brachypodium distachyon seedling roots. The results showed that combined PEG and Cd 2+ stresses had more significant effects on Brachypodium seedling root growth, physiological traits, and ultrastructures when compared with each individual stress. Totally, 106 DAPs were identified that are responsive to individual and combined stresses in roots. These DAPs were mainly involved in energy metabolism, detoxification and stress defense and protein metabolism. Principal component analysis revealed that DAPs from Cd 2+ and combined stress treatments were grouped closer than those from osmotic stress treatment, indicating that Cd 2+ and combined stresses had more severe influences on the root proteome than osmotic stress alone. Protein-protein interaction analyses highlighted a 14-3-3 centered sub-network that synergistically responded to osmotic and Cd 2+ stresses and their combined stresses. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis of 14 key DAP genes revealed that most genes showed consistency between transcriptional and translational expression patterns. A putative pathway of proteome metabolic changes in Brachypodium seedling roots under different stresses was proposed, which revealed a complicated synergetic responsive network of plant roots to adverse environments.

Occupational stress and its related factors among university teachers in China.

PubMed

Sun, Wei; Wu, Hui; Wang, Lie

2011-01-01

University teachers in China are expected to suffer serious occupational stress due to the expanding enrollment in universities without a proportional increase in teacher resources and the fact that all promotions for university teachers are determined based on not only teaching but also the outcome of scientific research. This study was designed to assess the occupational stress among university teachers in China and clarify its risk factors. A cross-sectional study was performed in Liaoning Province, the centralized area of higher education in Northeast China. Eight universities (2 multidiscipline and 6 specialized) and 10% of academic staff each were randomly sampled. Questionnaires pertaining to occupational stress indicated by the Chinese Version Personal Strain Questionnaire (PSQ) and demographic characteristics, health status, work situations, and personal and social resources were distributed in October 2008. A total of 827 effective respondents (response rate 76.4%) became our participants. The average raw score of PSQ was 91.0 among the university teachers. General linear model analysis showed that the factors significantly associated with the PSQ score were, in standardized estimate (β) sequence, mental health, role overload, role insufficiency, social support, monthly income, role limitations due to physical problems, research finance and self-rated disease with adjustment for age and sex. We concluded that, in comparison to work-related factors and social support, mental health is a prominent risk factor for occupational stress in university teachers in China. Improvement of mental health and organizational climate should be considered to lessen the occupational stress of university teachers.

Proteomics Analysis of Alfalfa Response to Heat Stress

PubMed Central

Li, Weimin; Wei, Zhenwu; Qiao, Zhihong; Wu, Zinian; Cheng, Lixiang; Wang, Yuyang

2013-01-01

The proteome responses to heat stress have not been well understood. In this study, alfalfa (Medicago sativa L. cv. Huaiyin) seedlings were exposed to 25°C (control) and 40°C (heat stress) in growth chambers, and leaves were collected at 24, 48 and 72 h after treatment, respectively. The morphological, physiological and proteomic processes were negatively affected under heat stress. Proteins were extracted and separated by two-dimensional polyacrylamide gel electrophoresis (2-DE), and differentially expressed protein spots were identified by mass spectrometry (MS). Totally, 81 differentially expressed proteins were identified successfully by MALDI-TOF/TOF. These proteins were categorized into nine classes: including metabolism, energy, protein synthesis, protein destination/storage, transporters, intracellular traffic, cell structure, signal transduction and disease/defence. Five proteins were further analyzed for mRNA levels. The results of the proteomics analyses provide a better understanding of the molecular basis of heat-stress responses in alfalfa. PMID:24324825

Comparative proteomic responses of two bermudagrass (Cynodon dactylon (L). Pers.) varieties contrasting in drought stress resistance.

PubMed

Shi, Haitao; Ye, Tiantian; Chan, Zhulong

2014-09-01

Drought (water-deficit) stress is a serious environmental problem in plant growth and cultivation. As one of widely cultivated warm-season turfgrass, bermudagrass (Cynodon dactylon (L). Pers.) exhibits drastic natural variation in the drought stress resistance in leaves and stems of different varieties. In this study, proteomic analysis was performed to identify drought-responsive proteins in both leaves and stems of two bermudagrass varieties contrasting in drought stress resistance, including drought sensitive variety (Yukon) and drought tolerant variety (Tifgreen). Through comparative proteomic analysis, 39 proteins with significantly changed abundance were identified, including 3 commonly increased and 2 decreased proteins by drought stress in leaves and stems of Yukon and Tifgreen varieties, 2 differentially regulated proteins in leaves and stems of two varieties after drought treatment, 23 proteins increased by drought stress in Yukon variety and constitutively expressed in Tifgreen variety, and other 3 differentially expressed proteins under control and drought stress conditions. Among them, proteins involved in photosynthesis (PS), glycolysis, N-metabolism, tricarboxylicacid (TCA) and redox pathways were largely enriched, which might be contributed to the natural variation of drought resistance between Yukon and Tifgreen varieties. These studies provide new insights to understand the molecular mechanism underlying bermudagrass response to drought stress. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Quantitative proteomic analysis of cabernet sauvignon grape cells exposed to thermal stresses reveals alterations in sugar and phenylpropanoid metabolism.

PubMed

George, Iniga S; Pascovici, Dana; Mirzaei, Mehdi; Haynes, Paul A

2015-09-01

Grapes (Vitis vinifera) are a valuable fruit crop and wine production is a major industry. Global warming and expanded range of cultivation will expose grapes to more temperature stresses in future. Our study investigated protein level responses to abiotic stresses, with particular reference to proteomic changes induced by the impact of four different temperature stress regimes, including both hot and cold temperatures, on cultured grape cells. Cabernet Sauvignon cell suspension cultures grown at 26°C were subjected to 14 h of exposure to 34 and 42°C for heat stress, and 18 and 10°C for cold stress. Cells from the five temperatures were harvested in biological triplicates and label-free quantitative shotgun proteomic analysis was performed. A total of 2042 non-redundant proteins were identified from the five temperature points. Fifty-five proteins were only detected in extreme heat stress conditions (42°C) and 53 proteins were only detected at extreme cold stress conditions (10°C). Gene Ontology (GO) annotations of differentially expressed proteins provided insights into the metabolic pathways that are involved in temperature stress in grape cells. Sugar metabolism displayed switching between alternative and classical pathways during temperature stresses. Additionally, nine proteins involved in the phenylpropanoid pathway were greatly increased in abundance at extreme cold stress, and were thus found to be cold-responsive proteins. All MS data have been deposited in the ProteomeXchange with identifier PXD000977 (http://proteomecentral.proteomexchange.org/dataset/PXD000977). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nuclear localization of the C2H2 zinc finger protein Msn2p is regulated by stress and protein kinase A activity

PubMed Central

Görner, Wolfram; Durchschlag, Erich; Martinez-Pastor, Maria Teresa; Estruch, Francisco; Ammerer, Gustav; Hamilton, Barbara; Ruis, Helmut; Schüller, Christoph

1998-01-01

Msn2p and the partially redundant factor Msn4p are key regulators of stress-responsive gene expression in Saccharomyces cerevisiae. They are required for the transcription of a number of genes coding for proteins with stress-protective functions. Both Msn2p and Msn4p are Cys2His2 zinc finger proteins and bind to the stress response element (STRE). In vivo footprinting studies show that the occupation of STREs is enhanced in stressed cells and dependent on the presence of Msn2p and Msn4p. Both factors accumulate in the nucleus under stress conditions, such as heat shock, osmotic stress, carbon-source starvation, and in the presence of ethanol or sorbate. Stress-induced nuclear localization was found to be rapid, reversible, and independent of protein synthesis. Nuclear localization of Msn2p and Msn4p was shown to be correlated inversely to cAMP levels and protein kinase A (PKA) activity. A region with significant homologies shared between Msn2p and Msn4p is sufficient to confer stress-regulated localization to a SV40–NLS–GFP fusion protein. Serine to alanine or aspartate substitutions in a conserved PKA consensus site abolished cAMP-driven nuclear export and cytoplasmic localization in unstressed cells. We propose stress and cAMP-regulated intracellular localization of Msn2p to be a key step in STRE-dependent transcription and in the general stress response. PMID:9472026

Perceived sources of stress among Malaysian dental students

PubMed Central

Hasan, Syed S.; Ooi, Yong J.; Ahmed, Syed I.; Wong, Pei S.; Ahmad, Siti F.; MNM-Rosdy, Nik M.; Malik, Normaliza A.

2015-01-01

Objectives The study objectives were to identify the stress levels and to explore the impact of students' year of study and gender on the perceived sources of stress among Malaysian dental students. Methods This was a cross-sectional study involving dental students from year one to year five from private and public universities in Malaysia. The study was formally approved by the Research and Ethics Committee, International Medical University Malaysia. Dental Environment Stress (DES) questionnaire was used for data collection and the gathered data were analyzed using SPSS® version 18. The Kruskal-Wallis and the Mann-Whitney U tests were used to compare stress items across various academic years and universities. Results A total of five hundred and twenty nine (529) students participated in this study. Fear of failing the course at the end of year exams (mean stress level=5.57); concerns regarding completion of clinical work (mean=5.30); and examination results and grades (mean=5.27) were found as top stressors among dental students. Female students had higher stress scores than males with respect to personal issues, academic performance, educational environment and learning of clinical skills. Students from public universities had higher stress scores than their counterparts from private universities. Conclusion The Malaysian dental students reported higher levels of stress. Present study identified stressors affecting dental students' academic life, and highlights the importance of stress management programs and other measures to minimize the impact of stress on both academic and personal lives of the students. PMID:25935506

Perceived sources of stress among Malaysian dental students.

PubMed

Babar, Muneer G; Hasan, Syed S; Ooi, Yong J; Ahmed, Syed I; Wong, Pei S; Ahmad, Siti F; Mnm-Rosdy, Nik M; Malik, Normaliza A

2015-05-02

The study objectives were to identify the stress levels and to explore the impact of students' year of study and gender on the perceived sources of stress among Malaysian dental students. This was a cross-sectional study involving dental students from year one to year five from private and public universities in Malaysia. The study was formally approved by the Research and Ethics Committee, International Medical University Malaysia. Dental Environment Stress (DES) questionnaire was used for data collection and the gathered data were analyzed using SPSS® version 18. The Kruskal-Wallis and the Mann-Whitney U tests were used to compare stress items across various academic years and universities. A total of five hundred and twenty nine (529) students participated in this study. Fear of failing the course at the end of year exams (mean stress level=5.57); concerns regarding completion of clinical work (mean=5.30); and examination results and grades (mean=5.27) were found as top stressors among dental students. Female students had higher stress scores than males with respect to personal issues, academic performance, educational environment and learning of clinical skills. Students from public universities had higher stress scores than their counterparts from private universities. The Malaysian dental students reported higher levels of stress. Present study identified stressors affecting dental students' academic life, and highlights the importance of stress management programs and other measures to minimize the impact of stress on both academic and personal lives of the students.

A Network Biology Approach to Decipher Stress Response in Bacteria Using Escherichia coli As a Model.

PubMed

Nagar, Shashwat Deepali; Aggarwal, Bhavye; Joon, Shikha; Bhatnagar, Rakesh; Bhatnagar, Sonika

2016-05-01

The development of drug-resistant pathogenic bacteria poses challenges to global health for their treatment and control. In this context, stress response enables bacterial populations to survive extreme perturbations in the environment but remains poorly understood. Specific modules are activated for unique stressors with few recognized global regulators. The phenomenon of cross-stress protection strongly suggests the presence of central proteins that control the diverse stress responses. In this work, Escherichia coli was used to model the bacterial stress response. A Protein-Protein Interaction Network was generated by integrating differentially expressed genes in eight stress conditions of pH, temperature, and antibiotics with relevant gene ontology terms. Topological analysis identified 24 central proteins. The well-documented role of 16 central proteins in stress indicates central control of the response, while the remaining eight proteins may have a novel role in stress response. Cluster analysis of the generated network implicated RNA binding, flagellar assembly, ABC transporters, and DNA repair as important processes during response to stress. Pathway analysis showed crosstalk of Two Component Systems with metabolic processes, oxidative phosphorylation, and ABC transporters. The results were further validated by analysis of an independent cross-stress protection dataset. This study also reports on the ways in which bacterial stress response can progress to biofilm formation. In conclusion, we suggest that drug targets or pathways disrupting bacterial stress responses can potentially be exploited to combat antibiotic tolerance and multidrug resistance in the future.

Amelogenesis imperfecta caused by N-terminal enamelin point mutations in mice and men is driven by endoplasmic reticulum stress.

PubMed

Brookes, Steven J; Barron, Martin J; Smith, Claire E L; Poulter, James A; Mighell, Alan J; Inglehearn, Chris F; Brown, Catriona J; Rodd, Helen; Kirkham, Jennifer; Dixon, Michael J

2017-05-15

'Amelogenesis imperfecta' (AI) describes a group of inherited diseases of dental enamel that have major clinical impact. Here, we identify the aetiology driving AI in mice carrying a p.S55I mutation in enamelin; one of the most commonly mutated proteins underlying AI in humans. Our data indicate that the mutation inhibits the ameloblast secretory pathway leading to ER stress and an activated unfolded protein response (UPR). Initially, with the support of the UPR acting in pro-survival mode, Enamp.S55I heterozygous mice secreted structurally normal enamel. However, enamel secreted thereafter was structurally abnormal; presumably due to the UPR modulating ameloblast behaviour and function in an attempt to relieve ER stress. Homozygous mutant mice failed to produce enamel. We also identified a novel heterozygous ENAMp.L31R mutation causing AI in humans. We hypothesize that ER stress is the aetiological factor in this case of human AI as it shared the characteristic phenotype described above for the Enamp.S55I mouse. We previously demonstrated that AI in mice carrying the Amelxp.Y64H mutation is a proteinopathy. The current data indicate that AI in Enamp.S55I mice is also a proteinopathy, and based on comparative phenotypic analysis, we suggest that human AI resulting from the ENAMp.L31R mutation is another proteinopathic disease. Identifying a common aetiology for AI resulting from mutations in two different genes opens the way for developing pharmaceutical interventions designed to relieve ER stress or modulate the UPR during enamel development to ameliorate the clinical phenotype. © The Author 2017. Published by Oxford University Press.

Unfolded protein response activation compensates endoplasmic reticulum-associated degradation deficiency in Arabidopsis.

PubMed

Li, Qingliang; Wei, Hai; Liu, Lijing; Yang, Xiaoyuan; Zhang, Xiansheng; Xie, Qi

2017-07-01

Abiotic stresses often disrupt protein folding and induce endoplasmic reticulum (ER) stress. There is a sophisticated ER quality control (ERQC) system to mitigate the effects of malfunctioning proteins and maintain ER homeostasis. The accumulation of misfolded proteins in the ER activates the unfolded protein response (UPR) to enhance ER protein folding and the degradation of misfolded proteins mediate by ER-associated degradation (ERAD). That ERQC reduces abiotic stress damage has been well studied in mammals and yeast. However, in plants, both ERAD and UPR have been studied separately and found to be critical for plant abiotic stress tolerance. In this study, we discovered that UPR-associated transcription factors AtbZIP17, AtbZIP28 and AtbZIP60 responded to tunicamycin (TM) and NaCl induced ER stress and subsequently enhanced Arabidopsis thaliana abiotic stress tolerance. They regulated the expression level of ER chaperones and the HRD1-complex components. Moreover, overexpression of AtbZIP17, AtbZIP28 and AtbZIP60 could restore stress tolerance via ERAD in the HRD1-complex mutant hrd3a-2, which suggested that UPR and ERAD have an interactive mechanism in Arabidopsis. © 2017 Institute of Botany, Chinese Academy of Sciences.

ERK1/2 signalling protects against apoptosis following endoplasmic reticulum stress but cannot provide long-term protection against BAX/BAK-independent cell death.

PubMed

Darling, Nicola J; Balmanno, Kathryn; Cook, Simon J

2017-01-01

Disruption of protein folding in the endoplasmic reticulum (ER) causes ER stress. Activation of the unfolded protein response (UPR) acts to restore protein homeostasis or, if ER stress is severe or persistent, drive apoptosis, which is thought to proceed through the cell intrinsic, mitochondrial pathway. Indeed, cells that lack the key executioner proteins BAX and BAK are protected from ER stress-induced apoptosis. Here we show that chronic ER stress causes the progressive inhibition of the extracellular signal-regulated kinase (ERK1/2) signalling pathway. This is causally related to ER stress since reactivation of ERK1/2 can protect cells from ER stress-induced apoptosis whilst ERK1/2 pathway inhibition sensitises cells to ER stress. Furthermore, cancer cell lines harbouring constitutively active BRAFV600E are addicted to ERK1/2 signalling for protection against ER stress-induced cell death. ERK1/2 signalling normally represses the pro-death proteins BIM, BMF and PUMA and it has been proposed that ER stress induces BIM-dependent cell death. We found no evidence that ER stress increased the expression of these proteins; furthermore, BIM was not required for ER stress-induced death. Rather, ER stress caused the PERK-dependent inhibition of cap-dependent mRNA translation and the progressive loss of pro-survival proteins including BCL2, BCLXL and MCL1. Despite these observations, neither ERK1/2 activation nor loss of BAX/BAK could confer long-term clonogenic survival to cells exposed to ER stress. Thus, ER stress induces cell death by at least two biochemically and genetically distinct pathways: a classical BAX/BAK-dependent apoptotic response that can be inhibited by ERK1/2 signalling and an alternative ERK1/2- and BAX/BAK-independent cell death pathway.

Identifying Functional Mechanisms of Gene and Protein Regulatory Networks in Response to a Broader Range of Environmental Stresses

PubMed Central

Li, Cheng-Wei; Chen, Bor-Sen

2010-01-01

Cellular responses to sudden environmental stresses or physiological changes provide living organisms with the opportunity for final survival and further development. Therefore, it is an important topic to understand protective mechanisms against environmental stresses from the viewpoint of gene and protein networks. We propose two coupled nonlinear stochastic dynamic models to reconstruct stress-activated gene and protein regulatory networks via microarray data in response to environmental stresses. According to the reconstructed gene/protein networks, some possible mutual interactions, feedforward and feedback loops are found for accelerating response and filtering noises in these signaling pathways. A bow-tie core network is also identified to coordinate mutual interactions and feedforward loops, feedback inhibitions, feedback activations, and cross talks to cope efficiently with a broader range of environmental stresses with limited proteins and pathways. PMID:20454442

Chronic, long-term social stress can cause decreased microtubule protein network activity and dynamics in cerebral cortex of male Wistar rats.

PubMed

Eskandari Sedighi, Ghazaleh; Riazi, Gholam Hossein; Vaez Mahdavi, Mohammad Reza; Cheraghi, Tayebe; Atarod, Deyhim; Rafiei, Shahrbanoo

2015-03-01

Social stress is viewed as a factor in the etiology of a variety of psychopathologies such as depression and anxiety. Animal models of social stress are well developed and widely used in studying clinical and physiological effects of stress. Stress is known to significantly affect learning and memory, and this effect strongly depends on the type of stress, its intensity, and duration. It has been demonstrated that chronic and acute stress conditions can change neuronal plasticity, characterized by retraction of apical dendrites, reduction in axonogenesis, and decreased neurogenesis. Various behavioral studies have also confirmed a decrease in learning and memory upon exposure of animals to long-term chronic stress. On the other hand, the close relationship between microtubule (MT) protein network and neuroplasticity controlling system suggests the possibility of MT protein alterations in high stressful conditions. In this work, we have studied the kinetics, activity, and dynamicity changes of MT proteins in the cerebral cortex of male Wistar rats that were subjected to social instability for 35 and 100 days. Our results indicate that MT protein network dynamicity and polymerization ability is decreased under long-term (100 days) social stress conditions.

Diverse accumulation of several dehydrin-like proteins in cauliflower (Brassica oleracea var. botrytis), Arabidopsis thaliana and yellow lupin (Lupinus luteus) mitochondria under cold and heat stress.

PubMed

Rurek, Michal

2010-08-18

Dehydrins represent hydrophilic proteins acting mainly during cell dehydration and stress response. Dehydrins are generally thermostable; however, the so-called dehydrin-like (dehydrin-related) proteins show variable thermolability. Both groups immunoreact with antibodies directed against the K-segment of dehydrins. Plant mitochondrial dehydrin-like proteins are poorly characterized. The purpose of this study was to extend previous reports on plant dehydrins by comparing the level of immunoprecipitated dehydrin-like proteins in cauliflower (Brassica oleracea var. botrytis), Arabidopsis thaliana and yellow lupin (Lupinus luteus) mitochondria under cold and heat stress. All the analyzed plant species showed constitutive accumulation of thermostable mitochondrial putative dehydrins ranging from 50 to 70 kDa. The mitochondrial dehydrin-like proteins observed in cauliflower and Arabidopsis ranged from 10 to 100 kDa and in lupin imbibed seeds and hypocotyls--from 20 to 90 kDa. Cold treatment increased mainly the accumulation of 10-100 kDa cauliflower and Arabidopsis dehydrin-like proteins, in the patterns different in cauliflower leaf and inflorescence mitochondria. However, in lupin mitochondria, cold affected mainly 25-50 kDa proteins and seemed to induce the appearance of some novel dehydrin-like proteins. The influence of frost stress on cauliflower leaf mitochondrial dehydrin- like proteins was less significant. The impact of heat stress was less significant in lupin and Arabidopsis than in cauliflower inflorescence mitochondria. Cauliflower mitochondrial dehydrin-like proteins are localized mostly in the mitochondrial matrix; it seems that some of them may interact with mitochondrial membranes. All the results reveal an unexpectedly broad spectrum of dehydrin-like proteins accumulated during some abiotic stress in the mitochondria of the plant species analyzed. They display only limited similarity in size to those reported previously in maize, wheat and rye mitochondria. Some small thermolabile dehydrin-like proteins were induced under stress conditions applied and therefore they are likely to be involved in stress response.

Diverse accumulation of several dehydrin-like proteins in cauliflower (Brassica oleracea var. botrytis), Arabidopsis thaliana and yellow lupin (Lupinus luteus) mitochondria under cold and heat stress

PubMed Central

2010-01-01

Background Dehydrins represent hydrophilic proteins acting mainly during cell dehydration and stress response. Dehydrins are generally thermostable; however, the so-called dehydrin-like (dehydrin-related) proteins show variable thermolability. Both groups immunoreact with antibodies directed against the K-segment of dehydrins. Plant mitochondrial dehydrin-like proteins are poorly characterized. The purpose of this study was to extend previous reports on plant dehydrins by comparing the level of immunoprecipitated dehydrin-like proteins in cauliflower (Brassica oleracea var. botrytis), Arabidopsis thaliana and yellow lupin (Lupinus luteus) mitochondria under cold and heat stress. Results All the analyzed plant species showed constitutive accumulation of thermostable mitochondrial putative dehydrins ranging from 50 to 70 kDa. The mitochondrial dehydrin-like proteins observed in cauliflower and Arabidopsis ranged from 10 to 100 kDa and in lupin imbibed seeds and hypocotyls - from 20 to 90 kDa. Cold treatment increased mainly the accumulation of 10-100 kDa cauliflower and Arabidopsis dehydrin-like proteins, in the patterns different in cauliflower leaf and inflorescence mitochondria. However, in lupin mitochondria, cold affected mainly 25-50 kDa proteins and seemed to induce the appearance of some novel dehydrin-like proteins. The influence of frost stress on cauliflower leaf mitochondrial dehydrin- like proteins was less significant. The impact of heat stress was less significant in lupin and Arabidopsis than in cauliflower inflorescence mitochondria. Cauliflower mitochondrial dehydrin-like proteins are localized mostly in the mitochondrial matrix; it seems that some of them may interact with mitochondrial membranes. Conclusions All the results reveal an unexpectedly broad spectrum of dehydrin-like proteins accumulated during some abiotic stress in the mitochondria of the plant species analyzed. They display only limited similarity in size to those reported previously in maize, wheat and rye mitochondria. Some small thermolabile dehydrin-like proteins were induced under stress conditions applied and therefore they are likely to be involved in stress response. PMID:20718974

Proteomic and metabolomic analyses of soybean root tips under flooding stress.

PubMed

Komatsu, Setsuko; Nakamura, Takuji; Sugimoto, Yurie; Sakamoto, Kazunori

2014-01-01

Flooding is one of the serious problems for soybean plants because it inhibits growth. Proteomic and metabolomic techniques were used to determine whether proteins and metabolites are altered in the root tips of soybeans under flooding stress. Two-day-old soybean plants were flooded for 2 days, and proteins and metabolites were extracted from root tips. Flooding-responsive proteins were identified using two-dimensional- or SDS-polyacrylamide gel electrophoresis- based proteomics techniques. Using both techniques, 172 proteins increased and 105 proteins decreased in abundance in the root tips of flood-stressed soybean. The abundance of methionine synthase, heat shock cognate protein, urease, and phosphoenol pyruvate carboxylase was significantly increased by flooding stress. Furthermore, 73 flooding-responsive metabolites were identified using capillary electrophoresis-mass spectrometry. The levels of gamma-aminobutyric acid, glycine, NADH2, and phosphoenol pyruvate were increased by flooding stress. Taken together, these results suggest that synthesis of phosphoenol pyruvate by way of oxaloacetate produced in the tricarboxylic acid cycle is activated in soybean root tips in response to flooding stress, and that flooding stress also leads to modulation of the urea cycle in the root tips.

Advances in crop proteomics: PTMs of proteins under abiotic stress.

PubMed

Wu, Xiaolin; Gong, Fangping; Cao, Di; Hu, Xiuli; Wang, Wei

2016-03-01

Under natural conditions, crop plants are frequently subjected to various abiotic environmental stresses such as drought and heat wave, which may become more prevalent in the coming decades. Plant acclimation and tolerance to an abiotic stress are always associated with significant changes in PTMs of specific proteins. PTMs are important for regulating protein function, subcellular localization and protein activity and stability. Studies of plant responses to abiotic stress at the PTMs level are essential to the process of plant phenotyping for crop improvement. The ability to identify and quantify PTMs on a large-scale will contribute to a detailed protein functional characterization that will improve our understanding of the processes of crop plant stress acclimation and stress tolerance acquisition. Hundreds of PTMs have been reported, but it is impossible to review all of the possible protein modifications. In this review, we briefly summarize several main types of PTMs regarding their characteristics and detection methods, review the advances in PTMs research of crop proteomics, and highlight the importance of specific PTMs in crop response to abiotic stress. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Change of salivary stress marker concentrations during pregnancy: maternal depressive status suppress changes of those levels.

PubMed

Tsubouchi, Hiroaki; Nakai, Yuichiro; Toda, Masahiro; Morimoto, Kanehisa; Chang, Yang Sil; Ushioda, Norichika; Kaku, Shoji; Nakamura, Takafumi; Kimura, Tadashi; Shimoya, Koichiro

2011-08-01

The aim of the present study was to show changes in salivary cortisol and chromogranin A/protein concentrations as stress markers during pregnancy and to clarify the effect of chronic stress on stress markers. Salivary samples were collected from 69 pregnant women during pregnancy. Salivary cortisol levels and chromogranin A/protein titers were determined. We surveyed the women's chronic stress using the Zung self-rating depression scale and General Health Questionnaire-28. Cortisol levels in the saliva of pregnant women showed biphasic change during pregnancy. Chromogranin A/protein levels in the saliva of pregnant women increased in the second and the early third trimesters and decreased to the puerperal period. Salivary cortisol concentrations of the chronic high stress group were significantly lower compared with those of the normal group. Salivary chromogranin A/protein concentrations of the chronic high stress group were also significantly lower than those of the normal group. The titration of salivary cortisol concentrations and chromogranin A/protein levels is a useful tool to determine maternal stress levels. The elevation of cortisol and chromogranin A/protein in the saliva was suppressed in the chronic high stress group during pregnancy. © 2011 The Authors. Journal of Obstetrics and Gynaecology Research © 2011 Japan Society of Obstetrics and Gynecology.

Arabidopsis CML38, a Calcium Sensor That Localizes to Ribonucleoprotein Complexes under Hypoxia Stress1[OPEN

PubMed Central

McClintock, Carlee; Li, Tian

2016-01-01

During waterlogging and the associated oxygen deprivation stress, plants respond by the induction of adaptive programs, including the redirected expression of gene networks toward the synthesis of core hypoxia-response proteins. Among these core response proteins in Arabidopsis (Arabidopsis thaliana) is the calcium sensor CML38, a protein related to regulator of gene silencing calmodulin-like proteins (rgsCaMs). CML38 transcripts are up-regulated more than 300-fold in roots within 6 h of hypoxia treatment. Transfer DNA insertional mutants of CML38 show an enhanced sensitivity to hypoxia stress, with lowered survival and more severe inhibition of root and shoot growth. By using yellow fluorescent protein (YFP) translational fusions, CML38 protein was found to be localized to cytosolic granule structures similar in morphology to hypoxia-induced stress granules. Immunoprecipitation of CML38 from the roots of hypoxia-challenged transgenic plants harboring CML38pro::CML38:YFP followed by liquid chromatography-tandem mass spectrometry analysis revealed the presence of protein targets associated with messenger RNA ribonucleoprotein (mRNP) complexes including stress granules, which are known to accumulate as messenger RNA storage and triage centers during hypoxia. This finding is further supported by the colocalization of CML38 with the mRNP stress granule marker RNA Binding Protein 47 (RBP47) upon cotransfection of Nicotiana benthamiana leaves. Ruthenium Red treatment results in the loss of CML38 signal in cytosolic granules, suggesting that calcium is necessary for stress granule association. These results confirm that CML38 is a core hypoxia response calcium sensor protein and suggest that it serves as a potential calcium signaling target within stress granules and other mRNPs that accumulate during flooding stress responses. PMID:26634999

Using co-expression analysis and stress-based screens to uncover Arabidopsis peroxisomal proteins involved in drought response

DOE PAGES

Li, Jiying; Hu, Jianping; Bassham, Diane

2015-09-14

Peroxisomes are essential organelles that house a wide array of metabolic reactions important for plant growth and development. However, our knowledge regarding the role of peroxisomal proteins in various biological processes, including plant stress response, is still incomplete. Recent proteomic studies of plant peroxisomes significantly increased the number of known peroxisomal proteins and greatly facilitated the study of peroxisomes at the systems level. The objectives of this study were to determine whether genes that encode peroxisomal proteins with related functions are co-expressed in Arabidopsis and identify peroxisomal proteins involved in stress response using in silico analysis and mutant screens. Usingmore » microarray data from online databases, we performed hierarchical clustering analysis to generate a comprehensive view of transcript level changes for Arabidopsis peroxisomal genes during development and under abiotic and biotic stress conditions. Many genes involved in the same metabolic pathways exhibited co-expression, some genes known to be involved in stress response are regulated by the corresponding stress conditions, and function of some peroxisomal proteins could be predicted based on their coexpression pattern. Since drought caused expression changes to the highest number of genes that encode peroxisomal proteins, we subjected a subset of Arabidopsis peroxisomal mutants to a drought stress assay. Mutants of the LON2 protease and the photorespiratory enzyme hydroxypyruvate reductase 1 (HPR1) showed enhanced susceptibility to drought, suggesting the involvement of peroxisomal quality control and photorespiration in drought resistance. Lastly, our study provided a global view of how genes that encode peroxisomal proteins respond to developmental and environmental cues and began to reveal additional peroxisomal proteins involved in stress response, thus opening up new avenues to investigate the role of peroxisomes in plant adaptation to environmental stresses.« less

Development and application of an antibody-based protein microarray to assess physiological stress in grizzly bears (Ursus arctos).

PubMed

Carlson, Ruth I; Cattet, Marc R L; Sarauer, Bryan L; Nielsen, Scott E; Boulanger, John; Stenhouse, Gordon B; Janz, David M

2016-01-01

A novel antibody-based protein microarray was developed that simultaneously determines expression of 31 stress-associated proteins in skin samples collected from free-ranging grizzly bears (Ursus arctos) in Alberta, Canada. The microarray determines proteins belonging to four broad functional categories associated with stress physiology: hypothalamic-pituitary-adrenal axis proteins, apoptosis/cell cycle proteins, cellular stress/proteotoxicity proteins and oxidative stress/inflammation proteins. Small skin samples (50-100 mg) were collected from captured bears using biopsy punches. Proteins were isolated and labelled with fluorescent dyes, with labelled protein homogenates loaded onto microarrays to hybridize with antibodies. Relative protein expression was determined by comparison with a pooled standard skin sample. The assay was sensitive, requiring 80 µg of protein per sample to be run in triplicate on the microarray. Intra-array and inter-array coefficients of variation for individual proteins were generally <10 and <15%, respectively. With one exception, there were no significant differences in protein expression among skin samples collected from the neck, forelimb, hindlimb and ear in a subsample of n = 4 bears. This suggests that remotely delivered biopsy darts could be used in future sampling. Using generalized linear mixed models, certain proteins within each functional category demonstrated altered expression with respect to differences in year, season, geographical sampling location within Alberta and bear biological parameters, suggesting that these general variables may influence expression of specific proteins in the microarray. Our goal is to apply the protein microarray as a conservation physiology tool that can detect, evaluate and monitor physiological stress in grizzly bears and other species at risk over time in response to environmental change.

Mechanisms of stress-induced cellular HSP72 release: implications for exercise-induced increases in extracellular HSP72.

PubMed

Lancaster, Graeme I; Febbraio, Mark A

2005-01-01

The heat shock proteins are a family of highly conserved proteins with critical roles in maintaining cellular homeostasis and in protecting the cell from stressful conditions. While the critical intracellular roles of heat shock proteins are undisputed, evidence suggests that the cell possess the necessary machinery to actively secrete specific heat shock proteins in response to cellular stress. In this review, we firstly discuss the evidence that physical exercise induces the release of heat shock protein 72 from specific tissues in humans. Importantly, it appears as though this release is the result of an active secretory process, as opposed to non-specific processes such as cell lysis. Next we discuss recent in vitro evidence that has identified a mechanistic basis for the observation that cellular stress induces the release of a specific subset of heat shock proteins. Importantly, while the classical protein secretory pathway does not seem to be involved in the stress-induced release of HSP72, we discuss the evidence that lipid-rafts and exosomes are important mediators of the stress-induced release of HSP72.

BDNF Val66Met polymorphism is associated with higher anticipatory cortisol stress response, anxiety, and alcohol consumption in healthy adults.

PubMed

Colzato, Lorenza S; Van der Does, A J Willem; Kouwenhoven, Coen; Elzinga, Bernet M; Hommel, Bernhard

2011-11-01

The brain-derived neurotrophic factor (BDNF) is a key protein in maintaining neuronal integrity. The BDNF gene is thought to play an important role in the pathophysiology of mood and anxiety disorders. The aim of this study was to investigate, for the first time in a single study, the association between BDNF Val(66)Met polymorphism, anxiety, alcohol consumption, and cortisol stress response. 98 healthy university students (54 females and 44 males), genotyped for the Val(66)Met polymorphism, participated in a physical-stress procedure (cold pressure test, CPT) after having been informed that they would undergo a painful experience. Indices of anxiety and of stress were collected from repeated measurement of salivary cortisol, blood pressure, and heart rate. BDNF Met carriers, were more anxious during the CPT (p<0.001), drank more alcohol per week, (p<0.05), and showed significantly higher anticipatory cortisol response (p<0.05), but not in response to the CPT, than Val/Val homozygotes. The association of BDNF Val(66)Met polymorphism with HPA axis reactivity to stress was not modulated by gender. These results suggest that Met carriers are particularly sensitive in anticipating stressful events, which extends previous findings on the moderating role of the BDNF Val(66)Met polymorphism in the face of stressful life events. Copyright © 2011 Elsevier Ltd. All rights reserved.

Endoplasmic Reticulum Stress and Oxidative Stress in Cell Fate Decision and Human Disease

PubMed Central

Cao, Stewart Siyan

2014-01-01

Abstract Significance: The endoplasmic reticulum (ER) is a specialized organelle for the folding and trafficking of proteins, which is highly sensitive to changes in intracellular homeostasis and extracellular stimuli. Alterations in the protein-folding environment cause accumulation of misfolded proteins in the ER that profoundly affect a variety of cellular signaling processes, including reduction–oxidation (redox) homeostasis, energy production, inflammation, differentiation, and apoptosis. The unfolded protein response (UPR) is a collection of adaptive signaling pathways that evolved to resolve protein misfolding and restore an efficient protein-folding environment. Recent Advances: Production of reactive oxygen species (ROS) has been linked to ER stress and the UPR. ROS play a critical role in many cellular processes and can be produced in the cytosol and several organelles, including the ER and mitochondria. Studies suggest that altered redox homeostasis in the ER is sufficient to cause ER stress, which could, in turn, induce the production of ROS in the ER and mitochondria. Critical Issues: Although ER stress and oxidative stress coexist in many pathologic states, whether and how these stresses interact is unknown. It is also unclear how changes in the protein-folding environment in the ER cause oxidative stress. In addition, how ROS production and protein misfolding commit the cell to an apoptotic death and contribute to various degenerative diseases is unknown. Future Directions: A greater fundamental understanding of the mechanisms that preserve protein folding homeostasis and redox status will provide new information toward the development of novel therapeutics for many human diseases. Antioxid. Redox Signal. 21, 396–413. PMID:24702237

Impulsivity, Coping, Stress, and Problem Gambling among University Students

ERIC Educational Resources Information Center

Lightsey, Owen Richard, Jr.; Hulsey, C. Duncan

2002-01-01

The authors investigated whether coping styles moderated the relationship between (a) impulsivity and stress and (b) stress and gambling behavior and tested whether impulsive persons who use avoidant or emotion-focused coping under high-stress conditions are most likely to gamble. Among 202 university student volunteers, 33% of men but only 3% of…

Protein space: a natural method for realizing the nature of protein universe.

PubMed

Yu, Chenglong; Deng, Mo; Cheng, Shiu-Yuen; Yau, Shek-Chung; He, Rong L; Yau, Stephen S-T

2013-02-07

Current methods cannot tell us what the nature of the protein universe is concretely. They are based on different models of amino acid substitution and multiple sequence alignment which is an NP-hard problem and requires manual intervention. Protein structural analysis also gives a direction for mapping the protein universe. Unfortunately, now only a minuscule fraction of proteins' 3-dimensional structures are known. Furthermore, the phylogenetic tree representations are not unique for any existing tree construction methods. Here we develop a novel method to realize the nature of protein universe. We show the protein universe can be realized as a protein space in 60-dimensional Euclidean space using a distance based on a normalized distribution of amino acids. Every protein is in one-to-one correspondence with a point in protein space, where proteins with similar properties stay close together. Thus the distance between two points in protein space represents the biological distance of the corresponding two proteins. We also propose a natural graphical representation for inferring phylogenies. The representation is natural and unique based on the biological distances of proteins in protein space. This will solve the fundamental question of how proteins are distributed in the protein universe. Copyright © 2012 Elsevier Ltd. All rights reserved.

Electrophoresis and spectrometric analyses of adaptation-related proteins in thermally stressed Chromobacterium violaceum.

PubMed

Cordeiro, I B; Castro, D P; Nogueira, P P O; Angelo, P C S; Nogueira, P A; Gonçalves, J F C; Pereira, A M R F; Garcia, J S; Souza, G H M F; Arruda, M A Z; Eberlin, M N; Astolfi-Filho, S; Andrade, E V; López-Lozano, J L

2013-10-29

Chromobacterium violaceum is a Gram-negative proteobacteria found in water and soil; it is widely distributed in tropical and subtropical regions, such as the Amazon rainforest. We examined protein expression changes that occur in C. violaceum at different growth temperatures using electrophoresis and mass spectrometry. The total number of spots detected was 1985; the number ranged from 99 to 380 in each assay. The proteins that were identified spectrometrically were categorized as chaperones, proteins expressed exclusively under heat stress, enzymes involved in the respiratory and fermentation cycles, ribosomal proteins, and proteins related to transport and secretion. Controlling inverted repeat of chaperone expression and inverted repeat DNA binding sequences, as well as regions recognized by sigma factor 32, elements involved in the genetic regulation of the bacterial stress response, were identified in the promoter regions of several of the genes coding proteins, involved in the C. violaceum stress response. We found that 30 °C is the optimal growth temperature for C. violaceum, whereas 25, 35, and 40 °C are stressful temperatures that trigger the expression of chaperones, superoxide dismutase, a probable small heat shock protein, a probable phasing, ferrichrome-iron receptor protein, elongation factor P, and an ornithine carbamoyltransferase catabolite. This information improves our comprehension of the mechanisms involved in stress adaptation by C. violaceum.

Relationships between stress, coping and depressive symptoms among overseas university preparatory Chinese students: a cross-sectional study

PubMed Central

2011-01-01

Background Mental health problems in young people are an important public health issue. Students leaving their hometown and family at a young age to pursue better educational opportunities overseas are confronted with life adjustment stress, which in turn affects their mental health and academic performance. This study aimed to examine the relationships among stress, coping strategies, and depressive symptoms using the stress coping framework in overseas Chinese university preparatory students in Taiwan. Methods A cross-sectional study was conducted at an overseas Chinese university preparatory institute in Taiwan. Of enrolled overseas Chinese university preparatory students at 2009, 756 completed a structured questionnaire measuring stress, strategies for coping with it, and the Center for Epidemiologic Studies Depression Scale. Results High levels of stress significantly predicted the adoption of active, problem-focused coping strategies (R2 = 0.13, p < .01) and passive, emotion-focused coping strategies (R2 = 0.24, p < .01). Acceptable CFI, SRMR, and RMSEA values from the structural equation modeling analysis demonstrated that the model satisfactorily fits the stress coping framework, after active coping strategies were eliminated from the model. Results from the Sobel test revealed that passive coping strategies mediated the relation between stress and depressive symptoms (z = 8.06, p < .001). Conclusion Our study results suggested that stress is associated with coping strategies and depressive symptoms and passive strategies mediate the relation between stress and depressive symptoms in overseas Chinese university preparatory students. PMID:21595974

The Zinc-Finger Thylakoid-Membrane Protein FIP Is Involved With Abiotic Stress Response in Arabidopsis thaliana.

PubMed

Lopes, Karina L; Rodrigues, Ricardo A O; Silva, Marcos C; Braga, Wiliane G S; Silva-Filho, Marcio C

2018-01-01

Many plant genes have their expression modulated by stress conditions. Here, we used Arabidopsis FtsH5 protease, which expression is regulated by light stress, as bait in a yeast two-hybrid screen to search for new proteins involved in the stress response. As a result, we found FIP (FtsH5 Interacting Protein), which possesses an amino proximal cleavable transit peptide, a hydrophobic membrane-anchoring region, and a carboxyl proximal C 4 -type zinc-finger domain. In vivo experiments using FIP fused to green fluorescent protein (GFP) showed a plastid localization. This finding was corroborated by chloroplast import assays that showed FIP inserted in the thylakoid membrane. FIP expression was down-regulated in plants exposed to high light intensity, oxidative, salt, and osmotic stresses, whereas mutant plants expressing low levels of FIP were more tolerant to these abiotic stresses. Our data shows a new thylakoid-membrane protein involved with abiotic stress response in Arabidopsis thaliana .

ER stress-induced protein, VIGG, disturbs plant cation homeostasis, which is correlated with growth retardation and robustness to ER stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katoh, Hironori; Fujita, Keiko; Takuhara, Yuki

2011-02-18

Highlights: {yields} VIGG is an ER stress-induced protein in plant. {yields} We examine the characteristics of VIGG-overexpressing Arabidopsis plants. {yields} VIGG-overexpressing plants reveal growth retardation and robustness to ER stress. {yields} VIGG disturbs cation homeostasis in plant. -- Abstract: VIGG is a putative endoplasmic reticulum (ER) resident protein induced by virus infection and ER stress, and is correlated with fruit quality in grapevine. The present study was undertaken to determine the biological function of VIGG in grapevine. Experiments using fluorescent protein-VIGG fusion protein demonstrated that VIGG is localized in ER and the ER targeting sequence is in the N-terminus. Themore » overexpression of VIGG in Arabidopsis plant led to growth retardation. The rosette leaves of VIGG-overexpressing plants were smaller than those of the control plants and rolled at 42 days after seeding. VIGG-overexpressing plants revealed robustness to ER stress as well as the low expression of ER stress marker proteins, such as the luminal binding proteins. These characteristics of VIGG-overexpressing plants were supported by a microarray experiment that demonstrated the disruption of genes related to ER stress response and flowering, as well as cation mobility, in the plants. Finally, cation homeostasis in the plants was disturbed by the overexpression of VIGG. Taken together, these results suggest that VIGG may disturb cation homeostasis in plant, which is correlated with the robustness to ER stress and growth retardation.« less

Protein intake and stress levels in nurses and housewives of Pakistan

PubMed Central

Wattoo, Feroza Hamid; Memon, Muhammad Saleh; Memon, Allah Nawaz; Wattoo, Muhammad Hamid Sarwar; Asad, Muhammad Javaid; Siddique, Farzana

2011-01-01

Stress has many biological effects on human daily life. In the present study, dietary protein intake was correlated with the investigated stress levels of nurses and housewives of the targeted urban population. Age group ranged from 30 to 45 years and both the groups belonged to middle socioeconomic status. After calculations of environmental, psychological and physiological stresses, it was observed that the levels of stress in housewives were significantly higher than those of nurses. Recommended dietary allowances, RDA and actual protein intakes, API were also compared in both the groups. The found protein intake was less in housewives as compared to that of nurses. PMID:23961140

Protein intake and stress levels in nurses and housewives of Pakistan.

PubMed

Wattoo, Feroza Hamid; Memon, Muhammad Saleh; Memon, Allah Nawaz; Wattoo, Muhammad Hamid Sarwar; Asad, Muhammad Javaid; Siddique, Farzana

2011-07-01

Stress has many biological effects on human daily life. In the present study, dietary protein intake was correlated with the investigated stress levels of nurses and housewives of the targeted urban population. Age group ranged from 30 to 45 years and both the groups belonged to middle socioeconomic status. After calculations of environmental, psychological and physiological stresses, it was observed that the levels of stress in housewives were significantly higher than those of nurses. Recommended dietary allowances, RDA and actual protein intakes, API were also compared in both the groups. The found protein intake was less in housewives as compared to that of nurses.

Proteomic analysis of common bean stem under drought stress using in-gel stable isotope labeling.

PubMed

Zadražnik, Tanja; Egge-Jacobsen, Wolfgang; Meglič, Vladimir; Šuštar-Vozlič, Jelka

2017-02-01

Drought is an abiotic stress that strongly influences plant growth, development and productivity. Proteome changes in the stem of the drought-tolerant common bean (Phaseolus vulgaris L.) cultivar Tiber have were when the plants were exposed to drought. Five-week-old plants were subjected to water deficit by withholding irrigation for 7, 12 and 17days, whereas control plants were regularly irrigated. Relative water content (RWC) of leaves, as an indicator of the degree of cell and tissue hydration, showed the highest statistically significant differences between control and drought-stressed plants after 17days of treatment, where RWC remained at 90% for control and declined to 45% for stressed plants. Plants exposed to drought for 17days and control plants at the same developmental stage were included in quantitative proteomic analysis using in-gel stable isotope labeling of proteins in combination with mass spectrometry. The quantified proteins were grouped into several functional groups, mainly into energy metabolism, photosynthesis, proteolysis, protein synthesis and proteins related to defense and stress. 70kDa heat shock protein showed the greatest increase in abundance under drought of all the proteins, suggesting its role in protecting plants against stress by re-establishing normal protein conformations and thus cellular homeostasis. The abundance of proteins involved in protein synthesis also increased under drought stress, important for recovery of damaged proteins involved in the plant cell's metabolic activities. Other important proteins in this study were related to proteolysis and folding, which are necessary for maintaining proper cellular protein homeostasis. Taken together, these results reveal the complexity of pathways involved in the drought stress response in common bean stems and enable comparison with the results of proteomic analysis of leaves, thus providing important information to further understand the biochemical and molecular mechanisms of drought response in this important legume. Copyright © 2016 Elsevier GmbH. All rights reserved.

Proteome Analysis of Date Palm (Phoenix dactylifera L.) under Severe Drought and Salt Stress.

PubMed

El Rabey, Haddad A; Al-Malki, Abdulrahman L; Abulnaja, Khalid O

2016-01-01

Date palm cultivars differently tolerate salinity and drought stress. This study was carried out to study the response of date palm to severe salinity and drought based on leaf proteome analysis. Eighteen-month-old date palm plants were subjected to severe salt (48 g/L NaCl) and drought (82.5 g/L PEG or no irrigation) conditions for one month. Using a protein 2D electrophoresis method, 55 protein spots were analyzed using mass spectrometry. ATP synthase CF1 alpha chains were significantly upregulated under all three stress conditions. Changes in the abundance of RubisCO activase and one of the RubisCO fragments were significant in the same spots only for salt stress and drought stress with no irrigation, and oxygen-evolving enhancer protein 2 was changed in different spots. Transketolase was significantly changed only in drought stress with PEG. The expression of salt and drought stress genes of the chosen protein spots was either overexpressed or downexpressed as revealed by the high or low protein abundance, respectively. In addition, all drought tolerance genes due to no irrigation were downregulated. In conclusion, the proteome analysis of date palm under salinity and drought conditions indicated that both salinity and drought tolerance genes were differentially expressed resulting in high or low protein abundance of the chosen protein spots as a result of exposure to drought and salinity stress condition.

The Buffer Effect of Therapy Dog Exposure on Stress Reactivity in Undergraduate Students

PubMed Central

Fiocco, Alexandra J.; Hunse, Anastasia M.

2017-01-01

Stress is an insidious health risk that is commonly reported among university students. While research suggests that dog exposure may facilitate recovery from a stress response, little is known about the buffer effect of dog exposure on the stress response to a future stressor. This study examined whether interaction with a therapy dog could reduce the strength of the physiological stress response when exposed to a subsequent stressor. Sixty-one university students were randomly assigned to either a therapy dog (TD, n = 31) or a no-dog control (C, n = 30) group. The stress response was measured by electrodermal activity (EDA) in response to the Paced Auditory Serial Addition Test (PASAT). Participants also completed questionnaires that assessed pet attitude, general stress levels, and affect. Analyses of covariance (ANCOVAs) showed that increase in EDA was significantly more pronounced in the C group than in the TD group (p < 0.01). Pet attitudes did not modulate the buffer effect of therapy dog exposure. Results suggest that therapy dog exposure may buffer the stress response in university students, which has implications for the promotion of a viable stress management program on university campuses. PMID:28665340

Molecular Insights into SIRT1 Protection Against UVB-Induced Skin Fibroblast Senescence by Suppression of Oxidative Stress and p53 Acetylation.

PubMed

Chung, Ki Wung; Choi, Yeon Ja; Park, Min Hi; Jang, Eun Ji; Kim, Dae Hyun; Park, Byung Hyun; Yu, Byung Pal; Chung, Hae Young

2015-08-01

Stresses, such as exposure to ultraviolet radiation and those associated with aging, are known to cause premature cellular senescence that is characterized by growth arrest and morphological and gene expression changes. This study was designed to investigate the protective effect of Sirtuin1 (SIRT1) on the UVB-induced premature senescence. Under in vitro experimental conditions, exposure to a subcytotoxic dose of UVB enhanced human skin fibroblasts senescence, as characterized by increased β-galactosidase activity and increased levels of senescence-associated proteins. However, adenovirus-mediated SIRT1 overexpression significantly protected fibroblasts from UVB-induced cellular deterioration. Exposure to UVB-induced cell senescence was associated with oxidative stress and p38 mitogen-activated protein kinase activation. Molecular analysis demonstrated that deacetylation of Forkhead box O3α (FOXO3α) by SIRT1 changed the transcriptional activity of FOXO3α and increased resistance to the oxidative stress. In addition, SIRT1 suppressed UVB-induced p53 acetylation and its transcriptional activity, which directly affected the cell cycle arrest induced by UVB. Further study demonstrated that SIRT1 activation inhibited cell senescence in the skin of the HR1 hairless mouse exposed to UVB. The study identifies a new role for SIRT1 in the UVB-induced senescence of skin fibroblats and provides a potential target for skin protection through molecuar insights into the mechanisms responsible for UVB-induced photoaging. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The influence of academic examinations on energy and nutrient intake in male university students.

PubMed

Barker, Margo E; Blain, Richard J; Russell, Jean M

2015-09-25

Taking examinations is central to student experience at University and may cause psychological stress. Although stress is recognised to impact on food intake, the effects of undertaking examinations on students' dietary intake have not been well characterised. The purpose of this study was to assess how students' energy and nutrient intake may alter during examination periods. The study design was a within-subject comparison of students' energy and nutrient intake during an examination period contrasted with that outside an examination period (baseline). A total of 20 male students from the University of Sheffield completed an automated photographic 4-d dietary record alongside four 24-h recalls in each time period. Daily energy and nutrient intake was estimated for each student by time period and change in energy and nutrient intake calculated. Intakes at baseline were compared to UK dietary recommendations. Cluster analysis categorised students according to their change in energy intake between baseline and the examination period. Non-parametric statistical tests identified differences by cluster. Baseline intakes did not meet recommendations for energy, non-milk extrinsic sugars, non-starch polysaccharide and sodium. Three defined clusters of students were identified: Cluster D who decreased daily energy intake by 12.06 MJ (n = 5), Cluster S who had similar energy intakes (n = 13) and Cluster I who substantially increased energy intake by 6.37 MJ (n = 2) between baseline and examination period. There were statistically significant differences (all p < 0.05) in change in intake of protein, carbohydrate, calcium and sodium between clusters. Cluster D recorded greater energy, carbohydrate and protein intakes than Cluster I at baseline. The majority of students were dietary resilient. Students who demonstrated hypophagia in the examination period had a high energy and nutrient intake at baseline, conversely those who showed hyperphagia had a low energy and nutrient intake. These patterns require confirmation in studies including women, but if confirmed, there is need to address some students' poor food choice especially during examinations.

The effects of glutathione depletion on thermotolerance and heat stress protein synthesis.

PubMed Central

Russo, A.; Mitchell, J. B.; McPherson, S.

1984-01-01

The effects of cellular glutathione depletion by buthionine sulfoximine on the development of thermotolerance and synthesis of heat stress protein was studied. Cellular glutathione levels were found to increase rapidly following an acute heat treatment of either 12 min at 45.5 degrees C or 1 h at 43 degrees C and remain elevated for prolonged periods. Glutathione depletion and prevention of glutathione synthesis by buthionine sulfoximine resulted in inhibition of the development of thermotolerance and a decrease in total protein as well as specific heat stress proteins. While the degree of inhibition of thermotolerance was similar for both glutathione depletion protocols, inhibition in heat stress protein synthesis was greater when glutathione was depleted to low levels prior to heating. The possible role of glutathione and the cellular redox state to thermotolerance and synthesis of heat stress protein is discussed. Images Figure 2 PMID:6733022

Drought and salinity induced changes in ecophysiology and proteomic profile of Parthenium hysterophorus.

PubMed

Ahmad, Javed; Bashir, Humayra; Bagheri, Rita; Baig, Affan; Al-Huqail, Asma; Ibrahim, Mohamed M; Qureshi, M Irfan

2017-01-01

Parthenium hysterophorus is a plant that tolerates drought and salinity to an extremely high degree. Higher expression of stress-responsive proteome contributes for greater defence against abiotic stresses. Thus, P. hysterophorus could be a rich source of genes that encode stress-imparting mechanisms and systems. The present study utilizes comparative physiological and proteomic approaches for identification of key proteins involved in stress-defence of P. hysterophorus. Thirty-days-old plants were exposed to drought (10% PEG 6000) and salinity (160 mM NaCl) for 10 days duration. Both stresses induced oxidative stress estimated in terms of TBARS and H2O2. Levels of both enzymatic and non-enzymatic antioxidants were elevated, more by drought than salinity. Particularly, SOD, GR, CAT and GST proved to be assisting as very commendable defence under drought, as well as salinity. Levels of ascorbate, glutathione and proline were also increased by both stresses, more in response to drought. Comparative proteomics analysis revealed a significant change in relative abundance of 72 proteins under drought and salinity. Drought and salinity increased abundance of 45 and 41 proteins and decreased abundance of 24 and 26 proteins, respectively. Drought and salinity increased and decreased abundance of 31 and 18 proteins, respectively. The functions of identified proteins included those related to defence response (26%), signal transduction (13%), transcription and translation (10%), growth and development (8.5%), photosynthesis (8.5%), metabolism (7%), terpenoid biosynthesis (5.5%), protein modification and transport (7%), oxido-reductase (4%) and Miscellaneous (11%). Among the defence related proteins, antioxidants and HSPs constituted 26% and 21%, respectively. Present study suggests a potential role of defence proteins. Proteins involved in molecular stabilization, formation of osmolytes and wax and contributing to stress-avoiding anatomical features emerged as key and complex mechanisms for imparting stress tolerance to P. hysterophorus.

Drought and salinity induced changes in ecophysiology and proteomic profile of Parthenium hysterophorus

PubMed Central

Ahmad, Javed; Bashir, Humayra; Bagheri, Rita; Baig, Affan; Al-Huqail, Asma; Ibrahim, Mohamed M.

2017-01-01

Parthenium hysterophorus is a plant that tolerates drought and salinity to an extremely high degree. Higher expression of stress-responsive proteome contributes for greater defence against abiotic stresses. Thus, P. hysterophorus could be a rich source of genes that encode stress-imparting mechanisms and systems. The present study utilizes comparative physiological and proteomic approaches for identification of key proteins involved in stress-defence of P. hysterophorus. Thirty-days-old plants were exposed to drought (10% PEG 6000) and salinity (160 mM NaCl) for 10 days duration. Both stresses induced oxidative stress estimated in terms of TBARS and H2O2. Levels of both enzymatic and non-enzymatic antioxidants were elevated, more by drought than salinity. Particularly, SOD, GR, CAT and GST proved to be assisting as very commendable defence under drought, as well as salinity. Levels of ascorbate, glutathione and proline were also increased by both stresses, more in response to drought. Comparative proteomics analysis revealed a significant change in relative abundance of 72 proteins under drought and salinity. Drought and salinity increased abundance of 45 and 41 proteins and decreased abundance of 24 and 26 proteins, respectively. Drought and salinity increased and decreased abundance of 31 and 18 proteins, respectively. The functions of identified proteins included those related to defence response (26%), signal transduction (13%), transcription and translation (10%), growth and development (8.5%), photosynthesis (8.5%), metabolism (7%), terpenoid biosynthesis (5.5%), protein modification and transport (7%), oxido-reductase (4%) and Miscellaneous (11%). Among the defence related proteins, antioxidants and HSPs constituted 26% and 21%, respectively. Present study suggests a potential role of defence proteins. Proteins involved in molecular stabilization, formation of osmolytes and wax and contributing to stress-avoiding anatomical features emerged as key and complex mechanisms for imparting stress tolerance to P. hysterophorus. PMID:28953916

Palmitate-induced ER stress and inhibition of protein synthesis in cultured myotubes does not require Toll-like receptor 4.

PubMed

Perry, Ben D; Rahnert, Jill A; Xie, Yang; Zheng, Bin; Woodworth-Hobbs, Myra E; Price, S Russ

2018-01-01

Saturated fatty acids, such as palmitate, are elevated in metabolically dysfunctional conditions like type 2 diabetes mellitus. Palmitate has been shown to impair insulin sensitivity and suppress protein synthesis while upregulating proteolytic systems in skeletal muscle. Increased sarco/endoplasmic reticulum (ER) stress and subsequent activation of the unfolded protein response may contribute to the palmitate-induced impairment of muscle protein synthesis. In some cell types, ER stress occurs through activation of the Toll-like receptor 4 (TLR4). Given the link between ER stress and suppression of protein synthesis, we investigated whether palmitate induces markers of ER stress and protein synthesis by activating TLR4 in cultured mouse C2C12 myotubes. Myotubes were treated with vehicle, a TLR4-specific ligand (lipopolysaccharides), palmitate, or a combination of palmitate plus a TLR4-specific inhibitor (TAK-242). Inflammatory indicators of TLR4 activation (IL-6 and TNFα) and markers of ER stress were measured, and protein synthesis was assessed using puromycin incorporation. Palmitate substantially increased the levels of IL-6, TNF-α, CHOP, XBP1s, and ATF 4 mRNAs and augmented the levels of CHOP, XBP1s, phospho-PERK and phospho-eIF2α proteins. The TLR4 antagonist attenuated both acute palmitate and LPS-induced increases in IL-6 and TNFα, but did not reduce ER stress signaling with either 6 h or 24 h palmitate treatment. Similarly, treating myotubes with palmitate for 6 h caused a 43% decline in protein synthesis consistent with an increase in phospho-eIF2α, and the TLR4 antagonist did not alter these responses. These results suggest that palmitate does not induce ER stress through TLR4 in muscle, and that palmitate impairs protein synthesis in skeletal muscle in part by induction of ER stress.

NELL2 function in the protection of cells against endoplasmic reticulum stress.

PubMed

Kim, Dong Yeol; Kim, Han Rae; Kim, Kwang Kon; Park, Jeong Woo; Lee, Byung Ju

2015-01-01

Continuous intra- and extracellular stresses induce disorder of Ca(2+) homeostasis and accumulation of unfolded protein in the endoplasmic reticulum (ER), which results in ER stress. Severe long-term ER stress triggers apoptosis signaling pathways, resulting in cell death. Neural epidermal growth factor-like like protein 2 (NELL2) has been reported to be important in protection of cells from cell death-inducing environments. In this study, we investigated the cytoprotective effect of NELL2 in the context of ER stress induced by thapsigargin, a strong ER stress inducer, in Cos7 cells. Overexpression of NELL2 prevented ER stress-mediated apoptosis by decreasing expression of ER stress-induced C/EBP homologous protein (CHOP) and increasing ER chaperones. In this context, expression of anti-apoptotic Bcl-xL was increased by NELL2, whereas NELL2 decreased expression of pro-apoptotic proteins, such as cleaved caspases 3 and 7. This anti-apoptotic effect of NELL2 is likely mediated by extracellular signal-regulated kinase (ERK) signaling, because its inhibitor, U0126, inhibited effects of NELL2 on the expression of anti- and pro-apoptotic proteins and on the protection from ER stress-induced cell death.

Effects of the Bacterial Extract OM-85 on Phagocyte Functions and the Stress Response

PubMed Central

Baladi, S.; Kantengwa, S.; Donati, Y. R. A.; Polla, B. S.

1994-01-01

The effects of the bacterial extract OM-85 on the respiratory burst, intracellular calcium and the stress response have been investigated in human peripheral blood monocytes from normal donors. Activation of the respiratory burst during bacterial phagocytosis has been previously associated with heat shock/stress proteins synthesis. Whereas OM-85 stimulated superoxide production and increased Ca2+ mobilization, it fared to induce synthesis of classical HSPs. The lack of stress protein induction was observed even in the presence of iron which potentiates both oxidative injury and stress protein induction during bacterial phagocytosis. However OM-85 induced a 75–78 kDa protein, which is likely to be a glucose regulated protein (GRP78), and enhanced intracellular expression of interleukin-lβ precursor. PMID:18472933

Membrane Stored Curvature Elastic Stress Modulates Recruitment of Maintenance Proteins PspA and Vipp1.

PubMed

McDonald, Christopher; Jovanovic, Goran; Ces, Oscar; Buck, Martin

2015-09-01

Phage shock protein A (PspA), which is responsible for maintaining inner membrane integrity under stress in enterobacteria, and vesicle-inducting protein in plastids 1 (Vipp1), which functions for membrane maintenance and thylakoid biogenesis in cyanobacteria and plants, are similar peripheral membrane-binding proteins. Their homologous N-terminal amphipathic helices are required for membrane binding; however, the membrane features recognized and required for expressing their functionalities have remained largely uncharacterized. Rigorously controlled, in vitro methodologies with lipid vesicles and purified proteins were used in this study and provided the first biochemical and biophysical characterizations of membrane binding by PspA and Vipp1. Both proteins are found to sense stored curvature elastic (SCE) stress and anionic lipids within the membrane. PspA has an enhanced sensitivity for SCE stress and a higher affinity for the membrane than Vipp1. These variations in binding may be crucial for some of the proteins' differing roles in vivo. Assays probing the transcriptional regulatory function of PspA in the presence of vesicles showed that a relief of transcription inhibition occurs in an SCE stress-specific manner. This in vitro recapitulation of membrane stress-dependent transcription control suggests that the Psp response may be mounted in vivo when a cell's inner membrane experiences increased SCE stress. All cell types maintain the integrity of their membrane systems. One widely distributed membrane stress response system in bacteria is the phage shock protein (Psp) system. The central component, peripheral membrane protein PspA, which mitigates inner membrane stress in bacteria, has a counterpart, Vipp1, which functions for membrane maintenance and thylakoid biogenesis in plants and photosynthetic bacteria. Membrane association of both these proteins is accepted as playing a pivotal role in their functions. Here we show that direct membrane binding by PspA and Vipp1 is driven by two physio-chemical signals, one of which is membrane stress specific. Our work points to alleviation of membrane stored curvature elastic stress by amphipathic helix insertions as an attractive mechanism for membrane maintenance by PspA and Vipp1. Furthermore, the identification of a physical, stress-related membrane signal suggests a unilateral mechanism that promotes both binding of PspA and induction of the Psp response. Copyright © 2015 McDonald et al.

Polyethylene glycol rinse solution: An effective way to prevent ischemia-reperfusion injury

PubMed Central

Zaouali, Mohamed Amine; Bejaoui, Mohamed; Calvo, Maria; Folch-Puy, Emma; Pantazi, Eirini; Pasut, Gianfranco; Rimola, Antoni; Ben Abdennebi, Hassen; Adam, René; Roselló-Catafau, Joan

2014-01-01

AIM: To test whether a new rinse solution containing polyethylene glycol 35 (PEG-35) could prevent ischemia-reperfusion injury (IRI) in liver grafts. METHODS: Sprague-Dawley rat livers were stored in University of Wisconsin preservation solution and then washed with different rinse solutions (Ringer’s lactate solution and a new rinse solution enriched with PEG-35 at either 1 or 5 g/L) before ex vivo perfusion with Krebs-Heinseleit buffer solution. We assessed the following: liver injury (transaminase levels), mitochondrial damage (glutamate dehydrogenase activity), liver function (bile output and vascular resistance), oxidative stress (malondialdehyde), nitric oxide, liver autophagy (Beclin-1 and LCB3) and cytoskeleton integrity (filament and globular actin fraction); as well as levels of metalloproteinases (MMP2 and MMP9), adenosine monophosphate-activated protein kinase (AMPK), heat shock protein 70 (HSP70) and heme oxygenase 1 (HO-1). RESULTS: When we used the PEG-35 rinse solution, reduced hepatic injury and improved liver function were noted after reperfusion. The PEG-35 rinse solution prevented oxidative stress, mitochondrial damage, and liver autophagy. Further, it increased the expression of cytoprotective heat shock proteins such as HO-1 and HSP70, activated AMPK, and contributed to the restoration of cytoskeleton integrity after IRI. CONCLUSION: Using the rinse solution containing PEG-35 was effective for decreasing liver graft vulnerability to IRI. PMID:25473175

Melatonin enhances thermotolerance by promoting cellular protein protection in tomato plants.

PubMed

Xu, Wen; Cai, Shu-Yu; Zhang, Yun; Wang, Yu; Ahammed, Golam Jalal; Xia, Xiao-Jian; Shi, Kai; Zhou, Yan-Hong; Yu, Jing-Quan; Reiter, Russel J; Zhou, Jie

2016-11-01

Melatonin is a pleiotropic signaling molecule that provides physiological protection against diverse environmental stresses in plants. Nonetheless, the mechanisms for melatonin-mediated thermotolerance remain largely unknown. Here, we report that endogenous melatonin levels increased with a rise in ambient temperature and that peaked at 40°C. Foliar pretreatment with an optimal dose of melatonin (10 μmol/L) or the overexpression of N-acetylserotonin methyltransferase (ASMT) gene effectively ameliorated heat-induced photoinhibition and electrolyte leakage in tomato plants. Both exogenous melatonin treatment and endogenous melatonin manipulation by overexpression of ASMT decreased the levels of insoluble and ubiquitinated proteins, but enhanced the expression of heat-shock proteins (HSPs) to refold denatured and unfolded proteins under heat stress. Meanwhile, melatonin also induced expression of several ATG genes and formation of autophagosomes to degrade aggregated proteins under the same stress. Proteomic profile analyses revealed that protein aggregates for a large number of biological processes accumulated in wild-type plants. However, exogenous melatonin treatment or overexpression of ASMT reduced the accumulation of aggregated proteins. Aggregation responsive proteins such as HSP70 and Rubisco activase were preferentially accumulated and ubiquitinated in wild-type plants under heat stress, while melatonin mitigated heat stress-induced accumulation and ubiquitination of aggregated proteins. These results suggest that melatonin promotes cellular protein protection through induction of HSPs and autophagy to refold or degrade denatured proteins under heat stress in tomato plants. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Endoplasmic reticulum stress mediates withaferin A-induced apoptosis in human renal carcinoma cells.

PubMed

Choi, Min Jung; Park, Eun Jung; Min, Kyoung Jin; Park, Jong-Wook; Kwon, Taeg Kyu

2011-04-01

The accumulation of misfolded proteins in the lumen of the endoplasmic reticulum (ER) results in cellular stress that initiates a specialized response designated as the unfolded protein response. ER stress has been implicated in a variety of common diseases, such as diabetes, ischemia and neurodegenerative disorders. Withaferin A, a major chemical constituent of Withania somnifera, has been reported to inhibit tumor cell growth. We show that withaferin A induced a dose-dependent apoptotic cell death in several types of human cancer cells, as measured by FACS analysis and PARP cleavage. Treatment of Caki cells with withaferin A induced a number of signature ER stress markers, including phosphorylation of eukaryotic initiation factor-2α (eIF-2 α), ER stress-specific XBP1 splicing, and up-regulation of glucose-regulated protein (GRP)-78. In addition, withaferin A caused up-regulation of CAAT/enhancer-binding protein-homologous protein (CHOP), suggesting the induction of ER stress. Pretreatment with N-acetyl cysteine (NAC) significantly inhibited withaferin A-mediated ER stress proteins and cell death, suggesting that reactive oxygen species (ROS) mediate withaferin A-induced ER stress. Furthermore, CHOP siRNA or inhibition of caspase-4 activity attenuated withaferin A-induced apoptosis. Taken together, the present study provides strong evidence supporting an important role of the ER stress response in mediating withaferin A-induced apoptosis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Genome-Wide Identification and Comprehensive Expression Profiling of Ribosomal Protein Small Subunit (RPS) Genes and their Comparative Analysis with the Large Subunit (RPL) Genes in Rice

PubMed Central

Saha, Anusree; Das, Shubhajit; Moin, Mazahar; Dutta, Mouboni; Bakshi, Achala; Madhav, M. S.; Kirti, P. B.

2017-01-01

Ribosomal proteins (RPs) are indispensable in ribosome biogenesis and protein synthesis, and play a crucial role in diverse developmental processes. Our previous studies on Ribosomal Protein Large subunit (RPL) genes provided insights into their stress responsive roles in rice. In the present study, we have explored the developmental and stress regulated expression patterns of Ribosomal Protein Small (RPS) subunit genes for their differential expression in a spatiotemporal and stress dependent manner. We have also performed an in silico analysis of gene structure, cis-elements in upstream regulatory regions, protein properties and phylogeny. Expression studies of the 34 RPS genes in 13 different tissues of rice covering major growth and developmental stages revealed that their expression was substantially elevated, mostly in shoots and leaves indicating their possible involvement in the development of vegetative organs. The majority of the RPS genes have manifested significant expression under all abiotic stress treatments with ABA, PEG, NaCl, and H2O2. Infection with important rice pathogens, Xanthomonas oryzae pv. oryzae (Xoo) and Rhizoctonia solani also induced the up-regulation of several of the RPS genes. RPS4, 13a, 18a, and 4a have shown higher transcript levels under all the abiotic stresses, whereas, RPS4 is up-regulated in both the biotic stress treatments. The information obtained from the present investigation would be useful in appreciating the possible stress-regulatory attributes of the genes coding for rice ribosomal small subunit proteins apart from their functions as house-keeping proteins. A detailed functional analysis of independent genes is required to study their roles in stress tolerance and generating stress- tolerant crops. PMID:28966624

Dysregulation of the ADAM17/Notch signalling pathways in endometriosis: from oxidative stress to fibrosis.

PubMed

González-Foruria, Iñaki; Santulli, Pietro; Chouzenoux, Sandrine; Carmona, Francisco; Chapron, Charles; Batteux, Frédéric

2017-07-01

Is oxidative stress associated with the A disintegrin and metalloproteases (ADAM) metallopeptidase domain 17 (ADAM17)/Notch signalling pathway and fibrosis in the development of endometriosis? Oxidative stress is correlated with hyperactivation of the ADAM17/Notch signalling pathway and a consequent increase in fibrosis in patients with endometriosis. It is nowadays accepted that oxidative stress plays an important role in the onset and progression of endometriosis. Oxidative stress is able to induce the synthesis of some members of the 'ADAM' family, such as ADAM17. ADAM17/Notch signalling is dysregulated in other profibrotic and inflammatory diseases. This was a prospective laboratory study conducted in a tertiary-care university hospital between January 2011 and April 2013. We investigated non-pregnant, younger than 42-year-old patients (n = 202) during surgery for a benign gynaecological condition. After complete surgical exploration of the abdominopelvic cavity, 121 women with histologically proven endometriosis and 81 endometriosis-free control women were enrolled. Peritoneal fluid (PF) samples were obtained from all the study participants during surgery in order to detect advanced oxidation protein products (AOPPs) and metalloproteinase activity of ADAM17. Stromal cells from endometrial specimens (n = 8) were obtained from endometrium of control patients (Cs), and from eutopic (Es) and ectopic (Ps) endometrium of patients with deep infiltrating endometriosis (DIE) (n = 8). ADAM17, Notch and the fibrosis markers α-smooth muscle actin (α-SMA) and type-I collagen were assessed using immunoblotting in all the endometrial samples obtained. Additionally, fibrosis was assessed after using Notch cleavage inhibitors (DAPT and FLI-06). Notch and fibrosis were also evaluated after stimulation of stromal endometrial cells with ADAM17 purified protein, increasing concentrations of H2O2 and primary cell culture supernatants. Patients with DIE presented higher PF AOPP and ADAM17 protein levels than controls (P < 0.01 and P < 0.05, respectively). In addition, these two markers were positively correlated (r = 0.614; P < 0.001). At the cellular level, ADAM17 activity was increased in Es and Ps compared to Cs (P < 0.001 and P < 0.01, respectively). Furthermore, Ps presented hyperactivation of Notch signalling (P < 0.05) and augmentation of fibrosis markers (P = 0.009 for α-SMA and P = 0.015 for type-I collagen) compared to controls. The use of DAPT and FLI-06 reduced both fibrosis markers in Ps but not in Cs. Stimulation with ADAM17, H2O2 and Ps supernatant culture significantly increased Notch and fibrosis in both Ps and Cs. N/A. The control group consisted of women who underwent surgery for benign gynaecological conditions, which could lead to biases because some of these conditions may cause alterations in oxidative stress and the ADAM17/Notch pathways. The small sample size of endometrial biopsies used for each group of patients (n = 8) is a limitation of the study, and results should be interpreted with caution. We propose a novel pathway in endometriosis pathogenesis that correlates oxidative stress, hyperactivation of ADAM17/Notch signalling and a consequent increase in fibrosis. This study suggests that Notch signalling plays a key role in the fibrotic processes that take place in ectopic lesions of patients with DIE, as already observed in other pro-fibrotic diseases. This work was supported by grants from University Paris Descartes, INSERM and Fundación Alfonso Martín Escudero. The authors have no competing interests to declare. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Effect of the unfolded protein response on ER protein export: a potential new mechanism to relieve ER stress.

PubMed

Shaheen, Alaa

2018-05-05

The unfolded protein response (UPR) is an adaptive cellular response that aims to relieve endoplasmic reticulum (ER) stress via several mechanisms, including inhibition of protein synthesis and enhancement of protein folding and degradation. There is a controversy over the effect of the UPR on ER protein export. While some investigators suggested that ER export is inhibited during ER stress, others suggested the opposite. In this article, their conflicting studies are analyzed and compared in attempt to solve this controversy. The UPR appears indeed to enhance ER export, possibly via multiple mechanisms. However, another factor, which is the integrity of the folding machinery/environment inside ER, determines whether ER export will appear increased or decreased during experimentation. Also, different methods of stress induction appear to have different effects on ER export. Thus, improvement of ER export may represent a new mechanism by which the UPR alleviates ER stress. This may help researchers to understand how the UPR works inside cells and how to manipulate it to alter cell fate during stress, either to promote cell survival or death. This may open up new approaches for the treatment of ER stress-related diseases.

A Central Role for Thiols in Plant Tolerance to Abiotic Stress

PubMed Central

Zagorchev, Lyuben; Seal, Charlotte E.; Kranner, Ilse; Odjakova, Mariela

2013-01-01

Abiotic stress poses major problems to agriculture and increasing efforts are being made to understand plant stress response and tolerance mechanisms and to develop new tools that underpin successful agriculture. However, the molecular mechanisms of plant stress tolerance are not fully understood, and the data available is incomplete and sometimes contradictory. Here, we review the significance of protein and non-protein thiol compounds in relation to plant tolerance of abiotic stress. First, the roles of the amino acids cysteine and methionine, are discussed, followed by an extensive discussion of the low-molecular-weight tripeptide, thiol glutathione, which plays a central part in plant stress response and oxidative signalling and of glutathione-related enzymes, including those involved in the biosynthesis of non-protein thiol compounds. Special attention is given to the glutathione redox state, to phytochelatins and to the role of glutathione in the regulation of the cell cycle. The protein thiol section focuses on glutaredoxins and thioredoxins, proteins with oxidoreductase activity, which are involved in protein glutathionylation. The review concludes with a brief overview of and future perspectives for the involvement of plant thiols in abiotic stress tolerance. PMID:23549272

Role and regulation of autophagy in heat stress responses of tomato plants

PubMed Central

Zhou, Jie; Wang, Jian; Yu, Jing-Quan; Chen, Zhixiang

2014-01-01

As sessile organisms, plants are constantly exposed to a wide spectrum of stress conditions such as high temperature, which causes protein misfolding. Misfolded proteins are highly toxic and must be efficiently removed to reduce cellular proteotoxic stress if restoration of native conformations is unsuccessful. Although selective autophagy is known to function in protein quality control by targeting degradation of misfolded and potentially toxic proteins, its role and regulation in heat stress responses have not been analyzed in crop plants. In the present study, we found that heat stress induced expression of autophagy-related (ATG) genes and accumulation of autophagosomes in tomato plants. Virus-induced gene silencing (VIGS) of tomato ATG5 and ATG7 genes resulted in increased sensitivity of tomato plants to heat stress based on both increased development of heat stress symptoms and compromised photosynthetic parameters of heat-stressed leaf tissues. Silencing of tomato homologs for the selective autophagy receptor NBR1, which targets ubiquitinated protein aggregates, also compromised tomato heat tolerance. To better understand the regulation of heat-induced autophagy, we found that silencing of tomato ATG5, ATG7, or NBR1 compromised heat-induced expression of not only the targeted genes but also other autophagy-related genes. Furthermore, we identified two tomato genes encoding proteins highly homologous to Arabidopsis WRKY33 transcription factor, which has been previously shown to interact physically with an autophagy protein. Silencing of tomato WRKY33 genes compromised tomato heat tolerance and reduced heat-induced ATG gene expression and autophagosome accumulation. Based on these results, we propose that heat-induced autophagy in tomato is subject to cooperative regulation by both WRKY33 and ATG proteins and plays a critical role in tomato heat tolerance, mostly likely through selective removal of heat-induced protein aggregates. PMID:24817875

Aerobic exercise training rescues cardiac protein quality control and blunts endoplasmic reticulum stress in heart failure rats.

PubMed

Bozi, Luiz H M; Jannig, Paulo R; Rolim, Natale; Voltarelli, Vanessa A; Dourado, Paulo M M; Wisløff, Ulrik; Brum, Patricia C

2016-11-01

Cardiac endoplasmic reticulum (ER) stress through accumulation of misfolded proteins plays a pivotal role in cardiovascular diseases. In an attempt to reestablish ER homoeostasis, the unfolded protein response (UPR) is activated. However, if ER stress persists, sustained UPR activation leads to apoptosis. There is no available therapy for ER stress relief. Considering that aerobic exercise training (AET) attenuates oxidative stress, mitochondrial dysfunction and calcium imbalance, it may be a potential strategy to reestablish cardiac ER homoeostasis. We test the hypothesis that AET would attenuate impaired cardiac ER stress after myocardial infarction (MI). Wistar rats underwent to either MI or sham surgeries. Four weeks later, rats underwent to 8 weeks of moderate-intensity AET. Myocardial infarction rats displayed cardiac dysfunction and lung oedema, suggesting heart failure. Cardiac dysfunction in MI rats was paralleled by increased protein levels of UPR markers (GRP78, DERLIN-1 and CHOP), accumulation of misfolded and polyubiquitinated proteins, and reduced chymotrypsin-like proteasome activity. These results suggest an impaired cardiac protein quality control. Aerobic exercise training improved exercise capacity and cardiac function of MI animals. Interestingly, AET blunted MI-induced ER stress by reducing protein levels of UPR markers, and accumulation of both misfolded and polyubiquinated proteins, which was associated with restored proteasome activity. Taken together, our study provide evidence for AET attenuation of ER stress through the reestablishment of cardiac protein quality control, which contributes to better cardiac function in post-MI heart failure rats. These results reinforce the importance of AET as primary non-pharmacological therapy to cardiovascular disease. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Suppression of grp78 core promoter element-mediated stress induction by the dbpA and dbpB (YB-1) cold shock domain proteins.

PubMed Central

Li, W W; Hsiung, Y; Wong, V; Galvin, K; Zhou, Y; Shi, Y; Lee, A S

1997-01-01

The highly conserved grp78 core promoter element plays an important role in the induction of grp78 under diverse stress signals. Previous studies have established a functional region in the 3' half of the core (stress-inducible change region [SICR]) which exhibits stress-inducible changes in stressed nuclei. The human transcription factor YY1 is shown to bind the SICR and transactivate the core element under stress conditions. Here we report that expression library screening with the core element has identified two new core binding proteins, YB-1 and dbpA. Both proteins belong to the Y-box family of proteins characterized by an evolutionarily conserved DNA binding motif, the cold shock domain (CSD). In contrast to YY1, which binds only double-stranded SICR, the Y-box/CSD proteins much prefer the lower strand of the SICR. The Y-box proteins can repress the inducibility of the grp78 core element mediated by treatment of cells with A23187, thapsigargin, and tunicamycin. In gel shift assays, YY1 binding to the core element is inhibited by either YB-1 or dbpA. A yeast interaction trap screen using LexA-YY1 as a bait and a HeLa cell cDNA-acid patch fusion library identified YB-1 as a YY1-interacting protein. In cotransfection experiments, the Y-box proteins antagonize the YY1-mediated enhancement of transcription directed by the grp78 core in stressed cells. Thus, the CSD proteins may be part of the stress signal transduction mechanism in the mammalian system. PMID:8972186

Edaravone injection reverses learning and memory deficits in a rat model of vascular dementia.

PubMed

Li, Xu; Lu, Fen; Li, Wei; Qin, Lingzhi; Yao, Yong; Ge, Xuerong; Yu, Qingkai; Liang, Xinliang; Zhao, Dongmei; Li, Xiaohong; Zhang, Jiewen

2017-01-01

Edaravone is a novel free radical scavenger that exerts neuroprotective effects by inhibiting endothelial injury and by ameliorating neuronal damage in brain ischemia. Recently, it was reported that edaravone could alleviate the pathology and cognitive deficits of Alzheimer's disease patients. However, its relevance to vascular dementia (VaD) is not clear. In this study, we partially occluded the bilateral carotid arteries of rats surgically to induce chronic cerebral hypoperfusion (CCH), a well-known rat model of VaD. Water maze and step-down inhibitory test were used to evaluate the memory deficit. The activities of superoxide dismutase (SOD) and lactate dehydrogenase (LDH), the content of malondialdehyde (MDA) and total reactive oxygen species were measured to evaluate the oxidative stress level. Western blot analysis was used to evaluate the synaptic protein expression. It was found that treatment with edaravone for a 5-week period was able to reverse both spatial and fear-memory deficits in rats with CCH. Edaravone significantly reduced the level of oxidative stress in the brains of rats with CCH by increasing SOD activity and decreasing the content of MDA, LDH, and total reactive oxygen species. Furthermore, edaravone treatment also restored the levels of multiple synaptic proteins in the hippocampi of rats with CCH. Our data provide direct evidence supporting the neuroprotective effects of edaravone in VaD. We propose that the alleviation of oxidative stress and restoration of synaptic proteins play important roles in neuroprotection. © The Author 2016. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Comparative analysis of soybean plasma membrane proteins under osmotic stress using gel-based and LC MS/MS-based proteomics approaches.

PubMed

Nouri, Mohammad-Zaman; Komatsu, Setsuko

2010-05-01

To study the soybean plasma membrane proteome under osmotic stress, two methods were used: a gel-based and a LC MS/MS-based proteomics method. Two-day-old seedlings were subjected to 10% PEG for 2 days. Plasma membranes were purified from seedlings using a two-phase partitioning method and their purity was verified by measuring ATPase activity. Using the gel-based proteomics, four and eight protein spots were identified as up- and downregulated, respectively, whereas in the nanoLC MS/MS approach, 11 and 75 proteins were identified as up- and downregulated, respectively, under PEG treatment. Out of osmotic stress responsive proteins, most of the transporter proteins and all proteins with high number of transmembrane helices as well as low-abundance proteins could be identified by the LC MS/MS-based method. Three homologues of plasma membrane H(+)-ATPase, which are transporter proteins involved in ion efflux, were upregulated under osmotic stress. Gene expression of this protein was increased after 12 h of stress exposure. Among the identified proteins, seven proteins were mutual in two proteomics techniques, in which calnexin was the highly upregulated protein. Accumulation of calnexin in plasma membrane was confirmed by immunoblot analysis. These results suggest that under hyperosmotic conditions, calnexin accumulates in the plasma membrane and ion efflux accelerates by upregulation of plasma membrane H(+)-ATPase protein.

Stress-Induced Protein S-Glutathionylation and S-Trypanothionylation in African Trypanosomes—A Quantitative Redox Proteome and Thiol Analysis

PubMed Central

Ulrich, Kathrin; Finkenzeller, Caroline; Merker, Sabine; Rojas, Federico; Matthews, Keith; Ruppert, Thomas

2017-01-01

Abstract Aims: Trypanosomatids have a unique trypanothione-based thiol redox metabolism. The parasite-specific dithiol is synthesized from glutathione and spermidine, with glutathionylspermidine as intermediate catalyzed by trypanothione synthetase. In this study, we address the oxidative stress response of African trypanosomes with special focus on putative protein S-thiolation. Results: Challenging bloodstream Trypanosoma brucei with diamide, H2O2 or hypochlorite results in distinct levels of reversible overall protein S-thiolation. Quantitative proteome analyses reveal 84 proteins oxidized in diamide-stressed parasites. Fourteen of them, including several essential thiol redox proteins and chaperones, are also enriched when glutathione/glutaredoxin serves as a reducing system indicating S-thiolation. In parasites exposed to H2O2, other sets of proteins are modified. Only three proteins are S-thiolated under all stress conditions studied in accordance with a highly specific response. H2O2 causes primarily the formation of free disulfides. In contrast, in diamide-treated cells, glutathione, glutathionylspermidine, and trypanothione are almost completely protein bound. Remarkably, the total level of trypanothione is decreased, whereas those of glutathione and glutathionylspermidine are increased, indicating partial hydrolysis of protein-bound trypanothione. Depletion of trypanothione synthetase exclusively induces protein S-glutathionylation. Total mass analyses of a recombinant peroxidase treated with T(SH)2 and either diamide or hydrogen peroxide verify protein S-trypanothionylation as stable modification. Innovation: Our data reveal for the first time that trypanosomes employ protein S-thiolation when exposed to exogenous and endogenous oxidative stresses and trypanothione, despite its dithiol character, forms protein-mixed disulfides. Conclusion: The stress-specific responses shown here emphasize protein S-trypanothionylation and S-glutathionylation as reversible protection mechanism in these parasites. Antioxid. Redox Signal. 27, 517–533. PMID:28338335

Analysis of stress levels among medical students, residents, and graduate students at four Canadian schools of medicine.

PubMed

Toews, J A; Lockyer, J M; Dobson, D J; Simpson, E; Brownell, A K; Brenneis, F; MacPherson, K M; Cohen, G S

1997-11-01

To assess stress in medical students, residents, and graduate science students at four Canadian schools of medicine. Four schools with different curricula in three different parts of Canada participated in the study: the University of Calgary Faculty of Medicine, the University of Alberta Faculty of Medicine, the Dalhousie University Faculty of Medicine, and the McMaster University Faculty of Health Sciences. All the medical students, residents, and graduate science students at each school were surveyed in 1994-95. The three instruments used were the University of Calgary Stress Questionnaire, the Social Readjustment Rating Scale (SRRS), and the Symptom Checklist-90. Demographic data were compared across all four schools. Analysis of variance was calculated for all test-item scores, utilizing a four (school) by three (program) by two (gender) design, which were all between subject factors. Significant main effects were followed up by using planned comparisons (Newman-Keuls, with a probability level of p < .05). Significant interaction effects were followed up by using an analysis of simple effects. A total of 1,681 questionnaires were returned as follows: 621 of 1,304 (48%) from the medical students, 645 of 1,495 (43%) from the residents, and 415 of 829 (50%) from the graduate science students. There were significant differences between the three groups in the natures and degrees of stress, with the graduate students reporting higher levels of stress. There were significant gender differences as well, with the women reporting higher levels of stress. Overall, stress levels were found to be mild, based on the University of Calgary Stress Questionnaire and the SRRS. This study suggests that medical students and residents experience stress at levels that appear acceptable, but ongoing monitoring and the provision of appropriate support systems will continue to be important.

Transcriptomics-based identification of WRKY genes and characterization of a salt and hormone-responsive PgWRKY1 gene in Panax ginseng.

PubMed

Nuruzzaman, Mohammed; Cao, Hongzhe; Xiu, Hao; Luo, Tiao; Li, Jijia; Chen, Xianghui; Luo, Junli; Luo, Zhiyong

2016-02-01

WRKY proteins belong to a transcription factor (TF) family and play dynamic roles in many plant processes, including plant responses to abiotic and biotic stresses, as well as secondary metabolism. However, no WRKY gene in Panax ginseng C.A. Meyer has been reported to date. In this study, a number of WRKY unigenes from methyl jasmonate (MeJA)-treated adventitious root transcriptome of this species were identified using next-generation sequencing technology. A total of 48 promising WRKY unigenes encoding WRKY proteins were obtained by eliminating wrong and incomplete open reading frame (ORF). Phylogenetic analysis reveals 48 WRKY TFs, including 11 Group I, 36 Group II, and 1 Group III. Moreover, one MeJA-responsive unigene designated as PgWRKY1 was cloned and characterized. It contains an entire ORF of 1077 bp and encodes a polypeptide of 358 amino acid residues. The PgWRKY1 protein contains a single WRKY domain consisting of a conserved amino acid sequence motif WRKYGQK and a C2H2-type zinc-finger motif belonging to WRKY subgroup II-d. Subcellular localization of PgWRKY1-GFP fusion protein in onion and tobacco epidermis cells revealed that PgWRKY1 was exclusively present in the nucleus. Quantitative real-time polymerase chain reaction analysis demonstrated that the expression of PgWRKY1 was relatively higher in roots and lateral roots compared with leaves, stems, and seeds. Importantly, PgWRKY1 expression was significantly induced by salicylic acid, abscisic acid, and NaCl, but downregulated by MeJA treatment. These results suggested that PgWRKY1 might be a multiple stress-inducible gene responding to hormones and salt stresses. © The Author 2015. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

Uncovering a Dual Regulatory Role for Caspases During Endoplasmic Reticulum Stress-induced Cell Death

PubMed Central

Anania, Veronica G.; Yu, Kebing; Gnad, Florian; Pferdehirt, Rebecca R.; Li, Han; Ma, Taylur P.; Jeon, Diana; Fortelny, Nikolaus; Forrest, William; Ashkenazi, Avi; Overall, Christopher M.; Lill, Jennie R.

2016-01-01

Many diseases are associated with endoplasmic reticulum (ER) stress, which results from an accumulation of misfolded proteins. This triggers an adaptive response called the “unfolded protein response” (UPR), and prolonged exposure to ER stress leads to cell death. Caspases are reported to play a critical role in ER stress-induced cell death but the underlying mechanisms by which they exert their effect continue to remain elusive. To understand the role caspases play during ER stress, a systems level approach integrating analysis of the transcriptome, proteome, and proteolytic substrate profile was employed. This quantitative analysis revealed transcriptional profiles for most human genes, provided information on protein abundance for 4476 proteins, and identified 445 caspase substrates. Based on these data sets many caspase substrates were shown to be downregulated at the protein level during ER stress suggesting caspase activity inhibits their cellular function. Additionally, RNA sequencing revealed a role for caspases in regulation of ER stress-induced transcriptional pathways and gene set enrichment analysis showed expression of multiple gene targets of essential transcription factors to be upregulated during ER stress upon inhibition of caspases. Furthermore, these transcription factors were degraded in a caspase-dependent manner during ER stress. These results indicate that caspases play a dual role in regulating the cellular response to ER stress through both post-translational and transcriptional regulatory mechanisms. Moreover, this study provides unique insight into progression of the unfolded protein response into cell death, which may help identify therapeutic strategies to treat ER stress-related diseases. PMID:27125827

Uncovering a Dual Regulatory Role for Caspases During Endoplasmic Reticulum Stress-induced Cell Death.

PubMed

Anania, Veronica G; Yu, Kebing; Gnad, Florian; Pferdehirt, Rebecca R; Li, Han; Ma, Taylur P; Jeon, Diana; Fortelny, Nikolaus; Forrest, William; Ashkenazi, Avi; Overall, Christopher M; Lill, Jennie R

2016-07-01

Many diseases are associated with endoplasmic reticulum (ER) stress, which results from an accumulation of misfolded proteins. This triggers an adaptive response called the "unfolded protein response" (UPR), and prolonged exposure to ER stress leads to cell death. Caspases are reported to play a critical role in ER stress-induced cell death but the underlying mechanisms by which they exert their effect continue to remain elusive. To understand the role caspases play during ER stress, a systems level approach integrating analysis of the transcriptome, proteome, and proteolytic substrate profile was employed. This quantitative analysis revealed transcriptional profiles for most human genes, provided information on protein abundance for 4476 proteins, and identified 445 caspase substrates. Based on these data sets many caspase substrates were shown to be downregulated at the protein level during ER stress suggesting caspase activity inhibits their cellular function. Additionally, RNA sequencing revealed a role for caspases in regulation of ER stress-induced transcriptional pathways and gene set enrichment analysis showed expression of multiple gene targets of essential transcription factors to be upregulated during ER stress upon inhibition of caspases. Furthermore, these transcription factors were degraded in a caspase-dependent manner during ER stress. These results indicate that caspases play a dual role in regulating the cellular response to ER stress through both post-translational and transcriptional regulatory mechanisms. Moreover, this study provides unique insight into progression of the unfolded protein response into cell death, which may help identify therapeutic strategies to treat ER stress-related diseases. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Ubiquilin overexpression reduces GFP-polyalanine-induced protein aggregates and toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang Hongmin; Monteiro, Mervyn J.

2007-08-01

Several human disorders are associated with an increase in a continuous stretch of alanine amino acids in proteins. These so-called polyalanine expansion diseases share many similarities with polyglutamine-related disorders, including a length-dependent reiteration of amino acid induction of protein aggregation and cytotoxicity. We previously reported that overexpression of ubiquilin reduces protein aggregates and toxicity of expanded polyglutamine proteins. Here, we demonstrate a similar role for ubiquilin toward expanded polyalanine proteins. Overexpression of ubiquilin-1 in HeLa cells reduced protein aggregates and the cytotoxicity associated with expression of a transfected nuclear-targeted GFP-fusion protein containing 37-alanine repeats (GFP-A37), in a dose dependent manner.more » Ubiquilin coimmunoprecipitated more with GFP proteins containing a 37-polyalanine tract compared to either 7 (GFP-A7), or no alanine tract (GFP). Moreover, overexpression of ubiquilin suppressed the increased vulnerability of HeLa cell lines stably expressing the GFP-A37 fusion protein to oxidative stress-induced cell death compared to cell lines expressing GFP or GFP-A7 proteins. By contrast, siRNA knockdown of ubiquilin expression in the GFP-A37 cell line was associated with decreased cellular proliferation, and increases in GFP protein aggregates, nuclear fragmentation, and cell death. Our results suggest that boosting ubiquilin levels in cells might provide a universal and attractive strategy to prevent toxicity of proteins containing reiterative expansions of amino acids involved in many human diseases.« less

Long-term heat stress induces the inflammatory response in dairy cows revealed by plasma proteome analysis.

PubMed

Min, Li; Zheng, Nan; Zhao, Shengguo; Cheng, Jianbo; Yang, Yongxin; Zhang, Yangdong; Yang, Hongjian; Wang, Jiaqi

2016-03-04

In this work we employed a comparative proteomic approach to evaluate seasonal heat stress and investigate proteomic alterations in plasma of dairy cows. Twelve lactating Holstein dairy cows were used and the treatments were: heat stress (n = 6) in hot summer (at the beginning of the moderate heat stress) and no heat stress (n = 6) in spring natural ambient environment, respectively. Subsequently, heat stress treatment lasted 23 days (at the end of the moderate heat stress) to investigate the alterations of plasma proteins, which might be employed as long-term moderate heat stress response in dairy cows. Changes in plasma proteins were analyzed by two-dimensional electrophoresis (2-DE) combined with mass spectrometry. Analysis of the properties of the identified proteins revealed that the alterations of plasma proteins were related to inflammation in long-term moderate heat stress. Furthermore, the increase in plasma tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) directly demonstrated that long-term moderate heat stress caused an inflammatory response in dairy cows. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparative proteomic analysis of alfalfa revealed new salt and drought stress-related factors involved in seed germination.

PubMed

Ma, Qiaoli; Kang, Junmei; Long, Ruicai; Zhang, Tiejun; Xiong, Junbo; Zhang, Kun; Wang, Tenghua; Yang, Qingchuan; Sun, Yan

2017-07-01

Salinity and drought are two major environmental factors that limit the growth and yield of many forage crops in semi-arid and arid regions. Alfalfa (Medicago sativa L.) is one of the most important forage crops in many countries. We aim to investigate the molecular mechanisms of alfalfa in response to salt and drought stresses in this study. Physiological and proteomic analyses were applied to examine the Zhongmu NO.3 alfalfa seed germination stage with 200 mM NaCl and 180 g·L -1 polyethylene glycol (PEG) treatments. The germination ability of the seed and the accumulation of osmotic solutes were quite different between the NaCl and PEG treatments. More than 800 protein spots were detected by proteomics technology on two-dimensional electrophoresis (2-DE) gels. The abundance of twenty-eight proteins were decreased or increased after salt and drought stress. Seventeen of these proteins were identified and classified into six functional categories through mass spectrometry (MS). The six groups involved in salt- and PEG-mediated stress included defense response, energy metabolism, protein synthesis and degradation, oxidative stress, carbohydrate metabolism-associated proteins, and unknown proteins. We discovered that some proteins related to carbohydrate metabolism and energy production increased in abundance under salt- and PEG-mediated drought stress. This demonstrates a common mechanism of energy consumption during abiotic stresses. Further study of these proteins with unknown function will provide insights into the molecular mechanisms of abiotic stress and the discovery of new candidate markers.

A molecular web: endoplasmic reticulum stress, inflammation, and oxidative stress.

PubMed

Chaudhari, Namrata; Talwar, Priti; Parimisetty, Avinash; Lefebvre d'Hellencourt, Christian; Ravanan, Palaniyandi

2014-01-01

Execution of fundamental cellular functions demands regulated protein folding homeostasis. Endoplasmic reticulum (ER) is an active organelle existing to implement this function by folding and modifying secretory and membrane proteins. Loss of protein folding homeostasis is central to various diseases and budding evidences suggest ER stress as being a major contributor in the development or pathology of a diseased state besides other cellular stresses. The trigger for diseases may be diverse but, inflammation and/or ER stress may be basic mechanisms increasing the severity or complicating the condition of the disease. Chronic ER stress and activation of the unfolded-protein response (UPR) through endogenous or exogenous insults may result in impaired calcium and redox homeostasis, oxidative stress via protein overload thereby also influencing vital mitochondrial functions. Calcium released from the ER augments the production of mitochondrial Reactive Oxygen Species (ROS). Toxic accumulation of ROS within ER and mitochondria disturbs fundamental organelle functions. Sustained ER stress is known to potentially elicit inflammatory responses via UPR pathways. Additionally, ROS generated through inflammation or mitochondrial dysfunction could accelerate ER malfunction. Dysfunctional UPR pathways have been associated with a wide range of diseases including several neurodegenerative diseases, stroke, metabolic disorders, cancer, inflammatory disease, diabetes mellitus, cardiovascular disease, and others. In this review, we have discussed the UPR signaling pathways, and networking between ER stress-induced inflammatory pathways, oxidative stress, and mitochondrial signaling events, which further induce or exacerbate ER stress.

5,7-Dimethoxycoumarin prevents chronic mild stress induced depression in rats through increase in the expression of heat shock protein-70 and inhibition of monoamine oxidase-A levels.

PubMed

Yang, Wei; Wang, Huanlin

2018-02-01

The current study was aimed to investigate the role of 5,7-dimethoxycoumarin in the prevention of chronic mild stress induced depression in rats. The chronic mild stress rat model was prepared using the known protocols. The results from open-field test showed that rats in the chronic mild stress group scored very low in terms of crossings and rearings than those of the normal rats. However, pre-treatment of the rats with 10 mg/kg doses of 5,7-dimethoxycoumarin prevented decline in the locomotor activity by chronic mild stress. The level of monoamine oxidase-A in the chronic mild stress rat hippocampus was markedly higher. Chronic mild stress induced increase in the monoamine oxidase-A level was inhibited by pre-treatment with 10 mg/kg doses of 5,7-dimethoxycoumarin in the rats. Chronic mild stress caused a marked increase in the level of caspase-3 mRNA and proteins in rat hippocampus tissues. The increased level of caspase-3 mRNA and protein level was inhibited by treatment of rats with 5,7-dimethoxycoumarin (10 mg/kg). 5,7-Dimethoxycoumarin administration into the rats caused a marked increase in the levels of heat shock protein-70 mRNA and protein. The levels of heat shock protein-70 were markedly lower both in normal and chronic mild stress groups of rats compared to the 5,7-dimethoxycoumarin treated groups. Thus 5,7-dimethoxycoumarin prevented the chronic mild stress induced depression in rats through an increase in the expression of heat shock protein-70 and inhibition of monoamine oxidase-A levels.

BDNF-GSK-3β-β-Catenin Pathway in the mPFC Is Involved in Antidepressant-Like Effects of Morinda officinalis Oligosaccharides in Rats.

PubMed

Xu, Ling-Zhi; Xu, De-Feng; Han, Ying; Liu, Li-Jing; Sun, Cheng-Yu; Deng, Jia-Hui; Zhang, Ruo-Xi; Yuan, Ming; Zhang, Su-Zhen; Li, Zhi-Meng; Xu, Yi; Li, Jin-Sheng; Xie, Su-Hua; Li, Su-Xia; Zhang, Hong-Yan; Lu, Lin

2017-01-01

Morinda officinalis oligosaccharides have been reported to exert neuroprotective and antidepressant-like effects in the forced swim test in mice. However, the mechanisms that underlie the antidepressant-like effects of Morinda officinalis oligosaccharides are unclear. Chronic unpredictable stress and forced swim test were used to explore the antidepressant-like effects of Morinda officinalis oligosaccharides and resilience to stress in rats. The phosphoinositide-3 kinase inhibitor LY294002 was microinjected in the medial prefrontal cortex to explore the role of glycogen synthase kinase-3β in the antidepressant-like effects of Morinda officinalis oligosaccharides. The expression of brain-derived neurotrophic factor, phosphorylated-Ser9-glycogen synthase kinase 3β, β-catenin, and synaptic proteins was determined in the medial prefrontal cortex and the orbitofrontal cortex by western blot. We found that Morinda officinalis oligosaccharides effectively ameliorated chronic unpredictable stress-induced depression-like behaviors in the sucrose preference test and forced swim test. The Morinda officinalis oligosaccharides also significantly rescued chronic unpredictable stress-induced abnormalities in the brain-derived neurotrophic factor-glycogen synthase kinase-3β-β-catenin pathway and synaptic protein deficits in the medial prefrontal cortex but not orbitofrontal cortex. The activation of glycogen synthase kinase-3β by the phosphoinositide-3 kinase inhibitor LY294002 abolished the antidepressant-like effects of Morinda officinalis oligosaccharides in the forced swim test. Naïve rats that were treated with Morinda officinalis oligosaccharides exhibited resilience to chronic unpredictable stress, accompanied by increases in the expression of brain-derived neurotrophic factor, phosphorylated-Ser9-glycogen synthase kinase-3β, and β-catenin in the medial prefrontal cortex. Our findings indicate that the brain-derived neurotrophic factor-glycogen synthase kinase-3β-β-catenin pathway in the medial prefrontal cortex may underlie the antidepressant-like effect of Morinda officinalis oligosaccharides and resilience to stress. © The Author 2016. Published by Oxford University Press on behalf of CINP.

Comparative shoot proteome analysis of two potato (Solanum tuberosum L.) genotypes contrasting in nitrogen deficiency responses in vitro.

PubMed

Meise, Philipp; Jozefowicz, Anna Maria; Uptmoor, Ralf; Mock, Hans-Peter; Ordon, Frank; Schum, Annegret

2017-08-23

Aiming at a better understanding of the physiological and biochemical background of nitrogen use efficiency, alterations in the shoot proteome under N-deficiency were investigated in two contrasting potato genotypes grown in vitro with 60 and 7.5mM N, respectively. A gel based proteomic approach was applied to identify candidate proteins associated with genotype specific responses to N-deficiency. 21% of the detected proteins differed in abundance between the two genotypes. Between control and N-deficiency conditions 19.5% were differentially accumulated in the sensitive and 15% in the tolerant genotype. 93% of the highly N-deficiency responsive proteins were identified by MALDI TOF/TOF mass spectrometry. The major part was associated with photosynthesis, carbohydrate metabolism, stress response and regulation. Differential accumulation of enzymes involved in the Calvin cycle and glycolysis suggest activation of alternative carbohydrate pathways. In the tolerant genotype, increased abundance under N-deficiency was also found for enzymes involved in chlorophyll synthesis and stability of enzymes, which increase photosynthetic carbon fixation efficiency. Out of a total of 106 differentially abundant proteins, only eight were detected in both genotypes. Our findings suggest that mutually responsive proteins reflect universal stress responses while adaptation to N-deficiency in metabolic pathways is more genotype specific. Nitrogen losses from arable farm land considerably contribute to environmental pollution. In potato, this is a special problem due cultivation on light soils, irrigation and the shallow root system. Therefore, breeding of cultivars with improved nitrogen use efficiency and stable yields under reduced N fertilization is an important issue. Knowledge of genotype dependent adaptation to N-deficiency at the proteome level can help to understand regulation of N efficiency and development of N-efficient cultivars. Copyright © 2017 Elsevier B.V. All rights reserved.

Cell death induced by endoplasmic reticulum stress.

PubMed

Iurlaro, Raffaella; Muñoz-Pinedo, Cristina

2016-07-01

The endoplasmic reticulum is an organelle with multiple functions. The synthesis of transmembrane proteins and proteins that are to be secreted occurs in this organelle. Many conditions that impose stress on cells, including hypoxia, starvation, infections and changes in secretory needs, challenge the folding capacity of the cell and promote endoplasmic reticulum stress. The cellular response involves the activation of sensors that transduce signaling cascades with the aim of restoring homeostasis. This is known as the unfolded protein response, which also intersects with the integrated stress response that reduces protein synthesis through inactivation of the initiation factor eIF2α. Central to the unfolded protein response are the sensors PERK, IRE1 and ATF6, as well as other signaling nodes such as c-Jun N-terminal kinase 1 (JNK) and the downstream transcription factors XBP1, ATF4 and CHOP. These proteins aim to restore homeostasis, but they can also induce cell death, which has been shown to occur by necroptosis and, more commonly, through the regulation of Bcl-2 family proteins (Bim, Noxa and Puma) that leads to mitochondrial apoptosis. In addition, endoplasmic reticulum stress and proteotoxic stress have been shown to induce TRAIL receptors and activation of caspase-8. Endoplasmic reticulum stress is a common feature in the pathology of numerous diseases because it plays a role in neurodegeneration, stroke, cancer, metabolic diseases and inflammation. Understanding how cells react to endoplasmic reticulum stress can accelerate discovery of drugs against these diseases. © 2015 FEBS.

Insect heat shock proteins during stress and diapause.

PubMed

King, Allison M; MacRae, Thomas H

2015-01-07

Insect heat shock proteins include ATP-independent small heat shock proteins and the larger ATP-dependent proteins, Hsp70, Hsp90, and Hsp60. In concert with cochaperones and accessory proteins, heat shock proteins mediate essential activities such as protein folding, localization, and degradation. Heat shock proteins are synthesized constitutively in insects and induced by stressors such as heat, cold, crowding, and anoxia. Synthesis depends on the physiological state of the insect, but the common function of heat shock proteins, often working in networks, is to maintain cell homeostasis through interaction with substrate proteins. Stress-induced expression of heat shock protein genes occurs in a background of protein synthesis inhibition, but in the course of diapause, a state of dormancy and increased stress tolerance, these genes undergo differential regulation without the general disruption of protein production. During diapause, when ATP concentrations are low, heat shock proteins may sequester rather than fold proteins.

Food and mental health: relationship between food and perceived stress and depressive symptoms among university students in the United Kingdom.

PubMed

El Ansari, Walid; Adetunji, Hamed; Oskrochi, Reza

2014-06-01

The current study assessed, by university and sex, the association between nutritional behaviour (twelve independent variables), and stress and depressive symptoms (dependent variables) in a sample from three UK countries. A cross-sectional survey was undertaken among undergraduates enrolled across seven universities in England, Wales and Northern Ireland (N = 3,706). Self-administered questionnaires included a 12-item food frequency questionnaire, Cohen's Perceived Stress Scale and modified Beck Depression Inventory. Sex and university comparisons were undertaken. Univariable and multivariable regression analyses were computed for each of the two outcomes--perceived stress and depressive symptoms. The frequencies of consuming of the various food groups differed by university and sex, as did depressive symptoms and perceived stress. Multivariable regression analyses indicated that consuming 'unhealthy' foods (e.g. sweets, cookies, snacks, fast food) was significantly positively associated with perceived stress (females only) and depressive symptoms (both males and females). Conversely, consuming 'healthy' foods (e.g. fresh fruits, salads, cooked vegetables) was significantly negatively associated with perceived stress and depressive symptoms scores for both sexes. There was significant negative association between consuming fish/sea food and depressive symptoms among males only. For males and for females, consuming lemonade/soft drinks, meat/sausage products, dairy/dairy products, and cereal/cereal products were not associated with either perceived stress or depressive symptoms. The associations between consuming 'unhealthy' foods and higher depressive symptoms and perceived stress among male and female students as well as the associations between consuming 'healthy' foods and lower depressive symptoms and perceived stress among male and female students in three UK countries suggest that interventions to reduce depressive symptoms and stress among students could also result in the consumption of healthier foods and/or vice versa.

Comparative proteome analysis of drought-sensitive and drought-tolerant rapeseed roots and their hybrid F1 line under drought stress.

PubMed

Mohammadi, Payam Pour; Moieni, Ahmad; Komatsu, Setsuko

2012-11-01

Rapeseed (Brassica napus L.), which is the third leading source of vegetable oil, is sensitive to drought stress during the early vegetative growth stage. To investigate the initial response of rapeseed to drought stress, changes in the protein expression profiles of drought-sensitive (RGS-003) and drought-tolerant lines (SLM-003), and their F1 hybrid, were analyzed using a proteomics approach. Seven-day-old rapeseed seedlings were treated with drought stress by restricting water for 7 days, and proteins were extracted from roots and separated by two-dimensional polyacrylamide gel electrophoresis. In the sensitive rapeseed line, 35 protein spots were differentially expressed under drought stress, and proteins related to metabolism, energy, disease/defense, and transport were decreased. In the tolerant line, 32 protein spots were differentially expressed under drought stress, and proteins involved in metabolism, disease/defense, and transport were increased, while energy-related proteins were decreased. Six protein spots in F1 hybrid were common among expressed proteins in the drought-sensitive and -tolerant lines. Notably, tubulin beta-2 and heat shock protein 70 were decreased in the drought-sensitive line and hybrid F1 plants, while jasmonate-inducible protein and 20S proteasome subunit PAF1 were increased in the F1 hybrids and drought-tolerant line. These results indicate that (1) V-type H(+) ATPase, plasma-membrane associated cation-binding protein, HSP 90, and elongation factor EF-2 have a role in the drought tolerance of rapeseed; (2) The decreased levels of heat shock protein 70 and tubulin beta-2 in the drought-sensitive and hybrid F1 lines might explain the reduced growth of these lines in drought conditions.

Thiol specific oxidative stress response in Mycobacteria.

PubMed

Dosanjh, Nirpjit S; Rawat, Mamta; Chung, Ji-Hae; Av-Gay, Yossef

2005-08-01

The cellular response of mycobacteria to thiol specific oxidative stress was studied in Mycobacterium bovis BCG cultures. Two-dimensional gel electrophoresis revealed that upon diamide treatment at least 60 proteins were upregulated. Fourteen of these proteins were identified by MALDI-MS; four proteins, AhpC, Tpx, GroEL2, and GroEL1 are functionally related to oxidative stress response; eight proteins, LeuC, LeuD, Rv0224c, Rv3029c, AsnB, Rv2971, PheA and HisH are classified as part of the bacterial intermediary metabolism and respiration pathways; protein EchA14 belong to lipid metabolism, and NrdE, belongs to the mycobacterial information pathway category. Reverse transcription followed by quantitative real time PCR in response to diamide stress demonstrated that protein expression is directly proportional to the corresponding gene transcription.

Translation Stress Positively Regulates MscL-Dependent Excretion of Cytoplasmic Proteins

PubMed Central

Morra, Rosa; Del Carratore, Francesco; Muhamadali, Howbeer; Horga, Luminita Gabriela; Halliwell, Samantha

2018-01-01

ABSTRACT The apparent mislocalization or excretion of cytoplasmic proteins is a commonly observed phenomenon in both bacteria and eukaryotes. However, reports on the mechanistic basis and the cellular function of this so-called “nonclassical protein secretion” are limited. Here we report that protein overexpression in recombinant cells and antibiotic-induced translation stress in wild-type Escherichia coli cells both lead to excretion of cytoplasmic protein (ECP). Condition-specific metabolomic and proteomic analyses, combined with genetic knockouts, indicate a role for both the large mechanosensitive channel (MscL) and the alternative ribosome rescue factor A (ArfA) in ECP. Collectively, the findings indicate that MscL-dependent protein excretion is positively regulated in response to both osmotic stress and arfA-mediated translational stress. PMID:29382730

Proteomic and Biochemical Analyses of the Cotyledon and Root of Flooding-Stressed Soybean Plants

PubMed Central

Komatsu, Setsuko; Makino, Takahiro; Yasue, Hiroshi

2013-01-01

Background Flooding significantly reduces the growth and grain yield of soybean plants. Proteomic and biochemical techniques were used to determine whether the function of cotyledon and root is altered in soybean under flooding stress. Results Two-day-old soybean plants were flooded for 2 days, after which the proteins from root and cotyledon were extracted for proteomic analysis. In response to flooding stress, the abundance of 73 and 28 proteins was significantly altered in the root and cotyledon, respectively. The accumulation of only one protein, 70 kDa heat shock protein (HSP70) (Glyma17g08020.1), increased in both organs following flooding. The ratio of protein abundance of HSP70 and biophoton emission in the cotyledon was higher than those detected in the root under flooding stress. Computed tomography and elemental analyses revealed that flooding stress decreases the number of calcium oxalate crystal the cotyledon, indicating calcium ion was elevated in the cotyledon under flooding stress. Conclusion These results suggest that calcium might play one role through HSP70 in the cotyledon under flooding stress. PMID:23799004

Temporal and spatial expression and function of TaDlea3 in Triticum aestivum during developmental stages under drought stress.

PubMed

Chen, Juan; Fan, Lei; Du, Ya; Zhu, Weining; Tang, Ziqin; Li, Na; Zhang, Dapeng; Zhang, Linsheng

2016-11-01

Drought stress is a major factor limiting wheat growth and productivity. Late embryogenesis abundant (LEA) proteins are tolerant to water-related stress. To reveal the regulatory mechanisms of LEA proteins under drought stress, we cloned a novel group 3 LEA gene, namely, TaDlea3, from wheat (Triticum aestivum L.) Shaanhe 6. Subcellular localization assay showed that TaDlea3 protein accumulated in the cytoplasm. Quantitative real-time polymerase chain reaction results revealed that TaDlea3 expression was induced by drought stress. Western blot results indicated that TaDlea3 protein expression gradually increased with drought stress during four different developmental stages. Under normal conditions, no obvious phenotype difference was observed between the transgenic and wild-type seedlings. Meanwhile, the overexpression of TaDlea3 in Arabidopsis resulted in enhanced tolerance to drought stress, as determined by the assessment of antioxidant enzyme activities. Our results provide a basis for highly detailed functional analyses of LEA proteins and offer a promising approach for improving the tolerances of wheat cultivars to drought stress through genetic engineering. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A fucose containing polymer-rich fraction from the brown alga Ascophyllum nodosum mediates lifespan increase and thermal-tolerance in Caenorhabditis elegans, by differential effects on gene and protein expression.

PubMed

Kandasamy, Saveetha; Khan, Wajahatullah; Evans, Franklin D; Critchley, Alan T; Zhang, Junzeng; Fitton, J H; Stringer, Damien N; Gardiner, Vicki-Anne; Prithiviraj, Balakrishnan

2014-02-01

The extracts of the brown alga, Ascophyllum nodosum, which contains several bioactive compounds, have been shown to impart biotic and abiotic stress tolerance properties when consumed by animals. However, the physiological, biochemical and molecular mechanism underlying such effects remain elusive. We investigated the effect of A. nodosum fucose-containing polymer (FCP) on tolerance to thermally induced stress using the invertebrate animal model, Caenorhabditis elegans. FCP at a concentration of 150 μg mL(-1) significantly improved the life span and tolerance against thermally induced stress in C. elegans. The treatment increased the C. elegans survival by approximately 24%, when the animals were under severe thermally induced stress (i.e. 35 °C) and 27% under mild stress (i.e. 30 °C) conditions. The FCP induced differential expression of genes and proteins is associated with stress response pathways. Under thermal stress, FCP treatment significantly altered the expression of 65 proteins (54 up-regulated & 11 down-regulated). Putative functional analysis of FCP-induced differential proteins signified an association of altered proteins in stress-related molecular and biochemical pathways of the model worm.

Ampelopsin-induced reactive oxygen species enhance the apoptosis of colon cancer cells by activating endoplasmic reticulum stress-mediated AMPK/MAPK/XAF1 signaling

PubMed Central

Park, Ga Bin; Jeong, Jee-Yeong; Kim, Daejin

2017-01-01

Ampelopsin (Amp) is bioactive natural product and exerts anti-cancer effects against several cancer types. The present study investigated the anti-colon cancer activity of Amp and explored its mechanism of action. The treatment of colon cancer cells with Amp resulted in the dose- and time-dependent induction of apoptosis via the activation of endoplasmic reticulum (ER) stress, 5′ adenosine monophosphate-activated protein kinase (AMPK), and c-Jun N-terminal protein kinase (JNK)/p38 mitogen-activated protein kinases (MAPKs). Salubrinal, an ER stress inhibitor, prevented the upregulation of ER stress-associated proteins, including phosphorylated protein kinase RNA-like ER kinase, phosphorylated eukaryotic translation initiation factor 2α, glucose-regulated protein 78, and CCAAT/enhancer-binding protein homologous protein, as well as suppressing AMPK activation and the MAPK signaling pathway. Knockdown of AMPK by RNA interference failed to block ER stress. Additionally, SP600125 (a JNK inhibitor) and SB203580 (a p38-MAPK inhibitor) effectively inhibited apoptosis and attenuated the expression of X-linked IAP-associated factor 1 (XAF1) and apoptotic Bcl-2 family proteins (BCL2 antagonist/killer 1 and BCL2-associated X protein) in Amp-treated colon cancer cells. Furthermore, reactive oxygen species (ROS)-mediated ER stress/AMPK apoptotic signaling pathway in Amp-treated colon cancer cells were markedly inhibited by treatment with N-acetyl-L-cysteine, a ROS scavenger. These results demonstrate that treatment with Amp induces the apoptotic death of colon cancer cells through ER stress-initiated AMPK/MAPK/XAF1 signaling. These results also provide experimental information for developing Amp as therapeutic drug against colon cancer. PMID:29250183

TRPC1 Deletion Causes Striatal Neuronal Cell Apoptosis and Proteomic Alterations in Mice.

PubMed

Wang, Dian; Yu, Haitao; Xu, Benhong; Xu, Hua; Zhang, Zaijun; Ren, Xiaohu; Yuan, Jianhui; Liu, Jianjun; Guo, Yi; Spencer, Peter S; Yang, Xifei

2018-01-01

Transient receptor potential channel 1 (TRPC1) is widely expressed throughout the nervous system, while its biological role remains unclear. In this study, we showed that TRPC1 deletion caused striatal neuronal loss and significantly increased TUNEL-positive and 8-hydroxy-2'-deoxyguanosine (8-OHdG) staining in the striatum. Proteomic analysis by two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with mass spectrometry (MS) revealed a total of 51 differentially expressed proteins (26 increased and 25 decreased) in the stratum of TRPC1 knockout (TRPC1 -/- ) mice compared to that of wild type (WT) mice. Bioinformatics analysis showed these dysregulated proteins included: oxidative stress-related proteins, synaptic proteins, endoplasmic reticulum (ER) stress-related proteins and apoptosis-related proteins. STRING analysis showed these differential proteins have a well-established interaction network. Based on the proteomic data, we revealed by Western-blot analysis that TRPC1 deletion caused ER stress as evidenced by the dysregulation of GRP78 and PERK activation-related signaling pathway, and elevated oxidative stress as suggested by increased 8-OHdG staining, increased NADH dehydrogenase (ubiquinone) flavoprotein 2 (NDUV2) and decreased protein deglycase (DJ-1), two oxidative stress-related proteins. In addition, we also demonstrated that TRPC1 deletion led to significantly increased apoptosis in striatum with concurrent decrease in both 14-3-3Z and dynamin-1 (D2 dopamine (DA) receptor binding), two apoptosis-related proteins. Taken together, we concluded that TRPC1 deletion might cause striatal neuronal apoptosis by disturbing multiple biological processes (i.e., ER stress, oxidative stress and apoptosis-related signaling). These data suggest that TRPC1 may be a key player in the regulation of striatal cellular survival and death.

Comparative proteomic analysis of the stolon cold stress response between the C4 perennial grass species Zoysia japonica and Zoysia metrella.

PubMed

Xuan, Jiping; Song, Yufeng; Zhang, Hongxiao; Liu, Jianxiu; Guo, Zhongren; Hua, Yuelou

2013-01-01

Zoysiagrass, the most cold-tolerant grass among the warm-season turfgrasses, is often used as a model species for isolating cellular components related to cold stress. To understand the proteomic responses to cold stress in zoysiagrass stolons, we extracted stolon proteins from Zoysiajaponica, cv. Meyer (cold-tolerant) and Z. metrella, cv. Diamond (cold-sensitive), which were grown with or without cold treatment. Approximately 700 proteins were resolved on 2-DE gels, and 70 protein spots were differentially accumulated. We further observed that 45 of the identified proteins participate in 10 metabolic pathways and cellular processes. A significantly greater number of proteins accumulated in the Meyer than in the Diamond and 15 increased proteins were detected only in the Meyer cultivar under cold stress. Furthermore, we propose a cold stress-responsive protein network composed of several different functional components that exhibits a balance between reactive oxygen species (ROS) production and scavenging, accelerated protein biosynthesis and proteolysis, reduced protein folding, enhanced photosynthesis, abundant energy supply and enhanced biosynthesis of carbohydrates and nucleotides. Generally, the cold-tolerant Meyer cultivar showed a greater ROS scavenging ability, more abundant energy supply and increased photosynthesis and protein synthesis than did the cold-sensitive Diamond cultivar, which may partly explain why Meyer is more cold tolerant.

Proteomic response of mouse pituitary gland under heat stress revealed active regulation of stress responsive proteins.

PubMed

Memon, Shahar Bano; Lian, Li; Gadahi, Javaid Ali; Genlin, Wang

2016-10-01

The mapping of tissue proteomes can identify the molecular regulators and effectors of their physiological activity. However, proteomic response of a mammalian tissue against heat stress (HS) particularly of the pituitary gland has not yet been resolved. The proteomic response of the mouse pituitary gland against HS at 40 o C was evaluated by iTRAQ. We found that, HS actively regulates stress-related proteins. Among 375 differentially expressed proteins, 26 up and 46 downregulated proteins were found as stress responsive proteins. Two proteins belonging to the HSP70 and one to HSP90 family were found upregulated. Meanwhile, the expression of HSP90α (Cytosolic), HSP60, and HSP84b were observed to be downregulated. A neuroprotective enzyme Nmnat3 was observed to be significantly upregulated. Three proteins related to the intermediate filament (IF) proteins (lamins, vimentin and keratins) were also found to be upregulated. We reported, an association between the IF proteins and HSPs as a biological marker of HS. The expression of Apo A-IV was upregulated and might be one explanation for low food intake during HS. Our findings indicated that, differentially expressed proteins might be played important roles in combating HS. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mitogen-activated protein kinase cascades in Vitis vinifera

PubMed Central

Çakır, Birsen; Kılıçkaya, Ozan

2015-01-01

Protein phosphorylation is one of the most important mechanisms to control cellular functions in response to external and endogenous signals. Mitogen-activated protein kinases (MAPK) are universal signaling molecules in eukaryotes that mediate the intracellular transmission of extracellular signals resulting in the induction of appropriate cellular responses. MAPK cascades are composed of four protein kinase modules: MAPKKK kinases (MAPKKKKs), MAPKK kinases (MAPKKKs), MAPK kinases (MAPKKs), and MAPKs. In plants, MAPKs are activated in response to abiotic stresses, wounding, and hormones, and during plant pathogen interactions and cell division. In this report, we performed a complete inventory of MAPK cascades genes in Vitis vinifera, the whole genome of which has been sequenced. By comparison with MAPK, MAPK kinases, MAPK kinase kinases and MAPK kinase kinase kinase kinase members of Arabidopsis thaliana, we revealed the existence of 14 MAPKs, 5 MAPKKs, 62 MAPKKKs, and 7 MAPKKKKs in Vitis vinifera. We identified orthologs of V. vinifera putative MAPKs in different species, and ESTs corresponding to members of MAPK cascades in various tissues. This work represents the first complete inventory of MAPK cascades in V. vinifera and could help elucidate the biological and physiological functions of these proteins in V. vinifera. PMID:26257761

Two-Dimensional Gel Electrophoresis: Discovering Biomolecules for Environmental Bioremediation

NASA Astrophysics Data System (ADS)

Singh, Om V.; Chandel, Anuj K.

Environmental contamination has been viewed as an ecological malaise for which bioremediation can be prescribed as a “perfect medicine.” The solution to the problems with bioremediation lies in analyzing to what extent the microbes’ physiological machinery contributes to the degradation process and which biomolecules and their mechanisms are responsible for regulatory factors within the degradation system, such as protein, metabolite, and enzymatic chemical transformation. In the post-genomic era, recent advances in proteomics have allowed us to elucidate many complex biological mechanisms. Two-dimensional gel electrophoresis (2DE) in conjunction with mass spectrometry (MS) can be utilized to identify the biomolecules and their molecular mechanisms in bioremediation. A set of highly abundant global proteins over a pI range 4-7 was separated and compared by size fractionation (25-100 kDa) on 2DE. We identified a set of catabolic proteins, enzymes, and heat shock molecular chaperones associated with the regulatory network that was found to be overexpressed under phenol-stressed conditions. This chapter also offers optimized ideal directions for 2DE, followed by easy-to-follow directions for a protein identification strategy using MALDI-TOF and targeting novel proteins/enzymes for a universal set of experiments.

Percolation mechanism drives actin gels to the critically connected state

NASA Astrophysics Data System (ADS)

Lee, Chiu Fan; Pruessner, Gunnar

2016-05-01

Cell motility and tissue morphogenesis depend crucially on the dynamic remodeling of actomyosin networks. An actomyosin network consists of an actin polymer network connected by cross-linker proteins and motor protein myosins that generate internal stresses on the network. A recent discovery shows that for a range of experimental parameters, actomyosin networks contract to clusters with a power-law size distribution [J. Alvarado, Nat. Phys. 9, 591 (2013), 10.1038/nphys2715]. Here, we argue that actomyosin networks can exhibit a robust critical signature without fine-tuning because the dynamics of the system can be mapped onto a modified version of percolation with trapping (PT), which is known to show critical behavior belonging to the static percolation universality class without the need for fine-tuning of a control parameter. We further employ our PT model to generate experimentally testable predictions.

Tomato yellow leaf curl virus infection mitigates the heat stress response of plants grown at high temperatures

PubMed Central

Ghandi, Anfoka; Adi, Moshe; Lilia, Fridman; Linoy, Amrani; Or, Rotem; Mikhail, Kolot; Mouhammad, Zeidan; Henryk, Czosnek; Rena, Gorovits

2016-01-01

Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared. The plant heat-stress response was undermined in TYLCV infected plants. The decline correlated with the down-regulation of heat shock transcription factors (HSFs) HSFA2 and HSFB1, and consequently, of HSF-regulated genes Hsp17, Apx1, Apx2 and Hsp90. We proposed that the weakened heat stress response was due to the decreased capacity of HSFA2 to translocate into the nuclei of infected cells. All the six TYLCV proteins were able to interact with tomato HSFA2 in vitro, moreover, coat protein developed complexes with HSFA2 in nuclei. Capturing of HSFA2 by viral proteins could suppress the transcriptional activation of heat stress response genes. Application of both heat and TYLCV stresses was accompanied by the development of intracellular large protein aggregates containing TYLCV proteins and DNA. The maintenance of cellular chaperones in the aggregated state, even after recovery from heat stress, prevents the circulation of free soluble chaperones, causing an additional decrease in stress response efficiency. PMID:26792235

Comparative protein profiles of Butea superba tubers under seasonal changes.

PubMed

Leelahawong, Chonchanok; Srisomsap, Chantragan; Cherdshewasart, Wichai; Chokchaichamnankit, Daranee; Vinayavekhin, Nawaporn; Sangvanich, Polkit

2016-07-01

Seasonal changes are major factors affecting environmental conditions which induce multiple stresses in plants, leading to changes in protein relative abundance in the complex cellular plant metabolic pathways. Proteomics was applied to study variations in proteome composition of Butea. superba tubers during winter, summer and rainy season throughout the year using two-dimensional polyacrylamide gel electrophoresis coupled with a nanoflow liquid chromatography coupled to electrospray ionization quadrupole-time-of-flight tandem mass spectrometry. A total of 191 protein spots were identified and also classified into 12 functional groups. The majority of these were mainly involved in carbohydrate and energy metabolism (30.37 %) and defense and stress (18.32 %). The results exhibited the highest numbers of identified proteins in winter-harvested samples. Forty-five differential proteins were found in different seasons, involving important metabolic pathways. Further analysis indicated that changes in the protein levels were due mainly to temperature stress during summer and to water stress during winter, which affected cellular structure, photosynthesis, signal transduction and homeostasis, amino-acid biosynthesis, protein destination and storage, protein biosynthesis and stimulated defense and stress mechanisms involving glycolytic enzymes and relative oxygen species catabolizing enzymes. The proteins with differential relative abundances might induce an altered physiological status within plant tubers for survival. The work provided new insights into the better understanding of the molecular basis of plant proteomes and stress tolerance mechanisms, especially during seasonal changes. The finding suggested proteins that might potentially be used as protein markers in differing seasons in other plants and aid in selecting B. superba tubers with the most suitable medicinal properties in the future.

Metabolic and oxidative stress markers in Wistar rats after 2 months on a high-fat diet.

PubMed

Auberval, Nathalie; Dal, Stéphanie; Bietiger, William; Pinget, Michel; Jeandidier, Nathalie; Maillard-Pedracini, Elisa; Schini-Kerth, Valérie; Sigrist, Séverine

2014-01-01

Metabolic syndrome is associated with an increased risk of cardiovascular and hepatic complications. Oxidative stress in metabolic tissues has emerged as a universal feature of metabolic syndrome and its co-morbidities. We aimed to develop a rapidly and easily induced model of metabolic syndrome in rats to evaluate its impact on plasma and tissue oxidative stress. Metabolic syndrome was induced in rats using a high-fat diet (HFD), and these rats were compared to rats fed a normal diet (ND) for 2 months. Metabolic control was determined by measuring body weight, blood glucose, triglycerides, lipid peroxidation and protein carbonylation in plasma. Insulinemia was evaluated through the measure of C-peptide. Histological analysis was performed on the pancreas, liver and blood vessels. After 2 months, the HFD induced an increase in body weight, insulin and triglycerides. Liver steatosis was also observed in the HFD group, which was associated with an increase in glycogen storage. In the pancreas, the HFD induced islet hyperplasia. Tissue oxidative stress was also increased in the liver, pancreas and blood vessels, but plasma oxidative stress remained unchanged. This paper reports the development of a fast and easy model of rat metabolic syndrome associated with tissue oxidative stress. This model may be a good tool for the biological validation of drugs or antioxidants to limit or prevent the complications of metabolic syndrome.

Stress-induced alterations in 5-HT1A receptor transcriptional modulators NUDR and Freud-1.

PubMed

Szewczyk, Bernadeta; Kotarska, Katarzyna; Daigle, Mireille; Misztak, Paulina; Sowa-Kucma, Magdalena; Rafalo, Anna; Curzytek, Katarzyna; Kubera, Marta; Basta-Kaim, Agnieszka; Nowak, Gabriel; Albert, Paul R

2014-11-01

The effect of stress on the mRNA and protein level of the 5-HT1A receptor and two of its key transcriptional modulators, NUDR and Freud-1, was examined in the prefrontal cortex (PFC) and hippocampus (Hp) using rodent models: olfactory bulbectomy (OB) and prenatal stress (PS) in male and female rats; chronic mild stress in male rats (CMS) and pregnancy stress. In PFC, CMS induced the most widespread changes, with significant reduction in both mRNA and protein levels of NUDR, 5-HT1A receptor and in Freud-1 mRNA; while in Hp 5-HT1A receptor and Freud-1 protein levels were also decreased. In male, but not female OB rats PFC Freud-1 and 5-HT1A receptor protein levels were reduced, while in Hp 5-HT1A receptor, Freud-1 and NUDR mRNA's but not protein were reduced. In PS rats PFC 5-HT1A receptor protein was reduced more in females than males; while in Hp Freud-1 protein was increased in females. In pregnancy stress, PFC NUDR, Freud-1 and 5-HT1A protein receptor levels were reduced, and in HP 5-HT1A receptor protein levels were also reduced; in HP only NUDR and Freud-1 mRNA levels were reduced. Overall, CMS and stress during pregnancy produced the most salient changes in 5-HT1A receptor and transcription factor expression, suggesting a primary role for altered transcription factor expression in chronic regulation of 5-HT1A receptor expression. By contrast, OB (in males) and PS (in females) produced gender-specific reductions in PFC 5-HT1A receptor protein levels, suggesting a role for post-transcriptional regulation. These and previous data suggest that chronic stress might be a key regulator of NUDR/Freud-1 gene expression.

Stress-induced alterations in 5-HT1A receptor transcriptional modulators NUDR and Freud-1

PubMed Central

Szewczyk, Bernadeta; Kotarska, Katarzyna; Daigle, Mireille; Misztak, Paulina; Sowa-Kucma, Magdalena; Rafalo, Anna; Curzytek, Katarzyna; Kubera, Marta; Basta-Kaim, Agnieszka; Nowak, Gabriel; Albert, Paul R

2015-01-01

The effect of stress on the mRNA and protein level of the 5-HT1A receptor and two of its key transcriptional modulators, NUDR and Freud-1, was examined in the prefrontal cortex (PFC) and hippocampus (Hp) using rodent models: olfactory bulbectomy (OB) and prenatal stress (PS) in male and female rats; chronic mild stress in male rats (CMS) and pregnancy stress. In PFC, CMS induced the most widespread changes, with significant reduction in both mRNA and protein levels of NUDR, 5-HT1A receptor and in Freud-1 mRNA; while in Hp 5-HT1A receptor and Freud-1 protein levels were also decreased. In male, but not female OB rats PFC Freud-1 and 5-HT1A receptor protein levels were reduced, while in Hp 5-HT1A receptor, Freud-1 and NUDR mRNA’s but not protein were reduced. In PS rats PFC 5-HT1A receptor protein was reduced more in females than males; while in Hp Freud-1 protein was increased in females. In pregnancy stress, PFC NUDR, Freud-1 and 5-HT1A protein receptor levels were reduced, and in HP 5-HT1A receptor protein levels were also reduced; in HP only NUDR and Freud-1 mRNA levels were reduced. Overall, CMS and stress during pregnancy produced the most salient changes in 5-HT1A receptor and transcription factor expression, suggesting a primary role for altered transcription factor expression in chronic regulation of 5-HT1A receptor expression. By contrast, OB (in males) and PS (in females) produced gender-specific reductions in PFC 5-HT1A receptor protein levels, suggesting a role for post-transcriptional regulation. These and previous data suggest that chronic stress might be a key regulator of NUDR/Freud-1 gene expression. PMID:24946016

Three-dimensional stress field around a membrane protein: atomistic and coarse-grained simulation analysis of gramicidin A.

PubMed

Yoo, Jejoong; Cui, Qiang

2013-01-08

Using both atomistic and coarse-grained (CG) models, we compute the three-dimensional stress field around a gramicidin A (gA) dimer in lipid bilayers that feature different degrees of negative hydrophobic mismatch. The general trends in the computed stress field are similar at the atomistic and CG levels, supporting the use of the CG model for analyzing the mechanical features of protein/lipid/water interfaces. The calculations reveal that the stress field near the protein-lipid interface exhibits a layered structure with both significant repulsive and attractive regions, with the magnitude of the stress reaching 1000 bar in certain regions. Analysis of density profiles and stress field distributions helps highlight the Trp residues at the protein/membrane/water interface as mechanical anchors, suggesting that similar analysis is useful for identifying tension sensors in other membrane proteins, especially membrane proteins involved in mechanosensation. This work fosters a connection between microscopic and continuum mechanics models for proteins in complex environments and makes it possible to test the validity of assumptions commonly made in continuum mechanics models for membrane mediated processes. For example, using the calculated stress field, we estimate the free energy of membrane deformation induced by the hydrophobic mismatch, and the results for regions beyond the annular lipids are in general consistent with relevant experimental data and previous theoretical estimates using elasticity theory. On the other hand, the assumptions of homogeneous material properties for the membrane and a bilayer thickness at the protein/lipid interface being independent of lipid type (e.g., tail length) appear to be oversimplified, highlighting the importance of annular lipids of membrane proteins. Finally, the stress field analysis makes it clear that the effect of even rather severe hydrophobic mismatch propagates to only about two to three lipid layers, thus putting a limit on the range of cooperativity between membrane proteins in crowded cellular membranes. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Physiological and proteomic analyses of the drought stress response in Amygdalus Mira (Koehne) Yü et Lu roots.

PubMed

Cao, Yuan; Luo, Qiuxiang; Tian, Yan; Meng, Fanjuan

2017-02-27

Plants are oftentimes exposed to many types of abiotic stresses. Drought is one of the main environmental stresses which limits plant growth, distribution and crop yield worldwide. Amygdalus mira (Koehne) Yü et Lu is an important wild peach, and it is considered an ideal wild peach germplasm for improving cultivated peach plants. Because of the loss of genetic variation, cultivated peach plants are sensitive to biotic and abiotic stresses. Wild peach germplasm can offer many useful genes for peach improvement. Responses to drought by withholding water have been studied in Amygdalus mira (Koehne) Yü et Lu roots. In this study, plants were divided into well-watered (control) and water-stressed (treatment) groups, and the treatment group did not receive water until the recovery period (day 16). Several physiological parameters, including root water content and root length, were reduced by drought stress and recovered after rewatering. In addition, the relative conductivity, the levels of proline, MDA and H 2 O 2 , and the activities of ROS scavenging enzymes (POD, APX and CAT) were increased, and none of these factors, except the level of proline, recovered after rewatering. In total, 95 differentially expressed proteins were revealed after drought. The identified proteins refer to a extensive range of biological processes, molecular functions and cellular components, including cytoskeleton dynamics (3.16% of the total 95 proteins), carbohydrate and nitrogen metabolism (6.33% of the total 95 proteins), energy metabolism (7.37% of the total 95 proteins), transcription and translation (18.95% of the total 95 proteins), transport (4.21% of the total 95 proteins), inducers (3.16% of the total 95 proteins), stress and defense (26.31% of the total 95 proteins), molecular chaperones (9.47% of the total 95 proteins), protein degradation (3.16% of the total 95 proteins), signal transduction (7.37% of the total 95 proteins), other materials metabolism (5.26% of the total 95 proteins) and unknown functions (5.26% of the total 95 proteins). Proteins related to defense, stress, transcription and translation play an important role in drought response. In addition, we also examined the correlation between protein and transcript levels. The interaction between enzymatic and non-enzymatic antioxidants, the levels of proline, MDA, H 2 O 2 and the relative conductivity, and the expression level of proteins in drought-treated plants all contribute to drought resistance in Amygdalus mira (Koehne) Yü et Lu.

dFOXO Activates Large and Small Heat Shock Protein Genes in Response to Oxidative Stress to Maintain Proteostasis in Drosophila.

PubMed

Donovan, Marissa R; Marr, Michael T

2016-09-02

Maintaining protein homeostasis is critical for survival at the cellular and organismal level (Morimoto, R. I. (2011) Cold Spring Harb. Symp. Quant. Biol. 76, 91-99). Cells express a family of molecular chaperones, the heat shock proteins, during times of oxidative stress to protect against proteotoxicity. We have identified a second stress responsive transcription factor, dFOXO, that works alongside the heat shock transcription factor to activate transcription of both the small heat shock protein and the large heat shock protein genes. This expression likely protects cells from protein misfolding associated with oxidative stress. Here we identify the regions of the Hsp70 promoter essential for FOXO-dependent transcription using in vitro methods and find a physiological role for FOXO-dependent expression of heat shock proteins in vivo. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Initiation of the Immune Response by Extracellular Hsp72: Chaperokine Activity of Hsp72

PubMed Central

Asea, Alexzander

2007-01-01

Heat shock proteins exert their beneficial effects via basically two modes of action depending on their relative location within the host. Intracellular heat shock proteins found within cells serve a cytoprotective role by chaperoning naïve, misfolded and/or denatured proteins in response to stressful stimuli by a process known as the stress response. However, stressful stimuli also induce the release of intracellular heat shock proteins into the extracellular milieu and circulation. The extracellular heat shock protein proteins serve a cytostimulatory role by initiating immune responses designed to fend off microbial infection and destroy neoplastic transformed cells. This review will briefly cover recent advances into elucidating the mechanism(s) by which stress induces the release of heat shock proteins into the circulation, how it initiates immune responses and suggest the possible biological significance of circulating Hsp to the host. PMID:17502920

Initiation of the Immune Response by Extracellular Hsp72: Chaperokine Activity of Hsp72.

PubMed

Asea, Alexzander

2006-08-01

Heat shock proteins exert their beneficial effects via basically two modes of action depending on their relative location within the host. Intracellular heat shock proteins found within cells serve a cytoprotective role by chaperoning naïve, misfolded and/or denatured proteins in response to stressful stimuli by a process known as the stress response. However, stressful stimuli also induce the release of intracellular heat shock proteins into the extracellular milieu and circulation. The extracellular heat shock protein proteins serve a cytostimulatory role by initiating immune responses designed to fend off microbial infection and destroy neoplastic transformed cells. This review will briefly cover recent advances into elucidating the mechanism(s) by which stress induces the release of heat shock proteins into the circulation, how it initiates immune responses and suggest the possible biological significance of circulating Hsp to the host.

Functional analysis of structurally related soybean GmWRKY58 and GmWRKY76 in plant growth and development.

PubMed

Yang, Yan; Chi, Yingjun; Wang, Ze; Zhou, Yuan; Fan, Baofang; Chen, Zhixiang

2016-08-01

WRKY transcription factors constitute a large protein superfamily with a predominant role in plant stress responses. In this study we report that two structurally related soybean WRKY proteins, GmWRKY58 and GmWRKY76, play a critical role in plant growth and flowering. GmWRKY58 and GmWRKY76 are both Group III WRKY proteins with a C2HC zinc finger domain and are close homologs of AtWRKY70 and AtWRKY54, two well-characterized Arabidopsis WRKY proteins with an important role in plant responses to biotic and abiotic stresses. GmWRKY58 and GmWRKY76 are both localized to the nucleus, recognize the TTGACC W-box sequence with a high specificity, and function as transcriptional activators in both yeast and plant cells. Expression of GmWRKY58 and GmWRKY76 was detected at low levels in roots, stem, leaves, flowers, and pods. Expression of the two genes in leaves increased substantially during the first 4 weeks after germination but steadily declined thereafter with increased age. To determine their biological functions, transgenic Arabidopsis plants were generated overexpressing GmWRKY58 or GmWRKY76 Unlike AtWRKY70 and AtWRKY54, overexpression of GmWRKY58 or GmWRKY76 had no effect on disease resistance and only small effects on abiotic stress tolerance of the transgenic plants. Significantly, transgenic Arabidopsis plants overexpressing GmWRKY58 or GmWRKY76 flowered substantially earlier than control plants and this early flowering phenotype was associated with increased expression of several flowering-promoting genes, some of which are enriched in W-box sequences in their promoters recognized by GmWRKY58 and GmWRKY76. In addition, virus-induced silencing of GmWRKY58 and GmWRKY76 in soybean resulted in stunted plants with reduced leaf expansion and terminated stem growth. These results provide strong evidence for functional divergence among close structural homologs of WRKY proteins from different plant species. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Poliovirus infection induces the co-localization of cellular protein SRp20 with TIA-1, a cytoplasmic stress granule protein

PubMed Central

Fitzgerald, Kerry D.; Semler, Bert L.

2013-01-01

Different types of environmental stress cause mammalian cells to form cytoplasmic foci, termed stress granules, which contain mRNPs that are translationally silenced. These foci are transient and dynamic, and contain components of the cellular translation machinery as well as certain mRNAs and RNA binding proteins. Stress granules are known to be induced by conditions such as hypoxia, nutrient deprivation, and oxidative stress, and a number of cellular factors have been identified that are commonly associated with these foci. More recently it was discovered that poliovirus infection also induces the formation of stress granules, although these cytoplasmic foci appear to be somewhat compositionally unique. Work described here examined the punctate pattern of SRp20 (a host cell mRNA splicing protein) localization in the cytoplasm of poliovirus-infected cells, demonstrating the partial co-localization of SRp20 with the stress granule marker protein TIA-1. We determined that SRp20 does not co-localize with TIA-1, however, under conditions of oxidative stress, indicating that the close association of these two proteins during poliovirus infection is not representative of a general response to cellular stress. We confirmed that the expression of a dominant negative version of TIA-1 (TIA-1-PRD) results in the dissociation of stress granules. Finally, we demonstrated that expression of wild type TIA-1 or dominant negative TIA-1-PRD in cells during poliovirus infection does not dramatically affect viral translation. Taken together, these studies provide a new example of the unique cytoplasmic foci that form during poliovirus infection. PMID:23830997

The Role of Endoplasmic Reticulum Stress in Human Pathology

PubMed Central

Oakes, Scott A.; Papa, Feroz R.

2017-01-01

Numerous genetic and environmental insults impede the ability of cells to properly fold and posttranslationally modify secretory and transmembrane proteins in the endoplasmic reticulum (ER), leading to a buildup of misfolded proteins in this organelle—a condition called ER stress. ER-stressed cells must rapidly restore protein-folding capacity to match protein-folding demand if they are to survive. In the presence of high levels of misfolded proteins in the ER, an intracellular signaling pathway called the unfolded protein response (UPR) induces a set of transcriptional and translational events that restore ER homeostasis. However, if ER stress persists chronically at high levels, a terminal UPR program ensures that cells commit to self-destruction. Chronic ER stress and defects in UPR signaling are emerging as key contributors to a growing list of human diseases, including diabetes, neurodegeneration, and cancer. Hence, there is much interest in targeting components of the UPR as a therapeutic strategy to combat these ER stress–associated pathologies. PMID:25387057

Lack of A-factor production induces the expression of nutrient scavenging and stress-related proteins in Streptomyces griseus.

PubMed

Birkó, Zsuzsanna; Swiatek, Magdalena; Szájli, Emília; Medzihradszky, Katalin F; Vijgenboom, Erik; Penyige, András; Keseru, Judit; van Wezel, Gilles P; Biró, Sándor

2009-10-01

The small gamma-butyrolactone A-factor is an important autoregulatory signaling molecule for the soil-inhabiting streptomycetes. Starvation is a major trigger for development, and nutrients are provided by degradation of the vegetative mycelium via a process of programmed cell death, reusing proteins, nucleic acids, and cell wall material. The A-factor regulon includes many extracellular hydrolases. Here we show via proteomics analysis that many nutrient-scavenging and stress-related proteins were overexpressed in an A-factor non-producing mutant of Streptomyces griseus B-2682. Transcript analysis showed that this is primarily due to differential transcription of the target genes during early development. The targets include proteins relating to nutrient stress and environmental stress and an orthologue of the Bacillus sporulation control protein Spo0M. The enhanced expression of these proteins underlines the stress that is generated by the absence of A-factor. Wild-type developmental gene expression was restored to the A-factor non-producing mutant by the signaling protein Factor C in line with our earlier observation that Factor C triggers A-factor production.

[From a Ph.D. Thesis: Understanding the Past, Predicting the Future].

PubMed

Watanabe, Kenichi

2018-01-01

　Posey et al. have reported multiple molecular diagnoses in 4.5% of cases (101/2076) in which whole-exome sequencing was informative. Distinct disease phenotypes affect different organ systems, whereas overlapping disease phenotypes are more likely to be caused by two genes encoding proteins that interact within the same pathway. My research projects at the Niigata University of Pharmacy have investigated underlying mechanisms involved in human disease, including fatty acid metabolism, diabetic cardiomyopathy, atopic dermatitis, colitis, hepatitis, etc. Three students from abroad graduated this year from the Department of Clinical Pharmacology, Niigata University of Pharmacy and Applied Life Sciences. These students reported on treatments for heart disease, non-alcoholic steatohepatitis and atopic dermatitis, as well as the underlying mechanisms involved in each. The titles of these reports are "Study of the role of cardiac 14-3-3η protein in cardiac inflammation and adverse cardiac remodeling during heart failure in mice", "Non-alcoholic steatohepatitis: onset of mechanisms under diabetic background and treatment strategies" and "The role of HMGB1 and its cascade signaling pathway in atopic dermatitis". It can be concluded from these three theses that oxidative stress and inflammation are among the principal mechanisms underlying these diseases.

Differential impact of environmental stresses on the pea mitochondrial proteome.

PubMed

Taylor, Nicolas L; Heazlewood, Joshua L; Day, David A; Millar, A Harvey

2005-08-01

Exposure to adverse environmental conditions causes oxidative stress in many organisms, leading either to disease and debilitation or to response and tolerance. Mitochondria are a key site of oxidative stress and of cellular response and play important roles in cell survival. We analyzed the response of mitochondria in pea (Pisum sativum) plants to the common stresses associated with drought, cold, and herbicides. These treatments all altered photosynthetic and respiratory rates of pea leaves to various extents, but only herbicides significantly increased lipid peroxidation product accumulation. Mitochondria isolated from the stressed pea plants maintained their electron transport chain activity, but changes were evident in the abundance of uncoupling proteins, non-phosphorylating respiratory pathways, and oxidative modification of lipoic acid moieties on mitochondrial proteins. These data suggest that herbicide treatment placed a severe oxidative stress on mitochondria, whereas chilling and particularly drought were milder stresses. Detailed analysis of the soluble proteome of mitochondria by gel electrophoresis and mass spectrometry revealed differential degradation of key matrix enzymes during treatments with chilling being significantly more damaging than drought. Differential induction of heat shock proteins and specific losses of other proteins illustrated the diversity of response to these stresses at the protein level. Cross-species matching was required for mass spectrometry identification of nine proteins because only a limited number of pea cDNAs have been sequenced, and the full pea genome is not available. Blue-native separation of intact respiratory chain complexes revealed little if any change in response to environmental stresses. Together these data suggest that although many of the molecular events identified by chemical stresses of mitochondria from a range of model eukaryotes are also apparent during environmental stress of plants, their extent and significance can vary substantially.

Anti-Apoptotic Protein Bcl-xL Expression in the Midbrain Raphe Region Is Sensitive to Stress and Glucocorticoids.

PubMed

Shishkina, Galina T; Kalinina, Tatyana S; Bulygina, Veta V; Lanshakov, Dmitry A; Babluk, Ekaterina V; Dygalo, Nikolay N

2015-01-01

Anti-apoptotic proteins are suggested to be important for the normal health of neurons and synapses as well as for resilience to stress. In order to determine whether stressful events may influence the expression of anti-apoptotic protein Bcl-xL in the midbrain and specifically in the midbrain serotonergic (5-HT) neurons involved in neurobehavioral responses to adverse stimuli, adult male rats were subjected to short-term or chronic forced swim stress. A short-term stress rapidly increased the midbrain bcl-xl mRNA levels and significantly elevated Bcl-xL immunoreactivity in the midbrain 5-HT cells. Stress-induced increase in glucocorticoid secretion was implicated in the observed effect. The levels of bcl-xl mRNA were decreased after stress when glucocorticoid elevation was inhibited by metyrapone (MET, 150 mg/kg), and this decrease was attenuated by glucocorticoid replacement with dexamethasone (DEX; 0.2 mg/kg). Both short-term stress and acute DEX administration, in parallel with Bcl-xL, caused a significant increase in tph2 mRNA levels and slightly enhanced tryptophan hydroxylase immunoreactivity in the midbrain. The increasing effect on the bcl-xl expression was specific to the short-term stress. Forced swim repeated daily for 2 weeks led to a decrease in bcl-xl mRNA in the midbrain without any effects on the Bcl-xL protein expression in the 5-HT neurons. In chronically stressed animals, an increase in tph2 gene expression was not associated with any changes in tryptophan hydroxylase protein levels. Our findings are the first to demonstrate that both short-term stress and acute glucocorticoid exposures induce Bcl-xL protein expression in the midbrain 5-HT neurons concomitantly with the activation of the 5-HT synthesis pathway in these neurons.

Perceived stress and bruxism in university students.

PubMed

Cavallo, Pierpaolo; Carpinelli, Luna; Savarese, Giulia

2016-12-21

Many studies have shown the correlation between bruxism and stress that affects the quality of life of university students. The present study highlights this correlation-for the first time-in a group of university students in Italy. We have investigated the prevalence of awake and asleep bruxism and its correlation with perceived stress in a group of 278 Italian undergraduate students (117 M). A self report questionnaire was constructed using a socio-demographic test, the Perceived Stress Scale (PSS) and the item n. 8 of the Fonseca Questionnaire for presence of bruxism. The perceived stress score using PSS-10 scale was 32.2 (SD 4.6, 95% CL 31.6-32.7) for all the subjects, with significant gender difference: M = 31.2 and F = 32.9 (P = 0.0019). The prevalence for awake bruxism was 37.9% (F = 40.8%; M = 34.2%,), while for sleep bruxism was 31.8% (F = 33.3%; M = 29.1%), both without significant gender difference. A positive correlation, with significant concordance and dependence, between stress score and awake bruxism was present for male students only. University students showed higher bruxism and stress levels compared to the general population, with higher stress for females, but, even if female students show higher stress, a correlation between stress and bruxism exists only for male gender. Further studies should be performed.

Endoplasmic reticulum stress inhibits expression of genes involved in thyroid hormone synthesis and their key transcriptional regulators in FRTL-5 thyrocytes

PubMed Central

Wen, Gaiping; Eder, Klaus

2017-01-01

Endoplasmic reticulum (ER) stress is characterized by the accumulation of misfolded proteins due to an impairment of ER quality control pathways leading to the activation of a defense system, called unfolded protein response (UPR). While thyrocytes are supposed to be highly susceptible to environmental conditions that cause ER stress due to the synthesis of large amounts of secretory proteins required for thyroid hormone synthesis, systematic investigations on the effect of ER stress on expression of key genes of thyroid hormone synthesis and their transcriptional regulators are lacking. Since the aim of the ER stress-induced UPR is to restore ER homeostasis and to facilitate cell survival through transient shutdown of ribosomal protein translation, we hypothesized that the expression of genes involved in thyroid hormone synthesis and their transcriptional regulators, all of which are not essential for cell survival, are down-regulated in thyrocytes during ER stress, while sterol regulatory element-binding proteins (SREBPs) are activated during ER stress in thyrocytes. Treatment of FRTL-5 thyrocytes with the ER stress inducer tunicamycin (TM) dose-dependently increased the mRNA and/or protein levels of known UPR target genes, stimulated phosphorylation of the ER stress sensor protein kinase RNA-like ER kinase (PERK) and of the PERK target protein eukaryotic initiation factor 2α (eIF2α) and caused splicing of the ER stress-sensitive transcription factor X-box binding protein (XBP-1) (P < 0.05). The mRNA levels and/or protein levels of genes involved in thyroid hormone synthesis, sodium/iodide symporter (NIS), thyroid peroxidase (TPO) and thyroglobulin (TG), their transcriptional regulators and thyrotropin (TSH) receptor and the uptake of Na125I were reduced at the highest concentration of TM tested (0.1 μg/mL; P < 0.05). Proteolytic activation of the SREBP-1c pathway was not observed in FRTL-5 cells treated with TM, whereas TM reduced proteolytic activation of the SREBP-2 pathway at 0.1 μg TM/mL (P < 0.05). In conclusion, the expression of key genes involved in thyroid hormone synthesis and their critical regulators and of the TSH receptor as well as the uptake of iodide is attenuated in thyrocytes during mild ER stress. Down-regulation of NIS, TPO and TG during ER stress is likely the consequence of impaired TSH/TSHR signaling in concert with reduced expression of critical transcriptional regulators of these genes. PMID:29095946

Endoplasmic reticulum stress inhibits expression of genes involved in thyroid hormone synthesis and their key transcriptional regulators in FRTL-5 thyrocytes.

PubMed

Wen, Gaiping; Ringseis, Robert; Eder, Klaus

2017-01-01

Endoplasmic reticulum (ER) stress is characterized by the accumulation of misfolded proteins due to an impairment of ER quality control pathways leading to the activation of a defense system, called unfolded protein response (UPR). While thyrocytes are supposed to be highly susceptible to environmental conditions that cause ER stress due to the synthesis of large amounts of secretory proteins required for thyroid hormone synthesis, systematic investigations on the effect of ER stress on expression of key genes of thyroid hormone synthesis and their transcriptional regulators are lacking. Since the aim of the ER stress-induced UPR is to restore ER homeostasis and to facilitate cell survival through transient shutdown of ribosomal protein translation, we hypothesized that the expression of genes involved in thyroid hormone synthesis and their transcriptional regulators, all of which are not essential for cell survival, are down-regulated in thyrocytes during ER stress, while sterol regulatory element-binding proteins (SREBPs) are activated during ER stress in thyrocytes. Treatment of FRTL-5 thyrocytes with the ER stress inducer tunicamycin (TM) dose-dependently increased the mRNA and/or protein levels of known UPR target genes, stimulated phosphorylation of the ER stress sensor protein kinase RNA-like ER kinase (PERK) and of the PERK target protein eukaryotic initiation factor 2α (eIF2α) and caused splicing of the ER stress-sensitive transcription factor X-box binding protein (XBP-1) (P < 0.05). The mRNA levels and/or protein levels of genes involved in thyroid hormone synthesis, sodium/iodide symporter (NIS), thyroid peroxidase (TPO) and thyroglobulin (TG), their transcriptional regulators and thyrotropin (TSH) receptor and the uptake of Na125I were reduced at the highest concentration of TM tested (0.1 μg/mL; P < 0.05). Proteolytic activation of the SREBP-1c pathway was not observed in FRTL-5 cells treated with TM, whereas TM reduced proteolytic activation of the SREBP-2 pathway at 0.1 μg TM/mL (P < 0.05). In conclusion, the expression of key genes involved in thyroid hormone synthesis and their critical regulators and of the TSH receptor as well as the uptake of iodide is attenuated in thyrocytes during mild ER stress. Down-regulation of NIS, TPO and TG during ER stress is likely the consequence of impaired TSH/TSHR signaling in concert with reduced expression of critical transcriptional regulators of these genes.

Social Support and Occupational Stress among University Employees

ERIC Educational Resources Information Center

Cosio, Saharay E.

2011-01-01

Occupational stress creates a negative impact both at the microlevel (i.e., individuals) and at the macrolevel (i.e., organization). This study investigated the role of protective factors of social support and religiosity on occupational stress among university employees. The study used data collected from participants ( N = 72) in a private…

Evaluation of Stress Management Education: The University of Maryland Model.

ERIC Educational Resources Information Center

Allen, Roger J.

This study evaluated the efficacy of the undergraduate service program "Controlling Stress & Tension" at the University of Maryland in terms of improving the health status of participants across biomedical stress reactivity and psychometric variables. Six hundred fifty-three participants were compared to 264 control subjects for pre-…

Analysis of Acculturative Stress and Sociocultural Adaptation among International Students at a Non-Metropolitan University

ERIC Educational Resources Information Center

Mahmood, Hajara; Burke, Monica Galloway

2018-01-01

This quantitative descriptive study analyzed levels of acculturative stress and sociocultural adaptation among international students at a non-metropolitan university in the United States related to certain demographic characteristics. Surveys were used to measure international students' levels of acculturative stress and sociocultural adaptation,…

A Proteomics Approach to Discover Drought Tolerance Proteins in Wheat Pollen Grain at Meiosis Stage.

PubMed

Fotovat, Reza; Alikhani, Mehdi; Valizadeh, Mostafa; Mirzaei, Mehdi; Salekdeh, Ghasem H

2017-01-01

Plants reproductive phase, when grain yield and consequently farmers' investment is most in jeopardy, is considered as the most sensitive stage to drought stress. In this study, we aimed to explore the proteomic response of wheat anther at meiosis stage in a drought tolerant, Darab, and susceptible, Shiraz, wheat genotypes. Wheat plants were exposed to drought stress at meiosis stage for four days under controlled environmental conditions. Then, anthers from both genotypes were sampled, and their proteomes were examined via quantitative proteomics analysis. Our results demonstrated that short-term stress at meiosis stage reduced plant seed-setting compared to well-watered plants. This reduction was more pronounced in the susceptible genotype, Shiraz, by 51%, compared to the drought tolerant Darab by 14.3%. Proteome analysis revealed that 60 protein spots were drought responsive, out of which 44 were identified using a mass spectrometer. We observed a dramatic up-regulation of several heat shock proteins, as well as induction of Bet v I allergen family proteins, peroxiredoxin-5, and glutathione transferase with similar abundance in both genotypes. However, the abundance of proteins such as several stress response related proteins, including glutaredoxin, proteasome subunit alpha type 5, and ribosomal proteins showed a different response to drought stress in two genotypes. The differential abundance of proteins in two genotypes may suggest mechanisms by which tolerant genotype cope with drought stress. To the best of our knowledge, this is the first proteome analysis of plant reproductive tissue response to drought stress in wheat and could broaden our insight into plant adaptation to drought stress. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Sequestosome 1 (SQSTM1/p62) maintains protein folding capacity under endoplasmic reticulum stress in mouse hypothalamic organotypic culture.

PubMed

Tominaga, Takashi; Goto, Motomitsu; Onoue, Takeshi; Mizoguchi, Akira; Sugiyama, Mariko; Tsunekawa, Taku; Hagiwara, Daisuke; Morishita, Yoshiaki; Ito, Yoshihiro; Iwama, Shintaro; Suga, Hidetaka; Banno, Ryoichi; Arima, Hiroshi

2017-08-24

Sequestosome 1 (SQSTM1) also known as ubiquitin-binding protein p62 (p62) is a cargo protein involved in the degradation of misfolded proteins via selective autophagy. Disruption of autophagy and resulting accumulation of misfolded proteins in the endoplasmic reticulum (ER) leads to ER stress. ER stress is implicated in several neurodegenerative diseases and obesity. As knockout of p62 (p62KO) reportedly induces obesity in mice, we examined how p62 contributes to ER stress and the ensuing unfolded protein response (UPR) in hypothalamus using mouse organotypic cultures in the present study. Cultures from p62KO mice showed significantly reduced formation of LC3-GFP puncta, an index of autophagosome formation, in response to the chemical ER stressor thapsigargin compared to wild-type (WT) cultures. Hypothalamic cultures from p62KO mice exhibited higher basal expression of the UPR/ER stress markers CHOP mRNA and ATF4 mRNA than WT cultures. Thapsigargin enhanced CHOP, ATF4, and BiP mRNA as well as p-eIF2α protein expression in both WT and p62KO cultures, but all peak values were greater in p62KO cultures. A proteasome inhibitor increased p62 expression in WT cultures and upregulated the UPR/ER stress markers CHOP mRNA and ATF4 mRNA in both genotypes, but to a greater extent in p62KO cultures. Therefore, p62 deficiency disturbed autophagosome formation and enhanced both basal and chemically induced ER stress, suggesting that p62 serves to prevent ER stress in mouse hypothalamus by maintaining protein folding capacity. Copyright © 2017 Elsevier B.V. All rights reserved.

Therapeutic Massage Impacts Quality of Life for University Female Faculty in Teacher Education

ERIC Educational Resources Information Center

Sandstrom, Clarine

2009-01-01

Stress is a part of everyone's life. Depending on the level of stress, it may affect people's health and lives. Stress in the workplace may come from many different sources, however for the purpose of this study, the focus was on female faculty working in a Teacher Education program at a small north central, North Dakota university. Stress is…

Proteomic analyses reveal differences in cold acclimation mechanisms in freezing-tolerant and freezing-sensitive cultivars of alfalfa

PubMed Central

Chen, Jing; Han, Guiqing; Shang, Chen; Li, Jikai; Zhang, Hailing; Liu, Fengqi; Wang, Jianli; Liu, Huiying; Zhang, Yuexue

2015-01-01

Cold acclimation in alfalfa (Medicago sativa L.) plays a crucial role in cold tolerance to harsh winters. To examine the cold acclimation mechanisms in freezing-tolerant alfalfa (ZD) and freezing-sensitive alfalfa (W5), holoproteins, and low-abundance proteins (after the removal of RuBisCO) from leaves were extracted to analyze differences at the protein level. A total of 84 spots were selected, and 67 spots were identified. Of these, the abundance of 49 spots and 24 spots in ZD and W5, respectively, were altered during adaptation to chilling stress. Proteomic results revealed that proteins involved in photosynthesis, protein metabolism, energy metabolism, stress and redox and other proteins were mobilized in adaptation to chilling stress. In ZD, a greater number of changes were observed in proteins, and autologous metabolism and biosynthesis were slowed in response to chilling stress, thereby reducing consumption, allowing for homeostasis. The capability for protein folding and protein biosynthesis in W5 was enhanced, which allows protection against chilling stress. The ability to perceive low temperatures was more sensitive in freezing-tolerant alfalfa compared to freezing-sensitive alfalfa. This proteomics study provides new insights into the cold acclimation mechanism in alfalfa. PMID:25774161

Function of ABA in Stomatal Defense against Biotic and Drought Stresses

PubMed Central

Lim, Chae Woo; Baek, Woonhee; Jung, Jangho; Kim, Jung-Hyun; Lee, Sung Chul

2015-01-01

The plant hormone abscisic acid (ABA) regulates many key processes involved in plant development and adaptation to biotic and abiotic stresses. Under stress conditions, plants synthesize ABA in various organs and initiate defense mechanisms, such as the regulation of stomatal aperture and expression of defense-related genes conferring resistance to environmental stresses. The regulation of stomatal opening and closure is important to pathogen defense and control of transpirational water loss. Recent studies using a combination of approaches, including genetics, physiology, and molecular biology, have contributed considerably to our understanding of ABA signal transduction. A number of proteins associated with ABA signaling and responses—especially ABA receptors—have been identified. ABA signal transduction initiates signal perception by ABA receptors and transfer via downstream proteins, including protein kinases and phosphatases. In the present review, we focus on the function of ABA in stomatal defense against biotic and abiotic stresses, through analysis of each ABA signal component and the relationships of these components in the complex network of interactions. In particular, two ABA signal pathway models in response to biotic and abiotic stress were proposed, from stress signaling to stomatal closure, involving the pyrabactin resistance (PYR)/PYR-like (PYL) or regulatory component of ABA receptor (RCAR) family proteins, 2C-type protein phosphatases, and SnRK2-type protein kinases. PMID:26154766

Cold and Heat Stress Diversely Alter Both Cauliflower Respiration and Distinct Mitochondrial Proteins Including OXPHOS Components and Matrix Enzymes

PubMed Central

Rurek, Michał; Czołpińska, Magdalena; Pawłowski, Tomasz Andrzej; Krzesiński, Włodzimierz; Spiżewski, Tomasz

2018-01-01

Complex proteomic and physiological approaches for studying cold and heat stress responses in plant mitochondria are still limited. Variations in the mitochondrial proteome of cauliflower (Brassica oleracea var. botrytis) curds after cold and heat and after stress recovery were assayed by two-dimensional polyacrylamide gel electrophoresis (2D PAGE) in relation to mRNA abundance and respiratory parameters. Quantitative analysis of the mitochondrial proteome revealed numerous stress-affected protein spots. In cold, major downregulations in the level of photorespiratory enzymes, porine isoforms, oxidative phosphorylation (OXPHOS) and some low-abundant proteins were observed. In contrast, carbohydrate metabolism enzymes, heat-shock proteins, translation, protein import, and OXPHOS components were involved in heat response and recovery. Several transcriptomic and metabolic regulation mechanisms are also suggested. Cauliflower plants appeared less susceptible to heat; closed stomata in heat stress resulted in moderate photosynthetic, but only minor respiratory impairments, however, photosystem II performance was unaffected. Decreased photorespiration corresponded with proteomic alterations in cold. Our results show that cold and heat stress not only operate in diverse modes (exemplified by cold-specific accumulation of some heat shock proteins), but exert some associations at molecular and physiological levels. This implies a more complex model of action of investigated stresses on plant mitochondria. PMID:29547512

Protein synthesis inhibition activity by strawberry tissue protein extracts during plant life cycle and under biotic and abiotic stresses.

PubMed

Polito, Letizia; Bortolotti, Massimo; Mercatelli, Daniele; Mancuso, Rossella; Baruzzi, Gianluca; Faedi, Walther; Bolognesi, Andrea

2013-07-25

Ribosome-inactivating proteins (RIPs), enzymes that are widely distributed in the plant kingdom, inhibit protein synthesis by depurinating rRNA and many other polynucleotidic substrates. Although RIPs show antiviral, antifungal, and insecticidal activities, their biological and physiological roles are not completely understood. Additionally, it has been described that RIP expression is augmented under stressful conditions. In this study, we evaluated protein synthesis inhibition activity in partially purified basic proteins (hereafter referred to as RIP activity) from tissue extracts of Fragaria × ananassa (strawberry) cultivars with low (Dora) and high (Record) tolerance to root pathogens and fructification stress. Association between the presence of RIP activity and the crop management (organic or integrated soil), growth stage (quiescence, flowering, and fructification), and exogenous stress (drought) were investigated. RIP activity was found in every tissue tested (roots, rhizomes, leaves, buds, flowers, and fruits) and under each tested condition. However, significant differences in RIP distribution were observed depending on the soil and growth stage, and an increase in RIP activity was found in the leaves of drought-stressed plants. These results suggest that RIP expression and activity could represent a response mechanism against biotic and abiotic stresses and could be a useful tool in selecting stress-resistant strawberry genotypes.

Adaptation to ER Stress Is Mediated by Differential Stabilities of Pro-Survival and Pro-Apoptotic mRNAs and Proteins

PubMed Central

Rutkowski, D. Thomas; Arnold, Stacey M; Miller, Corey N; Wu, Jun; Li, Jack; Gunnison, Kathryn M; Mori, Kazutoshi; Sadighi Akha, Amir A.; Raden, David; Kaufman, Randal J

2006-01-01

The accumulation of unfolded proteins in the endoplasmic reticulum (ER) activates a signaling cascade known as the unfolded protein response (UPR). Although activation of the UPR is well described, there is little sense of how the response, which initiates both apoptotic and adaptive pathways, can selectively allow for adaptation. Here we describe the reconstitution of an adaptive ER stress response in a cell culture system. Monitoring the activation and maintenance of representative UPR gene expression pathways that facilitate either adaptation or apoptosis, we demonstrate that mild ER stress activates all UPR sensors. However, survival is favored during mild stress as a consequence of the intrinsic instabilities of mRNAs and proteins that promote apoptosis compared to those that facilitate protein folding and adaptation. As a consequence, the expression of apoptotic proteins is short-lived as cells adapt to stress. We provide evidence that the selective persistence of ER chaperone expression is also applicable to at least one instance of genetic ER stress. This work provides new insight into how a stress response pathway can be structured to allow cells to avert death as they adapt. It underscores the contribution of posttranscriptional and posttranslational mechanisms in influencing this outcome. PMID:17090218

Effect of acute heat stress on plant nutrient metabolism proteins

USDA-ARS?s Scientific Manuscript database

Abrupt heating decreased the levels (per unit total root protein) of all but one of the nutrient metabolism proteins examined, and for most of the proteins, effects were greater for severe vs. moderate heat stress. For many of the nutrient metabolism proteins, initial effects of heat (1 d) were r...

A role for SR proteins in plant stress responses.

PubMed

Duque, Paula

2011-01-01

Members of the SR (serine/arginine-rich) protein gene family are key players in the regulation of alternative splicing, an important means of generating proteome diversity and regulating gene expression. In plants, marked changes in alternative splicing are induced by a wide variety of abiotic stresses, suggesting a role for this highly versatile gene regulation mechanism in the response to environmental cues. In support of this notion, the expression of plant SR proteins is stress-regulated at multiple levels, with environmental signals controlling their own alternative splicing patterns, phosphorylation status and subcellular distribution. Most importantly, functional links between these RNA-binding proteins and plant stress tolerance are beginning to emerge, including a role in the regulation of abscisic acid (ABA) signaling. Future identification of the physiological mRNA targets of plant SR proteins holds much promise for the elucidation of the molecular mechanisms underlying their role in the response to abiotic stress.

A role for SR proteins in plant stress responses

PubMed Central

2011-01-01

Members of the SR (serine/arginine-rich) protein gene family are key players in the regulation of alternative splicing, an important means of generating proteome diversity and regulating gene expression. In plants, marked changes in alternative splicing are induced by a wide variety of abiotic stresses, suggesting a role for this highly versatile gene regulation mechanism in the response to environmental cues. In support of this notion, the expression of plant SR proteins is stress-regulated at multiple levels, with environmental signals controlling their own alternative splicing patterns, phosphorylation status and subcellular distribution. Most importantly, functional links between these RNA-binding proteins and plant stress tolerance are beginning to emerge, including a role in the regulation of abscisic acid (ABA) signaling. Future identification of the physiological mRNA targets of plant SR proteins holds much promise for the elucidation of the molecular mechanisms underlying their role in the response to abiotic stress. PMID:21258207

Abiotic stress responses in plants: roles of calmodulin-regulated proteins.

PubMed

Virdi, Amardeep S; Singh, Supreet; Singh, Prabhjeet

2015-01-01

Intracellular changes in calcium ions (Ca(2+)) in response to different biotic and abiotic stimuli are detected by various sensor proteins in the plant cell. Calmodulin (CaM) is one of the most extensively studied Ca(2+)-sensing proteins and has been shown to be involved in transduction of Ca(2+) signals. After interacting with Ca(2+), CaM undergoes conformational change and influences the activities of a diverse range of CaM-binding proteins. A number of CaM-binding proteins have also been implicated in stress responses in plants, highlighting the central role played by CaM in adaptation to adverse environmental conditions. Stress adaptation in plants is a highly complex and multigenic response. Identification and characterization of CaM-modulated proteins in relation to different abiotic stresses could, therefore, prove to be essential for a deeper understanding of the molecular mechanisms involved in abiotic stress tolerance in plants. Various studies have revealed involvement of CaM in regulation of metal ions uptake, generation of reactive oxygen species and modulation of transcription factors such as CAMTA3, GTL1, and WRKY39. Activities of several kinases and phosphatases have also been shown to be modulated by CaM, thus providing further versatility to stress-associated signal transduction pathways. The results obtained from contemporary studies are consistent with the proposed role of CaM as an integrator of different stress signaling pathways, which allows plants to maintain homeostasis between different cellular processes. In this review, we have attempted to present the current state of understanding of the role of CaM in modulating different stress-regulated proteins and its implications in augmenting abiotic stress tolerance in plants.

Abiotic stress responses in plants: roles of calmodulin-regulated proteins

PubMed Central

Virdi, Amardeep S.; Singh, Supreet; Singh, Prabhjeet

2015-01-01

Intracellular changes in calcium ions (Ca2+) in response to different biotic and abiotic stimuli are detected by various sensor proteins in the plant cell. Calmodulin (CaM) is one of the most extensively studied Ca2+-sensing proteins and has been shown to be involved in transduction of Ca2+ signals. After interacting with Ca2+, CaM undergoes conformational change and influences the activities of a diverse range of CaM-binding proteins. A number of CaM-binding proteins have also been implicated in stress responses in plants, highlighting the central role played by CaM in adaptation to adverse environmental conditions. Stress adaptation in plants is a highly complex and multigenic response. Identification and characterization of CaM-modulated proteins in relation to different abiotic stresses could, therefore, prove to be essential for a deeper understanding of the molecular mechanisms involved in abiotic stress tolerance in plants. Various studies have revealed involvement of CaM in regulation of metal ions uptake, generation of reactive oxygen species and modulation of transcription factors such as CAMTA3, GTL1, and WRKY39. Activities of several kinases and phosphatases have also been shown to be modulated by CaM, thus providing further versatility to stress-associated signal transduction pathways. The results obtained from contemporary studies are consistent with the proposed role of CaM as an integrator of different stress signaling pathways, which allows plants to maintain homeostasis between different cellular processes. In this review, we have attempted to present the current state of understanding of the role of CaM in modulating different stress-regulated proteins and its implications in augmenting abiotic stress tolerance in plants. PMID:26528296

Salt stress induces changes in the proteomic profile of micropropagated sugarcane shoots

PubMed Central

Reis, Ricardo S.; Heringer, Angelo S.; Rangel, Patricia L.; Santa-Catarina, Claudete; Grativol, Clícia; Veiga, Carlos F. M.; Souza-Filho, Gonçalo A.

2017-01-01

Salt stress is one of the most common stresses in agricultural regions worldwide. In particular, sugarcane is affected by salt stress conditions, and no sugarcane cultivar presently show high productivity accompanied by a tolerance to salt stress. Proteomic analysis allows elucidation of the important pathways involved in responses to various abiotic stresses at the biochemical and molecular levels. Thus, this study aimed to analyse the proteomic effects of salt stress in micropropagated shoots of two sugarcane cultivars (CB38-22 and RB855536) using a label-free proteomic approach. The mass spectrometry proteomics data are available via ProteomeXchange with identifier PXD006075. The RB855536 cultivar is more tolerant to salt stress than CB38-22. A quantitative label-free shotgun proteomic analysis identified 1172 non-redundant proteins, and 1160 of these were observed in both cultivars in the presence or absence of NaCl. Compared with CB38-22, the RB855536 cultivar showed a greater abundance of proteins involved in non-enzymatic antioxidant mechanisms, ion transport, and photosynthesis. Some proteins, such as calcium-dependent protein kinase, photosystem I, phospholipase D, and glyceraldehyde-3-phosphate dehydrogenase, were more abundant in the RB855536 cultivar under salt stress. Our results provide new insights into the response of sugarcane to salt stress, and the changes in the abundance of these proteins might be important for the acquisition of ionic and osmotic homeostasis during exposure to salt stress. PMID:28419154

A Molecular Web: Endoplasmic Reticulum Stress, Inflammation, and Oxidative Stress

PubMed Central

Chaudhari, Namrata; Talwar, Priti; Parimisetty, Avinash; Lefebvre d’Hellencourt, Christian; Ravanan, Palaniyandi

2014-01-01

Execution of fundamental cellular functions demands regulated protein folding homeostasis. Endoplasmic reticulum (ER) is an active organelle existing to implement this function by folding and modifying secretory and membrane proteins. Loss of protein folding homeostasis is central to various diseases and budding evidences suggest ER stress as being a major contributor in the development or pathology of a diseased state besides other cellular stresses. The trigger for diseases may be diverse but, inflammation and/or ER stress may be basic mechanisms increasing the severity or complicating the condition of the disease. Chronic ER stress and activation of the unfolded-protein response (UPR) through endogenous or exogenous insults may result in impaired calcium and redox homeostasis, oxidative stress via protein overload thereby also influencing vital mitochondrial functions. Calcium released from the ER augments the production of mitochondrial Reactive Oxygen Species (ROS). Toxic accumulation of ROS within ER and mitochondria disturbs fundamental organelle functions. Sustained ER stress is known to potentially elicit inflammatory responses via UPR pathways. Additionally, ROS generated through inflammation or mitochondrial dysfunction could accelerate ER malfunction. Dysfunctional UPR pathways have been associated with a wide range of diseases including several neurodegenerative diseases, stroke, metabolic disorders, cancer, inflammatory disease, diabetes mellitus, cardiovascular disease, and others. In this review, we have discussed the UPR signaling pathways, and networking between ER stress-induced inflammatory pathways, oxidative stress, and mitochondrial signaling events, which further induce or exacerbate ER stress. PMID:25120434

Chronic Stress in Young German Adults: Who Is Affected? A Prospective Cohort Study.

PubMed

Herrera, Ronald; Berger, Ursula; Genuneit, Jon; Gerlich, Jessica; Nowak, Dennis; Schlotz, Wolff; Vogelberg, Christian; von Mutius, Erika; Weinmayr, Gudrun; Windstetter, Doris; Weigl, Matthias; Radon, Katja

2017-10-31

We aimed to prospectively assess changes in chronic stress among young adults transitioning from high school to university or working life. A population-based cohort in Munich and Dresden (Germany) was followed from age 16-18 (2002-2003) to age 20-23 (2007-2009) ( n = 1688). Using the Trier Inventory for the Assessment of Chronic Stress, two dimensions of stress at university or work were assessed: work overload and work discontent. In the multiple ordinal generalized estimating equations, socio-demographics, stress outside the workplace, and job history were additionally considered. At follow-up, 52% of the population were university students. Work overload increased statistically significantly from first to second follow-up, while work discontent remained constant at the population level. Students, compared to employees, reported a larger increase in work overload (adjusted odds ratio (OR): 1.33; 95% confidence interval (95% CI): 1.07, 1.67), while work discontent did not differ between the groups. In conclusion, work overload increases when young adults transition from school to university/job life, with university students experiencing the largest increase.

Chronic Stress in Young German Adults: Who Is Affected? A Prospective Cohort Study

PubMed Central

Herrera, Ronald; Berger, Ursula; Gerlich, Jessica; Nowak, Dennis; Schlotz, Wolff; Vogelberg, Christian; von Mutius, Erika; Weinmayr, Gudrun; Windstetter, Doris; Weigl, Matthias; Radon, Katja

2017-01-01

We aimed to prospectively assess changes in chronic stress among young adults transitioning from high school to university or working life. A population-based cohort in Munich and Dresden (Germany) was followed from age 16–18 (2002–2003) to age 20–23 (2007–2009) (n = 1688). Using the Trier Inventory for the Assessment of Chronic Stress, two dimensions of stress at university or work were assessed: work overload and work discontent. In the multiple ordinal generalized estimating equations, socio-demographics, stress outside the workplace, and job history were additionally considered. At follow-up, 52% of the population were university students. Work overload increased statistically significantly from first to second follow-up, while work discontent remained constant at the population level. Students, compared to employees, reported a larger increase in work overload (adjusted odds ratio (OR): 1.33; 95% confidence interval (95% CI): 1.07, 1.67), while work discontent did not differ between the groups. In conclusion, work overload increases when young adults transition from school to university/job life, with university students experiencing the largest increase. PMID:29088088

Integrative proteome analysis of Brachypodium distachyon roots and leaves reveals a synergetic responsive network under H2O2 stress.

PubMed

Bian, Yan-Wei; Lv, Dong-Wen; Cheng, Zhi-Wei; Gu, Ai-Qin; Cao, Hui; Yan, Yue-Ming

2015-10-14

The plant oxidative stress response is vital for defense against various abiotic and biotic stresses. In this study, ultrastructural changes and the proteomic response to H2O2 stress in roots and leaves of the model plant Brachypodium distachyon were studied. Transmission electron microscopy (TEM) showed that the ultrastructural damage in roots was more serious than in leaves. Particularly, the ultrastructures of organelles and the nucleus in root tip cells were damaged, leading to the inhibition of normal biological activities of roots, which then spread throughout the plant. Based on two-dimensional electrophoresis (2-DE) and MALDI-TOF/TOF-MS, 84 and 53 differentially accumulated protein (DAP) spots representing 75 and 45 unique proteins responsive to H2O2 stress in roots and leaves, respectively, were identified. These protein species were mainly involved in signal transduction, energy metabolism, redox homeostasis/stress defense, protein folding/degradation, and cell wall/cell structure. Interestingly, two 14-3-3 proteins (GF14-B and GF14-D) were identified as DAPs in both roots and leaves. Protein-protein interaction (PPI) analysis revealed a synergetic H2O2-responsive network. Copyright © 2015 Elsevier B.V. All rights reserved.

Cellular stress induces cytoplasmic RNA granules in fission yeast.

PubMed

Nilsson, Daniel; Sunnerhagen, Per

2011-01-01

Severe stress causes plant and animal cells to form large cytoplasmic granules containing RNA and proteins. Here, we demonstrate the existence of stress-induced cytoplasmic RNA granules in Schizosaccharomyces pombe. Homologs to several known protein components of mammalian processing bodies and stress granules are found in fission yeast RNA granules. In contrast to mammalian cells, poly(A)-binding protein (Pabp) colocalizes in stress-induced granules with decapping protein. After glucose deprivation, protein kinase A (PKA) is required for accumulation of Pabp-positive granules and translational down-regulation. This is the first demonstration of a role for PKA in RNA granule formation. In mammals, the translation initiation protein eIF2α is a key regulator of formation of granules containing poly(A)-binding protein. In S. pombe, nonphosphorylatable eIF2α does not block but delays granule formation and subsequent clearance after exposure to hyperosmosis. At least two separate pathways in S. pombe appear to regulate stress-induced granules: pka1 mutants are fully proficient to form granules after hyperosmotic shock; conversely, eIF2α does not affect granule formation in glucose starvation. Further, we demonstrate a Pka1-dependent link between calcium perturbation and RNA granules, which has not been described earlier in any organism.

Ribosomal protein L19 overexpression activates the unfolded protein response and sensitizes MCF7 breast cancer cells to endoplasmic reticulum stress-induced cell death.

PubMed

Hong, Mina; Kim, HyungRyong; Kim, Inki

2014-07-18

Although first identified for their roles in protein synthesis, certain ribosomal proteins exert pleiotropic physiological functions in the cell. Ribosomal protein L19 is overexpressed in breast cancer cells by amplification and copy number variation. In this study, we examined the novel pro-apoptotic role of ribosomal protein L19 in the breast cancer cell line MCF7. Overexpression of RPL19 sensitized MCF7 cells to endoplasmic reticulum stress-induced cell death. RPL19 overexpression itself was not cytotoxic; however, cell death induction was enhanced when RPL19 overexpressing cells were incubated with endoplasmic reticulum stress-inducing agents, and this sensitizing effect was specific to MCF7 cells. Examination of the cell signaling pathways that mediate the unfolded protein response (UPR) revealed that overexpression of RPL19 induced pre-activation of the UPR, including phosphorylation of pERK-like ER kinase (PERK), phosphorylation of eukaryotic translation initiation factor 2 alpha (eIF2α), and activation of p38 MAPK-associated stress signaling. Our findings suggest that upregulation of RPL19 induces ER stress, resulting in increased sensitivity to ER stress and enhanced cell death in MCF7 breast cancer cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Molecular analysis of Hsp70 mechanisms in plants and their function in response to stress.

PubMed

Usman, Magaji G; Rafii, Mohd Y; Martini, Mohammad Y; Yusuff, Oladosu A; Ismail, Mohd R; Miah, Gous

2017-04-01

Studying the strategies of improving abiotic stress tolerance is quite imperative and research under this field will increase our understanding of response mechanisms to abiotic stress such as heat. The Hsp70 is an essential regulator of protein having the tendency to maintain internal cell stability like proper folding protein and breakdown of unfolded proteins. Hsp70 holds together protein substrates to help in movement, regulation, and prevent aggregation under physical and or chemical pressure. However, this review reports the molecular mechanism of heat shock protein 70 kDa (Hsp70) action and its structural and functional analysis, research progress on the interaction of Hsp70 with other proteins and their interaction mechanisms as well as the involvement of Hsp70 in abiotic stress responses as an adaptive defense mechanism.

Salicylic acid interferes with GFP fluorescence in vivo.

PubMed

de Jonge, Jennifer; Hofius, Daniel; Hennig, Lars

2017-03-01

Fluorescent proteins have become essential tools for cell biologists. They are routinely used by plant biologists for protein and promoter fusions to infer protein localization, tissue-specific expression and protein abundance. When studying the effects of biotic stress on chromatin, we unexpectedly observed a decrease in GFP signal intensity upon salicylic acid (SA) treatment in Arabidopsis lines expressing histone H1-GFP fusions. This GFP signal decrease was dependent on SA concentration. The effect was not specific to the linker histone H1-GFP fusion but was also observed for the nucleosomal histone H2A-GFP fusion. This result prompted us to investigate a collection of fusion proteins, which included different promoters, subcellular localizations and fluorophores. In all cases, fluorescence signals declined strongly or disappeared after SA application. No changes were detected in GFP-fusion protein abundance when fluorescence signals were lost indicating that SA does not interfere with protein stability but GFP fluorescence. In vitro experiments showed that SA caused GFP fluorescence reduction only in vivo but not in vitro, suggesting that SA requires cellular components to cause fluorescence reduction. Together, we conclude that SA can interfere with the fluorescence of various GFP-derived reporter constructs in vivo. Assays that measure relocation or turnover of GFP-tagged proteins upon SA treatment should therefore be evaluated with caution. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Proteomic analysis on roots of Oenothera glazioviana under copper-stress conditions.

PubMed

Wang, Chong; Wang, Jie; Wang, Xiao; Xia, Yan; Chen, Chen; Shen, Zhenguo; Chen, Yahua

2017-09-06

Proteomic studies were performed to identify proteins involved in the response of Oenothera glazioviana seedlings under Cu stress. Exposure of 28-d-old seedlings to 50 μM CuSO4 for 3 d led to inhibition of shoot and root growth as well as a considerable increase in the level of lipid peroxidation in the roots. Cu absorbed by O. glazioviana accumulated more easily in the root than in the shoot. Label-free proteomic analysis indicated 58 differentially abundant proteins (DAPs) of the total 3,149 proteins in the roots of O. glazioviana seedlings, of which 36 were upregulated and 22 were downregulated under Cu stress conditions. Gene Ontology analysis showed that most of the identified proteins could be annotated to signal transduction, detoxification, stress defence, carbohydrate, energy, and protein metabolism, development, and oxidoreduction. We also retrieved 13 proteins from the enriched Kyoto Encyclopaedia of Genes and Genomes and the protein-protein interaction databases related to various pathways, including the citric acid (CA) cycle. Application of exogenous CA to O. glazioviana seedlings exposed to Cu alleviated the stress symptoms. Overall, this study provided new insights into the molecular mechanisms of plant response to Cu at the protein level in relation to soil properties.

Mycobacterium tuberculosis universal stress protein Rv2623 interacts with the putative ATP binding cassette (ABC) transporter Rv1747 to regulate mycobacterial growth.

PubMed

Glass, Lisa N; Swapna, Ganduri; Chavadi, Sivagami Sundaram; Tufariello, JoAnn M; Mi, Kaixia; Drumm, Joshua E; Lam, TuKiet T; Zhu, Guofeng; Zhan, Chenyang; Vilchéze, Catherine; Arcos, Jesus; Chen, Yong; Bi, Lijun; Mehta, Simren; Porcelli, Steven A; Almo, Steve C; Yeh, Syun-Ru; Jacobs, William R; Torrelles, Jordi B; Chan, John

2017-07-01

We have previously shown that the Mycobacterium tuberculosis universal stress protein Rv2623 regulates mycobacterial growth and may be required for the establishment of tuberculous persistence. Here, yeast two-hybrid and affinity chromatography experiments have demonstrated that Rv2623 interacts with one of the two forkhead-associated domains (FHA I) of Rv1747, a putative ATP-binding cassette transporter annotated to export lipooligosaccharides. FHA domains are signaling protein modules that mediate protein-protein interactions to modulate a wide variety of biological processes via binding to conserved phosphorylated threonine (pT)-containing oligopeptides of the interactors. Biochemical, immunochemical and mass spectrometric studies have shown that Rv2623 harbors pT and specifically identified threonine 237 as a phosphorylated residue. Relative to wild-type Rv2623 (Rv2623WT), a mutant protein in which T237 has been replaced with a non-phosphorylatable alanine (Rv2623T237A) exhibits decreased interaction with the Rv1747 FHA I domain and diminished growth-regulatory capacity. Interestingly, compared to WT bacilli, an M. tuberculosis Rv2623 null mutant (ΔRv2623) displays enhanced expression of phosphatidyl-myo-inositol mannosides (PIMs), while the ΔRv1747 mutant expresses decreased levels of PIMs. Animal studies have previously shown that ΔRv2623 is hypervirulent, while ΔRv1747 is growth-attenuated. Collectively, these data have provided evidence that Rv2623 interacts with Rv1747 to regulate mycobacterial growth; and this interaction is mediated via the recognition of the conserved Rv2623 pT237-containing FHA-binding motif by the Rv1747 FHA I domain. The divergent aberrant PIM profiles and the opposing in vivo growth phenotypes of ΔRv2623 and ΔRv1747, together with the annotated lipooligosaccharide exporter function of Rv1747, suggest that Rv2623 interacts with Rv1747 to modulate mycobacterial growth by negatively regulating the activity of Rv1747; and that Rv1747 might function as a transporter of PIMs. Because these glycolipids are major mycobacterial cell envelope components that can impact on the immune response, our findings raise the possibility that Rv2623 may regulate bacterial growth, virulence, and entry into persistence, at least in part, by modulating the levels of bacillary PIM expression, perhaps through negatively regulating the Rv1747-dependent export of the immunomodulatory PIMs to alter host-pathogen interaction, thereby influencing the fate of M. tuberculosis in vivo.

Activation of autophagy by unfolded proteins during endoplasmic reticulum stress.

PubMed

Yang, Xiaochen; Srivastava, Renu; Howell, Stephen H; Bassham, Diane C

2016-01-01

Endoplasmic reticulum stress is defined as the accumulation of unfolded proteins in the endoplasmic reticulum, and is caused by conditions such as heat or agents that cause endoplasmic reticulum stress, including tunicamycin and dithiothreitol. Autophagy, a major pathway for degradation of macromolecules in the vacuole, is activated by these stress agents in a manner dependent on inositol-requiring enzyme 1b (IRE1b), and delivers endoplasmic reticulum fragments to the vacuole for degradation. In this study, we examined the mechanism for activation of autophagy during endoplasmic reticulum stress in Arabidopsis thaliana. The chemical chaperones sodium 4-phenylbutyrate and tauroursodeoxycholic acid were found to reduce tunicamycin- or dithiothreitol-induced autophagy, but not autophagy caused by unrelated stresses. Similarly, over-expression of BINDING IMMUNOGLOBULIN PROTEIN (BIP), encoding a heat shock protein 70 (HSP70) molecular chaperone, reduced autophagy. Autophagy activated by heat stress was also found to be partially dependent on IRE1b and to be inhibited by sodium 4-phenylbutyrate, suggesting that heat-induced autophagy is due to accumulation of unfolded proteins in the endoplasmic reticulum. Expression in Arabidopsis of the misfolded protein mimics zeolin or a mutated form of carboxypeptidase Y (CPY*) also induced autophagy in an IRE1b-dependent manner. Moreover, zeolin and CPY* partially co-localized with the autophagic body marker GFP-ATG8e, indicating delivery to the vacuole by autophagy. We conclude that accumulation of unfolded proteins in the endoplasmic reticulum is a trigger for autophagy under conditions that cause endoplasmic reticulum stress. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

Protein Contribution to Plant Salinity Response and Tolerance Acquisition

PubMed Central

Kosová, Klára; Prášil, Ilja T.; Vítámvás, Pavel

2013-01-01

The review is focused on plant proteome response to salinity with respect to physiological aspects of plant salt stress response. The attention is paid to both osmotic and ionic effects of salinity stress on plants with respect to several protein functional groups. Therefore, the role of individual proteins involved in signalling, changes in gene expression, protein biosynthesis and degradation and the resulting changes in protein relative abundance in proteins involved in energy metabolism, redox metabolism, stressand defence-related proteins, osmolyte metabolism, phytohormone, lipid and secondary metabolism, mechanical stress-related proteins as well as protein posttranslational modifications are discussed. Differences between salt-sensitive (glycophytes) and salt-tolerant (halophytes) plants are analysed with respect to differential salinity tolerance. In conclusion, contribution of proteomic studies to understanding plant salinity tolerance is summarised and discussed. PMID:23531537

Analysis of initial changes in the proteins of soybean root tip under flooding stress using gel-free and gel-based proteomic techniques.

PubMed

Yin, Xiaojian; Sakata, Katsumi; Nanjo, Yohei; Komatsu, Setsuko

2014-06-25

Flooding has a severe negative effect on soybean cultivation in the early stages of growth. To obtain a better understanding of the response mechanisms of soybean to flooding stress, initial changes in root tip proteins under flooding were analyzed using two proteomic techniques. Two-day-old soybeans were treated with flooding for 3, 6, 12, and 24h. The weight of soybeans increased during the first 3h of flooding, but root elongation was not observed. Using gel-based and gel-free proteomic techniques, 115 proteins were identified in root tips, of which 9 proteins were commonly detected by both methods. The 71 proteins identified by the gel-free proteomics were analyzed by a hierarchical clustering method based on induction levels during the flooding, and the proteins were divided into 5 clusters. Additional interaction analysis of the proteins revealed that ten proteins belonging to cluster I formed the center of a protein interaction network. mRNA expression analysis of these ten proteins showed that citrate lyase and heat shock protein 70 were down-regulated, whereas calreticulin was up-regulated in initial phase of flooding. These results suggest that flooding stress to soybean induces calcium-related signal transduction, which might play important roles in the early responses to flooding. Flooding has a severe negative effect on soybean cultivation, particularly in the early stages of growth. To better understand the response mechanisms of soybean to the early stages of flooding stress, two proteomic techniques were used. Two-day-old soybeans were treated without or with flooding for 3, 6, 12, and 24h. The fresh weight of soybeans increased during the first 3h of flooding stress, but the growth then slowed and no root elongation was observed. Using gel-based and gel-free proteomic techniques, 115 proteins were identified in root tips, of which 9 proteins were commonly detected by both methods. The 71 proteins identified by the gel-free proteomics were analyzed by a hierarchical clustering method based on induction levels during the flooding stress, and 5 protein clusters were recognized. Protein interaction analysis revealed that ten proteins belonging to cluster I formed the center of a protein interaction network. mRNA expression analysis of these ten proteins showed that citrate lyase and heat shock protein 70 were down-regulated in response to flooding stress, whereas calreticulin was up-regulated. These results suggest that flooding stress to soybean induces calcium-related signal transduction, which might play important roles in the early responses to flooding. Copyright © 2014 Elsevier B.V. All rights reserved.

Proteomic analysis of salt stress and recovery in leaves of Vigna unguiculata cultivars differing in salt tolerance.

PubMed

de Abreu, Carlos Eduardo Braga; Araújo, Gyedre dos Santos; Monteiro-Moreira, Ana Cristina de Oliveira; Costa, José Hélio; Leite, Hugo de Brito; Moreno, Frederico Bruno Mendes Batista; Prisco, José Tarquinio; Gomes-Filho, Enéas

2014-08-01

Cowpea cultivars differing in salt tolerance reveal differences in protein profiles and adopt different strategies to overcome salt stress. Salt-tolerant cultivar shows induction of proteins related to photosynthesis and energy metabolism. Salinity is a major abiotic stress affecting plant cultivation and productivity. The objective of this study was to examine differential proteomic responses to salt stress in leaves of the cowpea cultivars Pitiúba (salt tolerant) and TVu 2331 (salt sensitive). Plants of both cultivars were subjected to salt stress (75 mM NaCl) followed by a recovery period of 5 days. Proteins extracted from leaves of both cultivars were analyzed by two-dimensional electrophoresis (2-DE) under salt stress and after recovery. In total, 22 proteins differentially regulated by both salt and recovery were identified by LC-ESI-MS/MS. Our current proteome data revealed that cowpea cultivars adopted different strategies to overcome salt stress. For the salt-tolerant cultivar (Pitiúba), increase in abundance of proteins involved in photosynthesis and energy metabolism, such as rubisco activase, ribulose-5-phosphate kinase (Ru5PK) (EC 2.7.1.19), glycine decarboxylase (EC 1.4.4.2) and oxygen-evolving enhancer (OEE) protein 2, was observed. However, these vital metabolic processes were more profoundly affected in salt-sensitive cultivar (TVu), as indicated by the down-regulation of OEE protein 1, Mn-stabilizing protein-II, carbonic anhydrase (EC 4.2.1.1) and Rubisco (EC 4.1.1.39), leading to energy reduction and a decline in plant growth. Other proteins differentially regulated in both cultivars corresponded to different physiological responses. Overall, our results provide information that could lead to a better understanding of the molecular basis of salt tolerance and sensitivity in cowpea plants.

Persulfidation proteome reveals the regulation of protein function by hydrogen sulfide in diverse biological processes in Arabidopsis.

PubMed

Aroca, Angeles; Benito, Juan M; Gotor, Cecilia; Romero, Luis C

2017-10-13

Hydrogen sulfide-mediated signaling pathways regulate many physiological and pathophysiological processes in mammalian and plant systems. The molecular mechanism by which hydrogen sulfide exerts its action involves the post-translational modification of cysteine residues to form a persulfidated thiol motif, a process called protein persulfidation. We have developed a comparative and quantitative proteomic analysis approach for the detection of endogenous persulfidated proteins in wild-type Arabidopsis and L-CYSTEINE DESULFHYDRASE 1 mutant leaves using the tag-switch method. The 2015 identified persulfidated proteins were isolated from plants grown under controlled conditions, and therefore, at least 5% of the entire Arabidopsis proteome may undergo persulfidation under baseline conditions. Bioinformatic analysis revealed that persulfidated cysteines participate in a wide range of biological functions, regulating important processes such as carbon metabolism, plant responses to abiotic and biotic stresses, plant growth and development, and RNA translation. Quantitative analysis in both genetic backgrounds reveals that protein persulfidation is mainly involved in primary metabolic pathways such as the tricarboxylic acid cycle, glycolysis, and the Calvin cycle, suggesting that this protein modification is a new regulatory component in these pathways. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Redox-regulated chaperones.

PubMed

Kumsta, Caroline; Jakob, Ursula

2009-06-09

Redox regulation of stress proteins, such as molecular chaperones, guarantees an immediate response to oxidative stress conditions. This review focuses on the two major classes of redox-regulated chaperones, Hsp33 in bacteria and typical 2-Cys peroxiredoxins in eukaryotes. Both proteins employ redox-sensitive cysteines, whose oxidation status directly controls their affinity for unfolding proteins and therefore their chaperone function. We will first discuss Hsp33, whose oxidative stress-induced disulfide bond formation triggers the partial unfolding of the chaperone, which, in turn, leads to the exposure of a high-affinity binding site for unfolded proteins. This rapid mode of activation makes Hsp33 essential for protecting bacteria against severe oxidative stress conditions, such as hypochlorite (i.e., bleach) treatment, which leads to widespread protein unfolding and aggregation. We will compare Hsp33 to the highly abundant eukaryotic typical 2-Cys peroxiredoxin, whose oxidative stress-induced sulfinic acid formation turns the peroxidase into a molecular chaperone in vitro and presumably in vivo. These examples illustrate how proteins use reversible cysteine modifications to rapidly adjust to oxidative stress conditions and demonstrate that redox regulation plays a vital role in protecting organisms against reactive oxygen species-mediated cell death.

Proteomic insights into the protective mechanisms of an in vitro oxidative stress model of early stage Parkinson's disease.

PubMed

Bauereis, Brian; Haskins, William E; Lebaron, Richard G; Renthal, Robert

2011-01-13

Previous studies in Parkinson's disease (PD) models suggest that early events along the path to neurodegeneration involve activation of the ubiquitin-proteasome system (UPS), endoplasmic reticulum-associated degradation (ERAD), and the unfolded protein response (UPR) pathways, in both the sporadic and familial forms of the disease, and thus ER stress may be a common feature. Furthermore, impairments in protein degradation have been linked to oxidative stress as well as pathways associated with ER stress. We hypothesize that oxidative stress is a primary initiator in a multi-factorial cascade driving dopaminergic (DA) neurons towards death in the early stages of the disease. We now report results from proteomic analysis of a rotenone-induced oxidative stress model of PD in the human neuroblastoma cell line, SH-SY5Y. Cells were exposed to sub-micromolar concentrations of rotenone for 48h prior to whole cell protein extraction and shotgun proteomic analysis. Evidence for activation of the UPR comes from our observation of up-regulated binding immunoglobulin protein (BiP), heat shock proteins, and foldases. We also observed up-regulation of proteins that contribute to the degradation of misfolded or unfolded proteins controlled by the UPS and ERAD pathways. Activation of the UPR may allow neurons to maintain protein homeostasis in the cytosol and ER despite an increase in reactive oxygen species due to oxidative stress, and activation of the UPS and ERAD may further augment clean-up and quality control in the cell. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Expression of Heat Shock Protein Genes in Different Developmental Stages and After Temperature Stress in the Maize Weevil (Coleoptera: Curculionidae).

PubMed

Tungjitwitayakul, Jatuporn; Tatun, Nujira; Vajarasathira, Boongeua; Sakurai, Sho

2015-06-01

The maize weevil, Sitophilus zeamais Motschulsky, is a major pest of rice and other postharvest grain stocks in tropical countries. Heating and cooling treatments have been adopted to control this pest. Because heat shock protein (hsp) genes respond to temperature stress, we examined the association of hsp genes with development and thermal stress in S. zeamais. The temperature response of the insect to heat and cold treatments was assessed at four developmental stages: egg, larva, pupa, and adult. LT50 values at high temperatures were similar among the four developmental stages, while adults were the most tolerant to low temperatures, and eggs, larvae, and pupae exhibited similar LT50 values. Expression levels of three hsps--Szhsp70, Szhsc70, and Szhsp90--fluctuated substantially throughout the four stages at a rearing temperature of 28°C. Heat shock and cold shock increased the expression of all three hsps, and the highest upregulation was observed at 40°C, although the intensity of upregulation varied among the three genes: strongly in Szhsp70, moderately in Szhsp90, and slightly in Szhsc70. Basal expression of the three hsps at 28°C and gene responses to heat and cold shock also varied significantly at the tissue level. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Overexpression of a Phytophthora Cytoplasmic CRN Effector Confers Resistance to Disease, Salinity and Drought in Nicotiana benthamiana.

PubMed

Rajput, Nasir Ahmed; Zhang, Meixiang; Shen, Danyu; Liu, Tingli; Zhang, Qimeng; Ru, Yanyan; Sun, Peng; Dou, Daolong

2015-12-01

The Crinkler (CRN) effector family is produced by oomycete pathogens and may manipulate host physiological and biochemical events inside host cells. Here, PsCRN161 was identified from Phytophthora sojae based on its broad and strong cell death suppression activities. The effector protein contains two predicted nuclear localization signals and localized to nuclei of plant cells, indicating that it may target plant nuclei to modify host cell physiology and function. The chimeric gene GFP:PsCRN161 driven by the Cauliflower mosaic virus (CaMV) 35S promoter was introduced into Nicotiana benthamiana. The four independent PsCRN161-transgenic lines exhibited increased resistance to two oomycete pathogens (P. parasitica and P. capsici) and showed enhanced tolerance to salinity and drought stresses. Digital gene expression profiling analysis showed that defense-related genes, including ABC transporters, Cyt P450 and receptor-like kinases (RLKs), were significantly up-regulated in PsCRN161-transgenic plants compared with GFP (green fluorescent protein) lines, implying that PsCRN161 expression may protect plants from biotic and abiotic stresses by up-regulation of many defense-related genes. The results reveal previously unknown functions of the oomycete effectors, suggesting that the pathogen effectors could be directly used as functional genes for plant molecular breeding for enhancement of tolerance to biotic and abiotic stresses. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

[Free radical modification of proteins in brain structure of Sprague-Dawley rats and some behaviour indicators after prenatal stress].

PubMed

V'iushina, A V; Pritvorova, A V; Flerov, M A

2012-08-01

We studied the influence of late prenatal stress on free radical oxidation processes in Sprague-Dawley rats cortex, striatum, hippocampus, hypothalamus proteins. It was shown that after prenatal stress most changes were observed in hypothalamus and hippocampus. It was shown that in hypothalamus spontaneous oxidation level increased, but level of induced oxidation decreased, the opposite changes were found in hippocampus. Simultaneously minor changes of protein modification were observed in cortex and striatum. It was shown that prenatal stress changed both correlation of proteins free radical oxidation in studied structures and values of these data regarding to control. In test of "open field" motor activity in rats after prenatal stress decreased and time of freezing and grooming increased; opposite, in T-labyrinth motor activity and time of grooming in rats after prenatal stress increased, but time of freezing decreased.

Endoplasmic Reticulum Stress and Lipid Metabolism: Mechanisms and Therapeutic Potential

PubMed Central

Basseri, Sana; Austin, Richard C.

2012-01-01

The endoplasmic reticulum (ER) plays a crucial role in protein folding, assembly, and secretion. Disruption of ER homeostasis may lead to accumulation of misfolded or unfolded proteins in the ER lumen, a condition referred to as ER stress. In response to ER stress, a signal transduction pathway known as the unfolded protein response (UPR) is activated. UPR activation allows the cell to cope with an increased protein-folding demand on the ER. Recent studies have shown that ER stress/UPR activation plays a critical role in lipid metabolism and homeostasis. ER-stress-dependent dysregulation of lipid metabolism may lead to dyslipidemia, insulin resistance, cardiovascular disease, type 2 diabetes, and obesity. In this paper, we examine recent findings illustrating the important role ER stress/UPR signalling pathways play in regulation of lipid metabolism, and how they may lead to dysregulation of lipid homeostasis. PMID:22195283

CML8, an Arabidopsis Calmodulin-Like Protein, Plays a Role in Pseudomonas syringae Plant Immunity.

PubMed

Zhu, Xiaoyang; Robe, Eugénie; Jomat, Lucile; Aldon, Didier; Mazars, Christian; Galaud, Jean-Philippe

2017-02-01

Calcium is a universal second messenger involved in various cellular processes including plant development and stress responses. Its conversion into biological responses requires the presence of calcium sensor relays such as calmodulin (CaM) and calmodulin-like (CML) proteins. While the role of CaM is well described, the functions CML proteins remain largely uncharacterized. Here, we show that Arabidopsis CML8 expression is strongly and transiently induced by Pseudomonas syringae, and reverse genetic approaches indicated that the overexpression of CML8 confers on plants a better resistance to pathogenic bacteria compared with wild-type, knock-down and knock-out lines, indicating that CML8 participates as a positive regulator in plant immunity. However, this difference disappeared when inoculations were performed using bacteria unable to inject effectors into a plant host cell or deficient for some effectors known to target the salicylic acid (SA) signaling pathway. SA content and PR1 protein accumulation were altered in CML8 transgenic lines, supporting a role for CML8 in SA-dependent processes. Pathogen-associated molecular pattern (PAMP) treatments with flagellin and elf18 peptides have no effects on CML8 gene expression and do not modify root growth of CML8 knock-down and overexpressing lines compared with wild-type plants. Collectively, our results support a role for CML8 in plant immunity against P. syringae. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Endoplasmic Reticulum Stress in Beta Cells and Development of Diabetes

PubMed Central

Fonseca, Sonya G.; Burcin, Mark; Gromada, Jesper; Urano, Fumihiko

2009-01-01

The endoplasmic reticulum (ER) is a cellular compartment responsible for multiple important cellular functions including the biosynthesis and folding of newly synthesized proteins destined for secretion, such as insulin. A myriad of pathological and physiological factors perturb ER function and cause dysregulation of ER homeostasis, leading to ER stress. ER stress elicits a signaling cascade to mitigate stress, the Unfolded Protein Response (UPR). As long as the UPR can relieve stress, cells can produce the proper amount of proteins and maintain ER homeostasis. If the UPR, however, fails to maintain ER homeostasis, cells will undergo apoptosis. Activation of the UPR is critical to the survival of insulin-producing pancreatic β-cells with high secretory protein production. Any disruption of ER homeostasis in β-cells can lead to cell death and contribute to the pathogenesis of diabetes. There are several models of ER stress-mediated diabetes. In this review, we outline the underlying molecular mechanisms of ER stress-mediated β-cell dysfunction and death during the progression of diabetes. PMID:19665428

Selective aggregation of the splicing factor Hsh155 suppresses splicing upon genotoxic stress.

PubMed

Mathew, Veena; Tam, Annie S; Milbury, Karissa L; Hofmann, Analise K; Hughes, Christopher S; Morin, Gregg B; Loewen, Christopher J R; Stirling, Peter C

2017-12-04

Upon genotoxic stress, dynamic relocalization events control DNA repair as well as alterations of the transcriptome and proteome, enabling stress recovery. How these events may influence one another is only partly known. Beginning with a cytological screen of genome stability proteins, we find that the splicing factor Hsh155 disassembles from its partners and localizes to both intranuclear and cytoplasmic protein quality control (PQC) aggregates under alkylation stress. Aggregate sequestration of Hsh155 occurs at nuclear and then cytoplasmic sites in a manner that is regulated by molecular chaperones and requires TORC1 activity signaling through the Sfp1 transcription factor. This dynamic behavior is associated with intron retention in ribosomal protein gene transcripts, a decrease in splicing efficiency, and more rapid recovery from stress. Collectively, our analyses suggest a model in which some proteins evicted from chromatin and undergoing transcriptional remodeling during stress are targeted to PQC sites to influence gene expression changes and facilitate stress recovery. © 2017 Mathew et al.

Regulation of Cadmium-Induced Proteomic and Metabolic Changes by 5-Aminolevulinic Acid in Leaves of Brassica napus L.

PubMed Central

Ali, Basharat; Gill, Rafaqat A.; Yang, Su; Gill, Muhammad B.; Farooq, Muhammad A.; Liu, Dan; Daud, Muhammad K.; Ali, Shafaqat; Zhou, Weijun

2015-01-01

It is evident from previous reports that 5-aminolevulinic acid (ALA), like other known plant growth regulators, is effective in countering the injurious effects of heavy metal-stress in oilseed rape (Brassica napus L.). The present study was carried out to explore the capability of ALA to improve cadmium (Cd2+) tolerance in B. napus through physiological, molecular, and proteomic analytical approaches. Results showed that application of ALA helped the plants to adjust Cd2+-induced metabolic and photosynthetic fluorescence changes in the leaves of B. napus under Cd2+ stress. The data revealed that ALA treatment enhanced the gene expressions of antioxidant enzyme activities substantially and could increase the expression to a certain degree under Cd2+ stress conditions. In the present study, 34 protein spots were identified that differentially regulated due to Cd2+ and/or ALA treatments. Among them, 18 proteins were significantly regulated by ALA, including the proteins associated with stress related, carbohydrate metabolism, catalysis, dehydration of damaged protein, CO2 assimilation/photosynthesis and protein synthesis/regulation. From these 18 ALA-regulated proteins, 12 proteins were significantly down-regulated and 6 proteins were up-regulated. Interestingly, it was observed that ALA-induced the up-regulation of dihydrolipoyl dehydrogenase, light harvesting complex photo-system II subunit 6 and 30S ribosomal proteins in the presence of Cd2+ stress. In addition, it was also observed that ALA-induced the down-regulation in thioredoxin-like protein, 2, 3-bisphosphoglycerate, proteasome and thiamine thiazole synthase proteins under Cd2+ stress. Taken together, the present study sheds light on molecular mechanisms involved in ALA-induced Cd2+ tolerance in B. napus leaves and suggests a more active involvement of ALA in plant physiological processes than previously proposed. PMID:25909456

Immunohistochemical evidence for an increased oxidative stress and carbonyl modification of proteins in diabetic glomerular lesions.

PubMed

Suzuki, D; Miyata, T; Saotome, N; Horie, K; Inagi, R; Yasuda, Y; Uchida, K; Izuhara, Y; Yagame, M; Sakai, H; Kurokawa, K

1999-04-01

Advanced glycation end products (AGE) include a variety of protein adducts whose accumulation has been implicated in tissue damage associated with diabetic nephropathy (DN). It was recently demonstrated that among AGE, glycoxidation products, whose formation is closely linked to oxidation, such as carboxymethyllysine (CML) and pentosidine, accumulate in expanded mesangial matrix and nodular lesions in DN, in colocalization with malondialdehyde-lysine (MDA-lysine), a lipoxidation product, whereas pyrraline, another AGE structure whose deposition is rather independent from oxidative stress, was not found within diabetic glomeruli. Because CML, pentosidine, and MDA-lysine are all formed under oxidative stress by carbonyl amine chemistry between protein amino group and carbonyl compounds, their colocalization suggests a local oxidative stress and increased protein carbonyl modification in diabetic glomerular lesions. To address this hypothesis, human renal tissues from patients with DN or IgA nephropathy were examined with specific antibodies to characterize most, if not all, carbonyl modifications of proteins by autoxidation products of carbohydrates, lipids, and amino acids: CML (derived from carbohydrates, lipids, and amino acid), pentosidine (derived from carbohydrates), MDA-lysine (derived from lipids), 4-hydroxynonenal-protein adduct (derived from lipids), and acrolein-protein adduct (derived from lipids and amino acid). All of the protein adducts were identified in expanded mesangial matrix and nodular lesions in DN. In IgA nephropathy, another primary glomerular disease leading to end-stage renal failure, despite positive staining for MDA-lysine and 4-hydroxynonenal-protein adduct in the expanded mesangial area, CML, pentosidine, and acrolein-protein adduct immunoreactivities were only faint in glomeruli. These data suggest a broad derangement in nonenzymatic biochemistry in diabetic glomerular lesions, and implicate an increased local oxidative stress and carbonyl modification of proteins in diabetic glomerular tissue damage ("carbonyl stress").

Comparative Proteomic Analysis of the Stolon Cold Stress Response between the C4 Perennial Grass Species Zoysia japonica and Zoysia metrella

PubMed Central

Xuan, Jiping; Song, Yufeng; Zhang, Hongxiao; Liu, Jianxiu; Guo, Zhongren; Hua, Yuelou

2013-01-01

Zoysiagrass, the most cold-tolerant grass among the warm-season turfgrasses, is often used as a model species for isolating cellular components related to cold stress. To understand the proteomic responses to cold stress in zoysiagrass stolons, we extracted stolon proteins from Zoysia japonica , cv. Meyer (cold-tolerant) and Z . metrella , cv. Diamond (cold-sensitive), which were grown with or without cold treatment. Approximately 700 proteins were resolved on 2-DE gels, and 70 protein spots were differentially accumulated. We further observed that 45 of the identified proteins participate in 10 metabolic pathways and cellular processes. A significantly greater number of proteins accumulated in the Meyer than in the Diamond and 15 increased proteins were detected only in the Meyer cultivar under cold stress. Furthermore, we propose a cold stress-responsive protein network composed of several different functional components that exhibits a balance between reactive oxygen species (ROS) production and scavenging, accelerated protein biosynthesis and proteolysis, reduced protein folding, enhanced photosynthesis, abundant energy supply and enhanced biosynthesis of carbohydrates and nucleotides. Generally, the cold-tolerant Meyer cultivar showed a greater ROS scavenging ability, more abundant energy supply and increased photosynthesis and protein synthesis than did the cold-sensitive Diamond cultivar, which may partly explain why Meyer is more cold tolerant. PMID:24086619

LINE-1 ORF1 protein localizes in stress granules with other RNA-binding proteins, including components of RNA interference RNA-induced silencing complex.

PubMed

Goodier, John L; Zhang, Lili; Vetter, Melissa R; Kazazian, Haig H

2007-09-01

LINE-1 retrotransposons constitute one-fifth of human DNA and have helped shape our genome. A full-length L1 encodes a 40-kDa RNA-binding protein (ORF1p) and a 150-kDa protein (ORF2p) with endonuclease and reverse transcriptase activities. ORF1p is distinctive in forming large cytoplasmic foci, which we identified as cytoplasmic stress granules. A phylogenetically conserved central region of the protein is critical for wild-type localization and retrotransposition. Yeast two-hybrid screens revealed several RNA-binding proteins that coimmunoprecipitate with ORF1p and colocalize with ORF1p in foci. Two of these proteins, YB-1 and hnRNPA1, were previously reported in stress granules. We identified additional proteins associated with stress granules, including DNA-binding protein A, 9G8, and plasminogen activator inhibitor RNA-binding protein 1 (PAI-RBP1). PAI-RBP1 is a homolog of VIG, a part of the Drosophila melanogaster RNA-induced silencing complex (RISC). Other RISC components, including Ago2 and FMRP, also colocalize with PAI-RBP1 and ORF1p. We suggest that targeting ORF1p, and possibly the L1 RNP, to stress granules is a mechanism for controlling retrotransposition and its associated genetic and cellular damage.

Dehydration-responsive nuclear proteome landscape of chickpea (Cicer arietinum L.) reveals phosphorylation-mediated regulation of stress response.

PubMed

Barua, Pragya; Lande, Nilesh Vikram; Subba, Pratigya; Gayen, Dipak; Pinto, Sneha; Prasad, T S Keshav; Chakraborty, Subhra; Chakraborty, Niranjan

2018-05-10

Non-availability of water or dehydration remains recurring climatic disorder affecting yield of major food crops, legumes in particular. Nuclear proteins (NP) and phosphoproteins (NPPs) execute crucial cellular functions that form the regulatory hub for coordinated stress response. Phosphoproteins hold enormous influence over cellular signalling. Four-week-old seedlings of a grain legume, chickpea, were subjected to gradual dehydration and nuclear proteins were extracted from unstressed control as well as from 72 and 144 h stressed tissues. We identified 4832 NPs and 478 phosphosites, corresponding to 299 unique NPPs involved in multivariate cellular processes including protein modification and gene expression regulation, among others. The identified proteins included several novel kinases, phosphatases and transcription factors, besides 660 uncharacterised proteins. Spliceosome complex and splicing related proteins were dominant among differentially regulated NPPs, indicating their dehydration modulated regulation. Phospho-motif analysis revealed stress-induced enrichment of proline-directed serine phosphorylation. Association mapping of NPPs revealed predominance of differential phosphorylation of spliceosome and splicing associated proteins. Also, regulatory proteins of key processes viz., protein degradation, regulation of flowering time and circadian clock were observed to undergo dehydration-induced dephosphorylation. The characterization of novel regulatory proteins would provide new insights into stress adaptation and enable directed genetic manipulations for developing climate-resilient crops. This article is protected by copyright. All rights reserved.

Relationship between antioxidant capacity, oxidative stress, and feed efficiency in beef steers.

PubMed

Russell, J R; Sexten, W J; Kerley, M S; Hansen, S L

2016-07-01

Feed efficiency (FE) can vary between individuals but sources of variation are not well characterized. Oxidative stress is among the biological mechanisms believed to contribute to variation. The objective of this study was to evaluate the relationship between FE, antioxidant activity, and oxidative stress in feedlot steers representing phenotypic extremes for FE. Crossbred beef steers ( = 181) fed 70-d growing phase (GP) whole-shell corn-based (G-Corn) or rye baleage and soybean hull-based (G-Rough) diets in GrowSafe bunks at the University of Missouri were shipped to Iowa State University where the 12 most feed efficient (HFE) and 12 least feed efficient (LFE) steers from each diet (n = 48; 467 kg [SD 51]) were selected for evaluation. Steers received diets similar to GP diets, and 3 d after arrival, blood was sampled to evaluate antioxidant activity and oxidative stress markers for the GP following transit. Steers were transitioned to finishing phase (FP) cracked corn-based (F-Corn) or dried distillers' grains and soybean hull-based (F-Byp) diets, and on FP d 97, blood samples for the FP were collected. Data for the GP were analyzed as a 2 × 2 factorial, and data for the FP were analyzed as a 2 × 2 × 2 factorial using PROC MIXED of SAS. No GP diet × FP diet, FP diet × FE group, or 3-way interactions were noted ( ≥ 0.11) for FP measures. Steers fed the G-Rough diet had greater ( = 0.04) GP plasma protein carbonyl concentrations. During the GP, HFE steers had greater ( ≤ 0.04) protein carbonyl and ratio of oxidized:reduced blood lysate glutathione concentrations than LFE steers. There were GP diet × FE group interactions ( ≤ 0.03) during the GP and FP. During the GP, total blood lysate superoxide dismutase (SOD) activity was greater ( ≤ 0.03) in G-Rough/LFE steers than in G-Rough/HFE and G-Corn/LFE steers; G-Corn/HFE steers were intermediate. The G-Rough/LFE steers had greater ( < 0.04) glutathione peroxidase (GPX) activity than other groups and greater ( = 0.03) plasma malondialdehyde concentrations than G-Corn/LFE steers. During the FP, the G-Rough/LFE steers had greater ( ≤ 0.04) GPX activity than G-Rough/HFE and G-Corn/LFE steers; G-Corn/HFE steers were intermediate. The F-Byp diet had greater ( < 0.01) protein carbonyl than the F-Corn diet, and no other FP diet effects were noted ( ≥ 0.3) for any FP measures. The GP diet and FE groups had stronger relationships with antioxidant activity and oxidative stress markers measured for the GP than for the FP. Overall, antioxidant activity may play a role in FE as LFE steers, driven largely by G-Rough/LFE steers, had greater SOD activity and GPX activity than HFE steers, potentially using a greater proportion of energy otherwise available for tissue accretion.

Astrocytes and endoplasmic reticulum stress: A bridge between obesity and neurodegenerative diseases.

PubMed

Martin-Jiménez, Cynthia A; García-Vega, Ángela; Cabezas, Ricardo; Aliev, Gjumrakch; Echeverria, Valentina; González, Janneth; Barreto, George E

2017-11-01

Endoplasmic reticulum (ER) is a subcellular organelle involved in protein folding and processing. ER stress constitutes a cellular process characterized by accumulation of misfolded proteins, impaired lipid metabolism and induction of inflammatory responses. ER stress has been suggested to be involved in several human pathologies, including neurodegenerative diseases and obesity. Different studies have shown that both neurodegenerative diseases and obesity trigger similar cellular responses to ER stress. Moreover, both diseases are assessed in astrocytes as evidences suggest these cells as key regulators of brain homeostasis. However, the exact contributions to the effects of ER stress in astrocytes in the various neurodegenerative diseases and its relation with obesity are not well known. Here, we discuss recent advances in the understanding of molecular mechanisms that regulate ER stress-related disorders in astrocytes such as obesity and neurodegeneration. Moreover, we outline the correlation between the activated proteins of the unfolded protein response (UPR) in these pathological conditions in order to identify possible therapeutic targets for ER stress in astrocytes. We show that ER stress in astrocytes shares UPR activation pathways during both obesity and neurodegenerative diseases, demonstrating that UPR related proteins like ER chaperone GRP 78/Bip, PERK pathway and other exogenous molecules ameliorate UPR response and promote neuroprotection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hexavalent chromium, a lung carcinogen, confers resistance to thermal stress and interferes with heat shock protein expression in human bronchial epithelial cells.

PubMed

Abreu, Patrícia L; Cunha-Oliveira, Teresa; Ferreira, Leonardo M R; Urbano, Ana M

2018-03-16

Exposure to hexavalent chromium [Cr(VI)], a lung carcinogen, triggers several types of cellular stresses, namely oxidative, genotoxic and proteotoxic stresses. Given the evolutionary character of carcinogenesis, it is tempting to speculate that cells that survive the stresses produced by this carcinogen become more resistant to subsequent stresses, namely those encountered during neoplastic transformation. To test this hypothesis, we determined whether pre-incubation with Cr(VI) increased the resistance of human bronchial epithelial cells (BEAS-2B cells) to the antiproliferative action of acute thermal shock, used here as a model for stress. In line with the proposed hypothesis, it was observed that, at mildly cytotoxic concentrations, Cr(VI) attenuated the antiproliferative effects of both cold and heat shock. Mechanistically, Cr(VI) interfered with the expression of two components of the stress response pathway: heat shock proteins Hsp72 and Hsp90α. Specifically, Cr(VI) significantly depleted the mRNA levels of the former and the protein levels of the latter. Significantly, these two proteins are members of heat shock protein (Hsp) families (Hsp70 and Hsp90, respectively) that have been implicated in carcinogenesis. Thus, our results confirm and extend previous studies showing the capacity of Cr(VI) to interfere with the expression of stress response components.

ABA signaling in stress-response and seed development.

PubMed

Nakashima, Kazuo; Yamaguchi-Shinozaki, Kazuko

2013-07-01

KEY MESSAGE : We review the recent progress on ABA signaling, especially ABA signaling for ABA-dependent gene expression, including the AREB/ABF regulon, SnRK2 protein kinase, 2C-type protein phosphatases and ABA receptors. Drought negatively impacts plant growth and the productivity of crops. Drought causes osmotic stress to organisms, and the osmotic stress causes dehydration in plant cells. Abscisic acid (ABA) is produced under osmotic stress conditions, and it plays an important role in the stress response and tolerance of plants. ABA regulates many genes under osmotic stress conditions. It also regulates gene expression during seed development and germination. The ABA-responsive element (ABRE) is the major cis-element for ABA-responsive gene expression. ABRE-binding protein (AREB)/ABRE-binding factor (ABF) transcription factors (TFs) regulate ABRE-dependent gene expression. Other TFs are also involved in ABA-responsive gene expression. SNF1-related protein kinases 2 are the key regulators of ABA signaling including the AREB/ABF regulon. Recently, ABA receptors and group A 2C-type protein phosphatases were shown to govern the ABA signaling pathway. Moreover, recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress-response and seed development. The control of the expression of ABA signaling factors may improve tolerance to environmental stresses.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quaresma, Alexandre J.C.; Bressan, G.C.; Institute of Biology, University of Campinas - UNICAMP, 13083-970, Campinas, SP

Eukaryotic gene expression is regulated on different levels ranging from pre-mRNA processing to translation. One of the most characterized families of RNA-binding proteins is the group of hnRNPs: heterogenous nuclear ribonucleoproteins. Members of this protein family play important roles in gene expression control and mRNAs metabolism. In the cytoplasm, several hnRNPs proteins are involved in RNA-related processes and they can be frequently found in two specialized structures, known as GW-bodies (GWbs), previously known as processing bodies: PBs, and stress granules, which may be formed in response to specific stimuli. GWbs have been early reported to be involved in the mRNAmore » decay process, acting as a site of mRNA degradation. In a similar way, stress granules (SGs) have been described as cytoplasmic aggregates, which contain accumulated mRNAs in cells under stress conditions and present reduced or inhibited translation. Here, we characterized the hnRNP Q localization after different stress conditions. hnRNP Q is a predominantly nuclear protein that exhibits a modular organization and several RNA-related functions. Our data suggest that the nuclear localization of hnRNP Q might be modified after different treatments, such as: PMA, thapsigargin, arsenite and heat shock. Under different stress conditions, hnRNP Q can fully co-localize with the endoplasmatic reticulum specific chaperone, BiP. However, under stress, this protein only co-localizes partially with the proteins: GW182 - GWbs marker protein and TIA-1 stress granule component.« less

Perceived Stress in University Students Studying in a Further Education College

ERIC Educational Resources Information Center

Shaw, Matthew Peter; Peart, Daniel James; Fairhead, Orrin James William

2017-01-01

Previous research investigating perceived stress and mental health in UK university students has used a sample population from higher education institutes (HEIs). To the authors' knowledge, there is no literature specifically examining stress in a student population within a higher education in further education (HE-in-FE) environment. The aim of…

Acculturative Stress and Coping: Gender Differences among Korean and Korean American University Students

ERIC Educational Resources Information Center

Lee, Diane Sookyoung; Padilla, Amado M.

2014-01-01

In this study we examined acculturative stress and coping among 86 students of Korean heritage at an American university. Participants indicated their stress levels on 3 scales of cultural adaptation: discrimination, language and cultural ties, and social distance. Findings show that self-identified Korean students displayed higher levels of…

Exercise and Glycemic Control: Focus on Redox Homeostasis and Redox-Sensitive Protein Signaling

PubMed Central

Parker, Lewan; Shaw, Christopher S.; Stepto, Nigel K.; Levinger, Itamar

2017-01-01

Physical inactivity, excess energy consumption, and obesity are associated with elevated systemic oxidative stress and the sustained activation of redox-sensitive stress-activated protein kinase (SAPK) and mitogen-activated protein kinase signaling pathways. Sustained SAPK activation leads to aberrant insulin signaling, impaired glycemic control, and the development and progression of cardiometabolic disease. Paradoxically, acute exercise transiently increases oxidative stress and SAPK signaling, yet postexercise glycemic control and skeletal muscle function are enhanced. Furthermore, regular exercise leads to the upregulation of antioxidant defense, which likely assists in the mitigation of chronic oxidative stress-associated disease. In this review, we explore the complex spatiotemporal interplay between exercise, oxidative stress, and glycemic control, and highlight exercise-induced reactive oxygen species and redox-sensitive protein signaling as important regulators of glucose homeostasis. PMID:28529499

Increasing abscisic acid levels by immunomodulation in barley grains induces precocious maturation without changing grain composition.

PubMed

Staroske, Nicole; Conrad, Udo; Kumlehn, Jochen; Hensel, Götz; Radchuk, Ruslana; Erban, Alexander; Kopka, Joachim; Weschke, Winfriede; Weber, Hans

2016-04-01

Abscisic acid (ABA) accumulates in seeds during the transition to the seed filling phase. ABA triggers seed maturation, storage activity, and stress signalling and tolerance. Immunomodulation was used to alter the ABA status in barley grains, with the resulting transgenic caryopses responding to the anti-ABA antibody gene expression with increased accumulation of ABA. Calculation of free versus antibody-bound ABA reveals large excess of free ABA, increasing signficantly in caryopses from 10 days after fertilization. Metabolite and transcript profiling in anti-ABA grains expose triggered and enhanced ABA-functions such as transcriptional up-regulation of sucrose-to-starch metabolism, storage protein synthesis and ABA-related signal transduction. Thus, enhanced ABA during transition phases induces precocious maturation but negatively interferes with growth and development. Anti-ABA grains display broad constitutive gene induction related to biotic and abiotic stresses. Most of these genes are ABA- and/or stress-inducible, including alcohol and aldehyde dehydrogenases, peroxidases, chaperones, glutathione-S-transferase, drought- and salt-inducible proteins. Conclusively, ABA immunomodulation results in precocious ABA accumulation that generates an integrated response of stress and maturation. Repression of ABA signalling, occurring in anti-ABA grains, potentially antagonizes effects caused by overshooting production. Finally, mature grain weight and composition are unchanged in anti-ABA plants, although germination is somewhat delayed. This indicates that anti-ABA caryopses induce specific mechanisms to desensitize ABA signalling efficiently, which finally yields mature grains with nearly unchanged dry weight and composition. Such compensation implicates the enormous physiological and metabolic flexibilities of barley grains to adjust effects of unnaturally high ABA amounts in order to ensure and maintain proper grain development. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Stress among medical students: A cross-sectional study from a North Indian Medical University.

PubMed

Garg, Kabir; Agarwal, Manu; Dalal, Pronob Kumar

2017-01-01

The aim is to study stress among medical students and the relationship of stress to the year of study and gender. A single-point, cross-sectional, observational study of students of a medical university in North India divided on the basis of the semester of their course. The study was done using the higher education stress inventory. A total of 251 students were included in the study. Worry about future endurance and capacity was rated the highest by the final year students while faculty shortcomings and insufficient feedback were rated highest by the 2 nd -year students and financial concerns the highest by the 1 st -year students. Males rated financial concerns higher than females. The study would provide insight to the university authorities to make remedies based on the expectations and feedback of the students. the current study shows that stress amongst medical students is a dynamic process as the reasons of stress vary depending on the stage of curriculum. The college/university administration can mitigate this by taking appropriate steps as needed.

mTORC1 Coordinates Protein Synthesis and Immunoproteasome Formation via PRAS40 to Prevent Accumulation of Protein Stress.

PubMed

Yun, Young Sung; Kim, Kwan Hyun; Tschida, Barbara; Sachs, Zohar; Noble-Orcutt, Klara E; Moriarity, Branden S; Ai, Teng; Ding, Rui; Williams, Jessica; Chen, Liqiang; Largaespada, David; Kim, Do-Hyung

2016-02-18

Reduction of translational fidelity often occurs in cells with high rates of protein synthesis, generating defective ribosomal products. If not removed, such aberrant proteins can be a major source of cellular stress causing human diseases. Here, we demonstrate that mTORC1 promotes the formation of immunoproteasomes for efficient turnover of defective proteins and cell survival. mTORC1 sequesters precursors of immunoproteasome β subunits via PRAS40. When activated, mTORC1 phosphorylates PRAS40 to enhance protein synthesis and simultaneously to facilitate the assembly of the β subunits for forming immunoproteasomes. Consequently, the PRAS40 phosphorylations play crucial roles in clearing aberrant proteins that accumulate due to mTORC1 activation. Mutations of RAS, PTEN, and TSC1, which cause mTORC1 hyperactivation, enhance immunoproteasome formation in cells and tissues. Those mutations increase cellular dependence on immunoproteasomes for stress response and survival. These results define a mechanism by which mTORC1 couples elevated protein synthesis with immunoproteasome biogenesis to protect cells against protein stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Role of α-crystallin B in regulation of stress induced cardiomyocyte apoptosis.

PubMed

Ganguly, Subhalakshmi; Mitra, Arkadeep; Sarkar, Sagartirtha

2014-01-01

Cardiovascular disease is the leading cause of death worldwide. Recently emerging evidence suggests that cardiomyocyte apoptosis is one of the major pathogenic factors in heart diseases leading to heart failure. Cardiomyocytes undergo apoptosis in response to a wide variety of cellular stresses including protein folding stress at Endoplasmic reticulum (ER). Stressed myocytes elicit an adaptive response referred as Unfolded Protein Response (UPR) by inducing accumulation of heat shock proteins (HSPs) to mitigate the ER stress. HSPs act as molecular chaperons by assisting correct folding of the aggregated misfolded proteins in ER lumen. α-Crystallin B (CRYAB) is an abundant small HSP that confers protection to cardiomyocytes against various stress stimuli. Recent evidence indicates that CRYAB directly interacts with several components of ER stress and also mitochondrial apoptotic pathway. Based on currently available literature this mini review will focus on how CRYAB confers protection to stressed myocardium thereby emphasizing its function as antiapoptotic molecule. Understanding the interplay between CRYAB and the key components in the apoptotic signaling cascade mediated by ER and mitochondria will help in development of novel therapies for cardiac diseases.

Poliovirus infection induces the co-localization of cellular protein SRp20 with TIA-1, a cytoplasmic stress granule protein.

PubMed

Fitzgerald, Kerry D; Semler, Bert L

2013-09-01

Different types of environmental stress cause mammalian cells to form cytoplasmic foci, termed stress granules, which contain mRNPs that are translationally silenced. These foci are transient and dynamic, and contain components of the cellular translation machinery as well as certain mRNAs and RNA binding proteins. Stress granules are known to be induced by conditions such as hypoxia, nutrient deprivation, and oxidative stress, and a number of cellular factors have been identified that are commonly associated with these foci. More recently it was discovered that poliovirus infection also induces the formation of stress granules, although these cytoplasmic foci appear to be somewhat compositionally unique. Work described here examined the punctate pattern of SRp20 (a host cell mRNA splicing protein) localization in the cytoplasm of poliovirus-infected cells, demonstrating the partial co-localization of SRp20 with the stress granule marker protein TIA-1. We determined that SRp20 does not co-localize with TIA-1, however, under conditions of oxidative stress, indicating that the close association of these two proteins during poliovirus infection is not representative of a general response to cellular stress. We confirmed that the expression of a dominant negative version of TIA-1 (TIA-1-PRD) results in the dissociation of stress granules. Finally, we demonstrated that expression of wild type TIA-1 or dominant negative TIA-1-PRD in cells during poliovirus infection does not dramatically affect viral translation. Taken together, these studies provide a new example of the unique cytoplasmic foci that form during poliovirus infection. Copyright © 2013 Elsevier B.V. All rights reserved.

Changes in the Phosphoproteome and Metabolome Link Early Signaling Events to Rearrangement of Photosynthesis and Central Metabolism in Salinity and Oxidative Stress Response in Arabidopsis1

PubMed Central

Chen, Yanmei; Hoehenwarter, Wolfgang

2015-01-01

Salinity and oxidative stress are major factors affecting and limiting the productivity of agricultural crops. The molecular and biochemical processes governing the plant response to abiotic stress have often been researched in a reductionist manner. Here, we report a systemic approach combining metabolic labeling and phosphoproteomics to capture early signaling events with quantitative metabolome analysis and enzyme activity assays to determine the effects of salt and oxidative stress on plant physiology. K+ and Na+ transporters showed coordinated changes in their phosphorylation pattern, indicating the importance of dynamic ion homeostasis for adaptation to salt stress. Unique phosphorylation sites were found for Arabidopsis (Arabidopsis thaliana) SNF1 kinase homolog10 and 11, indicating their central roles in the stress-regulated responses. Seven Sucrose Non-fermenting1-Related Protein Kinase2 kinases showed varying levels of phosphorylation at multiple serine/threonine residues in their kinase domain upon stress, showing temporally distinct modulation of the various isoforms. Salinity and oxidative stress also lead to changes in protein phosphorylation of proteins central to photosynthesis, in particular the kinase State Transition Protein7 required for state transition and light-harvesting II complex proteins. Furthermore, stress-induced changes of the phosphorylation of enzymes of central metabolism were observed. The phosphorylation patterns of these proteins were concurrent with changes in enzyme activity. This was reflected by altered levels of metabolites, such as the sugars sucrose and fructose, glycolysis intermediates, and amino acids. Together, our study provides evidence for a link between early signaling in the salt and oxidative stress response that regulates the state transition of photosynthesis and the rearrangement of primary metabolism. PMID:26471895

The Stress Granule RNA-Binding Protein TIAR-1 Protects Female Germ Cells from Heat Shock in Caenorhabditis elegans.

PubMed

Huelgas-Morales, Gabriela; Silva-García, Carlos Giovanni; Salinas, Laura S; Greenstein, David; Navarro, Rosa E

2016-04-07

In response to stressful conditions, eukaryotic cells launch an arsenal of regulatory programs to protect the proteome. One major protective response involves the arrest of protein translation and the formation of stress granules, cytoplasmic ribonucleoprotein complexes containing the conserved RNA-binding proteins TIA-1 and TIAR. The stress granule response is thought to preserve mRNA for translation when conditions improve. For cells of the germline-the immortal cell lineage required for sexual reproduction-protection from stress is critically important for perpetuation of the species, yet how stress granule regulatory mechanisms are deployed in animal reproduction is incompletely understood. Here, we show that the stress granule protein TIAR-1 protects the Caenorhabditis elegans germline from the adverse effects of heat shock. Animals containing strong loss-of-function mutations in tiar-1 exhibit significantly reduced fertility compared to the wild type following heat shock. Analysis of a heat-shock protein promoter indicates that tiar-1 mutants display an impaired heat-shock response. We observed that TIAR-1 was associated with granules in the gonad core and oocytes during several stressful conditions. Both gonad core and oocyte granules are dynamic structures that depend on translation; protein synthesis inhibitors altered their formation. Nonetheless, tiar-1 was required for the formation of gonad core granules only. Interestingly, the gonad core granules did not seem to be needed for the germ cells to develop viable embryos after heat shock. This suggests that TIAR-1 is able to protect the germline from heat stress independently of these structures. Copyright © 2016 Huelgas-Morales et al.

The Stress Granule RNA-Binding Protein TIAR-1 Protects Female Germ Cells from Heat Shock in Caenorhabditis elegans

PubMed Central

Huelgas-Morales, Gabriela; Silva-García, Carlos Giovanni; Salinas, Laura S.; Greenstein, David; Navarro, Rosa E.

2016-01-01

In response to stressful conditions, eukaryotic cells launch an arsenal of regulatory programs to protect the proteome. One major protective response involves the arrest of protein translation and the formation of stress granules, cytoplasmic ribonucleoprotein complexes containing the conserved RNA-binding proteins TIA-1 and TIAR. The stress granule response is thought to preserve mRNA for translation when conditions improve. For cells of the germline—the immortal cell lineage required for sexual reproduction—protection from stress is critically important for perpetuation of the species, yet how stress granule regulatory mechanisms are deployed in animal reproduction is incompletely understood. Here, we show that the stress granule protein TIAR-1 protects the Caenorhabditis elegans germline from the adverse effects of heat shock. Animals containing strong loss-of-function mutations in tiar-1 exhibit significantly reduced fertility compared to the wild type following heat shock. Analysis of a heat-shock protein promoter indicates that tiar-1 mutants display an impaired heat-shock response. We observed that TIAR-1 was associated with granules in the gonad core and oocytes during several stressful conditions. Both gonad core and oocyte granules are dynamic structures that depend on translation; protein synthesis inhibitors altered their formation. Nonetheless, tiar-1 was required for the formation of gonad core granules only. Interestingly, the gonad core granules did not seem to be needed for the germ cells to develop viable embryos after heat shock. This suggests that TIAR-1 is able to protect the germline from heat stress independently of these structures. PMID:26865701

Stress and cardiometabolic manifestations among Saudi students entering universities: a cross-sectional observational study.

PubMed

Al-Daghri, Nasser M; Al-Othman, Abdulaziz; Al-Attas, Omar S; Alkharfy, Khalid M; Alokail, Majed S; Albanyan, Abdulmajeed; Sabico, Shaun; Chrousos, George P

2014-04-23

In this observational study, we aimed to see whether transition in Saudi students entering university life could be a breeding stage for cardiometabolic risk factor emergence and clustering. A total of 1878 apparently healthy Saudi students of the Preparatory Year, King Saud University, Riyadh, KSA (1112 men and 766 women) spanning 2 academic years were included. They were divided into 2 groups based on the validated perceived stress test (PST). Anthropometrics were obtained and fasting blood samples were collected for measurement of fasting blood glucose and a lipid profile. PST score (>27) considered indicative of stress was noted in 44.4% of students. The prevalence of this score was higher in women than in men (49.7% versus 40.7%). The prevalence of obesity, hypertension and dyslipidemia was significantly higher in men than women (p < 0.01), and this was even more apparent among stressed men, who had a significantly higher prevalence of all the above cardiometabolic factors than the non-stressed ones (p < 0.01). Perceived stress is alarmingly high among Saudi students entering universities. This study sheds light on the social responsibility of universities in promoting a healthy lifestyle, particularly in this age group, when exposure to different kinds of stressors may result in body weight and metabolic changes.

TaHsfA6f is a transcriptional activator that regulates a suite of heat stress protection genes in wheat (Triticum aestivum L.) including previously unknown Hsf targets.

PubMed

Xue, Gang-Ping; Drenth, Janneke; McIntyre, C Lynne

2015-02-01

Heat stress is a significant environmental factor adversely affecting crop yield. Crop adaptation to high-temperature environments requires transcriptional reprogramming of a suite of genes involved in heat stress protection. This study investigated the role of TaHsfA6f, a member of the A6 subclass of heat shock transcription factors, in the regulation of heat stress protection genes in Triticum aestivum (bread wheat), a poorly understood phenomenon in this crop species. Expression analysis showed that TaHsfA6f was expressed constitutively in green organs but was markedly up-regulated during heat stress. Overexpression of TaHsfA6f in transgenic wheat using a drought-inducible promoter resulted in up-regulation of heat shock proteins (HSPs) and a number of other heat stress protection genes that included some previously unknown Hsf target genes such as Golgi anti-apoptotic protein (GAAP) and the large isoform of Rubisco activase. Transgenic wheat plants overexpressing TaHsfA6f showed improved thermotolerance. Transactivation assays showed that TaHsfA6f activated the expression of reporter genes driven by the promoters of several HSP genes (TaHSP16.8, TaHSP17, TaHSP17.3, and TaHSP90.1-A1) as well as TaGAAP and TaRof1 (a co-chaperone) under non-stress conditions. DNA binding analysis revealed the presence of high-affinity TaHsfA6f-binding heat shock element-like motifs in the promoters of these six genes. Promoter truncation and mutagenesis analyses identified TaHsfA6f-binding elements that were responsible for transactivation of TaHSP90.1-A1 and TaGAAP by TaHsfA6f. These data suggest that TaHsfA6f is a transcriptional activator that directly regulates TaHSP, TaGAAP, and TaRof1 genes in wheat and its gene regulatory network has a positive impact on thermotolerance. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Tianeptine, olanzapine and fluoxetine show similar restoring effects on stress induced molecular changes in mice brain: An FT-IR study

NASA Astrophysics Data System (ADS)

Türker-Kaya, Sevgi; Mutlu, Oğuz; Çelikyurt, İpek K.; Akar, Furuzan; Ulak, Güner

2016-05-01

Chronic stress which can cause a variety of disorders and illness ranging from metabolic and cardiovascular to mental leads to alterations in content, structure and dynamics of biomolecules in brain. The determination of stress-induced changes along with the effects of antidepressant treatment on these parameters might bring about more effective therapeutic strategies. In the present study, we investigated unpredictable chronic mild stress (UCMS)-induced changes in biomolecules in mouse brain and the restoring effects of tianeptine (TIA), olanzapine (OLZ) and fluoxetine (FLX) on these variations, by Fourier transform infrared (FT-IR) spectroscopy. The results revealed that chronic stress causes different membrane packing and an increase in lipid peroxidation, membrane fluidity. A significant increment for lipid/protein, Cdbnd O/lipid, CH3/lipid, CH2/lipid, PO-2/lipid, COO-/lipid and RNA/protein ratios but a significant decrease for lipid/protein ratios were also obtained. Additionally, altered protein secondary structure components were estimated, such as increment in random coils and beta structures. The administration of TIA, OLZ and FLX drugs restored these stress-induced variations except for alterations in protein structure and RNA/protein ratio. This may suggest that these drugs have similar restoring effects on the consequences of stress activity in brain, in spite of the differences in their action mechanisms. All findings might have importance in understanding molecular mechanisms underlying chronic stress and contribute to studies aimed for drug development.

The Heat Shock Response and Acute Lung Injury

PubMed Central

Wheeler, Derek S.; Wong, Hector R.

2006-01-01

All cells respond to stress through the activation of primitive, evolutionarily conserved genetic programs that maintain homeostasis and assure cell survival. Stress adaptation, which is known in the literature by a myriad of terms, including tolerance, desensitization, conditioning, and reprogramming, is a common paradigm found throughout nature, in which a primary exposure of a cell or organism to a stressful stimulus (e.g., heat) results in an adaptive response by which a second exposure to the same stimulus produces a minimal response. More interesting is the phenomenon of cross-tolerance, by which a primary exposure to a stressful stimulus results in an adaptive response whereby the cell or organism is resistant to a subsequent stress that is different from the initial stress (i.e. exposure to heat stress leading to resistance to oxidant stress). The heat shock response is one of the more commonly described examples of stress adaptation and is characterized by the rapid expression of a unique group of proteins collectively known as heat shock proteins (also commonly referred to as stress proteins). The expression of heat shock proteins is well described in both whole lungs and in specific lung cells from a variety of species and in response to a variety of stressors. More importantly, in vitro data, as well as data from various animal models of acute lung injury, demonstrate that heat shock proteins, especially Hsp27, Hsp32, Hsp60, and Hsp70 have an important cytoprotective role during lung inflammation and injury. PMID:17157189

Self-Assembled Superparamagnetic Iron Oxide Nanoclusters for Universal Cell Labeling and MRI

NASA Astrophysics Data System (ADS)

Chen, Shuzhen; Zhang, Jun; Jiang, Shengwei; Lin, Gan; Luo, Bing; Yao, Huan; Lin, Yuchun; He, Chengyong; Liu, Gang; Lin, Zhongning

2016-05-01

Superparamagnetic iron oxide (SPIO) nanoparticles have been widely used in a variety of biomedical applications, especially as contrast agents for magnetic resonance imaging (MRI) and cell labeling. In this study, SPIO nanoparticles were stabilized with amphiphilic low molecular weight polyethylenimine (PEI) in an aqueous phase to form monodispersed nanocomposites with a controlled clustering structure. The iron-based nanoclusters with a size of 115.3 ± 40.23 nm showed excellent performance on cellular uptake and cell labeling in different types of cells, moreover, which could be tracked by MRI with high sensitivity. The SPIO nanoclusters presented negligible cytotoxicity in various types of cells as detected using MTS, LDH, and flow cytometry assays. Significantly, we found that ferritin protein played an essential role in protecting stress from SPIO nanoclusters. Taken together, the self-assembly of SPIO nanoclusters with good magnetic properties provides a safe and efficient method for universal cell labeling with noninvasive MRI monitoring capability.

Chimeric tRNAs as tools to induce proteome damage and identify components of stress responses.

PubMed

Geslain, Renaud; Cubells, Laia; Bori-Sanz, Teresa; Alvarez-Medina, Roberto; Rossell, David; Martí, Elisa; Ribas de Pouplana, Lluís

2010-03-01

Misfolded proteins are caused by genomic mutations, aberrant splicing events, translation errors or environmental factors. The accumulation of misfolded proteins is a phenomenon connected to several human disorders, and is managed by stress responses specific to the cellular compartments being affected. In wild-type cells these mechanisms of stress response can be experimentally induced by expressing recombinant misfolded proteins or by incubating cells with large concentrations of amino acid analogues. Here, we report a novel approach for the induction of stress responses to protein aggregation. Our method is based on engineered transfer RNAs that can be expressed in cells or tissues, where they actively integrate in the translation machinery causing general proteome substitutions. This strategy allows for the introduction of mutations of increasing severity randomly in the proteome, without exposing cells to unnatural compounds. Here, we show that this approach can be used for the differential activation of the stress response in the Endoplasmic Reticulum (ER). As an example of the applications of this method, we have applied it to the identification of human microRNAs activated or repressed during unfolded protein stress.

SOD1 suppresses maternal hyperglycemia-increased iNOS expression and consequent nitrosative stress in diabetic embryopathy

PubMed Central

Weng, Hongbo; Li, Xuezheng; Reece, E. Albert; Yang, Peixin

2012-01-01

Objectives Hyperglycemia induces oxidative stress and increases inducible nitric oxide synthase (iNOS) expression. We hypothesized that oxidative stress is responsible for hyperglycemia-induced iNOS expression. Study Design iNOS-luciferase activities, nitrosylated protein, lipidperoxidation markers 4-HNE and MDA were determined in PYS-2 cells exposed to 5 mM glucose or high glucose (25 mM) with or without SOD1 (copper zinc superoxide dismutase 1) treatment. Levels of iNOS protein and mRNA, nitrosylated protein, and cleaved caspase-3 and -8 were assessed in wild-type embryos and SOD1 overexpressing embryos from non-diabetic and diabetic dams. Results SOD1 treatment diminished high glucose-induced oxidative stress, as evidenced by 4-HNE and MDA reductions, and it blocked high glucose-increased iNOS expression, iNOS-luciferase activities, and nitrosylated protein. in vivo SOD1 overexpression suppressed hyperglycemia-increased iNOS expression and nitrosylated protein, and it blocked caspase-3 and -8 cleavage. Conclusions We conclude that oxidative stress induces iNOS expression, nitrosative stress, and apoptosis in diabetic embryopathy. PMID:22425406

SOD1 suppresses maternal hyperglycemia-increased iNOS expression and consequent nitrosative stress in diabetic embryopathy.

PubMed

Weng, Hongbo; Li, Xuezheng; Reece, E Albert; Yang, Peixin

2012-05-01

Hyperglycemia induces oxidative stress and increases inducible nitric oxide synthase (iNOS) expression. We hypothesized that oxidative stress is responsible for hyperglycemia-induced iNOS expression. iNOS-luciferase activities, nitrosylated protein, and lipid peroxidation markers 4-hydroxynonenal and malondialdehyde were determined in parietal yolk sac-2 cells exposed to 5 mmol/L glucose or high glucose (25 mmol/L) with or without copper zinc superoxide dismutase 1 (SOD1) treatment. Levels of iNOS protein and messenger RNA, nitrosylated protein, and cleaved caspase-3 and -8 were assessed in wild-type embryos and SOD1-overexpressing embryos from nondiabetic and diabetic dams. SOD1 treatment diminished high glucose-induced oxidative stress, as evidenced by 4-hydroxynonenal and malondialdehyde reductions, and it blocked high glucose-increased iNOS expression, iNOS-luciferase activities, and nitrosylated protein. In vivo SOD1 overexpression suppressed hyperglycemia-increased iNOS expression and nitrosylated protein, and it blocked caspase-3 and -8 cleavage. We conclude that oxidative stress induces iNOS expression, nitrosative stress, and apoptosis in diabetic embryopathy. Copyright © 2012 Mosby, Inc. All rights reserved.

Reliability and validity of the student stress inventory-stress manifestations questionnaire and its association with personal and academic factors in university students.

PubMed

Simonelli-Muñoz, Agustín J; Balanza, Serafín; Rivera-Caravaca, José Miguel; Vera-Catalán, Tomás; Lorente, Ana María; Gallego-Gómez, Juana I

2018-05-01

Stress affects us in every environment and it is also present in the educational sphere. Previous studies have reported a high prevalence of stress in university students. The Student Stress Inventory-Stress Manifestations (SSI-SM), identify stressors and evaluate stress manifestations in adolescents but its validity in university students remains uncertain. We aimed to determine the internal consistency and validity of an adapted version of the Student Stress Inventory-Stress Manifestations (SSI-SM) for university students and to investigate if high stress levels are associated with personal and academic factors. In this quantitative, descriptive, cross-sectional study, we included 115 university students of the Nursing Degree during the second semester of the 2014/2015 academic year. Information about personal issues, lifestyle and academic performance was recorded and the stress was evaluated with the SSI-SM questionnaire. The internal consistency and homogeneity of the SSI-SM questionnaire was tested and a factorial analysis was performed. After the homogeneity analysis, the final version of the SSI-SM questionnaire included 19 items, with a Cronbach's alpha of 0.924. In the factorial analysis, 4 factors were found ('Self-concept', 'Sociability', 'Uncertainty' and 'Somatization'; all Cronbach's alpha >0.700). Students with higher values on the SSI-SM were, in overall, women (41.0 ± 12.7 vs. 33.2 ± 9.5; p = 0.001) and had significantly more family conflicts (47.6 ± 13.8 vs. 35.2 ± 9.6; p < 0.001), consumed less alcohol (R = -0.184, p = 0.048), slept less hours (R = -0.193, p = 0.038) and had worse academic performance in Clinical Nursing (36.3 ± 10.4 vs. 41.2 ± 13.3, p = 0.039). After exclude three items of the original SSI-SM, higher scores in the SSI-SM are correlated with stress level in a cohort of university students of the Nursing Degree. Family conflicts, female gender, absence of alcohol consumption, few sleep hours and poor academic performance are associated with higher stress levels. Copyright © 2018 Elsevier Ltd. All rights reserved.

Mental Health in Higher Education: A Comparative Stress Risk Assessment at an Open Distance Learning University in South Africa

ERIC Educational Resources Information Center

Poalses, Jacolize; Bezuidenhout, Adéle

2018-01-01

Universities depend on committed efforts of all staff members to function effectively. However, where occupational demands outweigh occupational resources, challenging work becomes stressful, followed by an exhausted, disengaged workforce. It is unlikely that disengaged university staff will provide adequate care and service to geographically…

Vascular Nox (NADPH Oxidase) Compartmentalization, Protein Hyperoxidation, and Endoplasmic Reticulum Stress Response in Hypertension.

PubMed

Camargo, Livia L; Harvey, Adam P; Rios, Francisco J; Tsiropoulou, Sofia; Da Silva, Renée de Nazaré Oliveira; Cao, Zhenbo; Graham, Delyth; McMaster, Claire; Burchmore, Richard J; Hartley, Richard C; Bulleid, Neil; Montezano, Augusto C; Touyz, Rhian M

2018-07-01

Vascular Nox (NADPH oxidase)-derived reactive oxygen species and endoplasmic reticulum (ER) stress have been implicated in hypertension. However, relationships between these processes are unclear. We hypothesized that Nox isoforms localize in a subcellular compartment-specific manner, contributing to oxidative and ER stress, which influence the oxidative proteome and vascular function in hypertension. Nox compartmentalization (cell fractionation), O 2 - (lucigenin), H 2 O 2 (amplex red), reversible protein oxidation (sulfenylation), irreversible protein oxidation (protein tyrosine phosphatase, peroxiredoxin oxidation), and ER stress (PERK [protein kinase RNA-like endoplasmic reticulum kinase], IRE1α [inositol-requiring enzyme 1], and phosphorylation/oxidation) were studied in spontaneously hypertensive rat (SHR) vascular smooth muscle cells (VSMCs). VSMC proliferation was measured by fluorescence-activated cell sorting, and vascular reactivity assessed in stroke-prone SHR arteries by myography. Noxs were downregulated by short interfering RNA and pharmacologically. In SHR, Noxs were localized in specific subcellular regions: Nox1 in plasma membrane and Nox4 in ER. In SHR, oxidative stress was associated with increased protein sulfenylation and hyperoxidation of protein tyrosine phosphatases and peroxiredoxins. Inhibition of Nox1 (NoxA1ds), Nox1/4 (GKT137831), and ER stress (4-phenylbutyric acid/tauroursodeoxycholic acid) normalized SHR vascular reactive oxygen species generation. GKT137831 reduced IRE1α sulfenylation and XBP1 (X-box binding protein 1) splicing in SHR. Increased VSMC proliferation in SHR was normalized by GKT137831, 4-phenylbutyric acid, and STF083010 (IRE1-XBP1 disruptor). Hypercontractility in the stroke-prone SHR was attenuated by 4-phenylbutyric acid. We demonstrate that protein hyperoxidation in hypertension is associated with oxidative and ER stress through upregulation of plasmalemmal-Nox1 and ER-Nox4. The IRE1-XBP1 pathway of the ER stress response is regulated by Nox4/reactive oxygen species and plays a role in the hyperproliferative VSMC phenotype in SHR. Our study highlights the importance of Nox subcellular compartmentalization and interplay between cytoplasmic reactive oxygen species and ER stress response, which contribute to the VSMC oxidative proteome and vascular dysfunction in hypertension. © 2018 American Heart Association, Inc.

Dietary intake and the dynamics of stress, hypertension and obesity in a peri-urban community in Accra.

PubMed

Mohammed, Husein; Ghosh, Shibani; Vuvor, Fred; Mensah-Armah, Seth; Steiner-Asiedu, Matilda

2016-03-01

This study intends to investigate the association between dietary intake, stress and prevalence of chronic diseases. The study was a cross-sectional design conducted in two poor peri-urban communities in Accra. A total of 90 households each with a male and female between the ages of 18 and 45 years were sampled, and their socio-demographic status, anthropometric measurement and fasting blood sugar were assessed. Blood pressure was measured and chronic stress/anxiety was determined using the trait and state inventory (T-stai) questionnaire. Three days repeated 24-hour dietary recall was also done. Analysis of variance and linear regression analysis were used in data analysis. About 28% of the subjects were hypertensive and 55.5% had high chronic stress. Hypertension was higher in males (32.2%) than females (24.4%) (p=.023) whiles stress was higher in females (60.9%) than males (50.0%) (p=.017). Hypertensive subjects recorded higher stress (51.02%) and hypertension was more prevalent in subjects with high stress (32.89%) especially in females (57.14%, p=.036). Hypertension increased with mean age whiles stress decreased with mean age. Hypertensive subjects recorded a significantly higher BMI and sodium intake whiles high stress individuals recorded a lower animal protein but a higher cereal protein intake (p<.05). Chronic stress was associated with intake of low animal protein and high cereal protein. Increased dietary diversity score was associated with decreased obesity prevalence (p<.05). Hypertension, chronic stress, and obesity were linked, and affected by dietary sodium, animal protein, and dietary diversity of subjects respectively.

Membrane Stored Curvature Elastic Stress Modulates Recruitment of Maintenance Proteins PspA and Vipp1

PubMed Central

McDonald, Christopher; Jovanovic, Goran; Ces, Oscar

2015-01-01

ABSTRACT Phage shock protein A (PspA), which is responsible for maintaining inner membrane integrity under stress in enterobacteria, and vesicle-inducting protein in plastids 1 (Vipp1), which functions for membrane maintenance and thylakoid biogenesis in cyanobacteria and plants, are similar peripheral membrane-binding proteins. Their homologous N-terminal amphipathic helices are required for membrane binding; however, the membrane features recognized and required for expressing their functionalities have remained largely uncharacterized. Rigorously controlled, in vitro methodologies with lipid vesicles and purified proteins were used in this study and provided the first biochemical and biophysical characterizations of membrane binding by PspA and Vipp1. Both proteins are found to sense stored curvature elastic (SCE) stress and anionic lipids within the membrane. PspA has an enhanced sensitivity for SCE stress and a higher affinity for the membrane than Vipp1. These variations in binding may be crucial for some of the proteins’ differing roles in vivo. Assays probing the transcriptional regulatory function of PspA in the presence of vesicles showed that a relief of transcription inhibition occurs in an SCE stress-specific manner. This in vitro recapitulation of membrane stress-dependent transcription control suggests that the Psp response may be mounted in vivo when a cell’s inner membrane experiences increased SCE stress. PMID:26330516

CHIP, a carboxy terminus HSP-70 interacting protein, prevents cell death induced by endoplasmic reticulum stress in the central nervous system.

PubMed

Cabral Miranda, Felipe; Adão-Novaes, Juliana; Hauswirth, William W; Linden, Rafael; Petrs-Silva, Hilda; Chiarini, Luciana B

2014-01-01

Endoplasmic reticulum (ER) stress and protein misfolding are associated with various neurodegenerative diseases. ER stress activates unfolded protein response (UPR), an adaptative response. However, severe ER stress can induce cell death. Here we show that the E3 ubiquitin ligase and co-chaperone Carboxyl Terminus HSP70/90 Interacting Protein (CHIP) prevents neuron death in the hippocampus induced by severe ER stress. Organotypic hippocampal slice cultures (OHSCs) were exposed to Tunicamycin, a pharmacological ER stress inducer, to trigger cell death. Overexpression of CHIP was achieved with a recombinant adeno-associated viral vector (rAAV) and significantly diminished ER stress-induced cell death, as shown by analysis of propidium iodide (PI) uptake, condensed chromatin, TUNEL and cleaved caspase 3 in the CA1 region of OHSCs. In addition, overexpression of CHIP prevented upregulation of both CHOP and p53 both pro-apoptotic pathways induced by ER stress. We also detected an attenuation of eIF2a phosphorylation promoted by ER stress. However, CHIP did not prevent upregulation of BiP/GRP78 induced by UPR. These data indicate that overexpression of CHIP attenuates ER-stress death response while maintain ER stress adaptative response in the central nervous system. These results indicate a neuroprotective role for CHIP upon UPR signaling. CHIP emerge as a candidate for clinical intervention in neurodegenerative diseases associated with ER stress.

Redox markers for drought-induced nodule senescence, a process occurring after drought-induced senescence of the lowest leaves in soybean (Glycine max).

PubMed

Marquez-Garcia, Belén; Shaw, Daniel; Cooper, James William; Karpinska, Barbara; Quain, Marian Dorcas; Makgopa, Eugene Matome; Kunert, Karl; Foyer, Christine Helen

2015-09-01

Water is an increasingly scarce resource that limits crop productivity in many parts of the world, and the frequency and severity of drought are predicted to increase as a result of climate change. Improving tolerance to drought stress is therefore important for maximizing future crop yields. The aim of this study was to compare the effects of drought on soybean (Glycine max) leaves and nodules in order to define phenotypic markers and changes in cellular redox state that characterize the stress response in different organs, and to characterize the relationships between leaf and nodule senescence during drought. Leaf and crown nodule metabolite pools were measured together with leaf and soil water contents, and leaf chlorophyll, total protein contents and chlorophyll a fluorescence quenching parameters in nodulated soybeans that were grown under either well-watered conditions or deprived of water for up to 21 d. Ureides, ascorbate, protein, chlorophyll and the ratios of variable chlorophyll a fluorescence (Fv') to maximal chlorophyll a fluorescence (Fm') fell to levels below detection in the oldest leaves after 21 d of drought. While these drought-induced responses were not observed in the youngest leaf ranks, the Fv'/Fm' ratios, pyridine nucleotide levels and the reduction state of the ascorbate pool were lower in all leaf ranks after 21 d of drought. In contrast to leaves, total nodule protein, pyridine nucleotides, ureides, ascorbate and glutathione contents increased as a result of the drought treatment. However, the nodule ascorbate pool was significantly less reduced as a result of drought. Higher levels of transcripts encoding two peroxiredoxins were detected in nodules exposed to drought stress but senescence-associated transcripts and other mRNAs encoding redox-related proteins were similar under both conditions. While the physiological impact of the drought was perceived throughout the shoot, stress-induced senescence occurred only in the oldest leaf ranks. At this stage, a number of drought-induced changes in nodule metabolites were observed but no metabolite or transcript markers of senescence could be detected. It is concluded that stress-induced senescence in the lowest leaf ranks precedes nodule senescence, suggesting that leaves of low photosynthetic capacity are sacrificed in favour of nodule nitrogen metabolism. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A systematic proteomic analysis of NaCl-stressed germinating maize seeds.

PubMed

Meng, Ling-Bo; Chen, Yi-Bo; Lu, Tian-Cong; Wang, Yue-Feng; Qian, Chun-Rong; Yu, Yang; Ge, Xuan-Liang; Li, Xiao-Hui; Wang, Bai-Chen

2014-05-01

Salt (NaCl) is a common physiological stressor of plants. To better understand how germinating seeds respond to salt stress, we examined the changes that occurred in the proteome of maize seeds during NaCl-treated germination. Phenotypically, salt concentrations less than 0.2 M appear to delay germination, while higher concentrations disrupt development completely, leading to seed death. The identities of 96 proteins with expression levels altered by NaCl-incubation were established using 2-DE-MALDI-TOF-MS and 2-DE-MALDI-TOF-MS/MS. Of these 96 proteins, 79 were altered greater than twofold when incubated with a 0.2 M salt solution, while 51 were altered when incubated with a 0.1 M salt solution. According to their functional annotations in the Swiss-Prot protein-sequence databases, these proteins are mainly involved in seed storage, energy metabolism, stress response, and protein metabolism. Notably, the expression of proteins that respond to abscisic acid signals increased in response to salt stress. The results of this study provide important clues as to how NaCl stresses the physiology of germinating maize seeds.

HACE1-dependent protein degradation provides cardiac protection in response to haemodynamic stress

NASA Astrophysics Data System (ADS)

Zhang, Liyong; Chen, Xin; Sharma, Parveen; Moon, Mark; Sheftel, Alex D.; Dawood, Fayez; Nghiem, Mai P.; Wu, Jun; Li, Ren-Ke; Gramolini, Anthony O.; Sorensen, Poul H.; Penninger, Josef M.; Brumell, John H.; Liu, Peter P.

2014-03-01

The HECT E3 ubiquitin ligase HACE1 is a tumour suppressor known to regulate Rac1 activity under stress conditions. HACE1 is increased in the serum of patients with heart failure. Here we show that HACE1 protects the heart under pressure stress by controlling protein degradation. Hace1 deficiency in mice results in accelerated heart failure and increased mortality under haemodynamic stress. Hearts from Hace1-/- mice display abnormal cardiac hypertrophy, left ventricular dysfunction, accumulation of LC3, p62 and ubiquitinated proteins enriched for cytoskeletal species, indicating impaired autophagy. Our data suggest that HACE1 mediates p62-dependent selective autophagic turnover of ubiquitinated proteins by its ankyrin repeat domain through protein-protein interaction, which is independent of its E3 ligase activity. This would classify HACE1 as a dual-function E3 ligase. Our finding that HACE1 has a protective function in the heart in response to haemodynamic stress suggests that HACE1 may be a potential diagnostic and therapeutic target for heart disease.

Global Analysis of WRKY Genes and Their Response to Dehydration and Salt Stress in Soybean.

PubMed

Song, Hui; Wang, Pengfei; Hou, Lei; Zhao, Shuzhen; Zhao, Chuanzhi; Xia, Han; Li, Pengcheng; Zhang, Ye; Bian, Xiaotong; Wang, Xingjun

2016-01-01

WRKY proteins are plant specific transcription factors involved in various developmental and physiological processes, especially in biotic and abiotic stress resistance. Although previous studies suggested that WRKY proteins in soybean (Glycine max var. Williams 82) involved in both abiotic and biotic stress responses, the global information of WRKY proteins in the latest version of soybean genome (Wm82.a2v1) and their response to dehydration and salt stress have not been reported. In this study, we identified 176 GmWRKY proteins from soybean Wm82.a2v1 genome. These proteins could be classified into three groups, namely group I (32 proteins), group II (120 proteins), and group III (24 proteins). Our results showed that most GmWRKY genes were located on Chromosome 6, while chromosome 11, 12, and 20 contained the least number of this gene family. More GmWRKY genes were distributed on the ends of chromosomes to compare with other regions. The cis-acting elements analysis suggested that GmWRKY genes were transcriptionally regulated upon dehydration and salt stress. RNA-seq data analysis indicated that three GmWRKY genes responded negatively to dehydration, and 12 genes positively responded to salt stress at 1, 6, and 12 h, respectively. We confirmed by qRT-PCR that the expression of GmWRKY47 and GmWRKY 58 genes was decreased upon dehydration, and the expression of GmWRKY92, 144 and 165 genes was increased under salt treatment.

STRESS PROTEINS IN AQUATIC ORGANISMS: AN ENVIRONMENTAL PERSPECTIVE

EPA Science Inventory

The cellular stress response protects organisms from damage resulting from exposure to a wide variety of stressors, including elevated temperatures, ultraviolet (UV) light, trace metals, and xenobiotics. he stress response entails the rapid synthesis of a suite of proteins referr...

The ER stress sensor PERK luminal domain functions as a molecular chaperone to interact with misfolded proteins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Peng; Li, Jingzhi; Sha, Bingdong

2016-11-29

PERK is one of the major sensor proteins which can detect the protein-folding imbalance generated by endoplasmic reticulum (ER) stress. It remains unclear how the sensor protein PERK is activated by ER stress. It has been demonstrated that the PERK luminal domain can recognize and selectively interact with misfolded proteins but not native proteins. Moreover, the PERK luminal domain may function as a molecular chaperone to directly bind to and suppress the aggregation of a number of misfolded model proteins. The data strongly support the hypothesis that the PERK luminal domain can interact directly with misfolded proteins to induce ERmore » stress signaling. To illustrate the mechanism by which the PERK luminal domain interacts with misfolded proteins, the crystal structure of the human PERK luminal domain was determined to 3.2 Å resolution. Two dimers of the PERK luminal domain constitute a tetramer in the asymmetric unit. Superimposition of the PERK luminal domain molecules indicated that the β-sandwich domain could adopt multiple conformations. It is hypothesized that the PERK luminal domain may utilize its flexible β-sandwich domain to recognize and interact with a broad range of misfolded proteins.« less

The ER stress sensor PERK luminal domain functions as a molecular chaperone to interact with misfolded proteins.

PubMed

Wang, Peng; Li, Jingzhi; Sha, Bingdong

2016-12-01

PERK is one of the major sensor proteins which can detect the protein-folding imbalance generated by endoplasmic reticulum (ER) stress. It remains unclear how the sensor protein PERK is activated by ER stress. It has been demonstrated that the PERK luminal domain can recognize and selectively interact with misfolded proteins but not native proteins. Moreover, the PERK luminal domain may function as a molecular chaperone to directly bind to and suppress the aggregation of a number of misfolded model proteins. The data strongly support the hypothesis that the PERK luminal domain can interact directly with misfolded proteins to induce ER stress signaling. To illustrate the mechanism by which the PERK luminal domain interacts with misfolded proteins, the crystal structure of the human PERK luminal domain was determined to 3.2 Å resolution. Two dimers of the PERK luminal domain constitute a tetramer in the asymmetric unit. Superimposition of the PERK luminal domain molecules indicated that the β-sandwich domain could adopt multiple conformations. It is hypothesized that the PERK luminal domain may utilize its flexible β-sandwich domain to recognize and interact with a broad range of misfolded proteins.

Organ Specific Proteomic Dissection of Selaginella bryopteris Undergoing Dehydration and Rehydration

PubMed Central

Deeba, Farah; Pandey, Ashutosh K.; Pandey, Vivek

2016-01-01

To explore molecular mechanisms underlying the physiological response of Selaginella bryopteris, a comprehensive proteome analysis was carried out in roots and fronds undergoing dehydration and rehydration. Plants were dehydrated for 7 days followed by 2 and 24 h of rehydration. In roots out of 59 identified spots, 58 protein spots were found to be up-regulated during dehydration stress. The identified proteins were related to signaling, stress and defense, protein and nucleotide metabolism, carbohydrate and energy metabolism, storage and epigenetic control. Most of these proteins remained up-regulated on first rehydration, suggesting their role in recovery phase also. Among the 90 identified proteins in fronds, about 49% proteins were up-regulated during dehydration stress. Large number of ROS scavenging proteins was enhanced on dehydration. Many other proteins involved in energy, protein turnover and nucleotide metabolism, epigenetic control were also highly upregulated. Many photosynthesis related proteins were upregulated during stress. This would have helped plant to recover rapidly on rehydration. This study provides a comprehensive picture of different cellular responses elucidated by the proteome changes during dehydration and rehydration in roots and fronds as expected from a well-choreographed response from a resurrection plant. PMID:27092152

Differential correlations between changes to glutathione redox state, protein ubiquitination, and stress-inducible HSPA chaperone expression after different types of oxidative stress.

PubMed

Girard, Pierre-Marie; Peynot, Nathalie; Lelièvre, Jean-Marc

2018-05-12

In primary bovine fibroblasts with an hspa1b/luciferase transgene, we examined the intensity of heat-shock response (HSR) following four types of oxidative stress or heat stress (HS), and its putative relationship with changes to different cell parameters, including reactive oxygen species (ROS), the redox status of the key molecules glutathione (GSH), NADP(H) NAD(H), and the post-translational protein modifications carbonylation, S-glutathionylation, and ubiquitination. We determined the sub-lethal condition generating the maximal luciferase activity and inducible HSPA protein level for treatments with hydrogen peroxide (H 2 O 2 ), UVA-induced oxygen photo-activation, the superoxide-generating agent menadione (MN), and diamide (DA), an electrophilic and sulfhydryl reagent. The level of HSR induced by oxidative stress was the highest after DA and MN, followed by UVA and H 2 O 2 treatments, and was not correlated to the level of ROS production nor to the extent of protein S-glutathionylation or carbonylation observed immediately after stress. We found a correlation following oxidative treatments between HSR and the level of GSH/GSSG immediately after stress, and the increase in protein ubiquitination during the recovery period. Conversely, HS treatment, which led to the highest HSR level, did not generate ROS nor modified or depended on GSH redox state. Furthermore, the level of protein ubiquitination was maximum immediately after HS and lower than after MN and DA treatments thereafter. In these cells, heat-induced HSR was therefore clearly different from oxidative stress-induced HSR, in which conversely early redox changes of the major cellular thiol predicted the level of HSR and polyubiquinated proteins.

Stressors and reactions to stressors among university students.

PubMed

Hamaideh, Shaher H

2011-01-01

University students are prone to stressors due to the transitional nature of university life. High levels of stress are believed to affect students' health as well as their academic performance. The aims of this study were to identify stressors and reactions to stressors among university students, and to examine the correlations between student stressors and study variables. A correlational descriptive design was used. Student-life Stress Inventory (SSI) was used to measure the stressors and reactions to stressors. Stratified random sampling was employed to recruit participants. The final sample consisted of 877 participants (students). s indicated that the highest group of stressors experienced by students were 'self-imposed' stressors followed by 'pressures'. Cognitive responses were found to be the highest responses to stressors experienced by students. Negative correlations were found with student's perception of health, and father's and mother's level of education. This study revealed that stressors among university students come from 'self-imposed' stressors and 'pressures'. Stress management, assertiveness skills, time management and counselling sessions will be effective in reducing stress experienced by students.

Protein Network Signatures Associated with Exogenous Biofuels Treatments in Cyanobacterium Synechocystis sp. PCC 6803

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pei, Guangsheng; Chen, Lei; Wang, Jiangxin

2014-11-03

Although recognized as a promising microbial cell factory for producing biofuels, current productivity in cyanobacterial systems is low. To make the processes economically feasible, one of the hurdles, which need to be overcome is the low tolerance of hosts to toxic biofuels. Meanwhile, little information is available regarding the cellular responses to biofuels stress in cyanobacteria, which makes it challenging for tolerance engineering. Using large proteomic datasets of Synechocystis under various biofuels stress and environmental perturbation, a protein co-expression network was first constructed and then combined with the experimentally determined protein–protein interaction network. Proteins with statistically higher topological overlap inmore » the integrated network were identified as common responsive proteins to both biofuels stress and environmental perturbations. In addition, a weighted gene co-expression network analysis was performed to distinguish unique responses to biofuels from those to environmental perturbations and to uncover metabolic modules and proteins uniquely associated with biofuels stress. The results showed that biofuel-specific proteins and modules were enriched in several functional categories, including photosynthesis, carbon fixation, and amino acid metabolism, which may represent potential key signatures for biofuels stress responses in Synechocystis. Network-based analysis allowed determination of the responses specifically related to biofuels stress, and the results constituted an important knowledge foundation for tolerance engineering against biofuels in Synechocystis.« less

Light Stress-Induced One-Helix Protein of the Chlorophyll a/b-Binding Family Associated with Photosystem I1

PubMed Central

Andersson, Ulrica; Heddad, Mounia; Adamska, Iwona

2003-01-01

The superfamily of light-harvesting chlorophyll a/b-binding (Lhc) proteins in higher plants and green algae is composed of more than 20 different antenna proteins associated either with photosystem I (PSI) or photosystem II (PSII). Several distant relatives of this family with conserved chlorophyll-binding residues and proposed photoprotective functions are induced transiently under various stress conditions. Whereas “classical” Lhc proteins contain three-transmembrane α-helices, their distant relatives span the membrane with between one and four transmembrane segments. Here, we report the identification and isolation of a novel member of the Lhc family from Arabidopsis with one predicted transmembrane α-helix closely related to helix I of Lhc protein from PSI (Lhca4) that we named Ohp2 (for a second one-helix protein of Lhc family described from higher plants). We showed that the Ohp2 gene expression is triggered by light stress and that the Ohp2 transcript and protein accumulated in a light intensity-dependent manner. Other stress conditions did not up-regulate the expression of the Ohp2 gene. Localization studies revealed that Ohp2 is associated with PSI under low- or high-light conditions. Because all stress-induced Lhc relatives reported so far were found in PSII, we propose that the accumulation of Ohp2 might represent a novel photoprotective strategy induced within PSI in response to light stress. PMID:12805611

Comparative proteomic analysis of Listeria monocytogenes exposed to enterocin AS-48 in planktonic and sessile states.

PubMed

Caballero Gómez, Natacha; Abriouel, Hikmate; Ennahar, Said; Gálvez, Antonio

2013-10-15

Enterocin AS-48 is a cyclic peptide of great interest for application in food preservation and sanitation. In the present study, the proteome response of Listeria monocytogenes to purified enterocin AS-48 was studied under two different conditions: planktonic cells and sessile cells grown on polystyrene plates. Ten different proteins were differentially expressed in planktonic L. monocytogenes cells treated with 0.1 μg/ml enterocin AS-48 compared to the untreated controls. Overexpressed proteins were related to stress response (DnaK) or carbohydrate transport and metabolism, while underexpressed and unexpressed proteins were related to metabolism (such as glyceraldehyde-3-phosphate dehydrogenase, pyruvate oxidase, glutamate dehydrogenase or glutamate decarboxylase) or stress (GroEL). In the sessile state, L. monocytogenes cells tolerated up to 10 μg/ml bacteriocin, and the treated biofilm cells overexpressed a set of 11 proteins, some of which could be related to stress response (DnaK, GroEL), protein synthesis and carbohydrate metabolism, while glyceraldehyde-3-phosphate dehydrogenase was the only unexpressed protein. Some of the overexpressed proteins (such as elongation factor Tu and GroEL) could also be implicated in cell adhesion. These results suggest different cell responses of L. monocytogenes to enterocin AS-48 in the planktonic and in the sessile state, including stress response and cell metabolism proteins. While in the planktonic state the bacterium may tend to compensate for the cytoplasmic cell permeability changes induced by AS-48 by reinforcing carbohydrate transport and metabolism, sessile cells seem to respond by shifting carbohydrate metabolism and reinforcing protein synthesis. Stress response proteins also seem to be important in the response to AS-48, but the stress response seems to be different in planktonic and in sessile cells. © 2013.

Dynamic changes in saliva after acute mental stress

PubMed Central

Naumova, Ella A.; Sandulescu, Tudor; Bochnig, Clemens; Khatib, Philipp Al; Lee, Wing-Kee; Zimmer, Stefan; Arnold, Wolfgang H.

2014-01-01

Stress-related variations of fluoride concentration in supernatant saliva and salivary sediment, salivary cortisol, total protein and pH after acute mental stress were assessed. The hypothesis was that stress reactions have no influence on these parameters. Thirty-four male students were distributed into two groups: first received the stress exposure followed by the same protocol two weeks later but without stress exposure, second underwent the protocol without stress exposure followed by the stress exposure two weeks later. The stressor was a public speech followed by tooth brushing. Saliva was collected before, immediately after stress induction and immediately, at 10, 30 and 120 min. after tooth brushing. Cortisol concentrations, total protein, intraoral pH, and fluoride content in saliva were measured. The data were analyzed statistically. Salivary sediment was ca 4.33% by weight of whole unstimulated saliva. Fluoride bioavailability was higher in salivary sediment than in supernatant saliva. The weight and fluoride concentration was not altered during 2 hours after stress exposure. After a public speech, the salivary cortisol concentration significantly increased after 20 minutes compared to the baseline. The salivary protein concentration and pH also increased. Public speaking influences protein concentration and salivary pH but does not alter the fluoride concentration of saliva. PMID:24811301

P-body proteins regulate transcriptional rewiring to promote DNA replication stress resistance.

PubMed

Loll-Krippleber, Raphael; Brown, Grant W

2017-09-15

mRNA-processing (P-) bodies are cytoplasmic granules that form in eukaryotic cells in response to numerous stresses to serve as sites of degradation and storage of mRNAs. Functional P-bodies are critical for the DNA replication stress response in yeast, yet the repertoire of P-body targets and the mechanisms by which P-bodies promote replication stress resistance are unknown. In this study we identify the complete complement of mRNA targets of P-bodies during replication stress induced by hydroxyurea treatment. The key P-body protein Lsm1 controls the abundance of HHT1, ACF4, ARL3, TMA16, RRS1 and YOX1 mRNAs to prevent their toxic accumulation during replication stress. Accumulation of YOX1 mRNA causes aberrant downregulation of a network of genes critical for DNA replication stress resistance and leads to toxic acetaldehyde accumulation. Our data reveal the scope and the targets of regulation by P-body proteins during the DNA replication stress response.P-bodies form in response to stress and act as sites of mRNA storage and degradation. Here the authors identify the mRNA targets of P-bodies during DNA replication stress, and show that P-body proteins act to prevent toxic accumulation of these target transcripts.

Triticum aestivum WRAB18 functions in plastids and confers abiotic stress tolerance when overexpressed in Escherichia coli and Nicotiania benthamiana.

PubMed

Wang, Xiaoyu; Zhang, Linsheng; Zhang, Yane; Bai, Zhenqing; Liu, Hao; Zhang, Dapeng

2017-01-01

WRAB18, an ABA-inducible protein belongs to the third family of late embryogenesis abundant (LEA) proteins which can be induced by different biotic or abiotic stresses. In the present study, WRAB18 was cloned from the Zhengyin 1 cultivar of Triticum aestivum and overexpressed in Escherichia coli to explore its effects on the growth of E. coli under different abiotic stresses. Results suggested the enhanced exhibition of tolerance of E. coli to these stresses. Meanwhile, the WRAB18-transgenic tobacco plants were obtained to analyze the stress-related enzymatic activities of ascorbate peroxidase (APX), peroxidase (POD) and superoxide dismutase (SOD), and to quantify the content of malonaldehyde (MDA) under osmotic stress, high salinity, and low and high temperature stress. The activities of APX, POD and SOD in the transgenic tobacco lines were higher while the content of MDA was lower than those of WT lines. Moreover, plastid localization of WRAB18 in Nicotiana benthamiana plasma cells were found fusing with GFP. In addition, purified WRAB18 protein protected LDH (Lactate dehydrogenase) enzyme activity in vitro from various stress conditions. In brief, WRAB18 protein shows protective action behaving as a "molecular shield" in both prokaryotic and eukaryotic cells under various abiotic stresses, not only during ABA stress.

Relationships among Perceived Stress, Coping, and Grade Point Average in University Students

ERIC Educational Resources Information Center

Kewallal, Rajendra David

2013-01-01

This study explored the relationships among perceived stress, coping style, and academic performance in 210 students from a mid-sized public university and a small private college. Study participants were asked to complete the Perceived Stress Scale, the Brief COPE Questionnaire, and a demographic survey asking about their age, gender, grade point…

Faculty Perception of Stress and Coping Strategies in a Saudi Private University: An Exploratory Study

ERIC Educational Resources Information Center

Iqbal, Adnan; Kokash, Husam

2011-01-01

Teaching profession was once viewed as a "low stress occupation" and they have been envied for tenure, light workloads, flexibility and other perks such as foreign trips for study and conference. However, some recent studies suggest that university faculty is among the most stressed occupational group. The present study was conducted to…

Workload and Stress in New Zealand Universities. A Follow Up to the 1994 Study.

ERIC Educational Resources Information Center

Chalmers, Anna

This follow-up study surveyed members of the Association of University Staff of New Zealand concerning their workload and stress levels and compared findings to a similar survey conducted in 1994. Survey responses (n=1155) were analyzed in terms of employment status, work hours, salary, responsibilities, changes and their impact, stresses and…

Quinone-induced protein handling changes: Implications for major protein handling systems in quinone-mediated toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiong, Rui; Siegel, David; Ross, David, E-mail: david.ross@ucdenver.edu

2014-10-15

Para-quinones such as 1,4-Benzoquinone (BQ) and menadione (MD) and ortho-quinones including the oxidation products of catecholamines, are derived from xenobiotics as well as endogenous molecules. The effects of quinones on major protein handling systems in cells; the 20/26S proteasome, the ER stress response, autophagy, chaperone proteins and aggresome formation, have not been investigated in a systematic manner. Both BQ and aminochrome (AC) inhibited proteasomal activity and activated the ER stress response and autophagy in rat dopaminergic N27 cells. AC also induced aggresome formation while MD had little effect on any protein handling systems in N27 cells. The effect of NQO1more » on quinone induced protein handling changes and toxicity was examined using N27 cells stably transfected with NQO1 to generate an isogenic NQO1-overexpressing line. NQO1 protected against BQ–induced apoptosis but led to a potentiation of AC- and MD-induced apoptosis. Modulation of quinone-induced apoptosis in N27 and NQO1-overexpressing cells correlated only with changes in the ER stress response and not with changes in other protein handling systems. These data suggested that NQO1 modulated the ER stress response to potentiate toxicity of AC and MD, but protected against BQ toxicity. We further demonstrated that NQO1 mediated reduction to unstable hydroquinones and subsequent redox cycling was important for the activation of the ER stress response and toxicity for both AC and MD. In summary, our data demonstrate that quinone-specific changes in protein handling are evident in N27 cells and the induction of the ER stress response is associated with quinone-mediated toxicity. - Highlights: • Unstable hydroquinones contributed to quinone-induced ER stress and toxicity.« less

Identification of novel transcriptional regulators of Zat12 using comprehensive yeast one-hybrid screens.

PubMed

Ben Daniel, Bat-Hen; Cattan, Esther; Wachtel, Chaim; Avrahami, Dorit; Glick, Yair; Malichy, Asaf; Gerber, Doron; Miller, Gad

2016-08-01

To appropriately acclimate to environmental stresses, plants have to rapidly activate a specific transcriptional program. Yet, the identity and function of many of the transcriptional regulators that mediate early responses to abiotic stress stimuli is still unknown. In this work we employed the promoter of the multi-stress-responsive zinc-finger protein Zat12 in yeast one-hybrid (Y1H) screens to identify early abiotic stress-responsive transcriptional regulators. Analysis of Zat12 promoter fragments fused to luciferase underlined an approximately 200 bp fragment responsive to NaCl and to reactive oxygen species (ROS). Using these segments and others as baits against Y1H control or stress Arabidopsis prey libraries, we identified 15 potential Zat12 transcriptional regulators. Among the prominent proteins identified were known transcription factors including bZIP29 and ANAC91 as well as unknown function proteins such as a homolog of the human USB1, a U6 small nuclear RNA (snRNA) processing protein, and dormancy/auxin-associated family protein 2 (DRM2). Altered expression of Zat12 during high light stress in the knockout mutants further indicated the involvement of these proteins in the regulation of Zat12. Using a state of the art microfluidic approach we showed that AtUSB1 and DRM2 can specifically bind dsDNA and were able to identify the preferred DNA-binding motif of all four proteins. Overall, the proteins identified in this work provide an important start point for charting the earliest signaling network of Zat12 and of other genes required for acclimation to abiotic stresses. © 2016 Scandinavian Plant Physiology Society.

Sarcomeric protein modification during adrenergic stress enhances cross-bridge kinetics and cardiac output

PubMed Central

Gresham, Kenneth S.; Mamidi, Ranganath; Li, Jiayang; Kwak, Hyerin

2017-01-01

Molecular adaptations to chronic neurohormonal stress, including sarcomeric protein cleavage and phosphorylation, provide a mechanism to increase ventricular contractility and enhance cardiac output, yet the link between sarcomeric protein modifications and changes in myocardial function remains unclear. To examine the effects of neurohormonal stress on posttranslational modifications of sarcomeric proteins, mice were administered combined α- and β-adrenergic receptor agonists (isoproterenol and phenylephrine, IPE) for 14 days using implantable osmotic pumps. In addition to significant cardiac hypertrophy and increased maximal ventricular pressure, IPE treatment accelerated pressure development and relaxation (74% increase in dP/dtmax and 14% decrease in τ), resulting in a 52% increase in cardiac output compared with saline (SAL)-treated mice. Accelerated pressure development was maintained when accounting for changes in heart rate and preload, suggesting that myocardial adaptations contribute to enhanced ventricular contractility. Ventricular myocardium isolated from IPE-treated mice displayed a significant reduction in troponin I (TnI) and myosin-binding protein C (MyBP-C) expression and a concomitant increase in the phosphorylation levels of the remaining TnI and MyBP-C protein compared with myocardium isolated from saline-treated control mice. Skinned myocardium isolated from IPE-treated mice displayed a significant acceleration in the rate of cross-bridge (XB) detachment (46% increase) and an enhanced magnitude of XB recruitment (43% increase) at submaximal Ca2+ activation compared with SAL-treated mice but unaltered myofilament Ca2+ sensitivity of force generation. These findings demonstrate that sarcomeric protein modifications during neurohormonal stress are molecular adaptations that enhance in vivo ventricular contractility through accelerated XB kinetics to increase cardiac output. NEW & NOTEWORTHY Posttranslational modifications to sarcomeric regulatory proteins provide a mechanism to modulate cardiac function in response to stress. In this study, we demonstrate that neurohormonal stress produces modifications to myosin-binding protein C and troponin I, including a reduction in protein expression within the sarcomere and increased phosphorylation of the remaining protein, which serve to enhance cross-bridge kinetics and increase cardiac output. These findings highlight the importance of sarcomeric regulatory protein modifications in modulating ventricular function during cardiac stress. PMID:27909224

Sarcomeric protein modification during adrenergic stress enhances cross-bridge kinetics and cardiac output.

PubMed

Gresham, Kenneth S; Mamidi, Ranganath; Li, Jiayang; Kwak, Hyerin; Stelzer, Julian E

2017-03-01

Molecular adaptations to chronic neurohormonal stress, including sarcomeric protein cleavage and phosphorylation, provide a mechanism to increase ventricular contractility and enhance cardiac output, yet the link between sarcomeric protein modifications and changes in myocardial function remains unclear. To examine the effects of neurohormonal stress on posttranslational modifications of sarcomeric proteins, mice were administered combined α- and β-adrenergic receptor agonists (isoproterenol and phenylephrine, IPE) for 14 days using implantable osmotic pumps. In addition to significant cardiac hypertrophy and increased maximal ventricular pressure, IPE treatment accelerated pressure development and relaxation (74% increase in dP/d t max and 14% decrease in τ), resulting in a 52% increase in cardiac output compared with saline (SAL)-treated mice. Accelerated pressure development was maintained when accounting for changes in heart rate and preload, suggesting that myocardial adaptations contribute to enhanced ventricular contractility. Ventricular myocardium isolated from IPE-treated mice displayed a significant reduction in troponin I (TnI) and myosin-binding protein C (MyBP-C) expression and a concomitant increase in the phosphorylation levels of the remaining TnI and MyBP-C protein compared with myocardium isolated from saline-treated control mice. Skinned myocardium isolated from IPE-treated mice displayed a significant acceleration in the rate of cross-bridge (XB) detachment (46% increase) and an enhanced magnitude of XB recruitment (43% increase) at submaximal Ca 2+ activation compared with SAL-treated mice but unaltered myofilament Ca 2+ sensitivity of force generation. These findings demonstrate that sarcomeric protein modifications during neurohormonal stress are molecular adaptations that enhance in vivo ventricular contractility through accelerated XB kinetics to increase cardiac output. NEW & NOTEWORTHY Posttranslational modifications to sarcomeric regulatory proteins provide a mechanism to modulate cardiac function in response to stress. In this study, we demonstrate that neurohormonal stress produces modifications to myosin-binding protein C and troponin I, including a reduction in protein expression within the sarcomere and increased phosphorylation of the remaining protein, which serve to enhance cross-bridge kinetics and increase cardiac output. These findings highlight the importance of sarcomeric regulatory protein modifications in modulating ventricular function during cardiac stress. Copyright © 2017 the American Physiological Society.

Shared and novel molecular responses of mandarin to drought.

PubMed

Gimeno, Jacinta; Gadea, José; Forment, Javier; Pérez-Valle, Jorge; Santiago, Julia; Martínez-Godoy, María A; Yenush, Lynne; Bellés, José M; Brumós, Javier; Colmenero-Flores, José M; Talón, Manuel; Serrano, Ramón

2009-07-01

Drought is the most important stress experienced by citrus crops. A citrus cDNA microarray of about 6.000 genes has been utilized to identify transcriptomic responses of mandarin to water stress. As observed in other plant species challenged with drought stress, key genes for lysine catabolism, proline and raffinose synthesis, hydrogen peroxide reduction, vacuolar malate transport, RCI2 proteolipids and defence proteins such as osmotin, dehydrins and heat-shock proteins are induced in mandarin. Also, some aquaporin genes are repressed. The osmolyte raffinose could be detected in stressed roots while the dehydrin COR15 protein only accumulated in stressed leaves but not in roots. Novel drought responses in mandarin include the induction of genes encoding a new miraculin isoform, chloroplast beta-carotene hydroxylase, oleoyl desaturase, ribosomal protein RPS13A and protein kinase CTR1. These results suggest that drought tolerance in citrus may benefit from inhibition of proteolysis, activation of zeaxanthin and linolenoyl synthesis, reinforcement of ribosomal structure and down-regulation of the ethylene response.

Preliminary analysis of cold stress responsive proteins in Mesocestoides corti larvae.

PubMed

Canclini, Lucía; Esteves, Adriana

2007-07-01

Many parasites undergo sudden changes in environmental conditions at some stage during their life cycle. The molecular response to this variation is characterised by a rapid transcriptional activation of a specific set of genes coding for proteins generically known as stress proteins. They appear to be also involved in various biological processes including cell proliferation and differentiation. The platyhelminth parasite, Mesocestoides corti (Cestoda) presents important properties as a model organism. Under stress conditions, key molecules involved in metabolic pathways as well as in the growth and differentiation of the parasite can be identified. 2D protein expression profile of tetrathyridia of M. corti, submitted to nutritional starvation and cold stress is described, as well as the recovery pattern. A set of specifically expressed proteins was observed in each experimental condition. Quantitative and qualitative differences and stress recovery pattern are also reported. This work makes evident the high plasticity and resistance to extreme environmental conditions of these parasites at the molecular level.

Cmr1/WDR76 defines a nuclear genotoxic stress body linking genome integrity and protein quality control.

PubMed

Gallina, Irene; Colding, Camilla; Henriksen, Peter; Beli, Petra; Nakamura, Kyosuke; Offman, Judith; Mathiasen, David P; Silva, Sonia; Hoffmann, Eva; Groth, Anja; Choudhary, Chunaram; Lisby, Michael

2015-03-30

DNA replication stress is a source of genomic instability. Here we identify changed mutation rate 1 (Cmr1) as a factor involved in the response to DNA replication stress in Saccharomyces cerevisiae and show that Cmr1--together with Mrc1/Claspin, Pph3, the chaperonin containing TCP1 (CCT) and 25 other proteins--define a novel intranuclear quality control compartment (INQ) that sequesters misfolded, ubiquitylated and sumoylated proteins in response to genotoxic stress. The diversity of proteins that localize to INQ indicates that other biological processes such as cell cycle progression, chromatin and mitotic spindle organization may also be regulated through INQ. Similar to Cmr1, its human orthologue WDR76 responds to proteasome inhibition and DNA damage by relocalizing to nuclear foci and physically associating with CCT, suggesting an evolutionarily conserved biological function. We propose that Cmr1/WDR76 plays a role in the recovery from genotoxic stress through regulation of the turnover of sumoylated and phosphorylated proteins.

Rapid and Sustained Antidepressant Action of the mGlu2/3 Receptor Antagonist MGS0039 in the Social Defeat Stress Model: Comparison with Ketamine.

PubMed

Dong, Chao; Zhang, Ji-Chun; Yao, Wei; Ren, Qian; Ma, Min; Yang, Chun; Chaki, Shigeyuki; Hashimoto, Kenji

2017-03-01

Similar to the N-methyl-D-aspartate receptor antagonist ketamine, the metabotropic glutamate 2/3 receptor antagonist, MGS0039, shows antidepressant effects. However, there are no reports comparing these 2 compounds in the social defeat stress model of depression. We examined the effects of MGS0039 (1 mg/kg) and ketamine (10 mg/kg) on depression-like behavior in susceptible mice after repeated social defeat stress. Protein levels of brain-derived neurotrophic factor, TrkB, phospho-TrkB, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (GluA1), postsynaptic density protein 95, and dendritic spine density in selected brain regions were measured. In the tail suspension and forced swimming tests, both MGS0039 and ketamine significantly attenuated the increased immobility time observed in susceptible mice, compared with vehicle-treated animals, 1 or 2 days after a single dose of drug. In the sucrose preference test, both compounds significantly improved the reduced preference typically seen in susceptible mice at 3 to 7 days after a single dose of drug. Western-blot analyses showed that similar to ketamine, MGS0039 significantly attenuated the reduced brain-derived neurotrophic factor, phospho-TrkB/TrkB ratio, GluA1 and postsynaptic density protein 95 seen in the prefrontal cortex, dentate gyrus, and CA3 of the hippocampus from susceptible mice, 8 days after a single dose. Again, in a similar manner to ketamine, MGS0039 significantly attenuated the reduction of spine density in the prelimbic regions of the medial prefrontal cortex, dentate gyrus, and CA3 of the hippocampus, but not infralimbic regions of the medial prefrontal cortex and CA1, in susceptible mice 8 days after a single dose. In contrast, neither drug elicited an effect on altered brain-derived neurotrophic factor-TrkB signaling, GluA1, and postsynaptic density protein 95 levels and did not increase spine density observed in the nucleus accumbens of susceptible mice. Similar to ketamine, MGS0039 shows rapid and sustained antidepressant effects in the social defeat stress model. Long-lasting synaptogenesis in the prelimbic regions of medial prefrontal cortex, dentate gyrus, and CA3 might be implicated in this sustained antidepressant effect. © The Author 2016. Published by Oxford University Press on behalf of CINP.

Heat Shock Proteins: A Review of the Molecular Chaperones for Plant Immunity.

PubMed

Park, Chang-Jin; Seo, Young-Su

2015-12-01

As sessile organisms, plants are exposed to persistently changing stresses and have to be able to interpret and respond to them. The stresses, drought, salinity, chemicals, cold and hot temperatures, and various pathogen attacks have interconnected effects on plants, resulting in the disruption of protein homeostasis. Maintenance of proteins in their functional native conformations and preventing aggregation of non-native proteins are important for cell survival under stress. Heat shock proteins (HSPs) functioning as molecular chaperones are the key components responsible for protein folding, assembly, translocation, and degradation under stress conditions and in many normal cellular processes. Plants respond to pathogen invasion using two different innate immune responses mediated by pattern recognition receptors (PRRs) or resistance (R) proteins. HSPs play an indispensable role as molecular chaperones in the quality control of plasma membrane-resident PRRs and intracellular R proteins against potential invaders. Here, we specifically discuss the functional involvement of cytosolic and endoplasmic reticulum (ER) HSPs/chaperones in plant immunity to obtain an integrated understanding of the immune responses in plant cells.

Responses of Plant Proteins to Heavy Metal Stress—A Review

PubMed Central

Hasan, Md. Kamrul; Cheng, Yuan; Kanwar, Mukesh K.; Chu, Xian-Yao; Ahammed, Golam J.; Qi, Zhen-Yu

2017-01-01

Plants respond to environmental pollutants such as heavy metal(s) by triggering the expression of genes that encode proteins involved in stress response. Toxic metal ions profoundly affect the cellular protein homeostasis by interfering with the folding process and aggregation of nascent or non-native proteins leading to decreased cell viability. However, plants possess a range of ubiquitous cellular surveillance systems that enable them to efficiently detoxify heavy metals toward enhanced tolerance to metal stress. As proteins constitute the major workhorses of living cells, the chelation of metal ions in cytosol with phytochelatins and metallothioneins followed by compartmentalization of metals in the vacuoles as well as the repair of stress-damaged proteins or removal and degradation of proteins that fail to achieve their native conformations are critical for plant tolerance to heavy metal stress. In this review, we provide a broad overview of recent advances in cellular protein research with regards to heavy metal tolerance in plants. We also discuss how plants maintain functional and healthy proteomes for survival under such capricious surroundings. PMID:28928754

Protein Folding and the Challenges of Maintaining Endoplasmic Reticulum Proteostasis in Idiopathic Pulmonary Fibrosis.

PubMed

Romero, Freddy; Summer, Ross

2017-11-01

Alveolar epithelial type II (AEII) cells are "professional" secretory cells that synthesize and secrete massive quantities of proteins to produce pulmonary surfactant and maintain airway immune defenses. To facilitate this high level of protein synthesis, AEII cells are equipped with an elaborate endoplasmic reticulum (ER) structure and possess an abundance of the machinery needed to fold, assemble, and secrete proteins. However, conditions that suddenly increase the quantity of new proteins entering the ER or that impede the capacity of the ER to fold proteins can cause misfolded or unfolded proteins to accumulate in the ER lumen, also called ER stress. To minimize this stress, AEII cells adapt by (1) reducing the quantity of proteins entering the ER, (2) increasing the amount of protein-folding machinery, and (3) removing misfolded proteins when they accumulate. Although these adaptive responses, aptly named the unfolded protein response, are usually effective in reducing ER stress, chronic aggregation of misfolded proteins is recognized as a hallmark feature of AEII cells in patients with idiopathic pulmonary fibrosis (IPF). Although mutations in surfactant proteins are linked to the development of ER stress in some rare IPF cases, the mechanisms causing protein misfolding in most cases are unknown. In this article, we review the mechanisms regulating ER proteostasis and highlight specific aspects of protein folding and the unfolded protein response that are most vulnerable to failure. Then, we postulate mechanisms other than genetic mutations that might contribute to protein aggregation in the alveolar epithelium of IPF lung.

The Endoplasmic Reticulum Stress Protein Calreticulin in Diabetic Chronic Kidney Disease

DTIC Science & Technology

2016-07-01

AWARD NUMBER: W81XWH-14-1-0203 TITLE: The Endoplasmic Reticulum Stress Protein Calreticulin in Diabetic Chronic Kidney Disease PRINCIPAL...1 July 2015- 30 June 2016 4. TITLE AND SUBTITLE The Endoplasmic Reticulum Stress Protein Calreticulin in Diabetic Chronic Kidney Disease 5a... kidney targeted microbubble/ultrasound-mediated plasmid delivery. We will also examine non-targeted CRT knockdown in these mice. Aim 2.b: We will

Choline kinase inhibition induces exacerbated endoplasmic reticulum stress and triggers apoptosis via CHOP in cancer cells

PubMed Central

Sanchez-Lopez, E; Zimmerman, T; Gomez del Pulgar, T; Moyer, M P; Lacal Sanjuan, J C; Cebrian, A

2013-01-01

Endoplasmic reticulum (ER) is a central organelle in eukaryotic cells that regulates protein synthesis and maturation. Perturbation of ER functions leads to ER stress, which has been previously associated with a broad variety of diseases. ER stress is generally regarded as compensatory, but prolonged ER stress has been involved in apoptosis induced by several cytotoxic agents. Choline kinase α (ChoKα), the first enzyme in the Kennedy pathway, is responsible for the generation of phosphorylcholine (PCho) that ultimately renders phosphatidylcholine. ChoKα overexpression and high PCho levels have been detected in several cancer types. Inhibition of ChoKα has demonstrated antiproliferative and antitumor properties; however, the mechanisms underlying these activities remain poorly understood. Here, we demonstrate that ChoKα inhibitors (ChoKIs), MN58b and RSM932A, induce cell death in cancer cells (T47D, MCF7, MDA-MB231, SW620 and H460), through the prolonged activation of ER stress response. Evidence of ChoKIs-induced ER stress includes enhanced production of glucose-regulated protein, 78 kDa (GRP78), protein disulfide isomerase, IRE1α, CHOP, CCAAT/enhancer-binding protein beta (C/EBPβ) and TRB3. Although partial reduction of ChoKα levels by small interfering RNA was not sufficient to increase the production of ER stress proteins, silencing of ChoKα levels also show a decrease in CHOP overproduction induced by ChoKIs, which suggests that ER stress induction is due to a change in ChoKα protein folding after binding to ChoKIs. Silencing of CHOP expression leads to a reduction in C/EBPβ, ATF3 and GRP78 protein levels and abrogates apoptosis in tumor cells after treatment with ChoKIs, suggesting that CHOP maintains ER stress responses and triggers the pro-apoptotic signal. Consistent with the differential effect of ChoKIs in cancer and primary cells previously described, ChoKIs only promoted a transient and moderated ER stress response in the non-tumorogenic cells MCF10A. In conclusion, pharmacological inhibition of ChoKα induces cancer cell death through a mechanism that involves the activation of exaggerated and persistent ER stress supported by CHOP overproduction. PMID:24287694

Mechanical stress and network structure drive protein dynamics during cytokinesis.

PubMed

Srivastava, Vasudha; Robinson, Douglas N

2015-03-02

Cell-shape changes associated with processes like cytokinesis and motility proceed on several-second timescales but are derived from molecular events, including protein-protein interactions, filament assembly, and force generation by molecular motors, all of which occur much faster [1-4]. Therefore, defining the dynamics of such molecular machinery is critical for understanding cell-shape regulation. In addition to signaling pathways, mechanical stresses also direct cytoskeletal protein accumulation [5-7]. A myosin-II-based mechanosensory system controls cellular contractility and shape during cytokinesis and under applied stress [6, 8]. In Dictyostelium, this system tunes myosin II accumulation by feedback through the actin network, particularly through the crosslinker cortexillin I. Cortexillin-binding IQGAPs are major regulators of this system. Here, we defined the short timescale dynamics of key cytoskeletal proteins during cytokinesis and under mechanical stress, using fluorescence recovery after photobleaching and fluorescence correlation spectroscopy, to examine the dynamic interplay between these proteins. Equatorially enriched proteins including cortexillin I, IQGAP2, and myosin II recovered much more slowly than actin and polar crosslinkers. The mobility of equatorial proteins was greatly reduced at the furrow compared to the interphase cortex, suggesting their stabilization during cytokinesis. This mobility shift did not arise from a single biochemical event, but rather from a global inhibition of protein dynamics by mechanical-stress-associated changes in the cytoskeletal structure. Mechanical tuning of contractile protein dynamics provides robustness to the cytoskeletal framework responsible for regulating cell shape and contributes to cytokinesis fidelity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Anti-Apoptotic Protein Bcl-xL Expression in the Midbrain Raphe Region Is Sensitive to Stress and Glucocorticoids

PubMed Central

Kalinina, Tatyana S.; Bulygina, Veta V.; Lanshakov, Dmitry A.; Babluk, Ekaterina V.

2015-01-01

Anti-apoptotic proteins are suggested to be important for the normal health of neurons and synapses as well as for resilience to stress. In order to determine whether stressful events may influence the expression of anti-apoptotic protein Bcl-xL in the midbrain and specifically in the midbrain serotonergic (5-HT) neurons involved in neurobehavioral responses to adverse stimuli, adult male rats were subjected to short-term or chronic forced swim stress. A short-term stress rapidly increased the midbrain bcl-xl mRNA levels and significantly elevated Bcl-xL immunoreactivity in the midbrain 5-HT cells. Stress-induced increase in glucocorticoid secretion was implicated in the observed effect. The levels of bcl-xl mRNA were decreased after stress when glucocorticoid elevation was inhibited by metyrapone (MET, 150 mg/kg), and this decrease was attenuated by glucocorticoid replacement with dexamethasone (DEX; 0.2 mg/kg). Both short-term stress and acute DEX administration, in parallel with Bcl-xL, caused a significant increase in tph2 mRNA levels and slightly enhanced tryptophan hydroxylase immunoreactivity in the midbrain. The increasing effect on the bcl-xl expression was specific to the short-term stress. Forced swim repeated daily for 2 weeks led to a decrease in bcl-xl mRNA in the midbrain without any effects on the Bcl-xL protein expression in the 5-HT neurons. In chronically stressed animals, an increase in tph2 gene expression was not associated with any changes in tryptophan hydroxylase protein levels. Our findings are the first to demonstrate that both short-term stress and acute glucocorticoid exposures induce Bcl-xL protein expression in the midbrain 5-HT neurons concomitantly with the activation of the 5-HT synthesis pathway in these neurons. PMID:26624017

Heterologous expression of a plastid EF-Tu reduces protein thermal aggregation and enhances CO2 fixation in wheat (Triticum aestivum) following heat stress.

PubMed

Fu, Jianming; Momcilović, Ivana; Clemente, Thomas E; Nersesian, Natalya; Trick, Harold N; Ristic, Zoran

2008-10-01

Heat stress is a major constraint to wheat production and negatively impacts grain quality, causing tremendous economic losses, and may become a more troublesome factor due to global warming. At the cellular level, heat stress causes denaturation and aggregation of proteins and injury to membranes leading to alterations in metabolic fluxes. Protein aggregation is irreversible, and protection of proteins from thermal aggregation is a strategy a cell uses to tolerate heat stress. Here we report on the development of transgenic wheat (Triticum aestivum) events, expressing a maize gene coding for plastidal protein synthesis elongation factor (EF-Tu), which, compared to non-transgenic plants, display reduced thermal aggregation of leaf proteins, reduced heat injury to photosynthetic membranes (thylakoids), and enhanced rate of CO(2) fixation after exposure to heat stress. The results support the concept that EF-Tu ameliorates negative effects of heat stress by acting as a molecular chaperone. This is the first demonstration of the introduction of a plastidal EF-Tu in plants that leads to protection against heat injury and enhanced photosynthesis after heat stress. This is also the first demonstration that a gene other than HSP gene can be used for improvement of heat tolerance and that the improvement is possible in a species that has a complex genome, hexaploid wheat. The results strongly suggest that heat tolerance of wheat, and possibly other crop plants, can be improved by modulating expression of plastidal EF-Tu and/or by selection of genotypes with increased endogenous levels of this protein.

Predicting the "Freshman 15": Environmental and Psychological Predictors of Weight Gain in First-Year University Students

ERIC Educational Resources Information Center

Vella-Zarb, Rachel A.; Elgar, Frank J.

2010-01-01

Objectives: (1) To investigate weight gain in first-year university students; and (2) to examine whether environmental and psychological factors, specifically accommodation and stress, predict weight gain. Methods: Eighty-four first-year university students (77 per cent female) were weighed and completed the Perceived Stress Scale (Cohen, Kamarck…

Taming the Anxious Mind: An 8-Week Mindfulness Meditation Group at a University Counseling Center

ERIC Educational Resources Information Center

Murphy, Michael C.

2006-01-01

This article describes an eight-week mindfulness meditation-based group that took place at a university counseling center. The group is patterned after the Mindfulness-Based Stress Reduction (MBSR) program developed by Dr. Jon Kabat-Zinn at the Stress Reduction Clinic at the University of Massachusetts Medical Center. Group members are taught…

Level of Perceived Stress Among Lectures in Nigerian Universities

ERIC Educational Resources Information Center

Ofoegbu, Felicia; Nwadiani, Mon

2006-01-01

The purpose of the study was to provide empirical evidence on the level of stress among lecturers in Nigerian universities. On the whole eight universities were used for the study. A sample of 228 (123 male and 105 female) lecturers was selected according to the variables of age, sex, marital status, experience, domicile, areas of specialization,…

Teaching Styles and Occupational Stress among Chinese University Faculty Members

ERIC Educational Resources Information Center

Zhang, Li-fang

2007-01-01

The primary aim of this research is to investigate the predictive power of occupational stress for teaching style among university faculty members. A sample of 144 faculty members from a large university in the People's Republic of China rated themselves on three ability scales and responded to the Thinking Styles in Teaching Inventory and to four…

The Relationship between Academic Stress and Two Aspects of Father Involvement among University Student Fathers

ERIC Educational Resources Information Center

Masciadrelli, Brian P.; Milardo, Robert M.

2008-01-01

This study investigated the associations between academic stress experienced by university student fathers and the behavioral and cognitive involvement these fathers had with their children. Fifty-three fathers enrolled in university classes and residing with at least one child less than 12 years of age responded to questionnaire measures of…

Different Roles of GRP78 on Cell Proliferation and Apoptosis in Cartilage Development.

PubMed

Xiong, Zhangyuan; Jiang, Rong; Li, Xiangzhu; Liu, Yanna; Guo, Fengjin

2015-09-07

Eukaryotic cells possess several mechanisms to adapt to endoplasmic reticulum (ER) stress and thereby survive. ER stress activates a set of signaling pathways collectively termed as the unfolded protein response (UPR). We previously reported that Bone morphogenetic protein 2 (BMP2) mediates mild ER stress and activates UPR signal molecules in chondrogenesis. The mammalian UPR protects the cell against the stress of misfolded proteins in the endoplasmic reticulum. Failure to adapt to ER stress causes the UPR to trigger apoptosis. Glucose regulated protein 78 (GRP78), as an important molecular chaperone in UPR signaling pathways, is responsible for binding to misfolded or unfolded protein during ER stress. However the influence on GRP78 in BMP2-induced chondrocyte differentiation has not yet been elucidated and the molecular mechanism underlyng these processes remain unexplored. Herein we demonstrate that overexpression of GRP78 enhanced cell proliferation in chondrocyte development with G1 phase advance, S phase increasing and G2-M phase transition. Furthermore, overexpression of GRP78 inhibited ER stress-mediated apoptosis and then reduced apoptosis in chondrogenesis induced by BMP2, as assayed by cleaved caspase3, caspase12, C/EBP homologous protein (CHOP/DDIT3/GADD153), p-JNK (phosphorylated c-Jun N-terminal kinase) expression during the course of chondrocyte differentiation by Western blot. In addition, flow cytometry (FCM) assay, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) assay and immune-histochemistry analysis also proved this result in vitro and in vivo. It was demonstrated that GRP78 knockdown via siRNA activated the ER stress-specific caspase cascade in developing chondrocyte tissue. Collectively, these findings reveal a novel critical role of GRP78 in regulating ER stress-mediated apoptosis in cartilage development and the molecular mechanisms involved.

Complex and extensive post-transcriptional regulation revealed by integrative proteomic and transcriptomic analysis of metabolite stress response in Clostridium acetobutylicum.

PubMed

Venkataramanan, Keerthi P; Min, Lie; Hou, Shuyu; Jones, Shawn W; Ralston, Matthew T; Lee, Kelvin H; Papoutsakis, E Terry

2015-01-01

Clostridium acetobutylicum is a model organism for both clostridial biology and solvent production. The organism is exposed to its own toxic metabolites butyrate and butanol, which trigger an adaptive stress response. Integrative analysis of proteomic and RNAseq data may provide novel insights into post-transcriptional regulation. The identified iTRAQ-based quantitative stress proteome is made up of 616 proteins with a 15 % genome coverage. The differentially expressed proteome correlated poorly with the corresponding differential RNAseq transcriptome. Up to 31 % of the differentially expressed proteins under stress displayed patterns opposite to those of the transcriptome, thus suggesting significant post-transcriptional regulation. The differential proteome of the translation machinery suggests that cells employ a different subset of ribosomal proteins under stress. Several highly upregulated proteins but with low mRNA levels possessed mRNAs with long 5'UTRs and strong RBS scores, thus supporting the argument that regulatory elements on the long 5'UTRs control their translation. For example, the oxidative stress response rubrerythrin was upregulated only at the protein level up to 40-fold without significant mRNA changes. We also identified many leaderless transcripts, several displaying different transcriptional start sites, thus suggesting mRNA-trimming mechanisms under stress. Downregulation of Rho and partner proteins pointed to changes in transcriptional elongation and termination under stress. The integrative proteomic-transcriptomic analysis demonstrated complex expression patterns of a large fraction of the proteome. Such patterns could not have been detected with one or the other omic analyses. Our analysis proposes the involvement of specific molecular mechanisms of post-transcriptional regulation to explain the observed complex stress response.

Loss of Mitofusin 2 Promotes Endoplasmic Reticulum Stress*

PubMed Central

Ngoh, Gladys A.; Papanicolaou, Kyriakos N.; Walsh, Kenneth

2012-01-01

The outer mitochondrial membrane GTPase mitofusin 2 (Mfn2) is known to regulate endoplasmic reticulum (ER) shape in addition to its mitochondrial fusion effects. However, its role in ER stress is unknown. We report here that induction of ER stress with either thapsigargin or tunicamycin in mouse embryonic fibroblasts leads to up-regulation of Mfn2 mRNA and protein levels with no change in the expression of the mitochondrial shaping factors Mfn1, Opa1, Drp1, and Fis1. Genetic deletion of Mfn2 but not Mfn1 in mouse embryonic fibroblasts or cardiac myocytes in mice led to an increase in the expression of the ER chaperone proteins. Genetic ablation of Mfn2 in mouse embryonic fibroblasts amplified ER stress and exacerbated ER stress-induced apoptosis. Deletion of Mfn2 delayed translational recovery through prolonged eIF2α phosphorylation associated with decreased GADD34 and p58IPK expression and elevated C/EBP homologous protein induction at late time points. These changes in the unfolded protein response were coupled to increased cell death reflected by augmented caspase 3/7 activity, lactate dehydrogenase release from cells, and an increase in propidium iodide-positive nuclei in response to thapsigargin or tunicamycin treatment. In contrast, genetic deletion of Mfn1 did not affect ER stress-mediated increase in ER chaperone synthesis or eIF2α phosphorylation. Additionally, ER stress-induced C/EBP homologous protein, GADD34, and p58IPK induction and cell death were not affected by loss of Mfn1. We conclude that Mfn2 but not Mfn1 is an ER stress-inducible protein that is required for the proper temporal sequence of the ER stress response. PMID:22511781

Endoplasmic Reticulum (ER) Stress and Endocrine Disorders

PubMed Central

Ariyasu, Daisuke; Yoshida, Hiderou; Hasegawa, Yukihiro

2017-01-01

The endoplasmic reticulum (ER) is the organelle where secretory and membrane proteins are synthesized and folded. Unfolded proteins that are retained within the ER can cause ER stress. Eukaryotic cells have a defense system called the “unfolded protein response” (UPR), which protects cells from ER stress. Cells undergo apoptosis when ER stress exceeds the capacity of the UPR, which has been revealed to cause human diseases. Although neurodegenerative diseases are well-known ER stress-related diseases, it has been discovered that endocrine diseases are also related to ER stress. In this review, we focus on ER stress-related human endocrine disorders. In addition to diabetes mellitus, which is well characterized, several relatively rare genetic disorders such as familial neurohypophyseal diabetes insipidus (FNDI), Wolfram syndrome, and isolated growth hormone deficiency type II (IGHD2) are discussed in this article. PMID:28208663

Abiotic stress signaling and responses in plants

PubMed Central

Zhu, Jian-Kang

2016-01-01

Summary As sessile organisms, plants must cope with abiotic stress such as soil salinity, drought, and extreme temperatures. Core stress signaling pathways involve protein kinases related to the yeast SNF1 and mammalian AMPK, suggesting that stress signaling in plants evolved from energy sensing. Stress signaling regulates proteins critical for ion and water transport and for metabolic and gene-expression reprogramming to bring about ionic and water homeostasis and cellular stability under stress conditions. Understanding stress signaling and responses will increase our ability to improve stress resistance in crops to achieve agricultural sustainability and food security for a growing world population. PMID:27716505

The Promoter of AtUSP Is Co-regulated by Phytohormones and Abiotic Stresses in Arabidopsis thaliana.

PubMed

Bhuria, Monika; Goel, Parul; Kumar, Sanjay; Singh, Anil K

2016-01-01

Universal stress proteins (USPs) are known to be expressed in response to various abiotic stresses in a wide variety of organisms, such as bacteria, archaebacteria, protists, algae, fungi, plants, and animals. However, in plants, biological function of most of the USPs still remains obscure. In the present study, Arabidopsis USP gene ( AtUSP ) showed induction in response to abscisic acid (ABA) and various abiotic stresses viz . heat, dehydration, salt, osmotic, and cold stresses. Additionally, in silico analysis of AtUSP promoter identified several cis -elements responsive to phytohormones and abiotic stresses such as ABRE, ERE, DRE, and HSE, etc. To functionally validate the AtUSP promoter, the 1115 bp region of promoter was characterized under phytohormone and abiotic stress treatments. Deletion analysis of promoter was carried out by cloning the full length promoter (D0) and its three 5' deletion derivatives, D1 (964 bp), D2 (660 bp), and D3 (503 bp) upstream of the β-glucuronidase (GUS) reporter gene, which were then stably transformed in Arabidopsis plants. The AtUSP promoter (D0) showed minimal activity under non-stress conditions which was enhanced in response to phytohormone treatments (ABA and ACC) and abiotic stresses such as dehydration, heat, cold, salt, and osmotic stresses. The seedlings harboring D1 and D2 deletion fragments showed constitutive GUS expression even under control condition with increased activity almost under all the treatments. However, D3 seedlings exhibited complete loss of activity under control condition with induction under ACC treatment, dehydration, heat, oxidative, salt, and osmotic stresses. Thus, present study clearly showed that AtUSP promoter is highly inducible by phytohormones and multiple abiotic stresses and it can be exploited as stress inducible promoter to generate multi-stress tolerant crops with minimal effects on their other important traits.

Seawater inhalation induces acute lung injury via ROS generation and the endoplasmic reticulum stress pathway

PubMed Central

Li, Cong-Cong; Lu, Xi; Qian, Wei-Sheng; Li, Yu-Juan; Jin, Fa-Guang; Mu, De-Guang

2018-01-01

Seawater (SW) inhalation can induce acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In the present study, SW induced apoptosis of rat alveolar epithelial cells and histopathological alterations to lung tissue. Furthermore, SW administration increased generation of reactive oxygen species (ROS), whereas pretreatment with the ROS scavenger, N-acetyl-L-cysteine (NAC), significantly decreased ROS generation, apoptosis and histopathological alterations. In addition, SW exposure upregulated the expression levels of glucose-regulated protein 78 (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP), which are critical proteins in the endoplasmic reticulum (ER) stress response, thus indicating that SW may activate ER stress. Conversely, blocking ER stress with 4-phenylbutyric acid (4-PBA) significantly improved SW-induced apoptosis and histopathological alterations, whereas an ER stress inducer, thapsigargin, had the opposite effect. Furthermore, blocking ROS with NAC inhibited SW-induced ER stress, as evidenced by the downregulation of GRP78, phosphorylated (p)-protein kinase R-like ER kinase (PERK), p-inositol-requiring kinase 1α (IRE1α), p-50 activating transcription factor 6α and CHOP. In addition, blocking ER stress with 4-PBA decreased ROS generation. In conclusion, the present study indicated that ROS and ER stress pathways, which are involved in alveolar epithelial cell apoptosis, are important in the pathogenesis of SW-induced ALI. PMID:29436612

A Comparative Proteome Approach Reveals Metabolic Changes Associated with Flammulina velutipes Mycelia in Response to Cold and Light Stress.

PubMed

Liu, Jing-Yu; Chang, Ming-Chang; Meng, Jun-Long; Feng, Cui-Ping; Wang, Yu

2018-04-11

In some industrial processes, cold and light stresses are recognized as two important environmental triggers for the transformation of mycelia into fruit-bodies via intermediate primordia in Flammulina velutipes cultivation. To gain insights into the mechanism of regulation of F. velutipes mycelia in response to cold and light stress, proteins expressed abundantly and characteristically at particular stress states were investigated by using the isobaric tags for the relative and absolute quantitation labeling technique. Among the 1046 nonredundant proteins identified with a high degree of confidence, 264 proteins, which were detected as differentially expressed proteins, were associated with 176 specific KEGG pathways. In-depth data analysis revealed that the regulatory network underlying the cold and light response mechanisms of F. velutipes mycelia was complex and multifaceted, as it included varied functions such as rapid energy supply, the biosynthesis of lysine, phenylalanine, tyrosine, and γ-aminobutyric acid, the calcium signal transduction process, dynein-dependent actin and microtubule cytoskeleton formation, autolysis, oxidative stress adaptation, pigment secretion, tissue and organ morphogenesis, and other interesting stress-related processes. Insights into the proteins might shed light on an intuitive understanding of the cold and light stress response mechanism underlying the fruiting processes of F. velutipes. Furthermore, the data might also provide further insights into the stress response mechanism of macro-fungi and valuable information for scientific improvement of some mushroom cultivation techniques in practice.

Interventions to reduce stress in university students: a review and meta-analysis.

PubMed

Regehr, Cheryl; Glancy, Dylan; Pitts, Annabel

2013-05-15

Recent research has revealed concerning rates of anxiety and depression among university students. Nevertheless, only a small percentage of these students receive treatment from university health services. Universities are thus challenged with instituting preventative programs that address student stress and reduce resultant anxiety and depression. A systematic review of the literature and meta-analysis was conducted to examine the effectiveness of interventions aimed at reducing stress in university students. Studies were eligible for inclusion if the assignment of study participants to experimental or control groups was by random allocation or parallel cohort design. Retrieved studies represented a variety of intervention approaches with students in a broad range of programs and disciplines. Twenty-four studies, involving 1431 students were included in the meta-analysis. Cognitive, behavioral and mindfulness interventions were associated with decreased symptoms of anxiety. Secondary outcomes included lower levels of depression and cortisol. Included studies were limited to those published in peer reviewed journals. These studies over-represent interventions with female students in Western countries. Studies on some types of interventions such as psycho-educational and arts based interventions did not have sufficient data for inclusion in the meta-analysis. This review provides evidence that cognitive, behavioral, and mindfulness interventions are effective in reducing stress in university students. Universities are encouraged to make such programs widely available to students. In addition however, future work should focus on developing stress reduction programs that attract male students and address their needs. Copyright © 2012 Elsevier B.V. All rights reserved.

Thermal Shock Induces Host Proteostasis Disruption and Endoplasmic Reticulum Stress in the Model Symbiotic Cnidarian Aiptasia.

PubMed

Oakley, Clinton A; Durand, Elysanne; Wilkinson, Shaun P; Peng, Lifeng; Weis, Virginia M; Grossman, Arthur R; Davy, Simon K

2017-06-02

Coral bleaching has devastating effects on coral survival and reef ecosystem function, but many of the fundamental cellular effects of thermal stress on cnidarian physiology are unclear. We used label-free liquid chromatography-tandem mass spectrometry to compare the effects of rapidly (33.5 °C, 24 h) and gradually (30 and 33.5 °C, 12 days) elevated temperatures on the proteome of the model symbiotic anemone Aiptasia. We identified 2133 proteins in Aiptasia, 136 of which were differentially abundant between treatments. Thermal shock, but not acclimation, resulted in significant abundance changes in 104 proteins, including those involved in protein folding and synthesis, redox homeostasis, and central metabolism. Nineteen abundant structural proteins showed particularly reduced abundance, demonstrating proteostasis disruption and potential protein synthesis inhibition. Heat shock induced antioxidant mechanisms and proteins involved in stabilizing nascent proteins, preventing protein aggregation and degrading damaged proteins, which is indicative of endoplasmic reticulum stress. Host proteostasis disruption occurred before either bleaching or symbiont photoinhibition was detected, suggesting host-derived reactive oxygen species production as the proximate cause of thermal damage. The pronounced abundance changes in endoplasmic reticulum proteins associated with proteostasis and protein turnover indicate that these processes are essential in the cellular response of symbiotic cnidarians to severe thermal stress.

Heat shock protein 70 as a biomarker of heat stress in a simulated hot cockpit.

PubMed

Kumar, Yadunanda; Chawla, Anuj; Tatu, Utpal

2003-07-01

Fighter pilots are frequently exposed to high temperatures during high-speed low-level flight. Heat strain can result in temporary impairment of cognitive functions and when severe, loss of consciousness and consequent loss of life and equipment. Induction of stress proteins is a highly conserved stress response mechanism from bacteria to humans. Induced stress protein levels are known to be cytoprotective and have been correlated with stress tolerance. Although many studies on the heat shock response mechanisms have been performed in cell culture and animal model systems, there is very limited information on stress protein induction in human subjects. Heat shock proteins (Hsp), especially Hsp70, may be induced in human subjects exposed to high temperatures in a hot cockpit designed to simulate heat stress experienced in low flying sorties. Six healthy volunteers were subjected to heat stress at 55 degrees C in a high temperature cockpit simulator for a period of 1 h at 30% humidity. Physiological parameters such as oral and skin temperatures, heart rate, and sweat rate were monitored regularly during this time. The level of Hsp70 in leukocytes was examined before and after the heat exposure in each subject. Hsp70 was found to be significantly induced in all the six subjects exposed to heat stress. The level of induced Hsp70 appears to correlate with other strain indicators such as accumulative circulatory strain and Craig's modified index. The usefulness of Hsp70 as a molecular marker of heat stress in humans is discussed.

Vemurafenib potently induces endoplasmic reticulum stress-mediated apoptosis in BRAFV600E melanoma cells

PubMed Central

Beck, Daniela; Niessner, Heike; Smalley, Keiran S.M.; Flaherty, Keith; Paraiso, Kim H.T.; Busch, Christian; Sinnberg, Tobias; Vasseur, Sophie; Iovanna, Juan Lucio; Drießen, Stefan; Stork, Björn; Wesselborg, Sebastian; Schaller, Martin; Biedermann, Tilo; Bauer, Jürgen; Lasithiotakis, Konstantinos; Weide, Benjamin; Eberle, Jürgen; Schittek, Birgit; Schadendorf, Dirk; Garbe, Claus; Kulms, Dagmar; Meier, Friedegund

2013-01-01

The V600E mutation in the kinase BRAF is frequently detected in melanomas and results in constitutive activation of BRAF, which then promotes cell proliferation by the mitogen-activated protein kinase (MAPK) signaling pathway. Although the BRAFV600E kinase inhibitor vemurafenib has remarkable antitumor activity in patients with BRAFV600E-mutated melanoma, its effects are limited by the onset of drug resistance. We found that exposure of melanoma cell lines with the BRAFV600E mutation to vemurafenib decreased the abundance of anti-apoptotic proteins and induced intrinsic mitochondrial apoptosis. Vemurafenib-treated melanoma cells showed increased cytosolic concentration of calcium, a potential trigger for endoplasmic reticulum (ER) stress, which can lead to apoptosis. Consistent with an ER stress-induced response, vemurafenib decreased the abundance of the ER chaperone protein GRP78, increased the abundance of the spliced isoform of the transcription factor X-box protein 1 (XBP1) (which transcriptionally activates genes involved in ER stress responses), increased the phosphorylation of the translation initiation factor eIF2α (which would be expected to inhibit protein synthesis), and induced the expression of ER stress-related genes. Knockdown of the ER stress response protein ATF4 significantly reduced vemurafenib-induced apoptosis. Moreover, the ER stress inducer thapsigargin prevented invasive growth of tumors formed from vemurafenib-sensitive melanoma cells in vivo. In melanoma cells with low sensitivity or resistance to vemurafenib, combination treatment with thapsigargin augmented or induced apoptosis. Thus, thapsigargin or other inducers of ER stress may be useful in combination therapies to overcome vemurafenib resistance. PMID:23362240

Comparative Analyses of Cu-Zn Superoxide Dismutase (SOD1) and Thioredoxin Reductase (TrxR) at the mRNA Level between Apis mellifera L. and Apis cerana F. (Hymenoptera: Apidae) Under Stress Conditions.

PubMed

Koo, Hyun-Na; Lee, Soon-Gyu; Yun, Seung-Hwan; Kim, Hyun Kyung; Choi, Yong Soo; Kim, Gil-Hah

2016-01-01

This study compared stress-induced expression of Cu-Zn superoxide dismutase (SOD1) and thioredoxin reductase (TrxR) genes in the European honeybee Apis mellifera L. and Asian honeybee Apis cerana F. Expression of both SOD1 and TrxR rapidly increased up to 5 h after exposure to cold (4 °C) or heat (37 °C) treatment and then gradually decreased, with a stronger effect induced by cold stress in A. mellifera compared with A. cerana. Injection of stress-inducing substances (methyl viologen, [MV] and H2O2) also increased SOD1 and TrxR expression in both A. mellifera and A. cerana, and this effect was more pronounced with MV than H2O2. Additionally, we heterologously expressed the A. mellifera and A. cerana SOD1 and TrxR proteins in an Escherichia coli expression system, and detection by SDS-PAGE, confirmed by Western blotting using anti-His tag antibodies, revealed bands at 16 and 60 kDa, respectively. Our results show that the expression patterns of SOD1 and TrxR differ between A. mellifera and A. cerana under conditions of low or high temperature as well as oxidative stress. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.

Elucidation of Cross-Talk and Specificity of Early Response Mechanisms to Salt and PEG-Simulated Drought Stresses in Brassica napus Using Comparative Proteomic Analysis

PubMed Central

Luo, Junling; Tang, Shaohua; Peng, Xiaojue; Yan, Xiaohong; Zeng, Xinhua; Li, Jun; Li, Xiaofei; Wu, Gang

2015-01-01

To understand the cross-talk and specificity of the early responses of plants to salt and drought, we performed physiological and proteome analyses of Brassica napus seedlings pretreated with 245 mM NaCl or 25% polyethylene glycol (PEG) 6000 under identical osmotic pressure (-1.0 MPa). Significant decreases in water content and photosynthetic rate and excessive accumulation of compatible osmolytes and oxidative damage were observed in response to both stresses. Unexpectedly, the drought response was more severe than the salt response. We further identified 45 common differentially expressed proteins (DEPs), 143 salt-specific DEPs and 160 drought-specific DEPs by isobaric tags for relative and absolute quantitation (iTRAQ) analysis. The proteome quantitative data were then confirmed by multiple reaction monitoring (MRM). The differences in the proteomic profiles between drought-treated and salt-treated seedlings exceeded the similarities in the early stress responses. Signal perception and transduction, transport and membrane trafficking, and photosynthesis-related proteins were enriched as part of the molecular cross-talk and specificity mechanism in the early responses to the two abiotic stresses. The Ca2+ signaling, G protein-related signaling, 14-3-3 signaling pathway and phosphorylation cascades were the common signal transduction pathways shared by both salt and drought stress responses; however, the proteins with executive functions varied. These results indicate functional specialization of family proteins in response to different stresses, i.e., CDPK21, TPR, and CTR1 specific to phosphorylation cascades under early salt stress, whereas STN7 and BSL were specific to phosphorylation cascades under early drought stress. Only the calcium-binding EF-hand family protein and ZKT were clearly identified as signaling proteins that acted as cross-talk nodes for salt and drought signaling pathways. Our study provides new clues and insights for developing strategies to improve the tolerance of crops to complex, multiple environmental stresses. PMID:26448643

Proteomic analysis of the flooding tolerance mechanism in mutant soybean.

PubMed

Komatsu, Setsuko; Nanjo, Yohei; Nishimura, Minoru

2013-02-21

Flooding stress of soybean is a serious problem because it reduces growth; however, flooding-tolerant cultivars have not been identified. To analyze the flooding tolerance mechanism of soybean, the flooding-tolerant mutant was isolated and analyzed using a proteomic technique. Flooding-tolerance tests were repeated five times using gamma-ray irradiated soybeans, whose root growth (M6 stage) was not suppressed even under flooding stress. Two-day-old wild-type and mutant plants were subjected to flooding stress for 2days, and proteins were identified using a gel-based proteomic technique. In wild-type under flooding stress, levels of proteins related to development, protein synthesis/degradation, secondary metabolism, and the cell wall changed; however, these proteins did not markedly differ in the mutant. In contrast, an increased number of fermentation-related proteins were identified in the mutant under flooding stress. The root tips of mutant plants were not affected by flooding stress, even though the wild-type plants had damaged root. Alcohol dehydrogenase activity in the mutant increased at an early stage of flooding stress compared with that of the wild-type. Taken together, these results suggest that activation of the fermentation system in the early stages of flooding may be an important factor for the acquisition of flooding tolerance in soybean. Copyright © 2012 Elsevier B.V. All rights reserved.

Td4IN2: A drought-responsive durum wheat (Triticum durum Desf.) gene coding for a resistance like protein with serine/threonine protein kinase, nucleotide binding site and leucine rich domains.

PubMed

Rampino, Patrizia; De Pascali, Mariarosaria; De Caroli, Monica; Luvisi, Andrea; De Bellis, Luigi; Piro, Gabriella; Perrotta, Carla

2017-11-01

Wheat, the main food source for a third of world population, appears strongly under threat because of predicted increasing temperatures coupled to drought. Plant complex molecular response to drought stress relies on the gene network controlling cell reactions to abiotic stress. In the natural environment, plants are subjected to the combination of abiotic and biotic stresses. Also the response of plants to biotic stress, to cope with pathogens, involves the activation of a molecular network. Investigations on combination of abiotic and biotic stresses indicate the existence of cross-talk between the two networks and a kind of overlapping can be hypothesized. In this work we describe the isolation and characterization of a drought-related durum wheat (Triticum durum Desf.) gene, identified in a previous study, coding for a protein combining features of NBS-LRR type resistance protein with a S/TPK domain, involved in drought stress response. This is one of the few examples reported where all three domains are present in a single protein and, to our knowledge, it is the first report on a gene specifically induced by drought stress and drought-related conditions, with this particular structure. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Involvement of Reactive Oxygen Species and Mitochondrial Proteins in Biophoton Emission in Roots of Soybean Plants under Flooding Stress.

PubMed

Kamal, Abu Hena Mostafa; Komatsu, Setsuko

2015-05-01

To understand the mechanism of biophoton emission, ROS and mitochondrial proteins were analyzed in soybean plants under flooding stress. Enzyme activity and biophoton emission were increased in the flooding stress samples when assayed in reaction mixes specific for antioxidant enzymes and reactive oxygen species; although the level of the hydroxyl radicals was increased at day 4 (2 days of flooding) compared to nonflooding at day 4, the emission of biophotons did not change. Mitochondria were isolated and purified from the roots of soybean plants grown under flooding stress by using a Percoll gradient, and proteins were analyzed by a gel-free proteomic technique. Out of the 98 mitochondrial proteins that significantly changed abundance under flooding stress, 47 increased and 51 decreased at day 4. The mitochondrial enzymes fumarase, glutathione-S-transferase, and aldehyde dehydrogenase increased at day 4 in protein abundance and enzyme activity. Enzyme activity and biophoton emission decreased at day 4 by the assay of lipoxygenase under stress. Aconitase, acyl CoA oxidase, succinate dehydrogenase, and NADH ubiquinone dehydrogenase were up-regulated at the transcription level. These results indicate that oxidation and peroxide scavenging might lead to biophoton emission and oxidative damage in the roots of soybean plants under flooding stress.

Hyperosmotic stress stimulates autophagy via polycystin-2.

PubMed

Peña-Oyarzun, Daniel; Troncoso, Rodrigo; Kretschmar, Catalina; Hernando, Cecilia; Budini, Mauricio; Morselli, Eugenia; Lavandero, Sergio; Criollo, Alfredo

2017-08-22

Various intracellular mechanisms are activated in response to stress, leading to adaptation or death. Autophagy, an intracellular process that promotes lysosomal degradation of proteins, is an adaptive response to several types of stress. Osmotic stress occurs under both physiological and pathological conditions, provoking mechanical stress and activating various osmoadaptive mechanisms. Polycystin-2 (PC2), a membrane protein of the polycystin family, is a mechanical sensor capable of activating the cell signaling pathways required for cell adaptation and survival. Here we show that hyperosmotic stress provoked by treatment with hyperosmolar concentrations of sorbitol or mannitol induces autophagy in HeLa and HCT116 cell lines. In addition, we show that mTOR and AMPK, two stress sensor proteins involved modulating autophagy, are downregulated and upregulated, respectively, when cells are subjected to hyperosmotic stress. Finally, our findings show that PC2 is required to promote hyperosmotic stress-induced autophagy. Downregulation of PC2 prevents inhibition of hyperosmotic stress-induced mTOR pathway activation. In conclusion, our data provide new insight into the role of PC2 as a mechanosensor that modulates autophagy under hyperosmotic stress conditions.

Hyperosmotic stress stimulates autophagy via polycystin-2

PubMed Central

Kretschmar, Catalina; Hernando, Cecilia; Budini, Mauricio; Morselli, Eugenia; Lavandero, Sergio; Criollo, Alfredo

2017-01-01

Various intracellular mechanisms are activated in response to stress, leading to adaptation or death. Autophagy, an intracellular process that promotes lysosomal degradation of proteins, is an adaptive response to several types of stress. Osmotic stress occurs under both physiological and pathological conditions, provoking mechanical stress and activating various osmoadaptive mechanisms. Polycystin-2 (PC2), a membrane protein of the polycystin family, is a mechanical sensor capable of activating the cell signaling pathways required for cell adaptation and survival. Here we show that hyperosmotic stress provoked by treatment with hyperosmolar concentrations of sorbitol or mannitol induces autophagy in HeLa and HCT116 cell lines. In addition, we show that mTOR and AMPK, two stress sensor proteins involved modulating autophagy, are downregulated and upregulated, respectively, when cells are subjected to hyperosmotic stress. Finally, our findings show that PC2 is required to promote hyperosmotic stress-induced autophagy. Downregulation of PC2 prevents inhibition of hyperosmotic stress-induced mTOR pathway activation. In conclusion, our data provide new insight into the role of PC2 as a mechanosensor that modulates autophagy under hyperosmotic stress conditions. PMID:28915568

Electrophilic aldehyde products of lipid peroxidation selectively adduct to heat shock protein 90 and arylsulfatase A in stallion spermatozoa.

PubMed

Hall, Sally E; Aitken, R John; Nixon, Brett; Smith, Nathan D; Gibb, Zamira

2017-01-01

Oxidative stress is a major determinant of mammalian sperm function stimulating lipid peroxidation cascades that culminate in the generation of potentially cytotoxic aldehydes. The aim of this study was to assess the impact of such aldehydes on the functionality of stallion spermatozoa. The impact of exposure to exogenous acrolein (ACR) and 4-hydroxynonenal (4HNE) was manifested in a highly significant dose- and time-dependent increase in mitochondrial reactive oxygen species (ROS), total cellular ROS, a decrease in sperm motility, and a time-dependent increase in lipid peroxidation. Notably, low doses of ACR and 4HNE also caused a significant decrease in zona binding. In contrast, exogenous malondialdehyde, a commonly used marker of oxidative stress, had little impact on the various sperm parameters assessed. In accounting for the negative physiological impact of ACR and 4HNE, it was noted that both aldehydes readily adducted to sperm proteins located predominantly within the head, proximal centriole, and tail. The detoxifying activity of mitochondrial aldehyde dehydrogenase 2 appeared responsible for a lack of adduction in the midpiece; however, this activity was overwhelmed by 24 h of electrophilic aldehyde exposure. Sequencing of the dominant proteins targeted for ACR and 4HNE covalent modification identified heat shock protein 90 alpha (cytosolic) class A member 1 and arylsulfatase A, respectively. These collective findings may prove useful in the identification of diagnostic biomarkers of stallion fertility and resolving the mechanistic basis of sperm dysfunction in this species. © The Authors 2016. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please journals.permissions@oup.com.

Overexpressed cyclophilin B suppresses apoptosis associated with ROS and Ca2+ homeostasis after ER stress.

PubMed

Kim, Jinhwan; Choi, Tae Gyu; Ding, Yan; Kim, Yeonghwan; Ha, Kwon Soo; Lee, Kyung Ho; Kang, Insug; Ha, Joohun; Kaufman, Randal J; Lee, Jinhwa; Choe, Wonchae; Kim, Sung Soo

2008-11-01

Prolonged accumulation of misfolded proteins in the endoplasmic reticulum (ER) results in ER stress-mediated apoptosis. Cyclophilins are protein chaperones that accelerate the rate of protein folding through their peptidyl-prolyl cis-trans isomerase (PPIase) activity. In this study, we demonstrated that ER stress activates the expression of the ER-localized cyclophilin B (CypB) gene through a novel ER stress response element. Overexpression of wild-type CypB attenuated ER stress-induced cell death, whereas overexpression of an isomerase activity-defective mutant, CypB/R62A, not only increased Ca(2+) leakage from the ER and ROS generation, but also decreased mitochondrial membrane potential, resulting in cell death following exposure to ER stress-inducing agents. siRNA-mediated inhibition of CypB expression rendered cells more vulnerable to ER stress. Finally, CypB interacted with the ER stress-related chaperones, Bip and Grp94. Taken together, we concluded that CypB performs a crucial function in protecting cells against ER stress via its PPIase activity.

Jasmonates: Multifunctional Roles in Stress Tolerance

PubMed Central

Ahmad, Parvaiz; Rasool, Saiema; Gul, Alvina; Sheikh, Subzar A.; Akram, Nudrat A.; Ashraf, Muhammad; Kazi, A. M.; Gucel, Salih

2016-01-01

Jasmonates (JAs) [Jasmonic acid (JA) and methyl jasmonates (MeJAs)] are known to take part in various physiological processes. Exogenous application of JAs so far tested on different plants under abiotic stresses particularly salinity, drought, and temperature (low/high) conditions have proved effective in improving plant stress tolerance. However, its extent of effectiveness entirely depends on the type of plant species tested or its concentration. The effects of introgression or silencing of different JA- and Me-JA-related genes have been summarized in this review, which have shown a substantial role in improving crop yield and quality in different plants under stress or non-stress conditions. Regulation of JAs synthesis is impaired in stressed as well as unstressed plant cells/tissues, which is believed to be associated with a variety of metabolic events including signal transduction. Although, mitogen activated protein kinases (MAPKs) are important components of JA signaling and biosynthesis pathways, nitric oxide, ROS, calcium, ABA, ethylene, and salicylic acid are also important mediators of plant growth and development during JA signal transduction and synthesis. The exploration of other signaling molecules can be beneficial to examine the details of underlying molecular mechanisms of JA signal transduction. Much work is to be done in near future to find the proper answers of the questions like action of JA related metabolites, and identification of universal JA receptors etc. Complete signaling pathways involving MAPKs, CDPK, TGA, SIPK, WIPK, and WRKY transcription factors are yet to be investigated to understand the complete mechanism of action of JAs. PMID:27379115

Degradation of the stress-responsive enzyme formate dehydrogenase by the RING-type E3 ligase Keep on Going and the ubiquitin 26S proteasome system.

PubMed

McNeilly, Daryl; Schofield, Andrew; Stone, Sophia L

2018-02-01

KEG is involved in mediating the proteasome-dependent degradation of FDH, a stress-responsive enzyme. The UPS may function to suppress FDH mediated stress responses under favorable growth conditions. Formate dehydrogenase (FDH) has been studied in bacteria and yeasts for the purpose of industrial application of NADH co-factor regeneration. In plants, FDH is regarded as a universal stress protein involved in responses to various abiotic and biotic stresses. Here we show that FDH abundance is regulated by the ubiquitin proteasome system (UPS). FDH is ubiquitinated in planta and degraded by the 26S proteasome. Interaction assays identified FDH as a potential substrate for the RING-type ubiquitin ligase Keep on Going (KEG). KEG is capable of attaching ubiquitin to FDH in in vitro assays and the turnover of FDH was increased when co-expressed with a functional KEG in planta, suggesting that KEG contributes to FDH degradation. Consistent with a role in regulating FDH abundance, transgenic plants overexpressing KEG were more sensitive to the inhibitory effects of formate. In addition, FDH is a phosphoprotein and dephosphorylation was found to increase the stability of FDH in degradation assays. Based on results from this and previous studies, we propose a model where KEG mediates the ubiquitination and subsequent degradation of phosphorylated FDH and, in response to unfavourable growth conditions, reduction in FDH phosphorylation levels may prohibit turnover allowing the stabilized FDH to facilitate stress responses.

Specific cross-reactivity of antibodies raised against two major stress proteins, stress 70 and chaperonin 60, in diverse species

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanders, B.M.; Martin, L.S.; Nakagawa, P.A.

1994-08-01

Immunoblot analysis using several antibodies raised against two major families of stress proteins, stress 70 and chaperonin 60 (cpn60), which are highly conserved in mammals, was carried out in diverse species often used in environmental research, including molluscs, annelids, crustaceans, echinoderms, and fish. The study revealed surprisingly different patterns of antibody cross-reactivity among species. The monoclonal anti-stress 70 antibody (mAb) C92 was the least cross-reactive for all species tested. The mAbs anti-stress 70 N27, BRM-22, and 3a3 were more broadly cross-reactive, but their binding specifities to stress 70 isoforms in the diverse species tested did not correlate with one anothermore » or follow taxonomic lines. The polyclonal anti-stress 70 antibody reacted to proteins in the 70 to 74 kDa range in all fish examined and in most invertebrates. When a polyclonal antibody (pAb) raised against cpn60 from a moth was used as a probe, specific binding was observed with proteins in the 60 to 64 kDa range in all fish examined and in most invertebrates. However, the size and number of isoforms that reacted with the pAb were species specific. These data suggest that these two major stress protein families are less highly conserved in invertebrates and fish than in mammals. Therefore, to minimize misinterpretation when using antibodies in heterologous assays with species in which the stress response has not been well characterized, it is important to determine which isoforms of stress 70 react with a particular antibody and to take into account the differential regulation of each member of this multigene family.« less

Stress and cardiometabolic manifestations among Saudi students entering universities: a cross-sectional observational study

PubMed Central

2014-01-01

Background In this observational study, we aimed to see whether transition in Saudi students entering university life could be a breeding stage for cardiometabolic risk factor emergence and clustering. Methods A total of 1878 apparently healthy Saudi students of the Preparatory Year, King Saud University, Riyadh, KSA (1112 men and 766 women) spanning 2 academic years were included. They were divided into 2 groups based on the validated perceived stress test (PST). Anthropometrics were obtained and fasting blood samples were collected for measurement of fasting blood glucose and a lipid profile. Results PST score (>27) considered indicative of stress was noted in 44.4% of students. The prevalence of this score was higher in women than in men (49.7% versus 40.7%). The prevalence of obesity, hypertension and dyslipidemia was significantly higher in men than women (p < 0.01), and this was even more apparent among stressed men, who had a significantly higher prevalence of all the above cardiometabolic factors than the non-stressed ones (p < 0.01). Conclusion Perceived stress is alarmingly high among Saudi students entering universities. This study sheds light on the social responsibility of universities in promoting a healthy lifestyle, particularly in this age group, when exposure to different kinds of stressors may result in body weight and metabolic changes. PMID:24755010

A Study on the Measurement of Job-Related Stress among Women Academics in Research Universities of China

ERIC Educational Resources Information Center

Zhang, Lili

2010-01-01

This study intends to gain an understanding of the sources of stress among women academics in research universities of China. Studies have shown that, compared with their male counterparts, women report higher level of stress in work/family conflicts, gender barriers and career development. Based on the results of this study, the following…

Analysis of protein oxidation in serum of fetal and newborn piglets and the influence of iron dextran on induction of protein carbonyls.

USDA-ARS?s Scientific Manuscript database

Methods were employed to evaluate serum biomarkers associated with protein oxidative stress and damage, to determine potential sources of metabolic stress in baby pigs. Protein carbonyls in serum were converted to dinitrophenyl (DNP) derivatives with DNP-hydrazine, precipitated with TCA, extracted i...

Membrane glycerolipid equilibrium under endoplasmic reticulum stress in Arabidopsis thaliana.

PubMed

Yu, Chao-Yuan; Nguyen, Van Cam; Chuang, Ling; Kanehara, Kazue

2018-06-02

Endoplasmic reticulum (ER) is an indispensable organelle for secretory protein synthesis as well as metabolism of phospholipids and their derivatives in eukaryotic cells. Various external and internal factors may cause an accumulation of aberrant proteins in the ER, which causes ER stress and activates cellular ER stress responses to cope with the stress. In animal research, molecular mechanisms for protein quality control upon ER stress are well documented; however, how cells maintain lipid homeostasis under ER stress is an emerging issue. The ratio of phosphatidylcholine (PC) to phosphatidylethanolamine (PE), two major phospholipid classes, is important under ER stress in animal cells. However, in seed plants, no study has reported on the changes in membrane lipid content under ER stress, although a number of physiologically important environmental stresses, such as heat and salinity, induce ER stress. Here, we investigated membrane glycerolipid metabolism under ER stress in Arabidopsis. ER stress transcriptionally affected PC and PE biosynthesis pathways differentially, with no significant changes in membrane glycerolipid content. Our results suggest that higher plants maintain membrane lipid equilibrium during active transcription of phospholipid biosynthetic genes under ER stress. Copyright © 2018 Elsevier Inc. All rights reserved.

Two-dimensional blue native/SDS-PAGE analysis of whole cell lysate protein complexes of rice in response to salt stress.

PubMed

Hashemi, Amenehsadat; Gharechahi, Javad; Nematzadeh, Ghorbanali; Shekari, Faezeh; Hosseini, Seyed Abdollah; Salekdeh, Ghasem Hosseini

2016-08-01

To understand the biology of a plant in response to stress, insight into protein-protein interactions, which almost define cell behavior, is thought to be crucial. Here, we provide a comparative complexomics analysis of leaf whole cell lysate of two rice genotypes with contrasting responses to salt using two-dimensional blue native/SDS-PAGE (2D-BN/SDS-PAGE). We aimed to identify changes in subunit composition and stoichiometry of protein complexes elicited by salt. Using mild detergent for protein complex solubilization, we were able to identify 9 protein assemblies as hetero-oligomeric and 30 as homo-oligomeric complexes. A total of 20 proteins were identified as monomers in the 2D-BN/SDS-PAGE gels. In addition to identifying known protein complexes that confirm the technical validity of our analysis, we were also able to discover novel protein-protein interactions. Interestingly, an interaction was detected for glycolytic enzymes enolase (ENO1) and triosephosphate isomerase (TPI) and also for a chlorophyll a-b binding protein and RuBisCo small subunit. To show changes in subunit composition and stoichiometry of protein assemblies during salt stress, the differential abundance of interacting proteins was compared between salt-treated and control plants. A detailed exploration of some of the protein complexes provided novel insight into the function, composition, stoichiometry and dynamics of known and previously uncharacterized protein complexes in response to salt stress. Copyright © 2016 Elsevier GmbH. All rights reserved.

Vitamin C mitigates oxidative/nitrosative stress and inflammation in doxorubicin-induced cardiomyopathy.

PubMed

Akolkar, Gauri; da Silva Dias, Danielle; Ayyappan, Prathapan; Bagchi, Ashim K; Jassal, Davinder S; Salemi, Vera Maria Cury; Irigoyen, Maria Claudia; De Angelis, Katia; Singal, Pawan K

2017-10-01

Increase in oxidative/nitrosative stress is one of the mechanisms associated with the development of cardiotoxicity due to doxorubicin (Dox), a potent chemotherapy drug. Previously, we reported mitigation of Dox-induced oxidative/nitrosative stress and apoptosis by vitamin C (Vit C) in isolated cardiomyocytes. In the present in vivo study in rats, we investigated the effect of prophylactic treatment with Vit C on Dox-induced apoptosis, inflammation, oxidative/nitrosative stress, cardiac dysfunction, and Vit C transporter proteins. Dox (cumulative dose: 15 mg/kg) in rats reduced systolic and diastolic cardiac function and caused structural damage. These changes were associated with a myocardial increase in reactive oxygen species, reduction in antioxidant enzyme activities, increased expression of apoptotic proteins, and inflammation. Dox also caused an increase in the expression of proapoptotic proteins Bax, Bnip-3, Bak, and caspase-3. An increase in oxidative/nitrosative stress attributable to Dox was indicated by an increase in superoxide, protein carbonyl formation, lipid peroxidation, nitric oxide (NO), NO synthase (NOS) activity, protein nitrosylation, and inducible NOS protein expression. Dox increased the levels of cardiac proinflammatory cytokines TNF-α, IL-1β, and IL-6, whereas the expression of Vit C transporter proteins (sodium-ascorbate cotransporter 2 and glucose transporter 4) was reduced. Prophylactic and concurrent treatment with Vit C prevented all these changes and improved survival in the Vit C + Dox group. Vit C also improved Dox-mediated systolic and diastolic dysfunctions and structural damage. These results suggest a cardioprotective role of Vit C in Dox-induced cardiomyopathy by reducing oxidative/nitrosative stress, inflammation, and apoptosis, as well as improving Vit C transporter proteins. NEW & NOTEWORTHY This in vivo study provides novel data that vitamin C improves cardiac structure and function in doxorubicin-induced cardiomyopathy by reducing oxidative/nitrosative stress, apoptosis, and inflammation along with upregulation of cardiac vitamin C transporter proteins. The latter may have a crucial role in improving antioxidant status in this cardiomyopathy. Copyright © 2017 the American Physiological Society.

Calcium affecting protein expression in longan under simulated acid rain stress.

PubMed

Pan, Tengfei; Li, Yongyu; Ma, Cuilan; Qiu, Dongliang

2015-08-01

Longan (Dimocarpus longana Lour. cv. Wulongling) of uniform one-aged seedlings grown in pots were selected to study specific proteins expressed in leaves under simulated acid rain (SiAR) stress and exogenous Ca(2+) regulation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results showed that there was a protein band specifically expressed under SiAR of pH 2.5 stress for 15 days with its molecular weight of about 23 kD. A 17 kD protein band specifically expressed after SiAR stress 5 days. Compared with pH 2.5, the pH 3.5 of SiAR made a less influence to protein expression. Two-dimensional electrophoresis (2-DE) results showed that six new specific proteins including C4 (20.2 kD pI 6.0), F (24 kD pI 6.35), B3 (22.3 kD pI 6.35), B4 (23.5 kD pI 6.5), C5 (21.8 kD pI 5.6), and C6 (20.2 kD pI 5.6) specifically expressed. C4 always expressed during SiAR stress. F expressed under the stress of pH 2.5 for 15 days and expressed in all pH SiAR stress for 20 days. The expression of proteins including B3, C5, and C6 was related to pH value and stress intensity of SiAR. The expression of B4 resulted from synergistic effects of SiAR and Ca. The expression of G1 (Mr 19.3 kD, pI 4.5), G2 (Mr 17.8 kD, pI 4.65), G3 (Mr 16.6 kD, pI 4.6), and G4 (Mr 14.7 kD, pI 4.4) enhanced under the treatment of 5 mM ethylene glycol tetraacetic acid (EGTA) and 2 mM chlorpromazine (CPZ). These proteins showed antagonistic effects and might be relative to the Ca-calmodulin (Ca-CaM) system of longan in response to SiAR stress.

The involvement of protein kinase C-ε in isoflurane induced preconditioning of human embryonic stem cell--derived Nkx2.5(+) cardiac progenitor cells.

PubMed

Song, In-Ae; Oh, Ah-Young; Kim, Jin-Hee; Choi, Young-Min; Jeon, Young-Tae; Ryu, Jung-Hee; Hwang, Jung-Won

2016-02-20

Anesthetic preconditioning can improve survival of cardiac progenitor cells exposed to oxidative stress. We investigated the role of protein kinase C and isoform protein kinase C-ε in isoflurane-induced preconditioning of cardiac progenitor cells exposed to oxidative stress. Cardiac progenitor cells were obtained from undifferentiated human embryonic stem cells. Immunostaining with anti-Nkx2.5 was used to confirm the differentiated cardiac progenitor cells. Oxidative stress was induced by H2O2 and FeSO4. For anesthetic preconditioning, cardiac progenitor cells were exposed to 0.25, 0.5, and 1.0 mM of isoflurane. PMA and chelerythrine were used for protein kinase C activation and inhibition, while εψRACK and εV1-2 were used for protein kinase C -ε activation and inhibition, respectively. Isoflurane-preconditioning decreased the death rate of Cardiac progenitor cells exposed to oxidative stress (death rates isoflurane 0.5 mM 12.7 ± 9.3%, 1.0 mM 12.0 ± 7.7% vs. control 31.4 ± 10.2%). Inhibitors of both protein kinase C and protein kinase C -ε abolished the preconditioning effect of isoflurane 0.5 mM (death rates 27.6 ± 13.5% and 25.9 ± 8.7% respectively), and activators of both protein kinase C and protein kinase C - ε had protective effects from oxidative stress (death rates 16.0 ± 3.2% and 10.6 ± 3.8% respectively). Both PKC and PKC-ε are involved in isoflurane-induced preconditioning of human embryonic stem cells -derived Nkx2.5(+) Cardiac progenitor cells under oxidative stress.

HSP70: therapeutic potential in acute and chronic cardiac disease settings.

PubMed

Bernardo, Bianca C; Weeks, Kate L; Patterson, Natalie L; McMullen, Julie R

2016-12-01

Heat shock proteins are a family of proteins that are produced by cells in response to exposure to stressful conditions. The best studied heat shock protein is HSP70, which is known to act as a molecular chaperone to maintain cellular homeostasis and inhibit protein aggregation in response to stress. While early animal studies suggested that increasing HSP70 in the heart (using a transgenic, gene transfer or pharmacological approach) provided cardiac protection against acute cardiac stress, recent studies have found no benefit of increasing HSP70 in mouse models of chronic cardiac stress. As HSP70 has been considered a potential therapeutic target, it is important to comprehensively assess HSP70 therapies in preclinical models of acute and chronic cardiac disease.

Stress tolerances of nullmutants of function-unknown genes encoding menadione stress-responsive proteins in Aspergillus nidulans.

PubMed

Leiter, Éva; Bálint, Mihály; Miskei, Márton; Orosz, Erzsébet; Szabó, Zsuzsa; Pócsi, István

2016-07-01

A group of menadione stress-responsive function-unkown genes of Aspergillus nidulans (Locus IDs ANID_03987.1, ANID_06058.1, ANID_10219.1, and ANID_10260.1) was deleted and phenotypically characterized. Importantly, comparative and phylogenetic analyses of the tested A. nidulans genes and their orthologs shed light only on the presence of a TANGO2 domain with NRDE protein motif in the translated ANID_06058.1 gene but did not reveal any recognizable protein-encoding domains in other protein sequences. The gene deletion strains were subjected to oxidative, osmotic, and metal ion stress and, surprisingly, only the ΔANID_10219.1 mutant showed an increased sensitivity to 0.12 mmol l(-1) menadione sodium bisulfite. The gene deletions affected the stress sensitivities (tolerances) irregularly, for example, some strains grew more slowly when exposed to various oxidants and/or osmotic stress generating agents, meanwhile the ΔANID_10260.1 mutant possessed a wild-type tolerance to all stressors tested. Our results are in line with earlier studies demonstrating that the deletions of stress-responsive genes do not confer necessarily any stress-sensitivity phenotypes, which can be attributed to compensatory mechanisms based on other elements of the stress response system with overlapping functions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Differential Expression and Immunolocalization of Antioxidant Enzymes in Entamoeba histolytica Isolates during Metronidazole Stress

PubMed Central

Iyer, Lakshmi Rani; Singh, Nishant; Verma, Anil Kumar; Paul, Jaishree

2014-01-01

Entamoeba histolytica infections are endemic in the Indian subcontinent. Five to eight percent of urban population residing under poor sanitary conditions suffers from Entamoeba infections. Metronidazole is the most widely prescribed drug used for amoebiasis. In order to understand the impact of metronidazole stress on the parasite, we evaluated the expression of two antioxidant enzymes, peroxiredoxin and FeSOD, in Entamoeba histolytica isolates during metronidazole stress. The results reveal that, under metronidazole stress, the mRNA expression levels of these enzymes did not undergo any significant change. Interestingly, immunolocalization studies with antibodies targeting peroxiredoxin indicate differential localization of the protein in the cell during metronidazole stress. In normal conditions, all the Entamoeba isolates exhibit presence of peroxiredoxin in the nucleus as well as in the membrane; however with metronidazole stress the protein localized mostly to the membrane. The change in the localization pattern was more pronounced when the cells were subjected to short term metronidazole stress compared to cells adapted to metronidazole. The protein localization to the cell membrane could be the stress response mechanism in these isolates. Colocalization pattern of peroxiredoxin with CaBp1, a cytosolic protein, revealed that the membrane and nuclear localization was specific to peroxiredoxin during metronidazole stress. PMID:25013795

Physiological and Proteomics Analyses Reveal the Mechanism of Eichhornia crassipes Tolerance to High-Concentration Cadmium Stress Compared with Pistia stratiotes

PubMed Central

Yang, Yunqiang; Yang, Shihai; Sun, Xudong; Yang, Yongping

2015-01-01

Cadmium (Cd) pollution is an environmental problem worldwide. Phytoremediation is a convenient method of removing Cd from both soil and water, but its efficiency is still low, especially in aquatic environments. Scientists have been trying to improve the ability of plants to absorb and accumulate Cd based on interactions between plants and Cd, especially the mechanism by which plants resist Cd. Eichhornia crassipes and Pistia stratiotes are aquatic plants commonly used in the phytoremediation of heavy metals. In the present study, we conducted physiological and biochemical analyses to compare the resistance of these two species to Cd stress at 100 mg/L. E. crassipes showed stronger resistance and was therefore used for subsequent comparative proteomics to explore the potential mechanism of E. crassipes tolerance to Cd stress at the protein level. The expression patterns of proteins in different functional categories revealed that the physiological activities and metabolic processes of E. crassipes were affected by exposure to Cd stress. However, when some proteins related to these processes were negatively inhibited, some analogous proteins were induced to compensate for the corresponding functions. As a result, E. crassipes could maintain more stable physiological parameters than P. stratiotes. Many stress-resistance substances and proteins, such as proline and heat shock proteins (HSPs) and post translational modifications, were found to be involved in the protection and repair of functional proteins. In addition, antioxidant enzymes played important roles in ROS detoxification. These findings will facilitate further understanding of the potential mechanism of plant response to Cd stress at the protein level. PMID:25886466

Proteins involved in biophoton emission and flooding-stress responses in soybean under light and dark conditions.

PubMed

Kamal, Abu Hena Mostafa; Komatsu, Setsuko

2016-02-01

To know the molecular systems basically flooding conditions in soybean, biophoton emission measurements and proteomic analyses were carried out for flooding-stressed roots under light and dark conditions. Photon emission was analyzed using a photon counter. Gel-free quantitative proteomics were performed to identify significant changes proteins using the nano LC-MS along with SIEVE software. Biophoton emissions were significantly increased in both light and dark conditions after flooding stress, but gradually decreased with continued flooding exposure compared to the control plants. Among the 120 significantly identified proteins in the roots of soybean plants, 73 and 19 proteins were decreased and increased in the light condition, respectively, and 4 and 24 proteins were increased and decreased, respectively, in the dark condition. The proteins were mainly functionally grouped into cell organization, protein degradation/synthesis, and glycolysis. The highly abundant lactate/malate dehydrogenase proteins were decreased in flooding-stressed roots exposed to light, whereas the lysine ketoglutarate reductase/saccharopine dehydrogenase bifunctional enzyme was increased in both light and dark conditions. Notably, however, specific enzyme assays revealed that the activities of these enzymes and biophoton emission were sharply increased after 3 days of flooding stress. This finding suggests that the source of biophoton emission in roots might involve the chemical excitation of electron or proton through enzymatic or non-enzymatic oxidation and reduction reactions. Moreover, the lysine ketoglutarate reductase/saccharopine dehydrogenase bifunctional enzyme may play important roles in responses in flooding stress of soybean under the light condition and as a contributing factor to biophoton emission.

An alternatively spliced heat shock transcription factor, OsHSFA2dI, functions in the heat stress-induced unfolded protein response in rice.

PubMed

Cheng, Q; Zhou, Y; Liu, Z; Zhang, L; Song, G; Guo, Z; Wang, W; Qu, X; Zhu, Y; Yang, D

2015-03-01

As sessile organisms, plants have evolved a wide range of defence pathways to cope with environmental stress such as heat shock. However, the molecular mechanism of these defence pathways remains unclear in rice. In this study, we found that OsHSFA2d, a heat shock transcriptional factor, encodes two main splice variant proteins, OsHSFA2dI and OsHSFA2dII in rice. Under normal conditions, OsHSFA2dII is the dominant but transcriptionally inactive spliced form. However, when the plant suffers heat stress, OsHSFA2d is alternatively spliced into a transcriptionally active form, OsHSFA2dI, which participates in the heat stress response (HSR). Further study found that this alternative splicing was induced by heat shock rather than photoperiod. We found that OsHSFA2dI is localised to the nucleus, whereas OsHSFA2dII is localised to the nucleus and cytoplasm. Moreover, expression of the unfolded protein response (UNFOLDED PROTEIN RESPONSE) sensors, OsIRE1, OsbZIP39/OsbZIP60 and the UNFOLDED PROTEIN RESPONSE marker OsBiP1, was up-regulated. Interestingly, OsbZIP50 was also alternatively spliced under heat stress, indicating that UNFOLDED PROTEIN RESPONSE signalling pathways were activated by heat stress to re-establish cellular protein homeostasis. We further demonstrated that OsHSFA2dI participated in the unfolded protein response by regulating expression of OsBiP1. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

Endoplasmic reticulum stress as a novel mechanism in amiodarone-induced destructive thyroiditis.

PubMed

Lombardi, Angela; Inabnet, William Barlow; Owen, Randall; Farenholtz, Kaitlyn Ellen; Tomer, Yaron

2015-01-01

Amiodarone (AMIO) is one of the most effective antiarrhythmic drugs available; however, its use is limited by a serious side effect profile, including thyroiditis. The mechanisms underlying AMIO thyroid toxicity have been elusive; thus, identification of novel approaches in order to prevent thyroiditis is essential in patients treated with AMIO. Our aim was to evaluate whether AMIO treatment could induce endoplasmic reticulum (ER) stress in human thyroid cells and the possible implications of this effect in AMIO-induced destructive thyroiditis. Here we report that AMIO, but not iodine, significantly induced the expression of ER stress markers including Ig heavy chain-binding protein (BiP), phosphoeukaryotic translation initiation factor 2α (eIF2α), CCAAT/enhancer-binding protein homologous protein (CHOP) and spliced X-box binding protein-1 (XBP-1) in human thyroid ML-1 cells and human primary thyrocytes. In both experimental systems AMIO down-regulated thyroglobulin (Tg) protein but had little effect on Tg mRNA levels, suggesting a mechanism involving Tg protein degradation. Indeed, pretreatment with the specific proteasome inhibitor MG132 reversed AMIO-induced down-regulation of Tg protein levels, confirming a proteasome-dependent degradation of Tg protein. Corroborating our findings, pretreatment of ML-1 cells and human primary thyrocytes with the chemical chaperone 4-phenylbutyric acid completely prevented the effect of AMIO on both ER stress induction and Tg down-regulation. We identified ER stress as a novel mechanism contributing to AMIO-induced destructive thyroiditis. Our data establish that AMIO-induced ER stress impairs Tg expression via proteasome activation, providing a valuable therapeutic avenue for the treatment of AMIO-induced destructive thyroiditis.

The endoplasmic reticulum in plant immunity and cell death

PubMed Central

Eichmann, Ruth; Schäfer, Patrick

2012-01-01

The endoplasmic reticulum (ER) is a highly dynamic organelle in eukaryotic cells and a major production site of proteins destined for vacuoles, the plasma membrane, or apoplast in plants. At the ER, these secreted proteins undergo multiple processing steps, which are supervised and conducted by the ER quality control system. Notably, processing of secreted proteins can considerably elevate under stress conditions and exceed ER folding capacities. The resulting accumulation of unfolded proteins is defined as ER stress. The efficiency of cells to re-establish proper ER function is crucial for stress adaptation. Besides delivering proteins directly antagonizing and resolving stress conditions, the ER monitors synthesis of immune receptors. This indicates the significance of the ER for the establishment and function of the plant immune system. Recent studies point out the fragility of the entire system and highlight the ER as initiator of programed cell death (PCD) in plants as was reported for vertebrates. This review summarizes current knowledge on the impact of the ER on immune and PCD signaling. Understanding the integration of stress signals by the ER bears a considerable potential to optimize development and to enhance stress resistance of plants. PMID:22936941

The endoplasmic reticulum in plant immunity and cell death.

PubMed

Eichmann, Ruth; Schäfer, Patrick

2012-01-01

The endoplasmic reticulum (ER) is a highly dynamic organelle in eukaryotic cells and a major production site of proteins destined for vacuoles, the plasma membrane, or apoplast in plants. At the ER, these secreted proteins undergo multiple processing steps, which are supervised and conducted by the ER quality control system. Notably, processing of secreted proteins can considerably elevate under stress conditions and exceed ER folding capacities. The resulting accumulation of unfolded proteins is defined as ER stress. The efficiency of cells to re-establish proper ER function is crucial for stress adaptation. Besides delivering proteins directly antagonizing and resolving stress conditions, the ER monitors synthesis of immune receptors. This indicates the significance of the ER for the establishment and function of the plant immune system. Recent studies point out the fragility of the entire system and highlight the ER as initiator of programed cell death (PCD) in plants as was reported for vertebrates. This review summarizes current knowledge on the impact of the ER on immune and PCD signaling. Understanding the integration of stress signals by the ER bears a considerable potential to optimize development and to enhance stress resistance of plants.

Lipid transfer protein 3 as a target of MYB96 mediates freezing and drought stress in Arabidopsis

PubMed Central

Yang, Shuhua

2013-01-01

Several lipid-transfer proteins were reported to modulate the plant response to biotic stress; however, whether lipid-transfer proteins are also involved in abiotic stress remains unknown. This study characterized the function of a lipid-transfer protein, LTP3, during freezing and drought stress. LTP3 was expressed ubiquitously and the LTP3 protein was localized to the cytoplasm. A biochemical study showed that LTP3 was able to bind to lipids. Overexpression of LTP3 resulted in constitutively enhanced freezing tolerance without affecting the expression of CBFs and their target COR genes. Further analyses showed that LTP3 was positively regulated by MYB96 via the direct binding to the LTP3 promoter; consistently, transgenic plants overexpressing MYB96 exhibited enhanced freezing tolerance. This study also found that the loss-of-function mutant ltp3 was sensitive to drought stress, whereas overexpressing plants were drought tolerant, phenotypes reminiscent of myb96 mutant plants and MYB96-overexpressing plants. Taken together, these results demonstrate that LTP3 acts as a target of MYB96 to be involved in plant tolerance to freezing and drought stress. PMID:23404903

Osmotic stress adaptation of Paracoccidioides lutzii, Pb01, monitored by proteomics.

PubMed

Rodrigues, Leandro Nascimento da Silva; Brito, Wesley de Almeida; Parente, Ana Flávia Alves; Weber, Simone Schneider; Bailão, Alexandre Melo; Casaletti, Luciana; Borges, Clayton Luiz; Soares, Célia Maria de Almeida

2016-10-01

The ability to respond to stressful conditions is essential for most living organisms. In pathogenic organisms, this response is required for effective transition from a saprophytic lifestyle to the establishment of pathogenic interactions within a susceptible host. Hyperosmotic stress has been used as a model to study signal transduction and seems to cause many cellular adaptations, including the alteration of protein expression and cellular volume as well as size regulation. In this work, we evaluated the proteomic profile of Paracoccidioides lutzii Pb01 yeast cells during osmotic stress induced by potassium chloride. We performed a high accuracy proteomic technique (NanoUPLC-MS(E)) to identify differentially expressed proteins during osmotic shock. The data describe an osmoadaptative response of this fungus when subjected to this treatment. Proteins involved in the synthesis of cell wall components were modulated, which suggested cell wall remodeling. In addition, alterations in the energy metabolism were observed. Furthermore, proteins involved in amino acid metabolism and hydrogen peroxide detoxification were modulated during osmotic stress. Our study suggests that P. lutzii Pb01. presents a vast osmoadaptative response that is composed of different proteins that act together to minimize the effects caused by osmotic stress. Copyright © 2016 Elsevier Inc. All rights reserved.

A Qualitative Study of HR/OHS Stress Interventions in Australian Universities.

PubMed

Pignata, Silvia; Winefield, Anthony H; Boyd, Carolyn M; Provis, Chris

2018-01-09

To enhance the understanding of psychosocial factors and extend research on work stress interventions, we investigated the key human resource (HR)/occupational health and safety (OHS) stress interventions implemented at five Australian universities over a three-year period. Five senior HR Directors completed an online survey to identify the intervention strategies taken at their university in order to reduce stress and enhance employee well-being and morale. We also explored the types of individual-, organization-, and individual/organization-directed interventions that were implemented, and the strategies that were prioritized at each university. Across universities, the dominant interventions were strategies that aimed to balance the social exchange in the work contract between employee-organization with an emphasis on initiatives to: enhance training, career development and promotional opportunities; improve remuneration and recognition practices; and to enhance the fairness of organizational policies and procedures. Strategies to improve work-life balance were also prominent. The interventions implemented were predominantly proactive (primary) strategies focused at the organizational level and aimed at eliminating or reducing or altering work stressors. The findings contribute to the improved management of people at work by identifying university-specific HR/OHS initiatives, specifically leadership development and management skills programs which were identified as priorities at three universities.

A Qualitative Study of HR/OHS Stress Interventions in Australian Universities

PubMed Central

Winefield, Anthony H.; Boyd, Carolyn M.

2018-01-01

To enhance the understanding of psychosocial factors and extend research on work stress interventions, we investigated the key human resource (HR)/occupational health and safety (OHS) stress interventions implemented at five Australian universities over a three-year period. Five senior HR Directors completed an online survey to identify the intervention strategies taken at their university in order to reduce stress and enhance employee well-being and morale. We also explored the types of individual-, organization-, and individual/organization-directed interventions that were implemented, and the strategies that were prioritized at each university. Across universities, the dominant interventions were strategies that aimed to balance the social exchange in the work contract between employee-organization with an emphasis on initiatives to: enhance training, career development and promotional opportunities; improve remuneration and recognition practices; and to enhance the fairness of organizational policies and procedures. Strategies to improve work-life balance were also prominent. The interventions implemented were predominantly proactive (primary) strategies focused at the organizational level and aimed at eliminating or reducing or altering work stressors. The findings contribute to the improved management of people at work by identifying university-specific HR/OHS initiatives, specifically leadership development and management skills programs which were identified as priorities at three universities. PMID:29315278

Tardigrade workbench: comparing stress-related proteins, sequence-similar and functional protein clusters as well as RNA elements in tardigrades

PubMed Central

2009-01-01

Background Tardigrades represent an animal phylum with extraordinary resistance to environmental stress. Results To gain insights into their stress-specific adaptation potential, major clusters of related and similar proteins are identified, as well as specific functional clusters delineated comparing all tardigrades and individual species (Milnesium tardigradum, Hypsibius dujardini, Echiniscus testudo, Tulinus stephaniae, Richtersius coronifer) and functional elements in tardigrade mRNAs are analysed. We find that 39.3% of the total sequences clustered in 58 clusters of more than 20 proteins. Among these are ten tardigrade specific as well as a number of stress-specific protein clusters. Tardigrade-specific functional adaptations include strong protein, DNA- and redox protection, maintenance and protein recycling. Specific regulatory elements regulate tardigrade mRNA stability such as lox P DICE elements whereas 14 other RNA elements of higher eukaryotes are not found. Further features of tardigrade specific adaption are rapidly identified by sequence and/or pattern search on the web-tool tardigrade analyzer http://waterbear.bioapps.biozentrum.uni-wuerzburg.de. The work-bench offers nucleotide pattern analysis for promotor and regulatory element detection (tardigrade specific; nrdb) as well as rapid COG search for function assignments including species-specific repositories of all analysed data. Conclusion Different protein clusters and regulatory elements implicated in tardigrade stress adaptations are analysed including unpublished tardigrade sequences. PMID:19821996

Tardigrade workbench: comparing stress-related proteins, sequence-similar and functional protein clusters as well as RNA elements in tardigrades.

PubMed

Förster, Frank; Liang, Chunguang; Shkumatov, Alexander; Beisser, Daniela; Engelmann, Julia C; Schnölzer, Martina; Frohme, Marcus; Müller, Tobias; Schill, Ralph O; Dandekar, Thomas

2009-10-12

Tardigrades represent an animal phylum with extraordinary resistance to environmental stress. To gain insights into their stress-specific adaptation potential, major clusters of related and similar proteins are identified, as well as specific functional clusters delineated comparing all tardigrades and individual species (Milnesium tardigradum, Hypsibius dujardini, Echiniscus testudo, Tulinus stephaniae, Richtersius coronifer) and functional elements in tardigrade mRNAs are analysed. We find that 39.3% of the total sequences clustered in 58 clusters of more than 20 proteins. Among these are ten tardigrade specific as well as a number of stress-specific protein clusters. Tardigrade-specific functional adaptations include strong protein, DNA- and redox protection, maintenance and protein recycling. Specific regulatory elements regulate tardigrade mRNA stability such as lox P DICE elements whereas 14 other RNA elements of higher eukaryotes are not found. Further features of tardigrade specific adaption are rapidly identified by sequence and/or pattern search on the web-tool tardigrade analyzer http://waterbear.bioapps.biozentrum.uni-wuerzburg.de. The work-bench offers nucleotide pattern analysis for promotor and regulatory element detection (tardigrade specific; nrdb) as well as rapid COG search for function assignments including species-specific repositories of all analysed data. Different protein clusters and regulatory elements implicated in tardigrade stress adaptations are analysed including unpublished tardigrade sequences.

Hub Protein Controversy: Taking a Closer Look at Plant Stress Response Hubs

PubMed Central

Vandereyken, Katy; Van Leene, Jelle; De Coninck, Barbara; Cammue, Bruno P. A.

2018-01-01

Plant stress responses involve numerous changes at the molecular and cellular level and are regulated by highly complex signaling pathways. Studying protein-protein interactions (PPIs) and the resulting networks is therefore becoming increasingly important in understanding these responses. Crucial in PPI networks are the so-called hubs or hub proteins, commonly defined as the most highly connected central proteins in scale-free PPI networks. However, despite their importance, a growing amount of confusion and controversy seems to exist regarding hub protein identification, characterization and classification. In order to highlight these inconsistencies and stimulate further clarification, this review critically analyses the current knowledge on hub proteins in the plant interactome field. We focus on current hub protein definitions, including the properties generally seen as hub-defining, and the challenges and approaches associated with hub protein identification. Furthermore, we give an overview of the most important large-scale plant PPI studies of the last decade that identified hub proteins, pointing out the lack of overlap between different studies. As such, it appears that although major advances are being made in the plant interactome field, defining hub proteins is still heavily dependent on the quality, origin and interpretation of the acquired PPI data. Nevertheless, many hub proteins seem to have a reported role in the plant stress response, including transcription factors, protein kinases and phosphatases, ubiquitin proteasome system related proteins, (co-)chaperones and redox signaling proteins. A significant number of identified plant stress hubs are however still functionally uncharacterized, making them interesting targets for future research. This review clearly shows the ongoing improvements in the plant interactome field but also calls attention to the need for a more comprehensive and precise identification of hub proteins, allowing a more efficient systems biology driven unraveling of complex processes, including those involved in stress responses. PMID:29922309

A Profile of an Endosymbiont-enriched Fraction of the Coral Stylophora pistillata Reveals Proteins Relevant to Microbial-Host Interactions*

PubMed Central

Weston, Andrew J.; Dunlap, Walter C.; Shick, J. Malcolm; Klueter, Anke; Iglic, Katrina; Vukelic, Ana; Starcevic, Antonio; Ward, Malcolm; Wells, Mark L.; Trick, Charles G.; Long, Paul F.

2012-01-01

This study examines the response of Symbiodinium sp. endosymbionts from the coral Stylophora pistillata to moderate levels of thermal “bleaching” stress, with and without trace metal limitation. Using quantitative high throughput proteomics, we identified 8098 MS/MS events relating to individual peptides from the endosymbiont-enriched fraction, including 109 peptides meeting stringent criteria for quantification, of which only 26 showed significant change in our experimental treatments; 12 of 26 increased expression in response to thermal stress with little difference affected by iron limitation. Surprisingly, there were no significant increases in antioxidant or heat stress proteins; those induced to higher expression were generally involved in protein biosynthesis. An outstanding exception was a massive 114-fold increase of a viral replication protein indicating that thermal stress may substantially increase viral load and thereby contribute to the etiology of coral bleaching and disease. In the absence of a sequenced genome for Symbiodinium or other photosymbiotic dinoflagellate, this proteome reveals a plethora of proteins potentially involved in microbial-host interactions. This includes photosystem proteins, DNA repair enzymes, antioxidant enzymes, metabolic redox enzymes, heat shock proteins, globin hemoproteins, proteins of nitrogen metabolism, and a wide range of viral proteins associated with these endosymbiont-enriched samples. Also present were 21 unusual peptide/protein toxins thought to originate from either microbial consorts or from contamination by coral nematocysts. Of particular interest are the proteins of apoptosis, vesicular transport, and endo/exocytosis, which are discussed in context of the cellular processes of coral bleaching. Notably, the protein complement provides evidence that, rather than being expelled by the host, stressed endosymbionts may mediate their own departure. PMID:22351649

Constitutive and Inducible Aerobic and Anaerobic Stress Proteins in the Echinochloa Complex and Rice.

PubMed Central

Mujer, C. V.; Rumpho, M. E.; Lin, J. J.; Kennedy, R. A.

1993-01-01

Anaerobic stress resulted in a change in the protein accumulation patterns in shoots of several Echinochloa (barnyard grass) species and Oryza sativa (L.) (rice) as resolved by two-dimensional gel electrophoresis. Of the six Echinochloa species investigated, E. phyllopogon (Stev.) Koss, E. muricata (Beauv.) Fern, E. oryzoides (Ard.) Fritsch Clayton, and E. crus-galli (L.) Beauv. are tolerant of anaerobiosis and germinate in the absence of oxygen, as does rice. In contrast, E. crus-pavonis (H.B.K.) Schult and E. colonum (L.) Link are intolerant and do not germinate without oxygen. Computer analysis of the protein patterns from the four tolerant species and rice indicated that the anaerobic response is of five classes: class 1 proteins, enhanced under anaerobiosis (9 to 13 polypeptides ranging from 16-68 kD); class 2 proteins, unique to anaerobiosis (1 to 5 polypeptides ranging from 17-69 kD); class 3 proteins, remained constant under aerobiosis and anaerobiosis; class 4 proteins, prominent only in air and repressed under anoxia (3 to 7 polypeptides ranging from 19-45 kD); and class 5 proteins, unique to aerobiosis (1 to 4 polypeptides ranging from 18-63 kD). In the intolerant species, E. colonum and E. crus-pavonis, no polypeptides were enhanced or repressed under anoxia (class 1 and class 4, respectively), whereas in the tolerant Echinochloa species and rice, a total of at least 9 to 13 anaerobic stress proteins and 4 to 7 "aerobic" proteins were noted. Immunoblotting identified two of the major anaerobic stress proteins as fructose-1,6-bisphosphate aldolase and pyruvate decarboxylase. Based on the differential response of the intolerant species to anaerobiosis, we suggest that another set of genes, whose products may not necessarily be among the major anaerobic stress polypeptides, might confer tolerance in Echinochloa under prolonged anaerobic stress. PMID:12231678

Extra Large G-Protein Interactome Reveals Multiple Stress Response Function and Partner-Dependent XLG Subcellular Localization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liang, Ying; Gao, Yajun; Jones, Alan M.

The three-member family of Arabidopsis extra-large G proteins (XLG1-3) defines the prototype of an atypical Ga subunit in the heterotrimeric G protein complex. Some recent evidence indicate that XLG subunits operate along with its Gbg dimer in root morphology, stress responsiveness, and cytokinin induced development, however downstream targets of activated XLG proteins in the stress pathways are rarely known. In order to assemble a set of candidate XLG-targeted proteins, a yeast two-hybrid complementation-based screen was performed using XLG protein baits to query interactions between XLG and partner protein found in glucose-treated seedlings, roots, and Arabidopsis cells in culture. Seventy twomore » interactors were identified and >60% of a test set displayed in vivo interaction with XLG proteins. Gene co-expression analysis shows that >70% of the interactors are positively correlated with the corresponding XLG partners. Gene Ontology enrichment for all the candidates indicates stress responses and posits a molecular mechanism involving a specific set of transcription factor partners to XLG. Genes encoding two of these transcription factors, SZF1 and 2, require XLG proteins for full NaCl-induced expression. Furthermore, the subcellular localization of the XLG proteins in the nucleus, endosome, and plasma membrane is dependent on the specific interacting partner.« less

Extra Large G-Protein Interactome Reveals Multiple Stress Response Function and Partner-Dependent XLG Subcellular Localization

DOE PAGES

Liang, Ying; Gao, Yajun; Jones, Alan M.

2017-06-13

The three-member family of Arabidopsis extra-large G proteins (XLG1-3) defines the prototype of an atypical Ga subunit in the heterotrimeric G protein complex. Some recent evidence indicate that XLG subunits operate along with its Gbg dimer in root morphology, stress responsiveness, and cytokinin induced development, however downstream targets of activated XLG proteins in the stress pathways are rarely known. In order to assemble a set of candidate XLG-targeted proteins, a yeast two-hybrid complementation-based screen was performed using XLG protein baits to query interactions between XLG and partner protein found in glucose-treated seedlings, roots, and Arabidopsis cells in culture. Seventy twomore » interactors were identified and >60% of a test set displayed in vivo interaction with XLG proteins. Gene co-expression analysis shows that >70% of the interactors are positively correlated with the corresponding XLG partners. Gene Ontology enrichment for all the candidates indicates stress responses and posits a molecular mechanism involving a specific set of transcription factor partners to XLG. Genes encoding two of these transcription factors, SZF1 and 2, require XLG proteins for full NaCl-induced expression. Furthermore, the subcellular localization of the XLG proteins in the nucleus, endosome, and plasma membrane is dependent on the specific interacting partner.« less

Isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analysis of Cryptococcus humicola response to aluminum stress.

PubMed

Zhang, Jingjing; Zhang, Lei; Qiu, Jinkui; Nian, Hongjuan

2015-10-01

Cryptococcus humicola is a highly aluminum (Al) tolerant yeast strain isolated from a tea field. Here the relative changes of protein expression in C. humicola undergoing aluminum stress were analyzed to understand the genetic basis of aluminum tolerance. In this work, iTRAQ-based (isobaric tags for relative and absolute quantification) quantitative proteomic technology was used to detect statistically significant proteins associated with the response to aluminum stress. A total of 625 proteins were identified and were mainly involved in translation/ribosomal structure and biogenesis, posttranslational modification/protein turnover/chaperones, energy production and conversion, and amino acid transport and metabolism. Of these proteins, 59 exhibited differential expression during aluminum stress. Twenty-nine proteins up-regulated by aluminum were mainly involved in translation/ribosomal structure and biogenesis, posttranslational modification/protein turnover and chaperones, and lipid transport and metabolism. Thirty proteins down-regulated by aluminum were mainly associated with energy transport and metabolism, translation/ribosomal structure and biogenesis, posttranslational modification/protein turnover/chaperones, and lipid transport and metabolism. The potential functions of some proteins in aluminum tolerance are discussed. These functional changes may be beneficial for cells to protect themselves from aluminum toxic conditions. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Effects of Biodanza on Stress, Depression, and Sleep Quality in University Students.

PubMed

López-Rodríguez, María Mar; Baldrich-Rodríguez, Ingrid; Ruiz-Muelle, Alicia; Cortés-Rodríguez, Alda Elena; Lopezosa-Estepa, Teresa; Roman, Pablo

2017-07-01

The existing literature shows dance to be an innovative and successful form of stress management. Previous research indicates that Biodanza is able to increase well-being and personal resources and prevent stress. However, Biodanza has not yet been empirically tested as a possible therapy for application outside the clinical context in young adults with perceived stress. This study aimed to determine the effectiveness of Biodanza in reducing symptoms of perceived stress and depression and in promoting sleep quality in young adults, comparing the changes with those observed in a control group. Randomized controlled trial. This study was carried out at the Faculty of Health Sciences of the University of Almería. One hundred and twenty-one university students with perceived stress were randomly placed into either a Biodanza group or a wait-list control group. Study participants attended Biodanza sessions for 90 min a week, over a period of 4 weeks. Depression, perceived stress, and sleep quality were assessed both before and after intervention. Ninety-five participants completed the program and were included in the statistical analysis. Significant differences in perceived stress [t (93) = 2.136; p = 0.015] and depression [t (93) = 2.738; p = 0.000] were observed after the Biodanza period. Pre/post analysis found that Biodanza also had a significant effect on depression (Cohen d = 1.88; p < 0.05) and perceived stress (Cohen d = 0.79; p < 0.05). The Biodanza program is an effective stress management strategy for students. The results of this study showed Biodanza to have a positive effect on perceived stress and depression in young adults. This demonstrates how artistic, collaborative, and psychophysical interventions are an effective means of preventing and managing these problems in university students.

Association of abdominal obesity, insulin resistance, and oxidative stress in adipose tissue in women with polycystic ovary syndrome.

PubMed

Chen, Li; Xu, Wen Ming; Zhang, Dan

2014-10-01

To study the expression of insulin signaling-related genes and oxidative stress markers in the visceral adipose tissue obtained from polycystic ovary syndrome (PCOS) patients and healthy control subjects and to investigate the relationships among abdominal obesity, insulin resistance, and oxidative stress at the tissue level. Case-control study. University teaching hospital. In total, 30 PCOS patients and 30 healthy control subjects, who underwent laparoscopic surgery, were included in the study. Abdominal obesity was defined based on waist circumference (WC). The homeostasis model index was used to assess insulin resistance (HOMA-IR). Gene expression of glucose transporter 4 (GLUT4) and insulin receptor substrate 1 (IRS1) in visceral adipose tissue (VAT) and the parameters of oxidative stress, such as superoxide dismutase, enzyme glutathione reductase, and dimethylarginine, were measured, and the expression of protein oxidative damage product 3-nitro-tyrosine residues (nitrotyrosine) in VAT was identified with the use of immunohistochemistry. PCOS was associated with lower expression of GLUT4 and IRS1 and a higher level of oxidative stress in VAT, which was strongly correlated with WC and HOMA-IR. Presence of abdominal obesity further intensified the correlations observed in our measurements. The nitrotyrosine expression in VAT was stronger in PCOS patients. The strong correlation of insulin resistance with oxidative stress at the VAT level suggests that local oxidative stress and abnormalities of insulin signaling in adipose tissue play critical roles in the pathogenesis of PCOS. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Arabidopsis Reduces Growth Under Osmotic Stress by Decreasing SPEECHLESS Protein

PubMed Central

Kumari, Archana; Jewaria, Pawan K.; Bergmann, Dominique C.; Kakimoto, Tatsuo

2014-01-01

Plants, which are sessile unlike most animals, have evolved a system to reduce growth under stress; however, the molecular mechanisms of this stress response are not well known. During programmed development, a fraction of the leaf epidermal precursor cells become meristemoid mother cells (MMCs), which are stem cells that produce both stomatal guard cells and epidermal pavement cells. Here we report that Arabidopsis plants, in response to osmotic stress, post-transcriptionally decrease the protein level of SPEECHLESS, the transcription factor promoting MMC identity, through the action of a mitogen-activated protein kinase (MAPK) cascade. The growth reduction under osmotic stress was lessened by inhibition of the MAPK cascade or by a mutation that disrupted the MAPK target amino acids in SPEECHLESS, indicating that Arabidopsis reduces growth under stress by integrating the osmotic stress signal into the MAPK–SPEECHLESS core developmental pathway. PMID:25381317

Induction of the cellular stress response in Chironomus (Diptera)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pardalis, G.; Hudson, L.A.; Ciborowski, J.J.H.

1995-12-31

The accumulation of stress or heat shock proteins is involved in the protection and defense of a cell from environmentally induced damage. Under stressful conditions, cytoplasmic stress protein 70 migrates to the nucleus where it assists in the restoration of the nucleolar function. The authors have demonstrated a dose-response relationship between incidence of decreased nucleolar size in chironomid salivary glands and degree of sediment contamination. Reduced nucleolar size is indicative of reduced nucleolar function. The relationship between nucleolus size and stress protein accumulation is being explored. They are conducting experiments on chironomids to characterize the response elicited by heat shockmore » and PAH exposure in the laboratory to determine if the simultaneous action of more than one stressor can significantly alter the stress response. Simultaneous studies are being conducted to validate these biomarkers in mesocosm caging experiments. Aspects of the response will be useful as biomarkers of general stress.« less

Proteomic profiling of γ-ECS overexpressed transgenic Nicotiana in response to drought stress.

PubMed

Kumar, Deepak; Datta, Riddhi; Sinha, Ragini; Ghosh, Aparupa; Chattopadhyay, Sharmila

2014-01-01

The contribution of Glutathione (GSH) in drought stress tolerance is an established fact. However, the proteins which are directly or indirectly related to the increased level of GSH in response to drought stress are yet to be known. To explore this, here, transgenic tobacco plants (NtGp11) overexpressing gamma-glutamylcysteine synthetase (γ-ECS) was tested for tolerance against drought stress. NtGp11 conferred tolerance to drought stress by increased germination rate, water retention, water recovery, chlorophyll, and proline content compared with wild-type plants. Semi-quantitative RT-PCR analysis revealed that the transcript levels of stress-responsive genes were higher in NtGp11 compared with wild-type in response to drought stress. Two-dimensional gel electrophoresis (2-DE) coupled with MALDI TOF-TOF MS/MS analysis has been used to identify 43 differentially expressed proteins in response to drought in wild-type and NtGp11 plants. The results demonstrated the up-accumulation of 58.1% of proteins among which 36%, 24%, and 20% of them were related to stress and defense, carbon metabolism and energy metabolism categories, respectively. Taken together, our results demonstrated that GSH plays an important role in combating drought stress in plants by inducing stress related genes and proteins like HSP70, chalcone synthase, glutathione peroxidase, thioredoxin peroxidase, ACC oxidase, and heme oxygenase I.

Proteomic profiling of γ-ECS overexpressed transgenic Nicotiana in response to drought stress.

PubMed

Kumar, Deepak; Datta, Riddhi; Sinha, Ragini; Ghosh, Aparupa; Chattopadhyay, Sharmila

2014-05-20

The contribution of Glutathione (GSH) in drought stress tolerance is an established fact. However, the proteins which are directly or indirectly related to the increased level of GSH in response to drought stress are yet to be known. To explore this, here, transgenic tobacco plants (NtGp 11) overexpressing gamma-glutamylcysteine synthetase (γ-ECS) was tested for tolerance against drought stress. NtGp 11 conferred tolerance to drought stress by increased germination rate, water retention, water recovery, chlorophyll, and proline content compared with wild-type plants. Semi-quantitative RT-PCR analysis revealed that the transcript levels of stress-responsive genes were higher in NtGp 11 compared with wild-type in response to drought stress. Two-dimensional gel electrophoresis (2-DE) coupled with MALDI TOF-TOF MS/MS analysis has been used to identify 43 differentially expressed proteins in response to drought in wild-type and NtGp 11 plants. The results demonstrated the up-accumulation of 58.1% of proteins among which 36%, 24%, and 20% of them were related to stress and defense, carbon metabolism and energy metabolism categories, respectively. Taken together, our results demonstrated that GSH plays an important role in combating drought stress in plants by inducing stress related genes and proteins like HSP70, chalcone synthase, glutathione peroxidase, thioredoxin peroxidase, ACC oxidase, and heme oxygenase I.

Organ-specific proteomics of soybean seedlings under flooding and drought stresses.

PubMed

Wang, Xin; Khodadadi, Ehsaneh; Fakheri, Baratali; Komatsu, Setsuko

2017-06-06

Organ-specific analyses enrich the understanding of plant growth and development under abiotic stresses. To elucidate the cellular responses in soybean seedlings exposed to flooding and drought stresses, organ-specific analysis was performed using a gel-free/label-free proteomic technique. Physiological analysis indicated that enzyme activities of alcohol dehydrogenase and delta-1-pyrroline-5-carboxylate synthase were markedly increased in leaf and root of plants treated with 6days of flooding and drought stresses, respectively. Proteins related to photosynthesis, RNA, DNA, signaling, and the tricarboxylic acid cycle were predominately affected in leaf, hypocotyl, and root in response to flooding and drought. Notably, the tricarboxylic acid cycle was suppressed in leaf and root under both stresses. Moreover, 17 proteins, including beta-glucosidase 31 and beta-amylase 5, were identified in soybean seedlings under both stresses. The protein abundances of beta-glucosidase 31 and beta-amylase 5 were increased in leaf and root under both stresses. Additionally, the gene expression of beta-amylase 5 was upregulated in leaf exposed to the flooding and drought, and the expression level was highly correlated with the protein abundance. These results suggest that beta-amylase 5 may be involved in carbohydrate mobilization to provide energy to the leaf of soybean seedlings exposed to flooding and drought. This study examined the effects of flooding and drought on soybean seedlings in different organs using a gel-free/label-free proteomic approach. Physiological responses indicated that enzyme activities of alcohol dehydrogenase and delta-1-pyrroline-5-carboxylate synthase were increased in leaf and root of soybean seedlings exposed to flooding and drought for 6days. Functional analysis of acquired protein profiles exhibited that proteins related to photosynthesis, RNA, DNA, signaling, and the tricarboxylic acid cycle were predominated affected in leaf, hypocotyl, and root under both stresses. Moreover, the tricarboxylic acid cycle was suppressed in leaf and root of stressed soybean seedlings. Additionally, increased protein abundance of beta-amylase 5 was consistent with upregulated gene expression in the leaf under both stresses, suggesting that carbohydrate metabolism might be governed in response to flooding and drought of soybean seedlings. Copyright © 2017 Elsevier B.V. All rights reserved.

RNA Recognition and Stress Granule Formation by TIA Proteins

PubMed Central

Waris, Saboora; Wilce, Matthew Charles James; Wilce, Jacqueline Anne

2014-01-01

Stress granule (SG) formation is a primary mechanism through which gene expression is rapidly modulated when the eukaryotic cell undergoes cellular stresses (including heat, oxidative, viral infection, starvation). In particular, the sequestration of specifically targeted translationally stalled mRNAs into SGs limits the expression of a subset of genes, but allows the expression of heatshock proteins that have a protective effect in the cell. The importance of SGs is seen in several disease states in which SG function is disrupted. Fundamental to SG formation are the T cell restricted intracellular antigen (TIA) proteins (TIA-1 and TIA-1 related protein (TIAR)), that both directly bind to target RNA and self-associate to seed the formation of SGs. Here a summary is provided of the current understanding of the way in which TIA proteins target specific mRNA, and how TIA self-association is triggered under conditions of cellular stress. PMID:25522169

Proteomic analysis of Trichoderma atroviride mycelia stressed by organophosphate pesticide dichlorvos.

PubMed

Tang, Jun; Liu, Lixing; Huang, Xiuli; Li, Yingying; Chen, Yunpeng; Chen, Jie

2010-02-01

The proteomic approach is a powerful tool to study microbial response to environmental stress. To evaluate the responses of Trichoderma spp. to the organophosphate pesticide dichlorvos, mycelia of Trichoderma atroviride T23 were exposed to dichlorvos at concentrations of 0, 100, 300, 500, and 1000 microg/mL, respectively. Changes in protein expression were investigated using two-dimensional sodium dodecyl sulfate - polyacrylamide gel electrophoresis. Sixteen protein spots were differentially expressed. They were identified by MALDI-TOF/TOF MS and were found to be linked to energy metabolism, transport, signal transduction, and stress tolerance. Among stress-related proteins, glutathione peroxidase-like protein (GPX), 1,4-benzoquinone reductase, and HEX1 were upregulated by and cyclophilin A induced by 1000 microg/mL dichlorvos when compared with the control. These proteins were considered to be associated with fungal adaptation to adverse conditions. The results will help us to understand molecular mechanisms through which Trichoderma responds to organophosphate pesticides.

The impact of respiration and oxidative stress response on recombinant α-amylase production by Saccharomyces cerevisiae.

PubMed

Martínez, José L; Meza, Eugenio; Petranovic, Dina; Nielsen, Jens

2016-12-01

Studying protein production is important for fundamental research on cell biology and applied research for biotechnology. Yeast Saccharomyces cerevisiae is an attractive workhorse for production of recombinant proteins as it does not secrete many endogenous proteins and it is therefore easy to purify a secreted product. However, recombinant production at high rates represents a significant metabolic burden for the yeast cells, which results in oxidative stress and ultimately affects the protein production capacity. Here we describe a method to reduce the overall oxidative stress by overexpressing the endogenous HAP1 gene in a S. cerevisiae strain overproducing recombinant α-amylase. We demonstrate how Hap1p can activate a set of oxidative stress response genes and meanwhile contribute to increase the metabolic rate of the yeast strains, therefore mitigating the negative effect of the ROS accumulation associated to protein folding and hence increasing the production capacity during batch fermentations.

Drinking behaviors by stress level in Korean university students.

PubMed

Chung, Hye-Kyung; Lee, Hae-Young

2012-04-01

The purposes of this study are to estimate the stress level of university students, and to verify the relationships between stress level and drinking behavior. A questionnaire survey was administered to 430 university students in the Gangwon area in Korea from November 5 to November 28, 2008, and data from 391 students were used for the final statistical analysis. The most stressful factor was "Worry about academic achievements" (2.86 by Likert-type 4 point scale). The subjects were divided into two groups, a low stress group (≤ 65.0) and a high stress group (≥ 66.0), by the mean value (65.1) and median value (66.0) of the stress levels. The drinking frequency was not different between the two stress groups, but the amount of alcohol consumption was significantly different (P < 0.05). The portion of students reporting drinking "7 glasses or over" was higher in the lower stress group than in the higher stress group. In addition, factor 6, "Lack of learning ability", was negatively correlated with drinking frequency and the amount of alcohol consumption (P < 0.05), and factor 3, "Worry about academic achievements", was negatively correlated with the amount of drinking (P < 0.05). The major motive for drinking was "When overjoyed or there is something to celebrate" (2.62), and the main expected effect of drinking was "Drinking enables me to get together with people and shape my sociability" (2.73). The higher stress group showed significantly higher scores on several items in the categories of motives (P < 0.01), negative experience (P < 0.05), and expected effects (P < 0.05) of drinking than the lower stress group. Our results imply that university students at the lower stress level may drink more from social motives in positive drinking environments, while those at the higher stress level may have more problematic-drinking despite their smaller amount of alcohol consumption.

A universal entropy-driven mechanism for thioredoxin–target recognition

PubMed Central

Palde, Prakash B.; Carroll, Kate S.

2015-01-01

Cysteine residues in cytosolic proteins are maintained in their reduced state, but can undergo oxidation owing to posttranslational modification during redox signaling or under conditions of oxidative stress. In large part, the reduction of oxidized protein cysteines is mediated by a small 12-kDa thiol oxidoreductase, thioredoxin (Trx). Trx provides reducing equivalents for central metabolic enzymes and is implicated in redox regulation of a wide number of target proteins, including transcription factors. Despite its importance in cellular redox homeostasis, the precise mechanism by which Trx recognizes target proteins, especially in the absence of any apparent signature binding sequence or motif, remains unknown. Knowledge of the forces associated with the molecular recognition that governs Trx–protein interactions is fundamental to our understanding of target specificity. To gain insight into Trx–target recognition, we have thermodynamically characterized the noncovalent interactions between Trx and target proteins before S-S reduction using isothermal titration calorimetry (ITC). Our findings indicate that Trx recognizes the oxidized form of its target proteins with exquisite selectivity, compared with their reduced counterparts. Furthermore, we show that recognition is dependent on the conformational restriction inherent to oxidized targets. Significantly, the thermodynamic signatures for multiple Trx targets reveal favorable entropic contributions as the major recognition force dictating these protein–protein interactions. Taken together, our data afford significant new insight into the molecular forces responsible for Trx–target recognition and should aid the design of new strategies for thiol oxidoreductase inhibition. PMID:26080424

Gel-free/label-free proteomic analysis of developing rice grains under heat stress.

PubMed

Timabud, Tarinee; Yin, Xiaojian; Pongdontri, Paweena; Komatsu, Setsuko

2016-02-05

High temperature markedly reduces the yields and quality of rice grains. To identify the mechanisms underlying heat stress-induced responses in rice grains, proteomic technique was used. Developing Khao Dawk Mali 105 rice grains at the milky, dough, and mature stages were treated at 40 °C for 3 days. Aromatic compounds were decreased in rice grains under heat stress. The protein abundance involved in glycolysis and tricarboxylic acid cycle, including glyceraldehyde 3-phosphate dehydrogenase and citrate synthase, was changed in milky and dough grains after heat treatment; however, none changes in mature grains. The abundance involved in amino acid metabolism was increased in dough grains, but decreased in milky grains. In addition, the abundance involved in starch and sucrose metabolism, such as starch synthase, ADP-glucose pyrophosphorylase, granule-bound starch synthase, and alpha amylase, was decreased in milky grains, but increased in dough grains. A number of redox homeostasis-related proteins, such as ascorbate peroxidase and peroxiredoxin, were increased in developing rice grains treated with heat stress. These results suggest that in response to heat stress, the abundance of numerous proteins involved in redox homeostasis and carbohydrate biosynthetic pathways may play a major role in the development of KDML105 rice grains. Yield of Khao Dawk Mali 105 rice, which is an economical aromatic rice, was disrupted by environmental stress. Rice grains developed under heat stress caused loss of aroma compound. To identify the mechanism of heat response in rice grain, gel-free/label-free proteomic technique was used. The abundance of proteins involved in glycolysis and tricarboxylic acid cycle was disrupted by heat stress. High temperature limited starch biosynthesis; however, it enhanced sugar biosynthesis in developing rice grains. Redox homeostasis related proteins were disrupted by heat stress. These results suggest that proteins involved in redox homeostasis and carbohydrate pathway might play a major role in developing grains in Khao Dawk Mali 105 rice under heat stress. Copyright © 2015 Elsevier B.V. All rights reserved.

Proteomic analysis of Camellia sinensis (L.) reveals a synergistic network in the response to drought stress and recovery.

PubMed

Wang, Yu; Fan, Kai; Wang, Jing; Ding, Zhao-Tang; Wang, Hui; Bi, Cai-Hong; Zhang, Yun-Wei; Sun, Hai-Wei

2017-12-01

Drought is a crucial limiting factor for tea yield and quality. To systematically characterize the molecular response of tea plants to drought stress and its capacity to recover, we used iTRAQ-based comparative proteomic approach to investigate the effects of drought on protein expression profiles in tea seedlings subjected to different drought treatments. A total of 3274 proteins were identified, of which 2169 and 2300 showed differential expressions during drought and recovery, respectively. Functional annotation showed that multiple biological processes were regulated, suggesting that tea plants probably employed multiple and synergistic resistance mechanisms in dealing with drought stress. Hierarchical clustering showed that chlorophyll a/b-binding proteins were up-regulated in DB and RE, suggesting that tea plants might regulate expression of chlorophyll a/b-binding proteins to maintain the photosystem II function during drought stress. Abundant proteins involved in sulfur-containing metabolite pathways, such as glutathione, taurine, hypotaurine, methionine, and cysteine, changed significantly during drought stress. Among them, TL29 interacted with LHCb6 to connect S-containing metabolites with chlorophyll a/b-binding proteins. This suggests that sulfur-containing compounds play important roles in the response to drought stress in tea plants. In addition, the expression of PAL was up-regulated in DA and down-regulated in DB. Cinnamyl alcohol dehydrogenase, caffeic acid O-methyltransferase, and 4-coumarate-CoA ligase also showed significant changes in expression levels, which regulated the biosynthesis of polyphenols. The results indicate that slight drought stress might promote polyphenol biosynthesis, while serious drought stress leads to inhibition. The expression of lipoxygenase and short-chain dehydrogenase increased during slight drought stress and some volatile metabolite pathways were enriched, indicating that drought stress might affect the tea aroma. The study provides valuable information that will lay the foundation for studies investigating the functions of drought response genes in tea leaves. Copyright © 2017 Elsevier GmbH. All rights reserved.

The effects of heat stress on morphological properties and intracellular signaling of denervated and intact soleus muscles in rats.

PubMed

Ohira, Takashi; Higashibata, Akira; Seki, Masaya; Kurata, Yoichi; Kimura, Yayoi; Hirano, Hisashi; Kusakari, Yoichiro; Minamisawa, Susumu; Kudo, Takashi; Takahashi, Satoru; Ohira, Yoshinobu; Furukawa, Satoshi

2017-08-01

The effects of heat stress on the morphological properties and intracellular signaling of innervated and denervated soleus muscles were investigated. Heat stress was applied to rats by immersing their hindlimbs in a warm water bath (42°C, 30 min/day, every other day following unilateral denervation) under anesthesia. During 14 days of experimental period, heat stress for a total of seven times promoted growth-related hypertrophy in sham-operated muscles and attenuated atrophy in denervated muscles. In denervated muscles, the transcription of ubiquitin ligase, atrogin-1/muscle atrophy F-box ( Atrogin-1 ), and muscle RING-finger protein-1 ( MuRF-1 ), genes was upregulated and ubiquitination of proteins was also increased. Intermittent heat stress inhibited the upregulation of Atrogin-1 , but not MuRF-1 transcription. And the denervation-caused reduction in phosphorylated protein kinase B (Akt), 70-kDa heat-shock protein (HSP70), and peroxisome proliferator-activated receptor γ coactivator-1 α (PGC-1 α ), which are negative regulators of Atrogin-1 and MuRF-1 transcription, was mitigated. In sham-operated muscles, repeated application of heat stress did not affect Atrogin-1 and MuRF-1 transcription, but increased the level of phosphorylated Akt and HSP70, but not PGC-1 α Furthermore, the phosphorylation of Akt and ribosomal protein S6, which is known to stimulate protein synthesis, was increased immediately after a single heat stress particularly in the sham-operated muscles. The effect of a heat stress was suppressed in denervated muscles. These results indicated that the beneficial effects of heat stress on the morphological properties of muscles were brought regardless of innervation. However, the responses of intracellular signaling to heat stress were distinct between the innervated and denervated muscles. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Advances and New Concepts in Alcohol-Induced Organelle Stress, Unfolded Protein Responses and Organ Damage.

PubMed

Ji, Cheng

2015-06-03

Alcohol is a simple and consumable biomolecule yet its excessive consumption disturbs numerous biological pathways damaging nearly all organs of the human body. One of the essential biological processes affected by the harmful effects of alcohol is proteostasis, which regulates the balance between biogenesis and turnover of proteins within and outside the cell. A significant amount of published evidence indicates that alcohol and its metabolites directly or indirectly interfere with protein homeostasis in the endoplasmic reticulum (ER) causing an accumulation of unfolded or misfolded proteins, which triggers the unfolded protein response (UPR) leading to either restoration of homeostasis or cell death, inflammation and other pathologies under severe and chronic alcohol conditions. The UPR senses the abnormal protein accumulation and activates transcription factors that regulate nuclear transcription of genes related to ER function. Similarly, this kind of protein stress response can occur in other cellular organelles, which is an evolving field of interest. Here, I review recent advances in the alcohol-induced ER stress response as well as discuss new concepts on alcohol-induced mitochondrial, Golgi and lysosomal stress responses and injuries.

ERdj5 sensitizes neuroblastoma cells to endoplasmic reticulum stress-induced apoptosis.

PubMed

Thomas, Christophoros G; Spyrou, Giannis

2009-03-06

Down-regulation of the unfolded protein response (UPR) can be therapeutically valuable in cancer treatment, and endoplasmic reticulum (ER)-resident chaperone proteins may thus be targets for developing novel chemotherapeutic strategies. ERdj5 is a novel ER chaperone that regulates the ER-associated degradation of misfolded proteins through its associations with EDEM and the ER stress sensor BiP. To investigate whether ERdj5 can regulate ER stress signaling pathways, we exposed neuroblastoma cells overexpressing ERdj5 to ER stress inducers. ERdj5 promoted apoptosis in tunicamycin, thapsigargin, and bortezomib-treated cells. To provide further evidence that ERdj5 induces ER stress-regulated apoptosis, we targeted Bcl-2 to ER of ERdj5-overexpressing cells. Targeting the Bcl-2 to ER prevented the apoptosis induced by ER stress inducers but not by non-ER stress apoptotic stimuli, suggesting induction of ER stress-regulated apoptosis by ERdj5. ERdj5 enhanced apoptosis by abolishing the ER stress-induced phosphorylation of eukaryotic translation initiation factor 2alpha (eIF2alpha) and the subsequent translational repression. ERdj5 was found to inhibit the eIF2alpha phosphorylation under ER stress through inactivating the pancreatic endoplasmic reticulum kinase. The compromised integrated stress response observed in ERdj5-overexpressing ER-stressed cells due to repressed eIF2alpha phosphorylation correlated with impaired neuroblastoma cell resistance under ER stress. These results demonstrate that ERdj5 decreases neuroblastoma cell survival by down-regulating the UPR, raising the possibility that this protein could be a target for anti-tumor approaches.

How Enzymes Work: A Look through the Perspective of Molecular Viscoelastic Properties

NASA Astrophysics Data System (ADS)

Qu, Hao; Zocchi, Giovanni

2013-01-01

We present nanorheology measurements on the folded state of an enzyme that show directly that the (ensemble-averaged) stress-strain relations are nonlinear and frequency dependent beyond 1-Å deformation. We argue that this frequency dependence allows for opening a nonequilibrium cycle in the force-deformation plane if the forward and backward conformational changes of the enzyme during catalysis happen at different speeds. Using a heuristic model for the experimentally established viscoelastic properties of the enzyme, we examine a number of general features of enzymatic action. We find that the proposed viscoelastic cycle is consistent with the linear decrease of the speed of motor proteins with load. We find a relation between the stall force and the maximum rate for enzymes (in general) and motors (in particular). We estimate the stall force of the motor protein kinesin from thermodynamic quantities and estimate the maximum rate of enzymes from purely mechanical quantities. We propose that the viscoelastic cycle provides a framework for considering mechanochemical coupling in enzymes on the basis of possibly universal materials properties of the folded state of proteins.

An integrated proteomic approach uncovers novel substrates and functions of the Lon protease in Escherichia coli.

PubMed

Arends, Jan; Griego, Marcena; Thomanek, Nikolas; Lindemann, Claudia; Kutscher, Blanka; Meyer, Helmut E; Narberhaus, Franz

2018-04-30

Controlling the cellular abundance and proper function of proteins by proteolysis is a universal process in all living organisms. In Escherichia coli, the ATP-dependent Lon protease is crucial for protein quality control and regulatory processes. To understand how diverse substrates are selected and degraded, unbiased global approaches are needed. We employed a quantitative Super-SILAC mass spectrometry approach and compared the proteomes of a lon mutant and a strain producing the protease to discover Lon-dependent physiological functions. To identify Lon substrates, we took advantage of a Lon trapping variant, which is able to translocate substrates but unable to degrade them. Lon-associated proteins were identified by label-free LC-MS/MS. The combination of both approaches revealed a total of 14 novel Lon substrates. Besides the identification of known pathways affected by Lon, for example the superoxide-stress response, our cumulative data suggests previously unrecognized fundamental functions of Lon in sulfur assimilation, nucleotide biosynthesis, amino acid and central energy metabolism. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Hepatitis C virus (HCV) induces formation of stress granules whose proteins regulate HCV RNA replication and virus assembly and egress.

PubMed

Garaigorta, Urtzi; Heim, Markus H; Boyd, Bryan; Wieland, Stefan; Chisari, Francis V

2012-10-01

Stress granules (SGs) are cytoplasmic structures that are induced in response to environmental stress, including viral infections. Here we report that hepatitis C virus (HCV) triggers the appearance of SGs in a PKR- and interferon (IFN)-dependent manner. Moreover, we show an inverse correlation between the presence of stress granules and the induction of IFN-stimulated proteins, i.e., MxA and USP18, in HCV-infected cells despite high-level expression of the corresponding MxA and USP18 mRNAs, suggesting that interferon-stimulated gene translation is inhibited in stress granule-containing HCV-infected cells. Finally, in short hairpin RNA (shRNA) knockdown experiments, we found that the stress granule proteins T-cell-restricted intracellular antigen 1 (TIA-1), TIA1-related protein (TIAR), and RasGAP-SH3 domain binding protein 1 (G3BP1) are required for efficient HCV RNA and protein accumulation at early time points in the infection and that G3BP1 and TIA-1 are required for intracellular and extracellular infectious virus production late in the infection, suggesting that they are required for virus assembly. In contrast, TIAR downregulation decreases extracellular infectious virus titers with little effect on intracellular RNA content or infectivity late in the infection, suggesting that it is required for infectious particle release. Collectively, these results illustrate that HCV exploits the stress granule machinery at least two ways: by inducing the formation of SGs by triggering PKR phosphorylation, thereby downregulating the translation of antiviral interferon-stimulated genes, and by co-opting SG proteins for its replication, assembly, and egress.

Dicarbonyl stress and glyoxalase enzyme system regulation in human skeletal muscle.

PubMed

Mey, Jacob T; Blackburn, Brian K; Miranda, Edwin R; Chaves, Alec B; Briller, Joan; Bonini, Marcelo G; Haus, Jacob M

2018-02-01

Skeletal muscle insulin resistance is a hallmark of Type 2 diabetes (T2DM) and may be exacerbated by protein modifications by methylglyoxal (MG), known as dicarbonyl stress. The glyoxalase enzyme system composed of glyoxalase 1/2 (GLO1/GLO2) is the natural defense against dicarbonyl stress, yet its protein expression, activity, and regulation remain largely unexplored in skeletal muscle. Therefore, this study investigated dicarbonyl stress and the glyoxalase enzyme system in the skeletal muscle of subjects with T2DM (age: 56 ± 5 yr.; BMI: 32 ± 2 kg/m 2 ) compared with lean healthy control subjects (LHC; age: 27 ± 1 yr.; BMI: 22 ± 1 kg/m 2 ). Skeletal muscle biopsies obtained from the vastus lateralis at basal and insulin-stimulated states of the hyperinsulinemic (40 mU·m -2 ·min -1 )-euglycemic (5 mM) clamp were analyzed for proteins related to dicarbonyl stress and glyoxalase biology. At baseline, T2DM had increased carbonyl stress and lower GLO1 protein expression (-78.8%), which inversely correlated with BMI, percent body fat, and HOMA-IR, while positively correlating with clamp-derived glucose disposal rates. T2DM also had lower NRF2 protein expression (-31.6%), which is a positive regulator of GLO1, while Keap1 protein expression, a negative regulator of GLO1, was elevated (207%). Additionally, insulin stimulation during the clamp had a differential effect on NRF2, Keap1, and MG-modified protein expression. These data suggest that dicarbonyl stress and the glyoxalase enzyme system are dysregulated in T2DM skeletal muscle and may underlie skeletal muscle insulin resistance. Whether these phenotypic differences contribute to the development of T2DM warrants further investigation.

Aspects of acculturation stress among international students attending a university in the USA.

PubMed

Chavajay, Pablo; Skowronek, Jeffrey

2008-12-01

Acculturation stress reported by 130 international students attending a university in Utah for about 2 yr. was examined. On the Acculturative Stress Scale for International Students, few students reported experiencing acculturation stress, but responses to four open-ended questions indicated many students perceived experience of acculturation stresses related to discrimination, feelings of loneliness, and academic concerns. The contrast of findings for the scale scores and the open-ended questions indicate the complexity of assessing international students' acculturation experiences of living and studying in the USA and suggest the usefulness of complementary methodologies for assessing such experience.

Role of serine threonine protein phosphatase type 5 (PP5) in the regulation of stress induced signaling networks and cancer

PubMed Central

Golden, Teresa; Swingle, Mark; Honkanen, Richard E.

2008-01-01

Although the aberrant actions of protein kinases have long been known to contribute to tumor promotion and carcinogenesis, roles for proteins phosphatases in the development of human cancer have only emerged in the last decade. In this review, we discuss the data obtained from studies examining the biological and pathological roles of a serine/threonine protein phosphate, PP5, which suggest that PP5 is a potentially important regulator of both hormone- and stress-induced networks that enable a cell to respond appropriately to genomic stress. PMID:18253812

Protein Mediated Oxidative Stress in Patients with Diabetes and its Associated Neuropathy: Correlation with Protein Carbonylation and Disease Activity Markers

PubMed Central

Almogbel, Ebtehal

2017-01-01

Introduction Free radicals have been implicated as Diabetes Mellitus (DM) contributors in type 2 DM and its associated Diabetes Mellitus Neuropathy (DMN). However, the potential for protein mediated oxidative stress to contribute disease pathogenesis remains largely unexplored. Aim To investigate the status and contribution of protein mediated oxidative stress in patients with DM or DMN and to explore whether oxidative protein modification has a role in DM progression to DM associated neuropathy. Materials and Methods Sera from 42 DM and 37 DMN patients with varying levels of disease activities biomarkers (HbA1C, patients’ age or disease duration) and 21 age- and sex-matched healthy controls were evaluated for serum levels of protein mediated oxidative stress. Results Serum analysis showed significantly higher levels of protein carbonyl contents in both DM and DMN patients compared with healthy controls. Importantly, not only was there an increased number of subjects positive for protein carbonylation, but also the levels of protein carbonyl contents were significantly higher among DM and DMN patients, whose HbA1C were ≥8.8 as compared with patients with lower HbA1C (HbA1C<8.8). Similar pattern of protein carbonyls formation was also observed with patients’ ages or with patient’s disease durations, suggesting a possible relationship between protein oxidation and disease progression. Furthermore, sera from DMN patients had higher levels of protein carbonylation compared with non-neuropathic DM patients’ sera, suggesting an involvement of protein oxidation in the progression of diabetes to diabetes neuropathy. Conclusion These findings support an association between protein oxidation and DM or DMN progression. The stronger response observed in patients with higher HbA1C or patients’ ages or disease durations suggests, that protein mediated oxidative stress may be useful in evaluating the progression of DM and its associated DMN and in elucidating the mechanisms of these disorders pathogenesis. PMID:28384853

The association between occupational stress and depressive symptoms and the mediating role of psychological capital among Chinese university teachers: a cross-sectional study.

PubMed

Shen, Xue; Yang, Yi-Long; Wang, Yang; Liu, Li; Wang, Shu; Wang, Lie

2014-11-30

Depression is a major public health problem that affects both individuals and society. Previous studies report that university teachers are particularly susceptible to high levels of occupational stress and depressive symptoms. The aims of this study were to explore the association between occupational stress and depressive symptoms in a group of university teachers, and assess the mediating role of psychological capital between these variables. A cross-sectional study was performed between November 2013 and January 2014. Teachers from six universities were randomly sampled in Shenyang. The Center for Epidemiologic Studies Depression Scale, effort-reward imbalance scale, and psychological capital questionnaire (PCQ-24), as well as questions about demographic and working factors, were administered in questionnaires distributed to 1,500 university teachers. Completed questionnaires were received from 1,210 participants. Hierarchical linear regression analysis was used to examine the mediating role of psychological capital. In the present study, 58.9% (95% CI (Confidence Intervals): 56.1% to 61.7%) of university teachers had a CES-D score equal to or above the cut-off of 16. Both effort-reward ratio (ERR) and scores of over-commitment were positively associated with depressive symptoms, whereas psychological capital was negatively associated with depressive symptoms among university teachers. Psychological capital partially mediated the relationship between occupational stress and depressive symptoms. Among Chinese university teachers, occupational stress may be a risk factor for depressive symptoms, whereas psychological capital might be protective against depressive symptoms. Our results suggest that college administrators could support the development of psychological capital in their staff to alleviate depressive symptoms.

Comparative proteomic and physiological analyses reveal the protective effect of exogenous polyamines in the bermudagrass (Cynodon dactylon) response to salt and drought stresses.

PubMed

Shi, Haitao; Ye, Tiantian; Chan, Zhulong

2013-11-01

Polyamines conferred enhanced abiotic stress tolerance in multiple plant species. However, the effect of polyamines on abiotic stress and physiological change in bermudagrass, the most widely used warm-season turfgrasses, are unknown. In this study, pretreatment of exogenous polyamine conferred increased salt and drought tolerances in bermudagrass. Comparative proteomic analysis was performed to further investigate polyamines mediated responses, and 36 commonly regulated proteins by at least two types of polyamines in bermudagrass were successfully identified, including 12 proteins with increased level, 20 proteins with decreased level and other 4 specifically expressed proteins. Among them, proteins involved in electron transport and energy pathways were largely enriched, and nucleoside diphosphate kinase (NDPK) and three antioxidant enzymes were extensively regulated by polyamines. Dissection of reactive oxygen species (ROS) levels indicated that polyamine-derived H2O2 production might play dual roles under abiotic stress conditions. Moreover, accumulation of osmolytes was also observed after application of exogenous polyamines, which is consistent with proteomics results that several proteins involved in carbon fixation pathway were mediated commonly by polyamines pretreatment. Taken together, we proposed that polyamines could activate multiple pathways that enhance bermudagrass adaption to salt and drought stresses. These findings might be applicable for genetically engineering of grasses and crops to improve stress tolerance.

Crop and medicinal plants proteomics in response to salt stress

PubMed Central

Aghaei, Keyvan; Komatsu, Setsuko

2013-01-01

Increasing of world population marks a serious need to create new crop cultivars and medicinal plants with high growth and production at any environmental situations. Among the environmental unfavorable conditions, salinity is the most widespread in the world. Crop production and growth severely decreases under salt stress; however, some crop cultivars show significant tolerance against the negative effects of salinity. Among salt stress responses of crops, proteomic responses play a pivotal role in their ability to cope with it and have become the main center of notification. Many physiological responses are detectable in terms of protein increase and decrease even before physiological responses take place. Thus proteomic approach makes a short cut in the way of inferring how crops response to salt stress. Nowadays many salt-responsive proteins such as heat shock proteins, pathogen-related proteins, protein kinases, ascorbate peroxidase, osmotin, ornithine decarboxylase, and some transcription factors, have been detected in some major crops which are thought to give them the ability of withstanding against salt stress. Proteomic analysis of medicinal plants also revealed that alkaloid biosynthesis related proteins such as tryptophan synthase, codeinone reductase, strictosidine synthase, and 12-oxophytodienoate reductase might have major role in production of secondary metabolites. In this review we are comparing some different or similar proteomic responses of several crops and medicinal plants to salt stress and discuss about the future prospects. PMID:23386857

The Relationship between Socio-Demographics and Stress Levels, Stressors, and Coping Mechanisms among Undergraduate Students at a University in Barbados

ERIC Educational Resources Information Center

Persaud, Nadini; Persaud, Indeira

2016-01-01

This study sought to learn about stress experienced by students enrolled in the Faculty of Social Sciences (FSS) at the University of the West Indies (UWI) in Barbados. This research was primarily undertaken to help UWI administrators/academic staff understand and address student stress. One hundred and six FSS students responded to:- (1) student…

Differentially delayed root proteome responses to salt stress in sugar cane varieties.

PubMed

Pacheco, Cinthya Mirella; Pestana-Calsa, Maria Clara; Gozzo, Fabio Cesar; Mansur Custodio Nogueira, Rejane Jurema; Menossi, Marcelo; Calsa, Tercilio

2013-12-06

Soil salinity is a limiting factor to sugar cane crop development, although in general plants present variable mechanisms of tolerance to salinity stress. The molecular basis underlying these mechanisms can be inferred by using proteomic analysis. Thus, the objective of this work was to identify differentially expressed proteins in sugar cane plants submitted to salinity stress. For that, a greenhouse experiment was established with four sugar cane varieties and two salt conditions, 0 mM (control) and 200 mM NaCl. Physiological and proteomics analyses were performed after 2 and 72 h of stress induction by salt. Distinct physiological responses to salinity stress were observed in the varieties and linked to tolerance mechanisms. In proteomic analysis, the roots soluble protein fraction was extracted, quantified, and analyzed through bidimensional electrophoresis. Gel images analyses were done computationally, where in each contrast only one variable was considered (salinity condition or variety). Differential spots were excised, digested by trypsin, and identified via mass spectrometry. The tolerant variety RB867515 showed the highest accumulation of proteins involved in growth, development, carbohydrate and energy metabolism, reactive oxygen species metabolization, protein protection, and membrane stabilization after 2 h of stress. On the other hand, the presence of these proteins in the sensitive variety was verified only in stress treatment after 72 h. These data indicate that these stress responses pathways play a role in the tolerance to salinity in sugar cane, and their effectiveness for phenotypical tolerance depends on early stress detection and activation of the coding genes expression.

Gel-free/label-free proteomic analysis of root tip of soybean over time under flooding and drought stresses.

PubMed

Wang, Xin; Oh, MyeongWon; Sakata, Katsumi; Komatsu, Setsuko

2016-01-01

Growth in the early stage of soybean is markedly inhibited under flooding and drought stresses. To explore the responsive mechanisms of soybean, temporal protein profiles of root tip under flooding and drought stresses were analyzed using gel-free/label-free proteomic technique. Root tip was analyzed because it was the most sensitive organ against flooding, and it was beneficial to root penetration under drought. UDP glucose: glycoprotein glucosyltransferase was decreased and increased in soybean root under flooding and drought, respectively. Temporal protein profiles indicated that fermentation and protein synthesis/degradation were essential in root tip under flooding and drought, respectively. In silico protein-protein interaction analysis revealed that the inductive and suppressive interactions between S-adenosylmethionine synthetase family protein and B-S glucosidase 44 under flooding and drought, respectively, which are related to carbohydrate metabolism. Furthermore, biotin/lipoyl attachment domain containing protein and Class II aminoacyl tRNA/biotin synthetases superfamily protein were repressed in the root tip during time-course stresses. These results suggest that biotin and biotinylation might be involved in energy management to cope with flooding and drought in early stage of soybean-root tip. Copyright © 2015 Elsevier B.V. All rights reserved.

Transformation of plum plants with a cytosolic ascorbate peroxidase transgene leads to enhanced water stress tolerance.

PubMed

Diaz-Vivancos, Pedro; Faize, Lydia; Nicolás, Emilio; Clemente-Moreno, Maria José; Bru-Martinez, Roque; Burgos, Lorenzo; Hernández, José Antonio

2016-06-01

Water deficit is the most serious environmental factor limiting agricultural production. In this work, the tolerance to water stress (WS) of transgenic plum lines harbouring transgenes encoding cytosolic antioxidant enzymes was studied, with the aim of achieving the durable resistance of commercial plum trees. The acclimatization process was successful for two transgenic lines: line C3-1, co-expressing superoxide dismutase (two copies) and ascorbate peroxidase (one copy) transgenes simultaneously; and line J8-1, harbouring four copies of the cytosolic ascorbate peroxidase gene (cytapx). Plant water relations, chlorophyll fluorescence and the levels of antioxidant enzymes were analysed in both lines submitted to moderate (7 d) and severe (15 d) WS conditions. Additionally, in line J8-1, showing the best response in terms of stress tolerance, a proteomic analysis and determination of the relative gene expression of two stress-responsive genes were carried out. Line J8-1 exhibited an enhanced stress tolerance that correlated with better photosynthetic performance and a tighter control of water-use efficiency. Furthermore, this WS tolerance also correlated with a higher enzymatic antioxidant capacity than wild-type (WT) and line C3-1 plum plants. On the other hand, line C3-1 displayed an intermediate phenotype between WT plants and line J8-1 in terms of WS tolerance. Under severe WS, the tolerance displayed by J8-1 plants could be due to an enhanced capacity to cope with drought-induced oxidative stress. Moreover, proteomic analysis revealed differences between WT and J8-1 plants, mainly in terms of the abundance of proteins related to carbohydrate metabolism, photosynthesis, antioxidant defences and protein fate. The transformation of plum plants with cytapx has a profound effect at the physiological, biochemical, proteomic and genetic levels, enhancing WS tolerance. Although further experiments under field conditions will be required, it is proposed that J8-1 plants would be an interesting Prunus rootstock for coping with climate change. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Biogenesis of mitochondria in cauliflower (Brassica oleracea var. botrytis) curds subjected to temperature stress and recovery involves regulation of the complexome, respiratory chain activity, organellar translation and ultrastructure.

PubMed

Rurek, Michal; Woyda-Ploszczyca, Andrzej M; Jarmuszkiewicz, Wieslawa

2015-01-01

The biogenesis of the cauliflower curd mitochondrial proteome was investigated under cold, heat and the recovery. For the first time, two dimensional fluorescence difference gel electrophoresis was used to study the plant mitochondrial complexome in heat and heat recovery. Particularly, changes in the complex I and complex III subunits and import proteins, and the partial disintegration of matrix complexes were observed. The presence of unassembled subunits of ATP synthase was accompanied by impairment in mitochondrial translation of its subunit. In cold and heat, the transcription profiles of mitochondrial genes were uncorrelated. The in-gel activities of respiratory complexes were particularly affected after stress recovery. Despite a general stability of respiratory chain complexes in heat, functional studies showed that their activity and the ATP synthesis yield were affected. Contrary to cold stress, heat stress resulted in a reduced efficiency of oxidative phosphorylation likely due to changes in alternative oxidase (AOX) activity. Stress and stress recovery differently modulated the protein level and activity of AOX. Heat stress induced an increase in AOX activity and protein level, and AOX1a and AOX1d transcript level, while heat recovery reversed the AOX protein and activity changes. Conversely, cold stress led to a decrease in AOX activity (and protein level), which was reversed after cold recovery. Thus, cauliflower AOX is only induced by heat stress. In heat, contrary to the AOX activity, the activity of rotenone-insensitive internal NADH dehydrogenase was diminished. The relevance of various steps of plant mitochondrial biogenesis to temperature stress response and recovery is discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

[Expression of AMPA receptors and related protein in immobilization stressed rats and effect of Xiaoyaosan].

PubMed

Yue, Guang-Xin; Wang, Zhu-Feng; Zhang, Qiao-Li; Zhao, Xin; Yue, Li-Feng; Ding, Jie; Chen, Jia-Xu

2008-05-01

To observe protein expression changes of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor and related regulatory protein in the hippocampus and amygdala in chronic immobilization stressed rat and Xiaoyaosan's regulatory effect. Rats were tied 3 h per day to establish immobilization stress condition and treatment with Xiaoyaosan. After 7 days and 21 days stress, the protein expression of AMPA receptor subunit (GluR2/3), N-ethylmaleimide sensitive factor (NSF) and protein interacting with C-kinase 1 (PICK1) in hippocampus and amygdala were detected by using Western blot techniques. The expression of GluR2/3, NSF in dentate gyrus (DG) and amygdala were markedly attenuated (P < 0.05) and PICK1 in CA1 region were significantly increased (P < 0.05) in 7 d immobilization stressed rats while 7 days xiaoyaosan treatment showed an effective regulatory result to PICK1's changes. Under 21 days immobilization stressed condition, the expression of GluR2/3, NSF in CA1 region showed an increasing trend, and GluR2/3 showed a markedly increase (P < 0.01), but showed an significantly decreased trend in amygdala, Xiaoyaosan showed an effective result to such changes above (P < 0.05). The expression of PICK1 showed increasing trend in amygdala and xiaoyaosan could lower its expression (P < 0.05). There are different trends of the expression of AMPA receptor in repeat short-term stress versus chronic immobilization stress, and in hippocampal CA1 region versus amygdala. Xiaoyaosan has better regulation effect on the expression of AMPA receptors in the condition of chronic immobilization stress than those of repeat shortterm stress.

Stress activates pronociceptive endogenous opioid signalling in DRG neurons during chronic colitis.

PubMed

Guerrero-Alba, Raquel; Valdez-Morales, Eduardo E; Jimenez-Vargas, Nestor N; Lopez-Lopez, Cintya; Jaramillo-Polanco, Josue; Okamoto, Takanobu; Nasser, Yasmin; Bunnett, Nigel W; Lomax, Alan E; Vanner, Stephen J

2017-12-01

Psychological stress accompanies chronic inflammatory diseases such as IBD, and stress hormones can exacerbate pain signalling. In contrast, the endogenous opioid system has an important analgesic action during chronic inflammation. This study examined the interaction of these pathways. Mouse nociceptive dorsal root ganglia (DRG) neurons were incubated with supernatants from segments of inflamed colon collected from patients with chronic UC and mice with dextran sodium sulfate (cDSS)-induced chronic colitis. Stress effects were studied by adding stress hormones (epinephrine and corticosterone) to dissociated neurons or by exposing cDSS mice to water avoidance stress. Changes in excitability of colonic DRG nociceptors were measured using patch clamp and Ca 2+ imaging techniques. Supernatants from patients with chronic UC and from colons of mice with chronic colitis caused a naloxone-sensitive inhibition of neuronal excitability and capsaicin-evoked Ca 2+ responses. Stress hormones decreased signalling induced by human and mouse supernatants. This effect resulted from stress hormones signalling directly to DRG neurons and indirectly through signalling to the immune system, leading to decreased opioid levels and increased acute inflammation. The net effect of stress was a change endogenous opioid signalling in DRG neurons from an inhibitory to an excitatory effect. This switch was associated with a change in G protein-coupled receptor excitatory signalling to a pathway sensitive to inhibitors of protein kinase A-protein, phospholipase C-protein and G protein βϒ subunits. Stress hormones block the inhibitory actions of endogenous opioids and can change the effect of opioid signalling in DRG neurons to excitation. Targeting these pathways may prevent heavy opioid use in IBD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Label-free proteomic analysis to confirm the predicted proteome of Corynebacterium pseudotuberculosis under nitrosative stress mediated by nitric oxide.

PubMed

Silva, Wanderson M; Carvalho, Rodrigo D; Soares, Siomar C; Bastos, Isabela Fs; Folador, Edson L; Souza, Gustavo Hmf; Le Loir, Yves; Miyoshi, Anderson; Silva, Artur; Azevedo, Vasco

2014-12-04

Corynebacterium pseudotuberculosis biovar ovis is a facultative intracellular pathogen, and the etiological agent of caseous lymphadenitis in small ruminants. During the infection process, the bacterium is subjected to several stress conditions, including nitrosative stress, which is caused by nitric oxide (NO). In silico analysis of the genome of C. pseudotuberculosis ovis 1002 predicted several genes that could influence the resistance of this pathogen to nitrosative stress. Here, we applied high-throughput proteomics using high definition mass spectrometry to characterize the functional genome of C. pseudotuberculosis ovis 1002 in the presence of NO-donor Diethylenetriamine/nitric oxide adduct (DETA/NO), with the aim of identifying proteins involved in nitrosative stress resistance. We characterized 835 proteins, representing approximately 41% of the predicted proteome of C. pseudotuberculosis ovis 1002, following exposure to nitrosative stress. In total, 102 proteins were exclusive to the proteome of DETA/NO-induced cells, and a further 58 proteins were differentially regulated between the DETA/NO and control conditions. An interactomic analysis of the differential proteome of C. pseudotuberculosis in response to nitrosative stress was also performed. Our proteomic data set suggested the activation of both a general stress response and a specific nitrosative stress response, as well as changes in proteins involved in cellular metabolism, detoxification, transcriptional regulation, and DNA synthesis and repair. Our proteomic analysis validated previously-determined in silico data for C. pseudotuberculosis ovis 1002. In addition, proteomic screening performed in the presence of NO enabled the identification of a set of factors that can influence the resistance and survival of C. pseudotuberculosis during exposure to nitrosative stress.

Seawater inhalation induces acute lung injury via ROS generation and the endoplasmic reticulum stress pathway.

PubMed

Li, Peng-Cheng; Wang, Bo-Rong; Li, Cong-Cong; Lu, Xi; Qian, Wei-Sheng; Li, Yu-Juan; Jin, Fa-Guang; Mu, De-Guang

2018-05-01

Seawater (SW) inhalation can induce acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In the present study, SW induced apoptosis of rat alveolar epithelial cells and histopathological alterations to lung tissue. Furthermore, SW administration increased generation of reactive oxygen species (ROS), whereas pretreatment with the ROS scavenger, N‑acetyl‑L‑cysteine (NAC), significantly decreased ROS generation, apoptosis and histopathological alterations. In addition, SW exposure upregulated the expression levels of glucose‑regulated protein 78 (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP), which are critical proteins in the endoplasmic reticulum (ER) stress response, thus indicating that SW may activate ER stress. Conversely, blocking ER stress with 4‑phenylbutyric acid (4‑PBA) significantly improved SW‑induced apoptosis and histopathological alterations, whereas an ER stress inducer, thapsigargin, had the opposite effect. Furthermore, blocking ROS with NAC inhibited SW‑induced ER stress, as evidenced by the downregulation of GRP78, phosphorylated (p)‑protein kinase R‑like ER kinase (PERK), p‑inositol‑requiring kinase 1α (IRE1α), p‑50 activating transcription factor 6α and CHOP. In addition, blocking ER stress with 4‑PBA decreased ROS generation. In conclusion, the present study indicated that ROS and ER stress pathways, which are involved in alveolar epithelial cell apoptosis, are important in the pathogenesis of SW‑induced ALI.

[The influence of meaning making following stressful life experiences on change of self-concept].

PubMed

Horita, Ryo; Sugie, Masashi

2013-10-01

As interest in meaning making following stressful life experiences continues to grow, it is important to clarify the features and functions of the meaning- making process. We examined the influence of meaning making following stressful life experiences on change of self-concept. In two studies, university students selected their most stressful life experience and completed the Assimilation and Accommodation of Meaning Making Scale. In Study 1, 235 university students also completed questionnaires regarding post-traumatic growth and positive change of the sense of identity following their stressful life experience. The results of covariance structure analysis indicated that accommodation promoted a positive change of self-concept. In Study 2, 199 university students completed questionnaires regarding change of self-concept and emotion as a positive or negative change following stressful life experiences. The results of covariance structure analysis indicated that accommodation promoted a positive change, similar to the results of Study 1. In addition, accommodation also promoted negative change. However, assimilation did not promote positive change but did restrain negative change.

Influenza A Virus Host Shutoff Disables Antiviral Stress-Induced Translation Arrest

PubMed Central

Khaperskyy, Denys A.; Emara, Mohamed M.; Johnston, Benjamin P.; Anderson, Paul; Hatchette, Todd F.; McCormick, Craig

2014-01-01

Influenza A virus (IAV) polymerase complexes function in the nucleus of infected cells, generating mRNAs that bear 5′ caps and poly(A) tails, and which are exported to the cytoplasm and translated by host machinery. Host antiviral defences include mechanisms that detect the stress of virus infection and arrest cap-dependent mRNA translation, which normally results in the formation of cytoplasmic aggregates of translationally stalled mRNA-protein complexes known as stress granules (SGs). It remains unclear how IAV ensures preferential translation of viral gene products while evading stress-induced translation arrest. Here, we demonstrate that at early stages of infection both viral and host mRNAs are sensitive to drug-induced translation arrest and SG formation. By contrast, at later stages of infection, IAV becomes partially resistant to stress-induced translation arrest, thereby maintaining ongoing translation of viral gene products. To this end, the virus deploys multiple proteins that block stress-induced SG formation: 1) non-structural protein 1 (NS1) inactivates the antiviral double-stranded RNA (dsRNA)-activated kinase PKR, thereby preventing eIF2α phosphorylation and SG formation; 2) nucleoprotein (NP) inhibits SG formation without affecting eIF2α phosphorylation; 3) host-shutoff protein polymerase-acidic protein-X (PA-X) strongly inhibits SG formation concomitant with dramatic depletion of cytoplasmic poly(A) RNA and nuclear accumulation of poly(A)-binding protein. Recombinant viruses with disrupted PA-X host shutoff function fail to effectively inhibit stress-induced SG formation. The existence of three distinct mechanisms of IAV-mediated SG blockade reveals the magnitude of the threat of stress-induced translation arrest during viral replication. PMID:25010204

Monocyte Chemotactic Protein-1 (MCP-1) and Growth Factors Called into Question as Markers of Prolonged Psychosocial Stress

PubMed Central

Jonsdottir, Ingibjörg H.; Hägg, Daniel A.; Glise, Kristina; Ekman, Rolf

2009-01-01

Background Psychosocial stress is becoming a major contributor to increased mental ill-health and sick leave in many countries. Valid markers of chronic stress would be valuable for diagnostic and prognostic purposes. A recent study suggested monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) as markers of chronic stress. We aimed to confirm these potential biomarkers of prolonged psychosocial stress in female patients. Methodology/Principal Findings Circulating levels of MCP-1, EGF and VEGF, along with several other cytokines, were measured in plasma from 42 female patients suffering from exhaustion due to prolonged psychosocial stress and 42 control subjects, using a protein biochip immunoassay. There were no significant differences between patients and controls in any of the cytokines or growth factors analyzed. Furthermore, when using a different protein bioassay and reanalyzing MCP-1 and VEGF in the same samples, markedly different levels were obtained. To further explore if inflammation is present in patients with exhaustion, the classical inflammatory marker C-reactive protein (CRP) was measured in another group of patients (n = 89) and controls (n = 88) showing a small but significant increase of CRP levels in the patients. Conclusions/Significance MCP-1, EGF and VEGF may not be suitable markers of prolonged psychosocial stress as previously suggested. Furthermore, significant differences were obtained when using two different protein assays measuring the same samples, indicating that comparing studies where different analytic techniques have been used might be difficult. Increased levels of CRP indicate that low-grade inflammation might be present in patients with exhaustion due to prolonged stress exposure but this inflammation does not seem to be reflected by increase in circulating MCP-1 or other cytokines measured. PMID:19888340

Wheat proteomics: proteome modulation and abiotic stress acclimation

PubMed Central

Komatsu, Setsuko; Kamal, Abu H. M.; Hossain, Zahed

2014-01-01

Cellular mechanisms of stress sensing and signaling represent the initial plant responses to adverse conditions. The development of high-throughput “Omics” techniques has initiated a new era of the study of plant molecular strategies for adapting to environmental changes. However, the elucidation of stress adaptation mechanisms in plants requires the accurate isolation and characterization of stress-responsive proteins. Because the functional part of the genome, namely the proteins and their post-translational modifications, are critical for plant stress responses, proteomic studies provide comprehensive information about the fine-tuning of cellular pathways that primarily involved in stress mitigation. This review summarizes the major proteomic findings related to alterations in the wheat proteomic profile in response to abiotic stresses. Moreover, the strengths and weaknesses of different sample preparation techniques, including subcellular protein extraction protocols, are discussed in detail. The continued development of proteomic approaches in combination with rapidly evolving bioinformatics tools and interactive databases will facilitate understanding of the plant mechanisms underlying stress tolerance. PMID:25538718

Nanoparticle-induced oxidation of corona proteins initiates an oxidative stress response in cells†

PubMed Central

Jayaram, Dhanya T.; Runa, Sabiha; Kemp, Melissa L.

2017-01-01

Titanium dioxide nanoparticles (TiO2 NPs), used as pigments and photocatalysts, are ubiquitous in our daily lives. Previous work has observed cellular oxidative stress in response to the UV-excitation of photocatalytic TiO2 NPs. In comparison, most human exposure to TiO2 NPs takes place in the dark, in the lung following inhalation or in the gut following consumption of TiO2 NP food pigment. Our spectroscopic characterization shows that both photocatalytic and food grade TiO2 NPs, in the dark, generate low levels of reactive oxygen species (ROS), specifically hydroxyl radicals and superoxides. These ROS oxidize serum proteins that form a corona of proteins on the NP surface. This protein layer is the interface between the NP and the cell. An oxidized protein corona triggers an oxidative stress response, detected with PCR and western blotting. Surface modification of TiO2 NPs to increase or decrease surface defects correlates with ROS generation and oxidative stress, suggesting that NP surface defects, likely oxygen vacancies, are the underlying cause of TiO2 NP-induced oxidative stress. PMID:28537609

The Role of p58IPK in Protecting the Stressed Endoplasmic Reticulum

PubMed Central

Rutkowski, D. Thomas; Kang, Sang-Wook; Goodman, Alan G.; Garrison, Jennifer L.; Taunton, Jack; Katze, Michael G.

2007-01-01

The preemptive quality control (pQC) pathway protects cells from acute endoplasmic reticulum (ER) stress by attenuating translocation of nascent proteins despite their targeting to translocons at the ER membrane. Here, we investigate the hypothesis that the DnaJ protein p58IPK plays an essential role in this process via HSP70 recruitment to the cytosolic face of translocons for extraction of translocationally attenuated nascent chains. Our analyses revealed that the heightened stress sensitivity of p58−/− cells was not due to an impairment of the pQC pathway or elevated ER substrate burden during acute stress. Instead, the lesion was in the protein processing capacity of the ER lumen, where p58IPK was found to normally reside in association with BiP. ER lumenal p58IPK could be coimmunoprecipitated with a newly synthesized secretory protein in vitro and stimulated protein maturation upon overexpression in cells. These results identify a previously unanticipated location for p58IPK in the ER lumen where its putative function as a cochaperone explains the stress-sensitivity phenotype of knockout cells and mice. PMID:17567950

Endoplasmic Reticulum Stress Caused by Lipoprotein Accumulation Suppresses Immunity against Bacterial Pathogens and Contributes to Immunosenescence

PubMed Central

Singh, Jogender

2017-01-01

ABSTRACT The unfolded protein response (UPR) is a stress response pathway that is activated upon increased unfolded and/or misfolded proteins in the endoplasmic reticulum (ER), and enhanced ER stress response prolongs life span and improves immunity. However, the mechanism by which ER stress affects immunity remains poorly understood. Using the nematode Caenorhabditis elegans, we show that mutations in the lipoproteins vitellogenins, which are homologs of human apolipoprotein B-100, resulted in upregulation of the UPR. Lipoprotein accumulation in the intestine adversely affects the immune response and the life span of the organism, suggesting that it could be a contributing factor to immunosenescence. We show that lipoprotein accumulation inhibited the expression of several immune genes encoding proteins secreted by the intestinal cells in an IRE-1-independent manner. Our studies provide a mechanistic explanation for adverse effects caused by protein aggregation and ER stress on immunity and highlight the role of an IRE-1-independent pathway in the suppression of the expression of genes encoding secreted proteins. PMID:28559483

MCP-1 causes cardiomyoblast death via autophagy resulting from ER stress caused by oxidative stress generated by inducing a novel zinc-finger protein, MCPIP.

PubMed

Younce, Craig W; Kolattukudy, Pappachan E

2010-01-27

MCP-1 (monocyte chemotactic protein-1) plays a critical role in the development of heart failure that is known to involve apoptosis. How MCP-1 contributes to cell death involved in the development of heart disease is not understood. In the present study we show that MCP-1 causes death in cardiac myoblasts, H9c2 cells, by inducing oxidative stress which causes ER stress leading to autophagy via a novel zinc-finger protein, MCPIP (MCP-1-induced protein). MCPIP expression caused cell death, and knockdown of MCPIP attenuated MCP-1-induced cell death. It caused induction of iNOS (inducible NO synthase), translocation of the NADPH oxidase subunit phox47 from the cytoplasm to the membrane, production of ROS (reactive oxygen species), and induction of ER (endoplasmic reticulum) stress markers HSP40 (heat-shock protein 40), PDI (protein disulfide-isomerase), GRP78 (guanine-nucleotide-releasing protein 78) and IRE1alpha (inositol-requiring enzyme 1alpha). It also caused autophagy, as indicated by beclin-1 induction, cleavage of LC3 (microtubule-associated protein 1 light chain 3) and autophagolysosome formation, and apoptosis, as indicated by caspase 3 activation and TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP nick-end labelling) assay. Inhibitors of oxidative stress, including CeO2 nanoparticles, inhibited ROS formation, ER stress, autophagy and cell death. Specific inhibitors of ER stress inhibited autophagy and cell death as did knockdown of the ER stress signalling protein IRE1. Knockdown of beclin-1 and autophagy inhibitors prevented cell death. This cell death involved caspase 2 and caspase 12, as specific inhibitors of these caspases prevented MCPIP-induced cell death. Microarray analysis showed that MCPIP expression caused induction of a variety of genes known to be involved in cell death. MCPIP caused activation of JNK (c-Jun N-terminal kinase) and p38 and induction of p53 and PUMA (p53 up-regulated modulator of apoptosis). Taken together, these results suggest that MCPIP induces ROS/RNS (reactive nitrogen species) production that causes ER stress which leads to autophagy and apoptosis through caspase 2/12 and IRE1alpha-JNK/p38-p53-PUMA pathway. These results provide the first molecular insights into the mechanism by which elevated MCP-1 levels associated with chronic inflammation may contribute to the development of heart failure.

Arsenite-induced autophagy is associated with proteotoxicity in human lymphoblastoid cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolt, Alicia M.; Zhao, Fei; Pacheco, Samantha

2012-10-15

Epidemiological studies of arsenic-exposed populations have provided evidence that arsenic exposure in humans is associated with immunosuppression. Previously, we have reported that arsenite-induced toxicity is associated with the induction of autophagy in human lymphoblastoid cell lines (LCL). Autophagy is a cellular process that functions in the degradation of damaged cellular components, including protein aggregates formed by misfolded or damaged proteins. Accumulation of misfolded or damaged proteins in the endoplasmic reticulum (ER) lumen causes ER stress and activates the unfolded protein response (UPR). In an effort to investigate the mechanism of autophagy induction by arsenite in the LCL model, we examinedmore » the potential contribution of ER stress and activation of the UPR. LCL exposed to sodium arsenite for 8-days induced expression of UPR-activated genes, including CHOP and GRP78, at the RNA and the protein level. Evidence for activation of the three arms of the UPR was observed. The arsenite-induced activation of the UPR was associated with an accumulation of protein aggregates containing p62 and LC3, proteins with established roles in the sequestration and autophagic clearance of protein aggregates. Taken together, these data provide evidence that arsenite-induced autophagy is associated with the generation of ER stress, activation of the UPR, and formation of protein aggregates that may be targeted to the lysosome for degradation. -- Highlights: ► Arsenite induces endoplasmic reticulum stress and the unfolded protein response. ► Arsenite induces the formation of protein aggregates that contain p62 and LC3-II. ► Time-course data suggests that arsenite-induced autophagy precedes ER stress.« less

Overexpression of heat shock GroEL stress protein in leptospiral biofilm.

PubMed

Vinod Kumar, K; Lall, Chandan; Vimal Raj, R; Vedhagiri, K; Kartick, C; Surya, P; Natarajaseenivasan, K; Vijayachari, P

2017-01-01

Leptospira is the causative agent of leptospirosis, which is an emerging zoonotic disease. Recent studies on Leptospira have demonstrated biofilm formation on abiotic surfaces. The protein expressed in the biofilm was investigated by using SDS-PAGE and immunoblotting in combination with MALDI-TOF mass spectrometry. The proteins expressed in Leptospira biofilm and planktonic cells was analyzed and compared. Among these proteins, one (60 kDa) was found to overexpress in biofilm as compared to the planktonic cells. MALDI-TOF analysis identified this protein as stress and heat shock chaperone GroEL. Our findings demonstrate that GroEL is associated with Leptospira biofilm. GroEL is conserved, highly immunogenic and a prominent stress response protein in pathogenic Leptospira spp., which may have clinical relevance. Copyright © 2016 Elsevier Ltd. All rights reserved.

The eIF4E-binding proteins are modifiers of cytoplasmic eIF4E relocalization during the heat shock response.

PubMed

Sukarieh, R; Sonenberg, N; Pelletier, J

2009-05-01

Stress granules (SGs) arise as a consequence of cellular stress, contain stalled translation preinitiation complexes, and are associated with cell survival during environmental insults. SGs are dynamic entities with proteins relocating into and out of them during stress. Among the repertoire of proteins present in SGs is eukaryotic initiation factor 4E (eIF4E), a translation factor required for cap-dependent translation and that regulates a rate-limiting step for protein synthesis. Herein, we demonstrate that localization of eIF4E to SGs is dependent on the presence of a family of repressor proteins, eIF4E-binding proteins (4E-BPs). Our results demonstrate that 4E-BPs regulate the SG localization of eIF4E.

iTRAQ-Based Quantitative Proteomic Analysis of Spirulina platensis in Response to Low Temperature Stress

PubMed Central

Li, Qingye; Chang, Rong; Sun, Yijun; Li, Bosheng

2016-01-01

Low temperature (LT) is one of the most important abiotic stresses that can significantly reduce crop yield. To gain insight into how Spirulina responds to LT stress, comprehensive physiological and proteomic analyses were conducted in this study. Significant decreases in growth and pigment levels as well as excessive accumulation of compatible osmolytes were observed in response to LT stress. An isobaric tag for relative and absolute quantitation (iTRAQ)-based quantitative proteomics approach was used to identify changes in protein abundance in Spirulina under LT. A total of 3,782 proteins were identified, of which 1,062 showed differential expression. Bioinformatics analysis indicated that differentially expressed proteins that were enriched in photosynthesis, carbohydrate metabolism, amino acid biosynthesis, and translation are important for the maintenance of cellular homeostasis and metabolic balance in Spirulina when subjected to LT stress. The up-regulation of proteins involved in gluconeogenesis, starch and sucrose metabolism, and amino acid biosynthesis served as coping mechanisms of Spirulina in response to LT stress. Moreover, the down-regulated expression of proteins involved in glycolysis, TCA cycle, pentose phosphate pathway, photosynthesis, and translation were associated with reduced energy consumption. The findings of the present study allow a better understanding of the response of Spirulina to LT stress and may facilitate in the elucidation of mechanisms underlying LT tolerance. PMID:27902743

iTRAQ-Based Quantitative Proteomic Analysis of Spirulina platensis in Response to Low Temperature Stress.

PubMed

Li, Qingye; Chang, Rong; Sun, Yijun; Li, Bosheng

2016-01-01

Low temperature (LT) is one of the most important abiotic stresses that can significantly reduce crop yield. To gain insight into how Spirulina responds to LT stress, comprehensive physiological and proteomic analyses were conducted in this study. Significant decreases in growth and pigment levels as well as excessive accumulation of compatible osmolytes were observed in response to LT stress. An isobaric tag for relative and absolute quantitation (iTRAQ)-based quantitative proteomics approach was used to identify changes in protein abundance in Spirulina under LT. A total of 3,782 proteins were identified, of which 1,062 showed differential expression. Bioinformatics analysis indicated that differentially expressed proteins that were enriched in photosynthesis, carbohydrate metabolism, amino acid biosynthesis, and translation are important for the maintenance of cellular homeostasis and metabolic balance in Spirulina when subjected to LT stress. The up-regulation of proteins involved in gluconeogenesis, starch and sucrose metabolism, and amino acid biosynthesis served as coping mechanisms of Spirulina in response to LT stress. Moreover, the down-regulated expression of proteins involved in glycolysis, TCA cycle, pentose phosphate pathway, photosynthesis, and translation were associated with reduced energy consumption. The findings of the present study allow a better understanding of the response of Spirulina to LT stress and may facilitate in the elucidation of mechanisms underlying LT tolerance.

Roles of mitochondrial energy dissipation systems in plant development and acclimation to stress.

PubMed

Pu, Xiaojun; Lv, Xin; Tan, Tinghong; Fu, Faqiong; Qin, Gongwei; Lin, Honghui

2015-09-01

Plants are sessile organisms that have the ability to integrate external cues into metabolic and developmental signals. The cues initiate specific signal cascades that can enhance the tolerance of plants to stress, and these mechanisms are crucial to the survival and fitness of plants. The adaption of plants to stresses is a complex process that involves decoding stress inputs as energy-deficiency signals. The process functions through vast metabolic and/or transcriptional reprogramming to re-establish the cellular energy balance. Members of the mitochondrial energy dissipation pathway (MEDP), alternative oxidases (AOXs) and uncoupling proteins (UCPs), act as energy mediators and might play crucial roles in the adaption of plants to stresses. However, their roles in plant growth and development have been relatively less explored. This review summarizes current knowledge about the role of members of the MEDP in plant development as well as recent advances in identifying molecular components that regulate the expression of AOXs and UCPs. Highlighted in particular is a comparative analysis of the expression, regulation and stress responses between AOXs and UCPs when plants are exposed to stresses, and a possible signal cross-talk that orchestrates the MEDP, reactive oxygen species (ROS), calcium signalling and hormone signalling. The MEDP might act as a cellular energy/metabolic mediator that integrates ROS signalling, energy signalling and hormone signalling with plant development and stress accumulation. However, the regulation of MEDP members is complex and occurs at transcriptional, translational, post-translational and metabolic levels. How this regulation is linked to actual fluxes through the AOX/UCP in vivo remains elusive. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Examining the Impact of a University-driven Exercise Programming Event on End-of-semester Stress in Students.

PubMed

Koschel, Tessa L; Young, John C; Navalta, James W

2017-01-01

Stress levels in university students peak during the final exam period. An inverse association exists between Physical Activity (PA) and poor mental health. UNLV has created Fitness4Finals (F4F), an event novel in its approach to academic stress reduction by incorporating both physical activity and mental relaxation. To our knowledge, a university-driven programming event aimed at reducing physiological and psychological stress among students approaching final exams had never been studied. Therefore, the aims of this research were to 1) examine the influence of F4F on physiological stress and perceived psychological stress (PPS) and 2) to examine the relationship between physiological stress and PPS. Fifteen full-time university students were recruited to participate in their choice of one of two groups: F4F or control (NonF4F). Pre-F4F and post-F4F measures of physiological stress, measured by salivary cortisol, and perceived psychological stress, measured by survey were collected. The F4F event was held the week prior to final examinations. Participants in the F4F group engaged in one F4F activity per day for the duration of the 3-day event. Results of the repeated measures MANOVA indicated nonsignificant interaction (p = .864) between F4F participation, physiological stress and PPS. PPS and cortisol were not correlated at the onset of the study (r = -0.18, p = 0.48) or at the last sampling period (r = 0.097, p = 0.73). Preemptive elevated levels of PA in the F4F group may have influenced results. Qualitative data indicates a unanimous perceived reduction in stress from F4F participation. While the physiological measures of stress in the present study were not significantly different, the perceived stress reduction reported by F4F participants is influential. Further investigation with improvements in timing and measurement tools is warranted.

Introgression of the SbASR-1 Gene Cloned from a Halophyte Salicornia brachiata Enhances Salinity and Drought Endurance in Transgenic Groundnut (Arachis hypogaea) and Acts as a Transcription Factor

PubMed Central

Tiwari, Vivekanand; Chaturvedi, Amit Kumar; Mishra, Avinash; Jha, Bhavanath

2015-01-01

The SbASR-1 gene, cloned from a halophyte Salicornia brachiata, encodes a plant-specific hydrophilic and stress responsive protein. The genome of S. brachiata has two paralogs of the SbASR-1 gene (2549 bp), which is comprised of a single intron of 1611 bp, the largest intron of the  abscisic acid stress ripening [ASR] gene family yet reported. In silico analysis of the 843-bp putative promoter revealed the presence of ABA, biotic stress, dehydration, phytohormone, salinity, and sugar responsive cis-regulatory motifs. The SbASR-1 protein belongs to Group 7 LEA protein family with different amino acid composition compared to their glycophytic homologs. Bipartite Nuclear Localization Signal (NLS) was found on the C-terminal end of protein and localization study confirmed that SbASR-1 is a nuclear protein. Furthermore, transgenic groundnut (Arachis hypogaea) plants over-expressing the SbASR-1 gene constitutively showed enhanced salinity and drought stress tolerance in the T1 generation. Leaves of transgenic lines exhibited higher chlorophyll and relative water contents and lower electrolyte leakage, malondialdehyde content, proline, sugars, and starch accumulation under stress treatments than wild-type (Wt) plants. Also, lower accumulation of H2O2 and O2 .- radicals was detected in transgenic lines compared to Wt plants under stress conditions. Transcript expression of APX (ascorbate peroxidase) and CAT (catalase) genes were higher in Wt plants, whereas the SOD (superoxide dismutase) transcripts were higher in transgenic lines under stress. Electrophoretic mobility shift assay (EMSA) confirmed that the SbASR-1 protein binds at the consensus sequence (C/G/A)(G/T)CC(C/G)(C/G/A)(A/T). Based on results of the present study, it may be concluded that SbASR-1 enhances the salinity and drought stress tolerance in transgenic groundnut by functioning as a LEA (late embryogenesis abundant) protein and a transcription factor. PMID:26158616

Gender differences in stressors and reactions to stressors among Jordanian university students.

PubMed

Hamaideh, Shaher H

2012-01-01

Stress among university students has been a topic of interest for researchers and teachers for many years because it affects not only their academic performance but also their physiological and psychological health. Male and female students perceive and react to stressors differently due to their differences in appraising stressful situations. The aims of this study were to examine differences in the perception of stressors and reactions to stressors between male and female Jordanian university students, and to identify the best predictors of stressors among them. Descriptive cross-sectional design was employed. The Student-Life Stress Inventory was used to measure stressors and reactions to stressors of 465 male and 485 female Jordanian university students recruited through stratified random sampling. There were statistical differences between male and female students regarding their perception and reactions to stressors. Female students reported a higher perception of stressors in frustrations, conflict, pressures and changes, as well as emotional reactions to stressors. Male students reported higher behavioural and cognitive reactions to stressors than female students. Participation in stress workshops, perception of general health, and perception of stress level in general were found to predict stressors among male students, while mother's educational level, perception of general health, and perception of stress level in general were found to predict stressors among female students. This study showed that gender differences in perception of stressors and reactions to stressors are similar to previous studies conducted all over the world. Interventions can be developed to help students better cope with stress. Conducting specific stress-training programmes for male and female students will help in reducing stress levels.

Descriptive study of stress and satisfaction at work in the Saragossa university services and administration staff

PubMed Central

2010-01-01

Background The notion of stress in connection with the work environment became an important topic during the 1970's, when the first studies on the subject were published and the term of work stress was first coined. In 1974, Freudenberger proposed the term burnout to refer to the condition of physical and emotional exhaustion, as well as the associated negative attitudes, resulting from the intense interaction in working with people. The aim of our study is to examine burnout and job satisfaction in Saragossa University Services and Administration Staff (SAS) and detect the main factors which could contribute to too much stress, because job stress has emerged as a major psychosocial influence on mental health, associated with burnout. Methods 24 people from the Services and Administration Staff in the University of Saragossa participated in the study. The research was carried out during the implementation of a module on Stress Management organised by the University of Saragossa and commissioned to the Unit for Research in Physical Therapy (University School of Health Sciences) from that University. This research is an exploratory research to improve the stress management program. A personal interview was carried out and additionally, participants were given the Maslach Burnout Inventory and the Scale of Satisfaction at Work of Warr, Cook & Wall. Results However using small sample this is worth to state that participants present most of them low burnout levels in the burnout scale. Only in one person high exhaustion level was reflected, even though other seven showed mean levels; in the professional self-esteem section, most of them showed high self-esteem, with two cases of low self-esteem and five with mean level. With regard to satisfaction people participating in the study show mean levels in intrinsic as much as in extrinsic factors and general satisfaction. Conclusions Services and Administration Staff from the University of Saragossa shows low burnout levels linked with high professional self-esteem and low emotional exhaustion and depersonalization. It has been found also medium levels in work satisfaction probably related with the continuous quality improvement efforts in the academics environment to create protective factors in decreasing levels of job stress. These results show that not only personality or temperament have an influence on burnout and stress, also the job conditions are related with these diseases. These aspects should be taken into account in the design of stress prevention programme at work. PMID:20409314

System-wide Analysis of SUMOylation Dynamics in Response to Replication Stress Reveals Novel Small Ubiquitin-like Modified Target Proteins and Acceptor Lysines Relevant for Genome Stability*

PubMed Central

Xiao, Zhenyu; Chang, Jer-Gung; Hendriks, Ivo A.; Sigurðsson, Jón Otti; Olsen, Jesper V.; Vertegaal, Alfred C.O.

2015-01-01

Genotoxic agents can cause replication fork stalling in dividing cells because of DNA lesions, eventually leading to replication fork collapse when the damage is not repaired. Small Ubiquitin-like Modifiers (SUMOs) are known to counteract replication stress, nevertheless, only a small number of relevant SUMO target proteins are known. To address this, we have purified and identified SUMO-2 target proteins regulated by replication stress in human cells. The developed methodology enabled single step purification of His10-SUMO-2 conjugates under denaturing conditions with high yield and high purity. Following statistical analysis on five biological replicates, a total of 566 SUMO-2 targets were identified. After 2 h of hydroxyurea treatment, 10 proteins were up-regulated for SUMOylation and two proteins were down-regulated for SUMOylation, whereas after 24 h, 35 proteins were up-regulated for SUMOylation, and 13 proteins were down-regulated for SUMOylation. A site-specific approach was used to map over 1000 SUMO-2 acceptor lysines in target proteins. The methodology is generic and is widely applicable in the ubiquitin field. A large subset of these identified proteins function in one network that consists of interacting replication factors, transcriptional regulators, DNA damage response factors including MDC1, ATR-interacting protein ATRIP, the Bloom syndrome protein and the BLM-binding partner RMI1, the crossover junction endonuclease EME1, BRCA1, and CHAF1A. Furthermore, centromeric proteins and signal transducers were dynamically regulated by SUMOylation upon replication stress. Our results uncover a comprehensive network of SUMO target proteins dealing with replication damage and provide a framework for detailed understanding of the role of SUMOylation to counteract replication stress. Ultimately, our study reveals how a post-translational modification is able to orchestrate a large variety of different proteins to integrate different nuclear processes with the aim of dealing with the induced DNA damage. PMID:25755297

Suppression of NF-κB signal pathway by NLRC3-like protein in stony coral Acropora aculeus under heat stress.

PubMed

Zhou, Zhi; Wu, Yibo; Zhang, Chengkai; Li, Can; Chen, Guangmei; Yu, Xiaopeng; Shi, Xiaowei; Xu, Yanlai; Wang, Lingui; Huang, Bo

2017-08-01

Heat stress is the most common factor for coral bleaching, which has increased both in frequency and severity due to global warming. In the present study, the stony coral Acropora aculeus was subjected to acute heat stress and entire transcriptomes were sequenced via the next generation sequencing platform. Four paired-end libraries were constructed and sequenced in two groups, including a control and a heat stress group. A total of 120,319,751 paired-end reads with lengths of 2 × 100 bp were assembled and 55,021 coral-derived genes were obtained. After read mapping and abundance estimation, 9110 differentially expressed genes were obtained in the comparison between the control and heat stress group, including 4465 significantly upregulated and 4645 significantly downregulated genes. Twenty-three GO terms in the Biological Process category were overrepresented for significantly upregulated genes, and divided into six groups according to their relationship. These three groups were related to the NF-κB signal pathway, and the remaining three groups were relevant for pathogen response, immunocyte activation and protein ubiquitination. Forty-three common genes were found in four GO terms, which were directly related to the NF-κB signal pathway. These included 2 NACHT, LRR, PYD domains-containing protein, 5 nucleotide-binding oligomerization domain-containing protein, 29 NLRC3-like protein, 4 NLRC5-like protein, and 3 uncharacterized protein. For significantly downregulated genes, 27 overrepresented GO terms were found in the Biological Process category, which were relevant to protein ubiquitination and ATP metabolism. Our results indicate that heat stress suppressed the immune response level via the NLRC3-like protein, the fine-tuning of protein turnover activity, and ATP metabolism. This might disrupt the balance of coral-zooxanthellae symbiosis and result in the bleaching of the coral A. aculeus. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative proteomic analysis of rd29A:RdreB1BI transgenic and non-transgenic strawberries exposed to low temperature.

PubMed

Gu, Xianbin; Gao, Zhihong; Zhuang, Weibing; Qiao, Yushan; Wang, Xiuyun; Mi, Lin; Zhang, Zhen; Lin, Zhilin

2013-05-01

Low-temperature stress is one of the major abiotic stresses in plants worldwide, and the dehydration responsive element binding protein (DREB) transcription factor induces expression of genes involved in environmental stress tolerance in plants. A proteomic approach based on two-dimensional gel electrophoresis (2-DE) and subsequent mass spectrometric identification was used to study the changes in the leaf proteome profiles of rd29A:RdreB1BI transgenic and non-transgenic strawberries exposed to low-temperature conditions. By comparing the proteomic profiles, we located 21 protein spots that were reproducibly up- or down-regulated by more than twofold between transgenic and non-transgenic strawberries. Eight identified proteins function in energy and metabolism, four in biosynthetic processes, four were stress and defense related, three spots were identified as cold-stress related expressed sequence tags (ESTs), and two were unknown proteins. The change patterns of low-temperature tolerance proteins, including photosynthetic proteins (RuBisCO large subunit and RuBisCO activase), cytoplasmic Cu/Zn-superoxide dismutase (Cu/Zn-SOD), late embryogenesis abundant protein 14-A (Lea14-A), eukaryotic translation initiation factor 5A (eIF5A), and cold-stress related ESTs, were differentially regulated between non-transgenic and rd29A:RdreB1BI transgenic strawberries. They are likely important gene products in the regulatory network of the RdreB1BI gene. Consequently, this study provides the first characterization of the transgenic strawberry proteome and the predicted target proteins of the RdreB1BI gene by using proteomic approaches. Copyright © 2013 Elsevier GmbH. All rights reserved.

Patterns of gene expression associated with recovery and injury in heat-stressed rats.

PubMed

Stallings, Jonathan D; Ippolito, Danielle L; Rakesh, Vineet; Baer, Christine E; Dennis, William E; Helwig, Bryan G; Jackson, David A; Leon, Lisa R; Lewis, John A; Reifman, Jaques

2014-12-03

The in vivo gene response associated with hyperthermia is poorly understood. Here, we perform a global, multiorgan characterization of the gene response to heat stress using an in vivo conscious rat model. We heated rats until implanted thermal probes indicated a maximal core temperature of 41.8°C (Tc,Max). We then compared transcriptomic profiles of liver, lung, kidney, and heart tissues harvested from groups of experimental animals at Tc,Max, 24 hours, and 48 hours after heat stress to time-matched controls kept at an ambient temperature. Cardiac histopathology at 48 hours supported persistent cardiac injury in three out of six animals. Microarray analysis identified 78 differentially expressed genes common to all four organs at Tc,Max. Self-organizing maps identified gene-specific signatures corresponding to protein-folding disorders in heat-stressed rats with histopathological evidence of cardiac injury at 48 hours. Quantitative proteomics analysis by iTRAQ (isobaric tag for relative and absolute quantitation) demonstrated that differential protein expression most closely matched the transcriptomic profile in heat-injured animals at 48 hours. Calculation of protein supersaturation scores supported an increased propensity of proteins to aggregate for proteins that were found to be changing in abundance at 24 hours and in animals with cardiac injury at 48 hours, suggesting a mechanistic association between protein misfolding and the heat-stress response. Pathway analyses at both the transcript and protein levels supported catastrophic deficits in energetics and cellular metabolism and activation of the unfolded protein response in heat-stressed rats with histopathological evidence of persistent heat injury, providing the basis for a systems-level physiological model of heat illness and recovery.

Quantitative proteome profile of water deficit stress responses in eastern cottonwood ( Populus deltoides) leaves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abraham, Paul E.; Garcia, Benjamin J.; Gunter, Lee E.

Drought stress is a recurring feature of world climate and the single most important factor influencing agricultural yield worldwide. Plants display highly variable, species-specific responses to drought and these responses are multifaceted, requiring physiological and morphological changes influenced by genetic and molecular mechanisms. Moreover, the reproducibility of water deficit studies is very cumbersome, which significantly impedes research on drought tolerance, because how a plant responds is highly influenced by the timing, duration, and intensity of the water deficit. Despite progress in the identification of drought-related mechanisms in many plants, the molecular basis of drought resistance remains to be fully understoodmore » in trees, particularly in poplar species because their wide geographic distribution results in varying tolerances to drought. Herein, we aimed to better understand this complex phenomenon in eastern cottonwood ( Populus deltoides) by performing a detailed contrast of the proteome changes between two different water deficit experiments to identify functional intersections and divergences in proteome responses. We investigated plants subjected to cyclic water deficit and compared these responses to plants subjected to prolonged acute water deficit. In total, we identified 108,012 peptide sequences across both experiments that provided insight into the quantitative state of 22,737 Populus gene models and 8,199 functional protein groups in response to drought. Together, these datasets provide the most comprehensive insight into proteome drought responses in poplar to date and a direct proteome comparison between short period dehydration shock and cyclic, post-drought re-watering. Altogether, this investigation provides novel insights into drought avoidance mechanisms that are distinct from progressive drought stress. Additionally, we identified proteins that have been associated as drought-relevant in previous studies. Importantly, we highlight the RD26 transcription factor as a gene regulated at both the transcript and protein level, regardless of species and drought condition, and, thus, represents a key, universal drought marker for Populus species.« less

Quantitative proteome profile of water deficit stress responses in eastern cottonwood ( Populus deltoides) leaves

DOE PAGES

Abraham, Paul E.; Garcia, Benjamin J.; Gunter, Lee E.; ...

2018-02-15

Drought stress is a recurring feature of world climate and the single most important factor influencing agricultural yield worldwide. Plants display highly variable, species-specific responses to drought and these responses are multifaceted, requiring physiological and morphological changes influenced by genetic and molecular mechanisms. Moreover, the reproducibility of water deficit studies is very cumbersome, which significantly impedes research on drought tolerance, because how a plant responds is highly influenced by the timing, duration, and intensity of the water deficit. Despite progress in the identification of drought-related mechanisms in many plants, the molecular basis of drought resistance remains to be fully understoodmore » in trees, particularly in poplar species because their wide geographic distribution results in varying tolerances to drought. Herein, we aimed to better understand this complex phenomenon in eastern cottonwood ( Populus deltoides) by performing a detailed contrast of the proteome changes between two different water deficit experiments to identify functional intersections and divergences in proteome responses. We investigated plants subjected to cyclic water deficit and compared these responses to plants subjected to prolonged acute water deficit. In total, we identified 108,012 peptide sequences across both experiments that provided insight into the quantitative state of 22,737 Populus gene models and 8,199 functional protein groups in response to drought. Together, these datasets provide the most comprehensive insight into proteome drought responses in poplar to date and a direct proteome comparison between short period dehydration shock and cyclic, post-drought re-watering. Altogether, this investigation provides novel insights into drought avoidance mechanisms that are distinct from progressive drought stress. Additionally, we identified proteins that have been associated as drought-relevant in previous studies. Importantly, we highlight the RD26 transcription factor as a gene regulated at both the transcript and protein level, regardless of species and drought condition, and, thus, represents a key, universal drought marker for Populus species.« less

Biochemical modifications in Pinus pinaster Ait. as a result of environmental pollution.

PubMed

Acquaviva, Rosaria; Vanella, Luca; Sorrenti, Valeria; Santangelo, Rosa; Iauk, Liliana; Russo, Alessandra; Savoca, Francesca; Barbagallo, Ignazio; Di Giacomo, Claudia

2012-11-01

Exposure to chemical pollution can cause significant damage to plants by imposing conditions of oxidative stress. Plants combat oxidative stress by inducing antioxidant metabolites, enzymatic scavengers of activated oxygen and heat shock proteins. The accumulation of these proteins, in particular heat shock protein 70 and heme oxygenase, is correlated with the acquisition of thermal and chemical adaptations and protection against oxidative stress. In this study, we used Pinus pinaster Ait. collected in the areas of Priolo and Aci Castello representing sites with elevated pollution and reference conditions, respectively. The presence of heavy metals and the levels of markers of oxidative stress (lipid hydroperoxide levels, thiol groups, superoxide dismutase activity and expression of heat shock protein 70, heme oxygenase and superoxide dismutase) were evaluated, and we measured in field-collected needles the response to environmental pollution. P. pinaster Ait. collected from a site characterized by industrial pollution including heavy metals had elevated stress response as indicated by significantly elevated lipid hydroperoxide levels and decreased thiol groups. In particular, we observed that following a chronic chemical exposure, P. pinaster Ait. showed significantly increased expression of heat shock protein 70, heme oxygenase and superoxide dismutase. This increased expression may have protective effects against oxidative stress and represents an adaptative cellular defence mechanism. These results suggest that evaluation of heme oxygenase, heat shock protein 70 and superoxide dismutase expression in P. pinaster Ait. could represent a useful tool for monitoring environmental contamination of a region and to better understand mechanisms involved in plant defence and stress tolerance.

The Batten disease gene CLN3 confers resistance to endoplasmic reticulum stress induced by tunicamycin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Dan, E-mail: danw@bjmu.edu.cn; Liu, Jing; Wu, Baiyan

2014-04-25

Highlights: • The work reveals a protective properties of CLN3 towards TM-induced apoptosis. • CLN3 regulates expression of the GRP78 and the CHOP in response to the ER stress. • CLN3 plays a specific role in the ERS response. - Abstract: Mutations in CLN3 gene cause juvenile neuronal ceroid lipofuscinosis (JNCL or Batten disease), an early-onset neurodegenerative disorder that is characterized by the accumulation of ceroid lipofuscin within lysosomes. The function of the CLN3 protein remains unclear and is presumed to be related to Endoplasmic reticulum (ER) stress. To investigate the function of CLN3 in the ER stress signaling pathway,more » we measured proliferation and apoptosis in cells transfected with normal and mutant CLN3 after treatment with the ER stress inducer tunicamycin (TM). We found that overexpression of CLN3 was sufficient in conferring increased resistance to ER stress. Wild-type CLN3 protected cells from TM-induced apoptosis and increased cell proliferation. Overexpression of wild-type CLN3 enhanced expression of the ER chaperone protein, glucose-regulated protein 78 (GRP78), and reduced expression of the proapoptotic protein CCAAT/-enhancer-binding protein homologous protein (CHOP). In contrast, overexpression of mutant CLN3 or siRNA knockdown of CLN3 produced the opposite effect. Together, our data suggest that the lack of CLN3 function in cells leads to a failure of management in the response to ER stress and this may be the key deficit in JNCL that causes neuronal degeneration.« less

Mindfulness, Stress, and Coping among University Students

ERIC Educational Resources Information Center

Palmer, Angele; Rodger, Susan

2009-01-01

A sample of 135 first-year university students living in residence completed questionnaires that measured individual differences in mindfulness, coping styles, and perceived stress. Findings revealed significant positive relationships between mindfulness and rational coping, and significant negative relationships with emotional and avoidant coping…

New insights on the functional role of URG7 in the cellular response to ER stress.

PubMed

Armentano, Maria Francesca; Caterino, Marianna; Miglionico, Rocchina; Ostuni, Angela; Pace, Maria Carmela; Cozzolino, Flora; Monti, Maria; Milella, Luigi; Carmosino, Monica; Pucci, Piero; Bisaccia, Faustino

2018-04-28

Up-regulated Gene clone 7 (URG7) is an ER resident protein, whose expression is up-regulated in the presence of hepatitis B virus X antigen (HBxAg) during HBV infection. In virus-infected hepatocytes, URG7 shows an anti-apoptotic activity due to the PI3K/AKT signalling activation, does not seem to have tumorigenic properties, but it appears to promote the development and progression of fibrosis. However, the molecular mechanisms underlying URG7 activity remain largely unknown. To shed light on URG7 activity, we first analysed its interactome in HepG2 transfected cells: this analysis suggests that URG7 could have a role in affecting protein synthesis, folding and promoting proteins degradation. Moreover, keeping into account its subcellular localisation in the ER and that several viral infections give rise to ER stress, a panel of experiments was performed to evaluate a putative role of URG7 in ER stress. Our main results demonstrate that in ER-stressed cells URG7 is able to modulate the expression of Unfolded Protein Response (UPR) markers towards survival outcomes, up-regulating GRP78 protein and down-regulating the pro-apoptotic protein CHOP. Furthermore, URG7 reduces the ER stress by decreasing the amount of unfolded proteins, by increasing both the total protein ubiquitination and the AKT activation and reducing Caspase 3 activation. All together these data suggest that URG7 plays a pivotal role as a reliever of ER stress-induced apoptosis. This is the first characterisation of URG7 activity under ER stress conditions. The results presented here will help to hypothesise new strategies to counteract the antiapoptotic activity of URG7 in the context of the viral infection. © 2018 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.