Probable essential thrombocythemia in a dog

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

Hopper, P.E.; Mandell, C.P.; Turrel, J.M.

1989-04-01

Essential thrombocythemia (ET), in an 11-year-old dog was characterized by persistently high platelet counts range, 4.19 X 10(6)/microliters to 4.95 X 10(6)/microliters, abnormal platelet morphology, marked megakaryocytic hyperplasia in the bone marrow, absence of circulating megakaryoblasts, and history of splenomegaly and gastrointestinal bleeding. Increased numbers of megakaryocytes and megakaryoblasts (15% to 20%) in the bone marrow were confirmed by a positive acetylcholinesterase reaction. Another significant finding was the presence of a basophilia in blood (4,836/microliters) and bone marrow. The marked persistent thrombocytosis, absence of reactive (secondary) thrombocytosis, abnormal platelet morphology, and quantitative and qualitative changes in the megakaryocytic series inmore » the bone marrow suggested the presence of a myeloproliferative disease. Cytochemical and ultrastructural findings aided in the diagnosis of ET. The dog was treated with radiophosphorus. The results was a rapid decline in the numbers of megakaryoblasts and megakaryocytes in the bone marrow and platelets and basophils in the peripheral blood. The dog died unexpectedly of acute necrotizing pancreatitis and diabetes mellitus before a complete remission was achieved.« less

Mutant calreticulin knockin mice develop thrombocytosis and myelofibrosis without a stem cell self-renewal advantage.

PubMed

Li, Juan; Prins, Daniel; Park, Hyun Jung; Grinfeld, Jacob; Gonzalez-Arias, Carlos; Loughran, Stephen; Dovey, Oliver M; Klampfl, Thorsten; Bennett, Cavan; Hamilton, Tina L; Pask, Dean C; Sneade, Rachel; Williams, Matthew; Aungier, Juliet; Ghevaert, Cedric; Vassiliou, George S; Kent, David G; Green, Anthony R

2018-02-08

Somatic mutations in the endoplasmic reticulum chaperone calreticulin (CALR) are detected in approximately 40% of patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF). Multiple different mutations have been reported, but all result in a +1-bp frameshift and generate a novel protein C terminus. In this study, we generated a conditional mouse knockin model of the most common CALR mutation, a 52-bp deletion. The mutant novel human C-terminal sequence is integrated into the otherwise intact mouse CALR gene and results in mutant CALR expression under the control of the endogenous mouse locus. CALR del/+ mice develop a transplantable ET-like disease with marked thrombocytosis, which is associated with increased and morphologically abnormal megakaryocytes and increased numbers of phenotypically defined hematopoietic stem cells (HSCs). Homozygous CALR del/del mice developed extreme thrombocytosis accompanied by features of MF, including leukocytosis, reduced hematocrit, splenomegaly, and increased bone marrow reticulin. CALR del/+ HSCs were more proliferative in vitro, but neither CALR del/+ nor CALR del/del displayed a competitive transplantation advantage in primary or secondary recipient mice. These results demonstrate the consequences of heterozygous and homozygous CALR mutations and provide a powerful model for dissecting the pathogenesis of CALR-mutant ET and PMF. © 2018 by The American Society of Hematology.

Thrombocytosis: a retrospective study of 165 dogs.

PubMed

Neel, Jennifer A; Snyder, Laura; Grindem, Carol B

2012-06-01

Thrombocytosis has been associated with various conditions, including inflammation, neoplasia, iron deficiency, splenectomy, and drug administration. The aim of this study was to characterize diseases and conditions associated with thrombocytosis in dogs. In this retrospective study, dogs with thrombocytosis (platelet count > 600 × 10(3) /μL) and complete medical records during a 1-year period were included, and breed, sex, age, CBC results, alkaline phosphatase and gamma-glutamyltransferase activities in some dogs, administration of glucocorticoids or vincristine, and primary diagnosis were evaluated. Thrombocytosis was found in 240 of 5342 dogs (4.6%), and 165 (3.1%) met inclusion criteria. Thrombocytosis was secondary in all dogs, and underlying diseases and conditions (n,%) were neoplasia (56, 33.9%), inflammation (55, 33.3%), miscellaneous disorders (26, 15.8%), neoplasia plus a second disease (13, 7.9%), endocrine diseases (8, 4.8%), and multiple diseases (7, 4.2%). In dogs with neoplasia, carcinomas (24) and round cell neoplasms (20), especially lymphoma and mast cell tumor, were the most frequent tumors. Inflammatory disorders consisted of immune-mediated disorders (11), neurologic diseases (8), infectious diseases (6), allergic disease (5), orthopedic diseases (4), gastrointestinal diseases (4), and miscellaneous conditions (17). Of the 165 dogs, 73 (44.2%) had received glucocorticoids (55) or vincristine (18) Marked (850-969 × 10(3) platelets/μL) or extreme ( ≥ 970 × 10(3) platelets/μL) thrombocytosis occurred in 24 (14.5%) dogs; 12 (50.0%) had neoplasia. Thromboembolism occurred in 13 (7.9%) dogs. Thrombocytosis in dogs occurred most frequently secondary to neoplastic and inflammatory diseases and was commonly associated with glucocorticoid and vincristine administration. Thromboembolic complications occurred in a small number of patients. Marked or extreme thrombocytosis was more likely to occur with neoplasia than with other conditions. © 2012 American Society for Veterinary Clinical Pathology.

Molecular Basis of Essential Thrombocytosis

DTIC Science & Technology

2008-06-01

Membrane proteins,” below), and 64% were present in the cytoskeleton, endoplasmic reticulum, mitochondria, cytosol, or Golgi apparatus ... perspectives Future advances in proteomic technology that incorporate miniatur- ization,101 coupled with an ability to integrate functional genomics...14. Kralovics R, Passamonti F, Buser AS, et al. A gain-of- function mutation of JAK2 in myeloproliferative disorders. The New England Journal of

Magnitude of reactive thrombocytosis and associated clinical conditions in dogs.

PubMed

Athanasiou, Labrini V; Polizopoulou, Zoe S; Papavasileiou, Eleftheria G; Mpairamoglou, Efstathios L; Kantere, Maria C; Rousou, Xanthi A

2017-09-09

Previous studies on the underlying causes of thrombocytosis have raised scientific interest in its clinical relevance in dogs. The purpose of this study was: (1) to explore the clinical conditions associated with thrombocytosis; (2) to compare platelet counts among these conditions; and (3) to identify possible interactions with other haematological variables and associated conditions. Medical records of 195 dogs with thrombocytosis (platelet count >500×10 3 /μL) were reviewed for signalment, complete blood count results and definitive diagnosis. The prevalence of thrombocytosis was 6.02%. All cases included had reactive thrombocytosis, with non-neoplastic, non-inflammatory underlying conditions in 48.2%, inflammatory processes in 34.4% and neoplastic processes in 17.4%. Haemoglobin and white blood cell counts were negatively and positively associated with platelet count, respectively. This study revealed that mean platelet count in dogs with neoplasia and a packed cell volume of 35% or below was significantly higher than that for dogs with other disease categories. Therefore, for dogs with marked thrombocytosis and anaemia, it is recommended that neoplasia should be included in the list of differential diagnoses. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Thrombocytosis in systemic lupus erythematosus: a possible clue to autosplenectomy?

PubMed

Castellino, Gabriella; Govoni, Marcello; Prandini, Napoleone; Limpido, Gessica; Bernardi, Simone; Campione, Diana; Lanza, Francesco; Trotta, Francesco

2007-07-01

Thrombocytosis can be due to a myeloproliferative disorder or to a reactive or secondary process; among these are connective tissue disorders, in particular systemic lupus erythematosus (SLE). Besides being an expression of active disease, this unusual finding has also been described in SLE complicated by autosplenectomy. We evaluated the prevalence of thrombocytosis in a series of SLE patients and its relationship to functional asplenia. Platelet count was evaluated in 465 consecutive Caucasian patients with SLE (387 women, 78 men, median age 54 yrs). Thrombocytosis was defined as platelet count > 400 x 10(9)/l in at least 3 blood samples. All patients with thrombocytosis underwent peripheral blood smears for erythrocyte abnormalities and instrumental spleen evaluation. Seventeen patients (3.7%) with thrombocytosis were observed. Peripheral blood smear showed Howell-Jolly bodies, spherocytes, and target cells in 3/17 patients (17.6%). In the same 3 patients, ultrasound and computed tomography failed to evidence the spleen, and liver-spleen scans showed absence of splenic uptake (a finding indicative of functional autosplenectomy). One satisfied criteria for antiphospholipid syndrome (APS), and the other 2 patients had positive IgG antiphospholipid antibodies (aPL) at medium titer. The sudden appearance and persistence of thrombocytosis or even the apparent reversal of thrombocytopenia in patients with SLE should raise suspicion of autosplenectomy, in particular if secondary APS or aPL is present.

Successful replantation of 2 digits in a patient with thrombocytosis after splenectomy: A case report.

PubMed

Hwang, Jae Ha; Kim, Dong Wan; Kim, Kwang Seog; Lee, Sam Yong

2018-06-01

Thrombosis is the most common complication of thrombocytosis, which can be particularly damaging to reattached digits. We present a guideline about digital replantation when thrombocytosis is expected. We report a case of an 18-year-old man who sustained a traumatic amputation of two fingers and splenic rupture in a traffic accident. He underwent digital replantation the day after splenectomy when life-threatening conditions had been managed. The platelet count increased to over 1,300,000/mm and post-splenectomy reactive thrombocytosis was diagnosed. Hydroxyurea and anagrelide were administered to control the platelet count after consultation with a hematologist. The reattached fingers survived without any complication. In patients with digital amputation, replantation can be attempted, even when thrombocytosis is expected, when requested by the patient. Furthermore, the platelet count should be actively controlled with medication to improve the survival rate of the reattached finger.

Mpl expression on megakaryocytes and platelets is dispensable for thrombopoiesis but essential to prevent myeloproliferation

PubMed Central

Ng, Ashley P.; Kauppi, Maria; Metcalf, Donald; Hyland, Craig D.; Josefsson, Emma C.; Lebois, Marion; Zhang, Jian-Guo; Baldwin, Tracey M.; Di Rago, Ladina; Hilton, Douglas J.; Alexander, Warren S.

2014-01-01

Thrombopoietin (TPO) acting via its receptor, the cellular homologue of the myeloproliferative leukemia virus oncogene (Mpl), is the major cytokine regulator of platelet number. To precisely define the role of specific hematopoietic cells in TPO-dependent hematopoiesis, we generated mice that express the Mpl receptor normally on stem/progenitor cells but lack expression on megakaryocytes and platelets (MplPF4cre/PF4cre). MplPF4cre/PF4cre mice displayed profound megakaryocytosis and thrombocytosis with a remarkable expansion of megakaryocyte-committed and multipotential progenitor cells, the latter displaying biological responses and a gene expression signature indicative of chronic TPO overstimulation as the underlying causative mechanism, despite a normal circulating TPO level. Thus, TPO signaling in megakaryocytes is dispensable for platelet production; its key role in control of platelet number is via generation and stimulation of the bipotential megakaryocyte precursors. Nevertheless, Mpl expression on megakaryocytes and platelets is essential to prevent megakaryocytosis and myeloproliferation by restricting the amount of TPO available to stimulate the production of megakaryocytes from the progenitor cell pool. PMID:24711413

Mpl expression on megakaryocytes and platelets is dispensable for thrombopoiesis but essential to prevent myeloproliferation.

PubMed

Ng, Ashley P; Kauppi, Maria; Metcalf, Donald; Hyland, Craig D; Josefsson, Emma C; Lebois, Marion; Zhang, Jian-Guo; Baldwin, Tracey M; Di Rago, Ladina; Hilton, Douglas J; Alexander, Warren S

2014-04-22

Thrombopoietin (TPO) acting via its receptor, the cellular homologue of the myeloproliferative leukemia virus oncogene (Mpl), is the major cytokine regulator of platelet number. To precisely define the role of specific hematopoietic cells in TPO-dependent hematopoiesis, we generated mice that express the Mpl receptor normally on stem/progenitor cells but lack expression on megakaryocytes and platelets (Mpl(PF4cre/PF4cre)). Mpl(PF4cre/PF4cre) mice displayed profound megakaryocytosis and thrombocytosis with a remarkable expansion of megakaryocyte-committed and multipotential progenitor cells, the latter displaying biological responses and a gene expression signature indicative of chronic TPO overstimulation as the underlying causative mechanism, despite a normal circulating TPO level. Thus, TPO signaling in megakaryocytes is dispensable for platelet production; its key role in control of platelet number is via generation and stimulation of the bipotential megakaryocyte precursors. Nevertheless, Mpl expression on megakaryocytes and platelets is essential to prevent megakaryocytosis and myeloproliferation by restricting the amount of TPO available to stimulate the production of megakaryocytes from the progenitor cell pool.

Mutant calreticulin-expressing cells induce monocyte hyperreactivity through a paracrine mechanism

PubMed Central

Garbati, Michael R.; Welgan, Catherine A.; Landefeld, Sally H.; Newell, Laura F.; Agarwal, Anupriya; Dunlap, Jennifer B.; Chourasia, Tapan K.; Lee, Hyunjung; Elferich, Johannes; Traer, Elie; Rattray, Rogan; Cascio, Michael J.; Press, Richard D.; Bagby, Grover C.; Tyner, Jeffrey W.; Druker, Brian J.; Dao, Kim-Hien T.

2016-01-01

Mutations in the calreticulin gene (CALR) were recently identified in approximately 70–80% of patients with JAK2-V617F-negative essential thrombocytosis and primary myelofibrosis. All frameshift mutations generate a recurring novel C-terminus. Here we provide evidence that mutant calreticulin does not accumulate efficiently in cells and is abnormally enriched in the nucleus and extracellular space compared to wildtype calreticulin. The main determinant of these findings is the loss of the calcium-binding and KDEL domains. Expression of type I mutant CALR in Ba/F3 cells confers minimal IL-3-independent growth. Interestingly, expression of type I and type II mutant CALR in a non-hematopoietic cell line does not directly activate JAK/STAT signaling compared to JAK2-V617F expression. These results led us to investigate paracrine mechanisms of JAK/STAT activation. Here we show that conditioned media from cells expressing type I mutant CALR exaggerate cytokine production from normal monocytes with or without treatment with a toll-like receptor agonist. These effects are not dependent on the novel C-terminus. These studies offer novel insights into the mechanism of JAK/STAT activation in patients with JAK2-V617F-negative essential thrombocytosis and primary myelofibrosis. PMID:26573090

Primary thrombocytosis in children

PubMed Central

Kucine, Nicole; Chastain, Katherine M.; Mahler, Michelle B.; Bussel, James B.

2014-01-01

Myeloproliferative neoplasms are uncommon disorders in children, for which we have limited understanding of the pathogenesis and optimal management. JAK2 and MPL mutations, while common drivers of myeloproliferative neoplasms in adult patients, are not clearly linked to pediatric disease. Management and clinical outcomes in adults have been well delineated with defined recommendations for risk stratification and treatment. This is not the case for pediatric patients, for whom there is neither a standard approach to workup nor any consensus regarding management. This review will discuss thrombocytosis in children, including causes of thrombocytosis in children, the limited knowledge we have regarding pediatric primary thrombocytosis, and our thoughts on potential risk stratification and management, and future questions to be answered by laboratory research and collaborative clinical study. PMID:24688110

Philadelphia-negative chronic myeloproliferative neoplasms

PubMed Central

Bittencourt, Rosane Isabel; Vassallo, Jose; Chauffaille, Maria de Lourdes Lopes Ferrari; Xavier, Sandra Guerra; Pagnano, Katia Borgia; Nascimento, Ana Clara Kneese; De Souza, Carmino Antonio; Chiattone, Carlos Sergio

2012-01-01

Chronic myeloproliferative diseases without the Philadelphia chromosome marker (Ph-), although first described 60 years ago, only became the subject of interest after the turn of the millennium. In 2001, the World Health Organization (WHO) defined the classification of this group of diseases and in 2008 they were renamed myeloproliferative neoplasms based on morphological, cytogenetic and molecular features. In 2005, the identification of a recurrent molecular abnormality characterized by a gain of function with a mutation in the gene encoding Janus kinase 2 (JAK2) paved the way for greater knowledge of the pathophysiology of myeloproliferative neoplasms. The JAK2 mutation is found in 90-98% of polycythemia vera and in about 50% essential thrombocytosis and primary myelofibrosis. In addition to the JAK2 mutation, other mutations involving TET2 (ten-eleven translocation), LNK (a membrane-bound adaptor protein); IDH1/2 (isocitrate dehydrogenase 1/2 enzyme); ASXL1 (additional sex combs-like 1) genes were found in myeloproliferative neoplasms thus showing the importance of identifying molecular genetic alterations to confirm diagnosis, guide treatment and improve our understanding of the biology of these diseases. Currently, polycythemia vera, essential thrombocytosis, myelofibrosis, chronic neutrophilic leukemia, chronic eosinophilic leukemia and mastocytosis are included in this group of myeloproliferative neoplasms, but are considered different situations with individualized diagnostic methods and treatment. This review updates pathogenic aspects, molecular genetic alterations, the fundamental criteria for diagnosis and the best approach for each of these entities. PMID:23049404

Cholesterol efflux in megakaryocyte progenitors suppresses platelet production and thrombocytosis

PubMed Central

Murphy, Andrew J.; Bijl, Nora; Yvan-Charvet, Laurent; Welch, Carrie B.; Bhagwat, Neha; Reheman, Adili; Wang, Yiming; Shaw, James A.; Levine, Ross L.; Ni, Heyu; Tall, Alan R.; Wang, Nan

2013-01-01

Platelets play a key role in atherogenesis and its complications. Both hypercholesterolemia and increased platelet production promote athero-thrombosis; however, a potential link between altered cholesterol homeostasis and platelet production has not been explored. Transplantation of bone marrow (BM) deficient in ABCG4, a transporter of unknown function, into Ldlr−/− mice resulted in thrombocytosis, accelerated thrombosis and atherosclerosis. While not detected in lesions, Abcg4 was highly expressed in BM megakaryocyte progenitors (MkP). Abcg4−/− MkPs displayed defective cholesterol efflux to HDL, increased cell surface levels of thrombopoietin (TPO) receptor (c-MPL) and enhanced proliferation. This appeared to reflect disruption of the negative feedback regulation of c-MPL levels and signaling by E3 ligase c-CBL and cholesterol-sensing LYN kinase. HDL infusions reduced platelet counts in Ldlr−/− mice and in a mouse model of myeloproliferative neoplasm, in a completely ABCG4-dependent fashion. HDL infusions may offer a novel approach to reducing athero-thrombotic events associated with increased platelet production. PMID:23584088

Identification of MPL R102P Mutation in Hereditary Thrombocytosis.

PubMed

Bellanné-Chantelot, Christine; Mosca, Matthieu; Marty, Caroline; Favier, Rémi; Vainchenker, William; Plo, Isabelle

2017-01-01

The molecular basis of hereditary thrombocytosis is germline mutations affecting the thrombopoietin (TPO)/TPO receptor (MPL)/JAK2 signaling axis. Here, we report one family presenting two cases with a mild thrombocytosis. By sequencing JAK2 and MPL coding exons, we identified a germline MPL R102P heterozygous mutation in the proband and his daughter. Concomitantly, we detected high TPO levels in the serum of these two patients. The mutation was not found in three other unaffected cases from the family except in another proband's daughter who did not present thrombocytosis but had a high TPO level. The MPL R102P mutation was first described in congenital amegakaryocytic thrombocytopenia in a homozygous state with a loss-of-function activity. It was previously shown that MPL R102P was blocked in the endoplasmic reticulum without being able to translocate to the plasma membrane. Thus, this case report identifies for the first time that MPL R102P mutation can differently impact megakaryopoiesis: thrombocytosis or thrombocytopenia depending on the presence of the heterozygous or homozygous state, respectively. The paradoxical effect associated with heterozygous MPL R102P may be due to subnormal cell-surface expression of wild-type MPL in platelets inducing a defective TPO clearance. As a consequence, increased TPO levels may activate megakaryocyte progenitors that express a lower, but still sufficient level of MPL for the induction of proliferation.

Cyclical thrombocytosis, acquired von Willebrand syndrome and aggressive non-melanoma skin cancers are common in patients with Philadelphia-negative myeloproliferative neoplasms treated with hydroxyurea.

PubMed

Verner, Emma; Forsyth, Cecily; Grigg, Andrew

2014-05-01

Abstract Cyclical thrombocytosis, acquired von Willebrand syndrome, aggressive non-melanoma skin cancers and other hydroxyurea complications have been reported in Philadelphia-negative myeloproliferative neoplasms (MPNs), but their incidence and clinical consequences have not been defined in a large cohort of patients. We conducted a retrospective analysis of 188 consecutive patients with MPNs specifically addressing the incidence of these complications. Cyclical thrombocytosis was documented in 29 patients (15%), the majority of whom were receiving hydroxyurea. Acquired von Willebrand syndrome was identified in 17 of the 84 screened patients (20%), but was not associated with any major bleeding complications. Non-melanoma skin cancers were reported in 51 patients (27%). Hydroxyurea-related fever occurred in nine of 149 patients (6%) who received hydroxyurea. Seventy-three patients (39%) experienced a total of 98 major thrombotic events, with the majority of these occurring prior to or within 3 months of the diagnosis. Cyclical thrombocytosis, acquired von Willebrand syndrome, aggressive non-melanoma skin cancers and other hydroxyurea-related complications are not infrequent in MPNs and have important clinical consequences for management.

Iron deficiency alters megakaryopoiesis and platelet phenotype independent of thrombopoietin.

PubMed

Evstatiev, Rayko; Bukaty, Adam; Jimenez, Kristine; Kulnigg-Dabsch, Stefanie; Surman, Lidia; Schmid, Werner; Eferl, Robert; Lippert, Kathrin; Scheiber-Mojdehkar, Barbara; Kvasnicka, Hans Michael; Khare, Vineeta; Gasche, Christoph

2014-05-01

Iron deficiency is a common cause of reactive thrombocytosis, however, the exact pathways have not been revealed. Here we aimed to study the mechanisms behind iron deficiency-induced thrombocytosis. Within few weeks, iron-depleted diet caused iron deficiency in young Sprague-Dawley rats, as reflected by a drop in hemoglobin, mean corpuscular volume, hepatic iron content and hepcidin mRNA in the liver. Thrombocytosis established in parallel. Moreover, platelets produced in iron deficient animals displayed a higher mean platelet volume and increased aggregation. Bone marrow studies revealed subtle alterations that are suggestive of expansion of megakaryocyte progenitors, an increase in megakaryocyte ploidy and accelerated megakaryocyte differentiation. Iron deficiency did not alter the production of hematopoietic growth factors such as thrombopoietin, interleukin 6 or interleukin 11. Megakaryocytic cell lines grown in iron-depleted conditions exhibited reduced proliferation but increased ploidy and cell size. Our data suggest that iron deficiency increases megakaryopoietic differentiation and alters platelet phenotype without changes in megakaryocyte growth factors, specifically TPO. Iron deficiency-induced thrombocytosis may have evolved to maintain or increase the coagulation capacity in conditions with chronic bleeding. Copyright © 2014 Wiley Periodicals, Inc.

Thrombocytosis is associated with increased short and long term mortality after exacerbation of chronic obstructive pulmonary disease: a role for antiplatelet therapy?

PubMed

Harrison, Michelle T; Short, Philip; Williamson, Peter A; Singanayagam, Aran; Chalmers, James D; Schembri, Stuart

2014-07-01

Evidence suggests that platelets play a significant role in inflammation in addition to their role in thrombosis. Systemic inflammation is linked to poor short and long term outcomes in COPD. Increased platelet activation has been reported in acute exacerbations of COPD (AECOPD). We investigated whether thrombocytosis is independently associated with poor outcomes following AECOPD. An observational cohort study of patients hospitalised with AECOPD was performed. Patients were >40 years with spirometry confirmed COPD admitted between 2009 and 2011. Platelet count was recorded on admission. The primary outcome was 1-year all-cause mortality. Secondary outcomes included inhospital mortality and cardiovascular events. Analyses were conducted using logistic regression after adjustment for confounding variables. 1343 patients (49% male) were included. Median age was 72 years (IQR 63-79 years). 157 (11.7%) had thrombocytosis. Thrombocytosis was associated with both 1-year mortality and inhospital mortality; OR 1.53 (95% CI 1.03 to 2.29, p=0.030) and OR 2.37 (95% CI 1.29 to 4.34, p=0.005), respectively. Cardiovascular hospitalisation was not significantly increased (OR 1.13 (95% CI 0.73 to 1.76, p=0.600)) in patients with thrombocytosis. Aspirin or clopidogrel treatment correlated with a reduction in 1-year mortality (OR 0.63 (95% CI 0.47 to 0.85, p=0.003)) but not inhospital mortality (OR 0.69 (95% CI 0.41 to 1.11, p=0.124)). After adjustment for confounders thrombocytosis was associated with increased 1-year mortality after exacerbation of COPD. Antiplatelet therapy was associated with significantly lower 1-year mortality and may have a protective role to play in patients with AECOPD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Thrombocytosis distinguishes POEMS syndrome from chronic inflammatory demyelinating polyneuropathy.

PubMed

Naddaf, Elie; Dispenzieri, Angela; Mandrekar, Jay; Mauermann, Michelle L

2015-10-01

POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, and skin changes) syndrome may be mistaken for chronic inflammatory demyelinating polyneuropathy (CIDP). Differentiating the 2 entities is crucial, as there are major treatment implications. We compared platelet counts in 136 POEMS patients and 67 CIDP controls. Of the patients with POEMS, 53.7% had thrombocytosis, compared with 1.5% of those with CIDP (P < 0.0001). The median platelet count in patients with POEMS was 467,000/μl compared with 275,000/μl in those with CIDP (P < 0.0001). Thrombocytosis is a helpful indicator to prompt clinicians to consider the diagnosis of POEMS syndrome in patients who are thought to have CIDP, and is an important reminder of the increased risk of thrombotic events in POEMS syndrome. © 2015 Wiley Periodicals, Inc.

Thrombocytosis in a male patient with acute promyelocytic leukaemia during all-trans retinoic (ATRA) acid treatment.

PubMed

Aldapt, Mohmood B; Kassem, Nancy; Al-Okka, Randa; Ghasoub, Rula; Soliman, Dina; Abdulla, Mohammad A; Mudawi, Deena; Ibrahim, Feryal; Yassin, Mohamed A

2018-04-03

We present a rather uncommon side effect observed in a 20-year-old man with acute promyelocytic leukemia during treatment with ATRA. He developed a high platelet counts reaching up to 1655×10⁹/L on day 29 of ATRA treatment, and started to recover spontaneously on day 33 of treatment, without any change in ATRA, or adding any cytoreduction therapy. No complications associated with thrombocytosis were observed. IL-6 seems to play an important role in the pathogenesis of the thrombocytosis induced by ATRA. However, it is unclear what are the precipitating factors for this rare phenomenon and whether it is caused by certain predisposing factors that might be related to patient's, disease pathogenesis or other unknown factors.

Refractory Anemia with Ring Sideroblasts (RARS) and RARS with Thrombocytosis (RARS-T) – “2017 Update on Diagnosis, Risk-stratification, and Management”

PubMed Central

Patnaik, Mrinal M.; Tefferi, Ayalew

2017-01-01

Disease Overview Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS), now classified under myelodysplastic syndromes with RS (MDS-RS) and RARS with thrombocytosis (RARS-T); now called myelodysplastic/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T). Diagnosis MDS-RS is a lower risk MDS, with single or multilineage dysplasia (SLD/MLD), <5% bone marrow (BM) blasts and ≥15% BM RS (≥5% in the presence of SF3B1 mutations). MDS/MPN-RS-T, now a formal entity in the MDS/MPN overlap syndromes, has diagnostic features of MDS-RS-SLD, along with a platelet count ≥ 450 × 10(9)/L and large atypical megakaryocytes (similar to BCR-ABL1 negative MPN). Mutations and Karyotype Mutations in SF3B1 are seen in ≥80% of patients with MDS-RS-SLD and MDS/MPN-RS-T, and strongly correlate with the presence of BM RS; MDS/MPN-RS-T patients also demonstrate JAK2V617F, ASXL1, DNMT3A, SETBP1, and TET2 mutations; with ASXL1/SETBP1 mutations adversely impacting survival. Cytogenetic abnormalities are uncommon in both diseases. Risk stratification Most patients with MDS-RS-SLD are stratified into lower risk groups by the revised-International Prognostic Scoring System (R-IPSS). Disease outcome in MDS/MPN-RS-T is better than that of MDS-RS-SLD, but worse than that of essential thrombocythemia. Both diseases have a low risk of leukemic transformation. Treatment Anemia and iron overload are complications seen in both and are managed similar to lower risk MDS and MPN. Aspirin therapy is reasonable in MDS/MPN-RS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs is uncertain. PMID:28188970

Expression of CALR mutants causes mpl-dependent thrombocytosis in zebrafish.

PubMed

Lim, K-H; Chang, Y-C; Chiang, Y-H; Lin, H-C; Chang, C-Y; Lin, C-S; Huang, L; Wang, W-T; Gon-Shen Chen, C; Chou, W-C; Kuo, Y-Y

2016-10-07

CALR mutations are identified in about 30% of JAK2/MPL-unmutated myeloproliferative neoplasms (MPNs) including essential thrombocythemia (ET) and primary myelofibrosis. Although the molecular pathogenesis of CALR mutations leading to MPNs has been studied using in vitro cell lines models, how mutant CALR may affect developmental hematopoiesis remains unknown. Here we took advantage of the zebrafish model to examine the effects of mutant CALR on early hematopoiesis and model human CALR-mutated MPNs. We identified three zebrafish genes orthologous to human CALR, referred to as calr, calr3a and calr3b. The expression of CALR-del52 and CALR-ins5 mutants caused an increase in the hematopoietic stem/progenitor cells followed by thrombocytosis without affecting normal angiogenesis. The expression of CALR mutants also perturbed early developmental hematopoiesis in zebrafish. Importantly, morpholino knockdown of mpl but not epor or csf3r could significantly attenuate the effects of mutant CALR. Furthermore, the expression of mutant CALR caused jak-stat signaling activation in zebrafish that could be blocked by JAK inhibitors (ruxolitinib and fedratinib). These findings showed that mutant CALR activates jak-stat signaling through an mpl-dependent mechanism to mediate pathogenic thrombopoiesis in zebrafish, and illustrated that the signaling machinery related to mutant CALR tumorigenesis are conserved between human and zebrafish.

Leucocytosis, Thrombocytosis, and Plasma Osmolality During Rest and Exercise: A Hypothesis

NASA Technical Reports Server (NTRS)

McKenzie, M. A.; Greenleaf, John E.; Looft-Wilson, R.; Barnes, P. R.

1999-01-01

The mechanism for inducing leucocytosis (increase in white blood cells) and thrombocytosis (increase in platelets) during exercise is unclear. Because plasma osmolality (Osm) may influence T-cell proliferation, Osm and the number of leucocytes (WBC) and platelets in blood were measured periodically during a 90 min rest period, and were compared with those during upright sitting ergometer exercise in six unt.rained, healthy men who cycled for 70 min at 71% of their maximal oxygen uptake (V prime O(sub 2(sub max)). There were 6 experiments in which the subjects drank different fluid formula-t4ilons (10 ml/kg) of various ionic and osmotic concentrations intermittently during 60 min of the rest period and during the exercise period. Osmolality, and WBC and platelet counts increased significantly (p<0.05) within the first 10 min of exercise, but the additional 60 min of exercise did not significantly change the leucocytosis or thrombocytosis. There were low but significant correlations between individual values of total WBC and total Osm during exercise (r(sub 0.001(2),284) = 0.39) and during rest plus exercise (r(sub 0.001(2),499) = 0.43). With combined data from the six experiments, mean Osm correlated highly and significantly with both mean WBC (r(sub 0.001(2),6) = 0.95, p < 0.001) and mean platelets (r(sub 0.001(2),6) = 0.94, p < 0.01) during the exercise phase. These data indicate that increases in leucocytes, thrombocytes, and osmolality occur primarily within the first 10 min of high-intensity exercise, but neither hypovolemia nor hyperthermia during exercise contributed to the leucocytosis, thrombocytosis, or hyperosmolality. The high correlations between plasma Osm and WBC or platelet counts suggest changes in osmolality may contribute to the mechanism of leucocytosis and thrombocytosis induced by exercise.

Carotid Artery Stiffness, Digital Endothelial Function, and Coronary Calcium in Patients with Essential Thrombocytosis, Free of Overt Atherosclerotic Disease

PubMed Central

Vrtovec, Matjaz; Anzic, Ajda; Zupan, Irena Preloznik; Zaletel, Katja

2017-01-01

Abstract Background Patients with myeloproliferative neoplasms (MPNs) are at increased risk for atherothrombotic events. Our aim was to determine if patients with essential thrombocytosis (ET), a subtype of MPNs, free of symptomatic atherosclerosis, have greater carotid artery stiffness, worse endothelial function, greater coronary calcium and carotid plaque burden than control subjects. Patients and methods 40 ET patients without overt vascular disease, and 42 apparently healthy, age and sex-matched control subjects with comparable classical risk factors for atherosclerosis and Framingham risk of coronary disease were enrolled. All subjects were examined by physical and laboratory testing, carotid echo-tracking ultrasound, digital EndoPat pletysmography and CT coronary calcium scoring. Results No significant differences were found between ET patients and controls in carotid plaque score [1 (0-1.25) vs. 0 (0-2), p=0.30], β- index of carotid stiffness [7.75 (2.33) vs. 8.44 (2,81), p=0.23], pulse wave velocity [6,21 (1,00) vs. 6.45 (1.04) m/s; p=0.46], digital reactive hyperemia index [2.10 (0.57) vs. 2.35 (0.62), p=0.07], or augmentation index [19 (3-30) vs. 13 (5-22) %, p=0.38]. Overall coronary calcium burden did not differ between groups [Agatston score 0.1 (0-16.85) vs. 0 (0-8.55), p=0.26]. However, significantly more ET patients had an elevated coronary calcium score of >160 [6/40 vs. 0/42, p < 0.01]. Conclusions No significant differences between groups were found in carotid artery morphology and function, digital endothelial function or overall coronary calcium score. Significantly more ET patients had an elevated coronary calcium score of >160, indicating high cardiovascular risk, not predicted by the Framingham equation. PMID:28740456

Carotid Artery Stiffness, Digital Endothelial Function, and Coronary Calcium in Patients with Essential Thrombocytosis, Free of Overt Atherosclerotic Disease.

PubMed

Vrtovec, Matjaz; Anzic, Ajda; Zupan, Irena Preloznik; Zaletel, Katja; Blinc, Ales

2017-06-01

Patients with myeloproliferative neoplasms (MPNs) are at increased risk for atherothrombotic events. Our aim was to determine if patients with essential thrombocytosis (ET), a subtype of MPNs, free of symptomatic atherosclerosis, have greater carotid artery stiffness, worse endothelial function, greater coronary calcium and carotid plaque burden than control subjects. 40 ET patients without overt vascular disease, and 42 apparently healthy, age and sex-matched control subjects with comparable classical risk factors for atherosclerosis and Framingham risk of coronary disease were enrolled. All subjects were examined by physical and laboratory testing, carotid echo-tracking ultrasound, digital EndoPat pletysmography and CT coronary calcium scoring. No significant differences were found between ET patients and controls in carotid plaque score [1 (0-1.25) vs. 0 (0-2), p=0.30], β- index of carotid stiffness [7.75 (2.33) vs. 8.44 (2,81), p=0.23], pulse wave velocity [6,21 (1,00) vs. 6.45 (1.04) m/s; p=0.46], digital reactive hyperemia index [2.10 (0.57) vs. 2.35 (0.62), p=0.07], or augmentation index [19 (3-30) vs. 13 (5-22) %, p=0.38]. Overall coronary calcium burden did not differ between groups [Agatston score 0.1 (0-16.85) vs. 0 (0-8.55), p=0.26]. However, significantly more ET patients had an elevated coronary calcium score of >160 [6/40 vs. 0/42, p < 0.01]. No significant differences between groups were found in carotid artery morphology and function, digital endothelial function or overall coronary calcium score. Significantly more ET patients had an elevated coronary calcium score of >160, indicating high cardiovascular risk, not predicted by the Framingham equation.

The Small Molecule Inhibitor G6 Significantly Reduces Bone Marrow Fibrosis and the Mutant Burden in a Mouse Model of Jak2-Mediated Myelofibrosis

PubMed Central

Kirabo, Annet; Park, Sung O.; Wamsley, Heather L.; Gali, Meghanath; Baskin, Rebekah; Reinhard, Mary K.; Zhao, Zhizhuang J.; Bisht, Kirpal S.; Keserű, György M.; Cogle, Christopher R.; Sayeski, Peter P.

2013-01-01

Philadelphia chromosome–negative myeloproliferative neoplasms, including polycythemia vera, essential thrombocytosis, and myelofibrosis, are disorders characterized by abnormal hematopoiesis. Among these myeloproliferative neoplasms, myelofibrosis has the most unfavorable prognosis. Furthermore, currently available therapies for myelofibrosis have little to no efficacy in the bone marrow and hence, are palliative. We recently developed a Janus kinase 2 (Jak2) small molecule inhibitor called G6 and found that it exhibits marked efficacy in a xenograft model of Jak2-V617F–mediated hyperplasia and a transgenic mouse model of Jak2-V617F–mediated polycythemia vera/essential thrombocytosis. However, its efficacy in Jak2-mediated myelofibrosis has not previously been examined. Here, we hypothesized that G6 would be efficacious in Jak2-V617F–mediated myelofibrosis. To test this, mice expressing the human Jak2-V617F cDNA under the control of the vav promoter were administered G6 or vehicle control solution, and efficacy was determined by measuring parameters within the peripheral blood, liver, spleen, and bone marrow. We found that G6 significantly reduced extramedullary hematopoiesis in the liver and splenomegaly. In the bone marrow, G6 significantly reduced pathogenic Jak/STAT signaling by 53%, megakaryocytic hyperplasia by 70%, and the Jak2 mutant burden by 68%. Furthermore, G6 significantly improved the myeloid to erythroid ratio and significantly reversed the myelofibrosis. Collectively, these results indicate that G6 is efficacious in Jak2-V617F–mediated myelofibrosis, and given its bone marrow efficacy, it may alter the natural history of this disease. PMID:22796437

Erythropoietin, Iron Depletion and Relative Thrombocytosis: A Possible Explanation for Hemoglobin-Survival Paradox in Chronic Kidney Disease

PubMed Central

Streja, Elani; Kovesdy, Csaba P; Greenland, Sander; Kopple, Joel D.; McAllister, Charles J; Nissenson, Allen R; Kalantar-Zadeh, Kamyar

2017-01-01

Background High doses of human recombinant erythropoietin (rHuEPO) to achieve hemoglobin levels above 13 g/dL in chronic kidney disease appear associated with elevated mortality. Study Design We conducted logistic regression and survival analyses in a retrospective cohort of maintenance hemodialysis (MHD) patients to examine the hypothesis that the induced iron depletion with resultant relative thrombocytosis may be a possible contributor to the link between the high rHuEPO dose associated hemoglobin ≥13 g/dL and mortality. Setting & Participants The national database of a large dialysis organization (DaVita) with 40,787 MHD patients during July to December 2001 and their survival up to July 2004 were examined. Predictors Hemoglobin level, platelet count and administered rHuEPO dose during each calendar quarter. Outcomes & other Measurements Case-mix adjusted 3-year all-cause mortality; and measures of iron stores including serum ferritin and iron saturation ratio (ISAT). Results Higher platelet count was associated with lower iron stores and higher prescribed rHuEPO dose. Compared to hemoglobin of 12-13 g/dL, hemoglobin ≥13 g/dL was associated with increased mortality in the presence of relative thrombocytosis, i.e., platelet count ≥300,000/μl, (case-mix adjusted death-rate ratio [RR]: 1.21, 95% confidence limits [CL]: 1.02–1.44, P=0.03) as opposed to the absence of relative thrombocytosis (RR: 1.04, 95% CL: 0.98–1.08, P=0.13). Prescribed rHuEPO dose >20,000 units/week was associated with higher likelihood of iron depletion (ISAT<20%) and relative thrombocytosis (case-mix adjusted odds ratio: 2.53 [CL: 2.37–2.69] and 1.36 [CL: 1.30–1.42], respectively, p<0.001) and increased mortality over 3 years (death-rate ratio of 1.59, CL: 1.54, 1.65, p<0.001). Limitations Our results may incorporate uncontrolled confounding. Achieved hemoglobin may have different mortality-predictability than targeted hemoglobin. Conclusions Iron depletion and associated relative thrombocytosis might contribute to increased mortality when administering high rHuEPO doses to achieve hemoglobin ≥13 g/dL in MHD patients. Randomized trials are needed to test these observational associations. PMID:18760517

Glucose deprivation reversibly down-regulates tissue plasminogen activator via proteasomal degradation in rat primary astrocytes.

PubMed

Cho, Kyu Suk; Joo, So Hyun; Choi, Chang Soon; Kim, Ki Chan; Ko, Hyun Myung; Park, Jin Hee; Kim, Pitna; Hur, Jun; Lee, Sung Hoon; Bahn, Geon Ho; Ryu, Jong Hoon; Lee, Jongmin; Han, Seol-Heui; Kwon, Kyoung Ja; Shin, Chan Young

2013-05-20

Tissue plasminogen activator (tPA) is an essential neuromodulator whose involvement in multiple functions such as synaptic plasticity, cytokine-like immune function and regulation of cell survival mandates rapid and tight tPA regulation in the brain. We investigated the possibility that a transient metabolic challenge induced by glucose deprivation may affect tPA activity in rat primary astrocytes, the main cell type responsible for metabolic regulation in the CNS. Rat primary astrocytes were incubated in serum-free DMEM without glucose. Casein zymography was used to determine tPA activity, and tPA mRNA was measured by RT-PCR. The signaling pathways regulating tPA activity were identified by Western blotting. Glucose deprivation rapidly down-regulated the activity of tPA without affecting its mRNA level in rat primary astrocytes; this effect was mimicked by translational inhibitors. The down-regulation of tPA was accompanied by increased tPA degradation, which may be modulated by a proteasome-dependent degradation pathway. Glucose deprivation induced activation of PI3K-Akt-GSK3β, p38 and AMPK, and inhibition of these pathways using LY294002, SB203580 and compound C significantly inhibited glucose deprivation-induced tPA down-regulation, demonstrating the essential role of these pathways in tPA regulation in glucose-deprived astrocytes. Rapid and reversible regulation of tPA activity in rat primary astrocytes during metabolic crisis may minimize energy-requiring neurologic processes in stressed situations. This effect may thereby increase the opportunity to invest cellular resources in cell survival and may allow rapid re-establishment of normal cellular function after the crisis. Copyright © 2013 Elsevier Inc. All rights reserved.

MPLW515L Is a Novel Somatic Activating Mutation in Myelofibrosis with Myeloid Metaplasia

PubMed Central

Pikman, Yana; Lee, Benjamin H; Mercher, Thomas; McDowell, Elizabeth; Ebert, Benjamin L; Gozo, Maricel; Cuker, Adam; Wernig, Gerlinde; Moore, Sandra; Galinsky, Ilene; DeAngelo, Daniel J; Clark, Jennifer J; Lee, Stephanie J; Golub, Todd R; Wadleigh, Martha; Gilliland, D. Gary; Levine, Ross L

2006-01-01

Background The JAK2V617F allele has recently been identified in patients with polycythemia vera (PV), essential thrombocytosis (ET), and myelofibrosis with myeloid metaplasia (MF). Subsequent analysis has shown that constitutive activation of the JAK-STAT signal transduction pathway is an important pathogenetic event in these patients, and that enzymatic inhibition of JAK2V617F may be of therapeutic benefit in this context. However, a significant proportion of patients with ET or MF are JAK2V617F-negative. We hypothesized that activation of the JAK-STAT pathway might also occur as a consequence of activating mutations in certain hematopoietic-specific cytokine receptors, including the erythropoietin receptor (EPOR), the thrombopoietin receptor (MPL), or the granulocyte-colony stimulating factor receptor (GCSFR). Methods and Findings DNA sequence analysis of the exons encoding the transmembrane and juxtamembrane domains of EPOR, MPL, and GCSFR, and comparison with germline DNA derived from buccal swabs, identified a somatic activating mutation in the transmembrane domain of MPL (W515L) in 9% (4/45) of JAKV617F-negative MF. Expression of MPLW515L in 32D, UT7, or Ba/F3 cells conferred cytokine-independent growth and thrombopoietin hypersensitivity, and resulted in constitutive phosphorylation of JAK2, STAT3, STAT5, AKT, and ERK. Furthermore, a small molecule JAK kinase inhibitor inhibited MPLW515L-mediated proliferation and JAK-STAT signaling in vitro. In a murine bone marrow transplant assay, expression of MPLW515L, but not wild-type MPL, resulted in a fully penetrant myeloproliferative disorder characterized by marked thrombocytosis (Plt count 1.9–4.0 × 10 12/L), marked splenomegaly due to extramedullary hematopoiesis, and increased reticulin fibrosis. Conclusions Activation of JAK-STAT signaling via MPLW515L is an important pathogenetic event in patients with JAK2V617F-negative MF. The bone marrow transplant model of MPLW515L-mediated myeloproliferative disorders (MPD) exhibits certain features of human MF, including extramedullary hematopoiesis, splenomegaly, and megakaryocytic proliferation. Further analysis of positive and negative regulators of the JAK-STAT pathway is warranted in JAK2V617F-negative MPD. PMID:16834459

MPLW515L is a novel somatic activating mutation in myelofibrosis with myeloid metaplasia.

PubMed

Pikman, Yana; Lee, Benjamin H; Mercher, Thomas; McDowell, Elizabeth; Ebert, Benjamin L; Gozo, Maricel; Cuker, Adam; Wernig, Gerlinde; Moore, Sandra; Galinsky, Ilene; DeAngelo, Daniel J; Clark, Jennifer J; Lee, Stephanie J; Golub, Todd R; Wadleigh, Martha; Gilliland, D Gary; Levine, Ross L

2006-07-01

The JAK2V617F allele has recently been identified in patients with polycythemia vera (PV), essential thrombocytosis (ET), and myelofibrosis with myeloid metaplasia (MF). Subsequent analysis has shown that constitutive activation of the JAK-STAT signal transduction pathway is an important pathogenetic event in these patients, and that enzymatic inhibition of JAK2V617F may be of therapeutic benefit in this context. However, a significant proportion of patients with ET or MF are JAK2V617F-negative. We hypothesized that activation of the JAK-STAT pathway might also occur as a consequence of activating mutations in certain hematopoietic-specific cytokine receptors, including the erythropoietin receptor (EPOR), the thrombopoietin receptor (MPL), or the granulocyte-colony stimulating factor receptor (GCSFR). DNA sequence analysis of the exons encoding the transmembrane and juxtamembrane domains of EPOR, MPL, and GCSFR, and comparison with germline DNA derived from buccal swabs, identified a somatic activating mutation in the transmembrane domain of MPL (W515L) in 9% (4/45) of JAKV617F-negative MF. Expression of MPLW515L in 32D, UT7, or Ba/F3 cells conferred cytokine-independent growth and thrombopoietin hypersensitivity, and resulted in constitutive phosphorylation of JAK2, STAT3, STAT5, AKT, and ERK. Furthermore, a small molecule JAK kinase inhibitor inhibited MPLW515L-mediated proliferation and JAK-STAT signaling in vitro. In a murine bone marrow transplant assay, expression of MPLW515L, but not wild-type MPL, resulted in a fully penetrant myeloproliferative disorder characterized by marked thrombocytosis (Plt count 1.9-4.0 x 10(12)/L), marked splenomegaly due to extramedullary hematopoiesis, and increased reticulin fibrosis. Activation of JAK-STAT signaling via MPLW515L is an important pathogenetic event in patients with JAK2V617F-negative MF. The bone marrow transplant model of MPLW515L-mediated myeloproliferative disorders (MPD) exhibits certain features of human MF, including extramedullary hematopoiesis, splenomegaly, and megakaryocytic proliferation. Further analysis of positive and negative regulators of the JAK-STAT pathway is warranted in JAK2V617F-negative MPD.

Asparaginase-associated concurrence of hyperlipidemia, hyperglobulinemia, and thrombocytosis was successfully treated by centrifuge/membrane hybrid double-filtration plasmapheresis.

PubMed

Wang, Taina; Xu, Bin; Fan, Rong; Liu, Zhihong; Gong, Dehua

2016-01-01

Asparaginase-associated concurrence of hyperlipidemia, hyperglobulinemia, and thrombocytosis is a rare complication requiring aggressive lipoprotein apheresis, but no one of currently available lipoprotein apheresis methods can simultaneously resolve the 3 abnormalities. Herein, we reported a construction of double-filtration plasmapheresis (DFPP) using a combination of centrifugal/membranous plasma separation techniques to successfully treat a patient with hyperlipidemia, hyperglobulinemia, and thrombocytosis. A male presented with severe hyperlipidemia, hyperglobulinemia, and thrombocytosis during asparaginase treatment for NK/T-cell lymphoblastic lymphoma and was scheduled to receive lipoprotein apheresis. To simultaneously remove lipoproteins, immunoglobulin, and deplete platelets from blood, a centrifuge/membrane hybrid DFPP was constructed as following steps: plasma and part of platelets were separated first from whole blood by centrifugal technique and then divided by a fraction plasma separator into 2 parts: platelets and plasma components with large size, which were discarded; and those containing albumin, which were returned to blood with a supplement of extrinsic albumin solution. DFPP lasted 240 minutes uneventfully, processing 5450-mL plasma. The concentrations of plasma components before DFPP were as follows: triglycerides 38.22 mmol/L, total cholesterols 22.98 mmol/L, immunoglobulin A (IgA) 15.7 g/L, IgG 12.7 g/L, and IgM 14.3 g/L; whereas after treatment were 5.69 mmol/L, 2.38 mmol/L, 2.5 g/L, 7.7 g/L, and 0.4 g/L, respectively. The respective reduction ratio was 85.1%, 89.6%, 83.9%, 39.4%, and 96.9%. Platelet count decreased by 40.4% (from 612 × 10(9)/L to 365 × 10(9)/L). Centrifuge/membrane hybrid DFPP can simultaneously remove lipoproteins, immunoglobulin, and deplete platelets, with a success in treatment of asparaginase treatment-induced hyperlipidemia, hyperglobulinemia, and thrombocytosis, and may be useful for patients requiring DFPP but with particular situations. Copyright © 2015 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Striking hematological abnormalities in patients with microcephalic osteodysplastic primordial dwarfism type II (MOPD II): a potential role of pericentrin in hematopoiesis.

PubMed

Unal, Sule; Alanay, Yasemin; Cetin, Mualla; Boduroglu, Koray; Utine, Eda; Cormier-Daire, Valerie; Huber, Celine; Ozsurekci, Yasemin; Kilic, Esra; Simsek Kiper, Ozlem Pelin; Gumruk, Fatma

2014-02-01

Microcephalic osteodysplastic primordial dwarfism type II (MOPD II) is a rare primordial dwarfism that is similar to Seckel syndrome. Seckel syndrome is known to be associated with various hematological abnormalities; however, hematological findings in MOPD II patients have not been previously reported. The present study aimed to describe the hematological findings in a series of eight patients with MOPD II from a single center. The study included eight patients with MOPD II that were analyzed via molecular testing, and physical and laboratory examinations. Molecular testing showed that seven of the eight patients had pericentrin (PCNT) gene mutations. Hematological evaluation showed that 7 (87.5%) patients had thrombocytosis, 6 (75%) had leukocytosis, 5 (62.5%) had both leukocytosis and thrombocytosis, and 2 (25%) had anemia. We report leukocytosis and thrombocytosis as a common hematologic abnormality in patients with MOPD II. The present findings may improve our understanding of the potential function of the PCNT gene in hematopoietic cell proliferation and differentiation. © 2013 Wiley Periodicals, Inc.

An incomplete trafficking defect to the cell-surface leads to paradoxical thrombocytosis for human and murine MPL P106L.

PubMed

Favale, Fabrizia; Messaoudi, Kahia; Varghese, Leila N; Boukour, Siham; Pecquet, Christian; Gryshkova, Vitalina; Defour, Jean Philippe; Albu, Roxana-Irina; Bluteau, Olivier; Ballerini, Paola; Leverger, Guy; Plo, Isabelle; Debili, Najet; Raslova, Hana; Favier, Remi; Constantinescu, Stefan N; Vainchenker, William

2016-12-29

The mechanisms behind the hereditary thrombocytosis induced by the thrombopoietin (THPO) receptor MPL P106L mutant remain unknown. A complete trafficking defect to the cell surface has been reported, suggesting either weak constitutive activity or nonconventional THPO-dependent mechanisms. Here, we report that the thrombocytosis phenotype induced by MPL P106L belongs to the paradoxical group, where low MPL levels on platelets and mature megakaryocytes (MKs) lead to high serum THPO levels, whereas weak but not absent MPL cell-surface localization in earlier MK progenitors allows response to THPO by signaling and amplification of the platelet lineage. MK progenitors from patients showed no spontaneous growth and responded to THPO, and MKs expressed MPL on their cell surface at low levels, whereas their platelets did not respond to THPO. Transduction of MPL P106L in CD34 + cells showed that this receptor was more efficiently localized at the cell surface on immature than on mature MKs, explaining a proliferative response to THPO of immature cells and a defect in THPO clearance in mature cells. In a retroviral mouse model performed in Mpl -/- mice, MPL P106L could induce a thrombocytosis phenotype with high circulating THPO levels. Furthermore, we could select THPO-dependent cell lines with more cell-surface MPL P106L localization that was detected by flow cytometry and [ 125 I]-THPO binding. Altogether, these results demonstrate that MPL P106L is a receptor with an incomplete defect in trafficking, which induces a low but not absent localization of the receptor on cell surface and a response to THPO in immature MK cells. © 2016 by The American Society of Hematology.

Top-down Mass Spectrometry of Cardiac Myofilament Proteins in Health and Disease

PubMed Central

Ying, Peng; Serife, Ayaz-Guner; Deyang, Yu; Ying, Ge

2014-01-01

Myofilaments are composed of thin and thick filaments which coordinate with each other to regulate muscle contraction and relaxation. Posttranslational modifications (PTMs) together with genetic variations and alternative splicing of the myofilament proteins play essential roles in regulating cardiac contractility in health and disease. Therefore, a comprehensive characterization of the myofilament proteins in physiological and pathological conditions is essential for better understanding the molecular basis of cardiac function and dysfunction. Due to the vast complexity and dynamic nature of proteins, it is challenging to obtain a holistic view of myofilament protein modifications. In recent years, top-down mass spectrometry (MS) has emerged as a powerful approach to study isoform composition and PTMs of proteins owing to its advantage of complete sequence coverage and its ability to identify PTMs and sequence variants without a priori knowledge. In this review, we will discuss the application of top-down MS to study cardiac myofilaments and highlight the insights it provides into the understanding of molecular mechanisms in contractile dysfunction of heart failure. Particularly, recent results of cardiac troponin and tropomyosin modifications will be elaborated. The limitations and perspectives on the use of top-down MS for myofilament protein characterization will also be briefly discussed. PMID:24945106

Essential thrombocythaemia in two dogs.

PubMed

Favier, R P; van Leeuwen, M; Teske, E

2004-06-01

In this report two dogs with essential thrombocythaemia (ET) are described. Both dogs were presented more or less at the same time with a combination of reduced exercise tolerance and pale mucous membranes without any report of blood loss. Moderate-to-severe, Coomb's-negative anaemia and thrombocytosis (> 1249 x 10'/l) were present. In addition, the peripheral blood smear revealed the presence of basophilia and large numbers of abnormally shaped megakaryocytes in the bone marrow of both dogs. Treatment with vincristine (0.7 mg/m2 once intravenously) and hydroxyurea (500 mg/m2 p.o. per day) was started. Because of insufficient response to treatment after 3 weeks, the dosage of hydroxyurea was increased in both dogs to 2000 mg/m2 p.o. per day. The dogs deteriorated further, however, and were euthanized at 6 weeks after the start of treatment. Blood examination revealed pancytopenia in both dogs, most likely due to the myelosuppressive effects of high-dose hydroxyurea. A survey of veterinary literature on ET is presented, including a comparison of ET in humans.

JIP3 regulates neuronal radial migration by mediating TrkB axonal anterograde transport in the developing cerebral cortex.

PubMed

Ma, Huixian; Yu, Hui; Li, Ting; Zhao, Yan; Hou, Ming; Chen, Zheyu; Wang, Yue; Sun, Tao

2017-04-15

Radial migration is essential for the precise lamination and the coordinated function of the cerebral cortex. However, the molecular mechanisms for neuronal radial migration are not clear. Here, we report that c-Jun NH2-terminal kinase (JNK)-interacting protein-3 (JIP3) is highly expressed in the brain of embryonic mice and essential for radial migration. Knocking down JIP3 by in utero electroporation specifically perturbs the radial migration of cortical neurons but has no effect on neurogenesis and neuronal differentiation. Furthermore, we illustrate that JIP3 knockdown delays but does not block the migration of cortical neurons by investigating the distribution of neurons with JIP3 knocked down in the embryo and postnatal mouse. Finally, we find that JIP3 regulates cortical neuronal migration by mediating TrkB axonal anterograde transport during brain development. These findings deepen our understanding of the regulation of neuronal development by JIP3 and provide us a novel view on the regulating mechanisms of neuronal radial migration. Copyright © 2017 Elsevier Inc. All rights reserved.

Cyclin D1 down-regulation is essential for DBC2's tumor suppressor function

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

Yoshihara, Takashi; Collado, Denise; Hamaguchi, Masaaki

2007-07-13

The expression of tumor suppressor gene DBC2 causes certain breast cancer cells to stop growing [M. Hamaguchi, J.L. Meth, C. Von Klitzing, W. Wei, D. Esposito, L. Rodgers, T. Walsh, P. Welcsh, M.C. King, M.H. Wigler, DBC2, a candidate for a tumor suppressor gene involved in breast cancer, Proc. Natl. Acad. Sci. USA 99 (2002) 13647-13652]. Recently, DBC2 was found to participate in diverse cellular functions such as protein transport, cytoskeleton regulation, apoptosis, and cell cycle control [V. Siripurapu, J.L. Meth, N. Kobayashi, M. Hamaguchi, DBC2 significantly influences cell cycle, apoptosis, cytoskeleton, and membrane trafficking pathways. J. Mol. Biol. 346more » (2005) 83-89]. Its tumor suppression mechanism, however, remains unclear. In this paper, we demonstrate that DBC2 suppresses breast cancer proliferation through down-regulation of Cyclin D1 (CCND1). Additionally, the constitutional overexpression of CCND1 prevented the negative impact of DBC2 expression on their growth. Under a CCND1 promoter, the expression of CCNE1 exhibited the same protective effect. Our results indicate that the down-regulation of CCND1 is an essential step for DBC2's growth suppression of cancer cells. We believe that this discovery contributes to a better understanding of DBC2's tumor suppressor function.« less

Polymerase III transcription factor B activity is reduced in extracts of growth-restricted cells.

PubMed Central

Tower, J; Sollner-Webb, B

1988-01-01

Extracts of cells that are down-regulated for transcription by RNA polymerase I and RNA polymerase III exhibit a reduced in vitro transcriptional capacity. We have recently demonstrated that the down-regulation of polymerase I transcription in extracts of cycloheximide-treated and stationary-phase cells results from a lack of an activated subform of RNA polymerase I which is essential for rDNA transcription. To examine whether polymerase III transcriptional down-regulation occurs by a similar mechanism, the polymerase III transcription factors were isolated and added singly and in pairs to control cell extracts and to extracts of cells that had reduced polymerase III transcriptional activity due to cycloheximide treatment or growth into stationary phase. These down-regulations result from a specific reduction in TFIIIB; TFIIIC and polymerase III activities remain relatively constant. Thus, although transcription by both polymerase III and polymerase I is substantially decreased in extracts of growth-arrested cells, this regulation is brought about by reduction of different kinds of activities: a component of the polymerase III stable transcription complex in the former case and the activated subform of RNA polymerase I in the latter. Images PMID:3352599

Budding Yeast ATM/ATR Control Meiotic Double-Strand Break (DSB) Levels by Down-Regulating Rec114, an Essential Component of the DSB-machinery

PubMed Central

Carballo, Jesús A.; Panizza, Silvia; Serrentino, Maria Elisabetta; Johnson, Anthony L.; Geymonat, Marco; Borde, Valérie; Klein, Franz; Cha, Rita S.

2013-01-01

An essential feature of meiosis is Spo11 catalysis of programmed DNA double strand breaks (DSBs). Evidence suggests that the number of DSBs generated per meiosis is genetically determined and that this ability to maintain a pre-determined DSB level, or “DSB homeostasis”, might be a property of the meiotic program. Here, we present direct evidence that Rec114, an evolutionarily conserved essential component of the meiotic DSB-machinery, interacts with DSB hotspot DNA, and that Tel1 and Mec1, the budding yeast ATM and ATR, respectively, down-regulate Rec114 upon meiotic DSB formation through phosphorylation. Mimicking constitutive phosphorylation reduces the interaction between Rec114 and DSB hotspot DNA, resulting in a reduction and/or delay in DSB formation. Conversely, a non-phosphorylatable rec114 allele confers a genome-wide increase in both DSB levels and in the interaction between Rec114 and the DSB hotspot DNA. These observations strongly suggest that Tel1 and/or Mec1 phosphorylation of Rec114 following Spo11 catalysis down-regulates DSB formation by limiting the interaction between Rec114 and DSB hotspots. We also present evidence that Ndt80, a meiosis specific transcription factor, contributes to Rec114 degradation, consistent with its requirement for complete cessation of DSB formation. Loss of Rec114 foci from chromatin is associated with homolog synapsis but independent of Ndt80 or Tel1/Mec1 phosphorylation. Taken together, we present evidence for three independent ways of regulating Rec114 activity, which likely contribute to meiotic DSBs-homeostasis in maintaining genetically determined levels of breaks. PMID:23825959

BMP6 down-regulates GDNF expression through SMAD1/5 and ERK1/2 signaling pathways in human granulosa-lutein cells.

PubMed

Zhang, Xin-Yue; Chang, Hsun-Ming; Taylor, Elizabeth L; Leung, Peter C K; Liu, Rui-Zhi

2018-05-09

Bone morphogenetic protein 6 (BMP6) is a critical regulator of follicular development that is expressed in mammalian oocytes and granulosa cells. Glial cell line-derived neurotrophic factor (GDNF) is an intraovarian neurotrophic factor that plays an essential role in regulating mammalian oocyte maturation. The aim of this study was to investigate the effect of BMP6 on the regulation of GDNF expression and the potential underlying mechanisms. We used an established immortalized human granulosa cell line (SVOG cells) and primary human granulosa-lutein cells as in vitro cell models. Our results showed that BMP6 significantly down-regulated the expression of GDNF in both SVOG and primary human granulosa-lutein cells. Using dual inhibition approaches (kinase receptor inhibitor and small interfering RNA knockdown), our results showed that both ALK2 and ALK3 are involved in BMP6-induced down-regulation of GDNF. In addition, BMP6 induced the phosphorylation of SMAD1/5/8 and ERK1/2 but not AKT or p38. Among three downstream mediators, both SMAD1 and SMAD5 are involved in BMP6-induced down-regulation of GDNF. Moreover, concomitant knockdown of endogenous SMAD4 and inhibition of ERK1/2 activity completely reversed BMP6-induced down-regulation of GDNF, indicating that both SMAD and ERK1/2 signaling pathways are required for the regulatory effect of BMP6 on GDNF expression. Our findings suggest an additional role for an intrafollicular growth factor in regulating follicular function through their paracrine interactions in human granulosa cells.

Q fever as a cause of fever of unknown origin and thrombocytosis: first molecular evidence of Coxiella burnetii in Brazil.

PubMed

Lemos, Elba R S; Rozental, Tatiana; Mares-Guia, Maria Angélica M; Almeida, Daniele N P; Moreira, Namir; Silva, Raphael G; Barreira, Jairo D; Lamas, Cristiane C; Favacho, Alexsandra R; Damasco, Paulo V

2011-01-01

We report a case of Q fever in a man who presented with fever of 40 days duration associated with thrombocytosis. Serological and molecular analysis (polymerase chain reaction) confirmed infection with Coxiella burnetii. A field study was conducted by collecting blood samples from the patient's family and from the animals in the patient's house. The patient's wife and 2 of 13 dogs showed seroreactivity. Our data indicate that C. burnetii may be an underrecognized cause of fever in Brazil and emphasize the need for clinicians to consider Q fever in patients with a febrile illness, particularly those with a history of animal contact.

Prognostic significance of platelet count changes during hospitalization for community-acquired pneumonia.

PubMed

Gorelik, Oleg; Izhakian, Shimon; Barchel, Dana; Almoznino-Sarafian, Dorit; Tzur, Irma; Swarka, Muhareb; Beberashvili, Ilia; Feldman, Leonid; Cohen, Natan; Shteinshnaider, Miriam

2017-06-01

The prognostic significance of platelet count (PC) changes during hospitalization for community-acquired pneumonia (CAP) has not been investigated. For 976 adults, clinical data during hospitalization for CAP and all-cause mortality following discharge were compared according to ΔPC (PC on discharge minus PC on admission): groups A (declining PC, ΔPC < -50 × 10 9 /l), B (stable PC, ΔPC ± 50 × 10 9 /l), and C (rising PC, ΔPC >50 × 10 9 /l), and according to the presence of thrombocytopenia, normal PC, and thrombocytosis on admission/discharge. Groups A, B, and C comprised 7.9%, 46.5%, and 45.6% of patients, respectively. On hospital admission/discharge, thrombocytopenia, normal PC, and thrombocytosis were observed in 12.8%/6.4%, 84.1%/84.4%, and 3.1%/9.2% of patients, respectively. The respective 90-day, 3-year, and total (median follow-up of 54 months) mortality rates were significantly higher: in group A (40.3%, 63.6%, and 72.7%), compared to groups B (12.3%, 31.5%, and 39.0%) and C (4.9%, 17.3%, and 25.4%), p < 0.001; and in patients with thrombocytopenia at discharge (27.4%, 48.4%, and 51.6%), compared to those with normal PC (10.2%, 26.9%, and 35.4%) and thrombocytosis (8.9%, 17.8%, and 24.4%) at discharge (p < 0.001). Mortality rates were comparable among groups with thrombocytopenia, normal PC, and thrombocytosis at admission (p = 0.6). In the entire sample, each 100 × 10 9 /l increment of ΔPC strongly predicted lower mortality (p < 0.001, relative risk 0.73, 95% confidence interval 0.64-0.83). In conclusion, PC changes are common among CAP inpatients. Rising PC throughout hospitalization is a powerful predictor of better survival, while declining PC predicts poor outcome. Evaluation of PC changes during hospitalization for CAP may provide useful prognostic information.

CXC chemokine ligand 4 (CXCL4) down-regulates CC chemokine receptor expression on human monocytes.

PubMed

Schwartzkopff, Franziska; Petersen, Frank; Grimm, Tobias Alexander; Brandt, Ernst

2012-02-01

During acute inflammation, monocytes are essential in abolishing invading micro-organisms and encouraging wound healing. Recruitment by CC chemokines is an important step in targeting monocytes to the inflamed tissue. However, cell surface expression of the corresponding chemokine receptors is subject to regulation by various endogenous stimuli which so far have not been comprehensively identified. We report that the platelet-derived CXC chemokine ligand 4 (CXCL4), a known activator of human monocytes, induces down-regulation of CC chemokine receptors (CCR) 1, -2, and -5, resulting in drastic impairment of monocyte chemotactic migration towards cognate CC chemokine ligands (CCL) for these receptors. Interestingly, CXCL4-mediated down-regulation of CCR1, CCR2 and CCR5 was strongly dependent on the chemokine's ability to stimulate autocrine/paracrine release of TNF-α. In turn, TNF-α induced the secretion CCL3 and CCL4, two chemokines selective for CCR1 and CCR5, while the secretion of CCR2-ligand CCL2 was TNF-α-independent. Culture supernatants of CXCL4-stimulated monocytes as well as chemokine-enriched preparations thereof reproduced CXCL4-induced CCR down-regulation. In conclusion, CXCL4 may act as a selective regulator of monocyte migration by stimulating the release of autocrine, receptor-desensitizing chemokine ligands. Our results stress a co-ordinating role for CXCL4 in the cross-talk between platelets and monocytes during early inflammation.

The mouse homeobox gene Noto regulates node morphogenesis, notochordal ciliogenesis, and left–right patterning

PubMed Central

Beckers, Anja; Alten, Leonie; Viebahn, Christoph; Andre, Philipp; Gossler, Achim

2007-01-01

The mouse homeobox gene Noto represents the homologue of zebrafish floating head (flh) and is expressed in the organizer node and in the nascent notochord. Previous analyses suggested that Noto is required exclusively for the formation of the caudal part of the notochord. Here, we show that Noto is also essential for node morphogenesis, controlling ciliogenesis in the posterior notochord, and the establishment of laterality, whereas organizer functions in anterior–posterior patterning are apparently not compromised. In mutant embryos, left–right asymmetry of internal organs and expression of laterality markers was randomized. Mutant posterior notochord regions were variable in size and shape, cilia were shortened with highly irregular axonemal microtubuli, and basal bodies were, in part, located abnormally deep in the cytoplasm. The transcription factor Foxj1, which regulates the dynein gene Dnahc11 and is required for the correct anchoring of basal bodies in lung epithelial cells, was down-regulated in mutant nodes. Likewise, the transcription factor Rfx3, which regulates cilia growth, was not expressed in Noto mutants, and various other genes important for cilia function or assembly such as Dnahc5 and Nphp3 were down-regulated. Our results establish Noto as an essential regulator of node morphogenesis and ciliogenesis in the posterior notochord, and suggest Noto acts upstream of Foxj1 and Rfx3. PMID:17884984

Bilateral visual loss and cerebral infarction after spleen embolization in a trauma patient with idiopathic thrombocytopenic purpura: A case report.

PubMed

Wang, Wei-Ting; Li, Yu-Yu; Lin, Wan-Ching; Chen, Jen-Yin; Lan, Kuo-Mao; Sun, Cheuk-Kwan; Hung, Kuo-Chuan

2018-04-01

Splenic artery embolization (SAE) is a common procedure in trauma patients with blunt splenic injuries. We report a case of acute ischemic stroke following orthopedic surgery in a patient with post-SAE reactive thrombocytosis. A 37-year-old woman with idiopathic thrombocytopenic purpura (ITP) suffered from multiple trauma scheduled for open reduction and internal fixation for right tibial and left radius fracture five days after SAE. The patient did not have any thromboembolic complications, although the platelet counts increased from 43 × 10/L to 568 × 10/L within two days after SAE. Surgery was completed under general anesthesia with tracheal intubation without complications. The patient complained of visual loss followed by limb weakness on the fourth and eighth hour postoperatively. Magnetic resonance imaging (MRI) of head demonstrated ischemic change over bilateral basal ganglia, and occipital areas, suggesting the diagnosis of cortical blindness. To suppress platelet count and avoid platelet hyper-aggregation, anti-platelet drug (i.e., oral aspirin 100 mg daily), hydration, and hydroxyurea (i.e., 20 mg/kg daily) were used for the treatment of reactive thrombocytosis. Although right-sided hemiparesis persisted, the patient reported mild visual recovery. She was discharged four months after SAE with active rehabilitation. Our report highlights an increased risk of acute arterial thromboembolic events in patients with reactive thrombocytosis, especially those undergoing surgery.

Inhibition of invasion by glycogen synthase kinase-3 beta inhibitors through dysregulation of actin re-organisation via down-regulation of WAVE2.

PubMed

Yoshino, Yuki; Suzuki, Manami; Takahashi, Hidekazu; Ishioka, Chikashi

2015-08-14

Cancer cell invasion is a critical phenomenon in cancer pathogenesis. Glycogen synthase kinase-3β (GSK-3β) has been reported to regulate cancer cell invasion both negatively and positively. Thus, the net effect of GSK-3β on invasion is unclear. In this report, we showed that GSK-3β inhibitors induced dysregulation of the actin cytoskeleton and functional insufficiency of focal adhesion, which resulted in suppressed invasion. In addition, WAVE2, an essential molecule for actin fibre branching, was down-regulated after GSK-3β inhibition. Collectively, we propose that the WAVE2-actin cytoskeleton axis is an important target of GSK-3β inhibitors in cancer cell invasion. Copyright © 2015 Elsevier Inc. All rights reserved.

Identifying chromatin readers using a SILAC-based histone peptide pull-down approach.

PubMed

Vermeulen, Michiel

2012-01-01

Posttranslational modifications (PTMs) on core histones regulate essential processes inside the nucleus such as transcription, replication, and DNA repair. An important function of histone PTMs is the recruitment or stabilization of chromatin-modifying proteins, which are also called chromatin "readers." We have developed a generic SILAC-based peptide pull-down approach to identify such readers for histone PTMs in an unbiased manner. In this chapter, the workflow behind this method will be presented in detail. Copyright © 2012 Elsevier Inc. All rights reserved.

Thrombocythemia and Thrombocytosis

MedlinePlus

... Learn more about getting to NIH Get Email Alerts Receive automatic alerts about NHLBI related news and ... Connect With Us Contact Us Directly Get Email Alerts Receive automatic alerts about NHLBI related news and ...

Calcium - ionized

MedlinePlus

... diuretics Thrombocytosis (high platelet count) Tumors Vitamin A excess Vitamin D excess Lower-than-normal levels may be due to: Hypoparathyroidism Malabsorption Osteomalacia Pancreatitis Renal failure Rickets Vitamin D deficiency Alternative Names Free calcium; Ionized calcium ...

MicroRNA-Mediated Down-Regulation of M-CSF Receptor Contributes to Maturation of Mouse Monocyte-Derived Dendritic Cells

PubMed Central

Riepsaame, Joey; van Oudenaren, Adri; den Broeder, Berlinda J. H.; van IJcken, Wilfred F. J.; Pothof, Joris; Leenen, Pieter J. M.

2013-01-01

Dendritic cell (DC) maturation is a tightly regulated process that requires coordinated and timed developmental cues. Here we investigate whether microRNAs are involved in this process. We identify microRNAs in mouse GM-CSF-generated, monocyte-related DC (GM-DC) that are differentially expressed during both spontaneous and LPS-induced maturation and characterize M-CSF receptor (M-CSFR), encoded by the Csf1r gene, as a key target for microRNA-mediated regulation in the final step toward mature DC. MicroRNA-22, -34a, and -155 are up-regulated in mature MHCIIhi CD86hi DC and mediate Csf1r mRNA and protein down-regulation. Experimental inhibition of Csf1r-targeting microRNAs in vitro results not only in sustained high level M-CSFR protein expression but also in impaired DC maturation upon stimulation by LPS. Accordingly, over-expression of Csf1r in GM-DC inhibits terminal differentiation. Taken together, these results show that developmentally regulated microRNAs control Csf1r expression, supplementing previously identified mechanisms that regulate its transcription and protein surface expression. Furthermore, our data indicate a novel function for Csf1r in mouse monocyte-derived DC, showing that down-regulation of M-CSFR expression is essential for final DC maturation. PMID:24198819

A dual function for Deep orange in programmed autophagy in the Drosophila melanogaster fat body.

PubMed

Lindmo, Karine; Simonsen, Anne; Brech, Andreas; Finley, Kim; Rusten, Tor Erik; Stenmark, Harald

2006-07-01

Lysosomal degradation of cytoplasm by way of autophagy is essential for cellular amino acid homeostasis and for tissue remodeling. In insects such as Drosophila, autophagy is developmentally upregulated in the larval fat body prior to metamorphosis. Here, autophagy is induced by the hormone ecdysone through down-regulation of the autophagy-suppressive phosphoinositide 3-kinase (PI3K) signaling pathway. In yeast, Vps18 and other members of the HOPS complex have been found essential for autophagic degradation. In Drosophila, the Vps18 homologue Deep orange (Dor) has previously been shown to mediate fusion of multivesicular endosomes with lysosomes. A requirement of Dor for ecdysone-mediated chromosome puffing has also been reported. In the present report, we have tested the hypothesis that Dor may control programmed autophagy at the level of ecdysone signaling as well as by mediating autophagosome-to-lysosome fusion. We show that dor mutants are defective in programmed autophagy and provide evidence that autophagy is blocked at two levels. First, PI3K activity was not down-regulated correctly in dor larvae, which correlated with a decrease in ecdysone reporter activity. The down-regulation of PI3K activity was restored by feeding ecdysone to the mutant larvae. Second, neither exogenous ecdysone nor overexpression of PTEN, a silencer of PI3K signaling, restored fusion of autophagosomes with lysosomes in the fat body of dor mutants. These results indicate that Dor controls autophagy indirectly, via ecdysone signaling, as well as directly, via autolysosomal fusion.

A role of NF-E2 in chronic inflammation and clonal evolution in essential thrombocythemia, polycythemia vera and myelofibrosis?

PubMed

Hasselbalch, Hans C

2014-02-01

A novel murine model for myeloproliferative neoplasms (MPNs) generated by overexpression of the transcription factor NF-E2 has recently been described. Sustained overexpression of NF-E2 in this model induced myeloid expansion with anemia, leukocytosis and thrombocytosis. Herein, it is debated if NF-E2 overexpression also might have induced a sustained state of in vivo leukocyte and platelet activation with chronic and self-perpetuating production of inflammatory products from activated leukocytes and platelets. If so, this novel murine model also may excellently describe the deleterious impact of sustained chronic NF-E2 overexpression during uncontrolled chronic inflammation upon the hematopoietic system--the development of clonal myeloproliferation. Accordingly, this novel murine model may also have delivered the proof of concept of chronic inflammation as a trigger and driver of clonal evolution in MPNs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Polo-like kinase 1 expression is suppressed by CCAAT/enhancer-binding protein α to mediate colon carcinoma cell differentiation and apoptosis.

PubMed

Dasgupta, Nirmalya; Thakur, Bhupesh Kumar; Ta, Atri; Das, Sayan; Banik, George; Das, Santasabuj

2017-07-01

Human polo-like kinase 1 (PLK1), a highly conserved serine/threonine kinase is a key player in several essential cell-cycle events. PLK1 is considered an oncogene and its overexpression often correlates with poor prognosis of cancers, including colorectal cancer (CRC). However, regulation of PLK1 expression in colorectal cells was never studied earlier and it is currently unknown if PLK1 regulates differentiation and apoptosis of CRC. PLK1 expression was analyzed by real-time PCR and western blotting. Transcriptional regulation was studied by reporter assay, gene knock-down, EMSA and ChIP. PLK1 expression was down-regulated during butyrate-induced differentiation of HT-29 and other CRC cells. Also, PLK1 down-regulation mediated the role of butyrate in CRC differentiation and apoptosis. We report here a novel transcriptional regulation of PLK1 by butyrate. Transcription factors CCAAT/enhancer-binding protein α (C/EBPα) and Oct-1 share an overlapping binding site over the PLK1 promoter. Elevated levels of C/EBPα by butyrate treatment of CRC cells competed out the activator protein Oct-1 from binding to the PLK1 promoter and sequestered it. Binding of C/EBPα was associated with increased deacetylation near the transcription start site (TSS) of the PLK1 promoter, which abrogated transcription through reduced recruitment of RNA polymerase II. We also found a synergistic role between the synthetic PLK1-inhibitor SBE13 and butyrate on the apoptosis of CRC cells. This study offered a novel p53-independent regulation of PLK1 during CRC differentiation and apoptosis. Down-regulation of PLK1 is one of the mechanisms underlying the anti-cancer role of dietary fibre-derived butyrate in CRC. Copyright © 2017 Elsevier B.V. All rights reserved.

Glycoprotein D actively induces rapid internalization of two nectin-1 isoforms during herpes simplex virus entry

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

Stiles, Katie M., E-mail: stileskm@mail.med.upenn.ed; Krummenacher, Claude

2010-03-30

Entry of herpes simplex virus (HSV) occurs either by fusion at the plasma membrane or by endocytosis and fusion with an endosome. Binding of glycoprotein D (gD) to a receptor such as nectin-1 is essential in both cases. We show that virion gD triggered the rapid down-regulation of nectin-1 with kinetics similar to those of virus entry. In contrast, nectin-1 was not constitutively recycled from the surface of uninfected cells. Both the nectin-1alpha and beta isoforms were internalized in response to gD despite having different cytoplasmic tails. However, deletion of the nectin-1 cytoplasmic tail slowed down-regulation of nectin-1 and internalizationmore » of virions. These data suggest that nectin-1 interaction with a cytoplasmic protein is not required for its down-regulation. Overall, this study shows that gD binding actively induces the rapid internalization of various forms of nectin-1. We suggest that HSV activates a nectin-1 internalization pathway to use for endocytic entry.« less

Down-regulation of zinc transporter 8 (SLC30A8) in pancreatic beta-cells promotes cell survival

USDA-ARS?s Scientific Manuscript database

The pancreatic islet contains high levels of zinc in granular vesicles of beta-cells where insulin is matured, crystallized, and stored before secretion. Zinc is an essential co-factor for insulin crystallization forming dense core in secretory granules. In insulin-containing secretory granules, zin...

Down-regulation of zinc transporter 8 (SLC30A8) in pancreatic beta-cells promotes cell survival.

USDA-ARS?s Scientific Manuscript database

The pancreatic islet contains high levels of zinc in granular vesicles of ß-cells where insulin is matured, crystallized, and stored before secretion. Zinc is an essential co-factor for insulin crystallization forming dense cores in secretory granules. In insulin-containing secretory granules, zinc ...

Renovascular hypertension associated with JAK2 V617F positive myeloproliferative neoplasms treated with angioplasty: 2 cases and literature review.

PubMed

Mishima, Eikan; Suzuki, Takehiro; Takeuchi, Yoichi; Seiji, Kazumasa; Fukuhara, Noriko; Takase, Kei; Harigae, Hideo; Abe, Takaaki; Ito, Sadayoshi

2018-04-01

Myeloproliferative neoplasms (MPNs) with Janus kinase 2 (JAK2) mutation are associated with a high risk for occlusive vascular diseases. We report 2 cases of renovascular hypertension associated with JAK2 V617F mutation-positive MPNs and provide a literature review. In Case 1, a 63-year-old woman had resistant hypertension, massive proteinuria, and erythrocytosis. Evaluations revealed right renal artery stenosis causing renovascular hypertension and polycythemia vera with JAK2 V617F mutation. Renin-angiotensin system inhibitors and subsequent angioplasty controlled the blood pressure and the proteinuria resolved. In Case 2, a 74-year-old woman had resistant hypertension and thrombocytosis. Evaluations confirmed left renal artery stenosis and essential thrombocythemia with JAK2 V617F. Angioplasty cured the hypertension. A literature review of 18 cases revealed the following as the most common characteristics of MPN-associated renovascular hypertension: manifests primarily in women; is associated with untreated polycythemia vera and essential thrombocythemia, concomitant leukocytosis, and JAK2 mutation positivity; and is responsive to angioplasty. This report demonstrates that JAK2 mutation-positive MPNs are a less common but important underlying cause of adult renovascular hypertension. ©2018 Wiley Periodicals, Inc.

The Fertilization-Induced DNA Replication Factor MCM6 of Maize Shuttles between Cytoplasm and Nucleus, and Is Essential for Plant Growth and Development1

PubMed Central

Dresselhaus, Thomas; Srilunchang, Kanok-orn; Leljak-Levanić, Dunja; Schreiber, Daniela N.; Garg, Preeti

2006-01-01

The eukaryotic genome is duplicated exactly once per cell division cycle. A strategy that limits every replication origin to a single initiation event is tightly regulated by a multiprotein complex, which involves at least 20 protein factors. A key player in this regulation is the evolutionary conserved hexameric MCM2-7 complex. From maize (Zea mays) zygotes, we have cloned MCM6 and characterized this essential gene in more detail. Shortly after fertilization, expression of ZmMCM6 is strongly induced. During progression of zygote and proembryo development, ZmMCM6 transcript amounts decrease and are low in vegetative tissues, where expression is restricted to tissues containing proliferating cells. The highest protein amounts are detectable about 6 to 20 d after fertilization in developing kernels. Subcellular localization studies revealed that MCM6 protein shuttles between cytoplasm and nucleoplasm in a cell cycle-dependent manner. ZmMCM6 is taken up by the nucleus during G1 phase and the highest protein levels were observed during late G1/S phase. ZmMCM6 is excluded from the nucleus during late S, G2, and mitosis. Transgenic maize was generated to overexpress and down-regulate ZmMCM6. Plants displaying minor antisense transcript amounts were reduced in size and did not develop cobs to maturity. Down-regulation of ZmMCM6 gene activity seems also to affect pollen development because antisense transgenes could not be propagated via pollen to wild-type plants. In summary, the transgenic data indicate that MCM6 is essential for both vegetative as well as reproductive growth and development in plants. PMID:16407440

The fertilization-induced DNA replication factor MCM6 of maize shuttles between cytoplasm and nucleus, and is essential for plant growth and development.

PubMed

Dresselhaus, Thomas; Srilunchang, Kanok-Orn; Leljak-Levanic, Dunja; Schreiber, Daniela N; Garg, Preeti

2006-02-01

The eukaryotic genome is duplicated exactly once per cell division cycle. A strategy that limits every replication origin to a single initiation event is tightly regulated by a multiprotein complex, which involves at least 20 protein factors. A key player in this regulation is the evolutionary conserved hexameric MCM2-7 complex. From maize (Zea mays) zygotes, we have cloned MCM6 and characterized this essential gene in more detail. Shortly after fertilization, expression of ZmMCM6 is strongly induced. During progression of zygote and proembryo development, ZmMCM6 transcript amounts decrease and are low in vegetative tissues, where expression is restricted to tissues containing proliferating cells. The highest protein amounts are detectable about 6 to 20 d after fertilization in developing kernels. Subcellular localization studies revealed that MCM6 protein shuttles between cytoplasm and nucleoplasm in a cell cycle-dependent manner. ZmMCM6 is taken up by the nucleus during G1 phase and the highest protein levels were observed during late G1/S phase. ZmMCM6 is excluded from the nucleus during late S, G2, and mitosis. Transgenic maize was generated to overexpress and down-regulate ZmMCM6. Plants displaying minor antisense transcript amounts were reduced in size and did not develop cobs to maturity. Down-regulation of ZmMCM6 gene activity seems also to affect pollen development because antisense transgenes could not be propagated via pollen to wild-type plants. In summary, the transgenic data indicate that MCM6 is essential for both vegetative as well as reproductive growth and development in plants.

[Apoptosis and activity changes of telomerase induced by essential oil from pine needles in HepG2 cell line].

PubMed

Wei, Feng-xiang; Li, Mei-yu; Song, Yu-hong; Li, Hong-zhi

2008-08-01

To study the effects of essential oil extracted from pine needles on HepG2 cell line. HepG2 cells were treated with essential oil extracted from pine needles. Cell growth rate was determined with MTF assay, cell morphologic changes were examined under transmission electromicroscope and HE straining. Flow cytometry was used to exmine apoptotic cells. Bcl-2 gene expression was determined by flow cytometry and telomerase activity by TRAP assay. Essential oils from pine needles could not only repress the growth of HepG2 cells significantly, but also induce apoptosis to them. Both dose-effect and time-effect relationship could be confirmed. Typical morphology changes of apoptosis such as nuclear enrichment and karyorrhexis were observed through transmission electromicroscope and HE straining. Telomerase activity was down regulated in the essential oil extracted from pine needles induced apoptotic cells. The expression of bcl-2 gene was suppressed after the essential oil from pine needles treatement. The essential oil extracted from pine needles can inhibit cell growth of HepG2 cell line and induce apoptosis, which may associate with inhibition of telomerase activity and bcl-2 may be involved in the regulation of telomerase activity.

A dual function for Deep orange in programmed autophagy in the Drosophila melanogaster fat body

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

Lindmo, Karine; Simonsen, Anne; Brech, Andreas

2006-07-01

Lysosomal degradation of cytoplasm by way of autophagy is essential for cellular amino acid homeostasis and for tissue remodeling. In insects such as Drosophila, autophagy is developmentally upregulated in the larval fat body prior to metamorphosis. Here, autophagy is induced by the hormone ecdysone through down-regulation of the autophagy-suppressive phosphoinositide 3-kinase (PI3K) signaling pathway. In yeast, Vps18 and other members of the HOPS complex have been found essential for autophagic degradation. In Drosophila, the Vps18 homologue Deep orange (Dor) has previously been shown to mediate fusion of multivesicular endosomes with lysosomes. A requirement of Dor for ecdysone-mediated chromosome puffing hasmore » also been reported. In the present report, we have tested the hypothesis that Dor may control programmed autophagy at the level of ecdysone signaling as well as by mediating autophagosome-to-lysosome fusion. We show that dor mutants are defective in programmed autophagy and provide evidence that autophagy is blocked at two levels. First, PI3K activity was not down-regulated correctly in dor larvae, which correlated with a decrease in ecdysone reporter activity. The down-regulation of PI3K activity was restored by feeding ecdysone to the mutant larvae. Second, neither exogenous ecdysone nor overexpression of PTEN, a silencer of PI3K signaling, restored fusion of autophagosomes with lysosomes in the fat body of dor mutants. These results indicate that Dor controls autophagy indirectly, via ecdysone signaling, as well as directly, via autolysosomal fusion.« less

Top-down cortical input during NREM sleep consolidates perceptual memory.

PubMed

Miyamoto, D; Hirai, D; Fung, C C A; Inutsuka, A; Odagawa, M; Suzuki, T; Boehringer, R; Adaikkan, C; Matsubara, C; Matsuki, N; Fukai, T; McHugh, T J; Yamanaka, A; Murayama, M

2016-06-10

During tactile perception, long-range intracortical top-down axonal projections are essential for processing sensory information. Whether these projections regulate sleep-dependent long-term memory consolidation is unknown. We altered top-down inputs from higher-order cortex to sensory cortex during sleep and examined the consolidation of memories acquired earlier during awake texture perception. Mice learned novel textures and consolidated them during sleep. Within the first hour of non-rapid eye movement (NREM) sleep, optogenetic inhibition of top-down projecting axons from secondary motor cortex (M2) to primary somatosensory cortex (S1) impaired sleep-dependent reactivation of S1 neurons and memory consolidation. In NREM sleep and sleep-deprivation states, closed-loop asynchronous or synchronous M2-S1 coactivation, respectively, reduced or prolonged memory retention. Top-down cortical information flow in NREM sleep is thus required for perceptual memory consolidation. Copyright © 2016, American Association for the Advancement of Science.

Lithium Down-regulates Histone Deacetylase 1 (HDAC1) and Induces Degradation of Mutant Huntingtin*

PubMed Central

Wu, Shuai; Zheng, Shui-Di; Huang, Hong-Ling; Yan, Li-Chong; Yin, Xiao-Fei; Xu, Hai-Neng; Zhang, Kang-Jian; Gui, Jing-Hua; Chu, Liang; Liu, Xin-Yuan

2013-01-01

Lithium is an effective mood stabilizer that has been clinically used to treat bipolar disorder for several decades. Recent studies have suggested that lithium possesses robust neuroprotective and anti-tumor properties. Thus far, a large number of lithium targets have been discovered. Here, we report for the first time that HDAC1 is a target of lithium. Lithium significantly down-regulated HDAC1 at the translational level by targeting HDAC1 mRNA. We also showed that depletion of HDAC1 is essential for the neuroprotective effects of lithium and for the lithium-mediated degradation of mutant huntingtin through the autophagic pathway. Our studies explain the multiple functions of lithium and reveal a novel mechanism for the function of lithium in neurodegeneration. PMID:24165128

Specific down-regulation of spermatogenesis genes targeted by 22G RNAs in hybrid sterile males associated with an X-Chromosome introgression.

PubMed

Li, Runsheng; Ren, Xiaoliang; Bi, Yu; Ho, Vincy Wing Sze; Hsieh, Chia-Ling; Young, Amanda; Zhang, Zhihong; Lin, Tingting; Zhao, Yanmei; Miao, Long; Sarkies, Peter; Zhao, Zhongying

2016-09-01

Hybrid incompatibility (HI) prevents gene flow between species, thus lying at the heart of speciation genetics. One of the most common HIs is male sterility. Two superficially contradictory observations exist for hybrid male sterility. First, an introgression on the X Chromosome is more likely to produce male sterility than on autosome (so-called large-X theory); second, spermatogenesis genes are enriched on the autosomes but depleted on the X Chromosome (demasculinization of X Chromosome). Analysis of gene expression in Drosophila hybrids suggests a genetic interaction between the X Chromosome and autosomes that is essential for male fertility. However, the prevalence of such an interaction and its underlying mechanism remain largely unknown. Here we examine the interaction in nematode species by contrasting the expression of both coding genes and transposable elements (TEs) between hybrid sterile males and its parental nematode males. We use two lines of hybrid sterile males, each carrying an independent introgression fragment from Caenorhabditis briggsae X Chromosome in an otherwise Caenorhabditis nigoni background, which demonstrate similar defects in spermatogenesis. We observe a similar pattern of down-regulated genes that are specific for spermatogenesis between the two hybrids. Importantly, the down-regulated genes caused by the X Chromosome introgressions show a significant enrichment on the autosomes, supporting an epistatic interaction between the X Chromosome and autosomes. We investigate the underlying mechanism of the interaction by measuring small RNAs and find that a subset of 22G RNAs specifically targeting the down-regulated spermatogenesis genes is significantly up-regulated in hybrids, suggesting that perturbation of small RNA-mediated regulation may contribute to the X-autosome interaction. © 2016 Li et al.; Published by Cold Spring Harbor Laboratory Press.

Differential Role of Poly(ADP-ribose) polymerase in D. discoideum growth and development

PubMed Central

2011-01-01

Background Poly(ADP-ribose) polymerase is evolutionarily conserved as a responder to various forms of stress. Though PARP's role in cell death is well addressed, its role in development and multicellularity is still an enigma. We have previously reported the role of PARP in oxidative stress induced delayed development of D. discoideum. Results In the current study we highlight the involvement of PARP during D. discoideum development. Oxidative stress affects expression of aca and cAR1 thus affecting aggregation. Although parp expression is not affected during oxidative stress but it is involved during normal development as confirmed by our PARP down-regulation studies. Constitutive PARP down-regulation resulted in blocked development while no effect was observed on D. discoideum growth. Interestingly, stage specific PARP down-regulation arrested development at the slug stage. Conclusion These results emphasize that PARP is essential for complex differentiation and its function may be linked to multicellularity. This is the first report where the involvement of PARP during normal multicellular development in D. discoideum, an ancient eukaryote, is established which could be of evolutionary significance. Thus our study adds one more role to the multitasking function of PARP. PMID:21385463

Spdef Null Mice Lack Conjunctival Goblet Cells and Provide a Model of Dry Eye

PubMed Central

Marko, Christina K.; Menon, Balaraj B.; Chen, Gang; Whitsett, Jeffrey A.; Clevers, Hans; Gipson, Ilene K.

2014-01-01

Goblet cell numbers decrease within the conjunctival epithelium in drying and cicatrizing ocular surface diseases. Factors regulating goblet cell differentiation in conjunctival epithelium are unknown. Recent data indicate that the transcription factor SAM-pointed domain epithelial-specific transcription factor (Spdef) is essential for goblet cell differentiation in tracheobronchial and gastrointestinal epithelium of mice. Using Spdef−/− mice, we determined that Spdef is required for conjunctival goblet cell differentiation and that Spdef−/− mice, which lack conjunctival goblet cells, have significantly increased corneal surface fluorescein staining and tear volume, a phenotype consistent with dry eye. Microarray analysis of conjunctival epithelium in Spdef−/− mice revealed down-regulation of goblet cell–specific genes (Muc5ac, Tff1, Gcnt3). Up-regulated genes included epithelial cell differentiation/keratinization genes (Sprr2h, Tgm1) and proinflammatory genes (Il1-α, Il-1β, Tnf-α), all of which are up-regulated in dry eye. Interestingly, four Wnt pathway genes were down-regulated. SPDEF expression was significantly decreased in the conjunctival epithelium of Sjögren syndrome patients with dry eye and decreased goblet cell mucin expression. These data demonstrate that Spdef is required for conjunctival goblet cell differentiation and down-regulation of SPDEF may play a role in human dry eye with goblet cell loss. Spdef−/− mice have an ocular surface phenotype similar to that in moderate dry eye, providing a new, more convenient model for the disease. PMID:23665202

Spdef null mice lack conjunctival goblet cells and provide a model of dry eye.

PubMed

Marko, Christina K; Menon, Balaraj B; Chen, Gang; Whitsett, Jeffrey A; Clevers, Hans; Gipson, Ilene K

2013-07-01

Goblet cell numbers decrease within the conjunctival epithelium in drying and cicatrizing ocular surface diseases. Factors regulating goblet cell differentiation in conjunctival epithelium are unknown. Recent data indicate that the transcription factor SAM-pointed domain epithelial-specific transcription factor (Spdef) is essential for goblet cell differentiation in tracheobronchial and gastrointestinal epithelium of mice. Using Spdef(-/-) mice, we determined that Spdef is required for conjunctival goblet cell differentiation and that Spdef(-/-) mice, which lack conjunctival goblet cells, have significantly increased corneal surface fluorescein staining and tear volume, a phenotype consistent with dry eye. Microarray analysis of conjunctival epithelium in Spdef(-/-) mice revealed down-regulation of goblet cell-specific genes (Muc5ac, Tff1, Gcnt3). Up-regulated genes included epithelial cell differentiation/keratinization genes (Sprr2h, Tgm1) and proinflammatory genes (Il1-α, Il-1β, Tnf-α), all of which are up-regulated in dry eye. Interestingly, four Wnt pathway genes were down-regulated. SPDEF expression was significantly decreased in the conjunctival epithelium of Sjögren syndrome patients with dry eye and decreased goblet cell mucin expression. These data demonstrate that Spdef is required for conjunctival goblet cell differentiation and down-regulation of SPDEF may play a role in human dry eye with goblet cell loss. Spdef(-/-) mice have an ocular surface phenotype similar to that in moderate dry eye, providing a new, more convenient model for the disease. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

The human GINS complex associates with Cdc45 and MCM and is essential for DNA replication

PubMed Central

Aparicio, Tomás; Guillou, Emmanuelle; Coloma, Javier; Montoya, Guillermo; Méndez, Juan

2009-01-01

The GINS complex, originally discovered in Saccharomyces cerevisiae and Xenopus laevis, binds to DNA replication origins shortly before the onset of S phase and travels with the replication forks after initiation. In this study we present a detailed characterization of the human GINS (hGINS) homolog. Using new antibodies that allow the detection of endogenous hGINS in cells and tissues, we have examined its expression, abundance, subcellular localization and association with other DNA replication proteins. Expression of hGINS is restricted to actively proliferating cells. During the S phase, hGINS becomes part of a Cdc45–MCM–GINS (CMG) complex that is assembled on chromatin. Down-regulation of hGINS destabilizes CMG, causes a G1–S arrest and slows down ongoing DNA replication, effectively blocking cell proliferation. Our data support the notion that hGINS is an essential component of the human replisome. PMID:19223333

Marked improvement of thrombocytopenia in a murine model of idiopathic thrombocytopenic purpura by pegylated recombinant human megakaryocyte growth and development factor.

PubMed

Shibuya, Kazunori; Kuwaki, Tomoaki; Tahara, Emiko; Yuki, Chizuru; Akahori, Hiromichi; Kato, Takashi; Miyazaki, Hiroshi

2002-10-01

We examined the stimulatory effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production in male (NZW x BXSB) F(l) (W/B F(1)) mice, a murine model of idiopathic thrombocytopenic purpura. A cohort of 19- to 25-week-old, severely thrombocytopenic male W/B F(1) mice were given PEG-rHuMGDF at different dosing schedules. Before and at various times after therapy, platelet counts, reticulated platelets, platelet lifespan, and levels of platelet-associated immunoglobulin G were measured. Analysis of megakaryocytic cells was performed. Treatment of male W/B F(1) mice with PEG-rHuMGDF (30 microg/kg/day) three times per week for several weeks resulted in sustained thrombocytosis, accompanied by increased megakaryocytopoiesis in both the bone marrow and spleen. The degree of the platelet response to PEG-rHuMGDF varied between individual mice, likely reflecting the heterogeneity of the disease. Production of new platelets in response to PEG-rHuMGDF was manifested by an increase in reticulated platelets. Levels of platelet-associated immunoglobulin G decreased inversely during periods of thrombocytosis. PEG-rHuMGDF therapy also improved thrombocytopenia in male W/B F(1) mice refractory to splenectomy. Platelet lifespan was not affected by PEG-rHuMGDF. Male W/B F(1) mice treated with pegylated murine MGDF, a homologue of PEG-rHuMGDF, had persistent thrombocytosis for at least 7 months, suggesting that antiplatelet antibody production was not enhanced. PEG-rHuMGDF therapy potently stimulated platelet production, effectively ameliorating thrombocytopenia in a murine model of idiopathic thrombocytopenic purpura.

The essential aspect in sewerage regulation in Indonesia

NASA Astrophysics Data System (ADS)

Siami, L.

2018-01-01

Several cities in Indonesia have the sewerage local regulation such as Banjarmasin, Bantul, Surakarta and Denpasar. Meanwhile, The National Government have guideline in composing domestic sewerage regulation. Each city have their own characteristic and issues that need to be carried out by the local regulation. By using SWOT analysis, this study tries to figure out several aspect that need to be included in the local regulation. International references from developed and developing countries like Japan, Phillipines, Malaysia and Thailand were also used as benchmark without neglecting the local conditions of cities in Indonesia. Several crucial aspect of local regulation are institutional authority, composition on-site and off-site system, tariff, evaluation and monitoring, as well as punishment and rewards. Both tariff and evaluation aspects need to be narrowed down into specific regulations.

JAK2 mutations and clinical practice in myeloproliferative neoplasms.

PubMed

Tefferi, Ayalew

2007-01-01

With the discovery in the last 3 years of novel Janus kinase 2 (JAK2) and thrombopoietin receptor (MPL) mutations, the pathogenetic understanding of and clinical practice for myeloproliferative neoplasms (MPNs) have entered a new era. Each one of these newly discovered mutations, including JAK2V617F, MPLW515L, and a JAK2 exon 12 mutation, has been shown to result in constitutive activation of JAK-STAT signaling and also induce a MPN phenotype in mice. Thus, JAK2 is now considered to be a legitimate target for drug development in MPNs, and small molecule JAK2 inhibitors have already gone through successful preclinical testing, and early-phase human trials in primary myelofibrosis have already begun. Furthermore, JAK2 mutation screening has now become a front-line diagnostic test in the evaluation of both "erythrocytosis" and thrombocytosis and the 2001 World Health Organization diagnostic criteria for polycythemia vera, essential thrombocythemia, and primary myelofibrosis have now been revised to incorporate JAK2V617F mutation screening.

Mechanisms of mutations in myeloproliferative neoplasms.

PubMed

Levine, Ross L

2009-12-01

In recent years, a series of studies have provided genetic insight into the pathogenesis of myeloproliferative neoplasms (MPNs). It is now known that JAK2V617F mutations are present in 90% of patients with polycythaemia vera (PV), 60% of patients with essential thrombocytosis (ET) and 50% of patients with myelofibrosis (MF). Despite the high prevalence of JAK2V617F mutations in these three myeloid malignancies, several questions remain. For example, how does one mutation contribute to the pathogenesis of three clinically distinct diseases, and how do some patients develop these diseases in the absence of a JAK2V617F mutation? Single nucleotide polymorphisms at various loci and somatic mutations, such as those in MPLW515L/K, TET2 and in exon 12 of JAK2, may also contribute to the pathogenesis of these MPNs. There are likely additional germline and somatic genetic factors important to the MPN phenotype. Additional studies of large MPN and control cohorts with new techniques will help identify these factors.

Beadex Function in the Motor Neurons Is Essential for Female Reproduction in Drosophila melanogaster

PubMed Central

Kairamkonda, Subhash; Nongthomba, Upendra

2014-01-01

Drosophila melanogaster has served as an excellent model system for understanding the neuronal circuits and molecular mechanisms regulating complex behaviors. The Drosophila female reproductive circuits, in particular, are well studied and can be used as a tool to understand the role of novel genes in neuronal function in general and female reproduction in particular. In the present study, the role of Beadex, a transcription co-activator, in Drosophila female reproduction was assessed by generation of mutant and knock down studies. Null allele of Beadex was generated by transposase induced excision of P-element present within an intron of Beadex gene. The mutant showed highly compromised reproductive abilities as evaluated by reduced fecundity and fertility, abnormal oviposition and more importantly, the failure of sperm release from storage organs. However, no defect was found in the overall ovariole development. Tissue specific, targeted knock down of Beadex indicated that its function in neurons is important for efficient female reproduction, since its neuronal knock down led to compromised female reproductive abilities, similar to Beadex null females. Further, different neuronal class specific knock down studies revealed that Beadex function is required in motor neurons for normal fecundity and fertility of females. Thus, the present study attributes a novel and essential role for Beadex in female reproduction through neurons. PMID:25396431

Regulation of occupational health and safety in the semiconductor industry: enforcement problems and solutions.

PubMed

Watterson, Andrew

2006-01-01

Reports of high incidences of occupational illnesses in the semiconductor industry should have triggered global investigations and rigorous inspection of the industry. Yet semiconductor plants remain essentially unregulated. Health and safety standards are inadequate and enforcement is lax. Roles for stakeholders in laying down good practice, monitoring, and regulating are proposed, and obstacles are described. Effective regulation has advantages for the industry as well as workers. Conditions for best practice include education at all levels, protection and support for labor inspectors, government commitment to enforcing laws, recognition of the right of workers to organize, and recognition of their rights.

Mechanisms of Organophosphorus (OP) Injury: Sarin-Induced Hippocampal Gene Expression Changes and Pathway Perturbation

DTIC Science & Technology

2012-01-01

components of the endomembrane system, including endoplasmic reticulum (ER) and Golgi apparatus were significantly down-regulated. As a result of...impairment in dopaminergic functions (Lucot JB, personal communication). Interestingly, data on sarin exposures have shown inhibition of new memory...quite unexpected that the endoplasmic reticulum (ER) and Golgi apparatus , the subcellular organelles essential for processing (e.g., folding, post

Pinus densiflora leaf essential oil induces apoptosis via ROS generation and activation of caspases in YD-8 human oral cancer cells

PubMed Central

JO, JEONG-RANG; PARK, JU SUNG; PARK, YU-KYOUNG; CHAE, YOUNG ZOO; LEE, GYU-HEE; PARK, GY-YOUNG; JANG, BYEONG-CHURL

2012-01-01

The leaf of Pinus (P.) densiflora, a pine tree widely distributed in Asian countries, has been used as a traditional medicine. In the present study, we investigated the anticancer activity of essential oil, extracted by steam distillation, from the leaf of P. densiflora in YD-8 human oral squamous cell carcinoma (OSCC) cells. Treatment of YD-8 cells with P. densiflora leaf essential oil (PLEO) at 60 μg/ml for 8 h strongly inhibited proliferation and survival and induced apoptosis. Notably, treatment with PLEO led to generation of ROS, activation of caspase-9, PARP cleavage, down-regulation of Bcl-2, and phosphorylation of ERK-1/2 and JNK-1/2 in YD-8 cells. Treatment with PLEO, however, did not affect the expression of Bax, XIAP and GRP78. Importantly, pharmacological inhibition studies demonstrated that treatment with vitamin E (an anti-oxidant) or z-VAD-fmk (a pan-caspase inhibitor), but not with PD98059 (an ERK-1/2 inhibitor) or SP600125 (a JNK-1/2 inhibitor), strongly suppressed PLEO-induced apoptosis in YD-8 cells and reduction of their survival. Vitamin E treatment further blocked activation of caspase-9 and Bcl-2 down-regulation induced by PLEO. Thus, these results demonstrate firstly that PLEO has anti-proliferative, anti-survival and pro-apoptotic effects on YD-8 cells and the effects are largely due to the ROS-dependent activation of caspases. PMID:22086183

Pinus densiflora leaf essential oil induces apoptosis via ROS generation and activation of caspases in YD-8 human oral cancer cells.

PubMed

Jo, Jeong-Rang; Park, Ju Sung; Park, Yu-Kyoung; Chae, Young Zoo; Lee, Gyu-Hee; Park, Gy-Young; Jang, Byeong-Churl

2012-04-01

The leaf of Pinus (P.) densiflora, a pine tree widely distributed in Asian countries, has been used as a traditional medicine. In the present study, we investigated the anticancer activity of essential oil, extracted by steam distillation, from the leaf of P. densiflora in YD-8 human oral squamous cell carcinoma (OSCC) cells. Treatment of YD-8 cells with P. densiflora leaf essential oil (PLEO) at 60 µg/ml for 8 h strongly inhibited proliferation and survival and induced apoptosis. Notably, treatment with PLEO led to generation of ROS, activation of caspase-9, PARP cleavage, down-regulation of Bcl-2, and phosphorylation of ERK-1/2 and JNK-1/2 in YD-8 cells. Treatment with PLEO, however, did not affect the expression of Bax, XIAP and GRP78. Importantly, pharmaco-logical inhibition studies demonstrated that treatment with vitamin E (an anti-oxidant) or z-VAD-fmk (a pan-caspase inhibitor), but not with PD98059 (an ERK-1/2 inhibitor) or SP600125 (a JNK-1/2 inhibitor), strongly suppressed PLEO-induced apoptosis in YD-8 cells and reduction of their survival. Vitamin E treatment further blocked activation of caspase-9 and Bcl-2 down-regulation induced by PLEO. Thus, these results demonstrate firstly that PLEO has anti-proliferative, anti-survival and pro-apoptotic effects on YD-8 cells and the effects are largely due to the ROS-dependent activation of caspases.

Study of traits and recalcitrance reduction of field-grown COMT down-regulated switchgrass

DOE PAGES

Li, Mi; Pu, Yunqiao; Yoo, Chang Geun; ...

2017-01-03

The native recalcitrance of plants hinders the biomass conversion process using current biorefinery techniques. Down-regulation of the caffeic acid O-methyltransferase (COMT) gene in the lignin biosynthesis pathway of switchgrass reduced the thermochemical and biochemical conversion recalcitrance of biomass. Due to potential environmental influences on lignin biosynthesis and deposition, studying the consequences of physicochemical changes in field-grown plants without pretreatment is essential to evaluate the performance of lignin-altered plants. In this study, we determined the chemical composition, cellulose crystallinity and the degree of its polymerization, molecular weight of hemicellulose, and cellulose accessibility of cell walls in order to better understand themore » fundamental features of why biomass is recalcitrant to conversion without pretreatment. The most important is to investigate whether traits and features are stable in the dynamics of field environmental effects over multiple years.« less

PRMT5 is essential for the eIF4E-mediated 5′-cap dependent translation

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

Lim, Ji-Hong; Lee, Yoon-Mi; Lee, Gibok

2014-10-03

Highlights: • PRMT5 participates in syntheses of HIF-1α, c-Myc and cyclin D1 proteins. • PRMT5 promotes the 5′-cap dependent translation. • PRMT5 is required for eIF4E binding to mRNA 5′-cap. • PRMT5 is essential for eIF4E-dependent cell proliferation. - Abstract: It is becoming clear that PRMT5 plays essential roles in cell cycle progression, survival, and responses to external stresses. However, the precise mechanisms underlying such roles of PRMT5 have not been clearly understood. Previously, we have demonstrated that PRMT5 participates in cellular adaptation to hypoxia by ensuring 5′-cap dependent translation of HIF-1α. Given that c-Myc and cyclin D1 expressions aremore » also tightly regulated in 5′-cap dependent manner, we here tested the possibility that PRMT5 promotes cell proliferation by increasing de novo syntheses of the oncoproteins. c-Myc and cyclin D1 were found to be noticeably downregulated by PRMT5 knock-down. A RNA immunoprecipitation analysis, which can identify RNA–protein interactions, showed that PRMT5 is required for the interaction among eIF4E and 5′-UTRs of HIF-1α, c-Myc and cyclin D1 mRNAs. In addition, PRMT5 knock-down inhibited cell proliferation by inducing cell cycle arrest at the G1 phase. More importantly, ectopic expression of eIF4E significantly rescued the cell cycle progression and cell proliferation even in PRMT5-deficeint condition. Based on these results, we propose that PRMT5 determines cell fate by regulating 5′-cap dependent translation of proteins essential for proliferation and survival.« less

Gene Repression in Haloarchaea Using the CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-Cas I-B System.

PubMed

Stachler, Aris-Edda; Marchfelder, Anita

2016-07-15

The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system is used by bacteria and archaea to fend off foreign genetic elements. Since its discovery it has been developed into numerous applications like genome editing and regulation of transcription in eukaryotes and bacteria. For archaea currently no tools for transcriptional repression exist. Because molecular biology analyses in archaea become more and more widespread such a tool is vital for investigating the biological function of essential genes in archaea. Here we use the model archaeon Haloferax volcanii to demonstrate that its endogenous CRISPR-Cas system I-B can be harnessed to repress gene expression in archaea. Deletion of cas3 and cas6b genes results in efficient repression of transcription. crRNAs targeting the promoter region reduced transcript levels down to 8%. crRNAs targeting the reading frame have only slight impact on transcription. crRNAs that target the coding strand repress expression only down to 88%, whereas crRNAs targeting the template strand repress expression down to 8%. Repression of an essential gene results in reduction of transcription levels down to 22%. Targeting efficiencies can be enhanced by expressing a catalytically inactive Cas3 mutant. Genes can be targeted on plasmids or on the chromosome, they can be monocistronic or part of a polycistronic operon. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Gene Repression in Haloarchaea Using the CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-Cas I-B System*

PubMed Central

Stachler, Aris-Edda; Marchfelder, Anita

2016-01-01

The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system is used by bacteria and archaea to fend off foreign genetic elements. Since its discovery it has been developed into numerous applications like genome editing and regulation of transcription in eukaryotes and bacteria. For archaea currently no tools for transcriptional repression exist. Because molecular biology analyses in archaea become more and more widespread such a tool is vital for investigating the biological function of essential genes in archaea. Here we use the model archaeon Haloferax volcanii to demonstrate that its endogenous CRISPR-Cas system I-B can be harnessed to repress gene expression in archaea. Deletion of cas3 and cas6b genes results in efficient repression of transcription. crRNAs targeting the promoter region reduced transcript levels down to 8%. crRNAs targeting the reading frame have only slight impact on transcription. crRNAs that target the coding strand repress expression only down to 88%, whereas crRNAs targeting the template strand repress expression down to 8%. Repression of an essential gene results in reduction of transcription levels down to 22%. Targeting efficiencies can be enhanced by expressing a catalytically inactive Cas3 mutant. Genes can be targeted on plasmids or on the chromosome, they can be monocistronic or part of a polycistronic operon. PMID:27226589

Human a-L-fucosidase-1 attenuates the invasive properties of thyroid cancer.

PubMed

Vecchio, Giancarlo; Parascandolo, Alessia; Allocca, Chiara; Ugolini, Clara; Basolo, Fulvio; Moracci, Marco; Strazzulli, Andrea; Cobucci-Ponzano, Beatrice; Laukkanen, Mikko O; Castellone, Maria Domenica; Tsuchida, Nobuo

2017-04-18

Glycans containing α-L-fucose participate in diverse interactions between cells and extracellular matrix. High glycan expression on cell surface is often associated with neoplastic progression. The lysosomal exoenzyme, α-L-fucosidase-1 (FUCA-1) removes fucose residues from glycans. The FUCA-1 gene is down-regulated in highly aggressive and metastatic human tumors. However, the role of FUCA-1 in tumor progression remains unclear. It is speculated that its inactivation perturbs glycosylation of proteins involved in cell adhesion and promotes cancer. FUCA-1 expression of various thyroid normal and cancer tissues assayed by immunohistochemical (IHC) staining was high in normal thyroids and papillary thyroid carcinomas (PTC), whereas it progressively decreased in poorly differentiated, metastatic and anaplastic thyroid carcinomas (ATC). FUCA-1 mRNA expression from tissue samples and cell lines and protein expression levels and enzyme activity in thyroid cancer cell lines paralleled those of IHC staining. Furthermore, ATC-derived 8505C cells adhesion to human E-selectin and HUVEC cells was inhibited by bovine α-L-fucosidase or Lewis antigens, thus pointing to an essential role of fucose residues in the adhesive phenotype of this cancer cell line. Finally, 8505C cells transfected with a FUCA-1 containing plasmid displayed a less invasive phenotype versus the parental 8505C. These results demonstrate that FUCA-1 is down-regulated in ATC compared to PTC and normal thyroid tissues and cell lines. As shown for other human cancers, the down-regulation of FUCA-1 correlates with increased aggressiveness of the cancer type. This is the first report indicating that the down-regulation of FUCA-1 is related to the increased aggressiveness of thyroid cancer.

Calreticulin Induces Dilated Cardiomyopathy

PubMed Central

Lee, Dukgyu; Oka, Tatsujiro; Hunter, Beth; Robinson, Alison; Papp, Sylvia; Nakamura, Kimitoshi; Srisakuldee, Wattamon; Nickel, Barbara E.; Light, Peter E.; Dyck, Jason R. B.; Lopaschuk, Gary D.; Kardami, Elissavet; Opas, Michal; Michalak, Marek

2013-01-01

Background Calreticulin, a Ca2+-buffering chaperone of the endoplasmic reticulum, is highly expressed in the embryonic heart and is essential for cardiac development. After birth, the calreticulin gene is sharply down regulated in the heart, and thus, adult hearts have negligible levels of calreticulin. In this study we tested the role of calreticulin in the adult heart. Methodology/Principal Findings We generated an inducible transgenic mouse in which calreticulin is targeted to the cardiac tissue using a Cre/loxP system and can be up-regulated in adult hearts. Echocardiography analysis of hearts from transgenic mice expressing calreticulin revealed impaired left ventricular systolic and diastolic function and impaired mitral valve function. There was altered expression of Ca2+ signaling molecules and the gap junction proteins, Connexin 43 and 45. Sarcoplasmic reticulum associated Ca2+-handling proteins (including the cardiac ryanodine receptor, sarco/endoplasmic reticulum Ca2+-ATPase, and cardiac calsequestrin) were down-regulated in the transgenic hearts with increased expression of calreticulin. Conclusions/Significance We show that in adult heart, up-regulated expression of calreticulin induces cardiomyopathy in vivo leading to heart failure. This is due to an alternation in changes in a subset of Ca2+ handling genes, gap junction components and left ventricle remodeling. PMID:23437120

p65 down-regulates DEPTOR expression in response to LPS stimulation in hepatocytes.

PubMed

Yu, Xiaoling; Jin, Dan; Yu, An; Sun, Jun; Chen, Xiaodong; Yang, Zaiqing

2016-09-01

DEPTOR, a novel endogenous inhibitor of mTOR, plays an important role in regulating the inflammatory response in vascular endothelial cells (ECs) and in mouse skeletal muscle. However, the regulatory mechanism of DEPTOR transcription and its effects on liver inflammation are unknown presently. Here we reported the role of DEPTOR in regulating inflammatory response in mouse liver-derived Hepa1-6 cells and in a mouse model with LPS-induced hepatic inflammation. The results revealed that DEPTOR over-expression in Hepa1-6 liver cells increased the mRNA levels of the pro-inflammatory cytokines interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1). Contrasting results were observed in Hepa1-6 cells with DEPTOR interference. Treatment Hepa1-6 cells with rapamycin, a specific inhibitor of mTORC1, increased MCP-1 mRNA, but have no significant effect on IL-6 mRNA. DEPTOR expression was down-regulated in Hepa1-6 cells with the treatment of inflammatory stimuli LPS or the over-expression of p65/NF-κB, a key inflammatory transcription factor. NF-κB antagonist (PDTC) and inhibitor (IκBα) blocked the effect of LPS on DEPTOR expression. The study in vivo showed that DEPTOR mRNA and protein were significantly reduced in a mouse model with LPS-induced hepatic inflammation, which was accompanied by a concurrent activation of the mTOR signaling pathway. Further, the transcriptional regulation of DEPTOR was explored, which revealed that DEPTOR promoter activity was significantly down-regulated by NF-κB. The progressive deletions and mutations demonstrated that the NF-κB binding motif situated at -145/-127 region is an essential component required for the DEPTOR promoter activity. Chromatin immunoprecipitation (ChIP) assays determined that p65 can directly interact with the DEPTOR promoter DNA. Those results indicate DEPTOR regulates liver inflammation at least partially via mTORC1 pathway, and is down-regulated by LPS through p65. Copyright © 2016 Elsevier B.V. All rights reserved.

The in vitro study of apoptosis in NB4 cell induced by citral.

PubMed

Xia, Hailong; Liang, Wei; Song, Qin; Chen, Xiaowen; Chen, Xin; Hong, Jian

2013-01-01

Citral, 3,7-dimethyl-2,6-octadienal, is a key component of the essential oils extracted from several lemon-scented herbal plants. Besides its antifungal activity, the anticancer effect of citral was studied in recent years. In this study, we investigated the effect of citral on the acute promyelocytic leukemia cell line NB4. Citral treatment had an antiproliferative effect in NB4 cells via the induction of apoptosis assessed by morphology, proliferation assay, DNA electrophoresis, Annexin V-FITC/PI staining and caspase-3 activation. And citral induced apoptosis of NB4 cells in a dose- and time-dependent manner. In addition, citral treatment induced decreased mitochondrial membrane potential, indicating that citral induced apoptosis via the mitochondrial pathway. Bax up-regulation and Bcl-2 down-regulation on mRNA level and NF-κB down-regulation on protein level was found in this study, suggesting that Bcl-2, Bax and NF-κB may be involved in the mechanism of the apoptotic effect of citral on NB4 cells. These data suggest that citral has a potential therapeutic effect on leukemia.

PDGF-AA promotes osteogenic differentiation and migration of mesenchymal stem cell by down-regulating PDGFRα and derepressing BMP-Smad1/5/8 signaling.

PubMed

Li, Anna; Xia, Xuechun; Yeh, James; Kua, Huiyi; Liu, Huijuan; Mishina, Yuji; Hao, Aijun; Li, Baojie

2014-01-01

Platelet-derived growth factors (PDGFs) play important roles in skeletal development and bone fracture healing, yet how PDGFs execute their functions remains incompletely understood. Here we show that PDGF-AA, but not -AB or -BB, could activate the BMP-Smad1/5/8 pathway in mesenchymal stem cells (MSCs), which requires BMPRIA as well as PDGFRα. PDGF-AA promotes MSC osteogenic differentiation through the BMP-Smad1/5/8-Runx2/Osx axis and MSC migration via the BMP-Smad1/5/8-Twist1/Atf4 axis. Mechanistic studies show that PDGF-AA activates BMP-Smad1/5/8 signaling by feedback down-regulating PDGFRα, which frees BMPRI and allows for BMPRI-BMPRII complex formation to activate smad1/5/8, using BMP molecules in the microenvironment. This study unravels a physical and functional interaction between PDGFRα and BMPRI, which plays an important role in MSC differentiation and migration, and establishes a link between PDGF-AA and BMPs pathways, two essential regulators of embryonic development and tissue homeostasis.

c-Myc plays a key role in TADs-induced apoptosis and cell cycle arrest in human hepatocellular carcinoma cells.

PubMed

Zhang, Dongdong; Qi, Junpeng; Liu, Rui; Dai, Bingling; Ma, Weina; Zhan, Yingzhuan; Zhang, Yanmin

2015-01-01

Cancer cell growth is complicated progression which is regulated and controlled by multiple factors including cell cycle, migration and apoptosis. In present study, we report that TADs, a novel derivative of taspine, has an essential role in resisting hepatocellular carcinoma growth (including arrest cell cycle) and migration, and inducing cell apoptosis. Our findings demonstrated that the TADs showed good inhibition on the hepatoma cell growth and migration, and good action on apoptosis induction. Using genome-wide microarray analysis, we found the down-regulated growth and apoptosis factors, and selected down-regulated genes were confirmed by Western blot. Knockdown of a checkpoint c-Myc by siRNA significantly attenuated tumor inhibition and apoptosis effects of TADs. Moreover, our results indicated TADs could simultaneously increase cyclin D1 protein levels and decrease amount of cyclin E, cyclin B1 and cdc2 of the cycle proteins, and also TADs reduced Bcl-2 expression, and upregulated Bad, Bak and Bax activities. In conclusion, these results illustrated that TADs is a key factor in growth and apoptosis signaling inhibitor, has potential in cancer therapy.

Cultured bovine granulosa cells rapidly lose important features of their identity and functionality but partially recover under long-term culture conditions.

PubMed

Yenuganti, Vengala Rao; Vanselow, Jens

2017-05-01

Cell culture models are essential for the detailed study of molecular processes. We analyze the dynamics of changes in a culture model of bovine granulosa cells. The cells were cultured for up to 8 days and analyzed for steroid production and gene expression. According to the expression of the marker genes CDH1, CDH2 and VIM, the cells maintained their mesenchymal character throughout the time of culture. In contrast, the levels of functionally important transcripts and of estradiol and progesterone production were rapidly down-regulated but showed a substantial up-regulation from day 4. FOXL2, a marker for granulosa cell identity, was also rapidly down-regulated after plating but completely recovered towards the end of culture. In contrast, expression of the Sertoli cell marker SOX9 and the lesion/inflammation marker PTGS2 increased during the first 2 days after plating but gradually decreased later on. We conclude that only long-term culture conditions (>4 days) allow the cells to recover from plating stress and to re-acquire characteristic granulosa cell features.

The microRNA-processing enzyme Dicer is essential for thyroid function.

PubMed

Frezzetti, Daniela; Reale, Carla; Calì, Gaetano; Nitsch, Lucio; Fagman, Henrik; Nilsson, Ola; Scarfò, Marzia; De Vita, Gabriella; Di Lauro, Roberto

2011-01-01

Dicer is a type III ribonuclease required for the biogenesis of microRNAs (miRNAs), a class of small non-coding RNAs regulating gene expression at the post-transcriptional level. To explore the functional role of miRNAs in thyroid gland function, we generated a thyrocyte-specific Dicer conditional knockout mouse. Here we show that development and early differentiation of the thyroid gland are not affected by the absence of Dicer, while severe hypothyroidism gradually develops after birth, leading to reduced body weight and shortened life span. Histological and molecular characterization of knockout mice reveals a dramatic loss of the thyroid gland follicular architecture associated with functional aberrations and down-regulation of several differentiation markers. The data presented in this study show for the first time that an intact miRNAs processing machinery is essential for thyroid physiology, suggesting that deregulation of specific miRNAs could be also involved in human thyroid dysfunctions.

Transcriptome profiling and cataloging differential gene expression in floral buds of fertile and sterile lines of cotton (Gossypium hirsutum L.).

PubMed

Hamid, Rasmieh; Tomar, Rukam S; Marashi, Hassan; Shafaroudi, Saeid Malekzadeh; Golakiya, Balaji A; Mohsenpour, Motahhareh

2018-06-20

Cytoplasmic Male Sterility is maternally inherited trait in plants, characterized by failure to produce functional pollen during anther development. Anther development is modulated through the interaction of nuclear and mitochondrial genes. In the present study, differential gene expression of floral buds at the sporogenous stage (SS) and microsporocyte stage (MS) between CGMS and its fertile maintainer line of cotton plants was studied. A total of 320 significantly differentially expressed genes, including 20 down-regulated and 37 up-regulated in CGMS comparing with its maintainer line at the SS stage, as well as and 89 down-regulated and 4 up-regulated in CGMS compared to the fertile line at MS stage. Comparing the two stages in the same line, there were 6 down-regulated differentially expressed genes only induced in CGMS and 9 up-regulated differentially expressed gene only induced in its maintainer. GO analysis revealed essential genes responsible for pollen development, and cytoskeleton category show differential expression between the fertile and CGMS lines. Validation studies by qRT-PCR shows concordance with RNA-seq result. A set of novel SSRs identified in this study can be used in evaluating genetic relationships among cultivars, QTL mapping, and marker-assisted breeding. We reported aberrant expression of genes related to pollen exine formation, and synthesis of pectin lyase, myosine heavy chain, tubulin, actin-beta, heat shock protein and myeloblastosis (MYB) protein as targets for CMS in cotton. The results of this study contribute to basic information for future screening of genes and identification of molecular portraits responsible for CMS as well as to elucidate molecular mechanisms that lead to CMS in cotton. Copyright © 2018 Elsevier B.V. All rights reserved.

Role of miR-452-5p in the tumorigenesis of prostate cancer: A study based on the Cancer Genome Atl(TCGA), Gene Expression Omnibus (GEO), and bioinformatics analysis.

PubMed

Gao, Li; Zhang, Li-Jie; Li, Sheng-Hua; Wei, Li-Li; Luo, Bin; He, Rong-Quan; Xia, Shuang

2018-03-06

MiR-452-5p has been reported to be down-regulated in prostate cancer, affecting the development of this type of cancer. However, the molecular mechanism of miR-452-5p in prostate cancer remains unclear. Therefore, we investigated the network of target genes of miR-452-5p in prostate cancer using bioinformatics analyses. We first analyzed the expression profiles and prognostic value of miR-452-5p in prostate cancer tissues from a public database. Gene Ontology (GO), the Kyoto Encyclopedia of Genes and Genomes (KEGG), PANTHER pathway analyses, and a disease ontology (DG) analysis were performed to find the molecular functions of the target genes from GSE datasets and miRWalk. Finally, we validated hub genes from the protein-protein interaction (PPI) networks of the target genes in the Human Protein Atlas (HPA) database and Gene Expression Profiling Interactive Analysis (GEPIA). Narrowing down the optimal target genes was conducted by seeking the common parts of up-regulated genes from GEPIA, down-regulated genes from GSE datasets, and predicted genes in miRWalk. Based on mining of GEO and ArrayExpress microarray chips and miRNA-Seq data in the TCGA database, which includes 1007 prostate cancer samples and 387 non-cancer samples, miR-452-5p is shown to be down-regulated in prostate cancer. GO, KEGG, and PANTHER pathway analyses suggested that the target genes might participate in important biological processes, such as transforming growth factor beta signaling and the positive regulation of brown fat cell differentiation and mesenchymal cell differentiation, as well as the Ras signaling pathway and pathways regulating the pluripotency of stem cells and arrhythmogenic right ventricular cardiomyopathy (ARVC). Nine genes-GABBR, PNISR, NTSR1, DOCK1, EREG, SFRP1, PTGS2, LEF1, and BMP2-were defined as hub genes in the PPI network. Three genes-FAM174B, SLC30A4, and SLIT1-were jointly shared by GEPIA, the GSE datasets, and miRWalk. Down-regulated miR-452-5p might play an essential role in the tumorigenesis of prostate cancer. Copyright © 2018. Published by Elsevier GmbH.

[The occurrence and impact on survival of type 2 diabetes mellitus and thrombocytosis in colorectal cancer, before and after the surgical resection of the primary tumor].

PubMed

Herold, Zoltán; Ambrus, Viktória; Herold, Magdolna; Herczeg, György; Igaz, Péter; Harsányi, László; Somogyi, Anikó

2018-05-01

The relationship between platelets and metastatic tumor cells is an ongoing research area. Pre- and postoperative thrombocytosis are suggested predictive survival markers. Colorectal cancer and type 2 diabetes are characterized by various changes to platelets. The occurrence of colorectal cancer is more frequent in diabetes. Our aim was to determine the occurrence of type 2 diabetes in colorectal cancer patients, who attended the Semmelweis University 2nd Department of Internal Medicine's Oncology Department in the last three years. Further goals included the evaluation of anamnestic, pre- and postoperative laboratory data, and whether diabetes can be a significant survival factor. A retrospective study was conducted with 86 randomly selected colorectal cancer patients' preoperative (86 patients) and paired postoperative (66, who were operable) data. Patients were monitored no later than September 30, 2017 or until their death. Preoperatively, elevated (over 400 Giga/L) platelet counts were present in 22.1% of the patients (323.5 ± 128.63 Giga/L, mean ± SD) which decreased to 10.6% postoperatively (χ 2 : p = 0.0351; 289.2 ± 82.45 Giga/L, p = 0.0232). Negative correlation was found between platelet counts and overall survival (R: -0.35, p = 0.0085). One third of the patients had diabetes. Laboratory results (i.e., blood counts, creatinine) between diabetic and non-diabetic patients were not significant. Diabetes is a significant five-fold postoperative risk factor for shorter overall survival (relative risk: 5.1612, p = 0.0165). Average survival was 30.6 ± 26.78 months. Persistent consequential postoperative thrombocytosis may indicate shorter survival time. Our observations suggest elevated platelet counts and type 2 diabetes as prognostic markers for survival at the recognition of colorectal tumors. Orv Hetil. 2018; 159(19): 756-767.

Necessity of angiotensin-converting enzyme-related gene for cardiac functions and longevity of Drosophila melanogaster assessed by optical coherence tomography

NASA Astrophysics Data System (ADS)

Liao, Fang-Tsu; Chang, Cheng-Yi; Su, Ming-Tsan; Kuo, Wen-Chuan

2014-01-01

Prior studies have established the necessity of an angiotensin-converting enzyme-related (ACER) gene for heart morphogenesis of Drosophila. Nevertheless, the physiology of ACER has yet to be comprehensively understood. Herein, we employed RNA interference to down-regulate the expression of ACER in Drosophila's heart and swept source optical coherence tomography to assess whether ACER is required for cardiac functions in living adult flies. Several contractile parameters of Drosophila heart, including the heart rate (HR), end-diastolic diameter (EDD), end-systolic diameter (ESD), percent fractional shortening (%FS), and stress-induced cardiac performance, are shown, which are age dependent. These age-dependent cardiac functions declined significantly when ACER was down-regulated. Moreover, the lifespans of ACER knock-down flies were significantly shorter than those of wild-type control flies. Thus, we posit that ACER, the Drosophila ortholog of mammalian angiotensin-converting enzyme 2 (ACE2), is essential for both heart physiology and longevity of animals. Since mammalian ACE2 controls many cardiovascular physiological features and is implicated in cardiomyopathies, our findings that ACER plays conserved roles in genetically tractable animals will pave the way for uncovering the genetic pathway that controls the renin-angiotensin system.

E-cadherin can replace N-cadherin during secretory-stage enamel development.

PubMed

Guan, Xiaomu; Bidlack, Felicitas B; Stokes, Nicole; Bartlett, John D

2014-01-01

N-cadherin is a cell-cell adhesion molecule and deletion of N-cadherin in mice is embryonic lethal. During the secretory stage of enamel development, E-cadherin is down-regulated and N-cadherin is specifically up-regulated in ameloblasts when groups of ameloblasts slide by one another to form the rodent decussating enamel rod pattern. Since N-cadherin promotes cell migration, we asked if N-cadherin is essential for ameloblast cell movement during enamel development. The enamel organ, including its ameloblasts, is an epithelial tissue and for this study a mouse strain with N-cadherin ablated from epithelium was generated. Enamel from wild-type (WT) and N-cadherin conditional knockout (cKO) mice was analyzed. μCT and scanning electron microscopy showed that thickness, surface structure, and prism pattern of the cKO enamel looked identical to WT. No significant difference in hardness was observed between WT and cKO enamel. Interestingly, immunohistochemistry revealed the WT and N-cadherin cKO secretory stage ameloblasts expressed approximately equal amounts of total cadherins. Strikingly, E-cadherin was not normally down-regulated during the secretory stage in the cKO mice suggesting that E-cadherin can compensate for the loss of N-cadherin. Previously it was demonstrated that bone morphogenetic protein-2 (BMP2) induces E- and N-cadherin expression in human calvaria osteoblasts and we show that the N-cadherin cKO enamel organ expressed significantly more BMP2 and significantly less of the BMP antagonist Noggin than did WT enamel organ. The E- to N-cadherin switch at the secretory stage is not essential for enamel development or for forming the decussating enamel rod pattern. E-cadherin can substitute for N-cadherin during these developmental processes. Bmp2 expression may compensate for the loss of N-cadherin by inducing or maintaining E-cadherin expression when E-cadherin is normally down-regulated. Notably, this is the first demonstration of a natural endogenous increase in E-cadherin expression due to N-cadherin ablation in a healthy developing tissue.

CCCTC-binding Factor Mediates Effects of Glucose On Beta Cell Survival

PubMed Central

Tsui, Shanli; Dai, Wei; Lu, Luo

2013-01-01

Objectives Pancreatic islet β-cell survival is important in regulating insulin activities and maintaining glucose homeostasis. Recently, Pax6 has been shown to be essential for many vital functions in β-cells, though the molecular mechanisms of its regulation in β-cells remain unclear. The present study investigates the novel effects of glucose- and insulin-induced CTCF activity on Pax6 gene expression as well as the subsequent effects of insulin-activated signaling pathways on β-cell proliferation. Material and methods Pancreatic β-TC-1-6 cells were cultured in DMEM medium and stimulated with high concentrations of glucose (5 to 125 mM) and cell viability was assessed by MTT assays. The effect of CTCF on Pax6 was evaluated in high glucose-induced and CCCTC-binding Factor (CTCF)/Erk suppressed cells by promoter reporter and Western analyses. Results Increases in glucose and insulin concentrations up-regulated CTCF and consequently down-regulated Pax6 in β-cell survival and proliferation. Knocking-down CTCF directly affected Pax6 transcription through CTCF binding and blocked the response to glucose. Altered Erk activity mediated the effects of CTCF on controlling Pax6 expression, which partially regulates β-cell proliferation. Conclusions CTCF functions as a molecular mediator between insulin-induced upstream Erk signaling and Pax6 expression in pancreatic β-cells. This pathway may contribute to regulation of β-cell survival and proliferation. PMID:24354619

What is really in control of skin immunity: lymphocytes, dendritic cells, or keratinocytes? facts and controversies.

PubMed

Rupec, Rudolf A; Boneberger, Susanne; Ruzicka, Thomas

2010-01-01

The pathophysiology of atopic dermatitis is still under discussion. Although it is widely accepted that environmental factors and a genetic predisposition are essential, the role of the innate and adaptive immune system and the functional cascade of the cells involved is still unclear. A concept that integrates all immune cells as equally essential has allure. In addition, barrier abnormalities due to mutations of the gene coding for filaggrin and down-regulation of antimicrobial peptides, such as LL-37 and beta-defensins 2 and 3, were very recently found to be relevant for the pathogenesis of atopic dermatitis. Copyright 2010 Elsevier Inc. All rights reserved.

Distinct functions of Crumbs regulating slit diaphragms and endocytosis in Drosophila nephrocytes.

PubMed

Hochapfel, Florian; Denk, Lucia; Mendl, Gudrun; Schulze, Ulf; Maaßen, Christine; Zaytseva, Yulia; Pavenstädt, Hermann; Weide, Thomas; Rachel, Reinhard; Witzgall, Ralph; Krahn, Michael P

2017-12-01

Mammalian podocytes, the key determinants of the kidney's filtration barrier, differentiate from columnar epithelial cells and several key determinants of apical-basal polarity in the conventional epithelia have been shown to regulate podocyte morphogenesis and function. However, little is known about the role of Crumbs, a conserved polarity regulator in many epithelia, for slit-diaphragm formation and podocyte function. In this study, we used Drosophila nephrocytes as model system for mammalian podocytes and identified a conserved function of Crumbs proteins for cellular morphogenesis, nephrocyte diaphragm assembly/maintenance, and endocytosis. Nephrocyte-specific knock-down of Crumbs results in disturbed nephrocyte diaphragm assembly/maintenance and decreased endocytosis, which can be rescued by Drosophila Crumbs as well as human Crumbs2 and Crumbs3, which were both expressed in human podocytes. In contrast to the extracellular domain, which facilitates nephrocyte diaphragm assembly/maintenance, the intracellular FERM-interaction motif of Crumbs is essential for regulating endocytosis. Moreover, Moesin, which binds to the FERM-binding domain of Crumbs, is essential for efficient endocytosis. Thus, we describe here a new mechanism of nephrocyte development and function, which is likely to be conserved in mammalian podocytes.

Formation of the sacrum requires down-regulation of sonic hedgehog signaling in the sacral intervertebral discs.

PubMed

Bonavita, Raffaella; Vincent, Kathleen; Pinelli, Robert; Dahia, Chitra Lekha

2018-05-21

In humans, the sacrum forms an important component of the pelvic arch, and it transfers the weight of the body to the lower limbs. The sacrum is formed by collapse of the intervertebral discs (IVDs) between the five sacral vertebrae during childhood, and their fusion to form a single bone. We show that collapse of the sacral discs in the mouse is associated with the down-regulation of sonic hedgehog (SHH) signaling in the nucleus pulposus (NP) of the disc, and many aspects of this phenotype can be reversed by experimental postnatal activation of HH signaling. We have previously shown that SHH signaling is essential for the normal postnatal growth and differentiation of intervertebral discs elsewhere in the spine, and that loss of SHH signaling leads to pathological disc degeneration, a very common disorder of aging. Thus, loss of SHH is pathological in one region of the spine but part of normal development in another. © 2018. Published by The Company of Biologists Ltd.

RNAi assisted genome evolution unveils yeast mutants with improved xylose utilization.

PubMed

HamediRad, Mohammad; Lian, Jiazhang; Li, Hejun; Zhao, Huimin

2018-06-01

Xylose is a major component of lignocellulosic biomass, one of the most abundant feedstocks for biofuel production. Therefore, efficient and rapid conversion of xylose to ethanol is crucial in the viability of lignocellulosic biofuel plants. In this study, RNAi Assisted Genome Evolution (RAGE) was used to improve the xylose utilization rate in SR8, one of the most efficient publicly available xylose utilizing Saccharomyces cerevisiae strains. To identify gene targets for further improvement, we created a genome-scale library consisting of both genetic over-expression and down-regulation mutations in SR8. Followed by screening in media containing xylose as the sole carbon source, yeast mutants with 29% faster xylose utilization, and 45% higher ethanol productivity were obtained relative to the parent strain. Two known and two new effector genes were identified in these mutant strains. Notably, down-regulation of CDC11, an essential gene, resulted in faster xylose utilization, and this gene target cannot be identified in genetic knock-out screens. © 2018 Wiley Periodicals, Inc.

Neural correlates of reappraisal considering working memory capacity and cognitive flexibility.

PubMed

Zaehringer, Jenny; Falquez, Rosalux; Schubert, Anna-Lena; Nees, Frauke; Barnow, Sven

2018-01-09

Cognitive reappraisal of emotion is strongly related to long-term mental health. Therefore, the exploration of underlying cognitive and neural mechanisms has become an essential focus of research. Considering that reappraisal and executive functions rely on a similar brain network, the question arises whether behavioral differences in executive functions modulate neural activity during reappraisal. Using functional neuroimaging, the present study aimed to analyze the role of working memory capacity (WMC) and cognitive flexibility in brain activity during down-regulation of negative emotions by reappraisal in N = 20 healthy participants. Results suggests that WMC and cognitive flexibility were negatively correlated with prefrontal activity during reappraisal condition. Here, results also revealed a negative correlation between cognitive flexibility and amygdala activation. These findings provide first hints that (1) individuals with lower WMC and lower cognitive flexibility might need more higher-order cognitive neural resources in order to down-regulate negative emotions and (2) cognitive flexibility relates to emotional reactivity during reappraisal.

Protein Kinase C- ɛ Regulates the Apoptosis and Survival of Glioma Cells

PubMed Central

Okhrimenko, Hana; Lu, Wei; Xiang, Cunli; Hamburger, Nathan; Kazimirsky, Gila; Brodie, Chaya

2005-01-01

In this study, we examined the role of protein kinase C (PKC)-ɛ in the apoptosis and survival of glioma cells using tumor necrosis factor–related apoptosis inducing ligand (TRAIL)- stimulated cells and silencing of PKCɛ expression. Treatment of glioma cells with TRAIL induced activation, caspase-dependent cleavage, and down-regulation of PKCɛ within 3 to 5 hours of treatment. Overexpression of PKCɛ inhibited the apoptosis induced by TRAIL, acting downstream of caspase 8 and upstream of Bid cleavage and cytochrome c release from the mitochondria. A caspase-resistant PKCɛ mutant (D383A) was more protective than PKCɛ, suggesting that both the cleavage of PKCɛ and its down-regulation contributed to the apoptotic effect of TRAIL. To further study the role of PKCɛ in glioma cell apoptosis, we employed short interfering RNAs directed against the mRNA of PKCɛ and found that silencing of PKCɛ expression induced apoptosis of various glioma cell lines and primary glioma cultures. To delineate the molecular mechanisms involved in the apoptosis induced by silencing of PKCɛ, we examined the expression and phosphorylation of various apoptosis-related proteins. We found that knockdown of PKCɛ did not affect the expression of Bcl2 and Bax or the phosphorylation and expression of Erk1/2, c-Jun-NH2-kinase, p38, or STAT, whereas it selectively reduced the expression of AKT. Similarly, TRAIL reduced the expression of AKT in glioma cells and this decrease was abolished in cells overexpressing PKCɛ. Our results suggest that the cleavage of PKCɛ and its down-regulation play important roles in the apoptotic effect of TRAIL. Moreover, PKCɛ regulates AKT expression and is essential for the survival of glioma cells. PMID:16103081

Thyroid Hormones and Growth in Health and Disease

PubMed Central

Tarım, Ömer

2011-01-01

Thyroid hormones regulate growth by several mechanisms. In addition to their negative feedback effect on the stimulatory hormones thyrotropin-releasing hormone (TRH) and thyrotropin (TSH), thyroid hormones also regulate their receptors in various physiological and pathological conditions. Up-regulation and down-regulation of the thyroid receptors fine-tune the biological effects exerted by the thyroid hormones. Interestingly, the deiodinase enzyme system is another intrinsic regulator of thyroid physiology that adjusts the availability of thyroid hormones to the tissues, which is essential for normal growth and development. Almost all chronic diseases of childhood impair growth and development. Every disease may have a unique mechanism to halt linear growth, but reduced serum concentration or diminished local availability of thyroid hormones seems to be a common pathway. Therefore, the effects of systemic diseases on thyroid physiology must be taken into consideration in the evaluation of growth retardation in affected children. Conflict of interest:None declared. PMID:21750631

Reversible epigenetic down-regulation of MHC molecules by devil facial tumour disease illustrates immune escape by a contagious cancer

PubMed Central

Siddle, Hannah V.; Kreiss, Alexandre; Tovar, Cesar; Yuen, Chun Kit; Cheng, Yuanyuan; Belov, Katherine; Swift, Kate; Pearse, Anne-Maree; Hamede, Rodrigo; Jones, Menna E.; Skjødt, Karsten; Woods, Gregory M.; Kaufman, Jim

2013-01-01

Contagious cancers that pass between individuals as an infectious cell line are highly unusual pathogens. Devil facial tumor disease (DFTD) is one such contagious cancer that emerged 16 y ago and is driving the Tasmanian devil to extinction. As both a pathogen and an allograft, DFTD cells should be rejected by the host–immune response, yet DFTD causes 100% mortality among infected devils with no apparent rejection of tumor cells. Why DFTD cells are not rejected has been a question of considerable confusion. Here, we show that DFTD cells do not express cell surface MHC molecules in vitro or in vivo, due to down-regulation of genes essential to the antigen-processing pathway, such as β2-microglobulin and transporters associated with antigen processing. Loss of gene expression is not due to structural mutations, but to regulatory changes including epigenetic deacetylation of histones. Consequently, MHC class I molecules can be restored to the surface of DFTD cells in vitro by using recombinant devil IFN-γ, which is associated with up-regulation of the MHC class II transactivator, a key transcription factor with deacetylase activity. Further, expression of MHC class I molecules by DFTD cells can occur in vivo during lymphocyte infiltration. These results explain why T cells do not target DFTD cells. We propose that MHC-positive or epigenetically modified DFTD cells may provide a vaccine to DFTD. In addition, we suggest that down-regulation of MHC molecules using regulatory mechanisms allows evolvability of transmissible cancers and could affect the evolutionary trajectory of DFTD. PMID:23479617

Sirt2 suppresses glioma cell growth through targeting NF-κB–miR-21 axis

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

Li, Ya’nan; Dai, Dongwei; Lu, Qiong

Highlights: •Sirt2 expression is down-regulated in human glioma tissues and cell lines. •Sirt2 regresses glioma cell growth and colony formation via inducing apoptosis. •miR-21 is essential for the functions of Sirt2 in glioma cells. •Sirt2 deacetylates p65 to decrease miR-21 expression. -- Abstract: Sirtuins are NAD{sup +}-dependent deacetylases that regulate numerous cellular processes including aging, DNA repair, cell cycle, metabolism, and survival under stress conditions. The roles of sirtuin family members are widely studied in carcinogenesis. However, their roles in glioma remain unclear. Here we report that Sir2 was under expressed in human glioma tissues and cell lines. We foundmore » that Sirt2 overexpression decreased cell proliferation and colony formation capacity. In addition, Sirt2 overexpression induced cellular apoptosis via up-regulating cleaved caspase 3 and Bax, and down-regulating anti-apoptotic protein Bcl-2. Sirt2 knockdown obtained opposing results. We showed that Sirt2 overexpression inhibited miR-21 expression, and Sirt2 was not sufficient to reduce cell proliferation and colony formation as well as to induce apoptosis when miR-21 was knocked down in glioma cells. Mechanically, we demonstrated that Sirt2 deacetylated p65 at K310 and blocked p65 binding to the promoter region of miR-21, thus regressing the transcription of miR-21. In summary, Sirt2 is critical in human glioma via NF-κB–miR-21 pathway and Sirt2 activator may serve as candidate drug for glioma therapy.« less

Inhibition of melanogenesis by β-caryophyllene from lime mint essential oil in mouse B16 melanoma cells.

PubMed

Yang, C-H; Huang, Y-C; Tsai, M-L; Cheng, C-Y; Liu, L-L; Yen, Y-W; Chen, W-L

2015-10-01

Volatile essential oils of mint species are used for cosmetics and in skin care products. In this study, we evaluated the main chemical components of the lime mint and the anti-melanogenic properties of its main components. The essential oil was analysed by gas chromatography-mass spectrometry (GC/MS). The anti-melanogenic effects of mint essential oil and β-caryophyllene were investigated in B16F10 murine melanoma cells. The main components of lime mint essential oil were found to be D-limonene (41.10%), D-carvone (8.58%), δ-selinene (6.73%) and β-caryophyllene (6.24%). The lime mint essential oil reduced melanin production in a dose-dependent manner in murine B16F10 cells. β-Caryophyllene, one of the main compounds in lime mint essential oil, could reduce melanogenesis by down-regulating the expression of MITF, TRP-1, TRP-2 and tyrosinase, resulting in a decrease in melanin content decrease. These results reveal that lime mint essential oil and β-caryophyllene are considered to be valuable as potential skin-whitening agents. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Proteomic analysis indicates that mitochondrial energy metabolism in skeletal muscle tissue is negatively correlated with feed efficiency in pigs

NASA Astrophysics Data System (ADS)

Fu, Liangliang; Xu, Yueyuan; Hou, Ye; Qi, Xiaolong; Zhou, Lian; Liu, Huiying; Luan, Yu; Jing, Lu; Miao, Yuanxin; Zhao, Shuhong; Liu, Huazhen; Li, Xinyun

2017-03-01

Feed efficiency (FE) is a highly important economic trait in pig production. Investigating the molecular mechanisms of FE is essential for trait improvement. In this study, the skeletal muscle proteome of high-FE and low-FE pigs were investigated by the iTRAQ approach. A total of 1780 proteins were identified, among which 124 proteins were differentially expressed between the high- and low-FE pigs, with 74 up-regulated and 50 down-regulated in the high-FE pigs. Ten randomly selected differentially expressed proteins (DEPs) were validated by Western blotting and quantitative PCR (qPCR). Gene ontology (GO) analysis showed that all the 25 DEPs located in mitochondria were down-regulated in the high-FE pigs. Furthermore, the glucose-pyruvate-tricarboxylic acid (TCA)-oxidative phosphorylation energy metabolism signaling pathway was found to differ between high- and low-FE pigs. The key enzymes involved in the conversion of glucose to pyruvate were up-regulated in the high-FE pigs. Thus, our results suggested mitochondrial energy metabolism in the skeletal muscle tissue was negatively correlated with FE in pigs, and glucose utilization to generate ATP was more efficient in the skeletal muscle tissue of high-FE pigs. This study offered new targets and pathways for improvement of FE in pigs.

Proteomic analysis indicates that mitochondrial energy metabolism in skeletal muscle tissue is negatively correlated with feed efficiency in pigs

PubMed Central

Fu, Liangliang; Xu, Yueyuan; Hou, Ye; Qi, Xiaolong; Zhou, Lian; Liu, Huiying; Luan, Yu; Jing, Lu; Miao, Yuanxin; Zhao, Shuhong; Liu, Huazhen; Li, Xinyun

2017-01-01

Feed efficiency (FE) is a highly important economic trait in pig production. Investigating the molecular mechanisms of FE is essential for trait improvement. In this study, the skeletal muscle proteome of high-FE and low-FE pigs were investigated by the iTRAQ approach. A total of 1780 proteins were identified, among which 124 proteins were differentially expressed between the high- and low-FE pigs, with 74 up-regulated and 50 down-regulated in the high-FE pigs. Ten randomly selected differentially expressed proteins (DEPs) were validated by Western blotting and quantitative PCR (qPCR). Gene ontology (GO) analysis showed that all the 25 DEPs located in mitochondria were down-regulated in the high-FE pigs. Furthermore, the glucose-pyruvate-tricarboxylic acid (TCA)-oxidative phosphorylation energy metabolism signaling pathway was found to differ between high- and low-FE pigs. The key enzymes involved in the conversion of glucose to pyruvate were up-regulated in the high-FE pigs. Thus, our results suggested mitochondrial energy metabolism in the skeletal muscle tissue was negatively correlated with FE in pigs, and glucose utilization to generate ATP was more efficient in the skeletal muscle tissue of high-FE pigs. This study offered new targets and pathways for improvement of FE in pigs. PMID:28345649

Contributions of mRNA abundance, ribosome loading, and post- or peri-translational effects to temporal repression of C. elegans heterochronic miRNA targets

PubMed Central

Stadler, Michael; Artiles, Karen; Pak, Julia; Fire, Andrew

2012-01-01

miRNAs are post-transcriptional regulators of gene activity that reduce protein accumulation from target mRNAs. Elucidating precise molecular effects that animal miRNAs have on target transcripts has proven complex, with varied evidence indicating that miRNA regulation may produce different molecular outcomes in different species, systems, and/or physiological conditions. Here we use high-throughput ribosome profiling to analyze detailed translational parameters for five well-studied targets of miRNAs that regulate C. elegans developmental timing. For two targets of the miRNA lin-4 (lin-14 and lin-28), functional down-regulation was associated with decreases in both overall mRNA abundance and ribosome loading; however, these changes were of substantially smaller magnitude than corresponding changes observed in protein abundance. For three functional targets of the let-7 miRNA family for which down-regulation is critical in temporal progression of the animal (daf-12, hbl-1, and lin-41), we observed only modest changes in mRNA abundance and ribosome loading. lin-41 provides a striking example in that populations of ribosome-protected fragments from this gene remained essentially unchanged during the L3–L4 time interval when lin-41 activity is substantially down-regulated by let-7. Spectra of ribosomal positions were also examined for the five lin-4 and let-7 target mRNAs as a function of developmental time, with no indication of miRNA-induced ribosomal drop-off or significant pauses in translation. These data are consistent with models in which physiological regulation by this set of C. elegans miRNAs derives from combinatorial effects including suppressed recruitment/activation of translational machinery, compromised stability of target messages, and post- or peri-translational effects on lifetimes of polypeptide products. PMID:22855835

Essential oil of Artemisia argyi suppresses inflammatory responses by inhibiting JAK/STATs activation.

PubMed

Chen, Lin-Lin; Zhang, Hao-Jun; Chao, Jung; Liu, Jun-Feng

2017-05-23

Artemisia argyi is a herbal medicine traditionally used in Asia for the treatment of bronchitis, dermatitis and arthritis. Recent studies revealed the anti-inflammatory effect of essential oil in this plant. However, the mechanisms underlying the therapeutic potential have not been well elucidated. The present study is aimed to verify its anti-inflammatory effect and investigate the probable mechanisms. The essential oil from Artemisia argyi (AAEO) was initially tested against LPS-induced production of inflammatory mediators and cytokines in RAW264.7 macrophages. Protein and mRNA expressions of iNOS and COX-2 were determined by Western blotting and RT-PCR analysis, respectively. The effects on the activation of MAPK/NF-κB/AP-1 and JAK/STATs pathway were also investigated by western blot. Meanwhile, in vivo anti-inflammatory effect was examined by histologic and immunohistochemical analysis in TPA-induced mouse ear edema model. The results of in vitro experiments showed that AAEO dose-dependently suppressed the release of pro-inflammatory mediators (NO, PGE 2 and ROS) and cytokines (TNF-α, IL-6, IFN-β and MCP-1) in LPS-induced RAW264.7 macrophages. It down-regulated iNOS and COX-2 protein and mRNA expression but did not affect the activity of these two enzymes. AAEO significantly inhibited the phosphorylation of JAK2 and STAT1/3, but not the activation of MAPK and NF-κB cascades. In animal model, oral administration of AAEO significantly attenuated TPA-induced mouse ear edema and decreased the protein level of COX-2. AAEO suppresses inflammatory responses via down-regulation of the JAK/STATs signaling and ROS scavenging, which could contribute, at least in part, to the anti-inflammatory effect of AAEO. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Health Risk Assessment of Women in Submarines: Reproductive and Developmental Toxicity Evaluation of Major Submarine Atmosphere Components (CO, CO2 and O2) in Rats (Rattus norvegicus) - Phase II (Neurological and Reproductive Performance Study)

DTIC Science & Technology

2011-10-11

exposed parents. Statistically significant increases in hematopoietic activity (mild polycythemia , leukocytosis and thrombocytosis) were...Tables 25 & 26). Polycythemia (increased red blood cells, with expected increases in hemoglobin and hematocrit) is an established effect of

Ezrin is down-regulated in diabetic kidney glomeruli and regulates actin reorganization and glucose uptake via GLUT1 in cultured podocytes.

PubMed

Wasik, Anita A; Koskelainen, Susanna; Hyvönen, Mervi E; Musante, Luca; Lehtonen, Eero; Koskenniemi, Kerttu; Tienari, Jukka; Vaheri, Antti; Kerjaschki, Dontscho; Szalay, Csaba; Révész, Csaba; Varmanen, Pekka; Nyman, Tuula A; Hamar, Peter; Holthöfer, Harry; Lehtonen, Sanna

2014-06-01

Diabetic nephropathy is a complication of diabetes and a major cause of end-stage renal disease. To characterize the early pathophysiological mechanisms leading to glomerular podocyte injury in diabetic nephropathy, we performed quantitative proteomic profiling of glomeruli isolated from rats with streptozotocin-induced diabetes and controls. Fluorescence-based two-dimensional difference gel electrophoresis, coupled with mass spectrometry, identified 29 differentially expressed spots, including actin-binding protein ezrin and its interaction partner, NHERF2, which were down-regulated in the streptozotocin group. Knockdown of ezrin by siRNA in cultured podocytes increased glucose uptake compared with control siRNA-transfected cells, apparently by increasing translocation of glucose transporter GLUT1 to the plasma membrane. Knockdown of ezrin also induced actin remodeling under basal conditions, but reduced insulin-stimulated actin reorganization. Ezrin-dependent actin remodeling involved cofilin-1 that is essential for the turnover and reorganization of actin filaments. Phosphorylated, inactive cofilin-1 was up-regulated in diabetic glomeruli, suggesting altered actin dynamics. Furthermore, IHC analysis revealed reduced expression of ezrin in the podocytes of patients with diabetes. Our findings suggest that ezrin may play a role in the development of the renal complication in diabetes by regulating transport of glucose and organization of the actin cytoskeleton in podocytes. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Response to copper of Acidithiobacillus ferrooxidans ATCC 23270 grown in elemental sulfur.

PubMed

Almárcegui, Rodrigo J; Navarro, Claudio A; Paradela, Alberto; Albar, Juan Pablo; von Bernath, Diego; Jerez, Carlos A

2014-11-01

The response of Acidithiobacillus ferrooxidans ATCC 23270 to copper was analyzed in sulfur-grown cells by using quantitative proteomics. Forty-seven proteins showed altered levels in cells grown in the presence of 50 mM copper sulfate. Of these proteins, 24 were up-regulated and 23 down-regulated. As seen before in ferrous iron-grown cells, there was a notorious up-regulation of RND-type Cus systems and different RND-type efflux pumps, indicating that these proteins are very important in copper resistance. Copper also triggered the down-regulation of the major outer membrane porin of A. ferrooxidans in sulfur-grown bacteria, suggesting they respond to the metal by decreasing the influx of cations into the cell. On the contrary, copper in sulfur-grown cells caused an overexpression of putative TadA and TadB proteins known to be essential for biofilm formation in bacteria. Surprisingly, sulfur-grown microorganisms showed increased levels of proteins related with energy generation (rus and petII operons) in the presence of copper. Although rus operon is overexpressed mainly in cells grown in ferrous iron, the up-regulation of rusticyanin in sulfur indicates a possible role for this protein in copper resistance as well. Finally, copper response in A. ferrooxidans appears to be influenced by the substrate being oxidized by the microorganism. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Fibromodulin modulates myoblast differentiation by controlling calcium channel.

PubMed

Lee, Eun Ju; Nam, Joo Hyun; Choi, Inho

2018-06-16

Fibromodulin (FMOD) is a proteoglycan present in extracellular matrix (ECM). Based on our previous findings that FMOD controls myoblast differentiation by regulating the gene expressions of collagen type I alpha 1 (COL1α1) and integral membrane protein 2 A (Itm2a), we undertook this study to investigate relationships between FMOD and calcium channels and to understand further the mechanism by which they control myoblast differentiation. Gene expression studies and luciferase reporter assays showed FMOD affected calcium channel gene expressions by regulating calcium channel gene promoter, and patch-clamp experiments showed both L- and T-type calcium channel currents were almost undetectable in FMOD knocked down cells. In addition, gene knock-down studies demonstrated the COL1α1 and Itm2a genes both regulate the expressions of calcium channel genes. Studies using a cardiotoxin-induced mouse muscle injury model demonstrated calcium channels play important roles in the regeneration of muscle tissue, possibly by promoting the differentiation of muscle stem cells (MSCs). Summarizing, the study demonstrates ECM components secreted by myoblasts during differentiation provide an essential environment for muscle differentiation and regeneration. Copyright © 2018 Elsevier Inc. All rights reserved.

bFGF Regulates PI3-Kinase-Rac1-JNK Pathway and Promotes Fibroblast Migration in Wound Healing

PubMed Central

Kanazawa, Shigeyuki; Fujiwara, Toshihiro; Matsuzaki, Shinsuke; Shingaki, Kenta; Taniguchi, Manabu; Miyata, Shingo; Tohyama, Masaya; Sakai, Yasuo; Yano, Kenji; Hosokawa, Ko; Kubo, Tateki

2010-01-01

Fibroblast proliferation and migration play important roles in wound healing. bFGF is known to promote both fibroblast proliferation and migration during the process of wound healing. However, the signal transduction of bFGF-induced fibroblast migration is still unclear, because bFGF can affect both proliferation and migration. Herein, we investigated the effect of bFGF on fibroblast migration regardless of its effect on fibroblast proliferation. We noticed involvement of the small GTPases of the Rho family, PI3-kinase, and JNK. bFGF activated RhoA, Rac1, PI3-kinase, and JNK in cultured fibroblasts. Inhibition of RhoA did not block bFGF-induced fibroblast migration, whereas inhibition of Rac1, PI3-kinase, or JNK blocked the fibroblast migration significantly. PI3-kinase-inhibited cells down-regulated the activities of Rac1 and JNK, and Rac1-inhibited cells down-regulated JNK activity, suggesting that PI3-kinase is upstream of Rac1 and that JNK is downstream of Rac1. Thus, we concluded that PI3-kinase, Rac1, and JNK were essential for bFGF-induced fibroblast migration, which is a novel pathway of bFGF-induced cell migration. PMID:20808927

ω-3 PUFAs ameliorate liver fibrosis and inhibit hepatic stellate cells proliferation and activation by promoting YAP/TAZ degradation.

PubMed

Zhang, Kun; Chang, Yanan; Shi, Zhemin; Han, Xiaohui; Han, Yawei; Yao, Qingbin; Hu, Zhimei; Cui, Hongmei; Zheng, Lina; Han, Tao; Hong, Wei

2016-07-20

Elevated levels of the transcriptional regulators Yes-associated protein (YAP) and transcriptional coactivators with PDZ-binding motif (TAZ), key effectors of the Hippo pathway, have been shown to play essential roles in controlling liver cell fate and the activation of hepatic stellate cells (HSCs). The dietary intake of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) has been positively associated with a number of health benefits including prevention and reduction of cardiovascular diseases, inflammation and cancers. However, little is known about the impact of ω-3 PUFAs on liver fibrosis. In this study, we used CCl4-induced liver fibrosis mouse model and found that YAP/TAZ is over-expressed in the fibrotic liver and activated HSCs. Fish oil administration to the model mouse attenuates CCl4-induced liver fibrosis. Further study revealed that ω-3 PUFAs down-regulate the expression of pro-fibrogenic genes in activated HSCs and fibrotic liver, and the down-regulation is mediated via YAP, thus identifying YAP as a target of ω-3 PUFAs. Moreover, ω-3 PUFAs promote YAP/TAZ degradation in a proteasome-dependent manner. Our data have identified a mechanism of ω-3 PUFAs in ameliorating liver fibrosis.

c-Myc plays a key role in TADs-induced apoptosis and cell cycle arrest in human hepatocellular carcinoma cells

PubMed Central

Zhang, Dongdong; Qi, Junpeng; Liu, Rui; Dai, Bingling; Ma, Weina; Zhan, Yingzhuan; Zhang, Yanmin

2015-01-01

Cancer cell growth is complicated progression which is regulated and controlled by multiple factors including cell cycle, migration and apoptosis. In present study, we report that TADs, a novel derivative of taspine, has an essential role in resisting hepatocellular carcinoma growth (including arrest cell cycle) and migration, and inducing cell apoptosis. Our findings demonstrated that the TADs showed good inhibition on the hepatoma cell growth and migration, and good action on apoptosis induction. Using genome-wide microarray analysis, we found the down-regulated growth and apoptosis factors, and selected down-regulated genes were confirmed by Western blot. Knockdown of a checkpoint c-Myc by siRNA significantly attenuated tumor inhibition and apoptosis effects of TADs. Moreover, our results indicated TADs could simultaneously increase cyclin D1 protein levels and decrease amount of cyclin E, cyclin B1 and cdc2 of the cycle proteins, and also TADs reduced Bcl-2 expression, and upregulated Bad, Bak and Bax activities. In conclusion, these results illustrated that TADs is a key factor in growth and apoptosis signaling inhibitor, has potential in cancer therapy. PMID:26045987

Natural derivatives of curcumin attenuate the Wnt/{beta}-catenin pathway through down-regulation of the transcriptional coactivator p300

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

Ryu, Min-Jung; Cho, Munju; Song, Jie-Young

2008-12-26

Curcumin, a component of turmeric (Curcuma longa), has been reported to suppress {beta}-catenin response transcription (CRT), which is aberrantly activated in colorectal cancer. However, the effects of its natural analogs (demethoxycurcumin [DMC] and bisdemethoxycurcumin [BDMC]) and metabolite (tetrahydrocurcumin [THC]) on the Wnt/{beta}-catenin pathway have not been investigated. Here, we show that DMC and BDMC suppressed CRT that was activated by Wnt3a conditioned-medium (Wnt3a-CM) without altering the level of intracellular {beta}-catenin, and inhibited the growth of various colon cancer cells, with comparable potency to curcumin. Additionally, DMC and BDMC down-regulated p300, which is a positive regulator of the Wnt/{beta}-catenin pathway. Notably,more » THC also inhibited CRT and cell proliferation, but to a much lesser degree than curcumin, DMC, or BDMC, indicating that the conjugated bonds in the central seven-carbon chain of curcuminoids are essential for the inhibition of Wnt/{beta}-catenin pathway and the anti-proliferative activity of curcuminoids. Thus, our findings suggest that curcumin derivatives inhibit the Wnt/{beta}-catenin pathway by decreasing the amount of the transcriptional coactivator p300.« less

Unraveling the Rat Intestine, Spleen and Liver Genome-Wide Transcriptome after the Oral Administration of Lavender Oil by a Two-Color Dye-Swap DNA Microarray Approach

PubMed Central

Kubo, Hiroko; Shibato, Junko; Saito, Tomomi; Ogawa, Tetsuo; Rakwal, Randeep; Shioda, Seiji

2015-01-01

The use of lavender oil (LO) – a commonly, used oil in aromatherapy, with well-defined volatile components linalool and linalyl acetate – in non-traditional medicine is increasing globally. To understand and demonstrate the potential positive effects of LO on the body, we have established an animal model in this current study, investigating the orally administered LO effects genome wide in the rat small intestine, spleen, and liver. The rats were administered LO at 5 mg/kg (usual therapeutic dose in humans) followed by the screening of differentially expressed genes in the tissues, using a 4×44-K whole-genome rat chip (Agilent microarray platform; Agilent Technologies, Palo Alto, CA, USA) in conjunction with a dye-swap approach, a novelty of this study. Fourteen days after LO treatment and compared with a control group (sham), a total of 156 and 154 up (≧ 1.5-fold)- and down (≦ 0.75-fold)-regulated genes, 174 and 66 up- (≧ 1.5-fold)- and down (≦ 0.75-fold)-regulated genes, and 222 and 322 up- (≧ 1.5-fold)- and down (≦ 0.75-fold)-regulated genes showed differential expression at the mRNA level in the small intestine, spleen and liver, respectively. The reverse transcription-polymerase chain reaction (RT-PCR) validation of highly up- and down-regulated genes confirmed the regulation of the Papd4, Lrp1b, Alb, Cyr61, Cyp2c, and Cxcl1 genes by LO as examples in these tissues. Using bioinformatics, including Ingenuity Pathway Analysis (IPA), differentially expressed genes were functionally categorized by their Gene Ontology (GO) and biological function and network analysis, revealing their diverse functions and potential roles in LO-mediated effects in rat. Further IPA analysis in particular unraveled the presence of novel genes, such as Papd4, Or8k5, Gprc5b, Taar5, Trpc6, Pld2 and Onecut3 (up-regulated top molecules) and Tnf, Slc45a4, Slc25a23 and Samt4 (down-regulated top molecules), to be influenced by LO treatment in the small intestine, spleen and liver, respectively. These results are the first such inventory of genes that are affected by lavender essential oil (LO) in an animal model, forming the basis for further in-depth bioinformatics and functional analyses and investigation. PMID:26161641

Down-regulation of placental mTOR, insulin/IGF-I signaling, and nutrient transporters in response to maternal nutrient restriction in the baboon.

PubMed

Kavitha, Jovita V; Rosario, Fredrick J; Nijland, Mark J; McDonald, Thomas J; Wu, Guoyao; Kanai, Yoshikatsu; Powell, Theresa L; Nathanielsz, Peter W; Jansson, Thomas

2014-03-01

The mechanisms by which maternal nutrient restriction (MNR) causes reduced fetal growth are poorly understood. We hypothesized that MNR inhibits placental mechanistic target of rapamycin (mTOR) and insulin/IGF-I signaling, down-regulates placental nutrient transporters, and decreases fetal amino acid levels. Pregnant baboons were fed control (ad libitum, n=11) or an MNR diet (70% of controls, n=11) from gestational day (GD) 30. Placenta and umbilical blood were collected at GD 165. Western blot was used to determine the phosphorylation of proteins in the mTOR, insulin/IGF-I, ERK1/2, and GSK-3 signaling pathways in placental homogenates and expression of glucose transporter 1 (GLUT-1), taurine transporter (TAUT), sodium-dependent neutral amino acid transporter (SNAT), and large neutral amino acid transporter (LAT) isoforms in syncytiotrophoblast microvillous membranes (MVMs). MNR reduced fetal weights by 13%, lowered fetal plasma concentrations of essential amino acids, and decreased the phosphorylation of placental S6K, S6 ribosomal protein, 4E-BP1, IRS-1, Akt, ERK-1/2, and GSK-3. MVM protein expression of GLUT-1, TAUT, SNAT-2 and LAT-1/2 was reduced in MNR. This is the first study in primates exploring placental responses to maternal undernutrition. Inhibition of placental mTOR and insulin/IGF-I signaling resulting in down-regulation of placental nutrient transporters may link maternal undernutrition to restricted fetal growth.

Systematic mutational analysis of the intracellular regions of yeast Gap1 permease.

PubMed

Merhi, Ahmad; Gérard, Nicolas; Lauwers, Elsa; Prévost, Martine; André, Bruno

2011-04-19

The yeast general amino acid permease Gap1 is a convenient model for studying the intracellular trafficking of membrane proteins. Present at the plasma membrane when the nitrogen source is poor, it undergoes ubiquitin-dependent endocytosis and degradation upon addition of a good nitrogen source, e.g., ammonium. It comprises 12 transmembrane domains (TM) flanked by cytosol-facing N- and C-terminal tails (NT, CT). The NT of Gap1 contains the acceptor lysines for ubiquitylation and its CT includes a sequence essential to exit from the endoplasmic reticulum (ER). We used alanine-scanning mutagenesis to isolate 64 mutant Gap1 proteins altered in the NT, the CT, or one of the five TM-connecting intracellular loops (L2, -4, -6, -8 and -10). We found 17 mutations (in L2, L8, L10 and CT) impairing Gap1 exit from the ER. Of the 47 mutant proteins reaching the plasma membrane normally, two are unstable and rapidly down-regulated even when the nitrogen source is poor. Six others are totally inactive and another four, altered in a 16-amino-acid sequence in the NT, are resistant to ammonium-induced down-regulation. Finally, a mutation in L6 causes missorting of Gap1 from the secretory pathway to the vacuole. Interestingly, this direct vacuolar sorting seems to be independent of Gap1 ubiquitylation. This study illustrates the importance of multiple intracellular regions of Gap1 in its secretion, transport activity, and down-regulation.

Genetic evidence that Nkx2.2 acts primarily downstream of Neurog3 in pancreatic endocrine lineage development

PubMed Central

Churchill, Angela J; Gutiérrez, Giselle Dominguez; Singer, Ruth A; Lorberbaum, David S; Fischer, Kevin A; Sussel, Lori

2017-01-01

Many pancreatic transcription factors that are essential for islet cell differentiation have been well characterized; however, because they are often expressed in several different cell populations, their functional hierarchy remains unclear. To parse out the spatiotemporal regulation of islet cell differentiation, we used a Neurog3-Cre allele to ablate Nkx2.2, one of the earliest and most broadly expressed islet transcription factors, specifically in the Neurog3+ endocrine progenitor lineage (Nkx2.2△endo). Remarkably, many essential components of the β cell transcriptional network that were down-regulated in the Nkx2.2KO mice, were maintained in the Nkx2.2△endo mice - yet the Nkx2.2△endo mice displayed defective β cell differentiation and recapitulated the Nkx2.2KO phenotype. This suggests that Nkx2.2 is not only required in the early pancreatic progenitors, but has additional essential activities within the endocrine progenitor population. Consistently, we demonstrate Nkx2.2 functions as an integral component of a modular regulatory program to correctly specify pancreatic islet cell fates. DOI: http://dx.doi.org/10.7554/eLife.20010.001 PMID:28071588

Investigation of the Anti-Melanogenic and Antioxidant Characteristics of Eucalyptus camaldulensis Flower Essential Oil and Determination of Its Chemical Composition.

PubMed

Huang, Huey-Chun; Ho, Ya-Chi; Lim, Jia-Min; Chang, Tzu-Yun; Ho, Chen-Lung; Chang, Tsong-Min

2015-05-07

The effects of essential oil from Eucalyptus camaldulensis flowers oil on melanogenesis and the oil's antioxidant characteristics were investigated. Assays of mushroom and cellular tyrosinase activities and melanin content of mouse melanoma cells were performed spectrophotometrically, and the expression of melanogenesis-related proteins was determined by Western blotting. The possible signaling pathways involved in essential oil-mediated depigmentation were also investigated using specific protein kinase inhibitors. The results revealed that E. camaldulensis flower essential oil effectively suppresses intracellular tyrosinase activity and decreases melanin amount in B16F10 mouse melanoma cells. The essential oil also exhibits antioxidant properties and effectively decreases intracellular reactive oxygen species (ROS) levels. The volatile chemical composition of the essential oil was analyzed with gas chromatography-mass spectrometry (GC/MS). The chemical constituents in the essential oil are predominately oxygenated monoterpenes (34.9%), followed by oxygenated sesquiterpenes (31.8%), monoterpene hydrocarbons (29.0%) and sesquiterpene hydrocarbons (4.3%). Our results indicated that E. camaldulensis flower essential oil inhibits melanogenesis through its antioxidant properties and by down-regulating both mitogen-activated protein kinases (MAPK) and protein kinase A (PKA) signaling pathways. The present study indicates that the essential oil has the potential to be developed into a skin care product.

Investigation of the Anti-Melanogenic and Antioxidant Characteristics of Eucalyptus camaldulensis Flower Essential Oil and Determination of Its Chemical Composition

PubMed Central

Huang, Huey-Chun; Ho, Ya-Chi; Lim, Jia-Min; Chang, Tzu-Yun; Ho, Chen-Lung; Chang, Tsong-Min

2015-01-01

The effects of essential oil from Eucalyptus camaldulensis flowers oil on melanogenesis and the oil’s antioxidant characteristics were investigated. Assays of mushroom and cellular tyrosinase activities and melanin content of mouse melanoma cells were performed spectrophotometrically, and the expression of melanogenesis-related proteins was determined by Western blotting. The possible signaling pathways involved in essential oil-mediated depigmentation were also investigated using specific protein kinase inhibitors. The results revealed that E. camaldulensis flower essential oil effectively suppresses intracellular tyrosinase activity and decreases melanin amount in B16F10 mouse melanoma cells. The essential oil also exhibits antioxidant properties and effectively decreases intracellular reactive oxygen species (ROS) levels. The volatile chemical composition of the essential oil was analyzed with gas chromatography–mass spectrometry (GC/MS). The chemical constituents in the essential oil are predominately oxygenated monoterpenes (34.9%), followed by oxygenated sesquiterpenes (31.8%), monoterpene hydrocarbons (29.0%) and sesquiterpene hydrocarbons (4.3%). Our results indicated that E. camaldulensis flower essential oil inhibits melanogenesis through its antioxidant properties and by down-regulating both mitogen-activated protein kinases (MAPK) and protein kinase A (PKA) signaling pathways. The present study indicates that the essential oil has the potential to be developed into a skin care product. PMID:25961954

Linker Histone Phosphorylation Regulates Global Timing of Replication Origin Firing*S⃞

PubMed Central

Thiriet, Christophe; Hayes, Jeffrey J.

2009-01-01

Despite the presence of linker histone in all eukaryotes, the primary function(s) of this histone have been difficult to clarify. Knock-out experiments indicate that H1s play a role in regulation of only a small subset of genes but are an essential component in mouse development. Here, we show that linker histone (H1) is involved in the global regulation of DNA replication in Physarum polycephalum. We find that genomic DNA of H1 knock-down cells is more rapidly replicated, an effect due at least in part to disruption of the native timing of replication fork firing. Immunoprecipitation experiments demonstrate that H1 is transiently lost from replicating chromatin via a process facilitated by phosphorylation. Our results suggest that linker histones generate a chromatin environment refractory to replication and that their transient removal via protein phosphorylation during S phase is a critical step in the epigenetic regulation of replication timing. PMID:19015270

Prognostic factors in patients with advanced renal cell carcinoma.

PubMed

Muriel López, Carolina; Esteban, Emilio; Berros, Jose Pablo; Pardo, Pablo; Astudillo, Aurora; Izquierdo, Marta; Crespo, Guillermo; Sanmamed, Miguel; Fonseca, Paula J; Martínez-Camblor, Pablo

2012-12-01

The purpose of this study was to evaluate prognostic factors in patients with RCC. The expression of several biomarkers were measured by immunohistochemistry (IHC), together with 2 analytic factors (thrombocytosis and neutrophilia), in 135 patients with advanced RCC treated with new targeted drugs (NTDs) (n = 67) and/or cytokines (CKs) (n = 68)-with 23 of the patients who received CKs also receiving NTDs-between July 1996 and February 2010. Relationships with overall survival (OS) and progression-free survival (PFS) were searched for. Univariate statistical analysis revealed that high expression of hypoxia-inducible factor-1α (HIF-1α) correlated with poor prognosis in NTD treatment (PFS, 5.4 vs. 13.5, low expression months; P = .033) and CK treatment (PFS, 3.3 vs. 5.7, low expression; P = .003). Overexpression of carbonic anhydrase IX (CAIX) was associated with better prognosis with NTD treatment (OS, 32.1 vs. 7.8 months; P < .001) and CK treatment (OS, 32.9 vs. 5.9 months; P = .001). Positive PTEN was related to good prognosis with sunitinib (PFS, 15.1 vs. 6.5 months; P = .003) and CKs (OS, 13.7 vs. 7.9 months; P = .039). Increased expression of p21 was related to poor prognosis with NTD treatment (PFS, 5.9 vs. 16.8 months; P = .024) and CK treatment (PFS, 3.9 vs. 7.5 months; P < .001) Thrombocytosis was related to poor prognosis with NTDs (OS, 15.9 vs. 26.7 months; P = .007) and CKs (OS, 5.9 vs. 14.3 months; P = .010). Neutrophilia was related to poor prognosis with NTDs (OS, 17.6 vs. 25.4 months; P = .063) and CKs (OS, 5.9 vs. 12.8 months; P = .035). Multivariate analysis revealed that overexpression of CAIX was a favorable prognostic factor independent of PFS (hazard ratio [HR], 0.107; P < .001) and OS (HR, 0.055; P < .001). HIF-1α, PTEN, p21, thrombocytosis, neutrophilia, and CAIX in particular are useful prognostic factors in patients with advanced RCC. Copyright © 2012 Elsevier Inc. All rights reserved.

Clinical utility of routine MPL exon 10 analysis in the diagnosis of essential thrombocythaemia and primary myelofibrosis.

PubMed

Boyd, Elaine M; Bench, Anthony J; Goday-Fernández, Andrea; Anand, Shubha; Vaghela, Krishna J; Beer, Phillip; Scott, Mike A; Bareford, David; Green, Anthony R; Huntly, Brian; Erber, Wendy N

2010-04-01

Approximately 50% of essential thrombocythaemia and primary myelo-fibrosis patients do not have a JAK2 V617F mutation. Up to 5% of these are reported to have a MPL exon 10 mutation but testing for MPL is not routine as there are multiple mutation types. The ability to routinely assess both JAK2 and MPL mutations would be beneficial in the differential diagnosis of unexplained thrombocytosis or myelofibrosis. We developed and applied a high resolution melt (HRM) assay, capable of detecting all known MPL mutations in a single analysis, for the detection of MPL exon 10 mutations. We assessed 175 ET and PMF patients, including 67 that were JAK2 V617F-negative by real time polymerase chain reaction (PCR). Overall, 19/175 (11%) patients had a MPL exon 10 mutation, of whom 16 were JAK2 V617F-negative (16/67; 24%). MPL mutation types were W515L (11), W515K (4), W515R (2) and W515A (1). One patient had both W515L and S505N MPL mutations and these were present in the same haemopoietic colonies. Real time PCR for JAK2 V617F analysis and HRM for MPL exon 10 status identified one or more clonal marker in 71% of patients. This combined genetic approach increases the sensitivity of meeting the World Health Organization diagnostic criteria for these myeloproliferative neoplasms.

Wilson disease: changes in methionine metabolism and inflammation affect global DNA methylation in early liver disease

PubMed Central

Medici, Valentina; Shibata, Noreene M.; Kharbanda, Kusum K.; LaSalle, Janine M.; Woods, Rima; Liu, Sarah; Engelberg, Jesse A.; Devaraj, Sridevi; Török, Natalie J.; Jiang, Joy X.; Havel, Peter J.; Lönnerdal, Bo; Kim, Kyoungmi; Halsted, Charles H.

2012-01-01

Hepatic methionine metabolism may play an essential role in regulating methylation status and liver injury in Wilson disease (WD) through the inhibition of S-adenosylhomocysteine hydrolase (SAHH) by copper (Cu) and the consequent accumulation of S-adenosylhomocysteine (SAH). We studied the transcript levels of selected genes related to liver injury, levels of SAHH, SAH, DNA methyltransferases genes (Dnmt1, Dnmt3a, Dnmt3b) and global DNA methylation in the tx-j mouse (tx-j), an animal model of WD. Findings were compared to those in control C3H mice, and in response to Cu chelation by penicillamine (PCA) and dietary supplementation of the methyl donor betaine to modulate inflammatory and methylation status. Transcript levels of selected genes related to endoplasmic reticulum stress, lipid synthesis, and fatty acid oxidation were down-regulated at baseline in tx-j mice, further down-regulated in response to PCA, and showed little to no response to betaine. Hepatic Sahh transcript and protein levels were reduced in tx-j mice with consequent increase of SAH levels. Hepatic Cu accumulation was associated with inflammation, as indicated by histopathology and elevated serum ALT and liver tumor necrosis factor alpha (Tnf-α) levels. Dnmt3b was down-regulated in tx-j mice together with global DNA hypomethylation. PCA treatment of tx-j mice reduced Tnf-α and ALT levels, betaine treatment increased S-adenosylmethionine and up-regulated Dnmt3b levels, and both treatments restored global DNA methylation levels. Conclusion: reduced hepatic Sahh expression was associated with increased liver SAH levels in the tx-j model of WD, with consequent global DNA hypomethylation. Increased global DNA methylation was achieved by reducing inflammation by Cu chelation or by providing methyl groups. We propose that increased SAH levels and inflammation affect widespread epigenetic regulation of gene expression in WD. PMID:22945834

Fatty Acid β-Oxidation Is Essential in Leptin-Mediated Oocytes Maturation of Yellow Catfish Pelteobagrus fulvidraco.

PubMed

Song, Yu-Feng; Tan, Xiao-Ying; Pan, Ya-Xiong; Zhang, Li-Han; Chen, Qi-Liang

2018-05-14

Although several studies have been conducted to study leptin function, information is very scarce on the molecular mechanism of leptin in fatty acid β-oxidation and oocytes maturation in fish. In this study, we investigated the potential role of fatty acid β-oxidation in leptin-mediated oocytes maturation in Pelteobagrus fulvidraco . Exp. 1 investigated the transcriptomic profiles of ovary and the differential expression of genes involved in β-oxidation and oocytes maturation following rt-hLEP injection; rt-hLEP injection was associated with significant changes in the expression of genes, including twenty-five up-regulated genes ( CPT1 , Acsl , Acadl , Acadm , Hadhb , Echsl , Hsd17b4 , Acca , PPARα , CYP8B1 , ACOX1 , ACBP , MAPK , RINGO , Cdc2 , MEK1 , IGF-1R , APC/C, Cdk2 , GnRHR, STAG3 , SMC1 , FSHβ and C-Myc ) and ten down-regulated gene ( PPARγ , FATCD36 , UBC , PDK1 , Acads , Raf , Fizzy , C3H-4 , Raf and PKC ), involved in fatty acid β-oxidation and oocytes maturation. In Exp. 2, rt-hLEP and specific inhibitors AG490 (JAK-STAT inhibitor) were used to explore whether leptin induced oocytes maturation, and found that leptin incubation increased the diameters of oocytes and percentage of germinal vesicle breakdown (GVBD)-MII oocytes, up-regulated mRNA levels of genes involved in oocytes maturation and that leptin-induced oocyte maturation was related to activation of JAK-STAT pathway. In Exp. 3, primary oocytes of P. fulvidraco were treated with (R)-(+)-etomoxir (an inhibitor of β-oxidation) or l-carnitine (an enhancer of β-oxidation) for 48 h under rt-hLEP incubation. Exp. 3 indicated that the inhibition of fatty acid β-oxidation resulted in the down-regulation of gene expression involved in oocytes maturation, and repressed the leptin-induced up-regulation of these gene expression. Activation of fatty acid β-oxidation improved the maturation rate and mean diameter of oocytes, and up-regulated gene expression involved in oocytes maturation. Leptin is one of the main factors that links fatty acid β-oxidation with oocyte maturation; β-oxidation is essential for leptin-mediated oocyte maturation in fish.

MiR-29b inhibits collagen maturation in hepatic stellate cells through down-regulating the expression of HSP47 and lysyl oxidase

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

Zhang, Yifei; Ghazwani, Mohammed; Li, Jiang

Highlights: • Enhanced HSP47 and LOX expression is associated with decreased miR-29b level in liver fibrosis. • miR-29b down-regulates HSP47 and LOX expression. • The suppression of HSP47 and LOX by miR-29b is mediated by putative sites at their 3′-UTRs. • miR-29b inhibits extracellular LOX activity and collagen maturation. - Abstract: Altered expression of miR-29b is implicated in the pathogenesis and progression of liver fibrosis. We and others previously demonstrated that miR-29b down-regulates the expression of several extracellular-matrix (ECM) genes including Col 1A1, Col 3A1 and Elastin via directly targeting their 3′-UTRs. However, whether or not miR-29b plays a rolemore » in the post-translational regulation of ECM biosynthesis has not been reported. Heat shock protein 47 (HSP47) and lysyl oxidase (LOX) are known to be essential for ECM maturation. In this study we have demonstrated that expression of HSP47 and LOX was significantly up-regulated in culture-activated primary rat hepatic stellate cells (HSCs), TGF-β stimulated LX-2 cells and liver tissue of CCl{sub 4}-treated mice, which was accompanied by a decrease of miR-29b level. In addition, over-expression of miR-29b in LX-2 cells resulted in significant inhibition on HSP47 and LOX expression. Mechanistically, miR-29b inhibited the expression of a reporter gene that contains the respective full-length 3′-UTR from HSP47 and LOX gene, and this inhibitory effect was abolished by the deletion of a putative miR-29b targeting sequence from the 3′-UTRs. Transfection of LX-2 cells with miR-29b led to abnormal collagen structure as shown by electron-microscopy, presumably through down-regulation of the expression of molecules involved in ECM maturation including HSP47 and LOX. These results demonstrated that miR-29b is involved in regulating the post-translational processing of ECM and fibril formation.« less

mTOR up-regulation of PFKFB3 is essential for acute myeloid leukemia cell survival

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

Feng, Yonghuai; Institute of Hematology, Peking University, Beijing; Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, Beijing

Although mTOR (mammalian target of rapamycin) activation is frequently observed in acute myeloid leukemia (AML) patients, the precise function and the downstream targets of mTOR are poorly understood. Here we revealed that PFKFB3, but not PFKFB1, PFKFB2 nor PFKFB4 was a novel downstream substrate of mTOR signaling pathway as PFKFB3 level was augmented after knocking down TSC2 in THP1 and OCI-AML3 cells. Importantly, PFKFB3 silencing suppressed glycolysis and cell proliferation of TSC2 silencing OCI-AML3 cells and activated apoptosis pathway. These results suggested that mTOR up-regulation of PFKFB3 was essential for AML cells survival. Mechanistically, Rapamycin treatment or Raptor knockdown reducedmore » the expression of PFKFB3 in TSC2 knockdown cells, while Rictor silencing did not have such effect. Furthermore, we also revealed that mTORC1 up-regulated PFKFB3 was dependent on hypoxia-inducible factor 1α (HIF1α), a positive regulator of glycolysis. Moreover, PFKFB3 inhibitor PFK15 and rapamycin synergistically blunted the AML cell proliferation. Taken together, PFKFB3 was a promising drug target in AML patients harboring mTOR hyper-activation.« less

A heteromeric potassium channel involved in the modulation of the plasma membrane potential is essential for the survival of African trypanosomes.

PubMed

Steinmann, Michael E; González-Salgado, Amaia; Bütikofer, Peter; Mäser, Pascal; Sigel, Erwin

2015-08-01

Discovery of novel drug targets may lead to improved treatment of trypanosomiasis. We characterize here 2 gene products of Trypanosoma brucei that are essential for the growth of bloodstream form (BSF) parasites, as shown by RNA interference (RNAi)-mediated down-regulation of the individual mRNAs. The primary sequences of the 2 proteins--protein encoded by gene Tb927.1.4450 (TbK1) and protein encoded by gene Tb927.9.4820 (TbK2)--indicate that both belong to the family of putative, Ca(2+)-activated potassium channels. The proteins were expressed in Xenopus laevis oocytes and their functions investigated by use of electrophysiological techniques. Only combined expression of TbK1 and TbK2 results in the formation of sizeable currents, indicating that these proteins probably assemble into a heteromeric ion channel. The current mediated by this channel shows little time and voltage dependence and displays a permeability ratio of K(+)/Na(+) of >20. The known potassium channel blocker barium inhibits this channel with a half-maximal inhibitory concentration (IC50) of 98 ± 15 μM. The membrane potential of trypanosomes was measured with a fluorescent dye. Individual RNAi-mediated down-regulation of TbK1 or TbK2 eliminates a potassium conductance in the plasma membrane of BSF. Thus, this heteromeric potassium channel is involved in the modulation of the plasma membrane potential and represents a novel drug target in T. brucei. © FASEB.

Ubiquitination by the Membrane-associated RING-CH-8 (MARCH-8) Ligase Controls Steady-state Cell Surface Expression of Tumor Necrosis Factor-related Apoptosis Inducing Ligand (TRAIL) Receptor 1*

PubMed Central

van de Kooij, Bert; Verbrugge, Inge; de Vries, Evert; Gijsen, Merel; Montserrat, Veronica; Maas, Chiel; Neefjes, Jacques; Borst, Jannie

2013-01-01

The eleven members of the membrane-associated RING-CH (MARCH) ubiquitin ligase family are relatively unexplored. Upon exogenous (over)expression, a number of these ligases can affect the trafficking of membrane molecules. However, only for MARCH-1 endogenous functions have been demonstrated. For the other endogenous MARCH proteins, no functions or substrates are known. We report here that TRAIL-R1 is a physiological substrate of the endogenous MARCH-8 ligase. Human TRAIL-R1 and R2 play a role in immunosurveillance and are targets for cancer therapy, because they selectively induce apoptosis in tumor cells. We demonstrate that TRAIL-R1 is down-regulated from the cell surface, with great preference over TRAIL-R2, by exogenous expression of MARCH ligases that are implicated in endosomal trafficking, such as MARCH-1 and -8. MARCH-8 attenuated TRAIL-R1 cell surface expression and apoptosis signaling by virtue of its ligase activity. This suggested that ubiquitination of TRAIL-R1 was instrumental in its down-regulation by MARCH-8. Indeed, in cells with endogenous MARCH expression, TRAIL-R1 was ubiquitinated at steady-state, with the conserved membrane-proximal lysine 273 as one of the potential acceptor sites. This residue was also essential for the interaction of TRAIL-R1 with MARCH-1 and MARCH-8 and its down-regulation by these ligases. Gene silencing identified MARCH-8 as the endogenous ligase that ubiquitinates TRAIL-R1 and attenuates its cell surface expression. These findings reveal that endogenous MARCH-8 regulates the steady-state cell surface expression of TRAIL-R1. PMID:23300075

Phosphorylation of a conserved Thr357 in yeast Nedd4-like ubiquitin ligase Rsp5 is involved in down-regulation of the general amino acid permease Gap1.

PubMed

Sasaki, Toshiya; Takagi, Hiroshi

2013-06-01

Rsp5, an essential HECT-type ubiquitin ligase, is the only yeast Saccharomyces cerevisiae member of the Nedd4 family. Rsp5 triggers the ubiquitination-dependent endocytosis of the general amino acid permease Gap1 in response to a good nitrogen source. Previously, we showed that the Thr357Ala/Lys764Glu variant Rsp5 induces the constitutive inactivation of Gap1, which is mainly involved in uptake of the toxic proline analogue, l-azetidine-2-carboxylate (AZC). Here, our experimental results indicated that the Thr357Ala substitution in the substrate-recognizing WW2 domain of Rsp5 constitutively causes the down-regulation of four proline permeases (Gap1, Put4, Agp1 and Gnp1), leading to AZC tolerance to yeast cells. In RSP5(T357A) cells, Gap1 was highly ubiquitinated and constantly delivered to the vacuole from the Golgi without sorting to the plasma membrane. Analyses of RSP5 mutants using antiphosphopeptide antibody suggest that Thr phosphorylation occurred in all three WW domains and, interestingly, that Thr357 in the WW2 domain was phosphorylated, in agreement with the in vitro result for the mouse Rsp5 orthologue. Furthermore, the phosphorylation-mimic mutant (Thr357Asp) showed strong sensitivity to AZC. From these results, we propose a possible mechanism involved in the regulation of Rsp5 activity for Gap1 down-regulation via the phosphorylation of a conserved Thr357 in the Nedd4 family. © 2013 The Authors Genes to Cells © 2013 by the Molecular Biology Society of Japan and Wiley Publishing Asia Pty Ltd.

The Arabidopsis microtubule-associated protein MAP65-3 supports infection by filamentous biotrophic pathogens by down-regulating salicylic acid-dependent defenses.

PubMed

Quentin, Michaël; Baurès, Isabelle; Hoefle, Caroline; Caillaud, Marie-Cécile; Allasia, Valérie; Panabières, Franck; Abad, Pierre; Hückelhoven, Ralph; Keller, Harald; Favery, Bruno

2016-03-01

The oomycete Hyaloperonospora arabidopsidis and the ascomycete Erysiphe cruciferarum are obligate biotrophic pathogens causing downy mildew and powdery mildew, respectively, on Arabidopsis. Upon infection, the filamentous pathogens induce the formation of intracellular bulbous structures called haustoria, which are required for the biotrophic lifestyle. We previously showed that the microtubule-associated protein AtMAP65-3 plays a critical role in organizing cytoskeleton microtubule arrays during mitosis and cytokinesis. This renders the protein essential for the development of giant cells, which are the feeding sites induced by root knot nematodes. Here, we show that AtMAP65-3 expression is also induced in leaves upon infection by the downy mildew oomycete and the powdery mildew fungus. Loss of AtMAP65-3 function in the map65-3 mutant dramatically reduced infection by both pathogens, predominantly at the stages of leaf penetration. Whole-transcriptome analysis showed an over-represented, constitutive activation of genes involved in salicylic acid (SA) biosynthesis, signaling, and defense execution in map65-3, whereas jasmonic acid (JA)-mediated signaling was down-regulated. Preventing SA synthesis and accumulation in map65-3 rescued plant susceptibility to pathogens, but not the developmental phenotype caused by cytoskeleton defaults. AtMAP65-3 thus has a dual role. It positively regulates cytokinesis, thus plant growth and development, and negatively interferes with plant defense against filamentous biotrophs. Our data suggest that downy mildew and powdery mildew stimulate AtMAP65-3 expression to down-regulate SA signaling for infection. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Proteomic analysis of mouse thymoma EL4 cells treated with bis(tri-n-butyltin)oxide (TBTO).

PubMed

Osman, Ahmed M; van Kol, Sandra; Peijnenburg, Ad; Blokland, Marco; Pennings, Jeroen L A; Kleinjans, Jos C S; van Loveren, Henk

2009-09-01

Here, we report the results of proteomic analysis of the mouse thymoma EL4 cell line exposed to bis(tri-n-butylin)oxide (TBTO), an immunotoxic organotin compound. The objective of the work was to examine whether TBTO affects the expression of proteins in this cell line and to compare the differentially expressed proteins with the corresponding mRNA expression data. The identified proteins were quantified using a label-free quantitative method based on counting the observed peptides as an index of protein abundance. The calculation of the ratio of peptides obtained from exposed and control samples allowed us to evaluate the effect of TBTO on protein expression and to compare these results to those obtained in gene expression profiling studies. Correlation of some of the differentially expressed proteins and their corresponding mRNAs was observed. The analysis of the protein ratios revealed that 12 proteins were significantly affected. These proteins included cytoskeleton proteins myosin-9, spectrin beta 2 and plectin 8. The first two proteins were down-regulated 3-fold, whereas the third was up-regulated 2-fold. Ras-related Rab1, a GTP binding protein and T-complex protein-1 subunit alpha, a chaperonin, were decreased 2- and 3.6-fold, respectively. The ribosomal S10 and eukaryotic translation factor (eIf4G1), which are involved in protein synthesis, were down-regulated 2.6- and 3.7-fold, respectively. Also, proteins involved in splicing of pre-mRNA and in transcription, splicing factor arginine/serine-rich 2 and chromodomain-helicase-DNA binding protein 4 (Chd4), were decreased 2.6- and 4.5 times, respectively. Nuclear RNA helicase II was reduced 2.8-fold. Finally, prothymosin-alpha (ProTalpha), an essential protein for cell proliferation, and a protein similar to ProTalpha, (with a molecular weight and a pI (3.54) comparable to that of ProTalpha) were also down-regulated 6-and 8-fold, respectively. We propose that the observed down-regulation of the expression level of ProTalpha in the TBTO-exposed cells could account for the previously reported anti-proliferative effect of TBTO.

Syndecan-1 knock-down in decidualized human endometrial stromal cells leads to significant changes in cytokine and angiogenic factor expression patterns

PubMed Central

2010-01-01

Background Successful embryonic implantation depends on a synchronized embryo-maternal dialogue. Chemokines, such as chemokine ligand 1 (CXCL1), play essential roles in the maternal reproductive tract leading to morphological changes during decidualization, mediating maternal acceptance towards the semi-allograft embryo and induction of angiogenesis. Chemokine binding to their classical G-protein coupled receptors is essentially supported by the syndecan (Sdc) family of heparan sulfate proteoglycans. The aim of this study was to identify the involvement of Sdc-1 at the embryo-maternal interface regarding changes of the chemokine and angiogenic profile of the decidua during the process of decidualization and implantation in human endometrium. Methods A stable Sdc-1 knock-down was generated in the immortalized human endometrial stromal cell line St-T1 and was named KdS1. The ability of KdS1 to decidualize was proven by Insulin-like growth factor binding 1 (IGFBP1) and prolactin (PRL) confirmation on mRNA level before further experiments were carried out. Dot blot protein analyses of decidualized knock-down cells vs non-transfected controls were performed. In order to imitate embryonic implantation, decidualized KdS1 were then incubated with IL-1beta, an embryo secretion product, vs controls. Statistical analyses were performed applying the Student's t-test with p < 0.05, p < 0.02 and p < 0.01 and one way post-hoc ANOVA test with p < 0.05 as cut-offs for statistical significance. Results The induction of the Sdc-1 knock-down revealed significant changes in cytokine and angiogenic factor expression profiles of dKdS1 vs decidualized controls. Incubation with embryonic IL-1beta altered the expression patterns of KdS1 chemokines and angiogenic factors towards inflammatory-associated molecules and factors involved in matrix regulation. Conclusions Sdc-1 knock-down in human endometrial stroma cells led to fulminant changes regarding cytokine and angiogenic factor expression profiles upon decidualization and imitation of embryonic contact. Sdc-1 appears to play an important role as a co-receptor and storage factor for many cytokines and angiogenic factors during decidualization and implantation period, supporting proper implantation and angiogenesis by regulation of chemokine and angiogenic factor secretion in favour of the implanting embryo. PMID:21044331

Effect of TAK1 on osteogenic differentiation of mesenchymal stem cells by regulating BMP-2 via Wnt/β-catenin and MAPK pathway.

PubMed

Yang, Hongpeng; Guo, Yue; Wang, Dawei; Yang, Xiaofei; Ha, Chengzhi

2018-01-02

Mesenchymal stem cells (MSCs) have the ability to differentiate into osteoblasts and chondrocytes. In vitro osteogenic differentiation is critical but the molecular mechanism has yet to be further clarified. The role of TGF-β activated kinase 1 (TAK1) in MSCs osteogenesis differentiation has not been reported. By adding si-TAK1 and rhTAK1, the osteogenic differentiation of MSCs was measured. Expression levels of the osteoblastic marker genes during osteogenic differentiation of MSCs were checked. As well as molecules involved in BMP and Wnt/β-catenin signaling pathways. The phosphorylation of p38 and JNK was also checked. TAK1 is essential for mineralization of MSCs at low concentration, but excessive rhTAK1 inhibits mineralization of MSCs. It up regulates the expression levels of bone sialoprotein (BSP), osteocalcin (OSC), Alkaline phosphatase (ALP), and RUNX2 during osteogenic differentiation of MSCs. It can also promote TGF-β/BMP-2 gene expression and β-catenin expression, and down regulate GSK-3β expression. Meanwhile, TAK1 promotes the phosphorylation of p38 and JNK. Additionally, TAK1 up regulates the expression of BMP-2 at all concentration under the inhibition of p38 and JNK. Our results suggested that TAK1 is essential in MSCs osteogenesis differentiation, and functions as a double-edged sword, probably through regulation of β-catenin and p38/JNK.

The Murine Ortholog of Notchless, a Direct Regulator of the Notch Pathway in Drosophila melanogaster, Is Essential for Survival of Inner Cell Mass Cells

PubMed Central

Cormier, Sarah; Le Bras, Stéphanie; Souilhol, Céline; Vandormael-Pournin, Sandrine; Durand, Béatrice; Babinet, Charles; Baldacci, Patricia; Cohen-Tannoudji, Michel

2006-01-01

Notch signaling is an evolutionarily conserved pathway involved in intercellular communication and is essential for proper cell fate choices. Numerous genes participate in the modulation of the Notch signaling pathway activity. Among them, Notchless (Nle) is a direct regulator of the Notch activity identified in Drosophila melanogaster. Here, we characterized the murine ortholog of Nle and demonstrated that it has conserved the ability to modulate Notch signaling. We also generated mice deficient for mouse Nle (mNle) and showed that its disruption resulted in embryonic lethality shortly after implantation. In late mNle−/− blastocysts, inner cell mass (ICM) cells died through a caspase 3-dependent apoptotic process. Most deficient embryos exhibited a delay in the temporal down-regulation of Oct4 expression in the trophectoderm (TE). However, mNle-deficient TE was able to induce decidual swelling in vivo and properly differentiated in vitro. Hence, our results indicate that mNle is mainly required in ICM cells, being instrumental for their survival, and raise the possibility that the death of mNle-deficient embryos might result from abnormal Notch signaling during the first steps of development. PMID:16611995

The murine ortholog of notchless, a direct regulator of the notch pathway in Drosophila melanogaster, is essential for survival of inner cell mass cells.

PubMed

Cormier, Sarah; Le Bras, Stéphanie; Souilhol, Céline; Vandormael-Pournin, Sandrine; Durand, Béatrice; Babinet, Charles; Baldacci, Patricia; Cohen-Tannoudji, Michel

2006-05-01

Notch signaling is an evolutionarily conserved pathway involved in intercellular communication and is essential for proper cell fate choices. Numerous genes participate in the modulation of the Notch signaling pathway activity. Among them, Notchless (Nle) is a direct regulator of the Notch activity identified in Drosophila melanogaster. Here, we characterized the murine ortholog of Nle and demonstrated that it has conserved the ability to modulate Notch signaling. We also generated mice deficient for mouse Nle (mNle) and showed that its disruption resulted in embryonic lethality shortly after implantation. In late mNle(-/-) blastocysts, inner cell mass (ICM) cells died through a caspase 3-dependent apoptotic process. Most deficient embryos exhibited a delay in the temporal down-regulation of Oct4 expression in the trophectoderm (TE). However, mNle-deficient TE was able to induce decidual swelling in vivo and properly differentiated in vitro. Hence, our results indicate that mNle is mainly required in ICM cells, being instrumental for their survival, and raise the possibility that the death of mNle-deficient embryos might result from abnormal Notch signaling during the first steps of development.

A lignin-specific peroxidase in tobacco whose antisense suppression leads to vascular tissue modification

NASA Technical Reports Server (NTRS)

Blee, Kristopher A.; Choi, Joon W.; O'Connell, Ann P.; Schuch, Wolfgang; Lewis, Norman G.; Bolwell, G. Paul

2003-01-01

A tobacco peroxidase isoenzyme (TP60) was down-regulated in tobacco using an antisense strategy, this affording transformants with lignin reductions of up to 40-50% of wild type (control) plants. Significantly, both guaiacyl and syringyl levels decreased in essentially a linear manner with the reductions in lignin amounts, as determined by both thioacidolysis and nitrobenzene oxidative analyses. These data provisionally suggest that a feedback mechanism is operative in lignifying cells, which prevents build-up of monolignols should oxidative capacity for their subsequent metabolism be reduced. Prior to this study, the only known rate-limiting processes in the monolignol/lignin pathways involved that of Phe supply and the relative activities of cinnamate-4-hydroxylase/p-coumarate-3-hydroxylase, respectively. These transformants thus provide an additional experimental means in which to further dissect and delineate the factors involved in monolignol targeting to precise regions in the cell wall, and of subsequent lignin assembly. Interestingly, the lignin down-regulated tobacco phenotypes displayed no readily observable differences in overall growth and development profiles, although the vascular apparatus was modified.

Differential lactate and cholesterol synthetic activities in XY and XX Sertoli cells.

PubMed

Shishido, Yurina; Baba, Takashi; Sato, Tetsuya; Shima, Yuichi; Miyabayashi, Kanako; Inoue, Miki; Akiyama, Haruhiko; Kimura, Hiroshi; Kanai, Yoshiakira; Ishihara, Yasuhiro; Haraguchi, Shogo; Miyazaki, Akira; Rozman, Damjana; Yamazaki, Takeshi; Choi, Man-Ho; Ohkawa, Yasuyuki; Suyama, Mikita; Morohashi, Ken-Ichirou

2017-02-02

SRY, a sex-determining gene, induces testis development in chromosomally female (XX) individuals. However, mouse XX Sertoli cells carrying Sry (XX/Sry Sertoli cells) are incapable of fully supporting germ cell development, even when the karyotype of the germ cells is XY. While it has therefore been assumed that XX/Sry Sertoli cells are not functionally equivalent to XY Sertoli cells, it has remained unclear which specific functions are affected. To elucidate the functional difference, we compared the gene expression of XY and XX/Sry Sertoli cells. Lactate and cholesterol metabolisms, essential for nursing the developing germ cells, were down-regulated in XX/Sry cells, which appears to be caused at least in part by the differential expression of histone modification enzymes SMCX/SMCY (H3K4me3 demethylase) and UTX/UTY (H3K27me3 demethylase) encoded by the sex chromosomes. We suggest that down-regulation of lactate and cholesterol metabolism that may be due to altered epigenetic modification affects the nursing functions of XX/Sry Sertoli cells.

Differential lactate and cholesterol synthetic activities in XY and XX Sertoli cells

PubMed Central

Shishido, Yurina; Baba, Takashi; Sato, Tetsuya; Shima, Yuichi; Miyabayashi, Kanako; Inoue, Miki; Akiyama, Haruhiko; Kimura, Hiroshi; Kanai, Yoshiakira; Ishihara, Yasuhiro; Haraguchi, Shogo; Miyazaki, Akira; Rozman, Damjana; Yamazaki, Takeshi; Choi, Man-Ho; Ohkawa, Yasuyuki; Suyama, Mikita; Morohashi, Ken-ichirou

2017-01-01

SRY, a sex-determining gene, induces testis development in chromosomally female (XX) individuals. However, mouse XX Sertoli cells carrying Sry (XX/Sry Sertoli cells) are incapable of fully supporting germ cell development, even when the karyotype of the germ cells is XY. While it has therefore been assumed that XX/Sry Sertoli cells are not functionally equivalent to XY Sertoli cells, it has remained unclear which specific functions are affected. To elucidate the functional difference, we compared the gene expression of XY and XX/Sry Sertoli cells. Lactate and cholesterol metabolisms, essential for nursing the developing germ cells, were down-regulated in XX/Sry cells, which appears to be caused at least in part by the differential expression of histone modification enzymes SMCX/SMCY (H3K4me3 demethylase) and UTX/UTY (H3K27me3 demethylase) encoded by the sex chromosomes. We suggest that down-regulation of lactate and cholesterol metabolism that may be due to altered epigenetic modification affects the nursing functions of XX/Sry Sertoli cells. PMID:28150810

Amitriptyline down-regulates coenzyme Q10 biosynthesis in lung cancer cells.

PubMed

Ortiz, Tamara; Villanueva-Paz, Marina; Díaz-Parrado, Eduardo; Illanes, Matilde; Fernández-Rodríguez, Ana; Sánchez-Alcázar, José A; de Miguel, Manuel

2017-02-15

Amitriptyline, a tricyclic antidepressant, has been proposed as an antitumoral drug in oxidative therapy. Its pro-apoptotic effects, mediated by high reactive oxygen species generation, have been already described. In this study we analysed the effect of amitriptyline on the biosynthesis of coenzyme Q 10 (CoQ), an essential component for electron transport and a potent membrane antioxidant involved in redox signaling. We treated H460 cells, a non-small-cell lung cancer cell line, with amitriptyline and we analysed CoQ levels by HPLC and CoQ biosynthesis rate, as well as the enzymes involved in CoQ biosynthesis by real-time PCR and Western blot. Amitriptyline treatment induced a dose-dependent decrease in CoQ levels in tumor cells. CoQ decreased levels were associated with down-regulation of the expression of COQ4 gene, as well as decreased Coq4 and Coq6 protein levels. Our findings suggest that the effect of amitriptyline on CoQ biosynthesis highlights the potential of this drug for antitumoral oxidative therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

4-1BB regulates NKG2D costimulation in human cord blood CD8+ T cells.

PubMed

Kim, Young-June; Han, Myung-Kwan; Broxmeyer, Hal E

2008-02-01

Ligation of NKG2D, a potent costimulatory receptor, can be either beneficial or detrimental to CD8(+) cytotoxic T cell (CTL) responses. Factors for these diverse NKG2D effects remain elusive. In this study, we demonstrate that 4-1BB, another costimulatory receptor, is an essential regulator of NKG2D in CD8(+) T cells. Costimulation of NKG2D caused down-modulation of NKG2D, but induced 4-1BB expression on the cell surface, even in the presence of TGF-beta1, which inhibits 4-1BB expression. Resulting NKG2D(-)4-1BB(+) cells were activated but still in an immature state with low cytotoxic activity. However, subsequent 4-1BB costimulation induced cytotoxic activity and restored down-modulated NKG2D. The cytotoxic activity and NKG2D expression induced by 4-1BB on NKG2D(+)4-1BB(+) cells were refractory to TGF-beta1 down-modulation. Such 4-1BB effects were enhanced by IL-12. In contrast, in the presence of IL-4, 4-1BB effects were abolished because IL-4 down-modulated NKG2D and 4-1BB expression in cooperation with TGF-beta1, generating another CD8(+) T-cell type lacking both NKG2D and 4-1BB. These NKG2D(-)4-1BB(-) cells were inert and unable to gain cytotoxic activity. Our results suggest that 4-1BB plays a critical role in protecting NKG2D from TGF-beta1-mediated down-modulation. Co-expression of NKG2D and 4-1BB may represent an important biomarker for defining competency of tumor infiltrating CD8(+) T cells.

Effects of High Hydrostatic Pressure on Expression Profiles of In Vitro Produced Vitrified Bovine Blastocysts

PubMed Central

Jiang, Zongliang; Harrington, Patrick; Zhang, Ming; Marjani, Sadie L.; Park, Joonghoon; Kuo, Lynn; Pribenszky, Csaba; Tian, Xiuchun (Cindy)

2016-01-01

High hydrostatic pressure (HHP) has been used to pre-condition embryos before essential, yet potentially detrimental procedures such as cryopreservation. However, the mechanisms for HHP are poorly understood. We treated bovine blastocysts with three different HHP (40, 60 and 80 MPa) in combination with three recovery periods (0, 1 h, 2 h post HHP). Re-expansion rates were significantly higher at 40 and 60 but lower at 80 MPa after vitrification-warming in the treated groups than controls. Microarray analysis revealed 399 differentially expressed transcripts, representing 254 unique genes, among different groups. Gene ontology analysis indicated that HHP at 40 and 60 MPa promoted embryo competence through down-regulation of genes in cell death and apoptosis, and up-regulation of genes in RNA processing, cellular growth and proliferation. In contrast, 80 MPa up-regulated genes in apoptosis, and down-regulated protein folding and cell cycle-related genes. Moreover, gene expression was also influenced by the length of the recovery time after HHP. The significantly over-represented categories were apoptosis and cell death in the 1 h group, and protein folding, response to unfolded protein and cell cycle in the 2 h group compared to 0 h. Taken together, HHP promotes competence of vitrified bovine blastocysts through modest transcriptional changes. PMID:26883277

The AtRbx1 protein is part of plant SCF complexes, and its down-regulation causes severe growth and developmental defects.

PubMed

Lechner, Esther; Xie, Daoxin; Grava, Sandrine; Pigaglio, Emmanuelle; Planchais, Severine; Murray, James A H; Parmentier, Yves; Mutterer, Jerome; Dubreucq, Bertrand; Shen, Wen-Hui; Genschik, Pascal

2002-12-20

Recently in yeast and animal cells, one particular class of ubiquitin ligase (E3), called the SCF, was demonstrated to regulate diverse processes including cell cycle and development. In plants SCF-dependent proteolysis is also involved in different developmental and hormonal regulations. To further investigate the function of SCF, we characterized at the molecular level the Arabidopsis RING-H2 finger protein AtRbx1. We demonstrated that the plant gene is able to functionally complement a yeast knockout mutant strain and showed that AtRbx1 protein interacts physically with at least two members of the Arabidopsis cullin family (AtCul1 and AtCul4). AtRbx1 also associates with AtCul1 and the Arabidopsis SKP1-related proteins in planta, indicating that it is part of plant SCF complexes. AtRbx1 mRNAs accumulate in various tissues of the plant, but at higher levels in tissues containing actively dividing cells. Finally to study the function of the gene in planta, we either overexpressed AtRbx1 or reduced its expression by a dsRNA strategy. Down-regulation of AtRbx1 impaired seedling growth and development, indicating that the gene is essential in plants. Furthermore, the AtRbx1-silenced plants showed a reduced level of AtCul1 protein, but accumulated higher level of cyclin D3.

RNA-seq methods for identifying differentially expressed gene in human pancreatic islet cells treated with pro-inflammatory cytokines.

PubMed

Li, Bo; Bi, Chang Long; Lang, Ning; Li, Yu Ze; Xu, Chao; Zhang, Ying Qi; Zhai, Ai Xia; Cheng, Zhi Feng

2014-01-01

Type 1 diabetes is a chronic autoimmune disease in which pancreatic beta cells are killed by the infiltrating immune cells as well as the cytokines released by these cells. Many studies indicate that inflammatory mediators have an essential role in this disease. In the present study, we profiled the transcriptome in human islets of langerhans under control conditions or following exposure to the pro-inflammatory cytokines based on the RNA sequencing dataset downloaded from SRA database. After filtered the low-quality ones, the RNA readers was aligned to human genome hg19 by TopHat and then assembled by Cufflinks. The expression value of each transcript was calculated and consequently differentially expressed genes were screened out. Finally, a total of 63 differentially expressed genes were identified including 60 up-regulated and three down-regulated genes. GBP5 and CXCL9 stood out as the top two most up-regulated genes in cytokines treated samples with the log2 fold change of 12.208 and 10.901, respectively. Meanwhile, PTF1A and REG3G were identified as the top two most down-regulated genes with the log2 fold change of -3.759 and -3.606, respectively. Of note, we also found 262 lncRNAs (long non-coding RNA), 177 of which were inferred as novel lncRNAs. Further in-depth follow-up analysis of the transcriptional regulation reported in this study may shed light on the specific function of these lncRNA.

Proliferating Cell Nuclear Antigen (PCNA) Regulates Primordial Follicle Assembly by Promoting Apoptosis of Oocytes in Fetal and Neonatal Mouse Ovaries

PubMed Central

Zhang, Yuanwei; Jiang, Xiaohua; Zhang, Huan; Ma, Tieliang; Zheng, Wei; Sun, Rui; Shen, Wei; Sha, Jiahao; Cooke, Howard J.; Shi, Qinghua

2011-01-01

Primordial follicles, providing all the oocytes available to a female throughout her reproductive life, assemble in perinatal ovaries with individual oocytes surrounded by granulosa cells. In mammals including the mouse, most oocytes die by apoptosis during primordial follicle assembly, but factors that regulate oocyte death remain largely unknown. Proliferating cell nuclear antigen (PCNA), a key regulator in many essential cellular processes, was shown to be differentially expressed during these processes in mouse ovaries using 2D-PAGE and MALDI-TOF/TOF methodology. A V-shaped expression pattern of PCNA in both oocytes and somatic cells was observed during the development of fetal and neonatal mouse ovaries, decreasing from 13.5 to 18.5 dpc and increasing from 18.5 dpc to 5 dpp. This was closely correlated with the meiotic prophase I progression from pre-leptotene to pachytene and from pachytene to diplotene when primordial follicles started to assemble. Inhibition of the increase of PCNA expression by RNA interference in cultured 18.5 dpc mouse ovaries strikingly reduced the apoptosis of oocytes, accompanied by down-regulation of known pro-apoptotic genes, e.g. Bax, caspase-3, and TNFα and TNFR2, and up-regulation of Bcl-2, a known anti-apoptotic gene. Moreover, reduced expression of PCNA was observed to significantly increase primordial follicle assembly, but these primordial follicles contained fewer guanulosa cells. Similar results were obtained after down-regulation by RNA interference of Ing1b, a PCNA-binding protein in the UV-induced apoptosis regulation. Thus, our results demonstrate that PCNA regulates primordial follicle assembly by promoting apoptosis of oocytes in fetal and neonatal mouse ovaries. PMID:21253613

Selenium effect on selenoprotein transcriptome in chondrocytes.

PubMed

Yan, Jidong; Zheng, Yuewen; Min, Zixin; Ning, Qilan; Lu, Shemin

2013-04-01

Selenium is an essential micronutrient and exerts its biological functions predominantly through selenoproteins. Selenium deficiency is associated with cartilage function. This study demonstrated that all 24 selenoprotein transcripts in mouse genome were detectable in ATDC5 chondrocytes except deiodinase 1 (DIO1), DIO2, and selenoprotein V (Sel V), while all 25 selenoprotein transcripts in human genome were detectable in C28/I2 chondrocytes except glutathione peroxidase 6 (GPx6) and DIO1. In addition, gene expression of five selenoproteins (GPx1, Sel H, Sel N, Sel P, and Sel W) was up-regulated and two selenoproteins (SPS2 and Sel O) was down-regulated by sodium selenite (Se) in both ATDC5 and C28/I2 cells. Gene expression of six selenoproteins (TrxR1, Sel I, Sel M, Sel R, Sel S, Sel T) and one selenoprotein (GPx3) was up-regulated by Se in ATDC5 and C28/I2 cells, respectively. Gene expression of one selenoprotein (TrxR2) was down-regulated by Se only in ATDC5 cells. Further transcription inhibition assay showed that both transcriptional and posttranscriptional mechanisms involved in Se-regulated gene expression of GPx1, TrxR1, TrxR2, SPS2, Sel O, and Sel S. However, Se-regulated gene expression of Sel H, Sel I, Sel M, Sel N, Sel P, Sel R, Sel T, and Sel W mainly at posttranscriptional level. Moreover, new protein synthesis inhibition assay indicated that Se-mediated new protein synthesis also played roles in Se-regulated gene expression of GPx1, TrxR1, TrxR2, Sel H, Sel O, Sel P, Sel R, and Sel W. In summary, this study described the selenoprotein transcriptome, Se-regulated selenoproteins and possible mechanisms involved in chondrocytes.

Diabetic Hyperglycemia: Link to Impaired Glucose Transport in Pancreatic β Cells

NASA Astrophysics Data System (ADS)

Unger, Roger H.

1991-03-01

Glucose uptake into pancreatic β cells by means of the glucose transporter GLUT-2, which has a high Michaelis constant, is essential for the normal insulin secretory response to hyperglycemia. In both autoimmune and nonautoimmune diabetes, this glucose transport is reduced as a consequence of down-regulation of the normal β-cell transporter. In autoimmune diabetes, circulating immunoglobulins can further impair this glucose transport by inhibiting functionally intact transporters. Insights into mechanisms of the unresponsiveness of β cells to hyperglycemia may improve the management and prevention of diabetes.

P-TEFb, the Super Elongation Complex and Mediator Regulate a Subset of Non-paused Genes during Early Drosophila Embryo Development

PubMed Central

Dahlberg, Olle; Shilkova, Olga; Tang, Min; Holmqvist, Per-Henrik; Mannervik, Mattias

2015-01-01

Positive Transcription Elongation Factor b (P-TEFb) is a kinase consisting of Cdk9 and Cyclin T that releases RNA Polymerase II (Pol II) into active elongation. It can assemble into a larger Super Elongation Complex (SEC) consisting of additional elongation factors. Here, we use a miRNA-based approach to knock down the maternal contribution of P-TEFb and SEC components in early Drosophila embryos. P-TEFb or SEC depletion results in loss of cells from the embryo posterior and in cellularization defects. Interestingly, the expression of many patterning genes containing promoter-proximal paused Pol II is relatively normal in P-TEFb embryos. Instead, P-TEFb and SEC are required for expression of some non-paused, rapidly transcribed genes in pre-cellular embryos, including the cellularization gene Serendipity-α. We also demonstrate that another P-TEFb regulated gene, terminus, has an essential function in embryo development. Similar morphological and gene expression phenotypes were observed upon knock down of Mediator subunits, providing in vivo evidence that P-TEFb, the SEC and Mediator collaborate in transcription control. Surprisingly, P-TEFb depletion does not affect the ratio of Pol II at the promoter versus the 3’ end, despite affecting global Pol II Ser2 phosphorylation levels. Instead, Pol II occupancy is reduced at P-TEFb down-regulated genes. We conclude that a subset of non-paused, pre-cellular genes are among the most susceptible to reduced P-TEFb, SEC and Mediator levels in Drosophila embryos. PMID:25679530

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.

Pharmacological modulation of aversive responsiveness in honey bees

PubMed Central

Tedjakumala, Stevanus R.; Aimable, Margaux; Giurfa, Martin

2014-01-01

Within a honey bee colony, individuals performing different tasks exhibit different sensitivities to noxious stimuli. Noxious-stimulus sensitivity can be quantified in harnessed bees by measuring the sting extension response (SER) to a series of increasing voltages. Biogenic amines play a crucial role in the control of insect responsiveness. Whether or not these neurotransmitters affect the central control of aversive responsiveness, and more specifically of electric-shock responsiveness, remains unknown. Here we studied the involvement of the biogenic amines octopamine, dopamine and serotonin, and of the ecdysteroid 20-hydroxyecdisone in the central control of sting responsiveness to electric shocks. We injected pharmacological antagonists of these signaling pathways into the brain of harnessed bees and determined the effect of blocking these different forms of neurotransmission on shock responsiveness. We found that both octopamine and 20-hydroxyecdisone are dispensable for shock responsiveness while dopamine and serotonin act as down-regulators of sting responsiveness. As a consequence, antagonists of these two biogenic amines induce an increase in shock responsiveness to shocks of intermediate voltage; serotonin, can also increase non-specific responsiveness. We suggest that different classes of dopaminergic neurons exist in the bee brain and we define at least two categories: an instructive class mediating aversive labeling of conditioned stimuli in associative learning, and a global gain-control class which down-regulates responsiveness upon perception of noxious stimuli. Serotonergic signaling together with down-regulating dopaminergic signaling may play an essential role in attentional processes by suppressing responses to irrelevant, non-predictive stimuli, thereby allowing efficient behavioral performances. PMID:24431993

Arabidopsis WRKY33 Is a Key Transcriptional Regulator of Hormonal and Metabolic Responses toward Botrytis cinerea Infection1[W

PubMed Central

Birkenbihl, Rainer P.; Diezel, Celia; Somssich, Imre E.

2012-01-01

The Arabidopsis (Arabidopsis thaliana) transcription factor WRKY33 is essential for defense toward the necrotrophic fungus Botrytis cinerea. Here, we aimed at identifying early transcriptional responses mediated by WRKY33. Global expression profiling on susceptible wrky33 and resistant wild-type plants uncovered massive differential transcriptional reprogramming upon B. cinerea infection. Subsequent detailed kinetic analyses revealed that loss of WRKY33 function results in inappropriate activation of the salicylic acid (SA)-related host response and elevated SA levels post infection and in the down-regulation of jasmonic acid (JA)-associated responses at later stages. This down-regulation appears to involve direct activation of several jasmonate ZIM-domain genes, encoding repressors of the JA-response pathway, by loss of WRKY33 function and by additional SA-dependent WRKY factors. Moreover, genes involved in redox homeostasis, SA signaling, ethylene-JA-mediated cross-communication, and camalexin biosynthesis were identified as direct targets of WRKY33. Genetic studies indicate that although SA-mediated repression of the JA pathway may contribute to the susceptibility of wrky33 plants to B. cinerea, it is insufficient for WRKY33-mediated resistance. Thus, WRKY33 apparently directly targets other still unidentified components that are also critical for establishing full resistance toward this necrotroph. PMID:22392279

Progesterone down-regulates SLIT/ROBO expression in mouse corpus luteum.

PubMed

Zhang, Xuejing; Mi, Meiyan; Hao, Weili; Fan, Qiongying; Gao, Bulang

2017-09-01

Progesterone produced by the corpus luteum (CL) is essential for preparation, implantation and maintenance of gestation. Furthermore, progesterone plays a protective role against luteolysis in rodents. It has been reported that Slit/Robo family members expressed in the CL and involved in prostaglandin F 2α (PGF 2α ) induced luteolysis. However, the interactions between progesterone and Slits/Robos in CL are not clear. This study was designed to examine whether or not luteolysis is regulated by the interaction of progesterone and Slits/Robos in mouse CL. In the current study, we used Real-time PCR to identify the effect of progesterone on Slit2/Robo1 expression in cultured luteal cells in vitro, and the exogenous progesterone injection on mouse luteolysis and Slit/Robo expression in vivo was studied via Real-time PCR and Western bolt. Our in vitro experiment revealed that 1μM progesterone significantly decreased Slit2/Robo1 mRNA levels at 6h, 12h and 24h. Our in vivo experiment showed that the mRNA and protein levels of Slit2 and Robo1 decreased significantly 7days after progesterone supplement. These findings indicate that progesterone maintains CL function and resists luteolysis possibly through down-regulating Slit/Robo signaling pathway in the CL. Copyright © 2017 Elsevier GmbH. All rights reserved.

Coordinate up-regulation of low-density lipoprotein receptor and cyclo-oxygenase-2 gene expression in human colorectal cells and in colorectal adenocarcinoma biopsies

NASA Technical Reports Server (NTRS)

Lum, D. F.; McQuaid, K. R.; Gilbertson, V. L.; Hughes-Fulford, M.

1999-01-01

Many colorectal cancers have high levels of cyclo-oxygenase 2 (COX-2), an enzyme that metabolizes the essential fatty acids into prostaglandins. Since the low-density lipoprotein receptor (LDLr) is involved in the uptake of essential fatty acids, we studied the effect of LDL on growth and gene regulation in colorectal cancer cells. DiFi cells grown in lipoprotein-deficient sera (LPDS) grew more slowly than cells with LDL. LDLr antibody caused significant inhibition of tumor cell growth but did not affect controls. In addition, LDL uptake did not change in the presence of excess LDL, suggesting that ldlr mRNA lacks normal feedback regulation in some colorectal cancers. Analysis of the ldlr mRNA showed that excess LDL in the medium did not cause down-regulation of the message even after 24 hr. The second portion of the study examined the mRNA expression of ldlr and its co-regulation with cox-2 in normal and tumor specimens from patients with colorectal adenocarcinomas. The ratio of tumor:paired normal mucosa of mRNA expression of ldlr and of cox-2 was measured in specimens taken during colonoscopy. ldlr and cox-2 transcripts were apparent in 11 of 11 carcinomas. There was significant coordinate up-regulation both of ldlr and of cox-2 in 6 of 11 (55%) tumors compared with normal colonic mucosa. There was no up-regulation of cox-2 without concomitant up-regulation of ldlr. These data suggest that the LDLr is abnormally regulated in some colorectal tumors and may play a role in the up-regulation of cox-2. Copyright 1999 Wiley-Liss, Inc.

Intact mitochondrial Ca2+ uniport is essential for agonist-induced activation of endothelial nitric oxide synthase (eNOS).

PubMed

Charoensin, Suphachai; Eroglu, Emrah; Opelt, Marissa; Bischof, Helmut; Madreiter-Sokolowski, Corina T; Kirsch, Andrijana; Depaoli, Maria R; Frank, Saša; Schrammel, Astrid; Mayer, Bernd; Waldeck-Weiermair, Markus; Graier, Wolfgang F; Malli, Roland

2017-01-01

Mitochondrial Ca 2+ uptake regulates diverse endothelial cell functions and has also been related to nitric oxide (NO • ) production. However, it is not entirely clear if the organelles support or counteract NO • biosynthesis by taking up Ca 2+ . The objective of this study was to verify whether or not mitochondrial Ca 2+ uptake influences Ca 2+ -triggered NO • generation by endothelial NO • synthase (eNOS) in an immortalized endothelial cell line (EA.hy926), respective primary human umbilical vein endothelial cells (HUVECs) and eNOS-RFP (red fluorescent protein) expressing human embryonic kidney (HEK293) cells. We used novel genetically encoded fluorescent NO • probes, the geNOps, and Ca 2+ sensors to monitor single cell NO • and Ca 2+ dynamics upon cell treatment with ATP, an inositol 1,4,5-trisphosphate (IP 3 )-generating agonist. Mitochondrial Ca 2+ uptake was specifically manipulated by siRNA-mediated knock-down of recently identified key components of the mitochondrial Ca 2+ uniporter machinery. In endothelial cells and the eNOS-RFP expressing HEK293 cells we show that reduced mitochondrial Ca 2+ uptake upon the knock-down of the mitochondrial calcium uniporter (MCU) protein and the essential MCU regulator (EMRE) yield considerable attenuation of the Ca 2+ -triggered NO • increase independently of global cytosolic Ca 2+ signals. The knock-down of mitochondrial calcium uptake 1 (MICU1), a gatekeeper of the MCU, increased both mitochondrial Ca 2+ sequestration and Ca 2+ -induced NO • signals. The positive correlation between mitochondrial Ca 2+ elevation and NO • production was independent of eNOS phosphorylation at serine 1177 . Our findings emphasize that manipulating mitochondrial Ca 2+ uptake may represent a novel strategy to control eNOS-mediated NO • production. Copyright © 2016. Published by Elsevier Inc.

Microgravity and Immunity: Changes in Lymphocyte Gene Expression

NASA Technical Reports Server (NTRS)

Risin, D.; Pellis, N. R.; Ward, N. E.; Risin, S. A.

2006-01-01

Earlier studies had shown that modeled and true microgravity (MG) cause multiple direct effects on human lymphocytes. MG inhibits lymphocyte locomotion, suppresses polyclonal and antigen-specific activation, affects signal transduction mechanisms, as well as activation-induced apoptosis. In this study we assessed changes in gene expression associated with lymphocyte exposure to microgravity in an attempt to identify microgravity-sensitive genes (MGSG) in general and specifically those genes that might be responsible for the functional and structural changes observed earlier. Two sets of experiments targeting different goals were conducted. In the first set, T-lymphocytes from normal donors were activated with antiCD3 and IL2 and then cultured in 1g (static) and modeled MG (MMG) conditions (Rotating Wall Vessel bioreactor) for 24 hours. This setting allowed searching for MGSG by comparison of gene expression patterns in zero and 1 g gravity. In the second set - activated T-cells after culturing for 24 hours in 1g and MMG were exposed three hours before harvesting to a secondary activation stimulus (PHA) thus triggering the apoptotic pathway. Total RNA was extracted using the RNeasy isolation kit (Qiagen, Valencia, CA). Affymetrix Gene Chips (U133A), allowing testing for 18,400 human genes, were used for microarray analysis. In the first set of experiments MMG exposure resulted in altered expression of 89 genes, 10 of them were up-regulated and 79 down-regulated. In the second set, changes in expression were revealed in 85 genes, 20 were up-regulated and 65 were down-regulated. The analysis revealed that significant numbers of MGS genes are associated with signal transduction and apoptotic pathways. Interestingly, the majority of genes that responded by up- or down-regulation in the alternative sets of experiments were not the same, possibly reflecting different functional states of the examined T-lymphocyte populations. The responder genes (MGSG) might play an essential role in adaptation to MG and/or be responsible for pathologic changes encountered in Space and thus represent potential targets for molecular-based countermeasures

Anabaena sp. strain PCC 7120 conR contains a LytR-CpsA-Psr domain, is developmentally regulated, and is essential for diazotrophic growth and heterocyst morphogenesis.

PubMed

Mella-Herrera, Rodrigo A; Neunuebel, M Ramona; Golden, James W

2011-03-01

The conR (all0187) gene of the filamentous cyanobacterium Anabaena (Nostoc) sp. strain PCC 7120 is predicted to be part of a family of proteins that contain the LytR-CpsA-Psr domain associated with septum formation and cell wall maintenance. The conR gene was originally misannotated as a transcription regulator. Northern RNA blot analysis showed that conR expression was upregulated 8 h after nitrogen step-down. Fluorescence microscopy of a P(conR)-gfp reporter strain revealed increased GFP fluorescence in proheterocysts and heterocysts beginning 9 h after nitrogen step-down. Insertional inactivation of conR caused a septum-formation defect of vegetative cells grown in nitrate-containing medium. In nitrate-free medium, mutant filaments formed abnormally long heterocysts and were defective for diazotrophic growth. Septum formation between heterocysts and adjacent vegetative cells was abnormal, often with one or both poles of the heterocysts appearing partially open. In a conR mutant, expression of nifH was delayed after nitrogen step-down and nitrogenase activity was approximately 70 % of wild-type activity, indicating that heterocysts of the conR mutant strain are partially functional. We hypothesize that the diazotrophic growth defect is caused by an inability of the heterocysts to transport fixed nitrogen to the neighbouring vegetative cells.

Analysis of the Salmonella regulatory network suggests involvement of SsrB and H-NS in σ E-regulated SPI-2 gene expression

DOE PAGES

Li, Jie; Overall, Christopher C.; Nakayasu, Ernesto S.; ...

2015-02-10

The extracytoplasmic functioning sigma factor σ E is known to play an essential role for Salmonella enterica serovar Typhimurium to survive and proliferate in macrophages and mice. However, its regulatory network is not well characterized, especially during infection. Here we used microarray to identify genes regulated by σ E in Salmonella grown in three conditions: a nutrient-rich condition and two others that mimic early and late intracellular infection. We found that in each condition σ E regulated different sets of genes, and notably, several global regulators. When comparing nutrient-rich and infection-like conditions, large changes were observed in the expression ofmore » genes involved in Salmonella pathogenesis island (SPI)-1 type-three secretion system (TTSS), SPI-2 TTSS, protein synthesis, and stress responses. In total, the expression of 58% of Salmonella genes was affected by σ E in at least one of the three conditions. An important finding is that σ E up-regulates SPI-2 genes, which are essential for Salmonella intracellular survival, by up-regulating SPI-2 activator ssrB expression at the early stage of infection and down-regulating SPI-2 repressor hns expression at a later stage. Moreover, σ E is capable of countering the silencing of H-NS, releasing the expression of SPI-2 genes. This connection between σ E and SPI-2 genes, combined with the global regulatory effect of σ E, may account for the lethality of rpoE-deficient Salmonella in murine infection.« less

Analysis of the Salmonella regulatory network suggests involvement of SsrB and H-NS in σ E-regulated SPI-2 gene expression

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

Li, Jie; Overall, Christopher C.; Nakayasu, Ernesto S.

The extracytoplasmic functioning sigma factor σ E is known to play an essential role for Salmonella enterica serovar Typhimurium to survive and proliferate in macrophages and mice. However, its regulatory network is not well characterized, especially during infection. Here we used microarray to identify genes regulated by σ E in Salmonella grown in three conditions: a nutrient-rich condition and two others that mimic early and late intracellular infection. We found that in each condition σ E regulated different sets of genes, and notably, several global regulators. When comparing nutrient-rich and infection-like conditions, large changes were observed in the expression ofmore » genes involved in Salmonella pathogenesis island (SPI)-1 type-three secretion system (TTSS), SPI-2 TTSS, protein synthesis, and stress responses. In total, the expression of 58% of Salmonella genes was affected by σ E in at least one of the three conditions. An important finding is that σ E up-regulates SPI-2 genes, which are essential for Salmonella intracellular survival, by up-regulating SPI-2 activator ssrB expression at the early stage of infection and down-regulating SPI-2 repressor hns expression at a later stage. Moreover, σ E is capable of countering the silencing of H-NS, releasing the expression of SPI-2 genes. This connection between σ E and SPI-2 genes, combined with the global regulatory effect of σ E, may account for the lethality of rpoE-deficient Salmonella in murine infection.« less

Rosette iron deficiency transcript and microRNA profiling reveals links between copper and iron homeostasis in Arabidopsis thaliana

PubMed Central

Waters, Brian M.; Stein, Ricardo J.

2012-01-01

Iron (Fe) is an essential plant micronutrient, and its deficiency limits plant growth and development on alkaline soils. Under Fe deficiency, plant responses include up-regulation of genes involved in Fe uptake from the soil. However, little is known about shoot responses to Fe deficiency. Using microarrays to probe gene expression in Kas-1 and Tsu-1 ecotypes of Arabidopsis thaliana, and comparison with existing Col-0 data, revealed conserved rosette gene expression responses to Fe deficiency. Fe-regulated genes included known metal homeostasis-related genes, and a number of genes of unknown function. Several genes responded to Fe deficiency in both roots and rosettes. Fe deficiency led to up-regulation of Cu,Zn superoxide dismutase (SOD) genes CSD1 and CSD2, and down-regulation of FeSOD genes FSD1 and FSD2. Eight microRNAs were found to respond to Fe deficiency. Three of these (miR397a, miR398a, and miR398b/c) are known to regulate transcripts of Cu-containing proteins, and were down-regulated by Fe deficiency, suggesting that they could be involved in plant adaptation to Fe limitation. Indeed, Fe deficiency led to accumulation of Cu in rosettes, prior to any detectable decrease in Fe concentration. ccs1 mutants that lack functional Cu,ZnSOD proteins were prone to greater oxidative stress under Fe deficiency, indicating that increased Cu concentration under Fe limitation has an important role in oxidative stress prevention. The present results show that Cu accumulation, microRNA regulation, and associated differential expression of Fe and CuSOD genes are coordinated responses to Fe limitation. PMID:22962679

Dynamic range of Nef-mediated evasion of HLA class II-restricted immune responses in early HIV-1 infection.

PubMed

Mahiti, Macdonald; Brumme, Zabrina L; Jessen, Heiko; Brockman, Mark A; Ueno, Takamasa

2015-07-31

HLA class II-restricted CD4(+) T lymphocytes play an important role in controlling HIV-1 replication, especially in the acute/early infection stage. But, HIV-1 Nef counteracts this immune response by down-regulating HLA-DR and up-regulating the invariant chain associated with immature HLA-II (Ii). Although functional heterogeneity of various Nef activities, including down-regulation of HLA class I (HLA-I), is well documented, our understanding of Nef-mediated evasion of HLA-II-restricted immune responses during acute/early infection remains limited. Here, we examined the ability of Nef clones from 47 subjects with acute/early progressive infection and 46 subjects with chronic progressive infection to up-regulate Ii and down-regulate HLA-DR and HLA-I from the surface of HIV-infected cells. HLA-I down-regulation function was preserved among acute/early Nef clones, whereas both HLA-DR down-regulation and Ii up-regulation functions displayed relatively broad dynamic ranges. Nef's ability to down-regulate HLA-DR and up-regulate Ii correlated positively at this stage, suggesting they are functionally linked in vivo. Acute/early Nef clones also exhibited higher HLA-DR down-regulation and lower Ii up-regulation functions compared to chronic Nef clones. Taken together, our results support enhanced Nef-mediated HLA class II immune evasion activities in acute/early compared to chronic infection, highlighting the potential importance of these functions following transmission. Copyright © 2015 Elsevier Inc. All rights reserved.

myo-Inositol uptake is essential for bulk inositol phospholipid but not glycosylphosphatidylinositol synthesis in Trypanosoma brucei.

PubMed

Gonzalez-Salgado, Amaia; Steinmann, Michael E; Greganova, Eva; Rauch, Monika; Mäser, Pascal; Sigel, Erwin; Bütikofer, Peter

2012-04-13

myo-Inositol is an essential precursor for the production of inositol phosphates and inositol phospholipids in all eukaryotes. Intracellular myo-inositol is generated by de novo synthesis from glucose 6-phosphate or is provided from the environment via myo-inositol symporters. We show that in Trypanosoma brucei, the causative pathogen of human African sleeping sickness and nagana in domestic animals, myo-inositol is taken up via a specific proton-coupled electrogenic symport and that this transport is essential for parasite survival in culture. Down-regulation of the myo-inositol transporter using RNA interference inhibited uptake of myo-inositol and blocked the synthesis of the myo-inositol-containing phospholipids, phosphatidylinositol and inositol phosphorylceramide; in contrast, it had no effect on glycosylphosphatidylinositol production. This together with the unexpected localization of the myo-inositol transporter in both the plasma membrane and the Golgi demonstrate that metabolism of endogenous and exogenous myo-inositol in T. brucei is strictly segregated.

myo-Inositol Uptake Is Essential for Bulk Inositol Phospholipid but Not Glycosylphosphatidylinositol Synthesis in Trypanosoma brucei*

PubMed Central

Gonzalez-Salgado, Amaia; Steinmann, Michael E.; Greganova, Eva; Rauch, Monika; Mäser, Pascal; Sigel, Erwin; Bütikofer, Peter

2012-01-01

myo-Inositol is an essential precursor for the production of inositol phosphates and inositol phospholipids in all eukaryotes. Intracellular myo-inositol is generated by de novo synthesis from glucose 6-phosphate or is provided from the environment via myo-inositol symporters. We show that in Trypanosoma brucei, the causative pathogen of human African sleeping sickness and nagana in domestic animals, myo-inositol is taken up via a specific proton-coupled electrogenic symport and that this transport is essential for parasite survival in culture. Down-regulation of the myo-inositol transporter using RNA interference inhibited uptake of myo-inositol and blocked the synthesis of the myo-inositol-containing phospholipids, phosphatidylinositol and inositol phosphorylceramide; in contrast, it had no effect on glycosylphosphatidylinositol production. This together with the unexpected localization of the myo-inositol transporter in both the plasma membrane and the Golgi demonstrate that metabolism of endogenous and exogenous myo-inositol in T. brucei is strictly segregated. PMID:22351763

The Role of Sink Strength and Nitrogen Availability in the Down-Regulation of Photosynthetic Capacity in Field-Grown Nicotiana tabacum L. at Elevated CO2 Concentration.

PubMed

Ruiz-Vera, Ursula M; De Souza, Amanda P; Long, Stephen P; Ort, Donald R

2017-01-01

Down-regulation of photosynthesis is among the most common responses observed in C 3 plants grown under elevated atmospheric CO 2 concentration ([CO 2 ]). Down-regulation is often attributed to an insufficient capacity of sink organs to use or store the increased carbohydrate production that results from the stimulation of photosynthesis by elevated [CO 2 ]. Down-regulation can be accentuated by inadequate nitrogen (N) supply, which may limit sink development. While there is strong evidence for down-regulation of photosynthesis at elevated [CO 2 ] in enclosure studies most often involving potted plants, there is little evidence for this when [CO 2 ] is elevated fully under open-air field treatment conditions. To assess the importance of sink strength on the down-regulation of photosynthesis and on the potential of N to mitigate this down-regulation under agriculturally relevant field conditions, two tobacco cultivars ( Nicotiana tabacum L. cv. Petit Havana; cv. Mammoth) of strongly contrasting ability to produce the major sink of this crop, leaves, were grown under ambient and elevated [CO 2 ] and with two different N additions in a free air [CO 2 ] (FACE) facility. Photosynthetic down-regulation at elevated [CO 2 ] reached only 9% in cv. Mammoth late in the season likely reflecting sustained sink strength of the rapidly growing plant whereas down-regulation in cv. Petit Havana reached 25%. Increased N supply partially mitigated down-regulation of photosynthesis in cv. Petit Havana and this mitigation was dependent on plant developmental stage. Overall, these field results were consistent with the hypothesis that sustained sink strength, that is the ability to utilize photosynthate, and adequate N supply will allow C 3 crops in the field to maintain enhanced photosynthesis and therefore productivity as [CO 2 ] continues to rise.

Transcription of Toll-Like Receptors 2, 3, 4 and 9, FoxP3 and Th17 Cytokines in a Susceptible Experimental Model of Canine Leishmania infantum Infection

PubMed Central

Hosein, Shazia; Rodríguez-Cortés, Alhelí; Blake, Damer P.; Allenspach, Karin; Alberola, Jordi; Solano-Gallego, Laia

2015-01-01

Canine leishmaniosis (CanL) due to Leishmania infantum is a chronic zoonotic systemic disease resulting from complex interactions between protozoa and the canine immune system. Toll-like receptors (TLRs) are essential components of the innate immune system and facilitate the early detection of many infections. However, the role of TLRs in CanL remains unknown and information describing TLR transcription during infection is extremely scarce. The aim of this research project was to investigate the impact of L. infantum infection on canine TLR transcription using a susceptible model. The objectives of this study were to evaluate transcription of TLRs 2, 3, 4 and 9 by means of quantitative reverse transcription polymerase chain reaction (qRT-PCR) in skin, spleen, lymph node and liver in the presence or absence of experimental L. infantum infection in Beagle dogs. These findings were compared with clinical and serological data, parasite densities in infected tissues and transcription of IL-17, IL-22 and FoxP3 in different tissues in non-infected dogs (n = 10), and at six months (n = 24) and 15 months (n = 7) post infection. Results revealed significant down regulation of transcription with disease progression in lymph node samples for TLR3, TLR4, TLR9, IL-17, IL-22 and FoxP3. In spleen samples, significant down regulation of transcription was seen in TLR4 and IL-22 when both infected groups were compared with controls. In liver samples, down regulation of transcription was evident with disease progression for IL-22. In the skin, upregulation was seen only for TLR9 and FoxP3 in the early stages of infection. Subtle changes or down regulation in TLR transcription, Th17 cytokines and FoxP3 are indicative of the silent establishment of infection that Leishmania is renowned for. These observations provide new insights about TLR transcription, Th17 cytokines and Foxp3 in the liver, spleen, lymph node and skin in CanL and highlight possible markers of disease susceptibility in this model. PMID:26465878

Computational evaluation of new homologous down regulators of Translationally Controlled Tumor Protein (TCTP) targeted for tumor reversion.

PubMed

Nayarisseri, Anuraj; Yadav, Mukesh; Wishard, Rohan

2013-12-01

The Translationally Controlled Tumor Protein (TCTP) has been investigated for tumor reversion and is a target of cancer therapy. Down regulators which suppress the expression of TCTP can trigger the process of tumor reversion leading to the transformation of tumor cells into revertant cells. The present investigation is a novel protein-protein docking approach to target TCTP by a set of proteins similar to the protein: sorting nexin 6 (SNX6) which is an established down regulator of TCTP. The established down regulator along with its set of most similar proteins were modeled using the PYTHON based software - MODELLER v9.9, followed by structure validation using the Procheck Package. Further TCTP was docked with its established and prospective down regulators using the flexible docking protocol suite HADDOCK. The results were evaluated and ranked according to the RMSD values of the complex and the HADDOCK score, which is a weighted sum of van der Waal's energy, electrostatic energy, restraints violation energy and desolvation energy. Results concluded the protein sorting nexin 6 of Mus musculus to be a better down regulator of TCTP, as compared to the suggested down regulator (Homo sapiens snx6).

Top-down and bottom-up neurodynamic evidence in patients with tinnitus.

PubMed

Hong, Sung Kwang; Park, Sejik; Ahn, Min-Hee; Min, Byoung-Kyong

2016-12-01

Although a peripheral auditory (bottom-up) deficit is an essential prerequisite for the generation of tinnitus, central cognitive (top-down) impairment has also been shown to be an inherent neuropathological mechanism. Using an auditory oddball paradigm (for top-down analyses) and a passive listening paradigm (for bottom-up analyses) while recording electroencephalograms (EEGs), we investigated whether top-down or bottom-up components were more critical in the neuropathology of tinnitus, independent of peripheral hearing loss. We observed significantly reduced P300 amplitudes (reflecting fundamental cognitive processes such as attention) and evoked theta power (reflecting top-down regulation in memory systems) for target stimuli at the tinnitus frequency of patients with tinnitus but without hearing loss. The contingent negative variation (reflecting top-down expectation of a subsequent event prior to stimulation) and N100 (reflecting auditory bottom-up selective attention) were different between the healthy and patient groups. Interestingly, when tinnitus patients were divided into two subgroups based on their P300 amplitudes, their P170 and N200 components, and annoyance and distress indices to their tinnitus sound were different. EEG theta-band power and its Granger causal neurodynamic results consistently support a double dissociation of these two groups in both top-down and bottom-up tasks. Directed cortical connectivity corroborates that the tinnitus network involves the anterior cingulate and the parahippocampal areas, where higher-order top-down control is generated. Together, our observations provide neurophysiological and neurodynamic evidence revealing a differential engagement of top-down impairment along with deficits in bottom-up processing in patients with tinnitus but without hearing loss. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Detection of CALR and MPL Mutations in Low Allelic Burden JAK2 V617F Essential Thrombocythemia.

PubMed

Usseglio, Fabrice; Beaufils, Nathalie; Calleja, Anne; Raynaud, Sophie; Gabert, Jean

2017-01-01

Myeloproliferative neoplasms are clonal hematopoietic stem cell disorders characterized by aberrant proliferation and an increased tendency toward leukemic transformation. The genes JAK2, MPL, and CALR are frequently altered in these syndromes, and their mutations are often a strong argument for diagnosis. We analyzed the mutational profiles of these three genes in a cohort of 164 suspected myeloproliferative neoplasms. JAK2 V617F mutation was detected by real-time PCR, whereas high-resolution melting analysis followed by Sanger sequencing were used for searching for mutations in JAK2 exon 12, CALR, and MPL. JAK2 V617F mutation was associated with CALR (n = 4) and MPL (n = 4) mutations in 8 of 103 essential thrombocytosis patients. These cases were harboring a JAK2 V617F allelic burden of <4% and a significantly higher platelet count compared with JAK2 V617F (P < 0.001) and CALR (P = 0.001) single-mutation patients. The findings from this study support the possibility of coexisting mutations of the JAK2, CALR, and MPL genes in myeloproliferative neoplasms and suggest that CALR and MPL should be analyzed not only in JAK2-negative patients but also in low V617F mutation patients. Follow-up of these double-mutation cases will be important for determining whether this group of patients presents particular evolution or complications. Copyright © 2017 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Regulation of angiogenesis by phospholipid lysophosphatidic acid.

PubMed

Chen, Yiliang; Ramakrishnan, Devi Prasadh; Ren, Bin

2013-06-01

Lysophosphatidic acid (LPA) as a bioactive phospholipid signaling mediator is emerging as an important regulator of endothelial cell functions and angiogenesis. Many studies have shown that LPA is an active player in regulating the processes of endothelial cell migration, proliferation, and differentiation, all essential in angiogenesis. Through modulating angiogenesis associated gene expression, LPA also promotes pathological angiogenesis. Intriguingly, the angiogenic signaling mechanisms mediated by LPA have been linked to specific G-protein coupled receptors and down stream MAPK including Erk1/2, p38 and JNK, protein kinase D (PKD-1), Rho kinase (ROCK), and the NF-kappa B signaling pathways. LPA regulates angiogenic responses via a complex signaling network, and LPA signaling is integrated and transduced to the nucleus to coordinate the transcription of different angiogenic genes. Investigation of these mechanisms will provide novel and valuable insights into the understanding of endothelial cell biology and angiogenic programs. This knowledge will facilitate designs for better therapies for the ischemic cardiovascular diseases and malignant tumors.

Gene-expression profiles of epithelial cells treated with EMD in vitro: analysis using complementary DNA arrays.

PubMed

Kapferer, I; Schmidt, S; Gstir, R; Durstberger, G; Huber, L A; Vietor, I

2011-02-01

During surgical periodontal treatment, EMD is topically applied in order to facilitate regeneration of the periodontal ligament, acellular cementum and alveolar bone. Suppresion of epithelial down-growth is essential for successful periodontal regeneration; however, the underlying mechanisms of how EMD influences epithelial wound healing are poorly understood. In the present study, the effects of EMD on gene-expression profiling in an epithelial cell line (HSC-2) model were investigated. Gene-expression modifications, determined using a comparative genome-wide expression-profiling strategy, were independently validated by quantitative real-time RT-PCR. Additionally, cell cycle, cell growth and in vitro wound-healing assays were conducted. A set of 43 EMD-regulated genes was defined, which may be responsible for the reduced epithelial down-growth upon EMD application. Gene ontology analysis revealed genes that could be attributed to pathways of locomotion, developmental processes and associated processes such as regulation of cell size and cell growth. Additionally, eight regulated genes have previously been reported to take part in the process of epithelial-to-mesenchymal transition. Several independent experimental assays revealed significant inhibition of cell migration, growth and cell cycle by EMD. The set of EMD-regulated genes identified in this study offers the opportunity to clarify mechanisms underlying the effects of EMD on epithelial cells. Reduced epithelial repopulation of the dental root upon periodontal surgery may be the consequence of reduced migration and cell growth, as well as epithelial-to-mesenchymal transition. © 2010 John Wiley & Sons A/S.

Inverse regulatory coordination of motility and curli-mediated adhesion in Escherichia coli.

PubMed

Pesavento, Christina; Becker, Gisela; Sommerfeldt, Nicole; Possling, Alexandra; Tschowri, Natalia; Mehlis, Anika; Hengge, Regine

2008-09-01

During the transition from post-exponential to stationary phase, Escherichia coli changes from the motile-planktonic to the adhesive-sedentary "lifestyle." We demonstrate this transition to be controlled by mutual inhibition of the FlhDC/motility and sigma(S)/adhesion control cascades at two distinct hierarchical levels. At the top level, motility gene expression and the general stress response are inversely coordinated by sigma(70)/sigma(FliA)/sigma(S) competition for core RNA polymerase and the FlhDC-controlled FliZ protein acting as a sigma(S) inhibitor. At a lower level, the signaling molecule bis-(3'-5')-cyclic-diguanosine monophosphate (c-di-GMP) reduces flagellar activity and stimulates transcription of csgD, which encodes an essential activator of adhesive curli fimbriae expression. This c-di-GMP is antagonistically controlled by sigma(S)-regulated GGDEF proteins (mainly YegE) and YhjH, an EAL protein and c-di-GMP phosphodiesterase under FlhDC/FliA control. The switch from motility-based foraging to the general stress response and curli expression requires sigma(S)-modulated down-regulation of expression of the flagellar regulatory cascade as well as proteolysis of the flagellar master regulator FlhDC. Control of YhjH by FlhDC and of YegE by sigma(S) produces a fine-tuned checkpoint system that "unlocks" curli expression only after down-regulation of flagellar gene expression. In summary, these data reveal the logic and sequence of molecular events underlying the motile-to-adhesive "lifestyle" switch in E. coli.

RNAi-Mediated Reverse Genetic Screen Identified Drosophila Chaperones Regulating Eye and Neuromuscular Junction Morphology.

PubMed

Raut, Sandeep; Mallik, Bhagaban; Parichha, Arpan; Amrutha, Valsakumar; Sahi, Chandan; Kumar, Vimlesh

2017-07-05

Accumulation of toxic proteins in neurons has been linked with the onset of neurodegenerative diseases, which in many cases are characterized by altered neuronal function and synapse loss. Molecular chaperones help protein folding and the resolubilization of unfolded proteins, thereby reducing the protein aggregation stress. While most of the chaperones are expressed in neurons, their functional relevance remains largely unknown. Here, using bioinformatics analysis, we identified 95 Drosophila chaperones and classified them into seven different classes. Ubiquitous actin5C -Gal4-mediated RNAi knockdown revealed that ∼50% of the chaperones are essential in Drosophila Knocking down these genes in eyes revealed that ∼30% of the essential chaperones are crucial for eye development. Using neuron-specific knockdown, immunocytochemistry, and robust behavioral assays, we identified a new set of chaperones that play critical roles in the regulation of Drosophila NMJ structural organization. Together, our data present the first classification and comprehensive analysis of Drosophila chaperones. Our screen identified a new set of chaperones that regulate eye and NMJ morphogenesis. The outcome of the screen reported here provides a useful resource for further elucidating the role of individual chaperones in Drosophila eye morphogenesis and synaptic development. Copyright © 2017 Raut et al.

An intronic microRNA silences genes that are functionally antagonistic to its host gene.

PubMed

Barik, Sailen

2008-09-01

MicroRNAs (miRNAs) are short noncoding RNAs that down-regulate gene expression by silencing specific target mRNAs. While many miRNAs are transcribed from their own genes, nearly half map within introns of 'host' genes, the significance of which remains unclear. We report that transcriptional activation of apoptosis-associated tyrosine kinase (AATK), essential for neuronal differentiation, also generates miR-338 from an AATK gene intron that silences a family of mRNAs whose protein products are negative regulators of neuronal differentiation. We conclude that an intronic miRNA, transcribed together with the host gene mRNA, may serve the interest of its host gene by silencing a cohort of genes that are functionally antagonistic to the host gene itself.

Autophagy up and down by outsmarting the incredible ULK.

PubMed

Nazio, Francesca; Cecconi, Francesco

2017-05-04

Macroautophagy/autophagy initiation is finely regulated by post-translational modifications of key proteins, to comply with the fast kinetics of the cellular response to several stress stimuli. Phosphorylation and ubiquitination play a central role in controlling autophagy by influencing the activity, recruitment and turnover of autophagic components. Recently, we found that, upon autophagy progression, ULK1 kinase is specifically ubiquitinated by the E3 ligase NEDD4L and then degraded via the proteasome. However, during prolonged autophagy, while the ULK1 protein undergoes this inhibition, ULK1 mRNA is actively transcribed, translated and then inhibited again by MTOR-dependent inhibitory phosphorylation. This regulation is essential to promptly restore the ULK1 protein to its original levels to keep autophagy under a safe and physiological threshold.

P44/WDR77 restricts the sensitivity of proliferating cells to TGFβ signaling

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

Yi, Pengfei; Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030; Gao, Shen

2014-07-18

Highlights: • P44/WDR77 causes proliferating cells to become non-responsive to TGFβ signaling. • P44/WDR77 down-regulates TβRII and TβR2 expression. • P44/WDR77 down-regulated TGFβ signaling correlates with lung tumorigenesis. - Abstract: We previously reported that a novel WD-40 domain-containing protein, p44/WDR77, drives quiescent epithelial cells to re-enter the cell cycle and plays an essential role for growth of lung and prostate cancer cells. Transforming growth factor beta (TGFβ) signaling is important in the maintenance of non-transformed cells in the quiescent or slowly cycling stage. However, both non-transformed proliferating cells and human cancer cells are non-responsive to endogenous TGFβ signaling. The mechanismmore » by which proliferating cells become refractory to TGFβ inhibition is not well established. Here, we found that silencing p44/WDR77 increased cellular sensitivity to TGFβ signaling and that this was inversely correlated with decreased cell proliferation. Smad2 or 3 phosphorylation, TGFβ-mediated transcription, and TGFβ2 and TGFβ receptor type II (TβRII) expression were dramatically induced by silencing of p44/WDR77. These data support the hypothesis that p44/WDR77 down-regulates the expression of the TGFβ ligand and its receptor, thereby leading to a cellular non-response to TGFβ signaling. Finally, we found that p44/WDR77 expression was correlated with cell proliferation and decreased TGFβ signaling during lung tumorigenesis. Together, these results suggest that p44/WDR77 expression causes the non-sensitivity of proliferating cells to TGFβ signaling, thereby contributing to cellular proliferation during lung tumorigenesis.« less

Comparative proteomics reveals that YK51, a 4-Hydroxypandurantin-A analogue, downregulates the expression of proteins associated with dengue virus infection.

PubMed

Tan, Wei-Lian; Lee, Yean Kee; Ho, Yen Fong; Yusof, Rohana; Abdul Rahman, Noorsaadah; Karsani, Saiful Anuar

2018-01-01

Dengue is endemic throughout tropical and subtropical regions of the world. Currently, there is no clinically approved therapeutic drug available for this acute viral infection. Although the first dengue vaccine Dengvaxia has been approved for use in certain countries, it is limited to those without a previous dengue infection while the safety and efficacy of the vaccine in those elderly and younger children still need to be identified. Therefore, it is becoming increasingly important to develop therapeutics/drugs to combat dengue virus (DENV) infection. YK51 is a synthetic analogue of 4-Hydroxypandurantin A (a compound found in the crude extract of the rhizomes of Boesenbergia rotunda ) that has been extensively studied by our research group. It has been shown to possess outstanding antiviral activity due to its inhibitory activity against NS2B/NS3 DENV2 protease. However, it is not known how YK51 affects the proteome of DENV infected cells. Therefore, we performed a comparative proteomics analysis to identify changes in protein expression in DENV infected HepG2 cells treated with YK51. Classical two-dimensional gel electrophoresis followed by protein identification using tandem mass spectrometry was employed in this study. Thirty proteins were found to be down-regulated with YK51 treatment. In silico analysis predicted that the down-regulation of eight of these proteins may inhibit viral infection. Our results suggested that apart from inhibiting the NS2B/NS3 DENV2 protease, YK51 may also be causing the down-regulation of a number of proteins that may be responsible in, and/or essential to virus infection. However, functional characterization of these proteins will be necessary before we can conclusively determine their roles in DENV infection.

Comparative proteomics reveals that YK51, a 4-Hydroxypandurantin-A analogue, downregulates the expression of proteins associated with dengue virus infection

PubMed Central

Tan, Wei-Lian; Lee, Yean Kee; Ho, Yen Fong; Yusof, Rohana; Abdul Rahman, Noorsaadah

2018-01-01

Dengue is endemic throughout tropical and subtropical regions of the world. Currently, there is no clinically approved therapeutic drug available for this acute viral infection. Although the first dengue vaccine Dengvaxia has been approved for use in certain countries, it is limited to those without a previous dengue infection while the safety and efficacy of the vaccine in those elderly and younger children still need to be identified. Therefore, it is becoming increasingly important to develop therapeutics/drugs to combat dengue virus (DENV) infection. YK51 is a synthetic analogue of 4-Hydroxypandurantin A (a compound found in the crude extract of the rhizomes of Boesenbergia rotunda) that has been extensively studied by our research group. It has been shown to possess outstanding antiviral activity due to its inhibitory activity against NS2B/NS3 DENV2 protease. However, it is not known how YK51 affects the proteome of DENV infected cells. Therefore, we performed a comparative proteomics analysis to identify changes in protein expression in DENV infected HepG2 cells treated with YK51. Classical two-dimensional gel electrophoresis followed by protein identification using tandem mass spectrometry was employed in this study. Thirty proteins were found to be down-regulated with YK51 treatment. In silico analysis predicted that the down-regulation of eight of these proteins may inhibit viral infection. Our results suggested that apart from inhibiting the NS2B/NS3 DENV2 protease, YK51 may also be causing the down-regulation of a number of proteins that may be responsible in, and/or essential to virus infection. However, functional characterization of these proteins will be necessary before we can conclusively determine their roles in DENV infection. PMID:29404200

Harvest index, a parameter conditioning responsiveness of wheat plants to elevated CO2

PubMed Central

Aranjuelo, Iker; Sanz-Sáez, Álvaro; Jauregui, Iván; Irigoyen, Juan J.; Araus, José L.; Sánchez-Díaz, Manuel; Erice, Gorka

2013-01-01

The expansion of the world’s population requires the development of high production agriculture. For this purpose, it is essential to identify target points conditioning crop responsiveness to predicted [CO2]. The aim of this study was to determine the relevance of ear sink strength in leaf protein and metabolomic profiles and its implications in photosynthetic activity and yield of durum wheat plants exposed to elevated [CO2]. For this purpose, a genotype with high harvest index (HI) (Triticum durum var. Sula) and another with low HI (Triticum durum var. Blanqueta) were exposed to elevated [CO2] (700 µmol mol–1 versus 400 µmol mol–1 CO2) in CO2 greenhouses. The obtained data highlighted that elevated [CO2] only increased plant growth in the genotype with the largest HI; Sula. Gas exchange analyses revealed that although exposure to 700 µmol mol–1 depleted Rubisco content, Sula was capable of increasing the light-saturated rate of CO2 assimilation (Asat) whereas, in Blanqueta, the carbohydrate imbalance induced the down-regulation of Asat. The specific depletion of Rubisco in both genotypes under elevated [CO2], together with the enhancement of other proteins in the Calvin cycle, revealed that there was a redistribution of N from Rubisco towards RuBP regeneration. Moreover, the down-regulation of N, NO3 –, amino acid, and organic acid content, together with the depletion of proteins involved in amino acid synthesis that was detected in Blanqueta grown at 700 µmol mol–1 CO2, revealed that inhibition of N assimilation was involved in the carbohydrate imbalance and consequently with the down-regulation of photosynthesis and growth in these plants. PMID:23564953

BMP4 and LGL1 are Down Regulated in an Ovine Model of Congenital Diaphragmatic Hernia

PubMed Central

Emmerton-Coughlin, Heather M. A.; Martin, K. Kathryn; Chiu, Jacky S. S.; Zhao, Lin; Scott, Leslie A.; Regnault, Timothy R. H.; Bütter, Andreana

2014-01-01

Background/Purpose: The molecular pathophysiology of lung hypoplasia in congenital diaphragmatic hernia (CDH) remains poorly understood. The Wnt signaling pathway and downstream targets, such as bone morphogenetic proteins (BMP) 4 and other factors such as late gestation lung protein 1 (LGL1), are essential to normal lung development. Nitrofen-induced hypoplastic CDH rodent lungs demonstrate down regulation of the Wnt pathway including BMP4 and reduced LGL1 expression. The aim of the current study was to examine the molecular pathophysiology associated with a surgically induced CDH in an ovine model. Methods: Left thoracotomy was performed at 80 days in 14 fetal sheep; CDH was created in seven experimental animals. Lungs were harvested at 136 days (term = 145 days). Lung weight (LW) and mean terminal bronchiole density (MTBD) were measured to determine the degree of pulmonary hypoplasia. Quantitative real time PCR was undertaken to analyze Wnt2, Wnt7b, BMP4, and LGL1 mRNA expression. Results: Total LW was decreased while MTBD was increased in the CDH group (p < 0.05), confirming pulmonary hypoplasia. BMP4 and LGL1 mRNA was significantly reduced in CDH lungs (p < 0.05). Wnt2 mRNA was decreased, although not significantly (p < 0.06). Conclusion: For the first time, down regulation of BMP4 and LGL1 are reported in an ovine CDH model. In contrast to other animal models, these changes are persistent to near term. These findings suggest that mechanical compression from herniated viscera may play a more important role in causing pulmonary hypoplasia in CDH, rather than a primary defect in lung organogenesis. PMID:25593968

Autoregulatory loop of nuclear corepressor 1 expression controls invasion, tumor growth, and metastasis

PubMed Central

Martínez-Iglesias, Olaia A.; Alonso-Merino, Elvira; Gómez-Rey, Sara; Velasco-Martín, Juan Pedro; Martín Orozco, Rosa; Luengo, Enrique; García Martín, Rosa; Ibáñez de Cáceres, Inmaculada; Fernández, Agustín F.; Fraga, Mario F.; González-Peramato, Pilar; Varona, Constantino; Palacios, José; Regadera, Javier; Aranda, Ana

2016-01-01

Nuclear corepressor 1 (NCoR) associates with nuclear receptors and other transcription factors leading to transcriptional repression. We show here that NCoR depletion enhances cancer cell invasion and increases tumor growth and metastatic potential in nude mice. These changes are related to repressed transcription of genes associated with increased metastasis and poor prognosis in patients. Strikingly, transient NCoR silencing leads to heterochromatinization and stable silencing of the NCoR gene, suggesting that NCoR loss can be propagated, contributing to tumor progression even in the absence of NCoR gene mutations. Down-regulation of the thyroid hormone receptor β1 (TRβ) appears to be associated with cancer onset and progression. We found that expression of TRβ increases NCoR levels and that this induction is essential in mediating inhibition of tumor growth and metastasis by this receptor. Moreover, NCoR is down-regulated in human hepatocarcinomas and in the more aggressive breast cancer tumors, and its expression correlates positively with that of TRβ. These data provide a molecular basis for the anticancer actions of this corepressor and identify NCoR as a potential molecular target for development of novel cancer therapies. PMID:26729869

Magnesium supplement promotes sciatic nerve regeneration and down-regulates inflammatory response.

PubMed

Pan, Hung-Chuan; Sheu, Meei-Ling; Su, Hong-Lin; Chen, Ying-Ju; Chen, Chun-Jung; Yang, Dar-Yu; Chiu, Wen-Ta; Cheng, Fu-Chou

2011-06-01

Magnesium (Mg) supplements have been shown to significantly improve functional recovery in various neurological disorders. The essential benefits of Mg supplementation in peripheral nerve disorders have not been elucidated yet. The effect and mechanism of Mg supplementation on a sciatic nerve crush injury model was investigated. Sciatic nerve injury was induced in mice by crushing the left sciatic nerve. Mice were randomly divided into three groups with low-, basal- or high-Mg diets (corresponding to 10, 100 or 200% Mg of the basal diet). Neurobehavioral, electrophysiological and regeneration marker studies were conducted to explore nerve regeneration. First, a high Mg diet significantly increased plasma and nerve tissue Mg concentrations. In addition, Mg supplementation improved neurobehavioral, electrophysiological functions, enhanced regeneration marker, and reduced deposits of inflammatory cells as well as expression of inflammatory cytokines. Furthermore, reduced Schwann cell apoptosis was in line with the significant expression of bcl-2, bcl-X(L) and down-regulated expression of active caspase-3 and cytochrome C. In summary, improved neurological function recovery and enhanced nerve regeneration were found in mice with a sciatic nerve injury that were fed a high- Mg diet, and Schwann cells may have been rescued from apoptosis by the suppression of inflammatory responses.

The effect of arousal on regulation of negative emotions using cognitive reappraisal: An ERP study.

PubMed

Langeslag, Sandra J E; Surti, Kruti

2017-08-01

Because the effectiveness of the emotion regulation strategy cognitive reappraisal may vary with emotion intensity, we investigated how stimulus arousal affects reappraisal success. Participants up- and down-regulated emotional responses using cognitive reappraisal to low and high arousing unpleasant pictures while the electroencephalogram (EEG) was recorded. Up-regulation resulted in more negative self-reported valence, while down-regulation resulted in less negative self-reported valence regardless of stimulus arousal, suggesting that subjective reappraisal success does not vary with emotional intensity. Participants felt that down-regulation of emotional responses to low arousing unpleasant pictures was easiest, which is in line with previous findings that participants showed a greater preference for reappraisal in low than high arousing situations. The late positive potential (LPP) amplitude was enhanced by down-regulation of high arousing unpleasant pictures. Even though this effect was unexpected and is opposite to the typical effect of down-regulation on the LPP, it is in line with several previous studies. Potential explanations for LPP regulation effects in the unexpected direction, such as strategy selection and task design, are evaluated. Suggestions and recommendations for future research are discussed, including using trial-by-trial manipulation of regulation instructions and studying the effect of stimulus arousal on up- and down-regulation of positive emotions. Copyright © 2017 Elsevier B.V. All rights reserved.

An MPL W515L mutation in refractory anemia with ringed sideroblasts associated with marked thrombocytosis: A case report.

PubMed

Hao, Lin; Sen, Sandeep; Sugumar, Dhivya

2015-02-01

The current study presents the case of a 63-year-old patient exhibiting refractory anemia with ringed sideroblasts associated with marked thrombocytosis (RARS-T), who was positive for the MPL W515L mutation, but negative for the JAK2 V617F mutation. Following diagnosis, the patient remained asymptomatic for over three years, however, in August 2012, the patient relapsed and was administered with supportive treatment in the form of subcutaneous darbepoetin α at a dose of 300 μg/week, which resulted in an increased hemoglobin concentration, allowing the patient to remain transfusion-independent. The MPL W515L mutation has been reported in two previous cases of myelodysplastic/myeloproliferative neoplasms (MDS/MPN) with ringed sideroblasts, however, to the best of our knowledge, the current report is the first to present a case of RARS-T with an MPL W515L mutation. A clinical trial designed to evaluate the efficacy of a targeted agent against the JAK2 V617F mutation is currently ongoing, with the aim of providing a novel therapeutic strategy for treating MDS/MPN patients. As MPL is located upstream of the JAK-STAT signaling pathway, it is a possible therapeutic target in MDS/MPN patients positive for an MPL W515L mutation, but negative for a JAK2 V617F mutation.

JAK2V617F-mutant megakaryocytes contribute to hematopoietic stem/progenitor cell expansion in a model of murine myeloproliferation

PubMed Central

Zhan, H; Ma, Y; Lin, CHS; Kaushansky, K

2016-01-01

The myeloproliferative neoplasms (MPNs) are characterized by hematopoietic stem/progenitor cell (HSPC) expansion and overproduction of mature blood cells. The JAK2V617F mutation is present in hematopoietic cells in a majority of patients with MPNs, but the mechanism(s) responsible for MPN stem cell expansion remain incomplete. One hallmark feature of the marrow in patients with MPNs is megakaryocyte (MK) hyperplasia. We report here that mice bearing a human JAK2V617F gene restricted exclusively to the MK lineage develop many of the features of a MPN. Specifically, these mice exhibit thrombocytosis, splenomegaly, increased numbers of marrow and splenic hematopoietic progenitors and a substantial expansion of HSPCs. In addition, wild-type mice transplanted with cells from JAK2V617F-bearing MK marrow develop a myeloproliferative syndrome with thrombocytosis and erythrocytosis as well as pan-hematopoietic progenitor and stem cell expansion. As marrow histology in this murine model of myeloproliferation reveals a preferentially perivascular localization of JAK2V617F-mutant MKs and an increased marrow sinusoid vascular density, it adds to accumulating data that MKs are an important component of the marrow HSPC niche, and that MK expansion might indirectly contribute to the critical role of the thrombopoietin/c-Mpl signaling pathway in HSPC maintenance and expansion. PMID:27133820

The significance of translation regulation in the stress response

PubMed Central

2013-01-01

Background The stress response in bacteria involves the multistage control of gene expression but is not entirely understood. To identify the translational response of bacteria in stress conditions and assess its contribution to the regulation of gene expression, the translational states of all mRNAs were compared under optimal growth condition and during nutrient (isoleucine) starvation. Results A genome-scale study of the translational response to nutritional limitation was performed in the model bacterium Lactococcus lactis. Two measures were used to assess the translational status of each individual mRNA: the fraction engaged in translation (ribosome occupancy) and ribosome density (number of ribosomes per 100 nucleotides). Under isoleucine starvation, half of the mRNAs considered were translationally down-regulated mainly due to decreased ribosome density. This pattern concerned genes involved in growth-related functions such as translation, transcription, and the metabolism of fatty acids, phospholipids and bases, contributing to the slowdown of growth. Only 4% of the mRNAs were translationally up-regulated, mostly related to prophagic expression in response to stress. The remaining genes exhibited antagonistic regulations of the two markers of translation. Ribosome occupancy increased significantly for all the genes involved in the biosynthesis of isoleucine, although their ribosome density had decreased. The results revealed complex translational regulation of this pathway, essential to cope with isoleucine starvation. To elucidate the regulation of global gene expression more generally, translational regulation was compared to transcriptional regulation under isoleucine starvation and to other post-transcriptional regulations related to mRNA degradation and mRNA dilution by growth. Translational regulation appeared to accentuate the effects of transcriptional changes for down-regulated growth-related functions under isoleucine starvation although mRNA stabilization and lower dilution by growth counterbalanced this effect. Conclusions We show that the contribution of translational regulation to the control of gene expression is significant in the stress response. Post-transcriptional regulation is complex and not systematically co-directional with transcription regulation. Post-transcriptional regulation is important to the understanding of gene expression control. PMID:23985063

Identification of a cis-Regulatory Element Involved in Phytochrome Down-Regulated Expression of the Pea Small GTPase Gene pra21

PubMed Central

Inaba, Takehito; Nagano, Yukio; Sakakibara, Toshihiro; Sasaki, Yukiko

1999-01-01

The pra2 gene encodes a pea (Pisum sativum) small GTPase belonging to the YPT/rab family, and its expression is down-regulated by light, mediated by phytochrome. We have isolated and characterized a genomic clone of this gene and constructed a fusion DNA of its 5′-upstream region in front of the gene for firefly luciferase. Using this construct in a transient assay, we determined a pra2 cis-regulatory region sufficient to direct the light down-regulation of the luciferase reporter gene. Both 5′- and internal deletion analyses revealed that the 93-bp sequence between −734 and −642 from the transcriptional start site was important for phytochrome down-regulation. Gain-of-function analysis showed that this 93-bp region could confer light down-regulation when fused to the cauliflower mosaic virus 35S promoter. Furthermore, linker-scanning analysis showed that a 12-bp sequence within the 93-bp region mediated phytochrome down-regulation. Gel-retardation analysis showed the presence of a nuclear factor that was specifically bound to the 12-bp sequence in vitro. These results indicate that this element is a cis-regulatory element involved in phytochrome down-regulated expression. PMID:10364400

Vegan proteins may reduce risk of cancer, obesity, and cardiovascular disease by promoting increased glucagon activity.

PubMed

McCarty, M F

1999-12-01

Amino acids modulate the secretion of both insulin and glucagon; the composition of dietary protein therefore has the potential to influence the balance of glucagon and insulin activity. Soy protein, as well as many other vegan proteins, are higher in non-essential amino acids than most animal-derived food proteins, and as a result should preferentially favor glucagon production. Acting on hepatocytes, glucagon promotes (and insulin inhibits) cAMP-dependent mechanisms that down-regulate lipogenic enzymes and cholesterol synthesis, while up-regulating hepatic LDL receptors and production of the IGF-I antagonist IGFBP-1. The insulin-sensitizing properties of many vegan diets--high in fiber, low in saturated fat--should amplify these effects by down-regulating insulin secretion. Additionally, the relatively low essential amino acid content of some vegan diets may decrease hepatic IGF-I synthesis. Thus, diets featuring vegan proteins can be expected to lower elevated serum lipid levels, promote weight loss, and decrease circulating IGF-I activity. The latter effect should impede cancer induction (as is seen in animal studies with soy protein), lessen neutrophil-mediated inflammatory damage, and slow growth and maturation in children. In fact, vegans tend to have low serum lipids, lean physiques, shorter stature, later puberty, and decreased risk for certain prominent 'Western' cancers; a vegan diet has documented clinical efficacy in rheumatoid arthritis. Low-fat vegan diets may be especially protective in regard to cancers linked to insulin resistance--namely, breast and colon cancer--as well as prostate cancer; conversely, the high IGF-I activity associated with heavy ingestion of animal products may be largely responsible for the epidemic of 'Western' cancers in wealthy societies. Increased phytochemical intake is also likely to contribute to the reduction of cancer risk in vegans. Regression of coronary stenoses has been documented during low-fat vegan diets coupled with exercise training; such regimens also tend to markedly improve diabetic control and lower elevated blood pressure. Risk of many other degenerative disorders may be decreased in vegans, although reduced growth factor activity may be responsible for an increased risk of hemorrhagic stroke. By altering the glucagon/insulin balance, it is conceivable that supplemental intakes of key non-essential amino acids could enable omnivores to enjoy some of the health advantages of a vegan diet. An unnecessarily high intake of essential amino acids--either in the absolute sense or relative to total dietary protein--may prove to be as grave a risk factor for 'Western' degenerative diseases as is excessive fat intake.

MicroRNA-218 promotes high glucose-induced apoptosis in podocytes by targeting heme oxygenase-1.

PubMed

Yang, Haibo; Wang, Qingjun; Li, Sutong

2016-03-18

Emerging evidence has demonstrated that microRNAs (miRNAs) play a mediatory role in the pathogenesis of diabetic nephropathy. In this study, we found that miR-218 was upregulated in high glucose (HG) treated podocytes, which are essential components of the glomerular filtration barrier and a major prognostic determinant in diabetic nephropathy. Additionally, up-regulation of miR-218 was accompanied by an increased rate of podocyte death and down-regulation in the level of nephrin, a key marker of podocytes. However, inhibition of miR-218 exerted the opposite effect. In addition, the dual-luciferase reporter assay showed that miR-218 directly targeted the 3'-untranslated region of heme oxygenase-1 (HO-1), and further study confirmed an increase of HO-1 in HG-treated podocytes transfected with anti-miR-218. Knockdown of HO-1 blocked the anti-apoptotic effect of anti-miR-218. Furthermore, inhibition of miR-218 was associated with decreased expression of the known pro-apoptotic molecule p38-mitogen-activated protein kinase (p38-MAPK) activation. Following preconditioning with SB203580, an inhibitor of p38-MAPK, the stimulatory effect of HG on podocyte apoptosis was strikingly ameliorated. These findings suggested that miR-218 accelerated HG-induced podocyte apoptosis through directly down-regulating HO-1 and facilitating p38-MAPK activation. Copyright © 2016 Elsevier Inc. All rights reserved.

An ethanolic extract of Artemisia dracunculus L. regulates gene expression of ubiquitin-proteasome system enzymes in skeletal muscle: potential role in the treatment of sarcopenic obesity.

PubMed

Kirk-Ballard, Heather; Kilroy, Gail; Day, Britton C; Wang, Zhong Q; Ribnicky, David M; Cefalu, William T; Floyd, Z Elizabeth

2014-01-01

Obesity is linked to insulin resistance, a primary component of metabolic syndrome and type 2 diabetes. The problem of obesity-related insulin resistance is compounded when age-related skeletal muscle loss, called sarcopenia, occurs with obesity. Skeletal muscle loss results from elevated levels of protein degradation and prevention of obesity-related sarcopenic muscle loss will depend on strategies that target pathways involved in protein degradation. An extract from Artemisia dracunculus, termed PMI 5011, improves insulin signaling and increases skeletal muscle myofiber size in a rodent model of obesity-related insulin resistance. The aim of this study was to examine the effect of PMI 5011 on the ubiquitin-proteasome system, a central regulator of muscle protein degradation. Gastrocnemius and vastus lateralis skeletal muscle was obtained from KK-A(y) obese diabetic mice fed a control or 1% (w/w) PMI 5011-supplemented diet. Regulation of genes encoding enzymes of the ubiquitin-proteasome system was determined using real-time quantitative reverse transcriptase polymerase chain reaction. Although MuRF-1 ubiquitin ligase gene expression is consistently down-regulated in skeletal muscle, atrogin-1, Fbxo40, and Traf6 expression is differentially regulated by PMI 5011. Genes encoding other enzymes of the ubiquitin-proteasome system ranging from ubiquitin to ubiquitin-specific proteases are also regulated by PMI 5011. Additionally, expression of the gene encoding the microtubule-associated protein-1 light chain 3 (LC3), a ubiquitin-like protein pivotal to autophagy-mediated protein degradation, is down-regulated by PMI 5011 in the vastus lateralis. PMI 5011 alters the gene expression of ubiquitin-proteasome system enzymes that are essential regulators of skeletal muscle mass. This suggests that PMI 5011 has therapeutic potential in the treatment of obesity-linked sarcopenia by regulating ubiquitin-proteasome-mediated protein degradation. Copyright © 2014 Elsevier Inc. All rights reserved.

SGK3 sustains ERα signaling and drives acquired aromatase inhibitor resistance through maintaining endoplasmic reticulum homeostasis.

PubMed

Wang, Yuanzhong; Zhou, Dujin; Phung, Sheryl; Warden, Charles; Rashid, Rumana; Chan, Nymph; Chen, Shiuan

2017-02-21

Many estrogen receptor alpha (ERα)-positive breast cancers initially respond to aromatase inhibitors (AIs), but eventually acquire resistance. Here, we report that serum- and glucocorticoid-inducible kinase 3 (SGK3), a kinase transcriptionally regulated by ERα in breast cancer, sustains ERα signaling and drives acquired AI resistance. SGK3 is up-regulated and essential for endoplasmic reticulum (EnR) homeostasis through preserving sarcoplasmic/EnR calcium ATPase 2b (SERCA2b) function in AI-resistant cells. We have further found that EnR stress response down-regulates ERα expression through the protein kinase RNA-like EnR kinase (PERK) arm, and SGK3 retains ERα expression and signaling by preventing excessive EnR stress. Our study reveals regulation of ERα expression mediated by the EnR stress response and the feed-forward regulation between SGK3 and ERα in breast cancer. Given SGK3 inhibition reduces AI-resistant cell survival by eliciting excessive EnR stress and also depletes ERα expression/function, we propose SGK3 inhibition as a potential effective treatment of acquired AI-resistant breast cancer.

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

Peek, Gregory W.; Tollefsbol, Trygve O., E-mail: trygve@uab.edu; Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL

Human telomerase reverse transcriptase (hTERT) is the catalytic and limiting component of telomerase and also a transcription factor. It is critical to the integrity of the ends of linear chromosomes and to the regulation, extent and rate of cell cycle progression in multicellular eukaryotes. The level of hTERT expression is essential to a wide range of bodily functions and to avoidance of disease conditions, such as cancer, that are mediated in part by aberrant level and regulation of cell cycle proliferation. Value of a gene in regulation depends on its ability to both receive input from multiple sources and transmitmore » signals to multiple effectors. The expression of hTERT and the progression of the cell cycle have been shown to be regulated by an extensive network of gene products and signaling pathways, including the PI3K/Akt and TGF-β pathways. The PI3K inhibitor PX-866 and the competitive estrogen receptor ligand raloxifene have been shown to modify progression of those pathways and, in combination, to decrease proliferation of estrogen receptor positive (ER+) MCF-7 breast cancer cells. We found that combinations of modulators of those pathways decreased not only hTERT transcription but also transcription of additional essential cell cycle regulators such as Cyclin D1. By evaluating known expression profile signatures for TGF-β pathway diversions, we confirmed additional genes such as heparin-binding epidermal growth factor-like growth factor (HB EGF) by which those pathways and their perturbations may also modify cell cycle progression. - Highlights: • PX-866 and raloxifene affect the PI3K/Akt and TGF-β pathways. • PX-866 and raloxifene down-regulate genes up-regulated in cancer. • PX-866 and raloxifene decrease transcription of hTERT and Cyclin D1. • Pathological transcription signatures can identify new defense mechanisms.« less

Temperature control of fimbriation circuit switch in uropathogenic Escherichia coli: quantitative analysis via automated model abstraction.

PubMed

Kuwahara, Hiroyuki; Myers, Chris J; Samoilov, Michael S

2010-03-26

Uropathogenic Escherichia coli (UPEC) represent the predominant cause of urinary tract infections (UTIs). A key UPEC molecular virulence mechanism is type 1 fimbriae, whose expression is controlled by the orientation of an invertible chromosomal DNA element-the fim switch. Temperature has been shown to act as a major regulator of fim switching behavior and is overall an important indicator as well as functional feature of many urologic diseases, including UPEC host-pathogen interaction dynamics. Given this panoptic physiological role of temperature during UTI progression and notable empirical challenges to its direct in vivo studies, in silico modeling of corresponding biochemical and biophysical mechanisms essential to UPEC pathogenicity may significantly aid our understanding of the underlying disease processes. However, rigorous computational analysis of biological systems, such as fim switch temperature control circuit, has hereto presented a notoriously demanding problem due to both the substantial complexity of the gene regulatory networks involved as well as their often characteristically discrete and stochastic dynamics. To address these issues, we have developed an approach that enables automated multiscale abstraction of biological system descriptions based on reaction kinetics. Implemented as a computational tool, this method has allowed us to efficiently analyze the modular organization and behavior of the E. coli fimbriation switch circuit at different temperature settings, thus facilitating new insights into this mode of UPEC molecular virulence regulation. In particular, our results suggest that, with respect to its role in shutting down fimbriae expression, the primary function of FimB recombinase may be to effect a controlled down-regulation (rather than increase) of the ON-to-OFF fim switching rate via temperature-dependent suppression of competing dynamics mediated by recombinase FimE. Our computational analysis further implies that this down-regulation mechanism could be particularly significant inside the host environment, thus potentially contributing further understanding toward the development of novel therapeutic approaches to UPEC-caused UTIs.

Enhancement of the Effect of Methyl Pyropheophorbide-a-Mediated Photodynamic Therapy was Achieved by Increasing ROS through Inhibition of Nrf2-HO-1 or Nrf2-ABCG2 Signaling.

PubMed

Tian, Si; Yong, Min; Zhu, Jiang; Zhang, Li; Pan, Li; Chen, Qing; Li, Kai-Ting; Kong, Yu-Han; Jiang, Yuan; Yu, Ting-He; Yu, Le-Hua; Bai, Ding-Qun

2017-01-01

Emerging evidence indicates that the transcription factor nuclear factor-E2-related factor 2 (Nrf2) plays an essential role in cellular defense against oxidative stress; its activation has been related to cytoprotection. Here, we investigated the role of Nrf2 in improving the efficacy of methyl pyropheophorbide-amediated photodynamic therapy (Mppa-PDT) via the downregulation of Nrf2. Human ovarian cancer A2780 cells and SKOV3 cells were treated with Mppa-PDT and siRNA transfection was performed to inhibit Nrf2. After treated with siRNA and Mppa-PDT, the cell viability was examined with CCK-8 assay; cell apoptosis was detected tested by flow cytometry with Annexin V-FITC/PI; the celluar reactive oxygen species (ROS) and mitochondrial membrane potential were measured with DCFHDA and JC-1 staining; expression of protein was assessed by western blot analysis. We found that Nrf2 translocated from the cytoplasm to the nucleus in vitro and in vivo, and the expression of Nrf2 and P-Nrf2 increased through a possible mechanism regulated by mitogen-activated protein kinase (MAPK) after Mppa-PDT treatment. Furthermore, cytotoxicity and apoptosis induced by Mppa-PDT increased after Nrf2down-regulation. Nrf2 down -regulation increased reactive oxygen species (ROS) levels by attenuating antioxidants or pumping Mppa out of cells,which resulted from the inhibition of Nrf2-HO-1 or Nrf2- ABCG2 signaling. In addition, SKOV3 cells exhibited increased resistance to Mppa-PDT, and the expression levels of P-Nrf2 and ABCG2 were higher in SKOV3 cells than in A2780 cells, suggesting that Nrf2-ABCG2 signaling might be involved in the intrinsic resistanceto Mppa-PDT. These results provided evidence that Nrf2 down-regulation can enhance the effect of Mppa-PDT. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Estrogen-Induced Maldevelopment of the Penis Involves Down-Regulation of Myosin Heavy Chain 11 (MYH11) Expression, a Biomarker for Smooth Muscle Cell Differentiation1

PubMed Central

Okumu, L.A.; Bruinton, Sequoia; Braden, Tim D.; Simon, Liz; Goyal, Hari O.

2012-01-01

ABSTRACT Cavernous smooth muscle cells are essential components in penile erection. In this study, we investigated effects of estrogen exposure on biomarkers for smooth muscle cell differentiation in the penis. Neonatal rats received diethylstilbestrol (DES), with or without the estrogen receptor (ESR) antagonist ICI 182,780 (ICI) or the androgen receptor (AR) agonist dihydrotestosterone (DHT), from Postnatal Days 1 to 6. Tissues were collected at 7, 10, or 21 days of age. The smooth muscle cell biomarker MYH11 was studied in depth because microarray data showed it was significantly down-regulated, along with other biomarkers, in DES treatment. Quantitative real time-PCR and Western blot analyses showed 50%–80% reduction (P ≤ 0.05) in Myh11 expression in DES-treated rats compared to that in controls; and ICI and DHT coadministration mitigated the decrease. Temporally, from 7 to 21 days of age, Myh11 expression was onefold increased (P ≥ 0.05) in DES-treated rats versus threefold increased (P ≤ 0.001) in controls, implying the long-lasting inhibitory effect of DES on smooth muscle cell differentiation. Immunohistochemical localization of smooth muscle alpha actin, another biomarker for smooth muscle cell differentiation, showed fewer cavernous smooth muscle cells in DES-treated animals than in controls. Additionally, DES treatment significantly up-regulated Esr1 mRNA expression and suppressed the neonatal testosterone surge by 90%, which was mitigated by ICI coadministration but not by DHT coadministration. Collectively, results provided evidence that DES treatment in neonatal rats inhibited cavernous smooth muscle cell differentiation, as shown by down-regulation of MYH11 expression at the mRNA and protein levels and by reduced immunohistochemical staining of smooth muscle alpha actin. Both the ESR and the AR pathways probably mediate this effect. PMID:22976277

The KRAS Promoter Responds to Myc-associated Zinc Finger and Poly(ADP-ribose) Polymerase 1 Proteins, Which Recognize a Critical Quadruplex-forming GA-element*

PubMed Central

Cogoi, Susanna; Paramasivam, Manikandan; Membrino, Alexandro; Yokoyama, Kazunari K.; Xodo, Luigi E.

2010-01-01

The murine KRAS promoter contains a G-rich nuclease hypersensitive element (GA-element) upstream of the transcription start site that is essential for transcription. Pulldown and chromatin immunoprecipitation assays demonstrate that this GA-element is bound by the Myc-associated zinc finger (MAZ) and poly(ADP-ribose) polymerase 1 (PARP-1) proteins. These proteins are crucial for transcription, because when they are knocked down by short hairpin RNA, transcription is down-regulated. This is also the case when the poly(ADP-ribosyl)ation activity of PARP-1 is inhibited by 3,4-dihydro-5-[4-(1-piperidinyl) butoxyl]-1(2H) isoquinolinone. We found that MAZ specifically binds to the duplex and quadruplex conformations of the GA-element, whereas PARP-1 shows specificity only for the G-quadruplex. On the basis of fluorescence resonance energy transfer melting and polymerase stop assays we saw that MAZ stabilizes the KRAS quadruplex. When the capacity of folding in the GA-element is abrogated by specific G → T or G → A point mutations, KRAS transcription is down-regulated. Conversely, guanidine-modified phthalocyanines, which specifically interact with and stabilize the KRAS G-quadruplex, push the promoter activity up to more than double. Collectively, our data support a transcription mechanism for murine KRAS that involves MAZ, PARP-1 and duplex-quadruplex conformational changes in the promoter GA-element. PMID:20457603

Transcriptional and physiological analyses of Fe deficiency response in maize reveal the presence of Strategy I components and Fe/P interactions.

PubMed

Zanin, Laura; Venuti, Silvia; Zamboni, Anita; Varanini, Zeno; Tomasi, Nicola; Pinton, Roberto

2017-02-13

Under limited iron (Fe) availability maize, a Strategy II plant, improves Fe acquisition through the release of phytosiderophores (PS) into the rhizosphere and the subsequent uptake of Fe-PS complexes into root cells. Occurrence of Strategy-I-like components and interactions with phosphorous (P) nutrition has been hypothesized based on molecular and physiological studies in grasses. In this report transcriptomic analysis (NimbleGen microarray) of Fe deficiency response revealed that maize roots modulated the expression levels of 724 genes (508 up- and 216 down-regulated, respectively). As expected, roots of Fe-deficient maize plants overexpressed genes involved in the synthesis and release of 2'-deoxymugineic acid (the main PS released by maize roots). A strong modulation of genes involved in regulatory aspects, Fe translocation, root morphological modification, primary metabolic pathways and hormonal metabolism was induced by the nutritional stress. Genes encoding transporters for Fe 2+ (ZmNRAMP1) and P (ZmPHT1;7 and ZmPHO1) were also up-regulated under Fe deficiency. Fe-deficient maize plants accumulated higher amounts of P than the Fe-sufficient ones, both in roots and shoots. The supply of 1 μM 59 Fe, as soluble (Fe-Citrate and Fe-PS) or sparingly soluble (Ferrihydrite) sources to deficient plants, caused a rapid down-regulation of genes coding for PS and Fe(III)-PS transport, as well as of ZmNRAMP1 and ZmPHT1;7. Levels of 32 P absorption essentially followed the rates of 59 Fe uptake in Fe-deficient plants during Fe resupply, suggesting that P accumulation might be regulated by Fe uptake in maize plants. The transcriptional response to Fe-deficiency in maize roots confirmed the modulation of known genes involved in the Strategy II and revealed the presence of Strategy I components usually described in dicots. Moreover, data here presented provide evidence of a close relationship between two essential nutrients for plants, Fe and P, and highlight a key role played by Fe and P transporters to preserve the homeostasis of these two nutrients in maize plants.

MicroRNA-137 Negatively Regulates H2O2-Induced Cardiomyocyte Apoptosis Through CDC42

PubMed Central

Wang, Junnan; Xu, Rihao; Wu, Junduo; Li, Zhibo

2015-01-01

Background Oxidative stress, inducing cardiomyocyte apoptosis or myocardial ischemia, is the major denominator of many cardiac diseases. In this study, we intended to explore the regulatory function of microRNA-137 (miR-137) in oxidative stress-induced cardiomyocyte apoptosis. Material/Methods Cardiomyocytes were extracted from newborn C57BL/6 mice and cultured in vitro. Apoptosis was induced by H2O2, and evaluated by TUNEL assay. The effect of cardiomyocyte apoptosis on gene expression of miR-137 was evaluated by qRT-PCR. Lentivirus was used to stably down-regulate miR-137, and the subsequent effects of miR-137 down-regulation on cardiomyocyte apoptosis, its targeted gene CDC42, and caspase pathway were evaluated by TUNEL assay, dual-luciferase reporter assay, and Western blot assay, respectively. Finally, CDC42 was down-regulated by siRNA and its effect on miR-137-mediated cardiomyocyte apoptosis protection was examined. Results H2O2 induced significant apoptosis and up-regulated miR-137 in cardiomyocytes, whereas lentivirus-mediated miR-137 down-regulation protected against apoptosis. CDC42 was the direct target gene of miR-137 and proteins of CDC42, caspase-3, and caspase-9 were all regulated by miR-137 down-regulation in cardiomyocyte apoptosis. SiRNA-mediated CDC42 down-regulation reversed the protection of miR-137 down-regulation against cardiomyocyte apoptosis. Conclusions Our work demonstrated miR-137 and CDC42 are critical regulators in cardiomyocyte apoptosis. It may help to identify the molecular targets to prevent myocardial injury in human patients. PMID:26566162

[Phase II study of YNK01 (1-beta-D-arabinofuranosylcytosine-5'-stearylphosphate) on hematological malignancies].

PubMed

Tatsumi, N; Yamada, K; Ohshima, T; Nakamura, T; Ohno, R; Masaoka, T; Kimura, I; Kimura, K

1990-12-01

Phase II study of YNK01 (1-beta-D-arabinofuranosylcytosine-5'-stearylphosphate), a derivative of cytosine arabinoside, on hematological malignancies was conducted by multi-institutional cooperative group. YNK01 was administered orally at dose of 100-300 mg/body/day for more than 2 weeks. The number of registered and evaluated patients were 211 and 156, respectively. Of 23 patients with acute myelogeneous leukemia (AML), 2 complete response (CR), one partial response (PR) were observed (CR + PR: 13.0%). Hypoplastic leukemia (1/4: 25%), acute unclassified leukemia (1/1: 100%). Of 45 patients with MDS, 2CRs, 6 good response (GR) and 5PRs were observed (CR + PR: 28.9%). AML developing after a prior history of MDS (5/17: 29.4%), CML-BC (2/9: 22.2%). Of 19 patients with CML, 9 achieved CR, 3 achieved PR (63.2%). Of 11 patients with polycythemia vera, 4 achieved CR, 5 achieved PR (81.8%). Of 6 patients with essential thrombocytosis, 2 achieved CR, one achieved PR (50%). The major adverse effects included gastrointestinal toxicities such as nausea, vomiting, anorexia, diarrhea, and elevation of GOT and GPT which were tolerable and reversible. This study indicates that YNK01 is a useful agent against acute leukemia and MDS, especially RAEB, RAEB in T, CMMoL.

Radiophosphorus (/sup 32/P) treatment of bone marrow disorders in dogs: 11 cases (1970-1987)

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

Smith, M.; Turrel, J.M.

1989-01-01

Between March 1970 and February 1987, radiophosphorus (/sup 32/P) was used to treat bone marrow disorders in 6 dogs; 4 had polycythemia vera and 2 had essential thrombocythemia. Activities of /sup 32/P given initially ranged from 2.4 to 3.3 mCi/m2. Four dogs responded well to /sup 32/P treatment, with gradual resolution of high RBC or platelet counts. Two of these dogs died of intercurrent disease unrelated to their bone marrow disorder, before blood counts could be stabilized. Two dogs did not respond to the initial /sup 32/P treatment nor to additional treatments with /sup 32/P, and had clinical signs andmore » blood counts stabilized by use of phlebotomy or chemotherapeutic agents. We reviewed and analyzed 5 other cases of bone marrow disorders in dogs treated with /sup 32/P and included the findings from their records with the records of our 6 dogs in this retrospective analysis. Of the 8 dogs with polycythemia vera treated with /sup 32/P, 5 were given a single treatment that controlled clinical signs and blood counts for the remainder of the follow-up period. Of the 3 dogs treated for thrombocytosis with /sup 32/P, 2 had blood counts that responded to a single treatment.« less

Use of CBL exon 8 and 9 mutations in diagnosis of myeloproliferative neoplasms and myelodysplastic/myeloproliferative disorders: an analysis of 636 cases

PubMed Central

Schnittger, Susanne; Bacher, Ulrike; Alpermann, Tamara; Reiter, Andreas; Ulke, Madlen; Dicker, Frank; Eder, Christiane; Kohlmann, Alexander; Grossmann, Vera; Kowarsch, Andreas; Kern, Wolfgang; Haferlach, Claudia; Haferlach, Torsten

2012-01-01

We analyzed 636 patients with diverse myeloproliferative neoplasms or myelodysplastic/myeloproliferative neoplasms for mutations of the Casitas B-cell lymphoma gene (CBLmut) in exons 8 and 9 and performed correlations to other genetic alterations. CBLmut were detected in 63 of 636 (9.9%) of these selected patients. CBLmut were more frequent in myelodysplastic/myeloproliferative neoplasms than myeloproliferative neoplasms (51 of 328, 15.5% vs. 12 of 291, 4.1%; P<0.001). Frequency was 48 of 278 (17.3%) in chronic myelomonocytic leukemia and 3 of 33 (9.1%) in unclassifiable myelodysplastic/myeloproliferative neoplasms. CBLmut was not detected in polycythemia vera, primary myelofibrosis, essential thrombocythemia, or refractory anemia with ring sideroblasts and marked thrombocytosis. CBLmut were underrepresented in JAK2V617F mutated as compared to JAK2V617wt cases (P<0.001), and mutually exclusive of JAK2exon12mut and MPLW515mut. CBLmut were associated with monosomy 7 (P=0.008) and TET2mut (P=0.003). In chronic myelomonocytic leukemia, CBLmut had no significant impact on survival outcomes. Therefore, CBLmut are frequent in chronic myelomonocytic leukemia, absent in classical myeloproliferative neoplasms, and are only exceptionally found in coincidence with JAK-STAT pathway activating mutations. PMID:22733026

A lower intensity of treatment may underlie the increased risk of thrombosis in young patients with masked polycythaemia vera.

PubMed

Lussana, Federico; Carobbio, Alessandra; Randi, Maria L; Elena, Chiara; Rumi, Elisa; Finazzi, Guido; Bertozzi, Irene; Pieri, Lisa; Ruggeri, Marco; Palandri, Francesca; Polverelli, Nicola; Elli, Elena; Tieghi, Alessia; Iurlo, Alessandra; Ruella, Marco; Cazzola, Mario; Rambaldi, Alessandro; Vannucchi, Alessandro M; Barbui, Tiziano

2014-11-01

In patients who do not meet the World Health Organization (WHO) criteria for overt polycythaemia vera (PV), a diagnosis of masked PV (mPV) can be determined. A fraction of mPV patients may display thrombocytosis, thus mimicking essential thrombocythaemia (ET). No previous studies have examined clinical outcomes of mPV among young JAK2-mutated patients. We analysed a retrospective cohort of 538 JAK2-mutated patients younger than 40 years, after a re-assessment of the diagnosis according to the haemoglobin threshold for mPV. In this cohort of patients, 97 (18%) met the WHO criteria for PV, 66 patients (12%) were classified as mPV and 375 (70%) as JAK2-mutated ET. Surprisingly, a significant difference in the incidence of thrombosis was found when comparing mPV versus overt PV patients (P = 0·04). In multivariate analysis, the only factor accounting for the difference in the risk of thrombosis was the less frequent use of phlebotomies and cytoreduction in mPV patients compared to those with overt PV. Thus, we emphasize the need for the identification of mPV in young JAK2-mutated patients in order to optimize their treatments. © 2014 John Wiley & Sons Ltd.

Kif4 Is Essential for Mouse Oocyte Meiosis.

PubMed

Camlin, Nicole J; McLaughlin, Eileen A; Holt, Janet E

2017-01-01

Progression through the meiotic cell cycle must be strictly regulated in oocytes to generate viable embryos and offspring. During mitosis, the kinesin motor protein Kif4 is indispensable for chromosome condensation and separation, midzone formation and cytokinesis. Additionally, the bioactivity of Kif4 is dependent on phosphorylation via Aurora Kinase B and Cdk1, which regulate Kif4 function throughout mitosis. Here, we examine the role of Kif4 in mammalian oocyte meiosis. Kif4 localized in the cytoplasm throughout meiosis I and II, but was also observed to have a dynamic subcellular distribution, associating with both microtubules and kinetochores at different stages of development. Co-localization and proximity ligation assays revealed that the kinetochore proteins, CENP-C and Ndc80, are potential Kif4 interacting proteins. Functional analysis of Kif4 in oocytes via antisense knock-down demonstrated that this protein was not essential for meiosis I completion. However, Kif4 depleted oocytes displayed enlarged polar bodies and abnormal metaphase II spindles, indicating an essential role for this protein for correct asymmetric cell division in meiosis I. Further investigation of the phosphoregulation of meiotic Kif4 revealed that Aurora Kinase and Cdk activity is critical for Kif4 kinetochore localization and interaction with Ndc80 and CENP-C. Finally, Kif4 protein but not gene expression was found to be upregulated with age, suggesting a role for this protein in the decline of oocyte quality with age.

Regulation of Hyaluronan (HA) Metabolism Mediated by HYBID (Hyaluronan-binding Protein Involved in HA Depolymerization, KIAA1199) and HA Synthases in Growth Factor-stimulated Fibroblasts.

PubMed

Nagaoka, Aya; Yoshida, Hiroyuki; Nakamura, Sachiko; Morikawa, Tomohiko; Kawabata, Keigo; Kobayashi, Masaki; Sakai, Shingo; Takahashi, Yoshito; Okada, Yasunori; Inoue, Shintaro

2015-12-25

Regulation of hyaluronan (HA) synthesis and degradation is essential to maintenance of extracellular matrix homeostasis. We recently reported that HYBID (HYaluronan-Binding protein Involved in hyaluronan Depolymerization), also called KIAA1199, plays a key role in HA depolymerization in skin and arthritic synovial fibroblasts. However, regulation of HA metabolism mediated by HYBID and HA synthases (HASs) under stimulation with growth factors remains obscure. Here we report that TGF-β1, basic FGF, EGF, and PDGF-BB commonly enhance total amount of HA in skin fibroblasts through up-regulation of HAS expression, but molecular size of newly produced HA is dependent on HYBID expression levels. Stimulation of HAS1/2 expression and suppression of HYBID expression by TGF-β1 were abrogated by blockade of the MAPK and/or Smad signaling and the PI3K-Akt signaling, respectively. In normal human skin, expression of the TGF-β1 receptors correlated positively with HAS2 expression and inversely with HYBID expression. On the other hand, TGF-β1 up-regulated HAS1/2 expression but exerted only a slight suppressive effect on HYBID expression in synovial fibroblasts from the patients with osteoarthritis or rheumatoid arthritis, resulting in the production of lower molecular weight HA compared with normal skin and synovial fibroblasts. These data demonstrate that although TGF-β1, basic FGF, EGF, and PDGF-BB enhance HA production in skin fibroblasts, TGF-β1 most efficiently contributes to production of high molecular weight HA by HAS up-regulation and HYBID down-regulation and suggests that inefficient down-regulation of HYBID by TGF-β1 in arthritic synovial fibroblasts may be linked to accumulation of depolymerized HA in synovial fluids in arthritis patients. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Dysregulation of Uterine Signaling Pathways in Progesterone Receptor-Cre Knockout of Dicer

PubMed Central

Andreu-Vieyra, Claudia V.; Kim, Tae Hoon; Jeong, Jae-Wook; Hodgson, Myles C.; Chen, Ruihong; Creighton, Chad J.; Lydon, John P.; Gunaratne, Preethi H.; DeMayo, Francesco J.; Matzuk, Martin M.

2012-01-01

Epithelial-stromal interactions in the uterus are required for normal uterine functions such as pregnancy, and multiple signaling pathways are essential for this process. Although Dicer and microRNA (miRNA) have been implicated in several reproductive processes, the specific roles of Dicer and miRNA in uterine development are not known. To address the roles of miRNA in the regulation of key uterine pathways, we generated a conditional knockout of Dicer in the postnatal uterine epithelium and stroma using progesterone receptor-Cre. These Dicer conditional knockout females are sterile with small uteri, which demonstrate significant defects, including absence of glandular epithelium and enhanced stromal apoptosis, beginning at approximately postnatal d 15, with coincident expression of Cre and deletion of Dicer. Specific miRNA (miR-181c, −200b, −101, let-7d) were down-regulated and corresponding predicted proapoptotic target genes (Bcl2l11, Aldh1a3) were up-regulated, reflecting the apoptotic phenomenon. Although these mice had normal serum hormone levels, critical uterine signaling pathways, including progesterone-responsive genes, Indian hedgehog signaling, and the Wnt/β-catenin canonical pathway, were dysregulated at the mRNA level. Importantly, uterine stromal cell proliferation in response to progesterone was absent, whereas uterine epithelial cell proliferation in response to estradiol was maintained in adult uteri. These data implicate Dicer and appropriate miRNA expression as essential players in the regulation of multiple uterine signaling pathways required for uterine development and appropriate function. PMID:22798293

NF-κB Essential Modulator (NEMO) Is Critical for Thyroid Function.

PubMed

Reale, Carla; Iervolino, Anna; Scudiero, Ivan; Ferravante, Angela; D'Andrea, Luca Egildo; Mazzone, Pellegrino; Zotti, Tiziana; Leonardi, Antonio; Roberto, Luca; Zannini, Mariastella; de Cristofaro, Tiziana; Shanmugakonar, Muralitharan; Capasso, Giovambattista; Pasparakis, Manolis; Vito, Pasquale; Stilo, Romania

2016-03-11

The I-κB kinase (IKK) subunit NEMO/IKKγ (NEMO) is an adapter molecule that is critical for canonical activation of NF-κB, a pleiotropic transcription factor controlling immunity, differentiation, cell growth, tumorigenesis, and apoptosis. To explore the functional role of canonical NF-κB signaling in thyroid gland differentiation and function, we have generated a murine strain bearing a genetic deletion of the NEMO locus in thyroid. Here we show that thyrocyte-specific NEMO knock-out mice gradually develop hypothyroidism after birth, which leads to reduced body weight and shortened life span. Histological and molecular analysis indicate that absence of NEMO in thyrocytes results in a dramatic loss of the thyroid gland cellularity, associated with down-regulation of thyroid differentiation markers and ongoing apoptosis. Thus, NEMO-dependent signaling is essential for normal thyroid physiology. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Osteoblast-specific transcription factor Osterix (Osx) is an upstream regulator of Satb2 during bone formation.

PubMed

Tang, Wanjin; Li, Yang; Osimiri, Lindsey; Zhang, Chi

2011-09-23

Osterix (Osx) is an osteoblast-specific transcription factor essential for osteoblast differentiation and bone formation. Osx knock-out mice lack bone completely. Satb2 is critical for osteoblast differentiation as a special AT-rich binding transcription factor. It is not known how Satb2 is transcriptionally regulated during bone formation. In this study, quantitative real-time RT-PCR results demonstrated that Satb2 was down-regulated in Osx-null calvaria. In stable C2C12 mesenchymal cells using the tetracycline (Tet)-Off system, overexpression of Osx stimulated Satb2 expression. Moreover, inhibition of Osx by siRNA led to repression of Satb2 expression in osteoblasts. These results suggest that Osx controls Satb2 expression. Transient transfection assay showed that Osx activated 1kb Satb2 promoter reporter activity in a dose-dependent manner. To define the region of Satb2 promoter responsive to Osx activation, a series of deletion mutants of Satb2 constructs were made, and the minimal region was narrowed down to the proximal 130 bp of the Satb2 promoter. Further point mutation studies found that two GC-rich region mutations disrupted the Satb2 130bp promoter activation by Osx, suggesting that these GC-rich binding sites were responsible for Satb2 activation by Osx. Gel shift assay showed that Osx bound to the Satb2 promoter sequence directly. ChIP assays indicated that endogenous Osx associated with the native Satb2 promoter in osteoblasts. Importantly, Satb2 siRNA significantly inhibited Osx-induced osteoblast marker gene expressions. Taken together, our findings indicate that Osx is an upstream regulator of Satb2 during bone formation. This reveals a new additional link of the transcriptional regulation mechanism that Osx controls bone formation.

The effect of cannabichromene on adult neural stem/progenitor cells.

PubMed

Shinjyo, Noriko; Di Marzo, Vincenzo

2013-11-01

Apart from the psychotropic compound Δ(9)-tetrahydrocannabinol (THC), evidence suggests that other non-psychotropic phytocannabinoids are also of potential clinical use. This study aimed at elucidating the effect of major non-THC phytocannabinoids on the fate of adult neural stem progenitor cells (NSPCs), which are an essential component of brain function in health as well as in pathology. We tested three compounds: cannabidiol, cannabigerol, and cannabichromene (CBC), and found that CBC has a positive effect on the viability of mouse NSPCs during differentiation in vitro. The expression of NSPC and astrocyte markers nestin and Glial fibrillary acidic protein (GFAP), respectively, was up- and down-regulated, respectively. CBC stimulated ERK1/2 phosphorylation; however, this effect had a slower onset in comparison to typical MAPK stimulation. A MEK inhibitor, U0126, antagonized the up-regulation of nestin but not the down-regulation of GFAP. Based on a previous report, we studied the potential involvement of the adenosine A1 receptor in the effect of CBC on these cells and found that the selective adenosine A1 receptor antagonist, DPCPX, counteracted both ERK1/2 phosphorylation and up-regulation of nestin by CBC, indicating that also adenosine is involved in these effects of CBC, but possibly not in CBC inhibitory effect on GFAP expression. Next, we measured ATP levels as an equilibrium marker of adenosine and found higher ATP levels during differentiation of NSPCs in the presence of CBC. Taken together, our results suggest that CBC raises the viability of NSPCs while inhibiting their differentiation into astroglia, possibly through up-regulation of ATP and adenosine signalling. Copyright © 2013 Elsevier Ltd. All rights reserved.

Histone H2B monoubiquitination is involved in the regulation of cutin and wax composition in Arabidopsis thaliana.

PubMed

Ménard, Rozenn; Verdier, Gaëtan; Ors, Mareva; Erhardt, Mathieu; Beisson, Fred; Shen, Wen-Hui

2014-02-01

The plant cuticle is a chemically heterogeneous lipophilic layer composed of a cutin polymer matrix and waxes which covers the aerial parts of plants. This layer plays an essential role in the survival of plants by protecting them from desiccation and (a)biotic stresses. Knowledge on the gene networks and mechanisms regulating the synthesis of cuticle components during organ expansion or stress response remains limited however. Here, using five loss-of-function mutants for histone monoubiquitination, we report on the role of two RING E3 ligases, namely HISTONE MONOUBIQUITINATION 1 and 2 (HUB1 and HUB2), in the selective transcriptional activation of four cuticle biosynthesis genes in Arabidopsis thaliana. Microscopy observations showed that in hub1-6 and hub2-2 mutants irregular epidermal cells and disorganized cuticle layers were present in rosette leaves. Water loss measurements on excised rosettes demonstrated that cuticular permeability was significantly increased in the mutants. Chemical analysis of cuticle components revealed that the wax composition was changed and that cutin 16:0 dicarboxylic acid was significantly reduced in all hub mutants. Analysis of transcript levels of selected genes indicated that LACS2, ATT1 and HOTHEAD involved in cutin biosynthesis and CER1 involved in wax biosynthesis were down-regulated in the hub mutants, while the expression of LACERATA, CER3, CER6 and CER10 remained unchanged. Chromatin immunoprecipitation assays further showed that hub mutants are impaired in dynamic changes of histone H2B monoubiquitination at several loci of down-regulated genes. Taken together, these data establish that the regulation of cuticle composition involves chromatin remodeling by H2B monoubiquitination.

Copper Deficiency Leads to Anemia, Duodenal Hypoxia, Upregulation of HIF-2α and Altered Expression of Iron Absorption Genes in Mice

PubMed Central

Matak, Pavle; Zumerle, Sara; Mastrogiannaki, Maria; El Balkhi, Souleiman; Delga, Stephanie; Mathieu, Jacques R. R.; Canonne-Hergaux, François; Poupon, Joel; Sharp, Paul A.; Vaulont, Sophie; Peyssonnaux, Carole

2013-01-01

Iron and copper are essential trace metals, actively absorbed from the proximal gut in a regulated fashion. Depletion of either metal can lead to anemia. In the gut, copper deficiency can affect iron absorption through modulating the activity of hephaestin - a multi-copper oxidase required for optimal iron export from enterocytes. How systemic copper status regulates iron absorption is unknown. Mice were subjected to a nutritional copper deficiency-induced anemia regime from birth and injected with copper sulphate intraperitoneally to correct the anemia. Copper deficiency resulted in anemia, increased duodenal hypoxia and Hypoxia inducible factor 2α (HIF-2α) levels, a regulator of iron absorption. HIF-2α upregulation in copper deficiency appeared to be independent of duodenal iron or copper levels and correlated with the expression of iron transporters (Ferroportin - Fpn, Divalent Metal transporter – Dmt1) and ferric reductase – Dcytb. Alleviation of copper-dependent anemia with intraperitoneal copper injection resulted in down regulation of HIF-2α-regulated iron absorption genes in the gut. Our work identifies HIF-2α as an important regulator of iron transport machinery in copper deficiency. PMID:23555700

Insecticidal Activity of Melaleuca alternifolia Essential Oil and RNA-Seq Analysis of Sitophilus zeamais Transcriptome in Response to Oil Fumigation

PubMed Central

Liao, Min; Xiao, Jin-Jing; Zhou, Li-Jun; Liu, Yang; Wu, Xiang-Wei; Hua, Ri-Mao; Wang, Gui-Rong; Cao, Hai-Qun

2016-01-01

Background The cereal weevil, Sitophilus zeamais is one of the most destructive pests of stored cereals worldwide. Frequent use of fumigants for managing stored-product insects has led to the development of resistance in insects. Essential oils from aromatic plants including the tea oil plant, Melaleuca alternifolia may provide environmentally friendly alternatives to currently used pest control agents. However, little is known about molecular events involved in stored-product insects in response to plant essential oil fumigation. Results M. alternifolia essential oil was shown to possess the fumigant toxicity against S. zeamais. The constituent, terpinen-4-ol was the most effective compound for fumigant toxicity. M. alternifolia essential oil significantly inhibited the activity of three enzymes in S. zeamais, including two detoxifying enzymes, glutathione S-transferase (GST), and carboxylesterase (CarE), as well as a nerve conduction enzyme, acetylcholinesterase (AChE). Comparative transcriptome analysis of S. zeamais through RNA-Seq identified a total of 3,562 differentially expressed genes (DEGs), of which 2,836 and 726 were up-regulated and down-regulated in response to M. alternifolia essential oil fumigation, respectively. Based on gene ontology (GO) analysis, the majority of DEGs were involved in insecticide detoxification and mitochondrial function. Furthermore, an abundance of DEGs mapped into the metabolism pathway in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database were associated with respiration and metabolism of xenobiotics, including cytochrome P450s, CarEs, GSTs, and ATP-binding cassette transporters (ABC transporters). Some DEGs mapped into the proteasome and phagosome pathway were found to be significantly enriched. These results led us to propose a model of insecticide action that M. alternifolia essential oil likely directly affects the hydrogen carrier to block the electron flow and interfere energy synthesis in mitochondrial respiratory chain. Conclusion This is the first study to perform a comparative transcriptome analysis of S. zeamais in response to M. alternifolia essential oil fumigation. Our results provide new insights into the insecticidal mechanism of M. alternifolia essential oil fumigation against S. zeamais and eventually contribute to the management of this important agricultural pest. PMID:27936192

Insecticidal Activity of Melaleuca alternifolia Essential Oil and RNA-Seq Analysis of Sitophilus zeamais Transcriptome in Response to Oil Fumigation.

PubMed

Liao, Min; Xiao, Jin-Jing; Zhou, Li-Jun; Liu, Yang; Wu, Xiang-Wei; Hua, Ri-Mao; Wang, Gui-Rong; Cao, Hai-Qun

2016-01-01

The cereal weevil, Sitophilus zeamais is one of the most destructive pests of stored cereals worldwide. Frequent use of fumigants for managing stored-product insects has led to the development of resistance in insects. Essential oils from aromatic plants including the tea oil plant, Melaleuca alternifolia may provide environmentally friendly alternatives to currently used pest control agents. However, little is known about molecular events involved in stored-product insects in response to plant essential oil fumigation. M. alternifolia essential oil was shown to possess the fumigant toxicity against S. zeamais. The constituent, terpinen-4-ol was the most effective compound for fumigant toxicity. M. alternifolia essential oil significantly inhibited the activity of three enzymes in S. zeamais, including two detoxifying enzymes, glutathione S-transferase (GST), and carboxylesterase (CarE), as well as a nerve conduction enzyme, acetylcholinesterase (AChE). Comparative transcriptome analysis of S. zeamais through RNA-Seq identified a total of 3,562 differentially expressed genes (DEGs), of which 2,836 and 726 were up-regulated and down-regulated in response to M. alternifolia essential oil fumigation, respectively. Based on gene ontology (GO) analysis, the majority of DEGs were involved in insecticide detoxification and mitochondrial function. Furthermore, an abundance of DEGs mapped into the metabolism pathway in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database were associated with respiration and metabolism of xenobiotics, including cytochrome P450s, CarEs, GSTs, and ATP-binding cassette transporters (ABC transporters). Some DEGs mapped into the proteasome and phagosome pathway were found to be significantly enriched. These results led us to propose a model of insecticide action that M. alternifolia essential oil likely directly affects the hydrogen carrier to block the electron flow and interfere energy synthesis in mitochondrial respiratory chain. This is the first study to perform a comparative transcriptome analysis of S. zeamais in response to M. alternifolia essential oil fumigation. Our results provide new insights into the insecticidal mechanism of M. alternifolia essential oil fumigation against S. zeamais and eventually contribute to the management of this important agricultural pest.

Effect of Dietary Protein Level on the Expression of Proteins in the Gastrointestinal Tract of Young Pigs.

PubMed

Ma, Xianyong; Tian, Zhimei; Deng, Dun; Cui, Yiyan; Qiu, Yueqin

2018-05-02

The objective of this research is to investigate the effect of protein level on proteins expression in the gastrointestinal tract of young pigs. Eighteen piglets (Duroc × Landrace × Yorkshire) were weaned at 28 days of age and randomly assigned to three diets with 20%, 17%, and 14% CP level, and four essential amino acids, Lys, Met, Thr, and Trp, in three diets met the requirements of weaned piglets. The experimental period lasted 45 days. Compared with the control (20% CP level), the average daily feed intake, the average daily gain, and gain feed ratio of the 17% CP group did not decrease ( P > 0.05), but those of 14% CP group decreased ( P < 0.05). The proteomics profiles result of three tissues (gastric antrum, duodenum, and jejunum) showed that, compared with the control, the immune system, protein digestion and absorption, lipid or carbon digestion and absorption, etc. were up-regulated in 17% CP group, while most of them were down-regulated in 14% CP group. Amino acids metabolism of gastric, pancreatic secretion of duodenum or steroid hormone biosynthesis of jejunum was down-regulated in the 17% CP group, but the lipid metabolism was up-regulated in the 14% CP group. Six proteins were selected for identification by Western-blot, and their changes had the same trend as the proteomics results. The protein level decreased from 20% to 17%, the growth performance was not affected, while the nutrient digestion and absorption or the immune function were improved, which implied that 17% protein level maybe benefit for nutrients absorption of pigs.

Down-regulation of the sucrose transporters HvSUT1 and HvSUT2 affects sucrose homeostasis along its delivery path in barley grains.

PubMed

Radchuk, Volodymyr; Riewe, David; Peukert, Manuela; Matros, Andrea; Strickert, Marc; Radchuk, Ruslana; Weier, Diana; Steinbiß, Hans-Henning; Sreenivasulu, Nese; Weschke, Winfriede; Weber, Hans

2017-07-20

Sucrose transport and partitioning are crucial for seed filling. While many plasma-membrane-localised sucrose transporters (SUT1 family members) have been analysed in seeds, the functions of vacuolar SUT2 members are still obscure. In barley grains, expression of HvSUT1 and HvSUT2 overlap temporally and spatially, suggesting concerted functions to regulate sucrose homeostasis. Using HvSUT2-RNAi plants, we found that grains were also deficient in HvSUT1 expression and seemingly sucrose-limited during mid-to-late grain filling. Transgenic endosperms accumulated less starch and dry weight, although overall sucrose and hexose contents were higher. Comprehensive transcript and metabolite profiling revealed that genes related to glycolysis, the tricarboxylic acid cycle, starch and amino acid synthesis, grain maturation, and abscisic acid signalling were down-regulated together with most glycolytic intermediates and amino acids. Sucrose was increased along the sucrose delivery route in the nucellar projection, the endosperm transfer cells, and the starchy endosperm, indicating that suppressed transporter activity diminished sucrose efflux from vacuoles, which generated sugar deficiency in the cytoplasm. Thus, endosperm vacuoles may buffer sucrose concentrations to regulate homeostasis at grain filling. Transcriptional changes revealed that limited endosperm sucrose initiated sugar starvation responses, such as sugar recycling from starch, hemicelluloses and celluloses together with vacuolar protein degradation, thereby supporting formation of nucleotide sugars. Barley endosperm cells can thus suppress certain pathways to retrieve resources to maintain essential cell functions. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Modulation of tumor necrosis factor (TNF) receptor expression during monocytic differentiation by glucocorticoids.

PubMed

Goppelt-Struebe, M; Reiser, C O; Schneider, N; Grell, M

1996-10-01

Regulation of tumor necrosis factor receptors by glucocorticoids was investigated during phorbol ester-induced monocytic differentiation. As model system the human monocytic cell lines U937 and THP-1, which express both types of TNF receptors (TNF-R60 and TNF-R80), were differentiated with tetradecanoyl phorbol-13-acetate (TPA, 5 x 10(-9) M) in the presence or absence of dexamethasone (10(-9) - 10(-6) M). Expression of TNF receptors was determined at the mRNA level by Northern blot analysis and at the protein level by FACS analysis. During differentiation, TNF-R60 mRNA was down-regulated, whereas TNF-R80 mRNA levels were increased. Dexamethasone had no effect on TNF-R60 mRNA expression but attenuated TNF-R80 mRNA expression in both cell lines. Cell surface expression of TNF-R60 protein remained essentially unchanged during differentiation of THP-1 cells, whereas a rapid down-regulation of TNF-R80 was observed that was followed by a slow recovery. Surface expression of TNF-R80 was not affected by dexamethasone, whereas TNF-R60 expression was reduced by about 25%. These results indicate differential regulation of the two types of TNF receptors at the mRNA and protein level during monocytic differentiation. Glucocorticoids interfered with mRNA expression of TNF-R80 and protein expression of TNF-R60, but the rather limited effect leaves the question of its functional relevance open. In contrast to other cytokine systems, TNF receptors do not appear to be major targets of glucocorticoid action.

The MYB182 Protein Down-Regulates Proanthocyanidin and Anthocyanin Biosynthesis in Poplar by Repressing Both Structural and Regulatory Flavonoid Genes1[OPEN

PubMed Central

Yoshida, Kazuko; Ma, Dawei; Constabel, C. Peter

2015-01-01

Trees in the genus Populus (poplar) contain phenolic secondary metabolites including the proanthocyanidins (PAs), which help to adapt these widespread trees to diverse environments. The transcriptional activation of PA biosynthesis in response to herbivory and ultraviolet light stress has been documented in poplar leaves, and a regulator of this process, the R2R3-MYB transcription factor MYB134, has been identified. MYB134-overexpressing transgenic plants show a strong high-PA phenotype. Analysis of these transgenic plants suggested the involvement of additional MYB transcription factors, including repressor-like MYB factors. Here, MYB182, a subgroup 4 MYB factor, was found to act as a negative regulator of the flavonoid pathway. Overexpression of MYB182 in hairy root culture and whole poplar plants led to reduced PA and anthocyanin levels as well as a reduction in the expression of key flavonoid genes. Similarly, a reduced accumulation of transcripts of a MYB PA activator and a basic helix-loop-helix cofactor was observed in MYB182-overexpressing hairy roots. Transient promoter activation assays in poplar cell culture demonstrated that MYB182 can disrupt transcriptional activation by MYB134 and that the basic helix-loop-helix-binding motif of MYB182 was essential for repression. Microarray analysis of transgenic plants demonstrated that down-regulated targets of MYB182 also include shikimate pathway genes. This work shows that MYB182 plays an important role in the fine-tuning of MYB134-mediated flavonoid metabolism. PMID:25624398

Active Hexose-correlated Compound Down-regulates Heat Shock Factor 1, a Transcription Factor for HSP27, in Gemcitabine-resistant Human Pancreatic Cancer Cells.

PubMed

Tokunaga, Masayuki; Baron, Byron; Kitagawa, Takao; Tokuda, Kazuhiro; Kuramitsu, Yasuhiro

2015-11-01

Active hexose-correlated compound (AHCC) is an extract of a basidiomycete mushroom that enhances the therapeutic effects and reduces the side-effects of chemotherapy. Our previous studies demonstrated that heat-shock protein 27 (HSP27) was involved in gemcitabine-resistance of pancreatic cancer cells and it was down-regulated by AHCC-treatment. However, how AHCC down-regulated HSP27 is unknown. In the present study, we focused on two transcription factors reported to induce HSP27, heat shock factor 1 (HSF1) and high-mobility group box 1 (HMGB1) and investigated the effect of AHCC on their expression. KLM1-R cells were treated with AHCC and the protein expression of HSF1 and HMGB1 were analyzed by western blotting. The protein expression of HSF1 in KLM1-R was down-regulated by AHCC treatment. On the other hand, the protein expression of HMGB1 was not reduced in KLM1-R cells after AHCC treatment. The possibility that AHCC down-regulated HSP27 through down-regulation of the HSF1, was herein shown. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Disruption of mechanical stress in extracellular matrix is related to Stanford type A aortic dissection through down-regulation of Yes-associated protein.

PubMed

Jiang, Wen-Jian; Ren, Wei-Hong; Liu, Xu-Jie; Liu, Yan; Wu, Fu-Jian; Sun, Li-Zhong; Lan, Feng; Du, Jie; Zhang, Hong-Jia

2016-09-05

In this study, we assessed whether the down-regulation of Yes-associated protein (YAP) is involved in the pathogenesis of extracellular matrix (ECM) mechanical stress-induced Stanford type A aortic dissection (STAAD). Human aortic samples were obtained from heart transplantation donors as normal controls and from STAAD patients undergoing surgical replacement of the ascending aorta. Decreased maximum aortic wall velocity, ECM disorders, increased VSMC apoptosis, and YAP down-regulation were identified in STAAD samples. In a mouse model of STAAD, YAP was down-regulated over time during the development of ECM damage, and increased VSMC apoptosis was also observed. YAP knockdown induced VSMC apoptosis under static conditions in vitro , and the change in mechanical stress induced YAP down-regulation and VSMC apoptosis. This study provides evidence that YAP down-regulation caused by the disruption of mechanical stress is associated with the development of STAAD via the induction of apoptosis in aortic VSMCs. As STAAD is among the most elusive and life-threatening vascular diseases, better understanding of the molecular pathogenesis of STAAD is critical to improve clinical outcome.

Dual Bioactivities of Essential Oil Extracted from the Leaves of Artemisia argyi as an Antimelanogenic versus Antioxidant Agent and Chemical Composition Analysis by GC/MS

PubMed Central

Huang, Huey-Chun; Wang, Hsiao-Fen; Yih, Kuang-Hway; Chang, Long-Zen; Chang, Tsong-Min

2012-01-01

The study was aimed at investigating the antimelanogenic and antioxidant properties of essential oil when extracted from the leaves of Artemisia argyi, then analyzing the chemical composition of the essential oil. The inhibitory effect of the essential oil on melanogenesis was evaluated by a mushroom tyrosinase activity assay and B16F10 melanoma cell model. The antioxidant capacity of the essential oil was assayed by spectrophotometric analysis, and the volatile chemical composition of the essential oil was analyzed with gas chromatography-mass spectrometry (GC/MS). The results revealed that the essential oil significantly inhibits mushroom tyrosinase activity (IC50 = 19.16 mg/mL), down-regulates B16F10 intracellular tyrosinase activity and decreases the amount of melanin content in a dose-dependent pattern. Furthermore, the essential oil significantly scavenged 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzthiazoline- 6-sulphonic acid) ABTS radicals, showed an apparent reduction power as compared with metal-ion chelating activities. The chemicals constituents in the essential oil are ether (23.66%), alcohols (16.72%), sesquiterpenes (15.21%), esters (11.78%), monoterpenes (11.63%), ketones (6.09%), aromatic compounds (5.01%), and account for a 90.10% analysis of its chemical composition. It is predicted that eucalyptol and the other constituents, except for alcohols, in the essential oil may contribute to its antioxidant activities. The results indicated that essential oil extracted from A. argyi leaves decreased melanin production in B16F10 cells and showed potent antioxidant activity. The essential oil can thereby be applied as an inhibitor of melanogenesis and could also act as a natural antioxidant in skin care products. PMID:23203088

Dual bioactivities of essential oil extracted from the leaves of Artemisia argyi as an antimelanogenic versus antioxidant agent and chemical composition analysis by GC/MS.

PubMed

Huang, Huey-Chun; Wang, Hsiao-Fen; Yih, Kuang-Hway; Chang, Long-Zen; Chang, Tsong-Min

2012-11-12

The study was aimed at investigating the antimelanogenic and antioxidant properties of essential oil when extracted from the leaves of Artemisia argyi, then analyzing the chemical composition of the essential oil. The inhibitory effect of the essential oil on melanogenesis was evaluated by a mushroom tyrosinase activity assay and B16F10 melanoma cell model. The antioxidant capacity of the essential oil was assayed by spectrophotometric analysis, and the volatile chemical composition of the essential oil was analyzed with gas chromatography-mass spectrometry (GC/MS). The results revealed that the essential oil significantly inhibits mushroom tyrosinase activity (IC(50) = 19.16 mg/mL), down-regulates B16F10 intracellular tyrosinase activity and decreases the amount of melanin content in a dose-dependent pattern. Furthermore, the essential oil significantly scavenged 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) ABTS radicals, showed an apparent reduction power as compared with metal-ion chelating activities. The chemicals constituents in the essential oil are ether (23.66%), alcohols (16.72%), sesquiterpenes (15.21%), esters (11.78%), monoterpenes (11.63%), ketones (6.09%), aromatic compounds (5.01%), and account for a 90.10% analysis of its chemical composition. It is predicted that eucalyptol and the other constituents, except for alcohols, in the essential oil may contribute to its antioxidant activities. The results indicated that essential oil extracted from A. argyi leaves decreased melanin production in B16F10 cells and showed potent antioxidant activity. The essential oil can thereby be applied as an inhibitor of melanogenesis and could also act as a natural antioxidant in skin care products.

An fMRI investigation of the cognitive reappraisal of negative memories

PubMed Central

Holland, Alisha C.; Kensinger, Elizabeth A.

2013-01-01

Episodic memory retrieval can be influenced by individuals’ current goals, including those that are emotional in nature. Participants underwent an fMRI scan while reappraising, or changing the way they thought about aversive images they had previously encoded, to down-regulate (i.e., decrease), up-regulate (i.e., increase), or maintain the emotional intensity associated with their recall. A conjunction analysis between down- and up-regulation during the entire 12-sec recall period revealed that both commonly activated reappraisal-related regions, particularly in the lateral and medial prefrontal cortex (PFC). However, when we analyzed a reappraisal instruction phase prior to recall and then divided the recall phase into the time when individuals were first searching for their memories and later elaborating on their details, we found that down- and up-regulation engaged greater neural activity at different time points. Up-regulation engaged greater PFC activity than down-regulation or maintenance during the reappraisal instruction phase. In contrast, down-regulation engaged greater lateral PFC activity as images were being searched for and retrieved. Maintaining the emotional intensity associated with the aversive images engaged similar regions to a greater extent than either reappraisal condition as participants elaborated on the details of the images they were holding in mind. Our findings suggest that down- and up-regulation engage similar neural regions during memory retrieval, but differ in the timing of this engagement. PMID:23500898

Disruptive environmental chemicals and cellular mechanisms that confer resistance to cell death

PubMed Central

Narayanan, Kannan Badri; Ali, Manaf; Barclay, Barry J.; Cheng, Qiang (Shawn); D’Abronzo, Leandro; Dornetshuber-Fleiss, Rita; Ghosh, Paramita M.; Gonzalez Guzman, Michael J.; Lee, Tae-Jin; Leung, Po Sing; Li, Lin; Luanpitpong, Suidjit; Ratovitski, Edward; Rojanasakul, Yon; Romano, Maria Fiammetta; Romano, Simona; Sinha, Ranjeet K.; Yedjou, Clement; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Amedei, Amedeo; Brown, Dustin G.; Ryan, Elizabeth P.; Colacci, Anna Maria; Hamid, Roslida A.; Mondello, Chiara; Raju, Jayadev; Salem, Hosni K.; Woodrick, Jordan; Scovassi, A.Ivana; Singh, Neetu; Vaccari, Monica; Roy, Rabindra; Forte, Stefano; Memeo, Lorenzo; Kim, Seo Yun; Bisson, William H.; Lowe, Leroy; Park, Hyun Ho

2015-01-01

Cell death is a process of dying within biological cells that are ceasing to function. This process is essential in regulating organism development, tissue homeostasis, and to eliminate cells in the body that are irreparably damaged. In general, dysfunction in normal cellular death is tightly linked to cancer progression. Specifically, the up-regulation of pro-survival factors, including oncogenic factors and antiapoptotic signaling pathways, and the down-regulation of pro-apoptotic factors, including tumor suppressive factors, confers resistance to cell death in tumor cells, which supports the emergence of a fully immortalized cellular phenotype. This review considers the potential relevance of ubiquitous environmental chemical exposures that have been shown to disrupt key pathways and mechanisms associated with this sort of dysfunction. Specifically, bisphenol A, chlorothalonil, dibutyl phthalate, dichlorvos, lindane, linuron, methoxychlor and oxyfluorfen are discussed as prototypical chemical disruptors; as their effects relate to resistance to cell death, as constituents within environmental mixtures and as potential contributors to environmental carcinogenesis. PMID:26106145

The medial prefrontal and orbitofrontal cortices differentially regulate dopamine system function.

PubMed

Lodge, Daniel J

2011-05-01

The prefrontal cortex (PFC) is essential for top-down control over higher-order executive function. In this study we demonstrate that the medial prefrontal cortex (mPFC) and orbitofrontal cortex (OFC) differentially regulate VTA dopamine neuron activity, and furthermore, the pattern of activity in the PFC drastically alters the dopamine neuron response. Thus, although single-pulse activation of the mPFC either excites or inhibits equivalent numbers of dopamine neurons, activation of the OFC induces a primarily inhibitory response. Moreover, activation of the PFC with a pattern that mimics spontaneous burst firing of pyramidal neurons produces a strikingly different response. Specifically, burst-like activation of the mPFC induces a massive increase in dopamine neuron firing, whereas a similar pattern of OFC activation largely inhibits dopamine activity. Taken together, these data demonstrate that the mPFC and OFC differentially regulate dopamine neuron activity, and that the pattern of cortical activation is critical for determining dopamine system output.

Steroid hormone induction of temporal gene expression in Drosophila brain neuroblasts generates neuronal and glial diversity.

PubMed

Syed, Mubarak Hussain; Mark, Brandon; Doe, Chris Q

2017-04-10

An important question in neuroscience is how stem cells generate neuronal diversity. During Drosophila embryonic development, neural stem cells (neuroblasts) sequentially express transcription factors that generate neuronal diversity; regulation of the embryonic temporal transcription factor cascade is lineage-intrinsic. In contrast, larval neuroblasts generate longer ~50 division lineages, and currently only one mid-larval molecular transition is known: Chinmo/Imp/Lin-28+ neuroblasts transition to Syncrip+ neuroblasts. Here we show that the hormone ecdysone is required to down-regulate Chinmo/Imp and activate Syncrip, plus two late neuroblast factors, Broad and E93. We show that Seven-up triggers Chinmo/Imp to Syncrip/Broad/E93 transition by inducing expression of the Ecdysone receptor in mid-larval neuroblasts, rendering them competent to respond to the systemic hormone ecdysone. Importantly, late temporal gene expression is essential for proper neuronal and glial cell type specification. This is the first example of hormonal regulation of temporal factor expression in Drosophila embryonic or larval neural progenitors.

Epigenetic down-regulated DDX10 promotes cell proliferation through Akt/NF-κB pathway in ovarian cancer

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

Gai, Muhuizi; Bo, Qifang; Qi, Lixia, E-mail: lixiaqi_dph@sina.com

Ovarian cancer contributes to the majority of ovarian cancer, while the molecular mechanisms remain elusive. Recently, some DEAD box protein 1 has been reported play a tumor suppressor role in ovarian cancer progression. However, the functions of DEAD box protein (DDX) members in ovarian cancer development remain largely unknown. In current study, we retrieved GEO databases and surprisingly found that DDX10 is significantly down-regulated in ovarian cancer tissues compared with normal ovary. These findings suggest that DDX10 might also play a suppressive role in ovarian cancer. We then validated the down-regulated expression pattern of DDX10 in fresh ovarian cancer tissues.more » Furthermore, both loss- and gain-functions assays reveal that the down-regulated DDX10 could promote ovarian cancer proliferation in vitro and the xenograft subcutaneous tumor formation assays confirmed these findings in vivo. In addition, we found that DDX10 is epigenetic silenced by miR-155-5p in ovarian cancer. Moreover, we further preliminary illustrated that down-regulated DDX10 promotes ovarian cancer cell proliferation through Akt/NF-κB pathway. Taken together, in current study, we found a novel tumor suppressor, DDX10, is epigenetic silenced by miR-155-5p in ovarian cancer, and the down-regulated expression pattern of DDX10 promotes ovarian cancer proliferation through Akt/NF-κB pathway. Our findings shed the light that DDX families might be a novel for ovarian cancer treatment. - Highlights: • A novel DEAD box protein, DDX10 is significantly down-regulated in ovarian cancer tissues. • Down-regulated DDX10 promotes ovarian cancer cell proliferation and growth both in vitro and in vivo. • miR-155-5p is highly expressed in ovarian cancer tissues and epigenetically targets DDX10. • DDX10 and miR-155-5p regulates Akt/p65 axis in ovarian cancer cells.« less

Heart rate variability indices as bio-markers of top-down self-regulatory mechanisms: A meta-analytic review.

PubMed

Holzman, Jacob B; Bridgett, David J

2017-03-01

Theoretical perspectives posit that heart-rate variability (HRV) reflects self-regulatory capacity and therefore can be employed as a bio-marker of top-down self-regulation (the ability to regulate behavioral, cognitive, and emotional processes). However, existing findings of relations between self-regulation and HRV indices are mixed. To clarify the nature of such relations, we conducted a meta-analysis of 123 studies (N=14,347) reporting relations between HRV indices and aspects of top-down self-regulation (e.g., executive functioning, emotion regulation, effortful control). A significant, albeit small, effect was observed (r=0.09) such that greater HRV was related to better top-down self-regulation. Differences in relations were negligible across aspects of self-regulation, self-regulation measurement methods, HRV computational techniques, at-risk compared with healthy samples, and the context of HRV measurement. Stronger relations were observed in older relative to younger samples and in published compared to unpublished studies. These findings generally support the notion that HRV indices can tentatively be employed as bio-markers of top-down self-regulation. Conceptual and theoretical implications, and critical gaps in current knowledge to be addressed by future work, are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Rhythmic control of endocannabinoids in the rat pineal gland.

PubMed

Koch, Marco; Ferreirós, Nerea; Geisslinger, Gerd; Dehghani, Faramarz; Korf, Horst-Werner

2015-01-01

Endocannabinoids modulate neuroendocrine networks by directly targeting cannabinoid receptors. The time-hormone melatonin synchronizes these networks with external light condition and guarantees time-sensitive and ecologically well-adapted behaviors. Here, the endocannabinoid arachidonoyl ethanolamide (AEA) showed rhythmic changes in rat pineal glands with higher levels during the light-period and reduced amounts at the onset of darkness. Norepinephrine, the essential stimulus for nocturnal melatonin biosynthesis, acutely down-regulated AEA and other endocannabinoids in cultured pineal glands. These temporal dynamics suggest that AEA exerts time-dependent autocrine and/or paracrine functions within the pineal. Moreover, endocananbinoids may be released from the pineal into the CSF or blood stream.

[Rotten meat, coffee with corn, and watered-down milk: power struggles and oversight of the food trade in the Imperial Court, 1840-1889].

PubMed

Souza, Juliana Teixeira

2011-12-01

During the Second Reign, the regulation and inspection of food trade in the city of Rio de Janeiro were characterized by heated clashes between three agencies that had overlapping powers in the matter: the Câmara Municipal (Municipal Chambers), the Secretaria de Polícia (Police Department), and the Junta Central de Higiene Pública (Central Public Hygiene Board). The article analyzes the conflicts between these agencies, while taking into account their coincidental duties and power disputes and also underscoring the Chamber's effort to preserve its former public health responsibilities, essential to protecting its governmental capacities.

Knockdown of mortalin within the medial prefrontal cortex impairs normal sensorimotor gating.

PubMed

Gabriele, Nicole; Pontoriero, Giuseppe F; Thomas, Nancy; Shethwala, Shazli K; Pristupa, Zdenek B; Gabriele, Joseph P

2010-11-01

The 70-kDa mitochondrial heat shock protein, mortalin, is a ubiquitously expressed, multifunctional protein that is capable of binding the neurotransmitter, dopamine, within the brain. Dopamine dysregulation has been implicated in many of the abnormal neurological behaviors. Although studies have indicated that mortalin is differentially regulated in response to dopaminergic modulation, research has yet to elucidate the role of mortalin in the regulation of dopaminergic activity. This study seeks to investigate the role of mortalin in the regulation of dopamine-dependent behavior, specifically as it pertains to schizophrenia (SCZ). Mortalin expression was knocked down through the infusion of antisense oligodeoxynucleotide molecules into the medial prefrontal cortex (mPFC). Rats infused with mortalin antisense oligodeoxynucleotide molecules exhibited significant prepulse inhibition deficits, suggestive of defects in normal sensorimotor gating. Furthermore, mortalin misexpression within the mPFC was coupled to a significant increase in mortalin protein expression within the nucleus accumbens at the molecular level. These findings demonstrate that mortalin plays an essential role in the regulation of dopamine-dependent behavior and plays an even greater role in the pathogenesis of SCZ.

Down-regulation of IL-8 by high-dose vitamin D is specific to hyperinflammatory macrophages and involves mechanisms beyond up-regulation of DUSP1

PubMed Central

Dauletbaev, N; Herscovitch, K; Das, M; Chen, H; Bernier, J; Matouk, E; Bérubé, J; Rousseau, S; Lands, L C

2015-01-01

Background and Purpose There is current interest in vitamin D as a potential anti-inflammatory treatment for chronic inflammatory lung disease, including cystic fibrosis (CF). Vitamin D transcriptionally up-regulates the anti-inflammatory gene DUSP1, which partly controls production of the inflammatory chemokine IL-8. IL-8 is overabundant in CF airways, potentially due to hyperinflammatory responses of CF macrophages. We tested the ability of vitamin D metabolites to down-regulate IL-8 production in CF macrophages. Experimental Approach CF and healthy monocyte-derived macrophages (MDM) were treated with two vitamin D metabolites, 25-hydroxyvitamin D3 (25OHD3) and 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), or paricalcitol, synthetic analogue of 1,25(OH)2D3. 25OHD3 was tested at doses of 25–150 nM, whereas 1,25(OH)2D3 and paricalcitol at doses of up to 100 nM. IL-8 was stimulated by bacterial virulence factors. As potential anti-inflammatory mechanism of vitamin D metabolites, we assessed up-regulation of DUSP1. Key Results MDM from patients with CF and some healthy donors showed excessive production of stimulated IL-8, highlighting their hyperinflammatory phenotype. Vitamin D metabolites down-regulated stimulated IL-8 only in those hyperinflammatory MDM, and only when used at high doses (>100 nM for 25OHD3, or >1 nM for 1,25(OH)2D3 and paricalcitol). The magnitude of IL-8 down-regulation by vitamin D metabolites or paricalcitol was moderate (∼30% vs. >70% by low-dose dexamethasone). Transcriptional up-regulation of DUSP1 by vitamin D metabolites was seen in all tested MDM, regardless of IL-8 down-regulation. Conclusions and Implications Vitamin D metabolites and their analogues moderately down-regulate IL-8 in hyperinflammatory macrophages, including those from CF. This down-regulation appears to go through DUSP1-independent mechanisms. PMID:26178144

Down-regulation of IL-8 by high-dose vitamin D is specific to hyperinflammatory macrophages and involves mechanisms beyond up-regulation of DUSP1.

PubMed

Dauletbaev, N; Herscovitch, K; Das, M; Chen, H; Bernier, J; Matouk, E; Bérubé, J; Rousseau, S; Lands, L C

2015-10-01

There is current interest in vitamin D as a potential anti-inflammatory treatment for chronic inflammatory lung disease, including cystic fibrosis (CF). Vitamin D transcriptionally up-regulates the anti-inflammatory gene DUSP1, which partly controls production of the inflammatory chemokine IL-8. IL-8 is overabundant in CF airways, potentially due to hyperinflammatory responses of CF macrophages. We tested the ability of vitamin D metabolites to down-regulate IL-8 production in CF macrophages. CF and healthy monocyte-derived macrophages (MDM) were treated with two vitamin D metabolites, 25-hydroxyvitamin D3 (25OHD3 ) and 1,25-dihydroxyvitamin D3 (1,25(OH)2 D3 ), or paricalcitol, synthetic analogue of 1,25(OH)2 D3 . 25OHD3 was tested at doses of 25-150 nM, whereas 1,25(OH)2 D3 and paricalcitol at doses of up to 100 nM. IL-8 was stimulated by bacterial virulence factors. As potential anti-inflammatory mechanism of vitamin D metabolites, we assessed up-regulation of DUSP1. MDM from patients with CF and some healthy donors showed excessive production of stimulated IL-8, highlighting their hyperinflammatory phenotype. Vitamin D metabolites down-regulated stimulated IL-8 only in those hyperinflammatory MDM, and only when used at high doses (>100 nM for 25OHD3 , or >1 nM for 1,25(OH)2 D3 and paricalcitol). The magnitude of IL-8 down-regulation by vitamin D metabolites or paricalcitol was moderate (∼30% vs. >70% by low-dose dexamethasone). Transcriptional up-regulation of DUSP1 by vitamin D metabolites was seen in all tested MDM, regardless of IL-8 down-regulation. Vitamin D metabolites and their analogues moderately down-regulate IL-8 in hyperinflammatory macrophages, including those from CF. This down-regulation appears to go through DUSP1-independent mechanisms. © 2015 The British Pharmacological Society.

Effects of coumarate 3-hydroxylase down-regulation on lignin structure

Treesearch

John Ralph; Takuya Akiyama; Hoon Kim; Fachuang Lu; Paul F. Schatz; Jane M. Marita; Sally A. Ralph; M.S. Srinivasa Reddy; Fang Chen; Richard A. Dixon

2006-01-01

Down-regulation of the gene encoding 4-coumarate 3-hydroxylase (C3H) in alfalfa massively but predictably increased the proportion of p-hydroxyphenyl (P) units relative to thenormally dominant guaiacyl (G) and syringyl (S) units Stem levels of up to ~65% P (from wild-type levels of ~1%) resulting from down-regulation of C3H were measured by traditional degradative...

The role of sink strength and nitrogen availability in the down-regulation of photosynthetic capacity in field-grown Nicotiana tabacum at elevated CO2 concentration

USDA-ARS?s Scientific Manuscript database

Down-regulation of photosynthesis is one of the most frequent responses observed in C3 plants grown under elevated atmospheric CO2 concentration ([CO2]). Down-regulation is often attributed to an insufficient capacity of sink organs to use or store the increase in carbohydrate production in leaves t...

Klotho down-regulates Egr-1 by inhibiting TGF-β1/Smad3 signaling in high glucose treated human mesangial cells

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

Li, Yang; Department of Geriatrics, Zhu Jiang Hospital, Southern Medical University, Guangzhou, Guangdong; Hu, Fang

Diabetic kidney disease (DKD) has become the leading cause of end-stage renal disease worldwide and is associated with glomerular mesangial cell (MC) proliferation and excessive extracellular matrix (ECM) production. Klotho can attenuate renal fibrosis in part by inhibiting TGF-β1/Smad3 signaling in DKD. Early growth response factor 1 (Egr-1) has been shown to play a key role in renal fibrosis in part by facilitating the formation of a positive feedback loop involving TGF-β1. However, whether Klotho down-regulates Egr-1 by inhibiting TGF-β1/Smad3 signaling in DKD is unclear. In the present study, we assessed human MCs that were incubated under high-glucose conditions tomore » mimic diabetes. Then, we transfected the cells with Klotho plasmid or siRNA to overexpress or knock down Klotho gene and protein expression. Klotho, Egr-1, fibronectin (FN), collagen type I (Col I), Smad3 and phosphorylated Smad3 (p-Smad3) gene and protein expression levels were determined by RT-qPCR and western blotting respectively. High glucose time-dependently down-regulated Klotho mRNA and protein expression in cultured human MCs. pcDNA3.1-Klotho transfection-mediated Klotho overexpression down-regulated Egr-1, FN and Col I expression and the p-Smad3/Smad3 ratio in human MCs. Conversely, siRNA-mediated Klotho silencing up-regulated Egr-1, FN, and Col I expression and the p-Smad3/Smad3 ratio. Moreover, the effects of si-Klotho on Egr-1 expression were abolished by the TGF-β1 inhibitor SB-431542. Klotho overexpression can prevent mesangial ECM production in high-glucose-treated human MCs, an effect that has been partially attributed to Egr-1 down-regulation facilitated by TGF-β1/Smad3 signaling inhibition. - Highlights: • High glucose time-dependently down-regulated Klotho mRNA and protein expression in cultured human MCs. • Klotho overexpression down-regulated Egr-1 and prevented mesangial ECM production in high-glucose-treated human MCs. • Klotho down-regulated Egr-1 by inhibiting TGF-β1/Smad3 signaling in high-glucose-treated human MCs.« less

Investigation of mechanisms of mesenchymal stem cells for treatment of diabetic nephropathy via construction of a miRNA-TF-mRNA network

PubMed Central

Yang, Hailing; Zhang, Xiaofei; Xin, Guangda

2018-01-01

Abstract Background: Recent studies have reported that mesenchymal stem cells (MSCs) exert therapeutic effects on the treatment of diabetic nephropathy (DN), but the underlying mechanisms remain unclear. Methods: A dataset GSE65561 was obtained from Gene Expression Omnibus (GEO) database, which contained four healthy control samples (group 1), four healthy controls samples co-cultured with MSCs (group 2), five DN samples (group 3) and five DN samples co-cultured with MSCs (group 4). The differentially expressed genes (DEGs) between group 3 vs. group 1 and group 4 vs. group 2 were constructed using Linear Models for Microarray (LIMMA) package package. Then, DAVID was used to analyze the functional enrichment of DEGs. Based on STRING database the protein-protein interaction (PPI) network was visualized by the Cytoscape plug-in CytoNCA. Besides, the hub miRNAs and transcription factors (TFs) regulating DEGs were predicted using Webgestalt. Results: Totally, 303 up-regulated and 88 down-regulated DEGs were shared in group 3 vs. group 1 and group 4 vs. group 2. Besides, the up-regulated DEGs were mainly enriched in ‘translation’ and ‘translational elongation’, while the down-regulated genes were only enriched in ‘protein kinase activity’. RPS27A and RPLP0 had a higher degree in the PPI network and they were regulated by EIF3M. In addition, ETF1 was predicted to be an important gene, which was regulated by miR-150, miR-134 and EIF2S1. Conclusions: RPS27A, RPLP0 and ETF1 may be potential targets for MSCs on the treatment of DN.HighlightsRPS27A and RPLP0 may be important genes in the treatment of MSCs for DN.TF EIF3M may play a key role in the treatment of MSCs for DN.MiR-150 and miR-134 may be essential microRNAs in the treatment of MSCs for DN. PMID:29532746

Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus Nsp4 Cleaves VISA to Impair Antiviral Responses Mediated by RIG-I-like Receptors.

PubMed

Huang, Chen; Du, Yinping; Yu, Zhibin; Zhang, Qiong; Liu, Yihao; Tang, Jun; Shi, Jishu; Feng, Wen-Hai

2016-06-22

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most significant etiological agents in the swine industry worldwide. It has been reported that PRRSV infection can modulate host immune responses, and innate immune evasion is thought to play a vital role in PRRSV pathogenesis. In this study, we demonstrated that highly pathogenic PRRSV (HP-PRRSV) infection specifically down-regulated virus-induced signaling adaptor (VISA), a unique adaptor molecule that is essential for retinoic acid induced gene-I (RIG-I) and melanoma differentiation associated gene 5 (MDA5) signal transduction. Moreover, we verified that nsp4 inhibited IRF3 activation induced by signaling molecules, including RIG-I, MDA5, VISA, and TBK1, but not IRF3. Subsequently, we demonstrated that HP-PRRSV nsp4 down-regulated VISA and suppressed type I IFN induction. Importantly, VISA was cleaved by nsp4 and released from mitochondrial membrane, which interrupted the downstream signaling of VISA. However, catalytically inactive mutant of nsp4 abolished its ability to cleave VISA. Interestingly, nsp4 of typical PRRSV strain CH-1a had no effect on VISA. Taken together, these findings reveal a strategy evolved by HP-PRRSV to counteract anti-viral innate immune signaling, which complements the known PRRSV-mediated immune-evasion mechanisms.

RNAi Experiments in D. melanogaster: Solutions to the Overlooked Problem of Off-Targets Shared by Independent dsRNAs

PubMed Central

Seinen, Erwin; Burgerhof, Johannes G. M.; Jansen, Ritsert C.; Sibon, Ody C. M.

2010-01-01

Background RNAi technology is widely used to downregulate specific gene products. Investigating the phenotype induced by downregulation of gene products provides essential information about the function of the specific gene of interest. When RNAi is applied in Drosophila melanogaster or Caenorhabditis elegans, often large dsRNAs are used. One of the drawbacks of RNAi technology is that unwanted gene products with sequence similarity to the gene of interest can be down regulated too. To verify the outcome of an RNAi experiment and to avoid these unwanted off-target effects, an additional non-overlapping dsRNA can be used to down-regulate the same gene. However it has never been tested whether this approach is sufficient to reduce the risk of off-targets. Methodology We created a novel tool to analyse the occurance of off-target effects in Drosophila and we analyzed 99 randomly chosen genes. Principal Findings Here we show that nearly all genes contain non-overlapping internal sequences that do show overlap in a common off-target gene. Conclusion Based on our in silico findings, off-target effects should not be ignored and our presented on-line tool enables the identification of two RNA interference constructs, free of overlapping off-targets, from any gene of interest. PMID:20957038

Down Syndrome: A Cardiovascular Perspective

ERIC Educational Resources Information Center

Vis, J. C.; Duffels, M. G. J.; Winter, M. M.; Weijerman, M. E.; Cobben, J. M.; Huisman, S. A.; Mulder, B. J. M.

2009-01-01

This review focuses on the heart and vascular system in patients with Down syndrome. A clear knowledge on the wide spectrum of various abnormalities associated with this syndrome is essential for skillful management of cardiac problems in patients with Down syndrome. Epidemiology of congenital heart defects, cardiovascular aspects and…

Large-scale label-free comparative proteomics analysis of polo-like kinase 1 inhibition via the small-molecule inhibitor BI 6727 (Volasertib) in BRAF(V600E) mutant melanoma cells.

PubMed

Cholewa, Brian D; Pellitteri-Hahn, Molly C; Scarlett, Cameron O; Ahmad, Nihal

2014-11-07

Polo-like kinase 1 (Plk1) is a serine/threonine kinase that plays a key role during the cell cycle by regulating mitotic entry, progression, and exit. Plk1 is overexpressed in a variety of human cancers and is essential to sustained oncogenic proliferation, thus making Plk1 an attractive therapeutic target. However, the clinical efficacy of Plk1 inhibition has not emulated the preclinical success, stressing an urgent need for a better understanding of Plk1 signaling. This study addresses that need by utilizing a quantitative proteomics strategy to compare the proteome of BRAF(V600E) mutant melanoma cells following treatment with the Plk1-specific inhibitor BI 6727. Employing label-free nano-LC-MS/MS technology on a Q-exactive followed by SIEVE processing, we identified more than 20 proteins of interest, many of which have not been previously associated with Plk1 signaling. Here we report the down-regulation of multiple metabolic proteins with an associated decrease in cellular metabolism, as assessed by lactate and NAD levels. Furthermore, we have also identified the down-regulation of multiple proteasomal subunits, resulting in a significant decrease in 20S proteasome activity. Additionally, we have identified a novel association between Plk1 and p53 through heterogeneous ribonucleoprotein C1/C2 (hnRNPC), thus providing valuable insight into Plk1's role in cancer cell survival.

Triptolide disrupts the actin-based Sertoli-germ cells adherens junctions by inhibiting Rho GTPases expression

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

Wang, Xiang; Zhao, Fang

Triptolide (TP), derived from the medicinal plant Triterygium wilfordii Hook. f. (TWHF), is a diterpene triepoxide with variety biological and pharmacological activities. However, TP has been restricted in clinical application due to its narrow therapeutic window especially in reproductive system. During spermatogenesis, Sertoli cell cytoskeleton plays an essential role in facilitating germ cell movement and cell-cell actin-based adherens junctions (AJ). At Sertoli cell-spermatid interface, the anchoring device is a kind of AJ, known as ectoplasmic specializations (ES). In this study, we demonstrate that β-actin, an important component of cytoskeleton, has been significantly down-regulated after TP treatment. TP can inhibit themore » expression of Rho GTPase such as, RhoA, RhoB, Cdc42 and Rac1. Downstream of Rho GTPase, Rho-associated protein kinase (ROCKs) gene expressions were also suppressed by TP. F-actin immunofluorescence proved that TP disrupts Sertoli cells cytoskeleton network. As a result of β-actin down-regulation, TP treatment increased expression of testin, which indicating ES has been disassembled. In summary, this report illustrates that TP induces cytoskeleton dysfunction and disrupts cell-cell adherens junctions via inhibition of Rho GTPases. - Highlights: • Triptolide induced the disruption of Sertoli-germ cell adherens junction. • Rho GTPases expression and actin dynamics have been suppressed by triptolide. • Actin-based adherens junction is a potential antifertility target of triptolide. • Rho-Rock is involved in the regulation of actin dynamics.« less

Adult Kawasaki's disease with myocarditis, splenomegaly, and highly elevated serum ferritin levels.

PubMed

Cunha, Burke A; Pherez, Francisco M; Alexiadis, Varvara; Gagos, Marios; Strollo, Stephanie

2010-01-01

Kawasaki's disease is a disease of unknown cause. The characteristic clinical features of Kawasaki's disease are fever> or =102 degrees F for> or =5 days accompanied by a bilateral bulbar conjunctivitis/conjunctival suffusion, erythematous rash, cervical adenopathy, pharyngeal erythema, and swelling of the dorsum of the hands/feet. Kawasaki's disease primarily affects children and is rare in adults. In children, Kawasaki's disease is more likely to be associated with aseptic meningitis, coronary artery aneurysms, and thrombocytosis. In adult Kawasaki's disease, unilateral cervical adenopathy, arthritis, conjunctival suffusion/conjunctivitis, and elevated serum transaminases (serum glutamic oxaloacetic transaminase [SGOT]/serum glutamate pyruvate transaminase [SGPT]) are more likely. Kawasaki's disease in adults may be mimicked by other acute infections with fever and rash, that is, group A streptococcal scarlet fever, toxic shock syndrome (TSS), and Rocky Mountain Spotted Fever (RMSF). Because there are no specific tests for Kawasaki's disease, diagnosis is based on clinical criteria and the syndromic approach. In addition to rash and fever, scarlet fever is characterized by circumoral pallor, oropharyngeal edema, Pastia's lines, and peripheral eosinophilia, but not conjunctival suffusion, splenomegaly, swelling of the dorsum of the hands/feet, thrombocytosis, or an elevated SGOT/SGPT. In TSS, in addition to rash and fever, there is conjunctival suffusion, oropharyngeal erythema, and edema of the dorsum of the hands/feet, an elevated SGOT/SGPT, and thrombocytopenia. Patients with TSS do not have cervical adenopathy or splenomegaly. RMSF presents with fever and a maculopapular rash that becomes petechial, first appearing on the wrists/ankles after 3 to 5 days. RMSF is accompanied by a prominent headache, periorbital edema, conjunctival suffusion, splenomegaly, thrombocytopenia, an elevated SGOT/SGPT, swelling of the dorsum of the hands/feet, but not oropharyngeal erythema. We present a case of adult Kawasaki's disease with myocarditis and splenomegaly. The patient's myocarditis rapidly resolved, and he did not develop coronary artery aneurysms. In addition to splenomegaly, this case of adult Kawasaki's disease is remarkable because the patient had highly elevated serum ferritin levels of 944-1303 ng/mL; (normal<189 ng/mL). To the best of our knowledge, this is the first report of adult Kawasaki's disease with highly elevated serum ferritin levels. This is also the first report of splenomegaly in adult Kawasaki's disease. We conclude that Kawasaki's disease should be considered in the differential diagnosis in adult patients with rash/fever for> or =5 days with conjunctival suffusion, cervical adenopathy, swelling of the dorsum of the hands/feet, thrombocytosis and otherwise unexplained highly elevated ferritin levels. Copyright 2010 Elsevier Inc. All rights reserved.

The influence of emotion down-regulation on the expectation of sexual reward.

PubMed

Brom, Mirte; Laan, Ellen; Everaerd, Walter; Spinhoven, Philip; Cousijn, Janna; Both, Stephanie

2015-05-01

Emotion regulation research has shown successful altering of unwanted aversive emotional reactions. Cognitive strategies can also regulate expectations of reward arising from conditioned stimuli. However, less is known about the efficacy of such strategies with expectations elicited by conditioned appetitive sexual stimuli, and possible sex differences therein. In the present study it was examined whether a cognitive strategy (attentional deployment) could successfully down-regulate sexual arousal elicited by sexual reward-conditioned cues in men and women. A differential conditioning paradigm was applied, with genital vibrostimulation as unconditioned stimulus (US) and sexually relevant pictures as conditional stimuli (CSs). Evidence was found for emotion down-regulation to effect extinction of conditioned sexual responding in men. In women, the emotion down-regulatory strategy resulted in attenuated conditioned approach tendencies towards the CSs. The findings support that top-down modulation may indeed influence conditioned sexual responses. This knowledge may have implications for treating disturbances in sexual appetitive responses. Copyright © 2015. Published by Elsevier Ltd.

Retinoic Acid-inducible Gene I-inducible miR-23b Inhibits Infections by Minor Group Rhinoviruses through Down-regulation of the Very Low Density Lipoprotein Receptor*

PubMed Central

Ouda, Ryota; Onomoto, Koji; Takahasi, Kiyohiro; Edwards, Michael R.; Kato, Hiroki; Yoneyama, Mitsutoshi; Fujita, Takashi

2011-01-01

In mammals, viral infections are detected by innate immune receptors, including Toll-like receptor and retinoic acid inducible gene I (RIG-I)-like receptor (RLR), which activate the type I interferon (IFN) system. IFN essentially activates genes encoding antiviral proteins that inhibit various steps of viral replication as well as facilitate the subsequent activation of acquired immune responses. In this study, we investigated the expression of non-coding RNA upon viral infection or RLR activation. Using a microarray, we identified several microRNAs (miRNA) specifically induced to express by RLR signaling. As suggested by Bioinformatics (miRBase Target Data base), one of the RLR-inducible miRNAs, miR-23b, actually knocked down the expression of very low density lipoprotein receptor (VLDLR) and LDLR-related protein 5 (LRP5). Transfection of miR-23b specifically inhibited infection of rhinovirus 1B (RV1B), which utilizes the low density lipoprotein receptor (LDLR) family for viral entry. Conversely, introduction of anti-miRNA-23b enhanced the viral yield. Knockdown experiments using small interfering RNA (siRNA) revealed that VLDLR, but not LRP5, is critical for an efficient infection by RV1B. Furthermore, experiments with the transfection of infectious viral RNA revealed that miR-23b did not affect post-entry viral replication. Our results strongly suggest that RIG-I signaling results in the inhibitions of infections of RV1B through the miR-23b-mediated down-regulation of its receptor VLDLR. PMID:21642441

Retinoic acid-inducible gene I-inducible miR-23b inhibits infections by minor group rhinoviruses through down-regulation of the very low density lipoprotein receptor.

PubMed

Ouda, Ryota; Onomoto, Koji; Takahasi, Kiyohiro; Edwards, Michael R; Kato, Hiroki; Yoneyama, Mitsutoshi; Fujita, Takashi

2011-07-22

In mammals, viral infections are detected by innate immune receptors, including Toll-like receptor and retinoic acid inducible gene I (RIG-I)-like receptor (RLR), which activate the type I interferon (IFN) system. IFN essentially activates genes encoding antiviral proteins that inhibit various steps of viral replication as well as facilitate the subsequent activation of acquired immune responses. In this study, we investigated the expression of non-coding RNA upon viral infection or RLR activation. Using a microarray, we identified several microRNAs (miRNA) specifically induced to express by RLR signaling. As suggested by Bioinformatics (miRBase Target Data base), one of the RLR-inducible miRNAs, miR-23b, actually knocked down the expression of very low density lipoprotein receptor (VLDLR) and LDLR-related protein 5 (LRP5). Transfection of miR-23b specifically inhibited infection of rhinovirus 1B (RV1B), which utilizes the low density lipoprotein receptor (LDLR) family for viral entry. Conversely, introduction of anti-miRNA-23b enhanced the viral yield. Knockdown experiments using small interfering RNA (siRNA) revealed that VLDLR, but not LRP5, is critical for an efficient infection by RV1B. Furthermore, experiments with the transfection of infectious viral RNA revealed that miR-23b did not affect post-entry viral replication. Our results strongly suggest that RIG-I signaling results in the inhibitions of infections of RV1B through the miR-23b-mediated down-regulation of its receptor VLDLR.

High glucose induces formation of tau hyperphosphorylation via Cav-1-mTOR pathway: A potential molecular mechanism for diabetes-induced cognitive dysfunction

PubMed Central

Wu, Jing; Zhou, Shan-Lei; Pi, Lin-Hua; Shi, Xia-Jie; Ma, Ling-Ran; Chen, Zi; Qu, Min-Li; Li, Xin; Nie, Sheng-Dan; Liao, Duan-Fang; Pei, Jin-Jing; Wang, Shan

2017-01-01

The abnormally hyperphosphorylated tau is thought to be implicated in diabetes-associated cognitive deficits. The role of mammalian target of rapamycin (mTOR) / S6 kinase (S6K) signalling in the formation of tau hyperphosphorylation has been previously studied. Caveolin-1 (Cav-1), the essential structure protein of caveolae, promotes neuronal survival and growth, and inhibits glucose metabolism. In this study, we aimed to investigate the role of Cav-1 in the formation of tau hyperphosphorylation under chronic hyperglycemic condition (HGC). Diabetic rats were induced by streptozotocin (STZ). Primary hippocampal neurons with or without molecular intervention such as the transient over-expression or knock-down were subjected to HGC. The obtained experimental samples were analyzed by real time quantitative RT-PCR, Western blot, immunofluorescence or immunohistochemisty. We found: 1) that a chronic HGC directly decreases Cav-1 expression, increases tau phosphorylation and activates mTOR/S6K signalling in the brain neurons of diabetic rats, 2) that overexpression of Cav-1 attenuates tau hyperphosphorylation induced by chronic HGC in primary hippocampal neurons, whereas down-regulation of Cav-1 using Cav-1 siRNA dramatically worsens tau hyperphosphorylation via mTOR/S6K signalling pathway, and 3) that the down-regulation of Cav-1 induced by HGC is independent of mTOR signalling. Our results suggest that tau hyperphosphorylation and the sustained over-activated mTOR signalling under hyperglycemia may be due to the suppression of Cav-1. Therefore, Cav-1 is a potential therapeutic target for diabetes-induced cognitive dysfunction. PMID:28489581

Stress Conditions Promote Yeast Gap1 Permease Ubiquitylation and Down-regulation via the Arrestin-like Bul and Aly Proteins*

PubMed Central

Crapeau, Myriam; Merhi, Ahmad; André, Bruno

2014-01-01

Gap1, the yeast general amino acid permease, is a convenient model for studying how the intracellular traffic of membrane transporters is regulated. Present at the plasma membrane under poor nitrogen supply conditions, it undergoes ubiquitylation, endocytosis, and degradation upon activation of the TORC1 kinase complex in response to an increase in internal amino acids. This down-regulation is stimulated by TORC1-dependent phosphoinhibition of the Npr1 kinase, resulting in activation by dephosphorylation of the arrestin-like Bul1 and Bul2 adaptors recruiting the Rsp5 ubiquitin ligase to Gap1. We report here that Gap1 is also down-regulated when cells are treated with the TORC1 inhibitor rapamycin or subjected to various stresses and that a lack of the Tco89 subunit of TORC1 causes constitutive Gap1 down-regulation. Both the Bul1 and Bul2 and the Aly1 and Aly2 arrestin-like adaptors of Rsp5 promote this down-regulation without undergoing dephosphorylation. Furthermore, they act via the C-terminal regions of Gap1 not involved in ubiquitylation in response to internal amino acids, whereas a Gap1 mutant altered in the N-terminal tail and resistant to ubiquitylation by internal amino acids is efficiently down-regulated under stress via the Bul and Aly adaptors. Although the Bul proteins mediate Gap1 ubiquitylation of two possible lysines, Lys-9 and Lys-16, the Aly proteins promote ubiquitylation of the Lys-16 residue only. This stress-induced pathway of Gap1 down-regulation targets other permeases as well, and it likely allows cells facing adverse conditions to retrieve amino acids from permease degradation. PMID:24942738

Drp1 guarding of the mitochondrial network is important for glucose-stimulated insulin secretion in pancreatic beta cells

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

Reinhardt, Florian; Schultz, Julia; Waterstradt, Rica

Mitochondria form a tubular network in mammalian cells, and the mitochondrial life cycle is determined by fission, fusion and autophagy. Dynamin-related protein 1 (Drp1) has a pivotal role in these processes because it alone is able to constrict mitochondria. However, the regulation and function of Drp1 have been shown to vary between cell types. Mitochondrial morphology affects mitochondrial metabolism and function. In pancreatic beta cells mitochondrial metabolism is a key component of the glucose-induced cascade of insulin secretion. The goal of the present study was to investigate the action of Drp1 in pancreatic beta cells. For this purpose Drp1 wasmore » down-regulated by means of shDrp1 in insulin-secreting INS1 cells and mouse pancreatic islets. In INS1 cells reduced Drp1 expression resulted in diminished expression of proteins regulating mitochondrial fusion, namely mitofusin 1 and 2, and optic atrophy protein 1. Diminished mitochondrial dynamics can therefore be assumed. After down-regulation of Drp1 in INS1 cells and spread mouse islets the initially homogenous mitochondrial network characterised by a moderate level of interconnections shifted towards high heterogeneity with elongated, clustered and looped mitochondria. These morphological changes were found to correlate directly with functional alterations. Mitochondrial membrane potential and ATP generation were significantly reduced in INS1 cells after Drp1down-regulation. Finally, a significant loss of glucose-stimulated insulin secretion was demonstrated in INS1 cells and mouse pancreatic islets. In conclusion, Drp1 expression is important in pancreatic beta cells to maintain the regulation of insulin secretion. -- Highlights: •Down-regulation of Drp1 in INS1 cells reduces mitochondrial fusion protein expression. •Mitochondrial membrane potential in INS1 cells is diminished after Drp1 down-regulation. •Mitochondria become elongated after down-regulation of Drp1 in beta cells. •Down-regulation of Drp1 in islets evokes loss of glucose-stimulated insulin secretion.« less

15-Deoxy-{delta}{sup 12,14}-prostaglandin J{sub 2} down-regulates CXCR4 on carcinoma cells through PPAR{gamma}- and NF{kappa}B-mediated pathways

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

Richard, Cynthia Lee; Lowthers, Erica Lauren; Blay, Jonathan

2007-10-01

The chemokine receptor CXCR4 plays a key role in the metastasis of colorectal cancer and its growth at metastatic sites. Here, we have investigated the mechanisms by which CXCR4 on cancer cells might be regulated by eicosanoids present within the colorectal tumor microenvironment. We show that prostaglandins PGE{sub 2}, PGA{sub 2}, PGD{sub 2}, PGJ{sub 2} and 15dPGJ{sub 2} each down-regulates CXCR4 receptor expression on human colorectal carcinoma cells to differing degrees. The most potent of these were PGD{sub 2} and its metabolites PGJ{sub 2} and 15dPGJ{sub 2}. Down-regulation was most rapid with the end-product 15dPGJ{sub 2} and was accompanied bymore » a marked reduction in CXCR4 mRNA. 15dPGJ{sub 2} is known to be a ligand for the nuclear receptor PPAR{gamma}. Down-regulation of CXCR4 was also observed with the PPAR{gamma} agonist rosiglitazone, while 15dPGJ{sub 2}-induced CXCR4 down-regulation was substantially diminished by the PPAR{gamma} antagonists GW9662 and T0070907. These data support the involvement of PPAR{gamma}. However, the 15dPGJ{sub 2} analogue CAY10410, which can act on PPAR{gamma} but which lacks the intrinsic cyclopentenone structure found in 15dPGJ{sub 2}, down-regulated CXCR4 substantially less potently than 15dPGJ{sub 2}. The cyclopentenone grouping is known to inhibit the activity of NF{kappa}B. Consistent with an additional role for NF{kappa}B, we found that the cyclopentenone prostaglandin PGA{sub 2} and cyclopentenone itself could also down-regulate CXCR4. Immunolocalization studies showed that the cellular context was sufficient to trigger a focal nuclear pattern of NF{kappa}B p50 and that 15dPGJ{sub 2} interfered with this p50 nuclear localization. These data suggest that 15dPGJ{sub 2} can down-regulate CXCR4 on cancer cells through both PPAR{gamma} and NF{kappa}B. 15dPGJ{sub 2}, present within the tumor microenvironment, may act to down-regulate CXCR4 and impact upon the overall process of tumor expansion.« less

Down-regulation of gibberellic acid in poplar has negligible effects on host-plant suitability and insect pest response

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

Buhl, Christine; Strauss, Steven H.; Lindroth, Richard L.

Abstract Endogenous levels and signaling of gibberellin plant hormones such as gibberellic acid (GA) have been genetically down-regulated to create semi-dwarf varieties of poplar. The potential benefits of semi-dwarf stature include reduced risk of wind damage, improved stress tolerance, and improved wood quality. Despite these benefits, modification of growth traits may have consequences for non-target traits that confer defense against insect herbivores. According to the growth-differentiation balance hypothesis, reductions in growth may shift allocation of carbon from growth to chemical resistance traits, thereby altering plant defense. To date, host-plant suitability and pest response have not been comprehensively evaluated in GAmore » down-regulated plants. We quantified chemical resistance and nitrogen (an index of protein) in GA down-regulated and wild-type poplar (Populus alba × P. tremula) genotypes. We also evaluated performance of both generalist (Lymantria dispar) and specialist (Chrysomela scripta) insect pests reared on these genotypes. Our evaluation of resistance traits in four GA down-regulated genotypes revealed increased phenolic glycosides in one modified genotype and reduced lignin in two modified genotypes relative to the non-transgenic wild type. Nitrogen levels did not vary significantly among the experimental genotypes. Generalists reared on the four GA down-regulated genotypes exhibited reduced performance on only one modified genotype relative to the wild type. Specialists, however, performed similarly across all genotypes. Results from this study indicate that although some non-target traits varied among GA down-regulated genotypes, the differences in poplar pest susceptibility were modest and highly genotype-specific.« less

Down-regulation of gibberellic acid in poplar has negligible effects on host-plant suitability and insect pest response

DOE PAGES

Buhl, Christine; Strauss, Steven H.; Lindroth, Richard L.

2015-01-06

Abstract Endogenous levels and signaling of gibberellin plant hormones such as gibberellic acid (GA) have been genetically down-regulated to create semi-dwarf varieties of poplar. The potential benefits of semi-dwarf stature include reduced risk of wind damage, improved stress tolerance, and improved wood quality. Despite these benefits, modification of growth traits may have consequences for non-target traits that confer defense against insect herbivores. According to the growth-differentiation balance hypothesis, reductions in growth may shift allocation of carbon from growth to chemical resistance traits, thereby altering plant defense. To date, host-plant suitability and pest response have not been comprehensively evaluated in GAmore » down-regulated plants. We quantified chemical resistance and nitrogen (an index of protein) in GA down-regulated and wild-type poplar (Populus alba × P. tremula) genotypes. We also evaluated performance of both generalist (Lymantria dispar) and specialist (Chrysomela scripta) insect pests reared on these genotypes. Our evaluation of resistance traits in four GA down-regulated genotypes revealed increased phenolic glycosides in one modified genotype and reduced lignin in two modified genotypes relative to the non-transgenic wild type. Nitrogen levels did not vary significantly among the experimental genotypes. Generalists reared on the four GA down-regulated genotypes exhibited reduced performance on only one modified genotype relative to the wild type. Specialists, however, performed similarly across all genotypes. Results from this study indicate that although some non-target traits varied among GA down-regulated genotypes, the differences in poplar pest susceptibility were modest and highly genotype-specific.« less

An N-terminal fragment of substance P, substance P(1-7), down-regulates neurokinin-1 binding in the mouse spinal cord.

PubMed

Yukhananov RYu; Larson, A A

1994-08-29

Injected intrathecally, substance P (SP) down-regulates neurokinin-1 (NK-1) binding in the spinal cord and desensitizes rats to the behavioral effect of SP. N-terminal fragments of SP, such as SP(1-7), induce antinociception and play a role in desensitization to SP in mice. The goal of this study was to assess the abilities of N- and C-terminal fragments of SP to down-regulate NK-1 binding. Binding of [3H]SP to mouse spinal cord membranes was inhibited by SP, CP-96,345, and to a lesser extent by SP(5-11), but not SP(1-7), consistent with these binding sites being NK-1 receptors. Injection of SP(5-11) intrathecally did not affect the affinity (Kd) or concentration (Bmax) of [3H]SP binding. However, injection of 1 nmol of SP(1-7) decreased the Bmax of [3H]SP binding in the spinal cord at 6 h after its injection just as this dose of SP decreased the Bmax at 24 h. These data suggest that the N-terminus of SP is responsible for down-regulation of NK-1 binding. As SP(5-11) did not down-regulate NK-1 binding, activation of NK-1 sites does not appear necessary or sufficient for down-regulation of SP binding. In contrast, SP(1-7), in spite of its inability to interact with NK-1 sites, did down-regulate SP binding, suggesting an indirect mechanism dissociated from NK-1 receptors.

Species-Independent Down-Regulation of Leaf Photosynthesis and Respiration in Response to Shading: Evidence from Six Temperate Tree Species

PubMed Central

Chen, Anping; Lichstein, Jeremy W.; Osnas, Jeanne L. D.; Pacala, Stephen W.

2014-01-01

The ability to down-regulate leaf maximum net photosynthetic capacity (Amax) and dark respiration rate (Rdark) in response to shading is thought to be an important adaptation of trees to the wide range of light environments that they are exposed to across space and time. A simple, general rule that accurately described this down-regulation would improve carbon cycle models and enhance our understanding of how forest successional diversity is maintained. In this paper, we investigated the light response of Amax and Rdark for saplings of six temperate forest tree species in New Jersey, USA, and formulated a simple model of down-regulation that could be incorporated into carbon cycle models. We found that full-sun values of Amax and Rdark differed significantly among species, but the rate of down-regulation (proportional decrease in Amax or Rdark relative to the full-sun value) in response to shade was not significantly species- or taxon-specific. Shade leaves of sun-grown plants appear to follow the same pattern of down-regulation in response to shade as leaves of shade-grown plants. Given the light level above a leaf and one species-specific number (either the full-sun Amax or full-sun Rdark), we provide a formula that can accurately predict the leaf's Amax and Rdark. We further show that most of the down regulation of per unit area Rdark and Amax is caused by reductions in leaf mass per unit area (LMA): as light decreases, leaves get thinner, while per unit mass Amax and Rdark remain approximately constant. PMID:24727745

Down-regulation of Transducin-Like Enhancer of Split protein 4 in hepatocellular carcinoma promotes cell proliferation and epithelial-Mesenchymal-Transition

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

Wu, Xiao-cai; Xiao, Cui-cui; Li, Hua

Background: Transducin-Like Enhancer of Split protein 4 (TLE4) has been reported to be involved in some subsets of acute myeloid leukemia and colorectal cancer. In the present study, we aimed to explore the role of TLE4 in tumorigenesis and cancer progression in hepatocellular carcinoma (HCC). Methods: The expression pattern of TLE4 in HCC was determined by Western-blot and qRT-PCR, gain-of-function and loss-of-function was used to explore the biological role of TLE4 in HCC cells. A xenograft model was established to confirm its effects on proliferation. Results: The protein expression levels of TLE4 were significantly down-regulated in HCC tissues compared tomore » matched adjacent normal liver tissues. In vitro, down-regulation of TLE4 in Huh7 or SMMC-7721 promoted cell proliferation and ectopical expression of TLE4 in Hep3B or Bel-7404 suppressed cell proliferation. In addition, the cell colony formation ability was enhanced after down-regulation of TLE4 expression in Huh-7 but suppressed after over-expression in Hep3B. Furthermore, down-regulation of TLE4 increased the cell invasion ability, as well as increased the expression level of Vimentin and decreased that of E-cadherin, indicating a phenotype of epithelial-mesenchymal transition (EMT) in HCC cells. On the contrary, ectopical expression of TLE4 in HCC cells decreased the cell invasion ability and inhibited EMT. In vivo, compared to control group, xenograft tumor volumes were significantly decreased in TLE4 overexpression group. Conclusions: These results demonstrated that TLE4 might play important regulatory roles in cellular proliferation and EMT process in HCC. - Highlights: • TLE4 is significantly down-regulated in HCC samples. • Down regulated of TLE4 in HCC cells promotes cell proliferation. • Down regulated of TLE4 in HCC cells promotes epithelial-to-mesenchymal transition.« less

Down-regulation of MutS homolog 3 by hypoxia in human colorectal cancer

PubMed Central

Li, Jie; Koike, Junichi; Kugoh, Hiroyuki; Arita, Michitsune; Ohhira, Takahito; Kikuchi, Yoshinori; Funahashi, Kimihiko; Takamatsu, Ken; Boland, C. Richard; Koi, Minoru; Hemmi, Hiromichi

2013-01-01

Down-regulation of hMSH3 is associated with elevated microsatellite alterations at selected tetranucleotide repeats and low levels of microsatellite instability in colorectal cancer (CRC). However, the mechanism that down-regulates hMSH3 in CRC is not known. In this study, a significant association between over-expression of glucose transporter 1, a marker for hypoxia, and down-regulation of hMSH3 in CRC tissues was observed. Therefore, we examined the effect of hypoxia on the expression of hMSH3 in human cell lines. When cells with wild type p53 (wt-p53) were exposed to hypoxia, rapid down-regulation of both hMSH2 and hMSH3 occurred. In contrast, when null or mutated p53 (null/mut-p53) cells were exposed to hypoxia, only hMSH3 was down-regulated, and at slower rate than wt-p53 cells. Using a reporter assay, we found that disruption of the two putative hypoxia response elements (HREs) located within the promoter region of the hMSH3 abrogated the suppressive effect of hypoxia on reporter activity regardless of p53 status. In an EMSA, two different forms of HIF-1α complexes that specifically bind to these HREs were detected. A larger complex containing HIF-1α predominantly bound to the HREs in hypoxic null/mut-p53 cells whereas a smaller complex predominated in wt-p53 cells. Finally, HIF-1α knockdown by siRNA significantly inhibited down-regulation of hMSH3 by hypoxia in both wt-p53 and mut-p53 cells. Taken together, our results suggest that the binding of HIF-1α complexes to HRE sites is necessary for down-regulation of hMSH3 in both wt-p53 and mut-p53 cells. PMID:22343000

Twilight, a Novel Circadian-Regulated Gene, Integrates Phototropism with Nutrient and Redox Homeostasis during Fungal Development

PubMed Central

Naqvi, Naweed I.

2015-01-01

Phototropic regulation of circadian clock is important for environmental adaptation, organismal growth and differentiation. Light plays a critical role in fungal development and virulence. However, it is unclear what governs the intracellular metabolic response to such dark-light rhythms in fungi. Here, we describe a novel circadian-regulated Twilight (TWL) function essential for phototropic induction of asexual development and pathogenesis in the rice-blast fungus Magnaporthe oryzae. The TWL transcript oscillates during circadian cycles and peaks at subjective twilight. GFP-Twl remains acetylated and cytosolic in the dark, whereas light-induced phosphorylation (by the carbon sensor Snf1 kinase) drives it into the nucleus. The mRNA level of the transcription/repair factor TFB5, was significantly down regulated in the twl∆ mutant. Overexpression of TFB5 significantly suppressed the conidiation defects in the twl∆ mutant. Furthermore, Tfb5-GFP translocates to the nucleus during the phototropic response and under redox stress, while it failed to do so in the twl∆ mutant. Thus, we provide mechanistic insight into Twl-based regulation of nutrient and redox homeostasis in response to light during pathogen adaptation to the host milieu in the rice blast pathosystem. PMID:26102503

Twilight, a Novel Circadian-Regulated Gene, Integrates Phototropism with Nutrient and Redox Homeostasis during Fungal Development.

PubMed

Deng, Yi Zhen; Qu, Ziwei; Naqvi, Naweed I

2015-06-01

Phototropic regulation of circadian clock is important for environmental adaptation, organismal growth and differentiation. Light plays a critical role in fungal development and virulence. However, it is unclear what governs the intracellular metabolic response to such dark-light rhythms in fungi. Here, we describe a novel circadian-regulated Twilight (TWL) function essential for phototropic induction of asexual development and pathogenesis in the rice-blast fungus Magnaporthe oryzae. The TWL transcript oscillates during circadian cycles and peaks at subjective twilight. GFP-Twl remains acetylated and cytosolic in the dark, whereas light-induced phosphorylation (by the carbon sensor Snf1 kinase) drives it into the nucleus. The mRNA level of the transcription/repair factor TFB5, was significantly down regulated in the twl∆ mutant. Overexpression of TFB5 significantly suppressed the conidiation defects in the twl∆ mutant. Furthermore, Tfb5-GFP translocates to the nucleus during the phototropic response and under redox stress, while it failed to do so in the twl∆ mutant. Thus, we provide mechanistic insight into Twl-based regulation of nutrient and redox homeostasis in response to light during pathogen adaptation to the host milieu in the rice blast pathosystem.

Protein kinase C β inhibits autophagy and sensitizes cervical cancer Hela cells to cisplatin.

PubMed

Li, Na; Zhang, Wei

2017-04-28

Recently, autophagy has been indicated to play an essential role in various biological events, such as the response of cervical cancer cells to chemotherapy. However, the exact signalling mechanism that regulates autophagy during chemotherapy remains unclear. In the present study, we investigated the regulation by cisplatin on protein kinase C β (PKC β), on B-cell lymphoma 2 (Bcl-2) and on apoptosis in cervical cancer Hela cells. And then we examined the regulation by cisplatin on autophagy and the role of autophagy on the chemotherapy in Hela cells. In addition, the regulation of the PKC β on the autophagy was also investigated. Our results indicated that cisplatin promoted PKC β in Hela cells. The PKC β inhibitor reduced the cisplatin-induced apoptosis, whereas increased the cisplatin-induced autophagy in Hela cells. On the other side, the PKC β overexpression aggravated the cisplatin-induced apoptosis, whereas down-regulated the cisplatin-induced autophagy. Taken together, our study firstly recognized the involvement of PKC β in the cytotoxicity of cisplatin via inhibiting autophagy in cervical cancer cells. We propose that PKC β would sensitize cervical cancer cells to chemotherapy via reducing the chemotherapy induced autophagy in cancer cells. © 2017 The Author(s).

MASTR directs MyoD-dependent satellite cell differentiation during skeletal muscle regeneration

PubMed Central

Mokalled, Mayssa H.; Johnson, Aaron N.; Creemers, Esther E.; Olson, Eric N.

2012-01-01

In response to skeletal muscle injury, satellite cells, which function as a myogenic stem cell population, become activated, expand through proliferation, and ultimately fuse with each other and with damaged myofibers to promote muscle regeneration. Here, we show that members of the Myocardin family of transcriptional coactivators, MASTR and MRTF-A, are up-regulated in satellite cells in response to skeletal muscle injury and muscular dystrophy. Global and satellite cell-specific deletion of MASTR in mice impairs skeletal muscle regeneration. This impairment is substantially greater when MRTF-A is also deleted and is due to aberrant differentiation and excessive proliferation of satellite cells. These abnormalities mimic those associated with genetic deletion of MyoD, a master regulator of myogenesis, which is down-regulated in the absence of MASTR and MRTF-A. Consistent with an essential role of MASTR in transcriptional regulation of MyoD expression, MASTR activates a muscle-specific postnatal MyoD enhancer through associations with MEF2 and members of the Myocardin family. Our results provide new insights into the genetic circuitry of muscle regeneration and identify MASTR as a central regulator of this process. PMID:22279050

Bottom-up and top-down emotion generation: implications for emotion regulation

PubMed Central

Misra, Supriya; Prasad, Aditya K.; Pereira, Sean C.; Gross, James J.

2012-01-01

Emotion regulation plays a crucial role in adaptive functioning and mounting evidence suggests that some emotion regulation strategies are often more effective than others. However, little attention has been paid to the different ways emotions can be generated: from the ‘bottom-up’ (in response to inherently emotional perceptual properties of the stimulus) or ‘top-down’ (in response to cognitive evaluations). Based on a process priming principle, we hypothesized that mode of emotion generation would interact with subsequent emotion regulation. Specifically, we predicted that top-down emotions would be more successfully regulated by a top-down regulation strategy than bottom-up emotions. To test this hypothesis, we induced bottom-up and top-down emotions, and asked participants to decrease the negative impact of these emotions using cognitive reappraisal. We observed the predicted interaction between generation and regulation in two measures of emotional responding. As measured by self-reported affect, cognitive reappraisal was more successful on top-down generated emotions than bottom-up generated emotions. Neurally, reappraisal of bottom-up generated emotions resulted in a paradoxical increase of amygdala activity. This interaction between mode of emotion generation and subsequent regulation should be taken into account when comparing of the efficacy of different types of emotion regulation, as well as when reappraisal is used to treat different types of clinical disorders. PMID:21296865

α-Phellandrene alters expression of genes associated with DNA damage, cell cycle, and apoptosis in murine leukemia WEHI-3 cells.

PubMed

Lin, Jen-Jyh; Yu, Chien-Chih; Lu, Kung-Wen; Chang, Shu-Jen; Yu, Fu-Shun; Liao, Ching-Lung; Lin, Jaung-Geng; Chung, Jing-Gung

2014-08-01

α-phellandrene (α-PA) is a cyclic monoterpene, present in natural plants such as Schinus molle L. α-PA promotes immune responses in mice in vivo. However, there is no available information on whether α-PA affects gene expression in leukemia cells. The present study determined effects of α-PA on expression levels of genes associated with DNA damage, cell cycle and apoptotic cell death in mouse leukemia WEHI-3 cells. WEHI-3 cells were treated with 10 μM α-PA for 24 h, cells were harvested and total RNA was extracted, and gene expression was analyzed by cDNA microarray. Results indicated that α-PA up-regulated 10 genes 4-fold, 13 by over 3-fold and 175 by over 2-fold; 21 genes were down-regulated by over 4-fold, 26 genes by over 3-fold and expression of 204 genes was altered by at leas 2-fold compared with the untreated control cells. DNA damage-associated genes such as DNA damage-inducer transcript 4 and DNA fragmentation factor were up-regulated by 4-fold and over 2-fold, respectively; cell-cycle check point genes such as cyclin G2 and cyclin-dependent kinases inhibitor 2D and IA (p21) were up-regulated by over 3-fold and over 2-fold, respectively; apoptosis-associated genes such as BCL2/adenovirus EIB interacting protein 3, XIAP-associated factor 1, BCL2 modifying factor, caspase-8 and FADD-like apoptosis regulator were over 2-fold up-regulated. Furthermore, DNA damage-associated gene TATA box binding protein was over 4-fold down-regulated, and D19Ertd652c (DNA segment) over 2-fold down-regulated; cell cycle-associated gene cyclin E2 was over 2-fold down-regulated; apoptosis associated gene growth arrest-specific 5 was over 9-fold down-regulated, Gm5426 (ATP synthase) was over 3-fold down-regulated, and death box polypeptide 33 was over 2-fold down-regulated. Based on these observations, α-PA altered gene expression in WEHI-3 cells in vitro. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

DNA stress and strain, in silico, in vitro and in vivo

NASA Astrophysics Data System (ADS)

Levens, David; Benham, Craig J.

2011-06-01

A vast literature has explored the genetic interactions among the cellular components regulating gene expression in many organisms. Early on, in the absence of any biochemical definition, regulatory modules were conceived using the strict formalism of genetics to designate the modifiers of phenotype as either cis- or trans-acting depending on whether the relevant genes were embedded in the same or separate DNA molecules. This formalism distilled gene regulation down to its essence in much the same way that consideration of an ideal gas reveals essential thermodynamic and kinetic principles. Yet just as the anomalous behavior of materials may thwart an engineer who ignores their non-ideal properties, schemes to control and manipulate the genetic and epigenetic programs of cells may falter without a fuller and more quantitative elucidation of the physical and chemical characteristics of DNA and chromatin in vivo.

Deletion of Interleukin-6 Signal Transducer gp130 in Small Sensory Neurons Attenuates Mechanonociception and Down-Regulates TRPA1 Expression

PubMed Central

Malsch, Philipp; Andratsch, Manfred; Vogl, Christian; Link, Andrea S.; Alzheimer, Christian; Brierley, Stuart M.; Hughes, Patrick A.

2014-01-01

Glycoprotein 130 (gp130) is the signal transducing receptor subunit for cytokines of the interleukin-6 (IL-6) family, and it is expressed in a multitude of cell types of the immune and nervous system. IL-6-like cytokines are not only key regulators of innate immunity and inflammation but are also essential factors for the differentiation and development of the somatosensory system. Mice with a null mutation of gp130 in primary nociceptive afferents (SNS-gp130−/−) are largely protected from hypersensitivity to mechanical stimuli in mouse models of pathological pain. Therefore, we set out to investigate how neuronal gp130 regulates mechanonociception. SNS-gp130−/− mice revealed reduced mechanosensitivity to high mechanical forces in the von Frey assay in vivo, and this was associated with a reduced sensitivity of nociceptive primary afferents in vitro. Together with these findings, transient receptor potential ankyrin 1 (TRPA1) mRNA expression was significantly reduced in DRG from SNS-gp130−/− mice. This was also reflected by a reduced number of neurons responding with calcium transients to TRPA1 agonists in primary DRG cultures. Downregulation of Trpa1 expression was predominantly discovered in nonpeptidergic neurons, with the deficit becoming evident during stages of early postnatal development. Regulation of Trpa1 mRNA expression levels downstream of gp130 involved the classical Janus kinase family-signal transducer and activator of transcription pathway. Our results closely link proinflammatory cytokines to the expression of TRPA1, both of which have been shown to contribute to hypersensitive pain states. We suggest that gp130 has an essential role in mechanonociception and in the regulation of TRPA1 expression. PMID:25057188

Multiple myeloma on polycythemia vera following radioactive phosphorus therapy

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

West, W.O.

1976-11-01

A 74-year-old white man with established polycythemia vera was treated with radioactive phosphorus after phlebotomies alone failed to control his disease. About 2/sup 3///sub 4/ years later he died of multiple myeloma. The mutagenic effect of radioactive phosphorus may have caused or possibly accelerated preexisting myeloma. Basic nonmalignant disease deserves careful consideration before radiation or radiomimetic agents are used. One might consider a probably less mutagenic drug such as hydroxyurea in patients with polycythemia vera when phlebotomy alone does not give good control of red cell mass and thrombocytosis.

Relationships between self-regulation and personality scores of persons with Down syndrome.

PubMed

Kojima, M; Ikeda, Y

2001-12-01

This study examined the associations of self-regulation (scores on self-assertion and self control) with personality traits for 76 persons with Down syndrome. Analysis shows self-assertion scores were correlated with scores for all personality traits. The correlations were significant with Emotionality and Playfulness for people with Down syndrome but not for those without Down syndrome (n=40). Self-control scores significantly correlated with scores on controlling and attachment for both groups. Emotionality was related to scores on self-control for students without Down syndrome but not for those with Down syndrome.

A High Phosphorus Diet Affects Lipid Metabolism in Rat Liver: A DNA Microarray Analysis

PubMed Central

Chun, Sunwoo; Bamba, Takeshi; Suyama, Tatsuya; Ishijima, Tomoko; Fukusaki, Eiichiro; Abe, Keiko; Nakai, Yuji

2016-01-01

A high phosphorus (HP) diet causes disorders of renal function, bone metabolism, and vascular function. We previously demonstrated that DNA microarray analysis is an appropriate method to comprehensively evaluate the effects of a HP diet on kidney dysfunction such as calcification, fibrillization, and inflammation. We reported that type IIb sodium-dependent phosphate transporter is significantly up-regulated in this context. In the present study, we performed DNA microarray analysis to investigate the effects of a HP diet on the liver, which plays a pivotal role in energy metabolism. DNA microarray analysis was performed with total RNA isolated from the livers of rats fed a control diet (containing 0.3% phosphorus) or a HP diet (containing 1.2% phosphorus). Gene Ontology analysis of differentially expressed genes (DEGs) revealed that the HP diet induced down-regulation of genes involved in hepatic amino acid catabolism and lipogenesis, while genes related to fatty acid β-oxidation process were up-regulated. Although genes related to fatty acid biosynthesis were down-regulated in HP diet-fed rats, genes important for the elongation and desaturation reactions of omega-3 and -6 fatty acids were up-regulated. Concentrations of hepatic arachidonic acid and eicosapentaenoic acid were increased in HP diet-fed rats. These essential fatty acids activate peroxisome proliferator-activated receptor alpha (PPARα), a transcription factor for fatty acid β-oxidation. Evaluation of the upstream regulators of DEGs using Ingenuity Pathway Analysis indicated that PPARα was activated in the livers of HP diet-fed rats. Furthermore, the serum concentration of fibroblast growth factor 21, a hormone secreted from the liver that promotes fatty acid utilization in adipose tissue as a PPARα target gene, was higher (p = 0.054) in HP diet-fed rats than in control diet-fed rats. These data suggest that a HP diet enhances energy expenditure through the utilization of free fatty acids released via lipolysis of white adipose tissue. PMID:27187182

Lysine and Leucine Deficiencies Affect Myocytes Development and IGF Signaling in Gilthead Sea Bream (Sparus aurata)

PubMed Central

Azizi, Sheida; Nematollahi, Mohammad Ali; Mojazi Amiri, Bagher; Vélez, Emilio J.; Lutfi, Esmail; Navarro, Isabel; Capilla, Encarnación; Gutiérrez, Joaquim

2016-01-01

Optimizing aquaculture production requires better knowledge of growth regulation and improvement in diet formulation. A great effort has been made to replace fish meal for plant protein sources in aquafeeds, making necessary the supplementation of such diets with crystalline amino acids (AA) to cover the nutritional requirements of each species. Lysine and Leucine are limiting essential AA in fish, and it has been demonstrated that supplementation with them improves growth in different species. However, the specific effects of AA deficiencies in myogenesis are completely unknown and have only been studied at the level of hepatic metabolism. It is well-known that the TOR pathway integrates the nutritional and hormonal signals to regulate protein synthesis and cell proliferation, to finally control muscle growth, a process also coordinated by the expression of myogenic regulatory factors (MRFs). This study aimed to provide new information on the impact of Lysine and Leucine deficiencies in gilthead sea bream cultured myocytes examining their development and the response of insulin-like growth factors (IGFs), MRFs, as well as key molecules involved in muscle growth regulation like TOR. Leucine deficiency did not cause significant differences in most of the molecules analyzed, whereas Lysine deficiency appeared crucial in IGFs regulation, decreasing significantly IGF-I, IGF-II and IGF-IRb mRNA levels. This treatment also down-regulated the gene expression of different MRFs, including Myf5, Myogenin and MyoD2. These changes were also corroborated by a significant decrease in proliferation and differentiation markers in the Lysine-deficient treatment. Moreover, both Lysine and Leucine limitation induced a significant down-regulation in FOXO3 gene expression, which deserves further investigation. We believe that these results will be relevant for the production of a species as appreciated for human consumption as it is gilthead sea bream and demonstrates the importance of an adequate level of Lysine in fishmeal diet formulation for optimum growth. PMID:26808650

29 CFR Appendix to Subpart E of... - Exit Routes, Emergency Action Plans, and Fire Prevention Plans

Code of Federal Regulations, 2012 CFR

2012-07-01

... selected to remain behind to care for essential plant operations until their evacuation becomes absolutely necessary. Essential plant operations may include the monitoring of plant power supplies, water supplies, and other essential services which cannot be shut down for every emergency alarm. Essential plant...

29 CFR Appendix to Subpart E of... - Exit Routes, Emergency Action Plans, and Fire Prevention Plans

Code of Federal Regulations, 2014 CFR

2014-07-01

... selected to remain behind to care for essential plant operations until their evacuation becomes absolutely necessary. Essential plant operations may include the monitoring of plant power supplies, water supplies, and other essential services which cannot be shut down for every emergency alarm. Essential plant...

29 CFR Appendix to Subpart E of... - Exit Routes, Emergency Action Plans, and Fire Prevention Plans

Code of Federal Regulations, 2011 CFR

2011-07-01

... selected to remain behind to care for essential plant operations until their evacuation becomes absolutely necessary. Essential plant operations may include the monitoring of plant power supplies, water supplies, and other essential services which cannot be shut down for every emergency alarm. Essential plant...

29 CFR Appendix to Subpart E of... - Exit Routes, Emergency Action Plans, and Fire Prevention Plans

Code of Federal Regulations, 2013 CFR

2013-07-01

... selected to remain behind to care for essential plant operations until their evacuation becomes absolutely necessary. Essential plant operations may include the monitoring of plant power supplies, water supplies, and other essential services which cannot be shut down for every emergency alarm. Essential plant...

Optimal Down Regulation of mRNA Translation

NASA Astrophysics Data System (ADS)

Zarai, Yoram; Margaliot, Michael; Tuller, Tamir

2017-01-01

Down regulation of mRNA translation is an important problem in various bio-medical domains ranging from developing effective medicines for tumors and for viral diseases to developing attenuated virus strains that can be used for vaccination. Here, we study the problem of down regulation of mRNA translation using a mathematical model called the ribosome flow model (RFM). In the RFM, the mRNA molecule is modeled as a chain of n sites. The flow of ribosomes between consecutive sites is regulated by n + 1 transition rates. Given a set of feasible transition rates, that models the outcome of all possible mutations, we consider the problem of maximally down regulating protein production by altering the rates within this set of feasible rates. Under certain conditions on the feasible set, we show that an optimal solution can be determined efficiently. We also rigorously analyze two special cases of the down regulation optimization problem. Our results suggest that one must focus on the position along the mRNA molecule where the transition rate has the strongest effect on the protein production rate. However, this rate is not necessarily the slowest transition rate along the mRNA molecule. We discuss some of the biological implications of these results.

Ufmylation and FATylation Pathways are Down Regulated in Human Alcoholic and Non Alcoholic Steatohepatitis, and Mice Fed DDC, where Mallory-Denk Bodies (MDBs) Form

PubMed Central

Liu, H; Li, J; Tillman, B; French, BA; French, SW

2014-01-01

We previously reported the mechanisms involved in the formation of Mallory-Denk bodies (MDBs) in mice fed DDC. To further provide clinical evidence as to how ubiquitin-like protein (Ubls) modification, gene transcript expression in Ufmylation and FATylation were investigated in human archived formalin-fixed, paraffin-embedded (FFPE) liver biopsies and frozen liver sections from DDC re-fed mice were used. Real-time PCR analysis showed that all Ufmylation molecules (Ufm1, Uba5, Ufc1, Ufl1 and UfSPs) were significantly down regulated, both in DDC re-fed mice livers and patients’ livers where MDBs had formed, indicating that gene transcript changes were limited to MDB-forming livers where the protein quality control system was down regulated. FAT10 and subunits of the immunoproteasome (LMP2 and LMP7) were both up regulated as previously shown. An approximate 176- and 5-fold up regulation (respectively) of FAT10 were observed in the DDC re-fed mice liver and in the livers of human alcoholic hepatitis with MDBs present, implying that there was an important role played by this gene. The FAT10-specific E1 and E2 enzymes Uba6 and USE1, however, were found to be down regulated both in patients’ livers and in the liver of DDC re-fed mice. Interestedly, the down regulation of mRNA levels was proportionate to MDB abundance in the liver tissues. Our results show the first systematic demonstration of transcript regulation of Ufmylation and FATylation in the liver of patients who form MDBs, where protein quality control is down regulated. This was also shown in livers of DDC re-fed mice where MDBs had formed. PMID:24893112

HIF and HOIL-1L-mediated PKCζ degradation stabilizes plasma membrane Na,K-ATPase to protect against hypoxia-induced lung injury.

PubMed

Magnani, Natalia D; Dada, Laura A; Queisser, Markus A; Brazee, Patricia L; Welch, Lynn C; Anekalla, Kishore R; Zhou, Guofei; Vagin, Olga; Misharin, Alexander V; Budinger, G R Scott; Iwai, Kazuhiro; Ciechanover, Aaron J; Sznajder, Jacob I

2017-11-21

Organisms have evolved adaptive mechanisms in response to stress for cellular survival. During acute hypoxic stress, cells down-regulate energy-consuming enzymes such as Na,K-ATPase. Within minutes of alveolar epithelial cell (AEC) exposure to hypoxia, protein kinase C zeta (PKCζ) phosphorylates the α 1 -Na,K-ATPase subunit and triggers it for endocytosis, independently of the hypoxia-inducible factor (HIF). However, the Na,K-ATPase activity is essential for cell homeostasis. HIF induces the heme-oxidized IRP2 ubiquitin ligase 1L (HOIL-1L), which leads to PKCζ degradation. Here we report a mechanism of prosurvival adaptation of AECs to prolonged hypoxia where PKCζ degradation allows plasma membrane Na,K-ATPase stabilization at ∼50% of normoxic levels, preventing its excessive down-regulation and cell death. Mice lacking HOIL-1L in lung epithelial cells ( Cre SPC /HOIL-1L fl/fl ) were sensitized to hypoxia because they express higher levels of PKCζ and, consequently, lower plasma membrane Na,K-ATPase levels, which increased cell death and worsened lung injury. In AECs, expression of an α 1 -Na,K-ATPase construct bearing an S18A (α 1 -S18A) mutation, which precludes PKCζ phosphorylation, stabilized the Na,K-ATPase at the plasma membrane and prevented hypoxia-induced cell death even in the absence of HOIL-1L. Adenoviral overexpression of the α 1 -S18A mutant Na,K-ATPase in vivo rescued the enhanced sensitivity of Cre SPC/ HOIL-1L fl/fl mice to hypoxic lung injury. These data suggest that stabilization of Na,K-ATPase during severe hypoxia is a HIF-dependent process involving PKCζ degradation. Accordingly, we provide evidence of an important adaptive mechanism to severe hypoxia, whereby halting the exaggerated down-regulation of plasma membrane Na,K-ATPase prevents cell death and lung injury.

Reappraising the ultimatum: an fMRI study of emotion regulation and decision making.

PubMed

Grecucci, Alessandro; Giorgetta, Cinzia; Van't Wout, Mascha; Bonini, Nicolao; Sanfey, Alan G

2013-02-01

Emotion regulation strategies provide a means by which to modulate our social behavior. In this study, we investigated the effect of using reappraisal to both up- and downregulate social decision making. After being instructed on how to use reappraisal, participants played the Ultimatum Game while undergoing functional magnetic resonance imaging and applied the strategies of upregulation (reappraising the proposer's intentions as more negative), down-regulation (reappraising the proposer's intentions as less negative), as well as a baseline "look" condition. As hypothesized, when reappraising, decision acceptance rates were altered, with a greater number of unfair offers accepted while down-regulating and a greater number of unfair offers rejected while upregulating, both relative to the baseline condition. At the neural level, during reappraisal, significant activations were observed in the inferior and middle frontal gyrus (MFG), in addition to the medial prefrontal cortex and cingulate gyrus for unfair offers only. Regulated decisions involved left inferior frontal gyrus for upregulation and MFG for down-regulation strategies, respectively. Importantly, the effects of emotion modulation were evident in posterior insula, with less activation for down-regulation and more activation for upregulation in these areas. Notably, we show for the first time that top-down strategies such as reappraisal strongly affect our socioeconomic decisions.

GLI pathogenesis-related 1 functions as a tumor-suppressor in lung cancer.

PubMed

Sheng, Xiumei; Bowen, Nathan; Wang, Zhengxin

2016-03-18

GLI pathogenesis-related 1 (GLIPR1) was originally identified in glioblastomas and its expression was also found to be down-regulated in prostate cancer. Functional studies revealed both growth suppression and proapoptotic activities for GLIPR1 in multiple cancer cell lines. GLIPR1's role in lung cancer has not been investigated. Protein arginine methyltransferase 5 (PRMT5) is a protein arginine methyltransferase and forms a stoichiometric complex with the WD repeat domain 77 (WDR77) protein. Both PRMT5 and WDR77 are essential for growth of lung epithelial and cancer cells. But additional gene products that interact genetically or biochemichally with PRMT5 and WDR77 in the control of lung cancer cell growth are not characterized. DNA microarray and immunostaining were used to detect GLIPR1 expression during lung development and lung tumorigenesis. GLIPR1 expression was also analyzed in the TCGA lung cancer cohort. The consequence of GLIPR1 on growth of lung cancer cells in the tissue culture and lung tumor xenografts in the nude mice was observed. We found that GLIPR1 expression is negatively associated with PRMT5/WDR77. GLIPR1 is absent in growing epithelial cells at the early stages of mouse lung development and highly expressed in the adult lung. Expression of GLIPR1 was down-regulated during lung tumorigenesis and its expression suppressed growth of lung cancer cells in the tissue culture and lung tumor xenografts in mice. GLIPR1 regulates lung cancer growth through the V-Erb-B avian erythroblastic leukemia viral oncogene homolog 3 (ErbB3). This study reveals a novel pathway that PRMT5/WDR77 regulates GLIPR1 expression to control lung cancer cell growth and GLIPR1 as a potential therapeutic agent for lung cancer.

Transcriptome analysis of the brain of the silkworm Bombyx mori infected with Bombyx mori nucleopolyhedrovirus: A new insight into the molecular mechanism of enhanced locomotor activity induced by viral infection.

PubMed

Wang, Guobao; Zhang, Jianjia; Shen, Yunwang; Zheng, Qin; Feng, Min; Xiang, Xingwei; Wu, Xiaofeng

2015-06-01

Baculoviruses have been known to induce hyperactive behavior in their lepidopteran hosts for over a century. As a typical lepidopteran insect, the silkworm Bombyx mori displays enhanced locomotor activity (ELA) following infection with B. mori nucleopolyhedrovirus (BmNPV). Some investigations have focused on the molecular mechanisms underlying this abnormal hyperactive wandering behavior due to the virus; however, there are currently no reports about B. mori. Based on previous studies that have revealed that behavior is controlled by the central nervous system, the transcriptome profiles of the brains of BmNPV-infected and non-infected silkworm larvae were analyzed with the RNA-Seq technique to reveal the changes in the BmNPV-infected brain on the transcriptional level and to provide new clues regarding the molecular mechanisms that underlies BmNPV-induced ELA. Compared with the controls, a total of 742 differentially expressed genes (DEGs), including 218 up-regulated and 524 down-regulated candidates, were identified, of which 499, 117 and 144 DEGs could be classified into GO categories, KEGG pathways and COG annotations by GO, KEGG and COG analyses, respectively. We focused our attention on the DEGs that are involved in circadian rhythms, synaptic transmission and the serotonin receptor signaling pathway of B. mori. Our analyses suggested that these genes were related to the locomotor activity of B. mori via their essential roles in the regulations of a variety of behaviors and the down-regulation of their expressions following BmNPV infection. These results provide new insight into the molecular mechanisms of BmNPV-induced ELA. Copyright © 2015 Elsevier Inc. All rights reserved.

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

Byun, Eui-Baek; Choi, Han-Gyu; Sung, Nak-Yun

Highlights: Black-Right-Pointing-Pointer Expressions of CD80, CD86, and MHC class I/II were inhibited by EGCG via 67LR. Black-Right-Pointing-Pointer EGCG-treated DCs inhibited LPS-induced pro-inflammatory cytokines via 67LR. Black-Right-Pointing-Pointer EGCG-treated DCs inhibited MAPKs activation and NF-{kappa}B p65 translocation via 67LR. Black-Right-Pointing-Pointer EGCG elevated the expression of the Tollip protein through 67LR in DCs. -- Abstract: Epigallocatechin-3-gallate (EGCG), a major active polyphenol of green tea, has been shown to down-regulate inflammatory responses in dendritic cells (DCs); however, the underlying mechanism has not been understood. Recently, we identified the 67-kDa laminin receptor (67LR) as a cell-surface EGCG receptor. In this study, we showed the molecularmore » basis for the down-regulation of toll-like receptor 4 (TLR4) signal transduction by EGCG in DCs. The expressions of CD80, CD86, and MHC class I and II, which are molecules essential for antigen presentation by DCs, were inhibited by EGCG via 67LR. In addition, EGCG-treated DCs inhibited lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines (tumor necrosis factor [TNF]-{alpha}, interleukin [IL]-1{beta}, and IL-6) and activation of mitogen-activated protein kinases (MAPKs), e.g., extracellular signal-regulated kinase 1/2 (ERK1/2), p38, c-Jun N-terminal kinase (JNK), and nuclear factor {kappa}B (NF-{kappa}B) p65 translocation through 67LR. Interestingly, we also found that EGCG markedly elevated the expression of the Tollip protein, a negative regulator of TLR signaling, through 67LR. These novel findings provide new insight into the understanding of negative regulatory mechanisms of the TLR4 signaling pathway and consequent inflammatory responses that are implicated in the development and progression of many chronic diseases.« less

Motor Development in Children with Down Syndrome.

ERIC Educational Resources Information Center

Jobling, Anne

Assessment is an essential process for Physical Education program planning. This is especially true for children with special needs, such as children with Down Syndrome. The ultimate aim of assessments is to enable an informed and intelligent progam of planned activites. For children with Down Syndrome, there are no clear data on their overall…

Down-Regulation of p53 by Double-Stranded RNA Modulates the Antiviral Response

PubMed Central

Marques, Joao T.; Rebouillat, Dominique; Ramana, Chilakamarti V.; Murakami, Junko; Hill, Jason E.; Gudkov, Andrei; Silverman, Robert H.; Stark, George R.; Williams, Bryan R. G.

2005-01-01

p53 has been well characterized as a tumor suppressor gene, but its role in antiviral defense remains unclear. A recent report has demonstrated that p53 can be induced by interferons and is activated after vesicular stomatitis virus (VSV) infection. We observed that different nononcogenic viruses, including encephalomyocarditis virus (EMCV) and human parainfluenza virus type 3 (HPIV3), induced down-regulation of p53 in infected cells. Double-stranded RNA (dsRNA) and a mutant vaccinia virus lacking the dsRNA binding protein E3L can also induce this effect, indicating that dsRNA formed during viral infection is likely the trigger for down-regulation of p53. The mechanism of down-regulation of p53 by dsRNA relies on translation inhibition mediated by the PKR and RNase L pathways. In the absence of p53, the replication of both EMCV and HPIV3 was retarded, whereas, conversely, VSV replication was enhanced. Cell cycle analysis indicated that wild-type (WT) but not p53 knockout (KO) fibroblasts undergo an early-G1 arrest following dsRNA treatment. Moreover, in WT cells the onset of dsRNA-induced apoptosis begins after p53 levels are down-regulated, whereas p53 KO cells, which lack the early-G1 arrest, rapidly undergo apoptosis. Hence, our data suggest that the down-regulation of p53 facilitates apoptosis, thereby limiting viral replication. PMID:16103161

Metastatic Melanoma Secreted IL-10 Down-Regulates CD1 Molecules on Dendritic Cells in Metastatic Tumor Lesions

PubMed Central

Gerlini, Gianni; Tun-Kyi, Adrian; Dudli, Christa; Burg, Günter; Pimpinelli, Nicola; Nestle, Frank O.

2004-01-01

CD1 molecules are expressed by antigen-presenting cells such as dendritic cells and mediate primary immune responses to lipids and glycolipids which have been shown to be expressed by various tumors. Glycolipids are expressed by melanoma cells but, despite their immunogenicity, no efficient spontaneous immune responses are elicited. As IL-10 has previously been shown to down-regulate CD1a on dendritic cells and is known to be expressed by various melanoma cell lines, we investigated if melanoma-derived IL-10 could down-regulate CD1 molecule expression on dendritic cells as a possible way to circumvent immune recognition. We found that CD1a, CD1b, CD1c, and CD1d were significantly down-regulated on dendritic cells in metastatic (n = 10) but not in primary melanoma lesions (n = 10). We further detected significantly higher IL-10 protein levels in metastatic than in primary melanomas. Moreover, supernatants from metastatic melanomas were significantly more effective in down-regulating CD1 molecules on dendritic cells than supernatants from primary melanoma cultures. This effect was blocked using a neutralizing IL-10 antibody in a dose dependent manner. Our findings suggest that metastatic but not primary melanomas can down-regulate CD1 molecules on infiltrating dendritic cells by secreting IL-10 which may represent a novel way to escape the immune response directed against the tumor. PMID:15579430

LncRNA IDH1-AS1 links the functions of c-Myc and HIF1α via IDH1 to regulate the Warburg effect

PubMed Central

Xiang, Shaoxun; Gu, Hao; Thorne, Rick F.; Zhang, Xu Dong; Wu, Mian

2018-01-01

The oncoprotein c-Myc plays an important role in regulating glycolysis under normoxia; yet, in cancer cells, HIF1α, which is essential for driving glycolysis under hypoxia, is often up-regulated even in the presence of oxygen. The relationship between these two major regulators of the Warburg effect remains to be fully defined. Here we demonstrate that regulation of a long noncoding RNA (lncRNA), named IDH1-AS1, enables c-Myc to collaborate with HIF1α in activating the Warburg effect under normoxia. c-Myc transcriptionally repressed IDH1-AS1, which, upon expression, promoted homodimerization of IDH1 and thus enhanced its enzymatic activity. This resulted in increased α-KG and decreased ROS production and subsequent HIF1α down-regulation, leading to attenuation of glycolysis. Hence, c-Myc repression of IDH1-AS1 promotes activation of the Warburg effect by HIF1α. As such, IDH1-AS1 overexpression inhibited cell proliferation, whereas silencing of IDH1-AS1 promoted cell proliferation and cancer xenograft growth. Restoring IDH1-AS1 expression may therefore represent a potential metabolic approach for cancer treatment. PMID:29378948

Ca2+/Calmodulin-dependent kinase II signaling causes skeletal overgrowth and premature chondrocyte maturation.

PubMed

Taschner, Michael J; Rafigh, Mehran; Lampert, Fabienne; Schnaiter, Simon; Hartmann, Christine

2008-05-01

The long bones of vertebrate limbs originate from cartilage templates and are formed by the process of endochondral ossification. This process requires that chondrocytes undergo a progressive maturation from proliferating to postmitotic prehypertrophic to mature, hypertrophic chondrocytes. Coordinated control of proliferation and maturation regulates growth of the skeletal elements. Various signals and pathways have been implicated in orchestrating these processes, but the underlying intracellular molecular mechanisms are often not entirely known. Here we demonstrated in the chick using replication-competent retroviruses that constitutive activation of Calcium/Calmodulin-dependent kinase II (CaMKII) in the developing wing resulted in elongation of skeletal elements associated with premature differentiation of chondrocytes. The premature maturation of chondrocytes was a cell-autonomous effect of constitutive CaMKII signaling associated with down-regulation of cell-cycle regulators and up-regulation of chondrocyte maturation markers. In contrast, the elongation of the skeletal elements resulted from a non-cell autonomous up-regulation of the Indian hedgehog responsive gene encoding Parathyroid-hormone-related peptide. Reduction of endogenous CaMKII activity by overexpressing an inhibitory peptide resulted in shortening of the skeletal elements associated with a delay in chondrocyte maturation. Thus, CaMKII is an essential component of intracellular signaling pathways regulating chondrocyte maturation.

Central roles of iron in the regulation of oxidative stress in the yeast Saccharomyces cerevisiae.

PubMed

Matsuo, Ryo; Mizobuchi, Shogo; Nakashima, Maya; Miki, Kensuke; Ayusawa, Dai; Fujii, Michihiko

2017-10-01

Oxygen is essential for aerobic organisms but causes cytotoxicity probably through the generation of reactive oxygen species (ROS). In this study, we screened for the genes that regulate oxidative stress in the yeast Saccharomyces cerevisiae, and found that expression of CTH2/TIS11 caused an increased resistance to ROS. CTH2 is up-regulated upon iron starvation and functions to remodel metabolism to adapt to iron starvation. We showed here that increased resistance to ROS by CTH2 would likely be caused by the decreased ROS production due to the decreased activity of mitochondrial respiration, which observation is consistent with the fact that CTH2 down-regulates the mitochondrial respiratory proteins. We also found that expression of CTH1, a paralog of CTH2, also caused an increased resistance to ROS. This finding supported the above view, because mitochondrial respiratory proteins are the common targets of CTH1 and CTH2. We further showed that supplementation of iron in medium augmented the growth of S. cerevisiae under oxidative stress, and expression of CTH2 and supplementation of iron collectively enhanced its growth under oxidative stress. Since CTH2 is regulated by iron, these findings suggested that iron played crucial roles in the regulation of oxidative stress in S. cerevisiae.

TET1 and TET3 are essential in induction of Th2-type immunity partly through regulation of IL-4/13A expression in zebrafish model.

PubMed

Yang, Chao; Li, Zhuo; Kang, Wei; Tian, Yu; Yan, Yuzhu; Chen, Wei

2016-10-10

It has been considered that epigenetic modulation can affect a diverse array of cellular activities, in which ten eleven translocation (TET) methylcytosine dioxygenase family members refer to a group of fundamental components involved in catalyzation of 5-hydroxymethylcytosine and modification of gene expression. Even though the function of TET proteins has been gradually revealed, their roles in immune regulation are still largely unknown. Recent studies provided clues that TET2 could regulate several innate immune-related inflammatory mediators in mammals. This study sought to explore the function of TET family members in potential T-helper (Th) cell differentiation involved in adaptive immunity by utilizing a zebrafish model. As shown by results, soluble antigens could induce expression of zebrafish IL-4/13A (i.e. a pivotal Th2-type cytokine essential in Th2 cell differentiation and functions), and further trigger the expression of Th1- and Th2-related genes. It is noteworthy that this response was accompanied by the up-regulation of two TET family members (TET1 and TET3) both in immune organs (spleen and kidney) and cells (peripheral lymphocytes). Knocking-down of TET1 and TET3 will give rise to the decreased responses of IL-4/13A induction against exogenous soluble antigen stimulation, and further restrain the expression of Th2-related genes, which indicates a restrained Th2 cell differentiation. Nonetheless, TET2 did not exhibit effect on the modification of Th1/Th2 related gene expression. Hence, these data showed that TET1 and TET3 might be two significant epigenetic regulators involved in Th2 differentiation through regulation of IL-4/13A expression. This is the first report to show that TET family members play indispensable roles in Th2-type immunity, indicating an epigenetic modulation manner involved in adaptive immune regulations and responses. Copyright © 2016 Elsevier B.V. All rights reserved.

Overlapping Podospora anserina Transcriptional Responses to Bacterial and Fungal Non Self Indicate a Multilayered Innate Immune Response

PubMed Central

Lamacchia, Marina; Dyrka, Witold; Breton, Annick; Saupe, Sven J.; Paoletti, Mathieu

2016-01-01

Recognition and response to non self is essential to development and survival of all organisms. It can occur between individuals of the same species or between different organisms. Fungi are established models for conspecific non self recognition in the form of vegetative incompatibility (VI), a genetically controlled process initiating a programmed cell death (PCD) leading to the rejection of a fusion cell between genetically different isolates of the same species. In Podospora anserina VI is controlled by members of the hnwd gene family encoding for proteins analogous to NOD Like Receptors (NLR) immune receptors in eukaryotes. It was hypothesized that the hnwd controlled VI reaction was derived from the fungal innate immune response. Here we analyze the P. anserina transcriptional responses to two bacterial species, Serratia fonticola to which P. anserina survives and S. marcescens to which P. anserina succumbs, and compare these to the transcriptional response induced under VI conditions. Transcriptional responses to both bacteria largely overlap, however the number of genes regulated and magnitude of regulation is more important when P. anserina survives. Transcriptional responses to bacteria also overlap with the VI reaction for both up or down regulated gene sets. Genes up regulated tend to be clustered in the genome, and display limited phylogenetic distribution. In all three responses we observed genes related to autophagy to be up-regulated. Autophagy contributes to the fungal survival in all three conditions. Genes encoding for secondary metabolites and histidine kinase signaling are also up regulated in all three conditions. Transcriptional responses also display differences. Genes involved in response to oxidative stress, or encoding small secreted proteins are essentially expressed in response to bacteria, while genes encoding NLR proteins are expressed during VI. Most functions encoded in response to bacteria favor survival of the fungus while most functions up regulated during VI would lead to cell death. These differences are discussed in the frame of a multilayered response to non self in fungi. PMID:27148175

Aspirin augments the expression of Adenomatous Polyposis Coli protein by suppression of IKKβ

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

Ashida, Noboru, E-mail: nashida@kuhp.kyoto-u.ac.jp; Kishihata, Masako; Tien, Dat Nguyen

Highlights: • Clinical studies revealed aspirin inhibits cancer, but the mechanism is not known. • Adenomatous Polyposis Coli (APC) is a well-known tumor-suppressing gene. • We found aspirin up-regulates the protein of APC. • Aspirin suppressed the expression of IKKβ, an essential kinase in NFκB activation. • The deletion of IKKβ significantly increases the expression of APC protein. - Abstract: Aspirin has been widely used as analgesic, antipyretic and anti-inflammatory medicine for long. In addition to these traditional effects, clinical studies suggest that aspirin can protect against cancer, but its mechanism has not been explored. To unveil it, we identifiedmore » the proteins up- or down-regulated after incubation with aspirin by using proteomics analysis with Nano-flow LC/MALDI-TOF system. Interestingly, the analysis identified the protein of Adenomatous Polyposis Coli (APC) as one of the most up-regulated protein. APC regulates cell proliferation or angiogenesis, and is widely known as a tumor-suppressing gene which can cause colorectal cancer when it is mutated. Western blots confirmed this result, and real-time PCR indicated it is transcriptionally regulated. We further tried to elucidate the molecular mechanism with focusing on IKKβ. IKKβ is the essential kinase in activation of nuclear factor-kappa B (NF-κB), major transcriptional factors that regulate genes responsible for inflammation or immune response. Previous reports indicated that aspirin specifically inhibits IKKβ activity, and constitutively active form of IKKβ accelerates APC loss. We found that aspirin suppressed the expression of IKKβ, and the deletion of IKKβ by siRNA increases the expression of APC in HEK294 cells. Finally, we observed similar effects of aspirin in human umbilical vein endothelial cells. Taken together, these results reveal that aspirin up-regulates the expression of APC via the suppression of IKKβ. This can be a mechanism how aspirin prevents cancer at least in part, and a novel link between inflammatory NF-κB signaling and cancer.« less

HSP90 is a therapeutic target in JAK2-dependent myeloproliferative neoplasms in mice and humans

PubMed Central

Marubayashi, Sachie; Koppikar, Priya; Taldone, Tony; Abdel-Wahab, Omar; West, Nathan; Bhagwat, Neha; Caldas-Lopes, Eloisi; Ross, Kenneth N.; Gönen, Mithat; Gozman, Alex; Ahn, James H.; Rodina, Anna; Ouerfelli, Ouathek; Yang, Guangbin; Hedvat, Cyrus; Bradner, James E.; Chiosis, Gabriela; Levine, Ross L.

2010-01-01

JAK2 kinase inhibitors were developed for the treatment of myeloproliferative neoplasms (MPNs), following the discovery of activating JAK2 mutations in the majority of patients with MPN. However, to date JAK2 inhibitor treatment has shown limited efficacy and apparent toxicities in clinical trials. We report here that an HSP90 inhibitor, PU-H71, demonstrated efficacy in cell line and mouse models of the MPN polycythemia vera (PV) and essential thrombocytosis (ET) by disrupting JAK2 protein stability. JAK2 physically associated with both HSP90 and PU-H71 and was degraded by PU-H71 treatment in vitro and in vivo, demonstrating that JAK2 is an HSP90 chaperone client. PU-H71 treatment caused potent, dose-dependent inhibition of cell growth and signaling in JAK2 mutant cell lines and in primary MPN patient samples. PU-H71 treatment of mice resulted in JAK2 degradation, inhibition of JAK-STAT signaling, normalization of peripheral blood counts, and improved survival in MPN models at doses that did not degrade JAK2 in normal tissues or cause substantial toxicity. Importantly, PU-H71 treatment also reduced the mutant allele burden in mice. These data establish what we believe to be a novel therapeutic rationale for HSP90 inhibition in the treatment of JAK2-dependent MPN. PMID:20852385

Microarray analysis of gene regulations and potential association with acephate-resistance and fitness cost in Lygus lineolaris.

PubMed

Zhu, Yu Cheng; Guo, Zibiao; He, Yueping; Luttrell, Randall

2012-01-01

The tarnished plant bug has become increasingly resistant to organophosphates in recent years. To better understand acephate resistance mechanisms, biological, biochemical, and molecular experiments were systematically conducted with susceptible (LLS) and acephate-selected (LLR) strains. Selection of a field population with acephate significantly increased resistance ratio to 5.9-fold, coupled with a significant increase of esterase activities by 2-fold. Microarray analysis of 6,688 genes revealed 329 up- and 333 down-regulated (≥2-fold) genes in LLR. Six esterase, three P450, and one glutathione S-transferase genes were significantly up-regulated, and no such genes were down-regulated in LLR. All vitellogenin and eggshell protein genes were significantly down-regulated in LLR. Thirteen protease genes were significantly down-regulated and only 3 were up-regulated in LLR. More than twice the number of catalysis genes and more than 3.6-fold of metabolic genes were up-regulated, respectively, as compared to those down-regulated with the same molecular and biological functions. The large portion of metabolic or catalysis genes with significant up-regulations indicated a substantial increase of metabolic detoxification in LLR. Significant increase of acephate resistance, increases of esterase activities and gene expressions, and variable esterase sequences between LLS and LLR consistently demonstrated a major esterase-mediated resistance in LLR, which was functionally provable by abolishing the resistance with esterase inhibitors. In addition, significant elevation of P450 gene expression and reduced susceptibility to imidacloprid in LLR indicated a concurrent resistance risk that may impact other classes of insecticides. This study demonstrated the first association of down-regulation of reproductive- and digestive-related genes with resistance to conventional insecticides, suggesting potential fitness costs associated with resistance development. This study shed new light on the understanding of the molecular basis of insecticide resistance, and the information is highly valuable for development of chemical control guidelines and tactics to minimize resistance and cross-resistance risks.

Down-regulation of Glutathione S-transferase Pi in Asthma Contributes to Enhanced Oxidative Stress

PubMed Central

Schroer, Kathy T.; Gibson, Aaron M.; Sivaprasad, Umasundari; Bass, Stacey A.; Ericksen, Mark B.; Wills-Karp, Marsha; LeCras, Tim; Fitzpatrick, Anne M.; Brown, Lou Ann S.; Stringer, Keith F.; Khurana Hershey, Gurjit K.

2011-01-01

Background Glutathione S-transferase Pi (GSTPi) is the predominant redox regulator in the lung. While evidence implicates an important role for GSTPi in asthma, the mechanism for this has remained elusive. Objectives To determine how GSTPi is regulated in asthma and to elucidate its role in maintaining redox homeostasis. Methods We elucidated the regulation of GSTPi in children with asthma and utilized murine models of asthma to determine the role of GSTPi in redox homeostasis. Measurements and Main Results Our findings demonstrate that GSTPi transcript levels are markedly down-regulated in allergen and IL-13 treated mouse models of asthma via STAT6 dependent and independent pathways. Nuclear factor-erythroid 2 related factor 2 (Nrf2) was also down-regulated in these models. The decrease in GSTPi expression was associated with decreased total GST activity in the lungs of mice. Examination of cystine intermediates uncovered a functional role for GSTPi in regulating Cys oxidation, whereby GSTPi-deficient mice exhibited increased oxidative stress (increase in % cystine) compared with wild-type mice following allergen challenge. GSTPi expression was similarly down-regulated in children with asthma. Conclusions These data collectively suggest that down-regulation of GSTPi following allergen challenge may contribute to the asthma phenotype due to disruption of redox homeostasis and increased oxidative stress. Furthermore, GSTPi may be an important therapeutic target for asthma, and evaluation of GSTPi expression may prove beneficial in identifying individuals who would benefit from therapy targeting this pathway. PMID:21570714

MicroRNA-193b represses cell proliferation and regulates cyclin D1 in melanoma.

PubMed

Chen, Jiamin; Feilotter, Harriet E; Paré, Geneviève C; Zhang, Xiao; Pemberton, Joshua G W; Garady, Cherif; Lai, Dulcie; Yang, Xiaolong; Tron, Victor A

2010-05-01

Cutaneous melanoma is an aggressive form of human skin cancer characterized by high metastatic potential and poor prognosis. To better understand the role of microRNAs (miRNAs) in melanoma, the expression of 470 miRNAs was profiled in tissue samples from benign nevi and metastatic melanomas. We identified 31 miRNAs that were differentially expressed (13 up-regulated and 18 down-regulated) in metastatic melanomas relative to benign nevi. Notably, miR-193b was significantly down-regulated in the melanoma tissues examined. To understand the role of miR-193b in melanoma, functional studies were undertaken. Overexpression of miR-193b in melanoma cell lines repressed cell proliferation. Gene expression profiling identified 314 genes down-regulated by overexpression of miR-193b in Malme-3M cells. Eighteen of these down-regulated genes, including cyclin D1 (CCND1), were also identified as putative miR-193b targets by TargetScan. Overexpression of miR-193b in Malme-3M cells down-regulated CCND1 mRNA and protein by > or = 50%. A luciferase reporter assay confirmed that miR-193b directly regulates CCND1 by binding to the 3'untranslated region of CCND1 mRNA. These studies indicate that miR-193b represses cell proliferation and regulates CCND1 expression and suggest that dysregulation of miR-193b may play an important role in melanoma development.

MicroRNA-193b Represses Cell Proliferation and Regulates Cyclin D1 in Melanoma

PubMed Central

Chen, Jiamin; Feilotter, Harriet E.; Paré, Geneviève C.; Zhang, Xiao; Pemberton, Joshua G.W.; Garady, Cherif; Lai, Dulcie; Yang, Xiaolong; Tron, Victor A.

2010-01-01

Cutaneous melanoma is an aggressive form of human skin cancer characterized by high metastatic potential and poor prognosis. To better understand the role of microRNAs (miRNAs) in melanoma, the expression of 470 miRNAs was profiled in tissue samples from benign nevi and metastatic melanomas. We identified 31 miRNAs that were differentially expressed (13 up-regulated and 18 down-regulated) in metastatic melanomas relative to benign nevi. Notably, miR-193b was significantly down-regulated in the melanoma tissues examined. To understand the role of miR-193b in melanoma, functional studies were undertaken. Overexpression of miR-193b in melanoma cell lines repressed cell proliferation. Gene expression profiling identified 314 genes down-regulated by overexpression of miR-193b in Malme-3M cells. Eighteen of these down-regulated genes, including cyclin D1 (CCND1), were also identified as putative miR-193b targets by TargetScan. Overexpression of miR-193b in Malme-3M cells down-regulated CCND1 mRNA and protein by ≥50%. A luciferase reporter assay confirmed that miR-193b directly regulates CCND1 by binding to the 3′untranslated region of CCND1 mRNA. These studies indicate that miR-193b represses cell proliferation and regulates CCND1 expression and suggest that dysregulation of miR-193b may play an important role in melanoma development. PMID:20304954

Prediction of effective RNA interference targets and pathway-related genes in lepidopteran insects by RNA sequencing analysis.

PubMed

Guan, Ruo-Bing; Li, Hai-Chao; Miao, Xue-Xia

2018-06-01

When using RNA interference (RNAi) to study gene functions in Lepidoptera insects, we discovered that some genes could not be suppressed; instead, their expression levels could be up-regulated by double-stranded RNA (dsRNA). To predict which genes could be easily silenced, we treated the Asian corn borer (Ostrinia furnacalis) with dsGFP (green fluorescent protein) and dsMLP (muscle lim protein). A transcriptome sequence analysis was conducted using the cDNAs 6 h after treatment with dsRNA. The results indicated that 160 genes were up-regulated and 44 genes were down-regulated by the two dsRNAs. Then, 50 co-up-regulated, 25 co-down-regulated and 43 unaffected genes were selected to determine their RNAi responses. All the 25 down-regulated genes were knocked down by their corresponding dsRNA. However, several of the up-regulated and unaffected genes were up-regulated when treated with their corresponding dsRNAs instead of being knocked down. The genes up-regulated by the dsGFP treatment may be involved in insect immune responses or the RNAi pathway. When the immune-related genes were excluded, only seven genes were induced by dsGFP, including ago-2 and dicer-2. These results not only provide a reference for efficient RNAi target predications, but also provide some potential RNAi pathway-related genes for further study. © 2017 Institute of Zoology, Chinese Academy of Sciences.

TRX-1 Regulates SKN-1 Nuclear Localization Cell Non-autonomously in Caenorhabditis elegans

PubMed Central

McCallum, Katie C.; Liu, Bin; Fierro-González, Juan Carlos; Swoboda, Peter; Arur, Swathi; Miranda-Vizuete, Antonio; Garsin, Danielle A.

2016-01-01

The Caenorhabditis elegans oxidative stress response transcription factor, SKN-1, is essential for the maintenance of redox homeostasis and is a functional ortholog of the Nrf family of transcription factors. The numerous levels of regulation that govern these transcription factors underscore their importance. Here, we add a thioredoxin, encoded by trx-1, to the expansive list of SKN-1 regulators. We report that loss of trx-1 promotes nuclear localization of intestinal SKN-1 in a redox-independent, cell non-autonomous fashion from the ASJ neurons. Furthermore, this regulation is not general to the thioredoxin family, as two other C. elegans thioredoxins, TRX-2 and TRX-3, do not play a role in this process. Moreover, TRX-1-dependent regulation requires signaling from the p38 MAPK-signaling pathway. However, while TRX-1 regulates SKN-1 nuclear localization, classical SKN-1 transcriptional activity associated with stress response remains largely unaffected. Interestingly, RNA-Seq analysis revealed that loss of trx-1 elicits a general, organism-wide down-regulation of several classes of genes; those encoding for collagens and lipid transport being most prevalent. Together, these results uncover a novel role for a thioredoxin in regulating intestinal SKN-1 nuclear localization in a cell non-autonomous manner, thereby contributing to the understanding of the processes involved in maintaining redox homeostasis throughout an organism. PMID:26920757

TRX-1 Regulates SKN-1 Nuclear Localization Cell Non-autonomously in Caenorhabditis elegans.

PubMed

McCallum, Katie C; Liu, Bin; Fierro-González, Juan Carlos; Swoboda, Peter; Arur, Swathi; Miranda-Vizuete, Antonio; Garsin, Danielle A

2016-05-01

The Caenorhabditis elegans oxidative stress response transcription factor, SKN-1, is essential for the maintenance of redox homeostasis and is a functional ortholog of the Nrf family of transcription factors. The numerous levels of regulation that govern these transcription factors underscore their importance. Here, we add a thioredoxin, encoded by trx-1, to the expansive list of SKN-1 regulators. We report that loss of trx-1 promotes nuclear localization of intestinal SKN-1 in a redox-independent, cell non-autonomous fashion from the ASJ neurons. Furthermore, this regulation is not general to the thioredoxin family, as two other C. elegans thioredoxins, TRX-2 and TRX-3, do not play a role in this process. Moreover, TRX-1-dependent regulation requires signaling from the p38 MAPK-signaling pathway. However, while TRX-1 regulates SKN-1 nuclear localization, classical SKN-1 transcriptional activity associated with stress response remains largely unaffected. Interestingly, RNA-Seq analysis revealed that loss of trx-1 elicits a general, organism-wide down-regulation of several classes of genes; those encoding for collagens and lipid transport being most prevalent. Together, these results uncover a novel role for a thioredoxin in regulating intestinal SKN-1 nuclear localization in a cell non-autonomous manner, thereby contributing to the understanding of the processes involved in maintaining redox homeostasis throughout an organism. Copyright © 2016 by the Genetics Society of America.

Keratinocyte growth factor and the expression of wound-healing-related genes in primary human keratinocytes from burn patients.

PubMed

Chomiski, Verônica; Gragnani, Alfredo; Bonucci, Jéssica; Correa, Silvana Aparecida Alves; Noronha, Samuel Marcos Ribeiro de; Ferreira, Lydia Masako

2016-08-01

To evaluate the effect of keratinocyte growth factor (KGF) treatment on the expression of wound-healing-related genes in cultured keratinocytes from burn patients. Keratinocytes were cultured and divided into 4 groups (n=4 in each group): TKB (KGF-treated keratinocytes from burn patients), UKB (untreated keratinocytes from burn patients), TKC (KGF-treated keratinocytes from controls), and UKC (untreated keratinocytes from controls). Gene expression analysis using quantitative polymerase chain reaction (qPCR) array was performed to compare (1) TKC versus UKC, (2) UKB versus UKC, (3) TKB versus UKC, (4) TKB versus UKB, (5) TKB versus TKC, and (6) UKB versus TKC. Comparison 1 showed one down-regulated and one up-regulated gene; comparisons 2 and 3 resulted in the same five down-regulated genes; comparison 4 had no significant difference in relative gene expression; comparison 5 showed 26 down-regulated and 7 up-regulated genes; and comparison 6 showed 25 down-regulated and 11 up-regulated genes. There was no differential expression of wound-healing-related genes in cultured primary keratinocytes from burn patients treated with keratinocyte growth factor.

Neotenic phenomenon in gene expression in the skin of Foxn1- deficient (nude) mice - a projection for regenerative skin wound healing.

PubMed

Kur-Piotrowska, Anna; Kopcewicz, Marta; Kozak, Leslie P; Sachadyn, Pawel; Grabowska, Anna; Gawronska-Kozak, Barbara

2017-01-09

Mouse fetuses up to 16 day of embryonic development and nude (Foxn1- deficient) mice are examples of animals that undergo regenerative (scar-free) skin healing. The expression of transcription factor Foxn1 in the epidermis of mouse fetuses begins at embryonic day 16.5 which coincides with the transition point from scar-free to scar-forming skin wound healing. In the present study, we tested the hypothesis that Foxn1 expression in the skin is an essential condition to establish the adult skin phenotype and that Foxn1 inactivity in nude mice keeps skin in the immature stage resembling the phenomena of neoteny. Uninjured skin of adult C57BL/6J (B6) mice, mouse fetuses at days 14 (E14) and 18 (E18) of embryonic development and B6.Cg-Foxn1 nu (nude) mice were characterized for their gene expression profiles by RNA sequencing that was validated through qRT-PCR, Western Blot and immunohistochemistry. Differentially regulated genes indicated that nude mice were more similar to E14 (model of regenerative healing) and B6 were more similar to E18 (model of reparative healing). The up-regulated genes in nude and E14 mice were associated with tissue remodeling, cytoskeletal rearrangement, wound healing and immune response, whereas the down-regulated genes were associated with differentiation. E14 and nude mice exhibit prominent up-regulation of keratin (Krt23, -73, -82, -16, -17), involucrin (Ivl) and filaggrin (Flg2) genes. The transcription factors associated with the Hox genes known to specify cell fate during embryonic development and promote embryonic stem cells differentiation were down-regulated in both nude and E14. Among the genes enriched in the nude skin but not shared with E14 fetuses were members of the Wnt and matrix metalloproteinases (Mmps) families whereas Bmp and Notch related genes were down-regulated. In summary, Foxn1 appears to be a pivotal control element of the developmental program and skin maturation. Nude mice may be considered as a model of neoteny among mammals. The resemblance of gene expression profiles in the skin of both nude and E14 mice are direct or indirect consequences of the Foxn1 deficiency. Foxn1 appears to regulate the balance between cell proliferation and differentiation and its inactivity creates a pro-regenerative environment.

Emotion Regulation in Children with Down Syndrome.

ERIC Educational Resources Information Center

Smith, Maureen C.; Walden, Tedra A.

This study presents a preliminary exploration of emotion regulation in a sample of 20 children (ages 3-18 years) with Down Syndrome. Three aspects of emotion regulation (modulation, organization, flexibility) were predicted from emotion variables (affect intensity, affective expression, and autonomy-curiosity and motivation) in backward regression…

Functional overlap of top-down emotion regulation and generation: an fMRI study identifying common neural substrates between cognitive reappraisal and cognitively generated emotions.

PubMed

Otto, Benjamin; Misra, Supriya; Prasad, Aditya; McRae, Kateri

2014-09-01

One factor that influences the success of emotion regulation is the manner in which the regulated emotion was generated. Recent research has suggested that reappraisal, a top-down emotion regulation strategy, is more effective in decreasing self-reported negative affect when emotions were generated from the top-down, versus the bottom-up. On the basis of a process overlap framework, we hypothesized that the neural regions active during reappraisal would overlap more with emotions that were generated from the top-down, rather than from the bottom-up. In addition, we hypothesized that increased neural overlap between reappraisal and the history effects of top-down emotion generation would be associated with increased reappraisal success. The results of several analyses suggested that reappraisal and emotions that were generated from the top-down share a core network of prefrontal, temporal, and cingulate regions. This overlap is specific; no such overlap was observed between reappraisal and emotions that were generated in a bottom-up fashion. This network consists of regions previously implicated in linguistic processing, cognitive control, and self-relevant appraisals, which are processes thought to be crucial to both reappraisal and top-down emotion generation. Furthermore, individuals with high reappraisal success demonstrated greater neural overlap between reappraisal and the history of top-down emotion generation than did those with low reappraisal success. The overlap of these key regions, reflecting overlapping processes, provides an initial insight into the mechanism by which generation history may facilitate emotion regulation.

Left-right axis asymmetry determining human Cryptic gene is transcriptionally repressed by Snail.

PubMed

Gupta, Kartik; Pilli, Vijaya Satish Sekhar; Aradhyam, Gopala Krishna

2016-10-28

Establishment of the left-right axis is important for positioning organs asymmetrically in the developing vertebrate-embryo. A number of factors like maternally deposited molecules have emerged essential in initiating the specification of the axis; the downstream events, however, are regulated by signal-transduction and gene-expression changes identifying which remains a crucial challenge. The EGF-CFC family member Cryptic, that functions as a co-receptor for some TGF-beta ligands, is developmentally expressed in higher mammals and mutations in the gene cause loss or change in left-right axis asymmetry. Despite the strong phenotype, no transcriptional-regulator of this gene is known till date. Using promoter-analyses tools, we found strong evidence that the developmentally essential transcription factor Snail binds to the human Cryptic-promoter. We cloned the promoter-region of human Cryptic in a reporter gene and observed decreased Cryptic-promoter activation upon increasing Snail expression. Further, the expression of Cryptic is down-regulated upon exogenous Snail expression, validating the reporter assays and the previously identified role of Snail as a transcriptional repressor. Finally, we demonstrate using gel-shift assay that Snail in nuclear extract of PANC1 cells interacts with the promoter-construct bearing putative Snail binding sites and confirm this finding using chromatin immunoprecipitation assay. Snail represses the expression of human Cryptic and therefore, might affect the signaling via Nodal that has previously been demonstrated to specify the left-right axis using the EGF-CFC co-receptors.

How We Identify and Manage Patients with Inadequately Controlled Polycythemia Vera.

PubMed

Reiter, Andreas; Harrison, Claire

2016-10-01

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm (MPN) characterized by an overactive Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway through mutations in JAK2 exons 12 or 14 (JAK2 V617F). The dominant clinical characteristics include erythrocytosis (with or without leukocytosis/thrombocytosis), thrombotic events, and symptoms. Increased risk of mortality is mainly caused by thrombotic events and progression to post-polycythemia vera myelofibrosis (PPV-MF) or secondary acute myeloid leukemia (sAML). The most important prognostic factors include age and a history of thrombotic events, although recent evidence has indicated that leukocytosis and additional cytogenetic aberrations may also be of significant prognostic value. First-line therapies include aspirin and phlebotomies, which significantly reduce the incidence of thrombotic events and prolong survival. Cytoreductive treatment with hydroxyurea (approved) and conventional or pegylated interferon-α (effective, but not approved in many countries) is initiated for high-risk or inadequately controlled disease, e.g., uncontrolled hematocrit, leukocytosis, thrombocytosis, thrombotic events, splenomegaly, or symptoms. However, some patients may not receive initial benefit from first-line therapy or may become resistant or intolerant in due course. Although second-line treatment options are limited, clinical trials have shown the efficacy of ruxolitinib toward improving blood counts, enlarged spleen, and symptoms and potentially reducing thrombotic events. Identification of patients with uncontrolled PV is important for clinical care, as such patients have a high risk of complications, and future studies with JAK inhibitors or other agents alone or in combination are needed to test their potential to reduce rates of thrombotic events and transformation to PPV-MF or sAML.

Suspected myelodysplastic/myeloproliferative neoplasm in a feline leukemia virus-negative cat.

PubMed

Weeden, Amy L; Taylor, Kyle R; Terrell, Scott P; Gallagher, Alexander E; Wamsley, Heather L

2016-12-01

A 10-year-old castrated Domestic Short-Haired cat was presented to a primary care veterinarian for a wellness examination and laboratory examination for monitoring of diabetes mellitus. The CBC revealed marked thrombocytosis, leukopenia and macrocytic, normochromic anemia. The cat tested negative for FeLV and feline immunodeficiency virus, but was positive for Mycoplasma haemominutum by PCR. Hematologic abnormalities were not responsive to therapy, so a repeat CBC and a bone marrow aspiration for cytology were performed. Additional blood smear findings included anisocytosis with megaloblastic erythroid precursors, large platelets, eosinophilic myelocytes and metamyelocytes, and rare unidentified blasts. The bone marrow smear was highly cellular, and the cytologic pattern was consistent with myelodysplastic syndrome with an erythroid predominance. At that time, 15% blasts were present. The cat was treated with a vitamin K 2 analog, doxycycline, and prednisolone, but without a clinical response. Within 3 months, euthanasia was elected due to declining quality of life, and a necropsy was performed. Postmortem bone marrow smears were highly cellular and dominated by monomorphic blasts of unknown line of origin (52%), persistent marked erythroid and megakaryocytic dysplasia, and ineffective erythropoiesis and granulopoiesis. Immunohistochemical, immunocytochemical, and cytochemical stains resulted in a diagnosis of acute myeloid leukemia of unclassified type. Additional histologic findings included mixed hepatitis with trematode infestation and lymphoplasmacytic interstitial nephritis with fibrosis. The marked thrombocytosis with myelodysplastic syndrome and the FeLV-negative status of this cat were unusual. The difficulty in classifying the myelodysplasia and subsequent leukemia highlights a need for further reporting and characterization of these types of disease. © 2016 American Society for Veterinary Clinical Pathology.

Resolution of renal adenocarcinoma-induced secondary inappropriate polycythaemia after nephrectomy in two cats.

PubMed

Klainbart, Sigal; Segev, Gilad; Loeb, Emmanuel; Melamed, Dana; Aroch, Itamar

2008-07-01

Two cases of secondary, inappropriate polycythaemia caused by renal adenocarcinoma in domestic shorthair cats, are described. The cats were 9 and 12 years old and both were presented because of generalised seizures presumably due to hyperviscosity. Both cats had a markedly increased haematocrit (0.770 and 0.632 l/l) and thrombocytosis (744 x 10(9)/l and 926 x 10(9)/l). An abdominal ultrasound revealed a mass in the cranial pole of one kidney in both cats. Serum erythropoietin (EPO) concentration was within the reference interval (RI) in both cats but was inappropriately high considering the markedly increased haematocrit. The cats were initially stabilised and managed by multiple phlebotomies and intravenous fluid therapy and underwent nephrectomy of the affected kidney later on. Both the polycythaemia and thrombocytosis resolved following surgery. Postoperative serum EPO concentration, measured in one cat, decreased markedly. Histopathology of the affected kidneys confirmed a diagnosis of renal adenocarcinoma. Both cats were stable for an 8-month follow-up period; however, one cat had developed a stable chronic kidney disease (CKD), while the other was represented 8 months postoperatively due to dyspnoea, and had radiographic evidence of lung metastasis, presumably because of the spread of the original renal tumour and was euthanased. Initial stabilisation of polycythaemic cats should include multiple phlebotomies. Nephrectomy should be considered in cats with secondary, inappropriate, renal adenocarcinoma-related polycythaemia when only one kidney is affected by the tumour, and provided that the other kidney's function is satisfactory. Nephrectomy should be expected to resolve the polycythaemia and lead to normalisation of serum EPO concentration.

Rho-associated kinase (ROCK) function is essential for cell cycle progression, senescence and tumorigenesis.

PubMed

Kümper, Sandra; Mardakheh, Faraz K; McCarthy, Afshan; Yeo, Maggie; Stamp, Gordon W; Paul, Angela; Worboys, Jonathan; Sadok, Amine; Jørgensen, Claus; Guichard, Sabrina; Marshall, Christopher J

2016-01-14

Rho-associated kinases 1 and 2 (ROCK1/2) are Rho-GTPase effectors that control key aspects of the actin cytoskeleton, but their role in proliferation and cancer initiation or progression is not known. Here, we provide evidence that ROCK1 and ROCK2 act redundantly to maintain actomyosin contractility and cell proliferation and that their loss leads to cell-cycle arrest and cellular senescence. This phenotype arises from down-regulation of the essential cell-cycle proteins CyclinA, CKS1 and CDK1. Accordingly, while the loss of either Rock1 or Rock2 had no negative impact on tumorigenesis in mouse models of non-small cell lung cancer and melanoma, loss of both blocked tumor formation, as no tumors arise in which both Rock1 and Rock2 have been genetically deleted. Our results reveal an indispensable role for ROCK, yet redundant role for isoforms 1 and 2, in cell cycle progression and tumorigenesis, possibly through the maintenance of cellular contractility.

Mechanisms of antifungal and anti-aflatoxigenic properties of essential oil derived from turmeric (Curcuma longa L.) on Aspergillus flavus.

PubMed

Hu, Yichen; Zhang, Jinming; Kong, Weijun; Zhao, Gang; Yang, Meihua

2017-04-01

The antifungal activity and potential mechanisms in vitro as well as anti-aflatoxigenic efficiency in vivo of natural essential oil (EO) derived from turmeric (Curcuma longa L.) against Aspergillus flavus was intensively investigated. Based on the previous chemical characterization of turmeric EO by gas chromatography-mass spectrometry, the substantially antifungal activities of turmeric EO on the mycelial growth, spore germination and aflatoxin production were observed in a dose-dependent manner. Furthermore, these antifungal effects were related to the disruption of fungal cell endomembrane system including the plasma membrane and mitochondria, specifically i.e. the inhibition of ergosterol synthesis, mitochondrial ATPase, malate dehydrogenase, and succinate dehydrogenase activities. Moreover, the down-regulation profiles of turmeric EO on the relative expression of mycotoxin genes in aflatoxin biosynthetic pathway revealed its anti-aflatoxigenic mechanism. Finally, the suppression effect of fungal contamination in maize indicated that turmeric EO has potential as an eco-friendly antifungal agent. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of plant essential oils as acaricides against the poultry red mite, Dermanyssus gallinae, with special focus on exposure time.

PubMed

George, D R; Olatunji, G; Guy, J H; Sparagano, O A E

2010-04-19

Essential oils from thyme and cade have been shown to be effective acaricides against the poultry red mite, Dermanyssus gallinae (De Geer) when tested over a 24h period. Data on the actual rate of knock-down achieved with these products is lacking and potentially important as essential oils are likely to display only short-term toxicity. When tested over periods of less than 24h, thyme essential oil killed D. gallinae relatively quickly and so may make for an effective acaricide even if the residual toxicity of this product is low. However, cade essential oil did not display such a high level of mite knock-down, suggesting it may hold less promise in D. gallinae management. Comparison of the results with those obtained elsewhere using alternative D. gallinae products further confirms the possibility that thyme essential may be useful in control of this pest. This might be especially true if thyme essential oil were employed as part of an integrated pest management approach.

Emotion regulation of the affect-modulated startle reflex during different picture categories.

PubMed

Conzelmann, Annette; McGregor, Victoria; Pauli, Paul

2015-09-01

Previous studies on emotion regulation of the startle reflex found an increase in startle amplitude from down-, to non-, to up-regulation for pleasant and unpleasant stimuli. We wanted to clarify whether this regulation effect remains stable for different picture categories within pleasant and unpleasant picture sets. We assessed startle amplitude of 31 participants during down-, non-, or up-regulation of feelings elicited by pleasant erotic and adventure and unpleasant victim and threat pictures. Startle amplitude was smaller during adventure and erotic compared to victim and threat pictures and increased from down-, to non-, to up-regulation independently of the picture category. Results indicate that the motivational priming effect on startle modulation elicited by different picture categories is independent of emotion regulation instructions. In addition, the emotion regulation effect is independent of motivational priming effects. © 2015 Society for Psychophysiological Research.

Centriole assembly and the role of Mps1: defensible or dispensable?

PubMed

Pike, Amanda N; Fisk, Harold A

2011-04-14

The Mps1 protein kinase is an intriguing and controversial player in centriole assembly. Originally shown to control duplication of the budding yeast spindle pole body, Mps1 is present in eukaryotes from yeast to humans, the nematode C. elegans being a notable exception, and has also been shown to regulate the spindle checkpoint and an increasing number of cellular functions relating to genomic stability. While its function in the spindle checkpoint appears to be both universally conserved and essential in most organisms, conservation of its originally described function in spindle pole duplication has proven controversial, and it is less clear whether Mps1 is essential for centrosome duplication outside of budding yeast. Recent studies of Mps1 have identified at least two distinct functions for Mps1 in centriole assembly, while simultaneously supporting the notion that Mps1 is dispensable for the process. However, the fact that at least one centrosomal substrate of Mps1 is conserved from yeast to humans down to the phosphorylation site, combined with evidence demonstrating the exquisite control exerted over centrosomal Mps1 levels suggest that the notion of being essential may not be the most important of distinctions.

FUM2, a Cytosolic Fumarase, Is Essential for Acclimation to Low Temperature in Arabidopsis thaliana1[OPEN

PubMed Central

Dyson, Beth C.; Miller, Matthew A.E.; Feil, Regina; Rattray, Nicholas; Bowsher, Caroline G.

2016-01-01

Although cold acclimation is a key process in plants from temperate climates, the mechanisms sensing low temperature remain obscure. Here, we show that the accumulation of the organic acid fumaric acid, mediated by the cytosolic fumarase FUM2, is essential for cold acclimation of metabolism in the cold-tolerant model species Arabidopsis (Arabidopsis thaliana). A nontargeted metabolomic approach, using gas chromatography-mass spectrometry, identifies fumarate as a key component of the cold response in this species. Plants of T-DNA insertion mutants, lacking FUM2, show marked differences in their response to cold, with contrasting responses both in terms of metabolite concentrations and gene expression. The fum2 plants accumulated higher concentrations of phosphorylated sugar intermediates and of starch and malate. Transcripts for proteins involved in photosynthesis were markedly down-regulated in fum2.2 but not in wild-type Columbia-0. Plants of fum2 show a complete loss of the ability to acclimate photosynthesis to low temperature. We conclude that fumarate accumulation plays an essential role in low temperature sensing in Arabidopsis, either indirectly modulating metabolic or redox signals or possibly being itself directly involved in cold sensing. PMID:27440755

Top-down preparation modulates visual categorization but not subjective awareness of objects presented in natural backgrounds.

PubMed

Koivisto, Mika; Kahila, Ella

2017-04-01

Top-down processes are widely assumed to be essential in visual awareness, subjective experience of seeing. However, previous studies have not tried to separate directly the roles of different types of top-down influences in visual awareness. We studied the effects of top-down preparation and object substitution masking (OSM) on visual awareness during categorization of objects presented in natural scene backgrounds. The results showed that preparation facilitated categorization but did not influence visual awareness. OSM reduced visual awareness and impaired categorization. The dissociations between the effects of preparation and OSM on visual awareness and on categorization imply that they influence at different stages of cognitive processing. We propose that preparation influences at the top of the visual hierarchy, whereas OSM interferes with processes occurring at lower levels of the hierarchy. These lower level processes play an essential role in visual awareness. Copyright © 2017 Elsevier Ltd. All rights reserved.

Down-regulation of adenosine monophosphate-activated protein kinase activity: A driver of cancer.

PubMed

He, Xiaoling; Li, Cong; Ke, Rong; Luo, Lingyu; Huang, Deqiang

2017-04-01

Adenosine monophosphate-activated protein kinase (AMPK), a serine/threonine protein kinase, is known as "intracellular energy sensor and regulator." AMPK regulates multiple cellular processes including protein and lipid synthesis, cell proliferation, invasion, migration, and apoptosis. Moreover, AMPK plays a key role in the regulation of "Warburg effect" in cancer cells. AMPK activity is down-regulated in most tumor tissues compared with the corresponding adjacent paracancerous or normal tissues, indicating that the decline in AMPK activity is closely associated with the development and progression of cancer. Therefore, understanding the mechanism of AMPK deactivation during cancer progression is of pivotal importance as it may identify AMPK as a valid therapeutic target for cancer treatment. Here, we review the mechanisms by which AMPK is down-regulated in cancer.

Effect of dietary glutamine on tumor glutathione levels and apoptosis-related proteins in DMBA-induced breast cancer of rats.

PubMed

Todorova, Valentina K; Harms, Stacy A; Kaufmann, Yihong; Luo, Shaoke; Luo, Kevin Q; Babb, Kirk; Klimberg, V Suzanne

2004-12-01

Glutamine (GLN) is a non-essential amino acid that is present in nearly every biochemical pathway and is the major intraorgan nitrogen carrier. GLN via glutamate, is one of the precursors for the synthesis of glutathione (GSH), the major endogenous antioxidant in mammalian cells, which protects them from oxidative injury and cell death. Cancer cells have higher GSH levels than the surrounding normal cells, which attributes to a higher rate of cell proliferation and resistance to chemotherapy. Therefore, selective tumor depletion of GSH presents a promising strategy in cancer treatment. Experimental studies have associated decreased GSH levels with inhibition of proliferation and stimulation of apoptosis. Previous results of our laboratory have provided evidence that dietary GLN diminished tumor development in implantable as well as 7,12-dimethylbenz[a]anthracene (DMBA)-induced breast cancer and elevated GSH in the host tissues. In this study we examined the effects of GLN on GSH levels in DMBA-induced mammary tumors and correlated the results with protein and mRNA expression of apoptosis-related proteins Bcl-2, Bax and caspase-3 in tumor cells. The results have shown that GLN supplementation caused a significant decrease in the tumor GSH levels and the ratio GSH/oxidized GSH (GSSG), accompanied by up-regulation of Bax and caspase-3, and down-regulation of Bcl-2. These findings suggest that dietary GLN supplementation suppresses mammary carcinogenesis by activation of apoptosis in tumor cells and this probably is a result of GSH down-regulation.

Does prolonged pituitary down-regulation with gonadotropin-releasing hormone agonist improve the live-birth rate in in vitro fertilization treatment?

PubMed

Ren, Jianzhi; Sha, Aiguo; Han, Dongmei; Li, Ping; Geng, Jie; Ma, Chaihui

2014-07-01

To evaluate the effects of a prolonged duration of gonadotropin-releasing hormone agonist (GnRH-a) in pituitary down-regulation for controlled ovarian hyperstimulation (COH) on the live-birth rate in nonendometriotic women undergoing in vitro fertilization and embryo transfer (IVF-ET). Retrospective cohort study. University-affiliated hospital. Normogonadotropic women undergoing IVF. Three hundred seventy-eight patients receiving a prolonged pituitary down-regulation with GnRH-a before ovarian stimulation and 422 patients receiving a GnRH-a long protocol. Live-birth rate per fresh ET. In comparison with the long protocol, the prolonged down-regulation protocol required a higher total dose of gonadotropins. A lower serum luteinizing hormone (LH) level on the starting day of gonadotropin and the day of human chorionic gonadotropin (hCG) and a fewer number of oocytes and embryos were observed in the prolonged down-regulation protocol. However, the duration of stimulation and number of high-quality embryos were comparable between the two groups. A statistically significantly higher implantation rate (50.27% vs. 39.69%), clinical pregnancy rate (64.02% vs. 56.87%) and live-birth rate per fresh transfer cycle (55.56% vs. 45.73%) were observed in the prolonged protocol. Prolonged down-regulation in a GnRH-a protocol might increase the live-birth rates in normogonadotropic women. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Absence of regulation of human polymorphonuclear oxidative burst by interleukin-10, interleukin-4, interleukin-13 and transforming growth factor-beta in whole blood.

PubMed

Réglier-Poupet, H; Hakim, J; Gougerot-Pocidalo, M A; Elbim, C

1998-12-01

Cytokines such as IL-10, IL-4, IL-13 and TGF-beta play a major role in the regulation of immune responses and are considered as anti-inflammatory agents mainly due to their actions on monocytes. These cytokines are also known to participate in the regulation of PMN activities. However, few and contradictory results have been reported on their direct and priming effects on the PMN oxidative burst, which is essential for killing bacteria. We used a flow cytometry method to study the effects of these cytokines on the PMN oxidative burst; we also used whole blood to avoid PMN activation related to isolation procedures and in order to simulate the in vivo situation more closely. None of the cytokines tested had direct or priming effects on PMN H2O2 production. We also show for the first time that these cytokines do not modulate TNF priming of the PMN oxidative burst in response to N-formyl peptides (fMLP). These results show that the anti-bacterial activity of PMN, in terms of the PMN respiratory burst, is not down regulated by these anti-inflammatory cytokines in whole blood.

Cross-species microarray hybridization to identify developmentally regulated genes in the filamentous fungus Sordaria macrospora.

PubMed

Nowrousian, Minou; Ringelberg, Carol; Dunlap, Jay C; Loros, Jennifer J; Kück, Ulrich

2005-04-01

The filamentous fungus Sordaria macrospora forms complex three-dimensional fruiting bodies that protect the developing ascospores and ensure their proper discharge. Several regulatory genes essential for fruiting body development were previously isolated by complementation of the sterile mutants pro1, pro11 and pro22. To establish the genetic relationships between these genes and to identify downstream targets, we have conducted cross-species microarray hybridizations using cDNA arrays derived from the closely related fungus Neurospora crassa and RNA probes prepared from wild-type S. macrospora and the three developmental mutants. Of the 1,420 genes which gave a signal with the probes from all the strains used, 172 (12%) were regulated differently in at least one of the three mutants compared to the wild type, and 17 (1.2%) were regulated differently in all three mutant strains. Microarray data were verified by Northern analysis or quantitative real time PCR. Among the genes that are up- or down-regulated in the mutant strains are genes encoding the pheromone precursors, enzymes involved in melanin biosynthesis and a lectin-like protein. Analysis of gene expression in double mutants revealed a complex network of interaction between the pro gene products.

Disruptive environmental chemicals and cellular mechanisms that confer resistance to cell death.

PubMed

Narayanan, Kannan Badri; Ali, Manaf; Barclay, Barry J; Cheng, Qiang Shawn; D'Abronzo, Leandro; Dornetshuber-Fleiss, Rita; Ghosh, Paramita M; Gonzalez Guzman, Michael J; Lee, Tae-Jin; Leung, Po Sing; Li, Lin; Luanpitpong, Suidjit; Ratovitski, Edward; Rojanasakul, Yon; Romano, Maria Fiammetta; Romano, Simona; Sinha, Ranjeet K; Yedjou, Clement; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Amedei, Amedeo; Brown, Dustin G; Ryan, Elizabeth P; Colacci, Annamaria; Hamid, Roslida A; Mondello, Chiara; Raju, Jayadev; Salem, Hosni K; Woodrick, Jordan; Scovassi, A Ivana; Singh, Neetu; Vaccari, Monica; Roy, Rabindra; Forte, Stefano; Memeo, Lorenzo; Kim, Seo Yun; Bisson, William H; Lowe, Leroy; Park, Hyun Ho

2015-06-01

Cell death is a process of dying within biological cells that are ceasing to function. This process is essential in regulating organism development, tissue homeostasis, and to eliminate cells in the body that are irreparably damaged. In general, dysfunction in normal cellular death is tightly linked to cancer progression. Specifically, the up-regulation of pro-survival factors, including oncogenic factors and antiapoptotic signaling pathways, and the down-regulation of pro-apoptotic factors, including tumor suppressive factors, confers resistance to cell death in tumor cells, which supports the emergence of a fully immortalized cellular phenotype. This review considers the potential relevance of ubiquitous environmental chemical exposures that have been shown to disrupt key pathways and mechanisms associated with this sort of dysfunction. Specifically, bisphenol A, chlorothalonil, dibutyl phthalate, dichlorvos, lindane, linuron, methoxychlor and oxyfluorfen are discussed as prototypical chemical disruptors; as their effects relate to resistance to cell death, as constituents within environmental mixtures and as potential contributors to environmental carcinogenesis. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Polyamine pathway inhibition as a novel therapeutic approach to treating neuroblastoma

PubMed Central

Gamble, Laura D.; Hogarty, Michael D.; Liu, Xueyuan; Ziegler, David S.; Marshall, Glenn; Norris, Murray D.; Haber, Michelle

2012-01-01

Polyamines are highly regulated essential cations that are elevated in rapidly proliferating tissues, including diverse cancers. Expression analyses in neuroblastomas suggest that up-regulation of polyamine pro-synthetic enzymes and down-regulation of catabolic enzymes is associated with poor prognosis. Polyamine sufficiency may be required for MYCN oncogenicity in MYCN amplified neuroblastoma, and targeting polyamine homeostasis may therefore provide an attractive therapeutic approach. ODC1, an oncogenic MYCN target, is rate-limiting for polyamine synthesis, and is overexpressed in many cancers including neuroblastoma. Inhibition of ODC1 by difluoromethylornithine (DFMO) decreased tumor penetrance in TH-MYCN mice treated pre-emptively, and extended survival and synergized with chemotherapy in treating established tumors in both TH-MYCN and xenograft models. Efforts to augment DFMO activity, or otherwise maximally reduce polyamine levels, are focused on antagonizing polyamine uptake or augmenting polyamine export or catabolism. Since polyamine inhibition appears to be clinically well tolerated, these approaches, particularly when combined with chemotherapy, have great potential for improving neuroblastoma outcome in both MYCN amplified and non-MYCN amplified neuroblastomas. PMID:23181218

Attenuation of T cell receptor signaling by serine phosphorylation-mediated lysine 30 ubiquitination of SLP-76 protein.

PubMed

Wang, Xiaohong; Li, Ju-Pi; Chiu, Li-Li; Lan, Joung-Liang; Chen, Der-Yuan; Boomer, Jonathan; Tan, Tse-Hua

2012-10-05

SLP-76 (SH2 domain-containing leukocyte protein of 76 kDa) is an adaptor protein that is essential for T cell development and T cell receptor (TCR) signaling activation. Previous studies have identified an important negative feedback regulation of SLP-76 by HPK1 (hematopoietic progenitor kinase 1; MAP4K1)-induced Ser-376 phosphorylation. Ser-376 phosphorylation of SLP-76 mediates 14-3-3 binding, resulting in the attenuation of SLP-76 activation and downstream signaling; however, the underlying mechanism of this action remains unknown. Here, we report that phosphorylated SLP-76 is ubiquitinated and targeted for proteasomal degradation during TCR signaling. SLP-76 ubiquitination is mediated by Ser-376 phosphorylation. Furthermore, Lys-30 is identified as a ubiquitination site of SLP-76. Loss of Lys-30 ubiquitination of SLP-76 results in enhanced anti-CD3 antibody-induced ERK and JNK activation. These results reveal a novel regulation mechanism of SLP-76 by ubiquitination and proteasomal degradation of activated SLP-76, which is mediated by Ser-376 phosphorylation, leading to down-regulation of TCR signaling.

Attenuation of T Cell Receptor Signaling by Serine Phosphorylation-mediated Lysine 30 Ubiquitination of SLP-76 Protein*

PubMed Central

Wang, Xiaohong; Li, Ju-Pi; Chiu, Li-Li; Lan, Joung-Liang; Chen, Der-Yuan; Boomer, Jonathan; Tan, Tse-Hua

2012-01-01

SLP-76 (SH2 domain-containing leukocyte protein of 76 kDa) is an adaptor protein that is essential for T cell development and T cell receptor (TCR) signaling activation. Previous studies have identified an important negative feedback regulation of SLP-76 by HPK1 (hematopoietic progenitor kinase 1; MAP4K1)-induced Ser-376 phosphorylation. Ser-376 phosphorylation of SLP-76 mediates 14-3-3 binding, resulting in the attenuation of SLP-76 activation and downstream signaling; however, the underlying mechanism of this action remains unknown. Here, we report that phosphorylated SLP-76 is ubiquitinated and targeted for proteasomal degradation during TCR signaling. SLP-76 ubiquitination is mediated by Ser-376 phosphorylation. Furthermore, Lys-30 is identified as a ubiquitination site of SLP-76. Loss of Lys-30 ubiquitination of SLP-76 results in enhanced anti-CD3 antibody-induced ERK and JNK activation. These results reveal a novel regulation mechanism of SLP-76 by ubiquitination and proteasomal degradation of activated SLP-76, which is mediated by Ser-376 phosphorylation, leading to down-regulation of TCR signaling. PMID:22902619

Reconstruction of Tissue-Specific Metabolic Networks Using CORDA

PubMed Central

Schultz, André; Qutub, Amina A.

2016-01-01

Human metabolism involves thousands of reactions and metabolites. To interpret this complexity, computational modeling becomes an essential experimental tool. One of the most popular techniques to study human metabolism as a whole is genome scale modeling. A key challenge to applying genome scale modeling is identifying critical metabolic reactions across diverse human tissues. Here we introduce a novel algorithm called Cost Optimization Reaction Dependency Assessment (CORDA) to build genome scale models in a tissue-specific manner. CORDA performs more efficiently computationally, shows better agreement to experimental data, and displays better model functionality and capacity when compared to previous algorithms. CORDA also returns reaction associations that can greatly assist in any manual curation to be performed following the automated reconstruction process. Using CORDA, we developed a library of 76 healthy and 20 cancer tissue-specific reconstructions. These reconstructions identified which metabolic pathways are shared across diverse human tissues. Moreover, we identified changes in reactions and pathways that are differentially included and present different capacity profiles in cancer compared to healthy tissues, including up-regulation of folate metabolism, the down-regulation of thiamine metabolism, and tight regulation of oxidative phosphorylation. PMID:26942765

MiR-135 post-transcriptionally regulates FOXO1 expression and promotes cell proliferation in human malignant melanoma cells.

PubMed

Ren, Jian-Wen; Li, Zhang-Jun; Tu, Chen

2015-01-01

Malignant melanoma is the deadliest form of all skin cancers. Recently, microRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression by targeted repression of transcription and translation and play essential roles during cancer development. Our study showed that miR-135a is upregulated in malignant melanoma tissues and cell lines by using Real-time PCR assay. Enforced expression of miR-135a in malignant melanoma cells promotes cell proliferation, tumorigenicity, and cell cycle progression, whereas inhibition of miR-135a reverses the function. Additionally, we demonstrated FOXO1 is a direct target of miR-135a and transcriptionally down-regulated by miR-135a. Ectopic expression of miR-135a led to downregulation of the FOXO1 protein, resulting in upregulation of Cyclin D1, and downregulation of P21(Cip1) and P27(Kip1) through AKT pathway. Our findings suggested that miR-135a represents a potential onco-miRNA and plays an important role in malignant melanoma progression by suppressing FOXO1 expression.

SRC-2 orchestrates polygenic inputs for fine-tuning glucose homeostasis

PubMed Central

Fleet, Tiffany; Zhang, Bin; Lin, Fumin; Zhu, Bokai; Dasgupta, Subhamoy; Stashi, Erin; Tackett, Bryan; Thevananther, Sundararajah; Rajapakshe, Kimal I.; Gonzales, Naomi; Dean, Adam; Mao, Jianqiang; Timchenko, Nikolai; Malovannaya, Anna; Qin, Jun; Coarfa, Cristian; DeMayo, Francesco; Dacso, Clifford C.; Foulds, Charles E.; O’Malley, Bert W.; York, Brian

2015-01-01

Despite extensive efforts to understand the monogenic contributions to perturbed glucose homeostasis, the complexity of genetic events that fractionally contribute to the spectrum of this pathology remain poorly understood. Proper maintenance of glucose homeostasis is the central feature of a constellation of comorbidities that define the metabolic syndrome. The ability of the liver to balance carbohydrate uptake and release during the feeding-to-fasting transition is essential to the regulation of peripheral glucose availability. The liver coordinates the expression of gene programs that control glucose absorption, storage, and secretion. Herein, we demonstrate that Steroid Receptor Coactivator 2 (SRC-2) orchestrates a hierarchy of nutritionally responsive transcriptional complexes to precisely modulate plasma glucose availability. Using DNA pull-down technology coupled with mass spectrometry, we have identified SRC-2 as an indispensable integrator of transcriptional complexes that control the rate-limiting steps of hepatic glucose release and accretion. Collectively, these findings position SRC-2 as a major regulator of polygenic inputs to metabolic gene regulation and perhaps identify a previously unappreciated model that helps to explain the clinical spectrum of glucose dysregulation. PMID:26487680

Multiple interactions between RNA polymerase I, TIF-IA and TAF(I) subunits regulate preinitiation complex assembly at the ribosomal gene promoter.

PubMed

Yuan, Xuejun; Zhao, Jian; Zentgraf, Hanswalter; Hoffmann-Rohrer, Urs; Grummt, Ingrid

2002-11-01

In mammals, growth-dependent regulation of rRNA synthesis is brought about by the transcription initiation factor TIF-IA. TIF-IA is associated with a fraction of the TBP-containing factor TIF-IB/SL1 and the initiation-competent form of RNA polymerase I (Pol I). We investigated the mechanisms that down-regulate cellular pre-rRNA synthesis and demonstrate that nutrient starvation, density arrest and protein synthesis inhibitors inactivate TIF-IA and impair the association of TIF-IA with Pol I. Moreover, we used a panel of TIF-IA deletion mutants to map the domains that mediate the interaction of TIF-IA with Pol I and TIF-IB/SL1. We found that amino acids 512-609 interact with two subunits of Pol I, RPA43 and PAF67, whereas a short, conserved motif (LARAK, amino acids 411-415) is required for the association of TIF-IA with TAF(I)95 and TAF(I)68. The results uncover an interphase for essential protein-protein interactions that facilitate Pol I preinitiation complex formation.

Direct interaction of menin leads to ubiquitin-proteasomal degradation of β-catenin.

PubMed

Kim, Byungho; Song, Tae-Yang; Jung, Kwan Young; Kim, Seul Gi; Cho, Eun-Jung

2017-10-07

Menin, encoded by the multiple endocrine neoplasia type 1 (MEN1) gene, is a tumor suppressor and transcription regulator. Menin interacts with various proteins as a scaffold protein and is proposed to play important roles in multiple physiological and pathological processes by controlling gene expression, proliferation, and apoptosis. The mechanisms underlying menin's suppression of tumorigenesis are largely elusive. In this study, we showed that menin was essential for the regulation of canonical Wnt/β-catenin signaling in cultured cells. The C-terminal domain of menin was able to directly interact with and promote ubiquitin-mediated degradation of β-catenin. We further revealed that overexpression of menin down-regulated the transcriptional activity of β-catenin and target gene expression. Moreover, menin efficiently inhibited β-catenin protein levels, transcriptional activity, and proliferation of human renal carcinoma cells with an activated β-catenin pathway. Taken together, our results provide novel molecular insights into the tumor suppressor activity of menin, which is partly mediated by proteasomal degradation of β-catenin and inhibition of Wnt/β-catenin signaling. Copyright © 2017 Elsevier Inc. All rights reserved.

Steroid hormone induction of temporal gene expression in Drosophila brain neuroblasts generates neuronal and glial diversity

PubMed Central

Syed, Mubarak Hussain; Mark, Brandon; Doe, Chris Q

2017-01-01

An important question in neuroscience is how stem cells generate neuronal diversity. During Drosophila embryonic development, neural stem cells (neuroblasts) sequentially express transcription factors that generate neuronal diversity; regulation of the embryonic temporal transcription factor cascade is lineage-intrinsic. In contrast, larval neuroblasts generate longer ~50 division lineages, and currently only one mid-larval molecular transition is known: Chinmo/Imp/Lin-28+ neuroblasts transition to Syncrip+ neuroblasts. Here we show that the hormone ecdysone is required to down-regulate Chinmo/Imp and activate Syncrip, plus two late neuroblast factors, Broad and E93. We show that Seven-up triggers Chinmo/Imp to Syncrip/Broad/E93 transition by inducing expression of the Ecdysone receptor in mid-larval neuroblasts, rendering them competent to respond to the systemic hormone ecdysone. Importantly, late temporal gene expression is essential for proper neuronal and glial cell type specification. This is the first example of hormonal regulation of temporal factor expression in Drosophila embryonic or larval neural progenitors. DOI: http://dx.doi.org/10.7554/eLife.26287.001 PMID:28394252

Metformin suppresses CYP1A1 and CYP1B1 expression in breast cancer cells by down-regulating aryl hydrocarbon receptor expression

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

Do, Minh Truong; Kim, Hyung Gyun; Tran, Thi Thu Phuong

2014-10-01

Induction of cytochrome P450 (CYP) 1A1 and CYP1B1 by environmental xenobiotic chemicals or endogenous ligands through the activation of the aryl hydrocarbon receptor (AhR) has been implicated in a variety of cellular processes related to cancer, such as transformation and tumorigenesis. Here, we investigated the effects of the anti-diabetes drug metformin on expression of CYP1A1 and CYP1B1 in breast cancer cells under constitutive and inducible conditions. Our results indicated that metformin down-regulated the expression of CYP1A1 and CYP1B1 in breast cancer cells under constitutive and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced conditions. Down-regulation of AhR expression was required for metformin-mediated decreases in CYP1A1 andmore » CYP1B1 expression, and the metformin-mediated CYP1A1 and CYP1B1 reduction is irrelevant to estrogen receptor α (ERα) signaling. Furthermore, we found that metformin markedly down-regulated Sp1 protein levels in breast cancer cells. The use of genetic and pharmacological tools revealed that metformin-mediated down-regulation of AhR expression was mediated through the reduction of Sp1 protein. Metformin inhibited endogenous AhR ligand-induced CYP1A1 and CYP1B1 expression by suppressing tryptophan-2,3-dioxygenase (TDO) expression in MCF-7 cells. Finally, metformin inhibits TDO expression through a down-regulation of Sp1 and glucocorticoid receptor (GR) protein levels. Our findings demonstrate that metformin reduces CYP1A1 and CYP1B1 expression in breast cancer cells by down-regulating AhR signaling. Metformin would be able to act as a potential chemopreventive agent against CYP1A1 and CYP1B1-mediated carcinogenesis and development of cancer. - Graphical abstract: Schematic of the CYP1A1 and CYP1B1 gene regulation by metformin. - Highlights: • Metformin inhibits CYP1A1 and CYP1B1 expression. • Metformin down-regulates the AhR signaling. • Metformin reduces Sp1 protein expression. • Metformin suppresses TDO expression.« less

CCL5 promotes VEGF-dependent angiogenesis by down-regulating miR-200b through PI3K/Akt signaling pathway in human chondrosarcoma cells

PubMed Central

Liu, Guan-Ting; Chen, Hsien-Te; Tsou, Hsi-Kai; Tan, Tzu-Wei; Fong, Yi-Chin; Chen, Po-Chen; Yang, Wei-Hung; Wang, Shih-Wei; Chen, Jui-Chieh; Tang, Chih-Hsin

2014-01-01

Chondrosarcoma is the second most common primary malignant bone cancer, with potential for local invasion and distant metastasis. Chemokine CCL5 (formerly RANTES) of the CC-chemokine family plays a crucial role in metastasis. Angiogenesis is essential for the cancer metastasis. However, correlation of CCL5 with vascular endothelial growth factor (VEGF) expression and angiogenesis in human chondrosarcoma is still unknown. CCL5-mediated VEGF expression was assessed by qPCR, ELISA, and Western blotting. CCL5-induced angiogenesis was examined by migration and tube formation in endothelial progenitor cells in vitro. CCL5 increased VEGF expression and also promoted chondrosarcoma conditional medium-mediated angiogenesis in vitro and in vivo. Stimulation of chondrosarcoma with CCL5 augmented PI3K and Akt phosphorylation, while PI3K and Akt inhibitor or siRNA abolished CCL5-induced VEGF expression and angiogenesis. We also demonstrated CCL5 inhibiting miR-200b expression and miR-200b mimic reversing the CCL5-enhanced VEGF expression and angiogenesis. Moreover, in chondrosarcoma patients showed the positive correlation between CCL5 and VEGF; negative correlation between CCL5 and miR-200b. Taken together, results demonstrate CCL5 promoting VEGF-dependent angiogenesis in human chondrosarcoma cells by down-regulating miR-200b through PI3K/Akt signaling pathway. PMID:25301739

Sulforaphane induces neurovascular protection against a systemic inflammatory challenge via both Nrf2-dependent and independent pathways.

PubMed

Holloway, Paul M; Gillespie, Scarlett; Becker, Felix; Vital, Shantel A; Nguyen, Victoria; Alexander, J Steven; Evans, Paul C; Gavins, Felicity N E

2016-10-01

Sepsis is often characterized by an acute brain inflammation and dysfunction, which is associated with increased morbidity and mortality worldwide. Preventing cerebral leukocyte recruitment may provide the key to halt progression of systemic inflammation to the brain. Here we investigated the influence of the anti-inflammatory and anti-oxidant compound, sulforaphane (SFN) on lipopolysaccharide (LPS)-induced cellular interactions in the brain. The inflammatory response elicited by LPS was blunted by SFN administration (5 and 50mg/kg i.p.) 24h prior to LPS treatment in WT animals, as visualized and quantified using intravital microscopy. This protective effect of SFN was lost in Nrf2-KO mice at the lower dose tested, however 50mg/kg SFN revealed a partial effect, suggesting SFN works in part independently of Nrf2 activity. In vitro, SFN reduced neutrophil recruitment to human brain endothelial cells via a down regulation of E-selectin and vascular cell adhesion molecule 1 (VCAM-1). Our data confirm a fundamental dose-dependent role of SFN in limiting cerebral inflammation. Furthermore, our data demonstrate that not only is Nrf2 in part essential in mediating these neuroprotective effects, but they occur via down-regulation of E-selectin and VCAM-1. In conclusion, SFN may provide a useful therapeutic drug to reduce cerebral inflammation in sepsis. Copyright © 2016 Elsevier Inc. All rights reserved.

Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus Nsp4 Cleaves VISA to Impair Antiviral Responses Mediated by RIG-I-like Receptors

PubMed Central

Huang, Chen; Du, Yinping; Yu, Zhibin; Zhang, Qiong; Liu, Yihao; Tang, Jun; Shi, Jishu; Feng, Wen-hai

2016-01-01

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most significant etiological agents in the swine industry worldwide. It has been reported that PRRSV infection can modulate host immune responses, and innate immune evasion is thought to play a vital role in PRRSV pathogenesis. In this study, we demonstrated that highly pathogenic PRRSV (HP-PRRSV) infection specifically down-regulated virus-induced signaling adaptor (VISA), a unique adaptor molecule that is essential for retinoic acid induced gene-I (RIG-I) and melanoma differentiation associated gene 5 (MDA5) signal transduction. Moreover, we verified that nsp4 inhibited IRF3 activation induced by signaling molecules, including RIG-I, MDA5, VISA, and TBK1, but not IRF3. Subsequently, we demonstrated that HP-PRRSV nsp4 down-regulated VISA and suppressed type I IFN induction. Importantly, VISA was cleaved by nsp4 and released from mitochondrial membrane, which interrupted the downstream signaling of VISA. However, catalytically inactive mutant of nsp4 abolished its ability to cleave VISA. Interestingly, nsp4 of typical PRRSV strain CH-1a had no effect on VISA. Taken together, these findings reveal a strategy evolved by HP-PRRSV to counteract anti-viral innate immune signaling, which complements the known PRRSV-mediated immune-evasion mechanisms. PMID:27329948

CCAR1 is required for Ngn3-mediated endocrine differentiation

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

Lu, Chung-Kuang; Lai, Yi-Chyi; Lin, Yung-Fu

2012-02-10

Highlights: Black-Right-Pointing-Pointer We identify CCAR1 to directly interact with Ngn3. Black-Right-Pointing-Pointer CCAR1 is co-localized with Ngn3 in the nucleus. Black-Right-Pointing-Pointer CCAR1 cooperates with Ngn3 in activating NeuroD expression. Black-Right-Pointing-Pointer CCAR1 is required for Ngn3-mediated PANC-1 transdifferentiation. -- Abstract: Neurogenin3 (Ngn3) is a basic helix-loop-helix transcription factor that specifies pancreatic endocrine cell fates during pancreas development. It can also initiate a transdifferentiation program when expressed in pancreatic exocrine and ductal cells. However, how Ngn3 initiates a transcriptional cascade to achieve endocrine differentiation is still poorly understood. Here, we show that cell cycle and apoptosis regulator 1 (CCAR1), which is a transcriptionalmore » coactivator for nuclear receptors, also interacts with Ngn3. The association between Ngn3 and CCAR1 was verified by pull-down assays and co-immunoprecipitation analyses. Using gene reporter assays, we found that CCAR1 is essential for Ngn3 to activate the expression of the reporter genes containing the NeuroD promoter. Moreover, down-regulation of endogenous CCAR1 in the PANC-1 pancreatic ductal cell line inhibits the transdifferentiation program initiated by Ngn3. CCAR1 is, therefore, a novel partner of Ngn3 in mediating endocrine differentiation.« less

Data Normalization of (1)H NMR Metabolite Fingerprinting Data Sets in the Presence of Unbalanced Metabolite Regulation.

PubMed

Hochrein, Jochen; Zacharias, Helena U; Taruttis, Franziska; Samol, Claudia; Engelmann, Julia C; Spang, Rainer; Oefner, Peter J; Gronwald, Wolfram

2015-08-07

Data normalization is an essential step in NMR-based metabolomics. Conducted properly, it improves data quality and removes unwanted biases. The choice of the appropriate normalization method is critical and depends on the inherent properties of the data set in question. In particular, the presence of unbalanced metabolic regulation, where the different specimens and cohorts under investigation do not contain approximately equal shares of up- and down-regulated features, may strongly influence data normalization. Here, we demonstrate the suitability of the Shapiro-Wilk test to detect such unbalanced regulation. Next, employing a Latin-square design consisting of eight metabolites spiked into a urine specimen at eight different known concentrations, we show that commonly used normalization and scaling methods fail to retrieve true metabolite concentrations in the presence of increasing amounts of glucose added to simulate unbalanced regulation. However, by learning the normalization parameters on a subset of nonregulated features only, Linear Baseline Normalization, Probabilistic Quotient Normalization, and Variance Stabilization Normalization were found to account well for different dilutions of the samples without distorting the true spike-in levels even in the presence of marked unbalanced metabolic regulation. Finally, the methods described were applied successfully to a real world example of unbalanced regulation, namely, a set of plasma specimens collected from patients with and without acute kidney injury after cardiac surgery with cardiopulmonary bypass use.

21 CFR Appendix A to Subpart A of... - List of Applicable Laws, Regulations, and Administrative Provisions

Code of Federal Regulations, 2010 CFR

2010-04-01

... down by law, regulation, or administrative action relating to proprietary medicinal products as... provisions laid down by law, regulation or administrative action relating to proprietary medicinal products... approximation of the laws of the Member States relating to veterinary medicinal products, as widened and amended...

Down-regulation of cancer/testis antigen OY-TES-1 attenuates malignant behaviors of hepatocellular carcinoma cells in vitro.

PubMed

Fu, Jun; Luo, Bin; Guo, Wen-Wen; Zhang, Qing-Mei; Shi, Lei; Hu, Qi-Ping; Chen, Fang; Xiao, Shao-Wen; Xie, Xiao-Xun

2015-01-01

Cancer/testis (CT) antigens are normally expressed in testis and overexpressed in various tumor types. However, their biological function is largely unknown. OY-TES-1, one of cancer/testis (CT) antigens, is reported overexpression in hepatocellular carcinoma (HCC). And we assumed that OY-TES-1 contribute to oncogenesis and progression of HCC. In this study, we knocked down OY-TES-1 by small interference RNA (siRNA) in HCC cell lines (HepG2 and BEL-7404) to verify this assumption and evaluate its potential as therapeutic targets for HCC. We showed that down regulation of OY-TES-1 decreased cell growth, induced the G0/G1 arrest and apoptosis, and prevented migration and invasion in the two HCC cell lines. Further analysis revealed that down regulation of OY-TES-1 increased expression of apoptosis-regulated protein caspase-3, and decreased expression of cell cycle-regulated protein cyclin E, migration/invasion-regulated proteins MMP2 and MMP9. These findings may shed light on the gene therapy about the OY-TES-1 expression in HCC cells.

Down-regulation of cancer/testis antigen OY-TES-1 attenuates malignant behaviors of hepatocellular carcinoma cells in vitro

PubMed Central

Fu, Jun; Luo, Bin; Guo, Wen-Wen; Zhang, Qing-Mei; Shi, Lei; Hu, Qi-Ping; Chen, Fang; Xiao, Shao-Wen; Xie, Xiao-Xun

2015-01-01

Cancer/testis (CT) antigens are normally expressed in testis and overexpressed in various tumor types. However, their biological function is largely unknown. OY-TES-1, one of cancer/testis (CT) antigens, is reported overexpression in hepatocellular carcinoma (HCC). And we assumed that OY-TES-1 contribute to oncogenesis and progression of HCC. In this study, we knocked down OY-TES-1 by small interference RNA (siRNA) in HCC cell lines (HepG2 and BEL-7404) to verify this assumption and evaluate its potential as therapeutic targets for HCC. We showed that down regulation of OY-TES-1 decreased cell growth, induced the G0/G1 arrest and apoptosis, and prevented migration and invasion in the two HCC cell lines. Further analysis revealed that down regulation of OY-TES-1 increased expression of apoptosis-regulated protein caspase-3, and decreased expression of cell cycle-regulated protein cyclin E, migration/invasion-regulated proteins MMP2 and MMP9. These findings may shed light on the gene therapy about the OY-TES-1 expression in HCC cells. PMID:26339343

Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase pathway

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

Zhou, Xiuping, E-mail: xpzhou@xzmc.edu.cn; Lab of Neurosurgery, Xuzhou Medical College, Xuzhou, Jiangsu; Key Laboratory of Brain Disease Biology, Affiliated Hospital of Xuzhou Medical College, Jiangsu

Highlights: Black-Right-Pointing-Pointer The expression levels of Bex2 markedly increased in glioma tissues. Black-Right-Pointing-Pointer Bex2 over-expression promoted cell proliferation, while its down-regulation inhibited cell growth. Black-Right-Pointing-Pointer Bex2 down-regulation promoted cell apoptosis via JNK/c-Jun signaling pathway. -- Abstract: The function of Bex2, a member of the Brain Expressed X-linked gene family, in glioma is controversial and its mechanism is largely unknown. We report here that Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase (JNK) pathway. The expression level of Bex2 is markedly increased in glioma tissues. We observed that Bex2 over-expression promotes cell proliferation, whilemore » down-regulation of Bex2 inhibits cell growth. Furthermore, Bex2 down-regulation promotes cell apoptosis and activates the JNK pathway; these effects were abolished by administration of the JNK specific inhibitor, (SP600125). Thus, Bex2 may be an important player during the development of glioma.« less

CHIP mediates down-regulation of nucleobindin-1 in preosteoblast cell line models.

PubMed

Xue, Fuying; Wu, Yanping; Zhao, Xinghui; Zhao, Taoran; Meng, Ying; Zhao, Zhanzhong; Guo, Junwei; Chen, Wei

2016-08-01

Nucleobindin-1 (NUCB1), also known as Calnuc, is a highly conserved, multifunctional protein widely expressed in tissues and cells. It contains two EF-hand motifs which have been shown to play a crucial role in binding Ca(2+) ions. In this study, we applied comparative two-dimensional gel electrophoresis to characterize differentially expressed proteins in HA-CHIP over-expressed and endogenous CHIP depleted MC3T3-E1 stable cell lines, identifying NUCB1 as a novel CHIP/Stub1 targeted protein. NUCB1 interacts with and is down-regulated by CHIP by both proteasomal dependent and independent pathways, suggesting that CHIP-mediated down-regulation of nucleobindin-1 might play a role in osteoblast differentiation. The chaperone protein Hsp70 was found to be important for CHIP and NUCB1 interaction as well as CHIP-mediated NUCB1 down-regulation. Our findings provide new insights into understanding the stability regulation of NUCB1. Copyright © 2016 Elsevier Inc. All rights reserved.

Essential oils from Inula japonica and Angelicae dahuricae enhance sensitivity of MCF-7/ADR breast cancer cells to doxorubicin via multiple mechanisms.

PubMed

Wu, Min; Li, Tingting; Chen, Lilan; Peng, Sugang; Liao, Wei; Bai, Ruolan; Zhao, Xue; Yang, Hong; Wu, Chunhui; Zeng, Hongjuan; Liu, Yiyao

2016-03-02

Angelicae dahurica (Hoffm.) Benth. & Hook.f.ex Franch. & Sav combined with Pueraria and Gastrodia elata Bl. combined with Inula japonica Thunb. are widely used in herb-pairs of traditional chinese medicine. Previous studies have shown that Angelicae dahuricae essential oil (ADO) enhanced puerarin internalization into ABCB1-overexpressed Caco-2 cells. These findings suggest the possibility that essential oils may enhance the absorption via certain mechanisms related to ABCB1 and reverse multidrug resistance (MDR). ADO and essential oils from Inula japonica (IJO) may reverse ABCB1-mediated MDR, but this ability has not been investigated in detail in the well-established cancer cell lines. In this study, the underlying molecular mechanisms were further investigated to examine how IJO and ADO reverse MDR in the resistant human breast cancer cell line of MCF-7/ADR. Also this work may help uncover the conceivable compatibility mechanisms of above herb-pairs involved in ABCB1. The MDR human breast cancer MCF-7/ADR cells were treated with IJO, its sesquiterpene component isoalantolactone (ISO) or ADOat non- cytotoxic concentrations. The MDR ability was examined by measuring the sensitivity to doxorubicin (DOX), DOX accumulation and efflux, ABCB1 ATPase activity, ABCB1 expression, membrane fluidity, and stability and localization of lipid rafts and caveolae. Finally, the molecular modeling was performed to postulate how ISO interacts with ABCB1. Treating MCF-7/ADR cells with IJ oil, ISO or AD oil reversed MDR 2- to 3-fold, without affecting the sensitivity of the non-MDR parental cell line. Mechanistic studies showed that these oils down-regulated mRNA and protein expression of ABCB1, and reduced the stability of lipid rafts in the cell membrane, which has previously been shown to reduce ABCB1-mediated transport. On the other hand, IJO, ISO and ADO did not inhibit ABCB1 ATPase activity, and fluorescence polarization experiments showed that low concentrations of the oils did not appear to alter membrane fluidity, unlike some MDR-reversing agents, ISO showed a higher docking score than verapamil but lower than dofequidar and tariquidar. Our results suggest that IJO, ISO and ADO could reverse MDR by down-regulating ABCB1 expression and reducing lipid raft stability. These findings may be useful for developing safer and effective MDR reversal agents and also help find out the compatibility mechanisms. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Attenuation of PAMP-triggered immunity in maize requires down-regulation of the key β-1,6-glucan synthesis genes KRE5 and KRE6 in biotrophic hyphae of Colletotrichum graminicola.

PubMed

Oliveira-Garcia, Ely; Deising, Holger B

2016-08-01

In plants, pathogen defense is initiated by recognition of pathogen-associated molecular patterns (PAMPs) via plasma membrane-localized pattern-recognition receptors (PRRs). Fungal structural cell wall polymers such as branched β-glucans are essential for infection structure rigidity and pathogenicity, but at the same time represent PAMPs. Kre5 and Kre6 are key enzymes in β-1,6-glucan synthesis and formation of branch points of the β-glucan network. In spite of the importance of branched β-glucan for hyphal rigidity and plant-fungus interactions, neither the role of KRE5 and KRE6 in pathogenesis nor mechanisms allowing circumventing branched β-glucan-triggered immune responses are known. We functionally characterized KRE5 and KRE6 of the ascomycete Colletotrichum graminicola, a hemibiotroph that infects maize (Zea mays). After appressorial plant invasion, this fungus sequentially differentiates biotrophic and highly destructive necrotrophic hyphae. RNAi-mediated reduction of KRE5 and KRE6 transcript abundance caused appressoria to burst and swelling of necrotrophic hyphae, indicating that β-1,6-glucosidic bonds are essential in these cells. Live cell imaging employing KRE5:mCherry and KRE6:mCherry knock-in strains and probing of infection structures with a YFP-conjugated β-1,6-glucan-binding protein showed expression of these genes and exposure of β-1,6-glucan in conidia, appressoria and necrotrophic, but not in biotrophic hyphae. Overexpression of KRE5 and KRE6 in biotrophic hyphae led to activation of broad-spectrum plant defense responses, including papilla and H2 O2 formation, as well as transcriptional activation of several defense-related genes. Collectively, our results strongly suggest that down-regulation of synthesis and avoidance of exposure of branched β-1,3-β-1,6-glucan in biotrophic hyphae is required for attenuation of plant immune responses. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

Phytochemical regulation of the tumor suppressive microRNA, miR-34a, by p53-dependent and independent responses in human breast cancer cells

PubMed Central

Hargraves, Kris G.; He, Lin; Firestone, Gary L.

2016-01-01

The tumor suppressive microRNA miR-34a is transcriptionally regulated by p53 and shown to inhibit breast cancer cell proliferation as well as being a marker of increased disease free survival. Indole-3-carbinol (I3C) derived from cruciferous vegetables, artemisinin, extracted from the sweet wormwood plant, and artesunate, a semi-synthetic derivative of artemisinin, are phytochemicals with anti-tumorigenic properties however, little is known about the role of microRNAs in their mechanism of action. Human breast cancer cells expressing wild-type (MCF-7) or mutant p53 (T47D) were treated with a concentration range and time course of each phytochemical under conditions of cell cycle arrest as detected by flow cytometry to examine the potential connection between miR-34a expression and their anti-proliferative responses. Real-time PCR and western blot analysis of extracted RNA and total protein revealed artemsinin and artesunate increased miR-34a expression in a dose-dependent manner correlating with down-regulation of the miR-34a target gene, CDK4. I3C stimulation of miR-34a expression required functional p53, whereas, both artemisinin and artesunate up-regulated miR-34a expression regardless of p53 mutational status or in the presence of dominant negative p53. Phytochemical treatments inhibited the luciferase activity of a construct containing the wild-type 3′UTR of CDK4, but not those with a mutated miR-34a binding site, whereas, transfection of miR-34a inhibitors ablated the phytochemical mediated down-regulation of CDK4 and induction of cell cycle arrest. Our results suggest that miR-34a is an essential component of the anti-proliferative activities of I3C, artemisinin and artesunate and demonstrate that both wild-type p53 dependent and independent pathways are responsible for miR-34a induction. PMID:25789847

Resveratrol downregulates inflammatory pathway activated by lymphotoxin α (TNF-β) in articular chondrocytes: Comparison with TNF-α

PubMed Central

Buhrmann, Constanze; Popper, Bastian; Aggarwal, Bharat B.

2017-01-01

While Lymphotoxin α (TNF-β), a product of lymphocytes, is known to play a pivotal role in inflammatory joint environment, resveratrol has been shown to possess anti-inflammatory and chondroprotective effects via activation of the histondeacetylase Sirt1. Whether TNF-β induction of inflammatory pathways in primary human chondrocytes (PCH) can be modulated by resveratrol, was investigated. Monolayer and alginate cultures of PCH were treated with TNF-β, anti-TNF-β, nicotinamide (NAM), antisense oligonucleotides against Sirt1 (Sirt1-ASO) and/or resveratrol and co-cultured with T-lymphocytes. We found that resveratrol suppressed, similar to anti-TNF-β, TNF-β-induced increased adhesiveness in an inflammatory microenvironment of T-lymphocytes and PCH. In contrast, knockdown of Sirt1 by mRNA abolished the inhibitory effects of resveratrol on the TNF-β-induced adhesiveness, suggesting the essential role of this enzyme for resveratrol-mediated anti-inflammatory signaling. Similar results were obtained in PCH stimulated with TNF-α. Sirt1-ASO, NAM or TNF-β, similar to T-lymphocytes induced inflammatory microenvironment by down-regulation of cartilage-specific proteins, Sox9, Ki67 and enhanced NF-κB-regulated gene products involved in inflammatory and degradative processes in cartilage (MMP-9/-13, COX-2, caspase-3), NF-κB activation and its translocation to the nucleus. Moreover, resveratrol reversed the TNF-β-, NAM-, T-lymphocytes-induced up-regulation of various NF-κB-regulated gene products. Down-regulation of Sirt1 by mRNA interference abrogated the effect of resveratrol on TNF-β-induced effects. Ultrastructural and cell viability assay investigations revealed that resveratrol revoked TNF-β-induced dose-dependent degradative/apoptotic morphological changes, cell viability and proliferation in PCH. Taken together, suppression of TNF-β-induced inflammatory microenvironment in PCH by resveratrol/Sirt1 might be a novel therapeutic approach for targeting inflammation during rheumatoid arthritis. PMID:29095837

A Study of Early Fine Motor Intervention in Down's Syndrome Children

ERIC Educational Resources Information Center

Aparicio, Teresa Sanz; Balana, Javier Menendez

2009-01-01

The marked delay in acquisition of fine motor skills in trisomic-21/Down's syndrome children is undeniable. In this study, we began with an affirmation that the cause of this deficit could be found in a different environment for which early intervention is essential. A sample of 30 Down's syndrome children was used to study at different ages: six…

Absence of Nucleotide-Oligomerization-Domain-2 Is Associated with Less Distinct Disease in Campylobacter jejuni Infected Secondary Abiotic IL-10 Deficient Mice.

PubMed

Heimesaat, Markus M; Grundmann, Ursula; Alutis, Marie E; Fischer, André; Bereswill, Stefan

2017-01-01

Human Campylobacter jejuni -infections are progressively increasing worldwide. Despite their high prevalence and socioeconomic impact the underlying mechanisms of pathogen-host-interactions are only incompletely understood. Given that the innate immune receptor nucleotide-oligomerization-domain-2 (Nod2) is involved in clearance of enteropathogens, we here evaluated its role in murine campylobacteriosis. To address this, we applied Nod2-deficient IL-10 -/- (Nod2 -/- IL-10 -/- ) mice and IL-10 -/- counterparts both with a depleted intestinal microbiota to warrant pathogen-induced enterocolitis. At day 7 following peroral C. jejuni strain 81-176 infection, Nod2 mRNA was down-regulated in the colon of secondary abiotic IL-10 -/- and wildtype mice. Nod2-deficiency did neither affect gastrointestinal colonization nor extra-intestinal and systemic translocation properties of C. jejuni . Colonic mucin-2 mRNA was, however, down-regulated upon C. jejuni -infection of both Nod2 -/- IL-10 -/- and IL-10 -/- mice, whereas expression levels were lower in infected, but also naive Nod2 -/- IL-10 -/- mice as compared to respective IL-10 -/- controls. Remarkably, C. jejuni -infected Nod2 -/- IL-10 -/- mice were less compromised than IL-10 -/- counterparts and displayed less distinct apoptotic, but higher regenerative cell responses in colonic epithelia. Conversely, innate as well as adaptive immune cells such as macrophages and monocytes as well as T lymphocytes and regulatory T-cells, respectively, were even more abundant in large intestines of Nod2 -/- IL-10 -/- as compared to IL-10 -/- mice at day 7 post-infection. Furthermore, IFN-γ concentrations were higher in ex vivo biopsies derived from intestinal compartments including colon and mesenteric lymph nodes as well as in systemic tissue sites such as the spleen of C. jejuni infected Nod2 -/- IL-10 -/- as compared to IL10 -/- counterparts. Whereas, at day 7 postinfection anti-inflammatory IL-22 mRNA levels were up-regulated, IL-18 mRNA was down-regulated in large intestines of Nod2 -/- IL-10 -/- vs. IL-10 -/- mice. In summary, C. jejuni -infection induced less clinical signs and apoptosis, but more distinct colonic pro- and (of note) anti-inflammatory immune as well as regenerative cell responses in Nod2 deficient IL-10 -/- as compared to IL-10 -/- control mice. We conclude that, even though colonic Nod2 mRNA was down-regulated upon pathogenic challenge, Nod2-signaling is essentially involved in the well-balanced innate and adaptive immune responses upon C. jejuni -infection of secondary abiotic IL-10 -/- mice, but does neither impact pathogenic colonization nor translocation.

Characterization of Changes in Global Genes Expression in the Distal Colon of Loperamide-Induced Constipation SD Rats in Response to the Laxative Effects of Liriope platyphylla

PubMed Central

Kim, Ji Eun; Park, So Hae; Kwak, Moon Hwa; Go, Jun; Koh, Eun Kyoung; Song, Sung Hwa; Sung, Ji Eun; Lee, Hee Seob; Hong, Jin Tae; Hwang, Dae Youn

2015-01-01

To characterize the changes in global gene expression in the distal colon of constipated SD rats in response to the laxative effects of aqueous extracts of Liriope platyphylla (AEtLP), including isoflavone, saponin, oligosaccharide, succinic acid and hydroxyproline, the total RNA extracted from the distal colon of AEtLP-treated constipation rats was hybridized to oligonucleotide microarrays. The AEtLP treated rats showed an increase in the number of stools, mucosa thickness, flat luminal surface thickness, mucin secretion, and crypt number. Overall, compared to the controls, 581 genes were up-regulated and 216 genes were down-regulated by the constipation induced by loperamide in the constipated rats. After the AEtLP treatment, 67 genes were up-regulated and 421 genes were down-regulated. Among the transcripts up-regulated by constipation, 89 were significantly down-regulated and 22 were recovered to the normal levels by the AEtLP treatment. The major genes in the down-regulated categories included Slc9a5, klk10, Fgf15, and Alpi, whereas the major genes in the recovered categories were Cyp2b2, Ace, G6pc, and Setbp1. On the other hand, after the AEtLP treatment, ten of these genes down-regulated by constipation were up-regulated significantly and five were recovered to the normal levels. The major genes in the up-regulated categories included Serpina3n, Lcn2 and Slc5a8, whereas the major genes in the recovered categories were Tmem45a, Rerg and Rgc32. These results indicate that several gene functional groups and individual genes as constipation biomarkers respond to an AEtLP treatment in constipated model rats. PMID:26151867

Conditional ablation of the Notch2 receptor in the ocular lens

PubMed Central

Saravanamuthu, Senthil S.; Le, Tien T.; Gao, Chun Y.; Cojocaru, Radu I.; Pandiyan, Pushpa; Liu, Chunqiao; Zhang, Jun; Zelenka, Peggy S.; Brown, Nadean L.

2011-01-01

Notch signaling is essential for proper lens development, however the specific requirements of individual Notch receptors have not been investigated. Here we report the lens phenotypes of Notch2 conditionally mutant mice, which exhibited severe microphthalmia, reduced pupillary openings, disrupted fiber cell morphology, eventual loss of the anterior epithelium, fiber cell dysgenesis, denucleation defects, and cataracts. Notch2 mutants also had persistent lens stalks as early as E11.5, and aberrant DNA synthesis in the fiber cell compartment by E14.5. Gene expression analyses showed that upon loss of Notch2, there were elevated levels of the cell cycle regulators Cdkn1a (p21Cip1), Ccnd2 (CyclinD2), and Trp63 (p63) that negatively regulates Wnt signaling, plus down-regulation of Cdh1 (E-Cadherin). Removal of Notch2 also resulted in an increased proportion of fiber cells, as was found in Rbpj and Jag1 conditional mutant lenses. However, Notch2 is not required for AEL proliferation, suggesting that a different receptor regulates this process. We found that Notch2 normally blocks lens progenitor cell death. Overall, we conclude that Notch2-mediated signaling regulates lens morphogenesis, apoptosis, cell cycle withdrawal, and secondary fiber cell differentiation. PMID:22173065

Glucose Modulates Respiratory Complex I Activity in Response to Acute Mitochondrial Dysfunction

PubMed Central

Cannino, Giuseppe; El-Khoury, Riyad; Pirinen, Marja; Hutz, Bettina; Rustin, Pierre; Jacobs, Howard T.; Dufour, Eric

2012-01-01

Proper coordination between glycolysis and respiration is essential, yet the regulatory mechanisms involved in sensing respiratory chain defects and modifying mitochondrial functions accordingly are unclear. To investigate the nature of this regulation, we introduced respiratory bypass enzymes into cultured human (HEK293T) cells and studied mitochondrial responses to respiratory chain inhibition. In the absence of respiratory chain inhibitors, the expression of alternative respiratory enzymes did not detectably alter cell physiology or mitochondrial function. However, in permeabilized cells NDI1 (alternative NADH dehydrogenase) bypassed complex I inhibition, whereas alternative oxidase (AOX) bypassed complex III or IV inhibition. In contrast, in intact cells the effects of the AOX bypass were suppressed by growth on glucose, whereas those produced by NDI1 were unaffected. Moreover, NDI1 abolished the glucose suppression of AOX-driven respiration, implicating complex I as the target of this regulation. Rapid Complex I down-regulation was partly released upon prolonged respiratory inhibition, suggesting that it provides an “emergency shutdown” system to regulate metabolism in response to dysfunctions of the oxidative phosphorylation. This system was independent of HIF1, mitochondrial superoxide, or ATP synthase regulation. Our findings reveal a novel pathway for adaptation to mitochondrial dysfunction and could provide new opportunities for combatting diseases. PMID:23007390

Chromatin-remodeling SWI/SNF complex regulates coenzyme Q6 synthesis and a metabolic shift to respiration in yeast.

PubMed

Awad, Agape M; Venkataramanan, Srivats; Nag, Anish; Galivanche, Anoop Raj; Bradley, Michelle C; Neves, Lauren T; Douglass, Stephen; Clarke, Catherine F; Johnson, Tracy L

2017-09-08

Despite its relatively streamlined genome, there are many important examples of regulated RNA splicing in Saccharomyces cerevisiae Here, we report a role for the chromatin remodeler SWI/SNF in respiration, partially via the regulation of splicing. We find that a nutrient-dependent decrease in Snf2 leads to an increase in splicing of the PTC7 transcript. The spliced PTC7 transcript encodes a mitochondrial phosphatase regulator of biosynthesis of coenzyme Q 6 (ubiquinone or CoQ 6 ) and a mitochondrial redox-active lipid essential for electron and proton transport in respiration. Increased splicing of PTC7 increases CoQ 6 levels. The increase in PTC7 splicing occurs at least in part due to down-regulation of ribosomal protein gene expression, leading to the redistribution of spliceosomes from this abundant class of intron-containing RNAs to otherwise poorly spliced transcripts. In contrast, a protein encoded by the nonspliced isoform of PTC7 represses CoQ 6 biosynthesis. Taken together, these findings uncover a link between Snf2 expression and the splicing of PTC7 and establish a previously unknown role for the SWI/SNF complex in the transition of yeast cells from fermentative to respiratory modes of metabolism. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

A top-down perspective on dopamine, motivation and memory.

PubMed

Phillips, Anthony G; Vacca, Giada; Ahn, Soyon

2008-08-01

Dopamine (DA) activity, in the form of increased neural firing or enhanced release of transmitter from nerve terminals and varicosities, is linked to a number of important psychological processes including: movement; hedonic reactions to positive reward; provision of an error detection signal during the acquisition of new learning; response to novel stimuli; provision of reinforcement signals essential for acquisition of new action patterns; and incentive motivation. This review focuses primarily on our research linking dynamic changes in DA efflux on the timescale of minutes, with incentive motivation, as revealed by brain dialysis experiments in behaving animals. Recent experiments on sensory-specific satiety and successive positive and negative contrast are discussed along with the distinction between preparatory behaviors that precede contact with biologically significant stimuli and subsequent consummatory behaviors. The relationship between DA efflux in the medial prefrontal cortex (mPFC) and foraging for food based on working memory is also discussed in support of the conjecture that DA may serve as a link between motivation and memory functions. Evidence in support of 'top-down' regulation of dopaminergic activity in the mesocorticolimbic DA pathways is reviewed briefly to introduce a mechanism by which activation of ascending DA projections in this manner might optimize dopaminergic modulation of executive function within regions such as the mPFC. Collectively, these processes could ensure coordination between cognitive processes that assess current opportunities and the motivational systems that select and engage patterns of approach behavior that bring organisms into contact with the essentials for survival.

[Parvovirus B19 infection as the cause of hepatitis and neutrophil granulocytosis in a 20-year old woman].

PubMed

Wiggers, H; Rasmussen, L H; Møller, A

1995-10-23

A case of Parvovirus B19 infection (erythema infectiosum) in a 20 year old woman is presented. The patient presented with fever, arthritis in one knee, neutrophil granulocytosis and biochemical evidence of hepatitis. Serological evidence of Parvovirus B19 infection was found as the only explanation of the clinical picture. Hepatitis was due to Parvovirus B19 infection as there was no serological evidence of EBV or CMV reactivation. Neutrophil granulocytosis and thrombocytosis were found and were probably due to an active bone marrow in the recovery phase of bone marrow aplasia.

Beta-thalassemia intermedia associated with moyamoya syndrome.

PubMed

Göksel, Basak Karakurum; Ozdogu, Hakan; Yildirim, Tulin; Oğuzkurt, Levent; Asma, Suheyl

2010-07-01

Moyamoya syndrome (MMS) is a progressive disorder. We report a 19-year-old boy with beta-thalassemia who presented with a left hemiparesis. Brain MRI showed old middle cerebral artery and left frontal subcortical white matter infarcts. Brain magnetic resonance angiography and digital subtraction angiography revealed occlusion of the bilateral internal carotid arteries with a rich network of basal collateral vessels. To our knowledge this is the third report of beta-thalassemia intermedia and MMS, and the first report of a patient in Turkey. It emphasizes the potential for cerebral infarct due to anemia, protein S and thrombocytosis.

Anterior segment dysgenesis correlation with epithelial-mesenchymal transition in Smad4 knockout mice.

PubMed

Li, Jing; Qin, Yu; Zhao, Fang-Kun; Wu, Di; He, Xue-Fei; Liu, Jia; Zhao, Jiang-Yue; Zhang, Jin-Song

2016-01-01

To explore the molecular mechanisms in lens development and the pathogenesis of Peters anomaly in Smad4 defective mice. Le-Cre transgenic mouse line was employed to inactivate Smad4 in the surface ectoderm selectively. Pathological techniques were used to reveal the morphological changes of the anterior segment in Smad4 defective eye. Immunohistochemical staining was employed to observe the expression of E-cadherin, N-cadherin and α-SMA in anterior segment of Smad4 defective mice and control mice at embryonic (E) day 16.5. Real-time quantitative polymerase chain reaction (qPCR) was performed to detect the expression of Snail, Zeb1, Zeb2 and Twist2 in lens of Smad4 defective mice and control mice at E16.5. Statistical evaluations were performed using the unpaired Student's t-test (two-tailed) by SPSS 11.0 software. Conditional deletion of Smad4 on eye surface ectoderm resulted in corneal dysplasia, iridocorneal angle closure, corneolenticular adhesions and cataract resembling Peters anomaly. Loss of Smad4 function inhibited E-cadherin expression in the lens epithelium cells and corneal epithelium cells in Smad4 defective eye. Expression of N-cadherin was up-regulated in corneal epithelium and corneal stroma. Both E-cadherin and N-cadherin were down-regulated at the future trabecular meshwork region in mutant eye. The qPCR results showed that the expression of Twist2 was increased significantly in the mutant lens (P<0.01). Smad4 is essential to eye development and likely a candidate pathogenic gene to Peters anomaly by regulating epithelial-mesenchymal transition. Twist2 can be regulated by Smad4 and plays an essential role in lens development.

Down-regulated peroxisome proliferator-activated receptor γ (PPARγ) in lung epithelial cells promotes a PPARγ agonist-reversible proinflammatory phenotype in chronic obstructive pulmonary disease (COPD).

PubMed

Lakshmi, Sowmya P; Reddy, Aravind T; Zhang, Yingze; Sciurba, Frank C; Mallampalli, Rama K; Duncan, Steven R; Reddy, Raju C

2014-03-07

Chronic obstructive pulmonary disease (COPD) is a progressive inflammatory condition and a leading cause of death, with no available cure. We assessed the actions in pulmonary epithelial cells of peroxisome proliferator-activated receptor γ (PPARγ), a nuclear hormone receptor with anti-inflammatory effects, whose role in COPD is largely unknown. We found that PPARγ was down-regulated in lung tissue and epithelial cells of COPD patients, via both reduced expression and phosphorylation-mediated inhibition, whereas pro-inflammatory nuclear factor-κB (NF-κB) activity was increased. Cigarette smoking is the main risk factor for COPD, and exposing airway epithelial cells to cigarette smoke extract (CSE) likewise down-regulated PPARγ and activated NF-κB. CSE also down-regulated and post-translationally inhibited the glucocorticoid receptor (GR-α) and histone deacetylase 2 (HDAC2), a corepressor important for glucocorticoid action and whose down-regulation is thought to cause glucocorticoid insensitivity in COPD. Treating epithelial cells with synthetic (rosiglitazone) or endogenous (10-nitro-oleic acid) PPARγ agonists strongly up-regulated PPARγ expression and activity, suppressed CSE-induced production and secretion of inflammatory cytokines, and reversed its activation of NF-κB by inhibiting the IκB kinase pathway and by promoting direct inhibitory binding of PPARγ to NF-κB. In contrast, PPARγ knockdown via siRNA augmented CSE-induced chemokine release and decreases in HDAC activity, suggesting a potential anti-inflammatory role of endogenous PPARγ. The results imply that down-regulation of pulmonary epithelial PPARγ by cigarette smoke promotes inflammatory pathways and diminishes glucocorticoid responsiveness, thereby contributing to COPD pathogenesis, and further suggest that PPARγ agonists may be useful for COPD treatment.

Down-regulation of Wnt10a affects odontogenesis and proliferation in mesenchymal cells

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

Liu, Yang, E-mail: Ly10160624@163.com; Han, Dong, E-mail: Donghan@bjmu.edu.cn; Wang, Lei, E-mail: wanglei_dentist@163.com

Highlights: •Down-regulation of Wnt10a in dental mesenchymal cells impairs odontogenesis of reassociated tooth germs. •Dspp is down- and up-regulated after Wnt10a-knockdown and overexpression in dental mesenchymal cells. •Down-regulation of Wnt10a inhibits proliferation of dental mesenchymal cells. -- Abstract: The WNT10a mutation has been found in patients with abnormal odontogenesis. In mice, Wnt10a expression is found in the tooth germ, but its role has not yet been elucidated. We aimed to investigate the role of Wnt10a in odontogenesis. Mesenchymal cells of the first mandibular molar germ at the bell stage were isolated, transfected with Wnt10a SiRNA or plasmid, and reassociated withmore » epithelial part of the molar germ. Scrambled SiRNA or empty vector was used in the control group. The reassociated tooth germs were transplanted into mice subrenal capsules. After gene modification, dental mesenchymal cells cultured in vitro were checked for cell proliferation and the expression of Dspp was examined. All 12 reassociated tooth germs in the control group resumed odontogenesis, while only 5 of 12 in the Wnt10a knockdown group developed into teeth. After Wnt10a knockdown, the mesenchymal cells cultured in vitro presented repressed proliferation. Wnt10a knockdown and overexpression led to both down- and up-regulation of Dspp. We conclude that the down-regulation of Wnt10a impairs odontogensis and cell proliferation, and that Wnt10a regulates Dspp expression in mesenchymal cells. These findings help to elucidate the mechanism of abnormal tooth development in patients with the WNT10A mutation.« less

Transcription of G-protein coupled receptors in corporal smooth muscle is regulated by sialorphin (an endogenous neutral endopeptidase inhibitor)

PubMed Central

Tong, Yuehong; Tiplitsky, Scott I.; Tar, Moses; Melman, Arnold; Davies, Kelvin P.

2009-01-01

Purpose Several reports have suggested the rat Vcsa1 gene is down-regulated in models of erectile dysfunction (ED). Vcsa’s protein product, sialorphin, is an endogenous neutral endopeptidase (NEP), and its down-regulation could result in prolonged activation of G-protein activated signaling pathways by their peptide agonists. We investigated if down- regulation of Vcsa1 could result in adaptive change in the expression of G-protein coupled receptors (GPCR). Materials and Methods Gene expression in cultured rat corporal smooth muscle cells (CSM) following treatment with siRNA directed against Vcsa1 or the NEP gene was analyzed using microarray and quantitative RT-PCR. In rats Vcsa1 is one of the most down-regulated genes following bilateral transection of the cavernosal nerves. Using that animal model, we also investigated whether the down-regulation of Vcsa1 is accompanied by similar changes in gene expression observed in the CSM cells where Vcsa1 was knocked-down in vitro. Results Microarray analysis and quantitative RT-PCR demonstrated that CSM cells treated in vitro with siRNA against Vcsa1 resulted in up-regulation of GPCR as a functional group. In contrast, treatment of CSM cells that lowered NEP activity resulted in decreases in GPCR expression. These results suggest that the peptide product of Vcsa1, sialorphin, can effect GPCR expression by acting on NEP. In animals with bilaterally transected cavernous nerves the reduced expression of Vcsa1 is accompanied by increased GPCR expression in cavernosal tissue. Conclusions These experiments suggest that the mechanism by which Vcsa1 modulates erectile function is partly mediated through changes in GPCR expression. PMID:18554633

Transcription of G-protein coupled receptors in corporeal smooth muscle is regulated by the endogenous neutral endopeptidase inhibitor sialorphin.

PubMed

Tong, Yuehong; Tiplitsky, Scott I; Tar, Moses; Melman, Arnold; Davies, Kelvin P

2008-08-01

Several reports suggest that the rat Vcsa1 gene is down-regulated in models of erectile dysfunction. The Vcsa protein product sialorphin is an endogenous neutral endopeptidase inhibitor and its down-regulation could result in prolonged activation of G-protein activated signaling pathways by their peptide agonists. We investigated whether Vcsa1 down-regulation could result in an adaptive change in GPCR (G-protein coupled receptor) expression. Gene expression in cultured rat corporeal smooth muscle cells following treatment with siRNA directed against Vcsa1 or the neutral endopeptidase gene was analyzed using microarray and quantitative reverse transcriptase-polymerase chain reaction. In rats Vcsa1 is one of the most down-regulated genes following bilateral transection of the cavernous nerves. In that animal model we also investigated whether Vcsa1 down-regulation was accompanied by similar changes in gene expression in corporeal smooth muscle cells in which Vcsa1 was knocked down in vitro. Microarray analysis and quantitative reverse transcriptase-polymerase chain reaction demonstrated that corporeal smooth muscle cells treated in vitro with siRNA against Vcsa1 resulted in GPCR up-regulation as a functional group. In contrast, treatment of corporeal smooth muscle cells that lowered neutral endopeptidase activity resulted in decreased GPCR expression. These results suggest that the peptide product of Vcsa1, sialorphin, can effect GPCR expression by acting on neutral endopeptidase. In animals with bilaterally transected cavernous nerves the decreased Vcsa1 expression is accompanied by increased GPCR expression in cavernous tissue. These experiments suggest that the mechanism by which Vcsa1 modulates erectile function is partly mediated through changes in GPCR expression.

Modulation of HIV replication in monocyte derived macrophages (MDM) by steroid hormones.

PubMed

Devadas, Krishnakumar; Biswas, Santanu; Ragupathy, Viswanath; Lee, Sherwin; Dayton, Andrew; Hewlett, Indira

2018-01-01

Significant sex specific differences in the progression of HIV/AIDS have been reported. Several studies have implicated steroid hormones in regulating host factor expression and modulating HIV transmission and replication. However, the exact mechanism exerted by steroid hormones estrogen and progesterone in the regulation of HIV-1 replication is still unclear. Results from the current study indicated a dose dependent down regulation of HIV-1 replication in monocyte derived macrophages pre-treated with high concentrations of estrogen or progesterone. To elucidate the molecular mechanisms associated with the down regulation of HIV-1 replication by estrogen and progesterone we used PCR arrays to analyze the expression profile of host genes involved in antiviral responses. Several chemokines, cytokines, transcription factors, interferon stimulated genes and genes involved in type-1 interferon signaling were down regulated in cells infected with HIV-1 pre-treated with high concentrations of estrogen or progesterone compared to untreated HIV-1 infected cells or HIV-1 infected cells treated with low concentrations of estrogen or progesterone. The down regulation of CXCL9, CXCL10 and CXCL11 chemokines and IL-1β, IL-6 cytokines in response to high concentrations of estrogen and progesterone pre-treatment in HIV-1 infected cells was confirmed at the protein level by quantitating chemokine and cytokine concentrations in the culture supernatant. These results demonstrate that a potent anti-inflammatory response is mediated by pre-treatment with high concentrations of estrogen and progesterone. Thus, our study suggests a strong correlation between the down-modulation of anti-viral and pro-inflammatory responses mediated by estrogen and progesterone pre-treatment and the down regulation of HIV-1 replication. These findings may be relevant to clinical observations of sex specific differences in patient populations and point to the need for further investigation.

Drought-Up-Regulated TaNAC69-1 is a Transcriptional Repressor of TaSHY2 and TaIAA7, and Enhances Root Length and Biomass in Wheat.

PubMed

Chen, Dandan; Richardson, Terese; Chai, Shoucheng; Lynne McIntyre, C; Rae, Anne L; Xue, Gang-Ping

2016-10-01

A well-known physiological adaptation process of plants encountering drying soil is to achieve water balance by reducing shoot growth and maintaining or promoting root elongation, but little is known about the molecular basis of this process. This study investigated the role of a drought-up-regulated Triticum aestivum NAC69-1 (TaNAC69-1) in the modulation of root growth in wheat. TaNAC69-1 was predominantly expressed in wheat roots at the early vegetative stage. Overexpression of TaNAC69-1 in wheat roots using OsRSP3 (essentially root-specific) and OsPIP2;3 (root-predominant) promoters resulted in enhanced primary seminal root length and a marked increase in maturity root biomass. Competitive growth analysis under water-limited conditions showed that OsRSP3 promoter-driven TaNAC69-1 transgenic lines produced 32% and 35% more above-ground biomass and grains than wild-type plants, respectively. TaNAC69-1 overexpression in the roots down-regulated the expression of TaSHY2 and TaIAA7, which are from the auxin/IAA (Aux/IAA) transcriptional repressor gene family and are the homologs of negative root growth regulators SHY2/IAA3 and IAA7 in Arabidopsis. The expression of TaSHY2 and TaIAA7 in roots was down-regulated by drought stress and up-regulated by cytokinin treatment, which inhibited root growth. DNA binding and transient expression analyses revealed that TaNAC69-1 bound to the promoters of TaSHY2 and TaIAA7, acted as a transcriptional repressor and repressed the expression of reporter genes driven by the TaSHY2 or TaIAA7 promoter. These data suggest that TaNAC69-1 is a transcriptional repressor of TaSHY2 and TaIAA7 homologous to Arabidopsis negative root growth regulators and is likely to be involved in promoting root elongation in drying soil. © 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.

Transcriptional profiling of the pea shoot apical meristem reveals processes underlying its function and maintenance

PubMed Central

Wong, Chui E; Bhalla, Prem L; Ottenhof, Harald; Singh, Mohan B

2008-01-01

Background Despite the importance of the shoot apical meristem (SAM) in plant development and organ formation, our understanding of the molecular mechanisms controlling its function is limited. Genomic tools have the potential to unravel the molecular mysteries of the SAM, and legume systems are increasingly being used in plant-development studies owing to their unique characteristics such as nitrogen fixation, secondary metabolism, and pod development. Garden pea (Pisum sativum) is a well-established classic model species for genetics studies that has been used since the Mendel era. In addition, the availability of a plethora of developmental mutants makes pea an ideal crop legume for genomics studies. This study aims to utilise genomics tools in isolating genes that play potential roles in the regulation of SAM activity. Results In order to identify genes that are differentially expressed in the SAM, we generated 2735 ESTs from three cDNA libraries derived from freshly micro-dissected SAMs from 10-day-old garden peas (Pisum sativum cv Torsdag). Custom-designed oligonucleotide arrays were used to compare the transcriptional profiles of pea SAMs and non-meristematic tissues. A total of 184 and 175 transcripts were significantly up- or down-regulated in the pea SAM, respectively. As expected, close to 61% of the transcripts down-regulated in the SAM were found in the public database, whereas sequences from the same source only comprised 12% of the genes that were expressed at higher levels in the SAM. This highlights the under-representation of transcripts from the meristematic tissues in the current public pea protein database, and demonstrates the utility of our SAM EST collection as an essential genetic resource for revealing further information on the regulation of this developmental process. In addition to unknowns, many of the up-regulated transcripts are known to encode products associated with cell division and proliferation, epigenetic regulation, auxin-mediated responses and microRNA regulation. Conclusion The presented data provide a picture of the transcriptional profile of the pea SAM, and reveal possible roles of differentially expressed transcripts in meristem function and maintenance. PMID:18590528

Protein arginine methyltransferase 5 is an essential component of the hypoxia-inducible factor 1 signaling pathway

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

Lim, Ji-Hong; Choi, Yong-Joon; Cho, Chung-Hyun

2012-02-10

Highlights: Black-Right-Pointing-Pointer HIF-1{alpha} is expressed PRMT5-dependently in hypoxic cancer cells. Black-Right-Pointing-Pointer The HIF-1 regulation of hypoxia-induced genes is attenuated in PRMT5-knocked-down cells. Black-Right-Pointing-Pointer The de novo synthesis of HIF-1{alpha} depends on PRMT5. Black-Right-Pointing-Pointer PRMT5 is involved in the HIF-1{alpha} translation initiated by 5 Prime UTR of HIF-1{alpha} mRNA. -- Abstract: Protein arginine methyltransferase 5 (PRMT5) is an enzyme that transfers one or two methyl groups to the arginine residues of histones or non-histone proteins, and that plays critical roles in cellular processes as diverse as receptor signaling and gene expression. Furthermore, PRMT5 is highly expressed in tumors, where it maymore » be associated with tumor growth. Although much research has been conducted on PRMT5, little is known regarding its role in adaption to hypoxia. As hypoxia-inducible factor 1 (HIF-1) is a key player in hypoxic response, we examined the possible involvement of PRMT5 in the HIF-1 signaling pathway. Of the siRNAs targeting PRMT1-8, only PRMT5 siRNA attenuated the hypoxic induction of HIF-1{alpha} in A549 cells, and this result was reproducible in all three cancer cell lines examined. PRMT5 knock-down also repressed the promoter activities and the transcript levels of HIF-1-governed genes. Mechanistically, de novo synthesis of HIF-1{alpha} protein was reduced in PRMT5-knocked-down A549 cells, and this was rescued by PRMT5 restoration. In contrast, HIF-1{alpha} transcription, RNA processing, and protein stability were unaffected by PRMT5 knock-down. Furthermore, PRMT5 was found to be essential for the HIF-1{alpha} translation initiated by the 5 Prime UTR of HIF-1{alpha} mRNA. Given our results and previous reports, we believe that PRMT5 probably promotes tumor growth by stimulating cell proliferation and by participating in the construction of a tumor-favorable microenvironment via HIF-1 activation.« less

Down-regulation of Cyclooxygenase-2 by the Carboxyl Tail of the Angiotensin II Type 1 Receptor*

PubMed Central

Sood, Rapita; Minzel, Waleed; Rimon, Gilad; Tal, Sharon; Barki-Harrington, Liza

2014-01-01

The enzyme cyclooxygenase-2 (COX-2) plays an important role in the kidney by up-regulating the production of the vasoconstrictor hormone angiotensin II (AngII), which in turn down-regulates COX-2 expression via activation of the angiotensin II type 1 receptor (AT1) receptor. Chemical inhibition of the catalytic activity of COX-2 is a well-established strategy for treating inflammation but little is known of cellular mechanisms that dispose of the protein itself. Here we show that in addition to its indirect negative feedback on COX-2, AT1 also down-regulates the expression of the COX-2 protein via a pathway that does not involve G-protein or β-arrestin-dependent signaling. Instead, AT1 enhances the ubiquitination and subsequent degradation of the enzyme in the proteasome through elements in its cytosolic carboxyl tail (CT). We find that a mutant receptor that lacks the last 35 amino acids of its CT (Δ324) is devoid of its ability to reduce COX-2, and that expression of the CT sequence alone is sufficient to down-regulate COX-2. Collectively these results propose a new role for AT1 in regulating COX-2 expression in a mechanism that deviates from its canonical signaling pathways. Down-regulation of COX-2 by a short peptide that originates from AT1 may present as a basis for novel therapeutic means of eliminating excess COX-2 protein. PMID:25231994

MiR-217 is down-regulated in psoriasis and promotes keratinocyte differentiation via targeting GRHL2

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

Zhu, Haigang; Hou, Liyue; Liu, Jingjing

MiR-217 is a well-known tumor suppressor, and its down-regulation has been shown in a wide range of solid and leukaemic cancers. However, the biological role of miR-217 in psoriasis pathogenesis, especially in keratinocyte hyperproliferation and differentiation, is not clearly understood. In this study, we found the expression of miR-217 was markedly down-regulated in psoriasis keratinocytes of psoriatic patients. In addition, overexpression of miR-217 inhibited the proliferation and promoted the differentiation of primary human keratinocytes. On the contrary, inhibition of endogenous miR-217 increased cell proliferation and delayed differentiation. Furthermore, Grainyhead-like 2 (GRHL2) was identified as a direct target of miR-217 bymore » luciferase reporter assay. The expression of miR-217 and GRHL2 was inversely correlated in both transfected keratinocytes and in psoriasis lesional skin. Moreover, knocking down GRHL2 expression by siRNA enhanced keratinocyte differentiation. Taken together, our results demonstrate a role for miR-217 in the regulation of keratinocyte differentiation, partially through the regulation of GRHL2. - Highlights: • miR-217 is down-regulated in psoriasis skin lesions. • miR-217 inhibits the proliferation and promotes differentiation of keratinocytes. • GRHL2 is a novel target of miR-217 in keratinocytes. • GRHL2 is up-regulated and inversely correlated with miR-217 in psoriasis skin lesions.« less

Cool-associated Tyrosine-phosphorylated Protein 1 Is Required for the Anchorage-independent Growth of Cervical Carcinoma Cells by Binding Paxillin and Promoting AKT Activation*

PubMed Central

Yoo, Sungsoo M.; Latifkar, Arash; Cerione, Richard A.; Antonyak, Marc A.

2017-01-01

Cool-associated tyrosine-phosphorylated protein 1 (Cat-1) is a signaling scaffold as well as an ADP-ribosylation factor-GTPase-activating protein. Although best known for its role in cell migration, we recently showed that the ability of Cat-1 to bind paxillin, a major constituent of focal complexes, is also essential for the anchorage-independent growth of HeLa cervical carcinoma cells. Here we set out to learn more about the underlying mechanism by which Cat-paxillin interactions mediate this effect. We show that knocking down paxillin expression in HeLa cells promotes their ability to form colonies in soft agar, whereas ectopically expressing paxillin in these cells inhibits this transformed growth phenotype. Although knocking down Cat-1 prevents HeLa cells from forming colonies in soft agar, when paxillin is knocked down together with Cat-1, the cells are again able to undergo anchorage-independent growth. These results suggest that the requirement of Cat-1 for this hallmark of cellular transformation is coupled to its ability to bind paxillin and abrogate its actions as a negative regulator of anchorage-independent growth. We further show that knocking down Cat-1 expression in HeLa cells leads to a reduction in Akt activation, which can be reversed by knocking down paxillin. Moreover, expression of constitutively active forms of Akt1 and Akt2 restores the anchorage-independent growth capability of HeLa cells depleted of Cat-1 expression. Together, these findings highlight a novel mechanism whereby interactions between Cat-1 and its binding partner paxillin are necessary to ensure sufficient Akt activation so that cancer cells are able to grow under anchorage-independent conditions. PMID:28100775

Cool-associated Tyrosine-phosphorylated Protein 1 Is Required for the Anchorage-independent Growth of Cervical Carcinoma Cells by Binding Paxillin and Promoting AKT Activation.

PubMed

Yoo, Sungsoo M; Latifkar, Arash; Cerione, Richard A; Antonyak, Marc A

2017-03-03

Cool-associated tyrosine-phosphorylated protein 1 (Cat-1) is a signaling scaffold as well as an ADP-ribosylation factor-GTPase-activating protein. Although best known for its role in cell migration, we recently showed that the ability of Cat-1 to bind paxillin, a major constituent of focal complexes, is also essential for the anchorage-independent growth of HeLa cervical carcinoma cells. Here we set out to learn more about the underlying mechanism by which Cat-paxillin interactions mediate this effect. We show that knocking down paxillin expression in HeLa cells promotes their ability to form colonies in soft agar, whereas ectopically expressing paxillin in these cells inhibits this transformed growth phenotype. Although knocking down Cat-1 prevents HeLa cells from forming colonies in soft agar, when paxillin is knocked down together with Cat-1, the cells are again able to undergo anchorage-independent growth. These results suggest that the requirement of Cat-1 for this hallmark of cellular transformation is coupled to its ability to bind paxillin and abrogate its actions as a negative regulator of anchorage-independent growth. We further show that knocking down Cat-1 expression in HeLa cells leads to a reduction in Akt activation, which can be reversed by knocking down paxillin. Moreover, expression of constitutively active forms of Akt1 and Akt2 restores the anchorage-independent growth capability of HeLa cells depleted of Cat-1 expression. Together, these findings highlight a novel mechanism whereby interactions between Cat-1 and its binding partner paxillin are necessary to ensure sufficient Akt activation so that cancer cells are able to grow under anchorage-independent conditions. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Knock down of the myostatin gene by RNA interference increased body weight in chicken.

PubMed

Bhattacharya, T K; Shukla, R; Chatterjee, R N; Dushyanth, K

2017-01-10

Myostatin is a negative regulator of muscular growth in poultry and other animals. Of several approaches, knocking down the negative regulator is an important aspect to augment muscular growth in chicken. Knock down of myostatin gene has been performed by shRNA acting against the expression of gene in animals. Two methods of knock down of gene in chicken such as embryo manipulation and sperm mediated method have been performed. The hatching percentage in embryo manipulation and sperm mediated method of knock down was 58.0 and 41.5%, respectively. The shRNA in knock down chicken enhanced body weight at 6 weeks by 26.9%. The dressing percentage and serum biochemical parameters such as SGPT and alkaline phosphatase differed significantly (P<0.05) between knock down and control birds. It is concluded that knocking down the myostatin gene successfully augmented growth in chicken. Copyright © 2016 Elsevier B.V. All rights reserved.

The up and down of sleep: From molecules to electrophysiology.

PubMed

Navarro-Lobato, Irene; Genzel, Lisa

2018-03-12

Alternations of up and down can be seen across many different levels during sleep. Neural firing-rates, synaptic markers, molecular pathways, and gene expression all show differential up and down regulation across brain areas and sleep stages. And also the hallmarks of sleep - sleep stage specific oscillations - are characterized themselves by up and down as seen within the slow oscillation or theta cycles. In this review, we summarize the up and down of sleep covering molecules to electrophysiology and present different theories how this up and down could be regulated by the up and down of sleep oscillations. Further, we propose a tentative theory how this differential up and down could contribute to various outcomes of sleep related memory consolidation: enhancement of hippocampal representations of very novel memories and cortical consolidation of memories congruent with previous knowledge-networks. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Photosynthesis down-regulation precedes carbohydrate accumulation under sink limitation in Citrus.

PubMed

Nebauer, Sergio G; Renau-Morata, Begoña; Guardiola, José Luis; Molina, Rosa-Victoria

2011-02-01

Photosynthesis down-regulation due to an imbalance between sources and sinks in Citrus leaves could be mediated by excessive accumulation of carbohydrates. However, there is limited understanding of the physiological role of soluble and insoluble carbohydrates in photosynthesis regulation and the elements triggering the down-regulation process. In this work, the role of non-structural carbohydrates in the regulation of photosynthesis under a broad spectrum of source-sink relationships has been investigated in the Salustiana sweet orange. Soluble sugar and starch accumulation in leaves, induced by girdling experiments, did not induce down-regulation of the photosynthetic rate in the presence of sinks (fruits). The leaf-to-fruit ratio did not modulate photosynthesis but allocation of photoassimilates to the fruits. The lack of strong sink activity led to a decrease in the photosynthetic rate and starch accumulation in leaves. However, photosynthesis down-regulation due to an excess of total soluble sugars or starch was discarded because photosynthesis and stomatal conductance reduction occurred prior to any significant accumulation of these carbohydrates. Gas exchange and fluorescence parameters suggested biochemical limitations to photosynthesis. In addition, the expression of carbon metabolism-related genes was altered within 24 h when strong sinks were removed. Sucrose synthesis and export genes were inhibited, whereas the expression of ADP-glucose pyrophosphorylase was increased to cope with the excess of assimilates. In conclusion, changes in starch and soluble sugar turnover, but not sugar content per se, could provide the signal for photosynthesis regulation. In these conditions, non-stomatal limitations strongly inhibited the photosynthetic rate prior to any significant increase in carbohydrate levels.

Anti-biofilm, anti-hemolysis, and anti-virulence activities of black pepper, cananga, myrrh oils, and nerolidol against Staphylococcus aureus.

PubMed

Lee, Kayeon; Lee, Jin-Hyung; Kim, Soon-Il; Cho, Moo Hwan; Lee, Jintae

2014-11-01

The long-term usage of antibiotics has resulted in the evolution of multidrug-resistant bacteria. Unlike antibiotics, anti-virulence approaches target bacterial virulence without affecting cell viability, which may be less prone to develop drug resistance. Staphylococcus aureus is a major human pathogen that produces diverse virulence factors, such as α-toxin, which is hemolytic. Also, biofilm formation of S. aureus is one of the mechanisms of its drug resistance. In this study, anti-biofilm screening of 83 essential oils showed that black pepper, cananga, and myrrh oils and their common constituent cis-nerolidol at 0.01 % markedly inhibited S. aureus biofilm formation. Furthermore, the three essential oils and cis-nerolidol at below 0.005 % almost abolished the hemolytic activity of S. aureus. Transcriptional analyses showed that black pepper oil down-regulated the expressions of the α-toxin gene (hla), the nuclease genes, and the regulatory genes. In addition, black pepper, cananga, and myrrh oils and cis-nerolidol attenuated S. aureus virulence in the nematode Caenorhabditis elegans. This study is one of the most extensive on anti-virulence screening using diverse essential oils and provides comprehensive data on the subject. This finding implies other beneficial effects of essential oils and suggests that black pepper, cananga, and myrrh oils have potential use as anti-virulence strategies against persistent S. aureus infections.

Estimates of downed woody debris decay class transitions for forests across the eastern United States

Treesearch

Matthew B. Russell; Christopher W. Woodall; Shawn Fraver; Anthony W. D' Amato

2013-01-01

Large-scale inventories of downed woody debris (DWD; downed dead wood of a minimum size) often record decay status by assigning pieces to classes of decay according to their visual/structural attributes (e.g., presence of branches, log shape, and texture and color of wood). DWD decay classes are not only essential for estimating current DWD biomass and carbon stocks,...

PPARγ regulates exocrine pancreas lipase.

PubMed

Danino, Hila; Naor, Ronny Peri-; Fogel, Chen; Ben-Harosh, Yael; Kadir, Rotem; Salem, Hagit; Birk, Ruth

2016-12-01

Pancreatic lipase (triacylglycerol lipase EC 3.1.1.3) is an essential enzyme in hydrolysis of dietary fat. Dietary fat, especially polyunsaturated fatty acids (PUFA), regulate pancreatic lipase (PNLIP); however, the molecular mechanism underlying this regulation is mostly unknown. As PUFA are known to regulate expression of proliferator-activated receptor gamma (PPARγ), and as we identified in-silico putative PPARγ binding sites within the putative PNLIP promoter sequence, we hypothesized that PUFA regulation of PNLIP might be mediated by PPARγ. We used in silico bioinformatics tools, reporter luciferase assay, PPARγ agonists and antagonists, PPARγ overexpression in exocrine pancreas AR42J and primary cells to study PPARγ regulation of PNLIP. Using in silico bioinformatics tools we mapped PPARγ binding sites (PPRE) to the putative promoter region of PNLIP. Reporter luciferase assay in AR42J rat exocrine pancreas acinar cells transfected with various constructs of the putative PNLIP promoter showed that PNLIP transcription is significantly enhanced by PPARγ dose-dependently, reaching maximal levels with multi PPRE sites. This effect was significantly augmented in the presence of PPARγ agonists and reduced by PPARγ antagonists or mutagenesis abrogating PPRE sites. Over-expression of PPARγ significantly elevated PNLIP transcript and protein levels in AR42J cells and in primary pancreas cells. Moreover, PNLIP expression was up-regulated by PPARγ agonists (pioglitazone and 15dPGJ2) and significantly down-regulated by PPARγ antagonists in non-transfected rat exocrine pancreas AR42J cell line cells. PPARγ transcriptionally regulates PNLIP gene expression. This transcript regulation resolves part of the missing link between dietary PUFA direct regulation of PNLIP. Copyright © 2016 Elsevier B.V. All rights reserved.

Up-regulation of heat shock proteins is essential for cold survival during insect diapause

PubMed Central

Rinehart, Joseph P.; Li, Aiqing; Yocum, George D.; Robich, Rebecca M.; Hayward, Scott A. L.; Denlinger, David L.

2007-01-01

Diapause, the dormancy common to overwintering insects, evokes a unique pattern of gene expression. In the flesh fly, most, but not all, of the fly's heat shock proteins (Hsps) are up-regulated. The diapause up-regulated Hsps include two members of the Hsp70 family, one member of the Hsp60 family (TCP-1), at least four members of the small Hsp family, and a small Hsp pseudogene. Expression of an Hsp70 cognate, Hsc70, is uninfluenced by diapause, and Hsp90 is actually down-regulated during diapause, thus diapause differs from common stress responses that elicit synchronous up-regulation of all Hsps. Up-regulation of the Hsps begins at the onset of diapause, persists throughout the overwintering period, and ceases within hours after the fly receives the signal to reinitiate development. The up-regulation of Hsps appears to be common to diapause in species representing diverse insect orders including Diptera, Lepidoptera, Coleoptera, and Hymenoptera as well as in diapauses that occur in different developmental stages (embryo, larva, pupa, adult). Suppressing expression of Hsp23 and Hsp70 in flies by using RNAi did not alter the decision to enter diapause or the duration of diapause, but it had a profound effect on the pupa's ability to survive low temperatures. We thus propose that up-regulation of Hsps during diapause is a major factor contributing to cold-hardiness of overwintering insects. PMID:17522254

Epithelial-stromal interaction via Notch signaling is essential for the full maturation of gut-associated lymphoid tissues.

PubMed

Obata, Yuuki; Kimura, Shunsuke; Nakato, Gaku; Iizuka, Keito; Miyagawa, Yurika; Nakamura, Yutaka; Furusawa, Yukihiro; Sugiyama, Machiko; Suzuki, Keiichiro; Ebisawa, Masashi; Fujimura, Yumiko; Yoshida, Hisahiro; Iwanaga, Toshihiko; Hase, Koji; Ohno, Hiroshi

2014-12-01

Intrinsic Notch signaling in intestinal epithelial cells restricts secretory cell differentiation. In gut-associated lymphoid tissue (GALT), stromal cells located beneath the follicle-associated epithelium (FAE) abundantly express the Notch ligand delta-like 1 (Dll1). Here, we show that mice lacking Rbpj-a gene encoding a transcription factor implicated in Notch signaling-in intestinal epithelial cells have defective GALT maturation. This defect can be attributed to the expansion of goblet cells, which leads to the down-regulation of CCL20 in FAE. These data demonstrate that epithelial Notch signaling maintained by stromal cells contributes to the full maturation of GALT by restricting secretory cell differentiation in FAE. © 2014 The Authors.

Transcriptional responses of Arabidopsis thaliana to chewing and sucking insect herbivores

DOE PAGES

Appel, Heidi M.; Fescemyer, Howard; Ehlting, Juergen; ...

2014-11-14

We tested the hypothesis that Arabidopsis can recognize and respond differentially to insect species at the transcriptional level using a genome wide microarray. Transcriptional reprogramming was characterized using co-expression analysis in damaged and undamaged leaves at two times in response to mechanical wounding and four insect species. In all, 2778 (10.6%) of annotated genes on the array were differentially expressed in at least one treatment. Responses differed mainly between aphid and caterpillar and sampling times. Responses to aphids and caterpillars shared only 10% of up-regulated and 8% of down-regulated genes. Responses to two caterpillars shared 21 and 12% of up-more » and down-regulated genes, whereas responses to the two aphids shared only 7 and 4% of up-regulated and down-regulated genes. Overlap in genes expressed between 6 and 24 h was 3–15%, and depended on the insect species. Responses in attacked and unattacked leaves differed at 6 h but converged by 24 h. Genes responding to the insects are also responsive to many stressors and included primary metabolism. Aphids down-regulated amino acid catabolism; caterpillars stimulated production of amino acids involved in glucosinolate synthesis. Co-expression analysis revealed 17 response networks. Transcription factors were a major portion of differentially expressed genes throughout and responsive genes shared most of the known or postulated binding sites. However, cis-element composition of genes down regulated by the aphid M. persicae was unique, as were those of genes down-regulated by caterpillars. As many as 20 cis-elements were over-represented in one or more treatments, including some from well-characterized classes and others as yet uncharacterized. We suggest that transcriptional changes elicited by wounding and insects are heavily influenced by transcription factors and involve both enrichment of a common set of cis-elements and a unique enrichment of a few cis-elements in responding genes.« less

Transcriptional responses of Arabidopsis thaliana to chewing and sucking insect herbivores

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

Appel, Heidi M.; Fescemyer, Howard; Ehlting, Juergen

We tested the hypothesis that Arabidopsis can recognize and respond differentially to insect species at the transcriptional level using a genome wide microarray. Transcriptional reprogramming was characterized using co-expression analysis in damaged and undamaged leaves at two times in response to mechanical wounding and four insect species. In all, 2778 (10.6%) of annotated genes on the array were differentially expressed in at least one treatment. Responses differed mainly between aphid and caterpillar and sampling times. Responses to aphids and caterpillars shared only 10% of up-regulated and 8% of down-regulated genes. Responses to two caterpillars shared 21 and 12% of up-more » and down-regulated genes, whereas responses to the two aphids shared only 7 and 4% of up-regulated and down-regulated genes. Overlap in genes expressed between 6 and 24 h was 3–15%, and depended on the insect species. Responses in attacked and unattacked leaves differed at 6 h but converged by 24 h. Genes responding to the insects are also responsive to many stressors and included primary metabolism. Aphids down-regulated amino acid catabolism; caterpillars stimulated production of amino acids involved in glucosinolate synthesis. Co-expression analysis revealed 17 response networks. Transcription factors were a major portion of differentially expressed genes throughout and responsive genes shared most of the known or postulated binding sites. However, cis-element composition of genes down regulated by the aphid M. persicae was unique, as were those of genes down-regulated by caterpillars. As many as 20 cis-elements were over-represented in one or more treatments, including some from well-characterized classes and others as yet uncharacterized. We suggest that transcriptional changes elicited by wounding and insects are heavily influenced by transcription factors and involve both enrichment of a common set of cis-elements and a unique enrichment of a few cis-elements in responding genes.« less

Climate-mediated changes in marine ecosystem regulation during El Niño.

PubMed

Lindegren, Martin; Checkley, David M; Koslow, Julian A; Goericke, Ralf; Ohman, Mark D

2018-02-01

The degree to which ecosystems are regulated through bottom-up, top-down, or direct physical processes represents a long-standing issue in ecology, with important consequences for resource management and conservation. In marine ecosystems, the role of bottom-up and top-down forcing has been shown to vary over spatio-temporal scales, often linked to highly variable and heterogeneously distributed environmental conditions. Ecosystem dynamics in the Northeast Pacific have been suggested to be predominately bottom-up regulated. However, it remains unknown to what extent top-down regulation occurs, or whether the relative importance of bottom-up and top-down forcing may shift in response to climate change. In this study, we investigate the effects and relative importance of bottom-up, top-down, and physical forcing during changing climate conditions on ecosystem regulation in the Southern California Current System (SCCS) using a generalized food web model. This statistical approach is based on nonlinear threshold models and a long-term data set (~60 years) covering multiple trophic levels from phytoplankton to predatory fish. We found bottom-up control to be the primary mode of ecosystem regulation. However, our results also demonstrate an alternative mode of regulation represented by interacting bottom-up and top-down forcing, analogous to wasp-waist dynamics, but occurring across multiple trophic levels and only during periods of reduced bottom-up forcing (i.e., weak upwelling, low nutrient concentrations, and primary production). The shifts in ecosystem regulation are caused by changes in ocean-atmosphere forcing and triggered by highly variable climate conditions associated with El Niño. Furthermore, we show that biota respond differently to major El Niño events during positive or negative phases of the Pacific Decadal Oscillation (PDO), as well as highlight potential concerns for marine and fisheries management by demonstrating increased sensitivity of pelagic fish to exploitation during El Niño. © 2017 John Wiley & Sons Ltd.

ROS Production Is Essential for the Apoptotic Function of E2F1 in Pheochromocytoma and Neuroblastoma Cell Lines

PubMed Central

Espada, Lilia; Meo-Evoli, Nathalie; Sancho, Patricia; Real, Sebastian; Fabregat, Isabel; Ambrosio, Santiago; Tauler, Albert

2012-01-01

In this study we demonstrate that accumulation of reactive oxygen species (ROS) is essential for E2F1 mediated apoptosis in ER-E2F1 PC12 pheochromocytoma, and SH-SY5Y and SK-N-JD neuroblastoma stable cell lines. In these cells, the ER-E2F1 fusion protein is expressed in the cytosol; the addition of 4-hydroxytamoxifen (OHT) induces its translocation to the nucleus and activation of E2F1target genes. Previously we demonstrated that, in ER-E2F1 PC12 cells, OHT treatment induced apoptosis through activation of caspase-3. Here we show that caspase-8 activity did not change upon treatment with OHT. Moreover, over-expression of Bcl-xL arrested OHT-induced apoptosis; by contrast, over-expression of c-FLIP, did not have any effect on OHT-induced apoptosis. OHT addition induces BimL expression, its translocation to mitochondria and activation of Bax, which is paralleled by diminished mitochondrial enrichment of Bcl-xL. Treatment with a Bax-inhibitory peptide reduced OHT-induced apoptosis. These results point out the essential role of mitochondria on the apoptotic process driven by E2F1. ROS accumulation followed E2F1 induction and treatment with the antioxidant N-acetylcysteine, inhibited E2F1-induced Bax translocation to mitochondria and subsequent apoptosis. The role of ROS in mediating OHT-induced apoptosis was also studied in two neuroblastoma cell lines, SH-SY5Y and SK-N-JD. In SH-SY5Y cells, activation of E2F1 by the addition of OHT induced ROS production and apoptosis, whereas over-expression of E2F1 in SK-N-JD cells failed to induce either response. Transcriptional profiling revealed that many of the genes responsible for scavenging ROS were down-regulated following E2F1-induction in SH-SY5Y, but not in SK-N-JD cells. Finally, inhibition of GSK3β blocked ROS production, Bax activation and the down regulation of ROS scavenging genes. These findings provide an explanation for the apparent contradictory role of E2F1 as an apoptotic agent versus a cell cycle activator. PMID:23251571

Gravin regulates mesodermal cell behavior changes required for axis elongation during zebrafish gastrulation.

PubMed

Weiser, Douglas C; Pyati, Ujwal J; Kimelman, David

2007-06-15

Convergent extension of the mesoderm is the major driving force of vertebrate gastrulation. During this process, mesodermal cells move toward the future dorsal side of the embryo, then radically change behavior as they initiate extension of the body axis. How cells make this transition in behavior is unknown. We have identified the scaffolding protein and tumor suppressor Gravin as a key regulator of this process in zebrafish embryos. We show that Gravin is required for the conversion of mesodermal cells from a highly migratory behavior to the medio-laterally intercalative behavior required for body axis extension. In the absence of Gravin, paraxial mesodermal cells fail to shut down the protrusive activity mediated by the Rho/ROCK/Myosin II pathway, resulting in embryos with severe extension defects. We propose that Gravin functions as an essential scaffold for regulatory proteins that suppress the migratory behavior of the mesoderm during gastrulation, and suggest that this function also explains how Gravin inhibits invasive behaviors in metastatic cells.

A Miniaturized 0.78-mW/cm2 Autonomous Thermoelectric Energy-Harvesting Platform for Biomedical Sensors.

PubMed

Rozgic, Dejan; Markovic, Dejan

2017-08-01

In order to use thermoelectric energy harvesters (TEHs) as a truly autonomous energy source for size-limited sensing applications, it is essential to improve the power conversion efficiency and energy density. This study presents a thin-film, array-based TEH with a surface area of 0.83 cm 2 . The TEH autonomously supplies a power management IC fabricated in a 65-nm CMOS technology. The IC utilizes a single-inductor topology with integrated analog maximum power point tracking (MPPT), resulting in a 68% peak end-to-end efficiency (92% converter efficiency) and less than 20-ms MPPT. In an in-vivo test, a 645-μW regulated output power (effective 3.5 K of temperature gradient) was harvested from a rat implanted with our TEH, demonstrating true energy independence in a real environment while showing a 7.9 × improvement in regulated power density compared to the state-of-the-art. The system showed autonomous operation down to 65-mV TEH input.

Analysis of the crystal structure of an active MCM hexamer.

PubMed

Miller, Justin M; Arachea, Buenafe T; Epling, Leslie B; Enemark, Eric J

2014-09-29

In a previous Research article (Froelich et al., 2014), we suggested an MCM helicase activation mechanism, but were limited in discussing the ATPase domain because it was absent from the crystal structure. Here we present the crystal structure of a nearly full-length MCM hexamer that is helicase-active and thus has all features essential for unwinding DNA. The structure is a chimera of Sulfolobus solfataricus N-terminal domain and Pyrococcus furiosus ATPase domain. We discuss three major findings: 1) a novel conformation for the A-subdomain that could play a role in MCM regulation; 2) interaction of a universally conserved glutamine in the N-terminal Allosteric Communication Loop with the AAA+ domain helix-2-insert (h2i); and 3) a recessed binding pocket for the MCM ssDNA-binding motif influenced by the h2i. We suggest that during helicase activation, the h2i clamps down on the leading strand to facilitate strand retention and regulate ATP hydrolysis.

Perturbation in protein expression of the sterile salmonid hybrids between female brook trout Salvelinus fontinalis and male masu salmon Oncorhynchus masou during early spermatogenesis.

PubMed

Zheng, Liang; Senda, Yoshie; Abe, Syuiti

2013-05-01

Most males and females of intergeneric hybrid (BM) between female brook trout (Bt) Salvelinus fontinalis and male masu salmon (Ms) Oncorhynchus masou had undeveloped gonads, with abnormal germ cell development shown by histological examination. To understand the cause of this hybrid sterility, expression profiles of testicular proteins in the BM and parental species were examined with 2-DE coupled with MALDI-TOF/TOF MS. Compared with the parental species, more than 60% of differentially expressed protein spots were down-regulated in BM. A total of 16 up-regulated and 48 down-regulated proteins were identified in BM. Up-regulated were transferrin and other somatic cell-predominant proteins, whereas down-regulated were some germ cell-specific proteins such as DEAD box RNA helicase Vasa. Other pronouncedly down-regulated proteins included tubulins and heat shock proteins that are supposed to have roles in spermatogenesis. The present findings suggest direct association of the observed perturbation in protein expression with the failure of spermatogenesis and the sterility in the examined salmonid hybrids. Copyright © 2013 Elsevier B.V. All rights reserved.

The effects of spaceflight on adrenergic receptors and agonists and cell adhesion molecule expression

NASA Technical Reports Server (NTRS)

Mills, Paul J.; Perez, Christy J.; Adler, Karen A.; Ziegler, Michael G.; Meck, J. V. (Principal Investigator)

2002-01-01

Twenty-two astronauts who flew aboard 10 different US Space Shuttle flights were studied 10 days before launch, on landing day, and 2-4 days post-landing. After landing, plasma levels of norepinephrine (p<0.01) were elevated. Lymphocyte beta(2)-adrenergic receptors were desensitized 2-4 days post-landing (p<0.02). The density of CD62L on lymphocytes was unchanged but the densities of CD11a (p<0.01) and CD54 (p<0.001) were down-regulated. CD11a density was also down-regulated on monocytes (p<0.01). Neutrophils showed an up-regulation of CD11a (p<0.01) and a down-regulation of CD54 (p<0.01). CD11a density on neutrophils remained up-regulated (p<0.01) and CD54 density remained down-regulated (p<0.01) at 2-4 days post-landing. Circulating levels of soluble ICAM-1 (CD54) and soluble E-selectin (CD62E) were decreased after landing (p's<0.05). The data suggest that spaceflight leads to an environment that would support reduced leukocyte-endothelial adhesion. Sympathetic activation may contribute to this phenomenon.

Efficacy of Histone Deacetylase and Estrogen Receptor Inhibition in Breast Cancer Cells Due to Concerted down Regulation of Akt

PubMed Central

Thomas, Scott; Thurn, K. Ted; Raha, Paromita; Chen, Stephanie; Munster, Pamela N.

2013-01-01

Hormonal therapy resistance remains a considerable barrier in the treatment of breast cancer. Activation of the Akt-PI3K-mTOR pathway plays an important role in hormonal therapy resistance. Our recent preclinical and clinical studies showed that the addition of a histone deacetylase inhibitor re-sensitized hormonal therapy resistant breast cancer to tamoxifen. As histone deacetylases are key regulators of Akt, we evaluated the effect of combined treatment with the histone deacetylase inhibitor PCI-24781 and tamoxifen on Akt in breast cancer cells. We demonstrate that while both histone deacetylase and estrogen receptor inhibition down regulate AKT mRNA and protein, their concerted effort results in down regulation of AKT activity with induction of cell death. Histone deacetylase inhibition exerts its effect on AKT mRNA through an estrogen receptor-dependent mechanism, primarily down regulating the most abundant isoform AKT1. Although siRNA depletion of AKT modestly induces cell death, when combined with an anti-estrogen, cytotoxicity is significantly enhanced. Thus, histone deacetylase regulation of AKT mRNA is a key mediator of this therapeutic combination and may represent a novel biomarker for predicting response to this regimen. PMID:23874830

Epidemiology, clinical characteristics, laboratory findings and severity of respiratory syncytial virus acute lower respiratory infection in Malaysian children, 2008-2013.

PubMed

Ng, Khuen F; Tan, Kah K; Sam, Zhi H; Ting, Grace Ss; Gan, Wan Y

2017-04-01

The aim of this study is to describe epidemiology, clinical features, laboratory data and severity of respiratory syncytial virus (RSV) acute lower respiratory infection (ALRI) in Malaysian children and to determine risk factors associated with prolonged hospital stay, paediatric intensive care unit (PICU) admission and mortality. Retrospective data on demographics, clinical presentation, outcomes and laboratory findings of 450 children admitted into Tuanku Jaafar Hospital in Seremban, Malaysia from 2008 to 2013 with documented diagnosis of RSV ALRI were collected and analysed. Most admissions were children below 2 years old (85.8%; 386/450). Commonest symptoms were fever (84.2%; 379/450), cough (97.8%; 440/450) and rhinorrhea (83.6%; 376/450). The median age among febrile patients (n = 379) was 9.0 months with interquartile range (IQR) of 4.0-19.0 months whereas the median age among those who were apyrexial (n = 71) was 2 months with IQR of 1-6 months (P-value <0.001). 15.3% (69/450) needed intensive care and 1.6% (7/450) died. Young age, history of prematurity, chronic comorbidity and thrombocytosis were significantly associated with prolonged hospital stay, PICU admission and mortality. Infants less than 6 months old with RSV ALRI tend to be afebrile at presentation. Younger age, history of prematurity, chronic comorbidity and thrombocytosis are predictors of severe RSV ALRI among Malaysian children. Case fatality rate for Malaysian children below 5 years of age with RSV ALRI in our centre is higher than what is seen in developed countries, suggesting that there is room for improvement. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

Anastomotic leak after colorectal resection: A population-based study of risk factors and hospital variation.

PubMed

Nikolian, Vahagn C; Kamdar, Neil S; Regenbogen, Scott E; Morris, Arden M; Byrn, John C; Suwanabol, Pasithorn A; Campbell, Darrell A; Hendren, Samantha

2017-06-01

Anastomotic leak is a major source of morbidity in colorectal operations and has become an area of interest in performance metrics. It is unclear whether anastomotic leak is associated primarily with surgeons' technical performance or explained better by patient characteristics and institutional factors. We sought to establish if anastomotic leak could serve as a valid quality metric in colorectal operations by evaluating provider variation after adjusting for patient factors. We performed a retrospective cohort study of colorectal resection patients in the Michigan Surgical Quality Collaborative. Clinically relevant patient and operative factors were tested for association with anastomotic leak. Hierarchical logistic regression was used to derive risk-adjusted rates of anastomotic leak. Of 9,192 colorectal resections, 244 (2.7%) had a documented anastomotic leak. The incidence of anastomotic leak was 3.0% for patients with pelvic anastomoses and 2.5% for those with intra-abdominal anastomoses. Multivariable analysis showed that a greater operative duration, male sex, body mass index >30 kg/m 2 , tobacco use, chronic immunosuppressive medications, thrombocytosis (platelet count >400 × 10 9 /L), and urgent/emergency operations were independently associated with anastomotic leak (C-statistic = 0.75). After accounting for patient and procedural risk factors, 5 hospitals had a significantly greater incidence of postoperative anastomotic leak. This population-based study shows that risk factors for anastomotic leak include male sex, obesity, tobacco use, immunosuppression, thrombocytosis, greater operative duration, and urgent/emergency operation; models including these factors predict most of the variation in anastomotic leak rates. This study suggests that anastomotic leak can serve as a valid metric that can identify opportunities for quality improvement. Copyright © 2017 Elsevier Inc. All rights reserved.

SEPALLATA3: the 'glue' for MADS box transcription factor complex formation

PubMed Central

Immink, Richard GH; Tonaco, Isabella AN; de Folter, Stefan; Shchennikova, Anna; van Dijk, Aalt DJ; Busscher-Lange, Jacqueline; Borst, Jan W; Angenent, Gerco C

2009-01-01

Background Plant MADS box proteins play important roles in a plethora of developmental processes. In order to regulate specific sets of target genes, MADS box proteins dimerize and are thought to assemble into multimeric complexes. In this study a large-scale yeast three-hybrid screen is utilized to provide insight into the higher-order complex formation capacity of the Arabidopsis MADS box family. SEPALLATA3 (SEP3) has been shown to mediate complex formation and, therefore, special attention is paid to this factor in this study. Results In total, 106 multimeric complexes were identified; in more than half of these at least one SEP protein was present. Besides the known complexes involved in determining floral organ identity, various complexes consisting of combinations of proteins known to play a role in floral organ identity specification, and flowering time determination were discovered. The capacity to form this latter type of complex suggests that homeotic factors play essential roles in down-regulation of the MADS box genes involved in floral timing in the flower via negative auto-regulatory loops. Furthermore, various novel complexes were identified that may be important for the direct regulation of the floral transition process. A subsequent detailed analysis of the APETALA3, PISTILLATA, and SEP3 proteins in living plant cells suggests the formation of a multimeric complex in vivo. Conclusions Overall, these results provide strong indications that higher-order complex formation is a general and essential molecular mechanism for plant MADS box protein functioning and attribute a pivotal role to the SEP3 'glue' protein in mediating multimerization. PMID:19243611

A review of the possible mechanisms of action of tocotrienol - a potential antiosteoporotic agent.

PubMed

Chin, Kok-Yong; Mo, Huanbiao; Soelaiman, Ima-Nirwana

2013-12-01

Osteoporosis is posing a tremendous healthcare problem globally. Much effort has been invested in finding novel antiosteoporotic agents to stop the progression of this disease. Tocotrienol, one of the isoforms of vitamin E, is poised as a potential antiosteoporotic agent. Previous studies showed that tocotrienol as a single isomer or as a mixture demonstrated both anabolic and antiresorptive effects in various rodent models of osteoporosis. In vitro experiments further demonstrated that tocotrienol could up-regulate genes related to osteoblastogenesis and modify receptor activator of nuclear factor kappa B signaling against osteoclastogenesis. Additionally, tocotrienol was also shown to be a strong 3- hydroxy-3-methyl-glutaryl-CoA reductase down-regulator with a mechanism different from that of statins. Inhibition of the mevalonate pathway affects both osteoblast and osteoclast formation in favor of the former. Tocopherol, a more commonly used isoform of vitamin E does not possess similar effects. Tocotrienol is also a potent antioxidant. It can scavenge free radicals and prevent oxidative damage on osteoblast thus promoting its survival. It may also up-regulate the antioxidant defense network in osteoclast and indirectly act against free radical signaling essential in osteoclastogenesis. The effects of tocotrienol on Wnt/β-catenin signaling essential in osteoblastogenesis have not been determined. More mechanistic studies need to be conducted to illustrate the antiosteoporotic effects of tocotrienol. Clinical trials are also required to confirm its effects in humans. In conclusion, tocotrienol demonstrates great potential as an antiosteoporotic agent and much research effort should be invested to develop it as an agent to curb osteoporosis.

Global Gene Expression Patterns and Somatic Mutations in Sporadic Intracranial Aneurysms.

PubMed

Li, Zhili; Tan, Haibin; Shi, Yi; Huang, Guangfu; Wang, Zhenyu; Liu, Ling; Yin, Cheng; Wang, Qi

2017-04-01

High-throughput sequencing technologies can expand our understanding of the pathologic basis of intracranial aneurysms (IAs). Our study was aimed to decipher the gene expression signature and genetic factors associated with IAs. We determined the gene expression levels of 3 cases of IAs by RNA sequencing. Bioinformatics analysis was conducted to identify the differentially expressed genes (DEGs) and uncover their biological function. In addition, whole genome sequencing was performed on an additional 6 cases of IAs to detect the potential somatic alterations in DEGs. Compared with the normal arterial tissue, 1709 genes were differentially expressed in IAs arterial tissue. The most significantly up-regulated gene and down-regulated gene, H19 and HIST1H3J, may be essential for tumorigenesis of IAs. Hub protein of IKBKG in protein-protein interaction network was probably involved in the inflammation process in aneurysms. Another 2 hub proteins, ACTB and MKI67IP, as well as up-regulated genes, might be abnormally activated in aneurysms and involved in the pathogenesis of IAs. Further whole genome sequencing and filtering yielded 4 candidate somatic single nucleotide variants including MUC3B, and BLM may be involved in the pathogenesis of IAs. Even though, our results do not support the hypothesis of somatic mutations occurred in the DEGs. Two-dimensional genomic data from transcriptome and whole genome sequencing indicated that no somatic mutations occurred in DEGs. In addition, 3 DEGs (IKBKG, ACTB, and MKI67IP) and 2 mutant genes (MUC3B and BLM) were essential in IAs. Copyright © 2017 Elsevier Inc. All rights reserved.

Involvement of miR17 pathway in glucocorticoid-induced cell death in pediatric acute lymphoblastic leukemia.

PubMed

Harada, Masako; Pokrovskaja-Tamm, Katja; Söderhäll, Stefan; Heyman, Mats; Grander, Dan; Corcoran, Martin

2012-10-01

Analysis of the microRNA transcriptome following dexa- methasone treatment of the acute lymphocytic leukemia (ALL) cell line RS4;11 showed a global down-regulation of microRNA levels. MIR17HG was rapidly down-regulated following treatment, with chromatin immunoprecipitation (ChIP) analysis demonstrating the promoter to be a direct target of glucocorticoid (GC)-transcriptional repression and revealing the miR17-92 cluster as a prime target for dexamethasone-induced repression. The loss of miR17 family expression and concomitant increases in the miR17 target Bim occurred in an additional ALL cell line SUP-B15 but not in the dexamethasone-resistant REH. Alteration of miR17 levels through up-regulation or inhibition resulted in an decrease and increase, respectively, in Bim protein levels and dexamethasone-induced cell death. Primary ex vivo ALL cells that underwent apoptosis induced by dexamethasone also down-regulated miR17 levels. Thus, down-regulation of miR17 plays an important role in glucocorticoid-induced cell death suggesting that targeting miR17 may improve the current ALL combination therapy.

The effect of strategies, goals and stimulus material on the neural mechanisms of emotion regulation: A meta-analysis of fMRI studies.

PubMed

Morawetz, Carmen; Bode, Stefan; Derntl, Birgit; Heekeren, Hauke R

2017-01-01

Emotion regulation comprises all extrinsic and intrinsic control processes whereby people monitor, evaluate and modify the occurrence, intensity and duration of emotional reactions. Here we sought to quantitatively summarize the existing neuroimaging literature to investigate a) whether different emotion regulation strategies are based on different or the same neural networks; b) which brain regions in particular support the up- and down-regulation of emotions, respectively; and c) to which degree the neural networks realising emotion regulation depend on the stimulus material used to elicit emotions. The left ventrolateral prefrontal cortex (VLPFC), the anterior insula and the supplementary motor area were consistently activated independent of the regulation strategy. VLPFC and posterior cingulate cortex were the main regions consistently found to be recruited during the up-regulation as well as the down-regulation of emotion. The down-regulation compared to the up-regulation of emotions was associated with more right-lateralized activity while up-regulating emotions more strongly modulated activity in the ventral striatum. Finally, the process of emotion regulation appeared to be unaffected by stimulus material. Copyright © 2016 Elsevier Ltd. All rights reserved.

Polypyrimidine tract-binding protein 1-mediated down-regulation of ATG10 facilitates metastasis of colorectal cancer cells.

PubMed

Jo, Yoon Kyung; Roh, Seon Ae; Lee, Heejin; Park, Na Yeon; Choi, Eun Sun; Oh, Ju-Hee; Park, So Jung; Shin, Ji Hyun; Suh, Young-Ah; Lee, Eun Kyung; Cho, Dong-Hyung; Kim, Jin Cheon

2017-01-28

Autophagy plays complex roles in tumor initiation and development, and the expression of autophagy-related genes (ATGs) is differentially regulated in various cancer cells, depending on their environment. In this study, we analyzed the expressional relationship between polypyrimidine tract-binding protein 1 (PTBP1) and ATG10 in metastatic colorectal cancer. PTBP1 is associated with tumor metastasis in primary colorectal tumors and colorectal cancer liver metastasis (CLM) tissues. In addition, PTPB1 directly interacts with mRNA of ATG10, and regulates ATG10 expression level in colorectal cancer cells. Ectopic expression of PTBP1 decreased ATG10 expression, whereas down-regulation of PTBP1 increased ATG10 level. In contrast to PTBP1, expression of ATG10 was decreased in CLM tissues. Knock down of ATG10 promoted cell migration and invasion of colorectal cancer cells. Moreover, depletion of ATG10 modulated epithelial-mesenchymal transition-associated proteins in colorectal cancer cells: N-cadherin, TCF-8/ZEB1, and CD44 were up-regulated, whereas E-cadherin was down-regulated. Taken together, our findings suggest that expression of ATG10 negatively regulated by PTBP1 is associated with metastasis of colorectal cancer cells. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Molecular Genetic Traits Influencing Maize Endosperm Development and Value: Closeout Report for DOE Grant DE-FG02-96ER20242

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

Brian A. Larkins

2012-09-12

Development of the endosperm in cereal grasses entails different phases characterized by cell division, endoreduplication, accumulation of storage metabolites and cell death, which need to be carried out in an orderly fashion. While correct regulation of the cell cycle plays an essential role in endosperm development, the key regulatory factors and how the cell cycle interfaces with other pathways in this developmental context are largely unknown. We investigated the cyclin-dependent kinase (CDK)-retinoblastoma pathway and how it controls the cell cycle and coordinates it with other processes during maize endosperm development. Retinoblastoma-related (RBR) proteins may be inactivated through CDK-mediated phosphorylation, butmore » the identity of the responsible kinase in maize is unknown. We have previously shown that down-regulation of CDKA;1 severely inhibits the endoreduplication cell cycle and suggested that CDK may be an up-stream regulator of the retinoblastoma pathway. We discovered two types of maize RBR genes, RBR1 and RBR3, which differ in terms of structure, regulation and function. Phylogenetic analyses indicate that these genes may be distinctive features of the Poaceae. We found that RBR3 plays a positive rather than a negative role in DNA replication, cell transformation, and the expression of the minichromosome maintenance (MCM)2-7 family of DNA replication factors. These features are a paradigm shift in RBR gene function and appear to be unique within the RBR gene family. They suggest the existence in maize and related cereal crops of specific RBR/E2F-dependent pathways impinging on the cell cycle and development. RBR1 was down-regulated in transgenic endosperm using RNAi approaches. This resulted in the de-repression of a number of down-stream E2F targets, including RBR3, the MCM2-7 gene family, DNA methyltransferase (MET)1, CDKB;1, and the recently identified RBR4 gene. It also increased endosperm ploidy levels, stimulated the production of a larger number of cells, reduced the average cell size, and promoted programmed cell death. To test whether CDKA;1 inhibits RBR1 (through phosphorylation) in the pathway that leads to DNA synthesis and endoreduplication, the two CDKA;1 and RBR1 down-regulated mutants were crossed and their progeny analyzed. Our results indicate that CDKA;1 controls endoreduplication through an RBR1-dependent pathway. However, the ability of RBR1 to repress gene expression programs is independent from CDKA1, suggesting the presence of two differently regulated RBR1 activities in developing endosperm. One type of RBR1 activity controls E2F-dependent gene expression and is largely independent from CDKA;1, while another suppresses endoreduplication and can be inhibited by CDKA;1. In addition, RBR1 is part of a regulatory feedback loop that impinges on CDK activity. Together, these results indicate that the CDKA;1-RBR1 pathway integrates and controls different processes associated with endosperm development. Genome-wide analyses of the transcriptome, metabolome, and epigenetic mechanisms to understand how the cell cycle is coordinated with other pathways at a systems biology level are currently underway.« less

Associations of Child and Adolescent Mastery Motivation and Self-Regulation With Adult Outcomes: A Longitudinal Study of Individuals With Down Syndrome.

PubMed

Gilmore, Linda; Cuskelly, Monica

2017-05-01

This 20-year prospective longitudinal study focuses on the contribution of mastery motivation and self-regulation to adult outcomes for individuals with Down syndrome. In earlier phases of the research, 25 participants completed measures of cognitive ability, mastery motivation and self-regulation in childhood (4 to 6 years) and adolescence (11 to 15 years). In the adult phase reported here, self-determination and adaptive behavior were assessed in 21 of the original participants at age 23 to 26 years. Mastery motivation and self-regulation made unique contributions to adult outcomes, over and above the effects of cognitive ability. The findings provide powerful evidence about the important role of child and adolescent mastery motivation and self-regulation for the adult lives of individuals with Down syndrome.

Microarray-based gene expression profiling to elucidate effectiveness of fermented Codonopsis lanceolata in mice.

PubMed

Choi, Woon Yong; Kim, Ji Seon; Park, Sung Jin; Ma, Choong Je; Lee, Hyeon Yong

2014-04-08

In this study, the effect of Codonopsis lanceolata fermented by lactic acid on controlling gene expression levels related to obesity was observed in an oligonucleotide chip microarray. Among 8170 genes, 393 genes were up regulated and 760 genes were down regulated in feeding the fermented C. lanceolata (FCL). Another 374 genes were up regulated and 527 genes down regulated without feeding the sample. The genes were not affected by the FCL sample. It was interesting that among those genes, Chytochrome P450, Dmbt1, LOC76487, and thyroid hormones, etc., were mostly up or down regulated. These genes are more related to lipid synthesis. We could conclude that the FCL possibly controlled the gene expression levels related to lipid synthesis, which resulted in reducing obesity. However, more detailed protein expression experiments should be carried out.

Prostaglandin E2 mediates growth arrest in NFS-60 cells by down-regulating interleukin-6 receptor expression.

PubMed

de Silva, Kumudika I; Daud, Asif N; Deng, JiangPing; Jones, Stephen B; Gamelli, Richard L; Shankar, Ravi

2003-02-15

Interleukin-6 (IL-6), a potent myeloid mitogen, and the immunosuppressive prostanoid prostaglandin E2 (PGE2) are elevated following thermal injury and sepsis. We have previously demonstrated that bone marrow myeloid commitment shifts toward monocytopoiesis and away from granulocytopoiesis during thermal injury and sepsis and that PGE2 plays a central role in this alteration. Here we investigated whether PGE2 can modulate IL-6-stimulated growth in the promyelocytic cell line, NFS-60, by down-regulating IL-6 receptor (IL-6r) expression. Exposure of NFS-60 cells to PGE2 suppressed IL-6-stimulated proliferation as well as IL-6r expression. Receptor down-regulation is functionally significant since IL-6-induced signal transduction through activators of transcription (STAT)-3 is also decreased. Down-regulation of IL-6r correlated with the ability of PGE2 to arrest cells in the G0/G1 phase of the cell cycle. PGE2 appears to signal through EP2 receptors. Butaprost (EP2 agonist) but not sulprostone (EP3 agonist) inhibited IL-6-stimulated proliferation. In addition, an EP2 antagonist (AH6809) alleviated the anti-proliferative effects of PGE2. NFS-60 cells express predominantly EP2 and EP4 receptors. While PGE2 down-regulated both the IL-6r protein and mRNA expression, it had no influence on EP2 or EP4 mRNA expression. The present study demonstrates that PGE2 is a potent down-regulator of IL-6r expression and thus may provide a mechanistic explanation for the granulocytopenia seen in thermal injury and sepsis.

Fulvestrant (ICI 182,780) down-regulates androgen receptor expression and diminishes androgenic responses in LNCaP human prostate cancer cells.

PubMed

Bhattacharyya, Rumi S; Krishnan, Aruna V; Swami, Srilatha; Feldman, David

2006-06-01

The androgen receptor (AR) plays a key role in the development and progression of prostate cancer. Targeting the AR for down-regulation would be a useful strategy for treating prostate cancer, especially hormone-refractory or androgen-independent prostate cancer. In the present study, we showed that the antiestrogen fulvestrant [ICI 182,780 (ICI)] effectively suppressed AR expression in several human prostate cancer cells, including androgen-independent cells. In LNCaP cells, ICI (10 micromol/L) treatment decreased AR mRNA expression by 43% after 24 hours and AR protein expression by approximately 50% after 48 hours. We further examined the mechanism of AR down-regulation by ICI in LNCaP cells. ICI did not bind to the T877A-mutant AR present in the LNCaP cells nor did it promote proteasomal degradation of the AR. ICI did not affect AR mRNA or protein half-life. However, ICI decreased the activity of an AR promoter-luciferase reporter plasmid transfected into LNCaP cells, suggesting a direct repression of AR gene transcription. As a result of AR down-regulation by ICI, androgen induction of prostate-specific antigen mRNA and protein expression were substantially attenuated. Importantly, LNCaP cell proliferation was significantly inhibited by ICI treatment. Following 6 days of ICI treatment, a 70% growth inhibition was seen in androgen-stimulated LNCaP cells. These data show that the antiestrogen ICI is a potent AR down-regulator that causes significant inhibition of prostate cancer cell growth. Our study suggests that AR down-regulation by ICI would be an effective strategy for the treatment of all prostate cancer, especially AR-dependent androgen-independent prostate cancer.

Metabolic regulator Fnip1 is crucial for iNKT lymphocyte development

PubMed Central

Park, Heon; Tsang, Mark; Iritani, Brian M.; Bevan, Michael J.

2014-01-01

Folliculin-interacting protein 1 (Fnip1) is an adaptor protein that physically interacts with AMPK, an energy-sensing kinase that stimulates mitochondrial biogenesis and autophagy in response to low ATP, while turning off energy consumption mediated by mammalian target of rapamycin. Previous studies with Fnip1-null mice revealed that Fnip1 is essential for pre–B-cell development. Here we report a critical role of Fnip1 in invariant natural killer T (iNKT) cell development. Thymic iNKT development in Fnip1−/− mice was arrested at stage 2 (NK1.1−CD44+) but development of CD4, CD8, γδ T-cell, and NK cell lineages proceeded normally. Enforced expression of a Vα14Jα18 iNKT TCR transgene or loss of the proapoptotic protein Bim did not rescue iNKT cell maturation in Fnip1−/− mice. Whereas most known essential transcription factors for iNKT cell development were represented normally, Fnip1−/− iNKT cells failed to down-regulate Promyelocytic leukemia zinc finger compared with their WT counterparts. Moreover, Fnip1−/− iNKT cells contained hyperactive mTOR and reduced mitochondrial number despite lower ATP levels, resulting in increased sensitivity to apoptosis. These results indicate that Fnip1 is vital for iNKT cell development by maintaining metabolic homeostasis in response to metabolic stress. PMID:24785297

Uterine Deletion of Gp130 or Stat3 Shows Implantation Failure with Increased Estrogenic Responses

PubMed Central

Sun, Xiaofei; Bartos, Amanda; Whitsett, Jeffrey A.

2013-01-01

Leukemia inhibitory factor (LIF), a downstream target of estrogen, is essential for implantation in mice. LIF function is thought to be mediated by its binding to LIF receptor (LIFR) and recruitment of coreceptor GP130 (glycoprotein 130), and this receptor complex then activates signal transducer and activator of transcription (STAT)1/3. However, the importance of LIFR and GP130 acting via STAT3 in implantation remains uncertain, because constitutive inactivation of Lifr, Gp130, or Stat3 shows embryonic lethality in mice. To address this issue, we generated mice with conditional deletion of uterine Gp130 or Stat3 and show that both GP130 and STAT3 are critical for uterine receptivity and implantation. Implantation failure in these deleted mice is associated with higher uterine estrogenic responses prior to the time of implantation. These heightened estrogenic responses are not due to changes in ovarian hormone levels or expression of their nuclear receptors. In the deleted mice, estrogen-responsive gene, Lactoferrin (Ltf), and Mucin 1 protein, were up-regulated in the uterus. In addition, progesterone-responsive genes, Hoxa10 and Indian hedgehog (Ihh), were markedly down-regulated in STAT3-inactivated uteri. These changes in uteri of deleted mice were reflected by the failure of differentiation of the luminal epithelium, which is essential for blastocyst attachment. PMID:23885093

HIV-1 Nef-induced Down-Regulation of MHC Class I Requires AP-1 and Clathrin but Not PACS-1 and Is Impeded by AP-2

PubMed Central

Lubben, Nienke B.; Sahlender, Daniela A.; Motley, Alison M.; Lehner, Paul J.; Benaroch, Philippe

2007-01-01

Major histocompatibility complex class I is down-regulated from the surface of human immunodeficiency virus (HIV)-1-infected cells by Nef, a virally encoded protein that is thought to reroute MHC-I to the trans-Golgi network (TGN) in a phosphofurin acidic cluster sorting protein (PACS) 1, adaptor protein (AP)-1, and clathrin-dependent manner. More recently, an alternative model has been proposed, in which Nef uses AP-1 to direct MHC-I to endosomes and lysosomes. Here, we show that knocking down either AP-1 or clathrin with small interfering RNA inhibits the down-regulation of HLA-A2 (an MHC-I isotype) by Nef in HeLa cells. However, knocking down PACS-1 has no effect, not only on Nef-induced down-regulation of HLA-A2 but also on the localization of other proteins containing acidic cluster motifs. Surprisingly, knocking down AP-2 actually enhances Nef activity. Immuno-electron microscopy labeling of Nef-expressing cells indicates that HLA-A2 is rerouted not to the TGN, but to endosomes. In AP-2–depleted cells, more of the HLA-A2 localizes to the inner vesicles of multivesicular bodies. We propose that depleting AP-2 potentiates Nef activity by altering the membrane composition and dynamics of endosomes and causing increased delivery of HLA-A2 to a prelysosomal compartment. PMID:17581864

Alterations in expression of imprinted genes from the H19/IGF2 loci in a multigenerational model of intrauterine growth restriction (IUGR).

PubMed

Gonzalez-Rodriguez, Pablo; Cantu, Jessica; O'Neil, Derek; Seferovic, Maxim D; Goodspeed, Danielle M; Suter, Melissa A; Aagaard, Kjersti M

2016-05-01

The H19/IGF2 imprinted loci have attracted recent attention because of their role in cellular differentiation and proliferation, heritable gene regulation, and in utero or early postnatal growth and development. Expression from the imprinted H19/IGF2 locus involves a complex interplay of 3 means of epigenetic regulation: proper establishment of DNA methylation, promoter occupancy of CTCF, and expression of microRNA-675. We have demonstrated previously in a multigenerational rat model of intrauterine growth restriction the epigenetic heritability of adult metabolic syndrome in a F2 generation. We have further demonstrated abrogation of the F2 adult metabolic syndrome phenotype with essential nutrient supplementation of intermediates along the 1-carbon pathway and shown that alterations in the metabolome precede the adult onset of metabolic syndrome. The upstream molecular and epigenomic mediators underlying these observations, however, have yet to be elucidated fully. In the current study, we sought to characterize the impact of the intrauterine growth-restricted lineage and essential nutrient supplementation on both levels and molecular mediators of H19 and IGF2 gene expression in the F2 generation. F2 intrauterine growth-restricted and sham lineages were obtained by exposing P1 (grandmaternal) pregnant dams to bilateral uterine artery ligation or sham surgery at gestational day 19.5. F1 pups were allocated to the essential nutrient supplemented or control diet at postnatal day 21, and bred at 6-7 weeks of age. Hepatic tissues from the resultant F2 offspring at birth and at weaning (day 21) were obtained. Bisulfite modification and sequencing was employed for methylation analysis. H19 and IGF2 expression was measured by quantitative polymerase chain reaction. Promoter occupancy was quantified by the use of chromatin immunoprecipitation, or ChIP, against CTCF insulator proteins. Growth-restricted F2 on control diet demonstrated significant down-regulation in H19 expression compared with sham lineage (0.7831 vs 1.287; P < .05); however, essential nutrient supplementation diet abrogates this difference (4.995 vs 5.100; P > .05). Conversely, Igf2 was up-regulated by essential nutrient supplemented diet on the sham lineage (2.0 fold, P = .01), an effect that was not observed in the growth restricted offspring. A significant differential methylation was observed in the promoter region of region H19 among the intrauterine growth-restricted lineage (18% vs 25%; P < .05) on a control diet, whereas the essential nutrient supplemented diet was alternately associated with hypermethylation in both lineages (sham: 50%; intrauterine growth restriction: 84%, P < .05). Consistent with essential nutrient supplementation impacting the epigenome, a decrease of CTCF promoter occupancy was observed in CTCF4 of the growth restricted lineage (2.45% vs 0.56%; P < .05) on the control diet, an effect that was repressed with essential nutrient supplementation. Heritable growth restriction is associated with changes in H19 gene expression; these changes are reversible with diet supplementation to favorably impact adult metabolic syndrome. Copyright © 2016. Published by Elsevier Inc.

Spatiotemporal Analysis of Copper Homeostasis in Populus trichocarpa Reveals an Integrated Molecular Remodeling for a Preferential Allocation of Copper to Plastocyanin in the Chloroplasts of Developing Leaves1[C][W][OA

PubMed Central

Ravet, Karl; Danford, Forest L.; Dihle, Alysha; Pittarello, Marco; Pilon, Marinus

2011-01-01

Plastocyanin, which requires copper (Cu) as a cofactor, is an electron carrier in the thylakoid lumen and essential for photoautotrophic growth of plants. The Cu microRNAs, which are expressed during Cu deprivation, down-regulate several transcripts that encode for Cu proteins. Since plastocyanin is not targeted by the Cu microRNAs, a cofactor economy model has been proposed in which plants prioritize Cu for use in photosynthetic electron transport. However, defects in photosynthesis are classic symptoms of Cu deprivation, and priorities in Cu cofactor delivery have not been determined experimentally. Using hydroponically grown Populus trichocarpa (clone Nisqually-1), we have established a physiological and molecular baseline for the response to Cu deficiency. An integrated analysis showed that Cu depletion strongly reduces the activity of several Cu proteins including plastocyanin, and consequently, photosynthesis and growth are decreased. Whereas plastocyanin mRNA levels were only mildly affected by Cu depletion, this treatment strongly affected the expression of other Cu proteins via Cu microRNA-mediated transcript down-regulation. Polyphenol oxidase was newly identified as Cu regulated and targeted by a novel Cu microRNA, miR1444. Importantly, a spatiotemporal analysis after Cu resupply to previously depleted plants revealed that this micronutrient is preferentially allocated to developing photosynthetic tissues. Plastocyanin and photosynthetic electron transport efficiency were the first to recover after Cu addition, whereas recovery of the other Cu-dependent activities was delayed. Our findings lend new support to the hypothesis that the Cu microRNAs serve to mediate a prioritization of Cu cofactor use. These studies also highlight poplar as an alternative sequenced model for spatiotemporal analyses of nutritional homeostasis. PMID:21941002

MafA is a Key Molecule in Glucose and Energy Balance in the Central Nervous System and Peripheral Organs

PubMed Central

Tsuchiya, Mariko; Tsuchiya, Ken; Yasuda, Kazuki; Fujita, Mikiko; Takinishi, Akira; Furukawa, Maiko; Nitta, Kosaku; Maeda, Atsushi

2011-01-01

MafA is a strong transactivator of insulin in pancreatic β cells. Elucidating the profile of MafA action in organs other than the pancreas is essential. We established an mRNA interference technique that modifies the level of target mRNAs in mice in vivo. After rapidly injecting MafA-siRNA, the resulting changes in the gene profile were analyzed using a microarray system. Significant suppression of the MafA mRNA levels was observed in the pancreas, liver, adipose tissue, and brain of siRNA-injected mice. As we reported previously, the down-regulation of insulin mRNA and adipocytokines was observed in the pancreas, and MafA siRNA caused alterations in the expressions of genes related to lipid metabolism and cell growth in the liver, and the attenuation of cell differentiation in cultured adipocytes. In addition to the effects on these organs, MafA expression was immunohistochemically detected in the brain in our preliminary data, and the expression level in siRNA-treated mice was significantly suppressed. The expressions of the affected genes were distinct, including growth hormone, vasopressin, hypocretin, and pro-melanin-concentrating hormone, were almost completely down-regulated (to ~1/100). These results suggested that MafA is likely involved in the regulation of hormonal systems related to glucose metabolism, and MafA is likely positioned near the beginning of the cascade or may influence the expressions of the above-mentioned genes in coordination with other factors in brain tissue. Taken together, the findings in this study suggested that MafA functions as a transcription factor with distinct activities in each organ and is cross-linked in several organs. PMID:23675216

Transcriptional responses of Acropora hyacinthus embryo under the benzo(a)pyrene stress by deep sequencing.

PubMed

Xiao, Rong; Zhou, Hailong; Chen, Chien-Min; Cheng, Huamin; Li, Hongwu; Xie, Jia; Zhao, Hongwei; Han, Qian; Diao, Xiaoping

2018-04-24

Coral embryos are a critical and sensitive period for the early growth and development of coral. Benzo(a)pyrene (BaP) is widely distributed in the ocean and has strong toxicity, but there is little information on the toxic effects to coral embryos exposed to this widespread environmental contaminant. Thus, in this study, we utilized the Illumina Hiseq™ 4000 platform to explore the gene response of Acropora hyacinthus embryos under the BaP stress. A total of 130,042 Unigenes were obtained and analyzed, and approximately 37.67% of those matched with sequences from four different species. In total, 2606 Unigenes were up-regulated, and 3872 Unigenes were down-regulated. After Gene Ontology (GO) annotation, the results show that the "cellular process" and "metabolic process" were leading in the category of biological processes, which the "binding" and "catalytic activity" were the most abundant subcategories in molecular function. Based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the most differentially expressed genes (DEGs) were enriched, as well as down-regulated in the pathways of oxidative phosphorylation, metabolism of xenobiotics, immune-related genes, apoptosis and human disease genes. At the same time, 388,197 of Single-nucleotide Polymorphisms (SNPs) and 6164 of Simple Sequence Repeats (SSRs) were obtained, which can be served as the richer and more valuable SSRs molecular markers in the future. The results of this study can help to better understand the toxicological mechanism of coral embryo exposed to BaP, and it is also essential for the protection and restoration of coral reef ecosystem in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.

Loss of prostasin (PRSS8) in human bladder transitional cell carcinoma cell lines is associated with epithelial-mesenchymal transition (EMT).

PubMed

Chen, Li-Mei; Verity, Nicole J; Chai, Karl X

2009-10-22

The glycosylphosphatidylinositol (GPI)-anchored epithelial extracellular membrane serine protease prostasin (PRSS8) is expressed abundantly in normal epithelia and essential for terminal epithelial differentiation, but down-regulated in human prostate, breast, and gastric cancers and invasive cancer cell lines. Prostasin is involved in the extracellular proteolytic modulation of the epidermal growth factor receptor (EGFR) and is an invasion suppressor. The aim of this study was to evaluate prostasin expression states in the transitional cell carcinomas (TCC) of the human bladder and in human TCC cell lines. Normal human bladder tissues and TCC on a bladder cancer tissue microarray (TMA) were evaluated for prostasin expression by means of immunohistochemistry. A panel of 16 urothelial and TCC cell lines were evaluated for prostasin and E-cadherin expression by western blot and quantitative PCR, and for prostasin gene promoter region CpG methylation by methylation-specific PCR (MSP). Prostasin is expressed in the normal human urothelium and in a normal human urothelial cell line, but is significantly down-regulated in high-grade TCC and lost in 9 (of 15) TCC cell lines. Loss of prostasin expression in the TCC cell lines correlated with loss of or reduced E-cadherin expression, loss of epithelial morphology, and promoter DNA hypermethylation. Prostasin expression could be reactivated by demethylation or inhibition of histone deacetylase. Re-expression of prostasin or a serine protease-inactive variant resulted in transcriptional up-regulation of E-cadherin. Loss of prostasin expression in bladder transitional cell carcinomas is associated with epithelial-mesenchymal transition (EMT), and may have functional implications in tumor invasion and resistance to chemotherapy.

Down-regulation of Intestinal Apical Calcium Entry Channel TRPV6 by Ubiquitin E3 Ligase Nedd4-2*

PubMed Central

Zhang, Wei; Na, Tao; Wu, Guojin; Jing, Haiyan; Peng, Ji-Bin

2010-01-01

Nedd4-2 is an archetypal HECT ubiquitin E3 ligase that disposes target proteins for degradation. Because of the proven roles of Nedd4-2 in degradation of membrane proteins, such as epithelial Na+ channel, we examined the effect of Nedd4-2 on the apical Ca2+ channel TRPV6, which is involved in transcellular Ca2+ transport in the intestine using the Xenopus laevis oocyte system. We demonstrated that a significant amount of Nedd4-2 protein was distributed to the absorptive epithelial cells in ileum, cecum, and colon along with TRPV6. When co-expressed in oocytes, Nedd4-2 and, to a lesser extent, Nedd4 down-regulated the protein abundance and Ca2+ influx of TRPV6 and TRPV5, respectively. TRPV6 ubiquitination was increased, and its stability was decreased by Nedd4-2. The Nedd4-2 inhibitory effects on TRPV6 were partially blocked by proteasome inhibitor MG132 but not by the lysosome inhibitor chloroquine. The rate of TRPV6 internalization was not significantly altered by Nedd4-2. The HECT domain was essential to the inhibitory effect of Nedd4-2 on TRPV6 and to their association. The WW1 and WW2 domains interacted with TRPV6 terminal regions, and a disruption of the interactions by D204H and D376H mutations in the WW1 and WW2 domains increased TRPV6 ubiquitination and degradation. Thus, WW1 and WW2 may serve as a molecular switch to limit the ubiquitination of TRPV6 by the HECT domain. In conclusion, Nedd4-2 may regulate TRPV6 protein abundance in intestinal epithelia by controlling TRPV6 ubiquitination. PMID:20843805

Down-regulation of intestinal apical calcium entry channel TRPV6 by ubiquitin E3 ligase Nedd4-2.

PubMed

Zhang, Wei; Na, Tao; Wu, Guojin; Jing, Haiyan; Peng, Ji-Bin

2010-11-19

Nedd4-2 is an archetypal HECT ubiquitin E3 ligase that disposes target proteins for degradation. Because of the proven roles of Nedd4-2 in degradation of membrane proteins, such as epithelial Na(+) channel, we examined the effect of Nedd4-2 on the apical Ca(2+) channel TRPV6, which is involved in transcellular Ca(2+) transport in the intestine using the Xenopus laevis oocyte system. We demonstrated that a significant amount of Nedd4-2 protein was distributed to the absorptive epithelial cells in ileum, cecum, and colon along with TRPV6. When co-expressed in oocytes, Nedd4-2 and, to a lesser extent, Nedd4 down-regulated the protein abundance and Ca(2+) influx of TRPV6 and TRPV5, respectively. TRPV6 ubiquitination was increased, and its stability was decreased by Nedd4-2. The Nedd4-2 inhibitory effects on TRPV6 were partially blocked by proteasome inhibitor MG132 but not by the lysosome inhibitor chloroquine. The rate of TRPV6 internalization was not significantly altered by Nedd4-2. The HECT domain was essential to the inhibitory effect of Nedd4-2 on TRPV6 and to their association. The WW1 and WW2 domains interacted with TRPV6 terminal regions, and a disruption of the interactions by D204H and D376H mutations in the WW1 and WW2 domains increased TRPV6 ubiquitination and degradation. Thus, WW1 and WW2 may serve as a molecular switch to limit the ubiquitination of TRPV6 by the HECT domain. In conclusion, Nedd4-2 may regulate TRPV6 protein abundance in intestinal epithelia by controlling TRPV6 ubiquitination.

BMP15 suppresses progesterone production by down-regulating StAR via ALK3 in human granulosa cells.

PubMed

Chang, Hsun-Ming; Cheng, Jung-Chien; Klausen, Christian; Leung, Peter C K

2013-12-01

In addition to somatic cell-derived growth factors, oocyte-derived growth differentiation factor (GDF)9 and bone morphogenetic protein (BMP)15 play essential roles in female fertility. However, few studies have investigated their effects on human ovarian steroidogenesis, and fewer still have examined their differential effects or underlying molecular determinants. In the present study, we used immortalized human granulosa cells (SVOG) and human granulosa cell tumor cells (KGN) to compare the effects of GDF9 and BMP15 on steroidogenic enzyme expression and investigate potential mechanisms of action. In SVOG cells, neither GDF9 nor BMP15 affects the mRNA levels of P450 side-chain cleavage enzyme or 3β-hydroxysteroid dehydrogenase. However, treatment with BMP15, but not GDF9, significantly decreases steroidogenic acute regulatory protein (StAR) mRNA and protein levels as well as progesterone production. These suppressive effects, along with the induction of Sma and Mad-related protein (SMAD)1/5/8 phosphorylation, are attenuated by cotreatment with 2 different BMP type I receptor inhibitors (dorsomorphin and DMH-1). Furthermore, depletion of activin receptor-like kinase (ALK)3 using small interfering RNA reverses the effects of BMP15 on SMAD1/5/8 phosphorylation and StAR expression. Similarly, knockdown of ALK3 abolishes BMP15-induced SMAD1/5/8 phosphorylation in KGN cells. These results provide evidence that oocyte-derived BMP15 down-regulates StAR expression and decreases progesterone production in human granulosa cells, likely via ALK3-mediated SMAD1/5/8 signaling. Our findings suggest that oocyte may play a critical role in the regulation of progesterone to prevent premature luteinization during the late stage of follicle development.

Requirement of PEA3 for Transcriptional Activation of FAK Gene in Tumor Metastasis

PubMed Central

Li, Shufeng; Huang, Xiaofeng; Zhang, Dapeng; Huang, Qilai; Pei, Guoshun; Wang, Lixiang; Jiang, Wenhui; Hu, Qingang; Tan, Renxiang; Hua, Zi-Chun

2013-01-01

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase critically involved in cancer metastasis. We found an elevation of FAK expression in highly metastatic melanoma B16F10 cells compared with its less metastatic partner B16F1 cells. Down-regulation of the FAK expression by either small interfering RNA or dominant negative FAK (FAK Related Non-Kinase, FRNK) inhibited the B16F10 cell migration in vitro and invasiveness in vivo. The mechanism by which FAK activity is up-regulated in highly metastatic cells remains unclear. In this study, we reported for the first time that one of the Est family proteins, PEA3, is able to transactivate FAK expression through binding to the promoter region of FAK. We identified a PEA3-binding site between nucleotides −170 and +43 in the FAK promoter that was critical for the responsiveness to PEA3. A stronger affinity of PEA3 to this region contributed to the elevation of FAK expression in B16F10 cells. Both in vitro and in vivo knockdown of PEA3 gene successfully mimicked the cell migration and invasiveness as that induced by FAK down-regulation. The activation of the well-known upstream of PEA3, such as epidermal growth factor, JNK, and ERK can also induce FAK expression. Furthermore, in the metastatic human clinic tumor specimens from the patients with human primary oral squamous cell carcinoma, we observed a strong positive correlation among PEA3, FAK, and carcinoma metastasis. Taking together, we hypothesized that PEA3 might play an essential role in the activation of the FAK gene during tumor metastasis. PMID:24260201

Amyloid Precursor Protein (APP) Mediated Regulation of Ganglioside Homeostasis Linking Alzheimer's Disease Pathology with Ganglioside Metabolism

PubMed Central

Grimm, Marcus O. W.; Zinser, Eva G.; Grösgen, Sven; Hundsdörfer, Benjamin; Rothhaar, Tatjana L.; Burg, Verena K.; Kaestner, Lars; Bayer, Thomas A.; Lipp, Peter; Müller, Ulrike; Grimm, Heike S.; Hartmann, Tobias

2012-01-01

Gangliosides are important players for controlling neuronal function and are directly involved in AD pathology. They are among the most potent stimulators of Aβ production, are enriched in amyloid plaques and bind amyloid beta (Aβ). However, the molecular mechanisms linking gangliosides with AD are unknown. Here we identified the previously unknown function of the amyloid precursor protein (APP), specifically its cleavage products Aβ and the APP intracellular domain (AICD), of regulating GD3-synthase (GD3S). Since GD3S is the key enzyme converting a- to b-series gangliosides, it therefore plays a major role in controlling the levels of major brain gangliosides. This regulation occurs by two separate and additive mechanisms. The first mechanism directly targets the enzymatic activity of GD3S: Upon binding of Aβ to the ganglioside GM3, the immediate substrate of the GD3S, enzymatic turnover of GM3 by GD3S was strongly reduced. The second mechanism targets GD3S expression. APP cleavage results, in addition to Aβ release, in the release of AICD, a known candidate for gene transcriptional regulation. AICD strongly down regulated GD3S transcription and knock-in of an AICD deletion mutant of APP in vivo, or knock-down of Fe65 in neuroblastoma cells, was sufficient to abrogate normal GD3S functionality. Equally, knock-out of the presenilin genes, presenilin 1 and presenilin 2, essential for Aβ and AICD production, or of APP itself, increased GD3S activity and expression and consequently resulted in a major shift of a- to b-series gangliosides. In addition to GD3S regulation by APP processing, gangliosides in turn altered APP cleavage. GM3 decreased, whereas the ganglioside GD3, the GD3S product, increased Aβ production, resulting in a regulatory feedback cycle, directly linking ganglioside metabolism with APP processing and Aβ generation. A central aspect of this homeostatic control is the reduction of GD3S activity via an Aβ-GM3 complex and AICD-mediated repression of GD3S transcription. PMID:22470521

The ecdysone receptor (EcR) is a major regulator of tissue development and growth in the marine salmonid ectoparasite, Lepeophtheirus salmonis (Copepoda, Caligidae).

PubMed

Sandlund, Liv; Nilsen, Frank; Male, Rune; Dalvin, Sussie

2016-08-01

The function of the ecdysone receptor (EcR) during development and molting has been thoroughly investigated in some arthropods such as insects but rarely in crustacean copepods such as the salmon louse Lepeophtheirus salmonis (L. salmonis) (Copepoda, Caligidae). The salmon louse is an ectoparasite on Atlantic salmon that has major economical impact in aquaculture due to the cost of medical treatment methods to remove lice from the fish. Handling of salmon louse infestations is further complicated by development of resistance towards available medicines. Understanding of basic molecular biological processes in the salmon louse is essential to enable development of new tools to control the parasite. In this study, we found L. salmonis EcR (LsEcR) transcript to be present in the neuronal somata of the brain, nuclei of muscle fibres and the immature intestine of the salmon louse. Furthermore, we explored the function of LsEcR during development using RNA interference mediated knock-down and through infection trials. Our results show that knock-down of LsEcR in the salmon louse is associated with hypotrophy of several tissues, delayed development and mortality. In addition, combined knock-down of LsEcR/LsRXR resulted in molting arrest during early larval stages. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Characterization of Chlamydomonas reinhardtii Core Histones by Top-Down Mass Spectrometry Reveals Unique Algae-Specific Variants and Post-Translational Modifications.

PubMed

Khan, Aliyya; Eikani, Carlo K; Khan, Hana; Iavarone, Anthony T; Pesavento, James J

2018-01-05

The unicellular microalga Chlamydomonas reinhardtii has played an instrumental role in the development of many new fields (bioproducts, biofuels, etc.) as well as the advancement of basic science (photosynthetic apparati, flagellar function, etc.). Chlamydomonas' versatility ultimately derives from the genes encoded in its genome and the way that the expression of these genes is regulated, which is largely influenced by a family of DNA binding proteins called histones. We characterize C. reinhardtii core histones, both variants and their post-translational modifications, by chromatographic separation, followed by top-down mass spectrometry (TDMS). Because TDMS has not been previously used to study Chlamydomonas proteins, we show rampant artifactual protein oxidation using established nuclei purification and histone extraction methods. After addressing oxidation, both histones H3 and H4 are found to each have a single polypeptide sequence that is minimally acetylated and methylated. Surprisingly, we uncover a novel monomethylation at lysine 79 on histone H4 present on all observed molecules. Histone H2B and H2A are found to have two and three variants, respectively, and both are minimally modified. This study provides an updated assessment of the core histone proteins in the green alga C. reinhardtii by top-down mass spectrometry and lays the foundation for further investigation of these essential proteins.

Celecoxib can suppress expression of genes associated with PGE2 pathway in chondrocytes under inflammatory conditions.

PubMed

Sun, Tian-Wen; Wu, Zhi-Hong; Weng, Xi-Sheng

2015-01-01

This study aimed to investigate the effect of a selective cyclooxygenase-2 (COX-2) inhibitor (celecoxib) on the expression of arachidonate-associated inflammatory genes in cultured human normal chondrocytes. Normal chondrocytes were obtained from the cartilage of three different amputated patients without osteoarthritis (OA). Affymetrix Human microarray was used to assess the alterations in gene expression in three groups of cells: untreated cells (negative control group), cells treated with interleukin-1β (IL-1β) (positive control group), and cells treated with IL-1β and celecoxib. The patterns of up-regulation and down-regulation of gene expression were further validated by real-time PCR. A total of 1091 up-regulated genes and 1252 down-regulated genes were identified in the positive control group compared with the negative control group. Among them, PTGS2, ADAMTS5, PTGER2, mPTGES and PTGER4 are known to be involved in chondrocyte inflammation, while VEGFA, BCL2, TRAF1, CYR61, BMP6, DAPK1, DUSP7, IL1RN, MMP13 and TNFSF10 were reported being associated with cytokine and chemokine signaling. 189 up-regulated genes and 177 down-regulated genes were identified in the positive control group compared with intervention group. PTGS1, PTGS2, ADAMTS5, PTGER2, mPTGES and PTGER4 were among the genes down-regulated upon the treatment with celecoxib. Our results demonstrated that the OA chondrocytes are the site of active eicosanoid production. IL-1β can activate inflammation in chondrocytes and trigger the production of various proteins involved in cyclooxygenase pathway. The expression of genes corresponding to these proteins can be down-regulated by celecoxib. The findings indicate that the therapy with prostaglandin E2 (PGE2)-blocking agents may decrease the PGE2 production not only by direct inhibition of COX-2 activity, but also by down-regulating the expression of genes encoding for COX-2, microsomal prostaglandin-endoperoxide synthase 1 (mPGES-1) and prostaglandin E receptors 4 (EP4) in the articular chondrocytes.

Myeloproliferative neoplasms: JAK2 signaling pathway as a central target for therapy.

PubMed

Pasquier, Florence; Cabagnols, Xenia; Secardin, Lise; Plo, Isabelle; Vainchenker, William

2014-09-01

The discovery of the JAK2V617F mutation followed by the discovery of other genetic abnormalities allowed important progress in the understanding of the pathogenesis and management of myeloproliferative neoplasms (MPN)s. Classical Breakpoint cluster region-Abelson (BCR-ABL)-negative neoplasms include 3 main disorders: essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF). Genomic studies have shown that these disorders are more heterogeneous than previously thought with 3 main entities corresponding to different gene mutations: the JAK2 disorder, essentially due to JAK2V617F mutation, which includes nearly all PVs and a majority of ETs and PMFs with a continuum between these diseases and the myeloproliferative leukemia (MPL) and calreticulin (CALR) disorders, which include a fraction of ET and PMF. All of these mutations lead to a JAK2 constitutive activation. Murine models either with JAK2V617F or MPLW515L, but also with JAK2 or MPL germ line mutations found in hereditary thrombocytosis, have demonstrated that they are drivers of myeloproliferation. However, the myeloproliferative driver mutation is still unknown in approximately 15% of ET and PMF, but appears to also target the JAK/Signal Transducer and Activator of Transcription (STAT) pathway. However, other mutations in genes involved in epigenetics or splicing also can be present and can predate or follow mutations in signaling. They are involved either in clonal dominance or in phenotypic changes, more particularly in PMF. They can be associated with leukemic progression and might have an important prognostic value such as additional sex comb-like 1 mutations. Despite this heterogeneity, it is tempting to target JAK2 and its signaling for therapy. However in PMF, Adenosine Tri-Phosphate (ATP)-competitive JAK2 inhibitors have shown their interest, but also their important limitations. Thus, other approaches are required, which are discussed in this review. Copyright © 2014 Elsevier Inc. All rights reserved.

JAK and MPL mutations in myeloid malignancies.

PubMed

Tefferi, Ayalew

2008-03-01

The Janus family of non-receptor tyrosine kinases (JAK1, JAK2, JAK3 and tyrosine kinase 2) transduces signals downstream of type I and II cytokine receptors via signal transducers and activators of transcription (STATs). JAK3 is important in lymphoid and JAK2 in myeloid cell proliferation and differentiation. The thrombopoietin receptor MPL is one of several JAK2 cognate receptors and is essential for myelopoiesis in general and megakaryopoiesis in particular. Germline loss-of-function (LOF) JAK3 and MPL mutations cause severe combined immunodeficiency and congenital amegakaryocytic thrombocytopenia, respectively. Germline gain-of-function (GOF) MPL mutation (MPLS505N) causes familial thrombocytosis. Somatic JAK3 (e.g. JAK3A572V, JAK3V722I, JAK3P132T) and fusion JAK2 (e.g. ETV6-JAK2, PCM1-JAK2, BCR-JAK2) mutations have respectively been described in acute megakaryocytic leukemia and acute leukemia/chronic myeloid malignancies. However, current attention is focused on JAK2 (e.g. JAK2V617F, JAK2 exon 12 mutations) and MPL (e.g. MPLW515L/K/S, MPLS505N) mutations associated with myeloproliferative neoplasms (MPNs). A JAK2 mutation, primarily JAK2V617F, is invariably associated with polycythemia vera (PV). The latter mutation also occurs in the majority of patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF). MPL mutational frequency in MPNs is substantially less (<10%). In general, despite a certain degree of genotype - phenotype correlations, the prognostic relevance of harbouring one of these mutations, or their allele burden when present, remains dubious. Regardless, based on the logical assumption that amplified JAK-STAT signalling is central to the pathogenesis of PV, ET and PMF, several anti-JAK2 tyrosine kinase inhibitors have been developed and are currently being tested in humans with these disorders.

Blast transformation and fibrotic progression in polycythemia vera and essential thrombocythemia: a literature review of incidence and risk factors

PubMed Central

Cerquozzi, S; Tefferi, A

2015-01-01

Polycythemia vera (PV) and essential thrombocythemia (ET) constitute two of the three BCR-ABL1-negative myeloproliferative neoplasms and are characterized by relatively long median survivals (approximately 14 and 20 years, respectively). Potentially fatal disease complications in PV and ET include disease transformation into myelofibrosis (MF) or acute myeloid leukemia (AML). The range of reported frequencies for post-PV MF were 4.9–6% at 10 years and 6–14% at 15 years and for post-ET MF were 0.8–4.9% at 10 years and 4–11% at 15 years. The corresponding figures for post-PV AML were 2.3–14.4% at 10 years and 5.5–18.7% at 15 years and for post-ET AML were 0.7–3% at 10 years and 2.1–5.3% at 15 years. Risk factors cited for post-PV MF include advanced age, leukocytosis, reticulin fibrosis, splenomegaly and JAK2V617F allele burden and for post-ET MF include advanced age, leukocytosis, anemia, reticulin fibrosis, absence of JAK2V617F, use of anagrelide and presence of ASXL1 mutation. Risk factors for post-PV AML include advanced age, leukocytosis, reticulin fibrosis, splenomegaly, abnormal karyotype, TP53 or RUNX1 mutations as well as use of pipobroman, radiophosphorus (P32) and busulfan and for post-ET AML include advanced age, leukocytosis, anemia, extreme thrombocytosis, thrombosis, reticulin fibrosis, TP53 or RUNX1 mutations. It is important to note that some of the aforementioned incidence figures and risk factor determinations are probably inaccurate and at times conflicting because of the retrospective nature of studies and the inadvertent labeling, in some studies, of patients with prefibrotic primary MF or ‘masked' PV, as ET. Ultimately, transformation of MPN leads to poor outcomes and management remains challenging. Further understanding of the molecular events leading to disease transformation is being investigated. PMID:26565403

Transcriptomic analysis reveals the gene expression profile that specifically responds to IBA during adventitious rooting in mung bean seedlings.

PubMed

Li, Shi-Weng; Shi, Rui-Fang; Leng, Yan; Zhou, Yuan

2016-01-12

Auxin plays a critical role in inducing adventitious rooting in many plants. Indole-3-butyric acid (IBA) is the most widely employed auxin for adventitious rooting. However, the molecular mechanisms by which auxin regulate the process of adventitious rooting are less well known. The RNA-Seq data analysis indicated that IBA treatment greatly increased the amount of clean reads and the amount of expressed unigenes by 24.29 % and 27.42 % and by 4.3 % and 5.04 % at two time points, respectively, and significantly increased the numbers of unigenes numbered with RPKM = 10-100 and RPKM = 500-1000 by 13.04 % and 3.12 % and by 24.66 % and 108.2 % at two time points, respectively. Gene Ontology (GO) enrichment analysis indicated that the enrichment of down-regulated GOs was 2.87-fold higher than that of up-regulated GOs at stage 1, suggesting that IBA significantly down-regulated gene expression at 6 h. The GO functional category indicated that IBA significantly up- or down-regulated processes associated with auxin signaling, ribosome assembly and protein synthesis, photosynthesis, oxidoreductase activity and extracellular region, secondary cell wall biogenesis, and the cell wall during the development process. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment indicated that ribosome biogenesis, plant hormone signal transduction, pentose and glucuronate interconversions, photosynthesis, phenylpropanoid biosynthesis, sesquiterpenoid and triterpenoid biosynthesis, ribosome, cutin, flavonoid biosynthesis, and phenylalanine metabolism were the pathways most highly regulated by IBA. A total of 6369 differentially expressed (2-fold change > 2) unigenes (DEGs) with 3693 (58 %) that were up-regulated and 2676 (42 %) down-regulated, 5433 unigenes with 2208 (40.6 %) that were up-regulated and 3225 (59.4 %) down-regulated, and 7664 unigenes with 3187 (41.6 %) that were up-regulated and 4477 (58.4 %) down-regulated were detected at stage 1, stage 2, and between stage 1 and stage 2, respectively, suggesting that IBA treatment increased the number of DEGs. A total of 143 DEGs specifically involved in plant hormone signaling and 345 transcription factor (TF) genes were also regulated by IBA. qRT-PCR validation of the 36 genes with known functions indicated a strong correlation with the RNA-Seq data. The changes in GO functional categories, KEGG pathways, and global DEG profiling during adventitious rooting induced by IBA were analyzed. These results provide valuable information about the molecular traits of IBA regulation of adventitious rooting.

Transcriptome sequencing and de novo analysis of cytoplasmic male sterility and maintenance in JA-CMS cotton.

PubMed

Yang, Peng; Han, Jinfeng; Huang, Jinling

2014-01-01

Cytoplasmic male sterility (CMS) is the failure to produce functional pollen, which is inherited maternally. And it is known that anther development is modulated through complicated interactions between nuclear and mitochondrial genes in sporophytic and gametophytic tissues. However, an unbiased transcriptome sequencing analysis of CMS in cotton is currently lacking in the literature. This study compared differentially expressed (DE) genes of floral buds at the sporogenous cells stage (SS) and microsporocyte stage (MS) (the two most important stages for pollen abortion in JA-CMS) between JA-CMS and its fertile maintainer line JB cotton plants, using the Illumina HiSeq 2000 sequencing platform. A total of 709 (1.8%) DE genes including 293 up-regulated and 416 down-regulated genes were identified in JA-CMS line comparing with its maintainer line at the SS stage, and 644 (1.6%) DE genes with 263 up-regulated and 381 down-regulated genes were detected at the MS stage. By comparing the two stages in the same material, there were 8 up-regulated and 9 down-regulated DE genes in JA-CMS line and 29 up-regulated and 9 down-regulated DE genes in JB maintainer line at the MS stage. Quantitative RT-PCR was used to validate 7 randomly selected DE genes. Bioinformatics analysis revealed that genes involved in reduction-oxidation reactions and alpha-linolenic acid metabolism were down-regulated, while genes pertaining to photosynthesis and flavonoid biosynthesis were up-regulated in JA-CMS floral buds compared with their JB counterparts at the SS and/or MS stages. All these four biological processes play important roles in reactive oxygen species (ROS) homeostasis, which may be an important factor contributing to the sterile trait of JA-CMS. Further experiments are warranted to elucidate molecular mechanisms of these genes that lead to CMS.

Transcriptome Sequencing and De Novo Analysis of Cytoplasmic Male Sterility and Maintenance in JA-CMS Cotton

PubMed Central

Yang, Peng; Han, Jinfeng; Huang, Jinling

2014-01-01

Cytoplasmic male sterility (CMS) is the failure to produce functional pollen, which is inherited maternally. And it is known that anther development is modulated through complicated interactions between nuclear and mitochondrial genes in sporophytic and gametophytic tissues. However, an unbiased transcriptome sequencing analysis of CMS in cotton is currently lacking in the literature. This study compared differentially expressed (DE) genes of floral buds at the sporogenous cells stage (SS) and microsporocyte stage (MS) (the two most important stages for pollen abortion in JA-CMS) between JA-CMS and its fertile maintainer line JB cotton plants, using the Illumina HiSeq 2000 sequencing platform. A total of 709 (1.8%) DE genes including 293 up-regulated and 416 down-regulated genes were identified in JA-CMS line comparing with its maintainer line at the SS stage, and 644 (1.6%) DE genes with 263 up-regulated and 381 down-regulated genes were detected at the MS stage. By comparing the two stages in the same material, there were 8 up-regulated and 9 down-regulated DE genes in JA-CMS line and 29 up-regulated and 9 down-regulated DE genes in JB maintainer line at the MS stage. Quantitative RT-PCR was used to validate 7 randomly selected DE genes. Bioinformatics analysis revealed that genes involved in reduction-oxidation reactions and alpha-linolenic acid metabolism were down-regulated, while genes pertaining to photosynthesis and flavonoid biosynthesis were up-regulated in JA-CMS floral buds compared with their JB counterparts at the SS and/or MS stages. All these four biological processes play important roles in reactive oxygen species (ROS) homeostasis, which may be an important factor contributing to the sterile trait of JA-CMS. Further experiments are warranted to elucidate molecular mechanisms of these genes that lead to CMS. PMID:25372034

Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

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

Wang, Ruoxing; Guo, Yan-Lin, E-mail: yanlin.guo@usm.edu

2012-10-01

Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remainsmore » unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: Black-Right-Pointing-Pointer Inhibition of Cdks slows down mESCs proliferation. Black-Right-Pointing-Pointer mESCs display remarkable recovery capacity from short-term cell cycle interruption. Black-Right-Pointing-Pointer Short-term cell cycle interruption does not compromise mESC self-renewal. Black-Right-Pointing-Pointer Oct4 and Nanog are up-regulated via de novo synthesis by cell cycle interruption.« less

Myxedema coma in a patient with Down's syndrome.

PubMed

Bansal, Darpan; Nanda, Ashish; Gupta, Ekta; Croker, Mary; Williams, Misty L; Bacchus, Amy; Simmons, Debra; Erbland, Marcia

2006-11-01

hyroid dysfunction is common in Down's syndrome, most common being hypothyroidism. Longstanding, untreated hypothyroidism can lead to myxedema coma. Here we report a patient with Down's syndrome who presented with myxedema coma. The three essential elements for the diagnosis of myxedema coma include altered mental status, defective thermoregulation and a precipitating event or illness; all of these were present in our patient. Also, very high TSH, low T3 and T4, and the rapid response to the treatment with levothyroxine confirmed the diagnosis. Patients with Down's syndrome should have regular screening for thyroid dysfunction.

Examining the effect of down regulation under high [CO2] on the growth of soybean assimilating a semi process-based model and FACE data

NASA Astrophysics Data System (ADS)

Sakurai, G.; Iizumi, T.; Yokozawa, M.

2011-12-01

The actual impact of elevated [CO2] with the interaction of the other climatic factors on the crop growth is still debated. In many process-based crop models, the response of photosynthesis per single leaf to environmental factors is basically described using the biochemical model of Farquhar et al. (1980). However, the decline in photosynthetic enhancement known as down regulation has not been taken into account. On the other hand, the mechanisms causing photosynthetic down regulation is still unknown, which makes it difficult to include the effect of down regulation into process-based crop models. The current results of Free-air CO2 enrichment (FACE) experiments have reported the effect of down regulation under actual environments. One of the effective approaches to involve these results into future crop yield prediction is developing a semi process-based crop growth model, which includes the effect of photosynthetic down regulation as a statistical model, and assimilating the data obtained in FACE experiments. In this study, we statistically estimated the parameters of a semi process-based model for soybean growth ('SPM-soybean') using a hierarchical Baysian method with the FACE data on soybeans (Morgan et al. 2005). We also evaluated the effect of down regulation on the soybean yield in future climatic conditions. The model selection analysis showed that the effective correction to the overestimation of the Farquhar's biochemical C3 model was to reduce the maximum rate of carboxylation (Vcmax) under elevated [CO2]. However, interestingly, the difference in the estimated final crop yields between the corrected model and the non-corrected model was very slight (Fig.1a) for future projection under climate change scenario (Miroc-ESM). This was due to that the reduction in Vcmax also brought about the reduction of the base dark respiration rate of leaves. Because the dark respiration rate exponentially increases with temperature, the slight difference in base respiration rate becomes a large difference under high temperature under the future climate scenarios. In other words, if the temperature rise is very small or zero under elevated [CO2] condition, the effect of down regulation significantly appears (Fig.1b). This result suggest that further experimental data that considering high CO2 effect and high temperature effect in field conditions should be important and elaborate the model projection of the future crop yield through data assimilation method.

Regulation of IL-10 expression by upstream stimulating factor (USF-1) in glioma-associated microglia.

PubMed

Zhang, Leying; Handel, Michelle Van; Schartner, Jill M; Hagar, Aaron; Allen, Grant; Curet, Marjorie; Badie, Behnam

2007-03-01

Understanding the local CNS immune response to neoplasms is essential in the development of immune-based treatments for malignant brain tumors. Using rodent glioma models, we have recently found tumor-associated microglia/macrophages (MG/MP) to be less responsive to known MG/MP activators such as CpG, LPS and IFN-gamma. To understand the mechanism of MG/MP suppression, nuclear extracts from rodent intracranial C6 gliomas, C6 glioma-associated MG/MP, normal brain, and normal MG/MP were obtained and studied using Electrophoretic Mobility Shift Assay (EMSA). Among the nuclear factors studied (AP-1, IRF, USF-1 and Stat-1) only USF-1, which is constitutively expressed in most cells, was down-regulated in tumor-associated MG/MP, but not normal MG/MP. Because tumor-associated MG/MP had higher expression of IL-10 (but not TNF-alpha or TGF-beta), we evaluated the role of USF-1 on IL-10 expression. siRNA mediated inhibition of USF-1 expression in primary MG/MP cultures resulted in up-regulation of IL-10 mRNA but not TNF-alpha or TGF-beta. These findings suggest that USF-1 may play a role in IL-10 regulation in MG/MP in brain tumors.

Expression analysis of G Protein-Coupled Receptors in mouse macrophages.

PubMed

Lattin, Jane E; Schroder, Kate; Su, Andrew I; Walker, John R; Zhang, Jie; Wiltshire, Tim; Saijo, Kaoru; Glass, Christopher K; Hume, David A; Kellie, Stuart; Sweet, Matthew J

2008-04-29

Monocytes and macrophages express an extensive repertoire of G Protein-Coupled Receptors (GPCRs) that regulate inflammation and immunity. In this study we performed a systematic micro-array analysis of GPCR expression in primary mouse macrophages to identify family members that are either enriched in macrophages compared to a panel of other cell types, or are regulated by an inflammatory stimulus, the bacterial product lipopolysaccharide (LPS). Several members of the P2RY family had striking expression patterns in macrophages; P2ry6 mRNA was essentially expressed in a macrophage-specific fashion, whilst P2ry1 and P2ry5 mRNA levels were strongly down-regulated by LPS. Expression of several other GPCRs was either restricted to macrophages (e.g. Gpr84) or to both macrophages and neural tissues (e.g. P2ry12, Gpr85). The GPCR repertoire expressed by bone marrow-derived macrophages and thioglycollate-elicited peritoneal macrophages had some commonality, but there were also several GPCRs preferentially expressed by either cell population. The constitutive or regulated expression in macrophages of several GPCRs identified in this study has not previously been described. Future studies on such GPCRs and their agonists are likely to provide important insights into macrophage biology, as well as novel inflammatory pathways that could be future targets for drug discovery.

Deciphering the metabolic response of M ycobacterium tuberculosis to nitrogen stress

PubMed Central

Williams, Kerstin J.; Jenkins, Victoria A.; Barton, Geraint R.; Bryant, William A.; Krishnan, Nitya

2015-01-01

Summary A key component to the success of M ycobacterium tuberculosis as a pathogen is the ability to sense and adapt metabolically to the diverse range of conditions encountered in vivo, such as oxygen tension, environmental pH and nutrient availability. Although nitrogen is an essential nutrient for every organism, little is known about the genes and pathways responsible for nitrogen assimilation in M . tuberculosis. In this study we have used transcriptomics and chromatin immunoprecipitation and high‐throughput sequencing to address this. In response to nitrogen starvation, a total of 185 genes were significantly differentially expressed (96 up‐regulated and 89 down regulated; 5% genome) highlighting several significant areas of metabolic change during nitrogen limitation such as nitrate/nitrite metabolism, aspartate metabolism and changes in cell wall biosynthesis. We identify GlnR as a regulator involved in the nitrogen response, controlling the expression of at least 33 genes in response to nitrogen limitation. We identify a consensus GlnR binding site and relate its location to known transcriptional start sites. We also show that the GlnR response regulator plays a very different role in M . tuberculosis to that in non‐pathogenic mycobacteria, controlling genes involved in nitric oxide detoxification and intracellular survival instead of genes involved in nitrogen scavenging. PMID:26077160

WOX4 and WOX14 act downstream of the PXY receptor kinase to regulate plant vascular proliferation independently of any role in vascular organisation.

PubMed

Etchells, J Peter; Provost, Claire M; Mishra, Laxmi; Turner, Simon R

2013-05-01

In plants, the cambium and procambium are meristems from which vascular tissue is derived. In contrast to most plant cells, stem cells within these tissues are thin and extremely long. They are particularly unusual as they divide down their long axis in a highly ordered manner, parallel to the tangential axis of the stem. CLAVATA3-LIKE/ESR-RELATED 41 (CLE41) and PHLOEM INTERCALATED WITH XYLEM (PXY) are a multifunctional ligand-receptor pair that regulate vascular cell division, vascular organisation and xylem differentiation in vascular tissue. A transcription factor gene, WUSCHEL HOMEOBOX RELATED 4 (WOX4) has been shown to act downstream of PXY. Here we show that WOX4 acts redundantly with WOX14 in the regulation of vascular cell division, but that these genes have no function in regulating vascular organisation. Furthermore, we identify an interaction between PXY and the receptor kinase ERECTA (ER) that affects the organisation of the vascular tissue but not the rate of cell division, suggesting that cell division and vascular organisation are genetically separable. Our observations also support a model whereby tissue organisation and cell division are integrated via PXY and ER signalling, which together coordinate development of different cell types that are essential for normal stem formation.

Muramyl dipeptide (MDP) induces reactive oxygen species (ROS) generation via the NOD2/COX-2/NOX4 signaling pathway in human umbilical vein endothelial cells (HUVECs).

PubMed

Kong, Ling-Jun; Liu, Xiao-Qian; Xue, Ying; Gao, Wei; Lv, Qian-Zhou

2018-03-20

Vascular endothelium dysfunction caused by oxidative stress accelerates the pathologic process of cardiovascular diseases. NOD2, an essential receptor of innate immune system, has been demonstrated to play a critical role in atherosclerosis. Here, the aim of our study was to investigate the effect and underlying molecular mechanism of muramyl dipeptide (MDP) on NOX4-mediated ROS generation in human umbilical vein endothelial cells (HUVECs). 2,7-dichlorofluorescein diacetate staining was to measure the intracellular ROS level and showed MDP promoted ROS production in a time- and dose-dependent manner. The mRNA and protein levels of NOX4 and COX-2 were detected by real-time PCR and western blot. Small interfering RNA (siRNA) was used to silence NOD2 or COX-2 gene expression and investigate the mechanism of NOD2-mediated signaling pathway in HUVECs. Data showed that MDP induced NOX4 and COX-2 expression in a time- and dose-dependent manner. NOD2 knock-down suppressed up-regulation of COX-2 and NOX4 in HUVECs treated with MDP. Furthermore, silence of COX-2 in HUVECs down-regulated the NOX4 expression after MDP stimulation. Collectively, we indicated that NOD2 played a leading role in MDP-induced COX-2/NOX4/ROS signaling pathway in HUVECs, which was a novel regulatory mechanism in the progress of ROS generation.

Silencing CAFFEOYL SHIKIMATE ESTERASE Affects Lignification and Improves Saccharification in Poplar.

PubMed

Saleme, Marina de Lyra Soriano; Cesarino, Igor; Vargas, Lívia; Kim, Hoon; Vanholme, Ruben; Goeminne, Geert; Van Acker, Rebecca; Fonseca, Fernando Campos de Assis; Pallidis, Andreas; Voorend, Wannes; Junior, José Nicomedes; Padmakshan, Dharshana; Van Doorsselaere, Jan; Ralph, John; Boerjan, Wout

2017-11-01

Caffeoyl shikimate esterase (CSE) was recently shown to play an essential role in lignin biosynthesis in Arabidopsis ( Arabidopsis thaliana ) and later in Medicago truncatula However, the general function of this enzyme was recently questioned by the apparent lack of CSE activity in lignifying tissues of different plant species. Here, we show that down-regulation of CSE in hybrid poplar ( Populus tremula × Populus alba ) resulted in up to 25% reduced lignin deposition, increased levels of p -hydroxyphenyl units in the lignin polymer, and a relatively higher cellulose content. The transgenic trees were morphologically indistinguishable from the wild type. Ultra-high-performance liquid chromatography-mass spectrometry-based phenolic profiling revealed a reduced abundance of several oligolignols containing guaiacyl and syringyl units and their corresponding hydroxycinnamaldehyde units, in agreement with the reduced flux toward coniferyl and sinapyl alcohol. These trees accumulated the CSE substrate caffeoyl shikimate along with other compounds belonging to the metabolic classes of benzenoids and hydroxycinnamates. Furthermore, the reduced lignin amount combined with the relative increase in cellulose content in the CSE down-regulated lines resulted in up to 62% more glucose released per plant upon limited saccharification when no pretreatment was applied and by up to 86% and 91% when acid and alkaline pretreatments were used. Our results show that CSE is not only important for the lignification process in poplar but is also a promising target for the development of improved lignocellulosic biomass crops for sugar platform biorefineries. © 2017 American Society of Plant Biologists. All Rights Reserved.

Negative Factor from SIV Binds to the Catalytic Subunit of the V-ATPase to Internalize CD4 and to Increase Viral Infectivity

PubMed Central

Mandic, Robert; Fackler, Oliver T.; Geyer, Matthias; Linnemann, Thomas; Zheng, Yong-Hui; Peterlin, B. Matija

2001-01-01

The accessory protein negative factor (Nef) from human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) is required for optimal viral infectivity and the progression to acquired immunodeficiency syndrome (AIDS). Nef interacts with the endocytic machinery, resulting in the down-regulation of cluster of differentiation antigen 4 (CD4) and major histocompatibility complex class I (MHCI) molecules on the surface of infected cells. Mutations in the C-terminal flexible loop of Nef result in a lower rate of internalization by this viral protein. However, no loop-dependent binding of Nef to adaptor protein-2 (AP-2), which is the adaptor protein complex that is required for the internalization of proteins from the plasma membrane, could be demonstrated. In this study we investigated the relevance of different motifs in Nef from SIVmac239 for its internalization, CD4 down-regulation, binding to components of the trafficking machinery, and viral infectivity. Our data suggest that the binding of Nef to the catalytic subunit H of the vacuolar membrane ATPase (V-ATPase) facilitates its internalization. This binding depends on the integrity of the whole flexible loop. Subsequent studies on Nef mutant viruses revealed that the flexible loop is essential for optimal viral infectivity. Therefore, our data demonstrate how Nef contacts the endocytic machinery in the absence of its direct binding to AP-2 and suggest an important role for subunit H of the V-ATPase in viral infectivity. PMID:11179428

Silencing CAFFEOYL SHIKIMATE ESTERASE Affects Lignification and Improves Saccharification in Poplar1[OPEN

PubMed Central

2017-01-01

Caffeoyl shikimate esterase (CSE) was recently shown to play an essential role in lignin biosynthesis in Arabidopsis (Arabidopsis thaliana) and later in Medicago truncatula. However, the general function of this enzyme was recently questioned by the apparent lack of CSE activity in lignifying tissues of different plant species. Here, we show that down-regulation of CSE in hybrid poplar (Populus tremula × Populus alba) resulted in up to 25% reduced lignin deposition, increased levels of p-hydroxyphenyl units in the lignin polymer, and a relatively higher cellulose content. The transgenic trees were morphologically indistinguishable from the wild type. Ultra-high-performance liquid chromatography-mass spectrometry-based phenolic profiling revealed a reduced abundance of several oligolignols containing guaiacyl and syringyl units and their corresponding hydroxycinnamaldehyde units, in agreement with the reduced flux toward coniferyl and sinapyl alcohol. These trees accumulated the CSE substrate caffeoyl shikimate along with other compounds belonging to the metabolic classes of benzenoids and hydroxycinnamates. Furthermore, the reduced lignin amount combined with the relative increase in cellulose content in the CSE down-regulated lines resulted in up to 62% more glucose released per plant upon limited saccharification when no pretreatment was applied and by up to 86% and 91% when acid and alkaline pretreatments were used. Our results show that CSE is not only important for the lignification process in poplar but is also a promising target for the development of improved lignocellulosic biomass crops for sugar platform biorefineries. PMID:28878037

Disrupted SOX10 function causes spongiform neurodegeneration in gray tremor mice

PubMed Central

Anderson, Sarah R.; Lee, Inyoul; Ebeling, Christine; Stephenson, Dennis A.; Schweitzer, Kelsey M.; Baxter, David; Moon, Tara M.; LaPierre, Sarah; Jaques, Benjamin; Silvius, Derek; Wegner, Michael; Hood, Leroy E.; Carlson, George; Gunn, Teresa M.

2014-01-01

Mice homozygous for the gray tremor (gt) mutation have a pleiotropic phenotype that includes pigmentation defects, megacolon, whole body tremors, sporadic seizures, hypo- and dysmyelination of the CNS and PNS, vacuolation of the CNS, and early death. Vacuolation similar to that caused by prions was originally reported to be transmissible, but subsequent studies showed the inherited disease was not infectious. The gt mutation mapped to distal mouse chromosome 15, to the same region as Sox10, which encodes a transcription factor with essential roles in neural crest survival and differentiation. As dominant mutations in mouse or human SOX10 cause white spotting and intestinal aganglionosis, we screened the Sox10 coding region for mutations in gt/gt DNA. An adenosine to guanine transversion was identified in exon 2 that changes a highly conserved glutamic acid residue in the SOX10 DNA binding domain to glycine. This mutant allele was not seen in wildtype mice, including the related GT/Le strain, and failed to complement a Sox10 null allele. Gene expression analysis revealed significant down-regulation of genes involved in myelin lipid biosynthesis pathways in gt/gt brains. Knockout mice for some of these genes develop CNS vacuolation and/or myelination defects, suggesting that their down-regulation may contribute to these phenotypes in gt mutants and could underlie the neurological phenotypes associated with Peripheral demyelinating neuropathy-Central dysmyelinating leukodystrophy-Waardenburg syndrome-Hirschsprung (PCWH) disease, caused by mutations in human SOX10. PMID:25399070

Betacellulin induces Slug-mediated down-regulation of E-cadherin and cell migration in ovarian cancer cells

PubMed Central

Zhao, Jianfang; Klausen, Christian; Qiu, Xin; Cheng, Jung-Chien; Chang, Hsun-Ming; Leung, Peter C.K.

2016-01-01

Epithelial ovarian cancer is the leading cause of death among gynaecological cancers. Previous studies have demonstrated that epidermal growth factor receptor (EGFR) ligands can induce ovarian cancer cell invasion by down-regulating E-cadherin. Betacellulin is a unique member of the EGF family. It is overexpressed in a variety of cancers and is associated with reduced survival. However, the biological functions and clinical significance of betacellulin in ovarian cancer remain unknown. In the current study, we tested the hypothesis that betacellulin induces ovarian cancer cell migration by suppressing E-cadherin expression. Treatment of SKOV3 and OVCAR5 ovarian cancer cell lines with betacellulin down-regulated E-cadherin, but not N-cadherin. In addition, betacellulin treatment increased the expression of Snail and Slug, and these effects were completely blocked by pre-treatment with EGFR inhibitor AG1478. Interestingly, only knockdown of Slug reversed the down-regulation of E-cadherin by betacellulin. Betacellulin treatment induced the activation of both the MEK-ERK and PI3K-Akt signaling pathways, and it also significantly increased ovarian cancer cell migration. Importantly, the effects of betacellulin on E-cadherin, Slug and cell migration were attenuated by pre-treatment with either U0126 or LY294002. Our results suggest that betacellulin induces ovarian cancer migration and Slug-dependent E-cadherin down-regulation via EGFR-mediated MEK-ERK and PI3K-Akt signaling. PMID:27129169

The E3 ligase UBR5 regulates gastric cancer cell growth by destabilizing the tumor suppressor GKN1

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

Yang, Min; Jiang, Nan; Cao, Qi-wei

Gastric cancer is the most common digestive malignant tumor worldwide and the underlying mechanisms are not fully understood. The E3 ligase UBR5 (also known as EDD1) is essentially involved in diverse types of cancer. Here we aimed to study the functions of UBR5 in human gastric cancer. We first analyzed the mRNA and protein levels of UBR5 in human gastric cancer tissues and the results showed that UBR5 was markedly increased in gastric cancer tissues compared with normal gastric mucosa or matched non-cancer gastric tissues. The relationship between UBR5 and survival of gastric cancer patients was analyzed and we foundmore » that high UBR5 expression was associated with poor overall and disease-free survival. We further tried to investigate the effects of UBR5 on gastric cancer cell growth in vitro and in vivo. Therefore, we knocked down UBR5 with lentivirus-mediated shRNA and found that UBR5 knockdown repressed in vitro proliferation and colony formation of gastric cancer cells AGS, MG803 and MNK1. In vivo xenograft experiment also demonstrated that UBR5 knockdown inhibited AGS growth. Finally, we explored the mechanism by which UBR5 contributed to the growth of gastric cancer cells. We found that UBR5 bound the tumor suppressor gastrokine 1 (GKN1) and increased its ubiquitination to reduce the protein stability of GKN1. GKN1 knockdown with lentivirus-mediated shRNA increased the in vitro colony formation and in vivo growth of AGS cells, and UBR5 knockdown was unable to affect the colony formation and in vivo growth of AGS cells when GKN1 was knocked down, indicating that GKN1 contributed to the effects of UBR5 in human gastric cancer cells. Taken together, UBR5 plays an essential role in gastric cancer and may be a potential diagnosis and treatment target for gastric cancer. - Highlights: • UBR5 expression is up-regulated in human gastric cancer. • UBR5 overexpression predicts poor survival. • UBR5 regulates gastric cancer growth in vitro and in vivo. • UBR5 reduces the protein stability of GKN1.« less

Prion-like domains in RNA binding proteins are essential for building subnuclear paraspeckles

PubMed Central

Hennig, Sven; Kong, Geraldine; Mannen, Taro; Sadowska, Agata; Kobelke, Simon; Blythe, Amanda; Knott, Gavin J.; Iyer, K. Swaminathan; Ho, Diwei; Newcombe, Estella A.; Hosoki, Kana; Goshima, Naoki; Kawaguchi, Tetsuya; Hatters, Danny; Trinkle-Mulcahy, Laura; Hirose, Tetsuro; Bond, Charles S.

2015-01-01

Prion-like domains (PLDs) are low complexity sequences found in RNA binding proteins associated with the neurodegenerative disorder amyotrophic lateral sclerosis. Recently, PLDs have been implicated in mediating gene regulation via liquid-phase transitions that drive ribonucleoprotein granule assembly. In this paper, we report many PLDs in proteins associated with paraspeckles, subnuclear bodies that form around long noncoding RNA. We mapped the interactome network of paraspeckle proteins, finding enrichment of PLDs. We show that one protein, RBM14, connects key paraspeckle subcomplexes via interactions mediated by its PLD. We further show that the RBM14 PLD, as well as the PLD of another essential paraspeckle protein, FUS, is required to rescue paraspeckle formation in cells in which their endogenous counterpart has been knocked down. Similar to FUS, the RBM14 PLD also forms hydrogels with amyloid-like properties. These results suggest a role for PLD-mediated liquid-phase transitions in paraspeckle formation, highlighting this nuclear body as an excellent model system for understanding the perturbation of such processes in neurodegeneration. PMID:26283796

gp96 expression in neutrophils is critical for the onset of Escherichia coli K1 (RS218) meningitis

PubMed Central

Mittal, Rahul; Prasadarao, Nemani V.

2012-01-01

Despite the fundamental function of neutrophils (PMNs) in innate immunity, their role in Escherichia coli K1 (EC-K1) induced meningitis is unexplored. Here we show that PMN-depleted mice are resistant to EC-K1 (RS218) meningitis. EC-K1 survives and multiplies in PMNs for which outer membrane protein A (OmpA) expression is essential. EC-K1infection of PMNs increases the cell surface expression of gp96, which acts as a receptor for bacterial entry. Suppression of gp96 expression in newborn mice prevents the onset of EC-K1 meningitis. Infection of PMNs with EC-K1 suppresses oxidative burst by down regulating rac1, rac2 and gp91phox transcription both in vitro and in vivo. The interaction of loop 2 of OmpA with gp96 is essential for EC-K1-mediated inhibition of oxidative burst. These results reveal that EC-K1 exploits surface expressed gp96 in PMNs to prevent oxidative burst for the onset of neonatal meningitis. PMID:22109526

Rho-associated kinase (ROCK) function is essential for cell cycle progression, senescence and tumorigenesis

PubMed Central

Kümper, Sandra; Mardakheh, Faraz K; McCarthy, Afshan; Yeo, Maggie; Stamp, Gordon W; Paul, Angela; Worboys, Jonathan; Sadok, Amine; Jørgensen, Claus; Guichard, Sabrina

2016-01-01

Rho-associated kinases 1 and 2 (ROCK1/2) are Rho-GTPase effectors that control key aspects of the actin cytoskeleton, but their role in proliferation and cancer initiation or progression is not known. Here, we provide evidence that ROCK1 and ROCK2 act redundantly to maintain actomyosin contractility and cell proliferation and that their loss leads to cell-cycle arrest and cellular senescence. This phenotype arises from down-regulation of the essential cell-cycle proteins CyclinA, CKS1 and CDK1. Accordingly, while the loss of either Rock1 or Rock2 had no negative impact on tumorigenesis in mouse models of non-small cell lung cancer and melanoma, loss of both blocked tumor formation, as no tumors arise in which both Rock1 and Rock2 have been genetically deleted. Our results reveal an indispensable role for ROCK, yet redundant role for isoforms 1 and 2, in cell cycle progression and tumorigenesis, possibly through the maintenance of cellular contractility. DOI: http://dx.doi.org/10.7554/eLife.12203.001 PMID:26765561

Endothelial Depletion of Acvrl1 in Mice Leads to Arteriovenous Malformations Associated with Reduced Endoglin Expression

PubMed Central

Allinson, Kathleen R.; Redgrave, Rachael E.; Zhai, Zhenhua; Oh, S. Paul; Fruttiger, Marcus; Arthur, Helen M.

2014-01-01

Rare inherited cardiovascular diseases are frequently caused by mutations in genes that are essential for the formation and/or function of the cardiovasculature. Hereditary Haemorrhagic Telangiectasia is a familial disease of this type. The majority of patients carry mutations in either Endoglin (ENG) or ACVRL1 (also known as ALK1) genes, and the disease is characterized by arteriovenous malformations and persistent haemorrhage. ENG and ACVRL1 encode receptors for the TGFβ superfamily of ligands, that are essential for angiogenesis in early development but their roles are not fully understood. Our goal was to examine the role of Acvrl1 in vascular endothelial cells during vascular development and to determine whether loss of endothelial Acvrl1 leads to arteriovenous malformations. Acvrl1 was depleted in endothelial cells either in early postnatal life or in adult mice. Using the neonatal retinal plexus to examine angiogenesis, we observed that loss of endothelial Acvrl1 led to venous enlargement, vascular hyperbranching and arteriovenous malformations. These phenotypes were associated with loss of arterial Jag1 expression, decreased pSmad1/5/8 activity and increased endothelial cell proliferation. We found that Endoglin was markedly down-regulated in Acvrl1-depleted ECs showing endoglin expression to be downstream of Acvrl1 signalling in vivo. Endothelial-specific depletion of Acvrl1 in pups also led to pulmonary haemorrhage, but in adult mice resulted in caecal haemorrhage and fatal anaemia. We conclude that during development, endothelial Acvrl1 plays an essential role to regulate endothelial cell proliferation and arterial identity during angiogenesis, whilst in adult life endothelial Acvrl1 is required to maintain vascular integrity. PMID:24896812

Identification of the key regulating genes of diminished ovarian reserve (DOR) by network and gene ontology analysis.

PubMed

Pashaiasl, Maryam; Ebrahimi, Mansour; Ebrahimie, Esmaeil

2016-09-01

Diminished ovarian reserve (DOR) is one of the reasons for infertility that not only affects both older and young women. Ovarian reserve assessment can be used as a new prognostic tool for infertility treatment decision making. Here, up- and down-regulated gene expression profiles of granulosa cells were analysed to generate a putative interaction map of the involved genes. In addition, gene ontology (GO) analysis was used to get insight intol the biological processes and molecular functions of involved proteins in DOR. Eleven up-regulated genes and nine down-regulated genes were identified and assessed by constructing interaction networks based on their biological processes. PTGS2, CTGF, LHCGR, CITED, SOCS2, STAR and FSTL3 were the key nodes in the up-regulated networks, while the IGF2, AMH, GREM, and FOXC1 proteins were key in the down-regulated networks. MIRN101-1, MIRN153-1 and MIRN194-1 inhibited the expression of SOCS2, while CSH1 and BMP2 positively regulated IGF1 and IGF2. Ossification, ovarian follicle development, vasculogenesis, sequence-specific DNA binding transcription factor activity, and golgi apparatus are the major differential groups between up-regulated and down-regulated genes in DOR. Meta-analysis of publicly available transcriptomic data highlighted the high coexpression of CTGF, connective tissue growth factor, with the other key regulators of DOR. CTGF is involved in organ senescence and focal adhesion pathway according to GO analysis. These findings provide a comprehensive system biology based insight into the aetiology of DOR through network and gene ontology analyses.

Transcriptomic Analysis of Grapevine (cv. Summer Black) Leaf, Using the Illumina Platform

PubMed Central

Pervaiz, Tariq; Haifeng, Jia; Salman Haider, Muhammad; Cheng, Zhang; Cui, Mengjie; Wang, Mengqi; Cui, Liwen; Wang, Xicheng; Fang, Jinggui

2016-01-01

Proceeding to illumina sequencing, determining RNA integrity numbers for poly RNA were separated from each of the four developmental stages of cv. Summer Black leaves by using Illumina HiSeq™ 2000. The sums of 272,941,656 reads were generated from vitis vinifera leaf at four different developmental stages, with more than 27 billion nucleotides of the sequence data. At each growth stage, RNA samples were indexed through unique nucleic acid identifiers and sequenced. KEGG annotation results depicted that the highest number of transcripts in 2,963 (2Avs4A) followed by 1Avs4A (2,920), and 3Avs4A (2,294) out of 15,614 (71%) transcripts were recorded. In comparison, a total of 1,532 transcripts were annotated in GOs, including Cellular component, with the highest number in “Cell part” 251 out of 353 transcripts (71.1%), followed by intracellular organelle 163 out of 353 transcripts (46.2%), while in molecular function and metabolic process 375 out of 525 (71.4%) transcripts, multicellular organism process 40 out of 525 (7.6%) transcripts in biological process were most common in 1Avs2A. While in case of 1Avs3A, cell part 476 out of 662 transcripts (71.9%), and membrane-bounded organelle 263 out of 662 transcripts (39.7%) were recorded in Cellular component. In the grapevine transcriptome, during the initial stages of leaf development 1Avs2A showed single transcript was down-regulated and none of them were up-regulated. While in comparison of 1A to 3A showed one up-regulated (photosystem II reaction center protein C) and one down regulated (conserved gene of unknown function) transcripts, during the hormone regulating pathway namely SAUR-like auxin-responsive protein family having 2 up-regulated and 7 down-regulated transcripts, phytochrome-associated protein showed 1 up-regulated and 9 down-regulated transcripts, whereas genes associated with the Leucine-rich repeat protein kinase family protein showed 7 up-regulated and 1 down-regulated transcript, meanwhile Auxin Resistant 2 has single up-regulated transcript in second developmental stage, although 3 were down-regulated at lateral growth stages (3A and 4A). In the present study, 489 secondary metabolic pathways related genes were identified during leaf growth, which mainly includes alkaloid (40), anthocyanins (21), Diterpenoid (144), Monoterpenoid (90) and Flavonoids (93). Quantitative real-time PCR was applied to validate 10 differentially expressed transcripts patterns from flower, leaf and fruit metabolic pathways at different growth stages. PMID:26824474

ADAR1 regulates ARHGAP26 gene expression through RNA editing by disrupting miR-30b-3p and miR-573 binding.

PubMed

Wang, Qiong; Hui, Haipeng; Guo, Zhendong; Zhang, Weina; Hu, Yaou; He, Tao; Tai, Yanhong; Peng, Peng; Wang, Li

2013-11-01

Rho GTPase activating protein 26 (ARHGAP26) is a negative regulator of the Rho family that converts the small G proteins RhoA and Cdc42 to their inactive GDP-bound forms. It is essential for the CLIC/GEEC endocytic pathway, cell spreading, and muscle development. The present study shows that ARHGAP26 mRNA undergoes extensive A-to-I RNA editing in the 3' UTR that is specifically catalyzed by ADAR1. Furthermore, the mRNA and protein levels of ARHGAP26 were decreased in cells in which ADAR1 was knocked down. Conversely, ADAR1 overexpression increased the abundance of ARHGAP26 mRNA and protein. In addition, we found that both miR-30b-3p and miR-573 target the ARHGAP26 gene and that RNA editing of ARHGAP26 mediated by ADAR1 abolished the repression of its expression by miR-30b-3p or miR-573. When ADAR1 was overexpressed, the reduced abundance of ARHGAP26 protein mediated by miR-30b-3p or miR-573 was rescued. Importantly, we also found that knocking down ADAR1 elevated RhoA activity, which was consistent with the reduced level of ARHGAP26. Conversely, when ADAR1 was overexpressed, the amount of RhoA-GTP decreased. The similar expression patterns of ARHGAP26 and ADAR1 in human tissue samples further confirmed our findings. Taken together, our results suggest that ADAR1 regulates the expression of ARHGAP26 through A-to-I RNA editing by disrupting the binding of miR-30b-3p and miR-573 within the 3' UTR of ARHGAP26. This study provides a novel insight into the mechanism by which ADAR1 and its RNA editing function regulate microRNA-mediated modulation of target genes.

Crystal structure of the Src family kinase Hck SH3-SH2 linker regulatory region supports an SH3-dominant activation mechanism.

PubMed

Alvarado, John J; Betts, Laurie; Moroco, Jamie A; Smithgall, Thomas E; Yeh, Joanne I

2010-11-12

Most mammalian cell types depend on multiple Src family kinases (SFKs) to regulate diverse signaling pathways. Strict control of SFK activity is essential for normal cellular function, and loss of kinase regulation contributes to several forms of cancer and other diseases. Previous x-ray crystal structures of the SFKs c-Src and Hck revealed that intramolecular association of their Src homology (SH) 3 domains and SH2 kinase linker regions has a key role in down-regulation of kinase activity. However, the amino acid sequence of the Hck linker represents a suboptimal ligand for the isolated SH3 domain, suggesting that it may form the polyproline type II helical conformation required for SH3 docking only in the context of the intact structure. To test this hypothesis directly, we determined the crystal structure of a truncated Hck protein consisting of the SH2 and SH3 domains plus the linker. Despite the absence of the kinase domain, the structures and relative orientations of the SH2 and SH3 domains in this shorter protein were very similar to those observed in near full-length, down-regulated Hck. However, the SH2 kinase linker adopted a modified topology and failed to engage the SH3 domain. This new structure supports the idea that these noncatalytic regions work together as a "conformational switch" that modulates kinase activity in a manner unique to the SH3 domain and linker topologies present in the intact Hck protein. Our results also provide fresh structural insight into the facile induction of Hck activity by HIV-1 Nef and other Hck SH3 domain binding proteins and implicate the existence of innate conformational states unique to individual Src family members that "fine-tune" their sensitivities to activation by SH3-based ligands.

Variation on Composition and Bioactivity of Essential Oils of Four Common Curcuma Herbs.

PubMed

Zhang, Lanyue; Yang, Zhiwen; Chen, Dingkang; Huang, Zebin; Li, Yongliang; Lan, Xinzi; Su, Ping; Pan, Wanyi; Zhou, Wei; Zheng, Xi; Du, Zhiyun

2017-11-01

Chemical compositions, antioxidative, antimicrobial, anti-inflammatory, and cytotoxic activities of essential oils extracted from four common Curcuma species (Curcuma longa, Curcuma phaeocaulis, Curcuma wenyujin, and Curcuma kwangsiensis) rhizomes in P. R. China are comparatively studied. In total, 47, 49, 35, and 30 compounds are identified in C. longa, C. phaeocaulis, C. wenyujin, and C. kwangsiensis essential oils by GC/MS, and their richest compounds are ar-turmerone (21.67%), elemenone (19.41%), curdione (40.23%) and (36.47%), respectively. Moreover, C. kwangsiensis essential oils display the strongest DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging activity (IC 50 , 3.47 μg/ml), much higher than ascorbic acid (6.50 μg/ml). C. phaeocaulis oils show the best antibacterial activities against Escherichia coli (MIC, 235.54 μg/ml), Pseudomonas aeruginosa (391.31 μg/ml) and Staphylococcus aureus (378.36 μg/ml), while C. wenyujin and C. kwangsiensis oils show optimum activities against Candida albicans (208.61 μg/ml) and Saccharomyces cerevisiae (193.27 μg/ml), respectively. C. phaeocaulis (IC 50 , 4.63 μg/ml) and C. longa essential oils (73.05 μg/ml) have the best cytotoxicity against LNCaP and HepG2, respectively. C. kwangsiensis oils also exhibit the strongest anti-inflammatory activities by remarkably down-regulating expression of COX-2 and TNF-α. Therefore, due to their different chemical compositions and bioactivities, traditional Chinese Curcuma herbs should be differentially served as natural additives for food, pharmaceutical, and cosmetic. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

Down-regulation of Wild-type p53-induced Phosphatase 1 (Wip1) Plays a Critical Role in Regulating Several p53-dependent Functions in Premature Senescent Tumor Cells*

PubMed Central

Crescenzi, Elvira; Raia, Zelinda; Pacifico, Francesco; Mellone, Stefano; Moscato, Fortunato; Palumbo, Giuseppe; Leonardi, Antonio

2013-01-01

Premature or drug-induced senescence is a major cellular response to chemotherapy in solid tumors. The senescent phenotype develops slowly and is associated with chronic DNA damage response. We found that expression of wild-type p53-induced phosphatase 1 (Wip1) is markedly down-regulated during persistent DNA damage and after drug release during the acquisition of the senescent phenotype in carcinoma cells. We demonstrate that down-regulation of Wip1 is required for maintenance of permanent G2 arrest. In fact, we show that forced expression of Wip1 in premature senescent tumor cells induces inappropriate re-initiation of mitosis, uncontrolled polyploid progression, and cell death by mitotic failure. Most of the effects of Wip1 may be attributed to its ability to dephosphorylate p53 at Ser15 and to inhibit DNA damage response. However, we also uncover a regulatory pathway whereby suppression of p53 Ser15 phosphorylation is associated with enhanced phosphorylation at Ser46, increased p53 protein levels, and induction of Noxa expression. On the whole, our data indicate that down-regulation of Wip1 expression during premature senescence plays a pivotal role in regulating several p53-dependent aspects of the senescent phenotype. PMID:23612976

Environmental projects. Volume 2: Underground storage tanks compliance program

NASA Technical Reports Server (NTRS)

Kushner, L.

1987-01-01

Six large parabolic dish antennas are located at the Goldstone Deep Space Communications Complex north of Barstow, California. As a large-scale facility located in a remote, isolated desert region, the GDSCC operations require numerous on-site storage facilities for gasoline, diesel and hydraulic oil. These essential fluids are stored in underground storage tanks (USTs). Because USTs may develop leaks with the resultant seepage of their hazardous contents into the surrounding soil, local, State and Federal authorities have adopted stringent regulations for the testing and maintenance of USTs. Under the supervision of JPL's Office of Telecommunications and Data Acquisition, a year-long program has brought 27 USTs at the Goldstone Complex into compliance with Federal, State of California and County of San Bernadino regulations. Of these 27 USTs, 15 are operating today, 11 have been temporary closed down, and 1 abandoned in place. In 1989, the 15 USTs now operating at the Goldstone DSCC will be replaced either by modern, double-walled USTs equipped with automatic sensors for leak detection, or by above ground storage tanks. The 11 inactivated USTs are to be excavated, removed and disposed of according to regulation.

Gene Silencing of Argonaute5 Negatively Affects the Establishment of the Legume-Rhizobia Symbiosis

PubMed Central

Reyero-Saavedra, María del Rocio; Qiao, Zhenzhen; Sánchez-Correa, María del Socorro; Díaz-Pineda, M. Enrique; Covarrubias, Alejandra A.; Libault, Marc; Valdés-López, Oswaldo

2017-01-01

The establishment of the symbiosis between legumes and nitrogen-fixing rhizobia is finely regulated at the transcriptional, posttranscriptional and posttranslational levels. Argonaute5 (AGO5), a protein involved in RNA silencing, can bind both viral RNAs and microRNAs to control plant-microbe interactions and plant physiology. For instance, AGO5 regulates the systemic resistance of Arabidopsis against Potato Virus X as well as the pigmentation of soybean (Glycine max) seeds. Here, we show that AGO5 is also playing a central role in legume nodulation based on its preferential expression in common bean (Phaseolus vulgaris) and soybean roots and nodules. We also report that the expression of AGO5 is induced after 1 h of inoculation with rhizobia. Down-regulation of AGO5 gene in P. vulgaris and G. max causes diminished root hair curling, reduces nodule formation and interferes with the induction of three critical symbiotic genes: Nuclear Factor Y-B (NF-YB), Nodule Inception (NIN) and Flotillin2 (FLOT2). Our findings provide evidence that the common bean and soybean AGO5 genes play an essential role in the establishment of the symbiosis with rhizobia. PMID:29182547

Who Deserves Help? Evolutionary Psychology, Social Emotions, and Public Opinion about Welfare

PubMed Central

Petersen, Michael Bang; Sznycer, Daniel; Cosmides, Leda; Tooby, John

2013-01-01

Evidence suggests that our foraging ancestors engaged in the small-scale equivalent of social insurance as an essential tool of survival and evolved a sophisticated psychology of social exchange (involving the social emotions of compassion and anger) to regulate mutual assistance. Here, we hypothesize that political support for modern welfare policies are shaped by these evolved mental programs. In particular, the compassionate motivation to share with needy nonfamily could not have evolved without defenses against opportunists inclined to take without contributing. Cognitively, such parasitic strategies can be identified by the intentional avoidance of productive effort. When detected, this pattern should trigger anger and down-regulate support for assistance. We tested predictions derived from these hypotheses in four studies in two cultures, showing that subjects’ perceptions of recipients’ effort to find work drive welfare opinions; that such perceptions (and not related perceptions) regulate compassion and anger (and not related emotions); that the effects of perceptions of recipients’ effort on opinions about welfare are mediated by anger and compassion, independently of political ideology; and that these emotions not only influence the content of welfare opinions but also how easily they are formed. PMID:23355755

LIN9, a Subunit of the DREAM Complex, Regulates Mitotic Gene Expression and Proliferation of Embryonic Stem Cells

PubMed Central

Esterlechner, Jasmina; Reichert, Nina; Iltzsche, Fabian; Krause, Michael; Finkernagel, Florian; Gaubatz, Stefan

2013-01-01

The DREAM complex plays an important role in regulation of gene expression during the cell cycle. We have previously shown that the DREAM subunit LIN9 is required for early embryonic development and for the maintenance of the inner cell mass in vitro. In this study we examined the effect of knocking down LIN9 on ESCs. We demonstrate that depletion of LIN9 alters the cell cycle distribution of ESCs and results in an accumulation of cells in G2 and M and in an increase of polyploid cells. Genome-wide expression studies showed that the depletion of LIN9 results in downregulation of mitotic genes and in upregulation of differentiation-specific genes. ChIP-on chip experiments showed that mitotic genes are direct targets of LIN9 while lineage specific markers are regulated indirectly. Importantly, depletion of LIN9 does not alter the expression of pluripotency markers SOX2, OCT4 and Nanog and LIN9 depleted ESCs retain alkaline phosphatase activity. We conclude that LIN9 is essential for proliferation and genome stability of ESCs by activating genes with important functions in mitosis and cytokinesis. PMID:23667535

Gene Silencing of Argonaute5 Negatively Affects the Establishment of the Legume-Rhizobia Symbiosis.

PubMed

Reyero-Saavedra, María Del Rocio; Qiao, Zhenzhen; Sánchez-Correa, María Del Socorro; Díaz-Pineda, M Enrique; Reyes, Jose L; Covarrubias, Alejandra A; Libault, Marc; Valdés-López, Oswaldo

2017-11-28

The establishment of the symbiosis between legumes and nitrogen-fixing rhizobia is finely regulated at the transcriptional, posttranscriptional and posttranslational levels. Argonaute5 (AGO5), a protein involved in RNA silencing, can bind both viral RNAs and microRNAs to control plant-microbe interactions and plant physiology. For instance, AGO5 regulates the systemic resistance of Arabidopsis against Potato Virus X as well as the pigmentation of soybean ( Glycine max ) seeds. Here, we show that AGO5 is also playing a central role in legume nodulation based on its preferential expression in common bean ( Phaseolus vulgaris ) and soybean roots and nodules. We also report that the expression of AGO5 is induced after 1 h of inoculation with rhizobia. Down-regulation of AGO5 gene in P. vulgaris and G. max causes diminished root hair curling, reduces nodule formation and interferes with the induction of three critical symbiotic genes: Nuclear Factor Y-B ( NF-YB ), Nodule Inception ( NIN ) and Flotillin2 ( FLOT2 ). Our findings provide evidence that the common bean and soybean AGO5 genes play an essential role in the establishment of the symbiosis with rhizobia.

A novel role for drebrin in regulating progranulin bioactivity in bladder cancer.

PubMed

Xu, Shi-Qiong; Buraschi, Simone; Morcavallo, Alaide; Genua, Marco; Shirao, Tomoaki; Peiper, Stephen C; Gomella, Leonard G; Birbe, Ruth; Belfiore, Antonino; Iozzo, Renato V; Morrione, Andrea

2015-05-10

We recently established a critical role for the growth factor progranulin in bladder cancer insofar as progranulin promotes urothelial cancer cell motility and contributes, as an autocrine growth factor, to the transformed phenotype by modulating invasion and anchorage-independent growth. In addition, progranulin expression is upregulated in invasive bladder cancer tissues compared to normal controls. However, the molecular mechanisms of progranulin action in bladder cancer have not been fully elucidated. In this study, we searched for novel progranulin-interacting proteins using pull-down assays with recombinant progranulin and proteomics. We discovered that drebrin, an F-actin binding protein, bound progranulin in urothelial cancer cells. We characterized drebrin function in urothelial cancer cell lines and showed that drebrin is critical for progranulin-dependent activation of the Akt and MAPK pathways and modulates motility, invasion and anchorage-independent growth. In addition, drebrin regulates tumor formation in vivo and its expression is upregulated in bladder cancer tissues compared to normal tissue controls. Our data are translationally relevant as indicate that drebrin exerts an essential functional role in the regulation of progranulin action and may constitute a novel target for therapeutic intervention in bladder tumors. In addition, drebrin may serve as novel biomarker for bladder cancer.

Adaptor protein Lnk negatively regulates the mutant MPL, MPLW515L associated with myeloproliferative disorders

PubMed Central

Gueller, Saskia; Chumakova, Katya; Kawamata, Norihiko; Liu, Liqin; Koeffler, H. Phillip

2007-01-01

Recently, activating myeloproliferative leukemia virus oncogene (MPL) mutations, MPLW515L/K, were described in myeloproliferative disorder (MPD) patients. MPLW515L leads to activation of downstream signaling pathways and cytokine-independent proliferation in hematopoietic cells. The adaptor protein Lnk is a negative regulator of several cytokine receptors, including MPL. We show that overexpression of Lnk in Ba/F3-MPLW515L cells inhibits cytokine-independent growth, while suppression of Lnk in UT7-MPLW515L cells enhances proliferation. Lnk blocks the activation of Jak2, Stat3, Erk, and Akt in these cells. Furthermore, MPLW515L-expressing cells are more susceptible to Lnk inhibitory functions than their MPL wild-type (MPLWT)–expressing counterparts. Lnk associates with activated MPLWT and MPLW515L and colocalizes with the receptors at the plasma membrane. The SH2 domain of Lnk is essential for its binding and for its down-regulation of MPLWT and MPLW515L. Lnk itself is tyrosine-phosphorylated following thrombopoietin stimulation. Further elucidating the cellular pathways that attenuate MPLW515L will provide insight into the pathogenesis of MPD and could help develop specific therapeutic approaches. PMID:17693582

Adaptor protein Lnk negatively regulates the mutant MPL, MPLW515L associated with myeloproliferative disorders.

PubMed

Gery, Sigal; Gueller, Saskia; Chumakova, Katya; Kawamata, Norihiko; Liu, Liqin; Koeffler, H Phillip

2007-11-01

Recently, activating myeloproliferative leukemia virus oncogene (MPL) mutations, MPLW515L/K, were described in myeloproliferative disorder (MPD) patients. MPLW515L leads to activation of downstream signaling pathways and cytokine-independent proliferation in hematopoietic cells. The adaptor protein Lnk is a negative regulator of several cytokine receptors, including MPL. We show that overexpression of Lnk in Ba/F3-MPLW515L cells inhibits cytokine-independent growth, while suppression of Lnk in UT7-MPLW515L cells enhances proliferation. Lnk blocks the activation of Jak2, Stat3, Erk, and Akt in these cells. Furthermore, MPLW515L-expressing cells are more susceptible to Lnk inhibitory functions than their MPL wild-type (MPLWT)-expressing counterparts. Lnk associates with activated MPLWT and MPLW515L and colocalizes with the receptors at the plasma membrane. The SH2 domain of Lnk is essential for its binding and for its down-regulation of MPLWT and MPLW515L. Lnk itself is tyrosine-phosphorylated following thrombopoietin stimulation. Further elucidating the cellular pathways that attenuate MPLW515L will provide insight into the pathogenesis of MPD and could help develop specific therapeutic approaches.

Molecular adaptations to phosphorus deprivation and comparison with nitrogen deprivation responses in the diatom Phaeodactylum tricornutum.

PubMed

Alipanah, Leila; Winge, Per; Rohloff, Jens; Najafi, Javad; Brembu, Tore; Bones, Atle M

2018-01-01

Phosphorus, an essential element for all living organisms, is a limiting nutrient in many regions of the ocean due to its fast recycling. Changes in phosphate (Pi) availability in aquatic systems affect diatom growth and productivity. We investigated the early adaptive mechanisms in the marine diatom Phaeodactylum tricornutum to P deprivation using a combination of transcriptomics, metabolomics, physiological and biochemical experiments. Our analysis revealed strong induction of gene expression for proteins involved in phosphate acquisition and scavenging, and down-regulation of processes such as photosynthesis, nitrogen assimilation and nucleic acid and ribosome biosynthesis. P deprivation resulted in alterations of carbon allocation through the induction of the pentose phosphate pathway and cytosolic gluconeogenesis, along with repression of the Calvin cycle. Reorganization of cellular lipids was indicated by coordinated induced expression of phospholipases, sulfolipid biosynthesis enzymes and a putative betaine lipid biosynthesis enzyme. A comparative analysis of nitrogen- and phosphorus-deprived P. tricornutum revealed both common and distinct regulation patterns in response to phosphate and nitrate stress. Regulation of central carbon metabolism and amino acid metabolism was similar, whereas unique responses were found in nitrogen assimilation and phosphorus scavenging in nitrogen-deprived and phosphorus-deprived cells, respectively.

The cardiac copper chaperone proteins Sco1 and CCS are up-regulated, but Cox 1 and Cox4 are down-regulated, by copper deficiency.

PubMed

Getz, Jean; Lin, Dingbo; Medeiros, Denis M

2011-10-01

Copper is ferried in a cell complexed to chaperone proteins, and in the heart much copper is required for cytochrome c oxidase (Cox). It is not completely understood how copper status affects the levels of these proteins. Here we determined if dietary copper deficiency could up- or down-regulate select copper chaperone proteins and Cox subunits 1 and 4 in cardiac tissue of rats. Sixteen weanling male Long-Evans rats were randomized into treatment groups, one group receiving a copper-deficient diet (<1 mg Cu/kg diet) and one group receiving a diet containing adequate copper (6 mg Cu/kg diet) for 5 weeks. Hearts were removed, weighed, and non-myofibrillar proteins separated to analyze for levels of CCS, Sco1, Ctr1, Cox17, Cox1, and Cox4 by SDS-PAGE and Western blotting. No changes were observed in the concentrations of CTR1 and Cox17 between copper-adequate and copper-deficient rats. CCS and Sco1 were up-regulated and Cox1 and Cox4 were both down-regulated as a result of copper deficiency. These data suggest that select chaperone proteins and may be up-regulated, and Cox1 and 4 down-regulated, by a dietary copper deficiency, whereas others appear not to be affected by copper status.

Micro-RNA-128 (miRNA-128) down-regulation in glioblastoma targets ARP5 (ANGPTL6), Bmi-1 and E2F-3a, key regulators of brain cell proliferation.

PubMed

Cui, J G; Zhao, Y; Sethi, P; Li, Y Y; Mahta, A; Culicchia, F; Lukiw, W J

2010-07-01

High density micro-RNA (miRNA) arrays, fluorescent-reporter miRNA assay and Northern miRNA dot-blot analysis show that a brain-enriched miRNA-128 is significantly down-regulated in glioblastoma multiforme (GBM) and in GBM cell lines when compared to age-matched controls. The down-regulation of miRNA-128 was found to inversely correlate with WHO tumor grade. Three bioinformatics-verified miRNA-128 targets, angiopoietin-related growth factor protein 5 (ARP5; ANGPTL6), a transcription suppressor that promotes stem cell renewal and inhibits the expression of known tumor suppressor genes involved in senescence and differentiation, Bmi-1, and a transcription factor critical for the control of cell-cycle progression, E2F-3a, were found to be up-regulated. Addition of exogenous miRNA-128 to CRL-1690 and CRL-2610 GBM cell lines (a) restored 'homeostatic' ARP5 (ANGPTL6), Bmi-1 and E2F-3a expression, and (b) significantly decreased the proliferation of CRL-1690 and CRL-2610 cell lines. Our data suggests that down-regulation of miRNA-128 may contribute to glioma and GBM, in part, by coordinately up-regulating ARP5 (ANGPTL6), Bmi-1 and E2F-3a, resulting in the proliferation of undifferentiated GBM cells.

Neurofeedback of visual food cue reactivity: a potential avenue to alter incentive sensitization and craving.

PubMed

Ihssen, Niklas; Sokunbi, Moses O; Lawrence, Andrew D; Lawrence, Natalia S; Linden, David E J

2017-06-01

FMRI-based neurofeedback transforms functional brain activation in real-time into sensory stimuli that participants can use to self-regulate brain responses, which can aid the modification of mental states and behavior. Emerging evidence supports the clinical utility of neurofeedback-guided up-regulation of hypoactive networks. In contrast, down-regulation of hyperactive neural circuits appears more difficult to achieve. There are conditions though, in which down-regulation would be clinically useful, including dysfunctional motivational states elicited by salient reward cues, such as food or drug craving. In this proof-of-concept study, 10 healthy females (mean age = 21.40 years, mean BMI = 23.53) who had fasted for 4 h underwent a novel 'motivational neurofeedback' training in which they learned to down-regulate brain activation during exposure to appetitive food pictures. FMRI feedback was given from individually determined target areas and through decreases/increases in food picture size, thus providing salient motivational consequences in terms of cue approach/avoidance. Our preliminary findings suggest that motivational neurofeedback is associated with functionally specific activation decreases in diverse cortical/subcortical regions, including key motivational areas. There was also preliminary evidence for a reduction of hunger after neurofeedback and an association between down-regulation success and the degree of hunger reduction. Decreasing neural cue responses by motivational neurofeedback may provide a useful extension of existing behavioral methods that aim to modulate cue reactivity. Our pilot findings indicate that reduction of neural cue reactivity is not achieved by top-down regulation but arises in a bottom-up manner, possibly through implicit operant shaping of target area activity.

Toxins, Butyric Acid, and Other Short-Chain Fatty Acids Are Coordinately Expressed and Down-Regulated by Cysteine in Clostridium difficile

PubMed Central

Karlsson, Sture; Lindberg, Anette; Norin, Elisabeth; Burman, Lars G.; Åkerlund, Thomas

2000-01-01

It was recently found that a mixture of nine amino acids down-regulate Clostridium difficile toxin production when added to peptone yeast extract (PY) cultures of strain VPI 10463 (S. Karlsson, L. G. Burman, and T. Åkerlund, Microbiology 145:1683–1693, 1999). In the present study, seven of these amino acids were found to exhibit a moderate suppression of toxin production, whereas proline and particularly cysteine had the greatest impact, on both reference strains (n = 6) and clinical isolates (n = 28) of C. difficile (>99% suppression by cysteine in the highest toxin-producing strain). Also, cysteine derivatives such as acetylcysteine, glutathione, and cystine effectively down-regulated toxin expression. An impact of both cysteine and cystine but not of thioglycolate on toxin yield indicated that toxin expression was not regulated by the oxidation-reduction potential. Several metabolic pathways, including butyric acid and butanol production, were coinduced with the toxins in PY and down-regulated by cysteine. The enzyme 3-hydroxybutyryl coenzyme A dehydrogenase, a key enzyme in solventogenesis in Clostridium acetobutylicum, was among the most up-regulated proteins during high toxin production. The addition of butyric acid to various growth media induced toxin production, whereas the addition of butanol had the opposite effect. The results indicate a coupling between specific metabolic processes and toxin expression in C. difficile and that certain amino acids can alter these pathways coordinately. We speculate that down-regulation of toxin production by the administration of such amino acids to the colon may become a novel approach to prophylaxis and therapy for C. difficile-associated diarrhea. PMID:10992498

Nurr1 overexpression exerts neuroprotective and anti-inflammatory roles via down-regulating CCL2 expression in both in vivo and in vitro Parkinson's disease models

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

Liu, Wei; Gao, Yang; Chang, Na

The abnormality of nuclear receptor-related protein 1 (Nurr1) in expression and function can contribute to neurodegeneration of dopaminergic neurons and occurrence of Parkinson's disease (PD). However, its related mechanism in PD is still unknown. In this study, we found that Nurr1 was down-regulated and CCL2 was up-regulated in PD patients and PD mice. CCL2 promoted apoptosis and secretion of TNF-α and IL-1β in SH-SY5Y cells and inhibited cell viability while knockdown of CCL2 exerted the opposite effects. Nurr1 overexpression inhibited apoptosis, the release of TNF-α and IL-1β and promoted viability in α-Syn-treated SH-SY5Y cells, which was markedly promoted by CCL2more » antibody and dramatically reversed by CCL2. Nurr1 overexpression negatively regulated CCL2 expression in vivo and in vitro. Furthermore, Nurr1 overexpression remarkably relieved MPTP-induced movement disorder and spatial memory deficits and played neuroprotective and anti-inflammatory roles in MPTP-induced PD mice by down-regulating CCL2 in vivo. In conclusion, Nurr1 overexpression exerts neuroprotective and anti-inflammatory roles via down-regulating CCL2 in both in vivo and in vitro PD models, contributing to developing mechanism-based and neuroprotective strategies against PD. - Highlights: • Nurr1 was down-regulated and CCL2 was up-regulated in PD patients and PD mice. • Nurr1 overexpression inhibited apoptosis, release of TNF-α and IL-1β and promoted viability in α-Syn-treated SH-SY5Y cells. • CCL2 reversed the effect of Nurr1 overexpression on apoptosis, inflammatory cytokines secretion and viability. • Nurr1 overexpression negatively regulated CCL2 expression in vivo and in vitro. • Nurr1 overexpression remarkably relieved MPTP-induced movement disorder and spatial memory deficits.« less

Involvement of SIRT1 in hypoxic down-regulation of c-Myc and β-catenin and hypoxic preconditioning effect of polyphenols

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

Hong, Kyung-Soo; Research Center for Ischemic Tissue regeneration, Pusan National University School of Medicine, Yangsan; Park, Jun-Ik

2012-03-01

SIRT1 has been found to function as a Class III deacetylase that affects the acetylation status of histones and other important cellular nonhistone proteins involved in various cellular pathways including stress responses and apoptosis. In this study, we investigated the role of SIRT1 signaling in the hypoxic down-regulations of c-Myc and β-catenin and hypoxic preconditioning effect of the red wine polyphenols such as piceatannol, myricetin, quercetin and resveratrol. We found that the expression of SIRT1 was significantly increased in hypoxia-exposed or hypoxic preconditioned HepG2 cells, which was closely associated with the up-regulation of HIF-1α and down-regulation of c-Myc and β-cateninmore » expression via deacetylation of these proteins. In addition, blockade of SIRT1 activation using siRNA or amurensin G, a new potent SIRT1 inhibitor, abolished hypoxia-induced HIF-1α expression but increased c-Myc and β-catenin expression. SIRT1 was also found to stabilize HIF-1α protein and destabilize c-Myc, β-catenin and PHD2 under hypoxia. We also found that myricetin, quercetin, piceatannol and resveratrol up-regulated HIF-1α and down-regulated c-Myc, PHD2 and β-catenin expressions via SIRT1 activation, in a manner that mimics hypoxic preconditioning. This study provides new insights of the molecular mechanisms of hypoxic preconditioning and suggests that polyphenolic SIRT1 activators could be used to mimic hypoxic/ischemic preconditioning. -- Graphical abstract: Polyphenols mimicked hypoxic preconditioning by up-regulating HIF-1α and SIRT1 and down-regulating c-Myc, PHD2, and β-catenin. HepG2 cells were pretreated with the indicated doses of myricetin (MYR; A), quercetin (QUR; B), or piceatannol (PIC; C) for 4 h and then exposed to hypoxia for 4 h. Levels of HIF-1α, SIRT1, c-Myc, β-catenin, and PHD2 were determined by western blot analysis. The data are representative of three individual experiments. Highlights: ► SIRT1 expression is increased in hypoxia-exposed or hypoxic preconditioned cells. ► SIRT1 deacetylates c-Myc and β-catenin ► HIF-1α is up-regulated by down-regulation of c-Myc and β-catenin expression. ► Polyphenolic SIRT1 activators mimics hypoxic preconditioning.« less

Down-regulated non-coding RNA (lncRNA-ANCR) promotes osteogenic differentiation of periodontal ligament stem cells.

PubMed

Jia, Qian; Jiang, Wenkai; Ni, Longxing

2015-02-01

Our studies aimed to figure out how anti-differentiation noncoding RNA (ANCR) regulates the proliferation and osteogenic differentiation of periodontal ligament stem cells (PDLSCs). In this study, we used lentivirus infection to down-regulate the expression of ANCR in PDLSCs. Then we compared the proliferation of control cells and PDLSC/ANCR-RNAi cells by Cell Counting Kit-8. And the osteogenic differentiation of control cells and PDLSC/ANCR-RNAi cells were evaluated by Alkaline phosphatase (ALP) activity quantification and Alizarin red staining. WNT inhibitor was used to analyze the relationship between ANCR and canonical WNT signalling pathway. The expression of osteogenic differentiation marker mRNAs, DKK1, GSK3-β and β-catenin were evaluated by qRT-PCR. The results showed that down-regulated ANCR promoted proliferation of PDLSCs. Down-regulated ANCR also promoted osteogenic differentiation of PDLSCs by up-regulating osteogenic differentiation marker genes. After the inhibition of canonical WNT signalling pathway, the osteogenic differentiation of PDLSC/ANCR-RNAi cells was inhibited too. qRT-PCR results also demonstrated that canonical WNT signalling pathway was activated for ANCR-RNAi on PDLSCs during the procedure of proliferation and osteogenic induction. These results indicated that ANCR was a key regulator of the proliferation and osteogenic differentiation of PDLSCs, and its regulating effects was associated with the canonical WNT signalling pathway, thus offering a new target for oral stem cell differentiation studies that could also facilitate oral tissue engineering. Copyright © 2014. Published by Elsevier Ltd.

miR-34a screened by miRNA profiling negatively regulates Wnt/β-catenin signaling pathway in Aflatoxin B1 induced hepatotoxicity

PubMed Central

Zhu, Liye; Gao, Jing; Huang, Kunlun; Luo, Yunbo; Zhang, Boyang; Xu, Wentao

2015-01-01

Aflatoxin-B1 (AFB1), a hepatocarcinogenic mycotoxin, was demonstrated to induce the high rate of hepatocellular carcinoma (HCC). MicroRNAs (miRNAs) participate in the regulation of several biological processes in HCC. However, the function of miRNAs in AFB1-induced HCC has received a little attention. Here, we applied Illumina deep sequencing technology for high-throughout profiling of microRNAs in HepG2 cells lines after treatment with AFB1. Analysis of the differential expression profile of miRNAs in two libraries, we identified 9 known miRNAs and 1 novel miRNA which exhibited abnormal expression. KEGG analysis indicated that predicted target genes of differentially expressed miRNAs are involved in cancer-related pathways. Down-regulated of Drosha, DGCR8 and Dicer 1 indicated an impairment of miRNA biogenesis in response to AFB1. miR-34a was up-regulated significantly, down-regulating the expression of Wnt/β-catenin signaling pathway by target gene β-catenin. Anti-miR-34a can significantly relieved the down-regulated β-catenin and its downstream genes, c-myc and Cyclin D1, and the S-phase arrest in cell cycle induced by AFB1 can also be relieved. These results suggested that AFB1 might down-regulate Wnt/β-catenin signaling pathway in HepG2 cells by up-regulating miR-34a, which may involve in the mechanism of liver tumorigenesis. PMID:26567713

Negative regulation of DAB2IP by Akt and SCFFbw7 pathways.

PubMed

Dai, Xiangping; North, Brian J; Inuzuka, Hiroyuki

2014-05-30

Deletion of ovarian carcinoma 2/disabled homolog 2 (DOC-2/DAB2) interacting protein (DAB2IP), is a tumor suppressor that serves as a scaffold protein involved in coordinately regulating cell proliferation, survival and apoptotic pathways. DAB2IP is epigenetically down-regulated in a variety of tumors through the action of the histone methyltransferase EZH2. Although DAB2IP is transcriptionally down-regulated in a variety of tumors, it remains unclear if other mechanisms contribute to functional inactivation of DAB2IP. Here we demonstrate that DAB2IP can be functionally down-regulated by two independent mechanisms. First, we identified that Akt1 can phosphorylate DAB2IP on S847, which regulates the interaction between DAB2IP and its effector molecules H-Ras and TRAF2. Second, we demonstrated that DAB2IP can be degraded in part through ubiquitin-proteasome pathway by SCF(Fbw7). DAB2IP harbors two Fbw7 phosho-degron motifs, which can be regulated by the kinase, CK1δ. Our data hence indicate that in addition to epigenetic down-regulation, two additional pathways can functional inactivate DAB2IP. Given that DAB2IP has previously been identified to possess direct causal role in tumorigenesis and metastasis, our data indicate that a variety of pathways may pass through DAB2IP to govern cancer development, and therefore highlight DAB2IP agonists as potential therapeutic approaches for future anti-cancer drug development.

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

Li, Mi; Pu, Yunqiao; Yoo, Chang Geun

The native recalcitrance of plants hinders the biomass conversion process using current biorefinery techniques. Down-regulation of the caffeic acid O-methyltransferase (COMT) gene in the lignin biosynthesis pathway of switchgrass reduced the thermochemical and biochemical conversion recalcitrance of biomass. Due to potential environmental influences on lignin biosynthesis and deposition, studying the consequences of physicochemical changes in field-grown plants without pretreatment is essential to evaluate the performance of lignin-altered plants. In this study, we determined the chemical composition, cellulose crystallinity and the degree of its polymerization, molecular weight of hemicellulose, and cellulose accessibility of cell walls in order to better understand themore » fundamental features of why biomass is recalcitrant to conversion without pretreatment. The most important is to investigate whether traits and features are stable in the dynamics of field environmental effects over multiple years.« less

A metabolic switch controls intestinal differentiation downstream of Adenomatous polyposis coli (APC).

PubMed

Sandoval, Imelda T; Delacruz, Richard Glenn C; Miller, Braden N; Hill, Shauna; Olson, Kristofor A; Gabriel, Ana E; Boyd, Kevin; Satterfield, Christeena; Remmen, Holly Van; Rutter, Jared; Jones, David A

2017-04-11

Elucidating signaling pathways that regulate cellular metabolism is essential for a better understanding of normal development and tumorigenesis. Recent studies have shown that mitochondrial pyruvate carrier 1 (MPC1) , a crucial player in pyruvate metabolism, is downregulated in colon adenocarcinomas. Utilizing zebrafish to examine the genetic relationship between MPC1 and Adenomatous polyposis coli (APC), a key tumor suppressor in colorectal cancer, we found that apc controls the levels of mpc1 and that knock down of mpc1 recapitulates phenotypes of impaired apc function including failed intestinal differentiation. Exogenous human MPC1 RNA rescued failed intestinal differentiation in zebrafish models of apc deficiency. Our data demonstrate a novel role for apc in pyruvate metabolism and that pyruvate metabolism dictates intestinal cell fate and differentiation decisions downstream of apc .

NUDT2 Disruption Elevates Diadenosine Tetraphosphate (Ap4A) and Down-Regulates Immune Response and Cancer Promotion Genes

PubMed Central

Marriott, Andrew S.; Vasieva, Olga; Fang, Yongxiang; Copeland, Nikki A.; McLennan, Alexander G.; Jones, Nigel J.

2016-01-01

Regulation of gene expression is one of several roles proposed for the stress-induced nucleotide diadenosine tetraphosphate (Ap4A). We have examined this directly by a comparative RNA-Seq analysis of KBM-7 chronic myelogenous leukemia cells and KBM-7 cells in which the NUDT2 Ap4A hydrolase gene had been disrupted (NuKO cells), causing a 175-fold increase in intracellular Ap4A. 6,288 differentially expressed genes were identified with P < 0.05. Of these, 980 were up-regulated and 705 down-regulated in NuKO cells with a fold-change ≥ 2. Ingenuity® Pathway Analysis (IPA®) was used to assign these genes to known canonical pathways and functional networks. Pathways associated with interferon responses, pattern recognition receptors and inflammation scored highly in the down-regulated set of genes while functions associated with MHC class II antigens were prominent among the up-regulated genes, which otherwise showed little organization into major functional gene sets. Tryptophan catabolism was also strongly down-regulated as were numerous genes known to be involved in tumor promotion in other systems, with roles in the epithelial-mesenchymal transition, proliferation, invasion and metastasis. Conversely, some pro-apoptotic genes were up-regulated. Major upstream factors predicted by IPA® for gene down-regulation included NFκB, STAT1/2, IRF3/4 and SP1 but no major factors controlling gene up-regulation were identified. Potential mechanisms for gene regulation mediated by Ap4A and/or NUDT2 disruption include binding of Ap4A to the HINT1 co-repressor, autocrine activation of purinoceptors by Ap4A, chromatin remodeling, effects of NUDT2 loss on transcript stability, and inhibition of ATP-dependent regulatory factors such as protein kinases by Ap4A. Existing evidence favors the last of these as the most probable mechanism. Regardless, our results suggest that the NUDT2 protein could be a novel cancer chemotherapeutic target, with its inhibition potentially exerting strong anti-tumor effects via multiple pathways involving metastasis, invasion, immunosuppression and apoptosis. PMID:27144453

NUDT2 Disruption Elevates Diadenosine Tetraphosphate (Ap4A) and Down-Regulates Immune Response and Cancer Promotion Genes.

PubMed

Marriott, Andrew S; Vasieva, Olga; Fang, Yongxiang; Copeland, Nikki A; McLennan, Alexander G; Jones, Nigel J

2016-01-01

Regulation of gene expression is one of several roles proposed for the stress-induced nucleotide diadenosine tetraphosphate (Ap4A). We have examined this directly by a comparative RNA-Seq analysis of KBM-7 chronic myelogenous leukemia cells and KBM-7 cells in which the NUDT2 Ap4A hydrolase gene had been disrupted (NuKO cells), causing a 175-fold increase in intracellular Ap4A. 6,288 differentially expressed genes were identified with P < 0.05. Of these, 980 were up-regulated and 705 down-regulated in NuKO cells with a fold-change ≥ 2. Ingenuity® Pathway Analysis (IPA®) was used to assign these genes to known canonical pathways and functional networks. Pathways associated with interferon responses, pattern recognition receptors and inflammation scored highly in the down-regulated set of genes while functions associated with MHC class II antigens were prominent among the up-regulated genes, which otherwise showed little organization into major functional gene sets. Tryptophan catabolism was also strongly down-regulated as were numerous genes known to be involved in tumor promotion in other systems, with roles in the epithelial-mesenchymal transition, proliferation, invasion and metastasis. Conversely, some pro-apoptotic genes were up-regulated. Major upstream factors predicted by IPA® for gene down-regulation included NFκB, STAT1/2, IRF3/4 and SP1 but no major factors controlling gene up-regulation were identified. Potential mechanisms for gene regulation mediated by Ap4A and/or NUDT2 disruption include binding of Ap4A to the HINT1 co-repressor, autocrine activation of purinoceptors by Ap4A, chromatin remodeling, effects of NUDT2 loss on transcript stability, and inhibition of ATP-dependent regulatory factors such as protein kinases by Ap4A. Existing evidence favors the last of these as the most probable mechanism. Regardless, our results suggest that the NUDT2 protein could be a novel cancer chemotherapeutic target, with its inhibition potentially exerting strong anti-tumor effects via multiple pathways involving metastasis, invasion, immunosuppression and apoptosis.

Smad4 mediated BMP2 signal is essential for the regulation of GATA4 and Nkx2.5 by affecting the histone H3 acetylation in H9c2 cells

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

Si, Lina; Shi, Jin; Gao, Wenqun

2014-07-18

Highlights: • BMP2 can upregulated cardiac related gene GATA4, Nkx2.5, MEF2c and Tbx5. • Inhibition of Smad4 decreased BMP2-induced hyperacetylation of histone H3. • Inhibition of Smad4 diminished BMP2-induced overexpression of GATA4 and Nkx2.5. • Inhibition of Smad4 decreased hyperacetylated H3 in the promoter of GATA4 and Nkx2.5. • Smad4 is essential for BMP2 induced hyperacetylated histone H3. - Abstract: BMP2 signaling pathway plays critical roles during heart development, Smad4 encodes the only common Smad protein in mammals, which is a pivotal nuclear mediator. Our previous studies showed that BMP2 enhanced the expression of cardiac transcription factors in part bymore » increasing histone H3 acetylation. In the present study, we tested the hypothesis that Smad4 mediated BMP2 signaling pathway is essential for the expression of cardiac core transcription factors by affecting the histone H3 acetylation. We successfully constructed a lentivirus-mediated short hairpin RNA interference vector targeting Smad4 (Lv-Smad4) in rat H9c2 embryonic cardiac myocytes (H9c2 cells) and demonstrated that it suppressed the expression of the Smad4 gene. Cultured H9c2 cells were transfected with recombinant adenoviruses expressing human BMP2 (AdBMP2) with or without Lv-Smad4. Quantitative real-time RT-PCR analysis showed that knocking down of Smad4 substantially inhibited both AdBMP2-induced and basal expression levels of cardiac transcription factors GATA4 and Nkx2.5, but not MEF2c and Tbx5. Similarly, chromatin immunoprecipitation (ChIP) analysis showed that knocking down of Smad4 inhibited both AdBMP2-induced and basal histone H3 acetylation levels in the promoter regions of GATA4 and Nkx2.5, but not of Tbx5 and MEF2c. In addition, Lv-Smad4 selectively suppressed AdBMP2-induced expression of HAT p300, but not of HAT GCN5 in H9c2 cells. The data indicated that inhibition of Smad4 diminished both AdBMP2 induced and basal histone acetylation levels in the promoter regions of GATA4 and Nkx2.5, suggesting that Smad4 mediated BMP2 signaling pathway was essential for the regulation of GATA4 and Nkx2.5 by affecting the histone H3 acetylation in H9c2 cells.« less

Substantiation of artificial composite-structure roof construction in top-down cut-and-fill stoping

NASA Astrophysics Data System (ADS)

Rukavishnikov, GD; Neverov, SA; Neverov, AA

2018-03-01

It has been found efficient and safe to use top-down cut-and-fill stoping with saving of the artificial backfill cost and material through the use of a solid nonuniform material composed of two components (layers). It is shown that the artificial roof can be advanced after a stope without essential change in the stope condition as compared with the classical top-down slice method, which provides higher safety of mining.

Cognitive Control of Movement in Down Syndrome

ERIC Educational Resources Information Center

Brunamonti, Emiliano; Pani, Pierpaolo; Papazachariadis, Odysseas; Onorati, Paolo; Albertini, Giorgio; Ferraina, Stefano

2011-01-01

Inhibition of inappropriate responses allows to shape the motor behavior accordingly to the context in which a subject acts and is an essential executive function. Inhibition has been poorly investigated in Down Syndrome (DS) patients. We tested, using a countermanding task, the inhibitory control in a group of DS patients and in a group of…

High-Level Carbapenem Resistance in a Klebsiella pneumoniae Clinical Isolate Is Due to the Combination of blaACT-1 β-Lactamase Production, Porin OmpK35/36 Insertional Inactivation, and Down-Regulation of the Phosphate Transport Porin PhoE

PubMed Central

Kaczmarek, Frank M.; Dib-Hajj, Fadia; Shang, Wenchi; Gootz, Thomas D.

2006-01-01

Clinical isolates of Klebsiella pneumoniae resistant to carbapenems and essentially all other antibiotics (multidrug resistant) are being isolated from some hospitals in New York City with increasing frequency. A highly related pair of K. pneumoniae strains isolated on the same day from one patient in a hospital in New York City were studied for antibiotic resistance. One (KP-2) was resistant to imipenem, meropenem, and sulopenem (MICs of 16 to 32 μg/ml) while the other (KP-1) was susceptible (MIC of 0.5 μg/ml); both contained the blaACT-1, blaSHV-1, and blaTEM-1 β-lactamases. blaACT-1 in both strains was encoded on a large ∼150-kb plasmid. Both isolates contained an identical class 1 integron encoding resistance to aminoglycosides and chloramphenicol. They each had identical insertions in ompK35 and ompK36, resulting in disruption of these key porin genes. The carbapenem-resistant and -susceptible isolates were extensively studied for differences in the structural and regulatory genes for the operons acrRAB, marORAB, romA-ramA, soxRS, micF, micC, phoE, phoBR, rpoS, and hfq. No changes were detected between the isolates except for a significant down-regulation of ompK37, phoB, and phoE in KP-2 as deduced from reverse transcription-PCR analysis of mRNA and polyacrylamide gel electrophoresis separation of outer membrane proteins. Backcross analysis was conducted using the wild-type phoE gene cloned into the vector pGEM under regulation of its native promoter as well as the lacZ promoter following transformation into the resistant KP-2 isolate. The wild-type gene reversed carbapenem resistance only when under control of the heterologous lacZ promoter. In the background of ompK35-ompK36 gene disruption, the up-regulation of phoE in KP-1 apparently compensated for porin loss and conferred carbapenem susceptibility. Down-regulation of phoE in KP-2 may represent the normal state of this gene, or it may have been selected from KP-1 in vivo under antibiotic pressure, generating the carbapenem-resistant clone. This is the first study in the Enterobacteriaceae where expression of the phosphate-regulated PhoE porin has been associated with resistance to antimicrobials. Our results with this pair of Klebsiella clinical isolates highlight the complex and evolving nature of multiple drug resistance in this species. PMID:17005822

High-level carbapenem resistance in a Klebsiella pneumoniae clinical isolate is due to the combination of bla(ACT-1) beta-lactamase production, porin OmpK35/36 insertional inactivation, and down-regulation of the phosphate transport porin phoe.

PubMed

Kaczmarek, Frank M; Dib-Hajj, Fadia; Shang, Wenchi; Gootz, Thomas D

2006-10-01

Clinical isolates of Klebsiella pneumoniae resistant to carbapenems and essentially all other antibiotics (multidrug resistant) are being isolated from some hospitals in New York City with increasing frequency. A highly related pair of K. pneumoniae strains isolated on the same day from one patient in a hospital in New York City were studied for antibiotic resistance. One (KP-2) was resistant to imipenem, meropenem, and sulopenem (MICs of 16 to 32 microg/ml) while the other (KP-1) was susceptible (MIC of 0.5 microg/ml); both contained the bla(ACT-1), bla(SHV-1), and bla(TEM-1) beta-lactamases. bla(ACT-1) in both strains was encoded on a large approximately 150-kb plasmid. Both isolates contained an identical class 1 integron encoding resistance to aminoglycosides and chloramphenicol. They each had identical insertions in ompK35 and ompK36, resulting in disruption of these key porin genes. The carbapenem-resistant and -susceptible isolates were extensively studied for differences in the structural and regulatory genes for the operons acrRAB, marORAB, romA-ramA, soxRS, micF, micC, phoE, phoBR, rpoS, and hfq. No changes were detected between the isolates except for a significant down-regulation of ompK37, phoB, and phoE in KP-2 as deduced from reverse transcription-PCR analysis of mRNA and polyacrylamide gel electrophoresis separation of outer membrane proteins. Backcross analysis was conducted using the wild-type phoE gene cloned into the vector pGEM under regulation of its native promoter as well as the lacZ promoter following transformation into the resistant KP-2 isolate. The wild-type gene reversed carbapenem resistance only when under control of the heterologous lacZ promoter. In the background of ompK35-ompK36 gene disruption, the up-regulation of phoE in KP-1 apparently compensated for porin loss and conferred carbapenem susceptibility. Down-regulation of phoE in KP-2 may represent the normal state of this gene, or it may have been selected from KP-1 in vivo under antibiotic pressure, generating the carbapenem-resistant clone. This is the first study in the Enterobacteriaceae where expression of the phosphate-regulated PhoE porin has been associated with resistance to antimicrobials. Our results with this pair of Klebsiella clinical isolates highlight the complex and evolving nature of multiple drug resistance in this species.

Effects of bisphenol A on the expression of cytochrome P450 aromatase (CYP19) in human fetal osteoblastic and granulosa cell-like cell lines.

PubMed

Watanabe, Masatada; Ohno, Shuji; Nakajin, Shizuo

2012-04-05

The effects of bisphenol A (BPA), an endocrine disruptor, on aromatase (CYP19) expression in human osteoblastic (SV-HFO) and ovarian granulosa-like (KGN) cell lines were examined. CYP19 enzyme activity was suppressed in the presence of BPA in a dose-dependent fashion in both cell lines. CYP19 gene transcript expression, as well as activities of promoter I.4 in SV-HFO and promoter II in KGN, was down-regulated by BPA, suggesting that BPA affects CYP19 at the gene-expression level. These data and the previous finding that BPA induced the down-regulation of promoter I.1 activity within the human placental cell line suggest that there may be a conserved signaling pathway that down-regulates CYP19 expression in response to BPA in both cell lines. Additionally, differences between promoter I.4 and II suggest that there may be cell- and promoter-specific down-regulating mechanisms downstream from the actions of BPA. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Effect of inhibition of the ROCK isoform on RT2 malignant glioma cells.

PubMed

Inaba, Nobuharu; Ishizawa, Sho; Kimura, Masaki; Fujioka, Kouki; Watanabe, Michiko; Shibasaki, Toshiaki; Manome, Yoshinobu

2010-09-01

Malignant glioma is one of the most intractable diseases in the human body. Rho-kinase (ROCK) is overexpressed and has been proposed as the main cause for the refractoriness of the disease. Since efficacious treatment is required, this study investigated the effect of inhibition of ROCK isoforms. The short hairpin RNA transcription vector was transfected into the RT2 rat glioma cell line and the characteristics of the cells were investigated. The effect of nimustine hydrochloride (ACNU) anti-neoplastic agent on cells was also measured. Inhibition of ROCK isoforms did not alter cell growth. Cell cycle analysis revealed that ROCK1 down-regulation reduced the G(0) phase population and ROCK2 down-regulation reduced the G(2)/M phase population. When ROCK1-down-regulated cells were exposed to ACNU, they demonstrated susceptibility to the agent. The roles of ROCK1 and ROCK2 may be different in glioma cells. Furthermore, the combination of ROCK1 down-regulation and an anti-neoplastic agent may be useful for the therapy of malignant glioma.

Role of Endogenous Cholecystokinin on Growth of Human Pancreatic Cancer

PubMed Central

Matters, Gail L.; McGovern, Christopher; Harms, John F.; Markovic, Kevin; Anson, Krystal; Jayakumar, Calpurnia; Martenis, Melissa; Awad, Christina; Smith, Jill P.

2012-01-01

Cholecystokinin (CCK) and gastrin stimulate growth of pancreatic cancer. Although down regulation of gastrin inhibits growth of pancreatic cancer, the contribution of endogenous CCK to tumor growth is unknown. The purpose of this study was to evaluate the role of endogenous CCK on autocrine growth of pancreatic cancer. Pancreatic cancer cell lines were analyzed for CCK mRNA and peptide expression by real time RT-PCR and radioimmunoassay, respectively. The effect of endogenous CCK on growth was evaluated by treating cancer cells with CCK neutralizing antibodies and by down regulating CCK mRNA by RNAi. Wild type pancreatic cancer cells expressed significantly lower CCK mRNA and peptide levels than gastrin. Neither treatment of pancreatic cancer cells with CCK antibodies nor the down regulation of CCK mRNA and peptide by shRNAs altered growth in vitro or in vivo. Conversely, when gastrin mRNA expression was down regulated, the same cells failed to produce tumors in spite of having sustained levels of endogenous CCK. Pancreatic cancer cells produce CCK and gastrin; however, the autocrine production of gastrin is more important for stimulating tumor growth. PMID:21186400

Subchronic Exposure to Arsenic Represses the TH/TRβ1-CaMK IV Signaling Pathway in Mouse Cerebellum.

PubMed

Guan, Huai; Li, Shuangyue; Guo, Yanjie; Liu, Xiaofeng; Yang, Yi; Guo, Jinqiu; Li, Sheng; Zhang, Cong; Shang, Lixin; Piao, Fengyuan

2016-01-26

We previously reported that arsenic (As) impaired learning and memory by down-regulating calmodulin-dependent protein kinase IV (CaMK IV) in mouse cerebellum. It has been documented that the thyroid hormone receptor (TR)/retinoid X receptor (RXR) heterodimer and thyroid hormone (TH) may be involved in the regulation of CaMK IV. To investigate whether As affects the TR/RXR heterodimer and TH, we determined As concentration in serum and cerebellum, 3,5,3'-triiodothyronine (T3) and thyroxin (T4) levels in serum, and expression of CaMK IV, TR and RXR in cerebellum of mice exposed to As. Cognition function was examined by the step-down passive avoidance task and Morris water maze (MWM) tests. Morphology of the cerebellum was observed by Hematoxylin-Eosin staining under light microscope. Our results showed that the concentrations of As in the serum and cerebellum of mice both increased with increasing As-exposure level. A significant positive correlation was found between the two processes. Adeficit in learning and memory was found in the exposed mice. Abnormal morphologic changes of Purkinje cells were observed in cerebellum of the exposed mice. Moreover, the cerebellar expressions of CaMK IV protein and the TRβ gene, and TRβ1 protein were significantly lower in As-exposed mice than those in controls. Subchronic exposure to As appears to increase its level in serum and cerebella of mice, impairing learning and memory and down-regulating expression of TRβ1 as well as down-stream CaMK IV. It is also suggested that the increased As may be responsible for down-regulation of TRβ1 and CaMK IV in cerebellum and that the down-regulated TRβ1 may be involved in As-induced impairment of learning and memory via inhibiting CaMK IV and its down-stream pathway.

Transgenic Bt Cotton Does Not Disrupt the Top-Down Forces Regulating the Cotton Aphid in Central China

PubMed Central

Yao, Yong-Sheng; Han, Peng; Niu, Chang-Ying; Dong, Yong-Cheng; Gao, Xi-Wu; Cui, Jin-Jie; Desneux, Nicolas

2016-01-01

Top-down force is referred to arthropod pest management delivered by the organisms from higher trophic levels. In the context of prevalent adoption of transgenic Bt crops that produce insecticidal Cry proteins derived from Bacillus thuringiensis (Bt), it still remains elusive whether the top-down forces are affected by the insect-resistant traits that introduced into the Bt crops. We explored how Bt cotton affect the strength of top-down forces via arthropod natural enemies in regulating a non-target pest species, the cotton aphid Aphis gossypii Glover, using a comparative approach (i.e. Bt cotton vs. conventional cotton) under field conditions. To determine top-down forces, we manipulated predation/parasitism exposure of the aphid to their natural enemies using exclusion cages. We found that the aphid population growth was strongly suppressed by the dominant natural enemies including Coccinellids, spiders and Aphidiines parasitoids. Coccinellids, spiders and the assemblage of other arthropod natural enemies (mainly lacewings and Hemipteran bugs) are similarly abundant in both plots, but with the parasitoid mummies less abundant in Bt cotton plots compared to the conventional cotton plots. However, the lower abundance of parasitoids in Bt cotton plots alone did not translate into differential top-down control on A. gossypii populations compared to conventional ones. Overall, the top-down forces were equally strong in both plots. We conclude that transgenic Bt cotton does not disrupt the top-down forces regulating the cotton aphid in central China. PMID:27870914

The C-terminal domain of Nrf1 negatively regulates the full-length CNC-bZIP factor and its shorter isoform LCR-F1/Nrf1β; both are also inhibited by the small dominant-negative Nrf1γ/δ isoforms that down-regulate ARE-battery gene expression.

PubMed

Zhang, Yiguo; Qiu, Lu; Li, Shaojun; Xiang, Yuancai; Chen, Jiayu; Ren, Yonggang

2014-01-01

The C-terminal domain (CTD, aa 686-741) of nuclear factor-erythroid 2 p45-related factor 1 (Nrf1) shares 53% amino acid sequence identity with the equivalent Neh3 domain of Nrf2, a homologous transcription factor. The Neh3 positively regulates Nrf2, but whether the Neh3-like (Neh3L) CTD of Nrf1 has a similar role in regulating Nrf1-target gene expression is unknown. Herein, we report that CTD negatively regulates the full-length Nrf1 (i.e. 120-kDa glycoprotein and 95-kDa deglycoprotein) and its shorter isoform LCR-F1/Nrf1β (55-kDa). Attachment of its CTD-adjoining 112-aa to the C-terminus of Nrf2 yields the chimaeric Nrf2-C112Nrf1 factor with a markedly decreased activity. Live-cell imaging of GFP-CTD reveals that the extra-nuclear portion of the fusion protein is allowed to associate with the endoplasmic reticulum (ER) membrane through the amphipathic Neh3L region of Nrf1 and its basic c-tail. Thus removal of either the entire CTD or the essential Neh3L portion within CTD from Nrf1, LCR-F1/Nrf1β and Nrf2-C112Nrf1, results in an increase in their transcriptional ability to regulate antioxidant response element (ARE)-driven reporter genes. Further examinations unravel that two smaller isoforms, 36-kDa Nrf1γ and 25-kDa Nrf1δ, act as dominant-negative inhibitors to compete against Nrf1, LCR-F1/Nrf1β and Nrf2. Relative to Nrf1, LCR-F1/Nrf1β is a weak activator, that is positively regulated by its Asn/Ser/Thr-rich (NST) domain and acidic domain 2 (AD2). Like AD1 of Nrf1, both AD2 and NST domain of LCR-F1/Nrf1β fused within two different chimaeric contexts to yield Gal4D:Nrf1β607 and Nrf1β:C270Nrf2, positively regulate their transactivation activity of cognate Gal4- and Nrf2-target reporter genes. More importantly, differential expression of endogenous ARE-battery genes is attributable to up-regulation by Nrf1 and LCR-F1/Nrf1β and down-regulation by Nrf1γ and Nrf1δ.

40 CFR 86.1335-90 - Cool-down procedure.

Code of Federal Regulations, 2012 CFR

2012-07-01

... cold cycle exhaust emission test may begin after a cool-down only when the engine oil and water... Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures § 86.1335-90 Cool-down procedure. (a) This cool-down procedure applies to Otto-cycle and diesel engines...

40 CFR 86.1335-90 - Cool-down procedure.

Code of Federal Regulations, 2011 CFR

2011-07-01

... cold cycle exhaust emission test may begin after a cool-down only when the engine oil and water... Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures § 86.1335-90 Cool-down procedure. (a) This cool-down procedure applies to Otto-cycle and diesel engines...

40 CFR 86.1335-90 - Cool-down procedure.

Code of Federal Regulations, 2013 CFR

2013-07-01

... cold cycle exhaust emission test may begin after a cool-down only when the engine oil and water... Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures § 86.1335-90 Cool-down procedure. (a) This cool-down procedure applies to Otto-cycle and diesel engines...

Transcriptome analysis of phosphorus stress responsiveness in the seedlings of Dongxiang wild rice (Oryza rufipogon Griff.).

PubMed

Deng, Qian-Wen; Luo, Xiang-Dong; Chen, Ya-Ling; Zhou, Yi; Zhang, Fan-Tao; Hu, Biao-Lin; Xie, Jian-Kun

2018-03-15

Low phosphorus availability is a major factor restricting rice growth. Dongxiang wild rice (Oryza rufipogon Griff.) has many useful genes lacking in cultivated rice, including stress resistance to phosphorus deficiency, cold, salt and drought, which is considered to be a precious germplasm resource for rice breeding. However, the molecular mechanism of regulation of phosphorus deficiency tolerance is not clear. In this study, cDNA libraries were constructed from the leaf and root tissues of phosphorus stressed and untreated Dongxiang wild rice seedlings, and transcriptome sequencing was performed with the goal of elucidating the molecular mechanisms involved in phosphorus stress response. The results indicated that 1184 transcripts were differentially expressed in the leaves (323 up-regulated and 861 down-regulated) and 986 transcripts were differentially expressed in the roots (756 up-regulated and 230 down-regulated). 43 genes were up-regulated both in leaves and roots, 38 genes were up-regulated in roots but down-regulated in leaves, and only 2 genes were down-regulated in roots but up-regulated in leaves. Among these differentially expressed genes, the detection of many transcription factors and functional genes demonstrated that multiple regulatory pathways were involved in phosphorus deficiency tolerance. Meanwhile, the differentially expressed genes were also annotated with gene ontology terms and key pathways via functional classification and Kyoto Encyclopedia of Gene and Genomes pathway mapping, respectively. A set of the most important candidate genes was then identified by combining the differentially expressed genes found in the present study with previously identified phosphorus deficiency tolerance quantitative trait loci. The present work provides abundant genomic information for functional dissection of the phosphorus deficiency resistance of Dongxiang wild rice, which will be help to understand the biological regulatory mechanisms of phosphorus deficiency tolerance in Dongxiang wild rice.

Zyflamend Sensitizes Tumor Cells to TRAIL-Induced Apoptosis Through Up-Regulation of Death Receptors and Down-Regulation of Survival Proteins: Role of ROS-Dependent CCAAT/Enhancer-Binding Protein-Homologous Protein Pathway

PubMed Central

Kim, Ji Hye; Park, Byoungduck; Gupta, Subash C.; Kannappan, Ramaswamy; Sung, Bokyung

2012-01-01

Abstract Aim: TNF (tumor necrosis factor)-related apoptosis-inducing ligand (TRAIL), is a selective killer of tumor cells, although its potential is limited by the development of resistance. In this article, we investigated whether the polyherbal preparation Zyflamend® can sensitize tumor cells to TRAIL. Results: We found that Zyflamend potentiated TRAIL-induced apoptosis in human cancer cells. Zyflamend manifested its effects through several mechanisms. First, it down-regulated the expression of cell survival proteins known to be linked to resistance to TRAIL. Second, Zyflamend up-regulated the expression of pro-apoptotic protein, Bax. Third, Zyflamend up-regulated the expression of death receptors (DRs) for TRAIL. Up-regulation of DRs was critical as gene-silencing of these receptors significantly reduced the effect of Zyflamend on TRAIL-induced apoptosis. The up-regulation of DRs was dependent on CCAAT/enhancer-binding protein-homologous protein (CHOP), as Zyflamend induced CHOP, its gene-silencing abolished the induction of receptors, and mutation of the CHOP binding site on DR5 promoter abolished Zyflamend-mediated DR5 transactivation. Zyflamend mediated its effects through reactive oxygen species (ROS), as ROS quenching reduced its effect. Further, Zyflamend induced DR5 and CHOP and down-regulated the expression of cell survival proteins in nude mice bearing human pancreatic cancer cells. Innovation: Zyflamend can sensitize tumor cells to TRAIL through modulation of multiple cell signaling mechanisms that are linked to ROS. Conclusion: Zyflamend potentiates TRAIL-induced apoptosis through the ROS-CHOP-mediated up-regulation of DRs, increase in pro-apoptotic protein and down-regulation of cell survival proteins. Antioxid. Redox Signal. 16, 413–427. PMID:22004570

Effects of Nickel, Chlorpyrifos and Their Mixture on the Dictyostelium discoideum Proteome

PubMed Central

Boatti, Lara; Robotti, Elisa; Marengo, Emilio; Viarengo, Aldo; Marsano, Francesco

2012-01-01

Mixtures of chemicals can have additive, synergistic or antagonistic interactions. We investigated the effects of the exposure to nickel, the organophosphate insecticide chlorpyrifos at effect concentrations (EC) of 25% and 50% and their binary mixture (Ec25 + EC25) on Dictyostelium discoideum amoebae based on lysosomal membrane stability (LMS). We treated D. discoideum with these compounds under controlled laboratory conditions and evaluated the changes in protein levels using a two-dimensional gel electrophoresis (2DE) proteomic approach. Nickel treatment at EC25 induced changes in 14 protein spots, 12 of which were down-regulated. Treatment with nickel at EC50 resulted in changes in 15 spots, 10 of which were down-regulated. Treatment with chlorpyrifos at EC25 induced changes in six spots, all of which were down-regulated; treatment with chlorpyrifos at EC50 induced changes in 13 spots, five of which were down-regulated. The mixture corresponding to EC25 of each compound induced changes in 19 spots, 13 of which were down-regulated. The data together reveal that a different protein expression signature exists for each treatment, and that only a few proteins are modulated in multiple different treatments. For a simple binary mixture, the proteomic response does not allow for the identification of each toxicant. The protein spots that showed significant differences were identified by mass spectrometry, which revealed modulations of proteins involved in metal detoxification, stress adaptation, the oxidative stress response and other cellular processes. PMID:23443088

(-)-Menthol biosynthesis and molecular genetics

NASA Astrophysics Data System (ADS)

Croteau, Rodney B.; Davis, Edward M.; Ringer, Kerry L.; Wildung, Mark R.

2005-12-01

(-)-Menthol is the most familiar of the monoterpenes as both a pure natural product and as the principal and characteristic constituent of the essential oil of peppermint ( Mentha x piperita). In this paper, we review the biosynthesis and molecular genetics of (-)-menthol production in peppermint. In Mentha species, essential oil biosynthesis and storage is restricted to the peltate glandular trichomes (oil glands) on the aerial surfaces of the plant. A mechanical method for the isolation of metabolically functional oil glands, has provided a system for precursor feeding studies to elucidate pathway steps, as well as a highly enriched source of the relevant biosynthetic enzymes and of their corresponding transcripts with which cDNA libraries have been constructed to permit cloning and characterization of key structural genes. The biosynthesis of (-)-menthol from primary metabolism requires eight enzymatic steps, and involves the formation and subsequent cyclization of the universal monoterpene precursor geranyl diphosphate to the parent olefin (-)-(4 S)-limonene as the first committed reaction of the sequence. Following hydroxylation at C3, a series of four redox transformations and an isomerization occur in a general “allylic oxidation-conjugate reduction” scheme that installs three chiral centers on the substituted cyclohexanoid ring to yield (-)-(1 R, 3 R, 4 S)-menthol. The properties of each enzyme and gene of menthol biosynthesis are described, as are their probable evolutionary origins in primary metabolism. The organization of menthol biosynthesis is complex in involving four subcellular compartments, and regulation of the pathway appears to reside largely at the level of gene expression. Genetic engineering to up-regulate a flux-limiting step and down-regulate a side route reaction has led to improvement in the composition and yield of peppermint oil.

Apigenin suppresses migration and invasion of transformed cells through down-regulation of C-X-C chemokine receptor 4 expression

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

Wang, Lei; Kuang, Lisha; Hitron, John Andrew

Environmental exposure to arsenic is known to cause various cancers. There are some potential relationships between cell malignant transformation and C-X-C chemokine receptor type 4 (CXCR4) expressions. Metastasis, one of the major characteristics of malignantly transformed cells, contributes to the high mortality of cells. CXCR4 and its natural chemokine ligand C-X-C motif ligand 12 (CXCL12) play a critical role in metastasis. Therefore, identification of nutritional factors which are able to inhibit CXCR4 is important for protection from environmental arsenic-induced carcinogenesis and for abolishing metastasis of malignantly transformed cells. The present study demonstrates that apigenin (4′,5,7-trihydroxyflavone), a natural dietary flavonoid, suppressedmore » CXCR4 expression in arsenic-transformed Beas-2B cells (B-AsT) and several other types of transformed/cancer cells in a dose- and time-dependent manner. Neither proteasome nor lysosome inhibitor had any effect in reducing the apigenin-induced down-regulation of CXCR4, indicating that apigenin-induced down-regulation of CXCR4 is not due to proteolytic degradation. The down-regulation of CXCR4 is mainly due to the inhibition of nuclear factor κB (NF-κB) transcriptional activity. Apigenin also abolished migration and invasion of transformed cells induced by CXCL12. In a xenograft mouse model, apigenin down-regulated CXCR4 expression and suppressed tumor growth. Taken together, our results show that apigenin is a novel inhibitor of CXCR4 expression. This dietary flavonoid has the potential to suppress migration and invasion of transformed cells and prevent environmental arsenic-induced carcinogenesis. - Highlights: • Apigenin has a potential in preventing environmental arsenic induced carcinogenesis. • Apigenin suppresses CXCR4 in malignant transformed cells in vitro and in vivo. • The down-regulation of CXCR4 is mainly due to inhibition of NF-κB activity.« less

PPARα, PPARγ and SREBP-1 pathways mediated waterborne iron (Fe)-induced reduction in hepatic lipid deposition of javelin goby Synechogobius hasta.

PubMed

Chen, Guang-Hui; Luo, Zhi; Chen, Feng; Shi, Xi; Song, Yu-Feng; You, Wen-Jing; Liu, Xu

2017-07-01

The 42-day experiment was conducted to investigate the effects and mechanism of waterborne Fe exposure influencing hepatic lipid deposition in Synechogobius hasta. For that purpose, S. hasta were exposed to four Fe concentrations (0 (control), 0.36, 0.72 and 1.07μM Fe) for 42days. On days 21 and 42, morphological parameters, hepatic lipid deposition and Fe contents, and activities and mRNA levels of enzymes and genes related to lipid metabolism, including lipogenic enzymes (6PGD, G6PD, ME, ICDH, FAS and ACC) and lipolytic enzymes (CPTI, HSL), were analyzed. With the increase of Fe concentration, hepatic Fe content tended to increase but HSI and lipid content tended to decrease. On day 21, Fe exposure down-regulated the lipogenic activities of 6PGD, G6PD, ICDH and FAS as well as the mRNA levels of G6PD, ACCa, FAS, SREBP-1 and PPARγ, but up-regulated CPT I, HSLa and PPARα mRNA levels. On day 42, Fe exposure down-regulated the lipogenic activities of 6PGD, G6PD, ICDH and FAS as well as the mRNA levels of 6PGD, ACCa, FAS and SREBP-1, but up-regulated CPT I, HSLa, PPARα and PPARγ mRNA levels. Using primary S. hasta hepatocytes, specific pathway inhibitors (GW6471 for PPARα and fatostatin for SREBP-1) and activator (troglitazone for PPARγ) were used to explore the signaling pathways of Fe reducing lipid deposition. The GW6471 attenuated the Fe-induced down-regulation of mRNA levels of 6PGD, G6PD, ME, FAS and ACCa, and attenuated the Fe-induced up-regulation of mRNA levels of CPT I, HSLa and PPARα. Compared with single Fe-incubated group, the mRNA levels of G6PD, ME, FAS, ACCa, ACCb and PPARγ were up-regulated while the CPT I mRNA levels were down-regulated after troglitazone pre-treatment; fatostatin pre-treatment down-regulated the mRNA levels of 6PGD, ME, FAS, ACCa, ACCb and SREBP-1, and increased the CPT I and HSLa mRNA levels. Based on these results above, our study indicated that Fe exposure reduced hepatic lipid deposition by down-regulating lipogenesis and up-regulating lipolysis, and PPARα, PPARγ and SREBP-1 pathways mediated the Fe-induced reduction of hepatic lipid deposition in S. hasta. Copyright © 2017 Elsevier Inc. All rights reserved.