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Sample records for drosophila confers increased

  1. Experimental evolution of defense against a competitive mold confers reduced sensitivity to fungal toxins but no increased resistance in Drosophila larvae.

    PubMed

    Trienens, Monika; Rohlfs, Marko

    2011-07-14

    Fungal secondary metabolites have been suggested to function as chemical defenses against insect antagonists, i.e. predators and competitors. Because insects and fungi often compete for dead organic material, insects may achieve protection against fungi by reducing sensitivity to fungal chemicals. This, in turn, may lead to increased resistance allowing insects better to suppress the spread of antagonistic but non-pathogenic microbes in their habitat. However, it remains controversial whether fungal toxins serve as a chemical shield that selects for insects that are less sensitive to toxins, and hence favors the evolution of insect resistance against microbial competitors. To examine the relationship between the ability to survive competition with toxic fungi, sensitivity to fungal toxins and resistance, we created fungal-selected (FS) replicated insect lines by exposing Drosophila melanogaster larvae to the fungal competitor Aspergillus nidulans over 26 insect generations. Compared to unselected control lines (UC), larvae from the FS lines had higher survival rates in the presence of A. nidulans indicating selection for increased protection against the fungal antagonist. In line with our expectation, FS lines were less susceptible to the A. nidulans mycotoxin Sterigmatocystin. Of particular interest is that evolved protection against A. nidulans and Sterigmatocytin was not correlated with increased insect survival in the presence of other fungi and mycotoxins. We found no evidence that FS lines were better at suppressing the expansion of fungal colonies but observed a trend towards a less detrimental effect of FS larvae on fungal growth. Antagonistic but non-pathogenic fungi favor insect variants better protected against the fungal chemical arsenal. This highlights the often proposed but experimentally underexplored importance of secondary metabolites in driving animal-fungus interactions. Instead of enhanced resistance, insect larvae tend to have evolved

  2. Optogenetic pacing in Drosophila melanogaster (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Alex, Aneesh; Li, Airong; Men, Jing; Jerwick, Jason; Tanzi, Rudolph E.; Zhou, Chao

    2016-03-01

    A non-invasive, contact-less cardiac pacing technology can be a powerful tool in basic cardiac research and in clinics. Currently, electrical pacing is the gold standard for cardiac pacing. Although highly effective in controlling the cardiac function, the invasive nature, non-specificity to cardiac tissues and possible tissue damage limits its capabilities. Optical pacing of heart is a promising alternative, which is non-invasive and more specific, has high spatial and temporal precision, and avoids shortcomings in electrical stimulation. Optical coherence tomography has been proved to be an effective technique in non-invasive imaging in vivo with ultrahigh resolution and imaging speed. In the last several years, non-invasive specific optical pacing in animal hearts has been reported in quail, zebrafish, and rabbit models. However, Drosophila Melanogaster, which is a significant model with orthologs of 75% of human disease genes, has rarely been studied concerning their optical pacing in heart. Here, we combined optogenetic control of Drosophila heartbeat with optical coherence microscopy (OCM) technique for the first time. The light-gated cation channel, channelrhodopsin-2 (ChR2) was specifically expressed by transgene as a pacemaker in drosophila heart. By stimulating the pacemaker with 472 nm pulsed laser light at different frequencies, we achieved non-invasive and more specific optical control of the Drosophila heart rhythm, which demonstrates the wide potential of optical pacing for studying cardiac dynamics and development. Imaging capability of our customized OCM system was also involved to observe the pacing effect visually. No tissue damage was found after long exposure to laser pulses, which proved the safety of optogenetic control of Drosophila heart.

  3. Optogenetic pacing in Drosophila models (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Wu, Penghe; Li, Airong; Men, Jing; Tans, Rudolph E.; Zhou, Chao

    2017-02-01

    The Drosophila melanogaster shares many similarities with vertebrates in heart development. Comparison of heart structural and functional characteristic between male and female Drosophila melanogaster at different developmental stages is helpful to understand heart morphogenesis and function for different genders. And also, it opens up the possibility to uncover the role of sex-related genes in heart development. In this longitudinal study, we cultured and tracked dozens of individually labeled flies throughout their lifecycle. The heart characteristic was measured at different developmental stages during culturing. The gender of each individual fly was determined by adult stage so that the collected data of early stages could be classified to male or female group. We adapted a high-speed optical coherence microscopy (OCM) system with axial and transverse resolution of 2um and 4um, respectively, to perform non-invasive M-mode imaging at a frame rate of 132Hz in Drosophila heart at third instar larva, early pupa and adult stage. Based on those GPU processed M-mode OCM images, we segmented the fly heart region and then quantified the cardiac structural and functional parameters such as heart rate, heart chamber size and so on. Despite large variances of wild type Drosophila in terms of some cardiac characteristic, our results suggest that the heart rate is lower for male flies than for female flies, especially at third instar larva stage. The end diastolic area (EDA) and end systolic area (ESA) of the heart are both slightly larger in female flies than in male flies at larva and adult stage. In summary, we showed gender differences of wild type drosophila in heart functional and structural characteristic.

  4. Sexual deprivation increases ethanol intake in Drosophila.

    PubMed

    Shohat-Ophir, G; Kaun, K R; Azanchi, R; Mohammed, H; Heberlein, U

    2012-03-16

    The brain's reward systems reinforce behaviors required for species survival, including sex, food consumption, and social interaction. Drugs of abuse co-opt these neural pathways, which can lead to addiction. Here, we used Drosophila melanogaster to investigate the relationship between natural and drug rewards. In males, mating increased, whereas sexual deprivation reduced, neuropeptide F (NPF) levels. Activation or inhibition of the NPF system in turn reduced or enhanced ethanol preference. These results thus link sexual experience, NPF system activity, and ethanol consumption. Artificial activation of NPF neurons was in itself rewarding and precluded the ability of ethanol to act as a reward. We propose that activity of the NPF-NPF receptor axis represents the state of the fly reward system and modifies behavior accordingly.

  5. Cocoa confers life span extension in Drosophila melanogaster.

    PubMed

    Bahadorani, Sepehr; Hilliker, Arthur J

    2008-06-01

    Cocoa is thought to be an excellent source of antioxidants. Here, we investigated the effects of cocoa supplementation on Drosophila melanogaster life span under different oxidative stress conditions. Our results illustrate that a moderate supplementation of cocoa under normoxia increases the average life span, whereas, at higher concentrations, average life span is normal. Under hyperoxia or in a Cu/Zn-superoxide dismutase-deficient background, cocoa exhibited a strong antioxidant activity, significantly increasing the average life span. Nevertheless, cocoa supplementation in a Mn-superoxide dismutase-deficient background enhanced an earlier mortality accompanied by a loss of climbing ability, indicating that cocoa may act as a pro-oxidant in mitochondria under conditions of extreme oxidative stress. Finally, we illustrate that cocoa also acts as a metal chelator in the presence of excess heavy metals, enhancing larval survival to the adult stage on copper or iron-supplemented medium. Taken together, our results document the antioxidative, pro-oxidative, and metal-chelating effects of cocoa on Drosophila melanogaster life span.

  6. We also CanFly! The 2nd MexFly drosophila research conference.

    PubMed

    Missirlis, Fanis; Nahmad, Marcos

    2017-04-03

    The 2nd Mexican Drosophila Research Conference (MexFly) took place on June 30th and July 1st, 2016 in Mexico City, at the Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav). Principal investigators, postdocs, students, and technicians from Drosophila labs across Mexico attended. The guest speaker was Chris Rushlow from New York University, who presented work on Zelda, a key transcriptional activator of the early zygotic genome. Here we provide a brief report of the meeting, which sketches the present landscape of Drosophila research in Mexico. We also provide a brief historical note on one of the pioneers of the field in this country, Victor Salceda, personally trained by Theodosius Dobzhansky. Salceda presented at the meeting an update of his collaborative project with Dobzhansky on the distribution of Drosophila pseudoobscura chromosomal inversions, initiated over forty years ago.

  7. Increased transsulfuration mediates longevity and dietary restriction in Drosophila.

    PubMed

    Kabil, Hadise; Kabil, Omer; Banerjee, Ruma; Harshman, Lawrence G; Pletcher, Scott D

    2011-10-04

    The mechanisms through which dietary restriction enhances health and longevity in diverse species are unclear. The transsulfuration pathway (TSP) is a highly conserved mechanism for metabolizing the sulfur-containing amino acids, methionine and cysteine. Here we show that Drosophila cystathionine β-synthase (dCBS), which catalyzes the rate-determining step in the TSP, is a positive regulator of lifespan in Drosophila and that the pathway is required for the effects of diet restriction on animal physiology and lifespan. dCBS activity was up-regulated in flies exposed to reduced nutrient conditions, and ubiquitous or neuron-specific transgenic overexpression of dCBS enhanced longevity in fully fed animals. Inhibition of the TSP abrogated the changes in lifespan, adiposity, and protein content that normally accompany diet restriction. RNAi-mediated knockdown of dCBS also limited lifespan extension by diet. Diet restriction reduced levels of protein translation in Drosophila, and we show that this is largely caused by increased metabolic commitment of methionine cycle intermediates to transsulfuration. However, dietary supplementation of methionine restored normal levels of protein synthesis to restricted animals without affecting lifespan, indicating that global reductions in translation alone are not required for diet-restriction longevity. Our results indicate a mechanism by which dietary restriction influences physiology and aging.

  8. Increased Sleep Promotes Survival during a Bacterial Infection in Drosophila

    PubMed Central

    Kuo, Tzu-Hsing; Williams, Julie A.

    2014-01-01

    Study Objectives: The relationship between sleep and immune function is not well understood at a functional or molecular level. We therefore used a genetic approach in Drosophila to manipulate sleep and evaluated effects on the ability of flies to fight bacterial infection. Setting: Laboratory. Participants: Drosophila melanogaster. Methods and Results: We used a genetic approach to transiently alter neuronal excitability in the mushroom body, a region in the central brain that is known to regulate sleep. Flies with increased sleep for up to two days prior to a bacterial infection showed increased resistance to the infection and improved survival. These flies also had increased expression levels of a subset of anti-microbial peptide mRNA prior to infection, as well as increased NFκB activity during infection as indicated by in vivo luciferase reporter activity. In contrast, flies that experienced reduced sleep for up to two days prior to infection had no effect on survival or on NFκB activity during infection. However, flies with reduced sleep showed an altered defense mechanism, such that resistance to infection was increased, but at the expense of reduced tolerance. This effect was dependent on environmental condition. Conclusions: Increasing sleep enhanced activity of an NFκB transcription factor, increased resistance to infection, and strongly promoted survival. Together, these findings support the hypothesis that sleep is beneficial to the host by maintaining a robust immune system. Citation: Kuo TH, Williams JA. Increased sleep promotes survival during a bacterial infection in Drosophila. SLEEP 2014;37(6):1077-1086. PMID:24882902

  9. Reducing canonical Wingless/Wnt signaling pathway confers protection against mutant Huntingtin toxicity in Drosophila.

    PubMed

    Dupont, Pascale; Besson, Marie-Thérèse; Devaux, Jérôme; Liévens, Jean-Charles

    2012-08-01

    Huntington's disease (HD) is a genetic neurodegenerative disease characterized by movement disorders, cognitive decline and neuropsychiatric symptoms. HD is caused by expanded CAG tract within the coding region of Huntingtin protein. Despite major insights into the molecular mechanisms leading to HD, no effective cure is yet available. Mutant Huntingtin (mHtt) has been reported to alter the stability and levels of β-Catenin, a key molecule in cell adhesion and signal transduction in Wingless (Wg)/Wnt pathway. However it remains to establish whether manipulation of Wg/Wnt signaling can impact HD pathology. We here investigated the phenotypic interactions between mHtt and Wg/Wnt signaling by using the power of Drosophila genetics. We provide compelling evidence that reducing Armadillo/β-Catenin levels confers protection and that this beneficial effect is correlated with the inactivation of the canonical Wg/Wnt signaling pathway. Knockdowns of Wnt ligands or of the downstream transcription factor Pangolin/TCF both ameliorate the survival of HD flies. Similarly, overexpression of one Armadillo/β-Catenin destruction complex component (Axin, APC2 or Shaggy/GSK-3β) increases the lifespan of HD flies. Loss of functional Armadillo/β-Catenin not only abolishes neuronal intrinsic but also glia-induced alterations in HD flies. Our findings highlight that restoring canonical Wg/Wnt signaling may be of therapeutic value.

  10. Excess dietary aluminum increases Drosophila's rate of aging.

    PubMed

    Massie, H R; Williams, T R; Aiello, V R

    1985-01-01

    Aluminum concentrations in the whole organism increased during development and aging of Drosophila melanogaster. The amount of aluminum in the flies was also reflected by the dietary content of aluminum. Additional dietary aluminum, in the form of aluminum salts, decreased the life span by as much as 20%. A significant reduction in life span was found for 1 X 10(-4) M aluminum chloride and for 1 X 10(-3) M aluminum nitrate and aluminum sulfate. Dietary sodium fluoride failed to increase life span.

  11. Increased sleep promotes survival during a bacterial infection in Drosophila.

    PubMed

    Kuo, Tzu-Hsing; Williams, Julie A

    2014-06-01

    The relationship between sleep and immune function is not well understood at a functional or molecular level. We therefore used a genetic approach in Drosophila to manipulate sleep and evaluated effects on the ability of flies to fight bacterial infection. Laboratory. Drosophila melanogaster. We used a genetic approach to transiently alter neuronal excitability in the mushroom body, a region in the central brain that is known to regulate sleep. Flies with increased sleep for up to two days prior to a bacterial infection showed increased resistance to the infection and improved survival. These flies also had increased expression levels of a subset of anti-microbial peptide mRNA prior to infection, as well as increased NFκB activity during infection as indicated by in vivo luciferase reporter activity. In contrast, flies that experienced reduced sleep for up to two days prior to infection had no effect on survival or on NFκB activity during infection. However, flies with reduced sleep showed an altered defense mechanism, such that resistance to infection was increased, but at the expense of reduced tolerance. This effect was dependent on environmental condition. Increasing sleep enhanced activity of an NFκB transcription factor, increased resistance to infection, and strongly promoted survival. Together, these findings support the hypothesis that sleep is beneficial to the host by maintaining a robust immune system.

  12. Increased volatile anesthetic requirement in short-sleeping Drosophila mutants

    PubMed Central

    Weber, Bernd; Schaper, Christian; Bushey, Daniel; Rohlfs, Marko; Steinfath, Markus; Tononi, Giulio; Cirelli, Chiara; Scholz, Jens; Bein, Berthold

    2009-01-01

    Background Anesthesia and sleep share physiological and behavioral similarities. The anesthetic requirement of the recently identified Drosophila mutant minisleeper and other Drosophila mutants was investigated. Methods Sleep and wakefulness were determined by measuring activity of individual wild-type and mutant flies. Based on the response of the flies at different concentrations of the volatile anesthetics isoflurane and sevoflurane, concentration-response curves were generated and EC50 values were calculated. Results The average amount of daily sleep in wild-type Drosophila (n=64) was 965 ±15 minutes and 1022 ± 29 in na[har38] p>0.05; n=32) (mean ± SEM, all p compared to wild-type and other shaker alleles). Shmns flies slept 584 ±13 minutes (n=64, p<0.01), Sh102 412 ± 22 minutes (n=32, p<0.01) and Sh120 782 ± 25 minutes (n=32, p<0.01). The EC50 values for isoflurane were 0.706 (95% confidence interval 0.649 to 0.764, n=661) and for sevoflurane 1.298 (1.180 to 1.416, n=522) in wild-type Drosophila, 1.599 (1.527 to 1.671, n=308) and 2.329 (2.177 to 2.482, n=282) in Sh102, 1.306 (1.212 to 1.400, n=393) and 2.013 (1.868 to 2.158, n=550) in Shmns, 0.957 (0.860 to 1.054, n=297) and 1.619 (1.508 to 1.731, n=386) in Sh120, and 0.6154 (0.581 to 0.649, n=360; p<0.05) and 0.9339 (0.823 to 1.041, n= 274) in na[har38], respectively (all p<0.01). Conclusions A single-gene mutation in Drosophila that causes an extreme reduction in daily sleep is responsible for a significant increase in the requirement of volatile anesthetics. This suggests that a single gene mutation affects both sleep behavior and anesthesia and sedation. PMID:19164958

  13. Hydrogen sulfide exposure increases desiccation tolerance in Drosophila melanogaster.

    PubMed

    Zhong, Jian-Feng; Wang, Shu-Ping; Shi, Xiao-Qin; Mu, Li-li; Li, Guo-Qing

    2010-12-01

    Hydrogen sulfide (H(2)S) has been shown to effect physiological alterations in several animals, frequently leading to an improvement in survival in otherwise lethal conditions. In the present paper, a volatility bioassay system was developed to evaluate the survivorship of Drosophila melanogaster adults exposed to H(2)S gas that emanated from a K(2)S donor. Using this bioassay system, we found that H(2)S exposure significantly increased the survival of flies under arid and food-free conditions, but not under humid and food-free conditions. This suggests that H(2)S plays a role in desiccation tolerance but not in nutritional stress alleviation. To further confirm the suggestion, the mRNA levels of two desiccation tolerance-related genes Frost and Desat2, and a starvation-related gene Smp-30, from the control and treated flies were measured by quantitative real-time PCR. These genes were up-regulated within 2h when the flies transferred to the arid and food-free bioassay system. Addition of H(2)S further increased Frost and Desat2 mRNA levels, in contrast to Smp-30. Thus, our molecular results were consistent with our bioassay findings. Because of the molecular and genetic tools available for Drosophila, the fly will be a useful system for determining how H(2)S regulates various physiological alterations. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Ethanol confers differential protection against generalist and specialist parasitoids of Drosophila melanogaster.

    PubMed

    Lynch, Zachary R; Schlenke, Todd A; Morran, Levi T; de Roode, Jacobus C

    2017-01-01

    As parasites coevolve with their hosts, they can evolve counter-defenses that render host immune responses ineffective. These counter-defenses are more likely to evolve in specialist parasites than generalist parasites; the latter face variable selection pressures between the different hosts they infect. Natural populations of the fruit fly Drosophila melanogaster are commonly threatened by endoparasitoid wasps in the genus Leptopilina, including the specialist L. boulardi and the generalist L. heterotoma, and both wasp species can incapacitate the cellular immune response of D. melanogaster larvae. Given that ethanol tolerance is high in D. melanogaster and stronger in the specialist wasp than the generalist, we tested whether fly larvae could use ethanol as an anti-parasite defense and whether its effectiveness would differ against the two wasp species. We found that fly larvae benefited from eating ethanol-containing food during exposure to L. heterotoma; we observed a two-fold decrease in parasitization intensity and a 24-fold increase in fly survival to adulthood. Although host ethanol consumption did not affect L. boulardi parasitization rates or intensities, it led to a modest increase in fly survival. Thus, ethanol conferred stronger protection against the generalist wasp than the specialist. We tested whether fly larvae can self-medicate by seeking ethanol-containing food after being attacked by wasps, but found no support for this hypothesis. We also allowed female flies to choose between control and ethanol-containing oviposition sites in the presence vs. absence of wasps and generally found significant preferences for ethanol regardless of wasp presence. Overall, our results suggest that D. melanogaster larvae obtain protection from certain parasitoid wasp species through their mothers' innate oviposition preferences for ethanol-containing food sources.

  15. Ethanol confers differential protection against generalist and specialist parasitoids of Drosophila melanogaster

    PubMed Central

    Schlenke, Todd A.; Morran, Levi T.; de Roode, Jacobus C.

    2017-01-01

    As parasites coevolve with their hosts, they can evolve counter-defenses that render host immune responses ineffective. These counter-defenses are more likely to evolve in specialist parasites than generalist parasites; the latter face variable selection pressures between the different hosts they infect. Natural populations of the fruit fly Drosophila melanogaster are commonly threatened by endoparasitoid wasps in the genus Leptopilina, including the specialist L. boulardi and the generalist L. heterotoma, and both wasp species can incapacitate the cellular immune response of D. melanogaster larvae. Given that ethanol tolerance is high in D. melanogaster and stronger in the specialist wasp than the generalist, we tested whether fly larvae could use ethanol as an anti-parasite defense and whether its effectiveness would differ against the two wasp species. We found that fly larvae benefited from eating ethanol-containing food during exposure to L. heterotoma; we observed a two-fold decrease in parasitization intensity and a 24-fold increase in fly survival to adulthood. Although host ethanol consumption did not affect L. boulardi parasitization rates or intensities, it led to a modest increase in fly survival. Thus, ethanol conferred stronger protection against the generalist wasp than the specialist. We tested whether fly larvae can self-medicate by seeking ethanol-containing food after being attacked by wasps, but found no support for this hypothesis. We also allowed female flies to choose between control and ethanol-containing oviposition sites in the presence vs. absence of wasps and generally found significant preferences for ethanol regardless of wasp presence. Overall, our results suggest that D. melanogaster larvae obtain protection from certain parasitoid wasp species through their mothers’ innate oviposition preferences for ethanol-containing food sources. PMID:28700600

  16. Epigenetic stability increases extensively during Drosophila follicle stem cell differentiation.

    PubMed

    Skora, Andrew D; Spradling, Allan C

    2010-04-20

    Stem and embryonic cells facilitate programming toward multiple daughter cell fates, whereas differentiated cells resist reprogramming and oncogenic transformation. How alterations in the chromatin-based machinery of epigenetic inheritance contribute to these differences remains poorly known. We observed random, heritable changes in GAL4/UAS transgene programming during Drosophila ovarian follicle stem cell differentiation and used them to measure the stage-specific epigenetic stability of gene programming. The frequency of GAL4/UAS reprogramming declines more than 100-fold over the nine divisions comprising this stem cell lineage. Stabilization acts in cis, suggesting that it is chromatin-based, and correlates with increased S phase length. Our results suggest that stem/early progenitor cells cannot accurately transmit nongenetic information to their progeny; full epigenetic competence is acquired only gradually during early differentiation. Modulating epigenetic inheritance may be a critical process controlling transitions between the pleuripotent and differentiated states.

  17. Nuclear hormone receptor DHR96 mediates the resistance to xenobiotics but not the increased lifespan of insulin-mutant Drosophila

    PubMed Central

    Afschar, Sonita; Toivonen, Janne M.; Tain, Luke Stephen; Wieser, Daniela; Finlayson, Andrew John; Driege, Yasmine; Alic, Nazif; Emran, Sahar; Stinn, Julia; Froehlich, Jenny; Piper, Matthew D.; Partridge, Linda

    2016-01-01

    Lifespan of laboratory animals can be increased by genetic, pharmacological, and dietary interventions. Increased expression of genes involved in xenobiotic metabolism, together with resistance to xenobiotics, are frequent correlates of lifespan extension in the nematode worm Caenorhabditis elegans, the fruit fly Drosophila, and mice. The Green Theory of Aging suggests that this association is causal, with the ability of cells to rid themselves of lipophilic toxins limiting normal lifespan. To test this idea, we experimentally increased resistance of Drosophila to the xenobiotic dichlordiphenyltrichlorethan (DDT), by artificial selection or by transgenic expression of a gene encoding a cytochrome P450. Although both interventions increased DDT resistance, neither increased lifespan. Furthermore, dietary restriction increased lifespan without increasing xenobiotic resistance, confirming that the two traits can be uncoupled. Reduced activity of the insulin/Igf signaling (IIS) pathway increases resistance to xenobiotics and extends lifespan in Drosophila, and can also increase longevity in C. elegans, mice, and possibly humans. We identified a nuclear hormone receptor, DHR96, as an essential mediator of the increased xenobiotic resistance of IIS mutant flies. However, the IIS mutants remained long-lived in the absence of DHR96 and the xenobiotic resistance that it conferred. Thus, in Drosophila IIS mutants, increased xenobiotic resistance and enhanced longevity are not causally connected. The frequent co-occurrence of the two traits may instead have evolved because, in nature, lowered IIS can signal the presence of pathogens. It will be important to determine whether enhanced xenobiotic metabolism is also a correlated, rather than a causal, trait in long-lived mice. PMID:26787908

  18. Nuclear hormone receptor DHR96 mediates the resistance to xenobiotics but not the increased lifespan of insulin-mutant Drosophila.

    PubMed

    Afschar, Sonita; Toivonen, Janne M; Hoffmann, Julia Marianne; Tain, Luke Stephen; Wieser, Daniela; Finlayson, Andrew John; Driege, Yasmine; Alic, Nazif; Emran, Sahar; Stinn, Julia; Froehlich, Jenny; Piper, Matthew D; Partridge, Linda

    2016-02-02

    Lifespan of laboratory animals can be increased by genetic, pharmacological, and dietary interventions. Increased expression of genes involved in xenobiotic metabolism, together with resistance to xenobiotics, are frequent correlates of lifespan extension in the nematode worm Caenorhabditis elegans, the fruit fly Drosophila, and mice. The Green Theory of Aging suggests that this association is causal, with the ability of cells to rid themselves of lipophilic toxins limiting normal lifespan. To test this idea, we experimentally increased resistance of Drosophila to the xenobiotic dichlordiphenyltrichlorethan (DDT), by artificial selection or by transgenic expression of a gene encoding a cytochrome P450. Although both interventions increased DDT resistance, neither increased lifespan. Furthermore, dietary restriction increased lifespan without increasing xenobiotic resistance, confirming that the two traits can be uncoupled. Reduced activity of the insulin/Igf signaling (IIS) pathway increases resistance to xenobiotics and extends lifespan in Drosophila, and can also increase longevity in C. elegans, mice, and possibly humans. We identified a nuclear hormone receptor, DHR96, as an essential mediator of the increased xenobiotic resistance of IIS mutant flies. However, the IIS mutants remained long-lived in the absence of DHR96 and the xenobiotic resistance that it conferred. Thus, in Drosophila IIS mutants, increased xenobiotic resistance and enhanced longevity are not causally connected. The frequent co-occurrence of the two traits may instead have evolved because, in nature, lowered IIS can signal the presence of pathogens. It will be important to determine whether enhanced xenobiotic metabolism is also a correlated, rather than a causal, trait in long-lived mice.

  19. A Low Protein Diet Increases the Hypoxic Tolerance in Drosophila

    PubMed Central

    Vigne, Paul; Frelin, Christian

    2006-01-01

    Dietary restriction is well known to increase the life span of a variety of organisms from yeast to mammals, but the relationships between nutrition and the hypoxic tolerance have not yet been considered. Hypoxia is a major cause of cell death in myocardial infarction and stroke. Here we forced hypoxia-related death by exposing one-day-old male Drosophila to chronic hypoxia (5% O2) and analysed their survival. Chronic hypoxia reduced the average life span from 33.6 days to 6.3 days when flies were fed on a rich diet. A demographic analysis indicated that chronic hypoxia increased the slope of the mortality trajectory and not the short-term risk of death. Dietary restriction produced by food dilution, by yeast restriction, or by amino acid restriction partially reversed the deleterious action of hypoxia. It increased the life span of hypoxic flies up to seven days, which represented about 25% of the life time of an hypoxic fly. Maximum survival of hypoxic flies required only dietary sucrose, and it was insensitive to drugs such as rapamycin and resveratrol, which increase longevity of normoxic animals. The results thus uncover a new link between protein nutrition, nutrient signalling, and resistance to hypoxic stresses. PMID:17183686

  20. A low protein diet increases the hypoxic tolerance in Drosophila.

    PubMed

    Vigne, Paul; Frelin, Christian

    2006-12-20

    Dietary restriction is well known to increase the life span of a variety of organisms from yeast to mammals, but the relationships between nutrition and the hypoxic tolerance have not yet been considered. Hypoxia is a major cause of cell death in myocardial infarction and stroke. Here we forced hypoxia-related death by exposing one-day-old male Drosophila to chronic hypoxia (5% O(2)) and analysed their survival. Chronic hypoxia reduced the average life span from 33.6 days to 6.3 days when flies were fed on a rich diet. A demographic analysis indicated that chronic hypoxia increased the slope of the mortality trajectory and not the short-term risk of death. Dietary restriction produced by food dilution, by yeast restriction, or by amino acid restriction partially reversed the deleterious action of hypoxia. It increased the life span of hypoxic flies up to seven days, which represented about 25% of the life time of an hypoxic fly. Maximum survival of hypoxic flies required only dietary sucrose, and it was insensitive to drugs such as rapamycin and resveratrol, which increase longevity of normoxic animals. The results thus uncover a new link between protein nutrition, nutrient signalling, and resistance to hypoxic stresses.

  1. Human Cryptochrome-1 Confers Light Independent Biological Activity in Transgenic Drosophila Correlated with Flavin Radical Stability

    PubMed Central

    Vieira, Jacqueline; Jones, Alex R.; Danon, Antoine; Sakuma, Michiyo; Hoang, Nathalie; Robles, David; Tait, Shirley; Heyes, Derren J.; Picot, Marie; Yoshii, Taishi; Helfrich-Förster, Charlotte; Soubigou, Guillaume; Coppee, Jean-Yves; Klarsfeld, André; Rouyer, Francois; Scrutton, Nigel S.; Ahmad, Margaret

    2012-01-01

    Cryptochromes are conserved flavoprotein receptors found throughout the biological kingdom with diversified roles in plant development and entrainment of the circadian clock in animals. Light perception is proposed to occur through flavin radical formation that correlates with biological activity in vivo in both plants and Drosophila. By contrast, mammalian (Type II) cryptochromes regulate the circadian clock independently of light, raising the fundamental question of whether mammalian cryptochromes have evolved entirely distinct signaling mechanisms. Here we show by developmental and transcriptome analysis that Homo sapiens cryptochrome - 1 (HsCRY1) confers biological activity in transgenic expressing Drosophila in darkness, that can in some cases be further stimulated by light. In contrast to all other cryptochromes, purified recombinant HsCRY1 protein was stably isolated in the anionic radical flavin state, containing only a small proportion of oxidized flavin which could be reduced by illumination. We conclude that animal Type I and Type II cryptochromes may both have signaling mechanisms involving formation of a flavin radical signaling state, and that light independent activity of Type II cryptochromes is a consequence of dark accumulation of this redox form in vivo rather than of a fundamental difference in signaling mechanism. PMID:22427812

  2. In vivo photoacoustic neuronal imaging of odor-evoked calcium signals in the drosophila brain (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Zhang, Ruiying; Rao, Bin; Rong, Haoyang; Raman, Baranidharan; Wang, Lihong V.

    2016-03-01

    Neural scientists can benefit greatly from imaging tools that can penetrate thick brain tissue. Compared with traditional optical microscopy methods, photoacoustic imaging can beat the optical diffusion limit and achieve such deep tissue imaging with high spatial resolution. In this study, we used an optical-resolution photoacoustic microscope to image the odor-evoked neuronal activities in a drosophila model. Drosophila brain neurons stably express GCaMP5G, a calcium-sensitive fluorescent protein whose optical absorption coefficient changes with calcium influx during action potentials. We recorded an ~20% odor-evoked fractional photoacoustic signal increase at all depths of the drosophila brain in vivo, with and without removal of the brain cuticle, at a recording rate of 1 kHz. Our results were confirmed by concurrent fluorescent recordings. Furthermore, by performing fast 2D scanning, we imaged the antenna lobe region, which is of particular interest in neuroscience, at a volumetric rate of ~1 Hz with a sub-neuron resolution of 3 μm. Unlike optical imaging, which requires surgical removal of the scattering brain cuticle, our photoacoustic system can image through the cuticle and measure neuronal signals of the whole drosophila brain without invasive surgery, enabling minimal disturbance to the animal's behaviors. In conclusion, we have demonstrated photoacoustic imaging of calcium signals in drosophila brains for the first time. Utilizing the deep imaging capability of photoacoustic tomography, our methods could potentially be extended to in vivo imaging of neuronal activities from deep brains in other animal models.

  3. Increased centrosome amplification in aged stem cells of the Drosophila midgut

    SciTech Connect

    Park, Joung-Sun; Pyo, Jung-Hoon; Na, Hyun-Jin; Jeon, Ho-Jun; Kim, Young-Shin; Arking, Robert; Yoo, Mi-Ae

    2014-07-25

    Highlights: • Increased centrosome amplification in ISCs of aged Drosophila midguts. • Increased centrosome amplification in ISCs of oxidative stressed Drosophila midguts. • Increased centrosome amplification in ISCs by overexpression of PVR, EGFR, and AKT. • Supernumerary centrosomes can be responsible for abnormal ISC polyploid cells. • Supernumerary centrosomes can be a useful marker for aging stem cells. - Abstract: Age-related changes in long-lived tissue-resident stem cells may be tightly linked to aging and age-related diseases such as cancer. Centrosomes play key roles in cell proliferation, differentiation and migration. Supernumerary centrosomes are known to be an early event in tumorigenesis and senescence. However, the age-related changes of centrosome duplication in tissue-resident stem cells in vivo remain unknown. Here, using anti-γ-tubulin and anti-PH3, we analyzed mitotic intestinal stem cells with supernumerary centrosomes in the adult Drosophila midgut, which may be a versatile model system for stem cell biology. The results showed increased centrosome amplification in intestinal stem cells of aged and oxidatively stressed Drosophila midguts. Increased centrosome amplification was detected by overexpression of PVR, EGFR, and AKT in intestinal stem cells/enteroblasts, known to mimic age-related changes including hyperproliferation of intestinal stem cells and hyperplasia in the midgut. Our data show the first direct evidence for the age-related increase of centrosome amplification in intestinal stem cells and suggest that the Drosophila midgut is an excellent model for studying molecular mechanisms underlying centrosome amplification in aging adult stem cells in vivo.

  4. Mutations of acetylcholinesterase which confer insecticide resistance in Drosophila melanogaster populations

    PubMed Central

    Menozzi, Philippe; Shi, Ming An; Lougarre, Andrée; Tang, Zhen Hua; Fournier, Didier

    2004-01-01

    Background Organophosphate and carbamate insecticides irreversibly inhibit acetylcholinesterase causing death of insects. Resistance-modified acetylcholinesterases(AChEs) have been described in many insect species and sequencing of their genes allowed several point mutations to be described. However, their relative frequency and their cartography had not yet been addressed. Results To analyze the most frequent mutations providing insecticide resistance in Drosophila melanogaster acetylcholinesterase, the Ace gene was cloned and sequenced in several strains harvested from different parts of the world. Sequence comparison revealed four widespread mutations, I161V, G265A, F330Y and G368A. We confirm here that mutations are found either isolated or in combination in the same protein and we show that most natural populations are heterogeneous, composed of a mixture of different alleles. In vitro expression of mutated proteins showed that combining mutations in the same protein has two consequences: it increases resistance level and provides a wide spectrum of resistance. Conclusion The presence of several alleles in natural populations, offering various resistance to carbamate and organophosphate compounds will complicate the establishment of resistance management programs. PMID:15018651

  5. Mutations in Dalpha1 or Dbeta2 nicotinic acetylcholine receptor subunits can confer resistance to neonicotinoids in Drosophila melanogaster.

    PubMed

    Perry, Trent; Heckel, David G; McKenzie, John A; Batterham, Philip

    2008-05-01

    Resistance to insecticides by modification of their molecular targets is a serious problem in chemical control of many arthropod pests. Neonicotinoids target the nicotinic acetylcholine receptor (nAChR) of arthropods. The spectrum of possible resistance-conferring mutations of this receptor is poorly understood. Prediction of resistance is complicated by the existence of multiple genes encoding the different subunits of this essential component of neurotransmission. We focused on the cluster of three Drosophila melanogaster nAChR subunit genes at cytological region 96A. EMS mutagenesis and selection for resistance to nitenpyram was performed on hybrids carrying a deficiency for this chromosomal region. Two complementation groups were defined for the four strains isolated. Molecular characterisation of the mutations found lesions in two nAChR subunit genes, Dalpha1 (encoding an alpha-type subunit) and Dbeta2 (beta-type). Mutations conferring resistance in beta-type receptors have not previously been reported, but we found several lesions in the Dbeta2 sequence, including locations distant from the predicted neonicotinoid-binding site. This study illustrates that mutations in a single-receptor subunit can confer nitenpyram resistance. Moreover, some of the mutations may protect the insect against nitenpyram by interfering with subunit assembly or channel activation, rather than affecting binding affinities of neonicotinoids to the channel.

  6. Genetic Changes to a Transcriptional Silencer Element Confers Phenotypic Diversity within and between Drosophila Species

    PubMed Central

    Watada, Masayoshi; Pruitt, Jonathan N.; Williams, Thomas M.; Rebeiz, Mark

    2015-01-01

    The modification of transcriptional regulation has become increasingly appreciated as a major contributor to morphological evolution. However, the role of negative-acting control elements (e.g. silencers) in generating morphological diversity has been generally overlooked relative to positive-acting “enhancer” elements. The highly variable body coloration patterns among Drosophilid insects represents a powerful model system in which the molecular alterations that underlie phenotypic diversity can be defined. In a survey of pigment phenotypes among geographically disparate Japanese populations of Drosophila auraria, we discovered a remarkable degree of variation in male-specific abdominal coloration. In testing the expression patterns of the major pigment-producing enzymes, we found that phenotypes uniquely correlated with differences in the expression of ebony, a gene required for yellow-colored cuticle. Assays of ebony’s transcriptional control region indicated that a lightly pigmented strain harbored cis-regulatory mutations that caused correlated changes in its expression. Through a series of chimeric reporter constructs between light and dark strain alleles, we localized function-altering mutations to a conserved silencer that mediates a male-specific pattern of ebony repression. This suggests that the light allele was derived through the loss of this silencer’s activity. Furthermore, examination of the ebony gene of D. serrata, a close relative of D. auraria which secondarily lost male-specific pigmentation revealed the parallel loss of this silencer element. These results demonstrate how loss-of-function mutations in a silencer element resulted in increased gene expression. We propose that the mutational inactivation of silencer elements may represent a favored path to evolve gene expression, impacting morphological traits. PMID:26115430

  7. Genetic Changes to a Transcriptional Silencer Element Confers Phenotypic Diversity within and between Drosophila Species.

    PubMed

    Johnson, Winslow C; Ordway, Alison J; Watada, Masayoshi; Pruitt, Jonathan N; Williams, Thomas M; Rebeiz, Mark

    2015-06-01

    The modification of transcriptional regulation has become increasingly appreciated as a major contributor to morphological evolution. However, the role of negative-acting control elements (e.g. silencers) in generating morphological diversity has been generally overlooked relative to positive-acting "enhancer" elements. The highly variable body coloration patterns among Drosophilid insects represents a powerful model system in which the molecular alterations that underlie phenotypic diversity can be defined. In a survey of pigment phenotypes among geographically disparate Japanese populations of Drosophila auraria, we discovered a remarkable degree of variation in male-specific abdominal coloration. In testing the expression patterns of the major pigment-producing enzymes, we found that phenotypes uniquely correlated with differences in the expression of ebony, a gene required for yellow-colored cuticle. Assays of ebony's transcriptional control region indicated that a lightly pigmented strain harbored cis-regulatory mutations that caused correlated changes in its expression. Through a series of chimeric reporter constructs between light and dark strain alleles, we localized function-altering mutations to a conserved silencer that mediates a male-specific pattern of ebony repression. This suggests that the light allele was derived through the loss of this silencer's activity. Furthermore, examination of the ebony gene of D. serrata, a close relative of D. auraria which secondarily lost male-specific pigmentation revealed the parallel loss of this silencer element. These results demonstrate how loss-of-function mutations in a silencer element resulted in increased gene expression. We propose that the mutational inactivation of silencer elements may represent a favored path to evolve gene expression, impacting morphological traits.

  8. Vitellogenin family gene expression does not increase Drosophila lifespan or fecundity

    PubMed Central

    Ren, Yingxue; Hughes, Kimberly A.

    2014-01-01

    One of the most striking patterns in comparative biology is the negative correlation between lifespan and fecundity observed in comparisons among species. This pattern is consistent with the idea that organisms need to allocate a fixed energy budget among competing demands of growth, development, reproduction and somatic maintenance. However, exceptions to this pattern have been observed in many social insects, including ants, bees, and termites.  In honey bees ( Apis mellifera), Vitellogenin ( Vg), a yolk protein precursor, has been implicated in mediating the long lifespan and high fecundity of queen bees. To determine if Vg-like proteins can regulate lifespan in insects generally, we examined the effects of expression of Apis Vg and Drosophila CG31150 (a Vg-like gene recently identified as cv-d) on Drosophila melanogaster lifespan and fecundity using the RU486-inducible GeneSwitch system. For all genotypes tested, overexpression of Vg and CG31150 decreased Drosophila lifespan and did not affect total or age-specific fecundity. We also detected an apparent effect of the GeneSwitch system itself, wherein RU486 exposure (or the GAL4 expression it induces) led to a significant increase in longevity and decrease in fecundity in our fly strains. This result is consistent with the pattern reported in a recent meta-analysis of Drosophila aging studies, where transgenic constructs of the UAS/GAL4 expression system that should have no effect (e.g. an uninduced GeneSwitch) significantly extended lifespan in some genetic backgrounds. Our results suggest that Vg-family genes are not major regulators of Drosophila life history traits, and highlight the importance of using appropriate controls in aging studies. PMID:25110583

  9. Expression of a Drosophila glutathione transferase in Arabidopsis confers the ability to detoxify the environmental pollutant, and explosive, 2,4,6-trinitrotoluene.

    PubMed

    Tzafestas, Kyriakos; Razalan, Maria M; Gyulev, Ivan; Mazari, Aslam M A; Mannervik, Bengt; Rylott, Elizabeth L; Bruce, Neil C

    2017-04-01

    The explosive 2,4,6-trinitrotoluene (TNT) is a significant, global environmental pollutant that is both toxic and recalcitrant to degradation. Given the sheer scale and inaccessible nature of contaminated areas, phytoremediation may be a viable clean-up approach. Here, we have characterized a Drosophila melanogaster glutathione transferase (DmGSTE6) which has activity towards TNT. Recombinantly expressed, purified DmGSTE6 produces predominantly 2-glutathionyl-4,6-dinitrotoluene, and has a 2.5-fold higher Maximal Velocity (Vmax ), and five-fold lower Michaelis Constant (Km ) than previously characterized TNT-active Arabidopsis thaliana (Arabidopsis) GSTs. Expression of DmGSTE6 in Arabidopsis conferred enhanced resistance to TNT, and increased the ability to remove TNT from contaminated soil relative to wild-type plants. Arabidopsis lines overexpressing TNT-active GSTs AtGST-U24 and AtGST-U25 were compromised in biomass production when grown in the absence of TNT. This yield drag was not observed in the DmGSTE6-expressing Arabidopsis lines. We hypothesize that increased levels of endogenous TNT-active GSTs catalyse excessive glutathionylation of endogenous substrates, depleting glutathione pools, an activity that DmGST may lack. In conclusion, DmGSTE6 has activity towards TNT, producing a compound with potential for further biodegradation. Selecting or manipulating plants to confer DmGSTE6-like activity could contribute towards development of phytoremediation strategies to clean up TNT from polluted military sites.

  10. Drosophila Longevity Assurance Conferred by Reduced Insulin Receptor Substrate Chico Partially Requires d4eBP.

    PubMed

    Bai, Hua; Post, Stephanie; Kang, Ping; Tatar, Marc

    2015-01-01

    Mutations of the insulin/IGF signaling (IIS) pathway extend Drosophila lifespan. Based on genetic epistasis analyses, this longevity assurance is attributed to downstream effects of the FOXO transcription factor. However, as reported FOXO accounts for only a portion of the observed longevity benefit, suggesting there are additional outputs of IIS to mediate aging. One candidate is target of rapamycin complex 1 (TORC1). Reduced TORC1 activity is reported to slow aging, whereas reduced IIS is reported to repress TORC1 activity. The eukaryotic translation initiation factor 4E binding protein (4E-BP) is repressed by TORC1, and activated 4E-BP is reported to increase Drosophila lifespan. Here we use genetic epistasis analyses to test whether longevity assurance mutants of chico, the Drosophila insulin receptor substrate homolog, require Drosophila d4eBP to slow aging. In chico heterozygotes, which are robustly long-lived, d4eBP is required but not sufficient to slow aging. Remarkably, d4eBP is not required or sufficient for chico homozygotes to extend longevity. Likewise, chico heterozygote females partially require d4eBP to preserve age-dependent locomotion, and both chico genotypes require d4eBP to improve stress-resistance. Reproduction and most measures of growth affected by either chico genotype are always independent of d4eBP. In females, chico heterozygotes paradoxically produce more rather than less phosphorylated 4E-BP (p4E-BP). Altered IRS function within the IIS pathway of Drosophila appears to have partial, conditional capacity to regulate aging through an unconventional interaction with 4E-BP.

  11. Drosophila Longevity Assurance Conferred by Reduced Insulin Receptor Substrate Chico Partially Requires d4eBP

    PubMed Central

    Bai, Hua; Post, Stephanie; Kang, Ping; Tatar, Marc

    2015-01-01

    Mutations of the insulin/IGF signaling (IIS) pathway extend Drosophila lifespan. Based on genetic epistasis analyses, this longevity assurance is attributed to downstream effects of the FOXO transcription factor. However, as reported FOXO accounts for only a portion of the observed longevity benefit, suggesting there are additional outputs of IIS to mediate aging. One candidate is target of rapamycin complex 1 (TORC1). Reduced TORC1 activity is reported to slow aging, whereas reduced IIS is reported to repress TORC1 activity. The eukaryotic translation initiation factor 4E binding protein (4E-BP) is repressed by TORC1, and activated 4E-BP is reported to increase Drosophila lifespan. Here we use genetic epistasis analyses to test whether longevity assurance mutants of chico, the Drosophila insulin receptor substrate homolog, require Drosophila d4eBP to slow aging. In chico heterozygotes, which are robustly long-lived, d4eBP is required but not sufficient to slow aging. Remarkably, d4eBP is not required or sufficient for chico homozygotes to extend longevity. Likewise, chico heterozygote females partially require d4eBP to preserve age-dependent locomotion, and both chico genotypes require d4eBP to improve stress-resistance. Reproduction and most measures of growth affected by either chico genotype are always independent of d4eBP. In females, chico heterozygotes paradoxically produce more rather than less phosphorylated 4E-BP (p4E-BP). Altered IRS function within the IIS pathway of Drosophila appears to have partial, conditional capacity to regulate aging through an unconventional interaction with 4E-BP. PMID:26252766

  12. The Smc5/Smc6/MAGE complex confers resistance to caffeine and genotoxic stress in Drosophila melanogaster.

    PubMed

    Li, Xiao; Zhuo, Ran; Tiong, Stanley; Di Cara, Francesca; King-Jones, Kirst; Hughes, Sarah C; Campbell, Shelagh D; Wevrick, Rachel

    2013-01-01

    The SMC5/6 protein complex consists of the Smc5, Smc6 and Non-Smc-Element (Nse) proteins and is important for genome stability in many species. To identify novel components in the DNA repair pathway, we carried out a genetic screen to identify mutations that confer reduced resistance to the genotoxic effects of caffeine, which inhibits the ATM and ATR DNA damage response proteins. This approach identified inactivating mutations in CG5524 and MAGE, homologs of genes encoding Smc6 and Nse3 in yeasts. The fact that Smc5 mutants are also caffeine-sensitive and that Mage physically interacts with Drosophila homologs of Nse proteins suggests that the structure of the Smc5/6 complex is conserved in Drosophila. Although Smc5/6 proteins are required for viability in S. cerevisiae, they are not essential under normal circumstances in Drosophila. However, flies carrying mutations in Smc5, Smc6 and MAGE are hypersensitive to genotoxic agents such as ionizing radiation, camptothecin, hydroxyurea and MMS, consistent with the Smc5/6 complex serving a conserved role in genome stability. We also show that mutant flies are not compromised for pre-mitotic cell cycle checkpoint responses. Rather, caffeine-induced apoptosis in these mutants is exacerbated by inhibition of ATM or ATR checkpoint kinases but suppressed by Rad51 depletion, suggesting a functional interaction involving homologous DNA repair pathways that deserves further scrutiny. Our insights into the SMC5/6 complex provide new challenges for understanding the role of this enigmatic chromatin factor in multi-cellular organisms.

  13. The Smc5/Smc6/MAGE Complex Confers Resistance to Caffeine and Genotoxic Stress in Drosophila melanogaster

    PubMed Central

    Li, Xiao; Zhuo, Ran; Tiong, Stanley; Di Cara, Francesca; King-Jones, Kirst; Hughes, Sarah C.; Campbell, Shelagh D.; Wevrick, Rachel

    2013-01-01

    The SMC5/6 protein complex consists of the Smc5, Smc6 and Non-Smc-Element (Nse) proteins and is important for genome stability in many species. To identify novel components in the DNA repair pathway, we carried out a genetic screen to identify mutations that confer reduced resistance to the genotoxic effects of caffeine, which inhibits the ATM and ATR DNA damage response proteins. This approach identified inactivating mutations in CG5524 and MAGE, homologs of genes encoding Smc6 and Nse3 in yeasts. The fact that Smc5 mutants are also caffeine-sensitive and that Mage physically interacts with Drosophila homologs of Nse proteins suggests that the structure of the Smc5/6 complex is conserved in Drosophila. Although Smc5/6 proteins are required for viability in S. cerevisiae, they are not essential under normal circumstances in Drosophila. However, flies carrying mutations in Smc5, Smc6 and MAGE are hypersensitive to genotoxic agents such as ionizing radiation, camptothecin, hydroxyurea and MMS, consistent with the Smc5/6 complex serving a conserved role in genome stability. We also show that mutant flies are not compromised for pre-mitotic cell cycle checkpoint responses. Rather, caffeine-induced apoptosis in these mutants is exacerbated by inhibition of ATM or ATR checkpoint kinases but suppressed by Rad51 depletion, suggesting a functional interaction involving homologous DNA repair pathways that deserves further scrutiny. Our insights into the SMC5/6 complex provide new challenges for understanding the role of this enigmatic chromatin factor in multi-cellular organisms. PMID:23555814

  14. Edible bird's nest enhances antioxidant capacity and increases lifespan in Drosophila Melanogaster.

    PubMed

    Hu, Q; Li, G; Yao, H; He, S; Li, H; Liu, S; Wu, Y; Lai, X

    2016-04-30

    In this study, we aims to investigate the effects of edible bird's nest (EBN) on anti-aging efficacy. In order to investigate lifespan and mortality rate of flies, we treated flies with various doses of EBN. Besides, fecundity, water content and food are determined and heat-stress test is conducted after flies treating with different medium. Effects of EBN on total antioxidant activity (T-AOC), super-oxide dismutase activity (SOD), catalase activity (CAT), and malondialdehyde (MDA) were examined in drosophila melanogaster. Results indicated that flies in EBN treated group illustrated significantly lower mortality rates and longer median and maximum lifespan compared to control group (P<0.05). The fecundity in EBN-treated group was increased compared to control group. SOD levels and CAT activity were significantly increased, and MDA levels decreased in EBN-treated group compared to control group (P<0.01). In conclusion, EBN can extend lifespan, decrease mortality rate and increase survival rate in heat-stress test, and which can also promote SOD and CAT activity and reduce MDA levels. EBN is able to delay drosophila melanogaster aging, attributing to the increasing antioxidant enzyme activities and decreasing content of lipid peroxidation products in drosophila melanogaster.

  15. Lack of increase in DNA crosslinking in Drosophila melanogaster with age.

    PubMed

    Massie, H R; Baird, M B; Williams, T R

    1975-01-01

    Adult Drosophila melanogaster fruit flies ranging in age from 2 to 7.5 weeks with a median colony survival time of 6.4 weeks at 25 degrees C showed no increase in DNA crosslinking with age. The purified denatured DNA used for crosslink determinations varied in molecular weight from 2.02 to 3.84 times 10(5) daltons and was crosslinked to the extent of 6.2-8.8% with no age-related trend.

  16. Evolution of increased larval competitive ability in Drosophila melanogaster without increased larval feeding rate.

    PubMed

    Sarangi, Manaswini; Nagarajan, Archana; Dey, Snigdhadip; Bose, Joy; Joshi, Amitabh

    2016-09-01

    Multiple experimental evolution studies on Drosophila melanogaster in the 1980s and 1990s indicated that enhanced competitive ability evolved primarily through increased larval tolerance to nitrogenous wastes and increased larval feeding and foraging rate, at the cost of efficiency of food conversion to biomass, and this became the widely accepted view of how adaptation to larval crowding evolves in fruitflies.We recently showed that populations of D. ananassae and D. n. nasuta subjected to extreme larval crowding evolved greater competitive ability without evolving higher feeding rates, primarily through a combination of reduced larval duration, faster attainment of minimum critical size for pupation, greater efficiency of food conversion to biomass, increased pupation height and, perhaps, greater urea/ammonia tolerance. This was a very different suite of traits than that seen to evolve under similar selection in D. melanogaster and was closer to the expectations from the theory of K-selection. At that time, we suggested two possible reasons for the differences in the phenotypic correlates of greater competitive ability seen in the studies with D. melanogaster and the other two species. First, that D. ananassae and D. n. nasuta had a very different genetic architecture of traits affecting competitive ability compared to the long-term laboratory populations of D. melanogaster used in the earlier studies, either because the populations of the former two species were relatively recently wild-caught, or by virtue of being different species. Second, that the different evolutionary trajectories in D. ananassae and D. n. nasuta versus D. melanogaster were a reflection of differences in the manner in which larval crowding was imposed in the two sets of selection experiments. The D. melanogaster studies used a higher absolute density of eggs per unit volume of food, and a substantially larger total volume of food, than the studies on D. ananassae and D. n. nasuta. Here, we

  17. Dietary intake of Curcuma longa and Emblica officinalis increases life span in Drosophila melanogaster.

    PubMed

    Rawal, Shilpa; Singh, Pavneet; Gupta, Ayush; Mohanty, Sujata

    2014-01-01

    Intake of food and nutrition plays a major role in affecting aging process and longevity. However, the precise mechanisms underlying the ageing process are still unclear. To this respect, diet has been considered to be a determinant of ageing process. In order to better illustrate this, we used Drosophila melanogaster as a model and fed them orally with different concentrations of two commonly used Indian medicinal plant products, Curcuma longa (rhizome) and Emblica officinalis (fruit). The results revealed significant increase in life span of Drosophila flies on exposure to both the plant products, more efficiently by C. Longa than by E. officinalis. In order to understand whether the increase in lifespan was due to high-antioxidant properties of these medicinal plants, we performed enzymatic assays to assess the SOD and catalase activities in case of both treated and control Drosophila flies. Interestingly, the results support the free radical theory of aging as both these plant derivatives show high reactive oxygen species (ROS) scavenging activities.

  18. Cardiac optogenetic pacing in drosophila melanogaster using red-shifted opsins (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Men, Jing; Li, Airong; Jerwick, Jason; Tanzi, Rudolph E.; Zhou, Chao

    2017-02-01

    Electrical pacing is the current gold standard for investigation of mammalian cardiac electrical conduction systems as well as for treatment of certain cardiac pathologies. However, this method requires an invasive surgical procedure to implant the pacing electrodes. Recently, optogenetic pacing has been developed as an alternative, non-invasive method for heartbeat pacing in animals. It induces heartbeats by shining pulsed light on transgene-generated microbial opsins which in turn activate light gated ion channels in animal hearts. However, commonly used opsins, such as channelrhodopsin-2 (ChR2), require short light wavelength stimulation (475 nm), which is strongly absorbed and scattered by tissue. Here, we expressed recently engineered red-shifted opsins, ReaChR and CsChrimson, in the heart of a well-developed animal model, Drosophila melanogaster, for the first time. Optogenetic pacing was successfully conducted in both ReaChR and CsChrimson flies at their larval, pupal, and adult stages using 617 nm excitation light pulse, enabling a much deeper tissue penetration compared to blue stimulation light. A customized high speed and ultrahigh resolution OCM system was used to non-invasively monitor the heartbeat pacing in Drosophila. Compared to previous studies on optogenetic pacing of Drosophila, higher penetration depth of optogenetic excitation light was achieved in opaque late pupal flies. Lower stimulating power density is needed for excitation at each developmental stage of both groups, which improves the safety of this technique for heart rhythm studies.

  19. Human BMP sequences can confer normal dorsal-ventral patterning in the Drosophila embryo.

    PubMed

    Padgett, R W; Wozney, J M; Gelbart, W M

    1993-04-01

    The type beta transforming growth factor family is composed of a series of processed, secreted growth factors, several of which have been implicated in important regulatory roles in cell determination, inductive interactions, and tissue differentiation. Among these factors, the sequence of the DPP protein from Drosophila is most similar to two of the vertebrate bone morphogenetic proteins, BMP2 and BMP4. Here we report that the human BMP4 ligand sequences can function in lieu of DPP in Drosophila embryos. We introduced the ligand region from human BMP4 into a genomic fragment of the dpp gene in place of the Drosophila ligand sequences and recovered transgenic flies by P-element transformation. We find that this chimeric dpp-BMP4 transgene can completely rescue the embryonic dorsal-ventral patterning defect of null dpp mutant genotypes. We infer that the chimeric DPP-BMP4 protein can be processed properly and, by analogy with the action of other family members, can activate the endogenous DPP receptor to carry out the events necessary for dorsal-ventral patterning. Our evidence suggests that the DPP-BMP4 signal transduction pathway has been functionally conserved for at least 600 million years.

  20. Acidic Food pH Increases Palatability and Consumption and Extends Drosophila Lifespan12

    PubMed Central

    Deshpande, Sonali A; Yamada, Ryuichi; Mak, Christine M; Hunter, Brooke; Obando, Alina Soto; Hoxha, Sany; Ja, William W

    2015-01-01

    Background: Despite the prevalent use of Drosophila as a model in studies of nutrition, the effects of fundamental food properties, such as pH, on animal health and behavior are not well known. Objectives: We examined the effect of food pH on adult Drosophila lifespan, feeding behavior, and microbiota composition and tested the hypothesis that pH-mediated changes in palatability and total consumption are required for modulating longevity. Methods: We measured the effect of buffered food (pH 5, 7, or 9) on male gustatory responses (proboscis extension), total food intake, and male and female lifespan. The effect of food pH on germfree male lifespan was also assessed. Changes in fly-associated microbial composition as a result of food pH were determined by 16S ribosomal RNA gene sequencing. Male gustatory responses, total consumption, and male and female longevity were additionally measured in the taste-defective Pox neuro (Poxn) mutant and its transgenic rescue control. Results: An acidic diet increased Drosophila gustatory responses (40–230%) and food intake (5–50%) and extended survival (10–160% longer median lifespan) compared with flies on either neutral or alkaline pH food. Alkaline food pH shifted the composition of fly-associated bacteria and resulted in greater lifespan extension (260% longer median survival) after microbes were eliminated compared with flies on an acidic (50%) or neutral (130%) diet. However, germfree flies lived longer on an acidic diet (5–20% longer median lifespan) compared with those on either neutral or alkaline pH food. Gustatory responses, total consumption, and longevity were unaffected by food pH in Poxn mutant flies. Conclusions: Food pH can directly influence palatability and feeding behavior and affect parameters such as microbial growth to ultimately affect Drosophila lifespan. Fundamental food properties altered by dietary or drug interventions may therefore contribute to changes in animal physiology, metabolism, and

  1. Acidic Food pH Increases Palatability and Consumption and Extends Drosophila Lifespan.

    PubMed

    Deshpande, Sonali A; Yamada, Ryuichi; Mak, Christine M; Hunter, Brooke; Soto Obando, Alina; Hoxha, Sany; Ja, William W

    2015-12-01

    Despite the prevalent use of Drosophila as a model in studies of nutrition, the effects of fundamental food properties, such as pH, on animal health and behavior are not well known. We examined the effect of food pH on adult Drosophila lifespan, feeding behavior, and microbiota composition and tested the hypothesis that pH-mediated changes in palatability and total consumption are required for modulating longevity. We measured the effect of buffered food (pH 5, 7, or 9) on male gustatory responses (proboscis extension), total food intake, and male and female lifespan. The effect of food pH on germfree male lifespan was also assessed. Changes in fly-associated microbial composition as a result of food pH were determined by 16S ribosomal RNA gene sequencing. Male gustatory responses, total consumption, and male and female longevity were additionally measured in the taste-defective Pox neuro (Poxn) mutant and its transgenic rescue control. An acidic diet increased Drosophila gustatory responses (40-230%) and food intake (5-50%) and extended survival (10-160% longer median lifespan) compared with flies on either neutral or alkaline pH food. Alkaline food pH shifted the composition of fly-associated bacteria and resulted in greater lifespan extension (260% longer median survival) after microbes were eliminated compared with flies on an acidic (50%) or neutral (130%) diet. However, germfree flies lived longer on an acidic diet (5-20% longer median lifespan) compared with those on either neutral or alkaline pH food. Gustatory responses, total consumption, and longevity were unaffected by food pH in Poxn mutant flies. Food pH can directly influence palatability and feeding behavior and affect parameters such as microbial growth to ultimately affect Drosophila lifespan. Fundamental food properties altered by dietary or drug interventions may therefore contribute to changes in animal physiology, metabolism, and survival. © 2015 American Society for Nutrition.

  2. Supplementation with Major Royal-Jelly Proteins Increases Lifespan, Feeding, and Fecundity in Drosophila.

    PubMed

    Xin, Xiao-Xuan; Chen, Yong; Chen, Di; Xiao, Fa; Parnell, Laurence D; Zhao, Jing; Liu, Liang; Ordovas, Jose M; Lai, Chao-Qiang; Shen, Li-Rong

    2016-07-27

    The major royal-jelly proteins (MRJPs) are the main constituents responsible for the specific physiological role of royal jelly (RJ) in honeybees. Male and female Drosophila flies were fed diets containing either no MRJPs (A) or casein (B) at 1.25% (w/w) of diet or MRJPs at 1.25% (C), 2.50% (D), or 5.00% (E). Diets B, C, D, and E increased mean lifespan by 4.3%, 9.0%, 12.4%, and 13.9% in males and by 5.8%, 9.7%, 20.0%, and 11.8% in females in comparison to results from diet A, respectively. The diet supplemented with 2.50% MRJPs seems to have the optimal dose to improve both physiological and biochemical measures related to aging in both sexes. Interestingly, lifespan extension by MRJPs in Drosophila was positively associated with feeding and fecundity and up-regulation of copper and zinc-superoxide dismutase (CuZn-SOD) and the Egfr-mediated signaling pathway. This study provides strong evidence that MRJPs are important components of RJ for prolonging lifespan in Drosophila.

  3. Inhibition of FAAH confers increased stem cell migration via PPARα

    PubMed Central

    Wollank, Yvonne; Ramer, Robert; Ivanov, Igor; Salamon, Achim; Peters, Kirsten; Hinz, Burkhard

    2015-01-01

    Regenerative activity in tissues of mesenchymal origin depends on the migratory potential of mesenchymal stem cells (MSCs). The present study focused on inhibitors of the enzyme fatty acid amide hydrolase (FAAH), which catalyzes the degradation of endocannabinoids (anandamide, 2-arachidonoylglycerol) and endocannabinoid-like substances (N-oleoylethanolamine, N-palmitoylethanolamine). Boyden chamber assays, the FAAH inhibitors, URB597 and arachidonoyl serotonin (AA-5HT), were found to increase the migration of human adipose-derived MSCs. LC-MS analyses revealed increased levels of all four aforementioned FAAH substrates in MSCs incubated with either FAAH inhibitor. Following addition to MSCs, all FAAH substrates mimicked the promigratory action of FAAH inhibitors. Promigratory effects of FAAH inhibitors and substrates were causally linked to activation of p42/44 MAPKs, as well as to cytosol-to-nucleus translocation of the transcription factor, PPARα. Whereas PPARα activation by FAAH inhibitors and substrates became reversed upon inhibition of p42/44 MAPK activation, a blockade of PPARα left p42/44 MAPK phosphorylation unaltered. Collectively, these data demonstrate FAAH inhibitors and substrates to cause p42/44 MAPK phosphorylation, which subsequently activates PPARα to confer increased migration of MSCs. This novel pathway may be involved in regenerative effects of endocannabinoids whose degradation could be a target of pharmacological intervention by FAAH inhibitors. PMID:26263913

  4. Inhibition of FAAH confers increased stem cell migration via PPARα.

    PubMed

    Wollank, Yvonne; Ramer, Robert; Ivanov, Igor; Salamon, Achim; Peters, Kirsten; Hinz, Burkhard

    2015-10-01

    Regenerative activity in tissues of mesenchymal origin depends on the migratory potential of mesenchymal stem cells (MSCs). The present study focused on inhibitors of the enzyme fatty acid amide hydrolase (FAAH), which catalyzes the degradation of endocannabinoids (anandamide, 2-arachidonoylglycerol) and endocannabinoid-like substances (N-oleoylethanolamine, N-palmitoylethanolamine). Boyden chamber assays, the FAAH inhibitors, URB597 and arachidonoyl serotonin (AA-5HT), were found to increase the migration of human adipose-derived MSCs. LC-MS analyses revealed increased levels of all four aforementioned FAAH substrates in MSCs incubated with either FAAH inhibitor. Following addition to MSCs, all FAAH substrates mimicked the promigratory action of FAAH inhibitors. Promigratory effects of FAAH inhibitors and substrates were causally linked to activation of p42/44 MAPKs, as well as to cytosol-to-nucleus translocation of the transcription factor, PPARα. Whereas PPARα activation by FAAH inhibitors and substrates became reversed upon inhibition of p42/44 MAPK activation, a blockade of PPARα left p42/44 MAPK phosphorylation unaltered. Collectively, these data demonstrate FAAH inhibitors and substrates to cause p42/44 MAPK phosphorylation, which subsequently activates PPARα to confer increased migration of MSCs. This novel pathway may be involved in regenerative effects of endocannabinoids whose degradation could be a target of pharmacological intervention by FAAH inhibitors.

  5. Domain 2 of Drosophila para voltage-gated sodium channel confers insect properties to a rat brain channel.

    PubMed

    Shichor, Iris; Zlotkin, Eliahu; Ilan, Nitza; Chikashvili, Dodo; Stuhmer, Walter; Gordon, Dalia; Lotan, Ilana

    2002-06-01

    The ability of the excitatory anti-insect-selective scorpion toxin AahIT (Androctonus australis hector) to exclusively bind to and modify the insect voltage-gated sodium channel (NaCh) makes it a unique tool to unravel the structural differences between mammalian and insect channels, a prerequisite in the design of selective pesticides. To localize the insect NaCh domain that binds AahIT, we constructed a chimeric channel composed of rat brain NaCh alpha-subunit (rBIIA) in which domain-2 (D2) was replaced by that of Drosophila Para (paralytic temperature-sensitive). The choice of D2 was dictated by the similarity between AahIT and scorpion beta-toxins pertaining to both their binding and action and the essential role of D2 in the beta-toxins binding site on mammalian channels. Expression of the chimera rBIIA-ParaD2 in Xenopus oocytes gave rise to voltage-gated and TTX-sensitive NaChs that, like rBIIA, were sensitive to scorpion alpha-toxins and regulated by the auxiliary subunit beta(1) but not by the insect TipE. Notably, like Drosophila Para/TipE, but unlike rBIIA/beta(1), the chimera gained sensitivity to AahIT, indicating that the phyletic selectivity of AahIT is conferred by the insect NaCh D2. Furthermore, the chimera acquired additional insect channel properties; its activation was shifted to more positive potentials, and the effect of alpha-toxins was potentiated. Our results highlight the key role of D2 in the selective recognition of anti-insect excitatory toxins and in the modulation of NaCh gating. We also provide a methodological approach to the study of ion channels that are difficult to express in model expression systems.

  6. Beneficial effects of increased lysozyme levels in Alzheimer's disease modelled in Drosophila melanogaster.

    PubMed

    Sandin, Linnea; Bergkvist, Liza; Nath, Sangeeta; Kielkopf, Claudia; Janefjord, Camilla; Helmfors, Linda; Zetterberg, Henrik; Blennow, Kaj; Li, Hongyun; Nilsberth, Camilla; Garner, Brett; Brorsson, Ann-Christin; Kågedal, Katarina

    2016-10-01

    Genetic polymorphisms of immune genes that associate with higher risk to develop Alzheimer's disease (AD) have led to an increased research interest on the involvement of the immune system in AD pathogenesis. A link between amyloid pathology and immune gene expression was suggested in a genome-wide gene expression study of transgenic amyloid mouse models. In this study, the gene expression of lysozyme, a major player in the innate immune system, was found to be increased in a comparable pattern as the amyloid pathology developed in transgenic mouse models of AD. A similar pattern was seen at protein levels of lysozyme in human AD brain and CSF, but this lysozyme pattern was not seen in a tau transgenic mouse model. Lysozyme was demonstrated to be beneficial for different Drosophila melanogaster models of AD. In flies that expressed Aβ1-42 or AβPP together with BACE1 in the eyes, the rough eye phenotype indicative of toxicity was completely rescued by coexpression of lysozyme. In Drosophila flies bearing the Aβ1-42 variant with the Arctic gene mutation, lysozyme increased the fly survival and decreased locomotor dysfunction dose dependently. An interaction between lysozyme and Aβ1-42 in the Drosophila eye was discovered. We propose that the increased levels of lysozyme, seen in mouse models of AD and in human AD cases, were triggered by Aβ1-42 and caused a beneficial effect by binding of lysozyme to toxic species of Aβ1-42 , which prevented these from exerting their toxic effects. These results emphasize the possibility of lysozyme as biomarker and therapeutic target for AD. © 2016 The Authors. The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

  7. Splice form variant and amino acid changes in MDR49 confers DDT resistance in transgenic Drosophila.

    PubMed

    Seong, Keon Mook; Sun, Weilin; Clark, John M; Pittendrigh, Barry R

    2016-03-22

    The ATP-binding cassette (ABC) transporters represent a superfamily of proteins that have important physiological roles in both prokaryotes and eukaryotes. In insects, ABC transporters have previously been implicated in insecticide resistance. The 91-R strain of Drosophila melanogaster has been intensely selected with DDT over six decades. A recent selective sweeps analysis of 91-R implicated the potential role of MDR49, an ABC transporter, in DDT resistance, however, to date the details of how MDR49 may play a role in resistance have not been elucidated. In this study, we investigated the impact of structural changes and an alternative splicing event in MDR49 on DDT-resistance in 91-R, as compared to the DDT susceptible strain 91-C. We observed three amino acid differences in MDR49 when 91-R was compared with 91-C, and only one isoform (MDR49B) was implicated in DDT resistance. A transgenic Drosophila strain containing the 91-R-MDR49B isoform had a significantly higher LD50 value as compared to the 91-C-MDR49B isoform at the early time points (6 h to 12 h) during DDT exposure. Our data support the hypothesis that the MDR49B isoform, with three amino acid mutations, plays a role in the early aspects of DDT resistance in 91-R.

  8. Splice form variant and amino acid changes in MDR49 confers DDT resistance in transgenic Drosophila

    PubMed Central

    Seong, Keon Mook; Sun, Weilin; Clark, John M.; Pittendrigh, Barry R.

    2016-01-01

    The ATP-binding cassette (ABC) transporters represent a superfamily of proteins that have important physiological roles in both prokaryotes and eukaryotes. In insects, ABC transporters have previously been implicated in insecticide resistance. The 91-R strain of Drosophila melanogaster has been intensely selected with DDT over six decades. A recent selective sweeps analysis of 91-R implicated the potential role of MDR49, an ABC transporter, in DDT resistance, however, to date the details of how MDR49 may play a role in resistance have not been elucidated. In this study, we investigated the impact of structural changes and an alternative splicing event in MDR49 on DDT-resistance in 91-R, as compared to the DDT susceptible strain 91-C. We observed three amino acid differences in MDR49 when 91-R was compared with 91-C, and only one isoform (MDR49B) was implicated in DDT resistance. A transgenic Drosophila strain containing the 91-R-MDR49B isoform had a significantly higher LD50 value as compared to the 91-C-MDR49B isoform at the early time points (6 h to 12 h) during DDT exposure. Our data support the hypothesis that the MDR49B isoform, with three amino acid mutations, plays a role in the early aspects of DDT resistance in 91-R. PMID:27003579

  9. Ectopic expression of catalase in Drosophila mitochondria increases stress resistance but not longevity.

    PubMed

    Mockett, Robin J; Bayne, Anne Cécile V; Kwong, Linda K; Orr, William C; Sohal, Rajindar S

    2003-01-15

    The goal of this study was to test the hypothesis that the rate of mitochondrial oxidant production governs the aging process of the fruit fly, Drosophila melanogaster. Catalase, an antioxidative enzyme expressed in the cytosol and peroxisomes of Drosophila, was targetted ectopically to the mitochondrial matrix by fusion of a leader peptide derived from ornithine aminotransferase with its N-terminus. The presence of the transgene encoding this fusion protein was associated with moderate (35 +/- 13%) increases in total catalase activity in most lines, and measurable levels of catalase activity in the mitochondria (30-140 U/mg protein). There was no impact on the life span of the flies at 25 degrees C, even in an exceptional line with a 149% increase in total catalase activity, and there was a small decrease in longevity at 29 degrees C. There were no compensatory changes in the rate of metabolism or physical activity, or in the levels of other major antioxidants, suggesting that the aging process was largely unaffected. Resistance to exogenous hydrogen peroxide, paraquat, and cold stress was enhanced, but there was no appreciable effect on resistance to hyperoxia. The results demonstrate the importance of mitochondrial antioxidant levels in the resistance to oxidative stress at the organismal level, and illustrate that different effects on aging and stress resistance may ensue from a single treatment. The main inferences drawn are that: (i) levels of stress resistance may neither be a cause nor a reliable indicator of the rate of aging, and (ii) bolstering antioxidant levels in Drosophila may not delay or slow down the aging process.

  10. Distinct protein domains and expression patterns confer divergent axon guidance functions for Drosophila Robo receptors.

    PubMed

    Spitzweck, Bettina; Brankatschk, Marko; Dickson, Barry J

    2010-02-05

    The orthogonal array of axon pathways in the Drosophila CNS is constructed in part under the control of three Robo family axon guidance receptors: Robo1, Robo2 and Robo3. Each of these receptors is responsible for a distinct set of guidance decisions. To determine the molecular basis for these functional specializations, we used homologous recombination to create a series of 9 "robo swap" alleles: expressing each of the three Robo receptors from each of the three robo loci. We demonstrate that the lateral positioning of longitudinal axon pathways relies primarily on differences in gene regulation, not distinct combinations of Robo proteins as previously thought. In contrast, specific features of the Robo1 and Robo2 proteins contribute to their distinct functions in commissure formation. These specializations allow Robo1 to prevent crossing and Robo2 to promote crossing. These data demonstrate how diversification of expression and structure within a single family of guidance receptors can shape complex patterns of neuronal wiring.

  11. Extended life-span conferred by cotransporter gene mutations in Drosophila.

    PubMed

    Rogina, B; Reenan, R A; Nilsen, S P; Helfand, S L

    2000-12-15

    Aging is genetically determined and environmentally modulated. In a study of longevity in the adult fruit fly, Drosophila melanogaster, we found that five independent P-element insertional mutations in a single gene resulted in a near doubling of the average adult life-span without a decline in fertility or physical activity. Sequence analysis revealed that the product of this gene, named Indy (for I'm not dead yet), is most closely related to a mammalian sodium dicarboxylate cotransporter-a membrane protein that transports Krebs cycle intermediates. Indy was most abundantly expressed in the fat body, midgut, and oenocytes: the principal sites of intermediary metabolism in the fly. Excision of the P element resulted in a reversion to normal life-span. These mutations may create a metabolic state that mimics caloric restriction, which has been shown to extend life-span.

  12. A transposable P vector that confers selectable G418 resistance to Drosophila larvae.

    PubMed

    Steller, H; Pirrotta, V

    1985-01-01

    Drosophila larvae are rapidly killed by food containing the antibiotic G418. The bacterial gene for neomycin resistance introduced in the genome by P-mediated transformation renders larvae resistant to G418 and able to grow to fertile adults. The neo gene transcribed from the herpes thymidine kinase promoter gives low levels of resistance but high levels can be obtained using the hsp70 heat-shock promoter. We have constructed a vector for P-mediated transformation which uses this finding to allow dominant selection of transformed progeny. Features of this vector also facilitate cloning and allow the rapid recovery of the inserted transposon from transformed flies. We have also constructed a cosmid vector for P-mediated transformation that incorporates the hsp70-neo gene.

  13. Sumoylation is tumor-suppressive and confers proliferative quiescence to hematopoietic progenitors in Drosophila melanogaster larvae.

    PubMed

    Kalamarz, Marta E; Paddibhatla, Indira; Nadar, Christina; Govind, Shubha

    2012-03-15

    How cell-intrinsic regulation of the cell cycle and the extrinsic influence of the niche converge to provide proliferative quiescence, safeguard tissue integrity, and provide avenues to stop stem cells from giving rise to tumors is a major challenge in gene therapy and tissue engineering. We explore this question in sumoylation-deficient mutants of Drosophila. In wild type third instar larval lymph glands, a group of hematopoietic stem/progenitor cells acquires quiescence; a multicellular niche supports their undifferentiated state. However, how proliferative quiescence is instilled in this population is not understood. We show that Ubc9 protein is nuclear in this population. Loss of the SUMO-activating E1 enzyme, Aos1/Uba2, the conjugating E2 enzyme, Ubc9, or the E3 SUMO ligase, PIAS, results in a failure of progenitors to quiesce; progenitors become hyperplastic, misdifferentiate, and develop into microtumors that eventually detach from the dorsal vessel. Significantly, dysplasia and lethality of Ubc9 mutants are rescued when Ubc9(wt) is provided specifically in the progenitor populations, but not when it is provided in the niche or in the differentiated cortex. While normal progenitors express high levels of the Drosophila cyclin-dependent kinase inhibitor p21 homolog, Dacapo, the corresponding overgrown mutant population exhibits a marked reduction in Dacapo. Forced expression of either Dacapo or human p21 in progenitors shrinks this population. The selective expression of either protein in mutant progenitor cells, but not in other hematopoietic populations, limits overgrowth, blocks tumorogenesis, and restores organ integrity. We discuss an essential and complex role for sumoylation in preserving the hematopoietic progenitor states for stress response and in the context of normal development of the fly.

  14. Sumoylation is tumor-suppressive and confers proliferative quiescence to hematopoietic progenitors in Drosophila melanogaster larvae

    PubMed Central

    Kalamarz, Marta E.; Paddibhatla, Indira; Nadar, Christina; Govind, Shubha

    2012-01-01

    Summary How cell-intrinsic regulation of the cell cycle and the extrinsic influence of the niche converge to provide proliferative quiescence, safeguard tissue integrity, and provide avenues to stop stem cells from giving rise to tumors is a major challenge in gene therapy and tissue engineering. We explore this question in sumoylation-deficient mutants of Drosophila. In wild type third instar larval lymph glands, a group of hematopoietic stem/progenitor cells acquires quiescence; a multicellular niche supports their undifferentiated state. However, how proliferative quiescence is instilled in this population is not understood. We show that Ubc9 protein is nuclear in this population. Loss of the SUMO-activating E1 enzyme, Aos1/Uba2, the conjugating E2 enzyme, Ubc9, or the E3 SUMO ligase, PIAS, results in a failure of progenitors to quiesce; progenitors become hyperplastic, misdifferentiate, and develop into microtumors that eventually detach from the dorsal vessel. Significantly, dysplasia and lethality of Ubc9 mutants are rescued when Ubc9wt is provided specifically in the progenitor populations, but not when it is provided in the niche or in the differentiated cortex. While normal progenitors express high levels of the Drosophila cyclin-dependent kinase inhibitor p21 homolog, Dacapo, the corresponding overgrown mutant population exhibits a marked reduction in Dacapo. Forced expression of either Dacapo or human p21 in progenitors shrinks this population. The selective expression of either protein in mutant progenitor cells, but not in other hematopoietic populations, limits overgrowth, blocks tumorogenesis, and restores organ integrity. We discuss an essential and complex role for sumoylation in preserving the hematopoietic progenitor states for stress response and in the context of normal development of the fly. PMID:23213407

  15. Spaceflight Causes Increased Virulence of Serratia Marcescens on a Drosophila Melanogaster Host

    NASA Technical Reports Server (NTRS)

    Bhattacharya, Sharmila; Wade, William; Clemens-Grisham, Rachel; Hosamani, Ravikumar; Bhardwaj, Shilpa R.; Lera, Matthew P.; Gresser, Amy L.

    2015-01-01

    Drosophila melanogaster, or the fruit fly, has long been an important organism for Earth-based research, and is now increasingly utilized as a model system to understand the biological effects of spaceflight. Studies in Drosophila melanogaster have shown altered immune responses in 3rd instar larvae and adult males following spaceflight, changes similar to those observed in astronauts. In addition, spaceflight has also been shown to affect bacterial physiology, as evidenced by studies describing altered virulence of Salmonella typhimurium following spaceflight and variation in biofilm growth patterns for the opportunistic pathogen Pseudomonas aeruginosa during flight. We recently sent Serratia marcescens Db11, a Drosophila pathogen and an opportunistic human pathogen, to the ISS on SpaceX-5 (Fruit Fly Lab-01). S. marcescens samples were stored at 4degC for 24 days on-orbit and then allowed to grow for 120 hours at ambient station temperature before being returned to Earth. Upon return, bacteria were isolated and preserved in 50% glycerol or RNAlater. Storage, growth, and isolation for ground control samples were performed using the same procedures. Spaceflight and ground samples stored in 50% glycerol were diluted and injected into 5-7-day-old ground-born adult D. melanogaster. Lethality was significantly greater in flies injected with the spaceflight samples compared to those injected with ground bacterial samples. These results indicate a shift in the virulence profile of the spaceflight S. marcescens Db11 and will be further assessed with molecular biological analyses. Our findings strengthen the conclusion that spaceflight impacts the virulence of bacterial pathogens on model host organisms such as the fruit fly. This research was supported by NASA's ISS Program Office (ISSPO) and Space Life and Physical Sciences Research and Applications (SLPSRA).

  16. Sexual activity increases resistance against Pseudomonas entomophila in male Drosophila melanogaster

    PubMed Central

    2013-01-01

    Background Maintenance and deployment cost of immunity is high, therefore, it is expected to trade-off with other high cost traits like sexual activity. Previous studies with Drosophila melanogaster show that male’s ability to clear bacteria decreases with increase in sexual activity. We subjected this idea to test using two pathogens (Pseudomonas entomophila and Staphylococcus succinus) and three different populations of Drosophila melanogaster. Results We found that sexual activity enhanced male survivorship in a pathogen specific manner. Sexually active males show higher resistance than virgins upon infection with Pseudomonas entomophila. Interestingly, the beneficial effects of sexual activity increased with time of co-habitation with females and declined when access to females was restricted. We observed no change in male survivorship upon experimentally varying the number of sexual interactions. Conclusion Our results show that the sexual activity-immunity trade-off in males cannot be generalised. The trade-off is potentially mediated through complex interactions between the host, pathogen and the environment experienced by the host. PMID:24010544

  17. Epigallocatechin gallate affects glucose metabolism and increases fitness and lifespan in Drosophila melanogaster

    PubMed Central

    Wagner, Anika E.; Piegholdt, Stefanie; Rabe, Doerte; Baenas, Nieves; Schloesser, Anke; Eggersdorfer, Manfred; Stocker, Achim; Rimbach, Gerald

    2015-01-01

    In this study, we tested whether a standardized epigallocatechin-3-gallate (EGCG) rich green tea extract (comprising > 90% EGCG) affects fitness and lifespan as well as parameters of glucose metabolism and energy homeostasis in the fruit fly, Drosophila melanogaster. Following the application of the green tea extract a significant increase in the mean lifespan (+ 3.3 days) and the 50% survival (+ 4.3 days) as well as improved fitness was detected. These effects went along an increased expression of Spargel, the homolog of mammalian PGC1α, which has been reported to affect lifespan in flies. Intriguingly, in flies, treatment with the green tea extract decreased glucose concentrations, which were accompanied by an inhibition of α-amylase and α-glucosidase activity. Computational docking analysis proved the potential of EGCG to dock into the substrate binding pocket of α-amylase and to a greater extent into α-glucosidase. Furthermore, we demonstrate that EGCG downregulates insulin-like peptide 5 and phosphoenolpyruvate carboxykinase, major regulators of glucose metabolism, as well as the Drosophila homolog of leptin, unpaired 2. We propose that a decrease in glucose metabolism in connection with an upregulated expression of Spargel contribute to the better fitness and the extended lifespan in EGCG-treated flies. PMID:26375250

  18. Epigallocatechin gallate affects glucose metabolism and increases fitness and lifespan in Drosophila melanogaster.

    PubMed

    Wagner, Anika E; Piegholdt, Stefanie; Rabe, Doerte; Baenas, Nieves; Schloesser, Anke; Eggersdorfer, Manfred; Stocker, Achim; Rimbach, Gerald

    2015-10-13

    In this study, we tested whether a standardized epigallocatechin-3-gallate (EGCG) rich green tea extract (comprising > 90% EGCG) affects fitness and lifespan as well as parameters of glucose metabolism and energy homeostasis in the fruit fly, Drosophila melanogaster. Following the application of the green tea extract a significant increase in the mean lifespan (+ 3.3 days) and the 50% survival (+ 4.3 days) as well as improved fitness was detected. These effects went along an increased expression of Spargel, the homolog of mammalian PGC1α, which has been reported to affect lifespan in flies. Intriguingly, in flies, treatment with the green tea extract decreased glucose concentrations, which were accompanied by an inhibition of α-amylase and α-glucosidase activity. Computational docking analysis proved the potential of EGCG to dock into the substrate binding pocket of α-amylase and to a greater extent into α-glucosidase. Furthermore, we demonstrate that EGCG downregulates insulin-like peptide 5 and phosphoenolpyruvate carboxykinase, major regulators of glucose metabolism, as well as the Drosophila homolog of leptin, unpaired 2. We propose that a decrease in glucose metabolism in connection with an upregulated expression of Spargel contribute to the better fitness and the extended lifespan in EGCG-treated flies.

  19. Successive increases in the resistance of Drosophila to viral infection through a transposon insertion followed by a Duplication.

    PubMed

    Magwire, Michael M; Bayer, Florian; Webster, Claire L; Cao, Chuan; Jiggins, Francis M

    2011-10-01

    To understand the molecular basis of how hosts evolve resistance to their parasites, we have investigated the genes that cause variation in the susceptibility of Drosophila melanogaster to viral infection. Using a host-specific pathogen of D. melanogaster called the sigma virus (Rhabdoviridae), we mapped a major-effect polymorphism to a region containing two paralogous genes called CHKov1 and CHKov2. In a panel of inbred fly lines, we found that a transposable element insertion in the protein coding sequence of CHKov1 is associated with increased resistance to infection. Previous research has shown that this insertion results in a truncated messenger RNA that encodes a far shorter protein than the susceptible allele. This resistant allele has rapidly increased in frequency under directional selection and is now the commonest form of the gene in natural populations. Using genetic mapping and site-specific recombination, we identified a third genotype with considerably greater resistance that is currently rare in the wild. In these flies there have been two duplications, resulting in three copies of both the truncated allele of CHKov1 and CHKov2 (one of which is also truncated). Remarkably, the truncated allele of CHKov1 has previously been found to confer resistance to organophosphate insecticides. As estimates of the age of this allele predate the use of insecticides, it is likely that this allele initially functioned as a defence against viruses and fortuitously "pre-adapted" flies to insecticides. These results demonstrate that strong selection by parasites for increased host resistance can result in major genetic changes and rapid shifts in allele frequencies; and, contrary to the prevailing view that resistance to pathogens can be a costly trait to evolve, the pleiotropic effects of these changes can have unexpected benefits.

  20. PEPTIDASE INCREASE ACCOMPANYING GROWTH OF THE LARVAL SALIVARY GLAND OF DROSOPHILA MELANOGASTER

    PubMed Central

    Patterson, Elizabeth K.; Dackerman, Marjorie E.; Schultz, Jack

    1949-01-01

    1. The larval salivary gland of Drosophila melanogaster offers an opportunity to study growth in a tissue in which no cell division occurs but in which the cells increase in size. 2. Measurements of alanylglycine (AG)-peptidase content have been made in three stocks of Drosophila melanogaster at different growth stages of the larval salivary gland, and have been correlated with its total nitrogen and volume. 3. During the prepupal instar, the AG-peptidase content of the gland increases parallel with total nitrogen but decreases when histolysis of the gland begins. Conversely, a benzoyl-l-arginineamide-hydrolyzing endopeptidase is not measurable until histolysis sets in. 4. In the final larval growth period of a giant mutant, there is a concomitant increase in peptidase, total nitrogen, and volume of the gland. 5. A similar association of peptidase content and total nitrogen is found in comparing glands of different sizes from the giant stock, at the time of maximal peptidase content in the prepupa. 6. The data are interpreted as evidence for an association of AG-peptidase with growth of the cells in the gland. This agrees with the earlier interpretation by Linderstrøm-Lang and Holter of data obtained from study of more complex tissues. 7. A survey of the available measurements of peptidase content in other organisms shows that wherever an increase of cell substance occurs, peptidase content increases. Conversely, peptidase remains constant where cell division is unaccompanied by an increase of cell substances. 8. The joint association of peptidases and pentosenucleic acids with protein synthesis is pointed out. 9. The possiblity is considered that peptidases may be essential parts of a unit in which coupled reactions necessary for protein synthesis occur. The rôle of the peptidases in this system is discussed. They may act either synthetically to form new peptide linkages (problematic), or hydrolytically to mobilize the necessary specific amino acids. PMID

  1. Increased longevity mediated by yeast NDI1 expression in Drosophila intestinal stem and progenitor cells

    PubMed Central

    Hur, Jae H.; Bahadorani, Sepehr; Graniel, Jacqueline; Koehler, Christopher L.; Ulgherait, Matthew; Rera, Michael; Jones, D. Leanne; Walker, David W.

    2013-01-01

    A functional decline in tissue stem cells and mitochondrial dysfunction have each been linked to aging and multiple aging-associated pathologies. However, the interplay between energy homeostasis, stem cells, and organismal aging remains poorly understood. Here, we report that expression of the single-subunit yeast alternative NADH dehydrogenase, ndi1, in Drosophila intestinal stem and progenitor cells delays the onset of multiple markers of intestinal aging and extends lifespan. In addition, expression of ndi1 in the intestine increases feeding behavior and results in organismal weight gain. Consistent with increased nutrient uptake, flies expressing ndi1 in the digestive tract display a systemic reduction in the activity of AMP-activated protein kinase (AMPK), a key cellular energy sensor. Together, these results demonstrate that ndi1 expression in the intestinal epithelium is an effective strategy to delay tissue and organismal aging. PMID:24038661

  2. Lifespan extension by increased expression of the Drosophila homologue of the IGFBP7 tumour suppressor

    PubMed Central

    Alic, Nazif; Hoddinott, Matthew P; Vinti, Giovanna; Partridge, Linda

    2011-01-01

    Mammals possess multiple insulin-like growth factor (IGF) binding proteins (IGFBPs), and related proteins, that modulate the activity of insulin/IGF signalling (IIS), a conserved neuroendocrine signalling pathway that affects animal lifespan. Here, we examine if increased levels of an IGFBP-like protein can extend lifespan, using Drosophila as the model organism. We demonstrate that Imaginal morphogenesis protein-Late 2 (IMP-L2), a secreted protein and the fly homologue of the human IGFBP7 tumour suppressor, is capable of binding at least two of the seven Drosophila insulin-like peptides (DILPs), namely native DILP2 and DILP5 as present in the adult fly. Increased expression of Imp-L2 results in phenotypic changes in the adult consistent with down-regulation of IIS, including accumulation of eIF-4E binding protein mRNA, increase in storage lipids, reduced fecundity and enhanced oxidative stress resistance. Increased Imp-L2 results in up-regulation of dilp2, dilp3 and dilp5 mRNA, revealing a feedback circuit that is mediated via the fly gut and/or fat body. Importantly, over-expression of Imp-L2, ubiquitous or restricted to DILP-producing cells or gut and fat body, extends lifespan. This enhanced longevity can also be observed upon adult-onset induction of Imp-L2, indicating it is not attributable to developmental changes. Our findings point to the possibility that an IGFBP or a related protein, such as IGFBP7, plays a role in mammalian aging. PMID:21108726

  3. Suppression of a Lethal Trisomic Phenotype in Drosophila Melanogaster by Increased Dosage of an Unlinked Locus

    PubMed Central

    Dorer, D. R.; Cadden, M. A.; Gordesky-Gold, B.; Harries, G.; Christensen, A. C.

    1993-01-01

    One of the most extreme examples of gene dosage sensitivity is the Triplo-lethal locus (Tpl) on the third chromosome of Drosophila melanogaster, which is lethal when present in either one or three copies. Increased dosage of an unlinked locus, Isis, suppresses the triplo-lethal phenotype of Tpl, but not the haplo-lethal phenotype. We have mapped Isis to the X chromosome region 7E3-8A5, and shown that the suppression is a gene dosage effect. Altered dosage of Isis in the presence of two copies of Tpl has no obvious effects. By examining the interactions between Isis dosage and Tpl we suggest that Isis does not directly repress Tpl expression, but acts downstream on the triplo-lethal phenotype of Tpl. PMID:8514133

  4. Irradiation-resistance conferred by superoxide dismutase: possible adaptive role of a natural polymorphism in Drosophila melanogaster

    SciTech Connect

    Peng, T.X.; Moya, A.; Ayala, F.J.

    1986-02-01

    The toxic effects of ionizing radiation to DNA are thought to be due to the generation of the superoxide radical, 02-. Superoxide dismutase (SOD), which scavenges 02-., has been invoked as a protecting enzyme against ionizing radiation in viruses, bacteria, mammalian cells in culture, and live mice. We now demonstrate that SOD is involved in the resistance of Drosophila melanogaster against irradiation. The protection is greatest when flies carry the S form of the enzyme (which exhibits highest in vitro specific activity), intermediate when they carry the F form of the enzyme, and lowest when they are homozygous for N, an allele that reduces the amount of the enzyme to 3.5% of the normal level. Natural selection experiments show that the fitness of the high-activity S allele is increased in an irradiated population relative to the nonirradiated control. These results point towards a possible adaptive function of the S/F polymorphism found in natural populations of D. melanogaster.

  5. Longevity for free? Increased reproduction with limited trade-offs in Drosophila melanogaster selected for increased life span.

    PubMed

    Wit, Janneke; Sarup, Pernille; Lupsa, Nikolett; Malte, Hans; Frydenberg, Jane; Loeschcke, Volker

    2013-03-01

    Selection for increased life span in Drosophila melanogaster has been shown to correlate with decreased early fecundity and increased fecundity later in life. This phenomenon has been ascribed to the existence of trade-offs in which limited resources can be invested in either somatic maintenance or reproduction. In our longevity selection lines, we did not find such a trade-off. Rather, we find that females have similar or higher fecundity throughout life compared to non-selected controls. To determine whether increased longevity affects responses in other traits, we looked at several stress resistance traits (chill coma recovery, heat knockdown, desiccation and starvation), geotactic behaviour, egg-to-adult viability, body size, developmental time as well as metabolic rate. Longevity selected flies were more starvation resistant. However, in females longevity and fecundity were not negatively correlated with the other traits assayed. Males from longevity selected lines were slower at recovering from a chill induced coma and resting metabolic rate increased with age, but did not correlate with life span. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Mating-Induced Increase in Germline Stem Cells via the Neuroendocrine System in Female Drosophila

    PubMed Central

    Ameku, Tomotsune

    2016-01-01

    Mating and gametogenesis are two essential components of animal reproduction. Gametogenesis must be modulated by the need for gametes, yet little is known of how mating, a process that utilizes gametes, may modulate the process of gametogenesis. Here, we report that mating stimulates female germline stem cell (GSC) proliferation in Drosophila melanogaster. Mating-induced increase in GSC number is not simply owing to the indirect effect of emission of stored eggs, but rather is stimulated by a male-derived Sex Peptide (SP) and its receptor SPR, the components of a canonical neuronal pathway that induces a post-mating behavioral switch in females. We show that ecdysteroid, the major insect steroid hormone, regulates mating-induced GSC proliferation independently of insulin signaling. Ovarian ecdysteroid level increases after mating and transmits its signal directly through the ecdysone receptor expressed in the ovarian niche to increase the number of GSCs. Impairment of ovarian ecdysteroid biosynthesis disrupts mating-induced increase in GSCs as well as egg production. Importantly, feeding of ecdysteroid rescues the decrease in GSC number caused by impairment of neuronal SP signaling. Our study illustrates how female GSC activity is coordinately regulated by the neuroendocrine system to sustain reproductive success in response to mating. PMID:27310920

  7. Quantifying the life-history response to increased male exposure in female Drosophila melanogaster.

    PubMed

    Edward, Dominic A; Fricke, Claudia; Gerrard, Dave T; Chapman, Tracey

    2011-02-01

    Precise estimates of costs and benefits, the fitness economics, of mating are of key importance in understanding how selection shapes the coevolution of male and female mating traits. However, fitness is difficult to define and quantify. Here, we used a novel application of an established analytical technique to calculate individual- and population-based estimates of fitness-including those sensitive to the timing of reproduction-to measure the effects on females of increased exposure to males. Drosophila melanogaster females were exposed to high and low frequencies of contact with males, and life-history traits for each individual female were recorded. We then compared different fitness estimates to determine which of them best described the changes in life histories. We predicted that rate-sensitive estimates would be more accurate, as mating influences the rate of offspring production in this species. The results supported this prediction. Increased exposure to males led to significantly decreased fitness within declining but not stable or increasing populations. There was a net benefit of increased male exposure in expanding populations, despite a significant decrease in lifespan. The study shows how a more accurate description of fitness, and new insights can be achieved by considering individual life-history strategies within the context of population growth.

  8. Evolution of increased adult longevity in Drosophila melanogaster populations selected for adaptation to larval crowding.

    PubMed

    Shenoi, V N; Ali, S Z; Prasad, N G

    2016-02-01

    In holometabolous animals such as Drosophila melanogaster, larval crowding can affect a wide range of larval and adult traits. Adults emerging from high larval density cultures have smaller body size and increased mean life span compared to flies emerging from low larval density cultures. Therefore, adaptation to larval crowding could potentially affect adult longevity as a correlated response. We addressed this issue by studying a set of large, outbred populations of D. melanogaster, experimentally evolved for adaptation to larval crowding for 83 generations. We assayed longevity of adult flies from both selected (MCUs) and control populations (MBs) after growing them at different larval densities. We found that MCUs have evolved increased mean longevity compared to MBs at all larval densities. The interaction between selection regime and larval density was not significant, indicating that the density dependence of mean longevity had not evolved in the MCU populations. The increase in longevity in MCUs can be partially attributed to their lower rates of ageing. It is also noteworthy that reaction norm of dry body weight, a trait probably under direct selection in our populations, has indeed evolved in MCU populations. To the best of our knowledge, this is the first report of the evolution of adult longevity as a correlated response of adaptation to larval crowding.

  9. Fruiting bodies of the social amoeba Dictyostelium discoideum increase spore transport by Drosophila

    PubMed Central

    2014-01-01

    Background Many microbial phenotypes are the product of cooperative interactions among cells, but their putative fitness benefits are often not well understood. In the cellular slime mold Dictyostelium discoideum, unicellular amoebae aggregate when starved and form multicellular fruiting bodies in which stress-resistant spores are held aloft by dead stalk cells. Fruiting bodies are thought to be adaptations for dispersing spores to new feeding sites, but this has not been directly tested. Here we experimentally test whether fruiting bodies increase the rate at which spores are acquired by passing invertebrates. Results Drosophila melanogaster accumulate spores on their surfaces more quickly when exposed to intact fruiting bodies than when exposed to fruiting bodies physically disrupted to dislodge spore masses from stalks. Flies also ingest and excrete spores that still express a red fluorescent protein marker. Conclusions Multicellular fruiting bodies created by D. discoideum increase the likelihood that invertebrates acquire spores that can then be transported to new feeding sites. These results thus support the long-hypothesized dispersal benefits of altruism in a model system for microbial cooperation. PMID:24884856

  10. Minocycline, but not ascorbic acid, increases motor activity and extends the life span of Drosophila melanogaster.

    PubMed

    Mora, Marylhi; Medina-Leendertz, Shirley J; Bonilla, Ernesto; Terán, Raikelin E; Paz, Milagros C; Arcaya, José Luis

    2013-06-01

    In the present study we compared the effects of minocycline and ascorbic acid in the life span, motor activity and lipid peroxidation of Drosophila melanogaster, in an effort to find a substance capable of providing protection against oxidative stress in aging. In the flies treated with minocycline a very significant increase in the life span (101 +/- 1.33 days) was observed when compared to those treated with ascorbic acid and controls (42.3% and 38.4%, respectively). The motor activity of minocycline treated flies also increased significantly with respect to control and ascorbic acid fed flies, from the 3rd to the 9th week of treatment. With regard to lipid peroxidation, it was found that the levels of malondialdehyde (MDA) in flies treated with minocycline showed no statistical differences to the control on the first day of treatment, but a significantly lower content on the day of 50% survival. In contrast, in flies treated with ascorbic acid significantly elevated levels of MDA compared to control and minocycline treated flies were detected throughout. These results suggest a protective effect of minocycline against oxidative stress and aging in D. melanogaster. An inhibitory effect on reactive oxygen species production may be an important contributing factor.

  11. Increased autophagy and apoptosis contribute to muscle atrophy in a myotonic dystrophy type 1 Drosophila model.

    PubMed

    Bargiela, Ariadna; Cerro-Herreros, Estefanía; Fernandez-Costa, Juan M; Vilchez, Juan J; Llamusi, Beatriz; Artero, Ruben

    2015-07-01

    Muscle mass wasting is one of the most debilitating symptoms of myotonic dystrophy type 1 (DM1) disease, ultimately leading to immobility, respiratory defects, dysarthria, dysphagia and death in advanced stages of the disease. In order to study the molecular mechanisms leading to the degenerative loss of adult muscle tissue in DM1, we generated an inducible Drosophila model of expanded CTG trinucleotide repeat toxicity that resembles an adult-onset form of the disease. Heat-shock induced expression of 480 CUG repeats in adult flies resulted in a reduction in the area of the indirect flight muscles. In these model flies, reduction of muscle area was concomitant with increased apoptosis and autophagy. Inhibition of apoptosis or autophagy mediated by the overexpression of DIAP1, mTOR (also known as Tor) or muscleblind, or by RNA interference (RNAi)-mediated silencing of autophagy regulatory genes, achieved a rescue of the muscle-loss phenotype. In fact, mTOR overexpression rescued muscle size to a size comparable to that in control flies. These results were validated in skeletal muscle biopsies from DM1 patients in which we found downregulated autophagy and apoptosis repressor genes, and also in DM1 myoblasts where we found increased autophagy. These findings provide new insights into the signaling pathways involved in DM1 disease pathogenesis.

  12. Food deprivation increases the low-dose locomotor stimulant response to ethanol in Drosophila melanogaster.

    PubMed

    Kliethermes, Christopher L

    2013-10-01

    Acute and chronic states of food deprivation result in increased sensitivity to a variety of natural reinforcers as well as to drugs of abuse. Food deprived animals show increased locomotor activity during periods of food deprivation, as well as increased locomotor stimulant responses to drugs of abuse, including cocaine, amphetamine, morphine, and ethanol, implying that drugs of abuse act in part on neural systems that underlie responses towards food. To determine whether this effect extends to an invertebrate, highly genetically tractable animal, the locomotor stimulant effects of low dose ethanol were assessed under a variety of feeding conditions in the fruit fly, Drosophila melanogaster. Food deprivation resulted in strain specific increases in ethanol-stimulated locomotor activity in most strains tested, although elevated baseline activity confounded interpretation in some strains. Experiments conducted with Canton S flies found that the effects of food deprivation on the locomotor stimulant response to ethanol increased with the duration of deprivation, and could be blocked by refeeding the flies with standard food or sucrose, but not yeast, immediately prior to the ethanol exposure. Life-span extending dietary depletion procedures or previous periods of food deprivation did not affect the response to ethanol, indicating that only animals in an acutely food deprived state are more sensitive to the stimulant effects of ethanol. These results suggest that increased sensitivity to the stimulant effects of some drugs of abuse might reflect an evolutionarily conserved neural mechanism that underlies behavioral responses to natural reinforcers and drugs of abuse. The identification of this mechanism, and the genes that underlie its development and function, will constitute a novel approach towards the study of alcohol abuse and dependence.

  13. Laboratory selection for increased longevity in Drosophila melanogaster reduces field performance.

    PubMed

    Wit, Janneke; Kristensen, Torsten Nygaard; Sarup, Pernille; Frydenberg, Jane; Loeschcke, Volker

    2013-11-01

    Drosophila melanogaster is frequently used in ageing studies to elucidate which mechanisms determine the onset and progress of senescence. Lines selected for increased longevity have often been shown to perform as well as or superior to control lines in life history, stress resistance and behavioural traits when tested in the laboratory. Functional senescence in longevity selected lines has also been shown to occur at a slower rate. However, it is known that performance in a controlled laboratory setting is not necessarily representative of performance in nature. In this study the effect of ageing, environmental temperature and longevity selection on performance in the field was tested. Flies from longevity selected and control lines of different ages (2, 5, 10 and 15 days) were released in an environment free of natural food sources. Control flies were tested at low, intermediate and high temperatures, while longevity selected flies were tested at the intermediate temperature only. The ability of flies to locate and reach a food source was tested. Flies of intermediate age were generally better at locating resources than both younger and older flies, where hot and cold environments accelerate the senescent decline in performance. Control lines were better able to locate a resource compared to longevity selected lines of the same age, suggesting that longevity comes at a cost in early life field fitness, supporting the antagonistic pleiotropy theory of ageing.

  14. Extension of Drosophila lifespan by Rosa damascena associated with an increased sensitivity to heat.

    PubMed

    Schriner, Samuel E; Katoozi, Niki S; Pham, Kevin Q; Gazarian, Maral; Zarban, Asghar; Jafari, Mahtab

    2012-04-01

    Rosa damascena, or Damask rose, is a rose hybrid commonly harvested for rose oil used in perfumery and for rose water used to flavor food. The petal extract of R. damascena was recently found to decrease Drosophila melanogaster mortality without impairing reproductive fitness or metabolic rate. Here, we report that R. damascena extended both mean and maximum lifespan of the fly. The extract also protected against oxidative stress in flies, predominantly in females. However, it did not alter mitochondrial respiration or content, superoxide production, or the major antioxidant defenses, superoxide dismutase and catalase. The extract increased survival in both sexes when exposed to reduced iron, though surprisingly, it sensitized both sexes to heat stress (survival at 37°C), and appeared to down-regulate the major heat shock protein HSP70 and the small mitochondrial heat shock protein HSP22, at 25°C and after heat shock (4 h at 37°C). We hypothesize that R. damascena extends lifespan by protecting against iron, which concomitantly leads to decreased HSP expression and compromising heat tolerance.

  15. Extension of Drosophila lifespan by Rosa damascena associated with an increased sensitivity to heat

    PubMed Central

    Schriner, Samuel E.; Katoozi, Niki S.; Pham, Kevin Q.; Gazarian, Maral; Zarban, Asghar; Jafari, Mahtab

    2011-01-01

    Rosa damascena, or Damask rose, is a rose hybrid commonly harvested for rose oil used in perfumery and for rose water used to flavor food. The petal extract of R. damascena was recently found to decrease Drosophila melanogaster mortality without impairing reproductive fitness or metabolic rate. Here, we report that R. damascena extended both mean and maximum lifespan of the fly. The extract also protected against oxidative stress in flies, predominantly in females. However, it did not alter mitochondrial respiration or content, superoxide production, or the major antioxidant defenses, superoxide dismutase and catalase. The extract increased survival in both sexes when exposed to reduced iron, though surprisingly, it sensitized both sexes to heat stress (survival at 37° C), and appeared to down-regulate the major heat shock protein HSP70 and the small mitochondrial heat shock protein HSP22, at 25° C and after heat shock (4 hours at 37° C). We hypothesize that R. damascena extends lifespan by protecting against iron, which concomitantly leads to decreased HSP expression and compromising heat tolerance. PMID:21928072

  16. Ageing increases vulnerability to aβ42 toxicity in Drosophila.

    PubMed

    Rogers, Iain; Kerr, Fiona; Martinez, Pedro; Hardy, John; Lovestone, Simon; Partridge, Linda

    2012-01-01

    Age is the major risk factor for many neurodegenerative diseases, including Alzheimer's Disease (AD), for reasons that are not clear. The association could indicate that the duration or degree of exposure to toxic proteins is important for pathology, or that age itself increases susceptibility to protein toxicity. Using an inducible Drosophila model of AD, we investigated these possibilities by varying the expression of an Aβ42 transgene in neurons at different adult ages and measuring the effects on Aβ42 levels and associated pathological phenotypes. Acute induction of Arctic Aβ42 in young adult flies resulted in rapid expression and clearance of mRNA and soluble Arctic Aβ42 protein, but in irreversible expression of insoluble Arctic Aβ42 peptide. Arctic Aβ42 peptide levels accumulated with longer durations of induction, and this led to a dose-dependent reduction in negative geotaxis and lifespan. For a standardised level of mRNA expression, older flies had higher levels of Arctic Aβ42 peptide and associated toxicity, and this correlated with an age-dependent reduction in proteasome activity. Equalising Aβ42 protein at different ages shortened lifespan in correlation with the duration of exposure to the peptide, suggesting that Aβ42 expression accumulates damage over time. However, the relative reduction in lifespan compared to controls was greater in flies first exposed to the peptide at older ages, suggesting that ageing itself also increases susceptibility to Aβ42 toxicity. Indeed older flies were more vulnerable to chronic Aβ42 toxicity even with a much lower lifetime exposure to the peptide. Finally, the persistence of insoluble Aβ42 in both young and old induced flies suggests that aggregated forms of the peptide cause toxicity in later life. Our results suggest that reduced protein turnover, increased duration of exposure and increased vulnerability to protein toxicity at later ages in combination could explain the late age-of-onset of

  17. An integrated optical coherence microscopy imaging and optical stimulation system for optogenetic pacing in Drosophila melanogaster (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Alex, Aneesh; Li, Airong; Men, Jing; Jerwick, Jason; Tanzi, Rudolph E.; Zhou, Chao

    2016-03-01

    Electrical stimulation is the clinical standard for cardiac pacing. Although highly effective in controlling cardiac rhythm, the invasive nature, non-specificity to cardiac tissues and possible tissue damage limits its applications. Optogenetic pacing of the heart is a promising alternative, which is non-invasive and more specific, has high spatial and temporal precision, and avoids the shortcomings in electrical stimulation. Drosophila melanogaster, which is a powerful model organism with orthologs of nearly 75% of human disease genes, has not been studied for optogenetic pacing in the heart. Here, we developed a non-invasive integrated optical pacing and optical coherence microscopy (OCM) imaging system to control the heart rhythm of Drosophila at different developmental stages using light. The OCM system is capable of providing high imaging speed (130 frames/s) and ultrahigh imaging resolutions (1.5 μm and 3.9 μm for axial and transverse resolutions, respectively). A light-sensitive pacemaker was developed in Drosophila by specifically expressing the light-gated cation channel, channelrhodopsin-2 (ChR2) in transgenic Drosophila heart. We achieved non-invasive and specific optical control of the Drosophila heart rhythm throughout the fly's life cycle (larva, pupa, and adult) by stimulating the heart with 475 nm pulsed laser light. Heart response to stimulation pulses was monitored non-invasively with OCM. This integrated non-invasive optogenetic control and in vivo imaging technique provides a novel platform for performing research studies in developmental cardiology.

  18. Pulsed Light Stimulation Increases Boundary Preference and Periodicity of Episodic Motor Activity in Drosophila melanogaster

    PubMed Central

    Qiu, Shuang; Xiao, Chengfeng; Robertson, R. Meldrum

    2016-01-01

    There is considerable interest in the therapeutic benefits of long-term sensory stimulation for improving cognitive abilities and motor performance of stroke patients. The rationale is that such stimulation would activate mechanisms of neural plasticity to promote enhanced coordination and associated circuit functions. Experimental approaches to characterize such mechanisms are needed. Drosophila melanogaster is one of the most attractive model organisms to investigate neural mechanisms responsible for stimulation-induced behaviors with its powerful accessibility to genetic analysis. In this study, the effect of chronic sensory stimulation (pulsed light stimulation) on motor activity in w1118 flies was investigated. Flies were exposed to a chronic pulsed light stimulation protocol prior to testing their performance in a standard locomotion assay. Flies responded to pulsed light stimulation with increased boundary preference and travel distance in a circular arena. In addition, pulsed light stimulation increased the power of extracellular electrical activity, leading to the enhancement of periodic electrical activity which was associated with a centrally-generated motor pattern (struggling behavior). In contrast, such periodic events were largely missing in w1118 flies without pulsed light treatment. These data suggest that the sensory stimulation induced a response in motor activity associated with the modifications of electrical activity in the central nervous system (CNS). Finally, without pulsed light treatment, the wild-type genetic background was associated with the occurrence of the periodic activity in wild-type Canton S (CS) flies, and w+ modulated the consistency of periodicity. We conclude that pulsed light stimulation modifies behavioral and electrophysiological activities in w1118 flies. These data provide a foundation for future research on the genetic mechanisms of neural plasticity underlying such behavioral modification. PMID:27684063

  19. Pulsed Light Stimulation Increases Boundary Preference and Periodicity of Episodic Motor Activity in Drosophila melanogaster.

    PubMed

    Qiu, Shuang; Xiao, Chengfeng; Robertson, R Meldrum

    There is considerable interest in the therapeutic benefits of long-term sensory stimulation for improving cognitive abilities and motor performance of stroke patients. The rationale is that such stimulation would activate mechanisms of neural plasticity to promote enhanced coordination and associated circuit functions. Experimental approaches to characterize such mechanisms are needed. Drosophila melanogaster is one of the most attractive model organisms to investigate neural mechanisms responsible for stimulation-induced behaviors with its powerful accessibility to genetic analysis. In this study, the effect of chronic sensory stimulation (pulsed light stimulation) on motor activity in w1118 flies was investigated. Flies were exposed to a chronic pulsed light stimulation protocol prior to testing their performance in a standard locomotion assay. Flies responded to pulsed light stimulation with increased boundary preference and travel distance in a circular arena. In addition, pulsed light stimulation increased the power of extracellular electrical activity, leading to the enhancement of periodic electrical activity which was associated with a centrally-generated motor pattern (struggling behavior). In contrast, such periodic events were largely missing in w1118 flies without pulsed light treatment. These data suggest that the sensory stimulation induced a response in motor activity associated with the modifications of electrical activity in the central nervous system (CNS). Finally, without pulsed light treatment, the wild-type genetic background was associated with the occurrence of the periodic activity in wild-type Canton S (CS) flies, and w+ modulated the consistency of periodicity. We conclude that pulsed light stimulation modifies behavioral and electrophysiological activities in w1118 flies. These data provide a foundation for future research on the genetic mechanisms of neural plasticity underlying such behavioral modification.

  20. Increased frequency of mitotic crossing-over in heterochromatin during the first cleavage division in Drosophila melanogaster

    SciTech Connect

    Omel`yanchuk, L.V.; Volkova, E.I.

    1995-06-01

    It is shown that, although no compaction of paracentromeric heterochromatin occurs during the first cleavage division in Drosophila melanogaster, the frequency of mitotic crossing-over in corresponding chromosome regions is increased, as compared to that in euchromatin. Because a similar situation is observed at later stages of Drosophila development, at which compact chromatin regions become well-manifested, it is concluded that the effect of heterochromatin on the frequency of crossing-over does not depend on its packing. A positive correlation between crossing-over events in paracentromeric heterochromatin and euchromatin was observed. This effect is probably due to the formation of a continuous region of somatic synapsis, which facilitates the process of mitotic crossing-over. On this basis, it is proposed that the effect of heterochromatin on mitotic crossing-over is associated with preferential chromosome pairing in the corresponding regions. 10 refs., 1 fig.

  1. Curcumin-supplemented diets increase superoxide dismutase activity and mean lifespan in Drosophila

    USDA-ARS?s Scientific Manuscript database

    Curcumin is an antioxidant extracted from the root of the turmeric plant. We examined the antioxidant effect and lifespan extension of curcumin in Drosophila. To ascertain the antioxidant effects of curcumin with regard to lifespan extension and the response to reactive oxygen species, female and ma...

  2. Supplementation with major royal jelly proteins increases lifespan, feeding and fecundity in Drosophila

    USDA-ARS?s Scientific Manuscript database

    The major royal-jelly proteins (MRJPs) are the main constituents responsible for the specific physiological role of royal jelly (RJ) in honeybees. Male and female Drosophila flies were fed diets containing either no MRJPs (A) or casein (B) at 1.25% (w/w) of diet or MRJPs at 1.25% (C), 2.50% (D), or ...

  3. Increasing the imaging depth through computational scattering correction (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Koberstein-Schwarz, Benno; Omlor, Lars; Schmitt-Manderbach, Tobias; Mappes, Timo; Ntziachristos, Vasilis

    2016-03-01

    Imaging depth is one of the most prominent limitations in light microscopy. The depth in which we are still able to resolve biological structures is limited by the scattering of light within the sample. We have developed an algorithm to compensate for the influence of scattering. The potential of algorithm is demonstrated on a 3D image stack of a zebrafish embryo captured with a selective plane illumination microscope (SPIM). With our algorithm we were able shift the point in depth, where scattering starts to blur the imaging and effect the image quality by around 30 µm. For the reconstruction the algorithm only uses information from within the image stack. Therefore the algorithm can be applied on the image data from every SPIM system without further hardware adaption. Also there is no need for multiple scans from different views to perform the reconstruction. The underlying model estimates the recorded image as a convolution between the distribution of fluorophores and a point spread function, which describes the blur due to scattering. Our algorithm performs a space-variant blind deconvolution on the image. To account for the increasing amount of scattering in deeper tissue, we introduce a new regularizer which models the increasing width of the point spread function in order to improve the image quality in the depth of the sample. Since the assumptions the algorithm is based on are not limited to SPIM images the algorithm should also be able to work on other imaging techniques which provide a 3D image volume.

  4. Cooperativity of Negative Autoregulation Confers Increased Mutational Robustness

    PubMed Central

    Marciano, David C.; Lua, Rhonald C.; Herman, Christophe; Lichtarge, Olivier

    2016-01-01

    Negative autoregulation is universally found across organisms. In the bacterium Escherichia coli, transcription factors often repress their own expression to form a negative feedback network motif that enables robustness to changes in biochemical parameters. Here we present a simple phenomenological model of a negative feedback transcription factor repressing both itself and another target gene. The strength of the negative feedback is characterized by three parameters: the cooperativity in self-repression, the maximal expression rate of the transcription factor, and the apparent dissociation constant of the transcription factor binding to its own promoter. Analysis of the model shows that the target gene levels are robust to mutations in the transcription factor, and that the robustness improves as the degree of cooperativity in self-repression increases. The prediction is tested in the LexA transcriptional network of E. coli by altering cooperativity in self-repression and promoter strength. Indeed, we find robustness is correlated with the former. Considering the proposed importance of gene regulation in speciation, parameters governing a transcription factor’s robustness to mutation may have significant influence on a cell or organism’s capacity to evolve. PMID:27391757

  5. Cooperativity of Negative Autoregulation Confers Increased Mutational Robustness

    NASA Astrophysics Data System (ADS)

    Marciano, David C.; Lua, Rhonald C.; Herman, Christophe; Lichtarge, Olivier

    2016-06-01

    Negative autoregulation is universally found across organisms. In the bacterium Escherichia coli, transcription factors often repress their own expression to form a negative feedback network motif that enables robustness to changes in biochemical parameters. Here we present a simple phenomenological model of a negative feedback transcription factor repressing both itself and another target gene. The strength of the negative feedback is characterized by three parameters: the cooperativity in self-repression, the maximal expression rate of the transcription factor, and the apparent dissociation constant of the transcription factor binding to its own promoter. Analysis of the model shows that the target gene levels are robust to mutations in the transcription factor, and that the robustness improves as the degree of cooperativity in self-repression increases. The prediction is tested in the LexA transcriptional network of E. coli by altering cooperativity in self-repression and promoter strength. Indeed, we find robustness is correlated with the former. Considering the proposed importance of gene regulation in speciation, parameters governing a transcription factor's robustness to mutation may have significant influence on a cell or organism's capacity to evolve.

  6. Dual role for Hox genes and Hox co-factors in conferring leg motoneuron survival and identity in Drosophila.

    PubMed

    Baek, Myungin; Enriquez, Jonathan; Mann, Richard S

    2013-05-01

    Adult Drosophila walk using six multi-jointed legs, each controlled by ∼50 leg motoneurons (MNs). Although MNs have stereotyped morphologies, little is known about how they are specified. Here, we describe the function of Hox genes and homothorax (hth), which encodes a Hox co-factor, in Drosophila leg MN development. Removing either Hox or Hth function from a single neuroblast (NB) lineage results in MN apoptosis. A single Hox gene, Antennapedia (Antp), is primarily responsible for MN survival in all three thoracic segments. When cell death is blocked, partially penetrant axon branching errors are observed in Hox mutant MNs. When single MNs are mutant, errors in both dendritic and axon arborizations are observed. Our data also suggest that Antp levels in post-mitotic MNs are important for specifying their identities. Thus, in addition to being essential for survival, Hox and hth are required to specify accurate MN morphologies in a level-dependent manner.

  7. The Trojan Female Technique for pest control: a candidate mitochondrial mutation confers low male fertility across diverse nuclear backgrounds in Drosophila melanogaster.

    PubMed

    Dowling, Damian K; Tompkins, Daniel M; Gemmell, Neil J

    2015-10-01

    Pest species represent a major ongoing threat to global biodiversity. Effective management approaches are required that regulate pest numbers, while minimizing collateral damage to nontarget species. The Trojan Female Technique (TFT) was recently proposed as a prospective approach to biological pest control. The TFT draws on the evolutionary hypothesis that maternally inherited mitochondrial genomes are prone to the accumulation of male, but not female, harming mutations. These mutations could be harnessed to provide trans-generational fertility-based control of pest species. A candidate TFT mutation was recently described in the fruit fly, Drosophila melanogaster, which confers male-only sterility in the specific isogenic nuclear background in which it is maintained. However, applicability of the TFT relies on mitochondrial mutations whose male-sterilizing effects are general across nuclear genomic contexts. We test this assumption, expressing the candidate TFT-mutation bearing haplotype alongside a range of nuclear backgrounds and comparing its fertility in males, relative to that of control haplotypes. We document consistently lower fertility for males harbouring the TFT mutation, in both competitive and noncompetitive mating contexts, across all nuclear backgrounds screened. This indicates that TFT mutations conferring reduced male fertility can segregate within populations and could be harnessed to facilitate this novel form of pest control.

  8. The Trojan Female Technique for pest control: a candidate mitochondrial mutation confers low male fertility across diverse nuclear backgrounds in Drosophila melanogaster

    PubMed Central

    Dowling, Damian K; Tompkins, Daniel M; Gemmell, Neil J

    2015-01-01

    Pest species represent a major ongoing threat to global biodiversity. Effective management approaches are required that regulate pest numbers, while minimizing collateral damage to nontarget species. The Trojan Female Technique (TFT) was recently proposed as a prospective approach to biological pest control. The TFT draws on the evolutionary hypothesis that maternally inherited mitochondrial genomes are prone to the accumulation of male, but not female, harming mutations. These mutations could be harnessed to provide trans-generational fertility-based control of pest species. A candidate TFT mutation was recently described in the fruit fly, Drosophila melanogaster, which confers male-only sterility in the specific isogenic nuclear background in which it is maintained. However, applicability of the TFT relies on mitochondrial mutations whose male-sterilizing effects are general across nuclear genomic contexts. We test this assumption, expressing the candidate TFT-mutation bearing haplotype alongside a range of nuclear backgrounds and comparing its fertility in males, relative to that of control haplotypes. We document consistently lower fertility for males harbouring the TFT mutation, in both competitive and noncompetitive mating contexts, across all nuclear backgrounds screened. This indicates that TFT mutations conferring reduced male fertility can segregate within populations and could be harnessed to facilitate this novel form of pest control. PMID:26495040

  9. Increasing Participation in Learning. Symposium 19. [Concurrent Symposium Session at AHRD Annual Conference, 2000.

    ERIC Educational Resources Information Center

    2000

    This document contains three papers from a symposium on increasing participation in learning that was conducted as part of a conference on human resource development (HRD). "Factors Influencing Employee Participation in Training: An Empirical Investigation" (Reid A. Bates) reports on a mediated model of employee participation in training…

  10. Using Student Conferences to Increase Participation in the Classroom: A Case Study

    ERIC Educational Resources Information Center

    Arenas, M. G.; Castillo, P. A.; de Vega, F. F.; Merelo, J. J.

    2012-01-01

    This paper describes the use of a student conference as a novel experience aimed at motivating students enrolled in various computer architecture courses, such as Microprocessor Systems. The goal was to increase student engagement, to decrease failure rates, and to introduce students to the world of research. This multidisciplinary experience…

  11. Increasing Job Satisfaction. Symposium 22. [Concurrent Symposium Session at AHRD Annual Conference, 2000.

    ERIC Educational Resources Information Center

    2000

    This document contains three papers from a symposium on increasing job satisfaction that was conducted as part of a conference on human resource development (HRD). "A Systematic Model of Job Design by Examining the Organizational Factors Affecting Satisfaction" (Zhichao Cheng, Danyang Yang, Fenglou Liu) reports on a project in which…

  12. Polyandry increases offspring viability and mother productivity but does not decrease mother survival in Drosophila pseudoobscura.

    PubMed

    Gowaty, Patricia Adair; Kim, Yong-Kyu; Rawlings, Jessica; Anderson, W W

    2010-08-03

    Polyandrous mating is common, but the benefits for females of polyandry remain controversial. To test whether mating with multiple males affects female fitness, we compared lifetime components of fitness of three experimental sets of Drosophila pseudoobscura females: monogamous females allowed to copulate one time (MOC); monogamous females held with a male over her entire life and experiencing many copulations (MMC); and polyandrous females with a different male over each day of their lives and also experiencing many copulations (PMC). Consistent with previous studies in this species, females in treatments in which multiple copulations occurred, MMC and PMC, had offspring with significantly higher egg-to-adult survival (i.e., offspring viability) and higher numbers of adult offspring (i.e., productivity) than MOC females, showing that multiple inseminations enhance offspring and mother fitness. In addition, although MMC females laid significantly more eggs than polyandrous (PMC) females, percent egg-to-adult survival and number of adult offspring were higher for PMC than MMC females, showing that polyandrous mating enhances the fitness of females more than multiply mating with only one male. Inconsistent with the cost of reproduction, lifespan was not significantly longer for MOC females than for MMC or PMC females. To our knowledge, this is the first study to examine simultaneously in outbred WT Drosophila pseudoobscura the lifetime costs and benefits to females of polyandry, monogamy with a single copulation, and monogamy with repeat copulations.

  13. Polyandry increases offspring viability and mother productivity but does not decrease mother survival in Drosophila pseudoobscura

    PubMed Central

    Gowaty, Patricia Adair; Kim, Yong-Kyu; Rawlings, Jessica; Anderson, W. W.

    2010-01-01

    Polyandrous mating is common, but the benefits for females of polyandry remain controversial. To test whether mating with multiple males affects female fitness, we compared lifetime components of fitness of three experimental sets of Drosophila pseudoobscura females: monogamous females allowed to copulate one time (MOC); monogamous females held with a male over her entire life and experiencing many copulations (MMC); and polyandrous females with a different male over each day of their lives and also experiencing many copulations (PMC). Consistent with previous studies in this species, females in treatments in which multiple copulations occurred, MMC and PMC, had offspring with significantly higher egg-to-adult survival (i.e., offspring viability) and higher numbers of adult offspring (i.e., productivity) than MOC females, showing that multiple inseminations enhance offspring and mother fitness. In addition, although MMC females laid significantly more eggs than polyandrous (PMC) females, percent egg-to-adult survival and number of adult offspring were higher for PMC than MMC females, showing that polyandrous mating enhances the fitness of females more than multiply mating with only one male. Inconsistent with the cost of reproduction, lifespan was not significantly longer for MOC females than for MMC or PMC females. To our knowledge, this is the first study to examine simultaneously in outbred WT Drosophila pseudoobscura the lifetime costs and benefits to females of polyandry, monogamy with a single copulation, and monogamy with repeat copulations. PMID:20643932

  14. High expression of Cyp6g1, a cytochrome P450 gene, does not necessarily confer DDT resistance in Drosophila melanogaster.

    PubMed

    Kuruganti, Srilalitha; Lam, Vita; Zhou, Xuguo; Bennett, Gary; Pittendrigh, Barry R; Ganguly, Ranjan

    2007-02-15

    Cytochrome P450 monooxygenases, a family of detoxifying enzymes, are thought to confer resistance to various insecticides including DDT. Daborn et al. [Daborn, P., Yen, J.L., Bogwitz, M., Le Goff, G., Feil, et al. 2002. A single p450 allele associated with insecticide resistance in Drosophila. Science 297, 2253-2256.] suggested that the Accord transposable element causes overexpression of a Cyp6g1 allele, which has spread globally and is the basis of DDT resistance in Drosophila melanogaster populations. To determine whether the same phenomenon also operates in other Drosophila strains, we investigated 91-R, 91-C, ry(506), Wisconsin, Canton-SH and Hikone-RH strains. While the LC(50) values for the 91-R and Wisconsin strains are 8348 microg and 447 microg of DDT, respectively, values for the other four strains range between 0.74 to 20.9 microg. As expected, the susceptible ry(506) and 91-C strains have about 16-33-fold lower levels of CYP6G1 mRNA than the resistant 91-R and Wisconsin strains. Surprisingly, CYP6G1 mRNA and protein levels in the Canton-SH and Hikone-RH strains are as high as in the two resistant strains, yet they are as susceptible as the 91-C strain. The susceptible phenotype of the Canton-SH and Hikone-RH strains is not due to mutation in the Cyp6g1 gene; sequence analysis showed that Cyp6g1 alleles of resistant and susceptible strains are very similar and cannot be classified into resistant and susceptible alleles. As observed by others, we also found that only the 5'-upstream DNA of overexpressing alleles of Cyp6g1 has an insertional DNA, which is similar to Accord and Ninja elements. To examine the role of Cyp6g1 in DDT resistance, we substituted the Cyp6g1 allele of the 91-R strain with the allele from the susceptible 91-C strain via recombination and synthesized three recombinant lines. All three lines lacked Accord insertion and showed low expression of Cyp6g1 like the 91-C strain, yet they were as highly resistant as the 91-R strain. We

  15. Molecular evolution under increasing transposable element burden in Drosophila: A speed limit on the evolutionary arms race

    PubMed Central

    2011-01-01

    Background Genome architecture is profoundly influenced by transposable elements (TEs), and natural selection against their harmful effects is a critical factor limiting their spread. Genome defense by the piRNA silencing pathway also plays a crucial role in limiting TE proliferation. How these two forces jointly determine TE abundance is not well understood. To shed light on the nature of factors that predict TE success, we test three distinct hypotheses in the Drosophila genus. First, we determine whether TE abundance and relaxed genome-wide purifying selection on protein sequences are positively correlated. This serves to test the hypothesis that variation in TE abundance in the Drosophila genus can be explained by the strength of natural selection, relative to drift, acting in parallel against mildly deleterious non-synonymous mutations. Second, we test whether increasing TE abundance is correlated with an increased rate of amino-acid evolution in genes encoding the piRNA machinery, as might be predicted by an evolutionary arms race model. Third, we test whether increasing TE abundance is correlated with greater codon bias in genes of the piRNA machinery. This is predicted if increasing TE abundance selects for increased efficiency in the machinery of genome defense. Results Surprisingly, we find neither of the first two hypotheses to be true. Specifically, we found that genome-wide levels of purifying selection, measured by the ratio of non-synonymous to synonymous substitution rates (ω), were greater in species with greater TE abundance. In addition, species with greater TE abundance have greater levels of purifying selection in the piRNA machinery. In contrast, it appears that increasing TE abundance has primarily driven adaptation in the piRNA machinery by increasing codon bias. Conclusions These results indicate that within the Drosophila genus, a historically reduced strength of selection relative to drift is unlikely to explain patterns of increased TE

  16. Increasing Faculty Attendance at Emergency Medicine Resident Conferences: Does CME Credit Make a Difference?

    PubMed Central

    Lefebvre, Cedric W.; Hiestand, Brian; Bond, Michael C.; Fox, Sean M.; Char, Doug; Weber, Drew S.; Glenn, David; Patterson, Leigh A.; Manthey, David E.

    2013-01-01

    Background Faculty involvement in resident teaching events is beneficial to resident education, yet evidence about the factors that promote faculty attendance at resident didactic conferences is limited. Objective To determine whether offering continuing medical education (CME) credits would result in an increase in faculty attendance at weekly emergency medicine conferences and whether faculty would report the availability of CME credit as a motivating factor. Methods Our prospective, multi-site, observational study of 5 emergency medicine residency programs collected information on the number of faculty members present at CME and non-CME lectures for 9 months and collected information from faculty on factors influencing decisions to attend resident educational events and from residents on factors influencing their learning experience. Results Lectures offering CME credit on average were attended by 5 additional faculty members per hour, compared with conferences that did not offer CME credit (95% confidence interval [CI], 3.9–6.1; P < .001). Faculty reported their desire to “participate in resident education” was the most influential factor prompting them to attend lectures, followed by “explore current trends in emergency medicine” and the lecture's “specific topic.” Faculty also reported that “clinical/administrative duties” and “family responsibilities” negatively affected their ability to attend. Residents reported that the most important positive factor influencing their conference experience was “lectures given by faculty.” Conclusions Although faculty reported that CME credit was not an important factor in their decision to attend resident conferences, offering CME credit resulted in significant increases in faculty attendance. Residents reported that “lectures given by faculty” and “faculty attendance” positively affected their learning experience. PMID:24404225

  17. Increasing Faculty Attendance at Emergency Medicine Resident Conferences: Does CME Credit Make a Difference?

    PubMed

    Lefebvre, Cedric W; Hiestand, Brian; Bond, Michael C; Fox, Sean M; Char, Doug; Weber, Drew S; Glenn, David; Patterson, Leigh A; Manthey, David E

    2013-03-01

    Faculty involvement in resident teaching events is beneficial to resident education, yet evidence about the factors that promote faculty attendance at resident didactic conferences is limited. To determine whether offering continuing medical education (CME) credits would result in an increase in faculty attendance at weekly emergency medicine conferences and whether faculty would report the availability of CME credit as a motivating factor. Our prospective, multi-site, observational study of 5 emergency medicine residency programs collected information on the number of faculty members present at CME and non-CME lectures for 9 months and collected information from faculty on factors influencing decisions to attend resident educational events and from residents on factors influencing their learning experience. Lectures offering CME credit on average were attended by 5 additional faculty members per hour, compared with conferences that did not offer CME credit (95% confidence interval [CI], 3.9-6.1; P < .001). Faculty reported their desire to "participate in resident education" was the most influential factor prompting them to attend lectures, followed by "explore current trends in emergency medicine" and the lecture's "specific topic." Faculty also reported that "clinical/administrative duties" and "family responsibilities" negatively affected their ability to attend. Residents reported that the most important positive factor influencing their conference experience was "lectures given by faculty." Although faculty reported that CME credit was not an important factor in their decision to attend resident conferences, offering CME credit resulted in significant increases in faculty attendance. Residents reported that "lectures given by faculty" and "faculty attendance" positively affected their learning experience.

  18. Methanol exposure interferes with morphological cell movements in the Drosophila embryo and causes increased apoptosis in the CNS.

    PubMed

    Mellerick, Dervla M; Liu, Heather

    2004-09-05

    Despite the significant contributions of tissue culture and bacterial models to toxicology, whole animal models for developmental neurotoxins are limited in availability and ease of experimentation. Because Drosophila is a well understood model for embryonic development that is highly accessible, we asked whether it could be used to study methanol developmental neurotoxicity. In the presence of 4% methanol, approximately 35% of embryos die and methanol exposure leads to severe CNS defects in about half those embryos, where the longitudinal connectives are dorsally displaced and commissure formation is severely reduced. In addition, a range of morphological defects in other germ layers is seen, and cell movement is adversely affected by methanol exposure. Although we did not find any evidence to suggest that methanol exposure affects the capacity of neuroblasts to divide or induces inappropriate apoptosis in these cells, in the CNS of germ band retracted embryos, the number of apoptotic nuclei is significantly increased in methanol-exposed embryos in comparison to controls, particularly in and adjacent to the ventral midline. Apoptosis contributes significantly to methanol neurotoxicity because embryos lacking the cell death genes grim, hid, and reaper have milder CNS defects resulting from methanol exposure than wild-type embryos. Our data suggest that when neurons and glia are severely adversely affected by methanol exposure, the damaged cells are cleared by apoptosis, leading to embryonic death. Thus, the Drosophila embryo may prove useful in identifying and unraveling mechanistic aspects of developmental neurotoxicity, specifically in relation to methanol toxicity.

  19. The Native Wolbachia Endosymbionts of Drosophila melanogaster and Culex quinquefasciatus Increase Host Resistance to West Nile Virus Infection

    PubMed Central

    Glaser, Robert L.; Meola, Mark A.

    2010-01-01

    Background The bacterial endosymbiont Wolbachia pipientis has been shown to increase host resistance to viral infection in native Drosophila hosts and in the normally Wolbachia-free heterologous host Aedes aegypti when infected by Wolbachia from Drosophila melanogaster or Aedes albopictus. Wolbachia infection has not yet been demonstrated to increase viral resistance in a native Wolbachia-mosquito host system. Methodology/Principal Findings In this study, we investigated Wolbachia-induced resistance to West Nile virus (WNV; Flaviviridae) by measuring infection susceptibility in Wolbachia-infected and Wolbachia-free D. melanogaster and Culex quinquefasciatus, a natural mosquito vector of WNV. Wolbachia infection of D. melanogaster induces strong resistance to WNV infection. Wolbachia-infected flies had a 500-fold higher ID50 for WNV and produced 100,000-fold lower virus titers compared to flies lacking Wolbachia. The resistance phenotype was transmitted as a maternal, cytoplasmic factor and was fully reverted in flies cured of Wolbachia. Wolbachia infection had much less effect on the susceptibility of D. melanogaster to Chikungunya (Togaviridae) and La Crosse (Bunyaviridae) viruses. Wolbachia also induces resistance to WNV infection in Cx. quinquefasciatus. While Wolbachia had no effect on the overall rate of peroral infection by WNV, Wolbachia-infected mosquitoes produced lower virus titers and had 2 to 3-fold lower rates of virus transmission compared to mosquitoes lacking Wolbachia. Conclusions/Significance This is the first demonstration that Wolbachia can increase resistance to arbovirus infection resulting in decreased virus transmission in a native Wolbachia-mosquito system. The results suggest that Wolbachia reduces vector competence in Cx. quinquefasciatus, and potentially in other Wolbachia-infected mosquito vectors. PMID:20700535

  20. Non-invasive red light optogenetic pacing and optical coherence microscopy (OCM) imaging for drosophila melanogaster (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Men, Jing; Li, Airong; Jerwick, Jason; Tanzi, Rudolph E.; Zhou, Chao

    2017-02-01

    Cardiac pacing could be a powerful tool for investigating mammalian cardiac electrical conduction systems as well as for treatment of certain cardiac pathologies. However, traditional electrical pacing using pacemaker requires an invasive surgical procedure. Electrical currents from the implanted electrodes can also cause damage to heart tissue, further restricting its utility. Optogenetic pacing has been developed as a promising, non-invasive alternative to electrical stimulation for controlling animal heart rhythms. It induces heart contractions by shining pulsed light on transgene-generated microbial opsins, which in turn activate the light gated ion channels in animal hearts. However, commonly used opsins in optogenetic pacing, such as channelrhodopsin-2 (ChR2), require short light wavelength stimulation (475 nm), which is strongly absorbed and scattered by tissue. Here, we performed optogenetic pacing by expression of recently engineered red-shifted microbial opsins, ReaChR and CsChrimson, in a well-established animal model, Drosophila melanogaster, using the 617 nm stimulation light pulses. The OCM technique enables non-invasive optical imaging of animal hearts with high speed and ultrahigh axial and transverse resolutions. We integrated a customized OCM system with the optical stimulation system to monitor the optogenetic pacing noninvasively. The use of red-sifted opsins enabled deeper penetration of simulating light at lower power, which is promising for applications of optogenetic pacing in mammalian cardiac pathology studies or clinical treatments in the future.

  1. Drosophila microRNAs 263a/b confer robustness during development by protecting nascent sense organs from apoptosis.

    PubMed

    Hilgers, Valérie; Bushati, Natascha; Cohen, Stephen M

    2010-06-15

    miR-263a/b are members of a conserved family of microRNAs that are expressed in peripheral sense organs across the animal kingdom. Here we present evidence that miR-263a and miR-263b play a role in protecting Drosophila mechanosensory bristles from apoptosis by down-regulating the pro-apoptotic gene head involution defective. Both microRNAs are expressed in the bristle progenitors, and despite a difference in their seed sequence, they share this key common target. In miR-263a and miR-263b deletion mutants, loss of bristles appears to be sporadic, suggesting that the role of the microRNAs may be to ensure robustness of the patterning process by promoting survival of these functionally specified cells. In the context of the retina, this mechanism ensures that the interommatidial bristles are protected during the developmentally programmed wave of cell death that prunes excess cells in order to refine the pattern of the pupal retina.

  2. Does increased heat resistance result in higher susceptibility to predation? A test using Drosophila melanogaster selection and hardening.

    PubMed

    Hangartner, Sandra; Dworkin, Ian; DeNieu, Michael; Hoffmann, Ary A

    2017-04-07

    Heat resistance of ectotherms can be increased both by plasticity and evolution, but these effects may have trade-offs resulting from biotic interactions. Here we test for predation costs in Drosophila melanogaster populations with altered heat resistance produced by adult hardening and directional selection for increased heat resistance. In addition, we also tested for genetic trade-offs by testing heat resistance in lines that have evolved under increased predation risk. We show that while 35/37°C hardening increases heat resistance as expected, it does not increase predation risk from jumping spiders or mantids; in fact there was an indication that survival may have increased under predation following a triple 37°C compared to a single 35°C hardening treatment. Flies that survived a 39°C selection cycle showed lower survival under predation, suggesting a predation cost of exposure to a more severe heat stress. There was however no correlated response to selection because survival did not differ between control and selected lines after selection was relaxed for one or two generations. In addition, lines selected for increased predation risk did not differ in heat resistance. Our findings suggest independent evolutionary responses to predation and heat as measured in laboratory assays, and no costs of heat hardening on susceptibility to predation. This article is protected by copyright. All rights reserved.

  3. High hemocyte load is associated with increased resistance against parasitoids in Drosophila suzukii, a relative of D. melanogaster.

    PubMed

    Kacsoh, Balint Z; Schlenke, Todd A

    2012-01-01

    Among the most common parasites of Drosophila in nature are parasitoid wasps, which lay their eggs in fly larvae and pupae. D. melanogaster larvae can mount a cellular immune response against wasp eggs, but female wasps inject venom along with their eggs to block this immune response. Genetic variation in flies for immune resistance against wasps and genetic variation in wasps for virulence against flies largely determines the outcome of any fly-wasp interaction. Interestingly, up to 90% of the variation in fly resistance against wasp parasitism has been linked to a very simple mechanism: flies with increased constitutive blood cell (hemocyte) production are more resistant. However, this relationship has not been tested for Drosophila hosts outside of the melanogaster subgroup, nor has it been tested across a diversity of parasitoid wasp species and strains. We compared hemocyte levels in two fly species from different subgroups, D. melanogaster and D. suzukii, and found that D. suzukii constitutively produces up to five times more hemocytes than D. melanogaster. Using a panel of 24 parasitoid wasp strains representing fifteen species, four families, and multiple virulence strategies, we found that D. suzukii was significantly more resistant to wasp parasitism than D. melanogaster. Thus, our data suggest that the relationship between hemocyte production and wasp resistance is general. However, at least one sympatric wasp species was a highly successful infector of D. suzukii, suggesting specialists can overcome the general resistance afforded to hosts by excessive hemocyte production. Given that D. suzukii is an emerging agricultural pest, identification of the few parasitoid wasps that successfully infect D. suzukii may have value for biocontrol.

  4. High Hemocyte Load Is Associated with Increased Resistance against Parasitoids in Drosophila suzukii, a Relative of D. melanogaster

    PubMed Central

    Kacsoh, Balint Z.; Schlenke, Todd A.

    2012-01-01

    Among the most common parasites of Drosophila in nature are parasitoid wasps, which lay their eggs in fly larvae and pupae. D. melanogaster larvae can mount a cellular immune response against wasp eggs, but female wasps inject venom along with their eggs to block this immune response. Genetic variation in flies for immune resistance against wasps and genetic variation in wasps for virulence against flies largely determines the outcome of any fly-wasp interaction. Interestingly, up to 90% of the variation in fly resistance against wasp parasitism has been linked to a very simple mechanism: flies with increased constitutive blood cell (hemocyte) production are more resistant. However, this relationship has not been tested for Drosophila hosts outside of the melanogaster subgroup, nor has it been tested across a diversity of parasitoid wasp species and strains. We compared hemocyte levels in two fly species from different subgroups, D. melanogaster and D. suzukii, and found that D. suzukii constitutively produces up to five times more hemocytes than D. melanogaster. Using a panel of 24 parasitoid wasp strains representing fifteen species, four families, and multiple virulence strategies, we found that D. suzukii was significantly more resistant to wasp parasitism than D. melanogaster. Thus, our data suggest that the relationship between hemocyte production and wasp resistance is general. However, at least one sympatric wasp species was a highly successful infector of D. suzukii, suggesting specialists can overcome the general resistance afforded to hosts by excessive hemocyte production. Given that D. suzukii is an emerging agricultural pest, identification of the few parasitoid wasps that successfully infect D. suzukii may have value for biocontrol. PMID:22529929

  5. Accord insertion in the 5' flanking region of CYP6G1 confers nicotine resistance in Drosophila melanogaster.

    PubMed

    Li, Xianchun; Bai, Sufen; Cass, Bodil N

    2012-07-01

    What has driven the sweep of the Accord retrotransposon insertion allele of CYP6G1 in the natural populations of Drosophila melanogaster is unknown. Previous studies on the DDT selection hypothesis produced conflicting data. To reexamine the DDT selection hypothesis and search for alternative explanations, we conducted a series of correlation and genetic linkage experiments with eight D. melanogaster natural populations collected from California (CM1, CM2, CM3, and CM7) and Africa (AM2, AM3, AM4, AM7). Diagnostic PCR showed that CM1, CM2, CM7, and AM3 have the Accord insertion in the CYP6G1 locus, whereas the other four strains do not. RT-PCR analysis exhibits a 100% correlation between Accord insertion and CYP6G1 overexpression. However, among the four strains with Accord-mediated CYP6G1 overexpression only CM1 and CM7 are resistant to DDT, and the other two strains (CM2 and AM3), like the four Accord-free strains, are susceptible to DDT. By contrast, all the four strains with Accord-mediated CYP6G1 overexpression are resistant to nicotine, a plant allelochemical. Genetic crosses between DDT resistant and susceptible Accord-insertion strains, as well as crosses between Accord-insertion and Accord-free strains demonstrated that Accord insertion and CYP6G1 overexpression are genetically linked to nicotine resistance rather than DDT resistance. These results suggest that naturally-occurring allelochemicals such as nicotine are the initial driving force for the worldwide prevalence of the Accord insertion allele of CYP6G1 in D. melanogaster natural populations. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Rare, Evolutionarily Unlikely Missense Substitutions in ATM Confer Increased Risk of Breast Cancer

    PubMed Central

    Tavtigian, Sean V.; Oefner, Peter J.; Babikyan, Davit; Hartmann, Anne; Healey, Sue; Le Calvez-Kelm, Florence; Lesueur, Fabienne; Byrnes, Graham B.; Chuang, Shu-Chun; Forey, Nathalie; Feuchtinger, Corinna; Gioia, Lydie; Hall, Janet; Hashibe, Mia; Herte, Barbara; McKay-Chopin, Sandrine; Thomas, Alun; Vallée, Maxime P.; Voegele, Catherine; Webb, Penelope M.; Whiteman, David C.; Sangrajrang, Suleeporn; Hopper, John L.; Southey, Melissa C.; Andrulis, Irene L.; John, Esther M.; Chenevix-Trench, Georgia

    2009-01-01

    The susceptibility gene for ataxia telangiectasia, ATM, is also an intermediate-risk breast-cancer-susceptibility gene. However, the spectrum and frequency distribution of ATM mutations that confer increased risk of breast cancer have been controversial. To assess the contribution of rare variants in this gene to risk of breast cancer, we pooled data from seven published ATM case-control mutation-screening studies, including a total of 1544 breast cancer cases and 1224 controls, with data from our own mutation screening of an additional 987 breast cancer cases and 1021 controls. Using an in silico missense-substitution analysis that provides a ranking of missense substitutions from evolutionarily most likely to least likely, we carried out analyses of protein-truncating variants, splice-junction variants, and rare missense variants. We found marginal evidence that the combination of ATM protein-truncating and splice-junction variants contribute to breast cancer risk. There was stronger evidence that a subset of rare, evolutionarily unlikely missense substitutions confer increased risk. On the basis of subset analyses, we hypothesize that rare missense substitutions falling in and around the FAT, kinase, and FATC domains of the protein may be disproportionately responsible for that risk and that a subset of these may confer higher risk than do protein-truncating variants. We conclude that a comparison between the graded distributions of missense substitutions in cases versus controls can complement analyses of truncating variants and help identify susceptibility genes and that this approach will aid interpretation of the data emerging from new sequencing technologies. PMID:19781682

  7. Selection for increased desiccation resistance in Drosophila melanogaster: Additive genetic control and correlated responses for other stresses

    SciTech Connect

    Hoffmann, A.A.; Parsons, P.A. )

    1989-08-01

    Previously we found that Drosophila melanogaster lines selected for increased desiccation resistance have lowered metabolic rate and behavioral activity levels, and show correlated responses for resistance to starvation and a toxic ethanol level. These results were consistent with a prediction that increased resistance to many environmental stresses may be genetically correlated because of a reduction in metabolic energy expenditure. Here we present experiments on the genetic basis of the selection response and extend the study of correlated responses to other stresses. The response to selection was not sex-specific and involved X-linked and autosomal genes acting additively. Activity differences contributed little to differences in desiccation resistance between selected and control lines. Selected lines had lower metabolic rates than controls in darkness when activity was inhibited. Adults from selected lines showed increased resistance to a heat shock, {sup 60}Co-gamma-radiation, and acute ethanol and acetic acid stress. The desiccation, ethanol and starvation resistance of isofemale lines set up from the F2s of a cross between one of the selected and one of the control lines were correlated. Selected and control lines did not differ in ether-extractable lipid content or in resistance to acetone, ether or a cold shock.

  8. Increased human AP endonuclease 1 level confers protection against the paternal age effect in mice

    PubMed Central

    Sanchez, Jamila R.; Reddick, Traci L.; Perez, Marissa; Centonze, Victoria E.; Mitra, Sankar; Izumi, Tadahide; McMahan, C. Alex; Walter, Christi A.

    2015-01-01

    Increased paternal age is associated with a greater risk of producing children with genetic disorders originating from de novo germline mutations. Mice mimic the human condition by displaying an age-associated increase in spontaneous mutant frequency in spermatogenic cells. The observed increase in mutant frequency appears to be associated with a decrease in the DNA repair protein, AP endonuclease1 (APEX1) and Apex1 heterozygous mice display an accelerated paternal age effect as young adults. In this study, we directly tested if APEX1 over-expression in cell lines and transgenic mice could prevent increases in mutagenesis. Cell lines with ectopic expression of APEX1 had increased APEX1 activity and lower spontaneous and induced mutations in the lacI reporter gene relative to the control. Spermatogenic cells obtained from mice transgenic for human APEX1 displayed increased APEX1 activity, were protected from the age-dependent increase in spontaneous germline mutagenesis, and exhibited increased apoptosis in the spermatogonial cell population. These results directly indicate that increases in APEX1 level confer protection against the murine paternal age effect, thus highlighting the role of APEX1 in preserving reproductive health with increasing age and in protection against genotoxin-induced mutagenesis in somatic cells. PMID:26201249

  9. Increased Selection Response in Larger Populations. I. Selection for Wing-Tip Height in Drosophila Melanogaster at Three Population Sizes

    PubMed Central

    Weber, K. E.

    1990-01-01

    The effect of population size on selection response was investigated with replicated selection lines of 40, 200 and 1000 selected parents, using Drosophila melanogaster homozygous for the mutant raised. Selection for increased wing-tip height was carried out for 55 generations, with an average selection intensity of 0.6 standard deviation. The rank order of responses in the seven individual lines was significantly in order of population size, and the variance of response among lines showed a significant effect of population size. The final mean responses (selected - controls, +/- standard errors) in the three treatments, in order of increasing population size, were 8.6 +/- 1.8 mils (three small lines), 15.1 +/- 1.3 mils (two medium lines), and 19.8 +/- 1.5 mils (two large lines). The differences between treatments seem to have emerged too rapidly to be the result of mutations, and are probably due mainly to the utilization of existing variation with greater efficiency by selection in larger populations. PMID:2116358

  10. Increased avidity for Dpp/BMP2 maintains the proliferation of progenitors-like cells in the Drosophila eye.

    PubMed

    Neto, Marta; Aguilar-Hidalgo, Daniel; Casares, Fernando

    2016-10-01

    During organ development, the progenitor state is transient, and depends on specific combinations of transcription factors and extracellular signals. Not surprisingly, abnormal maintenance of progenitor transcription factors may lead to tissue overgrowth, and the concurrence of signals from the local environment is often critical to trigger this overgrowth. Therefore, identifying specific combinations of transcription factors/signals promoting -or opposing- proliferation in progenitors is essential to understand normal development and disease. We have investigated this issue using the Drosophila eye as model. Transcription factors hth and tsh are transiently expressed in eye progenitors causing the expansion of the progenitor pool. However, if their co-expression is maintained experimentally, cell proliferation continues and differentiation is halted. Here we show that Hth+Tsh-induced tissue overgrowth requires the BMP2 Dpp and the abnormal hyperactivation of its pathway. Rather than using autocrine Dpp expression, Hth+Tsh cells increase their avidity for Dpp, produced locally, by upregulating extracellular matrix components. During normal development, Dpp represses hth and tsh ensuring that the progenitor state is transient. However, cells in which Hth+Tsh expression is forcibly maintained use Dpp to enhance their proliferation. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Increases in the evolutionary potential of upper thermal limits under warmer temperatures in two rainforest Drosophila species.

    PubMed

    van Heerwaarden, Belinda; Malmberg, Michelle; Sgrò, Carla M

    2016-02-01

    Tropical and subtropical species represent the majority of biodiversity. These species are predicted to lack the capacity to evolve higher thermal limits in response to selection imposed by climatic change. However, these assessments have relied on indirect estimates of adaptive capacity, using conditions that do not reflect environmental changes projected under climate change. Using a paternal half-sib full-sib breeding design, we estimated the additive genetic variance and narrow-sense heritability for adult upper thermal limits in two rainforest-restricted species of Drosophila reared under two thermal regimes, reflecting increases in seasonal temperature projected for the Wet Tropics of Australia and under standard laboratory conditions (constant 25°C). Estimates of additive genetic variation and narrow-sense heritability for adult heat tolerance were significantly different from zero in both species under projected summer, but not winter or constant, thermal regimes. In contrast, significant broad-sense genetic variation was apparent in all thermal regimes for egg-to-adult viability. Environment-dependent changes in the expression of genetic variation for adult upper thermal limits suggest that predicting adaptive responses to climate change will be difficult. Estimating adaptive capacity under conditions that do not reflect future environmental conditions may provide limited insight into evolutionary responses to climate change. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  12. How complexity increases in development: An analysis of the spatial-temporal dynamics of 1218 genes in Drosophila melanogaster.

    PubMed

    Salvador-Martínez, Irepan; Salazar-Ciudad, Isaac

    2015-09-15

    One of the most apparent phenomena in development is that it starts with something apparently simple and leads to something clearly complex with a specific and functional structure. At the level of gene expression it seems also clear that the embryo becomes progressively compartmentalized over time and space. However, there have not been any systematic attempts to quantify how this occurs. Here, we present a quantitative analysis of the compartmentalization and spatial complexity of gene expression in Drosophila melanogaster over developmental time by analyzing thousands of gene expression spatial patterns from FlyExpress database. We use three different mathematical measures of compartmentalization of gene expression in space. All these measures show a similar non-linear increase in compartmentalization over time, with the most dramatic change occurring from the maternal to the early gastrula stage. Transcription factors and growth factors showed an earlier compartmentalization. Finally, we partitioned the embryo space in 257 equally sized regions and clustered them depending on their expression similarity, within and between stages. This provides a global overview about the effective degree of differentiation and compartmentalization between body parts at each developmental stage and when and where in the embryo there are more changes, due to signaling or movement.

  13. A single locus confers tolerance to continuous light and allows substantial yield increase in tomato.

    PubMed

    Velez-Ramirez, Aaron I; van Ieperen, Wim; Vreugdenhil, Dick; van Poppel, Pieter M J A; Heuvelink, Ep; Millenaar, Frank F

    2014-08-05

    An important constraint for plant biomass production is the natural day length. Artificial light allows for longer photoperiods, but tomato plants develop a detrimental leaf injury when grown under continuous light--a still poorly understood phenomenon discovered in the 1920s. Here, we report a dominant locus on chromosome 7 of wild tomato species that confers continuous light tolerance. Genetic evidence, RNAseq data, silencing experiments and sequence analysis all point to the type III light harvesting chlorophyll a/b binding protein 13 (CAB-13) gene as a major factor responsible for the tolerance. In Arabidopsis thaliana, this protein is thought to have a regulatory role balancing light harvesting by photosystems I and II. Introgressing the tolerance into modern tomato hybrid lines, results in up to 20% yield increase, showing that limitations for crop productivity, caused by the adaptation of plants to the terrestrial 24-h day/night cycle, can be overcome.

  14. Increased use of Twitter at a medical conference: a report and a review of the educational opportunities.

    PubMed

    McKendrick, Douglas R A; Cumming, Grant P; Lee, Amanda J

    2012-12-11

    Most consider Twitter as a tool purely for social networking. However, it has been used extensively as a tool for online discussion at nonmedical and medical conferences, and the academic benefits of this tool have been reported. Most anesthetists still have yet to adopt this new educational tool. There is only one previously published report of the use of Twitter by anesthetists at an anesthetic conference. This paper extends that work. We report the uptake and growth in the use of Twitter, a microblogging tool, at an anesthetic conference and review the potential use of Twitter as an educational tool for anesthetists. A unique Twitter hashtag (#WSM12) was created and promoted by the organizers of the Winter Scientific Meeting held by The Association of Anaesthetists of Great Britain and Ireland (AAGBI) in London in January 2012. Twitter activity was compared with Twitter activity previously reported for the AAGBI Annual Conference (September 2011 in Edinburgh). All tweets posted were categorized according to the person making the tweet and the purpose for which they were being used. The categories were determined from a literature review. A total of 227 tweets were posted under the #WSM12 hashtag representing a 530% increase over the previously reported anesthetic conference. Sixteen people joined the Twitter stream by using this hashtag (300% increase). Excellent agreement (κ = 0.924) was seen in the classification of tweets across the 11 categories. Delegates primarily tweeted to create and disseminate notes and learning points (55%), describe which session was attended, undertake discussions, encourage speakers, and for social reasons. In addition, the conference organizers, trade exhibitors, speakers, and anesthetists who did not attend the conference all contributed to the Twitter stream. The combined total number of followers of those who actively tweeted represented a potential audience of 3603 people. This report demonstrates an increase in uptake and

  15. Near-infrared light increases ATP, extends lifespan and improves mobility in aged Drosophila melanogaster

    PubMed Central

    Begum, Rana; Calaza, Karin; Kam, Jaimie Hoh; Salt, Thomas E.; Hogg, Chris; Jeffery, Glen

    2015-01-01

    Ageing is an irreversible cellular decline partly driven by failing mitochondrial integrity. Mitochondria accumulate DNA mutations and reduce ATP production necessary for cellular metabolism. This is associated with inflammation. Near-infrared exposure increases retinal ATP in old mice via cytochrome c oxidase absorption and reduces inflammation. Here, we expose fruitflies daily to 670 nm radiation, revealing elevated ATP and reduced inflammation with age. Critically, there was a significant increase in average lifespan: 100–175% more flies survived into old age following 670 nm exposure and these had significantly improved mobility. This may be a simple route to extending lifespan and improving function in old age. PMID:25788488

  16. Near-infrared light increases ATP, extends lifespan and improves mobility in aged Drosophila melanogaster.

    PubMed

    Begum, Rana; Calaza, Karin; Kam, Jaimie Hoh; Salt, Thomas E; Hogg, Chris; Jeffery, Glen

    2015-03-01

    Ageing is an irreversible cellular decline partly driven by failing mitochondrial integrity. Mitochondria accumulate DNA mutations and reduce ATP production necessary for cellular metabolism. This is associated with inflammation. Near-infrared exposure increases retinal ATP in old mice via cytochrome c oxidase absorption and reduces inflammation. Here, we expose fruitflies daily to 670 nm radiation, revealing elevated ATP and reduced inflammation with age. Critically, there was a significant increase in average lifespan: 100-175% more flies survived into old age following 670 nm exposure and these had significantly improved mobility. This may be a simple route to extending lifespan and improving function in old age.

  17. Women in Nontraditional Jobs: A Conference Guide. Increasing Job Options for Women.

    ERIC Educational Resources Information Center

    Women's Bureau (DOL), Washington, DC.

    Designed to help organizations interested in expanding job options for women to plan and hold a community-based conference on nontraditional jobs, this guide outlines basic steps in planning, provides information about successful programs, and makes suggestions about how to deal with the mechanics of a conference. Following an introduction which…

  18. Drosophila by the dozen

    SciTech Connect

    Celniker, Susan E.; Hoskins, Roger A.

    2007-07-13

    This year's conference on Drosophila research illustratedwell the current focus of Drosophila genomics on the comprehensiveidentification of functional elements in the genome sequence, includingmRNA transcripts arising from multiple alternative start sites and splicesites, a multiplicity of noncoding transcripts and small RNAs,identification of binding sites for transcription factors, sequenceconservation in related species and sequence variation within species.Resources and technologies for genetics and functional genomics aresteadily being improved, including the building of collections oftransposon insertion mutants and hairpin constructs for RNA interference(RNAi). The conference also highlighted progress in the use of genomicinformation by many laboratories to study diverse aspects of biology andmodels of human disease. Here we will review a few highlights of especialinterest to readers of Genome Biology.

  19. Apoptotic cell death during Drosophila oogenesis is differentially increased by electromagnetic radiation depending on modulation, intensity and duration of exposure.

    PubMed

    Sagioglou, Niki E; Manta, Areti K; Giannarakis, Ioannis K; Skouroliakou, Aikaterini S; Margaritis, Lukas H

    2016-01-01

    Present generations are being repeatedly exposed to different types and doses of non-ionizing radiation (NIR) from wireless technologies (FM radio, TETRA and TV stations, GSM and UMTS phones/base stations, Wi-Fi networks, DECT phones). Although there is controversy on the published data regarding the non-thermal effects of NIR, studies have convincingly demonstrated bioeffects. Their results indicate that modulation, intensity, exposure duration and model system are important factors determining the biological response to irradiation. Attempting to address the dependence of NIR bioeffectiveness on these factors, apoptosis in the model biological system Drosophila melanogaster was studied under different exposure protocols. A signal generator was used operating alternatively under Continuous Wave (CW) or Frequency Modulation (FM) emission modes, at three power output values (10 dB, 0, -10 dB), under four carrier frequencies (100, 395, 682, 900 MHz). Newly emerged flies were exposed either acutely (6 min or 60 min on the 6th day), or repeatedly (6 min or 60 min daily for the first 6 days of their life). All exposure protocols resulted in an increase of apoptotic cell death (ACD) observed in egg chambers, even at very low electric field strengths. FM waves seem to have a stronger effect in ACD than continuous waves. Regarding intensity and temporal exposure pattern, EMF-biological tissue interaction is not linear in response. Intensity threshold for the induction of biological effects depends on frequency, modulation and temporal exposure pattern with unknown so far mechanisms. Given this complexity, translating such experimental data into possible human exposure guidelines is yet arbitrary.

  20. Male sexual behaviour and ethanol consumption from an evolutionary perspective: A comment on "Sexual Deprivation Increases Ethanol Intake in Drosophila".

    PubMed

    Guevara-Fiore, Palestina; Endler, John A

    2014-01-01

    Shohat-Ophir et al. (1) demonstrate a connection between sexual behaviour and ethanol consumption in male Drosophila flies, and how the neuropeptide F system regulates ethanol preference. Their results are rightly discussed only in a physiological context, but this has facilitated erroneous anthropomorphic interpretations by the media. Here we discuss the link between male sexual behaviour and ethanol consumption from an evolutionary perspective, providing a broader context to interpret their results.

  1. Increased Use of Twitter at a Medical Conference: A Report and a Review of the Educational Opportunities

    PubMed Central

    Cumming, Grant P; Lee, Amanda J

    2012-01-01

    Background Most consider Twitter as a tool purely for social networking. However, it has been used extensively as a tool for online discussion at nonmedical and medical conferences, and the academic benefits of this tool have been reported. Most anesthetists still have yet to adopt this new educational tool. There is only one previously published report of the use of Twitter by anesthetists at an anesthetic conference. This paper extends that work. Objective We report the uptake and growth in the use of Twitter, a microblogging tool, at an anesthetic conference and review the potential use of Twitter as an educational tool for anesthetists. Methods A unique Twitter hashtag (#WSM12) was created and promoted by the organizers of the Winter Scientific Meeting held by The Association of Anaesthetists of Great Britain and Ireland (AAGBI) in London in January 2012. Twitter activity was compared with Twitter activity previously reported for the AAGBI Annual Conference (September 2011 in Edinburgh). All tweets posted were categorized according to the person making the tweet and the purpose for which they were being used. The categories were determined from a literature review. Results A total of 227 tweets were posted under the #WSM12 hashtag representing a 530% increase over the previously reported anesthetic conference. Sixteen people joined the Twitter stream by using this hashtag (300% increase). Excellent agreement (κ = 0.924) was seen in the classification of tweets across the 11 categories. Delegates primarily tweeted to create and disseminate notes and learning points (55%), describe which session was attended, undertake discussions, encourage speakers, and for social reasons. In addition, the conference organizers, trade exhibitors, speakers, and anesthetists who did not attend the conference all contributed to the Twitter stream. The combined total number of followers of those who actively tweeted represented a potential audience of 3603 people. Conclusions This

  2. Minocycline increases the life span and motor activity and decreases lipid peroxidation in manganese treated Drosophila melanogaster.

    PubMed

    Bonilla, E; Contreras, R; Medina-Leendertz, S; Mora, M; Villalobos, V; Bravo, Y

    2012-03-29

    The objective of this study was to investigate the effect of Minocycline in the life span, motor activity, and lipid peroxidation of Drosophila melanogaster treated with manganese. Two days after emerging from the pupa male wild-type D. melanogaster were fed for 13 days with corn media containing 15 mM manganese. Then, they were divided in six groups of 300 flies each: group (a) remained treated with manganese (Mn group); group (b) began treatment with Minocycline (0.05 mM) (Mn-Minocycline group); group (c) received no additional treatment (Mn-no treatment group); group (d) simultaneously fed with manganese and Minocycline (Mn+Minocycline group). Additionally, a control (group e) with no treatment and another group (f) fed only with Minocycline after emerging from the pupa were added. All the manganese treated flies (group a) were dead on the 25th day. The life span in group f (101.66±1.33 days, mean S.E.M.) and of group b (97.00±3.46 days) were similar, but in both cases it was significantly higher than in group e (68.33±1.76 days), group c (67.05±2.30 days) and in those of group d (37.33±0.88). Manganese (groups a and d) decreased motor activity in D. melanogaster. In the Minocycline fed flies (groups b and f) a higher motor activity was detected. In Mn-Minocycline and Mn+Minocycline treated flies a significant decrease of MDA levels was detected when compared to the Minocycline group indicating that Minocycline and Mn appear to have a synergistic effect. In conclusion, Minocycline increased the life span and motor activity and decreased MDA formation of manganese treated D. melanogaster, probably by an inhibition of the production of reactive oxygen species. Manganese also exerted an antioxidant effect as shown by the significant decrease of MDA levels when compared to control flies.

  3. HLA-DR6 association confers increased resistance to T. rubrum onychomycosis in Mexican Mestizos.

    PubMed

    Asz-Sigall, Daniel; López-García, Lirio; Vega-Memije, María Elisa; Lacy-Niebla, Rosa María; García-Corona, Cristina; Ramírez-Rentería, Claudia; Granados, Julio; Villa, Antonio; Ameen, Mahreen; Arenas, Roberto

    2010-12-01

    Onychomycosis is multifactorial in origin. Studies have suggested an autosomal dominant pattern of inheritance and human leukocyte antigen DR4 (HLA-DR4) has been shown to protect against onychomycosis in an Ashkenazi Jewish population. This study investigates HLA class II association in a Mexican Mestizo population with Trichophyton rubrum onychomycosis. This was a prospective case-control study. Mexican Mestizos with a clinical diagnosis of onychomycosis and culture positive for T. rubrum were recruited, together with age- and sex-matched controls. First-degree relatives were also investigated for onychomycosis. Case-control samples were HLA typed by polymerase chain reaction sequence-specific primer based analysis. Twenty-one cases and 42 controls were recruited with a mean age of 40 years (range: 18-58 years). HLA-DR6 was found in seven (33%) cases and 19 (45%) controls [P < 0.023, odds ratio (OR) = 0.088, 95% confidence interval (CI): 0.01-0.71]. Six (29%) cases and three (7%) controls had an affected child (P < 0.043, OR = 9.15, 95% CI: 1.07-78.31), and 13 (62%) cases and 12 (29%) controls had an affected first-degree relative (P < 0.02, OR = 4.0, 95% CI: 1.1-14.3). These results suggest that HLA-DR6 confers protection against the development of onychomycosis in a Mexican Mestizo population. Having an affected first-degree relative significantly increases the risk of onychomycosis, suggesting genetic susceptibility. © 2010 The International Society of Dermatology.

  4. VEGF Promoter Polymorphism Confers an Increased Risk of Pulmonary Arterial Hypertension in a Chinese Population

    PubMed Central

    Zeng, Qingchun; Zhang, Peng; Li, Guoyang; Xie, Qiang; Cheng, Ying

    2017-01-01

    Purpose Evidence on the contribution of genes to the hereditary predisposition to pulmonary arterial hypertension (PAH) is limited. Materials and Methods In this study, we hypothesized that single nucleotide variants in vascular endothelial growth factor (VEGF) gene may alter gene function and expression and may be associated with PAH risk. Five putatively functional loci (rs699947C>A and rs833061T>C in the promoter, rs3025040C>T, rs10434G>A and rs3025053G>A in the 3'-UTR) in the VEGF gene were genotyped and analyzed in a retrospective study of 587 patients with PAH and 736 healthy subjects from southern China. Results We found that the rs833061T>C polymorphism was significantly associated with PAH risk, while the other single nucleotide polymorphisms were not. Compared to carriers with TT genotype, those with rs833061C variant genotype (CT/CC) had an increased risk of PAH (odds ratio=1.47, 95% confidence interval=1.18–1.83, p=0.001). Functional assays indicated that CT/CC variant genotype had significantly higher mRNA levels of VEGF in peripheral blood mononuclear cells than TT genotype (p=0.021). Luciferase reporter assay indicated that having a C allele conferred a significantly higher transcription activity than that with a T allele. Conclusion Our findings suggest that the functional polymorphism rs833061T>C in VEGF gene promoter modulates VEGF expression and may be a valuable biomarker for predicting PAH susceptibility. PMID:28120560

  5. Expression of human uncoupling protein-3 in Drosophila insulin-producing cells increases insulin-like peptide (DILP) levels and shortens lifespan.

    PubMed

    Humphrey, Dickon M; Toivonen, Janne M; Giannakou, Maria; Partridge, Linda; Brand, Martin D

    2009-05-01

    Uncoupling proteins (UCPs) can dissipate mitochondrial protonmotive force by increasing the proton conductance of the inner membrane and through this effect could decrease ROS production, ameliorate oxidative stress and extend lifespan. We investigated whether ubiquitous, pan-neuronal or neurosecretory cell-specific expression of human UCP3 (hUCP3) in adult Drosophila melanogaster affected lifespan. Low, ubiquitous expression of hUCP3 at levels found in rodent skeletal muscle mitochondria did not affect proton conductance in mitochondria isolated from whole flies, but high pan-neuronal expression of hUCP3 increased the proton conductance of mitochondria isolated from fly heads. Expression of hUCP3 at moderate levels in adult neurons led to a marginal lifespan-extension in males. However, high expression of hUCP3 in neuronal tissue shortened lifespan. The life-shortening effect was replicated when hUCP3 was expressed specifically in median neurosecretory cells (mNSC), which express three of the Drosophila insulin-like peptides (DILPs). Expression of hUCP3 in the mNSC did not alter expression of dilp2, dilp3 or dilp5 mRNA, but led to increased amounts of DILP2 in fly heads. These data suggest that lowering mitochondrial coupling by high expression of hUCP3 alters mNSC function in a way that appears to increase DILP-levels in fly heads and lead to a concomitant decrease in lifespan.

  6. Male killing Spiroplasma protects Drosophila melanogaster against two parasitoid wasps

    PubMed Central

    Xie, J; Butler, S; Sanchez, G; Mateos, M

    2014-01-01

    Maternally transmitted associations between endosymbiotic bacteria and insects are diverse and widespread in nature. Owing to imperfect vertical transmission, many heritable microbes have evolved compensational mechanisms to enhance their persistence in host lineages, such as manipulating host reproduction and conferring fitness benefits to host. Symbiont-mediated defense against natural enemies of hosts is increasingly recognized as an important mechanism by which endosymbionts enhance host fitness. Members of the genus Spiroplasma associated with distantly related Drosophila hosts are known to engage in either reproductive parasitism (i.e., male killing) or defense against natural enemies (the parasitic wasp Leptopilina heterotoma and a nematode). A male-killing strain of Spiroplasma (strain Melanogaster Sex Ratio Organism (MSRO)) co-occurs with Wolbachia (strain wMel) in certain wild populations of the model organism Drosophila melanogaster. We examined the effects of Spiroplasma MSRO and Wolbachia wMel on Drosophila survival against parasitism by two common wasps, Leptopilina heterotoma and Leptopilina boulardi, that differ in their host ranges and host evasion strategies. The results indicate that Spiroplasma MSRO prevents successful development of both wasps, and confers a small, albeit significant, increase in larva-to-adult survival of flies subjected to wasp attacks. We modeled the conditions under which defense can contribute to Spiroplasma persistence. Wolbachia also confers a weak, but significant, survival advantage to flies attacked by L. heterotoma. The host protective effects exhibited by Spiroplasma and Wolbachia are additive and may provide the conditions for such cotransmitted symbionts to become mutualists. Occurrence of Spiroplasma-mediated protection against distinct parasitoids in divergent Drosophila hosts suggests a general protection mechanism. PMID:24281548

  7. Male killing Spiroplasma protects Drosophila melanogaster against two parasitoid wasps.

    PubMed

    Xie, J; Butler, S; Sanchez, G; Mateos, M

    2014-04-01

    Maternally transmitted associations between endosymbiotic bacteria and insects are diverse and widespread in nature. Owing to imperfect vertical transmission, many heritable microbes have evolved compensational mechanisms to enhance their persistence in host lineages, such as manipulating host reproduction and conferring fitness benefits to host. Symbiont-mediated defense against natural enemies of hosts is increasingly recognized as an important mechanism by which endosymbionts enhance host fitness. Members of the genus Spiroplasma associated with distantly related Drosophila hosts are known to engage in either reproductive parasitism (i.e., male killing) or defense against natural enemies (the parasitic wasp Leptopilina heterotoma and a nematode). A male-killing strain of Spiroplasma (strain Melanogaster Sex Ratio Organism (MSRO)) co-occurs with Wolbachia (strain wMel) in certain wild populations of the model organism Drosophila melanogaster. We examined the effects of Spiroplasma MSRO and Wolbachia wMel on Drosophila survival against parasitism by two common wasps, Leptopilina heterotoma and Leptopilina boulardi, that differ in their host ranges and host evasion strategies. The results indicate that Spiroplasma MSRO prevents successful development of both wasps, and confers a small, albeit significant, increase in larva-to-adult survival of flies subjected to wasp attacks. We modeled the conditions under which defense can contribute to Spiroplasma persistence. Wolbachia also confers a weak, but significant, survival advantage to flies attacked by L. heterotoma. The host protective effects exhibited by Spiroplasma and Wolbachia are additive and may provide the conditions for such cotransmitted symbionts to become mutualists. Occurrence of Spiroplasma-mediated protection against distinct parasitoids in divergent Drosophila hosts suggests a general protection mechanism.

  8. Increase in the mitotic recombination frequency in Drosophila melanogaster by magnetic field exposure and its suppression by vitamin E supplement.

    PubMed

    Koana, T; Okada, M O; Ikehata, M; Nakagawa, M

    1997-01-03

    In order to estimate possible mutagenic and/or carcinogenic activity of electromagnetic fields, wing spot tests were performed in Drosophila melanogaster. A DNA repair defective mutation mei-41D5 was introduced into the conventional mwh/flr test system to enhance mutant spot frequency. Third instar larvae were exposed to a 5-Tesla static magnetic field for 24 h, and after molting, wings were examined under a microscope to detect hair spots with mutant morphology. The exposure caused a statistically significant enhancement of somatic recombination compared with the unexposed control. This enhancement was suppressed to the control level by supplement of vitamin E, a non-specific antioxidant. It is inferred that the magnetic field enhanced the genotoxic effect of spontaneously produced free radicals, possibly by affecting the lifetime of the radicals. Enhancement of non-disjunction, terminal deletions and gene mutations were not detected.

  9. Evidence that low concentrations of chlorophyllin (CHLN) increase the genetic damage induced by gamma rays in somatic cells of Drosophila.

    PubMed

    Cruces, M P; Pimentel, E; Zimmering, S

    2009-01-01

    It was first demonstrated in Salmonella that higher and lower concentrations of chlorophyllin (CHLN) may have effects in opposite directions, higher doses inhibiting and lower doses promoting the mutagenic activity of certain tobacco-related nitrosamines. Previous work of our group demonstrated that CHLN may have both a promoter and an inhibitory effect on mutagenesis in Drosophila. The present paper reviews the evidence obtained in our laboratory using gamma rays as the mutagenic agent, that higher and lower pretreatment concentrations of CHLN are associated with inhibitory and promoting effects, respectively, as in Salmonella. Employing the wing spot test, 48h larvae were pretreated with various concentrations of CHLN from 0 to 69 mM and then treated with 10 Gy gamma rays. With the highest concentration of CHLN, an approximate 54% reduction in mutagenesis was observed. At 35 mM a remnant of this inhibitory effect was found in that a significant decrease was limited to the twin spot category. Evidence of promotion was first seen at 4.3mM CHLN, an effect which persisted for the remaining five lower concentrations, the most pronounced evidence of promotion being found at the four lowest concentrations, 0.03-1.1 mM CHLN. It should be noted that no evidence of genotoxicity was found for CHLN alone, an observation consistent with the several reports in the literature. The results are taken as strong evidence that pretreatment with low concentrations of CHLN promotes DNA damage induced by gamma rays in somatic cells of Drosophila.

  10. Mio/dChREBP coordinately increases fat mass by regulating lipid synthesis and feeding behavior in Drosophila.

    PubMed

    Sassu, Eric D; McDermott, Jacqueline E; Keys, Brendan J; Esmaeili, Melody; Keene, Alex C; Birnbaum, Morris J; DiAngelo, Justin R

    2012-09-14

    During nutrient excess, triglycerides are synthesized and stored to provide energy during times of famine. The presence of high glucose leads to the activation of carbohydrate response element binding protein (ChREBP), a transcription factor that induces the expression of a number of glycolytic and lipogenic enzymes. ChREBP is expressed in major metabolic tissues and while we have a basic understanding of ChREBP function in liver, in vivo genetic systems to study the function of ChREBP in other tissues are lacking. In this study, we characterized the role of the Drosophila homolog of ChREBP, Mlx interactor (Mio), in controlling fat accumulation in larvae and adult flies. In Mio mutants, high sugar-induced lipogenic enzyme mRNA expression is blunted and lowering Mio levels specifically in the fat body using RNA interference leads to a lean phenotype. A lean phenotype is also observed when the gene bigmax, the fly homolog of ChREBP's binding partner Mlx, is decreased in the larval fat body. Interestingly, depleting Mio in the fat body results in decreased feeding providing a potential cause of the lowered triglycerides observed in these animals. However, Mio does not seem to function as a general regulator of hunger-induced behaviors as decreasing fat body Mio levels has no effect on sleep under fed or starved conditions. Together, these data implicate a role for Mio in controlling fat accumulation in Drosophila and suggests that it may act as a nutrient sensor in the fat body to coordinate feeding behavior with nutrient availability. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Increasing intracellular trehalose is sufficient to confer desiccation tolerance to Saccharomyces cerevisiae.

    PubMed

    Tapia, Hugo; Young, Lindsey; Fox, Douglas; Bertozzi, Carolyn R; Koshland, Douglas

    2015-05-12

    Diverse organisms capable of surviving desiccation, termed anhydrobiotes, include species from bacteria, yeast, plants, and invertebrates. However, most organisms are sensitive to desiccation, likely due to an assortment of different stresses such as protein misfolding and aggregation, hyperosmotic stress, membrane fracturing, and changes in cell volume and shape leading to an overcrowded cytoplasm and metabolic arrest. The exact stress(es) that cause lethality in desiccation-sensitive organisms and how the lethal stresses are mitigated in desiccation-tolerant organisms remain poorly understood. The presence of trehalose in anhydrobiotes has been strongly correlated with desiccation tolerance. In the yeast Saccharomyces cerevisiae, trehalose is essential for survival after long-term desiccation. Here, we establish that the elevation of intracellular trehalose in dividing yeast by its import from the media converts yeast from extreme desiccation sensitivity to a high level of desiccation tolerance. This trehalose-induced tolerance is independent of utilization of trehalose as an energy source, de novo synthesis of other stress effectors, or the metabolic effects of trehalose biosynthetic intermediates, indicating that a chemical property of trehalose is directly responsible for desiccation tolerance. Finally, we demonstrate that elevated intracellular maltose can also make dividing yeast tolerant to short-term desiccation, indicating that other disaccharides have stress effector activity. However, trehalose is much more effective than maltose at conferring tolerance to long-term desiccation. The effectiveness and sufficiency of trehalose as an antagonizer of desiccation-induced damage in yeast emphasizes its potential to confer desiccation tolerance to otherwise sensitive organisms.

  12. Increasing intracellular trehalose is sufficient to confer desiccation tolerance to Saccharomyces cerevisiae

    PubMed Central

    Tapia, Hugo; Young, Lindsey; Fox, Douglas; Bertozzi, Carolyn R.; Koshland, Douglas

    2015-01-01

    Diverse organisms capable of surviving desiccation, termed anhydrobiotes, include species from bacteria, yeast, plants, and invertebrates. However, most organisms are sensitive to desiccation, likely due to an assortment of different stresses such as protein misfolding and aggregation, hyperosmotic stress, membrane fracturing, and changes in cell volume and shape leading to an overcrowded cytoplasm and metabolic arrest. The exact stress(es) that cause lethality in desiccation-sensitive organisms and how the lethal stresses are mitigated in desiccation-tolerant organisms remain poorly understood. The presence of trehalose in anhydrobiotes has been strongly correlated with desiccation tolerance. In the yeast Saccharomyces cerevisiae, trehalose is essential for survival after long-term desiccation. Here, we establish that the elevation of intracellular trehalose in dividing yeast by its import from the media converts yeast from extreme desiccation sensitivity to a high level of desiccation tolerance. This trehalose-induced tolerance is independent of utilization of trehalose as an energy source, de novo synthesis of other stress effectors, or the metabolic effects of trehalose biosynthetic intermediates, indicating that a chemical property of trehalose is directly responsible for desiccation tolerance. Finally, we demonstrate that elevated intracellular maltose can also make dividing yeast tolerant to short-term desiccation, indicating that other disaccharides have stress effector activity. However, trehalose is much more effective than maltose at conferring tolerance to long-term desiccation. The effectiveness and sufficiency of trehalose as an antagonizer of desiccation-induced damage in yeast emphasizes its potential to confer desiccation tolerance to otherwise sensitive organisms. PMID:25918381

  13. Molecular evidence for increased regulatory conservation during metamorphosis, and against deleterious cascading effects of hybrid breakdown in Drosophila

    PubMed Central

    2010-01-01

    Background Speculation regarding the importance of changes in gene regulation in determining major phylogenetic patterns continues to accrue, despite a lack of broad-scale comparative studies examining how patterns of gene expression vary during development. Comparative transcriptional profiling of adult interspecific hybrids and their parental species has uncovered widespread divergence of the mechanisms controlling gene regulation, revealing incompatibilities that are masked in comparisons between the pure species. However, this has prompted the suggestion that misexpression in adult hybrids results from the downstream cascading effects of a subset of genes improperly regulated in early development. Results We sought to determine how gene expression diverges over development, as well as test the cascade hypothesis, by profiling expression in males of Drosophila melanogaster, D. sechellia, and D. simulans, as well as the D. simulans (♀) × D. sechellia (♂) male F1 hybrids, at four different developmental time points (3rd instar larval, early pupal, late pupal, and newly-emerged adult). Contrary to the cascade model of misexpression, we find that there is considerable stage-specific autonomy of regulatory breakdown in hybrids, with the larval and adult stages showing significantly more hybrid misexpression as compared to the pupal stage. However, comparisons between pure species indicate that genes expressed during earlier stages of development tend to be more conserved in terms of their level of expression than those expressed during later stages, suggesting that while Von Baer's famous law applies at both the level of nucleotide sequence and expression, it may not apply necessarily to the underlying overall regulatory network, which appears to diverge over the course of ontogeny and which can only be ascertained by combining divergent genomes in species hybrids. Conclusion Our results suggest that complex integration of regulatory circuits during

  14. Wolbachia-mediated protection against viruses in the invasive pest Drosophila suzukii.

    PubMed

    Cattel, J; Martinez, J; Jiggins, F; Mouton, L; Gibert, P

    2016-10-01

    The maternally inherited bacterium Wolbachia is well known for spreading in natural populations by manipulating the reproduction of its arthropod hosts, but can also have mutualist effects that increase host fitness. In mosquitoes and Drosophila some Wolbachia strains can lead to an increase in survival of virus-infected insects, and in most cases this is associated with reduced accumulation of the virus in host tissues. We investigated if the Wolbachia strain wSuz, which naturally infects Drosophila suzukii, is able to confer protection against Drosophila C virus and Flock House virus in different host genetic backgrounds. We found that this strain can increase host survival upon infection with these two viruses. In some cases this effect was associated with lower viral titres, suggesting that it confers resistance to the viruses rather than allowing the flies to tolerate infection. Our results indicate that, in D. suzukii, the antiviral protection provided by Wolbachia is not correlated to its density as found in other Drosophila species. This study demonstrates a phenotypic effect induced by wSuz on its native host which could explain its maintenance in natural populations of D. suzukii. © 2016 The Royal Entomological Society.

  15. Increased Variation in Adh Enzyme Activity in Drosophila Mutation-Accumulation Experiment Is Not Due to Transposable Elements at the Adh Structural Gene

    PubMed Central

    Aquadro, C. F.; Tachida, H.; Langley, C. H.; Harada, K.; Mukai, T.

    1990-01-01

    We present here a molecular analysis of the region surrounding the structural gene encoding alcohol dehydrogenase (Adh) in 47 lines of Drosophila melanogaster that have each accumulated mutations for 300 generations. While these lines show a significant increase in variation of alcohol dehydrogenase enzyme activity compared to control lines, we found no restriction map variation in a 13-kb region including the complete Adh structural gene and roughly 5 kb of both 5' and 3' sequences. Thus, the rapid accumulation of ADH activity variation after 28,200 allele generations does not appear to have been due to the mobilization of transposable elements into or out of the Adh structural gene region. PMID:1963870

  16. PSCA gene variants (rs2294008 and rs2978974) confer increased susceptibility of gallbladder carcinoma in females.

    PubMed

    Rai, Rajani; Sharma, Kiran L; Misra, Sanjeev; Kumar, Ashok; Mittal, Balraj

    2013-11-10

    PSCA is a tissue specific tumor suppressor or oncogene which has been found to be associated with several human tumors including gallbladder cancer. It is considered to be involved in the cell-proliferation inhibition and/or cell-death induction activity. Therefore, we aimed to investigate the role of PSCA gene polymorphisms in gallbladder cancer risk in North Indian population. A total of 405 gallbladder cancer patients and 247 healthy controls were included in the case-control study for risk prediction. We examined the association of two functional SNPs, rs2294008 and rs2978974 in PSCA gene by genotyping using Taqman allelic discrimination assays. Statistical analysis was done using SPSS software, version 17. Linkage disequilibrium and haplotype analysis was done with the help of SNPstats software. FDR test was used to correct for multiple comparisons. No significant associations of rs2294008 and rs2978974 genetic variants of the PSCA gene were found with GBC risk at allele, genotype or haplotype levels. Stratifying the subjects on the basis of gallstone also did not show any significant result. However, on gender stratification, we found a significant association of Trs2294008-Grs2978974 haplotype with higher risk of GBC in females (FDR Pcorr=0.021, OR=1.6). In contrary, Trs2294008-A rs2978974 haplotype conferred significant lower risk in males (FDR Pcorr=0.013; OR=0.25). These findings suggest that PSCA genetic variants may have a significant effect on GBC susceptibility in a gender specific manner. © 2013.

  17. Increased Artemis levels confer radioresistance to both high and low LET radiation exposures.

    PubMed

    Sridharan, Deepa M; Whalen, Mary K; Almendrala, Donna; Cucinotta, Francis A; Kawahara, Misako; Yannone, Steven M; Pluth, Janice M

    2012-06-19

    Artemis has a defined role in V(D)J recombination and has been implicated in the repair of radiation induced double-strand breaks. However the exact function(s) of Artemis in DNA repair and its preferred substrate(s) in vivo remain undefined. Our previous work suggests that Artemis is important for the repair of complex DNA damage like that inflicted by high Linear Energy Transfer (LET) radiation. To establish the contribution of Artemis in repairing DNA damage caused by various radiation qualities, we evaluated the effect of over-expressing Artemis on cell survival, DNA repair, and cell cycle arrest after exposure to high and low LET radiation. Our data reveal that Artemis over-expression confers marked radioprotection against both types of radiation, although the radioprotective effect was greater following high LET radiation. Inhibitor studies reveal that the radioprotection imparted by Artemis is primarily dependent on DNA-PK activity, and to a lesser extent on ATM kinase activity. Together, these data suggest a DNA-PK dependent role for Artemis in the repair of complex DNA damage. These findings indicate that Artemis levels significantly influence radiation toxicity in human cells and suggest that Artemis inhibition could be a practical target for adjuvant cancer therapies.

  18. Increased Artemis levels confer radioresistance to both high and low LET radiation exposures

    PubMed Central

    2012-01-01

    Background Artemis has a defined role in V(D)J recombination and has been implicated in the repair of radiation induced double-strand breaks. However the exact function(s) of Artemis in DNA repair and its preferred substrate(s) in vivo remain undefined. Our previous work suggests that Artemis is important for the repair of complex DNA damage like that inflicted by high Linear Energy Transfer (LET) radiation. To establish the contribution of Artemis in repairing DNA damage caused by various radiation qualities, we evaluated the effect of over-expressing Artemis on cell survival, DNA repair, and cell cycle arrest after exposure to high and low LET radiation. Results Our data reveal that Artemis over-expression confers marked radioprotection against both types of radiation, although the radioprotective effect was greater following high LET radiation. Inhibitor studies reveal that the radioprotection imparted by Artemis is primarily dependent on DNA-PK activity, and to a lesser extent on ATM kinase activity. Together, these data suggest a DNA-PK dependent role for Artemis in the repair of complex DNA damage. Conclusions These findings indicate that Artemis levels significantly influence radiation toxicity in human cells and suggest that Artemis inhibition could be a practical target for adjuvant cancer therapies. PMID:22713703

  19. Drosophila Ube3a regulates monoamine synthesis by increasing GTP cyclohydrolase I activity via a non-ubiquitin ligase mechanism

    PubMed Central

    Ferdousy, Faiza; Bodeen, William; Summers, Kyle; Doherty, Olugbenga; Wright, O'Neil; Elsisi, Nahed; Hilliard, George; O'Donnell, Janis M.; Reiter, Lawrence T.

    2010-01-01

    The underlying defects in Angelman syndrome (AS) and autism spectrum disorder (ASD) may be in part due to basic defects in synaptic plasticity and function. In some individuals serotonin reuptake inhibitors, which decrease pre-synaptic re-uptake of serotonin, can ameliorate symptoms, as can resperidone, which blocks both dopamine and serotonin receptors. Loss of maternal UBE3A expression causes AS, while maternal duplications of chromosome 15q11.2-q13 that include the UBE3A gene cause ASD, implicating the maternally expressed UBE3A gene in the ASD phenotype. In a Drosophila screen for proteins regulated by UBE3A, we identified a key regulator of monoamine synthesis, the gene Punch, or GCH1, encoding the enzyme GTP cyclohydrolase I. Here we show that Dube3a, the fly UBE3A ortholog, regulates Punch/GCH1 in the fly brain. Over-expression of Dube3a elevates tetrahydrobiopterin (THB), the rate-limiting cofactor in monoamine synthesis while loss of Dube3a has the opposite effect. The fluctuations in dopamine levels were associated with hyper- and hypoactivity, respectively, in flies. We show that changes in Punch/GCH1 and dopamine levels do not depend on the ubiquitin ligase catalytic domain of Dube3a. In addition, both wild type Dube3a and a ubiquitination-defective Dube3a-C/A form were found at high levels in nuclear fractions and appear to be poly-ubiquitinated in vivo by endogenous Dube3a. We propose that the transcriptional co-activation function of Dube3a may regulate GCH1 activity in the brain. These results provide a connection between monoamine synthesis (dopamine/serotonin) and Dube3a expression that may explain why some individuals with ASD or AS respond better to selective serotonin reuptake inhibitors than others. PMID:21147225

  20. Drosophila Ube3a regulates monoamine synthesis by increasing GTP cyclohydrolase I activity via a non-ubiquitin ligase mechanism.

    PubMed

    Ferdousy, Faiza; Bodeen, William; Summers, Kyle; Doherty, Olugbenga; Wright, O'Neil; Elsisi, Nahed; Hilliard, George; O'Donnell, Janis M; Reiter, Lawrence T

    2011-03-01

    The underlying defects in Angelman syndrome (AS) and autism spectrum disorder (ASD) may be in part due to basic defects in synaptic plasticity and function. In some individuals serotonin reuptake inhibitors, which decrease pre-synaptic re-uptake of serotonin, can ameliorate symptoms, as can resperidone, which blocks both dopamine and serotonin receptors. Loss of maternal UBE3A expression causes AS, while maternal duplications of chromosome 15q11.2-q13 that include the UBE3A gene cause ASD, implicating the maternally expressed UBE3A gene in the ASD phenotype. In a Drosophila screen for proteins regulated by UBE3A, we identified a key regulator of monoamine synthesis, the gene Punch, or GCH1, encoding the enzyme GTP cyclohydrolase I. Here we show that Dube3a, the fly UBE3A orthologue, regulates Punch/GCH1 in the fly brain. Over-expression of Dube3a elevates tetrahydrobiopterin (THB), the rate-limiting cofactor in monoamine synthesis while loss of Dube3a has the opposite effect. The fluctuations in dopamine levels were associated with hyper- and hypoactivity, respectively, in flies. We show that changes in Punch/GCH1 and dopamine levels do not depend on the ubiquitin ligase catalytic domain of Dube3a. In addition, both wild type Dube3a and a ubiquitination-defective Dube3a-C/A form were found at high levels in nuclear fractions and appear to be poly-ubiquitinated in vivo by endogenous Dube3a. We propose that the transcriptional co-activation function of Dube3a may regulate GCH1 activity in the brain. These results provide a connection between monoamine synthesis (dopamine/serotonin) and Dube3a expression that may explain why some individuals with ASD or AS respond better to selective serotonin reuptake inhibitors than others. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Quantitative dynamics and increased variability of segmentation gene expression in the Drosophila Krüppel and knirps mutants.

    PubMed

    Surkova, Svetlana; Golubkova, Elena; Manu; Panok, Lena; Mamon, Lyudmila; Reinitz, John; Samsonova, Maria

    2013-04-01

    Here we characterize the response of the Drosophila segmentation system to mutations in two gap genes, Kr and kni, in the form of single or double homozygotes and single heterozygotes. Segmentation gene expression in these genotypes was quantitatively monitored with cellular resolution in space and 6.5 to 13min resolution in time. As is the case with wild type, we found that gene expression domains in the posterior portion of the embryo shift to the anterior over time. In certain cases, such as the gt posterior domain in Kr mutants, the shifts are significantly larger than is seen in wild type embryos. We also investigated the effects of Kr and kni on the variability of gene expression. Mutations often produce variable phenotypes, and it is well known that the cuticular phenotype of Kr mutants is variable. We sought to understand the molecular basis of this effect. We find that throughout cycle 14A the relative levels of eve and ftz expression in stripes 2 and 3 are variable among individual embryos. Moreover, in Kr and kni mutants, unlike wild type, the variability in positioning of the posterior Hb domain and eve stripe 7 is not decreased or filtered with time. The posterior Gt domain in Kr mutants is highly variable at early times, but this variability decreases when this domain shifts in the anterior direction to the position of the neighboring Kni domain. In contrast to these findings, positional variability throughout the embryo does not decrease over time in double Kr;kni mutants. In heterozygotes the early expression patterns of segmentation genes resemble patterns seen in homozygous mutants but by the onset of gastrulation they become similar to the wild type patterns. Finally, we note that gene expression levels are reduced in Kr and kni mutant embryos and have a tendency to decrease over time. This is a surprising result in view of the role that mutual repression is thought to play in the gap gene system.

  2. Strategic priorities for increasing physical activity among adults age 50 and older: the national blueprint consensus conference summary report.

    PubMed

    Sheppard, Lisa; Senior, Jane; Park, Chae Hee; Mockenhaupt, Robin; Bazzarre, Terry; Chodzko-Zajko, Wojtek

    2003-12-01

    On May 1, 2001, a coalition of national organizations released a major planning document designed to develop a national strategy for the promotion of physically active lifestyles among the mid-life and older adult population. The National Blueprint: Increasing Physical Activity Among Adults Age 50 and Older was developed with input from 46 organizations with expertise in health, medicine, social and behavioral sciences, epidemiology, gerontology/geriatrics, clinical science, public policy, marketing, medical systems, community organization, and environmental issues. The Blueprint notes that, despite a wealth of evidence about the benefits of physical activity for mid-life and older persons, there has been little success in convincing age 50+ Americans to adopt physically active lifestyles. The Blueprint identifies barriers in the areas of research, home and community programs, medical systems, public policy and advocacy, and marketing and communications. In addition to identifying barriers, the Blueprint proposes a number of concrete strategies that could be employed in order to overcome the barriers to physical activity in society at large. This report summarizes the outcome of the National Blueprint Consensus Conference that was held in October 2002. In this conference, representatives of more than 50 national organizations convened in Washington, D.C. with the goal of identifying high priority and high feasibility strategies which would advance the National Blueprint and which could be initiated within the next 12 to 24 months. Participants in the consensus conference were assigned to one of five breakout groups: home and community, marketing, medical systems, public policy, and research. Each breakout group was charged with identifying the three highest priority strategies within their area for effectively increasing physical activity levels in the mid-life and older adult population. In addition to the 15 strategies identified by the breakout groups, three

  3. A rapid decrease in number of the complete ninja element and concomitant increase of the defective element in a strain of Drosophila simulans.

    PubMed

    Ogura, Keiji; Ohsako, Takashi; Yamamoto, Masa-Toshi

    2005-05-01

    The ninja element, originally isolated from an unstable white mutant strain white-milky (w(mky)) of Drosophila simulans, is a member of the retrotransposon family with long terminal repeats (LTRs). We show that ninja is present in high copy numbers in the w(mky)-derivative sublines white-chocolate (w(cho)) and white-persimmonl (w(psm1)), in a low copy number in another derivative subline white-milky 3 (w(mky3)), and in only a few copies in a wild type strain. We have cloned the ninja elements from these sublines and examined their structures. Most of the elements cloned (38 out of 41 independent clones) from w(cho) were full length. In contrast, only 9 of 23 independent clones from w(mky3) were full length. We hypothesize that ninja elements were integrated and lost frequently in the w(mky) strain and its derivative genomes, and that a rapid decrease in numbers of the ninja element was caused not by an increased rate of loss but by a reduction of integration of full length ninja elements in w(mky3). Each defective element had a unique deletion and/or an insertion except for the three from w(mky3), which had exactly the same 81-bp deletion in each of the 5' and 3' LTRs. The 5' and 3' ends of the deletion appeared to represent sequences similar to those of Drosophila consensussplicing sites. Ectopic splicing may have produced these defective ninja elements.

  4. Increasing Collaborative Efforts in Career Education, K-12. A Series of Mini-Conferences. Phase I. Final Report.

    ERIC Educational Resources Information Center

    Coley, Walton, Ed.

    During 1977-78, a series of Office of Career Education "mini-conferences" was held, each conference devoted to attacking the concept of collaboration in career education from a different perspective. The notes from this set of mini-conferences form the body of this document. (A companion document, CE 020 111, describes the follow-up…

  5. You Are What You Eat: Within-Subject Increases in Fruit and Vegetable Consumption Confer Beneficial Skin-Color Changes

    PubMed Central

    Whitehead, Ross D.; Re, Daniel; Xiao, Dengke; Ozakinci, Gozde; Perrett, David I.

    2012-01-01

    Background Fruit and vegetable consumption and ingestion of carotenoids have been found to be associated with human skin-color (yellowness) in a recent cross-sectional study. This carotenoid-based coloration contributes beneficially to the appearance of health in humans and is held to be a sexually selected cue of condition in other species. Methodology and Principal Findings Here we investigate the effects of fruit and vegetable consumption on skin-color longitudinally to determine the magnitude and duration of diet change required to change skin-color perceptibly. Diet and skin-color were recorded at baseline and after three and six weeks, in a group of 35 individuals who were without makeup, self-tanning agents and/or recent intensive UV exposure. Six-week changes in fruit and vegetable consumption were significantly correlated with changes in skin redness and yellowness over this period, and diet-linked skin reflectance changes were significantly associated with the spectral absorption of carotenoids and not melanin. We also used psychophysical methods to investigate the minimum color change required to confer perceptibly healthier and more attractive skin-coloration. Modest dietary changes are required to enhance apparent health (2.91 portions per day) and attractiveness (3.30 portions). Conclusions Increased fruit and vegetable consumption confers measurable and perceptibly beneficial effects on Caucasian skin appearance within six weeks. This effect could potentially be used as a motivational tool in dietary intervention. PMID:22412966

  6. You are what you eat: within-subject increases in fruit and vegetable consumption confer beneficial skin-color changes.

    PubMed

    Whitehead, Ross D; Re, Daniel; Xiao, Dengke; Ozakinci, Gozde; Perrett, David I

    2012-01-01

    Fruit and vegetable consumption and ingestion of carotenoids have been found to be associated with human skin-color (yellowness) in a recent cross-sectional study. This carotenoid-based coloration contributes beneficially to the appearance of health in humans and is held to be a sexually selected cue of condition in other species. Here we investigate the effects of fruit and vegetable consumption on skin-color longitudinally to determine the magnitude and duration of diet change required to change skin-color perceptibly. Diet and skin-color were recorded at baseline and after three and six weeks, in a group of 35 individuals who were without makeup, self-tanning agents and/or recent intensive UV exposure. Six-week changes in fruit and vegetable consumption were significantly correlated with changes in skin redness and yellowness over this period, and diet-linked skin reflectance changes were significantly associated with the spectral absorption of carotenoids and not melanin. We also used psychophysical methods to investigate the minimum color change required to confer perceptibly healthier and more attractive skin-coloration. Modest dietary changes are required to enhance apparent health (2.91 portions per day) and attractiveness (3.30 portions). Increased fruit and vegetable consumption confers measurable and perceptibly beneficial effects on Caucasian skin appearance within six weeks. This effect could potentially be used as a motivational tool in dietary intervention.

  7. Ziram, a pesticide associated with increased risk for Parkinson’s disease, differentially affects the presynaptic function of aminergic and glutamatergic nerve terminals at the Drosophila neuromuscular junction

    PubMed Central

    Martin, Ciara A.; Myers, Katherine M.; Chen, Audrey; Martin, Nathan T.; Barajas, Angel; Schweizer, Felix E.; Krantz, David E.

    2015-01-01

    Multiple populations of aminergic neurons are affected in Parkinson’s disease (PD), with serotonergic and noradrenergic loci responsible for some non-motor symptoms. Environmental toxins, such as the dithiocarbamate fungicide ziram, significantly increase the risk of developing PD and the attendant spectrum of both motor and non-motor symptoms. The mechanisms by which ziram and other environmental toxins increase the risk of PD, and the potential effects of these toxins on aminergic neurons, remain unclear. To determine the relative effects of ziram on the synaptic function of aminergic versus non-aminergic neurons, we used live-imaging at the Drosophila melanogaster larval neuromuscular junction (NMJ). In contrast to nearly all other studies of this model synapse, we imaged presynaptic function at both glutamatergic Type Ib and aminergic Type II boutons, the latter responsible for storage and release of octopamine, the invertebrate equivalent of noradrenalin. To quantify the kinetics of exo- and endo- cytosis, we employed an acid-sensitive form of GFP fused to the Drosophila vesicular monoamine transporter (DVMAT-pHluorin). Additional genetic probes were used to visualize intracellular calcium flux (GCaMP) and voltage changes (ArcLight). We find that at glutamatergic Type Ib terminals, exposure to ziram increases exocytosis and inhibits endocytosis. By contrast, at octopaminergic Type II terminals, ziram has no detectable effect on exocytosis and dramatically inhibits endocytosis. In contrast to other reports on the neuronal effects of ziram, these effects do not appear to result from perturbation of the UPS or calcium homeostasis. Unexpectedly, ziram also caused spontaneous and synchronized bursts of calcium influx (measured by GCaMP) and electrical activity (measured by ArcLight) at aminergic Type II, but not glutamatergic Type Ib, nerve terminals. These events are sensitive to both tetrodotoxin and cadmium chloride, and thus appear to represent spontaneous

  8. A local difference in Hedgehog signal transduction increases mechanical cell bond tension and biases cell intercalations along the Drosophila anteroposterior compartment boundary.

    PubMed

    Rudolf, Katrin; Umetsu, Daiki; Aliee, Maryam; Sui, Liyuan; Jülicher, Frank; Dahmann, Christian

    2015-11-15

    Tissue organization requires the interplay between biochemical signaling and cellular force generation. The formation of straight boundaries separating cells with different fates into compartments is important for growth and patterning during tissue development. In the developing Drosophila wing disc, maintenance of the straight anteroposterior (AP) compartment boundary involves a local increase in mechanical tension at cell bonds along the boundary. The biochemical signals that regulate mechanical tension along the AP boundary, however, remain unknown. Here, we show that a local difference in Hedgehog signal transduction activity between anterior and posterior cells is necessary and sufficient to increase mechanical tension along the AP boundary. This difference in Hedgehog signal transduction is also required to bias cell rearrangements during cell intercalations to keep the characteristic straight shape of the AP boundary. Moreover, severing cell bonds along the AP boundary does not reduce tension at neighboring bonds, implying that active mechanical tension is upregulated, cell bond by cell bond. Finally, differences in the expression of the homeodomain-containing protein Engrailed also contribute to the straight shape of the AP boundary, independently of Hedgehog signal transduction and without modulating cell bond tension. Our data reveal a novel link between local differences in Hedgehog signal transduction and a local increase in active mechanical tension of cell bonds that biases junctional rearrangements. The large-scale shape of the AP boundary thus emerges from biochemical signals inducing patterns of active tension on cell bonds. © 2015. Published by The Company of Biologists Ltd.

  9. Increased abundance of frost mRNA during recovery from cold stress is not essential for cold tolerance in adult Drosophila melanogaster.

    PubMed

    Udaka, H; Percival-Smith, A; Sinclair, B J

    2013-10-01

    Frost (Fst) is a candidate gene associated with the response to cold in Drosophila melanogaster because Fst mRNA accumulation increases during recovery from low temperature exposure. We investigated the contribution of Fst expression to chill-coma recovery time, acute cold tolerance and rapid cold hardening (RCH) in adult D. melanogaster by knocking down Fst mRNA expression using GAL4/UAS-mediated RNA interference. In this experiment, four UAS-Fst and one tubulin-GAL4 lines were used. We predicted that if Fst is essential for cold tolerance phenotypes, flies with low Fst mRNA levels should be less cold tolerant than flies with normal levels of cold-induced Fst mRNA. Cold-induced Fst abundance and recovery time from chill-coma were not negatively correlated in male or female flies. Survival of 2 h exposures to sub-zero temperatures in Fst knockdown lines was not lower than that in a control line. Moreover, a low temperature pretreatment increased survival of severe cold exposure in flies regardless of Fst abundance level during recovery from cold stress, suggesting that Fst expression is not essential for RCH. Thus, cold-induced Fst accumulation is not essential for cold tolerance measured as chill-coma recovery time, survival to acute cold stress and RCH response in adult D. melanogaster.

  10. Decreased MCM2-6 in Drosophila S2 Cells Does Not Generate Significant DNA Damage or Cause a Marked Increase in Sensitivity to Replication Interference

    PubMed Central

    Crevel, Isabelle; Crevel, Gilles; Gostan, Thierry; de Renty, Christelle; Coulon, Vincent; Cotterill, Sue

    2011-01-01

    A reduction in the level of some MCM proteins in human cancer cells (MCM5 in U20S cells or MCM3 in Hela cells) causes a rapid increase in the level of DNA damage under normal conditions of cell proliferation and a loss of viability when the cells are subjected to replication interference. Here we show that Drosophila S2 cells do not appear to show the same degree of sensitivity to MCM2-6 reduction. Under normal cell growth conditions a reduction of >95% in the levels of MCM3, 5, and 6 causes no significant short term alteration in the parameters of DNA replication or increase in DNA damage. MCM depleted cells challenged with HU do show a decrease in the density of replication forks compared to cells with normal levels of MCM proteins, but this produces no consistent change in the levels of DNA damage observed. In contrast a comparable reduction of MCM7 levels has marked effects on viability, replication parameters and DNA damage in the absence of HU treatment. PMID:22102875

  11. ARID5B polymorphism confers an increased risk to acquire specific MLL rearrangements in early childhood leukemia

    PubMed Central

    2014-01-01

    Background Acute leukemia in early age (EAL) is characterized by acquired genetic alterations such as MLL rearrangements (MLL-r). The aim of this case-controlled study was to investigate whether single nucleotide polymorphisms (SNPs) of IKZF1, ARID5B, and CEBPE could be related to the onset of EAL cases (<24 months-old at diagnosis). Methods The SNPs (IKZF1 rs11978267, ARID5B rs10821936 and rs10994982, CEBPE rs2239633) were genotyped in 265 cases [169 acute lymphoblastic leukemia (ALL) and 96 acute myeloid leukaemia (AML)] and 505 controls by Taqman allelic discrimination assay. Logistic regression was used to evaluate the association between SNPs of cases and controls, adjusted on skin color and/or age. The risk was determined by calculating odds ratios (ORs) with 95% confidence interval (CI). Results Children with the IKZF1 SNP had an increased risk of developing MLL-germline ALL in white children. The heterozygous/mutant genotype in ARID5B rs10994982 significantly increased the risk for MLL-germline leukemia in white and non-white children (OR 2.60, 95% CI: 1.09-6.18 and OR 3.55, 95% CI: 1.57-8.68, respectively). The heterozygous genotype in ARID5B rs10821936 increased the risk for MLL-r leukemia in both white and non-white (OR 2.06, 95% CI: 1.12-3.79 and OR 2.36, 95% CI: 1.09-5.10, respectively). Furthermore, ARID5B rs10821936 conferred increased risk for MLL-MLLT3 positive cases (OR 7.10, 95% CI:1.54-32.68). Our data do not show evidence that CEBPE rs2239633 confers increased genetic susceptibility to EAL. Conclusions IKZF1 and CEBPE variants seem to play a minor role in genetic susceptibility to EAL, while ARID5B rs10821936 increased the risk of MLL-MLLT3. This result shows that genetic susceptibility could be associated with the differences regarding MLL breakpoints and partner genes. PMID:24564228

  12. Safeguarding genetic information in Drosophila.

    PubMed

    Su, Tin Tin

    2011-12-01

    Eukaryotic cells employ a plethora of conserved proteins and mechanisms to ensure genome integrity. In metazoa, these mechanisms must operate in the context of organism development. This mini-review highlights two emerging features of DNA damage responses in Drosophila: a crosstalk between DNA damage responses and components of the spindle assembly checkpoint, and increasing evidence for the effect of DNA damage on the developmental program at multiple points during the Drosophila life cycle.

  13. Heritable Endosymbionts of Drosophila

    PubMed Central

    Mateos, Mariana; Castrezana, Sergio J.; Nankivell, Becky J.; Estes, Anne M.; Markow, Therese A.; Moran, Nancy A.

    2006-01-01

    Although heritable microorganisms are increasingly recognized as widespread in insects, no systematic screens for such symbionts have been conducted in Drosophila species (the primary insect genetic models for studies of evolution, development, and innate immunity). Previous efforts screened relatively few Drosophila lineages, mainly for Wolbachia. We conducted an extensive survey of potentially heritable endosymbionts from any bacterial lineage via PCR screens of mature ovaries in 181 recently collected fly strains representing 35 species from 11 species groups. Due to our fly sampling methods, however, we are likely to have missed fly strains infected with sex ratio-distorting endosymbionts. Only Wolbachia and Spiroplasma, both widespread in insects, were confirmed as symbionts. These findings indicate that in contrast to some other insect groups, other heritable symbionts are uncommon in Drosophila species, possibly reflecting a robust innate immune response that eliminates many bacteria. A more extensive survey targeted these two symbiont types through diagnostic PCR in 1225 strains representing 225 species from 32 species groups. Of these, 19 species were infected by Wolbachia while only 3 species had Spiroplasma. Several new strains of Wolbachia and Spiroplasma were discovered, including ones divergent from any reported to date. The phylogenetic distribution of Wolbachia and Spiroplasma in Drosophila is discussed. PMID:16783009

  14. Hydrogen Peroxide Removes TRPM4 Current Desensitization Conferring Increased Vulnerability to Necrotic Cell Death*

    PubMed Central

    Simon, Felipe; Leiva-Salcedo, Elías; Armisén, Ricardo; Riveros, Ana; Cerda, Oscar; Varela, Diego; Eguiguren, Ana Luisa; Olivero, Pablo; Stutzin, Andrés

    2010-01-01

    Necrosis is associated with an increase in plasma membrane permeability, cell swelling, and loss of membrane integrity with subsequent release of cytoplasmic constituents. Severe redox imbalance by overproduction of reactive oxygen species is one of the main causes of necrosis. Here we demonstrate that H2O2 induces a sustained activity of TRPM4, a Ca2+-activated, Ca2+-impermeant nonselective cation channel resulting in an increased vulnerability to cell death. In HEK 293 cells overexpressing TRPM4, H2O2 was found to eliminate in a dose-dependent manner TRPM4 desensitization. Site-directed mutagenesis experiments revealed that the Cys1093 residue is crucial for the H2O2-mediated loss of desensitization. In HeLa cells, which endogenously express TRPM4, H2O2 elicited necrosis as well as apoptosis. H2O2-mediated necrosis but not apoptosis was abolished by replacement of external Na+ ions with sucrose or the non-permeant cation N-methyl-d-glucamine and by knocking down TRPM4 with a shRNA directed against TRPM4. Conversely, transient overexpression of TRPM4 in HeLa cells in which TRPM4 was previously silenced re-established vulnerability to H2O2-induced necrotic cell death. In addition, HeLa cells exposed to H2O2 displayed an irreversible loss of membrane potential, which was prevented by TRPM4 knockdown. PMID:20884614

  15. Suppression of Phospholipase Dγs Confers Increased Aluminum Resistance in Arabidopsis thaliana

    PubMed Central

    Zhao, Jian; Wang, Cunxi; Bedair, Mohamed; Welti, Ruth; W. Sumner, Lloyd; Baxter, Ivan; Wang, Xuemin

    2011-01-01

    Aluminum (Al) toxicity is the major stress in acidic soil that comprises about 50% of the world's arable land. The complex molecular mechanisms of Al toxicity have yet to be fully determined. As a barrier to Al entrance, plant cell membranes play essential roles in plant interaction with Al, and lipid composition and membrane integrity change significantly under Al stress. Here, we show that phospholipase Dγs (PLDγs) are induced by Al stress and contribute to Al-induced membrane lipid alterations. RNAi suppression of PLDγ resulted in a decrease in both PLDγ1 and PLDγ2 expression and an increase in Al resistance. Genetic disruption of PLDγ1 also led to an increased tolerance to Al while knockout of PLDγ2 did not. Both RNAi-suppressed and pldγ1-1 mutants displayed better root growth than wild-type under Al stress conditions, and PLDγ1-deficient plants had less accumulation of callose, less oxidative damage, and less lipid peroxidation compared to wild-type plants. Most phospholipids and glycolipids were altered in response to Al treatment of wild-type plants, whereas fewer changes in lipids occurred in response to Al stress in PLDγ mutant lines. Our results suggest that PLDγs play a role in membrane lipid modulation under Al stress and that high activities of PLDγs negatively modulate plant tolerance to Al. PMID:22163277

  16. The Selector Gene apterous and Notch Are Required to Locally Increase Mechanical Cell Bond Tension at the Drosophila Dorsoventral Compartment Boundary

    PubMed Central

    Michel, Marcus; Aliee, Maryam; Rudolf, Katrin; Bialas, Lisa; Jülicher, Frank; Dahmann, Christian

    2016-01-01

    The separation of cells with distinct fates and functions is important for tissue and organ formation during animal development. Regions of different fates within tissues are often separated from another along straight boundaries. These compartment boundaries play a crucial role in tissue patterning and growth by stably positioning organizers. In Drosophila, the wing imaginal disc is subdivided into a dorsal and a ventral compartment. Cells of the dorsal, but not ventral, compartment express the selector gene apterous. Apterous expression sets in motion a gene regulatory cascade that leads to the activation of Notch signaling in a few cell rows on either side of the dorsoventral compartment boundary. Both Notch and apterous mutant clones disturb the separation of dorsal and ventral cells. Maintenance of the straight shape of the dorsoventral boundary involves a local increase in mechanical tension at cell bonds along the boundary. The mechanisms by which cell bond tension is locally increased however remain unknown. Here we use a combination of laser ablation of cell bonds, quantitative image analysis, and genetic mutants to show that Notch and Apterous are required to increase cell bond tension along the dorsoventral compartment boundary. Moreover, clonal expression of the Apterous target gene capricious results in cell separation and increased cell bond tension at the clone borders. Finally, using a vertex model to simulate tissue growth, we find that an increase in cell bond tension at the borders of cell clones, but not throughout the cell clone, can lead to cell separation. We conclude that Apterous and Notch maintain the characteristic straight shape of the dorsoventral compartment boundary by locally increasing cell bond tension. PMID:27552097

  17. Ankylosing spondylitis confers substantially increased risk of clinical spine fractures: a nationwide case-control study.

    PubMed

    Prieto-Alhambra, D; Muñoz-Ortego, J; De Vries, F; Vosse, D; Arden, N K; Bowness, P; Cooper, C; Diez-Perez, A; Vestergaard, P

    2015-01-01

    Ankylosing spondylitis (AS) leads to osteopenia/osteoporosis and spine rigidity. We conducted a case-control study and found that AS-affected patients have a 5-fold and 50% increased risk of clinical spine and all clinical fractures, respectively. Excess risk of both is highest in the first years and warrants an early bone health assessment after diagnosis. Ankylosing spondylitis (AS) is related to spine rigidity and reduced bone mass, but data on its impact on fracture risk are scarce. We aimed to study the association between AS and clinical fractures using a case-control design. From the Danish Health Registries, we identified all subjects who sustained a fracture in the year 2000 (cases) and matched up to three controls by year of birth, gender and region. Clinically diagnosed AS was identified using International Classification of Diseases, 8th revision (ICD-8; 71249), and International Classification of Diseases, 10th revision (ICD-10; M45) codes. We also studied the impact of AS duration. Conditional logistic regression was used to estimate crude and adjusted odds ratios (ORs) for non-traumatic fractures (any site, clinical spine and non-vertebral) according to AS status and time since AS diagnosis. Multivariate models were adjusted for fracture history, socio-economic status, previous medical consultations, alcoholism and use of oral glucocorticoids. We identified 139/124,655 (0.11%) AS fracture cases, compared to 271/373,962 (0.07%) AS controls. Unadjusted (age- and gender-matched) odds ratio (OR) were 1.54 [95% confidence interval (95%CI) 1.26-1.89] for any fracture, 5.42 [2.50-11.70] for spine and 1.39 [1.12-1.73] for non-vertebral fracture. The risk peaked in the first 2.5 years following AS diagnosis: OR 2.69 [1.84-3.92] for any fracture. Patients with AS have a 5-fold higher risk of clinical spine fracture and a 35% increased risk of non-vertebral fracture. This excess risk peaks early, in the first 2.5 years of AS disease. Patients should be assessed

  18. Dietary flavonoid fisetin increases abundance of high-molecular-mass hyaluronan conferring resistance to prostate oncogenesis.

    PubMed

    Lall, Rahul K; Syed, Deeba N; Khan, Mohammad Imran; Adhami, Vaqar M; Gong, Yuansheng; Lucey, John A; Mukhtar, Hasan

    2016-09-01

    We and others have shown previously that fisetin, a plant flavonoid, has therapeutic potential against many cancer types. Here, we examined the probable mechanism of its action in prostate cancer (PCa) using a global metabolomics approach. HPLC-ESI-MS analysis of tumor xenografts from fisetin-treated animals identified several metabolic targets with hyaluronan (HA) as the most affected. Efficacy of fisetin on HA was then evaluated in vitro and also in vivo in the transgenic TRAMP mouse model of PCa. Size exclusion chromatography-multiangle laser light scattering (SEC-MALS) was performed to analyze the molar mass (Mw) distribution of HA. Fisetin treatment downregulated intracellular and secreted HA levels both in vitro and in vivo Fisetin inhibited HA synthesis and degradation enzymes, which led to cessation of HA synthesis and also repressed the degradation of the available high-molecular-mass (HMM)-HA. SEC-MALS analysis of intact HA fragment size revealed that cells and animals have more abundance of HMM-HA and less of low-molecular-mass (LMM)-HA upon fisetin treatment. Elevated HA levels have been shown to be associated with disease progression in certain cancer types. Biological responses triggered by HA mainly depend on the HA polymer length where HMM-HA represses mitogenic signaling and has anti-inflammatory properties whereas LMM-HA promotes proliferation and inflammation. Similarly, Mw analysis of secreted HA fragment size revealed less HMM-HA is secreted that allowed more HMM-HA to be retained within the cells and tissues. Our findings establish that fisetin is an effective, non-toxic, potent HA synthesis inhibitor, which increases abundance of antiangiogenic HMM-HA and could be used for the management of PCa. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Expansion of GA Dinucleotide Repeats Increases the Density of CLAMP Binding Sites on the X-Chromosome to Promote Drosophila Dosage Compensation

    PubMed Central

    Chery, Jessica; Siggers, Trevor; Boor, Sonia; Bliss, Jacob; Liu, Wei; Jogl, Gerwald; Rohs, Remo; Singh, Nadia D.; Bulyk, Martha L.; Tolstorukov, Michael Y.; Larschan, Erica

    2016-01-01

    Dosage compensation is an essential process that equalizes transcript levels of X-linked genes between sexes by forming a domain of coordinated gene expression. Throughout the evolution of Diptera, many different X-chromosomes acquired the ability to be dosage compensated. Once each newly evolved X-chromosome is targeted for dosage compensation in XY males, its active genes are upregulated two-fold to equalize gene expression with XX females. In Drosophila melanogaster, the CLAMP zinc finger protein links the dosage compensation complex to the X-chromosome. However, the mechanism for X-chromosome identification has remained unknown. Here, we combine biochemical, genomic and evolutionary approaches to reveal that expansion of GA-dinucleotide repeats likely accumulated on the X-chromosome over evolutionary time to increase the density of CLAMP binding sites, thereby driving the evolution of dosage compensation. Overall, we present new insight into how subtle changes in genomic architecture, such as expansions of a simple sequence repeat, promote the evolution of coordinated gene expression. PMID:27414415

  20. Enhanced Locomotor Activity Is Required to Exert Dietary Restriction-Dependent Increase of Stress Resistance in Drosophila.

    PubMed

    Ghimire, Saurav; Kim, Man Su

    2015-01-01

    Dietary restriction (DR) is known to be one of the most effective interventions to increase stress resistance, yet the mechanisms remain elusive. One of the most obvious DR-induced changes in phenotype is an increase in locomotor activity. Although it is conceptually perceivable that nutritional scarcity should prompt enhanced foraging behavior to garner additional dietary resources, the significance of enhanced movement activity has not been associated with the DR-dependent increase of stress resistance. In this study, we confirmed that flies raised on DR exhibited enhanced locomotive activity and increased stress resistance. Excision of fly wings minimized the DR-induced increase in locomotive activity, which resulted in attenuation of the DR-dependent increase of stress resistance. The possibility that wing clipping counteracts the DR by coercing flies to have more intake was ruled out since it did not induce any weight gain. Rather it was found that elimination of reactive oxygen species (ROS) that is enhanced by DR-induced upregulation of expression of antioxidant genes was significantly reduced by wing clipping. Collectively, our data suggests that DR increased stress resistance by increasing the locomotor activity, which upregulated expression of protective genes including, but not limited to, ROS scavenger system.

  1. A Drosophila model for developmental nicotine exposure.

    PubMed

    Velazquez-Ulloa, Norma Andrea

    2017-01-01

    Despite the known health risks of tobacco smoking, many people including pregnant women continue smoking. The effects of developmental nicotine exposure are known, but the underlying mechanisms are not well understood. Drosophila melanogaster is a model organism that can be used for uncovering genetic and molecular mechanisms for drugs of abuse. Here I show that Drosophila can be a model to elucidate the mechanisms for nicotine's effects on a developing organism. Drosophila reared on nicotine food display developmental and behavioral effects similar to those in mammals including decreased survival and weight, increased developmental time, and decreased sensitivity to acute nicotine and ethanol. The Drosophila nicotinic acetylcholine receptor subunit alpha 7 (Dα7) mediates some of these effects. A novel role for Dα7 on ethanol sedation in Drosophila is also shown. Future research taking advantage of the genetic and molecular tools for Drosophila will allow additional discovery of the mechanisms behind the effects of nicotine during development.

  2. Patient Participation at Health Care Conferences: Engaged Patients Increase Information Flow, Expand Propagation, and Deepen Engagement in the Conversation of Tweets Compared to Physicians or Researchers.

    PubMed

    Utengen, Audun; Rouholiman, Dara; Gamble, Jamison G; Grajales Iii, Francisco Jose; Pradhan, Nisha; Staley, Alicia C; Bernstein, Liza; Young, Sean D; Clauson, Kevin A; Chu, Larry F

    2017-08-17

    Health care conferences present a unique opportunity to network, spark innovation, and disseminate novel information to a large audience, but the dissemination of information typically stays within very specific networks. Social network analysis can be adopted to understand the flow of information between virtual social communities and the role of patients within the network. The purpose of this study is to examine the impact engaged patients bring to health care conference social media information flow and how they expand dissemination and distribution of tweets compared to other health care conference stakeholders such as physicians and researchers. From January 2014 through December 2016, 7,644,549 tweets were analyzed from 1672 health care conferences with at least 1000 tweets who had registered in Symplur's Health Care Hashtag Project from 2014 to 2016. The tweet content was analyzed to create a list of the top 100 influencers by mention from each conference, who were then subsequently categorized by stakeholder group. Multivariate linear regression models were created using stepwise function building to identify factors explaining variability as predictor variables for the model in which conference tweets were taken as the dependent variable. Inclusion of engaged patients in health care conference social media was low compared to that of physicians and has not significantly changed over the last 3 years. When engaged patient voices are included in health care conferences, they greatly increase information flow as measured by total tweet volume (beta=301.6) compared to physicians (beta=137.3, P<.001), expand propagation of information tweeted during a conference as measured by social media impressions created (beta=1,700,000) compared to physicians (beta=270,000, P<.001), and deepen engagement in the tweet conversation as measured by replies to their tweets (beta=24.4) compared to physicians (beta=5.5, P<.001). Social network analysis of hubs and authorities

  3. Drosophila spermiogenesis

    PubMed Central

    Fabian, Lacramioara; Brill, Julie A.

    2012-01-01

    Drosophila melanogaster spermatids undergo dramatic morphological changes as they differentiate from small round cells approximately 12 μm in diameter into highly polarized, 1.8 mm long, motile sperm capable of participating in fertilization. During spermiogenesis, syncytial cysts of 64 haploid spermatids undergo synchronous differentiation. Numerous changes occur at a subcellular level, including remodeling of existing organelles (mitochondria, nuclei), formation of new organelles (flagellar axonemes, acrosomes), polarization of elongating cysts and plasma membrane addition. At the end of spermatid morphogenesis, organelles, mitochondrial DNA and cytoplasmic components not needed in mature sperm are stripped away in a caspase-dependent process called individualization that results in formation of individual sperm. Here, we review the stages of Drosophila spermiogenesis and examine our current understanding of the cellular and molecular mechanisms involved in shaping male germ cell-specific organelles and forming mature, fertile sperm. PMID:23087837

  4. Epithelial-to-Mesenchymal Transition of RPE Cells In Vitro Confers Increased β1,6-N-Glycosylation and Increased Susceptibility to Galectin-3 Binding

    PubMed Central

    Priglinger, Claudia S.; Obermann, Jara; Szober, Christoph M.; Merl-Pham, Juliane; Ohmayer, Uli; Behler, Jennifer; Gruhn, Fabian; Kreutzer, Thomas C.; Wertheimer, Christian; Geerlof, Arie; Priglinger, Siegfried G.; Hauck, Stefanie M.

    2016-01-01

    Epithelial-to-mesenchymal transition (EMT) of retinal pigment epithelial cells is a crucial event in the onset of proliferative vitreoretinopathy (PVR), the most common reason for treatment failure in retinal detachment surgery. We studied alterations in the cell surface glycan expression profile upon EMT of RPE cells and focused on its relevance for the interaction with galectin-3 (Gal-3), a carbohydrate binding protein, which can inhibit attachment and spreading of human RPE cells in a dose- and carbohydrate-dependent manner, and thus bares the potential to counteract PVR-associated cellular events. Lectin blot analysis revealed that EMT of RPE cells in vitro confers a glycomic shift towards an abundance of Thomsen-Friedenreich antigen, poly-N-acetyllactosamine chains, and complex-type branched N-glycans. Using inhibitors of glycosylation we found that both, binding of Gal-3 to the RPE cell surface and Gal-3-mediated inhibition of RPE attachment and spreading, strongly depend on the interaction of Gal-3 with tri- or tetra-antennary complex type N-glycans and sialylation of glycans but not on complex-type O-glycans. Importantly, we found that β1,6 N-acetylglucosaminyltransferase V (Mgat5), the key enzyme catalyzing the synthesis of tetra- or tri-antennary complex type N-glycans, is increased upon EMT of RPE cells. Silencing of Mgat5 by siRNA and CRISPR-Cas9 genome editing resulted in reduced Gal-3 binding. We conclude from these data that binding of recombinant Gal-3 to the RPE cell surface and inhibitory effects on RPE attachment and spreading largely dependent on interaction with Mgat5 modified N-glycans, which are more abundant on dedifferentiated than on the healthy, native RPE cells. Based on these findings we hypothesize that EMT of RPE cells in vitro confers glycomic changes, which account for high affinity binding of recombinant Gal-3, particularly to the cell surface of myofibroblastic RPE. From a future perspective recombinant Gal-3 may disclose a

  5. Secretory competence in a gateway endocrine cell conferred by the nuclear receptor βFTZ-F1 enables stage-specific ecdysone responses throughout development in Drosophila.

    PubMed

    Cho, Kook-Ho; Daubnerová, Ivana; Park, Yoonseong; Zitnan, Dusan; Adams, Michael E

    2014-01-15

    Hormone-induced changes in gene expression initiate periodic molts and metamorphosis during insect development. Successful execution of these developmental steps depends upon successive phases of rising and falling 20-hydroxyecdysone (20E) levels, leading to a cascade of nuclear receptor-driven transcriptional activity that enables stage- and tissue-specific responses to the steroid. Among the cellular processes associated with declining steroids is acquisition of secretory competence in endocrine Inka cells, the source of ecdysis triggering hormones (ETHs). We show here that Inka cell secretory competence is conferred by the orphan nuclear receptor βFTZ-F1. Selective RNA silencing of βftz-f1 in Inka cells prevents ETH release, causing developmental arrest at all stages. Affected larvae display buttoned-up, the ETH-null phenotype characterized by double mouthparts, absence of ecdysis behaviors, and failure to shed the old cuticle. During the mid-prepupal period, individuals fail to translocate the air bubble, execute head eversion and elongate incipient wings and legs. Those that escape to the adult stage are defective in wing expansion and cuticle sclerotization. Failure to release ETH in βftz-f1 silenced animals is indicated by persistent ETH immunoreactivity in Inka cells. Arrested larvae are rescued by precisely-timed ETH injection or Inka cell-targeted βFTZ-F1 expression. Moreover, premature βftz-f1 expression in these cells also results in developmental arrest. The Inka cell therefore functions as a "gateway cell", whose secretion of ETH serves as a key downstream physiological output enabling stage-specific responses to 20E that are required to advance through critical developmental steps. This secretory function depends on transient and precisely timed βFTZ-F1 expression late in the molt as steroids decline.

  6. Courtship Song Does Not Increase the Rate of Adaptation to a Thermally Stressful Environment in a Drosophila melanogaster Laboratory Population

    PubMed Central

    Cabral, Larry G.; Holland, Brett

    2014-01-01

    Courtship song in D. melanogaster contributes substantially to male mating success through female selection. We used experimental evolution to test whether this display trait is maintained through adaptive female selection because it indicates heritable male quality for thermal stress tolerance. We used non-displaying, outbred populations of D. melanogaster (nub1) mutants and measured their rate of adaptation to a new, thermally stressful environment, relative to wild-type control populations that retained courtship song. This design retains sexually selected conflict in both treatments. Thermal stress should select across genomes for newly beneficial alleles, increasing the available genetic and phenotypic variation and, therefore, the magnitude of female benefit derived from courtship song. Following introduction to the thermally stressful environment, net reproductive rate decreased 50% over four generations, and then increased 19% over the following 16 generations. There were no differences between the treatments. Possible explanations for these results are discussed. PMID:25365209

  7. Microenvironment mediated alterations to metabolic pathways confer increased chemo-resistance in CD133+ tumor initiating cells

    PubMed Central

    Nomura, Alice; Dauer, Patricia; Gupta, Vineet; McGinn, Olivia; Arora, Nivedita; Majumdar, Kaustav; III, Charles Uhlrich; Dalluge, Joseph; Dudeja, Vikas; Saluja, Ashok; Banerjee, Sulagna

    2016-01-01

    Chemoresistance in pancreatic cancer has been attributed to tumor-initiating cells (TICs), a minor sub-population of tumor cells. However, the mechanism of chemo-resistance in these cells is still unclear. In the current study, immunohistochemical analysis of LSL-KrasG12D; LSL-Trp53R172H; PdxCre (KPC) murine tumors indicated that hypoxic regions developed through tumor progression. This hypoxic “niche” correlated with increased CD133+ population that had an increased HIF1A activity. Consistent with this observation, CD133+ cells had increased glucose uptake and activity of glycolytic pathway enzymes compared to CD133− cells. Mass spectrometric analysis (UPLC-TQD) following metabolic labeling of CD133+ cells with [13C]-U6 glucose confirmed this observation. Furthermore, although both populations had functionally active mitochondria, CD133+ cells had low mitochondrial complex I and complex IV activity and lesser accumulation of ROS in response to standard chemotherapeutic compounds like paclitaxel, 5FU and gemcitabine. CD133+ cells also showed increased resistance to all three chemotherapeutic compounds and treatment with Glut1 inhibitor (STF31) reversed this resistance, promoting apoptotic death in these cells similar to CD133− cells. Our study indicates that the altered metabolic profile of CD133+ pancreatic TIC protects them against apoptosis, by reducing accumulation of ROS induced by standard chemotherapeutic agents, thereby confering chemoresistance. Since resistance to existing chemotherapy contributes to the poor prognosis in pancreatic cancer, our study paves the way for identifying novel therapeutic targets for managing chemoresistance and tumor recurrence in pancreatic cancer. PMID:27472388

  8. Lycopene, resveratrol, vitamin C and FeSO4 increase damage produced by pro-oxidant carcinogen 4-nitroquinoline-1-oxide in Drosophila melanogaster: Xenobiotic metabolism implications.

    PubMed

    Dueñas-García, I E; Heres-Pulido, M E; Arellano-Llamas, M R; De la Cruz-Núñez, J; Cisneros-Carrillo, V; Palacios-López, C S; Acosta-Anaya, L; Santos-Cruz, L F; Castañeda-Partida, L; Durán-Díaz, A

    2017-05-01

    4-nitroquinoline-1-oxide (4-NQO) is a pro-oxidant carcinogen bioactivated by xenobiotic metabolism (XM). We investigated if antioxidants lycopene [0.45, 0.9, 1.8 μM], resveratrol [11, 43, 172 μM], and vitamin C [5.6 mM] added or not with FeSO4 [0.06 mM], modulate the genotoxicity of 4-NQO [2 mM] with the Drosophila wing spot test standard (ST) and high bioactivation (HB) crosses, with inducible and high levels of cytochromes P450, respectively. The genotoxicity of 4-NQO was higher when dissolved in an ethanol - acetone mixture. The antioxidants did not protect against 4-NQO in any of both crosses. In the ST cross, resveratrol [11 μM], vitamin C and FeSO4 resulted in genotoxicity; the three antioxidants and FeSO4 increased the damage of 4-NQO. In the HB cross, none of the antioxidants, neither FeSO4, were genotoxic. Only resveratrol [172 μM] + 4-NQO increased the genotoxic activity in both crosses. We concluded that the effects of the antioxidants, FeSO4 and the modulation of 4-NQO were the result of the difference of Cyp450s levels, between the ST and HB crosses. We propose that the basal levels of the XM's enzymes in the ST cross interacted with a putative pro-oxidant activity of the compounds added to the pro-oxidant effects of 4-NQO. Copyright © 2017. Published by Elsevier Ltd.

  9. [VARIOUS ALLELES OF HSF HEAT-SHOCK TRANSCRIPTION FACTOR OF DROSOPHILA MELANOGASTER INCREASE VIABILITY OF ITS CARRIERS IN UNFAVORABLE ENVIRONMENTS].

    PubMed

    Weisman, N Ya; Evgen'ev, M B; Golubovsky, M D

    2015-01-01

    We found increased viability in heterozygous carriers of hsf heat shock transcription factor n comparison with wild type. The effect depends on temperature, sex and direction of crosses. Viability effect is more evident in conditions of soft temperature stress. The males are more sensitive. The maternal effect is observed: if hsf*allele came from mother, the viability effect is stronger. The survival curves of heterozygotes on hsf-1 and hsf-4 alleles are similar in spite of HSF-4 protein is slightly active on normal temperature.

  10. Mast cells control insulitis and increase Treg cells to confer protection against STZ-induced type 1 diabetes in mice.

    PubMed

    Carlos, Daniela; Yaochite, Juliana N U; Rocha, Fernanda A; Toso, Vanina D; Malmegrim, Kelen C R; Ramos, Simone G; Jamur, Maria C; Oliver, Constance; Camara, Niels O; Andrade, Marcus V M; Cunha, Fernando Q; Silva, João S

    2015-10-01

    Quantitative alterations in mast cell numbers in pancreatic lymph nodes (PLNs) have been reported to be associated with type 1 diabetes (T1D) progression, but their potential role during T1D remains unclear. In this study, we evaluated the role of mast cells in T1D induced by multiple low-dose streptozotocin (MLD-STZ) treatments, using two strains of mast cell-deficient mice (W/W(v) or Wsh/Wsh) and the adoptive transfer of mast cells. Mast cell deficient mice developed severe insulitis and accelerated hyperglycemia, with 100% of mice becoming diabetic compared to their littermates. In parallel, these diabetic mice had decreased numbers of T regulatory (Treg) cells in the PLNs. Additionally, mast cell deficiency caused a significant reduction in IL-10, TGF-β, and IL-6 expression in the pancreatic tissue. Interestingly, IL-6-deficient mice are more susceptible to T1D associated with reduced Treg-cell numbers in the PLNs, but mast cell transfer from wild-type mice induced protection to T1D in these mice. Finally, mast cell adoptive transfer prior to MLD-STZ administration conferred resistance to T1D, promoted increased Treg cells, and decreased IL-17-producing T cells in the PLNs. Taken together, our results indicate that mast cells are implicated in resistance to STZ-induced T1D via an immunological tolerance mechanism mediated by Treg cells.

  11. Adding yeasts with sugar to increase the number of effective insecticide classes to manage Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) in cherry

    USDA-ARS?s Scientific Manuscript database

    Drosophila suzukii has become a major pest of fruit crops, including cherry in the western United States. We evaluated whether the addition of sugary baits could improve the efficacy of two classes of insecticides not considered to be sufficiently effective for this pest, diamides and spinosyns, in ...

  12. Characterization of pbt genes conferring increased Pb2+ and Cd2+ tolerance upon Achromobacter xylosoxidans A8.

    PubMed

    Hložková, Kateřina; Suman, Jáchym; Strnad, Hynek; Ruml, Tomas; Paces, Vaclav; Kotrba, Pavel

    2013-12-01

    The cluster of pbtTFYRABC genes is carried by plasmid pA81. Its elimination from Achromobacter xylosoxidans A8 resulted in increased sensitivity towards Pb(2+) and Cd(2+). Predicted pbtTRABC products share strong similarities with Pb(2+) uptake transporter PbrT, transcriptional regulator PbrR, metal efflux P1-ATPases PbrA and CadA, undecaprenyl pyrophosphatase PbrB and its signal peptidase PbrC from Cupriavidus metallidurans CH34. Expression of pbtABC or pbtA in a metal-sensitive Escherichia coli GG48 rendered the strain Pb(2+)-, Cd(2+)- and Zn(2+)-tolerant and caused decreased accumulation of the metal ions. Accumulation of Pb(2+), but not of Cd(2+) or Zn(2+), was promoted in E. coli expressing pbtT. Additional genes of the pbt cluster are pbtF and pbtY, which encode the cation diffusion facilitator (CDF)-like transporter and a putative fatty acid hydroxylase of unknown function, respectively. Expression of pbtF did not confer increased metal tolerance upon E. coli GG48, although the protein showed measurable Pb(2+)-efflux activity. Unlike the pbtT promoter, promoters of pbtABC, pbtF and pbtY contain features characteristic of promoters controlled by metal-responsive transcriptional regulators of the MerR family. Upregulation of pbtABC, pbtF and pbtY upon Pb(2+), Cd(2+) and Zn(2+) exposure was confirmed in wild-type Achromobacter xylosoxidans A8. Gel shift assays proved binding of purified PbtR to the respective promoters. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  13. β-Guanidinopropionic acid extends the lifespan of Drosophila melanogaster via an AMP-activated protein kinase-dependent increase in autophagy.

    PubMed

    Yang, Si; Long, Li-Hong; Li, Di; Zhang, Jian-Kang; Jin, Shan; Wang, Fang; Chen, Jian-Guo

    2015-12-01

    Previous studies have demonstrated that AMP-activated protein kinase (AMPK) controls autophagy through the mammalian target of rapamycin (mTOR) and Unc-51 like kinase 1 (ULK1/Atg1) signaling, which augments the quality of cellular housekeeping, and that β-guanidinopropionic acid (β-GPA), a creatine analog, leads to a chronic activation of AMPK. However, the relationship between β-GPA and aging remains elusive. In this study, we hypothesized that feeding β-GPA to adult Drosophila produces the lifespan extension via activation of AMPK-dependent autophagy. It was found that dietary administration of β-GPA at a concentration higher than 900 mm induced a significant extension of the lifespan of Drosophila melanogaster in repeated experiments. Furthermore, we found that Atg8 protein, the homolog of microtubule-associated protein 1A/1B-light chain 3 (LC3) and a biomarker of autophagy in Drosophila, was significantly upregulated by β-GPA treatment, indicating that autophagic activity plays a role in the effect of β-GPA. On the other hand, when the expression of Atg5 protein, an essential protein for autophagy, was reduced by RNA interference (RNAi), the effect of β-GPA on lifespan extension was abolished. Moreover, we found that AMPK was also involved in this process. β-GPA treatment significantly elevated the expression of phospho-T172-AMPK levels, while inhibition of AMPK by either AMPK-RNAi or compound C significantly attenuated the expression of autophagy-related proteins and lifespan extension in Drosophila. Taken together, our results suggest that β-GPA can induce an extension of the lifespan of Drosophila via AMPK-Atg1-autophagy signaling pathway. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  14. Vitamin E confers cytoprotective effects on cardiomyocytes under conditions of heat stress by increasing the expression of metallothionein.

    PubMed

    Wang, Xiaowu; Dong, Wenpeng; Yuan, Binbin; Yang, Yongchao; Yang, Dongpeng; Lin, Xi; Chen, Changfu; Zhang, Weida

    2016-05-01

    Heat stress (HS) is commonly used to refer to the heat load that an individual is subjected to due to either metabolic heat, or environmental factors, including high temperatures and high humidity levels. HS has been reported to affect and even damage the functioning of various organs; overexposure to high temperatures and high humidity may lead to accidental deaths. It has been suggested that the cardiovascular system is primarily targeted by exposure to HS conditions; the HS-induced dysfunction of cardiomyocytes, which is characterized by mitochondrial dysfunction, may result in the development of cardiovascular diseases. The excessive production of reactive oxygen species (ROS) also participates in mitochondrial dysfunction. However, effective methods for the prevention and treatment of mitochondrial and cardiovascular dysfunction induced by exposure to HS are lacking. In the present study, we hypothesized that vitamin E (VE), an antioxidant, is capable of preventing oxidative stress and mitochondrial injury in cardiomyocytes induced by exposure to HS. The results revealed that pre‑treatment with VE increased the expression of metallothionein (MT), which has previously been reported to confer cytoprotective effects, particularly on the cardiovascular system. Pre-treatment with VE restored mitochondrial function in cardiomyocytes under conditions of HS by increasing the expression of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM), and by increasing adenosine triphosphate (ATP) levels. Furthermore, pre-treatment with VE decreased the production of ROS, which was induced by exposure to HS and thus exerted antioxidant effects. In addition, pre-treatment with VE attenuated oxidative stress induced by exposure to HS, as demonstrated by the increased levels of antioxidant enzymes [superoxide dismutase (SOD) and glutathione (GSH)], and by the decreased levels

  15. Polymorphism of FGFR4 Gly388Arg does not confer an increased risk to breast cancer development.

    PubMed

    Naidu, R; Har, Y C; Taib, N A

    2009-01-01

    The genotype analysis of the Gly and Arg allele at codon 388 of fibroblast growth factor receptor-4 (FGFR4) gene was evaluated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in a hospital-based Malaysian population. Peripheral blood samples were collected from 387 breast cancer patients and 252 normal and healthy women who had no history of any malignancy. The aim of the present study was to evaluate the association between the FGFR4 Gly388Arg polymorphism and breast cancer risk as well as clinicopathological parameters of the patients. The Gly/Gly, Gly/Arg, Arg/Arg, and Arg allele genotypes were detected in 46.3%, 44.4%, 9.3%, and 53.7% of breast cancer cases, respectively. The distribution of genotype (p = 0.204) and allele (p = 0.086) frequencies of FGFR4 polymorphism were not significantly different between the breast cancer cases and normal individuals. Women who were Arg/ Arg homozygotes (OR = 1.714, 95% CI 0.896-3.278), Gly/Arg heterozygotes (OR = 1.205, 95% CI 0.863-1.683), carriers of Arg allele genotype (OR = 1.269, 95% CI 0.921-1.750), or Arg allele (OR = 1.246, 95% CI 0.970-1.602) were not associated with breast cancer risk. The Arg allele genotype was significantly associated with lymph node metastases (p = 0.001) but not with other clinicopathological parameters. Our findings suggest that the polymorphic variant at codon 388 of FGFR4 gene does not confer increased risk to breast cancer development but it may be a potential genetic marker for tumor prognosis.

  16. The serotonin transporter gene polymorphism STin2 VNTR confers an increased risk of inconsistent response to triptans in migraine patients.

    PubMed

    Terrazzino, Salvatore; Viana, Michele; Floriddia, Elisa; Monaco, Francesco; Mittino, Daniela; Sances, Grazia; Tassorelli, Cristina; Nappi, Giuseppe; Rinaldi, Maurizio; Canonico, Pier Luigi; Genazzani, Armando A

    2010-09-01

    The aim of the present observational study was to assess the value of the C825T polymorphism of the beta-3 subunit of G proteins (GNB3) as well as of variants in the SLC6A4 gene (5HTTLPR and STin2 VNTR) and DRD2 gene (TaqI A and NcoI) as predictive markers for consistency in headache response to triptans in migraine patients. Consistent responders to triptans were defined as the migraineurs who experienced a > or =2 point reduction in a 4-point scale intensity of pain from 3 (severe) to 0 (absent) 2h after triptan administration, in at least two attacks out of the three. Genotyping was performed by PCR and PCR-RFLP on genomic DNA extracted from peripheral blood. The impact of clinical and biological variables on consistency status of headache response to triptans was evaluated by using a binary logistic regression model with stepwise selection. Forty-three (33%) of the 130 migraine patients included in the study did not consistently respond to triptan administration. In a binary logistic regression model, STin 2.12/12 genotype (OR=3.363, 95% CI: 1.262-8.966, P=0.005) and non-use of migraine prophylactic medications (OR=2.848, 95% CI: 1.019-7.959, P=0.010) were found as significant factors increasing the odds of achieving inconsistent response to triptans. The analysis of classificatory power of the model showed moderate values of sensitivity (0.56), high specificity (0.87), and an overall prediction correctness (0.77). These results support the role of STin2 VNTR polymorphism of serotonin transporter gene as a relevant genetic factor conferring a higher risk of inconsistent response to triptans in migraine patients. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  17. Patient Participation at Health Care Conferences: Engaged Patients Increase Information Flow, Expand Propagation, and Deepen Engagement in the Conversation of Tweets Compared to Physicians or Researchers

    PubMed Central

    2017-01-01

    Background Health care conferences present a unique opportunity to network, spark innovation, and disseminate novel information to a large audience, but the dissemination of information typically stays within very specific networks. Social network analysis can be adopted to understand the flow of information between virtual social communities and the role of patients within the network. Objective The purpose of this study is to examine the impact engaged patients bring to health care conference social media information flow and how they expand dissemination and distribution of tweets compared to other health care conference stakeholders such as physicians and researchers. Methods From January 2014 through December 2016, 7,644,549 tweets were analyzed from 1672 health care conferences with at least 1000 tweets who had registered in Symplur’s Health Care Hashtag Project from 2014 to 2016. The tweet content was analyzed to create a list of the top 100 influencers by mention from each conference, who were then subsequently categorized by stakeholder group. Multivariate linear regression models were created using stepwise function building to identify factors explaining variability as predictor variables for the model in which conference tweets were taken as the dependent variable. Results Inclusion of engaged patients in health care conference social media was low compared to that of physicians and has not significantly changed over the last 3 years. When engaged patient voices are included in health care conferences, they greatly increase information flow as measured by total tweet volume (beta=301.6) compared to physicians (beta=137.3, P<.001), expand propagation of information tweeted during a conference as measured by social media impressions created (beta=1,700,000) compared to physicians (beta=270,000, P<.001), and deepen engagement in the tweet conversation as measured by replies to their tweets (beta=24.4) compared to physicians (beta=5.5, P<.001). Social

  18. Follow #eHealth2011: Measuring the Role and Effectiveness of Online and Social Media in Increasing the Outreach of a Scientific Conference.

    PubMed

    Winandy, Marcel; Kostkova, Patty; de Quincey, Ed; St Louis, Connie; Szomszor, Martin

    2016-07-19

    Social media promotion is increasingly adopted by organizers of industry and academic events; however, the success of social media strategies is rarely questioned or the real impact scientifically analyzed. We propose a framework that defines and analyses the impact, outreach, and effectiveness of social media for event promotion and research dissemination to participants of a scientific event as well as to the virtual audience through the Web. Online communication channels Twitter, Facebook, Flickr, and a Liveblog were trialed and their impact measured on outreach during five phases of an eHealth conference: the setup, active and last-minute promotion phases before the conference, the actual event, and after the conference. Planned outreach through online channels and social media before and during the event reached an audience several magnitudes larger in size than would have been possible using traditional means. In the particular case of eHealth 2011, the outreach using traditional means would have been 74 attendees plus 23 extra as sold proceedings and the number of downloaded articles from the online proceedings (4107 until October 2013). The audience for the conference reached via online channels and social media was estimated at more than 5300 in total during the event. The role of Twitter for promotion before the event was complemented by an increased usage of the website and Facebook during the event followed by a sharp increase of views of posters on Flickr after the event. Although our case study is focused on a particular audience around eHealth 2011, our framework provides a template for redefining "audience" and outreach of events, merging traditional physical and virtual communities and providing an outline on how these could be successfully reached in clearly defined event phases.

  19. Follow #eHealth2011: Measuring the Role and Effectiveness of Online and Social Media in Increasing the Outreach of a Scientific Conference

    PubMed Central

    Winandy, Marcel; St Louis, Connie; Szomszor, Martin

    2016-01-01

    Background Social media promotion is increasingly adopted by organizers of industry and academic events; however, the success of social media strategies is rarely questioned or the real impact scientifically analyzed. Objective We propose a framework that defines and analyses the impact, outreach, and effectiveness of social media for event promotion and research dissemination to participants of a scientific event as well as to the virtual audience through the Web. Methods Online communication channels Twitter, Facebook, Flickr, and a Liveblog were trialed and their impact measured on outreach during five phases of an eHealth conference: the setup, active and last-minute promotion phases before the conference, the actual event, and after the conference. Results Planned outreach through online channels and social media before and during the event reached an audience several magnitudes larger in size than would have been possible using traditional means. In the particular case of eHealth 2011, the outreach using traditional means would have been 74 attendees plus 23 extra as sold proceedings and the number of downloaded articles from the online proceedings (4107 until October 2013). The audience for the conference reached via online channels and social media was estimated at more than 5300 in total during the event. The role of Twitter for promotion before the event was complemented by an increased usage of the website and Facebook during the event followed by a sharp increase of views of posters on Flickr after the event. Conclusions Although our case study is focused on a particular audience around eHealth 2011, our framework provides a template for redefining “audience” and outreach of events, merging traditional physical and virtual communities and providing an outline on how these could be successfully reached in clearly defined event phases. PMID:27436012

  20. Expression of bovine superoxide dismutase in Drosophila melanogaster augments resistance of oxidative stress.

    PubMed Central

    Reveillaud, I; Niedzwiecki, A; Bensch, K G; Fleming, J E

    1991-01-01

    Superoxide dismutases (SOD) play a major role in the intracellular defense against oxygen radical damage to aerobic cells. In eucaryotes, the cytoplasmic form of the enzyme is a 32-kDa dimer containing two copper and two zinc atoms (CuZn SOD) that catalyzes the dismutation of the superoxide anion (O2-) to H2O2 and O2. Superoxide-mediated damage has been implicated in a number of biological processes, including aging and cancer; however, it is not certain whether endogenously elevated levels of SOD will reduce the pathological events resulting from such damage. To understand the in vivo relationship between an efficient dismutation of O2- and oxidative injury to biological structures, we generated transgenic strains of Drosophila melanogaster overproducing CuZn SOD. This was achieved by microinjecting Drosophila embryos with P-elements containing bovine CuZn SOD cDNA under the control of the Drosophila actin 5c gene promoter. Adult flies of the resulting transformed lines which expressed both mammalian and Drosophila CuZn SOD were then used as a novel model for evaluating the role of oxygen radicals in aging. Our data show that expression of enzymatically active bovine SOD in Drosophila flies confers resistance to paraquat, an O2(-)-generating compound. This is consistent with data on adult mortality, because there was a slight but significant increase in the mean lifespan of several of the transgenic lines. The highest level of expression of the active enzyme in adults was 1.60 times the normal value. Higher levels may have led to the formation of toxic levels of H2O2 during development, since flies that died during the process of eclosion showed an unusual accumulation of lipofuscin (age pigment) in some of their cells. In conclusion, our data show that free-radical detoxification has a minor by positive effect on mean longevity for several strains. Images PMID:1899285

  1. Bitter taste receptors confer diverse functions to neurons

    PubMed Central

    Delventhal, Rebecca; Carlson, John R

    2016-01-01

    Bitter compounds elicit an aversive response. In Drosophila, bitter-sensitive taste neurons coexpress many members of the Gr family of taste receptors. However, the molecular logic of bitter signaling is unknown. We used an in vivo expression approach to analyze the logic of bitter taste signaling. Ectopic or overexpression of bitter Grs increased endogenous responses or conferred novel responses. Surprisingly, expression of Grs also suppressed many endogenous bitter responses. Conversely, deletion of an endogenous Gr led to novel responses. Expression of individual Grs conferred strikingly different effects in different neurons. The results support a model in which bitter Grs interact, exhibiting competition, inhibition, or activation. The results have broad implications for the problem of how taste systems evolve to detect new environmental dangers. DOI: http://dx.doi.org/10.7554/eLife.11181.001 PMID:26880560

  2. Multi-state Comparison of Attractants for Monitoring Drosophila suzukii (Diptera: Drosophilidae) in Blueberries and Caneberries

    USDA-ARS?s Scientific Manuscript database

    Drosophila suzukii, also referred to as the spotted wing drosophila, has recently and dramatically expanded its global range with significant consequences for its primary host crops: blueberries, blackberries, raspberries, cherries, and strawberries. D. suzukii populations can increase quickly, and ...

  3. Transduction in Drosophila olfactory receptor neurons is invariant to air speed

    PubMed Central

    Zhou, Yi

    2012-01-01

    In the vertebrate nose, increasing air speed tends to increase the magnitude of odor-evoked activity in olfactory receptor neurons (ORNs), given constant odor concentration and duration. It is often assumed that the same is true of insect olfactory organs, but this has not been directly tested. In this study, we examined the effect of air speed on ORN responses in Drosophila melanogaster. We constructed an odor delivery device that allowed us to independently vary concentration and air speed, and we used a fast photoionization detector to precisely measure the actual odor concentration at the antenna while simultaneously recording spikes from ORNs in vivo. Our results demonstrate that Drosophila ORN odor responses are invariant to air speed, as long as odor concentration is kept constant. This finding was true across a >100-fold range of air speeds. Because odor hydrophobicity has been proposed to affect the air speed dependence of olfactory transduction, we tested a >1,000-fold range of hydrophobicity values and found that ORN responses are invariant to air speed across this full range. These results have implications for the mechanisms of odor delivery to Drosophila ORNs. Our findings are also significant because flies have a limited ability to control air flow across their antennae, unlike terrestrial vertebrates, which can control air flow within their nasal cavity. Thus, for the fly, invariance to air speed may be adaptive because it confers robustness to changing wind conditions. PMID:22815404

  4. RamA Confers Multidrug Resistance in Salmonella enterica via Increased Expression of acrB, Which Is Inhibited by Chlorpromazine ▿

    PubMed Central

    Bailey, Andrew M.; Paulsen, Ian T.; Piddock, Laura J. V.

    2008-01-01

    Salmonella enterica serovar Typhimurium SL1344, in which efflux pump genes (acrB, acrD, acrF, tolC) or regulatory genes thereof (marA, soxS, ramA) were inactivated, was grown in the presence of 240 antimicrobial and nonantimicrobial agents in the Biolog Phenotype MicroArray. Mutants lacking tolC, acrB, and ramA grew significantly worse than other mutants in the presence of 48 agents (some of which have not previously been identified as substrates of AcrAB-TolC) and particularly poorly in the presence of phenothiazines, which are human antipsychotics. MIC testing revealed that the phenothiazine chlorpromazine had antimicrobial activity and synergized with common antibiotics against different Salmonella serovars and SL1344. Chlorpromazine increased the intracellular accumulation of ethidium bromide, which was ablated in mutants lacking acrB, suggesting an interaction with AcrB. High-level but not low-level overexpression of ramA increased the expression of acrB; conferred resistance to chloramphenicol, tetracycline, nalidixic acid, and triclosan and organic solvent tolerance; and increased the amount of ethidium bromide accumulated. Chlorpromazine induced the modest overproduction of ramA but repressed acrB. These data suggest that phenothiazines are not efflux pump inhibitors but influence gene expression, including that of acrB, which confers the synergy with antimicrobials observed. PMID:18694955

  5. RamA confers multidrug resistance in Salmonella enterica via increased expression of acrB, which is inhibited by chlorpromazine.

    PubMed

    Bailey, Andrew M; Paulsen, Ian T; Piddock, Laura J V

    2008-10-01

    Salmonella enterica serovar Typhimurium SL1344, in which efflux pump genes (acrB, acrD, acrF, tolC) or regulatory genes thereof (marA, soxS, ramA) were inactivated, was grown in the presence of 240 antimicrobial and nonantimicrobial agents in the Biolog Phenotype MicroArray. Mutants lacking tolC, acrB, and ramA grew significantly worse than other mutants in the presence of 48 agents (some of which have not previously been identified as substrates of AcrAB-TolC) and particularly poorly in the presence of phenothiazines, which are human antipsychotics. MIC testing revealed that the phenothiazine chlorpromazine had antimicrobial activity and synergized with common antibiotics against different Salmonella serovars and SL1344. Chlorpromazine increased the intracellular accumulation of ethidium bromide, which was ablated in mutants lacking acrB, suggesting an interaction with AcrB. High-level but not low-level overexpression of ramA increased the expression of acrB; conferred resistance to chloramphenicol, tetracycline, nalidixic acid, and triclosan and organic solvent tolerance; and increased the amount of ethidium bromide accumulated. Chlorpromazine induced the modest overproduction of ramA but repressed acrB. These data suggest that phenothiazines are not efflux pump inhibitors but influence gene expression, including that of acrB, which confers the synergy with antimicrobials observed.

  6. Does Older Age Confer an Increased Risk of Incident Neurocognitive Disorders Among Persons Living with HIV Disease?

    PubMed Central

    Sheppard, David P.; Woods, Steven Paul; Bondi, Mark W.; Gilbert, Paul E.; Massman, Paul J.; Doyle, Katie L.

    2015-01-01

    Objective This study aimed to determine the combined effects of age and HIV infection on the risk of incident neurocognitive disorders. Method A total of 146 neurocognitively normal participants were enrolled at baseline into one of four groups based on age (≤ 40 years and ≥ 50 years) and HIV serostatus resulting in 24 younger HIV−, 27 younger HIV+, 39 older HIV−, and 56 older HIV+ individuals. All participants were administered a standardized clinical neuropsychological battery at baseline and 14.3 ±0.2 months later. Results A logistic regression predicting incident neurocognitive disorders from HIV, age group, and their interaction was significant (χ2[4] = 13.56, p = .009), with a significant main effect of HIV serostatus (χ2[1] = 5.01, p = .025), but no main effect of age or age by HIV interaction (ps > .10). Specifically, 15.7 percent of the HIV+ individuals had an incident neurocognitive disorder as compared to 3.2 percent of the HIV− group (odds ratio = 4.8 [1.2, 32.6]). Among older HIV+ adults, lower baseline cognitive reserve, prospective memory, and verbal fluency each predicted incident neurocognitive disorders at follow-up. Conclusions Independent of age, HIV infection confers a nearly 5-fold risk for developing a neurocognitive disorder over approximately one year. Individuals with lower cognitive reserve and mild weaknesses in higher-order neurocognitive functions may be targeted for closer clinical monitoring and preventative measures. PMID:26367342

  7. Overexpression of the yeast transcription activator Msn2 confers furfural resistance and increases the initial fermentation rate in ethanol production.

    PubMed

    Sasano, Yu; Watanabe, Daisuke; Ukibe, Ken; Inai, Tomomi; Ohtsu, Iwao; Shimoi, Hitoshi; Takagi, Hiroshi

    2012-04-01

    Lignocellulosic biomass is a promising source for bioethanol production, because it is abundant worldwide and has few competing uses. However, the treatment of lignocelllulosic biomass with weak acid to release cellulose and hemicellulose generates many kinds of byproducts including furfural and 5-hydroxymethylfurfural, which inhibit fermentation by yeast, because they generate reactive oxygen species (ROS) in cells. In order to acquire high tolerance to oxidative stress in bioethanol yeast strains, we focused on the transcription activator Msn2 of Saccharomyces cerevisiae, which regulates numerous genes involved in antioxidative stress responses, and constructed bioethanol yeast strains that overexpress Msn2 constitutively. The Msn2-overexpressing bioethanol strains showed tolerance to oxidative stress, probably due to the high-level expression of various antioxidant enzyme genes. Unexpectedly, these strains showed ethanol sensitivity compared with the control strain, probably due to imbalance of the expression level between Msn2 and Msn4. In the presence of furfural, the engineered strains exhibited reduced intracellular ROS levels, and showed rapid growth compared with the control strain. The fermentation test in the presence of furfural revealed that the Msn2-overexpressing strains showed improvement of the initial rate of fermentation. Our results indicate that overexpression of the transcription activator Msn2 in bioethanol yeast strains confers furfural tolerance by reducing the intracellular ROS levels and enhances the initial rate of fermentation in the presence of furfural, suggesting that these strains are capable of adapting rapidly to various compounds that inhibit fermentation by inducing ROS accumulation. Our results not only promise to improve bioethanol production from lignocellulosic biomass, but also provide novel insights for molecular breeding of industrial yeast strains.

  8. Spiroplasma Bacteria Enhance Survival of Drosophila hydei Attacked by the Parasitic Wasp Leptopilina heterotoma

    PubMed Central

    Xie, Jialei; Vilchez, Igor; Mateos, Mariana

    2010-01-01

    Background Maternally-transmitted associations between endosymbiotic bacteria and insects are ubiquitous. While many of these associations are obligate and mutually beneficial, many are facultative, and the mechanism(s) by which these microbes persist in their host lineages remain elusive. Inherited microbes with imperfect transmission are expected to be lost from their host lineages if no other mechanisms increase their persistence (i.e., host reproductive manipulation and/or fitness benefits to host). Indeed numerous facultative heritable endosymbionts are reproductive manipulators. Nevertheless, many do not manipulate reproduction, so they are expected to confer fitness benefits to their hosts, as has been shown in several studies that report defense against natural enemies, tolerance to environmental stress, and increased fecundity. Methodology/Principal Findings We examined whether larval to adult survival of Drosophila hydei against attack by a common parasitoid wasp (Leptopilina heterotoma), differed between uninfected flies and flies that were artificially infected with Spiroplasma, a heritable endosymbiont of Drosophila hydei that does not appear to manipulate host reproduction. Survival was significantly greater for Spiroplasma-infected flies, and the effect of Spiroplasma infection was most evident during the host's pupal stage. We examined whether or not increased survival of Spiroplasma-infected flies was due to reduced oviposition by the wasp (i.e., pre-oviposition mechanism). The number of wasp eggs per fly larva did not differ significantly between Spiroplasma-free and Spiroplasma-infected fly larvae, suggesting that differential fly survival is due to a post-oviposition mechanism. Conclusions/Significance Our results suggest that Spiroplasma confers protection to D. hydei against wasp parasitism. This is to our knowledge the first report of a potential defensive mutualism in the genus Spiroplasma. Whether it explains the persistence and high

  9. Dmp53, basket and drICE gene knockdown and polyphenol gallic acid increase life span and locomotor activity in a Drosophila Parkinson’s disease model

    PubMed Central

    Ortega-Arellano, Hector Flavio; Jimenez-Del-Rio, Marlene; Velez-Pardo, Carlos

    2013-01-01

    Understanding the mechanism(s) by which dopaminergic (DAergic) neurons are eroded in Parkinson’s disease (PD) is critical for effective therapeutic strategies. By using the binary tyrosine hydroxylase (TH)-Gal4/UAS-X RNAi Drosophila melanogaster system, we report that Dmp53, basket and drICE gene knockdown in dopaminergic neurons prolong life span (p < 0.05; log-rank test) and locomotor activity (p < 0.05; χ2 test) in D. melanogaster lines chronically exposed to (1 mM) paraquat (PQ, oxidative stress (OS) generator) compared to untreated transgenic fly lines. Likewise, knockdown flies displayed higher climbing performance than control flies. Amazingly, gallic acid (GA) significantly protected DAergic neurons, ameliorated life span, and climbing abilities in knockdown fly lines treated with PQ compared to flies treated with PQ only. Therefore, silencing specific gene(s) involved in neuronal death might constitute an excellent tool to study the response of DAergic neurons to OS stimuli. We propose that a therapy with antioxidants and selectively “switching off” death genes in DAergic neurons could provide a means for pre-clinical PD individuals to significantly ameliorate their disease condition. PMID:24385865

  10. Familial Amyotrophic Lateral Sclerosis-linked Mutations in Profilin 1 Exacerbate TDP-43-induced Degeneration in the Retina of Drosophila melanogaster through an Increase in the Cytoplasmic Localization of TDP-43.

    PubMed

    Matsukawa, Koji; Hashimoto, Tadafumi; Matsumoto, Taisei; Ihara, Ryoko; Chihara, Takahiro; Miura, Masayuki; Wakabayashi, Tomoko; Iwatsubo, Takeshi

    2016-11-04

    Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive and selective loss of motor neurons. Causative genes for familial ALS (fALS), e.g. TARDBP or FUS/TLS, have been found, among which mutations within the profilin 1 (PFN1) gene have recently been identified in ALS18. To elucidate the mechanism whereby PFN1 mutations lead to neuronal death, we generated transgenic Drosophila melanogaster overexpressing human PFN1 in the retinal photoreceptor neurons. Overexpression of wild-type or fALS mutant PFN1 caused no degenerative phenotypes in the retina. Double overexpression of fALS mutant PFN1 and human TDP-43 markedly exacerbated the TDP-43-induced retinal degeneration, i.e. vacuolation and thinning of the retina, whereas co-expression of wild-type PFN1 did not aggravate the degenerative phenotype. Notably, co-expression of TDP-43 with fALS mutant PFN1 increased the cytoplasmic localization of TDP-43, the latter remaining in nuclei upon co-expression with wild-type PFN1, whereas co-expression of TDP-43 lacking the nuclear localization signal with the fALS mutant PFN1 did not aggravate the retinal degeneration. Knockdown of endogenous Drosophila PFN1 did not alter the degenerative phenotypes of the retina in flies overexpressing wild-type TDP-43 These data suggest that ALS-linked PFN1 mutations exacerbate TDP-43-induced neurodegeneration in a gain-of-function manner, possibly by shifting the localization of TDP-43 from nuclei to cytoplasm. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Conference report on tobacco taxes in Central America: current situation and opportunities to reduce prevalence and increase fiscal revenues.

    PubMed

    Garcés, Ana; Garcés, Miguel; Barnoya, Joaquin; Cabrera, Maynor; Sandoval, Rosa; Orozco, Juan Guillermo; Chaloupka, Frank J

    2014-01-01

    As stated in Article 6 of Framework Convention on Tobacco Control (FCTC), increasing tobacco prices through higher taxes is one of the most effective interventions to reduce tobacco use and to encourage smokers to quit. The potential for tax increases on tobacco products in Central America is ample. We aim to synthesize the current tobacco taxes situation and highlight research needs to strengthen taxation. In May 2012, a workshop was carried out with representatives from each Central American country to analyze the tobacco tax situation in each country and to identify key research gaps with experts in the field. Tobacco taxes in Central America fall far short of the levels recommended by FCTC. Moreover, the legal framework is complex and creates barriers for higher taxes that require further research and political will. Top research priorities are an in-depth analysis of tobacco tax legislation, impact of tax and price policies, analysis of costs associated to health care of tobacco-related diseases and lost productivity, and the feasibility of approaches to increasing tobacco taxes in certain contexts. An additional area of research is the interrelationship between human rights and tobacco control. Central American countries would benefit from increasing excise taxes on tobacco products. The lack of available data and research to counteract tobacco industry arguments are significant obstacles. Active leadership of civil society in support of the partnership of chronic disease interventions is vital in order to obtain tax increases on tobacco products.

  12. Registration of Common Wheat Germplasm with Mutations in SBEII Genes Conferring Increased Grain Amylose and Resistant Starch Content

    PubMed Central

    Schönhofen, André; Hazard, Brittany; Zhang, Xiaoqin; Dubcovsky, Jorge

    2016-01-01

    Starch present in the endosperm of common wheat (Triticum aestivum L.) grains is an important source of carbohydrates worldwide. Starches with a greater proportion of amylose have increased levels of resistant starch, a dietary fiber that can provide human health benefits. Induced mutations in STARCH BRANCHING ENZYME II (SBEII) genes in wheat are associated with increased amylose and resistant starch. Ethyl methane sulfonate mutations in SBEIIa and SBEIIb paralogs were combined in the hexaploid wheat cultivar Lassik. Four mutant combinations were generated: SBEIIa/b-AB (Reg. No. GP-997, PI 675644); SBEIIa/b-A, SBEIIa-D (Reg. No. GP-998, PI 675645); SBEIIa/b-B, SBEIIa-D (Reg. No. GP-999, PI 675646); and SBEIIa/b-AB, SBEIIa-D (Reg. No. GP-1000, PI 675647). The SBEII mutant lines were compared with a wild-type control in a greenhouse and field experiment. The quintuple mutant line (SBEIIa/b-AB, SBEIIa-D) presented significant increases in both amylose (51% greenhouse; 63% field) and resistant starch (947% greenhouse; 1057% field) relative to the control. A decrease in total starch content (7.8%) was observed in the field experiment. The quintuple mutant also differed in starch viscosity parameters. Registration of the hexaploid wheat SBEII-mutant lines by University of California, Davis can help expedite the development of common wheat cultivars with increased amylose and resistant starch content. PMID:27818720

  13. Cold acclimation alters DNA methylation patterns and confers tolerance to heat and increases growth rate in Brassica rapa

    PubMed Central

    Liu, Tongkun; Li, Ying; Duan, Weike; Huang, Feiyi

    2017-01-01

    Abstract Epigenetic modifications are implicated in plant adaptations to abiotic stresses. Exposure of plants to one stress can induce resistance to other stresses, a process termed cross-adaptation, which is not well understood. In this study, we aimed to unravel the epigenetic basis of elevated heat-tolerance in cold-acclimated Brassica rapa by conducting a genome-wide DNA methylation analysis of leaves from control (CK) and cold-acclimated (CA) plants. We found that both methylation and demethylation occurred during cold acclimation. Two significantly altered pathways, malate dehydrogenase activity and carbon fixation, and 1562 differentially methylated genes, including BramMDH1, BraKAT2, BraSHM4, and Bra4CL2, were identified in CA plants. Genetic validation and treatment of B. rapa with 5-aza-2-deoxycytidine (Aza) suggested that promoter demethylation of four candidate genes increased their transcriptional activities. Physiological analysis suggested that elevated heat-tolerance and high growth rate were closely related to increases in organic acids and photosynthesis, respectively. Functional analyses demonstrated that the candidate gene BramMDH1 (mMDH: mitochondrial malate dehydrogenase) directly enhances organic acids and photosynthesis to increase heat-tolerance and growth rate in Arabidopsis. However, Aza-treated B. rapa, which also has elevated BramMDH1 levels, did not exhibit enhanced heat-tolerance. We therefore suggest that DNA demethylation alone is not sufficient to increase heat-tolerance. This study demonstrates that altered DNA methylation contributes to cross-adaptation. PMID:28158841

  14. Overexpression of AtCPS and AtKS in Arabidopsis confers increased ent-kaurene production but no increase in bioactive gibberellins.

    PubMed

    Fleet, Christine M; Yamaguchi, Shinjiro; Hanada, Atsushi; Kawaide, Hiroshi; David, Charles J; Kamiya, Yuji; Sun, Tai-Ping

    2003-06-01

    The plant growth hormone gibberellin (GA) is important for many aspects of plant growth and development. Although most genes encoding enzymes at each step of the GA biosynthetic pathway have been cloned, their regulation is less well understood. To assess how up-regulation of early steps affects the biosynthetic pathway overall, we have examined transgenic Arabidopsis plants that overexpress either AtCPS or AtKS or both. These genes encode the enzymes ent-copalyl diphosphate synthase (CPS) and ent-kaurene synthase, which catalyze the first two committed steps in GA biosynthesis. We find that both CPS and CPS/ent-kaurene synthase overexpressors have greatly increased levels of the early intermediates ent-kaurene and ent-kaurenoic acid, but a lesser increase of later metabolites. These overexpression lines do not exhibit any GA overdose morphology and have wild-type levels of bioactive GAs. Our data show that CPS is limiting for ent-kaurene production and suggest that conversion of ent-kaurenoic acid to GA12 by ent-kaurenoic acid oxidase may be an important rate-limiting step for production of bioactive GA. These results demonstrate the ability of plants to maintain GA homeostasis despite large changes in accumulation of early intermediates in the biosynthetic pathway.

  15. Using an ACTIVE teaching format versus a standard lecture format for increasing resident interaction and knowledge achievement during noon conference: a prospective, controlled study

    PubMed Central

    2014-01-01

    Background The traditional lecture is used by many residency programs to fulfill the mandate for regular didactic sessions, despite limited evidence to demonstrate its effectiveness. Active teaching strategies have shown promise in improving medical knowledge but have been challenging to implement within the constraints of residency training. We developed and evaluated an innovative structured format for interactive teaching within the residency noon conference. Methods We developed an ACTIVE teaching format structured around the following steps: assemble (A) into groups, convey (C) learning objectives, teach (T) background information, inquire (I) through cases and questions, verify (V) understanding, and explain (E) answer choices and educate on the learning points. We conducted a prospective, controlled study of the ACTIVE teaching format versus the standard lecture format, comparing resident satisfaction, immediate knowledge achievement and long-term knowledge retention. We qualitatively assessed participating faculty members’ perspectives on the faculty development efforts and the feasibility of teaching using the ACTIVE format. Results Sixty-nine internal medicine residents participated in the study. Overall, there was an improvement in perceived engagement using the ACTIVE teaching format (4.78 vs. 3.80, P < 0.01), with no increase in stress or decrement in break time. There was an improvement in initial knowledge achievement with the ACTIVE teaching format (overall absolute score increase of 11%, P = 0.04) and a trend toward improvement in long-term knowledge retention. Faculty members felt adequately prepared to use the ACTIVE teaching format, and enjoyed teaching with the ACTIVE teaching format more than the standard lecture. Conclusions A structured ACTIVE teaching format improved resident engagement and initial knowledge, and required minimal resources. The ACTIVE teaching format offers an exciting alternative to the standard lecture for

  16. Using an ACTIVE teaching format versus a standard lecture format for increasing resident interaction and knowledge achievement during noon conference: a prospective, controlled study.

    PubMed

    Sawatsky, Adam P; Berlacher, Kathryn; Granieri, Rosanne

    2014-07-01

    The traditional lecture is used by many residency programs to fulfill the mandate for regular didactic sessions, despite limited evidence to demonstrate its effectiveness. Active teaching strategies have shown promise in improving medical knowledge but have been challenging to implement within the constraints of residency training. We developed and evaluated an innovative structured format for interactive teaching within the residency noon conference. We developed an ACTIVE teaching format structured around the following steps: assemble (A) into groups, convey (C) learning objectives, teach (T) background information, inquire (I) through cases and questions, verify (V) understanding, and explain (E) answer choices and educate on the learning points. We conducted a prospective, controlled study of the ACTIVE teaching format versus the standard lecture format, comparing resident satisfaction, immediate knowledge achievement and long-term knowledge retention. We qualitatively assessed participating faculty members' perspectives on the faculty development efforts and the feasibility of teaching using the ACTIVE format. Sixty-nine internal medicine residents participated in the study. Overall, there was an improvement in perceived engagement using the ACTIVE teaching format (4.78 vs. 3.80, P < 0.01), with no increase in stress or decrement in break time. There was an improvement in initial knowledge achievement with the ACTIVE teaching format (overall absolute score increase of 11%, P = 0.04) and a trend toward improvement in long-term knowledge retention. Faculty members felt adequately prepared to use the ACTIVE teaching format, and enjoyed teaching with the ACTIVE teaching format more than the standard lecture. A structured ACTIVE teaching format improved resident engagement and initial knowledge, and required minimal resources. The ACTIVE teaching format offers an exciting alternative to the standard lecture for resident noon conference and is easy to implement.

  17. Novel Barley (1→3,1→4)-β-Glucan Endohydrolase Alleles Confer Increased Enzyme Thermostability.

    PubMed

    Lauer, Juanita C; Yap, Kuok; Cu, Suong; Burton, Rachel A; Eglinton, Jason K

    2017-01-18

    Barley (1→3,1→4)-β-glucan endohydrolases (β-glucanases; EI and EII) are primarily responsible for hydrolyzing high molecular weight (1→3,1→4)-β-glucans (β-glucan) during germination. Incomplete endosperm modification during malting results in residual β-glucan that can contribute to increased wort viscosity and beer chill haze. Four newly identified forms of EI and EII and the reference enzymes EI-a and EII-a were expressed in Escherichia coli, and the recombinant proteins were characterized for enzyme kinetics and thermostability. EI and EII variants that exhibited higher residual β-glucanase activity than EI-a and EII-a after heat treatment also exhibited increased substrate affinity and decreased turnover rates. The novel EII-l form exhibited significantly increased thermostability compared with the reference EII-a when activity was measured at elevated temperature. EII-l exhibited a T50 value, which indicates the temperature at which 50% of β-glucanase activity remains, 1.3 °C higher than that of EII-a. The irreversible thermal inactivation difference between EII-a and EII-l after 5 min of heat treatment at 56 °C was 11.9%. The functional significance of the three amino acid differences between EII-a and EII-l was examined by making combinatorial mutations in EII-a using site-directed mutagenesis. The S20G and D284E amino acid substitutions were shown to be responsible for the increase in EII-1 thermostability.

  18. Heterologous expression of chloroplast-localized geranylgeranyl pyrophosphate synthase confers fast plant growth, early flowering and increased seed yield.

    PubMed

    Tata, Sandeep Kumar; Jung, Jihye; Kim, Yoon-Ha; Choi, Jun Young; Jung, Ji-Yul; Lee, In-Jung; Shin, Jeong Sheop; Ryu, Stephen Beungtae

    2016-01-01

    Geranylgeranyl pyrophosphate synthase (GGPS) is a key enzyme for a structurally diverse class of isoprenoid biosynthetic metabolites including gibberellins, carotenoids, chlorophylls and rubber. We expressed a chloroplast-targeted GGPS isolated from sunflower (Helianthus annuus) under control of the cauliflower mosaic virus 35S promoter in tobacco (Nicotiana tabacum). The resulting transgenic tobacco plants expressing heterologous GGPS showed remarkably enhanced growth (an increase in shoot and root biomass and height), early flowering, increased number of seed pods and greater seed yield compared with that of GUS-transgenic lines (control) or wild-type plants. The gibberellin levels in HaGGPS-transgenic plants were higher than those in control plants, indicating that the observed phenotype may result from increased gibberellin content. However, in HaGGPS-transformant tobacco plants, we did not observe the phenotypic defects such as reduced chlorophyll content and greater petiole and stalk length, which were previously reported for transgenic plants expressing gibberellin biosynthetic genes. Fast plant growth was also observed in HaGGPS-expressing Arabidopsis and dandelion plants. The results of this study suggest that GGPS expression in crop plants may yield desirable agronomic traits, including enhanced growth of shoots and roots, early flowering, greater numbers of seed pods and/or higher seed yield. This research has potential applications for fast production of plant biomass that provides commercially valuable biomaterials or bioenergy. © 2015 Korea Research Institute of Bioscience & Biotechnology. Plant Biotechnology Journal published by John Wiley & Sons Ltd and Society for Experimental Biology, Association of Applied Biologists.

  19. The Drosophila visual system

    PubMed Central

    Zhu, Yan

    2013-01-01

    A compact genome and a tiny brain make Drosophila the prime model to understand the neural substrate of behavior. The neurogenetic efforts to reveal neural circuits underlying Drosophila vision started about half a century ago, and now the field is booming with sophisticated genetic tools, rich behavioral assays, and importantly, a greater number of scientists joining from different backgrounds. This review will briefly cover the structural anatomy of the Drosophila visual system, the animal’s visual behaviors, the genes involved in assembling these circuits, the new and powerful techniques, and the challenges ahead for ultimately identifying the general principles of biological computation in the brain.   A typical brain utilizes a great many compact neural circuits to collect and process information from the internal biological and external environmental worlds and generates motor commands for observable behaviors. The fruit fly Drosophila melanogaster, despite of its miniature body and tiny brain, can survive in almost any corner of the world.1 It can find food, court mate, fight rival conspecific, avoid predators, and amazingly fly without crashing into trees. Drosophila vision and its underlying neuronal machinery has been a key research model for at least half century for neurogeneticists.2 Given the efforts invested on the visual system, this animal model is likely to offer the first full understanding of how visual information is computed by a multi-cellular organism. Furthermore, research in Drosophila has revealed many genes that play crucial roles in the formation of functional brains across species. The architectural similarities between the visual systems of Drosophila and vertebrate at the molecular, cellular, and network levels suggest new principles discovered at the circuit level on the relationship between neurons and behavior in Drosophila shall also contribute greatly to our understanding of the general principles for how bigger brains work.3

  20. Inhibition of TRPV1 confers neuroprotection, reduces TNF-α and increases Il-10 in a rat stroke model.

    PubMed

    Hakimizadeh, Elham; Shamsizadeh, Ali; Roohbakhsh, Ali; Arababadi, Mohammad Kazemi; Hajizadeh, Mohammad Reza; Shariati, Mehdi; Rahmani, Mohammad Reza; Allahtavakoli, Mohammad

    2017-02-15

    Stroke is a major cause of mortality and long-term disability in adults. TRPV1 plays a crucial role in neuroinflammation. In the current study, the effects of TRPV1 agonist (capsaicin) and antagonist (AMG9810) on cerebral ischemia were investigated. Forty male Wistar rats were assigned to the following experimental groups: sham, vehicle) ischemic), AMG9810 (selective TRPV1 antagonist, 0.5 mg/kg; 3 h after stroke), and capsaicin (1 mg/kg; 3 h after stroke). Stroke was induced by permanent middle cerebral artery occlusion and neurological deficits were evaluated 1, 3, and 7 days after stroke. Then, infarct volume, brain edema, body temperature, mRNA expression of TRPV1 and serum concentrations of TNF-α and IL-10 were measured. Compared to the vehicle group, AMG9810 significantly decreased the infarct volume (P< 0.01). Latency for the removal of sticky labels from the forepaw and the hanging time were significantly decreased and increased respectively following administration of AMG9810 (P< 0.01 and P< 0.001 versus vehicle) 3 and 7 days after stroke. Compared to the sham group, the mRNA expression of TRPV1 was significantly increased in vehicle group (P< 0.01). Administration of AMG9810 significantly increased the anti-inflammatory cytokine IL-10 and decreased the inflammatory cytokine TNF-α (P< 0.05). Moreover, our results indicate that AMG9810 might a promising candidate for the hypothermic treatment of stroke. The findings also suggest a key role for AMG9810 in reducing inflammation after stroke and imply that TRPV1 could be a potential target for the treatment of ischemic stroke. This article is protected by copyright. All rights reserved.

  1. Mouse Model of OPRM1 (A118G) Polymorphism Increases Sociability and Dominance and Confers Resilience to Social Defeat

    PubMed Central

    Briand, Lisa A.; Hilario, Monica; Dow, Holly C.; Brodkin, Edward S.; Berton, Olivier

    2015-01-01

    A single nucleotide polymorphism (SNP) in the human μ-opioid receptor gene (OPRM1 A118G) has been widely studied for its association in drug addiction, pain sensitivity, and, more recently, social behavior. The endogenous opioid system has been shown to regulate social distress and reward in a variety of animal models. However, mechanisms underlying the associations between the OPRM1 A118G SNP and these behaviors have not been clarified. We used a mouse model possessing the human equivalent nucleotide/amino acid substitution to study social affiliation and social defeat behaviors. In mice with the Oprm1 A112G SNP, we demonstrate that the G allele is associated with an increase in home-cage dominance and increased motivation for nonaggressive social interactions, similar to what is reported in human populations. When challenged by a resident aggressor, G-allele carriers expressed less submissive behavior and exhibited resilience to social defeat, demonstrated by a lack of subsequent social avoidance and reductions in anhedonia as measured by intracranial self-stimulation. Protection from social defeat in G-allele carriers was associated with a greater induction of c-fos in a resilience circuit comprising the nucleus accumbens and periaqueductal gray. These findings led us to test the role of endogenous opioids in the A112G mice. We demonstrate that the increase in social affiliation in G carriers is blocked by pretreatment with naloxone. Together, these data suggest a mechanism involving altered hedonic state and neural activation as well as altered endogenous opioid tone in the differential response to aversive and rewarding social stimuli in G-allele carriers. PMID:25716856

  2. Mouse model of OPRM1 (A118G) polymorphism increases sociability and dominance and confers resilience to social defeat.

    PubMed

    Briand, Lisa A; Hilario, Monica; Dow, Holly C; Brodkin, Edward S; Blendy, Julie A; Berton, Olivier

    2015-02-25

    A single nucleotide polymorphism (SNP) in the human μ-opioid receptor gene (OPRM1 A118G) has been widely studied for its association in drug addiction, pain sensitivity, and, more recently, social behavior. The endogenous opioid system has been shown to regulate social distress and reward in a variety of animal models. However, mechanisms underlying the associations between the OPRM1 A118G SNP and these behaviors have not been clarified. We used a mouse model possessing the human equivalent nucleotide/amino acid substitution to study social affiliation and social defeat behaviors. In mice with the Oprm1 A112G SNP, we demonstrate that the G allele is associated with an increase in home-cage dominance and increased motivation for nonaggressive social interactions, similar to what is reported in human populations. When challenged by a resident aggressor, G-allele carriers expressed less submissive behavior and exhibited resilience to social defeat, demonstrated by a lack of subsequent social avoidance and reductions in anhedonia as measured by intracranial self-stimulation. Protection from social defeat in G-allele carriers was associated with a greater induction of c-fos in a resilience circuit comprising the nucleus accumbens and periaqueductal gray. These findings led us to test the role of endogenous opioids in the A112G mice. We demonstrate that the increase in social affiliation in G carriers is blocked by pretreatment with naloxone. Together, these data suggest a mechanism involving altered hedonic state and neural activation as well as altered endogenous opioid tone in the differential response to aversive and rewarding social stimuli in G-allele carriers.

  3. Dysfunctional Pro-Inflammatory High Density Lipoproteins Confer Increased Risk for Atherosclerosis in Women with Systemic Lupus Erythematosus

    PubMed Central

    McMahon, Maureen; Grossman, Jennifer; Skaggs, Brian; FitzGerald, John; Sahakian, Lori; Ragavendra, Nagesh; Charles-Schoeman, Christina; Watson, Karol; Wong, Weng Kee; Chen, Weiling; Gorn, Alan; Karpouzas, George; Weisman, Michael; Wallace, Daniel J.; Hahn, Bevra H.

    2009-01-01

    Objective Women with systemic lupus erythematosus (SLE) have increased atherosclerosis. Identification of at-risk patients and the etiology underlying atherosclerosis in SLE remains elusive. Normal HDL lose antioxidant capacity during inflammation, and these dysfunctional HDL might predispose to atherosclerosis. The aim of this study is to determine whether dysfunctional pro-inflammatory HDL (piHDL) is associated with subclinical atherosclerosis in SLE. Methods 276 SLE women had carotid artery ultrasound to identify plaques and measure intima-media thickness (IMT). Antioxidant function of HDL was measured as change in oxidation of LDL after addition of subject HDL. Two anti-inflammatory HDL components, paraoxonase and apolipoprotein A-1, were also measured. Results 48.2% of patients had piHDL. 86.7% of subjects with plaque had piHDL, versus 40.7% without (p<0.001). Patients with piHDL also had higher IMT (p<0.001). After multivariate analysis, the only significant factors associated with plaque were piHDL, (OR 16.1, p<0.001), age (OR 1.2, p<0.001), hypertension (OR 3.0, p=0.04), dyslipidemia (OR 3.4, p=0.04), and mixed racial background (OR 8.3, p=0.04). Factors associated with IMT measurements in the highest quartile were piHDL (OR 2.5, p=0.02), age (OR 1.1, p<0.001), body mass index (OR 1.07, p=0.04), lifetime prednisone dose > 20g (OR 2.8, p=0.04), and African American race (OR 8.3, p=0.001). Conclusions Dysfunctional piHDL greatly increases risk for subclinical atherosclerosis in SLE; they associate with increased prevalence of carotid plaque and with high IMT. The presence of piHDL may help identify patients at risk for atherosclerosis. PMID:19644959

  4. Registration of Durum Wheat Germplasm Lines with Combined Mutations in SBEIIa and SBEIIb Genes Conferring Increased Amylose and Resistant Starch.

    PubMed

    Hazard, Brittany; Zhang, Xiaoqin; Naemeh, Mahmoudreza; Dubcovsky, Jorge

    2014-08-25

    Durum wheat [Triticum turgidum L. subsp. durum (Desf.) Husn.], used in pasta, couscous, and flatbread production, is an important source of starch food products worldwide. The amylose portion of the starch forms resistant starch complexes that resist digestion and contribute to dietary fiber. Increasing the amount of amylose and resistant starch in wheat by mutating the STARCH BRANCHING ENZYME II (SBEII) genes has potential to provide human health benefits. Ethyl methane sulfonate mutations in the linked SBEIIa and SBEIIb paralogs were combined on chromosomes 2A (SBEIIa/b-A; Reg. No. GP-968, PI 670159), 2B (SBEIIa/b-B; Reg. No. GP-970, PI 670161), and on both chromosomes (SBEIIa/b-AB; Reg. No. GP-969, PI 670160) in the tetraploid wheat cultivar Kronos, a semidwarf durum wheat cultivar that has high yield potential and excellent pasta quality. These three double and quadruple SBEII-mutant lines were compared with a control sib line with no SBEII mutations in two field locations in California. The SBEIIa/b-AB line with four mutations showed dramatic increases in amylose (average 66%) and resistant starch (average 753%) relative to the control. However, the SBEIIa/b-AB line also showed an average 7% decrease in total starch and an 8% decrease in kernel weight. The release by the University of California-Davis of the durum wheat germplasm combining four SBEIIa and SBEIIb mutations will accelerate the deployment of these mutations in durum wheat breeding programs and the development of durum wheat varieties with increased resistant starch.

  5. Registration of Durum Wheat Germplasm Lines with Combined Mutations in SBEIIa and SBEIIb Genes Conferring Increased Amylose and Resistant Starch

    PubMed Central

    Hazard, Brittany; Zhang, Xiaoqin; Naemeh, Mahmoudreza; Dubcovsky, Jorge

    2016-01-01

    Durum wheat [Triticum turgidum L. subsp. durum (Desf.) Husn.], used in pasta, couscous, and flatbread production, is an important source of starch food products worldwide. The amylose portion of the starch forms resistant starch complexes that resist digestion and contribute to dietary fiber. Increasing the amount of amylose and resistant starch in wheat by mutating the STARCH BRANCHING ENZYME II (SBEII) genes has potential to provide human health benefits. Ethyl methane sulfonate mutations in the linked SBEIIa and SBEIIb paralogs were combined on chromosomes 2A (SBEIIa/b-A; Reg. No. GP-968, PI 670159), 2B (SBEIIa/b-B; Reg. No. GP-970, PI 670161), and on both chromosomes (SBEIIa/b-AB; Reg. No. GP-969, PI 670160) in the tetraploid wheat cultivar Kronos, a semidwarf durum wheat cultivar that has high yield potential and excellent pasta quality. These three double and quadruple SBEII-mutant lines were compared with a control sib line with no SBEII mutations in two field locations in California. The SBEIIa/b-AB line with four mutations showed dramatic increases in amylose (average 66%) and resistant starch (average 753%) relative to the control. However, the SBEIIa/b-AB line also showed an average 7% decrease in total starch and an 8% decrease in kernel weight. The release by the University of California–Davis of the durum wheat germplasm combining four SBEIIa and SBEIIb mutations will accelerate the deployment of these mutations in durum wheat breeding programs and the development of durum wheat varieties with increased resistant starch. PMID:27110322

  6. Drosophila Blastorderm Analysis Software

    SciTech Connect

    2006-10-25

    PointCloudMake analyzes 3D fluorescent images of whole Drosophila embryo and produces a table-style "PointCloud" file which contains the coordinates and volumes of all the nuclei, cells, their associated relative gene expression levels along with morphological features of the embryo. See: Luengo Hendrix et at 2006 3D Morphology and Gene Expression in the Drosophila Blastoderm at Cellular Resolution manuscript submitted LBNL # LBNL-60178 Knowles DW, Keranen SVE, Biggin M. Sudar S (2002) Mapping organism expression levels at cellular resolution in developing Drosophila. In: Conchello JA, Cogswell CJ, Wilson T, editors. Three-Dimensional and Multidimensional Microscopy: Image Acquisition and Processing IX. pp. 57-64

  7. Overexpression of an Apocynum venetum DEAD-Box Helicase Gene (AvDH1) in Cotton Confers Salinity Tolerance and Increases Yield in a Saline Field

    PubMed Central

    Chen, Jie; Wan, Sibao; Liu, Huaihua; Fan, Shuli; Zhang, Yujuan; Wang, Wei; Xia, Minxuan; Yuan, Rui; Deng, Fenni; Shen, Fafu

    2016-01-01

    Soil salinity is a major environmental stress limiting plant growth and productivity. We have reported previously the isolation of an Apocynum venetum DEAD-box helicase 1 (AvDH1) that is expressed in response to salt exposure. Here, we report that the overexpression of AvDH1 driven by a constitutive cauliflower mosaic virus-35S promoter in cotton plants confers salinity tolerance. Southern and Northern blotting analyses showed that the AvDH1 gene was integrated into the cotton genome and expressed. In this study, the growth of transgenic cotton expressing AvDH1 was evaluated under saline conditions in a growth chamber and in a saline field trial. Transgenic cotton overexpressing AvDH1 was much more resistant to salt than the wild-type plants when grown in a growth chamber. The lower membrane ion leakage, along with increased activity of superoxide dismutase, in AvDH1 transgenic lines suggested that these characteristics may prevent membrane damage, which increases plant survival rates. In a saline field, the transgenic cotton lines expressing AvDH1 showed increased boll numbers, boll weights and seed cotton yields compared with wild-type plants, especially at high soil salinity levels. This study indicates that transgenic cotton expressing AvDH1 is a promising option for increasing crop productivity in saline fields. PMID:26779246

  8. Conference Planning.

    ERIC Educational Resources Information Center

    Burke, W. Warner, Ed.; Beckhard, Richard, Ed.

    This book, written to instruct in the use of a conference as a medium of social intercourse, is divided into four sections. Section I, which contains five articles, deals with factors to be considered in planning a conference. Specific techniques one can employ to improve a conference and several different techniques for evaluating the…

  9. The ULb′ Region of the Human Cytomegalovirus Genome Confers an Increased Requirement for the Viral Protein Kinase UL97

    PubMed Central

    Wang, Depeng; Li, Gang; Schauflinger, Martin; Nguyen, Christopher C.; Hall, Ellie D.; Yurochko, Andrew D.; von Einem, Jens

    2013-01-01

    We report a requirement for the viral protein kinase UL97 in human cytomegalovirus (HCMV) replication that maps to the ULb′ region of the viral genome. A UL97-null (Δ97) mutant of strain TB40/E, which encodes a full-length ULb′ region, exhibited replication defects, particularly in production of cell-free virus, that were more severe than those seen with a Δ97 mutant of laboratory strain AD169, which harbors extensive deletions in its ULb′ region. These differences were recapitulated with additional HCMV strains by treatment with a UL97 kinase inhibitor, 1-(β-l-ribofuranosyl)-2-isopropylamino-5,6-dichlorobenzimidazole (maribavir). We observed lower levels of viral DNA synthesis and an increased requirement for UL97 in viral late gene expression in strains with full-length ULb′ regions. Analysis of UL97-deficient TB40/E infections by electron microscopy revealed fewer C-capsids in nuclei, unusual viral particles in the cytoplasmic assembly compartment, and defective viral nuclear egress. Partial inhibition of viral DNA synthesis caused defects in production of cell-free virus that were up to ∼100-fold greater than those seen with cell-associated virus in strains TB40/E and TR, suggesting that UL97-dependent defects in cell-free virus production in strains with full-length ULb′ regions were secondary to DNA synthesis defects. Accordingly, a chimeric virus in which the ULb′ region of TB40/E was replaced with that of AD169 showed reduced effects of UL97 inhibition on viral DNA synthesis, late gene expression, and production of cell-free virus compared to parental TB40/E. Together, these results argue that the ULb′ region encodes a factor(s) which invokes an increased requirement for UL97 during viral DNA synthesis. PMID:23536674

  10. Bacillus licheniformis SA03 Confers Increased Saline-Alkaline Tolerance in Chrysanthemum Plants by Induction of Abscisic Acid Accumulation.

    PubMed

    Zhou, Cheng; Zhu, Lin; Xie, Yue; Li, Feiyue; Xiao, Xin; Ma, Zhongyou; Wang, Jianfei

    2017-01-01

    Soil saline-alkalization is a major abiotic stress that leads to low iron (Fe) availability and high toxicity of sodium ions (Na(+)) for plants. It has recently been shown that plant growth promoting rhizobacteria (PGPR) can enhance the ability of plants to tolerate multiple abiotic stresses such as drought, salinity, and nutrient deficiency. However, the possible involvement of PGPR in improving saline-alkaline tolerance of plants and the underlying mechanisms remain largely unknown. In this study, we investigated the effects of Bacillus licheniformis (strain SA03) on the growth of Chrysanthemum plants under saline-alkaline conditions. Our results revealed that inoculation with SA03 alleviated saline-alkaline stress in plants with increased survival rates, photosynthesis and biomass. The inoculated plants accumulated more Fe and lower Na(+) concentrations under saline-alkaline stress compared with the non-inoculated plants. RNA-Sequencing analyses further revealed that SA03 significantly activated abiotic stress- and Fe acquisition-related pathways in the stress-treated plants. However, SA03 failed to increase saline-alkaline tolerance in plants when cellular abscisic acid (ABA) and nitric oxide (NO) synthesis were inhibited by treatment with fluridone (FLU) and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO), respectively. Importantly, we also found that NO acted downstream of SA03-induced ABA to activate a series of adaptive responses in host plants under saline-alkaline stress. These findings demonstrated the potential roles of B. licheniformis SA03 in enhancing saline-alkaline tolerance of plants and highlighted the intricate integration of microbial signaling in regulating cellular Fe and Na(+) accumulation.

  11. Bacillus licheniformis SA03 Confers Increased Saline–Alkaline Tolerance in Chrysanthemum Plants by Induction of Abscisic Acid Accumulation

    PubMed Central

    Zhou, Cheng; Zhu, Lin; Xie, Yue; Li, Feiyue; Xiao, Xin; Ma, Zhongyou; Wang, Jianfei

    2017-01-01

    Soil saline-alkalization is a major abiotic stress that leads to low iron (Fe) availability and high toxicity of sodium ions (Na+) for plants. It has recently been shown that plant growth promoting rhizobacteria (PGPR) can enhance the ability of plants to tolerate multiple abiotic stresses such as drought, salinity, and nutrient deficiency. However, the possible involvement of PGPR in improving saline–alkaline tolerance of plants and the underlying mechanisms remain largely unknown. In this study, we investigated the effects of Bacillus licheniformis (strain SA03) on the growth of Chrysanthemum plants under saline–alkaline conditions. Our results revealed that inoculation with SA03 alleviated saline–alkaline stress in plants with increased survival rates, photosynthesis and biomass. The inoculated plants accumulated more Fe and lower Na+ concentrations under saline–alkaline stress compared with the non-inoculated plants. RNA-Sequencing analyses further revealed that SA03 significantly activated abiotic stress- and Fe acquisition-related pathways in the stress-treated plants. However, SA03 failed to increase saline–alkaline tolerance in plants when cellular abscisic acid (ABA) and nitric oxide (NO) synthesis were inhibited by treatment with fluridone (FLU) and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO), respectively. Importantly, we also found that NO acted downstream of SA03-induced ABA to activate a series of adaptive responses in host plants under saline–alkaline stress. These findings demonstrated the potential roles of B. licheniformis SA03 in enhancing saline–alkaline tolerance of plants and highlighted the intricate integration of microbial signaling in regulating cellular Fe and Na+ accumulation. PMID:28706529

  12. Life span extension and neuronal cell protection by Drosophila nicotinamidase.

    PubMed

    Balan, Vitaly; Miller, Gregory S; Kaplun, Ludmila; Balan, Karina; Chong, Zhao-Zhong; Li, Faqi; Kaplun, Alexander; VanBerkum, Mark F A; Arking, Robert; Freeman, D Carl; Maiese, Kenneth; Tzivion, Guri

    2008-10-10

    The life span of model organisms can be modulated by environmental conditions that influence cellular metabolism, oxidation, or DNA integrity. The yeast nicotinamidase gene pnc1 was identified as a key transcriptional target and mediator of calorie restriction and stress-induced life span extension. PNC1 is thought to exert its effect on yeast life span by modulating cellular nicotinamide and NAD levels, resulting in increased activity of Sir2 family class III histone deacetylases. In Caenorhabditis elegans, knockdown of a pnc1 homolog was shown recently to shorten the worm life span, whereas its overexpression increased survival under conditions of oxidative stress. The function and regulation of nicotinamidases in higher organisms has not been determined. Here, we report the identification and biochemical characterization of the Drosophila nicotinamidase, D-NAAM, and demonstrate that its overexpression significantly increases median and maximal fly life span. The life span extension was reversed in Sir2 mutant flies, suggesting Sir2 dependence. Testing for physiological effectors of D-NAAM in Drosophila S2 cells, we identified oxidative stress as a primary regulator, both at the transcription level and protein activity. In contrast to the yeast model, stress factors such as high osmolarity and heat shock, calorie restriction, or inhibitors of TOR and phosphatidylinositol 3-kinase pathways do not appear to regulate D-NAAM in S2 cells. Interestingly, the expression of D-NAAM in human neuronal cells conferred protection from oxidative stress-induced cell death in a sirtuin-dependent manner. Together, our findings establish a life span extending the ability of nicotinamidase in flies and offer a role for nicotinamide-modulating genes in oxidative stress regulated pathways influencing longevity and neuronal cell survival.

  13. Overexpression of the PP2A-C5 gene confers increased salt tolerance in Arabidopsis thaliana

    PubMed Central

    Hu, Rongbin; Zhu, Yinfeng; Shen, Guoxin; Zhang, Hong

    2017-01-01

    ABSTRACT Protein phosphatase 2A (PP2A) was shown to play important roles in biotic and abiotic stress signaling pathways in plants. PP2A is made of 3 subunits: a scaffolding subunit A, a regulatory subunit B, and a catalytic subunit C. It is believed that the B subunit recognizes specific substrates and the C subunit directly acts on the selected substrates, whereas the A subunit brings a B subunit and a C subunit together to form a specific PP2A holoenzyme. Because there are multiple isoforms for each PP2A subunit, there could be hundreds of novel PP2A holoenzymes in plants. For an example, there are 3 A subunits, 17 B subunits, and 5 C subunits in Arabidopsis, which could form 255 different PP2A holoenzymes. Understanding the roles of these PP2A holoenzymes in various signaling pathways is a challenging task. In a recent study,1 we discovered that PP2A-C5, the catalytic subunit 5 of PP2A, plays an important role in salt tolerance in Arabidopsis. We found that a knockout mutant of PP2A-C5 (i.e. pp2a-c5–1) was very sensitive to salt treatments, whereas PP2A-C5-overexpressing plants were more tolerant to salt stresses. Genetic analyses between pp2a-c5–1 and Salt-Overly-Sensitive (SOS) mutants indicated that PP2A-C5 does not function in the same pathway as SOS genes. Using yeast 2-hybrid analysis, we found that PP2A-C5 interacts with several vacuolar membrane bound chloride channel proteins. We hypothesize that these vacuolar chloride channel proteins might be PP2A-C5's substrates in vivo, and the action of PP2A-C5 on these channel proteins could increase or activate their activities, thereby result in accumulation of the chloride and sodium contents in vacuoles, leading to increased salt tolerance in plants. PMID:28045581

  14. Increasing Understanding of Public Problems and Policies, 1994. [National Public Policy Education Conference (44th, Boise, Idaho, September 18-21, 1994).

    ERIC Educational Resources Information Center

    Halbrook, Steve A., Ed.; Grace, Teddee E., Ed.

    The National Public Policy Education Conference is held annually to improve the policy education efforts of extension workers responsible for public affairs programs. The 1994 conference addressed the following topics: (1) ethical perspectives in public policy education; (2) transition of food and agricultural policy; (3) building human…

  15. Sleep and wakefulness in Drosophila melanogaster

    PubMed Central

    Cirelli, Chiara; Bushey, Daniel

    2009-01-01

    Summary Sleep is present and tightly regulated in every vertebrate species in which it has been carefully investigated, but what sleep is for remains a mystery. Sleep is also present in invertebrates, and an extensive analysis in Drosophila melanogaster has shown that sleep in fruit flies show most of the fundamental features that characterize sleep in mammals. In Drosophila, fly sleep consists of sustained periods of quiescence associated with an increased arousal threshold. Fly sleep is modulated by several of the same stimulants and hypnotics that affect mammalian sleep. Moreover, like in mammals, fly sleep shows remarkable interindividual variability. The expression of several genes involved in energy metabolism, synaptic plasticity, and the response to cellular stress varies in Drosophila between sleep and wakefulness, and the same occurs in rodents. Brain activity also changes in flies as a function of behavioral state. Furthermore, Drosophila sleep is tightly regulated in a circadian and homeostatic manner, and the homeostatic regulation is largely independent of the circadian regulation. After sleep deprivation recovery sleep in flies is longer in duration and more consolidated, as indicated by an increase in arousal threshold and fewer brief awakenings. Finally, sleep deprivation in flies impairs vigilance and performance. Because of the extensive similarities between flies and mammals, Drosophila is now being used as a promising model system for the genetic dissection of sleep. Over the last few years, mutagenesis screens have isolated several short sleeping mutants, a demonstration that that single genes can have a powerful effect on a complex trait like sleep. PMID:18591491

  16. Using polarization-sensitive optical coherence tomography to identify tumor stromal fibrosis and increase tumor biopsy yield (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hariri, Lida P.; Adams, David C.; Miller, Alyssa J.; Mino-Kenudson, Mari; Suter, Melissa J.

    2016-03-01

    Tissue biopsy is the principal method used to diagnose tumors in a variety of organ systems. It is essential to maximize tumor yield in biopsy specimens for both clinical diagnostic and research purposes. This is particularly important in tumors where additional tissue is needed for molecular analysis to identify patients who would benefit from mutation-specific targeted therapy, such as in lung carcinomas. Inadvertent sampling of fibrotic stroma within tumor nodules contaminates biopsies, decreases tumor yield, and can impede diagnosis. The ability to assess tumor composition and guide biopsy site selection in real time is likely to improve diagnostic yield. Polarization sensitive OCT (PS-OCT) measures birefringence in organized tissues, such as collagen, and could be used to distinguish tumor from fibrosis. In this study, PS-OCT was obtained in 65 lung nodule samples from surgical resection specimens containing varying ratios of tumor and fibrosis. PS-OCT was obtained with either a custom-built helical scanning catheter (0.8 or 1.6mm in diameter) or a dual-axis bench top scanner. Strong birefringence was observed in nodules containing dense fibrosis, with no birefringence in adjacent regions of tumor. Tumors admixed with early, loosely-organized collagen demonstrated mild-to-moderate birefringence, and tumors with little collagen content showed little to no birefringent signal. PS-OCT provides significant insights into tumor nodule composition, and has potential to differentiate tumor from stromal fibrosis during biopsy site selection to increase diagnostic tumor yield.

  17. Cucumber metal transport protein MTP8 confers increased tolerance to manganese when expressed in yeast and Arabidopsis thaliana

    PubMed Central

    Migocka, Magdalena; Papierniak, Anna; Maciaszczyk-Dziubińska, Ewa; Poździk, Piotr; Posyniak, Ewelina; Garbiec, Arnold; Filleur, Sophie

    2014-01-01

    Cation diffusion facilitator (CDF) proteins are ubiquitous divalent cation transporters that have been proved to be essential for metal homeostasis and tolerance in Archaebacteria, Bacteria, and Eukaryota. In plants, CDFs are designated as metal tolerance proteins (MTPs). Due to the lack of genomic resources, studies on MTPs in other plants, including cultivated crops, are lacking. Here, the identification and organization of genes encoding members of the MTP family in cucumber are described. The first functional characterization of a cucumber gene encoding a member of the Mn-CDF subgroup of CDF proteins, designated as CsMTP8 based on the highest homology to plant MTP8, is also presented. The expression of CsMTP8 in Saccharomyces cerevisiae led to increased Mn accumulation in yeast cells and fully restored the growth of mutants hypersensitive to Mn in Mn excess. Similarly, the overexpression of CsMTP8 in Arabidopsis thaliana enhanced plant tolerance to high Mn in nutrition media as well as the accumulation of Mn in plant tissues. When fused to green fluorescent protein (GFP), CsMTP8 localized to the vacuolar membranes in yeast cells and to Arabidopsis protoplasts. In cucumber, CsMTP8 was expressed almost exclusively in roots, and the level of gene transcript was markedly up-regulated or reduced under elevated Mn or Mn deficiency, respectively. Taken together, the results suggest that CsMTP8 is an Mn transporter localized in the vacuolar membrane, which participates in the maintenance of Mn homeostasis in cucumber root cells. PMID:25039075

  18. Cucumber metal transport protein MTP8 confers increased tolerance to manganese when expressed in yeast and Arabidopsis thaliana.

    PubMed

    Migocka, Magdalena; Papierniak, Anna; Maciaszczyk-Dziubińska, Ewa; Poździk, Piotr; Posyniak, Ewelina; Garbiec, Arnold; Filleur, Sophie

    2014-10-01

    Cation diffusion facilitator (CDF) proteins are ubiquitous divalent cation transporters that have been proved to be essential for metal homeostasis and tolerance in Archaebacteria, Bacteria, and Eukaryota. In plants, CDFs are designated as metal tolerance proteins (MTPs). Due to the lack of genomic resources, studies on MTPs in other plants, including cultivated crops, are lacking. Here, the identification and organization of genes encoding members of the MTP family in cucumber are described. The first functional characterization of a cucumber gene encoding a member of the Mn-CDF subgroup of CDF proteins, designated as CsMTP8 based on the highest homology to plant MTP8, is also presented. The expression of CsMTP8 in Saccharomyces cerevisiae led to increased Mn accumulation in yeast cells and fully restored the growth of mutants hypersensitive to Mn in Mn excess. Similarly, the overexpression of CsMTP8 in Arabidopsis thaliana enhanced plant tolerance to high Mn in nutrition media as well as the accumulation of Mn in plant tissues. When fused to green fluorescent protein (GFP), CsMTP8 localized to the vacuolar membranes in yeast cells and to Arabidopsis protoplasts. In cucumber, CsMTP8 was expressed almost exclusively in roots, and the level of gene transcript was markedly up-regulated or reduced under elevated Mn or Mn deficiency, respectively. Taken together, the results suggest that CsMTP8 is an Mn transporter localized in the vacuolar membrane, which participates in the maintenance of Mn homeostasis in cucumber root cells. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. Overexpression of rice serotonin N-acetyltransferase 1 in transgenic rice plants confers resistance to cadmium and senescence and increases grain yield.

    PubMed

    Lee, Kyungjin; Back, Kyoungwhan

    2017-04-01

    While ectopic overexpression of serotonin N-acetyltransferase (SNAT) in plants has been accomplished using animal SNAT genes, ectopic overexpression of plant SNAT genes in plants has not been investigated. Because the plant SNAT protein differs from that of animals in its subcellular localization and enzyme kinetics, its ectopic overexpression in plants would be expected to give outcomes distinct from those observed from overexpression of animal SNAT genes in transgenic plants. Consistent with our expectations, we found that transgenic rice plants overexpressing rice (Oryza sativa) SNAT1 (OsSNAT1) did not show enhanced seedling growth like that observed in ovine SNAT-overexpressing transgenic rice plants, although both types of plants exhibited increased melatonin levels. OsSNAT1-overexpressing rice plants did show significant resistance to cadmium and senescence stresses relative to wild-type controls. In contrast to tomato, melatonin synthesis in rice seedlings was not induced by selenium and OsSNAT1 transgenic rice plants did not show tolerance to selenium. T2 homozygous OsSNAT1 transgenic rice plants exhibited increased grain yield due to increased panicle number per plant under paddy field conditions. These benefits conferred by ectopic overexpression of OsSNAT1 had not been observed in transgenic rice plants overexpressing ovine SNAT, suggesting that plant SNAT functions differently from animal SNAT in plants. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Meiosis in male Drosophila

    PubMed Central

    McKee, Bruce D.; Yan, Rihui; Tsai, Jui-He

    2012-01-01

    Meiosis entails sorting and separating both homologous and sister chromatids. The mechanisms for connecting sister chromatids and homologs during meiosis are highly conserved and include specialized forms of the cohesin complex and a tightly regulated homolog synapsis/recombination pathway designed to yield regular crossovers between homologous chromatids. Drosophila male meiosis is of special interest because it dispenses with large segments of the standard meiotic script, particularly recombination, synapsis and the associated structures. Instead, Drosophila relies on a unique protein complex composed of at least two novel proteins, SNM and MNM, to provide stable connections between homologs during meiosis I. Sister chromatid cohesion in Drosophila is mediated by cohesins, ring-shaped complexes that entrap sister chromatids. However, unlike other eukaryotes Drosophila does not rely on the highly conserved Rec8 cohesin in meiosis, but instead utilizes two novel cohesion proteins, ORD and SOLO, which interact with the SMC1/3 cohesin components in providing meiotic cohesion. PMID:23087836

  1. In focus: spotted wing drosophila, Drosophila suzukii, across perspectives

    USDA-ARS?s Scientific Manuscript database

    An effective response to the invasion of spotted wing Drosophila (SWD), Drosophila suzukii, requires proper taxonomic identification at the initial phase, understanding its basic biology and phenology, developing management tools, transferring information and technology quickly to user groups, and e...

  2. Increased body mass index but not common vitamin D receptor, peroxisome proliferator-activated receptor γ, or cytokine polymorphisms confers predisposition to posttransplant diabetes.

    PubMed

    Wang, Ping; Hudspeth, Elissa

    2011-12-01

    Posttransplant diabetes mellitus (PTDM) is a major complication after solid organ transplantation. The use of corticosteroids and calcineurin inhibitors, especially tacrolimus, are significant risk factors. However, it is not clear what genetic factors modify the risk. Evidence suggests vitamin D deficiency, perturbed glucose homeostasis, and increased inflammation all play roles in the development of diabetes. To investigate whether common vitamin D receptor (VDR), cytokine, and peroxisome proliferator-activated receptor γ (PPARγ) polymorphisms are correlated with the development of PTDM. DNA was isolated from the peripheral blood of 51 kidney transplant recipients with PTDM and 72 patients without diabetes pretransplant or posttransplant at the time of follow-up. The genotypes for 5 polymorphisms, 1 each in VDR, PPARγ, INFγ, TGFβ1, and TNF, were determined using direct sequencing. Age, sex, number of acute rejection episodes, follow-up length, ethnicity, body mass index, and the frequency of alleles and genotypes for each polymorphism were compared between the 2 groups. Body mass index was the only factor that was statistically different between the 2 groups (P  =  .001). The frequency of different alleles and genotypes for each of the 5 polymorphisms did not differ between the 2 groups. These results indicate that increased body mass index is a significant risk factor for the development of PTDM. However, none of the genetic polymorphisms studied confer predisposition to PTDM with the current sample size.

  3. MDM2 SNP309 does not confer an increased risk to oral squamous cell carcinoma but may modulate the age of disease onset.

    PubMed

    Hamid, Sharifah; Yang, Yi-Hsin; Peng, Karen Ng Lee; Ismail, Siti Mazlipah; Zain, Rosnah Binti; Lim, Kue Peng; Wan Mustafa, Wan Mahadzir; Abraham, Mannil Thomas; Teo, Soo-Hwang; Cheong, Sok Ching

    2009-06-01

    The MDM2 SNP309 has been associated with increased expression of the protein which could suppress p53 function, and has been shown to modulate risk to cancer. We have previously shown that overexpression of MDM2 is a common event in oral cancers. In the present study, we determined the association between the MDM2 SNP309 polymorphism and oral cancer in 207 oral cancer patients and 116 normal subjects. We genotyped the MDM2 SNP309 by PCR-RFLP. Logistic regression was adapted to calculate odds ratios for MDM2 SNP309 polymorphism from univariate and multivariable adjusted models. Our results suggest that MDM2 SNP309 does not confer increased risk to oral cancer (OR=1.55, 95% CI=0.77-3.11). However, the GG/TG genotype was associated with later disease onset in women above 55 years of age. Collectively, our data suggests that MDM2 SNP309 may modulate the risk to oral cancer and is a modifier of the age at oral cancer onset in women above the age of 55 years.

  4. Measuring Drosophila (fruit fly) activity during microgravity exposure.

    PubMed

    Miller, M S; Keller, T S

    1999-07-01

    Important advances in the understanding of the aging process could be obtained through comprehension of the changes experienced by Drosophila melanogaster (fruit flies) during microgravity. Previous experiments flown on Cosmos satellites and various Space Shuttle missions have shown a significant decrease in the life span of young male Drosophila after microgravity exposure. Additionally, postflight analysis indicated an accelerated aging of the microgravity exposed male flies since they exhibited a significant decrease in mating ability and a consistently lower negative geotaxis response than the 1 g ground controls. The negative geotaxis response is the Drosophila's reaction to move opposite to the Earth's gravitational vector when disturbed in certain manners. Researchers have hypothesized that the accelerated aging, is due to an increased locomotor activity which causes a subsequent increase in mitochondrial activity. The increased mitochondrial activity, in turn, causes increased aging through accelerated damage to the mitochondrial system. An increase in locomotor activity was indicated by analyzing only a fraction (1/6th of a second) of the 15 minute video recordings of groups of Drosophila taken approximately every two days during a 14-day Space Shuttle flight. The increased locomotor activity may be related to the Drosophila's negative geotaxis response in that the flies may be reacting to the absence of normal gravity by continuously searching for the gravity vector. The aims of this study are to develop methods to accurately measure individual Drosophila activity, use these derived methods in 1 g to create a Drosophila activity baseline, and use the methods during short and long duration microgravity exposure (sounding rockets, parabolic flights, Space Shuttle, International Space Station, etc.) to examine Drosophila activity. The role of the negative geotaxis response on locomotor activity will be examined by using two strains of behaviorally selected

  5. Arabidopsis actin capping protein (AtCP) subunits have different expression patterns, and downregulation of AtCPB confers increased thermotolerance of Arabidopsis after heat shock stress.

    PubMed

    Wang, Jue; Qian, Dong; Fan, Tingting; Jia, Honglei; An, Lizhe; Xiang, Yun

    2012-09-01

    As a heterodimer actin-binding protein, capping protein is composed of α and β subunits, and can stabilize the actin filament cytoskeleton by binding to F-actin ends to inhibit G-actin addition or loss from that end. Until now, studies on plant capping protein have focused on biochemical functions in vitro, and so the expression patterns and physiological functions of actin capping protein in Arabidopsis (AtCP) are poorly understood. In the present study, real-time quantitative PCR and Western blot analysis showed that although AtCP α and β subunits (i.e. AtCPA and AtCPB) were expressed in various tissues, their expression patterns were significantly different. GUS staining further indicated they were present in different parts of the same organs. We also demonstrated that the expression levels of both subunits were induced by heat shock stress. However, only the atcpβ-mutant showed enhanced thermotolerance, and confocal microscopy showed that the actin filaments of the atcpβ-mutant were much more complete than that in the wild-type and the atcpα-mutant after heat treatment at 45 °C for 40 and 45 min. In conclusion, these results demonstrated that AtCPA and AtCPB showed distinct expression patterns in vivo, and that downregulation of AtCPB conferred increased plant thermotolerance after heat shock stress.

  6. New insights into Drosophila vision.

    PubMed

    Dolph, Patrick

    2008-01-10

    Studies of the Drosophila visual system have provided valuable insights into the function and regulation of phototransduction signaling pathways. Much of this work has stemmed from or relied upon the genetic tools offered by the Drosophila system. In this issue of Neuron, Wang and colleagues and Acharya and colleagues have further exploited the Drosophila genetic system to characterize two new phototransduction players.

  7. The variant allele of the rs188140481 polymorphism confers a moderate increase in the risk of prostate cancer in Polish men.

    PubMed

    Antczak, Andrzej; Wokołorczyk, Dominika; Kluźniak, Wojciech; Kashyap, Aniruddh; Jakubowska, Anna; Gronwald, Jacek; Huzarski, Tomasz; Byrski, Tomasz; Dębniak, Tadeusz; Masojć, Bartłomiej; Górski, Bohdan; Gromowski, Tomasz; Gołąb, Adam; Sikorski, Andrzej; Słojewski, Marcin; Gliniewicz, Bartłomiej; Borkowski, Tomasz; Borkowski, Andrzej; Przybyła, Jacek; Sosnowski, Marek; Małkiewicz, Bartosz; Zdrojowy, Romuald; Sikorska-Radek, Paulina; Matych, Józef; Wilkosz, Jacek; Różański, Waldemar; Kiś, Jacek; Bar, Krzysztof; Janiszewska, Hanna; Stawicka, Małgorzata; Milecki, Piotr; Lubiński, Jan; Narod, Steven A; Cybulski, Cezary

    2015-03-01

    A number of single nucleotide polymorphisms (SNPs) in the human genome have been associated with increased risk of prostate cancer. Recently, a single SNP in the region of chromosome 8q24 (rs188140481) has been associated with a three-fold increased risk of prostate cancer in Europe and North America. To establish whether rs188140481 is associated with the risk of prostate cancer in Poland, we genotyped 3467 men with prostate cancer and 1958 controls. The A allele of rs188140481 was detected in 44 of 3467 (1.3%) men with prostate cancer and in seven of 1958 (0.4%) controls (odds ratio=3.6; 95% confidence interval 1.6-7.9; P=0.0006). The allele was present in eight of 390 (2.1%) men with familial prostate cancer (odds ratio=5.8; 95% confidence interval 2.1-16.2; P=0.001). A positive family history of cancers at sites other than the prostate was observed in 27% of men who carried the rs188140481 risk allele and in 44% of noncarriers (P=0.04). No cancer at a site other than the prostate was more common in first-degree or second-degree relatives of carriers of the rs188140481 risk allele than relatives of noncarriers. The rs188140481 polymorphism in the 8q24 region confers a moderate increase in the risk of prostate cancer in Polish men. The SNP does not appear to be associated with susceptibility to cancers of other types.

  8. Infection Dynamics and Immune Response in a Newly Described Drosophila-Trypanosomatid Association

    PubMed Central

    Votýpka, Jan; Dostálová, Anna; Yurchenko, Vyacheslav; Bird, Nathan H.; Lukeš, Julius; Lemaitre, Bruno

    2015-01-01

    ABSTRACT Trypanosomatid parasites are significant causes of human disease and are ubiquitous in insects. Despite the importance of Drosophila melanogaster as a model of infection and immunity and a long awareness that trypanosomatid infection is common in the genus, no trypanosomatid parasites naturally infecting Drosophila have been characterized. Here, we establish a new model of trypanosomatid infection in Drosophila—Jaenimonas drosophilae, gen. et sp. nov. As far as we are aware, this is the first Drosophila-parasitic trypanosomatid to be cultured and characterized. Through experimental infections, we find that Drosophila falleni, the natural host, is highly susceptible to infection, leading to a substantial decrease in host fecundity. J. drosophilae has a broad host range, readily infecting a number of Drosophila species, including D. melanogaster, with oral infection of D. melanogaster larvae resulting in the induction of numerous immune genes. When injected into adult hemolymph, J. drosophilae kills D. melanogaster, although interestingly, neither the Imd nor the Toll pathway is induced and Imd mutants do not show increased susceptibility to infection. In contrast, mutants deficient in drosocrystallin, a major component of the peritrophic matrix, are more severely infected during oral infection, suggesting that the peritrophic matrix plays an important role in mediating trypanosomatid infection in Drosophila. This work demonstrates that the J. drosophilae-Drosophila system can be a powerful model to uncover the effects of trypanosomatids in their insect hosts. PMID:26374124

  9. Geotaxis baseline data for Drosophila

    NASA Technical Reports Server (NTRS)

    Schnebel, E. M.; Bhargava, R.; Grossfield, J.

    1987-01-01

    Geotaxis profiles for 20 Drosophila species and semispecies at different ages have been examined using a calibrated, adjustable slant board device. Measurements were taken at 5 deg intervals ranging from 0 deg to 85 deg. Clear strain and species differences are observed, with some groups tending to move upward (- geotaxis) with increasing angles, while others move downward (+ geotaxis). Geotactic responses change with age in some, but not all experimental groups. Sample geotaxis profiles are presented and their application to ecological and aging studies are discussed. Data provide a baseline for future evaluations of the biological effects of microgravity.

  10. Reduced spray programs for Drosophila suzukii management in berry crops

    USDA-ARS?s Scientific Manuscript database

    BACKGROUND: Since the arrival of Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), field applications of broad-spectrum insecticides have significantly increased to protect susceptible fruit from infestation in berry crop production. Field studies were conducted from 2011 to 2013 to determine...

  11. Obesogenic memory can confer long-term increases in adipose tissue but not liver inflammation and insulin resistance after weight loss.

    PubMed

    Schmitz, J; Evers, N; Awazawa, M; Nicholls, H T; Brönneke, H S; Dietrich, A; Mauer, J; Blüher, M; Brüning, J C

    2016-05-01

    Obesity represents a major risk factor for the development of type 2 diabetes mellitus, atherosclerosis and certain cancer entities. Treatment of obesity is hindered by the long-term maintenance of initially reduced body weight, and it remains unclear whether all pathologies associated with obesity are fully reversible even upon successfully maintained weight loss. We compared high fat diet-fed, weight reduced and lean mice in terms of body weight development, adipose tissue and liver insulin sensitivity as well as inflammatory gene expression. Moreover, we assessed similar parameters in a human cohort before and after bariatric surgery. Compared to lean animals, mice that demonstrated successful weight reduction showed increased weight gain following exposure to ad libitum control diet. However, pair-feeding weight-reduced mice with lean controls efficiently stabilized body weight, indicating that hyperphagia was the predominant cause for the observed weight regain. Additionally, whereas glucose tolerance improved rapidly after weight loss, systemic insulin resistance was retained and ameliorated only upon prolonged pair-feeding. Weight loss enhanced insulin action and resolved pro-inflammatory gene expression exclusively in the liver, whereas visceral adipose tissue displayed no significant improvement of metabolic and inflammatory parameters compared to obese mice. Similarly, bariatric surgery in humans (n = 55) resulted in massive weight reduction, improved hepatic inflammation and systemic glucose homeostasis, while adipose tissue inflammation remained unaffected and adipocyte-autonomous insulin action only exhibit minor improvements in a subgroup of patients (42%). These results demonstrate that although sustained weight loss improves systemic glucose homeostasis, primarily through improved inflammation and insulin action in liver, a remarkable obesogenic memory can confer long-term increases in adipose tissue inflammation and insulin resistance in mice as

  12. D-Alanylation of Lipoteichoic Acids Confers Resistance to Cationic Peptides in Group B Streptococcus by Increasing the Cell Wall Density

    PubMed Central

    Saar-Dover, Ron; Bitler, Arkadi; Nezer, Ravit; Shmuel-Galia, Liraz; Firon, Arnaud; Shimoni, Eyal; Trieu-Cuot, Patrick; Shai, Yechiel

    2012-01-01

    Cationic antimicrobial peptides (CAMPs) serve as the first line of defense of the innate immune system against invading microbial pathogens. Gram-positive bacteria can resist CAMPs by modifying their anionic teichoic acids (TAs) with D-alanine, but the exact mechanism of resistance is not fully understood. Here, we utilized various functional and biophysical approaches to investigate the interactions of the human pathogen Group B Streptococcus (GBS) with a series of CAMPs having different properties. The data reveal that: (i) D-alanylation of lipoteichoic acids (LTAs) enhance GBS resistance only to a subset of CAMPs and there is a direct correlation between resistance and CAMPs length and charge density; (ii) resistance due to reduced anionic charge of LTAs is not attributed to decreased amounts of bound peptides to the bacteria; and (iii) D-alanylation most probably alters the conformation of LTAs which results in increasing the cell wall density, as seen by Transmission Electron Microscopy, and reduces the penetration of CAMPs through the cell wall. Furthermore, Atomic Force Microscopy reveals increased surface rigidity of the cell wall of the wild-type GBS strain to more than 20-fold that of the dltA mutant. We propose that D-alanylation of LTAs confers protection against linear CAMPs mainly by decreasing the flexibility and permeability of the cell wall, rather than by reducing the electrostatic interactions of the peptide with the cell surface. Overall, our findings uncover an important protective role of the cell wall against CAMPs and extend our understanding of mechanisms of bacterial resistance. PMID:22969424

  13. miR-335 Targets SIAH2 and Confers Sensitivity to Anti-Cancer Drugs by Increasing the Expression of HDAC3

    PubMed Central

    Kim, Youngmi; Kim, Hyuna; Park, Deokbum; Jeoung, Dooil

    2015-01-01

    We previously reported the role of histone deacetylase 3 (HDAC3) in response to anti-cancer drugs. The decreased expression of HDAC3 in anti-cancer drug-resistant cancer cell line is responsible for the resistance to anti-cancer drugs. In this study, we investigated molecular mechanisms associated with regulation of HDAC3 expression. MG132, an inhibitor of proteasomal degradation, induced the expression of HDAC3 in various anti-cancer drug-resistant cancer cell lines. Ubiquitination of HDAC3 was observed in various anti-cancer drug-resistant cancer cell lines. HDAC3 showed an interaction with SIAH2, an ubiquitin E3 ligase, that has increased expression in various anti-cancer drug-resistant cancer cell lines. miRNA array analysis showed the decreased expression of miR-335 in these cells. Targetscan analysis predicted the binding of miR-335 to the 3′-UTR of SIAH2. miR-335-mediated increased sensitivity to anti-cancer drugs was associated with its effect on HDAC3 and SIAH2 expression. miR-335 exerted apoptotic effects and inhibited ubiquitination of HDAC3 in anti-cancer drug-resistant cancer cell lines. miR-335 negatively regulated the invasion, migration, and growth rate of cancer cells. The mouse xenograft model showed that miR-335 negatively regulated the tumorigenic potential of cancer cells. The down-regulation of SIAH2 conferred sensitivity to anti-cancer drugs. The results of the study indicated that the miR-335/SIAH2/HDAC3 axis regulates the response to anti-cancer drugs. PMID:25997740

  14. Obesogenic memory can confer long-term increases in adipose tissue but not liver inflammation and insulin resistance after weight loss

    PubMed Central

    Schmitz, J.; Evers, N.; Awazawa, M.; Nicholls, H.T.; Brönneke, H.S.; Dietrich, A.; Mauer, J.; Blüher, M.; Brüning, J.C.

    2016-01-01

    Objective Obesity represents a major risk factor for the development of type 2 diabetes mellitus, atherosclerosis and certain cancer entities. Treatment of obesity is hindered by the long-term maintenance of initially reduced body weight, and it remains unclear whether all pathologies associated with obesity are fully reversible even upon successfully maintained weight loss. Methods We compared high fat diet-fed, weight reduced and lean mice in terms of body weight development, adipose tissue and liver insulin sensitivity as well as inflammatory gene expression. Moreover, we assessed similar parameters in a human cohort before and after bariatric surgery. Results Compared to lean animals, mice that demonstrated successful weight reduction showed increased weight gain following exposure to ad libitum control diet. However, pair-feeding weight-reduced mice with lean controls efficiently stabilized body weight, indicating that hyperphagia was the predominant cause for the observed weight regain. Additionally, whereas glucose tolerance improved rapidly after weight loss, systemic insulin resistance was retained and ameliorated only upon prolonged pair-feeding. Weight loss enhanced insulin action and resolved pro-inflammatory gene expression exclusively in the liver, whereas visceral adipose tissue displayed no significant improvement of metabolic and inflammatory parameters compared to obese mice. Similarly, bariatric surgery in humans (n = 55) resulted in massive weight reduction, improved hepatic inflammation and systemic glucose homeostasis, while adipose tissue inflammation remained unaffected and adipocyte-autonomous insulin action only exhibit minor improvements in a subgroup of patients (42%). Conclusions These results demonstrate that although sustained weight loss improves systemic glucose homeostasis, primarily through improved inflammation and insulin action in liver, a remarkable obesogenic memory can confer long-term increases in adipose tissue

  15. Hearing regulates Drosophila aggression

    PubMed Central

    Versteven, Marijke; Vanden Broeck, Lies; Geurten, Bart; Zwarts, Liesbeth; Decraecker, Lisse; Beelen, Melissa; Göpfert, Martin C.; Heinrich, Ralf; Callaerts, Patrick

    2017-01-01

    Aggression is a universal social behavior important for the acquisition of food, mates, territory, and social status. Aggression in Drosophila is context-dependent and can thus be expected to involve inputs from multiple sensory modalities. Here, we use mechanical disruption and genetic approaches in Drosophila melanogaster to identify hearing as an important sensory modality in the context of intermale aggressive behavior. We demonstrate that neuronal silencing and targeted knockdown of hearing genes in the fly’s auditory organ elicit abnormal aggression. Further, we show that exposure to courtship or aggression song has opposite effects on aggression. Our data define the importance of hearing in the control of Drosophila intermale aggression and open perspectives to decipher how hearing and other sensory modalities are integrated at the neural circuit level. PMID:28115690

  16. Sterile Inflammation in Drosophila

    PubMed Central

    Shaukat, Zeeshan; Liu, Dawei; Gregory, Stephen

    2015-01-01

    The study of immune responses in Drosophila has already yielded significant results with impacts on our understanding of vertebrate immunity, such as the characterization of the Toll receptor. Several recent papers have focused on the humoral response to damage signals rather than pathogens, particularly damage signals from tumour-like tissues generated by loss of cell polarity or chromosomal instability. Both the triggers that generate this sterile inflammation and the systemic and local effects of it are only just beginning to be characterized in Drosophila. Here we review the molecular mechanisms that are known that give rise to the recruitment of Drosophila phagocytes, called hemocytes, as well as the signals, such as TNFα, that stimulated hemocytes emit at sites of perceived damage. The signalling consequences of inflammation, such as the activation of JNK, and the potential for modifying this response are also discussed. PMID:25948885

  17. Hearing regulates Drosophila aggression.

    PubMed

    Versteven, Marijke; Vanden Broeck, Lies; Geurten, Bart; Zwarts, Liesbeth; Decraecker, Lisse; Beelen, Melissa; Göpfert, Martin C; Heinrich, Ralf; Callaerts, Patrick

    2017-02-21

    Aggression is a universal social behavior important for the acquisition of food, mates, territory, and social status. Aggression in Drosophila is context-dependent and can thus be expected to involve inputs from multiple sensory modalities. Here, we use mechanical disruption and genetic approaches in Drosophila melanogaster to identify hearing as an important sensory modality in the context of intermale aggressive behavior. We demonstrate that neuronal silencing and targeted knockdown of hearing genes in the fly's auditory organ elicit abnormal aggression. Further, we show that exposure to courtship or aggression song has opposite effects on aggression. Our data define the importance of hearing in the control of Drosophila intermale aggression and open perspectives to decipher how hearing and other sensory modalities are integrated at the neural circuit level.

  18. In Focus: Spotted wing drosophila, Drosophila suzukii, across perspectives.

    PubMed

    Lee, Jana C; Bruck, Denny J; Dreves, Amy J; Ioriatti, Claudio; Vogt, Heidrun; Baufeld, Peter

    2011-11-01

    In August 2008, the first detection of the spotted wing drosophila, Drosophila suzukii, to the North America mainland in California caused great concern, as the fly was found infesting a variety of commercial fruits. Subsequent detections followed in Oregon, Washington, Florida and British Columbia in 2009; in Utah, North Carolina, South Carolina, Michigan, and Louisiana in 2010; and in Virginia, Montana, Wisconsin, Pennsylvania, New Jersey, Maryland and Mexico in 2011. In Europe, it has been detected in Italy and Spain in 2009 and in France in 2010. Economic costs to the grower from D. suzukii include the increased cost of production (increased labor and materials for chemical inputs, monitoring and other management tools) and crop loss. An effective response to the invasion of D. suzukii requires proper taxonomic identification at the initial phase, understanding basic biology and phenology, developing management tools, transferring information and technology quickly to user groups, and evaluating the impact of the research and extension program on an economic, social, and environmental level. As D. suzukii continues to expand its range, steps must be initiated in each new region to educate and inform the public as well as formulate management tactics suitable for the crops and growing conditions in each. Copyright © 2011 Society of Chemical Industry.

  19. 1985 oil spill conference

    SciTech Connect

    Not Available

    1985-02-01

    This 1985 Oil Spill Conference, our ninth biennial meeting, presents another unique opportunity fo industry, government, and academic representatives to meet and exchange ideas to enhance our knowledge and understanding of the prevention, behavior, control, and cleanup of oil spills. Growing international and domestic participation, and the continued worldwide use of the Proceedings of past oil spill conferences as valuable reference sources affirms the importance and quality of these conferences. It is my firm belief, furthermore, that the conferences have contributed substantially to the reduction in the number of marine oil spills, and to our increased cleanup capabilities. The sponsoring organizations--the United States Coast Guard, the American Petroleum Institute, and the United States Environmental Protection Agency--have combined their efforts to provide a program of timely technical content which affords the opportunity to review the state-of-the-art accomplishments since our last conference in 1983. Finally, I hope that the knowledge and associations developed at this conference will influence your decision to participate in the 1987 Oil Spill Conference, to be held in Baltimore, Maryland.

  20. Studying aging in Drosophila.

    PubMed

    He, Ying; Jasper, Heinrich

    2014-06-15

    Drosophila melanogaster represents one of the most important genetically accessible model organisms for aging research. Studies in flies have identified single gene mutations that influence lifespan and have characterized endocrine signaling interactions that control homeostasis systemically. Recent studies have focused on the effects of aging on specific tissues and physiological processes, providing a comprehensive picture of age-related tissue dysfunction and the loss of systemic homeostasis. Here we review methodological aspects of this work and highlight technical considerations when using Drosophila to study aging and age-related diseases.

  1. Chemical sensing in Drosophila.

    PubMed

    Benton, Richard

    2008-08-01

    Chemical sensing begins when peripheral receptor proteins recognise specific environmental stimuli and translate them into spatial and temporal patterns of sensory neuron activity. The chemosensory system of the fruit fly, Drosophila melanogaster, has become a dominant model to understand this process, through its accessibility to a powerful combination of molecular, genetic and electrophysiological analysis. Recent results have revealed many surprises in the biology of peripheral chemosensation in Drosophila, including novel structural and signalling properties of the insect odorant receptors (ORs), combinatorial mechanisms of chemical recognition by the gustatory receptors (GRs), and the implication of Transient Receptor Potential (TRP) ion channels as a novel class of chemosensory receptors.

  2. A Drosophila model to investigate the neurotoxic side effects of radiation exposure

    PubMed Central

    Sudmeier, Lisa J.; Howard, Steven P.; Ganetzky, Barry

    2015-01-01

    ABSTRACT Children undergoing cranial radiation therapy (CRT) for pediatric central nervous system malignancies are at increased risk for neurological deficits later in life. We have developed a model of neurotoxic damage in adult Drosophila following irradiation during the juvenile stages with the goal of elucidating underlying neuropathological mechanisms and of ultimately identifying potential therapeutic targets. Wild-type third-instar larvae were irradiated with single doses of γ-radiation, and the percentage that survived to adulthood was determined. Motor function of surviving adults was examined with a climbing assay, and longevity was assessed by measuring lifespan. Neuronal cell death was assayed by using immunohistochemistry in adult brains. We also tested the sensitivity at different developmental stages by irradiating larvae at various time points. Irradiating late third-instar larvae at a dose of 20 Gy or higher impaired the motor activity of surviving adults. A dose of 40 Gy or higher resulted in a precipitous reduction in the percentage of larvae that survive to adulthood. A dose-dependent decrease in adult longevity was paralleled by a dose-dependent increase in activated Death caspase-1 (Dcp1) in adult brains. Survival to adulthood and adult lifespan were more severely impaired with decreasing larval age at the time of irradiation. Our initial survey of the Drosophila Genetic Reference Panel demonstrated that differences in genotype can confer phenotypic differences in radio-sensitivity for developmental survival and motor function. This work demonstrates the usefulness of Drosophila to model the toxic effects of radiation during development, and has the potential to unravel underlying mechanisms and to facilitate the discovery of novel therapeutic interventions. PMID:26092528

  3. A Drosophila model to investigate the neurotoxic side effects of radiation exposure.

    PubMed

    Sudmeier, Lisa J; Howard, Steven P; Ganetzky, Barry

    2015-07-01

    Children undergoing cranial radiation therapy (CRT) for pediatric central nervous system malignancies are at increased risk for neurological deficits later in life. We have developed a model of neurotoxic damage in adult Drosophila following irradiation during the juvenile stages with the goal of elucidating underlying neuropathological mechanisms and of ultimately identifying potential therapeutic targets. Wild-type third-instar larvae were irradiated with single doses of γ-radiation, and the percentage that survived to adulthood was determined. Motor function of surviving adults was examined with a climbing assay, and longevity was assessed by measuring lifespan. Neuronal cell death was assayed by using immunohistochemistry in adult brains. We also tested the sensitivity at different developmental stages by irradiating larvae at various time points. Irradiating late third-instar larvae at a dose of 20 Gy or higher impaired the motor activity of surviving adults. A dose of 40 Gy or higher resulted in a precipitous reduction in the percentage of larvae that survive to adulthood. A dose-dependent decrease in adult longevity was paralleled by a dose-dependent increase in activated Death caspase-1 (Dcp1) in adult brains. Survival to adulthood and adult lifespan were more severely impaired with decreasing larval age at the time of irradiation. Our initial survey of the Drosophila Genetic Reference Panel demonstrated that differences in genotype can confer phenotypic differences in radio-sensitivity for developmental survival and motor function. This work demonstrates the usefulness of Drosophila to model the toxic effects of radiation during development, and has the potential to unravel underlying mechanisms and to facilitate the discovery of novel therapeutic interventions.

  4. The mthA Mutation Conferring Low-Level Resistance to Streptomycin Enhances Antibiotic Production in Bacillus subtilis by Increasing the S-Adenosylmethionine Pool Size

    PubMed Central

    Tojo, Shigeo; Kim, Ji-Yun; Tanaka, Yukinori; Inaoka, Takashi; Hiraga, Yoshikazu

    2014-01-01

    Certain Strr mutations that confer low-level streptomycin resistance result in the overproduction of antibiotics by Bacillus subtilis. Using comparative genome-sequencing analysis, we successfully identified this novel mutation in B. subtilis as being located in the mthA gene, which encodes S-adenosylhomocysteine/methylthioadenosine nucleosidase, an enzyme involved in the S-adenosylmethionine (SAM)-recycling pathways. Transformation experiments showed that this mthA mutation was responsible for the acquisition of low-level streptomycin resistance and overproduction of bacilysin. The mthA mutant had an elevated level of intracellular SAM, apparently acquired by arresting SAM-recycling pathways. This increase in the SAM level was directly responsible for bacilysin overproduction, as confirmed by forced expression of the metK gene encoding SAM synthetase. The mthA mutation fully exerted its effect on antibiotic overproduction in the genetic background of rel+ but not the rel mutant, as demonstrated using an mthA relA double mutant. Strikingly, the mthA mutation activated, at the transcription level, even the dormant ability to produce another antibiotic, neotrehalosadiamine, at concentrations of 150 to 200 μg/ml, an antibiotic not produced (<1 μg/ml) by the wild-type strain. These findings establish the significance of SAM in initiating bacterial secondary metabolism. They also suggest a feasible methodology to enhance or activate antibiotic production, by introducing either the rsmG mutation to Streptomyces or the mthA mutation to eubacteria, since many eubacteria have mthA homologues. PMID:24509311

  5. Ectopic Overexpression of SlHsfA3, a Heat Stress Transcription Factor from Tomato, Confers Increased Thermotolerance and Salt Hypersensitivity in Germination in Transgenic Arabidopsis

    PubMed Central

    Li, Zhenjun; Zhang, Lili; Wang, Aoxue; Xu, Xiangyang; Li, Jingfu

    2013-01-01

    Plant heat stress transcription factors (Hsfs) are the critical components involved in mediating responses to various environmental stressors. However, the detailed roles of many plant Hsfs are far from fully understood. In this study, an Hsf (SlHsfA3) was isolated from the cultivated tomato (Solanum lycopersicum, Sl) and functionally characterized at the genetic and developmental levels. The nucleus-localized SlHsfA3 was basally and ubiquitously expressed in different plant organs. The expression of SlHsfA3 was induced dramatically by heat stress, moderately by high salinity, and slightly by drought, but was not induced by abscisic acid (ABA). The ectopic overexpression of SlHsfA3 conferred increased thermotolerance and late flowering phenotype to transgenic Arabidopsis plants. Moreover, SlHsfA3 played a negative role in controlling seed germination under salt stress. RNA-sequencing data demonstrated that a number of heat shock proteins (Hsps) and stress-associated genes were induced in Arabidopsis plants overexpressing SlHsfA3. A gel shift experiment and transient expression assays in Nicotiana benthamiana leaves demonstrated that SlHsfA3 directly activates the expression of SlHsp26.1-P and SlHsp21.5-ER. Taken together, our results suggest that SlHsfA3 behaves as a typical Hsf to contribute to plant thermotolerance. The late flowering and seed germination phenotypes and the RNA-seq data derived from SlHsfA3 overexpression lines lend more credence to the hypothesis that plant Hsfs participate in diverse physiological and biochemical processes related to adverse conditions. PMID:23349984

  6. The Chromosomal Arsenic Resistance Genes of Thiobacillus ferrooxidans Have an Unusual Arrangement and Confer Increased Arsenic and Antimony Resistance to Escherichia coli

    PubMed Central

    Butcher, Bronwyn G.; Deane, Shelly M.; Rawlings, Douglas E.

    2000-01-01

    The chromosomal arsenic resistance genes of the acidophilic, chemolithoautotrophic, biomining bacterium Thiobacillus ferrooxidans were cloned and sequenced. Homologues of four arsenic resistance genes, arsB, arsC, arsH, and a putative arsR gene, were identified. The T. ferrooxidans arsB (arsenite export) and arsC (arsenate reductase) gene products were functional when they were cloned in an Escherichia coli ars deletion mutant and conferred increased resistance to arsenite, arsenate, and antimony. Therefore, despite the fact that the ars genes originated from an obligately acidophilic bacterium, they were functional in E. coli. Although T. ferrooxidans is gram negative, its ArsC was more closely related to the ArsC molecules of gram-positive bacteria. Furthermore, a functional trxA (thioredoxin) gene was required for ArsC-mediated arsenate resistance in E. coli; this finding confirmed the gram-positive ArsC-like status of this resistance and indicated that the division of ArsC molecules based on Gram staining results is artificial. Although arsH was expressed in an E. coli-derived in vitro transcription-translation system, ArsH was not required for and did not enhance arsenic resistance in E. coli. The T. ferrooxidans ars genes were arranged in an unusual manner, and the putative arsR and arsC genes and the arsBH genes were translated in opposite directions. This divergent orientation was conserved in the four T. ferrooxidans strains investigated. PMID:10788346

  7. Ectopic overexpression of SlHsfA3, a heat stress transcription factor from tomato, confers increased thermotolerance and salt hypersensitivity in germination in transgenic Arabidopsis.

    PubMed

    Li, Zhenjun; Zhang, Lili; Wang, Aoxue; Xu, Xiangyang; Li, Jingfu

    2013-01-01

    Plant heat stress transcription factors (Hsfs) are the critical components involved in mediating responses to various environmental stressors. However, the detailed roles of many plant Hsfs are far from fully understood. In this study, an Hsf (SlHsfA3) was isolated from the cultivated tomato (Solanum lycopersicum, Sl) and functionally characterized at the genetic and developmental levels. The nucleus-localized SlHsfA3 was basally and ubiquitously expressed in different plant organs. The expression of SlHsfA3 was induced dramatically by heat stress, moderately by high salinity, and slightly by drought, but was not induced by abscisic acid (ABA). The ectopic overexpression of SlHsfA3 conferred increased thermotolerance and late flowering phenotype to transgenic Arabidopsis plants. Moreover, SlHsfA3 played a negative role in controlling seed germination under salt stress. RNA-sequencing data demonstrated that a number of heat shock proteins (Hsps) and stress-associated genes were induced in Arabidopsis plants overexpressing SlHsfA3. A gel shift experiment and transient expression assays in Nicotiana benthamiana leaves demonstrated that SlHsfA3 directly activates the expression of SlHsp26.1-P and SlHsp21.5-ER. Taken together, our results suggest that SlHsfA3 behaves as a typical Hsf to contribute to plant thermotolerance. The late flowering and seed germination phenotypes and the RNA-seq data derived from SlHsfA3 overexpression lines lend more credence to the hypothesis that plant Hsfs participate in diverse physiological and biochemical processes related to adverse conditions.

  8. The Biochemical Adaptations of Spotted Wing Drosophila (Diptera: Drosophilidae) to Fresh Fruits Reduced Fructose Concentrations and Glutathione-S Transferase Activities.

    PubMed

    Nguyen, Phuong; Kim, A-Young; Jung, Jin Kyo; Donahue, Kelly M; Jung, Chuleui; Choi, Man-Yeon; Koh, Young Ho

    2016-04-01

    Spotted wing drosophila, Drosophila suzukii Matsumura, is an invasive and economically damaging pest in Europe and North America. The females have a serrated ovipositor that enables them to infest almost all ripening small fruits. To understand the physiological and metabolic basis of spotted wing drosophila food preferences for healthy ripening fruits, we investigated the biological and biochemical characteristics of spotted wing drosophila and compared them with those of Drosophila melanogaster Meigen. We found that the susceptibility to oxidative stressors was significantly increased in spotted wing drosophila compared with those of D. melanogaster. In addition, we found that spotted wing drosophila had significantly reduced glutathione-S transferase (GST) activity and gene numbers. Furthermore, fructose concentrations found in spotted wing drosophila were significantly lower than those of D. melanogaster. Our data strongly suggest that the altered food preferences of spotted wing drosophila may stem from evolutionary adaptations to fresh foods accompanied by alterations in carbohydrate metabolism and GST activities.

  9. Conference Resolution

    NASA Astrophysics Data System (ADS)

    2009-04-01

    Since the first IUPAP International Conference on Women in Physics (Paris, March 2002) and the Second Conference (Rio de Janeiro, May 2005), progress has continued in most countries and world regions to attract girls to physics and advance women into leadership roles, and many working groups have formed. The Third Conference (Seoul, October 2008), with 283 attendees from 57 countries, was dedicated to celebrating the physics achievements of women throughout the world, networking toward new international collaborations, building each participant's capacity for career success, and aiding the formation of active regional working groups to advance women in physics. Despite the progress, women remain a small minority of the physics community in most countries.

  10. ConfChem Conference on Flipped Classroom: Reclaiming Face Time--How an Organic Chemistry Flipped Classroom Provided Access to Increased Guided Engagement

    ERIC Educational Resources Information Center

    Trogden, Bridget G.

    2015-01-01

    Students' active engagement is one of the most critical challenges to any successful learning environment. The blending of active engagement along with rich, meaningful content is necessary for chemical educators to re-examine the purpose of the chemistry classroom. The Spring 2014 ConfChem conference, Flipped Classroom, was held from May 9 to…

  11. ConfChem Conference on Flipped Classroom: Reclaiming Face Time--How an Organic Chemistry Flipped Classroom Provided Access to Increased Guided Engagement

    ERIC Educational Resources Information Center

    Trogden, Bridget G.

    2015-01-01

    Students' active engagement is one of the most critical challenges to any successful learning environment. The blending of active engagement along with rich, meaningful content is necessary for chemical educators to re-examine the purpose of the chemistry classroom. The Spring 2014 ConfChem conference, Flipped Classroom, was held from May 9 to…

  12. The Gastrodia anti-fungal protein confers increased resistance to Phytophthora root rot and the root-knot nematode in a fruit tree species

    USDA-ARS?s Scientific Manuscript database

    The Gastrodia Anti-Fungal Protein (GAFP) is a monocot mannose-binding lectin isolated from the Asiatic orchid Gastrodia elata. This protein, among others, enables the orchid to live parasitically off the basidiomycete pathogen Armillaria mellea. GAFP has been shown to confer resistance to transgenic...

  13. Proceedings of the Conference on Increasing Opportunities for Mexican American Students in Higher Education (Los Angeles Harbor College, California, May 15-17, 1969).

    ERIC Educational Resources Information Center

    Franklin, Mayer J., Ed.; And Others

    The conference was conducted in order to propose solutions to the problems that confront the Mexican American student in higher education in areas of recruitment, retention, and financial assistance. Colleges and universities from 5 Southwestern states sent teams (student, faculty member, administrator, junior college representative, high school…

  14. Rapid effects of humidity acclimation on stress resistance in Drosophila melanogaster.

    PubMed

    Aggarwal, Dau Dayal; Ranga, Poonam; Kalra, Bhawna; Parkash, Ravi; Rashkovetsky, Eugenia; Bantis, Leonidas E

    2013-09-01

    We tested the hypothesis whether developmental acclimation at ecologically relevant humidity regimes (40% and 75% RH) affects desiccation resistance of pre-adults (3rd instar larvae) and adults of Drosophila melanogaster Meigen (Diptera: Drosophilidae). Additionally, we untangled whether drought (40% RH) acclimation affects cold-tolerance in the adults of D. melanogaster. We observed that low humidity (40% RH) acclimated individuals survived significantly longer (1.6-fold) under lethal levels of desiccation stress (0-5% RH) than their counter-replicates acclimated at 75% RH. In contrast to a faster duration of development of 1st and 2nd instar larvae, 3rd instar larvae showed a delayed development at 40% RH as compared to their counterparts grown at 75% RH. Rearing to low humidity conferred an increase in bulk water, hemolymph content and dehydration tolerance, consistent with increase in desiccation resistance for replicates grown at 40% as compared to their counterparts at 75% RH. Further, we found a trade-off between the levels of carbohydrates and body lipid reserves at 40% and 75% RH. Higher levels of carbohydrates sustained longer survival under desiccation stress for individuals developed at 40% RH than their congeners at 75% RH. However, the rate of carbohydrate utilization did not differ between the individuals reared at these contrasting humidity regimes. Interestingly, our results of accelerated failure time (AFT) models showed substantial decreased death rates at a series of low temperatures (0, -2, or -4°C) for replicates acclimated at 40% RH as compared to their counter-parts at 75% RH. Therefore, our findings indicate that development to low humidity conditions constrained on multiple physiological mechanisms of water-balance, and conferred cross-tolerance towards desiccation and cold stress in D. melanogaster. Finally, we suggest that the ability of generalist Drosophila species to tolerate fluctuations in humidity might aid in their existence and

  15. Ecdysone Induction of MsrA Protects Against Oxidative Stress in Drosophila

    SciTech Connect

    Roesijadi, Guri; Rezvankhah, Saeid; Binninger, David M.; Weissbach, Herbert

    2007-03-09

    The methionine sulfoxide reductases MsrA and MsrB reduce Met(O) to Met in epimer-specific fashion. In Drosophila, the major ecdysone induced protein is MsrA, which is regulated by the EcR-USP complex. We tested Kc cells for induction of MsrA, MsrB, EcR. and CAT by ecdysone and found that MsrA and the EcR were induced by ecdysone, but MsrB and CAT were not. When we tested for resistance to 20 mM H2O2 toxicity, viability of Kc cells was reduced threefold. After pretreatment with 0.2 μM ecdysone for 48 h, then exposed to H2O2, viability of Kc cells increased to 77% of controls. The EcR-deficient L57-3-11 knockout line was not responsive to ecdysone, and H2O2 resistance of both control and ecdysone-treated L57-3-11 cells was similar to that of the ecdysone-untreated Kc cells. These results show that hormonal regulation of MsrA is implicated in conferring protection against oxidative stress in the Drosophila model.

  16. Biomedical Conferences

    NASA Technical Reports Server (NTRS)

    1976-01-01

    As a result of Biomedical Conferences, Vivo Metric Systems Co. has produced cardiac electrodes based on NASA technology. Frequently in science, one highly specialized discipline is unaware of relevant advances made in other areas. In an attempt to familiarize researchers in a variety of disciplines with medical problems and needs, NASA has sponsored conferences that bring together university scientists, practicing physicians and manufacturers of medical instruments.

  17. Modeling Human Cancers in Drosophila.

    PubMed

    Sonoshita, M; Cagan, R L

    2017-01-01

    Cancer is a complex disease that affects multiple organs. Whole-body animal models provide important insights into oncology that can lead to clinical impact. Here, we review novel concepts that Drosophila studies have established for cancer biology, drug discovery, and patient therapy. Genetic studies using Drosophila have explored the roles of oncogenes and tumor-suppressor genes that when dysregulated promote cancer formation, making Drosophila a useful model to study multiple aspects of transformation. Not limited to mechanism analyses, Drosophila has recently been showing its value in facilitating drug development. Flies offer rapid, efficient platforms by which novel classes of drugs can be identified as candidate anticancer leads. Further, we discuss the use of Drosophila as a platform to develop therapies for individual patients by modeling the tumor's genetic complexity. Drosophila provides both a classical and a novel tool to identify new therapeutics, complementing other more traditional cancer tools. © 2017 Elsevier Inc. All rights reserved.

  18. Cold acclimation wholly reorganizes the Drosophila melanogaster transcriptome and metabolome

    PubMed Central

    MacMillan, Heath A.; Knee, Jose M.; Dennis, Alice B.; Udaka, Hiroko; Marshall, Katie E.; Merritt, Thomas J. S.; Sinclair, Brent J.

    2016-01-01

    Cold tolerance is a key determinant of insect distribution and abundance, and thermal acclimation can strongly influence organismal stress tolerance phenotypes, particularly in small ectotherms like Drosophila. However, there is limited understanding of the molecular and biochemical mechanisms that confer such impressive plasticity. Here, we use high-throughput mRNA sequencing (RNA-seq) and liquid chromatography – mass spectrometry (LC-MS) to compare the transcriptomes and metabolomes of D. melanogaster acclimated as adults to warm (rearing) (21.5 °C) or cold conditions (6 °C). Cold acclimation improved cold tolerance and led to extensive biological reorganization: almost one third of the transcriptome and nearly half of the metabolome were differentially regulated. There was overlap in the metabolic pathways identified via transcriptomics and metabolomics, with proline and glutathione metabolism being the most strongly-supported metabolic pathways associated with increased cold tolerance. We discuss several new targets in the study of insect cold tolerance (e.g. dopamine signaling and Na+-driven transport), but many previously identified candidate genes and pathways (e.g. heat shock proteins, Ca2+ signaling, and ROS detoxification) were also identified in the present study, and our results are thus consistent with and extend the current understanding of the mechanisms of insect chilling tolerance. PMID:27357258

  19. Functional Gustatory Role of Chemoreceptors in Drosophila Wings.

    PubMed

    Raad, Hussein; Ferveur, Jean-François; Ledger, Neil; Capovilla, Maria; Robichon, Alain

    2016-05-17

    Neuroanatomical evidence argues for the presence of taste sensilla in Drosophila wings; however, the taste physiology of insect wings remains hypothetical, and a comprehensive link to mechanical functions, such as flight, wing flapping, and grooming, is lacking. Our data show that the sensilla of the Drosophila anterior wing margin respond to both sweet and bitter molecules through an increase in cytosolic Ca(2+) levels. Conversely, genetically modified flies presenting a wing-specific reduction in chemosensory cells show severe defects in both wing taste signaling and the exploratory guidance associated with chemodetection. In Drosophila, the chemodetection machinery includes mechanical grooming, which facilitates the contact between tastants and wing chemoreceptors, and the vibrations of flapping wings that nebulize volatile molecules as carboxylic acids. Together, these data demonstrate that the Drosophila wing chemosensory sensilla are a functional taste organ and that they may have a role in the exploration of ecological niches.

  20. Endocrine and physiological regulation of neutral fat storage in Drosophila.

    PubMed

    Lehmann, Michael

    2017-09-08

    After having revolutionized our understanding of the mechanisms of animal development, Drosophila melanogaster has more recently emerged as an equally valid genetic model in the field of animal metabolism. An increasing number of studies have revealed that many signaling pathways that control metabolism in mammals, including pathways controlled by nutrients (insulin, TOR), steroid hormone, glucagon, and hedgehog, are functionally conserved between mammals and Drosophila. In fact, genetic screens and analyses in Drosophila have identified new players and filled in gaps in the signaling networks that control metabolism. This review focuses on data that show how these networks control the formation and breakdown of triacylglycerol energy stores in the fat tissue of Drosophila. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Aging studies in Drosophila melanogaster.

    PubMed

    Sun, Yaning; Yolitz, Jason; Wang, Cecilia; Spangler, Edward; Zhan, Ming; Zou, Sige

    2013-01-01

    Drosophila is a genetically tractable system ideal for investigating the mechanisms of aging and developing interventions for promoting healthy aging. Here we describe methods commonly used in Drosophila aging research. These include basic approaches for preparation of diets and measurements of lifespan, food intake, and reproductive output. We also describe some commonly used assays to measure changes in physiological and behavioral functions of Drosophila in aging, such as stress resistance and locomotor activity.

  2. Aging Studies in Drosophila melanogaster

    PubMed Central

    Sun, Yaning; Yolitz, Jason; Wang, Cecilia; Spangler, Edward; Zhan, Ming; Zou, Sige

    2015-01-01

    Summary Drosophila is a genetically tractable system ideal for investigating the mechanisms of aging and developing interventions for promoting healthy aging. Here we describe methods commonly used in Drosophila aging research. These include basic approaches for preparation of diets and measurements of lifespan, food intake and reproductive output. We also describe some commonly used assays to measure changes in physiological and behavioral functions of Drosophila in aging, such as stress resistance and locomotor activity. PMID:23929099

  3. Innate immunity in Drosophila: Pathogens and pathways.

    PubMed

    Govind, Shubha

    2008-02-01

    Following in the footsteps of traditional developmental genetics, research over the last 15 years has shown that innate immunity against bacteria and fungi is governed largely by two NF-kappaB signal transduction pathways, Toll and IMD. Antiviral immunity appears to stem from RNA interference, whereas resistance against parasitoids is conferred by Toll signaling. The identification of these post-transcriptional regulatory mechanisms and the annotation of most Drosophila immunity genes have derived from functional genomic studies using "model" pathogens, intact animals and cell lines. The D. melanogaster host has thus provided the core information that can be used to study responses to natural microbial and metazoan pathogens as they become identified, as well as to test ideas of selection and evolutionary change. These analyses are of general importance to understanding mechanisms of other insect host-pathogen interactions and determinants of variation in host resistance.

  4. Innate immunity in Drosophila: Pathogens and pathways

    PubMed Central

    Govind, Shubha

    2009-01-01

    Following in the footsteps of traditional developmental genetics, research over the last 15 years has shown that innate immunity against bacteria and fungi is governed largely by two NF-κB signal transduction pathways, Toll and IMD. Antiviral immunity appears to stem from RNA interference, whereas resistance against parasitoids is conferred by Toll signaling. The identification of these post-transcriptional regulatory mechanisms and the annotation of most Drosophila immunity genes have derived from functional genomic studies using “model” pathogens, intact animals and cell lines. The D. melanogaster host has thus provided the core information that can be used to study responses to natural microbial and metazoan pathogens as they become identified, as well as to test ideas of selection and evolutionary change. These analyses are of general importance to understanding mechanisms of other insect host–pathogen interactions and determinants of variation in host resistance. PMID:20485470

  5. Temperature sensation in Drosophila.

    PubMed

    Barbagallo, Belinda; Garrity, Paul A

    2015-10-01

    Animals use thermosensory systems to achieve optimal temperatures for growth and reproduction and to avoid damaging extremes. Thermoregulation is particularly challenging for small animals like the fruit fly Drosophila melanogaster, whose body temperature rapidly changes in response to environmental temperature fluctuation. Recent work has uncovered some of the key molecules mediating fly thermosensation, including the Transient Receptor Potential (TRP) channels TRPA1 and Painless, and the Gustatory Receptor Gr28b, an unanticipated thermosensory regulator normally associated with a different sensory modality. There is also evidence the Drosophila phototransduction cascade may have some role in thermosensory responses. Together, the fly's diverse thermosensory molecules act in an array of functionally distinct thermosensory neurons to drive a suite of complex, and often exceptionally thermosensitive, behaviors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. The Drosophila Auditory System

    PubMed Central

    Boekhoff-Falk, Grace; Eberl, Daniel F.

    2013-01-01

    Development of a functional auditory system in Drosophila requires specification and differentiation of the chordotonal sensilla of Johnston’s organ (JO) in the antenna, correct axonal targeting to the antennal mechanosensory and motor center (AMMC) in the brain, and synaptic connections to neurons in the downstream circuit. Chordotonal development in JO is functionally complicated by structural, molecular and functional diversity that is not yet fully understood, and construction of the auditory neural circuitry is only beginning to unfold. Here we describe our current understanding of developmental and molecular mechanisms that generate the exquisite functions of the Drosophila auditory system, emphasizing recent progress and highlighting important new questions arising from research on this remarkable sensory system. PMID:24719289

  7. Sexual circuitry in Drosophila.

    PubMed

    Auer, Thomas O; Benton, Richard

    2016-06-01

    The sexual behavior of Drosophila melanogaster is an outstanding paradigm to understand the molecular and neuronal basis of sophisticated animal actions. We discuss recent advances in our knowledge of the genetic hardwiring of the underlying neuronal circuitry, and how pertinent sensory cues are differentially detected and integrated in the male and female brain. We also consider how experience influences these circuits over short timescales, and the evolution of these pathways over longer timescales to endow species-specific sexual displays and responses.

  8. Conference reports

    NASA Astrophysics Data System (ADS)

    Dongpei, Chen; Yulong, Ma

    1994-12-01

    The Ultrasonic Electronics Branch Society of the China Acoustics Society, and the Electronics Countermeasure Branch Society of the China Electronics Society held and All-China Applications Conference of Ultrasonic Electronics Devices in Electronic Countermeasures, Radar and Military Communication Technology. A total of 66 papers was received by the conference with contents relating to surface acoustic wave devices, high-frequency acoustic wave devices, acousto-optical devices, applications of devices in radar, applications of devices in electronic countermeasures, and applications of devices in military communication systems.

  9. Go Signaling in Mushroom Bodies Regulates Sleep in Drosophila

    PubMed Central

    Guo, Fang; Yi, Wei; Zhou, Mingmin; Guo, Aike

    2011-01-01

    Study Objectives: Sleep is a fundamental physiological process and its biological mechanisms are poorly understood. In Drosophila melanogaster, heterotrimeric Go protein is abundantly expressed in the brain. However, its post-developmental function has not been extensively explored. Design: Locomotor activity was measured using the Drosophila Activity Monitoring System under a 12:12 LD cycle. Sleep was defined as periods of 5 min with no recorded activity. Results: Pan-neuronal elevation of Go signaling induced quiescence accompanied by an increased arousal threshold in flies. By screening region-specific GAL4 lines, we mapped the sleep-regulatory function of Go signaling to mushroom bodies (MBs), a central brain region which modulates memory, decision making, and sleep in Drosophila. Up-regulation of Go activity in these neurons consolidated sleep while inhibition of endogenous Go via expression of Go RNAi or pertussis toxin reduced and fragmented sleep, indicating that the Drosophila sleep requirement is affected by levels of Go activity in the MBs. Genetic interaction results showed that Go signaling serves as a neuronal transmission inhibitor in a cAMP-independent pathway. Conclusion: Go signaling is a novel signaling pathway in MBs that regulates sleep in Drosophila. Citation: Guo F; Yi W; Zhou M; Guo A. Go signaling in mushroom bodies regulates sleep in drosophila. SLEEP 2011;34(3):273-281. PMID:21358844

  10. Conference Connections: Rewiring the Circuit

    ERIC Educational Resources Information Center

    Siemens, George; Tittenberger, Peter; Anderson, Terry

    2008-01-01

    Increased openness, two-way dialogue, and blurred distinctions between experts and amateurs have combined with numerous technology tools for dialogue, personal expression, networking, and community formation to "remake" conferences, influencing not only how attendees participate in but also how organizers host conferences today. (Contains 31…

  11. Conference Connections: Rewiring the Circuit

    ERIC Educational Resources Information Center

    Siemens, George; Tittenberger, Peter; Anderson, Terry

    2008-01-01

    Increased openness, two-way dialogue, and blurred distinctions between experts and amateurs have combined with numerous technology tools for dialogue, personal expression, networking, and community formation to "remake" conferences, influencing not only how attendees participate in but also how organizers host conferences today. (Contains 31…

  12. Conference Summary

    ERIC Educational Resources Information Center

    Doherty, Cait

    2009-01-01

    This article summarizes an original conference, organised by the Child Care Research Forum (http://www.qub.ac.uk/sites/ccrf/), which brought together experts from all over Northern Ireland to showcase some of the wealth of research with children and young people that is going on in the country today. Developed around the six high-level outcomes of…

  13. The conference

    Treesearch

    Gordon M. Heisler; Lee P. Herrington

    1977-01-01

    This is a report on the Conference on Metropolitan Physical Environment, held in August 1975 at Syracuse, N.Y., where some 160 scientists and planners met to discuss the use of vegetation, space, and structures to improve the amenities for people who live in metropolitan areas.

  14. Conference Space

    ERIC Educational Resources Information Center

    Tillett, Wade

    2016-01-01

    The following is an exploration of the spatial configurations (and their implications) within a typical panel session at an academic conference. The presenter initially takes up different roles and hyperbolically describes some possible messages that the spatial arrangement sends. Eventually, the presenter engages the audience members in atypical…

  15. Conference Space

    ERIC Educational Resources Information Center

    Tillett, Wade

    2016-01-01

    The following is an exploration of the spatial configurations (and their implications) within a typical panel session at an academic conference. The presenter initially takes up different roles and hyperbolically describes some possible messages that the spatial arrangement sends. Eventually, the presenter engages the audience members in atypical…

  16. The Drosophila melanogaster host model

    PubMed Central

    Igboin, Christina O.; Griffen, Ann L.; Leys, Eugene J.

    2012-01-01

    The deleterious and sometimes fatal outcomes of bacterial infectious diseases are the net result of the interactions between the pathogen and the host, and the genetically tractable fruit fly, Drosophila melanogaster, has emerged as a valuable tool for modeling the pathogen–host interactions of a wide variety of bacteria. These studies have revealed that there is a remarkable conservation of bacterial pathogenesis and host defence mechanisms between higher host organisms and Drosophila. This review presents an in-depth discussion of the Drosophila immune response, the Drosophila killing model, and the use of the model to examine bacterial–host interactions. The recent introduction of the Drosophila model into the oral microbiology field is discussed, specifically the use of the model to examine Porphyromonas gingivalis–host interactions, and finally the potential uses of this powerful model system to further elucidate oral bacterial-host interactions are addressed. PMID:22368770

  17. Grammar! A Conference Report.

    ERIC Educational Resources Information Center

    King, Lid, Ed.; Boaks, Peter, Ed.

    Papers from a conference on the teaching of grammar, particularly in second language instruction, include: "Grammar: Acquisition and Use" (Richard Johnstone); "Grammar and Communication" (Brian Page); "Linguistic Progression and Increasing Independence" (Bernardette Holmes); "La grammaire? C'est du bricolage!" ("Grammar? That's Hardware!") (Barry…

  18. Exquisite light sensitivity of Drosophila melanogaster cryptochrome.

    PubMed

    Vinayak, Pooja; Coupar, Jamie; Hughes, S Emile; Fozdar, Preeya; Kilby, Jack; Garren, Emma; Yoshii, Taishi; Hirsh, Jay

    2013-01-01

    Drosophila melanogaster shows exquisite light sensitivity for modulation of circadian functions in vivo, yet the activities of the Drosophila circadian photopigment cryptochrome (CRY) have only been observed at high light levels. We studied intensity/duration parameters for light pulse induced circadian phase shifts under dim light conditions in vivo. Flies show far greater light sensitivity than previously appreciated, and show a surprising sensitivity increase with pulse duration, implying a process of photic integration active up to at least 6 hours. The CRY target timeless (TIM) shows dim light dependent degradation in circadian pacemaker neurons that parallels phase shift amplitude, indicating that integration occurs at this step, with the strongest effect in a single identified pacemaker neuron. Our findings indicate that CRY compensates for limited light sensitivity in vivo by photon integration over extraordinarily long times, and point to select circadian pacemaker neurons as having important roles.

  19. Heat shock proteins and Drosophila aging.

    PubMed

    Tower, John

    2011-05-01

    Since their discovery in Drosophila, the heat shock proteins (Hsps) have been shown to regulate both stress resistance and life-span. Aging is characterized by increased oxidative stress and the accumulation of abnormal (malfolded) proteins, and these stresses induce Hsp gene expression through the transcription factor HSF. In addition, a subset of Hsps is induced by oxidative stress through the JNK signaling pathway and the transcription factor Foxo. The Hsps counteract the toxicity of abnormal proteins by facilitating protein refolding and turnover, and through other mechanisms including inhibition of apoptosis. The Hsps are up-regulated in tissue-specific patterns during aging, and their expression correlates with, and sometimes predicts, life span, making them ideal biomarkers of aging. The tools available for experimentally manipulating gene function and assaying healthspan in Drosophila provides an unparalleled opportunity to further study the role of Hsps in aging.

  20. Effects of space flight factors on Drosophila.

    PubMed

    Dubinin, N P; Glembotsky, Y L; Vaulina, E N; Grozdova, T Y; Kamshilova, E M; Ivaschenko, N I; Kholikova, I A; Nechitailo, G S; Mashinsky, A L; Iordanishvili, E K

    1973-01-01

    Drosophila melanogaster flies of strain D-32 were exposed aboard the Soyuz 10 spaceship. An insert with a nutritional medium and insects was placed in a small on-board thermostat (Biotherm II) providing a constant temperature (24 degrees C +/- 1 degree) for Drosophila development. The frequency of dominant lethals was determined in the females. Dominant, autosomal and sex-linked recessive lethals were estimated in hatching virgin males and females; the time of hatching was rigorously fixed. Sex-linked recessive lethals were related to certain stages of gametogenesis. The 1-5 oocyte stage showed an increased sensitivity to space-flight factors as regards the frequency of both dominant and recessive lethals.

  1. Heat shock proteins and Drosophila aging

    PubMed Central

    Tower, John

    2010-01-01

    Since their discovery in Drosophila, the heat shock proteins (Hsps) have been shown to regulate both stress resistance and life span. Aging is characterized by increased oxidative stress and the accumulation of abnormal (malfolded) proteins, and these stresses induce Hsp gene expression through the transcription factor HSF. In addition, a subset of Hsps is induced by oxidative stress through the JNK signaling pathway and the transcription factor Foxo. The Hsps counteract the toxicity of abnormal proteins by facilitating protein refolding and turnover, and through other mechanisms including inhibition of apoptosis. The Hsps are up-regulated in tissue-specific patterns during aging, and their expression correlates with, and sometimes predicts, life span, making them ideal biomarkers of aging. The tools available for experimentally manipulating gene function and assaying healthspan in Drosophila provides an unparalleled opportunity to further study the role of Hsps in aging. PMID:20840862

  2. Calcium waves occur as Drosophila oocytes activate

    PubMed Central

    Kaneuchi, Taro; Sartain, Caroline V.; Takeo, Satomi; Horner, Vanessa L.; Buehner, Norene A.; Aigaki, Toshiro; Wolfner, Mariana F.

    2015-01-01

    Egg activation is the process by which a mature oocyte becomes capable of supporting embryo development. In vertebrates and echinoderms, activation is induced by fertilization. Molecules introduced into the egg by the sperm trigger progressive release of intracellular calcium stores in the oocyte. Calcium wave(s) spread through the oocyte and induce completion of meiosis, new macromolecular synthesis, and modification of the vitelline envelope to prevent polyspermy. However, arthropod eggs activate without fertilization: in the insects examined, eggs activate as they move through the female’s reproductive tract. Here, we show that a calcium wave is, nevertheless, characteristic of egg activation in Drosophila. This calcium rise requires influx of calcium from the external environment and is induced as the egg is ovulated. Pressure on the oocyte (or swelling by the oocyte) can induce a calcium rise through the action of mechanosensitive ion channels. Visualization of calcium fluxes in activating eggs in oviducts shows a wave of increased calcium initiating at one or both oocyte poles and spreading across the oocyte. In vitro, waves also spread inward from oocyte pole(s). Wave propagation requires the IP3 system. Thus, although a fertilizing sperm is not necessary for egg activation in Drosophila, the characteristic of increased cytosolic calcium levels spreading through the egg is conserved. Because many downstream signaling effectors are conserved in Drosophila, this system offers the unique perspective of egg activation events due solely to maternal components. PMID:25564670

  3. The conferences for undergraduate women in physics

    NASA Astrophysics Data System (ADS)

    Blessing, Susan K.

    2015-12-01

    The American Physical Society Conferences for Undergraduate Women in Physics are the continuation of a grassroots collaborative effort that began in 2006. The goals of the conferences are to increase retention and improve career outcomes of undergraduate women in physics. I describe the conferences, including organization and participant response, and encourage other countries to host similar programs for their undergraduate women.

  4. Rapid spread of the defensive endosymbiont Spiroplasma in Drosophila hydei under high parasitoid wasp pressure.

    PubMed

    Xie, Jialei; Winter, Caitlyn; Winter, Lauryn; Mateos, Mariana

    2015-02-01

    Maternally transmitted endosymbionts of insects are ubiquitous in nature and play diverse roles in the ecology and evolution of their hosts. To persist in host lineages, many symbionts manipulate host reproduction to their advantage (e.g. cytoplasmic incompatibility and male-killing), or confer fitness benefits to their hosts (e.g. metabolic provisioning and defense against natural enemies). Recent studies suggest that strains of the bacterial genus Spiroplasma protect their host (flies in the genus Drosophila) against parasitoid attack. The Spiroplasma-conferred protection is partial and flies surviving a wasp attack have reduced adult longevity and fecundity. Therefore, it is unclear whether protection against wasps alone can counter Spiroplasma loss by imperfect maternal transmission and any possible fitness costs to harboring Spiroplasma. To address this question, we conducted a population cage study comparing Spiroplasma frequencies over time (host generations) under conditions of high wasp pressure and no wasp pressure. A dramatic increase of Spiroplasma prevalence was observed under high wasp pressure. In contrast, Spiroplasma prevalence in the absence of wasps did not change significantly over time; a pattern consistent with random drift. Thus, the defensive mechanism may contribute to the high prevalence of Spiroplasma in host populations despite imperfect vertical transmission. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Drosophila SLC5A11 Mediates Hunger by Regulating K(+) Channel Activity.

    PubMed

    Park, Jin-Yong; Dus, Monica; Kim, Seonil; Abu, Farhan; Kanai, Makoto I; Rudy, Bernardo; Suh, Greg S B

    2016-08-08

    Hunger is a powerful drive that stimulates food intake. Yet, the mechanism that determines how the energy deficits that result in hunger are represented in the brain and promote feeding is not well understood. We previously described SLC5A11-a sodium/solute co-transporter-like-(or cupcake) in Drosophila melanogaster, which is required for the fly to select a nutritive sugar over a sweeter nonnutritive sugar after periods of food deprivation. SLC5A11 acts on approximately 12 pairs of ellipsoid body (EB) R4 neurons to trigger the selection of nutritive sugars, but the underlying mechanism is not understood. Here, we report that the excitability of SLC5A11-expressing EB R4 neurons increases dramatically during starvation and that this increase is abolished in the SLC5A11 mutation. Artificial activation of SLC5A11-expresssing neurons is sufficient to promote feeding and hunger-driven behaviors; silencing these neurons has the opposite effect. Notably, SLC5A11 transcript levels in the brain increase significantly when flies are starved and decrease shortly after starved flies are refed. Furthermore, expression of SLC5A11 is sufficient for promoting hunger-driven behaviors and enhancing the excitability of SLC5A11-expressing neurons. SLC5A11 inhibits the function of the Drosophila KCNQ potassium channel in a heterologous expression system. Accordingly, a knockdown of dKCNQ expression in SLC5A11-expressing neurons produces hunger-driven behaviors even in fed flies, mimicking the overexpression of SLC5A11. We propose that starvation increases SLC5A11 expression, which enhances the excitability of SLC5A11-expressing neurons by suppressing dKCNQ channels, thereby conferring the hunger state.

  6. Feeding regulation in Drosophila

    PubMed Central

    Pool, Allan-Hermann; Scott, Kristin

    2014-01-01

    Neuromodulators play a key role in adjusting animal behavior based on environmental cues and internal needs. Here, we review the regulation of Drosophila feeding behavior to illustrate how neuromodulators achieve behavioral plasticity. Recent studies have made rapid progress in determining molecular and cellular mechanisms that translate the metabolic needs of the fly into changes in neuroendocrine and neuromodulatory states. These neuromodulators in turn promote or inhibit discrete feeding behavioral subprograms. This review highlights the links between physiological needs, neuromodulatory states, and feeding decisions. PMID:24937262

  7. Myc Function in Drosophila

    PubMed Central

    Gallant, Peter

    2013-01-01

    Drosophila contains a single MYC gene. Like its vertebrate homologs, it encodes a transcription factor that activates many targets, including prominently genes involved in ribosome biogenesis and translation. This activity makes Myc a central regulator of growth and/or proliferation of many cell types, such as imaginal disc cells, polyploid cells, stem cells, and blood cells. Importantly, not only does Myc act cell autonomously but it also affects the fate of adjacent cells and tissues. This potential of Myc is harnessed by many different signaling pathways, involving, among others, Wg, Dpp, Hpo, ecdysone, insulin, and mTOR. PMID:24086064

  8. Queuine metabolism and cadmium toxicity in Drosophila

    SciTech Connect

    Farkas, W.R.; Siard, T. ); Jacobson, K.B. )

    1991-03-11

    Queuine is a derivative of guanine found in the first position of the anticodon of the transfer RNAs for Asp, Asn, His and Tyr. The transcripts of these tRNAs contain a guanine in this position. This guanine is enzymatically excised and replaced by queuine. The ratio of queuine-containing or (q+) tRNA to its precursor or (q{minus}) tRNA changes throughout the Drosophila life cycle. in the egg 10% of the tRNA is (q+). During the three larval stages this ratio drops to zero. In the one day old adult it is about 10%. It has previously been shown that when flies are selected for the ability to grow in the presence of cadmium, the tolerant flies had 100% (q+) tRNA at the first day after pupation instead of 10%. However, it was not known whether the elevated level of (q+) tRNA was a coincidence or if the elevated levels of (q+) tRNA was protective. The authors explored this problem using germfree Drosophila. The first thing was to determine if Drosophila can synthesize queuine. Sterilized eggs were seeded onto sterile chemically defined medium. The flies were grown to the adult stage. This study showed that Drosophila like mammals cannot synthesize queuine. A second result of this research was the demonstration that the authors could alter the ratio of (q+) to (q{minus}) tRNA by adding exogenous queuine to the medium e.g. at 0.008 mM queuine the (q+) tRNA was 95% instead of {lt} 5% in the last instar stage. Finally, the authors investigated whether or not queuine gave protection against cadmium. The results were that when the flies were grown in the presence of 0.2 mM cadmium queuine at 0.008 mM gave a statistically significant increase in the number of survivors.

  9. The mechanical basis of Drosophila audition.

    PubMed

    Göpfert, Martin C; Robert, Daniel

    2002-05-01

    In Drosophila melanogaster, antennal hearing organs mediate the detection of conspecific songs. Combining laser Doppler vibrometry, acoustic near-field measurements and anatomical analysis, we have investigated the first steps in Drosophila audition, i.e. the conversion of acoustic energy into mechanical vibrations and the subsequent transmission of vibrations to the auditory receptors in the base of the antenna. Examination of the mechanical responses of the antennal structures established that the distal antennal parts (the funiculus and the arista) together constitute a mechanical entity, the sound receiver. Unconventionally, this receiver is asymmetric, resulting in an unusual, rotatory pattern of vibration; in the presence of sound, the arista and the funiculus together rotate about the longitudinal axis of the latter. According to the mechanical response characteristics, the antennal receiver represents a moderately damped simple harmonic oscillator. The receiver's resonance frequency increases continuously with the stimulus intensity, demonstrating the presence of a non-linear stiffness that may be introduced by the auditory sense organ. This surprising, non-linear effect is relevant for close-range acoustic communication in Drosophila; by improving antennal sensitivity at low song intensities and reducing sensitivity when intensity is high, it brings about dynamic range compression in the fly's auditory system.

  10. Deconstructing Memory in Drosophila

    PubMed Central

    Margulies, Carla; Tully, Tim; Dubnau, Josh

    2011-01-01

    Unlike most organ systems, which have evolved to maintain homeostasis, the brain has been selected to sense and adapt to environmental stimuli by constantly altering interactions in a gene network that functions within a larger neural network. This unique feature of the central nervous system provides a remarkable plasticity of behavior, but also makes experimental investigations challenging. Each experimental intervention ramifies through both gene and neural networks, resulting in unpredicted and sometimes confusing phenotypic adaptations. Experimental dissection of mechanisms underlying behavioral plasticity ultimately must accomplish an integration across many levels of biological organization, including genetic pathways acting within individual neurons, neural network interactions which feed back to gene function, and phenotypic observations at the behavioral level. This dissection will be more easily accomplished for model systems such as Drosophila, which, compared with mammals, have relatively simple and manipulable nervous systems and genomes. The evolutionary conservation of behavioral phenotype and the underlying gene function ensures that much of what we learn in such model systems will be relevant to human cognition. In this essay, we have not attempted to review the entire Drosophila memory field. Instead, we have tried to discuss particular findings that provide some level of intellectual synthesis across three levels of biological organization: behavior, neural circuitry and biochemical pathways. We have attempted to use this integrative approach to evaluate distinct mechanistic hypotheses, and to propose critical experiments that will advance this field. PMID:16139203

  11. Myoblast fusion in Drosophila

    SciTech Connect

    Haralalka, Shruti; Abmayr, Susan M.

    2010-11-01

    The body wall musculature of a Drosophila larva is composed of an intricate pattern of 30 segmentally repeated muscle fibers in each abdominal hemisegment. Each muscle fiber has unique spatial and behavioral characteristics that include its location, orientation, epidermal attachment, size and pattern of innervation. Many, if not all, of these properties are dictated by founder cells, which determine the muscle pattern and seed the fusion process. Myofibers are then derived from fusion between a specific founder cell and several fusion competent myoblasts (FCMs) fusing with as few as 3-5 FCMs in the small muscles on the most ventral side of the embryo and as many as 30 FCMs in the larger muscles on the dorsal side of the embryo. The focus of the present review is the formation of the larval muscles in the developing embryo, summarizing the major issues and players in this process. We have attempted to emphasize experimentally-validated details of the mechanism of myoblast fusion and distinguish these from the theoretically possible details that have not yet been confirmed experimentally. We also direct the interested reader to other recent reviews that discuss myoblast fusion in Drosophila, each with their own perspective on the process . With apologies, we use gene nomenclature as specified by Flybase (http://flybase.org) but provide Table 1 with alternative names and references.

  12. Drosophila pupal abdomen immunohistochemistry.

    PubMed

    Wang, Wei; Yoder, John H

    2011-10-02

    The Drosophila pupal abdomen is an established model system for the study of epithelial morphogenesis and the development of sexually dimorphic morphologies. During pupation, which spans approximately 96 hours (at 25 °C), proliferating populations of imaginal cells replace the larval epidermis to generate the adult abdominal segments. These imaginal cells, born during embryogenesis, exist as lateral pairs of histoblast nests in each abdominal segment of the larvae. Four pairs of histoblast nests give rise to the adult dorsal cuticle (anterior and posterior dorsal nests), the ventral cuticle (ventral nests) and the spiracles associated with each segment (spiracle nests). Upon puparation, these diploid cells (distinguishable by size from the larger polyploid larval epidermal cells- LECs) begin a stereotypical process of proliferation, migration and replacement of the LECs. Various molecular and genetic tools can be employed to investigate the contributions of genetic pathways involved in morphogenesis of the adult abdomen. Ultimate adult phenotypes are typically analyzed following dissection of adult abdominal cuticles. However, investigation of the underlying molecular processes requires immunohistochemical analyses of the pupal epithelium, which present unique challenges. Temporally dynamic morphogenesis and the interactions of two distinct epithelial populations (larval and imaginal) generate a fragile tissue prone to excessive cell loss during dissection and subsequent processing. We have developed methods of dissection, fixation, mounting and imaging of the Drosophila pupal abdominem epithelium for immunohistochemical studies that generate consistent high quality samples suitable for confocal or standard fluorescent microscopy.

  13. Epigenetic regulation in Drosophila.

    PubMed

    Lyko, F; Beisel, C; Marhold, J; Paro, R

    2006-01-01

    Epigenetic regulation of gene transcription relies on molecular marks like DNA methylation or histone modifications. Here we review recent advances in our understanding of epigenetic regulation in the fruit fly Drosophila melanogaster. In the past, DNA methylation research has primarily utilized mammalian model systems. However, several recent landmark discoveries have been made in other organisms. For example, the interaction between DNA methylation and histone methylation was first described in the filamentous fungus Neurospora crassa. Another example is provided by the interaction between epigenetic modifications and the RNA interference (RNAi) machinery that was first reported in the fission yeast Schizosaccharomyces pombe. Another organism with great experimental power is the fruit fly Drosophila. Epigenetic regulation by chromatin has been extensively analyzed in the fly and several of the key components have been discovered in this organism. In this chapter, we will focus on three aspects that represent the complexity of epigenetic gene regulation. (1) We will discuss the available data about the DNA methylation system, (2) we will illuminate the interaction between DNA methylation and chromatin regulation, and (3) we will provide an overview over the Polycomb system of epigenetic chromatin modifiers that has proved to be an important paradigm for a chromatin system regulating epigenetic programming.

  14. Sex-specific divergence for adaptations to dehydration stress in Drosophila kikkawai.

    PubMed

    Parkash, Ravi; Ranga, Poonam

    2013-09-01

    Several studies on diverse Drosophila species have reported higher desiccation resistance of females, but the physiological basis of such sex-specific differences has received less attention. We tested whether sex-specific differences in cuticular traits (melanic females and non-melanic males) of Drosophila kikkawai correspond with divergence in their water balance mechanisms. Our results are interesting in several respects. First, positive clinal variation in desiccation resistance was correlated with cuticular melanisation in females but with changes in cuticular lipid mass in males, despite a lack of differences between the sexes for the rate of water loss. Second, a comparative analysis of water budget showed that females of the northern population stored more body water as well as hemolymph content and exhibited greater dehydration tolerance than flies from the southern tropics. In contrast, we found no geographical variation in the males for water content and dehydration tolerance. Third, an ~10-fold increase in the rate of water loss after organic solvent treatment of male D. kikkawai suggested a role of cuticular lipids in cuticular transpiration, but had no effect in the females. Fourth, geographical differences in the storage of carbohydrate content (metabolic fuel) were observed in females but not in males. Interestingly, in females, the rate of utilization of carbohydrates did not vary geographically, but males from drier localities showed a 50% reduction compared with wetter localities. Thus, body melanisation, increased body water, hemolymph, carbohydrate content and greater dehydration tolerance confer greater desiccation resistance in females, but a reduced rate of water loss is the only possible mechanism to cope with drought stress in males. Finally, acclimated females showed a significant increase in drought resistance associated with higher trehalose content as well as dehydration tolerance, while males showed no acclimation response. Thus, sex

  15. The Dopaminergic System in the Aging Brain of Drosophila

    PubMed Central

    White, Katherine E.; Humphrey, Dickon M.; Hirth, Frank

    2010-01-01

    Drosophila models of Parkinson's disease are characterized by two principal phenotypes: the specific loss of dopaminergic (DA) neurons in the aging brain and defects in motor behavior. However, an age-related analysis of these baseline parameters in wildtype Drosophila is lacking. Here we analyzed the DA system and motor behavior in aging Drosophila. DA neurons in the adult brain can be grouped into bilateral symmetric clusters, each comprising a stereotypical number of cells. Analysis of TH > mCD8::GFP and cell type-specific MARCM clones revealed that DA neurons show cluster-specific, stereotypical projection patterns with terminal arborization in target regions that represent distinct functional areas of the adult brain. Target areas include the mushroom bodies, involved in memory formation and motivation, and the central complex, involved in the control of motor behavior, indicating that similar to the mammalian brain, DA neurons in the fly brain are involved in the regulation of specific behaviors. Behavioral analysis revealed that Drosophila show an age-related decline in startle-induced locomotion and negative geotaxis. Motion tracking however, revealed that walking activity, and exploration behavior, but not centrophobism increase at late stages of life. Analysis of TH > Dcr2, mCD8::GFP revealed a specific effect of Dcr2 expression on walking activity but not on exploratory or centrophobic behavior, indicating that the siRNA pathway may modulate distinct DA behaviors in Drosophila. Moreover, DA neurons were maintained between early- and late life, as quantified by TH > mCD8::GFP and anti-TH labeling, indicating that adult onset, age-related degeneration of DA neurons does not occur in the aging brain of Drosophila. Taken together, our data establish baseline parameters in Drosophila for the study of Parkinson's disease as well as other disorders affecting DA neurons and movement control. PMID:21165178

  16. Ex vivo genome-wide RNAi screening of the Drosophila Toll signaling pathway elicited by a larva-derived tissue extract.

    PubMed

    Kanoh, Hirotaka; Kuraishi, Takayuki; Tong, Li-Li; Watanabe, Ryo; Nagata, Shinji; Kurata, Shoichiro

    2015-11-13

    Damage-associated molecular patterns (DAMPs), so-called "danger signals," play important roles in host defense and pathophysiology in mammals and insects. In Drosophila, the Toll pathway confers damage responses during bacterial infection and improper cell-fate control. However, the intrinsic ligands and signaling mechanisms that potentiate innate immune responses remain unknown. Here, we demonstrate that a Drosophila larva-derived tissue extract strongly elicits Toll pathway activation via the Toll receptor. Using this extract, we performed ex vivo genome-wide RNAi screening in Drosophila cultured cells, and identified several signaling factors that are required for host defense and antimicrobial-peptide expression in Drosophila adults. These results suggest that our larva-derived tissue extract contains active ingredients that mediate Toll pathway activation, and the screening data will shed light on the mechanisms of damage-related Toll pathway signaling in Drosophila.

  17. Overexpression of a bHLH1 Transcription Factor of Pyrus ussuriensis Confers Enhanced Cold Tolerance and Increases Expression of Stress-Responsive Genes

    PubMed Central

    Jin, Cong; Huang, Xiao-San; Li, Kong-Qing; Yin, Hao; Li, Lei-Ting; Yao, Zheng-Hong; Zhang, Shao-Ling

    2016-01-01

    The basic helix-loop-helix (bHLH) transcription factors are involved in arrays of physiological and biochemical processes. However, knowledge concerning the functions of bHLHs in cold tolerance remains poorly understood. In this study, a PubHLH1 gene isolated from Pyrus ussuriensis was characterized for its function in cold tolerance. PubHLH1 was upregulated by cold, salt, and dehydration, with the greatest induction under cold conditions. PubHLH1 had the transactivational activity and localized in the nucleus. Ectopic expression of PubHLH1 in transgenic tobacco conferred enhanced tolerance to cold stress. The transgenic lines had higher survival rates, higher chlorophyll, higher proline contents, lower electrolyte leakages and MDA when compared with wild type (WT). In addition, transcript levels of eight genes associated with ROS scavenging, regulation, and stress defense were higher in the transgenic plants relative to the WT under the chilling stress. Taken together, these results demonstrated that PubHLH1 played a key role in cold tolerance and, at least in part, contributed to activation of stress-responsive genes. PMID:27092159

  18. Large Deletions in the pAtC58 Megaplasmid of Agrobacterium tumefaciens Can Confer Reduced Carriage Cost and Increased Expression of Virulence Genes

    PubMed Central

    Morton, Elise R.; Merritt, Peter M.; Bever, James D.; Fuqua, Clay

    2013-01-01

    The accessory plasmid pAtC58 of the common laboratory strain of Agrobacterium tumefaciens confers numerous catabolic functions and has been proposed to play a role in virulence. Genomic sequencing of evolved laboratory strains of A. tumefaciens revealed the presence of multiple deletion events in the At plasmid, with reductions in plasmid size ranging from 25% to 30% (115–194 kb). Flanking both ends of the sites of these deletions is a short-nucleotide repeat sequence that is in a single copy in the deleted plasmids, characteristic of a phage- or transposon-mediated deletion event. This repeat sequence is widespread throughout the C58 genome, but concentrated on the At plasmid, suggesting its frequency to be nonrandom. In this study, we assess the prevalence of the larger of these deletions in multiple C58 derivatives and characterize its functional significance. We find that in addition to elevating virulence gene expression, this deletion is associated with a significantly reduced carriage cost to the cell. These observations are a clear demonstration of the dynamic nature of the bacterial genome and suggest a mechanism for genetic plasticity of these costly but otherwise stable plasmids. Additionally, this phenomenon could be the basis for some of the dramatic recombination events so ubiquitous within and among megaplasmids. PMID:23783172

  19. Extension of Drosophila lifespan by cinnamon through a sex-specific dependence on the insulin receptor substrate chico

    PubMed Central

    Schriner, Samuel E.; Kuramada, Steven; Lopez, Terry E.; Truong, Stephanie; Pham, Andrew; Jafari, Mahtab

    2015-01-01

    Cinnamon is a spice commonly used worldwide to flavor desserts, fruits, cereals, breads, and meats. Numerous health benefits have been attributed to its consumption, including the recent suggestion that it may decrease blood glucose levels in people with diabetes. Insulin signaling is an integral pathway regulating the lifespan of laboratory organisms, such as worms, flies, and mice. We posited that if cinnamon truly improved the clinical signs of diabetes in people that it would also act on insulin signaling in laboratory organisms and increase lifespan. We found that cinnamon did extend lifespan in the fruit fly, Drosophila melanogaster. However, it had no effect on the expression levels of the 3 aging-related Drosophila insulin-like peptides nor did it alter sugar, fat, or soluble protein levels, as would be predicted. In addition, cinnamon exhibited no protective effects in males against oxidative challenges. However, in females it did confer a protective effect against paraquat, but sensitized them to iron. Cinnamon provided no protective effect against desiccation and starvation in females, but sensitized males to both. Interestingly, cinnamon protected both sexes against cold, sensitized both to heat, and elevated HSP70 expression levels. We also found that cinnamon required the insulin receptor substrate to extend lifespan in males, but not females. We conclude that cinnamon does not extend lifespan by improving stress tolerance in general, though it does act, at least in part, through insulin signaling. PMID:25456850

  20. Extension of Drosophila lifespan by cinnamon through a sex-specific dependence on the insulin receptor substrate chico.

    PubMed

    Schriner, Samuel E; Kuramada, Steven; Lopez, Terry E; Truong, Stephanie; Pham, Andrew; Jafari, Mahtab

    2014-12-01

    Cinnamon is a spice commonly used worldwide to flavor desserts, fruits, cereals, breads, and meats. Numerous health benefits have been attributed to its consumption, including the recent suggestion that it may decrease blood glucose levels in people with diabetes. Insulin signaling is an integral pathway regulating the lifespan of laboratory organisms, such as worms, flies, and mice. We posited that if cinnamon truly improved the clinical signs of diabetes in people that it would also act on insulin signaling in laboratory organisms and increase lifespan. We found that cinnamon did extend lifespan in the fruit fly, Drosophila melanogaster. However, it had no effect on the expression levels of the 3 aging-related Drosophila insulin-like peptides nor did it alter sugar, fat, or soluble protein levels, as would be predicted. In addition, cinnamon exhibited no protective effects in males against oxidative challenges. However, in females it did confer a protective effect against paraquat, but sensitized them to iron. Cinnamon provided no protective effect against desiccation and starvation in females, but sensitized males to both. Interestingly, cinnamon protected both sexes against cold, sensitized both to heat, and elevated HSP70 expression levels. We also found that cinnamon required the insulin receptor substrate to extend lifespan in males, but not females. We conclude that cinnamon does not extend lifespan by improving stress tolerance in general, though it does act, at least in part, through insulin signaling. Published by Elsevier Inc.

  1. Transcriptional regulation during Drosophila spermatogenesis

    PubMed Central

    Lim, Cindy; Tarayrah, Lama; Chen, Xin

    2012-01-01

    Drosophila spermatogenesis has become a paradigmatic system for the study of mechanisms that regulate adult stem cell maintenance, proliferation and differentiation. The dramatic cellular differentiation process from germline stem cell (GSC) to mature sperm is accompanied by dynamic changes in gene expression, which are regulated at transcriptional, post-transcriptional (including translational) and post-translational levels. Post-transcriptional regulation has been proposed as a unique feature of germ cells. However, recent studies have provided new insights into transcriptional regulation during Drosophila spermatogenesis. Both signaling pathways and epigenetic mechanisms act to orchestrate the transcriptional regulation of distinct genes at different germ cell differentiation stages. Many of the regulatory pathways that control male gamete differentiation in Drosophila are conserved in mammals. Therefore, studies using Drosophila spermatogenesis will provide insight into the molecular mechanisms that regulate mammalian germ cell differentiation pathways. PMID:23087835

  2. Next conference

    NASA Astrophysics Data System (ADS)

    Hexemer, Alexander; Toney, Michael F.

    2010-11-01

    After the successful conference on Synchrotron Radiation in Polymer Science (SRPS) in Rolduc Abbey (the Netherlands), we are now looking forward to the next meeting in this topical series started in 1995 by H G Zachmann, one of the pioneers of the use of synchrotron radiation techniques in polymer science. Earlier meetings were held in Hamburg (1995), Sheffield (2002), Kyoto (2006), and Rolduc (2009). In September of 2012 the Synchrotron Radiation and Polymer Science V conferences will be organized in a joint effort by the SLAC National Accelerator Laboratory and Lawrence Berkeley National Laboratory. Stanford Linear Accelerator Laboratory Stanford Linear Accelerator Laboratory Advanced Light Source at LBL Advanced Light Source at LBL The conference will be organised in the heart of beautiful San Francisco. The program will consist of invited and contributed lectures divided in sessions on the use of synchrotron SAXS/WAXD, imaging and tomography, soft x-rays, x-ray spectroscopy, GISAXS and reflectivity, micro-beams and hyphenated techniques in polymer science. Poster contributions are more than welcome and will be highlighted during the poster sessions. Visits to both SLAC as well as LBL will be organised. San Francisco can easily be reached. It is served by two major international airports San Francisco International Airport and Oakland International Airport. Both are being served by most major airlines with easy connections to Europe and Asia as well as national destinations. Both also boast excellent connections to San Francisco city centre. We are looking forward to seeing you in the vibrant city by the Bay in September 2012. Golden gate bridge Alexander Hexemer Lawrence Berkeley National Laboratory, Advanced Light Source, Berkeley, CA 94720, USA Michael F Toney Stanford Synchrotron Radiation Lightsource, Menlo Pk, CA 94025, USA E-mail: ahexemer@lbl.gov, mftoney@slac.stanford.edu

  3. Conferences revisited

    NASA Astrophysics Data System (ADS)

    Radcliffe, Jonathan

    2008-08-01

    Way back in the mid-1990s, as a young PhD student, I wrote a Lateral Thoughts article about my first experience of an academic conference (Physics World 1994 October p80). It was a peach of a trip - most of the lab decamped to Grenoble for a week of great weather, beautiful scenery and, of course, the physics. A whole new community was there for me to see in action, and the internationality of it all helped us to forget about England's non-appearance in the 1994 World Cup finals.

  4. Review: Thermal preference in Drosophila

    PubMed Central

    Dillon, Michael E.; Wang, George; Garrity, Paul A.; Huey, Raymond B.

    2009-01-01

    Environmental temperature strongly affects physiology of ectotherms. Small ectotherms, like Drosophila, cannot endogenously regulate body temperature so must rely on behavior to maintain body temperature within a physiologically permissive range. Here we review what is known about Drosophila thermal preference. Work on thermal behavior in this group is particularly exciting because it provides the opportunity to connect genes to neuromolecular mechanisms to behavior to fitness in the wild. PMID:20161211

  5. Cytoplasmic myosin from Drosophila melanogaster

    PubMed Central

    1986-01-01

    Myosin is identified and purified from three different established Drosophila melanogaster cell lines (Schneider's lines 2 and 3 and Kc). Purification entails lysis in a low salt, sucrose buffer that contains ATP, chromatography on DEAE-cellulose, precipitation with actin in the absence of ATP, gel filtration in a discontinuous KI-KCl buffer system, and hydroxylapatite chromatography. Yield of pure cytoplasmic myosin is 5-10%. This protein is identified as myosin by its cross-reactivity with two monoclonal antibodies against human platelet myosin, the molecular weight of its heavy chain, its two light chains, its behavior on gel filtration, its ATP-dependent affinity for actin, its characteristic ATPase activity, its molecular morphology as demonstrated by platinum shadowing, and its ability to form bipolar filaments. The molecular weight of the cytoplasmic myosin's light chains and peptide mapping and immunochemical analysis of its heavy chains demonstrate that this myosin, purified from Drosophila cell lines, is distinct from Drosophila muscle myosin. Two-dimensional thin layer maps of complete proteolytic digests of iodinated muscle and cytoplasmic myosin heavy chains demonstrate that, while the two myosins have some tryptic and alpha-chymotryptic peptides in common, most peptides migrate with unique mobility. One-dimensional peptide maps of SDS PAGE purified myosin heavy chain confirm these structural data. Polyclonal antiserum raised and reacted against Drosophila myosin isolated from cell lines cross-reacts only weakly with Drosophila muscle myosin isolated from the thoraces of adult Drosophila. Polyclonal antiserum raised against Drosophila muscle myosin behaves in a reciprocal fashion. Taken together our data suggest that the myosin purified from Drosophila cell lines is a bona fide cytoplasmic myosin and is very likely the product of a different myosin gene than the muscle myosin heavy chain gene that has been previously identified and characterized. PMID

  6. Enhancement of presynaptic performance in transgenic Drosophila overexpressing heat shock protein Hsp70.

    PubMed

    Karunanithi, Shanker; Barclay, Jeffrey W; Brown, Ian R; Robertson, R Meldrum; Atwood, Harold L

    2002-04-01

    Prior heat shock confers protection to Drosophila synapses during subsequent heat stress by stabilizing quantal size and reducing the decline of quantal emission at individual synaptic boutons. The major heat shock protein Hsp70, which is strongly induced by high temperatures in Drosophila, may be responsible for this synaptic protection. To test this hypothesis, we investigated synaptic protection and stabilization at larval neuromuscular junctions of transgenic Drosophila which produce more than the normal amount of Hsp70 in response to heat shock. Overexpression of Hsp70 coincides with enhanced protection of presynaptic performance, assayed by measuring mean quantal content and percentage success of transmission. Quantal size was not selectively altered, indicating no effects of overexpression on postsynaptic performance. Thus, presynaptic mechanisms can be protected by manipulating levels of Hsp70, which would provide stability to neural circuits otherwise susceptible to heat stress. Copyright 2002 Wiley-Liss, Inc.

  7. Tequila Regulates Insulin-Like Signaling and Extends Life Span in Drosophila melanogaster.

    PubMed

    Huang, Cheng-Wen; Wang, Horng-Dar; Bai, Hua; Wu, Ming-Shiang; Yen, Jui-Hung; Tatar, Marc; Fu, Tsai-Feng; Wang, Pei-Yu

    2015-12-01

    The aging process is a universal phenomenon shared by all living organisms. The identification of longevity genes is important in that the study of these genes is likely to yield significant insights into human senescence. In this study, we have identified Tequila as a novel candidate gene involved in the regulation of longevity in Drosophila melanogaster. We have found that a hypomorphic mutation of Tequila (Teq(f01792)), as well as cell-specific downregulation of Tequila in insulin-producing neurons of the fly, significantly extends life span. Tequila deficiency-induced life-span extension is likely to be associated with reduced insulin-like signaling, because Tequila mutant flies display several common phenotypes of insulin dysregulation, including reduced circulating Drosophila insulin-like peptide 2 (Dilp2), reduced Akt phosphorylation, reduced body size, and altered glucose homeostasis. These observations suggest that Tequila may confer life-span extension by acting as a modulator of Drosophila insulin-like signaling.

  8. Single Nucleotide Polymorphism Markers for Genetic Mapping in Drosophila melanogaster

    PubMed Central

    Hoskins, Roger A.; Phan, Alexander C.; Naeemuddin, Mohammed; Mapa, Felipa A.; Ruddy, David A.; Ryan, Jessica J.; Young, Lynn M.; Wells, Trent; Kopczynski, Casey; Ellis, Michael C.

    2001-01-01

    For nearly a century, genetic analysis in Drosophila melanogaster has been a powerful tool for analyzing gene function, yet Drosophila lacks the molecular genetic mapping tools that recently have revolutionized human, mouse, and plant genetics. Here, we describe the systematic characterization of a dense set of molecular markers in Drosophila by using a sequence tagged site-based physical map of the genome. We identify 474 biallelic markers in standard laboratory strains of Drosophila that span the genome. Most of these markers are single nucleotide polymorphisms and sequences for these variants are provided in an accessible format. The average density of the new markers is one per 225 kb on the autosomes and one per megabase on the X chromosome. We include in this survey a set of P-element strains that provide additional use for high-resolution mapping. We show one application of the new markers in a simple set of crosses to map a mutation in the hedgehog gene to an interval of <1 Mb. This new map resource significantly increases the efficiency and resolution of recombination mapping and will be of immediate value to the Drosophila research community. PMID:11381036

  9. Optical calcium imaging in the nervous system of Drosophila melanogaster.

    PubMed

    Riemensperger, Thomas; Pech, Ulrike; Dipt, Shubham; Fiala, André

    2012-08-01

    Drosophila melanogaster is one of the best-studied model organisms in biology, mainly because of the versatility of methods by which heredity and specific expression of genes can be traced and manipulated. Sophisticated genetic tools have been developed to express transgenes in selected cell types, and these techniques can be utilized to target DNA-encoded fluorescence probes to genetically defined subsets of neurons. Neuroscientists make use of this approach to monitor the activity of restricted types or subsets of neurons in the brain and the peripheral nervous system. Since membrane depolarization is typically accompanied by an increase in intracellular calcium ions, calcium-sensitive fluorescence proteins provide favorable tools to monitor the spatio-temporal activity across groups of neurons. Here we describe approaches to perform optical calcium imaging in Drosophila in consideration of various calcium sensors and expression systems. In addition, we outline by way of examples for which particular neuronal systems in Drosophila optical calcium imaging have been used. Finally, we exemplify briefly how optical calcium imaging in the brain of Drosophila can be carried out in practice. Drosophila provides an excellent model organism to combine genetic expression systems with optical calcium imaging in order to investigate principles of sensory coding, neuronal plasticity, and processing of neuronal information underlying behavior. This article is part of a Special Issue entitled Biochemical, Biophysical and Genetic Approaches to Intracellular Calcium Signaling. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Single nucleotide polymorphism markers for genetic mapping in Drosophila melanogaster

    SciTech Connect

    Hoskins, Roger A.; Phan, Alexander C.; Naeemuddin, Mohammed; Mapa, Felipa A.; Ruddy, David A.; Ryan, Jessica J.; Young, Lynn M.; Wells, Trent; Kopczynski, Casey; Ellis, Michael C.

    2001-04-16

    For nearly a century, genetic analysis in Drosophila melanogaster has been a powerful tool for analyzing gene function, yet Drosophila lacks the molecular genetic mapping tools that have recently revolutionized human, mouse and plant genetics. Here, we describe the systematic characterization of a dense set of molecular markers in Drosophila using an STS-based physical map of the genome. We identify 474 biallelic markers in standard laboratory strains of Drosophila that the genome. The majority of these markers are single nucleotide polymorphisms (SNPs) and sequences for these variants are provided in an accessible format. The average density of the new markers is 1 marker per 225 kb on the autosomes and 1 marker per 1 Mb on the X chromosome. We include in this survey a set of P-element strains that provide additional utility for high-resolution mapping. We demonstrate one application of the new markers in a simple set of crosses to map a mutation in the hedgehog gene to an interval of <1 Mb. This new map resource significantly increases the efficiency and resolution of recombination mapping and will be of immediate value to the Drosophila research community.

  11. Go signaling in mushroom bodies regulates sleep in Drosophila.

    PubMed

    Guo, Fang; Yi, Wei; Zhou, Mingmin; Guo, Aike

    2011-03-01

    Sleep is a fundamental physiological process and its biological mechanisms are poorly understood. In Drosophila melanogaster, heterotrimeric Go protein is abundantly expressed in the brain. However, its post-developmental function has not been extensively explored. Locomotor activity was measured using the Drosophila Activity Monitoring System under a 12:12 LD cycle. Sleep was defined as periods of 5 min with no recorded activity. Pan-neuronal elevation of Go signaling induced quiescence accompanied by an increased arousal threshold in flies. By screening region-specific GAL4 lines, we mapped the sleep-regulatory function of Go signaling to mushroom bodies (MBs), a central brain region which modulates memory, decision making, and sleep in Drosophila. Up-regulation of Go activity in these neurons consolidated sleep while inhibition of endogenous Go via expression of Go RNAi or pertussis toxin reduced and fragmented sleep, indicating that the Drosophila sleep requirement is affected by levels of Go activity in the MBs. Genetic interaction results showed that Go signaling serves as a neuronal transmission inhibitor in a cAMP-independent pathway. Go signaling is a novel signaling pathway in MBs that regulates sleep in Drosophila.

  12. Bioimage Informatics in the context of Drosophila research.

    PubMed

    Jug, Florian; Pietzsch, Tobias; Preibisch, Stephan; Tomancak, Pavel

    2014-06-15

    Modern biological research relies heavily on microscopic imaging. The advanced genetic toolkit of Drosophila makes it possible to label molecular and cellular components with unprecedented level of specificity necessitating the application of the most sophisticated imaging technologies. Imaging in Drosophila spans all scales from single molecules to the entire populations of adult organisms, from electron microscopy to live imaging of developmental processes. As the imaging approaches become more complex and ambitious, there is an increasing need for quantitative, computer-mediated image processing and analysis to make sense of the imagery. Bioimage Informatics is an emerging research field that covers all aspects of biological image analysis from data handling, through processing, to quantitative measurements, analysis and data presentation. Some of the most advanced, large scale projects, combining cutting edge imaging with complex bioimage informatics pipelines, are realized in the Drosophila research community. In this review, we discuss the current research in biological image analysis specifically relevant to the type of systems level image datasets that are uniquely available for the Drosophila model system. We focus on how state-of-the-art computer vision algorithms are impacting the ability of Drosophila researchers to analyze biological systems in space and time. We pay particular attention to how these algorithmic advances from computer science are made usable to practicing biologists through open source platforms and how biologists can themselves participate in their further development.

  13. Transmembrane channel-like (tmc) gene regulates Drosophila larval locomotion

    PubMed Central

    Guo, Yanmeng; Wang, Yuping; Zhang, Wei; Meltzer, Shan; Zanini, Damiano; Yu, Yue; Li, Jiefu; Cheng, Tong; Guo, Zhenhao; Wang, Qingxiu; Jacobs, Julie S.; Sharma, Yashoda; Eberl, Daniel F.; Göpfert, Martin C.; Jan, Lily Yeh; Jan, Yuh Nung; Wang, Zuoren

    2016-01-01

    Drosophila larval locomotion, which entails rhythmic body contractions, is controlled by sensory feedback from proprioceptors. The molecular mechanisms mediating this feedback are little understood. By using genetic knock-in and immunostaining, we found that the Drosophila melanogaster transmembrane channel-like (tmc) gene is expressed in the larval class I and class II dendritic arborization (da) neurons and bipolar dendrite (bd) neurons, both of which are known to provide sensory feedback for larval locomotion. Larvae with knockdown or loss of tmc function displayed reduced crawling speeds, increased head cast frequencies, and enhanced backward locomotion. Expressing Drosophila TMC or mammalian TMC1 and/or TMC2 in the tmc-positive neurons rescued these mutant phenotypes. Bending of the larval body activated the tmc-positive neurons, and in tmc mutants this bending response was impaired. This implicates TMC’s roles in Drosophila proprioception and the sensory control of larval locomotion. It also provides evidence for a functional conservation between Drosophila and mammalian TMCs. PMID:27298354

  14. Cytokines in Drosophila immunity.

    PubMed

    Vanha-Aho, Leena-Maija; Valanne, Susanna; Rämet, Mika

    2016-02-01

    Cytokines are a large and diverse group of small proteins that can affect many biological processes, but most commonly cytokines are known as mediators of the immune response. In the event of an infection, cytokines are produced in response to an immune stimulus, and they function as key regulators of the immune response. Cytokines come in many shapes and sizes, and although they vary greatly in structure, their functions have been well conserved in evolution. The immune signaling pathways that respond to cytokines are remarkably conserved from fly to man. Therefore, Drosophila melanogaster, provides an excellent platform for studying the biology and function of cytokines. In this review, we will describe the cytokines and cytokine-like molecules found in the fly and discuss their roles in host immunity. Copyright © 2015 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  15. Transposable elements in Drosophila

    PubMed Central

    McCullers, Tabitha J.; Steiniger, Mindy

    2017-01-01

    ABSTRACT Transposable elements (TEs) are mobile genetic elements that can mobilize within host genomes. As TEs comprise more than 40% of the human genome and are linked to numerous diseases, understanding their mechanisms of mobilization and regulation is important. Drosophila melanogaster is an ideal model organism for the study of eukaryotic TEs as its genome contains a diverse array of active TEs. TEs universally impact host genome size via transposition and deletion events, but may also adopt unique functional roles in host organisms. There are 2 main classes of TEs: DNA transposons and retrotransposons. These classes are further divided into subgroups of TEs with unique structural and functional characteristics, demonstrating the significant variability among these elements. Despite this variability, D. melanogaster and other eukaryotic organisms utilize conserved mechanisms to regulate TEs. This review focuses on the transposition mechanisms and regulatory pathways of TEs, and their functional roles in D. melanogaster. PMID:28580197

  16. Sexual Behavior of Drosophila suzukii.

    PubMed

    Revadi, Santosh; Lebreton, Sébastien; Witzgall, Peter; Anfora, Gianfranco; Dekker, Teun; Becher, Paul G

    2015-03-09

    A high reproductive potential is one reason for the rapid spread of Drosophila suzukii in Europe and in the United States. In order to identify mechanisms that mediate mating and reproduction in D. suzukii we studied the fly's reproductive behavior, diurnal mating activity and sexual maturation. Furthermore, we studied the change of female cuticular hydrocarbons (CHCs) with age and conducted a preliminary investigation on the role of female-derived chemical signals in male mating behavior. Sexual behavior in D. suzukii is characterized by distinct elements of male courtship leading to female acceptance for mating. Time of day and age modulate D. suzukii mating activity. As with other drosophilids, female sexual maturity is paralleled by a quantitative increase in CHCs. Neither female CHCs nor other olfactory signals were required to induce male courtship, however, presence of those signals significantly increased male sexual behavior. With this pilot study we hope to stimulate research on the reproductive biology of D. suzukii, which is relevant for the development of pest management tools.

  17. Sexual Behavior of Drosophila suzukii

    PubMed Central

    Revadi, Santosh; Lebreton, Sébastien; Witzgall, Peter; Anfora, Gianfranco; Dekker, Teun; Becher, Paul G.

    2015-01-01

    A high reproductive potential is one reason for the rapid spread of Drosophila suzukii in Europe and in the United States. In order to identify mechanisms that mediate mating and reproduction in D. suzukii we studied the fly’s reproductive behavior, diurnal mating activity and sexual maturation. Furthermore, we studied the change of female cuticular hydrocarbons (CHCs) with age and conducted a preliminary investigation on the role of female-derived chemical signals in male mating behavior. Sexual behavior in D. suzukii is characterized by distinct elements of male courtship leading to female acceptance for mating. Time of day and age modulate D. suzukii mating activity. As with other drosophilids, female sexual maturity is paralleled by a quantitative increase in CHCs. Neither female CHCs nor other olfactory signals were required to induce male courtship, however, presence of those signals significantly increased male sexual behavior. With this pilot study we hope to stimulate research on the reproductive biology of D. suzukii, which is relevant for the development of pest management tools. PMID:26463074

  18. Optogenetics in Drosophila Neuroscience.

    PubMed

    Riemensperger, Thomas; Kittel, Robert J; Fiala, André

    2016-01-01

    Optogenetic techniques enable one to target specific neurons with light-sensitive proteins, e.g., ion channels, ion pumps, or enzymes, and to manipulate their physiological state through illumination. Such artificial interference with selected elements of complex neuronal circuits can help to determine causal relationships between neuronal activity and the effect on the functioning of neuronal circuits controlling animal behavior. The advantages of optogenetics can best be exploited in genetically tractable animals whose nervous systems are, on the one hand, small enough in terms of cell numbers and to a certain degree stereotypically organized, such that distinct and identifiable neurons can be targeted reproducibly. On the other hand, the neuronal circuitry and the behavioral repertoire should be complex enough to enable one to address interesting questions. The fruit fly Drosophila melanogaster is a favorable model organism in this regard. However, the application of optogenetic tools to depolarize or hyperpolarize neurons through light-induced ionic currents has been difficult in adult flies. Only recently, several variants of Channelrhodopsin-2 (ChR2) have been introduced that provide sufficient light sensitivity, expression, and stability to depolarize central brain neurons efficiently in adult Drosophila. Here, we focus on the version currently providing highest photostimulation efficiency, ChR2-XXL. We exemplify the use of this optogenetic tool by applying it to a widely used aversive olfactory learning paradigm. Optogenetic activation of a population of dopamine-releasing neurons mimics the reinforcing properties of a punitive electric shock typically used as an unconditioned stimulus. In temporal coincidence with an odor stimulus this artificially induced neuronal activity causes learning of the odor signal, thereby creating a light-induced memory.

  19. The developmental transcriptome of Drosophila melanogaster

    SciTech Connect

    University of Connecticut; Graveley, Brenton R.; Brooks, Angela N.; Carlson, Joseph W.; Duff, Michael O.; Landolin, Jane M.; Yang, Li; Artieri, Carlo G.; van Baren, Marijke J.; Boley, Nathan; Booth, Benjamin W.; Brown, James B.; Cherbas, Lucy; Davis, Carrie A.; Dobin, Alex; Li, Renhua; Lin, Wei; Malone, John H.; Mattiuzzo, Nicolas R.; Miller, David; Sturgill, David; Tuch, Brian B.; Zaleski, Chris; Zhang, Dayu; Blanchette, Marco; Dudoit, Sandrine; Eads, Brian; Green, Richard E.; Hammonds, Ann; Jiang, Lichun; Kapranov, Phil; Langton, Laura; Perrimon, Norbert; Sandler, Jeremy E.; Wan, Kenneth H.; Willingham, Aarron; Zhang, Yu; Zou, Yi; Andrews, Justen; Bicke, Peter J.; Brenner, Steven E.; Brent, Michael R.; Cherbas, Peter; Gingeras, Thomas R.; Hoskins, Roger A.; Kaufman, Thomas C.; Oliver, Brian; Celniker, Susan E.

    2010-12-02

    Drosophila melanogaster is one of the most well studied genetic model organisms; nonetheless, its genome still contains unannotated coding and non-coding genes, transcripts, exons and RNA editing sites. Full discovery and annotation are pre-requisites for understanding how the regulation of transcription, splicing and RNA editing directs the development of this complex organism. Here we used RNA-Seq, tiling microarrays and cDNA sequencing to explore the transcriptome in 30 distinct developmental stages. We identified 111,195 new elements, including thousands of genes, coding and non-coding transcripts, exons, splicing and editing events, and inferred protein isoforms that previously eluded discovery using established experimental, prediction and conservation-based approaches. These data substantially expand the number of known transcribed elements in the Drosophila genome and provide a high-resolution view of transcriptome dynamics throughout development. Drosophila melanogaster is an important non-mammalian model system that has had a critical role in basic biological discoveries, such as identifying chromosomes as the carriers of genetic information and uncovering the role of genes in development. Because it shares a substantial genic content with humans, Drosophila is increasingly used as a translational model for human development, homeostasis and disease. High-quality maps are needed for all functional genomic elements. Previous studies demonstrated that a rich collection of genes is deployed during the life cycle of the fly. Although expression profiling using microarrays has revealed the expression of, 13,000 annotated genes, it is difficult to map splice junctions and individual base modifications generated by RNA editing using such approaches. Single-base resolution is essential to define precisely the elements that comprise the Drosophila transcriptome. Estimates of the number of transcript isoforms are less accurate than estimates of the number of genes

  20. Wolbachia-Mediated Antiviral Protection in Drosophila Larvae and Adults following Oral Infection

    PubMed Central

    Stevanovic, Aleksej L.; Arnold, Pieter A.

    2015-01-01

    Understanding viral dynamics in arthropods is of great importance when designing models to describe how viral spread can influence arthropod populations. The endosymbiotic bacterium Wolbachia spp., which is present in up to 40% of all insect species, has the ability to alter viral dynamics in both Drosophila spp. and mosquitoes, a feature that in mosquitoes may be utilized to limit spread of important arboviruses. To understand the potential effect of Wolbachia on viral dynamics in nature, it is important to consider the impact of natural routes of virus infection on Wolbachia antiviral effects. Using adult Drosophila strains, we show here that Drosophila-Wolbachia associations that have previously been shown to confer antiviral protection following systemic viral infection also confer protection against virus-induced mortality following oral exposure to Drosophila C virus in adults. Interestingly, a different pattern was observed when the same fly lines were challenged with the virus when still larvae. Analysis of the four Drosophila-Wolbachia associations that were protective in adults indicated that only the w1118-wMelPop association conferred protection in larvae following oral delivery of the virus. Analysis of Wolbachia density using quantitative PCR (qPCR) showed that a high Wolbachia density was congruent with antiviral protection in both adults and larvae. This study indicates that Wolbachia-mediated protection may vary between larval and adult stages of a given Wolbachia-host combination and that the variations in susceptibility by life stage correspond with Wolbachia density. The differences in the outcome of virus infection are likely to influence viral dynamics in Wolbachia-infected insect populations in nature and could also have important implications for the transmission of arboviruses in mosquito populations. PMID:26407882

  1. Wolbachia-mediated antiviral protection in Drosophila larvae and adults following oral infection.

    PubMed

    Stevanovic, Aleksej L; Arnold, Pieter A; Johnson, Karyn N

    2015-12-01

    Understanding viral dynamics in arthropods is of great importance when designing models to describe how viral spread can influence arthropod populations. The endosymbiotic bacterium Wolbachia spp., which is present in up to 40% of all insect species, has the ability to alter viral dynamics in both Drosophila spp. and mosquitoes, a feature that in mosquitoes may be utilized to limit spread of important arboviruses. To understand the potential effect of Wolbachia on viral dynamics in nature, it is important to consider the impact of natural routes of virus infection on Wolbachia antiviral effects. Using adult Drosophila strains, we show here that Drosophila-Wolbachia associations that have previously been shown to confer antiviral protection following systemic viral infection also confer protection against virus-induced mortality following oral exposure to Drosophila C virus in adults. Interestingly, a different pattern was observed when the same fly lines were challenged with the virus when still larvae. Analysis of the four Drosophila-Wolbachia associations that were protective in adults indicated that only the w1118-wMelPop association conferred protection in larvae following oral delivery of the virus. Analysis of Wolbachia density using quantitative PCR (qPCR) showed that a high Wolbachia density was congruent with antiviral protection in both adults and larvae. This study indicates that Wolbachia-mediated protection may vary between larval and adult stages of a given Wolbachia-host combination and that the variations in susceptibility by life stage correspond with Wolbachia density. The differences in the outcome of virus infection are likely to influence viral dynamics in Wolbachia-infected insect populations in nature and could also have important implications for the transmission of arboviruses in mosquito populations. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  2. Drosophila chem mutations disrupt epithelial polarity in Drosophila embryos

    PubMed Central

    Zamudio-Arroyo, José M.

    2016-01-01

    Drosophila embryogenesis has proven to be an extremely powerful system for developmental gene discovery and characterization. We isolated five new EMS-induced alleles that do not complement the l(3R)5G83 lethal line isolated in the Nüsslein-Volhard and Wieschaus screens. We have named this locus chem. Lethality of the new alleles as homozygous zygotic mutants is not completely penetrant, and they have an extended phenocritical period. Like the original allele, a fraction of mutant embryos die with cuticular defects, notably head involution and dorsal closure defects. Embryonic defects are much more extreme in germline clones, where the majority of mutant embryos die during embryogenesis and do not form cuticle, implying a strong chem maternal contribution. chem mutations genetically interact with mutations in cytoskeletal genes (arm) and with mutations in the epithelial polarity genes coracle, crumbs, and yurt. chem mutants dorsal open defects are similar to those present in yurt mutants, and, likewise, they have epithelial polarity defects. chem1 and chem3 mutations suppress yurt3, and chem3 mutants suppress crumbs1 mutations. In contrast, chem1 and coracle2 mutations enhance each other. Compared to controls, in chem mutants in embryonic lateral epithelia Crumbs expression is mislocalized and reduced, Coracle is increased and mislocalized basally at embryonic stages 13–14, then reduced at stage 16. Arm expression has a similar pattern but levels are reduced. PMID:27920954

  3. RNA editing in Drosophila melanogaster: new targets and functionalconsequences

    SciTech Connect

    Stapleton, Mark; Carlson, Joseph W.; Celniker, Susan E.

    2006-09-05

    Adenosine deaminases that act on RNA (ADARs) catalyze the site-specific conversion of adenosine to inosine in primary mRNA transcripts. These re-coding events affect coding potential, splice-sites, and stability of mature mRNAs. ADAR is an essential gene and studies in mouse, C. elegans, and Drosophila suggest its primary function is to modify adult behavior by altering signaling components in the nervous system. By comparing the sequence of isogenic cDNAs to genomic DNA, we have identified and experimentally verified 27 new targets of Drosophila ADAR. Our analyses lead us to identify new classes of genes whose transcripts are targets of ADAR including components of the actin cytoskeleton, and genes involved in ion homeostasis and signal transduction. Our results indicate that editing in Drosophila increases the diversity of the proteome, and does so in a manner that has direct functional consequences on protein function.

  4. RNA editing in Drosophila melanogaster: New targets and functional consequences

    PubMed Central

    Carlson, Joseph W.; Celniker, Susan E.

    2006-01-01

    Adenosine deaminases that act on RNA [adenosine deaminase, RNA specific (ADAR)] catalyze the site-specific conversion of adenosine to inosine in primary mRNA transcripts. These re-coding events affect coding potential, splice sites, and stability of mature mRNAs. ADAR is an essential gene, and studies in mouse, Caenorhabditis elegans, and Drosophila suggest that its primary function is to modify adult behavior by altering signaling components in the nervous system. By comparing the sequence of isogenic cDNAs to genomic DNA, we have identified and experimentally verified 27 new targets of Drosophila ADAR. Our analyses led us to identify new classes of genes whose transcripts are targets of ADAR, including components of the actin cytoskeleton and genes involved in ion homeostasis and signal transduction. Our results indicate that editing in Drosophila increases the diversity of the proteome, and does so in a manner that has direct functional consequences on protein function. PMID:17018572

  5. Mutations in durum wheat SBEII genes conferring increased amylose and resistant starch affect grain yield components, semolina and pasta quality and fermentation responses in rats

    USDA-ARS?s Scientific Manuscript database

    Increased amylose in wheat (Triticum spp.) starch is associated with increased resistant starch, a fermentable dietary fiber. Fermentation of resistant starch in the large intestine produces short-chain fatty acids that provide human health benefits. Since wheat foods are an important component of t...

  6. Flavin reduction activates Drosophila cryptochrome.

    PubMed

    Vaidya, Anand T; Top, Deniz; Manahan, Craig C; Tokuda, Joshua M; Zhang, Sheng; Pollack, Lois; Young, Michael W; Crane, Brian R

    2013-12-17

    Entrainment of circadian rhythms in higher organisms relies on light-sensing proteins that communicate to cellular oscillators composed of delayed transcriptional feedback loops. The principal photoreceptor of the fly circadian clock, Drosophila cryptochrome (dCRY), contains a C-terminal tail (CTT) helix that binds beside a FAD cofactor and is essential for light signaling. Light reduces the dCRY FAD to an anionic semiquinone (ASQ) radical and increases CTT proteolytic susceptibility but does not lead to CTT chemical modification. Additional changes in proteolytic sensitivity and small-angle X-ray scattering define a conformational response of the protein to light that centers at the CTT but also involves regions remote from the flavin center. Reduction of the flavin is kinetically coupled to CTT rearrangement. Chemical reduction to either the ASQ or the fully reduced hydroquinone state produces the same conformational response as does light. The oscillator protein Timeless (TIM) contains a sequence similar to the CTT; the corresponding peptide binds dCRY in light and protects the flavin from oxidation. However, TIM mutants therein still undergo dCRY-mediated degradation. Thus, photoreduction to the ASQ releases the dCRY CTT and promotes binding to at least one region of TIM. Flavin reduction by either light or cellular reductants may be a general mechanism of CRY activation.

  7. Flavin reduction activates Drosophila cryptochrome

    PubMed Central

    Vaidya, Anand T.; Top, Deniz; Manahan, Craig C.; Tokuda, Joshua M.; Zhang, Sheng; Pollack, Lois; Young, Michael W.; Crane, Brian R.

    2013-01-01

    Entrainment of circadian rhythms in higher organisms relies on light-sensing proteins that communicate to cellular oscillators composed of delayed transcriptional feedback loops. The principal photoreceptor of the fly circadian clock, Drosophila cryptochrome (dCRY), contains a C-terminal tail (CTT) helix that binds beside a FAD cofactor and is essential for light signaling. Light reduces the dCRY FAD to an anionic semiquinone (ASQ) radical and increases CTT proteolytic susceptibility but does not lead to CTT chemical modification. Additional changes in proteolytic sensitivity and small-angle X-ray scattering define a conformational response of the protein to light that centers at the CTT but also involves regions remote from the flavin center. Reduction of the flavin is kinetically coupled to CTT rearrangement. Chemical reduction to either the ASQ or the fully reduced hydroquinone state produces the same conformational response as does light. The oscillator protein Timeless (TIM) contains a sequence similar to the CTT; the corresponding peptide binds dCRY in light and protects the flavin from oxidation. However, TIM mutants therein still undergo dCRY-mediated degradation. Thus, photoreduction to the ASQ releases the dCRY CTT and promotes binding to at least one region of TIM. Flavin reduction by either light or cellular reductants may be a general mechanism of CRY activation. PMID:24297896

  8. PREFACE: The Irago Conference 2012

    NASA Astrophysics Data System (ADS)

    Sandhu, Adarsh; Okada, Hiroshi

    2013-04-01

    . Irago Conference 2013 is scheduled to be held in October 2013 as a platform for participants from a wide range of backgrounds and specialities to interact and discuss solutions to increasingly important environmental, social, and technological challenges people of the 21st century. Conference photograph

  9. Handling Alters Aggression and "Loser" Effect Formation in "Drosophila Melanogaster"

    ERIC Educational Resources Information Center

    Trannoy, Severine; Chowdhury, Budhaditya; Kravitz, Edward A.

    2015-01-01

    In "Drosophila," prior fighting experience influences the outcome of later contests: losing a fight increases the probability of losing second contests, thereby revealing "loser" effects that involve learning and memory. In these experiments, to generate and quantify the behavioral changes observed as consequences of losing…

  10. Trap designs for monitoring Drosophila suzukii (Diptera: Drosophilidae)

    USDA-ARS?s Scientific Manuscript database

    Drosophila suzukii Matsumura, an invasive pest of small and stone fruits, has been recently detected in 33 states of the U.S.A., and in Canada, Mexico, and Europe. This pest attacks ripening fruit causing economic losses including increased management costs and crop rejection. Ongoing research aim...

  11. Handling Alters Aggression and "Loser" Effect Formation in "Drosophila Melanogaster"

    ERIC Educational Resources Information Center

    Trannoy, Severine; Chowdhury, Budhaditya; Kravitz, Edward A.

    2015-01-01

    In "Drosophila," prior fighting experience influences the outcome of later contests: losing a fight increases the probability of losing second contests, thereby revealing "loser" effects that involve learning and memory. In these experiments, to generate and quantify the behavioral changes observed as consequences of losing…

  12. Monitoring Drosophila suzukii Matsumura in Oregon, USA sweet cherry orchards.

    USDA-ARS?s Scientific Manuscript database

    Drosophila suzukii rapidly became a significant cherry pest in the western United States after it was observed damaging cherries in 2009 in California. It has caused significant damage to ripening cherries in all major USA cherry production districts leading to increased management costs and reduced...

  13. The 2009 National Environmental Public Health Conference: one model for planning green and healthy conferences.

    PubMed

    Ruckart, Perri Zeitz; Moore, Cory; Burgin, Deborah; Byrne, Maggie Kelly

    2011-01-01

    The Centers for Disease Control and Prevention's National Center for Environmental Health and the Agency for Toxic Substances and Disease Registry committed to making their 2009 National Environmental Public Health Conference a model for green and healthy conferences. The conference included increased opportunities for physical activity, both as part of conference events and for transportation to the conference. In addition, conference meals were healthy and sustainably sourced. The conference also implemented intuitive, accessible recycling; online scheduling and evaluation to minimize hard-copy materials; and the purchase of carbon offsets to reduce the unwanted environmental impact of the conference. Public health professionals have an opportunity and obligation to support healthy behaviors at their events and to serve as leaders in this area. Facilitating healthy and sustainable choices is in alignment with goals for both public health and broader social issues-such as environmental quality-that have a direct bearing on public health.

  14. The 2009 National Environmental Public Health Conference: One Model for Planning Green and Healthy Conferences

    PubMed Central

    Ruckart, Perri Zeitz; Moore, Cory; Burgin, Deborah; Byrne, Maggie Kelly

    2011-01-01

    The Centers for Disease Control and Prevention's National Center for Environmental Health and the Agency for Toxic Substances and Disease Registry committed to making their 2009 National Environmental Public Health Conference a model for green and healthy conferences. The conference included increased opportunities for physical activity, both as part of conference events and for transportation to the conference. In addition, conference meals were healthy and sustainably sourced. The conference also implemented intuitive, accessible recycling; online scheduling and evaluation to minimize hard-copy materials; and the purchase of carbon offsets to reduce the unwanted environmental impact of the conference. Public health professionals have an opportunity and obligation to support healthy behaviors at their events and to serve as leaders in this area. Facilitating healthy and sustainable choices is in alignment with goals for both public health and broader social issues—such as environmental quality—that have a direct bearing on public health. PMID:21563713

  15. Increased pilus production conferred by a naturally occurring mutation alters host-pathogen interaction in favor of carriage in Streptococcus pyogenes.

    PubMed

    Flores, Anthony R; Olsen, Randall J; Cantu, Concepcion; Pallister, Kyler B; Guerra, Fermin E; Voyich, Jovanka M; Musser, James M

    2017-03-06

    Studies of the human pathogen group A Streptococcus (GAS) define the carrier phenotype as increased ability to adhere to and persist on epithelial surfaces and decreased ability to cause disease. We tested the hypothesis that a single amino acid change (Arg135Gly) in a highly conserved sensor kinase (LiaS) of a poorly defined GAS regulatory system contributes to a carrier phenotype through increased pilus production. When introduced into an emm serotype-matched invasive strain, the carrier allele (liaS(R135G)) recapitulated a carrier phenotype defined by increased ability to adhere to mucosal surfaces and decreased ability to cause disease. Gene transcript analyses revealed that the liaS mutation significantly altered transcription of the genes encoding pilus when in the presence of bacitracin. Elimination of pilus production in the isogenic carrier mutant decreased ability to colonize the mouse nasopharynx, adhere to and be internalized by cultured human epithelial cells, and restored a virulence phenotype in a mouse model of necrotizing fasciitis. We also observed significantly reduced survival of the isogenic carrier mutant compared to the parental invasive strain after exposure to human neutrophils. Elimination of pilus in the isogenic carrier mutant increased neutrophil survival to the parental invasive strain level. Together, our data demonstrate that the carrier mutation (liaS(R135G)) affects pilus expression. Our data suggest new mechanisms of pilus gene regulation in GAS and differs from the enhanced invasiveness associated with increased pilus production in other bacterial pathogens.

  16. Genome of Drosophila suzukii, the Spotted Wing Drosophila

    PubMed Central

    Chiu, Joanna C.; Jiang, Xuanting; Zhao, Li; Hamm, Christopher A.; Cridland, Julie M.; Saelao, Perot; Hamby, Kelly A.; Lee, Ernest K.; Kwok, Rosanna S.; Zhang, Guojie; Zalom, Frank G.; Walton, Vaughn M.; Begun, David J.

    2013-01-01

    Drosophila suzukii Matsumura (spotted wing drosophila) has recently become a serious pest of a wide variety of fruit crops in the United States as well as in Europe, leading to substantial yearly crop losses. To enable basic and applied research of this important pest, we sequenced the D. suzukii genome to obtain a high-quality reference sequence. Here, we discuss the basic properties of the genome and transcriptome and describe patterns of genome evolution in D. suzukii and its close relatives. Our analyses and genome annotations are presented in a web portal, SpottedWingFlyBase, to facilitate public access. PMID:24142924

  17. 10. international mouse genome conference

    SciTech Connect

    Meisler, M.H.

    1996-12-31

    Ten years after hosting the First International Mammalian Genome Conference in Paris in 1986, Dr. Jean-Louis Guenet presided over the Tenth Conference at the Pasteur Institute, October 7--10, 1996. The 1986 conference was a satellite to the Human Gene Mapping Workshop and had approximately 50 attendees. The 1996 meeting was attended by 300 scientists from around the world. In the interim, the number of mapped loci in the mouse increased from 1,000 to over 20,000. This report contains a listing of the program and its participants, and two articles that review the meeting and the role of the laboratory mouse in the Human Genome project. More than 200 papers were presented at the conference covering the following topics: International mouse chromosome committee meetings; Mutant generation and identification; Physical and genetic maps; New technology and resources; Chromatin structure and gene regulation; Rate and hamster genetic maps; Informatics and databases; and Quantitative trait analysis.

  18. Indy gene variation in natural populations confers fitness advantage and life span extension through transposon insertion.

    PubMed

    Zhu, Chen-Tseh; Chang, Chengyi; Reenan, Robert A; Helfand, Stephen L

    2014-01-01

    Natural selection acts to maximize reproductive fitness. However, antagonism between life span and reproductive success frequently poses a dilemma pitting the cost of fecundity against longevity. Here, we show that natural populations of Drosophila melanogaster harbor a Hoppel transposon insertion variant in the longevity gene Indy (I'm not dead yet), which confers both increased reproduction and longevity through metabolic changes. Heterozygosity for this natural long-lived variant has been maintained in isolates despite long-term inbreeding under laboratory conditions and advantageously confers increased fecundity. DNA sequences of variant chromosome isolates show evidence of selective sweep acting on the advantageous allele, suggesting that natural selection acts to maintain this variant. The transposon insertion also regulates Indy expression level, which has experimentally been shown to affect life span and fecundity. Thus, in the wild, evolution reaffirms that the mechanism of heterozygote advantage has acted upon the Indy gene to assure increased reproductive fitness and, coincidentally, longer life span through regulatory transposon mutagenesis.

  19. Invasive Drosophila suzukii facilitates Drosophila melanogaster infestation and sour rot outbreaks in the vineyards

    PubMed Central

    Guilhot, R.; Xuéreb, A.; Benoit, L.; Chapuis, M. P. ; Gibert, P.

    2017-01-01

    How do invasive pests affect interactions between members of pre-existing agrosystems? The invasive pest Drosophila suzukii is suspected to be involved in the aetiology of sour rot, a grapevine disease that otherwise develops following Drosophila melanogaster infestation of wounded berries. We combined field observations with laboratory assays to disentangle the relative roles of both Drosophila in disease development. We observed the emergence of numerous D. suzukii, but no D. melanogaster flies, from bunches that started showing mild sour rot symptoms days after field collection. However, bunches that already showed severe rot symptoms in the field mostly contained D. melanogaster. In the laboratory, oviposition by D. suzukii triggered sour rot development. An independent assay showed the disease increased grape attractiveness to ovipositing D. melanogaster females. Our results suggest that in invaded vineyards, D. suzukii facilitates D. melanogaster infestation and, consequently, favours sour rot outbreaks. Rather than competing with close species, the invader subsequently permits their reproduction in otherwise non-accessible resources and may cause more frequent, or more extensive, disease outbreaks. PMID:28405407

  20. Increased expression of bHLH Transcription Factor E2A (TCF3) in prostate cancer promotes proliferation and confers resistance to doxorubicin induced apoptosis

    PubMed Central

    Patel, Divya; Chaudhary, Jaideep

    2012-01-01

    E2A (TCF3) is a multifunctional basic helix loop helix (bHLH), transcription factor. E2A regulates transcription of target genes by homo- or heterodimerization with cell specific bHLH proteins. In general, E2A promotes cell differentiation, acts as a negative regulator of cell proliferation in normal cells and cancer cell lines and is required for normal B-cell development. Given the diverse biological pathways regulated/ influenced by E2A little is known about its expression in cancer. In this study we investigated the expression of E2A in prostate cancer. Unexpectedly, E2A immuno-histochemistry demonstrated increased E2A expression in prostate cancer as compared to normal prostate. Silencing of E2A in prostate cancer cells DU145 and PC3 led to a significant reduction in proliferation due to G1 arrest that was in part mediated by increased CDKN1A(p21) and decreased Id1, Id3 and c-myc. E2A silencing in prostate cancer cell lines also resulted in increased apoptosis due to increased mitochondrial permeability and caspase 3/7 activation. Moreover, silencing of E2A increased sensitivity to doxorubicin induced apoptosis. Based on our results, we propose that E2A could be an upstream regulator of Id1 and c-Myc which are highly expressed in prostate cancer. These results for the first time demonstrate that E2A could in fact acts as a tumor promoter at least in prostate cancer. PMID:22564737

  1. Conference Summary

    NASA Astrophysics Data System (ADS)

    Sanders, David B.

    2014-07-01

    This conference on ``Multi-wavelength AGN Surveys and Studies'' has provided a detailed look at the explosive growth over the past decade, of available astronomical data from a growing list of large scale sky surveys, from radio-to-gamma rays. We are entering an era were multi-epoch (months to weeks) surveys of the entire sky, and near-instantaneous follow-up observations of variable sources, are elevating time-domain astronomy to where it is becoming a major contributor to our understanding of Active Galactic Nuclei (AGN). While we can marvel at the range of extragalactic phenomena dispayed by sources discovered in the original ``Markarian Survey'' - the first large-scale objective prism survey of the Northern Sky carried out at the Byurakan Astronomical Observtory almost a half-century ago - it is clear from the talks and posters presented at this meeting that the data to be be obtained over the next decade will be needed if we are to finally understand which phase of galaxy evolution each Markarian Galaxy represents.

  2. Cytokinesis in Drosophila male meiosis

    PubMed Central

    Giansanti, Maria Grazia; Sechi, Stefano; Frappaolo, Anna; Belloni, Giorgio; Piergentili, Roberto

    2012-01-01

    Cytokinesis separates the cytoplasm and the duplicated genome into two daughter cells at the end of cell division. This process must be finely regulated to maintain ploidy and prevent tumor formation. Drosophila male meiosis provides an excellent cell system for investigating cytokinesis. Mutants affecting this process can be easily identified and spermatocytes are large cells particularly suitable for cytological analysis of cytokinetic structures. Over the past decade, the powerful tools of Drosophila genetics and the unique characteristics of this cell system have led researchers to identify molecular players of the cell cleavage machinery and to address important open questions. Although spermatocyte cytokinesis is incomplete, resulting in formation of stable intercellular bridges, the molecular mechanisms are largely conserved in somatic cells. Thus, studies of Drosophila male meiosis will shed new light on the complex cell circuits regulating furrow ingression and substantially further our knowledge of cancer and other human diseases. PMID:23094234

  3. Why Drosophila to Study Phototransduction?

    PubMed Central

    Pak, William L.

    2010-01-01

    This review recounts the early history of Drosophila phototransduction genetics, covering the period between approximately 1966 to 1979. Early in this period, the author felt that there was an urgent need for a new approach in phototransduction research. Through inputs from a number of colleagues, he was led to consider isolating Drosophila mutants that are defective in the electroretinogram. Thanks to the efforts of dedicated associates and technical staff, by the end of this period, he was able to accumulate a large number of such mutants. Particularly important in this effort was the use of the mutant assay protocol based on the “prolonged depolarizing afterpotential.” This collection of mutants formed the basis of the subsequent intensive investigations of the Drosophila phototransduction cascade by many investigators. PMID:20536286

  4. Micromechanics of Drosophila Audition

    NASA Astrophysics Data System (ADS)

    Göpfert, M. C.; Robert, D.

    2003-02-01

    An analysis is presented of the auditory micromechanics of the fruit fly Drosophila melanogaster. In this animal, the distal part of the antenna constitutes a resonantly tuned sound receiver, the vibrations of which are transduced by a chordotonal sense organ in the antenna's base. Analyzing the mechanical behavior of the antennal receiver by means of microscanning laser Doppler vibrometry, we show that the auditory system of wild-type flies exhibits a hardening stiffness nonlinearity and spontaneously generates oscillations in the absence of external stimuli. According to the deprivation of these mechanical properties in mechanosensory mutants, the receiver's nonlinearity and oscillation activity are introduced by chordotonal auditory neurons. Requiring the mechanoreceptor-specific extracellular linker protein No-mechanoreceptor-potential-A (NompA), NompC mechanosensory transduction channels, Beethoven (Btv), and Touch-insensitive-larva-B (TilB), nonlinearity and oscillation activity of the fly's antennal receiver depend on prominent components of the auditory transduction machinery and seem to originate from motility of auditory receptor cilia.

  5. Modelling the Drosophila embryo.

    PubMed

    Jaeger, Johannes

    2009-12-01

    I provide a historical overview on the use of mathematical models to gain insight into pattern formation during early development of the fruit fly Drosophila melanogaster. It is my intention to illustrate how the aims and methodology of modelling have changed from the early beginnings of a theoretical developmental biology in the 1960s to modern-day systems biology. I show that even early modelling attempts addressed interesting and relevant questions, which were not tractable by experimental approaches. Unfortunately, their validation was severely hampered by a lack of specificity and appropriate experimental evidence. There is a simple lesson to be learned from this: we cannot deduce general rules for pattern formation from first principles or spurious reproduction of developmental phenomena. Instead, we must infer such rules (if any) from detailed and accurate studies of specific developmental systems. To achieve this, mathematical modelling must be closely integrated with experimental approaches. I report on progress that has been made in this direction in the past few years and illustrate the kind of novel insights that can be gained from such combined approaches. These insights demonstrate the great potential (and some pitfalls) of an integrative, systems-level investigation of pattern formation.

  6. Expression of uroporphyrinogen decarboxylase or coproporphyrinogen oxidase antisense RNA in tobacco induces pathogen defense responses conferring increased resistance to tobacco mosaic virus.

    PubMed

    Mock, H P; Heller, W; Molina, A; Neubohn, B; Sandermann, H; Grimm, B

    1999-02-12

    Transgenic tobacco plants with reduced activity of either uroporphyrinogen decarboxylase or coproporphyrinogen oxidase, two enzymes of the tetrapyrrole biosynthetic pathway, are characterized by the accumulation of photosensitizing tetrapyrrole intermediates, antioxidative responses, and necrotic leaf lesions. In this study we report on cellular responses in uroporphyrinogen decarboxylase and coproporphyrinogen oxidase antisense plants, normally associated with pathogen defense. These plants accumulate the highly fluorescent coumarin scopolin in their leaves. They also display increased pathogenesis-related protein expression and higher levels of free and conjugated salicylic acid. Upon tobacco mosaic virus inoculation, the plants with leaf lesions and high levels of PR-1 mRNA expression show reduced accumulation of virus RNA relative to wild-type controls. This result is indicative of an increased resistance to tobacco mosaic virus. We conclude that porphyrinogenesis as a result of deregulated tetrapyrrole synthesis induces a set of defense responses that resemble the hypersensitive reaction observed after pathogen attack.

  7. Light induced increases of photoreceptor layer reflectance in response to rhodopsin bleaching in mice measured in vivo with optical coherence tomography (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Zhang, Pengfei; Goswami, Mayank; Pugh, Edward N.; Zawadzki, Robert J.

    2017-02-01

    We have recently reported observations of light-induced broadband fundus reflectance changes in two most commonly used strains of laboratory mice, C57Bl/6J (pigmented) and Balb/c (un- pigmented albino). The action spectrum of the reflectance increase corresponded to the absorption spectrum of mouse rhodopsin in situ. Spectral changes in mouse fundus reflectivity were calculated from measurements made by broadband spectrometer, interfaced with our mouse retinal SLO system, obtained before and after bleaching. This results were fitted with a model of mouse fundus reflectance, quantifying contributions from loss of rhodopsin absorption with bleaching, absorption by oxygenated hemoglobin (HbO2) in the choroid (Balb/c), and absorption by melanin (C57Bl/6J) additionally both mouse strains exhibited light-induced broadband reflectance changes explained as bleaching-induced reflectivity increases at photoreceptor inner segment/outer segment (IS/OS) junctions and OS tips. Here we present results investigating the kinetics of the increases in reflectivity with Optical Coherence Tomography operating in a 780-950 nm band.

  8. Sleep restores behavioral plasticity to Drosophila mutants.

    PubMed

    Dissel, Stephane; Angadi, Veena; Kirszenblat, Leonie; Suzuki, Yasuko; Donlea, Jeff; Klose, Markus; Koch, Zachary; English, Denis; Winsky-Sommerer, Raphaelle; van Swinderen, Bruno; Shaw, Paul J

    2015-05-18

    Given the role that sleep plays in modulating plasticity, we hypothesized that increasing sleep would restore memory to canonical memory mutants without specifically rescuing the causal molecular lesion. Sleep was increased using three independent strategies: activating the dorsal fan-shaped body, increasing the expression of Fatty acid binding protein (dFabp), or by administering the GABA-A agonist 4,5,6,7-tetrahydroisoxazolo-[5,4-c]pyridine-3-ol (THIP). Short-term memory (STM) or long-term memory (LTM) was evaluated in rutabaga (rut) and dunce (dnc) mutants using aversive phototaxic suppression and courtship conditioning. Each of the three independent strategies increased sleep and restored memory to rut and dnc mutants. Importantly, inducing sleep also reverses memory defects in a Drosophila model of Alzheimer's disease. Together, these data demonstrate that sleep plays a more fundamental role in modulating behavioral plasticity than previously appreciated and suggest that increasing sleep may benefit patients with certain neurological disorders.

  9. The effect of Emblica officinalis diet on lifespan, sexual behavior, and fitness characters in Drosophila melanogaster.

    PubMed

    Pathak, Pankaj; Prasad, B R Guru; Murthy, N Anjaneya; Hegde, S N

    2011-04-01

    Drosophila is an excellent organism to test Ayurvedic medicines. The objective of our study was to explore the potential of Emblica officinalis drug on longevity, sexual behavior, and reproductive fitness of Drosophila melanogaster using adult feeding method. Increase in the lifespan, fecundity, fertility, ovarioles number, and developmental time was observed in both parents and F1 generation, but not in the F2 generation in experimental culture (control + E. officinalis). According to the Duncan's multiple range test and ANOVA, there is a significant difference between two cultures. It was also noticed that E. officinalis influence some fitness characters in Drosophila along with sexual behavior.

  10. Increased expression of bHLH transcription factor E2A (TCF3) in prostate cancer promotes proliferation and confers resistance to doxorubicin induced apoptosis

    SciTech Connect

    Patel, Divya; Chaudhary, Jaideep

    2012-05-25

    Highlights: Black-Right-Pointing-Pointer E2A, considered as a tumor suppressor is highly expressed in prostate cancer. Black-Right-Pointing-Pointer Silencing of E2A attenuates cell proliferation and promotes apoptosis. Black-Right-Pointing-Pointer E2A regulates c-myc, Id1, Id3 and CDKN1A expression. Black-Right-Pointing-Pointer Loss of E2A promotes doxorubicin dependent apoptosis in prostate cancer cells. Black-Right-Pointing-Pointer Results suggest that E2A acts as a tumor promoter at least in prostate cancer. -- Abstract: E2A (TCF3) is a multifunctional basic helix loop helix (bHLH), transcription factor. E2A regulates transcription of target genes by homo- or heterodimerization with cell specific bHLH proteins. In general, E2A promotes cell differentiation, acts as a negative regulator of cell proliferation in normal cells and cancer cell lines and is required for normal B-cell development. Given the diverse biological pathways regulated/influenced by E2A little is known about its expression in cancer. In this study we investigated the expression of E2A in prostate cancer. Unexpectedly, E2A immuno-histochemistry demonstrated increased E2A expression in prostate cancer as compared to normal prostate. Silencing of E2A in prostate cancer cells DU145 and PC3 led to a significant reduction in proliferation due to G1 arrest that was in part mediated by increased CDKN1A(p21) and decreased Id1, Id3 and c-myc. E2A silencing in prostate cancer cell lines also resulted in increased apoptosis due to increased mitochondrial permeability and caspase 3/7 activation. Moreover, silencing of E2A increased sensitivity to doxorubicin induced apoptosis. Based on our results, we propose that E2A could be an upstream regulator of Id1 and c-Myc which are highly expressed in prostate cancer. These results for the first time demonstrate that E2A could in fact acts as a tumor promoter at least in prostate cancer.

  11. Transcriptional responses in a Drosophila defensive symbiosis.

    PubMed

    Hamilton, Phineas T; Leong, Jong S; Koop, Ben F; Perlman, Steve J

    2014-03-01

    Inherited symbionts are ubiquitous in insects and can have important consequences for the fitness of their hosts. Many inherited symbionts defend their hosts against parasites or other natural enemies; however, the means by which most symbionts confer protection is virtually unknown. We examine the mechanisms of defence in a recently discovered case of symbiont-mediated protection, where the bacterial symbiont Spiroplasma defends the fly Drosophila neotestacea from a virulent nematode parasite, Howardula aoronymphium. Using quantitative PCR of Spiroplasma infection intensities and whole transcriptome sequencing, we attempt to distinguish between the following modes of defence: symbiont-parasite competition, host immune priming and the production of toxic factors by Spiroplasma. Our findings do not support a model of exploitative competition between Howardula and Spiroplasma to mediate defence, nor do we find strong support for host immune priming during Spiroplasma infection. Interestingly, we recovered sequence for putative toxins encoded by Spiroplasma, including a novel putative ribosome-inactivating protein, transcripts of which are up-regulated in response to nematode exposure. Protection via the production of toxins may be a widely used and important mechanism in heritable defensive symbioses in insects.

  12. Identification and characterization of Drosophila melanogaster paramyosin.

    PubMed

    Vinós, J; Domingo, A; Marco, R; Cervera, M

    1991-08-05

    Paramyosin, a major structural component of thick filaments in invertebrates has been isolated, purified and characterized from whole adult Drosophila melanogaster extracts and a specific polyclonal antibody against it has been prepared. Paramyosin has been identified on the basis of several criteria, including molecular weight, alpha-helicity, species distribution, capability of fiber formation in vitro and sequence. We have used the immunopurified polyclonal antibody to isolate eight clones from a lambda gt11 expression library of Drosophila 1 to 22 h embryo cDNA. The largest clone (pJV9) has been sequenced and encodes the coiled-coil region of D. melanogaster paramyosin that is 47% identical to Caenorhabditis elegans paramyosin. Indirect immunofluorescence in semi-thin sections of adult flies show fluorescence mainly in tubular muscle. Freshly prepared tubular myofibrils decorated with the immunoabsorbed antibody show the A region in the sarcomere as the specific localization of paramyosin. The amount of paramyosin in tubular synchronous muscles of insects appears to be five times higher than in fibrillar insect muscles. There are at least three paramyosin isoforms as shown by isoelectrofocusing separation. The more acidic and less abundant form is phosphorylated as shown by 32P in vivo labeling experiments in adult flies. The developmental pattern of expression of Drosophila paramyosin is presented. This mesoderm-specific protein, immunologically undetectable during gastrulation and early phases of germ band formation, progressively increases during organogenesis to the adult stage. Interestingly, it is also expressed as a major maternal product in the insoluble cytoskeletal fraction of the mature oocyte.

  13. Indy Mutations and Drosophila Longevity

    PubMed Central

    Rogina, Blanka; Helfand, Stephen L.

    2013-01-01

    Decreased expression of the fly and worm Indy genes extends longevity. The fly Indy gene and its mammalian homolog are transporters of Krebs cycle intermediates, with the highest rate of uptake for citrate. Cytosolic citrate has a role in energy regulation by affecting fatty acid synthesis and glycolysis. Fly, worm, and mice Indy gene homologs are predominantly expressed in places important for intermediary metabolism. Consequently, decreased expression of Indy in fly and worm, and the removal of mIndy in mice exhibit changes associated with calorie restriction, such as decreased levels of lipids, changes in carbohydrate metabolism and increased mitochondrial biogenesis. Here we report that several Indy alleles in a diverse array of genetic backgrounds confer increased longevity. PMID:23580130

  14. IL-10 enhances the phenotype of M2 macrophages induced by IL-4 and confers the ability to increase eosinophil migration.

    PubMed

    Makita, Naoyuki; Hizukuri, Yoshiyuki; Yamashiro, Kyoko; Murakawa, Masao; Hayashi, Yasuhiro

    2015-03-01

    M2 macrophages have been subdivided into subtypes such as IL-4-induced M2a and IL-10-induced M2c in vitro. Although it was reported that IL-10 stimulation leads to an increase in IL-4Rα, the effect of IL-4 and IL-10 in combination with macrophage subtype differentiation remains unclear. Thus, we sought to clarify whether IL-10 enhanced the M2 phenotype induced by IL-4. In this study, we showed that IL-10 enhanced IL-4Rα expression in M-CSF-induced bone marrow-derived macrophages (BMDMs). Global gene expression analysis of M2 macrophages induced by IL-4, IL-10 or IL-4 + IL-10 showed that IL-10 enhanced gene expression of M2a markers induced by IL-4 in M-CSF-induced BMDMs. Moreover, IL-4 and IL-10 synergistically induced CCL24 (Eotaxin-2) production. Enhanced CCL24 expression was also observed in GM-CSF-induced BMDMs and zymosan-elicited, thioglycolate-elicited and naive peritoneal macrophages. CCL24 is a CCR3 agonist and an eosinophil chemoattractant. In vitro, IL-4 + IL-10-stimulated macrophages produced a large amount of CCL24 and increased eosinophil migration, which was inhibited by anti-CCL24 antibody. We also showed that IL-4 + IL-10-stimulated (but not IL-4 or IL-10 alone) macrophages transferred into the peritoneum of C57BL/6J mice increased eosinophil infiltration into the peritoneal cavity. These results demonstrate that IL-4 + IL-10-simulated macrophages have enhanced M2a macrophage-related gene expression, CCL24 production and eosinophil infiltration-inducing activity, thereby suggesting their contribution to eosinophil-related diseases.

  15. 2004 Mutagenesis Gordon Conference

    SciTech Connect

    Dr. Sue Jinks-Robertson

    2005-09-16

    Mutations are genetic alterations that drive biological evolution and cause many, if not all, human diseases. Mutation originates via two distinct mechanisms: ''vertical'' variation is de novo change of one or few bases, whereas ''horizontal'' variation occurs by genetic recombination, which creates new mosaics of pre-existing sequences. The Mutagenesis Conference has traditionally focused on the generation of mutagenic intermediates during normal DNA synthesis or in response to environmental insults, as well as the diverse repair mechanisms that prevent the fixation of such intermediates as permanent mutations. While the 2004 Conference will continue to focus on the molecular mechanisms of mutagenesis, there will be increased emphasis on the biological consequences of mutations, both in terms of evolutionary processes and in terms of human disease. The meeting will open with two historical accounts of mutation research that recapitulate the intellectual framework of this field and thereby place the current research paradigms into perspective. The two introductory keynote lectures will be followed by sessions on: (1) mutagenic systems, (2) hypermutable sequences, (3) mechanisms of mutation, (4) mutation avoidance systems, (5) mutation in human hereditary and infectious diseases, (6) mutation rates in evolution and genotype-phenotype relationships, (7) ecology, mutagenesis and the modeling of evolution and (8) genetic diversity of the human population and models for human mutagenesis. The Conference will end with a synthesis of the meeting as the keynote closing lecture.

  16. Chemically induced expression of rice OSB2 under the control of the OsPR1.1 promoter confers increased anthocyanin accumulation in transgenic rice.

    PubMed

    Kawahigashi, Hiroyuki; Hirose, Sakiko; Iwai, Takayoshi; Ohashi, Yuko; Sakamoto, Wataru; Maekawa, Masahiko; Ohkawa, Yasunobu

    2007-02-21

    Anthocyanin pigmentation provides an excellent system with which to study the regulation of gene expression in higher plants. In this study, OsPR1.1 promoter was isolated and the promoter activity was monitored using a reporter gene OSB2, which encodes a transcription factor for anthocyanin synthesis in rice plants. We introduced PR::OSB2 plasmid into an isogenic Taichung 65, no. 99-962 T-65 CBA B9F5 (T65 CBA), rice line (Oryza sativa L.) and found that the transgenic rice plants exhibited anthocyanin accumulation by the induced expression of OSB2 after chemical treatments with methyl jasmonate (MeJA) and 2,6-dichloroisonicotinic acid (DCINA). The shoots of the PR::OSB2 transgenic rice plants changed color to red after application of the chemicals accompanying with the increased anthocyanin content to approximately 5-fold by MeJA and 2-fold by DCINA, respectively. The anthocyanin accumulation was consistent with the increase of the expression of OSB2 and anthocyanidin synthase (ANS). This color change system could provide a useful and easy way to produce transgenic plants for monitoring of chemicals in the environment.

  17. Conference Scene

    PubMed Central

    Leeder, J Steven; Lantos, John; Spielberg, Stephen P

    2015-01-01

    A major challenge for clinicians, pharmaceutical companies and regulatory agencies is to better understand the relative contributions of ontogeny and genetic variation to observed variability in drug disposition and response across the pediatric age spectrum from preterm and term newborns, to infants, children and adolescents. Extrapolation of adult experience with pharmacogenomics and personalized medicine to pediatric patients of different ages and developmental stages, is fraught with many challenges. Compared with adults, pediatric pharmacogenetics and pharmacogenomics involves an added measure of complexity as variability owing to developmental processes, or ontogeny, is superimposed upon genetic variation. Furthermore, some pediatric diseases have no adult correlate or are more prevalent in children compared with adults, and several adverse drug reactions are unique to children, or occur at a higher frequency in children. The primary objective of this conference was to initiate an ongoing series of annual meetings on ‘Pediatric Pharmacogenomics and Personalized Medicine’ organized by the Center for Personalized Medicine and Therapeutic Innovation and Division of Clinical Pharmacology and Medical Therapeutics at Children’s Mercy Hospitals and Clinics in Kansas City, MO, USA. The primary goals of the inaugural meeting were: to bring together clinicians, basic and translational scientists and allied healthcare practitioners, and engage in a multi- and cross-disciplinary dialog aimed at implementing personalized medicine in pediatric settings; to provide a forum for the presentation and the dissemination of research related to the application of pharmacogenomic strategies to investigations of variability of drug disposition and response in children; to explore the ethical, legal and societal implications of pharmacogenomics and personalized medicine that are unique to children; and finally, to create networking opportunities for stimulating discussion

  18. The F130S point mutation in the Arabidopsis high-affinity K+ transporter AtHAK5 increases K+ over Na+ and Cs+ selectivity and confers Na+ and Cs+ tolerance to yeast under heterologous expression

    PubMed Central

    Alemán, Fernando; Caballero, Fernando; Ródenas, Reyes; Rivero, Rosa M.; Martínez, Vicente; Rubio, Francisco

    2014-01-01

    Potassium (K+) is an essential macronutrient required for plant growth, development and high yield production of crops. Members of group I of the KT/HAK/KUP family of transporters, such as HAK5, are key components for K+ acquisition by plant roots at low external K+ concentrations. Certain abiotic stress conditions such as salinity or Cs+-polluted soils may jeopardize plant K+ nutrition because HAK5-mediated K+ transport is inhibited by Na+ and Cs+. Here, by screening in yeast a randomly-mutated collection of AtHAK5 transporters, a new mutation in AtHAK5 sequence is identified that greatly increases Na+ tolerance. The single point mutation F130S, affecting an amino acid residue conserved in HAK5 transporters from several species, confers high salt tolerance, as well as Cs+ tolerance. This mutation increases more than 100-fold the affinity of AtHAK5 for K+ and reduces the Ki values for Na+ and Cs+, suggesting that the F130 residue may contribute to the structure of the pore region involved in K+ binding. In addition, this mutation increases the Vmax for K+. All this changes occur without increasing the amount of the AtHAK5 protein in yeast and support the idea that this residue is contributing to shape the selectivity filter of the AtHAK5 transporter. PMID:25228905

  19. Conference report: 12th Annual University of Wisconsin Land O'Lakes Bioanalytical Conference.

    PubMed

    DeMuth, James E; Briscoe, Chad; Amaravadi, Lakshmi; Arnold, Mark E; Clement, Robert P; Fluhler, Eric N; Ji, Qin C; Stubbs, R John

    2011-10-01

    This University of Wisconsin School of Pharmacy bioanalytical conference is presented each year by the Extension Services in Pharmacy, the professional development department within the school. The purpose of this 4-day conference is to provide an educational forum to discuss issues and applications associated with the analysis of xenobiotics, metabolites, biologics and biomarkers in biological matrices. The conference is designed to include and encourage an open exchange of scientific and methodological applications for bioanalysis. To increase the interactive nature of the conference, the program was a mixture of lectures, poster sessions, round table discussions and workshops. This article summarizes the presentations at the 12th Annual Conference.

  20. The assembly of metals chelation by thiols and vacuolar compartmentalization conferred increased tolerance to and accumulation of cadmium and arsenic in transgenic Arabidopsis thaliana.

    PubMed

    Guo, Jiangbo; Xu, Wenzhong; Ma, Mi

    2012-01-15

    Transgenic Arabidopsis thaliana were developed to increase tolerance for and accumulation of heavy metals and metalloids by simultaneous overexpression of AsPCS1 and YCF1 (derived from garlic and baker's yeast) based on the fact that chelation of metals and vacuolar compartmentalization are the main strategies for heavy metals/metalloids detoxification and tolerance in plants. Dual-gene transgenic lines had the longest roots and the highest accumulation of Cd and As than single-gene transgenic lines and wildtype. When grown on cadmium or arsenic (arsenite/arsenate), Dual-gene transgenic lines accumulated over 2-10 folds cadmium/arsenite and 2-3 folds arsenate than wild type or plants expressing AsPCS1 or YCF1 alone. Such stacking modified genes involved in chelation of toxic metals and vacuolar compartmentalization represents a highly promising new tool for use in phytoremediation efforts. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Increased biomass, seed yield and stress tolerance is conferred in Arabidopsis by a novel enzyme from the resurrection grass Sporobolus stapfianus that glycosylates the strigolactone analogue GR24.

    PubMed

    Islam, Sharmin; Griffiths, Cara A; Blomstedt, Cecilia K; Le, Tuan-Ngoc; Gaff, Donald F; Hamill, John D; Neale, Alan D

    2013-01-01

    Isolation of gene transcripts from desiccated leaf tissues of the resurrection grass, Sporobolus stapfianus, resulted in the identification of a gene, SDG8i, encoding a Group 1 glycosyltransferase (UGT). Here, we examine the effects of introducing this gene, under control of the CaMV35S promoter, into the model plant Arabidopsis thaliana. Results show that Arabidopsis plants constitutively over-expressing SDG8i exhibit enhanced growth, reduced senescence, cold tolerance and a substantial improvement in protoplasmic drought tolerance. We hypothesise that expression of SDG8i in Arabidopsis negatively affects the bioactivity of metabolite/s that mediate/s environmentally-induced repression of cell division and expansion, both during normal development and in response to stress. The phenotype of transgenic plants over-expressing SDG8i suggests modulation in activities of both growth- and stress-related hormones. Plants overexpressing the UGT show evidence of elevated auxin levels, with the enzyme acting downstream of ABA to reduce drought-induced senescence. Analysis of the in vitro activity of the UGT recombinant protein product demonstrates that SDG8i can glycosylate the synthetic strigolactone analogue GR24, evoking a link with strigolactone-related processes in vivo. The large improvements observed in survival of transgenic Arabidopsis plants under cold-, salt- and drought-stress, as well as the substantial increases in growth rate and seed yield under non-stress conditions, indicates that overexpression of SDG8i in crop plants may provide a novel means of increasing plant productivity.

  2. Increased Biomass, Seed Yield and Stress Tolerance Is Conferred in Arabidopsis by a Novel Enzyme from the Resurrection Grass Sporobolus stapfianus That Glycosylates the Strigolactone Analogue GR24

    PubMed Central

    Islam, Sharmin; Griffiths, Cara A.; Blomstedt, Cecilia K.; Le, Tuan-Ngoc; Gaff, Donald F.; Hamill, John D.; Neale, Alan D.

    2013-01-01

    Isolation of gene transcripts from desiccated leaf tissues of the resurrection grass, Sporobolus stapfianus, resulted in the identification of a gene, SDG8i, encoding a Group 1 glycosyltransferase (UGT). Here, we examine the effects of introducing this gene, under control of the CaMV35S promoter, into the model plant Arabidopsis thaliana. Results show that Arabidopsis plants constitutively over-expressing SDG8i exhibit enhanced growth, reduced senescence, cold tolerance and a substantial improvement in protoplasmic drought tolerance. We hypothesise that expression of SDG8i in Arabidopsis negatively affects the bioactivity of metabolite/s that mediate/s environmentally-induced repression of cell division and expansion, both during normal development and in response to stress. The phenotype of transgenic plants over-expressing SDG8i suggests modulation in activities of both growth- and stress-related hormones. Plants overexpressing the UGT show evidence of elevated auxin levels, with the enzyme acting downstream of ABA to reduce drought-induced senescence. Analysis of the in vitro activity of the UGT recombinant protein product demonstrates that SDG8i can glycosylate the synthetic strigolactone analogue GR24, evoking a link with strigolactone-related processes in vivo. The large improvements observed in survival of transgenic Arabidopsis plants under cold-, salt- and drought-stress, as well as the substantial increases in growth rate and seed yield under non-stress conditions, indicates that overexpression of SDG8i in crop plants may provide a novel means of increasing plant productivity. PMID:24224034

  3. Gene-environment interactions in the causation of neural tube defects: folate deficiency increases susceptibility conferred by loss of Pax3 function.

    PubMed

    Burren, Katie A; Savery, Dawn; Massa, Valentina; Kok, Robert M; Scott, John M; Blom, Henk J; Copp, Andrew J; Greene, Nicholas D E

    2008-12-01

    Risk of neural tube defects (NTDs) is determined by genetic and environmental factors, among which folate status appears to play a key role. However, the precise nature of the link between low folate status and NTDs is poorly understood, and it remains unclear how folic acid prevents NTDs. We investigated the effect of folate level on risk of NTDs in splotch (Sp(2)(H)) mice, which carry a mutation in Pax3. Dietary folate restriction results in reduced maternal blood folate, elevated plasma homocysteine and reduced embryonic folate content. Folate deficiency does not cause NTDs in wild-type mice, but causes a significant increase in cranial NTDs among Sp(2)(H) embryos, demonstrating a gene-environment interaction. Control treatments, in which intermediate levels of folate are supplied, suggest that NTD risk is related to embryonic folate concentration, not maternal blood folate concentration. Notably, the effect of folate deficiency appears more deleterious in female embryos than males, since defects are not prevented by exogenous folic acid. Folate-deficient embryos exhibit developmental delay and growth retardation. However, folate content normalized to protein content is appropriate for developmental stage, suggesting that folate availability places a tight limit on growth and development. Folate-deficient embryos also exhibit a reduced ratio of s-adenosylmethionine (SAM) to s-adenosylhomocysteine (SAH). This could indicate inhibition of the methylation cycle, but we did not detect any diminution in global DNA methylation, in contrast to embryos in which the methylation cycle was specifically inhibited. Hence, folate deficiency increases the risk of NTDs in genetically predisposed splotch embryos, probably via embryonic growth retardation.

  4. Exposure to low UVA doses increases KatA and KatB catalase activities, and confers cross-protection against subsequent oxidative injuries in Pseudomonas aeruginosa.

    PubMed

    Pezzoni, Magdalena; Tribelli, Paula M; Pizarro, Ramón A; López, Nancy I; Costa, Cristina S

    2016-05-01

    Solar UVA radiation is one of the main environmental stress factors for Pseudomonas aeruginosa. Exposure to high UVA doses produces lethal effects by the action of the reactive oxygen species (ROS) it generates. P. aeruginosa has several enzymes, including KatA and KatB catalases, which provide detoxification of ROS. We have previously demonstrated that KatA is essential in defending P. aeruginosa against high UVA doses. In order to analyse the mechanisms involved in the adaptation of this micro-organism to UVA, we investigated the effect of exposure to low UVA doses on KatA and KatB activities, and the physiological consequences. Exposure to UVA induced total catalase activity; assays with non-denaturing polyacrylamide gels showed that both KatA and KatB activities were increased by radiation. This regulation occurred at the transcriptional level and depended, at least partly, on the increase in H2O2 levels. We demonstrated that exposure to low UVA produced a protective effect against subsequent lethal doses of UVA, sodium hypochlorite and H2O2. Protection against lethal UVA depends on katA, whilst protection against sodium hypochlorite depends on katB, demonstrating that different mechanisms are involved in the defence against these oxidative agents, although both genes can be involved in the global cellular response. Conversely, protection against lethal doses of H2O2 could depend on induction of both genes and/or (an)other defensive factor(s). A better understanding of the adaptive response of P. aeruginosa to UVA is relevant from an ecological standpoint and for improving disinfection strategies that employ UVA or solar irradiation.

  5. A dynamic deep sleep stage in Drosophila

    PubMed Central

    van Alphen, Bart; Yap, Melvyn H.W.; Kirszenblat, Leonie; Kottler, Benjamin; van Swinderen, Bruno

    2013-01-01

    How might one determine whether simple animals such as flies sleep in stages? Sleep in mammals is a dynamic process involving different stages of sleep intensity, and these are typically associated with measurable changes in brain activity (Blake and Gerard, 1937; Rechtschaffen and Kales, 1968; Webb and Agnew, 1971). Evidence for different sleep stages in invertebrates remains elusive, even though it has been well established that many invertebrate species require sleep (Campbell and Tobler, 1984; Hendricks et al., 2000; Shaw et al., 2000; Sauer et al., 2003). Here we use electrophysiology and arousal-testing paradigms to show that the fruit fly, Drosophila melanogaster, transitions between deeper and lighter sleep within extended bouts of inactivity, with deeper sleep intensities after ~15 and ~30 minutes of inactivity. As in mammals, the timing and intensity of these dynamic sleep processes in flies is homeostatically regulated and modulated by behavioral experience. Two molecules linked to synaptic plasticity regulate the intensity of the first deep sleep stage. Optogenetic upregulation of cyclic adenosine monophosphate (cAMP) during the day increases sleep intensity at night, whereas loss of function of a molecule involved in synaptic pruning, the fragile-X mental retardation protein (FMRP), increases sleep intensity during the day. Our results show that sleep is not homogenous in insects, and suggest that waking behavior and associated synaptic plasticity mechanisms determine the timing and intensity of deep sleep stages in Drosophila. PMID:23595750

  6. Circadian Rhythms and Sleep in Drosophila melanogaster.

    PubMed

    Dubowy, Christine; Sehgal, Amita

    2017-04-01

    for identifying a large set of genes, molecules, and neuroanatomic loci important for regulating sleep amount. Conserved aspects of sleep regulation in flies and mammals include wake-promoting roles for catecholamine neurotransmitters and involvement of hypothalamus-like regions, although other neuroanatomic regions implicated in sleep in flies have less clear parallels. Sleep is also subject to regulation by factors such as food availability, stress, and social environment. We are beginning to understand how the identified molecules and neurons interact with each other, and with the environment, to regulate sleep. Drosophila researchers can also take advantage of increasing mechanistic understanding of other behaviors, such as learning and memory, courtship, and aggression, to understand how sleep loss impacts these behaviors. Flies thus remain a valuable tool for both discovery of novel molecules and deep mechanistic understanding of sleep and circadian rhythms.

  7. Increasing Understanding of Public Problems and Policies: 1993. [Proceedings of the Annual Conference of the National Public Policy Education Committee (43rd, Clearwater Beach, Florida, September 12-15, 1993).

    ERIC Educational Resources Information Center

    Halbrook, Steve A., Ed.; Grace, Teddee E., Ed.

    The annual conference of the National Public Policy Education Committee (NPPEC) is held to improve the policy education efforts of extension workers responsible for public affairs programs. This publication contains 26 conference papers: "Rural America and the Information Revolution: An Exploration of Possibilities and Potentialities"…

  8. Home-School Alliances: Approaches to Increasing Parent Involvement in Children's Learning in Upper Elementary and Junior High Schools (Grades 4-9). Proceedings of the NIE Conference on Home-School Alliances (Washington, DC, October 5-7, 1980).

    ERIC Educational Resources Information Center

    Safran, Daniel, Ed.

    This report is a transcript of presentations from the 1980 Conference on Home-School Alliances, defined as specific coordination strategies between home and school, and developed to further the social and academic development of children and youths. Following the preface, brief overview of the purpose and nature of the conference, and the…

  9. Simultaneous Over-Expression of PaSOD and RaAPX in Transgenic Arabidopsis thaliana Confers Cold Stress Tolerance through Increase in Vascular Lignifications

    PubMed Central

    Shafi, Amrina; Dogra, Vivek; Gill, Tejpal; Ahuja, Paramvir Singh; Sreenivasulu, Yelam

    2014-01-01

    Antioxidant enzymes play a significant role in eliminating toxic levels of reactive oxygen species (ROS), generated during stress from living cells. In the present study, two different antioxidant enzymes namely copper-zinc superoxide dismutase derived from Potentilla astrisanguinea (PaSOD) and ascorbate peroxidase (RaAPX) from Rheum austral both of which are high altitude cold niche area plants of Himalaya were cloned and simultaneously over-expressed in Arabidopsis thaliana to alleviate cold stress. It was found that the transgenic plants over-expressing both the genes were more tolerant to cold stress than either of the single gene expressing transgenic plants during growth and development. In both single (PaSOD, RaAPX) and double (PaSOD + RaAPX) transgenic plants higher levels of total antioxidant enzyme activities, chlorophyll content, total soluble sugars, proline content and lower levels of ROS, ion leakage were recorded when compared to the WT during cold stress (4°C), besides increase in yield. In the present study, Confocal and SEM analysis in conjunction with qPCR data on the expression pattern of lignin biosynthetic pathway genes revealed that the cold stress tolerance of the transgenic plants might be because of the peroxide induced up-regulation of lignin by antioxidant genes mediated triggering. PMID:25330211

  10. Elevated salicylic acid levels conferred by increased expression of ISOCHORISMATE SYNTHASE 1 contribute to hyperaccumulation of SUMO1 conjugates in the Arabidopsis mutant early in short days 4.

    PubMed

    Villajuana-Bonequi, Mitzi; Elrouby, Nabil; Nordström, Karl; Griebel, Thomas; Bachmair, Andreas; Coupland, George

    2014-07-01

    Post-translational modification of proteins by attachment of small ubiquitin-like modifier (SUMO) is essential for plant growth and development. Mutations in the SUMO protease early in short days 4 (ESD4) cause hyperaccumulation of conjugates formed between SUMO and its substrates, and phenotypically are associated with extreme early flowering and impaired growth. We performed a suppressor mutagenesis screen of esd4 and identified a series of mutants called suppressor of esd4 (sed), which delay flowering, enhance growth and reduce hyperaccumulation of SUMO conjugates. Genetic mapping and genome sequencing indicated that one of these mutations (sed111) is in the gene salicylic acid induction-deficient 2 (SID2), which encodes ISOCHORISMATE SYNTHASE I, an enzyme required for biosynthesis of salicylic acid (SA). Analyses showed that compared with wild-type plants, esd4 contains higher levels of SID2 mRNA and about threefold more SA, whereas sed111 contains lower SA levels. Other sed mutants also contain lower SA levels but are not mutant for SID2, although most reduce SID2 mRNA levels. Therefore, higher SA levels contribute to the small size, early flowering and elevated SUMO conjugate levels of esd4. Our results support previous data indicating that SUMO homeostasis influences SA biosynthesis in wild-type plants, and also demonstrate that elevated levels of SA strongly increase the abundance of SUMO conjugates.

  11. Complement factor H, FHR-3 and FHR-1 variants associate in an extended haplotype conferring increased risk of atypical hemolytic uremic syndrome.

    PubMed

    Bernabéu-Herrero, Maria E; Jiménez-Alcázar, Miguel; Anter, Jaouad; Pinto, Sheila; Sánchez Chinchilla, Daniel; Garrido, Sofía; López-Trascasa, Margarita; Rodríguez de Córdoba, Santiago; Sánchez-Corral, Pilar

    2015-10-01

    Atypical hemolytic uremic syndrome (aHUS) is a severe thrombotic microangiopathy affecting the renal microvasculature and is associated with complement dysregulation caused by mutations or autoantibodies. Disease penetrance and severity is modulated by inheritance of "risk" polymorphisms in the complement genes MCP, CFH and CFHR1. We describe the prevalence of mutations, the frequency of risk polymorphisms and the occurrence of anti-FH autoantibodies in a Spanish aHUS cohort (n=367). We also report the identification of a polymorphism in CFHR3 (c.721C>T; rs379370) that is associated with increased risk of aHUS (OR=1.78; CI 1.22-2.59; p=0.002), and is most frequently included in an extended risk haplotype spanning the CFH-CFHR3-CFHR1 genes. This extended haplotype integrates polymorphisms in the promoter region of CFH and CFHR3, and is associated with poorer evolution of renal function and decreased FH levels. The CFH-CFHR3-CFHR1 aHUS-risk haplotype seems to be the same as was previously associated with protection against meningococcal infections, suggesting that the genetic variability in this region is limited to a few extended haplotypes, each with opposite effects in various human diseases. These results suggest that the combination of quantitative and qualitative variations in the complement proteins encoded by CFH, CFHR3 and CFHR1 genes is key for the association of these haplotypes with disease.

  12. Overexpression of the phosphatidylinositol synthase gene (ZmPIS) conferring drought stress tolerance by altering membrane lipid composition and increasing ABA synthesis in maize.

    PubMed

    Liu, Xiuxia; Zhai, Shumei; Zhao, Yajie; Sun, Baocheng; Liu, Cheng; Yang, Aifang; Zhang, Juren

    2013-05-01

    Phosphatidylinositol (PtdIns) synthase is a key enzyme in the phospholipid pathway and catalyses the formation of PtdIns. PtdIns is not only a structural component of cell membranes, but also the precursor of the phospholipid signal molecules that regulate plant response to environment stresses. Here, we obtained transgenic maize constitutively overexpressing or underexpressing PIS from maize (ZmPIS) under the control of a maize ubiquitin promoter. Transgenic plants were confirmed by PCR, Southern blotting analysis and real-time RT-PCR assay. The electrospray ionization tandem mass spectrometry (ESI-MS/MS)-based lipid profiling analysis showed that, under drought stress conditions, the overexpression of ZmPIS in maize resulted in significantly elevated levels of most phospholipids and galactolipids in leaves compared with those in wild type (WT). At the same time, the expression of some genes involved in the phospholipid metabolism pathway and the abscisic acid (ABA) biosynthesis pathway including ZmPLC, ZmPLD, ZmDGK1, ZmDGK3, ZmPIP5K9, ZmABA1, ZmNCED, ZmAAO1, ZmAAO2 and ZmSCA1 was markedly up-regulated in the overexpression lines after drought stress. Consistent with these results, the drought stress tolerance of the ZmPIS sense transgenic plants was enhanced significantly at the pre-flowering stages compared with WT maize plants. These results imply that ZmPIS regulates the plant response to drought stress through altering membrane lipid composition and increasing ABA synthesis in maize.

  13. A mutation in the uvi4 gene promotes progression of endo-reduplication and confers increased tolerance towards ultraviolet B light.

    PubMed

    Hase, Yoshihiro; Trung, Khuat Huu; Matsunaga, Tsukasa; Tanaka, Atsushi

    2006-04-01

    We have isolated and characterized a new ultraviolet B (UV-B)-resistant mutant, uvi4 (UV-B-insensitive 4), of Arabidopsis. The fresh weight (FW) of uvi4 plants grown under supplemental UV-B light was more than twice that of the wild-type. No significant difference was found in their ability to repair the UV-B-induced cyclobutane pyrimidine dimers, or in the amount of UV-B absorptive compounds, both of which are well-known factors that contribute to UV sensitivity. Positional cloning revealed that the UVI4 gene encodes a novel basic protein of unknown function. We found that the hypocotyl cells in uvi4 undergo one extra round of endo-reduplication. The uvi4 mutation also promoted the progression of endo-reduplication during leaf development. The UVI4 gene is expressed mainly in actively dividing cells. In the leaves of P(UVI4)::GUS plants, the GUS signal disappeared in basipetal fashion as the leaf developed. The total leaf blade area was not different between uvi4 and the wild-type through leaf development, while the average cell area in the adaxial epidermis was considerably larger in uvi4, suggesting that the uvi4 leaves have fewer but larger epidermal cells. These results suggest that UVI4 is necessary for the maintenance of the mitotic state, and the loss of UVI4 function stimulated endo-reduplication. Tetraploid Arabidopsis was hyper-resistant to UV-B compared to diploid Arabidopsis, suggesting that the enhanced polyploidization is responsible for the increased UV-B tolerance of the uvi4 mutant.

  14. Symmetry Breaking During Drosophila Oogenesis

    PubMed Central

    Roth, Siegfried; Lynch, Jeremy A.

    2009-01-01

    The orthogonal axes of Drosophila are established during oogenesis through a hierarchical series of symmetry-breaking steps, most of which can be traced back to asymmetries inherent in the architecture of the ovary. Oogenesis begins with the formation of a germline cyst of 16 cells connected by ring canals. Two of these 16 cells have four ring canals, whereas the others have fewer. The first symmetry-breaking step is the selection of one of these two cells to become the oocyte. Subsequently, the germline cyst becomes surrounded by somatic follicle cells to generate individual egg chambers. The second symmetry-breaking step is the posterior positioning of the oocyte within the egg chamber, a process mediated by adhesive interactions with a special group of somatic cells. Posterior oocyte positioning is accompanied by a par gene-dependent repolarization of the microtubule network, which establishes the posterior cortex of the oocyte. The next two steps of symmetry breaking occur during midoogenesis after the volume of the oocyte has increased about 10-fold. First, a signal from the oocyte specifies posterior follicle cells, polarizing a symmetric prepattern present within the follicular epithelium. Second, the posterior follicle cells send a signal back to the oocyte, which leads to a second repolarization of the oocyte microtubule network and the asymmetric migration of the oocyte nucleus. This process again requires the par genes. The repolarization of the microtubule network results in the transport of bicoid and oskar mRNAs, the anterior and posterior determinants, respectively, of the embryonic axis, to opposite poles of the oocyte. The asymmetric positioning of the oocyte nucleus defines a cortical region of the oocyte where gurken mRNA is localized, thus breaking the dorsal–ventral symmetry of the egg and embryo. PMID:20066085

  15. Signaling by Drosophila capa neuropeptides.

    PubMed

    Davies, Shireen-A; Cabrero, Pablo; Povsic, Manca; Johnston, Natalie R; Terhzaz, Selim; Dow, Julian A T

    2013-07-01

    The capa peptide family, originally identified in the tobacco hawk moth, Manduca sexta, is now known to be present in many insect families, with increasing publications on capa neuropeptides each year. The physiological actions of capa peptides vary depending on the insect species but capa peptides have key myomodulatory and osmoregulatory functions, depending on insect lifestyle, and life stage. Capa peptide signaling is thus critical for fluid homeostasis and survival, making study of this neuropeptide family attractive for novel routes for insect control. In Dipteran species, including the genetically tractable Drosophila melanogaster, capa peptide action is diuretic; via elevation of nitric oxide, cGMP and calcium in the principal cells of the Malpighian tubules. The identification of the capa receptor (capaR) in several insect species has shown this to be a canonical GPCR. In D. melanogaster, ligand-activated capaR activity occurs in a dose-dependent manner between 10(-6) and 10(-12)M. Lower concentrations of capa peptide do not activate capaR, either in adult or larval Malpighian tubules. Use of transgenic flies in which capaR is knocked-down in only Malpighian tubule principal cells demonstrates that capaR modulates tubule fluid secretion rates and in doing so, sets the organismal response to desiccation. Thus, capa regulates a desiccation-responsive pathway in D. melanogaster, linking its role in osmoregulation and fluid homeostasis to environmental response and survival. The conservation of capa action between some Dipteran species suggests that capa's role in desiccation tolerance may not be confined to D. melanogaster.

  16. Iron Absorption in Drosophila melanogaster

    PubMed Central

    Mandilaras, Konstantinos; Pathmanathan, Tharse; Missirlis, Fanis

    2013-01-01

    The way in which Drosophila melanogaster acquires iron from the diet remains poorly understood despite iron absorption being of vital significance for larval growth. To describe the process of organismal iron absorption, consideration needs to be given to cellular iron import, storage, export and how intestinal epithelial cells sense and respond to iron availability. Here we review studies on the Divalent Metal Transporter-1 homolog Malvolio (iron import), the recent discovery that Multicopper Oxidase-1 has ferroxidase activity (iron export) and the role of ferritin in the process of iron acquisition (iron storage). We also describe what is known about iron regulation in insect cells. We then draw upon knowledge from mammalian iron homeostasis to identify candidate genes in flies. Questions arise from the lack of conservation in Drosophila for key mammalian players, such as ferroportin, hepcidin and all the components of the hemochromatosis-related pathway. Drosophila and other insects also lack erythropoiesis. Thus, systemic iron regulation is likely to be conveyed by different signaling pathways and tissue requirements. The significance of regulating intestinal iron uptake is inferred from reports linking Drosophila developmental, immune, heat-shock and behavioral responses to iron sequestration. PMID:23686013

  17. Iron absorption in Drosophila melanogaster.

    PubMed

    Mandilaras, Konstantinos; Pathmanathan, Tharse; Missirlis, Fanis

    2013-05-17

    The way in which Drosophila melanogaster acquires iron from the diet remains poorly understood despite iron absorption being of vital significance for larval growth. To describe the process of organismal iron absorption, consideration needs to be given to cellular iron import, storage, export and how intestinal epithelial cells sense and respond to iron availability. Here we review studies on the Divalent Metal Transporter-1 homolog Malvolio (iron import), the recent discovery that Multicopper Oxidase-1 has ferroxidase activity (iron export) and the role of ferritin in the process of iron acquisition (iron storage). We also describe what is known about iron regulation in insect cells. We then draw upon knowledge from mammalian iron homeostasis to identify candidate genes in flies. Questions arise from the lack of conservation in Drosophila for key mammalian players, such as ferroportin, hepcidin and all the components of the hemochromatosis-related pathway. Drosophila and other insects also lack erythropoiesis. Thus, systemic iron regulation is likely to be conveyed by different signaling pathways and tissue requirements. The significance of regulating intestinal iron uptake is inferred from reports linking Drosophila developmental, immune, heat-shock and behavioral responses to iron sequestration.

  18. PREFACE: Wake Conference 2015

    NASA Astrophysics Data System (ADS)

    Barney, Andrew; Nørkær Sørensen, Jens; Ivanell, Stefan

    2015-06-01

    The 44 papers in this volume constitute the proceedings of the 2015 Wake Conference, held in Visby on the island of Gotland in Sweden. It is the fourth time this conference has been held. The Wake Conference series started in Visby, where it was held in 2009 and 2011. In 2013 it took place in Copenhagen where it was combined with the International Conference on Offshore Wind Energy and Ocean Energy. In 2015 it is back where it started in Visby, where it takes place at Uppsala University Campus Gotland, June 9th-11th. The global yearly production of electrical energy by wind turbines has grown tremendously in the past decade and it now comprises more than 3% of the global electrical power consumption. Today the wind power industry has a global annual turnover of more than 50 billion USD and an annual average growth rate of more than 20%. State-of-the-art wind turbines have rotor diameters of up to 150 m and 8 MW installed capacity. These turbines are often placed in large wind farms that have a total production capacity corresponding to that of a nuclear power plant. In order to make a substantial impact on one of the most significant challenges of our time, global warming, the industry's growth has to continue for a decade or two yet. This in turn requires research into the physics of wind turbine wakes and wind farms. Modern wind turbines are today clustered in wind farms in which the turbines are fully or partially influenced by the wake of upstream turbines. As a consequence, the wake behind the wind turbines has a lower mean wind speed and an increased turbulence level, as compared to the undisturbed flow outside the farm. Hence, wake interaction results in decreased total production of power, caused by lower kinetic energy in the wind, and an increase in the turbulence intensity. Therefore, understanding the physical nature of the vortices and their dynamics in the wake of a turbine is important for the optimal design of a wind farm. This conference is aimed

  19. Resources for Functional Genomics Studies in Drosophila melanogaster

    PubMed Central

    Mohr, Stephanie E.; Hu, Yanhui; Kim, Kevin; Housden, Benjamin E.; Perrimon, Norbert

    2014-01-01

    Drosophila melanogaster has become a system of choice for functional genomic studies. Many resources, including online databases and software tools, are now available to support design or identification of relevant fly stocks and reagents or analysis and mining of existing functional genomic, transcriptomic, proteomic, etc. datasets. These include large community collections of fly stocks and plasmid clones, “meta” information sites like FlyBase and FlyMine, and an increasing number of more specialized reagents, databases, and online tools. Here, we introduce key resources useful to plan large-scale functional genomics studies in Drosophila and to analyze, integrate, and mine the results of those studies in ways that facilitate identification of highest-confidence results and generation of new hypotheses. We also discuss ways in which existing resources can be used and might be improved and suggest a few areas of future development that would further support large- and small-scale studies in Drosophila and facilitate use of Drosophila information by the research community more generally. PMID:24653003

  20. Metabolic Activity of Radish Sprouts Derived Isothiocyanates in Drosophila melanogaster

    PubMed Central

    Baenas, Nieves; Piegholdt, Stefanie; Schloesser, Anke; Moreno, Diego A.; García-Viguera, Cristina; Rimbach, Gerald; Wagner, Anika E.

    2016-01-01

    We used Drosophila melanogaster as a model system to study the absorption, metabolism and potential health benefits of plant bioactives derived from radish sprouts (Raphanus sativus cv. Rambo), a Brassicaceae species rich in glucosinolates and other phytochemicals. Flies were subjected to a diet supplemented with lyophilized radish sprouts (10.6 g/L) for 10 days, containing high amounts of glucoraphenin and glucoraphasatin, which can be hydrolyzed by myrosinase to the isothiocyanates sulforaphene and raphasatin, respectively. We demonstrate that Drosophila melanogaster takes up and metabolizes isothiocyanates from radish sprouts through the detection of the metabolite sulforaphane-cysteine in fly homogenates. Moreover, we report a decrease in the glucose content of flies, an upregulation of spargel expression, the Drosophila homolog of the mammalian PPARγ-coactivator 1 α, as well as the inhibition of α-amylase and α-glucosidase in vitro. Overall, we show that the consumption of radish sprouts affects energy metabolism in Drosophila melanogaster which is reflected by lower glucose levels and an increased expression of spargel, a central player in mitochondrial biogenesis. These processes are often affected in chronic diseases associated with aging, including type II diabetes mellitus. PMID:26901196

  1. Octopamine Regulates Sleep in Drosophila through PKA Dependent Mechanisms

    PubMed Central

    Crocker, Amanda; Sehgal, Amita

    2008-01-01

    Sleep is a fundamental process, but its regulation and function are still not well understood. The Drosophila model for sleep provides a powerful system to address the genetic and molecular mechanisms underlying sleep and wakefulness. Here we show that a Drosophila biogenic amine, octopamine, is a potent wake-promoting signal. Mutations in the octopamine biosynthesis pathway produced a phenotype of increased sleep, which was restored to wild type levels by pharmacological treatment with octopamine. Moreover, electrical silencing of octopamine-producing cells decreased wakefulness while excitation of these neurons promoted wakefulness. Since protein kinase A (PKA) is a putative target of octopamine signaling and is also implicated in Drosophila sleep, we investigated its role in the effects of octopamine on sleep. We found that decreased PKA activity in neurons rendered flies insensitive to the wake-promoting effects of octopamine. However, this effect of PKA was not exerted in the mushroom bodies (MB), a site previously associated with PKA action on sleep. These studies identify a novel pathway that regulates sleep in Drosophila. PMID:18799671

  2. Molecular Evolution of the Testis TAFs of Drosophila

    PubMed Central

    Davis, Jerel C.; Lenkov, Kapa; Bolival, Benjamin; Fuller, Margaret T.; Petrov, Dmitri A.

    2009-01-01

    The basal transcription machinery is responsible for initiating transcription at core promoters. During metazoan evolution, its components have expanded in number and diversified to increase the complexity of transcriptional regulation in tissues and developmental stages. To explore the evolutionary events and forces underlying this diversification, we analyzed the evolution of the Drosophila testis TAFs (TBP-associated factors), paralogs of TAFs from the basal transcription factor TFIID that are essential for normal transcription during spermatogenesis of a large set of specific genes involved in terminal differentiation of male gametes. There are five testis-specific TAFs in Drosophila, each expressed only in primary spermatocytes and each a paralog of a different generally expressed TFIID subunit. An examination of the presence of paralogs across taxa as well as molecular clock dating indicates that all five testis TAFs likely arose within a span of ∼38 My 63–250 Ma by independent duplication events from their generally expressed paralogs. Furthermore, the evolution of the testis TAFs has been rapid, with apparent further accelerations in multiple Drosophila lineages. Analysis of between-species divergence and intraspecies polymorphism indicates that the major forces of evolution on these genes have been reduced purifying selection, pervasive positive selection, and coevolution. Other genes that exhibit similar patterns of evolution in the Drosophila lineages are also characterized by enriched expression in the testis, suggesting that the pervasive positive selection acting on the tTAFs is likely to be related to their expression in the testis. PMID:19244474

  3. Thermotaxis, circadian rhythms, and TRP channels in Drosophila

    PubMed Central

    Bellemer, Andrew

    2015-01-01

    The fruit fly Drosophila melanogaster is a poikilothermic organism that must detect and respond to both fine and coarse changes in environmental temperature in order maintain optimal body temperature, synchronize behavior to daily temperature fluctuations, and to avoid potentially injurious environmental hazards. Members of the Transient Receptor Potential (TRP) family of cation channels are well known for their activation by changes in temperature and their essential roles in sensory transduction in both invertebrates and vertebrates. The Drosophila genome encodes 13 TRP channels, and several of these have key sensory transduction and modulatory functions in allowing larval and adult flies to make fine temperature discriminations to attain optimal body temperature, detect and avoid large environmental temperature fluctuations, and make rapid escape responses to acutely noxious stimuli. Drosophila use multiple, redundant signaling pathways and neural circuits to execute these behaviors in response to both increases and decreases in temperature of varying magnitudes and time scales. A plethora of powerful molecular and genetic tools and the fly's simple, well-characterized nervous system have given Drosophila neurobiologists a powerful platform to study the cellular and molecular mechanisms of TRP channel function and how these mechanisms are conserved in vertebrates, as well as how these channels function within sensorimotor circuits to generate both simple and complex thermosensory behaviors. PMID:27227026

  4. Drosophila Females Undergo Genome Expansion after Interspecific Hybridization

    PubMed Central

    Romero-Soriano, Valèria; Burlet, Nelly; Vela, Doris; Fontdevila, Antonio; Vieira, Cristina; García Guerreiro, María Pilar

    2016-01-01

    Genome size (or C-value) can present a wide range of values among eukaryotes. This variation has been attributed to differences in the amplification and deletion of different noncoding repetitive sequences, particularly transposable elements (TEs). TEs can be activated under different stress conditions such as interspecific hybridization events, as described for several species of animals and plants. These massive transposition episodes can lead to considerable genome expansions that could ultimately be involved in hybrid speciation processes. Here, we describe the effects of hybridization and introgression on genome size of Drosophila hybrids. We measured the genome size of two close Drosophila species, Drosophila buzzatii and Drosophila koepferae, their F1 offspring and the offspring from three generations of backcrossed hybrids; where mobilization of up to 28 different TEs was previously detected. We show that hybrid females indeed present a genome expansion, especially in the first backcross, which could likely be explained by transposition events. Hybrid males, which exhibit more variable C-values among individuals of the same generation, do not present an increased genome size. Thus, we demonstrate that the impact of hybridization on genome size can be detected through flow cytometry and is sex-dependent. PMID:26872773

  5. Metabolic Activity of Radish Sprouts Derived Isothiocyanates in Drosophila melanogaster.

    PubMed

    Baenas, Nieves; Piegholdt, Stefanie; Schloesser, Anke; Moreno, Diego A; García-Viguera, Cristina; Rimbach, Gerald; Wagner, Anika E

    2016-02-18

    We used Drosophila melanogaster as a model system to study the absorption, metabolism and potential health benefits of plant bioactives derived from radish sprouts (Raphanus sativus cv. Rambo), a Brassicaceae species rich in glucosinolates and other phytochemicals. Flies were subjected to a diet supplemented with lyophilized radish sprouts (10.6 g/L) for 10 days, containing high amounts of glucoraphenin and glucoraphasatin, which can be hydrolyzed by myrosinase to the isothiocyanates sulforaphene and raphasatin, respectively. We demonstrate that Drosophila melanogaster takes up and metabolizes isothiocyanates from radish sprouts through the detection of the metabolite sulforaphane-cysteine in fly homogenates. Moreover, we report a decrease in the glucose content of flies, an upregulation of spargel expression, the Drosophila homolog of the mammalian PPARγ-coactivator 1 α, as well as the inhibition of α-amylase and α-glucosidase in vitro. Overall, we show that the consumption of radish sprouts affects energy metabolism in Drosophila melanogaster which is reflected by lower glucose levels and an increased expression of spargel, a central player in mitochondrial biogenesis. These processes are often affected in chronic diseases associated with aging, including type II diabetes mellitus.

  6. Methods to assay Drosophila behavior.

    PubMed

    Nichols, Charles D; Becnel, Jaime; Pandey, Udai B

    2012-03-07

    Drosophila melanogaster, the fruit fly, has been used to study molecular mechanisms of a wide range of human diseases such as cancer, cardiovascular disease and various neurological diseases(1). We have optimized simple and robust behavioral assays for determining larval locomotion, adult climbing ability (RING assay), and courtship behaviors of Drosophila. These behavioral assays are widely applicable for studying the role of genetic and environmental factors on fly behavior. Larval crawling ability can be reliably used for determining early stage changes in the crawling abilities of Drosophila larvae and also for examining effect of drugs or human disease genes (in transgenic flies) on their locomotion. The larval crawling assay becomes more applicable if expression or abolition of a gene causes lethality in pupal or adult stages, as these flies do not survive to adulthood where they otherwise could be assessed. This basic assay can also be used in conjunction with bright light or stress to examine additional behavioral responses in Drosophila larvae. Courtship behavior has been widely used to investigate genetic basis of sexual behavior, and can also be used to examine activity and coordination, as well as learning and memory. Drosophila courtship behavior involves the exchange of various sensory stimuli including visual, auditory, and chemosensory signals between males and females that lead to a complex series of well characterized motor behaviors culminating in successful copulation. Traditional adult climbing assays (negative geotaxis) are tedious, labor intensive, and time consuming, with significant variation between different trials(2-4). The rapid iterative negative geotaxis (RING) assay(5) has many advantages over more widely employed protocols, providing a reproducible, sensitive, and high throughput approach to quantify adult locomotor and negative geotaxis behaviors. In the RING assay, several genotypes or drug treatments can be tested simultaneously

  7. Multiple P450s and Variation in Neuronal Genes Underpins the Response to the Insecticide Imidacloprid in a Population of Drosophila melanogaster.

    PubMed

    Denecke, Shane; Fusetto, Roberto; Martelli, Felipe; Giang, Alex; Battlay, Paul; Fournier-Level, Alexandre; O' Hair, Richard A; Batterham, Philip

    2017-09-12

    Insecticide resistance is an economically important example of evolution in response to intense selection pressure. Here, the genetics of resistance to the neonicotinoid insecticide imidacloprid is explored using the Drosophila Genetic Reference Panel, a collection of inbred Drosophila melanogaster genotypes derived from a single population in North Carolina. Imidacloprid resistance varied substantially among genotypes, and more resistant genotypes tended to show increased capacity to metabolize and excrete imidacloprid. Variation in resistance level was then associated with genomic and transcriptomic variation, implicating several candidate genes involved in central nervous system function and the cytochrome P450s Cyp6g1 and Cyp6g2. CRISPR-Cas9 mediated removal of Cyp6g1 suggested that it contributed to imidacloprid resistance only in backgrounds where it was already highly expressed. Cyp6g2, previously implicated in juvenile hormone synthesis via expression in the ring gland, was shown to be expressed in metabolically relevant tissues of resistant genotypes. Cyp6g2 overexpression was shown to both metabolize imidacloprid and confer resistance. These data collectively suggest that imidacloprid resistance is influenced by a variety of previously known and unknown genetic factors.

  8. Dominant-negative mutation in the beta2 and beta6 proteasome subunit genes affect alternative cell fate decisions in the Drosophila sense organ lineage.

    PubMed

    Schweisguth, F

    1999-09-28

    In Drosophila, dominant-negative mutations in the beta2 and beta6 proteasome catalytic subunit genes have been identified as dominant temperature-sensitive (DTS) mutations. At restrictive temperature, beta2 and beta6 DTS mutations confer lethality at the pupal stage. I investigate here the role of proteasome activity in regulating cell fate decisions in the sense organ lineage at the early pupal stage. Temperature-shift experiments in beta2 and beta6 DTS mutant pupae occasionally resulted in external sense organs with two sockets and no shaft. This double-socket phenotype was strongly enhanced in conditions in which Notch signaling was up-regulated. Furthermore, conditional overexpression of the beta6 dominant-negative mutant subunit led to shaft-to-socket and to neuron-to-sheath cell fate transformations, which are both usually associated with increased Notch signaling activity. Finally, expression of the beta6 dominant-negative mutant subunit led to the stabilization of an ectopically expressed nuclear form of Notch in imaginal wing discs. This study demonstrates that mutations affecting two distinct proteasome catalytic subunits affect two alternative cell fate decisions and enhance Notch signaling activity in the sense organ lineage. These findings raise the possibility that the proteasome targets an active form of the Notch receptor for degradation in Drosophila.

  9. Evolution of heterochromatic genes of Drosophila

    PubMed Central

    Yasuhara, Jiro C.; DeCrease, Christine H.; Wakimoto, Barbara T.

    2005-01-01

    Heterochromatin is generally associated with gene silencing, yet in Drosophila melanogaster, heterochromatin harbors hundreds of functional protein-encoding genes, some of which depend on heterochromatin for expression. Here we document a recent evolutionary transition of a gene cluster from euchromatin to heterochromatin, which occurred <20 million years ago in the drosophilid lineage. This finding reveals evolutionary fluidity between these two genomic compartments and provides a powerful approach to identifying differences between euchromatic and heterochromatic genes. Promoter mapping of orthologous gene pairs led to the discovery of the “slippery promoter,” characterized by multiple transcriptional start sites predominately at adenines, as a common promoter type found in both heterochromatic and euchromatic genes of Drosophila. Promoter type is diverse within the gene cluster but largely conserved between heterochromatic and euchromatic genes, eliminating the hypothesis that adaptation to heterochromatin required major alterations in promoter structure. Transition to heterochromatin is consistently associated with gene expansion due to the accumulation of transposable elements and increased A-T content. We conclude that heterochromatin-dependent regulation requires specialized enhancers or higher-order interactions and propose a facilitating role for transposable elements. PMID:16033869

  10. A Drosophila ABC Transporter Regulates Lifespan

    PubMed Central

    Huang, He; Lu-Bo, Ying; Haddad, Gabriel G.

    2014-01-01

    MRP4 (multidrug resistance-associated protein 4) is a member of the MRP/ABCC subfamily of ATP-binding cassette (ABC) transporters that are essential for many cellular processes requiring the transport of substrates across cell membranes. Although MRP4 has been implicated as a detoxification protein by transport of structurally diverse endogenous and xenobiotic compounds, including antivirus and anticancer drugs, that usually induce oxidative stress in cells, its in vivo biological function remains unknown. In this study, we investigate the biological functions of a Drosophila homolog of human MRP4, dMRP4. We show that dMRP4 expression is elevated in response to oxidative stress (paraquat, hydrogen peroxide and hyperoxia) in Drosophila. Flies lacking dMRP4 have a shortened lifespan under both oxidative and normal conditions. Overexpression of dMRP4, on the other hand, is sufficient to increase oxidative stress resistance and extend lifespan. By genetic manipulations, we demonstrate that dMRP4 is required for JNK (c-Jun NH2-terminal kinase) activation during paraquat challenge and for basal transcription of some JNK target genes under normal condition. We show that impaired JNK signaling is an important cause for major defects associated with dMRP4 mutations, suggesting that dMRP4 regulates lifespan by modulating the expression of a set of genes related to both oxidative resistance and aging, at least in part, through JNK signaling. PMID:25474322

  11. Fascin regulates nuclear actin during Drosophila oogenesis

    PubMed Central

    Kelpsch, Daniel J.; Groen, Christopher M.; Fagan, Tiffany N.; Sudhir, Sweta; Tootle, Tina L.

    2016-01-01

    Drosophila oogenesis provides a developmental system with which to study nuclear actin. During Stages 5–9, nuclear actin levels are high in the oocyte and exhibit variation within the nurse cells. Cofilin and Profilin, which regulate the nuclear import and export of actin, also localize to the nuclei. Expression of GFP-tagged Actin results in nuclear actin rod formation. These findings indicate that nuclear actin must be tightly regulated during oogenesis. One factor mediating this regulation is Fascin. Overexpression of Fascin enhances nuclear GFP-Actin rod formation, and Fascin colocalizes with the rods. Loss of Fascin reduces, whereas overexpression of Fascin increases, the frequency of nurse cells with high levels of nuclear actin, but neither alters the overall nuclear level of actin within the ovary. These data suggest that Fascin regulates the ability of specific cells to accumulate nuclear actin. Evidence indicates that Fascin positively regulates nuclear actin through Cofilin. Loss of Fascin results in decreased nuclear Cofilin. In addition, Fascin and Cofilin genetically interact, as double heterozygotes exhibit a reduction in the number of nurse cells with high nuclear actin levels. These findings are likely applicable beyond Drosophila follicle development, as the localization and functions of Fascin and the mechanisms regulating nuclear actin are widely conserved. PMID:27535426

  12. Cellular Mechanisms of Drosophila Heart Morphogenesis

    PubMed Central

    Vogler, Georg; Bodmer, Rolf

    2015-01-01

    Many of the major discoveries in the fields of genetics and developmental biology have been made using the fruit fly, Drosophila melanogaster. With regard to heart development, the conserved network of core cardiac transcription factors that underlies cardiogenesis has been studied in great detail in the fly, and the importance of several signaling pathways that regulate heart morphogenesis, such as Slit/Robo, was first shown in the fly model. Recent technological advances have led to a large increase in the genomic data available from patients with congenital heart disease (CHD). This has highlighted a number of candidate genes and gene networks that are potentially involved in CHD. To validate genes and genetic interactions among candidate CHD-causing alleles and to better understand heart formation in general are major tasks. The specific limitations of the various cardiac model systems currently employed (mammalian and fish models) provide a niche for the fly model, despite its evolutionary distance to vertebrates and humans. Here, we review recent advances made using the Drosophila embryo that identify factors relevant for heart formation. These underline how this model organism still is invaluable for a better understanding of CHD. PMID:26236710

  13. Evolutionary Changes in Gene Expression, Coding Sequence and Copy-Number at the Cyp6g1 Locus Contribute to Resistance to Multiple Insecticides in Drosophila

    PubMed Central

    Harrop, Thomas W. R.; Sztal, Tamar; Lumb, Christopher; Good, Robert T.; Daborn, Phillip J.; Batterham, Philip; Chung, Henry

    2014-01-01

    Widespread use of insecticides has led to insecticide resistance in many populations of insects. In some populations, resistance has evolved to multiple pesticides. In Drosophila melanogaster, resistance to multiple classes of insecticide is due to the overexpression of a single cytochrome P450 gene, Cyp6g1. Overexpression of Cyp6g1 appears to have evolved in parallel in Drosophila simulans, a sibling species of D. melanogaster, where it is also associated with insecticide resistance. However, it is not known whether the ability of the CYP6G1 enzyme to provide resistance to multiple insecticides evolved recently in D. melanogaster or if this function is present in all Drosophila species. Here we show that duplication of the Cyp6g1 gene occurred at least four times during the evolution of different Drosophila species, and the ability of CYP6G1 to confer resistance to multiple insecticides exists in D. melanogaster and D. simulans but not in Drosophila willistoni or Drosophila virilis. In D. virilis, which has multiple copies of Cyp6g1, one copy confers resistance to DDT and another to nitenpyram, suggesting that the divergence of protein sequence between copies subsequent to the duplication affected the activity of the enzyme. All orthologs tested conferred resistance to one or more insecticides, suggesting that CYP6G1 had the capacity to provide resistance to anthropogenic chemicals before they existed. Finally, we show that expression of Cyp6g1 in the Malpighian tubules, which contributes to DDT resistance in D. melanogaster, is specific to the D. melanogaster–D. simulans lineage. Our results suggest that a combination of gene duplication, regulatory changes and protein coding changes has taken place at the Cyp6g1 locus during evolution and this locus may play a role in providing resistance to different environmental toxins in different Drosophila species. PMID:24416303

  14. PREFACE: XXI Fluid Mechanics Conference

    NASA Astrophysics Data System (ADS)

    Szmyd, Janusz S.; Fornalik-Wajs, Elzbieta; Jaszczur, Marek

    2014-08-01

    papers were accepted for Proceedings published in the Journal of Physics: Conference Series. The total number of submitted and accepted papers for this year's conference represents a significant increase over previous Fluid Mechanics Conferences, and has expanded its initial national character and borders which speaks to the great vitality of fluid mechanics. We hope that these proceedings will be used not only as a document of the event but also to assess achievements and new paths to be taken in fluid mechanics research. Finally, we would like to congratulate the winners of the 2014 Professor Janusz W Elsner Competition Ruri Hidema from Japan, Fernando Tejero from Spain and Lukasz Laniewski-Wollk from Poland. Acknowledgements We would like to express grateful appreciation to our colleagues from the Polish Academy of Sciences, Committee of Mechanics, as well as to the International Scientific Committee i.e. Members and the Advisory Board. Their advice and efforts have helped us to overcome the problems normally associated with organising international meetings. Special thanks goes to the reviewers for their work in encouraging the submission of papers and the subsequent review of all papers. Their contribution cannot be overestimated. The 21st Fluid Mechanics Conference was organised by AGH University of Science and Technology, the Polish Academy of Sciences the Committee of Mechanics and the AGH-UST Foundation. Proceedings was published in the Journal of Physics: Conference Series. The demanding work involved could not have been done without the contribution of so many individuals from all institutions as well as numerous external co-workers. Without their extremely valuable help such a meeting would have been impossible. Thank you all so much! Details of the committees are available in the PDF

  15. Rural Energy Conference Project

    SciTech Connect

    Dennis Witmer; Shannon Watson

    2008-12-31

    Alaska remains, even at the beginning of the 21st century, a place with many widely scattered, small, remote communities, well beyond the end of both the road system and the power grid. These communities have the highest energy costs of any place in the United States, despite the best efforts of the utilities that service them. This is due to the widespread dependence on diesel electric generators, which require small capital investments, but recent increases in crude oil prices have resulted in dramatic increases in the cost of power. In the enabling legislation for the Arctic Energy Office in 2001, specific inclusion was made for the study of ways of reducing the cost of electrical power in these remote communities. As part of this mandate, the University of Alaska has, in conjunction with the US Department of Energy, the Denali Commission and the Alaska Energy Authority, organized a series of rural energy conferences, held approximately every 18 months. The goal of these meeting was to bring together rural utility operators, rural community leaders, government agency representatives, equipment suppliers, and researchers from universities and national laboratories to discuss the current state of the art in rural power generation, to discuss current projects, including successes as well as near successes. Many of the conference presenters were from industry and not accustomed to writing technical papers, so the typical method of organizing a conference by requesting abstracts and publishing proceedings was not considered viable. Instead, the organizing committee solicited presentations from appropriate individuals, and requested that (if they were comfortable with computers) prepare Power point presentations that were collected and posted on the web. This has become a repository of many presentations, and may be the best single source of information about current projects in the state of Alaska.

  16. Metabolic and target-site mechanisms combine to confer strong DDT resistance in Anopheles gambiae.

    PubMed

    Mitchell, Sara N; Rigden, Daniel J; Dowd, Andrew J; Lu, Fang; Wilding, Craig S; Weetman, David; Dadzie, Samuel; Jenkins, Adam M; Regna, Kimberly; Boko, Pelagie; Djogbenou, Luc; Muskavitch, Marc A T; Ranson, Hilary; Paine, Mark J I; Mayans, Olga; Donnelly, Martin J

    2014-01-01

    The development of resistance to insecticides has become a classic exemplar of evolution occurring within human time scales. In this study we demonstrate how resistance to DDT in the major African malaria vector Anopheles gambiae is a result of both target-site resistance mechanisms that have introgressed between incipient species (the M- and S-molecular forms) and allelic variants in a DDT-detoxifying enzyme. Sequencing of the detoxification enzyme, Gste2, from DDT resistant and susceptible strains of An. gambiae, revealed a non-synonymous polymorphism (I114T), proximal to the DDT binding domain, which segregated with strain phenotype. Recombinant protein expression and DDT metabolism analysis revealed that the proteins from the susceptible strain lost activity at higher DDT concentrations, characteristic of substrate inhibition. The effect of I114T on GSTE2 protein structure was explored through X-ray crystallography. The amino acid exchange in the DDT-resistant strain introduced a hydroxyl group nearby the hydrophobic DDT-binding region. The exchange does not result in structural alterations but is predicted to facilitate local dynamics and enzyme activity. Expression of both wild-type and 114T alleles the allele in Drosophila conferred an increase in DDT tolerance. The 114T mutation was significantly associated with DDT resistance in wild caught M-form populations and acts in concert with target-site mutations in the voltage gated sodium channel (Vgsc-1575Y and Vgsc-1014F) to confer extreme levels of DDT resistance in wild caught An. gambiae.

  17. Decanalization of wing development accompanied the evolution of large wings in high-altitude Drosophila

    PubMed Central

    Lack, Justin B.; Monette, Matthew J.; Johanning, Evan J.; Sprengelmeyer, Quentin D.; Pool, John E.

    2016-01-01

    In higher organisms, the phenotypic impacts of potentially harmful or beneficial mutations are often modulated by complex developmental networks. Stabilizing selection may favor the evolution of developmental canalization—that is, robustness despite perturbation—to insulate development against environmental and genetic variability. In contrast, directional selection acts to alter the developmental process, possibly undermining the molecular mechanisms that buffer a trait’s development, but this scenario has not been shown in nature. Here, we examined the developmental consequences of size increase in highland Ethiopian Drosophila melanogaster. Ethiopian inbred strains exhibited much higher frequencies of wing abnormalities than lowland populations, consistent with an elevated susceptibility to the genetic perturbation of inbreeding. We then used mutagenesis to test whether Ethiopian wing development is, indeed, decanalized. Ethiopian strains were far more susceptible to this genetic disruption of development, yielding 26 times more novel wing abnormalities than lowland strains in F2 males. Wing size and developmental perturbability cosegregated in the offspring of between-population crosses, suggesting that genes conferring size differences had undermined developmental buffering mechanisms. Our findings represent the first observation, to our knowledge, of morphological evolution associated with decanalization in the same tissue, underscoring the sensitivity of development to adaptive change. PMID:26755605

  18. Sleep fragmentation and motor restlessness in a Drosophila model of Restless Legs Syndrome.

    PubMed

    Freeman, Amanda; Pranski, Elaine; Miller, R Daniel; Radmard, Sara; Bernhard, Doug; Jinnah, H A; Betarbet, Ranjita; Rye, David B; Sanyal, Subhabrata

    2012-06-19

    Restless Legs Syndrome (RLS), first chronicled by Willis in 1672 and described in more detail by Ekbom in 1945, is a prevalent sensorimotor neurological disorder (5%-10% in the population) with a circadian predilection for the evening and night. Characteristic clinical features also include a compelling urge to move during periods of rest, relief with movement, involuntary movements in sleep (viz., periodic leg movements of sleep), and fragmented sleep. Although the pathophysiology of RLS is unknown, dopaminergic neurotransmission and deficits in iron availability modulate expressivity. Genome-wide association studies have identified a polymorphism in an intronic region of the BTBD9 gene on chromosome 6 that confers substantial risk for RLS. Here, we report that loss of the Drosophila homolog CG1826 (dBTBD9) appreciably disrupts sleep with concomitant increases in waking and motor activity. We further show that BTBD9 regulates brain dopamine levels in flies and controls iron homeostasis through the iron regulatory protein-2 in human cell lines. To our knowledge, this represents the first reverse genetic analysis of a "novel" or heretofore poorly understood gene implicated in an exceedingly common and complex sleep disorder and the development of an RLS animal model that closely recapitulates all disease phenotypes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Short term hardening effects on survival of acute and chronic cold exposure by Drosophila melanogaster larvae

    PubMed Central

    Rajamohan, Arun; Sinclair, Brent J.

    2008-01-01

    We quantified the variation and plasticity in cold tolerance among four larval stages of four laboratory strains of Drosophila melanogaster in response to both acute (<2 hours of cold exposure) and chronic (∼7 hours of cold exposure) cold exposure. We observed significant differences in basal cold tolerance between the strains and among larval stages. Early larval instars were generally more tolerant of acute cold exposures than 3rd instar larvae. However, wandering larvae were more tolerant of chronic cold exposures than the other stages. Early stages also displayed a more pronounced rapid cold-hardening response than the later stages. Heat pre-treatment did not confer a significant increase in cold tolerance to any of the strains at any stage, pointing to different mechanisms being involved in resolving heat- and cold-elicited damage. However, when heat pre-treatment was combined with rapid cold-hardening as sequential pre-treatments, both positive (heat first) and negative (heat second) effects on cold tolerance were observed. We discuss possible mechanisms underlying cold-hardening and the effects of acute and chronic cold exposures. PMID:18342328

  20. Immune anticipation of mating in Drosophila: Turandot M promotes immunity against sexually transmitted fungal infections.

    PubMed

    Zhong, Weihao; McClure, Colin D; Evans, Cara R; Mlynski, David T; Immonen, Elina; Ritchie, Michael G; Priest, Nicholas K

    2013-12-22

    Although it is well known that mating increases the risk of infection, we do not know how females mitigate the fitness costs of sexually transmitted infections (STIs). It has recently been shown that female fruitflies, Drosophila melanogaster, specifically upregulate two members of the Turandot family of immune and stress response genes, Turandot M and Turandot C (TotM and TotC), when they hear male courtship song. Here, we use the Gal4/UAS RNAi gene knockdown system to test whether the expression of these genes provides fitness benefits for females infected with the entomopathogenic fungus, Metarhizium robertsii under sexual transmission. As a control, we also examined the immunity conferred by Dorsal-related immunity factor (Dif), a central component of the Toll signalling pathway thought to provide immunity against fungal infections. We show that TotM, but not TotC or Dif, provides survival benefits to females following STIs, but not after direct topical infections. We also show that though the expression of TotM provides fecundity benefits for healthy females, it comes at a cost to their survival, which helps to explain why TotM is not constitutively expressed. Together, these results show that the anticipatory expression of TotM promotes specific immunity against fungal STIs and suggest that immune anticipation is more common than currently appreciated.

  1. Immune anticipation of mating in Drosophila: Turandot M promotes immunity against sexually transmitted fungal infections

    PubMed Central

    Zhong, Weihao; McClure, Colin D.; Evans, Cara R.; Mlynski, David T.; Immonen, Elina; Ritchie, Michael G.; Priest, Nicholas K.

    2013-01-01

    Although it is well known that mating increases the risk of infection, we do not know how females mitigate the fitness costs of sexually transmitted infections (STIs). It has recently been shown that female fruitflies, Drosophila melanogaster, specifically upregulate two members of the Turandot family of immune and stress response genes, Turandot M and Turandot C (TotM and TotC), when they hear male courtship song. Here, we use the Gal4/UAS RNAi gene knockdown system to test whether the expression of these genes provides fitness benefits for females infected with the entomopathogenic fungus, Metarhizium robertsii under sexual transmission. As a control, we also examined the immunity conferred by Dorsal-related immunity factor (Dif), a central component of the Toll signalling pathway thought to provide immunity against fungal infections. We show that TotM, but not TotC or Dif, provides survival benefits to females following STIs, but not after direct topical infections. We also show that though the expression of TotM provides fecundity benefits for healthy females, it comes at a cost to their survival, which helps to explain why TotM is not constitutively expressed. Together, these results show that the anticipatory expression of TotM promotes specific immunity against fungal STIs and suggest that immune anticipation is more common than currently appreciated. PMID:24174107

  2. Forward and feedback regulation of cyclic steroid production in Drosophila melanogaster.

    PubMed

    Parvy, Jean-Philippe; Wang, Peng; Garrido, Damien; Maria, Annick; Blais, Catherine; Poidevin, Mickael; Montagne, Jacques

    2014-10-01

    In most animals, steroid hormones are crucial regulators of physiology and developmental life transitions. Steroid synthesis depends on extrinsic parameters and autoregulatory processes to fine-tune the dynamics of hormone production. In Drosophila, transient increases of the steroid prohormone ecdysone, produced at each larval stage, are necessary to trigger moulting and metamorphosis. Binding of the active ecdysone (20-hydroxyecdysone) to its receptor (EcR) is followed by the sequential expression of the nuclear receptors E75, DHR3 and βFtz-f1, representing a model for steroid hormone signalling. Here, we have combined genetic and imaging approaches to investigate the precise role of this signalling cascade within theprothoracic gland (PG), where ecdysone synthesis takes place. We show that these receptors operate through an apparent unconventional hierarchy in the PG to control ecdysone biosynthesis. At metamorphosis onset, DHR3 emerges as the downstream component that represses steroidogenic enzymes and requires an early effect of EcR for this repression. To avoid premature repression of steroidogenesis, E75 counteracts DHR3 activity, whereas EcR and βFtz-f1 act early in development through a forward process to moderate DHR3 levels. Our findings suggest that within the steroidogenic tissue, a given 20-hydroxyecdysone peak induces autoregulatory processes to sharpen ecdysone production and to confer competence for ecdysteroid biosynthesis at the next developmental phase, providing novel insights into steroid hormone kinetics.

  3. Hyperoxia-induced neurodegeneration as a tool to identify neuroprotective genes in Drosophila melanogaster.

    PubMed

    Gruenewald, Christoph; Botella, Jose A; Bayersdorfer, Florian; Navarro, Juan A; Schneuwly, Stephan

    2009-06-15

    Oxidative stress has been reported to be a common underlying mechanism in the pathogenesis of many neurodegenerative disorders such as Alzheimer, Huntington, Creutzfeld-Jakob, and Parkinson disease. Despite the increasing number of articles showing a correlation between oxidative damage and neurodegeneration little is known about the genetic elements that confer protection against the deleterious effects of an oxidative imbalance in neurons. We show that oxygen-induced damage is a direct cause of brain degeneration in Drosophila and establish an experimental setup measuring dopaminergic neuron survival to model oxidative stress-induced neurodegeneration in flies. The overexpression of superoxide dismutase but not catalase was able to protect dopaminergic neurons against oxidative imbalance under hyperoxia treatment. In an effort to identify new genes involved in the process of oxidative stress-induced neurodegeneration, we have carried out a genome-wide expression analysis to identify genes whose expression is upregulated in fly heads under hyperoxia. Among them, a number of mitochondrial and cytoplasmic chaperones could be identified and were shown to protect dopaminergic neurons when overexpressed, thus validating our approach to identifying new genes involved in the neuronal defense mechanism against oxidative stress.

  4. Small nuclear ribonucleoproteins of Drosophila: Identification of U1 RNA-associated proteins and their behavior during heat shock

    SciTech Connect

    Wieben, E.D.; Pederson, T.

    1982-08-01

    In Drosophila, two nuclear proteins of approximately 26,000 and 14,000 molecular weight are recognized by a human autoimmune antibody for mammalian ribonucleoprotein (RNP) particles that contain U1 small nuclear RNA. The antibody-selected Drosophila RNP contains, in addition to these two proteins, a single RNA species that has been identified as U1 by hybridization with a cloned Drosophila U1 DNA probe. Small nuclear RNP isolated from human cells under the same conditions as used for Drosophila and selected by the anti-U1 RNP-specific antibody contains eight proteins, two of which are similar in molecular weight to the two Drosophila U1 RNP proteins. Thus, even though the nucleotide sequences of Drosophila and human U1 RNA are about 72% homologous, and the corresponding RNPs are both recognized by the same human autoantibody, Drosophila U1 RNP appears to have a simpler protein complement that its mammalian counterpart. The two Drosophila U1 RNA-associated proteins are synthesized at normal or slightly increased rates during the heat shock response and are incorporated into antibody-recognizable RNP complexes. This raises the possibility that U1 RNP is an indispensable nuclear element for cell survival during heat shock.

  5. The Drosophila melanogaster Model for Cornelia de Lange Syndrome: Implications for Etiology and Therapeutics

    PubMed Central

    Dorsett, Dale

    2016-01-01

    Discovery of genetic alterations that cause human birth defects provide key opportunities to improve the diagnosis, treatment, and family counseling. Frequently, however, these opportunities are limited by the lack of knowledge about the normal functions of the affected genes. In many cases, there is more information about the gene’s orthologs in model organisms, including Drosophila melanogaster. Despite almost a billion years of evolutionary divergence, over three-quarters of genes linked to human diseases have Drosophila homologs. With a short generation time, a twenty-fold smaller genome, and unique genetic tools, the conserved functions of genes are often more easily elucidated in Drosophila than in other organisms. Here we present how this applies to Cornelia de Lange syndrome, as a model for how Drosophila can be used to increase understanding of genetic syndromes caused by mutations with broad effects on gene transcription and exploited to develop novel therapies. PMID:27097273

  6. The Drosophila melanogaster model for Cornelia de Lange syndrome: Implications for etiology and therapeutics.

    PubMed

    Dorsett, Dale

    2016-06-01

    Discovery of genetic alterations that cause human birth defects provide key opportunities to improve the diagnosis, treatment, and family counseling. Frequently, however, these opportunities are limited by the lack of knowledge about the normal functions of the affected genes. In many cases, there is more information about the gene's orthologs in model organisms, including Drosophila melanogaster. Despite almost a billion years of evolutionary divergence, over three-quarters of genes linked to human diseases have Drosophila homologs. With a short generation time, a twenty-fold smaller genome, and unique genetic tools, the conserved functions of genes are often more easily elucidated in Drosophila than in other organisms. Here we present how this applies to Cornelia de Lange syndrome, as a model for how Drosophila can be used to increase understanding of genetic syndromes caused by mutations with broad effects on gene transcription and exploited to develop novel therapies. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Conference Abstracts: AEDS '82.

    ERIC Educational Resources Information Center

    Journal of Computers in Mathematics and Science Teaching, 1982

    1982-01-01

    Abstracts from nine selected papers presented at the 1982 Association for Educational Data Systems (AEDS) conference are provided. Copies of conference proceedings may be obtained for fifteen dollars from the Association. (MP)

  8. Molecular genetic analysis of circadian timekeeping in Drosophila.

    PubMed

    Hardin, Paul E

    2011-01-01

    A genetic screen for mutants that alter circadian rhythms in Drosophila identified the first clock gene-the period (per) gene. The per gene is a central player within a transcriptional feedback loop that represents the core mechanism for keeping circadian time in Drosophila and other animals. The per feedback loop, or core loop, is interlocked with the Clock (Clk) feedback loop, but whether the Clk feedback loop contributes to circadian timekeeping is not known. A series of distinct molecular events are thought to control transcriptional feedback in the core loop. The time it takes to complete these events should take much less than 24h, thus delays must be imposed at different steps within the core loop. As new clock genes are identified, the molecular mechanisms responsible for these delays have been revealed in ever-increasing detail and provide an in-depth accounting of how transcriptional feedback loops keep circadian time. The phase of these feedback loops shifts to maintain synchrony with environmental cycles, the most reliable of which is light. Although a great deal is known about cell-autonomous mechanisms of light-induced phase shifting by CRYPTOCHROME (CRY), much less is known about non-cell autonomous mechanisms. CRY mediates phase shifts through an uncharacterized mechanism in certain brain oscillator neurons and carries out a dual role as a photoreceptor and transcription factor in other tissues. Here, I review how transcriptional feedback loops function to keep time in Drosophila, how they impose delays to maintain a 24-h cycle, and how they maintain synchrony with environmental light:dark cycles. The transcriptional feedback loops that keep time in Drosophila are well conserved in other animals, thus what we learn about these loops in Drosophila should continue to provide insight into the operation of analogous transcriptional feedback loops in other animals.

  9. Positive and purifying selection on the Drosophila Y chromosome.

    PubMed

    Singh, Nadia D; Koerich, Leonardo B; Carvalho, Antonio Bernardo; Clark, Andrew G

    2014-10-01

    Y chromosomes, with their reduced effective population size, lack of recombination, and male-limited transmission, present a unique collection of constraints for the operation of natural selection. Male-limited transmission may greatly increase the efficacy of selection for male-beneficial mutations, but the reduced effective size also inflates the role of random genetic drift. Together, these defining features of the Y chromosome are expected to influence rates and patterns of molecular evolution on the Y as compared with X-linked or autosomal loci. Here, we use sequence data from 11 genes in 9 Drosophila species to gain insight into the efficacy of natural selection on the Drosophila Y relative to the rest of the genome. Drosophila is an ideal system for assessing the consequences of Y-linkage for molecular evolution in part because the gene content of Drosophila Y chromosomes is highly dynamic, with orthologous genes being Y-linked in some species whereas autosomal in others. Our results confirm the expectation that the efficacy of natural selection at weakly selected sites is reduced on the Y chromosome. In contrast, purifying selection on the Y chromosome for strongly deleterious mutations does not appear to be compromised. Finally, we find evidence of recurrent positive selection for 4 of the 11 genes studied here. Our results thus highlight the variable nature of the mode and impact of natural selection on the Drosophila Y chromosome. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Sucrose Improves Insecticide Activity Against Drosophila suzukii (Diptera: Drosophilidae).

    PubMed

    Cowles, Richard S; Rodriguez-Saona, Cesar; Holdcraft, Robert; Loeb, Gregory M; Elsensohn, Johanna E; Hesler, Steven P

    2015-04-01

    The addition of sucrose to insecticides targeting spotted wing drosophila, Drosophila suzukii (Matsumura), enhanced lethality in laboratory, semifield, and field tests. In the laboratory, 0.1% sucrose added to a spray solution enhanced spotted wing drosophila feeding. Flies died 120 min earlier when exposed to spinosad residues at label rates enhanced with sucrose. Added sucrose reduced the LC50 for dried acetamiprid residues from 82 to 41 ppm in the spray solution. Laboratory bioassays of spotted wing drosophila mortality followed exposure to grape and blueberry foliage and/or fruit sprayed and aged in the field. On grape foliage, the addition of 2.4 g/liter of sugar with insecticide sprays resulted in an 11 and 6% increase of spotted wing drosophila mortality at 1 and 2 d exposures to residues, respectively, averaged over seven insecticides with three concentrations. In a separate experiment, spinetoram and cyantraniliprole reduced by 95-100% the larval infestation of blueberries, relative to the untreated control, 7 d after application at labeled rates when applied with 1.2 g/liter sucrose in a spray mixture, irrespective of rainfall; without sucrose infestation was reduced by 46-91%. Adding sugar to the organically acceptable spinosyn, Entrust, reduced larval infestation of strawberries by >50% relative to without sugar for five of the six sample dates during a season-long field trial. In a small-plot field test with blueberries, weekly applications in alternating sprays of sucrose plus reduced-risk insecticides, spinetoram or acetamiprid, reduced larval infestation relative to the untreated control by 76%; alternating bifenthrin and phosmet (without sucrose) reduced infestation by 65%.

  11. Multiple gustatory receptors required for the caffeine response in Drosophila

    PubMed Central

    Lee, Youngseok; Moon, Seok Jun; Montell, Craig

    2009-01-01

    The ability of insects to detect and avoid ingesting naturally occurring repellents and insecticides is essential for their survival. Nevertheless, the gustatory receptors enabling them to sense toxic botanical compounds are largely unknown. The only insect gustatory receptor shown to be required for avoiding noxious compounds is the Drosophila caffeine receptor, Gr66a. However, this receptor is not sufficient for the caffeine response, suggesting that Gr66a may be a subunit of a larger receptor. Here, we report that mutations in the gene encoding the gustatory receptor, Gr93a, result in a phenotype identical to that caused by mutations in Gr66a. This includes an inability to avoid caffeine or the related methylxanthine present in tea, theophylline. Caffeine-induced action potentials were also eliminated in Gr93a-mutant animals, while the flies displayed normal responses to other aversive compounds or to sugars. The Gr93a protein was coexpressed with Gr66a in avoidance-gustatory receptor neurons (GRNs), and functioned in the same GRNs as Gr66a. However, misexpression of both receptors in GRNs that normally do not express either Gr93a or Gr66a does not confer caffeine sensitivity to these GRNs. Because Gr93a- and Gr66a-mutant animals exhibit the identical phenotypes and function in the same cells, we propose that they may be caffeine coreceptors. In contrast to mammalian and Drosophila olfactory receptors and mammalian taste receptors, which are monomeric or dimeric receptors, we propose that Drosophila taste receptors that function in avoidance of bitter compounds are more complex and require additional subunits that remain to be identified. PMID:19246397

  12. Multiple gustatory receptors required for the caffeine response in Drosophila.

    PubMed

    Lee, Youngseok; Moon, Seok Jun; Montell, Craig

    2009-03-17

    The ability of insects to detect and avoid ingesting naturally occurring repellents and insecticides is essential for their survival. Nevertheless, the gustatory receptors enabling them to sense toxic botanical compounds are largely unknown. The only insect gustatory receptor shown to be required for avoiding noxious compounds is the Drosophila caffeine receptor, Gr66a. However, this receptor is not sufficient for the caffeine response, suggesting that Gr66a may be a subunit of a larger receptor. Here, we report that mutations in the gene encoding the gustatory receptor, Gr93a, result in a phenotype identical to that caused by mutations in Gr66a. This includes an inability to avoid caffeine or the related methylxanthine present in tea, theophylline. Caffeine-induced action potentials were also eliminated in Gr93a-mutant animals, while the flies displayed normal responses to other aversive compounds or to sugars. The Gr93a protein was coexpressed with Gr66a in avoidance-gustatory receptor neurons (GRNs), and functioned in the same GRNs as Gr66a. However, misexpression of both receptors in GRNs that normally do not express either Gr93a or Gr66a does not confer caffeine sensitivity to these GRNs. Because Gr93a- and Gr66a-mutant animals exhibit the identical phenotypes and function in the same cells, we propose that they may be caffeine coreceptors. In contrast to mammalian and Drosophila olfactory receptors and mammalian taste receptors, which are monomeric or dimeric receptors, we propose that Drosophila taste receptors that function in avoidance of bitter compounds are more complex and require additional subunits that remain to be identified.

  13. Glial dysfunction causes age-related memory impairment in Drosophila.

    PubMed

    Yamazaki, Daisuke; Horiuchi, Junjiro; Ueno, Kohei; Ueno, Taro; Saeki, Shinjiro; Matsuno, Motomi; Naganos, Shintaro; Miyashita, Tomoyuki; Hirano, Yukinori; Nishikawa, Hiroyuki; Taoka, Masato; Yamauchi, Yoshio; Isobe, Toshiaki; Honda, Yoshiko; Kodama, Tohru; Masuda, Tomoko; Saitoe, Minoru

    2014-11-19

    Several aging phenotypes, including age-related memory impairment (AMI), are thought to be caused by cumulative oxidative damage. In Drosophila, age-related impairments in 1 hr memory can be suppressed by reducing activity of protein kinase A (PKA). However, the mechanism for this effect has been unclear. Here we show that decreasing PKA suppresses AMI by reducing activity of pyruvate carboxylase (PC), a glial metabolic enzyme whose amounts increase upon aging. Increased PC activity causes AMI through a mechanism independent of oxidative damage. Instead, increased PC activity is associated with decreases in D-serine, a glia-derived neuromodulator that regulates NMDA receptor activity. D-serine feeding suppresses both AMI and memory impairment caused by glial overexpression of dPC, indicating that an oxidative stress-independent dysregulation of glial modulation of neuronal activity contributes to AMI in Drosophila.

  14. Parent Conferences. Beginnings Workshop.

    ERIC Educational Resources Information Center

    Duffy, Roslyn; And Others

    1997-01-01

    Presents six workshop sessions on parent conferences: (1) "Parents' Perspectives on Conferencing" (R. Duffy); (2) "Three Way Conferences" (G. Zeller); (3) "Conferencing with Parents of Infants" (K. Albrecht); (4) "Conferencing with Parents of School-Agers" (L. G. Miller); (5) "Cross Cultural Conferences" (J. Gonzalez-Mena); and (6) "Working with…

  15. EDITORIAL: Conference program

    NASA Astrophysics Data System (ADS)

    2006-04-01

    Some of the papers and talks given at the conference have not been published in this volume of Journal of Physics: Conference Series. The attached PDF file lists the full conference program and indicates (with an asterisk) those papers or talks which are not present in this volume.

  16. The General Conference Mennonites.

    ERIC Educational Resources Information Center

    Ediger, Marlow

    General Conference Mennonites and Old Order Amish are compared and contrasted in the areas of physical appearance, religious beliefs, formal education, methods of farming, and home settings. General Conference Mennonites and Amish differ in physical appearance and especially in dress. The General Conference Mennonite men and women dress the same…

  17. Youth Conference Handbook.

    ERIC Educational Resources Information Center

    Brown, Brenda H.

    This handbook is designed to provide practical aid to those who have charge of the planning and organization of a youth conference, Defined as a conference to provide practical information as well as information about possible responsibilities, risks, and consequences of actions, related to the chosen conference topic. Suggestions are given for…

  18. Detection of Volatile Indicators of Illicit Substances by the Olfactory Receptors of Drosophila melanogaster

    PubMed Central

    Marshall, Brenton; Warr, Coral G.

    2010-01-01

    Insects can detect a large range of odors with a numerically simple olfactory system that delivers high sensitivity and accurate discrimination. Therefore, insect olfactory receptors hold great promise as biosensors for detection of volatile organic chemicals in a range of applications. The array of olfactory receptor neurons of Drosophila melanogaster is rapidly becoming the best-characterized natural nose. We have investigated the suitability of Drosophila receptors as detectors for volatiles with applications in law enforcement, emergency response, and security. We first characterized responses of the majority of olfactory neuron types to a set of diagnostic odorants. Being thus able to correctly identify neurons, we then screened for responses from 38 different types of neurons to 35 agents. We identified 13 neuron types with responses to 13 agents. As individual Drosophila receptor genes have been mapped to neuron types, we can infer which genes confer responsiveness to the neurons. The responses were confirmed for one receptor by expressing it in a nonresponsive neuron. The fly olfactory system is mainly adapted to detect volatiles from fermenting fruits. However, our findings establish that volatiles associated with illicit substances, many of which are of nonnatural origin, are also detected by Drosophila receptors. PMID:20530374

  19. The Molecular and Cellular Basis of Bitter Taste in Drosophila

    PubMed Central

    Weiss, Linnea A.; Dahanukar, Anupama; Kwon, Jae Young; Banerjee, Diya; Carlson, John R.

    2011-01-01

    Summary The extent of diversity among bitter-sensing neurons is a fundamental issue in the field of taste. Data are limited and conflicting as to whether bitter neurons are broadly tuned and uniform, resulting in indiscriminate avoidance of bitter stimuli, or diverse, allowing a more discerning evaluation of food sources. We provide a systematic analysis of how bitter taste is encoded by the major taste organ of the Drosophila head, the labellum. Each of 16 bitter compounds is tested physiologically against all 31 bitter neurons, revealing responses that are diverse in magnitude and dynamics. Four functional classes of bitter neurons are defined. Four corresponding classes are defined through expression analysis of all 68 Gr taste receptors. A receptor-to-neuron-to-tastant map is constructed. Misexpression of one receptor confers bitter responses as predicted by the map. These results reveal a degree of complexity that greatly expands the capacity of the system to encode bitter taste. PMID:21262465

  20. Limited taste discrimination in Drosophila.

    PubMed

    Masek, Pavel; Scott, Kristin

    2010-08-17

    In the gustatory systems of mammals and flies, different populations of sensory cells recognize different taste modalities, such that there are cells that respond selectively to sugars and others to bitter compounds. This organization readily allows animals to distinguish compounds of different modalities but may limit the ability to distinguish compounds within one taste modality. Here, we developed a behavioral paradigm in Drosophila melanogaster to evaluate directly the tastes that a fly distinguishes. These studies reveal that flies do not discriminate among different sugars, or among different bitter compounds, based on chemical identity. Instead, flies show a limited ability to distinguish compounds within a modality based on intensity or palatability. Taste associative learning, similar to olfactory learning, requires the mushroom bodies, suggesting fundamental similarities in brain mechanisms underlying behavioral plasticity. Overall, these studies provide insight into the discriminative capacity of the Drosophila gustatory system and the modulation of taste behavior.

  1. A Drosophila complementary DNA resource

    SciTech Connect

    Rubin, Gerald M.; Hong, Ling; Brokstein, Peter; Evans-Holm, Martha; Frise, Erwin; Stapleton, Mark; Harvey, Damon A.

    2000-03-24

    Collections of nonredundant, full-length complementary DNA (cDNA) clones for each of the model organisms and humans will be important resources for studies of gene structure and function. We describe a general strategy for producing such collections and its implementation, which so far has generated a set of cDNAs corresponding to over 40% of the genes in the fruit fly Drosophila melanogaster.

  2. 'Peer pressure' in larval Drosophila?

    PubMed

    Niewalda, Thomas; Jeske, Ines; Michels, Birgit; Gerber, Bertram

    2014-06-06

    Understanding social behaviour requires a study case that is simple enough to be tractable, yet complex enough to remain interesting. Do larval Drosophila meet these requirements? In a broad sense, this question can refer to effects of the mere presence of other larvae on the behaviour of a target individual. Here we focused in a more strict sense on 'peer pressure', that is on the question of whether the behaviour of a target individual larva is affected by what a surrounding group of larvae is doing. We found that innate olfactory preference of a target individual was neither affected (i) by the level of innate olfactory preference in the surrounding group nor (ii) by the expression of learned olfactory preference in the group. Likewise, learned olfactory preference of a target individual was neither affected (iii) by the level of innate olfactory preference of the surrounding group nor (iv) by the learned olfactory preference the group was expressing. We conclude that larval Drosophila thus do not take note of specifically what surrounding larvae are doing. This implies that in a strict sense, and to the extent tested, there is no social interaction between larvae. These results validate widely used en mass approaches to the behaviour of larval Drosophila. © 2014. Published by The Company of Biologists Ltd.

  3. Insulin receptor in Drosophila melanogaster

    SciTech Connect

    Petruzzelli, L.; Herrera, R.; Rosen, O.

    1986-05-01

    A specific, high affinity insulin receptor is present in both adult Drosophila and in Drosophila embryos. Wheat germ lectin-enriched extracts of detergent-solubilized membranes from embryos and adults bind insulin with a K/sub d/ of 15 nM. Binding is specific for insulin; micromolar concentrations of proinsulin, IGFI, and IGFII are required to displace bound /sup 125/I-insulin. Insulin-dependent protein tyrosine kinase activity appears during embryogenesis. It is evident between 6 and 12 hours of development, peaks between 12 and 18 hours and falls in the adult. During 0-6 hours of embryogenesis, and in the adult, a specific protein band (Mr = 135,000) is crosslinked to /sup 125/I-insulin. During 6-12 and 12-18 hours of embryogenesis stages in which insulin-dependent protein tyrosine kinase is high, an additional band (Mr = 100,000) becomes crosslinked to /sup 125/I-insulin. Isolation and DNA sequence analysis of genomic clones encoding the Drosophila insulin receptor will be presented as will the characterization of insulin receptor mRNA's during development.

  4. Drosophila's view on insect vision.

    PubMed

    Borst, Alexander

    2009-01-13

    Within the last 400 million years, insects have radiated into at least a million species, accounting for more than half of all known living organisms: they are the most successful group in the animal kingdom, found in almost all environments of the planet, ranging in body size from a mere 0.1 mm up to half a meter. Their eyes, together with the respective parts of the nervous system dedicated to the processing of visual information, have long been the subject of intense investigation but, with the exception of some very basic reflexes, it is still not possible to link an insect's visual input to its behavioral output. Fortunately for the field, the fruit fly Drosophila is an insect, too. This genetic workhorse holds great promise for the insect vision field, offering the possibility of recording, suppressing or stimulating any single neuron in its nervous system. Here, I shall give a brief synopsis of what we currently know about insect vision, describe the genetic toolset available in Drosophila and give some recent examples of how the application of these tools have furthered our understanding of color and motion vision in Drosophila.

  5. Leigh Syndrome in Drosophila melanogaster

    PubMed Central

    Da-Rè, Caterina; von Stockum, Sophia; Biscontin, Alberto; Millino, Caterina; Cisotto, Paola; Zordan, Mauro A.; Zeviani, Massimo; Bernardi, Paolo; De Pittà, Cristiano; Costa, Rodolfo

    2014-01-01

    Leigh Syndrome (LS) is the most common early-onset, progressive mitochondrial encephalopathy usually leading to early death. The single most prevalent cause of LS is occurrence of mutations in the SURF1 gene, and LSSurf1 patients show a ubiquitous and specific decrease in the activity of mitochondrial respiratory chain complex IV (cytochrome c oxidase, COX). SURF1 encodes an inner membrane mitochondrial protein involved in COX assembly. We established a Drosophila melanogaster model of LS based on the post-transcriptional silencing of CG9943, the Drosophila homolog of SURF1. Knockdown of Surf1 was induced ubiquitously in larvae and adults, which led to lethality; in the mesodermal derivatives, which led to pupal lethality; or in the central nervous system, which allowed survival. A biochemical characterization was carried out in knockdown individuals, which revealed that larvae unexpectedly displayed defects in all complexes of the mitochondrial respiratory chain and in the F-ATP synthase, while adults had a COX-selective impairment. Silencing of Surf1 expression in Drosophila S2R+ cells led to selective loss of COX activity associated with decreased oxygen consumption and respiratory reserve. We conclude that Surf1 is essential for COX activity and mitochondrial function in D. melanogaster, thus providing a new tool that may help clarify the pathogenic mechanisms of LS. PMID:25164807

  6. Optogenetic pacing in Drosophila melanogaster

    PubMed Central

    Alex, Aneesh; Li, Airong; Tanzi, Rudolph E.; Zhou, Chao

    2015-01-01

    Electrical stimulation is currently the gold standard for cardiac pacing. However, it is invasive and nonspecific for cardiac tissues. We recently developed a noninvasive cardiac pacing technique using optogenetic tools, which are widely used in neuroscience. Optogenetic pacing of the heart provides high spatial and temporal precisions, is specific for cardiac tissues, avoids artifacts associated with electrical stimulation, and therefore promises to be a powerful tool in basic cardiac research. We demonstrated optogenetic control of heart rhythm in a well-established model organism, Drosophila melanogaster. We developed transgenic flies expressing a light-gated cation channel, channelrhodopsin-2 (ChR2), specifically in their hearts and demonstrated successful optogenetic pacing of ChR2-expressing Drosophila at different developmental stages, including the larva, pupa, and adult stages. A high-speed and ultrahigh-resolution optical coherence microscopy imaging system that is capable of providing images at a rate of 130 frames/s with axial and transverse resolutions of 1.5 and 3.9 μm, respectively, was used to noninvasively monitor Drosophila cardiac function and its response to pacing stimulation. The development of a noninvasive integrated optical pacing and imaging system provides a novel platform for performing research studies in developmental cardiology. PMID:26601299

  7. Immune stimulation reduces sleep and memory ability in Drosophila melanogaster.

    PubMed

    Mallon, Eamonn B; Alghamdi, Akram; Holdbrook, Robert T K; Rosato, Ezio

    2014-01-01

    Psychoneuroimmunology studies the increasing number of connections between neurobiology, immunology and behaviour. We demonstrate the effects of the immune response on two fundamental behaviours: sleep and memory ability in Drosophila melanogaster. We used the Geneswitch system to upregulate peptidoglycan receptor protein (PGRP) expression, thereby stimulating the immune system in the absence of infection. Geneswitch was activated by feeding the steroid RU486, to the flies. We used an aversive classical conditioning paradigm to quantify memory and measures of activity to infer sleep. Immune stimulated flies exhibited reduced levels of sleep, which could not be explained by a generalised increase in waking activity. Immune stimulated flies also showed a reduction in memory abilities. These results lend support to Drosophila as a model for immune-neural interactions and provide a possible role for sleep in the interplay between the immune response and memory.

  8. Genotoxicity of copper oxide nanoparticles in Drosophila melanogaster.

    PubMed

    Carmona, Erico R; Inostroza-Blancheteau, Claudio; Obando, Veroska; Rubio, Laura; Marcos, Ricard

    2015-09-01

    Copper oxide nanoparticles (CuONPs) are used as semiconductors, catalysts, gas sensors, and antimicrobial agents. We have used the comet and wing-spot assays in Drosophila melanogaster to assess the genotoxicity of CuONPs and ionic copper (CuSO4). Lipid peroxidation analysis was also performed (Thiobarbituric Acid Assay, TBARS). In larval hemocytes, both CuONPs and CuSO4 caused significant dose-dependent increases in DNA damage (comet assay). In the wing-spot assay, an increase in the frequency of mutant spots was observed in the wings of the adults; CuONPs were more effective than was CuSO4. Both agents induced TBARS; again, CuONPs were more active than was CuSO4. The results indicate that CuONPs are genotoxic in Drosophila, and these effects may be mediated by oxidative stress. Most of the effects appear to be related to the presence of copper ions.

  9. News Teaching: The epiSTEMe project: KS3 maths and science improvement Field trip: Pupils learn physics in a stately home Conference: ShowPhysics welcomes fun in Europe Student numbers: Physics numbers increase in UK Tournament: Physics tournament travels to Singapore Particle physics: Hadron Collider sets new record Astronomy: Take your classroom into space Forthcoming Events

    NASA Astrophysics Data System (ADS)

    2010-05-01

    Teaching: The epiSTEMe project: KS3 maths and science improvement Field trip: Pupils learn physics in a stately home Conference: ShowPhysics welcomes fun in Europe Student numbers: Physics numbers increase in UK Tournament: Physics tournament travels to Singapore Particle physics: Hadron Collider sets new record Astronomy: Take your classroom into space Forthcoming Events

  10. Male germline stem cell division and spermatocyte growth require insulin signaling in Drosophila.

    PubMed

    Ueishi, Satoru; Shimizu, Hanako; H Inoue, Yoshihiro

    2009-01-01

    Spermatogenesis in Drosophila commences with cell division of germline stem cells (GSCs) to produce male germline cells at the tip of the testis. However, molecular mechanisms inducing division of male GSCs have not been reported. Insulin-like peptides are known to play an essential role in stimulation of proliferation and growth of somatic cells, and it has recently been reported that such peptides promote cell division in female Drosophila GSCs. However, their effects on male germline cells have not been characterized. We found that inhibition of insulin production and insulin signaling mutations resulted in decreased numbers of germline cells in Drosophila testes. GSC numbers were maintained in young mutant males, with a gradual decrease in abundance of GSCs with age. Furthermore, in mutants, fewer germline cysts originated from GSCs and a lower frequency of GSC division was seen. Insulin signaling was found to promote cell cycle progression of the male GSCs at the G(2)/M phase. The cell volume of spermatocytes increases up to 25 times before initiation of meiosis in Drosophila. We examined whether insulin signaling extrinsically induces the greatest cell growth in Drosophila diploid cells and found that spermatocyte growth was affected in mutants. The results indicate that in addition to its function in somatic cells, insulin signaling plays an essential role in cell proliferation and growth during male Drosophila gametogenesis and that sperm production is regulated by hormonal control via insulin-like peptides.

  11. Drosophila Vps13 Is Required for Protein Homeostasis in the Brain

    PubMed Central

    Vonk, Jan J.; Lahaye, Liza L.; Kanon, Bart; van der Zwaag, Marianne; Velayos-Baeza, Antonio; Freire, Raimundo; van IJzendoorn, Sven C.; Grzeschik, Nicola A.; Sibon, Ody C. M.

    2017-01-01

    Chorea-Acanthocytosis is a rare, neurodegenerative disorder characterized by progressive loss of locomotor and cognitive function. It is caused by loss of function mutations in the Vacuolar Protein Sorting 13A (VPS13A) gene, which is conserved from yeast to human. The consequences of VPS13A dysfunction in the nervous system are still largely unspecified. In order to study the consequences of VPS13A protein dysfunction in the ageing central nervous system we characterized a Drosophila melanogaster Vps13 mutant line. The Drosophila Vps13 gene encoded a protein of similar size as human VPS13A. Our data suggest that Vps13 is a peripheral membrane protein located to endosomal membranes and enriched in the fly head. Vps13 mutant flies showed a shortened life span and age associated neurodegeneration. Vps13 mutant flies were sensitive to proteotoxic stress and accumulated ubiquitylated proteins. Levels of Ref(2)P, the Drosophila orthologue of p62, were increased and protein aggregates accumulated in the central nervous system. Overexpression of the human Vps13A protein in the mutant flies partly rescued apparent phenotypes. This suggests a functional conservation of human VPS13A and Drosophila Vps13. Our results demonstrate that Vps13 is essential to maintain protein homeostasis in the larval and adult Drosophila brain. Drosophila Vps13 mutants are suitable to investigate the function of Vps13 in the brain, to identify genetic enhancers and suppressors and to screen for potential therapeutic targets for Chorea-Acanthocytosis. PMID:28107480

  12. The changing biodiversity of Alabama Drosophila: important impacts of seasonal variation, urbanization, and invasive species.

    PubMed

    Bombin, Andrei; Reed, Laura K

    2016-10-01

    Global warming and anthropogenic disturbances significantly influence the biosphere, tremendously increasing species extinction rates. In Central Alabama, we analyzed Drosophilidae species composition change nearly 100 years after the previous survey. We found ten Drosophilid species that were not reported during the last major biodiversity studies, two of which are invasive pests. In addition, we analyzed the influence of seasonal environmental variables characteristic of the subtropical climate zone on Drosophila abundance and biodiversity. We found a significant correlation between temperature and abundance of total Drosophila as well as for six of the seven most represented species individually, with a maximum abundance at intermediate temperatures (18-26°C). In addition, temperature was positively correlated with biodiversity of Drosophila. Precipitation produced a significant effect on the abundance of five species of Drosophila, with different optima for each species, but did not affect overall biodiversity. We concluded that in the subtropical climate zone of Central Alabama, seasonal temperature and precipitation changes produce a significant effect on Drosophila abundance and biodiversity, while local land use also impacts fly abundance, contributing to an apparent shift in species composition over the last century. We expect global climate change and other anthropogenic factors to further impact Drosophila species composition in the subtropical climate zone into the future.

  13. Characterization of the DNA in DROSOPHILA MELANOGASTER

    PubMed Central

    Travaglini, E. C.; Petrovic, J.; Schultz, J.

    1972-01-01

    DNA has been quantitatively extracted from Drosophila melanogaster at various stages of embryonic development and analyzed by isopycnic centrifugation in CsCl and by fractionation on methylated albumin columns. The DNA is composed of three main classes of DNA, as defined by their buoyant density, ρ, in CsCl: a bulk DNA, ρ = 1.699 g cm-3, and two satellite DNAs, ρ = 1.685 g cm-3 and ρ = 1.669 g cm-3. These three types of DNA persist throughout the development of the insect. In the unfertilized egg, 80% of the total DNA consists of the satellite DNAs; this amount decreases to 18% during the first three hours after fertilization and then remains constant through embryogenesis. There is a concomitant increase of the satellite DNA's with the bulk DNA after blastoderm formation. PMID:4630028

  14. A holidic medium for Drosophila melanogaster

    PubMed Central

    Piper, Matthew DW; Blanc, Eric; Leitão-Gonçalves, Ricardo; Yang, Mingyao; He, Xiaoli; Linford, Nancy J.; Hoddinott, Matthew P; Hopfen, Corinna; Soultoukis, George A; Niemeyer, Christine; Kerr, Fiona; Pletcher, Scott D.; Ribeiro, Carlos; Partridge, Linda

    2013-01-01

    A critical requirement for research using model organisms is an appropriate, well-defined and consistent diet. There is currently no complete chemically defined (holidic) diet available for Drosophila melanogaster. We describe a holidic medium that is equal in performance to an oligidic diet optimized for adult fecundity and lifespan. It is also sufficient to support development over multiple generations, but at a reduced rate. During seven years of experiments, the holidic diet yielded more consistent experimental outcomes than oligidic food for adult fitness traits. Furthermore, nutrients and drugs are more accessible to flies in holidic medium and, similar to dietary restriction on oligidic food, amino acid dilution increases fly lifespan. We also report amino acid specific effects on food choice behavior and that folic acid from the microbiota is sufficient for development. These insights could not be gained using oligidic or meridic diets. PMID:24240321

  15. Antioxidants, metabolic rate and aging in Drosophila

    NASA Technical Reports Server (NTRS)

    Miquel, J.; Fleming, J.; Economos, A. C.

    1982-01-01

    The metabolic rate-of-living theory of aging was investigated by determining the effect of several life-prolonging antioxidants on the metabolic rate and life span of Drosophila. The respiration rate of groups of continuously agitated flies was determined in a Gilson respirometer. Vitamin E, 2,4-dinitrophenol, nordihydroguaiaretic acid, and thiazolidine carboxylic acid were employed as antioxidants. Results show that all of these antioxidants reduced the oxygen consumption rate and increased the mean life span, and a significant negative linear correlation was found between the mean life span and the metabolic rate. It is concluded that these findings indicate that some antioxidants may inhibit respiration rate in addition to their protective effect against free radical-induced cellular damage.

  16. Proliferative control in Drosophila stem cells.

    PubMed

    Kohlmaier, Alexander; Edgar, Bruce A

    2008-12-01

    The relationship between cell growth (cell mass increase over time) and cell division is poorly understood in animal stem cells. Recent studies in several Drosophila stem cell types have provided the tools to interrogate this relationship. In several cases (brat, mei-P26, pros, bam, lethal giant larvae, polo), mutations have been defined that trigger tumorous overproliferation of progenitor cells and reveal how unrestricted self-renewing capacity is controlled. Moreover, microRNAs have been discovered as essential regulators of stem cell division rate and identity, suggesting that stem cell self-renewal depends on protein translational control. Biosynthetic capacity has also been found to be limiting for stem cell division rates. Finally, asymmetric cell division can impose dominant differentiation signals in a stem cell's daughter, and this can inhibit the stem cell-specific proliferation signature and lock in cell cycle exit.

  17. Experimental Evolution and Heart Function in Drosophila.

    PubMed

    Shahrestani, Parvin; Burke, Molly K; Birse, Ryan; Kezos, James N; Ocorr, Karen; Mueller, Laurence D; Rose, Michael R; Bodmer, Rolf

    Drosophila melanogaster is a good model species for the study of heart function. However, most previous work on D. melanogaster heart function has focused on the effects of large-effect genetic variants. We compare heart function among 18 D. melanogaster populations that have been selected for altered development time, aging, or stress resistance. We find that populations with faster development and faster aging have increased heart dysfunction, measured as percentage heart failure after electrical pacing. Experimental evolution of different triglyceride levels, by contrast, has little effect on heart function. Evolved differences in heart function correlate with allele frequency changes at many loci of small effect. Genomic analysis of these populations produces a list of candidate loci that might affect cardiac function at the intersection of development, aging, and metabolic control mechanisms.

  18. Four decades of inversion polymorphism in Drosophila pseudoobscura.

    PubMed Central

    Anderson, W W; Arnold, J; Baldwin, D G; Beckenbach, A T; Brown, C J; Bryant, S H; Coyne, J A; Harshman, L G; Heed, W B; Jeffery, D E

    1991-01-01

    We report data that continue the studies of Dobzhansky and others on the frequencies of third-chromosome inversions in natural populations of Drosophila pseudoobscura in North America. The common gene arrangements continue to be present in frequencies similar to those described four decades ago, and the broad geographic patterns also remain unchanged. There is only one pronounced trend over time: the increase in frequency of the Tree Line inversion in Pacific coast populations. PMID:1946458

  19. Penelope retroelements from Drosophila virilis are active after transformation of Drosophila melanogaster

    PubMed Central

    Pyatkov, Konstantin I.; Shostak, Natalia G.; Zelentsova, Elena S.; Lyozin, George T.; Melekhin, Michael I.; Finnegan, David J.; Kidwell, Margaret G.; Evgen'ev, Michael B.

    2002-01-01

    The Penelope family of retroelements was first described in species of the Drosophila virilis group. Intact elements encode a reverse transcriptase and an endonuclease of the UvrC type, which may play a role in Penelope integration. Penelope is a key element in the induction of D. virilis hybrid dysgenesis, which involves the mobilization of several unrelated families of transposable elements. We here report the successful introduction of Penelope into the germ line of Drosophila melanogaster by P element-mediated transformation with three different constructs. Penelope is actively transcribed in the D. melanogaster genome only in lines transformed with a construct containing a full-length Penelope clone. The transcript is identical to that detected in D. virilis dysgenic hybrids. Most newly transposed Penelope elements have a very complex organization. Significant proliferation of Penelope copy number occurred in some lines during the 24-month period after transformation. The absence of copy number increase with two other constructs suggests that the 5′ and/or 3′ UTRs of Penelope are required for successful transposition in D. melanogaster. No insect retroelement has previously been reported to be actively transcribed and to increase in copy number after interspecific transformation. PMID:12451171

  20. Modeling Spinal Muscular Atrophy in Drosophila

    PubMed Central

    Mukherjee, Ashim; Kankel, Mark W.; Sen, Anindya; Sridhar, Vasanthi; Fulga, Tudor A.; Hart, Anne C.; Van Vactor, David; Artavanis-Tsakonas, Spyros

    2008-01-01

    Spinal Muscular Atrophy (SMA), a recessive hereditary neurodegenerative disease in humans, has been linked to mutations in the survival motor neuron (SMN) gene. SMA patients display early onset lethality coupled with motor neuron loss and skeletal muscle atrophy. We used Drosophila, which encodes a single SMN ortholog, survival motor neuron (Smn), to model SMA, since reduction of Smn function leads to defects that mimic the SMA pathology in humans. Here we show that a normal neuromuscular junction (NMJ) structure depends on SMN expression and that SMN concentrates in the post-synaptic NMJ regions. We conducted a screen for genetic modifiers of an Smn phenotype using the Exelixis collection of transposon-induced mutations, which affects approximately 50% of the Drosophila genome. This screen resulted in the recovery of 27 modifiers, thereby expanding the genetic circuitry of Smn to include several genes not previously known to be associated with this locus. Among the identified modifiers was wishful thinking (wit), a type II BMP receptor, which was shown to alter the Smn NMJ phenotype. Further characterization of two additional members of the BMP signaling pathway, Mothers against dpp (Mad) and Daughters against dpp (Dad), also modify the Smn NMJ phenotype. The NMJ defects caused by loss of Smn function can be ameliorated by increasing BMP signals, suggesting that increased BMP activity in SMA patients may help to alleviate symptoms of the disease. These results confirm that our genetic approach is likely to identify bona fide modulators of SMN activity, especially regarding its role at the neuromuscular junction, and as a consequence, may identify putative SMA therapeutic targets. PMID:18791638

  1. Drosophila and Beer: An Experimental Laboratory Exercise

    ERIC Educational Resources Information Center

    Kurvink, Karen

    2004-01-01

    Drosophila melanogaster is a popular organism for studying genetics and development. Maintaining Drosophila on medium prepared with varying concentrations of beer and evaluating the effects on reproduction, life cycle stages and other factors is one of the exercises that is versatile and applicable to many student levels.

  2. Using Drosophila for Studies of Intermediate Filaments.

    PubMed

    Bohnekamp, Jens; Cryderman, Diane E; Thiemann, Dylan A; Magin, Thomas M; Wallrath, Lori L

    2016-01-01

    Drosophila melanogaster is a useful organism for determining protein function and modeling human disease. Drosophila offers a rapid generation time and an abundance of genomic resources and genetic tools. Conservation in protein structure, signaling pathways, and developmental processes make studies performed in Drosophila relevant to other species, including humans. Drosophila models have been generated for neurodegenerative diseases, muscular dystrophy, cancer, and many other disorders. Recently, intermediate filament protein diseases have been modeled in Drosophila. These models have revealed novel mechanisms of pathology, illuminated potential new routes of therapy, and make whole organism compound screens feasible. The goal of this chapter is to outline steps to study intermediate filament function and model intermediate filament-associated diseases in Drosophila. The steps are general and can be applied to study the function of almost any protein. The protocols outlined here are for both the novice and experienced Drosophila researcher, allowing the rich developmental and cell biology that Drosophila offers to be applied to studies of intermediate filaments. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Drosophila and Beer: An Experimental Laboratory Exercise

    ERIC Educational Resources Information Center

    Kurvink, Karen

    2004-01-01

    Drosophila melanogaster is a popular organism for studying genetics and development. Maintaining Drosophila on medium prepared with varying concentrations of beer and evaluating the effects on reproduction, life cycle stages and other factors is one of the exercises that is versatile and applicable to many student levels.

  4. Further characterization of the Odysseus locus of hybrid sterility in Drosophila: one gene is not enough.

    PubMed

    Perez, D E; Wu, C I

    1995-05-01

    Previously we mapped by genetical and molecular means a gene that contributes to hybrid-male sterility between Drosophila mauritiana and D. simulans to the cytological interval of 16D. In this report, we refine the mapping of this gene, Odysseus (Ods) and show that it can be delineated to a region the size of an average gene. We further demonstrate that, while Ods appears to be a discrete element, it requires other nearby gene(s) to be cointrogressed to confer full hybrid sterility effect. This observation is in agreement with the view that reproductive isolation between closely related species of Drosophila is usually caused by several genes of weak effect from the same species that interact strongly among themselves as well as with the foreign genetic background.

  5. Differential response of DDT susceptible and resistant Drosophila melanogaster strains to DDT and oxidative stress

    USDA-ARS?s Scientific Manuscript database

    Metabolic DDT resistance in Drosophila melanogaster is associated with increased cytochrome P450 expression. Increased P450 activity is also associated with increased oxidative stress. In contrast, increased glutathione S transferase (GST) expression has been associated with a greater ability of o...

  6. FMRFamide signaling promotes stress-induced sleep in Drosophila

    PubMed Central

    Lenz, Olivia; Xiong, Jianmei; Nelson, Matthew D.; Raizen, David M.; Williams, Julie A.

    2015-01-01

    Enhanced sleep in response to cellular stress is a conserved adaptive behavior across multiple species, but the mechanism of this process is poorly understood. Drosophila melanogaster increases sleep following exposure to septic or aseptic injury, and Caenorhabditis elegans displays sleep-like quiescence following exposure to high temperatures that stress cells. We show here that, similar to C. elegans, Drosophila responds to heat stress with an increase in sleep. In contrast to Drosophila infection-induced sleep, heat-induced sleep is not sensitive to the time-of-day of the heat pulse. Moreover, the sleep response to heat stress does not require Relish, the NFκB transcription factor that is necessary for infection-induced sleep, indicating that sleep is induced by multiple mechanisms from different stress modalities. We identify a sleep-regulating role for a signaling pathway involving FMRFamide neuropeptides and their receptor FR. Animals mutant for either FMRFamide or for the FMRFamide receptor (FR) have a reduced recovery sleep in response to heat stress. FR mutants, in addition, show reduced sleep responses following infection with Serratia marcescens, and succumb to infection at a faster rate than wild-type controls. Together, these findings support the hypothesis that FMRFamide and its receptor promote an adaptive increase in sleep following stress. Because an FMRFamide-like neuropeptide plays a similar role in C. elegans, we propose that FRMFamide neuropeptide signaling is an ancient regulator of recovery sleep which occurs in response to cellular stress. PMID:25668617

  7. FMRFamide signaling promotes stress-induced sleep in Drosophila.

    PubMed

    Lenz, Olivia; Xiong, Jianmei; Nelson, Matthew D; Raizen, David M; Williams, Julie A

    2015-07-01

    Enhanced sleep in response to cellular stress is a conserved adaptive behavior across multiple species, but the mechanism of this process is poorly understood. Drosophila melanogaster increases sleep following exposure to septic or aseptic injury, and Caenorhabditis elegans displays sleep-like quiescence following exposure to high temperatures that stress cells. We show here that, similar to C. elegans, Drosophila responds to heat stress with an increase in sleep. In contrast to Drosophila infection-induced sleep, heat-induced sleep is not sensitive to the time-of-day of the heat pulse. Moreover, the sleep response to heat stress does not require Relish, the NFκB transcription factor that is necessary for infection-induced sleep, indicating that sleep is induced by multiple mechanisms from different stress modalities. We identify a sleep-regulating role for a signaling pathway involving FMRFamide neuropeptides and their receptor FR. Animals mutant for either FMRFamide or for the FMRFamide receptor (FR) have a reduced recovery sleep in response to heat stress. FR mutants, in addition, show reduced sleep responses following infection with Serratia marcescens, and succumb to infection at a faster rate than wild-type controls. Together, these findings support the hypothesis that FMRFamide and its receptor promote an adaptive increase in sleep following stress. Because an FMRFamide-like neuropeptide plays a similar role in C. elegans, we propose that FRMFamide neuropeptide signaling is an ancient regulator of recovery sleep which occurs in response to cellular stress.

  8. The impact of host diet on Wolbachia titer in Drosophila.

    PubMed

    Serbus, Laura R; White, Pamela M; Silva, Jessica Pintado; Rabe, Amanda; Teixeira, Luis; Albertson, Roger; Sullivan, William

    2015-03-01

    While a number of studies have identified host factors that influence endosymbiont titer, little is known concerning environmental influences on titer. Here we examined nutrient impact on maternally transmitted Wolbachia endosymbionts in Drosophila. We demonstrate that Drosophila reared on sucrose- and yeast-enriched diets exhibit increased and reduced Wolbachia titers in oogenesis, respectively. The yeast-induced Wolbachia depletion is mediated in large part by the somatic TOR and insulin signaling pathways. Disrupting TORC1 with the small molecule rapamycin dramatically increases oocyte Wolbachia titer, whereas hyper-activating somatic TORC1 suppresses oocyte titer. Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer. Exposure to yeast-enriched diets altered Wolbachia nucleoid morphology in oogenesis. Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system. These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer.

  9. The Impact of Host Diet on Wolbachia Titer in Drosophila

    PubMed Central

    Serbus, Laura R.; White, Pamela M.; Silva, Jessica Pintado; Rabe, Amanda; Teixeira, Luis; Albertson, Roger; Sullivan, William

    2015-01-01

    While a number of studies have identified host factors that influence endosymbiont titer, little is known concerning environmental influences on titer. Here we examined nutrient impact on maternally transmitted Wolbachia endosymbionts in Drosophila. We demonstrate that Drosophila reared on sucrose- and yeast-enriched diets exhibit increased and reduced Wolbachia titers in oogenesis, respectively. The yeast-induced Wolbachia depletion is mediated in large part by the somatic TOR and insulin signaling pathways. Disrupting TORC1 with the small molecule rapamycin dramatically increases oocyte Wolbachia titer, whereas hyper-activating somatic TORC1 suppresses oocyte titer. Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer. Exposure to yeast-enriched diets altered Wolbachia nucleoid morphology in oogenesis. Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system. These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer. PMID:25826386

  10. Copper homoeostasis in Drosophila melanogaster S2 cells

    PubMed Central

    2004-01-01

    Copper homoeostasis was investigated in the Drosophila melanogaster S2 cell line to develop an insect model for the study of copper regulation. Real-time PCR studies have demonstrated expression in S2 cells of putative orthologues of human Cu regulatory genes involved in the uptake, transport, sequestration and efflux of Cu. Drosophila orthologues of the mammalian Cu chaperones, ATOX1 (a human orthologue of yeast ATX1), CCS (copper chaperone for superoxide dismutase), COX17 (a human orthologue of yeast COX17), and SCO1 and SCO2, did not significantly respond transcriptionally to increased Cu levels, whereas MtnA, MtnB and MtnD (Drosophila orthologues of human metallothioneins) were up-regulated by Cu in a time- and dose-dependent manner. To examine the effect on Cu homoeostasis, expression of several key copper homoeostasis genes was suppressed using double-stranded RNA interference. Suppression of the MTF-1 (metal-regulatory transcription factor 1), reduced both basal and Cu-induced gene expressions of MtnA, MtnB and MtnD, significantly reducing the tolerance of these cells to increased Cu. Suppression of either Ctr1A (a Drosophila orthologue of yeast CTR1) or Ctr1B significantly reduced Cu uptake from media, demonstrating that both these proteins function to transport Cu into S2 cells. Significantly, Cu induced Ctr1B gene expression, and this could be prevented by suppressing MTF-1, suggesting that Ctr1B might be involved in Cu detoxification. Suppression of DmATP7, the putative homologue of human Cu transporter genes ATP7A and ATP7B, significantly increased Cu accumulation, demonstrating that DmATP7 is essential for efflux of excess Cu. This work is consistent with previous studies in mammalian cells, validating S2 cells as a model system for studying Cu transport and identifying novel Cu regulatory mechanisms. PMID:15239669

  11. The benefits of male ejaculate sex peptide transfer in Drosophila melanogaster.

    PubMed

    Fricke, C; Wigby, S; Hobbs, R; Chapman, T

    2009-02-01

    The accessory gland protein (Acp) ejaculate molecules of male Drosophila melanogaster mediate sexual selection and sexual conflict at the molecular level. However, to date no studies have comprehensively measured the timing and magnitude of fitness benefits to males of transferring specific Acps. This is an important omission because without this information it is not possible to fully understand the strength and form of selection acting on adaptations such as Acps. Here, we measured the fitness benefits to males of ejaculate sex peptide (SP) transfer. SP is of interest because it is a candidate for mediating sexual conflict: its frequent receipt reduces female fitness. In single matings with virgin females SP is known to increase egg laying and decrease receptivity. Hence, we predicted that SP could: (i) boost a male's absolute paternity by increasing offspring production and delaying female remating and/or (ii) boost relative paternity share. We tested these predictions using two different lines of SP-lacking males, in both two-mating and free-mating assay conditions. SP transfer conferred higher absolute, but not relative, male reproductive success. In matings with virgin females, SP transfer increased mating productivity and delayed remating and hence the onset of sperm competition. In already mated females, SP transfer did not elevate absolute progeny production, but did increase intermating intervals and hence the period over which a male could gain paternity. Consistent with this, under free-mating conditions over an extended period, we detected a 'per-mating' fitness benefit for males transferring SP. These benefits are consistent with a role for SP in mediating conflict, with SP acting to maximize short-term fitness benefits for males.

  12. 47 CFR 1.248 - Prehearing conferences; hearing conferences.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Prehearing conferences; hearing conferences. 1... Hearing Proceedings Prehearing Procedures § 1.248 Prehearing conferences; hearing conferences. (a) The... to appear at a specified time and place for a conference prior to a hearing, or to submit...

  13. Unraveling the Neurobiology of Sleep and Sleep Disorders Using Drosophila.

    PubMed

    Chakravarti, L; Moscato, E H; Kayser, M S

    2017-01-01

    Sleep disorders in humans are increasingly appreciated to be not only widespread but also detrimental to multiple facets of physical and mental health. Recent work has begun to shed light on the mechanistic basis of sleep disorders like insomnia, restless legs syndrome, narcolepsy, and a host of others, but a more detailed genetic and molecular understanding of how sleep goes awry is lacking. Over the past 15 years, studies in Drosophila have yielded new insights into basic questions regarding sleep function and regulation. More recently, powerful genetic approaches in the fly have been applied toward studying primary human sleep disorders and other disease states associated with dysregulated sleep. In this review, we discuss the contribution of Drosophila to the landscape of sleep biology, examining not only fundamental advances in sleep neurobiology but also how flies have begun to inform pathological sleep states in humans. © 2017 Elsevier Inc. All rights reserved.

  14. Dynamic hyper-editing underlies temperature adaptation in Drosophila

    PubMed Central

    Ashwal-Fluss, Reut; Pandey, Varun; Levanon, Erez Y.; Kadener, Sebastian

    2017-01-01

    In Drosophila, A-to-I editing is prevalent in the brain, and mutations in the editing enzyme ADAR correlate with specific behavioral defects. Here we demonstrate a role for ADAR in behavioral temperature adaptation in Drosophila. Although there is a higher level of editing at lower temperatures, at 29°C more sites are edited. These sites are less evolutionarily conserved, more disperse, less likely to be involved in secondary structures, and more likely to be located in exons. Interestingly, hypomorph mutants for ADAR display a weaker transcriptional response to temperature changes than wild-type flies and a highly abnormal behavioral response upon temperature increase. In sum, our data shows that ADAR is essential for proper temperature adaptation, a key behavior trait that is essential for survival of flies in the wild. Moreover, our results suggest a more general role of ADAR in regulating RNA secondary structures in vivo. PMID:28746393

  15. Electron spin changes during general anesthesia in Drosophila

    PubMed Central

    Turin, Luca; Skoulakis, Efthimios M. C.; Horsfield, Andrew P.

    2014-01-01

    We show that the general anesthetics xenon, sulfur hexafluoride, nitrous oxide, and chloroform cause rapid increases of different magnitude and time course in the electron spin content of Drosophila. With the exception of CHCl3, these changes are reversible. Anesthetic-resistant mutant strains of Drosophila exhibit a different pattern of spin responses to anesthetic. In two such mutants, the spin response to CHCl3 is absent. We propose that these spin changes are caused by perturbation of the electronic structure of proteins by general anesthetics. Using density functional theory, we show that general anesthetics perturb and extend the highest occupied molecular orbital of a nine-residue α-helix. The calculated perturbations are qualitatively in accord with the Meyer–Overton relationship and some of its exceptions. We conclude that there may be a connection between spin, electron currents in cells, and the functioning of the nervous system. PMID:25114249

  16. A Drosophila Model of High Sugar Diet-Induced Cardiomyopathy

    PubMed Central

    Na, Jianbo; Musselman, Laura Palanker; Pendse, Jay; Baranski, Thomas J.; Bodmer, Rolf; Ocorr, Karen; Cagan, Ross

    2013-01-01

    Diets high in carbohydrates have long been linked to progressive heart dysfunction, yet the mechanisms by which chronic high sugar leads to heart failure remain poorly understood. Here we combine diet, genetics, and physiology to establish an adult Drosophila melanogaster model of chronic high sugar-induced heart disease. We demonstrate deterioration of heart function accompanied by fibrosis-like collagen accumulation, insulin signaling defects, and fat accumulation. The result was a shorter life span that was more severe in the presence of reduced insulin and P38 signaling. We provide evidence of a role for hexosamine flux, a metabolic pathway accessed by glucose. Increased hexosamine flux led to heart function defects and structural damage; conversely, cardiac-specific reduction of pathway activity prevented sugar-induced heart dysfunction. Our data establish Drosophila as a useful system for exploring specific aspects of diet-induced heart dysfunction and emphasize enzymes within the hexosamine biosynthetic pathway as candidate therapeutic targets. PMID:23326243

  17. [Ecological imprinting and protein biosynthesis. Experiments with Drosophila melanogaster Meigen].

    PubMed

    Laudien, H; Iken, H H

    1977-06-01

    According to the "host selection principle", butterflies and other herbivorous insects preferentially lay their eggs on those plant races that they fed on when young. This is also true for karpophagic and parasitic insects. The selection of specific chemical conditions could be either inherited or acquired. If learned information determines host selection, we have a case of imprinting, as a) reception and use of the information are not simultaneous, b) there is no reward. In experiments with Drosophila melanogaster we marked the egg deposition medium with ethanol, acetic acid, peppermint oil, or benzaldehyd. The flies spontaneously prefer mediums with ethanol and acetic acid, and reject peppermint oil and benzaldehyd. If they are reared in one of these media, the preference for it is increased, or the rejection rate lowered. Rearing with actinomycin C neutralizes the effect of the other markers. It is concluded that actinomycin C blocks imprinting on the egg deposition substrate in Drosophila melanogaster.

  18. Dynamic hyper-editing underlies temperature adaptation in Drosophila.

    PubMed

    Buchumenski, Ilana; Bartok, Osnat; Ashwal-Fluss, Reut; Pandey, Varun; Porath, Hagit T; Levanon, Erez Y; Kadener, Sebastian

    2017-07-01

    In Drosophila, A-to-I editing is prevalent in the brain, and mutations in the editing enzyme ADAR correlate with specific behavioral defects. Here we demonstrate a role for ADAR in behavioral temperature adaptation in Drosophila. Although there is a higher level of editing at lower temperatures, at 29°C more sites are edited. These sites are less evolutionarily conserved, more disperse, less likely to be involved in secondary structures, and more likely to be located in exons. Interestingly, hypomorph mutants for ADAR display a weaker transcriptional response to temperature changes than wild-type flies and a highly abnormal behavioral response upon temperature increase. In sum, our data shows that ADAR is essential for proper temperature adaptation, a key behavior trait that is essential for survival of flies in the wild. Moreover, our results suggest a more general role of ADAR in regulating RNA secondary structures in vivo.

  19. Temporal Stability of Molecular Diversity Measures in Natural Populations of Drosophila pseudoobscura and Drosophila persimilis

    PubMed Central

    Hish, Alexander J.; Noor, Mohamed A. F.

    2015-01-01

    Many molecular ecological and evolutionary studies sample wild populations at a single point in time, but that data represents genetic variation from a potentially unrepresentative snapshot in time. Variation across time in genetic parameters may occur quickly in species that produce multiple generations of offspring per year. Here, we compare genetic diversity in wild caught populations of Drosophila persimilis and Drosophila pseudoobscura collected 16 years apart at the same time of year and same site at 4 X-linked and 2 mitochondrial loci to assess genetic stability. We found no major changes in nucleotide diversity in either species, but we observed a drastic shift in Tajima’s D between D. pseudoobscura timepoints at 1 locus associated with increased abundance of a set of related haplotypes. Our data also suggests that D. persimilis may have recently accelerated its demographic expansion. While the changes we observed were modest, this study reinforces the importance of considering potential temporal variation in genetic parameters within single populations over short evolutionary timescales. PMID:25969560

  20. GE STEM Teacher's Conference

    NASA Image and Video Library

    2017-07-13

    Teachers participate in the Rocketry Engineering Design Challenge during the 2017 GE Foundation High School STEM Integration Conference at the Center for Space Education at NASA's Kennedy Space Center. High school teachers from across the country took part in the week-long conference, which is designed to explore effective ways for teachers, schools and districts from across the country to integrate STEM throughout the curriculum. The conference is a partnership between GE Foundation and the National Science Teachers Association.

  1. Host plant-driven sensory specialization in Drosophila erecta

    PubMed Central

    Linz, Jeanine; Baschwitz, Amelie; Strutz, Antonia; Dweck, Hany K. M.; Sachse, Silke; Hansson, Bill S.; Stensmyr, Marcus C.

    2013-01-01

    Finding appropriate feeding and breeding sites is crucial for all insects. To fulfil this vital task, many insects rely on their sense of smell. Alterations in the habitat—or in lifestyle—should accordingly also be reflected in the olfactory system. Solid functional evidence for direct adaptations in the olfactory system is however scarce. We have, therefore, examined the sense of smell of Drosophila erecta, a close relative of Drosophila melanogaster and specialist on screw pine fruits (Pandanus spp.). In comparison with three sympatric sibling species, D. erecta shows specific alterations in its olfactory system towards detection and processing of a characteristic Pandanus volatile (3-methyl-2-butenyl acetate, 3M2BA). We show that D. erecta is more sensitive towards this substance, and that the increased sensitivity derives from a numerical increase of one olfactory sensory neuron (OSN) class. We also show that axons from these OSNs form a complex of enlarged glomeruli in the antennal lobe, the first olfactory brain centre, of D. erecta. Finally, we show that 3M2BA induces oviposition in D. erecta, but not in D. melanogaster. The presumed adaptations observed here follow to a remarkable degree those found in Drosophila sechellia, a specialist upon noni fruit, and suggest a general principle for how specialization affects the sense of smell. PMID:23595274

  2. Increasing Rural Adults' Participation in Collegial Programs: Exemplary Programs. Proceedings of the Rural Action Conference "Programs and Activities to Overcome Barriers to Rural Adult Participation in Postsecondary Education" (Blacksburg, Virginia, June 1-3, 1987).

    ERIC Educational Resources Information Center

    Sullins, W. Robert, Ed.; And Others

    Approximately 85 educators from six states participated in a regional conference designed to showcase exemplary and collaborative programs to overcome many of the barriers faced by rural adults in pursuing higher education. After the keynote address, "The Role of Adult Learning in Revitalizing Rural Communities," by Cornelia Butler Flora, the…

  3. Increasing the Options for Wholesome Peer Level Experiences Across Racial, Cultural, and Economic Lines; Highlights of the Eighth National Conference on Equal Educational Opportunity, Washington, D.C., February 19-21, 1970.

    ERIC Educational Resources Information Center

    Kepecs, Mary, Ed.; Ross, Ellen, Ed.

    This booklet is comprised of summaries of contributions to the Eighth National Conference on Equal Educational Opportunity. National Education Association President, George Fischer, expresses views about changing attitudes, cultural differences, Southern school desegregation, busing, and the Nixon administration. Mrs. LaDonna Harris, a Comanche…

  4. Does interspecific hybridization influence evolutionary rates? An experimental study of laboratory adaptation in hybrids between Drosophila serrata and Drosophila birchii.

    PubMed Central

    Hercus, M J; Hoffmann, A A

    1999-01-01

    The low initial fitness of progeny from interspecific crosses in animals and the rarity of interspecific hybridization in natural environments have led to a debate about the evolutionary importance of this phenomenon. Here we directly assess the effects of hybridization between Drosophila serrata and Drosophila birchii on evolutionary rates. We looked at the effects on laboratory adaptation over 30 generations in two laboratory environments, one of which involved nutrition and temperature stress. Laboratory adaptation occurred over time in both environments as reflected by a marked change in viability. However, whilst hybrid lines at no stage performed poorly relative to parental lines, their rate of adaptation never exceeded that of the parentals. Thus, there was no evidence that hybridization increased evolutionary rates. Instead, hybrid lines converged phenotypically with one of the parental species. PMID:10649634

  5. Chromosome Conformation Capture in Drosophila.

    PubMed

    Li, Hua-Bing

    2016-01-01

    Linear chromatin fiber is packed inside the nuclei as a complex three-dimensional structure, and the organization of the chromatin has important roles in the appropriate spatial and temporal regulation of gene expression. To understand how chromatin organizes inside nuclei, and how regulatory proteins physically interact with genes, chromosome conformation capture (3C) technique provides a powerful and sensitive tool to detect both short- and long-range DNA-DNA interaction. Here I describe the 3C technique to detect the DNA-DNA interactions mediated by insulator proteins that are closely related to PcG in Drosophila, which is also broadly applicable to other systems.

  6. Cryobiological preservation of Drosophila embryos

    SciTech Connect

    Mazur, P.; Schreuders, P.D.; Cole, K.W.; Hall, J.W. ); Mahowald, A.P. )

    1992-12-18

    The inability to cryobiologically preserve the fruit fly Drosophila melanogaster has required that fly stocks be maintained by frequent transfer of adults. This method is costly in terms of time and can lead to loss of stocks. Traditional slow freezing methods do not succeed because the embryos are highly sensitive to chilling. With the procedures described here, 68 percent of precisely staged 15-hour Oregon R (wild-type) embryos hatch after vitrification at -205[degree]C, and 40 percent of the resulting larvae develop into normal adult flies. These embryos are among the most complex organisms successfully preserved by cryobiology.

  7. The molecular basis of CO2 reception in Drosophila

    PubMed Central

    Kwon, Jae Young; Dahanukar, Anupama; Weiss, Linnea A.; Carlson, John R.

    2007-01-01

    CO2 elicits a response from many insects, including mosquito vectors of diseases such as malaria and yellow fever, but the molecular basis of CO2 detection is unknown in insects or other higher eukaryotes. Here we show that Gr21a and Gr63a, members of a large family of Drosophila seven-transmembrane-domain chemoreceptor genes, are coexpressed in chemosensory neurons of both the larva and the adult. The two genes confer CO2 response when coexpressed in an in vivo expression system, the “empty neuron system.” The response is highly specific for CO2 and dependent on CO2 concentration. The response shows an equivalent dependence on the dose of Gr21a and Gr63a. None of 39 other chemosensory receptors confers a comparable response to CO2. The identification of these receptors may now allow the identification of agents that block or activate them. Such agents could affect the responses of insect pests to the humans they seek. PMID:17360684

  8. Genetic human prion disease modelled in PrP transgenic Drosophila

    PubMed Central

    Thackray, Alana M.; Cardova, Alzbeta; Wolf, Hanna; Pradl, Lydia; Vorberg, Ina; Jackson, Walker S.

    2017-01-01

    Inherited human prion diseases, such as fatal familial insomnia (FFI) and familial Creutzfeldt–Jakob disease (fCJD), are associated with autosomal dominant mutations in the human prion protein gene PRNP and accumulation of PrPSc, an abnormal isomer of the normal host protein PrPC, in the brain of affected individuals. PrPSc is the principal component of the transmissible neurotoxic prion agent. It is important to identify molecular pathways and cellular processes that regulate prion formation and prion-induced neurotoxicity. This will allow identification of possible therapeutic interventions for individuals with, or at risk from, genetic human prion disease. Increasingly, Drosophila has been used to model human neurodegenerative disease. An important unanswered question is whether genetic prion disease with concomitant spontaneous prion formation can be modelled in Drosophila. We have used pUAST/PhiC31-mediated site-directed mutagenesis to generate Drosophila transgenic for murine or hamster PrP (prion protein) that carry single-codon mutations associated with genetic human prion disease. Mouse or hamster PrP harbouring an FFI (D178N) or fCJD (E200K) mutation showed mild Proteinase K resistance when expressed in Drosophila. Adult Drosophila transgenic for FFI or fCJD variants of mouse or hamster PrP displayed a spontaneous decline in locomotor ability that increased in severity as the flies aged. Significantly, this mutant PrP-mediated neurotoxic fly phenotype was transferable to recipient Drosophila that expressed the wild-type form of the transgene. Collectively, our novel data are indicative of the spontaneous formation of a PrP-dependent neurotoxic phenotype in FFI- or CJD-PrP transgenic Drosophila and show that inherited human prion disease can be modelled in this invertebrate host. PMID:28814578

  9. Drosophila as an unconventional substrate for microfabrication

    NASA Astrophysics Data System (ADS)

    Shum, Angela J.; Parviz, Babak A.

    2007-02-01

    We present the application of Drosophila fruit flies as an unconventional substrate for microfabrication. Drosophila by itself represents a complex system capable of many functions not attainable with current microfabrication technology. By using Drosophila as a substrate, we are able to capitalize on these natural functions while incorporating additional functionality into a superior hybrid system. In the following, development of microfabrication processes for Drosophila substrates is discussed. In particular, results of a study on Drosophila tolerance to vacuum pressure during multiple stages of development are given. A remarkable finding that adult Drosophila may withstand up to 3 hours of exposure to vacuum with measurable survival is noted. This finding opens a number of new opportunities for performing fabrication processes, similar to the ones performed on a silicon wafer, on a fruit fly as a live substrate. As a model microfabrication process, it is shown how a collection of Drosophila can be made to self-assemble into an array of microfabricated recesses on a silicon wafer and how a shadow mask can be used to thermally evaporate 100 nm of indium on flies. The procedure resulted in the production of a number of live flies with a pre-designed metal micropattern on their wings. This demonstration of vacuum microfabrication on a live organism provides the first step towards the development of a hybrid biological/solid-state manufacturing process for complex microsystems.

  10. 76 FR 64083 - Reliability Technical Conference; Notice of Technical Conference

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Reliability Technical Conference; Notice of Technical Conference Take notice that the Federal Energy Regulatory Commission will hold a Technical Conference on Tuesday, November...

  11. Alcohol resistance in Drosophila is modulated by the Toll innate immune pathway.

    PubMed

    Troutwine, B R; Ghezzi, A; Pietrzykowski, A Z; Atkinson, N S

    2016-04-01

    A growing body of evidence has shown that alcohol alters the activity of the innate immune system and that changes in innate immune system activity can influence alcohol-related behaviors. Here, we show that the Toll innate immune signaling pathway modulates the level of alcohol resistance in Drosophila. In humans, a low level of response to alcohol is correlated with increased risk of developing an alcohol use disorder. The Toll signaling pathway was originally discovered in, and has been extensively studied in Drosophila. The Toll pathway is a major regulator of innate immunity in Drosophila, and mammalian Toll-like receptor signaling has been implicated in alcohol responses. Here, we use Drosophila-specific genetic tools to test eight genes in the Toll signaling pathway for effects on the level of response to ethanol. We show that increasing the activity of the pathway increases ethanol resistance whereas decreasing the pathway activity reduces ethanol resistance. Furthermore, we show that gene products known to be outputs of innate immune signaling are rapidly induced following ethanol exposure. The interaction between the Toll signaling pathway and ethanol is rooted in the natural history of Drosophila melanogaster.

  12. Alcohol resistance in Drosophila is modulated by the Toll innate immune pathway

    PubMed Central

    Troutwine, Benjamin R.; Ghezzi, Alfredo; Pietrzykowski, Andrzej Z.; Atkinson, Nigel S.

    2016-01-01

    A growing body of evidence has shown that alcohol alters the activity of the innate immune system and that changes in innate immune system activity can influence alcohol-related behaviors (Cui et al., 2014; Vetreno & Crews, 2014). Here we show that the Toll innate immune signaling pathway modulates the level of alcohol resistance in Drosophila. In humans, a low level of response to alcohol is correlated with increased risk of developing an alcohol use disorder (Schuckit, 1994). The Toll signaling pathway was originally discovered in, and has been extensively studied in Drosophila. The Toll pathway is a major regulator of innate immunity in Drosophila, and mammalian Toll-like receptor signaling has been implicated in alcohol responses. Here, we use Drosophila-specific genetic tools to test eight genes in the Toll signaling pathway for effects on the level of response to ethanol. We show that increasing the activity of the pathway increases ethanol resistance while decreasing pathway activity reduces ethanol resistance. Furthermore, we show that gene products known to be outputs of innate immune signaling are rapidly induced following ethanol exposure. The interaction between the Toll signaling pathway and ethanol is rooted in the natural history of Drosophila melanogaster. PMID:26916032

  13. Expression of the Retrotransposon Helena Reveals a Complex Pattern of TE Deregulation in Drosophila Hybrids

    PubMed Central

    Romero-Soriano, Valèria; Garcia Guerreiro, Maria Pilar

    2016-01-01

    Transposable elements (TEs), repeated mobile sequences, are ubiquitous in the eukaryotic kingdom. Their mobilizing capacity confers on them a high mutagenic potential, which must be strongly regulated to guarantee genome stability. In the Drosophila germline, a small RNA-mediated silencing system, the piRNA (Piwi-interacting RNA) pathway, is the main responsible TE regulating mechanism, but some stressful conditions can destabilize it. For instance, during interspecific hybridization, genomic stress caused by the shock of two different genomes can lead, in both animals and plants, to higher transposition rates. A recent study in D. buzatii—D. koepferae hybrids detected mobilization of 28 TEs, yet little is known about the molecular mechanisms explaining this transposition release. We have characterized one of the mobilized TEs, the retrotransposon Helena, and used quantitative expression to assess whether its high transposition rates in hybrids are preceded by increased expression. We have also localized Helena expression in the gonads to see if cellular expression patterns have changed in the hybrids. To give more insight into changes in TE regulation in hybrids, we analysed Helena-specific piRNA populations of hybrids and parental species. Helena expression is not globally altered in somatic tissues, but male and female gonads have different patterns of deregulation. In testes, Helena is repressed in F1, increasing then its expression up to parental values. This is linked with a mislocation of Helena transcripts along with an increase of their specific piRNA levels. Ovaries have additive levels of Helena expression, but the ping-pong cycle efficiency seems to be reduced in F1 hybrids. This could be at the origin of new Helena insertions in hybrids, which would be transmitted to F1 hybrid female progeny. PMID:26812285

  14. Sleep restores behavioral plasticity to Drosophila mutants

    PubMed Central

    Dissel, Stephane; Angadi, Veena; Kirszenblat, Leonie; Suzuki, Yasuko; Donlea, Jeff; Klose, Markus; Koch, Zachary; English, Denis; Winsky-Sommerer, Raphaelle; van Swinderen, Bruno; Shaw, Paul J.

    2015-01-01

    SUMMARY Given the role that sleep plays in modulating plasticity, we hypothesized that increasing sleep would restore memory to canonical memory mutants without specifically rescuing the causal molecular-lesion. Sleep was increased using three independent strategies: activating the dorsal Fan Shaped Body (FB), increasing the expression of Fatty acid binding protein (dFabp) or by administering the GABA-A agonist 4,5,6,7-tetrahydroisoxazolo-[5,4-c]pyridine-3-ol (THIP). Short-term memory (STM) or Long-term memory (LTM) was evaluated in rutabaga (rut) and dunce (dnc) mutants using Aversive Phototaxic Suppression (APS) and courtship conditioning. Each of the three independent strategies increased sleep and restored memory to rut and dnc mutants. Importantly, inducing sleep also reverses memory defects in a Drosophila model of Alzheimer’s disease. Together these data demonstrate that sleep plays a more fundamental role in modulating behavioral plasticity than previously appreciated and suggests that increasing sleep may benefit patients with certain neurological disorders. PMID:25913403

  15. The influence of abdominal pigmentation on desiccation and ultraviolet resistance in two species of Drosophila.

    PubMed

    Matute, Daniel R; Harris, Alexandra

    2013-08-01

    Drosophila yakuba and D. santomea are sister species that differ in their levels of abdominal pigmentation; D. yakuba shows heavily pigmented posterior abdominal segments in both sexes, whereas D. santomea lacks dark pigment anywhere on its body. Using naturally collected lines, we demonstrate the existence of altitudinal variation in abdominal pigmentation in D. yakuba but not in D. santomea. We use the variation in pigmentation within D. yakuba and two body-color mutants in D. yakuba to elucidate selective advantage of differences in pigmentation. Our results indicate that although differences in abdominal pigmentation have no effect on desiccation resistance, lighter pigmentation confers ultraviolet radiation resistance in this pair of species.

  16. New setting for the Land O'Lakes Bioanalytical Conference.

    PubMed

    DeMuth, James E; Ho, Stacy; Briscoe, Chad; Cyronak, Matthew; Fluhler, Eric N; Ji, Qin C; Sriraman, Priya

    2013-11-01

    The University of Wisconsin bioanalytical conference is presented each year by the Extension Services in Pharmacy, the professional development department within the School of Pharmacy. The purpose of this 3-day conference was to provide an educational forum to discuss issues and applications associated with the analysis of xenobiotics, metabolites, biologics and biomarkers in biological matrices. The conference was designed to include and encourage an open exchange of scientific and methodological applications for bioanalysis. To increase the interactive nature of the conference the program was composed of a mixture of lectures, interactive discussions, poster sessions and roundtables. This paper summarizes the presentations at the Fourteenth Annual Conference, offered in a new venue.

  17. Conference report: emerging technology for bioanalysis in the next decade.

    PubMed

    Demuth, James E; Ji, Qin C; Booth, Brian P; Fluhler, Eric N; Greathead, Roger; Ho, Stacy; Stubbs, R John; Turk, Douglas J

    2012-11-01

    This University of Wisconsin School of Pharmacy bioanalytical conference is presented each year by the Extension Services in Pharmacy, the professional development department within the School. The purpose of this 4-day conference is to provide an educational forum to discuss issues and applications associated with the analysis of xenobiotics, metabolites, biologics and biomarkers in biological matrices. The conference is designed to include and encourage an open exchange of scientific and methodological applications for bioanalysis. To increase the interactive nature of the conference, the program was a mixture of lectures, poster sessions, round table discussions and workshops. This article summarizes the presentations at the 13th Annual Conference.

  18. Summary of the 2014 Land O'Lakes Bioanalytical Conference.

    PubMed

    DeMuth, James E; Fluhler, Eric N; Ho, Stacy; Cyronak, Matthew; Turk, Douglas J; Stubbs, R John; Moran, Jeffrey

    2014-01-01