archive-edu.com » EDU » D » DUKE.EDU

Total: 837

Choose link from "Titles, links and description words view":

Or switch to "Titles and links view".
  • Duke University Department of Molecular Genetics & Microbiology
    ability to survive in mice and find that many of these mutants are not only avirulent but also are eliminated in vivo which is the acid test for a good antifungal drug target Chronological Life Span Starvation is used to study an important aspect of aging c hronological l ife s pan CLS In principle starvation for any one of the 20 amino acids which presumably results in the accumulation of the cognate uncharged tRNA s Gcn2p activation and inhibition of translation initiation might be expected to elicit the same stress response and to have the same effect on CLS However in carefully designed experiments in S cerevisiae that avoid toxic amino acid biosynthetic intermediates and satisfy any secondary auxotrophic requirements we find that amino acid starvation CLS is more complex and far more interesting Rather than starvation for each amino acid having the same effect on CLS we find that amino acid starvation CLS is amino acid specific varying across a 1 000 range Thus there are amino acid specific starvation CLS responses that are likely relevant to other stresses and as with general control are likely evolutionarily conserved Quantitative genetics in S cerevisiae S cerevisiae is a model eukaryote an excellent model for quantitative genetics and an emerging opportunistic pathogen In addition to some population genetics the pathogenesis aspect of this area of this research is two fold analysis of the quantitative traits of growth survival in serum originally growth survival in mice and high temperature growth in vitro The non pathogenesis aspect of this area of research looks at a variety of seemingly unrelated quantitative traits such as high temperature growth mitochondrial genome maintenance sporulation cycloheximide resistance etc One key to our analysis of quantitative traits is that we are oligonucleotide tagging all of the segregants which

    Original URL path: http://mgm.duke.edu/faculty/mccusker/index.htm (2014-06-13)
    Open archived version from archive

  • Duke University Department of Molecular Genetics & Microbiology
    including those utilizing yeasts as experimental microbial systems and those probing the interactions of infectious agents with cellular or heterologous host model systems Much of the history of modern molecular biology can be traced directly to genetic approaches with microbial and infectious systems including the discoveries of DNA and RNA as the genetic material the elucidation of the genetic code and the development of recombinant DNA approaches based on bacterial restriction modification systems and related enzymes Existing areas of strength in the Department include 1 microbiology virology mycology bacteriology 2 RNA biology and genomic expression analysis 3 yeast genetics 4 genetics of model systems and humans 5 chromosome structure function replication and repair and 6 epigenetics Eligibility and Criteria MGM SURE is open to Duke undergraduate students who have completed or are currently enrolled in at least one biological sciences course With the exception of graduating seniors all Duke undergraduates are eligible to apply Prior research experience is not required since the goal of the program is to immerse students in cutting edge research labs where they can acquire skills in experimental practices data analysis and interpretation and effective science communication Those undergraduates currently involved in research in MGM labs are also eligible to apply We encourage women and individuals from underrepresented groups to apply Students will be selected based on academic record letters of recommendation and descriptions of research interests and goals The research engagement will run from June 2 2014 August 8 2014 Students must be present full time for the entire summer program and may not be enrolled in courses during the research engagement period Number of Awards In summer 2014 MGM SURE will grant four to six awards to support summer research projects of 10 weeks in duration Each award includes a 4000 stipend to help

    Original URL path: http://mgm.duke.edu/news/mgm_sure.html (2014-06-13)
    Open archived version from archive

  • Duke University Department of Molecular Genetics & Microbiology
    that knocking down HuR increases mRNA instability while antagonizing microRNA mediated repression This suggests that HuR competes with microRNAs to override their typically inhibitory functions Although important in proliferating mammalian cells little is known about the RBP miRNA dynamics that take place during tumorigenesis Bisogno set up a step wise cell culture model of breast cancer in which to study HuR in addition to other RBPs and microRNA target dynamics that occur during the transition from a normal primary epithelial cell to a fully transformed malignant cell This approach will provide a comprehensive understanding of coordinated post transcriptional regulation necessary for the acquisition of the cancer related gene expression program Anthony Moore a graduate student in the University Program in Genetics and Genomics UPGG working in the laboratory of Tom Petes PhD in the Department of Molecular Genetics and Microbiology was recently awarded an Underrepresented Individuals in Science Supplement from the National Institutes of Health NIH for a proposal entitled Genetic regulation of genome stability in yeast The Petes lab is active in three research areas 1 the cellular mechanisms that regulate genome stability 2 the genetic control of the replication and maintenance of chromosome ends telomeres and 3 the mechanisms that control the level of meiotic recombination Almost all studies are done using the yeast Saccharomyces cerevisiae Moore s research background varies from an ecological study of an invasive apple snail species to population genetics survey of a Ugandan rat His scientific interests focus on locating those ecologically and or evolutionary important variations in phenotypes or behaviors and locating the variations at the regulatory genetic and developmental level that lead to those variations His passion remains in ecology and evolutionary biology with a fundamental molecular focus Emily Snavely a graduate student in Molecular Genetics and Microbiology working in the

    Original URL path: http://mgm.duke.edu/news/four_fellowships.html (2014-06-13)
    Open archived version from archive

  • Duke University Department of Molecular Genetics & Microbiology
    to increase the number of underrepresented minority scientists participating in biomedical research and the health related sciences Although the NIH currently provides opportunities for miniorities through traditional research grant programs and special initiatives supported by various components of the NIH this need has remained The NIH has continued its efforts to establish a diversified workforce by increasing the number of individuals from underrepresented racial and ethnic groups actively participating in biomedical research In addtion in recent years it has become increasingly clear that there is a serious health care disparity among minority groups in this country The NIH recognizes the need to expand research opportunities for minority scientists to help eliminate health disparities Sloan was also recently selected to receive a 2014 Samuel DuBois Cook Society Sammie Award which will be presented at the annual dinner and awards ceremony on Tuesday February 18th at the Washington Duke Inn The Cook Society was founded in 1997 to recognize the contributions of the first African American professor hired and tenured at Duke University The Society was intended to be an instrument of social engagement and change and seeks to recognize members of the Duke community who reflect in their work or academic

    Original URL path: http://mgm.duke.edu/news/sloan.html (2014-06-13)
    Open archived version from archive

  • Duke University Department of Molecular Genetics & Microbiology
    ancestry had children with similar impairments small head circumference that grows progressively worse accompanied by profound developmental delays and seizures Deducting that the families ethnic heritage might help focus the gene quest Goldstein and colleagues looked for gene variants that were shared by the two affected children from one of the families but were uncommon in the general population Of 72 such variants three were absent in the larger population Of those three variants one was also present in the child of the other family from Israel This mutation was located in the asparagine synthetase gene or ASNS which controls the production of the metabolite asparagine from other amino acids Meanwhile two other families both in Canada had children who were born with similar problems and scientists there conducted analyses that pointed to mutations in the same ASNS genes In combining the cases the researchers discovered that each of the parents in these four families shared a rare recessive trait that by chance combined to result in a newly identified disorder in their children More cases are likely to come to light now that the gene mutation has been identified Goldstein said other similar deficiencies in amino acids synthesization all causing neurological problems have recently been identified These conditions have shown improvement with the use of dietary supplements suggesting that the impairments caused by the ASNS mutation might benefit from asparagine supplementation An emerging theme is that with these non essential amino acids their metabolism does matter Goldstein said This metabolic pathway is important and it may be that the amount of asparagine is the key or a buildup of toxin in that pathway caused by the mutation Goldstein said future research in mice bred to have a similar disorder could prove enlightening Already he said experiments have shown that

    Original URL path: http://mgm.duke.edu/news/goldstein_4.htm (2014-06-13)
    Open archived version from archive

  • Duke University Department of Molecular Genetics & Microbiology
    or lymphomas can be studied in B cells infected in the laboratory The Luftig lab focuses on understanding how viral proteins trigger B cells to proliferate in an uncontrolled manner In particular Alex will focus on one protein LMP1 that is essential for EBV mediated B cell immortalization and is thought to be the major viral oncoprotein in cancer In addition to his recent fellowship Alex has led a study that was published in the Journal of Virology and highlighted as a Spotlight Editor s Choice Article and also recently completed a review article for Advances in Virus Research entitled Dynamic Epstein Barr virus gene expression on the path to B cell transformation This work has changed the way we view EBV transformation of B cells says Micah Luftig Assistant Professor in Molecular Genetics and Microbiology and Deputy Director of the Duke University Center for Virology This was once thought to proceed as a binary switch of uninfected to infected cell However what is now clear is that EBV regulates B cell gene expression through at least two distinct phases after infection leading to the cell being transformed Alex s work suggests that we should consider the dynamics of this

    Original URL path: http://mgm.duke.edu/news/price.html (2014-06-13)
    Open archived version from archive

  • Duke University Department of Molecular Genetics & Microbiology
    It causes more than 600 000 deaths a year from cryptococcal pneumonia and meningoencephalitis accounting for a third of all AIDS related deaths Researchers have been interested in the sexual cycle of Cryptococcus because it is the only way this fungal pathogen can produce spores to infect its host Though it has two mating types namely a and alpha the vast majority of the fungi found in nature are of the alpha variety Many had assumed this finding meant the fungi had given up on finding mates and was resorting to asexual reproduction That is until a previous study by Heitman and his colleague and former fellow Xiaorong Lin showed that Cryptococcus engaged in a phenomenon known as unisexual reproduction or sex involving fungi of the same mating type That was a big mystery because if there are two identical genomes coming together the end product should be the same as if the fungi had just cloned itself through asexual reproduction said Heitman We were trying to get a sense of is it just spinning its wheels or maybe there is some other function to it Heitman hypothesized that sex might be a means of creating genetic diversity To test this hypothesis he and his colleagues former fellow Min Ni and current graduate student Marianna Feretzaki grew the microbe in two different ways one where it underwent asexual reproduction the other where it underwent unisexual reproduction They then took the offspring of those reproductive cycles and compared them to each other and to the starting parent The researchers found the offspring of asexual reproduction were essentially clones looking just like each other and just like the parent On the other hand some of the offspring of unisexual reproduction differed both in terms of genetic makeup and behavior Those differences were due to a distinct genetic change called aneuploidy or having more than the normal number of DNA packaging chromosomes Aneuploidy is well known to be deleterious in humans causing genetic disorders like Down s syndrome or trisomy 21 But having an extra chromosome can actually be beneficial in microbes like Cryptococcus where it has been shown to confer drug resistance to the antifungal fluconazole In this study the researchers discovered that aneuploidy could lead to beneficial neutral or detrimental changes in the fitness of the offspring For example offspring with an extra copy of chromosome 9 or 10 became drug resistant and were able to outcompete their parent when subjected to antifungal treatment Heitman and his colleagues also used some of the aneuploid offspring to infect animal models and showed they could be just as virulent as the parent suggesting how new properties drug resistance and old ones virulence could be combined An interesting feature of aneuploidy is it can be temporary said Heitman If at some point it stops being beneficial or adaptive the fungi can lose the chromosome just as easily as they gained it In fact we showed that if we took the aneuploid offspring and let

    Original URL path: http://mgm.duke.edu/news/heitman_11.html (2014-06-13)
    Open archived version from archive

  • Duke University Department of Molecular Genetics & Microbiology
    of both the human and mosquito hosts and to elucidate the role of these proteins in regulating virus replication This work will advance the field of dengue virus biology by not only informing our understanding of the molecular mechanisms of virus replication but also by revealing potential candidate targets for anti viral compounds I am pleased that the NIH is as enthusiastic about this research as I am and I

    Original URL path: http://mgm.duke.edu/news/phillips.html (2014-06-13)
    Open archived version from archive