Skip to content
University of Maryland LibrariesDigital Repository at the University of Maryland
    • Login
    View Item 
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    GENOME-WIDE ANALYSIS OF CHICKEN MIRNAS AND DNA METHYLATION AND THEIR ROLES IN MAREK'S DISEASE RESISTANCE AND SUSCEPTIBILITY

    Thumbnail
    View/Open
    Tian_umd_0117E_13662.pdf (3.137Mb)
    No. of downloads: 1489

    Date
    2012
    Author
    Tian, Fei
    Advisor
    Song, Jiuzhou
    Metadata
    Show full item record
    Abstract
    Marek's disease (MD) is a T cell lymphoma in chickens and causes high mortality and morbidity in productive chickens. Two inbred chicken lines, resistant line 63 and susceptible line 72, with the same MHC haplotype, showed distinct disease outcomes after MDV infection. The current studies aimed to illustrate the role of microRNA (miRNAs) and DNA methylation in MD resistance and susceptibility in chickens. First, to ascertain the function of miRNAs, miRNA microarray experiments were used to identify miRNAs sensitive to MDV infection in the 2 lines. Most miRNAs were repressed in line 72 after MDV infection, while their transcription was steady in line 63. The miRNA target genes were identified in chickens. Cellular miRNA gga-miR-15b and gga-let-7iwere reduced in infected line 72 chickens and MD tumors. The downregulation of the two miRNAs increased the expression of ATF2 (activating transcription factor 2) and DNMT3a (DNA methyltransferase 3a) in infected line 72. These results indicated that miRNAs may play antiviral functions through modulating target gene expression. Next, to characterize the role of miRNAs in MDV infection, the selected chicken miRNAs were overexpressed in MDV infected DF-1 cells. The overexpressions of chicken miRNA gga-miR-15b and gga-let-7i, by using the retroviral based vector, significantly restricted MDV replications in vitro. MDV oncoprotein was repressed, suggesting that chicken miRNAs may limit MDV propagation. Finally, we found deregulation of transcription of DNA methyltransfereases (DNMTs) in lines 63 and 72 after MDV infection, which coordinated with the methylation alterations in the 2 lines. Infection induced differential methylation regions (iDMRs) that were identified through genome-wide DNA methylation quantification. Genes overlapping line-specific iDMRs were related with pathways of different functions in these two lines, implying the involvement of DNA methylation in MD- resistance and susceptibility. An in vitro study showed that DNA methylation inhibitor repressed viral spread and viral replication. In conclusion, the observed variations of miRNA expression and DNA methylation may be associated with disease predisposition in chickens.
    URI
    http://hdl.handle.net/1903/13670
    Collections
    • Animal & Avian Sciences Theses and Dissertations
    • UMD Theses and Dissertations

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility
     

     

    Browse

    All of DRUMCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister
    Pages
    About DRUMAbout Download Statistics

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility