• Login as Editor
    View Item 
    •   Yeshiva Academic Institutional Repository
    • Albert Einstein College of Medicine (AECOM)
    • Albert Einstein College of Medicine: Doctoral Dissertations
    • View Item
    •   Yeshiva Academic Institutional Repository
    • Albert Einstein College of Medicine (AECOM)
    • Albert Einstein College of Medicine: Doctoral Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Alphavirus entry and exit: Mechanisms of Semliki Forest virus budding

    Thumbnail

    Date
    2000
    Author
    Lu, Yanping Emily
    Metadata
    Show full item record
    Share
    Abstract
    Semliki Forest virus (SFV) and Sindbis virus (SIN), are two enveloped alphaviruses that are used extensively to study the mechanisms of membrane fusion and virus assembly. SFV and SIN enter the cells via endocytic pathway and low pH-mediated membrane fusion, and bud from the plasma membrane in a reaction requiring both the viral spike glycoproteins and the nucleocapsid.;The major part of my thesis focused on the establishment of a quantitative biochemical assay to study SFV budding, and its use to characterize the molecular requirements and mechanisms of SFV budding. This assay was based on cell-surface biotinylation of newly synthesized virus spike proteins and retrieval of biotinylated virions using strepavidin-conjugated magnetic particles. Budding of biotin-tagged SFV was continuous for at least two hours, independent of microfilaments and microtubules, strongly temperature dependent, and relatively independent of continuing exocytic transport. Studies of cell surface spike proteins at early times of infection showed that these spikes did not efficiently bud into virus particles and were rapidly degraded. In contrast, at later times of infection, spike protein degradation was markedly reduced and efficient budding was then observed, suggesting that efficient virus budding was dependent on a critical spike protein pool during the infection. The previously described cholesterol requirement in SFV exit was shown to be due to a block in the budding from the cell surface, and correlated with the continued degradation of spike proteins at all times of virus infection in sterol-deficient cells. In addition, the cholesterol requirement for virus budding could be modulated by a single point mutation in the spike protein. A model has been proposed on the mechanisms of SFV budding and cholesterol requirement.;Another aspect of my thesis focused on the cholesterol requirement for SIN infection and exit. I have shown that SIN, a distantly related alphavirus to SFV, is also strongly dependent on cellular cholesterol for the growth, primary infection, fusion, and exit, suggesting a general role of cholesterol in alphavirus entry and exit. Mutagenesis studies demonstrated that, similar to SFV, SIN cholesterol requirement can be modulated by sequences within the viral spike proteins.
    Permanent Link(s)
    https://ezproxy.yu.edu/login?url=http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqm&rft_dat=xri:pqdiss:9985207
    https://hdl.handle.net/20.500.12202/3908
    Citation
    Source: Dissertation Abstracts International, Volume: 61-09, Section: B, page: 4516.;Advisors: Margaret C. Kielian.
    *This is constructed from limited available data and may be imprecise.
    Collections
    • Albert Einstein College of Medicine: Doctoral Dissertations [1674]

    Yeshiva University Libraries copyright © 2021  DuraSpace
    YAIR Self-Deposit | YAIR User's Guide | Take Down Policy | Contact Us
    Yeshiva University
     

     

    Browse

    AllCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    Login as Editor

    Statistics

    View Usage Statistics

    Yeshiva University Libraries copyright © 2021  DuraSpace
    YAIR Self-Deposit | YAIR User's Guide | Take Down Policy | Contact Us
    Yeshiva University