The Role of Cellular Factors in Promoting HIV Budding

Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605, USA.
Journal of Molecular Biology (Impact Factor: 3.96). 07/2011; 410(4):525-33. DOI: 10.1016/j.jmb.2011.04.055
Source: PubMed

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) becomes enveloped while budding through the plasma membrane, and the release of nascent virions requires a membrane fission event that separates the viral envelope from the cell surface. To facilitate this crucial step in its life cycle, HIV-1 exploits a complex cellular membrane remodeling and fission machinery known as the endosomal sorting complex required for transport (ESCRT) pathway. HIV-1 Gag directly interacts with early-acting components of this pathway, which ultimately triggers the assembly of the ESCRT-III membrane fission complex at viral budding sites. Surprisingly, HIV-1 requires only a subset of ESCRT-III components, indicating that the membrane fission reaction that occurs during HIV-1 budding differs in crucial aspects from topologically related cellular abscission events.

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