Article

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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