BST-2 Downregulation and Enhancement of HIV-1 Release by vpu

Andrey Tokarev, Veteran Medical Research Foundation, San Diego
Mentor: John Guatelli
Basic Biomedical Sciences
Postdoctoral Fellowship Award

The innate immune response protein BST-2 captures HIV-1 virions at the cell surface and drives them into an unidentified intracellular compartment, limiting the spread of infection. The HIV-1 accessory protein Vpu removes BST-2 from the cell surface and enhances virion release by an unknown mechanism. Recent data raised the possibility that Vpu affects ubiquitin-dependent internalization/trafficking of BST-2. This downregulation should take place before virion release from the cell surface, in order to avoid Vpu interference with the release of virions bound to BST-2. Alternatively, Vpu could preferentially downregulate BST-2, not associated with virions, or both BST-2 and BST-2/virion complexes. This study aims to understand the mechanism of BST-2 downregulation from the cell surface by Vpu, as well as the relationship between this downregulation and virion release. Elucidating the mechanisms of the interaction between HIV-1 and the host cells will reveal new potential targets for anti-HIV-1 therapy and vaccination.