The Human Immunodeficiency Virus Type 1 Vpr Transactivator: Cooperation with Promoter-bound Activator Domains and Binding to TFIIB

Vpr and Vpu Are Important for Efficient Human Immunodeficiency Virus Type 1 Replication and CD4 + T-Cell Depletion in Human Lymphoid Tissue Ex Vivo

“…Vpr is a virionassociated protein (10) which induces G 2 /M arrest (18,40) and plays a role in the nuclear transport of the preintegration complex in nondividing cells (39). Vpr also enhances infection of macrophages (14), activates HIV transcription (1,17), and induces apoptosis (38,44,47). Vpu promotes virion release (49,54) by counteracting host restriction factors (30,52), downregulates CD4 during the late stages of HIV-1 infection (34,53), and inhibits NF-B activation (3).…”

Cell-based chemical genetic screen identifies damnacanthal as an inhibitor of HIV-1 Vpr induced cell death

“…Vpr is a pleiotropic protein with multiple pathobiological mechanisms. These mechanisms include nuclear import of preintegration complex [14], transactivation of several viral promoters including long terminal repeat (LTR) [15,16], and induction of cell cycle arrest at G 2 /M phase (G 2 arrest) [17] and apoptosis [18,19]. Apoptosis induced by Vpr is believed to contribute to CD4+ T cell depletion [17,20].…”

Using death to one's advantage: HIV modulation of apoptosis

“…87,98 The exact mechanism by which Vpr increases protein synthesis is not clear, 99 however, it may be achieved by direct binding of Vpr to the transcription factors TFIIB and Sp1. 99,100 In proliferating T cells and stimulated peripheral blood mononuclear cells (PBMCs), Vpr appears to be dispensable for the in vitro replication of HIV. [101][102][103][104][105][106][107] However, under certain conditions, Vpr contributes substantially to HIV-1 replication in these cells.…”