VPR | |||||||||
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Identifiers | |||||||||
Symbol | VPR | ||||||||
Pfam | PF00522 | ||||||||
InterPro | IPR000012 | ||||||||
SCOP2 | 1dsk / SCOPe / SUPFAM | ||||||||
TCDB | 1.A.42 | ||||||||
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Vpr is a Human immunodeficiency virus gene and protein product.[1][2] Vpr stands for "Viral Protein R". Vpr, a 96 amino acid 14-kDa protein, plays an important role in regulating nuclear import of the HIV-1 pre-integration complex, and is required for virus replication and enhanced gene expression from provirus in dividing or non-dividing cells such as T cells or macrophages.[3] Vpr also induces G2 cell cycle arrest and apoptosis in proliferating cells, which can result in immune dysfunction.[4][5]
Vpr is also immunosuppressive due to its ability to sequester a proinflammatory transcriptional activator in the cytoplasm. HIV-2 contains both a Vpr protein and a related (by sequence homology) Vpx protein (Viral Protein X). Two functions of Vpr in HIV-1 are split between Vpr and Vpx in HIV-2, with the HIV-2 Vpr protein inducing cell cycle arrest and the Vpx protein required for nuclear import.