| Modification Notes |
Infection by human immunodeficiency virus (HIV) is associated with an early immune dysfunction and progressive destruction of CD4+T lymphocytes. The HIV-induced, premature destruction of lymphocytes is associated with the continuous production of HIV viral proteins, which modulate apoptotic pathways. The virion-associated protein (Vpr), an accessory protein of HIV, affects viral replication, as well as cell growth, differentiation and apoptosis. Involved in the pathogenesis of T cell depletion in HIV-infected people, Vpr has been shown to enhance the nuclear transport of the HIV-1 pre-integration complex, activate transcription of cellular and viral promoters and arrest the cell cycle at the G2/M checkpoint. VPRBP (Vpr (HIV-1) binding protein), also known as DCAF1 or RIP, is a 1,507 amino acid cytoplasmic protein that contains one LisH domain and functions as a Vrp binding protein. Expressed ubiquitously, VPRBP is thought to act as a receptor for the CUL-4-DDB1 complex and, in response to HIV infection, interacts with Vpr and may cause cell cycle arrest at the G2 phase. Multiple isoforms of VPRBP exist due to alternative splicing events. |