The name of this superfamily has been modified since the most recent official CATH+ release (v4_3_0). At the point of the last release, this superfamily was named:"
HIVs contain several virion-associated (auxiliary) proteins, such as Vpr and Vpx.
Vpx plays a role in nuclear translocation of the viral pre-integration complex (PIC) and is thus required for the virus to infect non-dividing cells. Vpr also plays a role in nuclear translocation of the PIC and may target specific host proteins for degradation by the 26S proteasome. It acts by associating with the cellular CUL4A-DDB1 E3 ligase complex through direct interaction with host VPRPB/DCAF-1. This would result in cell cycle arrest or apoptosis in infected cells, creating a favourable environment for maximising viral expression and production by rendering the HIV-1 LTR transcription more active.
The C-terminal domain (52-96) of Vpr seems to be involved in the most important functions of the protein, such as DNA interaction and apoptosis via interaction with the adenine nucleotide translocator. Vpr contains a Leu/Ile-rich domain (amino acids 60-81) in its C-terminal part, which is critical for dimerisation PMID:15571493. The C-terminal domain (amino acids 52-96) of Vpr was shown to be involved in cell cycle arrest, to bind the nucleocapsid protein NCp7, and to interact with HIV-1 RNA. Furthermore, this domain is thought to promote nuclear provirus transfer.
|Domain clusters (>95% seq id):||1|
|Domain clusters (>35% seq id):||1|
|Structural Clusters (5A):||1|
|Structural Clusters (9A):||1|