Tripartite Motif-Containing Protein 5 (TRIM5) Human Recombinant Protein

The protein encoded by this gene is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The protein forms homo-oligomers via the coilel-coil region and localizes to cytoplasmic bodies. It appears to function as a E3 ubiquitin-ligase and ubiqutinates itself to regulate its subcellular localization. It may play a role in retroviral restriction. Multiple alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Dec 2009]

TRIM5: Isoform Alpha is a retrovirus restriction factor, which mediates species-specific, early block to retrovirus infection. Targets retroviral capsid soon after entry into the cell, and prevents reverse transcription of the virus RNA genome. Isoform Alpha trimers may make multiple contacts with the hexameric lattice of CA proteins which constitute the surface of retrovirion core, and somehow inactivate the virus. Restricts efficiently infection by N-MLV, but not HIV-1. May have E3 ubiquitin-protein ligase activity. Belongs to the TRIM/RBCC family. 6 isoforms of the human protein are produced by alternative splicing.

Protein type: EC 6.3.2.19; EC 6.3.2.-; Ubiquitin conjugating system; Ligase; Ubiquitin ligase

Chromosomal Location of Human Ortholog: 11p15

Cellular Component: cytoplasm; cytosol

Molecular Function: identical protein binding; protein binding; protein homodimerization activity; zinc ion binding; ubiquitin-protein ligase activity; pattern recognition receptor activity; ligase activity

Biological Process: positive regulation of I-kappaB kinase/NF-kappaB cascade; viral reproduction; positive regulation of MAPKKK cascade; negative regulation of virion penetration into host cell; cytokine and chemokine mediated signaling pathway; innate immune response; positive regulation of transcription factor activity; pattern recognition receptor signaling pathway; activation of innate immune response; regulation of lipopolysaccharide-mediated signaling pathway; defense response to virus; activation of NF-kappaB transcription factor