Tripartite motif-containing protein 5 (TRIM5) is a RING domain-E3 ubiquitin ligase that restricts infection by human immunodeficiency virus (HIV)-1 and other retroviruses immediately following virus invasion of the target cell cytoplasm []. It is a regulator of autophagy [].Interestingly, while each primate species has a single TRIM5 gene, mice have at least seven TRIM5 homologues that cluster into two groups, Trim12a, -b, and -c and Trim30a, -b, -c, and -d. The three Trim12 proteins activated innate immune signaling, while the Trim30 proteins did not [].
This zinc-finger is typical of ubiquitin ligases from eukaryotes [, ]. This domain can also be found in Tripartite motif-containing proteins (TRIM), including TRIM5 from humans, a capsid-specific restriction factor that prevents infection from non-host-adapted retroviruses [, ].
