PRY/SPRY domain of tripartite motif-binding protein 60 and 75 (TRIM60 and TRIM75)
This domain, consisting of the distinct N-terminal PRY subdomain followed by the SPRY subdomain, is found at the C-terminus of TRIM60 and TRIM75, both composed of RING/B-box/coiled-coil core and also known as RBCC proteins. TRIM60 domain is also known as RING finger protein 33 (RNF33) or 129 (RNF129). Based on its expression profile, RNF33 likely plays an important role in the spermatogenesis process, the development of the pre-implantation embryo, and in testicular functions; Rnf33 is temporally transcribed in the unfertilized egg and the pre-implantation embryo, and is permanently silenced before the blastocyst stage. Mice experiments have shown that RNF33 associates with the cytoplasmic motor proteins, kinesin-2 family members 3A (KIF3A) and 3B (KIF3B), suggesting possible contribution to cargo movement along the microtubule in the expressed sites. TRIM75, also known as Gm794, has a single site of positive selection in its RING domain associated with E3 ubiquitin ligase activity. It has not been detectably expressed experimentally due to their constant turnover by the proteasome, and therefore not been characterized.