This domain, consisting of the distinct N-terminal PRY subdomain followed by the SPRY subdomain, is found at the C terminus of Trim58, also known as BIA2. TRIM proteins are defined by the presence of the tripartite motif RING/B-box/coiled-coil region, and are also known as RBCC proteins []. Trim58 has been implicated by genome-wide association studies (GWAS) in the regulation of erythrocyte traits, including cell size and number. Trim58 facilitates erythroblast enucleation by inducing proteolytic degradation of the microtubule motor dynein [].
TRIM58, also known as protein BIA2, is an erythroid E3 ubiquitin-protein ligase induced during late erythropoiesis. It binds and ubiquitinates the intermediate chain of the microtubule motor dynein (DYNC1LI1/DYNC1LI2), stimulating the degradation of the dynein holoprotein complex. It may participate in the erythroblast enucleation process through regulation of nuclear polarization. TRIM58 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain [].
