PRY/SPRY domain in tripartite motif-binding protein 69 (TRIM69), also known as RING finger protein 36 (RNF36)
This domain, consisting of the distinct N-terminal PRY subdomain followed by the SPRY subdomain, is found at the C-terminus of TRIM69, which is also known as RING finger protein 36 (RNF36) or testis-specific ring finger (Trif). TRIM69 domains are composed of RING/B-box/coiled-coil core and also known as RBCC proteins. It is a novel testis E3 ubiquitin ligase that may function to ubiquitinate its particular substrates during spermatogenesis. In humans, TRIM69 localizes in the cytoplasm and nucleus, and requires an intact RING finger domain to function. The mouse ortholog of this gene is specifically expressed in germ cells at the round spermatid stages during spermatogenesis and, when overexpressed, induces apoptosis. TRIM69 has been shown to be a novel regulator of mitotic spindle assembly in tumor cells; it associates with spindle poles and promotes centrosomal clustering, and is therefore essential for formation of a bipolar spindle.