Calpain 5 (CAPN5)

CAPN5 is one of the large subunits. Unlike some of the calpains, CAPN5 and CAPN6 lack a calmodulin-like domain IV. Because of the significant similarity to Caenorhabditis elegans sex determination gene tra-3, CAPN5 is also called as HTRA3.

Expression was observed in embryonic and newborn thymi, in various epithelial tissues, and in tissues of the central nervous system. In the thymus, Capn5 was expressed mainly in immature Cd25-positive embryonic thymocytes. Despite the widespread expression, most homozygous Capn5-null mice were viable and fertile and appeared healthy. Histopathologic analysis revealed no differences between Capn5-null and wildtype mice.