CAPN1
Calpain-1 catalytic subunit is a protein that in humans is encoded by the "CAPN1" gene. Function. The calpains, calcium-activated neutral proteases, are nonlysosomal, intracellular cysteine proteases. The mammalian calpains include ubiquitous, stomach-specific, and muscle-specific proteins. The ubiquitous enzymes consist of heterodimers with distinct large, catalytic subunits associated with a common small, regulatory subunit. This gene encodes the large subunit of the ubiquitous enzyme, calpain 1. Interactions. CAPN1 has been shown to interact with PSEN2.