May be involved in mediating calcium-activated chloride conductance. The C-terminus 30 kDa form is anchored to the membrane. The N-terminus 110 kDa form is released from the membrane triggered by an unknown stimulus. Associated with the microvilli of non-goblet cell enterocytes in the small and large intestine. Colocalizes with CFTR. Expressed in the non-goblet intestinal cells. High levels in intestine and stomach, and lower levels in eye, liver and spleen. Increasing expression from the duodenum to the ilium, and decreasing expression to the colon. Isoform 2 is expressed in intestine and stomach but at lower levels than isoform 1. The metalloprotease region is responsible for autoproteolytic processing. It can also cross-cleave other CLCA substrates. N-Glycosylated. The translation product is autoproteolytically cleaved by the metalloprotease domain in the endoplasmic reticulum into a N-terminal and a C-terminal products that remain physically associated with each other. The cleavage is necessary for calcium-activated chloride channel (CaCC) activation activity. Belongs to the CLCR family.