Chloride channel protein 2 (ClC-2) (CLCN2)

Chloride channel protein 2 (ClC-2), encoded by the CLCN2 gene, is a member of the voltage-gated chloride channel family (UniProt: P51788). It is expressed in various tissues, including the gastrointestinal tract, central nervous system, and kidneys, where it mediates the passive transport of chloride ions down their electrochemical gradient (PubMed: 15155609). In the intestinal epithelium, ClC-2 is localized to the apical membrane and plays a pivotal role in regulating fluid secretion and maintaining mucosal barrier integrity. Pharmacologically, ClC-2 is the primary molecular target of Lubiprostone, a prostone-derived activator used to treat chronic idiopathic constipation and opioid-induced constipation by increasing luminal fluid secretion (DrugBank: DB01046). Clinically, mutations in the CLCN2 gene are associated with diverse conditions, such as childhood absence epilepsy and leukoencephalopathy with ataxia, as well as gain-of-function variants linked to primary aldosteronism (PubMed: 26034110, PubMed: 29403010). Its involvement in both ion homeostasis and specialized fluid transport makes it a significant focus for pharmaceutical research in gastrointestinal and endocrine medicine.

Other names

CLC2ClC-2Voltage-gated chloride channel 2Type-2 chloride channel

Activation of the channel increases chloride ion conductance across the apical membrane of intestinal epithelial cells, promoting the secretion of water and electrolytes into the intestinal lumen to facilitate bowel movement.