FunctionPlays a major role in tight junction-specific obliteration of the intercellular space, through calcium-independent cell-adhesion activity. Involved in paracellular magnesium reabsorption. Required for a selective paracellular conductance. May form, alone or in partnership with other constituents, an intercellular pore permitting paracellular passage of magnesium and calcium ions down their electrochemical gradients. Alternatively, it could be a sensor of magnesium concentration that could alter paracellular permeability mediated by other factors.
Tissue specificityKidney-specific, including the thick ascending limb of Henle (TAL).
Involvement in diseaseDefects in CLDN16 are the cause of hypomagnesemia type 3 (HOMG3) [MIM:248250]; also known as familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC). HOMG3 is a progressive renal disease characterized by primary renal magnesium wasting with hypomagnesemia, hypercalciuria and nephrocalcinosis. Recurrent urinary tract infections and kidney stones are often observed. In spite of hypercalciuria, patients do not show hypocalcemia.
Sequence similaritiesBelongs to the claudin family.