function:Plays a major role in tight junction-specific obliteration of the intercellular space, through calcium-independent cell-adhesion activity.,similarity:Belongs to the claudin family.,subunit:Can form homo- and heteropolymers with other CLDN. Homopolymers interact with CLDN3, but not CLDN1, homopolymers. Directly interacts with TJP1/ZO-1, TJP2/ZO-2 and TJP3/ZO-3.,