Cingulin (CGN)

Cingulin is a homodimer, each subunit containing a globular "head" domain, a long coiled-coil "rod" domain, and a small globular "tail". This domain organization is conserved throughout vertebrate species.However, cingulin homologs have not been detected in invertebrate species.

Cingulin is specifically localized at tight junctions in epithelial cells, unlike ZO-1, which is also detected at adherens-type junctions in non-epithelial cells. During early Xenopus embryo development, cingulin is detected at a cortical localization, and then accumulates at apical junctions, unlike ZO-1 and other junctional proteins, that are targeted to the new regions of cell-cell contact via the lateral domain.