Tight Junction Associated Protein 1, Peripheral (TJAP1)

TJAP1 is a tight junction-associated protein. Incorporation of the encoded protein into tight junctions occurs at a late stage of formation of the junctions. The encoded protein localizes to the Golgi and may function in vesicle trafficking. Alternatively spliced transcript variants have been described. A related pseudogene exists on the X chromosome. TJAP1 contains an N-terminal coiled-coil domain and a central proline-rich region, and shares 74% amino acid identity with its mouse homolog. TJAP1 shares 43% and 51% amino acid identity over its N-terminal and C-terminal regions, respectively, with the same regions of BEGAIN. SDS-PAGE detected TJAP1 as an 86-kD band. Northern blot analysis detected an approximately 3.0-kb transcript in all 16 human tissues examined.