Tetraspanin 1 (TSPAN1)

TSPAN1 belongs to the large family of tetraspanins, so named because they contain 4 transmembrane domains. Tetraspanins are frequently expressed at the cell surface in association with each other and with other molecules, such as integrins, and they function to regulate cell adhesion, migration, proliferation, and differentiation.

The deduced 242-amino acid protein contains 4 transmembrane domains and other features characteristic of tetraspanins, including conservation of charged residues in or near the transmembrane domains, similar to ion channels, and of 4 cysteines in the second extracellular domain. EST database analysis suggested that TSPAN2 is expressed in colon, endometrium, pancreas, normal and neoplastic prostate, and pregnant uterus.