TM4SF3 is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. Most of these members are cell surface proteins that are characterized by the presence of four hydrophobic domains. The proteins mediate signal transduction events that play a role in the regulation of cell development, activation, growth and motility. TM4SF3 is known to complex with integrins. Its gene is expressed in different carcinomas. The use of alternate polyadenylation sites has been found for TM4SF3 gene.