[5][6] The protein encoded by this gene 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.

This encoded protein is a cell surface glycoprotein and is similar in sequence to its family member CD53 antigen.

Alternatively spliced transcript variants encoding different isoforms have been identified.