Tetraspanins as regulators of protein trafficking

Abstract

The four transmembrane proteins of the tetraspanin superfamily are the main structural units of specialised membrane microdomains referred to as tetraspanin-enriched microdomains, (TERM or TEM). Variations in homotypic and heterotypic interactions within TERM result in the modulation of signalling pathways involving tetraspanin associated receptors including integrins and receptor tyrosine kinases. It has recently become apparent that, in addition to their purely structural function as organisers of TERM, tetraspanins also regulate various aspects of trafficking and biosynthetic processing of associated receptors. In this chapter we will specifically focus on this aspect of tetraspanin function.