DAP12 and KAP10 (DAP10)-novel transmembrane adapter proteins of the CD3zeta family.

Transmembrane adapter proteins are molecules that associate with receptors and mediate intracellular signals following interaction of the receptor with its ligand. Many such molecules have been characterized in detail, particularly the small TM adapters of the CD3zeta class at the core of the T cell receptor. Recently, two new genetically linked members of this class of transmembrane adapters have been identified called DAP12 (KARAP) and KAP10 (DAP10), respectively. In this review, we discuss this new class of TM adapters using the wealth of knowledge concerning CD3zeta and FcRgamma to highlight similarities and differences with DAP12 and KAP10. In addition, novel receptor families which interact with these TM adapters have also been identified. The role of these receptors and their inhibitory isoforms are discussed.