The protein encoded by this gene is a member of the TNF-receptor superfamily. This receptor is expressed by activated，but not by resting，T and B cells. TRAF2 and TRAF5 can interact with this receptor，and mediate the signal transduction that leads to the activation of NF-kappaB. This receptor is a positive regulator of apoptosis，and also has been shown to limit the proliferative potential of autoreactive CD8 effector T cells and protect the body against autoimmunity. Two alternatively spliced transcript variants of this gene encoding distinct isoforms have been reported. [provided by RefSeq，Jul 2008]