T-cell surface glycoprotein CD3 zeta/eta subunit/High affinity IgE receptor gamma subunit (IPR021663)

Short name: CR3_zeta/IgE_Fc_rcpt_gamma

Family relationships


The TCR complex of T-lymphocytes consists of either a TCR alpha/beta or TCR gamma/delta heterodimer co-expressed at the cell surface with the invariant subunits of CD3 labelled gamma, delta, epsilon, zeta, and eta [PMID: 9072162]. The zeta subunit forms either homodimers or heterodimers with eta [PMID: 8112294], but eta homodimers have not been observed. The structure of the zetazeta transmembrane dimer consists of a left-handed coiled coil with polar contacts. Two aspartic acids are critical for zetazeta dimerisation and assembly with TCR [PMID: 17055436].

The high affinity immunoglobulin epsilon receptor (IgE Fc receptor) subunit gamma associates with a variety of FcR alpha chains to form a functional signaling complex. The gamma subunit has a critical role in allowing the IgE Fc receptor to reach the cell surface and regulates several aspects of the immune response [PMID: 8611682].

This family includes both CD3 zeta subunits and IgE Fc receptor gamma subunits. The gamma chain of the high affinity Fc receptor for IgE has significant structural homology to CD3 zeta and the related CD3 eta subunit and can facilitate T cell receptor expression and signaling in the absence of CD3 zeta and CD3 eta [PMID: 1714902].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.