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

Short name: CD3_zeta/IgE_Fc_rcpt_gamma

Overlapping homologous superfamilies


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]. It 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].

This family includes both CD3 zeta subunits and IgE Fc receptor gamma subunits.

Contributing signatures

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