T-cell surface glycoprotein CD3 gamma chain (CD3G)

The T-cell surface glycoprotein CD3 gamma chain is a 182-amino acid transmembrane glycoprotein (~20-25 kDa) that pairs with other CD3 subunits (delta, epsilon, zeta) to form the CD3 complex, which is tightly associated with the TCR on T-cell surfaces. It provides critical scaffolding for assembly and signal propagation by presenting immunoreceptor tyrosine-based activation motifs (ITAMs) in its cytoplasmic tail that are phosphorylated on antigen engagement, triggering intracellular signaling cascades necessary for T-cell activation and immune response. CD3 gamma also regulates TCR surface expression and turnover. Defects in CD3 gamma are associated with human T-cell immunodeficiency syndromes due to impaired TCR signaling or surface expression. The CD3 gamma chain, as a core component of the TCR-CD3 complex, is the mainstay of diagnostic and therapeutic targeting in both research and clinical settings, and is indispensable for adaptive immune function.

Other names

T-cell receptor T3 gamma chainT3GCD3 gamma chainCluster of differentiation 3 gamma chain

Antibody binding causes modulation or depletion of T-cells through triggering of TCR complex signaling and subsequent apoptosis or anergy. Immunosuppression via blockade of T-cell activation. Downregulation of surface TCR/CD3 complex (internalization and degradation).