CD3D

CD3D also known as CD3-DELTA, is a part of the T-cell receptor/CD3 complex (TCR/CD3 complex). This protein is associated with T-cell development and signal transduction. And it represents the delta subunit of the CD3 complex, and together with four other CD3 subunits, binds either TCR alpha/beta or TCR gamma/delta to generate the TCR/CD3 complex on the surface of T-cells. CD3D is expressed in a variety of tissues, including brain, endocrine tissues, muscle tissues, lung, liver and gallbladder, kidney and urinary bladder, skin, as well as adipose and soft tissue.
The T cell-receptor complex is composed of the alpha and beta or gamma and delta variant chains, paired as mutationally exclusive heterodimers, in combination with the invariant chains CD3-delta (CD3D), CD3-zeta (CD3Z), CD3-gamma (CD3G), CD3-epsilon (CD3E). T cells with alpha (TCRA) and beta (TCRB) chains are considered to as alpha/beta T cells, and T cells with gamma (TCRG) and delta (TCRD) chains are known as gamma/delta T cells. To date, during development, the CD3 protein complex serves a crucial role in the transition of thymocytes from immature precursors to the final mature CD4+ or CD8+ single-positive T cell. Importantly, selective deficiency of any 1 of the 4 CD3 components in mice, performed by gene knockout, induces mild to severe, although incomplete, blockage of T cell development.
Gene ID: 915
UniProt ID: P04234