CD3D Part of the TCR-CD3 complex present on T-lymphocyte cell surface that plays an essential role in adaptive immune response. When antigen presenting cells (APCs) activate T-cell receptor (TCR), TCR-mediated signals are transmitted across the cell membrane by the CD3 chains CD3D, CD3E, CD3G and CD3Z. All CD3 chains contain immunoreceptor tyrosine-based activation motifs (ITAMs) in their cytoplasmic domain. Upon TCR engagement, these motifs become phosphorylated by Src family protein tyrosine kinases LCK and FYN, resulting in the activation of downstream signaling pathways. In addition of this role of signal transduction in T-cell activation, CD3D plays an essential role in thymocyte differentiation. Indeed, participates in correct intracellular TCR-CD3 complex assembly and surface expression. In absence of a functional TCR-CD3 complex, thymocytes are unable to differentiate properly. Interacts with CD4 and CD8 and thus serves to establish a functional link between the TCR and coreceptors CD4 and CD8, which is needed for activation and positive selection of CD4 or CD8 T-cells(PubMed:12215456). CD3D is mostly present on T-lymphocytes with its TCR-CD3 partners. Present also in fetal NK-cells. 2 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: Membrane protein, integral; Receptor, misc.
Chromosomal Location of Human Ortholog: 11q23.3
Cellular Component:  clathrin-coated vesicle membrane; cytoplasm; integral component of membrane; plasma membrane; T cell receptor complex
Molecular Function:  protein heterodimerization activity; protein homodimerization activity; transcription coactivator activity; transmembrane signaling receptor activity
Biological Process:  adaptive immune response; cell surface receptor signaling pathway; membrane organization; positive regulation of transcription by RNA polymerase II; positive thymic T cell selection; protein homooligomerization; regulation of immune response; T cell differentiation; T cell receptor signaling pathway
Disease: Immunodeficiency 19
Reference #:  P04234 (UniProtKB)
Alt. Names/Synonyms: CD3 antigen, delta subunit; CD3-DELTA; CD3D; CD3d antigen, delta polypeptide (TiT3 complex); CD3d molecule, delta (CD3-TCR complex); OKT3, delta chain; T-cell receptor T3 delta chain; T-cell surface glycoprotein CD3 delta chain; T3D
Gene Symbols: CD3D
Molecular weight: 18,930 Da
Basal Isoelectric point: 5.3  Predict pI for various phosphorylation states
CST Pathways:  T Cell Receptor Signaling
Select Structure to View Below


Protein Structure Not Found.

Cross-references to other databases:  STRING  |  cBioPortal  |  Wikipedia  |  Reactome  |  neXtProt  |  Protein Atlas  |  BioGPS  |  Pfam  |  RCSB PDB  |  Phospho3D  |  Phospho.ELM  |  NetworKIN  |  GeneCards  |  UniProtKB  |  Entrez-Gene  |  GenPept  |  Ensembl Gene  |  Ensembl Protein