2oq1
Tandem SH2 domains of ZAP-70 with 19-mer zeta1 peptide
Structural highlights
DiseaseZAP70_HUMAN Defects in ZAP70 are the cause of selective T-cell defect (STCD) [MIM:269840. A form of severe combined immunodeficiency characterized by a selective absence of CD8+ T cells.[1] [2] [3] [4] [5] FunctionZAP70_HUMAN Tyrosine kinase that plays an essential role in regulation of the adaptive immune response. Regulates motility, adhesion and cytokine expression of mature T-cells, as well as thymocyte development. Contributes also to the development and activation of primary B-lymphocytes. When antigen presenting cells (APC) activate T-cell receptor (TCR), a serie of phosphorylations lead to the recruitment of ZAP70 to the doubly phosphorylated TCR component CD247/CD3Z through ITAM motif at the plasma membrane. This recruitment serves to localization to the stimulated TCR and to relieve its autoinhibited conformation. Release of ZAP70 active conformation is further stabilized by phosphorylation mediated by LCK. Subsequently, ZAP70 phosphorylates at least 2 essential adapter proteins: LAT and LCP2. In turn, a large number of signaling molecules are recruited and ultimately lead to lymphokine production, T-cell proliferation and differentiation. Furthermore, ZAP70 controls cytoskeleton modifications, adhesion and mobility of T-lymphocytes, thus ensuring correct delivery of effectors to the APC. ZAP70 is also required for TCR-CD247/CD3Z internalization and degradation through interaction with the E3 ubiquitin-protein ligase CBL and adapter proteins SLA and SLA2. Thus, ZAP70 regulates both T-cell activation switch on and switch off by modulating TCR expression at the T-cell surface. During thymocyte development, ZAP70 promotes survival and cell-cycle progression of developing thymocytes before positive selection (when cells are still CD4/CD8 double negative). Additionally, ZAP70-dependent signaling pathway may also contribute to primary B-cells formation and activation through B-cell receptor (BCR).[6] [7] [8] [9] [10] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe crystal structure of the tandem SH2 domains of human ZAP-70 in complex with a peptide derived from the zeta-subunit of the T-cell receptor reveals an unanticipated interaction between the two domains. A coiled coil of alpha-helices connects the two SH2 domains, producing an interface that constitutes one of the two critical phosphotyrosine binding sites. These and other unique features provide the molecular basis for highly selective association of ZAP-70 with the T-cell receptor. Molecular basis for interaction of the protein tyrosine kinase ZAP-70 with the T-cell receptor.,Hatada MH, Lu X, Laird ER, Green J, Morgenstern JP, Lou M, Marr CS, Phillips TB, Ram MK, Theriault K, et al. Nature. 1995 Sep 7;377(6544):32-8. PMID:7659156[11] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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