3d7u

Structural highlights

Function

[CSK_HUMAN] Non-receptor tyrosine-protein kinase that plays an important role in the regulation of cell growth, differentiation, migration and immune response. Phosphorylates tyrosine residues located in the C-terminal tails of Src-family kinases (SFKs) including LCK, SRC, HCK, FYN, LYN or YES1. Upon tail phosphorylation, Src-family members engage in intramolecular interactions between the phosphotyrosine tail and the SH2 domain that result in an inactive conformation. To inhibit SFKs, CSK is recruited to the plasma membrane via binding to transmembrane proteins or adapter proteins located near the plasma membrane. Suppresses signaling by various surface receptors, including T-cell receptor (TCR) and B-cell receptor (BCR) by phosphorylating and maintaining inactive several positive effectors such as FYN or LCK.^{[1] [2]} [SRC_CHICK] Non-receptor protein tyrosine kinase which is activated following engagement of many different classes of cellular receptors including immune response receptors, integrins and other adhesion receptors, receptor protein tyrosine kinases, G protein-coupled receptors as well as cytokine receptors. Participates in signaling pathways that control a diverse spectrum of biological activities including gene transcription, immune response, cell adhesion, cell cycle progression, apoptosis, migration, and transformation. Due to functional redundancy between members of the SRC kinase family, identification of the specific role of each SRC kinase is very difficult. SRC appears to be one of the primary kinases activated following engagement of receptors and plays a role in the activation of other protein tyrosine kinase (PTK) families. Receptor clustering or dimerization leads to recruitment of SRC to the receptor complexes where it phosphorylates the tyrosine residues within the receptor cytoplasmic domains. Plays an important role in the regulation of cytoskeletal organization through phosphorylation of specific substrates involved in this process. When cells adhere via focal adhesions to the extra-cellular matrix, signals are transmitted by integrins into the cell and result in tyrosine phosphorylation of a number of focal adhesion proteins, including PTK2/FAK1 and paxillin (PXN). Also active at the sites of cell-cell contact adherens junctions and at gap junctions. Implicated in the regulation of pre-mRNA-processing. Might be involved not only in mediating the transduction of mitogenic signals at the level of the plasma membrane but also in controlling progression through the cell cycle via interaction with regulatory proteins in the nucleus.^{[3] [4]}

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

See Also

• Tyrosine kinase

References

1. ↑ Bergman M, Mustelin T, Oetken C, Partanen J, Flint NA, Amrein KE, Autero M, Burn P, Alitalo K. The human p50csk tyrosine kinase phosphorylates p56lck at Tyr-505 and down regulates its catalytic activity. EMBO J. 1992 Aug;11(8):2919-24. PMID:1639064
2. ↑ Sun G, Budde RJ. Expression, purification, and initial characterization of human Yes protein tyrosine kinase from a bacterial expression system. Arch Biochem Biophys. 1997 Sep 1;345(1):135-42. PMID:9281320 doi:10.1006/abbi.1997.0236
3. ↑ Kremer NE, D'Arcangelo G, Thomas SM, DeMarco M, Brugge JS, Halegoua S. Signal transduction by nerve growth factor and fibroblast growth factor in PC12 cells requires a sequence of src and ras actions. J Cell Biol. 1991 Nov;115(3):809-19. PMID:1717492
4. ↑ Simonson MS, Wang Y, Herman WH. Nuclear signaling by endothelin-1 requires Src protein-tyrosine kinases. J Biol Chem. 1996 Jan 5;271(1):77-82. PMID:8550628
5. ↑ Levinson NM, Seeliger MA, Cole PA, Kuriyan J. Structural basis for the recognition of c-Src by its inactivator Csk. Cell. 2008 Jul 11;134(1):124-34. PMID:18614016 doi:10.1016/j.cell.2008.05.051