cd05060: PTKc_Syk_like (this model, PSSM-Id:133191 is obsolete and has been replaced by 270650)
Catalytic domain of Spleen Tyrosine Kinase-like Protein Tyrosine Kinases
Protein Tyrosine Kinase (PTK) family; Spleen Tyrosine Kinase (Syk) subfamily; catalytic (c) domain. The Syk subfamily is composed of Syk, ZAP-70, Shark, and similar proteins. The PTKc family is part of a larger superfamily that includes the catalytic domains of other kinases such as protein serine/threonine kinases, RIO kinases, and phosphoinositide 3-kinase (PI3K). PTKs catalyze the transfer of the gamma-phosphoryl group from ATP to tyrosine (tyr) residues in protein substrates. Syk subfamily kinases are cytoplasmic (or nonreceptor) tyr kinases containing two Src homology 2 (SH2) domains N-terminal to the catalytic tyr kinase domain. They are involved in the signaling downstream of activated receptors (including B-cell, T-cell, and Fc receptors) that contain ITAMs (immunoreceptor tyr activation motifs), leading to processes such as cell proliferation, differentiation, survival, adhesion, migration, and phagocytosis. Syk is important in B-cell receptor (BCR) signaling, while Zap-70 is primarily expressed in T-cells and NK cells, and is a crucial component in T-cell receptor (TCR) signaling. Syk also plays a central role in Fc receptor-mediated phagocytosis in the adaptive immune system. Shark is exclusively expressed in ectodermally derived epithelia, and is localized preferentially to the apical surface of the epithelial cells, it may play a role in a signaling pathway for epithelial cell polarity.
Comment:Based on the structures of other PTK family members bound to substrate peptides and ATP analogs as well as, the structures of human Syk tyr kinase and human Zap-70 tyr kinase bound with the inhibitor, staurosporine
Jiyao W et al.(2023). "The conserved domain database in 2023.",