a non-receptor tyrosine-protein kinase of the Src family that transmits signals from cell surface receptors and plays an important role in the regulation of innate and adaptive immune responses, hematopoiesis, responses to growth factors and cytokines, and integrin signaling in B cells, hematopoietic progenitors, platelets, erythrocytes, and in mature myeloid cells, such as dendritic cells, neutrophils and eosinophils. Functions primarily as negative regulator, but can also function as activator, depending on the context. Required for the initiation of the B-cell response, but also for its down-regulation and termination. Plays an important role in the regulation of B-cell differentiation, proliferation, survival and apoptosis, and is important for immune self-tolerance. Acts downstream of several immune receptors, including the B-cell receptor, CD79A, CD79B, CD5, CD19, CD22, CSF2, CXCR4, EPOR, FCER1, FCGR2, FCGR1A, IL3, IL5, TLR2 and TLR4. Acts downstream of KIT, MPL. Regulates cell proliferation, survival, differentiation, migration, adhesion, degranulation, and cytokine release. Down-regulates signaling pathways by phosphorylation of immunoreceptor tyrosine-based inhibitory motifs (ITIM), that then serve as binding sites for phosphatases that modulate signaling. Belongs to the protein kinase superfamily. Tyr protein kinase family. SRC subfamily. Detected in monocytes. placenta, fetal brain, lung, liver and kidney. Widely expressed in a variety of organs, tissues, and cell types such as epidermoid, hematopoietic, and neuronal cells. Expressed in primary neuroblastoma tumors. 2 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: EC 18.104.22.168; Kinase, protein; Oncoprotein; Protein kinase, TK; Protein kinase, tyrosine (non-receptor); Src family; TK group
Molecular Function: ATP binding; ephrin receptor binding; gamma-tubulin binding; glycosphingolipid binding; integrin binding; ion channel binding; kinase activity; non-membrane spanning protein tyrosine kinase activity; phosphoprotein binding; phosphorylation-dependent protein binding; platelet-derived growth factor receptor binding; protein binding; protein tyrosine kinase activity; SH3 domain binding; ubiquitin protein ligase binding
Biological Process: adaptive immune response; B cell homeostasis; B cell receptor signaling pathway; blood coagulation; cellular response to DNA damage stimulus; cellular response to extracellular stimulus; cellular response to heat; cellular response to retinoic acid; cytokine secretion; dendritic cell differentiation; ephrin receptor signaling pathway; erythrocyte differentiation; Fc receptor mediated inhibitory signaling pathway; Fc receptor mediated stimulatory signaling pathway; Fc-epsilon receptor signaling pathway; Fc-gamma receptor signaling pathway involved in phagocytosis; histamine secretion by mast cell; immune response-regulating cell surface receptor signaling pathway; innate immune response; intracellular signal transduction; JAK-STAT cascade involved in growth hormone signaling pathway; leukocyte migration; lipopolysaccharide-mediated signaling pathway; negative regulation of cell proliferation; negative regulation of ERK1 and ERK2 cascade; negative regulation of immune response; negative regulation of intracellular signal transduction; negative regulation of MAP kinase activity; negative regulation of mast cell proliferation; negative regulation of myeloid leukocyte differentiation; negative regulation of protein phosphorylation; negative regulation of toll-like receptor 2 signaling pathway; negative regulation of toll-like receptor 4 signaling pathway; oligodendrocyte development; peptidyl-tyrosine phosphorylation; platelet activation; platelet degranulation; positive regulation of aspartic-type endopeptidase activity involved in amyloid precursor protein catabolic process; positive regulation of cell migration; positive regulation of cell proliferation; positive regulation of cellular component movement; positive regulation of dendritic cell apoptotic process; positive regulation of Fc receptor mediated stimulatory signaling pathway; positive regulation of glial cell proliferation; positive regulation of mast cell proliferation; positive regulation of neuron projection development; positive regulation of oligodendrocyte progenitor proliferation; positive regulation of phosphatidylinositol 3-kinase activity; positive regulation of phosphatidylinositol 3-kinase signaling; positive regulation of protein phosphorylation; positive regulation of Ras protein signal transduction; positive regulation of stress-activated protein kinase signaling cascade; positive regulation of tyrosine phosphorylation of STAT protein; protein autophosphorylation; protein phosphorylation; regulation of B cell receptor signaling pathway; regulation of cell adhesion mediated by integrin; regulation of cytokine production; regulation of cytokine secretion; regulation of ERK1 and ERK2 cascade; regulation of erythrocyte differentiation; regulation of inflammatory response; regulation of mast cell activation; regulation of mast cell degranulation; regulation of monocyte chemotaxis; regulation of platelet aggregation; regulation of protein phosphorylation; regulation of release of sequestered calcium ion into cytosol; response to amino acid; response to axon injury; response to carbohydrate; response to drug; response to hormone; response to insulin; response to organic cyclic compound; response to sterol depletion; response to toxic substance; signal transduction; stimulatory C-type lectin receptor signaling pathway; T cell costimulation; tolerance induction to self antigen; transmembrane receptor protein tyrosine kinase signaling pathway; viral process