a tyrosine kinase of the Src family. Implicated in the control of cell growth. Plays a role in the regulation of intracellular calcium levels. Required in brain development and mature brain function with important roles in the regulation of axon growth, axon guidance, and neurite extension. Blocks axon outgrowth and attraction induced by NTN1 by phosphorylating its receptor DDC. Associates with the p85 subunit of phosphatidylinositol 3-kinase and interacts with the fyn-binding protein. Three alternatively spliced isoforms have been described. Isoform 2 shows a greater ability to mobilize cytoplasmic calcium than isoform 1. Induced expression aids in cellular transformation and xenograft metastasis. In squamous cell carcinoma, Fyn transduces signals from EGFR and Src and is required for cell migration and invasiveness. Activity linked to migration in a murine melanoma model. Appears to block late stage development of neuroblastoma. Mouse knockout deficient in kindling response, a model for human epilepsy. Note: This description may include information from UniProtKB.
Protein type: Kinase, protein; EC 126.96.36.199; Protein kinase, TK; Protein kinase, tyrosine (non-receptor); TK group; Src family
Chromosomal Location of Human Ortholog: 6q21
Cellular Component: extrinsic to internal side of plasma membrane; mitochondrion; postsynaptic density; plasma membrane; actin filament; cytosol; nucleus; endosome; lipid raft
Molecular Function: tubulin binding; CD8 receptor binding; protein binding; G-protein-coupled receptor binding; ephrin receptor binding; peptide hormone receptor binding; metal ion binding; protein-tyrosine kinase activity; non-membrane spanning protein tyrosine kinase activity; T cell receptor binding; phosphoinositide 3-kinase binding; glycoprotein binding; CD4 receptor binding; ATP binding
Biological Process: axon guidance; central nervous system development; nerve growth factor receptor signaling pathway; T cell activation; viral reproduction; neuron migration; T cell receptor signaling pathway; protein amino acid phosphorylation; regulation of apoptosis; regulation of cell shape; calcium ion transport; forebrain development; ephrin receptor signaling pathway; feeding behavior; negative regulation of neuron apoptosis; cell differentiation; response to drug; epidermal growth factor receptor signaling pathway; platelet activation; cell migration; fibroblast growth factor receptor signaling pathway; positive regulation of I-kappaB kinase/NF-kappaB cascade; phosphoinositide-mediated signaling; dendrite morphogenesis; activated T cell proliferation; learning; regulation of defense response to virus by virus; regulation of cell proliferation; positive regulation of phosphoinositide 3-kinase cascade; detection of mechanical stimulus involved in sensory perception of pain; response to ethanol; T cell costimulation; innate immune response; vascular endothelial growth factor receptor signaling pathway; blood coagulation; negative regulation of protein catabolic process; leukocyte migration; transmembrane receptor protein tyrosine kinase signaling pathway
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.