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: Protein kinase, tyrosine (non-receptor); Protein kinase, TK; Kinase, protein; EC 22.214.171.124; TK group; Src family
Cellular Component: extrinsic to internal side of plasma membrane; membrane; intracellular membrane-bound organelle; mitochondrion; postsynaptic density; cytoplasm; plasma membrane; actin filament; nucleus; endosome; lipid raft
Molecular Function: tubulin binding; CD8 receptor binding; ephrin receptor binding; metal ion binding; non-membrane spanning protein tyrosine kinase activity; nucleotide binding; protein kinase activity; transferase activity; protein binding; peptide hormone receptor binding; G-protein-coupled receptor binding; protein-tyrosine kinase activity; transferase activity, transferring phosphorus-containing groups; protein complex binding; T cell receptor binding; phosphoinositide 3-kinase binding; kinase activity; glycoprotein binding; CD4 receptor binding; ATP binding; receptor binding
Biological Process: myelination; positive regulation of I-kappaB kinase/NF-kappaB cascade; peptidyl-tyrosine phosphorylation; immune system process; dendrite morphogenesis; multicellular organismal development; protein amino acid autophosphorylation; neuron migration; activated T cell proliferation; protein amino acid phosphorylation; T cell receptor signaling pathway; regulation of cell proliferation; positive regulation of phosphoinositide 3-kinase cascade; regulation of apoptosis; detection of mechanical stimulus involved in sensory perception of pain; regulation of cell shape; cell surface receptor linked signal transduction; response to ethanol; forebrain development; innate immune response; negative regulation of neuron apoptosis; negative regulation of protein catabolic process; phosphorylation; 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.