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: EC 18.104.22.168; Kinase, protein; Oncoprotein; Protein kinase, TK; Protein kinase, tyrosine (non-receptor); Src family; TK group
Cellular Component: actin filament; cytosol; dendrite; endosome; extrinsic to internal side of plasma membrane; intracellular membrane-bound organelle; lipid raft; membrane; mitochondrion; plasma membrane; postsynaptic density
Molecular Function: CD4 receptor binding; CD8 receptor binding; enzyme binding; ephrin receptor binding; G-protein-coupled receptor binding; glycoprotein binding; identical protein binding; non-membrane spanning protein tyrosine kinase activity; peptide hormone receptor binding; phosphoinositide 3-kinase binding; protein binding; protein complex binding; protein kinase activity; protein-tyrosine kinase activity; receptor binding; signal transducer activity; T cell receptor binding; tubulin binding
Biological Process: activated T cell proliferation; cell surface receptor linked signal transduction; dendrite morphogenesis; detection of mechanical stimulus involved in sensory perception of pain; forebrain development; innate immune response; myelination; negative regulation of neuron apoptosis; negative regulation of protein catabolic process; negative regulation of protein ubiquitination; neuron migration; peptidyl-tyrosine phosphorylation; positive regulation of I-kappaB kinase/NF-kappaB cascade; positive regulation of phosphoinositide 3-kinase cascade; positive regulation of tyrosine phosphorylation of STAT protein; protein amino acid autophosphorylation; protein amino acid phosphorylation; regulation of apoptosis; regulation of cell proliferation; regulation of cell shape; regulation of peptidyl-tyrosine phosphorylation; response to ethanol; T cell receptor signaling pathway; transmembrane receptor protein tyrosine kinase signaling pathway