LYN,also named as JTK8,p53Lyn and p56Lyn,belongs to the protein kinase superfamily,Tyr protein kinase family and SRC subfamily. It is a non-receptor tyrosine-protein kinase 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,integrin signaling,but also responses to DNA damage and genotoxic agents. LYN is a component of the mTOR (mammalian target of rapamycin) pathway.