The signalling in T cells is mediated by receptor and non-receptor protein tyrosine kinases (PTK). Among the family of non-receptors PTK, Lck is a lymphoid-specific cytosolic PTK essential for T-cell development and function. Lck is essential for selection and maturation of developing T cells in the thymus. It plays a significant role in T-cell receptors mediated signalling by constitutive association with CD4 and CD8 receptors. In addition, Lck undergoes phosphorylation and activation by association with CD2 molecule. Lck also plays a role in T-cell proliferation in response to IL-2 receptor pathway. The activity of Lck is known to be regulated by phosphorylation of two conserved tyrosine residues, tyrosine 505 (equivalent to tyrosine 529 in c-Src) and tyrosine 394 (equivalent to tyrosine 418 in c-Src). Phosphorylation at Tyr505 stabillizes Lck and renders it biologically inactive.
Anti-phospho Lck (pTyr505) specifically recognizes human Lck (pTyr505). Mouse (100% homology) and chicken (91.7% homology) are expected to react.
