Species predicted to react based on 100% sequence homology:Mouse, Rat, Hamster, Monkey, Chicken, Bovine, Dog, Pig, Horse
Specificity / Sensitivity
Phospho-Zap-70 (Tyr319)/Syk (Tyr352) Antibody detects endogenous levels of Zap-70 only when phosphorylated at Tyr319. It cross-reacts with endogenous levels of Syk when phosphorylated at Tyr352.
Source / Purification
Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Tyr319 of human Zap-70. Antibodies are purified by protein A and peptide affinity chromatography.
Background
The Syk family protein tyrosine kinase Zap-70 is expressed in T and NK cells and plays a critical role in mediating T cell activation in response to T cell receptor (TCR) engagement (1). Following TCR engagement, Zap-70 is rapidly phosphorylated on several tyrosine residues through autophosphorylation and transphosphorylation by the Src family tyrosine kinase Lck (2-6). Tyrosine phosphorylation correlates with increased Zap-70 kinase activity and downstream signaling events. Expression of Zap-70 is correlated with disease progression and survival in patients with chronic lymphocytic leukemia (7,8).Phosphorylation of Tyr319 is required for the assembly of a Zap-70-containing signaling complex that leads to the activation of the PLC-gamma1-dependent and Ras-dependent signaling cascades in antigen-stimulated T cells (5,6). The orthologous Tyr352 residue in Syk is also involved in the association with PLC-gamma1 (9).