Rabbit Anti-Human FAK2 (phospho Tyr402) monoclonal antibody for ChIP, WB. PyK2, also known as protein tyrosine kinase, is known to be expressed in the central nervous system and from cells derived from hematopoietic lineages. In response to various stimuli that increase the intracellular calcium concentration, PyK2 gets rapidly phosphorylated on the tyrosine residues. On activation of the Pyk2 protein, the MAP kinase signaling pathway is activated and its activation brings about modulation of the ion channel function. The phosphorylation of tyrosin is brought about by reactions involving protein tyrosine phosphatases and the RAFT/Pyk2 kinase proteins.