Phospho-Paxillin (Tyr31) Antibody detects endogenous levels of Paxillin only when phosphorylated at Tyrosine 31. PXN is a multi-domain cytoskeletal protein that localizes primarily to focal adhesion sites to the extracellular matrix. Phosphorylated by focal adhesion kinase (FAK) and is a component of integrin signaling. Its phosphorylation provides docking sites for recruitment of signaling molecules to focal adhesions.