Phospho-Histone H2A.X (Ser139) Polyclonal antibody

The histone variant H2AX is a major component of the DNA damage response (DDR), especially functioning in amplifying DNA damage signals. In response to DNA double-strand breaks (DSBs), H2AX is instantaneously phosphorylated at Ser140 (a form called cH2AX) by the kinases ATM and ATR and is progressively dephosphorylated at Tyr143 by the Eya1 and Eya3 tyrosine phosphatases, resulting in a temporal switch from a postulated diphosphorylated (pSer140, pTyr143) to monophosphorylated (pSer140) H2AX state. Because phosphorylation of H2AX at Ser 140 (γ-H2AX) is abundant, fast, and correlates well with each DSB, it is the most sensitive marker that can be used to examine the DNA damage produced and the subsequent repair of the DNA lesion. The phosphorylation site of H2AX, Ser140, has also been described as Ser139 in other literature, and they recognize the same amino acid site. (PMID: 22908299, PMID: 17615256, PMID:22941631)