ERK1 and ERK2 belongs to the protein kinase superfamily. It is involved in both the initiation and regulation of meiosis, mitosis, and postmitotic functions in differentiated cells by phosphorylating a number of transcription factors such as ELK-1. ERK1/2 catalized the reaction: ATP + a protein = ADP + a phosphoprotein. It is activated by tyrosine phosphorylation in response to insulin and NGF. This antibody is specific to ERK1.