The biological effects of insulin are mediated by insulin receptor (IR) and IGF-1 receptor. Insulin receptor consists of two α and two β subunits, each subunit has a tyrosine kinase domain. Signaling by IR is important in cell proliferation and metabolism of glucose. Insulin receptor activates the PI3K/Akt and the FKHR pathway, thereby regulates metabolism and insulin-dependent gene expression. Tyrosine 972 is an autophosphorylation site that is present in the juxtamembrane domain. Phosphorylation at Tyr972 is required for interaction of IR with its intracellular substrates and increases the stability of IR and substrate complexes. Overexpression of IR has been observed in breast cancer tissue and is implicated in proliferation of breast cancer cells, hyperinsulinemia and insulin resistance. IR can also bind IGF-I and IGF-II with decreased affinity
Anti-phospho-IR (pTyr972) recognizes human and mouse IR phosphorylated on tyrosine 972. It may cross react with IGF-1R.
