Rabbit polyclonal antibody to IRS~1 (Ser794)

Insulin receptor substrate 1 (IRS~1) is one of the major substrates of the insulin receptor kinase. IRS~1 contains multiple tyrosine phosphorylation motifs that serve as docking sites for SH2~domain containing proteins that mediate the metabolic and growth~promoting functions of insulin. IRS~1 also contains over 30 potential serine/threonine phosphorylation sites. Ser307 of IRS~1 is phosphorylated by JNK and IKK while Ser789 is phosphorylated by SIK~2, a member of the AMPK family. The PKC and mTOR pathways mediate phosphorylation of IRS~1 at Ser612 and Ser636/639, respectively. Phosphorylation of IRS~1 at Ser1101 is mediated by PKCθ and results in an inhibition of insulin signaling in the cell, suggesting a potential mechanism for insulin resistance in some models of obesity.