IRS-1 (Insulin Receptor Substrate 1) (APC)

IRS1 (Insulin Receptor Substrate 1) transmits insulin signals via metabolic and mitogenic pathways. IRS1 is heavily phosphorylated on both serine and tyrosine residues. These phosphorylated tyrosines enable IRS to act as a docking protein that binds SH2 domains of such proteins as PI3 Kinase (phosphatidylinositol 3-kinase) and GRB2, resulting in activation. Over expression and phosphorylation of serine is associated with insulin resistance and breast cancer. Some of the more notable phosphorylation sites are Ser302 that is phosphorylated following insulin stimulation. Ser307, phosphorylated by...