Signaling via the IRS proteins. The IRS proteins are recruited to activated cell surface receptors via PH/PTB domains in their N-termini. Once bound, they are phosphorylated on tyrosine residues in their C-termini. The phosphorylation of tyrosine residues (pY) creates docking sites for the recruitment of downstream signaling effectors. Subsequently, signaling cascades are activated that can regulate gene expression, protein synthesis, glycolysis, cell proliferation, survival and motility/invasion.