Insulin receptor substrate (IRS) transduction system: distinct and overlapping signaling potential

Insulin receptor substrate (IRS) proteins play a central role in maintainin g basic cellular functions such as growth and metabolism. They act as an in terface between multiple growth factor receptors possessing tyrosine kinase activity, such as the insulin receptor, and a complex network of intracell ular signalling molecules containing Src homology 2 (SH2) domains. Four mem bers (IRS-1, IRS-2, IRS-3, IRS-4) of this family have been identified which differ in their subcellular distribution and interaction with SH2 domain p roteins. In addition, differential IRS tissue- and developmental-specific e xpression patterns may contribute to specificity in their signaling potenti al. Copyright (C) 2000 John Wiley & Sons, Ltd.