The insulin receptor is a complex multifunctional protein located on thecell surface within the fluid mosaic matrix of the plasma membrane. Its ability to bind insulin is determinedby structural and spatial specificity, high affinity and reversibility. Insulin action at the cellularlevel can be considered in three stages. The first stage includes the insulin receptor itself, the insulinsubstrate (IRS-1) and the molecules that interact with IRS-1. The second stage is that of cascade phosphorylationand dephosphorylation. The third stage concerns the final biological effects of the insulin cascade.The biological specificity of insulin binding and heterogeneity of insulin action in different cellshas been well documented. This review intends to summarize the available data of structural and functionalcharacteristics of insulin receptor.

Keywords: insulin receptor, binding kinetics, biological effect