Receptor-Mediated Internalization and Turnover

Binding of insulin to its specific cell surface receptor initiates a complicated array of events which encompass a variety of biochemical and physical steps. These include the generation of insulin’s pleiotropic biologic effects, as well as endocytotic uptake of the hormone-receptor complex. Insulin receptor internalization facilitates the process of hormone degradation and also initiates the steps of receptor uptake, intracellular traffic, and recycling; these latter events can be referred to as the insulin receptor itinerary. We will review some recent findings and the current state of knowledge concerning the insulin receptor itinerary and speculate about its function.