Reactome: A Curated Pathway Database

Insulin binds the insulin receptor (R-HSA-74716)

Species Homo sapiens

Summation

Under normal physiological conditions blood glucose levels are kept under tight control by a series of regulated steps that ensure glucose homeostasis. Upon feeding glucose levels rise and in response to this the body secretes insulin from pancreatic beta-cells into the blood. At physiological concentrations insulin is present in the blood in its monomeric form. The insulin receptor is a tetramer, consisting of two alpha and two beta chains, which are produced by cleavage of a single translated peptide chain (Schenker & Kohanski 1991). Binding of insulin to its receptor occurs on the receptor alpha-subunits. There are two binding domains involved on the receptor (L1 and L2) and it is thought that the amino-terminus of insulin binds with L1 on one of the alpha-subunits and the carboxyterminus with L2 on the other alpha-subunit.

The binding of insulin to its receptor causes a conformational change in the alpha-subunits. This in turn produces a conformational change in the beta-subunits leading to the activation of the intrinsic insulin receptor tyrosine kinase.

Locations in the PathwayBrowser
Additional Information
Compartment external side of plasma membrane
Literature References
pubMedId Title Journal Year
7781591 Insulin action and the insulin signaling network. Endocr Rev 1995
8276779 The insulin signaling system. J Biol Chem 1994
11737239 Surfing the insulin signaling web. Eur J Clin Invest 2001