Insulin receptor: Regulate glucose homeostasis

The insulin receptor is a member of the ligand-activated receptor and tyrosine kinase family of transmembrane signaling proteins. The insulin receptor is a cell surface integral membrane protein present in most mammalian cells. The receptor recognizes and binds insulin; the strength of the insulin signal transduced is a function of the concentration of the insulin receptor complex.

The insulin receptor is a 350,000-kDa transmembrane glycoprotein comprise of two α (125 to 135 kDa on SDS gels) and two β (95 kDa) subunits, linked through disulfide-linked oligomer.

Signal transduction through the insulin receptor appears to require the activation of an intrinsic tyrosine-specific protein kinase activity.

Mammalian cells express 100 to 250,000 receptors on their cell surface. Cells expressing the highest number of receptors, i.e., adipose, muscle, and liver cells, are the more responsive to insulin and indeed function as mediators of most of insulin's metabolic effects.

The insulin receptor (IR) has a pivotal role in the regulation of glucose homeostasis, and its dysfunction can result in a range of clinical manifestations, including diabetes mellitus and cancer.
Insulin receptor: Regulate glucose homeostasis