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Insulin and insulin-like growth factor I receptors: similarities and differences in signal transduction

J Dupont1, D LeRoith

  • 1Clinical Endocrinology Branch, NIDDK, Bethesda, Md 20892-1758, USA.

Hormone Research
|October 31, 2001
PubMed

The insulin receptor (IR) and the insulin-like growth factor I receptor (IGF-IR) belong to the same subfamily of receptor tyrosine kinases with two extracellular alpha-subunits and two transmembrane beta-subunits. They share a high similarity of structure and intracellular signalling events. However, the IR and the IGF-IR mediate different effects on metabolism, cell proliferation, apoptosis and differentiation. Although some of the variation can be attributed to a different tissue distribution or subcellular localization, it can also be explained by structural differences in the beta-subunit, which may result in activation of specific substrates and signal pathways.

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