Insulin receptor structure and its implications for the IGF-1 receptor

Curr Opin Struct Biol. 2007 Dec;17(6):699-705. doi: 10.1016/ Epub 2007 Sep 11.


The insulin receptor (isoforms IR-A and IR-B) and the type-I insulin-like growth factor receptor (IGF-1R) are homologous, multi-domain tyrosine kinases that bind insulin and IGF-1 with differing specificity. IR is involved in metabolic regulation and IGF-1R in normal growth and development. IR-A also binds IGF-2 with an affinity comparable to IGF-1R and, like the latter, is implicated in a range of cancers. The recent structure of the IR ectodomain dimer explains many features of ligand-receptor binding and provides insight into the structure of the intact ligand-binding site in both receptors. The structures of the L1-CR-L2 fragments of IR and IGF-1R reveal major differences in the regions that govern ligand specificity. The IR ectodomain X-ray structure raises doubts about that obtained by STEM reconstruction.

Publication types

  • Review

MeSH terms

  • Animals
  • Humans
  • Ligands
  • Models, Molecular
  • Protein Conformation
  • Receptor, IGF Type 1 / chemistry*
  • Receptor, IGF Type 1 / metabolism
  • Receptor, Insulin / chemistry*
  • Receptor, Insulin / metabolism


  • Ligands
  • Receptor, IGF Type 1
  • Receptor, Insulin