Insulin-like growth factor (IGF) are proteins with high sequence similarity to insulin. IGF are ligands in a complex called the IGF axis, which contains 2 IGF receptors, 6 IGF-binding proteins and IGF-binding protein degrading enzyme. IGF I is secreted in the liver after stimulation by growth hormone. IGF II is required in early development stages.
3D structures of insulin-like growth factor
IGF I
2gfr, 3gf1, 1b9g, 1bqt – hIGF I – human – NMR
3lri - hIGF I (mutant) – NMR
1tgr - hIGF I (mutant)
1imx, 1gzr, 1gzy, 1gzz, 1gzr, 1h02 - hIGF I
1pmx – hIGF I + peptide - NMR
1h59 – hIGF I + IGF binding protein 5
2dsp, 2dsr - hIGF I + IGF binding protein 4
2dsq - hIGF I + IGF binding protein 4 + IGF binding protein 1
IGF II
1igl - hIGF II – NMR
3e4z – hIGF II + insulin-degrading enzyme
3rk3 – hIGF II + antibody
