IGF-1R
Transmembrane tyrosine-kinase receptor for IGF-1, structurally related to the insulin receptor.
For laboratory and research use only — not for human consumption.
The type-1 IGF receptor (IGF-1R) is a heterotetrameric transmembrane tyrosine kinase composed of two extracellular α-subunits and two transmembrane β-subunits, with strong (~60%) sequence homology to the insulin receptor. Ligand binding to the α-subunits triggers autophosphorylation of intracellular tyrosines on the β-subunits, recruiting insulin-receptor-substrate proteins (IRS-1, IRS-2) and SHC, which in turn activate two principal downstream cascades: the PI3K/Akt/mTOR pathway (driving protein synthesis, cell survival, and metabolic effects) and the Ras/Raf/MAPK pathway (driving proliferation). IGF-1R is widely expressed across tissues and is the principal receptor through which IGF-1 produces its anabolic effects on muscle, tendon, cartilage, and bone. Hybrid receptors composed of insulin-receptor and IGF-1R hemireceptors exist and have intermediate ligand affinities. IGF-1R is mechanistically central to growth-hormone-secretagogue research (where GH-driven IGF-1 elevation is the downstream effector) and to tendon-healing peptide research (where BPC-157's reported effects on tenocyte growth-hormone receptor expression converge on the IGF-1/IGF-1R axis). Pharmacological IGF-1R inhibitors are developed primarily for oncology applications, not for healing research.