Insulin-Like Growth Factor

**Semantic type:** Amino Acid, Peptide, or Protein|Hormone

**Definition:** Bound to IGFBPs in the circulation, Insulin-Like Growth Factors (IGFs, Somatomedins) are a family of extracellular signaling peptides (potential autocrine ligands) involved in mediation of growth hormone action, stimulation of insulin action, and growth and development. The three main somatomedins are Somatomedin C (IGF1), Somatomedin A (IGF2), and Somatomedin B. Single chain IGFs I and II share about 47% amino acid homology with insulin (INS) and 31% with relaxin.

**Synonyms:** - IGF - IGF - Somatomedin - insulin-like growth factor - somatomedin