title: Different roles of the IGF-I Ec peptide (MGF) and mature IGF-I in myoblast proliferation and differentiation.
abstract: The physiological function of a recently cloned splice variant of insulin-like growth factor-I (IGF-I; mechano growth factor (MGF)) was studied using an in vitro cell model. Unlike mature IGF-I, the distinct E domain of MGF inhibits terminal differentiation whilst increasing myoblast proliferation. Blocking the IGF-I receptor with a specific antibody indicated that the function of MGF E domain is mediated via a different receptor. The results provide a basis for localized tissue adaptation and helps explain why loss of muscle mass occurs in the elderly and in dystrophic muscle in which MGF production is markedly affected.
authors.affiliation: Molecular Tissue Repair Unit, Department of Surgery, Royal Free and University College Medical School, University College London, Rowland Hill Street, UK.
authors.forename: Shi Yu
authors.initials: SY
authors.lastname: Yang
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Goldspink
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000166:cytology*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D017526:Receptor, IGF Type 1 / Q000378:metabolism
chemical_list: D020033:Protein Isoforms; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1