Insulin‐like growth factor I binding and receptor kinase in red and white muscle

FEBS Letters

James, David E.²  Zorzano, Antonio¹  Pilch, Paul F.²  Ruderman, Neil B.² 

[1] Departamento de Bioquímica y Fisiologia, Facultad de Biología, Universidad de Barcelona, Barcelona, Spain;Department of Biochemistry, Boston University School of Medicine Division of Diabetes and Metabolism and Department of Medicine (University Hospital), Boston University School of Medicine, Boston, MA 02118, USA

关键词: IGF-I receptor;    Tyrosine kinase;    (Skeletal muscle;    Rat);    IGF-I;    insulin-like growth factor I;    WGA;    agarose-bound wheat germ agglutinin;    SDS-PAGE;    SDS-polyacrylamide gel electrophoresis;    BSA;    bovine serum albumin;   

DOI  :  10.1016/0014-5793(88)80093-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

IGF-I receptors were partially purified from red and white skeletal muscle by lectin-affinity chromatography and the resultant fraction was depleted of insulin receptors by insulin affinity chromatography. Equilibrium binding of ¹²⁵I-IGF-I to receptor preparations from red and white muscle yielded identical Scatchard plots. The integrity of the IGF-I receptor preparation in the two fiber types was identical as determined by affinity cross-linking. The tyrosine kinase activity of the receptor from red muscle was 2–3-fold more active towards exogenous substrates in both the basal and ligand-activated states as compared to white muscle. These data show that there is IGF-I-dependent kinase activity intrinsic to IGF-I receptors from skeletal muscle, and suggest that identical cellular factors may regulate the kinase activity of insulin and IGF-I receptors in a parallel manner in vivo.

【 授权许可】

Unknown