Recombinant human insulin-like growth factor (IGF)-binding protein-6 inhibits IGF-II-induced differentiation of L6A1 myoblasts

Endocrinology
L A BachM M Rechler

Abstract

Insulin-like growth factor-binding protein-6 (IGFBP-6) is an O-linked glycoprotein that binds insulin-like growth factor-II (IGF-II) with marked preferential affinity over IGF-I. Recombinant human IGFBP-6 (rhIGFBP-6) was synthesized by COS-7 monkey kidney cells that were transiently transfected with a eukaryotic expression vector into which a complementary DNA for IGFBP-6 modified for optimal translation had been inserted. rhIGFBP-6 was similar to IGFBP-6 purified from human cerebrospinal fluid with respect to IGF binding and O-glycosylation. The effect of rhIGFBP-6 on IGF-induced L6A1 myoblast differentiation was studied using creatine kinase activity as an index of differentiation. rhIGFBP-6 inhibited differentiation initiated by IGF-II in a dose-dependent manner, inhibition was complete when rhIGFBP-6 was present in a slight molar excess. In contrast, rhIGFBP-6 had no effect on IGF-I-induced differentiation, even when coincubated in a 5-fold molar excess. These results are consistent with the preferential affinity of IGFBP-6 for IGF-II. As cell association and proteolysis have been associated with the potentiation, rather than the inhibition, of IGF action by IGFBPs, we investigated whether they occurred in the L6A1 myoblast...Continue Reading

Citations

Dec 5, 1995·Proceedings of the National Academy of Sciences of the United States of America·H D UlrichP G Schultz
May 28, 1996·Proceedings of the National Academy of Sciences of the United States of America·L C Hsieh-WilsonR C Stevens
Sep 1, 1996·Endocrinology and Metabolism Clinics of North America·P F Collett-Solberg, P Cohen
Aug 28, 1998·Bioscience, Biotechnology, and Biochemistry·J AikawaT Ogawa
Dec 18, 2001·International Journal of Cancer. Journal International Du Cancer·M A GallicchioL A Bach
Jul 1, 1997·Journal of Cellular Biochemistry·B Gabbitas, E Canalis
Aug 1, 1996·Canadian Journal of Applied Physiology = Revue Canadienne De Physiologie Appliquée·J MacGregor, W S Parkhouse
May 29, 2000·American Journal of Physiology. Endocrinology and Metabolism·R C Baxter
Mar 7, 1997·The Journal of Biological Chemistry·S A CoolicanJ R Florini
Nov 1, 1995·The American Journal of Physiology·R J UrbanA Ferrando
Oct 21, 1999·Molecular Genetics and Metabolism·L A WetterauP Cohen
Mar 27, 2002·Growth Hormone & IGF Research : Official Journal of the Growth Hormone Research Society and the International IGF Research Society·T YanD D Strong
Oct 12, 2002·European Journal of Cancer : Official Journal for European Organization for Research and Treatment of Cancer (EORTC) [and] European Association for Cancer Research (EACR)·D SeurinS Babajko

❮ Previous
Next ❯

Related Concepts

Related Feeds

CSF & Lymphatic System

This feed focuses on Cerebral Spinal Fluid (CSF) and the lymphatic system. Discover the latest papers using imaging techniques to track CSF outflow into the lymphatic system in animal models.