Discrete region of the insulin receptor carboxyl terminus plays key role in insulin action.
In the present study, we attempted to determine the importance of a 23-amino-acid sequence within the carboxyl terminus of the human insulin receptor (IR) molecule in modulating insulin action in Chinese hamster ovary cells. Stable expression of a minigene encoding the receptor fragment led to an increase in insulin-induced IR autophosphorylation that was 2.4-fold higher when compared to that of IR-expressing cells transfected with empty vector. Insulin-stimulated downstream signaling was also significantly elevated in cells expressing the minigene. It was found that expression of the minigene had no effect toward insulin-like growth factor I receptor kinase activity and function. These results indicate that the IR carboxyl terminus contains a motif that acts as a physiologic modulator of insulin signaling. J. Cell. Biochem. 78:160-169, 2000. Published 2000 Wiley-Liss, Inc.
Bernier
M
M
Diabetes Section, Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224-2780, USA. Bernierm@vax.grc.nia.nih.gov
Kole
H K
HK
Montrose-Rafizadeh
C
C
Kole
S
S
D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D006801:Humans; D007328:Insulin / Q000502:physiology*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D007700:Kinetics; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation; D011972:Receptor, Insulin / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D014162:Transfection
D007328:Insulin; D010446:Peptide Fragments; D011994:Recombinant Proteins; D007334:Insulin-Like Growth Factor I; D019869:Phosphatidylinositol 3-Kinases; D011972:Receptor, Insulin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases