Diabetes
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Misbin, R. I.
Right arrow Articles by Almira, E. C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Misbin, R. I.
Right arrow Articles by Almira, E. C.
Social Bookmarking
Add to CiteULike   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

Diabetes, Vol 38, Issue 2 152-158, Copyright © 1989 by American Diabetes Association

ARTICLES

Degradation of insulin and insulin-like growth factors by enzyme purified from human erythrocytes. Comparison of degradation products observed with A14- and B26-[125I]monoiodoinsulin

RI Misbin and EC Almira
Division of Endocrinology and Metabolism, University of Florida College of Medicine, Gainesville 32610.

An insulin-degrading enzyme has been purified from human erythrocytes. This enzyme degraded 125I-labeled insulin-like growth factor I (IGF-I) more slowly than 125I-IGF-II and degraded IGF-II more slowly than 125I-insulin. The time course of 125I-insulin degradation suggested the presence of intermediates, each of which was itself shown to be a substrate for the enzyme. One of these intermediates appeared to be made up entirely of B-chain residues and had HisB10 as its NH2-terminal. The final major radiolabeled degradation product of A14-[125I]monoiodoinsulin was a peptide with TyrA14 at the A-chain NH2 terminal. This peptide could be reduced with dithiothreitol, suggesting that it contained amino acid residues from both A- and B-chains. It was partially precipitated by trichloroacetic acid and anti-insulin antibody but bound poorly to IM-9 lymphocytes. The final major degradation product of B26-[125I]monoiodoinsulin was a peptide whose NH2-terminal was TyrB26 and could not be reduced by dithiothreitol. It was partially precipitated by anti-insulin antibody but was precipitated poorly, if at all, by trichloroacetic acid and bound poorly to IM-9 lymphocytes. The results show that this enzyme degraded insulin by sequential cleavage of peptide bonds on both A- and B-chains. We identified LeuA13-TyrA14, SerB9-HisB10, and PheB25-TyrB26 as three of the bonds that are cleaved.
Add to CiteULike CiteULike   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:


Home page
 Exp. Biol. Med.Home page
D. P. Udrisar, M. I. Wanderley, R. C. C. Porto, C. L. P. Cardoso, M. C. L. Barbosa, M. C. Camberos, and J. C. Cresto
Androgen- and Estrogen-Dependent Regulation of Insulin-Degrading Enzyme in Subcellular Fractions of Rat Prostate and Uterus
Experimental Biology and Medicine, July 1, 2005; 230(7): 479 - 486.
[Abstract] [Full Text] [PDF]

Home page
 Endocr. Rev.Home page
W. C. Duckworth, R. G. Bennett, and F. G. Hamel
Insulin Degradation: Progress and Potential
Endocr. Rev., October 1, 1998; 19(5): 608 - 624.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Diabetes Diabetes Care Clinical Diabetes Diabetes Spectrum
Copyright © 1989 by the American Diabetes Association.