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Science 11 November 1977:
Vol. 198. no. 4317, pp. 620 - 622
DOI: 10.1126/science.918657
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Articles

Science, Vol 198, Issue 4317, 620-622
Copyright © 1977 by American Association for the Advancement of Science

articles

Cell-free modulation of proinsulin synthesis

PT Lomedico and GF Saunders

In vivo, glucose preferentially stimulates proinsulin biosynthesis; at least part of this process is independent of new RNA synthesis and is accompanied by increases in the overall rate of polypeptide chain initiation. The cell-free translation of proinsulin messenger RNA is very sensitive to changes in the protein-synthesizing system. Proinsulin synthesis is preferentially inhibited by the addition of increasing quantities of polyadenylate-containing RNA from the fetal bovine pancreas or by the addition of the drug, aurintricarboxylic acid, which blocks polypeptide chain initiation. These results suggest that proinsulin messenger RNA completes less efficiently for rate controlling initiation factors. We propose that glucose stimulates proinsulin biosynthesis by allowing the less competitive proinsulin messenger RNA to be translated more efficiently.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Glucose Stimulates the Activity of the Guanine Nucleotide-exchange Factor eIF-2B in Isolated Rat Islets of Langerhans.
M. Gilligan, G. I. Welsh, A. Flynn, I. Bujalska, T. A. Diggle, R. M. Denton, C. G. Proud, and K. Docherty (1996)
J. Biol. Chem. 271, 2121-2125
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