Reduction of disulfides by thioredoxin. Exceptional reactivity of insulin and suggested functions of thioredoxin in mechanism of hormone action.
Year: 1979
Type: article
Abstract: with insulin disulfides was estimated from fluorescence measurements and the enzymatic rates to be around 1 X 10’ M-’ s-l. This is around 10,000 times higher than the second order rate constant for the reaction between insulin and dithiothreitol, demonstrating the high affinity of insulin for thioredoxin-(SH)z. Nondisulfide oxidants such as Cu2+ ions, diamide, and vitamin KI, which are known to mimic the effects of insulin on cellular hexose transport, were rapidly reduced by the thioredoxin system. The exceptional reactivity of insulin and thioredoxin-(SH)2, in vitro, is consistent with a physiological function for mammalian thioredoxin in the degradation of insulin. Functions for thioredoxin in the “thiol oxidation-reduction model” of insulin action are discussed.
Source: Journal of Biological Chemistry
Author: A. Holmgren
Institution: Karolinska Institutet
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
OpenAlex ID: W2152614869