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Updated: Jul 11, 2026

Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells
Published on: June 15, 2013
A proteolytic mechanism for the action of insulin via oligopeptide mediator formation
Abstract:
Evidence is presented that the chemical mediator of insulin action is a peptide(s) and most likely glycopeptide(s). The mediator is formed proteolytically because 1) protease inhibitors inhibit insulin action and 2) trypsin mimicks insulin action via mediator formation. Trypsin mediator does not faithfully reproduce the action of insulin mediator, which indicates that the sites of proteolytic cleavage by insulin and trypsin differ. A coordinated multivalent proteolytic mechanism by which insulin acts to trigger an external membrane-bound protease to cleave mediator from a membrane glycoprotein precursor is presented.
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