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Updated: Aug 19, 2026

Oligopeptide Competition Assay for Phosphorylation Site Determination
Published on: May 18, 2017
Signal transduction by MAP kinases: regulation by phosphorylation-dependent switches
1Howard Hughes Medical Institute, Program in Molecular Medicine, Department of Biochemistry, University of Massachusetts Medical School, Worcester, MA 01605 USA. roger.davis@umassmed.edu
Abstract:
The kinases of mitogen-activated protein (MAP) kinase cascades transmit signals through sequential phosphorylation and activation of the enzymes. However, recent evidence indicates that protein-protein interactions between the kinases themselves or with substrates or other components are also a critical means of regulation. Whitmarsh and Davis summarize these findings with emphasis on new evidence from yeast that, when phosphorylated, a MAP kinase kinase actually switches from a negative regulator that binds to and inhibits its target MAP kinase to a positive regulator of that same enzyme.
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