Structural analyses of a constitutively active mutant of exchange protein directly activated by cAMP.

Exchange proteins directly activated by cAMP (EPACs) are important allosteric regulators of cAMP-mediated signal transduction pathways. To understand the molecular mechanism of EPAC activation, we have combined site-directed mutagenesis, X-ray crystallography, and peptide amide hydrogen/deuterium ex...

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Bibliographic Details
Main Authors: Mark A White, Sheng Li, Tamara Tsalkova, Fang C Mei, Tong Liu, Virgil L Woods, Xiaodong Cheng
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2012-01-01
Series:PLoS ONE
Online Access:https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23189173/?tool=EBI
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Summary:Exchange proteins directly activated by cAMP (EPACs) are important allosteric regulators of cAMP-mediated signal transduction pathways. To understand the molecular mechanism of EPAC activation, we have combined site-directed mutagenesis, X-ray crystallography, and peptide amide hydrogen/deuterium exchange mass spectrometry (DXMS) to probe the structural and conformational dynamics of EPAC2-F435G, a constitutively active EPAC2 mutant. Our study demonstrates that conformational dynamics plays a critical role in cAMP-induced EPAC activation. A glycine mutation at 435 position shifts the equilibrium of conformational dynamics towards the extended active conformation.
ISSN:1932-6203