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Structural basis for phosphorylation and lysine acetylation cross-talk in a kinase motif associated with myocardial ischemia and cardioprotection
Parker, Benjamin L. Shepherd, Nicholas E. Trefely, Sophie Hoffman, Nolan John White, Melanie Y. Engholm-Keller, Kasper Hambly, Brett D. Larsen, Martin R. James, David E. Cordwell, Stuart J.
Parker, Benjamin L.
Shepherd, Nicholas E.
Trefely, Sophie
Hoffman, Nolan John
White, Melanie Y.
Engholm-Keller, Kasper
Hambly, Brett D.
Larsen, Martin R.
James, David E.
Cordwell, Stuart J.
Abstract
Myocardial ischemia and cardioprotection by ischemic pre-conditioning induce signal networks aimed at survival or cell death if the ischemic period is prolonged. These pathways are mediated by protein post-translational modifications that are hypothesized to cross-talk with and regulate each other. Phosphopeptides and lysine-acetylated peptides were quantified in isolated rat hearts subjected to ischemia or ischemic pre-conditioning, with and without splitomicin inhibition of lysine deacetylation. We show lysine acetylation (acetyl-Lys)-dependent activation of AMP-activated protein kinase, AKT, and PKA kinases during ischemia. Phosphorylation and acetyl-Lys sites mapped onto tertiary structures were proximal in >50% of proteins investigated, yet they were mutually exclusive in 50 ischemic pre-conditioning- and/or ischemia-associated peptides containing the KXXS basophilic protein kinase consensus motif. Modifications in this motif were modeled in the C terminus of muscle-type creatine kinase. Acetyl-Lys increased proximal dephosphorylation by 10-fold. Structural analysis of modified muscle-type creatine kinase peptide variants by two-dimensional NMR revealed stabilization via a lysine-phosphate salt bridge, which was disrupted by acetyl-Lys resulting in backbone flexibility and increased phosphatase accessibility.
Keywords
Date
2014
Type
Journal article
Journal
Journal of Biological Chemistry
Book
Volume
289
Issue
37
Page Range
25890-25906
Article Number
ACU Department
Centre for Exercise and Nutrition
Faculty of Health Sciences
Faculty of Health Sciences
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Relation URI
Source URL
Event URL
Open Access Status
Open access
License
File Access
Controlled