Show simple item record Colomer, J Schmitt, AA Toone, EJ Means, AR
dc.coverage.spatial United States 2011-06-21T17:22:09Z 2010-05-18
dc.identifier.citation Biochemistry, 2010, 49 (19), pp. 4244 - 4254
dc.description.abstract We developed a high-throughput yeast-based assay to screen for chemical inhibitors of Ca(2+)/calmodulin-dependent kinase pathways. After screening two small libraries, we identified the novel antagonist 125-C9, a substituted ethyleneamine. In vitro kinase assays confirmed that 125-C9 inhibited several calmodulin-dependent kinases (CaMKs) competitively with Ca(2+)/calmodulin (Ca(2+)/CaM). This suggested that 125-C9 acted as an antagonist for Ca(2+)/CaM rather than for CaMKs. We confirmed this hypothesis by showing that 125-C9 binds directly to Ca(2+)/CaM using isothermal titration calorimetry. We further characterized binding of 125-C9 to Ca(2+)/CaM and compared its properties with those of two well-studied CaM antagonists: trifluoperazine (TFP) and W-13. Isothermal titration calorimetry revealed that binding of 125-C9 to CaM is absolutely Ca(2+)-dependent, likely occurs with a stoichiometry of five 125-C9 molecules to one CaM molecule, and involves an exchange of two protons at pH 7.0. Binding of 125-C9 is driven overall by entropy and appears to be competitive with TFP and W-13, which is consistent with occupation of similar binding sites. To test the effects of 125-C9 in living cells, we evaluated mitogen-stimulated re-entry of quiescent cells into proliferation and found similar, although slightly better, levels of inhibition by 125-C9 than by TFP and W-13. Our results not only define a novel Ca(2+)/CaM inhibitor but also reveal that chemically unique CaM antagonists can bind CaM by distinct mechanisms but similarly inhibit cellular actions of CaM.
dc.format.extent 4244 - 4254
dc.language eng
dc.language.iso en_US en_US
dc.relation.ispartof Biochemistry
dc.relation.isversionof 10.1021/bi1001213
dc.subject Binding Sites
dc.subject Calmodulin
dc.subject Hydrogen-Ion Concentration
dc.subject Substrate Specificity
dc.subject Sulfonamides
dc.subject Trifluoperazine
dc.title Identification and inhibitory properties of a novel Ca(2+)/calmodulin antagonist.
dc.title.alternative en_US
dc.type Journal Article
dc.description.version Version of Record en_US 2010-5-18 en_US
duke.description.endpage 4254 en_US
duke.description.issue 19 en_US
duke.description.startpage 4244 en_US
duke.description.volume 49 en_US
dc.relation.journal Biochemistry en_US
pubs.issue 19
pubs.organisational-group /Duke
pubs.organisational-group /Duke/School of Medicine
pubs.organisational-group /Duke/School of Medicine/Basic Science Departments
pubs.organisational-group /Duke/School of Medicine/Basic Science Departments/Biochemistry
pubs.organisational-group /Duke/School of Medicine/Institutes and Centers
pubs.organisational-group /Duke/School of Medicine/Institutes and Centers/Duke Cancer Institute
pubs.organisational-group /Duke/Trinity College of Arts & Sciences
pubs.organisational-group /Duke/Trinity College of Arts & Sciences/Chemistry
pubs.publication-status Published
pubs.volume 49
dc.identifier.eissn 1520-4995

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