title: Requirement of a macromolecular signaling complex for beta adrenergic receptor modulation of the KCNQ1-KCNE1 potassium channel.
abstract: Sympathetic nervous system (SNS) regulation of cardiac action potential duration (APD) is mediated by beta adrenergic receptor (betaAR) activation, which increases the slow outward potassium ion current (IKS). Mutations in two human I(KS) channel subunits, hKCNQ1 and hKCNE1, prolong APD and cause inherited cardiac arrhythmias known as LQTS (long QT syndrome). We show that betaAR modulation of I(KS) requires targeting of adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase (PKA) and protein phosphatase 1 (PP1) to hKCNQ1 through the targeting protein yotiao. Yotiao binds to hKCNQ1 by a leucine zipper motif, which is disrupted by an LQTS mutation (hKCNQ1-G589D). Identification of the hKCNQ1 macromolecular complex provides a mechanism for SNS modulation of cardiac APD through IKS.
authors.affiliation: Department of Pharmacology, Center for Molecular Cardiology, Department of Medicine, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.
authors.forename: Steven O
authors.initials: SO
authors.lastname: Marx
authors.forename: Junko
authors.initials: J
authors.lastname: Kurokawa
authors.forename: Steven
authors.initials: S
authors.lastname: Reiken
authors.forename: Howard
authors.initials: H
authors.lastname: Motoike
authors.forename: Jeanine
authors.initials: J
authors.lastname: D'Armiento
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Marks
authors.forename: Robert S
authors.initials: RS
authors.lastname: Kass
mesh_terms: D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D054758:A Kinase Anchor Proteins; D000200:Action Potentials; D048868:Adaptor Proteins, Signal Transducing; D019943:Amino Acid Substitution; D000818:Animals; D016466:CHO Cells; D002352:Carrier Proteins / Q000378:metabolism*; D006224:Cricetinae; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D006801:Humans; D051656:KCNQ Potassium Channels; D051657:KCNQ1 Potassium Channel; D016350:Leucine Zippers; D046911:Macromolecular Substances; D051379:Mice; D008822:Mice, Transgenic; D009154:Mutation; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D010766:Phosphorylation; D011188:Potassium / Q000378:metabolism; D015221:Potassium Channels / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D024642:Potassium Channels, Voltage-Gated; D054645:Protein Phosphatase 1; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D054758:A Kinase Anchor Proteins; C119719:AKAP9 protein, human; D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D051656:KCNQ Potassium Channels; D051657:KCNQ1 Potassium Channel; C496909:KCNQ1 protein, human; C496910:Kcnq1 protein, mouse; D046911:Macromolecular Substances; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D011943:Receptors, Adrenergic, beta; D011993:Recombinant Fusion Proteins; C059983:potassium channel protein I(sk); D015124:8-Bromo Cyclic Adenosine Monophosphate; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D011188:Potassium