title: β-adrenergic signaling inhibits Gq-dependent protein kinase D activation by preventing protein kinase D translocation.
abstract: Both β-adrenergic receptor (β-AR) and Gq-coupled receptor (GqR) agonist-driven signaling play key roles in the events, leading up to and during cardiac dysfunction. How these stimuli interact at the level of protein kinase D (PKD), a nodal point in cardiac hypertrophic signaling, remains unclear.
  
  
  
  To assess the spatiotemporal dynamics of PKD activation in response to β-AR signaling alone and on coactivation with GqR-agonists. This will test our hypothesis that compartmentalized PKD signaling reconciles disparate findings of PKA facilitation and inhibition of PKD activation.
  
  
  
  We report on the spatial and temporal profiles of PKD activation using green fluorescent protein-tagged PKD (wildtype or mutant S427E) and targeted fluorescence resonance energy transfer-based biosensors (D-kinase activity reporters) in adult cardiomyocytes. We find that β-AR/PKA signaling drives local nuclear activation of PKD, without preceding sarcolemmal translocation. We also discover pronounced interference of β-AR/cAMP/PKA signaling on GqR-induced translocation and activation of PKD throughout the cardiomyocyte. We attribute these effects to direct, PKA-dependent phosphorylation of PKD-S427. We also show that phosphomimetic substitution of S427 likewise impedes GqR-induced PKD translocation and activation. In neonatal myocytes, S427E inhibits GqR-evoked cell growth and expression of hypertrophic markers. Finally, we show altered S427 phosphorylation in transverse aortic constriction-induced hypertrophy.
  
  
  
  β-AR signaling triggers local nuclear signaling and inhibits GqR-mediated PKD activation by preventing its intracellular translocation. PKA-dependent phosphorylation of PKD-S427 fine-tunes the PKD responsiveness to GqR-agonists, serving as a key integration point for β-adrenergic and Gq-coupled stimuli.
authors.affiliation: From the Department of Pharmacology, University of California, Davis (C.B.N., C.-W.C., M.F., B.M.W., M.L.S., A.J.F., D.H., R.R.R., J.B.); Department of Physiology, Loyola University Chicago, Maywood, IL (C.-W.C.); and School of Engineering, Department of Engineering Design and Production, Aalto University School of Science and Technology, Helsinki, Finland (S.B.).
authors.forename: C Blake
authors.initials: CB
authors.lastname: Nichols
authors.forename: Chia-Wei
authors.initials: CW
authors.lastname: Chang
authors.forename: Maura
authors.initials: M
authors.lastname: Ferrero
authors.forename: Brent M
authors.initials: BM
authors.lastname: Wood
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Stein
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Ferguson
authors.forename: Derrick
authors.initials: D
authors.lastname: Ha
authors.forename: Robert R
authors.initials: RR
authors.lastname: Rigor
authors.forename: Sven
authors.initials: S
authors.lastname: Bossuyt
authors.forename: Julie
authors.initials: J
authors.lastname: Bossuyt
mesh_terms: D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D006332:Cardiomegaly / Q000201:enzymology / Q000473:pathology; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004195:Disease Models, Animal; D004789:Enzyme Activation; D031541:Fluorescence Resonance Energy Transfer; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000378:metabolism*; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology; D010766:Phosphorylation; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D011817:Rabbits; D051381:Rats; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D014162:Transfection
chemical_list: D000318:Adrenergic beta-Agonists; D011943:Receptors, Adrenergic, beta; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D000242:Cyclic AMP; C089212:protein kinase D; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D043802:GTP-Binding Protein alpha Subunits, Gq-G11
keywords: GTP-binding proteins; cyclic AMP-dependent protein kinases; myocytes, cardiac; protein kinase D; receptors, adrenergic