Ca regulation in cardiac myocytes is central to excitation-contraction coupling (ECC) and is also involved in hypertrophic nuclear signaling, mitochondrial energy regulation and cell death. Two important and Ca regulatory systems, Ca-calmodulin (CaM) dependent protein kinase II (CaMKll) and inositol (1,4,5)P3 receptors (InsPsR) are present in myocytes, and have been increasingly implicated in regulating ECC, arrhythmogenesis and nuclear signaling (due in part to studies in this PPG). Indeed, CaMKll is emerging as a nodal point in ECC, arrhythmogenesis and signaling in hypertrophy (Hyp) and heart failure (HF). Overall goals here are to understand better how Ca and CaMKll function in cardiac myocytes with respect to acute Ca signaling (ECC &arrhythmogenesis), mitochondrial function and how both InsPaR and CaMKll may be involved in nuclear signaling (via class II histone deacetylases, HDACs) in hypertrophy &HF. Main experimental methods include confocal fluorescence imaging (of Ca indicators &other fluorescent probes) and voltage clamp in isolated adult cardiac myocytes and hearts (including from transgenic and knockout mice, and HF rabbits). This project has 4 aims.
Aim 1 will measure acute CaMKIIS effects on ECC, and also dynamics of CaM &CaMKll signaling in myocytes, including effects on Ca current facilitation, Na current, SR Ca release (diastolic &systolic) and frequency-dependent acceleration of relaxation.
Aim 2 will test novel hypotheses about Ca/CaM-dependent signaling bv CaMKll &calcineurin to the nucleus via HDAC &NFAT to better understand neurohumoral signaling in Hyo &HF.
Aim 3 will assess how mitochondrial [Cal is regulated in cardiac myocytes, quantitatively and locally, with an eye toward mitochondrial and cell death mechanisms.
Aim 4 will assess altered CaMKll signaling in Hyp &HF regarding ECC, arrhythmias &nuclear signaling. The proposed work will be highly interdigitated with all three other projects in the PPG, taking full advantage of complementary perspectives and expertise of the PPG team. The results will provide comprehensive new information regarding the roles of CaM, CaMKll, calcineurin, mitochondrial Ca and InsPa signaling in cardiac myocytes during ECC, arrhythmogenesis and nuclear signaling in normal ventricular myocytes and during hypertrophy and heart failure.

Public Health Relevance

; Cardiac myocyte calcium signaling is critical to the electrical activity which synchronizes the heartbeat, the contraction that pumps blood, energetic balance at the mitochondrial level, and the control of gene transcription. In heart failure or arrhythmias things go wrong in these pathways, contributing to heart malfunction. Here we will provide novel experimental results in careful quantitative studies, which will help to understand the fundamental workings of these systems critical to health and cardiac disease

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Program Projects (P01)
Project #
5P01HL080101-09
Application #
8697100
Study Section
Heart, Lung, and Blood Initial Review Group (HLBP)
Project Start
Project End
Budget Start
2014-06-01
Budget End
2015-05-31
Support Year
9
Fiscal Year
2014
Total Cost
$477,909
Indirect Cost
$65,580
Name
University of California Davis
Department
Type
DUNS #
047120084
City
Davis
State
CA
Country
United States
Zip Code
95618
Yuen, Garrick K; Galice, Samuel; Bers, Donald M (2017) Subcellular localization of Na/K-ATPase isoforms in ventricular myocytes. J Mol Cell Cardiol 108:158-169
Burel, Sophie; Coyan, Fabien C; Lorenzini, Maxime et al. (2017) C-terminal phosphorylation of NaV1.5 impairs FGF13-dependent regulation of channel inactivation. J Biol Chem 292:17431-17448
Kanaporis, Giedrius; Blatter, Lothar A (2017) Membrane potential determines calcium alternans through modulation of SR Ca2+ load and L-type Ca2+ current. J Mol Cell Cardiol 105:49-58
Bovo, Elisa; Huke, Sabine; Blatter, Lothar A et al. (2017) The effect of PKA-mediated phosphorylation of ryanodine receptor on SR Ca2+ leak in ventricular myocytes. J Mol Cell Cardiol 104:9-16
Bers, Donald M (2017) CALMing Down Arrhythmogenic Calmodulinopathies via a Precision Medicine Approach. Circ Res 120:3-4
Lang, Di; Sato, Daisuke; Jiang, Yanyan et al. (2017) Calcium-Dependent Arrhythmogenic Foci Created by Weakly Coupled Myocytes in the Failing Heart. Circ Res 121:1379-1391
Ma, Xiaolong; Chen, Chao; Veevers, Jennifer et al. (2017) CRISPR/Cas9-mediated gene manipulation to create single-amino-acid-substituted and floxed mice with a cloning-free method. Sci Rep 7:42244
Dewenter, Matthias; Neef, Stefan; Vettel, Christiane et al. (2017) Calcium/Calmodulin-Dependent Protein Kinase II Activity Persists During Chronic ?-Adrenoceptor Blockade in Experimental and Human Heart Failure. Circ Heart Fail 10:e003840
Pereira, Laƫtitia; Bare, Dan J; Galice, Samuel et al. (2017) ?-Adrenergic induced SR Ca2+ leak is mediated by an Epac-NOS pathway. J Mol Cell Cardiol 108:8-16
Blatter, Lothar A (2017) The intricacies of atrial calcium cycling during excitation-contraction coupling. J Gen Physiol 149:857-865

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