Our long term objective Project 1 is to understand how signals at the level of the cardiac sarcomere serve to coordinate energy supply and energy consumption.
Our aims test the hypothesis that modifications at the level of the sarcomeric proteins serve as significant sites of signal convergence in the progression to heart failure. Our preliminary data indicate a complex coupling, which involves promotion of signaling pathways induced by altered sarcomeric function and that coordinately control energy supply and energy consumption through reciprocol post-translational modifications of sarcomeric proteins. The experiments include investigation of novel findings including: i) differential activation of AMP activated kinase (AMPK) in aerobic conditions in hearts expressing mutant troponin I (cTnl) linked to familial hypertrophic cardiomyopathy (FHC), ii) phosphorylation of cTnl by AMPK;iii) identification of novel cTnl sites of phosphorylation associated with PKCe activation and dilated cardiomyopathy, iii) data predicting metabolically driven sphingolipid signaling to the sarcomeres, and iv) evidence for functionally significant cTnl intra-molecular interactions The specific aims are:
Aim #1. To compare the role of AMPK (AMP activated protein kinase) as a signaling mechanism coordinating energy supply and energy consumption in normal hearts and hearts stressed by expression of sarcomeric proteins inducing increases in Ca-sensitivity and FHC.
Aim #2. To determine the temporal association of the cardiac phenotype of mice expressing PKCe and demonstrating dilated cardiomyopathy with sarcomeric phosphorylation and whether the phenotype is altered by expression of a non-phosphorylatable mutant Tnl lacking the unique N-terminus.
Aim #3. To determine the functional significance of interactions of regions of cTnl with itself and with other thin filament protein sites, potentially significant in coordinating energy demand and supply and modified by AMP kinase (AMPK), protein kinase D (PKD), and PKCe. Approaches to the aims includes studies at the level of the in situ beating heart, isolated myocytes, and skinned fibers with focus on dynamics and evaluation of myofilament Ca-sensitivity and the sarcomere sub-proteome. This project interacts closely with and complements the aims of the other three projects. All three cores strongly support this project. Data generated by the experiments proposed will open a new avenue of research linking metabolic signaling with reciprocal signaling to the sarcomeres, and provide molecular mechanisms of significance in the development of novel diagnostic and therapeutic strategies important in heart failure.

Public Health Relevance

Familial and acquired heart failure are among the most prevalent disorders of the heart and responsible for the majority of hospital admissions in the USA. Studies proposed here offer the potential for novel diagnostic procedures early in the progression of the disorders, and targets for novel therapies.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Program Projects (P01)
Project #
5P01HL062426-13
Application #
8380010
Study Section
Heart, Lung, and Blood Initial Review Group (HLBP)
Project Start
Project End
Budget Start
2012-03-01
Budget End
2013-02-28
Support Year
13
Fiscal Year
2012
Total Cost
$357,262
Indirect Cost
$95,229
Name
University of Illinois at Chicago
Department
Type
DUNS #
098987217
City
Chicago
State
IL
Country
United States
Zip Code
60612
Abraham, Dennis M; Davis 3rd, Robert T; Warren, Chad M et al. (2016) β-Arrestin mediates the Frank-Starling mechanism of cardiac contractility. Proc Natl Acad Sci U S A 113:14426-14431
de Tombe, Pieter P; ter Keurs, Henk E D J (2016) Cardiac muscle mechanics: Sarcomere length matters. J Mol Cell Cardiol 91:148-50
Lin, Ying-Hsi; Warren, Chad M; Li, Jieli et al. (2016) Myofibril growth during cardiac hypertrophy is regulated through dual phosphorylation and acetylation of the actin capping protein CapZ. Cell Signal 28:1015-24
Dvornikov, Alexey V; Smolin, Nikolai; Zhang, Mengjie et al. (2016) Restrictive Cardiomyopathy Troponin I R145W Mutation Does Not Perturb Myofilament Length-dependent Activation in Human Cardiac Sarcomeres. J Biol Chem 291:21817-21828
Li, King-Lun; Ghashghaee, Nazanin Bohlooli; Solaro, R John et al. (2016) Sarcomere length dependent effects on the interaction between cTnC and cTnI in skinned papillary muscle strips. Arch Biochem Biophys 601:69-79
Rosas, Paola C; Liu, Yang; Abdalla, Mohamed I et al. (2015) Phosphorylation of cardiac Myosin-binding protein-C is a critical mediator of diastolic function. Circ Heart Fail 8:582-94
Abrol, Neha; de Tombe, Pieter P; Robia, Seth L (2015) Acute inotropic and lusitropic effects of cardiomyopathic R9C mutation of phospholamban. J Biol Chem 290:7130-40
Davis 3rd, Robert T; Simon, Jillian N; Utter, Megan et al. (2015) Knockout of p21-activated kinase-1 attenuates exercise-induced cardiac remodelling through altered calcineurin signalling. Cardiovasc Res 108:335-47
Utter, Megan S; Ryba, David M; Li, Betty H et al. (2015) Omecamtiv Mecarbil, a Cardiac Myosin Activator, Increases Ca2+ Sensitivity in Myofilaments With a Dilated Cardiomyopathy Mutant Tropomyosin E54K. J Cardiovasc Pharmacol 66:347-53
Warren, Chad M; Karam, Chehade N; Wolska, Beata M et al. (2015) Green Tea Catechin Normalizes the Enhanced Ca2+ Sensitivity of Myofilaments Regulated by a Hypertrophic Cardiomyopathy-Associated Mutation in Human Cardiac Troponin I (K206I). Circ Cardiovasc Genet 8:765-73

Showing the most recent 10 out of 256 publications