1
|
Kampourakis T, Ponnam S, Sun YB, Sevrieva I, Irving M. Structural and functional effects of myosin-binding protein-C phosphorylation in heart muscle are not mimicked by serine-to-aspartate substitutions. J Biol Chem 2018; 293:14270-14275. [PMID: 30082313 PMCID: PMC6139572 DOI: 10.1074/jbc.ac118.004816] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 08/06/2018] [Indexed: 11/15/2022] Open
Abstract
Myosin-binding protein-C (cMyBP-C) is a key regulator of contractility in heart muscle, and its regulatory function is controlled in turn by phosphorylation of multiple serines in its m-domain. The structural and functional effects of m-domain phosphorylation have often been inferred from those of the corresponding serine-to-aspartate (Ser–Asp) substitutions, in both in vivo and in vitro studies. Here, using a combination of in vitro binding assays and in situ structural and functional assays in ventricular trabeculae of rat heart and the expressed C1mC2 region of cMyBP-C, containing the m-domain flanked by domains C1 and C2, we tested whether these substitutions do in fact mimic the effects of phosphorylation. In situ changes in thin and thick filament structure were determined from changes in polarized fluorescence from bifunctional probes attached to troponin C or myosin regulatory light chain, respectively. We show that both the action of exogenous C1mC2 to activate contraction in the absence of calcium and the accompanying change in thin filament structure are abolished by tris-phosphorylation of the m-domain, but unaffected by the corresponding Ser–Asp substitutions. The latter produced an intermediate change in thick filament structure. Both tris-phosphorylation and Ser–Asp substitutions abolished the interaction between C1mC2 and myosin sub-fragment 2 (myosin S2) in vitro, but yielded different effects on thin filament binding. These results suggest that some previous inferences from the effects of Ser–Asp substitutions in cMyBP-C should be reconsidered and that the distinct effects of tris-phosphorylation and Ser–Asp substitutions on cMyBP-C may provide a useful basis for future studies.
Collapse
Affiliation(s)
- Thomas Kampourakis
- From the Randall Centre for Cell and Molecular Biophysics and British Heart Foundation Centre of Research Excellence, School of Basic and Medical Biosciences, King's College London, London SE1 1UL, United Kingdom
| | - Saraswathi Ponnam
- From the Randall Centre for Cell and Molecular Biophysics and British Heart Foundation Centre of Research Excellence, School of Basic and Medical Biosciences, King's College London, London SE1 1UL, United Kingdom
| | - Yin-Biao Sun
- From the Randall Centre for Cell and Molecular Biophysics and British Heart Foundation Centre of Research Excellence, School of Basic and Medical Biosciences, King's College London, London SE1 1UL, United Kingdom
| | - Ivanka Sevrieva
- From the Randall Centre for Cell and Molecular Biophysics and British Heart Foundation Centre of Research Excellence, School of Basic and Medical Biosciences, King's College London, London SE1 1UL, United Kingdom
| | - Malcolm Irving
- From the Randall Centre for Cell and Molecular Biophysics and British Heart Foundation Centre of Research Excellence, School of Basic and Medical Biosciences, King's College London, London SE1 1UL, United Kingdom
| |
Collapse
|
2
|
Tong CW, Wu X, Liu Y, Rosas PC, Sadayappan S, Hudmon A, Muthuchamy M, Powers PA, Valdivia HH, Moss RL. Phosphoregulation of Cardiac Inotropy via Myosin Binding Protein-C During Increased Pacing Frequency or β1-Adrenergic Stimulation. Circ Heart Fail 2015; 8:595-604. [PMID: 25740838 DOI: 10.1161/circheartfailure.114.001585] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 02/24/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND Mammalian hearts exhibit positive inotropic responses to β-adrenergic stimulation as a consequence of protein kinase A-mediated phosphorylation or as a result of increased beat frequency (the Bowditch effect). Several membrane and myofibrillar proteins are phosphorylated under these conditions, but the relative contributions of these to increased contractility are not known. Phosphorylation of cardiac myosin-binding protein-C (cMyBP-C) by protein kinase A accelerates the kinetics of force development in permeabilized heart muscle, but its role in vivo is unknown. Such understanding is important because adrenergic responsiveness of the heart and the Bowditch effect are both depressed in heart failure. METHODS AND RESULTS The roles of cMyBP-C phosphorylation were studied using mice in which either WT or nonphosphorylatable forms of cMyBP-C [ser273ala, ser282ala, ser302ala: cMyBP-C(t3SA)] were expressed at similar levels on a cMyBP-C null background. Force and [Ca(2+)]in measurements in isolated papillary muscles showed that the increased force and twitch kinetics because increased pacing or β1-adrenergic stimulation were nearly absent in cMyBP-C(t3SA) myocardium, even though [Ca(2+)]in transients under each condition were similar to WT. Biochemical measurements confirmed that protein kinase A phosphorylated ser273, ser282, and ser302 in WT cMyBP-C. In contrast, CaMKIIδ, which is activated by increased pacing, phosphorylated ser302 principally, ser282 to a lesser degree, and ser273 not at all. CONCLUSIONS Phosphorylation of cMyBP-C increases the force and kinetics of twitches in living cardiac muscle. Further, cMyBP-C is a principal mediator of increased contractility observed with β-adrenergic stimulation or increased pacing because of protein kinase A and CaMKIIδ phosphorylations of cMyB-C.
Collapse
Affiliation(s)
- Carl W Tong
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Xin Wu
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Yang Liu
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Paola C Rosas
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Sakthivel Sadayappan
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Andy Hudmon
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Mariappan Muthuchamy
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Patricia A Powers
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Héctor H Valdivia
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.)
| | - Richard L Moss
- From the Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison (C.W.T., P.A.P., R.L.M.); Department of Medical Physiology (C.W.T., Y.L., P.C.R., M.M.) and Neuroscience and Experimental Therapeutics (X.W.), Texas A&M University Health Science Center College of Medicine, Temple; Baylor Scott & White Health, Temple, TX (C.W.T.); Department of Physiology, Loyola University Chicago Stritch School of Medicine, IL (S.S.); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis (A.H.); and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor (H.H.V.).
| |
Collapse
|
4
|
Wilson K, Guggilam A, West TA, Zhang X, Trask AJ, Cismowski MJ, de Tombe P, Sadayappan S, Lucchesi PA. Effects of a myofilament calcium sensitizer on left ventricular systolic and diastolic function in rats with volume overload heart failure. Am J Physiol Heart Circ Physiol 2014; 307:H1605-17. [PMID: 25260618 DOI: 10.1152/ajpheart.00423.2014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Aortocaval fistula (ACF)-induced volume overload (VO) heart failure (HF) results in progressive left ventricular (LV) dysfunction. Hemodynamic load reversal during pre-HF (4 wk post-ACF; REV) results in rapid structural but delayed functional recovery. This study investigated myocyte and myofilament function in ACF and REV and tested the hypothesis that a myofilament Ca(2+) sensitizer would improve VO-induced myofilament dysfunction in ACF and REV. Following the initial sham or ACF surgery in male Sprague-Dawley rats (200-240 g) at week 0, REV surgery and experiments were performed at weeks 4 and 8, respectively. In ACF, decreased LV function is accompanied by impaired sarcomeric shortening and force generation and decreased Ca(2+) sensitivity, whereas, in REV, impaired LV function is accompanied by decreased Ca(2+) sensitivity. Intravenous levosimendan (Levo) elicited the best inotropic and lusitropic responses and was selected for chronic oral studies. Subsets of ACF and REV rats were given vehicle (water) or Levo (1 mg/kg) in drinking water from weeks 4-8. Levo improved systolic (% fractional shortening, end-systolic elastance, and preload-recruitable stroke work) and diastolic (τ, dP/dtmin) function in ACF and REV. Levo improved Ca(2+) sensitivity without altering the amplitude and kinetics of the intracellular Ca(2+) transient. In ACF-Levo, increased cMyBP-C Ser-273 and Ser-302 and cardiac troponin I Ser-23/24 phosphorylation correlated with improved diastolic relaxation, whereas, in REV-Levo, increased cMyBP-C Ser-273 phosphorylation and increased α-to-β-myosin heavy chain correlated with improved diastolic relaxation. We concluded that Levo improves LV function, and myofilament composition and regulatory protein phosphorylation likely play a key role in improving function.
Collapse
Affiliation(s)
- Kristin Wilson
- Center for Cardiovascular and Pulmonary Research and The Heart Center, Nationwide Children's Hospital, Columbus, Ohio; Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio
| | - Anuradha Guggilam
- Center for Cardiovascular and Pulmonary Research and The Heart Center, Nationwide Children's Hospital, Columbus, Ohio
| | - T Aaron West
- Center for Cardiovascular and Pulmonary Research and The Heart Center, Nationwide Children's Hospital, Columbus, Ohio
| | - Xiaojin Zhang
- Center for Cardiovascular and Pulmonary Research and The Heart Center, Nationwide Children's Hospital, Columbus, Ohio
| | - Aaron J Trask
- Center for Cardiovascular and Pulmonary Research and The Heart Center, Nationwide Children's Hospital, Columbus, Ohio; Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, Ohio
| | - Mary J Cismowski
- Center for Cardiovascular and Pulmonary Research and The Heart Center, Nationwide Children's Hospital, Columbus, Ohio; Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, Ohio
| | - Pieter de Tombe
- Department of Cellular and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois
| | - Sakthivel Sadayappan
- Department of Cellular and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois
| | - Pamela A Lucchesi
- Center for Cardiovascular and Pulmonary Research and The Heart Center, Nationwide Children's Hospital, Columbus, Ohio; Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, Ohio;
| |
Collapse
|