Acceleration of Crossbridge Kinetics by Protein Kinase A Phosphorylation of Cardiac Myosin Binding Protein C Modulates Cardiac Function

被引:153
作者
Tong, Carl W. [1 ]
Stelzer, Julian E. [1 ]
Greaser, Marion L. [1 ]
Powers, Patricia A. [1 ]
Moss, Richard L. [1 ]
机构
[1] Univ Wisconsin, Sch Med & Publ Hlth, Dept Physiol, Madison, WI 53706 USA
关键词
cMyBP-C; phosphorylation; contraction kinetics;
D O I
10.1161/CIRCRESAHA.108.177683
中图分类号
R5 [内科学];
学科分类号
1002 ; 100201 ;
摘要
Normal cardiac function requires dynamic modulation of contraction. beta 1-Adrenergic-induced protein kinase (PK) A phosphorylation of cardiac myosin binding protein (cMyBP)-C may regulate crossbridge kinetics to modulate contraction. We tested this idea with mechanical measurements and echocardiography in a mouse model lacking 3 PKA sites on cMyBP-C, ie, cMyBP-C(t3SA). We developed the model by transgenic expression of mutant cMyBP-C with Ser-to-Ala mutations on the cMyBP-C knockout background. Western blots, immunofluorescence, and in vitro phosphorylation combined to show that non-PKA-phosphorylatable cMyBP-C expressed at 74% compared to normal wild-type (WT) and was correctly positioned in the sarcomeres. Similar expression of WT cMyBP-C at 72% served as control, ie, cMyBP-C(tWT). Skinned myocardium responded to stretch with an immediate increase in force, followed by a transient relaxation of force and finally a delayed development of force, ie, stretch activation. The rate constants of relaxation, k(rel) (s-1), and delayed force development, k(df) (s-1), in the stretch activation response are indicators of crossbridge cycling kinetics. cMyBP-C(t3SA) myocardium had baseline k(rel) and k(df) similar to WT myocardium, but, unlike WT, k(rel) and k(df) were not accelerated by PKA treatment. Reduced dobutamine augmentation of systolic function in cMyBP-C(t3SA) hearts during echocardiography corroborated the stretch activation findings. Furthermore, cMyBP-C(t3SA) hearts exhibited basal echocardiographic findings of systolic dysfunction, diastolic dysfunction, and hypertrophy. Conversely, cMyBP-C(tWT) hearts performed similar to WT. Thus, PKA phosphorylation of cMyBP-C accelerates crossbridge kinetics and loss of this regulation leads to cardiac dysfunction. (Circ Res. 2008; 103:974-982.)
引用
收藏
页码:974 / U166
页数:35
相关论文
共 49 条
[1]   In vivo left ventricular functional capacity is compromised in cMyBP-C null mice [J].
Brickson, S. ;
Fitzsimons, D. P. ;
Pereira, L. ;
Hacker, T. ;
Valdivia, H. ;
Moss, R. L. .
AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY, 2007, 292 (04) :H1747-H1754
[2]   DISTINCT MODULATION OF MYOCARDIAL PERFORMANCE, ENERGY-METABOLISM, AND [CA2+](I) TRANSIENTS BY POSITIVE INOTROPIC DRUGS IN NORMAL AND SEVERELY FAILING HAMSTER HEARTS [J].
BUSER, PT ;
WU, SY ;
PARMLEY, WW ;
JASMIN, G ;
WIKMANCOFFELT, J .
CARDIOVASCULAR DRUGS AND THERAPY, 1995, 9 (01) :151-157
[3]   Blue silver: A very sensitive colloidal Coomassie G-250 staining for proteome analysis [J].
Candiano, G ;
Bruschi, M ;
Musante, L ;
Santucci, L ;
Ghiggeri, GM ;
Carnemolla, B ;
Orecchia, P ;
Zardi, L ;
Righetti, PG .
ELECTROPHORESIS, 2004, 25 (09) :1327-1333
[4]   Length and protein kinase A modulations of myocytes in cardiac myosin binding protein C-deficient mice [J].
Cazorla, O ;
Szilagyi, S ;
Vignier, N ;
Salazar, G ;
Krämer, E ;
Vassort, G ;
Carrier, L ;
Lacampagne, A .
CARDIOVASCULAR RESEARCH, 2006, 69 (02) :370-380
[5]   LOCATION OF C-PROTEIN IN RABBIT SKELETAL-MUSCLE [J].
CRAIG, R ;
OFFER, G .
PROCEEDINGS OF THE ROYAL SOCIETY SERIES B-BIOLOGICAL SCIENCES, 1976, 192 (1109) :451-461
[6]   Myosin-binding protein C phosphorylation, myofibril structure, and contractile function during low-flow ischemia [J].
Decker, RS ;
Decker, ML ;
Kulikovskaya, I ;
Nakamura, S ;
Lee, DC ;
Harris, K ;
Klocke, FJ ;
Winegrad, S .
CIRCULATION, 2005, 111 (07) :906-912
[7]   Molecular determinants of altered Ca2+ handling in human chronic atrial fibrillation [J].
El-Armouche, Ali ;
Boknik, Peter ;
Eschenhagen, Thomas ;
Carrier, Lucie ;
Knaut, Michael ;
Ravens, Ursula ;
Dobrev, Dobromir .
CIRCULATION, 2006, 114 (07) :670-680
[8]   Decreased phosphorylation levels of cardiac myosin-binding protein-C in human and experimental heart failure [J].
El-Armouche, Ali ;
Pohlmann, Lutz ;
Schlossarek, Saskia ;
Starbatty, Jutta ;
Yeh, Yung-Hsin ;
Nattel, Stanley ;
Dobrev, Dobromir ;
Eschenhagen, Thomas ;
Carrier, Lucie .
JOURNAL OF MOLECULAR AND CELLULAR CARDIOLOGY, 2007, 43 (02) :223-229
[9]   Cross-bridge interaction kinetics in rat myocardium are accelerated by strong binding of myosin to the thin filament [J].
Fitzsimons, DP ;
Patel, JR ;
Moss, RL .
JOURNAL OF PHYSIOLOGY-LONDON, 2001, 530 (02) :263-272
[10]   PHOSPHORYLATION SWITCHES SPECIFIC FOR THE CARDIAC ISOFORM OF MYOSIN BINDING PROTEIN-C - A MODULATOR OF CARDIAC CONTRACTION [J].
GAUTEL, M ;
ZUFFARDI, O ;
FREIBURG, A ;
LABEIT, S .
EMBO JOURNAL, 1995, 14 (09) :1952-1960