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Length dependence of striated muscle force generation is controlled by phosphorylation of cTnI at serines 23/24

, : Length dependence of striated muscle force generation is controlled by phosphorylation of cTnI at serines 23/24. Journal of Physiology 591(18): 4535-4547

According to the Frank-Starling relationship, greater end diastolic volume increases ventricular output. The Frank-Starling relationship is based, in part, on the length-tension relationship in cardiac myocytes. Recently, we identified a dichotomy in the steepness of length-tension relationships in mammalian cardiac myocytes that was dependent upon PKA-induced myofibrillar phosphorylation. Since PKA has multiple myofibrillar substrates including titin, myosin binding protein-C (MyBP-C), and cardiac troponin I (cTnI), we sought to define if phosphorylation of one of these molecules could control length-tension relationships. We focused on cTnI since troponin can be exchanged in permeabilized striated muscle cell preparations and tested the hypothesis that phosphorylation of cTnI modulates length dependence of force generation. For these experiments, we exchanged unphosphorylated recombinant cardiac troponin (cTn) into either a rat cardiac myocyte preparation or a skinned slow-twitch skeletal muscle fibre. In all cases unphosphorylated cTn yielded a shallow length-tension relationship, which was shifted to a steep relationship after PKA treatment. Furthermore, exchange with cTn having cTnI serines 23 and 24 mutated to aspartic acids to mimic phosphorylation always shifted a shallow length-tension relationship to a steep relationship. Overall, these results indicate that phosphorylation of cTnI serines 23/24 is a key regulator of length dependence of force generation in striated muscle.This article is protected by copyright. All rights reserved.

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Accession: 036967585

PMID: 23836688

DOI: 10.1113/jphysiol.2013.258400

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di Bari, Donato., 1995: Foraminiferi glomospirali della Formazione di S. Cassiano (Carnico, Dolomiti). Palaeopelagos. 1994( ); 4: 267-274

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Ernst R.A.; Ogasawara F.X.; Fuqua L., 1969: Effect of 3 semen extenders on reproduction of turkeys. Poultry Science 48(5): 1805

Neubauer, J., 1973: Increasing the protein yield of permanent pasture by nitrogen fertilization. The effects of increasing N on crude protein content, dry matter yield and digestible protein yield of pasture at five sites (altitudes 309-530 m) are tabulated. N fertilizer effects showed significant interactions with site, management and year.

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Huang, Yi; Fang, Yong; Dziadyk, Jennifer, M.; Norris, James, S.; Fan, Weimin, 2002: The possible correlation between activation of NF-kappaB/IkappaB pathway and the susceptibility of tumor cells to paclitaxel-induced apoptosis. Paclitaxel (Taxol(R)) is a naturally occurring antimitotic agent that has been shown to induce apoptosis in both leukemic and solid tumor cells, but many tumor cells exhibit a high resistance to paclitaxel. The mechanism of different susceptibilit...

Gray, J. E.; Lewis, C., 1966: Enigma of antibiotic-induced diarrhea in the laboratory rabbit. Lincomycin hydrochloride caused diarrhoea and death of rabbits when given in an amount as small as one-hundredth of that tolerated by rats and dogs. Penicillin and erythromycin also had this effect on rabbits. The caecal flora changed from predomi...

Abou Ziena, H. A. A.; Rakha, G. M.; Berbish, E. A., 2002: Congenital goitre and mineral imbalance in goat kids. This study was conducted to investigate the changes in the function of the thyroid and the mineral status which occurred during hypothyroidism and post-thyroidectomy in 14 goat kids suffering from congenital goitre. Results of the tests of the kid...

Eaton, E. L., Et Al., 1943: The blueberry. A well illustrated bulletin on all aspects of blueberry culture in Canada in four sections. (I) EATON, E. L. Blueberry culture, pp. 5-16. The position is reviewed by provinces and the growing both of low-bush and high-bush blueberry is described.

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