OBJECTIVE: Titin isoform expression patterns were examined to explain previously observed genetic differences in rat cardiac passive tension. METHODS: Rat ventricles from male spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats (normotensive) were used to analyze the titin isoform patterns. The hypertensive status was verified by blood pressure measurements and heart weight to body weight ratios. Gel electrophoresis and scanning densitometry were performed to determine ratios of myosin heavy chain and titin isoforms expressed. In situ hybridization using a cRNA probe specific for N2BA titin and a positive control in the N2B unique region was used to demonstrate tissue location of the titin message. RESULTS: Regression analysis of titin isoform ratios, myosin heavy chain isoform ratios, and heart weight to body weight ratios all suggest a smaller proportion of N2BA titin (longer isoform) was expressed in rat left ventricles with increased hypertrophy. In situ hybridization showed that the N2BA and N2B isoforms were co-expressed within most of the cardiomyocytes. Agarose gel electrophoresis demonstrated two different N2BA titin isoforms in all rat ventricles. CONCLUSIONS: Expression of less N2BA and more N2B titin in response to pressure overload will result in higher passive tension upon stretch at a given sarcomere length and thus affect cardiac performance.
OBJECTIVE:Titin isoform expression patterns were examined to explain previously observed genetic differences in rat cardiac passive tension. METHODS:Rat ventricles from male spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats (normotensive) were used to analyze the titin isoform patterns. The hypertensive status was verified by blood pressure measurements and heart weight to body weight ratios. Gel electrophoresis and scanning densitometry were performed to determine ratios of myosin heavy chain and titin isoforms expressed. In situ hybridization using a cRNA probe specific for N2BA titin and a positive control in the N2B unique region was used to demonstrate tissue location of the titin message. RESULTS: Regression analysis of titin isoform ratios, myosin heavy chain isoform ratios, and heart weight to body weight ratios all suggest a smaller proportion of N2BA titin (longer isoform) was expressed in rat left ventricles with increased hypertrophy. In situ hybridization showed that the N2BA and N2B isoforms were co-expressed within most of the cardiomyocytes. Agarose gel electrophoresis demonstrated two different N2BA titin isoforms in all rat ventricles. CONCLUSIONS: Expression of less N2BA and more N2B titin in response to pressure overload will result in higher passive tension upon stretch at a given sarcomere length and thus affect cardiac performance.
Authors: Anna Raskin; Stephan Lange; Katherine Banares; Robert C Lyon; Anke Zieseniss; Leonard K Lee; Katrina G Yamazaki; Henk L Granzier; Carol C Gregorio; Andrew D McCulloch; Jeffrey H Omens; Farah Sheikh Journal: J Biol Chem Date: 2012-07-09 Impact factor: 5.157
Authors: Leta S Steffen; Jeffrey R Guyon; Emily D Vogel; Melanie H Howell; Yi Zhou; Gerhard J Weber; Leonard I Zon; Louis M Kunkel Journal: Dev Biol Date: 2007-06-23 Impact factor: 3.582
Authors: Betty Pat; Yuanwen Chen; Cheryl Killingsworth; James D Gladden; Ke Shi; Junying Zheng; Pamela C Powell; Greg Walcott; Mustafa I Ahmed; Himanshu Gupta; Ravi Desai; Chih-Chang Wei; Naoki Hase; Tsunefumi Kobayashi; Abdelkarim Sabri; Henk Granzier; Thomas Denney; Michael Tillson; A Ray Dillon; Ahsan Husain; Louis J Dell'italia Journal: Circulation Date: 2010-09-27 Impact factor: 29.690
Authors: I M Vikhlyantseva; Z A Podlubnaya; E V Karaduleva; R N Khramov; A N Murashev; I B Kozlovskaya Journal: Dokl Biochem Biophys Date: 2007 Nov-Dec Impact factor: 0.788
Authors: Carlos G Hidalgo; Charles S Chung; Chandra Saripalli; Mei Methawasin; Kirk R Hutchinson; George Tsaprailis; Siegfried Labeit; Alicia Mattiazzi; Henk L Granzier Journal: J Mol Cell Cardiol Date: 2012-12-05 Impact factor: 5.000
Authors: Marion L Greaser; Chad M Warren; Karla Esbona; Wei Guo; Yingli Duan; Amanda M Parrish; Paul R Krzesinski; Holly S Norman; Sandra Dunning; Daniel P Fitzsimons; Richard L Moss Journal: J Mol Cell Cardiol Date: 2008-02-23 Impact factor: 5.000