| First Author | McConnell BK | Year | 1999 |
| Journal | J Clin Invest | Volume | 104 |
| Issue | 9 | Pages | 1235-44 |
| PubMed ID | 10545522 | Mgi Jnum | J:58295 |
| Mgi Id | MGI:1347180 | Doi | 10.1172/JCI7377 |
| Citation | McConnell BK, et al. (1999) Dilated cardiomyopathy in homozygous myosin-binding protein-C mutant mice [published erratum appears in J Clin Invest 1999 Dec;104(12):1771]. J Clin Invest 104(9):1235-44 |
| abstractText | To elucidate the role of cardiac myosin-binding protein-C (MyBP-C) in myocardial structure and function, we have produced mice expressing altered forms of this sarcomere protein. The engineered mutations encode truncated forms of MyBP-C in which the cardiac myosin heavy chain-binding and titin-binding domain has been replaced with novel amino acid residues. Analogous heterozygous defects in humans cause hypertrophic cardiomyopathy. Mice that are homozygous for the mutated MyBP-C alleles express less than 10% of truncated protein in M-bands of otherwise normal sarcomeres. Homozygous mice bearing mutated MyBP-C alleles are viable but exhibit neonatal onset of a progressive dilated cardiomyopathy with prominent histopathology of myocyte hypertrophy, myofibrillar disarray, fibrosis, and dystrophic calcification. Echocardiography of homozygous mutant mice showed left ventricular dilation and reduced contractile function at birth; myocardial hypertrophy increased as the animals matured. Left-ventricular pressure-volume analyses in adult homozygous mutant mice demonstrated depressed systolic contractility with diastolic dysfunction. These data revise our understanding of the role that MyBP-C plays in myofibrillogenesis during cardiac development and indicate the importance of this protein for long-term sarcomere function and normal cardiac morphology. We also propose that mice bearing homozygous familial hypertrophic cardiomyopathy-causing mutations may provide useful tools for predicting the severity of disease that these mutations will cause in humans. |
