Hypertrophic cardiomyopathy in cardiac myosin binding protein-C knockout mice.

Published

Journal Article

Familial hypertrophic cardiomyopathy (FHC) is an inherited autosomal dominant disease caused by mutations in sarcomeric proteins. Among these, mutations that affect myosin binding protein-C (MyBP-C), an abundant component of the thick filaments, account for 20% to 30% of all mutations linked to FHC. However, the mechanisms by which MyBP-C mutations cause disease and the function of MyBP-C are not well understood. Therefore, to assess deficits due to elimination of MyBP-C, we used gene targeting to produce a knockout mouse that lacks MyBP-C in the heart. Knockout mice were produced by deletion of exons 3 to 10 from the endogenous cardiac (c) MyBP-C gene in murine embryonic stem (ES) cells and subsequent breeding of chimeric founder mice to obtain mice heterozygous (+/-) and homozygous (-/-) for the knockout allele. Wild-type (+/+), cMyBP-C(+/-), and cMyBP-C(-/-) mice were born in accordance with Mendelian inheritance ratios, survived into adulthood, and were fertile. Western blot analyses confirmed that cMyBP-C was absent in hearts of homozygous knockout mice. Whereas cMyBP-C(+/-) mice were indistinguishable from wild-type littermates, cMyBP-C(-/-) mice exhibited significant cardiac hypertrophy. Cardiac function, assessed using 2-dimensionally guided M-mode echocardiography, showed significantly depressed indices of diastolic and systolic function only in cMyBP-C(-/-) mice. Ca2+ sensitivity of tension, measured in single skinned myocytes, was reduced in cMyBP-C(-/-) but not cMyBP-C(+/-) mice. These results establish that cMyBP-C is not essential for cardiac development but that the absence of cMyBP-C results in profound cardiac hypertrophy and impaired contractile function.

Full Text

Duke Authors

Cited Authors

  • Harris, SP; Bartley, CR; Hacker, TA; McDonald, KS; Douglas, PS; Greaser, ML; Powers, PA; Moss, RL

Published Date

  • March 22, 2002

Published In

Volume / Issue

  • 90 / 5

Start / End Page

  • 594 - 601

PubMed ID

  • 11909824

Pubmed Central ID

  • 11909824

Electronic International Standard Serial Number (EISSN)

  • 1524-4571

Digital Object Identifier (DOI)

  • 10.1161/01.res.0000012222.70819.64

Language

  • eng

Conference Location

  • United States