Send to

Choose Destination
See comment in PubMed Commons below
Mol Biol Cell. 2003 Aug;14(8):3180-91. Epub 2003 Jun 13.

A novel variant of cardiac myosin-binding protein-C that is unable to assemble into sarcomeres is expressed in the aged mouse atrium.

Author information

Department of Biology, Faculty of Science, Chiba University, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.


Cardiac myosin-binding protein-C (MyBP-C), also known as C-protein, is one of the major myosin-binding proteins localizing at A-bands. MyBP-C has three isoforms encoded by three distinct genes: fast-skeletal, slow-skeletal, and cardiac type. Herein, we are reporting a novel alternative spliced form of cardiac MyBP-C, MyBP-C(+), which includes an extra 30 nucleotides, encoding 10 amino acids in the carboxyl-terminal connectin/titin binding region. This alternative spliced form of MyBP-C(+) has a markedly decreased binding affinity to myosin filaments and connectin/titin in vitro and does not localize to A-bands in cardiac myocytes. When MyBP-C(+) was expressed in chicken cardiac myocytes, sarcomere structure was markedly disorganized, suggesting it has possible dominant negative effects on sarcomere organization. Expression of MyBP-C(+) is hardly detected in ventricles through cardiac development, but its expression gradually increases in atria and becomes the dominant form after 6 mo of age. The present study demonstrates an age-induced new isoform of cardiac MyBP-C harboring possible dominant negative effects on sarcomere assembly.

[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center