Back to Search
Start Over
Contribution of the Myosin Binding Protein C Motif to Functional Effects in Permeabilized Rat Trabeculae
- Source :
- The Journal of General Physiology
- Publication Year :
- 2008
- Publisher :
- The Rockefeller University Press, 2008.
-
Abstract
- Myosin binding protein C (MyBP-C) is a thick-filament protein that limits cross-bridge cycling rates and reduces myocyte power output. To investigate mechanisms by which MyBP-C affects contraction, we assessed effects of recombinant N-terminal domains of cardiac MyBP-C (cMyBP-C) on contractile properties of permeabilized rat cardiac trabeculae. Here, we show that N-terminal fragments of cMyBP-C that contained the first three immunoglobulin domains of cMyBP-C (i.e., C0, C1, and C2) plus the unique linker sequence termed the MyBP-C “motif” or “m-domain” increased Ca2+ sensitivity of tension and increased rates of tension redevelopment (i.e., ktr) at submaximal levels of Ca2+. At concentrations ≥20 μM, recombinant proteins also activated force in the absence of Ca2+ and inhibited maximum Ca2+-activated force. Recombinant proteins that lacked the combination of C1 and the motif did not affect contractile properties. These results suggest that the C1 domain plus the motif constitute a functional unit of MyBP-C that can activate the thin filament.
- Subjects :
- Male
Physiology
Amino Acid Motifs
Immunoglobulin domain
030204 cardiovascular system & hematology
Biology
Article
law.invention
03 medical and health sciences
0302 clinical medicine
Myofibrils
law
Catalytic Domain
Myocyte
Animals
Myocytes, Cardiac
Protein Interaction Domains and Motifs
P-Chloroamphetamine
Actin
030304 developmental biology
C1 domain
0303 health sciences
Myosin Subfragments
Articles
Actin cytoskeleton
Myocardial Contraction
Recombinant Proteins
Rats
Actin Cytoskeleton
Biochemistry
Biophysics
Recombinant DNA
Calcium
Myofibril
Carrier Proteins
Subjects
Details
- Language :
- English
- ISSN :
- 15407748 and 00221295
- Volume :
- 132
- Issue :
- 5
- Database :
- OpenAIRE
- Journal :
- The Journal of General Physiology
- Accession number :
- edsair.doi.dedup.....077985dc97b85f0609f59d20216a7e80