The N terminus of myosin-binding protein C extends toward actin filaments in intact cardiac muscle
Authors
Rahmanseresht, SheemaLee, Kyoung H.
O'Leary, Thomas S.
McNamara, James W.
Sadayappan, Sakthivel
Robbins, Jeffrey
Warshaw, David M.
Craig, Roger W.
Previs, Michael J.
Document Type
Journal ArticlePublication Date
2021-02-01Keywords
BiophysicsContraction and Cell Motility
Molecular Physiology
Myofilament
Protein Structure and Dynamics
Amino Acids, Peptides, and Proteins
Biophysics
Cell Biology
Cellular and Molecular Physiology
Molecular Biology
Structural Biology
Metadata
Show full item recordAbstract
Myosin and actin filaments are highly organized within muscle sarcomeres. Myosin-binding protein C (MyBP-C) is a flexible, rod-like protein located within the C-zone of the sarcomere. The C-terminal domain of MyBP-C is tethered to the myosin filament backbone, and the N-terminal domains are postulated to interact with actin and/or the myosin head to modulate filament sliding. To define where the N-terminal domains of MyBP-C are localized in the sarcomere of active and relaxed mouse myocardium, the relative positions of the N terminus of MyBP-C and actin were imaged in fixed muscle samples using super-resolution fluorescence microscopy. The resolution of the imaging was enhanced by particle averaging. The images demonstrate that the position of the N terminus of MyBP-C is biased toward the actin filaments in both active and relaxed muscle preparations. Comparison of the experimental images with images generated in silico, accounting for known binding partner interactions, suggests that the N-terminal domains of MyBP-C may bind to actin and possibly the myosin head but only when the myosin head is in the proximity of an actin filament. These physiologically relevant images help define the molecular mechanism by which the N-terminal domains of MyBP-C may search for, and capture, molecular binding partners to tune cardiac contractility.Source
Rahmanseresht S, Lee KH, O'Leary TS, McNamara JW, Sadayappan S, Robbins J, Warshaw DM, Craig R, Previs MJ. The N terminus of myosin-binding protein C extends toward actin filaments in intact cardiac muscle. J Gen Physiol. 2021 Mar 1;153(3):e202012726. doi: 10.1085/jgp.202012726. PMID: 33528507; PMCID: PMC7852460. Link to article on publisher's site
DOI
10.1085/jgp.202012726Permanent Link to this Item
http://hdl.handle.net/20.500.14038/48484PubMed ID
33528507Related Resources
Rights
© 2021 Rahmanseresht et al. This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms/). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 International license, as described at https://creativecommons.org/licenses/by-nc-sa/4.0/).Distribution License
http://creativecommons.org/licenses/by-nc-sa/4.0/ae974a485f413a2113503eed53cd6c53
10.1085/jgp.202012726
Scopus Count
Except where otherwise noted, this item's license is described as © 2021 Rahmanseresht et al. This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms/). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 International license, as described at https://creativecommons.org/licenses/by-nc-sa/4.0/).