Cargando…

Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle

Myosin-binding protein C (MyBP-C) is a critical regulator of muscle performance that was first identified through its strong binding interactions with myosin, the force-generating protein of muscle. Almost simultaneously with its discovery, MyBP-C was soon found to bind to actin, the physiological c...

Descripción completa

Detalles Bibliográficos
Autor principal: Harris, Samantha P.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Rockefeller University Press 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7721898/
https://www.ncbi.nlm.nih.gov/pubmed/33275758
http://dx.doi.org/10.1085/jgp.202012729
_version_ 1783620107757420544
author Harris, Samantha P.
author_facet Harris, Samantha P.
author_sort Harris, Samantha P.
collection PubMed
description Myosin-binding protein C (MyBP-C) is a critical regulator of muscle performance that was first identified through its strong binding interactions with myosin, the force-generating protein of muscle. Almost simultaneously with its discovery, MyBP-C was soon found to bind to actin, the physiological catalyst for myosin’s activity. However, the two observations posed an apparent paradox, in part because interactions of MyBP-C with myosin were on the thick filament, whereas MyBP-C interactions with actin were on the thin filament. Despite the intervening decades since these initial discoveries, it is only recently that the dual binding modes of MyBP-C are becoming reconciled in models that place MyBP-C at a central position between actin and myosin, where MyBP-C alternately stabilizes a newly discovered super-relaxed state (SRX) of myosin on thick filaments in resting muscle and then prolongs the “on” state of actin on thin filaments in active muscle. Recognition of these dual, alternating functions of MyBP-C reveals how it is central to the regulation of both muscle contraction and relaxation. The purpose of this Viewpoint is to briefly summarize the roles of MyBP-C in binding to myosin and actin and then to highlight a possible new role for MyBP-C in inducing and damping oscillatory waves of contraction and relaxation. Because the contractile waves bear similarity to cycles of contraction and relaxation in insect flight muscles, which evolved for fast, energetically efficient contraction, the ability of MyBP-C to damp so-called spontaneous oscillatory contractions (SPOCs) has broad implications for previously unrecognized regulatory mechanisms in vertebrate striated muscle. While the molecular mechanisms by which MyBP-C can function as a wave maker or a wave breaker are just beginning to be explored, it is likely that MyBP-C dual interactions with both myosin and actin will continue to be important for understanding the new functions of this enigmatic protein.
format Online
Article
Text
id pubmed-7721898
institution National Center for Biotechnology Information
language English
publishDate 2020
publisher Rockefeller University Press
record_format MEDLINE/PubMed
spelling pubmed-77218982021-09-01 Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle Harris, Samantha P. J Gen Physiol Viewpoint Myosin-binding protein C (MyBP-C) is a critical regulator of muscle performance that was first identified through its strong binding interactions with myosin, the force-generating protein of muscle. Almost simultaneously with its discovery, MyBP-C was soon found to bind to actin, the physiological catalyst for myosin’s activity. However, the two observations posed an apparent paradox, in part because interactions of MyBP-C with myosin were on the thick filament, whereas MyBP-C interactions with actin were on the thin filament. Despite the intervening decades since these initial discoveries, it is only recently that the dual binding modes of MyBP-C are becoming reconciled in models that place MyBP-C at a central position between actin and myosin, where MyBP-C alternately stabilizes a newly discovered super-relaxed state (SRX) of myosin on thick filaments in resting muscle and then prolongs the “on” state of actin on thin filaments in active muscle. Recognition of these dual, alternating functions of MyBP-C reveals how it is central to the regulation of both muscle contraction and relaxation. The purpose of this Viewpoint is to briefly summarize the roles of MyBP-C in binding to myosin and actin and then to highlight a possible new role for MyBP-C in inducing and damping oscillatory waves of contraction and relaxation. Because the contractile waves bear similarity to cycles of contraction and relaxation in insect flight muscles, which evolved for fast, energetically efficient contraction, the ability of MyBP-C to damp so-called spontaneous oscillatory contractions (SPOCs) has broad implications for previously unrecognized regulatory mechanisms in vertebrate striated muscle. While the molecular mechanisms by which MyBP-C can function as a wave maker or a wave breaker are just beginning to be explored, it is likely that MyBP-C dual interactions with both myosin and actin will continue to be important for understanding the new functions of this enigmatic protein. Rockefeller University Press 2020-12-04 /pmc/articles/PMC7721898/ /pubmed/33275758 http://dx.doi.org/10.1085/jgp.202012729 Text en © 2020 Harris http://www.rupress.org/terms/https://creativecommons.org/licenses/by-nc-sa/4.0/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/).
spellingShingle Viewpoint
Harris, Samantha P.
Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle
title Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle
title_full Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle
title_fullStr Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle
title_full_unstemmed Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle
title_short Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle
title_sort making waves: a proposed new role for myosin-binding protein c in regulating oscillatory contractions in vertebrate striated muscle
topic Viewpoint
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7721898/
https://www.ncbi.nlm.nih.gov/pubmed/33275758
http://dx.doi.org/10.1085/jgp.202012729
work_keys_str_mv AT harrissamanthap makingwavesaproposednewroleformyosinbindingproteincinregulatingoscillatorycontractionsinvertebratestriatedmuscle