Titel (eng)

Remodeling of skeletal muscle myosin metabolic states in hibernating mammals

Autor*in

Christopher T. A. Lewis   University of Copenhagen

Julien Ochala   University of Copenhagen

Ryan J. Sprenger   University of British Columbia

Kelly Drew   University of Alaska Fairbanks

Oivind Toien   University of Alaska Fairbanks

Brian Barnes   University of Alaska Fairbanks

Vadim B. Fedorov   University of Alaska Fairbanks

Anna V. Goropashnaya   University of Alaska Fairbanks

James F. Staples   University of Western Ontario

Sylvain Giroud   University of Veterinary Medicine Vienna / Northern Michigan University

Ole Frobert   Aarhus University / Örebro University

Nuria Amigo   Biosfer Teslab

Carla Merino   Biosfer Teslab

Michel N. Kuehn   University of Muenster / Accelerated Muscle Biotechnologies Consultants

Anthony L. Hessel   University of Muenster / Accelerated Muscle Biotechnologies Consultants

Hiroyuki Iwamoto   Japan Synchrotron Radiation Research Institute

Changxin Zhang   University of Michigan

Magnus Gronset   University of Copenhagen

Robert A. E. Seaborne   University of Copenhagen / King's College London

Jenni Laitila   University of Copenhagen

Mathilde S. Olsen   University of Copenhagen

Elise G. Melhedegaard   University of Copenhagen

Marija M. Ognjanovic   University of Copenhagen

Verlag

eLife Sciences Publications Ltd

Beschreibung (eng)

Hibernation is a period of metabolic suppression utilized by many small and large mammal species to survive during winter periods. As the underlying cellular and molecular mechanisms remain incompletely understood, our study aimed to determine whether skeletal muscle myosin and its metabolic efficiency undergo alterations during hibernation to optimize energy utilization. We isolated muscle fibers from small hibernators, Ictidomys tridecemlineatus and Eliomys quercinus and larger hibernators, Ursus arctos and Ursus americanus. We then conducted loaded Mant-ATP chase experiments alongside X-ray diffraction to measure resting myosin dynamics and its ATP demand. In parallel, we performed multiple proteomics analyses. Our results showed a preservation of myosin structure in U. arctos and U. americanus during hibernation, whilst in I. tridecemlineatus and E. quercinus, changes in myosin metabolic states during torpor unexpectedly led to higher levels in energy expenditure of type II, fast-twitch muscle fibers at ambient lab temperatures (20 °C). Upon repeating loaded Mant-ATP chase experiments at 8 °C (near the body temperature of torpid animals), we found that myosin ATP consumption in type II muscle fibers was reduced by 77-107% during torpor compared to active periods. Additionally, we observed Myh2 hyper-phosphorylation during torpor in I. tridecemilineatus, which was predicted to stabilize the myosin molecule. This may act as a potential molecular mechanism mitigating myosin-associated increases in skeletal muscle energy expenditure during periods of torpor in response to cold exposure. Altogether, we demonstrate that resting myosin is altered in hibernating mammals, contributing to significant changes to the ATP consumption of skeletal muscle. Additionally, we observe that it is further altered in response to cold exposure and highlight myosin as a potentially contributor to skeletal muscle non-shivering thermogenesis.

Sprache des Objekts

Englisch

Datum

2024

Rechte

Dieses Werk bzw. dieser Inhalt steht unter einer
CC BY 4.0 - Creative Commons Namensnennung 4.0 International Lizenz.

CC BY 4.0 International

http://creativecommons.org/licenses/by/4.0/

Klassifikation

Animals; Hibernation physiology; Energy Metabolism; Skeletal Muscle Myosinsmetabolism; Ursidaemetabolism physiology; Adenosine Triphosphate metabolism; Muscle, Skeletal metabolism physiology; Muscle Fibers, Skeletal metabolism; Proteomics

Mitglied in der/den Collection(s) (1)