Role of oxidation of excitation-contraction coupling machinery in age-dependent loss of muscle function in C. elegans
- Columbia University Medical Center, United States
- Montpellier University, INSERM, CNRS, France
Abstract
Age-dependent loss of body wall muscle function and impaired locomotion occur within 2 weeks in C. elegans; however, the underlying mechanism has not been fully elucidated. In humans, age-dependent loss of muscle function occurs at about 80 years of age and has been linked to dysfunction of ryanodine receptor (RyR)/intracellular calcium (Ca2+) release channels on the sarcoplasmic reticulum (SR). Mammalian skeletal muscle RyR1 channels undergo age-related remodeling due to oxidative overload, leading to loss of the stabilizing subunit calstabin1 (FKBP12) from the channel macromolecular complex. This destabilizes the closed state of the channel resulting in intracellular Ca2+ leak, reduced muscle function, and impaired exercise capacity. We now show that the C. elegans RyR homolog, UNC-68, exhibits a remarkable degree of evolutionary conservation with mammalian RyR channels and similar age-dependent dysfunction. Like RyR1 in mammals UNC-68 encodes a protein that comprises a macromolecular complex which includes the calstabin1 homolog FKB-2 and is immunoreactive with antibodies raised against the RyR1 complex. Further, as in aged mammals, UNC-68 is oxidized and depleted of FKB-2 in an age-dependent manner, resulting in 'leaky' channels, depleted SR Ca2+ stores, reduced body wall muscle Ca2+ transients, and age-dependent muscle weakness. FKB-2 (ok3007)-deficient worms exhibit reduced exercise capacity. Pharmacologically induced oxidization of UNC-68 and depletion of FKB-2 from the channel independently caused reduced body wall muscle Ca2+ transients. Preventing FKB-2 depletion from the UNC-68 macromolecular complex using the Rycal drug S107 improved muscle Ca2+ transients and function. Taken together, these data suggest that UNC-68 oxidation plays a role in age-dependent loss of muscle function. Remarkably, this age-dependent loss of muscle function induced by oxidative overload, which takes ~2 years in mice and ~80 years in humans, occurs in less than 2-3 weeks in C. elegans, suggesting that reduced antioxidant capacity may contribute to the differences in life span amongst species.
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Funding
National Heart, Lung, and Blood Institute (R01HL145473)
- Andrew Marks
National Institute of Diabetes and Digestive and Kidney Diseases (R01DK118240)
- Andrew Marks
National Heart, Lung, and Blood Institute (R01HL142903)
- Andrew Marks
National Heart, Lung, and Blood Institute (R01HL061503)
- Andrew Marks
National Heart, Lung, and Blood Institute (R01HL140934)
- Andrew Marks
National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR070194)
- Andrew Marks
National Heart, Lung, and Blood Institute (T32HL120826)
- Andrew Marks
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Dridi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Role of oxidation of excitation-contraction coupling machinery in age-dependent loss of muscle function in C. elegans
eLife 11:e75529.
https://doi.org/10.7554/eLife.75529
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