Drp1 Controls Complex II Assembly and Skeletal Muscle Metabolism by Sdhaf2 Action on Mitochondria

Abstract

The Dynamin-related GTPase, Drp1 (encoded by Dnm1l) plays a central role in mitochondrial fission and is requisite for numerous cellular processes however its role in muscle metabolism remains unclear. Herein, we show that among human tissues, the highest number of significant gene correlations with DNM1L are in skeletal muscle. Knockdown of Drp1 (Drp1-KD) promoted mitochondrial hyperfusion in the muscle of male mice. Reduced fatty acid oxidation and impaired insulin action along with increased muscle succinate was observed in Drp1-KD muscle. Muscle Drp1-KD reduced Complex II assembly and activity as a consequence of diminished mitochondrial translocation of succinate dehydrogenase assembly factor 2 (Sdhaf2). Restoration of Sdhaf2 normalized Complex II activity, lipid oxidation, and insulin action in Drp1-KD myocytes. Drp1 is critical in maintaining mitochondrial Complex II assembly, lipid oxidation, and glucose homeostasis, suggesting a mechanistic link between mitochondrial morphology and skeletal muscle metabolism, which is clinically relevant in combatting metabolic diseases. P30DK063491, DK125354. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.