Mitochondrial fusion but not fission regulates larval growth and synaptic development through steroid hormone production
- Baylor College of Medicine, United States
- Academia Sinica, Taiwan
- Howard Hughes Medical Institute, Baylor College Of Medicine, United States
- Stanford Hospital and Clinics, United States
- University of Washington, United States
- John Hopkins University, United States
- Howard Hughes Medical Institute, Baylor College of Medicine, United States
Abstract
Mitochondrial fusion and fission affect the distribution and quality control of mitochondria. We show that Marf (Mitochondrial associated regulatory factor), is required for mitochondrial fusion and transport in long axons. Moreover, loss of Marf leads to a severe depletion of mitochondria in neuromuscular junctions (NMJs). Marf mutants also fail to maintain proper synaptic transmission at NMJs upon repetitive stimulation, similar to Drp1 fission mutants. However, unlike Drp1, loss of Marf leads to NMJ morphology defects and extended larval lifespan. Marf is required to form contacts between the endoplasmic reticulum and/or lipid droplets (LDs) and for proper storage of cholesterol and ecdysone synthesis in Ring Glands. Interestingly, human Mitofusin-2 rescues the loss of LD but both Mitofusin-1 and Mitofusin-2 are required for steroid-hormone synthesis. Our data show that Marf and Mitofusins share an evolutionarily conserved role in mitochondrial transport, cholesterol ester storage and steroid-hormone synthesis.
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© 2014, Sandoval 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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Mitochondrial fusion but not fission regulates larval growth and synaptic development through steroid hormone production
eLife 3:e03558.
https://doi.org/10.7554/eLife.03558
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