Mitochondria Clumping vs. Mitochondria Fusion in CMT2A Diseases
Abstract
:1. Introduction
- (1)
- The source of dysfunction for the MFN2 M376A mutation in the HR1 domain stems from mitofusin in the inactive conformation, notably maintaining its GTPase abilities.
- (2)
- MFN2 M376A lacks perinuclear mitochondrial clumping.
- (3)
- Mitofusin agonists MiM 111 and Chimera C open the MFN2 M376A mutant protein and reverse its dysfunctional mitochondrial fusion abilities.
2. Material and Methods
2.1. Cell Lines
2.2. Viral Vectors
2.3. Protein Structure Modeling
2.4. Imaging
2.5. GTPase Activity Assay
2.6. MFN2 FRET Assays
2.7. Data Presentation and Statistical Analyses
3. Results
3.1. Novel Mechanism of Dysfunction in CMT2A HR1 vs. GTPase Domain Mutation
3.2. MFN2 M376A Induces Short Mitochondria without Depolarization
3.3. Dominant MFN2 M376A Mutation Suppresses Mitochondrial Fusion
3.4. M376A Is a New Shape Shifting Mitofusin 2 Conformational Mutant
4. Discussion
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Franco, A.; Walton, C.E.; Dang, X. Mitochondria Clumping vs. Mitochondria Fusion in CMT2A Diseases. Life 2022, 12, 2110. https://doi.org/10.3390/life12122110
Franco A, Walton CE, Dang X. Mitochondria Clumping vs. Mitochondria Fusion in CMT2A Diseases. Life. 2022; 12(12):2110. https://doi.org/10.3390/life12122110
Chicago/Turabian StyleFranco, Antonietta, Caroline E. Walton, and Xiawei Dang. 2022. "Mitochondria Clumping vs. Mitochondria Fusion in CMT2A Diseases" Life 12, no. 12: 2110. https://doi.org/10.3390/life12122110