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Mitochondrial sodium-calcium exchange-Can TMEM65 do it alone?
Joanne F Garbincius1, John W Elrod2
1Aging + Cardiovascular Discovery Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA.
Cell Metabolism
|October 8, 2025
Summary
Mitochondrial calcium transport is vital for cell functions. A new study suggests the protein TMEM65 acts as a mitochondrial sodium/calcium exchanger, impacting calcium efflux and cellular processes.
Area of Science:
- Mitochondrial biology
- Cellular signaling
- Ion transport
Background:
- Mitochondrial calcium handling is crucial for cellular signaling, energy production, and programmed cell death.
- Understanding the precise mechanisms of calcium transport across the inner mitochondrial membrane is essential.
Purpose of the Study:
- To investigate the role of the protein TMEM65 in mitochondrial calcium efflux.
- To determine if TMEM65 functions as a mitochondrial sodium/calcium exchanger.
Main Methods:
- The study likely involved biochemical assays and potentially genetic manipulation to assess TMEM65 function.
- Analysis of protein interactions and ion transport activity.
Main Results:
- The protein TMEM65 is proposed to be a key component of the mitochondrial calcium efflux system.
- Evidence suggests TMEM65 operates as a mitochondrial sodium/calcium exchanger.
Conclusions:
- The findings challenge existing models of mitochondrial calcium handling.
- TMEM65 represents a novel target for understanding and potentially modulating mitochondrial calcium dynamics.
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