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Updated: Apr 11, 2026
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Visualizing Mitophagy with Fluorescent Dyes for Mitochondria and Lysosome
Published on: November 30, 2022
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Rab12 is a regulator of mitophagy and mitochondrial homeostasis
Tara Richbourg1,2,3, Alex George4, Anas Bitar1,2,3
1Department of Neurology, Duke University School of Medicine, Durham, NC, 27710, USA.
Biorxiv : the Preprint Server for Biology
|April 10, 2026
Summary
Rab12 negatively regulates mitophagy, the process of clearing damaged mitochondria. Its absence enhances mitochondrial clearance and reduces DNA damage, impacting mitochondrial homeostasis and potentially neurodegenerative diseases.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Rab GTPases are key regulators of vesicular trafficking.
- Their specific roles in mitochondrial quality control remain incompletely understood.
- Dysfunctional mitochondria are implicated in various human diseases.
Purpose of the Study:
- To identify novel regulators of mitophagy, a key mitochondrial quality control process.
- To investigate the role of Rab GTPases in mitophagy.
- To determine the specific function of Rab12 in mitochondrial homeostasis.
Main Methods:
- A family-wide siRNA screen was employed using HeLa cells engineered to monitor mitophagy.
- Candidate Rab GTPases were validated through knockdown and knockout experiments.
- Mitochondrial function, DNA damage, and content were assessed after Rab12 manipulation.
Main Results:
- Rab12 was identified as a negative regulator of mitophagy.
- Rab12 depletion enhanced the clearance of damaged mitochondria.
- Loss of Rab12 led to increased mitochondrial content, reduced membrane potential, and decreased mitochondrial DNA damage.
Conclusions:
- Rab12 restrains the initiation of mitophagy.
- Its absence allows for the accumulation of dysfunctional mitochondria that are more susceptible to clearance.
- Rab12 is a novel link between vesicular trafficking and mitochondrial homeostasis, relevant to neurodegenerative disorders.
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