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Updated: Jul 4, 2025
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Visualization of Endogenous Mitophagy Complexes In Situ in Human Pancreatic Beta Cells Utilizing Proximity Ligation Assay
Published on: May 2, 2019
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PPTC7 limits mitophagy through proximal and dynamic interactions with BNIP3 and NIX
Lianjie Wei1, Mehmet Oguz Gok2, Jordyn D Svoboda1
1Department of Biochemistry & Molecular Biophysics, Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA.
Biorxiv : the Preprint Server for Biology
|February 8, 2024
Summary
Protein phosphatase 7 (PPTC7) regulates mitophagy by promoting the degradation of BNIP3 and NIX proteins. Loss of PPTC7 increases these mitophagy receptors, while its presence on the outer mitochondrial membrane facilitates their turnover.
Area of Science:
- Mitochondrial Biology
- Cellular Homeostasis
- Protein Degradation Pathways
Background:
- Protein phosphatase 7 (PPTC7) is a mitochondrial enzyme crucial for maintaining metabolic homeostasis.
- Previous studies linked PPTC7 knockout to increased mitophagy, but the precise mechanisms were unclear.
- Receptor-mediated mitophagy, involving proteins like BNIP3 and NIX, is essential for mitochondrial quality control.
Conclusions:
- PPTC7 acts as a negative regulator of mitophagy by promoting the degradation of BNIP3 and NIX.
- The catalytic activity of PPTC7 is required, but its mitochondrial matrix localization is not necessary for this function.
- Dynamic recruitment of PPTC7 to the outer mitochondrial membrane is a key mechanism for controlling mitophagy receptor turnover.
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