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Updated: May 30, 2026
06:14
Assessment of Mitochondrial Fission/Fusion Dynamics in Kidney Proximal Tubular Cells
Published on: November 14, 2025
mmb1p binds mitochondria to dynamic microtubules.
Chuanhai Fu1, Deeptee Jain, Judite Costa
1Cell & Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA. chuanhai@hku.hk
Current Biology : CB
|August 23, 2011
Summary
A novel protein, mmb1p, facilitates mitochondria distribution in yeast by linking mitochondria to microtubules, independent of motor proteins. This mechanism stabilizes microtubule dynamics, ensuring proper mitochondrial positioning and cell survival.
Area of Science:
- Cell Biology
- Molecular Biology
- Biophysics
Background:
- Mitochondria form dynamic tubular networks crucial for cellular functions.
- Mitochondria positioning in mammalian cells relies on microtubule cytoskeleton and motor proteins.
- A gap exists in understanding how rapid microtubule dynamics (seconds) couple with slower mitochondria distribution (minutes).
Purpose of the Study:
- To investigate novel mechanisms of mitochondria positioning in fission yeast.
- To identify factors coupling microtubule dynamics with mitochondria distribution.
- To elucidate the role of microtubule-mitochondria interactions in cell survival.
Main Methods:
- Genetic screening in fission yeast.
- Protein-protein interaction studies (mitochondria-microtubule binding).
- Microscopy to observe mitochondria and microtubule dynamics.
- Analysis of mmb1p deletion mutants.
Main Results:
- A new microtubule-dependent, motor-independent mechanism for mitochondria positioning was discovered in fission yeast.
- The protein mmb1p was identified as a direct binder of both mitochondria and microtubules.
- mmb1p attachment to microtubules stabilizes them, and its deletion leads to mitochondria aggregation and cell death.
Conclusions:
- mmb1p is a novel protein that binds microtubules and mitochondria.
- mmb1p couples long-term mitochondria distribution to short-term microtubule dynamics.
- By attenuating microtubule dynamics, mmb1p enhances mitochondria-microtubule interaction time, ensuring proper positioning and cell viability.
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