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Dnm1 Is Required for the Focal Clustering of Fis1 on the Mitochondrial Outer Membrane

Miyu Sasahara1, Shunsuke Matsumoto2, Yasushi Tamura3

  • 1Graduate School of Science and Engineering, Yamagata University.

Micropublication Biology
|September 5, 2025
PubMed

Insights

Mitochondrial protein Fis1

Area of Science:

  • Cell Biology
  • Mitochondrial Dynamics
  • Protein Localization

Background:

  • Mitochondrial fission is crucial for cell function.
  • The Dnm1 GTPase and its receptor Fis1 mediate mitochondrial fission in yeast.
  • Understanding Fis1's spatial distribution is key to elucidating fission regulation.

Purpose of the Study:

  • To investigate the spatial distribution of the mitochondrial receptor Fis1.
  • To determine the relationship between Fis1 localization and Dnm1-mediated mitochondrial fission.

Main Methods:

  • Utilized CRISPR-Cas9 for N-terminal tagging of the FIS1 gene with mNeonGreen.
  • Employed fluorescence microscopy to visualize mNeonGreen-Fis1 localization on mitochondria.
  • Analyzed the impact of Dnm1 on Fis1 clustering.

Main Results:

  • mNeonGreen-Fis1 exhibited both diffuse and punctate localization on mitochondria.
  • Focal clustering of Fis1 was found to be dependent on the Dnm1 GTPase.
  • This suggests Dnm1 influences the spatial organization of its receptor, Fis1.

Conclusions:

  • Dnm1 plays a role in the focal clustering of its receptor Fis1.
  • This highlights a feedback mechanism where a downstream effector impacts upstream receptor distribution.
  • Provides insights into the spatial organization of membrane proteins in mitochondrial dynamics.

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