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Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae
08:55

Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae

Published on: July 19, 2021

Tetratricopeptide repeat proteins Tom70 and Tom71 mediate yeast mitochondrial morphogenesis

Noriko Kondo-Okamoto1, Janet M Shaw, Koji Okamoto

  • 1Department of Biochemistry, University of Utah School of Medicine, 15 North Medical Drive East, Salt Lake City, UT 84112-5650, USA. okamoto@nibb.ac.jp

EMBO Reports
|November 17, 2007
PubMed

Insights

Two proteins, Tom70 and Tom71, are essential for the mitochondrial localization of the soluble F-box protein Mfb1 in yeast. Their absence leads to abnormal mitochondrial shapes, highlighting a new role for Tom70 and Tom71 in mitochondrial morphogenesis.

Area of Science:

  • Cell Biology
  • Mitochondrial Biology
  • Protein Trafficking

Background:

  • Mitochondrial shape and connectivity are crucial for cellular function.
  • The soluble F-box protein Mfb1 regulates mitochondrial morphology but its localization mechanism was unknown.
  • Tetratricopeptide repeat proteins Tom70 and Tom71 are involved in protein import and mitochondrial function.

Purpose of the Study:

  • To investigate the mechanism of Mfb1 mitochondrial localization.
  • To determine the role of Tom70 and Tom71 in Mfb1 targeting.
  • To elucidate the function of Tom70 and Tom71 in mitochondrial morphogenesis.

Main Methods:

  • Yeast genetics and mutant analysis.
  • Co-immunoprecipitation assays to study protein interactions.
  • In vitro binding assays to assess protein-mitochondria association.

Main Results:

  • Tom70 and Tom71 are required for Mfb1 mitochondrial localization.
  • Mitochondria lacking Tom70 and Tom71 exhibit aberrant morphologies (short tubules, aggregates).
  • Mfb1 interacts with Tom71 in vivo and binds to mitochondria via Tom70 in vitro.

Conclusions:

  • Tom70 acts as a receptor for soluble proteins like Mfb1 on the mitochondrial surface.
  • Tom71 plays a specialized role in Mfb1-mediated mitochondrial morphogenesis.
  • These findings reveal a novel pathway for mitochondrial protein targeting and shape regulation.

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