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A Model Membrane Platform for Reconstituting Mitochondrial Membrane Dynamics
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The yeast dynamin-like protein, Mgm1p, functions on the mitochondrial outer membrane to mediate mitochondrial

K A Shepard1, M P Yaffe

  • 1Department of Biology, University of California, San Diego, La Jolla, California 92093-0347, USA.

The Journal of Cell Biology
|February 26, 1999
PubMed

Insights

The mdm17 mutation in yeast disrupts mitochondrial inheritance and morphology. The MGM1 gene, encoding a GTPase, is crucial for these mitochondrial functions.

Area of Science:

  • Cell Biology
  • Genetics
  • Molecular Biology

Background:

  • Mitochondrial inheritance and morphology are vital for cell function.
  • Previous studies suggested MGM1's role in mitochondrial genome maintenance.

Purpose of the Study:

  • To investigate the function of the mdm17 mutation and its associated gene, MGM1.
  • To elucidate the role of Mgm1p in mitochondrial inheritance, morphology, and DNA maintenance.

Main Methods:

  • Yeast genetics: mdm17 mutation analysis, gene cloning, complementation assays.
  • Temperature-shift experiments to observe phenotypic changes.
  • Protein localization and complex analysis.

Main Results:

  • The mdm17 mutation causes temperature-dependent defects in mitochondrial inheritance, morphology, and DNA maintenance.
  • Cloning and expression of the MGM1 gene complemented all mdm17 mutant phenotypes.
  • An mgm1-null mutation and a GTP-binding site mutant of MGM1 resulted in aberrant mitochondrial phenotypes.
  • Mgm1p localizes to the mitochondrial outer membrane and exists in a high molecular weight complex.

Conclusions:

  • Mgm1p is essential for mitochondrial inheritance and morphology in Saccharomyces cerevisiae.
  • Mgm1p functions on the mitochondrial surface as part of a complex.
  • The GTPase activity of Mgm1p is critical for its role in mitochondrial dynamics.

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