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Updated: Oct 19, 2025

Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae
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Assessment of Mitochondrial Protein Topology and Membrane Insertion

Kerstin Schäfer1, Carina Engstler1, Korbinian Dischinger1

  • 1Department Biologie I-Botanik, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany.

Methods in Molecular Biology (Clifton, N.J.)
|September 21, 2021
PubMed

Insights

Understanding mitochondrial membrane protein function requires analyzing their structure. This chapter details immunological assays and GFP approaches to determine protein topology and membrane association in mitochondria.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Background:

  • Mitochondrial membrane proteins are crucial for cellular respiration and function.
  • Determining the precise localization and orientation (topology) of these proteins is vital for understanding their roles.
  • Existing methods may not fully elucidate the complex membrane interactions of these proteins.

Purpose of the Study:

  • To present robust methodologies for analyzing mitochondrial membrane protein topology and integrity.
  • To provide a comprehensive guide for researchers studying mitochondrial protein function.
  • To enable accurate determination of protein localization within mitochondrial membranes.

Main Methods:

  • Immunological assays to assess protein solubility and membrane association.
  • Proteolytic cleavage using proteinase K on intact and disrupted mitochondria.
  • In vivo self-assembling Green Fluorescent Protein (GFP) localization approach for plant mitochondrial proteins.

Main Results:

  • Demonstrated how immunological methods can determine the topology of soluble protein domains.
  • Successfully analyzed protein localization using proteinase K digestion across different mitochondrial preparations.
  • Validated the in vivo self-assembling GFP approach for plant mitochondrial protein topology.

Conclusions:

  • Established reliable methods for analyzing mitochondrial membrane protein topology and integrity.
  • These techniques enhance the understanding of mitochondrial protein function.
  • The presented approaches are applicable to diverse research on mitochondrial biology.

Keywords:
Carbonate extractionIn vivo GFP localizationMembrane integrationMembrane protein topologyMembrane solubilizationMitochondrial membrane proteinsMitoplastsOsmotic swellingProteinase K digestionSelf-assembling GFP

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