Related Experiment Video

Updated: Jun 13, 2025

Analysis of the Expression and Complexes Assembly of the Mitochondrial Respiratory Chain Proteins in the Fission Yeast Schizosaccharomyces pombe
08:08

Analysis of the Expression and Complexes Assembly of the Mitochondrial Respiratory Chain Proteins in the Fission Yeast Schizosaccharomyces pombe

Published on: May 2, 2025

190

Protist biochemistry: Functional SUF system facilitated mitochondrial loss

Maggie Lawton1, Ryan M R Gawryluk1

  • 1Department of Biology, University of Victoria, Victoria, BC V8P 5C2, Canada.

Current Biology : CB
|September 10, 2024
PubMed

Insights

Mitochondria were lost in the anaerobic protist Monocercomonoides exilis due to a functional cytosolic iron-sulfur cluster system replacing the mitochondrial one. This study confirms the system

Area of Science:

  • Cell Biology
  • Evolutionary Biology
  • Biochemistry

Background:

  • Mitochondria are vital organelles in most eukaryotes.
  • Mitochondria possess unique iron-sulfur cluster (ISC) biosynthesis pathways.
  • The anaerobic protist Monocercomonoides exilis lacks mitochondria.

Purpose of the Study:

  • To investigate the mechanism of mitochondrial loss in Monocercomonoides exilis.
  • To confirm the functionality of the cytosolic ISC system in Monocercomonoides exilis.
  • To understand the evolutionary implications of mitochondrial loss.

Main Methods:

  • Bioinformatic analysis of Monocercomonoides exilis genome.
  • Biochemical assays to test ISC protein functionality.
  • Comparative genomics.

Main Results:

  • Monocercomonoides exilis utilizes a cytosolic ISC assembly system.
  • Key ISC proteins show conserved functionality.
  • The cytosolic system appears to fully replace mitochondrial ISC machinery.

Conclusions:

  • The replacement of mitochondrial ISC machinery by a cytosolic system is a plausible cause for mitochondrial loss in Monocercomonoides exilis.
  • This finding provides insights into organelle evolution and adaptation to anaerobic environments.

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