Related Experiment Video

Updated: Jun 28, 2025

Analysis of the Expression and Complexes Assembly of the Mitochondrial Respiratory Chain Proteins in the Fission Yeast Schizosaccharomyces pombe
08:07

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

Published on: May 2, 2025

232

The Schizosaccharomyces pombe DEAD-box protein Mss116 is required for mitoribosome assembly and mitochondrial

Yirong Wang1, Gang Feng1, Ying Huang1

  • 1Jiangsu Key Laboratory for Microbes and Functional Genomics, School of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, China.

Mitochondrion
|April 11, 2024
PubMed

Insights

Schizosaccharomyces pombe Mss116 (spMss116) is crucial for mitochondrial gene expression and translation. Its absence impairs mitoribosome assembly, leading to respiratory defects and reduced cell viability.

Area of Science:

  • Mitochondrial biology
  • Molecular genetics
  • Cellular respiration

Background:

  • DEAD-box helicases are essential for mitochondrial gene expression.
  • Mitochondrial respiration relies on proper gene expression and translation.
  • Schizosaccharomyces pombe Mss116 (spMss116) is a key DEAD-box helicase in yeast mitochondria.

Purpose of the Study:

  • To characterize the function of spMss116 in mitochondrial gene expression and translation.
  • To investigate the impact of spMss116 deletion on mitochondrial DNA (mtDNA)-encoded gene products.
  • To determine the role of spMss116 in mitoribosome assembly and function.

Main Methods:

  • Gene deletion studies in Schizosaccharomyces pombe.
  • Analysis of mtDNA-encoded mRNA levels (cox1, cob1).
  • Assessment of mitochondrial translation and respiration.
  • Mitoribosome assembly and protein stability assays.

Main Results:

  • Deletion of spmss116 reduced cox1 and cob1 mRNA levels and impaired mitochondrial translation, causing respiratory defects.
  • Intron removal partially restored mRNA levels but not translation or respiration in Δspmss116 cells.
  • spMss116 deletion impaired mitoribosome assembly and destabilized mitoribosomal proteins in both intron-containing and intronless strains.

Conclusions:

  • spMss116 is essential for maintaining mitochondrial translation and respiration.
  • Defective mitochondrial translation in Δspmss116 cells is primarily caused by impaired mitoribosome assembly.
  • spMss116 plays a critical role in mitoribosome biogenesis and stability.
Keywords:
DEAD-box proteinMitochondrial translationMitoribosome assemblyOXPHOS, Respiration

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