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Updated: Jul 3, 2026
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
The S. Cerevisiae HAP complex, a key regulator of mitochondrial function, coordinates nuclear and mitochondrial gene
S Buschlen1, J-M Amillet, B Guiard
1Laboratoire de Génétique Moléculaire, IGM, Batiment 400. Université Paris Sud, 91405 Orsay Cedex, France.
Comparative and Functional Genomics
|July 17, 2008
Summary
The HAP transcriptional complex globally regulates Saccharomyces cerevisiae gene expression, particularly impacting mitochondrial functions and translation. This complex plays a key role in coordinating nuclear and mitochondrial gene expression for cellular respiration.
Area of Science:
- Molecular Biology
- Yeast Genetics
- Mitochondrial Biology
Background:
- The HAP transcriptional complex is essential for Saccharomyces cerevisiae growth on respiratory substrates.
- Understanding HAP's regulatory role is crucial for elucidating cellular respiration mechanisms.
Purpose of the Study:
- To compare global gene expression in wild-type and HAP mutant Saccharomyces cerevisiae strains.
- To analyze the specific effects of the HAP complex on mitochondrial gene expression and function.
Main Methods:
- Gene expression profiling (comparative genomics) in wild-type and Deltahap2/Deltahap4 mutants of Saccharomyces cerevisiae.
- Bioinformatic analysis of gene regulatory elements (CCAAT-binding sites).
Main Results:
- Hundreds of ORFs are under HAP complex control, with most upregulated genes involved in organelle functions.
- HAP regulates nuclear genes for respiratory chain complexes, mitochondrial translation, import, and division.
- Control of mitochondrial translation by HAP may coordinate nuclear and mitochondrial gene expression.
Conclusions:
- The HAP complex is a high-level regulator of global transcriptional control in Saccharomyces cerevisiae.
- HAP's regulation extends beyond respiratory genes to include mitochondrial dynamics and translation.
- Indirect regulatory mechanisms are suggested by the presence of HAP-regulated genes lacking direct binding sites.
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