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Updated: Jun 23, 2026
05:59
Oxygen-Independent Assays to Measure Mitochondrial Function in Mammals
Published on: May 19, 2023
OXPHOS gene expression and control in mitochondrial disorders.
Fimmie Reinecke1, Jan A M Smeitink, Francois H van der Westhuizen
1Centre for Human Metabonomics, School for Physical and Chemical Sciences, North-West University, Hoffman street, Potchefstroom 2531, South Africa.
Biochimica Et Biophysica Acta
|April 25, 2009
Summary
Mitochondrial OXPHOS deficiencies cause metabolic changes, triggering adaptive transcriptional responses in nuclear and mitochondrial genes. Understanding these diverse responses is key to addressing mitochondrial diseases.
Area of Science:
- Biochemistry
- Cell Biology
- Genetics
Background:
- Mitochondrial oxidative phosphorylation (OXPHOS) system deficiencies lead to altered metabolite homeostasis, including reactive oxygen species (ROS), calcium (Ca2+), ADP/ATP, and NAD/NADH levels.
- Adaptive cellular responses involve transcriptional regulation of nuclear and mitochondrial genes, control of the mitochondrial permeability transition pore, and secondary signaling pathways.
Purpose of the Study:
- To review the mechanisms and controlling elements of transcriptional responses in mitochondrial OXPHOS deficiencies.
- To highlight key factors for evaluating OXPHOS gene responses and their impact on mitochondrial disease expression.
Main Methods:
- Literature review of studies on mitochondrial DNA (mtDNA) mutations, deletions, and depletions.
- Analysis of reported transcriptional responses of nuclear and mitochondrial OXPHOS genes.
Main Results:
- Nuclear and mitochondrial OXPHOS genes are predominantly up-regulated in response to mtDNA alterations.
- Expression responses show significant diversity and inconsistency across various disease models.
Conclusions:
- Transcriptional responses to OXPHOS deficiencies are complex and variable.
- Further evaluation of controlling elements is necessary for a comprehensive understanding of mitochondrial disease pathogenesis.
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