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Understanding the Changes in Mitochondrial Morphology through Dynamic and Three-dimensional Fluorescence Micrographs
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Deficits in mitochondrial dynamics and iron balance result in templated insertions
Jordan Fox1, Yang Yu2,3, Yang Yu1
1Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
Nature Communications
|July 2, 2025
Summary
Mitochondrial dysfunction and iron imbalance increase DNA insertions. Yeast mutants lacking mitochondrial fusion or with altered iron homeostasis showed higher levels of genomic insertions, suggesting iron dysregulation causes genome instability.
Area of Science:
- Cell Biology
- Genetics
- Biochemistry
Background:
- Mitochondrial membrane dynamics are crucial for cellular energy production and health.
- Genomic instability, including DNA insertions, can arise from various cellular stresses.
Purpose of the Study:
- To investigate the link between mitochondrial function, iron homeostasis, and genomic insertions in yeast.
- To identify genetic factors contributing to DNA insertion events.
Main Methods:
- Screening of yeast mutants for increased templated DNA insertions.
- Analysis of mitochondrial fusion mutants and iron homeostasis pathways.
- Assessment of DNA damage and iron-sulfur cluster levels.
Main Results:
- Mitochondrial fusion-deficient mutants exhibited increased DNA insertions, activated iron regulon, and decreased iron-sulfur clusters.
- Mutants affecting iron-sulfur cluster production or iron storage also showed high insertion levels.
- Iron chelation and hydrogen peroxide treatment increased DNA insertions, indicating oxidative stress involvement.
Conclusions:
- Iron dysregulation, leading to oxidative DNA damage and impaired DNA repair, drives templated insertions.
- Severe iron imbalance can trigger genome instability, relevant to human diseases and drug treatments.
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