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Updated: May 28, 2026
10:47
High-Throughput Image-Based Quantification of Mitochondrial DNA Synthesis and Distribution
Published on: May 5, 2023
The effects of nuclear reprogramming on mitochondrial DNA replication.
Richard D W Kelly1, Huseyin Sumer, Matthew McKenzie
1Centre for Reproduction and Development, Monash Institute of Medical Research, Monash University, 27-31 Wright Street, Clayton, Victoria, 3168, Australia.
Stem Cell Reviews and Reports
|October 14, 2011
Summary
Reprogramming cells to pluripotency disrupts mitochondrial DNA replication. Epigenetic modifiers can restore mitochondrial DNA copy number regulation in induced pluripotent stem cells.
Area of Science:
- Cell Biology
- Mitochondrial Biology
- Epigenetics
Background:
- Embryonic stem cells (ESCs) have low mitochondrial DNA (mtDNA) copy numbers.
- During differentiation, nuclear factors regulate mtDNA replication, notably on Day 6.
- Somatic cells reprogrammed to pluripotency (SC-ES, NT-ES, iPS cells) were investigated for mtDNA replication.
Purpose of the Study:
- To examine mtDNA replication and copy number regulation in reprogrammed somatic cells.
- To compare mtDNA replication dynamics in iPS, SC-ES, and NT-ES cells with ESCs during differentiation.
- To investigate the role of epigenetic modification in restoring mtDNA replication control.
Main Methods:
- Analysis of mtDNA copy number in undifferentiated and differentiating reprogrammed cells.
- Measurement of Nanog and Sox2 expression.
- Assessment of mtDNA replication factors (PolgA, Peo1) expression.
- ATP content measurement.
- Treatment with 5-Azacytidine (DNA methylation inhibitor) prior to differentiation.
Main Results:
- Undifferentiated iPS cells had ESC-like mtDNA levels, while SC-ES and NT-ES cells had higher levels.
- Reprogrammed cells failed to accumulate mtDNA copy number during differentiation, unlike ESCs.
- iPS and SC-ES cells showed impaired ATP regulation compared to differentiating ESCs.
- 5-Azacytidine treatment restored mtDNA copy number accumulation in iPS cells, but not SC-ES or NT-ES cells.
Conclusions:
- Cellular reprogramming disrupts the regulation of mtDNA replication during pluripotency.
- Epigenetic modifiers, like 5-Azacytidine, can re-establish mtDNA copy number control in certain reprogrammed cells (iPS cells).
- These findings highlight the impact of reprogramming on mitochondrial dynamics and suggest epigenetic interventions for restoration.
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