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Updated: Jul 11, 2026
08:46
Studying Age-dependent Genomic Instability using the S. cerevisiae Chronological Lifespan Model
Published on: September 29, 2011
What a difference a decade makes: insights into translesion DNA synthesis
1National Institute of Diabetes and Digestive and Kidney Diseases and Laboratory of Genomic Integrity, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA. wei.yang@nih.gov
Summary
Specialized Y-family DNA polymerases perform translesion DNA synthesis (TLS) to bypass DNA damage. While essential for survival, their low fidelity increases mutation risk, potentially leading to cancer.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Cells face constant DNA damage from external agents, threatening genomic integrity.
- Specialized enzymes repair DNA, but persistent lesions can stall DNA replication.
- Translesion DNA synthesis (TLS) is a critical mechanism for bypassing DNA lesions.
Purpose of the Study:
- To review mechanistic insights into TLS by Y-family polymerases.
- To explore the regulation of TLS polymerases.
- To discuss the impact of TLS on genomic instability.
Main Methods:
- Focus on mechanistic studies of Y-family polymerases.
- Analysis of transcriptional and posttranslational regulation of TLS.
- Review of literature on TLS and genomic instability.
Main Results:
- Y-family polymerases possess unique structural features enabling lesion accommodation and bypass.
- These polymerases exhibit low fidelity, increasing mutagenesis.
- Cellular regulation tightly controls TLS polymerase activity and access to replication forks.
Conclusions:
- TLS by Y-family polymerases is crucial for bypassing DNA damage but carries a mutagenic risk.
- Understanding TLS regulation is key to mitigating its detrimental effects on genomic stability.
- Dysregulation of TLS can contribute to human diseases like cancer.
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