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RFWD3 and translesion DNA polymerases contribute to PCNA modification-dependent DNA damage tolerance
Rie Kanao1,2, Hidehiko Kawai3, Toshiyasu Taniguchi4
1Department of Genome Dynamics, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan.
Life Science Alliance
|July 29, 2022
Summary
Proliferating cell nuclear antigen (PCNA) modifications are key to DNA damage tolerance. This study reveals Polη-independent pathways involving PCNA K164 modifications, Polκ, and RFWD3 for cellular resistance to DNA damaging agents.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- DNA damage tolerance pathways are crucial for maintaining genomic integrity.
- Proliferating cell nuclear antigen (PCNA) modifications, particularly at lysine 164 (K164), regulate these pathways.
- While translesion DNA synthesis by DNA polymerase η (Polη) is well-characterized, Polη-independent mechanisms remain less understood.
Purpose of the Study:
- To investigate the role of PCNA K164 modifications in cellular resistance to illudin S and its derivatives.
- To identify Polη-independent DNA damage tolerance mechanisms.
- To elucidate the involvement of Polκ and RFWD3 in PCNA modification-dependent DNA damage tolerance.
Main Methods:
- Cellular resistance assays to illudin S and UV irradiation.
- Analysis of PCNA K164 modifications.
- Investigating the roles of Polκ and RFWD3 using genetic approaches.
- Assessing the involvement of the FANC pathway.
Main Results:
- PCNA K164 modification is essential for cellular resistance to illudin S, independent of Polη.
- Polκ and RFWD3 contribute to DNA damage tolerance and depend on PCNA modifications.
- RFWD3 functions in DNA damage tolerance independently of the FANC pathway.
- RFWD3-mediated UV survival is PCNA modification-dependent but Polη-independent.
Conclusions:
- PCNA K164 modifications are critical for tolerance to alkylating agents, involving Polη-independent pathways.
- RFWD3 is a novel component of PCNA modification-dependent DNA damage tolerance, functioning outside the FANC pathway.
- These findings expand our understanding of DNA damage tolerance mechanisms beyond translesion polymerases.
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