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MBD1 protects replication fork stability by recruiting PARP1 and controlling transcription-replication conflicts
Guihui Yu1, Yundong Xiong1, Zhanzhan Xu1
1Department of Radiation Medicine, School of Basic Medical Sciences, Peking University International Cancer Institute, Beijing Key Laboratory of Tumor Systems Biology, Peking University Health Science Center, Beijing, 100191, China.
Cancer Gene Therapy
|November 10, 2023
Summary
Methyl-CpG Binding Domain 1 (MBD1) is crucial for genomic stability and protecting stalled replication forks in mammalian cells. Loss of MBD1 increases DNA damage and sensitivity to replication stress by affecting transcription-replication conflicts.
Area of Science:
- Cellular biology
- Genetics
- Molecular biology
Background:
- Replication stress response ensures faithful DNA transmission.
- Mechanisms for replication fork stability are not fully understood.
Purpose of the Study:
- Identify novel factors involved in maintaining genomic stability during replication stress.
- Elucidate the role of Methyl-CpG Binding Domain 1 (MBD1) in protecting stalled replication forks.
Main Methods:
- Depletion of MBD1 in mammalian cells.
- Proximity ligation assay combined with 5-ethynyl-2'-deoxyuridine.
- Analysis of DNA lesions, replication fork stability, and R-loop levels.
Main Results:
- MBD1 depletion increases DNA lesions and sensitivity to replication stress.
- Loss of MBD1 causes dissociation of Poly(ADP-ribose) polymerase 1 (PARP1) from replication forks.
- MBD1 depletion leads to increased R-loops and DNA2-mediated degradation of stalled forks.
Conclusions:
- MBD1 is essential for maintaining genome stability by protecting stalled replication forks.
- MBD1 plays a role in resolving transcription-replication conflicts.
- MBD1 influences the recruitment of PARP1 to stalled forks and prevents excessive degradation of replication forks.
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