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Updated: May 9, 2026
05:37
Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
G-Quadruplex stabilization impairs early embryo development by impairing DNA replication and inducing R-loops and DNA
Ke Xu1,2,3, Chao Li1, Youhui Lu1
1Guangzhou Key Laboratory of Metabolic Diseases and Reproductive Health, Guangdong-Hong Kong Metabolism & Reproduction Joint Laboratory, Reproductive Medicine Center, the Affiliated Guangdong Second Provincial General Hospital of Jinan University, Guangzhou, 510317, China.
Reproduction (Cambridge, England)
|May 7, 2026
Summary
Stabilizing G-quadruplex (G4) DNA structures with ligands disrupts DNA replication and causes double-strand breaks, leading to early embryo arrest. This highlights G4
Area of Science:
- Genetics
- Developmental Biology
- Molecular Biology
Background:
- Precise genomic regulation is vital for early embryonic development.
- G-quadruplex (G4) structures are key genomic elements involved in gene regulation.
- The role of G4 structures in early embryonic development is not well understood.
Purpose of the Study:
- To investigate the effects of G4 ligands on early mouse embryonic development.
- To elucidate the mechanisms by which G4 stabilization impacts embryonic development.
Main Methods:
- Treatment of early mouse embryos with G4 ligands (pyridostatin and Braco-19).
- Analysis of DNA replication, transcription-replication conflicts, R-loop formation, and DNA double-strand breaks.
Main Results:
- Excessive G4 stabilization by ligands disrupted DNA replication.
- Transcription-replication conflicts increased R-loop signals.
- Elevated R-loop signals led to increased double-strand breaks and embryo arrest.
Conclusions:
- G4 structures play a critical role in early embryo cleavage.
- Dysregulation of G4 structures can lead to developmental arrest.
- G4 ligands can induce developmental defects through replication stress and DNA damage.
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