Related Experiment Video
Updated: Jul 25, 2025
05:37
Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
764
Phase Separation Modulates the Formation and Stabilities of DNA Guanine Quadruplex
Zi Gao1, Jun Yuan2, Xiaomei He1
1Department of Chemistry, University of California Riverside, Riverside, California, 92521-0403, United States.
JACS Au
|June 30, 2023
Summary
DNA G-quadruplexes (G4s) can undergo phase separation. Disrupting this process destabilizes G4 structures in human cells, revealing phase separation as a key factor in G4 formation and stability.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- G-rich DNA sequences form G-quadruplex (G4) structures, crucial for genome stability and DNA metabolic processes.
- G4 structures are dynamic and influenced by proteins, but other factors affecting their formation and stability in cells are unclear.
Purpose of the Study:
- To investigate the role of phase separation in the formation and stability of G-quadruplex structures in human cells.
Main Methods:
- In vitro phase separation assays for DNA G4s.
- Immunofluorescence microscopy and ChIP-seq using a G4-specific antibody (BG4).
Main Results:
- DNA G4s were observed to undergo phase separation in vitro.
- Disruption of phase separation led to global destabilization of G4 structures in cells.
Conclusions:
- Phase separation is identified as a novel determinant influencing G-quadruplex formation and stability within human cells.
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