Related Experiment Video
Updated: Sep 6, 2025
05:37
Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
835
Biological solution conditions and flanking sequence modulate LLPS of RNA G-quadruplex structures
Allison M Williams1,2, Taylor M Dickson3, Claudia A Lagoa-Miguel4
1Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
RNA (New York, N.Y.)
|June 27, 2022
Summary
Cytosine nucleotides destabilize G-quadruplexes (GQ) in RNA. Additives and flanking sequences influence GQ aggregation and phase separation, impacting their biological roles.
Area of Science:
- Molecular Biology
- Biochemistry
- Structural Biology
Background:
- Guanine-rich sequences form G-quadruplexes (GQ), which can aggregate in vitro.
- Understanding in vivo behavior of GQS is crucial for their biological roles.
Purpose of the Study:
- Investigate the effects of in vivo concentrations of additives on RNA G-quadruplex structure and behavior.
- Determine how flanking sequences and additives influence G-quadruplex aggregation and phase separation.
Main Methods:
- Studied RNA sequences with GQ-forming potential.
- Assessed the impact of amino acids, nucleotides, and crowding agents at biological concentrations.
- Analyzed G-quadruplex structure, aggregation, and phase separation.
Main Results:
- Cytosine nucleotides destabilize model G-quadruplexes at biological salt concentrations.
- Free amino acids and other nucleotides showed minimal destabilization.
- Flanking sequences and additives, especially polyamines, significantly altered G-quadruplex aggregation and phase separation.
- Crowders like PEG and dextran selectively induced phase separation in a biological sequence.
Conclusions:
- Cytosine nucleotides play a role in regulating RNA G-quadruplex stability in vivo.
- G-quadruplex aggregation and phase separation are modulated by flanking sequences and cellular additives.
- Findings suggest G-quadruplexes can participate in liquid-liquid phase separation (LLPS) in vivo.
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