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Updated: Jun 12, 2026
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Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
5'-UTR G-quadruplex structures acting as translational repressors
Jean-Denis Beaudoin1, Jean-Pierre Perreault
1RNA Group/Groupe ARN, Département de biochimie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, QC, J1H 5N4, Canada.
Nucleic Acids Research
|June 24, 2010
Summary
G-quadruplexes in messenger RNA (mRNA) can act as translational repressors, inhibiting protein production. This study confirms their role in regulating gene expression, particularly within the 5'-untranslated region (5'-UTR).
Area of Science:
- Molecular Biology
- Genetics
- Bioinformatics
Background:
- Over 90% of the human genome is transcribed, necessitating robust post-transcriptional regulation.
- Translational control is a key mechanism for managing mRNA to protein information flow.
Purpose of the Study:
- To investigate the role of G-quadruplexes as translational repressors.
- To evaluate the impact of G-quadruplex formation on protein synthesis.
Main Methods:
- In silico, in vitro, and in cellulo experiments were employed.
- Circular dichroism, thermal denaturation, and in-line probing assessed G-quadruplex folding.
- Reporter gene assays evaluated translational inhibition.
Main Results:
- Six selected sequences formed G-quadruplex structures in vitro.
- All G-quadruplex-forming sequences demonstrated translational inhibition in cellulo.
- Single-nucleotide polymorphisms influenced G-quadruplex formation in the 5 eal-untranslated region (5 eal-UTR).
Conclusions:
- 5 eal-UTR G-quadruplexes function as a widespread class of translational repressors.
- G-quadruplex folding and its regulatory impact are influenced by sequence and genetic variations.
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