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Updated: May 11, 2026
05:37
Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
General cell-binding activity of intramolecular G-quadruplexes with parallel structure.
Tianjun Chang1, Cui Qi, Jie Meng
1Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China.
Plos One
|May 3, 2013
Summary
G-quadruplexes (G4s) bind to cellular surface proteins and are internalized via endosomes, independent of binding. These G4 structures show selective anticancer activity, suggesting broad therapeutic potential.
Area of Science:
- Molecular Biology
- Genomics
- Biochemistry
Background:
- G-quadruplexes (G4s) are four-stranded nucleic acid structures formed by guanine-rich sequences.
- Putative G-quadruplex-forming sequences (PQSs) are common in the human genome.
- Some G4s, like AS1411, demonstrate cancer-selective antiproliferative effects and target surface nucleolin.
Purpose of the Study:
- To investigate the general binding and cellular uptake mechanisms of intramolecular G4s with parallel structures.
- To explore the antiproliferative activity of G4s and its relationship with cellular binding.
- To provide insights into G4-cell molecular recognition and potential applications.
Main Methods:
- Testing binding activity of various intramolecular G4s (including PQSs) to multiple cell lines.
- Investigating competitive binding and identifying cellular surface protein targets.
- Analyzing cellular uptake pathways (e.g., endosome/lysosome) and antiproliferative effects.
Main Results:
- Intramolecular G4s, including PQSs, exhibit general binding to diverse cell lines with varying affinities.
- G4 binding interactions are competitive, targeting specific cellular surface proteins.
- Tested G4s show enhanced cellular uptake via the endosome/lysosome pathway, independent of binding, and possess selective antiproliferative activity.
Conclusions:
- G4s possess general binding activity to cells, targeting surface proteins.
- Cellular uptake of G4s occurs through the endosome/lysosome pathway and is independent of direct binding.
- G4s display selective antiproliferative effects, opening avenues for novel cancer therapeutics and diagnostics.
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