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Updated: May 26, 2025
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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
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Calixarenes meet (TG4T)4 G-quadruplex: Exploring reciprocal interactions to develop innovative biotechnological
Andrea Patrizia Falanga1, Maria Cremonini2, Alessio Bartocci3
1Department of Pharmacy, University of Naples Federico II, Via Domenico Montesano 49, 80131 Naples, Italy.
International Journal of Biological Macromolecules
|February 21, 2025
Summary
Calixarene ligands interact with G-quadruplex (GQ) DNA, crucial for gene regulation and telomere maintenance. Ligand structure dictates binding sites, offering potential for therapeutic applications targeting DNA structures.
Area of Science:
- Biochemistry
- Molecular Biology
- Medicinal Chemistry
Background:
- G-quadruplex (GQ) DNA structures are vital in regulating gene expression, telomere maintenance, genome stability, and DNA repair.
- Understanding interactions with GQ DNA is crucial for developing novel therapeutic and biotechnological tools.
Purpose of the Study:
- To investigate the interaction between calixarene ligands and G-quadruplex (GQ) DNA assemblies for the first time.
- To analyze how different functional groups on calixarene ligands affect their binding affinity and specificity towards GQ DNA.
Main Methods:
- Circular dichroism (CD) spectroscopy
- Nuclear Magnetic Resonance (NMR) spectroscopy
- Molecular dynamics (MD) simulations
Main Results:
- Both cationic and zwitterionic calixarene derivatives showed favorable interactions with a model GQ DNA.
- Calixarene ligands induced GQ DNA aggregation at higher concentrations.
- Ligand-GQ interaction specificity varied based on functional groups: proline-rich calixarene favored GQ termini, while guanidinium-functionalized calixarene preferred phosphate groups.
Conclusions:
- Calixarene ligands can recognize and bind to specific structural features of G-quadruplex DNA.
- The functional groups on calixarene upper rims determine their binding selectivity.
- These findings support the development of calixarenes as targeted GQ ligands for therapeutic and biotechnological applications.
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