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Telomeres and Telomerase

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Related Experiment Video

Updated: Jul 15, 2026

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes

Published on: April 4, 2025

Induction of parallel human telomeric G-quadruplex structures by Sr(2+).

Ilene M Pedroso¹, Luis F Duarte, Giscard Yanez

¹Department of Biochemistry and Molecular Biology, University of Miami, School of Medicine, P.O. Box 016129 (R629), Miami, FL 33101-6129, USA.

Biochemical and Biophysical Research Communications

|May 9, 2007

Summary

Strontium ions (Sr2+) induce human telomeric DNA to form G-quadruplex structures. These parallel-stranded structures, both inter- and intramolecular, offer models for telomerase research and potential anti-cancer drug development.

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Area of Science:

Biochemistry
Structural Biology
Molecular Biology

Background:

Human telomeric DNA forms G-quadruplex structures.
These structures inhibit telomerase and are anti-cancer drug targets.

Purpose of the Study:

Investigate Sr(2+) induction of human telomeric DNA G-quadruplexes.
Characterize the structural properties and cation-specific effects.

Main Methods:

Oligonucleotide synthesis with varying repeats.
Circular dichroism spectroscopy.
Analysis of inter- and intramolecular structures.

Main Results:

Sr(2+) induces both inter- and intramolecular G-quadruplexes.
Sr(2+) favors intermolecular structures with 2-5 repeats.
Parallel-stranded structures observed, distinct from Na(+) or K(+).

Conclusions:

Sr(2+) promotes unique parallel-stranded G-quadruplexes.
These structures serve as models for telomerase substrate recognition.
Potential implications for anti-cancer drug design targeting telomeres.