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Updated: Sep 23, 2026

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
Interaction of porphyrins bearing peripheral cationic heterocycles with G-quadruplex DNA
Y Ishikawa1, T Yamashita, Y Tomisugi
1Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Kumamoto 862-0973, Japan.
Abstract:
Telomere-interactive compounds such as TMPyP4 are expected to inhibit telomerase and thus to be potential anti-cancer drugs. We investigated the interaction of porphyrins bearing peripheral cationic heterocycles with G-quadruplex DNA, which contained human telomeric repeats (GGGTTA)4. One of the porphyrins, pPyTTP, was found to bind to the G-quadruplex DNA and to increase the Tm of the G-quadruplex. The positive sign of induced CD for the complex suggested pPyTTP bound to and stabilized the G-quadruplex DNA possibly by groove binding, distinct from that of TMPyP4.
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