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Redox-dependent control of i-Motif DNA structure using copper cations.

ABSTRACT: Previous computational studies have shown that Cu+ can act as a substitute for H+ to support formation of cytosine (C) dimers with similar conformation to the hemi-protonated base pair found in i-motif DNA. Through a range of biophysical methods, we provide experimental evidence to support the hypothesis that Cu+ can mediate C-C base pairing in i-motif DNA and preserve i-motif structure. These effects can be reversed using a metal chelator, or exposure to ambient oxygen in the air that drives oxidation of Cu+ to Cu2+, a comparatively weak ligand. Herein, we present a dynamic and redox-sensitive system for conformational control of an i-motif forming DNA sequence in response to copper cations.

SUBMITTER: Abdelhamid MA

PROVIDER: S-EPMC6159522 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Redox-dependent control of i-Motif DNA structure using copper cations.

Abdelhamid Mahmoud As MA Fábián László L MacDonald Colin J CJ Cheesman Myles R MR Gates Andrew J AJ Waller Zoë Ae ZA

Nucleic acids research 20180701 12

Previous computational studies have shown that Cu+ can act as a substitute for H+ to support formation of cytosine (C) dimers with similar conformation to the hemi-protonated base pair found in i-motif DNA. Through a range of biophysical methods, we provide experimental evidence to support the hypothesis that Cu+ can mediate C-C base pairing in i-motif DNA and preserve i-motif structure. These effects can be reversed using a metal chelator, or exposure to ambient oxygen in the air that drives ox ...[more]

PMID: 29800233

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