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Rapid Screen of Potential i-Motif Forming Sequences in DNA Repair Gene Promoters.

ABSTRACT: We have studied the in vitro stability of 25 potential i-motif-forming DNA sequences found within the promoter regions of 18 different human DNA repair genes. Three widely available methods of characterization were used to rapidly assess i-motif folding and stability and comprise a simple screen for preliminary identification of physiologically relevant i-motif forming sequences. Four highly pH-stable candidate sequences were identified exhibiting pH transitions (pH at which 50% of the oligodeoxynucleotides in solution are folded) at or above pH 6.6, thermal melting temperatures above 37 °C and isothermal UV difference spectra characteristic of 2'-deoxycytidine imino-nitrogen protonation. These newly identified i-motif forming sequences could represent novel targets for understanding and modulating human DNA repair gene expression.

SUBMITTER: Rogers RA

PROVIDER: S-EPMC6120732 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Rapid Screen of Potential i-Motif Forming Sequences in DNA Repair Gene Promoters.

Rogers R Aaron RA Fleming Aaron M AM Burrows Cynthia J CJ

ACS omega 20180821 8

We have studied the in vitro stability of 25 potential i-motif-forming DNA sequences found within the promoter regions of 18 different human DNA repair genes. Three widely available methods of characterization were used to rapidly assess i-motif folding and stability and comprise a simple screen for preliminary identification of physiologically relevant i-motif forming sequences. Four highly pH-stable candidate sequences were identified exhibiting pH transitions (pH at which 50% of the oligodeox ...[more]

PMID: 30198001

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