Abstract
The i-motif is a biologically relevant non-canonical DNA structure formed by cytosine-rich sequences. Despite the importance of the factors affecting the formation/stability of such a structure, like pH, cation type and concentration, no systematic study that simultaneously analysed their effect on the i-motif in vitro has been carried out so far. Therefore, here we report a systematic study that aims to evaluate the effect of these factors, and their possible interaction, on the formation of an i-motif structure. Our results confirm that pH plays the main role in i-motif formation. However, we demonstrate that the effect of the cation concentration on the i-motif is strictly dependent on the pH, while no significant differences are observed among the investigated cation types.
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Funding
This work was supported by a grant from Regione Campania-POR Campania FESR 2014/2020 (Project No. B61G18000470007) and by the Italian Association for Cancer Research (IG No. 18695 to AR and No. 16730 to BP).
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Iaccarino, N., Di Porzio, A., Amato, J. et al. Assessing the influence of pH and cationic strength on i-motif DNA structure. Anal Bioanal Chem 411, 7473–7479 (2019). https://doi.org/10.1007/s00216-019-02120-6
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DOI: https://doi.org/10.1007/s00216-019-02120-6