i-motif DNA, short for intercalated-motif DNA, are cytosine-rich four-stranded quadruplex DNA structures, similar to the G-quadruplex structures that are formed in guanine-rich regions of DNA. This structure was first discovered in 1993 by Maurice Guéron at École Polytechnique in Palaiseau, France.

The i-motif represents a paradigmatic example of the wide structural versatility of nucleic acids. In remarkable contrast to duplex DNA, i-motifs are four-stranded DNA structures held together by hemi- protonated and intercalated cytosine base pairs ...

Aug 15, 2014 · i-Motifs are four-stranded DNA secondary structures which can form in sequences rich in cytosine. Stabilised by acidic conditions, they are comprised of two parallel-stranded DNA duplexes held together in an antiparallel orientation by …

Oct 1, 2024 · i-Motifs (iMs, see Glossary), also known as i-DNA, are a type of quadruplex (four-stranded) non-B-DNA structure that folds from cytosine (C)-rich DNA sequences. iM structures consist of antiparallel duplex ladders through intercalation of …

Stretches of cytosine-rich DNA are capable of adopting a dynamic secondary structure, the i-motif. When within promoter regions, the i-motif has the potential to act as a molecular switch for controlling gene expression.

Apr 23, 2018 · Our results support the notion that i-motif structures provide key regulatory roles in the genome. DNA has a well-known propensity to adopt alternative non-B-form conformations in vitro,...

Aug 29, 2024 · i-motifs (iMs) are knot-like DNA structures structures formed in the nuclei of human cells and believed to provide critical genomic regulation. This study uses immunoprecipitation and next-generation sequencing to identify i-motif structures in human DNA on a genome-wide scale. •

Apr 4, 2025 · The i-motif consists of two parallel-stranded duplexes, stabilized by intercalated semi-protonated cytosine–cytosine (C·C +) pairing. Initially, the i-motif was thought to be unstable under physiological pH, which limited its biological interest. However, recent studies have demonstrated the presence of i-motifs in regulatory regions of the ...

Aug 26, 2021 · i-Motifs are four-stranded nucleic acid secondary structures formed from sequences rich in cytosine and are stabilized by hemi-protonated cytosine–cytosine base pairs. In this chapter, we take you through an overview of i-motif nucleic acids: the structure of...

Jul 1, 2022 · Herein, we review the effects of epigenetic modifications on i-motif structure and stability, and biological factors that affect i-motif formation within cells. Furthermore, we highlight recent progress in targeting i-motifs with structure-specific ligands for biotechnology and therapeutic purposes. 1. Introduction.