Homoduplex to i-motif structural switch exhibited by a cytosine rich strand of the MYH7 heavy chain β gene promoter at physiological pH

Designer tryptophan-rich peptide modulates structural dynamics of HIF-1α DNA i-motif DNA

Cytosine-rich DNA sequences can fold into intercalated motifs known as i-motifs, through noncanonical hydrogen bonding interactions. Molecular probes can provide valuable insights into the conformational stability and potential cellular functions of i-motifs. W5K5, a decapeptide composed of alternating tryptophan (W) and lysine (K) units, has been identified as a lead candidate to modulate the structural dynamics of the hypoxia-inducible factor 1-alpha (HIF-1α) DNA i-motif. This finding is expected to facilitate the rational design of peptide-based probes for studying the structure and functional dynamics of i-motifs.

A bimolecular i-motif mediated FRET strategy for imaging protein homodimerization on a living tumor cell surface

A bimolecular i-motif mediated FRET strategy was developed based on the proximity-induced folding of two identical cytosine-rich DNA strands. This strategy affords a FRET signal that is highly matched to the dimerization event, and enabled accurate and dynamic in situ imaging of Met homodimerization on a living tumor cell surface.