Cover Image, Volume 107, Issue 7

Many of the important genomic regions consist of sequences with the potential to form i‐motifs: four‐stranded DNA secondary structures. Sarika Saxena et al. investigate the effect of Mg2+ and Ca2+ on the structure of three C‐rich oligonucleotides in physiological ionic conditions and cell‐mimicking molecular crowding conditions. The sequences form an i‐motif at acidic pH in the presence of Ca2+ and Mg2+, as well as at neutral pH in the presence of Mg2+. Cell‐mimicking molecular crowding promoted i‐motif formation for all three oligonucleotides. The work suggests that intracellular conditions where hydration becomes less favourable may facilitate the folding of C‐rich sequences into i‐motifs. (DOI: 10.1002/bip.23018)

Source: Biopolymers - April 22, 2017 Category: Biochemistry Tags: COVER IMAGE Source Type: research