title: Stabilization and induction of oligonucleotide i-motif structure via graphene quantum dots.
abstract: DNA i-motif structures have been found in telomeric, centromeric DNA and many in the promoter region of oncogenes; thus they might be attractive targets for gene-regulation processes and anticancer therapeutics. We demonstrate in this work that i-motif structures can be stabilized by graphene quantum dots (GQDs) under acidic conditions, and more importantly GQDs can promote the formation of the i-motif structure under alkaline or physiological conditions. We illustrate that the GQDs stabilize the i-motif structure through end-stacking of the bases at its loop regions, thus reducing its solvent-accessible area. Under physiological or alkaline conditions, the end-stacking of GQDs on the unfolded structure shifts the equilibrium between the i-motif and unfolded structure toward the i-motif structure, thus promoting its formation. The possibility of fine-tuning the stability of the i-motif and inducing its formation would make GQDs useful in gene regulation and oligonucleotide-based therapeutics.
authors.affiliation: Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Zhou
authors.forename: Ting
authors.initials: T
authors.lastname: Han
authors.forename: Jiaying
authors.initials: J
authors.lastname: Wu
authors.forename: Jingyan
authors.initials: J
authors.lastname: Zhang
authors.forename: Shouwu
authors.initials: S
authors.lastname: Guo
mesh_terms: D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure*; D004355:Drug Stability; D006108:Graphite / Q000737:chemistry*; D008422:Materials Testing; D045663:Quantum Dots
chemical_list: D006108:Graphite; D004247:DNA