Light Up to the Groove, GQR!

21 Apr 2014. NUS scientists have developed a novel BODIPY-based fluorescent sensor (GQR) which can be used as drugs on cancer and HIV treatment.

DNA G-quadruplexes constitute a class of non-canonical nucleic acid structures which is characterized by guanine-rich sequences that folded into polymorphic stacked tetrads. These structures are increasingly recognized as potential therapeutic that targets in anticancer and anti-HIV drug development. In addition, they can be artificially engineered for drug delivery and nanomaterials. G-quadruplexes are structurally diverse (see Figure). And a simple method that can sensitively detect and distinguish the different G-quadruplex topologies remains scarce.

The use of fluorescent probes that “light-up” specifically to the various G-quadruplex structures is one such method. To fulfil this goal, Chang's team has developed a novel BODIPY-based fluorescent sensor (GQR) that can sensitively and specifically probe a specific subset of parallel stranded G-quadruplexes that possess an exposed core end and four medium groves. Such superior selectivity is unprecedented and the effective employment of GQR can in turn accelerate the discovery of new G-quadruplex specific ligands. These discoveries can be used as drugs on cancer and HIV treatment.


Image shows the new G-quadruplex [Image credit: CHANG Young-Tae]


Zhang L, Er JC, Ghosh KK, Chung WJ, Yoo J, Xu W, Zhao W, Phan AT, Chang YT. "Discovery of a structural-element specific G-quadruplex “Light-Up” probe." Scientific Reports 4 (2014) 3776.