Cellular Detection of G-Quadruplexes byOptical Imaging Methods

摘要

G-quadruplexes (G4s) are higher-order nucleic acid structures that fold fromguanine (G)-rich DNA and RNA strands. This field of research gains tractionas a major chemical biology area since it aims at uncovering many key cellularmechanisms in which quadruplexes are involved. The wealth of knowledgeacquired over the past three decades strongly supports pivotal roles of G4 inthe regulation of gene expression at both transcriptional (DNA quadruplexes)and translational levels (RNA quadruplexes). Recent biochemical discoveriesuncovered myriad of additional G4 actions: from chromosomal stability to thefiring of replication origins, from telomere homeostasis to functional dysregulationsunderlying genetic diseases (including cancers and neurodegeneration).Here, we listed a repertoire of protocols that we have developed over thepast years to visualize quadruplexes in cells. These achievements were madepossible thanks to the discovery of a novel family of versatile quadruplexselectivefluorophores, the twice-as-smart quadruplex ligands named TASQ(for template-assembled synthetic G-quartet). The versatility of this probe allowsfor multiple imaging techniques in both fixed and live cells, includingthe use of the multiphoton microscopy, confocal microscopy, and real-timefluorescent image collection. C 2017 by John Wiley Sons, Inc.