title: Fluorescence light-up probe for parallel G-quadruplexes.
abstract: Putative G-quadruplex-forming sequences (PQS) are highly prevalent in human genome; however, the structures and functions of most PQSs in genome are poorly understood. Therefore, selective recognition of certain types of G-quadruplexes (G4s) is important for the study of G4s. A new light up fluorescent probe, BPBC composed of benzimidazole and carbazole moieties was designed and synthesized. BPBC possesses a crescent-shaped π-conjugated planar core that is slightly larger than the dimension of the G-quartet plane in G4s. This structure endows BPBC with excellent selectivity to parallel G4s. BPBC exhibits almost no fluorescence in the aqueous buffer condition, its fluorescence increases approximately 330-1800-fold in the presence of parallel G4s but only about 30-fold in the presence of single/double-stranded (ss/ds) DNA and 30-110-fold in the presence of antiparallel G4s. Binding studies indicate that the highly selective fluorescent response of BPBC arises from end-stack binding model to G-quartet.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Jin
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Zheng
authors.forename: Xiangjun
authors.initials: X
authors.lastname: Liu
authors.forename: Cui
authors.initials: C
authors.lastname: Qi
authors.forename: Fuyi
authors.initials: F
authors.lastname: Wang
authors.forename: Dihua
authors.initials: D
authors.lastname: Shangguan
mesh_terms: D005456:Fluorescent Dyes / Q000737:chemistry*; D054856:G-Quadruplexes; D006801:Humans; D017433:Protein Structure, Secondary
chemical_list: D005456:Fluorescent Dyes