title: Indole-based cyanine as a nuclear RNA-selective two-photon fluorescent probe for live cell imaging.
abstract: We have demonstrated that the subcellular targeting properties of the indole-based cyanines can be tuned by the functional substituent attached onto the indole moiety in which the first example of a highly RNA-selective and two-photon active fluorescent light-up probe for high contrast and brightness TPEF images of rRNA in the nucleolus of live cells has been developed. It is important to find that this cyanine binds much stronger toward RNA than DNA in a buffer solution as well as selectively stains and targets to rRNA in the nucleolus. Remarkably, the TPEF brightness (Φσmax) is dramatically increased with 11-fold enhancement in the presence of rRNA, leading to the record high Φσmax of 228 GM for RNA. This probe not only shows good biocompatibility and superior photostability but also offers general applicability to various live cell lines including HeLa, HepG2, MCF-7, and KB cells and excellent counterstaining compatibility with commercially available DNA or protein trackers.
authors.affiliation: †Department of Chemistry and Institute of Molecular Functional Materials, Hong Kong Baptist University, 224 Waterloo Road, Hong Kong SAR, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Guo
authors.affiliation: §Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China.
authors.forename: Miu Shan
authors.initials: MS
authors.lastname: Chan
authors.affiliation: †Department of Chemistry and Institute of Molecular Functional Materials, Hong Kong Baptist University, 224 Waterloo Road, Hong Kong SAR, China.
authors.forename: Di
authors.initials: D
authors.lastname: Xu
authors.affiliation: §Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China.
authors.forename: Dick Yan
authors.initials: DY
authors.lastname: Tam
authors.affiliation: ⊥Laboratoire de Conception et Application des Molécules Bioactives, UMR University of Strasbourg-CNRS 7199, Faculté de Pharmacie, Université de Strasbourg, Strasbourg, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Bolze
authors.affiliation: §Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China.
authors.forename: Pik Kwan
authors.initials: PK
authors.lastname: Lo
authors.forename: Man Shing
authors.initials: MS
authors.lastname: Wong
mesh_terms: D005456:Fluorescent Dyes / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D007211:Indoles / Q000737:chemistry*; D015138:RNA, Nuclear / Q000032:analysis*
chemical_list: D005456:Fluorescent Dyes; D007211:Indoles; D015138:RNA, Nuclear