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Structural Principles of Fluorescent RNA Aptamers.

ABSTRACT: Several aptamer RNAs have been selected in vitro that bind to otherwise weakly fluorescent small molecules and enhance their fluorescence several thousand-fold. By genetically tagging cellular RNAs of interest with these aptamers and soaking cells in their cell-permeable cognate small-molecule fluorophores, it is possible to use them to study RNA localization and trafficking. These aptamers have also been fused to metabolite-binding RNAs to generate fluorescent biosensors. The 3D structures of three unrelated fluorogenic RNAs have been determined, and reveal a shared reliance on base quadruples (tetrads) to constrain the photo-excited chromophore. The structural diversity of fluorogenic RNAs and the chemical diversity of potential fluorophores to be activated are likely to yield a variety of future fluorogenic RNA tags that are optimized for different applications in RNA imaging and in the design of fluorescent RNA biosensors.

SUBMITTER: Trachman RJ

PROVIDER: S-EPMC7699827 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Structural Principles of Fluorescent RNA Aptamers.

Trachman Robert J RJ Truong Lynda L Ferré-D'Amaré Adrian R AR

Trends in pharmacological sciences 20170717 10

Several aptamer RNAs have been selected in vitro that bind to otherwise weakly fluorescent small molecules and enhance their fluorescence several thousand-fold. By genetically tagging cellular RNAs of interest with these aptamers and soaking cells in their cell-permeable cognate small-molecule fluorophores, it is possible to use them to study RNA localization and trafficking. These aptamers have also been fused to metabolite-binding RNAs to generate fluorescent biosensors. The 3D structures of t ...[more]

PMID: 28728963

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