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Genetic Code Expansion Facilitates Position-Selective Labeling of RNA for Biophysical Studies.

ABSTRACT: Nature relies on reading and synthesizing the genetic code with high fidelity. Nucleic acid building blocks that are orthogonal to the canonical A-T and G-C base-pairs are therefore uniquely suitable to facilitate position-specific labeling of nucleic acids. Here, we employ the orthogonal kappa-xanthosine-base-pair for in vitro transcription of labeled RNA. We devised an improved synthetic route to obtain the phosphoramidite of the deoxy-version of the kappa nucleoside in solid phase synthesis. From this DNA template, we demonstrate the reliable incorporation of xanthosine during in vitro transcription. Using NMR spectroscopy, we show that xanthosine introduces only minor structural changes in an RNA helix. We furthermore synthesized a clickable 7-deaza-xanthosine, which allows to site-specifically modify transcribed RNA molecules with fluorophores or other labels.

SUBMITTER: Hegelein A

PROVIDER: S-EPMC7027469 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Genetic Code Expansion Facilitates Position-Selective Labeling of RNA for Biophysical Studies.

Hegelein Andreas A Müller Diana D Größl Sylvester S Göbel Michael M Hengesbach Martin M Schwalbe Harald H

Chemistry (Weinheim an der Bergstrasse, Germany) 20200121 8

Nature relies on reading and synthesizing the genetic code with high fidelity. Nucleic acid building blocks that are orthogonal to the canonical A-T and G-C base-pairs are therefore uniquely suitable to facilitate position-specific labeling of nucleic acids. Here, we employ the orthogonal kappa-xanthosine-base-pair for in vitro transcription of labeled RNA. We devised an improved synthetic route to obtain the phosphoramidite of the deoxy-version of the kappa nucleoside in solid phase synthesis. ...[more]

PMID: 31692134

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