title: Site-Specific Covalent Labeling of RNA by Enzymatic Transglycosylation.
abstract: We demonstrate the site-specific incorporation of nucleobase derivatives bearing fluorophores or affinity labels into a short RNA stem loop recognition motif by exchange of a guanine residue. The RNA-TAG (transglycosylation at guanosine) is carried out by a bacterial (E. coli) tRNA guanine transglycosylase (TGT), whose natural substrate is the nitrogenous base PreQ1. Remarkably, we have successfully incorporated large functional groups including biotin, BODIPY, thiazole orange, and Cy7 through a polyethylene glycol linker attached to the exocyclic amine of PreQ1. Larger RNAs, such as mRNA transcripts, can be site-specifically labeled if they possess the 17-nucleotide hairpin recognition motif. The RNA-TAG methodology could facilitate the detection and manipulation of RNA molecules by enabling the direct incorporation of functional artificial nucleobases using a simple hairpin recognition element.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States.
authors.forename: Seth C
authors.initials: SC
authors.lastname: Alexander
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States.
authors.forename: Kayla N
authors.initials: KN
authors.lastname: Busby
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States.
authors.forename: Christian M
authors.initials: CM
authors.lastname: Cole
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States.
authors.forename: Cun Yu
authors.initials: CY
authors.lastname: Zhou
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States.
authors.forename: Neal K
authors.initials: NK
authors.lastname: Devaraj
mesh_terms: D004798:Enzymes / Q000737:chemistry*; D006031:Glycosylation; D012313:RNA / Q000737:chemistry*
chemical_list: D004798:Enzymes; D012313:RNA