TY  - JOUR
A1  - Scheitl, Carolin P. M.
A1  - Okuda, Takumi
A1  - Adelmann, Juliane
A1  - Höbartner, Claudia
T1  - Ribozyme-catalyzed late-stage functionalization and fluorogenic labeling of RNA
JF  - Angewandte Chemie International Edition
N2  - Site-specific introduction of biorthogonal handles into RNAs is in high demand for decorating RNAs with fluorophores, affinity labels or other modifications. Aldehydes represent attractive functional groups for post-synthetic bioconjugation reactions. Here, we report a ribozyme-based method for the synthesis of aldehyde-functionalized RNA by directly converting a purine nucleobase. Using the methyltransferase ribozyme MTR1 as an alkyltransferase, the reaction is initiated by site-specific N1 benzylation of purine, followed by nucleophilic ring opening and spontaneous hydrolysis under mild conditions to yield a 5-amino-4-formylimidazole residue in good yields. The modified nucleotide is accessible to aldehyde-reactive probes, as demonstrated by the conjugation of biotin or fluorescent dyes to short synthetic RNAs and tRNA transcripts. Upon fluorogenic condensation with a 2,3,3-trimethylindole, a novel hemicyanine chromophore was generated directly on the RNA. This work expands the MTR1 ribozyme’s area of application from a methyltransferase to a tool for site-specific late-stage functionalization of RNA.
KW  - Aldehyde Bioconjugation
KW  - Bioorthogonal Tag
KW  - Fluorescence and Crosslinking
KW  - RNA Labelling
KW  - Ribozyme
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-327543
VL  - 62
ER  - 
TY  - INPR
A1  - Seitz, Florian
A1  - Jungnickel, Tina
A1  - Kleiber, Nicole
A1  - Kretschmer, Jens
A1  - Dietzsch, Julia
A1  - Adelmann, Juliane
A1  - Bohnsack, Katherine E.
A1  - Bohnsack, Markus T.
A1  - Höbartner, Claudia
T1  - Atomic mutagenesis of N\(^6\)-methyladenosine reveals distinct recognition modes by human m\(^6\)A reader and eraser proteins
T2  - Journal of the American Chemical Society
N2  - N\(^6\)-methyladenosine (m\(^6\)A) is an important modified nucleoside in cellular RNA associated with multiple cellular processes and is implicated in diseases. The enzymes associated with the dynamic installation and removal of m\(^6\)A are heavily investigated targets for drug research, which requires detailed knowledge of the recognition modes of m\(^6\)A by proteins. Here, we use atomic mutagenesis of m\(^6\)A to systematically investigate the mechanisms of the two human m\(^6\)A demethylase enzymes FTO and ALKBH5 and the binding modes of YTH reader proteins YTHDF2/DC1/DC2. Atomic mutagenesis refers to atom-specific changes that are introduced by chemical synthesis, such as the replacement of nitrogen by carbon atoms. Synthetic RNA oligonucleotides containing site-specifically incorporated 1-deaza-, 3-deaza-, and 7-deaza-m\(^6\)A nucleosides were prepared by solid-phase synthesis and their RNA binding and demethylation by recombinant proteins were evaluated. We found distinct differences in substrate recognition and transformation and revealed structural preferences for the enzymatic activity. The deaza m\(^6\)A analogues introduced in this work will be useful probes for other proteins in m\(^6\)A research.
KW  - modified nucleosides
KW  - N6-methyladenosine (m6A)
KW  - atomic mutagenesis
KW  - YTH reader proteins
KW  - demethylase enzymes FTO and ALKBH5
Y1  - 2024
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-352376
ER  -