TY  - JOUR
A1  - Okuda, Takumi
A1  - Lenz, Ann-Kathrin
A1  - Seitz, Florian
A1  - Vogel, Jörg
A1  - Höbartner, Claudia
T1  - A SAM analogue-utilizing ribozyme for site-specific RNA alkylation in living cells
JF  - Nature Chemistry
N2  - Post-transcriptional RNA modification methods are in high demand for site-specific RNA labelling and analysis of RNA functions. In vitro-selected ribozymes are attractive tools for RNA research and have the potential to overcome some of the limitations of chemoenzymatic approaches with repurposed methyltransferases. Here we report an alkyltransferase ribozyme that uses a synthetic, stabilized S-adenosylmethionine (SAM) analogue and catalyses the transfer of a propargyl group to a specific adenosine in the target RNA. Almost quantitative conversion was achieved within 1 h under a wide range of reaction conditions in vitro, including physiological magnesium ion concentrations. A genetically encoded version of the SAM analogue-utilizing ribozyme (SAMURI) was expressed in HEK293T cells, and intracellular propargylation of the target adenosine was confirmed by specific fluorescent labelling. SAMURI is a general tool for the site-specific installation of the smallest tag for azide-alkyne click chemistry, which can be further functionalized with fluorophores, affinity tags or other functional probes.
KW  - Alkyltransferase Ribozyme SAMURI
KW  - Site-specific RNA labelling
KW  - bioorthogonal SAM analogue ProSeDMA
KW  - Chemical modification
KW  - RNA
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-328762
ER  - 
TY  - INPR
A1  - Höbartner, Claudia
A1  - Steinmetzger, Christian
A1  - Palanisamy, Navaneethan
A1  - Gore, Kiran R.
T1  - A multicolor large Stokes shift fluorogen-activating RNA aptamer with cationic chromophores
T2  - Chemistry - A European Journal
N2  - Large Stokes shift (LSS) fluorescent proteins (FPs) exploit excited state proton transfer pathways to enable fluorescence emission from the phenolate intermediate of their internal 4 hydroxybenzylidene imidazolone (HBI) chromophore. An RNA aptamer named Chili mimics LSS FPs by inducing highly Stokes-shifted emission from several new green and red HBI analogs that are non-fluorescent when free in solution. The ligands are bound by the RNA in their protonated phenol form and feature a cationic aromatic side chain for increased RNA affinity and reduced magnesium dependence. In combination with oxidative functional-ization at the C2 position of the imidazolone, this strategy yielded DMHBO\(^+\), which binds to the Chili aptamer with a low-nanomolar K\(_D\). Because of its highly red-shifted fluorescence emission at 592 nm, the Chili–DMHBO\(^+\) complex is an ideal fluorescence donor for Förster resonance energy transfer (FRET) to the rhodamine dye Atto 590 and will therefore find applications in FRET-based analytical RNA systems.
KW  - RNA Aptamer
KW  - fluorescence
KW  - large Stokes shift
KW  - fluorescent protein
KW  - fluorescent resonance energy transfer
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-174197
N1  - This is the pre-peer reviewed version of the following article: Steinmetzger, C. , Palanisamy, N. , Gore, K. . and Höbartner, C. (2018), A multicolor large Stokes shift fluorogen‐activating RNA aptamer with cationic chromophores. Chem. Eur. J. doi:10.1002/chem.201805882, which has been published in final form at https://doi.org/10.1002/chem.201805882. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.
ER  -