TY  - JOUR
A1  - Kleiber, Nicole
A1  - Lemus-Diaz, Nicolas
A1  - Stiller, Carina
A1  - Heinrichs, Marleen
A1  - Mong-Quyen Mai, Mandy
A1  - Hackert, Philipp
A1  - Richter-Dennerlein, Ricarda
A1  - Höbartner, Claudia
A1  - Bohnsack, Katherine E.
A1  - Bohnsack, Markus T.
T1  - The RNA methyltransferase METTL8 installs m\(^3\)C\(_{32}\) in mitochondrial tRNAs\(^{Thr/Ser(UCN)}\) to optimise tRNA structure and mitochondrial translation
JF  - Nature Communication
N2  - Modified nucleotides in tRNAs are important determinants of folding, structure and function. Here we identify METTL8 as a mitochondrial matrix protein and active RNA methyltransferase responsible for installing m\(^3\)C\(_{32}\) in the human mitochondrial (mt-)tRNA\(^{Thr}\) and mt-tRNA\(^{Ser(UCN)}\). METTL8 crosslinks to the anticodon stem loop (ASL) of many mt-tRNAs in cells, raising the question of how methylation target specificity is achieved. Dissection of mttRNA recognition elements revealed U\(_{34}\)G\(_{35}\) and t\(^6\)A\(_{37}\)/(ms\(^2\))i\(^6\)A\(_{37}\), present concomitantly only in the ASLs of the two substrate mt-tRNAs, as key determinants for METTL8-mediated methylation of C\(_{32}\). Several lines of evidence demonstrate the influence of U\(_{34}\), G\(_{35}\), and the m\(^3\)C\(_{32}\) and t\(^6\)A\(_{37}\)/(ms\(^2\))i\(^6\)A\(_{37}\) modifications in mt-tRNA\(^{Thr/Ser(UCN)}\) on the structure of these mt-tRNAs. Although mt-tRNA\(^{Thr/Ser(UCN)}\) lacking METTL8-mediated m\(^3\)C\(_{32}\) are efficiently aminoacylated and associate with mitochondrial ribosomes, mitochondrial translation is mildly impaired by lack of METTL8. Together these results define the cellular targets of METTL8 and shed new light on the role of m\(^3\)C\(_{32}\) within mt-tRNAs.
KW  - Modified Nucleotides in tRNAs
KW  - METTL8
KW  - Mitochondrial Matrix Protein
KW  - RNA Methyltransferase
KW  - RNA
KW  - Enzymes
KW  - Organelles
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-254592
VL  - 13
ER  - 
TY  - INPR
A1  - Sednev, Maksim V.
A1  - Mykhailiuk, Volodymyr
A1  - Choudhury, Priyanka
A1  - Halang, Julia
A1  - Sloan, Katherine E.
A1  - Bohnsack, Markus T.
A1  - Höbartner, Claudia
T1  - N\(^6\)-methyladenosine-sensitive RNA-cleaving deoxyribozymes
T2  - Angewandte Chemie, International Edition
N2  - Deoxyribozymes are synthetic enzymes made of DNA that can catalyze the cleavage or formation of phosphodiester bonds and are useful tools for RNA biochemistry. Here we report new RNA-cleaving deoxyribozymes to interrogate the methylation status of target RNAs, thereby providing an alternative method for the biochemical validation of RNA methylation sites containing N\(^6\)-methyladenosine, which is the most wide-spread and extensively investigated natural RNA modification. Using in vitro selection from random DNA, we developed deoxyribozymes that are sensitive to the presence of N\(^6\)-methyladenosine in RNA near the cleavage site. One class of these DNA enzymes shows faster cleavage of methylated RNA, while others are strongly inhibited by the modified nucleotide. The general applicability of the new deoxyribozymes is demonstrated for several examples of natural RNA sequences, including a lncRNA and a set of C/D box snoRNAs, which have been suggested to contain m\(^6\)A as a regulatory element that influences RNA folding and protein binding.
KW  - N6-methyladenosine
KW  - RNA modification
KW  - deoxyribozymes
KW  - in vitro selection
KW  - DNA catalyst
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171753
N1  - This is the pre-peer reviewed version of the following article: M.V. Sednev, V. Mykhailiuk, P. Choudhury, J. Halang, K. E. Sloan, M. T. Bohnsack, C. Höbartner, Angew. Chem. Int. Ed. 2018, 57, 15117-15121, which has been published in final form at https://doi.org/10.1002/anie.201808745. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.
ER  -