Details

Autor(en) / Beteiligte

• Fürtig, Boris
• Schnieders, Robbin
• Richter, Christian
• Zetzsche, Heidi
• Keyhani, Sara
• Helmling, Christina
• Kovacs, Helena
• Schwalbe, Harald

Titel

Direct 13C-detected NMR experiments for mapping and characterization of hydrogen bonds in RNA

Ist Teil von

• Journal of biomolecular NMR, 2016-03, Vol.64 (3), p.207-221

Ort / Verlag

Dordrecht: Springer Netherlands

Erscheinungsjahr

2016

Quelle

MEDLINE

Beschreibungen/Notizen

• In RNA secondary structure determination, it is essential to determine whether a nucleotide is base-paired and not. Base-pairing of nucleotides is mediated by hydrogen bonds. The NMR characterization of hydrogen bonds relies on experiments correlating the NMR resonances of exchangeable protons and can be best performed for structured parts of the RNA, where labile hydrogen atoms are protected from solvent exchange. Functionally important regions in RNA, however, frequently reveal increased dynamic disorder which often leads to NMR signals of exchangeable protons that are broadened beyond 1 H detection. Here, we develop 13 C direct detected experiments to observe all nucleotides in RNA irrespective of whether they are involved in hydrogen bonds or not. Exploiting the self-decoupling of scalar couplings due to the exchange process, the hydrogen bonding behavior of the hydrogen bond donor of each individual nucleotide can be determined. Furthermore, the adaption of HNN-COSY experiments for 13 C direct detection allows correlations of donor–acceptor pairs and the localization of hydrogen-bond acceptor nucleotides. The proposed 13 C direct detected experiments therefore provide information about molecular sites not amenable by conventional proton-detected methods. Such information makes the RNA secondary structure determination by NMR more accurate and helps to validate secondary structure predictions based on bioinformatics.