13C-direct detected NMR experiments for the sequential J-based resonance assignment of RNA oligonucleotides.
We present here a set of (13)C-direct detected NMR experiments to facilitate the resonance assignment of RNA oligonucleotides. Three experiments have been developed: (1) the (H)CC-TOCSY-experiment utilizing a virtual decoupling scheme to assign the intraresidual ribose (13)C-spins, (2) the (H)CPC-experiment that correlates each phosphorus with the C4' nuclei of adjacent nucleotides via J(C,P) couplings and (3) the (H)CPC-CCH-TOCSY-experiment that correlates the phosphorus nuclei with the respective C1',H1' ribose signals. The experiments were applied to two RNA hairpin structures. The current set of (13)C-direct detected experiments allows direct and unambiguous assignment of the majority of the hetero nuclei and the identification of the individual ribose moieties following their sequential assignment. Thus, (13)C-direct detected NMR methods constitute useful complements to the conventional (1)H-detected approach for the resonance assignment of oligonucleotides that is often hindered by the limited chemical shift dispersion. The developed methods can also be applied to large deuterated RNAs.
Richter
Christian
C
Institute for Organic Chemistry and Chemical Biology, Johann Wolfgang Goethe-University Frankfurt, Frankfurt/M, Germany.
Kovacs
Helena
H
Buck
Janina
J
Wacker
Anna
A
Fürtig
Boris
B
Bermel
Wolfgang
W
Schwalbe
Harald
H
D002247:Carbon Isotopes / Q000737:chemistry*; D009587:Nitrogen Isotopes / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D009690:Nucleic Acid Conformation; D012313:RNA / Q000737:chemistry*
D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D012313:RNA