Spectroscopic evidence for an intramolecular RNA triple helix.
A 29-base RNA oligomer has been chemically synthesized and shown to form an intramolecular triple helix in solution at acidic pH. Assignment of the majority of the exchangeable proton NMR resonances demonstrated the Watson-Crick and Hoogsteen base pairings consistent with folding to form pyrimidine-purine-pyrimidine base triplets. FTIR spectroscopy provided independent evidence of base triplet formation, and indicated a predominately C3'-endo sugar pucker. UV absorption as a function of temperature suggested monophasic melting behaviour, which was confirmed by NMR of the imino protons.
Klinck
R
R
Institut de Chimie des Substances Naturelles, CNRS, Gif-sur-Yvette, France.
Guittet
E
E
Liquier
J
J
Taillandier
E
E
Gouyette
C
C
Huynh-Dinh
T
T
D000143:Acids; D001483:Base Sequence; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D012313:RNA / Q000737:chemistry*; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
D000143:Acids; D012996:Solutions; D012313:RNA