Influence of the sugar configuration on the structure of RNA by conformational analysis of the ribose-phosphate unit

✍ Scribed by H. Broch; R. Cornillon; J. N. Lespinasse; D. Vasilescu

• Publisher: Wiley (John Wiley & Sons)
• Year: 1975
• Tongue: English
• Weight: 752 KB
• Volume: 14
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1975.360140403

✦ Synopsis

Abstract

The conformation of the ribose‐phosphate unit for the four principal configurations of the sugar ring has been studied using the extended Hückel theory and the Lennard–Jones empirical potential. Initially, the oxygen atoms of the p3 and p5 groups were not taken into account. With this restriction, the energy of this residue with regard to the structure of RNA has been minimized for the rotational angles ψ and ϕ′.

The equivalence of the sugar puckering C2′endo ≃ C3′exo and C3′endo ≃ C2′exo has been confirmed. We find that the role of the sugar configuration is important and that there is a difference in the rotations around the bond C3′‐O3′ (ϕ′ angle) according to this configuration. The C3′endo sugar form seems to be energetically preferred for this residue of RNA.

The oxygen atoms and the electrostatic interactions were then introduced into the empirical potential. The variation of the energy when varying ϕ′ for different positions of the p5 group was studied for the main C3′endo and C2′endo configurations of the sugar; in this condition the ϕ′ rotation is considerably restricted but the allowed regions continue to differ according to the configuration of the sugar considered.