Differential stability of 2'F-ANA*RNA and ANA*RNA hybrid duplexes: roles of structure, pseudohydrogen bonding, hydration, ion uptake and flexibility.

ABSTRACT: Hybrids of RNA with arabinonucleic acids 2'F-ANA and ANA have very similar structures but strikingly different thermal stabilities. We now present a thorough study combining NMR and other biophysical methods together with state-of-the-art theoretical calculations on a fully modified 10-mer hybrid duplex. Comparison between the solution structure of 2'F-ANA*RNA and ANA*RNA hybrids indicates that the increased binding affinity of 2'F-ANA is related to several subtle differences, most importantly a favorable pseudohydrogen bond (2'F-purine H8) which contrasts with unfavorable 2'-OH-nucleobase steric interactions in the case of ANA. While both 2'F-ANA and ANA strands maintained conformations in the southern/eastern sugar pucker range, the 2'F-ANA strand's structure was more compatible with the

SUBMITTER: Watts JK 

PROVIDER: S-EPMC2853132 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature