Gene Silencing Activity of siRNAs with a Ribo-difluorotoluyl Nucleotide
Citations Over TimeTop 10% of 2006 papers
Abstract
Recently, chemically synthesized short interfering RNA (siRNA) duplexes have been used with success for gene silencing. Chemical modification is desired for therapeutic applications to improve biostability and pharmacokinetic properties; chemical modification may also provide insight into the mechanism of silencing. siRNA duplexes containing the 2,4-difluorotoluyl ribonucleoside (rF) were synthesized to evaluate the effect of noncanonical nucleoside mimetics on RNA interference. 5'-Modification of the guide strand with rF did not alter silencing relative to unmodified control. Internal uridine to rF substitutions were well-tolerated. Thermal melting analysis showed that the base pair between rF and adenosine (A) was destabilizing relative to a uridine-adenosine pair, although it was slightly less destabilizing than other mismatches. The crystal structure of a duplex containing rFoA pairs showed local structural variations relative to a canonical RNA helix. As the fluorine atoms cannot act as hydrogen bond acceptors and are more hydrophobic than uridine, there was an absence of a well-ordered water structure around the rF residues in both grooves. siRNAs with the rF modification effectively silenced gene expression and offered improved nuclease resistance in serum; therefore, evaluation of this modification in therapeutic siRNAs is warranted.
Related Papers
- → Uridine-induced hypothermia in mice and rats in relation to plasma and tissue levels of uridine and its metabolites(1987)83 cited
- → Uridine Transport and Metabolism in the Central Nervous System(1985)37 cited
- → Characterization of immobilized nuclease P1(2007)11 cited
- → Similarities and differences in the properties of alfalfa endonucleases(1998)10 cited
- → Stimulation of uridine uptake in 3T3 cells is associated with increased ATP affinity of uridine-phosphorylating system(1978)20 cited