Thermodynamic insights into 2-thiouridine-enhanced RNA hybridization.

ABSTRACT: Nucleobase modifications dramatically alter nucleic acid structure and thermodynamics. 2-thiouridine (s(2)U) is a modified nucleobase found in tRNAs and known to stabilize U:A base pairs and destabilize U:G wobble pairs. The recently reported crystal structures of s(2)U-containing RNA duplexes do not entirely explain the mechanisms responsible for the stabilizing effect of s(2)U or whether this effect is entropic or enthalpic in origin. We present here thermodynamic evaluations of duplex formation using ITC and UV thermal denaturation with RNA duplexes containing internal s(2)U:A and s(2)U:U pairs and their native counterparts. These results indicate that s(2)U stabilizes both duplexes. The stabilizing effect is entropic in origin and likely results from the s(2)U-induced preorganization o

SUBMITTER: Larsen AT 

PROVIDER: S-EPMC4652770 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature