Stabilizing contributions of sulfur-modified nucleotides: crystal structure of a DNA duplex with 2'-O-[2-(methoxy)ethyl]-2-thiothymidines.

ABSTRACT: Substitution of oxygen atoms by sulfur at various locations in the nucleic acid framework has led to analogs such as the DNA phosphorothioates and 4'-thio RNA. The phosphorothioates are excellent mimics of DNA, exhibit increased resistance to nuclease degradation compared with the natural counterpart, and have been widely used as first-generation antisense nucleic acid analogs for applications in vitro and in vivo. The 4'-thio RNA analog exhibits significantly enhanced RNA affinity compared with RNA, and shows potential for incorporation into siRNAs. 2-Thiouridine (s2U) and 5-methyl-2-thiouridine (m5s2U) are natural nucleotide analogs. s2U in tRNA confers greater specificity of codon-anticodon interactions by discriminating more strongly between A and G compared with U. 2-Thio modification

SUBMITTER: Diop-Frimpong B 

PROVIDER: S-EPMC1216336 | biostudies-literature | 2005

REPOSITORIES: biostudies-literature