| 摘要 |
Hairpin triplex-forming oligonucleotides that target pyrimidine nucleic acids are disclosed. The oligonucleotides of the invention are characterized by having a duplex-forming region, a triplex-forming region, and a linker region wherein one of the internucleoside linkages between the duplex-forming and triplex-forming region is a 5'-5' or 3'-3' linkage. The duplex-forming region is comprised of purine nucleosides and has a sequence substantially complementary to a pyridine region of a target nucleic acid. The triplex-forming region is comprised of pyrimidine nucleosides and is substantially complementary in the Watson-Crick sense to the duplex-forming region. The linker region is comprised of nucleotides or other moieties that link the duplex- and triplex-forming regions. In the absence of target, the hairpin triplex-forming oligonucleotide folds back upon itself, the duplex- and triplex-forming regions running in parallel. In the presence of target nucleic acids, the duplex-forming region binds to the target by Watson-Crick bonding, and the triplex-forming region by Hoogsteen bonding, forming a triplex. The disclosed oligonucleotides display increased stability and are useful for modulating gene expression. |
