title: Highly stable triple helix formation by homopyrimidine (L)-acyclic threoninol nucleic acids with single stranded DNA and RNA.
abstract: Acyclic (L)-threoninol nucleic acid (aTNA) containing thymine, cytosine and adenine nucleobases were synthesized and shown to form surprisingly stable triplexes with complementary single stranded homopurine DNA or RNA targets. The triplex structures consist of two (L)-aTNA strands and one DNA or RNA, and these triplexes are significantly stronger than the corresponding DNA or RNA duplexes as shown in competition experiments. As a unique property the (L)-aTNAs exclusively form triplex structures with DNA and RNA and no duplex structures are observed by gel electrophoresis. The results were compared to the known enantiomer (D)-aTNA, which forms much weaker triplexes depending upon temperature and time. It was demonstrated that (L)-aTNA triplexes are able to stop primer extension on a DNA template, showing the potential of (L)-aTNA for antisense applications.
authors.affiliation: Chemical Biology Laboratory, Department of Biotechnology, Indian Institute of Technology, Madras (IITM), Chennai 600036, India. vkesavan@iitm.ac.in.
authors.forename: Vipin
authors.initials: V
authors.lastname: Kumar
authors.forename: Venkitasamy
authors.initials: V
authors.lastname: Kesavan
authors.forename: Kurt V
authors.initials: KV
authors.lastname: Gothelf
mesh_terms: D000605:Amino Alcohols / Q000138:chemical synthesis / Q000737:chemistry*; D002072:Butylene Glycols / Q000138:chemical synthesis / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry*; D008968:Molecular Conformation; D009696:Nucleic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D011743:Pyrimidines / Q000737:chemistry*; D012313:RNA / Q000737:chemistry*; D013696:Temperature
chemical_list: D000605:Amino Alcohols; D002072:Butylene Glycols; D004277:DNA, Single-Stranded; D009696:Nucleic Acids; D011743:Pyrimidines; C532652:threoninol; D012313:RNA; C030986:pyrimidine