The influence of oligodeoxyribonucleotide phosphorothioate pyrimidine strands on triplex formation

FEBS Letters

Takaku, Hiroshi²  Yokoyama, Shigeyuki¹  Kim, Sung-Gug²  Tsukahara, Satoru² 

[1] Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan;Department of Industrial Chemistry, Chiba Institute of Technology, Tsudanuma, Narashino, Chiba 275, Japan

关键词: Triplex formation;    Phosphate modification;    T m value;    CD spectra;    Conformation;    Native polyacrylamide gel electrophoresis;   

DOI  :  10.1016/0014-5793(92)81454-T

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Analogues of the homopyrimidine oligonucleotide dT₁₅ that contained phosphorothioate bonds of a mixture of diastereoisomers or one of the two stereoisomers (either Rp or Sp) were synthesized. The analogues were mixed under conditions conducive to the formation of triple-stranded assemblies. The mixtures were characterized by their thermal stabilities (T _m values), CD spectra, and gel electrophoresis pattern. The 34-mer duplexes containing 15 central purines on one strand and 15 complementary pyrimidines on the other strand gave no detectable triple helix upon combination with dT₁₅S₁₄. On the other hand, 34-bp duplexes with dT₁₅S₁, having Rp or Sp, formed triple helixes. This suggests that a steric factor plays an important role in triple helix formation.

【 授权许可】

Unknown