A physico-chemical study of triple helix formation by an oligodeoxythymidylate with N3'--> P5' phosphoramidate linkages.
Non-denaturing gel retardation assay, DNA melting experiments and FTIR spectroscopy were used to characterize the triple helix formed by a 15mer 2'-deoxythymidylate with N3'-->P5'phosphoramidate linkages with its target sequence. The results indicate that: (i) the pentadecadeoxythymidylate with phosphoramidate linkages [dT15(np)] is highly potent to form a triple helix with a dT15*dA15target duplex through Hoogsteenbase-pairing; (ii) it forms a dT15(np)*dA15xdT15(np) triplex with the single-stranded oligo-2'-deoxyadenylate (dA15) without detectable double-helical intermediate; (iii) it does not only form a triple helix on the dT15*dA15target duplex, but also partially displaces the dT15 strand from the dT15*dA15duplex to form a dT15(np)*dA15xdT15(np) complex.
Zhou-Sun
B
B
Laboratoire de Spectroscopie Biomoléculaire, CNRS URA 1430, UFR Santé Médecine Biologie Humaine, Université Paris-Nord, 74, rue Marcel Cachin, 93017 Bobigny, France.
Sun
J
J
Gryaznov
S M
SM
Liquier
J
J
Garestier
T
T
Hélène
C
C
Taillandier
E
E
D004247:DNA / Q000138:chemical synthesis* / Q000737:chemistry; D009838:Oligodeoxyribonucleotides / Q000737:chemistry*; D009943:Organophosphorus Compounds / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
D009838:Oligodeoxyribonucleotides; D009943:Organophosphorus Compounds; C027903:oligo (dT); C051802:triplex DNA; D004247:DNA