Nucleosides and nucleotides. Part 226: Alternate-strand triple-helix formation by 3′-3′-linked oligodeoxynucleotides composed of asymmetrical sequences
摘要:
In this paper, we describe the synthesis of the 3'-3'-linked oligonucleotides connected with pentaerythritol composed of asymmetrical sequences. Stability of the triplexes between these oligonucleotides and the DNA targets involving the adjacent oligopurine domains on alternate strands was investigated using the electrophoretic mobility shift assay (EMSA) and DNase I footprinting experiment. It was found that the 3'-3'-linked oligonucleotides composed of asymmetrical sequences formed the stable antiparallel triplexes with the DNA targets as compared with the unlinked oligonucleotides. Thus, oligonucleotides linked with pentaerythritol would be useful as antigene oligonucleotides for DNA targets consisting of the alternating oligopyrimidine-oligopurine sequences. (C) 2004 Elsevier Ltd. All rights reserved.
Nucleosides and Nucleotides. 182. Synthesis of Branched Oligodeoxynucleotides with Pentaerythritol at the Branch Point and Their Thermal Stabilization of Triplex Formation1
摘要:
To find an oligodeoxynucleotide (ODN) with tripler stabilization capability, we designed and synthesized novel branched ODNs I and 2 with pentaerythritols at their branch points. Branched ODNs 1 and 2 were synthesized on a solid support using bis(phosphoramidite) 11. The stability of the triplexes, formed by branched ODNs 1 and 2 with (dA)(21) or (dT)(21) was studied by thermal denaturation. Branched ODN 1 formed a stable parallel T.AT-type tripler with (dA)(21) (T-m = 38.9 degrees C) in a buffer of 0.01 M sodium phosphate (pH 7.0) containing 0.5 M NaCl and 0.02 M MgCl2, while branched ODN 2 formed a stable antiparallel A.AT-type tripler with (dT)(21) (T-m = 44.2 degrees C) in the same buffer. The formation of these triplexes was also confirmed by circular dichroism (CD) measurements and a gel retardation assay.
Nucleosides and Nucleotides. 182. Synthesis of Branched Oligodeoxynucleotides with Pentaerythritol at the Branch Point and Their Thermal Stabilization of Triplex Formation<sup>1</sup>
To find an oligodeoxynucleotide (ODN) with tripler stabilization capability, we designed and synthesized novel branched ODNs I and 2 with pentaerythritols at their branch points. Branched ODNs 1 and 2 were synthesized on a solid support using bis(phosphoramidite) 11. The stability of the triplexes, formed by branched ODNs 1 and 2 with (dA)(21) or (dT)(21) was studied by thermal denaturation. Branched ODN 1 formed a stable parallel T.AT-type tripler with (dA)(21) (T-m = 38.9 degrees C) in a buffer of 0.01 M sodium phosphate (pH 7.0) containing 0.5 M NaCl and 0.02 M MgCl2, while branched ODN 2 formed a stable antiparallel A.AT-type tripler with (dT)(21) (T-m = 44.2 degrees C) in the same buffer. The formation of these triplexes was also confirmed by circular dichroism (CD) measurements and a gel retardation assay.
Nucleosides and nucleotides. Part 226: Alternate-strand triple-helix formation by 3′-3′-linked oligodeoxynucleotides composed of asymmetrical sequences
In this paper, we describe the synthesis of the 3'-3'-linked oligonucleotides connected with pentaerythritol composed of asymmetrical sequences. Stability of the triplexes between these oligonucleotides and the DNA targets involving the adjacent oligopurine domains on alternate strands was investigated using the electrophoretic mobility shift assay (EMSA) and DNase I footprinting experiment. It was found that the 3'-3'-linked oligonucleotides composed of asymmetrical sequences formed the stable antiparallel triplexes with the DNA targets as compared with the unlinked oligonucleotides. Thus, oligonucleotides linked with pentaerythritol would be useful as antigene oligonucleotides for DNA targets consisting of the alternating oligopyrimidine-oligopurine sequences. (C) 2004 Elsevier Ltd. All rights reserved.