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Hoogsteen-paired homopurine [RP-PS]-DNA and homopyrimidine RNA strands form a thermally stable parallel duplex.

ABSTRACT: Homopurine deoxyribonucleoside phosphorothioates possessing all internucleotide linkages of R(P) configuration form a duplex with an RNA or 2'-OMe-RNA strand with Hoogsteen complementarity. The duplexes formed with RNA templates are thermally stable at pH 5.3, while those formed with a 2'-OMe-RNA are stable at neutrality. Melting temperature and fluorescence quenching experiments indicate that the strands are parallel. Remarkably, these duplexes are thermally more stable than parallel Hoogsteen duplexes and antiparallel Watson-Crick duplexes formed by unmodified homopurine DNA molecules of the same sequence with corresponding RNA templates.

SUBMITTER: Guga P

PROVIDER: S-EPMC2072079 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature

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Hoogsteen-paired homopurine [RP-PS]-DNA and homopyrimidine RNA strands form a thermally stable parallel duplex.

Guga Piotr P Janicka Magdalena M Maciaszek Anna A Rebowska Beata B Nowak Genowefa G

Biophysical journal 20070810 10

Homopurine deoxyribonucleoside phosphorothioates possessing all internucleotide linkages of R(P) configuration form a duplex with an RNA or 2'-OMe-RNA strand with Hoogsteen complementarity. The duplexes formed with RNA templates are thermally stable at pH 5.3, while those formed with a 2'-OMe-RNA are stable at neutrality. Melting temperature and fluorescence quenching experiments indicate that the strands are parallel. Remarkably, these duplexes are thermally more stable than parallel Hoogsteen ...[more]

PMID: 17693472

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