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LNA units present in [R _P-PS]-(DNA#LNA) chimeras enhance the thermal stability of parallel duplexes and triplexes formed with (2'-OMe)-RNA strands.

ABSTRACT: The results of CD measurements indicate that 2-4 LNA units distributed along 12 nt P-stereodefined phosphorothioate [R _P-PS]-(DNA#LNA) chimeras impose a C3'-endo conformation on the 2'-deoxyribonucleosides. Under neutral and slightly acidic conditions homopurine [R _p-PS]-(DNA#LNA) hybridizes with 9-12 nt Hoogsteen-paired (2'-OMe)-RNA strands to form parallel duplexes, which are thermally more stable than the reported earlier analogous complexes containing LNA-free [R _P-PS]-DNA oligomers (ΔT _m = 7 °C per LNA unit at pH 5.4). Upon addition of the corresponding Watson-Crick-paired (2'-OMe)-RNA strands, parallel triplexes are formed with further increased thermal stability.

SUBMITTER: Jastrzebska K

PROVIDER: S-EPMC9054617 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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LNA units present in [R P-PS]-(DNA#LNA) chimeras enhance the thermal stability of parallel duplexes and triplexes formed with (2'-OMe)-RNA strands.

Jastrzębska Katarzyna K Mikołajczyk Barbara B Guga Piotr P

RSC advances 20200610 38

The results of CD measurements indicate that 2-4 LNA units distributed along 12 nt P-stereodefined phosphorothioate [R P-PS]-(DNA#LNA) chimeras impose a C3'-endo conformation on the 2'-deoxyribonucleosides. Under neutral and slightly acidic conditions homopurine [R p-PS]-(DNA#LNA) hybridizes with 9-12 nt Hoogsteen-paired (2'-OMe)-RNA strands to form parallel duplexes, which are thermally more stable than the reported earlier analogous complexes containi ...[more]

PMID: 35514591

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