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PNA containing isocytidine nucleobase: synthesis and recognition of double helical RNA.

ABSTRACT: Peptide nucleic acid (PNA1) containing a 5-methylisocytidine (iC) nucleobase has been synthesized. Triple helix formation between PNA1 and RNA hairpins having variable base pairs interacting with iC was studied using isothermal titration calorimetry. The iC nucleobase recognized the proposed target, C-G inversion in polypurine tract of RNA, with slightly higher affinity than the natural nucleobases, though the sequence selectivity of recognition was low. Compared to non-modified PNA, PNA1 had lower affinity for its RNA target.

SUBMITTER: Zengeya T

PROVIDER: S-EPMC3056986 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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PNA containing isocytidine nucleobase: synthesis and recognition of double helical RNA.

Zengeya Thomas T Li Ming M Rozners Eriks E

Bioorganic & medicinal chemistry letters 20110201 7

Peptide nucleic acid (PNA1) containing a 5-methylisocytidine (iC) nucleobase has been synthesized. Triple helix formation between PNA1 and RNA hairpins having variable base pairs interacting with iC was studied using isothermal titration calorimetry. The iC nucleobase recognized the proposed target, C-G inversion in polypurine tract of RNA, with slightly higher affinity than the natural nucleobases, though the sequence selectivity of recognition was low. Compared to non-modified PNA, PNA1 had lo ...[more]

PMID: 21333533

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