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Properties of triple helices formed by parallel-stranded hairpins containing 8-aminopurines.

ABSTRACT: Parallel-stranded hairpins with a polypyrimidine sequence linked to a complementary purine carrying 8-aminopurines such as 8-aminoadenine, 8-aminoguanine and 8-aminohypoxanthine bind polypyrimidine sequences complementary (in an antiparallel sense) to the purine part by a triple helix. The relative stabilities of triplexes were assessed by UV-absorption melting experiments as a function of pH and salt concentration. Hairpins carrying 8-aminopurines give very stable triple helical structures even at neutral pH, as confirmed by gel-shift experiments, circular dichroism and nuclear magnetic resonance spectroscopy. The modified hairpins may be redesigned to cope with small interruptions in the polypyrimidine target sequence.

SUBMITTER: Avino A

PROVIDER: S-EPMC117286 | biostudies-literature | 2002 Jun

REPOSITORIES: biostudies-literature

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Properties of triple helices formed by parallel-stranded hairpins containing 8-aminopurines.

Aviñó Anna A Frieden Miriam M Morales Juan Carlos JC García de la Torre Beatriz B Güimil García Ramón R Azorín Ferran F Gelpí José Luis JL Orozco Modesto M González Carlos C Eritja Ramon R

Nucleic acids research 20020601 12

Parallel-stranded hairpins with a polypyrimidine sequence linked to a complementary purine carrying 8-aminopurines such as 8-aminoadenine, 8-aminoguanine and 8-aminohypoxanthine bind polypyrimidine sequences complementary (in an antiparallel sense) to the purine part by a triple helix. The relative stabilities of triplexes were assessed by UV-absorption melting experiments as a function of pH and salt concentration. Hairpins carrying 8-aminopurines give very stable triple helical structures even ...[more]

PMID: 12060677

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