A two-stranded template-based approach to G.(C-A) triad formation: designing novel structural elements into an existing DNA framework.

A Kettani; G Basu; A Gorin; A Majumdar; E Skripkin; D J Patel

doi:10.1006/jmbi.2000.3932

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PubMed · 10926497

A two-stranded template-based approach to G.(C-A) triad formation: designing novel structural elements into an existing DNA framework.

A Kettani·G Basu·A Gorin·A Majumdar·E Skripkin·D J Patel

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Abstract

We have designed a DNA sequence, d(G-G-G-T-T-C-A-G-G), which dimerizes to form a 2-fold symmetric G-quadruplex in which G(syn). G(anti).G(syn).G(anti) tetrads are sandwiched between all trans G. (C-A) triads. The NMR-based solution structural analysis was greatly aided by monitoring hydrogen bond alignments across N-H...N and N-H...O==C hydrogen bonds within the triad and tetrad, in a uniformly ((13)C,(15)N)-labeled sample of the d(G-G-G-T-T-C-A-G-G) sequence. The solution structure establishes that the guanine base-pairs with the cytosine through Watson-Crick G.C pair formation and with adenine through sheared G.A mismatch formation within the G.(C-A) triad. A model of triad DNA was constructed that contains the experimentally determined G.(C-A) triad alignment as the repeating stacked unit.

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Base Pair Mismatch Base Pairing Base Sequence DNA G-Quadruplexes Hydrogen Bonding Models, Molecular Molecular Sequence Data Nuclear Magnetic Resonance, Biomolecular Nucleic Acid Conformation Phosphorus Protons Structure-Activity Relationship Templates, Genetic Journal Article Research Support, U.S. Gov't, P.H.S.

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A Kettani, G Basu, A Gorin, A Majumdar, E Skripkin, D J Patel. 2000-08-04. A two-stranded template-based approach to G.(C-A) triad formation: designing novel structural elements into an existing DNA framework.. https://doi.org/10.1006/jmbi.2000.3932

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