Evidence map›Paper›PMID 12023241›Full record

ArticleBiophysical journal2002

Proton NMR studies of 5'-d-(TC)(3) (CT)(3) (AG)(3)-3'--a paperclip triplex: the structural relevance of turns.

Laura B Pasternack, Shwu-Bin Lin, Tsung-Mei Chin, Wei-Chen Lin, Dee-Hua Huang, Lou-Sing Kan

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Article in Biophysical journal, 2002. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

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2citing papers in PubMed
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3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Laura B PasternackDepartment of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA.
Shwu-Bin Lin
Tsung-Mei Chin
Wei-Chen Lin
Dee-Hua Huang
Lou-Sing Kan

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

In this study, we present the results of structural analysis of an 18-mer DNA 5'-T(1)C(2)T(3)C(4)T(5)C(6)C(7)T(8)C(9)T(10)C(11)T(12)A(13)G(14)A(15)G(16)A(17)G(18)-3' by proton nuclear magnetic resonance (NMR) spectroscopy and molecular modeling. The NMR data are consistent with characteristics for triple helical structures of DNA: downfield shifting of resonance signals, typical for the H3(+) resonances of Hoogsteen-paired cytosines; pH dependence of these H3(+) resonance; and observed nuclear Overhauser effects consistent with Hoogsteen and Watson-Crick basepairing. A three-dimensional model for the triplex is developed based on data obtained from two-dimensional NMR studies and molecular modeling. We find that this DNA forms an intramolecular "paperclip" pyrimidine-purine-pyrimidine triple helix. The central triads resemble typical Hoogsteen and Watson-Crick basepairing. The triads at each end region can be viewed as hairpin turns stabilized by a third base. One of these turns is comprised of a hairpin turn in the Watson-Crick basepairing portion of the 18-mer with the third base coming from the Hoogsteen pairing strand. The other turn is comprised of two bases from the continuous pyrimidine portion of the 18-mer, stabilized by a hydrogen-bond from a purine. This "triad" has well defined structure as indicated by the number of nuclear Overhauser effects and is shown to play a critical role in stabilizing triplex formation of the internal triads.

Indexed as

Base SequenceBiophysical PhenomenaBiophysicsCircular DichroismDNAHydrogen BondingModels, MolecularMolecular StructureNuclear Magnetic Resonance, BiomolecularNucleic Acid ConformationOligodeoxyribonucleotidesProtonsSpectrophotometry, UltravioletDNAOligodeoxyribonucleotidesProtons

Identifiers

PMID12023241
PMCPMC1302106

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.