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Structure of a left-handed DNA G-quadruplex.

ABSTRACT: Aside from the well-known double helix, DNA can also adopt an alternative four-stranded structure known as G-quadruplex. Implications of such a structure in cellular processes, as well as its therapeutic and diagnostic applications, have been reported. The G-quadruplex structure is highly polymorphic, but so far, only right-handed helical forms have been observed. Here we present the NMR solution and X-ray crystal structures of a left-handed DNA G-quadruplex. The structure displays unprecedented features that can be exploited as unique recognition elements.

SUBMITTER: Chung WJ

PROVIDER: S-EPMC4352798 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Structure of a left-handed DNA G-quadruplex.

Chung Wan Jun WJ Heddi Brahim B Schmitt Emmanuelle E Lim Kah Wai KW Mechulam Yves Y Phan Anh Tuân AT

Proceedings of the National Academy of Sciences of the United States of America 20150218 9

Aside from the well-known double helix, DNA can also adopt an alternative four-stranded structure known as G-quadruplex. Implications of such a structure in cellular processes, as well as its therapeutic and diagnostic applications, have been reported. The G-quadruplex structure is highly polymorphic, but so far, only right-handed helical forms have been observed. Here we present the NMR solution and X-ray crystal structures of a left-handed DNA G-quadruplex. The structure displays unprecedented ...[more]

PMID: 25695967

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