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Antiparallel RNA G-quadruplex Formed by Human Telomere RNA Containing 8-Bromoguanosine.

ABSTRACT: In this study, by combining nuclear magnetic resonance (NMR), circular dichroism (CD), liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and gel electrophoresis, we report an unusual topological structure of the RNA G-quadruplex motif formed by human telomere RNA r(UAGGGU) containing 8-bromoguanosine. Results showed that the RNA sequence formed an antiparallel tetramolecular G-quadruplex, in which each pair of diagonal strands run in opposite directions. Furthermore, guanosines were observed both in syn- and anti-conformations. In addition, two of these G-quadruplex subunits were found to be stacking on top of each other, forming a dimeric RNA G-quadruplex. Our findings provide a new insight into the behavior of RNA G-quadruplex structures.

SUBMITTER: Xiao CD

PROVIDER: S-EPMC5532209 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Antiparallel RNA G-quadruplex Formed by Human Telomere RNA Containing 8-Bromoguanosine.

Xiao Chao-Da CD Ishizuka Takumi T Xu Yan Y

Scientific reports 20170727 1

In this study, by combining nuclear magnetic resonance (NMR), circular dichroism (CD), liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and gel electrophoresis, we report an unusual topological structure of the RNA G-quadruplex motif formed by human telomere RNA r(UAGGGU) containing 8-bromoguanosine. Results showed that the RNA sequence formed an antiparallel tetramolecular G-quadruplex, in which each pair of diagonal strands run in opposite directions. Furthermore, g ...[more]

PMID: 28751647

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