Scientific Reports (Jul 2017)

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

  • Chao-Da Xiao,
  • Takumi Ishizuka,
  • Yan Xu

DOI
https://doi.org/10.1038/s41598-017-07050-w
Journal volume & issue
Vol. 7, no. 1
pp. 1 – 8

Abstract

Read online

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.