RNA quadruplex containing G and A.

M Katahira; K Moriyama; M Kanagawa; J Saeki; M H Kim; M Nagaoka; M Ide; S Uesugi; T Kono

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PubMed · 8841620

RNA quadruplex containing G and A.

M Katahira·K Moriyama·M Kanagawa·J Saeki·M H Kim·M Nagaoka·M Ide·S Uesugi·T Kono

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Abstract

The CD study of r(GGAGGAA) has indicated that it forms a higher order structure upon either increase of the strand concentration or addition of K+. Gel electrophoresis showed that a high molecular weight species is formed in the presence of K+. The NMR study revealed a nearly 1:1 equilibrium of two kinds of higher order structures at the strand concentration of 2.1 mM and 100 mM Na+. This equilibrium shifted drastically upon addition of K+, and only one structure remained at 40 mM K+. It is suggested that the structure formed by r(GGAGGAA) in the presence of K+ is a new type of RNA quadruplex, where an A-quartet stabilized by mutual hydrogen bonding among the four adenine bases is sandwiched by conventional G-quartets.

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Adenine Base Sequence Circular Dichroism Guanine Hydrogen Bonding Magnetic Resonance Spectroscopy Molecular Structure Nucleic Acid Conformation Oligoribonucleotides Potassium RNA Journal Article Research Support, Non-U.S. Gov't

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M Katahira, K Moriyama, M Kanagawa, J Saeki, M H Kim, M Nagaoka, M Ide, S Uesugi, T Kono. 1995. RNA quadruplex containing G and A.. https://pubmed.ncbi.nlm.nih.gov/8841620/

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