A U-tetrad stabilizes human telomeric RNA G-quadruplex structure.
Telomeric repeat-containing RNA is a new noncoding RNA molecule recently discovered in mammalian cells. Here we report the structural features of human telomere RNA r(UAGGGU) in the presence of K(+) and Na(+). We demonstrated for the first time that a novel U-tetrad is formed at the 3' end of a parallel human telomeric RNA G-quadruplex. The U-tetrad dramatically stabilizes human telomeric RNA G-quadruplex structure, leading to an increase in melting temperature (T(m)) of 29 degrees C. The U-tetrad-stabilized telomeric RNA G-quadruplex structure adds considerably to our understanding of the diversity of RNA G-quadruplex architectures. It shows that the structure of base "quartets" is important in RNA assembly. The structural information will be invaluable for understanding the function of human telomere RNA.
Xu
Yan
Y
Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan. xuyan@mkomi.rcast.u-tokyo.ac.jp
Ishizuka
Takumi
T
Kimura
Takashi
T
Komiyama
Makoto
M
D054856:G-Quadruplexes; D006801:Humans; D011188:Potassium / Q000737:chemistry; D020871:RNA Stability; D022661:RNA, Untranslated / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry; D016615:Telomere / Q000737:chemistry* / Q000235:genetics
D022661:RNA, Untranslated; D012964:Sodium; D011188:Potassium