Recently, the human telomeric d[TAGGG(TTAGGG)3] sequence has been shown to form in K+ solution an intramolecular (3+1) G-quadruplex structure, whose G-tetrad core contains three strands oriented in one direction and the fourth in the opposite direction. Here we present a study on the structure of the Bombyx mori telomeric d[TAGG(TTAGG)3] sequence, which differs from the human counterpart only by one G deletion in each repeat. We found that this sequence adopted multiple G-quadruplex structures in K+ solution. We have favored a major G-quadruplex form by a judicious U-for-T substitution in the sequence and determined the folding topology of this form. We showed by NMR that this was a new chair-type intramolecular G-quadruplex which involved a two-layer antiparallel G-tetrad core and three edgewise loops. Our result highlights the effect of G-tract length on the folding topology of G-quadruplexes, but also poses the question of whether a similar chair-type G-quadruplex fold exists in the human telomeric sequences. © 2008 The Author(s).
CITATION STYLE
Amrane, S., Ang, R. W. L., Tan, Z. M., Li, C., Lim, J. K. C., Lim, J. M. W., … Phan, A. T. (2009). A novel chair-type G-quadruplex formed by a Bombyx mori telomeric sequence. Nucleic Acids Research, 37(3), 931–938. https://doi.org/10.1093/nar/gkn990
Mendeley helps you to discover research relevant for your work.