DSSR-PyMOL cartoon-block schematics: PDB entry 6jce

PDB-id

6jce; DSSR-derived features in text and JSON formats

Class

DNA

Method

NMR

Summary

NMR solution and x-ray crystal structures of a DNA containing both right-and left-handed parallel-stranded g-quadruplexes

Reference

Winnerdy FR, Bakalar B, Maity A, Vandana JJ, Mechulam Y, Schmitt E, Phan AT (2019): "NMR solution and X-ray crystal structures of a DNA molecule containing both right- and left-handed parallel-stranded G-quadruplexes." Nucleic Acids Res., 47, 8272-8281. doi: 10.1093/nar/gkz349.

Abstract

Analogous to the B- and Z-DNA structures in double-helix DNA, there exist both right- and left-handed quadruple-helix (G-quadruplex) DNA. Numerous conformations of right-handed and a few left-handed G-quadruplexes were previously observed, yet they were always identified separately. Here, we present the NMR solution and X-ray crystal structures of a right- and left-handed hybrid G-quadruplex. The structure reveals a stacking interaction between two G-quadruplex blocks with different helical orientations and displays features of both right- and left-handed G-quadruplexes. An analysis of loop mutations suggests that single-nucleotide loops are preferred or even required for the left-handed G-quadruplex formation. The discovery of a right- and left-handed hybrid G-quadruplex further expands the polymorphism of G-quadruplexes and is potentially useful in designing a left-to-right junction in G-quadruplex engineering.