DSSR-derived G-quadruplex features in PDB entry 1c32
Poster "DSSR-Enabled Automatic Identification and Annotation of G-quadruplexes in the PDB" presented at the RNA2020 online meeting
Citation: before a paper dedicated to the DSSR-G4 module comes out, please cite the 2015 DSSR paper published in Nucleic Acids Research.
- Solution structure of a quadruplex forming DNA and its intermidiate
- Marathias, V.M., Bolton, P.H.: (2000) "Structures of the potassium-saturated, 2:1, and intermediate, 1:1, forms of a quadruplex DNA." Nucleic Acids Res., 28, 1969-1977.
- Potassium can stabilize the formation of chair- or edge-type quadruplex DNA structures and appears to be the only naturally occurring cation that can do so. As quadruplex DNAs may be important in the structure of telomere, centromere, triplet repeat and other DNAs, information about the details of the potassium-quadruplex DNA interactions are of interest. The structures of the 1:1 and the fully saturated, 2:1, potassium-DNA complexes of d(GGTTGGTGTGGTTGG) have been determined using the combination of experimental NMR results and restrained molecular dynamics simulations. The refined structures have been used to model the interactions at the potassium binding sites. Comparison of the 1:1 and 2:1 potassium:DNA structures indicates how potassium binding can determine the folding pattern of the DNA. In each binding site potassium interacts with the carbonyl oxygens of both the loop thymine residues and the guanine residues of the adjacent quartet.
- G4 notes
- 2 G-tetrads, 1 G4 helix, 1 G4 stem · 2(-Lx-Lw-Ln), (2+2), UDUD
1 glyco-bond=.-s- groove=.wn. planarity=0.471 type=bowl nts=4 GGGG A.DG1,A.DG6,A.DG10,A.DG15 2 glyco-bond=-s-- groove=wn-- planarity=0.405 type=other nts=4 GGGG A.DG2,A.DG14,A.DG11,A.DG5