7ATZ

G-quadruplex with V-shaped loop from the first repeat of KCNN4 minisatellite

Summary for 7ATZ

• Entry DOI: 10.2210/pdb7atz/pdb
• NMR Information: BMRB: 34571
• Descriptor: DNA (5'-D(*GP*GP*TP*CP*TP*GP*AP*GP*GP*GP*AP*GP*AP*GP*GP*GP*GP*CP*TP*GP*GP*GP*T)-3') (1 entity in total)
• Functional Keywords: g-quadruplex, v-loop, dna
• Biological source: synthetic construct
• Total number of polymer chains: 1
• Total formula weight: 7298.68

Authors

Vianney, Y.M.,Weisz, K. (deposition date: 2020-11-02, release date: 2021-04-21, Last modification date: 2024-05-15)

Primary citation

Vianney, Y.M.,Weisz, K.
First Tandem Repeat of a Potassium Channel KCNN4 Minisatellite Folds into a V-Loop G-Quadruplex Structure.
Biochemistry, 60:1337-1346, 2021

PubMed Abstract: The gene encoding a potassium channel protein whose expression has been correlated with tumor progression was found to comprise a guanine-rich minisatellite region with the ability to form a putative G-quadruplex (G4). Given the suggested regulatory role of G4s in gene expression, G-quadruplex formation for the polymorphic first repeat of the minisatellite was studied by nuclear magnetic resonance spectroscopy. A stable G-quadruplex of a truncated mutant sequence was shown to represent one of several coexisting species of the wild-type sequence. The high-resolution structure features a noncanonical G4 with a broken G-column and a V-shaped loop. The presence of a 3'-flanking thymidine interacting with the lateral loop preceding the V loop seems to be critical for the formation of this G4 topology. On the contrary, an additional 5'-flanking residue disfavored but still allowed folding into the V-loop structure. The latter may therefore serve as a putative therapeutic target in strategies for G4-based modulation of expression.

PubMed: 33844501
DOI: 10.1021/acs.biochem.1c00043

Experimental method

SOLUTION NMR