Folding and misfolding pathways of G-quadruplex DNA.

ABSTRACT: G-quadruplexes adopt various folding topologies, but information on their folding pathways remains scarce. Here, we used electrospray mass spectrometry to detect and quantify the specifically bound potassium ions, and circular dichroism to characterize the stacking topology of each ensemble. For human telomeric (hTel) sequences containing the d((GGGTTA)₃GGG) core, K⁺ binding affinity and cooperativity strongly depends on the chosen construct. The shortest sequences bind only one K⁺ at low KCl concentration, and this 2-quartet G-quadruplex is antiparallel. Flanking bases increase the K⁺ binding cooperativity. To decipher the folding pathways, we investigated the kinetics of K⁺ binding to telomeric (hybrid) and c-myc (parallel) G-quadrup

SUBMITTER: Marchand A 

PROVIDER: S-EPMC5159560 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature