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Dynamics and stability of polymorphic human telomeric G-quadruplex under tension.

ABSTRACT: As critical DNA structures capping the human chromosome ends, the stability and structural polymorphism of human telomeric G-quadruplex (G4) have drawn increasing attention in recent years. This work characterizes the equilibrium transitions of single-molecule telomeric G4 at physiological K(+) concentration. We report three folded states of telomeric G4 with markedly different lifetime and mechanical stability. Our results show that the kinetically favored folding pathway is through a short-lived intermediate state to a longer-lived state. By examining the force dependence of transition rates, the force-dependent transition free energy landscape for this pathway is determined. In addition, an ultra-long-lived form of telomeric G4 structure with a much stronger mechanical stability is identified.

SUBMITTER: You H

PROVIDER: S-EPMC4117794 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Dynamics and stability of polymorphic human telomeric G-quadruplex under tension.

You Huijuan H Zeng Xiangjun X Xu Yue Y Lim Ci Ji CJ Efremov Artem K AK Phan Anh Tuân AT Yan Jie J

Nucleic acids research 20140710 13

As critical DNA structures capping the human chromosome ends, the stability and structural polymorphism of human telomeric G-quadruplex (G4) have drawn increasing attention in recent years. This work characterizes the equilibrium transitions of single-molecule telomeric G4 at physiological K(+) concentration. We report three folded states of telomeric G4 with markedly different lifetime and mechanical stability. Our results show that the kinetically favored folding pathway is through a short-liv ...[more]

PMID: 25013179

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