Mechanochemical properties of individual human telomeric RNA (TERRA) G-quadruplexes.

Potential functions: By following the unfolding and refolding of individual human RNA telomeric (TERRA) G-quadruplexes (GQs) in laser tweezers, the mechanical stability and transition kinetics of RNA GQs are obtained. Comparison between TERRA and DNA GQs suggests their different regulatory capacities for processes associated with human telomeres.

The kinetics and folding pathways of intramolecular G-quadruplex nucleic acids.

The folding kinetics of G-quadruplex forming sequences is critical to their capacity to influence biological function. While G-quadruplex structure and stability have been relatively well studied, little is known about the kinetics of their folding. We employed a stopped-flow mixing technique to systematically investigate the potassium-dependent folding kinetics of telomeric RNA and DNA G-quadruplexes and RNA G-quadruplexes containing only two G-quartets formed from sequences r[(GGA)(3)GG] and r[(GGUUA)(3)GG].

A sequence-independent analysis of the loop length dependence of intramolecular RNA G-quadruplex stability and topology.

G-Quadruplexes are noncanonical nucleic acid secondary structures based on guanine association that are readily adopted by G-rich RNA and DNA sequences. Naturally occurring genomic G-quadruplex-forming sequences have functional roles in biology that are mediated through structure. To appreciate how this is achieved, an understanding of the likelihood of G-quadruplex formation and the structural features of the folded species under a defined set of conditions is informative.