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Direct measurement of the full, sequence-dependent folding landscape of a nucleic acid.

ABSTRACT: Nucleic acid hairpins provide a powerful model system for understanding macromolecular folding, with free-energy landscapes that can be readily manipulated by changing the hairpin sequence. The full shapes of energy landscapes for the reversible folding of DNA hairpins under controlled loads exerted by an optical force clamp were obtained by deconvolution from high-resolution, single-molecule trajectories. The locations and heights of the energy barriers for hairpin folding could be tuned by adjusting the number and location of G:C base pairs, and the presence and position of folding intermediates were controlled by introducing single-nucleotide mismatches.

SUBMITTER: Woodside MT

PROVIDER: S-EPMC2656380 | biostudies-literature | 2006 Nov

REPOSITORIES: biostudies-literature

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Direct measurement of the full, sequence-dependent folding landscape of a nucleic acid.

Woodside Michael T MT Anthony Peter C PC Behnke-Parks William M WM Larizadeh Kevan K Herschlag Daniel D Block Steven M SM

Science (New York, N.Y.) 20061101 5801

Nucleic acid hairpins provide a powerful model system for understanding macromolecular folding, with free-energy landscapes that can be readily manipulated by changing the hairpin sequence. The full shapes of energy landscapes for the reversible folding of DNA hairpins under controlled loads exerted by an optical force clamp were obtained by deconvolution from high-resolution, single-molecule trajectories. The locations and heights of the energy barriers for hairpin folding could be tuned by adj ...[more]

PMID: 17095702

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