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Fast dynamics of supercoiled DNA revealed by single-molecule experiments.

ABSTRACT: The dynamics of supercoiled DNA play an important role in various cellular processes such as transcription and replication that involve DNA supercoiling. We present experiments that enhance our understanding of these dynamics by measuring the intrinsic response of single DNA molecules to sudden changes in tension or torsion. The observed dynamics can be accurately described by quasistatic models, independent of the degree of supercoiling initially present in the molecules. In particular, the dynamics are not affected by the continuous removal of the plectonemes. These results set an upper bound on the hydrodynamic drag opposing plectoneme removal, and thus provide a quantitative baseline for the dynamics of bare DNA.

SUBMITTER: Crut A

PROVIDER: S-EPMC1924543 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature

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Fast dynamics of supercoiled DNA revealed by single-molecule experiments.

Crut Aurélien A Koster Daniel A DA Seidel Ralf R Wiggins Chris H CH Dekker Nynke H NH

Proceedings of the National Academy of Sciences of the United States of America 20070710 29

The dynamics of supercoiled DNA play an important role in various cellular processes such as transcription and replication that involve DNA supercoiling. We present experiments that enhance our understanding of these dynamics by measuring the intrinsic response of single DNA molecules to sudden changes in tension or torsion. The observed dynamics can be accurately described by quasistatic models, independent of the degree of supercoiling initially present in the molecules. In particular, the dyn ...[more]

PMID: 17623785

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