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RNA polymerase can track a DNA groove during promoter search.

ABSTRACT: Many proteins select special DNA sequences to form functional complexes. In one possible mechanism, protein molecules would scan DNA sequences by tracking a groove without complete dissociation. Upon dragging single molecules of DNA over a surface carrying fixed Escherichia coli RNA polymerase holoenzyme, we detected rotation of individual DNA molecules, providing direct evidence that a DNA-binding protein can track a DNA groove. These results confirm our previous observations of longitudinal movement of RNA polymerase along fixed, extended DNA and, moreover, imply that groove tracking facilitates scanning of DNA sequences.

SUBMITTER: Sakata-Sogawa K

PROVIDER: S-EPMC522051 | biostudies-literature | 2004 Oct

REPOSITORIES: biostudies-literature

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RNA polymerase can track a DNA groove during promoter search.

Sakata-Sogawa Kumiko K Shimamoto Nobuo N

Proceedings of the National Academy of Sciences of the United States of America 20041006 41

Many proteins select special DNA sequences to form functional complexes. In one possible mechanism, protein molecules would scan DNA sequences by tracking a groove without complete dissociation. Upon dragging single molecules of DNA over a surface carrying fixed Escherichia coli RNA polymerase holoenzyme, we detected rotation of individual DNA molecules, providing direct evidence that a DNA-binding protein can track a DNA groove. These results confirm our previous observations of longitudinal mo ...[more]

PMID: 15469913

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