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Single molecule analysis of RNA polymerase elongation reveals uniform kinetic behavior.

ABSTRACT: By using single-molecule measurements, we demonstrate that the elongation kinetics of individual Escherichia coli RNA polymerase molecules are remarkably homogeneous. We find no evidence of distinct elongation states among RNA polymerases. Instead, the observed heterogeneity in transcription rates results from statistical variation in the frequency and duration of pausing. When transcribing a gene without strong pause sites, RNA polymerase molecules display transient pauses that are distributed randomly in both time and distance. Transitions between the active elongation mode and the paused state are instantaneous within the resolution of our measurements (<1 s). This elongation behavior is compared with that of a mutant RNA polymerase that pauses more frequently and elongates more slowly than wild type.

SUBMITTER: Adelman K

PROVIDER: S-EPMC129709 | biostudies-literature | 2002 Oct

REPOSITORIES: biostudies-literature

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Single molecule analysis of RNA polymerase elongation reveals uniform kinetic behavior.

Adelman Karen K La Porta Arthur A Santangelo Thomas J TJ Lis John T JT Roberts Jeffrey W JW Wang Michelle D MD

Proceedings of the National Academy of Sciences of the United States of America 20021007 21

By using single-molecule measurements, we demonstrate that the elongation kinetics of individual Escherichia coli RNA polymerase molecules are remarkably homogeneous. We find no evidence of distinct elongation states among RNA polymerases. Instead, the observed heterogeneity in transcription rates results from statistical variation in the frequency and duration of pausing. When transcribing a gene without strong pause sites, RNA polymerase molecules display transient pauses that are distributed ...[more]

PMID: 12370445

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