Work

Initial Transcription by RNA Polymerase Proceeds Through a DNA-Scrunching Mechanism

Year: 2006

Type: article

Abstract: Using fluorescence resonance energy transfer to monitor distances within single molecules of abortively initiating transcription initiation complexes, we show that initial transcription proceeds through a "scrunching" mechanism, in which RNA polymerase (RNAP) remains fixed on promoter DNA and pulls downstream DNA into itself and past its active center. We show further that putative alternative mechanisms for RNAP active-center translocation in initial transcription, involving "transient excursions" of RNAP relative to DNA or "inchworming" of RNAP relative to DNA, do not occur. The results support a model in which a stressed intermediate, with DNA-unwinding stress and DNA-compaction stress, is formed during initial transcription, and in which accumulated stress is used to drive breakage of interactions between RNAP and promoter DNA and between RNAP and initiation factors during promoter escape.

Source: Science

DOI: 10.1126/science.1131399

Authors: Achillefs N. Kapanidis, Emmanuel Margeat, Sam On Ho, Ekaterine Kortkhonjia, Shimon Weiss, Richard H. Ebright

Institutions: Rutgers, The State University of New Jersey, Howard Hughes Medical Institute, University of California, Los Angeles, University of Oxford

Language: English

Topic: Genomics and Chromatin Dynamics

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: Howard Hughes Medical Institute, National Institute of General Medical Sciences

Awards: G2329670502, BACTERIAL TRANSCRIPTION COMPLEXES, Single Molecule Studies of Prokaryotic and Eukaryotic Transcription Machineries, G682642941, Prokaryotic Transcription Termination R37GM041376-R01GM041376 - Competitive Renewal Resubmission 1