Work

RapA, the SWI/SNF Subunit of Escherichia coli RNA Polymerase, Promotes the Release of Nascent RNA from Transcription Complexes

Year: 2009

Type: article

Abstract: RapA, a prokaryotic member of the SWI/SNF protein superfamily, is an integral part of the RNA polymerase transcription complex. RapA's function and catalytic mechanism have been linked to nucleic acid remodeling. In this work, we show that mutations in the interface between RapA's SWI/SNF and double-stranded nucleic acid-binding domains significantly alter ATP hydrolysis in purified RapA. The effects of individual mutations on ATP hydrolysis loosely correlated with RapA's nucleic acid remodeling activity, indicating that the interaction between these domains may be important for the RapA-mediated remodeling of nonproductive transcription complexes. In this study, we introduced a model system for in vitro transcription of a full-length Escherichia coli gene (slyD). To study the function of RapA, we fractionated and identified in vitro transcription reaction intermediates in the presence or absence of RapA. These experiments demonstrated that RapA contributes to the formation of free RNA species during in vitro transcription. This work further refines our models for RapA function in vivo and establishes a new role in RNA management for a representative of the SWI/SNF protein superfamily.

Source: Biochemistry

DOI: 10.1021/bi9004123

Authors: Brandon Yawn, Lin Zhang, Cameron Mura, Maxim V. Sukhodolets

Institutions: Lamar University, University of Virginia

Language: English

Topic: Chromatin Remodeling and Cancer

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: University of Southern California, National Institute of General Medical Sciences

Award: Substrate Specificity and Mechanism of the Bacterial SWI/SNF Protein RapA