The universally-conserved transcription factor RfaH is recruited to a hairpin structure of the non-template DNA strand
- Universität Bayreuth, Germany
- Ohio State University, United States
Abstract
RfaH, a transcription regulator of the universally conserved NusG/Spt5 family, utilizes a unique mode of recruitment to elongating RNA polymerase to activate virulence genes. RfaH function depends critically on an ops sequence, an exemplar of a consensus pause, in the non-template DNA strand of the transcription bubble. We used structural and functional analyses to elucidate the role of ops in RfaH recruitment. Our results demonstrate that ops induces pausing to facilitate RfaH binding and establishes direct contacts with RfaH. Strikingly, the non-template DNA forms a hairpin in the RfaH:ops complex structure, flipping out a conserved T residue that is specifically recognized by RfaH. Molecular modeling and genetic evidence support the notion that ops hairpin is required for RfaH recruitment. We argue that both the sequence and the structure of the non-template strand are read out by transcription factors, expanding the repertoire of transcriptional regulators in all domains of life.
Data availability
- Diffraction data have been deposited in PDB undertake accession code 5OND.- All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 2 and 4.- The PDB file of the RfaH:ops TEC model has been provided.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (Ro 617/21-1)
- Paul Rösch
National Institutes of Health (GM67153)
- Irina Artsimovitch
Deutsche Forschungsgemeinschaft (Ro 617/17-1)
- Paul Rösch
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Zuber et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The universally-conserved transcription factor RfaH is recruited to a hairpin structure of the non-template DNA strand
eLife 7:e36349.
https://doi.org/10.7554/eLife.36349
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