Chromatin mapping identifies BasR, a key regulator of bacteria-triggered production of fungal secondary metabolites
Abstract
The eukaryotic epigenetic machinery can be modified by bacteria to reprogram the response of eukaryotes during their interaction with microorganisms. We discovered that the bacterium Streptomyces rapamycinicus triggered increased chromatin acetylation and thus activation of the silent secondary metabolism ors gene cluster in the fungus Aspergillus nidulans. Using this model we aim at understanding mechanisms of microbial communication based on bacteria-triggered chromatin modification. By genome-wide ChIP-seq analysis of acetylated histone H3 we uncovered the unique chromatin landscape in A. nidulans upon co-cultivation with S. rapamycinicus and relate changes in the acetylation to that in the fungal transcriptome. Differentially acetylated histones were detected in genes involved in secondary metabolism, amino acid and nitrogen metabolism, signaling, and encoding transcription factors. Further molecular analyses identified the Myb-like transcription factor BasR as the regulatory node for transduction of the bacterial signal in the fungus and show its function is conserved in other Aspergillus species.
Data availability
ChIP-seq data were deposited in the ArrayExpress database at EMBL-EBI (www.ebi.ac.uk/arrayexpress) under accession number E-MTAB-5819.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (SFB 1127)
- Tina Netzker
- Nils Jäger
- Ekaterina Shelest
Bundesministerium für Bildung und Forschung (InfectControl2020)
- Maria C Stroe
Horizon 2020 Framework Programme (IF-EF; Project reference 700036)
- María García-Altares
Leibniz-Gemeinschaft
- Juliane Fischer
Deutsche Forschungsgemeinschaft (GSC 214)
- Mario KC Krespach
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Antonis Rokas, Vanderbilt University, United States
Version history
- Received: August 10, 2018
- Accepted: October 11, 2018
- Accepted Manuscript published: October 12, 2018 (version 1)
- Version of Record published: November 13, 2018 (version 2)
Copyright
© 2018, Fischer 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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