Global Regulatory Atlas Maps Transcriptional Networks in Streptomyces and Related Bacteria
Scientists have used DNA affinity purification sequencing (DAP-seq) to map genome-wide binding sites for 393 transcription factors in Streptomyces coelicolor, expanding the experimentally characterized regulatory network from roughly 8% to 50% of predicted regulators. Streptomyces and related actinomycetes are among the most prolific producers of antibiotics and other bioactive compounds, but their complex regulatory networks have been poorly understood. The resulting atlas could accelerate efforts to engineer these bacteria for improved drug discovery and biotechnology applications.
A new study published on bioRxiv presents a large-scale regulatory atlas of Streptomyces coelicolor, a model actinomycete bacterium known for producing antibiotics and other specialized metabolites. Using DAP-seq applied to 789 predicted transcription factors, the researchers generated genome-wide binding maps for 393 regulators, dramatically expanding the experimentally supported regulome from approximately 8% to 50%. Integration with ChIP-seq data revealed pleiotropic regulators and a hierarchical network architecture that links primary metabolism, developmental processes, and biosynthetic gene clusters responsible for producing bioactive compounds. The study also employed a multiplexed DAP-seq approach (multiDAP) across 16 additional actinomycete species, uncovering both deeply conserved regulatory circuits and widespread divergence in transcription factor-target interactions across the group. Together, the datasets provide a foundation for understanding how these bacteria coordinate complex phenotypes in response to environmental signals. The authors suggest the atlas will enable predictive modeling and rational engineering of actinomycetes for applications in medicine and industrial biotechnology.
What's missing
As a preprint, this work has not yet undergone formal peer review, so findings should be interpreted with appropriate caution. DAP-seq is an in vitro method and may not fully capture in vivo transcription factor binding dynamics, including the influence of cofactors, chromatin state, or post-translational modifications. The study does not directly demonstrate functional outcomes of the newly identified regulatory interactions, leaving causal relationships between transcription factor binding and gene expression largely inferred. Coverage remains incomplete, as binding data were obtained for only 393 of 789 predicted transcription factors, and the biological significance of many newly mapped interactions remains to be validated experimentally.
What different sources said
- bioRxivCenter
A global regulatory atlas of Streptomyces reveals conserved and diversified transcriptional networks across actinomycetes
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