Local genetic context shapes the function of a gene regulatory network
Abstract
Gene expression levels are influenced by multiple coexisting molecular mechanisms. Some of these interactions, such as those of transcription factors and promoters have been studied extensively. However, predicting phenotypes of gene regulatory networks remains a major challenge. Here, we use a well-defined synthetic gene regulatory network to study in Escherichia coli how network phenotypes depend on local genetic context, i.e. the genetic neighborhood of a transcription factor and its relative position. We show that one gene regulatory network with fixed topology can display not only quantitatively but also qualitatively different phenotypes, depending solely on the local genetic context of its components. Transcriptional read-through is the main molecular mechanism that places one transcriptional unit within two separate regulons without the need for complex regulatory sequences. We propose that relative order of individual transcriptional units, with its potential for combinatorial complexity, plays an important role in shaping phenotypes of gene regulatory networks.
Data availability
Plasmid sequences are provided in IST Research Depository, DOI 10.15479/AT:ISTA:8951
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Sequences of gene regulatory network permutations for the article "Local genetic context shapes the function of a gene regulatory networkIST Research Depository, doi:10.15479/AT:ISTA:8951.
Article and author information
Author details
Funding
FP7 People: Marie-Curie Actions (628377)
- Anna Nagy-Staron
ANR-FWF
- Calin C Guet
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Nagy-Staron 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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