Transcriptional rewiring over evolutionary timescales changes quantitative and qualitative properties of gene expression
- University of California, San Francisco, United States
- University of Wisconsin, United States
Abstract
Evolutionary changes in transcription networks are an important source of diversity across species, yet the quantitative consequences of network evolution have rarely been studied. Here we consider the transcriptional 'rewiring' of the three GAL genes that encode the enzymes needed for cells to convert galactose to glucose. In Saccharomyces cerevisiae, the transcriptional regulator Gal4 binds and activates these genes. In the human pathogen Candida albicans (which last shared a common ancestor with S. cerevisiae some 300 million years ago), we show that different regulators, Rtg1 and Rtg3, activate the three GAL genes. Using single-cell dynamics and RNA-sequencing, we demonstrate that although the overall logic of regulation is the same in both species-the GAL genes are induced by galactose-there are major differences in both the quantitative response of these genes to galactose and in the position of these genes in the overall transcription network structure of the two species.
Data availability
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Transcriptional Response of S. cerevisiae to Glucose and GalactosePublicly available at the NCBI Short Read Archive (accession no: SRP083773).
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Transcriptional Response of C. albicans to Glucose and GalactosePublicly available at the NCBI Short Read Archive (accession no: SRP083777).
Article and author information
Author details
Alexander D Johnson
Funding
Paul G. Allen Family Foundation
- Ignacio A Zuleta
- Hana El-Samad
National Institute of General Medical Sciences (P50 GM081879)
- Ignacio A Zuleta
- Hana El-Samad
National Institutes of Health (R01AI073289)
- Kaitlin F Mitchell
- David R Andes
National Institutes of Health (R01AI049187)
- Chiraj K Dalal
- Alexander D Johnson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All procedures in this study were approved by the Institutional Animal Care and Use Committee (IACUC) at the University of Wisconsin (protocol number MV1947) according to the guidelines of the Animal Welfare Act, and The Institute of Laboratory Animal Resources Guide for the Care and Use of Laboratory Animals and Public Health Service Policy.
Copyright
© 2016, Dalal 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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