The Wg and Dpp morphogens regulate gene expression by modulating the frequency of transcriptional bursts
Abstract
Morphogen signaling contributes to the patterned spatiotemporal expression of genes during development. One mode of regulation of signaling-responsive genes is at the level of transcription. Single-cell quantitative studies of transcription have revealed that transcription occurs intermittently, in bursts. Although the effects of many gene regulatory mechanisms on transcriptional bursting have been studied, it remains unclear how morphogen gradients affect this dynamic property of downstream genes. Here we have adapted single molecule fluorescence in situ hybridization (smFISH) for use in the Drosophila wing imaginal disc in order to measure nascent and mature mRNA of genes downstream of the Wg and Dpp morphogen gradients. We compared our experimental results with predictions from stochastic models of transcription, which indicated that the transcription levels of these genes appear to share a common method of control via burst frequency modulation. Our data helps further elucidate the link between developmental gene regulatory mechanisms and transcriptional bursting.
Data availability
All smFISH data after image segmentation have been deposited in the Public Data Repository at Northwestern University's Library. These data are freely available at https://doi.org/10.21985/n2-rfax-bk36 There are no restrictions.
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Data related to Bakker et al 2020 eLife paperNorthwestern University Library Data Repository, doi.org/10.21985/n2-rfax-bk36.
Article and author information
Author details
Funding
National Institutes of Health (R35GM118144)
- Richard W Carthew
National Institutes of Health (T32CA080621)
- Rachael Bakker
National Science Foundation (1764421)
- Madhav Mani
- Richard W Carthew
Simons Foundation (597491)
- Madhav Mani
- Richard W Carthew
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Bakker 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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