Thermosensitive alternative splicing senses and mediates temperature adaptation in Drosophila
- Brandeis University, United States
- The Hebrew University of Jerusalem, Israel
Abstract
Circadian rhythms are generated by cyclic transcription, translation, and degradation of clock gene products, including timeless (tim), but how the circadian clock senses and adapts to temperature changes is not completely understood. Here we show that temperature dramatically changes the splicing pattern of tim in Drosophila. We found that at 18 °C, TIM levels are low due to the induction of two cold-specific isoforms: tim-cold and tim-short&cold. At 29 °C, another isoform, tim-medium, is upregulated. This isoform switching regulates the levels and activity of TIM as each isoform has a specific function. We found that tim-short&cold encodes a protein that rescues the behavioral defects of tim01 mutants and that flies in which tim-short&cold is abrogated have abnormal locomotor activity. In addition, miRNA-mediated control limits the expression of some of these isoforms. Finally, our data using minigenes suggest that tim alternative splicing might act as a thermometer for the circadian clock.
Data availability
Sequencing data have been deposited in GEO under accession codes GSE124134, 124135, 124141, 123142, 124200 and 124201.
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Small RNA seq from Ago1-IP of fly heads at different temperatures and circadian timepointsNCBI Gene Expression Omnibus, GSE124134.
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total mRNA seq from fly heads at different temperatures and circadian timepointsNCBI Gene Expression Omnibus, GSE124135.
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3' end RNA seq from fly heads at different temperatures and circadian timepointsNCBI Gene Expression Omnibus, GSE124141.
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Total RNA from different species fly headsNCBI Gene Expression Omnibus, GSE123142.
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3' end RNA seq from fly heads at different temperatures and circadian timepointsNCBI Gene Expression Omnibus, GSE124200.
Article and author information
Author details
Funding
National Institutes of Health (R01GM125859)
- Sebastian Kadener
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Martin Anduaga 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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Thermosensitive alternative splicing senses and mediates temperature adaptation in Drosophila
eLife 8:e44642.
https://doi.org/10.7554/eLife.44642
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