Temporal network analysis identifies early physiological and transcriptomic indicators of mild drought in Brassica rapa
Abstract
The dynamics of local climates make development of agricultural strategies challenging. Yield improvement has progressed slowly, especially in drought-prone regions where annual crop production suffers from episodic aridity. Underlying drought responses are circadian and diel control of gene expression that regulate daily variations in metabolic and physiological pathways. To identify transcriptomic changes that occur in the crop Brassica rapa during initial perception of drought, we applied a co-expression network approach to associate rhythmic gene expression changes with physiological responses. Coupled analysis of transcriptome and physiological parameters over a two-day time course in control and drought-stressed plants provided temporal resolution necessary for correlation of network modules with dynamic changes in stomatal conductance, photosynthetic rate, and photosystem II efficiency. This approach enabled the identification of drought-responsive genes based on their differential rhythmic expression profiles in well-watered versus droughted networks and provided new insights into the dynamic physiological changes that occur during drought.
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Funding
National Science Foundation (IOS-1202779)
- Kathleen Greenham
Rural Development Administration (SSAC PJ01106904)
- C. Robertson McClung
National Science Foundation (IOS-1025965)
- Todd C Mockler
- Cynthia Weinig
- Brent E Ewers
- C. Robertson McClung
National Science Foundation (IOS-1547796)
- Cynthia Weinig
- Brent E Ewers
- C. Robertson McClung
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Greenham 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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