Temporal network analysis identifies early physiological and transcriptomic indicators of mild drought in Brassica rapa

  1. Kathleen Greenham  Is a corresponding author
  2. Carmela Rosaria Guadagno  Is a corresponding author
  3. Malia A Gehan
  4. Todd C Mockler
  5. Cynthia Weinig  Is a corresponding author
  6. Brent E Ewers
  7. C. Robertson McClung  Is a corresponding author
  1. Dartmouth College, United States
  2. University of Wyoming, United States
  3. Donald Danforth Plant Science Center, United States

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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The following data sets were generated

Article and author information

Author details

  1. Kathleen Greenham

    Department of Biological Sciences, Dartmouth College, Hanover, United States
    For correspondence
    kathleen.m.greenham@dartmouth.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7681-5263
  2. Carmela Rosaria Guadagno

    Department of Botany and Program in Ecology, University of Wyoming, Laramie, United States
    For correspondence
    cguadagn@uwyo.edu
    Competing interests
    The authors declare that no competing interests exist.
  3. Malia A Gehan

    Donald Danforth Plant Science Center, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Todd C Mockler

    Donald Danforth Plant Science Center, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Cynthia Weinig

    Department of Botany and program in Ecology, University of Wyoming, Laramie, United States
    For correspondence
    cweinig@uwyo.edu
    Competing interests
    The authors declare that no competing interests exist.
  6. Brent E Ewers

    Department of Botany and Program in Ecology, University of Wyoming, Laramie, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. C. Robertson McClung

    Department of Biological Sciences, Dartmouth College, Hanover, United States
    For correspondence
    mcclung@dartmouth.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7875-3614

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.

Reviewing Editor

  1. Joerg Bohlmann, University of British Columbia, Canada

Publication history

  1. Received: June 15, 2017
  2. Accepted: August 11, 2017
  3. Accepted Manuscript published: August 18, 2017 (version 1)
  4. Version of Record published: October 4, 2017 (version 2)

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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  1. Kathleen Greenham
  2. Carmela Rosaria Guadagno
  3. Malia A Gehan
  4. Todd C Mockler
  5. Cynthia Weinig
  6. Brent E Ewers
  7. C. Robertson McClung
(2017)
Temporal network analysis identifies early physiological and transcriptomic indicators of mild drought in Brassica rapa
eLife 6:e29655.
https://doi.org/10.7554/eLife.29655
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