1. Plant Biology
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Synthetic hormone-responsive transcription factors can monitor and re-program plant development

  1. Arjun Khakhar
  2. Alexander R Leydon
  3. Andrew C Lemmex
  4. Eric Klavins
  5. Jennifer L Nemhauser  Is a corresponding author
  1. University of Washington, United States
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Cite this article as: eLife 2018;7:e34702 doi: 10.7554/eLife.34702

Abstract

Developmental programs sculpt plant morphology to meet environmental challenges, and these same programs have been manipulated to increase agricultural productivity1,2. Hormones coordinate these programs, creating chemical circuitry3 that has been represented in mathematical models4,5; however, model-guided engineering of plant morphology has been limited by a lack of tools6,7. Here, we introduce a novel set of synthetic and modular hormone activated Cas9-based repressors (HACRs) in Arabidopsis thaliana that respond to three hormones: auxin, gibberellins and jasmonates. We demonstrate that HACRs are sensitive to both exogenous hormone treatments and local differences in endogenous hormone levels associated with development. We further show that this capability can be leveraged to reprogram development in an agriculturally relevant manner by changing how the hormonal circuitry regulates target genes. By deploying a HACR to re-parameterize the auxin-induced expression of the auxin transporter PIN-FORMED1 (PIN1), we decreased shoot branching and phyllotactic noise, as predicted by existing models4,5.

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Author details

  1. Arjun Khakhar

    Department of Electrical Engineering, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4676-6533

  2. Alexander R Leydon

    Department of Biology, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Andrew C Lemmex

    Department of Biology, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Eric Klavins

    Department of Electrical Engineering, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Jennifer L Nemhauser

    Department of Biology, University of Washington, Seattle, United States
    For correspondence
    jn7@uw.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8909-735X

Funding

National Science Foundation (MCB-1411949)

  • Eric Klavins

National Institutes of Health (R01-GM107084)

  • Jennifer L Nemhauser

Howard Hughes Medical Institute (Faculty Scholars Program)

  • Jennifer L Nemhauser

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Dominique C Bergmann, Stanford University/HHMI, United States

Publication history

  1. Received: January 2, 2018
  2. Accepted: April 30, 2018
  3. Accepted Manuscript published: May 1, 2018 (version 1)
  4. Version of Record published: May 30, 2018 (version 2)

Copyright

© 2018, Khakhar 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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