1. Genetics and Genomics
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Gene regulatory network plasticity predates a switch in function of a conserved transcription regulator

  1. Isabel Nocedal  Is a corresponding author
  2. Eugenio Mancera
  3. Alexander D Johnson  Is a corresponding author
  1. Massachusetts Institute of Technology, United States
  2. Cinvestav Unidad Irapuato, Mexico
  3. University of California, San Francisco, United States
Research Article
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Cite this article as: eLife 2017;6:e23250 doi: 10.7554/eLife.23250


The rewiring of gene regulatory networks can generate phenotypic novelty. It remains an open question, however, how the large number of connections needed to form a novel network arise over evolutionary time. Here we address this question using the network controlled by the fungal transcription regulator Ndt80. This conserved protein has undergone a dramatic switch in function—from an ancestral role regulating sporulation to a derived role regulating biofilm formation. This switch in function corresponded to a large-scale rewiring of the genes regulated by Ndt80. However, we demonstrate that the Ndt80-target gene connections were undergoing extensive rewiring prior to the switch in Ndt80’s regulatory function. We propose that extensive drift in the Ndt80 regulon allowed for the exploration of alternative network structures without a loss of ancestral function, thereby facilitating the formation of a network with a new function.

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The following previously published data sets were used

Article and author information

Author details

  1. Isabel Nocedal

    Department of Biology, Massachusetts Institute of Technology, Cambridge, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4706-1113
  2. Eugenio Mancera

    Departamento de Ingeniería Genética, Cinvestav Unidad Irapuato, Irapuaro, Mexico
    Competing interests
    The authors declare that no competing interests exist.
  3. Alexander D Johnson

    Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.


National Institutes of Health (R01 GM037049)

  • Isabel Nocedal
  • Eugenio Mancera
  • Alexander D Johnson

Human Frontier Science Program

  • Eugenio Mancera


  • Eugenio Mancera

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

Reviewing Editor

  1. Patricia J Wittkopp, University of Michigan, United States

Publication history

  1. Received: November 12, 2016
  2. Accepted: March 21, 2017
  3. Accepted Manuscript published: March 22, 2017 (version 1)
  4. Version of Record published: April 13, 2017 (version 2)


© 2017, Nocedal 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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