Variation in the modality of a yeast signaling pathway is mediated by a single regulator

  1. Julius Palme
  2. Jue Wang
  3. Michael Springer  Is a corresponding author
  1. Harvard Medical School, United States
  2. University of Washington, United States

Abstract

Bimodal gene expression by genetically identical cells is a pervasive feature of signaling networks, and has been suggested to allow organisms to hedge their "bets" in uncertain conditions. In the galactose-utilization (GAL) pathway of Saccharomyces cerevisiae, gene induction is unimodal or bimodal depending on natural genetic variation and pre-induction conditions. Here, we find that this variation in modality arises from regulation of two features of the pathway response: the fraction of cells that show induction, and their level of expression. GAL3, the galactose sensor, controls the fraction of induced cells, and titrating its expression is sufficient to control modality; moreover, all the observed differences in modality between different pre-induction conditions and amongst natural isolates can be explained by changes in GAL3's regulation and activity. The ability to switch modality by tuning the activity of a single protein may allow rapid adaptation of bet hedging to maximize fitness in complex environments.

Data availability

All data is deposited in a Dyrad repository (https://doi.org/10.5061/dryad.69p8cz8z8

The following data sets were generated

Article and author information

Author details

  1. Julius Palme

    Harvard Medical School, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5897-1334
  2. Jue Wang

    Department of Chemical Engineering, University of Washington, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Michael Springer

    Harvard Medical School, Boston, United States
    For correspondence
    michael_springer@hms.harvard.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3970-6380

Funding

National Science Foundation (MCB-1349248)

  • Jue Wang
  • Michael Springer

National Institutes of Health (GM120122)

  • Julius Palme
  • Michael Springer

National Science Foundation (DGE1144152)

  • Jue Wang

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

Reviewing Editor

  1. Detlef Weigel, Max Planck Institute for Developmental Biology, Germany

Version history

  1. Preprint posted: April 28, 2017 (view preprint)
  2. Received: May 3, 2021
  3. Accepted: July 10, 2021
  4. Accepted Manuscript published: August 9, 2021 (version 1)
  5. Version of Record published: August 18, 2021 (version 2)

Copyright

© 2021, Palme 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. Julius Palme
  2. Jue Wang
  3. Michael Springer
(2021)
Variation in the modality of a yeast signaling pathway is mediated by a single regulator
eLife 10:e69974.
https://doi.org/10.7554/eLife.69974

Share this article

https://doi.org/10.7554/eLife.69974

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