The DBL-1/TGF-β signaling pathway tailors behavioral and molecular host responses to a variety of bacteria in Caenorhabditis elegans

  1. Bhoomi Madhu
  2. Mohammed Farhan Lakdawala
  3. Tina L Gumienny  Is a corresponding author
  1. Texas Woman's University, United States

Abstract

Generating specific, robust protective responses to different bacteria is vital for animal survival. Here, we address the role of transforming growth factor β (TGF-β) member DBL-1 in regulating signature host defense responses in Caenorhabditis elegans to human opportunistic Gram-negative and Gram-positive pathogens. Canonical DBL-1 signaling is required to suppress avoidance behavior in response to Gram-negative, but not Gram-positive bacteria. We propose that in the absence of DBL-1, animals perceive some bacteria as more harmful. Animals activate DBL-1 pathway activity in response to Gram-negative bacteria and strongly repress it in response to select Gram-positive bacteria, demonstrating bacteria-responsive regulation of DBL-1 signaling. DBL-1 signaling differentially regulates expression of target innate immunity genes depending on the bacterial exposure. These findings highlight a central role for TGF-β in tailoring a suite of bacteria-specific host defenses.

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All data generated or analysed during this study are included in the manuscript and supporting file.

Article and author information

Author details

  1. Bhoomi Madhu

    Department of Biology, Texas Woman's University, Denton, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Mohammed Farhan Lakdawala

    Department of Biology, Texas Woman's University, Denton, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Tina L Gumienny

    Department of Biology, Texas Woman's University, Denton, United States
    For correspondence
    tgumienny@twu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3932-7815

Funding

Office of Extramural Research, National Institutes of Health (R01GM097591)

  • Tina L Gumienny

Jane Nelson Institute for Women's Leadership (internal grant)

  • Tina L Gumienny

TWU Research Enhancement Program (faculty grant)

  • Tina L Gumienny

TWU Experiential Learning Scholar Award (student funding)

  • Bhoomi Madhu

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

Copyright

© 2023, Madhu 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. Bhoomi Madhu
  2. Mohammed Farhan Lakdawala
  3. Tina L Gumienny
(2023)
The DBL-1/TGF-β signaling pathway tailors behavioral and molecular host responses to a variety of bacteria in Caenorhabditis elegans
eLife 12:e75831.
https://doi.org/10.7554/eLife.75831

Share this article

https://doi.org/10.7554/eLife.75831

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