EGFR signaling promotes the identity of Drosophila follicle stem cells via maintenance of partial cell polarity

  1. Angela Castanieto
  2. Michael J Johnston
  3. Todd G Nystul  Is a corresponding author
  1. University of California, San Francisco, United States

Abstract

Epithelial stem cells divide asymmetrically, such that one daughter replenishes the stem cell pool and the other differentiates. We found that in the epithelial follicle stem cell (FSC) lineage of the Drosophila ovary, EGFR signaling functions specifically in the FSCs to promote the unique partially polarized state of the FSC, establish apical-basal polarity throughout the lineage, and promote FSC maintenance in the niche. In addition, we identified a novel connection between EGFR signaling and the cell polarity regulator, LKB1, which indicates that EGFR signals through both the Ras-Raf-MEK-Erk pathway and through the LKB1-AMPK pathway to suppress apical identity. The development of apical-basal polarity is the earliest visible difference between FSCs and their daughters, and our findings demonstrate that the EGFR-mediated regulation of apical-basal polarity is essential for the segregation of stem cell and daughter cell fates.

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Author details

  1. Angela Castanieto

    Department of Anatomy, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Michael J Johnston

    Department of Anatomy, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Todd G Nystul

    Department of Anatomy, University of California, San Francisco, San Francisco, United States
    For correspondence
    todd.nystul@ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Castanieto 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. Angela Castanieto
  2. Michael J Johnston
  3. Todd G Nystul
(2014)
EGFR signaling promotes the identity of Drosophila follicle stem cells via maintenance of partial cell polarity
eLife 3:e04437.
https://doi.org/10.7554/eLife.04437

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https://doi.org/10.7554/eLife.04437

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