Cell-cycle quiescence maintains C. elegans germline stem cells independent of GLP-1/Notch

  1. Hannah S Seidel  Is a corresponding author
  2. Judith Kimble
  1. University of Wisconsin-Madison, United States

Abstract

Many types of adult stem cells exist in a state of cell-cycle quiescence, yet it has remained unclear whether quiescence plays a role in maintaining the stem cell fate. Here we establish the adult germline of C. elegans as model for facultative stem cell quiescence. We find that mitotically dividing germ cells-including germline stem cells-become quiescent in the absence of food. This quiescence is characterized by a slowing of S phase, a block to M-phase entry, and the ability to re-enter M phase rapidly in response to re-feeding. Further, we demonstrate that cell-cycle quiescence alters the genetic requirements for stem cell maintenance: The signaling pathway required for stem cell maintenance under fed conditions-GLP-1/Notch signaling-becomes dispensable under conditions of quiescence. Thus, cell-cycle quiescence can itself maintain stem cells, independent of the signaling pathway otherwise essential for such maintenance.

Article and author information

Author details

  1. Hannah S Seidel

    Department of Biochemistry, University of Wisconsin-Madison, Madison, United States
    For correspondence
    hsseidel@wisc.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Judith Kimble

    Department of Biochemistry, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Alejandro Sánchez Alvarado, Stowers Institute for Medical Research, United States

Version history

  1. Received: August 13, 2015
  2. Accepted: November 7, 2015
  3. Accepted Manuscript published: November 9, 2015 (version 1)
  4. Version of Record published: January 7, 2016 (version 2)

Copyright

© 2015, Seidel & Kimble

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. Hannah S Seidel
  2. Judith Kimble
(2015)
Cell-cycle quiescence maintains C. elegans germline stem cells independent of GLP-1/Notch
eLife 4:e10832.
https://doi.org/10.7554/eLife.10832

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https://doi.org/10.7554/eLife.10832

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