1. Cell Biology
  2. Stem Cells and Regenerative Medicine
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C. elegans GLP-1/Notch activates transcription in a probability gradient across the germline stem cell pool

  1. ChangHwan Lee
  2. Erika B Sorensen
  3. Tina R Lynch
  4. Judith Kimble  Is a corresponding author
  1. Howard Hughes Medical Institute, University of Wisconsin-Madison, United States
  2. Wabash College, United States
  3. University of Wisconsin-Madison, United States
Research Article
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Cite this article as: eLife 2016;5:e18370 doi: 10.7554/eLife.18370

Abstract

C. elegans Notch signaling maintains a pool of germline stem cells within their single-celled mesenchymal niche. Here we investigate the Notch transcriptional response in germline stem cells using single-molecule fluorescence in situ hybridization coupled with automated, high-throughput quantitation. This approach allows us to distinguish Notch-dependent nascent transcripts in the nucleus from mature mRNAs in the cytoplasm. We find that Notch-dependent active transcription sites occur in a probabilistic fashion and, unexpectedly, do so in a steep gradient across the stem cell pool. Yet these graded nuclear sites create a nearly uniform field of mRNAs that extends beyond the region of transcriptional activation. Therefore, active transcription sites provide a precise view of where the Notch-dependent transcriptional complex is productively engaged. Our findings offer a new window into the Notch transcriptional response and demonstrate the importance of assaying nascent transcripts at active transcription sites as a readout for canonical signaling.

Article and author information

Author details

  1. ChangHwan Lee

    Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Erika B Sorensen

    Department of Biology, Wabash College, Crawfordsville, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Tina R Lynch

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

    Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, United States
    For correspondence
    jekimble@wisc.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5622-2073

Funding

American Cancer Society (PF-14-147-01-DDC)

  • Erika B Sorensen

Howard Hughes Medical Institute

  • Judith Kimble

American Cancer Society (PF-14-147-01-DDC)

  • Erika B Sorensen

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

Reviewing Editor

  1. Janet Rossant, University of Toronto, Canada

Publication history

  1. Received: June 1, 2016
  2. Accepted: October 4, 2016
  3. Accepted Manuscript published: October 5, 2016 (version 1)
  4. Version of Record published: November 3, 2016 (version 2)
  5. Version of Record updated: August 10, 2017 (version 3)

Copyright

© 2016, Lee 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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