Neuroblast-specific chromatin landscapes allows the integration of spatial and temporal cues during Drosophila neurogenesis

  1. Sonia Q Sen
  2. Sachin Chanchani
  3. Tony D Southall
  4. Chris Q Doe  Is a corresponding author
  1. Howard Hughes Medical Institute, University of Oregon, United States
  2. Imperial College London, United Kingdom

Abstract

Spatial and temporal cues are required to specify neuronal diversity, but how these cues are integrated in neural progenitors remains unknown. Drosophila progenitors (neuroblasts) are a good model: they are individually identifiable with relevant spatial and temporal transcription factors known. Here we test whether spatial/temporal factors act independently or sequentially in neuroblasts. We used Targeted-DamID to identify genomic binding sites of the Hunchback temporal factor in two neuroblasts (NB5-6 and NB7-4) that make different progeny. Hunchback targets were different in each neuroblast, ruling out the independent specification model. Moreover, each neuroblast had distinct open chromatin domains, which correlated with differential Hb-bound loci in each neuroblast. Importantly, Gsb/Pax3 spatial factor binding correlated with open chromatin in NB5-6, but not NB7-4. Our data support a model in which early-acting spatial factors establish neuroblast-specific open chromatin domains, leading to neuroblast-specific temporal factor binding and the production of different neurons in each neuroblast lineage.

Data availability

Data are available via the NCBI Gene Expression Omnibus database (accession number GSE123272).

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Sonia Q Sen

    Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Sachin Chanchani

    Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Tony D Southall

    Department of Life Sciences, Imperial College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8645-4198
  4. Chris Q Doe

    Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
    For correspondence
    cdoe@uoregon.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5980-8029

Funding

Howard Hughes Medical Institute

  • Chris Q Doe

National Institutes of Health (HD27056)

  • Chris Q Doe

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

Reviewing Editor

  1. Gail Mandel, Oregon Health and Science University, United States

Version history

  1. Received: November 30, 2018
  2. Accepted: January 24, 2019
  3. Accepted Manuscript published: January 29, 2019 (version 1)
  4. Version of Record published: February 15, 2019 (version 2)

Copyright

© 2019, Sen 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. Sonia Q Sen
  2. Sachin Chanchani
  3. Tony D Southall
  4. Chris Q Doe
(2019)
Neuroblast-specific chromatin landscapes allows the integration of spatial and temporal cues during Drosophila neurogenesis
eLife 8:e44036.
https://doi.org/10.7554/eLife.44036

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