Drosophila medulla neuroblast termination via apoptosis, differentiation and gliogenic switch is scheduled by the depletion of the neuroepithelial stem cell pool

  1. Phuong-Khanh Nguyen
  2. Louise Cheng  Is a corresponding author
  1. Peter MacCallum Cancer Centre, Australia

Abstract

The brain is consisted of diverse neurons arising from a limited number of neural stem cells. Drosophila neural stem cells called neuroblasts (NBs) produces specific neural lineages of various lineage sizes depending on their location in the brain. In the Drosophila visual processing centre - the optic lobes (OLs), medulla NBs derived from the neuroepithelium (NE) give rise to neurons and glia cells of the medulla cortex. The timing and the mechanisms responsible for the cessation of medulla NBs are so far not known. In this study, we show that the termination of medulla NBs during early pupal development is determined by the exhaustion of the NE stem cell pool. Hence, altering NE-NB transition during larval neurogenesis disrupts the timely termination of medulla NBs. Medulla NBs terminate neurogenesis via a combination of apoptosis, terminal symmetric division via Prospero, and a switch to gliogenesis via Glial Cell Missing (Gcm), however, these processes occur independently of each other. We also show that temporal progression of the medulla NBs is mostly not required for their termination. As the Drosophila OL shares a similar mode of division with mammalian neurogenesis, understanding when and how these progenitors cease proliferation during development can have important implications for mammalian brain size determination and regulation of its overall function.

Data availability

We have uploaded the source file into Dryad.Reviewer URL: https://datadryad.org/stash/share/QumPEgTjb-zIHLdL1mz061nXVyvdnnA89xfF-Ooxauo.doi:10.5061/dryad.tmpg4f56p

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Article and author information

Author details

  1. Phuong-Khanh Nguyen

    Peter MacCallum Cancer Centre, Parkville, Australia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8440-5360
  2. Louise Cheng

    Peter MacCallum Cancer Centre, Parkville, Australia
    For correspondence
    louise.cheng@petermac.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9712-4082

Funding

University of Melbourne (Graduate student scholarship)

  • Phuong-Khanh Nguyen

Peter MacCallum Foundation (Strategic Support for Research Leaders)

  • Louise Cheng

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

Reviewing Editor

  1. Yan Song, Peking University, China

Version history

  1. Received: February 22, 2024
  2. Accepted: June 20, 2024
  3. Accepted Manuscript published: June 21, 2024 (version 1)

Copyright

© 2024, Nguyen & Cheng

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. Phuong-Khanh Nguyen
  2. Louise Cheng
(2024)
Drosophila medulla neuroblast termination via apoptosis, differentiation and gliogenic switch is scheduled by the depletion of the neuroepithelial stem cell pool
eLife 13:e96876.
https://doi.org/10.7554/eLife.96876

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https://doi.org/10.7554/eLife.96876

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