1. Cell Biology
  2. Developmental Biology
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Bazooka/Par3 cooperates with Sanpodo for the assembly of Notch clusters following asymmetric division of Drosophila sensory organ precursor cells

  1. Elise Houssin
  2. Mathieu Pinot
  3. Karen Bellec
  4. Roland Le Borgne  Is a corresponding author
  1. CNRS, UMR 6290, France
  2. University of Glasgow, United Kingdom
Research Article
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Cite this article as: eLife 2021;10:e66659 doi: 10.7554/eLife.66659

Abstract

In multiple cell lineages, Delta-Notch signalling regulates cell fate decisions owing to unidirectional signalling between daughter cells. In Drosophila pupal sensory organ lineage, Notch regulates the intra-lineage pIIa/pIIb fate decision at cytokinesis. Notch and Delta that localise apically and basally at the pIIa-pIIb interface are expressed at low levels and their residence time at the plasma membrane is in the order of minutes. How Delta can effectively interact with Notch to trigger signalling from a large plasma membrane area remains poorly understood. Here, we report that the signalling interface possesses a unique apicobasal polarity with Par3/Bazooka localising in the form of nano-clusters at the apical and basal level. Notch is preferentially targeted to the pIIa-pIIb interface, where it co-clusters with Bazooka and its cofactor Sanpodo. Clusters whose assembly relies on Bazooka and Sanpodo activities are also positive for Neuralized, the E3 ligase required for Delta-activity. We propose that the nano-clusters act as snap buttons at the new pIIa-pIIb interface to allow efficient intra-lineage signalling.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files will be provided for each of the Figures

Article and author information

Author details

  1. Elise Houssin

    IGDR, CNRS, UMR 6290, Rennes, France
    Competing interests
    The authors declare that no competing interests exist.
  2. Mathieu Pinot

    IGDR, CNRS, UMR 6290, Rennes, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Karen Bellec

    Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5321-3921
  4. Roland Le Borgne

    IGDR, CNRS, UMR 6290, Rennes cedex, France
    For correspondence
    roland.leborgne@univ-rennes1.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6892-278X

Funding

Agence Nationale de la Recherche (ANR-16-CE13-004-01)

  • Roland Le Borgne

Ligue Contre le Cancer (Equipe Labellisée)

  • Roland Le Borgne

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

Reviewing Editor

  1. Elisabeth Knust, Max-Planck Institute of Molecular Cell Biology and Genetics, Germany

Publication history

  1. Received: January 18, 2021
  2. Preprint posted: January 19, 2021 (view preprint)
  3. Accepted: September 25, 2021
  4. Accepted Manuscript published: October 1, 2021 (version 1)
  5. Version of Record published: October 14, 2021 (version 2)

Copyright

© 2021, Houssin 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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