Coordinated crosstalk between microtubules and actin by a spectraplakin regulates lumen formation and branching

  1. Delia Ricolo
  2. Sofia J Araujo  Is a corresponding author
  1. University of Barcelona, Spain


Subcellular lumen formation by single-cells involves complex cytoskeletal remodelling. We have previously shown that centrosomes are key players in the initiation of subcellular lumen formation in Drosophila melanogaster, but not much is known on the what leads to the growth of these subcellular luminal branches or makes them progress through a particular trajectory within the cytoplasm. Here, we have identified that the spectraplakin Short-stop (Shot) promotes the crosstalk between MTs and actin, which leads to the extension and guidance of the subcellular lumen within the Terminal Cell (TC) cytoplasm. Shot is enriched in cells undergoing the initial steps of subcellular branching as a direct response to FGF signalling. An excess of Shot induces ectopic acentrosomal luminal branching points in the embryonic and larval tracheal TC leading to cells with extra subcellular lumina. These data provide the first evidence for a role for spectraplakins in single-cell lumen formation and branching.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Delia Ricolo

    Genetics, Microbiology and Statisitics, University of Barcelona, Barcelona, Spain
    Competing interests
    The authors declare that no competing interests exist.
  2. Sofia J Araujo

    Genetics, Microbiology and Statistics, University of Barcelona, Barcelona, Spain
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4749-8913


Ministerio ciencia innovacion, Spain (PGC2018-099465-B-I00)

  • Delia Ricolo
  • Sofia J Araujo

Generalitat de Catalunya (2017 SGR 1455)

  • Delia Ricolo
  • Sofia J Araujo

Ministerio de Ciencia, Innovación y Universidades (FJCI201732443)

  • Delia Ricolo

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

Reviewing Editor

  1. Derek Applewhite, Reed College, United States

Publication history

  1. Received: July 15, 2020
  2. Accepted: October 27, 2020
  3. Accepted Manuscript published: October 28, 2020 (version 1)
  4. Version of Record published: November 12, 2020 (version 2)


© 2020, Ricolo & Araujo

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. Delia Ricolo
  2. Sofia J Araujo
Coordinated crosstalk between microtubules and actin by a spectraplakin regulates lumen formation and branching
eLife 9:e61111.

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