1. Developmental Biology
  2. Neuroscience
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Functional divergence of Plexin B structural motifs in distinct steps of Drosophila olfactory circuit assembly

  1. Ricardo Guajardo
  2. David J Luginbuhl
  3. Shuo Han
  4. Liqun Luo  Is a corresponding author
  5. Jiefu Li
  1. Howard Hughes Medical Institute, Stanford University, United States
  2. Stanford University, United States
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Cite this article as: eLife 2019;8:e48594 doi: 10.7554/eLife.48594

Abstract

Plexins exhibit multitudinous, evolutionarily conserved functions in neural development. How Plexins employ their diverse structural motifs in vivo to perform distinct roles is unclear. We previously reported that Plexin B (PlexB) controls multiple steps during the assembly of the Drosophila olfactory circuit (Li et al., 2018). Here, we systematically mutagenized structural motifs of PlexB and examined the function of these variants in these multiple steps: axon fasciculation, trajectory choice, and synaptic partner selection. We found that the extracellular Sema domain is essential for all three steps, the catalytic site of the intracellular RapGAP is engaged in none, and the intracellular GTPase-binding motifs are essential for trajectory choice and synaptic partner selection, but are dispensable for fasciculation. Moreover, extracellular PlexB cleavage serves as a regulatory mechanism of PlexB signaling. Thus, the divergent roles of PlexB motifs in distinct steps of neural development contribute to its functional versatility in neural circuit assembly.

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. Ricardo Guajardo

    Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. David J Luginbuhl

    Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Shuo Han

    Department of Chemistry, Stanford University, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Liqun Luo

    Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    For correspondence
    lluo@stanford.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5467-9264
  5. Jiefu Li

    Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0062-4652

Funding

Howard Hughes Medical Institute

  • Liqun Luo

National Institutes of Health (R01-DC005982)

  • Liqun Luo

The Yingwei Cui and Hui Zhao Neuroscience Fund

  • Liqun Luo

Stanford University (Bio-X Undergraduate Summer Research Program)

  • Ricardo Guajardo

Stanford University (Stanford Undergraduate Advising and Research Major Grant)

  • Ricardo Guajardo

Stanford University (Bio-X Bowes Interdisciplinary Graduate Fellowship)

  • Shuo Han

Genentech Foundation (Genentech Foundation Predoctoral Fellowship)

  • Jiefu Li

Stanford University (Vanessa Kong-Kerzner Graduate Fellowship)

  • Jiefu Li

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

Reviewing Editor

  1. Kristin Scott, University of California, Berkeley, United States

Publication history

  1. Received: May 22, 2019
  2. Accepted: June 20, 2019
  3. Accepted Manuscript published: June 21, 2019 (version 1)
  4. Version of Record published: June 27, 2019 (version 2)

Copyright

© 2019, Guajardo 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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