Sticks and stones, a conserved cell surface ligand for the Type IIa RPTP Lar, regulates neural circuit wiring in Drosophila

  1. Namrata Bali  Is a corresponding author
  2. Hyung-Kook (Peter) Lee
  3. Kai Zinn  Is a corresponding author
  1. California Institute of Technology, United States

Abstract

Type IIa receptor-like protein tyrosine phosphatases (RPTPs) are essential for neural development. They have cell adhesion molecule (CAM)-like extracellular domains that interact with cell-surface ligands and coreceptors. We identified the immunoglobulin superfamily CAM Sticks and Stones (Sns) as a new partner for the Drosophila Type IIa RPTP Lar. Lar and Sns bind to each other in embryos and in vitro, and the human Sns ortholog, Nephrin, binds to human Type IIa RPTPs. Genetic analysis shows that Lar and Sns function together to regulate larval neuromuscular junction development, axon guidance in the mushroom body (MB), and innervation of the optic lobe medulla by R7 photoreceptors. In the neuromuscular system, Lar and Sns are both required in motor neurons, and may function as coreceptors. In the MB and OL, however, the relevant Lar-Sns interactions are in trans (between neurons), so Sns functions as a Lar ligand in these systems.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files; Source Data files have been provided for Figure 4, Figure 4 - figure supplement 1 and 2, Figure 6 and Figure 6 - Figure supplement 1.

Article and author information

Author details

  1. Namrata Bali

    Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
    For correspondence
    nbali@caltech.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7219-5439
  2. Hyung-Kook (Peter) Lee

    Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Kai Zinn

    Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
    For correspondence
    zinnk@caltech.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6706-5605

Funding

National Institutes of Health (R37 NS028182)

  • Kai Zinn

National Institutes of Health (RO1 NS096509)

  • Kai Zinn

California Institute of Technology (Gordon Ross Postdoctoral Fellowship)

  • Namrata Bali

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

Copyright

© 2022, Bali 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.

Metrics

  • 1,044
    views
  • 230
    downloads
  • 9
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Namrata Bali
  2. Hyung-Kook (Peter) Lee
  3. Kai Zinn
(2022)
Sticks and stones, a conserved cell surface ligand for the Type IIa RPTP Lar, regulates neural circuit wiring in Drosophila
eLife 11:e71469.
https://doi.org/10.7554/eLife.71469

Share this article

https://doi.org/10.7554/eLife.71469

Further reading

    1. Developmental Biology
    Satoshi Yamashita, Shuji Ishihara, François Graner
    Research Article

    Apical constriction is a basic mechanism for epithelial morphogenesis, making columnar cells into wedge shape and bending a flat cell sheet. It has long been thought that an apically localized myosin generates a contractile force and drives the cell deformation. However, when we tested the increased apical surface contractility in a cellular Potts model simulation, the constriction increased pressure inside the cell and pushed its lateral surface outward, making the cells adopt a drop shape instead of the expected wedge shape. To keep the lateral surface straight, we considered an alternative model in which the cell shape was determined by cell membrane elasticity and endocytosis, and the increased pressure is balanced among the cells. The cellular Potts model simulation succeeded in reproducing the apical constriction, and it also suggested that a too strong apical surface tension might prevent the tissue invagination.

    1. Cancer Biology
    2. Developmental Biology
    Sara Jaber, Eliana Eldawra ... Franck Toledo
    Research Article

    Missense ‘hotspot’ mutations localized in six p53 codons account for 20% of TP53 mutations in human cancers. Hotspot p53 mutants have lost the tumor suppressive functions of the wildtype protein, but whether and how they may gain additional functions promoting tumorigenesis remain controversial. Here, we generated Trp53Y217C, a mouse model of the human hotspot mutant TP53Y220C. DNA damage responses were lost in Trp53Y217C/Y217C (Trp53YC/YC) cells, and Trp53YC/YC fibroblasts exhibited increased chromosome instability compared to Trp53-/- cells. Furthermore, Trp53YC/YC male mice died earlier than Trp53-/- males, with more aggressive thymic lymphomas. This correlated with an increased expression of inflammation-related genes in Trp53YC/YC thymic cells compared to Trp53-/- cells. Surprisingly, we recovered only one Trp53YC/YC female for 22 Trp53YC/YC males at weaning, a skewed distribution explained by a high frequency of Trp53YC/YC female embryos with exencephaly and the death of most Trp53YC/YC female neonates. Strikingly, however, when we treated pregnant females with the anti-inflammatory drug supformin (LCC-12), we observed a fivefold increase in the proportion of viable Trp53YC/YC weaned females in their progeny. Together, these data suggest that the p53Y217C mutation not only abrogates wildtype p53 functions but also promotes inflammation, with oncogenic effects in males and teratogenic effects in females.