Mutations associated with human neural tube defects display disrupted planar cell polarity in Drosophila

  1. Ashley C Humphries
  2. Sonali Narang
  3. Marek Mlodzik  Is a corresponding author
  1. Icahn Medical School - Mount Sinai Hospital, United States
  2. NYU School of Medicine, United States

Abstract

Planar cell polarity (PCP) and neural tube defects (NTDs) are linked, with a subset of NTD patients found to harbour mutations in PCP genes, but there is limited data on whether these mutations disrupt PCP signaling in vivo. The core PCP gene Van Gogh (Vang), Vangl1/2 in mammals, is the most specific for PCP. We thus addressed potential causality of NTD-associated Vangl1/2 mutations, from either mouse or human patients, in Drosophila allowing intricate analysis of the PCP pathway. Introducing the respective mammalian mutations into Drosophila Vang revealed defective phenotypic and functional behaviors, with changes to Vang localization, post-translational modification, and mechanistic function, such as its ability to interact with PCP effectors. Our findings provide mechanistic insight into how different mammalian mutations contribute to developmental disorders and strengthen the link between PCP and NTD. Importantly, analyses of the human mutations revealed that each is a causative factor for the associated NTD.

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 Figures 1, 2 and 5.

Article and author information

Author details

  1. Ashley C Humphries

    Cell, Developmental, and Regenerative Biology, Icahn Medical School - Mount Sinai Hospital, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Sonali Narang

    Pathology, NYU School of Medicine, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Marek Mlodzik

    Cell, Developmental, and Regenerative Biology, Icahn Medical School - Mount Sinai Hospital, New York, United States
    For correspondence
    marek.mlodzik@mssm.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0628-3465

Funding

National Institute of General Medical Sciences (R35 GM127103)

  • Marek Mlodzik

National Eye Institute (R01 EY013256)

  • Marek Mlodzik

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

Reviewing Editor

  1. Hugo J Bellen, Baylor College of Medicine, United States

Version history

  1. Received: November 12, 2019
  2. Accepted: March 31, 2020
  3. Accepted Manuscript published: April 1, 2020 (version 1)
  4. Version of Record published: April 23, 2020 (version 2)

Copyright

© 2020, Humphries 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

  • 2,296
    Page views
  • 336
    Downloads
  • 13
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

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. Ashley C Humphries
  2. Sonali Narang
  3. Marek Mlodzik
(2020)
Mutations associated with human neural tube defects display disrupted planar cell polarity in Drosophila
eLife 9:e53532.
https://doi.org/10.7554/eLife.53532

Further reading

    1. Chromosomes and Gene Expression
    2. Developmental Biology
    Virginia L Pimmett, Mounia Lagha
    Insight

    Imaging experiments reveal the complex and dynamic nature of the transcriptional hubs associated with Notch signaling.

    1. Cell Biology
    2. Developmental Biology
    Simon Schneider, Andjela Kovacevic ... Hubert Schorle
    Research Article

    Cylicins are testis-specific proteins, which are exclusively expressed during spermiogenesis. In mice and humans, two Cylicins, the gonosomal X-linked Cylicin 1 (Cylc1/CYLC1) and the autosomal Cylicin 2 (Cylc2/CYLC2) genes, have been identified. Cylicins are cytoskeletal proteins with an overall positive charge due to lysine-rich repeats. While Cylicins have been localized in the acrosomal region of round spermatids, they resemble a major component of the calyx within the perinuclear theca at the posterior part of mature sperm nuclei. However, the role of Cylicins during spermiogenesis has not yet been investigated. Here, we applied CRISPR/Cas9-mediated gene editing in zygotes to establish Cylc1- and Cylc2-deficient mouse lines as a model to study the function of these proteins. Cylc1 deficiency resulted in male subfertility, whereas Cylc2-/-, Cylc1-/yCylc2+/-, and Cylc1-/yCylc2-/- males were infertile. Phenotypical characterization revealed that loss of Cylicins prevents proper calyx assembly during spermiogenesis. This results in decreased epididymal sperm counts, impaired shedding of excess cytoplasm, and severe structural malformations, ultimately resulting in impaired sperm motility. Furthermore, exome sequencing identified an infertile man with a hemizygous variant in CYLC1 and a heterozygous variant in CYLC2, displaying morphological abnormalities of the sperm including the absence of the acrosome. Thus, our study highlights the relevance and importance of Cylicins for spermiogenic remodeling and male fertility in human and mouse, and provides the basis for further studies on unraveling the complex molecular interactions between perinuclear theca proteins required during spermiogenesis.