Abstract

Cephalopods are set apart from other mollusks by their advanced behavioral abilities and by the complexity of their nervous systems. Because of the great evolutionary distance that separates vertebrates from cephalopods, it is evident that higher cognitive features have evolved separately in these clades despite the similarities that they share. Alongside their complex behavioral abilities, cephalopods have evolved specialized cells and tissues, such as the chromatophores for camouflage or suckers to grasp prey. Despite significant progress in genome and transcriptome sequencing, the molecular identities of cell types in cephalopods remain largely unknown. We here combine single-cell transcriptomics with in situ gene expression analysis to uncover cell type diversity in the European squid Loligo vulgaris. We describe cell types that are conserved with other phyla such as neurons, muscles, or connective tissues but also cephalopod-specific cells, such as chromatophores or sucker cells. Moreover, we investigate major components of the squid nervous system including progenitor and developing cells, differentiated cells of the brain and optic lobes as well as sensory systems of the head. Our study provides a molecular assessment for conserved and novel cell types in cephalopods and a framework for mapping the nervous system of L. vulgaris.

Data availability

Sequencing data have been deposited in GEO under accession code GSE200108

The following data sets were generated

Article and author information

Author details

  1. Jules Duruz

    Department of Biology, Universität Fribourg, Fribourg, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  2. Marta Sprecher

    Department of Biology, Universität Fribourg, Fribourg, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  3. Jenifer C Kaldun

    Department of Biology, Universität Fribourg, Fribourg, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Al-Sayed Al-Soudy

    Department of Biology, Universität Fribourg, Fribourg, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7830-9660
  5. Heidi EL Lischer

    Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9616-2092
  6. Geert van Geest

    Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1561-078X
  7. Pamela Nicholson

    Institute of genetics, University of Bern, Bern, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  8. Rémy Bruggmann

    Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4733-7922
  9. Simon G Sprecher

    1Department of Biology, Universität Fribourg, Fribourg, Switzerland
    For correspondence
    simon.sprecher@unifr.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9060-3750

Funding

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (310030_188471)

  • Simon G Sprecher

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (IZCOZ0_182957)

  • Simon G Sprecher

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

Copyright

© 2023, Duruz 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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  1. Jules Duruz
  2. Marta Sprecher
  3. Jenifer C Kaldun
  4. Al-Sayed Al-Soudy
  5. Heidi EL Lischer
  6. Geert van Geest
  7. Pamela Nicholson
  8. Rémy Bruggmann
  9. Simon G Sprecher
(2023)
Molecular characterization of cell types in the squid Loligo vulgaris
eLife 12:e80670.
https://doi.org/10.7554/eLife.80670

Share this article

https://doi.org/10.7554/eLife.80670

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