Co-expression of xenopsin and rhabdomeric opsin in photoreceptors bearing microvilli and cilia

  1. Oliver Vöcking  Is a corresponding author
  2. Ioannis Kourtesis
  3. Sharat Chandra Tumu
  4. Harald Hausen  Is a corresponding author
  1. University of Bergen, Norway

Abstract

Ciliary and rhabdomeric opsins are employed by cells differing fundamentally in structure and molecular physiology, such as ciliary vertebrate rods and cones and protostome microvillar eye photoreceptors. We report unprecedented cellular co-expression of rhabdomeric opsin and a visual pigment of the recently described xenopsins in larval eyes of a mollusk. The photoreceptors bear both microvilli and cilia and express orthologs to transporters for microvillar and ciliary opsin trafficking. Highly conserved but distinct gene structures suggest that xenopsins and ciliary opsins are of independent origin, irrespective of their mutually exclusive distribution in animals.Furthermore, we propose that frequent opsin gene loss had big influence on evolution, organization and function of brain and eye photoreceptor cells in bilaterian animals. Presence of xenopsin in eyes of even different design might be due to common origin and initial employment in a highly plastic photoreceptor cell type of mixed microvillar/ciliary organization.

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Article and author information

Author details

  1. Oliver Vöcking

    Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
    For correspondence
    voecking@pitt.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Ioannis Kourtesis

    Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
    Competing interests
    The authors declare that no competing interests exist.
  3. Sharat Chandra Tumu

    Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
    Competing interests
    The authors declare that no competing interests exist.
  4. Harald Hausen

    Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
    For correspondence
    harald.hausen@uib.no
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2788-2835

Funding

Universitetet i Bergen

  • Harald Hausen

Norges Forskningsråd

  • Harald Hausen

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

Reviewing Editor

  1. Russ Fernald, Stanford University, United States

Publication history

  1. Received: November 22, 2016
  2. Accepted: September 1, 2017
  3. Accepted Manuscript published: September 6, 2017 (version 1)
  4. Version of Record published: October 19, 2017 (version 2)

Copyright

© 2017, Vöcking 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. Oliver Vöcking
  2. Ioannis Kourtesis
  3. Sharat Chandra Tumu
  4. Harald Hausen
(2017)
Co-expression of xenopsin and rhabdomeric opsin in photoreceptors bearing microvilli and cilia
eLife 6:e23435.
https://doi.org/10.7554/eLife.23435
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