Bacterial contribution to genesis of the novel germ line determinant oskar

  1. Leo Blondel
  2. Tamsin E M Jones
  3. Cassandra G Extavour  Is a corresponding author
  1. Harvard University, United States
  2. European Bioinformatics Institute, United Kingdom


New cellular functions and developmental processes can evolve by modifying existing genes or creating novel genes. Novel genes can arise not only via duplication or mutation but also by acquiring foreign DNA, also called horizontal gene transfer (HGT). Here we show that HGT likely contributed to the creation of a novel gene indispensable for reproduction in some insects. Long considered a novel gene with unknown origin, oskar has evolved to fulfil a crucial role in insect germ cell formation. Our analysis of over 100 insect Oskar sequences suggests that Oskar arose de novo via fusion of eukaryotic and prokaryotic sequences. This work shows that highly unusual gene origin processes can give rise to novel genes that can facilitate evolution of novel developmental mechanisms.

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All data are available in the main text or the supplementary materials.

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Author details

  1. Leo Blondel

    Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2276-4821
  2. Tamsin E M Jones

    HGNC, European Bioinformatics Institute, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0027-0858
  3. Cassandra G Extavour

    Department of Organismic and Evolutionary Biology/Molecular and Cellular Biology, Harvard University, Cambridge, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2922-5855


Harvard University

  • Leo Blondel

Harvard University

  • Cassandra G Extavour

Harvard University

  • Tamsin E M Jones

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

Reviewing Editor

  1. Antonis Rokas, Vanderbilt University, United States

Publication history

  1. Received: January 29, 2019
  2. Accepted: February 23, 2020
  3. Accepted Manuscript published: February 24, 2020 (version 1)
  4. Version of Record published: May 26, 2020 (version 2)


© 2020, Blondel 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. Leo Blondel
  2. Tamsin E M Jones
  3. Cassandra G Extavour
Bacterial contribution to genesis of the novel germ line determinant oskar
eLife 9:e45539.
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