The essential role of Dnmt1 in gametogenesis in the large milkweed bug Oncopeltus fasciatus

Abstract

Given the importance of DNA methylation in protection of the genome against transposable elements and transcriptional regulation in other taxonomic groups, the diversity in both levels and patterns of DNA methylation in the insects raises questions about its function and evolution. We show that the maintenance DNA methyltransferase, DNMT1, affects meiosis and is essential to fertility in milkweed bugs, Oncopeltus fasciatus, while DNA methylation is not required in somatic cells. Our results support the hypothesis that Dnmt1 is required for the transition of germ cells to gametes in O. fasciatus and that this function is conserved in male and female gametogenesis. They further suggest that DNMT1 has a function independent of DNA methylation in germ cells. Our results raise the question of how a gene so critical in fitness across multiple insect species can have diverged widely across the insect tree of life.

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Source data files have been provided for Figures 2, 3, 4, and 6

Article and author information

Author details

  1. Joshua T Washington

    Entomology, University of Georgia, Athens, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Katelyn R Cavender

    Entomology, University of Georgia, Athens, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Ashley U Amukamara

    Entomology, University of Georgia, Athens, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Elizabeth C McKinney

    Entomology, University of Georgia, Athens, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Robert J Schmitz

    Department of Genetics, University of Georgia, Athens, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7538-6663
  6. Patricia J Moore

    Entomology, University of Georgia, Athens, United States
    For correspondence
    pjmoore@uga.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9802-7217

Funding

The authors declare that there was no funding for this work.

Reviewing Editor

  1. Detlef Weigel, Max Planck Institute for Developmental Biology, Germany

Version history

  1. Received: August 17, 2020
  2. Accepted: April 9, 2021
  3. Accepted Manuscript published: April 12, 2021 (version 1)
  4. Version of Record published: April 23, 2021 (version 2)

Copyright

© 2021, Washington 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. Joshua T Washington
  2. Katelyn R Cavender
  3. Ashley U Amukamara
  4. Elizabeth C McKinney
  5. Robert J Schmitz
  6. Patricia J Moore
(2021)
The essential role of Dnmt1 in gametogenesis in the large milkweed bug Oncopeltus fasciatus
eLife 10:e62202.
https://doi.org/10.7554/eLife.62202

Share this article

https://doi.org/10.7554/eLife.62202

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