The essential role of Dnmt1 in gametogenesis in the large milkweed bug Oncopeltus fasciatus
- University of Georgia, United States
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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The authors declare that there was no funding for this work.
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© 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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The essential role of Dnmt1 in gametogenesis in the large milkweed bug Oncopeltus fasciatus
eLife 10:e62202.
https://doi.org/10.7554/eLife.62202
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