The tomato russet mite, Aculops lycopersici, is among the smallest animals on earth. It is a worldwide pest on tomato and can potently suppress the host's natural resistance. We sequenced its genome, the first of an eriophyoid, and explored whether there are genomic features associated with the mite's minute size and lifestyle. At only 32.5 Mb, the genome is the smallest yet reported for any arthropod and, reminiscent of microbial eukaryotes, exceptionally streamlined. It has few transposable elements, tiny intergenic regions, and is remarkably intron-poor, as more than 80% of coding genes are intronless. Furthermore, in accordance with ecological specialization theory, this defense-suppressing herbivore has extremely reduced environmental response gene families such as those involved in chemoreception and detoxification. Other losses associate with this species' highly derived body plan. Our findings accelerate the understanding of evolutionary forces underpinning metazoan life at the limits of small physical and genome size.
- Merijn R Kant
- Richard M Clark
- Thomas Van Leeuwen
- Wannes Dermauw
- Robert Greenhalgh
- Nicky Wybouw
- Thomas Van Leeuwen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Detlef Weigel, Max Planck Institute for Developmental Biology, Germany
- Received: March 5, 2020
- Accepted: October 22, 2020
- Accepted Manuscript published: October 23, 2020 (version 1)
© 2020, Greenhalgh 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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