Genome streamlining in a minute herbivore that manipulates its host plant

Robert Greenhalgh, Wannes Dermauw, Joris J Glas, Stephane Rombauts, Nicky Wybouw, Jainy Thomas, Juan M Alba, Ellen J Pritham, Saioa Legarrea, René Feyereisen, Yves Van de Peer, Thomas Van Leeuwen (+2 others)
2020 eLife  
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
more » ... ements, 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.
doi:10.7554/elife.56689 pmid:33095158 pmcid:PMC7738191 fatcat:e5rrpxvdx5e7xmxseimhuhfuse