Data from: Adaptation of a polyphagous herbivore to a novel host plant extensively shapes the transcriptome of herbivore and host

Generalist arthropod herbivores rapidly adapt to a broad range of host
plants. However, the extent of transcriptional reprogramming in the
herbivore and its hosts associated with adaptation remains poorly
understood. Using the spider mite Tetranychus urticae and tomato as models
with available genomic resources, we investigated the reciprocal
genomewide transcriptional changes in both spider mite and tomato as a
consequence of mite's adaptation to tomato. We transferred a
genetically diverse mite population from bean to tomato where triplicated
populations were allowed to propagate for 30 generations. Evolving
populations greatly increased their reproductive performance on tomato
relative to their progenitors when reared under identical conditions,
indicative of genetic adaptation. Analysis of transcriptional changes
associated with mite adaptation to tomato revealed two main components.
First, adaptation resulted in a set of mite genes that were constitutively
downregulated, independently of the host. These genes were mostly of an
unknown function. Second, adapted mites mounted an altered transcriptional
response that had greater amplitude of changes when re-exposed to tomato,
relative to nonadapted mites. This gene set was enriched in genes encoding
detoxifying enzymes and xenobiotic transporters. Besides the direct
effects on mite gene expression, adaptation also indirectly affected the
tomato transcriptional responses, which were attenuated upon feeding of
adapted mites, relative to the induced responses by nonadapted mite
feeding. Thus, constitutive downregulation and increased transcriptional
plasticity of genes in a herbivore may play a central role in adaptation
to host plants, leading to both a higher detoxification potential and
reduced production of plant defence compounds.