Host-plant induced changes in microbial community structure and midgut gene expression in an invasive polyphage (Anoplophora glabripennis)

Abstract

Polyphagous insect herbivores possess diverse mechanisms to overcome challenges of feeding in multiple plant species including, but not limited to, transcriptional plasticity and associations with obligate or facultative symbionts. The Asian longhorned beetle (Anoplophora glabripennis) is a polyphagous wood-feeder capable of developing on over 100 tree species and, like other polyphages, its genome contains amplifications of digestive and detoxification genes. This insect also possesses a diverse gut microbial community, which has the metabolic potential to augment digestive physiology. While the genomic repertoires of A. glabripennis and its microbial community have been studied previously, comparatively less is known about how the gut transcriptome and community change in response to feeding in different hosts. In this study, we show that feeding in two suitable hosts (Acer spp. and Populus nigra) altered the expression levels of multicopy genes linked to digestion and detoxification. However, feeding in a host with documented resistance (Populus tomentosa) induced changes in the transcriptome and community beyond what was observed in insects reared in P. nigra, including the downregulation of numerous β-glucosidases, odorant binding proteins, and juvenile hormone binding proteins, the upregulation of several cuticular genes, and the loss of one major bacterial family from the gut community.

Mitochondrial DNA analysis reveals spatial genetic structure and high genetic diversity of Massicus raddei (Blessig) (Coleoptera: Cerambycidae) in China

“…However, few previous studies have reported that HAD phenomenon has been observed among wood-feeding longhorn beetles, but for A. glabripennis, another wood-boring pest, some experiments demonstrated that host trees can affect the insect's gut microbial community composition, the level of cellulase activity, and the expression level of digestive and detoxification genes (Erin et al, 2018;Geib et al, 2009). Therefore, it is presumed that similar effects are likely to occur among M. raddei larvae which live in various oak tree species, and that host plant-associated genomic differentiation will evolve over time.…”

Gut Bacteria Associated With Monochamus saltuarius (Coleoptera: Cerambycidae) and Their Possible Roles in Host Plant Adaptations

“…The diversity of gut bacteria in phytophagous insects is largely affected by the host plant. Different host plants result in different nutritional compositions and intestinal environments, which can significantly influence the insect's bacterial gut symbionts (Kim et al, 2017;Scully et al, 2018;Santos-Garcia et al, 2020). For example, bacterial symbionts associated with the guts of the western corn rootworm (Dematheis et al, 2012;Chu et al, 2013), the Colorado potato beetle (Chung et al, 2017;Wang et al, 2020), and Cephaloleia spp.…”

Comparative transcriptome analysis of the newly discovered insect vector of the pine wood nematode in China, revealing putative genes related to host plant adaptation

“…In order to examine genes related to host plant utilization, Mason et al [ 28 ] compared gene expression changes of the larvae of Anoplophora glabripennis feeding on a preferred host (the sugar maple) to those consuming a nutrient-rich artificial diet. Recently, Scully et al [ 29 ] examined how feeding on two susceptible ( Acer spp. and Populus nigra ) and a resistant host ( Populus tomentosa ) affected the gene expression of A. glabripennis .…”

“…Larvae of the Asian long-horned beetle Anoplophora glabripennis modulate a subset of genes associated with digestion when fed on a nutrient-poor, compared to a nutritious diet [ 28 ]. In addition, Scully et al [ 29 ] showed that feeding on two appropriate host plants ( Acer spp. and Populus nigra ) modified the expression levels of multicopy genes involved in digestion and detoxification in A. glabripennis .…”