Characterization of Arabidopsis Transcriptional Responses to Different Aphid Species Reveals Genes that Contribute to Host Susceptibility and Non-host Resistance

Abstract

Aphids are economically important pests that display exceptional variation in host range. The determinants of diverse aphid host ranges are not well understood, but it is likely that molecular interactions are involved. With significant progress being made towards understanding host responses upon aphid attack, the mechanisms underlying non-host resistance remain to be elucidated. Here, we investigated and compared Arabidopsis thaliana host and non-host responses to aphids at the transcriptional level using three different aphid species, Myzus persicae, Myzus cerasi and Rhopalosiphum pisum. Gene expression analyses revealed a high level of overlap in the overall gene expression changes during the host and non-host interactions with regards to the sets of genes differentially expressed and the direction of expression changes. Despite this overlap in transcriptional responses across interactions, there was a stronger repression of genes involved in metabolism and oxidative responses specifically during the host interaction with M. persicae. In addition, we identified a set of genes with opposite gene expression patterns during the host versus non-host interactions. Aphid performance assays on Arabidopsis mutants that were selected based on our transcriptome analyses identified novel genes contributing to host susceptibility, host defences during interactions with M. persicae as well to non-host resistance against R. padi. Understanding how plants respond to aphid species that differ in their ability to infest plant species, and identifying the genes and signaling pathways involved, is essential for the development of novel and durable aphid control in crop plants.

Pseudomonas syringae enhances herbivory by suppressing the reactive oxygen burst in Arabidopsis

“…30% more leaf tissue on the cell wall peroxidase-deficient anti-sense transgenic line asFBP1.1 (Bindschedler et al, 2006; Daudi et al 2012), which suggests that cell wall peroxidases are a major source of ROS during herbivore attack as they are during pathogen attack. Although the NADPH oxidases also produce ROS during herbivore and pathogen attack, and contribute to plant defense against aphids (Jaouannet et al, 2015; Miller et al, 2009; Torres et al, 2002, 2005), and caterpillars (Wu et al, 2013), S. flava larvae consumed equal amounts of leaf tissue on the rbohD and rbohF mutants vs. WT plants (Figure 3C). In these latter mutants, any reduction in ROS-mediated resistance to S. flava might be offset by the enhanced propensity for initiating PCD as is the case in the pmr4-1 mutant.…”

Interplay of Plasma Membrane and Vacuolar Ion Channels, Together with BAK1, Elicits Rapid Cytosolic Calcium Elevations in Arabidopsis during Aphid Feeding

“…On the route to the phloem, the stylets navigate between epidermal and mesophyll cells, occasionally penetrating these cells during a process known as the pathway feeding phase (Tjallingii, 1985;Tjallingii and Esch, 1993). The ability of an aphid to feed successfully on a plant appears to be partly determined during these penetrations, as the pathway phase still occurs with aphid species unable to establish long-term feeding (Chen et al, 1997;Sauge et al, 1998;Jaouannet et al, 2015;Nam and Hardie, 2012). Furthermore, as with microbial pathogens, aphids are detected through a BAK1-dependent mechanism, although the PRRs involved have remained elusive, with FLAGELLIN-SENSITIVE2 (FLS2), EF-TU RECEPTOR (EFR), CHITIN ELICITOR RECEPTOR KINASE1 (CERK1), PEP1 RECEPTOR1 (PEPR1), and PEPR2 not appearing to play a role (Prince et al, 2014;Chaudhary et al, 2014).…”

Citrus leprosis virus C Infection Results in Hypersensitive-Like Response, Suppression of the JA/ET Plant Defense Pathway and Promotion of the Colonization of Its Mite Vector

“…Moreover, insects and mites secrete proteins in their saliva which modulate, and even suppress, the plant defense response (Kant et al, 2015; Villarroel et al, 2016). In the saliva, proteins from arthropod-associated microorganisms, i.e., endosymbiont bacteria and viruses, are also responsible for plant defense elicitation (Chaudhary et al, 2014; Jaouannet et al, 2015). Similarly, plant viruses encode suppressors to efficiently overcome the RNA silencing (Li and Ding, 2006).…”