Abstract

Simple SummaryThe soybean aphid is an important pest of soybean, and its control still relies largely on chemical insecticides, which can lead to resistance and environmental concerns. A better understanding of the immune system of this insect may help identify new targets for sustainable pest management. In this study, we identified six genes related to the Janus kinase/signal transducer and activator of transcription signaling pathway, an immune communication system that helps insects respond to infection. Most of these genes were highly expressed in young aphids and were strongly activated after infection with two common bacteria,Escherichia coliandStaphylococcus aureus. When these genes were reduced using a gene-silencing method, aphid survival after bacterial infection decreased significantly. These results show that this pathway contributes to antibacterial defense in soybean aphids and may provide useful targets for future biologically based control strategies.The JAK/STAT pathway is a conserved signaling pathway involved in insect immune regulation. Although its antibacterial role has been investigated in some aphids, evidence is lacking forAphis glycines. In this study, we identified JAK/STAT pathway-related genes inA. glycinesand examined their roles in antibacterial defense. Candidate genes were identified and characterized through sequence, domain, and phylogenetic analyses. Developmental expression and transcriptional responses to bacterial infection were determined by qRT-PCR, and gene function was evaluated by RNA interference followed by bacterial challenge. Six putative JAK/STAT pathway-related genes were identified, includingAglyJak,AglyDome-1,AglyDome-2,AglyDome-3,AglyStat92E-1, andAglyStat92E-2. Conserved domain architecture and phylogenetic analysis confirmed these genes asA. glycinesJAK/STAT orthologs. Expression profiling showed that, except forAglyJakandAglyDome-2, most genes were most highly expressed in early nymphal stages, particularly i