Identification of the key genes involved in the regulation of symbiotic pathways induced by in peanut () roots.

We detected and compared the mRNA and protein expression levels of immunity-associated and symbiosis-associated genes in peanut () roots inoculated with entomopathogenic fungus or the phytopathogenic fungus , by RT-qPCR and parallel reaction monitoring (PRM). The selected genes were mainly associated with plant-fungus interactions, signal transduction, regulation of cell death, nitrogen or iron metabolism, nutrient acquisition or transport, and compound synthesis based on previous transcriptome analysis. The results showed that the host basal defense responses were significantly inhibited by both and , which suggests that both fungi actively suppress the host immunity for successful colonization and infection. However, only induced a strong host hypersensitivity, which indicates that the host is strongly resisting but potentially allowing Additionally, the genes (SYMRK, CaM, CCaMK, FRI2, ABCC2, F6H1, SCT, NRT24 and LTP1) related to symbiosis and growth were distinctively observed with an up-regulated expression following treatment, which implies that the host was actively initiating the establishment of symbiosis with the fungus. This study revealed a synergistic relationship between host immunosuppression and the promotion of symbiosis during interactions with . It suggested that benefited plant for symbiotic relationship, in addition to controlling herbivorous insects as an entomopathogen.