Transcriptional Response of the Termite Coptotermes formosanus to Infection by the Entomopathogenic Fungus Akanthomyces lecanii
Coptotermes formosanus, a worldwide pest, inflicts large losses on agriculture, forestry, construction, and other industries. As efficient, environmentally friendly pest control methods, microbial biopesticides are widely used to manage major pests. We previously isolated an Akanthomyces lecanii strain with strong insecticidal activity against termites. However, the interaction between the biocontrol agent and termites is still unknown. In this study, PacBio single-molecule real-time (SMRT) sequencing technology and Illumina RNA-seq sequencing technology were used to explore the transcriptomic differences in C. formosanus before and after A. lecanii infection. A total of 7,882,407 full-length transcripts were obtained. Single genes were further annotated using the NR, GO, KEGG, COG/KOG, Swiss-Prot, and KEGG homology public databases. A total of 2,782 differentially expressed genes were identified, including 1,440 upregulated genes and 1,342 downregulated genes. The expression of the Toll signaling pathway, mitogen-activated protein kinase (MAPK) pathway, detoxification metabolism, and immune-related genes, including scavenger receptor, apolipophorin, Cdc42, Integrin, Toll, serine protease, and transferrin genes, may be related to A. lecanii infection. This work not only greatly enriches the gene annotation resources of C. formosanus but also provides a new perspective for understanding the fungal immune defense mechanisms of social insects at the molecular level. These findings provide a theoretical basis for the development of new immunosuppressive agents.