Screening of immune-related genes against bacterial infection in Ostrinia furnacalis (Lepidoptera: Crambidae)

Abstract

Ostrinia furnacalis Guenée is an important pest of maize. The current use of microbial agents to control O. furnacalis have been relatively successful. However, upon infestation with microorganisms, O. furnacalis initiates an innate immune response to defend itself against foreign invaders. Therefore, understanding the immune mechanisms in O. furnacalis is important to ensure a more efficient use of microbial agents for the control of this pest. In the present study, a gram-positive bacterium, Staphylococcus aureus, and a gram-negative bacterium, Escherichia coli, were used to induce an immune response in O. furnacalis. Transcriptomic sequencing was then used to screen for genes that were significantly differentially expressed after microbial induction and sequence comparison and phylogenetic analysis to identify immune-related genes the expression of which was significantly induced. The results show a large number of genes were differentially expressed in O. furnacalis after microbial induction, the majority of which were immune-related genes. The expression of some immune-related genes such as those encoding antimicrobial peptides, peptidoglycan recognition proteins and serine protease inhibitors were strongly induced. Overall, our study increases the understanding of the mechanism of the innate immune response in O. furnacalis and provides a theoretical basis for better biological control using microbial agents.

Keywords

• transcriptomic sequencing
• immunity
• differentially expressed genes
• insect
• agricultural pest