Regulation of Antimicrobial Peptides in Aag2 Cells.

Antimicrobial peptides (AMPs) are an important group of immune effectors that play a role in combating microbial infections in invertebrates. Most of the current information on the regulation of insect AMPs in microbial infection have been gained from , and their regulation in other insects are still not completely understood. Here, we generated an AMP induction profile in response to infections with some Gram-negative, -positive bacteria, and fungi in embryonic Aag2 cells. Most of the AMP inductions caused by the gram-negative bacteria was controlled by the Immune deficiency (Imd) pathway; nonetheless, , an gene discovered only in mosquitoes, was combinatorially regulated by the Imd, Toll and JAK-STAT pathways in the Aag2 cells. promoter analyses including specific sequence motif deletions implicated these three pathways in activity, as shown by a luciferase assay. Moreover, the recognition between Rel1 (refer to Dif/Dorsal in ) and STAT and their regulatory sites at the promoter site was validated by a super-shift electrophoretic mobility shift assay (EMSA). Our study provides information that increases our understanding of the regulation of s in response to microbial infections in mosquitoes. And it is a new finding that the AMPs are mainly regulated Imd pathway only, which is quite different from the previous understanding obtained from Drosophila.