Drosophila S2 cells were transfected with the protein expression vector (pAC5.1 empty vector, LvMyD88, or LvMyD88-1), the reporter gene plasmid (pGL3-Basic, pGL3-AttA, pGL3-Drs, pGL3-Mtk, pGL3-PEN4, pGL3-PEN309, pGL3-PEN453, or pGL3-PEN536), and the pRL-TK Renilla luciferase plasmid (as an internal control: Promega, USA). After 48 h, the cells were harvested for measurement of luciferase activity using the dual-luciferase reporter assay system (Promega, USA). All data are representative of three independent experiments. The bars indicate the mean ± SD of the luciferase activity (n = 3). The statistical significance was calculated using Student's t-test (* indicates p<0.05 and ** indicates p<0.01compared with control).