Fig. 1

CpCHSA gene expression patterns. Relative expression levels of CpCHSA in different stages and different tissues, as assessed using quantitative real-time PCR (qPCR). a Relative expression at different stages: egg (EG), larvae (L1–4), pupae (PU), adult post-eclosion (PE) and adult post-blood meal (PBM). Five mosquitoes were collected from each group for RNA extraction. Relative expression levels were calculated in comparison with that at 0 h EG, which was ascribed an arbitrary value of 1. b, c Relative expression level of CpCHSA in L4 (b) and adult mosquito at 72 h PE (c). Tissues included the head (HE), foregut (FG), midgut (MG), hindgut (HG), Malpighian tubules (MT), ovary (OV), leg (LE), wing (WI) and carcass (CA). Tissues from ten mosquitoes were collected from each group for RNA extraction. Relative expression levels were calculated in comparison with expression in MT (b) and HE (c), which were ascribed an arbitrary value of 1. The ACTB (β-actin) gene was used as an internal reference. Data are from three independent experiments with three biological replicates. Different lowercase letters above the bars indicate a statistically significant difference at P < 0.05 (analysis of variance [ANOVA]); the same letter indicates data are not significantly different. CpCHSA Chitin synthase A gene (CHSA) from Culex pipiens pallens. L1, L2, L3, L4 First-, second-, third-, fourth-instar larvae, respectively