Fig. 4

Expression profile of HSP genes in three pyrethroid-resistant populations compared to pyrethroid-susceptible strain (WX-LS) Anopheles sinensis, detected by RNA-seq. The three resistant populations are Anhui (AH-FR, marked in blue), Chongqing (CQ-FR, red) and Yunnan (YN-FR, green), respectively. Genes with FPKM value ≥ 2 and p-value < 0.05 are considered to be significantly upregulated, whereas those with FPKM value < 0.5 and p-value < 0.05 are regarded as significantly downregulated. Vertical dotted lines illustrate the 1 (FPKM = 2) and − 1 (FPKM = 0.5) of Log2 (fold changes of FPKM value) values on the X-axis, and horizontal dotted lines denote the p-value = 0.05 of − Log10 (p-value) on the Y-axis. AsHSP90AB is significantly upregulated in all three resistant populations, AsHSP70-2 is significantly upregulated in both AH-FR and CQ-FR and AsHSP21.7 and AsDNAJB4 are significantly upregulated only in YN-FR