Abstract: 【Aim】 To investigate whether carboxylesterase genes PaCarE1-4 of Pardosa astrigera are related to the metabolism of deltamethrin.【Methods】 The cDNA sequences of four carboxylesterase genes PaCarE1-4 of P. astrigera were cloned by RT-PCR, and their sequence characteristics were analyzed by bioinformatics software. The relative expression levels of the four carboxylesterase genes in different tissues (cephalothorax, abdomen, and leg) of female and male adults of P. astrigera and in male adults of P. astrigera after exposed to different concentrations (LC1₀=5.151 mg/L; LC₃₀=8.619 mg/L; and LC₅₀=12.311 mg/L) of deltamethrin for 12 h and LC₃₀ of deltamethrin for 2, 4, 8, 12, 24, and 48 h were assayed by RT-qPCR. 【Results】 The full-length cDNA sequences of carboxylesterase genes PaCarE1-4 (GenBank accession numbers: MZ643212, MZ643214, MZ643215 and MZ643216, respectively) were cloned. Their open reading frames (ORFs) are 1 653, 1 803, 1 827 and 1 818 bp, encoding 550, 600, 608 and 605 amino acids, respectively. Tissue expression profiles revealed that PaCarE1 and PaCarE2 were highly expressed in the abdomen of female and male adults of P. astrigera, with higher expression level in males than in females, while PaCarE3 and PaCarE4 were highly expressed in the cephalothorax of female and male adults of P. astrigera, with PaCarE3 showing higher expression level in females than in males and PaCarE4 showing higher expression level in males than in females. After treatment for 12 h, LC₃₀ of deltamethrin induced the expression of PaCarE1 in male adults of P. astrigera, while LC₁₀ and LC₃₀ of deltamethrin induced the expression of PaCarE2. In male adults of P. astrigera exposed to LC₃₀ of deltamethrin, the relative expression levels of PaCarE4 at various time points after treatment showed no significant difference from that in the control group (acetone treatment group), while the relative expression levels of PaCarE1 at 2, 8 and 12 h after treatment, PaCarE2 at 12 h after treatment and PaCarE3 at 24 h after treatment were significantly upregulated as compared to that in the control group. 【Conclusion】 The carboxylesterase genes PaCarE1, PaCarE2 and PaCarE3 can be induced by deltamethrin, indicating that they may participate in the metabolism of deltamethrin in P. astrigera. The results of this study are helpful for understanding the metabolism mechanism of foreign substances in P. astrigera, providing new ideas for the protection of this predatory enemy.

Key words: Pardosa astrigera, carboxylesterase, gene cloning, gene expression, detoxification metabolism