Expression characterization and functional analysis of juvenile hormone receptor gene CpMet in Culex pipiens pallens

doi:10.11853/j.issn.1003.8280.2021.06.005

Abstract

Abstract: Objective To investigate the expression characteristics of the juvenile hormone receptor gene CpMet of Culex pipiens pallens and its regulatory effects on reproduction. Methods Real-time quantitative PCR was used to determine the expression characteristics of the CpMet gene in different developmental stages of Cx. pipiens pallens, in different tissues of adult mosquitoes, and after hormone treatment. RNA interference technology was used to analyze the role of the CpMet gene in regulating the reproduction of female adult Cx. pipiens pallens. All data were expressed as the mean ±standard error of the mean and analyzed by SPSS 13.0 softwere. Results CpMet was expressed in all developmental stages of Cx. pipiens pallens. The expression level of CpMet was the highest in the egg stage, followed by the pupal and adult stages, and was very low in the larval stage. CpMet had a high expression level in the ovary of female adult mosquitoes, followed by the fat body. After treatment with the juvenile hormone analogue methoprene for 6 h, 12 h, and 24 h, the expression of CpMet was up-regulated by 1.27 times, 4.15 times, and 1.26 times in female adult mosquitoes, respectively, indicating that CpMet was positively regulated by juvenile hormone. After treating mosquito pupae with ecdysone 20E for 24 h, the expression of CpMet was increased sharply, indicating that 20E could induce CpMet gene expression. At 48 h after dsCpMet injection, the mRNA expression of CpMet was significantly decreased by 86.29%. In the egg masses produced by female mosquitoes with dsCpMet injection, the mean number of eggs dropped by 49.89%, and the hatching rate of eggs dropped to 73.36%. Conclusion Interfering with CpMet gene expression can significantly reduce the egg production of female Cx. pipiens pallens mosquitoes, indicating that CpMet can regulate the reproduction of Cx. pipiens pallens and can be used as a potential target for mosquito control.

Key words: Culex pipiens pallens, Met gene, Expression pattern, Functional analysis

摘要： 目的了解淡色库蚊保幼激素受体基因CpMet的表达特性以及生殖调控作用。方法采用荧光定量PCR法检测CpMet基因在淡色库蚊不同发育阶段、成虫不同组织及激素处理后的表达特性；利用RNA干扰技术解析CpMet基因在淡色库蚊雌成虫生殖调控中的作用。所有数据用平均值±标准误表示，采用SPSS 13.0软件进行统计学分析。结果 CpMet在淡色库蚊各个发育阶段均有表达，在卵期表达量显著高于其他阶段，其次是蛹期和成虫期，幼虫期表达量很低。CpMet在雌成蚊卵巢中表达水平较高，其次是脂肪体。进一步研究发现在保幼激素类似物烯虫酯处理6、12和24 h后，雌性成蚊的CpMet表达量分别上调1.27、4.15和1.26倍，表明CpMet受保幼激素的正调控。用蜕皮激素20E处理蚊蛹24 h后，CpMet基因的表达量急剧增加，表明CpMet基因表达受20E的诱导。注射dsCpMet 48 h后CpMet mRNA表达水平显著下调了86.29%；注射dsCpMet的雌蚊所产的卵块平均含卵数下降了49.89%，卵的孵化率降至73.36%。结论干扰CpMet基因表达能够显著降低雌蚊的产卵量，表明CpMet基因参与淡色库蚊生殖调控，可作为蚊虫控制的潜在靶标。

关键词: 淡色库蚊, Met基因, 表达模式, 功能分析

CLC Number:

R384.1
Q753

ZHOU Chang-yin, GUAN Qing-qing, DAI Yu-qi, LIU Hong-xia, QIAN Kun. Expression characterization and functional analysis of juvenile hormone receptor gene CpMet in Culex pipiens pallens[J]. Chinese Journal of Vector Biology and Control, 2021, 32(6): 680-685.

周长印, 关晴晴, 戴雨琪, 刘洪霞, 钱坤. 淡色库蚊保幼激素受体基因CpMet的表达特性和功能分析[J]. 中国媒介生物学及控制杂志, 2021, 32(6): 680-685.

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