昆虫学报 ›› 2022, Vol. 65 ›› Issue (12): 1636-1644.doi: 10.16380/j.kcxb.2022.12.009

• 研究论文 • 上一篇    下一篇

MicroRNA通路中的关键因子Dicer-1和Argonaute-1对豌豆蚜免疫防御的影响

许珍珍, 蒋新怡, 石苏可, 吕志强*   

  1. (西北农林科技大学植物保护学院, 陕西杨凌 712100)
  • 出版日期:2022-12-20 发布日期:2023-01-19

Effects of key factors Dicer-1 and Argonaute-1 in microRNA pathway on the immunity defense in the pea aphid, Acyrthosiphon pisum(Hemiptera: Aphididae)

XU Zhen-Zhen, JIANG Xin-Yi, SHI Su-Ke, LÜ Zhi-Qiang*   

  1. (College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China)
  • Online:2022-12-20 Published:2023-01-19

摘要: 【目的】研究microRNA(miRNA)通路中两个关键组分Dicer-1和Argonaute-1(Ago-1)在豌豆蚜Acyrthosiphon pisum抵御细菌和真菌侵染中的作用,加深对豌豆蚜免疫防御系统的了解。【方法】用qRT-PCR检测细菌金黄色葡萄球菌Staphylococcus aureus和大肠杆菌Escherichia coli以及真菌球孢白僵菌Beauveria bassiana分别侵染后豌豆蚜成蚜体内Dicer-1和Ago-1的表达量;通过注射法利用RNAi技术对豌豆蚜成蚜Dicer-1和Ago-1进行沉默后,感染金黄色葡萄球菌、大肠杆菌和球孢白僵菌,检测豌豆蚜体内细菌和真菌的增殖和统计豌豆蚜成蚜存活率。【结果】与0.85% NaCl溶液处理的对照组相比,金黄色葡萄球菌、大肠杆菌和球孢白僵菌侵染豌豆蚜成蚜后,其体内Dicer-1和Ago-1的表达量发生了一定程度的上调。RNAi干扰Dicer-1后,感染金黄色葡萄球菌36 h时豌豆蚜成蚜中细菌菌落数显著高于对照组(注射dsLTA)的,但感染后7 d时的存活率与对照组无显著差异;感染大肠杆菌12和24 h时豌豆蚜成蚜体内的细菌菌落数均显著高于对照组的,但感染后7 d时的存活率显著低于对照组的;感染球孢白僵菌后6 d,豌豆蚜成蚜体内真菌孢子数显著高于对照组的,但感染后7 d时的存活率显著低于对照组的。RNAi敲降Ago-1后感染金黄色葡萄球菌,豌豆蚜成蚜体内细菌菌落数在36 h时显著高于对照组的,但感染后7 d时的存活率显著低于对照组的;感染大肠杆菌后,在24 h时豌豆蚜成蚜体内细菌菌落数显著高于对照组的,感染后7 d时的存活率略低于对照组的,但无显著差异;感染球孢白僵菌后6 d,豌豆蚜成蚜体内真菌孢子数显著高于对照组的,但感染后7 d时的存活率显著低于对照组的。【结论】豌豆蚜miRNA通路中的两个关键组分Dicer-1和Ago-1参与了豌豆蚜抵御细菌和真菌侵染的免疫防御反应,尤其在抵御真菌的防御反应中有重要作用。

关键词: 豌豆蚜, miRNA通路, Dicer-1, Argonaute-1, RNA干扰

Abstract: 【Aim】 To study the function of two key components Dicer-1 and Argonaute-1 (Ago-1) of microRNA (miRNA) pathway in Acyrthosiphon pisum in defense against bacteria and fungi and to strengthen the knowledge of A. pisum immune system. 【Methods】 qRT-PCR was used to detect the expression levels of Dicer-1 and Ago-1 in A. pisum adults infected with the bacteria Staphylococcus aureus andEscherichiacoli, andthefungusBeauveriabassiana, respectively. After Dicer-1 and Ago-1 of A. pisum adults were silenced by RNAi through injection method followed by infection of S. aureus, E. coli and B. bassiana, the proliferation of the bacteria and the fungus and the survival rate of A. pisum adults were examined. 【Results】 The expression levels of Dicer-1 and Ago-1 in A. pisum adults injected by S. aureus, E. coli and B. bassiana were up-regulated as compared to those in the control group (treated with 0.85% NaCl solution). After RNAi of Dicer-1, the colony-forming unit (CFU) in A. pisum adults at 36 h post infection with S. aureus significantly increased as compared to that in the control group (injected with dsLTA), but there was no significant difference in the survival rate at 7 d after infection between the Dicer-1-silenced group and the control group. After RNAi of Dicer-1, the CFUs in A. pisum adults at 12 and 24 h post infection of E. coli significantly increased, but the survival rate at 7 d post infection significantly decreased, as compared with those in the control group. At 6 d after infection of B. bassiana, the fungal spores in the Dicer-1silenced group significantly increased, but their survival rate at 7 d post infection significantly decreased, as compared with those in the control group. When Ago-1 was knocked down by RNAi, the CFUs in A. pisum adults at 36 h after infection by S. aureus and 24 h after infection by E. coli were significantly higher than those in the control group, respectively, and the survival rate of A. pisum adults infected by S. aureus at 7 d post infection decreased significantly as compared with that in the control group, while the survival rate of adults at 7 d post infection by E. coli had no significant change. At 6 d after infection with B. bassiana, the Ago-1-silenced A. pisum adults bore a significantly larger amount of fungal spores than the control group, but had significantly decreased survival rate at 7 d post infection as compared with the control group. 【Conclusion】 Two crucial elements Dicer-1 and Ago-1 in mRNA pathway are involved in the immune defense of A. pisum against bacteria and fungi, particularly against bacteria.

Key words: Acyrthosiphon pisum, miRNA pathway, Dice-1, Argonaute-1, RNA interference