中国农业科学 ›› 2015, Vol. 48 ›› Issue (19): 3857-3865.doi: 10.3864/j.issn.0578-1752.2015.19.008

• 植物保护 • 上一篇    下一篇

橘小实蝇幼虫解毒酶系基因应对高效氯氰菊酯胁迫的组织特异性表达

申光茂1,王晓娜2,黄勇1,豆威1,王进军1   

  1. 1西南大学植物保护学院/昆虫学及害虫控制工程重庆市市级重点实验室,重庆 400715
    2重庆市花卉园管理处,重庆 401147
  • 收稿日期:2015-04-17 出版日期:2015-10-01 发布日期:2015-10-01
  • 通讯作者: 王进军,Tel:023-68250255;E-mail:jjwang7008@yahoo.com
  • 作者简介:申光茂,Tel:023-68250653;E-mail:blackaet@163.com
  • 基金资助:
    国家公益性行业(农业)科研专项(201203038)、现代柑橘产业技术体系岗位科学家经费(CARS-27)、中央高校基本科研业务费团队项目(2362014XK08)

Tissue Specific Expression of Genes Encoding Detoxification Enzymes in the Larvae of Bactrocera dorsalis Under β-Cypermethrin Stress

SHEN Guang-mao1, WANG Xiao-na2, HUANG Yong1, DOU Wei1, WANG Jin-jun1   

  1. 1College of Plant Protection, Southwest University/Key Laboratory of Entomology and Pest Control Engineering, Chongqing 400715
    2Flower Garden Management Office of Chongqing, Chongqing 401147
  • Received:2015-04-17 Online:2015-10-01 Published:2015-10-01

摘要: 【目的】基于橘小实蝇(Bactrocera dorsalis)转录组数据,系统分析橘小实蝇幼虫解毒代谢酶系基因在受到高效氯氰菊酯持续胁迫时的表达模式,鉴定其中起主要作用的基因,并探讨这些基因组织差异表达的生物学意义。【方法】利用qPCR技术检测橘小实蝇幼虫受到高效氯氰菊酯持续胁迫后,30个解毒代谢酶系(GSTs、P450s、CCEs)基因在整虫、中肠以及脂肪体的表达水平变化情况。【结果】在高效氯氰菊酯持续胁迫作用下,橘小实蝇8个GSTs基因中,其mRNA表达量出现明显上调的主要是Delta家族的4个基因,它们在中肠和脂肪体均出现了5.6—32.5倍的过量表达,而其他家族的GSTs基因经高效氯氰菊酯胁迫后没有出现明显的应激反应。同时,Delta家族的GSTs基因虽然在中肠和脂肪体对药剂胁迫有积极的响应,但是它们的表达在整虫却没有明显的变化。6个CCEs基因在整虫中出现一定程度的上调,其中α-E3基因的表达量上调了4.1倍,但是这些基因在中肠和脂肪体均没有出现上调的情况。16个P450s基因的定量分析结果表明,有多个P450s基因的mRNA的表达出现了上调,且大部分基因属于CYP4和CYP6两个家族。其中,CYP4家族中出现明显上调反应的主要有CYP4D47(中肠)、CYP4E9(整虫、脂肪体)和CYP4P5(整虫、脂肪体)。CYP4AD1的表达量在中肠和脂肪体均有一定程度的上调,而在整虫中没有变化。另外,CYP4S18CYP4AC4没有出现应激表达或者表达量的变化不明显。CYP6家族中,CYP6A48CYP6A41在脂肪体的表达量显著上调,分别提高了18.0和9.6倍,CYP6G6CYP6A50在脂肪体的表达量也有一定程度的上升,而CYP6EK1的表达量虽然在整虫提高了4.8倍,但是在中肠和脂肪体并没有明显的变化。其他家族的P450s基因,如CYP12C2CYP9F6CYP12N1CYP309B1等基因的表达量经高效氯氰菊酯胁迫后在脂肪体中也出现了显著的上调,而CYP317B1的表达量在药剂压力下并没有明显的变化。【结论】橘小实蝇幼虫在应对高效氯氰菊酯胁迫时,体内的解毒代谢酶系基因集中在中肠和脂肪体高水平表达,但存在整体保持平衡的现象,推测橘小实蝇在应对杀虫剂的持续胁迫时,存在趋于平衡的能量分配策略,即通过提高能量的利用效率,减少在抵御外源杀虫剂伤害时额外能量的消耗。这种可以避免出现适合度代价的策略可能是昆虫应对环境压力的一种重要适应机制。

关键词: 橘小实蝇, GSTs, P450s, CCEs, 药剂胁迫, 组织特异性

Abstract: 【Objective】Based on the transcriptome data of Bactrocera dorsalis, the aim of this study is to systematically analyze the expression of genes in larvae encoding detoxification enzymes under β-cypermethrin exposure, identify important detoxification genes, and focus on the discussion of biological significance of tissue specific expression of these genes. 【Method】 The expressions of 30 detoxification genes in the whole body of larvae, midgut, and fat body were detected under β-cypermethrin exposure by using qPCR.【Result】Under the stress of β-cypermethrin, the qPCR results of 8 GSTs genes showed that the mRNA levels of 4 Delta class genes significantly increased. The expressions of genes from Delta class were up-regulated to 5.6-32.5 folds in the midgut and fat body, but the expressions of other GST genes did not show very active reaction when exposed to β-cypermethrin. Meanwhile, although the expressions of Delta class GSTs genes significantly increased in midgut and fat body, the expression changes of these genes were not so apparent in the whole body. As for the 6 CCEs genes, their expressions were up-regulated in some degree in the whole body, and α-E3 was up-regulated to 4.1 folds. However, in the midgut and fat body, the expressions of these genes did not increase significantly. The qPCR results of 16 P450s genes showed that the expressions of most P450s genes were up-regulated, especially the genes from CYP4 and CYP6 families. In CYP4 family, the expressions of CYP4D47 (midgut), CYP4E9 (whole body and fat body), CYP4P5 (whole body and fat body) were highly up-regulated. The expression of CYP4AD1 increased in some degree in the midgut and fat body, but no significant changes were found in the whole body. CYP4S18 and CYP4AC4 did not show any positive reaction or their expression changes were not apparent. In CYP6 family, the expressions of CYP6A48 and CYP6A41 had a significant increase in the fat body, 18.0 and 9.6 folds up-regulated, respectively. The expression of others like CYP6G6 and CYP6A50 also increased. The expression of CYP6EK1 was up-regulated by 4.8 folds in the whole body, but did not change in midgut and fat body. The expressions of the other genes, such as CYP12C2, CYP12N1, CYP9F6, and CYP309B1 also significantly increased in the fat body when exposed to β-cypermethrin. But the expression of CYP317B1 did not change under the stress.【Conclusion】When under the stress of β-cypermethrin, the detoxification genes in B. dorsalis larvae were highly enriched in midgut and fat body, but showed a balance in the whole body. It suggests that when under the toxic stress, the pests may have special strategy for efficient use and proper distribution of energy, which increase the energy efficiency to decrease the extra energy cost to resist the damage of exogenous toxin. This kind of strategy might be an important acclimation of insects to avoid fitness cost when under the environmental pressures.

Key words: Bactrocera dorsalis, GSTs, P450s, CCEs, toxic stress, tissue specificity