昆虫学报 ›› 2019, Vol. 62 ›› Issue (11): 1250-1259.doi: 10.16380/j.kcxb.2019.11.002

• 研究论文 • 上一篇    下一篇

重金属镉胁迫对白纹伊蚊幼虫海藻糖代谢的影响

俞玲园, 魏莹, 陈旭敏, 丁艳娟, 胡耀文, 唐斌, 王世贵*   

  1. (杭州师范大学生命与环境科学学院, 杭州 310036)
  • 出版日期:2019-11-20 发布日期:2019-11-05

Effects of heavy metal cadmium on the trehalose metabolism in Aedes albopictus (Diptera: Culicidae) larvae

YU Ling-Yuan, WEI Ying, CHEN Xu-Min, DING Yan-Juan, HU Yao-Wen, TANG Bin, WANG Shi-Gui   

  1. (College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China)
  • Online:2019-11-20 Published:2019-11-05

摘要: 【目的】深入了解镉对白纹伊蚊Aedes albopictus的毒害作用机理和白纹伊蚊对极端环境的适应机制,揭示重金属胁迫对白纹伊蚊种群发生、疾病传播等可能存在的影响,为卫生害虫防控等提供参考依据。【方法】分别用200 mL配制好的50, 100, 200, 300和400 mg/L镉溶液对放置于320 mL一次性杯中长势一致的白纹伊蚊3龄末至4龄初幼虫急性染毒12 h,以双蒸水养殖幼虫作为对照。通过生化方法测定处理后12 h白纹伊蚊幼虫体内海藻糖、葡萄糖和总糖原含量以及可溶性海藻糖酶(TRE1)和膜结合型海藻糖酶(TRE2)活力,并采用qRTPCR测定这些幼虫体内海藻糖合成酶基因(TPS), TRE1和TRE2表达量。【结果】在200和300 mg/L重金属镉处理12 h时白纹伊蚊幼虫海藻糖含量显著增加,在高镉浓度(300和400 mg/L)处理时葡萄糖含量显著下降,而不同镉浓度急性处理对总糖原含量没有影响。TRE1和TRE2活力在高镉浓度(300和400 mg/L)处理时显著下降。300 mg/L镉处理组TPS相对表达量达到最高值,TRE1和TRE2相对表达量在高镉浓度(300和400 mg/L)处理时显著下降,与酶活力变化趋势表现一致。【结论】当镉浓度低于半致死浓度(217 mg/L)时,镉急性胁迫使白纹伊蚊幼虫TPS基因表达上调,而TRE基因则表达量下降,TRE活力降低,从而促使葡萄糖转化为海藻糖,通过海藻糖的积累来应对镉胁迫压力。这些结果说明海藻糖在白纹伊蚊在重金属应激中起一定作用,白纹伊蚊幼虫可以通过合成海藻糖从而提高应对镉胁迫的抗逆能力。

关键词: 白纹伊蚊, 重金属, 镉胁迫, 海藻糖, 海藻糖代谢

Abstract: 【Aim】 This study aims to understand the toxic effects of cadmium on Aedes albopictus and its adaptation to the extreme environment, and to reveal the possible effects of heavy metal stress on the occurrence of mosquitoes and disease transmission, so as to provide reference for the control of hygienic pests. 【Methods】 The late 3rd instar to early 4th instar larvae of A. albopictus with the same growth status in 320 mL disposable cups were acutely exposed to 200 mL prepared 50, 100, 200, 300, and 400 mg/L Cd2+ solution, respectively, for 12 h, and the larvae cultured in double distilled water were used as the control. The contents of trehalose, sucrose and total glycogen, and the activities of soluble trehalase (TRE1) and membrane-bound trehalase (TRE2) in the larvae at 12 h post treatment were determined by biochemical methods, and the relative expression levels of trehalose-6-phosphate synthase gene (TPS), TRE1 and TRE2 in these larvae were detected by qRT-PCR. 【Results】 The results showed that the trehalose content in A. albopictus larvae exposed to 200 and 300 mg/L Cd2+ solution for 12 h increased significantly, while the glucose content in larvae exposed to high concentrations of Cd2+ solution (300 and 400 mg/L) decreased significantly, as compared with the control. The acute treatment of different Cd2+ concentrations had no effect on the total glycogen content. The activities of TRE1 and TRE2 in larvae exposed to high concentrations of Cd2+ (300 and 400 mg/L) decreased significantly as compared with those in the control group. The relative expression level of TPS was the highest in the 300 mg/L Cd2+ treated group. The relative expression levels of TRE1 and TRE2 in larvae exposed to high concentrations of Cd2+ solution (300 and 400 mg/L) decreased significantly as compared with those in the control group. 【Conclusion】 The acute stress of Cd2+ up-regulates the expression of TPS gene in A. albopictus larvae when the Cd2+ concentration is lower than the LC50 value (217 mg/L), while the relative expression level of TRE gene and the TRE activity decrease,  thereby promoting the conversion of glucose to trehalose and resisting the Cd2+ stress by the production of trehalose. These results indicate that trehalose may play a role in heavy metal stress in A. albopictus larvae, which can improve the resistance to Cd2+ stress by trehalose synthesis.

Key words: Aedes albopictus, heavy metal, cadmium stress, trehalose, trehalose metabolism