Phenoloxidase and its zymogen are required for the larval-pupal transition in Bactrocera dorsalis (Diptera: Tephritidae)
Phenoloxidase and its zymogen are required for the larval-pupal transition in Bactrocera dorsalis (Diptera: Tephritidae)
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DOI：
10.1016/j.jinsphys.2014.10.013
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发表时间：
2014-12-01
影响因子：
2.2
通讯作者：
Wang, Jin-Jun
中科院分区：
文献类型：
--
作者：
Bai, Ping-Ping;Xie, Yi-Fei;Wang, Jin-Jun
苯酚氧化酶（POs）在黑色素生成中起关键作用，参与无脊椎动物的免疫机制，并被认为是昆虫发育过程中的重要酶。在本研究中，我们报道了背小实蝇BdPPO1的发育阶段和组织特异性表达模式以及PO活性。结果表明，PO的活性及其酶原的表达与桃粉蚧幼虫-蛹期的发育密切相关，尤其是在被体内。生化鉴定表明，不同发育阶段和组织的PO在pH 7.5和37℃时活性最高，饲喂含金属离子的人工饲料后，PO的活性和BdPPO1的表达均显著增加，说明PO是一种金属蛋白，可被Zn2+、Mg2+、Ca2+和Cu2+激活。功能分析显示，注射后20-羟基蜕皮激素（20E）可调节BdPPO1的表达。3龄幼虫注射BdPPO1双链RNA后，24 h和48 h mRNA水平显著降低，化蛹率降低，表型异常。这些结果扩大了对PO及其酶原在背芽孢杆菌生长中的重要作用的认识。(C) 2014 Elsevier Ltd.版权所有。
Phenoloxidases (POs) play a key role in melanin production, are involved in invertebrate immune mechanisms, and are considered important enzymes in the insect development process. In the present study, we report the developmental stage and tissue-specific expression patterns of BdPPO1 and PO activity from Bactrocera dorsalis. The results showed that the activity of PO and its zymogen expression were closely related to the development of B. dorsalis during the larval-pupal transition, particularly in the integument. Additionally, biochemical characterization showed that PO from different developmental stages and tissues all had maximum activity at pH 7.5 and 37 degrees C. After feeding a metal ion-containing artificial diet, the activity of PO and expression of BdPPO1 were significantly increased, indicating that PO was a metalloprotein and it could be activated by Zn2+, Mg2+, Ca2+, and Cu2+. The functional analysis showed that the expression of BdPPO1 could be regulated by 20-hydroxyecdysone (20E) after injection. Furthermore, injection of the double-stranded RNA of BdPPO1 into the 3rd instar larvae significantly reduced mRNA levels after 24 h and 48 h, and resulted in a lower pupation rate and abnormal phenotype. These results expand the understanding of the important role of PO and its zymogen in the growth of B. dorsalis. (C) 2014 Elsevier Ltd. All rights reserved.