Regulation of JH epoxide hydrolase versus JH esterase activity in the cabbage looper, Trichoplusia ni, by juvenile hormone and xenobiotics
Regulation of JH epoxide hydrolase versus JH esterase activity in the cabbage looper, Trichoplusia ni, by juvenile hormone and xenobiotics
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DOI：
10.1016/j.jinsphys.2004.12.008
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发表时间：
2005-05-01
影响因子：
2.2
通讯作者：
Roe, RM
中科院分区：
文献类型：
--
作者：
Anspaugh, DD;Roe, RM
比较了粉纹夜蛾（Trichoplusia ni）卵、幼虫、蛹和成虫的JH Ⅲ酯酶和JH Ⅲ环氧化物水解酶（EH）的体外活性。虽然这两种酶的活性检测在所有年龄测试，JH酯酶显着高于EH活性，除了第三天的第五（最后）体育场（L5 D3）。对于这两种酶来说，活性都很高。-藏在蛋里。成年处女女性有4.6和4.0倍高的JH酯酶和EH活性，分别比成年处女男性。JH III代谢活性也在第五阶段T ni的全身匀浆中测量，所述第五阶段T ni被喂食营养性饮食（对照）或饥饿于无营养性饮食的琼脂、琼脂和水。饥饿6，28和52小时的幼虫，每只昆虫当量的EH活性分别为对照昆虫的48%，5%和1%。在同一时间点，饥饿状态下的昆虫JH酯酶活性水平分别为营养饲料的29%、4%和3%。选定的昆虫激素和外源性物质局部或口服给第五期幼虫长达52小时，全身EH和JH酯酶活性的影响进行了分析。JH III使JH III酯酶活性增加高达2.2倍，但不增加JH III EH活性。JH类似物甲氧普烯使JH酯酶和EH活性增加高达2.5倍。JH酯酶抑制剂3-辛硫基-1，1，1-三氟丙-2-酮（OTFP）对EH活性无影响。在单独的实验中，环氧化物反式和顺式二苯乙烯氧化物（TSO和CSO）使EH活性增加约2.0倍。TSO没有改变JH酯酶水平时，局部应用，但口服给药降低活性的70%的控制在28小时，然后增加活性1.8倍，在52小时后开始治疗。CSO对JH酯酶活性无影响。苯巴比妥使EH活性增加1.9倍，但不改变JH酯酶水平。氯贝特和胆固醇5 α，6 α-环氧化物对EH无影响。JH酯酶活性也不受氯贝特的影响，但胆固醇5 α，6 α-环氧化物使JH酯酶活性降低至对照的60-80%。这些结果的生物学意义进行了讨论。(C)2005爱思唯尔有限公司保留所有权利。
JH III esterase and JH III epoxide hydrolase (EH) in vitro activity was compared in whole body Trichoplusia ni homogenates at each stage of development (egg, larva, Pupa and adult). While activity of both enzymes was detected at all ages tested, JH esterase was significantly higher than EH activity except for day three of the fifth (last) stadium (L5D3). For both enzymes, activity was hi.-hest in eggs. Adult virgin females had 4.6- and 4.0-fold higher JH esterase and EH activities, respectively, than adult virgin males. JH III metabolic activity also was measured in whole body homogenates of fifth stadium T ni that were fed a nutritive diet (control) or starved on a non-nutritive diet of alphacel, agar and water. With larvae that were starved for 6, 28 and 52 h, EH activity per insect equivalent was 48%, 5% and 1%, respectively, of the control insects. At the same time points, JH esterase activity levels in starved T ni were 29%, 4% and 3% of that of insects fed the nutritive diet. Selected insect hormones and xenobiotics were administered topically or orally to fifth stadium larvae for up to 52 h, and the effects on whole body EH and JH esterase activity analyzed. JH III increased the JH Ill esterase activity as high as 2.2-fold, but not the JH III EH activity. The JH analog, methoprene, increased both JH esterase and EH activity as high as 2.5-fold. The JH esterase inhibitor, 3-octylthio-1,1,1-trifluoropropan-2-one (OTFP), had no impact on EH activity. The epoxides trans- and cis-stilbene oxide (TSO and CSO) in separate experiments increased the EH activity approximately 2.0-fold. TSO did not alter JH esterase levels when topically applied, but oral administration reduced activity to 70% of the control at 28 h, and then increased the activity 1.8-fold at 52 h after the beginning of treatment. CSO had no effect on JH esterase activity. Phenobarbital increased EH activity by 1.9-fold, but did not change JH esterase levels. Clofibrate and cholesterol 5 alpha,6 alpha-epoxide had no effect on EH. JH esterase activity also was not affected by clofibrate, but cholesterol 5 alpha, 6 alpha-epoxide reduced the JH esterase activity to 60-80% of the control. The biological significance of these results is discussed. (C) 2005 Elsevier Ltd. All rights reserved.