Molecular cloning and characterization of a juvenile hormone esterase gene from brown planthopper, Nilaparvata lugens
Molecular cloning and characterization of a juvenile hormone esterase gene from brown planthopper, Nilaparvata lugens
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DOI：
10.1016/j.jinsphys.2008.08.010
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发表时间：
2008-12-01
影响因子：
2.2
通讯作者：
Liu, Zewen
中科院分区：
文献类型：
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作者：
Liu, Shuhua;Yangb, Baojun;Liu, Zewen
保幼激素（JH）在昆虫生长、发育、滞育和繁殖的调节中发挥着关键作用，保幼激素酯酶（JHE）在调节JH滴度方面发挥着重要作用。我们在褐飞虱（NIJHE）中获得了编码 JHE 的全长 cDNA，这是从半翅目昆虫中克隆的第一个 JHE 基因。推导的 Nljhe 蛋白序列包含在其他昆虫物种的 JHE 中发现的五个保守基序，包括 JHE 蛋白酶活性所需的共有 GQSAG 基序。 Nljhe 与 Athalia rosae JHE (40%) 和 Apis mellifera JHE (39%) 显示出高度的氨基酸相似性。杆状病毒表达系统中表达的重组NIJHE蛋白以高活性水解[H-3] JH III，并产生与其他昆虫物种经验证的jHE接近的特异性常数(k(cat)/K-M = 4.28 x 10(6) M-1 s(-1))，表明Nljhe cDNA编码功能性JH酯酶。 Nljhe转录本主要在脂肪体中表达，在5龄若虫蜕皮后48 h表达量达到峰值。在第5龄，与蜕皮后不久和蜕皮后48小时在短翅昆虫中检测到的水平相比，大翅昆虫表现出显着较高的Nljhe mRNA水平和JHE活性，但JH III水平低得多。这些数据表明 NIJHE 可能在 JH 水平和翅膀形态分化的调节中发挥重要作用。 (c) 2008 Elsevier Ltd. 保留所有权利。
juvenile hormone (JH) plays key roles in the regulation of growth, development, diapause and reproduction in insects, and juvenile hormone esterase (JHE) plays an important role in regulating JH titers. We obtained a full-length cDNA encoding JHE in Nilaparvata lugens (NIJHE), the first JHE gene cloned from the hemipteran insects. The deduced protein sequence of Nljhe contains the five conserved motifs identified in JHEs of other insect species, including a consensus GQSAG motif that is required for the enzymatic activity of JHE Proteins. Nljhe showed high amino acid similarities with Athalia rosae JHE (40%) and Apis mellifera JHE (39%). Recombinant NIJHE protein expressed in the baculovirus expression system hydrolyzed [H-3] JH III at high activity and yielded the specificity constants (k(cat)/K-M = 4.28 x 10(6) M-1 s(-1)) close to those of the validated jHEs from other insect species, indicating that Nljhe cDNA encodes a functional JH esterase. The Nljhe transcript was expressed mainly in the fat body and the expression level reached a peak at 48 h after ecdysis of the 5th instar nymphs. In the 5th instar, macropterous insects showed significantly higher Nljhe mRNA levels and JHE activities, but much lower JH III levels, than those detected in the brachypterous insects soon after ecdysis and at 48 hafter ecdysis. These data suggest that NIJHE might play important roles in regulation of JH levels and wing form differentiation. (c) 2008 Elsevier Ltd. All rights reserved.