Elayidam U Gayathri, Muraleedharen D
Department of Zoology, University of Kerala, Kariavattom, Thiruvanathapuram 695581, Kerala, India.
Indian J Biochem Biophys. 2008 Apr;45(2):121-5.
Juvenile hormone esterase (JHE), a selective enzyme that hydrolyzes the methyl ester of insect juvenile hormone plays an important role in regulating metamorphosis in nymphs as well as reproduction in adults. Studies on JH degradation provide insight into the possibilities of physiological disruption in the insects. In the present study, the JH degrading enzyme, JHE from the cotton pest Dysdercus cingulatus (Heteroptera) is characterized. Electrophoretic analysis of haemolymph during various developmental stages showed the JHE bands prominent only on the final day of 5th instar nymph, and the esterase substrate specificity confirmed the presence of JHE isoforms. In an attempt to clone cDNA of JHE gene from the final instar nymphs, mRNA isolated from fat bodies was coupled with JHE gene-specific primers and the cDNA was synthesized using RT-PCR. The PCR amplified cDNA showed the presence of JHE isoforms in D. cingulatus.
保幼激素酯酶（JHE）是一种能水解昆虫保幼激素甲酯的选择性酶，在调节若虫变态及成虫繁殖中发挥着重要作用。对保幼激素降解的研究有助于深入了解昆虫生理紊乱的可能性。在本研究中，对棉害虫红蝽（半翅目）的保幼激素降解酶JHE进行了特性分析。对不同发育阶段血淋巴的电泳分析表明，JHE条带仅在五龄若虫的最后一天显著，酯酶底物特异性证实了JHE同工型的存在。为了从末龄若虫中克隆JHE基因的cDNA，从脂肪体中分离的mRNA与JHE基因特异性引物结合，并使用逆转录聚合酶链反应（RT-PCR）合成cDNA。聚合酶链反应（PCR）扩增的cDNA显示红蝽中存在JHE同工型。
