the chrysomelid species leptinotarsa decemlineata (say), commonly known as colorado potato beetle (cpb), is an important pest of potato and other solanaceous crops. the effects of precocene i and ii, juvenile hormone inhibitors, on morphological characteristics of the chemoreceptor organs of antennae and mouthparts of l. decemlineata larvae were studied in the laboratory. different doses of pre...

The antibiotic fungal metabolite sinefungin is a potent inhibitor of S-adenosylmethionineacceptor methyltransferases. Its effect on insect metabolism and especially on corpora allata farnesoic acid methyltransferase, which catalyzes the penultimate step of juvenile hormone biosynthesis, was investigated in Locusta migratoria. Injection of sinefungin results in a delay of imaginal molt and in su...

Brassinosteroids (BRs) are steroid hormones that regulate plant growth, development, and stress resistance. In this study, we evaluated the effect of agrochemicals on dark-induced hypocotyl elongation, which is regulated by BRs, to identify novel chemicals BR action. We found juvenile hormone agonist fenoxycarb inhibited elongation in Arabidopsis. Treatment with same class agonist, pyriproxyfen...

-A variety of water-miscible organic solvents caused profound activation of the homogeneous juvenile hormone esterase from Manduca sexta. Much lower activation was observed with other species. Methods for the handling of solutions of juvenile hormone are presented. The implications of solvent activation of juvenile hormone esterase activity are discussed, especially as they relate to analysis o...

In the cockroach Diploptera punctata, vitellogenic basal oocytes stimulate juvenile hormone production by the corpora allata. Experiments with males were designed to determine whether oocytes must grow vitellogenically in order to stimulate juvenile hormone production. Two ovarioles with vitellogenic basal oocytes were implanted into unoperated and sham-operated males that do not produce vitell...

The cDNA of the microsomal Juvenile Hormone Epoxide Hydrolase (JHEH) from Manduca sexta was expressed in vitro in the baculovirus system. In insect cell culture, the recombinant enzyme (Ms-JHEH) was produced at a high level (100 fold over background EH catalytic activity). As expected, Ms-JHEH was localized in the microsomal fraction with a molecular mass of approximately 50 kDa. Ms-JHEH showed...

By investigating the effects of recombinant juvenile hormone esterase (JHE) on the stimulation of ovarian development and egg laying in the house cricket Acheta domesticus L., we have tested the hypothesis that recombinant JHE (derived from the tobacco budworm Heliothis virescens) can be used as a biochemical anti-juvenile hormone (JH) agent. Recombinant JHE, produced by a genetically engineere...

Within a few hours after injection of juvenile hormone into Hyalophora gloveri pupae, several fast-migrating carboxylesterases (EC 3.1.1.1) that are sensitive to diisopropylfluorophosphate appear in the hemolymph. Treatment of the pupae with puromycin or actinomycin D prevents the appearance of these hemolymph enzymes, suggesting de novo synthesis of the carboxylesterases. Of the several other ...