• The Korean Journal of Zoology
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• v.36 no.2
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• pp.238-244
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• 1993

We identified juvenile hormone binding protein (JHBP) from last instar larval hemollvnph of Hvphantria cunea using gel filtration and non-SDS PAGE. Two kinds of JHBP in hemollnnph were found at two peaks by gel filtration (Sephadex G-100) and also at Rm values of 0.13 and 0.57 by non-SDS PAGE. JHBP was partially purified using anion exchange chromatosraphv, preparative gel filteration, and preparative PAGE. Dextrin coated charcoal (DCC) binding assay was employed to monitor the location of JHBP in chromatographic profile during the purification process. Purity of JHBP was checked by silver staining of 1091 SDS-Polyacrvlamide.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.196-202
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• 1991

Juvenile honnone binding protein (JHBP) was identified in the last instar larval hemolymph of Lymantria dispar using dextran coated charcoal (DCC) binding assay and gel filtration. The p1 value of JHBP was estimated to be 5.3. JHBP was partially pudfied by polyethylene glycol(PEG) precipitation, DEAE-cellulose ion-exchange chromatography and gel filtration, and was confirmed by DCC binding assay.

• The Korean Journal of Zoology
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• v.37 no.4
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• pp.495-503
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• 1994

Hemolymph SHBP (hJHBP) was partially purified from last instar larvae of Bombyx zori by gel filtration and their optimal reaction conditions of dextrin coated charcoal binding assay were determined. Dissociation constant (KD) of hJHBP for JH III was calculated to be 1.45 $\times$ 10-7 M at $4^{\circ}C.$ The molecular weight of hJHBP was estimated to be 30 kDa by gel filtration on a calibrated Sephadex G-100 column and 33 kDa by SDS-PAGE. These results indicate that hSHBP consists of a single polvpeptide chain. Isoelectric point of hJHBP was found to be pH 5.1 and 19 of the first 20 amino acid residues were determined from N-terminus of purified hJHBP.

• The Korean Journal of Zoology
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• v.37 no.1
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• pp.66-75
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• 1994

Juvenile hormone binding protein was identified in the hemolymph of fifth instar larvae and purified using column chromatography. Hemolymph was mixed with [3H] JH-III and electrophoresed on 691 NON-SDS gel, indicating that radioactivity peak appears at Rf value of 0.55. Gel filtration showed two radioactivity peaks equivalent to bound and free [3H]JH-III, respectively. JHBP was purified from hemolymph through gel filtration (Sephadex G-100), anion exchange chromatosraphv (DEAE Sepharose CL-6B), chromatofocusing chromatographv (PBE 94) and preparative electrophoresis.

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.183.2-183
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• 1994

• Korean journal of applied entomology
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• v.37 no.1
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• pp.59-64
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• 1998

A juvenile hormone binding protein (JHBP) has been isolated from the whole body homogenate of Galleria rnellonella final instar larvae by gel filtration. The isolated protein is homogenous as judged by column chromatography and gel electrophoresis in the presence and absence of denaturing agent. The JHBP has a relative molecular weight of 32 k by denaturing gel electrophresis and 28 k by gel filtration. The protein exhibits a dissociation constant of 3.9 x M for JH 111.

• Korean Journal of Environmental Biology
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• v.40 no.3
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• pp.255-266
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• 2022

In crustaceans, molting is regulated by interactions between ecdysteroid and juvenile hormone (JH) signaling pathway-related genes. Unlike the ecdysteroid signaling pathway, little information on the role of JH signaling pathway-related genes in molting is available in zooplanktonic crustaceans. In this study, three genes (juvenile hormone acid O-methyltransferase (JHAMT), methoprene-tolerant (Met), and juvenile hormone epoxide hydrolase (JHEH)) which are involved in the synthesis, receptor-binding, and degradation of JH were identified using sequence and phylogenetic analysis in the brackish water flea, Diaphanosoma celebensis. Transcriptional changes in these genes during the molting cycle in D. celebensis were analyzed. Sequence and phylogenetic analysis revealed that these putative proteins may be functionally conserved along with those of insects and other crustaceans. In addition, the expression of the three genes was correlated with the molting cycle of D. celebensis, indicating that these genes may be involved in the synthesis and degradation of JH, resulting in normal molting. This study will provide information for a better understanding of the role of JH signaling pathway-related genes during the molting process in Cladocera.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.101-108
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• 2022

Because of their specificity to target insects and relatively low toxicity to non-target organisms, insect growth regulators (IGRs) have been regarded as attractive alternatives to chemical insecticides. Commercially available IGRs are classified into juvenile hormone agonists (JHAs), ecdysone agonists (EAs), and chitin synthesis inhibitors (CSIs) according to their mode of action. Recently, JH-mediated interaction of methoprene-tolerant (Met), which is JH receptor, and its binding partners have been replicated in vitro using yeast cells transformed with the Met and FISC/CYC genes of A. aegypti. Using this in vitro yeast two-hybrid β-galactosidase assay, juvenile hormone antagonists (JHANs) have been identified from various sources including chemical libraries, plants, and microorganisms. As juvenile hormone (JH) is an insect specific hormone and regulates development, reproduction, diapause and other physiological processes, JHANs fatally disrupt the endocrine signals, which result in abnormal development and larval death. These results suggested that JHANs could be efficiently applied as IGR insecticides with a broad insecticidal spectrum. This review discuses JH signaling pathway mediated by Met and future prospects of JHANs as environmentally benign IGR insecticides.

• Journal of Sericultural and Entomological Science
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• v.30 no.1
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• pp.25-32
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• 1988

In order to examine a physiological role of juvenile(JH) binding proteins in the hemolymph of the silkworm larva, Bombyx mori, [3H] JH I incubated hemolymph was separated by polyacrylamide gel electrophoresis in the fifth-instar larva and the activity of the binding protein was analyzed using charcoal binding assay. The results obtained were as follows; 1. The JH was bound by two protein fractions in the hemolymph of the fifth-instar larva; One was JH binding lipoprotein(JH-LP), the other was JH speific binding protein(JHBP). Their relative mobility values(Rm) were 0.3∼0.33 and 0.81∼0.84, respectively. There were no valid differences in those values from developmental stages of both male and female silkworms. 2. Total protein contents of the hemolymph were gradually increased during the fifth-instar larva, while at the prepupa decreased. The maximum ones were observed at the spinning period and the contents from female were much higher than those from the male. 3. JH binding activity per ml of the hemolymph was low in the early stage of the fifth-instar larva and its activity was maximized at the psinning period and at the prepupa slightly decreased. 4. There was a similar pattern between changes of the JH binding activity per ml of the hemolymph and of the total protein contents of the hemolymph. 5. The JH binding activity per mg of the hemolymph proteins was high in the early stage of the fifth-instar larva, while from the 6th day of the fifth-instar larva to the prepupa its activity showed the lowest levels.

• Korean journal of applied entomology
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• v.43 no.2
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• pp.143-153
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• 2004

Non-spinning syndrome of Bombyx mori has been serious issue in sericulture industry near Kyungbuk area. This study was focused on the analysis of the mechanism and on screening candidate chemicals inducing the anti-metamorphosis of the silkworms. Rearing temperatures or initial body weight of the final instar larvae did not affect a normal larval to pupal metamorphosis of B. mori. However, pyriproxyfen (a juvenile hormone (JH) agonist) induced follicle patency significantly even at its 10$\^$-8/ M concentration and inhibited metamorphosis of B. mori in both developmental time and dose dependent manners. Pyriproxyfen induced JH esterase (JHE) activity and downregulated expression of JH binding protein of 5. mori. These results suggests that pyriproxyfen induced JHE activity as a JH agonist and that the elevated JHE activity degraded endogenous JH and resulted in JHBP gene expression. Based on the fact that the JH agonist induced follicle patency and inhibited metamorphosis of B. mori, follicle patency bioassay suggested that three commercial pesticides including simazine, molinate or alachlor were proved to give potent JH agonistic effect on B. mori. Further direct exposure experiments to these candidates are required to determine the chemicals responsible for the non-spinning syndrome of 8. mori.