• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.186-188
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• 1996

곤충애 있어서 호르몬의 작용기작과 그 이용에 관하여 요야하면 다음과 같다. 곤충호르몬에는중추신경계의 신경분비세포에서 합성, 분비되는 peptide의 neuropeptide hormone (PTTH, bombyxin, diapause hormone등)이 있고, 상피계의 내분비선에서 합성, 분비되는 sesquiterpene의 유약호르몬 ( juvenile hormone)과 steroid의 탈피호르몬 (ecdysone)이 있다. 곤충호르몬은 특정한 표족세포에 있는 수용체와 높은 특이성과 높은 친화성을 가지고 결합해서 세포의 작용을 조절한다. 일반적으로 peptide hormone은 표적세포의의 세포막을 통과할 수 없으므로 표적세포의 막표면에 있는 수용체와 결합하는 것에 의해 세포내 대사제를 활성화시킴으로서 peptide hormone의 특이적인 발현이되는 것으로 알려지고 있다. 한편, ecdysone과 같은 steriod hormone이나 juvenlie hormone은 표적세포의 세포막을 용이하게 통과할수 있으므로 세포내의 세포막을 용이하게 통과할 수 있으므로 세포내로 들어가 수용체와 결합해서 hormone-receptor comlpex는 핵내로 들어가 DNA의 특이적인 영역에 결합하므로서 이들 호르몬 특이적인 기능이 발현되는 것으로 알려져 있다. Ecodysone의 활성이 있는 ecdysteroid가 여러 식물에서 발견되고 있어, 금후 양잠의 상족에 이용이 기대되고 있다. 또한, 향유약호르몬(AJH) 활성물지인 imidazole계 화합물은 양잠에 있어서 세섬도고치 생산에 그 이용이 기대되고 있다.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.15-28
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• 2022

Neuropeptides produced in neurosecretory cells are the largest group of insect hormones. They regulate various physiological functions, such as fat body homeostasis, feeding, digestion, excretion, circulation, reproduction, metamorphosis, and behavior throughout all life stages. The PRXamide peptide family (X, a variable amino acid) is a well-characterized neuropeptide component with a common amino acid sequence, PRXamide (NH₂), at the C-terminal end conserved across Insecta. The PRXamide peptides are classified into three subfamilies, each having diverse biological roles in insects: (1) pyrokinin (PK) includes the pheromone biosynthesis activating neuropeptide (PBAN) and the diapause hormone (DH), (2) the capability (CAPA) peptides, and (3) the ecdysis-triggering hormone (ETH). PBAN as a member of PK subfamily was first identified to stimulate pheromone biosynthesis in moths three decades ago. Since then, PBAN peptides have been extensively studied by various research groups from a broad spectrum of arthropods. In this paper, we briefly review insect PBAN molecules with emphasis on gene structure and expression, signal transduction, physiological mechanism in sex pheromone biosynthesis, and application for pest management.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.11-19
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• 2001

This review discusses the effects and roles of insect hormones and insect growth regulators (IGRs) on vitellogenesis in adult insects. Insect vitellogenesis is regulated by hormones such as juvenile hormone (JH), ecdysteroids, and neurosecretory hormones (ovaryecdysteroidogenic hormone : OEH) released by neurosecretory cells, diet, and other elements(male specific protein of sperm fluid). In the fat bodies, the vitellogenins are synthesized by the stimulation of JH released by corpus allatum (CA) and ecdysteroids produced by follicle cells with the ovary in most insects. Furthermore, vitellogenins are released into the hemolymph, transported to the ovarioles by carrier protein, and incorporated into oocytes for the developing ovary. Of IGRs, juvenile hormone and its mimics such as methoprene and pyriproxifen appear to have pharmacological effects such as membrane lysis, destruction of salivary grand and midgut epithlial cells, fat body cells, and ovarian tissue, and also anti-juvenile hormone such as precocenes I and II appear to have specific cytotoxicity such as inhibition of corpus allatum and oocytes development. These results suggest that IGRs may be useful as agents for integrated pest management.

• 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.

• Korean journal of applied entomology
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• v.31 no.2
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• pp.144-152
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• 1992

The juvenile hormone(JH) titers and juvenile hormone esterase (JHE) activities were mea¬sured in larval homogenates of the chestnut gall waL,J, Dryocosmus kuriphilus Yasumatsu, parasiting a susceptible and two resistant chestnut ( Cheuk-Pa, and Dan- Tak) varieties by GLC, Galleria wax test and Liquid scintilation counter. JH of the chestnut gall wasp was identified as JH- I. Their juvenile hormone titers were 35,800 GU/g(Cheuk-Pa), 30,900 GU/g (Dan-Tak), and 28,600 GU/g(susceptible variety). The juvenile hormone esterase activities were 1.48 n mole/min/ml(Cheuk-Pa), 1.63 n mole/min/ml(Dan- Tak), and 1.89 n mole/mini ml(susceptible variety). JH titer activity of the chestnut gall wasp parasiting resistant varie¬ties were higher than that from susceptible, whereas their JHE activity was higher in those from susceptible variety than those from resitant varieties. JH titer and JH specific esterase activity was inversely proportional.

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.202-205
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• 1996

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.189-196
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• 1996

• Korean journal of applied entomology
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• v.31 no.4
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• pp.329-337
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• 1992

Studies were carried out to investigate changes of lipid and carbohydrate contents in the hemolymph of the Oriental tobacco budworm(Helicoverpa assulta (Guenee» adults during flight and hormonal effects on mobilization of energy sources in the hemolymph. During a few minutes after flight, both sexes showed a rapid increase in lipid content and the high level was maintained for about 2 hours. But carbohydrate content in the hemolymph during flight showed almost no change but a slight increase seen during the first 10 min of flight in males only. Synthetic adipokinetic(Lom-AKH- n), hypertrehalosemic(Bld-HrTH) hormones and brain/ corpora cardiaca extract of H. assulta adult elevated lipid and carbohydrate contents in hemolymph and the effect was much more pronounced for lipid. These results suggested that lipid is a main fuel for flight activity and lipid mobilization is under the hormonal control. And this study showed that both adipokinetic and hypertrehalosemic factors may exist in H. assulta and these factors may have similar structures to those of Mas-AKH, Hez-HrTH, Lom-AKH- n or Pea-HrTH.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.258-264
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• 1991

Studies were carried out to investigate effects of temperature and photoperiod on diapause induction and of juvenile hormone III and 20-hydroxyecdysone treatment on diapausing adults of the alder leaf beetle, Agelastica coerulea Baly(Chrγsomelidae: Coleoptera). Its life cycle and ovarian development in adults were also observed. The beetle had one year life cycle with egg, larval, pupal and adult periods being 7-10, 19-21, 14-15 days and about 10 months, r respectively. All adults showed a diapause syndrome when the larvae were reared at $20^{\circ}C$ or $25^{\circ}C$ in combination of photoperiods of 16L/8D, 12L/12D, or 8L/16D. Their ovarioles did not s show any development of vitellogenesis before or during diapause and even when exposed at $15^{\circ}C$ after overwintering. When diapausing adults were treated with JH III they resumed feeding and laid several eggs and broke diapause condition temporally. But diapausing adults treated with 20-hydroxyecdysone did not show any response.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.85-90
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• 2022

Insulin and insulin-like growth factor-1 (IGF-1) are hormones that play an important role in the physiological regulation of metabolism, growth, and longevity in vertebrates. Likewise, insulin-like peptides (ILPs), which are structurally similar to insulin and IGF-1, are crucial in insect physiology. In this review, we present an integrated summary of insect ILPs and their receptor signaling, which has been shown to be comparable to insulin and IGF-1 receptor signaling in vertebrates based on genetic studies of Drosophila melanogaster. Additionally, we review the control of ILP synthesis and secretion in the brain in response to nutrition, as well as the ILPs' physiological role in insect metabolism. Moreover, we discuss the contribution of ILPs to growth, development, reproduction, and diapause. Finally, we consider the possibility of targeting ILP receptor signaling in pest management.