A5102962264- Neurobiology and Insect Physiology Research
- Insect and Arachnid Ecology and Behavior
- Insect and Pesticide Research
- Insect Utilization and Effects
- Insect-Plant Interactions and Control
- Insect Pest Control Strategies
- Insect Resistance and Genetics
- Phytochemical compounds biological activities
- Marine and fisheries research
- Estrogen and related hormone effects
- Analytical Chemistry and Chromatography
- Pesticide and Herbicide Environmental Studies
- Marine Biology and Environmental Chemistry
- Mass Spectrometry Techniques and Applications
- Pharmacological Effects and Assays
- Organic Chemistry Cycloaddition Reactions
- Plant biochemistry and biosynthesis
- Plant and animal studies
- Food Industry and Aquatic Biology
- Human Health and Disease
- Click Chemistry and Applications
- Physiological and biochemical adaptations
- Animal Behavior and Reproduction
- Cyclization and Aryne Chemistry
Institute of Agrobiological Sciences
2007-2023
National Agriculture and Food Research Organization
2020-2023
Shimane University
2010-2018
Tottori University
2014-2015
Kyushu University
2005-2011
Insect molting and metamorphosis are intricately governed by two hormones, ecdysteroids juvenile hormones (JHs). JHs prevent precocious allow the larva to undergo multiple rounds of until it attains proper size for metamorphosis. In silkworm, Bombyx mori, several "moltinism" mutations have been identified that exhibit variations in number larval molts; however, none them characterized molecularly. Here we report identification characterization gene responsible dimolting (mod) mutant...
Juvenile hormone (JH) I, II and III in the hemolymph of silkworm, Bombyx mori were quantified by liquid chromatography-mass spectrometry (LC-MS). JHs treated with methanol trifluoroacetic acid to convert into JH methoxyhydrines (JH-MHs). The key analytical condition for JH-MHs was addition 5 µM sodium acetate eluting solution. Each JH-MH observed as adduct ion good sensitivity. This improved method enabled titration silkworm be monitored from 3rd instar through early pupal stage. A peak I...
The insect GABA receptor (GABAR), which is composed of five RDL subunits, represents an important target for insecticides. A series 4,5-disubstituted 3-isoxazolols, including muscimol analogues, were synthesized and examined their activities against four splice variants (ac, ad, bc, bd) housefly GABARs expressed in Xenopus oocytes. Muscimol was a more potent agonist than all variants, whereas analogues did not exhibit agonism but rather antagonism GABARs. introduction bicyclic aromatic...
Insecticide resistance has recently become a serious problem in the agricultural field. Development of insecticides with new mechanisms action is essential to overcome this limitation. Juvenile hormone (JH) an insect-specific that plays key roles maintaining larval stage insects. Hence, JH signaling pathway considered suitable target development novel insecticides; however, only few inhibitors (JHSIs) have been reported, and no practical JHSIs developed. Here, we established high-throughput...
Insect GABA receptors (GABARs) represent important targets for insecticides. Thirteen iminopyridazine analogs were synthesized and evaluated their antagonism of three cloned insect GABARs. Of the analogs, 4-[4-cyclobutyl-1,6-dihydro-6-imino-3-(2-naphthyl)pyridazin-1-yl]butyronitrile greatly reduced GABA-activated responses in small brown planthopper (SBP) common cutworm (CC) GABARs at 100 µM. Removal cyclobutyl group did not affect levels inhibition both GABARs, whereas it increased housefly...
A number of ethyl 4-(2-benzylalkyloxy)benzoates were prepared and their activity to induce precocious metamorphosis was evaluated in larvae the silkworm, Bombyx mori, which clearly recognized as a juvenile hormone (JH)-deficiency symptom. Ethyl 4-(2-benzylhexyloxy)benzoate (6) its 2-benzylheptyloxy analog (7) found at relatively low doses. Both enantiomers 6 7 using chiral auxiliary oxazolidinone. (S)-Enatiomers more active than (R)-isomers doses 0.1 1 μg, but higher reversed. The compound...
Ethyl 4-[(6-substituted 2,2-dimethyl-2H-chromen-7-yl)methoxy]benzoates and their analogues were prepared the biological activities evaluated for both anti-juvenile hormone (anti-JH) JH activity in silkworm larvae, Bombyx mori. Of compounds tested, ethyl 4-[(6-methoxy-2,2-dimethyl-2H-chromen-7-yl)methoxy]benzoate (3b) showed most effective precocious metamorphosis-inducing 3rd instar larvae allatectomized 4th larvae. Furthermore, I 20-hydroxyecdysone (20-E) titers hemolymph of treated with 3b...
Ethyl 4-[2-(tert-butylcarbonyloxy)butoxy]benzoate (ETB) is a partial juvenile hormone (JH) antagonist which targets larval epidermis. We converted ETB to ethyl 4-(2-substituted alkyloxy)benzoates. These compounds induced precocious metamorphosis in the silkworm, Bombyx mori, clear sign of JH deficiency, and their activity was completely counteracted by simultaneous application agonist, methoprene. Among these novel compounds, 4-(2-benzylhexyloxy)benzoate (KF-13) showed high...
Juvenile hormone (JH) is an insect-specific that regulates molting and metamorphosis. Hence, JH signaling inhibitors (JHSIs) activators (JHSAs) can be used as effective insect growth regulators (IGRs) for pest management. In our previous study, we established a high-throughput screening (HTS) system exploration of novel JHSIs JHSAs using Bombyx mori cell line (BmN_JF&AR cells) succeeded in identifying from chemical library. Here, searched this system. The four-step HTS yielded 10 compounds...
A series of ethyl 4-[2-(6-methyl-3-pyridyloxy)alkyloxy]benzoates was prepared and tested for activity to induce precocious metamorphosis in larvae the silkworm, Bombyx mori. Of compounds tested, 4-[4-methyl-2-(6-methyl-3-pyridyloxy)pentyloxy]benzoate (5) most effective when applied 24 hr-old 3rd instar larvae. There no significant difference metamorphosis-inducing between 5R(+)- 5S(−)-enatiomers. The compound 5 could be fully counteracted by methoprene, a juvenile hormone (JH) agonist, but...
A series of ethyl 4-(2-benzylalkyloxy)benzoates possessing precocious metamorphosis-inducing activity showed juvenile hormone (JH) when topically applied to allatectomized 4th instar larvae Bombyx mori. Hexyl (KF-13) and heptyl analogs, which induced metamorphosis at low doses, had relatively high JH activity. In both compounds, (S)-enantiomers were more active than (R)-enantiomers. correlation was observed between anti-JH in the 4-(2-benzylalkyloxy)benzoate series. Replacement...
A series of ethyl 4-(2-aryloxyhexyloxy)benzoates was prepared and tested for their activity to induce precocious metamorphosis in larvae the silkworm. Phenyl analog 5 showed comparable that 6-methyl-3-pyridyl reported as a novel anti-JH agent. The could be fully counteracted by methoprene, JH agonist. ethoxycarbonyl group essential its activity.
A series of ethyl 4-[(7-substituted 1,4-benzodioxan-6-yl)methyl]benzoates was synthesized and evaluated for their anti-juvenile hormone (anti-JH) activities to induce precocious metamorphosis in silkworm (Bombyx mori) larvae. The introduction bulky alkyloxy substituents on the 7-position benzodioxan ring significantly increased activity. Ethyl 4-[(7-benzyloxy-1,4-benzodioxan-6-yl)methyl]benzoate (4c) showed most potent activity among test compounds, its median-effective dose (ED50) value 41...
Insect juvenile hormone (JH) agonists have been utilized as insect growth regulators for pest management against several species. We investigated insecticidal activity and the induction ratios of two JH-inducible genes, Krüppel homolog 1 (Kr-h1) broad (br), using 12 test compounds in western flower thrips Frankliniella occidentalis (Pergande). In assays propupae to inhibit metamorphosis adult, activities pyriproxyfen, KF-13, ETB, KF-31 were potent at 10 mM, while those other 8 chemicals not....
Since juvenile hormone (JH) is involved in a wide range of physiological processes both developing and mature insects (Riddiford, 1994), compounds that possess anti–JH activity are potentially useful not only as biochemical probes to assist elucidating the role JH insect development reproduction, but also growth regulators (Staal, 1986). Several including precocenes (Bowers et al., 1976), fluoromevalonate (Quistad 1981), ethyl 4–[2–(tert–butylcarbonyloxy)butyloxy]benzoate (ETB) 1982),...
A number of ethyl 4-[(1-substituted indol-2-yl)methoxy]benzoates and indoline derivatives were prepared as rigid congeners 4-(2-benzylhexyloxy)benzoate (KF-13), an anti-juvenile hormone (anti-JH) agent, tested for both anti-JH JH activities in silkworm larvae. In contrast to KF-13, the precocious metamorphosis-inducing activity which decreased by increasing applied doses, 1-n-propyl, 1-n-butyl (1c) 1-benzyl (1d) found induce higher percentages metamorphosis at high doses. Compounds 1c 1d...
Juvenile hormone (JH) plays a crucial role in insect development, reproduction and behavior, but its action at the molecular level is not well understood. In this study, design, synthesis biological evaluation of novel anti-JH agents were undertaken to obtain more effective chemicals assist elucidating mode JH. Ethyl 4-(2-benzylhexyloxy)benzoate (KF-13) ethyl 4-[(6-methoxy-2,2-dimethyl-2H-chromen-7-yl)methoxy]benzoate (KF-38) have been found show only highly precocious metamorphosis-inducing...