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Archives of Biochemistry and Biophysics Mar 1970
Topics: Animals; Biological Assay; Bombyx; Chemistry Techniques, Analytical; Chromatography; Chromatography, Gas; Crystallization; Depression, Chemical; Ethyl Ethers; Female; Gonads; Growth; Hot Temperature; Hydrogen-Ion Concentration; Infrared Rays; Insecta; Invertebrate Hormones; Juvenile Hormones; Lipids; Magnetic Resonance Spectroscopy; Male; Metals; Methanol; Methods; Microchemistry; Solvents; Spectrophotometry; Spectrum Analysis; Waxes; Weights and Measures
PubMed: 5435056
DOI: 10.1016/0003-9861(70)90427-3 -
Pesticide Biochemistry and Physiology Dec 2023Destruxin A, a non-ribosomal peptide toxin produced by Metarhizium, exhibits potent insecticidal activity by targeting various tissues, organs, and cells of insects. Our...
Destruxin A, a non-ribosomal peptide toxin produced by Metarhizium, exhibits potent insecticidal activity by targeting various tissues, organs, and cells of insects. Our previous research has revealed that DA possesses the ability to bind to multiple proteins. In this study, we aimed to identify the most sensitive binding proteins of DA and investigate the physiological processes in which DA regulated. Through RNAi technology, we screened 22 binding proteins of DA in silkworm hemolymph. Among them, the juvenile hormone binding protein (JHBP), a hormone transport protein crucial for growth and development regulation, exhibited the highest sensitivity to DA. Subsequent experiments demonstrated that DA could inhibit the body weight gain of silkworm larvae, accelerate the pupation occurrence, and modulate the content of free juvenile hormone (JH) in the hemolymph. We also observed that DA could induce conformational changes in both the JHBP and the JHBP-JH binding complex. Notably, at low dosage, DA influenced the binding of JHBP to JH, while at high dosage, it irreversibly affected the binding of JHBP to JH. Molecular docking and point-mutant experiments suggested that DA might affect the N-arm of JHBP, which is responsible for JH binding. Additionally, we discovered that JHBP is widely distributed in various tissues of the silkworm, including the epidermis, gut, fat body, Malpighian tubule, gonad, muscle, trachea, and hemocyte. This study provides novel insights into the insecticidal mechanism of DA and enhances our understanding of the pathogenic process of Metarhizium.
Topics: Animals; Juvenile Hormones; Molecular Docking Simulation; Carrier Proteins; Moths; Bombyx; Insect Proteins
PubMed: 38072529
DOI: 10.1016/j.pestbp.2023.105654 -
Analytical Biochemistry Jan 2000A method for identification and quantitation of insect juvenile hormones (JH) has been developed using capillary gas chromatography-chemical ionization...
A method for identification and quantitation of insect juvenile hormones (JH) has been developed using capillary gas chromatography-chemical ionization (isobutane)-ion-trap mass spectroscopy. The method does not require derivatization of samples or use of selected ion monitoring. Analysis over a mass range of 60-350 u allowed for identification of as little as 0.01 pmol of individual JH homologs. Quantitative analysis was based on the ion intensities of six diagnostic ions and the summed intensities of these ions for each homolog. The ratio of diagnostic ions did not vary significantly over a range of concentrations from 2.7 to 200 pg. The technique was used to identify and quantify the amounts of JH homologs secreted by individual retrocerebral complexes from the moth Manduca sexta maintained in tissue culture and to identify JH III from hexane extracts of hemolymph of the Caribbean fruit fly. No discrimination due to disparate abundance ratios of the individual homologs was found when analyzing natural product samples differing in concentration by at least fivefold. The technique allows for facile, concrete identification and quantitation of biologically relevant amounts of JH. The ability to analyze samples without derivatization or fractionation by chromatographic methods, coupled with data acquisition over a broad mass range, provides levels of accuracy and confidence greater than those of other methods.
Topics: Animals; Insecta; Juvenile Hormones; Mass Spectrometry
PubMed: 10625507
DOI: 10.1006/abio.1999.4377 -
PloS One 2018Many plant species possess compounds with juvenile hormone disruptor (JHD) activity. In some plant species, such activity has been attributed to diterpene secondary...
Many plant species possess compounds with juvenile hormone disruptor (JHD) activity. In some plant species, such activity has been attributed to diterpene secondary metabolites. Plant JHD diterpenes disrupt insect development by interfering with the juvenile hormone (JH)-mediated formation of JH receptor complexes. Here, we demonstrate that a plant extract and a diterpene from Lindera erythrocarpa (methyl lucidone) interfere with the formation of both methoprene-tolerant (Met)/Taiman and Germ cell-expressed (GCE)/Taiman heterodimer complexes in yeast two-hybrid assays in vitro. In addition to the in vitro JHD activity, the diterpene and the plant extract from L. erythrocarpa also disrupt the development of larvae and pupae in Drosophila melanogaster. Comparing the transcriptomes of juvenile hormone analog (JHA, methoprene)- and JHD (methyl lucidone)-fed wandering third-instar larvae revealed a large number of genes that were coregulated by JHA and JHD. Moreover, most (83%) of the genes that were repressed by methyl lucidone were significantly activated by methoprene, indicating that JHDs and JHAs have opposing effects on the transcriptional regulation of many JH-dependent genes. Gene ontology analysis also suggested that some of the genes activated-by-JHA/repressed-by-JHD play roles in spermatogenesis. Affymetrix microarray-based analysis indicated that the expression of genes activated-by-JHA/repressed-by-JHD was testis-specific. Together, these results suggest that JH is involved in testis-specific gene expression and that plant JHD diterpenes function as JH antagonists in such JHA-mediated gene regulation.
Topics: Animals; Diterpenes; Drosophila melanogaster; Gene Expression Regulation, Developmental; Juvenile Hormones; Larva; Lindera; Plant Extracts
PubMed: 30011330
DOI: 10.1371/journal.pone.0200706 -
Nihon Naibunpi Gakkai Zasshi Nov 1976
Topics: Animals; Bombyx; Butterflies; Ecdysone; Hibernation; Insect Hormones; Juvenile Hormones; Moths; Neurosecretory Systems
PubMed: 1031671
DOI: No ID Found -
Environmental Health Perspectives Apr 1976Insect growth regulators (IGRs) are a class of new chemicals that interfere with maturation and reproduction in insects. Proposed hypotheses on the biochemical mechanism... (Review)
Review
Insect growth regulators (IGRs) are a class of new chemicals that interfere with maturation and reproduction in insects. Proposed hypotheses on the biochemical mechanism of action are presented herein. The environmental aspects as metabolism in soils, plants, insects, and animals suggest strongly that these chemicals undergo rapid degradation and metabolism to innocuous metabolites. The toxicological properties determined for registration of the IGR methoprene, isopropyl (E,E)-11-methoxy-3,7,11-trimethyl-2,4-dodecadienoate, reflected no significant effects against any of the species tested. Toxicological evaluations in swine, sheep, hamsters, rats, dogs, rabbits, guinea pigs, and cattle revealed no clinical signs of toxicosis. Additionally, teratological studies in swine, sheep, hamsters, rats, and rabbits also resulted in no observable effects in the animals at the levels administered.
Topics: Animals; Biodegradation, Environmental; Birds; Cricetinae; Crustacea; Dogs; Embryo, Mammalian; Embryo, Nonmammalian; Environmental Pollution; Female; Fishes; Insecta; Insecticides; Juvenile Hormones; Methoprene; Mice; Plants; Rabbits; Rats; Reproduction; Sheep; Swine
PubMed: 789059
DOI: 10.1289/ehp.7614127 -
Insect Science Apr 2018Methoprene, a juvenile hormone (JH) analog, is a widely used insecticide that also accelerates behavioral development in honey bees (Apis mellifera). JH regulates the...
Methoprene, a juvenile hormone (JH) analog, is a widely used insecticide that also accelerates behavioral development in honey bees (Apis mellifera). JH regulates the transition from nursing to foraging in adult worker bees, and treatment with JH or methoprene have both been shown to induce precocious foraging. To determine how methoprene changes honey bee behavior, we compared JH titers of methoprene-treated and untreated bees. Behavioral observations confirmed that methoprene treatment significantly increased the number of precocious foragers in 3 out of 4 colonies. In only 1 out of 4 colonies, however, was there a significant difference in JH titers between the methoprene-treated and control bees. Further, in all 4 colonies, there was no significant differences in JH titers between precocious and normal-aged foragers. These results suggest that methoprene did not directly affect the endogenous JH secreted by corpora allata. Because methoprene caused early foraging without changing workers' JH titers, we conclude that methoprene most likely acts directly on the JH receptors as a substitute for JH.
Topics: Animals; Bees; Behavior, Animal; Juvenile Hormones; Methoprene
PubMed: 27763722
DOI: 10.1111/1744-7917.12411 -
Biochimica Et Biophysica Acta. General... May 2018Bombyx mori silk fibers with thin diameters have advantages of lightness and crease-resistance. Many studies have used anti-juvenile hormones to induce trimolters in...
BACKGROUND
Bombyx mori silk fibers with thin diameters have advantages of lightness and crease-resistance. Many studies have used anti-juvenile hormones to induce trimolters in order to generate thin silk; however, there has been comparatively little analysis of the morphology, structure and mechanical properties of trimolter silk.
METHODS
This study induced two kinds of trimolters by appling topically anti-juvenile hormones and obtained thin diameter silk. Scanning electron microscope (SEM), FTIR analysis, tensile mechanical testing, chitin staining were used to reveal that the morphology, conformation and mechanical property of the trimolter silk.
RESULTS
Cocoon of trimolters were highly densely packed by thinner fibers and thus had small apertures. We found that the conformation of trimolter silk fibroin changed and formed more β-sheet structures. In addition, analysis of mechanical parameters yielded a higher Young's modulus and strength in trimolter silk than in the control. By chitin staining of silk gland, we postulated that the mechanical properties of trimolters' silk was enhanced greatly during to the structural changes of silk gland.
CONCLUSION
We induced trimolters by anti-juvenile hormones and the resulting cocoons were more closely packed and had smaller silk fiber diameters. We found that the conformation of trimolters silk fibroin had a higher content of β-sheet structures and better mechanical properties.
GENERAL SIGNIFICANCE
Our study revealed the structures and mechanical properties of trimolter silk, and provided a valuable reference to improve silk quality by influencing molting in silkworms.
Topics: Animals; Bombyx; Elastic Modulus; Imidazoles; Juvenile Hormones; Silk
PubMed: 29452235
DOI: 10.1016/j.bbagen.2018.02.007 -
Cold Spring Harbor Protocols Jul 2009Juvenile hormone (JH) is an important insect hormone known to have many effects on development, reproduction, and behavior in both solitary and social insects. A number...
Juvenile hormone (JH) is an important insect hormone known to have many effects on development, reproduction, and behavior in both solitary and social insects. A number of questions using ants as a model involve JH. This procedure allows for quantification of circulating levels of JH III, which can be an important factor in many questions relating to insect research. The JH III is extracted from a subject, purified, and converted to a d(3)-methoxyhydrin derivative that can be quantified by gas chromatography-mass spectrometry (GC-MS). The major advantages of this protocol are its high resolution, and its ability to quantify significant differences between relatively small quantities of the hormone. Its major limitations are the time necessary to process samples, its relatively high cost, and maintaining the sensitivity of the equipment.
Topics: Animals; Ants; Behavior, Animal; Biology; Gas Chromatography-Mass Spectrometry; Juvenile Hormones; Models, Animal; Social Behavior
PubMed: 20147211
DOI: 10.1101/pdb.prot5246 -
Annals of the New York Academy of... 1999Although sesquiterpenoids are probably the ancestral regulators of reproduction and secondarily of metamorphosis in arthropods, our discussion suggests that the... (Review)
Review
Although sesquiterpenoids are probably the ancestral regulators of reproduction and secondarily of metamorphosis in arthropods, our discussion suggests that the neuropeptides that regulate the biosynthesis of these compounds have arisen on several distinct occasions. These peptides probably occurred originally as regulators of other physiological processes and were subsequently co-opted for the regulation of sesquiterpenoid biosynthesis, perhaps first in adult forms and thereafter in larval forms. The evolution of peptides to assume additional physiological functions probably occurred as a result of gene duplication, both at the peptide level and at the receptor level. There are likely to be numerous regulators of sesquiterpenoid biosynthesis in both Insecta and Crustacea, and investigations to date have only begun to reveal the host of peptide families involved in the regulation of juvenile hormone-related biosynthesis across the arthropods.
Topics: Amino Acid Sequence; Animals; Arthropods; Biological Evolution; Homeostasis; Juvenile Hormones; Molecular Sequence Data; Sesquiterpenes; Sterols
PubMed: 10676458
DOI: 10.1111/j.1749-6632.1999.tb07901.x