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Insect Biochemistry and Molecular... 2000
Review
Topics: Animals; Corpora Allata; Forecasting; History, 18th Century; History, 19th Century; History, 20th Century; Juvenile Hormones; Protein Binding; Research
PubMed: 10876106
DOI: 10.1016/s0965-1748(00)00034-5 -
Tropical Biomedicine Sep 2021Juvenile hormone is an exclusive hormone found in insects which involves regulating various insect physiology. A total of eight juvenile hormones have been identified in... (Review)
Review
Juvenile hormone is an exclusive hormone found in insects which involves regulating various insect physiology. A total of eight juvenile hormones have been identified in insects which include JH 0, JH I, JH II, JH III, 4-methyl JH I (Iso- JH 0), JHB III, JHSB III, and MF. Corpora allata are the glands responsible for the production and synthesis of these hormones. They are involved in moulting, reproduction, polyethism, and behavioural regulations in different orders of insects. Factors such as diet temperatures, photoperiods, and plant compounds affect the biosynthesis and regulation of juvenile hormones. Juvenile hormones analogue is usually used to disrupt normal regulation of JH and this analogue is categorized as insect-growth regulators (IGRs) and is widely used in pest control as an alternative to chemical insecticides. Other applications of biosynthesis activities of this hormone have not been explored in the area of JHs. In this review, current applications of JHs with an addition of their future application will be discussed.
Topics: Animals; Corpora Allata; Insecta; Juvenile Hormones; Molting; Pest Control
PubMed: 34362868
DOI: 10.47665/tb.38.3.066 -
Insect Biochemistry and Molecular... 2000This paper argues that the current dogma that juvenile hormones are structurally unique and constitute a family of derivatives of farnesoic acid which are produced by... (Review)
Review
This paper argues that the current dogma that juvenile hormones are structurally unique and constitute a family of derivatives of farnesoic acid which are produced by the corpus allatum (CA), secreted into the hemolymph, frequently transported by binding proteins, enter cells by diffusion across the cell membrane and there the products of the CA interact in some way with the genome, probably via nuclear receptors of the steroid superfamily, may not be tenable. It does so by examining the following questions. How many JHs are there? Are there other sources of JH in insects? Are there non-farnesoids with JH activity in insects? How does JH get into cells? Is the product of the CA the effective hormone? How many modes of action are there? How many receptors are there?
Topics: Animals; Juvenile Hormones
PubMed: 10876109
DOI: 10.1016/s0965-1748(00)00037-0 -
Archives of Insect Biochemistry and... Mar 2020Synthetic compounds that mimic the action of juvenile hormones (JHs) are founding members of a class of insecticides called insect growth regulators (IGRs). Like JHs,... (Review)
Review
Synthetic compounds that mimic the action of juvenile hormones (JHs) are founding members of a class of insecticides called insect growth regulators (IGRs). Like JHs, these juvenoids block metamorphosis of insect larvae to reproductive adults. Many biologically active juvenoids deviate in their chemical structure considerably from the sesquiterpenoid JHs, raising questions about the mode of action of such JH mimics. Despite the early deployment of juvenoid IGRs in the mid-1970s, their molecular effect could not be understood until recent discoveries of JH signaling through an intracellular JH receptor, namely the ligand-binding transcription factor Methoprene-tolerant (Met). Here, we briefly overview evidence defining three widely employed and chemically distinct juvenoid IGRs (methoprene, pyriproxyfen, and fenoxycarb), as agonist ligands of the JH receptor. We stress that knowledge of the target molecule is critical for using these compounds both as insecticides and as research tools.
Topics: Animals; Gene Expression Regulation, Developmental; Insecticide Resistance; Insecticides; Juvenile Hormones; Ligands; Metamorphosis, Biological; Methoprene; Phenylcarbamates; Pyridines; Structure-Activity Relationship
PubMed: 31502704
DOI: 10.1002/arch.21615 -
Ecotoxicology and Environmental Safety Dec 2022Environmental pollution and resistance in animals are major concerns for the application of synthetic pesticides. Diallyl trisulfide (DAT), an active compound in garlic...
Environmental pollution and resistance in animals are major concerns for the application of synthetic pesticides. Diallyl trisulfide (DAT), an active compound in garlic essential oil, is a novel tool for active and safe control of agricultural insect pests. In this study, we analysed the effects of DAT (0.01 μL/L) on the protein content in male reproductive tissues (accessory glands, ejaculatory ducts, and testis), and juvenile hormone (JH) and ecdysone titres in a highly detrimental pest of stored products, Sitotroga cerealella. Evaluation of the expression profile of JH and ecdysone pathway-related genes in various tissues indicated that the accessory gland protein and ecdysone titres were markedly decreased after DAT fumigation, whereas the testis protein content and JH titre were increased. However, the protein content of the ejaculatory ducts remained unchanged between the treated and control groups. Further investigation revealed that DAT disrupted the mRNA expression of key enzymes involved in JH and ecdysone pathways. While increased mRNA levels of juvenile hormone acid O-methyltransferase (JHMAT) and Kruppel homologue 1 (Kr-h1) were observed after 4 and 7 h of DAT fumigation, the levels of juvenile hormone epoxide hydrolase (JHEH) were substantially reduced 3 h post-fumigation. mRNA levels of the ecdysone-responsive gene, FTZF1, and cytochrome P450 enzyme, CYP315A1, were notably decreased at 7 h and 4 h, respectively, post-fumigation, whereas CYP314A1 and CYP302A1 mRNA levels decreased after 3 h and 4 h, respectively. While DAT fumigation disrupted sperm number in the testis, ejaculatory ducts, and seminal vesicles, topical application of the 20-hydroxyecdysone (20E) analogue also lowered sperm number in the ejaculatory ducts. Topical application of methoprene, a JH analogue, increased the protein content in the testes, but not in the accessory glands or ejaculatory ducts. However, the survival rate was not affected by the topical application of methoprene or 20E. These data suggest that DAT regulates JH and ecdysone via its molecular pathway genes and modulates endocrine secretion during the male reproductive process.
Topics: Male; Animals; Ecdysone; Methoprene; Seeds; Juvenile Hormones; Garlic
PubMed: 36403303
DOI: 10.1016/j.ecoenv.2022.114304 -
Journal of Agricultural and Food... May 2023Juvenile hormone (JH) plays an important role in regulating various insect physiological processes. Herein, a novel method (chiral and achiral) for the simultaneous...
Juvenile hormone (JH) plays an important role in regulating various insect physiological processes. Herein, a novel method (chiral and achiral) for the simultaneous detection of five JHs was established by processing a whole insect without complicated hemolymph extraction. The proposed method was used to determine the distribution of JHs in 58 insect species and the absolute configuration of JHs in 32 species. The results showed that JHSB was uniquely synthesized in Hemiptera, JHB was unique to Diptera, and JH I and JH II were unique to Lepidoptera. JH III was present in most insect species surveyed, with social insects having generally higher JH III titers. Interestingly, JHSB and JHB, both double epoxidation JHs, were found in insects with sucking mouthparts. The absolute conformation of JH III and the 10C of the detected JHs were all stereoisomers.
Topics: Animals; Insecta; Juvenile Hormones; Diptera; Lepidoptera; Stereoisomerism
PubMed: 37191197
DOI: 10.1021/acs.jafc.3c01168 -
General and Comparative Endocrinology Sep 2020The sesquiterpenoid juvenile hormone(s) (JHs) of insects are the primary regulators of growth, metamorphosis, and reproduction in most insect species. As a consequence,... (Review)
Review
The sesquiterpenoid juvenile hormone(s) (JHs) of insects are the primary regulators of growth, metamorphosis, and reproduction in most insect species. As a consequence, it is essential that JH production be precisely regulated so that it is present only during appropriate periods necessary for the control of these processes. The presence of JH at inappropriate times results in disruption to metamorphosis and development and, in some cases, to disturbances in female reproduction. Neuropeptides regulate the timing and production of JH by the corpora allata. Allatostatin and allatotropin were the names coined for neuropeptides that serve as inhibitors or stimulators of JH biosynthesis, respectively. Three different allatostatin neuropeptide families are capable of inhibiting juvenile hormone but only one family is utilized for that purpose dependent on the insect studied. The function of allatotropin also varies in different insects. These neuropeptides are pleiotropic in function acting on diverse physiological processes in different insects such as muscle contraction, sleep and neuromodulation. Genome projects and expression studies have assigned individual neuropeptide families to their respective receptors. An understanding of the localization of these receptors is providing clues as to how numerous peptide families might be integrated in regulating physiological functions. In recent years microRNAs have been identified that down-regulate enzymes and transcription factors that are involved in the biosynthesis and action of juvenile hormone.
Topics: Amino Acid Sequence; Animals; Evolution, Molecular; Insect Hormones; Juvenile Hormones; MicroRNAs; Neuropeptides
PubMed: 32413346
DOI: 10.1016/j.ygcen.2020.113507 -
Vitamins and Hormones 2023During the past 15years, after confirming Methoprene tolerant (Met) as a juvenile hormone (JH) receptor, tremendous progress has been made in understanding the function...
During the past 15years, after confirming Methoprene tolerant (Met) as a juvenile hormone (JH) receptor, tremendous progress has been made in understanding the function of Met in supporting JH signal transduction. Met role in JH regulation of development, including metamorphosis, reproduction, diapause, cast differentiation, behavior, im`munity, sleep and epigenetic modifications, have been elucidated. Met's Heterodimeric partners involved in performing some of these functions were discovered. The availability of JH response elements (JHRE) and JH receptor allowed the development of screening assays in cell lines and yeast. These screening assays facilitated the identification of new chemicals that function as JH agonists and antagonists. These new chemicals and others that will likely be discovered in the near future by using JH receptor and JHRE will lead to highly effective species-specific environmentally friendly insecticides for controlling pests and disease vectors.
Topics: Humans; Methoprene; Juvenile Hormones; Cell Differentiation; Epigenesis, Genetic; Reproduction
PubMed: 37718000
DOI: 10.1016/bs.vh.2023.03.002 -
Annual Review of Entomology 2013The molecular action of juvenile hormone (JH), a regulator of vital importance to insects, was until recently regarded as a mystery. The past few years have seen an... (Review)
Review
The molecular action of juvenile hormone (JH), a regulator of vital importance to insects, was until recently regarded as a mystery. The past few years have seen an explosion of studies of JH signaling, sparked by a finding that a JH-resistance gene, Methoprene-tolerant (Met), plays a critical role in insect metamorphosis. Here, we summarize the recently acquired knowledge on the capacity of Met to bind JH, which has been mapped to a particular ligand-binding domain, thus establishing this bHLH-PAS protein as a novel type of an intracellular hormone receptor. Next, we consider the significance of JH-dependent interactions of Met with other transcription factors and signaling pathways. We examine the regulation and biological roles of genes acting downstream of JH and Met in insect metamorphosis. Finally, we discuss the current gaps in our understanding of JH action and outline directions for future research.
Topics: Animals; Gene Expression Regulation, Developmental; Insecta; Juvenile Hormones; Metamorphosis, Biological; Methoprene; Transcription Factors
PubMed: 22994547
DOI: 10.1146/annurev-ento-120811-153700 -
Biochemical and Biophysical Research... Nov 1997The in vitro production of sesquiterpenoids was investigated by using corpora allata (CA) of the African locust Locusta migratoria migratorioides. Labeled products from...
The in vitro production of sesquiterpenoids was investigated by using corpora allata (CA) of the African locust Locusta migratoria migratorioides. Labeled products from unstimulated biosynthesis were extracted, purified by normal phase HPLC, and derivatized to determine the functional groups present. An extra hydroxyl group was detected in each of two juvenile hormone (JH) biosynthetic products. One compound, NP-8, was found to co-migrate with a chemically-synthesized (Z)-hydroxymethyl isomer, 12'-OH JH-III, but not with the (E)-hydroxymethyl isomer, 12-OH JH III. Mass spectral analyses further supported the identity of the synthetic material with that biosynthesized by the corpora allata. A second compound was identified as the 8'-OH JH-III based on spectroscopic analyses. 12'-OH JH-III exhibited morphogenetic activity when tested on the heterospecific Tenebrio test. These data suggest that 12'-OH JH-III and 8'-OH JH-III are additional biosynthetically-produced and biologically-active juvenile hormones, and constitute the first known members of the class of hydroxy juvenile hormones (HJHs).
Topics: Animals; Chromatography, High Pressure Liquid; Corpora Allata; Grasshoppers; Hydroxylation; Juvenile Hormones; Mass Spectrometry; Molecular Structure; Morphogenesis; Sesquiterpenes; Spectrum Analysis; Tenebrio; Vitellogenesis
PubMed: 9398639
DOI: 10.1006/bbrc.1997.7739