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Junki Saito, Ryota Kimura, Yuya Kaieda, Ritsuo Nishida, Hajime Ono
Early steps of the biosynthetic pathway of the insect steroid hormone ecdysone remains the "Black Box" wherein the characteristic ecdysteroid skeleton is built. 7-Dehydrocholesterol (7dC) is the precursor of uncharacterized intermediates in the Black Box. The oxidation step at C-3 has been hypothesized during conversion from 7dC to 3-oxo-2,22,25-trideoxyecdysone, yet 3-dehydroecdysone is undetectable in some insect species. Therefore, we first confirmed that the oxidation at C-3 occurs in the fruitfly, Drosophila melanogaster using deuterium-labeled cholesterol...
September 20, 2016: Journal of Insect Physiology
Panagiotis Moulos, Martina Samiotaki, George Panayotou, Skarlatos G Dedos
The cells of prothoracic glands (PG) are the main site of synthesis and secretion of ecdysteroids, the biochemical products of cholesterol conversion to steroids that shape the morphogenic development of insects. Despite the availability of genome sequences from several insect species and the extensive knowledge of certain signalling pathways that underpin ecdysteroidogenesis, the spectrum of signalling molecules and ecdysteroidogenic cascades is still not fully comprehensive. To fill this gap and obtain the complete list of cell membrane receptors expressed in PG cells, we used combinatory bioinformatic, proteomic and transcriptomic analysis and quantitative PCR to annotate and determine the expression profiles of genes identified as putative cell membrane receptors of the model insect species, Bombyx mori, and subsequently enrich the repertoire of signalling pathways that are present in its PG cells...
2016: Scientific Data
J Zheng, K Tian, Y Yuan, M Li, X Qiu
20-Hydroxyecdysone (20E) is a key hormone which regulates growth, development and reproduction in insects. Although cytochrome P450 enzymes (P450s) participating in the ecdysteroid biosynthesis of 20E have been characterized in a few model insects, no work has been published on the molecular entity of their orthologs in the cotton bollworm Helicoverpa armigera, a major pest insect in agriculture worldwide. In this study, four cytochrome P450 homologs, namely HarmCYP302A1, HarmCYP306A1, HarmCYP314A1 and HarmCYP315A1 from H...
August 22, 2016: Bulletin of Entomological Research
Jin-Ching Lee, Fang-Rong Chang, Shu-Rong Chen, Yu-Hsuan Wu, Hao-Chun Hu, Yang-Chang Wu, Anders Backlund, Yuan-Bin Cheng
A new marine ecdysteroid with an α-hydroxy group attaching at C-4 instead of attaching at C-2 and C-3, named palythone A (1), together with eight known compounds (2-9) were obtained from the ethanolic extract of the Formosan zoanthid Palythoa mutuki. The structures of those compounds were mainly determined by NMR spectroscopic data analyses. The absolute configuration of 1 was further confirmed by comparing experimental and calculated circular dichroism (CD) spectra. Anti-dengue virus 2 activity and cytotoxicity of five isolated compounds were evaluated using virus infectious system and [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assays, respectively...
2016: Marine Drugs
Xanthe Vafopoulou, Colin G H Steel
The actions of the insect steroid molting hormones, ecdysteroids, on the genome of target cells has been well studied, but little is known of their extranuclear actions. We previously showed in Rhodnius prolixus that much of the ecdysteroid receptor (EcR) resides in the cytoplasm of various cell types and undergoes shuttling between nucleus and cytoplasm with circadian periodicity, possibly using microtubules as tracks for translocation to the nucleus. Here we report that cytoplasmic EcR appears to be also involved in extranuclear actions of ecdysteroids by association with the mitochondria...
October 1, 2016: General and Comparative Endocrinology
Siddharth Jayakumar, Shlesha Richhariya, O Venkateswara Reddy, Michael J Texada, Gaiti Hasan
Neuronal circuits are known to integrate nutritional information, but the identity of the circuit components is not completely understood. Amino acids are a class of nutrients that are vital for the growth and function of an organism. Here, we report a neuronal circuit that allows Drosophila larvae to overcome amino acid deprivation and pupariate. We find that nutrient stress is sensed by the class IV multidendritic cholinergic neurons. Through live calcium imaging experiments, we show that these cholinergic stimuli are conveyed to glutamatergic neurons in the ventral ganglion through mAChR...
2016: ELife
Rosemary Viola Bosch, Miryam Paola Alvarez-Flores, Durvanei Augusto Maria, Ana Marisa Chudzinski-Tavassi
Fibroblasts are the main cellular component of connective tissues and play important roles in health and disease through the production of collagen, fibronectin and growth factors. Under certain conditions, such as wound healing, fibroblasts intensify their metabolic demand, while the restriction of nutrients affect matrix composition, cell metabolism and behavior. In lepidopterans, wound healing is regulated by ecdysteroid hormones, which upregulate multifunctional proteins such as hemolin. However, the role of hemolin in cell proliferation and wound healing is not clear...
August 2016: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
Baojian Zhu, Lishang Dai, Yingying Yu, Daojun Wang, Tao Peng, Chaoliang Liu
A suppressor of cytokine signaling 2 (SOCS-2) homolog was identified from the red crayfish Procambarus clarkii. Phylogenic analysis showed that P. clarkii SOCS-2 (Pc-SOCS-2) was very similar to that of invertebrates. The sequence contains a central SH2 domain, a conserved SOCS box, and a variable N-terminal domain. Real-time polymerase chain reaction showed that Pc-SOCS-2 mRNA level was higher in muscle and heart than in the other tissues examined. A 40-kDa recombinant protein was successfully expressed and purified from Escherichia coli cells as confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting...
August 2016: Journal of Experimental Zoology. Part A, Ecological Genetics and Physiology
Zi-Yue Zhang, Wei-Qun Yang, Chun-Lin Fan, Hui-Nan Zhao, Xiao-Jun Huang, Ying Wang, Wen-Cai Ye
Three new ecdysteroid glycosides (1-3) and one new ecdysteroid (4), were isolated from the roots of Serratula chinensis. Their structures were established on the basis of extensive spectroscopic analysis and chemical methods.
July 18, 2016: Journal of Asian Natural Products Research
Shin G Goto
Photoperiodism is an adaptive, seasonal timing system that enables organisms to coordinate their development and physiology to annual changes in the environment using day length (photoperiod) as a cue. This review summarizes our knowledge of the physiological mechanisms underlying photoperiodism in spider mites. In particular, the two-spotted spider mite Tetranychus urticae is focussed, which has long been used as a model species for studying photoperiodism. Photoperiodism is established by several physiological modules, such as the photoreceptor, photoperiodic time measurement system, counter system, and endocrine effector...
July 16, 2016: Journal of Comparative Physiology. B, Biochemical, Systemic, and Environmental Physiology
H S da Rosa, A C F Salgueiro, A Z C Colpo, F R Paula, A S L Mendez, V Folmer
Sida tuberculata (Malvaceae) is a medicinal plant traditionally used in Brazil as an antimicrobial and anti-inflammatory agent. Here, we aimed to investigate the different extractive techniques on phytochemical parameters, as well as to evaluate the toxicity and antioxidant capacity of S. tuberculata extracts using in silico and in vitro models. Therefore, in order to determine the dry residue content and the main compound 20-hydroxyecdysone (20E) concentration, extracts from leaves and roots were prepared testing ethanol and water in different proportions...
July 11, 2016: Brazilian Journal of Medical and Biological Research, Revista Brasileira de Pesquisas Médicas e Biológicas
Ashley Booth, Enmin Zou
Polybrominated diphenyl ethers (PBDEs) are environmentally pervasive flame retardants that have been linked with endocrine disruption in a variety of organisms. BDE-47, one of the most prevalent congeners found in aquatic environments, has recently been shown to inhibit crustacean molting, but little is known about the specific mechanism through which molt-inhibition occurs. This study examined whether the inhibitory effect on molting arises from the disruption of hormone signaling in the epidermis using the blue crab, Callinectes sapidus, as the model crustacean...
August 2016: Aquatic Toxicology
Kang Li, Ling Tian, Zhongjian Guo, Sanyou Guo, Jianzhen Zhang, Shi-Hong Gu, Subba R Palli, Yang Cao, Sheng Li
The temporal control mechanisms that precisely control animal development remain largely elusive. The timing of major developmental transitions in insects, including molting and metamorphosis, is coordinated by the steroid hormone 20-hydroxyecdysone (20E). 20E involves feedback loops to maintain pulses of ecdysteroid biosynthesis leading to its upsurge, whereas the underpinning molecular mechanisms are not well understood. Using the silkworm Bombyx mori as a model, we demonstrated that E75, the 20E primary response gene, mediates a regulatory loop between ecdysteroid biosynthesis and 20E signaling...
August 26, 2016: Journal of Biological Chemistry
Danuše Tarkowská, Miroslav Strnad
The present review summarises current knowledge of phytoecdysteroids' biosynthesis, distribution within plants, biological importance and relations to plant hormones. Plant ecdysteroids (phytoecdysteroids) are natural polyhydroxylated compounds that have a four-ringed skeleton, usually composed of either 27 carbon atoms or 28-29 carbon atoms (biosynthetically derived from cholesterol or other plant sterols, respectively). Their physiological roles in plants have not yet been confirmed and their occurrence is not universal...
September 2016: Planta
Dae-Sik Hwang, Jeonghoon Han, Eun-Ji Won, Duck-Hyun Kim, Chang-Bum Jeong, Un-Ki Hwang, Bingsheng Zhou, Joonho Choe, Jae-Seong Lee
2,2',4,4'-Tetrabromodiphenyl ether (BDE-47) is a persistent organic pollutant (POP) in marine environments. Despite its adverse effects (e.g. developmental retardation) in ecdysozoa, the effects of BDE-47 on transcription of ecdysteroid signaling pathway-involved-nuclear receptor (NR) genes and metamorphosis-related genes have not been examined in copepods. To examine the deleterious effect of BDE-47 on copepod molting and metamorphosis, BDE-47 was exposed to the harpacticoid copepod Tigriopus japonicus, followed by monitoring developmental retardation and transcriptional alteration of NR genes...
August 2016: Aquatic Toxicology
Yin Ning Chiang, Kah Junn Tan, Henry Chung, Oksana Lavrynenko, Andrej Shevchenko, Joanne Y Yew
Many of the lipids found on the cuticles of insects function as pheromones and communicate information about age, sex, and reproductive status. In Drosophila, the composition of the information-rich lipid profile is dynamic and changes over the lifetime of an individual. However, the molecular basis of this change is not well understood. To identify genes that control cuticular lipid production in Drosophila, we performed a RNA interference screen and used Direct Analysis in Real Time and gas chromatography mass spectrometry to quantify changes in the chemical profiles...
June 2016: PLoS Genetics
Xi Xie, Yanqi Zhou, Mingxin Liu, Tian Tao, Qinghua Jiang, Dongfa Zhu
The nuclear receptor E75 is an early-responsive gene in 20-hydroxyecdysone (20E) signaling pathway, and is found to play essential roles in many aspects of arthropods development. In this study, a cDNA encoding the E75 nuclear receptor of the swimming crab, Portunus trituberculatus was cloned using RT-PCR and RACE. The PtE75 cDNA was 3211bp in length, and encodes a protein of 795 amino acids. The DBD region of the predicted amino acid sequence for PtE75 was highly conserved with other arthropoda E75s, while its LBD region was more similar to decapod E75s...
October 2016: Comparative Biochemistry and Physiology. Part B, Biochemistry & Molecular Biology
Kiyun Park, Chamilani Nikapitiya, Won-Seok Kim, Tae-Soo Kwak, Ihn-Sil Kwak
Irgarol is a common antifoulant present in coastal sediment. The mud crab Macrophthalmus japonicus is one of the most abundant of the macrobenthos in the costal environment, and its exoskeleton has a protective function against various environmental threats. We evaluated the effects of irgarol toxicity on the exoskeleton of M. japonicus, which is the outer layer facing the environment. We analyzed transcriptional expression of exoskeleton, molting, and proteolysis-related genes in the gill and hepatopancreas of these exposed M...
October 2016: Ecotoxicology and Environmental Safety
Tomotsune Ameku, Ryusuke Niwa
Mating and gametogenesis are two essential components of animal reproduction. Gametogenesis must be modulated by the need for gametes, yet little is known of how mating, a process that utilizes gametes, may modulate the process of gametogenesis. Here, we report that mating stimulates female germline stem cell (GSC) proliferation in Drosophila melanogaster. Mating-induced increase in GSC number is not simply owing to the indirect effect of emission of stored eggs, but rather is stimulated by a male-derived Sex Peptide (SP) and its receptor SPR, the components of a canonical neuronal pathway that induces a post-mating behavioral switch in females...
June 2016: PLoS Genetics
Ian J Rowland, Walter G Goodman
Non-invasive 3D magnetic resonance imaging techniques were used to investigate metamorphosis of the alimentary tract of Manduca sexta from the larval to the adult stage. The larval midgut contracts in volume immediately following cessation of feeding and then greatly enlarges during the late pharate pupal period. Magnetic resonance imaging revealed that the foregut and hindgut of the pharate pupa undergo ecdysis considerably earlier than the external exoskeleton. Expansion of air sacs in the early pupa and development of flight muscles several days later appear to orient the midgut into its adult position in the abdomen...
2016: PloS One
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