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Taro Mito - One of the best experts on this subject based on the ideXlab platform.
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Bone morphogenetic protein signaling in distal patterning and intercalation during leg regeneration of the cricket, Gryllus bimaculatus.
Development growth & differentiation, 2018Co-Authors: Yoshiyasu Ishimaru, Sumihare Noji, Tetsuya Bando, Hideyo Ohuchi, Taro MitoAbstract:The cricket, Gryllus bimaculatus, is a classic model of leg regeneration following amputation. We previously demonstrated that Gryllus decapentaplegic (Gb'dpp) is expressed during leg regeneration, although it remains unclear whether it is essential for this process. In this study, double-stranded RNA targeting the Smad mathers-against-dpp homolog, Gb'mad, was used to examine the role of bone morphogenetic protein (BMP) signaling in the leg regeneration process of Gryllus bimaculatus. RNA interference (RNAi)-mediated knockdown of Gb'mad led to a loss of tarsus regeneration at the most distal region of regenerating leg segments. Moreover, we confirmed that the phenotype obtained by knockdown of Dpp type I receptor, Thick veins (Gb'tkv), closely resembled that observed for Gb'mad RNAi crickets, thereby suggesting that the BMP signaling pathway is indispensable for the initial stages of tarsus formation. Interestingly, knockdown of Gb'mad and Gb'tkv resulted in significant elongation of regenerating tibia along the proximodistal axis compared with normal legs. Moreover, our findings indicate that during the regeneration of tibia, the BMP signaling pathway interacts with Dachsous/Fat (Gb'Ds/Gb'Ft) signaling and dachshund (Gb'dac) to re-establish positional information and regulate determination of leg size. Based on these observations, we discuss possible roles for Gb'mad in the distal patterning and intercalation processes during leg regeneration in Gryllus bimaculatus.
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Genome Editing in the Cricket, Gryllus bimaculatus
Methods in molecular biology (Clifton N.J.), 2017Co-Authors: Takahito Watanabe, Sumihare Noji, Taro MitoAbstract:Hemimetabolous, or incompletely metamorphosing, insects are phylogenetically basal and include many beneficial and deleterious species. The cricket, Gryllus bimaculatus, is an emerging model for hemimetabolous insects, based on the success of RNA interference (RNAi)-based gene-functional analyses and transgenic technology. Taking advantage of genome editing technologies in this species would greatly promote functional genomics studies. Genome editing has proven to be an effective method for site-specific genome manipulation in various species. Here, we describe a protocol for genome editing including gene knockout and gene knockin in G. bimaculatus for functional genomics studies.
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Eye Development and Photoreception of a Hemimetabolous Insect, Gryllus bimaculatus
The Cricket as a Model Organism, 2017Co-Authors: Hideyo Ohuchi, Tetsuya Bando, Taro Mito, Sumihare NojiAbstract:The hemimetabolous insect, Gryllus bimaculatus, has two compound eyes that begin to form in the embryo and increase in size five- to sixfolds during nymphal development. Retinal stemlike cells reside in the anteroventral proliferation zone (AVPZ) of the nymphal compound eye and proliferate to increase retinal progenitors, which then differentiate to form new ommatidia in the anterior region of the eye. Here, we introduce the morphology and development of the cricket eye first, and then we focus on the roles of retinal determination genes (RDGs) such as eyes absent (eya) and sine oculis (so) in Gryllus eye formation and growth. Since the principal function of the eye is photoreception, we finally summarize opsin photopigments in this species, broadening the roles of photoreception.
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gene knockout by targeted mutagenesis in a hemimetabolous insect the two spotted cricket Gryllus bimaculatus using talens
Methods, 2014Co-Authors: Takahito Watanabe, Sumihare Noji, Taro MitoAbstract:Hemimetabolous, or incompletely metamorphosing, insects are phylogenetically basal. These insects include many deleterious species. The cricket, Gryllus bimaculatus, is an emerging model for hemimetabolous insects, based on the success of RNA interference (RNAi)-based gene-functional analyses and transgenic technology. Taking advantage of genome-editing technologies in this species would greatly promote functional genomics studies. Genome editing using transcription activator-like effector nucleases (TALENs) has proven to be an effective method for site-specific genome manipulation in various species. TALENs are artificial nucleases that are capable of inducing DNA double-strand breaks into specified target sequences. Here, we describe a protocol for TALEN-based gene knockout in G. bimaculatus, including a mutant selection scheme via mutation detection assays, for generating homozygous knockout organisms.
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caudal is required for gnathal and thoracic patterning and for posterior elongation in the intermediate-germband cricket Gryllus bimaculatus.
Mechanisms of development, 2005Co-Authors: Yohei Shinmyo, Taro Mito, Hideyo Ohuchi, Katsuyuki Miyawaki, Takashi Matsushita, Isao Sarashina, Sumihare NojiAbstract:Although the molecular mechanisms directing anteroposterior patterning of the Drosophila embryo (long-germband mode) are well understood, how these mechanisms were evolved from an ancestral mode of insect embryogenesis remains largely unknown. In order to gain insight into mechanisms of evolution in insect embryogenesis, we have examined the expression and function of the orthologue of Drosophila caudal (cad) in the intermediate-germband cricket Gryllus bimaculatus. We observed that a posterior (high) to anterior (low) gradient in the levels of Gryllus bimaculatus cad (Gb' cad) transcript was formed in the early-stage embryo, and then Gb' cad was expressed in the posterior growth zone until the posterior segmentation was completed. Reduction of Gb' cad expression level by RNA interference resulted in deletion of the gnathum, thorax, and abdomen in embryos, remaining only anterior head. We found that the gnathal and thoracic segments are formed by Gb' cad probably through the transcriptional regulation of gap genes including Gb' hunchback and Gb' Kruppel. Furthermore, Gb' cad was found to be involved in the posterior elongation, acting as a downstream gene in the Wingless/Armadillo signalling pathways. These findings indicate that Gb' cad does not function as it does in Drosophila, suggesting that regulatory and functional changes of cad occurred during insect evolution. Since Wnt/Cdx pathways are involved in the posterior patterning of vertebrates, such mechanisms may be conserved in animals that undergo sequential segmentation from the posterior growth zone.
Sumihare Noji - One of the best experts on this subject based on the ideXlab platform.
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Bone morphogenetic protein signaling in distal patterning and intercalation during leg regeneration of the cricket, Gryllus bimaculatus.
Development growth & differentiation, 2018Co-Authors: Yoshiyasu Ishimaru, Sumihare Noji, Tetsuya Bando, Hideyo Ohuchi, Taro MitoAbstract:The cricket, Gryllus bimaculatus, is a classic model of leg regeneration following amputation. We previously demonstrated that Gryllus decapentaplegic (Gb'dpp) is expressed during leg regeneration, although it remains unclear whether it is essential for this process. In this study, double-stranded RNA targeting the Smad mathers-against-dpp homolog, Gb'mad, was used to examine the role of bone morphogenetic protein (BMP) signaling in the leg regeneration process of Gryllus bimaculatus. RNA interference (RNAi)-mediated knockdown of Gb'mad led to a loss of tarsus regeneration at the most distal region of regenerating leg segments. Moreover, we confirmed that the phenotype obtained by knockdown of Dpp type I receptor, Thick veins (Gb'tkv), closely resembled that observed for Gb'mad RNAi crickets, thereby suggesting that the BMP signaling pathway is indispensable for the initial stages of tarsus formation. Interestingly, knockdown of Gb'mad and Gb'tkv resulted in significant elongation of regenerating tibia along the proximodistal axis compared with normal legs. Moreover, our findings indicate that during the regeneration of tibia, the BMP signaling pathway interacts with Dachsous/Fat (Gb'Ds/Gb'Ft) signaling and dachshund (Gb'dac) to re-establish positional information and regulate determination of leg size. Based on these observations, we discuss possible roles for Gb'mad in the distal patterning and intercalation processes during leg regeneration in Gryllus bimaculatus.
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Genome Editing in the Cricket, Gryllus bimaculatus
Methods in molecular biology (Clifton N.J.), 2017Co-Authors: Takahito Watanabe, Sumihare Noji, Taro MitoAbstract:Hemimetabolous, or incompletely metamorphosing, insects are phylogenetically basal and include many beneficial and deleterious species. The cricket, Gryllus bimaculatus, is an emerging model for hemimetabolous insects, based on the success of RNA interference (RNAi)-based gene-functional analyses and transgenic technology. Taking advantage of genome editing technologies in this species would greatly promote functional genomics studies. Genome editing has proven to be an effective method for site-specific genome manipulation in various species. Here, we describe a protocol for genome editing including gene knockout and gene knockin in G. bimaculatus for functional genomics studies.
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Eye Development and Photoreception of a Hemimetabolous Insect, Gryllus bimaculatus
The Cricket as a Model Organism, 2017Co-Authors: Hideyo Ohuchi, Tetsuya Bando, Taro Mito, Sumihare NojiAbstract:The hemimetabolous insect, Gryllus bimaculatus, has two compound eyes that begin to form in the embryo and increase in size five- to sixfolds during nymphal development. Retinal stemlike cells reside in the anteroventral proliferation zone (AVPZ) of the nymphal compound eye and proliferate to increase retinal progenitors, which then differentiate to form new ommatidia in the anterior region of the eye. Here, we introduce the morphology and development of the cricket eye first, and then we focus on the roles of retinal determination genes (RDGs) such as eyes absent (eya) and sine oculis (so) in Gryllus eye formation and growth. Since the principal function of the eye is photoreception, we finally summarize opsin photopigments in this species, broadening the roles of photoreception.
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gene knockout by targeted mutagenesis in a hemimetabolous insect the two spotted cricket Gryllus bimaculatus using talens
Methods, 2014Co-Authors: Takahito Watanabe, Sumihare Noji, Taro MitoAbstract:Hemimetabolous, or incompletely metamorphosing, insects are phylogenetically basal. These insects include many deleterious species. The cricket, Gryllus bimaculatus, is an emerging model for hemimetabolous insects, based on the success of RNA interference (RNAi)-based gene-functional analyses and transgenic technology. Taking advantage of genome-editing technologies in this species would greatly promote functional genomics studies. Genome editing using transcription activator-like effector nucleases (TALENs) has proven to be an effective method for site-specific genome manipulation in various species. TALENs are artificial nucleases that are capable of inducing DNA double-strand breaks into specified target sequences. Here, we describe a protocol for TALEN-based gene knockout in G. bimaculatus, including a mutant selection scheme via mutation detection assays, for generating homozygous knockout organisms.
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functional analysis of the circadian clock gene period by rna interference in nymphal crickets Gryllus bimaculatus
Journal of Insect Physiology, 2009Co-Authors: Yoshiyuki Moriyama, Sumihare Noji, Tomoaki Sakamoto, Akira Matsumoto, Kenji TomiokaAbstract:The circadian clock gene period (Gryllus bimaculatus period, Gb'per) plays a core role in circadian rhythm generation in adults of the cricket Gryllus bimaculatus. We examined the role of Gb'per in nymphal crickets that show a diurnal rhythm rather than the nocturnal rhythm of the adults. As in the adult optic lobes, Gb'per mRNA levels in the head of the third instar nymphs showed daily cycling in light-dark cycles with a peak at mid night, and the rhythm persisted in constant darkness. Injection of Gb'per double-stranded RNA (dsRNA) into the abdomen of third instar nymphs knocked-down the mRNA levels to 25% of that in control animals. Most Gb'per dsRNA injected nymphs lost their circadian locomotor activity rhythm, while those injected with DsRed2 dsRNA as a negative control clearly maintained the rhythm. These results suggest that nymphs and adults share a common endogenous clock mechanism involving the clock gene Gb'per.
Shinji Nagata - One of the best experts on this subject based on the ideXlab platform.
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Behavioral tracing demonstrates dietary nutrient discrimination in two-spotted crickets Gryllus bimaculatus
Bioscience biotechnology and biochemistry, 2017Co-Authors: Keisuke Fukumura, Shinji NagataAbstract:Animals select appropriate diets to meet their nutritional requirements. Here, we demonstrate the availability for analysis of feeding preference using an orthopteran, the two-spotted cricket Gryllus bimaculatus. A time-course study of these insects, involving continuous recording and tracing behavior for 9 h, allowed us to monitor discrimination of diet that contained various nutrients.
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Newly identified allatostatin Bs and their receptor in the two-spotted cricket, Gryllus bimaculatus.
Peptides, 2016Co-Authors: Yusuke Tsukamoto, Shinji NagataAbstract:Abstract A cDNA encoding allatostatin Bs (ASTBs) containing the W(X)6W motif was identified using a database generated by a next generation sequencer (NGS) in the two-spotted cricket, Gryllus bimaculatus. The contig sequence revealed the presence of five novel putative ASTBs (GbASTBs) in addition to GbASTBs previously identified in G. bimaculatus. MALDI-TOF MS analyses revealed the presence of these novel and previously identified GbASTBs with three missing GbASTBs. We also identified a cDNA encoding G. bimaculatus GbASTB receptor (GbASTBR) in the NGS data. Phylogenetic analysis demonstrated that this receptor was highly conserved with other insect ASTBRs, including the sex peptide receptor of Drosophila melanogaster. Calcium imaging analyses indicated that the GbASTBR heterologously expressed in HEK293 cells exhibited responses to all identified GbASTBs at a concentration range of 10−10–10−5 M.
Tom Tregenza - One of the best experts on this subject based on the ideXlab platform.
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New microsatellite loci isolated from the field cricket Gryllus bimaculatus characterized in two cricket species, Gryllus bimaculatus and Gryllus campestris
Molecular ecology resources, 2008Co-Authors: Amanda Bretman, Deborah A. Dawson, Gavin J. Horsburgh, Tom TregenzaAbstract:We have developed a new set of 27 polymorphic markers for each of two cricket species, Gryllus bimaculatus and Gryllus campestris. Initially, 14 published G. bimaculatus loci were tested in G. campestris; however, only five loci were polymorphic. Therefore, we isolated an additional 50 new microsatellite loci from G. bimaculatus and tested these in both species. In a minimum of 20 individuals, 27 of the new loci were polymorphic in G. bimaculatus and 25 in G. campestris.
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Sexual selection in the cricket Gryllus bimaculatus: no good genes?
Genetica, 2008Co-Authors: Rolando Rodríguez-muñoz, Amanda Bretman, Jarrod D Hadfield, Tom TregenzaAbstract:Recent studies have suggested that females of the field cricket Gryllus bimaculatus exercise post-copulatory choice over the paternity of their offspring. There is evidence that these choices are made in relation to the genetic compatibility of mates rather than their absolute quality, but the magnitude of heritable differences in males has not been thoroughly examined. Using a half-sib breeding design we measured additive genetic variance and dam effects in a suite of reproductive and non-reproductive traits. Both components explained relatively little of the phenotypic variance across traits. The dam component in our design contains variance caused by both maternal effects and dominance. If maternal effects are negligible as suggested by previous studies, our data suggest that dominance variance is an important source of variation in these traits. The lack of additive genetic variation, but possible existence of large amounts of non-additive genetic variation is consistent with the idea that female mate choice and multiple mating may be driven by differences in genetic compatibility between potential mates rather than by differences in genetic quality.
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molecular evidence of post copulatory inbreeding avoidance in the field cricket Gryllus bimaculatus
Proceedings of The Royal Society B: Biological Sciences, 2004Co-Authors: Amanda Bretman, Nina Wedell, Tom TregenzaAbstract:Female promiscuity has broad implications for individual behaviour, population genetics and even speciation. In the field cricket Gryllus bimaculatus, females will mate with almost any male presented to them, despite receiving no recorded direct benefits. Previous studies have shown that female crickets can benefit from polyandry through increased hatching success of their eggs. There is evidence that this effect is driven by the potential of polyandrous females to avoid fertilizing eggs with sperm from genetically incompatible males. We provide direct evidence supporting the hypothesis that polyandry is a mechanism to avoid genetic incompatibilities resulting from inbreeding. Using microsatellite markers we examined patterns of paternity in an experiment where each female mated with both a related and an unrelated male in either order. Overall, unrelated males were more successful in gaining paternity than were related males, but this effect was driven by a much greater success of unrelated males when they were the first to mate.
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Microsatellite loci for the field cricket, Gryllus bimaculatus and their cross-utility in other species of Orthoptera
Molecular Ecology Notes, 2003Co-Authors: Deborah A. Dawson, Amanda Bretman, Tom TregenzaAbstract:We have isolated 16 microsatellite loci in the field cricket, Gryllus bimaculatus . Nine loci were found to be polymorphic in G. bimaculatus and the number of alleles varied from seven to 14. All 16 loci were tested for amplification in nine other species. In the five species tested belonging to the same subfamily (Gryllinae), a minimum of nine loci amplified. These loci will be used to determine paternity as part of a study to investigate the genetic benefits of polyandry.
Klaus H. Hoffmann - One of the best experts on this subject based on the ideXlab platform.
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Activity, release and flow of digestive enzymes in the cricket, Gryllus bimaculatus
Physiological Entomology, 2007Co-Authors: Joseph Woodring, Klaus H. Hoffmann, Matthias W. LorenzAbstract:In the cricket Gryllus bimaculatus , proventricular pressure forces a nutri- ent fluid from the ground food-brei through a sieve at the base of the caecae, and the combination of secreted enzymes and water causes a rapid inflation of the caecae on the first day after imaginal ecdysis. The ceacal region of the midgut is the pri- mary site for the secretion of digestive enzymes. Proteases and amylase flow from the caecae into the mostly empty crop on day 1, and carbohydrate and protein diges- tion starts as soon as food is present (6 h). Thereafter, much of the amylase activity (but not protease) in the crop is synthesized and released by the crop tissues them- selves. Regurgitating proteases and amylases from the caecae into the crop after day 1 is most likely accomplished by temporarily halting proventricular peristalsis and allowing the caecal muscles to contract, forcing caecal contents, including enzymes, forward. The total activity of digestive enzymes in the caecae is virtually identical in 2-day-old fed and unfed females, indicating little or no secretagogue (prandial) regulation of enzyme secretion. Most of the digestive enzymes in the ventricular endoperitrophic space may originate from the mucus dragged from the caecae. Lipase activity is low in all gut regions in both starved and fed females. Head liga- tion or injection of trypsin modulating oostatic factor, allatostatin A or B fails to indicate any involvement of nerves or hormones in the release of digestive enzymes in the caecae. Gryllus bimaculatus appears to secrete digestive enzymes continuously, and a considerable loss of enzymes may occur at certain times through egestion.
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Inhibition of juvenile hormone biosynthesis in Gryllus bimaculatus by Glycosmis pentaphylla leaf compounds
Phytochemistry, 1999Co-Authors: Jayarama Muthukrishnan, Karlheinz Seifert, Klaus H. Hoffmann, Matthias W. LorenzAbstract:The EtOAc fraction of Glycosmis pentaphylla leaf extract inhibits the juvenile hormone III-biosynthesis in vitro of corpora allata from 3 day old females of the field cricket Gryllus bimaculatus. The bioactive compound which is responsible for this activity was identified as the quinazolone alkaloid arborine. This alkaloid showed also a larvicidal activity against the mosquito Culex quinquefasciatus.
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Ecdysteroid release by the prothoracic gland of Gryllus bimaculatus (Ensifera: Gryllidae) during larval–adult development
Journal of insect physiology, 1998Co-Authors: Uwe Oeh, Matthias W. Lorenz, Klaus H. HoffmannAbstract:Abstract The in vitro secretion of ecdysteroids from the prothoracic glands of larvae of Gryllus bimaculatus was analysed by HPLC-RIA. The primary product was identified as 3-dehydroecdysone (65–93%), with lesser amounts of ecdysone (7–35%). Production and release of ecdysteroids from the prothoracic glands are calcium-dependent. The rate of ecdysteroid release was low during the beginning and the end of the last two larval stages and high in between. Prothoracic glands from young adult females produced only minor amounts of ecdysteroids and ceased hormone production around day 4 after the moult.
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Ovarian Control of juvenile hormone-III biosynthesis in the cricket species Gryllus bimaculatus (Ensifera: Gryllidae)
Entomologia Generalis, 1996Co-Authors: Klaus H. Hoffmann, Matthias W. Lorenz, Paul Max KleinAbstract:Mature ovaries of Gryllus bimaculatus (De Geer 1773) exhibit various humoral factors which either stimulate or inhibit juvenile hormone-III biosynthesis in the corpora allata. Implantation of vitellogenic ovaries into adult MM of various age stimulates juvenile hormone biosynthesis within 24 h. Methanolic extracts inhibit juvenile hormone biosynthesis in active corpora allata in a short-term in vitro radiochemical assay. This inhibitory action is rapid, dose-dependent, and reversible.
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Vitellin and total protein degradation during embryogenesis in Gryllus bimaculatus de Geer (Ensifera, Gryllidae)
Invertebrate Reproduction & Development, 1994Co-Authors: Klaus H. Hoffmann, Verena WeishauptAbstract:Summary Two vitellins as well as other egg proteins of the cricket, Gryllus bimaculatus, are utilized progressively during embryonic development. The relative titer of each vitellin was determined as a function of development time using rocket immunoelectrophoresis with a specific anti-vitellin serum. The patterns of vitellins and other egg proteins differing in developmental time were demonstrated by SDS polyacrylamide gel electrophoresis.
