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Gerhard Gries - One of the best experts on this subject based on the ideXlab platform.
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Fungal symbiont of firebrats (Thysanura) induces arrestment behaviour of firebrats and giant silverfish but not common silverfish
The Canadian Entomologist, 2013Co-Authors: Nathan Woodbury, Gerhard GriesAbstract:AbstractWe have recently shown that firebrats, Thermobia domestica (Packard) (Thysanura: Lepismatidae), carry, and deposit with their faeces, the symbiotic bacterium Enterobacter cloacae (Jordan 1890) Hormaeche and Edwards 1960 (Enterobacteriaceae) and the symbiotic fungus Mycotypha microspora Fenner, 1932 (Mycotyphaceae), and that these microbes induce arrestment behaviour and aggregation of firebrats. Here, we tested whether giant silverfish, Ctenolepisma longicaudata Escherich (Thysanura: Lepismatidae), and common silverfish, Lepisma saccharina (Linnaeus) (Thysanura: Lepismatidae), also arrest in response to these two microbes. In dual-choice bioassays, E. cloacae arrested firebrats but not giant silverfish or common silverfish, whereas M. microspora arrested firebrats and giant silverfish but not common silverfish. As close relatives, firebrats and giant silverfish have similar microclimate and nutrient requirements and may use M. microspora as the same aggregation cue when they aggregate in hot and humid microclimates where M. microspora proliferates and breaks down cellulose. As a more distant relative to firebrats and giant silverfish, common silverfish seem to require a different as yet unknown aggregation cue or signal, possibly one that is indicative of the type of microclimate (room temperature; high humidity) they prefer.
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Horizontal transmission of the microbial symbionts Enterobacter cloacae and Mycotypha microspora to their firebrat host
Entomologia Experimentalis et Applicata, 2013Co-Authors: Nathan Woodbury, Margo M. Moore, Gerhard GriesAbstract:The firebrat, Thermobia domestica (Packard) (Thysanura: Lepismatidae), aggregates in response to the faeces of conspecifics. This aggregation response is mediated by two microbial symbionts, the bacterium Enterobacter cloacae (Jordan) Hormaeche & Edwards (Enterobacteriaceae) and the fungus Mycotypha microspora Fenner (Mucorales). Our objective was to determine how these microbes are transmitted between firebrats. We produced fluorescently labelled E. cloacae and M. microspora and presented them to firebrats. Firebrats consumed large quantities of these labelled microbes and deposited them with their faeces where they proliferated rapidly. Firebrats did not harbour E. cloacae or M. microspora within their ovarioles or eggs, and thus cannot transmit them transovarially. Instead, firebrats acquired them horizontally whenever they fed on microbe-contaminated material, such as faeces, faeces-contaminated paper, or egg surfaces. Firebrats moult throughout their life, and with each moult they shed the cuticular lining of their digestive tract and likely any microbes residing therein. Because firebrats remain in close contact and live in groups of mixed age and gender, newly moulted individuals can readily re-acquire E. cloacae or M. microspora from group members. This ensures the perpetuation of their microbial aggregation and arrestment signal.
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Firebrats, Thermobia domestica, aggregate in response to the microbes Enterobacter cloacae and Mycotypha microspora
Entomologia Experimentalis et Applicata, 2013Co-Authors: Nathan Woodbury, Gerhard GriesAbstract:The firebrat, Thermobia domestica (Packard) (Thysanura: Lepismatidae), aggregates in response to the faeces of conspecifics as well as shelters previously inhabited by conspecifics. Our objective was to determine the source of the aggregation signal. Filter paper previously exposed to firebrats induced strong arrestment of firebrats. Polar solvents (water, methanol, acetonitrile) and less polar solvents (hexane, dichloromethane, ethyl ether), alone or in combination, failed to extract the aggregation signal from firebrat-exposed paper. Moreover, solvent-extracted paper continued to induce firebrat arrestment. In contrast, the aggregation signal could be obtained by physical extraction (freeze/thawing or ultrasonication) of firebrat-exposed paper submerged in water. Five fungal species and four bacterial species were isolated from ultrasonicant solutions on potato dextrose-, nutrient-, and GlcNAc-agar. Of the nine isolated microbes tested, only the fungus Mycotypha microspora Fenner (Mucorales) and the bacterium Enterobacter cloacae (Jordan) Hormaeche & Edwards (Enterobacteriaceae) induced arrestment of firebrats in bioassays. Our data support the conclusion that firebrats do not form aggregations in response to pheromones; instead, they aggregate in the presence of specific microbes or their metabolites.
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amber colored excreta a source of arrestment pheromone in firebrats Thermobia domestica
Entomologia Experimentalis Et Applicata, 2008Co-Authors: Nathan Woodbury, Gerhard GriesAbstract:Female, male, and juvenile firebrats, Thermobia domestica (Packard) (Thysanura: Lepismatidae), employ a pheromone that arrests conspecifics on contact. Paper shelters placed in a T. domestica colony accumulate fecal excreta (= frass) and other insect-derived debris. Such shelters elicit arrestment by conspecifics. However, the definitive source of the arrestment pheromone was not known. We tested the hypothesis that one or more debris components from a T. domestica shelter constitute the source of the arrestment pheromone. In dual-choice, still-air olfactometer experiments, scales, exuviae, antennae, caudal filaments, gregarine parasite cysts, and silk (each intact or macerated) retrieved from shelters and separated for experiments, as well as saliva, hemolymph, and fat body extracted from insects all failed to arrest female T. domestica. Similarly, paper that had been fed upon by insects did not elicit an arrestment response, eliminating insect-altered cellulose as the arrestant pheromone. In contrast, insect-exposed glass significantly arrested females. Moreover, females were significantly arrested by (i) loose, insect-derived debris brushed from shelters, (ii) a frass mixture manually separated from loose debris, and (iii) specific amber-type frass manually separated from the frass mixture. These results lead us to conclude that amber-type frass constitutes the source of at least part of the T. domestica arrestment pheromone.
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Amber‐colored excreta: a source of arrestment pheromone in firebrats, Thermobia domestica
Entomologia Experimentalis et Applicata, 2008Co-Authors: Nathan Woodbury, Gerhard GriesAbstract:Female, male, and juvenile firebrats, Thermobia domestica (Packard) (Thysanura: Lepismatidae), employ a pheromone that arrests conspecifics on contact. Paper shelters placed in a T. domestica colony accumulate fecal excreta (= frass) and other insect-derived debris. Such shelters elicit arrestment by conspecifics. However, the definitive source of the arrestment pheromone was not known. We tested the hypothesis that one or more debris components from a T. domestica shelter constitute the source of the arrestment pheromone. In dual-choice, still-air olfactometer experiments, scales, exuviae, antennae, caudal filaments, gregarine parasite cysts, and silk (each intact or macerated) retrieved from shelters and separated for experiments, as well as saliva, hemolymph, and fat body extracted from insects all failed to arrest female T. domestica. Similarly, paper that had been fed upon by insects did not elicit an arrestment response, eliminating insect-altered cellulose as the arrestant pheromone. In contrast, insect-exposed glass significantly arrested females. Moreover, females were significantly arrested by (i) loose, insect-derived debris brushed from shelters, (ii) a frass mixture manually separated from loose debris, and (iii) specific amber-type frass manually separated from the frass mixture. These results lead us to conclude that amber-type frass constitutes the source of at least part of the T. domestica arrestment pheromone.
Magdalena Maria Rost - One of the best experts on this subject based on the ideXlab platform.
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Comparative Studies on Regeneration of the Midgut Epithelium in Lepisma saccharina and Thermobia domestica
Annals of the Entomological Society of America, 2006Co-Authors: Magdalena Maria RostAbstract:Regeneration is a process of rebuilding damaged or disrupted cells and tissues. The insect's midgut epithelium becomes damaged by passage of the food mass and by secretory processes. The regeneration process occurs differently in two related species belonging to the primitive wingless insect group Zygentoma: Thermobia domestica (Packard) (Thysanura: Lepismatidae) and Lepisma saccharina L. (Thysanura: Lepismatidae). In T. domestica, the degenerated cells are replaced in a continuous manner by newly formed cells originating from regenerative cell groups. In L. saccharina, the midgut epithelium is totally removed and numerous regenerative cell groups form the new epithelium simultaneously in a cyclical manner. Regenerative cells, being responsible for all regenerative mechanisms, fulfill the role of primordial cells of the midgut epithelium. Here, I describe the process of degeneration and regeneration of the midgut epithelium in these two species at the transmission electron microscope level.
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Cellularization During Embryogenesis in Thermobia domestica (Zygentoma: Lepismatidae)
Annals of the Entomological Society of America, 2006Co-Authors: Magdalena Maria Rost, Izabela PoprawaAbstract:During the first day of embryogenesis in firebrat, Thermobia domestica (Packard) (Zygentoma: Lepismatidae), energids (nuclei surrounded by a thin layer of nonmembraned cytoplasm) migrate toward the periplasm. Some of them are dispersed in the periplasm, whereas others remain inside the yolk. As the first syncytial blastoderm is formed, the oolemma invaginates deeply into the yolk forming numerous folds. These folds surround the energids that are settled in the periplasm. The cellular blastoderm, formed at the end of cleavage, remains thin. These cellularization events are described at the ultrastructural level. Our previous studies dealt with midgut epithelium formation. Our current results indicate that the same mechanism of cellularization occurs in both processes in this primitive wingless insect. The similarities between the mode of cellularization of the blastoderm and the midgut epithelium are discussed.
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Primordial Germ Cell Differentiation in Natural and Manipulated Twin Embryos of Thermobia domestica (Insecta: Zygentoma)
Annals of the Entomological Society of America, 2005Co-Authors: Magdalena Maria Rost, Agnieszka Flakus, Jerzy KlagAbstract:In eggs of many insects there exists a characteristic structure called an oosom that is required for the formation and differentiation of primordial germ cells (PGCs). Thermobia domestica (Packard) belongs to the group of insects in which there are no visible signs of such germ cell determinants and PGCs are formed at the later stages of development. Spontaneous and experimental polyembryony helps to resolve the problem of germ cells determinants existence. The stratification of cytoplasmic inclusions in T. domestica eggs causes the displacement of germ cells determinants. As a result, all twin embryos and some single embryos (experimental polyembryony) have sterile gonads.
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Study of the Development of Natural and Manipulated Twin Embryos in Thermobia domestica (Thysanura: Lepismatidae)
Annals of the Entomological Society of America, 2004Co-Authors: Magdalena Maria RostAbstract:Centrifugation increases the frequency of twin formation during embryogenesis in firebrat, Thermobia domestica (Packard). Newly hatched eggs of T. domestica were separated into control and experimental centrifugal groups. Double embryos were found among both groups at ≈0.1% naturally and ≈4.5% after centrifugation. Embryos with a double head and a third eye were also observed among the centrifuged eggs. The development of morphological and anatomical structures of twin embryos was compared with those of single embryos. The analysis was carried out by using light and electron (scanning and transmission) microscopy. Embryonic twins may help explain the mechanisms that lead to formation of germ bands in short germ-band insects, a group to which T. domestica belongs.
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Ultrastructure of the Pleuropodium in 8-d-old Embryos of Thermobia domestica (Packard) (Insecta, Zygentoma)
Annals of the Entomological Society of America, 2004Co-Authors: Magdalena Maria Rost, Izabela Poprawa, Jerzy KlagAbstract:Pleuropodia of the invaginated type were observed on the first abdominal segment in 8-d-old embryos of Thermobia domestica (Packard). The pleuropodium is formed by a cytoplasmatic internal part and a mushroom-like cavity. The latter is filled with fluid and is composed of a stem protruding through the epidermis and a vesicle-like copula. The arrangement of membrane folds, mitochondria, and lipid drops was observed on electron micrographs (TEM) of pleuropodium cells. The position and structure of these organelles indicates that the cells of this organ perform transport and secretory functions.
Sarah M. Farris - One of the best experts on this subject based on the ideXlab platform.
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evolution from a
2014Co-Authors: Sarah M. FarrisAbstract:Developmental organization of the mushroom bodies of Thermobia domestica (Zygentoma, Lepismatidae): insights into mushroom bod
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Developmental organization of the mushroom bodies of Thermobia domestica (Zygentoma, Lepismatidae): insights into mushroom body evolution from a basal insect
Evolution & development, 2005Co-Authors: Sarah M. FarrisAbstract:The mushroom bodies of the insect brain are sensory integration centers best studied for their role in learning and memory. Studies of mushroom body structure and development in neopteran insects have revealed conserved morphogenetic mechanisms. The sequential production of morphologically distinct intrinsic neuron (Kenyon cell) subpopulations by mushroom body neuroblasts and the integration of newborn neurons via a discrete ingrowth tract results in an age-based organization of modular subunits in the primary output neuropil of the mushroom bodies, the lobes. To determine whether these may represent ancestral characteristics, the present account assesses mushroom body organization and development in the basal wingless insect Thermobia domestica. In this insect, a single calyx supplied by the progeny of two neuroblast clusters, and three perpendicularly oriented lobes are readily identifiable. The lobes are subdivided into 15 globular subdivisions (Trauben). Lifelong neurogenesis is observed, with axons of newborn Kenyon cells entering the lobes via an ingrowth core. The Trauben do not appear progressively during development, indicating that they do not represent the ramifications of sequentially produced subpopulations of Kenyon cells. Instead, a single Kenyon cell population produces highly branched axons that supply all lobe subdivisions. This suggests that although the ground plan for neopteran mushroom bodies existed in early insects, the organization of modular subunits composed of separate Kenyon cell subpopulations is a later innovation. Similarities between the calyx of Thermobia and the highly derived fruit fly Drosophila melanogaster also suggest a correlation between calyx morphology and Kenyon cell number.
Hugues Chap - One of the best experts on this subject based on the ideXlab platform.
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Inhibition of phospholipase A2 modulates fecundity in the primitive insect Thermobia domestica (Thysanura)
Journal of Insect Physiology, 1995Co-Authors: Colette Bitsch, A. Ragab, Hugues ChapAbstract:Abstract Phospholipase A 2 (PLA 2 ) activity was tested in the seminal receptacle of the firebrat female during an ovarian cycle and in relation to insemination. The PLA 2 activity was weak up to the time of insemination, while a strong increase of the enzyme activity occurred at the end of the ovarian cycle in both inseminated and non-inseminated females, indicating that PLA 2 is an endogenous enzyme not transferred by the spermatophore. Females received various drugs whose anti-PLA 2 effects were checked on the seminal receptacle tissues. The effects of the drugs were investigated on ovarian maturation and on the number of eggs layed by inseminated females. Dose-response relationships provide crucial indications that PLA 2 inhibition interferes with the firebrat fecundity. The emergent picture is that oocyte maturation is insensitive to PLA 2 activity, but that the treatments which reduce the release of arachidonic acid from cellular phospholipids interrupt some physiological link leading to egg deposition. The arachidonate metabolites are designated as the primer of the ovulation mechanisms; the possible role of development hormones in PLA 2 regulation is discussed.
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Phospholipase A2 activity in reproductive tissues of the firebrat Thermobia domestica (Insecta: Thysanura)
Insect Biochemistry and Molecular Biology, 1992Co-Authors: Ashraf Ragab, C. Bitsch, J.m.f. Ragab-thomas, A. Gassama-diagne, Hugues ChapAbstract:Abstract Upon in vitro incubation with [ 14 ]arachidonic acid, reproductive tissues of Thermobia domestica incorporated radioactivity, mostly into phospholipids. Stimulation with calcium ionophore A 23187 modified the distribution of the labeling between the various phospholipids, and promoted a release of arachidonic acid as well as metabolites comigrating with authentic HETEs. The lipolytic activity was tested against three exogenous phosphatidylcholines. It is concluded that arachidonic acid availability for eicosanoid biosynthesis is mostly regulated by a calcium-dependent phospholipase A 2 . The specific activity of PLA 2 was assayed in reproductive tissues. After insemination, the phospholipase activity strongly increased in the female seminal receptacle, but the rise was independent of the number of transfered spermatophores.
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The lipoxygenase pathway of arachidonic acid metabolism in reproductive tissues of the firebrat, Thermobia domestica (Thysanura)
Insect Biochemistry, 1991Co-Authors: A. Ragab, C. Bitsch, Hugues Chap, J. Durand, M. RigaudAbstract:Abstract The reproductive tissues of the primitive insect Thermobia domestica synthesize several eicosanoids when incubated with exogenous arachidonic acid. The enzymatic system was characterized with respect to kinetic parameters, Ca 2+ requirement and pH- and cofactor-dependence. Five monohydroxylated eicosatetraenoic acids (HETEs) were identified by mass spectrometry procedures, demonstrating the existence of the lipoxygenase pathway. Quantitative studies were performed by high-pressure liquid chromatography. It is confirmed that the 8-lipoxygenase activity remains the major pathway in tissues from males and from inseminated females. In female tissues, the amounts of metabolite depend on the number of spermatophores contained in the seminal receptacles. These data are in agreement with the hypothesis of a transfer of the enzyme from male to female during mating. The mechanisms involved are discussed in comparison with those of other insect species in which the synthesis of prostaglandins has been reported.
Nathan Woodbury - One of the best experts on this subject based on the ideXlab platform.
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Fungal symbiont of firebrats (Thysanura) induces arrestment behaviour of firebrats and giant silverfish but not common silverfish
The Canadian Entomologist, 2013Co-Authors: Nathan Woodbury, Gerhard GriesAbstract:AbstractWe have recently shown that firebrats, Thermobia domestica (Packard) (Thysanura: Lepismatidae), carry, and deposit with their faeces, the symbiotic bacterium Enterobacter cloacae (Jordan 1890) Hormaeche and Edwards 1960 (Enterobacteriaceae) and the symbiotic fungus Mycotypha microspora Fenner, 1932 (Mycotyphaceae), and that these microbes induce arrestment behaviour and aggregation of firebrats. Here, we tested whether giant silverfish, Ctenolepisma longicaudata Escherich (Thysanura: Lepismatidae), and common silverfish, Lepisma saccharina (Linnaeus) (Thysanura: Lepismatidae), also arrest in response to these two microbes. In dual-choice bioassays, E. cloacae arrested firebrats but not giant silverfish or common silverfish, whereas M. microspora arrested firebrats and giant silverfish but not common silverfish. As close relatives, firebrats and giant silverfish have similar microclimate and nutrient requirements and may use M. microspora as the same aggregation cue when they aggregate in hot and humid microclimates where M. microspora proliferates and breaks down cellulose. As a more distant relative to firebrats and giant silverfish, common silverfish seem to require a different as yet unknown aggregation cue or signal, possibly one that is indicative of the type of microclimate (room temperature; high humidity) they prefer.
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Horizontal transmission of the microbial symbionts Enterobacter cloacae and Mycotypha microspora to their firebrat host
Entomologia Experimentalis et Applicata, 2013Co-Authors: Nathan Woodbury, Margo M. Moore, Gerhard GriesAbstract:The firebrat, Thermobia domestica (Packard) (Thysanura: Lepismatidae), aggregates in response to the faeces of conspecifics. This aggregation response is mediated by two microbial symbionts, the bacterium Enterobacter cloacae (Jordan) Hormaeche & Edwards (Enterobacteriaceae) and the fungus Mycotypha microspora Fenner (Mucorales). Our objective was to determine how these microbes are transmitted between firebrats. We produced fluorescently labelled E. cloacae and M. microspora and presented them to firebrats. Firebrats consumed large quantities of these labelled microbes and deposited them with their faeces where they proliferated rapidly. Firebrats did not harbour E. cloacae or M. microspora within their ovarioles or eggs, and thus cannot transmit them transovarially. Instead, firebrats acquired them horizontally whenever they fed on microbe-contaminated material, such as faeces, faeces-contaminated paper, or egg surfaces. Firebrats moult throughout their life, and with each moult they shed the cuticular lining of their digestive tract and likely any microbes residing therein. Because firebrats remain in close contact and live in groups of mixed age and gender, newly moulted individuals can readily re-acquire E. cloacae or M. microspora from group members. This ensures the perpetuation of their microbial aggregation and arrestment signal.
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Firebrats, Thermobia domestica, aggregate in response to the microbes Enterobacter cloacae and Mycotypha microspora
Entomologia Experimentalis et Applicata, 2013Co-Authors: Nathan Woodbury, Gerhard GriesAbstract:The firebrat, Thermobia domestica (Packard) (Thysanura: Lepismatidae), aggregates in response to the faeces of conspecifics as well as shelters previously inhabited by conspecifics. Our objective was to determine the source of the aggregation signal. Filter paper previously exposed to firebrats induced strong arrestment of firebrats. Polar solvents (water, methanol, acetonitrile) and less polar solvents (hexane, dichloromethane, ethyl ether), alone or in combination, failed to extract the aggregation signal from firebrat-exposed paper. Moreover, solvent-extracted paper continued to induce firebrat arrestment. In contrast, the aggregation signal could be obtained by physical extraction (freeze/thawing or ultrasonication) of firebrat-exposed paper submerged in water. Five fungal species and four bacterial species were isolated from ultrasonicant solutions on potato dextrose-, nutrient-, and GlcNAc-agar. Of the nine isolated microbes tested, only the fungus Mycotypha microspora Fenner (Mucorales) and the bacterium Enterobacter cloacae (Jordan) Hormaeche & Edwards (Enterobacteriaceae) induced arrestment of firebrats in bioassays. Our data support the conclusion that firebrats do not form aggregations in response to pheromones; instead, they aggregate in the presence of specific microbes or their metabolites.
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amber colored excreta a source of arrestment pheromone in firebrats Thermobia domestica
Entomologia Experimentalis Et Applicata, 2008Co-Authors: Nathan Woodbury, Gerhard GriesAbstract:Female, male, and juvenile firebrats, Thermobia domestica (Packard) (Thysanura: Lepismatidae), employ a pheromone that arrests conspecifics on contact. Paper shelters placed in a T. domestica colony accumulate fecal excreta (= frass) and other insect-derived debris. Such shelters elicit arrestment by conspecifics. However, the definitive source of the arrestment pheromone was not known. We tested the hypothesis that one or more debris components from a T. domestica shelter constitute the source of the arrestment pheromone. In dual-choice, still-air olfactometer experiments, scales, exuviae, antennae, caudal filaments, gregarine parasite cysts, and silk (each intact or macerated) retrieved from shelters and separated for experiments, as well as saliva, hemolymph, and fat body extracted from insects all failed to arrest female T. domestica. Similarly, paper that had been fed upon by insects did not elicit an arrestment response, eliminating insect-altered cellulose as the arrestant pheromone. In contrast, insect-exposed glass significantly arrested females. Moreover, females were significantly arrested by (i) loose, insect-derived debris brushed from shelters, (ii) a frass mixture manually separated from loose debris, and (iii) specific amber-type frass manually separated from the frass mixture. These results lead us to conclude that amber-type frass constitutes the source of at least part of the T. domestica arrestment pheromone.
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Pheromone-based arrestment behaviour of three species of Thysanura (Lepismatidae)
2008Co-Authors: Nathan WoodburyAbstract:Aggregations of the common silverfish, Lepisma saccharina L., giant silverfish, Ctenolepisma longicaudata (Escherich), and firebrat, Thermobia domestica (Packard), are mediated by non-volatile, species-specific pheromones. In dual-choice olfactometer experiments, filter paper previously exposed to male, female, or juvenile L. saccharina or C. longicaudata arrested conspecifics regardless of developmental stage or gender. Lepisma saccharina did not respond to the C. longicaudata pheromone, nor to the T. domestica pheromone. However, C. longicaudata responded to the pheromones of both L. saccharina and T. domestica, whereas T. domestica responded to the C. longicaudata but not L. saccharina pheromone. Female T. domestica were significantly arrested by (i) loose, insect-derived debris brushed from shelters, (ii) a frass mixture manually separated from loose debris, and (iii) specific amber-type frass manually separated from the frass mixture, but did not respond to other types of shelter debris or insect-altered cellulose, suggesting that T. domestica pheromone is present in amber-type frass.
