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Gerhard Gries - One of the best experts on this subject based on the ideXlab platform.
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How firebrats (Thysanura: Lepismatidae) detect and nutritionally benefit from their microbial symbionts Enterobacter cloacae and Mycotypha microspora.
Environmental entomology, 2013Co-Authors: Nathan Woodbury, Gerhard GriesAbstract:The phylogenetically ancient firebrats, Thermobia Domestica (Packard) (Thysanura: Lepismatidae), lack any form of long-distance communication, yet are able to locate mates in sustained hot and humid microhabitats, typically within human habitations where they feed on dried goods, including cellulosic substrates. We have recently shown that firebrats aggregate in response to two symbiotic microorganisms in their feces, the bacterium Enterobacter cloacae and the fungus Mycotypha microspora. Our objectives were to determine how firebrats detect M. microspora and E. cloacae, and whether these microbial symbionts nutritionally benefit firebrats. Applied to a glass surface in bioassays, E. cloacae as well as the isolated exopolysaccharide of E. cloacae induced arrestment of firebrats, whereas M. microspora induced arrestment only in the presence of cellulosic substrate. When M. microspora and E. cloacae were grown aerobically on cellulose agar, only M. microspora yielded zones of clearing indicative of enzymatic cellulose degradation. Firebrats also arrested in response to d-glucose, which is a constituent of the exopolysaccharide and which is produced by the cellulase of M. microspora during cellulose degradation. First- to third-instar nymphs of firebrats that were fed E. cloacae, M. microspora, or a nutrient-rich diet developed equally well. By consuming E. cloacae and M. microspora, and by spreading them through feces, firebrats appear able to occupy nutrient-poor habitats that otherwise would not support development of their offspring.
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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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Abiotic and Biotic Factors Affect Microhabitat Selection by the Firebrat, Thermobia Domestica (Packard) (Thysanura: Lepismatidae)
Journal of Insect Behavior, 2006Co-Authors: Michelle N. Tremblay, Gerhard GriesAbstract:Arthropod microhabitat selection involves a hierarchical assessment of abiotic and biotic factors. In choice experiments, we tested firebrat, Thermobia Domestica , microhabitat preferences. Firebrats preferred elevated (35°C) over ambient (20°C) temperature, black over white shelter, and small (1 cm) over large (15.5 cm) entrance holes. Food availability did not alter shelter selection by firebrats. Medium juveniles, large juveniles and adults, in homo- and heterogeneous populations, preferred high (4.5 and 6.0 mm) over low (1.5 and 3.0 mm) shelter heights. Small juveniles, however, selected shelters with conspecifics, not by size. Females held at 35°C, but not 20 or 25°C, laid large numbers of eggs. Thus, abiotic characteristics of a shelter, coupled with the presence of conspecifics, affect microhabitat selection by firebrats. These findings may improve entrapment and management systems of firebrats.
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.
Ashraf Ragab - One of the best experts on this subject based on the ideXlab platform.
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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, Colette 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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insemination eicosanoides et fecondite chez le lepisme Thermobia Domestica insecta thysanura
1991Co-Authors: Ashraf RagabAbstract:Chez l'insecte primitif, Thermobia Domestica, l'insemination est necessaire a la maturation complete des ovocytes vitellogeniques et a la ponte. Le travail presente etudie les implications des metabolites de l'acide arachidonique, en rapport avec l'insemination, sur la fecondite de cet insecte. L'appareil genital male presente une forte activite lipoxygenasique et ce systeme enzymatique est transfere du male a la femelle lors de l'accouplement. Apres insemination, l'activite d'une pla#2 s'accroit fortement dans le receptacle seminal de la femelle. Cette enzyme est calcium-dependante et libere l'acide arachidonique a partir des phospholipides. La stimulation de la pla#2 provoque l'hydrolyse des phosphatidylcholines. Cet acide gras est metabolise par les lipoxygenases apportees par le spermatophore; des etudes en cg-ms montrent que le 8-hete est le metabolite majeur forme. Ces resultats sont originaux pour les insectes, chez lesquels seules des prostaglandines ont ete identifiees. L'activite biologique des metabolites de l'acide arachidonique est etudiee chez la femelle, par application topique, soit d'eicosanoides, soit d'inhibiteurs specifiques. Les traitements avec des inhibiteurs irreversibles entrainent la sterilite du cycle reproducteur, ils empechent l'ovulation et l'oviposition. L'hypothese la plus plausible est que les eicosanoides formes dans le receptacle seminal agissent comme mediateur chimique local dans les regulations neurohormonales complexes conduisant a la ponte
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, Colette 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, Colette 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.
Thomas C. Kaufman - One of the best experts on this subject based on the ideXlab platform.
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expression patterns of the rogue hox genes hox3 zen and fushi tarazu in the apterygote insect Thermobia Domestica
Evolution & Development, 2004Co-Authors: Cynthia L Hughes, Paul Z Liu, Thomas C. KaufmanAbstract:Summary Many embryonic patterning genes are remarkably conserved between vertebrates and invertebrates, and the Hox genes are paradigmatic examples of this conservation. Yet even Hox genes can change dramatically in evolution. Two genes in particular—Hox3 and fushi tarazu—lost their ancestral roles as homeotic genes and play very different developmental roles in the fruit fly Drosophila melanogaster. The Drosophila Hox3 homologs zerknullt and bicoid act in extraembryonic tissues and in establishment of the anteroposterior axis, respectively, whereas fushi tarazu acts in segmentation and neurogenesis. It would be valuable to know what mechanisms allowed Hox3 and ftz to abandon their ancestral roles as homeotic genes and take on new roles. To explore the evolutionary transition of these genes, we analyzed their expression in a primitive insect, the firebrat Thermobia Domestica. The expression patterns seem to represent a stage of evolution intermediate between the ancestral state seen in basal arthropods and the derived expression patterns in Drosophila. These expression data help us to narrow the period in which the gene transitions took place. Hox3 appears to have evolved directly into zen within the insects, whereas ftz seems to have adopted the expression patterns of a segmentation and neurogenesis gene earlier in the mandibulate arthropods.
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The development and evolution of insect mouthparts as revealed by the expression patterns of gnathocephalic genes.
Evolution & development, 2002Co-Authors: Bryan T. Rogers, A Michael D. Peterson, Thomas C. KaufmanAbstract:To understand better both the development and evolution of insect mouthparts, we have compared the expression pattern of several developmentally important genes in insects with either mandibulate or stylate-haustellate mouthparts. Specifically, we examined the expression of the proboscipedia (pb) and Distal-less (Dll) gene products as well as three regulators of pb, Sex combs reduced (Scr), Deformed (Dfd), and cap 'n' collar (cnc). These genes are known to control the identity of cells in the gnathal segments of Drosophila melanogaster and would appear to have similar conserved functions in other insects. Together we have made an atlas of gene expression in the heads of three insects: Thermobia Domestica and Acheta Domestica, which likely exemplify the mandibulate mouthparts present in the common insect ancestor, and Oncopeltus fasciatus, which has piercing-sucking mouth parts that are typical of the Hemiptera. At the earliest stages of embryogenesis, only the expression of pb was found to differ dramatically between Oncopeltus and the other insects examined, although significant differences were observed later in development. This difference in pb expression reflects an apparent divergence in the specification of gnathal identity between mandibulate and stylate-haustellate mouthparts, which may result from a "phylogenetic homeosis" that occurred during the evolution of the Hemiptera.
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The embryonic expression pattern of labial, posterior homeotic complex genes and the teashirt homologue in an apterygote insect.
Development genes and evolution, 1999Co-Authors: Michael D. Peterson, Bryan T. Rogers, Aleksandar Popadic, Thomas C. KaufmanAbstract:During embryogenesis of the fruit fly, Drosophila melanogaster, the homeotic genes are required to specify proper cell fates along the anterior-posterior axis of the embryo. We cloned partial cDNAs of homologues of the Drosophila homeotic gene teashirt and five of the homeotic-complex (HOM-C) genes from the thysanuran insect, Thermobia Domestica, and assayed their embryonic expression patterns. The HOM-C genes we examined were labial, Antennapedia, Ultrabithorax, abdominal-A and Abdominal-B. As the expression pattern of these HOM-C genes is largely conserved among insects and as Thermobia is a member of a phylogenetically basal order of insects, we were able to infer their ancestral expression patterns in insects. We compare the expression patterns of the Thermobia HOM-C genes with their expression in Drosophila and other insects and discuss the potential roles these genes may have played in insect evolution. Interestingly, the teashirt homologue shows greater variability between Thermobia and Drosophila than any of the HOM-C genes. In particular, teashirt is not expressed strongly in the Thermobia abdomen, unlike Drosophila teashirt. We propose that teashirt expression has expanded posteriorly in Drosophila and contributed to a homogenization of the Drosophila larval thorax and abdomen.