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Richard Shine - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Wild Cane Toads (Rhinella marina) Expel Foreign Matter from the Coelom via the Urinary Bladder in Response to Internal Injury, Endoparasites and Disease
2016Co-Authors: Crystal Kelehear, Hugh I Jones, Benjamin A Wood, Richard ShineAbstract:Dissections of>1,200 wild-caught cane toads (Rhinella marina) in tropical Australia confirm a laboratory report that anurans can expel foreign objects from the Coelom by incorporating them into the urinary bladder. The foreign objects that we found inside bladders included a diverse array of items (e.g., grass seeds, twigs, insect prey, parasites), many of which may have entered the Coelom via rupture of the gut wall. In some cases, the urinary bladder was fused to other organs including liver, fat bodies, ovaries, Bidder’s organs, lungs, mesentery, stomach wall, gall bladder, and the abdominal wall. Acanthocephalan parasites (of a range of developmental stages) were identified from the walls of the urinary bladders of three cane toads. This organ may play a significant role in destroying or excreting metazoan parasites, as well as inanimate objects
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wild cane toads rhinella marina expel foreign matter from the Coelom via the urinary bladder in response to internal injury endoparasites and disease
PLOS ONE, 2015Co-Authors: Crystal Kelehear, Hugh I Jones, Benjamin A Wood, Richard ShineAbstract:Dissections of >1,200 wild-caught cane toads (Rhinella marina) in tropical Australia confirm a laboratory report that anurans can expel foreign objects from the Coelom by incorporating them into the urinary bladder. The foreign objects that we found inside bladders included a diverse array of items (e.g., grass seeds, twigs, insect prey, parasites), many of which may have entered the Coelom via rupture of the gut wall. In some cases, the urinary bladder was fused to other organs including liver, fat bodies, ovaries, Bidder’s organs, lungs, mesentery, stomach wall, gall bladder, and the abdominal wall. Acanthocephalan parasites (of a range of developmental stages) were identified from the walls of the urinary bladders of three cane toads. This organ may play a significant role in destroying or excreting metazoan parasites, as well as inanimate objects.
Crystal Kelehear - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Wild Cane Toads (Rhinella marina) Expel Foreign Matter from the Coelom via the Urinary Bladder in Response to Internal Injury, Endoparasites and Disease
2016Co-Authors: Crystal Kelehear, Hugh I Jones, Benjamin A Wood, Richard ShineAbstract:Dissections of>1,200 wild-caught cane toads (Rhinella marina) in tropical Australia confirm a laboratory report that anurans can expel foreign objects from the Coelom by incorporating them into the urinary bladder. The foreign objects that we found inside bladders included a diverse array of items (e.g., grass seeds, twigs, insect prey, parasites), many of which may have entered the Coelom via rupture of the gut wall. In some cases, the urinary bladder was fused to other organs including liver, fat bodies, ovaries, Bidder’s organs, lungs, mesentery, stomach wall, gall bladder, and the abdominal wall. Acanthocephalan parasites (of a range of developmental stages) were identified from the walls of the urinary bladders of three cane toads. This organ may play a significant role in destroying or excreting metazoan parasites, as well as inanimate objects
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wild cane toads rhinella marina expel foreign matter from the Coelom via the urinary bladder in response to internal injury endoparasites and disease
PLOS ONE, 2015Co-Authors: Crystal Kelehear, Hugh I Jones, Benjamin A Wood, Richard ShineAbstract:Dissections of >1,200 wild-caught cane toads (Rhinella marina) in tropical Australia confirm a laboratory report that anurans can expel foreign objects from the Coelom by incorporating them into the urinary bladder. The foreign objects that we found inside bladders included a diverse array of items (e.g., grass seeds, twigs, insect prey, parasites), many of which may have entered the Coelom via rupture of the gut wall. In some cases, the urinary bladder was fused to other organs including liver, fat bodies, ovaries, Bidder’s organs, lungs, mesentery, stomach wall, gall bladder, and the abdominal wall. Acanthocephalan parasites (of a range of developmental stages) were identified from the walls of the urinary bladders of three cane toads. This organ may play a significant role in destroying or excreting metazoan parasites, as well as inanimate objects.
Valerie B. Morris - One of the best experts on this subject based on the ideXlab platform.
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Analysis of Coelom development in the sea urchin Holopneustes purpurescens yielding a deuterostome body plan.
Biology open, 2016Co-Authors: Valerie B. MorrisAbstract:An analysis of early Coelom development in the echinoid Holopneustes purpurescens yields a deuterostome body plan that explains the disparity between the pentameral plan of echinoderms and the bilateral plans of chordates and hemichordates, the three major phyla of the monophyletic deuterostomes. The analysis shows an early separation into a medial hydrocoele and lateral Coelomic mesoderm with an enteric channel between them before the hydrocoele forms the pentameral plan of five primary podia. The deuterostome body plan thus has a single axial or medial Coelom and a pair of lateral Coeloms, all surrounding an enteric channel, the gut channel. Applied to the phyla, the medial Coelom is the hydrocoele in echinoderms, the notochord in chordates and the proboscis Coelom in hemichordates: the lateral Coeloms are the Coelomic mesoderm in echinoderms, the paraxial mesoderm in chordates and the lateral Coeloms in hemichordates. The plan fits frog and chick development and the echinoderm fossil record, and predicts genes involved in Coelomogenesis as the source of deuterostome macroevolution.
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Coelomogenesis during the abbreviated development of the echinoid Heliocidaris erythrogramma and the developmental origin of the echinoderm pentameral body plan.
Evolution & development, 2011Co-Authors: Valerie B. MorrisAbstract:SUMMARY The development of the Coeloms is described in an echinoid with an abbreviated larval development and shows the early morphogenesis of the Coeloms of the adult stage. The development is described from images obtained by laser scanning confocal microscopy. The development in Heliocidaris erythrogramma is asymmetric with a larger left Coelom forming on the larval-left side and a smaller right Coelom forming on the larval-right side. The right Coelom forms after the development of the left Coelom is well advanced. The hydrocoele forms from the anterior part of the left Coelom. The five lobes of the hydrocoele from which the pentamery of the adult derives take shape on the outer, distal wall of the anterior part of the left Coelom. The hydrocoele separates from the more posterior part of the left Coelom, which becomes the left posterior Coelom. The lobes of the hydrocoele are named, based on the site of the connexion of the stone canal to the hydrocoele. The mouth is assumed to form by penetration through only the outer, distal wall of the hydrocoele and the ectoderm. Both larval and adult polarities are evident in this larva. A comparison with Coelomogenesis in the asteroid Parvulastra exigua, which also has an abbreviated development, leads to predictions of homology between the echinoderm and chordate phyla that do not require the hypothesis of a dorsoventral inversion event in chordates.
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The Coeloms in a late brachiolaria larva of the asterinid sea star Parvulastra exigua: deriving an asteroid Coelomic model
Acta Zoologica, 2010Co-Authors: Valerie B. Morris, Paulina Selvakumaraswamy, Renee Whan, Maria ByrneAbstract:Morris, V.B., Selvakumaraswamy, P., Whan, R., and Byrne, M. 2011. The Coeloms in a late brachiolaria larva of the asterinid sea star Parvulastra exigua: deriving an asteroid Coelomic model. —Acta Zoologica (Stockholm) 92: 266–275. The Coeloms and their interconnexions in a late pre-metamorphic brachiolaria larva of a sea star are described from the series of images in the frontal, transverse and sagittal planes obtained by confocal laser scanning microscopy. A larval, brachial Coelom connects with the Coeloms of the adult rudiment that lie posteriorly. The connexion is through the anterior Coelom, which lies over the head of the archenteron, to the right anterior Coelom and then to the left posterior Coelom through the ventral horn of the left posterior Coelom. The right posterior Coelom is a separate Coelom. The hydrocoele is on the larval left side separated from other Coeloms except for a connexion to the anterior Coelom. On the larval right side, the anterior Coelom and right anterior Coelom connect with the pore canal that opens to the exterior at the hydropore. From these Coeloms, we derived an asteroid Coelomic model comprising the larval left and right Coeloms linked over the head of the archenteron by a common anterior Coelom. The asymmetry of the hydrocoele and the left posterior Coelom on the left side linked through the common anterior Coelom to the right side, with the external opening, translates into the oral and aboral Coeloms of the adult stage. The Coelomic model has application in the search for morphological homology between the echinoderm classes and the deuterostome phyla.
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Development of the five primary podia from the Coeloms of a sea star larva: homology with the echinoid echinoderms and other deuterostomes
Proceedings. Biological sciences, 2009Co-Authors: Valerie B. Morris, Paulina Selvakumaraswamy, Renee Whan, Maria ByrneAbstract:Confocal laser scanning microscopy of larvae of the asteroid Parvulastra exigua was used to investigate the development of the five primary podia from the Coeloms in the echinoderm phylum in an approach to the problem of morphological homology in the deuterostome phyla. The development is shown from an early brachiolaria larval stage to a pre-settlement late brachiolaria larval stage. In the early brachiolaria larva, a single enterocoele connected to the archenteron has formed into two lateral Coeloms and an anterior Coelom. The primary podia form from the Coelomic regions on the left side of the brachiolaria larva, while on the right the Coelomic regions connect with the exterior through the pore canal and hydropore. The anterior Coelom forms the Coelom of the brachia. Homology between the primary podia of the asteroid and the echinoid classes of echinoderms is described and extended to Coeloms of other deuterostome phyla.
Rudolf A. Raff - One of the best experts on this subject based on the ideXlab platform.
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Morphogenetic mechanisms of Coelom formation in the direct-developing sea urchin Heliocidaris erythrogramma
Development Genes and Evolution, 2009Co-Authors: Margaret S. Smith, Steve Collins, Rudolf A. RaffAbstract:Indirect development via a feeding pluteus larva represents the ancestral mode of sea urchin development. However, some sea urchin species exhibit a derived form of development, called direct development, in which features of the feeding larva are replaced by accelerated development of the adult. A major difference between these two developmental modes is the timing of the formation of the left Coelom and initiation of adult development. These processes occur much earlier in developmental and absolute time in direct developers and may be underlain by changes in morphogenetic processes. In this study, we explore whether differences in the cellular mechanisms responsible for the development of the left Coelom and adult structures are associated with the change in the timing of their formation in the direct-developing sea urchin Heliocidaris erythrogramma . We present evidence that left Coelom formation in H. erythrogramma , which differs in major aspects of Coelom formation in indirect developers, is not a result of cell division. Further, we demonstrate that subsequent development of adult structures requires cell division.
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From larval bodies to adult body plans: patterning the development of the presumptive adult ectoderm in the sea urchin larva
Development Genes and Evolution, 2005Co-Authors: Sharon B. Minsuk, Mary E. Andrews, Rudolf A. RaffAbstract:Echinoderms are unique among bilaterians for their derived, nonbilateral adult body plan. Their radial symmetry emerges from the bilateral larval body plan by the establishment of a new axis, the adult oral–aboral axis, involving local mesoderm–ectoderm interactions. We examine the mechanisms underlying this transition in the direct-developing sea urchin Heliocidaris erythrogramma . Adult ectoderm arises from vestibular ectoderm in the left vegetal quadrant. Inductive signals from the left Coelom are required for adult ectodermal development but not for initial vestibule formation. We surgically removed gastrula archenteron, making whole-ectoderm explants, left-, right-, and animal-half ectoderm explants, and recombinants of these explants with left Coelom. Vestibule formation was analyzed morphologically and with radioactive in situ hybridization with HeET-1 , an ectodermal marker. Whole ectodermal explants in the absence of Coelom developed vestibules on the left side or ventrally but not on the right side, indicating that left–right polarity is ectoderm autonomous by the gastrula stage. However, right-half ectodermal explants robustly formed vestibules that went on to form adult structures when recombined with the left Coelom, indicating that the right side retains vestibule-forming potential that is normally suppressed by signals from the left-side ectoderm. Animal-half explants formed vestibules only about half the time, demonstrating that animal–vegetal axis determination occurs earlier. However, when combined with the left Coelom, animal-half ectoderm always formed a vestibule, indicating that the left Coelom can induce vestibule formation. This suggests that although Coelomic signals are not required for vestibule formation, they may play a role in coordinating the Coelom–vestibule interaction that establishes the adult oral–aboral axis.
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Pattern formation in a pentameral animal: induction of early adult rudiment development in sea urchins.
Developmental Biology, 2002Co-Authors: Sharon B. Minsuk, Rudolf A. RaffAbstract:We investigated adult rudiment induction in the direct-developing sea urchin Heliocidaris erythrogramma microsurgically. After removal of the archenteron (which includes presumptive Coelomic mesoderm as well as presumptive endoderm) from late gastrulae, larval ectoderm develops properly but obvious rudiments (tube feet, nervous system, and adult skeleton) fail to form, indicating that Coelomic mesoderm, endoderm, or both are required for induction of adult development. Recombination of ectoderm and archenteron rescues development. Implanted endoderm alone or left Coelom alone each regenerate the full complement of archenteron derivatives; thus, they are uninformative as to the relative inductive potential of the two regions. However, in isolated ectoderm, more limited regeneration gives rise to larvae containing no archenteron derivatives at all, endoderm only, or both endoderm and left Coelom. Adult nervous system begins to develop only in the latter, indicating that left Coelom is required for the inductive signal. Isolated ectoderm develops a vestibule (the precursor of adult ectoderm) and correctly regulates vestibular expression of the ectodermal territory marker HeET-1, indicating that the early phase of vestibule development occurs autonomously; only later development requires the inductive signal. Another ectodermal marker, HeARS, is regulated properly in the larval ectoderm region, but not in the vestibule. HeARS regulation thus represents an early response to the inducing signal. We compare HeARS expression in H. erythrogramma with that in indirect developers and discuss its implications for modularity in the evolution of developmental mode.
A S Maiorova - One of the best experts on this subject based on the ideXlab platform.
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the microscopic anatomy and ultrastructure of the contractile vessel in the sipunculan themiste hexadactyla sato 1930 sipuncula sipunculidea
Russian Journal of Marine Biology, 2014Co-Authors: A S Maiorova, Andrey V. AdrianovAbstract:The microscopic anatomy and ultrastructure of the contractile vessel of the sipunculan Themiste hexadactyla (Sato, 1930) from Vostok Bay (the Sea of Japan) were studied by histological and electron microscope methods. The ultrastructural features of the internal (endothelium) and external (coelothelium) lining of the contractile vessel are described and illustrated. Numerous macromolecular filters, the so-called “double diaphragms,” were found in the external coelothelium facing the cavity of the trunk Coelom. This suggests a possible filtration from the tentacular Coelom into the trunk Coelom though the contractile vessel wall. The microscopic peculiarities of the main tube of the contractile vessel and its numerous lateral branches twining around several internal organs are described in detail. The contractile vessel is polyfunctional: it can act as the main reservoir for the cavity fluid during the withdrawal of the tentacular crown and performs the functions of the distribution system in sipunculans.
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Ultrastructure of the Coelomocytes in the Tentacular Coelom of Thysanocardia nigra Ikeda, 1904 (Sipuncula)
Russian Journal of Marine Biology, 2003Co-Authors: A S Maiorova, Andrey V. AdrianovAbstract:Free-floating Coelomocytes in the tentacular Coelomic cavity of the sipunculan Thysanocardia nigra Ikeda, 1904, were studied using light interference contrast microscopy and scanning and transmission electron microscopy. The following Coelomocyte types were distinguished: hemerythrocytes, amoebocytes, and two morphological types of granular cells. No clusters of specialized cells that had been reported to occur in the trunk Coelom of Th. nigra were found in the tentacular Coelom. The corresponding types of Coelomocytes from the tentacular and trunk Coelomic cavities were shown to differ in size. These two Coeloms are completely separated in sipunculans.
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Free-swimming Cellular Complexes in the Coelom of the Sipunculid Thysanocardia nigra Ikeda, 1904 (Sipuncula)
Russian Journal of Marine Biology, 2003Co-Authors: A S Maiorova, Andrey V. AdrianovAbstract:The ultrastructural characteristics of Coelomic cell complexes in the Coelomic fluid were investigated with the use of transmission electron microscopy on the example of Japanese sipunculid. In the sipunculid Coelom, complexes consisting of several cells were found for the first time: the central glandular cell and the outer layer of podocytes. Peculiar cell complexes (“urns”), comprising by ciliary and granular cells, were described in Thysanocardia for the first time. It had been proposed that both types of Coelomic cell complexes dissociated from extensive chloragogenic tissue clusters on the intestine surface of Th. nigra. The variety of cell complexes in the Coelom of other sipunculid is discussed.
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Microscopic anatomy and ultrastructure of a Polian vessel in the sipunculan Thysanocardia nigra Ikeda, 1904 from the Sea of Japan
Russian Journal of Marine Biology, 2002Co-Authors: Andrey V. Adrianov, A S MaiorovaAbstract:The microscopic anatomy and ultrastructure of a Polian vessel have been studied in the sipunculan Thysanocardia nigra Ikeda, 1904 from the Sea of Japan using the methods of histology and electron microscopy. We describe ultrastructural features of the inner and outer coelothelium, which is constructed of podocytes and multiciliary cells. Between the processes of the podocyte cells, we found double diaphragms that are considered characteristic macromolecular filters. We conclude from an analysis of the ultrastructural features of the vessel wall that Coelomic fluid may be filtered from the tentacular Coelom to the trunk Coelom via the wall of the Polian vessel.