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Szczepan M. Bilinski - One of the best experts on this subject based on the ideXlab platform.

  • Excretion in the mother’s body: modifications of the larval Excretory System in the viviparous dermapteran, Arixenia esau
    Protoplasma, 2018
    Co-Authors: Mariusz K. Jaglarz, Waclaw Tworzydlo, Szczepan M. Bilinski
    Abstract:

    The vast majority of Dermaptera are free-living and oviparous, i.e., females lay eggs within which embryonic development occurs until the larva hatches. In contrast, in the epizoic dermapteran Arixenia esau, eggs are retained within mother's body and the embryos and first instar larvae develop inside her reproductive System. Such a reproductive strategy poses many physiological challenges for a mother, one of which is the removal of metabolic waste generated by the developing offspring. Here, we examine how the Arixenia females cope with this challenge by analyzing features of the developing larval Excretory System. Our comparative analyses of the early and late first instar larvae revealed characteristic modifications in the cellular architecture of the Malpighian tubules, indicating that these organs are functional. The results of the electron probe microanalyses suggest additionally that the larval Malpighian tubules are mainly involved in maintaining ion homeostasis. We also found that the lumen of the larval alimentary track is occluded by a cellular diaphragm at the midgut-hindgut junction and that cells of the diaphragm accumulate metabolic compounds. Such an organization of the larval gut apparently prevents fouling of the mother's organism with the offspring metabolic waste and therefore can be regarded as an adaptation for viviparity.

  • excretion in the mother s body modifications of the larval Excretory System in the viviparous dermapteran arixenia esau
    Protoplasma, 2018
    Co-Authors: Mariusz K. Jaglarz, Waclaw Tworzydlo, Szczepan M. Bilinski
    Abstract:

    The vast majority of Dermaptera are free-living and oviparous, i.e., females lay eggs within which embryonic development occurs until the larva hatches. In contrast, in the epizoic dermapteran Arixenia esau, eggs are retained within mother's body and the embryos and first instar larvae develop inside her reproductive System. Such a reproductive strategy poses many physiological challenges for a mother, one of which is the removal of metabolic waste generated by the developing offspring. Here, we examine how the Arixenia females cope with this challenge by analyzing features of the developing larval Excretory System. Our comparative analyses of the early and late first instar larvae revealed characteristic modifications in the cellular architecture of the Malpighian tubules, indicating that these organs are functional. The results of the electron probe microanalyses suggest additionally that the larval Malpighian tubules are mainly involved in maintaining ion homeostasis. We also found that the lumen of the larval alimentary track is occluded by a cellular diaphragm at the midgut-hindgut junction and that cells of the diaphragm accumulate metabolic compounds. Such an organization of the larval gut apparently prevents fouling of the mother's organism with the offspring metabolic waste and therefore can be regarded as an adaptation for viviparity.

Insa Bonow - One of the best experts on this subject based on the ideXlab platform.

  • Ultrastructure study of the Excretory System and the genital primordium of the infective stage ofOnchocerca volvulus (Nematoda:Filarioidea)
    Parasitology Research, 1995
    Co-Authors: G. Strote, Insa Bonow
    Abstract:

    The electron microscopic investigation of the anterior part of the infective third-stage juvenile of Onchocerca volvulus provides first insights into the structure of the Excretory System of this developmental stage of the parasite. The most anterior part of this System consists of a cell process of the syncytial Excretory cells. At this height the Excretory cells enclose the cuticle-lined Excretory channel. The channel is in the process of elongation in the anterior-posterior direction, indicated by cell division in this region. More posteriad an ampulla-like structure is forming in the cytoplasm of the Excretory cells. The inner surface of this ampulla is lined with a small number of single microvilli. In this part of the System the cytoplasm of the Excretory cells is rich in Golgi bodies and endocytic vesicles. The ampulla has direct access to the exterior by the Excretory duct. The Excretory duct is a cuticle-lined structure surrounded by supporting fibres of an additional cell. This duct cell connects the Excretory duct to the body-wall cuticle at the Excretory pore. Adjacent to the region of the Excretory System a cell is found that resembles a gland cell. This cell is in close contact to the ventral nerve cord. The genital primordia of the third-stage juvenile consist of several dividing cells. The female genital primordium is seen at the junction of the muscular with the glandular oesophagus and the male primordium can be found at the junction of the glandular oesophagus with the gut.

  • Ultrastructure study of the Excretory System and the genital primordium of the infective stage of Onchocerca volvulus (Nematoda:Filarioidea).
    Parasitology research, 1995
    Co-Authors: G. Strote, Insa Bonow
    Abstract:

    The electron microscopic investigation of the anterior part of the infective third-stage juvenile ofOnchocerca volvulus provides first insights into the structure of the Excretory System of this developmental stage of the parasite. The most anterior part of this System consists of a cell process of the syncytial Excretory cells. At this height the Excretory cells enclose the cuticle-lined Excretory channel. The channel is in the process of elongation in the anterior-posterior direction, indicated by cell division in this region. More posteriad an ampulla-like structure is forming in the cytoplasm of the Excretory cells. The inner surface of this ampulla is lined with a small number of single microvilli. In this part of the System the cytoplasm of the Excretory cells is rich in Golgi bodies and endocytic vesicles. The ampulla has direct access to the exterior by the Excretory duct. The Excretory duct is a cuticle-lined structure surrounded by supporting fibres of an additional cell. This duct cell connects the Excretory duct to the body-wall cuticle at the Excretory pore. Adjacent to the region of the Excretory System a cell is found that resembles a gland cell. This cell is in close contact to the ventral nerve cord. The genital primordia of the third-stage juvenile consist of several dividing cells. The female genital primordium is seen at the junction of the muscular with the glandular oesophagus and the male primordium can be found at the junction of the glandular oesophagus with the gut.

J Thornhill - One of the best experts on this subject based on the ideXlab platform.

  • The schistosome Excretory System: a key to regulation of metabolism, drug excretion and host interaction
    Trends in parasitology, 2009
    Co-Authors: John R. Kusel, Paul Mcveigh, J Thornhill
    Abstract:

    There is a gulf between the enormous information content of the various genome projects and the understanding of the life of the parasite in the host. In vitro studies with adult Schistosoma mansoni using several substrates suggest that the Excretory System contains both P-glycoproteins and multiresistance proteins. If both these families of protein were active in vivo, they could regulate parasite metabolism and be responsible for the excretion of drugs. During skin penetration, membrane-impermeant molecules of a wide range of molecular weights can be taken into the cercaria and schistosomulum through the nephridiopore, through the surface membrane or through both. We speculate that this uptake process might stimulate novel signalling pathways involved in growth and development.

  • Excretion of fluorescent substrates of mammalian multidrug resistance-associated protein (MRP) in the Schistosoma mansoni Excretory System
    Parasitology, 2004
    Co-Authors: Hiroshi Sato, John R. Kusel, J Thornhill
    Abstract:

    The protonephridium of platyhelminths including Schistosoma mansoni plays a pivotal role in their survival by excretion of metabolic wastes as well as xenobiotics, and can be revealed in the living adult parasite by certain fluorescent compounds which are concentrated in Excretory tubules and collecting ducts. To determine the presence of the multidrug resistance-associated protein (MRP) as a possible transporter in protonephridial epithelium, adult schistosomes were exposed to a fluorescent Ca 2+ indicator, fluo-3 acetyloxymethyl ester, which is a potential substrate of mammalian MRP. Specific fluorescence related to fluo-3/Ca 2+ chelate delineated the whole length of the protonephridial System. Simultaneously, a fluorescent substance was accumulated in the posterior part of collecting ducts and the Excretory bladder. Similarly, when other fluorogenic substrates for mammalian MRP such as monoclorobimane, fluorescein diacetate, and 5(6)-carboxyfluorescein diacetate were applied to adult schistosomes, these fluorescent markers were observed in the Excretory tubules through to the Excretory bladder. The Excretory System of mechanically-transformed schistosomula was not labelled with any of these 4 fluorescent markers. These findings suggest that the protonephridial epithelium of adult schistosomes, but not schistosomula, might express the homologue of the mammalian MRP transporting organic anionic conjugates with glutathione, glucuronate or sulphate as well as unconjugated amphiphilic organic anions.

  • Functional visualization of the Excretory System of adult Schistosoma mansoni by the fluorescent marker resorufin.
    Parasitology, 2002
    Co-Authors: H Sato, J R Kusel, J Thornhill
    Abstract:

    Excretion of metabolic wastes as well as xenobiotics is a major concern of all living organisms, and the Platyhelminthes including Schistosoma mansoni possess the protonephridial Excretory System for their survival. Except for some ultra-structural and biochemical information, little is known about the protonephridium of platyhelminths due to a lack of established techniques for exploring the Excretory activity. This study describes a new technique to assess the Excretory activity of S. mansoni by use of the fluorescent marker resorufin, which is a potential substrate of the drug efflux pump, P-glycoprotein. After simple diffusion into the schistosome body, fluorescent resorufin was concentrated in the Excretory tubules by an energy-dependent mechanism and excreted via the nephridiopore. The present technique of labelling functionally the Excretory System was applicable to adult worms, but not schistosomula or cercariae. A variety of modulators known to interfere with mammalian P-glycoprotein function perturbed resorufin excretion from male adult schistosomes, including cyclosporin A, Ro11-2933, verapamil, or nifedipine. This technique of labelling the Excretory System with fluorescent resorufin has enabled us to study aspects of the physiological function, hitherto unknown, of the protonephridial System of S. mansoni.

Mariusz K. Jaglarz - One of the best experts on this subject based on the ideXlab platform.

  • Excretion in the mother’s body: modifications of the larval Excretory System in the viviparous dermapteran, Arixenia esau
    Protoplasma, 2018
    Co-Authors: Mariusz K. Jaglarz, Waclaw Tworzydlo, Szczepan M. Bilinski
    Abstract:

    The vast majority of Dermaptera are free-living and oviparous, i.e., females lay eggs within which embryonic development occurs until the larva hatches. In contrast, in the epizoic dermapteran Arixenia esau, eggs are retained within mother's body and the embryos and first instar larvae develop inside her reproductive System. Such a reproductive strategy poses many physiological challenges for a mother, one of which is the removal of metabolic waste generated by the developing offspring. Here, we examine how the Arixenia females cope with this challenge by analyzing features of the developing larval Excretory System. Our comparative analyses of the early and late first instar larvae revealed characteristic modifications in the cellular architecture of the Malpighian tubules, indicating that these organs are functional. The results of the electron probe microanalyses suggest additionally that the larval Malpighian tubules are mainly involved in maintaining ion homeostasis. We also found that the lumen of the larval alimentary track is occluded by a cellular diaphragm at the midgut-hindgut junction and that cells of the diaphragm accumulate metabolic compounds. Such an organization of the larval gut apparently prevents fouling of the mother's organism with the offspring metabolic waste and therefore can be regarded as an adaptation for viviparity.

  • excretion in the mother s body modifications of the larval Excretory System in the viviparous dermapteran arixenia esau
    Protoplasma, 2018
    Co-Authors: Mariusz K. Jaglarz, Waclaw Tworzydlo, Szczepan M. Bilinski
    Abstract:

    The vast majority of Dermaptera are free-living and oviparous, i.e., females lay eggs within which embryonic development occurs until the larva hatches. In contrast, in the epizoic dermapteran Arixenia esau, eggs are retained within mother's body and the embryos and first instar larvae develop inside her reproductive System. Such a reproductive strategy poses many physiological challenges for a mother, one of which is the removal of metabolic waste generated by the developing offspring. Here, we examine how the Arixenia females cope with this challenge by analyzing features of the developing larval Excretory System. Our comparative analyses of the early and late first instar larvae revealed characteristic modifications in the cellular architecture of the Malpighian tubules, indicating that these organs are functional. The results of the electron probe microanalyses suggest additionally that the larval Malpighian tubules are mainly involved in maintaining ion homeostasis. We also found that the lumen of the larval alimentary track is occluded by a cellular diaphragm at the midgut-hindgut junction and that cells of the diaphragm accumulate metabolic compounds. Such an organization of the larval gut apparently prevents fouling of the mother's organism with the offspring metabolic waste and therefore can be regarded as an adaptation for viviparity.

Peter W Reddien - One of the best experts on this subject based on the ideXlab platform.

  • a regulatory program for Excretory System regeneration in planarians
    Development, 2011
    Co-Authors: Lucila M Scimone, Mansi Srivastava, George W Bell, Peter W Reddien
    Abstract:

    Planarians can regenerate any missing body part, requiring mechanisms for the production of organ Systems in the adult, including their prominent tubule-based filtration Excretory System called protonephridia. Here, we identify a set of genes, Six1/2-2, POU2/3, hunchback, Eya and Sall, that encode transcription regulatory proteins that are required for planarian protonephridia regeneration. During regeneration, planarian stem cells are induced to form a cell population in regeneration blastemas expressing Six1/2-2, POU2/3, Eya, Sall and Osr that is required for Excretory System formation. POU2/3 and Six1/2-2 are essential for these precursor cells to form. Eya, Six1/2-2, Sall, Osr and POU2/3-related genes are required for vertebrate kidney development. We determined that planarian and vertebrate Excretory cells express homologous proteins involved in reabsorption and waste modification. Furthermore, we identified novel nephridia genes. Our results identify a transcriptional program and cellular mechanisms for the regeneration of an Excretory organ and suggest that metazoan Excretory Systems are regulated by genetic programs that share a common evolutionary origin.