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[PMID]:28470783
[Au] Autor:Kryukova NV
[Ad] Endereço:Laboratory of morphological adaptations of vertebrates, Severtsov Institute of Ecology and Evolution, RAS, Moscow, 119071, Russia.
[Ti] Título:Functional analysis of the musculo-skeletal system of the gill apparatus in Heptranchias perlo (Chondrichthyes: Hexanchidae).
[So] Source:J Morphol;278(8):1075-1090, 2017 Aug.
[Is] ISSN:1097-4687
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Musculo-skeletal morphology is an indispensable source for understanding functional adaptations. Analysis of morphology of the branchial apparatus of Hexanchiform sharks can provide insight into aspects of their respiration that are difficult to observe directly. In this study, I compare the structure of the musculo-skeletal system of the gill apparatus of Heptranchias perlo and Squalus acanthias in respect to their adaptation for one of two respiratory mechanisms known in sharks, namely, the active two-pump (oropharyngeal and parabranchial) ventilation and the ram-jet ventilation. In both species, the oropharyngeal pump possesses two sets of muscles, one for compression and the other for expansion. The parabranchial pump only has constrictors. Expansion of this pump occurs only due to passive elastic recoil of the extrabranchial cartilages. In Squalus acanthias the parabranchial chambers are large and equipped by powerful superficial constrictors. These muscles and the outer walls of the parabranchial chambers are much reduced in Heptranchias perlo, and thus it likely cannot use this pump. However, this reduction allows for vertical elongation of outer gill slits which, along with greater number of gill pouches, likely decreases branchial resistance and, at the same time, increases the gill surface area, and can be regarded as an adaptation for ram ventilation at lower speeds.
[Mh] Termos MeSH primário: Brânquias/anatomia & histologia
Sistema Musculoesquelético/anatomia & histologia
Tubarões/anatomia & histologia
Tubarões/fisiologia
[Mh] Termos MeSH secundário: Animais
Osso e Ossos/anatomia & histologia
Cabeça/anatomia & histologia
Músculos/anatomia & histologia
Squalus acanthias/anatomia & histologia
Squalus acanthias/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1002/jmor.20695


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[PMID]:28832628
[Au] Autor:Chana-Munoz A; Jendroszek A; Sønnichsen M; Kristiansen R; Jensen JK; Andreasen PA; Bendixen C; Panitz F
[Ad] Endereço:Department of Molecular Biology and Genetics, Aarhus University, Tjele, Denmark.
[Ti] Título:Multi-tissue RNA-seq and transcriptome characterisation of the spiny dogfish shark (Squalus acanthias) provides a molecular tool for biological research and reveals new genes involved in osmoregulation.
[So] Source:PLoS One;12(8):e0182756, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The spiny dogfish shark (Squalus acanthias) is one of the most commonly used cartilaginous fishes in biological research, especially in the fields of nitrogen metabolism, ion transporters and osmoregulation. Nonetheless, transcriptomic data for this organism is scarce. In the present study, a multi-tissue RNA-seq experiment and de novo transcriptome assembly was performed in four different spiny dogfish tissues (brain, liver, kidney and ovary), providing an annotated sequence resource. The characterization of the transcriptome greatly increases the scarce sequence information for shark species. Reads were assembled with the Trinity de novo assembler both within each tissue and across all tissues combined resulting in 362,690 transcripts in the combined assembly which represent 289,515 Trinity genes. BUSCO analysis determined a level of 87% completeness for the combined transcriptome. In total, 123,110 proteins were predicted of which 78,679 and 83,164 had significant hits against the SwissProt and Uniref90 protein databases, respectively. Additionally, 61,215 proteins aligned to known protein domains, 7,208 carried a signal peptide and 15,971 possessed at least one transmembrane region. Based on the annotation, 81,582 transcripts were assigned to gene ontology terms and 42,078 belong to known clusters of orthologous groups (eggNOG). To demonstrate the value of our molecular resource, we show that the improved transcriptome data enhances the current possibilities of osmoregulation research in spiny dogfish by utilizing the novel gene and protein annotations to investigate a set of genes involved in urea synthesis and urea, ammonia and water transport, all of them crucial in osmoregulation. We describe the presence of different gene copies and isoforms of key enzymes involved in this process, including arginases and transporters of urea and ammonia, for which sequence information is currently absent in the databases for this model species. The transcriptome assemblies and the derived annotations generated in this study will support the ongoing research for this particular animal model and provides a new molecular tool to assist biological research in cartilaginous fishes.
[Mh] Termos MeSH primário: Osmorregulação
Análise de Sequência de RNA
Squalus acanthias/genética
Transcriptoma
[Mh] Termos MeSH secundário: Animais
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170824
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182756


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[PMID]:27146106
[Au] Autor:Thomas DB; Hiscox JD; Dixon BJ; Potgieter J
[Ad] Endereço:Institute of Natural and Mathematical Sciences, Massey University, Auckland, New Zealand.
[Ti] Título:3D scanning and printing skeletal tissues for anatomy education.
[So] Source:J Anat;229(3):473-81, 2016 09.
[Is] ISSN:1469-7580
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Detailed anatomical models can be produced with consumer-level 3D scanning and printing systems. 3D replication techniques are significant advances for anatomical education as they allow practitioners to more easily introduce diverse or numerous specimens into classrooms. Here we present a methodology for producing anatomical models in-house, with the chondrocranium cartilage from a spiny dogfish (Squalus acanthias) and the skeleton of a cane toad (Rhinella marina) as case studies. 3D digital replicas were produced using two consumer-level scanners and specimens were 3D-printed with selective laser sintering. The fidelity of the two case study models was determined with respect to key anatomical features. Larger-scale features of the dogfish chondrocranium and frog skeleton were all well-resolved and distinct in the 3D digital models, and many finer-scale features were also well-resolved, but some more subtle features were absent from the digital models (e.g. endolymphatic foramina in chondrocranium). All characters identified in the digital chondrocranium could be identified in the subsequent 3D print; however, three characters in the 3D-printed frog skeleton could not be clearly delimited (palatines, parasphenoid and pubis). Characters that were absent in the digital models or 3D prints had low-relief in the original scanned specimen and represent a minor loss of fidelity. Our method description and case studies show that minimal equipment and training is needed to produce durable skeletal specimens. These technologies support the tailored production of models for specific classes or research aims.
[Mh] Termos MeSH primário: Anatomia/educação
Osso e Ossos/anatomia & histologia
Modelos Anatômicos
Impressão Tridimensional
[Mh] Termos MeSH secundário: Animais
Bufo marinus/anatomia & histologia
Squalus acanthias/anatomia & histologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170821
[Lr] Data última revisão:
170821
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160506
[St] Status:MEDLINE
[do] DOI:10.1111/joa.12484


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[PMID]:27020803
[Au] Autor:Colonello JH; Cortés F; Belleggia M; Massa AM
[Ad] Endereço:Programa Pesquerías de Condrictios, Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), Paseo Victoria Ocampo N°1 Escollera Norte (7600), Mar del Plata, Argentina.
[Ti] Título:Reproductive and population parameters of spiny dogfish Squalus acanthias in the south-western Atlantic Ocean.
[So] Source:J Fish Biol;88(5):1758-75, 2016 May.
[Is] ISSN:1095-8649
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The objective of this study was to estimate reproductive and population parameters of the spiny dogfish Squalus acanthias for the south-western Atlantic Ocean. In total, 2714 specimens (1616 males and 1098 females) were collected from surveys carried out using research vessels. Males ranged from 225 to 861 mm total length (LT ) and females from 235 to 925 mm LT . The size at maturity of females (651 mm) was significantly greater than that of males (565 mm). The maximum proportion of mature individuals (Pmax ) of the gestation ogive was <1, which indicates that a proportion of mature females was not in gestation. This inactivity may be explained by the occurrence of resting periods between cycles or by the asynchrony of the reproductive cycle. The estimated Pmax for the maternity ogive suggested that about one third of mature females were in the maternity stage (i.e. with embryos >156 mm). The temporal and spatial co-occurrence of non-gravid adult females at different stages of ovarian development, as well as gravid females at all embryonic development stages would indicate that the female reproductive cycle in the south-western Atlantic Ocean is asynchronous. The results indicate that S. acanthias is susceptible to fishing pressure on account of its length at maturity, extended reproductive cycles and low fecundity.
[Mh] Termos MeSH primário: Reprodução
Squalus acanthias/fisiologia
[Mh] Termos MeSH secundário: Animais
Oceano Atlântico
Feminino
Fertilidade
Masculino
Densidade Demográfica
Caracteres Sexuais
Maturidade Sexual
Squalus acanthias/anatomia & histologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160330
[St] Status:MEDLINE
[do] DOI:10.1111/jfb.12940


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[PMID]:26707980
[Au] Autor:St Gelais AT; Costa-Pierce BA
[Ad] Endereço:Department of Marine Sciences, Marine Science Center, University of New England, Biddeford, ME 04005, USA. Electronic address: astgelais@une.edu.
[Ti] Título:Mercury concentrations in Northwest Atlantic winter-caught, male spiny dogfish (Squalus acanthias): A geographic mercury comparison and risk-reward framework for human consumption.
[So] Source:Mar Pollut Bull;102(1):199-205, 2016 Jan 15.
[Is] ISSN:1879-3363
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Mercury (Hg) contamination testing was conducted on winter-caught male spiny dogfish (Squalus acanthias) in southern New England and results compared to available data on Hg concentrations for this species. A limited risk-reward assessment for EPA (eicosapentanoic acid) and DHA (docosahexanoic acid) lipid concentrations of spiny dogfish was completed in comparison with other commonly consumed marine fish. Mean Hg concentrations were 0.19 ppm (±0.30) wet weight. In comparison, mean Hg concentrations in S. acanthias varied geographically ranging from 0.05 ppm (Celtic Sea) to 2.07 ppm (Crete, Mediterranean Sea). A risk-reward assessment for Hg and DHA+EPA placed S. acanthias in both "low-risk, high-reward" and "high-risk, high-reward" categories for consumption dependent on locations of the catch. Our results are limited and are not intended as consumption advisories but serve to illustrate the need for making more nuanced, geo-specific, consumption guidance for spiny dogfish that is inclusive of seafood traceability and nutritional benefits.
[Mh] Termos MeSH primário: Mercúrio/análise
Alimentos Marinhos
Squalus acanthias/metabolismo
[Mh] Termos MeSH secundário: Animais
Monitoramento Ambiental
Contaminação de Alimentos/análise
Geografia
Grécia
Seres Humanos
Masculino
Mar Mediterrâneo
Mercúrio/metabolismo
New England
Risco
Estações do Ano
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
FXS1BY2PGL (Mercury)
[Em] Mês de entrada:1610
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151229
[St] Status:MEDLINE


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[PMID]:26604860
[Au] Autor:Schwarz JS; de Jonge HR; Forrest JN
[Ad] Endereço:Yale College, Yale University, New Haven, Connecticut ; Department of Medicine, Yale School of Medicine, New Haven, Connecticut ; Mount Desert Island Biological Laboratory, Salisbury Cove, Maine.
[Ti] Título:Value of Organoids from Comparative Epithelia Models.
[So] Source:Yale J Biol Med;88(4):367-74, 2015 Dec.
[Is] ISSN:1551-4056
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Organoids have tremendous therapeutic potential. They were recently defined as a collection of organ-specific cell types, which self-organize through cell-sorting, develop from stem cells, and perform an organ specific function. The ability to study organoid development and growth in culture and manipulate their genetic makeup makes them particularly suitable for studying development, disease, and drug efficacy. Organoids show great promise in personalized medicine. From a single patient biopsy, investigators can make hundreds of organoids with the genetic landscape of the patient of origin. This genetic similarity makes organoids an ideal system in which to test drug efficacy. While many investigators assume human organoids are the ultimate model system, we believe that the generation of epithelial organoids of comparative model organisms has great potential. Many key transport discoveries were made using marine organisms. In this paper, we describe how deriving organoids from the spiny dogfish shark, zebrafish, and killifish can contribute to the fields of comparative biology and disease modeling with future prospects for personalized medicine.
[Mh] Termos MeSH primário: Epitélio/fisiologia
Organoides/fisiologia
[Mh] Termos MeSH secundário: Animais
Epitélio/efeitos dos fármacos
Fundulidae
Seres Humanos
Modelos Biológicos
Organoides/efeitos dos fármacos
Medicina de Precisão
Squalus acanthias
Peixe-Zebra
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.; REVIEW
[Em] Mês de entrada:1609
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151126
[St] Status:MEDLINE


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[PMID]:26050212
[Au] Autor:MacLellan RJ; Tunnah L; Barnett D; Wright PA; MacCormack T; Currie S
[Ad] Endereço:Department of Biochemistry, Mount Allison University, Sackville, NB, Canada.
[Ti] Título:Chaperone roles for TMAO and HSP70 during hyposmotic stress in the spiny dogfish shark (Squalus acanthias).
[So] Source:J Comp Physiol B;185(7):729-40, 2015 Oct.
[Is] ISSN:1432-136X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Salinity decreases are experienced by many marine elasmobranchs. To understand how these fishes cope with hyposmotic stress on a cellular level, we used the spiny dogfish shark (Squalus acanthias) as a model to test whether a reciprocal relationship exists between the cell's two primary protein protection mechanisms, the chemical (e.g., trimethylamine oxide, TMAO) and molecular (e.g., heat shock protein 70, HSP70) chaperone systems. This relationship is interesting given that many elasmobranchs are expected to gain water and lose osmolytes, chemical chaperones, and ions as they osmoconform to new, lowered salinity. Dogfish were cannulated for repeated blood sampling and exposed to 70% seawater (SW) for 48 h. These hyposmotic conditions had no effect on red blood cell (RBC) and white muscle TMAO concentrations, and did not result in HSP70 induction or signs of protein damage (i.e., increased ubiquitin), suggesting that TMAO levels were sufficiently protective in these tissues. However, in the gill, we observed a significant decrease in TMAO concentration and a significant induction of HSP70 as well as signs of protein damage. In the face of this cellular stress response, gill Na(+)/K(+)-ATPase (NKA) activity significantly increased during hyposmotic conditions, as expected. We suggest that this functional preservation in the gill is partly the result of HSP70 induction with lowered salinity. We conclude a reciprocal relationship between TMAO and HSP70 in the gills of dogfish as a result of in vivo hyposmotic stress. When osmotically induced protein damage surpasses the protective capacity of remaining TMAO, HSP70 is induced to preserve tissue and organismal function.
[Mh] Termos MeSH primário: Proteínas de Peixes/metabolismo
Brânquias/metabolismo
Proteínas de Choque Térmico HSP70/metabolismo
Metilaminas/metabolismo
Pressão Osmótica
Squalus acanthias/metabolismo
[Mh] Termos MeSH secundário: Adaptação Fisiológica
Animais
Masculino
Metilaminas/sangue
Músculos/metabolismo
Salinidade
Água do Mar
ATPase Trocadora de Sódio-Potássio/metabolismo
Squalus acanthias/sangue
Fatores de Tempo
Ureia/sangue
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Fish Proteins); 0 (HSP70 Heat-Shock Proteins); 0 (Methylamines); 8W8T17847W (Urea); EC 3.6.3.9 (Sodium-Potassium-Exchanging ATPase); FLD0K1SJ1A (trimethyloxamine)
[Em] Mês de entrada:1606
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150608
[St] Status:MEDLINE
[do] DOI:10.1007/s00360-015-0916-6


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[PMID]:25794843
[Au] Autor:Nawata CM; Walsh PJ; Wood CM
[Ad] Endereço:Bamfield Marine Sciences Centre, 100 Pachena Road, Bamfield, BC, V0R 1B0, Canada, cmnawata@email.arizona.edu.
[Ti] Título:Nitrogen metabolism, acid-base regulation, and molecular responses to ammonia and acid infusions in the spiny dogfish shark (Squalus acanthias).
[So] Source:J Comp Physiol B;185(5):511-25, 2015 Jul.
[Is] ISSN:1432-136X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Although they are ureotelic, marine elasmobranchs express Rh glycoproteins, putative ammonia channels. To address questions raised by a recent study on high environmental ammonia (HEA) exposure, dogfish were intravascularly infused for 24 h at 3 ml kg(-1) h(-1) with isosmotic NaCl (500 mmol l(-1), control), NH4HCO3 (500 mmol l(-1)), NH4Cl (500 mmol l(-1)), or HCl (as 125 mmol l(-1) HCl + 375 mmol l(-1) NaCl). While NaCl had no effect on arterial acid-base status, NH4HCO3 caused mild alkalosis, NH4Cl caused strong acidosis, and HCl caused lesser acidosis, all predominantly metabolic in nature. Total plasma ammonia (T(Amm)) and excretion rates of ammonia (J(Amm)) and urea-N (J(Urea-N)) were unaffected by NaCl or HCl. However, despite equal loading rates, plasma T(Amm) increased to a greater extent with NH4Cl, while J(Amm) increased to a greater extent with NH4HCO3 due to much greater increases in blood-to-water PNH3 gradients. As with HEA, both treatments caused large (90%) elevations of J(Urea-N), indicating that urea-N synthesis by the ornithine-urea cycle (OUC) is driven primarily by ammonia rather than HCO3(-). Branchial mRNA expressions of Rhbg and Rhp2 were unaffected by NH4HCO3 or NH4Cl, but v-type H(+)-ATPase was down-regulated by both treatments, and Rhbg and Na(+)/H(+) exchanger NHE2 were up-regulated by HCl. In the kidney, Rhbg was unresponsive to all treatments, but Rhp2 was up-regulated by HCl, and the urea transporter UT was up-regulated by HCl and NH4Cl. These responses are discussed in the context of current ideas about branchial, renal, and OUC function in this nitrogen-limited predator.
[Mh] Termos MeSH primário: Equilíbrio Ácido-Base/efeitos dos fármacos
Cloreto de Amônio/efeitos adversos
Bicarbonatos/efeitos adversos
Regulação da Expressão Gênica/efeitos dos fármacos
Nitrogênio/metabolismo
Squalus acanthias/fisiologia
[Mh] Termos MeSH secundário: Equilíbrio Ácido-Base/fisiologia
Amônia/sangue
Cloreto de Amônio/administração & dosagem
Análise de Variância
Animais
Bicarbonatos/administração & dosagem
Primers do DNA/genética
Ácido Clorídrico
Glicoproteínas de Membrana/metabolismo
Reação em Cadeia da Polimerase
Cloreto de Sódio
Espectrofotometria Atômica
Squalus acanthias/metabolismo
Ureia/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bicarbonates); 0 (DNA Primers); 0 (Membrane Glycoproteins); 01Q9PC255D (Ammonium Chloride); 451W47IQ8X (Sodium Chloride); 45JP4345C9 (ammonium bicarbonate); 7664-41-7 (Ammonia); 8W8T17847W (Urea); N762921K75 (Nitrogen); QTT17582CB (Hydrochloric Acid)
[Em] Mês de entrada:1603
[Cu] Atualização por classe:171014
[Lr] Data última revisão:
171014
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150322
[St] Status:MEDLINE
[do] DOI:10.1007/s00360-015-0898-4


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[PMID]:25687971
[Au] Autor:Esmann M; Fedosova NU; Olesen C
[Ad] Endereço:Department of Biomedicine, Ole Worms Alle 6, Aarhus University, DK-8000 Aarhus, Denmark. Electronic address: me@biomed.au.dk.
[Ti] Título:Na,K-ATPase structure/function relationships probed by the denaturant urea.
[So] Source:Biochim Biophys Acta;1848(5):1212-23, 2015 May.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Urea interacts with the Na,K-ATPase, leading to reversible as well as irreversible inhibition of the hydrolytic activity. The enzyme purified from shark rectal glands is more sensitive to urea than Na,K-ATPase purified from pig kidney. An immediate and reversible inhibition under steady-state conditions of hydrolytic activity at 37°C is demonstrated for the three reactions studied: the overall Na,K-ATPase activity, the Na-ATPase activity observed in the absence of K+ as well as the K+-dependent phosphatase reaction (K-pNPPase) seen in the absence of Na+. Half-maximal inhibition is seen with about 1M urea for shark enzyme and about 2M urea for pig enzyme. In the presence of substrates there is also an irreversible inhibition in addition to the reversible process, and we show that ATP protects against the irreversible inhibition for both the Na,K-ATPase and Na-ATPase reaction, whereas the substrate paranitrophenylphosphate leads to a slight increase in the rate of irreversible inhibition of the K-pNPPase. The rate of the irreversible inactivation in the absence of substrates is much more rapid for shark enzyme than for pig enzyme. The larger number of potentially urea-sensitive hydrogen bonds in shark enzyme compared to pig enzyme suggests that interference with the extensive hydrogen bonding network might account for the higher urea sensitivity of shark enzyme. The reversible inactivation is interpreted in terms of domain interactions and domain accessibilities using as templates the available crystal structures of Na,K-ATPase. It is suggested that a few interdomain hydrogen bonds are those mainly affected by urea during reversible inactivation.
[Mh] Termos MeSH primário: Trifosfato de Adenosina/metabolismo
Inibidores Enzimáticos/química
ATPase Trocadora de Sódio-Potássio/metabolismo
Ureia/química
[Mh] Termos MeSH secundário: Animais
Inibidores Enzimáticos/farmacologia
Ligações de Hidrogênio
Hidrólise
Cinética
Modelos Biológicos
Modelos Moleculares
Nitrofenóis/metabolismo
Compostos Organofosforados/metabolismo
Conformação Proteica
Desnaturação Proteica
Estrutura Terciária de Proteína
ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores
ATPase Trocadora de Sódio-Potássio/química
Squalus acanthias
Relação Estrutura-Atividade
Especificidade por Substrato
Suínos
Temperatura Ambiente
Ureia/farmacologia
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Enzyme Inhibitors); 0 (Nitrophenols); 0 (Organophosphorus Compounds); 330-13-2 (nitrophenylphosphate); 8L70Q75FXE (Adenosine Triphosphate); 8W8T17847W (Urea); EC 3.6.3.9 (Sodium-Potassium-Exchanging ATPase)
[Em] Mês de entrada:1509
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150218
[St] Status:MEDLINE


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[PMID]:25609784
[Au] Autor:Nawata CM; Walsh PJ; Wood CM
[Ad] Endereço:Bamfield Marine Sciences Centre, 100 Pachena Road, Bamfield, BC, Canada V0R 1B0 Department of Biology, McMaster University, 1280 Main Street, West, Hamilton, ON, Canada L8S 4K1 Department of Physiology, University of Arizona, 1501 N. Campbell Avenue Tucson, AZ 85724, USA cmnawata@email.arizona.edu.
[Ti] Título:Physiological and molecular responses of the spiny dogfish shark (Squalus acanthias) to high environmental ammonia: scavenging for nitrogen.
[So] Source:J Exp Biol;218(Pt 2):238-48, 2015 Jan 15.
[Is] ISSN:1477-9145
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In teleosts, a branchial metabolon links ammonia excretion to Na(+) uptake via Rh glycoproteins and other transporters. Ureotelic elasmobranchs are thought to have low branchial ammonia permeability, and little is known about Rh function in this ancient group. We cloned Rh cDNAs (Rhag, Rhbg and Rhp2) and evaluated gill ammonia handling in Squalus acanthias. Control ammonia excretion was <5% of urea-N excretion. Sharks exposed to high environmental ammonia (HEA; 1 mmol(-1) NH4HCO3) for 48 h exhibited active ammonia uptake against partial pressure and electrochemical gradients for 36 h before net excretion was re-established. Plasma total ammonia rose to seawater levels by 2 h, but dropped significantly below them by 24-48 h. Control ΔP(NH3) (the partial pressure gradient of NH3) across the gills became even more negative (outwardly directed) during HEA. Transepithelial potential increased by 30 mV, negating a parallel rise in the Nernst potential, such that the outwardly directed NH4(+) electrochemical gradient remained unchanged. Urea-N excretion was enhanced by 90% from 12 to 48 h, more than compensating for ammonia-N uptake. Expression of Rhp2 (gills, kidney) and Rhbg (kidney) did not change, but branchial Rhbg and erythrocytic Rhag declined during HEA. mRNA expression of branchial Na(+)/K(+)-ATPase (NKA) increased at 24 h and that of H(+)-ATPase decreased at 48 h, while expression of the potential metabolon components Na(+)/H(+) exchanger2 (NHE2) and carbonic anhydrase IV (CA-IV) remained unchanged. We propose that the gill of this nitrogen-limited predator is poised not only to minimize nitrogen loss by low efflux permeability to urea and ammonia but also to scavenge ammonia-N from the environment during HEA to enhance urea-N synthesis.
[Mh] Termos MeSH primário: Amônia/metabolismo
Brânquias/fisiologia
Squalus acanthias/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Amônia/sangue
Animais
Sequência de Bases
DNA Complementar
Dieta/estatística & dados numéricos
Glicoproteínas/metabolismo
Rim
Dados de Sequência Molecular
Nitrogênio/metabolismo
ATPases Translocadoras de Prótons
Água do Mar/química
ATPase Trocadora de Sódio-Potássio
Ureia/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Complementary); 0 (Glycoproteins); 7664-41-7 (Ammonia); 8W8T17847W (Urea); EC 3.6.3.14 (Proton-Translocating ATPases); EC 3.6.3.9 (Sodium-Potassium-Exchanging ATPase); N762921K75 (Nitrogen)
[Em] Mês de entrada:1510
[Cu] Atualização por classe:150122
[Lr] Data última revisão:
150122
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150123
[St] Status:MEDLINE
[do] DOI:10.1242/jeb.114967



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