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Leone FA, Fabri LM, Costa MIC, Moraes CM, Garçon DP, McNamara JC. Differential effects of cobalt ions in vitro on gill (Na +, K +)-ATPase kinetics in the Blue crab Callinectes danae (Decapoda, Brachyura). Comp Biochem Physiol C Toxicol Pharmacol 2023; 274:109757. [PMID: 37741603 DOI: 10.1016/j.cbpc.2023.109757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 09/13/2023] [Accepted: 09/20/2023] [Indexed: 09/25/2023]
Abstract
We used the gill (Na+, K+)-ATPase as a molecular marker to provide a comprehensive kinetic analysis of the effects of Co2+in vitro on the modulation of K+-phosphatase activity in the Blue crab Callinectes danae. Co2+ can stimulate or inhibit K+-phosphatase activity. With Mg2+, K+-phosphatase activity is almost completely inhibited by Co2+. Co2+ stimulates K+-phosphatase activity similarly to Mg2+ although with a ≈4.5-fold greater affinity. At saturating Mg2+ concentrations, Mg2+ displaces bound Co2+ from the Mg2+-binding site in a concentration dependent manner, but Co2+ cannot displace Mg2+ from its binding site even at millimolar concentrations. Saturation by Co2+ of the Mg2+ binding site does not affect pNPP recognition by the enzyme. Substitution of Mg2+ by Co2+ slightly increases enzyme affinity for K+ and NH4+. Independently of Mg2+, inhibition by ouabain or sodium ions is unaffected by Co2+. Investigation of gill (Na+, K+)-ATPase K+-phosphatase activity provides a reliable tool to examine the kinetic effects of Co2+ with and without Na+ and ATP. Given that the toxic effects of Co2+ at the molecular level are poorly understood, these findings advance our knowledge of the mechanism of action of Co2+ on the crustacean gill (Na+, K+)-ATPase.
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Affiliation(s)
- Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
| | - Leonardo M Fabri
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Brazil
| | - Maria I C Costa
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Cintya M Moraes
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Brazil
| | | | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, Brazil. https://twitter.com/@maracoani
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Fabri LM, Garçon DP, Moraes CM, Pinto MR, McNamara JC, Leone FA. A kinetic characterization of the gill V(H +)-ATPase from two hololimnetic populations of the Amazon River shrimp Macrobrachium amazonicum. Comp Biochem Physiol B Biochem Mol Biol 2023; 268:110880. [PMID: 37517460 DOI: 10.1016/j.cbpb.2023.110880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/27/2023] [Accepted: 07/27/2023] [Indexed: 08/01/2023]
Abstract
This investigation examines the kinetic characteristics and effect of acclimation to a brackish medium (21 ‰S) on gill V(H+)-ATPase activity in two hololimnetic populations of M. amazonicum. We also investigate the cellular immunolocalization of the enzyme. Immunofluorescence findings demonstrate that the V(H+)-ATPase c-subunit is distributed in the apical pillar cells of shrimps in fresh water but is absent after acclimation to 21 ‰S for 10 days. V(H+)-ATPase activity from the Tietê River population is ≈50% greater than the Grande River population, comparable to a wild population from the Santa Elisa Reservoir, but is 2-fold less than in cultivated shrimps. V(H+)-ATPase activity in the Tietê and the Grande River shrimps is abolished after 21 ‰S acclimation. The apparent affinities of the V(H+)-ATPase for ATP (0.27 ± 0.04 and 0.16 ± 0.03 mmol L-1, respectively) and Mg2+ (0.28 ± 0.05 and 0.14 ± 0.02 mmol L-1, respectively) are similar in both populations. The absence of V(H+)-ATPase activity in salinity-acclimated shrimps and its apical distribution in shrimps in fresh water underpins the importance of the crustacean V(H+)-ATPase for ion uptake in fresh water.
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Affiliation(s)
- Leonardo M Fabri
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Brazil
| | - Daniela P Garçon
- Universidade Federal do Triângulo Mineiro, Campus Universitário de Iturama, 38280-000, Brazil
| | - Cintya M Moraes
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Brazil
| | - Marcelo R Pinto
- Laboratory of Biopathology and Molecular Biology, University of Uberaba, Uberaba, Minas Gerais, Brazil
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil.; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, 11000-600, Brazil. https://twitter.com/maracoani
| | - Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil.
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Thurman CL, Shih HT, McNamara JC. Minuca panema (Coelho, 1972): Resurrection of a Fiddler Crab Species from Brazil Closely Related to Minuca burgersi (Holthuis, 1967) (Crustacea, Decapoda, Brachyura, Ocypodidae). Zool Stud 2023; 62:e45. [PMID: 37965297 PMCID: PMC10641435 DOI: 10.6620/zs.2023.62-45] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 07/09/2023] [Indexed: 11/16/2023]
Abstract
We redescribe a species of fiddler crab, Minuca panema (Coelho, 1972), from the Atlantic coast of South America. It is closely related to M. mordax (Smith, 1870), and until now, the taxon has been considered to be synonymous with another closely related species Minuca burgersi (Holthuis, 1967). However, we found that two clades of M. burgersi sensu lato were restricted to the Caribbean Basin. This distribution differs from than that of M. panema, which occurs primarily along the eastern coast of South America, ranging from the island of Trinidad to Praia da Armação, Santa Catarina, Brazil. Based on our field studies, the geographical boundary between M. burgersi sensu stricto and M. panema is the Tobago Basin, north of Trinidad. Since the two species diverged only 3 to 4 million years ago, as dated from the phylogeny of the genus Minuca Bott 1954, there are few reliable morphological features that can be used to distinguish them clearly. In live crabs, there is a striking difference in coloration between the cherryred South American M. panema and the rusty-red Caribbean M. burgersi sensu lato. In males, the pattern of tubercles on the inner surface of the major cheliped varies between the two species. In females, the vulva is slightly larger in M. burgersi sensu stricto. Ocean tides and currents together with siltation owing to freshwater outflow from the Amazon and Orinoco rivers most likely have driven the divergence of these species. In the Caribbean, small tidal amplitudes have minimized long-distance gene flow in M. burgersi sensu stricto from isolated insular lagoons. In contrast, large tidal amplitudes and exposed habitats on riverbanks along the eastern Atlantic coast of South America have enabled long-distance dispersal in M. panema. DNA analysis reveals that haplotypes of cytochrome c oxidase subunit 1 are not shared between the species. Since natural selection and/or genetic drift have yet to produce extensive morphological divergences between M. panema and M. burgersi sensu stricto, we speculate that changes in the genes regulating mitochondrial DNA functions have led to speciation at the molecular level. According to the mitonuclear compatibility concept, we propose that mitochondrial DNA may be at the forefront of speciation events and that co-evolved mitonuclear interactions are responsible for some of the earliest genetic incompatibilities arising among isolated populations.
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Affiliation(s)
- Carl L Thurman
- Department of Biology, University of Northern Iowa, 1227 West 27th St., Cedar Falls, IA 50614-0421, USA. E-mail: (Thurman). Tel: +1 319 273-2276
| | - Hsi-Te Shih
- Department of Biology, University of Northern Iowa, 1227 West 27th St., Cedar Falls, IA 50614-0421, USA. E-mail: (Thurman). Tel: +1 319 273-2276
| | - John C McNamara
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirao Preto 14040-901, Brazil. E-mail: (McNamara). Tel: +55 16 3315 3687
- Centro de Biologia Marinha, Universidade de São Paulo, 11600-000 SP, Brazil
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Fabri LM, Moraes CM, Costa MIC, Garçon DP, Fontes CFL, Pinto MR, McNamara JC, Leone FA. Salinity-dependent modulation by protein kinases and the FXYD2 peptide of gill (Na +, K +)-ATPase activity in the freshwater shrimp Macrobrachium amazonicum (Decapoda, Palaemonidae). Biochim Biophys Acta Biomembr 2022; 1864:183982. [PMID: 35671812 DOI: 10.1016/j.bbamem.2022.183982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 05/16/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
The geographical distribution of aquatic crustaceans is determined by ambient factors like salinity that modulate their biochemistry, physiology, behavior, reproduction, development and growth. We investigated the effects of exogenous pig FXYD2 peptide and endogenous protein kinases A and C on gill (Na+, K+)-ATPase activity, and characterized enzyme kinetic properties in a freshwater population of Macrobrachium amazonicum in fresh water (<0.5 ‰ salinity) or acclimated to 21 ‰S. Stimulation by FXYD2 peptide and inhibition by endogenous kinase phosphorylation are salinity-dependent. While without effect in shrimps in fresh water, the FXYD2 peptide stimulated activity in salinity-acclimated shrimps by ≈50 %. PKA-mediated phosphorylation inhibited gill (Na+, K+)-ATPase activity by 85 % in acclimated shrimps while PKC phosphorylation markedly inhibited enzyme activity in freshwater- and salinity-acclimated shrimps. The (Na+, K+)-ATPase in salinity-acclimated shrimp gills hydrolyzed ATP at a Vmax of 54.9 ± 1.8 nmol min-1 mg-1 protein, corresponding to ≈60 % that of freshwater shrimps. Mg2+ affinity increased with salinity acclimation while K+ affinity decreased. (Ca2+, Mg2+)-ATPase activity increased while V(H+)- and Na+- or K+-stimulated activities decreased on salinity acclimation. The 120-kDa immunoreactive band expressed in salinity-acclimated shrimps suggests nonspecific α-subunit phosphorylation by PKA and/or PKC. These alterations in (Na+, K+)-ATPase kinetics in salinity-acclimated M. amazonicum may result from regulatory mechanisms mediated by phosphorylation via protein kinases A and C and the FXYD2 peptide rather than through the expression of a different α-subunit isoform. This is the first demonstration of gill (Na+, K+)-ATPase regulation by protein kinases in freshwater shrimps during salinity challenge.
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Affiliation(s)
- Leonardo M Fabri
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Brazil
| | - Cintya M Moraes
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Brazil
| | - Maria I C Costa
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Carlos F L Fontes
- Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Brazil
| | - Marcelo R Pinto
- Laboratório de Biopatologia e Biologia Molecular, Universidade de Uberaba, Uberaba, Brazil
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, Brazil
| | - Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
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Capparelli MV, McNamara JC, Thurman CL, Pérez-Ceballos R, Gómez-Ponce MA, Cardoso-Mohedano JG, Moulatlet GM. Can tolerances of multiple stressors and calculated safety margins in fiddler crabs predict responses to extreme environmental conditions resulting from climate change? Mar Pollut Bull 2022; 179:113674. [PMID: 35489093 DOI: 10.1016/j.marpolbul.2022.113674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 03/18/2022] [Accepted: 04/16/2022] [Indexed: 06/14/2023]
Abstract
To comprehend mangrove crab responses to predicted global climate changes, we assessed submersion and desiccation survival durations and salinity tolerances and upper thermal limits in fiddler crabs from Isla del Carmen, Yucatán Peninsula. Based on their tolerances of extreme ambient conditions, we also calculated safety margins using abiotic monitoring data. The two most terrestrial species, Minuca rapax and Leptuca panacea, exhibited submersion tolerances of from 22 to 40 h, and desiccation tolerances of from 30 to 55 h; LC50's were ≈45‰S and UT50's were ≈40 °C. The two least terrestrial species, M. vocator and L. speciosa, were less tolerant of all experimental challenges, showing submersion and desiccation tolerances of <6 h, and LC50's of 36‰S and UT50's of 38 °C. While these fiddler crabs inhabit niches closer to their salinity and desiccation/submersion tolerances than to their temperature limits, all are clearly vulnerable to the multiple stressors that accompany anticipated global climate change.
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Affiliation(s)
- Mariana V Capparelli
- Estación el Carmen, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Carretera Carmen-Puerto Real km. 9.5, C. P 24157 Ciudad del Carmen, Campeche, Mexico.
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofa, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP 14040-901, Brazil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, SP 11600-000, Brazil
| | - Carl L Thurman
- Department of Biology, University of Northern Iowa, Cedar Falls, IA 50614-0421, USA
| | - Rosela Pérez-Ceballos
- Estación el Carmen, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Carretera Carmen-Puerto Real km. 9.5, C. P 24157 Ciudad del Carmen, Campeche, Mexico
| | - Mario A Gómez-Ponce
- Estación el Carmen, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Carretera Carmen-Puerto Real km. 9.5, C. P 24157 Ciudad del Carmen, Campeche, Mexico
| | - José-Gilberto Cardoso-Mohedano
- Estación el Carmen, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Carretera Carmen-Puerto Real km. 9.5, C. P 24157 Ciudad del Carmen, Campeche, Mexico
| | - Gabriel M Moulatlet
- Red de Biología Evolutiva, Instituto de Ecología, A.C., Xalapa, Veracruz, Mexico
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Garçon DP, Fabri LM, Moraes CM, Costa MIC, Freitas RS, McNamara JC, Leone FA. Effects of ammonia on gill (Na +, K +)-ATPase kinetics in a hololimnetic population of the Amazon River shrimp Macrobrachium amazonicum. Aquat Toxicol 2022; 246:106144. [PMID: 35339850 DOI: 10.1016/j.aquatox.2022.106144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 03/04/2022] [Accepted: 03/12/2022] [Indexed: 06/14/2023]
Abstract
Water quality is essential for successful aquaculture. For freshwater shrimp farming, ammonia concentrations can increase considerably, even when culture water is renewed frequently, consequently increasing the risk of ammonia intoxication. We investigated ammonia lethality (LC50-96 h) in a hololimnetic population of the Amazon River shrimp Macrobrachium amazonicum from the Paraná/Paraguay River basin, including the effects of exposure to 4.93 mg L-1 total ammonia concentration on gill (Na+, K+)-ATPase activity. The mean LC50-96 h was 49.27 mg L-1 total ammonia, corresponding to 1.8 mg L-1 un-ionized ammonia. Except for NH4+ affinity that increased 2.5-fold, that of the gill (Na+, K+)-ATPase for ATP, Mg2+, Na+, K+ and ouabain was unchanged after ammonia exposure. Western blotting of gill microsomal preparations from fresh caught shrimps showed a single immunoreactive band of ≈110 kDa, corresponding to the gill (Na+, K+)-ATPase α-subunit. Ammonia exposure increased (Na+, K+)-ATPase activity by ≈25%, coincident with an additional 130 kDa α-subunit immunoreactive band, and increased K+-stimulated and V(H+)-ATPase activities by ≈2.5-fold. Macrobrachium amazonicum from the Paraná/Paraguay River basin is as tolerant to ammonia as are other Amazon River basins populations, showing toxicity comparable to that of marine crustaceans.
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Affiliation(s)
- Daniela P Garçon
- Campus Universitário de Iturama, Universidade Federal do Triângulo Mineiro, Iturama, MG, Brasil
| | - Leonardo M Fabri
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Cintya M Moraes
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Maria Izabel C Costa
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
| | - Renata S Freitas
- Campus Universitário de Iturama, Universidade Federal do Triângulo Mineiro, Iturama, MG, Brasil
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, SP, Brasil
| | - Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil.
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Capparelli MV, McNamara JC, Araujo GS, Cruz ACF, Abessa DMS. Use of an Integrated Geochemical and Ecotoxicological Approach to Evaluate Sediment Metal Contamination in Three Protected Estuarine Areas Along the Coast of São Paulo State, Brazil. Bull Environ Contam Toxicol 2021; 106:355-362. [PMID: 33392684 DOI: 10.1007/s00128-020-03076-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
We compared sediment quality in estuaries at three locations along the coast of São Paulo State, Brazil, using geochemical analyses and whole sediment toxicity tests, during the southern summer and winter of 2013. Each locality is afforded a distinct degree of legal protection, and exhibits a different level of metal pollution: overall, Rio Diana (RD, the most polluted, a Permanent Protection Area) > Rio Itapanhaú (RI, intermediate contamination, an Environmental Protection Area) > Rio Picinguaba (RP, pristine, a State Park). Chronic sediment toxicity tests evaluated reproductive rates of the copepod Nitokra sp. RI sediments showed the highest metal concentrations and toxicity in both seasons. Metal concentrations at RD were low but toxic in summer. RP sediments were not contaminated, suggesting effective legal protection from pollution at this locality. RI and RD, although provided some legal protection, showed clear signs of environmental degradation, emphasizing the need for more effective pollution control.
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Affiliation(s)
- M V Capparelli
- Facultad de Ciencias de la Tierra y Agua, Universidad Regional Amazónica Ikiam, km 7 vía Muyuna, Tena, Napo, Ecuador.
| | - J C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, 14040-901, Brazil
- Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, SP, 11600-000, Brazil
| | - G S Araujo
- Universidade Estadual Paulista, Campus de São Vicente, São Vicente, SP, 11380-972, Brazil
| | - A C F Cruz
- Universidade Estadual Paulista, Campus de São Vicente, São Vicente, SP, 11380-972, Brazil
| | - D M S Abessa
- Universidade Estadual Paulista, Campus de São Vicente, São Vicente, SP, 11380-972, Brazil
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Capparelli MV, McNamara JC, Grosell MG. Tissue Accumulation and the Effects of Long-Term Dietary Copper Contamination on Osmoregulation in the Mudflat Fiddler Crab Minuca rapax (Crustacea, Ocypodidae). Bull Environ Contam Toxicol 2020; 104:755-762. [PMID: 32394051 DOI: 10.1007/s00128-020-02872-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 05/02/2020] [Indexed: 06/11/2023]
Abstract
We examined copper accumulation in the hemolymph, gills and hepatopancreas, and hemolymph osmolality, Na+ and Cl- concentrations, together with gill Na+/K+-ATPase and carbonic anhydrase activities, after dietary copper delivery (0, 100 or 500 Cu µg g-1) for 12 days in a fiddler crab, Minuca rapax. In contaminated crabs, copper concentration decreased in the hemolymph and hepatopancreas, but increased in the gills. Hemolymph osmolality and gill Na+/K+-ATPase activity increased while hemolymph [Na+] and [Cl-] and gill carbonic anhydrase activity decreased. Excretion likely accounts for the decreased hemolymph and hepatopancreas copper titers. Dietary copper clearly affected osmoregulatory ability and hemolymph Na+ and Cl- regulation in M. rapax. Gill copper accumulation decreased carbonic anhydrase activity, suggesting that dietary copper affects acid-base balance. Elevated gill Na+/K+-ATPase activity appears to compensate for the ion-regulatory disturbance. These effects of dietary copper illustrate likely impacts on semi-terrestrial species that feed on metal-contaminated sediments.
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Affiliation(s)
- M V Capparelli
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, 14040-901, Brasil.
- Facultad de Ciencias de La Tierra Y Agua, Universidad Regional Amazónica Ikiam, km 7, vía a Muyuna, Tena, Napo, Ecuador.
| | - J C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, 14040-901, Brasil
- Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, SP, 11600-000, Brasil
| | - M G Grosell
- Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA
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Moraes CM, Lucena MN, Garçon DP, Pinto MR, Fabri LM, Faleiros RO, Fontes CFL, McNamara JC, Leone FA. Biochemical Characterization and Allosteric Modulation by Magnesium of (Na +, K +)-ATPase Activity in the Gills of the Red Mangrove Crab Goniopsis cruentata (Brachyura, Grapsidae). J Membr Biol 2020; 253:229-245. [PMID: 32440867 DOI: 10.1007/s00232-020-00120-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 05/02/2020] [Indexed: 11/26/2022]
Abstract
We provide a kinetic characterization of (Na+, K+)-ATPase activity in a posterior gill microsomal fraction from the grapsid crab Goniopsis cruentata. (Na+, K+)-ATPase activity constitutes 95% of total ATPase activity, and sucrose density centrifugation reveals an ATPase activity peak between 25 and 35% sucrose, distributed into two, partially separated protein fractions. The (Na+, K+)-ATPase α-subunit is localized throughout the ionocyte cytoplasm and has an Mr of ≈ 10 kDa and hydrolyzes ATP obeying cooperative kinetics. Low (VM = 186.0 ± 9.3 nmol Pi min-1 mg-1 protein and K0.5 = 0.085 ± 0.004 mmol L-1) and high (VM = 153.4 ± 7.7 nmol Pi min-1 mg-1 protein and K0.5 = 0.013 ± 0.0006 mmol L-1) affinity ATP binding sites were characterized. At low ATP concentrations, excess Mg2+ stimulates the enzyme, triggering exposure of a high-affinity binding site that accounts for 50% of (Na+, K+)-ATPase activity. Stimulation by Mg2+ (VM = 425.9 ± 25.5 nmol Pi min-1 mg-1 protein, K0.5 = 0.16 ± 0.01 mmol L-1), K+ (VM = 485.3 ± 24.3 nmol Pi min-1 mg-1 protein, K0.5 = 0.9 ± 0.05 mmol L-1), Na+ (VM = 425.0 ± 23.4 nmol Pi min-1 mg-1 protein, K0.5 = 5.1 ± 0.3 mmol L-1) and NH4+ (VM = 497.9 ± 24.9 nmol Pi min-1 mg-1 protein, K0.5 = 9.7 ± 0.5 mmol L-1) obeys cooperative kinetics. Ouabain inhibits up to 95% of ATPase activity with KI = 196.6 ± 9.8 µmol L-1. This first kinetic characterization of the gill (Na+, K+)-ATPase in Goniopsis cruentata enables better comprehension of the biochemical underpinnings of osmoregulatory ability in this semi-terrestrial mangrove crab.
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Affiliation(s)
- Cintya M Moraes
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14040-901, Brazil
| | - Malson N Lucena
- Instituto de Biociências, Universidade Federal do Mato Grosso do Sul, Campo Grande, MS, Brazil
| | | | - Marcelo R Pinto
- Laboratório de Biopatologia e Biologia Molecular Universidade Uberaba, Uberaba, MG, Brazil
| | - Leonardo M Fabri
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14040-901, Brazil
| | - Rogério O Faleiros
- Departamento de Ciências Agrárias e Biológicas, Universidade Federal do Espírito Santo, São Mateus, ES, Brazil
| | - Carlos F L Fontes
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
- Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, SP, Brazil
| | - Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14040-901, Brazil.
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Lucena MN, Garçon DP, Fontes CFL, Fabri LM, Moraes CM, McNamara JC, Leone FA. Dopamine binding directly up-regulates (Na +, K +)-ATPase activity in the gills of the freshwater shrimp Macrobrachium amazonicum. Comp Biochem Physiol A Mol Integr Physiol 2019; 233:39-47. [PMID: 30936021 DOI: 10.1016/j.cbpa.2019.03.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 03/20/2019] [Accepted: 03/25/2019] [Indexed: 01/11/2023]
Abstract
We examined the effects of exogenous dopamine on gill (Na+, K+)-ATPase activity in vitro in microsomal preparations from juvenile or adult freshwater shrimp, Macrobrachium amazonicum. Dopamine had no effect on enzyme activity in juveniles but stimulated activity in adult shrimp gills by ≈35%. Stimulation of the gill (Na+, K+)-ATPase in adult shrimps by 100 mmol L-1 dopamine was characterized kinetically by varying ATP, MgATP, and Na+ and K+ concentrations, together with inhibition by ouabain. Dopamine stimulated ATP hydrolysis by ≈40% obeying Michaelis-Menten kinetics, reaching VM = 190.5 ± 15.7 nmol Pi min-1 mg-1 protein, KM remaining unaltered. Stimulation by Na+ (≈50%) and K+ (≈25%) revealed distinct kinetic profiles: although KM values were similar, Na+ stimulation followed cooperative kinetics, contrasting with the Michaelian kinetics seen for K+. Stimulation by MgATP increased activity by ≈30% with little change in KM. Similar saturation profiles were seen for ouabain inhibition with very similar calculated KI values. Our findings suggest that dopamine may be involved in hemolymph sodium homeostasis by directly binding to the gill (Na+, K+)-ATPase at a site different from ouabain, thus stimulating enzyme activity in an ontogenetic stage-specific manner. However, dopamine binding does not affect enzyme affinity for cations and ouabain. This is the first report of the direct action of dopamine in stimulating the crustacean gill (Na+, K+)-ATPase.
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Affiliation(s)
- Malson N Lucena
- Departamento de Química - Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, SP, Brazil
| | - Daniela P Garçon
- Campus Universitário de Iturama, Universidade Federal do Triângulo Mineiro, 38280-000, MG, Brazil
| | - Carlos F L Fontes
- Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, 21941-590, RJ, Brazil
| | - Leonardo M Fabri
- Departamento de Química - Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, SP, Brazil
| | - Cintya M Moraes
- Departamento de Química - Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, SP, Brazil
| | - John C McNamara
- Departamento de Biologia - Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, SP, Brazil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, SP, Brazil
| | - Francisco A Leone
- Departamento de Química - Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, SP, Brazil.
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Fabri LM, Lucena MN, Garçon DP, Moraes CM, McNamara JC, Leone FA. Kinetic characterization of the gill (Na+, K+)-ATPase in a hololimnetic population of the diadromous Amazon River shrimp Macrobrachium amazonicum (Decapoda, Palaemonidae). Comp Biochem Physiol B Biochem Mol Biol 2019; 227:64-74. [DOI: 10.1016/j.cbpb.2018.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 09/18/2018] [Indexed: 10/28/2022]
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12
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Faleiros RO, Garçon DP, Lucena MN, McNamara JC, Leone FA. Short- and long-term salinity challenge, osmoregulatory ability, and (Na +, K +)-ATPase kinetics and α-subunit mRNA expression in the gills of the thinstripe hermit crab Clibanarius symmetricus (Anomura, Diogenidae). Comp Biochem Physiol A Mol Integr Physiol 2018; 225:16-25. [PMID: 29932975 DOI: 10.1016/j.cbpa.2018.06.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 06/06/2018] [Accepted: 06/12/2018] [Indexed: 12/27/2022]
Abstract
The evolutionary history of the Crustacea reveals ample adaptive radiation and the subsequent occupation of many osmotic niches resulting from physiological plasticity in their osmoregulatory mechanisms. We evaluate osmoregulatory ability in the intertidal, thinstripe hermit crab Clibanarius symmetricus after short-term exposure (6 h) or long-term acclimation (10 days) to a wide salinity range, also analyzing kinetic behavior and α-subunit mRNA expression of the gill (Na+, K+)-ATPase. The crab strongly hyper-regulates its hemolymph at 5 and 15‰S (Salinity, g L-1) but weakly hyper-regulates up to ≈27‰S. After 6 h exposure to 35‰S and 45‰S, C. symmetricus slightly hypo-regulates its hemolymph, becoming isosmotic after 10 days acclimation to these salinities. (Na+, K+)-ATPase specific activity decreases with increasing salinity for both exposure periods, reflecting physiological adjustment to isosmoticity. At low salinities, the gill enzyme exhibits a single, low affinity ATP binding site. However, at elevated salinities, a second, high affinity, ATP binding site appears, independently of exposure time. (Na+, K+)-ATPase α-subunit mRNA expression increases only after 10 days acclimation to 5‰S. Our findings suggest that hemolymph hyper-regulation is effected by alterations in enzyme activity during short-term exposure, but is sustained by increased mRNA expression during long-term acclimation. The decrease in gill (Na+, K+)-ATPase activity seen as a consequence of increasing salinity appears to underlie biochemical adjustments to hemolymph isosmoticity as hypo-regulatory ability diminishes.
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Affiliation(s)
- Rogério O Faleiros
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil; Unidade Acadêmica Especial de Ciências Biológicas, Universidade Federal de Jataí, Jataí 75801-615, GO, Brazil
| | - Daniela P Garçon
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil; Universidade Federal do Triângulo Mineiro, Iturama 38280-000, MG, Brazil
| | - Malson N Lucena
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil; Instituto de Biociências, Universidade Federal do Mato Grosso do Sul, Campo Grande 79070-900, MS, Brazil
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião 11000-600, SP, Brazil
| | - Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil.
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Capparelli MV, McNamara JC, Grosell M. Effects of waterborne copper delivered under two different exposure and salinity regimes on osmotic and ionic regulation in the mudflat fiddler crab, Minuca rapax (Ocypodidae, Brachyura). Ecotoxicol Environ Saf 2017; 143:201-209. [PMID: 28550807 DOI: 10.1016/j.ecoenv.2017.05.042] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 04/20/2017] [Accepted: 05/20/2017] [Indexed: 06/07/2023]
Abstract
The effects of exposure to copper (Cu) on tissue Cu accumulation, on hemolymph osmotic, Na+ and Cl- regulation, and on gill Na+/K+-ATPase (NKA) and carbonic anhydrase (CA) activities were evaluated in the fiddler crab Minuca rapax. Waterborne copper was delivered to the crabs at one of three salinities (seawater at 25‰ salinity [S] = isosmotic control; distilled water [<0.1‰ S] = hypo-osmotic medium; or 60‰ S = hyper-osmotic seawater) either for 5 days in a 0.5-cm water film containing 0, 50, 150, 250 or 500µg Cu/L with free access to a dry surface, or in crabs fully submerged for 5h at 0, 250 or 500µg Cu/L. In the crabs with free access to a dry surface, the highest Cu concentrations were found in the hemolymph and hepatopancreas with some accumulation in the gills; accumulation in the hemolymph and gills was enhanced in low salinity but was salinity independent in the hepatopancreas. Osmotic regulation was unaffected by Cu exposure; however Na+ and Cl- hypo- regulation was impaired by Cu in 25 and 60‰ S. Gill NKA activity was stimulated 2-fold at 50µg Cu/L and markedly inhibited at 150µg Cu/L and above in 0 and 25‰ S. Gill CA was inhibited in <0.1‰ S but stimulated in 25 and 60‰ S; an inverse concentration-CA activity response was seen above 150µg Cu/L for all salinities. In the submerged crabs, Cu accumulated in all tissues in 60‰ S; however, there was no clear-cut Cu concentration-accumulation relationship evident in any tissue for either exposure regime, likely owing to the crabs' ability to regulate Cu. Copper exposure diminished osmotic, [Na+] and [Cl-] hypo-regulatory ability, especially in higher salinities. Gill NKA activity was markedly inhibited by Cu overall, and particularly above 250µg Cu/L in <0.1‰ S. Gill CA activity was inhibited in 25‰ S but inconsistently affected in 0 and 60‰ S. These findings show that Minuca rapax is affected both physiologically and biochemically by Cu contamination, although to different degrees, depending on the delivery regime, salinity, copper concentration and target tissue.
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Affiliation(s)
- Mariana V Capparelli
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901 SP, Brasil.
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901 SP, Brasil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião 11600-000 SP, Brasil
| | - Martin Grosell
- Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Marine Biology and Fisheries, Miami, Florida
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Farias DL, Lucena MN, Garçon DP, Mantelatto FL, McNamara JC, Leone FA. A Kinetic Characterization of the Gill (Na +, K +)-ATPase from the Semi-terrestrial Mangrove Crab Cardisoma guanhumi Latreille, 1825 (Decapoda, Brachyura). J Membr Biol 2017; 250:517-534. [PMID: 28840273 DOI: 10.1007/s00232-017-9978-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 08/09/2017] [Indexed: 11/25/2022]
Abstract
We provide a kinetic characterization of (Na+, K+)-ATPase activity in a posterior gill microsomal fraction from the semi-terrestrial mangrove crab Cardisoma guanhumi. Sucrose density gradient centrifugation reveals two distinct membrane fractions showing considerable (Na+, K+)-ATPase activity, but also containing other microsomal ATPases. The (Na+, K+)-ATPase, notably immuno-localized to the apical region of the epithelial pillar cells, and throughout the pillar cell bodies, has an M r of around 110 kDa and hydrolyzes ATP with V M = 146.8 ± 6.3 nmol Pi min-1 mg protein-1 and K M = 0.05 ± 0.003 mmol L-1 obeying Michaelis-Menten kinetics. While stimulation by Na+ (V M = 139.4 ± 6.9 nmol Pi min-1 mg protein-1, K M = 4.50 ± 0.22 mmol L-1) also follows Michaelis-Menten kinetics, modulation of (Na+, K+)-ATPase activity by MgATP (V M = 136.8 ± 6.5 nmol Pi min-1 mg protein-1, K 0.5 = 0.27 ± 0.04 mmol L-1), K+ (V M = 140.2 ± 7.0 nmol Pi min-1 mg protein-1, K 0.5 = 0.17 ± 0.008 mmol L-1), and NH4+ (V M = 149.1 ± 7.4 nmol Pi min-1 mg protein-1, K 0.5 = 0.60 ± 0.03 mmol L-1) shows cooperative kinetics. Ouabain (K I = 52.0 ± 2.6 µmol L-1) and orthovanadate (K I = 1.0 ± 0.05 µmol L-1) inhibit total ATPase activity by around 75%. At low Mg2+ concentrations, ATP is an allosteric modulator of the enzyme. This is the first study to provide a kinetic characterization of the gill (Na+, K+)-ATPase in C. guanhumi, and will be useful in better comprehending the biochemical underpinnings of osmoregulatory ability in a semi-terrestrial mangrove crab.
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Affiliation(s)
- Daniel L Farias
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Prêto, SP, 14040-901, Brazil
| | - Malson N Lucena
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Prêto, SP, 14040-901, Brazil
| | - Daniela P Garçon
- DPG, Campus Universitário de Iturama, Universidade Federal do Triângulo Mineiro, Iturama, Minas Gerais, 38280-000, Brazil
| | - Fernando L Mantelatto
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Prêto, SP, 14040-901, Brazil
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Prêto, SP, 14040-901, Brazil
- Centro de Biologia Marinha, São Sebastião, SP, 11000-600, Brazil
| | - Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Prêto, SP, 14040-901, Brazil.
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Faria SC, Faleiros RO, Brayner FA, Alves LC, Bianchini A, Romero C, Buranelli RC, Mantelatto FL, McNamara JC. Macroevolution of thermal tolerance in intertidal crabs from Neotropical provinces: A phylogenetic comparative evaluation of critical limits. Ecol Evol 2017; 7:3167-3176. [PMID: 28480016 PMCID: PMC5415543 DOI: 10.1002/ece3.2741] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 12/06/2016] [Accepted: 12/18/2016] [Indexed: 11/08/2022] Open
Abstract
Thermal tolerance underpins most biogeographical patterns in ectothermic animals. Macroevolutionary patterns of thermal limits have been historically evaluated, but a role for the phylogenetic component in physiological variation has been neglected. Three marine zoogeographical provinces are recognized throughout the Neotropical region based on mean seawater temperature (Tm): the Brazilian (Tm = 26 °C), Argentinian (Tm = 15 °C), and Magellanic (Tm = 9 °C) provinces. Microhabitat temperature (MHT) was measured, and the upper (UL 50) and lower (LL 50) critical thermal limits were established for 12 eubrachyuran crab species from intertidal zones within these three provinces. A molecular phylogenetic analysis was performed by maximum likelihood using the 16S mitochondrial gene, also considering other representative species to enable comparative evaluations. We tested for: (1) phylogenetic pattern of MHT, UL 50, and LL 50; (2) effect of zoogeographical province on the evolution of both limits; and (3) evolutionary correlation between MHT and thermal limits. MHT and UL 50 showed strong phylogenetic signal at the species level while LL 50 was unrelated to phylogeny, suggesting a more plastic evolution. Province seems to have affected the evolution of thermal tolerance, and only UL 50 was dependent on MHT. UL 50 was similar between the two northern provinces compared to the southernmost while LL 50 differed markedly among provinces. Apparently, critical limits are subject to different environmental pressures and thus manifest unique evolutionary histories. An asymmetrical macroevolutionary scenario for eubrachyuran thermal tolerance seems likely, as the critical thermal limits are differentially inherited and environmentally driven.
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Affiliation(s)
- Samuel C. Faria
- Departamento de BiologiaFaculdade de FilosofiaCiências e Letras de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
- Present address: Instituto de Ciências BiológicasUniversidade Federal do Rio GrandeRio GrandeBrazil
| | - Rogério O. Faleiros
- Departamento de BiologiaFaculdade de FilosofiaCiências e Letras de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
| | - Fábio A. Brayner
- Centro de Pesquisas Aggeu MagalhãesFiocruzRecifeBrazil
- Laboratório de Imunopatologia Keizo AsamiLIKA/UFPERecifeBrazil
| | - Luiz C. Alves
- Centro de Pesquisas Aggeu MagalhãesFiocruzRecifeBrazil
- Laboratório de Imunopatologia Keizo AsamiLIKA/UFPERecifeBrazil
| | - Adalto Bianchini
- Instituto de Ciências BiológicasUniversidade Federal do Rio GrandeRio GrandeBrazil
| | - Carolina Romero
- Centro Austral de Investigaciones CientíficasCADIC‐CONICETUshuaiaArgentina
| | - Raquel C. Buranelli
- Departamento de BiologiaFaculdade de FilosofiaCiências e Letras de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
| | - Fernando L. Mantelatto
- Departamento de BiologiaFaculdade de FilosofiaCiências e Letras de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
| | - John C. McNamara
- Departamento de BiologiaFaculdade de FilosofiaCiências e Letras de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
- Centro de Biologia MarinhaUniversidade de São PauloSão SebastiãoBrazil
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Capparelli MV, Abessa DM, McNamara JC. Effects of metal contamination in situ on osmoregulation and oxygen consumption in the mudflat fiddler crab Uca rapax (Ocypodidae, Brachyura). Comp Biochem Physiol C Toxicol Pharmacol 2016; 185-186:102-111. [PMID: 26992327 DOI: 10.1016/j.cbpc.2016.03.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 03/04/2016] [Accepted: 03/09/2016] [Indexed: 01/13/2023]
Abstract
The contamination of estuaries by metals can impose additional stresses on estuarine species, which may exhibit a limited capability to adjust their regulatory processes and maintain physiological homeostasis. The mudflat fiddler crab Uca rapax is a typical estuarine crab, abundant in both pristine and contaminated areas along the Atlantic coast of Brazil. This study evaluates osmotic and ionic regulatory ability and gill Na(+)/K(+)-ATPase activity in different salinities (<0.5, 25 and 60‰ S) and oxygen consumption rates at different temperatures (15, 25 and 35°C) in U. rapax collected from localities along the coast of São Paulo State showing different histories of metal contamination (most contaminated Ilha Diana, Santos>Rio Itapanhaú, Bertioga>Picinguaba, Ubatuba [pristine reference site]). Our findings show that the contamination of U. rapax by metals in situ leads to bioaccumulation and induces biochemical and physiological changes compared to crabs from the pristine locality. U. rapax from the contaminated sites exhibit stronger hyper- and hypo-osmotic regulatory abilities and show greater gill Na(+)/K(+)-ATPase activities than crabs from the pristine site, revealing that the underlying biochemical machinery can maintain systemic physiological processes functioning well. However, oxygen consumption, particularly at elevated temperatures, decreases in crabs showing high bioaccumulation titers but increases in crabs with low/moderate bioaccumulation levels. These data show that U. rapax chronically contaminated in situ exhibits compensatory biochemical and physiological adjustments, and reveal the importance of studies on organisms exposed to metals in situ, particularly estuarine invertebrates subject to frequent changes in natural environmental parameters like salinity and temperature.
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Affiliation(s)
- Mariana V Capparelli
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil.
| | - Denis M Abessa
- Universidade Estadual Paulista, Campus de São Vicente, São Vicente 11380-972, SP, Brazil
| | - John C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil; Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião 11600-000, SP, Brazil
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17
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Pinto MR, Lucena MN, Faleiros RO, Almeida EA, McNamara JC, Leone FA. Effects of ammonia stress in the Amazon river shrimp Macrobrachium amazonicum (Decapoda, Palaemonidae). Aquat Toxicol 2016; 170:13-23. [PMID: 26571214 DOI: 10.1016/j.aquatox.2015.10.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 06/05/2023]
Abstract
We evaluate the effects of total ammonia nitrogen-N (TAN) exposure for 72h on (Na(+),K(+))- and V(H(+))-ATPase activities and on their subunit expressions in gills of the diadromous freshwater shrimp Macrobrachium amazonicum. Specific (Na(+),K(+))- and V(H(+))-ATPase activities increased roughly 1.5- to 2-fold, respectively, after exposure to 2.0mmolL(-1) TAN. Quantitative RT-PCR analyses revealed a 2.5-fold increase in V(H(+))-ATPase B subunit mRNA expression while (Na(+),K(+))-ATPase α-subunit expression was unchanged. Immunohistochemical analyses of the gill lamellae located the (Na(+),K(+))-ATPase throughout the intralamellar septal cells, independently of TAN concentration, while the V(H(+))-ATPase was located in both the apical pillar cell flanges and pillar cell bodies. Systemic stress parameters like total hemocyte count decreased by 30% after exposure to 2.0mmolL(-1) TAN, accompanied by increased activities of the oxidative stress enzymes superoxide dismutase, glutathione reductase and glucose-6-phosphate dehydrogenase in the gills. The stress responses of M. amazonicum to elevated TAN include increases in gill (Na(+),K(+))- and V(H(+))-ATPase activities that are accompanied by changes in oxidative stress enzyme activities, immune system effects and an increase in gill V(H(+))-ATPase gene expression. These findings likely underpin physiological effects in a crustacean like M. amazonicum that exploits multiple ecosystems during its life cycle, as well as under culture conditions that may significantly impact shrimp production by the aquaculture industry.
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Affiliation(s)
- Marcelo R Pinto
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto/USP, Brazil
| | - Malson N Lucena
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto/USP, Brazil
| | | | - Eduardo Alves Almeida
- Universidade Estadual Paulista Júlio de Mesquita Filho - Campus de São José do Rio Preto, Brazil
| | - John C McNamara
- Departamento de Biologia -Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto/USP, Brazil
| | - Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto/USP, Brazil.
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18
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Leone FA, Garçon DP, Lucena MN, Faleiros RO, Azevedo SV, Pinto MR, McNamara JC. Gill-specific (Na+, K+)-ATPase activity and α-subunit mRNA expression during low-salinity acclimation of the ornate blue crab Callinectes ornatus (Decapoda, Brachyura). Comp Biochem Physiol B Biochem Mol Biol 2015; 186:59-67. [DOI: 10.1016/j.cbpb.2015.04.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 04/16/2015] [Accepted: 04/21/2015] [Indexed: 12/27/2022]
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Lucena MN, Pinto MR, Garçon DP, McNamara JC, Leone FA. A kinetic characterization of the gill V(H+)-ATPase in juvenile and adult Macrobrachium amazonicum, a diadromous palaemonid shrimp. Comp Biochem Physiol B Biochem Mol Biol 2015; 181:15-25. [DOI: 10.1016/j.cbpb.2014.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 09/05/2014] [Accepted: 11/07/2014] [Indexed: 10/24/2022]
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França JL, Pinto MR, Lucena MN, Garçon DP, Valenti WC, McNamara JC, Leone FA. Subcellular Localization and Kinetic Characterization of a Gill (Na+, K+)-ATPase from the Giant Freshwater Prawn Macrobrachium rosenbergii. J Membr Biol 2013; 246:529-43. [DOI: 10.1007/s00232-013-9565-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 05/31/2013] [Indexed: 10/26/2022]
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Garçon DP, Lucena MN, Pinto MR, Fontes CFL, McNamara JC, Leone FA. Synergistic stimulation by potassium and ammonium of K(+)-phosphatase activity in gill microsomes from the crab Callinectes ornatus acclimated to low salinity: novel property of a primordial pump. Arch Biochem Biophys 2012; 530:55-63. [PMID: 23262318 DOI: 10.1016/j.abb.2012.12.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 11/28/2012] [Accepted: 12/04/2012] [Indexed: 11/16/2022]
Abstract
We provide an extensive characterization of the modulation by p-nitrophenylphosphate, Mg²⁺, Na⁺, K(+), Rb⁺, NH(4)(+) and pH of gill microsomal K⁺-phosphatase activity in the posterior gills of Callinectes ornatus acclimated to low salinity (21‰). The synergistic stimulation by K⁺ and NH(4)(+) of the K⁺-phosphatase activity is a novel finding, and may constitute a species-specific feature of K(+)/NH(4)(+) interplay that regulates crustacean gill (Na⁺, K⁺)-ATPase activity. p-Nitrophenylphosphate was hydrolyzed at a maximum rate (V) of 69.2 ± 2.8nmolPimin⁻¹mg⁻¹ with K(0.5)=2.3 ± 0.1mmolL(-1), obeying cooperative kinetics (n(H)=1.7). Stimulation by Mg²⁺ (V=70.1 ± 3.0nmolPimin⁻¹mg⁻¹, K(0.5)=0.88 ± 0.04mmolL⁻¹), K⁺ (V=69.6 ± 2.7nmolPimin⁻¹mg⁻¹, K(0.5)=1.60 ± 0.07mmolL⁻¹) and NH(4)(+) (V=90.8 ± 4.0nmolPimin⁻¹mg⁻¹, K(0.5)=9.2 ± 0.3mmol L⁻¹) all displayed site-site interaction kinetics. In the presence of NH(4)(+), enzyme affinity for K⁺ unexpectedly increased by 7-fold, while affinity for NH(4)(+) was 28-fold greater in the presence than absence of K⁺. Ouabain partially inhibited K⁺-phosphatase activity (K(I)=320 ± 14.0μmolL⁻¹), more effectively when NH(4)(+) was present (K(I)=240 ± 12.0μmolL⁻¹). We propose a model for the synergistic stimulation by K⁺ and NH(4)(+) of the K⁺-phosphatase activity of the (Na⁺, K⁺)-ATPase from C. ornatus posterior gill tissue.
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Affiliation(s)
- Daniela P Garçon
- Departamento de Biologia Molecular, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, Brazil
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Lucena MN, Garçon DP, Mantelatto FL, Pinto MR, McNamara JC, Leone FA. Hemolymph ion regulation and kinetic characteristics of the gill (Na+, K+)-ATPase in the hermit crab Clibanarius vittatus (Decapoda, Anomura) acclimated to high salinity. Comp Biochem Physiol B Biochem Mol Biol 2012; 161:380-91. [DOI: 10.1016/j.cbpb.2012.01.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 12/05/2011] [Accepted: 01/05/2012] [Indexed: 10/14/2022]
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23
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Garçon DP, Lucena MN, França JL, McNamara JC, Fontes CFL, Leone FA. Na⁺,K⁺-ATPase activity in the posterior gills of the blue crab, Callinectes ornatus (Decapoda, Brachyura): modulation of ATP hydrolysis by the biogenic amines spermidine and spermine. J Membr Biol 2011; 244:9-20. [PMID: 21972069 DOI: 10.1007/s00232-011-9391-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 08/11/2011] [Indexed: 11/24/2022]
Abstract
We investigated the effect of the exogenous polyamines spermine, spermidine and putrescine on modulation by ATP, K⁺, Na⁺, NH₄⁺ and Mg²⁺ and on inhibition by ouabain of posterior gill microsomal Na⁺,K⁺-ATPase activity in the blue crab, Callinectes ornatus, acclimated to a dilute medium (21‰ salinity). This is the first kinetic demonstration of competition between spermine and spermidine for the cation sites of a crustacean Na⁺,K⁺-ATPase. Polyamine inhibition is enhanced at low cation concentrations: spermidine almost completely inhibited total ATPase activity, while spermine inhibition attained 58%; putrescine had a negligible effect on Na⁺,K⁺-ATPase activity. Spermine and spermidine affected both V and K for ATP hydrolysis but did not affect ouabain-insensitive ATPase activity. ATP hydrolysis in the absence of spermine and spermidine obeyed Michaelis-Menten behavior, in contrast to the cooperative kinetics seen for both polyamines. Modulation of V and K by K⁺, Na⁺, NH₄⁺ and Mg²⁺ varied considerably in the presence of spermine and spermidine. These findings suggest that polyamine inhibition of Na⁺,K⁺-ATPase activity may be of physiological relevance to crustaceans that occupy habitats of variable salinity.
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Affiliation(s)
- Daniela P Garçon
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras da Universidade de São Paulo, Ribeirão Preto, Avenida Bandeirantes 3900, Ribeirão Preto, SP 14040-901, Brazil
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24
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Leone FA, Furriel RPM, McNamara JC, Horisberger JD, Borin IA. Cation transport coupled to ATP hydrolysis by the (Na, K)-ATPase: An integrated, animated model. Biochem Mol Biol Educ 2010; 38:276-279. [PMID: 21567843 DOI: 10.1002/bmb.20404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
An Adobe® animation is presented for use in undergraduate Biochemistry courses, illustrating the mechanism of Na(+) and K(+) translocation coupled to ATP hydrolysis by the (Na, K)-ATPase, a P(2c) -type ATPase, or ATP-powered ion pump that actively translocates cations across plasma membranes. The enzyme is also known as an E(1) /E(2) -ATPase as it undergoes conformational changes between the E(1) and E(2) forms during the pumping cycle, altering the affinity and accessibility of the transmembrane ion-binding sites. The animation is based on Horisberger's scheme that incorporates the most recent significant findings to have improved our understanding of the (Na, K)-ATPase structure-function relationship. The movements of the various domains within the (Na, K)-ATPase α-subunit illustrate the conformational changes that occur during Na(+) and K(+) translocation across the membrane and emphasize involvement of the actuator, nucleotide, and phosphorylation domains, that is, the "core engine" of the pump, with respect to ATP binding, cation transport, and ADP and P(i) release.
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Affiliation(s)
- Francisco A Leone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901 Ribeirão Preto, São Paulo, Brasil.
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25
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Masui DC, Mantelatto FL, McNamara JC, Furriel RP, Leone FA. Na+, K+-ATPase activity in gill microsomes from the blue crab, Callinectes danae, acclimated to low salinity: Novel perspectives on ammonia excretion. Comp Biochem Physiol A Mol Integr Physiol 2009; 153:141-8. [DOI: 10.1016/j.cbpa.2009.01.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Revised: 01/28/2009] [Accepted: 01/28/2009] [Indexed: 11/17/2022]
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26
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Masui DC, Silva ECC, Mantelatto FLM, McNamara JC, Barrabin H, Scofano HM, Fontes CFL, Furriel RPM, Leone FA. The crustacean gill (Na+,K+)-ATPase: allosteric modulation of high- and low-affinity ATP-binding sites by sodium and potassium. Arch Biochem Biophys 2008; 479:139-44. [PMID: 18796291 DOI: 10.1016/j.abb.2008.08.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 08/26/2008] [Accepted: 08/27/2008] [Indexed: 10/21/2022]
Abstract
The blue crab, Callinectes danae, tolerates exposure to a wide salinity range employing mechanisms of compensatory ion uptake when in dilute media. Although the gill (Na+,K+)-ATPase is vital to hyperosmoregulatory ability, the interactions occurring at the sites of ATP binding on the molecule itself are unknown. Here, we investigate the modulation by Na+ and K+ of homotropic interactions between the ATP-binding sites, and of phosphoenzyme formation of the (Na+,K+)-ATPase from the posterior gills of this euryhaline crab. The contribution of the high- and low-affinity ATP-binding sites to maximum velocity was similar for both Na+ and K+. However, in contrast to Na+, a threshold K+ concentration triggers the appearance of the high-affinity binding sites, displacing the saturation curve to lower ATP concentrations.Further, a low-affinity site for phosphorylation is present on the enzyme. These findings reveal notable differences in the catalytic mechanism of the crustacean (Na+,K+)-ATPase compared to the vertebrate enzyme.
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Affiliation(s)
- D C Masui
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto 14040-901, SP, Brazil
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27
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Silva ECC, Masui DC, Furriel RPM, Mantelatto FLM, McNamara JC, Barrabin H, Leone FA, Scofano HM, Fontes CFL. Regulation by the exogenous polyamine spermidine of Na,K-ATPase activity from the gills of the euryhaline swimming crab Callinectes danae (Brachyura, Portunidae). Comp Biochem Physiol B Biochem Mol Biol 2008; 149:622-9. [PMID: 18272416 DOI: 10.1016/j.cbpb.2007.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Revised: 12/28/2007] [Accepted: 12/28/2007] [Indexed: 11/25/2022]
Abstract
Euryhaline crustaceans rarely hyporegulates and employ the driving force of the Na,K-ATPase, located at the basal surface of the gill epithelium, to maintain their hemolymph osmolality within a range compatible with cell function during hyper-regulation. Since polyamine levels increase during the adaptation of crustaceans to hyperosmotic media, we investigate the effect of exogenous polyamines on Na,K-ATPase activity in the posterior gills of Callinectes danae, a euryhaline swimming crab. Polyamine inhibition was dependent on cation concentration, charge and size in the following order: spermine>spermidine>putrescine. Spermidine affected K(0.5) values for Na(+) with minor alterations in K(0.5) values for K(+) and NH(4)(+), causing a decrease in maximal velocities under saturating Na(+), K(+) and NH(4)(+) concentrations. Phosphorylation measurements in the presence of 20 microM ATP revealed that the Na,K-ATPase possesses a high affinity site for this substrate. In the presence of 10 mM Na(+), both spermidine and spermine inhibited formation of the phosphoenzyme; however, in the presence of 100 mM Na(+), the addition of these polyamines allowed accumulation of the phosphoenzyme. The polyamines inhibited pumping activity, both by competing with Na(+) at the Na(+)-binding site, and by inhibiting enzyme dephosphorylation. These findings suggest that polyamine-induced inhibition of Na,K-ATPase activity may be physiologically relevant during migration to fully marine environments.
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Affiliation(s)
- E C C Silva
- Instituto de Bioquímica Médica, Laboratório de Estrutura e Regulação de Proteínas e ATPases, Programa de Biologia Estrutural, CCS, Bloco H, 2 andar, sala 26, 21941-590, RJ, Brazil
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28
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Santos LCF, Belli NM, Augusto A, Masui DC, Leone FA, McNamara JC, Furriel RPM. Gill (Na+,K+)-ATPase in diadromous, freshwater palaemonid shrimps: Species-specific kinetic characteristics and α-subunit expression. Comp Biochem Physiol A Mol Integr Physiol 2007; 148:178-88. [PMID: 17521934 DOI: 10.1016/j.cbpa.2007.04.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2007] [Revised: 04/02/2007] [Accepted: 04/03/2007] [Indexed: 10/23/2022]
Abstract
To better comprehend physiological adaptation to dilute media and the molecular mechanisms underlying ammonia excretion in palaemonid shrimps, we characterized the (Na+,K+)-ATPase from Macrobrachium amazonicum gills, disclosing high- (K(0.5) = 4.2+/-0.2 micromol L(-1); V = 33.9+/-1.9 U mg(-1)) and low-affinity (K(0.5) = 0.144+/-0.010 mmol L(-1); V = 232.9+/-15.3 U mg(-1)) ATP hydrolyzing sites. Stimulation by Na+ (K(0.5) = 5.5+/-0.3 mmol L(-1); V = 275.1+/-15.1 U mg(-1)), Mg2+ (K(0.5) = 0.79+/-0.06 mmol L(-1); V = 261.9+/-18.3 U mg(-1)), K+ (K(M) = 0.88+/-0.04 mmol L(-1); V = 271.8+/-10.9 U mg(-1)) and NH4(+) (K(M) = 5.0+/-0.2 mmol L(-1); V = 385.9+/-15.8 U mg(-1)) obeys single saturation curves, activity being stimulated synergistically by NH4(+) and K+. There is a single K+ binding site, NH4(+) binding to a second, exclusive site, stimulating activity by 33%, modulating K+ affinity. (Na+,K+)-ATPase activity constitutes approximately 80% of total ATPase activity (K(Iouabain) = 147.5+/-8.9 micromol L(-1)); Na+-, K+-, Ca2+-, V- and F(o)F(1)-ATPases are also present. M. amazonicum microsomal fractions possess approximately 2-fold less (Na+,K+)-ATPase alpha-subunit than M. olfersi, consistent with a 2.6-fold lower specific activity. These differences in (Na+, K+)-ATPase stimulation by ATP and ions, and specific activities of other ATPases, suggest the presence of distinct biochemical adaptations to life in fresh water in these related species.
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Affiliation(s)
- L C F Santos
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
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29
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Freire CA, Onken H, McNamara JC. A structure-function analysis of ion transport in crustacean gills and excretory organs. Comp Biochem Physiol A Mol Integr Physiol 2007; 151:272-304. [PMID: 17604200 DOI: 10.1016/j.cbpa.2007.05.008] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 05/08/2007] [Accepted: 05/11/2007] [Indexed: 11/29/2022]
Abstract
Osmotic and ionic regulation in the Crustacea is mostly accomplished by the multifunctional gills, together with the excretory organs. In addition to their role in gas exchange, the gills constitute organs of active, transepithelial, ion transport, an activity of major importance that underlies many essential physiological functions like osmoregulation, calcium homeostasis, ammonium excretion and extracellular pH regulation. This review focuses on structure-function relationships in crustacean gills and excretory effectors, from the organ to molecular levels of organization. We address the diversity of structural architectures encountered in different crustacean gill types, and in constituent cell types, before examining the physiological mechanisms of Na(+), Cl(-), Ca(2+) and NH(4)(+) transport, and of acid-base equivalents, based on findings obtained over the last two decades employing advanced techniques. The antennal and maxillary glands constitute the principal crustacean excretory organs, which have received less attention in functional studies. We examine the diversity present in antennal and maxillary gland architecture, highlighting the structural similarities between both organ types, and we analyze the functions ascribed to each glandular segment. Emphasis is given to volume and osmoregulatory functions, capacity to produce dilute urine in freshwater crustaceans, and the effect of acclimation salinity on urine volume and composition. The microanatomy and diversity of function ascribed to gills and excretory organs are appraised from an evolutionary perspective, and suggestions made as to future avenues of investigation that may elucidate evolutionary and adaptive trends underpinning the invasion and exploitation of novel habitats.
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Affiliation(s)
- Carolina A Freire
- Departamento de Fisiologia, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba, PR, 81531-990, Brazil.
| | - Horst Onken
- Department of Biological Sciences, Wagner College, Staten Island, NY 10301, USA
| | - John C McNamara
- Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, 14040-901, Brazil
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Garçon DP, Masui DC, Mantelatto FLM, McNamara JC, Furriel RPM, Leone FA. K+ and NH4(+) modulate gill (Na+, K+)-ATPase activity in the blue crab, Callinectes ornatus: fine tuning of ammonia excretion. Comp Biochem Physiol A Mol Integr Physiol 2006; 147:145-55. [PMID: 17276114 DOI: 10.1016/j.cbpa.2006.12.020] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2006] [Revised: 12/07/2006] [Accepted: 12/07/2006] [Indexed: 10/23/2022]
Abstract
To better comprehend the mechanisms of ionic regulation, we investigate the modulation by Na+, K+, NH4(+) and ATP of the (Na+, K+)-ATPase in a microsomal fraction from Callinectes ornatus gills. ATP hydrolysis obeyed Michaelis-Menten kinetics with KM=0.61+/-0.03 mmol L(-1) and maximal rate of V=116.3+/-5.4 U mg(-1). Stimulation by Na+ (V=110.6+/-6.1 U mg(-1); K0.5=6.3+/-0.2 mmol L(-1)), Mg2+ (V=111.0+/-4.7 U mg(-1); K0.5=0.53+/-0.03 mmol L(-1)), NH4(+) (V=173.3+/-6.9 U mg(-1); K0.5=5.4+/-0.2 mmol L(-1)) and K+ (V=116.0+/-4.9 U mg(-1); K0.5=1.5+/-0.1 mmol L(-1)) followed a single saturation curve, although revealing site-site interactions. In the absence of NH4(+), ouabain (K(I)=74.5+/-1.2 micromol L(-1)) and orthovanadate inhibited ATPase activity by up to 87%; the inhibition patterns suggest the presence of F0F1 and K+-ATPases but not Na+-, V- or Ca2+-ATPase as contaminants. (Na+, K+)-ATPase activity was synergistically modulated by K+ and NH4(+). At 10 mmol L(-1) K+, increasing NH4(+) concentrations stimulated maximum activity to V=185.9+/-7.4 U mg(-1). However, at saturating NH4(+) (50 mmol L(-1)), increasing K+ concentrations did not stimulate activity further. Our findings provide evidence that the C. ornatus gill (Na+, K+)-ATPase may be particularly well suited for extremely efficient active NH4(+) excretion. At elevated NH4(+) concentrations, the enzyme is fully active, regardless of hemolymph K+ concentration, and K+ cannot displace NH4(+) from its exclusive binding sites. Further, the binding of NH4(+) to its specific sites induces an increase in enzyme apparent affinity for K+, which may contribute to maintaining K+ transport, assuring that exposure to elevated ammonia concentrations does not lead to a decrease in intracellular potassium levels. This is the first report of modulation by ammonium ions of C. ornatus gill (Na+, K+)-ATPase, and should further our understanding of NH4(+) excretion in benthic crabs.
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Affiliation(s)
- D P Garçon
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
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31
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Gonçalves RR, Masui DC, McNamara JC, Mantelatto FLM, Garçon DP, Furriel RPM, Leone FA. A kinetic study of the gill (Na+, K+)-ATPase, and its role in ammonia excretion in the intertidal hermit crab, Clibanarius vittatus. Comp Biochem Physiol A Mol Integr Physiol 2006; 145:346-56. [PMID: 16931080 DOI: 10.1016/j.cbpa.2006.07.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2006] [Revised: 06/29/2006] [Accepted: 07/10/2006] [Indexed: 10/24/2022]
Abstract
To better comprehend the role of gill ion regulatory mechanisms, the modulation by Na(+), K(+), NH(4)(+) and ATP of (Na(+), K(+))-ATPase activity was examined in a posterior gill microsomal fraction from the hermit crab, Clibanarius vittatus. Under saturating Mg(2+), Na(+) and K(+) concentrations, two well-defined ATP hydrolyzing sites were revealed. ATP was hydrolyzed at the high-affinity sites at a maximum rate of V=19.1+/-0.8 U mg(-1) and K(0.5)=63.8+/-2.9 nmol L(-1), obeying cooperative kinetics (n(H)=1.9); at the low-affinity sites, hydrolysis obeyed Michaelis-Menten kinetics with K(M)=44.1+/-2.6 mumol L(-1) and V=123.5+/-6.1 U mg(-1). Stimulation by Na(+) (V=149.0+/-7.4 U mg(-1); K(M)=7.4+/-0.4 mmol L(-1)), Mg(2+) (V=132.0+/-5.3 U mg(-1); K(0.5)=0.36+/-0.02 mmol L(-1)), NH(4)(+) (V=245.6+/-9.8 U mg(-1); K(M)=4.5+/-0.2 mmol L(-1)) and K(+) (V=140.0+/-4.9 U mg(-1); K(M)=1.5+/-0.1 mmol L(-1)) followed a single saturation curve and, except for Mg(2+), obeyed Michaelis-Menten kinetics. Under optimal ionic conditions, but in the absence of NH(4)(+), ouabain (K(I)=117.3+/-3.5 mumol L(-1)) and orthovanadate inhibited up to 67% of the ATPase activity. The inhibition studies performed suggest the presence of F(0)F(1), V- and P-ATPases, but not Na(+)-, K(+)- or Ca(2+)-ATPases as contaminants in the gill microsomal preparation. (Na(+), K(+))-ATPase activity was synergistically modulated by NH(4)(+) and K(+). At 20 mmol L(-1) K(+), a maximum rate of V=290.8+/-14.5 U mg(-1) was seen as NH(4)(+) concentration was increased up to 50 mmol L(-1). However, at fixed NH(4)(+) concentrations, no additional stimulation was found for increasing K(+) concentrations (V=135.2+/-4.1 U mg(-1) and V=236.6+/-9.5 U mg(-1) and for 10 and 30 mmol L(-1) NH(4)(+), respectively). This is the first report to detail ionic modulation of gill (Na(+), K(+))-ATPase in C. vittatus, revealing an asymmetrical, synergistic stimulation of the enzyme by K(+) and NH(4)(+), as yet undescribed for other (Na(+), K(+))-ATPases, and should provide a better understanding of NH(4)(+) excretion in pagurid crabs.
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Affiliation(s)
- Rúbia R Gonçalves
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Ribeirão Preto 14040-901, SP, Brazil
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Mendonça NN, Masui DC, McNamara JC, Leone FA, Furriel RPM. Long-term exposure of the freshwater shrimp Macrobrachium olfersii to elevated salinity: effects on gill (Na+,K+)-ATPase alpha-subunit expression and K+-phosphatase activity. Comp Biochem Physiol A Mol Integr Physiol 2006; 146:534-43. [PMID: 16529963 DOI: 10.1016/j.cbpa.2006.01.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2005] [Revised: 01/06/2006] [Accepted: 01/12/2006] [Indexed: 10/24/2022]
Abstract
The kinetic properties of a microsomal gill (Na+,K+)-ATPase from the freshwater shrimp, Macrobrachium olfersii, acclimated to 21 per thousand salinity for 10 days were investigated using the substrate p-nitrophenylphosphate. The enzyme hydrolyzed this substrate obeying cooperative kinetics at a rate of 123.6+/-4.9 U mg-1 and K0.5=1.31+/-0.05 mmol L-1. Stimulation of K+-phosphatase activity by magnesium (Vmax=125.3+/-7.5 U mg-1; K0.5=2.09+/-0.06 mmol L-1), potassium (Vmax=134.2+/-6.7 U mg-1; K0.5=1.33+/-0.06 mmol L-1) and ammonium ions (Vmax=130.1+/-5.9 U mg-1; K0.5=11.4+/-0.5 mmol L-1) was also cooperative. While orthovanadate abolished p-nitrophenylphosphatase activity, ouabain inhibition reached 80% (KI=304.9+/-18.3 micromol L-1). The kinetic parameters estimated differ significantly from those for freshwater-acclimated shrimps, suggesting expression of different isoenzymes during salinity adaptation. Despite the approximately 2-fold reduction in K+-phosphatase specific activity, Western blotting analysis revealed similar alpha-subunit expression in gill tissue from shrimps acclimated to 21 per thousand salinity or fresh water, although expression of phosphate-hydrolyzing enzymes other than (Na+,K+)-ATPase was stimulated by high salinity acclimation.
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Affiliation(s)
- N N Mendonça
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Ribeirão Preto 14040-901, SP, Brazil
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Masui DC, Furriel RPM, Silva ECC, Mantelatto FLM, McNamara JC, Barrabin H, Scofano HM, Fontes CFL, Leone FA. Gill microsomal (Na+,K+)-ATPase from the blue crab Callinectes danae: Interactions at cationic sites. Int J Biochem Cell Biol 2005; 37:2521-35. [PMID: 16055367 DOI: 10.1016/j.biocel.2005.06.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2005] [Revised: 05/20/2005] [Accepted: 06/06/2005] [Indexed: 10/25/2022]
Abstract
Euryhaline crustaceans tolerate exposure to a wide range of dilute media, using compensatory, ion regulatory mechanisms. However, data on molecular interactions occurring at cationic sites on the crustacean gill (Na+,K+)-ATPase, a key enzyme in this hyperosmoregulatory process, are unavailable. We report that Na+ binding at the activating site leads to cooperative, heterotropic interactions that are insensitive to K+. The binding of K+ ions to their high affinity sites displaces Na+ ions from their sites. The increase in Na+ ion concentrations increases heterotropic interactions with the K+ ions, with no changes in K0.5 for K+ ion activation at the extracellular sites. Differently from mammalian (Na+,K+)-ATPases, that from C. danae exhibits additional NH4+ ion binding sites that synergistically activate the enzyme at saturating concentrations of Na+ and K+ ions. NH4+ binding is cooperative, and heterotropic NH4+ ion interactions are insensitive to Na+ ions, but Na+ ions displace NH4+ ions from their sites. NH4+ ions also displace Na+ ions from their sites. Mg2+ ions modulate enzyme stimulation by NH4+ ions, displacing NH4+ ion from its sites. These interactions may modulate NH4+ ion excretion and Na+ ion uptake by the gill epithelium in euryhaline crustaceans that confront hyposmotic media.
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Affiliation(s)
- D C Masui
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto 14040-901, SP, Brazil
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Masui DC, Furriel RPM, Mantelatto FLM, McNamara JC, Leone FA. K+-Phosphatase activity of gill (Na+, K+)-ATPase from the blue crab,Callinectes danae: Low-salinity acclimation and expression of the ?-subunit. ACTA ACUST UNITED AC 2005; 303:294-307. [PMID: 15776418 DOI: 10.1002/jez.a.166] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The kinetic properties of a microsomal gill (Na(+), K(+)) ATPase from the blue crab, Callinectes danae, acclimated to 15 per thousand salinity for 10 days, were analyzed using the substrate p-nitrophenylphosphate. The (Na(+), K(+))-ATPase hydrolyzed the substrate obeying Michaelian kinetics at a rate of V=102.9+/-4.3 U.mg(-1) with K(0.5)=1.7+/-0.1 mmol.L(-1), while stimulation by magnesium (V=93.7+/-2.3 U.mg(-1); K(0.5)=1.40+/-0.03 mmol.L(-1)) and potassium ions (V=94.9+/-3.5 U.mg(-1); K(0.5)=2.9+/-0.1 mmol.L(-1)) was cooperative. K(+)-phosphatase activity was also stimulated by ammonium ions to a rate of V=106.2+/-2.2 U. mg(-1) with K(0.5)=9.8+/-0.2 mmol.L(-1), following cooperative kinetics (n(H)=2.9). However, K(+)-phosphatase activity was not stimulated further by K(+) plus NH(4) (+) ions. Sodium ions (K(I)=22.7+/-1.7 mmol.L(-1)), and orthovanadate (K(I)=28.1+/-1.4 nmol.L(-1)) completely inhibited PNPPase activity while ouabain inhibition reached almost 75% (K(I)=142.0+/-7.1 micromol.L(-1)). Western blotting analysis revealed increased expression of the (Na(+), K(+))-ATPase alpha-subunit in crabs acclimated to 15 per thousand salinity compared to those acclimated to 33 per thousand salinity. The increase in (Na(+), K(+))-ATPase activity in C. danae gill tissue in response to low-salinity acclimation apparently derives from the increased expression of the (Na(+), K( (+) ))-ATPase alpha-subunit; phosphate-hydrolyzing enzymes other than (Na(+), K(+))-ATPase are also expressed. These findings allow a better understanding of the kinetic behavior of the enzymes that underlie the osmoregulatory mechanisms of euryhaline crustaceans.
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Affiliation(s)
- D C Masui
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brasil
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Freire CA, Cavassin F, Rodrigues EN, Torres AH, McNamara JC. Adaptive patterns of osmotic and ionic regulation, and the invasion of fresh water by the palaemonid shrimps. Comp Biochem Physiol A Mol Integr Physiol 2003; 136:771-8. [PMID: 14613804 DOI: 10.1016/j.cbpb.2003.08.007] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
To evaluate trends in the osmoregulatory behavior of neotropical, palaemonid shrimps, we investigated osmotic and ionic regulatory patterns in five species of Palaemon or Macrobrachium. The species' life histories depend on saline water to differing degrees, their habitats ranging from the marine/intertidal (P. northropi), through estuaries (P. pandaliformis) to coastal, freshwater streams (M. olfersii, M. potiuna) and inland, continental river systems (M. brasiliense). Hemolymph osmolality, chloride, sodium and magnesium concentrations were measured in shrimps exposed to experimental media ranging from fresh water (<0.5 per thousand ) to concentrated seawater (42 per thousand ) for up to 10 days. The marine and estuarine Palaemon species exhibit well-developed hyper/hypo-osmotic, sodium and chloride regulatory capabilities in mid-range salinities, tending to hyperconform in low salinities. The freshwater Macrobrachium species show variable hyperosmotic, sodium and chloride regulatory capacities, tending to hypoconform or unable to survive at higher salinities. All species hyper-regulate magnesium in fresh water, but hyporegulate strongly in saline media. Palaemonids from the saline habitats show the strongest osmoregulatory capabilities, and fresh water may have been gradually invaded by ancestral species with similar regulatory capacity. However, this regulatory plasticity has been lost to varying degrees in extant freshwater species.
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Affiliation(s)
- Carolina A Freire
- Departamento de Fisiologia, Setor de Ciências Biológicas, Centro Politécnico, Universidade Federal do Paraná, Curitiba, PR 81531-990, Brazil.
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Masui DC, Furriel RPM, Mantelatto FLM, McNamara JC, Leone FA. Gill (Na+,K+)-ATPase from the blue crab Callinectes danae: modulation of K+-phosphatase activity by potassium and ammonium ions. Comp Biochem Physiol B Biochem Mol Biol 2003; 134:631-40. [PMID: 12670789 DOI: 10.1016/s1096-4959(03)00024-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The kinetic properties of a microsomal gill (Na(+),K(+))-ATPase from the blue crab Callinectes danae were analyzed using the substrate p-nitrophenylphosphate. The (Na(+),K(+))-ATPase hydrolyzed PNPP obeying cooperative kinetics (n=1.5) at a rate of V=125.4+/-7.5 U mg(-1) with K(0.5)=1.2+/-0.1 mmol l(-1); stimulation by potassium (V=121.0+/-6.1 U mg(-1); K(0.5)=2.1+/-0.1 mmol l(-1)) and magnesium ions (V=125.3+/-6.3 U mg(-1); K(0.5)=1.0+/-0.1 mmol l(-1)) was cooperative. Ammonium ions also stimulated the enzyme through site-site interactions (n(H)=2.7) to a rate of V=126.1+/-4.8 U mg(-1) with K(0.5)=13.7+/-0.5 mmol l(-1). However, K(+)-phosphatase activity was not stimulated further by K(+) plus NH(4)(+) ions. Sodium ions (K(I)=36.7+/-1.7 mmol l(-1)), ouabain (K(I)=830.3+/-42.5 micromol l(-1)) and orthovanadate (K(I)=34.0+/-1.4 nmol l(-1)) completely inhibited K(+)-phosphatase activity. The competitive inhibition by ATP (K(I)=57.2+/-2.6 micromol l(-1)) of PNPPase activity suggests that both substrates are hydrolyzed at the same site on the enzyme. These data reveal that the K(+)-phosphatase activity corresponds strictly to a (Na(+),K(+))-ATPase in C. danae gill tissue. This is the first known kinetic characterization of K(+)-phosphatase activity in the portunid crab C. danae and should provide a useful tool for comparative studies.
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Affiliation(s)
- D C Masui
- Departamento de Qui;mica, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, SP, Ribeirão Preto, Brazil
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Masui DC, Furriel RPM, McNamara JC, Mantelatto FLM, Leone FA. Modulation by ammonium ions of gill microsomal (Na+,K+)-ATPase in the swimming crab Callinectes danae: a possible mechanism for regulation of ammonia excretion. Comp Biochem Physiol C Toxicol Pharmacol 2002; 132:471-82. [PMID: 12223203 DOI: 10.1016/s1532-0456(02)00110-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The modulation by Na(+), K(+), NH(4)(+) and ATP of the (Na(+),K(+))-ATPase in a microsomal fraction from Callinectes danae gills was analyzed. ATP was hydrolyzed at high-affinity binding sites at a maximal rate of V=35.4+/-2.1 Umg(-1) and K(0.5)=54.0+/-3.6 nM, obeying cooperative kinetics (n(H)=3.6). At low-affinity sites, the enzyme hydrolyzed ATP obeying Michaelis-Menten kinetics with K(M)=55.0+/-3.0 microM and V=271.5+/-17.2 Umg(-1). This is the first demonstration of a crustacean (Na(+),K(+))-ATPase with two ATP hydrolyzing sites. Stimulation by sodium (K(0.5)=5.80+/-0.30 mM), magnesium (K(0.5)=0.48+/-0.02 mM) and potassium ions (K(0.5)=1.61+/-0.06 mM) exhibited site-site interactions, while that by ammonium ions obeyed Michaelis-Menten kinetics (K(M)=4.61+/-0.27 mM). Ouabain (K(I)=147.2+/-7.microM) and orthovanadate (K(I)=11.2+/-0.6 microM) completely inhibited ATPase activity, indicating the absence of contaminating ATPase and/or neutral phosphatase activities. Ammonium and potassium ions synergistically stimulated the enzyme, increasing specific activities up to 90%, suggesting that these ions bind to different sites on the molecule. The presence of each ion modulates enzyme stimulation by the other. The modulation of (Na(+),K(+))-ATPase activity by ammonium ions, and the excretion of NH(4)(+) in benthic crabs are discussed.
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Affiliation(s)
- D C Masui
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirao Preto 14040-901, SP, Brazil
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Furriel RP, McNamara JC, Leone FA. Nitrophenylphosphate as a tool to characterize gill Na(+), K(+)-ATPase activity in hyperregulating Crustacea. Comp Biochem Physiol A Mol Integr Physiol 2001; 130:665-76. [PMID: 11691603 DOI: 10.1016/s1095-6433(01)00400-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The kinetic properties of a gill Na(+), K(+)-ATPase from the freshwater shrimp Macrobrachium olfersii were studied using p-nitrophenylphosphate (PNPP) as a substrate. Sucrose gradient centrifugation of the microsomal fraction revealed a single protein fraction that hydrolyzed PNPP. The Na(+), K(+)-ATPase hydrolyzed PNPP (K(+)-phosphatase activity) obeying Michaelis-Menten kinetics with K(M)=1.72+/-0.06 mmol l(-1) and V(max)=259.1+/-11.6 U mg(-1). ATP was a competitive inhibitor of K(+)-phosphatase activity with a K(i)=50.1+/-2.5 micromol l(-1). A cooperative effect for the stimulation of the enzyme by potassium (K(0.5)=3.62+/-0.18 mmol l(-1); n(H)=1.5) and magnesium ions (K(0.5)=0.61+/-0.02 mmol l(-1), n(H)=1.3) was found. Sodium ions had no effect on K(+)-phosphatase activity up to 1.0 mmol l(-1), but above 80 mmol l(-1) inhibited the original activity by approximately 75%. In the range of 0-10 mmol l(-1), sodium ions did not affect stimulation of the K(+)-phosphatase activity by potassium ions. Ouabain (K(i)=762.4+/-26.7 micromol l(-1)) and orthovanadate (K(i)=0.25+/-0.01 micromol l(-1)) completely inhibited the K(+)-phosphatase activity, while thapsigargin, oligomycin, sodium azide and bafilomycin were without effect. These data demonstrate that the activity measured corresponds to that of the K(+)-phosphatase activity of the Na(+), K(+)-ATPase alone and suggest that the use of PNPP as a substrate to characterize K(+)-phosphatase activity may be a useful technique in comparative osmoregulatory studies of Na(+), K(+)-ATPase activities in crustacean gill tissues, and for consistent comparisons with well known mechanistic properties of the vertebrate enzyme.
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Affiliation(s)
- R P Furriel
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
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Furriel RP, McNamara JC, Leone FA. Characterization of (Na+, K+)-ATPase in gill microsomes of the freshwater shrimp Macrobrachium olfersii. Comp Biochem Physiol B Biochem Mol Biol 2000; 126:303-15. [PMID: 11007172 DOI: 10.1016/s0305-0491(00)00184-x] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To better understand the adaptive strategies that led to freshwater invasion by hyper-regulating Crustacea, we prepared a microsomal (Na+, K+)-ATPase by differential centrifugation of a gill homogenate from the freshwater shrimp Macrobrachium olfersii. Sucrose gradient centrifugation revealed a light fraction containing most of the (Na+, K+)-ATPase activity, contaminated with other ATPases, and a heavy fraction containing negligible (Na+, K+)-ATPase activity. Western blotting showed that M. olfersii gill contains a single alpha-subunit isoform of about 110 kDa. The (Na+, K+)-ATPase hydrolyzed ATP with Michaelis Menten kinetics with K5, = 165+/-5 microM and Vmax = 686.1+/-24.7 U mg(-1). Stimulation by potassium (K0.5 = 2.4+/-0.1 mM) and magnesium ions (K0.5 = 0.76+/-0.03 mM) also obeyed Michaelis-Menten kinetics, while that by sodium ions (K0.5 = 6.0+/-0.2 mM) exhibited site site interactions (n = 1.6). Ouabain (K0.5 = 61.6+/-2.8 microM) and vanadate (K0.5 = 3.2+/-0.1 microM) inhibited up to 70% of the total ATPase activity, while thapsigargin and ethacrynic acid did not affect activity. The remaining 30% activity was inhibited by oligomycin, sodium azide and bafilomycin A. These data suggest that the (Na+, K+)-ATPase corresponds to about 70% of the total ATPase activity; the remaining 30%, i.e. the ouabain-insensitive ATPase activity, apparently correspond to F0F1- and V-ATPases, but not Ca-stimulated and Na- or K-stimulated ATPases. The data confirm the recent invasion of the freshwater biotope by M. olfersii and suggest that (Na+, K+)-ATPase activity may be regulated by the Na+ concentration of the external medium.
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Affiliation(s)
- R P Furriel
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Brazil
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Abstract
The roles of calcium in cell signaling consequent to chromatophorotropin action and as an activator of mechanochemical transport proteins responsible for pigment granule translocation were investigated in the red ovarian chromatosomes of the freshwater shrimp Macrobrachium olfersii. Chromatosomes were perfused with known concentrations of free Ca++ (10(-3) to 10(-9) M) prepared in Mg(++)-EGTA-buffered physiological saline after selectively permeabilizing with 25 microM calcium ionophore A23187 or with 10(-8) M red pigment concentrating hormone (RPCH). The degree of pigment aggregation and the translocation velocity of the leading edges of the pigment mass were recorded in individual chromatosomes during aggregation induced by RPCH or A23187 and dispersion induced by low Ca++. Aggregation is Ca++ dependent, showing a dual extracellular and intracellular requirement. After perfusion with reduced Ca++ (10(-4) to 10(-9) M), RPCH triggers partial aggregation (approximately 65%), although the maximum translocation velocities (approximately 16.5 microns/min) and velocity profiles are unaffected. After aggregation induced at or below 10(-5) M Ca++, spontaneous pigment dispersion ensues, suggesting a Ca++ requirement for RPCH coupling to its receptor, or a concentration-dependent, Ca(++)-induced Ca(++)-release mechanism. The Ca(++)-channel blockers Mn++ (5 mM) and verapamil (50 microM) have no effect on RPCH-triggered aggregation. An intracellular Ca++ requirement for aggregation was demonstrated in chromatosomes in which the Ca++ gradient across the cell membrane was dissipated with A23187. At free [Ca++] above 10(-3) M, aggregation is complete; at 10(-4) M, aggregation is partial, followed by spontaneous dispersion; below 10(-5) M Ca++, pigments do not aggregate but disperse slightly. Aggregation velocities diminish from 11.6 +/- 1.2 microns/min at 5.5 mM Ca++ to 7.4 +/- 1.3 microns/min at 10(-4) M Ca++. Half-maximum aggregation occurs at 3.2 x 10(-5) M Ca++ and half-maximum translocation velocity at 4.8 x 10(-5) M Ca++. Pigment redispersion after 5.5 mM Ca(++)-A23187-induced aggregation is initiated by reducing extracellular Ca++: slight dispersion begins at 10(-7) M, complete dispersion being attained at 10(-9) M Ca++. Dispersion velocities increase from 0.6 +/- 0.2 to 3.1 +/- 0.5 microns/min. Half-maximum dispersion occurs at 7.6 x 10(-9) M Ca++ and half-maximum translocation velocity at 2.9 x 10(-9) M Ca++. These data reveal an extracellular and an intracellular Ca++ requirement for RPCH action, and demonstrate that the centripetal or centrifugal direction of pigment movement, the translocation velocity, and the degree of pigment aggregation or dispersion attained are calcium-dependent properties of the granule translocation apparatus.
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Affiliation(s)
- J C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras, Universidade de São Paulo, Ribeirão Preto, Brazil.
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McNamara JC, Torres AH. Ultracytochemical location of Na(+)/K(+)-atpase activity and effect of high salinity acclimation in gill and renal epithelia of the freshwater shrimp Macrobrachium olfersii (Crustacea, Decapoda). J Exp Zool 1999; 284:617-28. [PMID: 10531548 DOI: 10.1002/(sici)1097-010x(19991101)284:6<617::aid-jez3>3.0.co;2-v] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Accumulation sites of lead phosphate reaction product consequent to Na(+)/K(+)-ATPase activity in gill and renal epithelia of the freshwater shrimp Macrobrachium olfersii were located ultracytochemically by para-nitrophenyl-phosphate hydrolysis and lead precipitation, and quantified per unit membrane area and cytoplasmic volume. In shrimps in freshwater (<0.5 per thousand S, 20 mOsm/kg H(2)O, 0.7 mEq Na(+)/liter), numerous sites of electron-dense, Na(+)/K(+)-ATPase reaction product accumulation were demonstrated in the membrane invaginations of the mitochondria-rich, intralamellar septal cells (12.5 +/- 1.7 sites/microm(2) membrane, 179 +/- 22 sites/microm(3) cytoplasm, mean+/- SEM, N </= 7) and in the basal region of the medial renal tubules (19.8 +/- 1.8 sites/microm(2) membrane, 437 +/- 53 sites/microm(3) cytoplasm), but not in the pillar cells whose apical flanges form the primary interface with the external medium. A putative, ouabain-insensitive Na(+)- or H(+)-ATPase was found in the apical microvilli of the medial renal tubules (17.4 +/- 1.7 sites/microm(2) membrane, 629 +/- 101 sites/microm(3) cytoplasm). This restricted location of Na(+)/K(+)-ATPase activity within the gill epithelium suggests that during uptake, Na(+) moves across the apical pillar cell membrane, passes through specialized, basolateral coupling junctions into the septal cell cytoplasm and is pumped into the hemolymph via the Na(+)/K(+)-ATPase in the invagination membranes. In shrimps acclimated to a high-salinity medium (21 per thousand S, 630 mOsm/kg H(2)O, 280 mEq Na(+)/liter) for 2 and 5 days, the mean number of sites of para-nitrophenylphosphatase activity/microm(2) membrane and /microm(3) cytoplasm for both epithelia increases markedly by 83 and 163%, respectively. However, after 10 days acclimation, the number of sites declines dramatically, attaining values far below those for shrimps in freshwater. These acclimation-induced alterations in numerical density/microm(3) cytoplasm cannot be accounted for by corresponding changes in membrane surface density (microm(2) membrane/microm(3) cytoplasm) and reflect a real alteration in the number of Na(+)/K(+)-ATPase reaction product sites/unit membrane area. These data suggest that neither the gill nor the renal Na(+)/K(+)-ATPase systems function at maximal activity in shrimps in freshwater, possibly due to the low Na(+) concentration, and are initially stimulated by the increase in external ionic concentration. However, these powerful Na(+) transport systems respond to salt loading by a notable reduction in the number of hydrolysis sites, possibly through the incorporation of the Na(+)/K(+)-ATPase into isolated membrane vesicles in the basal invaginations of the medial renal tubules, together with ultrastructural alterations like the spatial isolation of the mitochondria by multiple membrane stacks in the intralamellar septal cells. J. Exp. Zool. 284:617-628, 1999.
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Affiliation(s)
- J C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Sao Paulo, Brasil.
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McNamara JC, Ribeiro MR. Kinetic characterization of pigment migration and the role of the cytoskeleton in granule translocation in the red chromatophores of the shrimpMacrobrachium olfersii (Crustacea, Decapoda). ACTA ACUST UNITED AC 1999. [DOI: 10.1002/(sici)1097-010x(19990101)283:1<19::aid-jez4>3.0.co;2-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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McNamara JC, Lima AG. The Route of Ion and Water Movements Across the Gill Epithelium of the Freshwater Shrimp Macrobrachium olfersii (Decapoda, Palaemonidae): Evidence From Ultrastructural Changes Induced by Acclimation to Saline Media. Biol Bull 1997; 192:321-331. [PMID: 28581864 DOI: 10.2307/1542725] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The ultrastructure of the pillar cells in the gill lamellae of the freshwater shrimp Macrobrachium olfersii was examined to evaluate the routes of salt and water movement across the gill epithelium and into the hemolymph. Alterations were morphometrically quantified in shrimp maintained in fresh water (FW, <0.5{permill} salinity) and after acclimation to saline media (21{permill} or 28{permill} salinity). The tissue interface between the hemolymph and the external medium consists exclusively of the thin apical flange regions of the pillar cells, the upper membrane of which is highly amplified by dense microvilli and overlain by a thin cuticle. The lower flange membrane, bathed by the hemolymph, is smooth and not invaginated. Contiguous flanges are strongly bound by junctional structures including desmosomes and septate junctions. The basal surface of the pillar cell perikaryon is linked to the adjacent septal cells through many basolateral junctions. The septal cell plasmalemma is abundantly and deeply invaginated, each infolding enclosing numerous mitochondria; these characteristics are typical of salt-transporting machinery. After shrimps were acclimated to saline media for 10 days, the thickness of the pillar cell flanges was significantly reduced (from 1.3 to {approx}0.4 {mu}m), as was the height (from 0.8 to 0.3 {mu}m) and density (from 4.0 to {approx} 1.8 microvilli/{mu}m) of the apical microvilli. This reduction in the apical surface area of the pillar cells appears to lead to decreased ionic permeability, concomitant with a reduction in Na+/K+-ATPase activity, thus limiting Na+ uptake. In contrast to the brachyurans, in which the respiratory and ion-transporting mechanisms are differentially located in the anterior and posterior gills, in palaemonid shrimps the pillar cells apparently play a dual role: ions move preferentially through ion transporters in the microvilli above the pillar cell perikaryon, while respiratory gases are exchanged through the fine flange regions in contact with the hemolymph.
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Freire CA, McNamara JC, Rosa JC, Greene LJ. Neuroendocrine control of osmotic regulation in the freshwater shrimp Macrobrachium olfersii (Wiegmann) (Crustacea, decapoda): free amino acid concentrations in the hemolymph. Gen Comp Endocrinol 1995; 100:83-91. [PMID: 8575663 DOI: 10.1006/gcen.1995.1136] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The participation of neuroendocrine factors present within the central nervous system in the regulation of hemolymph free amino acid (FAA) concentrations was examined in the freshwater shrimp Macrobrachium olfersii. Test shrimps were injected intramuscularly with homogenates prepared from the eyestalks (ES), ventral nerve cord (VNC), supraesophageal (SEG), or thoracic ganglia (TG) of donor shrimps previously exposed for 6 hr to a high-salinity medium (HSM, 21% salinity). After injection of the homogenate, the shrimps were maintained for up to 6 hr in either freshwater (FW) or HSM. Hemolymph was sampled by cardiac puncture and prepared for reverse phase HPLC, derivatizing the FAA with phenylisothiocyanate. An FAA profile was determined and the [FAA]:[Cl-] ratios for the four FAA present in highest concentration (Gly, Arg, Ala, and Pro for ES and VNC experiments; Glu, Leu, Ala, and Val for SEG and TG experiments) were obtained. Nonparametric analyses revealed specific, notable effects resulting from homogenate injection, e.g., ES homogenate increased [Pro]/[Cl-] ratios in FW-exposed shrimps; SEG homogenate increased [Glu]/[Cl-] and [Val]/[Cl-] ratios in HSM-exposed shrimps; and TG homogenate increased [FAA]/[Cl-] ratios for Glu, Leu, Ala, and Val in HSM-exposed shrimps. Total FAA concentrations decreased after exposure of the shrimps to HSM but were increased by the injection of ES homogenate in FW-exposed shrimps and by TG homogenate in HSM-exposed shrimps. The total [FAA]/[Cl-] ratio was also increased by TG homogenate in HSM-exposed animals. There were no clear effects on [Cl-] alone.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- C A Freire
- Departamento de Fisiologia Geral, Universidade de Säo Paulo, Brazil
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Freire CA, McNamara JC. Involvement of the central nervous system in neuroendocrine mediation of osmotic and ionic regulation in the freshwater shrimp Macrobrachium olfersii (Crustacea, Decapoda). Gen Comp Endocrinol 1992; 88:316-27. [PMID: 1478447 DOI: 10.1016/0016-6480(92)90265-l] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The presence of putative neurofactors within the central nervous system, i.e., the eyestalks (ES), ventral nerve cord (VNC), and supra-esophageal (SEG) and thoracic ganglia (TG), which are involved in osmotic and ionic regulation, was investigated in the euryhaline, freshwater shrimp, Macrobrachium olfersii. Homogenates were prepared from shrimps exposed for 6 hr to a high salinity medium (HSM, 21/1000 S) and were injected into shrimps subsequently maintained for 1, 3, or 6 hr in freshwater (FW, 0/1000 S) or HSM. Osmolality and sodium, chloride, and calcium concentrations were determined in single hemolymph samples removed at each time interval. Heart rates and wet weights were measured before and after experimental treatments. Exposure to HSM increased [Na+] and [Cl-] and heart rate. Injection of ES homogenate increased osmolality, [Na+] and [Cl-], and wet weight in shrimps maintained in FW; VNC homogenate also increased hemolymph [Cl-] in shrimps maintained in FW after injection, but reduced heart rate in shrimps subsequently exposed to HSM. Injection of TG homogenate reduced heart rate to a lesser extent in shrimps maintained in FW. Hemolymph [Ca2+] was not altered by homogenate injection. The exposure period of 6 hr to HSM appears to result in the accumulation of factors within the central nervous system that regulate the osmotic and ionic concentrations of the hemolymph, in addition to exerting antidiuretic and cardio-depressor actions. The coordinated action of these factors is intimately involved in the hyporegulatory processes that permit the survival of M. olfersii in media of elevated salinity.
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Affiliation(s)
- C A Freire
- Departamento de Fisiologia Geral, Universidade de São Paulo, Brasil
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Scemes E, McNamara JC. The Ultrastructure of the Radial Neuromuscular System of the Jellyfish Liriope tetraphylla (Hydrozoa, Trachymedusae): Implications in Crumpling Behavior. Biol Bull 1991; 181:474-483. [PMID: 29304672 DOI: 10.2307/1542368] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The ultrastructure of the radial neuromuscular system of the trachymedusa Liriope tetraphylla was examined to determine the morphological substrate underlying crumpling behavior--the folding of the margin into the subumbrellar cavity by radial muscle contraction. These contractions are produced by the four smooth muscle bands that run the length of the peduncle and extend over the subumbrellar surface to the margin, along the radii. Axons are present in the radial system and attain appreciable density at the base of insertion of the peduncle; contact between this radial nerve net and the inner nerve ring may occur at the margin. Gap junctions were not encountered within the ectodermal radial system. These various observations are discussed with respect to the control of crumpling in this and other species of hydromedusae.
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McNamara JC, Salomão LC, Ribeiro EA. Neuroendocrine regulation of osmotic and ionic concentrations in the hemolymph of the freshwater shrimp Macrobrachium olfersii (Wiegmann) (Crustacea, Decapoda). Gen Comp Endocrinol 1991; 84:16-26. [PMID: 1778406 DOI: 10.1016/0016-6480(91)90060-j] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Putative neuroendocrine mediation of osmotic and ionic responses to acute exposure to high salinity medium was investigated in the freshwater shrimp Macrobrachium olfersii (Wiegmann). Homogenates of supra-esophageal or thoracic ganglia, prepared from shrimps exposed to seawater of 21% S for 6 hr, were injected into the abdominal musculature of shrimps previously exposed to freshwater and subsequently exposed to either freshwater or seawater (21% S). Osmotic, sodium, chloride, potassium, magnesium, and calcium concentrations were determined in hemolymph samples removed by intracardiac puncture at time = 0, 1, 3, or 6 hr after homogenate application. Control shrimps were injected with filtered seawater, isosmotic to the hemolymph, and treated similarly. In control shrimps, the osmotic, Na+, Cl-, K+, Mg2+, and Ca2+ concentrations in the hemolymph increased (P less than or equal to 0.05) after 1-hr exposure to seawater. In shrimps injected with homogenates of supra-esophageal ganglion and exposed to seawater, osmotic and ionic concentrations in the hemolymph did not vary with exposure time; in injected shrimps exposed to freshwater, Na+, Cl-, K+, and Mg2+ concentrations decreased (P less than or equal to 0.05) with time. In shrimps injected with homogenates of thoracic ganglion and exposed to seawater, hemolymph osmotic, K+, and Mg2+ concentrations increased (P less than or equal to 0.05); Na+, Cl-, and Ca2+ concentrations remained unchanged. In injected shrimps exposed to freshwater, hemolymph osmotic concentration alone increased (P less than or equal to 0.05) after 1 hr, all other ionic concentrations remaining unchanged. These data suggest that neurofactors apparently located within the ganglia of the central nervous system of M. olfersii may alter the apparent ionic permeabilities of this shrimp, depending on the salinity characteristics of the external medium. The data support the notion that invasion of the freshwater biotope by estuarine crustaceans has necessitated the evolution of specific physiological mechanisms capable of compensating for the osmotic dilution and ion loss typically encountered by such organisms.
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Affiliation(s)
- J C McNamara
- Departamento de Biologia, Faculdade de Filosofia, Universidade de São Paulo, Ribeirão Preto, Brasil
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Scemes E, Salomão LC, McNamara JC, Cassola AC. Lack of osmoregulation in Aplysia brasiliana: correlation with response of neuron R15 to osphradial stimulation. Am J Physiol 1991; 260:R777-84. [PMID: 2012248 DOI: 10.1152/ajpregu.1991.260.4.r777] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The exposure of Aplysia brasiliana to dilute seawater (90 and 80%) caused an increase of the relative weight, which returned to the original values after a few hours. Both osmotic and chloride concentrations of the hemolymph decreased on exposure to 80 and 90% dilute seawater, and after 3-h exposure there were no differences between the hemolymph and external media osmotic and chloride concentrations. In contrast to the clear regulatory capabilities reported for A. californica, A. brasiliana cannot maintain the osmolality of its body fluid in dilute media. In A. californica, osphradial receptors and neuron R15 are apparently involved in this regulatory mechanism. Perfusion of osphradium of A. brasiliana with dilute seawater (95-80%) did not affect electrical activity of the bursting neuron R15; perfusion with 70 and 60% seawater caused a transient increase in the duration of the quiescent period. In contrast to the model established for A. californica, in A. brasiliana no relationship was found between exposure of the osphradium to dilute media and electrical activity in neuron R15, which is in accordance with the lack of an osmoregulatory mechanism in this species. Such differences may reflect inherent differences in salinity tolerance between the two species.
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Affiliation(s)
- E Scemes
- Departamento de Fisiologia Geral, Universidade de São Paulo, Brazil
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McNamara JC, Moreira GS, Moreira PS. Thermal effects on metabolism in selected ontogenetic stages of the freshwater shrimps macrobrachium olfersii and macrobrachium heterochirus (decapoda, palaemonidae). ACTA ACUST UNITED AC 1985. [DOI: 10.1016/0300-9629(85)90539-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Moreira GS, McNamara JC, Shumway SE, Moreira PS. Osmoregulation and respiratory metabolism in brazilian Macrobrachium (Decapoda, palaemonidae). ACTA ACUST UNITED AC 1983. [DOI: 10.1016/0300-9629(83)90711-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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