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Fiesinger A, Held C, Schmidt AL, Putchim L, Melzner F, Wall M. Dominance of the coral Pocillopora acuta around Phuket Island in the Andaman Sea, Thailand. Ecol Evol 2023; 13:e10724. [PMID: 38020692 PMCID: PMC10643679 DOI: 10.1002/ece3.10724] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 10/19/2023] [Accepted: 10/30/2023] [Indexed: 12/01/2023] Open
Abstract
Pocillopora damicornis (Linnaeus, 1758), a species complex, consists of several genetic lineages, some of which likely represent reproductively isolated species, including the species Pocillopora acuta Lamarck, 1816. Pocillopora acuta can exhibit similar morphological characteristics as P. damicornis, thus making it difficult to identify species-level taxonomic units. To determine whether the P. damicornis-like colonies on the reefs in the Andaman Sea (previously often identified as P. damicornis) consist of different species, we sampled individual colonies at five sites along a 50 km coastal stretch at Phuket Island and four island sites towards Krabi Province, Thailand. We sequenced 210 coral samples for the mitochondrial open reading frame and identified six distinct haplotypes, all belonging to P. acuta according to the literature. Recently, P. acuta was observed to efficiently recolonize heat-damaged reefs in Thailand as well as globally, making it a potentially important coral species in future reefs. Specifically in the light of global change, this study underscores the importance of high-resolution molecular species recognition, since taxonomic units are important factors for population genetic studies, and the latter are crucial for management and conservation efforts.
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Affiliation(s)
- Anna Fiesinger
- GEOMAR Helmholtz Centre for Ocean Research KielKielGermany
- Department of BiologyUniversity of KonstanzKonstanzGermany
| | - Christoph Held
- Alfred‐Wegener‐InstitutHelmholtz‐Zentrum für Polar‐ und MeeresforschungBremerhavenGermany
| | - Andrea L. Schmidt
- GEOMAR Helmholtz Centre for Ocean Research KielKielGermany
- Cooperative Institute for Marine and Atmospheric ResearchUniversity of Hawai‘i at ManoaHonoluluHonoluluUSA
| | | | - Frank Melzner
- GEOMAR Helmholtz Centre for Ocean Research KielKielGermany
| | - Marlene Wall
- GEOMAR Helmholtz Centre for Ocean Research KielKielGermany
- Alfred‐Wegener‐InstitutHelmholtz‐Zentrum für Polar‐ und MeeresforschungBremerhavenGermany
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2
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Fiesinger A, Held C, Melzner F, Putchim L, Reusch TBH, Schmidt AL, Wall M. Population genetic differentiation of the ubiquitous brooding coral Pocillopora acuta along Phuket Island reefs in the Andaman Sea, Thailand. BMC Ecol Evol 2023; 23:42. [PMID: 37626296 PMCID: PMC10464487 DOI: 10.1186/s12862-023-02153-7] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023] Open
Abstract
BACKGROUND The widespread Indo-Pacific coral species Pocillopora acuta Lamarck, 1816 displays varying levels of asexual versus sexual reproduction, with strong repercussions on genetic diversity, connectivity and genetic structuring within and among populations. For many geographic regions, baseline information on genetic diversity is still lacking, particularly in the Andaman Sea. The region suffered a massive heat-induced bleaching event in 2010 with high coral cover loss of branching coral species such as P. acuta. A subsequent bleaching in 2016, however, revealed a mild bleaching response in pocilloporids compared to other coral taxa in the region, suggesting that rare, heat tolerant genotypes had been selected by the 2010 bleaching event. In order to test whether this potential 'evolutionary rescue' event has led to a low genetic diversity, we conducted a population genetic survey covering a total of nine different P. acuta populations (336 individuals) along a 50 km coastal stretch around Phuket Island, Thailand. We used six microsatellite markers to assess genotypic diversity and to determine the prevalent mode of reproduction (i.e. sexual or asexual recruitment). RESULTS In contrast to other Indian Ocean P. acuta populations, the majority of corals in this study adopted a sexual reproduction mode (75% across all populations). At the same time, substantial regional gene flow was observed around Phuket Island with strong genetic differentiation as indicated by three genetic clusters that were separated by only a few kilometers. Patterns of isolation by distance over 0.7 - 40 km suggest small-scale genetic barriers, such as changing currents throughout each monsoonal season, potentially contributing to locally restricted dispersal of P. acuta larvae. CONCLUSIONS The occurrence of distinct genetic clusters within short coastal stretches suggests that the 2010 bleaching event has not led to extreme genetic impoverishment. While more in-depth genomic analyses are necessary to investigate changes in genetic diversity following extreme bleaching events, our results will help guide conservation efforts to maintain genetic diversity of a coral species that likely will be dominant in future, warmer Andaman Sea reefs.
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Affiliation(s)
- Anna Fiesinger
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Research Unit Experimental Ecology - Benthic Ecology, Wischhofstraße 1-3, 24148, Kiel, Germany.
- Department of Biology, University of Konstanz, Universitätsstraße 10, Konstanz, 78464, Germany.
| | - Christoph Held
- Alfred-Wegener-Institut, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany
| | - Frank Melzner
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Research Unit Experimental Ecology - Benthic Ecology, Wischhofstraße 1-3, 24148, Kiel, Germany
| | - Lalita Putchim
- Phuket Marine Biological Centre, Wichit, Phuket, Mueang Phukt District, 83000, Thailand
| | - Thorsten B H Reusch
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Research Unit Marine Evolutionary Ecoloy, Wischhofstraße 1-3, Kiel, 24148, Germany
| | - Andrea L Schmidt
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Research Unit Experimental Ecology - Benthic Ecology, Wischhofstraße 1-3, 24148, Kiel, Germany
- Cooperative Institute for Marine and Atmospheric Research, University of Hawai'i, Honolulu, HI, 96822, USA
| | - Marlene Wall
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Research Unit Experimental Ecology - Benthic Ecology, Wischhofstraße 1-3, 24148, Kiel, Germany.
- Alfred-Wegener-Institut, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, 27570, Germany.
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3
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Vajedsamiei J, Melzner F, Raatz M, Morón Lugo SC, Pansch C. Cyclic thermal fluctuations can be burden or relief for an ectotherm depending on fluctuations’ average and amplitude. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13889] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jahangir Vajedsamiei
- Department of Marine Ecology GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany
| | - Frank Melzner
- Department of Marine Ecology GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany
| | - Michael Raatz
- Department for Evolutionary Theory Max‐Planck Institute for Evolutionary Biology Plön Germany
| | - Sonia C. Morón Lugo
- Departement des Sciences Fondamentales Universite du Quebec a Chicoutimi 555 Chicoutimi Quebec Canada
| | - Christian Pansch
- Department of Environmental & Marine Biology Åbo Akademi University Turku Finland
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4
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Yarra T, Ramesh K, Blaxter M, Hüning A, Melzner F, Clark MS. Transcriptomic analysis of shell repair and biomineralization in the blue mussel, Mytilus edulis. BMC Genomics 2021; 22:437. [PMID: 34112105 PMCID: PMC8194122 DOI: 10.1186/s12864-021-07751-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [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: 10/20/2020] [Accepted: 05/27/2021] [Indexed: 12/13/2022] Open
Abstract
Background Biomineralization by molluscs involves regulated deposition of calcium carbonate crystals within a protein framework to produce complex biocomposite structures. Effective biomineralization is a key trait for aquaculture, and animal resilience under future climate change. While many enzymes and structural proteins have been identified from the shell and in mantle tissue, understanding biomieralization is impeded by a lack of fundamental knowledge of the genes and pathways involved. In adult bivalves, shells are secreted by the mantle tissue during growth, maintenance and repair, with the repair process, in particular, amenable to experimental dissection at the transcriptomic level in individual animals. Results Gene expression dynamics were explored in the adult blue mussel, Mytilus edulis, during experimentally induced shell repair, using the two valves of each animal as a matched treatment-control pair. Gene expression was assessed using high-resolution RNA-Seq against a de novo assembled database of functionally annotated transcripts. A large number of differentially expressed transcripts were identified in the repair process. Analysis focused on genes encoding proteins and domains identified in shell biology, using a new database of proteins and domains previously implicated in biomineralization in mussels and other molluscs. The genes implicated in repair included many otherwise novel transcripts that encoded proteins with domains found in other shell matrix proteins, as well as genes previously associated with primary shell formation in larvae. Genes with roles in intracellular signalling and maintenance of membrane resting potential were among the loci implicated in the repair process. While haemocytes have been proposed to be actively involved in repair, no evidence was found for this in the M. edulis data. Conclusions The shell repair experimental model and a newly developed shell protein domain database efficiently identified transcripts involved in M. edulis shell production. In particular, the matched pair analysis allowed factoring out of much of the inherent high level of variability between individual mussels. This snapshot of the damage repair process identified a large number of genes putatively involved in biomineralization from initial signalling, through calcium mobilization to shell construction, providing many novel transcripts for future in-depth functional analyses.
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Affiliation(s)
- Tejaswi Yarra
- Ashworth Laboratories, University of Edinburgh, Institute of Evolutionary Biology, Charlotte Auerbach Road, EH9 3FL, Edinburgh, UK.,British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, CB3 0ET, Cambridge, UK
| | - Kirti Ramesh
- GEOMAR Helmholtz Centre for Ocean Research, 24105, Kiel, Germany
| | - Mark Blaxter
- Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, Saffron Walden, UK
| | - Anne Hüning
- GEOMAR Helmholtz Centre for Ocean Research, 24105, Kiel, Germany
| | - Frank Melzner
- GEOMAR Helmholtz Centre for Ocean Research, 24105, Kiel, Germany
| | - Melody S Clark
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, CB3 0ET, Cambridge, UK.
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5
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Clark MS, Peck LS, Arivalagan J, Backeljau T, Berland S, Cardoso JCR, Caurcel C, Chapelle G, De Noia M, Dupont S, Gharbi K, Hoffman JI, Last KS, Marie A, Melzner F, Michalek K, Morris J, Power DM, Ramesh K, Sanders T, Sillanpää K, Sleight VA, Stewart-Sinclair PJ, Sundell K, Telesca L, Vendrami DLJ, Ventura A, Wilding TA, Yarra T, Harper EM. Deciphering mollusc shell production: the roles of genetic mechanisms through to ecology, aquaculture and biomimetics. Biol Rev Camb Philos Soc 2020; 95:1812-1837. [PMID: 32737956 DOI: 10.1111/brv.12640] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 07/17/2020] [Accepted: 07/17/2020] [Indexed: 12/20/2022]
Abstract
Most molluscs possess shells, constructed from a vast array of microstructures and architectures. The fully formed shell is composed of calcite or aragonite. These CaCO3 crystals form complex biocomposites with proteins, which although typically less than 5% of total shell mass, play significant roles in determining shell microstructure. Despite much research effort, large knowledge gaps remain in how molluscs construct and maintain their shells, and how they produce such a great diversity of forms. Here we synthesize results on how shell shape, microstructure, composition and organic content vary among, and within, species in response to numerous biotic and abiotic factors. At the local level, temperature, food supply and predation cues significantly affect shell morphology, whilst salinity has a much stronger influence across latitudes. Moreover, we emphasize how advances in genomic technologies [e.g. restriction site-associated DNA sequencing (RAD-Seq) and epigenetics] allow detailed examinations of whether morphological changes result from phenotypic plasticity or genetic adaptation, or a combination of these. RAD-Seq has already identified single nucleotide polymorphisms associated with temperature and aquaculture practices, whilst epigenetic processes have been shown significantly to modify shell construction to local conditions in, for example, Antarctica and New Zealand. We also synthesize results on the costs of shell construction and explore how these affect energetic trade-offs in animal metabolism. The cellular costs are still debated, with CaCO3 precipitation estimates ranging from 1-2 J/mg to 17-55 J/mg depending on experimental and environmental conditions. However, organic components are more expensive (~29 J/mg) and recent data indicate transmembrane calcium ion transporters can involve considerable costs. This review emphasizes the role that molecular analyses have played in demonstrating multiple evolutionary origins of biomineralization genes. Although these are characterized by lineage-specific proteins and unique combinations of co-opted genes, a small set of protein domains have been identified as a conserved biomineralization tool box. We further highlight the use of sequence data sets in providing candidate genes for in situ localization and protein function studies. The former has elucidated gene expression modularity in mantle tissue, improving understanding of the diversity of shell morphology synthesis. RNA interference (RNAi) and clustered regularly interspersed short palindromic repeats - CRISPR-associated protein 9 (CRISPR-Cas9) experiments have provided proof of concept for use in the functional investigation of mollusc gene sequences, showing for example that Pif (aragonite-binding) protein plays a significant role in structured nacre crystal growth and that the Lsdia1 gene sets shell chirality in Lymnaea stagnalis. Much research has focused on the impacts of ocean acidification on molluscs. Initial studies were predominantly pessimistic for future molluscan biodiversity. However, more sophisticated experiments incorporating selective breeding and multiple generations are identifying subtle effects and that variability within mollusc genomes has potential for adaption to future conditions. Furthermore, we highlight recent historical studies based on museum collections that demonstrate a greater resilience of molluscs to climate change compared with experimental data. The future of mollusc research lies not solely with ecological investigations into biodiversity, and this review synthesizes knowledge across disciplines to understand biomineralization. It spans research ranging from evolution and development, through predictions of biodiversity prospects and future-proofing of aquaculture to identifying new biomimetic opportunities and societal benefits from recycling shell products.
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Affiliation(s)
- Melody S Clark
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, U.K
| | - Lloyd S Peck
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, U.K
| | - Jaison Arivalagan
- UMR 7245 CNRS/MNHN Molécules de Communications et Adaptations des Micro-organismes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Paris, France.,Proteomics Center of Excellence, Northwestern University, 710 N Fairbanks Ct, Chicago, IL, U.S.A
| | - Thierry Backeljau
- Royal Belgian Institute of Natural Sciences, Rue Vautier 29, Brussels, B-1000, Belgium.,Evolutionary Ecology Group, University of Antwerp, Universiteitsplein 1, Antwerp, B-2610, Belgium
| | - Sophie Berland
- UMR 7208 CNRS/MNHN/UPMC/IRD Biologie des Organismes Aquatiques et Ecosystèmes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Paris, France
| | - Joao C R Cardoso
- Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, Faro, 8005-139, Portugal
| | - Carlos Caurcel
- Ashworth Laboratories, Institute of Evolutionary Biology, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, U.K
| | - Gauthier Chapelle
- Royal Belgian Institute of Natural Sciences, Rue Vautier 29, Brussels, B-1000, Belgium
| | - Michele De Noia
- Department of Animal Behavior, University of Bielefeld, Postfach 100131, Bielefeld, 33615, Germany.,Institute of Biodiversity Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, U.K
| | - Sam Dupont
- Department of Biological and Environmental Sciences, University of Göteburg, Box 463, Göteburg, SE405 30, Sweden
| | - Karim Gharbi
- Ashworth Laboratories, Institute of Evolutionary Biology, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, U.K
| | - Joseph I Hoffman
- Department of Animal Behavior, University of Bielefeld, Postfach 100131, Bielefeld, 33615, Germany
| | - Kim S Last
- Scottish Association for Marine Science, Scottish Marine Institute, Oban, Argyll, PA37 1QA, U.K
| | - Arul Marie
- UMR 7245 CNRS/MNHN Molécules de Communications et Adaptations des Micro-organismes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Paris, France
| | - Frank Melzner
- GEOMAR Helmholtz Centre for Ocean Research, Kiel, 24105, Germany
| | - Kati Michalek
- Scottish Association for Marine Science, Scottish Marine Institute, Oban, Argyll, PA37 1QA, U.K
| | - James Morris
- Royal Belgian Institute of Natural Sciences, Rue Vautier 29, Brussels, B-1000, Belgium
| | - Deborah M Power
- Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, Faro, 8005-139, Portugal
| | - Kirti Ramesh
- GEOMAR Helmholtz Centre for Ocean Research, Kiel, 24105, Germany
| | - Trystan Sanders
- GEOMAR Helmholtz Centre for Ocean Research, Kiel, 24105, Germany
| | - Kirsikka Sillanpää
- Swemarc, Department of Biological and Environmental Science, University of Gothenburg, Box 463, Gothenburg, SE405 30, Sweden
| | - Victoria A Sleight
- School of Biological Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen, AB24 2TZ, U.K
| | | | - Kristina Sundell
- Swemarc, Department of Biological and Environmental Science, University of Gothenburg, Box 463, Gothenburg, SE405 30, Sweden
| | - Luca Telesca
- Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, U.K
| | - David L J Vendrami
- Department of Animal Behavior, University of Bielefeld, Postfach 100131, Bielefeld, 33615, Germany
| | - Alexander Ventura
- Department of Biological and Environmental Sciences, University of Göteburg, Box 463, Göteburg, SE405 30, Sweden
| | - Thomas A Wilding
- Scottish Association for Marine Science, Scottish Marine Institute, Oban, Argyll, PA37 1QA, U.K
| | - Tejaswi Yarra
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, U.K.,Ashworth Laboratories, Institute of Evolutionary Biology, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL, U.K
| | - Elizabeth M Harper
- Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, U.K
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Abstract
Ocean warming impacts the fitness of marine ectothermic species, leading to poleward range shifts, re-shuffling of communities, and changes in ecosystem services. While the detrimental effects of summer heat waves have been widely studied, little is known about the impacts of winter warming on marine species in temperate regions. Many species benefit from low winter temperature-induced reductions in metabolism, as these permit conservation of energy reserves that are needed to support reproduction in spring. Here, we used a unique outdoor mesocosm system to expose a coastal predator-prey system, the sea star Asterias and the blue mussel Mytilus, to different winter warming scenarios under near-natural conditions. We found that the body condition of mussels decreased in a linear fashion with increasing temperature. Sea star growth also decreased with increasing temperature, which was a function of unaltered predation rates and decreased mussel body condition. Asterias relative digestive gland mass strongly declined over the studied temperature interval (ca twofold). This could have severe implications for reproductive capacity in the following spring, as digestive glands provide reserve compounds to maturing gonads. Thus, both predator and prey suffered from a mismatch of energy acquisition versus consumption in warmer winter scenarios, with pronounced consequences for food web energy transfer in future oceans.
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Affiliation(s)
- Frank Melzner
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Hohenbergstrasse 2, 24105 Kiel, Germany.,Christian-Albrechts-Universität zu Kiel, Germany
| | - Björn Buchholz
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Hohenbergstrasse 2, 24105 Kiel, Germany
| | - Fabian Wolf
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Hohenbergstrasse 2, 24105 Kiel, Germany
| | - Ulrike Panknin
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Hohenbergstrasse 2, 24105 Kiel, Germany
| | - Marlene Wall
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Hohenbergstrasse 2, 24105 Kiel, Germany
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7
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Knöbel L, Breusing C, Bayer T, Sharma V, Hiller M, Melzner F, Stuckas H. Comparative de novo assembly and annotation of mantle tissue transcriptomes from the Mytilus edulis species complex (M. edulis, M. galloprovincialis, M. trossulus). Mar Genomics 2020. [DOI: 10.1016/j.margen.2019.100700] [Citation(s) in RCA: 10] [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] [Indexed: 11/24/2022]
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Abstract
In the last few decades, numerous studies have investigated the impacts of simulated ocean acidification on marine species and communities, particularly those inhabiting dynamic coastal systems. Despite these research efforts, there are many gaps in our understanding, particularly with respect to physiological mechanisms that lead to pathologies. In this review, we trace how carbonate system disturbances propagate from the coastal environment into marine invertebrates and highlight mechanistic links between these disturbances and organism function. We also point toward several processes related to basic invertebrate biology that are severely understudied and prevent an accurate understanding of how carbonate system dynamics influence organismic homeostasis and fitness-related traits. We recommend that significant research effort be directed to studying cellular phenotypes of invertebrates acclimated or adapted to elevated seawater pCO2 using biochemical and physiological methods.
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Affiliation(s)
- Frank Melzner
- Marine Ecology Research Division, GEOMAR Helmholtz Centre for Ocean Research Kiel, 24105 Kiel, Germany;
| | - Felix C Mark
- Department of Integrative Ecophysiology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany;
| | - Brad A Seibel
- College of Marine Science, University of South Florida, St. Petersburg, Florida 33701, USA;
| | - Lars Tomanek
- Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, California 93407, USA;
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9
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Ramesh K, Melzner F, Griffith AW, Gobler CJ, Rouger C, Tasdemir D, Nehrke G. In vivo characterization of bivalve larval shells: a confocal Raman microscopy study. J R Soc Interface 2019; 15:rsif.2017.0723. [PMID: 29643222 DOI: 10.1098/rsif.2017.0723] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 03/16/2018] [Indexed: 11/12/2022] Open
Abstract
In vivo confocal Raman microscopy (CRM), polarized light microscopy and Fourier transform infrared spectroscopy (FTIR) were used to determine if a significant amount of amorphous calcium carbonate (ACC) exists within larval shells of Baltic mytilid mussels (Mytilus edulis-like) and whether the amount of ACC varies during larval development. No evidence for ACC was found from the onset of shell deposition at 21 h post-fertilization (hpf) until 48 hpf. Larval Mytilus shells were crystalline from 21 hpf onwards and exhibited CRM and FTIR peaks characteristic of aragonite. Prior to shell deposition at 21 hpf, no evidence for carbonates was observed through in vivo CRM. We further analysed the composition of larval shells in three other bivalve species, Mercenaria mercenaria, Crassostrea gigas and Crassostrea virginica and observed no evidence for ACC, which is in contrast to previous work on the same species. Our findings indicate that larval bivalve shells are composed of crystalline aragonite and we demonstrate that conflicting results are related to sub-optimal measurements and misinterpretation of CRM spectra. Our results demonstrate that the common perception that ACC generally occurs as a stable and abundant precursor during larval bivalve calcification needs to be critically reviewed.
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Affiliation(s)
- Kirti Ramesh
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany
| | - Frank Melzner
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany
| | - Andrew W Griffith
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
| | - Christopher J Gobler
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
| | - Caroline Rouger
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany
| | - Deniz Tasdemir
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany
| | - Gernot Nehrke
- Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, Bremerhaven, Germany
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10
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Ramesh K, Yarra T, Clark MS, John U, Melzner F. Expression of calcification-related ion transporters during blue mussel larval development. Ecol Evol 2019; 9:7157-7172. [PMID: 31380040 PMCID: PMC6662379 DOI: 10.1002/ece3.5287] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [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: 10/30/2018] [Revised: 05/06/2019] [Accepted: 05/08/2019] [Indexed: 01/03/2023] Open
Abstract
The physiological processes driving the rapid rates of calcification in larval bivalves are poorly understood. Here, we use a calcification substrate-limited approach (low dissolved inorganic carbon, C T) and mRNA sequencing to identify proteins involved in bicarbonate acquisition during shell formation. As a secondary approach, we examined expression of ion transport and shell matrix proteins (SMPs) over the course of larval development and shell formation. We reared four families of Mytilus edulis under ambient (ca. 1865 µmol/kg) and low C T (ca. 941 µmol/kg) conditions and compared expression patterns at six developmental time points. Larvae reared under low C T exhibited a developmental delay, and a small subset of contigs was differentially regulated between ambient and low C T conditions. Of particular note was the identification of one contig encoding an anion transporter (SLC26) which was strongly upregulated (2.3-2.9 fold) under low C T conditions. By analyzing gene expression profiles over the course of larval development, we are able to isolate sequences encoding ion transport and SMPs to enhance our understanding of cellular pathways underlying larval calcification processes. In particular, we observe the differential expression of contigs encoding SLC4 family members (sodium bicarbonate cotransporters, anion exchangers), calcium-transporting ATPases, sodium/calcium exchangers, and SMPs such as nacrein, tyrosinase, and transcripts related to chitin production. With a range of candidate genes, this work identifies ion transport pathways in bivalve larvae and by applying comparative genomics to investigate temporal expression patterns, provides a foundation for further studies to functionally characterize the proteins involved in larval calcification.
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Affiliation(s)
- Kirti Ramesh
- GEOMAR Helmholtz Centre for Ocean ResearchKielGermany
- Department of Biological and Environmental Sciences, Sven Lovén Centre for Marine Infrastructure‐KristinebergUniversity of GothenburgFiskebäckskilSweden
| | - Tejaswi Yarra
- British Antarctic SurveyNatural Environment Research CouncilCambridgeUK
- Ashworth Laboratories, Institute of Evolutionary BiologyUniversity of EdinburghEdinburghUK
| | - Melody S. Clark
- British Antarctic SurveyNatural Environment Research CouncilCambridgeUK
| | - Uwe John
- Ecological ChemistryAlfred‐Wegener‐Institut Helmholtz‐Zentrum für Polar‐und MeeresforschungBremerhavenGermany
- Helmholtz‐Institute for Functional Marine BiodiversityOldenburgGermany
| | - Frank Melzner
- GEOMAR Helmholtz Centre for Ocean ResearchKielGermany
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11
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Hu MY, Lein E, Bleich M, Melzner F, Stumpp M. Trans-life cycle acclimation to experimental ocean acidification affects gastric pH homeostasis and larval recruitment in the sea star Asterias rubens. Acta Physiol (Oxf) 2018; 224:e13075. [PMID: 29660255 DOI: 10.1111/apha.13075] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 03/28/2018] [Accepted: 04/07/2018] [Indexed: 12/12/2022]
Abstract
AIM Experimental simulation of near-future ocean acidification (OA) has been demonstrated to affect growth and development of echinoderm larval stages through energy allocation towards ion and pH compensatory processes. To date, it remains largely unknown how major pH regulatory systems and their energetics are affected by trans-generational exposure to near-future acidification levels. METHODS Here, we used the common sea star Asterias rubens in a reciprocal transplant experiment comprising different combinations of OA scenarios, to study trans-generational plasticity using morphological and physiological endpoints. RESULTS Acclimation of adults to pHT 7.2 (pCO2 3500 μatm) led to reductions in feeding rates, gonad weight and fecundity. No effects were evident at moderate acidification levels (pHT 7.4; pCO2 2000 μatm). Parental pre-acclimation to pHT 7.2 for 85 days reduced developmental rates even when larvae were raised under moderate and high pH conditions, whereas pre-acclimation to pHT 7.4 did not alter offspring performance. Microelectrode measurements and pharmacological inhibitor studies carried out on larval stages demonstrated that maintenance of alkaline gastric pH represents a substantial energy sink under acidified conditions that may contribute up to 30% to the total energy budget. CONCLUSION Parental pre-acclimation to acidification levels that are beyond the pH that is encountered by this population in its natural habitat (eg, pHT 7.2) negatively affected larval size and development, potentially through reduced energy transfer. Maintenance of alkaline gastric pH and reductions in maternal energy reserves probably constitute the main factors for a reduced juvenile recruitment of this marine keystone species under simulated OA.
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Affiliation(s)
- M. Y. Hu
- Institute of Physiology; Christian-Albrechts-University Kiel; Kiel Germany
| | - E. Lein
- Department of Collective Behaviour; Max Planck Institute for Ornithology; Radolfzell Germany
- Helmholtz Centre for Ocean Research Kiel (GEOMAR); Kiel Germany
| | - M. Bleich
- Institute of Physiology; Christian-Albrechts-University Kiel; Kiel Germany
| | - F. Melzner
- Helmholtz Centre for Ocean Research Kiel (GEOMAR); Kiel Germany
| | - M. Stumpp
- Institute of Zoology; Comparative Immunobiology; Christian-Albrechts-University Kiel; Kiel Germany
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12
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Reusch TBH, Dierking J, Andersson HC, Bonsdorff E, Carstensen J, Casini M, Czajkowski M, Hasler B, Hinsby K, Hyytiäinen K, Johannesson K, Jomaa S, Jormalainen V, Kuosa H, Kurland S, Laikre L, MacKenzie BR, Margonski P, Melzner F, Oesterwind D, Ojaveer H, Refsgaard JC, Sandström A, Schwarz G, Tonderski K, Winder M, Zandersen M. The Baltic Sea as a time machine for the future coastal ocean. Sci Adv 2018; 4:eaar8195. [PMID: 29750199 PMCID: PMC5942908 DOI: 10.1126/sciadv.aar8195] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 03/27/2018] [Indexed: 05/21/2023]
Abstract
Coastal global oceans are expected to undergo drastic changes driven by climate change and increasing anthropogenic pressures in coming decades. Predicting specific future conditions and assessing the best management strategies to maintain ecosystem integrity and sustainable resource use are difficult, because of multiple interacting pressures, uncertain projections, and a lack of test cases for management. We argue that the Baltic Sea can serve as a time machine to study consequences and mitigation of future coastal perturbations, due to its unique combination of an early history of multistressor disturbance and ecosystem deterioration and early implementation of cross-border environmental management to address these problems. The Baltic Sea also stands out in providing a strong scientific foundation and accessibility to long-term data series that provide a unique opportunity to assess the efficacy of management actions to address the breakdown of ecosystem functions. Trend reversals such as the return of top predators, recovering fish stocks, and reduced input of nutrient and harmful substances could be achieved only by implementing an international, cooperative governance structure transcending its complex multistate policy setting, with integrated management of watershed and sea. The Baltic Sea also demonstrates how rapidly progressing global pressures, particularly warming of Baltic waters and the surrounding catchment area, can offset the efficacy of current management approaches. This situation calls for management that is (i) conservative to provide a buffer against regionally unmanageable global perturbations, (ii) adaptive to react to new management challenges, and, ultimately, (iii) multisectorial and integrative to address conflicts associated with economic trade-offs.
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Affiliation(s)
- Thorsten B. H. Reusch
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Marine Ecology, Germany
- Corresponding author.
| | - Jan Dierking
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Marine Ecology, Germany
| | | | | | | | - Michele Casini
- Department of Aquatic Resources, Institute of Marine Research, Swedish University of Agricultural Sciences, Lysekil, Sweden
| | | | - Berit Hasler
- Department of Environmental Science, Aarhus University, Roskilde, Denmark
| | - Klaus Hinsby
- Geological Survey of Denmark and Greenland, Copenhagen, Denmark
| | | | | | - Seifeddine Jomaa
- Department of Aquatic Ecosystem Analysis and Management, Helmholtz Centre for Environmental Research-UFZ Magdeburg, Germany
| | | | - Harri Kuosa
- Finnish Environment Institute (SYKE), Helsinki, Finland
| | - Sara Kurland
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Linda Laikre
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Brian R. MacKenzie
- National Institute of Aquatic Resources, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Piotr Margonski
- National Marine Fisheries Research Institute, Gdynia, Poland
| | - Frank Melzner
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Marine Ecology, Germany
| | - Daniel Oesterwind
- Thuenen Institute–Institute of Baltic Sea Fisheries, Rostock, Germany
| | - Henn Ojaveer
- Estonian Marine Institute, University of Tartu, Tartu, Estonia
| | | | | | - Gerald Schwarz
- Thuenen Institute of Farm Economics, Braunschweig, Germany
| | | | - Monika Winder
- Department of Ecology, Environment, and Plant Sciences, Stockholm University, Stockholm, Sweden
| | - Marianne Zandersen
- Department of Environmental Science, Aarhus University, Roskilde, Denmark
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13
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Stuckas H, Knöbel L, Schade H, Breusing C, Hinrichsen HH, Bartel M, Langguth K, Melzner F. Combining hydrodynamic modelling with genetics: can passive larval drift shape the genetic structure of Baltic Mytilus populations? Mol Ecol 2017; 26:2765-2782. [PMID: 28238204 DOI: 10.1111/mec.14075] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/28/2017] [Accepted: 01/30/2017] [Indexed: 11/30/2022]
Abstract
While secondary contact between Mytilus edulis and Mytilus trossulus in North America results in mosaic hybrid zone formation, both species form a hybrid swarm in the Baltic. Despite pervasive gene flow, Baltic Mytilus species maintain substantial genetic and phenotypic differentiation. Exploring mechanisms underlying the contrasting genetic composition in Baltic Mytilus species will allow insights into processes such as speciation or adaptation to extremely low salinity. Previous studies in the Baltic indicated that only weak interspecific reproductive barriers exist and discussed the putative role of adaptation to environmental conditions. Using a combination of hydrodynamic modelling and multilocus genotyping, we investigate how oceanographic conditions influence passive larval dispersal and hybrid swarm formation in the Baltic. By combining our analyses with previous knowledge, we show a genetic transition of Baltic Mytilus species along longitude 12°-13°E, that is a virtual line between Malmö (Sweden) and Stralsund (Germany). Although larval transport only occurs over short distances (10-30 km), limited larval dispersal could not explain the position of this genetic transition zone. Instead, the genetic transition zone is located at the area of maximum salinity change (15-10 psu). Thus, we argue that selection results in weak reproductive barriers and local adaptation. This scenario could maintain genetic and phenotypic differences between Baltic Mytilus species despite pervasive introgressive hybridization.
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Affiliation(s)
- Heiko Stuckas
- Population Genetics, Museum of Zoology, Senckenberg Natural History Collections Dresden, Königsbrücker Landstrasse 159, 01109, Dresden, Germany
| | - Loreen Knöbel
- Population Genetics, Museum of Zoology, Senckenberg Natural History Collections Dresden, Königsbrücker Landstrasse 159, 01109, Dresden, Germany
| | - Hanna Schade
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research, Düsternbrooker Weg 20, 24105, Kiel, Germany
| | - Corinna Breusing
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research, Düsternbrooker Weg 20, 24105, Kiel, Germany.,Evolutionary Ecology of Marine Fishes, Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research, Düsternbrooker Weg 20, 24105, Kiel, Germany
| | - Hans-Harald Hinrichsen
- Evolutionary Ecology of Marine Fishes, Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research, Düsternbrooker Weg 20, 24105, Kiel, Germany
| | - Manuela Bartel
- Population Genetics, Museum of Zoology, Senckenberg Natural History Collections Dresden, Königsbrücker Landstrasse 159, 01109, Dresden, Germany
| | - Klaudia Langguth
- Population Genetics, Museum of Zoology, Senckenberg Natural History Collections Dresden, Königsbrücker Landstrasse 159, 01109, Dresden, Germany
| | - Frank Melzner
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research, Düsternbrooker Weg 20, 24105, Kiel, Germany
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14
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Thomsen J, Stapp LS, Haynert K, Schade H, Danelli M, Lannig G, Wegner KM, Melzner F. Naturally acidified habitat selects for ocean acidification-tolerant mussels. Sci Adv 2017; 3:e1602411. [PMID: 28508039 PMCID: PMC5406135 DOI: 10.1126/sciadv.1602411] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 02/28/2017] [Indexed: 05/19/2023]
Abstract
Ocean acidification severely affects bivalves, especially their larval stages. Consequently, the fate of this ecologically and economically important group depends on the capacity and rate of evolutionary adaptation to altered ocean carbonate chemistry. We document successful settlement of wild mussel larvae (Mytilus edulis) in a periodically CO2-enriched habitat. The larval fitness of the population originating from the CO2-enriched habitat was compared to the response of a population from a nonenriched habitat in a common garden experiment. The high CO2-adapted population showed higher fitness under elevated Pco2 (partial pressure of CO2) than the non-adapted cohort, demonstrating, for the first time, an evolutionary response of a natural mussel population to ocean acidification. To assess the rate of adaptation, we performed a selection experiment over three generations. CO2 tolerance differed substantially between the families within the F1 generation, and survival was drastically decreased in the highest, yet realistic, Pco2 treatment. Selection of CO2-tolerant F1 animals resulted in higher calcification performance of F2 larvae during early shell formation but did not improve overall survival. Our results thus reveal significant short-term selective responses of traits directly affected by ocean acidification and long-term adaptation potential in a key bivalve species. Because immediate response to selection did not directly translate into increased fitness, multigenerational studies need to take into consideration the multivariate nature of selection acting in natural habitats. Combinations of short-term selection with long-term adaptation in populations from CO2-enriched versus nonenriched natural habitats represent promising approaches for estimating adaptive potential of organisms facing global change.
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Affiliation(s)
- Jörn Thomsen
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany
- Corresponding author.
| | - Laura S. Stapp
- Integrative Ecophysiology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany
- University of Bremen, 28359 Bremen, Germany
| | - Kristin Haynert
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany
- Marine Research Department, Senckenberg am Meer, 26382 Wilhelmshaven, Germany
| | - Hanna Schade
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany
| | - Maria Danelli
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany
| | - Gisela Lannig
- Integrative Ecophysiology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany
| | - K. Mathias Wegner
- Coastal Ecology, Wadden Sea Station Sylt, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 25992 List/Sylt, Germany
| | - Frank Melzner
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany
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15
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Stapp LS, Thomsen J, Schade H, Bock C, Melzner F, Pörtner HO, Lannig G. Intra-population variability of ocean acidification impacts on the physiology of Baltic blue mussels (Mytilus edulis): integrating tissue and organism response. J Comp Physiol B 2016; 187:529-543. [PMID: 27921142 DOI: 10.1007/s00360-016-1053-6] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 11/08/2016] [Accepted: 11/23/2016] [Indexed: 01/08/2023]
Abstract
Increased maintenance costs at cellular, and consequently organism level, are thought to be involved in shaping the sensitivity of marine calcifiers to ocean acidification (OA). Yet, knowledge of the capacity of marine calcifiers to undergo metabolic adaptation is sparse. In Kiel Fjord, blue mussels thrive despite periodically high seawater PCO2, making this population interesting for studying metabolic adaptation under OA. Consequently, we conducted a multi-generation experiment and compared physiological responses of F1 mussels from 'tolerant' and 'sensitive' families exposed to OA for 1 year. Family classifications were based on larval survival; tolerant families settled at all PCO2 levels (700, 1120, 2400 µatm) while sensitive families did not settle at the highest PCO2 (≥99.8% mortality). We found similar filtration rates between family types at the control and intermediate PCO2 level. However, at 2400 µatm, filtration and metabolic scope of gill tissue decreased in tolerant families, indicating functional limitations at the tissue level. Routine metabolic rates (RMR) and summed tissue respiration (gill and outer mantle tissue) of tolerant families were increased at intermediate PCO2, indicating elevated cellular homeostatic costs in various tissues. By contrast, OA did not affect tissue and routine metabolism of sensitive families. However, tolerant mussels were characterised by lower RMR at control PCO2 than sensitive families, which had variable RMR. This might provide the energetic scope to cover increased energetic demands under OA, highlighting the importance of analysing intra-population variability. The mechanisms shaping such difference in RMR and scope, and thus species' adaptation potential, remain to be identified.
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Affiliation(s)
- L S Stapp
- Integrative Ecophysiology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany. .,University of Bremen, NW2, Leobener Strasse, 28359, Bremen, Germany.
| | - J Thomsen
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research, Hohenbergstrasse 2, 24105, Kiel, Germany
| | - H Schade
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research, Hohenbergstrasse 2, 24105, Kiel, Germany.,Marine Biology, Faculty of Mathematics and Natural Sciences (MNF), Rostock University, Albert-Einstein-Straße 3, 18059, Rostock, Germany
| | - C Bock
- Integrative Ecophysiology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
| | - F Melzner
- Marine Ecology, GEOMAR Helmholtz Centre for Ocean Research, Hohenbergstrasse 2, 24105, Kiel, Germany
| | - H O Pörtner
- Integrative Ecophysiology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany.,University of Bremen, NW2, Leobener Strasse, 28359, Bremen, Germany
| | - G Lannig
- Integrative Ecophysiology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
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16
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Breusing C, Biastoch A, Drews A, Metaxas A, Jollivet D, Vrijenhoek RC, Bayer T, Melzner F, Sayavedra L, Petersen JM, Dubilier N, Schilhabel MB, Rosenstiel P, Reusch TBH. Biophysical and Population Genetic Models Predict the Presence of "Phantom" Stepping Stones Connecting Mid-Atlantic Ridge Vent Ecosystems. Curr Biol 2016; 26:2257-67. [PMID: 27476600 DOI: 10.1016/j.cub.2016.06.062] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 06/26/2016] [Accepted: 06/28/2016] [Indexed: 12/13/2022]
Abstract
Deep-sea hydrothermal vents are patchily distributed ecosystems inhabited by specialized animal populations that are textbook meta-populations. Many vent-associated species have free-swimming, dispersive larvae that can establish connections between remote populations. However, connectivity patterns among hydrothermal vents are still poorly understood because the deep sea is undersampled, the molecular tools used to date are of limited resolution, and larval dispersal is difficult to measure directly. A better knowledge of connectivity is urgently needed to develop sound environmental management plans for deep-sea mining. Here, we investigated larval dispersal and contemporary connectivity of ecologically important vent mussels (Bathymodiolus spp.) from the Mid-Atlantic Ridge by using high-resolution ocean modeling and population genetic methods. Even when assuming a long pelagic larval duration, our physical model of larval drift suggested that arrival at localities more than 150 km from the source site is unlikely and that dispersal between populations requires intermediate habitats ("phantom" stepping stones). Dispersal patterns showed strong spatiotemporal variability, making predictions of population connectivity challenging. The assumption that mussel populations are only connected via additional stepping stones was supported by contemporary migration rates based on neutral genetic markers. Analyses of population structure confirmed the presence of two southern and two hybridizing northern mussel lineages that exhibited a substantial, though incomplete, genetic differentiation. Our study provides insights into how vent animals can disperse between widely separated vent habitats and shows that recolonization of perturbed vent sites will be subject to chance events, unless connectivity is explicitly considered in the selection of conservation areas.
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Affiliation(s)
- Corinna Breusing
- GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany.
| | - Arne Biastoch
- GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
| | - Annika Drews
- GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
| | - Anna Metaxas
- Department of Oceanography, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Didier Jollivet
- CNRS, Sorbonne Universités, UMR 7144 CNRS-UPMC, Adaptation et Diversité en Milieu Marin, Équipe ABICE, Station Biologique de Roscoff, 29688 Roscoff Cedex, France
| | | | - Till Bayer
- GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
| | - Frank Melzner
- GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany
| | - Lizbeth Sayavedra
- Symbiosis Department, Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany
| | - Jillian M Petersen
- Symbiosis Department, Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany; Department of Microbiology and Ecosystem Science, University of Vienna, 1090 Vienna, Austria
| | - Nicole Dubilier
- Symbiosis Department, Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany
| | - Markus B Schilhabel
- Institute of Clinical Molecular Biology (IKMB), Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
| | - Philip Rosenstiel
- Institute of Clinical Molecular Biology (IKMB), Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
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17
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Hüning AK, Lange SM, Ramesh K, Jacob DE, Jackson DJ, Panknin U, Gutowska MA, Philipp EE, Rosenstiel P, Lucassen M, Melzner F. A shell regeneration assay to identify biomineralization candidate genes in mytilid mussels. Mar Genomics 2016; 27:57-67. [DOI: 10.1016/j.margen.2016.03.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 03/28/2016] [Accepted: 03/30/2016] [Indexed: 11/29/2022]
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18
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Sillanpää J, Ramesh K, Melzner F, Sundh H, Sundell K. Calcium mobilisation following shell damage in the Pacific oyster, Crassostrea gigas. Mar Genomics 2016; 27:75-83. [DOI: 10.1016/j.margen.2016.03.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/18/2016] [Accepted: 03/02/2016] [Indexed: 10/22/2022]
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19
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Thomsen J, Casties I, Pansch C, Körtzinger A, Melzner F. Food availability outweighs ocean acidification effects in juvenile Mytilus edulis: laboratory and field experiments. Glob Chang Biol 2013; 19:1017-27. [PMID: 23504880 DOI: 10.1111/gcb.12109] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Accepted: 11/14/2012] [Indexed: 05/22/2023]
Abstract
Ocean acidification is expected to decrease calcification rates of bivalves. Nevertheless, in many coastal areas high pCO2 variability is encountered already today. Kiel Fjord (Western Baltic Sea) is a brackish (12-20 g kg(-1) ) and CO2 enriched habitat, but the blue mussel Mytilus edulis dominates the benthic community. In a coupled field and laboratory study we examined the annual pCO2 variability in this habitat and the combined effects of elevated pCO2 and food availability on juvenile M. edulis growth and calcification. In the laboratory experiment, mussel growth and calcification were found to chiefly depend on food supply, with only minor impacts of pCO2 up to 3350 μatm. Kiel Fjord was characterized by strong seasonal pCO2 variability. During summer, maximal pCO2 values of 2500 μatm were observed at the surface and >3000 μatm at the bottom. However, the field growth experiment revealed seven times higher growth and calcification rates of M. edulis at a high pCO2 inner fjord field station (mean pCO2 ca. 1000 μatm) in comparison to a low pCO2 outer fjord station (ca. 600 μatm). In addition, mussels were able to out-compete the barnacle Amphibalanus improvisus at the high pCO2 site. High mussel productivity at the inner fjord site was enabled by higher particulate organic carbon concentrations. Kiel Fjord is highly impacted by eutrophication, which causes bottom water hypoxia and consequently high seawater pCO2 . At the same time, elevated nutrient concentrations increase the energy availability for filter feeding organisms such as mussels. Thus, M. edulis can dominate over a seemingly more acidification resistant species such as A. improvisus. We conclude that benthic stages of M. edulis tolerate high ambient pCO2 when food supply is abundant and that important habitat characteristics such as species interactions and energy availability need to be considered to predict species vulnerability to ocean acidification.
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Affiliation(s)
- Jörn Thomsen
- GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany.
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20
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Stumpp M, Hu MY, Melzner F, Gutowska MA, Dorey N, Himmerkus N, Holtmann WC, Dupont ST, Thorndyke MC, Bleich M. Acidified seawater impacts sea urchin larvae pH regulatory systems relevant for calcification. Proc Natl Acad Sci U S A 2012; 109:18192-7. [PMID: 23077257 PMCID: PMC3497771 DOI: 10.1073/pnas.1209174109] [Citation(s) in RCA: 141] [Impact Index Per Article: 11.8] [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] [Indexed: 11/18/2022] Open
Abstract
Calcifying echinoid larvae respond to changes in seawater carbonate chemistry with reduced growth and developmental delay. To date, no information exists on how ocean acidification acts on pH homeostasis in echinoderm larvae. Understanding acid-base regulatory capacities is important because intracellular formation and maintenance of the calcium carbonate skeleton is dependent on pH homeostasis. Using H(+)-selective microelectrodes and the pH-sensitive fluorescent dye BCECF, we conducted in vivo measurements of extracellular and intracellular pH (pH(e) and pH(i)) in echinoderm larvae. We exposed pluteus larvae to a range of seawater CO(2) conditions and demonstrated that the extracellular compartment surrounding the calcifying primary mesenchyme cells (PMCs) conforms to the surrounding seawater with respect to pH during exposure to elevated seawater pCO(2). Using FITC dextran conjugates, we demonstrate that sea urchin larvae have a leaky integument. PMCs and spicules are therefore directly exposed to strong changes in pH(e) whenever seawater pH changes. However, measurements of pH(i) demonstrated that PMCs are able to fully compensate an induced intracellular acidosis. This was highly dependent on Na(+) and HCO(3)(-), suggesting a bicarbonate buffer mechanism involving secondary active Na(+)-dependent membrane transport proteins. We suggest that, under ocean acidification, maintained pH(i) enables calcification to proceed despite decreased pH(e). However, this probably causes enhanced costs. Increased costs for calcification or cellular homeostasis can be one of the main factors leading to modifications in energy partitioning, which then impacts growth and, ultimately, results in increased mortality of echinoid larvae during the pelagic life stage.
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Affiliation(s)
- Meike Stumpp
- Institute of Physiology, Christian Albrechts University Kiel, 24098 Kiel, Germany
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany; and
- Department of Biological and Environmental Sciences, The Sven Lovén Centre for Marine Science, University of Gothenburg, Kristineberg, 45178 Fiskebäckskil, Sweden
| | - Marian Y. Hu
- Institute of Physiology, Christian Albrechts University Kiel, 24098 Kiel, Germany
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany; and
- Department of Biological and Environmental Sciences, The Sven Lovén Centre for Marine Science, University of Gothenburg, Kristineberg, 45178 Fiskebäckskil, Sweden
| | - Frank Melzner
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany; and
| | - Magdalena A. Gutowska
- Institute of Physiology, Christian Albrechts University Kiel, 24098 Kiel, Germany
- Helmholtz Centre for Ocean Research Kiel (GEOMAR), 24105 Kiel, Germany; and
| | - Narimane Dorey
- Department of Biological and Environmental Sciences, The Sven Lovén Centre for Marine Science, University of Gothenburg, Kristineberg, 45178 Fiskebäckskil, Sweden
| | - Nina Himmerkus
- Institute of Physiology, Christian Albrechts University Kiel, 24098 Kiel, Germany
| | - Wiebke C. Holtmann
- Institute of Physiology, Christian Albrechts University Kiel, 24098 Kiel, Germany
| | - Sam T. Dupont
- Department of Biological and Environmental Sciences, The Sven Lovén Centre for Marine Science, University of Gothenburg, Kristineberg, 45178 Fiskebäckskil, Sweden
| | - Michael C. Thorndyke
- Department of Biological and Environmental Sciences, The Sven Lovén Centre for Marine Science, University of Gothenburg, Kristineberg, 45178 Fiskebäckskil, Sweden
| | - Markus Bleich
- Institute of Physiology, Christian Albrechts University Kiel, 24098 Kiel, Germany
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Föppl H, Haerendel G, Haser L, Lüst R, Melzner F, Meyer B, Neuss H, Rabben HH, Rieger E, Stöcker J, Stoffregen W. Preliminary results of electric field measurements in the auroral zone. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja073i001p00021] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Strobel A, Hu MY, Gutowska MA, Lieb B, Lucassen M, Melzner F, Pörtner HO, Mark FC. Influence of Temperature, Hypercapnia, and Development on the Relative Expression of Different Hemocyanin Isoforms in the Common CuttlefishSepia officinalis. ACTA ACUST UNITED AC 2012; 317:511-23. [DOI: 10.1002/jez.1743] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 05/21/2012] [Accepted: 06/05/2012] [Indexed: 12/20/2022]
Affiliation(s)
- Anneli Strobel
- Integrative Ecophysiology; Alfred Wegener Institute for Polar and Marine Research; Bremerhaven; Germany
| | | | | | - Bernhard Lieb
- Institute of Zoology; Johannes Gutenberg University of Mainz; Mainz; Germany
| | - Magnus Lucassen
- Integrative Ecophysiology; Alfred Wegener Institute for Polar and Marine Research; Bremerhaven; Germany
| | - Frank Melzner
- Biological Oceanography; Helmholtz Centre for Ocean Research Kiel (GEOMAR); Kiel; Germany
| | - Hans O. Pörtner
- Integrative Ecophysiology; Alfred Wegener Institute for Polar and Marine Research; Bremerhaven; Germany
| | - Felix C. Mark
- Integrative Ecophysiology; Alfred Wegener Institute for Polar and Marine Research; Bremerhaven; Germany
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Stumpp M, Trübenbach K, Brennecke D, Hu MY, Melzner F. Resource allocation and extracellular acid-base status in the sea urchin Strongylocentrotus droebachiensis in response to CO₂ induced seawater acidification. Aquat Toxicol 2012; 110-111:194-207. [PMID: 22343465 DOI: 10.1016/j.aquatox.2011.12.020] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 12/14/2011] [Accepted: 12/27/2011] [Indexed: 05/31/2023]
Abstract
Anthropogenic CO(2) emission will lead to an increase in seawater pCO(2) of up to 80-100 Pa (800-1000 μatm) within this century and to an acidification of the oceans. Green sea urchins (Strongylocentrotus droebachiensis) occurring in Kattegat experience seasonal hypercapnic and hypoxic conditions already today. Thus, anthropogenic CO(2) emissions will add up to existing values and will lead to even higher pCO(2) values >200 Pa (>2000 μatm). To estimate the green sea urchins' potential to acclimate to acidified seawater, we calculated an energy budget and determined the extracellular acid base status of adult S. droebachiensis exposed to moderately (102-145 Pa, 1007-1431 μatm) and highly (284-385 Pa, 2800-3800 μatm) elevated seawater pCO(2) for 10 and 45 days. A 45-day exposure to elevated pCO(2) resulted in a shift in energy budgets, leading to reduced somatic and reproductive growth. Metabolic rates were not significantly affected, but ammonium excretion increased in response to elevated pCO(2). This led to decreased O:N ratios. These findings suggest that protein metabolism is possibly enhanced under elevated pCO(2) in order to support ion homeostasis by increasing net acid extrusion. The perivisceral coelomic fluid acid-base status revealed that S. droebachiensis is able to fully (intermediate pCO(2)) or partially (high pCO(2)) compensate extracellular pH (pH(e)) changes by accumulation of bicarbonate (maximum increases 2.5mM), albeit at a slower rate than typically observed in other taxa (10-day duration for full pH(e) compensation). At intermediate pCO(2), sea urchins were able to maintain fully compensated pH(e) for 45 days. Sea urchins from the higher pCO(2) treatment could be divided into two groups following medium-term acclimation: one group of experimental animals (29%) contained remnants of food in their digestive system and maintained partially compensated pH(e) (+2.3mM HCO(3)(-)), while the other group (71%) exhibited an empty digestive system and a severe metabolic acidosis (-0.5 pH units, -2.4mM HCO(3)(-)). There was no difference in mortality between the three pCO(2) treatments. The results of this study suggest that S. droebachiensis occurring in the Kattegat might be pre-adapted to hypercapnia due to natural variability in pCO(2) in its habitat. We show for the first time that some echinoderm species can actively compensate extracellular pH. Seawater pCO(2) values of >200 Pa, which will occur in the Kattegat within this century during seasonal hypoxic events, can possibly only be endured for a short time period of a few weeks. Increases in anthropogenic CO(2) emissions and leakages from potential sub-seabed CO(2) storage (CCS) sites thus impose a threat to the ecologically and economically important species S. droebachiensis.
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Affiliation(s)
- M Stumpp
- Biological Oceanography, Leibniz Institute of Marine Sciences (IFM-GEOMAR), Kiel, Germany.
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Tseng YC, Hu MY, Lin LY, Liu ST, Melzner F, Hwang PP. Convergence of acid‐base regulation in embryonic cephalopod and fish. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1070.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yung-Che Tseng
- Department of Life ScienceNational Taiwan Normal UniversityTaipei CityTaiwan
| | | | - Li-Yih Lin
- Department of Life ScienceNational Taiwan Normal UniversityTaipei CityTaiwan
| | - Sian-Tai Liu
- Department of Life ScienceNational Taiwan Normal UniversityTaipei CityTaiwan
| | - Frank Melzner
- Department of Biological OceanographyLeibniz-Institute of Marine Sciences (IFM-GEOMAR)KielGermany
| | - Pung-Pung Hwang
- Institute of Cellular and Organismic BiologyAcademia SinicaTaipei CityTaiwan
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Philipp EER, Kraemer L, Melzner F, Poustka AJ, Thieme S, Findeisen U, Schreiber S, Rosenstiel P. Massively parallel RNA sequencing identifies a complex immune gene repertoire in the lophotrochozoan Mytilus edulis. PLoS One 2012; 7:e33091. [PMID: 22448234 PMCID: PMC3308963 DOI: 10.1371/journal.pone.0033091] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 02/09/2012] [Indexed: 11/18/2022] Open
Abstract
The marine mussel Mytilus edulis and its closely related sister species are distributed world-wide and play an important role in coastal ecology and economy. The diversification in different species and their hybrids, broad ecological distribution, as well as the filter feeding mode of life has made this genus an attractive model to investigate physiological and molecular adaptations and responses to various biotic and abiotic environmental factors. In the present study we investigated the immune system of Mytilus, which may contribute to the ecological plasticity of this species. We generated a large Mytilus transcriptome database from different tissues of immune challenged and stress treated individuals from the Baltic Sea using 454 pyrosequencing. Phylogenetic comparison of orthologous groups of 23 species demonstrated the basal position of lophotrochozoans within protostomes. The investigation of immune related transcripts revealed a complex repertoire of innate recognition receptors and downstream pathway members including transcripts for 27 toll-like receptors and 524 C1q domain containing transcripts. NOD-like receptors on the other hand were absent. We also found evidence for sophisticated TNF, autophagy and apoptosis systems as well as for cytokines. Gill tissue and hemocytes showed highest expression of putative immune related contigs and are promising tissues for further functional studies. Our results partly contrast with findings of a less complex immune repertoire in ecdysozoan and other lophotrochozoan protostomes. We show that bivalves are interesting candidates to investigate the evolution of the immune system from basal metazoans to deuterostomes and protostomes and provide a basis for future molecular work directed to immune system functioning in Mytilus.
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Affiliation(s)
- Eva E R Philipp
- Institute of Clinical Molecular Biology, Christian-Albrechts-University Kiel, Kiel, Germany.
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Hu MY, Tseng YC, Lin LY, Chen PY, Charmantier-Daures M, Hwang PP, Melzner F. New insights into ion regulation of cephalopod molluscs: a role of epidermal ionocytes in acid-base regulation during embryogenesis. Am J Physiol Regul Integr Comp Physiol 2011; 301:R1700-9. [PMID: 21975645 DOI: 10.1152/ajpregu.00107.2011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The constraints of an active life in a pelagic habitat led to numerous convergent morphological and physiological adaptations that enable cephalopod molluscs and teleost fishes to compete for similar resources. Here, we show for the first time that such convergent developments are also found in the ontogenetic progression of ion regulatory tissues; as in teleost fish, epidermal ionocytes scattered on skin and yolk sac of cephalopod embryos appear to be responsible for ionic and acid-base regulation before gill epithelia become functional. Ion and acid-base regulation is crucial in cephalopod embryos, as they are surrounded by a hypercapnic egg fluid with a Pco(2) between 0.2 and 0.4 kPa. Epidermal ionocytes were characterized via immunohistochemistry, in situ hybridization, and vital dye-staining techniques. We found one group of cells that is recognized by concavalin A and MitoTracker, which also expresses Na(+)/H(+) exchangers (NHE3) and Na(+)-K(+)-ATPase. Similar to findings obtained in teleosts, these NHE3-rich cells take up sodium in exchange for protons, illustrating the energetic superiority of NHE-based proton excretion in marine systems. In vivo electrophysiological techniques demonstrated that acid equivalents are secreted by the yolk and skin integument. Intriguingly, epidermal ionocytes of cephalopod embryos are ciliated as demonstrated by scanning electron microscopy, suggesting a dual function of epithelial cells in water convection and ion regulation. These findings add significant knowledge to our mechanistic understanding of hypercapnia tolerance in marine organisms, as it demonstrates that marine taxa, which were identified as powerful acid-base regulators during hypercapnic challenges, already exhibit strong acid-base regulatory abilities during embryogenesis.
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Affiliation(s)
- Marian Y Hu
- Leibniz-Institute of Marine Sciences, Kiel, Germany
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Melzner F, Stange P, Trübenbach K, Thomsen J, Casties I, Panknin U, Gorb SN, Gutowska MA. Food supply and seawater pCO2 impact calcification and internal shell dissolution in the blue mussel Mytilus edulis. PLoS One 2011; 6:e24223. [PMID: 21949698 PMCID: PMC3174946 DOI: 10.1371/journal.pone.0024223] [Citation(s) in RCA: 153] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 08/08/2011] [Indexed: 12/03/2022] Open
Abstract
Progressive ocean acidification due to anthropogenic CO(2) emissions will alter marine ecosystem processes. Calcifying organisms might be particularly vulnerable to these alterations in the speciation of the marine carbonate system. While previous research efforts have mainly focused on external dissolution of shells in seawater under saturated with respect to calcium carbonate, the internal shell interface might be more vulnerable to acidification. In the case of the blue mussel Mytilus edulis, high body fluid pCO(2) causes low pH and low carbonate concentrations in the extrapallial fluid, which is in direct contact with the inner shell surface. In order to test whether elevated seawater pCO(2) impacts calcification and inner shell surface integrity we exposed Baltic M. edulis to four different seawater pCO(2) (39, 142, 240, 405 Pa) and two food algae (310-350 cells mL(-1) vs. 1600-2000 cells mL(-1)) concentrations for a period of seven weeks during winter (5°C). We found that low food algae concentrations and high pCO(2) values each significantly decreased shell length growth. Internal shell surface corrosion of nacreous ( = aragonite) layers was documented via stereomicroscopy and SEM at the two highest pCO(2) treatments in the high food group, while it was found in all treatments in the low food group. Both factors, food and pCO(2), significantly influenced the magnitude of inner shell surface dissolution. Our findings illustrate for the first time that integrity of inner shell surfaces is tightly coupled to the animals' energy budget under conditions of CO(2) stress. It is likely that under food limited conditions, energy is allocated to more vital processes (e.g. somatic mass maintenance) instead of shell conservation. It is evident from our results that mussels exert significant biological control over the structural integrity of their inner shell surfaces.
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Affiliation(s)
- Frank Melzner
- Biological Oceanography, Leibniz-Institute of Marine Sciences (IFM-GEOMAR), Kiel, Germany.
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Stumpp M, Wren J, Melzner F, Thorndyke MC, Dupont ST. CO2 induced seawater acidification impacts sea urchin larval development I: elevated metabolic rates decrease scope for growth and induce developmental delay. Comp Biochem Physiol A Mol Integr Physiol 2011; 160:331-40. [PMID: 21742050 DOI: 10.1016/j.cbpa.2011.06.022] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [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: 12/10/2010] [Revised: 06/20/2011] [Accepted: 06/21/2011] [Indexed: 11/19/2022]
Abstract
Anthropogenic CO(2) emissions are acidifying the world's oceans. A growing body of evidence is showing that ocean acidification impacts growth and developmental rates of marine invertebrates. Here we test the impact of elevated seawater pCO(2) (129 Pa, 1271 μatm) on early development, larval metabolic and feeding rates in a marine model organism, the sea urchin Strongylocentrotus purpuratus. Growth and development was assessed by measuring total body length, body rod length, postoral rod length and posterolateral rod length. Comparing these parameters between treatments suggests that larvae suffer from a developmental delay (by ca. 8%) rather than from the previously postulated reductions in size at comparable developmental stages. Further, we found maximum increases in respiration rates of +100% under elevated pCO(2), while body length corrected feeding rates did not differ between larvae from both treatments. Calculating scope for growth illustrates that larvae raised under high pCO(2) spent an average of 39 to 45% of the available energy for somatic growth, while control larvae could allocate between 78 and 80% of the available energy into growth processes. Our results highlight the importance of defining a standard frame of reference when comparing a given parameter between treatments, as observed differences can be easily due to comparison of different larval ages with their specific set of biological characters.
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Affiliation(s)
- M Stumpp
- Biological Oceanography, Leibniz Institute of Marine Sciences (IFM-GEOMAR), Kiel, Germany
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Hu MY, Tseng YC, Stumpp M, Gutowska MA, Kiko R, Lucassen M, Melzner F. Elevated seawater Pco2 differentially affects branchial acid-base transporters over the course of development in the cephalopod Sepia officinalis. Am J Physiol Regul Integr Comp Physiol 2011; 300:R1100-14. [DOI: 10.1152/ajpregu.00653.2010] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The specific transporters involved in maintenance of blood pH homeostasis in cephalopod molluscs have not been identified to date. Using in situ hybridization and immunohistochemical methods, we demonstrate that Na+/K+-ATPase ( soNKA), a V-type H+-ATPase ( soV-HA), and Na+/HCO3− cotransporter ( soNBC) are colocalized in NKA-rich cells in the gills of Sepia officinalis. mRNA expression patterns of these transporters and selected metabolic genes were examined in response to moderately elevated seawater Pco2 (0.16 and 0.35 kPa) over a time course of 6 wk in different ontogenetic stages. The applied CO2 concentrations are relevant for ocean acidification scenarios projected for the coming decades. We determined strong expression changes in late-stage embryos and hatchlings, with one to three log2-fold reductions in soNKA, soNBCe, socCAII, and COX. In contrast, no hypercapnia-induced changes in mRNA expression were observed in juveniles during both short- and long-term exposure. However, a transiently increased ion regulatory demand was evident during the initial acclimation reaction to elevated seawater Pco2. Gill Na+/K+-ATPase activity and protein concentration were increased by ∼15% during short (2–11 days) but not long-term (42-days) exposure. Our findings support the hypothesis that the energy budget of adult cephalopods is not significantly compromised during long-term exposure to moderate environmental hypercapnia. However, the downregulation of ion regulatory and metabolic genes in late-stage embryos, taken together with a significant reduction in somatic growth, indicates that cephalopod early life stages are challenged by elevated seawater Pco2.
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Affiliation(s)
- Marian Y. Hu
- Biological Oceanography, Leibniz-Institute of Marine Sciences (IFM-GEOMAR), Kiel, Germany
| | - Yung-Che Tseng
- Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China
| | - Meike Stumpp
- Biological Oceanography, Leibniz-Institute of Marine Sciences (IFM-GEOMAR), Kiel, Germany
| | | | - Rainer Kiko
- Biological Oceanography, Leibniz-Institute of Marine Sciences (IFM-GEOMAR), Kiel, Germany
| | - Magnus Lucassen
- Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany
| | - Frank Melzner
- Biological Oceanography, Leibniz-Institute of Marine Sciences (IFM-GEOMAR), Kiel, Germany
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Hu MY, Sucré E, Charmantier-Daures M, Charmantier G, Lucassen M, Himmerkus N, Melzner F. Localization of ion-regulatory epithelia in embryos and hatchlings of two cephalopods. Cell Tissue Res 2010; 339:571-83. [PMID: 20127256 DOI: 10.1007/s00441-009-0921-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Accepted: 12/16/2009] [Indexed: 10/19/2022]
Abstract
The tissue distribution and ontogeny of Na(+)/K(+)-ATPase has been examined as an indicator for ion-regulatory epithelia in whole animal sections of embryos and hatchlings of two cephalopod species: the squid Loligo vulgaris and the cuttlefish Sepia officinalis. This is the first report of the immunohistochemical localization of cephalopod Na(+)/K(+)-ATPase with the polyclonal antibody alpha (H-300) raised against the human alpha1-subunit of Na(+)/K(+)-ATPase. Na(+)/K(+)-ATPase immunoreactivity was observed in several tissues (gills, pancreatic appendages, nerves), exclusively located in baso-lateral membranes lining blood sinuses. Furthermore, large single cells in the gill of adult L. vulgaris specimens closely resembled Na(+)/K(+)-ATPase-rich cells described in fish. Immunohistochemical observations indicated that the amount and distribution of Na(+)/K(+)-ATPase in late cuttlefish embryos was similar to that found in juvenile and adult stages. The ion-regulatory epithelia (e.g., gills, excretory organs) of the squid embryos and paralarvae exhibited less differentiation than adults. Na(+)/K(+)-ATPase activities for whole animals were higher in hatchlings of S. officinalis (157.0 +/- 32.4 micromol g (FM) (-1) h(-1)) than in those of L. vulgaris (31.8 +/- 3.3 micromol g (FM) (-1) h(-1)). S. officinalis gills and pancreatic appendages achieved activities of 94.8 +/- 18.5 and 421.8 +/- 102.3 micromol(ATP) g (FM) (-1) h(-1), respectively. High concentrations of Na(+)/K(+)-ATPase in late cephalopod embryos might be important in coping with the challenging abiotic conditions (low pH, high pCO(2)) that these organisms encounter inside their eggs. Our results also suggest a higher sensitivity of squid vs. cuttlefish embryos to environmental acid-base disturbances.
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Affiliation(s)
- Marian Y Hu
- Leibniz Institute of Marine Sciences, Kiel, Germany.
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Gutowska MA, Melzner F, Langenbuch M, Bock C, Claireaux G, Pörtner HO. Acid–base regulatory ability of the cephalopod (Sepia officinalis) in response to environmental hypercapnia. J Comp Physiol B 2009; 180:323-35. [DOI: 10.1007/s00360-009-0412-y] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2009] [Revised: 09/18/2009] [Accepted: 09/28/2009] [Indexed: 10/20/2022]
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Thomsen J, Julia S, Agnes H, Melzner F. Impacts of hypercapnia and temperature on physiological performance of marine invertebrates from the Baltic Sea. Comp Biochem Physiol A Mol Integr Physiol 2009. [DOI: 10.1016/j.cbpa.2009.04.350] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Melzner F, Göbel S, Langenbuch M, Gutowska MA, Pörtner HO, Lucassen M. Swimming performance in Atlantic Cod (Gadus morhua) following long-term (4-12 months) acclimation to elevated seawater P(CO2). Aquat Toxicol 2009; 92:30-7. [PMID: 19223084 DOI: 10.1016/j.aquatox.2008.12.011] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Revised: 12/20/2008] [Accepted: 12/26/2008] [Indexed: 05/03/2023]
Abstract
Anthropogenic CO2 emissions lead to chronically elevated seawater CO2 partial pressures (hypercapnia). The induced ocean acidification will very likely be a relevant factor shaping future marine environments. CO2 exposure concomitantly challenges the animal's capacity of acid-base and ionic regulation as well as the ability to maintain energy metabolism and calcification. Under conditions of acute hypercapnia, numerous studies have revealed a broad range of tolerance levels displayed by various marine taxa. Thus, it is well known that, in contrast to many marine invertebrates, most teleost fish are able to fully compensate acid-base disturbances in short-term experiments (hours to several days). In order to determine whether marine fish are able to preserve aerobic scope following long-term incubation to elevated CO2, we exposed two groups of Atlantic Cod for 4 and 12 months to 0.3 and 0.6 kPa P(CO2), respectively. Measurements of standard and active metabolic rates, critical swimming speeds and aerobic scope of long-term incubated cod showed no deviations from control values, indicating that locomotory performance is not compromised by the different levels of chronic hypercapnia. While the maintenance of high activity levels is supported by a 2-fold increased Na+/K+-ATPase protein expression and 2-fold elevated Na+/K+-ATPase activity in the 12 month incubated fish (0.6 kPa P(CO2)), no such elevation in Na+/K+-ATPase activity could be observed in the group treated with 0.3 kPa P(CO2). Owing to the relevance of Na+/K+-ATPase as a general indicator for ion regulatory capacity, these results point at an adjustment of enzymatic activity to cope with the CO2 induced acid-base load at 0.6 kPa P(CO2) while under milder hypercapnic conditions the 'standard' Na+/K+-ATPase capacity might still be sufficient to maintain acid-base status.
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Affiliation(s)
- Frank Melzner
- IFM-GEOMAR Leibniz Institute of Marine Sciences, Biological Oceanography, Hohenbergstr 2, 24105 Kiel, Germany.
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Mark F, Melzner F, Bock C, Poertner H, Ellington C, Claireaux G. Thermal effects on cephalopod energy metabolism — A case study for Sepia officinalis. Comp Biochem Physiol A Mol Integr Physiol 2008. [DOI: 10.1016/j.cbpa.2008.04.452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Melzner F, Mark FC, Portner HO. Role of blood-oxygen transport in thermal tolerance of the cuttlefish, Sepia officinalis. Integr Comp Biol 2007; 47:645-55. [DOI: 10.1093/icb/icm074] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Gutowska M, Melzner F, Sartoris F, Pörtner H. Compensation of hypercapnia induced acid–base disturbance by Sepia officinalis (Cephalopoda). Comp Biochem Physiol A Mol Integr Physiol 2007. [DOI: 10.1016/j.cbpa.2007.01.403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Bremer K, Melzner F, Lucassen M, Pörtner H. Thermal acclimation of aerobic scope in a southern North Sea cod population. Comp Biochem Physiol A Mol Integr Physiol 2007. [DOI: 10.1016/j.cbpa.2007.01.463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Melzner F, Bock C, Pörtner H. Thermal sensitivity of the venous return system in the cephalopod Sepia officinalis. Comp Biochem Physiol A Mol Integr Physiol 2007. [DOI: 10.1016/j.cbpa.2007.01.343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Melzner F, Bock C, Pörtner HO. Allometry of thermal limitation in the cephalopod Sepia officinalis. Comp Biochem Physiol A Mol Integr Physiol 2007; 146:149-54. [PMID: 17234440 DOI: 10.1016/j.cbpa.2006.07.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [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: 01/05/2006] [Revised: 07/05/2006] [Accepted: 07/07/2006] [Indexed: 11/21/2022]
Abstract
Cuttlefish (Sepia officinalis) routine metabolic rate was determined in response to acute thermal changes at a rate of 1 degrees C h(-1) for a variety of animal sizes (15-496 g wet mass, laboratory reared at 15 degrees C). In a thermal frame of 11 to 23 degrees C, oxygen consumption rates (MO(2), in mumol O(2) g(-1) min(-1)) were observed to rise with increasing temperature (T, in degrees C) and to decline with increasing body mass (m, in g), according to the formula: ln MO(2)=-3.3+0.0945T-0.215 ln m (R(2)=0.93). Outside the above thermal window, animals were not able to increase MO(2) at similar rates, indicating a beginning oxygen limitation of metabolism. Large animals (>100 g body mass) already displayed lower than expected MO(2) values at 8 and 26 degrees C, while smaller animals (15 g wet mass) were characterized by a wider thermal window (MO(2) values deviated from expected rates at 5 and 29 degrees C). Morphometric data of cuttlefish mantle skin area was obtained to discuss size - related effects of skin respiration potential on thermal tolerance. Cuttlefish growth was observed to be isometric, as constant 'Vogel numbers' of 4.2 indicated (animal body masses: 11 to 401 g). In the same mass range, specific mantle surface area declined three-fold from 10.7 (0.24) (means+/-SD) to 3.3 (0.52) cm(2) g(-1). Thus, increased thermal tolerance in smaller animals may be enabled by a higher skin respiration potential due to higher specific skin surface areas. An elevated fraction of MO(2) provided by means of skin respiration in small animals could relieve the cardiovascular system, which previously has been found a major limiting component during acute thermal stress in cuttlefish.
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Affiliation(s)
- Frank Melzner
- Alfred Wegener Institute for Marine and Polar Research, Am Handelshafen 12, 27570 Bremerhaven, Germany.
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Melzner F, Bock C, Pörtner HO. Coordination between ventilatory pressure oscillations and venous return in the cephalopod Sepia officinalis under control conditions, spontaneous exercise and recovery. J Comp Physiol B 2006; 177:1-17. [PMID: 16868753 DOI: 10.1007/s00360-006-0104-9] [Citation(s) in RCA: 8] [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] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Revised: 06/09/2006] [Accepted: 06/16/2006] [Indexed: 10/24/2022]
Abstract
Venous blood flow was measured for the first time in a cephalopod. Blood velocity was determined in the anterior vena cava (AVC) of cuttlefish S. officinalis with a Doppler, while simultaneously, ventilatory pressure oscillations were recorded in the mantle cavity. In addition, magnetic resonance imaging (MRI) was employed to investigate pulsatile flow in other major vessels. Blood pulses in the AVC are obligatorily coupled to ventilatory pressure pulses, both in frequency and phase. AVC peak blood velocity (v(AVC)) in animals of 232 (+/- 30 SD) g wet mass at 15 degrees C was found to be 14.2 (+/- 7.1) cm s(-1), AVC stroke volume (SV(AVC)) was 0.2 (+/- 0.1) ml stroke(-1), AVC minute volume (MV(AVC)) amounted to 5.5 (+/- 2.8) ml min(-1). Intense exercise bouts of 1-2 min resulted in 2.2-fold increases in MV(AVC), enabled by 1.6-fold increments in both, AVC pulse frequency (f (AVC)) and v(AVC). As increases in blood flow occurred delayed in time by 1.7 min with regard to exercise periods, we concluded that it is not direct mantle cavity pressure conveyance that drives venous return in this cephalopod blood vessel. However, during jetting at high pressure amplitude (> 1 kPa), AVC blood flow and mantle cavity pressure pulse shapes completely overlap, suggesting that under these conditions, blood transport must be driven passively by mantle cavity pressure. MRI measurements at 15 degrees C also revealed that under resting conditions, f (AVC )and ventilation frequency (f (V)) match at 31.6 (+/- 2.1) strokes min(-1). In addition, rates of pulsations in the cephalic artery and in afferent branchial vessels did not significantly differ from f (AVC) and f (V). It is suggested that these adaptations are beneficial for high rates of oxygen extraction observed in S. officinalis and the energy conserving mode of life of the cuttlefish ecotype in general.
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Affiliation(s)
- Frank Melzner
- Alfred Wegener Institut for Marine and Polar Research, Am Handelshafen 12, Bremerhaven 27570, Germany.
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Melzner F, Bock C, Pörtner HO. Temperature-dependent oxygen extraction from the ventilatory current and the costs of ventilation in the cephalopod Sepia officinalis. J Comp Physiol B 2006; 176:607-21. [PMID: 16710699 DOI: 10.1007/s00360-006-0084-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [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: 01/16/2006] [Revised: 03/23/2006] [Accepted: 03/29/2006] [Indexed: 11/30/2022]
Abstract
Earlier work found cuttlefish (Sepia officinalis) ventilatory muscle tissue to progressively switch to an anaerobic mode of energy production at critical temperatures (T (c)) of 7.0 and 26.8 degrees C. These findings suggested that oxygen availability limits thermal tolerance. The present study was designed to elucidate whether it is the ventilatory apparatus that sets critical temperature thresholds during acute thermal stress. Routine metabolic rate (rmr) rose exponentially between 11 and 23 degrees C, while below (8 degrees C) and above (26 degrees C) this temperature range, rmr was significantly depressed. Ventilation frequency (f (V)) and mean mantle cavity pressure (MMP) followed an exponential relationship within the entire investigated temperature range (8-26 degrees C). Oxygen extraction from the ventilatory current (EO(2)) decreased in a sigmoidal fashion with temperature, falling from > 90% at 8 degrees C to 32% at 26 degrees C. Consequently, ventilatory minute volume (MV(V)) increased by a factor of 20 from 7 to 150% body weight min(-1) in the same temperature interval. Increases in MMP and MV(V) resulted in ventilatory muscle power output (P (out)) increasing by a factor of > 80 from 0.03 to 2.4 mW kg(-1) animal. Nonetheless, costs for ventilatory mechanics remain below 1.5% rmr in the natural thermal window of the population (English Channel, 9-17 degrees C), owing to very low MMPs of < 0.05 kPa driving the ventilatory stream, and may maximally rise to 8.6% rmr at 26 degrees C. Model calculations suggest that the ventilatory system can maintain high arterial PO(2) values of > 14 kPa over the entire temperature interval. We therefore conclude that the cuttlefish ventilation system is probably not limiting oxygen transfer during acute thermal stress. Depression of rmr, well before critical temperatures are being reached, is likely caused by circulatory capacity limitations and not by fatigue of ventilatory muscle fibres.
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Affiliation(s)
- Frank Melzner
- Alfred-Wegener-Institute for Marine and Polar Research, Am Handelshafen 12, 27570 Bremerhaven, Germany.
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Abstract
SUMMARYThe present study was designed to test the hypothesis of an oxygen limitation defining thermal tolerance in the European cuttlefish (Sepia officinalis). Mantle muscle organ metabolic status and pHiwere monitored using in vivo31P NMR spectroscopy, while mantle muscle performance was determined by recording mantle cavity pressure oscillations during ventilation and spontaneous exercise.Under control conditions (15°C), changes in muscle phospho-l-arginine (PLA) and inorganic phosphate (Pi)levels could be linearly related to frequently occurring, high-pressure mantle contractions with pressure amplitudes (MMPA) of >0.2 kPa. Accordingly,mainly MMPA of >2 kPa affected muscle PLA reserves, indicating that contractions with MMPA of <2 kPa only involve the thin layers of aerobic circular mantle musculature. On average, no more than 20% of muscle PLA was depleted during spontaneous exercise under control conditions.Subjecting animals to acute thermal change at an average rate of 1 deg. h–1 led to significant Pi accumulation (equivalent to PLA breakdown) and decrements in the free energy of ATP hydrolysis(dG/dζ) at both ends of the temperature window, starting at mean critical temperatures (Tc) of 7.0 and 26.8°C,respectively. Frequent groups of high-pressure mantle contractions could not(in the warm) or only partially (in the cold) be related to net PLA breakdown in mantle muscle, indicating an oxygen limitation of routine metabolism rather than exercise-related phosphagen use. We hypothesize that it is mainly the constantly working radial mantle muscles that become progressively devoid of oxygen. Estimates of very low dG/dζ values (–44 kJ mol–1) in this compartment, along with correlated stagnating ventilation pressures in the warm, support this hypothesis. In conclusion, we found evidence for an oxygen limitation of thermal tolerance in the cuttlefish Sepia officinalis, as indicated by a progressive transition of routine mantle metabolism to an anaerobic mode of energy production.
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Affiliation(s)
- Frank Melzner
- Alfred-Wegener-Institute for Marine and Polar Research, Am Handelshafen 12, 27570 Bremerhaven, Germany.
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Junginger H, Geiger G, Haerendel G, Melzner F, Amata E, Higel B. A statistical study of dayside magnetospheric electric field fluctuations with periods between 150 and 600 s. ACTA ACUST UNITED AC 1984. [DOI: 10.1029/ja089ia07p05495] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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