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Gusmão LC, Rodríguez E. Two sea anemones (Cnidaria: Anthozoa: Actiniaria) from the Southern Ocean with evidence of a deep-sea, polar lineage of burrowing sea anemones. Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlaa176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Hexacorals are important components of macrobenthic communities in the Southern Ocean, dominating Antarctic continental shelves. Most of the 119 sea anemones recorded for the Southern Ocean are endemic (81% and 25% endemic species and genera, respectively, one endemic family) with only two species extending beyond the limits of the Southern Ocean. Over 70% of the 83 genera in the Southern Ocean are monotypic, including half of the generic diversity in superfamily Actinostoloidea, which suggests that Antarctica has been isolated long enough for the evolution of new genera but not for many families to evolve. Here, we describe Chitinactis marmara gen. & sp. nov., a new monotypic actinostoloidean genus from Antarctica diagnosed by its unique bi-layered cuticle on column, hexamerous symmetry, unequal development of younger mesenteries and mesogleal tentacle musculature. We also re-describe and extend the geographic distribution of Scytophorus striatus, another endemic Antarctic species. Based on morphological and molecular data, we establish the phylogenetic position of C. marmara and discuss the implications of the phylogenetic position of S. striatus for the resurrection and circumscription of the family Halcampoididae and the evolution of burrowing sea anemones. Finally, we discuss evidence for an actinostoloidean deep-sea, polar lineage of burrowing sea anemones.
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Affiliation(s)
- Luciana C Gusmão
- Division of Invertebrate Zoology, American Museum of Natural History, New York, NY, USA
| | - Estefanía Rodríguez
- Division of Invertebrate Zoology, American Museum of Natural History, New York, NY, USA
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2
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Rowlands E, Galloway T, Manno C. A Polar outlook: Potential interactions of micro- and nano-plastic with other anthropogenic stressors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:142379. [PMID: 33254857 DOI: 10.1016/j.scitotenv.2020.142379] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/24/2020] [Accepted: 09/11/2020] [Indexed: 06/12/2023]
Abstract
Polar marine ecosystems may have higher sensitivity than other ecosystems to plastic pollution due to recurrent physical and biological features; presence of ice and high UV radiation, slow growth rates and weak genetic differentiation of resident biota, accumulation of persistent organic pollutants and heavy metals, and fast rates of warming and global ocean acidification. Here, we discuss potential sources of and exposure to micro- and nano-plastic in polar marine ecosystems and potential mixture effects of micro- and nano-plastic coupled with chemical and climate related stressors. We address the anthropogenic contaminants likely to be 'high risk' for interactions in Arctic and Antarctic waters for reasons such as accumulation under sea-ice, a known sink for plastic particulates. Consequently, we address the potential for localised plastic-chemical interactions and possible seasonal fluctuations in interactions associated with freeze-thaw events. The risks for keystone polar species are also considered, incorporating the behavioural and physiological traits of biota and addressing potential 'hotspot' areas. Finally, we discuss a possible direction for future research.
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Affiliation(s)
- Emily Rowlands
- British Antarctic Survey, High Cross, Madingley Rd, Cambridge CB3 0ET, United Kingdom of Great Britain and Northern Ireland; University of Exeter, College of Life and Environmental Science, Streatham Campus, Stocker Rd, Exeter EX4 4PY, United Kingdom of Great Britain and Northern Ireland.
| | - Tamara Galloway
- University of Exeter, College of Life and Environmental Science, Streatham Campus, Stocker Rd, Exeter EX4 4PY, United Kingdom of Great Britain and Northern Ireland
| | - Clara Manno
- British Antarctic Survey, High Cross, Madingley Rd, Cambridge CB3 0ET, United Kingdom of Great Britain and Northern Ireland
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Lauritano C, Roncalli V, Ambrosino L, Cieslak MC, Ianora A. First De Novo Transcriptome of the Copepod Rhincalanus gigas from Antarctic Waters. BIOLOGY 2020; 9:biology9110410. [PMID: 33266516 PMCID: PMC7700397 DOI: 10.3390/biology9110410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/16/2020] [Accepted: 11/19/2020] [Indexed: 01/23/2023]
Abstract
Simple Summary Compared to more accessible sites, organisms inhabiting Antarctic waters have been poorly investigated. This study provides the first molecular resource (transcriptome from whole individual) for the eucalanoid copepod Rhincalanus gigas, one of the predominant zooplankton species of Antarctic waters. Sequence analyses identified possible adaptation strategies adopted by the organism to cope with cold environments. Among those, we identified in R. gigas transcriptome three predicted genes encoding for antifreeze proteins and gene duplication within the glutathione metabolism pathway. This new molecular resource, provided here, will be useful to study the physiology, ecology, and biology of R. gigas and it increases the information available for polar environments. Abstract Antarctic waters are the largest almost untapped diversified resource of our planet. Molecular resources for Antarctic organisms are very limited and mostly represented by sequences used for species genotyping. In this study, we present the first transcriptome for the copepod Rhincalanus gigas, one of the predominant zooplankton species of Antarctic waters. This transcriptome represents also the first molecular resource for an eucalanoid copepod. The transcriptome is of high quality and completeness. The presence of three predicted genes encoding antifreeze proteins and gene duplication within the glutathione metabolism pathway are suggested as possible adaptations to cope with this harsh environment. The R. gigas transcriptome represents a powerful new resource for investigating the molecular basis associated with polar biological processes and ecology.
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Affiliation(s)
- Chiara Lauritano
- Marine Biotechnology Department, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy;
- Correspondence: ; Tel.: +39-081-5833-221
| | - Vittoria Roncalli
- Integrative Marine Ecology Department, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy;
| | - Luca Ambrosino
- Research Infrastructure for Marine Biological Resources Department, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy;
| | - Matthew C. Cieslak
- Pacific Biosciences Research Center, University of Hawai’i at Manoa, 1993 East-West Rd., Honolulu, HI 96822, USA;
| | - Adrianna Ianora
- Marine Biotechnology Department, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy;
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4
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Toward controlled breeding of the blackfin icefish Chaenocephalus aceratus (Lönnberg 1906): determination of spermatozoa concentration and evaluation of short- and long-term preservation of semen. Polar Biol 2020. [DOI: 10.1007/s00300-020-02729-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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5
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Giordano D, Pesce A, Vermeylen S, Abbruzzetti S, Nardini M, Marchesani F, Berghmans H, Seira C, Bruno S, Javier Luque F, di Prisco G, Ascenzi P, Dewilde S, Bolognesi M, Viappiani C, Verde C. Structural and functional properties of Antarctic fish cytoglobins-1: Cold-reactivity in multi-ligand reactions. Comput Struct Biotechnol J 2020; 18:2132-2144. [PMID: 32913582 PMCID: PMC7451756 DOI: 10.1016/j.csbj.2020.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 07/10/2020] [Accepted: 08/05/2020] [Indexed: 12/11/2022] Open
Abstract
While the functions of the recently discovered cytoglobin, ubiquitously expressed in vertebrate tissues, remain uncertain, Antarctic fish provide unparalleled models to study novel protein traits that may arise from cold adaptation. We report here the spectral, ligand-binding and enzymatic properties (peroxynitrite isomerization, nitrite-reductase activity) of cytoglobin-1 from two Antarctic fish, Chaenocephalus aceratus and Dissostichus mawsoni, and present the crystal structure of D. mawsoni cytoglobin-1. The Antarctic cytoglobins-1 display high O2 affinity, scarcely compatible with an O2-supply role, a slow rate constant for nitrite-reductase activity, and do not catalyze peroxynitrite isomerization. Compared with mesophilic orthologues, the cold-adapted cytoglobins favor binding of exogenous ligands to the hexa-coordinated bis-histidyl species, a trait related to their higher rate constant for distal-His/heme-Fe dissociation relative to human cytoglobin. At the light of a remarkable 3D-structure conservation, the observed differences in ligand-binding kinetics may reflect Antarctic fish cytoglobin-1 specific features in the dynamics of the heme distal region and of protein matrix cavities, suggesting adaptation to functional requirements posed by the cold environment. Taken together, the biochemical and biophysical data presented suggest that in Antarctic fish, as in humans, cytoglobin-1 unlikely plays a role in O2 transport, rather it may be involved in processes such as NO detoxification.
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Key Words
- C.aceCygb-1*, Mutant of C.aceCygb-1
- C.aceCygb-1, Cytoglobin-1 of C. aceratus
- CO, Carbon monoxide
- CYGB, Human Cygb
- Cold-adaptation
- Cygb, Cytoglobin
- Cygb-1, Cytoglobin 1
- Cygb-2, Cytoglobin 2
- Cygbh, Hexa-coordinated bis-histidyl species
- Cygbp, Penta-coordinated Cygb
- Cytoglobin
- D.mawCygb-1*, Mutant of D.mawCygb-1
- D.mawCygb-1, Cytoglobin-1 of D. mawsoni
- DTT, Dithiothreitol
- Hb, Hemoglobin
- Ligand properties
- MD, Molecular Dynamics
- Mb, Myoglobin
- NGB, Human neuroglobin
- NO dioxygenase
- NO, Nitric oxide
- RNS, Reactive Nitrogen Species
- ROS, Reactive Oxygen Species
- X-ray structure
- p50, O2 partial pressure required to achieve half saturation
- rms, Root-mean square
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Affiliation(s)
- Daniela Giordano
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111 80131 Napoli, Italy.,Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
| | - Alessandra Pesce
- Department of Physics, University of Genova, Via Dodecaneso 33, I-16121 Genova, Italy
| | - Stijn Vermeylen
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - Stefania Abbruzzetti
- Department of Mathematical, Physical and Computer Sciences, University of Parma, Parco Area delle Scienze 7A, 43124 Parma, Italy
| | - Marco Nardini
- Department of Biosciences, University of Milano, Via Celoria 26, I-20133 Milano, Italy
| | - Francesco Marchesani
- Department of Food and Drug, University of Parma, Parco Area delle Scienze 23A, 43124, Parma, Italy
| | - Herald Berghmans
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - Constantí Seira
- Department of Nutrition, Food Science and Gastronomy, Faculty of Pharmacy and Food Science, Institute of Biomedicine (IBUB) and Institute of Theoretical and Computational Chemistry (IQTCUB), University of Barcelona, Av. Prat de la Riba 171, Santa Coloma de Gramenet E-08921, Spain
| | - Stefano Bruno
- Department of Food and Drug, University of Parma, Parco Area delle Scienze 23A, 43124, Parma, Italy
| | - F Javier Luque
- Department of Nutrition, Food Science and Gastronomy, Faculty of Pharmacy and Food Science, Institute of Biomedicine (IBUB) and Institute of Theoretical and Computational Chemistry (IQTCUB), University of Barcelona, Av. Prat de la Riba 171, Santa Coloma de Gramenet E-08921, Spain
| | - Guido di Prisco
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111 80131 Napoli, Italy
| | - Paolo Ascenzi
- Interdepartmental Laboratory for Electron Microscopy, Roma Tre University, Via della Vasca Navale 79, I-00146 Roma, Italy
| | - Sylvia Dewilde
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - Martino Bolognesi
- Department of Biosciences, University of Milano, Via Celoria 26, I-20133 Milano, Italy
| | - Cristiano Viappiani
- Department of Mathematical, Physical and Computer Sciences, University of Parma, Parco Area delle Scienze 7A, 43124 Parma, Italy
| | - Cinzia Verde
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111 80131 Napoli, Italy.,Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
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Pallarés S, Colado R, Pérez‐Fernández T, Wesener T, Ribera I, Sánchez‐Fernández D. Heat tolerance and acclimation capacity in subterranean arthropods living under common and stable thermal conditions. Ecol Evol 2019; 9:13731-13739. [PMID: 31938477 PMCID: PMC6953556 DOI: 10.1002/ece3.5782] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 10/06/2019] [Accepted: 10/08/2019] [Indexed: 12/19/2022] Open
Abstract
Cave-dwelling ectotherms, which have evolved for millions of years under stable thermal conditions, could be expected to have adjusted their physiological limits to the narrow range of temperatures they experience and to be highly vulnerable to global warming. However, most of the few existing studies on thermal tolerance in subterranean invertebrates highlight that despite the fact that they show lower heat tolerance than most surface-dwelling species, their upper thermal limits are generally not adjusted to ambient temperature. The question remains to what extent this pattern is common across subterranean invertebrates. We studied basal heat tolerance and its plasticity in four species of distant arthropod groups (Coleoptera, Diplopoda, and Collembola) with different evolutionary histories but under similar selection pressures, as they have been exposed to the same constant environmental conditions for a long time. Adults were exposed at different temperatures for 1 week to determine upper lethal temperatures. Then, individuals from previous sublethal treatments were transferred to a higher temperature to determine acclimation capacity. Upper lethal temperatures of three of the studied species were similar to those reported for other subterranean species (between 20 and 25°C) and widely exceeded the cave temperature (13-14°C). The diplopod species showed the highest long-term heat tolerance detected so far for a troglobiont (i.e., obligate subterranean) species (median lethal temperature after 7 days exposure: 28°C) and a positive acclimation response. Our results agree with previous studies showing that heat tolerance in subterranean species is not determined by environmental conditions. Thus, subterranean species, even those living under similar climatic conditions, might be differently affected by global warming.
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Affiliation(s)
- Susana Pallarés
- Marine Biology and Ecology Research CentreSchool of Biological and Marine SciencesUniversity of PlymouthPlymouthUK
- Instituto de Ciencias AmbientalesUniversidad de Castilla‐La ManchaToledoSpain
| | - Raquel Colado
- Instituto de Ciencias AmbientalesUniversidad de Castilla‐La ManchaToledoSpain
- Departamento de Ecología e HidrologíaUniversidad de MurciaMurciaSpain
| | | | | | | | - David Sánchez‐Fernández
- Instituto de Ciencias AmbientalesUniversidad de Castilla‐La ManchaToledoSpain
- Departamento de Ecología e HidrologíaUniversidad de MurciaMurciaSpain
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Postlethwait JH, Yan YL, Desvignes T, Allard C, Titus T, Le François NR, Detrich HW. Embryogenesis and early skeletogenesis in the antarctic bullhead notothen, Notothenia coriiceps. Dev Dyn 2016; 245:1066-1080. [PMID: 27507212 DOI: 10.1002/dvdy.24437] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/01/2016] [Accepted: 07/04/2016] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Environmental temperature influences rates of embryonic development, but a detailed staging series for vertebrate embryos developing in the subzero cold of Antarctic waters is not yet available from fertilization to hatching. Given projected warming of the Southern Ocean, it is imperative to establish a baseline to evaluate potential effects of changing climate on fish developmental dynamics. RESULTS We studied the Bullhead notothen (Notothenia coriiceps), a notothenioid fish inhabiting waters between -1.9 and +2 °C. In vitro fertilization produced embryos that progressed through cleavage, epiboly, gastrulation, segmentation, organogenesis, and hatching. We compared morphogenesis spatially and temporally to Zebrafish and medaka. Experimental animals hatched after about 6 months to early larval stages. To help understand skeletogenesis, we analyzed late embryos for expression of sox9 and runx2, which regulate chondrogenesis, osteogenesis, and eye development. Results revealed that, despite their prolonged developmental time course, N. coriiceps embryos developed similarly to those of other teleosts with large yolk cells. CONCLUSIONS Our studies set the stage for future molecular analyses of development in these extremophile fish. Results provide a foundation for understanding the impact of ocean warming on embryonic development and larval recruitment of notothenioid fish, which are key factors in the marine trophic system. Developmental Dynamics 245:1066-1080, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | - Yi-Lin Yan
- Institute of Neuroscience, University of Oregon, Eugene, Oregon
| | | | - Corey Allard
- Biodôme de Montréal, Division des collections vivantes et recherche, Montréal, Quebec, Canada
| | - Tom Titus
- Institute of Neuroscience, University of Oregon, Eugene, Oregon
| | - Nathalie R Le François
- Department of Marine and Environmental Sciences, Marine Science Center, Northeastern University, Nahant, Massachusetts
| | - H William Detrich
- Biodôme de Montréal, Division des collections vivantes et recherche, Montréal, Quebec, Canada
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8
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Beers JM, Jayasundara N. Antarctic notothenioid fish: what are the future consequences of 'losses' and 'gains' acquired during long-term evolution at cold and stable temperatures? ACTA ACUST UNITED AC 2016; 218:1834-45. [PMID: 26085661 DOI: 10.1242/jeb.116129] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Antarctic notothenioids dominate the fish fauna of the Southern Ocean. Evolution for millions of years at cold and stable temperatures has led to the acquisition of numerous biochemical traits that allow these fishes to thrive in sub-zero waters. The gain of antifreeze glycoproteins has afforded notothenioids the ability to avert freezing and survive at temperatures often hovering near the freezing point of seawater. Additionally, possession of cold-adapted proteins and membranes permits them to sustain appropriate metabolic rates at exceptionally low body temperatures. The notothenioid genome is also distinguished by the disappearance of traits in some species, losses that might prove costly in a warmer environment. Perhaps the best-illustrated example is the lack of expression of hemoglobin in white-blooded icefishes from the family Channichthyidae. Loss of key elements of the cellular stress response, notably the heat shock response, has also been observed. Along with their attainment of cold tolerance, notothenioids have developed an extreme stenothermy and many species perish at temperatures only a few degrees above their habitat temperatures. Thus, in light of today's rapidly changing climate, it is critical to evaluate how these extreme stenotherms will respond to rising ocean temperatures. It is conceivable that the remarkable cold specialization of notothenioids may ultimately leave them vulnerable to future thermal increases and threaten their fitness and survival. Within this context, our review provides a current summary of the biochemical losses and gains that are known for notothenioids and examines these cold-adapted traits with a focus on processes underlying thermal tolerance and acclimation capacity.
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Affiliation(s)
- Jody M Beers
- Hopkins Marine Station, Stanford University, 120 Ocean View Boulevard, Pacific Grove, CA 93950, USA
| | - Nishad Jayasundara
- Nicholas School of the Environment, Duke University, 450 Research Drive, Durham, NC 27708, USA
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9
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Kašparová E, Van de Putte AP, Marshall C, Janko K. Lifestyle and Ice: The Relationship between Ecological Specialization and Response to Pleistocene Climate Change. PLoS One 2015; 10:e0138766. [PMID: 26535569 PMCID: PMC4636791 DOI: 10.1371/journal.pone.0138766] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 09/03/2015] [Indexed: 11/19/2022] Open
Abstract
Major climatic changes in the Pleistocene had significant effects on marine organisms and the environments in which they lived. The presence of divergent patterns of demographic history even among phylogenetically closely-related species sharing climatic changes raises questions as to the respective influence of species-specific traits on population structure. In this work we tested whether the lifestyle of Antarctic notothenioid benthic and pelagic fish species from the Southern Ocean influenced the concerted population response to Pleistocene climatic fluctuations. This was done by a comparative analysis of sequence variation at the cyt b and S7 loci in nine newly sequenced and four re-analysed species. We found that all species underwent more or less intensive changes in population size but we also found consistent differences between demographic histories of pelagic and benthic species. Contemporary pelagic populations are significantly more genetically diverse and bear traces of older demographic expansions than less diverse benthic species that show evidence of more recent population expansions. Our findings suggest that the lifestyles of different species have strong influences on their responses to the same environmental events. Our data, in conjunction with previous studies showing a constant diversification tempo of these species during the Pleistocene, support the hypothesis that Pleistocene glaciations had a smaller effect on pelagic species than on benthic species whose survival may have relied upon ephemeral refugia in shallow shelf waters. These findings suggest that the interaction between lifestyle and environmental changes should be considered in genetic analyses.
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Affiliation(s)
- Eva Kašparová
- Laboratory of Fish Genetics, Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburska 89, 27721 Libechov, Czech Republic
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Kvetna 8, 603 65, Brno, Czech Republic
- * E-mail: (EK); (KJ)
| | - Anton P. Van de Putte
- Laboratory of Biodiversity and Evolutionary Genomics, Katholieke Universiteit Leuven, Ch. Deberiotstraat 32, B-3000 Leuven, Belgium
| | - Craig Marshall
- Department of Biochemistry, and Genetics Otago, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - Karel Janko
- Laboratory of Fish Genetics, Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburska 89, 27721 Libechov, Czech Republic
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Kvetna 8, 603 65, Brno, Czech Republic
- Centre for Polar Ecology, University of South Bohemia in Ceské Budejovice, Na Zlate stoce 3, 370 05, Ceske Budejovice, Czech Republic
- Life Science Research Centre, Department of Biology and Ecology, Faculty of Natural Sciences, University of Ostrava, Chittussiho 10, 710 00 Silesian Ostrava, Czech Republic
- * E-mail: (EK); (KJ)
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Flynn EE, Bjelde BE, Miller NA, Todgham AE. Ocean acidification exerts negative effects during warming conditions in a developing Antarctic fish. CONSERVATION PHYSIOLOGY 2015; 3:cov033. [PMID: 27293718 PMCID: PMC4778439 DOI: 10.1093/conphys/cov033] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/16/2015] [Accepted: 06/18/2015] [Indexed: 05/30/2023]
Abstract
Anthropogenic CO2 is rapidly causing oceans to become warmer and more acidic, challenging marine ectotherms to respond to simultaneous changes in their environment. While recent work has highlighted that marine fishes, particularly during early development, can be vulnerable to ocean acidification, we lack an understanding of how life-history strategies, ecosystems and concurrent ocean warming interplay with interspecific susceptibility. To address the effects of multiple ocean changes on cold-adapted, slowly developing fishes, we investigated the interactive effects of elevated partial pressure of carbon dioxide (pCO2) and temperature on the embryonic physiology of an Antarctic dragonfish (Gymnodraco acuticeps), with protracted embryogenesis (∼10 months). Using an integrative, experimental approach, our research examined the impacts of near-future warming [-1 (ambient) and 2°C (+3°C)] and ocean acidification [420 (ambient), 650 (moderate) and 1000 μatm pCO2 (high)] on survival, development and metabolic processes over the course of 3 weeks in early development. In the presence of increased pCO2 alone, embryonic mortality did not increase, with greatest overall survival at the highest pCO2. Furthermore, embryos were significantly more likely to be at a later developmental stage at high pCO2 by 3 weeks relative to ambient pCO2. However, in combined warming and ocean acidification scenarios, dragonfish embryos experienced a dose-dependent, synergistic decrease in survival and developed more slowly. We also found significant interactions between temperature, pCO2 and time in aerobic enzyme activity (citrate synthase). Increased temperature alone increased whole-organism metabolic rate (O2 consumption) and developmental rate and slightly decreased osmolality at the cost of increased mortality. Our findings suggest that developing dragonfish are more sensitive to ocean warming and may experience negative physiological effects of ocean acidification only in the presence of an increased temperature. In addition to reduced hatching success, alterations in development and metabolism due to ocean warming and acidification could have negative ecological consequences owing to changes in phenology (i.e. early hatching) in the highly seasonal Antarctic ecosystem.
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Affiliation(s)
- Erin E Flynn
- Department of Biology, San Francisco State University, San Francisco, CA 94132, USA
- Department of Animal Sciences, University of California, Davis, CA 95616, USA
| | - Brittany E Bjelde
- Department of Animal Sciences, University of California, Davis, CA 95616, USA
| | - Nathan A Miller
- Department of Biology, San Francisco State University, San Francisco, CA 94132, USA
- Department of Animal Sciences, University of California, Davis, CA 95616, USA
| | - Anne E Todgham
- Department of Animal Sciences, University of California, Davis, CA 95616, USA
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Strobel A, Burkhardt-Holm P, Schmid P, Segner H. Benzo(a)pyrene Metabolism and EROD and GST Biotransformation Activity in the Liver of Red- and White-Blooded Antarctic Fish. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:8022-8032. [PMID: 25965896 DOI: 10.1021/acs.est.5b00176] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Climate change and anthropogenic pollution are of increasing concern in remote areas such as Antarctica. The evolutionary adaptation of Antarctic notothenioid fish to the cold and stable Southern Ocean led to a low plasticity of their physiological functions, what may limit their capacity to deal with altered temperature regimes and pollution in the Antarctic environment. Using a biochemical approach, we aimed to assess the hepatic biotransformation capacities of Antarctic fish species by determining (i) the activities of ethoxyresorufin-O-deethylase (EROD) and glutathione-S-transferase (GST), and (ii) the metabolic clearance of benzo(a)pyrene by hepatic S9 supernatants. In addition, we determined the thermal sensitivity of the xenobiotic biotransformation enzymes. We investigated the xenobiotic metabolism of the red-blooded Gobionotothen gibberifrons and Notothenia rossii, the hemoglobin-less Chaenocephalus aceratus and Champsocephalus gunnari, and the rainbow trout Oncorhynchus mykiss as a reference. Our results revealed similar metabolic enzyme activities and metabolic clearance rates between red- and white-blooded Antarctic fish, but significantly lower rates in comparison to rainbow trout. Therefore, bioaccumulation factors for metabolizable lipophilic contaminants may be higher in Antarctic than in temperate fish. Likewise, the thermal adaptive capacities and flexibilities of the EROD and GST activities in Antarctic fish were significantly lower than in rainbow trout. As a consequence, increasing water temperatures in the Southern Ocean will additionally compromise the already low detoxification capacities of Antarctic fish.
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Affiliation(s)
- Anneli Strobel
- †University of Basel, Departement of Environmental Sciences, Programme Man-Society-Environment MGU, Vesalgasse 1, CH-4051 Basel, Switzerland
- §University of Bern, Vetsuisse Faculty, Centre for Fish and Wildlife Health, Länggassstrasse 12, CH-3012 Bern, Switzerland
| | - Patricia Burkhardt-Holm
- †University of Basel, Departement of Environmental Sciences, Programme Man-Society-Environment MGU, Vesalgasse 1, CH-4051 Basel, Switzerland
- ∥Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2R3, Canada
| | - Peter Schmid
- ‡Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Helmut Segner
- §University of Bern, Vetsuisse Faculty, Centre for Fish and Wildlife Health, Länggassstrasse 12, CH-3012 Bern, Switzerland
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Young EF, Belchier M, Hauser L, Horsburgh GJ, Meredith MP, Murphy EJ, Pascoal S, Rock J, Tysklind N, Carvalho GR. Oceanography and life history predict contrasting genetic population structure in two Antarctic fish species. Evol Appl 2015; 8:486-509. [PMID: 26029262 PMCID: PMC4430772 DOI: 10.1111/eva.12259] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 02/27/2015] [Indexed: 01/27/2023] Open
Abstract
Understanding the key drivers of population connectivity in the marine environment is essential for the effective management of natural resources. Although several different approaches to evaluating connectivity have been used, they are rarely integrated quantitatively. Here, we use a 'seascape genetics' approach, by combining oceanographic modelling and microsatellite analyses, to understand the dominant influences on the population genetic structure of two Antarctic fishes with contrasting life histories, Champsocephalus gunnari and Notothenia rossii. The close accord between the model projections and empirical genetic structure demonstrated that passive dispersal during the planktonic early life stages is the dominant influence on patterns and extent of genetic structuring in both species. The shorter planktonic phase of C. gunnari restricts direct transport of larvae between distant populations, leading to stronger regional differentiation. By contrast, geographic distance did not affect differentiation in N. rossii, whose longer larval period promotes long-distance dispersal. Interannual variability in oceanographic flows strongly influenced the projected genetic structure, suggesting that shifts in circulation patterns due to climate change are likely to impact future genetic connectivity and opportunities for local adaptation, resilience and recovery from perturbations. Further development of realistic climate models is required to fully assess such potential impacts.
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Affiliation(s)
| | | | - Lorenz Hauser
- School of Aquatic and Fishery Sciences, University of Washington Seattle, WA, USA
| | - Gavin J Horsburgh
- NERC Biomolecular Analysis Facility, Department of Animal and Plant Sciences, University of Sheffield Sheffield, UK
| | | | | | - Sonia Pascoal
- School of Biological Sciences, Bangor University Bangor, Gwynedd, UK
| | - Jennifer Rock
- NERC Biomolecular Analysis Facility, Department of Animal and Plant Sciences, University of Sheffield Sheffield, UK ; School of Biological Sciences, Bangor University Bangor, Gwynedd, UK ; Present address: Department of Zoology, University of Otago Dunedin, 9054, New Zealand
| | - Niklas Tysklind
- School of Biological Sciences, Bangor University Bangor, Gwynedd, UK ; Present address: Campus Agronomique BP 709-97387, Kourou Cedex, France
| | - Gary R Carvalho
- School of Biological Sciences, Bangor University Bangor, Gwynedd, UK
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Christiansen JS, Mecklenburg CW, Karamushko OV. Arctic marine fishes and their fisheries in light of global change. GLOBAL CHANGE BIOLOGY 2014; 20:352-9. [PMID: 24105993 PMCID: PMC4255237 DOI: 10.1111/gcb.12395] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 09/02/2013] [Accepted: 09/05/2013] [Indexed: 05/21/2023]
Abstract
In light of ocean warming and loss of Arctic sea ice, harvested marine fishes of boreal origin (and their fisheries) move poleward into yet unexploited parts of the Arctic seas. Industrial fisheries, already in place on many Arctic shelves, will radically affect the local fish species as they turn up as unprecedented bycatch. Arctic marine fishes are indispensable to ecosystem structuring and functioning, but they are still beyond credible assessment due to lack of basic biological data. The time for conservation actions is now, and precautionary management practices by the Arctic coastal states are needed to mitigate the impact of industrial fisheries in Arctic waters. We outline four possible conservation actions: scientific credibility, 'green technology', legitimate management and overarching coordination.
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Affiliation(s)
- Jørgen S Christiansen
- Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, UiT - The Arctic University of Norway, Tromsø, NO-9037, Norway
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14
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15
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Nespolo RF, Bartheld JL, González A, Bruning A, Roff DA, Bacigalupe LD, Gaitán‐Espitia JD. The quantitative genetics of physiological and morphological traits in an invasive terrestrial snail: additive vs. non‐additive genetic variation. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12203] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Roberto F. Nespolo
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
| | - José L. Bartheld
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
| | - Avia González
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
| | - Andrea Bruning
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
| | - Derek A. Roff
- Department of Biology University of California Riverside CaliforniaUSA
| | - Leonardo D. Bacigalupe
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
| | - Juan D. Gaitán‐Espitia
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
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16
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Damerau M, Matschiner M, Salzburger W, Hanel R. Population divergences despite long pelagic larval stages: lessons from crocodile icefishes (Channichthyidae). Mol Ecol 2013; 23:284-99. [DOI: 10.1111/mec.12612] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 11/25/2013] [Accepted: 11/27/2013] [Indexed: 11/28/2022]
Affiliation(s)
- M. Damerau
- Thünen-Institute of Fisheries Ecology; Palmaille 9 22767 Hamburg Germany
| | - M. Matschiner
- Department of Mathematics and Statistics; Allan Wilson Centre of Molecular Ecology and Evolution; University of Canterbury; Private Bag 4800 Christchurch New Zealand
- Zoological Institute; University of Basel; Vesalgasse 1 4051 Basel Switzerland
| | - W. Salzburger
- Zoological Institute; University of Basel; Vesalgasse 1 4051 Basel Switzerland
| | - R. Hanel
- Thünen-Institute of Fisheries Ecology; Palmaille 9 22767 Hamburg Germany
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17
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Lecointre G, Améziane N, Boisselier MC, Bonillo C, Busson F, Causse R, Chenuil A, Couloux A, Coutanceau JP, Cruaud C, d'Acoz CD, De Ridder C, Denys G, Dettaï A, Duhamel G, Eléaume M, Féral JP, Gallut C, Havermans C, Held C, Hemery L, Lautrédou AC, Martin P, Ozouf-Costaz C, Pierrat B, Pruvost P, Puillandre N, Samadi S, Saucède T, Schubart C, David B. Is the species flock concept operational? The Antarctic shelf case. PLoS One 2013; 8:e68787. [PMID: 23936311 PMCID: PMC3732269 DOI: 10.1371/journal.pone.0068787] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 06/02/2013] [Indexed: 11/23/2022] Open
Abstract
There has been a significant body of literature on species flock definition but not so much about practical means to appraise them. We here apply the five criteria of Eastman and McCune for detecting species flocks in four taxonomic components of the benthic fauna of the Antarctic shelf: teleost fishes, crinoids (feather stars), echinoids (sea urchins) and crustacean arthropods. Practical limitations led us to prioritize the three historical criteria (endemicity, monophyly, species richness) over the two ecological ones (ecological diversity and habitat dominance). We propose a new protocol which includes an iterative fine-tuning of the monophyly and endemicity criteria in order to discover unsuspected flocks. As a result nine « full » species flocks (fulfilling the five criteria) are briefly described. Eight other flocks fit the three historical criteria but need to be further investigated from the ecological point of view (here called "core flocks"). The approach also shows that some candidate taxonomic components are no species flocks at all. The present study contradicts the paradigm that marine species flocks are rare. The hypothesis according to which the Antarctic shelf acts as a species flocks generator is supported, and the approach indicates paths for further ecological studies and may serve as a starting point to investigate the processes leading to flock-like patterning of biodiversity.
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Affiliation(s)
- Guillaume Lecointre
- UMR 7138 UPMC-MNHN-CNRS-IRD Systématique, Adaptation, Évolution, Département Systématique et Évolution, Muséum national d'Histoire naturelle, CP 39, Paris, France.
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Coppe A, Agostini C, Marino IAM, Zane L, Bargelloni L, Bortoluzzi S, Patarnello T. Genome evolution in the cold: Antarctic icefish muscle transcriptome reveals selective duplications increasing mitochondrial function. Genome Biol Evol 2013. [PMID: 23196969 PMCID: PMC3595028 DOI: 10.1093/gbe/evs108] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Antarctic notothenioids radiated over millions of years in subzero waters, evolving peculiar features, such as antifreeze glycoproteins and absence of heat shock response. Icefish, family Channichthyidae, also lack oxygen-binding proteins and display extreme modifications, including high mitochondrial densities in aerobic tissues. A genomic expansion accompanying the evolution of these fish was reported, but paucity of genomic information limits the understanding of notothenioid cold adaptation. We reconstructed and annotated the first skeletal muscle transcriptome of the icefish Chionodraco hamatus providing a new resource for icefish genomics (http://compgen.bio.unipd.it/chamatusbase/, last accessed December 12, 2012). We exploited deep sequencing of this energy-dependent tissue to test the hypothesis of selective duplication of genes involved in mitochondrial function. We developed a bioinformatic approach to univocally assign C. hamatus transcripts to orthology groups extracted from phylogenetic trees of five model species. Chionodraco hamatus duplicates were recorded for each orthology group allowing the identification of duplicated genes specific to the icefish lineage. Significantly more duplicates were found in the icefish when transcriptome data were compared with whole-genome data of model species. Indeed, duplicated genes were significantly enriched in proteins with mitochondrial localization, involved in mitochondrial function and biogenesis. In cold conditions and without oxygen-carrying proteins, energy production is challenging. The combination of high mitochondrial densities and the maintenance of duplicated genes involved in mitochondrial biogenesis and aerobic respiration might confer a selective advantage by improving oxygen diffusion and energy supply to aerobic tissues. Our results provide new insights into the genomic basis of icefish cold adaptation.
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Affiliation(s)
- Alessandro Coppe
- Department of Comparative Biomedicine and Food Science, University of Padova, Agripolis, Legnaro (Padova), Italy
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Van de Putte AP, Janko K, Kasparova E, Maes GE, Rock J, Koubbi P, Volckaert FA, Choleva L, Fraser KP, Smykla J, Van Houdt JK, Marshall C. Comparative phylogeography of three trematomid fishes reveals contrasting genetic structure patterns in benthic and pelagic species. Mar Genomics 2012. [DOI: 10.1016/j.margen.2012.05.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Verde C, Giordano D, di Prisco G, Andersen Ø. The haemoglobins of polar fish: evolutionary and physiological significance of multiplicity in Arctic fish. ACTA ACUST UNITED AC 2012. [DOI: 10.1080/14888386.2012.700345] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Hoffmann AA, Chown SL, Clusella-Trullas S. Upper thermal limits in terrestrial ectotherms: how constrained are they? Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.02036.x] [Citation(s) in RCA: 447] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Ary A. Hoffmann
- Departments of Zoology and Genetics; Bio21 Institute; The University of Melbourne; 30 Flemington Road; Parkville; Victoria; 3052; Australia
| | | | - Susana Clusella-Trullas
- Department of Botany and Zoology; Centre for Invasion Biology; Stellenbosch University; Private Bag X1; Matieland; 7602; South Africa
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Mark FC, Lucassen M, Strobel A, Barrera-Oro E, Koschnick N, Zane L, Patarnello T, Pörtner HO, Papetti C. Mitochondrial function in Antarctic nototheniids with ND6 translocation. PLoS One 2012; 7:e31860. [PMID: 22363756 PMCID: PMC3283701 DOI: 10.1371/journal.pone.0031860] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 01/13/2012] [Indexed: 12/02/2022] Open
Abstract
Fish of the suborder Notothenioidei have successfully radiated into the Southern Ocean and today comprise the dominant fish sub-order in Antarctic waters in terms of biomass and species abundance. During evolution in the cold and stable Antarctic climate, the Antarctic lineage of notothenioids developed several unique physiological adaptations, which make them extremely vulnerable to the rapid warming of Antarctic waters currently observed. Only recently, a further phenomenon exclusive to notothenioid fish was reported: the translocation of the mitochondrial gene encoding the NADH Dehydrogenase subunit 6 (ND6), an indispensable part of complex I in the mitochondrial electron transport system.This study investigated the potential physiological consequences of ND6 translocation for the function and thermal sensitivity of the electron transport system in isolated liver mitochondria of the two nototheniid species Notothenia coriiceps and Notothenia rossii, with special attention to the contributions of complex I (NADH DH) and complex II (Succinate DH) to oxidative phosphorylation. Furthermore, enzymatic activities of NADH:Cytochrome c Oxidoreductase and Cytochrome C Oxidase were measured in membrane-enriched tissue extracts.During acute thermal challenge (0-15°C), capacities of mitochondrial respiration and enzymatic function in the liver could only be increased until 9°C. Mitochondrial complex I (NADH Dehydrogenase) was fully functional but displayed a higher thermal sensitivity than the other complexes of the electron transport system, which may specifically result from its unique amino acid composition, revealing a lower degree of stability in notothenioids in general. We interpret the translocation of ND6 as functionally neutral but the change in amino acid sequence as adaptive and supportive of cold stenothermy in Antarctic nototheniids. From these findings, an enhanced sensitivity to ocean warming can be deduced for Antarctic notothenioid fish.
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Affiliation(s)
- Felix C Mark
- Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
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RUTSCHMANN SEREINA, MATSCHINER MICHAEL, DAMERAU MALTE, MUSCHICK MORITZ, LEHMANN MORITZF, HANEL REINHOLD, SALZBURGER WALTER. Parallel ecological diversification in Antarctic notothenioid fishes as evidence for adaptive radiation. Mol Ecol 2011; 20:4707-21. [DOI: 10.1111/j.1365-294x.2011.05279.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Bortolotto E, Bucklin A, Mezzavilla M, Zane L, Patarnello T. Gone with the currents: lack of genetic differentiation at the circum-continental scale in the Antarctic krill Euphausia superba. BMC Genet 2011; 12:32. [PMID: 21486439 PMCID: PMC3095564 DOI: 10.1186/1471-2156-12-32] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Accepted: 04/12/2011] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Southern Ocean fauna represent a significant amount of global biodiversity, whose origin may be linked to glacial cycles determining local extinction/eradication with ice advance, survival of refugee populations and post-glacial re-colonization. This pattern implies high potential for differentiation in benthic shelf species with limited dispersal, yet consequences for pelagic organisms are less clear. The present study investigates levels of genetic variation and population structure of the Antarctic krill Euphausia superba using mitochondrial DNA and EST-linked microsatellite markers for an unprecedentedly comprehensive sampling of its populations over a circum-Antarctic range. RESULTS MtDNA (ND1) sequences and EST-linked microsatellite markers indicated no clear sign of genetic structure among populations over large geographic scales, despite considerable power to detect differences inferred from forward-time simulations. Based on ND1, few instances of genetic heterogeneity, not significant after correction for multiple tests, were detected between geographic or temporal samples. Neutrality tests and mismatch distribution based on mtDNA sequences revealed strong evidence of past population expansion. Significant positive values of the parameter g (a measure of population growth) were obtained from microsatellite markers using a coalescent-based genealogical method and suggested a recent start (60,000 - 40,000 years ago) for the expansion. CONCLUSIONS The results provide evidence of lack of genetic heterogeneity of Antarctic krill at large geographic scales and unequivocal support for recent population expansion. Lack of genetic structuring likely reflects the tight link between krill and circum-Antarctic ocean currents and is consistent with the hypothesis that differentiation processes in Antarctic species are largely influenced by dispersal potential, whereas small-scale spatial and temporal differentiation might be due to local conditions leading to genetic patchiness. The signal of recent population growth suggests differential impact of glacial cycles on pelagic Antarctic species, which experienced population expansion during glaciations with increased available habitat, versus sedentary benthic shelf species. EST-linked microsatellites provide new perspectives to complement the results based on mtDNA and suggest that data-mining of EST libraries will be a useful approach to facilitate use of microsatellites for additional species.
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Affiliation(s)
- Erica Bortolotto
- Department of Biology, University of Padova, via U. Bassi 58B -35121 Padova, Italy
| | - Ann Bucklin
- Department of Marine Sciences, University of Connecticut, Groton CT 06340 USA
| | - Massimo Mezzavilla
- Department of Biology, University of Padova, via U. Bassi 58B -35121 Padova, Italy
| | - Lorenzo Zane
- Department of Biology, University of Padova, via U. Bassi 58B -35121 Padova, Italy
| | - Tomaso Patarnello
- Department of Public Health, Comparative Pathology and Veterinary Hygiene, University of Padova, Viale dell'Università 16, 35020 Legnaro (PD), Italy
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