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Ryder D, Stone D, Minardi D, Riley A, Avant J, Cross L, Soeffker M, Davidson D, Newman A, Thomson P, Darby C, van Aerle R. De novo assembly and annotation of the Patagonian toothfish (Dissostichus eleginoides) genome. BMC Genomics 2024; 25:233. [PMID: 38438840 PMCID: PMC10910785 DOI: 10.1186/s12864-024-10141-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 02/19/2024] [Indexed: 03/06/2024] Open
Abstract
BACKGROUND Patagonian toothfish (Dissostichus eleginoides) is an economically and ecologically important fish species in the family Nototheniidae. Juveniles occupy progressively deeper waters as they mature and grow, and adults have been caught as deep as 2500 m, living on or in just above the southern shelves and slopes around the sub-Antarctic islands of the Southern Ocean. As apex predators, they are a key part of the food web, feeding on a variety of prey, including krill, squid, and other fish. Despite its importance, genomic sequence data, which could be used for more accurate dating of the divergence between Patagonian and Antarctic toothfish, or establish whether it shares adaptations to temperature with fish living in more polar or equatorial climes, has so far been limited. RESULTS A high-quality D. eleginoides genome was generated using a combination of Illumina, PacBio and Omni-C sequencing technologies. To aid the genome annotation, the transcriptome derived from a variety of toothfish tissues was also generated using both short and long read sequencing methods. The final genome assembly was 797.8 Mb with a N50 scaffold length of 3.5 Mb. Approximately 31.7% of the genome consisted of repetitive elements. A total of 35,543 putative protein-coding regions were identified, of which 50% have been functionally annotated. Transcriptomics analysis showed that approximately 64% of the predicted genes (22,617 genes) were found to be expressed in the tissues sampled. Comparative genomics analysis revealed that the anti-freeze glycoprotein (AFGP) locus of D. eleginoides does not contain any AFGP proteins compared to the same locus in the Antarctic toothfish (Dissostichus mawsoni). This is in agreement with previously published results looking at hybridization signals and confirms that Patagonian toothfish do not possess AFGP coding sequences in their genome. CONCLUSIONS We have assembled and annotated the Patagonian toothfish genome, which will provide a valuable genetic resource for ecological and evolutionary studies on this and other closely related species.
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Affiliation(s)
- David Ryder
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK.
| | - David Stone
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK
| | - Diana Minardi
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK
| | - Ainsley Riley
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK
| | - Justin Avant
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK
| | - Lisa Cross
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK
| | - Marta Soeffker
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK
- Collaborative Centre for Sustainable Use of the Seas, University of East Anglia, Norwich, UK
| | | | | | | | - Chris Darby
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK
| | - Ronny van Aerle
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk, UK
- Centre for Sustainable Aquaculture Futures , University of Exeter, Exeter, UK
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Desvignes T, Bista I, Herrera K, Landes A, Postlethwait JH. Cold-Driven Hemoglobin Evolution in Antarctic Notothenioid Fishes Prior to Hemoglobin Gene Loss in White-Blooded Icefishes. Mol Biol Evol 2023; 40:msad236. [PMID: 37879119 PMCID: PMC10651078 DOI: 10.1093/molbev/msad236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 09/08/2023] [Accepted: 10/18/2023] [Indexed: 10/27/2023] Open
Abstract
Expression of multiple hemoglobin isoforms with differing physiochemical properties likely helps species adapt to different environmental and physiological conditions. Antarctic notothenioid fishes inhabit the icy Southern Ocean and display fewer hemoglobin isoforms, each with less affinity for oxygen than temperate relatives. Reduced hemoglobin multiplicity was proposed to result from relaxed selective pressure in the cold, thermally stable, and highly oxygenated Antarctic waters. These conditions also permitted the survival and diversification of white-blooded icefishes, the only vertebrates living without hemoglobin. To understand hemoglobin evolution during adaptation to freezing water, we analyzed hemoglobin genes from 36 notothenioid genome assemblies. Results showed that adaptation to frigid conditions shaped hemoglobin gene evolution by episodic diversifying selection concomitant with cold adaptation and by pervasive evolution in Antarctic notothenioids compared to temperate relatives, likely a continuing adaptation to Antarctic conditions. Analysis of hemoglobin gene expression in adult hematopoietic organs in various temperate and Antarctic species further revealed a switch in hemoglobin gene expression underlying hemoglobin multiplicity reduction in Antarctic fish, leading to a single hemoglobin isoform in adult plunderfishes and dragonfishes, the sister groups to icefishes. The predicted high hemoglobin multiplicity in Antarctic fish embryos based on transcriptomic data, however, raises questions about the molecular bases and physiological implications of diverse hemoglobin isoforms in embryos compared to adults. This analysis supports the hypothesis that the last common icefish ancestor was vulnerable to detrimental mutations affecting the single ancestral expressed alpha- and beta-globin gene pair, potentially predisposing their subsequent loss.
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Affiliation(s)
- Thomas Desvignes
- Institute of Neuroscience, University of Oregon, Eugene, OR 97403, USA
| | - Iliana Bista
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton CB10 1SA, United Kingdom
- LOEWE Centre for Translational Biodiversity Genomics, Frankfurt 60325, Germany
- Senckenberg Research Institute, Frankfurt 60325, Germany
| | - Karina Herrera
- Institute of Neuroscience, University of Oregon, Eugene, OR 97403, USA
| | - Audrey Landes
- Institute of Neuroscience, University of Oregon, Eugene, OR 97403, USA
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Bista I, Wood JMD, Desvignes T, McCarthy SA, Matschiner M, Ning Z, Tracey A, Torrance J, Sims Y, Chow W, Smith M, Oliver K, Haggerty L, Salzburger W, Postlethwait JH, Howe K, Clark MS, William Detrich H, Christina Cheng CH, Miska EA, Durbin R. Genomics of cold adaptations in the Antarctic notothenioid fish radiation. Nat Commun 2023; 14:3412. [PMID: 37296119 PMCID: PMC10256766 DOI: 10.1038/s41467-023-38567-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 05/05/2023] [Indexed: 06/12/2023] Open
Abstract
Numerous novel adaptations characterise the radiation of notothenioids, the dominant fish group in the freezing seas of the Southern Ocean. To improve understanding of the evolution of this iconic fish group, here we generate and analyse new genome assemblies for 24 species covering all major subgroups of the radiation, including five long-read assemblies. We present a new estimate for the onset of the radiation at 10.7 million years ago, based on a time-calibrated phylogeny derived from genome-wide sequence data. We identify a two-fold variation in genome size, driven by expansion of multiple transposable element families, and use the long-read data to reconstruct two evolutionarily important, highly repetitive gene family loci. First, we present the most complete reconstruction to date of the antifreeze glycoprotein gene family, whose emergence enabled survival in sub-zero temperatures, showing the expansion of the antifreeze gene locus from the ancestral to the derived state. Second, we trace the loss of haemoglobin genes in icefishes, the only vertebrates lacking functional haemoglobins, through complete reconstruction of the two haemoglobin gene clusters across notothenioid families. Both the haemoglobin and antifreeze genomic loci are characterised by multiple transposon expansions that may have driven the evolutionary history of these genes.
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Affiliation(s)
- Iliana Bista
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK.
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.
- Wellcome/CRUK Gurdon Institute, University of Cambridge, Tennis Court Rd, Cambridge, CB2 1QN, UK.
- Naturalis Biodiversity Center, Leiden, 2333 CR, the Netherlands.
| | - Jonathan M D Wood
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Thomas Desvignes
- University of Oregon, Institute of Neuroscience, 1254 University of Oregon, 13th Avenue, Eugene, OR, 97403, USA
| | - Shane A McCarthy
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK
| | - Michael Matschiner
- University of Oslo, Natural History Museum, University of Oslo, Sars' gate 1, 0562, Oslo, Norway
- University of Zurich, Department of Palaeontology and Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006, Zurich, Switzerland
| | - Zemin Ning
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Alan Tracey
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - James Torrance
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Ying Sims
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - William Chow
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Michelle Smith
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Karen Oliver
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Leanne Haggerty
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Walter Salzburger
- University of Basel, Zoological Institute, Department of Environmental Sciences, Vesalgasse 1, 4051, Basel, Switzerland
| | - John H Postlethwait
- University of Oregon, Institute of Neuroscience, 1254 University of Oregon, 13th Avenue, Eugene, OR, 97403, USA
| | - Kerstin Howe
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Melody S Clark
- British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - H William Detrich
- Northeastern University, Department of Marine and Environmental Sciences, Marine Science Centre, 430 Nahant Rd., Nahant, MA, 01908, USA
| | - C-H Christina Cheng
- Department of Evolution, Ecology, and Behaviour, University of Illinois, Urbana-Champaign, IL, 61801, USA
| | - Eric A Miska
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
- Wellcome/CRUK Gurdon Institute, University of Cambridge, Tennis Court Rd, Cambridge, CB2 1QN, UK
| | - Richard Durbin
- Wellcome Sanger Institute, Tree of Life, Wellcome Genome Campus, Hinxton, CB10 1SA, UK.
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.
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Molina AN, Pulgar JM, Rezende EL, Carter MJ. Heat tolerance of marine ectotherms in a warming Antarctica. GLOBAL CHANGE BIOLOGY 2023; 29:179-188. [PMID: 36045500 DOI: 10.1111/gcb.16402] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 08/11/2022] [Indexed: 06/15/2023]
Abstract
Global warming is affecting the Antarctic continent in complex ways. Because Antarctic organisms are specialized to living in the cold, they are vulnerable to increasing temperatures, although quantitative analyses of this issue are currently lacking. Here we compiled a total of 184 estimates of heat tolerance belonging to 39 marine species and quantified how survival is affected concomitantly by the intensity and duration of thermal stress. Species exhibit thermal limits displaced toward colder temperatures, with contrasting strategies between arthropods and fish that exhibit low tolerance to acute heat challenges, and brachiopods, echinoderms, and molluscs that tend to be more sensitive to chronic exposure. These differences might be associated with mobility. A dynamic mortality model suggests that Antarctic organisms already encounter temperatures that might be physiologically stressful and indicate that these ecological communities are indeed vulnerable to ongoing rising temperatures.
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Affiliation(s)
- Andrés N Molina
- Departamento de Ecología, Facultad de Ciencias Biológicas, Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - José M Pulgar
- Departamento de Ecología, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Enrico L Rezende
- Departamento de Ecología, Facultad de Ciencias Biológicas, Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mauricio J Carter
- Departamento de Ecología, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
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Morelli AM, Scholkmann F. The Significance of Lipids for the Absorption and Release of Oxygen in Biological Organisms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1438:93-99. [PMID: 37845446 DOI: 10.1007/978-3-031-42003-0_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
A critically important step for the uptake and transport of oxygen (O2) in living organisms is the crossing of the phase boundary between gas (or water) and lipid/proteins in the cell. Classically, this transport across the phase boundary is explained as a transport by proteins or protein-based structures. In our contribution here, we want to show the significance of passive transport of O2 also (and in some cases probably predominantly) through lipids in many if not all aerobic organisms. In plants, the significance of lipids for gas exchange (absorption of CO2 and release of O2) is well recognized. The leaves of plants have a cuticle layer as the last film on both sides formed by polyesters and lipids. In animals, the skin has sebum as its last layer consisting of a mixture of neutral fatty esters, cholesterol and waxes which are also at the border between the cells of the body and the air. The last cellular layers of skin are not vascularized therefore their metabolism totally depends on this extravasal O2 absorption, which cannot be replenished by the bloodstream. The human body absorbs about 0.5% of O2 through the skin. In the brain, myelin, surrounding nerve cell axons and being formed by oligodendrocytes, is most probably also responsible for enabling O2 transport from the extracellular space to the cells (neurons). Myelin, being not vascularized and consisting of water, lipids and proteins, seems to absorb O2 in order to transport it to the nerve cell axon as well as to perform extramitochondrial oxidative phosphorylation inside the myelin structure around the axons (i.e., myelin synthesizes ATP) - similarly to the metabolic process occurring in concentric multilamellar structures of cyanobacteria. Another example is the gas transport in the lung where lipids play a crucial role in the surfactant ensuring incorporation of O2 in the alveoli where there are lamellar body and tubular myelin which form multilayered surface films at the air-membrane border of the alveolus. According to our view, the role played by lipids in the physical absorption of gases appears to be crucial to the existence of many, if not all, of the living aerobic species.
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Affiliation(s)
| | - Felix Scholkmann
- Institute of Complementary and Integrative Medicine, University of Bern, Bern, Switzerland.
- Biomedical Optics Research Laboratory, Department of Neonatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
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6
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Giordano D, Verde C, Corti P. Nitric Oxide Production and Regulation in the Teleost Cardiovascular System. Antioxidants (Basel) 2022; 11:antiox11050957. [PMID: 35624821 PMCID: PMC9137985 DOI: 10.3390/antiox11050957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/06/2022] [Accepted: 05/09/2022] [Indexed: 01/08/2023] Open
Abstract
Nitric Oxide (NO) is a free radical with numerous critical signaling roles in vertebrate physiology. Similar to mammals, in the teleost system the generation of sufficient amounts of NO is critical for the physiological function of the cardiovascular system. At the same time, NO amounts are strictly controlled and kept within basal levels to protect cells from NO toxicity. Changes in oxygen tension highly influence NO bioavailability and can modulate the mechanisms involved in maintaining the NO balance. While NO production and signaling appears to have general similarities with mammalian systems, the wide range of environmental adaptations made by fish, particularly with regards to differing oxygen availabilities in aquatic habitats, creates a foundation for a variety of in vivo models characterized by different implications of NO production and signaling. In this review, we present the biology of NO in the teleost cardiovascular system and summarize the mechanisms of NO production and signaling with a special emphasis on the role of globin proteins in NO metabolism.
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Affiliation(s)
- Daniela Giordano
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino 111, 80131 Napoli, Italy; (D.G.); (C.V.)
- Department of Marine Biotechnology, Stazione Zoologica Anton Dohrn (SZN), Villa Comunale, 80121 Napoli, Italy
| | - Cinzia Verde
- Institute of Biosciences and BioResources (IBBR), National Research Council (CNR), Via Pietro Castellino 111, 80131 Napoli, Italy; (D.G.); (C.V.)
- Department of Marine Biotechnology, Stazione Zoologica Anton Dohrn (SZN), Villa Comunale, 80121 Napoli, Italy
| | - Paola Corti
- Heart, Lung, Blood, and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Division of Cardiology, Department of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Correspondence:
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Wuitchik SJ, Mogensen S, Barry TN, Paccard A, Jamniczky HA, Barrett RD, Rogers SM. Evolution of thermal physiology alters the projected range of threespine stickleback under climate change. Mol Ecol 2022; 31:2312-2326. [PMID: 35152483 DOI: 10.1111/mec.16396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/21/2022] [Accepted: 02/01/2022] [Indexed: 11/28/2022]
Abstract
Species distribution models (SDMs) are widely used to predict range shifts but could be unreliable under climate change scenarios because they do not account for evolution. The thermal physiology of a species is a key determinant of its range and thus incorporating thermal trait evolution into SDMs might be expected to alter projected ranges. We identified a genetic basis for physiological and behavioural traits that evolve in response to temperature change in natural populations of threespine stickleback (Gasterosteus aculeatus). Using these data, we created geographical range projections using a mechanistic niche area approach under two climate change scenarios. Under both scenarios, trait data were either static ("no evolution" models), allowed to evolve at observed evolutionary rates ("evolution" models) or allowed to evolve at a rate of evolution scaled by the trait variance that is explained by quantitative trait loci (QTL; "scaled evolution" models). We show that incorporating these traits and their evolution substantially altered the projected ranges for a widespread panmictic marine population, with over 7-fold increases in area under climate change projections when traits are allowed to evolve. Evolution-informed SDMs should improve the precision of forecasting range dynamics under climate change, and aid in their application to management and the protection of biodiversity.
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Affiliation(s)
- Sara J.S. Wuitchik
- Department of Biological Sciences University of Calgary 2500 University Dr NW Calgary AB T2N 1N4 Canada
- Informatics Group Harvard University 52 Oxford St Cambridge MA 02138 USA
- Department of Biology Boston University 5 Cummington Mall Boston MA 02215 USA
- Department of Biology University of Victoria 3800 Finnerty Rd Victoria BC V8P 5C2 Canada
- School of Environmental Science Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
| | - Stephanie Mogensen
- Department of Biological Sciences University of Calgary 2500 University Dr NW Calgary AB T2N 1N4 Canada
| | - Tegan N. Barry
- Department of Biological Sciences University of Calgary 2500 University Dr NW Calgary AB T2N 1N4 Canada
| | - Antoine Paccard
- Redpath Museum Department of Biology McGill University 845 Sherbrooke St W Montreal QC H3A 0G4 Canada
- McGill University Genome Center 740 Dr Penfield Avenue Montreal QC H3A 1A5 Canada
| | - Heather A. Jamniczky
- Department of Cell Biology & Anatomy Cumming School of Medicine University of Calgary 3330 Hospital Dr NW Calgary T2N 4N1 Canada
| | - Rowan D.H. Barrett
- Redpath Museum Department of Biology McGill University 845 Sherbrooke St W Montreal QC H3A 0G4 Canada
| | - Sean M. Rogers
- Department of Biological Sciences University of Calgary 2500 University Dr NW Calgary AB T2N 1N4 Canada
- Bamfield Marine Sciences Centre 100 Pachena Rd Bamfield BC V0R 1B0 Canada
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Majewski W, Holzmann M, Gooday AJ, Majda A, Mamos T, Pawlowski J. Cenozoic climatic changes drive evolution and dispersal of coastal benthic foraminifera in the Southern Ocean. Sci Rep 2021; 11:19869. [PMID: 34615927 PMCID: PMC8494791 DOI: 10.1038/s41598-021-99155-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 09/21/2021] [Indexed: 02/08/2023] Open
Abstract
The Antarctic coastal fauna is characterized by high endemism related to the progressive cooling of Antarctic waters and their isolation by the Antarctic Circumpolar Current. The origin of the Antarctic coastal fauna could involve either colonization from adjoining deep-sea areas or migration through the Drake Passage from sub-Antarctic areas. Here, we tested these hypotheses by comparing the morphology and genetics of benthic foraminifera collected from Antarctica, sub-Antarctic coastal settings in South Georgia, the Falkland Islands and Patagonian fjords. We analyzed four genera (Cassidulina, Globocassidulina, Cassidulinoides, Ehrenbergina) of the family Cassidulinidae that are represented by at least nine species in our samples. Focusing on the genera Globocassidulina and Cassidulinoides, our results showed that the first split between sub-Antarctic and Antarctic lineages took place during the mid-Miocene climate reorganization, probably about 20 to 17 million years ago (Ma). It was followed by a divergence between Antarctic species ~ 10 Ma, probably related to the cooling of deep water and vertical structuring of the water-column, as well as broadening and deepening of the continental shelf. The gene flow across the Drake Passage, as well as between South America and South Georgia, seems to have occurred from the Late Miocene to the Early Pliocene. It appears that climate warming during 7-5 Ma and the migration of the Polar Front breached biogeographic barriers and facilitated inter-species hybridization. The latest radiation coincided with glacial intensification (~ 2 Ma), which accelerated geographic fragmentation of populations, demographic changes, and genetic diversification in Antarctic species. Our results show that the evolution of Antarctic and sub-Antarctic coastal benthic foraminifera was linked to the tectonic and climatic history of the area, but their evolutionary response was not uniform and reflected species-specific ecological adaptations that influenced the dispersal patterns and biogeography of each species in different ways.
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Affiliation(s)
- Wojciech Majewski
- Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, 00-818, Warsaw, Poland.
| | - Maria Holzmann
- Department of Genetics and Evolution, University of Geneva, Sciences III, 30 Quai Ernest Ansermet, 1211, Geneve 4, Switzerland
| | - Andrew J Gooday
- National Oceanography Centre, European Way, Southampton, SO14 3ZH, UK
| | - Aneta Majda
- Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, 00-818, Warsaw, Poland
| | - Tomasz Mamos
- Department of Invertebrate Zoology and Hydrobiology, University of Lodz, Banacha 12/16, 90-237, Łódź, Poland
| | - Jan Pawlowski
- Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712, Sopot, Poland
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Gu S, Liu J, Xiong L, Dong J, Sun E, Hu H, Yang M, Nie L. Morphological mechanism allowing a parasitic leech, Ozobranchus jantseanus (Rhynchobdellida: Ozobranchidae), to survive in ultra-low temperatures. Biol Open 2021; 10:269137. [PMID: 34125176 PMCID: PMC8278134 DOI: 10.1242/bio.058524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 05/25/2021] [Indexed: 12/02/2022] Open
Abstract
Ozobranchus jantseanus is the largest metazoan known to survive in liquid nitrogen without pretreatment to date; however, the mechanism underlying this tolerance remains unclear. In this study, the first analyses of histological and morphological changes in normal, frozen, and dehydrated states were performed. Adults survived after direct placement in liquid nitrogen for 96 h, with a survival rate of approximately 86.7%. The leech could withstand rapid desiccation and its survival rate after rehydration was 100% when its water loss was below about 84.8%. After freezing, desiccation, and ethanol dehydration, the leech immediately formed a hemispherical shape. Particularly during drying, an obvious transparent glass-like substance was observed on surface. Scanning electron microscopy revealed many pores on the surface of the posterior sucker, creating a sponge-like structure, which may help to rapidly expel water, and a hemispherical shape may protect the internal organs by contraction and folding reconstruction in the anterior–posterior direction. A substantial amount of mucopolysaccharides on the surface and acid cells and collagen fibers in the body, all of which contained substantial polysaccharides, may play a key protective role during freezing. Our results indicate that the resistance of leeches to ultra-low temperatures can be explained by cryoprotective dehydration/vitrification strategies. This article has an associated First Person interview with the first author of the paper. Summary: The freeze tolerance mechanism of Ozobranchus jantseanus, the largest metazoan animal requiring no pretreatment that can survive in ultra-low temperature, was first studied from the perspective of morphology.
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Affiliation(s)
- Shengli Gu
- The Provincial Key Lab of the Conservation and Exploitation Research of Biological Resources in Anhui, Life Science College, Anhui Normal University, Wuhu, Anhui 241000, China.,Department of Parasitology, Wannan Medical College, Wuhu, Anhui 241002, China
| | - Jianjun Liu
- The Provincial Key Lab of the Conservation and Exploitation Research of Biological Resources in Anhui, Life Science College, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Lei Xiong
- The Provincial Key Lab of the Conservation and Exploitation Research of Biological Resources in Anhui, Life Science College, Anhui Normal University, Wuhu, Anhui 241000, China.,Department of Parasitology, Wannan Medical College, Wuhu, Anhui 241002, China
| | - Jinxiu Dong
- The Provincial Key Lab of the Conservation and Exploitation Research of Biological Resources in Anhui, Life Science College, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Entao Sun
- The Provincial Key Lab of the Conservation and Exploitation Research of Biological Resources in Anhui, Life Science College, Anhui Normal University, Wuhu, Anhui 241000, China.,Department of Parasitology, Wannan Medical College, Wuhu, Anhui 241002, China
| | - Haoran Hu
- Department of Parasitology, Wannan Medical College, Wuhu, Anhui 241002, China
| | - Mengli Yang
- The Provincial Key Lab of the Conservation and Exploitation Research of Biological Resources in Anhui, Life Science College, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Liuwang Nie
- The Provincial Key Lab of the Conservation and Exploitation Research of Biological Resources in Anhui, Life Science College, Anhui Normal University, Wuhu, Anhui 241000, China
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Thermal responses of two sub-Antarctic notothenioid fishes, the black southern cod Patagonotothen tessellata (Richardson, 1845) and the Magellan plunderfish Harpagifer bispinis (Forster, 1801), from southern South America. Polar Biol 2021. [DOI: 10.1007/s00300-021-02852-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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11
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Coggins BL, Pearson AC, Yampolsky LY. Does geographic variation in thermal tolerance in Daphnia represent trade-offs or conditional neutrality? J Therm Biol 2021; 98:102934. [PMID: 34016356 DOI: 10.1016/j.jtherbio.2021.102934] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 02/20/2021] [Accepted: 03/29/2021] [Indexed: 10/21/2022]
Abstract
Geographic variation in thermal tolerance in Daphnia seems to represent genetic load at the loci specifically responsible for heat tolerance resulting from conditional neutrality. We see no evidence of trade-offs between fitness-related traits at 25 °C vs. 10 °C or between two algal diets across Daphnia magna clones from a variety of locations representing the opposite ends of the distribution of long-term heat tolerance. Likewise, we found no evidence of within-environment trade-offs between heat tolerance and fitness-related traits in any of the environments. Neither short-term and long-term heat tolerance shows any consistent relationship with lipid fluorescence polarization and lipid peroxidation across clones or environments. Pervasive positive correlations between fitness-related traits indicate differences in genetic load rather than trade-off based local adaptation or thermal specialization. For heat tolerance such differences may be caused by either relaxation of stabilizing selection due to lower exposure to high temperature extremes, i.e., conditional neutrality, or by small effective population size followed by the recent range expansion.
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Affiliation(s)
- B L Coggins
- Department of Biological Sciences, East Tennessee State University, Johnson City TN, 37601, USA; Department of Biological Sciences, University of Notre Dame, IN, 46556, USA
| | - A C Pearson
- Department of Biological Sciences, East Tennessee State University, Johnson City TN, 37601, USA
| | - L Y Yampolsky
- Department of Biological Sciences, East Tennessee State University, Johnson City TN, 37601, USA; University of Basel, Department of Environmental Sciences, Zoology, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland.
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12
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Giordano D, Corti P, Coppola D, Altomonte G, Xue J, Russo R, di Prisco G, Verde C. Regulation of globin expression in Antarctic fish under thermal and hypoxic stress. Mar Genomics 2020; 57:100831. [PMID: 33250437 DOI: 10.1016/j.margen.2020.100831] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/18/2020] [Accepted: 11/18/2020] [Indexed: 01/27/2023]
Abstract
In the freezing waters of the Southern Ocean, Antarctic teleost fish, the Notothenioidei, have developed unique adaptations to cope with cold, including, at the extreme, the loss of hemoglobin in icefish. As a consequence, icefish are thought to be the most vulnerable of the Antarctic fish species to ongoing ocean warming. Some icefish also fail to express myoglobin but all appear to retain neuroglobin, cytoglobin-1, cytoglobin-2, and globin-X. Despite the lack of the inducible heat shock response, Antarctic notothenioid fish are endowed with physiological plasticity to partially compensate for environmental changes, as shown by numerous physiological and genomic/transcriptomic studies over the last decade. However, the regulatory mechanisms that determine temperature/oxygen-induced changes in gene expression remain largely unexplored in these species. Proteins such as globins are susceptible to environmental changes in oxygen levels and temperature, thus playing important roles in mediating Antarctic fish adaptations. In this study, we sequenced the full-length transcripts of myoglobin, neuroglobin, cytoglobin-1, cytoglobin-2, and globin-X from the Antarctic red-blooded notothenioid Trematomus bernacchii and the white-blooded icefish Chionodraco hamatus and evaluated transcripts levels after exposure to high temperature and low oxygen levels. Basal levels of globins are similar in the two species and both stressors affect the expression of Antarctic fish globins in brain, retina and gills. Temperature up-regulates globin expression more effectively in white-blooded than in red-blooded fish while hypoxia strongly up-regulates globins in red-blooded fish, particularly in the gills. These results suggest globins function as regulators of temperature and hypoxia tolerance. This study provides the first insights into globin transcriptional changes in Antarctic fish.
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Affiliation(s)
- Daniela Giordano
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, Napoli 80131, Italy; Department of Marine Biotechnology, Stazione Zoologica Anton Dohrn (SZN), Villa Comunale, Napoli 80121, Italy.
| | - Paola Corti
- Heart, Lung, Blood, and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA; Division of Cardiology, Department of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Daniela Coppola
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, Napoli 80131, Italy; Department of Marine Biotechnology, Stazione Zoologica Anton Dohrn (SZN), Villa Comunale, Napoli 80121, Italy
| | - Giovanna Altomonte
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, Napoli 80131, Italy; Department of Science, Roma Tre University, Viale Guglielmo Marconi 446, Roma I-00146, Italy
| | - Jianmin Xue
- Heart, Lung, Blood, and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Roberta Russo
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, Napoli 80131, Italy
| | - Guido di Prisco
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, Napoli 80131, Italy
| | - Cinzia Verde
- Institute of Biosciences and BioResources (IBBR), CNR, Via Pietro Castellino 111, Napoli 80131, Italy; Department of Marine Biotechnology, Stazione Zoologica Anton Dohrn (SZN), Villa Comunale, Napoli 80121, Italy
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13
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Fabri-Ruiz S, Navarro N, Laffont R, Danis B, Saucède T. Diversity of Antarctic Echinoids and Ecoregions of the Southern Ocean. BIOL BULL+ 2020. [DOI: 10.1134/s1062359020060047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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14
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Todgham AE, Mandic M. Understanding the Metabolic Capacity of Antarctic Fishes to Acclimate to Future Ocean Conditions. Integr Comp Biol 2020; 60:1425-1437. [PMID: 32814956 DOI: 10.1093/icb/icaa121] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Antarctic fishes have evolved under stable, extreme cold temperatures for millions of years. Adapted to thrive in the cold environment, their specialized phenotypes will likely render them particularly susceptible to future ocean warming and acidification as a result of climate change. Moving from a period of stability to one of environmental change, species persistence will depend on maintaining energetic equilibrium, or sustaining the increased energy demand without compromising important biological functions such as growth and reproduction. Metabolic capacity to acclimate, marked by a return to metabolic equilibrium through physiological compensation of routine metabolic rate (RMR), will likely determine which species will be better poised to cope with shifts in environmental conditions. Focusing on the suborder Notothenioidei, a dominant group of Antarctic fishes, and in particular four well-studied species, Trematomus bernacchii, Pagothenia borchgrevinki, Notothenia rossii, and N. coriiceps, we discuss metabolic acclimation potential to warming and CO2-acidification using an integrative and comparative framework. There are species-specific differences in the physiological compensation of RMR during warming and the duration of acclimation time required to achieve compensation; for some species, RMR fully recovered within 3.5 weeks of exposure, such as P. borchgrevinki, while for other species, such as N. coriiceps, RMR remained significantly elevated past 9 weeks of exposure. In all instances, added exposure to increased PCO2, further compromised the ability of species to return RMR to pre-exposure levels. The period of metabolic imbalance, marked by elevated RMR, was underlined by energetic disturbance and elevated energetic costs, which shifted energy away from fitness-related functions, such as growth. In T. bernacchii and N. coriiceps, long duration of elevated RMR impacted condition factor and/or growth rate. Low growth rate can affect development and ultimately the timing of reproduction, severely compromising the species' survival potential and the biodiversity of the notothenioid lineage. Therefore, the ability to achieve full compensation of RMR, and in a short-time frame, in order to avoid long term consequences of metabolic imbalance, will likely be an important determinant in a species' capacity to persist in a changing environment. Much work is still required to develop our understanding of the bioenergetics of Antarctic fishes in the face of environmental change, and a targeted approach of nesting a mechanistic focus in an ecological and comparative framework will better aid our predictions on the effect of global climate change on species persistence in the polar regions.
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Affiliation(s)
- Anne E Todgham
- Department of Animal Science, University of California Davis, Davis, CA 95616, USA
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15
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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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16
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Fabri-Ruiz S, Danis B, Navarro N, Koubbi P, Laffont R, Saucède T. Benthic ecoregionalization based on echinoid fauna of the Southern Ocean supports current proposals of Antarctic Marine Protected Areas under IPCC scenarios of climate change. GLOBAL CHANGE BIOLOGY 2020; 26:2161-2180. [PMID: 31919925 DOI: 10.1111/gcb.14988] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/20/2019] [Accepted: 12/27/2019] [Indexed: 06/10/2023]
Abstract
The Southern Ocean (SO) is among the regions on Earth that are undergoing regionally the fastest environmental changes. The unique ecological features of its marine life make it particularly vulnerable to the multiple effects of climate change. A network of Marine Protected Areas (MPAs) has started to be implemented in the SO to protect marine ecosystems. However, considering future predictions of the Intergovernmental Panel on Climate Change (IPCC), the relevance of current, static, MPAs may be questioned under future scenarios. In this context, the ecoregionalization approach can prove promising in identifying well-delimited regions of common species composition and environmental settings. These so-called ecoregions are expected to show similar biotic responses to environmental changes and can be used to define priority areas for the designation of new MPAs and the update of their current delimitation. In the present work, a benthic ecoregionalization of the entire SO is proposed for the first time based on abiotic environmental parameters and the distribution of echinoid fauna, a diversified and common member of Antarctic benthic ecosystems. A novel two-step approach was developed combining species distribution modeling with Random Forest and Gaussian Mixture modeling from species probabilities to define current ecoregions and predict future ecoregions under IPCC scenarios RCP 4.5 and 8.5. The ecological representativity of current and proposed MPAs of the SO is discussed with regard to the modeled benthic ecoregions. In all, 12 benthic ecoregions were determined under present conditions, they are representative of major biogeographic patterns already described. Our results show that the most dramatic changes can be expected along the Antarctic Peninsula, in East Antarctica and the sub-Antarctic islands under both IPCC scenarios. Our results advocate for a dynamic definition of MPAs, they also argue for improving the representativity of Antarctic ecoregions in proposed MPAs and support current proposals of Conservation of Antarctic Marine Living Resources for the creation of Antarctic MPAs.
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Affiliation(s)
- Salomé Fabri-Ruiz
- Biogéosciences, UMR CNRS/EPHE 6282, Université Bourgogne Franche-Comté, Dijon, France
- Laboratoire de Biologie Marine, Université Libre de Bruxelles, Brussels, Belgium
| | - Bruno Danis
- Laboratoire de Biologie Marine, Université Libre de Bruxelles, Brussels, Belgium
| | - Nicolas Navarro
- Biogéosciences, UMR CNRS/EPHE 6282, Université Bourgogne Franche-Comté, Dijon, France
- EPHE, PSL University, Paris, France
| | - Philippe Koubbi
- UFR 918 Terre Environnement et Biodiversité, Sorbonne Université, Paris Cedex 05, France
- IFREMER, Centre Manche mer du Nord. Laboratoire Halieutique de Manche-Mer du Nord, Boulogne-sur-Mer, France
| | - Rémi Laffont
- Biogéosciences, UMR CNRS/EPHE 6282, Université Bourgogne Franche-Comté, Dijon, France
| | - Thomas Saucède
- Biogéosciences, UMR CNRS/EPHE 6282, Université Bourgogne Franche-Comté, Dijon, France
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17
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Auvinet J, Graça P, Dettai A, Amores A, Postlethwait JH, Detrich HW, Ozouf-Costaz C, Coriton O, Higuet D. Multiple independent chromosomal fusions accompanied the radiation of the Antarctic teleost genus Trematomus (Notothenioidei:Nototheniidae). BMC Evol Biol 2020; 20:39. [PMID: 32192426 PMCID: PMC7082932 DOI: 10.1186/s12862-020-1600-3] [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: 08/13/2019] [Accepted: 03/03/2020] [Indexed: 12/20/2022] Open
Abstract
Background Chromosomal rearrangements are thought to be an important driving force underlying lineage diversification, but their link to speciation continues to be debated. Antarctic teleost fish of the family Nototheniidae (Notothenioidei) diversified in a changing environmental context, which led to ecological, morphological, and genetic differentiation among populations. In addition, extensive chromosomal repatterning accompanied species divergence in several clades. The most striking karyotypic changes involved the recent species radiation (about 10 My) of the genus Trematomus, with chromosomal pair numbers ranging between 29 and 12. These dramatic reductions in chromosome number resulted mostly from large-scale chromosome fusions. Multiple centric and/or tandem fusions have been hypothesized in at least seven of the twelve recognized Trematomus species. To reconstruct their evolutionary history, we employed comparative cytogenomics (BAC-FISH and chromosome painting) to reveal patterns of interspecific chromosomal orthologies across several notothenioid clades. Results We defined orthologous chromosomal segments of reference, termed Structural Units (SUs). SUs were identified in a total of 18 notothenioid species. We demonstrated for the first time that SUs were strongly conserved across every specimen examined, with chromosomal syntenies highlighting a paucity of intrachromosomal macro-rearrangements. Multiple independent fusions of these SUs were inferred in the Trematomus species, in contrast to the shared SU fusions in species of the sister lineage Notothenia. Conclusions The SU segments were defined units of chromosomal rearrangement in the entire family Nototheiidae, which diverged from the other notothenioid families 20 My ago. Some of the identified chromosomal syntenies within the SUs were even conserved in their closest relatives, the family Eleginopsidae. Comparing the timing of acquisition of the fusions in the closely related genera Notothenia and Trematomus of the nototheniid species family, we conclude that they exhibit distinct chromosomal evolutionary histories, which may be relevant to different speciation scenarios.
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Affiliation(s)
- Juliette Auvinet
- Sorbonne Université, CNRS, Université des Antilles, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005, Paris, France. .,Institut de Systématique, Evolution, Biodiversité (ISYEB) - Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 43, rue Cuvier, 75231, Paris Cedex 05, France. .,Department of Marine and Environmental Sciences, Marine Science Center, Northeastern University, Nahant, MA, 01908, USA.
| | - Paula Graça
- Sorbonne Université, CNRS, Université des Antilles, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005, Paris, France.,Institut de Systématique, Evolution, Biodiversité (ISYEB) - Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 43, rue Cuvier, 75231, Paris Cedex 05, France
| | - Agnès Dettai
- Institut de Systématique, Evolution, Biodiversité (ISYEB) - Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 43, rue Cuvier, 75231, Paris Cedex 05, France
| | - Angel Amores
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR, 97403, USA
| | - John H Postlethwait
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR, 97403, USA
| | - H William Detrich
- Department of Marine and Environmental Sciences, Marine Science Center, Northeastern University, Nahant, MA, 01908, USA
| | - Catherine Ozouf-Costaz
- Sorbonne Université, CNRS, Université des Antilles, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005, Paris, France
| | - Olivier Coriton
- Institut National de Recherche pour l'agriculture, l'alimentation et l'environnement, INRAE, UMR1349 IGEPP, Molecular cytogenetics Platform, BP35327, F-35653, Le Rheu Cedex, France
| | - Dominique Higuet
- Sorbonne Université, CNRS, Université des Antilles, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005, Paris, France. .,Institut de Systématique, Evolution, Biodiversité (ISYEB) - Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 43, rue Cuvier, 75231, Paris Cedex 05, France.
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18
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Corliss BA, Delalio LJ, Stevenson Keller TC, Keller AS, Keller DA, Corliss BH, Beers JM, Peirce SM, Isakson BE. Vascular Expression of Hemoglobin Alpha in Antarctic Icefish Supports Iron Limitation as Novel Evolutionary Driver. Front Physiol 2019; 10:1389. [PMID: 31780954 PMCID: PMC6861181 DOI: 10.3389/fphys.2019.01389] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 10/24/2019] [Indexed: 12/16/2022] Open
Abstract
Frigid temperatures of the Southern Ocean are known to be an evolutionary driver in Antarctic fish. For example, many fish have reduced red blood cell (RBC) concentration to minimize vascular resistance. Via the oxygen-carrying protein hemoglobin, RBCs contain the vast majority of the body's iron, which is known to be a limiting nutrient in marine ecosystems. Since lower RBC levels also lead to reduced iron requirements, we hypothesize that low iron availability was an additional evolutionary driver of Antarctic fish speciation. Antarctic Icefish of the family Channichthyidae are known to have an extreme alteration of iron metabolism due to loss of RBCs and two iron-binding proteins, hemoglobin and myoglobin. Loss of hemoglobin is considered a maladaptive trait allowed by relaxation of predator selection since extreme adaptations are required to compensate for the loss of oxygen-carrying capacity. However, iron dependency minimization may have driven hemoglobin loss instead of a random evolutionary event. Given the variety of functions that hemoglobin serves in the endothelium, we suspected the protein corresponding to the 3' truncated Hbα fragment (Hbα-3'f) that was not genetically excluded by icefish may still be expressed as a protein. Using whole mount confocal microscopy, we show that Hbα-3'f is expressed in the vascular endothelium of icefish retina, suggesting this Hbα fragment may still serve an important role in the endothelium. These observations support a novel hypothesis that iron minimization could have influenced icefish speciation with the loss of the iron-binding portion of Hbα in Hbα-3'f, as well as hemoglobin β and myoglobin.
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Affiliation(s)
- Bruce A Corliss
- Biomedical Engineering Department, University of Virginia, Charlottesville, VA, United States
| | - Leon J Delalio
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - T C Stevenson Keller
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Alexander S Keller
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States
| | | | - Bruce H Corliss
- Graduate School of Oceanography, University of Rhode Island, Kingston, RI, United States
| | - Jody M Beers
- Department of Biology, College of Charleston, Charleston, SC, United States
| | - Shayn M Peirce
- Biomedical Engineering Department, University of Virginia, Charlottesville, VA, United States
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, United States.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA, United States
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19
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Nikinmaa M, Berenbrink M, Brauner CJ. Regulation of erythrocyte function: Multiple evolutionary solutions for respiratory gas transport and its regulation in fish. Acta Physiol (Oxf) 2019; 227:e13299. [PMID: 31102432 DOI: 10.1111/apha.13299] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 05/03/2019] [Accepted: 05/13/2019] [Indexed: 01/01/2023]
Abstract
Gas transport concepts in vertebrates have naturally been formulated based on human blood. However, the first vertebrates were aquatic, and fish and tetrapods diverged hundreds of millions years ago. Water-breathing vertebrates live in an environment with low and variable O2 levels, making environmental O2 an important evolutionary selection pressure in fishes, and various features of their gas transport differ from humans. Erythrocyte function in fish is of current interest, because current environmental changes affect gas transport, and because especially zebrafish is used as a model in biomedical studies, making it important to understand the differences in gas transport between fish and mammals to be able to carry out meaningful studies. Of the close to thirty thousand fish species, teleosts are the most species-numerous group. However, two additional radiations are discussed: agnathans and elasmobranchs. The gas transport by elasmobranchs may be closest to the ancestors of tetrapods. The major difference in their haemoglobin (Hb) function to humans is their high urea tolerance. Agnathans differ from other vertebrates by having Hbs, where cooperativity is achieved by monomer-oligomer equilibria. Their erythrocytes also lack the anion exchange pathway with profound effects on CO2 transport. Teleosts are characterized by highly pH sensitive Hbs, which can fail to become fully O2 -saturated at low pH. An adrenergically stimulated Na+ /H+ exchanger has evolved in their erythrocyte membrane, and plasma-accessible carbonic anhydrase can be differentially distributed among their tissues. Together, and differing from other vertebrates, these features can maximize O2 unloading in muscle while ensuring O2 loading in gills.
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Affiliation(s)
| | - Michael Berenbrink
- Institute of Integrative Biology, Department of Evolution, Ecology and Behaviour University of Liverpool Liverpool UK
| | - Colin J. Brauner
- Department of Zoology University of British Columbia Vancouver British Columbia Canada
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20
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Kim BM, Ahn DH, Kang S, Jeong J, Jo E, Kim BK, Kim JH, Park H. Skin transcriptome profiling reveals the distinctive molecular effects of temperature changes on Antarctic bullhead notothen. Mol Cell Toxicol 2019. [DOI: 10.1007/s13273-019-0020-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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21
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Recent diversification in an ancient lineage of Notothenioid fishes (Bovichtus: Notothenioidei). Polar Biol 2019. [DOI: 10.1007/s00300-019-02489-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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22
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Kim BM, Amores A, Kang S, Ahn DH, Kim JH, Kim IC, Lee JH, Lee SG, Lee H, Lee J, Kim HW, Desvignes T, Batzel P, Sydes J, Titus T, Wilson CA, Catchen JM, Warren WC, Schartl M, Detrich HW, Postlethwait JH, Park H. Antarctic blackfin icefish genome reveals adaptations to extreme environments. Nat Ecol Evol 2019; 3:469-478. [PMID: 30804520 PMCID: PMC7307600 DOI: 10.1038/s41559-019-0812-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 01/15/2019] [Indexed: 11/09/2022]
Abstract
Icefishes (suborder Notothenioidei; family Channichthyidae) are the only vertebrates that lack functional haemoglobin genes and red blood cells. Here, we report a high-quality genome assembly and linkage map for the Antarctic blackfin icefish Chaenocephalus aceratus, highlighting evolved genomic features for its unique physiology. Phylogenomic analysis revealed that Antarctic fish of the teleost suborder Notothenioidei, including icefishes, diverged from the stickleback lineage about 77 million years ago and subsequently evolved cold-adapted phenotypes as the Southern Ocean cooled to sub-zero temperatures. Our results show that genes involved in protection from ice damage, including genes encoding antifreeze glycoprotein and zona pellucida proteins, are highly expanded in the icefish genome. Furthermore, genes that encode enzymes that help to control cellular redox state, including members of the sod3 and nqo1 gene families, are expanded, probably as evolutionary adaptations to the relatively high concentration of oxygen dissolved in cold Antarctic waters. In contrast, some crucial regulators of circadian homeostasis (cry and per genes) are absent from the icefish genome, suggesting compromised control of biological rhythms in the polar light environment. The availability of the icefish genome sequence will accelerate our understanding of adaptation to extreme Antarctic environments.
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Affiliation(s)
- Bo-Mi Kim
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea
| | - Angel Amores
- Institute of Neuroscience, University of Oregon, Eugene, OR, USA
| | - Seunghyun Kang
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea
| | - Do-Hwan Ahn
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea
| | - Jin-Hyoung Kim
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea
| | - Il-Chan Kim
- Department of Polar Life Science, Korea Polar Research Institute, Incheon, Korea
| | - Jun Hyuck Lee
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea.,Polar Science, University of Science and Technology, Daejeon, Korea
| | - Sung Gu Lee
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea.,Polar Science, University of Science and Technology, Daejeon, Korea
| | - Hyoungseok Lee
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea.,Polar Science, University of Science and Technology, Daejeon, Korea
| | - Jungeun Lee
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea.,Polar Science, University of Science and Technology, Daejeon, Korea
| | - Han-Woo Kim
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea.,Polar Science, University of Science and Technology, Daejeon, Korea
| | - Thomas Desvignes
- Institute of Neuroscience, University of Oregon, Eugene, OR, USA
| | - Peter Batzel
- Institute of Neuroscience, University of Oregon, Eugene, OR, USA
| | - Jason Sydes
- Institute of Neuroscience, University of Oregon, Eugene, OR, USA
| | - Tom Titus
- Institute of Neuroscience, University of Oregon, Eugene, OR, USA
| | | | - Julian M Catchen
- Department of Animal Biology, University of Illinois, Champaign, IL, USA
| | - Wesley C Warren
- McDonnell Genome Institute, Washington University, St. Louis, MO, USA
| | - Manfred Schartl
- Department of Developmental Biochemistry, Biocenter, University of Wuerzburg, Wuerzburg, Germany. .,Hagler Institute for Advanced Study, Texas A&M University, College Station, TX, USA. .,Department of Biology, Texas A&M University, College Station, TX, USA.
| | - H William Detrich
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA, USA.
| | | | - Hyun Park
- Unit of Polar Genomics, Korea Polar Research Institute, Incheon, Korea. .,Polar Science, University of Science and Technology, Daejeon, Korea.
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23
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Auvinet J, Graça P, Ghigliotti L, Pisano E, Dettaï A, Ozouf-Costaz C, Higuet D. Insertion Hot Spots of DIRS1 Retrotransposon and Chromosomal Diversifications among the Antarctic Teleosts Nototheniidae. Int J Mol Sci 2019; 20:ijms20030701. [PMID: 30736325 PMCID: PMC6387122 DOI: 10.3390/ijms20030701] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 01/30/2019] [Accepted: 02/03/2019] [Indexed: 12/17/2022] Open
Abstract
By their faculty to transpose, transposable elements are known to play a key role in eukaryote genomes, impacting both their structuration and remodeling. Their integration in targeted sites may lead to recombination mechanisms involved in chromosomal rearrangements. The Antarctic fish family Nototheniidae went through several waves of species radiations. It is a suitable model to study transposable element (TE)-mediated mechanisms associated to genome and chromosomal diversifications. After the characterization of Gypsy (GyNoto), Copia (CoNoto), and DIRS1 (YNoto) retrotransposons in the genomes of Nototheniidae (diversity, distribution, conservation), we focused on their chromosome location with an emphasis on the three identified nototheniid radiations (the Trematomus, the plunderfishes, and the icefishes). The strong intrafamily TE conservation and wide distribution across species of the whole family suggest an ancestral acquisition with potential secondary losses in some lineages. GyNoto and CoNoto (including Hydra and GalEa clades) mostly produced interspersed signals along chromosomal arms. On the contrary, insertion hot spots accumulating in localized regions (mainly next to centromeric and pericentromeric regions) highlighted the potential role of YNoto in chromosomal diversifications as facilitator of the fusions which occurred in many nototheniid lineages, but not of the fissions.
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Affiliation(s)
- Juliette Auvinet
- Laboratoire Evolution Paris Seine, Sorbonne Université, CNRS, Univ Antilles, Institut de Biologie Paris Seine (IBPS), F-75005 Paris, France.
| | - Paula Graça
- Laboratoire Evolution Paris Seine, Sorbonne Université, CNRS, Univ Antilles, Institut de Biologie Paris Seine (IBPS), F-75005 Paris, France.
| | - Laura Ghigliotti
- Istituto per lo Studio degli Impatti Antropici e la Sostenibilità in Ambiente Marino (IAS), National Research Council (CNR), 16149 Genoa, Italy.
| | - Eva Pisano
- Istituto per lo Studio degli Impatti Antropici e la Sostenibilità in Ambiente Marino (IAS), National Research Council (CNR), 16149 Genoa, Italy.
| | - Agnès Dettaï
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Museum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, 57, rue Cuvier, 75005 Paris, France.
| | - Catherine Ozouf-Costaz
- Laboratoire Evolution Paris Seine, Sorbonne Université, CNRS, Univ Antilles, Institut de Biologie Paris Seine (IBPS), F-75005 Paris, France.
| | - Dominique Higuet
- Laboratoire Evolution Paris Seine, Sorbonne Université, CNRS, Univ Antilles, Institut de Biologie Paris Seine (IBPS), F-75005 Paris, France.
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Museum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, 57, rue Cuvier, 75005 Paris, France.
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Ceballos SG, Roesti M, Matschiner M, Fernández DA, Damerau M, Hanel R, Salzburger W. Phylogenomics of an extra-Antarctic notothenioid radiation reveals a previously unrecognized lineage and diffuse species boundaries. BMC Evol Biol 2019; 19:13. [PMID: 30630407 PMCID: PMC6327445 DOI: 10.1186/s12862-019-1345-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 01/02/2019] [Indexed: 02/03/2023] Open
Abstract
Background The impressive adaptive radiation of notothenioid fishes in Antarctic waters is generally thought to have been facilitated by an evolutionary key innovation, antifreeze glycoproteins, permitting the rapid evolution of more than 120 species subsequent to the Antarctic glaciation. By way of contrast, the second-most species-rich notothenioid genus, Patagonotothen, which is nested within the Antarctic clade of Notothenioidei, is almost exclusively found in the non-Antarctic waters of Patagonia. While the drivers of the diversification of Patagonotothen are currently unknown, they are unlikely to be related to antifreeze glycoproteins, given that water temperatures in Patagonia are well above freezing point. Here we performed a phylogenetic analysis based on genome-wide single nucleotide polymorphisms (SNPs) derived from restriction site-associated DNA sequencing (RADseq) in a total of twelve Patagonotothen species. Results We present a well-supported, time-calibrated phylogenetic hypothesis including closely and distantly related outgroups, confirming the monophyly of the genus Patagonotothen with an origin approximately 3 million years ago and the paraphyly of both the sister genus Lepidonotothen and the family Notothenidae. Our phylogenomic and population genetic analyses highlight a previously unrecognized linage and provide evidence for shared genetic variation between some closely related species. We also provide a mitochondrial phylogeny showing mitonuclear discordance. Conclusions Based on a combination of phylogenomic and population genomic approaches, we provide evidence for the existence of a new, potentially cryptic, Patagonotothen species, and demonstrate that genetic boundaries between some closely related species are diffuse, likely due to recent introgression and/or incomplete linage sorting. The detected mitonuclear discordance highlights the limitations of relying on a single locus for species barcoding. In addition, our time-calibrated phylogenetic hypothesis shows that the early burst of diversification roughly coincides with the onset of the intensification of Quaternary glacial cycles and that the rate of species accumulation may have been stepwise rather than constant. Our phylogenetic framework not only advances our understanding of the origin of a high-latitude marine radiation, but also provides the basis for the study of the ecology and life history of the genus Patagonotothen, as well as for their conservation and commercial management. Electronic supplementary material The online version of this article (10.1186/s12862-019-1345-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Santiago G Ceballos
- Instituto de Ciencias Polares, Ambiente y Recursos Naturales (ICPA), Universidad Nacional de Tierra del Fuego (UNTDF), Fuegia Basket 251, V9410BXE, Ushuaia, Argentina. .,Centro Austral de Investigaciones Científicas (CADIC-CONICET), Bernardo A Houssay 200, V9410BXE Ushuaia, Ushuaia, Tierra del Fuego, Argentina. .,Zoological Institute, University of Basel, Basel, Switzerland.
| | - Marius Roesti
- Zoological Institute, University of Basel, Basel, Switzerland.,Department of Zoology, University of British Columbia, Vancouver, BC, Canada
| | - Michael Matschiner
- Zoological Institute, University of Basel, Basel, Switzerland.,Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, Oslo, Norway
| | - Daniel A Fernández
- Instituto de Ciencias Polares, Ambiente y Recursos Naturales (ICPA), Universidad Nacional de Tierra del Fuego (UNTDF), Fuegia Basket 251, V9410BXE, Ushuaia, Argentina.,Centro Austral de Investigaciones Científicas (CADIC-CONICET), Bernardo A Houssay 200, V9410BXE Ushuaia, Ushuaia, Tierra del Fuego, Argentina
| | - Malte Damerau
- Forestry and Fisheries, Institute of Fisheries Ecology, Johann Heinrich von Thünen Institute, Federal Research Institute for Rural Areas, Hamburg, Germany
| | - Reinhold Hanel
- Forestry and Fisheries, Institute of Fisheries Ecology, Johann Heinrich von Thünen Institute, Federal Research Institute for Rural Areas, Hamburg, Germany
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Fabri-Ruiz S, Danis B, David B, Saucède T. Can we generate robust species distribution models at the scale of the Southern Ocean? DIVERS DISTRIB 2018. [DOI: 10.1111/ddi.12835] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Salomé Fabri-Ruiz
- Biogéosciences; UMR 6282 CNRS; Université Bourgogne Franche-Comté; Dijon France
| | - Bruno Danis
- Laboratoire de Biologie Marine; Université Libre de Bruxelles (ULB); Brussels Belgium
| | - Bruno David
- Biogéosciences; UMR 6282 CNRS; Université Bourgogne Franche-Comté; Dijon France
- Muséum national d'Histoire naturelle; Paris France
| | - Thomas Saucède
- Biogéosciences; UMR 6282 CNRS; Université Bourgogne Franche-Comté; Dijon France
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27
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Russo R, Giordano D, Paredi G, Marchesani F, Milazzo L, Altomonte G, Del Canale P, Abbruzzetti S, Ascenzi P, di Prisco G, Viappiani C, Fago A, Bruno S, Smulevich G, Verde C. The Greenland shark Somniosus microcephalus-Hemoglobins and ligand-binding properties. PLoS One 2017; 12:e0186181. [PMID: 29023598 PMCID: PMC5638460 DOI: 10.1371/journal.pone.0186181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 09/26/2017] [Indexed: 11/18/2022] Open
Abstract
A large amount of data is currently available on the adaptive mechanisms of polar bony fish hemoglobins, but structural information on those of cartilaginous species is scarce. This study presents the first characterisation of the hemoglobin system of one of the longest-living vertebrate species (392 ± 120 years), the Arctic shark Somniosus microcephalus. Three major hemoglobins are found in its red blood cells and are made of two copies of the same α globin combined with two copies of three very similar β subunits. The three hemoglobins show very similar oxygenation and carbonylation properties, which are unaffected by urea, a very important compound in marine elasmobranch physiology. They display identical electronic absorption and resonance Raman spectra, indicating that their heme-pocket structures are identical or highly similar. The quaternary transition equilibrium between the relaxed (R) and the tense (T) states is more dependent on physiological allosteric effectors than in human hemoglobin, as also demonstrated in polar teleost hemoglobins. Similar to other cartilaginous fishes, we found no evidence for functional differentiation among the three isoforms. The very similar ligand-binding properties suggest that regulatory control of O2 transport may be at the cellular level and that it may involve changes in the cellular concentrations of allosteric effectors and/or variations of other systemic factors. The hemoglobins of this polar shark have evolved adaptive decreases in O2 affinity in comparison to temperate sharks.
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Affiliation(s)
- Roberta Russo
- Institute of Biosciences and BioResources, CNR, Via Pietro Castellino 111, Naples, Italy
| | - Daniela Giordano
- Institute of Biosciences and BioResources, CNR, Via Pietro Castellino 111, Naples, Italy
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy
| | - Gianluca Paredi
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parco Area delle Scienze 23/A, Parma, Italy
| | - Francesco Marchesani
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parco Area delle Scienze 23/A, Parma, Italy
| | - Lisa Milazzo
- Dipartimento di Chimica “Ugo Schiff”, Università di Firenze, Via della Lastruccia 3–13, Sesto Fiorentino (FI), Italy
| | - Giovanna Altomonte
- Institute of Biosciences and BioResources, CNR, Via Pietro Castellino 111, Naples, Italy
- Dipartimento di Biologia, Università Roma 3, Viale Marconi 448, Roma, Italy
| | - Pietro Del Canale
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Università degli Studi di Parma, Parco Area delle Scienze 7A, Parma, Italy
| | - Stefania Abbruzzetti
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Università degli Studi di Parma, Parco Area delle Scienze 7A, Parma, Italy
- NEST Istituto Nanoscienze, CNR, Piazza San Silvestro 12, Pisa, Italy
| | - Paolo Ascenzi
- Laboratorio Interdipartimentale di Microscopia Elettronica, Università RomaTre, Via della Vasca Navale 79, Roma, Italy
| | - Guido di Prisco
- Institute of Biosciences and BioResources, CNR, Via Pietro Castellino 111, Naples, Italy
| | - Cristiano Viappiani
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Università degli Studi di Parma, Parco Area delle Scienze 7A, Parma, Italy
- NEST Istituto Nanoscienze, CNR, Piazza San Silvestro 12, Pisa, Italy
| | - Angela Fago
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark
| | - Stefano Bruno
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parco Area delle Scienze 23/A, Parma, Italy
| | - Giulietta Smulevich
- Dipartimento di Chimica “Ugo Schiff”, Università di Firenze, Via della Lastruccia 3–13, Sesto Fiorentino (FI), Italy
| | - Cinzia Verde
- Institute of Biosciences and BioResources, CNR, Via Pietro Castellino 111, Naples, Italy
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy
- Dipartimento di Biologia, Università Roma 3, Viale Marconi 448, Roma, Italy
- * E-mail: ,
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Unusual Antioxidant Properties of 26S Proteasome Isolated from Cold-Adapted Organisms. Int J Mol Sci 2017; 18:ijms18081605. [PMID: 28757562 PMCID: PMC5577997 DOI: 10.3390/ijms18081605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 07/10/2017] [Accepted: 07/18/2017] [Indexed: 11/17/2022] Open
Abstract
The oxidative challenge represents an important factor affecting the adaptive strategies in Antarctic fish, but their impact on the protein degradation machinery still remains unclear. The previous analysis of the first 26S proteasome from the Antarctic red-blooded fish Trematomus bernacchii, evidenced improved antioxidant functions necessary to counteract the environmental pro-oxidant conditions. The purpose of this work was to carry out a study on 26S proteasomes from the temperate red-blooded Dicenthrarcus labrax and the icefish Chionodraco hamatus in comparison with the isoform already described from T. bernacchii, to better elucidate the cold-adapted physiological functions of this complex. Therefore, the 26S isoforms were isolated and the complementary DNAs (cDNAs) codifying the catalytic subunits were cloned. The biochemical characterization of Antarctic 26S proteasomes revealed their significantly higher structural stability and resistance to H2O2 with respect to that of the temperate counterpart, as also suggested by a comparative modeling analysis of the catalytic subunits. Moreover, in contrast to that observed in T. bernacchii, the 26S systems from C. hamatus and D. labrax were incapable to hydrolyze oxidized proteins in a ubiquitin-independent manner. Therefore, the ‘uncommon’ properties displayed by the Antarctic 26S proteasomes can mirror the impact exercised by evolutionary pressure in response to richly oxygenated environments.
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Cold Fusion: Massive Karyotype Evolution in the Antarctic Bullhead Notothen Notothenia coriiceps. G3-GENES GENOMES GENETICS 2017; 7:2195-2207. [PMID: 28576775 PMCID: PMC5498148 DOI: 10.1534/g3.117.040063] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Half of all vertebrate species share a series of chromosome fusions that preceded the teleost genome duplication (TGD), but we do not understand the causative evolutionary mechanisms. The "Robertsonian-translocation hypothesis" suggests a regular fusion of each ancestral acro- or telocentric chromosome to just one other by centromere fusions, thus halving the karyotype. An alternative "genome-stirring hypothesis" posits haphazard and repeated fusions, inversions, and reciprocal and nonreciprocal translocations. To study large-scale karyotype reduction, we investigated the decrease of chromosome numbers in Antarctic notothenioid fish. Most notothenioids have 24 haploid chromosomes, but bullhead notothen (Notothenia coriiceps) has 11. To understand mechanisms, we made a RAD-tag meiotic map with ∼10,000 polymorphic markers. Comparative genomics aligned about a thousand orthologs of platyfish and stickleback genes along bullhead chromosomes. Results revealed that 9 of 11 bullhead chromosomes arose by fusion of just two ancestral chromosomes and two others by fusion of three ancestral chromosomes. All markers from each ancestral chromosome remained contiguous, implying no inversions across fusion borders. Karyotype comparisons support a history of: (1) Robertsonian fusions of 22 ancestral chromosomes in pairs to yield 11 fused plus two small unfused chromosomes, like N. angustata; (2) fusion of one of the remaining two ancestral chromosomes to a preexisting fused pair, giving 12 chromosomes like N. rossii; and (3) fusion of the remaining ancestral chromosome to another fused pair, giving 11 chromosomes in N. coriiceps These results raise the question of what selective forces promoted the systematic fusion of chromosomes in pairs and the suppression of pericentric inversions in this lineage, and provide a model for chromosome fusions in stem teleosts.
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Lillywhite HB, Shine R, Jacobson E, DeNardo DF, Gordon MS, Navas CA, Wang T, Seymour RS, Storey KB, Heatwole H, Heard D, Brattstrom B, Burghardt GM. Anesthesia and Euthanasia of Amphibians and Reptiles Used in Scientific Research: Should Hypothermia and Freezing Be Prohibited? Bioscience 2016. [DOI: 10.1093/biosci/biw143] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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Desvignes T, Detrich HW, Postlethwait JH. Genomic conservation of erythropoietic microRNAs (erythromiRs) in white-blooded Antarctic icefish. Mar Genomics 2016; 30:27-34. [PMID: 27189439 PMCID: PMC5108692 DOI: 10.1016/j.margen.2016.04.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Revised: 04/27/2016] [Accepted: 04/27/2016] [Indexed: 01/03/2023]
Abstract
White-blooded Antarctic crocodile icefish are the only vertebrates known to lack functional hemoglobin genes and red blood cells throughout their lives. We do not yet know, however, whether extinction of hemoglobin genes preceded loss of red blood cells or vice versa, nor whether erythropoiesis regulators disappeared along with hemoglobin genes in this erythrocyte-null clade. Several microRNAs, which we here call erythromiRs, are expressed primarily in developing red blood cells in zebrafish, mouse, and humans. Abrogating some erythromiRs, like mir144 and mir451a, leads to profound anemia, demonstrating a functional role in erythropoiesis. Here, we tested two not mutually exclusive hypotheses: 1) that the loss of one or more erythromiR genes extinguished the erythropoietic program of icefish and/or led to the loss of globin gene expression through pseudogenization; and 2) that some erythromiR genes were secondarily lost after the loss of functional hemoglobin and red blood cells in icefish. We explored small RNA transcriptomes generated from the hematopoietic kidney marrow of four Antarctic notothenioids: two red-blooded species (bullhead notothen Notothenia coriiceps and emerald notothen Trematomus bernacchii) and two white-blooded icefish (blackfin icefish Chaenocephalus aceratus and hooknose icefish Chionodraco hamatus). The N. coriiceps genome assembly anchored analyses. Results showed that, like the two red-blooded species, the blackfin icefish genome possessed and the marrow expressed all known erythromiRs. This result indicates that loss of hemoglobin and red blood cells in icefish was not caused by loss of known erythromiR genes. Furthermore, expression of only one erythromiR, mir96, appears to have been lost after the loss of red blood cells and hemoglobin-expression was not detected in the erythropoietic organ of hooknose icefish but was present in blackfin icefish. All other erythromiRs investigated, including mir144 and mir451a, were expressed by all four species and thus are present in the genomes of at least the two white-blooded icefish. Our results rule out the hypothesis that genomic loss of any known erythromiRs extinguished erythropoiesis in icefish, and suggest that after the loss of red blood cells, few erythromiRs experienced secondary loss. Results suggest that functions independent of erythropoiesis maintained erythromiRs, thereby highlighting the evolutionary resilience of miRNA genes in vertebrate genomes.
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Affiliation(s)
- Thomas Desvignes
- Institute of Neuroscience, University of Oregon, Eugene, OR, 97403, USA.
| | - H William Detrich
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA, 01908, USA.
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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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Prudent X, Parra G, Schwede P, Roscito JG, Hiller M. Controlling for Phylogenetic Relatedness and Evolutionary Rates Improves the Discovery of Associations Between Species' Phenotypic and Genomic Differences. Mol Biol Evol 2016; 33:2135-50. [PMID: 27222536 PMCID: PMC4948712 DOI: 10.1093/molbev/msw098] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The growing number of sequenced genomes allows us now to address a key question in genetics and evolutionary biology: which genomic changes underlie particular phenotypic changes between species? Previously, we developed a computational framework called Forward Genomics that associates phenotypic to genomic differences by focusing on phenotypes that are independently lost in different lineages. However, our previous implementation had three main limitations. Here, we present two new Forward Genomics methods that overcome these limitations by (1) directly controlling for phylogenetic relatedness, (2) controlling for differences in evolutionary rates, and (3) computing a statistical significance. We demonstrate on large-scale simulated data and on real data that both new methods substantially improve the sensitivity to detect associations between phenotypic and genomic differences. We applied these new methods to detect genomic differences involved in the loss of vision in the blind mole rat and the cape golden mole, two independent subterranean mammals. Forward Genomics identified several genes that are enriched in functions related to eye development and the perception of light, as well as genes involved in the circadian rhythm. These new Forward Genomics methods represent a significant advance in our ability to discover the genomic basis underlying phenotypic differences between species. Source code: https://github.com/hillerlab/ForwardGenomics/.
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Affiliation(s)
- Xavier Prudent
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Genis Parra
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Peter Schwede
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Juliana G Roscito
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Michael Hiller
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
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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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O'Brien KM. New Lessons from an Old Fish: What Antarctic Icefishes May Reveal about the Functions of Oxygen-Binding Proteins. Integr Comp Biol 2016; 56:531-41. [PMID: 27252192 DOI: 10.1093/icb/icw062] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The loss of expression of the oxygen-binding protein hemoglobin (Hb) in the family Channichthyidae (suborder Notothenioidei) of Antarctic fishes is considered a disaptation that has persisted because of the unusual conditions prevailing in the Southern Ocean during the evolution of the family. The loss of expression of the intracellular oxygen-binding protein myoglobin (Mb) in heart ventricles is more of a conundrum because it occurred at four points during the radiation of the family, suggesting weakened selective pressure maintaining expression of the protein. Yet, studies have shown that when present, Mb enhances function. Here, I discuss potential reasons for weakened selective pressure maintaining Mb expression in light of the multiple functions proposed for Mb. Additionally, I discuss results from recent studies exploring the possibility that the loss of Hb and Mb may be advantageous because it reduces the production of reactive oxygen species, levels of oxidized proteins, and the energetic costs associated with replacing oxidatively damaged proteins.
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Affiliation(s)
- Kristin M O'Brien
- University of Alaska Fairbanks, Institute of Arctic Biology, Department of Biology and Wildlife, Fairbanks, AK 99775, USA
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Uncommon functional properties of the first piscine 26S proteasome from the Antarctic notothenioid Trematomus bernacchii. Biosci Rep 2016; 36:BSR20160022. [PMID: 26933238 PMCID: PMC4832319 DOI: 10.1042/bsr20160022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 02/15/2016] [Indexed: 12/17/2022] Open
Abstract
The antioxidant defense mechanisms have a great impact on the life of Antarctic organisms. The present study could represent the first evidence of a direct involvement of the 26S proteasome in the antioxidant defense systems of fish adapted to cold. Protein homoeostasis is a fundamental process allowing the preservation of functional proteins and it has a great impact on the life of the Antarctic organisms. However, the effect of low temperatures on protein turnover is poorly understood and the cold-adaptation of the degradation machinery remains an unresolved issue. As the 26S proteasome represents the main proteolytic system devoted to the controlled degradation of intracellular proteins, the purpose of the present study was to investigate the functions of this complex in the notothenioid Trematomus bernacchii, in order to better understand its role in the physiology of Antarctic fish. To this aim, we purified and characterized the 26S proteasome from T. bernacchii and isolated the cDNAs codifying seven of the 14 subunits belonging to the proteasome 20S core particle. Results provided evidences of the high resistance of the piscine 26S proteasome to oxidative agents and of its ‘uncommon’ ability to efficiently hydrolyse oxidized bovine serum albumin (BSA), suggesting that this enzymatic complex could play a key role in the antioxidant defense systems in fish inhabiting permanently cold marine environments. These unique properties were also reflected by the 3D model analysis, which revealed a higher structural stability of the piscine complex respect to the murine template. Finally, a comparative analysis, performed in a variety of tissues collected from T. bernacchii and the temperate fish Dicentrarchus labrax, showed a lower protein retention in the cold-adapted fish, possibly due to a better efficiency of its degradation machinery.
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Assemblage characteristics and diet of fish in the shallow coastal waters of James Ross Island, Antarctica. Polar Biol 2016. [DOI: 10.1007/s00300-016-1896-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Devor DP, Kuhn DE, O'Brien KM, Crockett EL. Hyperoxia Does Not Extend Critical Thermal Maxima (CTmax) in White- or Red-Blooded Antarctic Notothenioid Fishes. Physiol Biochem Zool 2015; 89:1-9. [PMID: 27082520 DOI: 10.1086/684812] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Understanding what limits the capacity of organisms to tolerate increasing temperatures is a critical objective in comparative biology. Using an experimental system of Antarctic notothenioid fishes, we sought to determine whether a mismatch between oxygen demand and oxygen supply was responsible for setting thermal tolerance limits. Previous studies have shown that Antarctic icefishes (family Channichthyidae), which lack hemoglobin, have lower critical thermal maxima (CTmax) than red-blooded notothenioids collected from the same region of the Antarctic (Western Antarctic Peninsula). In addition, within the notothenioid fishes there exists a positive correlation between CTmax and hematocrit. We tested the hypothesis that the lower CTmax of icefishes is associated with reduced oxygen supply. We employed an experimental heat ramp (4°C h(-1)) to determine CTmax under both normoxic and hyperoxic conditions and quantified correlates of oxygen limitation (lactate levels and expression of hypoxia-inducible factor-1α) in white-blooded Chaenocephalus aceratus and red-blooded Notothenia coriiceps. Hyperoxia, corresponding to a three- to fourfold increase in seawater Po2, did not extend CTmax in either species despite an overall mitigation in the rise of plasma and muscle lactate compared with the normoxic treatment. Our results also indicate that cardiac HIF-1α mRNA levels were insensitive to changes in both temperature and oxygen treatments. The absence of a change in CTmax with hyperoxia is likely to represent the contribution of factors beyond oxygen supply to physiological failure at elevated temperatures.
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Papetti C, Harms L, Windisch HS, Frickenhaus S, Sandersfeld T, Jürgens J, Koschnick N, Knust R, Pörtner HO, Lucassen M. A first insight into the spleen transcriptome of the notothenioid fish Lepidonotothen nudifrons: Resource description and functional overview. Mar Genomics 2015; 24 Pt 3:237-9. [DOI: 10.1016/j.margen.2015.06.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 06/08/2015] [Accepted: 06/08/2015] [Indexed: 11/26/2022]
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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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Colombo M, Damerau M, Hanel R, Salzburger W, Matschiner M. Diversity and disparity through time in the adaptive radiation of Antarctic notothenioid fishes. J Evol Biol 2015; 28:376-94. [PMID: 25495187 PMCID: PMC4407914 DOI: 10.1111/jeb.12570] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 12/03/2014] [Accepted: 12/08/2014] [Indexed: 01/30/2023]
Abstract
According to theory, adaptive radiation is triggered by ecological opportunity that can arise through the colonization of new habitats, the extinction of antagonists or the origin of key innovations. In the course of an adaptive radiation, diversification and morphological evolution are expected to slow down after an initial phase of rapid adaptation to vacant ecological niches, followed by speciation. Such 'early bursts' of diversification are thought to occur because niche space becomes increasingly filled over time. The diversification of Antarctic notothenioid fishes into over 120 species has become one of the prime examples of adaptive radiation in the marine realm and has likely been triggered by an evolutionary key innovation in the form of the emergence of antifreeze glycoproteins. Here, we test, using a novel time-calibrated phylogeny of 49 species and five traits that characterize notothenioid body size and shape as well as buoyancy adaptations and habitat preferences, whether the notothenioid adaptive radiation is compatible with an early burst scenario. Extensive Bayesian model comparison shows that phylogenetic age estimates are highly dependent on model choice and that models with unlinked gene trees are generally better supported and result in younger age estimates. We find strong evidence for elevated diversification rates in Antarctic notothenioids compared to outgroups, yet no sign of rate heterogeneity in the course of the radiation, except that the notothenioid family Artedidraconidae appears to show secondarily elevated diversification rates. We further observe an early burst in trophic morphology, suggesting that the notothenioid radiation proceeds in stages similar to other prominent examples of adaptive radiation.
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Affiliation(s)
- M Colombo
- Zoological Institute, University of BaselBasel, Switzerland
| | - M Damerau
- Thünen Institute of Fisheries EcologyHamburg, Germany
| | - R Hanel
- Thünen Institute of Fisheries EcologyHamburg, Germany
| | - W Salzburger
- Zoological Institute, University of BaselBasel, Switzerland
- Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of OsloOslo, Norway
| | - M Matschiner
- Zoological Institute, University of BaselBasel, Switzerland
- Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of OsloOslo, Norway
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Low level of genetic divergence between Harpagifer fish species (Perciformes: Notothenioidei) suggests a Quaternary colonization of Patagonia from the Antarctic Peninsula. Polar Biol 2014. [DOI: 10.1007/s00300-014-1623-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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43
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Sex determination in Antarctic notothenioid fish: chromosomal clues and evolutionary hypotheses. Polar Biol 2014. [DOI: 10.1007/s00300-014-1601-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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44
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Braasch I, Peterson SM, Desvignes T, McCluskey BM, Batzel P, Postlethwait JH. A new model army: Emerging fish models to study the genomics of vertebrate Evo-Devo. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2014; 324:316-41. [PMID: 25111899 DOI: 10.1002/jez.b.22589] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 06/19/2014] [Accepted: 06/25/2014] [Indexed: 01/08/2023]
Abstract
Many fields of biology--including vertebrate Evo-Devo research--are facing an explosion of genomic and transcriptomic sequence information and a multitude of fish species are now swimming in this "genomic tsunami." Here, we first give an overview of recent developments in sequencing fish genomes and transcriptomes that identify properties of fish genomes requiring particular attention and propose strategies to overcome common challenges in fish genomics. We suggest that the generation of chromosome-level genome assemblies--for which we introduce the term "chromonome"--should be a key component of genomic investigations in fish because they enable large-scale conserved synteny analyses that inform orthology detection, a process critical for connectivity of genomes. Orthology calls in vertebrates, especially in teleost fish, are complicated by divergent evolution of gene repertoires and functions following two rounds of genome duplication in the ancestor of vertebrates and a third round at the base of teleost fish. Second, using examples of spotted gar, basal teleosts, zebrafish-related cyprinids, cavefish, livebearers, icefish, and lobefin fish, we illustrate how next generation sequencing technologies liberate emerging fish systems from genomic ignorance and transform them into a new model army to answer longstanding questions on the genomic and developmental basis of their biodiversity. Finally, we discuss recent progress in the genetic toolbox for the major fish models for functional analysis, zebrafish, and medaka, that can be transferred to many other fish species to study in vivo the functional effect of evolutionary genomic change as Evo-Devo research enters the postgenomic era.
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Affiliation(s)
- Ingo Braasch
- Institute of Neuroscience, University of Oregon, Eugene, Oregon
| | | | | | | | - Peter Batzel
- Institute of Neuroscience, University of Oregon, Eugene, Oregon
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Xiao Q, Xia JH, Zhang XJ, Li Z, Wang Y, Zhou L, Gui JF. Type-IV antifreeze proteins are essential for epiboly and convergence in gastrulation of zebrafish embryos. Int J Biol Sci 2014; 10:715-32. [PMID: 25013380 PMCID: PMC4081606 DOI: 10.7150/ijbs.9126] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Accepted: 05/18/2014] [Indexed: 12/17/2022] Open
Abstract
Many organisms in extremely cold environments such as the Antarctic Pole have evolved antifreeze molecules to prevent ice formation. There are four types of antifreeze proteins (AFPs). Type-IV antifreeze proteins (AFP4s) are present also in certain temperate and even tropical fish, which has raised a question as to whether these AFP4s have important functions in addition to antifreeze activity. Here we report the identification and functional analyses of AFP4s in cyprinid fish. Two genes, namely afp4a and afp4b coding for AFP4s, were identified in gibel carp (Carassius auratus gibelio) and zebrafish (Danio rerio). In both species, afp4a and afp4b display a head-to-tail tandem arrangement and share a common 4-exonic gene structure. In zebrafish, both afp4a and afp4b were found to express specifically in the yolk syncytial layer (YSL). Interestingly, afp4a expression continues in YSL and digestive system from early embryos to adults, whereas afp4b expression is restricted to embryogenesis. Importantly, we have shown by using afp4a-specific and afp4b-specifc morpholino knockdown and cell lineage tracing approaches that AFP4a participates in epiboly progression by stabilizing yolk cytoplasmic layer microtubules, and AFP4b is primarily related to convergence movement. Therefore, both AFP4 proteins are essential for gastrulation of zebrafish embryos. Our current results provide first evidence that AFP such as AFP4 has important roles in regulating developmental processes besides its well-known function as antifreeze factors.
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Affiliation(s)
- Qing Xiao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Wuhan 430072, China
| | - Jian-Hong Xia
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Wuhan 430072, China
| | - Xiao-Juan Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Wuhan 430072, China
| | - Zhi Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Wuhan 430072, China
| | - Yang Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Wuhan 430072, China
| | - Li Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Wuhan 430072, China
| | - Jian-Fang Gui
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Wuhan 430072, China
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Ferrando S, Castellano L, Gallus L, Ghigliotti L, Masini MA, Pisano E, Vacchi M. A demonstration of nesting in two antarctic icefish (genus Chionodraco) using a fin dimorphism analysis and ex situ videos. PLoS One 2014; 9:e90512. [PMID: 24598889 PMCID: PMC3944016 DOI: 10.1371/journal.pone.0090512] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 02/01/2014] [Indexed: 11/19/2022] Open
Abstract
Visual observations and videos of Chionodraco hamatus icefish at the “Acquario di Genova” and histological analyses of congeneric species C. hamatus and C. rastrospinosus adults sampled in the field provided new anatomical and behavioral information on the reproductive biology of these white blooded species that are endemic to the High-Antarctic region. During the reproductive season, mature males of both species, which are different from females and immature males, display fleshy, club-like knob modifications of their anal fin that consisted of a much thicker epithelium. Histology indicated that the knobs were without any specialized glandular or sensorial organization, thus suggesting a mechanical and/or ornamental role of the modified anal fin. In addition, the occurrence of necrotic regions at the base of the thickened epithelium and the detachment of the knobs in post-spawning C. hamatus males indicated the temporary nature of the knobs. The role of these structures was confirmed as mechanical and was clarified using visual observations and videos of the behavior of two C. hamatus during a reproductive event that occurred in an exhibit tank at the “Acquario di Genova”. The reproductive process included pre-spawning activity, preparation of the nest, egg guarding and successfully ended with egg hatching. When the spawning event approached, the male prepared the nest. The nest was constructed on an accurately selected bottom surface, which was flattened and maintained free from sand or debris by a combination of radial body movements and continuous anal fin sweeping, thus demonstrating the important mechanical/abrasive function of the anal fin knobs. The present data are the first records of active nesting in icefish and clarify the meaning of dimorphic temporary structures, whose function would have been difficult to obtain in the field.
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Affiliation(s)
- Sara Ferrando
- Department of Earth, Environmental and Life Science (DiSTAV), University of Genoa, Genoa, Italy
| | | | - Lorenzo Gallus
- Department of Earth, Environmental and Life Science (DiSTAV), University of Genoa, Genoa, Italy
| | - Laura Ghigliotti
- Department of Earth, Environmental and Life Science (DiSTAV), University of Genoa, Genoa, Italy
| | - Maria Angela Masini
- Department of Earth, Environmental and Life Science (DiSTAV), University of Genoa, Genoa, Italy
| | - Eva Pisano
- Department of Earth, Environmental and Life Science (DiSTAV), University of Genoa, Genoa, Italy
| | - Marino Vacchi
- Institute for Environmental Protection and Research (ISPRA) c/o Institute of Marine Sciences (ISMAR), National Research Council, Genoa, Italy
- * E-mail:
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Applebaum SL, Ginsburg DW, Capron CS, Manahan DT. Expression of amino acid transporter genes in developmental stages and adult tissues of Antarctic echinoderms. Polar Biol 2013. [DOI: 10.1007/s00300-013-1345-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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48
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49
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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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50
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In situ gene mapping of two genes supports independent evolution of sex chromosomes in cold-adapted Antarctic fish. BIOMED RESEARCH INTERNATIONAL 2013; 2013:243938. [PMID: 23509694 PMCID: PMC3583050 DOI: 10.1155/2013/243938] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 12/03/2012] [Accepted: 12/17/2012] [Indexed: 11/17/2022]
Abstract
Two genes, that is, 5S ribosomal sequences and antifreeze glycoprotein (AFGP) genes, were mapped onto chromosomes of eight Antarctic notothenioid fish possessing a X1X1X2X2/X1X2Y sex chromosome system, namely, Chionodraco hamatus and Pagetopsis macropterus (family Channichthyidae), Trematomus hansoni, T. newnesi, T. nicolai, T. lepidorhinus, and Pagothenia borchgrevinki (family Nototheniidae), and Artedidraco skottsbergi (family Artedidraconidae). Through fluorescence in situ hybridization (FISH), we uncovered distinct differences in the gene content of the Y chromosomes in the eight species, with C. hamatus and P. macropterus standing out among others in bearing 5S rDNA and AFGP sequences on their Y chromosomes, respectively. Both genes were absent from the Y chromosomes of any analyzed species. The distinct patterns of Y and non-Y chromosome association of the 5S rDNA and AFGP genes in species representing different Antarctic fish families support an independent origin of the sex heterochromosomes in notothenioids with interesting implications for the evolutionary/adaptational history of these fishes living in a cold-stable environment.
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