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Acclimatization of a coral-dinoflagellate mutualism at a CO 2 vent. Commun Biol 2023; 6:66. [PMID: 36653505 PMCID: PMC9849335 DOI: 10.1038/s42003-022-04327-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 12/01/2022] [Indexed: 01/19/2023] Open
Abstract
Ocean acidification caused by shifts in ocean carbonate chemistry resulting from increased atmospheric CO2 concentrations is threatening many calcifying organisms, including corals. Here we assessed autotrophy vs heterotrophy shifts in the Mediterranean zooxanthellate scleractinian coral Balanophyllia europaea acclimatized to low pH/high pCO2 conditions at a CO2 vent off Panarea Island (Italy). Dinoflagellate endosymbiont densities were higher at lowest pH Sites where changes in the distribution of distinct haplotypes of a host-specific symbiont species, Philozoon balanophyllum, were observed. An increase in symbiont C/N ratios was observed at low pH, likely as a result of increased C fixation by higher symbiont cell densities. δ13C values of the symbionts and host tissue reached similar values at the lowest pH Site, suggesting an increased influence of autotrophy with increasing acidification. Host tissue δ15N values of 0‰ strongly suggest that diazotroph N2 fixation is occurring within the coral tissue/mucus at the low pH Sites, likely explaining the decrease in host tissue C/N ratios with acidification. Overall, our findings show an acclimatization of this coral-dinoflagellate mutualism through trophic adjustment and symbiont haplotype differences with increasing acidification, highlighting that some corals are capable of acclimatizing to ocean acidification predicted under end-of-century scenarios.
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Spatafora D, Cattano C, Aglieri G, Quattrocchi F, Turco G, Quartararo G, Dudemaine J, Calosi P, Milazzo M. Limited behavioural effects of ocean acidification on a Mediterranean anemone goby (Gobius incognitus) chronically exposed to elevated CO 2 levels. MARINE ENVIRONMENTAL RESEARCH 2022; 181:105758. [PMID: 36183457 DOI: 10.1016/j.marenvres.2022.105758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 09/15/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
An in situ reciprocal transplant experiment was carried around a volcanic CO2 vent to evaluate the anti-predator responses of an anemone goby species exposed to ambient (∼380 μatm) and high (∼850 μatm) CO2 sites. Overall, the anemone gobies displayed largely unaffected behaviors under high-CO2 conditions suggesting an adaptive potential of Gobius incognitus to ocean acidification (OA) conditions. This is also supported by its 3-fold higher density recorded in the field under high CO2. However, while fish exposed to ambient conditions showed an expected reduction in the swimming activity in the proximity of the predator between the pre- and post-exposure period, no such changes were detected in any of the other treatments where fish experienced acute and long-term high CO2. This may suggest an OA effect on the goby antipredator strategy. Our findings contribute to the ongoing debate over the need for realistic predictions of the impacts of expected increased CO2 concentration on fish, providing evidence from a natural high CO2 system.
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Affiliation(s)
- Davide Spatafora
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, Via Archirafi 28, I-90123, Palermo, Italy; Shimoda Marine Research Centre, Tsukuba University, Shimoda City, Shizuoka 415-0025, Japan.
| | - Carlo Cattano
- Department of Integrative Marine Ecology, Sicily, Stazione Zoologica Anton Dohrn, Lungomare Cristoforo Colombo (complesso Roosevelt), 90149, Palermo, Italy
| | - Giorgio Aglieri
- Department of Integrative Marine Ecology, Sicily, Stazione Zoologica Anton Dohrn, Lungomare Cristoforo Colombo (complesso Roosevelt), 90149, Palermo, Italy
| | - Federico Quattrocchi
- Institute for Marine Biological Resources and Biotechnology (IRBIM), National Research Council CNR, Mazara del Vallo (TP), Italy
| | - Gabriele Turco
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, Via Archirafi 28, I-90123, Palermo, Italy
| | - Giulia Quartararo
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, Via Archirafi 28, I-90123, Palermo, Italy
| | - Jeanne Dudemaine
- Département de Biologie, Chimie et Géographie, Université du Québec à Rimouski, Rimouski, Québec, Canada
| | - Piero Calosi
- Département de Biologie, Chimie et Géographie, Université du Québec à Rimouski, Rimouski, Québec, Canada
| | - Marco Milazzo
- Department of Earth and Marine Sciences (DiSTeM), University of Palermo, Via Archirafi 28, I-90123, Palermo, Italy
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3
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Ecological and Biotechnological Relevance of Mediterranean Hydrothermal Vent Systems. MINERALS 2022. [DOI: 10.3390/min12020251] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Marine hydrothermal systems are a special kind of extreme environments associated with submarine volcanic activity and characterized by harsh chemo-physical conditions, in terms of hot temperature, high concentrations of CO2 and H2S, and low pH. Such conditions strongly impact the living organisms, which have to develop adaptation strategies to survive. Hydrothermal systems have attracted the interest of researchers due to their enormous ecological and biotechnological relevance. From ecological perspective, these acidified habitats are useful natural laboratories to predict the effects of global environmental changes, such as ocean acidification at ecosystem level, through the observation of the marine organism responses to environmental extremes. In addition, hydrothermal vents are known as optimal sources for isolation of thermophilic and hyperthermophilic microbes, with biotechnological potential. This double aspect is the focus of this review, which aims at providing a picture of the ecological features of the main Mediterranean hydrothermal vents. The physiological responses, abundance, and distribution of biotic components are elucidated, by focusing on the necto-benthic fauna and prokaryotic communities recognized to possess pivotal role in the marine ecosystem dynamics and as indicator species. The scientific interest in hydrothermal vents will be also reviewed by pointing out their relevance as source of bioactive molecules.
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Herrera M, Liew YJ, Venn A, Tambutté E, Zoccola D, Tambutté S, Cui G, Aranda M. New Insights From Transcriptomic Data Reveal Differential Effects of CO 2 Acidification Stress on Photosynthesis of an Endosymbiotic Dinoflagellate in hospite. Front Microbiol 2021; 12:666510. [PMID: 34349734 PMCID: PMC8326563 DOI: 10.3389/fmicb.2021.666510] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 06/15/2021] [Indexed: 01/22/2023] Open
Abstract
Ocean acidification (OA) has both detrimental as well as beneficial effects on marine life; it negatively affects calcifiers while enhancing the productivity of photosynthetic organisms. To date, many studies have focused on the impacts of OA on calcification in reef-building corals, a process particularly susceptible to acidification. However, little is known about the effects of OA on their photosynthetic algal partners, with some studies suggesting potential benefits for symbiont productivity. Here, we investigated the transcriptomic response of the endosymbiont Symbiodinium microadriaticum (CCMP2467) in the Red Sea coral Stylophora pistillata subjected to different long-term (2 years) OA treatments (pH 8.0, 7.8, 7.4, 7.2). Transcriptomic analyses revealed that symbionts from corals under lower pH treatments responded to acidification by increasing the expression of genes related to photosynthesis and carbon-concentrating mechanisms. These processes were mostly up-regulated and associated metabolic pathways were significantly enriched, suggesting an overall positive effect of OA on the expression of photosynthesis-related genes. To test this conclusion on a physiological level, we analyzed the symbiont’s photochemical performance across treatments. However, in contrast to the beneficial effects suggested by the observed gene expression changes, we found significant impairment of photosynthesis with increasing pCO2. Collectively, our data suggest that over-expression of photosynthesis-related genes is not a beneficial effect of OA but rather an acclimation response of the holobiont to different water chemistries. Our study highlights the complex effects of ocean acidification on these symbiotic organisms and the role of the host in determining symbiont productivity and performance.
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Affiliation(s)
- Marcela Herrera
- Red Sea Research Center (RSRC), Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Yi Jin Liew
- Red Sea Research Center (RSRC), Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Alexander Venn
- Marine Department, Centre Scientifique de Monaco, Monaco, Monaco
| | - Eric Tambutté
- Marine Department, Centre Scientifique de Monaco, Monaco, Monaco
| | - Didier Zoccola
- Marine Department, Centre Scientifique de Monaco, Monaco, Monaco
| | - Sylvie Tambutté
- Marine Department, Centre Scientifique de Monaco, Monaco, Monaco
| | - Guoxin Cui
- Red Sea Research Center (RSRC), Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Manuel Aranda
- Red Sea Research Center (RSRC), Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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Mishra AK, Cabaço S, de Los Santos CB, Apostolaki ET, Vizzini S, Santos R. Long-term effects of elevated CO 2 on the population dynamics of the seagrass Cymodocea nodosa: Evidence from volcanic seeps. MARINE POLLUTION BULLETIN 2021; 162:111824. [PMID: 33162054 DOI: 10.1016/j.marpolbul.2020.111824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/25/2020] [Accepted: 10/30/2020] [Indexed: 06/11/2023]
Abstract
Population reconstruction techniques was used to assess for the first time the population dynamics of a seagrass, Cymodocea nodosa, exposed to long-term elevated CO2 near three volcanic seeps and compared them with reference sites away from the seeps. Under high CO2, the density of shoots and of individuals (apical shoots), and the vertical and horizontal elongation and production rates, were higher than at the reference sites. Nitrogen limitation effects on rhizome elongation and production rates and on biomass were more evident than CO2 as these were highest at the location where the limitation of nitrogen was highest. At the seep where the availability of CO2 was highest and nitrogen lowest, density of shoots and individuals were highest, probably due to CO2 effects on shoot differentiation and induced reproductive output, respectively. At the three seeps, there was higher short- and long-term shoot recruitment than at the reference sites, and growth rates was around zero, indicating that elevated CO2 increases the turnover of C. nodosa shoots.
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Affiliation(s)
- A K Mishra
- Marine Plant Ecology Research Group (ALGAE), Centre of Marine Sciences (CCMAR), University of Algarve, Faro 8005-139, Portugal; School of Biological and Marine Sciences, Faculty of Science and Engineering, University of Plymouth, Portland Square, Drake Circus, Plymouth PL48LA, UK.
| | - S Cabaço
- Marine Plant Ecology Research Group (ALGAE), Centre of Marine Sciences (CCMAR), University of Algarve, Faro 8005-139, Portugal
| | - C B de Los Santos
- Marine Plant Ecology Research Group (ALGAE), Centre of Marine Sciences (CCMAR), University of Algarve, Faro 8005-139, Portugal
| | - E T Apostolaki
- Institute of Oceanography, Hellenic Center for Marine Research (HCMR), PO Box 2214, 71003 Heraklion-Crete, Greece
| | - S Vizzini
- Department of Earth and Marine Sciences, University of Palermo, via Archirafi 18, 90123 Palermo, Italy; CoNISMa, Piazzale Flaminio 9, 00196 Roma, Italy
| | - R Santos
- Marine Plant Ecology Research Group (ALGAE), Centre of Marine Sciences (CCMAR), University of Algarve, Faro 8005-139, Portugal
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Testing algal-based pCO 2 proxies at a modern CO 2 seep (Vulcano, Italy). Sci Rep 2020; 10:10508. [PMID: 32601284 PMCID: PMC7324594 DOI: 10.1038/s41598-020-67483-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 06/02/2020] [Indexed: 12/03/2022] Open
Abstract
Understanding long-term trends in atmospheric concentrations of carbon dioxide (pCO2) has become increasingly relevant as modern concentrations surpass recent historic trends. One method for estimating past pCO2, the stable carbon isotopic fractionation associated with photosynthesis (Ɛp) has shown promise over the past several decades, in particular using species-specific biomarker lipids such as alkenones. Recently, the Ɛp of more general biomarker lipids, organic compounds derived from a multitude of species, have been applied to generate longer-spanning, more ubiquitous records than those of alkenones but the sensitivity of this proxy to changes in pCO2 has not been constrained in modern settings. Here, we test Ɛp using a variety of general biomarkers along a transect taken from a naturally occurring marine CO2 seep in Levante Bay of the Aeolian island of Vulcano in Italy. The studied general biomarkers, loliolide, cholesterol, and phytol, all show increasing depletion in 13C over the transect from the control site towards the seep, suggesting that CO2 exerts a strong control on isotopic fractionation in natural phytoplankton communities. The strongest shift in fractionation was seen in phytol, and pCO2 estimates derived from phytol confirm the utility of this biomarker as a proxy for pCO2 reconstruction.
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7
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Urbarova I, Forêt S, Dahl M, Emblem Å, Milazzo M, Hall-Spencer JM, Johansen SD. Ocean acidification at a coastal CO2 vent induces expression of stress-related transcripts and transposable elements in the sea anemone Anemonia viridis. PLoS One 2019; 14:e0210358. [PMID: 31067218 PMCID: PMC6505742 DOI: 10.1371/journal.pone.0210358] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 04/05/2019] [Indexed: 12/17/2022] Open
Abstract
Ocean acidification threatens to disrupt interactions between organisms throughout marine ecosystems. The diversity of reef-building organisms decreases as seawater CO2 increases along natural gradients, yet soft-bodied animals, such as sea anemones, are often resilient. We sequenced the polyA-enriched transcriptome of adult sea anemone Anemonia viridis and its dinoflagellate symbiont sampled along a natural CO2 gradient in Italy to assess stress levels in these organisms. We found that about 1.4% of the anemone transcripts, but only ~0.5% of the Symbiodinium sp. transcripts were differentially expressed. Processes enriched at high seawater CO2 were mainly linked to cellular stress, including significant up-regulation of protective cellular functions and deregulation of metabolic pathways. Transposable elements were differentially expressed at high seawater CO2, with an extreme up-regulation (> 100-fold) of the BEL-family of long terminal repeat retrotransposons. Seawater acidified by CO2 generated a significant stress reaction in A. viridis, but no bleaching was observed and Symbiodinium sp. appeared to be less affected. These observed changes indicate the mechanisms by which A. viridis acclimate to survive chronic exposure to ocean acidification conditions. We conclude that many organisms that are common in acidified conditions may nevertheless incur costs due to hypercapnia and/or lowered carbonate saturation states.
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Affiliation(s)
- Ilona Urbarova
- Department of Medical Biology, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway
- * E-mail: (IU); (SDJ)
| | - Sylvain Forêt
- Evolution, Ecology and Genetics, Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Mikael Dahl
- Department of Medical Biology, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Åse Emblem
- Department of Medical Biology, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Marco Milazzo
- Department of Earth and Marine Sciences, University of Palermo, Palermo, Italy
| | - Jason M. Hall-Spencer
- School of Biological and Marine Science, University of Plymouth, Plymouth, United Kingdom
- Shimoda Marine Research Center, University of Tsukuba, Shimoda City, Shizuoka, Japan
| | - Steinar D. Johansen
- Department of Medical Biology, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway
- Genomics Research Group, Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
- * E-mail: (IU); (SDJ)
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8
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Vizzini S, Apostolaki ET, Ricevuto E, Polymenakou P, Mazzola A. Plant and sediment properties in seagrass meadows from two Mediterranean CO 2 vents: Implications for carbon storage capacity of acidified oceans. MARINE ENVIRONMENTAL RESEARCH 2019; 146:101-108. [PMID: 30929836 DOI: 10.1016/j.marenvres.2019.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 03/05/2019] [Accepted: 03/10/2019] [Indexed: 06/09/2023]
Abstract
Assessing the status of important carbon sinks such as seagrass meadows is of primary importance when dealing with potential climate change mitigation strategies. This study examined plant and sediment properties in seagrass meadows (Cymodocea nodosa (Ucria) Asch.) from two high pCO2-low pH Mediterranean vent systems, located at Milos (Greece) and Vulcano (Italy) Islands, providing insights on carbon storage potential in future acidified oceans. Contrary to what has been suggested, carbon content (both inorganic and organic) and its surficial accumulation decreased at high pCO2-low pH in comparison with controls. The decrease in inorganic carbon may result from the higher solubility of carbonates due to the more acidic conditions. At Vulcano, the seagrass properties (e.g., leaf area, biomass) appeared negatively affected by environmental conditions at high pCO2-low pH conditions and this may have had a detrimental effect on the organic carbon content and accumulation. At Milos, organic carbon decreased at high pCO2-low pH conditions, despite the increase in seagrass aboveground biomass, leaf length and area, probably as a consequence of site-specific features, which need further investigation and may include both biotic and abiotic factors (e.g., oligotrophic conditions, decreased sedimentation rate and input of allochthonous material). Results suggest that, in contrast to previous predictions based exclusively on the expected positive response of seagrasses to ocean acidification, carbon storage capacity of the seagrass C. nodosa may not increase at high pCO2-low pH conditions. This study emphasizes the need to investigate further the potential alteration in the climate mitigation service delivered by seagrass meadows in acidified oceans.
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Affiliation(s)
- Salvatrice Vizzini
- Department of Earth and Marine Sciences, University of Palermo, Via Archirafi 18, 90123, Palermo, Italy; National Inter-University Consortium for Marine Sciences, CoNISMa, Piazzale Flaminio 9, 00196, Roma, Italy.
| | - Eugenia T Apostolaki
- Institute of Oceanography, Hellenic Centre for Marine Research, PO Box 2214, GR-71003, Heraklion, Crete, Greece
| | - Elena Ricevuto
- Department of Earth and Marine Sciences, University of Palermo, Via Archirafi 18, 90123, Palermo, Italy
| | - Paraskevi Polymenakou
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research, PO Box 2214, GR-71003, Heraklion, Crete, Greece
| | - Antonio Mazzola
- Department of Earth and Marine Sciences, University of Palermo, Via Archirafi 18, 90123, Palermo, Italy; National Inter-University Consortium for Marine Sciences, CoNISMa, Piazzale Flaminio 9, 00196, Roma, Italy
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9
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Ferrier‐Pagès C, Leal MC. Stable isotopes as tracers of trophic interactions in marine mutualistic symbioses. Ecol Evol 2019; 9:723-740. [PMID: 30680151 PMCID: PMC6342181 DOI: 10.1002/ece3.4712] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 09/17/2018] [Accepted: 10/26/2018] [Indexed: 12/31/2022] Open
Abstract
Mutualistic nutritional symbioses are widespread in marine ecosystems. They involve the association of a host organism (algae, protists, or marine invertebrates) with symbiotic microorganisms, such as bacteria, cyanobacteria, or dinoflagellates. Nutritional interactions between the partners are difficult to identify in symbioses because they only occur in intact associations. Stable isotope analysis (SIA) has proven to be a useful tool to highlight original nutrient sources and to trace nutrients acquired by and exchanged between the different partners of the association. However, although SIA has been extensively applied to study different marine symbiotic associations, there is no review taking into account of the different types of symbiotic associations, how they have been studied via SIA, methodological issues common among symbiotic associations, and solutions that can be transferred from one type of association with another. The present review aims to fill such gaps in the scientific literature by summarizing the current knowledge of how isotopes have been applied to key marine symbioses to unravel nutrient exchanges between partners, and by describing the difficulties in interpreting the isotopic signal. This review also focuses on the use of compound-specific stable isotope analysis and on statistical advances to analyze stable isotope data. It also highlights the knowledge gaps that would benefit from future research.
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Affiliation(s)
| | - Miguel Costa Leal
- MARE – Marine and Environmental Sciences CentreFaculdade de Ciências da Universidade de LisboaLisbonPortugal
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10
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Urbarova I, Patel H, Forêt S, Karlsen BO, Jørgensen TE, Hall-Spencer JM, Johansen SD. Elucidating the Small Regulatory RNA Repertoire of the Sea Anemone Anemonia viridis Based on Whole Genome and Small RNA Sequencing. Genome Biol Evol 2018; 10:410-426. [PMID: 29385567 PMCID: PMC5793845 DOI: 10.1093/gbe/evy003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2018] [Indexed: 12/16/2022] Open
Abstract
Cnidarians harbor a variety of small regulatory RNAs that include microRNAs (miRNAs) and PIWI-interacting RNAs (piRNAs), but detailed information is limited. Here, we report the identification and expression of novel miRNAs and putative piRNAs, as well as their genomic loci, in the symbiotic sea anemone Anemonia viridis. We generated a draft assembly of the A. viridis genome with putative size of 313 Mb that appeared to be composed of about 36% repeats, including known transposable elements. We detected approximately equal fractions of DNA transposons and retrotransposons. Deep sequencing of small RNA libraries constructed from A. viridis adults sampled at a natural CO2 gradient off Vulcano Island, Italy, identified 70 distinct miRNAs. Eight were homologous to previously reported miRNAs in cnidarians, whereas 62 appeared novel. Nine miRNAs were recognized as differentially expressed along the natural seawater pH gradient. We found a highly abundant and diverse population of piRNAs, with a substantial fraction showing ping–pong signatures. We identified nearly 22% putative piRNAs potentially targeting transposable elements within the A. viridis genome. The A. viridis genome appeared similar in size to that of other hexacorals with a very high divergence of transposable elements resembling that of the sea anemone genus Exaiptasia. The genome encodes and expresses a high number of small regulatory RNAs, which include novel miRNAs and piRNAs. Differentially expressed small RNAs along the seawater pH gradient indicated regulatory gene responses to environmental stressors.
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Affiliation(s)
- Ilona Urbarova
- Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, Tromsø, Norway
| | - Hardip Patel
- Genomics and Predictive Medicine, Genome Biology Department, John Curtin School of Medical Research, ANU College of Medicine, Biology, and Environment, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Sylvain Forêt
- Evolution, Ecology, and Genetics, Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Bård Ove Karlsen
- Research Laboratory, Department of Laboratory Medicine, Nordland Hospital, Bodø, Norway
| | - Tor Erik Jørgensen
- Genomics Group, Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Jason M Hall-Spencer
- Marine Biology and Ecology Research Centre, University of Plymouth, United Kingdom.,Shimoda Marine Research Centre, University of Tsukuba, Shimoda City, Shizuoka, Japan
| | - Steinar D Johansen
- Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, Tromsø, Norway.,Genomics Group, Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
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11
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Klein SG, Pitt KA, Nitschke MR, Goyen S, Welsh DT, Suggett DJ, Carroll AR. Symbiodinium mitigate the combined effects of hypoxia and acidification on a noncalcifying cnidarian. GLOBAL CHANGE BIOLOGY 2017; 23:3690-3703. [PMID: 28390081 DOI: 10.1111/gcb.13718] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 03/28/2017] [Accepted: 04/02/2017] [Indexed: 05/23/2023]
Abstract
Anthropogenic nutrient inputs enhance microbial respiration within many coastal ecosystems, driving concurrent hypoxia and acidification. During photosynthesis, Symbiodinium spp., the microalgal endosymbionts of cnidarians and other marine phyla, produce O2 and assimilate CO2 and thus potentially mitigate the exposure of the host to these stresses. However, such a role for Symbiodinium remains untested for noncalcifying cnidarians. We therefore contrasted the fitness of symbiotic and aposymbiotic polyps of a model host jellyfish (Cassiopea sp.) under reduced O2 (~2.09 mg/L) and pH (~ 7.63) scenarios in a full-factorial experiment. Host fitness was characterized as asexual reproduction and their ability to regulate internal pH and Symbiodinium performance characterized by maximum photochemical efficiency, chla content and cell density. Acidification alone resulted in 58% more asexual reproduction of symbiotic polyps than aposymbiotic polyps (and enhanced Symbiodinium cell density) suggesting Cassiopea sp. fitness was enhanced by CO2 -stimulated Symbiodinium photosynthetic activity. Indeed, greater CO2 drawdown (elevated pH) was observed within host tissues of symbiotic polyps under acidification regardless of O2 conditions. Hypoxia alone produced 22% fewer polyps than ambient conditions regardless of acidification and symbiont status, suggesting Symbiodinium photosynthetic activity did not mitigate its effects. Combined hypoxia and acidification, however, produced similar numbers of symbiotic polyps compared with aposymbiotic kept under ambient conditions, demonstrating that the presence of Symbiodinium was key for mitigating the combined effects of hypoxia and acidification on asexual reproduction. We hypothesize that this mitigation occurred because of reduced photorespiration under elevated CO2 conditions where increased net O2 production ameliorates oxygen debt. We show that Symbiodinium play an important role in facilitating enhanced fitness of Cassiopea sp. polyps, and perhaps also other noncalcifying cnidarian hosts, to the ubiquitous effects of ocean acidification. Importantly we highlight that symbiotic, noncalcifying cnidarians may be particularly advantaged in productive coastal waters that are subject to simultaneous hypoxia and acidification.
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Affiliation(s)
- Shannon G Klein
- Australian Rivers Institute - Coasts and Estuaries, Griffith School of Environment, Griffith University, Gold Coast, Qld, Australia
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Kylie A Pitt
- Australian Rivers Institute - Coasts and Estuaries, Griffith School of Environment, Griffith University, Gold Coast, Qld, Australia
| | - Matthew R Nitschke
- Climate Change Cluster (C3), University of Technology Sydney, Sydney, NSW, Australia
| | - Samantha Goyen
- Climate Change Cluster (C3), University of Technology Sydney, Sydney, NSW, Australia
| | - David T Welsh
- Environmental Futures Research Institute, Griffith School of Environment, Griffith University, Gold Coast, Qld, Australia
| | - David J Suggett
- Climate Change Cluster (C3), University of Technology Sydney, Sydney, NSW, Australia
| | - Anthony R Carroll
- Environmental Futures Research Institute, Griffith School of Environment, Griffith University, Gold Coast, Qld, Australia
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12
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Muller EM, Fine M, Ritchie KB. The stable microbiome of inter and sub-tidal anemone species under increasing pCO 2. Sci Rep 2016; 6:37387. [PMID: 27876762 PMCID: PMC5120257 DOI: 10.1038/srep37387] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 10/28/2016] [Indexed: 01/18/2023] Open
Abstract
Increasing levels of pCO2 within the oceans will select for resistant organisms such as anemones, which may thrive under ocean acidification conditions. However, increasing pCO2 may alter the bacterial community of marine organisms, significantly affecting the health status of the host. A pH gradient associated with a natural volcanic vent system within Levante Bay, Vulcano Island, Italy, was used to test the effects of ocean acidification on the bacterial community of two anemone species in situ, Anemonia viridis and Actinia equina using 16 S rDNA pyrosequencing. Results showed the bacterial community of the two anemone species differed significantly from each other primarily because of differences in the Gammaproteobacteria and Epsilonproteobacteria abundances. The bacterial communities did not differ within species among sites with decreasing pH except for A. viridis at the vent site (pH = 6.05). In addition to low pH, the vent site contains trace metals and sulfide that may have influenced the bacteria community of A. viridis. The stability of the bacterial community from pH 8.1 to pH 7.4, coupled with previous experiments showing the lack of, or beneficial changes within anemones living under low pH conditions indicates that A. viridis and A. equina will be winners under future ocean acidification scenarios.
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Affiliation(s)
| | - Maoz Fine
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
- The Interuniversity Institute of Marine Science in Eilat, P.O.B. 469 Eilat 88103, Israel
| | - Kim B. Ritchie
- Mote Marine Laboratory, Sarasota, FL 34236, USA
- The University of South Carolina, Beaufort SC 29902, USA
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