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Bartels N, Matthews JL, Lawson CA, Possell M, Hughes DJ, Raina JB, Suggett DJ. Paired metabolomics and volatilomics provides insight into transient high light stress response mechanisms of the coral Montipora mollis. Metabolomics 2024; 20:66. [PMID: 38886248 PMCID: PMC11182861 DOI: 10.1007/s11306-024-02136-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Accepted: 05/27/2024] [Indexed: 06/20/2024]
Abstract
The coral holobiont is underpinned by complex metabolic exchanges between different symbiotic partners, which are impacted by environmental stressors. The chemical diversity of the compounds produced by the holobiont is high and includes primary and secondary metabolites, as well as volatiles. However, metabolites and volatiles have only been characterised in isolation so far. Here, we applied a paired metabolomic-volatilomic approach to characterise holistically the chemical response of the holobiont under stress. Montipora mollis fragments were subjected to high-light stress (8-fold higher than the controls) for 30 min. Photosystem II (PSII) photochemical efficiency values were 7-fold higher in control versus treatment corals immediately following high-light exposure, but returned to pre-stress levels after 30 min of recovery. Under high-light stress, we identified an increase in carbohydrates (> 5-fold increase in arabinose and fructose) and saturated fatty acids (7-fold increase in myristic and oleic acid), together with a decrease in fatty acid derivatives in both metabolites and volatiles (e.g., 80% decrease in oleamide and nonanal), and other antioxidants (~ 85% decrease in sorbitol and galactitol). These changes suggest short-term light stress induces oxidative stress. Correlation analysis between volatiles and metabolites identified positive links between sorbitol, galactitol, six other metabolites and 11 volatiles, with four of these compounds previously identified as antioxidants. This suggests that these 19 compounds may be related and share similar functions. Taken together, our findings demonstrate how paired metabolomics-volatilomics may illuminate broader metabolic shifts occurring under stress and identify linkages between uncharacterised compounds to putatively determine their functions.
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Affiliation(s)
- Natasha Bartels
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia.
| | - Jennifer L Matthews
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Caitlin A Lawson
- Heron Island Research Station, Faculty of Science, University of Queensland, Gladstone, 4680, Australia
| | - Malcolm Possell
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - David J Hughes
- National Sea Simulator, Australian Institute of Marine Science, Townsville, QLD, Australia
| | - Jean-Baptiste Raina
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - David J Suggett
- KAUST Reefscape Restoration Initiative (KRRI) and Red Sea Research Center (RSRC), King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
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2
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Helgoe J, Davy SK, Weis VM, Rodriguez-Lanetty M. Triggers, cascades, and endpoints: connecting the dots of coral bleaching mechanisms. Biol Rev Camb Philos Soc 2024; 99:715-752. [PMID: 38217089 DOI: 10.1111/brv.13042] [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: 03/02/2023] [Revised: 12/08/2023] [Accepted: 12/12/2023] [Indexed: 01/15/2024]
Abstract
The intracellular coral-dinoflagellate symbiosis is the engine that underpins the success of coral reefs, one of the most diverse ecosystems on the planet. However, the breakdown of the symbiosis and the loss of the microalgal symbiont (i.e. coral bleaching) due to environmental changes are resulting in the rapid degradation of coral reefs globally. There is an urgent need to understand the cellular physiology of coral bleaching at the mechanistic level to help develop solutions to mitigate the coral reef crisis. Here, at an unprecedented scope, we present novel models that integrate putative mechanisms of coral bleaching within a common framework according to the triggers (initiators of bleaching, e.g. heat, cold, light stress, hypoxia, hyposalinity), cascades (cellular pathways, e.g. photoinhibition, unfolded protein response, nitric oxide), and endpoints (mechanisms of symbiont loss, e.g. apoptosis, necrosis, exocytosis/vomocytosis). The models are supported by direct evidence from cnidarian systems, and indirectly through comparative evolutionary analyses from non-cnidarian systems. With this approach, new putative mechanisms have been established within and between cascades initiated by different bleaching triggers. In particular, the models provide new insights into the poorly understood connections between bleaching cascades and endpoints and highlight the role of a new mechanism of symbiont loss, i.e. 'symbiolysosomal digestion', which is different from symbiophagy. This review also increases the approachability of bleaching physiology for specialists and non-specialists by mapping the vast landscape of bleaching mechanisms in an atlas of comprehensible and detailed mechanistic models. We then discuss major knowledge gaps and how future research may improve the understanding of the connections between the diverse cascade of cellular pathways and the mechanisms of symbiont loss (endpoints).
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Affiliation(s)
- Joshua Helgoe
- Department of Biological Sciences, Institute of Environment, Florida International University, 11200 SW 8th Street, OE 167, Miami, FL, USA
| | - Simon K Davy
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, New Zealand
| | - Virginia M Weis
- Department of Integrative Biology, Oregon State University, 2701 SW Campus Way, 2403 Cordley Hall, Corvallis, OR, USA
| | - Mauricio Rodriguez-Lanetty
- Department of Biological Sciences, Institute of Environment, Florida International University, 11200 SW 8th Street, OE 167, Miami, FL, USA
- Department of Biological Sciences, Biomolecular Sciences Institute, Florida International University, 11200 SW 8th Street, Miami, FL, USA
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3
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Ishibashi H, Nishimura S, Tanaka K, Haruta S, Takayama K, Yamashiro H, Takeuchi I. Transcriptome analysis reveals limited toxic effects of the UV-filter benzophenone-3 (BP-3) on the hermatypic coral Acropora tenuis and its symbiotic dinoflagellates. MARINE POLLUTION BULLETIN 2024; 201:116260. [PMID: 38522341 DOI: 10.1016/j.marpolbul.2024.116260] [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: 12/17/2023] [Revised: 02/22/2024] [Accepted: 03/11/2024] [Indexed: 03/26/2024]
Abstract
This study aimed to investigate the toxic and transcriptomic effects of the ultraviolet filter benzophenone-3 (BP-3) on Acropora tenuis and its symbiotic dinoflagellates while using acetone as a solvent. Seven-day exposure to 50 and 500 μg/L, which is higher than most BP-3 records from coastal waters, did not affect coral colour or dinoflagellate photosynthesis. Differentially expressed genes (DEGs) between seawater and solvent controls were <20 in both corals and dinoflagellates. Eleven coral DEGs were detected after treatment with 50 μg/L BP-3. Fourteen coral DEGs, including several fluorescent protein genes, were detected after treatment with 500 μg/L BP-3. In contrast, no dinoflagellate DEGs were detected in the BP-3 treatment group. These results suggest that the effects of 50-500 μg/L BP-3 on adult A. tenuis and its dinoflagellates are limited. Our experimental methods with lower acetone toxicity provide a basis for establishing standard ecotoxicity tests for corals.
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Affiliation(s)
- Hiroshi Ishibashi
- Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan; Center of Advanced Technology for the Environment, Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan
| | - Saori Nishimura
- Faculty of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan
| | - Kokoro Tanaka
- Faculty of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan
| | - Shinsuke Haruta
- Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan; Center of Advanced Technology for the Environment, Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan
| | - Kotaro Takayama
- Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan; Center of Advanced Technology for the Environment, Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan
| | - Hideyuki Yamashiro
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa, Japan
| | - Ichiro Takeuchi
- Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan; Center of Advanced Technology for the Environment, Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan.
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4
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Jia S, Geng X, Cai Z, Wang Y, Shen J, Li Y, Wu Z, Chen S, Wang D. Comparison of physiological and transcriptome responses of corals to strong light and high temperature. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 273:116143. [PMID: 38430582 DOI: 10.1016/j.ecoenv.2024.116143] [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: 08/29/2023] [Revised: 02/17/2024] [Accepted: 02/20/2024] [Indexed: 03/04/2024]
Abstract
Coral reefs are essential for marine ecology and biodiversity. Global climate change has resulted in severe coral reef degradation, partly via coral bleaching, which is caused by rising sea temperatures and solar light intensity. In this study, we examined the impact of strong light (300 µmol.m-2.s-1) and high temperature (33°C) on the growth, immunity, and gene expression of Galaxea fascicularis. Strong light caused coral bleaching in the absence of high sea temperatures, while no obvious bleaching was observed under high temperature alone. The effect of strong light on calcification rate of G. fascicularis is significantly weaker than that of high temperature. Both strong light and high temperatures significantly affected the immune enzyme activity of G. fascicularis symbionts, with the former having a strong effect on their photosystem. Temperature affected the digestive system, replication and repair, and cell growth and death of coral hosts, as indicated by transcriptomics analysis. These results provide a valuable for strategies to mitigate coral bleaching. TEASER: We explored the effects of strong light exposure and high temperature on coral reefs and their symbiont algae.
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Affiliation(s)
- Shuwen Jia
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China
| | - Xiaoxiao Geng
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China
| | - Zefu Cai
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China
| | - Yi Wang
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China
| | - Jie Shen
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China
| | - Yuanchao Li
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China
| | - Zhongjie Wu
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China
| | - Shiquan Chen
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China.
| | - Daoru Wang
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571136, China; Key Laboratory for Coastal Marine Eco-Environment Process and Carbon Sink of Hainan province, Yazhou Bay Innovation Institute, College of Ecology and Environment, Hainan Tropical Ocean University, Sanya 572000, China; Key laboratory of Utilization and Conservation for Tropical Marine Bioresources (Hainan Tropical Ocean University), Ministry of Education, Sanya 572022, China.
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5
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Zhou Y, Li Q, Zhang Q, Yuan M, Zhu X, Li Y, Li Q, Downs CA, Huang D, Chou LM, Zhao H. Environmental Concentrations of Herbicide Prometryn Render Stress-Tolerant Corals Susceptible to Ocean Warming. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:4545-4557. [PMID: 38386019 DOI: 10.1021/acs.est.3c10417] [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: 02/23/2024]
Abstract
Global warming has caused the degradation of coral reefs around the world. While stress-tolerant corals have demonstrated the ability to acclimatize to ocean warming, it remains unclear whether they can sustain their thermal resilience when superimposed with other coastal environmental stressors. We report the combined impacts of a photosystem II (PSII) herbicide, prometryn, and ocean warming on the stress-tolerant coral Galaxea fascicularis through physiological and omics analyses. The results demonstrate that the heat-stress-induced inhibition of photosynthetic efficiency in G. fascicularis is exacerbated in the presence of prometryn. Transcriptomics and metabolomics analyses indicate that the prometryn exposure may overwhelm the photosystem repair mechanism in stress-tolerant corals, thereby compromising their capacity for thermal acclimation. Moreover, prometryn might amplify the adverse effects of heat stress on key energy and nutrient metabolism pathways and induce a stronger response to oxidative stress in stress-tolerant corals. The findings indicate that the presence of prometryn at environmentally relevant concentrations would render corals more susceptible to heat stress and exacerbate the breakdown of coral Symbiodiniaceae symbiosis. The present study provides valuable insights into the necessity of prioritizing PSII herbicide pollution reduction in coral reef protection efforts while mitigating the effects of climate change.
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Affiliation(s)
- Yanyu Zhou
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, China
- Center for Eco-Environment Restoration of Hainan Province & Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environment and Ecology, Hainan University, Haikou 570228, China
| | - Qiuli Li
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, China
- Center for Eco-Environment Restoration of Hainan Province & Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environment and Ecology, Hainan University, Haikou 570228, China
| | - Quan Zhang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310032, China
| | - Meile Yuan
- Center for Eco-Environment Restoration of Hainan Province & Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environment and Ecology, Hainan University, Haikou 570228, China
| | - Xiaoshan Zhu
- Center for Eco-Environment Restoration of Hainan Province & Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environment and Ecology, Hainan University, Haikou 570228, China
| | - Yuanchao Li
- Hainan Academy of Ocean and Fisheries Sciences, Haikou 571126, China
| | - Qipei Li
- Center for Eco-Environment Restoration of Hainan Province & Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environment and Ecology, Hainan University, Haikou 570228, China
| | - Craig A Downs
- Haereticus Environmental Laboratory, P.O. Box 92, Clifford, Virginia 24533, United States
| | - Danwei Huang
- Lee Kong Chian Natural History Museum, National University of Singapore, Singapore 117377, Singapore
- Tropical Marine Science Institute, National University of Singapore, Singapore 119227, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Loke-Ming Chou
- Tropical Marine Science Institute, National University of Singapore, Singapore 119227, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Hongwei Zhao
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, China
- Center for Eco-Environment Restoration of Hainan Province & Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environment and Ecology, Hainan University, Haikou 570228, China
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6
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Murthy MHS, Jasbi P, Lowe W, Kumar L, Olaosebikan M, Roger L, Yang J, Lewinski N, Daniels N, Cowen L, Klein-Seetharaman J. Insulin signaling and pharmacology in humans and in corals. PeerJ 2024; 12:e16804. [PMID: 38313028 PMCID: PMC10838073 DOI: 10.7717/peerj.16804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 12/27/2023] [Indexed: 02/06/2024] Open
Abstract
Once thought to be a unique capability of the Langerhans islets in the pancreas of mammals, insulin (INS) signaling is now recognized as an evolutionarily ancient function going back to prokaryotes. INS is ubiquitously present not only in humans but also in unicellular eukaryotes, fungi, worms, and Drosophila. Remote homologue identification also supports the presence of INS and INS receptor in corals where the availability of glucose is largely dependent on the photosynthetic activity of the symbiotic algae. The cnidarian animal host of corals operates together with a 20,000-sized microbiome, in direct analogy to the human gut microbiome. In humans, aberrant INS signaling is the hallmark of metabolic disease, and is thought to play a major role in aging, and age-related diseases, such as Alzheimer's disease. We here would like to argue that a broader view of INS beyond its human homeostasis function may help us understand other organisms, and in turn, studying those non-model organisms may enable a novel view of the human INS signaling system. To this end, we here review INS signaling from a new angle, by drawing analogies between humans and corals at the molecular level.
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Affiliation(s)
| | - Paniz Jasbi
- School of Molecular Sciences, Arizona State University, Phoenix, AZ, USA
| | - Whitney Lowe
- Departments of Chemistry & Physics, Colorado School of Mines, Golden, CO, United States
| | - Lokender Kumar
- Departments of Chemistry & Physics, Colorado School of Mines, Golden, CO, United States
| | | | - Liza Roger
- School of Molecular Sciences, Arizona State University, Phoenix, AZ, USA
- School of Ocean Futures, Arizona State University, Tempe, AZ, United States of America
| | - Jinkyu Yang
- Department of Aeronautics & Astronautics, University of Washington, Seattle, WA, USA
| | - Nastassja Lewinski
- Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Noah Daniels
- Department of Computer Science, University of Rhode Island, Kingston, RI, USA
| | - Lenore Cowen
- Department of Computer Science, Tufts University, Medford, MA, USA
| | - Judith Klein-Seetharaman
- School of Molecular Sciences, Arizona State University, Phoenix, AZ, USA
- Departments of Chemistry & Physics, Colorado School of Mines, Golden, CO, United States
- College of Health Solutions, Arizona State University, Phoenix, AZ, United States
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7
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Downie AT, Cramp RL, Franklin CE. The interactive impacts of a constant reef stressor, ultraviolet radiation, with environmental stressors on coral physiology. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:168066. [PMID: 37890630 DOI: 10.1016/j.scitotenv.2023.168066] [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: 02/05/2023] [Revised: 07/19/2023] [Accepted: 10/21/2023] [Indexed: 10/29/2023]
Abstract
Reef-building corals create one of the most biodiverse and economically important ecosystems on the planet. Unfortunately, global coral reef ecosystems experience threats from numerous natural stressors, which are amplified by human activities. One such threat is ultraviolet radiation (UVR) from the sun; a genotoxic stressor that is a double-edged sword for corals as they rely on sunlight for energy. More intense UVR has been shown to have greater direct impacts on animal physiology, and these may be exacerbated by co-occurring stressors. The aim of this systematic literature review was to examine if the same applies to corals; that is, if the co-exposure of a constant stressor (UVR) with other stressors has a greater impact on coral physiology than if these stressors occurred separately. We reviewed the biochemical and cellular processes impacted by UVR and the defenses corals have against UVR. The main stressors investigated with UVR were temperature, nitrate, nutrient, oil, water motion, and photosynthetically active radiation (PAR). UVR generally worsened the physiological impacts of other stressors (e.g., by decreasing zooxanthellae and chlorophyll densities). There were species-specific differences in their tolerance to UVR (differences in zooxanthellae populations, sunscreen production and depth) and environmental stress (e.g., resilience to some oils), and that ambient levels of UVR were often beneficial (i.e., nullifying impacts of nitrates). We highlight areas of future investigation including examining and assessing other interacting stressors and their impacts (e.g., ocean acidification, ocean deoxygenation, toxins and pollutants), investigating impacts of multiple stressors with UVR on the coral microbiome, and elucidating the effects of multi-stressors with UVR across early-life history stages (especially larvae). UVR is a pervasive stressor to corals and can interact with other environmental conditions to compromise the resilience of corals. This environmental driver needs to be more comprehensively examined alongside climate change stressors (e.g., temperature increases, ocean acidification and hypoxia) to better understand future climate scenarios on reefs.
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Affiliation(s)
- Adam T Downie
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia.
| | - Rebecca L Cramp
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Craig E Franklin
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia
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8
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Doust SN, Haghshenas SA, Bishop EE, Risk MJ, Downs CA. Fine-scale geographic risk assessment of oxybenzone sunscreen pollution within Hanauma Bay using hydrodynamic characterization and modeling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167614. [PMID: 37804976 DOI: 10.1016/j.scitotenv.2023.167614] [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: 08/22/2023] [Revised: 09/20/2023] [Accepted: 10/04/2023] [Indexed: 10/09/2023]
Abstract
Hanauma Bay's coral reef system is threatened by sunscreen pollution. Understanding the hydrodynamic nature of the bay is crucial for understanding the transport and fate of pollutants within the bay. This study conducted a comprehensive hydrodynamic analysis, revealing significant aspects of current patterns and their influence on sunscreen pollutant behavior. The analysis demonstrated the formation of flows that drive currents parallel to the shoreline, resulting in increased pollutant retention time over sensitive reef areas. Direct flushing currents were identified as playing a role in reducing pollution buildup. Particle dynamics analysis highlighted the importance of considering temporal dynamics and their implications for pollutant pathways, particularly through the swash zone during high tide phases. The study identified primary current patterns near the reef area and emphasized the circular behavior within the water body, affecting corals' susceptibility to bleaching in the southwestern part of Hanauma bay. To understand where oxybenzone concentrations were a threat to wildlife, we created a geographic model that integrated ecological risk assessment with hydrodynamic behavior in a given system, which we designate the Risk Quotient Plume - the geographic area where the concentration is above the threat level for a chemical. The study found high oxybenzone concentrations throughout the bay, threatening coral, fish, and algae populations. Oxybenzone's distribution indicated a serious threat to the entire back reef habitat and a hinderance to coral restoration efforts. The study also emphasizes the need to consider the hydrodynamic behavior of pollutants and their interaction with microplastics in the bay. Overall, the findings provide insights into hydrodynamics and pollutant dispersion in Hanauma Bay, supporting effective pollution management and conservation strategies.
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Affiliation(s)
- Shadan Nasseri Doust
- Institute of Geophysics, University of Tehran, North Kargar Ave., Tehran 1439951113, Islamic Republic of Iran
| | - S Abbas Haghshenas
- Institute of Geophysics, University of Tehran, North Kargar Ave., Tehran 1439951113, Islamic Republic of Iran.
| | - Elizabeth E Bishop
- Friends of Hanauma Bay, P.O. Box 25761, Honolulu, HI 96825-07610, United States of America
| | - Michael J Risk
- School of Geography and Geology, McMaster University, N0G 1R0, Canada
| | - C A Downs
- Haereticus Environmental Laboratory, P.O. Box 92, Clifford, VA 24533, United States of America.
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9
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Zhang J, Huang Z, Li Y, Fu D, Li Q, Pei L, Song Y, Chen L, Zhao H, Kao SJ. Synergistic/antagonistic effects of nitrate/ammonium enrichment on fatty acid biosynthesis and translocation in coral under heat stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162834. [PMID: 36924962 DOI: 10.1016/j.scitotenv.2023.162834] [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: 12/16/2022] [Revised: 03/02/2023] [Accepted: 03/09/2023] [Indexed: 06/18/2023]
Abstract
Superimposed on ocean warming, nitrogen enrichment caused by human activity puts corals under even greater pressure. Biosynthesis of fatty acids (FA) is crucial for coral holobiont survival. However, the responses of FA biosynthesis pathways to nitrogen enrichment under heat stress in coral hosts and Symbiodiniaceae remain unknown, as do FA translocation mechanisms in corals. Herein, we used the thermosensitive coral species Acropora hyacinthus to investigate changes in FA biosynthesis pathways and polyunsaturated FA translocation of coral hosts and Symbiodiniaceae with respect to nitrate and ammonium enrichment under heat stress. Heat stress promoted pro-inflammatory FA biosynthesis in coral hosts and inhibited FA biosynthesis in Symbiodiniaceae. Nitrate enrichment inhibited anti-inflammatory FA biosynthesis in Symbiodiniaceae, and promoted pro-inflammatory FA biosynthesis in coral hosts and translocation to Symbiodiniaceae, leading to bleaching after 14 days of culture. Intriguingly, ammonium enrichment promoted anti-inflammatory FA biosynthesis in Symbiodiniaceae and translocation to hosts, allowing corals to better endure heat stress. We constructed schematic diagrams of the shift in FA biosynthesis and translocation in and between A. hyacinthus and its Symbiodiniaceae under heat stress, heat and nitrate co-stress, and heat and ammonium co-stress. The findings provide insight into the mechanisms of coral bleaching under environmental stress from a fatty acid perspective.
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Affiliation(s)
- Jingjing Zhang
- State Key Laboratory of Marine Resources Utilization in South China Sea, Hainan University, Haikou 570228, China; Haikou Marine Geological Survey Center, China Geological Survey, Haikou 571127, China; Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Center for Eco-Environment Restoration of Hainan Province, College of Ecology and Environment, Hainan University, Haikou 570228, China
| | - Zanhui Huang
- Haikou Marine Geological Survey Center, China Geological Survey, Haikou 571127, China
| | - Yuanchao Li
- Hainan Academy of Marine and Fishery Sciences, Haikou 571126, China
| | - Dinghui Fu
- Haikou Marine Geological Survey Center, China Geological Survey, Haikou 571127, China
| | - Qipei Li
- Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Center for Eco-Environment Restoration of Hainan Province, College of Ecology and Environment, Hainan University, Haikou 570228, China
| | - Lixin Pei
- Haikou Marine Geological Survey Center, China Geological Survey, Haikou 571127, China
| | - Yanwei Song
- Haikou Marine Geological Survey Center, China Geological Survey, Haikou 571127, China
| | - Liang Chen
- Haikou Marine Geological Survey Center, China Geological Survey, Haikou 571127, China
| | - Hongwei Zhao
- State Key Laboratory of Marine Resources Utilization in South China Sea, Hainan University, Haikou 570228, China; Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Center for Eco-Environment Restoration of Hainan Province, College of Ecology and Environment, Hainan University, Haikou 570228, China.
| | - Shuh-Ji Kao
- State Key Laboratory of Marine Resources Utilization in South China Sea, Hainan University, Haikou 570228, China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361101, China
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10
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Lin S, Guo Y, Huang Z, Tang K, Wang X. Comparative Genomic Analysis of Cold-Water Coral-Derived Sulfitobacter faviae: Insights into Their Habitat Adaptation and Metabolism. Mar Drugs 2023; 21:md21050309. [PMID: 37233503 DOI: 10.3390/md21050309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 05/27/2023] Open
Abstract
Sulfitobacter is one of the major sulfite-oxidizing alphaproteobacterial groups and is often associated with marine algae and corals. Their association with the eukaryotic host cell may have important ecological contexts due to their complex lifestyle and metabolism. However, the role of Sulfitobacter in cold-water corals remains largely unexplored. In this study, we explored the metabolism and mobile genetic elements (MGEs) in two closely related Sulfitobacter faviae strains isolated from cold-water black corals at a depth of ~1000 m by comparative genomic analysis. The two strains shared high sequence similarity in chromosomes, including two megaplasmids and two prophages, while both contained several distinct MGEs, including prophages and megaplasmids. Additionally, several toxin-antitoxin systems and other types of antiphage elements were also identified in both strains, potentially helping Sulfitobacter faviae overcome the threat of diverse lytic phages. Furthermore, the two strains shared similar secondary metabolite biosynthetic gene clusters and genes involved in dimethylsulfoniopropionate (DMSP) degradation pathways. Our results provide insight into the adaptive strategy of Sulfitobacter strains to thrive in ecological niches such as cold-water corals at the genomic level.
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Affiliation(s)
- Shituan Lin
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunxue Guo
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Zixian Huang
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaihao Tang
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Xiaoxue Wang
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
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11
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Nielsen DA, Petrou K. Lipid stores reveal the state of the coral-algae symbiosis at the single-cell level. ISME COMMUNICATIONS 2023; 3:29. [PMID: 37016078 PMCID: PMC10073229 DOI: 10.1038/s43705-023-00234-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/14/2023] [Accepted: 03/22/2023] [Indexed: 04/06/2023]
Abstract
Coral reefs worldwide are threatened by environmental stress. The observable decline in coral cover, is principally due to the intensifying breakdown of the coral symbiosis, a process known as 'bleaching'. Overproduction of reactive oxygen species (ROS) is considered a key driver of coral bleaching, where environmental stress leads to increased ROS expression. To explore the link between ROS damage and symbiont status, we measured lipid peroxidation (LPO), a ubiquitous form of ROS damage, in the lipid stores of individual endo- and ex-symbiotic algal cells of three coral species, using confocal microscopy and a lipid hydroperoxide sensitive fluorescent dye. We found LPO was higher in endosymbionts, while lipid volume was greater in ex-symbiotic cells. Cluster analysis revealed three metabolic profiles differentiating endosymbiotic (#1: high LPO, low lipid) and ex-symbiotic cells (#3: low LPO, high lipid), with the intermediate group (#2) containing both cell types. Heat stress caused endosymbionts of Pocillopora acuta to shift away from cluster #1, suggesting this cluster represents cells in healthy/stable symbiosis. Our study delivers a new means to assess the coral symbiosis, demonstrating that symbiont LPO ratio combined with lipid store volume is a robust metabolic marker for the state of the symbiosis at the cellular level.
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Affiliation(s)
| | - Katherina Petrou
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, Australia
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12
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Page CA, Giuliano C, Bay LK, Randall CJ. High survival following bleaching underscores the resilience of a frequently disturbed region of the Great Barrier Reef. Ecosphere 2023. [DOI: 10.1002/ecs2.4280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Affiliation(s)
- Cathie A. Page
- Australian Institute of Marine Science Townsville Queensland Australia
| | | | - Line K. Bay
- Australian Institute of Marine Science Townsville Queensland Australia
| | - Carly J. Randall
- Australian Institute of Marine Science Townsville Queensland Australia
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13
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Solar radiation, temperature and the reproductive biology of the coral Lobactis scutaria in a changing climate. Sci Rep 2023; 13:246. [PMID: 36604569 PMCID: PMC9816315 DOI: 10.1038/s41598-022-27207-6] [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: 07/16/2022] [Accepted: 12/28/2022] [Indexed: 01/07/2023] Open
Abstract
Coral reefs worldwide are at risk due to climate change. Coral bleaching is becoming increasingly common and corals that survive bleaching events can suffer from temporary reproductive failure for several years. While water temperature is a key driver in causing coral bleaching, other environmental factors are involved, such as solar radiation. We investigated the individual and combined effects of temperature, photosynthetically active radiation (PAR), and ultraviolet radiation (UVR) on the spawning patterns and reproductive physiology of the Hawaiian mushroom coral Lobactis scutaria, using long-term experiments in aquaria. We examined effects on spawning timing, fertilisation success, and gamete physiology. Both warmer temperatures and filtering UVR altered the timing of spawning. Warmer temperatures caused a drop in fertilisation success. Warmer temperatures and higher PAR both negatively affected sperm and egg physiology. These results are concerning for the mushroom coral L. scutaria and similar reproductive data are urgently needed to predict future reproductive trends in other species. Nonetheless, thermal stress from global climate change will need to be adequately addressed to ensure the survival of reef-building corals in their natural environment throughout the next century and beyond. Until then, reproduction is likely to be increasingly impaired in a growing number of coral species.
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14
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Rouan A, Pousse M, Tambutté E, Djerbi N, Zozaya W, Capasso L, Zoccola D, Tambutté S, Gilson E. Telomere dysfunction is associated with dark-induced bleaching in the reef coral Stylophora pistillata. Mol Ecol 2022; 31:6087-6099. [PMID: 34587336 DOI: 10.1111/mec.16199] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 08/23/2021] [Accepted: 09/15/2021] [Indexed: 01/31/2023]
Abstract
Telomere DNA length is a complex trait controlled by both multiple loci and environmental factors. A growing number of studies are focusing on the impact of stress and stress accumulation on telomere length and the link with survival and fitness in ecological contexts. Here, we investigated the telomere changes occurring in a symbiotic coral, Stylophora pistillata, that has experienced continuous darkness over 6 months. This stress condition led to the loss of its symbionts in a similar manner to that observed during large-scale bleaching events due to climate changes and anthropogenic activities, threatening reef ecosystems worldwide. We found that continuous darkness was associated with telomere length shortening. This result, together with a phylogenetic analysis of the telomere coral proteins and a transcriptome survey of the continuous darkness condition, paves the way for future studies on the role of telomeres in the coral stress response and the importance of environmentally induced telomere shortening in endangered coral species.
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Affiliation(s)
- Alice Rouan
- Université Côte d'Azur-CNRS-Inserm, IRCAN, Nice, France
| | | | - Eric Tambutté
- Department of Marine Biology, Centre Scientifique de Monaco, Monte Carlo, Principality of Monaco
| | - Nadir Djerbi
- Université Côte d'Azur-CNRS-Inserm, IRCAN, Nice, France
| | | | - Laura Capasso
- Department of Marine Biology, Centre Scientifique de Monaco, Monte Carlo, Principality of Monaco.,Collège Doctoral, Sorbonne Université, Paris, France
| | - Didier Zoccola
- Department of Marine Biology, Centre Scientifique de Monaco, Monte Carlo, Principality of Monaco
| | - Sylvie Tambutté
- Department of Marine Biology, Centre Scientifique de Monaco, Monte Carlo, Principality of Monaco
| | - Eric Gilson
- Université Côte d'Azur-CNRS-Inserm, IRCAN, Nice, France.,Department of Medical Genetics, CHU, Nice, France
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15
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Walker NS, Cornwell BH, Nestor V, Armstrong KC, Golbuu Y, Palumbi SR. Persistence of phenotypic responses to short-term heat stress in the tabletop coral Acropora hyacinthus. PLoS One 2022; 17:e0269206. [PMID: 36084033 PMCID: PMC9462741 DOI: 10.1371/journal.pone.0269206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/23/2022] [Indexed: 12/26/2022] Open
Abstract
Widespread mapping of coral thermal resilience is essential for developing effective management strategies and requires replicable and rapid multi-location assays of heat resistance and recovery. One- or two-day short-term heat stress experiments have been previously employed to assess heat resistance, followed by single assays of bleaching condition. We tested the reliability of short-term heat stress resistance, and linked resistance and recovery assays, by monitoring the phenotypic response of fragments from 101 Acropora hyacinthus colonies located in Palau (Micronesia) to short-term heat stress. Following short-term heat stress, bleaching and mortality were recorded after 16 hours, daily for seven days, and after one and two months of recovery. To follow corals over time, we utilized a qualitative, non-destructive visual bleaching score metric that correlated with standard symbiont retention assays. The bleaching state of coral fragments 16 hours post-heat stress was highly indicative of their state over the next 7 days, suggesting that symbiont population sizes within corals may quickly stabilize post-heat stress. Bleaching 16 hours post-heat stress predicted likelihood of mortality over the subsequent 3–5 days, after which there was little additional mortality. Together, bleaching and mortality suggested that rapid assays of the phenotypic response following short-term heat stress were good metrics of the total heat treatment effect. Additionally, our data confirm geographic patterns of intraspecific variation in Palau and show that bleaching severity among colonies was highly correlated with mortality over the first week post-stress. We found high survival (98%) and visible recovery (100%) two months after heat stress among coral fragments that survived the first week post-stress. These findings help simplify rapid, widespread surveys of heat sensitivity in Acropora hyacinthus by showing that standardized short-term experiments can be confidently assayed after 16 hours, and that bleaching sensitivity may be linked to subsequent survival using experimental assessments.
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Affiliation(s)
- Nia S. Walker
- Department of Biology, Hopkins Marine Station of Stanford University, Pacific Grove, California, United States of America
- * E-mail:
| | - Brendan H. Cornwell
- Department of Biology, Hopkins Marine Station of Stanford University, Pacific Grove, California, United States of America
| | | | - Katrina C. Armstrong
- Department of Biology, Hopkins Marine Station of Stanford University, Pacific Grove, California, United States of America
| | | | - Stephen R. Palumbi
- Department of Biology, Hopkins Marine Station of Stanford University, Pacific Grove, California, United States of America
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16
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Al-Hammady MA, Silva TF, Hussein HN, Saxena G, Modolo LV, Belasy MB, Westphal H, Farag MA. How do algae endosymbionts mediate for their coral host fitness under heat stress? A comprehensive mechanistic overview. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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17
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Poór P, Nawaz K, Gupta R, Ashfaque F, Khan MIR. Ethylene involvement in the regulation of heat stress tolerance in plants. PLANT CELL REPORTS 2022; 41:675-698. [PMID: 33713206 DOI: 10.1007/s00299-021-02675-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 02/14/2021] [Indexed: 05/12/2023]
Abstract
Because of the rise in global temperature, heat stress has become a major concern for crop production. Heat stress deteriorates plant productivity and alters phenological and physiological responses that aid in precise monitoring and sensing of mild-to-severe transient heat stress. Plants have evolved several sophisticated mechanisms including hormone-signaling pathways to sense heat stimuli and acquire heat stress tolerance. In response to heat stress, ethylene, a gaseous hormone, is produced which is indispensable for plant growth and development and tolerance to various abiotic stresses including heat stress. The manipulation of ethylene in developing heat stress tolerance targeting ethylene biosynthesis and signaling pathways has brought promising out comes. Conversely increased ethylene biosynthesis and signaling seem to exhibit inhibitory effects in plant growth responses from primitive to maturity stages. This review mainly focuses on the recent studies of ethylene involvement in plant responses to heat stress and its functional regulation, and molecular mechanism underlying the plant responses in the mitigation of heat-induced damages. Furthermore, this review also describes the crosstalk between ethylene and other signaling molecules under heat stress and approaches to improve heat stress tolerance in plants.
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Affiliation(s)
- Peter Poór
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - Kashif Nawaz
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Kingdom of Saudi Arabia
| | - Ravi Gupta
- Department of Botany, Jamia Hamdard, New Delhi, India
| | - Farha Ashfaque
- Department of Botany, Aligarh Muslim University, Aligarh, India
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18
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Downs CA, Bishop E, Diaz-Cruz MS, Haghshenas SA, Stien D, Rodrigues AMS, Woodley CM, Sunyer-Caldú A, Doust SN, Espero W, Ward G, Farhangmehr A, Tabatabaee Samimi SM, Risk MJ, Lebaron P, DiNardo JC. Oxybenzone contamination from sunscreen pollution and its ecological threat to Hanauma Bay, Oahu, Hawaii, U.S.A. CHEMOSPHERE 2022; 291:132880. [PMID: 34780745 DOI: 10.1016/j.chemosphere.2021.132880] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 10/29/2021] [Accepted: 11/09/2021] [Indexed: 05/20/2023]
Abstract
Hanauma Bay is a 101-acre bay created by the partial collapse of a volcanic cone and once supported a vibrant coral reef system. It is the most popular swimming area in the Hawaiian Islands and has been reported to have averaged between 2.8 and 3.5 million visitors a year between the 1980s and the 2010s, with visitors averaging between 3000-4000 a day and peaking around 10,000-13,000 per day. Concentrations of oxybenzone and other common UV filters were measured in subsurface water samples and in sands from the beach-shower areas in Hanauma Bay. Results demonstrate that beach showers also can be a source of sunscreen environmental contamination. Hydrodynamic modeling indicates that oxybenzone contamination within Hanauma Bay's waters could be retained between 14 and 50 h from a single release event period. Focusing on only oxybenzone, two different Hazard and Risk Assessment analyses were conducted to determine the danger of oxybenzone to Hanauma Bay's coral reef system. Results indicate that oxybenzone contamination poses a significant threat to the wildlife of Hanauma Bay. To recover Hanauma Bay's natural resources to a healthy condition and to satisfactorily conserve its coral reef and sea grass habitats, effective tourism management policies need to be implemented that mitigate the threat of sunscreen pollution.
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Affiliation(s)
- C A Downs
- Haereticus Environmental Laboratory, P.O. Box 92, Clifford, VA, 2453, USA; Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France.
| | - Elizabeth Bishop
- Friends of Hanauma Bay, P.O. Box 25761, Honolulu, HI, 96825-07610, USA
| | - M Silvia Diaz-Cruz
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Severo Ochoa Excellence Center. Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034, Barcelona, Spain
| | | | - Didier Stien
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Alice M S Rodrigues
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Cheryl M Woodley
- U.S. National Oceanic & Atmospheric Administration, National Ocean Service, National Centers for Coastal Ocean Science, Coral Disease & Health Program, Hollings Marine Laboratory, 331 Ft. Johnson Rd. Charleston, SC, 29412, USA
| | - Adrià Sunyer-Caldú
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Severo Ochoa Excellence Center. Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, 08034, Barcelona, Spain
| | | | - William Espero
- Hawaii State Senate, Senate District 19, Hawaii State Capitol, 415 S. Beretania St. Honolulu, HI, 96813, USA
| | - Gene Ward
- Hawaii State Legislature, House District 17, Hawaii State Capitol, 415 S. Beretania St. Honolulu, HI, 96813, USA
| | | | | | - Michael J Risk
- Department of Earth Sciences, McMaster University, Hamilton, Ontario, L8S 4M1, Canada
| | - Philippe Lebaron
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
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19
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Bleaching physiology: who's the 'weakest link' - host vs. symbiont? Emerg Top Life Sci 2022; 6:17-32. [PMID: 35179208 DOI: 10.1042/etls20210228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/20/2022] [Accepted: 02/01/2022] [Indexed: 11/17/2022]
Abstract
Environmental stress, such as an increase in the sea surface temperature, triggers coral bleaching, a profound dysfunction of the mutualist symbiosis between the host cnidarians and their photosynthetic dinoflagellates of the Family Symbiodiniaceae. Because of climate change, mass coral bleaching events will increase in frequency and severity in the future, threatening the persistence of this iconic marine ecosystem at global scale. Strategies adapted to coral reefs preservation and restoration may stem from the identification of the succession of events and of the different molecular and cellular contributors to the bleaching phenomenon. To date, studies aiming to decipher the cellular cascade leading to temperature-related bleaching, emphasized the involvement of reactive species originating from compromised bioenergetic pathways (e.g. cellular respiration and photosynthesis). These molecules are responsible for damage to various cellular components causing the dysregulation of cellular homeostasis and the breakdown of symbiosis. In this review, we synthesize the current knowledge available in the literature on the cellular mechanisms caused by thermal stress, which can initiate or participate in the cell cascade leading to the loss of symbionts, with a particular emphasis on the role of each partner in the initiating processes.
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20
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Zhang Y, Ip JCH, Xie JY, Yeung YH, Sun Y, Qiu JW. Host-symbiont transcriptomic changes during natural bleaching and recovery in the leaf coral Pavona decussata. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150656. [PMID: 34597574 DOI: 10.1016/j.scitotenv.2021.150656] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 09/24/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
Coral bleaching has become a major threat to coral reefs worldwide, but for most coral species little is known about their resilience to environmental changes. We aimed to understand the gene expressional regulation underlying natural bleaching and recovery in Pavona decussata, a dominant species of scleractinian coral in the northern South China Sea. Analyzing samples collected in 2017 from the field revealed distinct zooxanthellae density, chlorophyll a concentration and transcriptomic signatures corresponding to changes in health conditions of the coral holobiont. In the host, normal-looking tissues of partially bleached colonies were frontloaded with stress responsive genes, as indicated by upregulation of immune defense, response to endoplasmic reticulum, and oxidative stress genes. Bleaching was characterized by upregulation of apoptosis-related genes which could cause a reduction in algal symbionts, and downregulation of genes involved in stress responses and metabolic processes. The transcription factors stat5b and irf1 played key roles in bleaching by regulating immune and apoptosis pathways. Recovery from bleaching was characterized by enrichment of pathways involved in mitosis, DNA replication, and recombination for tissue repairing, as well as restoration of energy and metabolism. In the symbionts, bleaching corresponded to imbalance in photosystems I and II activities which enhanced oxidative stress and limited energy production and nutrient assimilation. Overall, our study revealed distinct gene expressional profiles and regulation in the different phases of the bleaching and recovery process, and provided new insight into the molecular mechanisms underlying the holobiont's resilience that may determine the species' fate in response to global and regional environmental changes.
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Affiliation(s)
- Yanjie Zhang
- Department of Biology, Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong Baptist University, Hong Kong, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; State Key Laboratory of Environmental and Biological Analysis, Hong Kong Baptist University, Hong Kong, China
| | - Jack Chi-Ho Ip
- Department of Biology, Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong Baptist University, Hong Kong, China
| | - James Y Xie
- Department of Biology, Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong Baptist University, Hong Kong, China
| | - Yip Hung Yeung
- Department of Biology, Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong Baptist University, Hong Kong, China
| | - Yanan Sun
- Department of Biology, Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong Baptist University, Hong Kong, China
| | - Jian-Wen Qiu
- Department of Biology, Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong Baptist University, Hong Kong, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; State Key Laboratory of Environmental and Biological Analysis, Hong Kong Baptist University, Hong Kong, China.
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21
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Decreased Photosynthetic Efficiency in Response to Site Translocation and Elevated Temperature Is Mitigated with LPS Exposure in Porites astreoides Symbionts. WATER 2022. [DOI: 10.3390/w14030366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Coral reefs have been detrimentally impacted causing health issues due to elevated ocean temperatures as a result of increased greenhouse gases. Extreme temperatures have also exacerbated coral diseases in tropical reef environments. Numerous studies have outlined the impacts of thermal stress and disease on coral organisms, as well as understanding the influence of site-based characteristics on coral physiology. However, few have discussed the interaction of all three. Laboratory out-planting restoration projects have been of importance throughout impacted areas such as the Caribbean and southern Florida in order to increase coral cover in these areas. This study analyzes photosynthetic efficiency of Porites astreoides from the lower Florida Keys after a two-year reciprocal transplant study at inshore (Birthday reef) and offshore (Acer24 reef) sites to understand acclimation capacity of this species. Laboratory experiments subjected these colonies to one of three treatments: control conditions, increases in temperature, and increases in temperature plus exposure to an immune stimulant (lipopolysaccharide (LPS)) to determine their influence on photosynthetic efficiency and how stress events impact these measurements. In addition, this study is a continuation of previous studies from this group. Here, we aim to understand if these results are static or if an acclimation capacity could be found. Overall, we observed site-specific influences from the Acer24 reef site, which had significant decreases in photosynthetic efficiencies in 32 °C treatments compared to Birthday reef colonies. We suggest that high irradiance and lack of an annual recovery period from the Acer24 site exposes these colonies to significant photoinhibition. In addition, we observed significant increases in photosynthetic efficiencies from LPS exposure. We suggest host-derived antioxidants can mitigate the negative impacts of increased thermal stress. Further research is required to understand the full complexity of host immunity and symbiont photosynthetic interactions.
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22
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Lesser MP. Eutrophication on Coral Reefs: What Is the Evidence for Phase Shifts, Nutrient Limitation and Coral Bleaching. Bioscience 2021. [DOI: 10.1093/biosci/biab101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Coral reefs continue to experience extreme environmental pressure from climate change stressors, but many coral reefs are also exposed to eutrophication. It has been proposed that changes in the stoichiometry of ambient nutrients increase the mortality of corals, whereas eutrophication may facilitate phase shifts to macroalgae-dominated coral reefs when herbivory is low or absent. But are corals ever nutrient limited, and can eutrophication destabilize the coral symbiosis making it more sensitive to environmental stress because of climate change? The effects of eutrophication are confounded not just by the effects of climate change but by the presence of chemical pollutants in industrial, urban, and agricultural wastes. Because of these confounding effects, the increases in nutrients or changes in their stoichiometry in coastal environments, although they are important at the organismal and community level, cannot currently be disentangled from each other or from the more significant effects of climate change stressors on coral reefs.
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Affiliation(s)
- Michael P Lesser
- University of New Hampshire, Durham, New Hampshire, United States
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23
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Cheong KY, Firlar E, Ficaro L, Gorbunov MY, Kaelber JT, Falkowski PG. Saturation of thylakoid-associated fatty acids facilitates bioenergetic coupling in a marine diatom allowing for thermal acclimation. GLOBAL CHANGE BIOLOGY 2021; 27:3133-3144. [PMID: 33749034 DOI: 10.1111/gcb.15612] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/03/2021] [Indexed: 06/12/2023]
Abstract
In a rapidly warming world, we ask, "What limits the potential of marine diatoms to acclimate to elevated temperatures?," a group of ecologically successful unicellular eukaryotic photoautotrophs that evolved in a cooler ocean and are critical to marine food webs. To this end, we examined thermal tolerance mechanisms related to photosynthesis in the sequenced and transformable model diatom Phaeodactylum tricornutum. Data from transmission electron microscopy (TEM) and fatty acid methyl ester-gas chromatography mass spectrometry (FAME-GCMS) suggest that saturating thylakoid-associated fatty acids allowed rapid (on the order of hours) thermal tolerance up to 28.5°C. Beyond this critical temperature, thylakoid ultrastructure became severely perturbed. Biophysical analyses revealed that electrochemical leakage through the thylakoid membranes was extremely sensitive to elevated temperature (Q10 of 3.5). Data suggest that the loss of the proton motive force (pmf) occurred even when heat-labile photosystem II (PSII) was functioning, and saturation of thylakoid-associated fatty acids was active. Indeed, growth was inhibited when leakage of pmf through thylakoid membranes was insufficiently compensated by proton input from PSII. Our findings provide a mechanistic understanding of the importance of rapid saturation of thylakoid-associated fatty acids for ultrastructure maintenance and a generation of pmf at elevated temperatures. To the extent these experimental results apply, the ability of diatoms to generate a pmf may be a sensitive parameter for thermal sensitivity diagnosis in phytoplankton.
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Affiliation(s)
- Kuan Yu Cheong
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Emre Firlar
- Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
- Rutgers New Jersey Cryo-Electron Microscopy & Tomography Core Facility, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Lia Ficaro
- Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
- Rutgers New Jersey Cryo-Electron Microscopy & Tomography Core Facility, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Maxim Y Gorbunov
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Jason T Kaelber
- Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
- Rutgers New Jersey Cryo-Electron Microscopy & Tomography Core Facility, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Paul G Falkowski
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
- Department of Earth and Planetary Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
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24
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Blanckaert ACA, de Barros Marangoni LF, Rottier C, Grover R, Ferrier-Pagès C. Low levels of ultra-violet radiation mitigate the deleterious effects of nitrate and thermal stress on coral photosynthesis. MARINE POLLUTION BULLETIN 2021; 167:112257. [PMID: 33756374 DOI: 10.1016/j.marpolbul.2021.112257] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 03/05/2021] [Accepted: 03/07/2021] [Indexed: 05/20/2023]
Abstract
Reef ecosystems are under increasing pressure from global and local stressors. Rising seawater temperature and high ultraviolet radiation (UVR) levels are the main drivers of the disruption of the coral-dinoflagellate symbiosis (bleaching). Bleaching can also be exacerbated by nitrate contamination in coastal reefs. However, the underlying physiological mechanisms are still poorly understood. Here, we assessed the physiological and oxidative state of the scleractinian coral Pocillopora damicornis, maintained eight weeks in a crossed-factorial design including two temperatures (26 °C or 30 °C), and two nitrate (0.5 and 3 μM-enriched), and UVR (no UVR and 25/1.5 Wm-2 UVA/B) levels. Nitrate enrichment, and high temperature, significantly impaired coral photosynthesis. However, UVR alleviated the nitrate and temperature-induced decrease in photosynthesis, by increasing the coral's antioxidant capacity. The present study contributes to our understanding of the combined effects of abiotic stressors on coral bleaching susceptibility. Such information is urgently needed to refine reef management strategies.
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Affiliation(s)
- Alice C A Blanckaert
- Sorbonne Université, UPMC Université Paris VI, IFD-ED 129, Paris Cedex 05, France; Centre Scientifique de Monaco, Coral Ecophysiology team, 8 Quai Antoine 1er, MC 98000, Monaco.
| | | | - Cécile Rottier
- Centre Scientifique de Monaco, Coral Ecophysiology team, 8 Quai Antoine 1er, MC 98000, Monaco
| | - Renaud Grover
- Centre Scientifique de Monaco, Coral Ecophysiology team, 8 Quai Antoine 1er, MC 98000, Monaco
| | - Christine Ferrier-Pagès
- Centre Scientifique de Monaco, Coral Ecophysiology team, 8 Quai Antoine 1er, MC 98000, Monaco
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25
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Sikorskaya TV, Ermolenko EV, Boroda AV, Ginanova TT. Physiological processes and lipidome dynamics in the soft coral Sinularia heterospiculata under experimental bleaching. Comp Biochem Physiol B Biochem Mol Biol 2021; 255:110609. [PMID: 33957260 DOI: 10.1016/j.cbpb.2021.110609] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 04/15/2021] [Accepted: 04/26/2021] [Indexed: 11/17/2022]
Abstract
Coral polyps host intracellular symbiotic dinoflagellates (SD). The loss of SD (referred as bleaching) under stressful environmental conditions is the main reason of coral reef destruction, and therefore, intensively studied over the world. Lipids are the structural base of biomembranes and energy reserve of corals and are directly involved in the coral bleaching. In order to establish a relationship between coral tissue morphology, physiological processes and lipidome dynamics during bleaching, the soft coral Sinularia heterospiculata was exposed to experimental heat stress (33 °C) for 72 h. A chlorophyll content, structure of cells, the level of reactive oxygen species (ROS), and molecular species of storage and structural lipids were analyzed. After 24 h of heat exposure, the level of ROS-positive SD cells did not increase, but the host tissues lost a significant part of SD. The removal of SD cells by exocytosis were suggested. Exocytosis was presumed to prevail at earlier stages of the soft coral bleaching. Symbiophagosomes with degenerative SD were observed in the stressed coral host cells. After 24 h, the content of phosphatidylinositols, which involved in apoptosis and autophagy, was significantly decreased. The innate immune response was triggered, and SD were digested by the coral host. After 48 h, a degradation of SD chloroplasts and a decrease in the specific monogalactosyldiacylglycerol molecular species were detected that confirmed a disruption of lipid biosynthesis in chloroplasts. At the end of coral bleaching, the appearance of oxidized phosphatidylethanolamines, indicating damage to the host membranes, and the degradation of the coral tissues were simultaneously observed. Thus, a switch between dominant mechanisms of the SD loss during bleaching of S. heterospiculata was found and proved by certain variations of the lipidomic profile. Lipidomic parameters may become indicators of physiological processes occurring in the symbiotic coral organism and may be used for assessing anthropogenic or natural destructive effects on coral reefs.
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Affiliation(s)
- Tatyana V Sikorskaya
- A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russian Federation.
| | - Ekaterina V Ermolenko
- A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russian Federation
| | - Andrey V Boroda
- A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russian Federation
| | - Taliya T Ginanova
- A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russian Federation
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26
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Alderdice R, Suggett DJ, Cárdenas A, Hughes DJ, Kühl M, Pernice M, Voolstra CR. Divergent expression of hypoxia response systems under deoxygenation in reef-forming corals aligns with bleaching susceptibility. GLOBAL CHANGE BIOLOGY 2021; 27:312-326. [PMID: 33197302 DOI: 10.1111/gcb.15436] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/27/2020] [Indexed: 06/11/2023]
Abstract
Exposure of marine life to low oxygen is accelerating worldwide via climate change and localized pollution. Mass coral bleaching and mortality have recently occurred where reefs have experienced chronic low oxygen events. However, the mechanistic basis of tolerance to oxygen levels inadequate to sustain normal functioning (i.e. hypoxia) and whether it contributes to bleaching susceptibility, remain unknown. We therefore experimentally exposed colonies of the environmentally resilient Acropora tenuis, a common reef-building coral from the Great Barrier Reef, to deoxygenation-reoxygenation stress that was aligned to their natural night-day light cycle. Specifically, the treatment involved removing the 'night-time O2 buffer' to challenge the inherent hypoxia thresholds. RNA-Seq analysis revealed that coral possess a complete and active hypoxia-inducible factor (HIF)-mediated hypoxia response system (HRS) homologous to other metazoans. As expected, A. tenuis exhibited bleaching resistance and showed a strong inducibility of HIF target genes in response to deoxygenation stress. We applied this same approach in parallel to a colony of Acropora selago, known to be environmnetally susceptible, which conversely exhibited a bleaching phenotype response. This phenotypic divergence of A. selago was accompanied by contrasting gene expression profiles indicative of varied effectiveness of their HIF-HRS. Based on our RNA-Seq analysis, we propose (a) that the HIF-HRS is central for corals to manage deoxygenation stress and (b) that key genes of this system (and the wider gene network) may contribute to variation in coral bleaching susceptibility. Our analysis suggests that heat shock protein (hsp) 70 and 90 are important for low oxygen stress tolerance and further highlights how hsp90 expression might also affect the inducibility of coral HIF-HRS in overcoming a metabolic crisis under deoxygenation stress. We propose that differences in coral HIF-HRS could be central in regulating sensitivity to other climate change stressors-notably thermal stress-that commonly drive bleaching.
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Affiliation(s)
- Rachel Alderdice
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - David J Suggett
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Anny Cárdenas
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - David J Hughes
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Michael Kühl
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
- Marine Biology Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Mathieu Pernice
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
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27
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Campos P, Pires A, Figueira E. Can Palythoa cf. variabilis biochemical patterns be used to predict coral reef conservation state in Todos Os Santos Bay? ENVIRONMENTAL RESEARCH 2020; 186:109504. [PMID: 32334169 DOI: 10.1016/j.envres.2020.109504] [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: 01/06/2020] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 06/11/2023]
Abstract
Coral reefs are one of the most diverse, complex and productive marine ecosystems on the planet. Global climate change and other anthropogenic impacts have had a strong impact on the equilibrium of these ecosystems and causing the denominated "coral reef crisis". One consequence of coral reef crisis is the phase shift in reef communities, where scleractinian corals responsible for the bioconstruction of the coralline building are replaced by macroalgae or soft corals. In Todos os Santos Bay (TSB) there is a rare case of phase shift caused by the soft coral Palythoa cf. variabilis. When in population outbreak, this coral species becomes dominant and leads to loss of scleractinian coral cover. Palythoa genus establishes a symbiotic relationship with dinoflagellate algae of the genus Symbiodinium, that is changed in phase shift coral reefs, but other alterations remain unknown. In this study, the metabolism (oxidative damage, antioxidant and biotransformation enzymes, electron transport chain activity and photosynthetic pigments) of P. cf. variabilis from reefs in different conservation states was studied to identify and relate if changes that may occur in the biochemical and metabolism of the coral might trigger the population outbreak, identify parameters recognizing if corals are in stress and assess if one or more parameters can reflect the level of stress organisms are experiencing. The results obtained evidenced a clear distinction in the biochemistry and metabolism of corals from conserved sites and sites in phase shift, and these changes may be the trigger for population outbreak. Some of the parameters were able to discriminate the level of stress corals are experiencing and may allow to recognize the most at-risk coral reefs that need immediate intervention and prevent the entry into or revert P. cf. variabilis outbreak and phase shift in coral reefs. Actions like these can be of vital importance for the preservation of TSB coral reefs and possibly for other threatened reefs worldwide.
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Affiliation(s)
- Priscilla Campos
- Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal; Universidade Federal de Sergipe, 49100-000, Brazil
| | - Adília Pires
- Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
| | - Etelvina Figueira
- Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal
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28
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Rosic N, Rémond C, Mello-Athayde MA. Differential impact of heat stress on reef-building corals under different light conditions. MARINE ENVIRONMENTAL RESEARCH 2020; 158:104947. [PMID: 32250839 DOI: 10.1016/j.marenvres.2020.104947] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 03/02/2020] [Accepted: 03/07/2020] [Indexed: 06/11/2023]
Abstract
Heat stress is an environmental factor that regularly challenges the well-being of living organisms. This study aims to examine the physiological changes happening in two reef-building coral species exposed to thermal stress under various light conditions. The two ecologically relevant heatwave scenarios were applied under ambient lights (high irradiance) and reduced light conditions (250 and < 10 μmol photons m-2 s-1). Corals were exposed to elevated temperatures of 32°C (plus 6°) for a period of 1 up to 5 days corresponding to heatwaves reported on the Great Barrier Reef (GBR) that were associated with coral bleaching. We monitored changes in the physiological performance of these two coral species by measuring symbionts and corals' physiological parameters including symbiont density, levels of multiple algal pigments (chlorophyll a and peridinin), as well as the changes in the host protein concentration. During the short-term heat stress, both species were with stable physiological performance with the only exception of Stylophora pistillata under ambient lights. These results show that S. pistillata was negatively influenced by a synergistic effect of temperature and high irradiance resulting in the first signs of bleaching after only 24h of thermal stress. Exposure to prolonged thermal stress, characterised with a slower rate of temperature increase, affected both coral species investigated and resulted in bleaching mainly by day 5. Interestingly, severe light reduction (<10 μmol photons m-2 s-1) made Acropora millepora corals more thermally sensitive and resulted in earlier signs of bleaching (on day 3). These findings indicate that there was a synergistic effect of very low lights and thermal stress that caused higher levels of bleaching in A. millepora. Our results revealed differential thermal sensitivity for two branching corals exposed to different thermal stress scenarios under various light irradiance conditions, naturally found in their existing habitats. Consequently, global warming may have a differential impact on coral reef biodiversity depending on light availability.
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Affiliation(s)
- Nedeljka Rosic
- School of Health and Human Sciences, Southern Cross University, Gold Coast, QLD, 4225, Australia; Marine Ecology Research Centre, Southern Cross University, Lismore, NSW, 2480, Australia.
| | | | - Matheus A Mello-Athayde
- School of Biological Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia
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29
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Tandon K, Lu CY, Chiang PW, Wada N, Yang SH, Chan YF, Chen PY, Chang HY, Chiou YJ, Chou MS, Chen WM, Tang SL. Comparative genomics: Dominant coral-bacterium Endozoicomonas acroporae metabolizes dimethylsulfoniopropionate (DMSP). THE ISME JOURNAL 2020; 14:1290-1303. [PMID: 32055028 PMCID: PMC7174347 DOI: 10.1038/s41396-020-0610-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 01/30/2020] [Accepted: 02/04/2020] [Indexed: 01/24/2023]
Abstract
Dominant coral-associated Endozoicomonas bacteria species are hypothesized to play a role in the coral sulfur cycle by metabolizing dimethylsulfoniopropionate (DMSP) into dimethylsulfide (DMS); however, no sequenced genome to date harbors genes for this process. In this study, we assembled high-quality (>95% complete) draft genomes of strains of the recently added species Endozoicomonas acroporae (Acr-14T, Acr-1, and Acr-5) isolated from the coral Acropora sp. and performed a comparative genomic analysis on the genus Endozoicomonas. We identified DMSP CoA-transferase/lyase-a dddD gene homolog in all sequenced genomes of E. acroporae strains-and functionally characterized bacteria capable of metabolizing DMSP into DMS via the DddD cleavage pathway using RT-qPCR and gas chromatography (GC). Furthermore, we demonstrated that E. acroporae strains can use DMSP as a carbon source and have genes arranged in an operon-like manner to link DMSP metabolism to the central carbon cycle. This study confirms the role of Endozoicomonas in the coral sulfur cycle.
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Affiliation(s)
- Kshitij Tandon
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
- Bioinformatics Program, Institute of Information Science, Taiwan International Graduate Program, Academia Sinica, Taipei, 115, Taiwan
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, 300, Taiwan
| | - Chih-Ying Lu
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Pei-Wen Chiang
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Naohisa Wada
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Shan-Hua Yang
- Institute of Fisheries Science, National Taiwan University, Taipei, 10617, Taiwan
| | - Ya-Fan Chan
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Ping-Yun Chen
- Institute of Environmental Engineering, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan
| | - Hsiao-Yu Chang
- Institute of Environmental Engineering, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan
| | - Yu-Jing Chiou
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan
- Institute of Oceanography, National Taiwan University, Taipei, 10617, Taiwan
| | - Ming-Shean Chou
- Institute of Environmental Engineering, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan
| | - Wen-Ming Chen
- Laboratory of Microbiology, Department of Seafood Science, National Kaohsiung Marine University, No. 142, Hai-Chuan Rd, Nan-Tzu, Kaohsiung City, 811, Taiwan
| | - Sen-Lin Tang
- Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan.
- Bioinformatics Program, Institute of Information Science, Taiwan International Graduate Program, Academia Sinica, Taipei, 115, Taiwan.
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30
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Suggett DJ, Smith DJ. Coral bleaching patterns are the outcome of complex biological and environmental networking. GLOBAL CHANGE BIOLOGY 2020; 26:68-79. [PMID: 31618499 DOI: 10.1111/gcb.14871] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 09/20/2019] [Indexed: 05/26/2023]
Abstract
Continued declines in coral reef health over the past three decades have been punctuated by severe mass coral bleaching-induced mortality events that have grown in intensity and frequency under climate change. Intensive global research efforts have therefore persistently focused on bleaching phenomena to understand where corals bleach, when and why-resulting in a large-yet still somewhat patchy-knowledge base. Particularly catastrophic bleaching-induced coral mortality events in the past 5 years have catalyzed calls for a more diverse set of reef management tools, extending far beyond climate mitigation and reef protection, to also include more aggressive interventions. However, the effectiveness of these various tools now rests on rapidly assimilating our knowledge base of coral bleaching into more integrated frameworks. Here, we consider how the past three decades of intensive coral bleaching research has established the basis for complex biological and environmental networks, which together regulate outcomes of bleaching severity. We discuss how we now have enough scaffold for conceptual biological and environmental frameworks underpinning bleaching susceptibility, but that new tools are urgently required to translate this to an operational system informing-and testing-bleaching outcomes. Specifically, adopting network models that can fully describe and predict metabolic functioning of coral holobionts, and how this functioning is regulated by complex doses and interactions among environmental factors. Identifying knowledge gaps limiting operation of such models is the logical step to immediately guide and prioritize future experiments and observations. We are at a time-critical point where we can implement new capacity to resolve how coral bleaching patterns emerge from complex biological-environmental networks, and so more effectively inform rapidly evolving ecological management and social adaptation frameworks aimed at securing the future of coral reefs.
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Affiliation(s)
- David J Suggett
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, Australia
| | - David J Smith
- Coral Reef Research Unit, School of Biological Sciences, University of Essex, Colchester, UK
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31
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Intraspecific Diversity in the Cold Stress Response of Transposable Elements in the Diatom Leptocylindrus aporus. Genes (Basel) 2019; 11:genes11010009. [PMID: 31861932 PMCID: PMC7017206 DOI: 10.3390/genes11010009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 12/19/2019] [Indexed: 01/18/2023] Open
Abstract
Transposable elements (TEs), activated as a response to unfavorable conditions, have been proposed to contribute to the generation of genetic and phenotypic diversity in diatoms. Here we explore the transcriptome of three warm water strains of the diatom Leptocylindrus aporus, and the possible involvement of TEs in their response to changing temperature conditions. At low temperature (13 °C) several stress response proteins were overexpressed, confirming low temperature to be unfavorable for L. aporus, while TE-related transcripts of the LTR retrotransposon superfamily were the most enriched transcripts. Their expression levels, as well as most of the stress-related proteins, were found to vary significantly among strains, and even within the same strains analysed at different times. The lack of overexpression after many months of culturing suggests a possible role of physiological plasticity in response to growth under controlled laboratory conditions. While further investigation on the possible central role of TEs in the diatom stress response is warranted, the strain-specific responses and possible role of in-culture evolution draw attention to the interplay between the high intraspecific variability and the physiological plasticity of diatoms, which can both contribute to the adaptation of a species to a wide range of conditions in the marine environment.
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32
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Measuring light scattering and absorption in corals with Inverse Spectroscopic Optical Coherence Tomography (ISOCT): a new tool for non-invasive monitoring. Sci Rep 2019; 9:14148. [PMID: 31578438 PMCID: PMC6775107 DOI: 10.1038/s41598-019-50658-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 09/17/2019] [Indexed: 12/12/2022] Open
Abstract
The success of reef-building corals for >200 million years has been dependent on the mutualistic interaction between the coral host and its photosynthetic endosymbiont dinoflagellates (family Symbiodiniaceae) that supply the coral host with nutrients and energy for growth and calcification. While multiple light scattering in coral tissue and skeleton significantly enhance the light microenvironment for Symbiodiniaceae, the mechanisms of light propagation in tissue and skeleton remain largely unknown due to a lack of technologies to measure the intrinsic optical properties of both compartments in live corals. Here we introduce ISOCT (inverse spectroscopic optical coherence tomography), a non-invasive approach to measure optical properties and three-dimensional morphology of living corals at micron- and nano-length scales, respectively, which are involved in the control of light propagation. ISOCT enables measurements of optical properties in the visible range and thus allows for characterization of the density of light harvesting pigments in coral. We used ISOCT to characterize the optical scattering coefficient (μs) of the coral skeleton and chlorophyll a concentration of live coral tissue. ISOCT further characterized the overall micro- and nano-morphology of live tissue by measuring differences in the sub-micron spatial mass density distribution (D) that vary throughout the tissue and skeleton and give rise to light scattering, and this enabled estimates of the spatial directionality of light scattering, i.e., the anisotropy coefficient, g. Thus, ISOCT enables imaging of coral nanoscale structures and allows for quantifying light scattering and pigment absorption in live corals. ISOCT could thus be developed into an important tool for rapid, non-invasive monitoring of coral health, growth and photophysiology with unprecedented spatial resolution.
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33
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Tamir R, Eyal G, Kramer N, Laverick JH, Loya Y. Light environment drives the shallow‐to‐mesophotic coral community transition. Ecosphere 2019. [DOI: 10.1002/ecs2.2839] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Affiliation(s)
- Raz Tamir
- School of Zoology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
- The Interuniversity Institute for Marine Sciences in Eilat Eilat Israel
| | - Gal Eyal
- ARC Centre of Excellence for Coral Reef Studies School of Biological Sciences The University of Queensland St. Lucia Queensland 4072 Australia
- The Mina & Everard Goodman Faculty of Life Sciences Bar Ilan University Ramat Gan Israel
| | - Netanel Kramer
- School of Zoology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
| | - Jack H. Laverick
- Department of Zoology University of Oxford South Parks Road Oxford OX1 3PS UK
| | - Yossi Loya
- School of Zoology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
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34
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Hernández-Elizárraga VH, Olguín-López N, Hernández-Matehuala R, Ocharán-Mercado A, Cruz-Hernández A, Guevara-González RG, Caballero-Pérez J, Ibarra-Alvarado C, Sánchez-Rodríguez J, Rojas-Molina A. Comparative Analysis of the Soluble Proteome and the Cytolytic Activity of Unbleached and Bleached Millepora complanata ("Fire Coral") from the Mexican Caribbean. Mar Drugs 2019; 17:md17070393. [PMID: 31277227 PMCID: PMC6669453 DOI: 10.3390/md17070393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 01/24/2023] Open
Abstract
Coral bleaching caused by global warming has resulted in massive damage to coral reefs worldwide. Studies addressing the consequences of elevated temperature have focused on organisms of the class Anthozoa, and up to now, there is little information regarding the mechanisms by which reef forming Hydrozoans face thermal stress. In this study, we carried out a comparative analysis of the soluble proteome and the cytolytic activity of unbleached and bleached Millepora complanata ("fire coral") that inhabited reef colonies exposed to the 2015-2016 El Niño-Southern Oscillation in the Mexican Caribbean. A differential proteomic response involving proteins implicated in key cellular processes, such as glycolysis, DNA repair, stress response, calcium homeostasis, exocytosis, and cytoskeleton organization was found in bleached hydrocorals. Four of the proteins, whose levels increased in bleached specimens, displayed sequence similarity to a phospholipase A2, an astacin-like metalloprotease, and two pore forming toxins. However, a protein, which displayed sequence similarity to a calcium-independent phospholipase A2, showed lower levels in bleached cnidarians. Accordingly, the hemolytic effect of the soluble proteome of bleached hydrocorals was significantly higher, whereas the phospholipase A2 activity was significantly reduced. Our results suggest that bleached M. complanata is capable of increasing its toxins production in order to balance the lack of nutrients supplied by its symbionts.
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Affiliation(s)
- Víctor Hugo Hernández-Elizárraga
- Posgrado en Ciencias Químico Biológicas, Facultad de Química, Universidad Autónoma de Querétaro, Cerro de las Campanas S/N, C.P. 76010 Querétaro, Querétaro, México
| | - Norma Olguín-López
- Posgrado en Ciencias Químico Biológicas, Facultad de Química, Universidad Autónoma de Querétaro, Cerro de las Campanas S/N, C.P. 76010 Querétaro, Querétaro, México
| | - Rosalina Hernández-Matehuala
- Posgrado en Ciencias Químico Biológicas, Facultad de Química, Universidad Autónoma de Querétaro, Cerro de las Campanas S/N, C.P. 76010 Querétaro, Querétaro, México
| | - Andrea Ocharán-Mercado
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, Cerro de las Campanas S/N, C.P. 76010 Querétaro, Querétaro, México
| | - Andrés Cruz-Hernández
- Laboratorio de Biología Molecular. Escuela de Agronomía, Universidad de La Salle Bajío, Av. Universidad 15 602, Colonia Lomas del Campestre, C.P. 37150 León, Guanajuato, México
| | - Ramón Gerardo Guevara-González
- C.A Ingeniería de Biosistemas, Facultad de Ingeniería-Campus Amazcala, Universidad Autónoma de Querétaro, Carr. Chichimequillas-Amazcala Km. 1, S/N, C.P. 76265 Amazcala, El Marqués, Querétaro, México
| | - Juan Caballero-Pérez
- Facultad de Química, Universidad Autónoma de Querétaro, Cerro de las Campanas S/N, C.P. 76010 Querétaro, Querétaro, México
| | - César Ibarra-Alvarado
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, Cerro de las Campanas S/N, C.P. 76010 Querétaro, Querétaro, México
| | - Judith Sánchez-Rodríguez
- Unidad Académica de Sistemas Arrecifales Puerto Morelos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Prolongación Niños Héroes S/N, Puerto Morelos, C.P. 77580 Quintana Roo, México
| | - Alejandra Rojas-Molina
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, Cerro de las Campanas S/N, C.P. 76010 Querétaro, Querétaro, México.
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Lopes AR, Faleiro F, Rosa IC, Pimentel MS, Trubenbach K, Repolho T, Diniz M, Rosa R. Physiological resilience of a temperate soft coral to ocean warming and acidification. Cell Stress Chaperones 2018; 23:1093-1100. [PMID: 29948929 PMCID: PMC6111073 DOI: 10.1007/s12192-018-0919-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 04/22/2018] [Accepted: 05/21/2018] [Indexed: 01/04/2023] Open
Abstract
Atmospheric concentration of carbon dioxide (CO2) is increasing at an unprecedented rate and subsequently leading to ocean acidification. Concomitantly, ocean warming is intensifying, leading to serious and predictable biological impairments over marine biota. Reef-building corals have proven to be very vulnerable to climate change, but little is known about the resilience of non-reef-building species. In this study, we investigated the effects of ocean warming and acidification on the antioxidant enzyme activity (CAT-catalase, and GST-glutathione S-transferase), lipid peroxidation (using malondialdehyde, MDA-levels as a biomarker) and heat shock response (HSP70/HSC70 content) of the octocoral Veretillum cynomorium. After 60 days of acclimation, no mortalities were registered in all treatments. Moreover, CAT and GST activities, as well as MDA levels, did not change significantly under warming and/or acidification. Heat shock response was significantly enhanced under warming, but high CO2 did not have a significant effect. Contrasting to many of their tropical coral-reef relatives, our findings suggest that temperate shallow-living octocorals may be able to physiologically withstand future conditions of increased temperature and acidification.
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Affiliation(s)
- Ana Rita Lopes
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Laboratório Marítimo da Guia, Avenida Nossa Senhora do Cabo 939, 2750-374, Cascais, Portugal.
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Quinta da Torre, 2829-516, Caparica, Portugal.
| | - Filipa Faleiro
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Laboratório Marítimo da Guia, Avenida Nossa Senhora do Cabo 939, 2750-374, Cascais, Portugal
| | - Inês C Rosa
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Laboratório Marítimo da Guia, Avenida Nossa Senhora do Cabo 939, 2750-374, Cascais, Portugal
| | - Marta S Pimentel
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Laboratório Marítimo da Guia, Avenida Nossa Senhora do Cabo 939, 2750-374, Cascais, Portugal
| | - Katja Trubenbach
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Laboratório Marítimo da Guia, Avenida Nossa Senhora do Cabo 939, 2750-374, Cascais, Portugal
| | - Tiago Repolho
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Laboratório Marítimo da Guia, Avenida Nossa Senhora do Cabo 939, 2750-374, Cascais, Portugal
| | - Mário Diniz
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Quinta da Torre, 2829-516, Caparica, Portugal
| | - Rui Rosa
- MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências da Universidade de Lisboa, Laboratório Marítimo da Guia, Avenida Nossa Senhora do Cabo 939, 2750-374, Cascais, Portugal
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Ventura P, Toullec G, Fricano C, Chapron L, Meunier V, Röttinger E, Furla P, Barnay-Verdier S. Cnidarian Primary Cell Culture as a Tool to Investigate the Effect of Thermal Stress at Cellular Level. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2018; 20:144-154. [PMID: 29313151 DOI: 10.1007/s10126-017-9791-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 12/14/2017] [Indexed: 06/07/2023]
Abstract
In the context of global change, symbiotic cnidarians are largely affected by seawater temperature elevation leading to symbiosis breakdown. This process, also called bleaching, is triggered by the dysfunction of the symbiont photosystems causing an oxidative stress and cell death to both symbiont and host cells. In our study, we wanted to elucidate the intrinsic capacity of isolated animal cells to deal with thermal stress in the absence of symbiont. In that aim, we have characterized an animal primary cell culture form regenerating tentacles of the temperate sea anemone Anemonia viridis. We first compared the potential of whole tissue tentacle or separated epidermal or gastrodermal monolayers as tissue sources to settle animal cell cultures. Interestingly, only isolated cells extracted from whole tentacles allowed establishing a viable and proliferative primary cell culture throughout 31 days. The analysis of the expression of tissue-specific and pluripotency markers defined cultivated cells as differentiated cells with gastrodermal origin. The characterization of the animal primary cell culture allowed us to submit the obtained gastrodermal cells to hyperthermal stress (+ 5 and + 8 °C) during 1 and 7 days. Though cell viability was not affected at both hyperthermal stress conditions, cell growth drastically decreased. In addition, only a + 8 °C hyperthermia induced a transient increase of antioxidant defences at 1 day but no ubiquitin or carbonylation protein damages. These results demonstrated an intrinsic resistance of cnidarian gastrodermal cells to hyperthermal stress and then confirmed the role of symbionts in the hyperthermia sensitivity leading to bleaching.
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Affiliation(s)
- P Ventura
- Sorbonne Universités, UPMC Université Paris 06, Université Antilles, Université Nice Sophia Antipolis, CNRS, Laboratoire Evolution Paris Seine, Institut de Biologie Paris Seine (EPS-IBPS), Paris, France
| | - G Toullec
- Sorbonne Universités, UPMC Université Paris 06, Université Antilles, Université Nice Sophia Antipolis, CNRS, Laboratoire Evolution Paris Seine, Institut de Biologie Paris Seine (EPS-IBPS), Paris, France
| | - C Fricano
- Sorbonne Universités, UPMC Université Paris 06, Université Antilles, Université Nice Sophia Antipolis, CNRS, Laboratoire Evolution Paris Seine, Institut de Biologie Paris Seine (EPS-IBPS), Paris, France
| | - L Chapron
- Sorbonne Universités, UPMC Université Paris 06, Université Antilles, Université Nice Sophia Antipolis, CNRS, Laboratoire Evolution Paris Seine, Institut de Biologie Paris Seine (EPS-IBPS), Paris, France
- Sorbonne Universités, UPMC Université Paris 06, CNRS, Laboratoire d'Ecogéochimie des Environnements Benthiques (LECOB, Observatoire Océanologique, Banyuls/Mer, France
| | - V Meunier
- Sorbonne Universités, UPMC Université Paris 06, Université Antilles, Université Nice Sophia Antipolis, CNRS, Laboratoire Evolution Paris Seine, Institut de Biologie Paris Seine (EPS-IBPS), Paris, France
| | - E Röttinger
- CNRS, INSERM, Institute for Research on Cancer and Aging (IRCAN), Université Côte d'Azur, Nice, France
| | - P Furla
- Sorbonne Universités, UPMC Université Paris 06, Université Antilles, Université Nice Sophia Antipolis, CNRS, Laboratoire Evolution Paris Seine, Institut de Biologie Paris Seine (EPS-IBPS), Paris, France
| | - S Barnay-Verdier
- Sorbonne Universités, UPMC Université Paris 06, Université Antilles, Université Nice Sophia Antipolis, CNRS, Laboratoire Evolution Paris Seine, Institut de Biologie Paris Seine (EPS-IBPS), Paris, France.
- UMR 7138 "Evolution Paris Seine", Symbiose Marine Team, Paris, France.
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37
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Wietheger A, Starzak DE, Gould KS, Davy SK. Differential ROS Generation in Response to Stress in Symbiodinium spp. THE BIOLOGICAL BULLETIN 2018; 234:11-21. [PMID: 29694799 DOI: 10.1086/696977] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Oxidative stress inside cells occurs when the production of reactive oxygen species (ROS) is no longer efficiently counterbalanced by the generation of antioxidants. In this study, we measured the intracellular production of ROS, including hydrogen peroxide (H2O2), superoxide (O2-), and singlet oxygen (1O2), in cultured dinoflagellates of the genus Symbiodinium under thermal and oxidative stress. ROS tagged with fluorescent probes were measured by flow cytometry. Dissimilar Symbiodinium internal transcribed spacer 2 (ITS2) clades or phylotypes (A1, B2, E, F1) produced ROS in different quantities in response to stress. For example, when comparing the control (26 °C) to the high-temperature treatment (35 °C), Symbiodinium E showed no change in the intracellular concentrations of any of the ROS; but phylotype A1 displayed a 10-fold increase in the overall ROS concentration and a 4-fold increase in O2-. Under oxidative stress, when 8 mmol l-1 H2O2 was added to the cells, these same two Symbiodinium phylotypes increased their overall concentrations of ROS, but only Symbiodinium E showed an increase in the concentrations of O2- (2×) and 1O2 (3×). Therefore, not only were the stress responses of the various Symbiodinium phylotypes different but also the responses of individual phylotypes to thermal and oxidative stress were different in terms of ROS production. Variation in the quality and quantity of ROS generation and its implications for subsequent antioxidant production suggest that different stress mechanisms are at play. While our experiments were done under laboratory conditions that did not necessarily mirror ecological ones, these results provide new insight into processes inside Symbiodinium cells during stress events and add new explanations for a phylotype's susceptibility to stress.
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Key Words
- 1O2, singlet oxygen
- APX, ascorbate peroxidase
- CAT, catalase
- DMSO, dimethyl sulfoxide
- H2DCF-DA, 2′,7′-dichlorodihydrofluorescein diacetate
- ITS2, internal transcribed spacer 2
- NPQ, non-photochemical quenching
- O2−, superoxide
- OEC, oxygen-evolving complex
- OH•, hydroxyl radical
- PSI/II, photosystem I/II
- ROS, reactive oxygen species
- SOD, superoxide dismutase
- SOG, singlet oxygen sensor green
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39
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Cunning R, Muller EB, Gates RD, Nisbet RM. A dynamic bioenergetic model for coral- Symbiodinium symbioses and coral bleaching as an alternate stable state. J Theor Biol 2017; 431:49-62. [DOI: 10.1016/j.jtbi.2017.08.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 07/14/2017] [Accepted: 08/02/2017] [Indexed: 11/26/2022]
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Macrander JC, Dimond JL, Bingham BL, Reitzel AM. Transcriptome sequencing and characterization of Symbiodinium muscatinei and Elliptochloris marina, symbionts found within the aggregating sea anemone Anthopleura elegantissima. Mar Genomics 2017; 37:82-91. [PMID: 28888836 DOI: 10.1016/j.margen.2017.08.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 08/26/2017] [Accepted: 08/27/2017] [Indexed: 12/20/2022]
Abstract
There is a growing body of literature using transcriptomic data to study how tropical cnidarians and their photosynthetic endosymbionts respond to environmental stressors and participate in metabolic exchange. Despite these efforts, our understanding of how essential genes function to facilitate symbiosis establishment and maintenance remains limited. The inclusion of taxonomically and ecologically diverse endosymbionts will enhance our understanding of these interactions. Here we characterize the transcriptomes of two very different symbionts found within the temperate sea anemone Anthopleura elegantissima: the chlorophyte Elliptochloris marina and the dinoflagellate Symbiodinium muscatinei. We use a multi-level approach to assess the diversity of genes found across S. muscatinei and E. marina transcriptomes, and compare their overall protein domains with other dinoflagellates and chlorophytes. Our analysis identified several genes that are potentially involved in mitigating stress response (e.g., heat shock proteins pathways for mediating reactive oxygen species) and metabolic exchange (e.g., ion transporters). Finally, we show that S. muscatinei and other Symbiodinium strains are equipped with a high salt peridinin-chl-protein (HSPCP) gene previously identified only in free-living dinoflagellates. The addition of these transcriptomes to the cnidarian-symbiont molecular toolkit will aid in understanding how these vitally important symbiotic relationships are established and maintained across a variety of environmental conditions.
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Affiliation(s)
- Jason C Macrander
- Department of Biological Sciences, University of North Carolina, Charlotte, 9201 University City Blvd, Charlotte, NC 28223, USA.
| | - James L Dimond
- Shannon Point Marine Center, Western Washington University, 1900 Shannon Point Road, Anacortes, WA 98221, USA
| | - Brian L Bingham
- Shannon Point Marine Center, Western Washington University, 1900 Shannon Point Road, Anacortes, WA 98221, USA; Department of Environmental Sciences, Western Washington University, 516 High Street, Bellingham, WA 98225, USA
| | - Adam M Reitzel
- Department of Biological Sciences, University of North Carolina, Charlotte, 9201 University City Blvd, Charlotte, NC 28223, USA
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Marangoni LFDB, Marques JA, Duarte GAS, Pereira CM, Calderon EN, Castro CBE, Bianchini A. Copper effects on biomarkers associated with photosynthesis, oxidative status and calcification in the Brazilian coral Mussismilia harttii (Scleractinia, Mussidae). MARINE ENVIRONMENTAL RESEARCH 2017; 130:248-257. [PMID: 28823595 DOI: 10.1016/j.marenvres.2017.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 08/07/2017] [Accepted: 08/08/2017] [Indexed: 06/07/2023]
Abstract
Seawater contamination with metals, such as copper (Cu), is a notable local impact threatening coral reefs. Cu effects on biomarkers associated with photosynthesis, oxidative status and calcification were evaluated in the Brazilian coral Mussismilia harttii using a marine mesocosm facility. Polyps were kept under control conditions (1.9 μg L-1 Cu) or exposed to dissolved Cu (3.0, 4.8, and 6.7 μg L-1) for 12 days. Photochemical efficiency of the photosystem II of symbiotic algae (zooxanthellae) was measured and polyps were analyzed for antioxidant capacity, lipid peroxidation, DNA damage, and carbonic anhydrase Ca-ATPase, Mg-ATPase and (Ca,Mg)-ATPase activities after 12 days. Results highlighted the effects of Cu exposure, leading corals to an oxidative stress condition [increased total antioxidant capacity (TAC) and DNA damage] and a possible reduced calcification ability [decreased (Ca,Mg)-ATPase activity]. Therefore, biomarkers associated with oxidative status (TAC and DNA damage) and calcification [(Ca, Mg)-ATPase] are indicated as good predictors of corals health.
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Affiliation(s)
- Laura Fernandes de Barros Marangoni
- Programa de Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande, Av. Itália, km 8, Rio Grande, RS 96203-900, Brazil.
| | - Joseane Aparecida Marques
- Programa de Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande, Av. Itália, km 8, Rio Grande, RS 96203-900, Brazil.
| | - Gustavo Adolpho Santos Duarte
- Programa de Pós-graduação em Zoologia, Museu Nacional, Universidade Federal do Rio de Janeiro, Parque Quinta da Boa Vista, São Cristovão, Rio de Janeiro, RJ 20940-040, Brazil.
| | - Cristiano Macedo Pereira
- Programa de Pós-graduação em Zoologia, Museu Nacional, Universidade Federal do Rio de Janeiro, Parque Quinta da Boa Vista, São Cristovão, Rio de Janeiro, RJ 20940-040, Brazil; Instituto Coral Vivo, Rua dos Coqueiros, Parque Yaya, Santa Cruz Cabrália, BA 45.807-000, Brazil.
| | - Emiliano Nicolas Calderon
- Instituto Coral Vivo, Rua dos Coqueiros, Parque Yaya, Santa Cruz Cabrália, BA 45.807-000, Brazil; Museu Nacional, Universidade Federal do Rio de Janeiro, Parque Quinta da Boa Vista, São Cristovão, Rio de Janeiro, RJ 20940-040, Brazil; Programa de Pós-Graduação em Ciências Ambientais e Conservação, Núcleo em Ecologia e Desenvolvimento Socioambiental de Macaé, Universidade Federal do Rio de Janeiro (NUPEM/UFRJ), Av. São José do Barreto, 764, 27965-045 Macaé, RJ, Brazil.
| | - Clovis Barreira E Castro
- Instituto Coral Vivo, Rua dos Coqueiros, Parque Yaya, Santa Cruz Cabrália, BA 45.807-000, Brazil; Museu Nacional, Universidade Federal do Rio de Janeiro, Parque Quinta da Boa Vista, São Cristovão, Rio de Janeiro, RJ 20940-040, Brazil.
| | - Adalto Bianchini
- Programa de Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande, Av. Itália, km 8, Rio Grande, RS 96203-900, Brazil; Instituto Coral Vivo, Rua dos Coqueiros, Parque Yaya, Santa Cruz Cabrália, BA 45.807-000, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Av. Itália, km 8, Rio Grande, RS 96203-900, Brazil.
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Ou G, Wang H, Si R, Guan W. The dinoflagellate Akashiwo sanguinea will benefit from future climate change: The interactive effects of ocean acidification, warming and high irradiance on photophysiology and hemolytic activity. HARMFUL ALGAE 2017; 68:118-127. [PMID: 28962974 DOI: 10.1016/j.hal.2017.08.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 07/07/2017] [Accepted: 08/02/2017] [Indexed: 06/07/2023]
Abstract
Due to global climate change, marine phytoplankton will likely experience low pH (ocean acidification), high temperatures and high irradiance in the future. Here, this work report the results of a batch culture experiment conducted to study the interactive effects of elevated CO2, increased temperature and high irradiance on the harmful dinoflagellate Akashiwo sanguinea, isolated at Dongtou Island, Eastern China Sea. The A. sanguinea cells were acclimated in high CO2 condition for about three months before testing the responses of cells to a full factorial matrix experimentation during a 7-day period. This study measured the variation in physiological parameters and hemolytic activity in 8 treatments, representing full factorial combinations of 2 levels each of exposure to CO2 (400 and 1000μatm), temperature (20 and 28°C) and irradiance (50 and 200μmol photons m-2s-1). Sustained growth of A. sanguinea occurred in all treatments, but high CO2 (HC) stimulated faster growth than low CO2 (LC). The pigments (chlorophyll a and carotenoid) decreased in all HC treatments. The quantum yield (Fv/Fm) declined slightly in all high-temperature (HT) treatments. High irradiance (HL) induced the accumulation of ultraviolet-absorbing compounds (UVabc) irrespective of temperature and CO2. The hemolytic activity in the LC treatments, however, declined when exposed to HT and HL, but HC alleviated the adverse effects of HT and HL on hemolytic activity. All HC and HL conditions and the combinations of high temperature*high light (HTHL) and high CO2*high temperature*high light (HCHTHL) positively affected the growth in comparison to the low CO2*low temperature*low light (LCLTLL) treatment. High temperature (HT), high light (HL) and a combination of HT*HL, however, negatively impacted hemolytic activity. CO2 was the main factor that affected the growth and hemolytic activity. There were no significant interactive effects of CO2*temperature*irradiance on growth, pigment, Fv/Fm or hemolytic activity, but there were effects on Pm, α, and Ek. If these results are extrapolated to the natural environment, it can be hypothesized that A. sanguinea cells will benefit from the combination of ocean acidification, warming, and high irradiance that are likely to occur under future climate change. It is assumed that faster growth and higher hemolytic activity and UVabc of this species will occur under future conditions compared with those the current CO2 (400μatm) and temperature (20°C) conditions.
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Affiliation(s)
- Guanyong Ou
- Department of Marine Biotechnology, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Hong Wang
- Department of Marine Biotechnology, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Ranran Si
- Department of Marine Biotechnology, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Wanchun Guan
- Department of Marine Biotechnology, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
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Gajigan AP, Diaz LA, Conaco C. Resilience of the prokaryotic microbial community of Acropora digitifera to elevated temperature. Microbiologyopen 2017; 6. [PMID: 28425179 PMCID: PMC5552946 DOI: 10.1002/mbo3.478] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/22/2017] [Accepted: 03/07/2017] [Indexed: 12/22/2022] Open
Abstract
The coral is a holobiont formed by the close interaction between the coral animal and a diverse community of microorganisms, including dinoflagellates, bacteria, archaea, fungi, and viruses. The prokaryotic symbionts of corals are important for host fitness but are also highly sensitive to changes in the environment. In this study, we used 16S ribosomal RNA (rRNA) sequencing to examine the response of the microbial community associated with the coral, Acropora digitifera, to elevated temperature. The A. digitifera microbial community is dominated by operational taxonomic unit (OTUs) affiliated with classes Alphaproteobacteria and Gammaproteobacteria. The prokaryotic community in the coral tissue is distinct from that of the mucus and the surrounding seawater. Remarkably, the overall microbial community structure of A. digitifera remained stable for 10 days of continuous exptosure at 32°C compared to corals maintained at 27°C. However, the elevated temperature regime resulted in a decrease in the abundance of OTUs affiliated with certain groups of bacteria, such as order Rhodobacterales. On the other hand, some OTUs affiliated with the orders Alteromonadales, Vibrionales, and Flavobacteriales, which are often associated with diseased and stressed corals, increased in abundance. Thus, while the A. digitifera bacterial community structure appears resilient to higher temperature, prolonged exposure and intensified stress results in changes in the abundance of specific microbial community members that may affect the overall metabolic state and health of the coral holobiont.
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Affiliation(s)
- Andrian P Gajigan
- Marine Science Institute, University of the Philippines, Diliman, Quezon City, Philippines
| | - Leomir A Diaz
- Marine Science Institute, University of the Philippines, Diliman, Quezon City, Philippines
| | - Cecilia Conaco
- Marine Science Institute, University of the Philippines, Diliman, Quezon City, Philippines
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The effects of elevated seawater temperatures on Caribbean gorgonian corals and their algal symbionts, Symbiodinium spp. PLoS One 2017; 12:e0171032. [PMID: 28152002 PMCID: PMC5289496 DOI: 10.1371/journal.pone.0171032] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 01/14/2017] [Indexed: 11/19/2022] Open
Abstract
Global climate change not only leads to elevated seawater temperatures but also to episodic anomalously high or low temperatures lasting for several hours to days. Scleractinian corals are detrimentally affected by thermal fluctuations, which often lead to an uncoupling of their mutualism with Symbiodinium spp. (coral bleaching) and potentially coral death. Consequently, on many Caribbean reefs scleractinian coral cover has plummeted. Conversely, gorgonian corals persist, with their abundance even increasing. How gorgonians react to thermal anomalies has been investigated utilizing limited parameters of either the gorgonian, Symbiodinium or the combined symbiosis (holobiont). We employed a holistic approach to examine the effect of an experimental five-day elevated temperature episode on parameters of the host, symbiont, and the holobiont in Eunicea tourneforti, E. flexuosa and Pseudoplexaura porosa. These gorgonian corals reacted and coped with 32°C seawater temperatures. Neither Symbiodinium genotypes nor densities differed between the ambient 29.5°C and 32°C. Chlorophyll a and c2 per Symbiodinium cell, however, were lower at 32°C leading to a reduction in chlorophyll content in the branches and an associated reduction in estimated absorbance and increase in the chlorophyll a specific absorption coefficient. The adjustments in the photochemical parameters led to changes in photochemical efficiencies, although these too showed that the gorgonians were coping. For example, the maximum excitation pressure, Qm, was significantly lower at 32°C than at 29.5°C. In addition, although per dry weight the amount of protein and lipids were lower at 32°C, the overall energy content in the tissues did not differ between the temperatures. Antioxidant activity either remained the same or increased following exposure to 32°C further reiterating a response that dealt with the stressor. Taken together, the capability of Caribbean gorgonian corals to modify symbiont, host and consequently holobiont parameters may partially explain their persistence on reefs faced with climate change.
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Validation of reference genes for cryopreservation studies with the gorgonian coral endosymbiont Symbiodinium. Sci Rep 2017; 7:39396. [PMID: 28067273 PMCID: PMC5220285 DOI: 10.1038/srep39396] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 11/23/2016] [Indexed: 12/18/2022] Open
Abstract
Quantification by real-time RT-PCR requires a stable internal reference known as a housekeeping gene (HKG) for normalising the mRNA levels of target genes. The present study identified and validated stably expressed HKGs in post-thaw Symbiodinium clade G. Six potential HKGs, namely, pcna, gapdh, 18S rRNA, hsp90, rbcl, and ps1, were analysed using three different algorithms, namely, GeNorm, NormFinder, and BestKeeper. The GeNorm algorithm ranked the candidate genes as follows in the order of decreasing stability: pcna and gapdh > ps1 > 18S rRNA > hsp90 > rbcl. Results obtained using the NormFinder algorithm also showed that pcna was the most stable HKG and ps1 was the second most stable HKG. We found that the candidate HKGs examined in this study showed variable stability with respect to the three algorithms. These results indicated that both pcna and ps1 were suitable for normalising target gene expression determined by performing real-time RT-PCR in cryopreservation studies on Symbiodinium clade G. The results of the present study would help future studies to elucidate the effect of cryopreservation on gene expression in dinoflagellates.
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Béchet Q, Laviale M, Arsapin N, Bonnefond H, Bernard O. Modeling the impact of high temperatures on microalgal viability and photosynthetic activity. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:136. [PMID: 28559927 PMCID: PMC5446765 DOI: 10.1186/s13068-017-0823-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Accepted: 05/17/2017] [Indexed: 05/18/2023]
Abstract
BACKGROUND Culture collapse due to high temperatures can significantly impact the profitability of outdoor algal cultivation systems. The objective of this study was to model for the first time the impact of high temperatures on algal activity and viability. RESULTS Viability measurements on Dunaliella salina cultures were based on cytometry with two fluorescent markers (erythrosine and fluorescein di-acetate), and photosynthetic activity was measured by Pulse Amplitude Modulation (PAM) fluorometry. Kinetic studies revealed that viability and activity losses during exposure to high temperatures could be described by a Weibull model. Both mortality and activity were shown to be functions of the thermal dose received by the algae, defined as the product of duration of exposure to high temperatures and an exponential function of temperature. Simulations at five climatic locations revealed that culture collapse due to high temperatures could impact productivity of D. salina in non-temperature-controlled outdoor photobioreactors by 35 and 40% in arid and Mediterranean climates, respectively. CONCLUSIONS The model developed in this study can be used to forecast the impact of high temperatures on algal biofuel productivity. When coupled with models predicting the temperature of outdoor cultivation systems, this model can also be used to select the best combination of location, system geometry, and algal species to minimize the risks of culture collapse and therefore maximize biofuel productivity.
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Affiliation(s)
- Quentin Béchet
- Université Côte d’Azur, Inria, BIOCORE, BP 93, 06902 Sophia Antipolis Cedex, France
- Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 7093, LOV, Observatoire océanologique, 06230 Villefranche/Mer, France
| | - Martin Laviale
- Université Côte d’Azur, Inria, BIOCORE, BP 93, 06902 Sophia Antipolis Cedex, France
- Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 7093, LOV, Observatoire océanologique, 06230 Villefranche/Mer, France
| | - Nicolas Arsapin
- Université Côte d’Azur, Inria, BIOCORE, BP 93, 06902 Sophia Antipolis Cedex, France
- Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 7093, LOV, Observatoire océanologique, 06230 Villefranche/Mer, France
| | - Hubert Bonnefond
- Université Côte d’Azur, Inria, BIOCORE, BP 93, 06902 Sophia Antipolis Cedex, France
- Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 7093, LOV, Observatoire océanologique, 06230 Villefranche/Mer, France
| | - Olivier Bernard
- Université Côte d’Azur, Inria, BIOCORE, BP 93, 06902 Sophia Antipolis Cedex, France
- Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 7093, LOV, Observatoire océanologique, 06230 Villefranche/Mer, France
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Pey A, Zamoum T, Christen R, Merle PL, Furla P. Characterization of glutathione peroxidase diversity in the symbiotic sea anemone Anemonia viridis. Biochimie 2017; 132:94-101. [DOI: 10.1016/j.biochi.2016.10.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 10/20/2016] [Indexed: 02/01/2023]
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Gardner SG, Raina JB, Ralph PJ, Petrou K. Reactive oxygen species (ROS) and dimethylated sulphur compounds in coral explants under acute thermal stress. J Exp Biol 2017; 220:1787-1791. [DOI: 10.1242/jeb.153049] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 03/02/2017] [Indexed: 11/20/2022]
Abstract
Coral bleaching is intensifying with global climate change. While the causes for these catastrophic events are well understood, the cellular mechanism that triggers bleaching is not well established. Our understanding of coral bleaching processes is hindered by the lack of robust methods for studying interactions between host and symbiont at the single-cell level. Here we exposed coral explants to acute thermal stress and measured oxidative stress, more specifically, reactive oxygen species (ROS), in individual symbiont cells. Furthermore, we measured concentrations of dimethylsulphoniopropionate (DMSP) and dimethylsulphoxide (DMSO) to elucidate the role of these compounds in coral antioxidant function. This work demonstrates the application of coral explants for investigating coral physiology and biochemistry under thermal stress and delivers a new approach to study host-symbiont interactions at the microscale, allowing us to directly link intracellular ROS with DMSP and DMSO dynamics.
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Affiliation(s)
- Stephanie G. Gardner
- Climate Change Cluster, University of Technology Sydney, Ultimo, 2007 NSW, Australia
- School of Life Sciences, University of Technology Sydney, Ultimo, 2007 NSW, Australia
| | - Jean-Baptiste Raina
- Climate Change Cluster, University of Technology Sydney, Ultimo, 2007 NSW, Australia
| | - Peter J. Ralph
- Climate Change Cluster, University of Technology Sydney, Ultimo, 2007 NSW, Australia
| | - Katherina Petrou
- School of Life Sciences, University of Technology Sydney, Ultimo, 2007 NSW, Australia
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Rehman AU, Szabó M, Deák Z, Sass L, Larkum A, Ralph P, Vass I. Symbiodinium sp. cells produce light-induced intra- and extracellular singlet oxygen, which mediates photodamage of the photosynthetic apparatus and has the potential to interact with the animal host in coral symbiosis. THE NEW PHYTOLOGIST 2016; 212:472-484. [PMID: 27321415 DOI: 10.1111/nph.14056] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 05/08/2016] [Indexed: 06/06/2023]
Abstract
Coral bleaching is an important environmental phenomenon, whose mechanism has not yet been clarified. The involvement of reactive oxygen species (ROS) has been implicated, but direct evidence of what species are involved, their location and their mechanisms of production remains unknown. Histidine-mediated chemical trapping and singlet oxygen sensor green (SOSG) were used to detect intra- and extracellular singlet oxygen ((1) O2 ) in Symbiodinium cultures. Inhibition of the Calvin-Benson cycle by thermal stress or high light promotes intracellular (1) O2 formation. Histidine addition, which decreases the amount of intracellular (1) O2 , provides partial protection against photosystem II photoinactivation and chlorophyll (Chl) bleaching. (1) O2 production also occurs in cell-free medium of Symbiodinium cultures, an effect that is enhanced under heat and light stress and can be attributed to the excretion of (1) O2 -sensitizing metabolites from the cells. Confocal microscopy imaging using SOSG showed most extracellular (1) O2 around the cell surface, but it is also produced across the medium distant from the cells. We demonstrate, for the first time, both intra- and extracellular (1) O2 production in Symbiodinium cultures. Intracellular (1) O2 is associated with photosystem II photodamage and pigment bleaching, whereas extracellular (1) O2 has the potential to mediate the breakdown of symbiotic interaction between zooxanthellae and their animal host during coral bleaching.
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Affiliation(s)
- Ateeq Ur Rehman
- Institute of Plant Biology, Biological Research Center of the Hungarian Academy of Sciences, PO Box 521, H-6701, Szeged, Hungary
| | - Milán Szabó
- Plant Functional Biology and Climate Change Cluster (C3), University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
- Division of Plant Sciences, Research School of Biology, The Australian National University, 46 Sullivans Creek Road, Acton, ACT, 2601, Australia
| | - Zsuzsanna Deák
- Institute of Plant Biology, Biological Research Center of the Hungarian Academy of Sciences, PO Box 521, H-6701, Szeged, Hungary
| | - László Sass
- Institute of Plant Biology, Biological Research Center of the Hungarian Academy of Sciences, PO Box 521, H-6701, Szeged, Hungary
| | - Anthony Larkum
- Plant Functional Biology and Climate Change Cluster (C3), University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
| | - Peter Ralph
- Plant Functional Biology and Climate Change Cluster (C3), University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia
| | - Imre Vass
- Institute of Plant Biology, Biological Research Center of the Hungarian Academy of Sciences, PO Box 521, H-6701, Szeged, Hungary.
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“Super-quenching” state protects Symbiodinium from thermal stress — Implications for coral bleaching. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:840-7. [DOI: 10.1016/j.bbabio.2016.02.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 02/05/2016] [Indexed: 11/19/2022]
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