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Rosic N, Delamare-Deboutteville J, Dove S. Heat stress in symbiotic dinoflagellates: Implications on oxidative stress and cellular changes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 944:173916. [PMID: 38866148 DOI: 10.1016/j.scitotenv.2024.173916] [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: 12/30/2023] [Revised: 05/18/2024] [Accepted: 06/08/2024] [Indexed: 06/14/2024]
Abstract
Global warming has been shown to harmfully affect symbiosis between Symbiodiniaceae and other marine invertebrates. When symbiotic dinoflagellates (the genus Breviolum) were in vitro exposed to acute heat stress of +7 °C for a period of 5 days, the results revealed the negative impact on all physiological and other cellular parameters measured. Elevated temperatures resulted in a severe reduction in algal density of up to 9.5-fold, as well as pigment concentrations, indicating the status of the physiological stress and early signs of photo-bleaching. Reactive oxygen species (ROS) were increased in all heated dinoflagellate cells, while the antioxidant-reduced glutathione levels initially dropped on day one but increased under prolonged temperature stress. The cell viability parameters were reduced by 97 % over the heating period, with an increased proportion of apoptotic and necrotic cells. Autofluorescence (AF) for Cy5-PE 660-20 was reduced from 1.7-fold at day 1 to up to 50-fold drop at the end of heating time, indicating that the AF changes were highly sensitive to heat stress and that it could be an extremely sensitive tool for assessing the functionality of algal photosynthetic machinery. The addition of the drug 5-AZA-2'-deoxycytidine (5-AZA), which inhibits DNA methylation processes, was assessed in parallel and contributed to some alterations in algal cellular stress response. The presence of drug 5-AZA combined with the temperature stress had an additional impact on Symbiodiniaceae density and cell complexity, including the AF levels. These variations in cellular stress response under heat stress and compromised DNA methylation conditions may indicate the importance of this epigenetic mechanism for symbiotic dinoflagellate thermal tolerance adaptability over a longer period, which needs further exploration. Consequently, the increased ROS levels and changes in AF signals reported during ongoing heat stress in dinoflagellate cells could be used as early stress biomarkers in these microalgae and potentially other photosynthetic species.
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Affiliation(s)
- Nedeljka Rosic
- Faculty of Health, Southern Cross University, Gold Coast, QLD, Australia; Marine Ecology Research Centre, Southern Cross University, Lismore, NSW, Australia.
| | | | - Sophie Dove
- School of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia
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2
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Wuitchik DM, Aichelman HE, Atherton KF, Brown CM, Chen X, DiRoberts L, Pelose GE, Tramonte CA, Davies SW. Photosymbiosis reduces the environmental stress response under a heat challenge in a facultatively symbiotic coral. Sci Rep 2024; 14:15484. [PMID: 38969663 PMCID: PMC11226616 DOI: 10.1038/s41598-024-66057-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 06/26/2024] [Indexed: 07/07/2024] Open
Abstract
The symbiosis between corals and dinoflagellates of the family Symbiodiniaceae is sensitive to environmental stress. The oxidative bleaching hypothesis posits that extreme temperatures lead to accumulation of photobiont-derived reactive oxygen species ROS, which exacerbates the coral environmental stress response (ESR). To understand how photosymbiosis modulates coral ESRs, these responses must be explored in hosts in and out of symbiosis. We leveraged the facultatively symbiotic coral Astrangia poculata, which offers an opportunity to uncouple the ESR across its two symbiotic phenotypes (brown, white). Colonies of both symbiotic phenotypes were exposed to three temperature treatments for 15 days: (i) control (static 18 °C), (ii) heat challenge (increasing from 18 to 30 °C), and (iii) cold challenge (decreasing from 18 to 4 °C) after which host gene expression was profiled. Cold challenged corals elicited widespread differential expression, however, there were no differences between symbiotic phenotypes. In contrast, brown colonies exhibited greater gene expression plasticity under heat challenge, including enrichment of cell cycle pathways involved in controlling photobiont growth. While this plasticity was greater, the genes driving this plasticity were not associated with an amplified environmental stress response (ESR) and instead showed patterns of a dampened ESR under heat challenge. This provides nuance to the oxidative bleaching hypothesis and suggests that, at least during the early onset of bleaching, photobionts reduce the host's ESR under elevated temperatures in A. poculata.
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Affiliation(s)
- D M Wuitchik
- Department of Biology, Boston University, Boston, MA, USA.
- Department of Biology, Tufts University, Medford, MA, USA.
| | - H E Aichelman
- Department of Biology, Boston University, Boston, MA, USA
| | - K F Atherton
- Department of Biology, Boston University, Boston, MA, USA
- Bioinformatics Graduate Program, Boston University, Boston, MA, USA
| | - C M Brown
- Department of Biology, Boston University, Boston, MA, USA
| | - X Chen
- Department of Biology, Boston University, Boston, MA, USA
| | - L DiRoberts
- Department of Biology, Boston University, Boston, MA, USA
| | - G E Pelose
- Department of Biology, Boston University, Boston, MA, USA
| | - C A Tramonte
- Department of Biology, Boston College, Boston, MA, USA
| | - S W Davies
- Department of Biology, Boston University, Boston, MA, USA.
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3
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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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4
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Liu C, Zhang Y, Botana MT, Fu Y, Huang L, Jiang L, Yu X, Luo Y, Huang H. The bioenergetics response of the coral Pocillopora damicornis to temperature changes during its reproduction stage. MARINE ENVIRONMENTAL RESEARCH 2024; 198:106557. [PMID: 38823094 DOI: 10.1016/j.marenvres.2024.106557] [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: 02/25/2024] [Revised: 04/21/2024] [Accepted: 05/14/2024] [Indexed: 06/03/2024]
Abstract
Sexual reproduction of reef-building corals is vital for coral reef ecosystem recovery. Corals allocate limited energy to growth and reproduction, when being under environmental disturbance, which ultimately shapes the community population dynamics. In the present study, energetic and physiological parameters of both parental colonies and larvae of the coral Pocillopora damicornis were measured during their reproduction stage under four temperatures; 28 °C (low-temperature acclimation, LA), 29 °C (control temperature, CT), 31 °C (high-temperature acclimation, HA), and 32 °C (heat stress, HS). The results showed temperature changes altered the larvae release timing and fecundity in P. damicornis. Parental colonies exposed to the LA treatment exhibited reduced investment in reproduction and released fewer larvae, while retaining more energy for their development. However, each larva acquired higher energy and symbiont densities enabling survival through longer planktonic periods before settlement. In contrast, parental colonies exposed to the HA treatment had increased investment for reproduction and larvae output, while per larva gained less energy to mitigate the threat of higher temperature. Furthermore, the energy allocation processes restructured fatty acids concentration and composition in both parental colonies and larvae as indicated by shifts in membrane fluidity under adaptable temperature changes. Notably, parental colonies from the HS treatment expended more energy in response to heat stress, resulting in adverse effects, especially after larval release. Our study expands the current knowledge on the energy allocation strategies of P. damicornis and how it is impacted by temperature. Parental colonies employed different energy allocation strategies under distinct temperature regimes to optimize their development and offspring success, but under heat stress, both were compromised. Lipid metabolism is essential for the success of coral reproduction and further understanding their response to heat stress can improve intervention strategies for coral reef conservation in warmer future oceans.
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Affiliation(s)
- Chengyue Liu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China; Department of Ocean Science and Hong Kong Branch (HKB) of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology (HKUST), Hong Kong, China.
| | - Yuyang Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Marina Tonetti Botana
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Yousi Fu
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA
| | - Lintao Huang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Lei Jiang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China; Department of Ocean Science and Hong Kong Branch (HKB) of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology (HKUST), Hong Kong, China
| | - Xiaolei Yu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Yong Luo
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA; CAS-HKUST Sanya Joint Laboratory of Marine Science Research, Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya, China
| | - Hui Huang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research, Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya, China; Sanya National Marine Ecosystem Research Station, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, China.
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5
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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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6
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Han S, Cheng X, Wang T, Li X, Cai Z, Zheng H, Xiao B, Zhou J. AI-2 quorum sensing signal disrupts coral symbiotic homeostasis and induces host bleaching. ENVIRONMENT INTERNATIONAL 2024; 188:108768. [PMID: 38788416 DOI: 10.1016/j.envint.2024.108768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 04/19/2024] [Accepted: 05/20/2024] [Indexed: 05/26/2024]
Abstract
Symbiotic microorganisms play critical ecophysiological roles that facilitate the maintenance of coral health. Currently, information on the gene and protein pathways contributing to bleaching responses is lacking, including the role of autoinducers. Although the autoinducer AI-1 is well understood, information on AI-2 is insufficient. Here, we observed a 3.7-4.0 times higher abundance of the AI-2 synthesis gene luxS in bleached individuals relative to their healthy counterparts among reef-building coral samples from the natural environment. Laboratory tests further revealed that AI-2 contributed significantly to an increase in coral bleaching, altered the ratio of potential probiotic and pathogenic bacteria, and suppressed the antiviral activity of specific pathogenic bacteria while enhancing their functional potential, such as energy metabolism, chemotaxis, biofilm formation and virulence release. Structural equation modeling indicated that AI-2 influences the microbial composition, network structure, and pathogenic features, which collectively contribute to the coral bleaching status. Collectively, our results offer novel potential strategies for coral conservation based on a signal manipulation approach.
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Affiliation(s)
- Shuo Han
- Marine Ecology and Human Factors Assessment Technical Innovation Center of Natural Resources Ministry, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Key Laboratory of Advanced Technology for Marine Ecology, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China
| | - Xueyu Cheng
- Marine Ecology and Human Factors Assessment Technical Innovation Center of Natural Resources Ministry, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Key Laboratory of Advanced Technology for Marine Ecology, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China
| | - Tao Wang
- Marine Ecology and Human Factors Assessment Technical Innovation Center of Natural Resources Ministry, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China
| | - Xinyang Li
- Marine Ecology and Human Factors Assessment Technical Innovation Center of Natural Resources Ministry, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Key Laboratory of Advanced Technology for Marine Ecology, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China
| | - Zhonghua Cai
- Marine Ecology and Human Factors Assessment Technical Innovation Center of Natural Resources Ministry, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China
| | - Huina Zheng
- Guangdong Ocean University Shenzhen Research Institute, Shenzhen 518055, PR China
| | - Baohua Xiao
- Guangdong Ocean University Shenzhen Research Institute, Shenzhen 518055, PR China
| | - Jin Zhou
- Marine Ecology and Human Factors Assessment Technical Innovation Center of Natural Resources Ministry, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Public Platform for Screening and Application of Marine Microbial Resources, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China; Shenzhen Key Laboratory of Advanced Technology for Marine Ecology, Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, PR China.
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7
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Chen X, Liao X, Chang S, Chen Z, Yang Q, Peng J, Hu W, Zhang X. Comprehensive insights into the differences of fungal communities at taxonomic and functional levels in stony coral Acropora intermedia under a natural bleaching event. MARINE ENVIRONMENTAL RESEARCH 2024; 196:106419. [PMID: 38408405 DOI: 10.1016/j.marenvres.2024.106419] [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: 10/25/2023] [Revised: 01/23/2024] [Accepted: 02/21/2024] [Indexed: 02/28/2024]
Abstract
Previous studies have reported the correlations between bacterial communities and coral bleaching, but the knowledge of fungal roles in coral bleaching is still limited. In this study, the taxonomic and functional diversities of fungi in unbleached, partly bleached and bleached stony coral Acropora intermedia were investigated through the ITS-rRNA gene next-generation sequencing. An unexpected diversity of successfully classified fungi (a total of 167 fungal genera) was revealed in this study, and the partly bleached coral samples gained the highest fungal diversity, followed by bleached and unbleached coral samples. Among these fungi, 122 genera (nearly 73.2%) were rarely found in corals in previous studies, such as Calostoma and Morchella, which gave us a more comprehensive understanding of coral-associated fungi. Positively correlated fungal genera (Calostoma, Corticium, Derxomyces, Fusicolla, Penicillium and Vishniacozyma) and negative correlated fungal genera (Blastobotrys, Exophiala and Dacryopinax) with the coral bleaching were both detected. It was found that a series of fungal genera, dominant by Apiotrichum, a source of opportunistic infections, was significantly enriched; while another fungal group majoring in Fusicolla, a probiotic fungus, was distinctly depressed in the bleached coral. It was also noteworthy that the abundance of pathogenic fungi, including Fusarium, Didymella and Trichosporon showed a rising trend; while the saprotrophic fungi, including Tricladium, Botryotrichum and Scleropezicula demostrated a declining trend as the bleaching deteriorating. The rising of pathogenic fungi and the declining of saprotrophic fungi revealed the basic rules of fungal community transitions in the coral bleaching, but the mechanism of coral-associated fungal interactions still lacks further investigation. Overall, this is an investigation focused on the differences of fungal communities at taxonomic and functional levels in stony coral A. intermedia under different bleaching statuses, which provides a better comprehension of the correlations between fungal communities and the coral bleaching.
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Affiliation(s)
- Xinye Chen
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Xinyu Liao
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Shihan Chang
- University of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Zihui Chen
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Qiaoting Yang
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Jingjing Peng
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Weihui Hu
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China.
| | - Xiaoyong Zhang
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China.
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8
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Bhattacharya D, Stephens TG, Chille EE, Benites LF, Chan CX. Facultative lifestyle drives diversity of coral algal symbionts. Trends Ecol Evol 2024; 39:239-247. [PMID: 37953106 DOI: 10.1016/j.tree.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 10/11/2023] [Accepted: 10/12/2023] [Indexed: 11/14/2023]
Abstract
The photosynthetic symbionts of corals sustain biodiverse reefs in nutrient-poor, tropical waters. Recent genomic data illuminate the evolution of coral symbionts under genome size constraints and suggest that retention of the facultative lifestyle, widespread among these algae, confers a selective advantage when compared with a strict symbiotic existence. We posit that the coral symbiosis is analogous to a 'bioreactor' that selects winner genotypes and allows them to rise to high numbers in a sheltered habitat prior to release by the coral host. Our observations lead to a novel hypothesis, the 'stepping-stone model', which predicts that local adaptation under both the symbiotic and free-living stages, in a stepwise fashion, accelerates coral alga diversity and the origin of endemic strains and species.
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Affiliation(s)
- Debashish Bhattacharya
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA.
| | - Timothy G Stephens
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA
| | - Erin E Chille
- Ecology and Evolution Graduate Program, Rutgers University, New Brunswick, NJ 08901, USA
| | - L Felipe Benites
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA
| | - Cheong Xin Chan
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, 4072, QLD, Australia.
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9
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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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10
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Maire J, Philip GK, Livingston J, Judd LM, Blackall LL, van Oppen MJH. Functional potential and evolutionary response to long-term heat selection of bacterial associates of coral photosymbionts. mSystems 2023; 8:e0086023. [PMID: 37909753 PMCID: PMC10746172 DOI: 10.1128/msystems.00860-23] [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: 08/14/2023] [Accepted: 09/28/2023] [Indexed: 11/03/2023] Open
Abstract
IMPORTANCE Symbiotic microorganisms are crucial for the survival of corals and their resistance to coral bleaching in the face of climate change. However, the impact of microbe-microbe interactions on coral functioning is mostly unknown but could be essential factors for coral adaption to future climates. Here, we investigated interactions between cultured dinoflagellates of the Symbiodiniaceae family, essential photosymbionts of corals, and associated bacteria. By assessing the genomic potential of 49 bacteria, we found that they are likely beneficial for Symbiodiniaceae, through the production of B vitamins and antioxidants. Additionally, bacterial genes involved in host-symbiont interactions, such as secretion systems, accumulated mutations following long-term exposure to heat, suggesting symbiotic interactions may change under climate change. This highlights the importance of microbe-microbe interactions in coral functioning.
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Affiliation(s)
- Justin Maire
- School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Gayle K. Philip
- Melbourne Bioinformatics, The University of Melbourne, Parkville, Victoria, Australia
| | - Jadzia Livingston
- School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Louise M. Judd
- Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
| | - Linda L. Blackall
- School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Madeleine J. H. van Oppen
- School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
- Australian Institute of Marine Science, Townsville, Queensland, Australia
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11
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Ishida H, John U, Murray SA, Bhattacharya D, Chan CX. Developing model systems for dinoflagellates in the post-genomic era. JOURNAL OF PHYCOLOGY 2023; 59:799-808. [PMID: 37657822 DOI: 10.1111/jpy.13386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 08/16/2023] [Indexed: 09/03/2023]
Abstract
Dinoflagellates are a diverse group of eukaryotic microbes that are ubiquitous in aquatic environments. Largely photosynthetic, they encompass symbiotic, parasitic, and free-living lineages with a broad spectrum of trophism. Many free-living taxa can produce bioactive secondary metabolites such as biotoxins, some of which cause harmful algal blooms. In contrast, most symbiotic species are crucial for sustaining coral reef health. The year 2023 marked a decade since the first genome data of dinoflagellates became available. The growing genome-scale resources for these taxa are highlighting their remarkable evolutionary and genomic complexities. Here, we discuss the prospect of developing dinoflagellate models using the criteria of accessibility, tractability, resources, research support, and promise. Moving forward in the post-genomic era, we argue for the development of fit-to-purpose models that tailor to specific biological contexts, and that a one-size-fits-all model is inadequate for encapsulating the complex biology, ecology, and evolutionary history of dinoflagellates.
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Affiliation(s)
- Hisatake Ishida
- School of Chemistry and Molecular Biosciences, Australian Centre for Ecogenomics, The University of Queensland, Brisbane, Queensland, Australia
| | - Uwe John
- Alfred-Wegener-Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Helmholtz Institute for Functional Marine Biodiversity, Oldenburg, Germany
| | - Shauna A Murray
- School of Life Sciences, University of Technology Sydney, Ultimo, New South Wales, Australia
| | - Debashish Bhattacharya
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, New Jersey, USA
| | - Cheong Xin Chan
- School of Chemistry and Molecular Biosciences, Australian Centre for Ecogenomics, The University of Queensland, Brisbane, Queensland, Australia
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12
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Mardones ML, Lambert J, Wiedenmann J, Davies TW, Levy O, D'Angelo C. Artificial light at night (ALAN) disrupts behavioural patterns of reef corals. MARINE POLLUTION BULLETIN 2023; 194:115365. [PMID: 37579595 DOI: 10.1016/j.marpolbul.2023.115365] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 07/27/2023] [Accepted: 07/30/2023] [Indexed: 08/16/2023]
Abstract
Increasing levels of Artificial Light At Night (ALAN) alter the natural diel cycles of organisms at global scale. ALAN constitutes a potential threat to the light-dependent functioning of symbiotic scleractinian corals, the habit-founders of warm, shallow water reefs. Here, we show that ALAN disrupts the natural diel tentacle expansion and contraction behaviour, a key mechanism for prey capture and nutrient acquisition in corals. We exposed four symbiotic scleractinian coral species to different ALAN treatments (0.4-2.5 μmol quanta m-2 s-1). Exposure to ALAN levels of 1.2 μmol quanta m-2 s-1 and above altered the normal tentacle expansion response in diurnal species (Stylophora pistillata and Duncanopsammia axifuga). The tentacle expansion pattern of nocturnal species (Montastraea cavernosa and Lobophyllia hemprichii) was less affected, which may indicate a greater capacity to tolerate ALAN exposure. The results of this work suggest that ALAN has the potential to affect nutrient acquisition mechanisms of symbiotic corals which may in turn result in changes in the coral community structure in shallow water reefs in ALAN-exposed areas.
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Affiliation(s)
- M L Mardones
- Coral Reef Laboratory, University of Southampton, European Way, Southampton, UK
| | - J Lambert
- Coral Reef Laboratory, University of Southampton, European Way, Southampton, UK
| | - J Wiedenmann
- Coral Reef Laboratory, University of Southampton, European Way, Southampton, UK
| | - T W Davies
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
| | - O Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Israel; Israel The H. Steinitz Marine Biology Laboratory, The Interuniversity Institute for Marine Sciences of Eilat, Israel
| | - C D'Angelo
- Coral Reef Laboratory, University of Southampton, European Way, Southampton, UK.
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13
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Wuerz M, Lawson CA, Oakley CA, Possell M, Wilkinson SP, Grossman AR, Weis VM, Suggett DJ, Davy SK. Symbiont Identity Impacts the Microbiome and Volatilome of a Model Cnidarian-Dinoflagellate Symbiosis. BIOLOGY 2023; 12:1014. [PMID: 37508443 PMCID: PMC10376011 DOI: 10.3390/biology12071014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/28/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023]
Abstract
The symbiosis between cnidarians and dinoflagellates underpins the success of reef-building corals in otherwise nutrient-poor habitats. Alterations to symbiotic state can perturb metabolic homeostasis and thus alter the release of biogenic volatile organic compounds (BVOCs). While BVOCs can play important roles in metabolic regulation and signalling, how the symbiotic state affects BVOC output remains unexplored. We therefore characterised the suite of BVOCs that comprise the volatilome of the sea anemone Exaiptasia diaphana ('Aiptasia') when aposymbiotic and in symbiosis with either its native dinoflagellate symbiont Breviolum minutum or the non-native symbiont Durusdinium trenchii. In parallel, the bacterial community structure in these different symbiotic states was fully characterised to resolve the holobiont microbiome. Based on rRNA analyses, 147 unique amplicon sequence variants (ASVs) were observed across symbiotic states. Furthermore, the microbiomes were distinct across the different symbiotic states: bacteria in the family Vibrionaceae were the most abundant in aposymbiotic anemones; those in the family Crocinitomicaceae were the most abundant in anemones symbiotic with D. trenchii; and anemones symbiotic with B. minutum had the highest proportion of low-abundance ASVs. Across these different holobionts, 142 BVOCs were detected and classified into 17 groups based on their chemical structure, with BVOCs containing multiple functional groups being the most abundant. Isoprene was detected in higher abundance when anemones hosted their native symbiont, and dimethyl sulphide was detected in higher abundance in the volatilome of both Aiptasia-Symbiodiniaceae combinations relative to aposymbiotic anemones. The volatilomes of aposymbiotic anemones and anemones symbiotic with B. minutum were distinct, while the volatilome of anemones symbiotic with D. trenchii overlapped both of the others. Collectively, our results are consistent with previous reports that D. trenchii produces a metabolically sub-optimal symbiosis with Aiptasia, and add to our understanding of how symbiotic cnidarians, including corals, may respond to climate change should they acquire novel dinoflagellate partners.
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Affiliation(s)
- Maggie Wuerz
- School of Biological Sciences, Victoria University of Wellington, Wellington 6012, New Zealand
| | - Caitlin A Lawson
- Climate Change Cluster, University of Technology Sydney, Sydney Broadway, Sydney, NSW 2007, Australia
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Clinton A Oakley
- School of Biological Sciences, Victoria University of Wellington, Wellington 6012, New Zealand
| | - Malcolm Possell
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
| | | | - Arthur R Grossman
- Carnegie Institution for Science, Department of Plant Biology, Stanford, CA 94305, USA
| | - Virginia M Weis
- Department of Integrative Biology, Oregon State University, Corvallis, OR 97331, USA
| | - David J Suggett
- Climate Change Cluster, University of Technology Sydney, Sydney Broadway, Sydney, NSW 2007, Australia
- KAUST Reefscape Restoration Initiative (KRRI) and Red Sea Research Center (RSRC), King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Simon K Davy
- School of Biological Sciences, Victoria University of Wellington, Wellington 6012, New Zealand
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14
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Contardi M, Fadda M, Isa V, Louis YD, Madaschi A, Vencato S, Montalbetti E, Bertolacci L, Ceseracciu L, Seveso D, Lavorano S, Galli P, Athanassiou A, Montano S. Biodegradable Zein-Based Biocomposite Films for Underwater Delivery of Curcumin Reduce Thermal Stress Effects in Corals. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37376819 PMCID: PMC10360034 DOI: 10.1021/acsami.3c01166] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Abstract
Massive coral bleaching episodes induced by thermal stress are one of the first causes of coral death worldwide. Overproduction of reactive oxygen species (ROS) has been identified as one of the potential causes of symbiosis breakdown between polyps and algae in corals during extreme heat wave events. Here, we propose a new strategy for mitigating heat effects by delivering underwater an antioxidant to the corals. We fabricated zein/polyvinylpyrrolidone (PVP)-based biocomposite films laden with the strong and natural antioxidant curcumin as an advanced coral bleaching remediation tool. Biocomposites' mechanical, water contact angle (WCA), swelling, and release properties can be tuned thanks to different supramolecular rearrangements that occur by varying the zein/PVP weight ratio. Following immersion in seawater, the biocomposites became soft hydrogels that did not affect the coral's health in the short (24 h) and long periods (15 days). Laboratory bleaching experiments at 29 and 33 °C showed that coral colonies of Stylophora pistillata coated with the biocomposites had ameliorated conditions in terms of morphological aspects, chlorophyll content, and enzymatic activity compared to untreated colonies and did not bleach. Finally, biochemical oxygen demand (BOD) confirmed the full biodegradability of the biocomposites, showing a low potential environmental impact in the case of open-field application. These insights may pave the way for new frontiers in mitigating extreme coral bleaching events by combining natural antioxidants and biocomposites.
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Affiliation(s)
- Marco Contardi
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
| | - Marta Fadda
- Smart Materials, Istituto Italiano di Tecnologia, Genova 16163, Italy
| | - Valerio Isa
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
| | - Yohan D Louis
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
| | - Andrea Madaschi
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
| | - Sara Vencato
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
| | - Enrico Montalbetti
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
| | - Laura Bertolacci
- Smart Materials, Istituto Italiano di Tecnologia, Genova 16163, Italy
| | - Luca Ceseracciu
- Materials Characterization Facility, Istituto Italiano di Tecnologia, Genova 16163, Italy
| | - Davide Seveso
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
| | - Silvia Lavorano
- Costa Edutainment SpA - Acquario di Genova, Genova 16128, Italy
| | - Paolo Galli
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
- Dubai Business School, University of Dubai, Dubai 14143, United Arab Emirates
| | | | - Simone Montano
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Milan 20126, Italy
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll 12030, Republic of Maldives
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15
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Abd-Elgawad A, Cai R, Hellal A, Eltabakh M, Guo H, Mohamed F H, Xu C, Abou-Zaid M. Implementing a transformative approach to the coral reefs' recovery phase. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 879:163038. [PMID: 37003322 DOI: 10.1016/j.scitotenv.2023.163038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/28/2022] [Accepted: 03/20/2023] [Indexed: 05/17/2023]
Abstract
Mitigation and rehabilitation are responses to climate change and human misuse. However, many regions worldwide still lose coral reefs even after implementing these responses. We chose Hurghada city, on the Red Sea, and Weizhou island, on the South China Sea, as sample regions to assess their various modes of coral community structure loss against the combined climatic and human impact drivers that led to this shift. Despite the former being considered a regional coral refuge, while the latter was limited, both regions have previously intervened with coral restoration. We found that even after three decades of impact cessation by forcing laws, most coral reef states are still declining (about a third and a half in both cities), have not harnessed the existing crowded larval density, and are unrecovered. Such findings imply that the combined impacts will persist, necessitating a broad connectivity analysis that enables a suitable intervention (hybrid solutions hypothesis). Each state of coral categories was connected to certain combined stressor factors using our broad connectivity analysis to grasp the extent and relative contribution of coral community shift since our data obtained from comparable sites were widely varied. Moreover, destructive emerged changes have transformed the coral community structure under the forced adaptation scenario of the community structure, boosting those who can resist at the expense of others. To prove our hypothesis, we used the connectivity findings in determining the optimal technique and spots for coral rehabilitation around the two cities. We then compared our findings with the outcomes of two other existing adjacent restoration projects related to other endeavors. Our hybrid approach harvested coral larvae that had been wasted in both cities. Thus, hybrid solutions are globally required for such cases, and proper early interventions are needed to maintain the genotype power to boost coral adaptability throw global ecological settings.
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Affiliation(s)
- Amro Abd-Elgawad
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, PR China; Tourism Developing Authority, Central Administration for Environmental Affairs, Cairo, Egypt.
| | - Rongshuo Cai
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, PR China.
| | - Ahmed Hellal
- Al-Azhar University, Faculty of Science, Marine Biology & Ichthyology Branch, Cairo, Egypt
| | - Mohamed Eltabakh
- Al-Azhar University, Faculty of Science, Marine Biology & Ichthyology Branch, Cairo, Egypt
| | - Haixia Guo
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, PR China
| | - Hala Mohamed F
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, PR China; Al-Azhar University (Girls Branch), Faculty of Science, Botany & Microbiology Department, Cairo, Egypt
| | - Changan Xu
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, PR China
| | - Mohamed Abou-Zaid
- Al-Azhar University, Faculty of Science, Marine Biology & Ichthyology Branch, Cairo, Egypt
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16
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Doering T, Maire J, Chan WY, Perez-Gonzalez A, Meyers L, Sakamoto R, Buthgamuwa I, Blackall LL, van Oppen MJH. Comparing the Role of ROS and RNS in the Thermal Stress Response of Two Cnidarian Models, Exaiptasia diaphana and Galaxea fascicularis. Antioxidants (Basel) 2023; 12:antiox12051057. [PMID: 37237923 DOI: 10.3390/antiox12051057] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/24/2023] [Accepted: 04/29/2023] [Indexed: 05/28/2023] Open
Abstract
Coral reefs are threatened by climate change, because it causes increasingly frequent and severe summer heatwaves, resulting in mass coral bleaching and mortality. Coral bleaching is believed to be driven by an excess production of reactive oxygen (ROS) and nitrogen species (RNS), yet their relative roles during thermal stress remain understudied. Here, we measured ROS and RNS net production, as well as activities of key enzymes involved in ROS scavenging (superoxide dismutase and catalase) and RNS synthesis (nitric oxide synthase) and linked these metrics to physiological measurements of cnidarian holobiont health during thermal stress. We did this for both an established cnidarian model, the sea anemone Exaiptasia diaphana, and an emerging scleractinian model, the coral Galaxea fascicularis, both from the Great Barrier Reef (GBR). Increased ROS production was observed during thermal stress in both species, but it was more apparent in G. fascicularis, which also showed higher levels of physiological stress. RNS did not change in thermally stressed G. fascicularis and decreased in E. diaphana. Our findings in combination with variable ROS levels in previous studies on GBR-sourced E. diaphana suggest G. fascicularis is a more suitable model to study the cellular mechanisms of coral bleaching.
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Affiliation(s)
- Talisa Doering
- School of Biosciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Justin Maire
- School of Biosciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Wing Yan Chan
- School of Biosciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Alexis Perez-Gonzalez
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute of Infection and Immunity, Parkville, VIC 3010, Australia
- Melbourne Cytometry Platform, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Luka Meyers
- School of Biosciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Rumi Sakamoto
- School of Biosciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Isini Buthgamuwa
- School of Biosciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Linda L Blackall
- School of Biosciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Madeleine J H van Oppen
- School of Biosciences, The University of Melbourne, Parkville, VIC 3010, Australia
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
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17
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Shlesinger T, van Woesik R. Oceanic differences in coral-bleaching responses to marine heatwaves. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 871:162113. [PMID: 36773903 DOI: 10.1016/j.scitotenv.2023.162113] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 02/02/2023] [Accepted: 02/04/2023] [Indexed: 06/18/2023]
Abstract
Anomalously high ocean temperatures have increased in frequency, intensity, and duration over the last several decades because of greenhouse gas emissions that cause global warming and marine heatwaves. Reef-building corals are sensitive to such temperature anomalies that commonly lead to coral bleaching, mortality, and changes in community structure. Yet, despite these overarching effects, there are geographical differences in thermal regimes, evolutionary histories, and past disturbances that may lead to different bleaching responses of corals within and among oceans. Here we examined the overall bleaching responses of corals in the Atlantic, Indian, and Pacific Oceans, using both a spatially explicit Bayesian mixed-effects model and a deep-learning neural-network model. We used a 40-year global dataset encompassing 23,288 coral-reef surveys at 11,058 sites in 88 countries, from 1980 to 2020. Focusing on ocean-wide differences we assessed the relationships between the percentage of bleached corals and different temperature-related metrics alongside a suite of environmental variables. We found that while high sea-surface temperatures were consistently, and strongly, related to coral bleaching within all oceans, there were clear geographical differences in the relationships between coral bleaching and most environmental variables. For instance, there was an increase in coral bleaching with depth in the Atlantic Ocean whereas the opposite was observed in the Indian Ocean, and no clear trend could be seen in the Pacific Ocean. The standard deviation of thermal-stress anomalies was negatively related to coral bleaching in the Atlantic and Pacific Oceans, but not in the Indian Ocean. Globally, coral bleaching has progressively occurred at higher temperatures over the last four decades within the Atlantic, Indian, and Pacific Oceans, although, again, there were differences among the three oceans. Together, such patterns highlight that historical circumstances and geographical differences in oceanographic conditions play a central role in contemporary coral-bleaching responses.
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Affiliation(s)
- Tom Shlesinger
- Institute for Global Ecology, Florida Institute of Technology, Melbourne 32901, FL, USA
| | - Robert van Woesik
- Institute for Global Ecology, Florida Institute of Technology, Melbourne 32901, FL, USA.
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18
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Baum JK, Claar DC, Tietjen KL, Magel JMT, Maucieri DG, Cobb KM, McDevitt-Irwin JM. Transformation of coral communities subjected to an unprecedented heatwave is modulated by local disturbance. SCIENCE ADVANCES 2023; 9:eabq5615. [PMID: 37018404 DOI: 10.1126/sciadv.abq5615] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 03/08/2023] [Indexed: 06/19/2023]
Abstract
Corals are imminently threatened by climate change-amplified marine heatwaves. However, how to conserve coral reefs remains unclear, since those without local anthropogenic disturbances often seem equally or more susceptible to thermal stress as impacted ones. We disentangle this apparent paradox, revealing that the relationship between reef disturbance and heatwave impacts depends upon the scale of biological organization. We show that a tropical heatwave of globally unprecedented duration (~1 year) culminated in an 89% loss of hard coral cover. At the community level, losses depended on pre-heatwave community structure, with undisturbed sites, which were dominated by competitive corals, undergoing the greatest losses. In contrast, at the species level, survivorship of individual corals typically declined as local disturbance intensified. Our study reveals both that prolonged heatwaves projected under climate change will still have winners and losers and that local disturbance can impair survival of coral species even under such extreme conditions.
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Affiliation(s)
- Julia K Baum
- Department of Biology, University of Victoria, P.O. Box 1700 Station CSC, Victoria, British Columbia V8W 2Y2, Canada
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kaneohe, HI 96744, USA
| | - Danielle C Claar
- Department of Biology, University of Victoria, P.O. Box 1700 Station CSC, Victoria, British Columbia V8W 2Y2, Canada
- Washington State Department of Natural Resources, MS 47027, Olympia, WA 98504, USA
| | - Kristina L Tietjen
- Department of Biology, University of Victoria, P.O. Box 1700 Station CSC, Victoria, British Columbia V8W 2Y2, Canada
| | - Jennifer M T Magel
- Department of Biology, University of Victoria, P.O. Box 1700 Station CSC, Victoria, British Columbia V8W 2Y2, Canada
- Department of Forest & Conservation Sciences, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Dominique G Maucieri
- Department of Biology, University of Victoria, P.O. Box 1700 Station CSC, Victoria, British Columbia V8W 2Y2, Canada
| | - Kim M Cobb
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
- Institute at Brown University for Environment and Society, Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI 02912, USA
| | - Jamie M McDevitt-Irwin
- Department of Biology, University of Victoria, P.O. Box 1700 Station CSC, Victoria, British Columbia V8W 2Y2, Canada
- Hopkins Marine Station, Stanford University, 120 Ocean View Blvd, Pacific Grove, CA 93950, USA
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19
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Doering T, Maire J, van Oppen MJH, Blackall LL. Advancing coral microbiome manipulation to build long-term climate resilience. MICROBIOLOGY AUSTRALIA 2023. [DOI: 10.1071/ma23009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023] Open
Abstract
Coral reefs house one-third of all marine species and are of high cultural and socioeconomic importance. However, coral reefs are under dire threat from climate change and other anthropogenic stressors. Climate change is causing coral bleaching, the breakdown of the symbiosis between the coral host and its algal symbionts, often resulting in coral mortality and the deterioration of these valuable ecosystems. While it is essential to counteract the root causes of climate change, it remains urgent to develop coral restoration and conservation methods that will buy time for coral reefs. The manipulation of the bacterial microbiome that is associated with corals has been suggested as one intervention to improve coral climate resilience. Early coral microbiome-manipulation studies, which are aimed at enhancing bleaching tolerance, have shown promising results, but the inoculated bacteria did generally not persist within the coral microbiome. Here, we highlight the importance of long-term incorporation of bacterial inocula into the microbiome of target corals, as repeated inoculations will be too costly and not feasible on large reef systems like the Great Barrier Reef. Therefore, coral microbiome-manipulation studies need to prioritise approaches that can provide sustained coral climate resilience.
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20
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Voolstra CR, Peixoto RS, Ferrier-Pagès C. Mitigating the ecological collapse of coral reef ecosystems: Effective strategies to preserve coral reef ecosystems: Effective strategies to preserve coral reef ecosystems. EMBO Rep 2023; 24:e56826. [PMID: 36862379 PMCID: PMC10074092 DOI: 10.15252/embr.202356826] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 01/25/2023] [Accepted: 02/09/2023] [Indexed: 03/03/2023] Open
Abstract
Global warming is decimating coral reefs. We need to implement mitigation and restoration strategies now to prevent coral reefs from disappearing altogether.
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Affiliation(s)
| | - Raquel S Peixoto
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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21
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Zelli E, Simancas-Giraldo SM, Xiang N, Dessì C, Katzer ND, Tilstra A, Wild C. Individual and combined effect of organic eutrophication (DOC) and ocean warming on the ecophysiology of the Octocoral Pinnigorgia flava. PeerJ 2023; 11:e14812. [PMID: 36814959 PMCID: PMC9940650 DOI: 10.7717/peerj.14812] [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: 03/07/2022] [Accepted: 01/06/2023] [Indexed: 02/19/2023] Open
Abstract
Dissolved organic carbon (DOC) enrichment and ocean warming both negatively affect hard corals, but studies on their combined effects on other reef organisms are scarce. Octocorals are likely to become key players in future reef communities, but they are still highly under-investigated with regard to their responses to global and local environmental changes. Thus, we evaluated the individual and combined effects of DOC enrichment (10, 20 and 40 mg L-1 DOC, added as glucose) and warming (stepwise from 26 to 32 °C) on the widespread Indo-Pacific gorgonian Pinnigorgia flava in a 45-day laboratory experiment. Oxygen fluxes (net photosynthesis and respiration), as well as Symbiodiniaceae cell density and coral growth were assessed. Our results highlight a differential ecophysiological response to DOC enrichment and warming as well as their combination. Individual DOC addition did not significantly affect oxygen fluxes nor Symbiodiniaceae cell density and growth, while warming significantly decreased photosynthesis rates and Symbiodiniaceae cell density. When DOC enrichment and warming were combined, no effect on P. flava oxygen fluxes was observed while growth responded to certain DOC conditions depending on the temperature. Our findings indicate that P. flava is insensitive to the individual effect of DOC enrichment, but not to warming and the two stressors combined. This suggests that, if temperature remains below certain thresholds, this gorgonian species may gain a competitive advantage over coral species that are reportedly more affected by DOC eutrophication. However, under the expected increasing temperature scenarios, it is also likely that this octocoral species will be negatively affected, with potential consequences on community structure. This study contributes to our understanding of the conditions that drive phase shift dynamics in coastal coral reef ecosystemds.
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Affiliation(s)
- Edoardo Zelli
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany,School of Science, University of Waikato, Tauranga, New Zealand
| | | | - Nan Xiang
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany,Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Bremerhaven, Germany
| | - Claudia Dessì
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany,Dipartimento di Scienze della Vita e dell’Ambiente, University of Cagliari, Cagliari, Italy
| | - Nadim Daniel Katzer
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany
| | - Arjen Tilstra
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany
| | - Christian Wild
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany
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22
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Haydon TD, Matthews JL, Seymour JR, Raina JB, Seymour JE, Chartrand K, Camp EF, Suggett DJ. Metabolomic signatures of corals thriving across extreme reef habitats reveal strategies of heat stress tolerance. Proc Biol Sci 2023; 290:20221877. [PMID: 36750192 PMCID: PMC9904954 DOI: 10.1098/rspb.2022.1877] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 01/11/2023] [Indexed: 02/09/2023] Open
Abstract
Anthropogenic stressors continue to escalate worldwide, driving unprecedented declines in reef environmental conditions and coral health. One approach to better understand how corals can function in the future is to examine coral populations that thrive within present day naturally extreme habitats. We applied untargeted metabolomics (gas chromatography-mass spectrometry (GC-MS)) to contrast metabolite profiles of Pocillopora acuta colonies from hot, acidic and deoxygenated mangrove environments versus those from adjacent reefs. Under ambient temperatures, P. acuta predominantly associated with endosymbionts of the genera Cladocopium (reef) or Durusdinium (mangrove), exhibiting elevated metabolism in mangrove through energy-generating and biosynthesis pathways compared to reef populations. Under transient heat stress, P. acuta endosymbiont associations were unchanged. Reef corals bleached and exhibited extensive shifts in symbiont metabolic profiles (whereas host metabolite profiles were unchanged). By contrast, mangrove populations did not bleach and solely the host metabolite profiles were altered, including cellular responses in inter-partner signalling, antioxidant capacity and energy storage. Thus mangrove P. acuta populations resist periodically high-temperature exposure via association with thermally tolerant endosymbionts coupled with host metabolic plasticity. Our findings highlight specific metabolites that may be biomarkers of heat tolerance, providing novel insight into adaptive coral resilience to elevated temperatures.
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Affiliation(s)
- Trent D. Haydon
- Center for Genomics and Systems Biology, New York University Abu Dhabi, PO Box 129188, Abu Dhabi, UAE
- Faculty of Science, Climate Change Cluster, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Jennifer L. Matthews
- Faculty of Science, Climate Change Cluster, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Justin R. Seymour
- Faculty of Science, Climate Change Cluster, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Jean-Baptiste Raina
- Faculty of Science, Climate Change Cluster, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Jamie E. Seymour
- Division of Tropical Health and Medicine, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4811, Australia
| | - Kathryn Chartrand
- Centre for tropical Water and Aquatic Ecosystem Research, James Cook University, Cairns, QLD 4811, Australia
| | - Emma F. Camp
- Faculty of Science, Climate Change Cluster, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - David J. Suggett
- Faculty of Science, Climate Change Cluster, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
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23
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Hernández Elizárraga VH, Olguín-López N, Hernández-Matehuala R, Caballero-Pérez J, Ibarra-Alvarado C, Rojas-Molina A. Transcriptomic differences between bleached and unbleached hydrozoan Millepora complanata following the 2015-2016 ENSO in the Mexican Caribbean. PeerJ 2023; 11:e14626. [PMID: 36691486 PMCID: PMC9864129 DOI: 10.7717/peerj.14626] [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: 04/27/2022] [Accepted: 12/02/2022] [Indexed: 01/19/2023] Open
Abstract
The 2015-2016 El Niño-southern oscillation or "ENSO" caused many M. complanata colonies that live in the Mexican Caribbean to experience extensive bleaching. The purpose of this work was to analyze the effect of bleaching on the cellular response of M. complanata, employing a transcriptomic approach with RNA-seq. As expected, bleached specimens contained a significantly lower chlorophyll content than unbleached hydrocorals. The presence of algae of the genera Durusdinium and Cladocopium was only found in tissues of unbleached M. complanata, which could be associated to the greater resistance that these colonies exhibited during bleaching. We found that 299 genes were differentially expressed in M. complanata bleached colonies following the 2015-2016 ENSO in the Mexican Caribbean. The differential expression analysis of bleached M. complanata specimens evidenced enriched terms for functional categories, such as ribosome, RNA polymerase and basal transcription factors, chaperone, oxidoreductase, among others. Our results suggest that the heat-shock response mechanisms displayed by M. complanata include: an up-regulation of endogenous antioxidant defenses; a higher expression of heat stress response genes; up-regulation of transcription-related genes, higher expression of genes associated to transport processes, inter alia. This study constitutes the first differential gene expression analysis of the molecular response of a reef-forming hydrozoan during bleaching.
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Affiliation(s)
| | - Norma Olguín-López
- Posgrado en Ciencias Químico Biológicas, Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, México
| | - Rosalina Hernández-Matehuala
- Posgrado en Ciencias Químico Biológicas, Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, México
| | | | - César Ibarra-Alvarado
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, México
| | - Alejandra Rojas-Molina
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, México
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24
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Alderdice R, Perna G, Cárdenas A, Hume BCC, Wolf M, Kühl M, Pernice M, Suggett DJ, Voolstra CR. Deoxygenation lowers the thermal threshold of coral bleaching. Sci Rep 2022; 12:18273. [PMID: 36316371 PMCID: PMC9622859 DOI: 10.1038/s41598-022-22604-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 10/17/2022] [Indexed: 12/02/2022] Open
Abstract
Exposure to deoxygenation from climate warming and pollution is emerging as a contributing factor of coral bleaching and mortality. However, the combined effects of heating and deoxygenation on bleaching susceptibility remain unknown. Here, we employed short-term thermal stress assays to show that deoxygenated seawater can lower the thermal limit of an Acropora coral by as much as 1 °C or 0.4 °C based on bleaching index scores or dark-acclimated photosynthetic efficiencies, respectively. Using RNA-Seq, we show similar stress responses to heat with and without deoxygenated seawater, both activating putative key genes of the hypoxia-inducible factor response system indicative of cellular hypoxia. We also detect distinct deoxygenation responses, including a disruption of O2-dependent photo-reception/-protection, redox status, and activation of an immune response prior to the onset of bleaching. Thus, corals are even more vulnerable when faced with heat stress in deoxygenated waters. This highlights the need to integrate dissolved O2 measurements into global monitoring programs of coral reefs.
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Affiliation(s)
- Rachel Alderdice
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, 2007, Australia.
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany.
| | - Gabriela Perna
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
| | - Anny Cárdenas
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
| | - Benjamin C C Hume
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
| | - Martin Wolf
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
| | - Michael Kühl
- Marine Biology Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, 3000, Helsingør, Denmark
| | - Mathieu Pernice
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - David J Suggett
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, 2007, Australia
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25
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Rich WA, Carvalho S, Berumen ML. Coral bleaching due to cold stress on a central Red Sea reef flat. Ecol Evol 2022; 12:e9450. [PMID: 36284520 PMCID: PMC9587464 DOI: 10.1002/ece3.9450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/06/2022] [Accepted: 10/10/2022] [Indexed: 12/03/2022] Open
Abstract
Ocean warming is leading to more frequent coral bleaching events. However, cold stress can also induce bleaching in corals. Here, we report observations of a boreal winter bleaching event in January 2020 in the central Red Sea, mainly within a population of the branching coral Stylophora pistillata on an offshore reef flat. Sea surface temperatures (SSTs) rarely fall below 24°C in this region, but data loggers deployed on several nearby reef flats recorded overnight seawater temperatures as low as 18°C just 3 days before the observations. The low temperatures coincided with an extremely low tide and cool air temperatures, likely resulting in the aerial exposure of the corals during the night time low‐tide event. The risk of aerial exposure is rare in winter months, as the Red Sea exhibits seasonal fluctuations in sea level with winter values typically 0.3–0.4 m higher than in summer. These observations are notable for a region typically characterized as a high‐temperature sea, and highlight the need for long‐term monitoring programs as this rare event may have gone unnoticed.
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Affiliation(s)
- Walter A. Rich
- Red Sea Research CenterKing Abdullah University of Science and TechnologyThuwalSaudi Arabia
| | - Susana Carvalho
- Red Sea Research CenterKing Abdullah University of Science and TechnologyThuwalSaudi Arabia
| | - Michael L. Berumen
- Red Sea Research CenterKing Abdullah University of Science and TechnologyThuwalSaudi Arabia
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26
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Nielsen JJV, Matthews G, Frith KR, Harrison HB, Marzonie MR, Slaughter KL, Suggett DJ, Bay LK. Experimental considerations of acute heat stress assays to quantify coral thermal tolerance. Sci Rep 2022; 12:16831. [PMID: 36207307 PMCID: PMC9546840 DOI: 10.1038/s41598-022-20138-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 09/08/2022] [Indexed: 11/23/2022] Open
Abstract
Understanding the distribution and abundance of heat tolerant corals across seascapes is imperative for predicting responses to climate change and to support novel management actions. Thermal tolerance is variable in corals and intrinsic and extrinsic drivers of tolerance are not well understood. Traditional experimental evaluations of coral heat and bleaching tolerance typically involve ramp-and-hold experiments run across days to weeks within aquarium facilities with limits to colony replication. Field-based acute heat stress assays have emerged as an alternative experimental approach to rapidly quantify heat tolerance in many samples yet the role of key methodological considerations on the stress response measured remains unresolved. Here, we quantify the effects of coral fragment size, sampling time point, and physiological measures on the acute heat stress response in adult corals. The effect of fragment size differed between species (Acropora tenuis and Pocillopora damicornis). Most physiological parameters measured here declined over time (tissue colour, chlorophyll-a and protein content) from the onset of heating, with the exception of maximum photosynthetic efficiency (Fv/Fm) which was surprisingly stable over this time scale. Based on our experiments, we identified photosynthetic efficiency, tissue colour change, and host-specific assays such as catalase activity as key physiological measures for rapid quantification of thermal tolerance. We recommend that future applications of acute heat stress assays include larger fragments (> 9 cm2) where possible and sample between 10 and 24 h after the end of heat stress. A validated high-throughput experimental approach combined with cost-effective genomic and physiological measurements underpins the development of markers and maps of heat tolerance across seascapes and ocean warming scenarios.
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Affiliation(s)
- J J V Nielsen
- College of Public Health, Medicine, and Veterinary Sciences, James Cook University, Townsville, QLD, 4811, Australia. .,Australian Institute of Marine Science, PMB #3, Townsville, MC, QLD, 4810, Australia. .,AIMS@JCU, Australian Institute of Marine Science, James Cook University, Townsville, QLD, 4811, Australia.
| | - G Matthews
- Wellcome Centre for Human Genetics, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - K R Frith
- Australian Institute of Marine Science, PMB #3, Townsville, MC, QLD, 4810, Australia.,Centre for Resilience in Environment, Water and Waste, Geography, College of Life and Environmental Sciences, University of Exeter, Amory Building, Exeter, EX4 4RJ, Devon, UK
| | - H B Harrison
- Australian Institute of Marine Science, PMB #3, Townsville, MC, QLD, 4810, Australia.,Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, 4811, Australia
| | - M R Marzonie
- Australian Institute of Marine Science, PMB #3, Townsville, MC, QLD, 4810, Australia.,AIMS@JCU, Australian Institute of Marine Science, James Cook University, Townsville, QLD, 4811, Australia.,Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, 4811, Australia
| | - K L Slaughter
- AIMS@JCU, Australian Institute of Marine Science, James Cook University, Townsville, QLD, 4811, Australia.,College of Science and Engineering, James Cook University, Townsville, QLD, 4811, Australia
| | - D J Suggett
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - L K Bay
- Australian Institute of Marine Science, PMB #3, Townsville, MC, QLD, 4810, Australia
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27
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Johnson JV, Exton DA, Dick JTA, Oakley J, Jompa J, Pincheira-Donoso D. The relative influence of sea surface temperature anomalies on the benthic composition of an Indo-Pacific and Caribbean coral reef over the last decade. Ecol Evol 2022; 12:ECE39263. [PMID: 36091340 PMCID: PMC9448965 DOI: 10.1002/ece3.9263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 08/08/2022] [Accepted: 08/14/2022] [Indexed: 11/06/2022] Open
Abstract
Rising ocean temperatures are the primary driver of coral reef declines throughout the tropics. Such declines include reductions in coral cover that facilitate the monopolization of the benthos by other taxa such as macroalgae, resulting in reduced habitat complexity and biodiversity. Long-term monitoring projects present rare opportunities to assess how sea surface temperature anomalies (SSTAs) influence changes in the benthic composition of coral reefs across distinct locations. Here, using extensively monitored coral reef sites from Honduras (in the Caribbean Sea), and from the Wakatobi National Park located in the center of the coral triangle of Indonesia, we assess the impact of global warming on coral reef benthic compositions over the period 2012-2019. Bayesian generalized linear mixed effect models revealed increases in the sponge, and hard coral coverage through time, while rubble coverage decreased at the Indonesia location. Conversely, the effect of SSTAs did not predict any changes in benthic coverage. At the Honduras location, algae and soft coral coverage increased through time, while hard coral and rock coverage were decreasing. The effects of SSTA at the Honduras location included increased rock coverage, but reduced sponge coverage, indicating disparate responses between both systems under SSTAs. However, redundancy analyses showed intralocation site variability explained the majority of variance in benthic composition over the course of the study period. Our findings show that SSTAs have differentially influenced the benthic composition between the Honduras and the Indonesian coral reefs surveyed in this study. However, the large intralocation variance that explains the benthic composition at both locations indicates that localized processes have a predominant role in explaining benthic composition over the last decade. The sustained monitoring effort is critical for understanding how these reefs will change in their composition as global temperatures continue to rise through the Anthropocene.
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Affiliation(s)
- Jack V Johnson
- Macrobiodiversity Lab, School of Biological Sciences Queen's University Belfast Belfast UK.,Operation Wallacea Spilsby UK
| | | | - Jaimie T A Dick
- Institute for Global Food Security, School of Biological Sciences Queen's University Belfast Belfast UK
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28
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Adaptive Responses of the Sea Anemone Heteractis crispa to the Interaction of Acidification and Global Warming. Animals (Basel) 2022; 12:ani12172259. [PMID: 36077978 PMCID: PMC9454579 DOI: 10.3390/ani12172259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 08/26/2022] [Accepted: 08/27/2022] [Indexed: 11/16/2022] Open
Abstract
Ocean acidification and warming are two of the most important threats to the existence of marine organisms and are predicted to co-occur in oceans. The present work evaluated the effects of acidification (AC: 24 ± 0.1 °C and 900 μatm CO2), warming (WC: 30 ± 0.1 °C and 450 μatm CO2), and their combination (CC: 30 ± 0.1 °C and 900 μatm CO2) on the sea anemone, Heteractis crispa, from the aspects of photosynthetic apparatus (maximum quantum yield of photosystem II (PS II), chlorophyll level, and Symbiodiniaceae density) and sterol metabolism (cholesterol content and total sterol content). In a 15-day experiment, acidification alone had no apparent effect on the photosynthetic apparatus, but did affect sterol levels. Upregulation of their chlorophyll level is an important strategy for symbionts to adapt to high partial pressure of CO2 (pCO2). However, after warming stress, the benefits of high pCO2 had little effect on stress tolerance in H. crispa. Indeed, thermal stress was the dominant driver of the deteriorating health of H. crispa. Cholesterol and total sterol contents were significantly affected by all three stress conditions, although there was no significant change in the AC group on day 3. Thus, cholesterol or sterol levels could be used as important indicators to evaluate the impact of climate change on cnidarians. Our findings suggest that H. crispa might be relatively insensitive to the impact of ocean acidification, whereas increased temperature in the future ocean might impair viability of H. crispa.
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29
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Effects of Hypoxia on Coral Photobiology and Oxidative Stress. BIOLOGY 2022; 11:biology11071068. [PMID: 36101446 PMCID: PMC9312924 DOI: 10.3390/biology11071068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 06/21/2022] [Accepted: 07/08/2022] [Indexed: 11/16/2022]
Abstract
Global ocean oxygen (O2) content is decreasing as climate change drives declines in oxygen solubility, strengthened stratification of seawater masses, increased biological oxygen consumption and coastal eutrophication. Studies on the biological effects of nocturnal decreased oxygen concentrations (hypoxia) on coral reefs are very scarce. Coral reefs are fundamental for supporting one quarter of all marine species and essential for around 275 million people worldwide. This study investigates acute physiological and photobiological responses of a scleractinian coral (Acropora spp.) to overnight hypoxic conditions (<2 mg/L of O2). Bleaching was not detected, and visual and physical aspects of corals remained unchanged under hypoxic conditions. Most photobiological-related parameters also did not show significant changes between treatments. In addition to this, no significant differences between treatments were observed in the pigment composition. However, hypoxic conditions induced a significant decrease in coral de-epoxidation state of the xanthophyll cycle pigments and increase in DNA damage. Although the present findings suggest that Acropora spp. is resilient to some extent to short-term daily oxygen oscillations, long-term exposure to hypoxia, as predicted to occur with climate change, may still have deleterious effects on corals.
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30
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van Woesik R, Shlesinger T, Grottoli AG, Toonen RJ, Vega Thurber R, Warner ME, Marie Hulver A, Chapron L, McLachlan RH, Albright R, Crandall E, DeCarlo TM, Donovan MK, Eirin‐Lopez J, Harrison HB, Heron SF, Huang D, Humanes A, Krueger T, Madin JS, Manzello D, McManus LC, Matz M, Muller EM, Rodriguez‐Lanetty M, Vega‐Rodriguez M, Voolstra CR, Zaneveld J. Coral-bleaching responses to climate change across biological scales. GLOBAL CHANGE BIOLOGY 2022; 28:4229-4250. [PMID: 35475552 PMCID: PMC9545801 DOI: 10.1111/gcb.16192] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 05/26/2023]
Abstract
The global impacts of climate change are evident in every marine ecosystem. On coral reefs, mass coral bleaching and mortality have emerged as ubiquitous responses to ocean warming, yet one of the greatest challenges of this epiphenomenon is linking information across scientific disciplines and spatial and temporal scales. Here we review some of the seminal and recent coral-bleaching discoveries from an ecological, physiological, and molecular perspective. We also evaluate which data and processes can improve predictive models and provide a conceptual framework that integrates measurements across biological scales. Taking an integrative approach across biological and spatial scales, using for example hierarchical models to estimate major coral-reef processes, will not only rapidly advance coral-reef science but will also provide necessary information to guide decision-making and conservation efforts. To conserve reefs, we encourage implementing mesoscale sanctuaries (thousands of km2 ) that transcend national boundaries. Such networks of protected reefs will provide reef connectivity, through larval dispersal that transverse thermal environments, and genotypic repositories that may become essential units of selection for environmentally diverse locations. Together, multinational networks may be the best chance corals have to persist through climate change, while humanity struggles to reduce emissions of greenhouse gases to net zero.
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Affiliation(s)
- Robert van Woesik
- Institute for Global EcologyFlorida Institute of TechnologyMelbourneFloridaUSA
| | - Tom Shlesinger
- Institute for Global EcologyFlorida Institute of TechnologyMelbourneFloridaUSA
| | | | - Rob J. Toonen
- Hawai'i Institute of Marine Biology, KāneʻoheUniversity of Hawaiʻi at MānoaHonoluluHawaiiUSA
| | | | - Mark E. Warner
- School of Marine Science and PolicyUniversity of DelawareLewesDelawareUSA
| | - Ann Marie Hulver
- School of Earth SciencesThe Ohio State UniversityColumbusOhioUSA
| | - Leila Chapron
- School of Earth SciencesThe Ohio State UniversityColumbusOhioUSA
| | - Rowan H. McLachlan
- School of Earth SciencesThe Ohio State UniversityColumbusOhioUSA
- Department of MicrobiologyOregon State UniversityCorvallisOregonUSA
| | | | - Eric Crandall
- Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | | | - Mary K. Donovan
- Center for Global Discovery and Conservation Science and School of Geographical Sciences and Urban PlanningArizona State UniversityTempeArizonaUSA
| | - Jose Eirin‐Lopez
- Institute of EnvironmentFlorida International UniversityMiamiFloridaUSA
| | - Hugo B. Harrison
- ARC Centre of Excellence for Coral Reef StudiesJames Cook UniversityTownsvilleQueenslandAustralia
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
| | - Scott F. Heron
- ARC Centre of Excellence for Coral Reef StudiesJames Cook UniversityTownsvilleQueenslandAustralia
- Physics and Marine Geophysical LaboratoryJames Cook UniversityTownsvilleQueenslandAustralia
| | - Danwei Huang
- Department of Biological SciencesNational University of SingaporeSingapore
| | - Adriana Humanes
- School of Natural and Environmental SciencesNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Thomas Krueger
- Department of BiochemistryUniversity of CambridgeCambridgeUnited Kingdom
| | - Joshua S. Madin
- Hawai'i Institute of Marine Biology, KāneʻoheUniversity of Hawaiʻi at MānoaHonoluluHawaiiUSA
| | - Derek Manzello
- Center for Satellite Applications and ResearchSatellite Oceanography & Climate DivisionNational Oceanic and Atmospheric AdministrationCollege ParkMarylandUSA
| | - Lisa C. McManus
- Hawai'i Institute of Marine Biology, KāneʻoheUniversity of Hawaiʻi at MānoaHonoluluHawaiiUSA
| | - Mikhail Matz
- Department of Integrative BiologyUniversity of Texas at AustinAustinTexasUSA
| | | | | | | | | | - Jesse Zaneveld
- Division of Biological SciencesUniversity of WashingtonBothellWashingtonUSA
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31
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Bednarz VN, Choyke S, Marangoni LFB, Otto EI, Béraud E, Metian M, Tolosa I, Ferrier-Pagès C. Acute exposure to perfluorooctane sulfonate exacerbates heat-induced oxidative stress in a tropical coral species. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 302:119054. [PMID: 35219792 DOI: 10.1016/j.envpol.2022.119054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 02/02/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
Perfluorooctane sulfonate (PFOS) is among the most commonly per- and poly-fluoroalkyl substances (PFAS) found in environmental samples. Nevertheless, the effect of this legacy persistent organic contaminant has never been investigated on corals to date. Corals are the keystone organisms of coral reef ecosystems and sensitive to rising ocean temperatures, but it is not understood how the combination of elevated temperature and PFOS exposure will affect them. Therefore, the aims of the present study were (1) to evaluate the time-dependent bioconcentration and depuration of PFOS in the scleractinian coral Stylophora pistillata using a range of PFOS exposure concentrations, and (2) to assess the individual and combined effects of PFOS exposure and elevated seawater temperature on key physiological parameters of the corals. Our results show that the coral S. pistillata rapidly bioconcentrates PFOS from the seawater and eliminates it 14 days after ceasing the exposure. We also observed an antagonistic effect between elevated temperature and PFOS exposure. Indeed, a significantly reduced PFOS bioconcentration was observed at high temperature, likely due to a loss of symbionts and a higher removal of mucus compared to ambient temperature. Finally, concentrations of PFOS consistent with ranges observed in surface waters were non-lethal to corals, in the absence of other stressors. However, PFOS increased lipid peroxidation in coral tissue, which is an indicator of oxidative stress and enhanced the thermal stress-induced impairment of coral physiology. This study provides valuable insights into the combined effects of PFOS exposure and ocean warming for coral's physiology. PFOS is usually the most prevalent but not the only PFAS defected in reef waters, and thus it will be also important to monitor PFAS mixture concentrations in the oceans and to study their combined effects on aquatic wildlife.
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Affiliation(s)
- V N Bednarz
- Centre Scientifique de Monaco, Marine Biology Department, 8 Quai Antoine 1er, MC-98000, Monaco, Monaco.
| | - S Choyke
- International Atomic Energy Agency, Environment Laboratories, 4a Quai Antoine 1er, MC-98000, Monaco, Monaco
| | - L F B Marangoni
- Centre Scientifique de Monaco, Marine Biology Department, 8 Quai Antoine 1er, MC-98000, Monaco, Monaco; Smithsonian Tropical Research Institute, Smithsonian Institution, Ciudad de Panama, 0843-03092, Panama
| | - E I Otto
- Palau International Coral Reef Center, 1 M-Dock Road, P.O. Box 7086, Koror, 96940, Palau
| | - E Béraud
- Centre Scientifique de Monaco, Marine Biology Department, 8 Quai Antoine 1er, MC-98000, Monaco, Monaco
| | - M Metian
- International Atomic Energy Agency, Environment Laboratories, 4a Quai Antoine 1er, MC-98000, Monaco, Monaco
| | - I Tolosa
- International Atomic Energy Agency, Environment Laboratories, 4a Quai Antoine 1er, MC-98000, Monaco, Monaco
| | - C Ferrier-Pagès
- Centre Scientifique de Monaco, Marine Biology Department, 8 Quai Antoine 1er, MC-98000, Monaco, Monaco
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Steinberg RK, Ainsworth TD, Moriarty T, Bednarek T, Dafforn KA, Johnston EL. Bleaching Susceptibility and Resistance of Octocorals and Anemones at the World's Southern-Most Coral Reef. Front Physiol 2022; 13:804193. [PMID: 35665222 PMCID: PMC9161773 DOI: 10.3389/fphys.2022.804193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/29/2022] [Indexed: 11/16/2022] Open
Abstract
Coral reefs are amongst the most biodiverse ecosystems on earth, and while stony corals create the foundational complexity of these ecosystems, octocorals and anemones contribute significantly to their biodiversity and function. Like stony corals, many octocorals contain Symbiodiniaceae endosymbionts and can bleach when temperatures exceed the species' upper thermal limit. Here, we report octocoral bleaching susceptibility and resistance within the subtropical Lord Howe Island coral reef ecosystem during and after marine heatwaves in 2019. Octocoral and anemone surveys were conducted at multiple reef locations within the Lord Howe Island lagoon during, immediately after, and 7 months after the heatwaves. One octocoral species, Cladiella sp. 1, experienced bleaching and mortality, with some bleached colonies detaching from the reef structure during the heatwave (presumed dead). Those that remained attached to the benthos survived the event and recovered endosymbionts within 7 months of bleaching. Cladiella sp. 1 Symbiodiniaceae density (in cells per µg protein), chlorophyll a and c 2 per µg protein, and photosynthetic efficiency were significantly lower in bleached colonies compared to unbleached colonies, while chlorophyll a and c 2 per symbiont were higher. Interestingly, no other symbiotic octocoral species of the Lord Howe Island lagoonal reef bleached. Unbleached Xenia cf crassa colonies had higher Symbiodiniaceae and chlorophyll densities during the marine heatwave compared to other monitoring intervals, while Cladiella sp. 2 densities did not change substantially through time. Previous work on octocoral bleaching has focused primarily on gorgonian octocorals, while this study provides insight into bleaching variability in other octocoral groups. The study also provides further evidence that octocorals may be generally more resistant to bleaching than stony corals in many, but not all, reef ecosystems. Responses to marine heating events vary and should be assessed on a species by species basis.
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Affiliation(s)
- Rosemary K Steinberg
- Evolution and Ecology Research Centre and Centre for Marine Science and Innovation, School of Biological, Earth, and Environmental Sciences, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
- Sydney Institute of Marine Science, Mosman, NSW, Australia
| | - Tracy D Ainsworth
- Evolution and Ecology Research Centre and Centre for Marine Science and Innovation, School of Biological, Earth, and Environmental Sciences, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
| | - Tess Moriarty
- School of Environmental and Life Sciences, The University of Newcastle, Ourimbah, NSW, Australia
| | - Teresa Bednarek
- Evolution and Ecology Research Centre and Centre for Marine Science and Innovation, School of Biological, Earth, and Environmental Sciences, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
- RUHR Universtad Bouchum, Bouchum, Germany
| | | | - Emma L Johnston
- Evolution and Ecology Research Centre and Centre for Marine Science and Innovation, School of Biological, Earth, and Environmental Sciences, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
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33
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Adam AAS, Thomas L, Underwood J, Gilmour J, Richards ZT. Population connectivity and genetic offset in the spawning coral Acropora digitifera in Western Australia. Mol Ecol 2022; 31:3533-3547. [PMID: 35567512 PMCID: PMC9328316 DOI: 10.1111/mec.16498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 04/01/2022] [Accepted: 04/11/2022] [Indexed: 11/28/2022]
Abstract
Anthropogenic climate change has caused widespread loss of species biodiversity and ecosystem productivity across the globe, particularly on tropical coral reefs. Predicting the future vulnerability of reef-building corals, the foundation species of coral reef ecosystems, is crucial for cost-effective conservation planning in the Anthropocene. In this study, we combine regional population genetic connectivity and seascape analyses to explore patterns of genetic offset (the mismatch of gene-environmental associations under future climate conditions) in Acropora digitifera across 12 degrees of latitude in Western Australia. Our data revealed a pattern of restricted gene flow and limited genetic connectivity among geographically distant reef systems. Environmental association analyses identified a suite of loci strongly associated with the regional temperature variation. These loci helped forecast future genetic offset in gradient forest and generalised dissimilarity models. These analyses predicted pronounced differences in the response of different reef systems in Western Australia to rising temperatures. Under the most optimistic future warming scenario (RCP 2.6), we predicted a general pattern of increasing genetic offset with latitude. Under the extreme climate scenario (RCP 8.5 in 2090-2100), coral populations at the Ningaloo World Heritage Area were predicted to experience a higher mismatch between current allele frequencies and those required to cope with local environmental change, compared to populations in the inshore Kimberley region. The study suggests complex and spatially heterogeneous patterns of climate-change vulnerability in coral populations across Western Australia, reinforcing the notion that regionally tailored conservation efforts will be most effective at managing coral reef resilience into the future.
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Affiliation(s)
- Arne A S Adam
- Coral Conservation and Research Group, Trace and Environmental DNA Laboratory, School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia.,Australian Institute of Marine Science, IOMRC, The University of Western Australia, Crawley, Western Australia
| | - Luke Thomas
- Australian Institute of Marine Science, IOMRC, The University of Western Australia, Crawley, Western Australia.,The UWA Oceans Institute, Oceans Graduate School, The University of Western Australia, Crawley, Western Australia
| | - Jim Underwood
- Australian Institute of Marine Science, IOMRC, The University of Western Australia, Crawley, Western Australia
| | - James Gilmour
- Australian Institute of Marine Science, IOMRC, The University of Western Australia, Crawley, Western Australia
| | - Zoe T Richards
- Coral Conservation and Research Group, Trace and Environmental DNA Laboratory, School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia.,Collections and Research, Western Australian Museum, Welshpool, Western Australia
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Hughes DJ, Raina JB, Nielsen DA, Suggett DJ, Kühl M. Disentangling compartment functions in sessile marine invertebrates. Trends Ecol Evol 2022; 37:740-748. [PMID: 35570130 DOI: 10.1016/j.tree.2022.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 04/09/2022] [Accepted: 04/13/2022] [Indexed: 01/01/2023]
Abstract
Sessile invertebrates are frequently sampled and processed whole for downstream analyses. However, their apparent structural simplicity is deceptive as these organisms often harbour discrete compartments. These compartments have physicochemical conditions that differ markedly from neighbouring tissues, and that have likely evolved to support specific functions. Here, we argue that such compartments should be specifically targeted when characterising sessile invertebrate biology and we use the coral gastrovascular cavity to support our argument. This complex compartment displays steep and dynamic chemical gradients, harbours distinct microorganisms, and presumably plays a key role in coral biology. Disentangling the functions played by (and amongst) compartments will likely provide transformative insight into the biology of sessile invertebrates and their future under environmental change.
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Affiliation(s)
- David J Hughes
- University of Technology Sydney, Climate Change Cluster, Ultimo, NSW 2007, Australia.
| | - Jean-Baptiste Raina
- University of Technology Sydney, Climate Change Cluster, Ultimo, NSW 2007, Australia.
| | - Daniel A Nielsen
- University of Technology Sydney, School of Life Sciences, Ultimo, NSW 2007, Australia
| | - David J Suggett
- University of Technology Sydney, Climate Change Cluster, Ultimo, NSW 2007, Australia
| | - Michael Kühl
- University of Technology Sydney, Climate Change Cluster, Ultimo, NSW 2007, Australia; Marine Biology Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, DK 3000 Helsingør, Denmark.
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35
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Proteome metabolome and transcriptome data for three Symbiodiniaceae under ambient and heat stress conditions. Sci Data 2022; 9:153. [PMID: 35383179 PMCID: PMC8983644 DOI: 10.1038/s41597-022-01258-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 03/14/2022] [Indexed: 12/12/2022] Open
Abstract
The Symbiodiniaceae are a taxonomically and functionally diverse family of marine dinoflagellates. Their symbiotic relationship with invertebrates such as scleractinian corals has made them the focus of decades of research to resolve the underlying biology regulating their sensitivity to stressors, particularly thermal stress. Research to-date suggests that Symbiodiniaceae stress sensitivity is governed by a complex interplay between phylogenetic dependent and independent traits (diversity of characteristics of a species). Consequently, there is a need for datasets that simultaneously broadly resolve molecular and physiological processes under stressed and non-stressed conditions. Therefore, we provide a dataset simultaneously generating transcriptome, metabolome, and proteome data for three ecologically important Symbiodiniaceae isolates under nutrient replete growth conditions and two temperature treatments (ca. 26 °C and 32 °C). Elevated sea surface temperature is primarily responsible for coral bleaching events that occur when the coral-Symbiodiniaceae relationship has been disrupted. Symbiodiniaceae can strongly influence their host's response to thermal stress and consequently it is necessary to resolve drivers of Symbiodiniaceae heat stress tolerance. We anticipate these datasets to expand our understanding on the key genotypic and functional properties that influence the sensitivities of Symbiodiniaceae to thermal stress.
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36
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Blanckaert ACA, Omanović D, Fine M, Grover R, Ferrier-Pagès C. Desert dust deposition supplies essential bioelements to Red Sea corals. GLOBAL CHANGE BIOLOGY 2022; 28:2341-2359. [PMID: 34981609 DOI: 10.1111/gcb.16074] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 12/14/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Climate change-related increase in seawater temperature has become a leading cause of coral bleaching and mortality. However, corals from the northern Red Sea show high thermal tolerance and no recorded massive bleaching event. This specific region is frequently subjected to intense dust storms, coming from the surrounding arid deserts, which are expected to increase in frequency and intensity in the future. The aerial dust deposition supplies essential bioelements to the water column. Here, we investigated the effect of dust deposition on the physiology of a Red Sea coral, Stylophora pistillata. We measured the modifications in coral and Symbiodiniaceae metallome (cellular metal content), as well as the changes in photosynthesis and oxidative stress status of colonies exposed during few weeks to dust deposition. Our results show that 1 mg L-1 of dust supplied nanomolar amounts of nitrate and other essential bioelements, such as iron, manganese, zinc and copper, rapidly assimilated by the symbionts. At 25°C, metal bioaccumulation enhanced the chlorophyll concentration and photosynthesis of dust-exposed corals compared to control corals. These results suggest that primary production was limited by metal availability in seawater. A 5°C increase in seawater temperature enhanced iron assimilation in both control and dust-enriched corals. Temperature rise increased the photosynthesis of control corals only, dust-exposed ones having already reached maximal photosynthesis rates at 25°C. Finally, we observed a combined effect of temperature and bioelement concentration on the assimilation of molybdenum, cadmium, manganese and copper, which were in higher concentrations in symbionts of dust-exposed corals maintained at 30°C. All together these observations highlight the importance of dust deposition in the supply of essential bioelements, such as iron, to corals and its role in sustaining coral productivity in Red Sea reefs.
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Affiliation(s)
- Alice C A Blanckaert
- Centre Scientifique de Monaco, Coral Ecophysiology Team, Monaco, Monaco
- Sorbonne Université, Collège Doctoral, Paris, France
| | - Dario Omanović
- Center for Marine and Environmental Research, Ruđer Bošković Institute, Zagreb, Croatia
| | - Maoz Fine
- The Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
- The Interuniversity Institute for Marine Science in Eilat, Eilat, Israel
| | - Renaud Grover
- Centre Scientifique de Monaco, Coral Ecophysiology Team, Monaco, Monaco
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37
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Maire J, Buerger P, Chan WY, Deore P, Dungan AM, Nitschke MR, van Oppen MJH. Effects of Ocean Warming on the Underexplored Members of the Coral Microbiome. Integr Comp Biol 2022; 62:1700-1709. [PMID: 35259253 PMCID: PMC9801979 DOI: 10.1093/icb/icac005] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 03/01/2022] [Accepted: 03/05/2022] [Indexed: 01/05/2023] Open
Abstract
The climate crisis is one of the most significant threats to marine ecosystems. It is leading to severe increases in sea surface temperatures and in the frequency and magnitude of marine heatwaves. These changing conditions are directly impacting coral reef ecosystems, which are among the most biodiverse ecosystems on Earth. Coral-associated symbionts are particularly affected because summer heatwaves cause coral bleaching-the loss of endosymbiotic microalgae (Symbiodiniaceae) from coral tissues, leading to coral starvation and death. Coral-associated Symbiodiniaceae and bacteria have been extensively studied in the context of climate change, especially in terms of community diversity and dynamics. However, data on other microorganisms and their response to climate change are scarce. Here, we review current knowledge on how increasing temperatures affect understudied coral-associated microorganisms such as archaea, fungi, viruses, and protists other than Symbiodiniaceae, as well as microbe-microbe interactions. We show that the coral-microbe symbiosis equilibrium is at risk under current and predicted future climate change and argue that coral reef conservation initiatives should include microbe-focused approaches.
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Affiliation(s)
| | - Patrick Buerger
- School of BioSciences, University of Melbourne, Parkville, VIC 3010, Australia,Applied BioSciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Wing Yan Chan
- School of BioSciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - Pranali Deore
- School of BioSciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - Ashley M Dungan
- School of BioSciences, University of Melbourne, Parkville, VIC 3010, Australia
| | | | - Madeleine J H van Oppen
- School of BioSciences, University of Melbourne, Parkville, VIC 3010, Australia,Australian Institute of Marine Science, Townsville, QLD 4810, Australia
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38
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Kaposi K, Courtney R, Seymour J. Implications of bleaching on cnidarian venom ecology. Toxicon X 2022; 13:100094. [PMID: 35146416 PMCID: PMC8819380 DOI: 10.1016/j.toxcx.2022.100094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/14/2022] [Accepted: 01/23/2022] [Indexed: 11/03/2022] Open
Abstract
Cnidarian bleaching research often focuses on the effects on a cnidarian's physiological health and fitness, whilst little focus has been towards the impacts of these events on their venom ecology. Given the importance of a cnidarian's venom to their survival and the increasing threat of bleaching events, it is important to understand the effects that this threat may have on this important aspect of their ecology as it may have unforeseen impacts on their ability to catch prey and defend themselves. This review aims to explore evidence that suggests that bleaching may impact on each of the key aspects of a cnidarians' venom ecology: cnidae, venom composition, and venom toxicity. Additionally, the resulting energy deficit, compensatory heterotrophic feeding, and increased defensive measures have been highlighted as possible ecological factors driving these changes. Suggestions are also made to guide the success of research in this field into the future, specifically in regards to selecting a study organism, the importance of accurate symbiont and cnidae identification, use of appropriate bleaching methods, determination of bleaching, and animal handling. Ultimately, this review highlights a significant and important gap in our knowledge into how cnidarians are, and will, continue to be impacted by bleaching stress. Information on the effects of bleaching on cnidarian venom ecology is limited. There is evidence to suggest nematocysts, venom composition and venom toxicity may each be impacted by bleaching. Bleaching may result in depleted energy, increased heterotrophy and/or the need for stronger defensive strategies. To fully understand how cnidarians may be impacted by bleaching stress further research in this field is needed. Future studies should consider the model organism and methodologies, thereby minimising indirect confounding effects.
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Dal Pizzol JL, Marques JA, da Silva Fonseca J, Costa PG, Bianchini A. Metal accumulation induces oxidative stress and alters carbonic anhydrase activity in corals and symbionts from the largest reef complex in the South Atlantic ocean. CHEMOSPHERE 2022; 290:133216. [PMID: 34896171 DOI: 10.1016/j.chemosphere.2021.133216] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 12/04/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
We evaluated the influence of metal accumulation on the oxidative status [lipid peroxidation (LPO) and total antioxidant capacity (TAC)] and carbonic anhydrase (CA) activity in host and symbionts of the coral Mussismilia harttii and the hydrocoral Millepora alcicornis collected in Abrolhos Reef Banks (Northeast Brazil), potentially impacted by a major mine dam rupture. Considering metal levels measured in reefs worldwide, Abrolhos corals had higher Fe and Mn levels than expected for preserved offshore reefs. Increasing concentrations of arsenic (As), chromium (Cr) and manganese (Mn) drove inhibition of CA and increased oxidative damage in the hydrocoral M. alcicornis. The impairment of enzymatic activity in the symbiotic algae of M. alcicornis may be related to the oxidative stress condition. The hydrocoral M. alcicornis was more affected by metals than the coral M. harttii, which did not show the expected CA inhibition after metal exposure. Our results suggest that CA activity can be applied as a complementary biomarker to evaluate the physiological impacts of environmental metal contamination in reefs. Also, the metal levels and biochemical biomarkers reported in the present study may provide reference data to monitor the health of reefs impacted by a relevant dam rupture.
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Affiliation(s)
- Juliana Lemos Dal Pizzol
- Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96.203-900, Rio Grande, RS, Brazil.
| | - Joseane Aparecida Marques
- Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96.203-900, Rio Grande, RS, Brazil
| | - Juliana da Silva Fonseca
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96.203-900, Rio Grande, RS, Brazil
| | - Patrícia Gomes Costa
- Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96.203-900, Rio Grande, RS, Brazil
| | - Adalto Bianchini
- Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96.203-900, Rio Grande, RS, Brazil; Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Avenida Itália Km 8, Campus Carreiros, 96.203-900, Rio Grande, RS, Brazil
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Cotinat P, Fricano C, Toullec G, Röttinger E, Barnay-Verdier S, Furla P. Intrinsically High Capacity of Animal Cells From a Symbiotic Cnidarian to Deal With Pro-Oxidative Conditions. Front Physiol 2022; 13:819111. [PMID: 35222085 PMCID: PMC8867213 DOI: 10.3389/fphys.2022.819111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 01/10/2022] [Indexed: 11/21/2022] Open
Abstract
The cnidarian-dinoflagellate symbiosis is a mutualistic intracellular association based on the photosynthetic activity of the endosymbiont. This relationship involves significant constraints and requires co-evolution processes, such as an extensive capacity of the holobiont to counteract pro-oxidative conditions induced by hyperoxia generated during photosynthesis. In this study, we analyzed the capacity of Anemonia viridis cells to deal with pro-oxidative conditions by in vivo and in vitro approaches. Whole specimens and animal primary cell cultures were submitted to 200 and 500 μM of H2O2 during 7 days. Then, we monitored global health parameters (symbiotic state, viability, and cell growth) and stress biomarkers (global antioxidant capacity, oxidative protein damages, and protein ubiquitination). In animal primary cell cultures, the intracellular reactive oxygen species (ROS) levels were also evaluated under H2O2 treatments. At the whole organism scale, both H2O2 concentrations didn’t affect the survival and animal tissues exhibited a high resistance to H2O2 treatments. Moreover, no bleaching has been observed, even at high H2O2 concentration and after long exposure (7 days). Although, the community has suggested the role of ROS as the cause of bleaching, our results indicating the absence of bleaching under high H2O2 concentration may exculpate this specific ROS from being involved in the molecular processes inducing bleaching. However, counterintuitively, the symbiont compartment appeared sensitive to an H2O2 burst as it displayed oxidative protein damages, despite an enhancement of antioxidant capacity. The in vitro assays allowed highlighting an intrinsic high capacity of isolated animal cells to deal with pro-oxidative conditions, although we observed differences on tolerance between H2O2 treatments. The 200 μM H2O2 concentration appeared to correspond to the tolerance threshold of animal cells. Indeed, no disequilibrium on redox state was observed and only a cell growth decrease was measured. Contrarily, the 500 μM H2O2 concentration induced a stress state, characterized by a cell viability decrease from 1 day and a drastic cell growth arrest after 7 days leading to an uncomplete recovery after treatment. In conclusion, this study highlights the overall high capacity of cnidarian cells to cope with H2O2 and opens new perspective to investigate the molecular mechanisms involved in this peculiar resistance.
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Affiliation(s)
- Pauline Cotinat
- CNRS, INSERM, Institute for Research on Cancer and Aging, Nice, Université Côte d’Azur, Nice, France
- Institut Fédératif de Recherche – Ressources Marines (MARRES), Université Côte d’Azur, Nice, France
| | - Clara Fricano
- CNRS, INSERM, Institute for Research on Cancer and Aging, Nice, Université Côte d’Azur, Nice, France
- Institut Fédératif de Recherche – Ressources Marines (MARRES), Université Côte d’Azur, Nice, France
| | - Gaëlle Toullec
- CNRS, INSERM, Institute for Research on Cancer and Aging, Nice, Université Côte d’Azur, Nice, France
| | - Eric Röttinger
- CNRS, INSERM, Institute for Research on Cancer and Aging, Nice, Université Côte d’Azur, Nice, France
- Institut Fédératif de Recherche – Ressources Marines (MARRES), Université Côte d’Azur, Nice, France
| | - Stéphanie Barnay-Verdier
- CNRS, INSERM, Institute for Research on Cancer and Aging, Nice, Université Côte d’Azur, Nice, France
- Institut Fédératif de Recherche – Ressources Marines (MARRES), Université Côte d’Azur, Nice, France
- UFR 927, Sorbonne Université, Paris, France
| | - Paola Furla
- CNRS, INSERM, Institute for Research on Cancer and Aging, Nice, Université Côte d’Azur, Nice, France
- Institut Fédératif de Recherche – Ressources Marines (MARRES), Université Côte d’Azur, Nice, France
- *Correspondence: Paola Furla,
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41
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Dungan AM, Hartman LM, Blackall LL, van Oppen MJH. Exploring microbiome engineering as a strategy for improved thermal tolerance in Exaiptasia diaphana. J Appl Microbiol 2022; 132:2940-2956. [PMID: 35104027 PMCID: PMC9303619 DOI: 10.1111/jam.15465] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 12/08/2021] [Accepted: 01/24/2022] [Indexed: 11/28/2022]
Abstract
Aims Fourteen percent of all living coral, equivalent to more than all the coral on the Great Barrier Reef, has died in the past decade as a result of climate change‐driven bleaching. Inspired by the ‘oxidative stress theory of coral bleaching’, we investigated whether a bacterial consortium designed to scavenge free radicals could integrate into the host microbiome and improve thermal tolerance of the coral model, Exaiptasia diaphana. Methods and Results E. diaphana anemones were inoculated with a consortium of high free radical scavenging (FRS) bacteria, a consortium of congeneric low FRS bacteria, or sterile seawater as a control, then exposed to elevated temperature. Increases in the relative abundance of Labrenzia during the first 2 weeks following the last inoculation provided evidence for temporary inoculum integration into the E. diaphana microbiome. Initial uptake of other consortium members was inconsistent, and these bacteria did not persist either in E. diaphana’s microbiome over time. Given their non‐integration into the host microbiome, the ability of the FRS consortium to mitigate thermal stress could not be assessed. Importantly, there were no physiological impacts (negative or positive) of the bacterial inoculations on the holobiont. Conclusions The introduced bacteria were not maintained in the anemone microbiome over time, thus, their protective effect is unknown. Achieving long‐term integration of bacteria into cnidarian microbiomes remains a research priority. Significance and Impact of the Study Microbiome engineering strategies to mitigate coral bleaching may assist coral reefs in their persistence until climate change has been curbed. This study provides insights that will inform microbiome manipulation approaches in coral bleaching mitigation research.
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Affiliation(s)
- Ashley M Dungan
- School of BioSciences, The University of Melbourne, Melbourne, VIC, Australia
| | - Leon M Hartman
- School of BioSciences, The University of Melbourne, Melbourne, VIC, Australia.,Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Linda L Blackall
- School of BioSciences, The University of Melbourne, Melbourne, VIC, Australia
| | - Madeleine J H van Oppen
- School of BioSciences, The University of Melbourne, Melbourne, VIC, Australia.,Australian Institute of Marine Science, Townsville, Australia
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42
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Denny MW, Dowd WW. Physiological Consequences of Oceanic Environmental Variation: Life from a Pelagic Organism's Perspective. ANNUAL REVIEW OF MARINE SCIENCE 2022; 14:25-48. [PMID: 34314598 DOI: 10.1146/annurev-marine-040221-115454] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
To better understand life in the sea, marine scientists must first quantify how individual organisms experience their environment, and then describe how organismal performance depends on that experience. In this review, we first explore marine environmental variation from the perspective of pelagic organisms, the most abundant life forms in the ocean. Generation time, the ability to move relative to the surrounding water (even slowly), and the presence of environmental gradients at all spatial scales play dominant roles in determining the variation experienced by individuals, but this variation remains difficult to quantify. We then use this insight to critically examine current understanding of the environmental physiology of pelagic marine organisms. Physiologists have begun to grapple with the complexity presented by environmental variation, and promising frameworks exist for predicting and/or interpreting the consequences for physiological performance. However, new technology needs to be developed and much difficult empirical work remains, especially in quantifying response times to environmental variation and the interactions among multiple covarying factors. We call on the field of global-change biology to undertake these important challenges.
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Affiliation(s)
- Mark W Denny
- Hopkins Marine Station, Stanford University, Pacific Grove, California 93950, USA;
| | - W Wesley Dowd
- School of Biological Sciences, Washington State University, Pullman, Washington 99164, USA;
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43
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Leggat W, Heron SF, Fordyce A, Suggett DJ, Ainsworth TD. Experiment Degree Heating Week (eDHW) as a novel metric to reconcile and validate past and future global coral bleaching studies. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 301:113919. [PMID: 34731944 DOI: 10.1016/j.jenvman.2021.113919] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 09/27/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
Coral bleaching has increasingly impacted reefs worldwide over the past four decades. Despite almost 40 years of research into the mechanistic, physiological, ecological, biophysical and climatic drivers of coral bleaching, metrics to allow comparison between ecological observations and experimental simulations still do not exist. Here we describe a novel metric - experimental Degree Heating Week (eDHW) - with which to standardise the persistently variable thermal conditions employed across experimental studies of coral bleaching by modify the widely used Degree Heating Week (DHW) metric used in ecological studies to standardise cumulative heat loading.
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Affiliation(s)
- William Leggat
- School of Environmental and Life Sciences, University of Newcastle, Newcastle, Australia.
| | - Scott F Heron
- Physics and Marine Geophysical Laboratory, College of Science and Engineering, James Cook University, Townsville, Australia
| | - Alexander Fordyce
- School of Environmental and Life Sciences, University of Newcastle, Newcastle, Australia
| | - David J Suggett
- University of Technology Sydney, Climate Change Cluster, Faculty of Science, Sydney, Australia
| | - Tracy D Ainsworth
- Biological, Earth, and Environmental Sciences, University of New South Wales, Sydney, Australia
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44
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da Silva Fonseca J, de Barros Marangoni LF, Marques JA, Bianchini A. Elevated Temperature and Exposure to Copper Leads to Changes in the Antioxidant Defense System of the Reef-Building Coral Mussismilia harttii. Front Physiol 2021; 12:804678. [PMID: 35002777 PMCID: PMC8734030 DOI: 10.3389/fphys.2021.804678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/01/2021] [Indexed: 11/17/2022] Open
Abstract
The frequency and severity of coral bleaching events have increased in recent years. Global warming and contamination are primarily responsible for triggering these responses in corals. Thus, the objective of this study was to evaluate the isolated and combined effects of elevated temperature and exposure to copper (Cu) on responses of the antioxidant defense system of coral Mussismilia harttii. In a marine mesocosm, fragments of the coral were exposed to three temperatures (25.0, 26.6, and 27.3°C) and three concentrations of Cu (2.9, 5.4, and 8.6 μg/L) for up to 12 days. Levels of reduced glutathione (GSH) and the activity of enzymes, such as superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and glutamate cysteine ligase (GCL), were evaluated on the corals and symbionts. The short exposure to isolated and combined stressors caused a reduction in GSH levels and inhibition of the activity of antioxidant enzymes. After prolonged exposure, the combination of stressors continued to reduce GSH levels and SOD, CAT, and GCL activity in symbionts and GST activity in host corals. GCL activity was the parameter most affected by stressors, remaining inhibited after 12-days exposure. Interesting that long-term exposure to stressors stimulated antioxidant defense proteins in M. harttii, demonstrating a counteracting response that may beneficiate the oxidative state. These results, combined with other studies already published suggest that the antioxidant system should be further studied in order to understand the mechanisms of tolerance of South Atlantic reefs.
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Affiliation(s)
- Juliana da Silva Fonseca
- Programa de Pós-Graduação em Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, Brazil
| | - Laura Fernandes de Barros Marangoni
- Programa de Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande, Rio Grande, Brazil
- Instituto Coral Vivo, Santa Cruz Cabrália, Brazil
- Smithsonian Tropical Research Institute, Ciudad de Panamá, Panama
| | - Joseane Aparecida Marques
- Programa de Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande, Rio Grande, Brazil
- Instituto Coral Vivo, Santa Cruz Cabrália, Brazil
| | - Adalto Bianchini
- Instituto Coral Vivo, Santa Cruz Cabrália, Brazil
- Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, Brazil
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45
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MacDonald C, Pinheiro HT, Shepherd B, Phelps TAY, Rocha LA. Disturbance and distribution gradients influence resource availability and feeding behaviours in corallivore fishes following a warm-water anomaly. Sci Rep 2021; 11:23656. [PMID: 34880357 PMCID: PMC8654952 DOI: 10.1038/s41598-021-03061-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 11/24/2021] [Indexed: 11/09/2022] Open
Abstract
Understanding interactions between spatial gradients in disturbances, species distributions and species’ resilience mechanisms is critical to identifying processes that mediate environmental change. On coral reefs, a global expansion of coral bleaching is likely to drive spatiotemporal pulses in resource quality for obligate coral associates. Using technical diving and statistical modelling we evaluated how depth gradients in coral distribution, coral bleaching, and competitor density interact with the quality, preference and use of coral resources by corallivore fishes immediately following a warm-water anomaly. Bleaching responses varied among coral genera and depths but attenuated substantially between 3 and 47 m for key prey genera (Acropora and Pocillopora). While total coral cover declined with depth, the cover of pigmented corals increased slightly. The abundances of three focal obligate-corallivore butterflyfish species also decreased with depth and were not related to spatial patterns in coral bleaching. Overall, all species selectively foraged on pigmented corals. However, the most abundant species avoided feeding on bleached corals more successfully in deeper waters, where bleaching prevalence and conspecific densities were lower. These results suggest that, as coral bleaching increases, energy trade-offs related to distributions and resource acquisition will vary with depth for some coral-associated species.
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Affiliation(s)
- Chancey MacDonald
- Department of Ichthyology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA, 90118, USA.
| | - Hudson T Pinheiro
- Department of Ichthyology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA, 90118, USA.,Center of Marine Biology, University of São Paulo, Rod. Dr. Manoel Hipólito do Rego, km 131.5, São Sebastião, SP, 11612-109, Brazil
| | - Bart Shepherd
- Steinhart Aquarium, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA, 90118, USA
| | - Tyler A Y Phelps
- Department of Ichthyology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA, 90118, USA.,Department of Biology, San Francisco State University, 1600 Holloway Ave, San Francisco, CA, 94132, USA
| | - Luiz A Rocha
- Department of Ichthyology, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA, 90118, USA
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46
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Rädecker N, Pogoreutz C, Gegner HM, Cárdenas A, Perna G, Geißler L, Roth F, Bougoure J, Guagliardo P, Struck U, Wild C, Pernice M, Raina JB, Meibom A, Voolstra CR. Heat stress reduces the contribution of diazotrophs to coral holobiont nitrogen cycling. THE ISME JOURNAL 2021; 16:1110-1118. [PMID: 34857934 PMCID: PMC8941099 DOI: 10.1038/s41396-021-01158-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 12/22/2022]
Abstract
Efficient nutrient cycling in the coral-algal symbiosis requires constant but limited nitrogen availability. Coral-associated diazotrophs, i.e., prokaryotes capable of fixing dinitrogen, may thus support productivity in a stable coral-algal symbiosis but could contribute to its breakdown when overstimulated. However, the effects of environmental conditions on diazotroph communities and their interaction with other members of the coral holobiont remain poorly understood. Here we assessed the effects of heat stress on diazotroph diversity and their contribution to holobiont nutrient cycling in the reef-building coral Stylophora pistillata from the central Red Sea. In a stable symbiotic state, we found that nitrogen fixation by coral-associated diazotrophs constitutes a source of nitrogen to the algal symbionts. Heat stress caused an increase in nitrogen fixation concomitant with a change in diazotroph communities. Yet, this additional fixed nitrogen was not assimilated by the coral tissue or the algal symbionts. We conclude that although diazotrophs may support coral holobiont functioning under low nitrogen availability, altered nutrient cycling during heat stress abates the dependence of the coral host and its algal symbionts on diazotroph-derived nitrogen. Consequently, the role of nitrogen fixation in the coral holobiont is strongly dependent on its nutritional status and varies dynamically with environmental conditions.
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Affiliation(s)
- Nils Rädecker
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia. .,Department of Biology, University of Konstanz, Konstanz, Germany. .,Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Claudia Pogoreutz
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, Germany
| | - Hagen M Gegner
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Metabolomics Core Technology Platform, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
| | - Anny Cárdenas
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, Germany
| | - Gabriela Perna
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, Germany
| | - Laura Geißler
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Florian Roth
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Baltic Sea Centre, Stockholm University, Stockholm, Sweden.,Faculty of Biological and Environmental Sciences, Tvärminne Zoological Station, University of Helsinki, Helsinki, Finland
| | - Jeremy Bougoure
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Perth, WA, Australia
| | - Paul Guagliardo
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Perth, WA, Australia
| | - Ulrich Struck
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany.,Department of Earth Sciences, Freie Universität Berlin, Berlin, Germany
| | - Christian Wild
- Faculty of Biology and Chemistry, Marine Ecology Department, University of Bremen, Bremen, Germany
| | - Mathieu Pernice
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Jean-Baptiste Raina
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Anders Meibom
- Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Center for Advanced Surface Analysis, Institute of Earth Sciences, Université de Lausanne, Lausanne, Switzerland
| | - Christian R Voolstra
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, Germany
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47
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Pérez-Rosales G, Rouzé H, Torda G, Bongaerts P, Pichon M, Parravicini V, Hédouin L. Mesophotic coral communities escape thermal coral bleaching in French Polynesia. ROYAL SOCIETY OPEN SCIENCE 2021; 8:210139. [PMID: 34804562 PMCID: PMC8580450 DOI: 10.1098/rsos.210139] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 10/11/2021] [Indexed: 06/01/2023]
Abstract
Climate change and consequent coral bleaching are causing the disappearance of reef-building corals worldwide. While bleaching episodes significantly impact shallow waters, little is known about their impact on mesophotic coral communities. We studied the prevalence of coral bleaching two to three months after a heat stress event, along an extreme depth range from 6 to 90 m in French Polynesia. Bayesian modelling showed a decreasing probability of bleaching of all coral genera over depth, with little to no bleaching observed at lower mesophotic depths (greater than or equal to 60 m). We found that depth-generalist corals benefit more from increasing depth than depth-specialists (corals with a narrow depth range). Our data suggest that the reduced prevalence of bleaching with depth, especially from shallow to upper mesophotic depths (40 m), had a stronger relation with the light-irradiance attenuation than temperature. While acknowledging the geographical and temporal variability of the role of mesophotic reefs as spatial refuges during thermal stress, we ought to understand why coral bleaching reduces with depth. Future studies should consider repeated monitoring and detailed ecophysiological and environmental data. Our study demonstrated how increasing depth may offer a level of protection and that lower mesophotic communities could escape the impacts of a thermal bleaching event.
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Affiliation(s)
- Gonzalo Pérez-Rosales
- PSL Research University, EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013 Papetoai, 98729 Moorea, French Polynesia
- PSL Université Paris: EPHE-UPVD-CNRS, USR 3278 CRIOBE, Université de Perpignan, 52 Avenue Paul Alduy, 66860 Perpignan, France
| | - Héloïse Rouzé
- PSL Research University, EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013 Papetoai, 98729 Moorea, French Polynesia
- PSL Université Paris: EPHE-UPVD-CNRS, USR 3278 CRIOBE, Université de Perpignan, 52 Avenue Paul Alduy, 66860 Perpignan, France
| | - Gergely Torda
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
| | - Pim Bongaerts
- California Academy of Sciences, San Francisco, CA 94118, USA
| | - Michel Pichon
- Biodiversity Section, Queensland Museum, Townsville, QLD 4811, Australia
| | | | - Valeriano Parravicini
- PSL Université Paris: EPHE-UPVD-CNRS, USR 3278 CRIOBE, Université de Perpignan, 52 Avenue Paul Alduy, 66860 Perpignan, France
| | - Laetitia Hédouin
- PSL Research University, EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013 Papetoai, 98729 Moorea, French Polynesia
- PSL Université Paris: EPHE-UPVD-CNRS, USR 3278 CRIOBE, Université de Perpignan, 52 Avenue Paul Alduy, 66860 Perpignan, France
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48
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Ziegler M, Anton A, Klein SG, Rädecker N, Geraldi NR, Schmidt-Roach S, Saderne V, Mumby PJ, Cziesielski MJ, Martin C, Frölicher TL, Pandolfi JM, Suggett DJ, Aranda M, Duarte CM, Voolstra CR. Integrating environmental variability to broaden the research on coral responses to future ocean conditions. GLOBAL CHANGE BIOLOGY 2021; 27:5532-5546. [PMID: 34391212 DOI: 10.1111/gcb.15840] [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: 03/24/2021] [Revised: 06/19/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Our understanding of the response of reef-building corals to changes in their physical environment is largely based on laboratory experiments, analysis of long-term field data, and model projections. Experimental data provide unique insights into how organisms respond to variation of environmental drivers. However, an assessment of how well experimental conditions cover the breadth of environmental conditions and variability where corals live successfully is missing. Here, we compiled and analyzed a globally distributed dataset of in-situ seasonal and diurnal variability of key environmental drivers (temperature, pCO2 , and O2 ) critical for the growth and livelihood of reef-building corals. Using a meta-analysis approach, we compared the variability of environmental conditions assayed in coral experimental studies to current and projected conditions in their natural habitats. We found that annual temperature profiles projected for the end of the 21st century were characterized by distributional shifts in temperatures with warmer winters and longer warm periods in the summer, not just peak temperatures. Furthermore, short-term hourly fluctuations of temperature and pCO2 may regularly expose corals to conditions beyond the projected average increases for the end of the 21st century. Coral reef sites varied in the degree of coupling between temperature, pCO2 , and dissolved O2 , which warrants site-specific, differentiated experimental approaches depending on the local hydrography and influence of biological processes on the carbonate system and O2 availability. Our analysis highlights that a large portion of the natural environmental variability at short and long timescales is underexplored in experimental designs, which may provide a path to extend our understanding on the response of corals to global climate change.
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Affiliation(s)
- Maren Ziegler
- Department of Animal Ecology & Systematics, Justus Liebig University Giessen, Giessen, Germany
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Andrea Anton
- Red Sea Research Center (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
- Global Change Research Group, IMEDEA (CSIC-UIB), Mediterranean Institute for Advanced Studies, Esporles (Illes Balears), Spain
| | - Shannon G Klein
- Red Sea Research Center (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Nils Rädecker
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
- Department of Biology, University of Konstanz, Konstanz, Germany
- Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Nathan R Geraldi
- Red Sea Research Center (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Sebastian Schmidt-Roach
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Vincent Saderne
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Peter J Mumby
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia
| | - Maha J Cziesielski
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Cecilia Martin
- Red Sea Research Center (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Thomas L Frölicher
- Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - John M Pandolfi
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Qld, Australia
| | - David J Suggett
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Sydney, NSW, Australia
| | - Manuel Aranda
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Carlos M Duarte
- Red Sea Research Center (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Christian R Voolstra
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
- Department of Biology, University of Konstanz, Konstanz, Germany
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49
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Maire J, Blackall LL, van Oppen MJH. Intracellular Bacterial Symbionts in Corals: Challenges and Future Directions. Microorganisms 2021; 9:2209. [PMID: 34835335 PMCID: PMC8619543 DOI: 10.3390/microorganisms9112209] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/21/2021] [Accepted: 10/21/2021] [Indexed: 02/07/2023] Open
Abstract
Corals are the main primary producers of coral reefs and build the three-dimensional reef structure that provides habitat to more than 25% of all marine eukaryotes. They harbor a complex consortium of microorganisms, including bacteria, archaea, fungi, viruses, and protists, which they rely on for their survival. The symbiosis between corals and bacteria is poorly studied, and their symbiotic relationships with intracellular bacteria are only just beginning to be acknowledged. In this review, we emphasize the importance of characterizing intracellular bacteria associated with corals and explore how successful approaches used to study such microorganisms in other systems could be adapted for research on corals. We propose a framework for the description, identification, and functional characterization of coral-associated intracellular bacterial symbionts. Finally, we highlight the possible value of intracellular bacteria in microbiome manipulation and mitigating coral bleaching.
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Affiliation(s)
- Justin Maire
- School of Biosciences, The University of Melbourne, Melbourne, VIC 3010, Australia; (L.L.B.); (M.J.H.v.O.)
| | - Linda L. Blackall
- School of Biosciences, The University of Melbourne, Melbourne, VIC 3010, Australia; (L.L.B.); (M.J.H.v.O.)
| | - Madeleine J. H. van Oppen
- School of Biosciences, The University of Melbourne, Melbourne, VIC 3010, Australia; (L.L.B.); (M.J.H.v.O.)
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
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50
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Abstract
Recent human activity has profoundly transformed Earth biomes on a scale and at rates that are unprecedented. Given the central role of symbioses in ecosystem processes, functions, and services throughout the Earth biosphere, the impacts of human-driven change on symbioses are critical to understand. Symbioses are not merely collections of organisms, but co-evolved partners that arise from the synergistic combination and action of different genetic programs. They function with varying degrees of permanence and selection as emergent units with substantial potential for combinatorial and evolutionary innovation in both structure and function. Following an articulation of operational definitions of symbiosis and related concepts and characteristics of the Anthropocene, we outline a basic typology of anthropogenic change (AC) and a conceptual framework for how AC might mechanistically impact symbioses with select case examples to highlight our perspective. We discuss surprising connections between symbiosis and the Anthropocene, suggesting ways in which new symbioses could arise due to AC, how symbioses could be agents of ecosystem change, and how symbioses, broadly defined, of humans and “farmed” organisms may have launched the Anthropocene. We conclude with reflections on the robustness of symbioses to AC and our perspective on the importance of symbioses as ecosystem keystones and the need to tackle anthropogenic challenges as wise and humble stewards embedded within the system.
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Affiliation(s)
- Erik F Y Hom
- Department of Biology and Center for Biodiversity and Conservation Research, University of Mississippi, University, MS 38677 USA
| | - Alexandra S Penn
- Department of Sociology and Centre for Evaluation of Complexity Across the Nexus, University of Surrey, Guildford, Surrey, GU2 7XH UK
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