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Li J, Li W, Huang Y, Bu H, Zhang K, Lin S. Phosphorus limitation intensifies heat-stress effects on the potential mutualistic capacity in the coral-derived Symbiodinium. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:173912. [PMID: 38871329 DOI: 10.1016/j.scitotenv.2024.173912] [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: 12/20/2023] [Revised: 05/08/2024] [Accepted: 06/08/2024] [Indexed: 06/15/2024]
Abstract
Coral reef ecosystems have been severely ravaged by global warming and eutrophication. Eutrophication often originates from nitrogen (N) overloading that creates stoichiometric phosphorus (P) limitation, which can be aggravated by sea surface temperature rises that enhances stratification. However, how P-limitation interacts with thermal stress to impact coral-Symbiodiniaceae mutualism is poorly understood and underexplored. Here, we investigated the effect of P-limitation (P-depleted vs. P-replete) superimposed on heat stress (31 °C vs. 25 °C) on a Symbiodinium strain newly isolated from the coral host by a 14-day incubation experiment. The heat and P-limitation co-stress induced an increase in alkaline phosphatase activity and reppressed cell division, photosynthetic efficiency, and expression of N uptake and assimilation genes. Moreover, P limitation intensified downregulation of carbon fixation (light and dark reaction) and metabolism (glycolysis) pathways in heat stressed Symbiodinium. Notably, co-stress elicited a marked transcriptional downregulation of genes encoding photosynthates transporters and microbe-associated molecular patterns, potentially undermining the mutualism potential. This work sheds light on the interactive effects of P-limitation and heat stress on coral symbionts, indicating that nutrient imbalance in the coral reef ecosystem can intensify heat-stress effects on the mutualistic capacity of Symbiodiniaceae.
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Affiliation(s)
- Jiashun Li
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Wenzhe Li
- State Key Laboratory of Marine Resource Utilization in the South China Sea and School of Marine Biology and Fisheries, Hainan University, Haikou, China
| | - Yulin Huang
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Hailu Bu
- State Key Laboratory of Marine Resource Utilization in the South China Sea and School of Marine Biology and Fisheries, Hainan University, Haikou, China
| | - Kaidian Zhang
- State Key Laboratory of Marine Resource Utilization in the South China Sea and School of Marine Biology and Fisheries, Hainan University, Haikou, China.
| | - Senjie Lin
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA.
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2
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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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3
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Varasteh T, Lima MS, Silva TA, da Cruz MLR, Ahmadi RA, Atella GC, Attias M, Swings J, de Souza W, Thompson FL, Thompson CC. The dispersant Corexit 9500 and (dispersed) oil are lethal to coral endosymbionts. MARINE POLLUTION BULLETIN 2024; 203:116491. [PMID: 38754321 DOI: 10.1016/j.marpolbul.2024.116491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 04/30/2024] [Accepted: 05/09/2024] [Indexed: 05/18/2024]
Abstract
Endosymbionts (Symbiodiniaceae) play a vital role in the health of corals. Seawater pollution can harm these endosymbionts and dispersants used during oil spill cleanup can be extremely toxic to these organisms. Here, we examined the impact of oil and a specific dispersant, Corexit-9500, on two representative endosymbionts - Symbiodinium and Cladocopium - from the Southwestern endemic coral Mussismilia braziliensis. The survival and photosynthetic potential of the endosymbionts decreased dramatically after exposure to the dispersant and oil by ~25 % after 2 h and ~50 % after 7 days. Low concentrations of dispersant (0.005 ml/l) and dispersed oil (Polycyclic Aromatic Hydrocarbons, 1132 μg/l; Total Petroleum Hydrocarbons, 595 μg/l) proved highly toxic to both Symbiodinium and Cladocopium. These levels triggered a reduction in growth rate, cell size, and cell wall thickness. After a few hours of exposure, cellular organelles were damaged or destroyed. These acute toxic effects underline the fragile nature of coral endosymbionts.
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Affiliation(s)
- Tooba Varasteh
- Laboratory of Microbiology, Biology Institute, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Michele S Lima
- Laboratory of Microbiology, Biology Institute, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Tatiana A Silva
- Laboratory of Celullar Ultrastructure Hertha Meyer, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Maria Luíza R da Cruz
- Laboratory of Microbiology, Biology Institute, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Reza Amir Ahmadi
- Laboratory of Microbiology, Biology Institute, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Georgia C Atella
- Laboratory of Lipids Biochemistry and Lipoprotein, Biochemistry Institute Leopoldo de Meis, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Marcia Attias
- Laboratory of Celullar Ultrastructure Hertha Meyer, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Jean Swings
- Laboratory of Microbiology, Biology Institute, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Wanderley de Souza
- Laboratory of Celullar Ultrastructure Hertha Meyer, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Fabiano L Thompson
- Laboratory of Microbiology, Biology Institute, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
| | - Cristiane C Thompson
- Laboratory of Microbiology, Biology Institute, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
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4
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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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5
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Kemp DW, Hoadley KD, Lewis AM, Wham DC, Smith RT, Warner ME, LaJeunesse TC. Thermotolerant coral-algal mutualisms maintain high rates of nutrient transfer while exposed to heat stress. Proc Biol Sci 2023; 290:20231403. [PMID: 37727091 PMCID: PMC10509592 DOI: 10.1098/rspb.2023.1403] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 08/15/2023] [Indexed: 09/21/2023] Open
Abstract
Symbiotic mutualisms are essential to ecosystems and numerous species across the tree of life. For reef-building corals, the benefits of their association with endosymbiotic dinoflagellates differ within and across taxa, and nutrient exchange between these partners is influenced by environmental conditions. Furthermore, it is widely assumed that corals associated with symbionts in the genus Durusdinium tolerate high thermal stress at the expense of lower nutrient exchange to support coral growth. We traced both inorganic carbon (H13CO3-) and nitrate (15NO3-) uptake by divergent symbiont species and quantified nutrient transfer to the host coral under normal temperatures as well as in colonies exposed to high thermal stress. Colonies representative of diverse coral taxa associated with Durusdinium trenchii or Cladocopium spp. exhibited similar nutrient exchange under ambient conditions. By contrast, heat-exposed colonies with D. trenchii experienced less physiological stress than conspecifics with Cladocopium spp. while high carbon assimilation and nutrient transfer to the host was maintained. This discovery differs from the prevailing notion that these mutualisms inevitably suffer trade-offs in physiological performance. These findings emphasize that many host-symbiont combinations adapted to high-temperature equatorial environments are high-functioning mutualisms; and why their increased prevalence is likely to be important to the future productivity and stability of coral reef ecosystems.
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Affiliation(s)
- Dustin W. Kemp
- Department of Biology, University of Alabama at Birmingham, AL, USA
| | | | - Allison M. Lewis
- Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Drew C. Wham
- Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Robin T. Smith
- Center for Marine and Environmental Studies, University of the Virgin Islands, St. Thomas, VI, USA
| | - Mark E. Warner
- School of Marine Science and Policy, University of Delaware, Lewes, DE, USA
| | - Todd C. LaJeunesse
- Department of Biology, Pennsylvania State University, University Park, PA, USA
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Sun AZ, Chen JH, Jin XQ, Li H, Guo FQ. Supplementing the Nuclear-Encoded PSII Subunit D1 Induces Dramatic Metabolic Reprogramming in Flag Leaves during Grain Filling in Rice. PLANTS (BASEL, SWITZERLAND) 2023; 12:3009. [PMID: 37631220 PMCID: PMC10458752 DOI: 10.3390/plants12163009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/11/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023]
Abstract
Our previous study has demonstrated that the nuclear-origin supplementation of the PSII core subunit D1 protein stimulates growth and increases grain yields in transgenic rice plants by enhancing photosynthetic efficiency. In this study, the underlying mechanisms have been explored regarding how the enhanced photosynthetic capacity affects metabolic activities in the transgenic plants of rice harboring the integrated transgene RbcSPTP-OspsbA cDNA, cloned from rice, under control of the AtHsfA2 promoter and N-terminal fused with the plastid-transit peptide sequence (PTP) cloned from the AtRbcS. Here, a comparative metabolomic analysis was performed using LC-MS in flag leaves of the transgenic rice plants during the grain-filling stage. Critically, the dramatic reduction in the quantities of nucleotides and certain free amino acids was detected, suggesting that the increased photosynthetic assimilation and grain yield in the transgenic plants correlates with the reduced contents of free nucleotides and the amino acids such as glutamine and glutamic acid, which are cellular nitrogen sources. These results suggest that enhanced photosynthesis needs consuming more free nucleotides and nitrogen sources to support the increase in biomass and yields, as exhibited in transgenic rice plants. Unexpectedly, dramatic changes were measured in the contents of flavonoids in the flag leaves, suggesting that a tight and coordinated relationship exists between increasing photosynthetic assimilation and flavonoid biosynthesis. Consistent with the enhanced photosynthetic efficiency, the substantial increase was measured in the content of starch, which is the primary product of the Calvin-Benson cycle, in the transgenic rice plants under field growth conditions.
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Affiliation(s)
- Ai-Zhen Sun
- The National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (A.-Z.S.); (J.-H.C.); (X.-Q.J.); (H.L.)
| | - Juan-Hua Chen
- The National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (A.-Z.S.); (J.-H.C.); (X.-Q.J.); (H.L.)
| | - Xue-Qi Jin
- The National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (A.-Z.S.); (J.-H.C.); (X.-Q.J.); (H.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Han Li
- The National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (A.-Z.S.); (J.-H.C.); (X.-Q.J.); (H.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fang-Qing Guo
- The National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (A.-Z.S.); (J.-H.C.); (X.-Q.J.); (H.L.)
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7
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Amario M, Villela LB, Jardim-Messeder D, Silva-Lima AW, Rosado PM, de Moura RL, Sachetto-Martins G, Chaloub RM, Salomon PS. Physiological response of Symbiodiniaceae to thermal stress: Reactive oxygen species, photosynthesis, and relative cell size. PLoS One 2023; 18:e0284717. [PMID: 37535627 PMCID: PMC10399794 DOI: 10.1371/journal.pone.0284717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Accepted: 04/06/2023] [Indexed: 08/05/2023] Open
Abstract
This study investigates the physiological response to heat stress of three genetically different Symbiodiniaceae strains isolated from the scleractinian coral Mussismilia braziliensis, endemic of the Abrolhos Bank, Brazil. Cultures of two Symbiodinium sp. and one Cladocopium sp. were exposed to a stepwise increase in temperature (2°C every second day) ranging from 26°C (modal temperature in Abrolhos) to 32°C (just above the maximum temperature registered in Abrolhos during the third global bleaching event-TGBE). After the cultures reached their final testing temperature, reactive oxygen species (ROS) production, single cell attributes (relative cell size and chlorophyll fluorescence), and photosynthetic efficiency (effective (Y(II)) and maximum (Fv/Fm) quantum yields) were measured within 4 h and 72 h. Non-photochemical coefficient (NPQ) was estimated based on fluorescence values. Population average ROS production was variable across strains and exposure times, reaching up a 2-fold increase at 32°C in one of the Symbiodinium sp. strains. A marked intrapopulation difference was observed in ROS production, with 5 to 25% of the cells producing up to 10 times more than the population average, highlighting the importance of single cell approaches to assess population physiology. Average cell size increases at higher temperatures, likely resulting from cell cycle arrest, whereas chlorophyll fluorescence decreased, especially in 4 h, indicating a photoacclimation response. The conditions tested do not seem to have elicited loss of photosynthetic efficiency nor the activation of non-photochemical mechanisms in the cells. Our results unveiled a generalized thermotolerance in three Symbiodiniaceae strains originated from Abrolhos' corals. Inter and intra-specific variability could be detected, likely reflecting the genetic differences among the strains.
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Affiliation(s)
- Michelle Amario
- Laboratório de Fitoplâncton Marinho, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Programa de Pós-Graduação em Genética, Rio de Janeiro, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lívia Bonetti Villela
- Laboratório de Fitoplâncton Marinho, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Programa de Pós-Graduação em Genética, Rio de Janeiro, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Douglas Jardim-Messeder
- Laboratório de Genômica Funcional e Transdução de Sinal, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Instituto de Biologia, Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Biologia Molecular de Plantas, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Arthur Weiss Silva-Lima
- Laboratório de Fitoplâncton Marinho, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Rodrigo Leão de Moura
- Laboratório de Monitoramento da Biodiversidade, Instituto de Biologia SAGE-COPPE, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gilberto Sachetto-Martins
- Laboratório de Genômica Funcional e Transdução de Sinal, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Instituto de Biologia, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ricardo Moreira Chaloub
- Laboratório de Estudos Aplicados em Fotossíntese, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo Sergio Salomon
- Laboratório de Fitoplâncton Marinho, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
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Hazraty-Kari S, Morita M, Tavakoli-Kolour P, Nakamura T, Harii S. Reactions of juvenile coral to three years of consecutive thermal stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 863:161227. [PMID: 36586691 DOI: 10.1016/j.scitotenv.2022.161227] [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: 10/24/2022] [Revised: 12/06/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023]
Abstract
As global temperatures continue to rise, corals are being exposed to increasing heat stress throughout their early life stages; however, the impact of this phenomenon is poorly understood. We exposed the reef-building coral Acropora tenuis juveniles to ∼26-28 °C (control) and ∼ 31 °C (heat stress) for one week per year over three consecutive years. In the first year of heat stress, >96 % of juveniles survived despite symbiotic algal densities in juvenile corals declining. In comparison, survival rates in the third year of heat stress declined to 50 %. Survival rates under natural conditions after stress also gradually decreased in the stressed groups. The rate in the reduction of survivorship was prominent in the consecutive thermally stressed groups (juveniles stressed twice in two years). Symbiotic algal density and photosynthetic activity (Fv/Fm) also declined in stressed juvenile groups. However, heat stress did not significantly affect the growth of juveniles. In the third year of heat stress, temperature negatively affected the physiology of juveniles in terms of survivorship, brightness (an indicator of bleaching), symbiotic algal density, and photosynthetic efficiency. Stress across consecutive years appeared to cause the survivorship of juvenile corals to decline, with three years of stress contributing to the severe decline of a reef. In conclusion, A. tenuis juveniles are not able to acclimatize to heat stress, with successive heat waves of <7 days in the summer potentially negatively affecting resilience.
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Affiliation(s)
- Sanaz Hazraty-Kari
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan.
| | - Masaya Morita
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | | | - Takashi Nakamura
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan; Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | - Saki Harii
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan.
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9
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Solar radiation, temperature and the reproductive biology of the coral Lobactis scutaria in a changing climate. Sci Rep 2023; 13:246. [PMID: 36604569 PMCID: PMC9816315 DOI: 10.1038/s41598-022-27207-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 12/28/2022] [Indexed: 01/07/2023] Open
Abstract
Coral reefs worldwide are at risk due to climate change. Coral bleaching is becoming increasingly common and corals that survive bleaching events can suffer from temporary reproductive failure for several years. While water temperature is a key driver in causing coral bleaching, other environmental factors are involved, such as solar radiation. We investigated the individual and combined effects of temperature, photosynthetically active radiation (PAR), and ultraviolet radiation (UVR) on the spawning patterns and reproductive physiology of the Hawaiian mushroom coral Lobactis scutaria, using long-term experiments in aquaria. We examined effects on spawning timing, fertilisation success, and gamete physiology. Both warmer temperatures and filtering UVR altered the timing of spawning. Warmer temperatures caused a drop in fertilisation success. Warmer temperatures and higher PAR both negatively affected sperm and egg physiology. These results are concerning for the mushroom coral L. scutaria and similar reproductive data are urgently needed to predict future reproductive trends in other species. Nonetheless, thermal stress from global climate change will need to be adequately addressed to ensure the survival of reef-building corals in their natural environment throughout the next century and beyond. Until then, reproduction is likely to be increasingly impaired in a growing number of coral species.
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10
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Krämer WE, Iglesias-Prieto R, Enríquez S. Evaluation of the current understanding of the impact of climate change on coral physiology after three decades of experimental research. Commun Biol 2022; 5:1418. [PMID: 36572721 PMCID: PMC9792581 DOI: 10.1038/s42003-022-04353-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 12/08/2022] [Indexed: 12/27/2022] Open
Abstract
After three decades of coral research on the impacts of climate change, there is a wide consensus on the adverse effects of heat-stress, but the impacts of ocean acidification (OA) are not well established. Using a review of published studies and an experimental analysis, we confirm the large species-specific component of the OA response, which predicts moderate impacts on coral physiology and pigmentation by 2100 (scenario-B1 or SSP2-4.5), in contrast with the severe disturbances induced by only +2 °C of thermal anomaly. Accordingly, global warming represents a greater threat for coral calcification than OA. The incomplete understanding of the moderate OA response relies on insufficient attention to key regulatory processes of these symbioses, particularly the metabolic dependence of coral calcification on algal photosynthesis and host respiration. Our capacity to predict the future of coral reefs depends on a correct identification of the main targets and/or processes impacted by climate change stressors.
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Affiliation(s)
- Wiebke E. Krämer
- grid.9486.30000 0001 2159 0001Laboratory of Photobiology, Unidad Académica de Sistemas Arrecifales (Puerto Morelos), Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Quintana Roo Cancún, Mexico
| | - Roberto Iglesias-Prieto
- grid.9486.30000 0001 2159 0001Laboratory of Photobiology, Unidad Académica de Sistemas Arrecifales (Puerto Morelos), Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Quintana Roo Cancún, Mexico ,grid.29857.310000 0001 2097 4281Present Address: Department of Biology, The Pennsylvania State University, University Park, PA 16802 USA
| | - Susana Enríquez
- grid.9486.30000 0001 2159 0001Laboratory of Photobiology, Unidad Académica de Sistemas Arrecifales (Puerto Morelos), Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Quintana Roo Cancún, Mexico
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11
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Al-Hammady MA, Silva TF, Hussein HN, Saxena G, Modolo LV, Belasy MB, Westphal H, Farag MA. How do algae endosymbionts mediate for their coral host fitness under heat stress? A comprehensive mechanistic overview. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Nitschke MR, Rosset SL, Oakley CA, Gardner SG, Camp EF, Suggett DJ, Davy SK. The diversity and ecology of Symbiodiniaceae: A traits-based review. ADVANCES IN MARINE BIOLOGY 2022; 92:55-127. [PMID: 36208879 DOI: 10.1016/bs.amb.2022.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Among the most successful microeukaryotes to form mutualisms with animals are dinoflagellates in the family Symbiodiniaceae. These photosynthetic symbioses drive significant primary production and are responsible for the formation of coral reef ecosystems but are particularly sensitive when environmental conditions become extreme. Annual episodes of widespread coral bleaching (disassociation of the mutualistic partnership) and mortality are forecasted from the year 2060 under current trends of ocean warming. However, host cnidarians and dinoflagellate symbionts display exceptional genetic and functional diversity, and meaningful predictions of the future that embrace this biological complexity are difficult to make. A recent move to trait-based biology (and an understanding of how traits are shaped by the environment) has been adopted to move past this problem. The aim of this review is to: (1) provide an overview of the major cnidarian lineages that are symbiotic with Symbiodiniaceae; (2) summarise the symbiodiniacean genera associated with cnidarians with reference to recent changes in taxonomy and systematics; (3) examine the knowledge gaps in Symbiodiniaceae life history from a trait-based perspective; (4) review Symbiodiniaceae trait variation along three abiotic gradients (light, nutrients, and temperature); and (5) provide recommendations for future research of Symbiodiniaceae traits. We anticipate that a detailed understanding of traits will further reveal basic knowledge of the evolution and functional diversity of these mutualisms, as well as enhance future efforts to model stability and change in ecosystems dependent on cnidarian-dinoflagellate organisms.
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Affiliation(s)
- Matthew R Nitschke
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand; Climate Change Cluster, University of Technology Sydney, Broadway, NSW, Australia.
| | - Sabrina L Rosset
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Clinton A Oakley
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Stephanie G Gardner
- Center for Marine Science and Innovation, University of New South Wales Sydney, Kensington, NSW, Australia
| | - Emma F Camp
- Climate Change Cluster, University of Technology Sydney, Broadway, NSW, Australia
| | - David J Suggett
- Climate Change Cluster, University of Technology Sydney, Broadway, NSW, Australia
| | - Simon K Davy
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
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13
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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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14
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The role of the endolithic alga Ostreobium spp. during coral bleaching recovery. Sci Rep 2022; 12:2977. [PMID: 35194106 PMCID: PMC8863988 DOI: 10.1038/s41598-022-07017-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 01/25/2022] [Indexed: 02/06/2023] Open
Abstract
In this study, we explore how the Caribbean coral Orbicella faveolata recovers after bleaching, using fragments from 13 coral colonies exposed to heat stress (32 °C) for ten days. Biological parameters and coral optical properties were monitored during and after the stress. Increases in both, the excitation pressure over photosystem II (Qm) and pigment specific absorption (a*Chla) were observed in the stressed corals, associated with reductions in light absorption at the chlorophyll a red peak (De675) and symbiont population density. All coral fragments exposed to heat stress bleached but a fraction of the stressed corals recovered after removing the stress, as indicated by the reductions in Qm and increases in De675 and the symbiont population observed. This subsample of the experimentally bleached corals also showed blooms of the endolithic algae Ostreobium spp. underneath the tissue. Using a numerical model, we quantified the amount of incident light reflected by the coral, and absorbed by the different pigmented components: symbionts, host-tissue and Ostreobium spp. Our study supports the key contribution of Ostreobium spp. blooms near the skeletal surface, to coral recovery after bleaching by reducing skeleton reflectance. Endolithic blooms can thus significantly alleviate the high light stress that affects the remaining symbionts during the stress or when the coral has achieved the bleached phenotype.
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15
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Suescún-Bolívar LP, Thomé PE. The specific inhibition of glycerol synthesis and the phosphorylation of a putative MAPK give insight into the mechanism of osmotic sensing in a dinoflagellate symbiont. J Eukaryot Microbiol 2021; 69:e12883. [PMID: 34936156 DOI: 10.1111/jeu.12883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 12/03/2021] [Accepted: 12/14/2021] [Indexed: 11/30/2022]
Abstract
Signaling pathways are fundamental for the establishment and maintenance of diverse symbioses. The symbiosis of cnidarians and dinoflagellate algae is the foundation for the ecological success of coral reefs, involving the transfer of photosynthetic products from symbiont to host. However, signal transduction pathways for this symbiosis remain uncharacterized. Cultured and natural cnidarian symbionts can produce glycerol, one of the main translocated photosynthates. Here, we investigate whether a signal transduction pathway may be involved in inducing glycerol synthesis in cultured symbionts under an osmotic stress model. We evaluated the effect of specific inhibitors of the main transduction pathways, p38, JNK, and ERK 1/2 in Brevolium minutum, the symbiont of the Aiptasia model system. We found that glycerol production and the specific activity of the enzyme Gpdh were selectively inhibited by a p38 MAPK inhibitor. Additionally, the phosphorylation of a putative p38-like protein was rapidly detected. Finally, we studied the presence of each of the components of the p38 MAPK pathway in silico, in genomes and transcriptomes reported up to date for different symbiont types. We propose a model for the arrangement of this pathway in the family of dinoflagellate symbionts known as Symbiodiniaceae.
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Affiliation(s)
- L P Suescún-Bolívar
- Universidad Nacional Autónoma de México Instituto de Ciencias del Mar y Limnología Unidad Académica de Sistemas Arrecifales Puerto Morelos, Puerto Morelos, Mexico
| | - P E Thomé
- Universidad Nacional Autónoma de México Instituto de Ciencias del Mar y Limnología Unidad Académica de Sistemas Arrecifales Puerto Morelos, Puerto Morelos, Mexico
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16
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Ferreira V, Pavlaki MD, Martins R, Monteiro MS, Maia F, Tedim J, Soares AMVM, Calado R, Loureiro S. Effects of nanostructure antifouling biocides towards a coral species in the context of global changes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 799:149324. [PMID: 34371395 DOI: 10.1016/j.scitotenv.2021.149324] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 06/24/2021] [Accepted: 07/24/2021] [Indexed: 06/13/2023]
Abstract
Biofouling prevention is one of the biggest challenges faced by the maritime industry, but antifouling agents commonly impact marine ecosystems. Advances in antifouling technology include the use of nanomaterials. Herein we test an antifouling nano-additive based on the encapsulation of the biocide 4,5-dichloro-2-octyl-4-isothiazolin-3-one (DCOIT) in engineered silica nanocontainers (SiNC). The work aims to assess the biochemical and physiological effects on the symbiotic coral Sarcophyton cf. glaucum caused by (1) thermal stress and (2) DCOIT exposure (free or nanoencapsulated forms), in a climate change scenario. Accordingly, the following hypotheses were addressed: (H1) ocean warming can cause toxicity on S. cf. glaucum; (H2) the nanoencapsulation process decreases DCOIT toxicity towards this species; (H3) the biocide toxicity, free or encapsulated forms, can be affected by ocean warming. Coral fragments were exposed for seven days to DCOIT in both free and encapsulated forms, SiNC and negative controls, under two water temperature regimes (26 °C and 30.5 °C). Coral polyp behavior and photosynthetic efficiency were determined in the holobiont, while biochemical markers were assessed individually in the endosymbiont and coral host. Results showed transient coral polyp retraction and diminished photosynthetic efficiency in the presence of heat stress or free DCOIT, with effects being magnified in the presence of both stressors. The activity of catalase and glutathione-S-transferase were modulated by temperature in each partner of the symbiosis. The shifts in enzymatic activity were more pronounced in the presence of free DCOIT, but to a lower extent for encapsulated DCOIT. Increased levels of oxidative damage were detected under heat conditions. The findings highlight the physiological constrains elicited by the increase of seawater temperature to symbiotic corals and demonstrate that DCOIT toxicity can be minimized through encapsulation in SiNC. The presence of both stressors magnifies toxicity and confirm that ocean warming enhances the vulnerability of tropical photosynthetic corals to local stressors.
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Affiliation(s)
- Violeta Ferreira
- ApplEE Research Group, Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Maria D Pavlaki
- ApplEE Research Group, Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Roberto Martins
- ApplEE Research Group, Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Marta S Monteiro
- ApplEE Research Group, Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Frederico Maia
- Smallmatek - Small Materials and Technologies, Lda., Rua Canhas, 3810-075 Aveiro, Portugal
| | - João Tedim
- CICECO - Aveiro Institute of Materials & Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Amadeu M V M Soares
- ApplEE Research Group, Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Ricardo Calado
- ECOMARE, Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Susana Loureiro
- ApplEE Research Group, Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal
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17
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Thummasan M, Casareto BE, Ramphul C, Suzuki T, Toyoda K, Suzuki Y. Physiological responses (Hsps 60 and 32, caspase 3, H 2O 2 scavenging, and photosynthetic activity) of the coral Pocillopora damicornis under thermal and high nitrate stresses. MARINE POLLUTION BULLETIN 2021; 171:112737. [PMID: 34298325 DOI: 10.1016/j.marpolbul.2021.112737] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 06/22/2021] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
This study explored the physiological responses of the coral Pocillopora damicornis to high nitrate concentrations and thermal stresses. The expression of heat shock proteins Hsp60 and Hsp32, Symbiodiniaceae density, Chl a concentration, Fv/Fm, H2O2 scavenging, and caspase 3 activity varied during 60 h incubations at 28 °C or 32 °C, ambient or high nitrate (~10 μM) concentrations, and their combinations. In combined stresses, corals showed a rapid and high oxidation level negatively affecting the Symbiodiniaceae density and Chl a concentration at 12 h, followed by caspase 3 and Hsps upregulations that induced apoptosis, bleaching and tissue detachment. Corals under thermal stress showed the highest oxidation and upregulation of Hsps and caspase 3 resulting in coral discoloration. High nitrate treatment alone did not seriously affect the coral function. Results showed that combined stress treatment severely affected coral physiology and, judging from the condition of detached tissues, these corals might have lower chances to recover.
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Affiliation(s)
- Montaphat Thummasan
- Environmental and Energy System, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Beatriz Estela Casareto
- Environmental and Energy System, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
| | - Chitra Ramphul
- Environmental and Energy System, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Toshiyuki Suzuki
- Environmental and Energy System, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
| | - Keita Toyoda
- Environmental and Energy System, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
| | - Yoshimi Suzuki
- Environmental and Energy System, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
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18
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Avila-Magaña V, Kamel B, DeSalvo M, Gómez-Campo K, Enríquez S, Kitano H, Rohlfs RV, Iglesias-Prieto R, Medina M. Elucidating gene expression adaptation of phylogenetically divergent coral holobionts under heat stress. Nat Commun 2021; 12:5731. [PMID: 34593802 PMCID: PMC8484447 DOI: 10.1038/s41467-021-25950-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 09/01/2021] [Indexed: 02/08/2023] Open
Abstract
As coral reefs struggle to survive under climate change, it is crucial to know whether they have the capacity to withstand changing conditions, particularly increasing seawater temperatures. Thermal tolerance requires the integrative response of the different components of the coral holobiont (coral host, algal photosymbiont, and associated microbiome). Here, using a controlled thermal stress experiment across three divergent Caribbean coral species, we attempt to dissect holobiont member metatranscriptome responses from coral taxa with different sensitivities to heat stress and use phylogenetic ANOVA to study the evolution of gene expression adaptation. We show that coral response to heat stress is a complex trait derived from multiple interactions among holobiont members. We identify host and photosymbiont genes that exhibit lineage-specific expression level adaptation and uncover potential roles for bacterial associates in supplementing the metabolic needs of the coral-photosymbiont duo during heat stress. Our results stress the importance of integrative and comparative approaches across a wide range of species to better understand coral survival under the predicted rise in sea surface temperatures.
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Affiliation(s)
- Viridiana Avila-Magaña
- grid.29857.310000 0001 2097 4281Biology Department, The Pennsylvania State University, University Park, PA USA ,grid.266190.a0000000096214564Ecology and Evolutionary Biology Department, University of Colorado Boulder, Boulder, CO USA
| | - Bishoy Kamel
- grid.266832.b0000 0001 2188 8502Center for Evolutionary and Theoretical Immunology, University of New Mexico, Albuquerque, NM USA ,grid.184769.50000 0001 2231 4551Present Address: US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA USA
| | - Michael DeSalvo
- grid.266096.d0000 0001 0049 1282School of Natural Sciences, University of California, Merced, CA USA ,grid.418190.50000 0001 2187 0556Thermo Fisher Scientific, Carlsbad, CA USA
| | - Kelly Gómez-Campo
- grid.29857.310000 0001 2097 4281Biology Department, The Pennsylvania State University, University Park, PA USA
| | - Susana Enríquez
- grid.9486.30000 0001 2159 0001Unidad Académica de Sistemas Arrecifales Puerto Morelos, ICMyL, Universidad Nacional Autónoma de México, Cancún, Mexico
| | - Hiroaki Kitano
- grid.452864.9The Systems Biology Institute, Tokyo, Japan ,grid.250464.10000 0000 9805 2626Okinawa Institute of Science and Technology, Okinawa, Japan
| | - Rori V. Rohlfs
- grid.263091.f0000000106792318Department of Biology, San Francisco State University, San Francisco, CA USA
| | - Roberto Iglesias-Prieto
- grid.29857.310000 0001 2097 4281Biology Department, The Pennsylvania State University, University Park, PA USA
| | - Mónica Medina
- grid.29857.310000 0001 2097 4281Biology Department, The Pennsylvania State University, University Park, PA USA
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19
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Curran A, Barnard S. What is the role of zooxanthellae during coral bleaching? Review of zooxanthellae and their response to environmental stress. S AFR J SCI 2021. [DOI: 10.17159/sajs.2021/8369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Coral reefs are diverse and productive but sensitive ecosystems. Due to the impact of climate change, these organisms are in danger of dying out, mainly through the process of coral bleaching, which is the process by which zooxanthellae (algal endosymbionts) are expelled from their respective coral hosts, causing the coral to lose colour and become white. Coral bleaching has been linked to increases in sea surface temperatures as well as an increase in light intensity. We reviewed the different zooxanthellae taxa and their ecological traits, as well as the information available on the protective mechanisms present in zooxanthellae cells when they experience environmental stress conditions, such as temperature fluctuations, specifically concentrating on heat shock proteins and their response to antioxidant stress. The eight clades (A–H) previously recognised were reorganised into seven existing genera. Different zooxanthellae taxa exhibit different ecological traits such as their photosynthetic stress responses to light and temperature. Zooxanthellae have the ability to regulate the number and type of heat shock proteins (Hsps) they produce during a heat response. They can also regulate the host’s respective Hsps. Antioxidant responses that can prevent coral hosts from expelling the zooxanthellae, can be found both within exposed coral tissue and the zooxanthellae cells. Despite the lower likelihood of bleaching in South African coral reefs, genetic engineering presents a useful tool to understand and adapt traits within zooxanthellae genotypes to help mitigate coral bleaching in the future.
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Affiliation(s)
- Anuschka Curran
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Sandra Barnard
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
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20
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Onyango CA, Glassom D, MacDonald A. De novo assembly of the transcriptome of scleractinian coral, Anomastraea irregularis and analyses of its response to thermal stress. Mol Biol Rep 2021; 48:2083-2092. [PMID: 33660094 DOI: 10.1007/s11033-021-06184-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 01/25/2021] [Indexed: 10/22/2022]
Abstract
Rising seawater temperatures cause coral bleaching. The molecular responses of the coral holobiont under stress conditions, determine the success of the symbiosis. Anomastraea irregularis is a hard coral commonly found in the harsh intertidal zones of the south coast of KwaZulu-Natal (KZN), South Africa, where it thrives at the very margins of hard coral distribution in the Western Indian Ocean. To identify the possible molecular and cellular mechanisms underlying its resilience to heat stress, experimental and control nubbins were exposed to temperatures of 29 and 19 °C respectively for 24 h. The transcriptome was assembled de novo from 42.8 million quality controlled 63 bp paired-end short sequence reads obtained via RNA sequencing (RNA-seq). The assembly yielded 333,057 contigs (> 500 bp = 55,626, Largest = 6341 bp N50 = 747 bp). 1362 (1.23%) of the transcripts were significantly differentially expressed between heat stressed and control samples. Log fold change magnitudes among individual genes ranged from - 4.6 to 7.2. Overall, the heat stress response in the A. irregularis constituted a protective response involving up regulation of apoptosis and SUMOylation. Gene ontology (GO) analyses revealed that heat stress in the coral affected the metabolism, protein synthesis, photosynthesis, transport and cytoskeleton. This is the first study to produce a reference transcriptome of this coral species and analyze its response to heat stress. The assembled transcriptome also presents a valuable resource for further transcriptomic and genomic studies.
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Affiliation(s)
- Christine A Onyango
- School of Life Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa. .,School of Natural Sciences, Masinde Muliro University of Science and Technology, Kakamega, 50100, Kenya.
| | - David Glassom
- School of Life Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa
| | - Angus MacDonald
- School of Life Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa
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21
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Clowez S, Renicke C, Pringle JR, Grossman AR. Impact of Menthol on Growth and Photosynthetic Function of Breviolum Minutum (Dinoflagellata, Dinophyceae, Symbiodiniaceae) and Interactions with its Aiptasia Host. JOURNAL OF PHYCOLOGY 2021; 57:245-257. [PMID: 33025575 DOI: 10.1111/jpy.13081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 09/01/2020] [Accepted: 09/19/2020] [Indexed: 06/11/2023]
Abstract
Environmental change, including global warming and chemical pollution, can compromise cnidarian-(e.g., coral-) dinoflagellate symbioses and cause coral bleaching. Understanding the mechanisms that regulate these symbioses will inform strategies for sustaining healthy coral-reef communities. A model system for corals is the symbiosis between the sea anemone Exaiptasia pallida (common name Aiptasia) and its dinoflagellate partners (family Symbiodiniaceae). To complement existing studies of the interactions between these organisms, we examined the impact of menthol, a reagent often used to render cnidarians aposymbiotic, on the dinoflagellate Breviolum minutum, both in culture and in hospite. In both environments, the growth and photosynthesis of this alga were compromised at either 100 or 300 µM menthol. We observed reduction in PSII and PSI functions, the abundances of reaction-center proteins, and, at 300 µM menthol, of total cellular proteins. Interestingly, for free-living algae exposed to 100 µM menthol, an initial decline in growth, photosynthetic activities, pigmentation, and protein abundances reversed after 5-15 d, eventually approaching control levels. This behavior was observed in cells maintained in continuous light, but not in cells experiencing a light-dark regimen, suggesting that B. minutum can detoxify menthol or acclimate and repair damaged photosynthetic complexes in a light- and/or energy-dependent manner. Extended exposures of cultured algae to 300 µM menthol ultimately resulted in algal death. Most symbiotic anemones were also unable to survive this menthol concentration for 30 d. Additionally, cells impaired for photosynthesis by pre-treatment with 300 µM menthol exhibited reduced efficiency in re-populating the anemone host.
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Affiliation(s)
- Sophie Clowez
- Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, California, 94305, USA
| | - Christian Renicke
- Department of Genetics, Stanford University, Stanford, California, 94305, USA
| | - John R Pringle
- Department of Genetics, Stanford University, Stanford, California, 94305, USA
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, California, 94305, USA
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22
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Roles of Si and SiNPs in Improving Thermotolerance of Wheat Photosynthetic Machinery via Upregulation of PsbH, PsbB and PsbD Genes Encoding PSII Core Proteins. HORTICULTURAE 2021. [DOI: 10.3390/horticulturae7020016] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Photosystem II is extremely susceptible to environmental alterations, particularly high temperatures. The maintenance of an efficient photosynthetic system under stress conditions is one of the main issues for plants to attain their required energy. Nowadays, searching for stress alleviators is the main goal for maintaining photosynthetic system productivity and, thereby, crop yield under global climate change. Potassium silicate (K2SiO3, 1.5 mM) and silicon dioxide nanoparticles (SiO2NPs, 1.66 mM) were used to mitigate the negative impacts of heat stress (45 °C, 5 h) on wheat (Triticum aestivum L.) cv. (Shandawelly) seedlings. The results showed that K2SiO3 and SiO2NPs diminished leaf rolling symptoms and electrolyte leakage (EL) of heat-stressed wheat leaves. Furthermore, the maximum quantum yield of photosystem II (Fv/Fm) and the performance index (PIabs), as well as the photosynthetic pigments and organic solutes including soluble sugars, sucrose, and proline accumulation, were increased in K2SiO3 and SiO2NPs stressed leaves. At the molecular level, RT-PCR analysis showed that K2SiO3 and SiO2NPs treatments stimulated the overexpression of PsbH, PsbB, and PsbD genes. Notably, this investigation indicated that K2SiO3 was more effective in improving wheat thermotolerance compared to SiO2NPs. The application of K2SiO3 and SiO2NPs may be one of the proposed approaches to improve crop growth and productivity to tolerate climatic change.
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Gaspar TL, Quimbayo JP, Ozekoski R, Nunes LT, Aued AW, Mendes TC, Garrido AG, Segal B. Severe coral bleaching of Siderastrea stellata at the only atoll in the South Atlantic driven by sequential Marine Heatwaves. BIOTA NEOTROPICA 2021. [DOI: 10.1590/1676-0611-bn-2020-1131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/22/2023]
Abstract
Abstract: Threatened by global warming and extreme climatic events, such as El Niño Southern Oscillation (ENSO) and Marine Heatwaves (MHW), coral reefs worldwide faced the worst bleaching and mortality event between 2014 and 2017, induced by the 2015/2016 ENSO. We evaluated the impacts of ENSO and MHW episodes on bleaching and mortality frequencies of Siderastrea stellata at Rocas Atoll, Southwestern Atlantic, using visual censuses conducted in 2016, 2017 and 2019. Bleaching rate varied significantly along the sampling period (11.71% in 2016, 1.52% in 2017, and 88% in 2019), but mortality was always less than 4%. Bleaching events in Atlantic reefs have been constantly associated with ENSO, until these recent events of the last two years. We suggest that MHW were probably the primary driver of the observed bleaching, especially in 2019, when much higher bleaching rates were observed than in ENSO periods. Although Southwestern Atlantic massive corals are considered more resistant to thermal stress than reefs corals worldwide, the strong events registered since 2019 highlight the need for continuous monitoring to better understand coral bleaching dynamics and improve predictions on the effects of global change in the region.
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Affiliation(s)
| | | | | | | | | | | | | | - Bárbara Segal
- Universidade Federal de Santa Catarina, Brasil; Instituto Coral Vivo, Brasil
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24
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Mason RAB, Wall CB, Cunning R, Dove S, Gates RD. High light alongside elevated P CO2 alleviates thermal depression of photosynthesis in a hard coral ( Pocillopora acuta). ACTA ACUST UNITED AC 2020; 223:223/20/jeb223198. [PMID: 33087470 DOI: 10.1242/jeb.223198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 08/12/2020] [Indexed: 11/20/2022]
Abstract
The absorbtion of human-emitted CO2 by the oceans (elevated P CO2 ) is projected to alter the physiological performance of coral reef organisms by perturbing seawater chemistry (i.e. ocean acidification). Simultaneously, greenhouse gas emissions are driving ocean warming and changes in irradiance (through turbidity and cloud cover), which have the potential to influence the effects of ocean acidification on coral reefs. Here, we explored whether physiological impacts of elevated P CO2 on a coral-algal symbiosis (Pocillopora acuta-Symbiodiniaceae) are mediated by light and/or temperature levels. In a 39 day experiment, elevated P CO2 (962 versus 431 µatm P CO2 ) had an interactive effect with midday light availability (400 versus 800 µmol photons m-2 s-1) and temperature (25 versus 29°C) on areal gross and net photosynthesis, for which a decline at 29°C was ameliorated under simultaneous high-P CO2 and high-light conditions. Light-enhanced dark respiration increased under elevated P CO2 and/or elevated temperature. Symbiont to host cell ratio and chlorophyll a per symbiont increased at elevated temperature, whilst symbiont areal density decreased. The ability of moderately strong light in the presence of elevated P CO2 to alleviate the temperature-induced decrease in photosynthesis suggests that higher substrate availability facilitates a greater ability for photochemical quenching, partially offsetting the impacts of high temperature on the photosynthetic apparatus. Future environmental changes that result in moderate increases in light levels could therefore assist the P. acuta holobiont to cope with the 'one-two punch' of rising temperatures in the presence of an acidifying ocean.
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Affiliation(s)
- Robert A B Mason
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, PO Box 1346, Kāne'ohe, HI 96744, USA .,ARC Centre of Excellence for Coral Reef Studies, and Centre for Marine Science, School of Biological Sciences, University of Queensland, St Lucia, QLD 4072, Australia
| | - Christopher B Wall
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, PO Box 1346, Kāne'ohe, HI 96744, USA.,Pacific Biosciences Research Center, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA
| | - Ross Cunning
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, PO Box 1346, Kāne'ohe, HI 96744, USA.,Daniel P. Haerther Center for Conservation and Research, John G. Shedd Aquarium, Chicago, IL 60605, USA
| | - Sophie Dove
- ARC Centre of Excellence for Coral Reef Studies, and Centre for Marine Science, School of Biological Sciences, University of Queensland, St Lucia, QLD 4072, Australia
| | - Ruth D Gates
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, PO Box 1346, Kāne'ohe, HI 96744, USA
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25
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Chen JH, Chen ST, He NY, Wang QL, Zhao Y, Gao W, Guo FQ. Nuclear-encoded synthesis of the D1 subunit of photosystem II increases photosynthetic efficiency and crop yield. NATURE PLANTS 2020; 6:570-580. [PMID: 32313138 DOI: 10.1038/s41477-020-0629-z] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 02/27/2020] [Indexed: 05/08/2023]
Abstract
In photosynthetic organisms, the photosystem II (PSII) complex is the primary target of thermal damage. Plants have evolved a repair process to prevent the accumulation of damaged PSII. The repair of PSII largely involves de novo synthesis of proteins, particularly the D1 subunit protein encoded by the chloroplast gene psbA. Here we report that the allotropic expression of the psbA complementary DNA driven by a heat-responsive promoter in the nuclear genome sufficiently protects PSII from severe loss of D1 protein and dramatically enhances survival rates of the transgenic plants of Arabidopsis, tobacco and rice under heat stress. Unexpectedly, we found that the nuclear origin supplementation of the D1 protein significantly stimulates transgenic plant growth by enhancing net CO2 assimilation rates with increases in biomass and grain yield. These findings represent a breakthrough in bioengineering plants to achieve efficient photosynthesis and increase crop productivity under normal and heat-stress conditions.
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Affiliation(s)
- Juan-Hua Chen
- National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Si-Ting Chen
- National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Ning-Yu He
- National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Qing-Long Wang
- National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Yao Zhao
- National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wei Gao
- National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fang-Qing Guo
- National Key Laboratory of Plant Molecular Genetics and CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology & Ecology, Chinese Academy of Sciences, Shanghai, China.
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Abstract
Over the last three decades corals have declined precipitously in the Florida Keys. Their population decline has prompted restoration effort. Yet, little effort has been invested in understanding the contemporary niche spaces of coral species, which could assist in prioritizing conservation habitats. We sought to predict the probability of occurrence of 23 coral species, including the critically endangered Acropora cervicornis, using observations at 985 sites from 2011–2015. We ran boosted regression trees to evaluate the relationship between the presence of these corals and eight potential environmental predictors: (i) bathymetry (m), (ii) mean of daily sea surface temperature (SST) (°C), (iii) variance of SST (°C), (iv) range of SST (°C), (v) chlorophyll-a concentration (mg m3), (vi) turbidity (m-1), (vii) wave energy (kJ m-2), and (viii) distance from coast (km). The Marquesas and the lower and upper Florida Keys were predicted to support the most suitable habitats for the 23 coral species examined. A. cervicornis had one of the smallest areas of suitable habitat, which was limited to the lower and upper Florida Keys, the Dry Tortugas, and nearshore Broward-Miami reefs. The best environmental predictors of site occupancy of A. cervicornis were SST range (4–5°C) and turbidity (K490 between 0.15–0.25 m-1). Historically A. cervicornis was reported in clear oligotrophic waters, although the present results find the coral species surviving in nearshore turbid conditions. Nearshore, turbid reefs may shade corals during high-temperature events, and therefore nearshore reefs in south Florida may become important refuges for corals as the ocean temperatures continue to increase.
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27
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Sully S, van Woesik R. Turbid reefs moderate coral bleaching under climate-related temperature stress. GLOBAL CHANGE BIOLOGY 2020; 26:1367-1373. [PMID: 31912964 PMCID: PMC7079097 DOI: 10.1111/gcb.14948] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 11/17/2019] [Accepted: 11/20/2019] [Indexed: 05/12/2023]
Abstract
Thermal-stress events that cause coral bleaching and mortality have recently increased in frequency and severity. Yet few studies have explored conditions that moderate coral bleaching. Given that high light and high ocean temperature together cause coral bleaching, we explore whether corals at turbid localities, with reduced light, are less likely to bleach during thermal-stress events than corals at other localities. We analyzed coral bleaching, temperature, and turbidity data from 3,694 sites worldwide with a Bayesian model and found that Kd 490, a measurement positively related to turbidity, between 0.080 and 0.127 reduced coral bleaching during thermal-stress events. Approximately 12% of the world's reefs exist within this "moderating turbidity" range, and 30% of reefs that have moderating turbidity are in the Coral Triangle. We suggest that these turbid nearshore environments may provide some refuge through climate change, but these reefs will need high conservation status to sustain them close to dense human populations.
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Affiliation(s)
- Shannon Sully
- Institute for Global EcologyFlorida Institute of TechnologyMelbourneFLUSA
| | - Robert van Woesik
- Institute for Global EcologyFlorida Institute of TechnologyMelbourneFLUSA
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28
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Venegas RM, Oliver T, Liu G, Heron SF, Clark SJ, Pomeroy N, Young C, Eakin CM, Brainard RE. The Rarity of Depth Refugia from Coral Bleaching Heat Stress in the Western and Central Pacific Islands. Sci Rep 2019; 9:19710. [PMID: 31873188 PMCID: PMC6928217 DOI: 10.1038/s41598-019-56232-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 11/26/2019] [Indexed: 02/05/2023] Open
Abstract
Some researchers have suggested that corals living in deeper reefs may escape heat stress experienced by shallow corals. We evaluated the potential of deep coral reef refugia from bleaching stress by leveraging a long record of satellite-derived sea surface temperature data with a temporal, spatial, and depth precision of in situ temperature records. We calculated an in situ stress metric using a depth bias-adjusted threshold for 457 coral reef sites among 49 islands in the western and central Pacific Ocean over the period 2001-2017. Analysis of 1,453 heating events found no meaningful depth refuge from heat stress down to 38 m, and no significant association between depth and subsurface heat stress. Further, the surface metric underestimated subsurface stress by an average of 39.3%, across all depths. Combining satellite and in situ temperature data can provide bleaching-relevant heat stress results to avoid misrepresentation of heat stress exposure at shallow reefs.
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Affiliation(s)
- Roberto M Venegas
- Joint Institute for Marine and Atmospheric Research, University of Hawaii at Mānoa, 1000 Pope Road, Honolulu, HI, 96822, USA.
- Pacific Islands Fisheries Science Center, National Marine Fisheries Service, NOAA, 1845 Wasp Boulevard, Building 176, Honolulu, HI, 96818, USA.
| | - Thomas Oliver
- Pacific Islands Fisheries Science Center, National Marine Fisheries Service, NOAA, 1845 Wasp Boulevard, Building 176, Honolulu, HI, 96818, USA.
| | - Gang Liu
- NOAA/NESDIS/STAR Coral Reef Watch, College Park, MD, 20740, USA
- Earth System Science Interdisciplinary Center/Cooperative Institute for Climate and Satellites-Maryland, University of Maryland, 5825 University Research Court, College Park, MD, 20740, USA
| | - Scott F Heron
- NOAA/NESDIS/STAR Coral Reef Watch, College Park, MD, 20740, USA
- Marine Geophysical Laboratory, Physics Department, College of Science, Technology and Engineering, James Cook University, Townsville, QLD, 4811, Australia
| | - S Jeanette Clark
- National Center for Ecological Analysis and Synthesis, University of California Santa Barbara, California, CA, 93101, USA
| | - Noah Pomeroy
- Joint Institute for Marine and Atmospheric Research, University of Hawaii at Mānoa, 1000 Pope Road, Honolulu, HI, 96822, USA
- Pacific Islands Fisheries Science Center, National Marine Fisheries Service, NOAA, 1845 Wasp Boulevard, Building 176, Honolulu, HI, 96818, USA
| | - Charles Young
- Joint Institute for Marine and Atmospheric Research, University of Hawaii at Mānoa, 1000 Pope Road, Honolulu, HI, 96822, USA
- Pacific Islands Fisheries Science Center, National Marine Fisheries Service, NOAA, 1845 Wasp Boulevard, Building 176, Honolulu, HI, 96818, USA
| | - C Mark Eakin
- NOAA/NESDIS/STAR Coral Reef Watch, College Park, MD, 20740, USA
| | - Russell E Brainard
- Pacific Islands Fisheries Science Center, National Marine Fisheries Service, NOAA, 1845 Wasp Boulevard, Building 176, Honolulu, HI, 96818, USA
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29
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Hill LJ, Paradas WC, Willemes MJ, Pereira MG, Salomon PS, Mariath R, Moura RL, Atella GC, Farina M, Amado-Filho GM, Salgado LT. Acidification-induced cellular changes in Symbiodinium isolated from Mussismilia braziliensis. PLoS One 2019; 14:e0220130. [PMID: 31381568 PMCID: PMC6681953 DOI: 10.1371/journal.pone.0220130] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 07/09/2019] [Indexed: 01/27/2023] Open
Abstract
Dinoflagellates from the Symbiodiniaceae family and corals have an ecologically important endosymbiotic relationship. Scleractinian corals cannot survive for long periods without their symbionts. These algae, also known as zooxanthellae, on the other hand, thrives outside the coral cells. The free-living populations of zooxanthellae are essential for the resilience of the coral to environmental stressors such as temperature anomalies and ocean acidification. Yet, little is known about how ocean acidification may affect the free-living zooxanthellae. In this study we aimed to test morphological, physiological and biochemical responses of zooxanthellae from the Symbiodinium genus isolated from the coral Mussismilia braziliensis, endemic to the Brazilian coast, to acidification led by increased atmospheric CO2. We tested whether photosynthetic yield, cell ultrastructure, cell density and lipid profile would change after up to 16 days of exposure to pH 7.5 in an atmospheric pCO2 of 1633 μatm. Photosynthetic yield and cell density were negatively affected and chloroplasts showed vesiculated thylakoids, indicating morphological damage. Moreover, Symbiodinium fatty acid profile drastically changed in acidified condition, showing lower polyunsaturated fatty acids and higher saturated fatty acids contents, when compared to the control, non-acidified condition. These results show that seawater acidification as an only stressor causes significant changes in the physiology, biochemistry and ultrastructure of free-living Symbiodinium.
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Affiliation(s)
- Lilian J Hill
- Diretoria de Pesquisas, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Wladimir C Paradas
- Diretoria de Pesquisas, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maria Julia Willemes
- Diretoria de Pesquisas, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Miria G Pereira
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Paulo S Salomon
- Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Rodrigo Mariath
- Diretoria de Pesquisas, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rodrigo L Moura
- Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Georgia C Atella
- Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Marcos Farina
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Gilberto M Amado-Filho
- Diretoria de Pesquisas, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leonardo T Salgado
- Diretoria de Pesquisas, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil
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Hoepner CM, Abbott CA, Burke da Silva K. The Ecological Importance of Toxicity: Sea Anemones Maintain Toxic Defence When Bleached. Toxins (Basel) 2019; 11:toxins11050266. [PMID: 31083576 PMCID: PMC6563229 DOI: 10.3390/toxins11050266] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/05/2019] [Accepted: 05/08/2019] [Indexed: 12/03/2022] Open
Abstract
Cnidarians are amongst the most venomous animals on the planet. They are also under significant threat due to the impacts of climate change. Corals and anemones undergo climate-induced bleaching during extreme environmental conditions, where a loss of symbiotic photosynthetic algae (zooxanthellae) causes whitening in colour, loss of internal food supply, and reduction in health, which can ultimately lead to death. What has yet to be determined is whether bleaching causes a reduction in the production or quality of venom. In this study, the sea anemone Entacmaea quadricolor was exposed to long-term light-induced bleaching to examine the effect that bleaching has on venom. Venom quality and quantity, as determined through lethality and haemolysis measures and nematocyst production was highly preserved over the five-month imposed bleaching event. Maintenance of venom and nematocyst production, despite a loss of an internal food source provided by endosymbiotic algae, indicates both the ecological importance of maintaining toxicity and a remarkable resilience that anemones have to major environmental stressors.
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Affiliation(s)
- Cassie M Hoepner
- College of Science and Engineering, Flinders University, Adelaide, SA 5001, Australia.
| | - Catherine A Abbott
- College of Science and Engineering, Flinders University, Adelaide, SA 5001, Australia.
| | - Karen Burke da Silva
- College of Science and Engineering, Flinders University, Adelaide, SA 5001, Australia.
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31
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Chakravarti LJ, Negri AP, van Oppen MJH. Thermal and Herbicide Tolerances of Chromerid Algae and Their Ability to Form a Symbiosis With Corals. Front Microbiol 2019; 10:173. [PMID: 30809207 PMCID: PMC6379472 DOI: 10.3389/fmicb.2019.00173] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 01/22/2019] [Indexed: 11/13/2022] Open
Abstract
Reef-building corals form an obligate symbiosis with photosynthetic microalgae in the family Symbiodiniaceae that meet most of their energy requirements. This symbiosis is under threat from the unprecedented rate of ocean warming as well as the simultaneous pressure of local stressors such as poor water quality. Only 1°C above mean summer sea surface temperatures (SSTs) on the Great Barrier Reef (GBR) can trigger the loss of Symbiodiniaceae from the host, and very low concentrations of the most common herbicide, diuron, can disrupt the photosynthetic activity of microalgae. In an era of rapid environmental change, investigation into the assisted evolution of the coral holobiont is underway in an effort to enhance the resilience of corals. Apicomplexan-like microalgae were discovered in 2008 and the Phylum Chromerida (chromerids) was created. Chromerids have been isolated from corals and contain a functional photosynthetic plastid. Their discovery therefore opens a new avenue of research into the use of alternative/additional photosymbionts of corals. However, only two studies to-date have investigated the symbiotic nature of Chromera velia with corals and thus little is known about the coral-chromerid relationship. Furthermore, the response of chromerids to environmental stressors has not been examined. Here we tested the performance of four chromerid strains and the common dinoflagellate symbiont Cladocopium goreaui (formerly Symbiodinium goreaui, ITS2 type C1) in response to elevated temperature, diuron and their combined exposure. Three of the four chromerid strains exhibited high thermal tolerances and two strains showed exceptional herbicide tolerances, greater than observed for any photosynthetic microalgae, including C. goreaui. We also investigated the onset of symbiosis between the chromerids and larvae of two common GBR coral species under ambient and stress conditions. Levels of colonization of coral larvae with the chromerid strains were low compared to colonization with C. goreaui. We did not observe any overall negative or positive larval fitness effects of the inoculation with chromerid algae vs. C. goreaui. However, we cannot exclude the possibility that chromerid algae may have more important roles in later coral life stages and recommend this be the focus of future studies.
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Affiliation(s)
- Leela J. Chakravarti
- Australian Institute of Marine Science, Townsville MC, QLD, Australia
- AIMS@JCU, Australian Institute of Marine Science, College of Marine and Environmental Sciences, James Cook University, Townsville, QLD, Australia
- College of Marine and Environmental Sciences, James Cook University, Townsville, QLD, Australia
| | - Andrew P. Negri
- Australian Institute of Marine Science, Townsville MC, QLD, Australia
| | - Madeleine J. H. van Oppen
- Australian Institute of Marine Science, Townsville MC, QLD, Australia
- School of BioSciences University of Melbourne, Parkville, VIC, Australia
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32
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Woesik RV, Köksal S, Ünal A, Cacciapaglia CW, Randall CJ. Predicting coral dynamics through climate change. Sci Rep 2018; 8:17997. [PMID: 30573804 PMCID: PMC6301976 DOI: 10.1038/s41598-018-36169-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 11/13/2018] [Indexed: 11/09/2022] Open
Abstract
Thermal-stress events are changing the composition of many coral reefs worldwide. Yet, determining the rates of coral recovery and their long-term responses to increasing sea-surface temperatures is challenging. To do so, we first estimated coral recovery rates following past disturbances on reefs in southern Japan and Western Australia. Recovery rates varied between regions, with the reefs in southern Japan showing more rapid recovery rates (intrinsic rate of increase, r = 0.38 year-1) than reefs in Western Australia (r = 0.17 year-1). Second, we input these recovery rates into a novel, nonlinear hybrid-stochastic-dynamical system to predict the responses of Indo-Pacific coral populations to complex inter-annual temperature cycles into the year 2100. The coral recovery rates were overlaid on background increases in global sea-surface temperatures, under three different climate-change scenarios. The models predicted rapid recovery at both localities with the infrequent and low-magnitude temperature anomalies expected under a conservative climate-change scenario, Representative Concentration Pathway (RCP) 4.5. With moderate increases in ocean temperatures (RCP 6.0) the coral populations showed a bimodal response, with model runs showing either recovery or collapse. Under a business-as-usual climate-change scenario (RCP 8.5), with frequent and intense temperature anomalies, coral recovery was unlikely.
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Affiliation(s)
- Robert van Woesik
- Institute for Global Ecology, Florida Institute of Technology 150 West University Boulevard, Melbourne, Florida, 32901, United States of America.
| | - Semen Köksal
- Department of Mathematical Sciences, Florida Institute of Technology 150 West University Boulevard, Melbourne, Florida, 32901, United States of America
| | - Arzu Ünal
- Department of Mathematics, Ankara University, Tandogan, Ankara, 06100, Turkey
| | - Chris W Cacciapaglia
- Institute for Global Ecology, Florida Institute of Technology 150 West University Boulevard, Melbourne, Florida, 32901, United States of America
| | - Carly J Randall
- Institute for Global Ecology, Florida Institute of Technology 150 West University Boulevard, Melbourne, Florida, 32901, United States of America.,Australian Institute of Marine Science, PMB 3, Townsville, Queensland, 4810, Australia
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Hu L, Bi A, Hu Z, Amombo E, Li H, Fu J. Antioxidant Metabolism, Photosystem II, and Fatty Acid Composition of Two Tall Fescue Genotypes With Different Heat Tolerance Under High Temperature Stress. FRONTIERS IN PLANT SCIENCE 2018; 9:1242. [PMID: 30186304 PMCID: PMC6113381 DOI: 10.3389/fpls.2018.01242] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 08/06/2018] [Indexed: 05/25/2023]
Abstract
Tall fescue (Festuca arundinacea Schreb.) is a typical and widely used cool-season turf grass. High temperature is a key factor that limits its utility. The objectives of this study were to investigate the behaviors of fatty acid composition and its gene expression patterns in heat-resistant genotype "TF71" and heat-sensitive genotype "TF133" exposed to heat stress (40/35°C, 14/10 h), and to broaden our comprehension about the relationship between heat tolerance and fatty acid function. The result showed that heat stress increased the malondialdehyde (MDA) content and relative electrolyte leakage (EL), but decreased the level of chlorophyll and the activity of superoxide dismutase (SOD) and peroxidase (POD) when compared to the controls, to a greater extent in "TF133." This result proved that "TF71" had superior high-temperature resistance. Furthermore, comparing the changes in the composition of fatty acid and the expression of the genes involved in its synthesis between the two different genotypes under heat stress, we found that heat stress increased the degree of unsaturation, UFA/SFA, and double bond index (DBI) in "TF71." Moreover, quantitative RT-PCR revealed that heat stress altered the expression of the genes involved in fatty acid synthesis, including ACAC, FabD, FabF, FabH, FabI, and FatA. According to these findings, we can speculate that increasing the unsaturation degree of fatty acid or controlling the equilibrium ratio of UFA/SFA might be closely associated with the improving of the heat resistance in tall fescue.
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Affiliation(s)
- Lianlian Hu
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Aoyue Bi
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhengrong Hu
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Erick Amombo
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Huiying Li
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, China
| | - Jinmin Fu
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, China
- The Institute for Advanced Study in Coastal Ecology, Ludong University, Yantai, China
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Motone K, Takagi T, Aburaya S, Aoki W, Miura N, Minakuchi H, Takeyama H, Nagasaki Y, Shinzato C, Ueda M. Protection of Coral Larvae from Thermally Induced Oxidative Stress by Redox Nanoparticles. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2018; 20:542-548. [PMID: 29705864 DOI: 10.1007/s10126-018-9825-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 04/03/2018] [Indexed: 06/08/2023]
Abstract
Coral reefs are one of the most biologically diverse and economically important ecosystems on earth. However, the destruction of coral reefs has been reported worldwide owing to rising seawater temperature associated with global warming. In this study, we investigated the potential of a redox nanoparticle (RNPO) to scavenge reactive oxygen species (ROS), which are overproduced under heat stress and play a crucial role in causing coral mortality. When reef-building coral (Acropora tenuis) larvae, without algal symbionts, were exposed to thermal stress at 33 °C, RNPO treatment significantly increased the survival rate. Proteome analysis of coral larvae was performed using nano-liquid chromatography-tandem mass spectrometry for the first time. The results revealed that several proteins related to ROS-induced oxidative stress were specifically identified in A. tenuis larvae without RNPO treatment, whereas these proteins were absent in RNPO-treated larvae, which suggested that RNPO effectively scavenged ROS from A. tenuis larvae. Results from this study indicate that RNPO treatment can reduce ROS in aposymbiotic coral larvae and would be a promising approach for protecting corals from thermal stress.
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Affiliation(s)
- Keisuke Motone
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
- Japan Society for the Promotion of Science, Kyoto, 606-8502, Japan
| | - Toshiyuki Takagi
- Japan Society for the Promotion of Science, Kyoto, 606-8502, Japan
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, 277-8564, Japan
| | - Shunsuke Aburaya
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
- Japan Society for the Promotion of Science, Kyoto, 606-8502, Japan
| | - Wataru Aoki
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Natsuko Miura
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | | | - Haruko Takeyama
- Faculty of Science and Engineering, Waseda University, Tokyo, 162-0056, Japan
| | - Yukio Nagasaki
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, 305-8573, Japan
| | - Chuya Shinzato
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, 277-8564, Japan
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, 904-0495, Japan
| | - Mitsuyoshi Ueda
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan.
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Muir PR, Marshall PA, Abdulla A, Aguirre JD. Species identity and depth predict bleaching severity in reef-building corals: shall the deep inherit the reef? Proc Biol Sci 2018; 284:rspb.2017.1551. [PMID: 29021175 DOI: 10.1098/rspb.2017.1551] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 09/11/2017] [Indexed: 01/02/2023] Open
Abstract
Mass bleaching associated with unusually high sea temperatures represents one of the greatest threats to corals and coral reef ecosystems. Deeper reef areas are hypothesized as potential refugia, but the susceptibility of Scleractinian species over depth has not been quantified. During the most severe bleaching event on record, we found up to 83% of coral cover severely affected on Maldivian reefs at a depth of 3-5 m, but significantly reduced effects at 24-30 m. Analysis of 153 species' responses showed depth, shading and species identity had strong, significant effects on susceptibility. Overall, 73.3% of the shallow-reef assemblage had individuals at a depth of 24-30 m with reduced effects, potentially mitigating local extinction and providing a source of recruits for population recovery. Although susceptibility was phylogenetically constrained, species-level effects caused most lineages to contain some partially resistant species. Many genera showed wide variation between species, including Acropora, previously considered highly susceptible. Extinction risk estimates showed species and lineages of concern and those likely to dominate following repeated events. Our results show that deeper reef areas provide refuge for a large proportion of Scleractinian species during severe bleaching events and that the deepest occurring individuals of each population have the greatest potential to survive and drive reef recovery.
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Affiliation(s)
- Paul R Muir
- Biodiversity, Queensland Museum, Townsville, Queensland, 4811, Australia .,Global Change Institute, ARC Centre of Excellence for Environmental Decisions, University of Queensland, Brisbane, Queensland, 4072, Australia
| | - Paul A Marshall
- Centre for Biodiversity and Conservation Science, ARC Centre of Excellence for Environmental Decisions, University of Queensland, Brisbane, Queensland, 4072, Australia.,Reef Ecologic, Townsville, Queensland, Australia
| | - Ameer Abdulla
- Centre for Biodiversity and Conservation Science, ARC Centre of Excellence for Environmental Decisions, University of Queensland, Brisbane, Queensland, 4072, Australia
| | - J David Aguirre
- Institute of Natural and Mathematical Sciences, Massey University, Palmerston North, Auckland 4474, New Zealand
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Brestic M, Zivcak M, Hauptvogel P, Misheva S, Kocheva K, Yang X, Li X, Allakhverdiev SI. Wheat plant selection for high yields entailed improvement of leaf anatomical and biochemical traits including tolerance to non-optimal temperature conditions. PHOTOSYNTHESIS RESEARCH 2018; 136:245-255. [PMID: 29383631 DOI: 10.1007/s11120-018-0486-z] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 01/23/2018] [Indexed: 05/11/2023]
Abstract
Assessment of photosynthetic traits and temperature tolerance was performed on field-grown modern genotype (MG), and the local landrace (LR) of wheat (Triticum aestivum L.) as well as the wild relative species (Aegilops cylindrica Host.). The comparison was based on measurements of the gas exchange (A/ci, light and temperature response curves), slow and fast chlorophyll fluorescence kinetics, and some growth and leaf parameters. In MG, we observed the highest CO2 assimilation rate [Formula: see text] electron transport rate (Jmax) and maximum carboxylation rate [Formula: see text]. The Aegilops leaves had substantially lower values of all photosynthetic parameters; this fact correlated with its lower biomass production. The mesophyll conductance was almost the same in Aegilops and MG, despite the significant differences in leaf phenotype. In contrary, in LR with a higher dry mass per leaf area, the half mesophyll conductance (gm) values indicated more limited CO2 diffusion. In Aegilops, we found much lower carboxylation capacity; this can be attributed mainly to thin leaves and lower Rubisco activity. The difference in CO2 assimilation rate between MG and others was diminished because of its higher mitochondrial respiration activity indicating more intense metabolism. Assessment of temperature response showed lower temperature optimum and a narrow ecological valence (i.e., the range determining the tolerance limits of a species to an environmental factor) in Aegilops. In addition, analysis of photosynthetic thermostability identified the LR as the most sensitive. Our results support the idea that the selection for high yields was accompanied by the increase of photosynthetic productivity through unintentional improvement of leaf anatomical and biochemical traits including tolerance to non-optimal temperature conditions.
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Affiliation(s)
- Marian Brestic
- Department of Plant Physiology, Slovak Agricultural University, Tr. A. Hlinku 2, 949 76, Nitra, Slovakia.
| | - Marek Zivcak
- Department of Plant Physiology, Slovak Agricultural University, Tr. A. Hlinku 2, 949 76, Nitra, Slovakia
| | - Pavol Hauptvogel
- National Agricultural and Food Centre, Research Institute of Plant Production, Piešťany, Slovakia
| | - Svetlana Misheva
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Street, Bldg. 21, 1113, Sofia, Bulgaria
| | - Konstantina Kocheva
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Street, Bldg. 21, 1113, Sofia, Bulgaria
| | - Xinghong Yang
- State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, China
| | - Xiangnan Li
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Suleyman I Allakhverdiev
- Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russia, 127276.
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russia, 142290.
- Department of Plant Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, Russia, 119991.
- Moscow Institute of Physics and Technology, Institutsky lane 9, Dolgoprudny, Moscow Region, Russia, 141700.
- Institute of Molecular Biology and Biotechnology, Azerbaijan National Academy of Sciences, Matbuat Avenue 2a, 1073, Baku, Azerbaijan.
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Remote Sensing of Coral Bleaching Using Temperature and Light: Progress towards an Operational Algorithm. REMOTE SENSING 2017. [DOI: 10.3390/rs10010018] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Zhang L, Hu T, Amombo E, Wang G, Xie Y, Fu J. The Alleviation of Heat Damage to Photosystem II and Enzymatic Antioxidants by Exogenous Spermidine in Tall Fescue. FRONTIERS IN PLANT SCIENCE 2017; 8:1747. [PMID: 29075277 PMCID: PMC5644155 DOI: 10.3389/fpls.2017.01747] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 09/25/2017] [Indexed: 05/23/2023]
Abstract
Tall fescue (Festuca arundinacea Schreb) is a typical cool-season grass that is widely used in turf and pasture. However, high temperature as an abiotic stress seriously affects its utilization. The objective of this study was to explore the effect of spermidine (Spd) on heat stress response of tall fescue. The samples were exposed to 22°C (normal condition) or 44°C (heat stress) for 4 h. The results showed that exogenous Spd partially improved the quality of tall fescue leaves under normal temperature conditions. Nevertheless, after heat stress treatment, exogenous Spd significantly decreased the electrolyte leakage of tall fescue leaves. Spd also profoundly reduced the H2O2 and O2⋅- content and increased antioxidant enzymes activities. In addition, PAs can also regulate antioxidant enzymes activities including SOD, POD, and APX which could help to scavenge ROS. Moreover, application of Spd could also remarkably increase the chlorophyll content and had a positive effect on the chlorophyll α fluorescence transients under high temperature. The Spd reagent enhanced the performance of photosystem II (PSII) as observed by the JIP-test. Under heat stress, the Spd profoundly improved the partial potentials at the steps of energy bifurcations (PIABS and PItotal) and the quantum yields and efficiencies (φP0, δR0, φR0, and γRC). Exogenous Spd could also reduce the specific energy fluxes per QA- reducing PSII reaction center (RC) (TP0/RC and ET0/RC). Additionally, exogenous Spd improved the expression level of psbA and psbB, which encoded the proteins of PSII core reaction center complex. We infer that PAs can stabilize the structure of nucleic acids and protect RNA from the degradation of ribonuclease. In brief, our study indicates that exogenous Spd enhances the heat tolerance of tall fescue by maintaining cell membrane stability, increasing antioxidant enzymes activities, improving PSII, and relevant gene expression.
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Affiliation(s)
- Liang Zhang
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Graduate University of Chinese Academy of Sciences, Beijing, China
| | - Tao Hu
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Erick Amombo
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Graduate University of Chinese Academy of Sciences, Beijing, China
| | - Guangyang Wang
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Graduate University of Chinese Academy of Sciences, Beijing, China
| | - Yan Xie
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Jinmin Fu
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- School of Resources and Environmental Engineering, Ludong University, Yantai, China
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Bellis ES, Denver DR. Natural Variation in Responses to Acute Heat and Cold Stress in a Sea Anemone Model System for Coral Bleaching. THE BIOLOGICAL BULLETIN 2017; 233:168-181. [PMID: 29373064 DOI: 10.1086/694890] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Rising ocean temperatures disrupt the symbiosis between corals and their microalgae, accelerating global decline of coral reef ecosystems. Because of the difficulty of performing laboratory experiments with corals, the sea anemone Aiptasia has emerged as an important model system for molecular studies of coral bleaching and symbiosis. Here, we investigate natural variation in bleaching responses among different genetic lineages of Aiptasia. Both heat- and cold-induced paths to symbiosis breakdown were analyzed. Significant genetic variation in response to acute heat stress was observed, with severe bleaching of two Aiptasia strains from Hawaii but minimal bleaching of strains from the U.S. South Atlantic, including the strain used to generate the Aiptasia reference genome. Both strains from Hawaii hosted Symbiodinium type B1, whereas strains from the U.S. South Atlantic hosted type A4 or B2. In contrast to the results from exposures to acute heat stress, negligible variation was observed in response to a pulsed cold shock despite moderate bleaching across all strains. These results support our hypothesis that bleaching responses to distinct stressors are independent. Our findings emphasize the role of stress regime when predicting adaptive responses of symbiotic cnidarians to changing climates, because genetic variation may exist for some forms of stress-induced bleaching but not others.
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40
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Sekizawa A, Uechi H, Iguchi A, Nakamura T, Kumagai NH, Suzuki A, Sakai K, Nojiri Y. Intraspecific variations in responses to ocean acidification in two branching coral species. MARINE POLLUTION BULLETIN 2017; 122:282-287. [PMID: 28655461 DOI: 10.1016/j.marpolbul.2017.06.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 06/17/2017] [Accepted: 06/20/2017] [Indexed: 06/07/2023]
Abstract
Ocean acidification is widely recognised to have a negative impact on marine calcifying organisms by reducing calcifications, but controversy remains over whether such organisms could cope with ocean acidification within a range of phenotypic plasticity and/or adapt to future acidifying ocean. We performed a laboratory rearing experiment using clonal fragments of the common branching corals Montipora digitata and Porites cylindrica under control and acidified seawater (lower pH) conditions (approximately 400 and 900μatm pCO2, respectively) and evaluated the intraspecific variations in their responses to ocean acidification. Intra- and interspecific variations in calcification and photosynthetic efficiency were evident according to both pCO2 conditions and colony, indicating that responses to acidification may be individually variable at the colony level. Our results suggest that some corals may cope with ocean acidification within their present genotypic composition by adaptation through phenotypic plasticity, while others may be placed under selective pressures resulting in population alteration.
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Affiliation(s)
- Ayami Sekizawa
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
| | - Hikaru Uechi
- Department of Bioresources Engineering, National Institute of Technology, Okinawa College, 905 Henoko, Nago-City, Okinawa 905-2192, Japan
| | - Akira Iguchi
- Department of Bioresources Engineering, National Institute of Technology, Okinawa College, 905 Henoko, Nago-City, Okinawa 905-2192, Japan.
| | - Takashi Nakamura
- Faculty of Science, University of the Ryukyus, Nishihara, Okinawa 903-0213, Japan
| | - Naoki H Kumagai
- Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan
| | - Atsushi Suzuki
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8567, Japan
| | - Kazuhiko Sakai
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
| | - Yukihiro Nojiri
- Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan
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van Woesik R, Ripple K, Miller SL. Macroalgae reduces survival of nursery-rearedAcroporacorals in the Florida reef tract. Restor Ecol 2017. [DOI: 10.1111/rec.12590] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Robert van Woesik
- Department of Biological Sciences; Florida Institute of Technology, 150 West University Boulevard; Melbourne FL 32901 U.S.A
| | - Kayla Ripple
- Science Program, Coral Restoration Foundation, 5 Seagate Boulevard; Key Largo FL 33037 U.S.A
| | - Steven L. Miller
- Halmos College of Natural Sciences and Oceanography; Nova Southeastern University, 8000 North Ocean Drive; Dania Beach FL 33314 U.S.A
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Chen K, Zhang M, Zhu H, Huang M, Zhu Q, Tang D, Han X, Li J, Sun J, Fu J. Ascorbic Acid Alleviates Damage from Heat Stress in the Photosystem II of Tall Fescue in Both the Photochemical and Thermal Phases. FRONTIERS IN PLANT SCIENCE 2017; 8:1373. [PMID: 28848577 PMCID: PMC5550716 DOI: 10.3389/fpls.2017.01373] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 07/24/2017] [Indexed: 05/09/2023]
Abstract
L-Ascorbate (Asc) plays important roles in plant development, hormone signaling, the cell cycle and cellular redox system, etc. The higher content of Asc in plant chloroplasts indicates its important role in the photosystem. The objective of this study was to study the roles of Asc in tall fescue leaves against heat stress. After a heat stress treatment, we observed a lower value of the maximum quantum yield for primary photochemistry (φPo), which reflects the inhibited activity of the photochemical phase of photosystem II (PSII). Moreover, we observed a higher value of efficiency of electron transfer from QB to photosystem I acceptors (δR0), which reflects elevated activity of the thermal phase of the photosystem of the tall fescue. The addition of Asc facilitate the behavior of the photochemical phase of the PSII by lowering the ROS content as well as that of the alternative electron donor to provide electron to the tyrosine residue of the D1 protein. Additionally, exogenous Asc reduces the activity of the thermal phase of the photosystem, which could contribute to the limitation of energy input into the photosystem in tall fescue against heat stress. Synthesis of the Asc increased under heat stress treatment. However, under heat stress this regulation does not occur at the transcription level and requires further study.
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Affiliation(s)
- Ke Chen
- College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of SciencesWuhan, China
- Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
| | - Minna Zhang
- College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
| | - Huihui Zhu
- College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
| | - Meiyu Huang
- College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
| | - Qing Zhu
- Wuhan Kaidi Electric Power Environmental Co., Ltd.Wuhan, China
| | - Diyong Tang
- College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
| | - Xiaole Han
- College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
- Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
| | - Jinlin Li
- Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
| | - Jie Sun
- College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
- Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, College of Resources and Environmental Science, South-Central University for NationalitiesWuhan, China
| | - Jinmin Fu
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of SciencesWuhan, China
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Seasonal variation modulates coral sensibility to heat-stress and explains annual changes in coral productivity. Sci Rep 2017; 7:4937. [PMID: 28694432 PMCID: PMC5504023 DOI: 10.1038/s41598-017-04927-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 05/23/2017] [Indexed: 01/25/2023] Open
Abstract
The potential effects of seasonal acclimatization on coral sensitivity to heat-stress, has received limited attention despite differing bleaching thresholds for summer and winter. In this study, we examined the response of two contrasting phenotypes, termed winter and summer, of four Caribbean reef corals to similar light and heat-stress levels. The four species investigated were categorized into two groups: species with the ability to harbour large number of symbionts, Orbicella annularis and O. faveolata, and species with reduced symbiont density (Montastraea cavernosa and Pseudodiploria strigosa). The first group showed higher capacity to enhance photosynthetic rates per area (Pmax), while Pmax enhancement in the second group was more dependent on Symbiodinium performance (Psym). In summer all four species presented higher productivity, but also higher sensitivity to lose coral photosynthesis under heat-stress. In contrast, corals in winter exhibit symbionts with higher capacity to photoacclimate to the increased levels of light-stress elicited by heat-stress. Overall, our study supports the importance of the acclimatory coral condition in addition to the previous thermal history, to determine the severity of the impact of heat-stress on coral physiology, but also the dependence of this response on the particular structural and functional traits of the species.
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Wang F, Wang C, Zou T, Xu N, Sun X. Comparative transcriptional profiling of Gracilariopsis lemaneiformis in response to salicylic acid- and methyl jasmonate-mediated heat resistance. PLoS One 2017; 12:e0176531. [PMID: 28464018 PMCID: PMC5413009 DOI: 10.1371/journal.pone.0176531] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 04/12/2017] [Indexed: 11/30/2022] Open
Abstract
Culturing the economically important macroalga Gracilariopsis lemaneiformis (Rhodophyta) is limited due to the high temperatures in the summertime on the southern Chinese coast. Previous studies have demonstrated that two phytohormones, salicylic acid (SA) and methyl jasmonate (MJ), can alleviate the adverse effects of high-temperature stress on Gp. lemaneiformis. To elucidate the molecular mechanisms underlying SA- and MJ-mediated heat tolerance, we performed comprehensive analyses of transcriptome-wide gene expression profiles using RNA sequencing (RNA-seq) technology. A total of 14,644 unigenes were assembled, and 10,501 unigenes (71.71%) were annotated to the reference databases. In the SA, MJ and SA/MJ treatment groups, 519, 830, and 974 differentially expressed unigenes were detected, respectively. Unigenes related to photosynthesis and glycometabolism were enriched by SA, while unigenes associated with glycometabolism, protein synthesis, heat shock and signal transduction were increased by MJ. A crosstalk analysis revealed that 216 genes were synergistically regulated, while 18 genes were antagonistically regulated by SA and MJ. The results indicated that the two phytohormones could mitigate the adverse effects of heat on multiple pathways, and they predominantly acted synergistically to resist heat stress. These results will provide new insights into how SA and MJ modulate the molecular mechanisms that counteract heat stress in algae.
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Affiliation(s)
- Fangjun Wang
- School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, China
- Key Laboratory of Marine Biotechnology of Zhejiang Province, Ningbo, China
| | - Chongbin Wang
- School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, China
- Key Laboratory of Marine Biotechnology of Zhejiang Province, Ningbo, China
| | - Tonglei Zou
- School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, China
- Key Laboratory of Marine Biotechnology of Zhejiang Province, Ningbo, China
| | - Nianjun Xu
- School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, China
- Key Laboratory of Marine Biotechnology of Zhejiang Province, Ningbo, China
| | - Xue Sun
- School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, China
- Key Laboratory of Marine Biotechnology of Zhejiang Province, Ningbo, China
- * E-mail:
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45
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Pontasch S, Fisher PL, Krueger T, Dove S, Hoegh-Guldberg O, Leggat W, Davy SK. Photoacclimatory and photoprotective responses to cold versus heat stress in high latitude reef corals. JOURNAL OF PHYCOLOGY 2017; 53:308-321. [PMID: 27870065 DOI: 10.1111/jpy.12492] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 09/13/2016] [Indexed: 06/06/2023]
Abstract
Corals at the world's southernmost coral reef of Lord Howe Island (LHI) experience large temperature and light fluctuations and need to deal with periods of cold temperature (<18°C), but few studies have investigated how corals are able to cope with these conditions. Our study characterized the response of key photophysiological parameters, as well as photoacclimatory and photoprotective pigments (chlorophylls, xanthophylls, and β-carotene), to short-term (5-d) cold stress (~15°C; 7°C below control) in three LHI coral species hosting distinct Symbiodinium ITS2 types, and compared the coral-symbiont response to that under elevated temperature (~29°C; 7°C above control). Under cold stress, Stylophora sp. hosting Symbiodinium C118 showed the strongest effects with regard to losses of photochemical performance and symbionts. Pocillopora damicornis hosting Symbiodinium C100/C118 showed less severe bleaching responses to reduced temperature than to elevated temperature, while Porites heronensis hosting Symbiodinium C111* withstood both reduced and elevated temperature. Under cold stress, photoprotection in the form of xanthophyll de-epoxidation increased in unbleached P. heronensis (by 178%) and bleached Stylophora sp. (by 225%), while under heat stress this parameter increased in unbleached P. heronensis (by 182%) and in bleached P. damicornis (by 286%). The xanthophyll pool size was stable in all species at all temperatures. Our comparative study demonstrates high variability in the bleaching vulnerability of these coral species to low and high thermal extremes and shows that this variability is not solely determined by the ability to activate xanthophyll de-epoxidation.
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Affiliation(s)
- Stefanie Pontasch
- School of Biological Sciences, Victoria University of Wellington, Wellington, 6140, New Zealand
| | - Paul L Fisher
- School of Biological Sciences, Victoria University of Wellington, Wellington, 6140, New Zealand
| | - Thomas Krueger
- School of Biological Sciences, Victoria University of Wellington, Wellington, 6140, New Zealand
- Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering (ENAC), Ècole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Sophie Dove
- School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Ove Hoegh-Guldberg
- Global Change Institute, University of University of Queensland, Brisbane, QLD, 4072, Australia
| | - William Leggat
- The College of Public Health, Medical and Veterinary Sciences & ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, 4810, Australia
| | - Simon K Davy
- School of Biological Sciences, Victoria University of Wellington, Wellington, 6140, New Zealand
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46
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Levy O, Karako-Lampert S, Waldman Ben-Asher H, Zoccola D, Pagès G, Ferrier-Pagès C. Molecular assessment of the effect of light and heterotrophy in the scleractinian coral Stylophora pistillata. Proc Biol Sci 2017; 283:rspb.2015.3025. [PMID: 27122555 DOI: 10.1098/rspb.2015.3025] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/31/2016] [Indexed: 12/18/2022] Open
Abstract
Corals acquire nutrients via the transfer of photosynthates by their endosymbionts (autotrophy), or via zooplankton predation by the animal (heterotrophy). During stress events, corals lose their endosymbionts, and undergo starvation, unless they increase their heterotrophic capacities. Molecular mechanisms by which heterotrophy sustains metabolism in stressed corals remain elusive. Here for the first time, to the best of our knowledge, we identified specific genes expressed in heterotrophically fed and unfed colonies of the scleractinian coral Stylophora pistillata, maintained under normal and light-stress conditions. Physiological parameters and gene expression profiling demonstrated that fed corals better resisted stress than unfed ones by exhibiting less oxidative damage and protein degradation. Processes affected in light-stressed unfed corals (HLU), were related to energy and metabolite supply, carbohydrate biosynthesis, ion and nutrient transport, oxidative stress, Ca(2+) homeostasis, metabolism and calcification (carbonic anhydrases, calcium-transporting ATPase, bone morphogenetic proteins). Two genes (cp2u1 and cp1a2), which belong to the cytochrome P450 superfamily, were also upregulated 249 and 10 times, respectively, in HLU corals. In contrast, few of these processes were affected in light-stressed fed corals (HLF) because feeding supplied antioxidants and energetic molecules, which help repair oxidative damage. Altogether, these results show that heterotrophy helps prevent the cascade of metabolic problems downstream of oxidative stress.
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Affiliation(s)
- Oren Levy
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Sarit Karako-Lampert
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Hiba Waldman Ben-Asher
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Didier Zoccola
- Centre Scientifique de Monaco, 8 quai Antoine 1er, 98000 Monaco, Monaco
| | - Gilles Pagès
- Université de Nice-Sophia Antipolis, Institut de Recherche sur le Cancer et le Veillissement, IRCAN, CNRS-UMR 7284, INSERM U1081, Nice, France
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Wangpraseurt D, Holm JB, Larkum AWD, Pernice M, Ralph PJ, Suggett DJ, Kühl M. In vivo Microscale Measurements of Light and Photosynthesis during Coral Bleaching: Evidence for the Optical Feedback Loop? Front Microbiol 2017; 8:59. [PMID: 28174567 PMCID: PMC5258690 DOI: 10.3389/fmicb.2017.00059] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 01/09/2017] [Indexed: 12/21/2022] Open
Abstract
Climate change-related coral bleaching, i.e., the visible loss of zooxanthellae from the coral host, is increasing in frequency and extent and presents a major threat to coral reefs globally. Coral bleaching has been proposed to involve accelerating light stress of their microalgal endosymbionts via a positive feedback loop of photodamage, symbiont expulsion and excess in vivo light exposure. To test this hypothesis, we used light and O2 microsensors to characterize in vivo light exposure and photosynthesis of Symbiodinium during a thermal stress experiment. We created tissue areas with different densities of Symbiodinium cells in order to understand the optical properties and light microenvironment of corals during bleaching. Our results showed that in bleached Pocillopora damicornis corals, Symbiodinium light exposure was up to fivefold enhanced relative to healthy corals, and the relationship between symbiont loss and light enhancement was well-described by a power-law function. Cell-specific rates of Symbiodinium gross photosynthesis and light respiration were enhanced in bleached P. damicornis compared to healthy corals, while areal rates of net photosynthesis decreased. Symbiodinium light exposure in Favites sp. revealed the presence of low light microniches in bleached coral tissues, suggesting that light scattering in thick coral tissues can enable photoprotection of cryptic symbionts. Our study provides evidence for the acceleration of in vivo light exposure during coral bleaching but this optical feedback mechanism differs between coral hosts. Enhanced photosynthesis in relation to accelerating light exposure shows that coral microscale optics exerts a key role on coral photophysiology and the subsequent degree of radiative stress during coral bleaching.
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Affiliation(s)
- Daniel Wangpraseurt
- Marine Biological Section, Department of Biology, University of CopenhagenHelsingør, Denmark; Climate Change Cluster, Department of Environmental Sciences, University of Sydney, SydneyNSW, Australia
| | - Jacob B Holm
- Marine Biological Section, Department of Biology, University of Copenhagen Helsingør, Denmark
| | - Anthony W D Larkum
- Climate Change Cluster, Department of Environmental Sciences, University of Sydney, Sydney NSW, Australia
| | - Mathieu Pernice
- Climate Change Cluster, Department of Environmental Sciences, University of Sydney, Sydney NSW, Australia
| | - Peter J Ralph
- Climate Change Cluster, Department of Environmental Sciences, University of Sydney, Sydney NSW, Australia
| | - David J Suggett
- Climate Change Cluster, Department of Environmental Sciences, University of Sydney, Sydney NSW, Australia
| | - Michael Kühl
- Marine Biological Section, Department of Biology, University of CopenhagenHelsingør, Denmark; Climate Change Cluster, Department of Environmental Sciences, University of Sydney, SydneyNSW, Australia
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Ueno M, Sae-Tang P, Kusama Y, Hihara Y, Matsuda M, Hasunuma T, Nishiyama Y. Moderate Heat Stress Stimulates Repair of Photosystem II During Photoinhibition in Synechocystis sp. PCC 6803. PLANT & CELL PHYSIOLOGY 2016; 57:2417-2426. [PMID: 27565206 DOI: 10.1093/pcp/pcw153] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 08/22/2016] [Indexed: 06/06/2023]
Abstract
Examination of the effects of high temperature on the photoinhibition of photosystem II (PSII) in the cyanobacterium Synechocystis sp. PCC 6803 revealed that the extent of photoinhibition of PSII was lower at moderately high temperatures (35-42 °C) than at 30 °C. Photodamage to PSII, as determined in the presence of chloramphenicol, which blocks the repair of PSII, was accelerated at the moderately high temperatures but the effects of repair were greater than those of photodamage. The synthesis de novo of the D1 protein, which is essential for the repair of PSII, was enhanced at 38 °C. Electron transport and the synthesis of ATP were also enhanced at 38 °C, while levels of reactive oxygen species fell. Inhibition of the Calvin-Benson cycle with glycolaldehyde abolished the enhancement of repair of PSII at 38 °C, suggesting that an increase in the activity of the Calvin-Benson cycle might be required for the enhancement of repair at moderately high temperatures. The synthesis de novo of metabolic intermediates of the Calvin-Benson cycle, such as 3-phosphoglycerate, was also enhanced at 38 °C. We propose that moderate heat stress might enhance the repair of PSII by stimulating the synthesis of ATP and depressing the production of reactive oxygen species, via the stimulation of electron transport and suppression of the accumulation of excess electrons on the acceptor side of photosystem I, which might be driven by an increase in the activity of the Calvin-Benson cycle.
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Affiliation(s)
- Mamoru Ueno
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Penporn Sae-Tang
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Yuri Kusama
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Yukako Hihara
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
- Institute for Environmental Science and Technology, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Mami Matsuda
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe 657-8501, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe 657-8501, Japan
| | - Yoshitaka Nishiyama
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
- Institute for Environmental Science and Technology, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
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49
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Humanes A, Noonan SHC, Willis BL, Fabricius KE, Negri AP. Cumulative Effects of Nutrient Enrichment and Elevated Temperature Compromise the Early Life History Stages of the Coral Acropora tenuis. PLoS One 2016; 11:e0161616. [PMID: 27575699 PMCID: PMC5004850 DOI: 10.1371/journal.pone.0161616] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 08/09/2016] [Indexed: 11/18/2022] Open
Abstract
Inshore coral reefs are experiencing the combined pressures of excess nutrient availability associated with coastal activities and warming seawater temperatures. Both pressures are known to have detrimental effects on the early life history stages of hard corals, but studies of their combined effects on early demographic stages are lacking. We conducted a series of experiments to test the combined effects of nutrient enrichment (three levels) and elevated seawater temperature (up to five levels) on early life history stages of the inshore coral Acropora tenuis, a common species in the Indo-Pacific and Red Sea. Gamete fertilization, larval survivorship and larval settlement were all significantly reduced as temperature increased, but only fertilization was further affected by simultaneous nutrient enrichment. Combined high temperatures and nutrient enrichment affected fertilization in an additive manner, whereas embryo abnormalities increased synergistically. Higher than normal temperatures (32°C) increased coral juvenile growth rates 1.6-fold, but mortality also increased by 50%. The co-occurrence of nutrient enrichment with high temperatures reduced juvenile mortality to 36%, ameliorating temperature stress (antagonistic interaction). Overall, the types of effect (additive vs synergistic or antagonistic) and their magnitude varied among life stages. Gamete and embryo stages were more affected by temperature stress and, in some cases, also by nutrient enrichment than juveniles. The data suggest that coastal runoff events might exacerbate the impacts of warming temperatures on fertilization if these events co-occur during corals spawning. The cumulative impacts of simultaneous exposure to nutrient enrichment and elevated temperatures over all early life history stages increases the likelihood for failure of larval supply and recruitment for this coral species. Our results suggest that improving the water quality of river discharges into coastal areas might help to enhance the thermal tolerances of early life history stages in this common coral species.
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Affiliation(s)
- Adriana Humanes
- ARC Centre of Excellence for Coral Reef Studies, and College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland, Australia
- Australian Institute of Marine Science, Townsville, Queensland, Australia
- * E-mail:
| | - Sam H. C. Noonan
- Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Bette L. Willis
- ARC Centre of Excellence for Coral Reef Studies, and College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland, Australia
| | | | - Andrew P. Negri
- Australian Institute of Marine Science, Townsville, Queensland, Australia
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50
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Seveso D, Montano S, Strona G, Orlandi I, Galli P, Vai M. Hsp60 expression profiles in the reef-building coral Seriatopora caliendrum subjected to heat and cold shock regimes. MARINE ENVIRONMENTAL RESEARCH 2016; 119:1-11. [PMID: 27183199 DOI: 10.1016/j.marenvres.2016.05.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/02/2016] [Accepted: 05/07/2016] [Indexed: 06/05/2023]
Abstract
Climate changes have increased the intensity/frequency of extreme thermal events, which represent serious threats to the health of reef-building corals. Since the vulnerability of corals exposed to thermal stresses are related to their ability to regulate Heat shock proteins (Hsps), we have analyzed together the time related expression profiles of the mitochondrial Hsp60 and the associated changes in tissue pigmentation in Seriatopora caliendrum subjected to 48 h of heat and cold treatments characterized by moderate (±2 °C) and severe (±6 °C) shocks. For the first time, an Hsp60 response was observed in a scleractinian coral exposed to cold stresses. Furthermore, the Hsp60 modulations and the changes in the tissue coloration were found to be specific for each treatment. A strong down-regulation at the end of the treatments was observed following both the severe shocks, but only the severe heat stress led to bleaching in concert with the lowest levels of Hsp60, suggesting that a severe heat shock can be more deleterious than an exposure to a severe cold temperature. On the contrary, a moderate cold stress seems to be more harmful than a moderate temperature increase, which could allow coral acclimation. Our results can provide a potential framework for understanding the physiological tolerance of corals under possible future climate changes.
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Affiliation(s)
- Davide Seveso
- Department of Biotechnologies and Biosciences, University of Milan - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy; MaRHE Centre (Marine Research and High Education Centre), Magoodhoo Island, Faafu Atoll, Maldives.
| | - Simone Montano
- Department of Biotechnologies and Biosciences, University of Milan - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy; MaRHE Centre (Marine Research and High Education Centre), Magoodhoo Island, Faafu Atoll, Maldives
| | - Giovanni Strona
- European Commission, Joint Research Centre, Institute for Environment and Sustainability, Via E. Fermi 2749, I-21027, Ispra, Italy
| | - Ivan Orlandi
- Department of Biotechnologies and Biosciences, University of Milan - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
| | - Paolo Galli
- Department of Biotechnologies and Biosciences, University of Milan - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy; MaRHE Centre (Marine Research and High Education Centre), Magoodhoo Island, Faafu Atoll, Maldives
| | - Marina Vai
- Department of Biotechnologies and Biosciences, University of Milan - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
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