1
|
Deore P, Tsang Min Ching SJ, Nitschke MR, Rudd D, Brumley DR, Hinde E, Blackall LL, van Oppen MJH. Unique photosynthetic strategies employed by closely related Breviolum minutum strains under rapid short-term cumulative heat stress. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:4005-4023. [PMID: 38636949 PMCID: PMC11233414 DOI: 10.1093/jxb/erae170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 04/17/2024] [Indexed: 04/20/2024]
Abstract
The thermal tolerance of symbiodiniacean photo-endosymbionts largely underpins the thermal bleaching resilience of their cnidarian hosts such as corals and the coral model Exaiptasia diaphana. While variation in thermal tolerance between species is well documented, variation between conspecific strains is understudied. We compared the thermal tolerance of three closely related strains of Breviolum minutum represented by two internal transcribed spacer region 2 profiles (one strain B1-B1o-B1g-B1p and the other two strains B1-B1a-B1b-B1g) and differences in photochemical and non-photochemical quenching, de-epoxidation state of photopigments, and accumulation of reactive oxygen species under rapid short-term cumulative temperature stress (26-40 °C). We found that B. minutum strains employ distinct photoprotective strategies, resulting in different upper thermal tolerances. We provide evidence for previously unknown interdependencies between thermal tolerance traits and photoprotective mechanisms that include a delicate balancing of excitation energy and its dissipation through fast relaxing and state transition components of non-photochemical quenching. The more thermally tolerant B. minutum strain (B1-B1o-B1g-B1p) exhibited an enhanced de-epoxidation that is strongly linked to the thylakoid membrane melting point and possibly membrane rigidification minimizing oxidative damage. This study provides an in-depth understanding of photoprotective mechanisms underpinning thermal tolerance in closely related strains of B. minutum.
Collapse
Affiliation(s)
- Pranali Deore
- School of BioSciences, The University of Melbourne, Parkville 3010, Victoria, Australia
| | | | - Matthew R Nitschke
- Australian Institute of Marine Science, Townsville 4810, Queensland, Australia
- School of Biological Sciences, Victoria University of Wellington, Wellington 6102, New Zealand
| | - David Rudd
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Douglas R Brumley
- School of Mathematics and Statistics, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Elizabeth Hinde
- School of Physics, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Linda L Blackall
- School of BioSciences, The University of Melbourne, Parkville 3010, Victoria, Australia
| | - Madeleine J H van Oppen
- School of BioSciences, The University of Melbourne, Parkville 3010, Victoria, Australia
- Australian Institute of Marine Science, Townsville 4810, Queensland, Australia
| |
Collapse
|
2
|
Shoguchi E. Gene clusters for biosynthesis of mycosporine-like amino acids in dinoflagellate nuclear genomes: Possible recent horizontal gene transfer between species of Symbiodiniaceae (Dinophyceae). JOURNAL OF PHYCOLOGY 2022; 58:1-11. [PMID: 34699617 PMCID: PMC9298759 DOI: 10.1111/jpy.13219] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 10/01/2021] [Accepted: 10/12/2021] [Indexed: 05/12/2023]
Abstract
Global warming increases the temperature of the ocean surface, which can disrupt dinoflagellate-coral symbioses and result in coral bleaching. Photosynthetic dinoflagellates of the family Symbiodiniaceae include bleaching-tolerant and bleaching-sensitive coral symbionts. Therefore, understanding the molecular mechanisms for changing symbiont diversity is potentially useful to assist recovery of coral holobionts (corals and their associated microbes, including multiple species of Symbiodiniaceae), although sexual reproduction has not been observed in the Symbiodiniaceae. Recent molecular phylogenetic analyses estimate that the Symbiodiniaceae appeared 160 million years ago and diversified into 15 groups, five genera of which now have available draft genomes (i.e., Symbiodinium, Durusdinium, Breviolum, Fugacium, and Cladocopium). Comparative genomic analyses have suggested that crown groups have fewer gene families than early-diverging groups, although many genes that were probably acquired via gene duplications and horizontal gene transfers (HGTs) have been found in each decoded genome. Because UV stress is likely a contributor to coral bleaching, and because the highly conserved gene cluster for mycosporine-like amino acid (MAA) biosynthesis has been found in thermal-tolerant symbiont genomes, I reviewed genomic features of the Symbiodiniaceae, focusing on possible acquisition of a biosynthetic gene cluster for MAAs, which absorb UV radiation. On the basis of highly conserved noncoding sequences, I hypothesized that HGTs have occurred among members of the Symbiodiniaceae and have contributed to the diversification of Symbiodiniaceae-host relationships. Finally, I proposed that bleaching tolerance may be strengthened by multiple MAAs from both symbiotic dinoflagellates and corals.
Collapse
Affiliation(s)
- Eiichi Shoguchi
- Marine Genomics UnitOkinawa Institute of Science and Technology Graduate UniversityOnnaOkinawa904‐0495Japan
| |
Collapse
|
3
|
Chen Z, Grossfurthner L, Loxterman JL, Masingale J, Richardson BA, Seaborn T, Smith B, Waits LP, Narum SR. Applying genomics in assisted migration under climate change: Framework, empirical applications, and case studies. Evol Appl 2022; 15:3-21. [PMID: 35126645 PMCID: PMC8792483 DOI: 10.1111/eva.13335] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 11/18/2021] [Accepted: 12/01/2021] [Indexed: 12/01/2022] Open
Abstract
The rate of global climate change is projected to outpace the ability of many natural populations and species to adapt. Assisted migration (AM), which is defined as the managed movement of climate-adapted individuals within or outside the species ranges, is a conservation option to improve species' adaptive capacity and facilitate persistence. Although conservation biologists have long been using genetic tools to increase or maintain diversity of natural populations, genomic techniques could add extra benefit in AM that include selectively neutral and adaptive regions of the genome. In this review, we first propose a framework along with detailed procedures to aid collaboration among scientists, agencies, and local and regional managers during the decision-making process of genomics-guided AM. We then summarize the genomic approaches for applying AM, followed by a literature search of existing incorporation of genomics in AM across taxa. Our literature search initially identified 729 publications, but after filtering returned only 50 empirical studies that were either directly applied or considered genomics in AM related to climate change across taxa of plants, terrestrial animals, and aquatic animals; 42 studies were in plants. This demonstrated limited application of genomic methods in AM in organisms other than plants, so we provide further case studies as two examples to demonstrate the negative impact of climate change on non-model species and how genomics could be applied in AM. With the rapidly developing sequencing technology and accumulating genomic data, we expect to see more successful applications of genomics in AM, and more broadly, in the conservation of biodiversity.
Collapse
Affiliation(s)
- Zhongqi Chen
- Aquaculture Research InstituteUniversity of IdahoHagermanIdahoUSA
| | - Lukas Grossfurthner
- Bioinformatics and Computational Biology Graduate ProgramUniversity of IdahoHagermanIdahoUSA
| | - Janet L. Loxterman
- Department of Biological SciencesIdaho State UniversityPocatelloIdahoUSA
| | | | | | - Travis Seaborn
- Department of Fish and Wildlife ResourcesUniversity of IdahoMoscowIdahoUSA
| | - Brandy Smith
- Department of Biological SciencesIdaho State UniversityPocatelloIdahoUSA
| | - Lisette P. Waits
- Department of Fish and Wildlife ResourcesUniversity of IdahoMoscowIdahoUSA
| | - Shawn R. Narum
- Columbia River Inter‐Tribal Fish CommissionHagermanIdahoUSA
| |
Collapse
|
4
|
Sánchez-Suárez J, Garnica-Agudelo M, Villamil L, Díaz L, Coy-Barrera E. Bioactivity and Biotechnological Overview of Naturally Occurring Compounds from the Dinoflagellate Family Symbiodiniaceae: A Systematic Review. ScientificWorldJournal 2021; 2021:1983589. [PMID: 34955690 PMCID: PMC8709762 DOI: 10.1155/2021/1983589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/27/2021] [Indexed: 11/17/2022] Open
Abstract
Marine invertebrates are a significant source of biologically active compounds. Recent studies have highlighted the role of microbiota associated with marine invertebrates in the production of bioactive compounds. Corals and sponges are the main marine invertebrates producing bioactive substances, and Symbiodiniaceae dinoflagellates are well-recognized endosymbionts with corals and sponges playing vital functions. The biological properties of Symbiodiniaceae-derived compounds have garnered attention in the past decades owing to their ecological implications and potentiality for bioprospecting initiatives. This study aims to systematically review studies on bioactivities and potential biotechnological applications of Symbiodiniaceae-derived compounds. The PRISMA guidelines were followed. Our study showed that anti-inflammatory and vasoconstrictive activities of Symbiodiniaceae-derived compounds have been the most investigated. However, very few studies have been published, with in vitro culturing of Symbiodiniaceae being the most significant challenge. Therefore, we surveyed for the metabolites reported so far, analyzed their chemodiversity, and discussed approaches to overcome culturing-related limitations.
Collapse
Affiliation(s)
- Jeysson Sánchez-Suárez
- Bioprospecting Research Group, School of Engineering, Universidad de La Sabana, Chía, Colombia
| | - Mariana Garnica-Agudelo
- Bioprospecting Research Group, School of Engineering, Universidad de La Sabana, Chía, Colombia
- Bioorganic Chemistry Laboratory, Universidad Militar Nueva Granada, Cajicá, Colombia
| | - Luisa Villamil
- Doctoral Program in Biosciences, School of Engineering, Universidad de La Sabana, Chía, Colombia
| | - Luis Díaz
- Bioprospecting Research Group, School of Engineering, Universidad de La Sabana, Chía, Colombia
| | - Ericsson Coy-Barrera
- Bioorganic Chemistry Laboratory, Universidad Militar Nueva Granada, Cajicá, Colombia
| |
Collapse
|
5
|
Dynamic symbioses reveal pathways to coral survival through prolonged heatwaves. Nat Commun 2020; 11:6097. [PMID: 33293528 PMCID: PMC7723047 DOI: 10.1038/s41467-020-19169-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 09/17/2020] [Indexed: 11/08/2022] Open
Abstract
Prospects for coral persistence through increasingly frequent and extended heatwaves seem bleak. Coral recovery from bleaching is only known to occur after temperatures return to normal, and mitigation of local stressors does not appear to augment coral survival. Capitalizing on a natural experiment in the equatorial Pacific, we track individual coral colonies at sites spanning a gradient of local anthropogenic disturbance through a tropical heatwave of unprecedented duration. Unexpectedly, some corals survived the event by recovering from bleaching while still at elevated temperatures. These corals initially had heat-sensitive algal symbiont communities, endured bleaching, and then recovered through proliferation of heat-tolerant symbionts. This pathway to survival only occurred in the absence of strong local stressors. In contrast, corals in highly disturbed areas were already dominated by heat-tolerant symbionts, and despite initially resisting bleaching, these corals had no survival advantage in one species and 3.3 times lower survival in the other. These unanticipated connections between disturbance, coral symbioses and heat stress resilience reveal multiple pathways to coral survival through future prolonged heatwaves.
Collapse
|
6
|
Newkirk CR, Frazer TK, Martindale MQ, Schnitzler CE. Adaptation to Bleaching: Are Thermotolerant Symbiodiniaceae Strains More Successful Than Other Strains Under Elevated Temperatures in a Model Symbiotic Cnidarian? Front Microbiol 2020; 11:822. [PMID: 32431680 PMCID: PMC7214872 DOI: 10.3389/fmicb.2020.00822] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 04/06/2020] [Indexed: 01/01/2023] Open
Abstract
The ability of some symbiotic cnidarians to resist and better withstand stress factors that cause bleaching is a trait that is receiving increased attention. The adaptive bleaching hypothesis postulates that cnidarians that can form a stable symbiosis with thermotolerant Symbiodiniaceae strains may cope better with increasing seawater temperatures. We used polyps of the scyphozoan, Cassiopea xamachana, as a model system to test symbiosis success under heat stress. We sought to determine: (1) if aposymbiotic C. xamachana polyps could establish and maintain a symbiosis with both native and non-native strains of Symbiodiniaceae that all exhibit different tolerances to heat, (2) whether polyps with these newly acquired Symbiodiniaceae strains would strobilate (produce ephyra), and (3) if thermally tolerant Symbiodiniaceae strains that established and maintained a symbiosis exhibited greater success in response to heat stress (even if they are not naturally occurring in Cassiopea). Following recolonization of aposymbiotic C. xamachana polyps with different strains, we found that: (1) strains Smic, Stri, Slin, and Spil all established a stable symbiosis that promoted strobilation and (2) strains Bmin1 and Bmin2 did not establish a stable symbiosis and strobilation did not occur. Strains Smic, Stri, Slin, and Spil were used in a subsequent bleaching experiment; each of the strains was introduced to a subset of aposymbiotic polyps and once polyp tissues were saturated with symbionts they were subjected to elevated temperatures - 32°C and 34°C - for 2 weeks. Our findings indicate that, in general, pairings of polyps with Symbiodiniaceae strains that are native to Cassiopea (Stri and Smic) performed better than a non-native strain (Slin) even though this strain has a high thermotolerance. This suggests a degree of partner specificity that may limit the adaptive potential of certain cnidarians to increased ocean warming. We also observed that the free-living, non-native thermotolerant strain Spil was relatively successful in resisting bleaching during experimental trials. This suggests that free-living Symbiodiniaceae may provide a supply of potentially "new" thermotolerant strains to cnidarians following a bleaching event.
Collapse
Affiliation(s)
- Casandra R. Newkirk
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, United States
- Fisheries and Aquatic Sciences Program, School of Forest Resources and Conservation, University of Florida, Gainesville, FL, United States
| | - Thomas K. Frazer
- Fisheries and Aquatic Sciences Program, School of Forest Resources and Conservation, University of Florida, Gainesville, FL, United States
- School of Natural Resources and Environment, University of Florida, Gainesville, FL, United States
| | - Mark Q. Martindale
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, United States
| | - Christine E. Schnitzler
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, United States
| |
Collapse
|
7
|
Transgenerational inheritance of shuffled symbiont communities in the coral Montipora digitata. Sci Rep 2019; 9:13328. [PMID: 31527788 PMCID: PMC6746730 DOI: 10.1038/s41598-019-50045-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 09/05/2019] [Indexed: 11/08/2022] Open
Abstract
Adult organisms may "prime" their offspring for environmental change through a number of genetic and non-genetic mechanisms, termed parental effects. Some coral species may shuffle the proportions of Symbiodiniaceae within their endosymbiotic communities, subsequently altering their thermal tolerance, but it is unclear if shuffled communities are transferred to offspring. We evaluated Symbiodiniaceae community composition in tagged colonies of Montipora digitata over two successive annual spawning seasons and the 2016 bleaching event on the Great Barrier Reef. ITS2 amplicon sequencing was applied to four families (four maternal colonies and 10-12 eggs per family) previously sampled and sequenced the year before to characterize shuffling potential in these M. digitata colonies and determine if shuffled abundances were preserved in gametes. Symbiont densities and photochemical efficiencies differed significantly among adults in 2016, suggesting differential responses to increased temperatures. Low-abundance ("background") sequence variants differed more among years than between maternal colonies and offspring. Results indicate that shuffling can occur in a canonically 'stable' symbiosis, and that the shuffled community is heritable. Hence, acclimatory changes like shuffling of the Symbiodiniaceae community are not limited to the lifetime of an adult coral and that shuffled communities are inherited across generations in a species with vertical symbiont transmission. Although previously hypothesized, to our knowledge, this is the first evidence that shuffled Symbiodiniaceae communities (at both the inter- and intra- genera level) can be inherited by offspring and supports the hypothesis that shuffling in microbial communities may serve as a mechanism of rapid coral acclimation to changing environmental conditions.
Collapse
|
8
|
van Oppen MJH, Bongaerts P, Frade P, Peplow L, Boyd SE, Nim HT, Bay LK. Adaptation to reef habitats through selection on the coral animal and its associated microbiome. Mol Ecol 2018; 27:2956-2971. [DOI: 10.1111/mec.14763] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 06/01/2018] [Accepted: 06/04/2018] [Indexed: 01/02/2023]
Affiliation(s)
- Madeleine J. H. van Oppen
- Australian Institute of Marine Science; Townsville MC Qld Australia
- School of BioSciences; University of Melbourne; Parkville Vic. Australia
| | - Pim Bongaerts
- Global Change Institute; The University of Queensland; St Lucia Qld Australia
- California Academy of Sciences; San Francisco California
| | - Pedro Frade
- Centre of Marine Sciences (CCMAR); University of Algarve; Faro Portugal
| | - Lesa M. Peplow
- Australian Institute of Marine Science; Townsville MC Qld Australia
| | - Sarah E. Boyd
- Faculty of Information Technology; Monash University; Melbourne Vic. Australia
| | - Hieu T. Nim
- Faculty of Information Technology; Monash University; Melbourne Vic. Australia
- Australian Regenerative Medicine Institute; Monash University; Melbourne Vic. Australia
| | - Line K. Bay
- Australian Institute of Marine Science; Townsville MC Qld Australia
| |
Collapse
|
9
|
Neal BP, Khen A, Treibitz T, Beijbom O, O'Connor G, Coffroth MA, Knowlton N, Kriegman D, Mitchell BG, Kline DI. Caribbean massive corals not recovering from repeated thermal stress events during 2005-2013. Ecol Evol 2017; 7:1339-1353. [PMID: 28261447 PMCID: PMC5330915 DOI: 10.1002/ece3.2706] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/03/2016] [Accepted: 11/27/2016] [Indexed: 11/17/2022] Open
Abstract
Massive coral bleaching events associated with high sea surface temperatures are forecast to become more frequent and severe in the future due to climate change. Monitoring colony recovery from bleaching disturbances over multiyear time frames is important for improving predictions of future coral community changes. However, there are currently few multiyear studies describing long‐term outcomes for coral colonies following acute bleaching events. We recorded colony pigmentation and size for bleached and unbleached groups of co‐located conspecifics of three major reef‐building scleractinian corals (Orbicella franksi, Siderastrea siderea, and Stephanocoenia michelini; n = 198 total) in Bocas del Toro, Panama, during the major 2005 bleaching event and then monitored pigmentation status and changes live tissue colony size for 8 years (2005–2013). Corals that were bleached in 2005 demonstrated markedly different response trajectories compared to unbleached colony groups, with extensive live tissue loss for bleached corals of all species following bleaching, with mean live tissue losses per colony 9 months postbleaching of 26.2% (±5.4 SE) for O. franksi, 35.7% (±4.7 SE) for S. michelini, and 11.2% (±3.9 SE) for S. siderea. Two species, O. franksi and S. michelini, later recovered to net positive growth, which continued until a second thermal stress event in 2010. Following this event, all species again lost tissue, with previously unbleached colony species groups experiencing greater declines than conspecific sample groups, which were previously bleached, indicating a possible positive acclimative response. However, despite this beneficial effect for previously bleached corals, all groups experienced substantial net tissue loss between 2005 and 2013, indicating that many important Caribbean reef‐building corals will likely suffer continued tissue loss and may be unable to maintain current benthic coverage when faced with future thermal stress forecast for the region, even with potential benefits from bleaching‐related acclimation.
Collapse
Affiliation(s)
| | - Adi Khen
- The Scripps Institution for Oceanography University of California San Diego La Jolla CA USA
| | - Tali Treibitz
- Marine Imaging Lab Leon H. Charney School of Marine Sciences University of Haifa Haifa Israel
| | - Oscar Beijbom
- Berkeley Vision and Learning Center Electrical Engineering and Computer Sciences University of California Berkeley Berkeley CA USA
| | - Grace O'Connor
- Environmental Studies Department Colby College Waterville ME USA
| | - Mary Alice Coffroth
- Department of Geology State University of New York at Buffalo Buffalo NY USA
| | - Nancy Knowlton
- National Museum of Natural History Smithsonian Institution Washington DC USA
| | - David Kriegman
- Computer Science and Engineering University of California, San Diego La Jolla CA USA
| | - B Greg Mitchell
- The Scripps Institution for Oceanography University of California San Diego La Jolla CA USA
| | - David I Kline
- The Scripps Institution for Oceanography University of California San Diego La Jolla CA USA; Smithsonian Tropical Research Institute Ancon Republic of Panama
| |
Collapse
|
10
|
Diversity, Distribution and Stability of Symbiodinium in Reef Corals of the Eastern Tropical Pacific. CORAL REEFS OF THE EASTERN TROPICAL PACIFIC 2017. [DOI: 10.1007/978-94-017-7499-4_13] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
11
|
Hawkins TD, Warner ME. Warm preconditioning protects against acute heat-induced respiratory dysfunction and delays bleaching in a symbiotic sea anemone. ACTA ACUST UNITED AC 2016; 220:969-983. [PMID: 27980125 DOI: 10.1242/jeb.150391] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 12/08/2016] [Indexed: 12/18/2022]
Abstract
Preconditioning to non-stressful warming can protect some symbiotic cnidarians against the high temperature-induced collapse of their mutualistic endosymbiosis with photosynthetic dinoflagellates (Symbiodinium spp.), a process known as bleaching. Here, we sought to determine whether such preconditioning is underpinned by differential regulation of aerobic respiration. We quantified in vivo metabolism and mitochondrial respiratory enzyme activity in the naturally symbiotic sea anemone Exaiptasia pallida preconditioned to 30°C for >7 weeks as well as anemones kept at 26°C. Preconditioning resulted in increased Symbiodinium photosynthetic activity and holobiont (host+symbiont) respiration rates. Biomass-normalised activities of host respiratory enzymes [citrate synthase and the mitochondrial electron transport chain (mETC) complexes I and IV] were higher in preconditioned animals, suggesting that increased holobiont respiration may have been due to host mitochondrial biogenesis and/or enlargement. Subsequent acute heating of preconditioned and 'thermally naive' animals to 33°C induced dramatic increases in host mETC complex I and Symbiodinium mETC complex II activities only in thermally naive E. pallida These changes were not reflected in the activities of other respiratory enzymes. Furthermore, bleaching in preconditioned E. pallida (defined as the significant loss of symbionts) was delayed by several days relative to the thermally naive group. These findings suggest that changes to mitochondrial biogenesis and/or function in symbiotic cnidarians during warm preconditioning might play a protective role during periods of exposure to stressful heating.
Collapse
Affiliation(s)
- Thomas D Hawkins
- School of Marine Science and Policy, College of Earth, Ocean and Environment, University of Delaware, 700 Pilottown Road, Lewes, DE 19958, USA
| | - Mark E Warner
- School of Marine Science and Policy, College of Earth, Ocean and Environment, University of Delaware, 700 Pilottown Road, Lewes, DE 19958, USA
| |
Collapse
|
12
|
McIlroy SE, Gillette P, Cunning R, Klueter A, Capo T, Baker AC, Coffroth MA. The effects of Symbiodinium (Pyrrhophyta) identity on growth, survivorship, and thermal tolerance of newly settled coral recruits. JOURNAL OF PHYCOLOGY 2016; 52:1114-1124. [PMID: 27690269 DOI: 10.1111/jpy.12471] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 08/23/2016] [Indexed: 05/23/2023]
Abstract
For many coral species, the obligate association with phylogenetically diverse algal endosymbiont species is dynamic in time and space. Here, we used controlled laboratory inoculations of newly settled, aposymbiotic corals (Orbicella faveolata) with two cultured species of algal symbiont (Symbiodinium microadriaticum and S. minutum) to examine the role of symbiont identity on growth, survivorship, and thermal tolerance of the coral holobiont. We evaluated these data in the context of Symbiodinium photophysiology for 9 months post-settlement and also during a 5-d period of elevated temperatures Our data show that recruits that were inoculated with S. minutum grew significantly slower than those inoculated with S. microadriaticum (occasionally co-occurring with S. minutum), but that there was no difference in survivorship of O. faveolata polyps infected with Symbiodinium. However, photophysiological metrics (∆Fv/F'm, the efficiency with which available light is used to drive photosynthesis and α, the maximum light utilization coefficient) were higher in those slower growing recruits containing S. minutum. These findings suggest that light use (i.e., photophysiology) and carbon acquisition by the coral host (i.e., host growth) are decoupled, but did not distinguish the source of this difference. Neither Symbiodinium treatment demonstrated a significant negative effect of a 5-d exposure to temperatures as high as 32°C under low light conditions similar to those measured at settlement habitats.
Collapse
Affiliation(s)
- Shelby E McIlroy
- Graduate Program in Evolution, Ecology, and Behavior, University at Buffalo, 126 Cooke Hall, Buffalo, New York, 14260, USA
| | - Phillip Gillette
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Csy, Miami, Florida, 33149, USA
| | - Ross Cunning
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Csy, Miami, Florida, 33149, USA
| | - Anke Klueter
- Department of Geology, University at Buffalo, 126 Cooke Hall, Buffalo, New York, 14260, USA
| | - Tom Capo
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Csy, Miami, Florida, 33149, USA
| | - Andrew C Baker
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Csy, Miami, Florida, 33149, USA
| | - Mary Alice Coffroth
- Graduate Program in Evolution, Ecology, and Behavior, University at Buffalo, 126 Cooke Hall, Buffalo, New York, 14260, USA
| |
Collapse
|
13
|
|
14
|
Blackall LL, Wilson B, van Oppen MJH. Coral-the world's most diverse symbiotic ecosystem. Mol Ecol 2015; 24:5330-47. [DOI: 10.1111/mec.13400] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Revised: 09/21/2015] [Accepted: 09/24/2015] [Indexed: 12/22/2022]
Affiliation(s)
- Linda L. Blackall
- Department of Chemistry and Biotechnology; Faculty of Science, Engineering & Technology; Swinburne University of Technology; Melbourne Vic. 3122 Australia
| | - Bryan Wilson
- Marine Microbiology Research Group; Department of Biology; University of Bergen; Thormøhlensgate 53B 5020 Bergen Norway
| | - Madeleine J. H. van Oppen
- Australian Institute of Marine Science; PMB No. 3 Townsville MC Qld. 4810 Australia
- School of BioSciences; The University of Melbourne; Parkville Vic. 3010 Australia
| |
Collapse
|
15
|
Abstract
The genetic enhancement of wild animals and plants for characteristics that benefit human populations has been practiced for thousands of years, resulting in impressive improvements in commercially valuable species. Despite these benefits, genetic manipulations are rarely considered for noncommercial purposes, such as conservation and restoration initiatives. Over the last century, humans have driven global climate change through industrialization and the release of increasing amounts of CO2, resulting in shifts in ocean temperature, ocean chemistry, and sea level, as well as increasing frequency of storms, all of which can profoundly impact marine ecosystems. Coral reefs are highly diverse ecosystems that have suffered massive declines in health and abundance as a result of these and other direct anthropogenic disturbances. There is great concern that the high rates, magnitudes, and complexity of environmental change are overwhelming the intrinsic capacity of corals to adapt and survive. Although it is important to address the root causes of changing climate, it is also prudent to explore the potential to augment the capacity of reef organisms to tolerate stress and to facilitate recovery after disturbances. Here, we review the risks and benefits of the improvement of natural and commercial stocks in noncoral reef systems and advocate a series of experiments to determine the feasibility of developing coral stocks with enhanced stress tolerance through the acceleration of naturally occurring processes, an approach known as (human)-assisted evolution, while at the same time initiating a public dialogue on the risks and benefits of this approach.
Collapse
|
16
|
Work T, Meteyer C. To understand coral disease, look at coral cells. ECOHEALTH 2014; 11:610-8. [PMID: 24723160 DOI: 10.1007/s10393-014-0931-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 03/23/2014] [Accepted: 03/24/2014] [Indexed: 05/15/2023]
Abstract
Diseases threaten corals globally, but 40 years on their causes remain mostly unknown. We hypothesize that inconsistent application of a complete diagnostic approach to coral disease has contributed to this slow progress. We quantified methods used to investigate coral disease in 492 papers published between 1965 and 2013. Field surveys were used in 65% of the papers, followed by biodetection (43%), laboratory trials (20%), microscopic pathology (21%), and field trials (9%). Of the microscopic pathology efforts, 57% involved standard histopathology at the light microscopic level (12% of the total investigations), with the remainder dedicated to electron or fluorescence microscopy. Most (74%) biodetection efforts focused on culture or molecular characterization of bacteria or fungi from corals. Molecular and immunological tools have been used to incriminate infectious agents (mainly bacteria) as the cause of coral diseases without relating the agent to specific changes in cell and tissue pathology. Of 19 papers that declared an infectious agent as a cause of disease in corals, only one (5%) used microscopic pathology, and none fulfilled all of the criteria required to satisfy Koch's postulates as applied to animal diseases currently. Vertebrate diseases of skin and mucosal surfaces present challenges similar to corals when trying to identify a pathogen from a vast array of environmental microbes, and diagnostic approaches regularly used in these cases might provide a model for investigating coral diseases. We hope this review will encourage specialists of disease in domestic animals, wildlife, fish, shellfish, and humans to contribute to the emerging field of coral disease.
Collapse
Affiliation(s)
- Thierry Work
- Honolulu Field Station, National Wildlife Health Center, US Geological Survey, PO Box 50167, Honolulu, HI, 96850, USA,
| | | |
Collapse
|
17
|
Williamson DH, Ceccarelli DM, Evans RD, Jones GP, Russ GR. Habitat dynamics, marine reserve status, and the decline and recovery of coral reef fish communities. Ecol Evol 2014; 4:337-54. [PMID: 24634720 PMCID: PMC3936382 DOI: 10.1002/ece3.934] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 11/26/2013] [Accepted: 11/29/2013] [Indexed: 11/08/2022] Open
Abstract
Severe climatic disturbance events often have major impacts on coral reef communities, generating cycles of decline and recovery, and in some extreme cases, community-level phase shifts from coral-to algal-dominated states. Benthic habitat changes directly affect reef fish communities, with low coral cover usually associated with low fish diversity and abundance. No-take marine reserves (NTRs) are widely advocated for conserving biodiversity and enhancing the sustainability of exploited fish populations. Numerous studies have documented positive ecological and socio-economic benefits of NTRs; however, the ability of NTRs to ameliorate the effects of acute disturbances on coral reefs has seldom been investigated. Here, we test these factors by tracking the dynamics of benthic and fish communities, including the important fishery species, coral trout (Plectropomus spp.), over 8 years in both NTRs and fished areas in the Keppel Island group, Great Barrier Reef, Australia. Two major disturbances impacted the reefs during the monitoring period, a coral bleaching event in 2006 and a freshwater flood plume in 2011. Both disturbances generated significant declines in coral cover and habitat complexity, with subsequent declines in fish abundance and diversity, and pronounced shifts in fish assemblage structure. Coral trout density also declined in response to the loss of live coral, however, the approximately 2:1 density ratio between NTRs and fished zones was maintained over time. The only post-disturbance refuges for coral trout spawning stocks were within the NTRs that escaped the worst effects of the disturbances. Although NTRs had little discernible effect on the temporal dynamics of benthic or fish communities, it was evident that the post-disturbance refuges for coral trout spawning stocks within some NTRs may be critically important to regional-scale population persistence and recovery.
Collapse
Affiliation(s)
- David H Williamson
- ARC Centre of Excellence for Coral Reef Studies, James Cook University Townsville, Queensland, 4811, Australia
| | - Daniela M Ceccarelli
- ARC Centre of Excellence for Coral Reef Studies, James Cook University Townsville, Queensland, 4811, Australia
| | - Richard D Evans
- Department of Parks & Wildlife 17 Dick Perry Ave., Kensington, Perth, Western Australia, 6151, Australia ; Oceans Institute, School of Plant Biology, University of Western Australia Crawley, Western Australia, 6009, Australia
| | - Geoffrey P Jones
- ARC Centre of Excellence for Coral Reef Studies, James Cook University Townsville, Queensland, 4811, Australia ; School of Marine and Tropical Biology, James Cook University Townsville, Queensland, 4811, Australia
| | - Garry R Russ
- ARC Centre of Excellence for Coral Reef Studies, James Cook University Townsville, Queensland, 4811, Australia ; School of Marine and Tropical Biology, James Cook University Townsville, Queensland, 4811, Australia
| |
Collapse
|
18
|
Dimond JL, Bingham BL, le Muller-Parker G, Oakley CA. Symbiont physiology and population dynamics before and during symbiont shifts in a flexible algal-cnidarian symbiosis. JOURNAL OF PHYCOLOGY 2013; 49:1074-1083. [PMID: 27007628 DOI: 10.1111/jpy.12112] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 08/05/2013] [Indexed: 06/05/2023]
Abstract
For cnidarians that can undergo shifts in algal symbiont relative abundance, the underlying algal physiological changes that accompany these shifts are not well known. The sea anemone Anthopleura elegantissima associates with the dinoflagellate Symbiodinium muscatinei and the chlorophyte Elliptochloris marina, symbionts with very different tolerances to light and temperature. We compared the performance of these symbionts in anemones maintained in an 8-11.5 month outdoor common garden experiment with simulated intertidal conditions and three levels of shading (2, 43, and 85% ambient irradiance). Symbiont densities, mitotic indices, photophysiology and pigments were assessed at three time points during the summer, a period of high irradiance and solar heating during aerial exposure. Whereas S. muscatinei was either neutrally or positively affected by higher irradiance treatments, E. marina responded mostly negatively to high irradiance. E. marina in the 85% irradiance treatment exhibited significantly reduced Pmax and chlorophyll early in the summer, but it was not until nearly 3 months later that a shift in symbiont relative abundance toward S. muscatinei occurred, coincident with bleaching. Symbiont densities and proportions remained largely stable in all other treatments over time, and displacement of S. muscatinei by E. marina was not observed in the 2% irradiance treatment despite the potentially better performance of E. marina. While our results support the view that rapid changes in symbiont relative abundance are typically associated with symbiont physiological dysfunction and bleaching, they also show that significant temporal lags may occur between the onset of symbiont stress and shifts in symbiont relative abundances.
Collapse
Affiliation(s)
- James L Dimond
- Shannon Point Marine Center, Western Washington University, 1900 Shannon Point Rd., Anacortes, Washington, 98221, USA
| | - Brian L Bingham
- Department of Environmental Sciences, Western Washington University, 516 High St., Bellingham, Washington, 98225, USA
| | - Gisè le Muller-Parker
- Division of Graduate Education, National Science Foundation, Arlington, Virginia, 22230, USA
| | - Clinton A Oakley
- Department of Plant Biology, University of Georgia, Athens, Georgia, 30602, USA
| |
Collapse
|
19
|
Penin L, Vidal-Dupiol J, Adjeroud M. Response of coral assemblages to thermal stress: are bleaching intensity and spatial patterns consistent between events? ENVIRONMENTAL MONITORING AND ASSESSMENT 2013; 185:5031-5042. [PMID: 23054287 DOI: 10.1007/s10661-012-2923-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 09/27/2012] [Indexed: 06/01/2023]
Abstract
Mass bleaching events resulting in coral mortality are among the greatest threats to coral reefs, and are projected to increase in frequency and intensity with global warming. Achieving a better understanding of the consistency of the response of coral assemblages to thermal stress, both spatially and temporally, is essential to determine which reefs are more able to tolerate climate change. We compared variations in spatial and taxonomic patterns between two bleaching events at the scale of an island (Moorea Island, French Polynesia). Despite similar thermal stress and light conditions, bleaching intensity was significantly lower in 2007 (approximately 37 % of colonies showed signs of bleaching) than in 2002, when 55 % of the colonies bleached. Variations in the spatial patterns of bleaching intensity were consistent between the two events. Among nine sampling stations at three locations and three depths, the stations at which the bleaching response was lowest in 2002 were those that showed the lowest levels of bleaching in 2007. The taxonomic patterns of susceptibility to bleaching were also consistent between the two events. These findings have important implications for conservation because they indicate that corals are capable of acclimatization and/or adaptation and that, even at small spatial scales, some areas are consistently more susceptible to bleaching than others.
Collapse
Affiliation(s)
- Lucie Penin
- Laboratoire ECOMAR, Faculté des Sciences, Université de La Réunion, BP 7151, 97715 Saint-Denis Cedex 09, Reunion Island, France.
| | | | | |
Collapse
|
20
|
Fabricius KE, Cséke S, Humphrey C, De'ath G. Does trophic status enhance or reduce the thermal tolerance of scleractinian corals? A review, experiment and conceptual framework. PLoS One 2013; 8:e54399. [PMID: 23349876 PMCID: PMC3547885 DOI: 10.1371/journal.pone.0054399] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 12/11/2012] [Indexed: 11/19/2022] Open
Abstract
Global warming, and nutrient and sediment runoff from coastal development, both exert increasing pressures on coastal coral reefs. The objective of this study was to resolve the question of whether coastal eutrophication may protect corals from thermal stress by improving their nutritional status, or rather diminish their thermal tolerance through the synergy of dual stressors. A review of previous studies on the topic of combined trophic status and heat exposure on the thermal tolerance of corals reveals a broad range of outcomes, including synergistic, additive and antagonistic effects. We conducted a 90-day long experiment exposing corals to realistic levels of elevated nutrients and sediments, and heat stress. Colonies of two common scleractinian corals (Acropora millepora and Montipora tuberculosa) were kept in coastal seawater, or coastal seawater that was further organically and nutrient enriched (OE), and/or enriched with nitrate. Batches of OE were created daily, facilitating nutrient uptake, plankton succession and organic enrichment as observed in coastal waters. After 10 days of acclimation, 67% of the colonies had their temperature gradually increased from 27° to 31.2°C. After 3-7 weeks of heat stress, colonies of both species had significantly greater reductions in fluorescence yields and lower survival in OE than without addition of OE. Furthermore, photophysiological recovery was incomplete 31-38 days after ending the heat stress only in the OE treatments. Nitrate alone had no measurable effect on survival, bleaching and recovery in either species. Skeletal growth rates were reduced by 45% in heat-stressed A. millepora and by 24% in OE-exposed M. tuberculosa. We propose a conceptual trophic framework that resolves some of the apparently contradictory outcomes revealed by the review. Our study shows that management actions to reduce coastal eutrophication can improve the resistance and resilience of vulnerable coastal coral reefs to warming temperatures.
Collapse
|
21
|
Dimond JL, Holzman BJ, Bingham BL. Thicker host tissues moderate light stress in a cnidarian endosymbiont. J Exp Biol 2012; 215:2247-54. [DOI: 10.1242/jeb.067991] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
The susceptibility of algal–cnidarian holobionts to environmental stress is dependent on attributes of both host and symbiont, but the role of the host is often unclear. We examined the influence of the host on symbiont light stress, comparing the photophysiology of the chlorophyte symbiont Elliptochloris marina in two species of sea anemones in the genus Anthopleura. After 3 months of acclimation in outdoor tanks, polyp photoprotective contraction behavior was similar between the two host species, but photochemical efficiency was 1.5 times higher in A. xanthogrammica than in A. elegantissima. Maximum relative electron transport rates, derived from rapid light curves, were 1.5 times higher in A. xanthogrammica than in A. elegantissima when symbionts were inside intact tissues, but were not significantly different between host species upon removal of outer (epidermis and mesoglea) tissue layers from symbiont-containing gastrodermal cells. Tissues of A. xanthogrammica were 1.8 times thicker than those of A. elegantissima, with outer tissue layers attenuating 1.6 times more light. We found no significant differences in light absorption properties per unit volume of tissue, confirming the direct effect of tissue thickness on light attenuation. The thicker tissues of A. xanthogrammica thus provide a favorable environment for E. marina – a relatively stress-susceptible symbiont – and may explain its higher prevalence and expanded range in A. xanthogrammica along the Pacific coast of North America. Our findings also support a photoprotective role for thicker host tissues in reef corals that has long been thought to influence variability in bleaching susceptibility among coral taxa.
Collapse
Affiliation(s)
- James L. Dimond
- Shannon Point Marine Center, Western Washington University, Anacortes, WA, USA
| | | | - Brian L. Bingham
- Department of Environmental Sciences, Western Washington University, Bellingham, WA, USA
| |
Collapse
|
22
|
Cooper TF, Ulstrup KE, Dandan SS, Heyward AJ, Kühl M, Muirhead A, O'Leary RA, Ziersen BEF, Van Oppen MJH. Niche specialization of reef-building corals in the mesophotic zone: metabolic trade-offs between divergent Symbiodinium types. Proc Biol Sci 2011; 278:1840-50. [PMID: 21106586 PMCID: PMC3097838 DOI: 10.1098/rspb.2010.2321] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Accepted: 11/01/2010] [Indexed: 11/12/2022] Open
Abstract
The photobiology of two reef corals and the distribution of associated symbiont types were investigated over a depth gradient of 0-60 m at Scott Reef, Western Australia. Pachyseris speciosa hosted mainly the same Symbiodinium C type similar to C3 irrespective of sampling depth. By contrast, Seriatopora hystrix hosted predominantly Symbiodinium type D1a or D1a-like at shallow depths while those in deeper water were dominated by a Symbiodinium C type closely related to C1. The photosynthesis/respiration (P/R) ratio increased consistently with depth at the two sampling times (November 2008 and April 2009) for P. speciosa and in November 2008 only for S. hystrix, suggesting a reduction in metabolic energy expended for every unit of energy obtained from photosynthesis. However, in April 2009, shallow colonies of S. hystrix exhibited decreased P/R ratios down to depths of approximately 23 m, below which the ratio increased towards the maximum depth sampled. This pattern was mirrored by changes in tissue biomass determined as total protein content. The depth of change in the direction of the P/R ratio correlated with a shift from Symbiodinium D to C-dominated colonies. We conclude that while photobiological flexibility is vital for persistence in contrasting light regimes, a shift in Symbiodinium type may also confer a functional advantage albeit at a metabolic cost with increased depth.
Collapse
Affiliation(s)
- Timothy F Cooper
- Australian Institute of Marine Science, UWA Oceans Institute (M096), 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Nunes F, Norris RD, Knowlton N. Implications of isolation and low genetic diversity in peripheral populations of an amphi-Atlantic coral. Mol Ecol 2009; 18:4283-97. [PMID: 19765228 DOI: 10.1111/j.1365-294x.2009.04347.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- F Nunes
- Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive MC 0208, La Jolla, CA 92093-0208, USA.
| | | | | |
Collapse
|