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Coffroth MA, Buccella LA, Eaton KM, Lasker HR, Gooding AT, Franklin H. What makes a winner? Symbiont and host dynamics determine Caribbean octocoral resilience to bleaching. SCIENCE ADVANCES 2023; 9:eadj6788. [PMID: 37992160 PMCID: PMC10664981 DOI: 10.1126/sciadv.adj6788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/23/2023] [Indexed: 11/24/2023]
Abstract
Unlike reef-building, scleractinian corals, Caribbean soft corals (octocorals) have not suffered marked declines in abundance associated with anthropogenic ocean warming. Both octocorals and reef-building scleractinians depend on a nutritional symbiosis with single-celled algae living within their tissues. In both groups, increased ocean temperatures can induce symbiont loss (bleaching) and coral death. Multiple heat waves from 2014 to 2016 resulted in widespread damage to reef ecosystems and provided an opportunity to examine the bleaching response of three Caribbean octocoral species. Symbiont densities declined during the heat waves but recovered quickly, and colony mortality was low. The dominant symbiont genotypes within a host generally did not change, and all colonies hosted symbiont species in the genus Breviolum. Their association with thermally tolerant symbionts likely contributes to the octocoral holobiont's resistance to mortality and the resilience of their symbiont populations. The resistance and resilience of Caribbean octocorals offer clues for the future of coral reefs.
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Affiliation(s)
| | - Louis A. Buccella
- Graduate Program in Evolution, Ecology and Behavior, University at Buffalo, Buffalo NY 14260, USA
| | - Katherine M. Eaton
- Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA
| | - Howard R. Lasker
- Department of Geology, University at Buffalo, Buffalo, NY 14260, USA
| | - Alyssa T. Gooding
- Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA
| | - Harleena Franklin
- Department of Geology, University at Buffalo, Buffalo, NY 14260, USA
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2
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McQuagge A, Pahl KB, Wong S, Melman T, Linn L, Lowry S, Hoadley KD. Cellular traits regulate fluorescence-based light-response phenotypes of coral photosymbionts living in-hospite. Front Physiol 2023; 14:1244060. [PMID: 37885802 PMCID: PMC10598705 DOI: 10.3389/fphys.2023.1244060] [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: 06/21/2023] [Accepted: 09/21/2023] [Indexed: 10/28/2023] Open
Abstract
Diversity across algal family Symbiodiniaceae contributes to the environmental resilience of certain coral species. Chlorophyll-a fluorescence measurements are frequently used to determine symbiont health and resilience, but more work is needed to refine these tools and establish how they relate to underlying cellular traits. We examined trait diversity in symbionts from the generas Cladocopium and Durusdinium, collected from 12 aquacultured coral species. Photophysiological metrics (ΦPSII, σPSII, ρ, τ1, τ2, antenna bed quenching, non-photochemical quenching, and qP) were assessed using a prototype multi-spectral fluorometer over a variable light protocol which yielded a total of 1,360 individual metrics. Photophysiological metrics were then used to establish four unique light-response phenotypic variants. Corals harboring C15 were predominantly found within a single light-response phenotype which clustered separately from all other coral fragments. The majority of Durusdinium dominated colonies also formed a separate light-response phenotype which it shared with a few C1 dominated corals. C15 and D1 symbionts appear to differ in which mechanisms they use to dissipate excess light energy. Spectrally dependent variability is also observed across light-response phenotypes that may relate to differences in photopigment utilization. Symbiont cell biochemical and structural traits (atomic C:N:P, cell size, chlorophyll-a, neutral lipid content) was also assessed within each sample and differ across light-response phenotypes, linking photophysiological metrics with underlying primary cellular traits. Strong correlations between first- and second-order traits, such as Quantum Yield and cellular N:P content, or light dissipation pathways (qP and NPQ) and C:P underline differences across symbiont types and may also provide a means for using fluorescence-based metrics as biomarkers for certain primary-cellular traits.
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Affiliation(s)
- Audrey McQuagge
- Department of Biology, University of Alabama, Tuscaloosa, AL, United States
- Dauphin Island Sea Lab, Dauphin Island, AL, United States
| | - K. Blue Pahl
- Department of Biology, University of Alabama, Tuscaloosa, AL, United States
- Dauphin Island Sea Lab, Dauphin Island, AL, United States
| | - Sophie Wong
- Dauphin Island Sea Lab, Dauphin Island, AL, United States
- Department of Environmental Science, University of Virginia, Charlottesville, VA, United States
| | - Todd Melman
- Reef Systems Coral Farm, New Albany, OH, United States
| | - Laura Linn
- Dauphin Island Sea Lab, Dauphin Island, AL, United States
| | - Sean Lowry
- Department of Biology, University of Alabama, Tuscaloosa, AL, United States
- Dauphin Island Sea Lab, Dauphin Island, AL, United States
| | - Kenneth D. Hoadley
- Department of Biology, University of Alabama, Tuscaloosa, AL, United States
- Dauphin Island Sea Lab, Dauphin Island, AL, United States
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3
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Butler CC, Turnham KE, Lewis AM, Nitschke MR, Warner ME, Kemp DW, Hoegh-Guldberg O, Fitt WK, van Oppen MJH, LaJeunesse TC. Formal recognition of host-generalist species of dinoflagellate (Cladocopium, Symbiodiniaceae) mutualistic with Indo-Pacific reef corals. JOURNAL OF PHYCOLOGY 2023; 59:698-711. [PMID: 37126002 DOI: 10.1111/jpy.13340] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 03/30/2023] [Accepted: 03/30/2023] [Indexed: 06/01/2023]
Abstract
The existence of widespread species with the capacity to endure diverse, or variable, environments are of importance to ecological and genetic research, and conservation. Such "ecological generalists" are more likely to have key adaptations that allow them to better tolerate the physiological challenges of rapid climate change. Reef-building corals are dependent on endosymbiotic dinoflagellates (Family: Symbiodiniaceae) for their survival and growth. While these symbionts are biologically diverse, certain genetic types appear to have broad geographic distributions and are mutualistic with various host species from multiple genera and families in the order Scleractinia that must acquire their symbionts through horizontal transmission. Despite the considerable ecological importance of putative host-generalist symbionts, they lack formal species descriptions. In this study, we used molecular, ecological, and morphological evidence to verify the existence of five new host-generalist species in the symbiodiniacean genus Cladocopium. Their geographic distribution and prevalence among host communities corresponds to prevailing environmental conditions at both regional and local scales. The influence that each species has on host physiology may partially explain regional differences in thermal sensitivities among coral communities. The potential increased prevalence of a generalist species that endures environmental instability is a consequential ecological response to warming oceans. Large-scale shifts in symbiont dominance could ensure reef coral persistence and productivity in the near term. Ultimately, these formal designations should advance scientific communication and generate informed research questions on the physiology and ecology of coral-dinoflagellate mutualisms.
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Affiliation(s)
- Caleb C Butler
- Penn State University, University Park, Pennsylvania, USA
| | - Kira E Turnham
- Penn State University, University Park, Pennsylvania, USA
| | - Allison M Lewis
- Penn State University, University Park, Pennsylvania, USA
- Lawrence Berkeley National Laboratory, Berkely, California, USA
| | - Matthew R Nitschke
- Australian Institute of Marine Science, Townsville, Queensland, Australia
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | | | | | | | | | - Madeleine J H van Oppen
- Australian Institute of Marine Science, Townsville, Queensland, Australia
- School of BioSciences, University of Melbourne, Parkville, Victoria, Australia
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Davies SW, Gamache MH, Howe-Kerr LI, Kriefall NG, Baker AC, Banaszak AT, Bay LK, Bellantuono AJ, Bhattacharya D, Chan CX, Claar DC, Coffroth MA, Cunning R, Davy SK, del Campo J, Díaz-Almeyda EM, Frommlet JC, Fuess LE, González-Pech RA, Goulet TL, Hoadley KD, Howells EJ, Hume BCC, Kemp DW, Kenkel CD, Kitchen SA, LaJeunesse TC, Lin S, McIlroy SE, McMinds R, Nitschke MR, Oakley CA, Peixoto RS, Prada C, Putnam HM, Quigley K, Reich HG, Reimer JD, Rodriguez-Lanetty M, Rosales SM, Saad OS, Sampayo EM, Santos SR, Shoguchi E, Smith EG, Stat M, Stephens TG, Strader ME, Suggett DJ, Swain TD, Tran C, Traylor-Knowles N, Voolstra CR, Warner ME, Weis VM, Wright RM, Xiang T, Yamashita H, Ziegler M, Correa AMS, Parkinson JE. Building consensus around the assessment and interpretation of Symbiodiniaceae diversity. PeerJ 2023; 11:e15023. [PMID: 37151292 PMCID: PMC10162043 DOI: 10.7717/peerj.15023] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 02/17/2023] [Indexed: 05/09/2023] Open
Abstract
Within microeukaryotes, genetic variation and functional variation sometimes accumulate more quickly than morphological differences. To understand the evolutionary history and ecology of such lineages, it is key to examine diversity at multiple levels of organization. In the dinoflagellate family Symbiodiniaceae, which can form endosymbioses with cnidarians (e.g., corals, octocorals, sea anemones, jellyfish), other marine invertebrates (e.g., sponges, molluscs, flatworms), and protists (e.g., foraminifera), molecular data have been used extensively over the past three decades to describe phenotypes and to make evolutionary and ecological inferences. Despite advances in Symbiodiniaceae genomics, a lack of consensus among researchers with respect to interpreting genetic data has slowed progress in the field and acted as a barrier to reconciling observations. Here, we identify key challenges regarding the assessment and interpretation of Symbiodiniaceae genetic diversity across three levels: species, populations, and communities. We summarize areas of agreement and highlight techniques and approaches that are broadly accepted. In areas where debate remains, we identify unresolved issues and discuss technologies and approaches that can help to fill knowledge gaps related to genetic and phenotypic diversity. We also discuss ways to stimulate progress, in particular by fostering a more inclusive and collaborative research community. We hope that this perspective will inspire and accelerate coral reef science by serving as a resource to those designing experiments, publishing research, and applying for funding related to Symbiodiniaceae and their symbiotic partnerships.
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Affiliation(s)
- Sarah W. Davies
- Department of Biology, Boston University, Boston, MA, United States
| | - Matthew H. Gamache
- Department of Integrative Biology, University of South Florida, Tampa, FL, United States
| | | | | | - Andrew C. Baker
- Rosenstiel School of Marine, Atmospheric, and Earth Science, University of Miami, Miami, FL, United States
| | - Anastazia T. Banaszak
- Unidad Académica de Sistemas Arrecifales, Universidad Nacional Autónoma de México, Puerto Morelos, Mexico
| | - Line Kolind Bay
- Australian Institute of Marine Science, Townsville, Australia
| | - Anthony J. Bellantuono
- Department of Biological Sciences, Florida International University, Miami, FL, United States
| | - Debashish Bhattacharya
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, United States
| | - Cheong Xin Chan
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Danielle C. Claar
- Nearshore Habitat Program, Washington State Department of Natural Resources, Olympia, WA, USA
| | | | - Ross Cunning
- Daniel P. Haerther Center for Conservation and Research, John G. Shedd Aquarium, Chicago, IL, United States
| | - Simon K. Davy
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Javier del Campo
- Institut de Biologia Evolutiva (CSIC - Universitat Pompeu Fabra), Barcelona, Catalonia, Spain
| | | | - Jörg C. Frommlet
- Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Campus Universitário de Santiago, Aveiro, Portugal
| | - Lauren E. Fuess
- Department of Biology, Texas State University, San Marcos, TX, United States
| | - Raúl A. González-Pech
- Department of Integrative Biology, University of South Florida, Tampa, FL, United States
- Department of Biology, Pennsylvania State University, State College, PA, United States
| | - Tamar L. Goulet
- Department of Biology, University of Mississippi, University, MS, United States
| | - Kenneth D. Hoadley
- Department of Biological Sciences, University of Alabama—Tuscaloosa, Tuscaloosa, AL, United States
| | - Emily J. Howells
- National Marine Science Centre, Faculty of Science and Engineering, Southern Cross University, Coffs Harbour, NSW, Australia
| | | | - Dustin W. Kemp
- Department of Biology, University of Alabama—Birmingham, Birmingham, Al, United States
| | - Carly D. Kenkel
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
| | - Sheila A. Kitchen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Todd C. LaJeunesse
- Department of Biology, Pennsylvania State University, University Park, PA, United States
| | - Senjie Lin
- Department of Marine Sciences, University of Connecticut, Mansfield, CT, United States
| | - Shelby E. McIlroy
- Swire Institute of Marine Science, School of Biological Sciences, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Ryan McMinds
- Center for Global Health and Infectious Disease Research, University of South Florida, Tampa, FL, United States
| | | | - Clinton A. Oakley
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Raquel S. Peixoto
- Red Sea Research Center (RSRC), Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Carlos Prada
- Department of Biological Sciences, University of Rhode Island, Kingston, RI, United States
| | - Hollie M. Putnam
- Department of Biological Sciences, University of Rhode Island, Kingston, RI, United States
| | | | - Hannah G. Reich
- Department of Biological Sciences, University of Rhode Island, Kingston, RI, United States
| | - James Davis Reimer
- Department of Biology, Chemistry and Marine Sciences, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa, Japan
| | | | - Stephanie M. Rosales
- The Cooperative Institute For Marine and Atmospheric Studies, Miami, FL, United States
| | - Osama S. Saad
- Department of Biological Oceanography, Red Sea University, Port-Sudan, Sudan
| | - Eugenia M. Sampayo
- School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Scott R. Santos
- Department of Biological Sciences, University at Buffalo, Buffalo, NY, United States
| | - Eiichi Shoguchi
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Edward G. Smith
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Michael Stat
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW, Australia
| | - Timothy G. Stephens
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, United States
| | - Marie E. Strader
- Department of Biology, Texas A&M University, College Station, TX, United States
| | - David J. Suggett
- Red Sea Research Center (RSRC), Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, Australia
| | - Timothy D. Swain
- Department of Marine and Environmental Science, Nova Southeastern University, Dania Beach, FL, United States
| | - Cawa Tran
- Department of Biology, University of San Diego, San Diego, CA, United States
| | - Nikki Traylor-Knowles
- Rosenstiel School of Marine, Atmospheric, and Earth Science, University of Miami, Miami, FL, United States
| | | | - Mark E. Warner
- School of Marine Science and Policy, University of Delaware, Lewes, DE, United States
| | - Virginia M. Weis
- Department of Integrative Biology, Oregon State University, Corvallis, OR, United States
| | - Rachel M. Wright
- Department of Biological Sciences, Southern Methodist University, Dallas, TX, United States
| | - Tingting Xiang
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Hiroshi Yamashita
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, Ishigaki, Okinawa, Japan
| | - Maren Ziegler
- Department of Animal Ecology & Systematics, Justus Liebig University Giessen (Germany), Giessen, Germany
| | | | - John Everett Parkinson
- Department of Integrative Biology, University of South Florida, Tampa, FL, United States
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5
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Johnston EC, Cunning R, Burgess SC. Cophylogeny and specificity between cryptic coral species (Pocillopora spp.) at Mo'orea and their symbionts (Symbiodiniaceae). Mol Ecol 2022; 31:5368-5385. [PMID: 35960256 PMCID: PMC9805206 DOI: 10.1111/mec.16654] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 06/30/2022] [Accepted: 08/08/2022] [Indexed: 01/09/2023]
Abstract
The congruence between phylogenies of tightly associated groups of organisms (cophylogeny) reflects evolutionary links between ecologically important interactions. However, despite being a classic example of an obligate symbiosis, tests of cophylogeny between scleractinian corals and their photosynthetic algal symbionts have been hampered in the past because both corals and algae contain genetically unresolved and morphologically cryptic species. Here, we studied co-occurring, cryptic Pocillopora species from Mo'orea, French Polynesia, that differ in their relative abundance across depth. We constructed new phylogenies of the host Pocillopora (using complete mitochondrial genomes, genomic loci, and thousands of single nucleotide polymorphisms) and their Symbiodiniaceae symbionts (using ITS2 and psbAncr markers) and tested for cophylogeny. The analysis supported the presence of five Pocillopora species on the fore reef at Mo'orea that mostly hosted either Cladocopium latusorum or C. pacificum. Only Pocillopora species hosting C. latusorum also hosted taxa from Symbiodinium and Durusdinium. In general, the Cladocopium phylogeny mirrored the Pocillopora phylogeny. Within Cladocopium species, lineages also differed in their associations with Pocillopora haplotypes, except those showing evidence of nuclear introgression, and with depth in the two most common Pocillopora species. We also found evidence for a new Pocillopora species (haplotype 10), that has so far only been sampled from French Polynesia, that warrants formal identification. The linked phylogenies of these Pocillopora and Cladocopium species and lineages suggest that symbiont speciation is driven by niche diversification in the host, but there is still evidence for symbiont flexibility in some cases.
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Affiliation(s)
- Erika C. Johnston
- Department of Biological ScienceFlorida State UniversityTallahasseeFloridaUSA
| | - Ross Cunning
- Daniel P. Haerther Center for Conservation and ResearchJohn G. Shedd AquariumChicagoIllinoisUSA
| | - Scott C. Burgess
- Department of Biological ScienceFlorida State UniversityTallahasseeFloridaUSA
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6
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Endosymbiotic Symbiodinium clades occurrence and influence on coral growth and resilience during stress. Symbiosis 2022. [DOI: 10.1007/s13199-022-00846-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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7
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LaJeunesse TC, Wiedenmann J, Casado-Amezúa P, D’Ambra I, Turnham KE, Nitschke MR, Oakley CA, Goffredo S, Spano CA, Cubillos VM, Davy SK, Suggett DJ. Revival of Philozoon Geddes for host-specialized dinoflagellates, ‘zooxanthellae’, in animals from coastal temperate zones of northern and southern hemispheres. EUROPEAN JOURNAL OF PHYCOLOGY 2022. [PMID: 0 DOI: 10.1080/09670262.2021.1914863] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Affiliation(s)
- Todd C. LaJeunesse
- Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Joerg Wiedenmann
- Coral Reef Laboratory, University of Southampton, Southampton, UK
| | - Pilar Casado-Amezúa
- Hombre y Territorio Association (HyT), Alameda Santa Eufemia 24. 41940, Tomares, Sevilla, Spain
| | - Isabella D’Ambra
- Integrative Marine Ecology Department, Stazione Zoologica Anton Dohrn, Napoli, Italy
| | - Kira E. Turnham
- Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Matthew R. Nitschke
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2007, Australia
- School of Biological Sciences, Victoria University of Wellington, Wellington 6140, New Zealand
| | - Clinton A. Oakley
- School of Biological Sciences, Victoria University of Wellington, Wellington 6140, New Zealand
| | - Stefano Goffredo
- Marine Science Group, Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
- Fano Marine Center, The Inter-Institute Center for Research on Marine Biodiversity, Resources and Biotechnologies, Fano, Italy
| | | | - Victor M. Cubillos
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
- Laboratorio Costero de Recursos Acuáticos de Calfuco, Universidad Austral de Chile, Valdivia, Chile
| | - Simon K. Davy
- School of Biological Sciences, Victoria University of Wellington, Wellington 6140, New Zealand
| | - David J. Suggett
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2007, Australia
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Cryoprotectant treatment tests on three morphologically diverse marine dinoflagellates and the cryopreservation of Breviolum sp. (Symbiodiniaceae). Sci Rep 2022; 12:646. [PMID: 35027556 PMCID: PMC8758677 DOI: 10.1038/s41598-021-04227-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 12/17/2021] [Indexed: 11/08/2022] Open
Abstract
Dinoflagellates are among the most diverse group of microalgae. Many dinoflagellate species have been isolated and cultured, and these are used for scientific, industrial, pharmaceutical, and agricultural applications. Maintaining cultures is time-consuming, expensive, and there is a risk of contamination or genetic drift. Cryopreservation offers an efficient means for their long-term preservation. Cryopreservation of larger dinoflagellate species is challenging and to date there has been only limited success. In this study, we explored the effect of cryoprotectant agents (CPAs) and freezing methods on three species: Vulcanodinium rugosum, Alexandrium pacificum and Breviolum sp. A total of 12 CPAs were assessed at concentrations between 5 and 15%, as well as in combination with dimethyl sulfoxide (DMSO) and other non-penetrating CPAs. Two freezing techniques were employed: rapid freezing and controlled-rate freezing. Breviolum sp. was successfully cryopreserved using 15% DMSO. Despite exploring different CPAs and optimizing the freezing techniques, we were unable to successfully cryopreserve V. rugosum and A. pacificum. For Breviolum sp. there was higher cell viability (45.4 ± 2.2%) when using the controlled-rate freezing compared to the rapid freezing technique (10.0 ± 2.8%). This optimized cryopreservation protocol will be of benefit for the cryopreservation of other species from the family Symbiodiniaceae.
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Turnham KE, Wham DC, Sampayo E, LaJeunesse TC. Mutualistic microalgae co-diversify with reef corals that acquire symbionts during egg development. THE ISME JOURNAL 2021; 15:3271-3285. [PMID: 34012104 PMCID: PMC8528872 DOI: 10.1038/s41396-021-01007-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 04/23/2021] [Accepted: 05/04/2021] [Indexed: 02/04/2023]
Abstract
The application of molecular genetics has reinvigorated and improved how species are defined and investigated scientifically, especially for morphologically cryptic micro-organisms. Here we show how species recognition improves understanding of the ecology and evolution of mutualisms between reef-building corals and their mutualistic dinoflagellates (i.e. Symbiodiniaceae). A combination of genetic, ecological, and morphological evidence defines two sibling species of Cladocopium (formerly Symbiodinium Clade C), specific only to host corals in the common genus Pocillopora, which transmit their obligate symbionts during oogenesis. Cladocopium latusorum sp. nov. is symbiotic with P. grandis/meandrina while the smaller-celled C. pacificum sp. nov. associates with P. verrucosa. Both symbiont species form mutualisms with Pocillopora that brood their young. Populations of each species, like their hosts, are genetically well connected across the tropical and subtropical Pacific Ocean, indicating a capacity for long-range dispersal. A molecular clock approximates their speciation during the late Pliocene or early Pleistocene as Earth underwent cycles of precipitous cooling and warming; and corresponds to when their hosts were also diversifying. The long temporal and spatial maintenance of high host fidelity, as well as genetic connectivity across thousands of kilometers, indicates that distinct ecological attributes and close evolutionary histories will restrain the adaptive responses of corals and their specialized symbionts to rapid climate warming.
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Affiliation(s)
| | - Drew C Wham
- Penn State University, University Park, PA, USA
| | | | - Todd C LaJeunesse
- Penn State University, University Park, PA, USA.
- Penn State Institutes of Energy and the Environment, University Park, PA, USA.
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10
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Hoadley KD, Pettay DT, Lewis A, Wham D, Grasso C, Smith R, Kemp DW, LaJeunesse T, Warner ME. Different functional traits among closely related algal symbionts dictate stress endurance for vital Indo-Pacific reef-building corals. GLOBAL CHANGE BIOLOGY 2021; 27:5295-5309. [PMID: 34255912 PMCID: PMC9291761 DOI: 10.1111/gcb.15799] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 05/24/2023]
Abstract
Reef-building corals in the genus Porites are one of the most important constituents of Indo-Pacific reefs. Many species within this genus tolerate abnormally warm water and exhibit high specificity for particular kinds of endosymbiotic dinoflagellates that cope with thermal stress better than those living in other corals. Still, during extreme ocean heating, some Porites exhibit differences in their stress tolerance. While corals have different physiological qualities, it remains unknown whether the stability and performance of these mutualisms is influenced by the physiology and genetic relatedness of their symbionts. We investigated two ubiquitous Pacific reef corals, Porites rus and Porites cylindrica, from warmer inshore and cooler offshore reef systems in Palau. While these corals harbored a similar kind of symbiont in the genus Cladocopium (within the ITS2 C15 subclade), rapidly evolving genetic markers revealed evolutionarily diverged lineages corresponding to each Porites species living in each reef habitat. Furthermore, these closely related Cladocopium lineages were differentiated by their densities in host tissues, cell volume, chlorophyll concentration, gross photosynthesis, and photoprotective pathways. When assessed using several physiological proxies, these previously undifferentiated symbionts contrasted in their tolerance to thermal stress. Symbionts within P. cylindrica were relatively unaffected by exposure to 32℃ for 14 days, whereas P. rus colonies lost substantial numbers of photochemically compromised symbionts. Heating reduced the ability of the offshore symbiont associated with P. rus to translocate carbon to the coral. By contrast, high temperatures enhanced symbiont carbon assimilation and delivery to the coral skeleton of inshore P. cylindrica. This study indicates that large physiological differences exist even among closely related symbionts, with significant implications for thermal susceptibility among reef-building Porites.
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Affiliation(s)
- Kenneth D. Hoadley
- School of Marine Science and PolicyUniversity of DelawareLewesUK
- Biological SciencesUniversity of AlabamaTuscaloosaAlabamaUSA
- Dauphin Island Sea LabDauphin IslandAlabamaUSA
| | - Daniel. T. Pettay
- School of Marine Science and PolicyUniversity of DelawareLewesUK
- Present address:
University of South CarolinaBeaufortSouth CarolinaUSA
| | - Allison Lewis
- Department of BiologyPennsylvania State Institutes of Energy and the EnvironmentUniversity ParkPennsylvaniaUSA
- Present address:
National Science FoundationSilver SpringsMarylandUSA
| | - Drew Wham
- Department of BiologyPennsylvania State Institutes of Energy and the EnvironmentUniversity ParkPennsylvaniaUSA
| | - Chris Grasso
- School of Marine Science and PolicyUniversity of DelawareLewesUK
| | - Robin Smith
- Science Under SailWellington ParkQLDAustralia
- Present address:
The Nature ConservancySt. CroixUS Virgin IslandsUSA
| | - Dustin W. Kemp
- Department of BiologyUniversity of AlabamaBirminghamAlabamaUSA
| | - Todd LaJeunesse
- Department of BiologyPennsylvania State Institutes of Energy and the EnvironmentUniversity ParkPennsylvaniaUSA
| | - Mark E. Warner
- School of Marine Science and PolicyUniversity of DelawareLewesUK
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11
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Reich HG, Kitchen SA, Stankiewicz KH, Devlin-Durante M, Fogarty ND, Baums IB. Genomic variation of an endosymbiotic dinoflagellate (Symbiodinium 'fitti') among closely related coral hosts. Mol Ecol 2021; 30:3500-3514. [PMID: 33964051 DOI: 10.1111/mec.15952] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 05/01/2021] [Accepted: 05/04/2021] [Indexed: 12/20/2022]
Abstract
Mutualisms where hosts are coupled metabolically to their symbionts often exhibit high partner fidelity. Most reef-building coral species form obligate symbioses with a specific species of photosymbionts, dinoflagellates in the family Symbiodiniaceae, despite needing to acquire symbionts early in their development from environmental sources. Three Caribbean acroporids (Acropora palmata, A. cervicornis and their F1 hybrid) are sympatric across much of their range, but often occupy different depth and light habitats. Throughout this range, both species and their hybrid associate with the endosymbiotic dinoflagellate Symbiodinium 'fitti'. Because light (and therefore depth) influences the physiology of dinoflagellates, we investigated whether S. 'fitti' populations from each host taxon were differentiated genetically. Single nucleotide polymorphisms (SNPs) among S. 'fitti' strains were identified by aligning shallow metagenomic sequences of acroporid colonies sampled from across the Caribbean to a ~600-Mb draft assembly of the S. 'fitti' genome (from the CFL14120 A. cervicornis metagenome). Phylogenomic and multivariate analyses revealed that genomic variation among S. 'fitti' strains partitioned to each host taxon rather than by biogeographical origin. This is particularly noteworthy because the hybrid has a sparse fossil record and may be of relatively recent origin. A subset (37.6%) of the SNPs putatively under selection were nonsynonymous mutations predicted to alter protein efficiency. Differences in genomic variation of S. 'fitti' strains from each host taxon may reflect the unique selection pressures created by the microenvironments associated with each host. The nonrandom sorting among S. 'fitti' strains to different hosts could be the basis for lineage diversification via disruptive selection, leading to ecological specialization and ultimately speciation.
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Affiliation(s)
- Hannah G Reich
- Department of Biology, The Pennsylvania State University, University Park, PA, USA
| | - Sheila A Kitchen
- Department of Biology, The Pennsylvania State University, University Park, PA, USA
| | | | | | - Nicole D Fogarty
- Department of Biology and Marine Biology, Center for Marine Science, University of North Carolina Wilmington, Wilmington, NC, USA
| | - Iliana B Baums
- Department of Biology, The Pennsylvania State University, University Park, PA, USA
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12
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Pochon X, LaJeunesse TC. Miliolidium n. gen, a New Symbiodiniacean Genus Whose Members Associate with Soritid Foraminifera or Are Free-Living. J Eukaryot Microbiol 2021; 68:e12856. [PMID: 33966311 DOI: 10.1111/jeu.12856] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 05/03/2021] [Accepted: 05/03/2021] [Indexed: 01/02/2023]
Abstract
The dinoflagellate family Symbiodiniaceae comprises numerous divergent genera containing species whose ecologies range from endosymbiotic to free-living. While many associate with invertebrates including corals, sea anemones, jellyfish, giant clams, and flatworms, others occur within the cytoplasm of large protists, most notably benthic foraminifera in the sub-family Soritinae. Recent systematic revisions to the Symbiodiniaceae left out formal naming of some divergent lineages because each lacked a representative type species to erect new genus names. Here we provide genetic, morphological and ecological evidence to describe a new genus and species. Miliolidium n. gen. is closely related to the genus Durusdinium and contains several genetically divergent ecologically distinct lineages found in distant geographic locations indicating an Indo-Pacific wide distribution. One of these, Miliolidium leei n. sp., is represented by an isolate cultured from Amphisorus sp. originally collected in the Gulf of Eilat, northern Red Sea. Its peripheral chloroplast extensions are uniquely petal- or lobe-shaped, and cells possess a pyrenoid with three stalks connecting to chloroplasts, and without thylakoid intrusions. It is related to an isolate cultured from an azooxanthellate sponge from Palau and another that is commonly harbored by the soritid Marginopora vertebralis in shallow reef habitats from Guam. Research on Symbiodiniaceae diversity including free-living species in benthic habitats and those mutualistic with soritid foraminifera remains extremely limited as does our knowledge of their diversity, physiology, biogeography, and ecology.
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Affiliation(s)
- Xavier Pochon
- Coastal and Freshwater Group, Cawthron Institute, Private Bag 2, Nelson, 7042, New Zealand
- Institute of Marine Science, University of Auckland, Pri vate Bag 349, Warkworth, 0941, New Zealand
| | - Todd C LaJeunesse
- Penn State University, University Park, Pennsylvania, 16802, USA
- Penn State Institutes of Energy and the Environment, University Park, Pennsylvania, 16802, USA
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13
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A Phylogeny-Informed Analysis of the Global Coral-Symbiodiniaceae Interaction Network Reveals that Traits Correlated with Thermal Bleaching Are Specific to Symbiont Transmission Mode. mSystems 2021; 6:6/3/e00266-21. [PMID: 33947806 PMCID: PMC8269218 DOI: 10.1128/msystems.00266-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The complex network of associations between corals and their dinoflagellates (family Symbiodiniaceae) are the basis of coral reef ecosystems but are sensitive to increasing global temperatures. Coral-symbiont interactions are restricted by ecological and evolutionary determinants that constrain partner choice and influence holobiont response to environmental stress; however, little is known about how these processes shape thermal resilience of the holobiont. Here, we built a network of global coral-Symbiodiniaceae associations, mapped species traits (e.g., symbiont transmission mode and biogeography) and phylogenetic relationships of both partners onto the network, and assigned thermotolerance to both host and symbiont nodes. Using network analysis and phylogenetic comparative methods, we determined the contribution of species traits to thermal resilience of the holobiont, while accounting for evolutionary patterns among species. We found that the network shows nonrandom interactions among species, which are shaped by evolutionary history, symbiont transmission mode (horizontally transmitted [HT] or vertically transmitted [VT] corals) and biogeography. Coral phylogeny, but not Symbiodiniaceae phylogeny, symbiont transmission mode, or biogeography, was a good predictor of thermal resilience. Closely related corals have similar Symbiodiniaceae interaction patterns and bleaching susceptibilities. Nevertheless, the association patterns that explain increased host thermal resilience are not generalizable across the entire network but are instead unique to HT and VT corals. Under nonstress conditions, thermally resilient VT coral species associate with thermotolerant phylotypes and limit their number of unique symbionts and overall symbiont thermotolerance diversity, while thermally resilient HT coral species associate with a few host-specific symbiont phylotypes. IMPORTANCE Recent advances have revealed a complex network of interactions between coral and Symbiodiniaceae. Specifically, nonrandom association patterns, which are determined in part by restrictions imposed by symbiont transmission mode, increase the sensitivity of the overall network to thermal stress. However, little is known about the extent to which coral-Symbiodiniaceae network resistance to thermal stress is shaped by host and symbiont species phylogenetic relationships and host and symbiont species traits, such as symbiont transmission mode. We built a frequency-weighted global coral-Symbiodiniaceae network and used network analysis and phylogenetic comparative methods to show that evolutionary relatedness, but not transmission mode, predicts thermal resilience of the coral-Symbiodiniaceae holobiont. Consequently, thermal stress events could result in nonrandom pruning of susceptible lineages and loss of taxonomic diversity with catastrophic effects on community resilience to future events. Our results show that inclusion of the contribution of evolutionary and ecological processes will further our understanding of the fate of coral assemblages under climate change.
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14
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Rossbach S, Hume BCC, Cárdenas A, Perna G, Voolstra CR, Duarte CM. Flexibility in Red Sea Tridacna maxima-Symbiodiniaceae associations supports environmental niche adaptation. Ecol Evol 2021; 11:3393-3406. [PMID: 33841792 PMCID: PMC8019035 DOI: 10.1002/ece3.7299] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 01/13/2021] [Accepted: 02/02/2021] [Indexed: 12/20/2022] Open
Abstract
Giant clams (Tridacninae) are important members of Indo-Pacific coral reefs and among the few bivalve groups that live in symbiosis with unicellular algae (Symbiodiniaceae). Despite the importance of these endosymbiotic dinoflagellates for clam ecology, the diversity and specificity of these associations remain relatively poorly studied, especially in the Red Sea. Here, we used the internal transcribed spacer 2 (ITS2) rDNA gene region to investigate Symbiodiniaceae communities associated with Red Sea Tridacna maxima clams. We sampled five sites spanning 1,300 km (10° of latitude, from the Gulf of Aqaba, 29°N, to the Farasan Banks, 18°N) along the Red Sea's North-South environmental gradient. We detected a diverse and structured assembly of host-associated algae with communities demonstrating region and site-specificity. Specimens from the Gulf of Aqaba harbored three genera of Symbiodiniaceae, Cladocopium, Durusdinium, and Symbiodinium, while at all other sites clams associated exclusively with algae from the Symbiodinium genus. Of these exclusively Symbiodinium-associating sites, the more northern (27° and 22°) and more southern sites (20° and 18°) formed two separate groupings despite site-specific algal genotypes being resolved at each site. These groupings were congruent with the genetic break seen across multiple marine taxa in the Red Sea at approximately 19°, and along with our documented site-specificity of algal communities, contrasted the panmictic distribution of the T. maxima host. As such, our findings indicate flexibility in T. maxima-Symbiodiniaceae associations that may explain its relatively high environmental plasticity and offers a mechanism for environmental niche adaptation.
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Affiliation(s)
- Susann Rossbach
- Biological and Environmental Science and Engineering DivisionRed Sea Research Center (RSRC) and Computational Bioscience Research Center (CBRC)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Benjamin C. C. Hume
- Biological and Environmental Science and Engineering DivisionRed Sea Research Center (RSRC)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
- Department of BiologyUniversity of KonstanzKonstanzGermany
| | - Anny Cárdenas
- Department of BiologyUniversity of KonstanzKonstanzGermany
| | - Gabriela Perna
- Department of BiologyUniversity of KonstanzKonstanzGermany
| | - Christian R. Voolstra
- Biological and Environmental Science and Engineering DivisionRed Sea Research Center (RSRC)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
- Department of BiologyUniversity of KonstanzKonstanzGermany
| | - Carlos M. Duarte
- Biological and Environmental Science and Engineering DivisionRed Sea Research Center (RSRC) and Computational Bioscience Research Center (CBRC)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
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15
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Davies SW, Moreland KN, Wham DC, Kanke MR, Matz MV. Cladocopium community divergence in two Acropora coral hosts across multiple spatial scales. Mol Ecol 2020; 29:4559-4572. [PMID: 33002237 DOI: 10.1111/mec.15668] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 09/14/2020] [Accepted: 09/18/2020] [Indexed: 12/11/2022]
Abstract
Many broadly-dispersing corals acquire their algal symbionts (Symbiodiniaceae) "horizontally" from their environment upon recruitment. Horizontal transmission could promote coral fitness across diverse environments provided that corals can associate with divergent algae across their range and that these symbionts exhibit reduced dispersal potential. Here we quantified community divergence of Cladocopium algal symbionts in two coral host species (Acropora hyacinthus, Acropora digitifera) across two spatial scales (reefs on the same island, and between islands) across the Micronesian archipelago using microsatellites. We find that both hosts associated with a variety of multilocus genotypes (MLG) within two genetically distinct Cladocopium lineages (C40, C21), confirming that Acropora coral hosts associate with a range of Cladocopium symbionts across this region. Both C40 and C21 included multiple asexual lineages bearing identical MLGs, many of which spanned host species, reef sites within islands, and even different islands. Both C40 and C21 exhibited moderate host specialization and divergence across islands. In addition, within every island, algal symbiont communities were significantly clustered by both host species and reef site, highlighting that coral-associated Cladocopium communities are structured across small spatial scales and within hosts on the same reef. This is in stark contrast to their coral hosts, which never exhibited significant genetic divergence between reefs on the same island. These results support the view that horizontal transmission could improve local fitness for broadly dispersing Acropora coral species.
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Affiliation(s)
- Sarah W Davies
- Department of Biology, Boston University, Boston, MA, USA.,Department of Integrative Biology, The University of Texas at Austin, Austin, TX, USA
| | - Kelsey N Moreland
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX, USA
| | - Drew C Wham
- Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Matt R Kanke
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Mikhail V Matz
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX, USA
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16
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van Oppen MJH, Medina M. Coral evolutionary responses to microbial symbioses. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190591. [PMID: 32772672 PMCID: PMC7435167 DOI: 10.1098/rstb.2019.0591] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2020] [Indexed: 12/19/2022] Open
Abstract
This review explores how microbial symbioses may have influenced and continue to influence the evolution of reef-building corals (Cnidaria; Scleractinia). The coral holobiont comprises a diverse microbiome including dinoflagellate algae (Dinophyceae; Symbiodiniaceae), bacteria, archaea, fungi and viruses, but here we focus on the Symbiodiniaceae as knowledge of the impact of other microbial symbionts on coral evolution is scant. Symbiosis with Symbiodiniaceae has extended the coral's metabolic capacity through metabolic handoffs and horizontal gene transfer (HGT) and has contributed to the ecological success of these iconic organisms. It necessitated the prior existence or the evolution of a series of adaptations of the host to attract and select the right symbionts, to provide them with a suitable environment and to remove disfunctional symbionts. Signatures of microbial symbiosis in the coral genome include HGT from Symbiodiniaceae and bacteria, gene family expansions, and a broad repertoire of oxidative stress response and innate immunity genes. Symbiosis with Symbiodiniaceae has permitted corals to occupy oligotrophic waters as the algae provide most corals with the majority of their nutrition. However, the coral-Symbiodiniaceae symbiosis is sensitive to climate warming, which disrupts this intimate relationship, causing coral bleaching, mortality and a worldwide decline of coral reefs. This article is part of the theme issue 'The role of the microbiome in host evolution'.
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Affiliation(s)
- Madeleine J. H. van Oppen
- School of BioSciences, The University of Melbourne, Parkville, 3010 Victoria, Australia
- Australian Institute of Marine Science, PMB No. 3, Townsville MC, 4810 Queensland, Australia
| | - Mónica Medina
- Department of Biology, The Pennsylvania State University, 208 Mueller Lab, University Park, PA 16802, USA
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17
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Endosymbiont diversity and community structure in Porites lutea from Southeast Asia are driven by a suite of environmental variables. Symbiosis 2020. [DOI: 10.1007/s13199-020-00671-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
AbstractMany corals depend upon the highly specialised and intricate relationship they form with Symbiodiniaceae algal symbionts. Porites lutea is a massive reef-building coral found throughout Southeast Asia that hosts these endosymbionts obligately. Yet despite the prevalence and importance of P. lutea as one of the most dominant corals here, its associated Symbiodiniaceae communities have not been precisely characterised. In this study, we used high-throughput DNA amplicon sequencing of the nuclear internal transcribed spacer 2 (ITS2) to characterise the diversity, community structure and biogeographic distribution of Symbiodiniaceae in P. lutea throughout Singapore and Peninsular Malaysia. Consistent with previous studies, we found that Cladocopium was the most dominant genus among all samples, and Cladocopium C15 was the most dominant type (or subclade) with 100% occurrence in all samples from every study site. Results also revealed numerous Symbiodiniaceae types associated with P. lutea that were previously undetected in Southeast Asia. Endosymbiont diversity and community variation are driven by a combination of site-specific mean monthly cloud cover and variance in monthly sea surface temperature. This study contributes baseline data toward understanding differences in Symbiodiniaceae assemblages hosted by P. lutea, shedding light on how they might be indicative of particular environmental conditions and coral responses.
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18
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Vohsen SA, Anderson KE, Gade AM, Gruber-Vodicka HR, Dannenberg RP, Osman EO, Dubilier N, Fisher CR, Baums IB. Deep-sea corals provide new insight into the ecology, evolution, and the role of plastids in widespread apicomplexan symbionts of anthozoans. MICROBIOME 2020; 8:34. [PMID: 32164774 PMCID: PMC7068898 DOI: 10.1186/s40168-020-00798-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 02/05/2020] [Indexed: 05/09/2023]
Abstract
BACKGROUND Apicomplexans are the causative agents of major human diseases such as malaria and toxoplasmosis. A novel group of apicomplexans, recently named corallicolids, have been detected in corals inhabiting tropical shallow reefs. These apicomplexans may represent a transitional lifestyle between free-living phototrophs and obligate parasites. To shed light on the evolutionary history of apicomplexans and to investigate their ecology in association with corals, we screened scleractinians, antipatharians, alcyonaceans, and zoantharians from shallow, mesophotic, and deep-sea communities. We detected corallicolid plastids using 16S metabarcoding, sequenced the nuclear 18S rRNA gene of corallicolids from selected samples, assembled and annotated the plastid and mitochondrial genomes from a corallicolid that associates with a deep-sea coral, and screened the metagenomes of four coral species for corallicolids. RESULTS We detected 23 corallicolid plastotypes that were associated with 14 coral species from three orders and depths down to 1400 m. Individual plastotypes were restricted to coral hosts within a single depth zone and within a single taxonomic order of corals. Some clusters of closely related corallicolids were revealed that associated with closely related coral species. However, the presence of divergent corallicolid lineages that associated with similar coral species and depths suggests that corallicolid/coral relations are flexible over evolutionary timescales and that a large diversity of apicomplexans may remain undiscovered. The corallicolid plastid genome from a deep-sea coral contained four genes involved in chlorophyll biosynthesis: the three genes of the LIPOR complex and acsF. CONCLUSIONS The presence of corallicolid apicomplexans in corals below the photic zone demonstrates that they are not restricted to shallow-water reefs and are more general anthozoan symbionts. The presence of LIPOR genes in the deep-sea corallicolid precludes a role involving photosynthesis and suggests they may be involved in a different function. Thus, these genes may represent another set of genetic tools whose function was adapted from photosynthesis as the ancestors of apicomplexans evolved towards parasitic lifestyles. Video abstract.
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Affiliation(s)
- Samuel A Vohsen
- Biology Department, Pennsylvania State University, University Park, PA, USA.
| | - Kaitlin E Anderson
- Biology Department, Pennsylvania State University, University Park, PA, USA
| | - Andrea M Gade
- Biology Department, Pennsylvania State University, University Park, PA, USA
| | | | - Richard P Dannenberg
- Biology Department, Pennsylvania State University, University Park, PA, USA
- Epic, Madison, WI, USA
| | - Eslam O Osman
- Biology Department, Pennsylvania State University, University Park, PA, USA
- Marine Biology Department, Faculty of Science, Al Azhar University, Cairo, Egypt
| | - Nicole Dubilier
- Department of Symbiosis, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Charles R Fisher
- Biology Department, Pennsylvania State University, University Park, PA, USA
| | - Iliana B Baums
- Biology Department, Pennsylvania State University, University Park, PA, USA
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19
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Baums IB, Baker AC, Davies SW, Grottoli AG, Kenkel CD, Kitchen SA, Kuffner IB, LaJeunesse TC, Matz MV, Miller MW, Parkinson JE, Shantz AA. Considerations for maximizing the adaptive potential of restored coral populations in the western Atlantic. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2019; 29:e01978. [PMID: 31332879 PMCID: PMC6916196 DOI: 10.1002/eap.1978] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/13/2019] [Accepted: 06/21/2019] [Indexed: 05/06/2023]
Abstract
Active coral restoration typically involves two interventions: crossing gametes to facilitate sexual larval propagation; and fragmenting, growing, and outplanting adult colonies to enhance asexual propagation. From an evolutionary perspective, the goal of these efforts is to establish self-sustaining, sexually reproducing coral populations that have sufficient genetic and phenotypic variation to adapt to changing environments. Here, we provide concrete guidelines to help restoration practitioners meet this goal for most Caribbean species of interest. To enable the persistence of coral populations exposed to severe selection pressure from many stressors, a mixed provenance strategy is suggested: genetically unique colonies (genets) should be sourced both locally as well as from more distant, environmentally distinct sites. Sourcing three to four genets per reef along environmental gradients should be sufficient to capture a majority of intraspecies genetic diversity. It is best for practitioners to propagate genets with one or more phenotypic traits that are predicted to be valuable in the future, such as low partial mortality, high wound healing rate, high skeletal growth rate, bleaching resilience, infectious disease resilience, and high sexual reproductive output. Some effort should also be reserved for underperforming genets because colonies that grow poorly in nurseries sometimes thrive once returned to the reef and may harbor genetic variants with as yet unrecognized value. Outplants should be clustered in groups of four to six genets to enable successful fertilization upon maturation. Current evidence indicates that translocating genets among distant reefs is unlikely to be problematic from a population genetic perspective but will likely provide substantial adaptive benefits. Similarly, inbreeding depression is not a concern given that current practices only raise first-generation offspring. Thus, proceeding with the proposed management strategies even in the absence of a detailed population genetic analysis of the focal species at sites targeted for restoration is the best course of action. These basic guidelines should help maximize the adaptive potential of reef-building corals facing a rapidly changing environment.
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Affiliation(s)
- Iliana B. Baums
- Department of BiologyPennsylvania State UniversityUniversity ParkPennsylvania16803USA
| | - Andrew C. Baker
- Department of Marine Biology and EcologyRosenstiel School of Marine and Atmospheric ScienceUniversity of MiamiMiamiFlorida33149USA
| | - Sarah W. Davies
- Department of BiologyBoston UniversityBostonMassachusetts02215USA
| | | | - Carly D. Kenkel
- Department of Biological SciencesUniversity of Southern CaliforniaLos AngelesCalifornia90007USA
| | - Sheila A. Kitchen
- Department of BiologyPennsylvania State UniversityUniversity ParkPennsylvania16803USA
| | - Ilsa B. Kuffner
- U.S. Geological Survey600 4th Street S.St. PetersburgFlorida33701USA
| | - Todd C. LaJeunesse
- Department of BiologyPennsylvania State UniversityUniversity ParkPennsylvania16803USA
| | - Mikhail V. Matz
- Department of Integrative BiologyThe University of Texas at AustinAustinTexas78712USA
| | | | - John E. Parkinson
- SECORE InternationalMiamiFlorida33145USA
- Department of Integrative BiologyUniversity of South FloridaTampaFlorida33620USA
| | - Andrew A. Shantz
- Department of BiologyPennsylvania State UniversityUniversity ParkPennsylvania16803USA
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