251
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Abstract
Sulfur-containing compounds are important components of all organisms, but few studies have explored sulfate utilization in corals. Our previous study found that the expression of a sulfur transporter (SLC26A11) was upregulated in the presence of Symbiodinium cells in juveniles of the reef-building coral Acropora tenuis. In this study, we performed autoradiography using 35S-labeled sulfate ions (35SO4 2−) to examine the localization and amount of incorporated radioactive sulfate in the coral tissues and symbiotic algae. Incorporated 35SO4 2− was detected in symbiotic algal cells, nematocysts, ectodermal cells and calicoblast cells. The combined results of 35S autoradiography and Alcian Blue staining showed that incorporated 35S accumulated as sulfated glycosaminoglycans (GAGs) in the ectodermal cell layer. We also compared the relative incorporation of 35SO4 2− into coral tissues and endosymbiotic algae, and their chemical fractions in dark versus light (photosynthetic) conditions. The amount of sulfur compounds, such as GAGs and lipids, generated from 35SO4 2− was higher under photosynthetic conditions. Together with the upregulation of sulfate transporters by symbiosis, our results suggest that photosynthesis of algal endosymbionts contributes to the synthesis and utilization of sulfur compounds in corals. Summary:35S-labeled sulfate incorporated into various cells of coral demonstrates that photosynthesis of endosymbiotic algae contributes to the synthesis and utilization of sulfur compounds.
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Affiliation(s)
- Ikuko Yuyama
- Center for Information Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Tomihiko Higuchi
- Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8564, Japan
| | - Yoshio Takei
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8564, Japan
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252
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Wolfowicz I, Baumgarten S, Voss PA, Hambleton EA, Voolstra CR, Hatta M, Guse A. Aiptasia sp. larvae as a model to reveal mechanisms of symbiont selection in cnidarians. Sci Rep 2016; 6:32366. [PMID: 27582179 PMCID: PMC5007887 DOI: 10.1038/srep32366] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/08/2016] [Indexed: 12/20/2022] Open
Abstract
Symbiosis, defined as the persistent association between two distinct species, is an evolutionary and ecologically critical phenomenon facilitating survival of both partners in diverse habitats. The biodiversity of coral reef ecosystems depends on a functional symbiosis with photosynthetic dinoflagellates of the highly diverse genus Symbiodinium, which reside in coral host cells and continuously support their nutrition. The mechanisms underlying symbiont selection to establish a stable endosymbiosis in non-symbiotic juvenile corals are unclear. Here we show for the first time that symbiont selection patterns for larvae of two Acropora coral species and the model anemone Aiptasia are similar under controlled conditions. We find that Aiptasia larvae distinguish between compatible and incompatible symbionts during uptake into the gastric cavity and phagocytosis. Using RNA-Seq, we identify a set of candidate genes potentially involved in symbiosis establishment. Together, our data complement existing molecular resources to mechanistically dissect symbiont phagocytosis in cnidarians under controlled conditions, thereby strengthening the role of Aiptasia larvae as a powerful model for cnidarian endosymbiosis establishment.
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Affiliation(s)
- Iliona Wolfowicz
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany
- Graduate Program in Areas of Basic and Applied Biology (GABBA), University of Porto, Porto 4200-465, Portugal
| | - Sebastian Baumgarten
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Philipp A. Voss
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany
| | | | - Christian R. Voolstra
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Masayuki Hatta
- Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo 112-8610, Japan
| | - Annika Guse
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany
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253
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Levin RA, Beltran VH, Hill R, Kjelleberg S, McDougald D, Steinberg PD, van Oppen MJH. Sex, Scavengers, and Chaperones: Transcriptome Secrets of Divergent Symbiodinium Thermal Tolerances. Mol Biol Evol 2016; 33:2201-15. [PMID: 27301593 PMCID: PMC4989115 DOI: 10.1093/molbev/msw119] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Corals rely on photosynthesis by their endosymbiotic dinoflagellates (Symbiodinium spp.) to form the basis of tropical coral reefs. High sea surface temperatures driven by climate change can trigger the loss of Symbiodinium from corals (coral bleaching), leading to declines in coral health. Different putative species (genetically distinct types) as well as conspecific populations of Symbiodinium can confer differing levels of thermal tolerance to their coral host, but the genes that govern dinoflagellate thermal tolerance are unknown. Here we show physiological and transcriptional responses to heat stress by a thermo-sensitive (physiologically susceptible at 32 °C) type C1 Symbiodinium population and a thermo-tolerant (physiologically healthy at 32 °C) type C1 Symbiodinium population. After nine days at 32 °C, neither population exhibited physiological stress, but both displayed up-regulation of meiosis genes by ≥ 4-fold and enrichment of meiosis functional gene groups, which promote adaptation. After 13 days at 32 °C, the thermo-sensitive population suffered a significant decrease in photosynthetic efficiency and increase in reactive oxygen species (ROS) leakage from its cells, whereas the thermo-tolerant population showed no signs of physiological stress. Correspondingly, only the thermo-tolerant population demonstrated up-regulation of a range of ROS scavenging and molecular chaperone genes by ≥ 4-fold and enrichment of ROS scavenging and protein-folding functional gene groups. The physiological and transcriptional responses of the Symbiodinium populations to heat stress directly correlate with the bleaching susceptibilities of corals that harbored these same Symbiodinium populations. Thus, our study provides novel, foundational insights into the molecular basis of dinoflagellate thermal tolerance and coral bleaching.
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Affiliation(s)
- Rachel A Levin
- Centre for Marine Bio-Innovation, The University of New South Wales, Sydney, NSW, Australia School of Biological Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Victor H Beltran
- Australian Institute of Marine Science, Townsville MC, QLD, Australia
| | - Ross Hill
- Macquarie University, Sydney, NSW, Australia
| | - Staffan Kjelleberg
- Centre for Marine Bio-Innovation, The University of New South Wales, Sydney, NSW, Australia Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore
| | - Diane McDougald
- Centre for Marine Bio-Innovation, The University of New South Wales, Sydney, NSW, Australia Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore The iThree Institute, University of Technology Sydney, Sydney, NSW, Australia
| | - Peter D Steinberg
- Centre for Marine Bio-Innovation, The University of New South Wales, Sydney, NSW, Australia School of Biological Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW, Australia Sydney Institute of Marine Science, Mosman, NSW, Australia
| | - Madeleine J H van Oppen
- Australian Institute of Marine Science, Townsville MC, QLD, Australia School of BioSciences, The University of Melbourne, Parkville, VIC, Australia
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254
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Price DC, Farinholt N, Gates C, Shumaker A, Wagner NE, Bienfang P, Bhattacharya D. Analysis of Gambierdiscus transcriptome data supports ancient origins of mixotrophic pathways in dinoflagellates. Environ Microbiol 2016; 18:4501-4510. [PMID: 27485969 DOI: 10.1111/1462-2920.13478] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 07/26/2016] [Accepted: 07/27/2016] [Indexed: 11/27/2022]
Abstract
Toxic dinoflagellates pose serious threats to human health and to fisheries. The genus Gambierdiscus is significant in this respect because its members produce ciguatoxin that accumulates in predominantly tropical marine food webs and leads to ciguatera fish poisoning. Understanding the biology of toxic dinoflagellates is crucial to developing control strategies. To this end, we generated a de novo transcriptome library from G. caribaeus and studied its growth under different culture conditions to elucidate pathways of carbon (C) and nitrogen (N) utilization. We also gathered available dinoflagellate transcriptome data to trace the evolutionary history of C and N pathways in this phylum. We find that rather than being specific adaptations to the epiphytic lifestyle in G. caribaeus, the majority of dinoflagellates share a large array of genes that putatively confer mixotrophy and the ability to use N via the ornithine-urea cycle and nitric oxide synthase production. These results suggest that prior to plastid endosymbiosis, the dinoflagellate ancestor possessed complex pathways that linked metabolism, intercellular signaling, and stress responses to environmental cues that have been maintained by extant photosynthetic species. This metabolic flexibility likely explains the success of dinoflagellates in marine ecosystems and may presage difficulties in controlling the spread of toxic species.
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Affiliation(s)
- Dana C Price
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Natalie Farinholt
- Center for Oceans and Human Health, Oceanography Department, School of Ocean and Earth Science and Technology, MSB no. 205, University of Hawaii, Honolulu, HI, 96822, USA
| | - Colin Gates
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Alexander Shumaker
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Nicole E Wagner
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Paul Bienfang
- Center for Oceans and Human Health, Oceanography Department, School of Ocean and Earth Science and Technology, MSB no. 205, University of Hawaii, Honolulu, HI, 96822, USA
| | - Debashish Bhattacharya
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ, 08901, USA
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255
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Mansour TA, Rosenthal JJC, Brown CT, Roberson LM. Transcriptome of the Caribbean stony coral Porites astreoides from three developmental stages. Gigascience 2016; 5:33. [PMID: 27485233 PMCID: PMC4969664 DOI: 10.1186/s13742-016-0138-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 07/14/2016] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Porites astreoides is a ubiquitous species of coral on modern Caribbean reefs that is resistant to increasing temperatures, overfishing, and other anthropogenic impacts that have threatened most other coral species. We assembled and annotated a transcriptome from this coral using Illumina sequences from three different developmental stages collected over several years: free-swimming larvae, newly settled larvae, and adults (>10 cm in diameter). This resource will aid understanding of coral calcification, larval settlement, and host-symbiont interactions. FINDINGS A de novo transcriptome for the P. astreoides holobiont (coral plus algal symbiont) was assembled using 594 Mbp of raw Illumina sequencing data generated from five age-specific cDNA libraries. The new transcriptome consists of 867 255 transcript elements with an average length of 685 bases. The isolated P. astreoides assembly consists of 129 718 transcript elements with an average length of 811 bases, and the isolated Symbiodinium sp. assembly had 186 177 transcript elements with an average length of 1105 bases. CONCLUSIONS This contribution to coral transcriptome data provides a valuable resource for researchers studying the ontogeny of gene expression patterns within both the coral and its dinoflagellate symbiont.
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Affiliation(s)
- Tamer A. Mansour
- Department of Population Health and Reproduction, University of California, Davis, California USA
- Department of Clinical Pathology, College of Medicine, Mansoura University, Mansoura, Egypt
| | - Joshua J. C. Rosenthal
- Marine Biological Laboratory, Woods Hole, Massachusetts USA
- Institute of Neurobiology, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico USA
| | - C. Titus Brown
- Department of Population Health and Reproduction, University of California, Davis, California USA
| | - Loretta M. Roberson
- Marine Biological Laboratory, Woods Hole, Massachusetts USA
- Department of Environmental Science, University of Puerto Rico Río Piedras, San Juan, Puerto Rico USA
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256
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Howells EJ, Abrego D, Meyer E, Kirk NL, Burt JA. Host adaptation and unexpected symbiont partners enable reef-building corals to tolerate extreme temperatures. GLOBAL CHANGE BIOLOGY 2016; 22:2702-14. [PMID: 26864257 DOI: 10.1111/gcb.13250] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Revised: 02/02/2016] [Accepted: 02/02/2016] [Indexed: 05/18/2023]
Abstract
Understanding the potential for coral adaptation to warming seas is complicated by interactions between symbiotic partners that define stress responses and the difficulties of tracking selection in natural populations. To overcome these challenges, we characterized the contribution of both animal host and symbiotic algae to thermal tolerance in corals that have already experienced considerable warming on par with end-of-century projections for most coral reefs. Thermal responses in Platygyra daedalea corals from the hot Persian Gulf where summer temperatures reach 36°C were compared with conspecifics from the milder Sea of Oman. Persian Gulf corals had higher rates of survival at elevated temperatures (33 and 36°C) in both the nonsymbiotic larval stage (32-49% higher) and the symbiotic adult life stage (51% higher). Additionally, Persian Gulf hosts had fixed greater potential to mitigate oxidative stress (31-49% higher) and their Symbiodinium partners had better retention of photosynthetic performance under elevated temperature (up to 161% higher). Superior thermal tolerance of Persian Gulf vs. Sea of Oman corals was maintained after 6-month acclimatization to a common ambient environment and was underpinned by genetic divergence in both the coral host and symbiotic algae. In P. daedalea host samples, genomewide SNP variation clustered into two discrete groups corresponding with Persian Gulf and Sea of Oman sites. Symbiodinium within host tissues predominantly belonged to ITS2 rDNA type C3 in the Persian Gulf and type D1a in the Sea of Oman contradicting patterns of Symbiodinium thermal tolerance from other regions. Our findings provide evidence that genetic adaptation of both host and Symbiodinium has enabled corals to cope with extreme temperatures in the Persian Gulf. Thus, the persistence of coral populations under continued warming will likely be determined by evolutionary rates in both, rather than single, symbiotic partners.
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Affiliation(s)
- Emily J Howells
- Center for Genomics and Systems Biology, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, United Arab Emirates
| | - David Abrego
- Department of Natural Science and Public Health, Zayed University, P.O. Box 144534, Abu Dhabi, United Arab Emirates
| | - Eli Meyer
- Department of Integrative Biology, Oregon State University, 3029 Cordley Hall, Corvallis, OR 97331, USA
| | - Nathan L Kirk
- Department of Integrative Biology, Oregon State University, 3029 Cordley Hall, Corvallis, OR 97331, USA
| | - John A Burt
- Center for Genomics and Systems Biology, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, United Arab Emirates
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257
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Guo R, Lim WA, Ki JS. Genome-wide analysis of transcription and photosynthesis inhibition in the harmful dinoflagellate Prorocentrum minimum in response to the biocide copper sulfate. HARMFUL ALGAE 2016; 57:27-38. [PMID: 30170719 DOI: 10.1016/j.hal.2016.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/18/2016] [Accepted: 05/19/2016] [Indexed: 06/08/2023]
Abstract
Copper is an essential trace metal for organisms; however, excess copper may damage cellular processes. Their efficiency and physiological effects of biocides have been well documented; however, molecular transcriptome responses to biocides are insufficiently studied. In the present study, a 6.0K oligonucleotide chip was developed to investigate the molecular responses of the harmful dinoflagellate Prorocentrum minimum to copper sulfate (CuSO4) treatment. The results revealed that 515 genes (approximately 8.6%) responded to CuSO4, defined as being within a 2-fold change. Further, KEGG pathway analysis showed that differentially expressed genes (DEGs) were involved in ribosomal function, RNA transport, carbon metabolism, biosynthesis of amino acids, photosystem maintenance, and other cellular processes. Among the DEGs, 49 genes were related to chloroplasts and mitochondria. Furthermore, the genes involved in the RAS signaling pathway, MAPK signaling pathway, and transport pathways were identified. An additional experiment showed that the photosynthesis efficiency decreased considerably, and reactive oxygen species (ROS) production increased in P. minimum after CuSO4 exposure. These results suggest that CuSO4 caused cellular oxidative stress in P. minimum, affecting the ribosome and mitochondria, and severely damaged the photosystem. These effects may potentially lead to cell death, although the dinoflagellate has developed a complex signal transduction process to combat copper toxicity.
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Affiliation(s)
- Ruoyu Guo
- Department of Life Science, College of Natural Sciences, Sangmyung University, Seoul 03016, Republic of Korea
| | - Weol-Ae Lim
- Oceanic Climate & Ecology Research Division, the National Institute of Fisheries Science (NISF), Busan 46083, Republic of Korea
| | - Jang-Seu Ki
- Department of Life Science, College of Natural Sciences, Sangmyung University, Seoul 03016, Republic of Korea.
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258
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Hehenberger E, Burki F, Kolisko M, Keeling PJ. Functional Relationship between a Dinoflagellate Host and Its Diatom Endosymbiont. Mol Biol Evol 2016; 33:2376-90. [DOI: 10.1093/molbev/msw109] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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259
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Orosz F. Wider than Thought Phylogenetic Occurrence of Apicortin, A Characteristic Protein of Apicomplexan Parasites. J Mol Evol 2016; 82:303-14. [PMID: 27282556 DOI: 10.1007/s00239-016-9749-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 06/04/2016] [Indexed: 11/25/2022]
Abstract
Apicomplexan parasites cause serious illnesses, including malaria, in humans and domestic animals. The presence of apicortins is predominantly characteristic of this phylum. All the apicomplexan species sequenced contain an apicortin which unites two conserved domains: DCX and partial p25alpha. This paper identifies novel apicortin orthologs in silico and corrects in several cases the erroneous sequences of hypothetical apicortin proteins of Cryptosporidium, Eimeria, and Theileria genera published in databases. Plasmodium apicortins, except from Plasmodium gallinaceum, differ significantly from the other apicomplexan apicortins. The feature of this ortholog suggests that only orthologs of Plasmodiums hosted by mammals altered significantly. The free-living Chromerida, Chromera velia, and Vitrella brassicaformis, contain three paralogs. Their apicomplexan-type and nonapicomplexan-type apicortins might be "outparalogs." The fungal ortholog, Rozella allomycis, found at protein level, and the algal Nitella mirabilis, found as Transcriptome Shotgun Assembly (TSA), are similar to the known Opisthokont (Trichoplax adhaerens, Spizellomyces punctatus) and Viridiplantae (Nicotiana tabacum) ones, since they do not contain the long, unstructured N-terminal part present in apicomplexan apicortins. A few eumetazoan animals possess apicortin-like (partial) sequences at TSA level, which may be either contaminations or the result of horizontal gene transfer; in some cases the contamination has been proved.
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Affiliation(s)
- Ferenc Orosz
- Research Centre for Natural Sciences, Institute of Enzymology, Hungarian Academy of Sciences, Magyar tudósok körútja 2, H-1117, Budapest, Hungary.
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260
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Bhattacharya D, Agrawal S, Aranda M, Baumgarten S, Belcaid M, Drake JL, Erwin D, Foret S, Gates RD, Gruber DF, Kamel B, Lesser MP, Levy O, Liew YJ, MacManes M, Mass T, Medina M, Mehr S, Meyer E, Price DC, Putnam HM, Qiu H, Shinzato C, Shoguchi E, Stokes AJ, Tambutté S, Tchernov D, Voolstra CR, Wagner N, Walker CW, Weber AP, Weis V, Zelzion E, Zoccola D, Falkowski PG. Comparative genomics explains the evolutionary success of reef-forming corals. eLife 2016; 5. [PMID: 27218454 PMCID: PMC4878875 DOI: 10.7554/elife.13288] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 04/20/2016] [Indexed: 12/30/2022] Open
Abstract
Transcriptome and genome data from twenty stony coral species and a selection of reference bilaterians were studied to elucidate coral evolutionary history. We identified genes that encode the proteins responsible for the precipitation and aggregation of the aragonite skeleton on which the organisms live, and revealed a network of environmental sensors that coordinate responses of the host animals to temperature, light, and pH. Furthermore, we describe a variety of stress-related pathways, including apoptotic pathways that allow the host animals to detoxify reactive oxygen and nitrogen species that are generated by their intracellular photosynthetic symbionts, and determine the fate of corals under environmental stress. Some of these genes arose through horizontal gene transfer and comprise at least 0.2% of the animal gene inventory. Our analysis elucidates the evolutionary strategies that have allowed symbiotic corals to adapt and thrive for hundreds of millions of years. DOI:http://dx.doi.org/10.7554/eLife.13288.001 For millions of years, reef-building stony corals have created extensive habitats for numerous marine plants and animals in shallow tropical seas. Stony corals consist of many small, tentacled animals called polyps. These polyps secrete a mineral called aragonite to create the reef – an external ‘skeleton’ that supports and protects the corals. Photosynthesizing algae live inside the cells of stony corals, and each species depends on the other to survive. The algae produce the coral’s main source of food, although they also produce some waste products that can harm the coral if they build up inside cells. If the oceans become warmer and more acidic, the coral are more likely to become stressed and expel the algae from their cells in a process known as coral bleaching. This makes the coral more likely to die or become diseased. Corals have survived previous periods of ocean warming, although it is not known how they evolved to do so. The evolutionary history of an organism can be traced by studying its genome – its complete set of DNA – and the RNA molecules encoded by these genes. Bhattacharya et al. performed this analysis for twenty stony coral species, and compared the resulting genome and RNA sequences with the genomes of other related marine organisms, such as sea anemones and sponges. In particular, Bhattacharya et al. examined “ortholog” groups of genes, which are present in different species and evolved from a common ancestral gene. This analysis identified the genes in the corals that encode the proteins responsible for constructing the aragonite skeleton. The coral genome also encodes a network of environmental sensors that coordinate how the polyps respond to temperature, light and acidity. Bhattacharya et al. also uncovered a variety of stress-related pathways, including those that detoxify the polyps of the damaging molecules generated by algae, and the pathways that enable the polyps to adapt to environmental stress. Many of these genes were recruited from other species in a process known as horizontal gene transfer. The oceans are expected to become warmer and more acidic in the coming centuries. Provided that humans do not physically destroy the corals’ habitats, the evidence found by Bhattacharya et al. suggests that the genome of the corals contains the diversity that will allow them to adapt to these new conditions. DOI:http://dx.doi.org/10.7554/eLife.13288.002
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Affiliation(s)
- Debashish Bhattacharya
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, United States.,Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, United States
| | - Shobhit Agrawal
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Manuel Aranda
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Sebastian Baumgarten
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Mahdi Belcaid
- Hawaii Institute of Marine Biology, Kaneohe, United States
| | - Jeana L Drake
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, United States
| | - Douglas Erwin
- Smithsonian Institution, National Museum of Natural History, Washington, United States
| | - Sylvian Foret
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia.,Research School of Biology, Australian National University, Canberra, Australia
| | - Ruth D Gates
- Hawaii Institute of Marine Biology, Kaneohe, United States
| | - David F Gruber
- American Museum of Natural History, Sackler Institute for Comparative Genomics, New York, United States.,Department of Natural Sciences, City University of New York, Baruch College and The Graduate Center, New York, United States
| | - Bishoy Kamel
- Department of Biology, Mueller Lab, Penn State University, University Park, United States
| | - Michael P Lesser
- School of Marine Science and Ocean Engineering, University of New Hampshire, Durham, United States
| | - Oren Levy
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gam, Israel
| | - Yi Jin Liew
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Matthew MacManes
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, United States
| | - Tali Mass
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, United States.,Marine Biology Department, The Leon H. Charney School of Marine Sciences, University of Haifa, Mt. Carmel, Israel
| | - Monica Medina
- Department of Biology, Mueller Lab, Penn State University, University Park, United States
| | - Shaadi Mehr
- American Museum of Natural History, Sackler Institute for Comparative Genomics, New York, United States.,Biological Science Department, State University of New York, College at Old Westbury, New York, United States
| | - Eli Meyer
- Department of Integrative Biology, Oregon State University, Corvallis, United States
| | - Dana C Price
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, United States
| | | | - Huan Qiu
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, United States
| | - Chuya Shinzato
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Eiichi Shoguchi
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Alexander J Stokes
- Laboratory of Experimental Medicine and Department of Cell and Molecular Biology, John A. Burns School of Medicine, Honolulu, United States.,Chaminade University, Honolulu, United States
| | | | - Dan Tchernov
- Marine Biology Department, The Leon H. Charney School of Marine Sciences, University of Haifa, Mt. Carmel, Israel
| | - Christian R Voolstra
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Nicole Wagner
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, United States
| | - Charles W Walker
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, United States
| | - Andreas Pm Weber
- Institute of Plant Biochemistry, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Virginia Weis
- Department of Integrative Biology, Oregon State University, Corvallis, United States
| | - Ehud Zelzion
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, United States
| | | | - Paul G Falkowski
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, United States.,Department of Earth and Planetary Sciences, Rutgers University, New Jersey, United States
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261
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Howells EJ, Willis BL, Bay LK, van Oppen MJH. Microsatellite allele sizes alone are insufficient to delineate species boundaries inSymbiodinium. Mol Ecol 2016; 25:2719-23. [DOI: 10.1111/mec.13631] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/10/2016] [Accepted: 03/29/2016] [Indexed: 11/29/2022]
Affiliation(s)
- E. J. Howells
- Center for Genomics and Systems Biology; New York University Abu Dhabi; Saadiyat Island Abu Dhabi United Arab Emirates
| | - B. L. Willis
- ARC Centre of Excellence for Coral Reef Studies and College of Marine and Environmental Sciences; James Cook University; Townsville Qld 4811 Australia
| | - L. K. Bay
- Australian Institute of Marine Science; PMB 3 MC Townsville Qld 4810 Australia
| | - M. J. H. van Oppen
- Australian Institute of Marine Science; PMB 3 MC Townsville Qld 4810 Australia
- School of Biosciences; The University of Melbourne; Parkville Vic. 3052 Australia
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262
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Cooper JT, Sinclair GA, Wawrik B. Transcriptome Analysis of Scrippsiella trochoidea CCMP 3099 Reveals Physiological Changes Related to Nitrate Depletion. Front Microbiol 2016; 7:639. [PMID: 27242681 PMCID: PMC4860509 DOI: 10.3389/fmicb.2016.00639] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 04/18/2016] [Indexed: 01/25/2023] Open
Abstract
Dinoflagellates are a major component of marine phytoplankton and many species are recognized for their ability to produce harmful algal blooms (HABs). Scrippsiella trochoidea is a non-toxic, marine dinoflagellate that can be found in both cold and tropic waters where it is known to produce “red tide” events. Little is known about the genomic makeup of S. trochoidea and a transcriptome study was conducted to shed light on the biochemical and physiological adaptations related to nutrient depletion. Cultures were grown under N and P limiting conditions and transcriptomes were generated via RNAseq technology. De novo assembly reconstructed 107,415 putative transcripts of which only 41% could be annotated. No significant transcriptomic response was observed in response to initial P depletion, however, a strong transcriptional response to N depletion was detected. Among the down-regulated pathways were those for glutamine/glutamate metabolism as well as urea and nitrate/nitrite transporters. Transcripts for ammonia transporters displayed both up- and down-regulation, perhaps related to a shift to higher affinity transporters. Genes for the utilization of DON compounds were up-regulated. These included transcripts for amino acids transporters, polyamine oxidase, and extracellular proteinase and peptidases. N depletion also triggered down regulation of transcripts related to the production of Photosystems I & II and related proteins. These data are consistent with a metabolic strategy that conserves N while maximizing sustained metabolism by emphasizing the relative contribution of organic N sources. Surprisingly, the transcriptome also contained transcripts potentially related to secondary metabolite production, including a homolog to the Short Isoform Saxitoxin gene (sxtA) from Alexandrium fundyense, which was significantly up-regulated under N-depletion. A total of 113 unique hits to Sxt genes, covering 17 of the 34 genes found in C. raciborskii were detected, indicating that S. trochoidea has previously unrecognized potential for the production of secondary metabolites with potential toxicity.
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Affiliation(s)
- Joshua T Cooper
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
| | - Geoffrey A Sinclair
- Department of Marine, Earth and Atmospheric Sciences, North Carolina State University Raleigh, NC, USA
| | - Boris Wawrik
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
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263
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Bellis ES, Howe DK, Denver DR. Genome-wide polymorphism and signatures of selection in the symbiotic sea anemone Aiptasia. BMC Genomics 2016; 17:160. [PMID: 26926343 PMCID: PMC4772690 DOI: 10.1186/s12864-016-2488-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 02/17/2016] [Indexed: 12/30/2022] Open
Abstract
Background Coral reef ecosystems are declining in response to global climate change and anthropogenic impacts. Yet patterns of standing genetic variation within cnidarian species, a major determinant of adaptive potential, are virtually unknown at genome-scale resolution. We explore patterns of genome-wide polymorphism and identify candidate loci under selection in the sea anemone Aiptasia, an important laboratory model system for studying the symbiosis between corals and dinoflagellate algae of the genus Symbiodinium. Results Low coverage genome sequencing revealed large genetic distances among globally widespread lineages, novel candidate targets of selection, and considerably higher heterozygosity than previously reported for Aiptasia. More than 670,000 single nucleotide polymorphisms were identified among 10 Aiptasia individuals including two pairs of genetic clones. Evolutionary relationships based on genome-wide polymorphism supported the current paradigm of a genetically distinct population from the US South Atlantic that harbors diverse Symbiodinium clades. However, anemones from the US South Atlantic demonstrated a striking lack of shared derived polymorphism. Heterozygosity was an important feature shaping nucleotide diversity patterns: at any given SNP site, more than a third of individuals genotyped were heterozygotes, and heterozygosity within individual genomes ranged from 0.37–0.58 %. Analysis of nonsynonymous and synonymous sites suggested that highly heterozygous regions are evolving under relaxed purifying selection compared to the rest of the Aiptasia genome. Genes previously identified as having elevated evolutionary rates in Aiptasia compared to other cnidarians were found in our study to be under strong purifying selection within Aiptasia. Candidate targets of selection, including lectins and genes involved in Rho GTPase signalling, were identified based on unusual signatures of nucleotide diversity, Tajima’s D, and heterozygosity compared to genome-wide averages. Conclusions This study represents the first genome-wide analysis of Tajima’s D in a cnidarian. Our results shed light on patterns of intraspecific genome-wide polymorphism in a model for studies of coral-algae symbiosis and present genetic targets for future research on evolutionary and cellular processes in early-diverging metazoans. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2488-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Emily S Bellis
- Department of Integrative Biology, Oregon State University, Corvallis, 97331, OR, USA.
| | - Dana K Howe
- Department of Integrative Biology, Oregon State University, Corvallis, 97331, OR, USA.
| | - Dee R Denver
- Department of Integrative Biology, Oregon State University, Corvallis, 97331, OR, USA.
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264
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Anderson DA, Walz ME, Weil E, Tonellato P, Smith MC. RNA-Seq of the Caribbean reef-building coral Orbicella faveolata (Scleractinia-Merulinidae) under bleaching and disease stress expands models of coral innate immunity. PeerJ 2016; 4:e1616. [PMID: 26925311 PMCID: PMC4768675 DOI: 10.7717/peerj.1616] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 01/01/2016] [Indexed: 12/16/2022] Open
Abstract
Climate change-driven coral disease outbreaks have led to widespread declines in coral populations. Early work on coral genomics established that corals have a complex innate immune system, and whole-transcriptome gene expression studies have revealed mechanisms by which the coral immune system responds to stress and disease. The present investigation expands bioinformatic data available to study coral molecular physiology through the assembly and annotation of a reference transcriptome of the Caribbean reef-building coral, Orbicella faveolata. Samples were collected during a warm water thermal anomaly, coral bleaching event and Caribbean yellow band disease outbreak in 2010 in Puerto Rico. Multiplex sequencing of RNA on the Illumina GAIIx platform and de novo transcriptome assembly by Trinity produced 70,745,177 raw short-sequence reads and 32,463 O. faveolata transcripts, respectively. The reference transcriptome was annotated with gene ontologies, mapped to KEGG pathways, and a predicted proteome of 20,488 sequences was generated. Protein families and signaling pathways that are essential in the regulation of innate immunity across Phyla were investigated in-depth. Results were used to develop models of evolutionarily conserved Wnt, Notch, Rig-like receptor, Nod-like receptor, and Dicer signaling. O. faveolata is a coral species that has been studied widely under climate-driven stress and disease, and the present investigation provides new data on the genes that putatively regulate its immune system.
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Affiliation(s)
- David A Anderson
- Department of Pathology and Immunology, Washington University in St. Louis, St. Louis, Missouri, United States of America; Department of Marine Sciences, University of Puerto Rico at Mayagüez, Mayagüez, Puerto Rico, United States of America
| | - Marcus E Walz
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin , United States of America
| | - Ernesto Weil
- Department of Marine Sciences, University of Puerto Rico at Mayagüez , Mayagüez, Puerto Rico , United States of America
| | - Peter Tonellato
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, United States of America; Department of Biomedical Informatics, Harvard Medical School, Harvard University, Boston, Massachusetts, United States of America
| | - Matthew C Smith
- School of Freshwater Sciences, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin , United States of America
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265
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Parkinson JE, Baumgarten S, Michell CT, Baums IB, LaJeunesse TC, Voolstra CR. Gene Expression Variation Resolves Species and Individual Strains among Coral-Associated Dinoflagellates within the Genus Symbiodinium. Genome Biol Evol 2016; 8:665-80. [PMID: 26868597 PMCID: PMC4824173 DOI: 10.1093/gbe/evw019] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Reef-building corals depend on symbiotic mutualisms with photosynthetic dinoflagellates in the genus Symbiodinium. This large microalgal group comprises many highly divergent lineages (“Clades A–I”) and hundreds of undescribed species. Given their ecological importance, efforts have turned to genomic approaches to characterize the functional ecology of Symbiodinium. To date, investigators have only compared gene expression between representatives from separate clades—the equivalent of contrasting genera or families in other dinoflagellate groups—making it impossible to distinguish between clade-level and species-level functional differences. Here, we examined the transcriptomes of four species within one Symbiodinium clade (Clade B) at ∼20,000 orthologous genes, as well as multiple isoclonal cell lines within species (i.e., cultured strains). These species span two major adaptive radiations within Clade B, each encompassing both host-specialized and ecologically cryptic taxa. Species-specific expression differences were consistently enriched for photosynthesis-related genes, likely reflecting selection pressures driving niche diversification. Transcriptional variation among strains involved fatty acid metabolism and biosynthesis pathways. Such differences among individuals are potentially a major source of physiological variation, contributing to the functional diversity of coral holobionts composed of unique host–symbiont genotype pairings. Our findings expand the genomic resources available for this important symbiont group and emphasize the power of comparative transcriptomics as a method for studying speciation processes and interindividual variation in nonmodel organisms.
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Affiliation(s)
| | - Sebastian Baumgarten
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Craig T Michell
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | | | | | - Christian R Voolstra
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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266
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Oakley CA, Ameismeier MF, Peng L, Weis VM, Grossman AR, Davy SK. Symbiosis induces widespread changes in the proteome of the model cnidarianAiptasia. Cell Microbiol 2016; 18:1009-23. [DOI: 10.1111/cmi.12564] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 12/17/2015] [Accepted: 12/22/2015] [Indexed: 01/06/2023]
Affiliation(s)
- Clinton A. Oakley
- School of Biological Sciences; Victoria University of Wellington; Wellington 6012 New Zealand
| | - Michael F. Ameismeier
- Gene Center, Department of Chemistry and Biochemistry; University of Munich; Munich 81377 Germany
| | - Lifeng Peng
- School of Biological Sciences; Victoria University of Wellington; Wellington 6012 New Zealand
| | - Virginia M. Weis
- Department of Integrative Biology; Oregon State University; Corvallis OR 97331 USA
| | - Arthur R. Grossman
- Department of Plant Biology; The Carnegie Institution; Stanford CA 94305 USA
| | - Simon K. Davy
- School of Biological Sciences; Victoria University of Wellington; Wellington 6012 New Zealand
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267
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Development and Symbiosis Establishment in the Cnidarian Endosymbiosis Model Aiptasia sp. Sci Rep 2016; 6:19867. [PMID: 26804034 PMCID: PMC4726165 DOI: 10.1038/srep19867] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 12/16/2015] [Indexed: 12/19/2022] Open
Abstract
Symbiosis between photosynthetic algae and heterotrophic organisms is widespread. One prominent example of high ecological relevance is the endosymbiosis between dinoflagellate algae of the genus Symbiodinium and reef-building corals, which typically acquire symbionts anew each generation during larval stages. The tropical sea anemone Aiptasia sp. is a laboratory model system for this endosymbiosis and, similar to corals, produces non-symbiotic larvae that establish symbiosis by phagocytosing Symbiodinium from the environment into the endoderm. Here we generate the first overview of Aiptasia embryogenesis and larval development and establish in situ hybridization to analyze expression patterns of key early developmental regulators. Next, we quantify morphological changes in developing larvae and find a substantial enlargement of the gastric cavity over time. Symbiont acquisition starts soon after mouth formation and symbionts occupy a major portion of the host cell in which they reside. During the first 14 days of development, infection efficiency remains constant while in contrast, localization of phagocytosed symbionts changes, indicating that the occurrence of functional phagocytosing cells may be developmentally regulated. Taken together, here we provide the essential framework to further develop Aiptasia as a model system for the analysis of symbiosis establishment in cnidarian larvae at the molecular level.
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268
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Butterfield ER, Howe CJ, Nisbet RER. Identification of Sequences Encoding Symbiodinium minutum Mitochondrial Proteins. Genome Biol Evol 2016; 8:439-45. [PMID: 26798115 PMCID: PMC4779609 DOI: 10.1093/gbe/evw002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The dinoflagellates are an extremely diverse group of algae closely related to the Apicomplexa and the ciliates. Much work has previously been undertaken to determine the presence of various biochemical pathways within dinoflagellate mitochondria. However, these studies were unable to identify several key transcripts including those encoding proteins involved in the pyruvate dehydrogenase complex, iron–sulfur cluster biosynthesis, and protein import. Here, we analyze the draft nuclear genome of the dinoflagellate Symbiodinium minutum, as well as RNAseq data to identify nuclear genes encoding mitochondrial proteins. The results confirm the presence of a complete tricarboxylic acid cycle in the dinoflagellates. Results also demonstrate the difficulties in using the genome sequence for the identification of genes due to the large number of introns, but show that it is highly useful for the determination of gene duplication events.
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Affiliation(s)
- Erin R Butterfield
- School of Pharmacy and Medical Sciences, Sansom Institute for Health Research, University of South Australia, North Terrace, Adelaide, SA, Australia Department of Biochemistry, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom
| | - Christopher J Howe
- Department of Biochemistry, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom
| | - R Ellen R Nisbet
- School of Pharmacy and Medical Sciences, Sansom Institute for Health Research, University of South Australia, North Terrace, Adelaide, SA, Australia Department of Biochemistry, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom
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269
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Guo R, Wang H, Suh YS, Ki JS. Transcriptomic profiles reveal the genome-wide responses of the harmful dinoflagellate Cochlodinium polykrikoides when exposed to the algicide copper sulfate. BMC Genomics 2016; 17:29. [PMID: 26732698 PMCID: PMC4702327 DOI: 10.1186/s12864-015-2341-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 12/22/2015] [Indexed: 11/29/2022] Open
Abstract
Background Harmful algal blooms (HABs) caused by the dinoflagellate Cochlodinium polykrikoides lead to severe environmental impacts in oceans worldwide followed by huge economic losses. Algicide agent copper sulfate (CuSO4) is regard as an economical and effective agent for HABs mitigation; its biochemical and physiological effects were revealed in C. polykrikoides. However, molecular mechanisms of CuSO4 effect on the C. polykrikoides, even other HAB species, have not been investigated. The present study investigated the transcriptional response of C. polykrikoides against CuSO4 treatments, with the aim of providing certain molecular mechanism of CuSO4 effect on the C. polykrikoides blooms. Results RNA-seq generated 173 million reads, which were further assembled to 191,212 contigs. 43.3 %, 33.9 %, and 15.6 % of contigs were annotated with NCBI NR, GO, and KEGG database, respectively. Transcriptomic analysis revealed 20.6 % differential expressed contigs, which grouped into 8 clusters according to K-means clustering analysis, responding to CuSO4; 848 contigs were up-regulated and 746 contigs were down-regulated more than 2-fold changes from 12 h to 48 h exposure. KEGG pathway analysis of eukaryotic homologous genes revealed the differentially expressed genes (DEGs) were involved in diverse pathway; amongst, the genes involved in the translation, spliceosome, and/or signal transduction genes were highly regulated. Most of photosystem related genes were down-regulated and most of mitochondria related genes were up-regulated. In addition, the genes involved in the copper ion binding or transporting and antioxidant systems were identified. Measurement of chlorophyll fluorescence showed that photosynthesis was significantly inhibited by CuSO4 exposure. Conclusions This study reported the first transcriptome of the C. polykrikoides. The widely differential expressed photosystem genes suggested photosynthetic machinery were severely affected, and may further contribute to the cell death. Furthermore, gene translation and transcription processes may be disrupted, inhibiting cell growth and proliferation, and possibly accelerating cell death. However, antioxidant systems resistant to CuSO4 caused stress; mitochondrion may compensate for photosynthesis efficiency decreasing caused energy deficiency. In addition, various signal transduction pathways may be involved in the CuSO4 induced regulation network in the C. polykrikoides. These data provide the potential transcriptomic mechanism to explain the algicide CuSO4 effect on the harmful dinoflagellate C. polykrikoides. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2341-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ruoyu Guo
- Department of Life Science, College of Natural Sciences, Sangmyung University, Seoul, 110-743, Korea.
| | - Hui Wang
- Department of Life Science, College of Natural Sciences, Sangmyung University, Seoul, 110-743, Korea
| | - Young Sang Suh
- Fishery and Ocean Information Division, National Fisheries Research & Development Institute, Busan, 619-705, Korea.
| | - Jang-Seu Ki
- Department of Life Science, College of Natural Sciences, Sangmyung University, Seoul, 110-743, Korea.
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270
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Bosch TCG, Miller DJ. Major Events in the Evolution of Planet Earth: Some Origin Stories. THE HOLOBIONT IMPERATIVE 2016. [PMCID: PMC7121852 DOI: 10.1007/978-3-7091-1896-2_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
With billions of years of evolution before the appearance of animals, prokaryotes shaped and continue to shape both the Earth’s biogeochemical landscape and the setting for animal existence (Fig. 2.1) (Knoll 2003).
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271
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Animal–Symbiodinium Symbioses: Foundations of Coral Reef Ecosystems. ADVANCES IN ENVIRONMENTAL MICROBIOLOGY 2016. [DOI: 10.1007/978-3-319-28068-4_10] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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272
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273
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Abstract
Histone proteins and the nucleosomal organization of chromatin are near-universal eukaroytic features, with the exception of dinoflagellates. Previous studies have suggested that histones do not play a major role in the packaging of dinoflagellate genomes, although several genomic and transcriptomic surveys have detected a full set of core histone genes. Here, transcriptomic and genomic sequence data from multiple dinoflagellate lineages are analyzed, and the diversity of histone proteins and their variants characterized, with particular focus on their potential post-translational modifications and the conservation of the histone code. In addition, the set of putative epigenetic mark readers and writers, chromatin remodelers and histone chaperones are examined. Dinoflagellates clearly express the most derived set of histones among all autonomous eukaryote nuclei, consistent with a combination of relaxation of sequence constraints imposed by the histone code and the presence of numerous specialized histone variants. The histone code itself appears to have diverged significantly in some of its components, yet others are conserved, implying conservation of the associated biochemical processes. Specifically, and with major implications for the function of histones in dinoflagellates, the results presented here strongly suggest that transcription through nucleosomal arrays happens in dinoflagellates. Finally, the plausible roles of histones in dinoflagellate nuclei are discussed.
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274
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Lin S, Cheng S, Song B, Zhong X, Lin X, Li W, Li L, Zhang Y, Zhang H, Ji Z, Cai M, Zhuang Y, Shi X, Lin L, Wang L, Wang Z, Liu X, Yu S, Zeng P, Hao H, Zou Q, Chen C, Li Y, Wang Y, Xu C, Meng S, Xu X, Wang J, Yang H, Campbell DA, Sturm NR, Dagenais-Bellefeuille S, Morse D. The Symbiodinium kawagutii genome illuminates dinoflagellate gene expression and coral symbiosis. Science 2015; 350:691-4. [PMID: 26542574 DOI: 10.1126/science.aad0408] [Citation(s) in RCA: 278] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Dinoflagellates are important components of marine ecosystems and essential coral symbionts, yet little is known about their genomes. We report here on the analysis of a high-quality assembly from the 1180-megabase genome of Symbiodinium kawagutii. We annotated protein-coding genes and identified Symbiodinium-specific gene families. No whole-genome duplication was observed, but instead we found active (retro)transposition and gene family expansion, especially in processes important for successful symbiosis with corals. We also documented genes potentially governing sexual reproduction and cyst formation, novel promoter elements, and a microRNA system potentially regulating gene expression in both symbiont and coral. We found biochemical complementarity between genomes of S. kawagutii and the anthozoan Acropora, indicative of host-symbiont coevolution, providing a resource for studying the molecular basis and evolution of coral symbiosis.
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Affiliation(s)
- Senjie Lin
- State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Global Change Research Center, Xiamen University, Xiamen 361101, China. Department of Marine Sciences, University of Connecticut, Groton, CT 06340, USA.
| | - Shifeng Cheng
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China. Hong Kong University (HKU)-BGI Bioinformatics Algorithms and Core Technology Research Laboratory, The Computer Science Department, The University of Hong Kong, Hong Kong, China. School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Bo Song
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Xiao Zhong
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Xin Lin
- State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Global Change Research Center, Xiamen University, Xiamen 361101, China
| | - Wujiao Li
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Ling Li
- State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Global Change Research Center, Xiamen University, Xiamen 361101, China
| | - Yaqun Zhang
- State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Global Change Research Center, Xiamen University, Xiamen 361101, China
| | - Huan Zhang
- Department of Marine Sciences, University of Connecticut, Groton, CT 06340, USA
| | - Zhiliang Ji
- State Key Laboratory of Stress Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Meichun Cai
- State Key Laboratory of Stress Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Yunyun Zhuang
- Department of Marine Sciences, University of Connecticut, Groton, CT 06340, USA
| | - Xinguo Shi
- State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Global Change Research Center, Xiamen University, Xiamen 361101, China
| | - Lingxiao Lin
- State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Global Change Research Center, Xiamen University, Xiamen 361101, China
| | - Lu Wang
- State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Global Change Research Center, Xiamen University, Xiamen 361101, China
| | - Zhaobao Wang
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Xin Liu
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Sheng Yu
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Peng Zeng
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Han Hao
- Bioinformatics Institute, Agency for Science, Technology and Research, Singapore
| | - Quan Zou
- State Key Laboratory of Stress Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361101, China
| | - Chengxuan Chen
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Yanjun Li
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Ying Wang
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Chunyan Xu
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Shanshan Meng
- State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Global Change Research Center, Xiamen University, Xiamen 361101, China
| | - Xun Xu
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China
| | - Jun Wang
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China. Department of Biology, University of Copenhagen, DK-2200 Copenhagen, Denmark. Princess Al Jawhara Center of Excellence in the Research of Hereditary Disorders, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Huanming Yang
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, 518083, China. Princess Al Jawhara Center of Excellence in the Research of Hereditary Disorders, King Abdulaziz University, Jeddah, Saudi Arabia. James D. Watson Institute of Genome Science, Hangzhou, China
| | - David A Campbell
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Nancy R Sturm
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Steve Dagenais-Bellefeuille
- Institut de Recherche en Biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Montréal, Canada
| | - David Morse
- Institut de Recherche en Biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Montréal, Canada
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275
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Shelest E, Heimerl N, Fichtner M, Sasso S. Multimodular type I polyketide synthases in algae evolve by module duplications and displacement of AT domains in trans. BMC Genomics 2015; 16:1015. [PMID: 26611533 PMCID: PMC4661987 DOI: 10.1186/s12864-015-2222-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 11/16/2015] [Indexed: 11/16/2022] Open
Abstract
Background Polyketide synthase (PKS) catalyzes the biosynthesis of polyketides, which are structurally and functionally diverse natural products in microorganisms and plants. Here, we have analyzed available full genome sequences of microscopic and macroscopic algae for the presence of type I PKS genes. Results Type I PKS genes are present in 15 of 32 analyzed algal species. In chlorophytes, large proteins in the MDa range are predicted in most sequenced species, and PKSs with free-standing acyltransferase domains (trans-AT PKSs) predominate. In a phylogenetic tree, PKS sequences from different algal phyla form clades that are distinct from PKSs from other organisms such as non-photosynthetic protists or cyanobacteria. However, intermixing is observed in some cases, for example polyunsaturated fatty acid (PUFA) and glycolipid synthases of various origins. Close relationships between type I PKS modules from different species or between modules within the same multimodular enzyme were identified, suggesting module duplications during evolution of algal PKSs. In contrast to type I PKSs, nonribosomal peptide synthetases (NRPSs) are relatively rare in algae (occurrence in 7 of 32 species). Conclusions Our phylogenetic analysis of type I PKSs in algae supports an evolutionary scenario whereby integrated AT domains were displaced to yield trans-AT PKSs. Together with module duplications, the displacement of AT domains may constitute a major mechanism of PKS evolution in algae. This study advances our understanding of the diversity of eukaryotic PKSs and their evolutionary trajectories. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2222-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ekaterina Shelest
- Research Group Systems Biology/Bioinformatics, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstr. 11a, 07745, Jena, Germany.
| | - Natalie Heimerl
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, Dornburger Str. 159, 07743, Jena, Germany.
| | - Maximilian Fichtner
- Research Group Systems Biology/Bioinformatics, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstr. 11a, 07745, Jena, Germany.
| | - Severin Sasso
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, Dornburger Str. 159, 07743, Jena, Germany.
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276
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Beedessee G, Hisata K, Roy MC, Satoh N, Shoguchi E. Multifunctional polyketide synthase genes identified by genomic survey of the symbiotic dinoflagellate, Symbiodinium minutum. BMC Genomics 2015; 16:941. [PMID: 26573520 PMCID: PMC4647583 DOI: 10.1186/s12864-015-2195-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 11/05/2015] [Indexed: 11/17/2022] Open
Abstract
Background Dinoflagellates are unicellular marine and freshwater eukaryotes. They possess large nuclear genomes (1.5–245 gigabases) and produce structurally unique and biologically active polyketide secondary metabolites. Although polyketide biosynthesis is well studied in terrestrial and freshwater organisms, only recently have dinoflagellate polyketides been investigated. Transcriptomic analyses have characterized dinoflagellate polyketide synthase genes having single domains. The Genus Symbiodinium, with a comparatively small genome, is a group of major coral symbionts, and the S. minutum nuclear genome has been decoded. Results The present survey investigated the assembled S. minutum genome and identified 25 candidate polyketide synthase (PKS) genes that encode proteins with mono- and multifunctional domains. Predicted proteins retain functionally important amino acids in the catalytic ketosynthase (KS) domain. Molecular phylogenetic analyses of KS domains form a clade in which S. minutum domains cluster within the protist Type I PKS clade with those of other dinoflagellates and other eukaryotes. Single-domain PKS genes are likely expanded in dinoflagellate lineage. Two PKS genes of bacterial origin are found in the S. minutum genome. Interestingly, the largest enzyme is likely expressed as a hybrid non-ribosomal peptide synthetase-polyketide synthase (NRPS-PKS) assembly of 10,601 amino acids, containing NRPS and PKS modules and a thioesterase (TE) domain. We also found intron-rich genes with the minimal set of catalytic domains needed to produce polyketides. Ketosynthase (KS), acyltransferase (AT), and acyl carrier protein (ACP) along with other optional domains are present. Mapping of transcripts to the genome with the dinoflagellate-specific spliced leader sequence, supports expression of multifunctional PKS genes. Metabolite profiling of cultured S. minutum confirmed production of zooxanthellamide D, a polyhydroxy amide polyketide and other unknown polyketide secondary metabolites. Conclusion This genomic survey demonstrates that S. minutum contains genes with the minimal set of catalytic domains needed to produce polyketides and provides evidence of the modular nature of Type I PKS, unlike monofunctional Type I PKS from other dinoflagellates. In addition, our study suggests that diversification of dinoflagellate PKS genes comprises dinoflagellate-specific PKS genes with single domains, multifunctional PKS genes with KS domains orthologous to those of other protists, and PKS genes of bacterial origin. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2195-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Girish Beedessee
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan.
| | - Kanako Hisata
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan.
| | - Michael C Roy
- Imaging and Instrumental Analysis Section, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan.
| | - Noriyuki Satoh
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan.
| | - Eiichi Shoguchi
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan.
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277
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Transcriptomic Changes in Coral Holobionts Provide Insights into Physiological Challenges of Future Climate and Ocean Change. PLoS One 2015; 10:e0139223. [PMID: 26510159 PMCID: PMC4624983 DOI: 10.1371/journal.pone.0139223] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 09/09/2015] [Indexed: 01/01/2023] Open
Abstract
Tropical reef-building coral stress levels will intensify with the predicted rising atmospheric CO2 resulting in ocean temperature and acidification increase. Most studies to date have focused on the destabilization of coral-dinoflagellate symbioses due to warming oceans, or declining calcification due to ocean acidification. In our study, pH and temperature conditions consistent with the end-of-century scenarios of the Intergovernmental Panel on Climate Change (IPCC) caused major changes in photosynthesis and respiration, in addition to decreased calcification rates in the coral Acropora millepora. Population density of symbiotic dinoflagellates (Symbiodinium) under high levels of ocean acidification and temperature (Representative Concentration Pathway, RCP8.5) decreased to half of that found under present day conditions, with photosynthetic and respiratory rates also being reduced by 40%. These physiological changes were accompanied by evidence for gene regulation of calcium and bicarbonate transporters along with components of the organic matrix. Metatranscriptomic RNA-Seq data analyses showed an overall down regulation of metabolic transcripts, and an increased abundance of transcripts involved in circadian clock control, controlling the damage of oxidative stress, calcium signaling/homeostasis, cytoskeletal interactions, transcription regulation, DNA repair, Wnt signaling and apoptosis/immunity/ toxins. We suggest that increased maintenance costs under ocean acidification and warming, and diversion of cellular ATP to pH homeostasis, oxidative stress response, UPR and DNA repair, along with metabolic suppression, may underpin why Acroporid species tend not to thrive under future environmental stress. Our study highlights the potential increased energy demand when the coral holobiont is exposed to high levels of ocean warming and acidification.
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278
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Grawunder D, Hambleton EA, Bucher M, Wolfowicz I, Bechtoldt N, Guse A. Induction of Gametogenesis in the Cnidarian Endosymbiosis Model Aiptasia sp. Sci Rep 2015; 5:15677. [PMID: 26498008 PMCID: PMC4620495 DOI: 10.1038/srep15677] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 10/01/2015] [Indexed: 12/31/2022] Open
Abstract
Endosymbiosis is widespread among cnidarians and is of high ecological relevance. The tropical sea anemone Aiptasia sp. is a laboratory model system for endosymbiosis between reef-building corals and photosynthetic dinoflagellate algae of the genus Symbiodinium. Here we identify the key environmental cues to induce reproducible spawning in Aiptasia under controlled laboratory conditions. We find that simulating a lunar cycle with blue-wavelength light is necessary to promote abundant gamete production and synchronous release in well-fed animals. Sexual reproduction rates are genetically determined and differ among clonal lines under similar conditions. We also find the inverse difference in rates of asexual reproduction. This study provides the requisite basis for further development of the Aiptasia model system, allowing analysis of basic cellular and molecular mechanisms in the laboratory as well as investigations of broad questions of ecological and evolutionary relevance.
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Affiliation(s)
- Désirée Grawunder
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany
| | - Elizabeth A Hambleton
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany
| | - Madeline Bucher
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany
| | - Iliona Wolfowicz
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany.,University of Porto, Porto 4200-465, Portugal
| | - Natascha Bechtoldt
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany
| | - Annika Guse
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg 69120, Germany
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279
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Gacesa R, Chung R, Dunn SR, Weston AJ, Jaimes-Becerra A, Marques AC, Morandini AC, Hranueli D, Starcevic A, Ward M, Long PF. Gene duplications are extensive and contribute significantly to the toxic proteome of nematocysts isolated from Acropora digitifera (Cnidaria: Anthozoa: Scleractinia). BMC Genomics 2015; 16:774. [PMID: 26464356 PMCID: PMC4604070 DOI: 10.1186/s12864-015-1976-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 10/03/2015] [Indexed: 11/10/2022] Open
Abstract
Background Gene duplication followed by adaptive selection is a well-accepted process leading to toxin diversification in venoms. However, emergent genomic, transcriptomic and proteomic evidence now challenges this role to be at best equivocal to other processess . Cnidaria are arguably the most ancient phylum of the extant metazoa that are venomous and such provide a definitive ancestral anchor to examine the evolution of this trait. Methods Here we compare predicted toxins from the translated genome of the coral Acropora digitifera to putative toxins revealed by proteomic analysis of soluble proteins discharged from nematocysts, to determine the extent to which gene duplications contribute to venom innovation in this reef-building coral species. A new bioinformatics tool called HHCompare was developed to detect potential gene duplications in the genomic data, which is made freely available (https://github.com/rgacesa/HHCompare). Results A total of 55 potential toxin encoding genes could be predicted from the A. digitifera genome, of which 36 (65 %) had likely arisen by gene duplication as evinced using the HHCompare tool and verified using two standard phylogeny methods. Surprisingly, only 22 % (12/55) of the potential toxin repertoire could be detected following rigorous proteomic analysis, for which only half (6/12) of the toxin proteome could be accounted for as peptides encoded by the gene duplicates. Biological activities of these toxins are dominatedby putative phospholipases and toxic peptidases. Conclusions Gene expansions in A. digitifera venom are the most extensive yet described in any venomous animal, and gene duplication plays a significant role leading to toxin diversification in this coral species. Since such low numbers of toxins were detected in the proteome, it is unlikely that the venom is evolving rapidly by prey-driven positive natural selection. Rather we contend that the venom has a defensive role deterring predation or harm from interspecific competition and overgrowth by fouling organisms. Factors influencing translation of toxin encoding genes perhaps warrants more profound experimental consideration. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1976-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ranko Gacesa
- Institute of Pharmaceutical Science, King's College London, 150 Stamford Street, London, SE1 9NH, UK
| | - Ray Chung
- Proteomics Facility, Institute of Psychiatry, Psychology & Neuroscience, King's College London, 16 De Crespigny Park, London, SE5 8AF, UK
| | - Simon R Dunn
- Coral Reefs Ecosystems Laboratory, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Andrew J Weston
- Mass Spectrometry Laboratory, UCL School of Pharmacy, 29/39 Brunswick Square, London, WC1N 1AX, UK
| | - Adrian Jaimes-Becerra
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, Rua Matao, Trav. 14, 101, 05508-090, São Paulo, SP, Brazil
| | - Antonio C Marques
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, Rua Matao, Trav. 14, 101, 05508-090, São Paulo, SP, Brazil.,Centro de Biologia Marinha, Universidade de São Paulo, Rodovia Manoel Hypólito do Rego, km. 131,5, 11600-000, São Sebastião, Brazil
| | - André C Morandini
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, Rua Matao, Trav. 14, 101, 05508-090, São Paulo, SP, Brazil
| | - Daslav Hranueli
- Section for Bioinformatics, Department of Biochemical Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000, Zagreb, Croatia
| | - Antonio Starcevic
- Section for Bioinformatics, Department of Biochemical Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000, Zagreb, Croatia
| | - Malcolm Ward
- Proteomics Facility, Institute of Psychiatry, Psychology & Neuroscience, King's College London, 16 De Crespigny Park, London, SE5 8AF, UK
| | - Paul F Long
- Institute of Pharmaceutical Science, King's College London, 150 Stamford Street, London, SE1 9NH, UK. .,Department of Chemistry, King's College London, Strand, London, WC2R 2LS, UK. .,Brazil Institute, King's College London, Strand, London, WC2R 2LS, UK. .,Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Av. Prof. Lineu Prestes, 580, B16, 05508-000, São Paulo, SP, Brazil.
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280
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Beligni MV, Bagnato C, Prados MB, Bondino H, Laxalt AM, Munnik T, Ten Have A. The diversity of algal phospholipase D homologs revealed by biocomputational analysis. JOURNAL OF PHYCOLOGY 2015; 51:943-962. [PMID: 26986890 DOI: 10.1111/jpy.12334] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 07/09/2015] [Indexed: 06/05/2023]
Abstract
Phospholipase D (PLD) participates in the formation of phosphatidic acid, a precursor in glycerolipid biosynthesis and a second messenger. PLDs are part of a superfamily of proteins that hydrolyze phosphodiesters and share a catalytic motif, HxKxxxxD, and hence a mechanism of action. Although HKD-PLDs have been thoroughly characterized in plants, animals and bacteria, very little is known about these enzymes in algae. To fill this gap in knowledge, we performed a biocomputational analysis by means of HMMER iterative profiling, using most eukaryotic algae genomes available. Phylogenetic analysis revealed that algae exhibit very few eukaryotic-type PLDs but possess, instead, many bacteria-like PLDs. Among algae eukaryotic-type PLDs, we identified C2-PLDs and PXPH-like PLDs. In addition, the dinoflagellate Alexandrium tamarense features several proteins phylogenetically related to oomycete PLDs. Our phylogenetic analysis also showed that algae bacteria-like PLDs (proteins with putative PLD activity) fall into five clades, three of which are novel lineages in eukaryotes, composed almost entirely of algae. Specifically, Clade II is almost exclusive to diatoms, whereas Clade I and IV are mainly represented by proteins from prasinophytes. The other two clades are composed of mitochondrial PLDs (Clade V or Mito-PLDs), previously found in mammals, and a subfamily of potentially secreted proteins (Clade III or SP-PLDs), which includes a homolog formerly characterized in rice. In addition, our phylogenetic analysis shows that algae have non-PLD members within the bacteria-like HKD superfamily with putative cardiolipin synthase and phosphatidylserine/phosphatidylglycerophosphate synthase activities. Altogether, our results show that eukaryotic algae possess a moderate number of PLDs that belong to very diverse phylogenetic groups.
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Affiliation(s)
- María Verónica Beligni
- Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, CC 1245, Mar del Plata, 7600, Argentina
| | - Carolina Bagnato
- Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Río Negro, Mitre 630. S. C. de Bariloche 8400, Río Negro, Argentina
| | - María Belén Prados
- Instituto de Energía y Desarrollo Sustentable - Comisión Nacional de Energía Atómica, Centro Atómico Bariloche, Av. Bustillo 9500, S. C. de Bariloche 8400, Río Negro, Argentina
| | - Hernán Bondino
- Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, CC 1245, Mar del Plata, 7600, Argentina
| | - Ana María Laxalt
- Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, CC 1245, Mar del Plata, 7600, Argentina
| | - Teun Munnik
- Department of Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, Amsterdam, NL-1098 XH, the Netherlands
| | - Arjen Ten Have
- Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, CC 1245, Mar del Plata, 7600, Argentina
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281
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Shikina S, Chiu YL, Lee YH, Chang CF. From Somatic Cells to Oocytes: A Novel Yolk Protein Produced by Ovarian Somatic Cells in a Stony Coral, Euphyllia ancora1. Biol Reprod 2015; 93:57. [DOI: 10.1095/biolreprod.115.129643] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 07/07/2015] [Indexed: 11/01/2022] Open
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282
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Wang DZ, Zhang SF, Zhang Y, Lin L. Paralytic shellfish toxin biosynthesis in cyanobacteria and dinoflagellates: A molecular overview. J Proteomics 2015; 135:132-140. [PMID: 26316331 DOI: 10.1016/j.jprot.2015.08.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 07/28/2015] [Accepted: 08/14/2015] [Indexed: 12/22/2022]
Abstract
UNLABELLED Paralytic shellfish toxins (PSTs) are a group of water soluble neurotoxic alkaloids produced by two different kingdoms of life, prokaryotic cyanobacteria and eukaryotic dinoflagellates. Owing to the wide distribution of these organisms, these toxic secondary metabolites account for paralytic shellfish poisonings around the world. On the other hand, their specific binding to voltage-gated sodium channels makes these toxins potentially useful in pharmacological and toxicological applications. Much effort has been devoted to the biosynthetic mechanism of PSTs, and gene clusters encoding 26 proteins involved in PST biosynthesis have been unveiled in several cyanobacterial species. Functional analysis of toxin genes indicates that PST biosynthesis in cyanobacteria is a complex process including biosynthesis, regulation, modification and export. However, less is known about the toxin biosynthesis in dinoflagellates owing to our poor understanding of the massive genome and unique chromosomal characteristics [1]. So far, few genes involved in PST biosynthesis have been identified from dinoflagellates. Moreover, the proteins involved in PST production are far from being totally explored. Thus, the origin and evolution of PST biosynthesis in these two kingdoms are still controversial. In this review, we summarize the recent progress on the characterization of genes and proteins involved in PST biosynthesis in cyanobacteria and dinoflagellates, and discuss the standing evolutionary hypotheses concerning the origin of toxin biosynthesis as well as future perspectives in PST biosynthesis. SCIENTIFIC QUESTION Paralytic shellfish toxins (PSTs) are a group of potent neurotoxins which specifically block voltage-gated sodium channels in excitable cells and result in paralytic shellfish poisonings (PSPs) around the world. Two different kingdoms of life, cyanobacteria and dinoflagellates are able to produce PSTs. However, in contrast with cyanobacteria, our understanding of PST biosynthesis in dinoflagellates is extremely limited owing to their unique features. The origin and evolution of PST biosynthesis in these two kingdoms are still controversial. TECHNICAL SIGNIFICANCE High-throughput omics technologies, such as genomics, transcriptomics and proteomics provide powerful tools for the study of PST biosynthesis in cyanobacteria and dinoflagellates, and have shown their powerful potential with regard to revealing genes and proteins involved in PST biosynthesis in two kingdoms. SCIENTIFIC SIGNIFICANCE This review summarizes the recent progress in PST biosynthesis in cyanobacteria and dinoflagellates with focusing on the novel insights from omics technologies, and discusses the evolutionary relationship of toxin biosynthesis genes between these two kingdoms.
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Affiliation(s)
- Da-Zhi Wang
- State Key Laboratory of Marine Environmental Science/College of the Environment and Ecology, Xiamen University, Xiamen 361005, China.
| | - Shu-Fei Zhang
- State Key Laboratory of Marine Environmental Science/College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
| | - Yong Zhang
- State Key Laboratory of Marine Environmental Science/College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
| | - Lin Lin
- State Key Laboratory of Marine Environmental Science/College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
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283
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Lin X, Wang L, Shi X, Lin S. Rapidly diverging evolution of an atypical alkaline phosphatase (PhoA(aty)) in marine phytoplankton: insights from dinoflagellate alkaline phosphatases. Front Microbiol 2015; 6:868. [PMID: 26379645 PMCID: PMC4548154 DOI: 10.3389/fmicb.2015.00868] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 08/10/2015] [Indexed: 11/13/2022] Open
Abstract
Alkaline phosphatase (AP) is a key enzyme that enables marine phytoplankton to scavenge phosphorus (P) from dissolved organic phosphorus (DOP) when inorganic phosphate is scarce in the ocean. Yet how the AP gene has evolved in phytoplankton, particularly dinoflagellates, is poorly understood. We sequenced full-length AP genes and corresponding complementary DNA (cDNA) from 15 strains (10 species), representing four classes of the core dinoflagellate lineage, Gymnodiniales, Prorocentrales, Suessiales, and Gonyaulacales. Dinoflagellate AP gene sequences exhibited high variability, containing variable introns, pseudogenes, single nucleotide polymorphisms and consequent variations in amino acid sequence, indicative of gene duplication events and consistent with the “birth-and-death” model of gene evolution. Further sequence comparison showed that dinoflagellate APs likely belong to an atypical type AP (PhoAaty), which shares conserved motifs with counterparts in marine bacteria, cyanobacteria, green algae, haptophytes, and stramenopiles. Phylogenetic analysis suggested that PhoAaty probably originated from an ancestral gene in bacteria and evolved divergently in marine phytoplankton. Because variations in AP amino acid sequences may lead to differential subcellular localization and potentially different metal ion requirements, the multiple types of APs in algae may have resulted from selection for diversifying strategies to utilize DOP in the P variable marine environment.
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Affiliation(s)
- Xin Lin
- State Key Laboratory of Marine Environmental Science, Xiamen University Xiamen, China
| | - Lu Wang
- State Key Laboratory of Marine Environmental Science, Xiamen University Xiamen, China
| | - Xinguo Shi
- State Key Laboratory of Marine Environmental Science, Xiamen University Xiamen, China
| | - Senjie Lin
- State Key Laboratory of Marine Environmental Science, Xiamen University Xiamen, China ; Department of Marine Sciences, University of Connecticut Groton, CT, USA
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284
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Dorrell RG, Howe CJ. Integration of plastids with their hosts: Lessons learned from dinoflagellates. Proc Natl Acad Sci U S A 2015; 112:10247-54. [PMID: 25995366 PMCID: PMC4547248 DOI: 10.1073/pnas.1421380112] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
After their endosymbiotic acquisition, plastids become intimately connected with the biology of their host. For example, genes essential for plastid function may be relocated from the genomes of plastids to the host nucleus, and pathways may evolve within the host to support the plastid. In this review, we consider the different degrees of integration observed in dinoflagellates and their associated plastids, which have been acquired through multiple different endosymbiotic events. Most dinoflagellate species possess plastids that contain the pigment peridinin and show extreme reduction and integration with the host biology. In some species, these plastids have been replaced through serial endosymbiosis with plastids derived from a different phylogenetic derivation, of which some have become intimately connected with the biology of the host whereas others have not. We discuss in particular the evolution of the fucoxanthin-containing dinoflagellates, which have adapted pathways retained from the ancestral peridinin plastid symbiosis for transcript processing in their current, serially acquired plastids. Finally, we consider why such a diversity of different degrees of integration between host and plastid is observed in different dinoflagellates and how dinoflagellates may thus inform our broader understanding of plastid evolution and function.
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Affiliation(s)
- Richard G Dorrell
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom; School of Biology, École Normale Superieure, Paris 75005, France
| | - Christopher J Howe
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom
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285
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Burns JA, Paasch A, Narechania A, Kim E. Comparative Genomics of a Bacterivorous Green Alga Reveals Evolutionary Causalities and Consequences of Phago-Mixotrophic Mode of Nutrition. Genome Biol Evol 2015. [PMID: 26224703 PMCID: PMC5741210 DOI: 10.1093/gbe/evv144] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Cymbomonas tetramitiformis—a marine prasinophyte—is one of only a few green algae that still retain an ancestral particulate-feeding mechanism while harvesting energy through photosynthesis. The genome of the alga is estimated to be 850 Mb–1.2 Gb in size—the bulk of which is filled with repetitive sequences—and is annotated with 37,366 protein-coding gene models. A number of unusual metabolic pathways (for the Chloroplastida) are predicted for C. tetramitiformis, including pathways for Lipid-A and peptidoglycan metabolism. Comparative analyses of the predicted peptides of C. tetramitiformis to sets of other eukaryotes revealed that nonphagocytes are depleted in a number of genes, a proportion of which have known function in feeding. In addition, our analysis suggests that obligatory phagotrophy is associated with the loss of genes that function in biosynthesis of small molecules (e.g., amino acids). Further, C. tetramitiformis and at least one other phago-mixotrophic alga are thus unique, compared with obligatory heterotrophs and nonphagocytes, in that both feeding and small molecule synthesis-related genes are retained in their genomes. These results suggest that early, ancestral host eukaryotes that gave rise to phototrophs had the capacity to assimilate building block molecules from inorganic substances (i.e., prototrophy). The loss of biosynthesis genes, thus, may at least partially explain the apparent lack of instances of permanent incorporation of photosynthetic endosymbionts in later-divergent, auxotrophic eukaryotic lineages, such as metazoans and ciliates.
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Affiliation(s)
- John A Burns
- Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, NY
| | - Amber Paasch
- Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, NY
| | - Apurva Narechania
- Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, NY
| | - Eunsoo Kim
- Sackler Institute for Comparative Genomics and Division of Invertebrate Zoology, American Museum of Natural History, New York, NY
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Shoguchi E, Shinzato C, Hisata K, Satoh N, Mungpakdee S. The Large Mitochondrial Genome of Symbiodinium minutum Reveals Conserved Noncoding Sequences between Dinoflagellates and Apicomplexans. Genome Biol Evol 2015. [PMID: 26199191 PMCID: PMC4558855 DOI: 10.1093/gbe/evv137] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Even though mitochondrial genomes, which characterize eukaryotic cells, were first discovered more than 50 years ago, mitochondrial genomics remains an important topic in molecular biology and genome sciences. The Phylum Alveolata comprises three major groups (ciliates, apicomplexans, and dinoflagellates), the mitochondrial genomes of which have diverged widely. Even though the gene content of dinoflagellate mitochondrial genomes is reportedly comparable to that of apicomplexans, the highly fragmented and rearranged genome structures of dinoflagellates have frustrated whole genomic analysis. Consequently, noncoding sequences and gene arrangements of dinoflagellate mitochondrial genomes have not been well characterized. Here we report that the continuous assembled genome (∼326 kb) of the dinoflagellate, Symbiodinium minutum, is AT-rich (∼64.3%) and that it contains three protein-coding genes. Based upon in silico analysis, the remaining 99% of the genome comprises transcriptomic noncoding sequences. RNA edited sites and unique, possible start and stop codons clarify conserved regions among dinoflagellates. Our massive transcriptome analysis shows that almost all regions of the genome are transcribed, including 27 possible fragmented ribosomal RNA genes and 12 uncharacterized small RNAs that are similar to mitochondrial RNA genes of the malarial parasite, Plasmodium falciparum. Gene map comparisons show that gene order is only slightly conserved between S. minutum and P. falciparum. However, small RNAs and intergenic sequences share sequence similarities with P. falciparum, suggesting that the function of noncoding sequences has been preserved despite development of very different genome structures.
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Affiliation(s)
- Eiichi Shoguchi
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Chuya Shinzato
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Kanako Hisata
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Nori Satoh
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Sutada Mungpakdee
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
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Woo YH, Ansari H, Otto TD, Klinger CM, Kolisko M, Michálek J, Saxena A, Shanmugam D, Tayyrov A, Veluchamy A, Ali S, Bernal A, del Campo J, Cihlář J, Flegontov P, Gornik SG, Hajdušková E, Horák A, Janouškovec J, Katris NJ, Mast FD, Miranda-Saavedra D, Mourier T, Naeem R, Nair M, Panigrahi AK, Rawlings ND, Padron-Regalado E, Ramaprasad A, Samad N, Tomčala A, Wilkes J, Neafsey DE, Doerig C, Bowler C, Keeling PJ, Roos DS, Dacks JB, Templeton TJ, Waller RF, Lukeš J, Oborník M, Pain A. Chromerid genomes reveal the evolutionary path from photosynthetic algae to obligate intracellular parasites. eLife 2015; 4:e06974. [PMID: 26175406 PMCID: PMC4501334 DOI: 10.7554/elife.06974] [Citation(s) in RCA: 140] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 06/16/2015] [Indexed: 12/18/2022] Open
Abstract
The eukaryotic phylum Apicomplexa encompasses thousands of obligate intracellular parasites of humans and animals with immense socio-economic and health impacts. We sequenced nuclear genomes of Chromera velia and Vitrella brassicaformis, free-living non-parasitic photosynthetic algae closely related to apicomplexans. Proteins from key metabolic pathways and from the endomembrane trafficking systems associated with a free-living lifestyle have been progressively and non-randomly lost during adaptation to parasitism. The free-living ancestor contained a broad repertoire of genes many of which were repurposed for parasitic processes, such as extracellular proteins, components of a motility apparatus, and DNA- and RNA-binding protein families. Based on transcriptome analyses across 36 environmental conditions, Chromera orthologs of apicomplexan invasion-related motility genes were co-regulated with genes encoding the flagellar apparatus, supporting the functional contribution of flagella to the evolution of invasion machinery. This study provides insights into how obligate parasites with diverse life strategies arose from a once free-living phototrophic marine alga. DOI:http://dx.doi.org/10.7554/eLife.06974.001 Single-celled parasites cause many severe diseases in humans and animals. The apicomplexans form probably the most successful group of these parasites and include the parasites that cause malaria. Apicomplexans infect a broad range of hosts, including humans, reptiles, birds, and insects, and often have complicated life cycles. For example, the malaria-causing parasites spread by moving from humans to female mosquitoes and then back to humans. Despite significant differences amongst apicomplexans, these single-celled parasites also share a number of features that are not seen in other living species. How and when these features arose remains unclear. It is known from previous work that apicomplexans are closely related to single-celled algae. But unlike apicomplexans, which depend on a host animal to survive, these algae live freely in their environment, often in close association with corals. Woo et al. have now sequenced the genomes of two photosynthetic algae that are thought to be close living relatives of the apicomplexans. These genomes were then compared to each other and to the genomes of other algae and apicomplexans. These comparisons reconfirmed that the two algae that were studied were close relatives of the apicomplexans. Further analyses suggested that thousands of genes were lost as an ancient free-living algae evolved into the apicomplexan ancestor, and further losses occurred as these early parasites evolved into modern species. The lost genes were typically those that are important for free-living organisms, but are either a hindrance to, or not needed in, a parasitic lifestyle. Some of the ancestor's genes, especially those that coded for the building blocks of flagella (structures which free-living algae use to move around), were repurposed in ways that helped the apicomplexans to invade their hosts. Understanding this repurposing process in greater detail will help to identify key molecules in these deadly parasites that could be targeted by drug treatments. It will also offer answers to one of the most fascinating questions in evolutionary biology: how parasites have evolved from free-living organisms. DOI:http://dx.doi.org/10.7554/eLife.06974.002
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Affiliation(s)
- Yong H Woo
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Hifzur Ansari
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Thomas D Otto
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, United Kingdom
| | | | - Martin Kolisko
- Canadian Institute for Advanced Research, Department of Botany, University of British Columbia, Vancouver, Canada
| | - Jan Michálek
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Alka Saxena
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | | | - Annageldi Tayyrov
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Alaguraj Veluchamy
- Ecology and Evolutionary Biology Section, Institut de Biologie de l'Ecole Normale Supérieure, CNRS UMR8197 INSERM U1024, Paris, France
| | - Shahjahan Ali
- Bioscience Core Laboratory, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Axel Bernal
- Department of Biology, University of Pennsylvania, Philadelphia, United States
| | - Javier del Campo
- Canadian Institute for Advanced Research, Department of Botany, University of British Columbia, Vancouver, Canada
| | - Jaromír Cihlář
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Pavel Flegontov
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | | | - Eva Hajdušková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Aleš Horák
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jan Janouškovec
- Canadian Institute for Advanced Research, Department of Botany, University of British Columbia, Vancouver, Canada
| | | | - Fred D Mast
- Seattle Biomedical Research Institute, Seattle, United States
| | - Diego Miranda-Saavedra
- Centro de Biología Molecular Severo Ochoa, CSIC/Universidad Autónoma de Madrid, Madrid, Spain
| | - Tobias Mourier
- Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark
| | - Raeece Naeem
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Mridul Nair
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Aswini K Panigrahi
- Bioscience Core Laboratory, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Neil D Rawlings
- European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Eriko Padron-Regalado
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Abhinay Ramaprasad
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Nadira Samad
- School of Botany, University of Melbourne, Parkville, Australia
| | - Aleš Tomčala
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jon Wilkes
- Wellcome Trust Centre For Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Daniel E Neafsey
- Broad Genome Sequencing and Analysis Program, Broad Institute of MIT and Harvard, Cambridge, United States
| | - Christian Doerig
- Department of Microbiology, Monash University, Clayton, Australia
| | - Chris Bowler
- Ecology and Evolutionary Biology Section, Institut de Biologie de l'Ecole Normale Supérieure, CNRS UMR8197 INSERM U1024, Paris, France
| | - Patrick J Keeling
- Canadian Institute for Advanced Research, Department of Botany, University of British Columbia, Vancouver, Canada
| | - David S Roos
- Department of Biology, University of Pennsylvania, Philadelphia, United States
| | - Joel B Dacks
- Department of Cell Biology, University of Alberta, Edmonton, Canada
| | - Thomas J Templeton
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, United States
| | - Ross F Waller
- School of Botany, University of Melbourne, Parkville, Australia
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Miroslav Oborník
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Arnab Pain
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
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288
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Heterologous DNA Uptake in Cultured Symbiodinium spp. Aided by Agrobacterium tumefaciens. PLoS One 2015; 10:e0132693. [PMID: 26167858 PMCID: PMC4500500 DOI: 10.1371/journal.pone.0132693] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 06/17/2015] [Indexed: 11/19/2022] Open
Abstract
Plant-targeted pCB302 plasmids containing sequences encoding gfp fusions with a microtubule-binding domain; gfp with the fimbrin actin-binding domain 2; and gfp with AtRACK1C from Arabidopsis thaliana, all harbored in Agrobacterium tumefaciens, were used to assay heterologous expression on three different clades of the photosynthetic dinoflagellate, Symbiodinium. Accessibility to the resistant cell wall and through the plasma membrane of these dinoflagellates was gained after brief but vigorous shaking in the presence of glass beads and polyethylene glycol. A resistance gene to the herbicide Basta allowed appropriate selection of the cells expressing the hybrid proteins, which showed a characteristic green fluorescence, although they appeared to lose their photosynthetic pigments and did not further divide. Cell GFP expression frequency measured as green fluorescence emission yielded 839 per every 106 cells for Symbiodinium kawagutii, followed by 640 and 460 per every 106 cells for Symbiodinium microadriaticum and Symbiodinium sp. Mf11, respectively. Genomic PCR with specific primers amplified the AtRACK1C and gfp sequences after selection in all clades, thus revealing their presence in the cells. RT-PCR from RNA of S. kawagutii co-incubated with A. tumefaciens harboring each of the three vectors with their respective constructs, amplified products corresponding to the heterologous gfp sequence while no products were obtained from three distinct negative controls. The reported procedure shows that mild abrasion followed by co-incubation with A. tumefaciens harboring heterologous plasmids with CaMV35S and nos promoters can lead to expression of the encoded proteins into the Symbiodinium cells in culture. Despite the obvious drawbacks of the procedure, this is an important first step towards a stable transformation of Symbiodinium.
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289
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Mendez GS, Delwiche CF, Apt KE, Lippmeier JC. Dinoflagellate Gene Structure and Intron Splice Sites in a Genomic Tandem Array. J Eukaryot Microbiol 2015; 62:679-87. [PMID: 25963315 PMCID: PMC5032977 DOI: 10.1111/jeu.12230] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 04/06/2015] [Accepted: 04/22/2015] [Indexed: 11/24/2022]
Abstract
Dinoflagellates are one of the last major lineages of eukaryotes for which little is known about genome structure and organization. We report here the sequence and gene structure of a clone isolated from a cosmid library which, to our knowledge, represents the largest contiguously sequenced, dinoflagellate genomic, tandem gene array. These data, combined with information from a large transcriptomic library, allowed a high level of confidence of every base pair call. This degree of confidence is not possible with PCR‐based contigs. The sequence contains an intron‐rich set of five highly expressed gene repeats arranged in tandem. One of the tandem repeat gene members contains an intron 26,372 bp long. This study characterizes a splice site consensus sequence for dinoflagellate introns. Two to nine base pairs around the 3′ splice site are repeated by an identical two to nine base pairs around the 5′ splice site. The 5′ and 3′ splice sites are in the same locations within each repeat so that the repeat is found only once in the mature mRNA. This identically repeated intron boundary sequence might be useful in gene modeling and annotation of genomes.
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Affiliation(s)
- Gregory S Mendez
- Department of Cell Biology and Molecular Genetics, University of Maryland College Park, College Park, Maryland, 20742-5815
| | - Charles F Delwiche
- Department of Cell Biology and Molecular Genetics, University of Maryland College Park, College Park, Maryland, 20742-5815.,Maryland Agricultural Experiment Station, College Park, Maryland, 20742
| | - Kirk E Apt
- DSM Nutritional Products, 6480 Dobbin Rd, Columbia, Maryland, 21045
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290
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Hehenberger E, Imanian B, Burki F, Keeling PJ. Evidence for the retention of two evolutionary distinct plastids in dinoflagellates with diatom endosymbionts. Genome Biol Evol 2015; 6:2321-34. [PMID: 25172904 PMCID: PMC4217693 DOI: 10.1093/gbe/evu182] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Dinoflagellates harboring diatom endosymbionts (termed “dinotoms”) have undergone a process often referred to as “tertiary endosymbiosis”—the uptake of algae containing secondary plastids and integration of those plastids into the new host. In contrast to other tertiary plastids, and most secondary plastids, the endosymbiont of dinotoms is distinctly less reduced, retaining a number of cellular features, such as their nucleus and mitochondria and others, in addition to their plastid. This has resulted in redundancy between host and endosymbiont, at least between some mitochondrial and cytosolic metabolism, where this has been investigated. The question of plastidial redundancy is particularly interesting as the fate of the host dinoflagellate plastid is unclear. The host cytosol possesses an eyespot that has been postulated to be a remnant of the ancestral peridinin plastid, but this has not been tested, nor has its possible retention of plastid functions. To investigate this possibility, we searched for plastid-associated pathways and functions in transcriptomic data sets from three dinotom species. We show that the dinoflagellate host has indeed retained genes for plastid-associated pathways and that these genes encode targeting peptides similar to those of other dinoflagellate plastid-targeted proteins. Moreover, we also identified one gene encoding an essential component of the dinoflagellate plastid protein import machinery, altogether suggesting the presence of a functioning plastid import system in the host, and by extension a relict plastid. The presence of the same plastid-associated pathways in the endosymbiont also extends the known functional redundancy in dinotoms, further confirming the unusual state of plastid integration in this group of dinoflagellates.
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Affiliation(s)
- Elisabeth Hehenberger
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, British Columbia, Canada
| | - Behzad Imanian
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, British Columbia, Canada
| | - Fabien Burki
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, British Columbia, Canada
| | - Patrick J Keeling
- Department of Botany, Canadian Institute for Advanced Research, University of British Columbia, Vancouver, British Columbia, Canada
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291
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Polyketide synthesis genes associated with toxin production in two species of Gambierdiscus (Dinophyceae). BMC Genomics 2015; 16:410. [PMID: 26016672 PMCID: PMC4445524 DOI: 10.1186/s12864-015-1625-y] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 05/07/2015] [Indexed: 11/10/2022] Open
Abstract
Background Marine microbial protists, in particular, dinoflagellates, produce polyketide toxins with ecosystem-wide and human health impacts. Species of Gambierdiscus produce the polyether ladder compounds ciguatoxins and maitotoxins, which can lead to ciguatera fish poisoning, a serious human illness associated with reef fish consumption. Genes associated with the biosynthesis of polyether ladder compounds are yet to be elucidated, however, stable isotope feeding studies of such compounds consistently support their polyketide origin indicating that polyketide synthases are involved in their biosynthesis. Results Here, we report the toxicity, genome size, gene content and transcriptome of Gambierdiscus australes and G. belizeanus. G. australes produced maitotoxin-1 and maitotoxin-3, while G. belizeanus produced maitotoxin-3, for which cell extracts were toxic to mice by IP injection (LD50 = 3.8 mg kg-1). The gene catalogues comprised 83,353 and 84,870 unique contigs, with genome sizes of 32.5 ± 3.7 Gbp and 35 ± 0.88 Gbp, respectively, and are amongst the most comprehensive yet reported from a dinoflagellate. We found three hundred and six genes involved in polyketide biosynthesis, including one hundred and ninty-two ketoacyl synthase transcripts, which formed five unique phylogenetic clusters. Conclusions Two clusters were unique to these maitotoxin-producing dinoflagellate species, suggesting that they may be associated with maitotoxin biosynthesis. This work represents a significant step forward in our understanding of the genetic basis of polyketide production in dinoflagellates, in particular, species responsible for ciguatera fish poisoning. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1625-y) contains supplementary material, which is available to authorized users.
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292
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Stüken A, Riobó P, Franco J, Jakobsen KS, Guillou L, Figueroa RI. Paralytic shellfish toxin content is related to genomic sxtA4 copy number in Alexandrium minutum strains. Front Microbiol 2015; 6:404. [PMID: 25983733 PMCID: PMC4416454 DOI: 10.3389/fmicb.2015.00404] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 04/17/2015] [Indexed: 11/27/2022] Open
Abstract
Dinoflagellates are microscopic aquatic eukaryotes with huge genomes and an unusual cell regulation. For example, most genes are present in numerous copies and all copies seem to be obligatorily transcribed. The consequence of the gene copy number (CPN) for final protein synthesis is, however, not clear. One such gene is sxtA, the starting gene of paralytic shellfish toxin (PST) synthesis. PSTs are small neurotoxic compounds that can accumulate in the food chain and cause serious poisoning incidences when ingested. They are produced by dinoflagellates of the genera Alexandrium, Gymnodium, and Pyrodinium. Here we investigated if the genomic CPN of sxtA4 is related to PST content in Alexandrium minutum cells. SxtA4 is the 4th domain of the sxtA gene and its presence is essential for PST synthesis in dinoflagellates. We used PST and genome size measurements as well as quantitative PCR to analyze sxtA4 CPN and toxin content in 15 A. minutum strains. Our results show a strong positive correlation between the sxtA4 CPN and the total amount of PST produced in actively growing A. minutum cells. This correlation was independent of the toxin profile produced, as long as the strain contained the genomic domains sxtA1 and sxtA4.
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Affiliation(s)
- Anke Stüken
- Department of Biosciences, University of Oslo Oslo, Norway
| | - Pilar Riobó
- U.A. Microalgas Nocivas (Consejo Superior de Investigaciones Científicas - Instituto Español de Oceanografía), Instituto de Investigaciones Marinas Vigo, Spain
| | - José Franco
- U.A. Microalgas Nocivas (Consejo Superior de Investigaciones Científicas - Instituto Español de Oceanografía), Instituto de Investigaciones Marinas Vigo, Spain
| | - Kjetill S Jakobsen
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo Oslo, Norway
| | - Laure Guillou
- Laboratoire Adaptation et Diversité en Milieu Marin, CNRS, UMR 7144 Roscoff, France ; Sorbonne Universités - Université Pierre et Marie Curie, UMR 7144 Roscoff, France
| | - Rosa I Figueroa
- Aquatic Ecology, Lund University Lund, Sweden ; U.A. Microalgas Nocivas (Consejo Superior de Investigaciones Científicas - Instituto Español de Oceanografía), Instituto Español de Oceanografía Vigo, Spain
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293
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Abstract
The endosymbiotic origin of plastids from cyanobacteria was a landmark event in the history of eukaryotic life. Subsequent to the evolution of primary plastids, photosynthesis spread from red and green algae to unrelated eukaryotes by secondary and tertiary endosymbiosis. Although the movement of cyanobacterial genes from endosymbiont to host is well studied, less is known about the migration of eukaryotic genes from one nucleus to the other in the context of serial endosymbiosis. Here I explore the magnitude and potential impact of nucleus-to-nucleus endosymbiotic gene transfer in the evolution of complex algae, and the extent to which such transfers compromise our ability to infer the deep structure of the eukaryotic tree of life. In addition to endosymbiotic gene transfer, horizontal gene transfer events occurring before, during, and after endosymbioses further confound our efforts to reconstruct the ancient mergers that forged multiple lines of photosynthetic microbial eukaryotes.
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294
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Pinzón JH, Kamel B, Burge CA, Harvell CD, Medina M, Weil E, Mydlarz LD. Whole transcriptome analysis reveals changes in expression of immune-related genes during and after bleaching in a reef-building coral. ROYAL SOCIETY OPEN SCIENCE 2015; 2:140214. [PMID: 26064625 PMCID: PMC4448857 DOI: 10.1098/rsos.140214] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 03/04/2015] [Indexed: 05/18/2023]
Abstract
Climate change is negatively affecting the stability of natural ecosystems, especially coral reefs. The dissociation of the symbiosis between reef-building corals and their algal symbiont, or coral bleaching, has been linked to increased sea surface temperatures. Coral bleaching has significant impacts on corals, including an increase in disease outbreaks that can permanently change the entire reef ecosystem. Yet, little is known about the impacts of coral bleaching on the coral immune system. In this study, whole transcriptome analysis of the coral holobiont and each of the associate components (i.e. coral host, algal symbiont and other associated microorganisms) was used to determine changes in gene expression in corals affected by a natural bleaching event as well as during the recovery phase. The main findings include evidence that the coral holobiont and the coral host have different responses to bleaching, and the host immune system appears suppressed even a year after a bleaching event. These results support the hypothesis that coral bleaching changes the expression of innate immune genes of corals, and these effects can last even after recovery of symbiont populations. Research on the role of immunity on coral's resistance to stressors can help make informed predictions on the future of corals and coral reefs.
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Affiliation(s)
- Jorge H. Pinzón
- Department of Biology, University of Texas Arlington, Arlington, TX 76016, USA
- Author for correspondence: Jorge H. Pinzón e-mail:
| | - Bishoy Kamel
- Department of Biology, The Pennsylvania State University, State College, PA 16802, USA
| | - Colleen A. Burge
- Institute of Marine and Environmental Technology, University of Maryland Baltimore County Columbus Center, 701 East Pratt Street, Baltimore, MD 21202, USA
| | - C. Drew Harvell
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - Mónica Medina
- Department of Biology, The Pennsylvania State University, State College, PA 16802, USA
| | - Ernesto Weil
- Department of Marine Sciences, University of Puerto Rico—Mayagüez, La Parguera, PR 00865, USA
| | - Laura D. Mydlarz
- Department of Biology, University of Texas Arlington, Arlington, TX 76016, USA
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Xiang T, Nelson W, Rodriguez J, Tolleter D, Grossman AR. Symbiodinium transcriptome and global responses of cells to immediate changes in light intensity when grown under autotrophic or mixotrophic conditions. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 82:67-80. [PMID: 25664570 DOI: 10.1111/tpj.12789] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 01/26/2015] [Accepted: 02/03/2015] [Indexed: 05/10/2023]
Abstract
Symbiosis between unicellular dinoflagellates (genus Symbiodinium) and their cnidarian hosts (e.g. corals, sea anemones) is the foundation of coral reef ecosystems. Dysfunction of this symbiosis under changing environmental conditions has led to global reef decline. Little information is known about Symbiodinium gene expression and mechanisms by which light impacts host-symbiont associations. To address these issues, we generated a transcriptome from axenic Symbiodinium strain SSB01. Here we report features of the transcriptome, including occurrence and length distribution of spliced leader sequences, the functional landscape of encoded proteins and the impact of light on gene expression. Expression of many Symbiodinium genes appears to be significantly impacted by light. Transcript encoding cryptochrome 2 declined in high light while some transcripts for Regulators of Chromatin Condensation (RCC1) declined in the dark. We also identified a transcript encoding a light harvesting AcpPC protein with homology to Chlamydomonas LHCSR2. The level of this transcript increased in high light autotrophic conditions, suggesting that it is involved in photo-protection and the dissipation of excess absorbed light energy. The most extensive changes in transcript abundances occurred when the algae were transferred from low light to darkness. Interestingly, transcripts encoding several cell adhesion proteins rapidly declined following movement of cultures to the dark, which correlated with a dramatic change in cell surface morphology, likely reflecting the complexity of the extracellular matrix. Thus, light-sensitive cell adhesion proteins may play a role in establishing surface architecture, which may in turn alter interactions between the endosymbiont and its host.
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Affiliation(s)
- Tingting Xiang
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA, 94305, USA
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Cassell RT, Chen W, Thomas S, Liu L, Rein KS. Brevetoxin, the Dinoflagellate Neurotoxin, Localizes to Thylakoid Membranes and Interacts with the Light-Harvesting Complex II (LHCII) of Photosystem II. Chembiochem 2015; 16:1060-7. [DOI: 10.1002/cbic.201402669] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Indexed: 11/11/2022]
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297
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Rosic N, Ling EYS, Chan CKK, Lee HC, Kaniewska P, Edwards D, Dove S, Hoegh-Guldberg O. Unfolding the secrets of coral-algal symbiosis. ISME JOURNAL 2015; 9:844-56. [PMID: 25343511 DOI: 10.1038/ismej.2014.182] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 08/05/2014] [Accepted: 08/25/2014] [Indexed: 11/09/2022]
Abstract
Dinoflagellates from the genus Symbiodinium form a mutualistic symbiotic relationship with reef-building corals. Here we applied massively parallel Illumina sequencing to assess genetic similarity and diversity among four phylogenetically diverse dinoflagellate clades (A, B, C and D) that are commonly associated with corals. We obtained more than 30,000 predicted genes for each Symbiodinium clade, with a majority of the aligned transcripts corresponding to sequence data sets of symbiotic dinoflagellates and <2% of sequences having bacterial or other foreign origin. We report 1053 genes, orthologous among four Symbiodinium clades, that share a high level of sequence identity to known proteins from the SwissProt (SP) database. Approximately 80% of the transcripts aligning to the 1053 SP genes were unique to Symbiodinium species and did not align to other dinoflagellates and unrelated eukaryotic transcriptomes/genomes. Six pathways were common to all four Symbiodinium clades including the phosphatidylinositol signaling system and inositol phosphate metabolism pathways. The list of Symbiodinium transcripts common to all four clades included conserved genes such as heat shock proteins (Hsp70 and Hsp90), calmodulin, actin and tubulin, several ribosomal, photosynthetic and cytochrome genes and chloroplast-based heme-containing cytochrome P450, involved in the biosynthesis of xanthophylls. Antioxidant genes, which are important in stress responses, were also preserved, as were a number of calcium-dependent and calcium/calmodulin-dependent protein kinases that may play a role in the establishment of symbiosis. Our findings disclose new knowledge about the genetic uniqueness of symbiotic dinoflagellates and provide a list of homologous genes important for the foundation of coral-algal symbiosis.
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Affiliation(s)
- Nedeljka Rosic
- School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Edmund Yew Siang Ling
- University of Queensland Centre for Clinical Research, The University of Queensland, Herston, Queensland, Australia
| | - Chon-Kit Kenneth Chan
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Hong Ching Lee
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
| | - Paulina Kaniewska
- 1] School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia [2] Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - David Edwards
- 1] School of Agriculture and Food Sciences, The University of Queensland, St Lucia, Queensland, Australia [2] School of Plant Biology, University of Western Australia, Perth, Western Australia, Australia [3] Australian Centre for Plant Functional Genomics, The University of Queensland, St Lucia, Queensland, Australia
| | - Sophie Dove
- 1] School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia [2] ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St Lucia, Queensland, Australia
| | - Ove Hoegh-Guldberg
- 1] School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia [2] ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St Lucia, Queensland, Australia [3] Global Change Institute and ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St Lucia, Queensland, Australia
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298
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Diversification of the light-harvesting complex gene family via intra- and intergenic duplications in the coral symbiotic alga Symbiodinium. PLoS One 2015; 10:e0119406. [PMID: 25741697 PMCID: PMC4351107 DOI: 10.1371/journal.pone.0119406] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 01/12/2015] [Indexed: 12/22/2022] Open
Abstract
The light-harvesting complex (LHC) is an essential component in light energy capture and transduction to facilitate downstream photosynthetic reactions in plant and algal chloroplasts. The unicellular dinoflagellate alga Symbiodinium is an endosymbiont of cnidarian animals, including corals and sea anemones, and provides carbohydrates generated through photosynthesis to host animals. Although Symbiodinium possesses a unique LHC gene family, called chlorophyll a-chlorophyll c2-peridinin protein complex (acpPC), its genome-level diversity and evolutionary trajectories have not been investigated. Here, we describe a phylogenetic analysis revealing that many of the LHCs are encoded by highly duplicated genes with multi-subunit polyprotein structures in the nuclear genome of Symbiodinium minutum. This analysis provides an extended list of the LHC gene family in a single organism, including 80 loci encoding polyproteins composed of 145 LHC subunits recovered in the phylogenetic tree. In S. minutum, 5 phylogenetic groups of the Lhcf-type gene family, which is exclusively conserved in algae harboring secondary plastids of red algal origin, were identified. Moreover, 5 groups of the Lhcr-type gene family, of which members are known to be associated with PSI in red algal plastids and secondary plastids of red algal origin, were identified. Notably, members classified within a phylogenetic group of the Lhcf-type (group F1) are highly duplicated, which may explain the presence of an unusually large number of LHC genes in this species. Some gene units were homologous to other units within single loci of the polyprotein genes, whereas intergenic homologies between separate loci were conspicuous in other cases, implying that gene unit ‘shuffling’ by gene conversion and/or genome rearrangement might have been a driving force for diversification. These results suggest that vigorous intra- and intergenic gene duplication events have resulted in the genomic framework of photosynthesis in coral symbiont dinoflagellate algae.
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299
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Weston AJ, Dunlap WC, Beltran VH, Starcevic A, Hranueli D, Ward M, Long PF. Proteomics links the redox state to calcium signaling during bleaching of the scleractinian coral Acropora microphthalma on exposure to high solar irradiance and thermal stress. Mol Cell Proteomics 2015; 14:585-95. [PMID: 25561505 PMCID: PMC4349979 DOI: 10.1074/mcp.m114.043125] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 08/08/2014] [Indexed: 11/06/2022] Open
Abstract
Shipboard experiments were each performed over a 2 day period to examine the proteomic response of the symbiotic coral Acropora microphthalma exposed to acute conditions of high temperature/low light or high light/low temperature stress. During these treatments, corals had noticeably bleached. The photosynthetic performance of residual algal endosymbionts was severely impaired but showed signs of recovery in both treatments by the end of the second day. Changes in the coral proteome were determined daily and, using recently available annotated genome sequences, the individual contributions of the coral host and algal endosymbionts could be extracted from these data. Quantitative changes in proteins relevant to redox state and calcium metabolism are presented. Notably, expression of common antioxidant proteins was not detected from the coral host but present in the algal endosymbiont proteome. Possible roles for elevated carbonic anhydrase in the coral host are considered: to restore intracellular pH diminished by loss of photosynthetic activity, to indirectly limit intracellular calcium influx linked with enhanced calmodulin expression to impede late-stage symbiont exocytosis, or to enhance inorganic carbon transport to improve the photosynthetic performance of algal symbionts that remain in hospite. Protein effectors of calcium-dependent exocytosis were present in both symbiotic partners. No caspase-family proteins associated with host cell apoptosis, with exception of the autophagy chaperone HSP70, were detected, suggesting that algal loss and photosynthetic dysfunction under these experimental conditions were not due to host-mediated phytosymbiont destruction. Instead, bleaching occurred by symbiont exocytosis and loss of light-harvesting pigments of algae that remain in hospite. These proteomic data are, therefore, consistent with our premise that coral endosymbionts can mediate their own retention or departure from the coral host, which may manifest as "symbiont shuffling" of Symbiodinium clades in response to environmental stress.
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Affiliation(s)
- Andrew J Weston
- From the ‡King's College London Proteomics Facility, Institute of Psychiatry, London SE5 8AF, UK
| | - Walter C Dunlap
- §Centre for Marine Microbiology and Genetics, Australian Institute of Marine Science, PMB No. 3 Townsville MC, Townsville, Queensland,4810 Australia. ‖Institute of Pharmaceutical Science, Kings College, Strand, London WC2R 2LS, United Kingdom
| | - Victor H Beltran
- §Centre for Marine Microbiology and Genetics, Australian Institute of Marine Science, PMB No. 3 Townsville MC, Townsville, Queensland,4810 Australia. ¶ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville QLD 4811 Australia
| | - Antonio Starcevic
- ‡‡Section for Bioinformatics, Department of Biochemical Engineering, Faculty of Food Technology & Biotechnology, University of Zagreb, Pierottijeva 6, HR-10000 Zagreb, Croatia
| | - Daslav Hranueli
- ‡‡Section for Bioinformatics, Department of Biochemical Engineering, Faculty of Food Technology & Biotechnology, University of Zagreb, Pierottijeva 6, HR-10000 Zagreb, Croatia
| | - Malcolm Ward
- From the ‡King's College London Proteomics Facility, Institute of Psychiatry, London SE5 8AF, UK
| | - Paul F Long
- ‖Institute of Pharmaceutical Science, Kings College, Strand, London WC2R 2LS, United Kingdom, **Department of Chemistry, King's College Strand, London WC2R 2LS, United Kingdom, Franklin-Wilkins Building, Stamford Street, London SE1 9NH, UK
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300
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Mayfield AB, Wang YB, Chen CS, Lin CY, Chen SH. Compartment-specific transcriptomics in a reef-building coral exposed to elevated temperatures. Mol Ecol 2015; 23:5816-30. [PMID: 25354956 PMCID: PMC4265203 DOI: 10.1111/mec.12982] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 10/15/2014] [Accepted: 10/20/2014] [Indexed: 12/27/2022]
Abstract
Although rising ocean temperatures threaten scleractinian corals and the reefs they construct, certain reef corals can acclimate to elevated temperatures to which they are rarely exposed in situ. Specimens of the model Indo-Pacific reef coral Pocillopora damicornis collected from upwelling reefs of Southern Taiwan were previously found to have survived a 36-week exposure to 30°C, a temperature they encounter infrequently and one that can elicit the breakdown of the coral–dinoflagellate (genus Symbiodinium) endosymbiosis in many corals of the Pacific Ocean. To gain insight into the subcellular pathways utilized by both the coral hosts and their mutualistic Symbiodinium populations to acclimate to this temperature, mRNAs from both control (27°C) and high (30°C)-temperature samples were sequenced on an Illumina platform and assembled into a 236 435-contig transcriptome. These P. damicornis specimens were found to be ∼60% anthozoan and 40% microbe (Symbiodinium, other eukaryotic microbes, and bacteria), from an mRNA-perspective. Furthermore, a significantly higher proportion of genes from the Symbiodinium compartment were differentially expressed after two weeks of exposure. Specifically, at elevated temperatures, Symbiodinium populations residing within the coral gastrodermal tissues were more likely to up-regulate the expression of genes encoding proteins involved in metabolism than their coral hosts. Collectively, these transcriptome-scale data suggest that the two members of this endosymbiosis have distinct strategies for acclimating to elevated temperatures that are expected to characterize many of Earth's coral reefs in the coming decades.
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Affiliation(s)
- Anderson B Mayfield
- National Museum of Marine Biology and Aquarium, 2 Houwan Rd., Checheng, Pingtung, 944, Taiwan; Living Oceans Foundation, 8181 Professional Place, Suite 215, Landover, MD, 20785, USA
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