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Yoshioka Y, Chiu YL, Uchida T, Yamashita H, Suzuki G, Shinzato C. Genes possibly related to symbiosis in early life stages of Acropora tenuis inoculated with Symbiodinium microadriaticum. Commun Biol 2023; 6:1027. [PMID: 37853100 PMCID: PMC10584924 DOI: 10.1038/s42003-023-05350-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 09/12/2023] [Indexed: 10/20/2023] Open
Abstract
Due to the ecological importance of mutualism between reef-building corals and symbiotic algae (Family Symbiodiniaceae), various transcriptomic studies on coral-algal symbiosis have been performed; however, molecular mechanisms, especially genes essential to initiate and maintain these symbioses remain unknown. We investigated transcriptomic responses of Acropora tenuis to inoculation with the native algal symbiont, Symbiodinium microadriaticum, during early life stages, and identified possible symbiosis-related genes. Genes involved in immune regulation, protection against oxidative stress, and metabolic interactions between partners are particularly important for symbiosis during Acropora early life stages. In addition, molecular phylogenetic analysis revealed that some possible symbiosis-related genes originated by gene duplication in the Acropora lineage, suggesting that gene duplication may have been the driving force to establish stable mutualism in Acropora, and that symbiotic molecular mechanisms may vary among coral lineages.
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Affiliation(s)
- Yuki Yoshioka
- Atmosphere and Ocean Research Institute (AORI), The University of Tokyo, Kashiwa, Chiba, Japan.
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan.
| | - Yi-Ling Chiu
- Atmosphere and Ocean Research Institute (AORI), The University of Tokyo, Kashiwa, Chiba, Japan
| | - Taiga Uchida
- Atmosphere and Ocean Research Institute (AORI), The University of Tokyo, Kashiwa, Chiba, Japan
| | - Hiroshi Yamashita
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, Ishigaki, Okinawa, Japan
| | - Go Suzuki
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, Ishigaki, Okinawa, Japan
| | - Chuya Shinzato
- Atmosphere and Ocean Research Institute (AORI), The University of Tokyo, Kashiwa, Chiba, Japan.
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2
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Lin S, Guo Y, Huang Z, Tang K, Wang X. Comparative Genomic Analysis of Cold-Water Coral-Derived Sulfitobacter faviae: Insights into Their Habitat Adaptation and Metabolism. Mar Drugs 2023; 21:md21050309. [PMID: 37233503 DOI: 10.3390/md21050309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 05/27/2023] Open
Abstract
Sulfitobacter is one of the major sulfite-oxidizing alphaproteobacterial groups and is often associated with marine algae and corals. Their association with the eukaryotic host cell may have important ecological contexts due to their complex lifestyle and metabolism. However, the role of Sulfitobacter in cold-water corals remains largely unexplored. In this study, we explored the metabolism and mobile genetic elements (MGEs) in two closely related Sulfitobacter faviae strains isolated from cold-water black corals at a depth of ~1000 m by comparative genomic analysis. The two strains shared high sequence similarity in chromosomes, including two megaplasmids and two prophages, while both contained several distinct MGEs, including prophages and megaplasmids. Additionally, several toxin-antitoxin systems and other types of antiphage elements were also identified in both strains, potentially helping Sulfitobacter faviae overcome the threat of diverse lytic phages. Furthermore, the two strains shared similar secondary metabolite biosynthetic gene clusters and genes involved in dimethylsulfoniopropionate (DMSP) degradation pathways. Our results provide insight into the adaptive strategy of Sulfitobacter strains to thrive in ecological niches such as cold-water corals at the genomic level.
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Affiliation(s)
- Shituan Lin
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunxue Guo
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Zixian Huang
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaihao Tang
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Xiaoxue Wang
- Key Laboratory of Tropical Marine Bioresources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
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3
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Hazraty-Kari S, Morita M, Tavakoli-Kolour P, Nakamura T, Harii S. Reactions of juvenile coral to three years of consecutive thermal stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 863:161227. [PMID: 36586691 DOI: 10.1016/j.scitotenv.2022.161227] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 12/06/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023]
Abstract
As global temperatures continue to rise, corals are being exposed to increasing heat stress throughout their early life stages; however, the impact of this phenomenon is poorly understood. We exposed the reef-building coral Acropora tenuis juveniles to ∼26-28 °C (control) and ∼ 31 °C (heat stress) for one week per year over three consecutive years. In the first year of heat stress, >96 % of juveniles survived despite symbiotic algal densities in juvenile corals declining. In comparison, survival rates in the third year of heat stress declined to 50 %. Survival rates under natural conditions after stress also gradually decreased in the stressed groups. The rate in the reduction of survivorship was prominent in the consecutive thermally stressed groups (juveniles stressed twice in two years). Symbiotic algal density and photosynthetic activity (Fv/Fm) also declined in stressed juvenile groups. However, heat stress did not significantly affect the growth of juveniles. In the third year of heat stress, temperature negatively affected the physiology of juveniles in terms of survivorship, brightness (an indicator of bleaching), symbiotic algal density, and photosynthetic efficiency. Stress across consecutive years appeared to cause the survivorship of juvenile corals to decline, with three years of stress contributing to the severe decline of a reef. In conclusion, A. tenuis juveniles are not able to acclimatize to heat stress, with successive heat waves of <7 days in the summer potentially negatively affecting resilience.
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Affiliation(s)
- Sanaz Hazraty-Kari
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan.
| | - Masaya Morita
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | | | - Takashi Nakamura
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan; Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | - Saki Harii
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan.
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4
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Camp EF, Nitschke MR, Clases D, Gonzalez de Vega R, Reich HG, Goyen S, Suggett DJ. Micronutrient content drives elementome variability amongst the Symbiodiniaceae. BMC PLANT BIOLOGY 2022; 22:184. [PMID: 35395710 PMCID: PMC8994382 DOI: 10.1186/s12870-022-03512-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 03/06/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Elements are the basis of life on Earth, whereby organisms are essentially evolved chemical substances that dynamically interact with each other and their environment. Determining species elemental quotas (their elementome) is a key indicator for their success across environments with different resource availabilities. Elementomes remain undescribed for functionally diverse dinoflagellates within the family Symbiodiniaceae that includes coral endosymbionts. We used dry combustion and ICP-MS to assess whether Symbiodiniaceae (ten isolates spanning five genera Breviolum, Cladocopium, Durusdinium, Effrenium, Symbiodinium) maintained under long-term nutrient replete conditions have unique elementomes (six key macronutrients and nine micronutrients) that would reflect evolutionarily conserved preferential elemental acquisition. For three isolates we assessed how elevated temperature impacted their elementomes. Further, we tested whether Symbiodiniaceae conform to common stoichiometric hypotheses (e.g., the growth rate hypothesis) documented in other marine algae. This study considers whether Symbiodiniaceae isolates possess unique elementomes reflective of their natural ecologies, evolutionary histories, and resistance to environmental change. RESULTS Symbiodiniaceae isolates maintained under long-term luxury uptake conditions, all exhibited highly divergent elementomes from one another, driven primarily by differential content of micronutrients. All N:P and C:P ratios were below the Redfield ratio values, whereas C:N was close to the Redfield value. Elevated temperature resulted in a more homogenised elementome across isolates. The Family-level elementome was (C19.8N2.6 P1.0S18.8K0.7Ca0.1) · 1000 (Fe55.7Mn5.6Sr2.3Zn0.8Ni0.5Se0.3Cu0.2Mo0.1V0.04) mmol Phosphorous-1 versus (C25.4N3.1P1.0S23.1K0.9Ca0.4) · 1000 (Fe66.7Mn6.3Sr7.2Zn0.8Ni0.4Se0.2Cu0.2Mo0.2V0.05) mmol Phosphorous -1 at 27.4 ± 0.4 °C and 30.7 ± 0.01 °C, respectively. Symbiodiniaceae isolates tested here conformed to some, but not all, stoichiometric principles. CONCLUSIONS Elementomes for Symbiodiniaceae diverge from those reported for other marine algae, primarily via lower C:N:P and different micronutrient expressions. Long-term maintenance of Symbiodiniaceae isolates in culture under common nutrient replete conditions suggests isolates have evolutionary conserved preferential uptake for certain elements that allows these unique elementomes to be identified. Micronutrient content (normalised to phosphorous) commonly increased in the Symbiodiniaceae isolates in response to elevated temperature, potentially indicating a common elemental signature to warming.
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Affiliation(s)
- Emma F Camp
- Climate Change Cluster (C3), University of Technology Sydney, PO Box 123, Broadway, Ultimo, NSW, 2007, Australia.
| | - Matthew R Nitschke
- Climate Change Cluster (C3), University of Technology Sydney, PO Box 123, Broadway, Ultimo, NSW, 2007, Australia
- School of Biological Sciences, Victoria University, Wellington, 6012, New Zealand
| | - David Clases
- The Atomic Medicine Initiative, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Australia
- Institute of Chemistry, University of Graz, Graz, 8010, Austria
| | - Raquel Gonzalez de Vega
- The Atomic Medicine Initiative, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Australia
- Institute of Chemistry, University of Graz, Graz, 8010, Austria
| | - Hannah G Reich
- Department of Biological Sciences, University of Rhode Island, 120 Flagg Road, Kingston, RI, 02881, USA
| | - Samantha Goyen
- Climate Change Cluster (C3), University of Technology Sydney, PO Box 123, Broadway, Ultimo, NSW, 2007, Australia
| | - David J Suggett
- Climate Change Cluster (C3), University of Technology Sydney, PO Box 123, Broadway, Ultimo, NSW, 2007, Australia
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5
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Higuchi T, Tanaka K, Shirai K, Yuyama I, Mezaki T, Takahata N, Sano Y. Sulfur assimilation in corals with aposymbiotic and symbiotic zooxanthellae. ENVIRONMENTAL MICROBIOLOGY REPORTS 2021; 13:98-103. [PMID: 33196142 DOI: 10.1111/1758-2229.12908] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 11/11/2020] [Accepted: 11/13/2020] [Indexed: 06/11/2023]
Abstract
Although sulfate ions are the main form of sulfur in the ocean, there is limited knowledge on their use by living organisms. Stable isotope labelling and NanoSIMS analysis were used in this study to clarify how sulfate, in seawater, is assimilated by corals and zooxanthellae at the cellular level. Aposymbiotic and symbiotic coral juveniles from the genus Acropora were incubated for 2 days in filtered seawater with 34 S-labelled sulfate. Further, the labelled corals were incubated for additional 2 days in natural seawater. Mapping of sulfur isotopes (34 S/32 S) showed that the 'hotspots' were enriched in 34 S on a sub-micro level and were heterogeneously distributed in the coral soft tissues. Specifically, 34 S hotspots were found in both the symbiotic zooxanthellae and coral host tissues. In aposymbiotic corals, 34 S was detected in the tissues, indicating that the host corals directly assimilated the sulfate ions without any aid from the zooxanthellae. Even after 2 days in normal seawater, the 34 S label was clearly seen in both symbiotic and aposymbiotic corals, indicating that the assimilated sulfur was retained for at least 2 days.
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Affiliation(s)
- Tomihiko Higuchi
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8564, Japan
| | - Kentaro Tanaka
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8564, Japan
| | - Kotaro Shirai
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8564, Japan
| | - Ikuko Yuyama
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8577, Japan
- Faculty of Science, Yamaguchi University, 1677-1 Yoshida, Yamaguchi City, Yamaguchi, 753-8512, Japan
| | - Takuma Mezaki
- Kuroshio Biological Research Foundation, Nishidomari, Otsuki, Kochi, 788-0333, Japan
| | - Naoto Takahata
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8564, Japan
| | - Yuji Sano
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8564, Japan
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6
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Yoshioka Y, Yamashita H, Suzuki G, Zayasu Y, Tada I, Kanda M, Satoh N, Shoguchi E, Shinzato C. Whole-Genome Transcriptome Analyses of Native Symbionts Reveal Host Coral Genomic Novelties for Establishing Coral-Algae Symbioses. Genome Biol Evol 2020; 13:5981117. [PMID: 33185681 PMCID: PMC7850063 DOI: 10.1093/gbe/evaa240] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2020] [Indexed: 01/14/2023] Open
Abstract
Reef-building corals and photosynthetic, endosymbiotic algae of the family Symbiodiniaceae establish mutualistic relationships that are fundamental to coral biology, enabling coral reefs to support a vast diversity of marine species. Although numerous types of Symbiodiniaceae occur in coral reef environments, Acropora corals select specific types in early life stages. In order to study molecular mechanisms of coral–algal symbioses occurring in nature, we performed whole-genome transcriptomic analyses of Acropora tenuis larvae inoculated with Symbiodinium microadriaticum strains isolated from an Acropora recruit. In order to identify genes specifically involved in symbioses with native symbionts in early life stages, we also investigated transcriptomic responses of Acropora larvae exposed to closely related, nonsymbiotic, and occasionally symbiotic Symbiodinium strains. We found that the number of differentially expressed genes was largest when larvae acquired native symbionts. Repertoires of differentially expressed genes indicated that corals reduced amino acid, sugar, and lipid metabolism, such that metabolic enzymes performing these functions were derived primarily from S. microadriaticum rather than from A. tenuis. Upregulated gene expression of transporters for those metabolites occurred only when coral larvae acquired their natural symbionts, suggesting active utilization of native symbionts by host corals. We also discovered that in Acropora, genes for sugar and amino acid transporters, prosaposin-like, and Notch ligand-like, were upregulated only in response to native symbionts, and included tandemly duplicated genes. Gene duplications in coral genomes may have been essential to establish genomic novelties for coral–algae symbiosis.
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Affiliation(s)
- Yuki Yoshioka
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, Japan.,Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
| | - Hiroshi Yamashita
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, Ishigaki, Okinawa, Japan
| | - Go Suzuki
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, Ishigaki, Okinawa, Japan
| | - Yuna Zayasu
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Ipputa Tada
- Department of Genetics, SOKENDAI (Graduate University for Advanced Studies), Mishima, Shizuoka, Japan
| | - Miyuki Kanda
- DNA Sequencing Section (SQC), Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Noriyuki Satoh
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Eiichi Shoguchi
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Chuya Shinzato
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, Japan
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7
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Yuyama I, Ishikawa M, Nozawa M, Yoshida MA, Ikeo K. Transcriptomic changes with increasing algal symbiont reveal the detailed process underlying establishment of coral-algal symbiosis. Sci Rep 2018; 8:16802. [PMID: 30429501 PMCID: PMC6235891 DOI: 10.1038/s41598-018-34575-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 10/19/2018] [Indexed: 12/21/2022] Open
Abstract
To clarify the establishment process of coral-algal symbiotic relationships, coral transcriptome changes during increasing algal symbiont densities were examined in juvenile corals following inoculation with the algae Symbiodinium goreaui (clade C) and S. trenchii (clade D), and comparison of their transcriptomes with aposymbiotic corals by RNA-sequencing. Since Symbiodinium clades C and D showed very different rates of density increase, comparisons were made of early onsets of both symbionts, revealing that the host behaved differently for each. RNA-sequencing showed that the number of differentially-expressed genes in corals colonized by clade D increased ca. two-fold from 10 to 20 days, whereas corals with clade C showed unremarkable changes consistent with a slow rate of density increase. The data revealed dynamic metabolic changes in symbiotic corals. In addition, the endocytosis pathway was also upregulated, while lysosomal digestive enzymes and the immune system tended to be downregulated as the density of clade D algae increased. The present dataset provides an enormous number of candidate symbiosis-related molecules that exhibit the detailed process by which coral-algal endosymbiosis is established.
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Affiliation(s)
- Ikuko Yuyama
- Faculty of Life and Environmental Sciences, University of Tsukuba, 111 Tennodai, Tsukuba, Ibaraki, 305-8577, Japan.
| | - Masakazu Ishikawa
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Solna, 17 177, Sweden
| | - Masafumi Nozawa
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachioji, Tokyo, 192-0397, Japan
- Center for Genomics and Bioinformatics, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachioji, Tokyo, 192-0397, Japan
| | - Masa-Aki Yoshida
- Marine Biological Science Section, Education and Research Center for Biological Resources, Faculty of Life and Environmental Science, Shimane University, 194 Kamo, Okinoshima-cho, Oki, Shimane, 685-0024, Japan
| | - Kazuho Ikeo
- Center for Information Biology, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
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8
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Raina JB, Clode PL, Cheong S, Bougoure J, Kilburn MR, Reeder A, Forêt S, Stat M, Beltran V, Thomas-Hall P, Tapiolas D, Motti CM, Gong B, Pernice M, Marjo CE, Seymour JR, Willis BL, Bourne DG. Subcellular tracking reveals the location of dimethylsulfoniopropionate in microalgae and visualises its uptake by marine bacteria. eLife 2017; 6. [PMID: 28371617 PMCID: PMC5380433 DOI: 10.7554/elife.23008] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 03/02/2017] [Indexed: 11/30/2022] Open
Abstract
Phytoplankton-bacteria interactions drive the surface ocean sulfur cycle and local climatic processes through the production and exchange of a key compound: dimethylsulfoniopropionate (DMSP). Despite their large-scale implications, these interactions remain unquantified at the cellular-scale. Here we use secondary-ion mass spectrometry to provide the first visualization of DMSP at sub-cellular levels, tracking the fate of a stable sulfur isotope (34S) from its incorporation by microalgae as inorganic sulfate to its biosynthesis and exudation as DMSP, and finally its uptake and degradation by bacteria. Our results identify for the first time the storage locations of DMSP in microalgae, with high enrichments present in vacuoles, cytoplasm and chloroplasts. In addition, we quantify DMSP incorporation at the single-cell level, with DMSP-degrading bacteria containing seven times more 34S than the control strain. This study provides an unprecedented methodology to label, retain, and image small diffusible molecules, which can be transposable to other symbiotic systems. DOI:http://dx.doi.org/10.7554/eLife.23008.001 Sulfur is an essential element for many organisms and environmental processes. Every year, organisms including microalgae produce more than one billion tons of a sulfur-containing compound called DMSP. Some of this DMSP is released into seawater, where it acts as a key nutrient for microscopic organisms and as a foraging cue to attract fish. DMSP is also the precursor of a gas that helps to form clouds. Despite DMSP’s potential large-scale effects, it is still not clear what role it plays in the organisms that produce it, or how it is transferred from the microalgae that produce it to the bacteria that use it. It is thought that DMSP could potentially protect the cells from sudden changes in the amount of salt in the seawater (salinity) or from other damage, such as oxidative stress – a build-up of harmful chemicals inside cells. In a controlled setting using artificial seawater, Raina et al. used high-resolution imaging and chemical analysis to track the journey of DMSP from microalgae to recipient bacteria. The results show that similar to land plants, algae store DMSP in the compartments that regulate cell pressure and photosynthesis. The presence of DMSP in these locations also supports its proposed role in protecting cells from changes in salinity or oxidative damage. A future step will be to identify the genes involved in producing DMSP in microalgae. This knowledge could be used to create mutants that are either incapable of producing this molecule or that overproduce it. In combination with the high-resolution imaging techniques described here, this will allow researchers to fully understand the role that DMSP plays in these organisms. DOI:http://dx.doi.org/10.7554/eLife.23008.002
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Affiliation(s)
- Jean-Baptiste Raina
- AIMS@JCU, James Cook University, Townsville, Australia.,Australian Institute of Marine Science, Townsville, Australia.,Climate Change Cluster, University of Technology Sydney, Sydney, Australia.,ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia.,College of Science and Engineering, James Cook University, Townsville, Australia
| | - Peta L Clode
- The Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Crawley, Australia.,Oceans Institute, The University of Western Australia, Crawley, Australia
| | - Soshan Cheong
- Mark Wainwright Analytical Centre, University of New South Wales, Kensington, Australia
| | - Jeremy Bougoure
- The Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Crawley, Australia.,School of Earth and Environment, The University of Western Australia, Crawley, Australia
| | - Matt R Kilburn
- The Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Crawley, Australia
| | - Anthony Reeder
- The Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Crawley, Australia
| | - Sylvain Forêt
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia.,Research School of Biology, Australian National University, Canberra, Australia
| | - Michael Stat
- Trace and Environmental DNA Laboratory, Department of Environment and Agriculture, Curtin University, Perth, Australia
| | - Victor Beltran
- Australian Institute of Marine Science, Townsville, Australia
| | | | - Dianne Tapiolas
- Australian Institute of Marine Science, Townsville, Australia
| | - Cherie M Motti
- AIMS@JCU, James Cook University, Townsville, Australia.,Australian Institute of Marine Science, Townsville, Australia
| | - Bill Gong
- Mark Wainwright Analytical Centre, University of New South Wales, Kensington, Australia
| | - Mathieu Pernice
- Climate Change Cluster, University of Technology Sydney, Sydney, Australia
| | - Christopher E Marjo
- Mark Wainwright Analytical Centre, University of New South Wales, Kensington, Australia
| | - Justin R Seymour
- Climate Change Cluster, University of Technology Sydney, Sydney, Australia
| | - Bette L Willis
- AIMS@JCU, James Cook University, Townsville, Australia.,ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia.,College of Science and Engineering, James Cook University, Townsville, Australia
| | - David G Bourne
- Australian Institute of Marine Science, Townsville, Australia.,College of Science and Engineering, James Cook University, Townsville, Australia
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