1
|
Park H, Kim HS, Abassi S, Bui QTN, Ki JS. Two novel glutathione S-transferase (GST) genes in the toxic marine dinoflagellate Alexandrium pacificum and their transcriptional responses to environmental contaminants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 915:169983. [PMID: 38215848 DOI: 10.1016/j.scitotenv.2024.169983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 01/02/2024] [Accepted: 01/05/2024] [Indexed: 01/14/2024]
Abstract
The present study identified two novel glutathione S-transferase (GST) genes from the toxic dinoflagellate Alexandrium pacificum and examined their molecular characteristics and transcriptional responses to algicides and environmental contaminants. Bioinformatic analysis revealed that both ApGSTs are cytosolic, belonging to the chi-like class (ApGST1) and an undefined class (ApGST2). The overall expression of ApGSTs showed similar patterns depending on the exposed contaminants, while they were differently regulated by polychlorinated biphenyl (PCB). Copper treatments (CuCl2 and CuSO4) did not significantly induce the expression of ApGSTs. The highest up-regulations of ApGST1 and ApGST2 were under 6-h treatments of 0.10 and 0.50 mg L-1 NaOCl. Interestingly, only ApGST1 increased significantly after 0.10, 0.50, and 1.00 mg L-1 of PCB exposure (6 h). Intracellular reactive oxygen species (ROS) increased considerably under NaOCl; however, it was not significantly higher in the PCB-treated cells. GST activity was increased by NaOCl and PCB treatments, but only PCB caused apoptosis. These results suggest that GSTs are involved in the first line of phase II detoxification, protecting dinoflagellate cells against oxidative damage.
Collapse
Affiliation(s)
- Hyunjun Park
- Department of Life Science, Sangmyung University, Seoul, South Korea
| | - Han-Sol Kim
- Department of Life Science, Sangmyung University, Seoul, South Korea
| | - Sofia Abassi
- Department of Life Science, Sangmyung University, Seoul, South Korea
| | - Quynh Thi Nhu Bui
- Department of Life Science, Sangmyung University, Seoul, South Korea
| | - Jang-Seu Ki
- Department of Life Science, Sangmyung University, Seoul, South Korea; Department of Biotechnology, Sangmyung University, Seoul, South Korea.
| |
Collapse
|
2
|
Lu C, Zhang P, Li S, Cheng M, Duan D. Isolation and characterization of glutathione S-transferase genes and their transcripts in Saccharina japonica (Laminariales, Phaeophyceae) during development and under abiotic stress. BMC PLANT BIOLOGY 2023; 23:436. [PMID: 37723443 PMCID: PMC10506224 DOI: 10.1186/s12870-023-04430-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 08/31/2023] [Indexed: 09/20/2023]
Abstract
BACKGROUND Glutathione S-transferase (GST) is a crucial enzyme for metabolism, detoxification, and stress resistance in organisms. Many GSTs have been identified in seaweeds, but the isolation and functional analysis of GSTs in Saccharina japonica have not been completed. RESULT In this study, a total of 32 SjGST genes, localized on 10 scaffolds and 6 contigs, were identified and categorized into three groups. Most of these SjGSTs were presumed to be distributed in the cytoplasm. Tandem duplication had a significant influence on the expansion of the SjGST gene family. Functional analysis of cis-acting elements in the promoter regions demonstrated that SjGSTs enhance the stress resistance of the kelp. Quantitative real-time PCR tests confirmed that SjGSTs positively influence S. japonica sporophytes under stress from low salinity, drought, and high temperature. Recombinant yeast tests further affirmed the role of SjGSTs in stress resistance; SjGSTs improved the growth rate of recombinant yeast under 1.5 M NaCl or 8 mM H2O2. Analysis of biochemical parameters indicated that the optimum temperatures for SjGST20 and SjGST22 were 20 °C, and the optimum pH values were 7.0 and 8.0 for SjGST20 and SjGST22, respectively. The Km values for the substrate 1-chloro-2,4-dinitrobenzene (CDNB) were 2.706 mM and 0.674 mM and were 6.146 mM and 3.559 mM for the substrate glutathione (GSH) for SjGST20 and SjGST22, respectively. CONCLUSION SjGSTs are important stress resistant genes in S. japonica. This research results will enhance our understanding the function of GSTs in brown seaweeds, and explained its functional roles in stress resistance in marine environments.
Collapse
Affiliation(s)
- Chang Lu
- Key Lab of Breeding Biotechnology & Sustainable Aquaculture, Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, P. R. China
- Department of Biological Engineering, College of Life Science, Yantai University, Yantai, 264005, China
| | - Pengyan Zhang
- Functional Lab for Marine Biology and Biotechnology, National Laboratory for Marine Science and Technology, Qingdao, 266071, China
- Division of Mariculture Ecology and Technology, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, China
| | - Shuang Li
- Key Lab of Breeding Biotechnology & Sustainable Aquaculture, Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, P. R. China
- Functional Lab for Marine Biology and Biotechnology, National Laboratory for Marine Science and Technology, Qingdao, 266071, China
- University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Mengzhen Cheng
- Key Lab of Breeding Biotechnology & Sustainable Aquaculture, Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, P. R. China
- Functional Lab for Marine Biology and Biotechnology, National Laboratory for Marine Science and Technology, Qingdao, 266071, China
- University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Delin Duan
- Key Lab of Breeding Biotechnology & Sustainable Aquaculture, Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, P. R. China.
| |
Collapse
|
3
|
Zhang X, Zhang J, Wang Y, Xu D, Fan X, Zhang Y, Ma J, Ye N. The oxylipin messenger 1-octen-3-ol induced rapid responses in kelp Macrocystis pyrifera. PHYSIOLOGIA PLANTARUM 2021; 172:1641-1652. [PMID: 33547806 DOI: 10.1111/ppl.13358] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 01/27/2021] [Accepted: 02/02/2021] [Indexed: 06/12/2023]
Abstract
Oxylipins are important oxygenated derivatives of fatty acids that regulate a variety of plant physiological and pathological processes in response to specific external challenges. A large body of evidence has indicated that algae can also produce a surprisingly diverse array of volatile oxylipins, yet little is known about the roles of volatile oxylipins as defense signals in macroalgae. In this study, the kelp Macrocystis pyrifera was treated by the oxylipin messenger 1-octen-3-ol and then a genome-wide gene expression profile and fatty acid spectrum analysis were performed. We found that M. pyrifera responded rapidly to the exposure of the oxylipin messenger 1-octen-3-ol. It regulated the expression levels of genes mainly involved in signal transduction, lipid metabolism, oxidation prevention, cell wall synthesis, photosynthesis, and development. Moreover, 1-octen-3-ol treatments decreased several types of total fatty acid contents and increased free fatty acid contents, especially for the C18 and C20 fatty acids. In addition, it decreased the content of indole-3-acetic acid, abscisic acid, and zeatin and increased the gibberellic acid content. Our findings demonstrated that 1-octen-3-ol is an available inducer for M. pyrifera, which is capable of rapidly upregulating kelp's defense response.
Collapse
Affiliation(s)
- Xiaowen Zhang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
- Function Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Jian Zhang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Yitao Wang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Dong Xu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
- Function Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Xiao Fan
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Yan Zhang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Jian Ma
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Naihao Ye
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
- Function Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| |
Collapse
|
4
|
Li H, Monteiro C, Heinrich S, Bartsch I, Valentin K, Harms L, Glöckner G, Corre E, Bischof K. Responses of the kelp Saccharina latissima (Phaeophyceae) to the warming Arctic: from physiology to transcriptomics. PHYSIOLOGIA PLANTARUM 2020; 168:5-26. [PMID: 31267544 DOI: 10.1111/ppl.13009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/31/2019] [Accepted: 06/27/2019] [Indexed: 06/09/2023]
Abstract
The Arctic region is currently facing substantial environmental changes due to global warming. Melting glaciers cause reduced salinity environments in coastal Arctic habitats, which may be stressful for kelp beds. To investigate the responses of the kelp Saccharina latissima to the warming Arctic, we studied the transcriptomic changes of S. latissima from Kongsfjorden (Svalbard, Norway) over a 24-hour exposure to two salinities (Absolute Salinity [SA ] 20 and 30) after a 7-day pre-acclimation at three temperatures (0, 8 and 15°C). In addition, corresponding physiological data were assessed during an 11-days salinity/temperature experiment. Growth and maximal quantum yield for photosystem II fluorescence were positively affected by increased temperature during acclimation, whereas hyposalinity caused negative effects at the last day of treatment. In contrast, hyposalinity induced marked changes on the transcriptomic level. Compared to the control (8°C - SA 30), the 8°C - SA 20 exhibited the highest number of differentially expressed genes (DEGs), followed by the 0°C - SA 20. Comparisons indicate that S. latissima tends to convert its energy from primary metabolism (e.g. photosynthesis) to antioxidant activity under hyposaline stress. The increase in physiological performance at 15°C shows that S. latissima in the Arctic region can adjust and might even benefit from increased temperatures. However, in Arctic fjord environments its performance might become impaired by decreased salinity as a result of ice melting.
Collapse
Affiliation(s)
- Huiru Li
- Fisheries College, Ocean University of China, Qingdao, 266003, China
- Marine Botany, Faculty Biology/Chemistry, University of Bremen, Bremen, 28359, Germany
| | - Cátia Monteiro
- Marine Botany, Faculty Biology/Chemistry, University of Bremen, Bremen, 28359, Germany
- Station Biologique de Roscoff, plateforme ABiMS, CNRS: FR2424, Sorbonne Université (UPMC), Roscoff, 29680, France
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Roscoff, 29680, France
| | - Sandra Heinrich
- Molecular Plant Genetics, Institute for Plant Science and Microbiology, University of Hamburg, Hamburg, 22609, Germany
| | - Inka Bartsch
- Alfred-Wegener-Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, 27570, Germany
| | - Klaus Valentin
- Alfred-Wegener-Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, 27570, Germany
| | - Lars Harms
- Alfred-Wegener-Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, 27570, Germany
| | - Gernot Glöckner
- Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, 50931, Germany
| | - Erwan Corre
- Station Biologique de Roscoff, plateforme ABiMS, CNRS: FR2424, Sorbonne Université (UPMC), Roscoff, 29680, France
| | - Kai Bischof
- Marine Botany, Faculty Biology/Chemistry, University of Bremen, Bremen, 28359, Germany
| |
Collapse
|
5
|
Machado Monteiro CM, Li H, Bischof K, Bartsch I, Valentin KU, Corre E, Collén J, Harms L, Glöckner G, Heinrich S. Is geographical variation driving the transcriptomic responses to multiple stressors in the kelp Saccharina latissima? BMC PLANT BIOLOGY 2019; 19:513. [PMID: 31775614 PMCID: PMC6881991 DOI: 10.1186/s12870-019-2124-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 11/07/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Kelps (Laminariales, Phaeophyceae) are brown macroalgae of utmost ecological, and increasingly economic, importance on temperate to polar rocky shores. Omics approaches in brown algae are still scarce and knowledge of their acclimation mechanisms to the changing conditions experienced in coastal environments can benefit from the application of RNA-sequencing. Despite evidence of ecotypic differentiation, transcriptomic responses from distinct geographical locations have, to our knowledge, never been studied in the sugar kelp Saccharina latissima so far. RESULTS In this study we investigated gene expression responses using RNA-sequencing of S. latissima from environments with contrasting temperature and salinity conditions - Roscoff, in temperate eastern Atlantic, and Spitsbergen in the Arctic. Juvenile sporophytes derived from uniparental stock cultures from both locations were pre-cultivated at 8 °C and SA 30. Sporophytes acclimated to 0 °C, 8 °C and 15 °C were exposed to a low salinity treatment (SA 20) for 24 h. Hyposalinity had a greater impact at the transcriptomic level than the temperature alone, and its effects were modulated by temperature. Namely, photosynthesis and pigment synthesis were extensively repressed by low salinity at low temperatures. Although some responses were shared among sporophytes from the different sites, marked differences were revealed by principal component analysis, differential expression and GO enrichment. The interaction between low temperature and low salinity drove the largest changes in gene expression in sporophytes from Roscoff while specimens from Spitsbergen required more metabolic adjustment at higher temperatures. Moreover, genes related to cell wall adjustment were differentially expressed between Spitsbergen and Roscoff control samples. CONCLUSIONS Our study reveals interactive effects of temperature and salinity on transcriptomic profiles in S. latissima. Moreover, our data suggest that under identical culture conditions sporophytes from different locations diverge in their transcriptomic responses. This is probably connected to variations in temperature and salinity in their respective environment of origin. The current transcriptomic results support the plastic response pattern in sugar kelp which is a species with several reported ecotypes. Our data provide the baseline for a better understanding of the underlying processes of physiological plasticity and may help in the future to identify strains adapted to specific environments and its genetic control.
Collapse
Affiliation(s)
- Cátia Marina Machado Monteiro
- Marine Botany, Faculty Biology/Chemistry, University of Bremen, Bremen, Germany
- Station Biologique de Roscoff, plateforme ABiMS, CNRS: FR2424, Sorbonne Université (UPMC), 29680 Roscoff, France
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, 29680 Roscoff, France
| | - Huiru Li
- Marine Botany, Faculty Biology/Chemistry, University of Bremen, Bremen, Germany
- Fisheries College, Ocean University of China, Qingdao, China
| | - Kai Bischof
- Marine Botany, Faculty Biology/Chemistry, University of Bremen, Bremen, Germany
| | - Inka Bartsch
- Alfred-Wegener-Institute, Helmholtz Centre for Marine and Polar Research, Bremerhaven, Germany
| | - Klaus Ulrich Valentin
- Alfred-Wegener-Institute, Helmholtz Centre for Marine and Polar Research, Bremerhaven, Germany
| | - Erwan Corre
- Station Biologique de Roscoff, plateforme ABiMS, CNRS: FR2424, Sorbonne Université (UPMC), 29680 Roscoff, France
| | - Jonas Collén
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, 29680 Roscoff, France
| | - Lars Harms
- Alfred-Wegener-Institute, Helmholtz Centre for Marine and Polar Research, Bremerhaven, Germany
| | - Gernot Glöckner
- Institute for Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - Sandra Heinrich
- Institute for Plant Science and Microbiology, University of Hamburg, Hamburg, Germany
| |
Collapse
|
6
|
Zhang Y, Wang X, Shan T, Pang S, Xu N. Transcriptome profiling of the meristem tissue of Saccharina japonica (Phaeophyceae, Laminariales) under severe stress of copper. Mar Genomics 2019; 47:100671. [PMID: 30910511 DOI: 10.1016/j.margen.2019.03.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 03/18/2019] [Accepted: 03/18/2019] [Indexed: 02/08/2023]
Abstract
Copper (Cu) is an essential metal involved in many physiological processes of living organisms. However, beyond a certain threshold, Cu can become highly toxic. For instance, in the summer sporeling production of the economic kelp Saccharina japonica, the excess Cu accidently released from the low-quality alloys of the refrigerating machine was deadly to the seedlings and led to the failure of hatchery operations. However, the molecular basis underlying high toxicity of Cu remains unclear. In this study, juvenile sporophytes were cultured in seawater containing different concentrations of Cu2+ (10, 100, and 200 μg L-1). Bleaching was observed in the meristem of individuals in the 100 and 200 μg L-1 treatment groups on the third day, indicating that Cu has caused severe harm at these concentrations. RNA-Seq was used to profile transcriptomic changes under different Cu2+ concentrations. Compared with the control, the number of differentially expressed genes (DEGs) was 11,350 (4944 up- and 6406 down-regulated) in the 200 μg L-1 treatment group and 2868 (1075 up- and 1793 down-regulated) in the 100 μg L-1 treatment group, whereas much fewer DEGs were detected in the 10 μg L-1 treatment group. Genes coding for glutathione-S-transferase and vanadium-dependent bromoperoxidase and iodoperoxidase were found to be remarkably regulated, especially in the 200 μg L-1 treatment group. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that only down-regulated DEGs were enriched. There were 45 enriched GO terms and four enriched KEGG pathways common to the 100 and 200 μg L-1 treatment groups, which were associated with diverse essential biological processes such as photosynthesis, protein synthesis, redox activity, and metabolism and biosynthesis of functional biomolecules, among others. Suppression of these biological processes at the transcriptional level likely contributes to the observed high toxicity of Cu2+ in S. japonica.
Collapse
Affiliation(s)
- Yurong Zhang
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China; Marine Fishery Institute of Zhejiang Province, Key Lab of Mariculture and Enhancement of Zhejiang province, 316100 Zhoushan, China
| | - Xuemei Wang
- CAS Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 7 Nanhai Road, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tifeng Shan
- CAS Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 7 Nanhai Road, Qingdao 266071, China.
| | - Shaojun Pang
- CAS Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 7 Nanhai Road, Qingdao 266071, China.
| | - Nianjun Xu
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| |
Collapse
|
7
|
Strittmatter M, Grenville-Briggs LJ, Breithut L, Van West P, Gachon CMM, Küpper FC. Infection of the brown alga Ectocarpus siliculosus by the oomycete Eurychasma dicksonii induces oxidative stress and halogen metabolism. PLANT, CELL & ENVIRONMENT 2016; 39:259-71. [PMID: 25764246 PMCID: PMC4949667 DOI: 10.1111/pce.12533] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 11/03/2014] [Accepted: 02/07/2015] [Indexed: 05/24/2023]
Abstract
Pathogens are increasingly being recognized as key evolutionary and ecological drivers in marine ecosystems. Defence mechanisms of seaweeds, however, have mostly been investigated by mimicking infection using elicitors. We have established an experimental pathosystem between the genome brown model seaweed Ectocarpus siliculosus and the oomycete Eurychasma dicksonii as a powerful new tool to investigate algal responses to infection. Using proteomics, we identified 21 algal proteins differentially accumulated in response to Eu. dicksonii infection. These include classical algal stress response proteins such as a manganese superoxide dismutase, heat shock proteins 70 and a vanadium bromoperoxidase. Transcriptional profiling by qPCR confirmed the induction of the latter during infection. The accumulation of hydrogen peroxide was observed at different infection stages via histochemical staining. Inhibitor studies confirmed that the main source of hydrogen peroxide is superoxide converted by superoxide dismutase. Our data give an unprecedented global overview of brown algal responses to pathogen infection, and highlight the importance of oxidative stress and halogen metabolism in these interactions. This suggests overlapping defence pathways with herbivores and abiotic stresses. We also identify previously unreported actors, in particular a Rad23 and a plastid-lipid-associated protein, providing novel insights into the infection and defence processes in brown algae.
Collapse
Affiliation(s)
- Martina Strittmatter
- The Scottish Association for Marine Science, Scottish Marine Institute, Oban, Argyll, Scotland, PA37 1QA, UK
- Aberdeen Oomycete Laboratory, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, AB25 2ZD, UK
| | - Laura J Grenville-Briggs
- Aberdeen Oomycete Laboratory, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, AB25 2ZD, UK
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, 230 53, Sweden
| | - Lisa Breithut
- Fachbereich Biologie, Universität Konstanz, Konstanz, D-78457, Germany
| | - Pieter Van West
- Aberdeen Oomycete Laboratory, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland, AB25 2ZD, UK
| | - Claire M M Gachon
- The Scottish Association for Marine Science, Scottish Marine Institute, Oban, Argyll, Scotland, PA37 1QA, UK
| | - Frithjof C Küpper
- The Scottish Association for Marine Science, Scottish Marine Institute, Oban, Argyll, Scotland, PA37 1QA, UK
- Oceanlab, University of Aberdeen, Main Street, Newburgh, Scotland, AB41 6AA, UK
| |
Collapse
|
8
|
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.
Collapse
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.
| |
Collapse
|
9
|
PmMGST3, a novel microsomal glutathione S-transferase gene in the dinoflagellate Prorocentrum minimum, is a potential biomarker of oxidative stress. Gene 2014; 546:378-85. [DOI: 10.1016/j.gene.2014.05.046] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 05/13/2014] [Accepted: 05/21/2014] [Indexed: 11/24/2022]
|
10
|
Ritter A, Dittami SM, Goulitquer S, Correa JA, Boyen C, Potin P, Tonon T. Transcriptomic and metabolomic analysis of copper stress acclimation in Ectocarpus siliculosus highlights signaling and tolerance mechanisms in brown algae. BMC PLANT BIOLOGY 2014; 14:116. [PMID: 24885189 PMCID: PMC4108028 DOI: 10.1186/1471-2229-14-116] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 04/22/2014] [Indexed: 05/23/2023]
Abstract
BACKGROUND Brown algae are sessile macro-organisms of great ecological relevance in coastal ecosystems. They evolved independently from land plants and other multicellular lineages, and therefore hold several original ontogenic and metabolic features. Most brown algae grow along the coastal zone where they face frequent environmental changes, including exposure to toxic levels of heavy metals such as copper (Cu). RESULTS We carried out large-scale transcriptomic and metabolomic analyses to decipher the short-term acclimation of the brown algal model E. siliculosus to Cu stress, and compared these data to results known for other abiotic stressors. This comparison demonstrates that Cu induces oxidative stress in E. siliculosus as illustrated by the transcriptomic overlap between Cu and H2O2 treatments. The common response to Cu and H2O2 consisted in the activation of the oxylipin and the repression of inositol signaling pathways, together with the regulation of genes coding for several transcription-associated proteins. Concomitantly, Cu stress specifically activated a set of genes coding for orthologs of ABC transporters, a P1B-type ATPase, ROS detoxification systems such as a vanadium-dependent bromoperoxidase, and induced an increase of free fatty acid contents. Finally we observed, as a common abiotic stress mechanism, the activation of autophagic processes on one hand and the repression of genes involved in nitrogen assimilation on the other hand. CONCLUSIONS Comparisons with data from green plants indicate that some processes involved in Cu and oxidative stress response are conserved across these two distant lineages. At the same time the high number of yet uncharacterized brown alga-specific genes induced in response to copper stress underlines the potential to discover new components and molecular interactions unique to these organisms. Of particular interest for future research is the potential cross-talk between reactive oxygen species (ROS)-, myo-inositol-, and oxylipin signaling.
Collapse
Affiliation(s)
- Andrés Ritter
- UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, Sorbonne Universités, CS 90074, F-29688 Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688 Roscoff cedex, France
- Departamento de Ecología, Center of Applied Ecology & Sustainability, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Present addresses: Department of Plant Systems Biology, VIB and Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, Ghent B-9052, Belgium
| | - Simon M Dittami
- UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, Sorbonne Universités, CS 90074, F-29688 Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688 Roscoff cedex, France
| | - Sophie Goulitquer
- Plate-forme MetaboMER, CNRS & UPMC, FR2424, Station Biologique, 29680 Roscoff, France
| | - Juan A Correa
- Departamento de Ecología, Center of Applied Ecology & Sustainability, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Catherine Boyen
- UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, Sorbonne Universités, CS 90074, F-29688 Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688 Roscoff cedex, France
| | - Philippe Potin
- UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, Sorbonne Universités, CS 90074, F-29688 Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688 Roscoff cedex, France
| | - Thierry Tonon
- UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, Sorbonne Universités, CS 90074, F-29688 Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688 Roscoff cedex, France
| |
Collapse
|
11
|
Wu X, Tronholm A, Cáceres EF, Tovar-Corona JM, Chen L, Urrutia AO, Hurst LD. Evidence for deep phylogenetic conservation of exonic splice-related constraints: splice-related skews at exonic ends in the brown alga Ectocarpus are common and resemble those seen in humans. Genome Biol Evol 2013; 5:1731-45. [PMID: 23902749 PMCID: PMC3787667 DOI: 10.1093/gbe/evt115] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2013] [Indexed: 12/22/2022] Open
Abstract
The control of RNA splicing is often modulated by exonic motifs near splice sites. Chief among these are exonic splice enhancers (ESEs). Well-described ESEs in mammals are purine rich and cause predictable skews in codon and amino acid usage toward exonic ends. Looking across species, those with relatively abundant intronic sequence are those with the more profound end of exon skews, indicative of exonization of splice site recognition. To date, the only intron-rich species that have been analyzed are mammals, precluding any conclusions about the likely ancestral condition. Here, we examine the patterns of codon and amino acid usage in the vicinity of exon-intron junctions in the brown alga Ectocarpus siliculosus, a species with abundant large introns, known SR proteins, and classical splice sites. We find that amino acids and codons preferred/avoided at both 3' and 5' ends in Ectocarpus, of which there are many, tend, on average, to also be preferred/avoided at the same exon ends in humans. Moreover, the preferences observed at the 5' ends of exons are largely the same as those at the 3' ends, a symmetry trend only previously observed in animals. We predict putative hexameric ESEs in Ectocarpus and show that these are purine rich and that there are many more of these identified as functional ESEs in humans than expected by chance. These results are consistent with deep phylogenetic conservation of SR protein binding motifs. Assuming codons preferred near boundaries are "splice optimal" codons, in Ectocarpus, unlike Drosophila, splice optimal and translationally optimal codons are not mutually exclusive. The exclusivity of translationally optimal and splice optimal codon sets is thus not universal.
Collapse
Affiliation(s)
- XianMing Wu
- Department of Biology and Biochemistry, University of Bath, Somerset, United Kingdom
| | - Ana Tronholm
- Department of Biology and Biochemistry, University of Bath, Somerset, United Kingdom
- Present address: Department of Biological Sciences, University of Alabama, Mary Harmon Bryant Hall, Tuscaloosa, AL
| | - Eva Fernández Cáceres
- Department of Biology and Biochemistry, University of Bath, Somerset, United Kingdom
| | - Jaime M. Tovar-Corona
- Department of Biology and Biochemistry, University of Bath, Somerset, United Kingdom
| | - Lu Chen
- Human Genetics, Wellcome Trust Sanger Institute, Genome Campus, Hinxton, United Kingdom
| | - Araxi O. Urrutia
- Department of Biology and Biochemistry, University of Bath, Somerset, United Kingdom
| | - Laurence D. Hurst
- Department of Biology and Biochemistry, University of Bath, Somerset, United Kingdom
| |
Collapse
|
12
|
Dittami SM, Gravot A, Goulitquer S, Rousvoal S, Peters AF, Bouchereau A, Boyen C, Tonon T. Towards deciphering dynamic changes and evolutionary mechanisms involved in the adaptation to low salinities in Ectocarpus (brown algae). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 71:366-77. [PMID: 22394375 DOI: 10.1111/j.1365-313x.2012.04982.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Colonizations of freshwater by marine species are rare events, and little information is known about the underlying mechanisms. Brown algae are an independent lineage of photosynthetic and multicellular organisms from which few species inhabit freshwater. As a marine alga that is also found in freshwater, Ectocarpus is of particular interest for studying the transition between these habitats. To gain insights into mechanisms of the transition, we examined salinity tolerance and adaptations to low salinities in a freshwater strain of Ectocarpus on physiological and molecular levels. We show that this isolate belongs to a widely distributed and highly stress-resistant clade, and differed from the genome-sequenced marine strain in its tolerance of low salinities. It also exhibited profound, but reversible, morphological, physiological, and transcriptomic changes when transferred to seawater. Although gene expression profiles were similar in both strains under identical conditions, metabolite and ion profiles differed strongly, the freshwater strain exhibiting e.g. higher cellular contents of amino acids and nitrate, higher contents of n-3 fatty acids, and lower intracellular mannitol and sodium concentrations. Moreover, several stress markers were noted in the freshwater isolate in seawater. This finding suggests that, while high stress tolerance and plasticity may be prerequisites for the colonization of freshwater, genomic alterations have occurred that produced permanent changes in the metabolite profiles to stabilize the transition.
Collapse
Affiliation(s)
- Simon M Dittami
- UPMC Univ Paris 6, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680, Roscoff, France
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Tonon T, Eveillard D, Prigent S, Bourdon J, Potin P, Boyen C, Siegel A. Toward systems biology in brown algae to explore acclimation and adaptation to the shore environment. OMICS : A JOURNAL OF INTEGRATIVE BIOLOGY 2011; 15:883-92. [PMID: 22136637 DOI: 10.1089/omi.2011.0089] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Brown algae belong to a phylogenetic lineage distantly related to land plants and animals. They are almost exclusively found in the intertidal zone, a harsh and frequently changing environment where organisms are submitted to marine and terrestrial constraints. In relation with their unique evolutionary history and their habitat, they feature several peculiarities, including at the level of their primary and secondary metabolism. The establishment of Ectocarpus siliculosus as a model organism for brown algae has represented a framework in which several omics techniques have been developed, in particular, to study the response of these organisms to abiotic stresses. With the recent publication of medium to high throughput profiling data, it is now possible to envision integrating observations at the cellular scale to apply systems biology approaches. As a first step, we propose a protocol focusing on integrating heterogeneous knowledge gained on brown algal metabolism. The resulting abstraction of the system will then help understanding how brown algae cope with changes in abiotic parameters within their unique habitat, and to decipher some of the mechanisms underlying their (1) acclimation and (2) adaptation, respectively consequences of (1) the behavior or (2) the topology of the system resulting from the integrative approach.
Collapse
Affiliation(s)
- Thierry Tonon
- UPMC Univ Paris 6 , UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France.
| | | | | | | | | | | | | |
Collapse
|
14
|
Rousvoal S, Groisillier A, Dittami SM, Michel G, Boyen C, Tonon T. Mannitol-1-phosphate dehydrogenase activity in Ectocarpus siliculosus, a key role for mannitol synthesis in brown algae. PLANTA 2011; 233:261-73. [PMID: 20981555 DOI: 10.1007/s00425-010-1295-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 09/26/2010] [Indexed: 05/30/2023]
Abstract
Mannitol represents a major end product of photosynthesis in brown algae (Phaeophyceae), and is, with the β-1,3-glucan laminarin, the main form of carbon storage for these organisms. Despite its importance, little is known about the genes and enzymes responsible for the metabolism of mannitol in these seaweeds. Taking benefit of the sequencing of the Ectocarpus siliculosus genome, we focussed our attention on the first step of the synthesis of mannitol (reduction of the photo-assimilate fructose-6-phosphate), catalysed by the mannitol-1-phosphate dehydrogenase (M1PDH). This activity was measured in algal extracts, and was shown to be regulated by NaCl concentration in the reaction medium. Genomic analysis revealed the presence of three putative M1PDH genes (named EsM1PHD1, EsM1PDH2 and EsM1PDH3). Sequence comparison with orthologs demonstrates the modular architecture of EsM1PHD1 and EsM1PDH2, with an additional N-terminal domain of unknown function. In addition, gene expression experiments carried out on samples harvested through the diurnal cycle, and after several short-term saline and oxidative stress treatments, showed that EsM1PDH1 is the most highly expressed of these genes, whatever the conditions tested. In order to assess the activity of the corresponding protein, this gene was expressed in Escherichia coli. Cell-free extracts prepared from bacteria containing EsM1PDH1 displayed higher M1PDH activity than bacteria transformed with an empty plasmid. Further characterisation of recombinant EsM1PDH1 activity revealed its very narrow substrate specificity, salt regulation, and sensitivity towards an inhibitor of SH-enzymes.
Collapse
Affiliation(s)
- Sylvie Rousvoal
- UPMC Univ Paris 6, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29682 Roscoff, France
| | | | | | | | | | | |
Collapse
|
15
|
Dittami SM, Proux C, Rousvoal S, Peters AF, Cock JM, Coppée JY, Boyen C, Tonon T. Microarray estimation of genomic inter-strain variability in the genus Ectocarpus (Phaeophyceae). BMC Mol Biol 2011; 12:2. [PMID: 21226968 PMCID: PMC3027116 DOI: 10.1186/1471-2199-12-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 01/13/2011] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Brown algae of the genus Ectocarpus exhibit high levels of genetic diversity and variability in morphological and physiological characteristics. With the establishment of E. siliculosus as a model and the availability of a complete genome sequence, it is now of interest to analyze variability among different species, ecotypes, and strains of the genus Ectocarpus both at the genome and the transcriptome level. RESULTS We used an E. siliculosus gene expression microarray based on EST sequences from the genome-sequenced strain (reference strain) to carry out comparative genome hybridizations for five Ectocarpus strains: four E. siliculosus isolates (the male genome strain, a female strain used for outcrosses with the genome strain, a strain isolated from freshwater, and a highly copper-tolerant strain), as well as one strain of the sister species E. fasciculatus. Our results revealed significant genomic differences between ecotypes of the same species, and enable the selection of conserved probes for future microarray experiments with these strains. In the two closely related strains (a male and a female strain used for crosses), genomic differences were also detected, but concentrated in two smaller genomic regions, one of which corresponds to a viral insertion site. CONCLUSION The high variability between strains supports the concept of E. siliculosus as a complex of cryptic species. Moreover, our data suggest that several parts of the Ectocarpus genome may have evolved at different rates: high variability was detected particularly in transposable elements and fucoxanthin chlorophyll a/c binding proteins.
Collapse
Affiliation(s)
- Simon M Dittami
- UPMC Univ Paris 6, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
- CNRS, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
- Current Address: Department of Biology, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo, Norway
| | - Caroline Proux
- Institut Pasteur, Plate-Forme 2- Puces à ADN, 25 rue du docteur Roux, 75724 Paris Cedex 15, France
| | - Sylvie Rousvoal
- UPMC Univ Paris 6, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
- CNRS, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
| | - Akira F Peters
- BEZHIN ROSKO, 40 rue des pêcheurs, 29250 Santec, France
- MBA Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - J Mark Cock
- UPMC Univ Paris 6, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
- CNRS, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
| | - Jean-Yves Coppée
- Institut Pasteur, Plate-Forme 2- Puces à ADN, 25 rue du docteur Roux, 75724 Paris Cedex 15, France
| | - Catherine Boyen
- UPMC Univ Paris 6, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
- CNRS, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
| | - Thierry Tonon
- UPMC Univ Paris 6, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
- CNRS, UMR 7139 Marine Plants and Biomolecules, Station Biologique, 29680 Roscoff, France
| |
Collapse
|
16
|
Ritter A, Ubertini M, Romac S, Gaillard F, Delage L, Mann A, Cock JM, Tonon T, Correa JA, Potin P. Copper stress proteomics highlights local adaptation of two strains of the model brown alga Ectocarpus siliculosus. Proteomics 2010; 10:2074-88. [PMID: 20373519 DOI: 10.1002/pmic.200900004] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2009] [Accepted: 11/19/2009] [Indexed: 11/10/2022]
Abstract
Ectocarpus siliculosus is a cosmopolitan brown alga with capacity to thrive in copper enriched environments. Analysis of copper toxicity was conducted in two strains of E. siliculosus isolated from (i) an uncontaminated coast in southern Peru (Es32) and (ii) a copper polluted rocky beach in northern Chile (Es524). Es32 was more sensitive than Es524, with toxicity detected at 50 microg/L Cu, whereas Es524 displayed negative effects only when exposed to 250 microg/L Cu. Differential soluble proteome profiling for each strain exposed to sub-lethal copper levels allowed to identify the induction of proteins related to processes such as energy production, glutathione metabolism as well as accumulation of HSPs. In addition, the inter-strain comparison of stress-related proteomes led to identify features related to copper tolerance in Es524, such as striking expression of a PSII Mn-stabilizing protein and a Fucoxanthine chlorophyll a-c binding protein. Es524 also expressed specific stress-related enzymes such as RNA helicases from the DEAD box families and a vanadium-dependent bromoperoxidase. These observations were supported by RT-qPCR for some of the identified genes and an enzyme activity assay for vanadium-dependent bromoperoxidase. Therefore, the occurrence of two different phenotypes within two distinct E. siliculosus strains studied at the physiological and proteomic levels strongly suggest that persistent copper stress may represent a selective force leading to the development of strains genetically adapted to copper contaminated sites.
Collapse
Affiliation(s)
- Andrés Ritter
- Université Pierre et Marie Curie-Paris 6, Végétaux Marins et Biomolécules, Station Biologique, Place Georges Teissier, Roscoff, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|