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Montuori E, De Luca D, Penna A, Stalberga D, Lauritano C. Alexandrium spp.: From Toxicity to Potential Biotechnological Benefits. Mar Drugs 2023; 22:31. [PMID: 38248656 PMCID: PMC10821459 DOI: 10.3390/md22010031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 12/27/2023] [Accepted: 12/28/2023] [Indexed: 01/23/2024] Open
Abstract
Many dinoflagellates of the genus Alexandrium are well known for being responsible for harmful algal blooms (HABs), producing potent toxins that cause damages to other marine organisms, aquaculture, fishery, tourism, as well as induce human intoxications and even death after consumption of contaminated shellfish or fish. In this review, we summarize potential bioprospecting associated to the genus Alexandrium, including which Alexandrium spp. produce metabolites with anticancer, antimicrobial, antiviral, as well as anti-Alzheimer applications. When available, we report their mechanisms of action and targets. We also discuss recent progress on the identification of secondary metabolites with biological properties favorable to human health and aquaculture. Altogether, this information highlights the importance of studying which culturing conditions induce the activation of enzymatic pathways responsible for the synthesis of bioactive metabolites. It also suggests considering and comparing clones collected in different locations for toxin monitoring and marine bioprospecting. This review can be of interest not only for the scientific community, but also for the entire population and industries.
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Affiliation(s)
- Eleonora Montuori
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno d’Alcontres 31, 98166 Messina, Italy;
- Department of Ecosustainable Marine Biotechnology, Stazione Zoologica Anton Dohrn, Via Acton 55, 80133 Napoli, Italy
| | - Daniele De Luca
- Research Infrastructure for Marine Biological Resources Department, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy;
| | - Antonella Penna
- Department of Biomolecular Sciences, University of Urbino, Campus E. Mattei, 61029 Urbino, Italy;
| | - Darta Stalberga
- Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology, Linköping University, SE-58183 Linköping, Sweden;
| | - Chiara Lauritano
- Department of Ecosustainable Marine Biotechnology, Stazione Zoologica Anton Dohrn, Via Acton 55, 80133 Napoli, Italy
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2
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Weiner AKM, Sehein T, Cote-L’Heureux A, Sleith RS, Greco M, Malekshahi C, Ryan-Embry C, Ostriker N, Katz LA. Single-cell transcriptomics supports presence of cryptic species and reveals low levels of population genetic diversity in two testate amoebae morphospecies with large population sizes. Evolution 2023; 77:2472-2483. [PMID: 37672006 PMCID: PMC10629589 DOI: 10.1093/evolut/qpad158] [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: 08/03/2022] [Revised: 08/13/2023] [Accepted: 09/05/2023] [Indexed: 09/07/2023]
Abstract
The enormous population sizes and wide biogeographical distribution of many microbial eukaryotes set the expectation of high levels of intraspecific genetic variation. However, studies investigating protist populations remain scarce, mostly due to limited 'omics data. Instead, most genetics studies of microeukaryotes have thus far relied on single loci, which can be misleading and do not easily allow for detection of recombination, a hallmark of sexual reproduction. Here, we analyze >40 genes from 72 single-cell transcriptomes from two morphospecies-Hyalosphenia papilio and Hyalosphenia elegans-of testate amoebae (Arcellinida, Amoebozoa) to assess genetic diversity in samples collected over four years from New England bogs. We confirm the existence of cryptic species based on our multilocus dataset, which provides evidence of recombination within and high levels of divergence between the cryptic species. At the same time, total levels of genetic diversity within cryptic species are low, suggesting that these abundant organisms have small effective population sizes, perhaps due to extinction and repopulation events coupled with efficient modes of dispersal. This study is one of the first to investigate population genetics in uncultivable heterotrophic protists using transcriptomics data and contributes towards understanding cryptic species of nonmodel microeukaryotes.
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Affiliation(s)
- Agnes K M Weiner
- Department of Biological Sciences, Smith College, Northampton, MA, United States
- NORCE Climate and Environment, NORCE Norwegian Research Centre AS, Bergen, Norway
| | - Taylor Sehein
- Department of Biological Sciences, Smith College, Northampton, MA, United States
| | - Auden Cote-L’Heureux
- Department of Biological Sciences, Smith College, Northampton, MA, United States
| | - Robin S Sleith
- Department of Biological Sciences, Smith College, Northampton, MA, United States
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States
| | - Mattia Greco
- Department of Biological Sciences, Smith College, Northampton, MA, United States
| | - Clara Malekshahi
- Department of Biological Sciences, Smith College, Northampton, MA, United States
| | - Chase Ryan-Embry
- Department of Biological Sciences, Smith College, Northampton, MA, United States
| | - Naomi Ostriker
- Department of Biological Sciences, Smith College, Northampton, MA, United States
| | - Laura A Katz
- Department of Biological Sciences, Smith College, Northampton, MA, United States
- University of Massachusetts Amherst, Program in Organismic and Evolutionary Biology, Amherst, MA, United States
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3
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Borges FO, Lopes VM, Santos CF, Costa PR, Rosa R. Impacts of Climate Change on the Biogeography of Three Amnesic Shellfish Toxin Producing Diatom Species. Toxins (Basel) 2022; 15:9. [PMID: 36668829 PMCID: PMC9863508 DOI: 10.3390/toxins15010009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Harmful algal blooms (HABs) are considered one of the main risks for marine ecosystems and human health worldwide. Climate change is projected to induce significant changes in species geographic distribution, and, in this sense, it is paramount to accurately predict how it will affect toxin-producing microalgae. In this context, the present study was intended to project the potential biogeographical changes in habitat suitability and occurrence distribution of three key amnesic shellfish toxin (AST)-producing diatom species (i.e., Pseudo-nitzschia australis, P. seriata, and P. fraudulenta) under four different climate change scenarios (i.e., RCP-2.6, 4.5, 6.0, and 8.5) up to 2050 and 2100. For this purpose, we applied species distribution models (SDMs) using four abiotic predictors (i.e., sea surface temperature, salinity, current velocity, and bathymetry) in a MaxEnt framework. Overall, considerable contraction and potential extirpation were projected for all species at lower latitudes together with projected poleward expansions into higher latitudes, mainly in the northern hemisphere. The present study aims to contribute to the knowledge on the impacts of climate change on the biogeography of toxin-producing microalgae species while at the same time advising the correct environmental management of coastal habitats and ecosystems.
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Affiliation(s)
- Francisco O. Borges
- MARE—Marine and Environmental Sciences Centre & ARNET—Aquatic Research Network, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Vanessa M. Lopes
- MARE—Marine and Environmental Sciences Centre & ARNET—Aquatic Research Network, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Catarina Frazão Santos
- MARE—Marine and Environmental Sciences Centre & ARNET—Aquatic Research Network, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Pedro Reis Costa
- IPMA—Portuguese Institute for the Sea and Atmosphere, 1749-077 Lisboa, Portugal
- S2AQUA—Collaborative Laboratory, Association for a Sustainable and Smart Aquaculture, 8700-194 Olhão, Portugal
- CCMAR—Centre of Marine Sciences, Campus de Gambelas, University of Algarve, 8005-139 Faro, Portugal
| | - Rui Rosa
- MARE—Marine and Environmental Sciences Centre & ARNET—Aquatic Research Network, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
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4
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Da Silva O, Ayata SD, Ser-Giacomi E, Leconte J, Pelletier E, Fauvelot C, Madoui MA, Guidi L, Lombard F, Bittner L. Genomic differentiation of three pico-phytoplankton species in the Mediterranean Sea. Environ Microbiol 2022; 24:6086-6099. [PMID: 36053818 PMCID: PMC10087736 DOI: 10.1111/1462-2920.16171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 08/09/2022] [Indexed: 01/12/2023]
Abstract
For more than a decade, high-throughput sequencing has transformed the study of marine planktonic communities and has highlighted the extent of protist diversity in these ecosystems. Nevertheless, little is known relative to their genomic diversity at the species-scale as well as their major speciation mechanisms. An increasing number of data obtained from global scale sampling campaigns is becoming publicly available, and we postulate that metagenomic data could contribute to deciphering the processes shaping protist genomic differentiation in the marine realm. As a proof of concept, we developed a findable, accessible, interoperable and reusable (FAIR) pipeline and focused on the Mediterranean Sea to study three a priori abundant protist species: Bathycoccus prasinos, Pelagomonas calceolata and Phaeocystis cordata. We compared the genomic differentiation of each species in light of geographic, environmental and oceanographic distances. We highlighted that isolation-by-environment shapes the genomic differentiation of B. prasinos, whereas P. cordata is impacted by geographic distance (i.e. isolation-by-distance). At present time, the use of metagenomics to accurately estimate the genomic differentiation of protists remains challenging since coverages are lower compared to traditional population surveys. However, our approach sheds light on ecological and evolutionary processes occurring within natural marine populations and paves the way for future protist population metagenomic studies.
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Affiliation(s)
- Ophélie Da Silva
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, LOV, Villefranche-sur-Mer, France.,Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, Paris, France
| | - Sakina-Dorothée Ayata
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, LOV, Villefranche-sur-Mer, France.,Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, Paris, France.,Sorbonne Université, UMR 7159 CNRS-IRD-MNHN, LOCEAN-IPSL, Paris, France
| | - Enrico Ser-Giacomi
- Sorbonne Université, UMR 7159 CNRS-IRD-MNHN, LOCEAN-IPSL, Paris, France.,Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Jade Leconte
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France
| | - Eric Pelletier
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, Paris, France
| | - Cécile Fauvelot
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, LOV, Villefranche-sur-Mer, France.,Institut de Recherche pour le Développement (IRD), UMR ENTROPIE, Nouméa, New Caledonia
| | - Mohammed-Amin Madoui
- Service d'Etude des Prions et des Infections Atypiques (SEPIA), Institut François Jacob, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Université Paris Saclay, Fontenay-aux-Roses, France
| | - Lionel Guidi
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, LOV, Villefranche-sur-Mer, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, Paris, France
| | - Fabien Lombard
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, LOV, Villefranche-sur-Mer, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, Paris, France.,Institut Universitaire de France (IUF), Paris, France
| | - Lucie Bittner
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, Paris, France.,Institut Universitaire de France (IUF), Paris, France
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5
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Le Gac M, Mary L, Metegnier G, Quéré J, Siano R, Rodríguez F, Destombe C, Sourisseau M. Strong population genomic structure of the toxic dinoflagellate Alexandrium minutum inferred from meta-transcriptome samples. Environ Microbiol 2022; 24:5966-5983. [PMID: 36302091 DOI: 10.1111/1462-2920.16257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 10/20/2022] [Indexed: 01/12/2023]
Abstract
Despite theoretical expectations, marine microeukaryote population are often highly structured and the mechanisms behind such patterns remain to be elucidated. These organisms display huge census population sizes, yet genotyping usually requires clonal strains originating from single cells, hindering proper population sampling. Estimating allelic frequency directly from population wide samples, without any isolation step, offers an interesting alternative. Here, we validate the use of meta-transcriptome environmental samples to determine the population genetic structure of the dinoflagellate Alexandrium minutum. Strain and meta-transcriptome based results both indicated a strong genetic structure for A. minutum in Western Europe, to the level expected between cryptic species. The presence of numerous private alleles, and even fixed polymorphism, would indicate ancient divergence and absence of gene flow between populations. Single nucleotide polymorphisms (SNPs) displaying strong allele frequency differences were distributed throughout the genome, which might indicate pervasive selection from standing genetic variation (soft selective sweeps). However, a few genomic regions displayed extremely low diversity that could result from the fixation of adaptive de novo mutations (hard selective sweeps) within the populations.
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Affiliation(s)
| | - Lou Mary
- Ifremer, Dyneco, Plouzané, France
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6
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Projecting Future Climate Change-Mediated Impacts in Three Paralytic Shellfish Toxins-Producing Dinoflagellate Species. BIOLOGY 2022; 11:biology11101424. [PMID: 36290328 PMCID: PMC9598431 DOI: 10.3390/biology11101424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/26/2022] [Accepted: 09/27/2022] [Indexed: 11/19/2022]
Abstract
Simple Summary Harmful algal blooms present a particular risk for marine ecosystems and human health alike. In this sense, it is important to accurately predict how toxin-producing microalgae could be affected by future climate change. The present study applied species distribution models (SDMs) to project the potential changes in the habitat suitability and distribution of three key paralytic shellfish toxin (PST)-producing dinoflagellate species (i.e., Alexandrium catenella, A. minutum, and Gymnodinium catenatum), up to 2040/50 and 2090/2100, across four different greenhouse gas emission scenarios, and using four abiotic predictors (i.e., sea surface temperature, salinity, current velocity, and bathymetry). In general, considerable contractions were observed for all three species in the lower latitudes of their distribution, together with projected expansions into higher latitudes, particularly in the Northern Hemisphere. This study aims to entice further research on the future biogeographical impacts of climate change in toxin-producing microalgae species while, at the same time, helping to advise the correct environmental management of coastal habitats and ecosystems. Abstract Toxin-producing microalgae present a significant environmental risk for ecosystems and human societies when they reach concentrations that affect other aquatic organisms or human health. Harmful algal blooms (HAB) have been linked to mass wildlife die-offs and human food poisoning episodes, and climate change has the potential to alter the frequency, magnitude, and geographical extent of such events. Thus, a framework of species distribution models (SDMs), employing MaxEnt modeling, was used to project changes in habitat suitability and distribution of three key paralytic shellfish toxin (PST)-producing dinoflagellate species (i.e., Alexandrium catenella, A. minutum, and Gymnodinium catenatum), up to 2050 and 2100, across four representative concentration pathway scenarios (RCP-2.6, 4.5, 6.0, and 8.5; CMIP5). Despite slightly different responses at the regional level, the global habitat suitability has decreased for all the species, leading to an overall contraction in their tropical and sub-tropical ranges, while considerable expansions are projected in higher latitudes, particularly in the Northern Hemisphere, suggesting poleward distributional shifts. Such trends were exacerbated with increasing RCP severity. Yet, further research is required, with a greater assemblage of environmental predictors and improved occurrence datasets, to gain a more holistic understanding of the potential impacts of climate change on PST-producing species.
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7
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Verma A, Hughes DJ, Harwood DT, Suggett DJ, Ralph PJ, Murray SA. Functional significance of phylogeographic structure in a toxic benthic marine microbial eukaryote over a latitudinal gradient along the East Australian Current. Ecol Evol 2020; 10:6257-6273. [PMID: 32724512 PMCID: PMC7381561 DOI: 10.1002/ece3.6358] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 03/24/2020] [Accepted: 04/22/2020] [Indexed: 01/04/2023] Open
Abstract
Genetic diversity in marine microbial eukaryotic populations (protists) drives their ecological success by enabling diverse phenotypes to respond rapidly to changing environmental conditions. Despite enormous population sizes and lack of barriers to gene flow, genetic differentiation that is associated with geographic distance, currents, and environmental gradients has been reported from planktonic protists. However, for benthic protists, which have reduced dispersal opportunities, phylogeography and its phenotypic significance are little known. In recent years, the East Australian Current (EAC) has intensified its southward flow, associated with the tropicalization of temperate waters. Benthic harmful algal species have been increasingly found in south-eastern Australia. Yet little is known about the potential of these species to adapt or extend their range in relation to changing conditions. Here, we examine genetic diversity and functional niche divergence in a toxic benthic dinoflagellate, Ostreopsis cf. siamensis, along a 1,500 km north-south gradient in southeastern Australia. Sixty-eight strains were established from eight sampling sites. The study revealed long-standing genetic diversity among strains established from the northern-most sites, along with large phenotypic variation in observed physiological traits such as growth rates, cell volume, production of palytoxin-like compounds, and photophysiological parameters. Strains from the southern populations were more uniform in both genetic and functional traits, and have possibly colonized their habitats more recently. Our study reports significant genetic and functional trait variability in a benthic harmful algal species, indicative of high adaptability, and a possible climate-driven range extension. The observed high trait variation may facilitate development of harmful algal blooms under dynamic coastal environmental conditions.
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Affiliation(s)
- Arjun Verma
- Climate Change ClusterUniversity of Technology SydneyUltimoNSWAustralia
| | - David J. Hughes
- Climate Change ClusterUniversity of Technology SydneyUltimoNSWAustralia
| | | | - David J. Suggett
- Climate Change ClusterUniversity of Technology SydneyUltimoNSWAustralia
| | - Peter J. Ralph
- Climate Change ClusterUniversity of Technology SydneyUltimoNSWAustralia
| | - Shauna A. Murray
- Climate Change ClusterUniversity of Technology SydneyUltimoNSWAustralia
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8
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Branco S, Oliveira MMM, Salgueiro F, Vilar MCP, Azevedo SMFO, Menezes M. Morphology and molecular phylogeny of a new PST-producing dinoflagellate species: Alexandrium fragae sp. nov. (Gonyaulacales, dinophyceae). HARMFUL ALGAE 2020; 95:101793. [PMID: 32439062 DOI: 10.1016/j.hal.2020.101793] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/27/2020] [Accepted: 03/01/2020] [Indexed: 06/11/2023]
Abstract
The genus Alexandrium comprises some of the most potentially toxic marine algae. A new toxic species of Alexandrium, A. fragae sp. nov., was found in Guanabara Bay, Rio de Janeiro, southern Brazil. The new species produces GTX2&3 and STX. The cell morphology of A. fragae resembles A. minutum in many characters, including the small size; the rounded-elliptical shape; and the shapes of the apical pore complex (APC), first apical plate (1'), sixth precingular plate (6″), and anterior and posterior sulcal plates (s.a. and s.p.). The main diagnostic characters of A. fragae are the ornamentation pattern, smooth epitheca and reticulated hypotheca, all of which were present in both natural populations and cultures. Phylogenies inferred from the ITS, LSU, and SSU rDNA of A. fragae showed that A. fragae clustered in a well-supported clade, distinct from other Alexandrium species. Morphology and molecular analyses based on ITS and LSU rDNA indicated that A. fragae strains and Alexandrium sp. from Japan (D163C5, D164C6) are a single species. Our findings suggest that the Alexandrium morphotype with a smooth epitheca and reticulated hypotheca, previously identified as A. minutum in different geographic regions, may corresponds to A. fragae.
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Affiliation(s)
- Suema Branco
- Laboratório de Ficologia, Departamento de Botânica, Museu Nacional / Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, s/no, São Cristóvão, 20940-040 Rio de Janeiro, Brazil.
| | - Mair M M Oliveira
- Laboratório de Biomineralização, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Cidade Universitária, 21941-590 Rio de Janeiro, Brazil
| | - Fabiano Salgueiro
- Laboratório de Biodiversidade e Evolução Molecular, Universidade Federal do Estado do Rio de Janeiro, Av. Pasteur 458, sala 512, Urca, 22290-240 Rio de Janeiro, Brazil
| | - Mauro C P Vilar
- Laboratório de Ecofisiologia e Toxicologia de Cianobactérias, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21949-902 Rio de Janeiro, Brazil
| | - Sandra M F O Azevedo
- Laboratório de Ecofisiologia e Toxicologia de Cianobactérias, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, 21949-902 Rio de Janeiro, Brazil
| | - Mariângela Menezes
- Laboratório de Ficologia, Departamento de Botânica, Museu Nacional / Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, s/no, São Cristóvão, 20940-040 Rio de Janeiro, Brazil
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9
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Turk Dermastia T, Cerino F, Stanković D, Francé J, Ramšak A, Žnidarič Tušek M, Beran A, Natali V, Cabrini M, Mozetič P. Ecological time series and integrative taxonomy unveil seasonality and diversity of the toxic diatom Pseudo-nitzschia H. Peragallo in the northern Adriatic Sea. HARMFUL ALGAE 2020; 93:101773. [PMID: 32307066 DOI: 10.1016/j.hal.2020.101773] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 01/06/2020] [Accepted: 02/03/2020] [Indexed: 06/11/2023]
Abstract
Pseudo-nitzschia H. Peragallo (1900) is a globally distributed genus of pennate diatoms that are important components of phytoplankton communities worldwide. Some members of the genus produce the neurotoxin domoic acid, so regular monitoring is in place. However, the identification of toxic members in routine samplings remains problematic. In this study, the diversity and seasonal occurrence of Pseudo-nitzschia species were investigated in the Gulf of Trieste, a shallow gulf in the northern Adriatic Sea. We used time series data from 2005 to 2018 to describe the seasonal and inter-annual occurrence of the genus in the area and its contribution to the phytoplankton community. On average, the genus accounted for about 15 % of total diatom abundance and peaked in spring and autumn, with occasional outbreaks during summer and large inter-annual fluctuations. Increased water temperature and decreased salinity positively affected the presence of some members of the genus, while strong effects could be masked by an unsuitable definition of the species complexes used for monitoring purposes. Therefore, combining morphological (TEM) and molecular analyses by sequencing the ITS, 28S and rbcL markers, eight species were identified from 83 isolated monoclonal strains: P. calliantha, P. fraudulenta, P. delicatissima, P. galaxiae, P. mannii, P. multistriata, P. pungens and P. subfraudulenta. A genetic comparison between the isolated strains and other strains in the Mediterranean was carried out and rbcL was inspected as a potential barcode marker in respect to our results. This is the first study in the Gulf of Trieste on Pseudo-nitzschia time series from a long-term ecological research (LTER) site coupled with molecular data. We show that meaningful ecological conclusions can be drawn by applying integrative methodology, as opposed to the approach that only considers species complexes. The results of this work will provide guidance for further monitoring efforts as well as research activities, including population genetics and genomics, associated with seasonal distribution and toxicity profiles.
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Affiliation(s)
- Timotej Turk Dermastia
- National Institute of Biology, Marine Biology Station Piran, Fornače 41, 6330 Piran, Slovenia; International Postgraduate School Jožef Stefan, Jamova cesta 39, 1000 Ljubljana, Slovenia.
| | - Federica Cerino
- Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, via Piccard 54, 34151 Trieste, Italy
| | - David Stanković
- National Institute of Biology, Marine Biology Station Piran, Fornače 41, 6330 Piran, Slovenia
| | - Janja Francé
- National Institute of Biology, Marine Biology Station Piran, Fornače 41, 6330 Piran, Slovenia
| | - Andreja Ramšak
- National Institute of Biology, Marine Biology Station Piran, Fornače 41, 6330 Piran, Slovenia
| | - Magda Žnidarič Tušek
- National Institute of Biology, Department of Biotechnology and Systems Biology, Večna pot 111, 1000 Ljubljana, Slovenia
| | - Alfred Beran
- Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, via Piccard 54, 34151 Trieste, Italy
| | - Vanessa Natali
- Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, via Piccard 54, 34151 Trieste, Italy
| | - Marina Cabrini
- Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, via Piccard 54, 34151 Trieste, Italy
| | - Patricija Mozetič
- National Institute of Biology, Marine Biology Station Piran, Fornače 41, 6330 Piran, Slovenia
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10
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Population co-divergence in common cuttlefish (Sepia officinalis) and its dicyemid parasite in the Mediterranean Sea. Sci Rep 2019; 9:14300. [PMID: 31586090 PMCID: PMC6778094 DOI: 10.1038/s41598-019-50555-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 09/12/2019] [Indexed: 12/22/2022] Open
Abstract
Population structure and biogeography of marine organisms are formed by different drivers than in terrestrial organisms. Yet, very little information is available even for common marine organisms and even less for their associated parasites. Here we report the first analysis of population structure of both a cephalopod host (Sepia officinalis) and its dicyemid parasite, based on a homologous molecular marker (cytochrome oxidase I). We show that the population of common cuttlefish in the Mediterranean area is fragmented into subpopulations, with some areas featuring restricted level of gene flow. Amongst the studied areas, Sardinia was genetically the most diverse and Cyprus the most isolated. At a larger scale, across the Mediterranean, the population structure of the parasite shows co-diversification pattern with its host, but a slower rate of diversification. Differences between the two counterparts are more obvious at a finer scale, where parasite populations show increased level of fragmentation and lower local diversities. This discrepancy can be caused by local extinctions and replacements taking place more frequently in the dicyemid populations, due to their parasitic lifestyle.
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11
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Gao Y, Sassenhagen I, Richlen ML, Anderson DM, Martin JL, Erdner DL. Spatiotemporal genetic structure of regional-scale Alexandrium catenella dinoflagellate blooms explained by extensive dispersal and environmental selection. HARMFUL ALGAE 2019; 86:46-54. [PMID: 31358276 PMCID: PMC6668924 DOI: 10.1016/j.hal.2019.03.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 03/25/2019] [Accepted: 03/27/2019] [Indexed: 05/15/2023]
Abstract
Paralytic Shellfish Poisoning (PSP) caused by the dinoflagellate Alexandrium catenella is a well-known global syndrome that negatively impacts human health and fishery economies. Understanding the population dynamics and ecology of this species is thus important for identifying determinants of blooms and associated PSP toxicity. Given reports of extensive genetic heterogeneity in the toxicity and physiology of Alexandrium species, knowledge of genetic population structure in harmful algal species such as A. catenella can also facilitate the understanding of toxic bloom development and ecological adaptation. In this study we employed microsatellite markers to analyze multiple A. catenella strains isolated from several sub-regions in the Gulf of Maine (GoM) during summer blooms, to gain insights into the sources and dynamics of this economically important phytoplankton species. At least three genetically distinct clusters of A. catenella were identified in the GoM. Each cluster contained representatives from different sub-regions, highlighting the extent of connectivity and dispersal throughout the region. This shared diversity could result from cyst beds created by previous coastal blooms, thereby preserving the overall diversity of the regional A. catenella population. Rapid spatiotemporal genetic differentiation of A. catenella populations was observed in local blooms, likely driven by natural selection through environmental conditions such as silicate and nitrate/nitrite concentrations, emphasizing the role of short-term water mass intrusions and biotic processes in determining the diversity and dynamics of marine phytoplankton populations. Given the wide-spread intraspecific diversity of A. catenella in GoM and potentially elsewhere, harmful algal blooms will likely persist in many regions despite global warming and changing environmental conditions in the future. Selection of different genetic lineages through variable hydrological conditions might impact toxin production and profiles of future blooms, challenging HAB control and prediction of PSP risk in the future.
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Affiliation(s)
- Yida Gao
- Marine Science Institute, University of Texas at Austin, Port Aransas, TX, 78373, USA
| | - Ingrid Sassenhagen
- Marine Science Institute, University of Texas at Austin, Port Aransas, TX, 78373, USA; Laboratoire d'Océanologie et des Geosciences, UMR LOG 8187, Université du Littoral Côte d'Opale, Wimereux, France
| | - Mindy L Richlen
- Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | | | - Jennifer L Martin
- Fisheries and Oceans Canada, Biological Station, St. Andrews, NB, E5B 0E4, Canada
| | - Deana L Erdner
- Marine Science Institute, University of Texas at Austin, Port Aransas, TX, 78373, USA.
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12
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Lewis AM, Coates LN, Turner AD, Percy L, Lewis J. A review of the global distribution of Alexandrium minutum (Dinophyceae) and comments on ecology and associated paralytic shellfish toxin profiles, with a focus on Northern Europe. JOURNAL OF PHYCOLOGY 2018; 54:581-598. [PMID: 30047623 DOI: 10.1111/jpy.12768] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 06/21/2018] [Indexed: 06/08/2023]
Abstract
Alexandrium minutum is a globally distributed harmful algal bloom species with many strains that are known to produce paralytic shellfish toxins (PSTs) and consequently represent a concern to human and ecosystem health. This review highlights that A. minutum typically occurs in sheltered locations, with cell growth occurring during periods of stable water conditions. Sediment characteristics are important in the persistence of this species within a location, with fine sediments providing cyst deposits for ongoing inoculation to the water column. Toxic strains of A. minutum do not produce a consistent toxin profile, different populations produce a range of PSTs in differing quantities. Novel cluster analysis of published A. minutum toxin profiles indicates five PST profile clusters globally. Some clusters are grouped geographically (Northern Europe) while others are widely spread. Isolates from Taiwan have a range of toxin profile clusters and this area appears to have the most diverse set of PST producing A. minutum populations. These toxin profiles indicate that within the United Kingdom there are two populations of A. minutum grouping with strains from Northern France and Southern Ireland. There is a degree of interconnectivity in this region due to oceanic circulation and a high level of shipping and recreational boating. Further research into the interrelationships between the A. minutum populations in this global region would be of value.
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Affiliation(s)
- Adam Michael Lewis
- Cefas, The Nothe, Barrack Road, Weymouth, Dorset, DT48UB, UK
- Faculty of Science and Technology, The University of Westminster, 115 New Cavendish Street, London, W1W6UW, UK
| | | | - Andrew D Turner
- Cefas, The Nothe, Barrack Road, Weymouth, Dorset, DT48UB, UK
| | - Linda Percy
- Faculty of Science and Technology, The University of Westminster, 115 New Cavendish Street, London, W1W6UW, UK
| | - Jane Lewis
- Faculty of Science and Technology, The University of Westminster, 115 New Cavendish Street, London, W1W6UW, UK
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13
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Sundqvist L, Godhe A, Jonsson PR, Sefbom J. The anchoring effect-long-term dormancy and genetic population structure. ISME JOURNAL 2018; 12:2929-2941. [PMID: 30068937 DOI: 10.1038/s41396-018-0216-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 05/18/2018] [Accepted: 06/11/2018] [Indexed: 11/09/2022]
Abstract
Understanding the genetic structure of populations is key to revealing past and present demographic and evolutionary processes in a species. In the past decade high genetic differentiation has been observed in many microbial species challenging the previous view of cosmopolitan distribution. Populations have displayed high genetic differentiation, even at small spatial scales, despite apparent high dispersal. Numerous species of microalgae have a life-history strategy that includes a long-term resting stage, which can accumulate in sediments and serve as refuge during adverse conditions. It is presently unclear how these seed banks affect the genetic structure of populations in aquatic environments. Here we provide a conceptual framework, using a simple model, to show that long-term resting stages have an anchoring effect on populations leading to increased genetic diversity and population differentiation in the presence of gene flow. The outcome that species with resting stages have a higher degree of genetic differentiation compared to species without, is supported by empirical data obtained from a systematic literature review. With this work we propose that seed banks in aquatic microalgae play an important role in the contradicting patterns of gene flow, and ultimately the adaptive potential and population dynamics in species with long-term resting stages.
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Affiliation(s)
- Lisa Sundqvist
- Department of Marine Sciences, University of Gothenburg, Box 461, Göteborg, SE, 40530, Sweden
| | - Anna Godhe
- Department of Marine Sciences, University of Gothenburg, Box 461, Göteborg, SE, 40530, Sweden
| | - Per R Jonsson
- Department of Marine Sciences - Tjärnö, University of Gothenburg, Strömstad, SE, 45296, Sweden
| | - Josefin Sefbom
- Department of Marine Sciences, University of Gothenburg, Box 461, Göteborg, SE, 40530, Sweden. .,Department of Biology, Laboratory of Protistology and Aquatic Ecology, Ghent University, Krijgslaan 281-S8, Gent, B-9000, Belgium.
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14
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Sefbom J, Kremp A, Rengefors K, Jonsson PR, Sjöqvist C, Godhe A. A planktonic diatom displays genetic structure over small spatial scales. Environ Microbiol 2018; 20:2783-2795. [PMID: 29614214 DOI: 10.1111/1462-2920.14117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 03/22/2018] [Indexed: 11/30/2022]
Abstract
Marine planktonic microalgae have potentially global dispersal, yet reduced gene flow has been confirmed repeatedly for several species. Over larger distances (>200 km) geographic isolation and restricted oceanographic connectivity have been recognized as instrumental in driving population divergence. Here we investigated whether similar patterns, that is, structured populations governed by geographic isolation and/or oceanographic connectivity, can be observed at smaller (6-152 km) geographic scales. To test this we established 425 clonal cultures of the planktonic diatom Skeletonema marinoi collected from 11 locations in the Archipelago Sea (northern Baltic Sea). The region is characterized by a complex topography, entailing several mixing regions of which four were included in the sampling area. Using eight microsatellite markers and conventional F-statistics, significant genetic differentiation was observed between several sites. Moreover, Bayesian cluster analysis revealed the co-occurrence of two genetic groups spread throughout the area. However, geographic isolation and oceanographic connectivity could not explain the genetic patterns observed. Our data reveal hierarchical genetic structuring whereby despite high dispersal potential, significantly diverged populations have developed over small spatial scales. Our results suggest that biological characteristics and historical events may be more important in generating barriers to gene flow than physical barriers at small spatial scales.
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Affiliation(s)
- Josefin Sefbom
- Department of Marine Sciences, University of Gothenburg, Gothenberg, Sweden
| | - Anke Kremp
- Marine Research Centre, Finnish Environment Institute (SYKE), Helsinki, Finland
| | - Karin Rengefors
- Aquatic Ecology, Department of Biology, Lund University, Lund, Sweden
| | - Per R Jonsson
- Department of Marine Sciences-Tjärnö, University of Gothenburg, Gothenberg, Sweden
| | - Conny Sjöqvist
- Marine Research Centre, Finnish Environment Institute (SYKE), Helsinki, Finland.,Environmental and Marine Biology, Åbo Akademi University, Åbo, Finland
| | - Anna Godhe
- Department of Marine Sciences, University of Gothenburg, Gothenberg, Sweden
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15
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Fernández LD, Hernández CE, Schiaffino MR, Izaguirre I, Lara E. Geographical distance and local environmental conditions drive the genetic population structure of a freshwater microalga (Bathycoccaceae; Chlorophyta) in Patagonian lakes. FEMS Microbiol Ecol 2017; 93:4331630. [DOI: 10.1093/femsec/fix125] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 09/26/2017] [Indexed: 01/26/2023] Open
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16
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Le Gac M, Metegnier G, Chomérat N, Malestroit P, Quéré J, Bouchez O, Siano R, Destombe C, Guillou L, Chapelle A. Evolutionary processes and cellular functions underlying divergence in Alexandrium minutum. Mol Ecol 2016; 25:5129-5143. [DOI: 10.1111/mec.13815] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 08/04/2016] [Accepted: 08/04/2016] [Indexed: 01/07/2023]
Affiliation(s)
| | - Gabriel Metegnier
- Ifremer; DYNECO PELAGOS; 29280 Plouzané France
- CNRS, PUCCh, UACH, UMI 3614; Evolutionary Biology and Ecology of Algae; Station Biologique de Roscoff; Université Pierre et Marie Curie - Paris 6; Sorbonne Universités; Place Georges Teissier, CS90074 29688 Roscoff Cedex France
| | | | | | | | - Olivier Bouchez
- GeT PlaGe; Genotoul; INRA Auzeville; Castanet Tolosan France
| | | | - Christophe Destombe
- CNRS, PUCCh, UACH, UMI 3614; Evolutionary Biology and Ecology of Algae; Station Biologique de Roscoff; Université Pierre et Marie Curie - Paris 6; Sorbonne Universités; Place Georges Teissier, CS90074 29688 Roscoff Cedex France
| | - Laure Guillou
- CNRS, UMR 7144; Station Biologique de Roscoff; Université Pierre et Marie Curie - Paris 6; Sorbonne Universités; Place Georges Teissier CS90074 29688 Roscoff Cedex France
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17
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Sildever S, Sefbom J, Lips I, Godhe A. Competitive advantage and higher fitness in native populations of genetically structured planktonic diatoms. Environ Microbiol 2016; 18:4403-4411. [PMID: 27207672 DOI: 10.1111/1462-2920.13372] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 05/04/2016] [Indexed: 12/23/2022]
Abstract
It has been shown that the planktonic diatom Skeletonema from neighbouring areas are genetically differentiated despite absence of physical dispersal barriers. We revisited two sites, Mariager Fjord and Kattegat, NE Atlantic, and isolated new strains. Microsatellite genotyping and F-statistics revealed that the populations were genetically differentiated. An experiment was designed to investigate if populations are locally adapted and have a native competitive advantage. Ten strains from each location were grown individually in native and foreign water to investigate differences in produced biomass. Additionally, we mixed six pairs, one strain from each site, and let them grow together in native and foreign water. Strains from Mariager Fjord and Kattegat produced higher biomass in native water. In the competition experiment, strains from both sites displayed higher relative abundance and demonstrated competitive advantage in their native water. The cause of the differentiated growth is unknown, but could possibly be attributed to differences in silica concentration or viruses in the two water types. Our data show that dispersal potential does not influence the genetic structure of the populations. We conclude that genetic adaptation has not been overruled by gene flow, but instead the responses to different selection conditions are enforcing the observed genetic structure.
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Affiliation(s)
- Sirje Sildever
- Department of Marine Sciences, University of Gothenburg, Göteborg, Sweden.,Marine Systems Institute, Tallinn University of Technology, Tallinn, Estonia
| | - Josefin Sefbom
- Department of Marine Sciences, University of Gothenburg, Göteborg, Sweden
| | - Inga Lips
- Marine Systems Institute, Tallinn University of Technology, Tallinn, Estonia
| | - Anna Godhe
- Department of Marine Sciences, University of Gothenburg, Göteborg, Sweden
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18
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Penna A, Perini F, Dell'Aversano C, Capellacci S, Tartaglione L, Giacobbe MG, Casabianca S, Fraga S, Ciminiello P, Scardi M. The sxt Gene and Paralytic Shellfish Poisoning Toxins as Markers for the Monitoring of Toxic Alexandrium Species Blooms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:14230-14238. [PMID: 26580419 DOI: 10.1021/acs.est.5b03298] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Paralytic shellfish poisoning (PSP) is a serious human illness caused by the ingestion of seafood contaminated with saxitoxin and its derivatives (STXs). These toxins are produced by some species of marine dinoflagellates within the genus Alexandrium. In the Mediterranean Sea, toxic Alexandrium spp. blooms, especially of A. minutum, are frequent and intense with negative impact to coastal ecosystem, aquaculture practices and other economic activities. We conducted a large scale study on the sxt gene and toxin distribution and content in toxic dinoflagellate A. minutum of the Mediterranean Sea using both quantitative PCR (qPCR) and HILIC-HRMS techniques. We developed a new qPCR assay for the estimation of the sxtA1 gene copy number in seawater samples during a bloom event in Syracuse Bay (Mediterranean Sea) with an analytical sensitivity of 2.0 × 10° sxtA1 gene copy number per reaction. The linear correlation between sxtA1 gene copy number and microalgal abundance and between the sxtA1 gene and STX content allowed us to rapidly determine the STX-producing cell concentrations of two Alexandrium species in environmental samples. In these samples, the amount of sxtA1 gene was in the range of 1.38 × 10(5) - 2.55 × 10(8) copies/L and the STX concentrations ranged from 41-201 nmol/L. This study described a potential PSP scenario in the Mediterranean Sea.
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Affiliation(s)
- Antonella Penna
- Department of Biomolecular Sciences, University of Urbino , Pesaro, Italy
- Institute of Marine Sciences, ISMAR - CNR , Ancona, Italy
| | - Federico Perini
- Department of Biomolecular Sciences, University of Urbino , Pesaro, Italy
- Institute of Marine Sciences, ISMAR - CNR , Ancona, Italy
| | | | - Samuela Capellacci
- Department of Biomolecular Sciences, University of Urbino , Pesaro, Italy
| | | | | | - Silvia Casabianca
- Department of Biomolecular Sciences, University of Urbino , Pesaro, Italy
| | - Santiago Fraga
- Centro Oceanografico de Vigo, Instituto Espanol de Oceanografıa (IEO) , Vigo, Spain
| | | | - Michele Scardi
- Department of Biology, University of Tor Vergata , Rome, Italy
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19
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Sjöqvist C, Godhe A, Jonsson PR, Sundqvist L, Kremp A. Local adaptation and oceanographic connectivity patterns explain genetic differentiation of a marine diatom across the North Sea-Baltic Sea salinity gradient. Mol Ecol 2015; 24:2871-85. [PMID: 25892181 PMCID: PMC4692096 DOI: 10.1111/mec.13208] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 04/13/2015] [Accepted: 04/16/2015] [Indexed: 01/22/2023]
Abstract
Drivers of population genetic structure are still poorly understood in marine micro-organisms. We exploited the North Sea-Baltic Sea transition for investigating the seascape genetics of a marine diatom, Skeletonema marinoi. Eight polymorphic microsatellite loci were analysed in 354 individuals from ten locations to analyse population structure of the species along a 1500-km-long salinity gradient ranging from 3 to 30 psu. To test for salinity adaptation, salinity reaction norms were determined for sets of strains originating from three different salinity regimes of the gradient. Modelled oceanographic connectivity was compared to directional relative migration by correlation analyses to examine oceanographic drivers. Population genetic analyses showed distinct genetic divergence of a low-salinity Baltic Sea population and a high-salinity North Sea population, coinciding with the most evident physical dispersal barrier in the area, the Danish Straits. Baltic Sea populations displayed reduced genetic diversity compared to North Sea populations. Growth optima of low salinity isolates were significantly lower than those of strains from higher native salinities, indicating local salinity adaptation. Although the North Sea-Baltic Sea transition was identified as a barrier to gene flow, migration between Baltic Sea and North Sea populations occurred. However, the presence of differentiated neutral markers on each side of the transition zone suggests that migrants are maladapted. It is concluded that local salinity adaptation, supported by oceanographic connectivity patterns creating an asymmetric migration pattern between the Baltic Sea and the North Sea, determines genetic differentiation patterns in the transition zone.
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Affiliation(s)
- C Sjöqvist
- Environmental and Marine Biology, Åbo Akademi University, Artillerigatan 6, 20520, Åbo, Finland.,Finnish Environmental Institute/Marine Research Centre, PB 140, 00251, Helsinki, Finland
| | - A Godhe
- Department of Biological and Environmental Sciences, University of Gothenburg, PB 461, SE 40530, Göteborg, Sweden
| | - P R Jonsson
- Department of Biological and Environmental Sciences - Tjärnö, University of Gothenburg, SE 45296, Strömstad, Sweden
| | - L Sundqvist
- Department of Biological and Environmental Sciences, University of Gothenburg, PB 461, SE 40530, Göteborg, Sweden
| | - A Kremp
- Finnish Environmental Institute/Marine Research Centre, PB 140, 00251, Helsinki, Finland
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20
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Vanormelingen P, Evans KM, Mann DG, Lance S, Debeer AE, D'Hondt S, Verstraete T, De Meester L, Vyverman W. Genotypic diversity and differentiation among populations of two benthic freshwater diatoms as revealed by microsatellites. Mol Ecol 2015; 24:4433-48. [DOI: 10.1111/mec.13336] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 07/21/2015] [Accepted: 07/22/2015] [Indexed: 12/30/2022]
Affiliation(s)
- Pieter Vanormelingen
- Laboratory of Protistology and Aquatic Ecology; Ghent University; Krijgslaan 281 - S8 Gent 9000 Belgium
| | - Katharine M. Evans
- School of Geosciences; University of Edinburgh; Edinburgh EH9 3JW UK
- Royal Botanic Garden; Edinburgh EH3 5LR UK
| | - David G. Mann
- Royal Botanic Garden; Edinburgh EH3 5LR UK
- Aquatic Ecosystems; Institute for Food and Agricultural Research and Technology (IRTA); Crta de Poble Nou Km 5.5 E-43540 Sant Carles de la Ràpita Catalunya Spain
| | - Stacey Lance
- Savannah River Ecology Laboratory; University of Georgia; Aiken SC USA
| | - Ann-Eline Debeer
- Laboratory of Protistology and Aquatic Ecology; Ghent University; Krijgslaan 281 - S8 Gent 9000 Belgium
| | - Sofie D'Hondt
- Laboratory of Protistology and Aquatic Ecology; Ghent University; Krijgslaan 281 - S8 Gent 9000 Belgium
| | - Tine Verstraete
- Laboratory of Protistology and Aquatic Ecology; Ghent University; Krijgslaan 281 - S8 Gent 9000 Belgium
| | - Luc De Meester
- Laboratory of Aquatic Ecology, Evolution and Conservation; Katholieke Universiteit Leuven; Ch. De Bériotstraat 32 Leuven 3000 Belgium
| | - Wim Vyverman
- Laboratory of Protistology and Aquatic Ecology; Ghent University; Krijgslaan 281 - S8 Gent 9000 Belgium
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21
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Sassenhagen I, Sefbom J, Säll T, Godhe A, Rengefors K. Freshwater protists do not go with the flow: population structure in
G
onyostomum semen
independent of connectivity among lakes. Environ Microbiol 2015; 17:5063-72. [DOI: 10.1111/1462-2920.12987] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 07/14/2015] [Accepted: 07/14/2015] [Indexed: 01/08/2023]
Affiliation(s)
| | - Josefin Sefbom
- Department of Marine Sciences University of Gothenburg Box 461 Gothenburg 40530 Sweden
| | - Torbjörn Säll
- Evolutionary Genetics Lund University Sölvegatan 35 Lund 22362 Sweden
| | - Anna Godhe
- Department of Marine Sciences University of Gothenburg Box 461 Gothenburg 40530 Sweden
| | - Karin Rengefors
- Aquatic Ecology Lund University Sölvegatan 37 22362 Lund Sweden
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22
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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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23
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Tesson SVM, Montresor M, Procaccini G, Kooistra WHCF. Temporal changes in population structure of a marine planktonic diatom. PLoS One 2014; 9:e114984. [PMID: 25506926 PMCID: PMC4266644 DOI: 10.1371/journal.pone.0114984] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 11/17/2014] [Indexed: 01/17/2023] Open
Abstract
A prevailing question in phytoplankton research addresses changes of genetic diversity in the face of huge population sizes and apparently unlimited dispersal capabilities. We investigated population genetic structure of the pennate planktonic marine diatom Pseudo-nitzschia multistriata at the LTER station MareChiara in the Gulf of Naples (Italy) over four consecutive years and explored possible changes over seasons and from year to year. A total of 525 strains were genotyped using seven microsatellite markers, for a genotypic diversity of 75.05%, comparable to that found in other Pseudo-nitzschia species. Evidence from Bayesian clustering analysis (BA) identified two genetically distinct clusters, here interpreted as populations, and several strains that could not be assigned with ≥90% probability to either population, here interpreted as putative hybrids. Principal Component Analysis (PCA) recovered these two clusters in distinct clouds with most of the putative hybrids located in-between. Relative proportions of the two populations and the putative hybrids remained similar within years, but changed radically between 2008 and 2009 and between 2010 and 2011, when the 2008-population apparently became the dominant one again. Strains from the two populations are inter-fertile, and so is their offspring. Inclusion of genotypes of parental strains and their offspring shows that the majority of the latter could not be assigned to any of the two parental populations. Therefore, field strains classified by BA as the putative hybrids could be biological hybrids. We hypothesize that P. multistriata population dynamics in the Gulf of Naples follows a meta-population-like model, including establishment of populations by cell inocula at the beginning of each growth season and remixing and dispersal governed by moving and mildly turbulent water masses.
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Affiliation(s)
- Sylvie V. M. Tesson
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
- * E-mail:
| | - Marina Montresor
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
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24
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Perini F, Galluzzi L, Dell'Aversano C, Iacovo ED, Tartaglione L, Ricci F, Forino M, Ciminiello P, Penna A. SxtA and sxtG gene expression and toxin production in the Mediterranean Alexandrium minutum (Dinophyceae). Mar Drugs 2014; 12:5258-76. [PMID: 25341029 PMCID: PMC4210898 DOI: 10.3390/md12105258] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 09/23/2014] [Accepted: 10/15/2014] [Indexed: 01/18/2023] Open
Abstract
The dinoflagellate Alexandrium minutum is known for the production of potent neurotoxins affecting the health of human seafood consumers via paralytic shellfish poisoning (PSP). The aim of this study was to investigate the relationship between the toxin content and the expression level of the genes involved in paralytic shellfish toxin (PST) production. The algal cultures were grown both in standard f/2 medium and in phosphorus/nitrogen limitation. In our study, LC-HRMS analyses of PST profile and content in different Mediterranean A.minutum strains confirmed that this species was able to synthesize mainly the saxitoxin analogues Gonyautoxin-1 (GTX1) and Gonyautoxin-4 (GTX4). The average cellular toxin content varied among different strains, and between growth phases, highlighting a decreasing trend from exponential to stationary phase in all culture conditions tested. The absolute quantities of intracellular sxtA1 and sxtG mRNA were not correlated with the amount of intracellular toxins in the analysed A. minutum suggesting that the production of toxins may be regulated by post-transcriptional mechanisms and/or by the concerted actions of alternative genes belonging to the PST biosynthesis gene cluster. Therefore, it is likely that the sxtA1 and sxtG gene expression could not reflect the PST accumulation in the Mediterranean A. minutum populations under the examined standard and nutrient limiting conditions.
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Affiliation(s)
- Federico Perini
- Department of Biomolecular Sciences, University of Urbino, Viale Trieste 296, Pesaro 61121, Italy.
| | - Luca Galluzzi
- Department of Biomolecular Sciences, University of Urbino, Viale Trieste 296, Pesaro 61121, Italy.
| | - Carmela Dell'Aversano
- Department of Pharmacy, University of Naples Federico II, Via D. Montesano 49, Naples 80131, Italy.
| | - Emma Dello Iacovo
- Department of Pharmacy, University of Naples Federico II, Via D. Montesano 49, Naples 80131, Italy.
| | - Luciana Tartaglione
- Department of Pharmacy, University of Naples Federico II, Via D. Montesano 49, Naples 80131, Italy.
| | - Fabio Ricci
- Department of Biomolecular Sciences, University of Urbino, Viale Trieste 296, Pesaro 61121, Italy.
| | - Martino Forino
- Department of Pharmacy, University of Naples Federico II, Via D. Montesano 49, Naples 80131, Italy.
| | - Patrizia Ciminiello
- Department of Pharmacy, University of Naples Federico II, Via D. Montesano 49, Naples 80131, Italy.
| | - Antonella Penna
- Department of Biomolecular Sciences, University of Urbino, Viale Trieste 296, Pesaro 61121, Italy.
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Laporte M, Shao Z, Berrebi P, Laabir M, Abadie E, Faivre N, Rieuvilleneuve F, Masseret E. Isolation of 12 microsatellite markers following a pyrosequencing procedure and cross-priming in two invasive cryptic species, Alexandrium catenella (group IV) and A. tamarense (group III) (Dinophyceae). MARINE POLLUTION BULLETIN 2014; 83:302-305. [PMID: 24820642 DOI: 10.1016/j.marpolbul.2014.04.017] [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: 01/09/2014] [Revised: 04/04/2014] [Accepted: 04/06/2014] [Indexed: 06/03/2023]
Abstract
Alexandrium catenella (group IV) and Alexandrium tamarense (group III) (Dinophyceae) are two cryptic invasive phytoplankton species belonging to the A. tamarense species complex. Their worldwide spread is favored by the human activities, transportation and climate change. In order to describe their diversity in the Mediterranean Sea and understand their settlements and maintenances in this area, new microsatellite markers were developed based on Thau lagoon (France) samples of A. catenella and A. tamarense strains. In this study twelve new microsatellite markers are proposed. Five of these microsatellite markers show amplifications on A. tamarense and ten on A. catenella. Three of these 12 microsatellite markers allowed amplifications on both cryptic species. Finally, the haplotypic diversity ranged from 0.000 to 0.791 and 0.000 to 0.942 for A. catenella and A. tamarense respectively.
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Affiliation(s)
- Martin Laporte
- Institut des Sciences de l'Evolution de Montpellier, UMR 5554 UM2-CNRS-IRD, Université Montpellier II, CC065, Place E. Bataillon, 34095 Montpellier, Cedex 5, France; Département de Biologie, IBIS (Institut de Biologie Intégrative et des Systèmes), Université Laval, Québec G1V 0A6, Canada
| | - Zhaojun Shao
- Institut des Sciences de l'Evolution de Montpellier, UMR 5554 UM2-CNRS-IRD, Université Montpellier II, CC065, Place E. Bataillon, 34095 Montpellier, Cedex 5, France
| | - Patrick Berrebi
- Institut des Sciences de l'Evolution de Montpellier, UMR 5554 UM2-CNRS-IRD, Université Montpellier II, CC065, Place E. Bataillon, 34095 Montpellier, Cedex 5, France
| | - Mohamed Laabir
- Ecologie des Systèmes Marins Côtiers, UMR 5119 UM2-CNRS-IRD-Ifremer-UM1, Université Montpellier II, CC 093, 34095 Montpellier Cedex 5, France
| | - Eric Abadie
- Laboratoire Environnement Ressources Languedoc-Roussillon Ifremer, B.P. 171, 34203 Sète, France
| | - Nicolas Faivre
- Ecologie des Systèmes Marins Côtiers, UMR 5119 UM2-CNRS-IRD-Ifremer-UM1, Université Montpellier II, CC 093, 34095 Montpellier Cedex 5, France
| | - Fabien Rieuvilleneuve
- Ecologie des Systèmes Marins Côtiers, UMR 5119 UM2-CNRS-IRD-Ifremer-UM1, Université Montpellier II, CC 093, 34095 Montpellier Cedex 5, France
| | - Estelle Masseret
- Ecologie des Systèmes Marins Côtiers, UMR 5119 UM2-CNRS-IRD-Ifremer-UM1, Université Montpellier II, CC 093, 34095 Montpellier Cedex 5, France.
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Dia A, Guillou L, Mauger S, Bigeard E, Marie D, Valero M, Destombe C. Spatiotemporal changes in the genetic diversity of harmful algal blooms caused by the toxic dinoflagellateAlexandrium minutum. Mol Ecol 2014; 23:549-60. [DOI: 10.1111/mec.12617] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 11/08/2013] [Accepted: 11/19/2013] [Indexed: 11/28/2022]
Affiliation(s)
- A. Dia
- Sorbonne Universités; UPMC Univ Paris 06; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
- CNRS; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
| | - L. Guillou
- Sorbonne Universités; UPMC Univ Paris 06; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
- CNRS; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
| | - S. Mauger
- Sorbonne Universités; UPMC Univ Paris 06; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
- CNRS; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
| | - E. Bigeard
- Sorbonne Universités; UPMC Univ Paris 06; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
- CNRS; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
| | - D. Marie
- Sorbonne Universités; UPMC Univ Paris 06; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
- CNRS; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
| | - M. Valero
- Sorbonne Universités; UPMC Univ Paris 06; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
- CNRS; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
| | - C. Destombe
- Sorbonne Universités; UPMC Univ Paris 06; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
- CNRS; UMR 7144; Adaptation et diversité en milieu marin; Station Biologique de Roscoff; Place Georges Teissier CS 90074 29688 Roscoff France
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Godhe A, Egardt J, Kleinhans D, Sundqvist L, Hordoir R, Jonsson PR. Seascape analysis reveals regional gene flow patterns among populations of a marine planktonic diatom. Proc Biol Sci 2013; 280:20131599. [PMID: 24174105 PMCID: PMC3826216 DOI: 10.1098/rspb.2013.1599] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 10/03/2013] [Indexed: 02/01/2023] Open
Abstract
We investigated the gene flow of the common marine diatom, Skeletonema marinoi, in Scandinavian waters and tested the null hypothesis of panmixia. Sediment samples were collected from the Danish Straits, Kattegat and Skagerrak. Individual strains were established from germinated resting stages. A total of 350 individuals were genotyped by eight microsatellite markers. Conventional F-statistics showed significant differentiation between the samples. We therefore investigated whether the genetic structure could be explained using genetic models based on isolation by distance (IBD) or by oceanographic connectivity. Patterns of oceanographic circulation are seasonally dependent and therefore we estimated how well local oceanographic connectivity explains gene flow month by month. We found no significant relationship between genetic differentiation and geographical distance. Instead, the genetic structure of this dominant marine primary producer is best explained by local oceanographic connectivity promoting gene flow in a primarily south to north direction throughout the year. Oceanographic data were consistent with the significant FST values between several pairs of samples. Because even a small amount of genetic exchange prevents the accumulation of genetic differences in F-statistics, we hypothesize that local retention at each sample site, possibly as resting stages, is an important component in explaining the observed genetic structure.
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Affiliation(s)
- Anna Godhe
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg 405 30, Sweden
| | - Jenny Egardt
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg 405 30, Sweden
| | - David Kleinhans
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg 405 30, Sweden
- Department for Physics, Carl von Ossietzky University Oldenburg, Carl-von-Ossietzky-Strasse 9, Oldenburg 26111, Germany
| | - Lisa Sundqvist
- Department of Biological and Environmental Sciences, University of Gothenburg, PO Box 461, Gothenburg 405 30, Sweden
| | - Robinson Hordoir
- Department of Research and Development, Swedish Meteorological and Hydrological Institute, Norrköping 601 76, Sweden
| | - Per R. Jonsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Tjärnö Marine Biological Laboratory, 452 96 Strömstad, Sweden
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28
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Tahvanainen P, Alpermann TJ, Figueroa RI, John U, Hakanen P, Nagai S, Blomster J, Kremp A. Patterns of post-glacial genetic differentiation in marginal populations of a marine microalga. PLoS One 2012; 7:e53602. [PMID: 23300940 PMCID: PMC3534129 DOI: 10.1371/journal.pone.0053602] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 11/30/2012] [Indexed: 11/18/2022] Open
Abstract
This study investigates the genetic structure of an eukaryotic microorganism, the toxic dinoflagellate Alexandrium ostenfeldii, from the Baltic Sea, a geologically young and ecologically marginal brackish water estuary which is predicted to support evolution of distinct, genetically impoverished lineages of marine macroorganisms. Analyses of the internal transcribed spacer (ITS) sequences and Amplified Fragment Length Polymorphism (AFLP) of 84 A. ostenfeldii isolates from five different Baltic locations and multiple external sites revealed that Baltic A. ostenfeldii is phylogenetically differentiated from other lineages of the species and micro-geographically fragmented within the Baltic Sea. Significant genetic differentiation (F(ST)) between northern and southern locations was correlated to geographical distance. However, instead of discrete genetic units or continuous genetic differentiation, the analysis of population structure suggests a complex and partially hierarchic pattern of genetic differentiation. The observed pattern suggests that initial colonization was followed by local differentiation and varying degrees of dispersal, most likely depending on local habitat conditions and prevailing current systems separating the Baltic Sea populations. Local subpopulations generally exhibited low levels of overall gene diversity. Association analysis suggests predominately asexual reproduction most likely accompanied by frequency shifts of clonal lineages during planktonic growth. Our results indicate that the general pattern of genetic differentiation and reduced genetic diversity of Baltic populations found in large organisms also applies to microscopic eukaryotic organisms.
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Affiliation(s)
- Pia Tahvanainen
- Marine Research Centre, Finnish Environment Institute, Helsinki, Finland.
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29
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A legacy of contrasting spatial genetic structure on either side of the Atlantic-Mediterranean transition zone in a marine protist. Proc Natl Acad Sci U S A 2012; 109:20998-1003. [PMID: 23213247 DOI: 10.1073/pnas.1214398110] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The mechanisms that underpin the varied spatial genetic structures exhibited by free-living marine microorganisms remain controversial, with most studies emphasizing a high dispersal capability that should redistribute genetic diversity in contrast to most macroorganisms whose populations often retain a genetic signature of demographic response to historic climate fluctuations. We quantified the European phylogeographic structure of the marine flagellate Oxyrrhis marina and found a marked difference in spatial genetic structure, population demography, and genetic diversity between the northwest Atlantic and Mediterranean Sea that reflects the persistent separation of these regions as well as context-dependent population responses to contrasting environments. We found similar geographic variation in the level of genetic diversity in the sister species Oxyrrhis maritima. Because the capacity for wide dispersal is not always realized, historic genetic footprints of range expansion and contraction persist in contemporary populations of marine microbes, as they do in larger species. Indeed, the well-described genetic effects of climatic variation on macroorganisms provide clear, testable hypotheses about the processes that drive genetic divergence in marine microbes and thus about the response to future environmental change.
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30
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Murray SA, Patterson DJ, Thessen AE. Transcriptomics and microbial eukaryote diversity: a way forward. Trends Ecol Evol 2012; 27:651-2; author reply 652-3. [DOI: 10.1016/j.tree.2012.08.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 08/10/2012] [Indexed: 10/27/2022]
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Elphie H, Raquel G, David D, Serge P. Detecting immigrants in a highly genetically homogeneous spiny lobster population (Palinurus elephas) in the northwest Mediterranean Sea. Ecol Evol 2012; 2:2387-96. [PMID: 23145326 PMCID: PMC3492767 DOI: 10.1002/ece3.349] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 07/08/2012] [Accepted: 07/14/2012] [Indexed: 11/30/2022] Open
Abstract
We investigated the genetic structure of early benthic juveniles of the spiny lobster Palinurus elephas in the northwest Mediterranean Sea by means of ten polymorphic microsatellite markers. Non-metric Multidimensional Scaling coupled with assignment tests were used as a new approach to further delimit a reference population inside a genetically homogeneous pool of individuals and test for the presence of long distance immigrants. From this approach, we found that most early benthic juveniles collected while settling in the northwest Mediterranean Sea originated from a common larval pool. However, 4.2% of the individuals were classified as immigrants from other genetically differentiated populations, with more immigrants in the south than in the north of the sampled basin. Given currents in the northwest Mediterranean Sea and the long pelagic larval phase of P. elephas that lasts several months, this result suggest a restricted homogenized zone in the studied basin with some individuals probably coming from more differentiated populations through the Almeria-Oran Front or the Strait of Sicily.
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Affiliation(s)
- Hamdi Elphie
- USR 3278 CNRS - EPHE, Centre de Biologie et d'Ecologie Tropicale et Méditerranéenne, Université de Perpignan 52 Av. Paul Alduy, 66860, Perpignan Cedex, France
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32
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Anderson DM, Alpermann TJ, Cembella AD, Collos Y, Masseret E, Montresor M. The globally distributed genus Alexandrium: multifaceted roles in marine ecosystems and impacts on human health. HARMFUL ALGAE 2012; 14:10-35. [PMID: 22308102 PMCID: PMC3269821 DOI: 10.1016/j.hal.2011.10.012] [Citation(s) in RCA: 354] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The dinoflagellate genus Alexandrium is one of the major harmful algal bloom (HAB) genera with respect to the diversity, magnitude and consequences of blooms. The ability of Alexandrium to colonize multiple habitats and to persist over large regions through time is testimony to the adaptability and resilience of this group of species. Three different families of toxins, as well as an as yet incompletely characterized suite of allelochemicals are produced among Alexandrium species. Nutritional strategies are equally diverse, including the ability to utilize a range of inorganic and organic nutrient sources, and feeding by ingestion of other organisms. Many Alexandrium species have complex life histories that include sexuality and often, but not always, cyst formation, which is characteristic of a meroplanktonic life strategy and offers considerable ecological advantages. Due to the public health and ecosystem impacts of Alexandrium blooms, the genus has been extensively studied, and there exists a broad knowledge base that ranges from taxonomy and phylogeny through genomics and toxin biosynthesis to bloom dynamics and modeling. Here we present a review of the genus Alexandrium, focusing on the major toxic and otherwise harmful species.
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Affiliation(s)
- Donald M Anderson
- Woods Hole Oceanographic Institution, MS # 32, 266 Woods Hole Road, Woods Hole MA 02543; 508 289 2351
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