Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 176(6): 1340-1355.e15, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30799037

RESUMO

Th17 cells provide protection at barrier tissues but may also contribute to immune pathology. The relevance and induction mechanisms of pathologic Th17 responses in humans are poorly understood. Here, we identify the mucocutaneous pathobiont Candida albicans as the major direct inducer of human anti-fungal Th17 cells. Th17 cells directed against other fungi are induced by cross-reactivity to C. albicans. Intestinal inflammation expands total C. albicans and cross-reactive Th17 cells. Strikingly, Th17 cells cross-reactive to the airborne fungus Aspergillus fumigatus are selectively activated and expanded in patients with airway inflammation, especially during acute allergic bronchopulmonary aspergillosis. This indicates a direct link between protective intestinal Th17 responses against C. albicans and lung inflammation caused by airborne fungi. We identify heterologous immunity to a single, ubiquitous member of the microbiota as a central mechanism for systemic induction of human anti-fungal Th17 responses and as a potential risk factor for pulmonary inflammatory diseases.


Assuntos
Candida albicans/imunologia , Células Th17/imunologia , Células Th17/metabolismo , Aspergillus fumigatus/imunologia , Aspergillus fumigatus/patogenicidade , Candida albicans/patogenicidade , Reações Cruzadas/imunologia , Fibrose Cística/imunologia , Fibrose Cística/microbiologia , Humanos , Imunidade , Imunidade Heteróloga/imunologia , Células Th17/fisiologia
2.
PLoS Biol ; 19(3): e3001100, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33690708

RESUMO

The issues facing academic mothers have been discussed for decades. Coronavirus Disease 2019 (COVID-19) is further exposing these inequalities as womxn scientists who are parenting while also engaging in a combination of academic related duties are falling behind. These inequities can be solved by investing strategically in solutions. Here we describe strategies that would ensure a more equitable academy for working mothers now and in the future. While the data are clear that mothers are being disproportionately impacted by COVID-19, many groups could benefit from these strategies. Rather than rebuilding what we once knew, let us be the architects of a new world.


Assuntos
COVID-19/epidemiologia , Mães/estatística & dados numéricos , Pesquisadores/estatística & dados numéricos , Sexismo/estatística & dados numéricos , Ensino/estatística & dados numéricos , COVID-19/economia , COVID-19/psicologia , Feminino , Humanos , Mães/psicologia , Poder Familiar/psicologia , Poder Familiar/tendências , SARS-CoV-2/isolamento & purificação , Sexismo/psicologia , Sexismo/tendências
3.
Glob Chang Biol ; 28(1): 33-45, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34710272

RESUMO

The pollution of the marine environment with microplastics is pervasive. However, microplastic concentrations in the seawater are lower than the number of particles entering the oceans, suggesting that plastic particles accumulate in environmental sinks. Yet, the exact long-term sinks related to the "missing plastic" phenomenon are barely explored. Sediments in nearshore biogenic habitats are known to trap large amounts of microplastics, but also the three-dimensional structures of coral reefs might serve as unique, living long-term sinks. The main framework builders, reef-building corals, have been shown to ingest and overgrow microplastics, potentially leading to a deposition of particles in reef structures. However, little is known about the number of deposited particles and the underlying processes determining the permanent deposition in the coral skeletons. To test whether corals may act as living long-term sink for microplastic, we exposed four reef-building coral species to polyethylene microplastics (200 particles L-1 ) in an 18-month laboratory experiment. We found microplastics in all treatment specimens, with low numbers of particles trapped in the coral tissue (up to 2 particles per cm2 ) and much higher numbers in the skeleton (up to 84 particles per cm3 ). The numbers of particles accumulated in the coral skeletons were mainly related to coral growth (i.e., skeletal growth in volume), suggesting that deposition is a regularly occurring stochastic process. We estimate that reef-building corals may remove 0.09%-2.82% of the bioavailable microplastics from tropical shallow-reef waters per year. Our study shows for the first time that microplastic particles accumulate permanently in a biological sink, helping to explain the "missing plastic" phenomenon. This highlights the importance of coral reefs for the ecological balance of the oceans and reinforces the need to protect them, not only to mitigate the effects of climate change but also to preserve their ecosystem services as long-term sink for microplastic.


Assuntos
Antozoários , Microplásticos , Animais , Recifes de Corais , Ecossistema , Plásticos
4.
Glob Chang Biol ; 28(5): 1753-1765, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34343392

RESUMO

Over this century, coral reefs will run the gauntlet of climate change, as marine heatwaves (MHWs) become more intense and frequent, and ocean acidification (OA) progresses. However, we still lack a quantitative assessment of how, and to what degree, OA will moderate the responses of corals to MHWs as they intensify throughout this century. Here, we first projected future MHW intensities for tropical regions under three future greenhouse gas emissions scenario (representative concentration pathways, RCP2.6, RCP4.5 and RCP8.5) for the near-term (2021-2040), mid-century (2041-2060) and late-century (2081-2100). We then combined these MHW intensity projections with a global data set of 1,788 experiments to assess coral attribute performance and survival under the three emissions scenarios for the near-term, mid-century and late-century in the presence and absence of OA. Although warming and OA had predominately additive impacts on the coral responses, the contribution of OA in affecting most coral attributes was minor relative to the dominant role of intensifying MHWs. However, the addition of OA led to greater decreases in photosynthesis and survival under intermediate and unrestricted emissions scenario for the mid- and late-century than if intensifying MHWs were considered as the only driver. These results show that role of OA in modulating coral responses to intensifying MHWs depended on the focal coral attribute and extremity of the scenario examined. Specifically, intensifying MHWs and OA will cause increasing instances of coral bleaching and substantial declines in coral productivity, calcification and survival within the next two decades under the low and intermediate emissions scenario. These projections suggest that corals must rapidly adapt or acclimatize to projected ocean conditions to persist, which is far more likely under a low emissions scenario and with increasing efforts to manage reefs to enhance resilience.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Mudança Climática , Recifes de Corais , Concentração de Íons de Hidrogênio , Oceanos e Mares , Água do Mar
5.
Bioessays ; 42(7): e2000004, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32548850

RESUMO

Animals and plants are metaorganisms and associate with microbes that affect their physiology, stress tolerance, and fitness. Here the hypothesis that alteration of the microbiome may constitute a fast-response mechanism to environmental change is examined. This is supported by recent reciprocal transplant experiments with reef corals, which have shown that their microbiome adapts to thermally variable habitats and changes over time when transplanted into different environments. Further, inoculation of corals with beneficial bacteria increases their stress tolerance. But corals differ in their ability to flexibly associate with different bacteria. How scales of microbiome flexibility may reflect different metaorganism adaptation mechanisms is discussed and future directions for research are pinpointed. It is posited that microbiome flexibility is a broad phenomenon that contributes to the ability of organisms to respond to environmental change. Importantly, adapting with microbial help may provide an alternate route to organismal adaptation that facilitates rapid responses.


Assuntos
Antozoários , Microbiota , Adaptação Fisiológica , Animais , Bactérias/genética , Simbiose
6.
Glob Chang Biol ; 27(21): 5532-5546, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34391212

RESUMO

Our understanding of the response of reef-building corals to changes in their physical environment is largely based on laboratory experiments, analysis of long-term field data, and model projections. Experimental data provide unique insights into how organisms respond to variation of environmental drivers. However, an assessment of how well experimental conditions cover the breadth of environmental conditions and variability where corals live successfully is missing. Here, we compiled and analyzed a globally distributed dataset of in-situ seasonal and diurnal variability of key environmental drivers (temperature, pCO2 , and O2 ) critical for the growth and livelihood of reef-building corals. Using a meta-analysis approach, we compared the variability of environmental conditions assayed in coral experimental studies to current and projected conditions in their natural habitats. We found that annual temperature profiles projected for the end of the 21st century were characterized by distributional shifts in temperatures with warmer winters and longer warm periods in the summer, not just peak temperatures. Furthermore, short-term hourly fluctuations of temperature and pCO2 may regularly expose corals to conditions beyond the projected average increases for the end of the 21st century. Coral reef sites varied in the degree of coupling between temperature, pCO2 , and dissolved O2 , which warrants site-specific, differentiated experimental approaches depending on the local hydrography and influence of biological processes on the carbonate system and O2 availability. Our analysis highlights that a large portion of the natural environmental variability at short and long timescales is underexplored in experimental designs, which may provide a path to extend our understanding on the response of corals to global climate change.


Assuntos
Antozoários , Animais , Mudança Climática , Recifes de Corais , Oceanos e Mares , Temperatura
7.
Glob Chang Biol ; 24(2): e474-e484, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29044761

RESUMO

Tropical reefs have been impacted by thermal anomalies caused by global warming that induced coral bleaching and mortality events globally. However, there have only been very few recordings of bleaching within the Red Sea despite covering a latitudinal range of 15° and consequently it has been considered a region that is less sensitive to thermal anomalies. We therefore examined historical patterns of sea surface temperature (SST) and associated anomalies (1982-2012) and compared warming trends with a unique compilation of corresponding coral bleaching records from throughout the region. These data indicated that the northern Red Sea has not experienced mass bleaching despite intensive Degree Heating Weeks (DHW) of >15°C-weeks. Severe bleaching was restricted to the central and southern Red Sea where DHWs have been more frequent, but far less intense (DHWs <4°C-weeks). A similar pattern was observed during the 2015-2016 El Niño event during which time corals in the northern Red Sea did not bleach despite high thermal stress (i.e. DHWs >8°C-weeks), and bleaching was restricted to the central and southern Red Sea despite the lower thermal stress (DHWs < 8°C-weeks). Heat stress assays carried out in the northern (Hurghada) and central (Thuwal) Red Sea on four key reef-building species confirmed different regional thermal susceptibility, and that central Red Sea corals are more sensitive to thermal anomalies as compared to those from the north. Together, our data demonstrate that corals in the northern Red Sea have a much higher heat tolerance than their prevailing temperature regime would suggest. In contrast, corals from the central Red Sea are close to their thermal limits, which closely match the maximum annual water temperatures. The northern Red Sea harbours reef-building corals that live well below their bleaching thresholds and thus we propose that the region represents a thermal refuge of global importance.


Assuntos
Antozoários , Recifes de Corais , Refúgio de Vida Selvagem , Animais , Aquecimento Global , Oceano Índico , Temperatura
8.
J Phycol ; 54(4): 447-460, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29696650

RESUMO

Large-scale environmental disturbances may impact both partners in coral host-Symbiodinium systems. Elucidation of the assembly patterns in such complex and interdependent communities may enable better prediction of environmental impacts across coral reef ecosystems. In this study, we investigated how the community composition and diversity of dinoflagellate symbionts in the genus Symbiodinium were distributed among 12 host species from six taxonomic orders (Actinaria, Alcyonacea, Miliolida, Porifera, Rhizostoma, Scleractinia) and in the reef water and sediments at Lizard Island, Great Barrier Reef before the 3rd Global Coral Bleaching Event. 454 pyrosequencing of the ITS2 region of Symbiodinium yielded 83 operational taxonomic units (OTUs) at a 97% similarity cut-off. Approximately half of the Symbiodinium OTUs from reef water or sediments were also present in symbio. OTUs belonged to six clades (A-D, F-G), but community structure was uneven. The two most abundant OTUs (100% matches to types C1 and A3) comprised 91% of reads and OTU C1 was shared by all species. However, sequence-based analysis of these dominant OTUs revealed host species specificity, suggesting that genetic similarity cut-offs of Symbiodinium ITS2 data sets need careful evaluation. Of the less abundant OTUs, roughly half occurred at only one site or in one species and the background Symbiodinium communities were distinct between individual samples. We conclude that sampling multiple host taxa with differing life history traits will be critical to fully understand the symbiont diversity of a given system and to predict coral ecosystem responses to environmental change and disturbance considering the differential stress response of the taxa within.


Assuntos
Biodiversidade , Dinoflagellida/genética , Variação Genética , Animais , Antozoários , Recifes de Corais , DNA de Protozoário/análise , DNA Espaçador Ribossômico/análise , Dinoflagellida/classificação , Dinoflagellida/fisiologia , Sedimentos Geológicos/parasitologia , Sequenciamento de Nucleotídeos em Larga Escala , Queensland , Simbiose
9.
Mycoses ; 60(8): 508-516, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28730644

RESUMO

Rare invasive fungal diseases (IFD) are challenging for the treating physicians because of their unspecific clinical presentation, as well as the lack of standardised diagnostic and effective treatment strategies. Late onset of treatment and inappropriate medication is associated with high mortality, thus, urging the need for a better understanding of these diseases. The purpose of FungiScope™ is to continuously collect clinical information and specimens to improve the knowledge on epidemiology and eventually improve patient management of these orphan diseases. FungiScope™ was founded in 2003, and today, collaborators from 66 countries support the registry. So far, clinical data of 794 cases have been entered using a web-based approach. Within the growing network of experts, new collaborations developed, leading to several publications of comprehensive analyses of patient subgroups identified from the registry. Data extracted from FungiScope™ have also been used as the sole control group for the approval of a new antifungal drug. Due to the rarity of these diseases, a global registry is an appropriate method of pooling the scarce and scattered information. Joining efforts across medical specialities and geographical borders is key for researching rare IFD. Here, we describe the structure and management of the FungiScope™ registry.


Assuntos
Doenças Transmissíveis Emergentes , Saúde Global , Micoses , Doenças Raras , Sistema de Registros , Humanos , Hospedeiro Imunocomprometido , Infecções Fúngicas Invasivas , Controle de Qualidade , Sistema de Registros/normas
10.
Mycoses ; 60(4): 273-279, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28150341

RESUMO

Saprochaete and Geotrichum spp. are rare emerging fungi causing invasive fungal diseases in immunosuppressed patients and scarce evidence is available for treatment decisions. Among 505 cases of rare IFD from the FungiScope™ registry, we identified 23 cases of invasive infections caused by these fungi reported from 10 countries over a 12-year period. All cases were adults and previous chemotherapy with associated neutropenia was the most common co-morbidity. Fungaemia was confirmed in 14 (61%) cases and deep organ involvement included lungs, liver, spleen, central nervous system and kidneys. Fungi were S. capitata (n=14), S. clavata (n=5), G. candidum (n=2) and Geotrichum spp. (n=2). Susceptibility was tested in 16 (70%) isolates. All S. capitata and S. clavata isolates with the exception of one S. capitata (MIC 4 mg/L) isolate had MICs>32 mg/L for caspofungin. For micafungin and anidulafungin, MICs varied between 0.25 and >32 mg/L. One case was diagnosed postmortem, 22 patients received targeted treatment, with voriconazole as the most frequent first line drug. Overall mortality was 65% (n=15). Initial echinocandin treatment was associated with worse outcome at day 30 when compared to treatment with other antifungals (amphotericin B ± flucytosine, voriconazole, fluconazole and itraconazole) (P=.036). Echinocandins are not an option for these infections.


Assuntos
Geotricose/microbiologia , Geotrichum/isolamento & purificação , Infecções Fúngicas Invasivas/microbiologia , Sistema de Registros , Saccharomycetales/isolamento & purificação , Adolescente , Adulto , Idoso , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Feminino , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Fungemia/diagnóstico , Fungemia/tratamento farmacológico , Fungemia/microbiologia , Geotricose/tratamento farmacológico , Geotricose/mortalidade , Geotrichum/classificação , Geotrichum/efeitos dos fármacos , Geotrichum/genética , Humanos , Hospedeiro Imunocomprometido , Infecções Fúngicas Invasivas/tratamento farmacológico , Infecções Fúngicas Invasivas/mortalidade , Lipopeptídeos/farmacologia , Lipopeptídeos/uso terapêutico , Masculino , Micafungina , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Neutropenia/complicações , Neutropenia/tratamento farmacológico , Neutropenia/microbiologia , Saccharomycetales/classificação , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/genética , Voriconazol/farmacologia , Voriconazol/uso terapêutico , Adulto Jovem
11.
Xenotransplantation ; 23(5): 338-46, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27610605

RESUMO

BACKGROUND: Xenotransplantation is considered to be a promising solution to the growing demand for suitable donor organs for transplantation. Despite tremendous progress in the generation of pigs with multiple genetic modifications thought to be necessary to overcoming the severe rejection responses after pig-to-non-human primate xenotransplantation, the production of knockout pigs by somatic cell nuclear transfer (SCNT) is still an inefficient process. Producing genetically modified pigs by intracytoplasmic microinjection of porcine zygotes is an alluring alternative. The porcine GGTA1 gene encodes for the α1,3-galactosyltransferase that synthesizes the Gal epitopes on porcine cells which constitute the major antigen in a xenotransplantation setting. GGTA1-KO pigs have successfully been produced by transfecting somatic cells with zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), or CRISPR/Cas targeting GGTA1, followed by SCNT. METHODS: Here, we microinjected a CRISPR/Cas9 vector coding for a single-guide RNA (sgRNA) targeting exon 8 of the GGTA1 gene into the cytoplasm of 97 in vivo-derived porcine zygotes and transferred 86 of the microinjected embryos into three hormonally synchronized recipients. Fetuses and piglets were analyzed by flow cytometry for remaining Gal epitopes. DNA was sequenced to detect mutations at the GGTA1 locus. RESULTS: Two of the recipients remained pregnant as determined by ultrasound scanning on day 25 of gestation. One pregnancy was terminated on day 26, and six healthy fetuses were recovered. The second pregnancy was allowed to go to term and resulted in the birth of six healthy piglets. Flow cytometry analysis revealed the absence of Gal epitopes in four of six fetuses (66%), indicating a biallelic KO of GGTA1. Additionally, three of the six live-born piglets (50%) did not express Gal epitopes on their cell surface. Two fetuses and two piglets showed a mosaicism with a mixed population of Gal-free and Gal-expressing cells. Only a single piglet did not have any genomic modifications. Genomic sequencing revealed indel formation at the GGTA1 locus ranging from +17 bp to -20 bp. CONCLUSIONS: These results demonstrate the efficacy of CRISPR/Cas to generate genetic modifications in pigs by simplified technology, such as intracytoplasmic microinjection into zygotes, which would significantly facilitate the production of genetically modified pigs suitable for xenotransplantation. Importantly, this simplified injection protocol avoids the penetration of the vulnerable pronuclear membrane, and is thus compatible with higher survival rates of microinjected embryos, which in turn facilitates production of genetically modified piglets.


Assuntos
Citoplasma , Galactosiltransferases/metabolismo , Zigoto , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas/genética , Citoplasma/genética , Galactosiltransferases/deficiência , Técnicas de Inativação de Genes/métodos , Microinjeções/métodos , Técnicas de Transferência Nuclear , Suínos
12.
Trends Microbiol ; 32(5): 422-434, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38216372

RESUMO

Stony corals are poster child holobionts due to their intimate association with diverse microorganisms from all domains of life. We are only beginning to understand the diverse functions of most of these microbial associates, including potential main contributors to holobiont health and resilience. Among these, bacteria of the elusive genus Endozoicomonas are widely perceived as beneficial symbionts based on their genomic potential and their high prevalence and ubiquitous presence in coral tissues. Simultaneously, evidence of pathogenic and parasitic Endozoicomonas lineages in other marine animals is emerging. Synthesizing the current knowledge on the association of Endozoicomonas with marine holobionts, we challenge the perception of a purely mutualistic coral-Endozoicomonas relationship and propose directions to elucidate its role along the symbiotic spectrum.


Assuntos
Antozoários , Recifes de Corais , Simbiose , Animais , Antozoários/microbiologia , Antozoários/fisiologia , Microbiota , Filogenia
13.
Sci Rep ; 14(1): 12757, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38830941

RESUMO

Reef-building corals live in highly hydrodynamic environments, where water flow largely controls the complex chemical microenvironments surrounding them-the concentration boundary layer (CBL). The CBL may be key to alleviate ocean acidification (OA) effects on coral colonies by partially isolating them. However, OA effects on coral CBL remain poorly understood, particularly under different flow velocities. Here, we investigated these effects on the reef-building corals Acropora cytherea, Pocillopora verrucosa, and Porites cylindrica. We preconditioned corals to a control (pH 8.0) and OA (pH 7.8) treatment for four months and tested how low flow (2 cm s-1) and moderate flow (6 cm s-1) affected O2 and H+ CBL traits (thickness, surface concentrations, and flux) inside a unidirectional-flow chamber. We found that CBL traits differed between species and flow velocities. Under OA, traits remained generally stable across flows, except surface pH. In all species, the H+ CBL was thin and led to lower surface pH. Still, low flow thickened H+ CBLs and increased light elevation of surface pH. In general, our findings reveal a weak to null OA modulation of the CBL. Moreover, the OA-buffering capacity by the H+ CBL may be limited in coral species, though low flow could enhance CBL sheltering.


Assuntos
Antozoários , Oceanos e Mares , Oxigênio , Água do Mar , Antozoários/fisiologia , Antozoários/metabolismo , Animais , Concentração de Íons de Hidrogênio , Oxigênio/metabolismo , Oxigênio/química , Água do Mar/química , Recifes de Corais , Movimentos da Água , Acidificação dos Oceanos
14.
Sci Total Environ ; 913: 169485, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38143004

RESUMO

The negative impacts of microplastic on reef-building corals are often attributed to the feeding responses to these particles. Although reactions to and ingestion of microplastic are frequently reported, a quantitative comparison to natural particles and of the factors influencing these responses is largely missing. Thus, this study aims to compare the feeding rates of corals to microplastic and natural particles, considering factors influencing these responses. Specifically, we I) studied the feeding responses of corals to microplastic, natural food, and non-food particles, II) examined the influence of biotic factors (i.e., biofilm on the particles and presence of natural food), III) evaluated species-specific differences in feeding responses to microplastic particles, and IV) applied a toxicodynamic model for species- and concentration-dependent risk assessments. We assessed the feeding responses of 11 coral species, spanning different life-history strategies and growth forms in experimental feeding trials. The results showed that the feeding responses of corals to microplastic differ from those to naturally occurring particles. Reactions to microplastic and natural food occurred equally often, while sand was more frequently rejected. Yet, the ingestion process was much more selective, and microplastic was ingested less frequently than natural food. The presence of a biofilm and natural food had activating effects on the feeding behavior of the corals on microplastic. Generally, coral species that exhibit a higher degree of heterotrophic feeding also reacted more often to microplastic. The species- and concentration-dependent toxicodynamic risk model built on these data reveals that most tested coral species are unlikely to be at risk under present environmental concentration levels. However, highly heterotrophic feeders, such as Blastomussa merleti, or generally vulnerable species, such as Pocillopora verrucosa, need special consideration. These findings help to better evaluate the responses of corals to microplastic and their risk in an increasingly polluted ocean.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Microplásticos , Recifes de Corais , Plásticos/toxicidade , Processos Heterotróficos
15.
Sci Total Environ ; 912: 169276, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38086480

RESUMO

Marine debris, particularly microdebris (< 1 mm) poses a potential threat to marine life, including reef-building corals. While previous research has mainly focused on the impact of single polymer microplastics, the effects of natural microdebris, composed of a mixture of materials, have not been explored. Therefore, this study aimed to assess the effects of different microdebris, originating from major sources of pollution, on reef-building corals. For this, we exposed two scleractinian coral species, Pocillopora verrucosa and Stylophora pistillata, known to frequently ingest microplastics, to four types of microdebris in an 8-week laboratory experiment: fragmented environmental plastic debris, artificial fibers from clothing, residues from the automobile sector consisting of tire wear, brake abrasion, and varnish flakes, a single polymer microplastic treatment consisting of polyethylene particles, and a microdebris-free control treatment. Specifically, we (I) compared the effects of the different microdebris on coral growth, necrosis, and photosynthesis, (II) investigated the difference between the microdebris mixtures and the exposure to the single polymer treatment, and (III) identified potential mechanisms causing species-specific effects by contrasting the feeding responses of the two coral species on microdebris and natural food. We show that the fibers and tire wear had the strongest effects on coral physiology, with P. verrucosa being more affected than S. pistillata. Both species showed increased volume growth in response to the microdebris treatments, accompanied by decreased calcification in P. verrucosa. Photosynthetic efficiency of the symbionts was enhanced in both species. The species-specific physiological responses might be attributed to feeding reactions, with P. verrucosa responding significantly more often to microdebris than S. pistillata. These findings highlight the effect of different microdebris on coral physiology and the need for future studies to use particle mixtures to better mimic naturally occurring microdebris and assess its effect on corals in more detail.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Recifes de Corais , Plásticos/toxicidade , Microplásticos , Fotossíntese
16.
Curr Biol ; 34(12): 2693-2701.e4, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38788707

RESUMO

Sea urchins are primary herbivores on coral reefs, regulating algal biomass and facilitating coral settlement and growth.1,2,3,4,5,6,7,8,9,10,11,12 Recurring mass mortality events (MMEs) of Diadema species Gray, 1825 have been recorded globally,13,14,15,16,17,18,19,20,21,22,23 the most notorious and ecologically significant of which occurred in the Caribbean in 1983,14,17,19,20 contributing to the shift from coral to algal-dominated ecosystems.17,24,25 Recently, first evidence of Diadema setosum mass mortality was reported from the eastern Mediterranean Sea.23 Here, we report extensive mass mortalities of several diadematoid species inhabiting the Red Sea and Western Indian Ocean (WIO)26,27,28 including first evidence of mortalities in the genus Echinothrix Peters, 1853. Mortalities initiated in the Gulf of Aqaba on December 2022 and span the Red Sea, the Gulf of Oman, and the Western Indian Ocean (Réunion Island), with population declines reaching 100% at some sites. Infected individuals are characterized by spine loss and tissue necrosis, resulting in exposed skeletons (i.e., tests) and mortality. Molecular diagnostics of the 18S rRNA gene confirm the presence of a waterborne scuticociliate protozoan most closely related to Philaster apodigitiformis in infected specimens-identical to the pathogen found in the 2022 Caribbean mass mortality of Diadema antillarum.13,15,18 Collapse of these key benthic grazers in the Red Sea and Western Indian Ocean may lead to algal dominance over corals, threatening the stability of coral reefs on a regional scale.29,30,31,32 We issue a warning regarding the further expansion of mortalities and call for immediate monitoring and conservation efforts for these key ecological species.


Assuntos
Ouriços-do-Mar , Animais , Oceano Índico , Ouriços-do-Mar/parasitologia , Ouriços-do-Mar/fisiologia , Recifes de Corais
17.
Trends Microbiol ; 32(3): 252-269, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37758552

RESUMO

The provision of probiotics benefits the health of a wide range of organisms, from humans to animals and plants. Probiotics can enhance stress resilience of endangered organisms, many of which are critically threatened by anthropogenic impacts. The use of so-called 'probiotics for wildlife' is a nascent application, and the field needs to reflect on standards for its development, testing, validation, risk assessment, and deployment. Here, we identify the main challenges of this emerging intervention and provide a roadmap to validate the effectiveness of wildlife probiotics. We cover the essential use of inert negative controls in trials and the investigation of the probiotic mechanisms of action. We also suggest alternative microbial therapies that could be tested in parallel with the probiotic application. Our recommendations align approaches used for humans, aquaculture, and plants to the emerging concept and use of probiotics for wildlife.


Assuntos
Animais Selvagens , Probióticos , Animais , Humanos , Aquicultura
18.
Nat Commun ; 14(1): 3039, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264002

RESUMO

Coral reefs are among the most diverse ecosystems on Earth. They support high biodiversity of multicellular organisms that strongly rely on associated microorganisms for health and nutrition. However, the extent of the coral reef microbiome diversity and its distribution at the oceanic basin-scale remains to be explored. Here, we systematically sampled 3 coral morphotypes, 2 fish species, and planktonic communities in 99 reefs from 32 islands across the Pacific Ocean, to assess reef microbiome composition and biogeography. We show a very large richness of reef microorganisms compared to other environments, which extrapolated to all fishes and corals of the Pacific, approximates the current estimated total prokaryotic diversity for the entire Earth. Microbial communities vary among and within the 3 animal biomes (coral, fish, plankton), and geographically. For corals, the cross-ocean patterns of diversity are different from those known for other multicellular organisms. Within each coral morphotype, community composition is always determined by geographic distance first, both at the island and across ocean scale, and then by environment. Our unprecedented sampling effort of coral reef microbiomes, as part of the Tara Pacific expedition, provides new insight into the global microbial diversity, the factors driving their distribution, and the biocomplexity of reef ecosystems.


Assuntos
Antozoários , Microbiota , Animais , Recifes de Corais , Oceano Pacífico , Biodiversidade , Peixes , Plâncton
19.
Nat Commun ; 14(1): 3037, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264015

RESUMO

Health and resilience of the coral holobiont depend on diverse bacterial communities often dominated by key marine symbionts of the Endozoicomonadaceae family. The factors controlling their distribution and their functional diversity remain, however, poorly known. Here, we study the ecology of Endozoicomonadaceae at an ocean basin-scale by sampling specimens from three coral genera (Pocillopora, Porites, Millepora) on 99 reefs from 32 islands across the Pacific Ocean. The analysis of 2447 metabarcoding and 270 metagenomic samples reveals that each coral genus harbored a distinct new species of Endozoicomonadaceae. These species are composed of nine lineages that have distinct biogeographic patterns. The most common one, found in Pocillopora, appears to be a globally distributed symbiont with distinct metabolic capabilities, including the synthesis of amino acids and vitamins not produced by the host. The other lineages are structured partly by the host genetic lineage in Pocillopora and mainly by the geographic location in Porites. Millepora is more rarely associated to Endozoicomonadaceae. Our results show that different coral genera exhibit distinct strategies of host-Endozoicomonadaceae associations that are defined at the bacteria lineage level.


Assuntos
Antozoários , Gammaproteobacteria , Animais , Antozoários/microbiologia , Oceano Pacífico , Ecologia , Bactérias , Recifes de Corais
20.
Sci Data ; 10(1): 326, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264047

RESUMO

Coral reef science is a fast-growing field propelled by the need to better understand coral health and resilience to devise strategies to slow reef loss resulting from environmental stresses. Key to coral resilience are the symbiotic interactions established within a complex holobiont, i.e. the multipartite assemblages comprising the coral host organism, endosymbiotic dinoflagellates, bacteria, archaea, fungi, and viruses. Tara Pacific is an ambitious project built upon the experience of previous Tara Oceans expeditions, and leveraging state-of-the-art sequencing technologies and analyses to dissect the biodiversity and biocomplexity of the coral holobiont screened across most archipelagos spread throughout the entire Pacific Ocean. Here we detail the Tara Pacific workflow for multi-omics data generation, from sample handling to nucleotide sequence data generation and deposition. This unique multidimensional framework also includes a large amount of concomitant metadata collected side-by-side that provide new assessments of coral reef biodiversity including micro-biodiversity and shape future investigations of coral reef dynamics and their fate in the Anthropocene.


Assuntos
Antozoários , Recifes de Corais , Animais , Biodiversidade , Ecossistema
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA