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1.
Eur J Protistol ; 78: 125694, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33500175

RESUMO

Denis Lynn (1947-2018) was an outstanding protistologist, applying multiple techniques and data sources and thus pioneering an integrative approach in order to investigate ciliate biology. For example, he recognized the importance of the ultrastructure for inferring ciliate phylogeny, based on which he developed his widely accepted classification scheme for the phylum Ciliophora. In this paper, recent findings regarding the evolution and systematics of both peritrichs and the mainly marine planktonic oligotrichean spirotrichs are discussed and compared with the concepts and hypotheses formulated by Denis Lynn. Additionally, the state of knowledge concerning the diversity of ciliates in bromeliad phytotelmata and amitosis in ciliates is reviewed.


Assuntos
Cilióforos , Biodiversidade , Cilióforos/classificação , Cilióforos/fisiologia , Classificação , Roma , Sociedades
2.
Ann Parasitol ; 66(2): 227-230, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32592544

RESUMO

A total of 578 specimens of common carp (Cyprinus carpio) from eight the most significant and larger cyprinid aquaculture facilities in Macedonia (fish farms and cage culture systems) were examined for parasitological investigation. Protozoa Apiosoma piscicola was found in cage culture system on Globochica reservoir. In this fish farm, a total of 127 fish samples were examined for parasitological investigation, in which parasite infestation with A. piscicola was found on fins and gills in 79 specimens of common carp, in winter season. The prevalence of A. piscicola in common carp was 62.20%, while the mean intensity was 17.58. Our findings of A. piscicola in common carp (C. carpio) are first recorded in Macedonia. At the same time, common carp represent new host for A. piscicola in Macedonian waters.


Assuntos
Carpas , Infecções por Cilióforos/veterinária , Cilióforos , Doenças dos Peixes , Animais , Aquicultura , Carpas/parasitologia , Cilióforos/classificação , Cilióforos/fisiologia , Infecções por Cilióforos/epidemiologia , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , República da Macedônia do Norte/epidemiologia
3.
Gene ; 743: 144624, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32224274

RESUMO

The giant ciliate Stentor coeruleus (S. coeruleus) is a suitable model organism for studying morphogenesis and regeneration at the single-cell level. It contains a prominent structure on the anterior end of the cell, known as the oral apparatus (OA). OA can be induced to shed by urea treatment and then new OA regenerates via a series of defined morphological events and the cell resumes normal feeding activity. We identified OA constituents in S. coeruleus by mass spectrometry. A total of 882 OA-associated proteins were identified; the homologs of 181 of these are known OA constituents in other organisms. The expression pattern of OA-associated genes during regeneration was investigated using single-cell transcriptome sequencing. The expression of most OA-associated genes was high during regeneration, indicating their stable expression after OA shedding. We also identified OA-associated differentially expressed genes that may be involved in regulating OA reconstruction. In summary, this study gives preliminary insight into the molecular basis of OA in S. coeruleus.


Assuntos
Cilióforos/fisiologia , Genes de Protozoários/genética , Proteínas de Protozoários/metabolismo , Regeneração , Espectrometria de Massas , Proteômica , Proteínas de Protozoários/genética , Análise de Sequência de RNA , Análise de Célula Única
4.
Proc Biol Sci ; 287(1919): 20192818, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31992166

RESUMO

Habitat fragmentation is expected to reduce dispersal movements among patches as a result of increased inter-patch distances. Furthermore, since habitat fragmentation is expected to raise the costs of moving among patches in the landscape, it should hamper the ability or tendency of organisms to perform informed dispersal decisions. Here, we used microcosms of the ciliate Tetrahymena thermophila to test experimentally whether habitat fragmentation, manipulated through the length of corridors connecting patches differing in temperature, affects habitat choice. We showed that a twofold increase of inter-patch distance can as expected hamper the ability of organisms to choose their habitat at immigration. Interestingly, it also increased their habitat choice at emigration, suggesting that organisms become choosier in their decision to either stay or leave their patch when obtaining information about neighbouring patches gets harder. This study points out that habitat fragmentation might affect not only dispersal rate but also the level of non-randomness of dispersal, with emigration and immigration decisions differently affected. These consequences of fragmentation might considerably modify ecological and evolutionary dynamics of populations facing environmental changes.


Assuntos
Cilióforos/fisiologia , Ecossistema , Temperatura , Territorialidade
5.
Fish Shellfish Immunol ; 96: 107-113, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31805410

RESUMO

In fish, interferon (IFN) regulatory factor 2 (IRF2) is a regulator of the type I IFN-dependent immune response, thereby playing a crucial role in innate immunity. However, the specific mechanism by which IRF2 regulates type II IFN in fish remains unclear. In the present study, first, to analyse the potential role of golden pompano (Trachinotus ovatus) IRF2 (ToIRF2) in the immune response, the mRNA level of ToIRF2 was detected by quantitative real-time polymerase chain reaction (qRT-PCR) after parasite infection. ToIRF2 was upregulated at early time points in both local infection sites (skin and gill) and system immune tissues (liver, spleen, and head-kidney) after stimulation with Cryptocaryon irritans. Second, to investigate the modulation effect of ToIRF2 on type II IFN (interferon gamma, IFNγ) expression, a promoter analysis was performed using progressive deletion mutations of ToIFNγ. The expression level of IFNγ-5 was highest among the five truncated mutants in response to ToIRF2, indicating that the core promoter region was located from -189 bp to +120 bp, which included the IRF2 binding sites. Mutation analyses showed that the activity of the ToIFNγ promoter dramatically decreased after the targeted mutation of the M1, M2 or M3 binding sites. Additionally, electrophoretic mobile shift assay (EMSA) confirmed that IRF2 interacted with the M1 binding site in the ToIFNγ promoter region to dominate ToIFNγ expression. Finally, overexpressing ToIRF2 in vitro notably increased ToIFNγ and the transcription of several type II IFN/IRF-based signalling pathway genes. These results suggested that ToIRF2 might be involved in the host defence against C. irritans infection and contribute to a better understanding of the transcriptional mechanisms by which ToIRF2 regulates type II IFN in fish.


Assuntos
Doenças dos Peixes/imunologia , Peixes/genética , Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Fator Regulador 2 de Interferon/genética , Fator Regulador 2 de Interferon/imunologia , Animais , Sequência de Bases , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/parasitologia , Infecções por Cilióforos/veterinária , Doenças dos Peixes/parasitologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Interferon gama/genética , Interferon gama/metabolismo , Alinhamento de Sequência/veterinária
6.
Microb Ecol ; 79(4): 815-822, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31720759

RESUMO

External environments to microbial eukaryotic communities often change gradually with time. However, whether the responses of microbial eukaryotic communities to these gradually changed environments are continuous or hysteretic and the mechanisms underlying these responses are largely unknown. Here, we used a microcosm to investigate the temporal variation of microbial eukaryotic communities with the gradually decreased nutrient concentrations (nitrogen and phosphorus). We found the differences of microbial eukaryotic community composition and species richness between the control and treatment groups were low during the days 0 to 12, although the nutrient concentrations decreased rapidly during this period in treatment group. However, these differences were clear during the days 14 to 18, although the nutrient concentrations decreased slowly during this period in treatment group. The mechanisms for these results are that the strong homogenous selection (perhaps due to the biotic factors) during the days 8 to 10 in treatment group might enhance the stability of microbial eukaryotic communities. However, the continuously decreased nutrient concentrations weakened the homogenous selection and promoted the strength of environmental filtering, and therefore resulted in the distinct change of microbial eukaryotic communities during the days 14 to 18 in treatment group. Fungi, Chlorophyta and Chrysophyta which associated with the nutrient removal played important roles in this hysteretic change of microbial eukaryotic communities. Overall, our findings suggest that disentangling the non-linear response of communities to gradual environmental changes is essential for understanding ecosystem restoration and degradation in future.


Assuntos
Clorófitas/fisiologia , Cilióforos/fisiologia , Água Doce/química , Fungos/fisiologia , Nutrientes/deficiência , Clorófitas/metabolismo , Cilióforos/metabolismo , Eucariotos , Eutrofização , Fungos/metabolismo , Microbiota , Micobioma/fisiologia , Nitrogênio/deficiência , Fósforo/deficiência
7.
Mol Phylogenet Evol ; 143: 106687, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31740334

RESUMO

Rumen ciliates are a specialized group of ciliates exclusively found in the anaerobic, carbohydrate-rich rumen microenvironment. However, the molecular and mechanistic basis of the physiological and behavioral adaptation of ciliates to the rumen microenvironment is undefined. We used single-cell transcriptome sequencing to explore the adaptive evolution of three rumen ciliates: two entodiniomorphids, Entodinium furca and Diplodinium dentatum; and one vestibuliferid, Isotricha intestinalis. We found that all three species are members of monophyletic orders within the class Litostomatea, with E. furca and D. dentatum in Entodiniomorphida and I. intestinalis in Vestibuliferida. The two entodiniomorphids might use H2-producing mitochondria and the vestibuliferid might use anaerobic mitochondria to survive under strictly anaerobic conditions. Moreover, carbohydrate-active enzyme (CAZyme) genes were identified in all three species, including cellulases, hemicellulases, and pectinases. The evidence that all three species have acquired prokaryote-derived genes by horizontal gene transfer (HGT) to digest plant biomass includes a significant enrichment of gene ontology categories such as cell wall macromolecule catabolic process and carbohydrate catabolic process and the identification of genes in common between CAZyme and HGT groups. These findings suggest that HGT might be an important mechanism in the adaptive evolution of ciliates to the rumen microenvironment.


Assuntos
Cilióforos/genética , Rúmen/parasitologia , Transcriptoma , Adaptação Fisiológica , Anaerobiose , Animais , Metabolismo dos Carboidratos , Celulases/genética , Cilióforos/classificação , Cilióforos/fisiologia , Transferência Genética Horizontal , Glicosídeo Hidrolases/genética , Filogenia , Poligalacturonase/genética , RNA-Seq , Rúmen/metabolismo , Análise de Célula Única
8.
Fish Shellfish Immunol ; 98: 819-831, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31751659

RESUMO

Massive infection caused by Cryptocaryon irritans is detrimental to the development of marine aquaculture. Recently, our lab found that Nibea albiflora has low sensitivity and low mortality to C. irritans infection. The present study was designed to investigate the mechanisms of the N. albiflora response to C. irritans infection by analyzing transcriptome changes in the skin. Skin samples of control and experimental groups with C. irritans infection were collected at 24 and 72 h (24 h control, 24 h post-infection, 72 h control, and 72 h post-infection). Three parallels were set for each group and sample time, and a total of 12 skin samples were collected for sequencing. Overall, 297,489,843 valid paired-end reads and 48,817 unigenes were obtained with an overall length of 59,010,494 nt. In pairwise comparisons, changes in expression occurred in 1621 (764 upregulated and 857 downregulated), 285 (180 upregulated and 105 downregulated), 993 (489 upregulated and 504 downregulated), and 37 (8 upregulated and 29 downregulated) genes at 24 h control vs 24 h post-infection, 72 h control vs 72 h post-infection, 24 h post-infection vs 72 h post-infection, and 24 h control vs 72 h control, respectively. Gene Ontology (GO) analysis of differentially expressed genes (DEGs) indicated that the number of genes enriched in GO sub-categories were ordered 24 h control vs 24 h post-infection > 24 h post-infection vs 72 h post-infection >72 h control vs 72 h post-infection > 24 h control vs 72 h control. Further analysis showed that immune-related GO terms (including immune system process, complement activation, and humoral immunity) were significantly enriched at both 72 h control vs 72 h post-infection and 24 h post-infection vs 72 h post-infection, but no immune-related GO terms were significantly enriched in the 24 h control vs 72 h control and at 24 h control vs 24 h post-infection, indicating that C. irritans infection mainly affected the physiological metabolism of N. albiflora at an early stage (24 h), and immune-related genes play an important role at a later stage (72 h) of infection. In KEGG pathway analysis, the complement and coagulation cascade pathway are involved in early infection. Hematopoietic cell lineage, natural killer (NK) cell-mediated cytotoxicity, and the intestinal immune network for IgA production are involved in later infection. Further analysis showed that the alternative pathway of complement and coagulation cascades plays an important role in the resistance of N. albiflora to early C. irritans infection. During late infection, CD34, IgM, and IgD were significantly upregulated in the hematopoietic cell lineage pathway. CCR9 was significantly downregulated, and IGH and PIGR were significantly upregulated in the intestinal immune network for IgA production. GZMB and IGH were significantly downregulated in NK cell-mediated cytotoxicity. These findings indicate that acquired immunity at the mRNA level was initiated during later infection. In addition, the IL-17 signaling pathway was enriched by downregulated DEGs at 24 h post-infection vs 72 h post-infection, suggesting the inflammatory response at 24 h was stronger than at 72 h and the invasion of the parasite has a greater impact on the host.


Assuntos
Infecções por Cilióforos/veterinária , Cilióforos/fisiologia , Doenças dos Peixes/imunologia , Perciformes , Dermatopatias/veterinária , Transcriptoma , Animais , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/parasitologia , Doenças dos Peixes/parasitologia , Perfilação da Expressão Gênica/veterinária , Pele/metabolismo , Dermatopatias/imunologia , Dermatopatias/parasitologia
9.
Eur J Protistol ; 72: 125643, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31734636

RESUMO

The colonization features of periphytic protozoa have proved to be a useful tool for indicating water quality status in aquatic ecosystems. In order to reveal the seasonal variations in colonization dynamics of the protozoa, a 1-year baseline survey was carried out in coastal waters of the Yellow Sea, northern China. Using glass slides as artificial substrates, a total of 240 slides were collected at a depth of 1 m in four seasons after colonization periods of 3, 7, 10, 14, 21, and 28 days. A total of 122 ciliate species were identified with 21 dominant species. The colonization dynamics of the protozoa were well fitted to the MacArthur-Wilson and logistic models in all four seasons (P < 0.05). However, the equilibrium species numbers (Seq), colonization rates (G), and the time to 90% Seq (T90%) represented a clear seasonal variability: (1) more or less similar levels in spring and autumn (Seq = 29/23; G = 0.301/0.296; T90%=7.650/7.779); (2) with a significant difference in summer and winter (Seq = 32/121; G = 0.708/0.005; T90% = 3.252/479.705). Multivariate approaches demonstrated that the exposure time for the species composition and community structure of the protozoa to an equilibrium period were 10-14 days in spring and autumn, but less and more time periods were needed in summer and winter, respectively. Based on the results, we suggest that the colonization dynamics of periphytic protozoa were different within four seasons, and an optimal sampling strategy for monitoring surveys should be modified during different seasons in marine ecosystems.


Assuntos
Biodiversidade , Cilióforos/fisiologia , Estações do Ano , Água do Mar/parasitologia , China , Monitoramento Ambiental , Modelos Logísticos
10.
Microb Ecol ; 79(1): 64-72, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31147731

RESUMO

Temporal programs synchronised with the daily cycle are of adaptive importance for organisms exposed to periodic fluctuations. This study deepens into several aspects of the exogenous and endogenous nature of microbial grazers. We investigated the diel rhythms of cell division and feeding activity of four marine protists under different light regimes. In particular, we tested if the feeding cycle of protistan grazers could be mediated by a light-aided enhancement of prey digestion, and also explored the consequences of cell division on diel feeding rhythms. Cell division occurred at night for the heterotrophic dinoflagellates Gyrodinium dominans and Oxyrrhis marina. In contrast, the mixotrophic dinoflagellate Karlodinium armiger and the ciliate Strombidium sp. mostly divided during the day. Additionally, a significant diurnal feeding rhythm was observed in all species. When exposed to continuous darkness, nearly all species maintained the cell division rhythm, but lost the feeding cycle within several hours/days (with the exception of O. marina that kept the rhythm for 9.5 days). Additional feeding experiments under continuous light also showed the same pattern. We conclude that the feeding rhythms of protistan grazers are generally regulated not by cell division nor by the enhancement of digestion by light. Our study, moreover, indicates that the cell division cycle is under endogenous control, whereas an external trigger is required to maintain the feeding rhythm, at least for most of the species studied here.


Assuntos
Cilióforos/fisiologia , Dinoflagelados/fisiologia , Divisão Celular/efeitos da radiação , Cilióforos/efeitos da radiação , Dinoflagelados/efeitos da radiação , Processos Heterotróficos , Luz
11.
Mol Biol Evol ; 37(2): 524-539, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31647561

RESUMO

Hydrogenosomes are H2-producing mitochondrial homologs found in some anaerobic microbial eukaryotes that provide a rare intracellular niche for H2-utilizing endosymbiotic archaea. Among ciliates, anaerobic and aerobic lineages are interspersed, demonstrating that the switch to an anaerobic lifestyle with hydrogenosomes has occurred repeatedly and independently. To investigate the molecular details of this transition, we generated genomic and transcriptomic data sets from anaerobic ciliates representing three distinct lineages. Our data demonstrate that hydrogenosomes have evolved from ancestral mitochondria in each case and reveal different degrees of independent mitochondrial genome and proteome reductive evolution, including the first example of complete mitochondrial genome loss in ciliates. Intriguingly, the FeFe-hydrogenase used for generating H2 has a unique domain structure among eukaryotes and appears to have been present, potentially through a single lateral gene transfer from an unknown donor, in the common aerobic ancestor of all three lineages. The early acquisition and retention of FeFe-hydrogenase helps to explain the facility whereby mitochondrial function can be so radically modified within this diverse and ecologically important group of microbial eukaryotes.


Assuntos
Cilióforos/classificação , Perfilação da Expressão Gênica/métodos , Mitocôndrias/genética , Análise de Sequência de DNA/métodos , Aerobiose , Anaerobiose , Cilióforos/fisiologia , Evolução Molecular , Transferência Genética Horizontal , Genoma Mitocondrial , Hidrogênio/metabolismo , Filogenia , Análise de Sequência de RNA
12.
J R Soc Interface ; 16(161): 20190410, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31795860

RESUMO

There is still a significant gap between our understanding of neural circuits and the behaviours they compute-i.e. the computations performed by these neural networks (Carandini 2012 Nat. Neurosci. 15, 507-509. (doi:10.1038/nn.3043)). Cellular decision-making processes, learning, behaviour and memory formation-all that have been only associated with animals with neural systems-have also been observed in many unicellular aneural organisms, namely Physarum, Paramecium and Stentor (Tang & Marshall2018 Curr. Biol. 28, R1180-R1184. (doi:10.1016/j.cub.2018.09.015)). As these are fully functioning organisms, yet being unicellular, there is a much better chance to elucidate the detailed mechanisms underlying these learning processes in these organisms without the complications of highly interconnected neural circuits. An intriguing learning behaviour observed in Stentor roeseli (Jennings 1902 Am. J. Physiol. Legacy Content 8, 23-60. (doi:10.1152/ajplegacy.1902.8.1.23)) when stimulated with carmine has left scientists puzzled for more than a century. So far, none of the existing learning paradigm can fully encapsulate this particular series of five characteristic avoidance reactions. Although we were able to observe all responses described in the literature and in a previous study (Dexter et al. 2019), they do not conform to any particular learning model. We then investigated whether models inferred from machine learning approaches, including decision tree, random forest and feed-forward artificial neural networks could infer and predict the behaviour of S. roeseli. Our results showed that an artificial neural network with multiple 'computational' neurons is inefficient at modelling the single-celled ciliate's avoidance reactions. This has highlighted the complexity of behaviours in aneural organisms. Additionally, this report will also discuss the significance of elucidating molecular details underlying learning and decision-making processes in these unicellular organisms, which could offer valuable insights that are applicable to higher animals.


Assuntos
Comportamento Animal , Cilióforos/fisiologia , Aprendizado de Máquina , Rede Nervosa , Animais , Modelos Biológicos , Gravação em Vídeo
13.
Curr Biol ; 29(24): 4323-4329.e2, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31813604

RESUMO

Complex behavior is associated with animals with nervous systems, but decision-making and learning also occur in non-neural organisms [1], including singly nucleated cells [2-5] and multi-nucleate synctia [6-8]. Ciliates are single-cell eukaryotes, widely dispersed in aquatic habitats [9], with an extensive behavioral repertoire [10-13]. In 1906, Herbert Spencer Jennings [14, 15] described in the sessile ciliate Stentor roeseli a hierarchy of responses to repeated stimulation, which are among the most complex behaviors reported for a singly nucleated cell [16, 17]. These results attracted widespread interest [18, 19] and exert continuing fascination [7, 20-22] but were discredited during the behaviorist orthodoxy by claims of non-reproducibility [23]. These claims were based on experiments with the motile ciliate Stentor coeruleus. We acquired and maintained the correct organism in laboratory culture and used micromanipulation and video microscopy to confirm Jennings' observations. Despite significant individual variation, not addressed by Jennings, S. roeseli exhibits avoidance behaviors in a characteristic hierarchy of bending, ciliary alteration, contractions, and detachment, which is distinct from habituation or conditioning. Remarkably, the choice of contraction versus detachment is consistent with a fair coin toss. Such behavioral complexity may have had an evolutionary advantage in protist ecosystems, and the ciliate cortex may have provided mechanisms for implementing such behavior prior to the emergence of multicellularity. Our work resurrects Jennings' pioneering insights and adds to the list of exceptional features, including regeneration [24], genome rearrangement [25], codon reassignment [26], and cortical inheritance [27], for which the ciliate clade is renowned.


Assuntos
Aprendizagem da Esquiva/fisiologia , Cilióforos/fisiologia , Cilióforos/genética , Cilióforos/metabolismo , Tomada de Decisões/fisiologia , Ecossistema , Células Eucarióticas/metabolismo , Células Eucarióticas/fisiologia
14.
Fish Shellfish Immunol ; 94: 661-674, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521785

RESUMO

The yellow drum Nibea albiflora is less susceptible to Cryptocaryon irritans infection than is the case with other marine fishes such as Larimichthys crocea, Lateolabrax japonicus, and Pagrus major. To investigate further their resistance mechanism, we infected the N. albiflora with the C. irritans at a median lethal concentration of 2050 theronts/g fish. The skins of the infected and the uninfected fishes were sampled at 24 h and 72 h followed by an extensive analysis of metabolism. The study results revealed that there were 2694 potential metabolites. At 24 h post-infection, 12 metabolites were up-regulated and 17 were down-regulated whereas at 72 h post-infection, 22 metabolites were up-regulated and 26 were down-regulated. Pathway enrichment analysis shows that the differential enriched pathways were higher at 24 h with 22 categories and 58 subcategories (49 up, 9 down) than at 72 h whereby the differential enriched pathways were 6 categories and 8 subcategories (4 up, 4 down). In addition, the principal component analysis (PCA) plot shows that at 24 h the metabolites composition of infected group were separately clustered to uninfected group while at 72 h the metabolites composition in infected group were much closer to uninfected group. This indicated that C. irritans caused strong metabolic stress on the N. albiflora at 24 h and restoration of the dysregulated metabolic state took place at 72 h of infection. Also, at 72 h post infection a total of 17 compounds were identified as potential biomarkers. Furthermore, out of 2694 primary metabolites detected, 23 metabolites could be clearly identified and semi quantified with a known identification number and assigned into 66 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Most of the enriched KEGG pathways were mainly from metabolic pathway classes, including the metabolic pathway, biosynthesis of secondary metabolites, taurine and hypotaurine metabolism, purine metabolism, linoleic acid metabolism, phenylalanine, tyrosine and tryptophan biosynthesis. Others were glyoxylate and dicarboxylate metabolism, glutathione metabolism, and alanine, aspartate, and glutamate metabolism. Moreover, out of the identified metabolites, only 6 metabolites were statistically differentially expressed, namely, L -glutamate (up-regulated) at 24 h was important for energy and precursor for other glutathiones and instruments of preventing oxidative injury; 15-hydroxy- eicosatetraenoic acid (15-HETE), (S)-(-)-2-Hydroxyisocaproic acid, and adenine (up-regulated) at 72 h were important for anti-inflammatory and immune responses during infection; others were delta-valerolactam and betaine which were down-regulated compared to uninfected group at 72 h, might be related to immure responses including stimulation of immune system such as production of antibodies. Our results therefore further advance our understanding on the immunological regulation of N. albiflora during immune response against infections as they indicated a strong relationship between skin metabolome and C. irritans infection.


Assuntos
Infecções por Cilióforos/veterinária , Doenças dos Peixes/imunologia , Imunidade Inata/imunologia , Metaboloma/imunologia , Perciformes , Pele/imunologia , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/parasitologia , Doenças dos Peixes/parasitologia
15.
Fish Shellfish Immunol ; 93: 863-870, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31422178

RESUMO

Interleukins (ILs) are a subgroup of cytokines, which are molecules involved in the intercellular regulation of the immune system. These cytokines have been extensively studied in mammalian models, but systematic analyses of fish are limited. In the current study, 3 IL genes from golden pompano (Trachinotus ovatus) were characterized. The IL-1ß protein contains IL-1 family signature motif, and four long helices (αA - αD) in IL-11 and IL-34, which were well conserved. All 3 ILs clustered phylogenetically with their respective IL relatives in mammalian and other teleost species. Under normal physiological conditions, the expression of IL-1ß, IL-11, and IL-34 were detected at varied levels in the 11 tissues examined. Most of the 3 ILs examined were highly expressed in liver, spleen, kidney, gill, or skin. Following pathogenic bacterial, viral, or parasitic challenge, IL-1ß, IL-11, and IL-34 exhibited distinctly different expression profiles in a time-, tissue-, and pathogen-dependent manner. In general, IL-1ß was expressed at higher levels following challenge with all pathogens examined than was observed for IL-11 and IL-34. Furthermore, Streptococcus agalactiae and Cryptocaryon irritans caused higher levels of IL-1ß and IL-11 expression than Vibrio harveyi and viral nervous necrosis virus (VNNV). The increased expression of IL-34 caused by VNNV and C. irritans were higher than that caused by V. harveyi and S. agalactiae. These results suggest that these 3 ILs in T. ovatus may play different effect pathogen type specific responses.


Assuntos
Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/veterinária , Perfilação da Expressão Gênica/veterinária , Interleucina-11/genética , Interleucina-11/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucinas/genética , Interleucinas/imunologia , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
16.
Nature ; 571(7766): 560-564, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292551

RESUMO

The biophysical relationships between sensors and actuators1-5 have been fundamental to the development of complex life forms. Swimming organisms generate abundant flows that persist in aquatic environments6-13, and responding promptly to external stimuli is key to survival14-19. Here we present the discovery of 'hydrodynamic trigger waves' in cellular communities of the protist Spirostomum ambiguum that propagate-in a manner similar to a chain reaction20-22-hundreds of times faster than their swimming speed. By coiling its cytoskeleton, Spirostomum can contract its long body by 60% within milliseconds23, experiencing accelerations that can reach forces of 14g. We show that a single cellular contraction (the transmitter) generates long-ranged vortex flows at intermediate Reynolds numbers that can, in turn, trigger neighbouring cells (the receivers). To measure the sensitivity to hydrodynamic signals in these receiver cells, we present a high-throughput suction-flow device for probing mechanosensitive ion channels24 by back-calculating the microscopic forces on the cell membrane. We analyse and quantitatively model the ultra-fast hydrodynamic trigger waves in a universal framework of antenna and percolation theory25,26, and reveal a phase transition that requires a critical colony density to sustain collective communication. Our results suggest that this signalling could help to organize cohabiting communities over large distances and influence long-term behaviour through gene expression (comparable to quorum sensing16). In more immediate terms, because contractions release toxins27, synchronized discharges could facilitate the repulsion of large predators or immobilize large prey. We postulate that numerous aquatic organisms other than protists could coordinate their behaviour using variations of hydrodynamic trigger waves.


Assuntos
Comunicação Celular , Cilióforos/citologia , Cilióforos/fisiologia , Hidrodinâmica , Natação/fisiologia , Movimentos da Água , Animais , Organismos Aquáticos/citologia , Organismos Aquáticos/genética , Organismos Aquáticos/fisiologia , Biofísica , Cilióforos/genética , Citoesqueleto/fisiologia , Comportamento Predatório , Reologia , Fatores de Tempo
17.
Fish Shellfish Immunol ; 93: 308-312, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31352113

RESUMO

Initiation of the innate immune response requires recognition of pathogen-associated molecular patterns by pathogen recognition receptors such as Toll-like receptors (TLRs). MyD88 adaptor-like (Mal) is an adaptor that responds to TLR activation and acts as a bridging adaptor for MyD88. In the present study, the open reading frame of Mal was identified in orange-spotted grouper (Epinephelus coioides), and named EcMal. It contained 831 bp encoding 276 aa, and was encoded by a 1299 bp DNA sequence with three exons and two introns. EcMal and the Mal sequence of other species shared different degrees of sequence identity, and clustered into the same group. EcMal was distributed in all tissues tested in healthy grouper, with the highest expression level in the head kidney. After infection with Cryptocaryon irritans, the expression level of EcMal was up-regulated in the gill and spleen. In addition, EcMal exhibited global cytosolic and nucleus localization, and could significantly activate NF-κB activity in grouper spleen cells.


Assuntos
Bass/genética , Bass/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Sequência de Aminoácidos , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/veterinária , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Fator 88 de Diferenciação Mieloide/química , Filogenia , Alinhamento de Sequência/veterinária
18.
Fish Shellfish Immunol ; 92: 690-697, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31276788

RESUMO

Macrophage expressed gene 1 (Mpeg1) is a molecule that can form pores and destroy the cell membrane of invading pathogens. In this study, we identified two Mpeg1 isoforms from the orange-spotted grouper (Epinephelus coioides) and named them EcMpeg1a and EcMpeg1b. Predicted proteins of the two EcMpeg1s contained a signal peptide, a conserved membrane attack complex/perforin (MACPF) domain, a transmembrane segment, and an intracellular region. Sequence alignment demonstrated that two EcMpeg1 proteins share a high sequence identity with that of other teleosts. Tissue distribution analysis showed that EcMpeg1s were expressed in all tissues tested in healthy grouper, with the highest expression in the head kidney and spleen. After infection with the ciliate parasite Cryptocaryon irritans, expression of the two EcMpeg1s was significantly upregulated in the spleen and gills. Furthermore, the recombinant EcMpeg1a showed antiparasitic and antibacterial activity against Gram-negative and -positive bacteria, whereas EcMpeg1b had an inhibitory effect only against Gram-positive bacteria. These results indicated that EcMpeg1s play an important role in the host response against invading pathogens.


Assuntos
Bass/genética , Bass/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Sequência de Aminoácidos , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/veterinária , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Proteínas de Membrana/química , Filogenia , Alinhamento de Sequência/veterinária
19.
Protist ; 170(3): 283-286, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181471

RESUMO

Many protists form cell colonies. Among them several are filter-feeders depending on suspended food particles such as bacteria. It has been suggested that the formation of colonies enhances feeding efficiency and implied that - in the case of colonial choanoflagellates - it was an adaptive trait that led to the evolution of metazoans. Here it is shown experimentally - for a colonial peritrich ciliate and for a choanoflagellate - that colony-formation does not enhance the efficiency of filter-feeding relative to solitary cells and that the adaptive significance of cell colony-formation must have some other explanation.


Assuntos
Coanoflagelados/fisiologia , Cilióforos/fisiologia , Coanoflagelados/citologia , Cilióforos/citologia , Comportamento Alimentar/fisiologia
20.
Mar Pollut Bull ; 142: 452-456, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31232323

RESUMO

To identify the influence of tidal events on community functioning of periphytic ciliates for monitoring program and community research using biological trait analysis, a 3-month baseline survey was conducted in Korean coastal waters using the polyurethane foam enveloped slide system (PFES) and conventional slide system (CS). Although the periphytic ciliate communities had similar biological trait categories, they represented considerable differences in community functioning and functional diversity measures within the PFES and CS systems. Multivariate analyses revealed different ways of the temporal shift in community functioning of the ciliates in both systems. The dispersion analysis demonstrated that the CS system was sensitive to the strong disturbance of tidal current and circulation compared to the PFES system. These findings suggest that the strong tidal event may significantly influence the output of analysis on community functioning of periphytic ciliates for bioassessment in marine ecosystems.


Assuntos
Cilióforos/fisiologia , Monitoramento Ambiental/métodos , Água do Mar , Ecossistema , Monitoramento Ambiental/instrumentação , Análise Multivariada , Fenótipo , República da Coreia
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