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Pesquisa : G08.686.784.830 [Categoria DeCS]
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[PMID]:29176784
[Au] Autor:Fu C; Heitman J
[Ad] Endereço:Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, United States of America.
[Ti] Título:PRM1 and KAR5 function in cell-cell fusion and karyogamy to drive distinct bisexual and unisexual cycles in the Cryptococcus pathogenic species complex.
[So] Source:PLoS Genet;13(11):e1007113, 2017 Nov.
[Is] ISSN:1553-7404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Sexual reproduction is critical for successful evolution of eukaryotic organisms in adaptation to changing environments. In the opportunistic human fungal pathogens, the Cryptococcus pathogenic species complex, C. neoformans primarily undergoes bisexual reproduction, while C. deneoformans undergoes both unisexual and bisexual reproduction. During both unisexual and bisexual cycles, a common set of genetic circuits regulates a yeast-to-hyphal morphological transition, that produces either monokaryotic or dikaryotic hyphae. As such, both the unisexual and bisexual cycles can generate genotypic and phenotypic diversity de novo. Despite the similarities between these two cycles, genetic and morphological differences exist, such as the absence of an opposite mating-type partner and monokaryotic instead of dikaryotic hyphae during C. deneoformans unisexual cycle. To better understand the similarities and differences between these modes of sexual reproduction, we focused on two cellular processes involved in sexual reproduction: cell-cell fusion and karyogamy. We identified orthologs of the plasma membrane fusion protein Prm1 and the nuclear membrane fusion protein Kar5 in both Cryptococcus species, and demonstrated their conserved roles in cell fusion and karyogamy during C. deneoformans α-α unisexual reproduction and C. deneoformans and C. neoformans a-α bisexual reproduction. Notably, karyogamy occurs inside the basidum during bisexual reproduction in C. neoformans, but often occurs earlier following cell fusion during bisexual reproduction in C. deneoformans. Characterization of these two genes also showed that cell fusion is dispensable for solo unisexual reproduction in C. deneoformans. The blastospores produced along hyphae during C. deneoformans unisexual reproduction are diploid, suggesting that diploidization occurs early during hyphal development, possibly through either an endoreplication pathway or cell fusion-independent karyogamy events. Taken together, our findings suggest distinct mating mechanisms for unisexual and bisexual reproduction in Cryptococcus, exemplifying distinct evolutionary trajectories within this pathogenic species complex.
[Mh] Termos MeSH primário: Cryptococcus neoformans/genética
Proteínas Fúngicas/genética
Genes Fúngicos Tipo Acasalamento/genética
Reprodução Assexuada/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Núcleo Celular/genética
Núcleo Celular/metabolismo
Cryptococcus neoformans/citologia
Cryptococcus neoformans/crescimento & desenvolvimento
Diploide
Regulação da Expressão Gênica no Desenvolvimento
Regulação Fúngica da Expressão Gênica
Hifas/genética
Hifas/crescimento & desenvolvimento
Fusão de Membrana/genética
Microscopia Confocal
Modelos Genéticos
Mutação
Homologia de Sequência de Aminoácidos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungal Proteins)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:180307
[Lr] Data última revisão:
180307
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pgen.1007113


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[PMID]:29224342
[Au] Autor:Iwai R; Han C; Govindam SVS; Ojika M
[Ad] Endereço:Graduate School of Bioagricultural Sciences, Nagoya University , Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
[Ti] Título:Lycosides, Unusual Carotenoid-Derived Terpenoid Glycosides from a Vegetable Juice, Inhibit Asexual Reproduction of the Plant Pathogen Phytophthora.
[So] Source:J Agric Food Chem;66(1):163-169, 2018 Jan 10.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Vegetable juices, typical culture media for the plant pathogen Phytophthora, effectively induce its asexual reproduction (zoosporangia formation). However, some chromatographic fractions from a vegetable juice were found to inhibit asexual reproduction. Bioassay-guided chromatographic steps led to the isolation of four novel compounds, named lycosides A-D, 1-4, that could be metabolic products from a carotenoid. They showed 50% inhibitory activity against the asexual reproduction of P. capsici at 2.1-7.6 µM. The structure-activity relationship and the universality of the inhibitory activity within the Phytophthora genus were also investigated. In addition, the quantitative analysis of lycosides in fresh vegetables and vegetable juices revealed that tomato is the source of these active substances. These food-derived chemicals could help provide safe agents to control the outbreak of the agricultural pest Phytophthora in fields.
[Mh] Termos MeSH primário: Sucos de Frutas e Vegetais
Glicosídeos/farmacologia
Phytophthora/efeitos dos fármacos
Terpenos/farmacologia
[Mh] Termos MeSH secundário: Carotenoides/isolamento & purificação
Carotenoides/farmacologia
Glicosídeos/química
Glicosídeos/isolamento & purificação
Lycopersicon esculentum/química
Estrutura Molecular
Phytophthora/patogenicidade
Phytophthora/fisiologia
Reprodução Assexuada/efeitos dos fármacos
Relação Estrutura-Atividade
Terpenos/química
Terpenos/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glycosides); 0 (Terpenes); 36-88-4 (Carotenoids)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171212
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b04766


  3 / 1435 MEDLINE  
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[PMID]:28467481
[Au] Autor:Gyawali R; Zhao Y; Lin J; Fan Y; Xu X; Upadhyay S; Lin X
[Ad] Endereço:Department of Biology, Texas A&M University, College Station, United States of America.
[Ti] Título:Pheromone independent unisexual development in Cryptococcus neoformans.
[So] Source:PLoS Genet;13(5):e1006772, 2017 May.
[Is] ISSN:1553-7404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The fungus Cryptococcus neoformans can undergo a-α bisexual and unisexual reproduction. Completion of both sexual reproduction modes requires similar cellular differentiation processes and meiosis. Although bisexual reproduction generates equal number of a and α progeny and is far more efficient than unisexual reproduction under mating-inducing laboratory conditions, the α mating type dominates in nature. Population genetic studies suggest that unisexual reproduction by α isolates might have contributed to this sharply skewed distribution of the mating types. However, the predominance of the α mating type and the seemingly inefficient unisexual reproduction observed under laboratory conditions present a conundrum. Here, we discovered a previously unrecognized condition that promotes unisexual reproduction while suppressing bisexual reproduction. Pheromone is the principal stimulus for bisexual development in Cryptococcus. Interestingly, pheromone and other components of the pheromone pathway, including the key transcription factor Mat2, are not necessary but rather inhibitory for Cryptococcus to complete its unisexual cycle under this condition. The inactivation of the pheromone pathway promotes unisexual reproduction despite the essential role of this pathway in non-self-recognition during bisexual reproduction. Nonetheless, the requirement for the known filamentation regulator Znf2 and the expression of hyphal or basidium specific proteins remain the same for pheromone-dependent or independent sexual reproduction. Transcriptome analyses and an insertional mutagenesis screen in mat2Δ identified calcineurin being essential for this process. We further found that Znf2 and calcineurin work cooperatively in controlling unisexual development in this fungus. These findings indicate that Mat2 acts as a repressor of pheromone-independent unisexual development while serving as an activator for a-α bisexual development. The bi-functionality of Mat2 might have allowed it to act as a toggle switch for the mode of sexual development in this ubiquitous eukaryotic microbe.
[Mh] Termos MeSH primário: Cryptococcus neoformans/crescimento & desenvolvimento
Genes Fúngicos Tipo Acasalamento
Fator de Acasalamento/metabolismo
[Mh] Termos MeSH secundário: Calcineurina/genética
Calcineurina/metabolismo
Cryptococcus neoformans/genética
Proteínas Fúngicas/genética
Proteínas Fúngicas/metabolismo
Fator de Acasalamento/genética
Reprodução Assexuada
Esporos Fúngicos/genética
Esporos Fúngicos/crescimento & desenvolvimento
Fatores de Transcrição/genética
Fatores de Transcrição/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungal Proteins); 0 (Transcription Factors); 61194-02-3 (Mating Factor); EC 3.1.3.16 (Calcineurin)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:180124
[Lr] Data última revisão:
180124
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pgen.1006772


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[PMID]:28467318
[Au] Autor:Yang X; Kaj KJ; Schwab DJ; Collins ES
[Ad] Endereço:Department of Physics and Astronomy, Northwestern University, Evanston, IL, United States of America. These authors contributed equally to this work.
[Ti] Título:Coordination of size-control, reproduction and generational memory in freshwater planarians.
[So] Source:Phys Biol;14(3):036003, 2017 May 23.
[Is] ISSN:1478-3975
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Uncovering the mechanisms that control size, growth, and division rates of organisms reproducing through binary division means understanding basic principles of their life cycle. Recent work has focused on how division rates are regulated in bacteria and yeast, but this question has not yet been addressed in more complex, multicellular organisms. We have, over the course of several years, assembled a unique large-scale data set on the growth and asexual reproduction of two freshwater planarian species, Dugesia japonica and Girardia tigrina, which reproduce by transverse fission and succeeding regeneration of head and tail pieces into new planarians. We show that generation-dependent memory effects in planarian reproduction need to be taken into account to accurately capture the experimental data. To achieve this, we developed a new additive model that mixes multiple size control strategies based on planarian size, growth, and time between divisions. Our model quantifies the proportions of each strategy in the mixed dynamics, revealing the ability of the two planarian species to utilize different strategies in a coordinated manner for size control. Additionally, we found that head and tail offspring of both species employ different mechanisms to monitor and trigger their reproduction cycles. Thus, we find a diversity of strategies not only between species but between heads and tails within species. Our additive model provides two advantages over existing 2D models that fit a multivariable splitting rate function to the data for size control: firstly, it can be fit to relatively small data sets and can thus be applied to systems where available data is limited. Secondly, it enables new biological insights because it explicitly shows the contributions of different size control strategies for each offspring type.
[Mh] Termos MeSH primário: Tamanho Corporal
Planárias/fisiologia
Regeneração
Reprodução Assexuada
[Mh] Termos MeSH secundário: Animais
Modelos Biológicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171226
[Lr] Data última revisão:
171226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1088/1478-3975/aa70c4


  5 / 1435 MEDLINE  
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[PMID]:27777035
[Au] Autor:Zhu Q; Sun L; Lian J; Gao X; Zhao L; Ding M; Li J; Liang Y
[Ad] Endereço:College of Plant Protection, Shandong Agricultural University, Taian 271018, China.
[Ti] Título:The phospholipase C (FgPLC1) is involved in regulation of development, pathogenicity, and stress responses in Fusarium graminearum.
[So] Source:Fungal Genet Biol;97:1-9, 2016 12.
[Is] ISSN:1096-0937
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Phospholipase C (PLC) is an important phospholipid hydrolase that plays critical roles in various biological processes in eukaryotic cells. To elucidate the functions of PLC in morphogenesis and pathogenesis in Fusarium graminearum, deletion mutants were constructed of all six FgPLC genes identified in this study. Deletion of FgPLC1, but not the other five FgPLC genes, affected hyphal growth and conidiation. The FgPLC1 deletion mutant (Δplc1) also was defective in conidium germination and germ tube growth. It was sterile in selfing crosses and had increased sensitivities to hyperosmotic and cell wall stresses. The Δplc1 mutant showed reduced DON production and virulence during infection in flowering wheat heads. Deletion of FgPLC1 decreased the phosphorylation levels of both Gpmk1 and Mgv1 MAP kinases. qRT-PCR analysis showed that several genes related to defective phenotypes were down-regulated in the Δplc1 mutant. Taken together, these results indicated that FgPLC1 is important for hyphal growth, plant infection, and sexual or asexual reproduction, and it may be functionally related to MAP kinases in F. graminearum.
[Mh] Termos MeSH primário: Fusarium/genética
Doenças das Plantas/genética
Esporos Fúngicos/genética
Fosfolipases Tipo C/genética
[Mh] Termos MeSH secundário: Parede Celular/genética
Parede Celular/microbiologia
Fusarium/crescimento & desenvolvimento
Fusarium/patogenicidade
Regulação Fúngica da Expressão Gênica
Proteínas Quinases Ativadas por Mitógeno/genética
Fosforilação
Doenças das Plantas/microbiologia
Reprodução Assexuada/genética
Deleção de Sequência
Esporos Fúngicos/crescimento & desenvolvimento
Esporos Fúngicos/patogenicidade
Triticum/genética
Triticum/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
EC 2.7.11.24 (Mitogen-Activated Protein Kinases); EC 3.1.4.- (Type C Phospholipases)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171214
[Lr] Data última revisão:
171214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161030
[St] Status:MEDLINE


  6 / 1435 MEDLINE  
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[PMID]:28658268
[Au] Autor:Wu MY; Mead ME; Kim SC; Rokas A; Yu JH
[Ad] Endereço:Departments of Bacteriology and Genetics, University of Wisconsin, Madison, Wisconsin, United States of America.
[Ti] Título:WetA bridges cellular and chemical development in Aspergillus flavus.
[So] Source:PLoS One;12(6):e0179571, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bridging cellular reproduction and survival is essential for all life forms. Aspergillus fungi primarily reproduce by forming asexual spores called conidia, whose formation and maturation is governed by the central genetic regulatory circuit BrlA→AbaA→WetA. Here, we report that WetA is a multi-functional regulator that couples spore differentiation and survival, and governs proper chemical development in Aspergillus flavus. The deletion of wetA results in the formation of conidia with defective cell walls and no intra-cellular trehalose, leading to reduced stress tolerance, a rapid loss of viability, and disintegration of spores. WetA is also required for normal vegetative growth, hyphal branching, and production of aflatoxins. Targeted and genome-wide expression analyses reveal that WetA exerts feedback control of brlA and that 5,700 genes show altered mRNA levels in the mutant conidia. Functional category analyses of differentially expressed genes in ΔwetA RNA-seq data indicate that WetA contributes to spore integrity and maturity by properly regulating the metabolic pathways of trehalose, chitin, α-(1,3)-glucan, ß-(1,3)-glucan, melanin, hydrophobins, and secondary metabolism more generally. Moreover, 160 genes predicted to encode transcription factors are differentially expressed by the absence of wetA, suggesting that WetA may play a global regulatory role in conidial development. Collectively, we present a comprehensive model for developmental control that bridges spore differentiation and survival in A. flavus.
[Mh] Termos MeSH primário: Aspergillus flavus/metabolismo
Proteínas Fúngicas/metabolismo
Regulação Fúngica da Expressão Gênica
Reprodução Assexuada
[Mh] Termos MeSH secundário: Aspergillus flavus/genética
Sobrevivência Celular
Proteínas Fúngicas/genética
Genes Fúngicos
Hifas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungal Proteins)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170629
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179571


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[PMID]:28614409
[Au] Autor:Hubot N; Lucas CH; Piraino S
[Ad] Endereço:Brussels Free University, Brussels, Belgium.
[Ti] Título:Environmental control of asexual reproduction and somatic growth of Aurelia spp. (Cnidaria, Scyphozoa) polyps from the Adriatic Sea.
[So] Source:PLoS One;12(6):e0178482, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Polyps of two moon jellyfish species, Aurelia coerulea and A. relicta, from two Adriatic Sea coastal habitats were incubated under multiple combinations of temperature (14, 21°C), salinity (24, 37 ppt) and food regime (9.3, 18.6, 27.9 µg C ind-1 week-1) to comparatively assess how these factors may influence major asexual reproduction processes in the two species. Both species exhibited a shared pattern of budding mode (Directly Budded Polyps: DBP; Stolonal Budded Polyps: SBP), with DBP favoured under low food supply (9.3 µg C ind -1 week-1) and low temperature (14°C), and SBP dominant under high temperature (21°C). However, A. coerulea showed an overall higher productivity than A. relicta, in terms of budding and podocyst production rates. Further, A. coerulea exhibited a wide physiological plasticity across different temperatures and salinities as typical adaptation to ecological features of transitional coastal habitats. This may support the hypothesis that the invasion of A. coerulea across coastal habitats worldwide has been driven by shellfish aquaculture, with scyphistoma polyps and resting stages commonly found on bivalve shells. On the contrary, A. relicta appears to be strongly stenovalent, with cold, marine environmental optimal preferences (salinity 37 ppt, T ranging 14-19°C), corroborating the hypothesis of endemicity within the highly peculiar habitat of the Mljet lake. By exposing A. relicta polyps to slightly higher temperature (21°C), a previously unknown developmental mode was observed, by the sessile polyp regressing into a dispersive, temporarily unattached and tentacle-less, non-feeding stage. This may allow A. relicta polyps to escape climatic anomalies associated to warming of surface layers and deepening of isotherms, by moving into deeper, colder layers. Overall, investigations on species-specific eco-physiological and ontogenetic potentials of polyp stages may contribute to clarify the biogeographic distribution of jellyfish and the phylogenetic relationships among evolutionary related sister clades.
[Mh] Termos MeSH primário: Adaptação Biológica
Reprodução Assexuada
Cifozoários/fisiologia
[Mh] Termos MeSH secundário: Animais
Ecossistema
Meio Ambiente
Oceanos e Mares
Filogenia
Cifozoários/crescimento & desenvolvimento
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170914
[Lr] Data última revisão:
170914
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170615
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0178482


  8 / 1435 MEDLINE  
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[PMID]:28594822
[Au] Autor:Blanc-Mathieu R; Perfus-Barbeoch L; Aury JM; Da Rocha M; Gouzy J; Sallet E; Martin-Jimenez C; Bailly-Bechet M; Castagnone-Sereno P; Flot JF; Kozlowski DK; Cazareth J; Couloux A; Da Silva C; Guy J; Kim-Jo YJ; Rancurel C; Schiex T; Abad P; Wincker P; Danchin EGJ
[Ad] Endereço:INRA, Université Côte d'Azur, CNRS, ISA, France.
[Ti] Título:Hybridization and polyploidy enable genomic plasticity without sex in the most devastating plant-parasitic nematodes.
[So] Source:PLoS Genet;13(6):e1006777, 2017 Jun.
[Is] ISSN:1553-7404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Root-knot nematodes (genus Meloidogyne) exhibit a diversity of reproductive modes ranging from obligatory sexual to fully asexual reproduction. Intriguingly, the most widespread and devastating species to global agriculture are those that reproduce asexually, without meiosis. To disentangle this surprising parasitic success despite the absence of sex and genetic exchanges, we have sequenced and assembled the genomes of three obligatory ameiotic and asexual Meloidogyne. We have compared them to those of relatives able to perform meiosis and sexual reproduction. We show that the genomes of ameiotic asexual Meloidogyne are large, polyploid and made of duplicated regions with a high within-species average nucleotide divergence of ~8%. Phylogenomic analysis of the genes present in these duplicated regions suggests that they originated from multiple hybridization events and are thus homoeologs. We found that up to 22% of homoeologous gene pairs were under positive selection and these genes covered a wide spectrum of predicted functional categories. To biologically assess functional divergence, we compared expression patterns of homoeologous gene pairs across developmental life stages using an RNAseq approach in the most economically important asexually-reproducing nematode. We showed that >60% of homoeologous gene pairs display diverged expression patterns. These results suggest a substantial functional impact of the genome structure. Contrasting with high within-species nuclear genome divergence, mitochondrial genome divergence between the three ameiotic asexuals was very low, signifying that these putative hybrids share a recent common maternal ancestor. Transposable elements (TE) cover a ~1.7 times higher proportion of the genomes of the ameiotic asexual Meloidogyne compared to the sexual relative and might also participate in their plasticity. The intriguing parasitic success of asexually-reproducing Meloidogyne species could be partly explained by their TE-rich composite genomes, resulting from allopolyploidization events, and promoting plasticity and functional divergence between gene copies in the absence of sex and meiosis.
[Mh] Termos MeSH primário: Variação Genética
Genoma Helmíntico
Hibridização Genética
Poliploidia
Reprodução Assexuada
Tylenchoidea/genética
[Mh] Termos MeSH secundário: Animais
Elementos de DNA Transponíveis
Genoma Mitocondrial
Polimorfismo Genético
Seleção Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA Transposable Elements)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170626
[Lr] Data última revisão:
170626
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170609
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pgen.1006777


  9 / 1435 MEDLINE  
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[PMID]:28545145
[Au] Autor:Höhn DP; Lucas CH; Thatje S
[Ad] Endereço:National Oceanography Centre Southampton, University of Southampton, Southampton, United Kingdom.
[Ti] Título:Respiratory response to temperature of three populations of Aurelia aurita polyps in northern Europe.
[So] Source:PLoS One;12(5):e0177913, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The benthic life stage (polyp or scyphistoma) of the bloom-forming jellyfish, Aurelia aurita (Linnaeus, 1759), also known as the moon jellyfish, contributes to the seasonal occurrence and abundance of medusa blooms via asexual reproduction. A. aurita is widely distributed in coastal areas in northern Europe, and one of the most studied jellyfish species. While the physiology of the visible medusa is largely understood, understanding of the physiology of the perennial benthic life-stage is scarce. To measure the physiological tolerance of A. aurita, the scyphistoma's temperature sensitivity across its distributional range was investigated. Respiration rates of polyps from three northern European locations exposed to 11 temperatures between 2 and 22°C were measured. There was a significant difference in respiration rate among the three polyp populations, which may reflect on differences in their thermal tolerance window. A critical temperature was reached at 14°C with the metabolic rate decreasing below and above that temperature. This pattern was less pronounced in the Norwegian population but polyps were able to survive, at least temporarily, those temperatures exceeding their natural range. While polyps collected from northern Norway, with a narrow environmental thermal window, displayed a low baseline metabolism with a Q10 value of 1.2, polyps from southern England and Scotland had Q10 values of 1.6 and 2.5, respectively. Differences in polyps' respiration rates across their distributional range suggest that populations have evolved adaptations to local environmental thermal conditions.
[Mh] Termos MeSH primário: Respiração
Cifozoários/fisiologia
[Mh] Termos MeSH secundário: Adaptação Fisiológica
Animais
Europa (Continente)
Reprodução Assexuada
Cifozoários/classificação
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170919
[Lr] Data última revisão:
170919
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170526
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0177913


  10 / 1435 MEDLINE  
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[PMID]:28427940
[Au] Autor:Igbalajobi OA; Yu JH; Shin KS
[Ad] Endereço:Department of Microbiology, Graduate School, Daejeon University, Daejeon 300-716, Republic of Korea.
[Ti] Título:Characterization of the rax1 gene encoding a putative regulator of G protein signaling in Aspergillus fumigatus.
[So] Source:Biochem Biophys Res Commun;487(2):426-432, 2017 May 27.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The filamentous fungus Aspergillus fumigatus is the major cause of life threatening invasive aspergillosis, and its small hydrophobic asexual spores (conidia) are the major infection agent. To better understand biology of A. fumigatus, we have characterized the rax1 gene encoding a putative regulator of G protein signaling (RGS). The deletion (Δ) of rax1 results in restricted colony growth and highly reduced number of conidia in A. fumigatus. Transcript levels of the three central activators of asexual development abaA, brlA, and wetA are significantly reduced in the Δrax1 mutant. However, the Δrax1 conidia, but not vegetative cells, are specifically resistant against H O stress. The Δrax1 conidia accumulate higher mRNA levels of sakA encoding a key MAP kinase for stress response. Moreover, the Δrax1 conidia contain over five-fold amount of trehalose, an osmolyte and protein/membrane protectant. Transmission electron microscopy analyses indicate that the Δrax1 conidia have the thicker melanized-outermost cell wall layer compared to those of wild-type. In summary, Rax1 positively controls growth and development, and modulates intracellular trehalose amount, cell wall melanin levels in conidia, and spore resistance to H O .
[Mh] Termos MeSH primário: Aspergillus fumigatus/fisiologia
Proteínas de Ligação ao GTP/metabolismo
Proteínas de Membrana/metabolismo
Reprodução Assexuada/fisiologia
Proteínas de Saccharomyces cerevisiae/metabolismo
Esporos Fúngicos/crescimento & desenvolvimento
Trealose/metabolismo
[Mh] Termos MeSH secundário: Transdução de Sinais
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Membrane Proteins); 0 (RAX1 protein, S cerevisiae); 0 (Saccharomyces cerevisiae Proteins); B8WCK70T7I (Trehalose); EC 3.6.1.- (GTP-Binding Proteins)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170422
[St] Status:MEDLINE



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