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1.
Immunity ; 51(1): 50-63.e5, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31174991

RESUMO

Chronic inflammatory diseases are associated with altered hematopoiesis that could result in neutrophilia and anemia. Here we report that genetic or chemical manipulation of different inflammasome components altered the differentiation of hematopoietic stem and progenitor cells (HSPC) in zebrafish. Although the inflammasome was dispensable for the emergence of HSPC, it was intrinsically required for their myeloid differentiation. In addition, Gata1 transcript and protein amounts increased in inflammasome-deficient larvae, enforcing erythropoiesis and inhibiting myelopoiesis. This mechanism is evolutionarily conserved, since pharmacological inhibition of the inflammasome altered erythroid differentiation of human erythroleukemic K562 cells. In addition, caspase-1 inhibition rapidly upregulated GATA1 protein in mouse HSPC promoting their erythroid differentiation. Importantly, pharmacological inhibition of the inflammasome rescued zebrafish disease models of neutrophilic inflammation and anemia. These results indicate that the inflammasome plays a major role in the pathogenesis of neutrophilia and anemia of chronic diseases and reveal druggable targets for therapeutic interventions.


Assuntos
Anemia/imunologia , Doenças dos Peixes/imunologia , Fator de Transcrição GATA1/metabolismo , Inflamassomos/metabolismo , Inflamação/imunologia , Neutrófilos/imunologia , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Animais , Animais Geneticamente Modificados , Caspase 1/genética , Caspase 1/metabolismo , Diferenciação Celular , Células Eritroides/citologia , Fator de Transcrição GATA1/genética , Regulação da Expressão Gênica no Desenvolvimento , Hematopoese , Humanos , Inflamassomos/genética , Células K562 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteólise , Proteínas de Peixe-Zebra/genética
2.
PLoS Biol ; 19(11): e3001455, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34748530

RESUMO

Several studies have revealed a correlation between chronic inflammation and nicotinamide adenine dinucleotide (NAD+) metabolism, but the precise mechanism involved is unknown. Here, we report that the genetic and pharmacological inhibition of nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme in the salvage pathway of NAD+ biosynthesis, reduced oxidative stress, inflammation, and keratinocyte DNA damage, hyperproliferation, and cell death in zebrafish models of chronic skin inflammation, while all these effects were reversed by NAD+ supplementation. Similarly, genetic and pharmacological inhibition of poly(ADP-ribose) (PAR) polymerase 1 (Parp1), overexpression of PAR glycohydrolase, inhibition of apoptosis-inducing factor 1, inhibition of NADPH oxidases, and reactive oxygen species (ROS) scavenging all phenocopied the effects of Nampt inhibition. Pharmacological inhibition of NADPH oxidases/NAMPT/PARP/AIFM1 axis decreased the expression of pathology-associated genes in human organotypic 3D skin models of psoriasis. Consistently, an aberrant induction of NAMPT and PARP activity, together with AIFM1 nuclear translocation, was observed in lesional skin from psoriasis patients. In conclusion, hyperactivation of PARP1 in response to ROS-induced DNA damage, fueled by NAMPT-derived NAD+, mediates skin inflammation through parthanatos cell death.


Assuntos
Inflamação/patologia , NAD/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Parthanatos , Poli(ADP-Ribose) Polimerases/metabolismo , Pele/patologia , Animais , Fator de Indução de Apoptose/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/patologia , Larva/metabolismo , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Parthanatos/efeitos dos fármacos , Parthanatos/genética , Poli Adenosina Difosfato Ribose/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteínas Secretadas Inibidoras de Proteinases/deficiência , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Psoríase/genética , Psoríase/patologia , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/metabolismo
3.
J Cell Sci ; 134(3)2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33419777

RESUMO

Fission yeast cells divide at a similar cell length with little variation about the mean. This is thought to be the result of a control mechanism that senses size and corrects for any deviations by advancing or delaying onset of mitosis. Gene deletions that advance cells into mitosis at a smaller size or delay cells entering mitosis have led to the identification of genes potentially involved in this mechanism. However, the molecular basis of this control is still not understood. In this work, we have screened for genes that when deleted increase the variability in size of dividing cells. The strongest candidate identified in this screen was mga2 The mga2 deletion strain shows a greater variation in cell length at division, with a coefficient of variation (CV) of 15-24%, while the wild-type strain has a CV of 5-8%. Furthermore, unlike wild-type cells, the mga2 deletion cells are unable to correct cell size deviations within one cell cycle. We show that the mga2 gene genetically interacts with nem1 and influences the nuclear membrane and the nuclear-cytoplasmic transport of CDK regulators.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Ciclo Celular/genética , Tamanho Celular , Mitose/genética , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genética
4.
J Cell Sci ; 130(24): 4144-4154, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29084823

RESUMO

Sexual differentiation in the fission yeast Schizosaccharomyces pombe promotes cell cycle arrest and extensive changes in gene expression, resulting in cell-to-cell fusion, the exchange of hereditary material and specialized cell division. These events are detrimental to the cell if they are triggered in inappropriate conditions, and therefore the decision to differentiate must be precisely controlled. Here, we investigated the role of the RNA-binding protein Zfs1 in this process by identifying its targets and characterizing novel post-translational regulatory mechanisms. We found that Zfs1 negatively regulates the G1 cyclin Puc1, and deregulated Puc1 levels inhibit differentiation in the zfs1Δ mutant. We also found that Zfs1 undergoes phosphorylation, which is stimulated upon nitrogen depletion or inhibition of the TOR pathway. Phosphorylation of Zfs1 modulates accumulation of Puc1 and plays an important role in the response of the cell to sexual differentiation signals. We propose that Zfs1 functions as an integrator of nutrient information to modulate sexual differentiation, contributing to the establishment of the differentiation-activating threshold.


Assuntos
Ciclinas/genética , Proteínas Nucleares/genética , Proteínas de Schizosaccharomyces pombe/genética , Schizosaccharomyces/genética , Diferenciação Sexual/genética , Proteínas de Ciclo Celular/genética , Divisão Celular/genética , Regulação Fúngica da Expressão Gênica , Fosforilação , Proteínas de Ligação a RNA , Schizosaccharomyces/crescimento & desenvolvimento
5.
Nature ; 498(7452): 51-9, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23739423

RESUMO

Since the 2007 Intergovernmental Panel on Climate Change Fourth Assessment Report, new observations of ice-sheet mass balance and improved computer simulations of ice-sheet response to continuing climate change have been published. Whereas Greenland is losing ice mass at an increasing pace, current Antarctic ice loss is likely to be less than some recently published estimates. It remains unclear whether East Antarctica has been gaining or losing ice mass over the past 20 years, and uncertainties in ice-mass change for West Antarctica and the Antarctic Peninsula remain large. We discuss the past six years of progress and examine the key problems that remain.


Assuntos
Mudança Climática/estatística & dados numéricos , Camada de Gelo , Incerteza , Ar , Regiões Antárticas , Simulação por Computador , Groenlândia , Neve , Temperatura
6.
Int J Phytoremediation ; 20(10): 1033-1042, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30095313

RESUMO

Phytoextraction is a green technique for the removal of soil contaminants by plants uptake with the subsequent elimination of the generated biomass. The halophytic plant Suaeda vera Forssk. ex J.F.Gmel. is an native Mediterranean species able to tolerate and accumulate salts and heavy metals in their tissues. The objective of this study was to explore the potential use of S. vera for soil metal phytoextraction and to assess the impact of different chelating agents such as natural organic acids (oxalic acid [OA], citric acid [CA]), amino acids (AA) and Pseudomonas fluorescens bacteria (PFB) on the metal uptake and translocation. After 12 months, the highest accumulation of Cu was observed in the root/stem of PFB plots (17.62/8.19 mg/kg), in the root/stem of CA plots for Zn (31.16/23.52 mg/kg) and in the root of OA plots for Cr (10.53 mg/kg). The highest accumulation of metals occurred in the roots (27.33-50.76 mg/kg). Zn was the metal that accumulated at the highest rates in most cases. The phytoextraction percentages were higher for Cu and Zn (∼2%) with respect to Cr (∼1%). The percentages of metal removal from soil indicate the need to monitor soil properties, to recognize the influence of each treatment and to increase the concentration of bioavailable metals by the use of agricultural management practices aimed at promoting plant growth.


Assuntos
Chenopodiaceae , Metais Pesados , Pseudomonas fluorescens , Poluentes do Solo , Aminoácidos , Biodegradação Ambiental , Quelantes/química , Ácido Cítrico/química , Ácido Oxálico , Solo , Zinco
7.
J Sci Food Agric ; 98(14): 5534-5540, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29691879

RESUMO

BACKGROUND: In the last decade, diseases of bacterial origin in onions have increased and this has led to significant losses in production. These diseases are currently observed in both the Old and New Worlds. The present study aimed to evaluate whether the irrigation method influences the incidence of diseases of bacterial origin. RESULTS: In cases where the inoculum was natural, the initial incidence of soft bacterial rot did not manifest in any treatment in the first year, whereas, at the end of the conservation period, all treatments had increased incidences of infection. Sprinkler irrigation (8%) was statistically differentiated from the other treatments, for which the final incidence was similar (4.5%). For all irrigation treatments, the final incidence of bacterial soft rot decreased or remained stable towards the end of the cycle, with the exception of sprinkler irrigation in 2015, which increased. CONCLUSION: From the results of the present study, it can be inferred that the irrigation method does have an influence on the incidence of diseases of bacterial origin in the post-harvest stage for onions. © 2018 Society of Chemical Industry.


Assuntos
Irrigação Agrícola/métodos , Água Doce/microbiologia , Cebolas/microbiologia , Doenças das Plantas/microbiologia , Cebolas/crescimento & desenvolvimento
8.
Energy Fuels ; 38(4): 3407-3416, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38380112

RESUMO

The goal of this work was to study the miscibility, thermal stability, thermomechanical properties, and temperature regulation performance of paraffin wax/bitumen blends for their potential use in solar thermal energy storage applications. Results indicated that these blends present a suitable thermal stability, and their thermomechanical properties are strongly dependent on composition, developed microstructure, and temperature. Among all paraffin wax concentrations studied, the blend containing 40 wt % paraffin wax displays enhanced binder elastic properties together with lower thermal susceptibility compared to base bitumen. In addition, this binder also presents improved thermal properties (thermal conductivity and specific heat capacity) and still maintains a high crystallinity, thereby retaining a large enough latent heat to be used for thermal energy storage. Thus, results from the temperature regulation test, which was conducted by subjecting the sample to simulated solar irradiation at a constant radiant flux density, provide a higher latent heat thermoregulation index value than other microencapsulated phase change materials systems. Therefore, it can be stated that paraffin wax/bitumen blends are promising base materials to formulate form-stable products for thermal energy storage applications for thermoregulation purposes.

9.
Heliyon ; 10(1): e23852, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192796

RESUMO

The chemo-morphological properties of soils on ancient landforms (quarzitic pliocene alluvial fans, pleistocene terraces), namely "rañizos", on middle-high mountains (Eastern-Central System, Iberian Peninsula, Rio Negro, Cogolludo) were investigated. Several properties were analyzed by standard procedures. A detailed soil diagnostics and classification on "rañizos" were done, unlike those widely studied on "rañas" (similar landform), by identifying parallel pedogenetic processes in both formations. The genetic and geographic features of Alfisols, Ultisols and Inceptisols are closely related to the nature of their parent materials, based on quartzite and quartz conglomerates, sometimes with an arkosic matrix, red shale, polygenic gravels and pebbles. Soil features were determined by genuine soil-forming inherent lithological rock properties. Other driving factors were flat topography and enough soil formation time to allow intense pedogenesis. The main soil-forming processes were intense weathering, clay enrichment horizons with illuviation, red color caused by iron oxide dehydration and signs of pseudogleyzation processes. Such pedological formations can be considered endemisms; that is, "rare" soils and, up to a point, "relict". The soil reaction is acid/slightly acid with low base saturation. Despite lying on mountains, soils are characterized by moderate-low organic matter content. Soil conditions and climate provide good vine production requirements despite acidity levels. A common feature of all Rio Negro soils is the presence of gravel (size up to 3-5 cm), which is evenly distributed on arable layers. The results can be used to assess vineyard soil use in a potential Pago (Protected Denomination of Origin) and to extend the database of vineyard soils from poorly studied Mediterranean continental mountain regions.

10.
Polymers (Basel) ; 14(14)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35890655

RESUMO

Oil-in-water bitumen emulsions stabilized by biobased surfactants such as lignin are in line with the current sustainable approaches of the asphalt industry involving bitumen emulsions for reduced temperature asphalt technologies. With this aim, three lignins, derived from the kraft pulping and bioethanol industries, were chemically modified via the Mannich reaction to be used as cationic emulsifiers. A comprehensive chemical characterization was conducted on raw lignin-rich products, showing that the kraft sample presents a higher lignin concentration and lower molecular weight. Instead, bioethanol-derived samples, with characteristics of non-woody lignins, present a high concentration of carbohydrate residues and ashes. Lignin amination was performed at pH = 10 and 13, using tetraethylene pentamine and formaldehyde as reagents at three different stoichiometric molar ratios. The emulsification ability of such cationic surfactants was firstly studied on prototype silicone oil-in-water emulsions, attending to their droplet size distribution and viscous behavior. Among the synthetized surfactants, cationic kraft lignin has shown the best emulsification performance, being used for the development of bitumen emulsions. In this regard, cationic kraft lignin has successfully stabilized oil-in-water emulsions containing 60% bitumen using small surfactant concentrations, between 0.25 and 0.75%, which was obtained at pH = 13 and reagent molar ratios between 1/7/7 and 1/28/28 (lignin/tetraethylene pentamine/formaldehyde).

11.
Polymers (Basel) ; 13(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34451242

RESUMO

Lignin is an abundant biopolymer with potential value-added applications that depend on biomass source and fractioning method. This work explores the use as emulsifiers of three native lignin-rich product coming from industrial bioethanol production and alkali or Kraft pulping. In addition to their distinctive characteristics, the different molecular organization induced by emulsification pH is expected to interact in various ways at the water-oil interface of the emulsion droplets. Initially, model oil-in-water (O/W) emulsions of a silicone oil will be studied as a function of lignin source, disperse phase concentration and emulsification pH. Once stablished the effect of such variables, emulsion formulations of three potential bitumen rejuvenators (waste vegetable cooking oil, recycled lubricating oil and a 160/220 penetration range soft bitumen). Droplet size distribution, Z-potential and viscous tests conducted on model emulsions have shown that emulsification pH strongly affects stabilization ability of the lignins tested. Regarding bitumen rejuvenators, lignin emulsification capability will be affected by surfactant source, pH and, additionally, by the dispersed phase characteristics. Lower Z-potential values shown by KL at pH 9 and 11 seem to facilitate emulsification of the less polar disperse phases formed by RLUB and bitumen. In any case, lower particle size and higher yield stress values were found for both bioethanol-derived lignins emulsifying RVO and RLUB at pH 13, which are expected to exhibit a longer stability.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32867215

RESUMO

The mineralogical and geochemical patterns of calcareous vineyard soils located in Alcubillas (La Mancha, Central Spain) have been evaluated; also their variability has been studied. The information provided by this study supports the assessment of geochemical spatial variability, the origin of these soils, their elements and the factors that control their distribution. The presence of quartz, calcite, feldspar and, in particular, illite and kaolinite is due to their inheritance from surrounding lithologies (and pedological processes), which mostly include limestones, marls and other sedimentary rocks, as well as metasedimentary rocks of Hercynian origin. Furthermore, since the presence and accumulation of certain trace elements in vineyard soils is a relevant global hazard (in particular with respect to wine production quality), the spatial distributions of Ba, Cr, Cu, Pb, Rb, Sr, V and Zr (carried out using geostatistical techniques and geometry-based interpolation methods) were investigated in order to determine the origin of these trace elements. The presence of these elements can be interpreted as being due to geogenic, pedogenic and, in certain cases, anthropic influences. The nature of certain agricultural practices, including the use of fertilizers, phytosanitary products and machinery, could explain the local increases in some trace element contents.


Assuntos
Poluentes do Solo , Solo , Oligoelementos , Monitoramento Ambiental , Fazendas , Humanos , Poluentes do Solo/análise , Espanha , Oligoelementos/análise
13.
Dev Comp Immunol ; 108: 103666, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32126244

RESUMO

Psoriasis is a skin inflammatory disorder that affects 3% of the human population. Although several therapies based on the neutralization of proinflammatory cytokines have been used with relative success, additional treatments are required. The in silico analysis of gene expression data of psoriasis lesional skin and an analysis of vitamin B6 metabolites in the sera of psoriasis patients point to altered vitamin B6 metabolism at both local and systemic levels. Functional studies showed that vitamin B6 vitamers reduced skin neutrophil infiltration, oxidative stress and Nfkb activity in two zebrafish models of skin inflammation. Strikingly, inhibition of glycogen phosphorylase L (Pygl) and glucose-6-phosphate dehydrogenase (G6pd), two vitamin B6-regulated enzymes, alleviated oxidative-stress induced inflammation in zebrafish skin inflammation models. Despite the central role of G6pd in antioxidant defenses, the results of the study demonstrate that glycogen stores and G6pd fuel NADPH oxidase to promote skin inflammation, revealing novel targets for the treatment of skin inflammatory disorders.


Assuntos
Glucosefosfato Desidrogenase/metabolismo , Glicogênio Fosforilase Hepática/metabolismo , Psoríase/imunologia , Vitamina B 6/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Biópsia , Conjuntos de Dados como Assunto , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Glucosefosfato Desidrogenase/antagonistas & inibidores , Glucosefosfato Desidrogenase/genética , Glicogênio/metabolismo , Glicogênio Fosforilase Hepática/antagonistas & inibidores , Glicogênio Fosforilase Hepática/genética , Células HaCaT , Humanos , Microscopia Intravital , NADPH Oxidases/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/imunologia , Psoríase/sangue , Psoríase/tratamento farmacológico , Psoríase/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Pele/diagnóstico por imagem , Pele/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Vitamina B 6/sangue , Peixe-Zebra
14.
Dev Comp Immunol ; 105: 103583, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31862296

RESUMO

The zebrafish has become an excellent model for the study of inflammation and immunity. Its unique advantages for in vivo imaging and gene and drug screening have allowed the visualization of dual oxidase 1 (Duox1)-derived hydrogen peroxide (H2O2) tissue gradients and its crosstalk with neutrophil infiltration to inflamed tissue. Thus, it has been shown that H2O2 directly recruits neutrophils via the Src-family tyrosine kinase Lyn and indirectly by the activation of several signaling pathways involved in inflammation, such as nuclear factor κB (NF-κB), mitogen activated kinases and the transcription factor AP1. In addition, this model has also unmasked the unexpected ability of H2O2 to induce the expression of the gene encoding the key neutrophil chemoattractant CXC chemokine ligand 8 by facilitating the accessibility of transcription factors to its promoter through histone covalent modifications. Finally, zebrafish models of psoriasis have shown that a H2O2/NF-κB/Duox1 positive feedback inflammatory loop operates in this chronic inflammatory disorder and that pharmacological inhibition of Duox1, but not of downstream mediators, inhibits inflammation and restores epithelial homeostasis. Therefore, these results have pointed out DUOX1 and H2O2 as therapeutic targets for the treatment of skin inflammatory disorders, such as psoriasis.


Assuntos
Peróxido de Hidrogênio/metabolismo , Inflamação/imunologia , Neutrófilos/imunologia , Psoríase/imunologia , Peixe-Zebra/imunologia , Animais , Oxidases Duais/genética , Oxidases Duais/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Humanos , Interleucina-8/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Cicatrização
15.
ACS Synth Biol ; 8(2): 358-370, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30624905

RESUMO

MicroRNAs (miRNAs), small RNA molecules of 20-24 nts, have many features that make them useful tools for gene expression regulation-small size, flexible design, target predictability, and action at a late stage of the gene expression pipeline. In addition, their role in fine-tuning gene expression can be harnessed to increase robustness of synthetic gene networks. In this work, we apply a synthetic biology approach to characterize miRNA-mediated gene expression regulation in the unicellular green alga Chlamydomonas reinhardtii. This characterization is then used to build tools based on miRNAs, such as synthetic miRNAs, miRNA-responsive 3'UTRs, miRNA decoys, and self-regulatory loops. These tools will facilitate the engineering of gene expression for new applications and improved traits in this alga.


Assuntos
Chlamydomonas reinhardtii/metabolismo , MicroRNAs/metabolismo , Regiões 3' não Traduzidas/genética , Chlamydomonas reinhardtii/genética , Regulação da Expressão Gênica , Genes Sintéticos/genética , MicroRNAs/genética
16.
Sci Rep ; 9(1): 11091, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366981

RESUMO

The unicellular green alga Chlamydomonas reinhardtii is evolutionarily divergent from higher plants, but has a fully functional silencing machinery including microRNA (miRNA)-mediated translation repression and mRNA turnover. However, distinct from the metazoan machinery, repression of gene expression is primarily associated with target sites within coding sequences instead of 3'UTRs. This feature indicates that the miRNA-Argonaute (AGO) machinery is ancient and the primary function is for post transcriptional gene repression and intermediate between the mechanisms in the rest of the plant and animal kingdoms. Here, we characterize AGO2 and 3 in Chlamydomonas, and show that cytoplasmically enriched Cr-AGO3 is responsible for endogenous miRNA-mediated gene repression. Under steady state, mid-log phase conditions, Cr-AGO3 binds predominantly miR-C89, which we previously identified as the predominant miRNA with effects on both translation repression and mRNA turnover. In contrast, the paralogue Cr-AGO2 is nuclear enriched and exclusively binds to 21-nt siRNAs. Further analysis of the highly similar Cr-AGO2 and Cr-AGO 3 sequences (90% amino acid identity) revealed a glycine-arginine rich N-terminal extension of ~100 amino acids that, given previous work on unicellular protists, may associate AGO with the translation machinery. Phylogenetic analysis revealed that this glycine-arginine rich N-terminal extension is present outside the animal kingdom and is highly conserved, consistent with our previous proposal that miRNA-mediated CDS-targeting operates in this green alga.


Assuntos
Proteínas Argonautas/genética , Chlamydomonas reinhardtii/genética , Regulação da Expressão Gênica de Plantas/genética , Expressão Gênica/genética , MicroRNAs/genética , Regiões 3' não Traduzidas/genética , Evolução Biológica , Filogenia , Interferência de RNA/fisiologia , RNA Mensageiro/genética , RNA Interferente Pequeno/genética
17.
ACS Synth Biol ; 7(9): 2074-2086, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30165733

RESUMO

Microalgae are regarded as promising organisms to develop innovative concepts based on their photosynthetic capacity that offers more sustainable production than heterotrophic hosts. However, to realize their potential as green cell factories, a major challenge is to make microalgae easier to engineer. A promising approach for rapid and predictable genetic manipulation is to use standardized synthetic biology tools and workflows. To this end we have developed a Modular Cloning toolkit for the green microalga Chlamydomonas reinhardtii. It is based on Golden Gate cloning with standard syntax, and comprises 119 openly distributed genetic parts, most of which have been functionally validated in several strains. It contains promoters, UTRs, terminators, tags, reporters, antibiotic resistance genes, and introns cloned in various positions to allow maximum modularity. The toolkit enables rapid building of engineered cells for both fundamental research and algal biotechnology. This work will make Chlamydomonas the next chassis for sustainable synthetic biology.


Assuntos
Chlamydomonas reinhardtii/metabolismo , Fotossíntese , Plasmídeos/metabolismo , Biologia Sintética/métodos , Biotecnologia , Chlamydomonas reinhardtii/genética , Expressão Gênica , Genes Reporter/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Plasmídeos/genética , Regiões Promotoras Genéticas
18.
Environ Sci Pollut Res Int ; 23(7): 6055-61, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25801370

RESUMO

Mercury contents in soil and olive tree leaves have been studied in 69 plots around three different source areas of this element in Spain: Almadén (Ciudad Real), Flix (Tarragona) and Jódar (Jaén). Almadén was the world's largest cinnabar (HgS) mining district and was active until 2003, Flix is the oldest Spanish chlor-alkali plant (CAP) and has been active from 1898 to the present day and Jódar is a decommissioned CAP that was active for 14 years (1977-1991). Total mercury contents have been measured by high-frequency modulation atomic absorption spectrometry with Zeeman effect (ZAAS-HFM) in the soils and olive tree leaves from the three studied areas. The average soil contents range from 182 µg kg(-1) in Flix to 23,488 µg kg(-1) in Almadén, while the average leaf content ranges from 161 µg kg(-1) in Jódar to 1213 µg kg(-1) in Almadén. Despite the wide range of data, a relationship between soil-leaf contents has been identified: in Almadén and Jódar, multiplicative (bilogarithmic) models show significant correlations (R = 0.769 and R = 0.484, respectively). Significant correlations were not identified between soil and leaf contents in Flix. The continuous activity of the Flix CAP, which remains open today, can explain the different uptake patterns for mercury, which is mainly atmospheric in origin, in comparison to the other two sites, where activity ceased more than 10 years ago and only soil uptake patterns based on the Michaelis-Menten enzymatic model curve are observed.


Assuntos
Monitoramento Ambiental , Mercúrio/análise , Olea/química , Poluentes do Solo/análise , Compostos de Mercúrio , Mineração , Folhas de Planta/química , Plantas , Solo/química , Espanha
19.
Dev Comp Immunol ; 49(1): 44-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25445910

RESUMO

In recent years zebrafish has emerged as an excellent model for studying the Cxcl8 signaling pathway in inflammation elicited upon tissue damage or infection. Zebrafish has two true homologs of mammalian CXCL8, named Cxcl8-l1 and Cxcl8-l2. Previously, we have shown that in wound-associated inflammation, these chemokines are up-regulated and are relevant for neutrophil recruitment. In infections, no such knowledge is available as most studies performed on this subject in zebrafish have mainly focused on Cxcl8-l1 even though Cxcl8-l2 shares higher homology with human CXCL8. In this study, we aimed to address the biological function of both zfCxcl8s in infection to improve our understanding of their respective roles under different inflammatory conditions. Gene expression analysis first confirmed that both Cxcl8-l1 and l2 are induced upon infection or in PAMP-elicited inflammatory processes. In addition, we also found that cxcl8-deficient larvae show higher susceptibility to Salmonella enterica serovar Typhimurium (S. Typhimurium) infection, reduced neutrophil recruitment to the infection site assayed in the line Tg(mpx:gfp), and decreased bacterial clearance. These data indicate that both zebrafish Cxcl8s play important roles in neutrophil recruitment and in the inflammatory response elicited upon infection or tissue damage, suggesting that even though the divergence of lower vertebrates and humans from a common ancestor occurred about 450 millions years ago, the basic principles of neutrophil recruitment are apparently conserved in all vertebrates.


Assuntos
Resistência à Doença/imunologia , Interleucina-8/imunologia , Salmonella typhimurium/imunologia , Proteínas de Peixe-Zebra/imunologia , Peixe-Zebra/imunologia , Animais , Resistência à Doença/genética , Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Interações Hospedeiro-Patógeno/imunologia , Interleucina-8/genética , Interleucina-8/metabolismo , Larva/genética , Larva/imunologia , Larva/microbiologia , Microscopia de Fluorescência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Salmonella typhimurium/fisiologia , Análise de Sobrevida , Peixe-Zebra/genética , Peixe-Zebra/microbiologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
20.
Fertil Steril ; 79(6): 1409-15, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12798890

RESUMO

OBJECTIVE: To compare the mRNA expression of vascular endothelial growth factor (VEGF) 121 and 165 isoforms and thrombospondin-1 (TSP-1) after raloxifene, 17beta-E(2), and P administration in cultured Ishikawa cells. DESIGN: Prospective basic research study. SETTING: Jones Institute for Reproductive Medicine, Eastern Virginia Medical School, Norfolk, Virginia. PATIENT(S): None. INTERVENTION(S): Ishikawa cells were cultured in vitro. Raloxifene, 17beta-E(2), and P at concentrations of 0.01, 0.1, and 1.0 microM were added to confluent cells. MAIN OUTCOME MEASURES: The VEGF 121 and 165 isoforms and TSP-1 mRNA expression from treated Ishikawa cells were analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULT(S): 17beta-Estradiol increased both VEGF 121 and 165 mRNA compared to control. Raloxifene did not increase either VEGF 121 or 165 mRNA above control values. Progesterone at all concentrations did not increase VEGF 121 isoform mRNA, whereas VEGF 165 isoform was minimally increased by P at the lowest concentration. Progesterone and raloxifene increased TSP-1 mRNA expression. 17beta-Estradiol did not stimulate TSP-1 mRNA expression at any concentration. CONCLUSION(S): Raloxifene did not stimulate VEGF 121 and 165, whereas it increased TSP-1 mRNA synthesis in Ishikawa cells. Our hypothesis is that raloxifene's lack of endometrial stimulation may be partly mediated by an antiangiogenic effect.


Assuntos
Inibidores da Angiogênese/farmacologia , Fatores de Crescimento Endotelial/genética , Estradiol/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Linfocinas/genética , Progesterona/farmacologia , Cloridrato de Raloxifeno/farmacologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Trombospondina 1/genética , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Estudos Prospectivos , Isoformas de Proteínas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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