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1.
Nat Prod Res ; 37(14): 2446-2450, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35236187

RESUMO

Copaifera langsdorffii Desf. is recognised as one of most famous medicinal and economic species of Copaiba, occurring in several distinct biomes. An untargeted metabolomic approach was used to evaluate the chemical variability of C. langsdorffii from contrasting climates biomes (Atlantic Rainflorest and the semiarid Cerrado). Metabolomic analysis enabled the identification of 11 compounds, including glycosylated flavonoids and galloylquinic acid derivatives. Multivariate analysis highlighted that Cerrado population had a significantly higher concentrations of galloylquinic acid derivatives in comparison to the rainforest biome. Meanwhile, Atlantic Rainforest populations presented higher content of flavonols. Semiarid biome, reduced the concentration of flavonoids, mainly concerning quercetin and kaempferol derivatives, however, in this biome flavonoids were more diverse. Both chemical classes presented relevance to be used as geographical origin chemical markers by qualitative and quantitative features.


Assuntos
Fabaceae , Folhas de Planta , Folhas de Planta/química , Flavonoides/química , Quercetina/análise , Extratos Vegetais/química , Fabaceae/química
2.
Front Plant Sci ; 12: 642758, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33643370

RESUMO

The correct development of a diploid sporophyte body and a haploid gametophyte relies on a strict coordination between cell divisions in space and time. During plant reproduction, these divisions have to be temporally and spatially coordinated with cell differentiation processes, to ensure a successful fertilization. Armadillo BTB Arabidopsis protein 1 (ABAP1) is a plant exclusive protein that has been previously reported to control proliferative cell divisions during leaf growth in Arabidopsis. Here, we show that ABAP1 binds to different transcription factors that regulate male and female gametophyte differentiation, repressing their target genes expression. During male gametogenesis, the ABAP1-TCP16 complex represses CDT1b transcription, and consequently regulates microspore first asymmetric mitosis. In the female gametogenesis, the ABAP1-ADAP complex represses EDA24-like transcription, regulating polar nuclei fusion to form the central cell. Therefore, besides its function during vegetative development, this work shows that ABAP1 is also involved in differentiation processes during plant reproduction, by having a dual role in regulating both the first asymmetric cell division of male gametophyte and the cell differentiation (or cell fusion) of female gametophyte.

3.
An Acad Bras Cienc ; 92(suppl 2): e20190047, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33084756

RESUMO

This study aimed to investigate antigenotoxicity and antioxidant potential of extract, fractions and vitexin from C. antisyphiliticus. Methanolic extract was fractionated through solvents of increasing polarity. The composition of extracts and fractions were evaluated through phytochemical screening. Micronucleus test was performed in mice to evaluate the antigenotoxicity. Antioxidant activity was measured using the assay 1,1-diphenyl-2-picrylhydrazyl (DPPH), iron ion chelating, thiobarbituric acid assay and nitric oxide scavenging. Treatment with extract, fractions and vitexin did not produce an increase in Micronucleus mean values. However, Micronucleus (MN) mean values decreased in relation to control. methanolic extract presented antioxidant potential for DPPH (81%), iron ion chelating (77.8%), Thiobarbituric Acid (TBARS) (32.49%) and Nitric Oxide (NO) (80.97%). Ethyl acetate fraction showed the highest antioxidant activity (65.46%). The vitexin showed a Inhibitory Concentration (IC50) of DPPH value smaller in relation to control. Vitexin flavonoid was detected by High Performance Liquid Chromatography (HPLC), infrared spectrometry and nuclear magnetic resonance. It can be inferred that methanolic extract, fraction ethyl acetate and vitexin isolated from C. antisyphiliticus is endowed with antigenotoxic and antioxidant potential.


Assuntos
Croton , Animais , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Camundongos , Compostos Fitoquímicos , Extratos Vegetais/farmacologia
4.
Fungal Biol ; 124(5): 263-272, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32389288

RESUMO

Fungi sense light and utilize it as a source of environmental information to prepare against many stressful conditions in nature. In this study, Metarhizium robertsii was grown on: 1) potato dextrose agar medium (PDA) in the dark (control); 2) under nutritive stress in the dark; and 3) PDA under continuous (A) white light; (B) blue light lower irradiance = LI; (C) blue light higher irradiance = HI; (D) green light; and (E) red light. Conidia produced under these treatments were tested against osmotic stress and UV radiation. In addition, a suite of genes usually involved in different stress responses were selected to study their expression patterns. Conidia produced under nutritive stress in the dark were the most tolerant to both osmotic stress and UV radiation, and the majority of their stress- and virulence-related genes were up-regulated. For osmotic stress tolerance, conidia produced under white, blue LI, and blue HI lights were the second most tolerant, followed by conidia produced under green light. Conidia produced under red light were the least tolerant to osmotic stress and less tolerant than conidia produced on PDA medium in the dark. For UV tolerance, conidia produced under blue light LI were the second most tolerant to UV radiation, followed by the UV tolerances of conidia produced under white light. Conidia produced under blue HI, green, and red lights were the least UV tolerant and less tolerant than conidia produced in the dark. The superoxide dismutases (sod1 and sod2), photolyases (6-4phr and CPDphr), trehalose-phosphate synthase (tps), and protease (pr1) genes were highly up-regulated under white light condition, suggesting a potential role of these proteins in stress protection as well as virulence after fungal exposure to visible spectrum components.


Assuntos
Desoxirribodipirimidina Fotoliase , Regulação Fúngica da Expressão Gênica , Luz , Metarhizium , Esporos Fúngicos , Regulação Fúngica da Expressão Gênica/efeitos da radiação , Metarhizium/crescimento & desenvolvimento , Metarhizium/efeitos da radiação , Pressão Osmótica , Esporos Fúngicos/efeitos da radiação , Raios Ultravioleta
5.
Fungal Biol ; 124(5): 273-288, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32389289

RESUMO

Osmotic stress induced by high solute concentration can prevent fungal metabolism and growth due to alterations in properties of the cytosol, changes in turgor, and the energy required to synthesize and retain compatible solutes. We used germination to quantify tolerance/sensitivity to the osmolyte KCl (0.1-4.5 M, in 0.1 M increments) for 71 strains (40 species) of ecologically diverse fungi. These include 11 saprotrophic species (17 strains, including two xerophilic species), five mycoparasitic species (five strains), six plant-pathogenic species (13 strains), and 19 entomopathogenic species (36 strains). A dendrogram obtained from cluster analyses, based on KCl inhibitory concentrations 50 % and 90 % calculated by Probit Analysis, revealed three groups of fungal isolates accordingly to their osmotolerance. The most-osmotolerant group (Group 3) contained the majority of saprotrophic fungi, and Aspergillus niger (F19) was the most tolerant. The highly xerophilic Aspergillus montevidense and Aspergillus pseudoglaucus were the second- and third-most tolerant species, respectively. All Aspergillus and Cladosporium species belonged to Group 3, followed by the entomopathogens Colletotrichum fioriniae, Simplicillium lanosoniveum, and Trichothecium roseum. Group 2 exhibited a moderate osmotolerance, and included plant-pathogens such as Colletotrichum and Fusarium, mycoparasites such as Clonostachys spp, some saprotrophs such as Mucor and Penicillium spp., and some entomopathogens such as Isaria, Lecanicillium, Mariannaea, Simplicillium, and Torrubiella. Group 1 contained the osmo-sensitive strains: the rest of the entomopathogens and the mycoparasitic Gliocladium and Trichoderma. Although stress tolerance did not correlate with their primary ecological niche, classification of these 71 fungal strains was more closely aligned with their ecology than with their phylogenetic relatedness. We discuss the implications for both microbial ecology and fungal taxonomy.


Assuntos
Ecossistema , Fungos , Tolerância ao Sal , Fungos/classificação , Fungos/fisiologia , Filogenia
6.
PeerJ ; 7: e6080, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30648010

RESUMO

Miniature inverted-repeat transposable elements (MITEs) have been associated with genic regions in plant genomes and may play important roles in the regulation of nearby genes via recruitment of small RNAs (sRNA) to the MITEs loci. We identified eight families of MITEs in the sugarcane genome assembly with MITE-Hunter pipeline. These sequences were found to be upstream, downstream or inserted into 67 genic regions in the genome. The position of the most abundant MITE (Stowaway-like) in genic regions, which we call AddIn-MITE, was confirmed in a WD40 gene. The analysis of four monocot species showed conservation of the AddIn-MITE sequence, with a large number of copies in their genomes. We also investigated the conservation of the AddIn-MITE' position in the WD40 genes from sorghum, maize and, in sugarcane cultivars and wild Saccharum species. In all analyzed plants, AddIn-MITE has located in WD40 intronic region. Furthermore, the role of AddIn-MITE-related sRNA in WD40 genic region was investigated. We found sRNAs preferentially mapped to the AddIn-MITE than to other regions in the WD40 gene in sugarcane. In addition, the analysis of the small RNA distribution patterns in the WD40 gene and the structure of AddIn-MITE, suggests that the MITE region is a proto-miRNA locus in sugarcane. Together, these data provide insights into the AddIn-MITE role in Andropogoneae grasses.

7.
Noncoding RNA ; 4(4)2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297664

RESUMO

Long non-coding RNAs (lncRNAs) are involved in multiple regulatory pathways and its versatile form of action has disclosed a new layer in gene regulation. LncRNAs have their expression levels modulated during plant development, and in response to stresses with tissue-specific functions. In this study, we analyzed lncRNA from leaf samples collected from the legume Copaifera langsdorffii Desf. (copaíba) present in two divergent ecosystems: Cerrado (CER; Ecological Station of Botanical Garden in Brasília, Brazil) and Atlantic Rain Forest (ARF; Rio de Janeiro, Brazil). We identified 8020 novel lncRNAs, and they were compared to seven Fabaceae genomes and transcriptomes, to which 1747 and 2194 copaíba lncRNAs were mapped, respectively, to at least one species. The secondary structures of the lncRNAs that were conserved and differentially expressed between the populations were predicted using in silico methods. A few selected lncRNA were confirmed by RT-qPCR in the samples from both biomes; Additionally, the analysis of the lncRNA sequences predicted that some might act as microRNA (miRNA) targets or decoys. The emerging studies involving lncRNAs function and conservation have shown their involvement in several types of biotic and abiotic stresses. Thus, the conservation of lncRNAs among Fabaceae species considering their rapid turnover, suggests they are likely to have been under functional conservation pressure. Our results indicate the potential involvement of lncRNAs in the adaptation of C. langsdorffii in two different biomes.

8.
Trends Plant Sci ; 23(8): 731-747, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29934041

RESUMO

Oscillation in energy levels is widely variable in dividing and differentiated cells. To synchronize cell proliferation and energy fluctuations, cell cycle-related proteins have been implicated in the regulation of mitochondrial energy-generating pathways in yeasts and animals. Plants have chloroplasts and mitochondria, coordinating the cell energy flow. Recent findings suggest an integrated regulation of these organelles and the nuclear cell cycle. Furthermore, reports indicate a set of interactions between the cell cycle and energy metabolism, coordinating the turnover of proteins in plants. Here, we discuss how cell cycle-related proteins directly interact with energy metabolism-related proteins to modulate energy homeostasis and cell cycle progression. We provide interfaces between cell cycle and energy metabolism-related proteins that could be explored to maximize plant yield.


Assuntos
Ciclo Celular , Metabolismo Energético , Plantas/metabolismo , Núcleo Celular/metabolismo , Proliferação de Células , Cloroplastos/metabolismo , Mitocôndrias/metabolismo , Fotossíntese , Proteólise
9.
Fungal Biol ; 122(6): 400-409, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29801783

RESUMO

Microorganisms are essential to the functionality of the soil, particularly in organic matter decomposition and nutrient cycling, which regulate plant productivity and shape the soil structure. However, biotic and abiotic stresses greatly disrupt soil fungal communities and, thereby, disturb the ecosystem. This study quantified seasonal tolerances to UV-B radiation and heat of fungal communities, which could be cultured, found in soil from two native Atlantic forest fragments called F1 and F2, five reforested areas (RA) planted in 1994, 1997, 2004, 2007, and 2009 with native species of the Atlantic forest, and one sand mining degraded soil (SMDS). The cold activity of the soil fungal communities (FC) from the eight different areas was also studied. Higher tolerance to UV-B radiation and heat was found in the FC from the SMDS and the 2009RA, where the incidence of heat and UV radiation from sun was more intense, which caused selection for fungal taxa that were more UV-B and heat tolerant in those areas. Conversely, the FC from the native forests and older reforested sites were very susceptible to heat and UV-B radiation. The cold activity of the soil FC from different areas of the study showed an erratic pattern of responses among the sampling sites. Little difference in tolerance to UV-B radiation and heat was found among the FC of soil samples collected in different seasons; in general soil FC collected in winter were less tolerant to UV-B radiation, but not for heat. In conclusion, FC from SMDS soil that receive intense heat and UV radiation, as well as with low nutrient availability, were more tolerant to both UV-B radiation and heat.


Assuntos
Recuperação e Remediação Ambiental , Florestas , Resposta ao Choque Térmico , Micobioma/fisiologia , Micobioma/efeitos da radiação , Tolerância a Radiação , Microbiologia do Solo , Temperatura Alta , Mineração , Estações do Ano , Raios Ultravioleta
10.
Fungal Biol ; 122(6): 592-601, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29801804

RESUMO

The low survival of insect-pathogenic fungi when used for insect control in agriculture is mainly due to the deleterious effects of ultraviolet radiation and heat from solar irradiation. In this study, conidia of 15 species of entomopathogenic fungi were exposed to simulated full-spectrum solar radiation emitted by a Xenon Test Chamber Q-SUN XE-3-HC 340S (Q-LAB® Corporation, Westlake, OH, USA), which very closely simulates full-spectrum solar radiation. A dendrogram obtained from cluster analyses, based on lethal time 50 % and 90 % calculated by Probit analyses, separated the fungi into three clusters: cluster 3 contains species with highest tolerance to simulated full-spectrum solar radiation, included Metarhizium acridum, Cladosporium herbarum, and Trichothecium roseum with LT50 > 200 min irradiation. Cluster 2 contains eight species with moderate UV tolerance: Aschersonia aleyrodis, Isaria fumosorosea, Mariannaea pruinosa, Metarhizium anisopliae, Metarhizium brunneum, Metarhizium robertsii, Simplicillium lanosoniveum, and Torrubiella homopterorum with LT50 between 120 and 150 min irradiation. The four species in cluster 1 had the lowest UV tolerance: Lecanicillium aphanocladii, Beauveria bassiana, Tolypocladium cylindrosporum, and Tolypocladium inflatum with LT50 < 120 min irradiation. The QSUN Xenon Test Chamber XE3 is often used by the pharmaceutical and automotive industry to test light stability and weathering, respectively, but it was never used to evaluate fungal tolerance to full-spectrum solar radiation before. We conclude that the equipment provided an excellent tool for testing realistic tolerances of fungi to full-spectrum solar radiation of microbial agents for insect biological control in agriculture.


Assuntos
Entomophthorales/efeitos dos fármacos , Entomophthorales/crescimento & desenvolvimento , Tolerância a Radiação , Energia Solar , Luz Solar , Raios Ultravioleta , Xenônio
11.
Fungal Biol ; 122(6): 621-628, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29801807

RESUMO

Survival of entomopathogenic fungi under solar ultraviolet (UV) radiation is paramount to the success of biological control of insect pests and disease vectors. The mutagenic compound 4-nitroquinoline 1-oxide (4-NQO) is often used to mimic the biological effects of UV radiation on organisms. Therefore, we asked whether tolerance to 4-NQO could predict tolerance to UV radiation in thirty isolates of entomopathogenic fungi and one isolate of a xerophilic fungus. A dendrogram obtained from cluster analyses based on the 50 and 90 % inhibitory concentrations (IC50 and IC90, respectively) divided the fungal isolates into six clusters numbered consecutively based on their tolerance to 4-NQO. Cluster 6 contained species with highest tolerance to 4-NQO (IC50 > 4.7 µM), including Mariannaea pruinosa, Lecanicillium aphanocladii, and Torrubiella homopterorum. Cluster 1 contained species least tolerant to 4-NQO (IC50 < 0.2 µM), such as Metarhizium acridum (ARSEF 324), Tolypocladium geodes, and Metarhizium brunneum (ARSEF 7711). With few exceptions, the majority of Metarhizium species showed moderate to low tolerances (IC50 between 0.4 and 0.9 µM) and were placed in cluster 2. Cluster 3 included species with moderate tolerance (IC50 between 1.0 and 1.2 µM). In cluster 4 were species with moderate to high tolerance (IC50 between 1.3 and 1.6 µM). Cluster 5 contained the species with high tolerance (IC50 between 1.9 and 4.0 µM). The most UV tolerant isolate of M. acridum, ARSEF 324, was the least tolerant to 4-NQO. Also, L. aphanocladii, which is very susceptible to UV radiation, showed high tolerance to 4-NQO. Our results indicate that tolerance to 4-NQO does not correlate with tolerance to UV radiation. Therefore this chemical compound is not a predictor of UV tolerance in entomopathogenic fungi.


Assuntos
4-Nitroquinolina-1-Óxido/farmacologia , Entomophthorales/efeitos dos fármacos , Metarhizium/efeitos dos fármacos , Mutagênicos/farmacologia , Tolerância a Radiação , Estresse Fisiológico , Animais , Entomophthorales/crescimento & desenvolvimento , Entomophthorales/efeitos da radiação , Insetos/microbiologia , Metarhizium/crescimento & desenvolvimento , Metarhizium/efeitos da radiação , Controle Biológico de Vetores , Raios Ultravioleta
12.
Front Microbiol ; 9: 402, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29568288

RESUMO

Since 1999 Vaccinia virus (VACV) outbreaks involving bovines and humans have been reported in Brazil; this zoonosis is known as Bovine Vaccinia (BV) and is mainly an occupational disease of milkers. It was only in 2008 (and then again in 2011 and 2014) however, that VACV was found causing natural infections in Brazilian equids. These reports involved only equids, no infected humans or bovines were identified, and the sources of infections remain unknown up to date. The peculiarities of Equine Vaccinia outbreaks (e.g., absence of human infection), the frequently shared environments, and fomites by equids and bovines in Brazilian farms and the remaining gaps in BV epidemiology incited a question over OPV serological status of equids in Brazil. For this report, sera from 621 equids - representing different species, ages, sexes and locations of origin within Minas Gerais State, southeast Brazil - were examined for the presence of anti-Orthopoxvirus (OPV) antibodies. Only 74 of these were sampled during an Equine Vaccinia outbreak, meaning some of these specific animals presented typical lesions of OPV infections. The majority of sera, however, were sampled from animals without typical signs of OPV infection and during the absence of reported Bovine or Equine Vaccinia outbreaks. Results suggest the circulation of VACV among equids of southeast Brazil even prior to the time of the first VACV outbreak in 2008. There is a correlation of OPVs outbreaks among bovines and equids although many gaps remain to our understanding of its nature. The data obtained may even be carefully associated to recent discussion over OPVs history. Moreover, data is available to improve the knowledge and instigate new researches regarding OPVs circulation in Brazil and worldwide.

13.
Arch Virol ; 162(10): 2971-2981, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28620810

RESUMO

Usurpation of the host's signalling pathways is a common strategy employed by viruses to promote their successful replication. Here we show that infection with the orthopoxvirus vaccinia virus (VACV) leads to sustained stimulation of c-Jun activity during the entire infective cycle. This stimulation is temporally regulated through MEK/ERK or MKK/JNK pathways, i.e. during the early/mid phase (1 to 6 hpi) and in the late phase (9 to 24 hpi) of the infective cycle, respectively. As a transcriptional regulator, upon infection with VACV, c-Jun is translocated from the cytoplasm to the nucleus, where it binds to the AP-1 DNA sequence found at the promoter region of its target genes. To investigate the role played by c-Jun during VACV replication cycle, we generated cell lines that stably express a c-Jun-dominant negative (DNc-Jun) mutation. Our data revealed that c-Jun is required during early infection to assist with viral DNA replication, as demonstrated by the decreased amount of viral DNA found in the DNc-Jun cells. We also demonstrated that c-Jun regulates the expression of the early growth response gene (egr-1), a gene previously shown to affect VACV replication mediated by MEK/ERK signalling. VACV-induced stimulation of the MKK/JNK/JUN pathway impacts viral dissemination, as we observed a significant reduction in both viral yield, during late stages of infection, and virus plaque size. Collectively, our data suggest that, by modulating the host's signalling pathways through a common target such as c-Jun, VACV temporally regulates its infective cycle in order to successfully replicate and subsequently spread.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , MAP Quinase Quinase 4/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Vaccinia virus/fisiologia , Animais , Linhagem Celular , DNA Viral , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/genética , Fibroblastos/virologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação Viral da Expressão Gênica/fisiologia , MAP Quinase Quinase 4/genética , MAP Quinase Quinase Quinases/genética , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Fosforilação , Proteínas Proto-Oncogênicas c-jun/genética , Replicação Viral
14.
Genet Mol Biol ; 40(1 suppl 1): 276-291, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28304073

RESUMO

The multiplication of cells in all living organisms requires a tight regulation of DNA replication. Several mechanisms take place to ensure that the DNA is replicated faithfully and just once per cell cycle in order to originate through mitoses two new daughter cells that contain exactly the same information from the previous one. A key control mechanism that occurs before cells enter S phase is the formation of a pre-replication complex (pre-RC) that is assembled at replication origins by the sequential association of the origin recognition complex, followed by Cdt1, Cdc6 and finally MCMs, licensing DNA to start replication. The identification of pre-RC members in all animal and plant species shows that this complex is conserved in eukaryotes and, more importantly, the differences between kingdoms might reflect their divergence in strategies on cell cycle regulation, as it must be integrated and adapted to the niche, ecosystem, and the organism peculiarities. Here, we provide an overview of the knowledge generated so far on the formation and the developmental controls of the pre-RC mechanism in plants, analyzing some particular aspects in comparison to other eukaryotes.

15.
Noncoding RNA ; 3(4)2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29657296

RESUMO

Studies have highlighted the importance of non-coding RNA regulation in plant-microbe interaction. However, the roles of sugarcane microRNAs (miRNAs) in the regulation of disease responses have not been investigated. Firstly, we screened the sRNA transcriptome of sugarcane infected with Acidovorax avenae. Conserved and novel miRNAs were identified. Additionally, small interfering RNAs (siRNAs) were aligned to differentially expressed sequences from the sugarcane transcriptome. Interestingly, many siRNAs aligned to a transcript encoding a copper-transporter gene whose expression was induced in the presence of A. avenae, while the siRNAs were repressed in the presence of A. avenae. Moreover, a long intergenic non-coding RNA was identified as a potential target or decoy of miR408. To extend the bioinformatics analysis, we carried out independent inoculations and the expression patterns of six miRNAs were validated by quantitative reverse transcription-PCR (qRT-PCR). Among these miRNAs, miR408-a copper-microRNA-was downregulated. The cleavage of a putative miR408 target, a laccase, was confirmed by a modified 5'RACE (rapid amplification of cDNA ends) assay. MiR408 was also downregulated in samples infected with other pathogens, but it was upregulated in the presence of a beneficial diazotrophic bacteria. Our results suggest that regulation by miR408 is important in sugarcane sensing whether microorganisms are either pathogenic or beneficial, triggering specific miRNA-mediated regulatory mechanisms accordingly.

16.
Genet. mol. biol ; 40(1,supl.1): 276-291, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-892392

RESUMO

Abstract The multiplication of cells in all living organisms requires a tight regulation of DNA replication. Several mechanisms take place to ensure that the DNA is replicated faithfully and just once per cell cycle in order to originate through mitoses two new daughter cells that contain exactly the same information from the previous one. A key control mechanism that occurs before cells enter S phase is the formation of a pre-replication complex (pre-RC) that is assembled at replication origins by the sequential association of the origin recognition complex, followed by Cdt1, Cdc6 and finally MCMs, licensing DNA to start replication. The identification of pre-RC members in all animal and plant species shows that this complex is conserved in eukaryotes and, more importantly, the differences between kingdoms might reflect their divergence in strategies on cell cycle regulation, as it must be integrated and adapted to the niche, ecosystem, and the organism peculiarities. Here, we provide an overview of the knowledge generated so far on the formation and the developmental controls of the pre-RC mechanism in plants, analyzing some particular aspects in comparison to other eukaryotes.

17.
PLoS One ; 11(12): e0166473, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27936012

RESUMO

Sugarcane is an important tropical crop mainly cultivated to produce ethanol and sugar. Crop productivity is negatively affected by Acidovorax avenae subsp avenae (Aaa), which causes the red stripe disease. Little is known about the molecular mechanisms triggered in response to the infection. We have investigated the molecular mechanism activated in sugarcane using a RNA-seq approach. We have produced a de novo transcriptome assembly (TR7) from sugarcane RNA-seq libraries submitted to drought and infection with Aaa. Together, these libraries present 247 million of raw reads and resulted in 168,767 reference transcripts. Mapping in TR7 of reads obtained from infected libraries, revealed 798 differentially expressed transcripts, of which 723 were annotated, corresponding to 467 genes. GO and KEGG enrichment analysis showed that several metabolic pathways, such as code for proteins response to stress, metabolism of carbohydrates, processes of transcription and translation of proteins, amino acid metabolism and biosynthesis of secondary metabolites were significantly regulated in sugarcane. Differential analysis revealed that genes in the biosynthetic pathways of ET and JA PRRs, oxidative burst genes, NBS-LRR genes, cell wall fortification genes, SAR induced genes and pathogenesis-related genes (PR) were upregulated. In addition, 20 genes were validated by RT-qPCR. Together, these data contribute to a better understanding of the molecular mechanisms triggered by the Aaa in sugarcane and opens the opportunity for the development of molecular markers associated with disease tolerance in breeding programs.


Assuntos
Comamonadaceae/crescimento & desenvolvimento , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Saccharum/genética , Transcriptoma/genética , Comamonadaceae/fisiologia , Ontologia Genética , Interações Hospedeiro-Patógeno , Anotação de Sequência Molecular , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharum/microbiologia , Análise de Sequência de RNA/métodos
18.
Biosci. j. (Online) ; 32(4): 999-1007, july/aug. 2016. tab
Artigo em Inglês | LILACS | ID: biblio-965630

RESUMO

The increasing tomato demand for the food market motivates improvements and the use of new biotechnologies in this fruit's production. The hybrid crop stands out for fruit production resistant to rot and postharvest wilt (long-life crops). Within this context, consumption of genetically modified food deserves attention regarding the safety and nutritional aspects due to the fact that inclusion and/or overexpression of genetic traits can cause harm to human health in the short or long term. In this scenario, this study aimed to evaluate genotoxicity and mutagenicity from different varieties of long-life tomatoes obtained by genetic breeding and also determines main bioactive compounds and antioxidant activity. The genotoxicity and mutagenicity were analyzed via the micronucleus test and the evaluation of chromosome aberrations in mice bone marrow respectively. We have also analyzed carotene, beta-carotene, lycopene, total phenol and flavonoid contents via spectrophotometry and antioxidant activity via DPPH radical scavenging assay. Considering the results obtained, it is possible to conclude that despite the absence of significant genotoxic activity among the evaluated samples, the antioxidant activity and the differences found in composition seems to be ruled by genetic factors, possibly due to the genetic breeding.


O aumento da demanda na produção de tomate para o mercado alimentício vem incentivando transformações e implementações de novas biotecnologias na produção desse fruto, destacando-se a utilização cultivares híbridas que produzem frutos com maior resistência ao fenecimento e apodrecimento após colheita (cultivares do tipo longa vida). Dentro deste contexto, sabe-se que o consumo de alimentos oriundos de melhoramento genético necessita de atenção no aspecto de segurança alimentar e poder nutricional, pois a inclusão e/ou super expressão de características genéticas de interesse pode acarretar a curto ou em longo prazo danos à saúde humana. Neste cenário, o presente estudo teve como objetivo avaliar a genotoxicidade e mutagenicidade de diferentes variedades de tomates do tipo "longa vida" obtidos por melhoramento genético, assim como determinar seus principais compostos bioativos e atividade antioxidante. A genotoxicidade e mutagenicidade foram analisados por meio do teste do micronúcleo e pela avaliação de aberrações cromossômicas em medula óssea de camundongos. Foram determinados caroteno, betacaroteno, licopeno e o conteúdo de polifenóis e flavonoides totais por meio espectrofotométrico e atividade antioxidante pelo método do sequestro do radical DPPH. Diante dos resultados obtidos foi possível concluir que apesar da ausência de atividade genotóxica significativa entre as amostras avaliadas, as diferenças na composição e bioatividade antioxidante observadas no presente estudo, parecem ser governados por fatores genéticos, possivelmente provenientes do melhoramento genético realizado.


Assuntos
Biotecnologia , Aberrações Cromossômicas , Solanum lycopersicum , Genotoxicidade , Melhoramento Vegetal , Testes de Mutagenicidade
19.
Am J Trop Med Hyg ; 94(5): 1080-4, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-26976882

RESUMO

Dengue is currently regarded as a major public health problem worldwide. In a hyperendemic region during an outbreak, we detected the co-circulation of all Dengue virus (DENV) serotypes including two different genotypes of DENV-3 and DENV-4, and concurrent infections with up to three serotypes were identified in symptomatic patients. A total of 49 acute phase plasma samples from patients clinically suspected of dengue were collected during the 4 weeks of May 2013. DENV-1-4 was detected by reverse transcriptase semi-nested polymerase chain reaction in 33 samples (67.3%), of which 26 DNA fragments were sequenced. Twenty samples (76.9%) were identified with a single DENV serotype and six (23.1%) with more than one serotype. DENV-3 was the predominant serotype of the outbreak. On the basis of phylogenetic analyses, DENV-1 isolates belong to genotype V, DENV-2 to American-Asian genotype, DENV-3 to genotypes I and III, and DENV-4 to genotypes I and II.


Assuntos
Coinfecção , Vírus da Dengue/classificação , Dengue/epidemiologia , Dengue/virologia , Brasil/epidemiologia , Vírus da Dengue/genética , Doenças Endêmicas , Humanos , Fatores de Tempo
20.
Am J Trop Med Hyg ; 94(3): 494-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26787153

RESUMO

Orthobunyaviruses are arboviruses in which at least 30 members are human pathogens. The members of group C orthobunyaviruses were first isolated in the Brazilian Amazon in 1950, since that time little information is accumulated about ecology and the medical impact of these virus groups in Brazil. Herein, we describe the evidence of Apeu virus (APEUV; an Orthobunyavirus member) infection in wild monkeys from the Brazilian Amazon forest. APEUV was detected by using a neutralizing antibody in serum and its RNA, suggesting past and acute infection of Amazonian monkeys by this virus. These results altogether represent an important contribution of orthobunyavirus ecology in the Amazon and an update about recent circulation and risk for humans with expansion of the cities to Amazon forest.


Assuntos
Alouatta , Animais Selvagens , Infecções por Bunyaviridae/veterinária , Cebus , Doenças dos Macacos/virologia , Orthobunyavirus/isolamento & purificação , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Infecções por Bunyaviridae/epidemiologia , Infecções por Bunyaviridae/virologia , Doenças dos Macacos/epidemiologia , RNA Viral/sangue
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