Consulta: creatorFacets:"Freitas-Astúa,Juliana"
Registros recuperados: 14
Data/hora: 13/06/2024 02:10:21

Genetic machinery for RNA silencing and defense against viruses in Citrus
Provedor de dados: 74
Autores: Benedito,Vagner Augusto; Faria,Laura; Freitas-Astúa,Juliana; Figueira,Antonio.
RNA silencing mechanisms are conserved throughout eukaryotic evolution, possibly due to their importance in viral resistance and other aspects of cell biology. Here, we explored the Citrus EST (CitEST) database in search of sequences related to the most important known genes involved in RNA silencing. Transcripts strongly matching Argonaute (AGO), Dicer-like (DCL), Hua enhancer (HEN), and RNA-dependent RNA Polymerase (RdRP) were found in many of the citrus libraries. The reads were clustered and quantified. This shows that post-transcriptional gene silencing apparatus is active in citrus. It seems plausible that a better understanding of the players of RNA silencing in Citrus spp. and related genera may help create new tools to defeat the viral diseases...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: CitEST; Gene silencing; PTGS.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500027

CitEST libraries
Provedor de dados: 74
Autores: Targon,Maria Luísa P. Natividade; Takita,Marco Aurélio; Amaral,Alexandre M. do; Souza,Alessandra A. de; Locali-Fabris,Eliane Cristina; Dorta,Sílvia de Oliveira; Borges,Kleber Martins; Souza,Juliana Mendonça de; Rodrigues,Carolina Munari; Lucheta,Adriano Reis; Freitas-Astúa,Juliana; Machado,Marcos Antonio.
In order to obtain a better understanding of what is citrus, 33 cDNA libraries were constructed from different citrus species and genera. Total RNA was extracted from fruits, leaves, flowers, bark, seeds and roots, and subjected or not to different biotic and abiotic stresses (pathogens and drought) and at several developmental stages. To identify putative promoter sequences, as well as molecular markers that could be useful for breeding programs, one shotgun library was prepared from sweet orange (Citrus sinensis var. Olimpia). In addition, EST libraries were also constructed for a citrus pathogen, the oomycete Phythophthora parasitica in either virulent or avirulent form. A total of 286,559 cDNA clones from citrus were sequenced from their 5’ end,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: ESTs; Shotgun; Citrus; Phytopathogen.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500030

An in silico analysis of the key genes involved in flavonoid biosynthesis in Citrus sinensis
Provedor de dados: 74
Autores: Lucheta,Adriano R.; Silva-Pinhati,Ana Carla O.; Basílio-Palmieri,Ana Carolina; Berger,Irving J.; Freitas-Astúa,Juliana; Cristofani,Mariângela.
Citrus species are known by their high content of phenolic compounds, including a wide range of flavonoids. In plants, these compounds are involved in protection against biotic and abiotic stresses, cell structure, UV protection, attraction of pollinators and seed dispersal. In humans, flavonoid consumption has been related to increasing overall health and fighting some important diseases. The goals of this study were to identify expressed sequence tags (EST) in Citrus sinensis (L.) Osbeck corresponding to genes involved in general phenylpropanoid biosynthesis and the key genes involved in the main flavonoids pathways (flavanones, flavones, flavonols, leucoanthocyanidins, anthocyanins and isoflavonoids). A thorough analysis of all related putative genes...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Phenylpropanoids; Sweet orange; Expressed sequence tags (EST); Secondary metabolism.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500010

Analysis of expressed sequence tags from Citrus sinensis L. Osbeck infected with Xylella fastidiosa
Provedor de dados: 74
Autores: Souza,Alessandra A. de; Takita,Marco A.; Coletta-Filho,Helvécio D.; Targon,Maria Luisa P.N.; Carlos,Eduardo F.; Locali-Fabris,Eliane C.; Amaral,Alexandre M.; Freitas-Astúa,Juliana; Silva-Pinhati,Ana Carla O.; Boscariol-Camargo,Raquel L.; Berger,Irving J.; Rodrigues,Carolina M.; Reis,Marcelo S.; Machado,Marcos A.
In order to understand the genetic responses resulting from physiological changes that occur in plants displaying citrus variegated chlorosis (CVC) symptoms, we adopted a strategy of comparing two EST libraries from sweet orange [Citrus sinensis (L.) Osbeck]. One of them was prepared with plants showing typical CVC symptoms caused by Xylella fastidiosa and the other with non-inoculated plants. We obtained 15,944 ESTs by sequencing the two cDNA libraries. Using an in silico hybridization strategy, 37 genes were found to have significant variation at the transcriptional level. Within this subset, 21 were up-regulated and 16 were down-regulated in plants with CVC. The main functional categories of the down-regulated transcripts in plants with CVC were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sweet orange; EST; CVC; Compatible interaction.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500023

Differentially expressed stress-related genes in the compatible citrus-Citrus leprosis virus interaction
Provedor de dados: 74
Autores: Freitas-Astúa,Juliana; Bastianel,Marinês; Locali-Fabris,Eliane C.; Novelli,Valdenice M.; Silva-Pinhati,Ana Carla; Basílio-Palmieri,Ana Carolina; Targon,Maria Luisa P.N.; Machado,Marcos A.
Leprosis, caused by Citrus leprosis virus, cytoplasmic type (CiLV-C), is the main viral disease in the Brazilian citrus industry. This occurs because of the widespread source of inoculum and the year-round presence of the vector, the tenuipalpid mite Brevipalpus phoenicis, in citrus plants. In addition, while some Citrus species are resistant to CiLV-C, C. sinensis, the main cultivated species in the country, is extremely susceptible to the disease. The main objective of this work was to identify genes in C. sinensis cv. Pêra plants that were differentially expressed after the host was challenged with CiLV-C. In order to accomplish that, cDNA libraries were constructed from healthy and CiLV-inoculated sweet orange leaves. Two hundred and fifty-four genes...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: EST; Disease; CiLV; In silico hybridization; Sweet orange; Citrus sinensis.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500026

In silico analysis of ESTs from roots of Rangpur lime (Citrus limonia Osbeck) under water stress
Provedor de dados: 74
Autores: Boscariol-Camargo,Raquel L.; Berger,Irving J.; Souza,Alessandra A.; Amaral,Alexandre M. do; Carlos,Eduardo F.; Freitas-Astúa,Juliana; Takita,Marco A.; Targon,Maria Luisa P.N.; Medina,Camilo L.; Reis,Marcelo S.; Machado,Marcos A.
CitEST project resulted in the construction of cDNA libraries from different Citrus sp. tissues under various physiological conditions. Among them, plantlets of Rangpur lime were exposed to hydroponic conditions with and without water stress using PEG6000. RNA from roots was obtained and generated a total of 4,130 valid cDNA reads, with 2,020 from the non-stressed condition and 2,110 from the stressed set. Bioinformatic analyses measured the frequency of each read in the libraries and yielded an in silico transcriptional profile for each condition. A total of 40 contigs were differentially expressed and allowed to detect up-regulated homologue sequences to well known genes involved in stress response, such as aquaporins, dehydrin, sucrose synthase, and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Expressed sequence tags; Transcription; Rootstock; Drought; Molecular response.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500019

In silico prediction of gene expression patterns in Citrus flavedo
Provedor de dados: 74
Autores: Berger,Irving J.; Freitas-Astúa,Juliana; Reis,Marcelo S.; Targon,Maria Luísa P.N.; Machado,Marcos A.
Out of the 18,942 flavedo expressed sequences (clusters plus singletons) in Citrus sinensis from the Citrus EST Project (CitEST), 25 were statistically supported to be differentially expressed in this tissue after a double in silico hybridization strategy against leaf-, flower-, and bark-derived ESTs. Five of them, two terpene synthases and three O-methyltransferases, are absent in the other citrus tissues with concomitant 2x2 statistics, supporting the hypothesis that they are putative flavedo-specific expressed sequences. The pattern of these differentially expressed sequences during fruit development suggests that most of them are developmentally regulated. Some expressed gene products, including a putative germin-like protein highly expressed in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: EST; Fruit; Gene expression; Orange; Tissue-specific.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500004

Genes associated with hypersensitive response (HR) in the citrus EST database (CitEST)
Provedor de dados: 74
Autores: Guidetti-Gonzalez,Simone; Freitas-Astúa,Juliana; Amaral,Alexandre Morais do; Martins,Natália F.; Mehta,Angela; Silva,Marilia Santos; Carrer,Helaine.
Plants are continuously exposed to pathogen attack, but successful infection is rare because they protect themselves against pathogens using a wide range of response mechanisms. One of them is the hypersensitive response (HR), which is a form of cell death often associated with plant resistance to pathogen infection to prevent the spreadsebpg@cnpq.br sebpg@cnpq.br of the potential pathogen from infected to uninfected tissues. Cell death is activated by recognition of pathogen-derived molecules by the resistance (R) gene products, and is associated with the massive accumulation of reactive oxygen species (ROS), salicylic acid (SA), and other pro-death signals such as nitric oxide (NO). The analysis of the citrus EST (CitEST) database revealed the presence...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Otic and abiotic stress response; Plant-pathogen incompatible interaction; Programmed cell death; Plant disease resistance.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500022

Differential expression of genes identified from Poncirus trifoliata tissue inoculated with CTV through EST analysis and in silico hybridization
Provedor de dados: 74
Autores: Cristofani-Yaly,Mariângela; Berger,Irving J.; Targon,Maria Luisa P.N.; Takita,Marco A.; Dorta,Sílvia de O.; Freitas-Astúa,Juliana; Souza,Alessandra A. de; Boscariol-Camargo,Raquel L.; Reis,Marcelo S.; Machado,Marcos A.
Citrus is the most important fruit crop in Brazil and Citrus tristeza virus (CTV) is considered one of the most important pathogens of citrus. Most citrus species and varieties are susceptible to CTV infection. However, Poncirus trifoliata, a close relative of citrus, is resistant to the virus. In order to better understand the responses of citrus plants to the infection of CTV, we constructed expressed sequence tag (EST) libraries with tissues collected from Poncirus trifoliata plants, inoculated or not with Citrus tristeza virus at 90 days after inoculation, grafted on Rangpur lime rootstocks. We generated 17,867 sequence tags from Poncirus trifoliata inoculated (8,926 reads) and not (8,941 reads) with a severe CTV isolate. A total of 2,782 TCs...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Citrus; Disease resistance; Citrus tristeza virus; Biotic stress.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000500025

Resposta diferencial de espécies e de híbridos de citros à leprose
Provedor de dados: 86
Autores: Freitas-Astúa,Juliana; Fadel,André Luiz; Bastianel,Marinês; Novelli,Valdenice Moreira; Antonioli-Luizon,Renata; Machado,Marcos Antônio.
O objetivo deste trabalho foi buscar novas fontes de resistência à leprose-dos-citros, no Banco Ativo de Germoplasma do Centro APTA Citros Sylvio Moreira, Instituto Agronômico, em Cordeirópolis, SP. Foram utilizadas plantas obtidas por sementes de 26 acessos, infectadas com o vírus da leprose-dos-citros (Citrus leprosis virus - CiLV), por meio do seu vetor Brevipalpus phoenicis. O aparecimento de lesões, a partir de 21 dias após a inoculação, foi observado em 11 dos genótipos testados (42,3%). Quinze espécies, entre elas Citrus pennivesiculata e C. celebica, comportaram-se como altamente resistentes, enquanto outras, como C. keraji, foram mais suscetíveis que o padrão C. sinensis. Os dados mostraram grande variação de respostas de Citrus spp. à leprose,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brevipalpus phoenicis; Citrus spp.; CiLV; Melhoramento genético; Resistência genética.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2008000700004

Comportamento de híbridos de citros em relação à infecção natural pelo Citrus tristeza virus e à presença de sintomas de descamamento eruptivo
Provedor de dados: 94
Autores: Rodrigues,Almir Santos; Barbosa,Cristiane de Jesus; Soares Filho,Walter dos Santos; Freitas-Astúa,Juliana.
O Programa de Melhoramento Genético de Citros da Embrapa Mandioca e Fruticultura vem gerando híbridos para utilização como porta-enxertos, que necessitam ser avaliados em relação ao comportamento frente à infecção natural por isolados locais de Citrus tristeza virus (CTV) e à presença de sintomas de descamamento eruptivo (BahiaBarkScaling disease - BBS). Este trabalho apresenta resultados da avaliação do comportamento de 141 híbridos (sob a forma de pés-francos ou enxertados) estabelecidos na área experimental da Embrapa Mandioca e Fruticultura, no Recôncavo Sul da Bahia. Foram avaliadas a presença e a severidade de sintomas de caneluras e descamamento por meio de escala de notas. Para detectar a presença do CTV, foi utilizado o método sorológico de ELISA...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: CTV; Citrus spp.; Poncirus; Fortunella.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452014000300027

Arabidopsis thaliana as a model host for Brevipalpus mite-transmitted viruses
Provedor de dados: 63
Autores: Arena,Gabriella Dias; Ramos-González,Pedro Luis; Nunes,Maria Andréia; Jesus,Camila Chabi; Calegario,Renata Faier; Kitajima,Elliot Watanabe; Novelli,Valdenice Moreira; Freitas-Astúa,Juliana.
ABSTRACT: Brevipalpus-transmitted viruses (BTV) are a taxonomically diverse group of plant viruses which severely affect a number of major crops. Members of the group can be sub-classified into cytoplasmic (BTV-C) or nuclear type (BTV-N) according to the accumulation sites of virions in the infected plant cells. Both types of BTV produce only local infections near the point of inoculation by viruliferous mites. Features of BTV-plant interactions such as the failure of systemic spread in their natural hosts are poorly understood. In this study we evaluated Arabidopsis thaliana, a model plant commonly used for the study of plant-virus interactions, as an alternative host for BTV. Infection of Arabidopsis with the BTV-N Coffee ringspot virus and Clerodendrum...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Clerodendrum chlorotic spot virus; Cilevirus; Solanum violaefolium ringspot virus; Coffee ringspot virus; Dichorhavirus.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162017000100085

RT-PCR para a detecção simultânea dos vírus da leprose e da tristeza dos citros
Provedor de dados: 102
Autores: Freitas-Astúa,Juliana; Locali,Eliane C.; Antonioli-Luizon,Renata; Astúa-Monge,Gustavo; Targon,Maria Luisa P.N.; Rodrigues,Vandeclei; Kitajima,Elliot W.; Machado,Marcos A.
Tipo: Info:eu-repo/semantics/report
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582005000600019

Comparative morpho-anatomical studies of the lesions caused by citrus leprosis virus on sweet orange
Provedor de dados: 42
Autores: Marques,João P.R.; Kitajima,Elliot W.; Freitas-Astúa,Juliana; Appezzato-da-Glória,Beatriz.
The leprosis disease shows a viral etiology and the citrus leprosis virus is considered its etiologic agent. The disease may show two types of cytopatologic symptom caused by two virus: nuclear (CiLV-N) and cytoplasmic (CiLV-C) types. The aim of this study was to compare the morpho-anatomical differences in the lesions caused by leprosis virus-cytoplasmic and nuclear types in Citrus sinensis (L.) Osbeck 'Pêra'. Leaf and fruit lesions were collected in Piracicaba/São Paulo (cytoplasmic type) and Monte Alegre do Sul/São Paulo and Amparo/São Paulo (nuclear type). The lesions were photographed and then fixed in Karnovsky solution, dehydrated in a graded ethylic series, embedded in hydroxy-ethyl methacrylate resin (Leica Historesin), sectioned (5 μm thick),...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anatoy; Hyperplasy; Hypertrophy; Traumatic gum ducts.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652010000200025