Xylella fastidiosa
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ABSTRACT:
PROVIDER: PRJNA98207 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:This is the study of the Heat Shock response of phytopathogenic bacteria Xylella fastidiosa. This series keeps the 25 minutes 40oC stimulus response (Aug 2005). Keywords: stress response; heat shock response
2006-06-01 | GSE3044 | GEO
Project description:Global gene expression analysis of the heat shock response in the phytopathogen Xylella fastidiosa
| PRJNA95077 | ENA
Project description:Global gene expression analysis of the phytopathogen Xylella fastidiosa at high iron availability
| PRJNA97307 | ENA
Project description:Global gene expression analysis of the phytopathogen Xylella fastidiosa at low iron availability
| PRJNA97311 | ENA
Project description:Genome sequence analysis of the bacterium Xylella fastidiosa revealed the presence of two genes, named rpoE and rseA, predicted to encode an ECF sigma factor and an anti-sigma factor, respectively. In this work, an rpoE null mutant was constructed in the citrus strain J1a12 and shown to be sensitive to exposure to heat shock and ethanol. To identify the X. fastidiosa σE regulon, global gene expression profiles were obtained by DNA microarray analysis of bacterial cells under heat shock identifying 23 sigmaE-dependent genes. Keywords: stress response, heat shock, rpoE mutant strain
2006-11-17 | GSE4960 | GEO
Project description:The global transcriptional response of the phytopathogenic bacterium X. fastidiosa to a sudden increase in salinity and osmolarity of the medium was investigated using DNA microarrays. Time-course experiments were carried out by exposing bacterial cells to high salinity (250 mM NaCl) and high osmolarity (300 mM sucrose) conditions revealing 142 upregulated genes under both stresses, including pathogenicity related genes, genes encoding transcriptional regulators, as well as genes related to DNA metabolism and mobile genetic elements. In addition, 38 genes were downregulated under both conditions, most of them related to ribosomal and heat shock proteins. A total of 192 genes were upregulated exclusively in the presence of NaCl, including genes encoding transporters, genes involved in oxidative-stress response and genes related to cell structure. A smaller number of genes (44 genes) were induced only in the presence of sucrose, most of them encoding hypothetical and conserved hypothetical proteins. Interestingly, 57% of the genes differentially expressed under both stress conditions have no putative function assigned, emphasizing the importance of high-throughput experiments to start the characterization of these genes in X. fastidiosa. Keywords: stress response, osmotic and salt stress Direct comparison between osmotic or salt stress condition and control (29oC) condition. Some hybridizations are dye-swaped. There are at least 3 biological replicates (independent harvest) and 2 technical replicates of each array (L - left and R - right).
2014-05-25 | E-GEOD-7126 | biostudies-arrayexpress
Project description:Pierce's disease, caused by the bacterium Xylella fastidiosa, is one of the most devastating diseases of cultivated grapes. To test the long-standing hypothesis that Pierce's disease results from pathogen-induced drought stress, we used the Affymetrix Vitis GeneChip to compare the transcriptional response of Vitis vinifera to Xylella infection, water deficit, or a combination of the two stresses. The results reveal a massive redirection of gene transcription involving 822 genes with a minimum 2-fold change (p<0.05), including the upregulation of transcripts for phenylpropanoid and flavonoid biosynthesis, pathogenesis related (PR) proteins, absisic acid (ABA)/jasmonic acid (JA)-responsive transcripts, and down-regulation of transcripts related to photosynthesis, growth and nutrition. Although the transcriptional response of plants to Xylella infection was largely distinct from the response of healthy plants to water stress, we find that 138 of the pathogen-induced genes exhibited a significantly stronger transcriptional response when plants were simultaneously exposed to infection and drought stress, suggesting a strong interaction between disease and water deficit. This interaction between drought stress and disease was mirrored in planta at the physiological level for aspects of water relations and photosynthesis, and in terms of the severity of disease symptoms and the extent of pathogen colonization, providing a molecular correlation of the classical concept of the disease triangle where environment impacts disease severity. Mature leaves were sampled from 2-year old V. vinifera cv. Cabernet sauvignon clone 8 vines 4 and 8 weeks post-mock or inoculation with Xylella fastidiosa (Pierce's disease). Vines were grown in growth chambers under non-water limiting and water limiting conditions (moderate and severe water stress)
2013-02-12 | E-GEOD-44213 | biostudies-arrayexpress
Project description:Xylella fastidiosa is a phytopathogenic bacterium responsible for diseases in many economically important crops. Although different strains have been studied, little is known about X. fastidiosa stress responses. One of the best characterized stresses in bacteria is the heat shock response, which induces the expression of specific genes to prevent protein misfolding and aggregation, and to promote degradation of the irreversibly denatured polypeptides. To investigate X. fastidiosa genes involved in the heat shock response, we performed a whole genome microarray analysis in a time-course experiment. Globally, 261 genes were induced (9.7%) and 222 genes were repressed (8.3%). The expression profiles of the differentially expressed genes were grouped and their expression patterns were validated by quantitative RT-PCR experiments. As expected, genes that presented the higher induction rates encoded chaperones and proteases. We determined the transcription start site of six heat shock inducible genes and analyzed their promoter regions, which allowed us to propose a putative consensus for 32 promoters in Xylella and suggest additional genes as putative members of this regulon. Besides the induction of classical heat shock protein genes, we observed the up-regulation of virulence-associated genes such as vapD, hemagglutinins, hemolysin and xylan degrading enzymes, which may indicate the importance of heat stress to bacterial pathogenesis. In addition, we observed the repression of genes related to fimbriae, aerobic respiration, protein biosynthesis, and the induction of genes related to the extracytoplasmic stress response and some phage-related genes, revealing the complex network of genes that work together in response to heat shock. Keywords: stress response; heat shock response
2006-06-01 | GSE4161 | GEO
Project description:Xylella fastidiosa is the etiologic agent of a wide range of plant diseases including citrus variegated chlorosis (CVC), a major threat to the Brazilian citrus industry. Genome sequences of several strains of this phytopathogen are accessible, enabling large-scale functional studies. Transcript levels in different iron availabilities were assessed with DNA microarrays representing 2608 (91.6%) coding sequences (CDS) of X. fastidiosa CVC strain 9a5c. When treated with the iron chelator 2,2-dipyridyl, 193 CDS were considered as up-regulated and 216 as down-regulated. In the presence of 100uM of ferric pyrophosphate, 218 and 256 CDS were considered as up- and down-regulated, respectively. Differential expression for a subset of 44 CDS was further evaluated by reverse transcription - quantitative PCR that showed a Pearson correlation of 0.77 with array results. The CDS differentially expressed upon the iron concentration shift participate in diverse cellular functions. Many CDS involved with regulatory functions, pathogenicity and cell structure, were modulated in both conditions tested suggesting that major changes in cell architecture and metabolism occur when X. fastidiosa cells are exposed to extreme variations in iron concentration. Interestingly, the modulated CDS include those related to colicin V-like bacteriocin synthesis and secretion and to pili/fimbriae functions. We also investigated the contribution of the ferric uptake regulator Fur to the iron regulon of X. fastidiosa. The promoter regions of strain 9a5c genome were screened for putative Fur boxes and candidates were analyzed by electrophoretic mobility shift assays. Taken together, our data support the hypothesis that Fur is not solely responsible for the modulation of the iron regulon of X. fastidiosa and present novel evidence for iron regulation of pathogenicity determinants. Keywords: stress response; response to iron-depleted condition
2007-09-01 | GSE5888 | GEO
Project description:Xylella fastidiosa is the etiologic agent of a wide range of plant diseases including citrus variegated chlorosis (CVC), a major threat to the Brazilian citrus industry. Genome sequences of several strains of this phytopathogen are accessible, enabling large-scale functional studies. Transcript levels in different iron availabilities were assessed with DNA microarrays representing 2608 (91.6%) coding sequences (CDS) of X. fastidiosa CVC strain 9a5c. When treated with the iron chelator 2,2-dipyridyl, 193 CDS were considered as up-regulated and 216 as down-regulated. In the presence of 100uM of ferric pyrophosphate, 218 and 256 CDS were considered as up- and down-regulated, respectively. Differential expression for a subset of 44 CDS was further evaluated by reverse transcription - quantitative PCR that showed a Pearson correlation of 0.77 with array results. The CDS differentially expressed upon the iron concentration shift participate in diverse cellular functions. Many CDS involved with regulatory functions, pathogenicity and cell structure, were modulated in both conditions tested suggesting that major changes in cell architecture and metabolism occur when X. fastidiosa cells are exposed to extreme variations in iron concentration. Interestingly, the modulated CDS include those related to colicin V-like bacteriocin synthesis and secretion and to pili/fimbriae functions. We also investigated the contribution of the ferric uptake regulator Fur to the iron regulon of X. fastidiosa. The promoter regions of strain 9a5c genome were screened for putative Fur boxes and candidates were analyzed by electrophoretic mobility shift assays. Taken together, our data support the hypothesis that Fur is not solely responsible for the modulation of the iron regulon of X. fastidiosa and present novel evidence for iron regulation of pathogenicity determinants. Keywords: stress response; response to iron-replete condition
2007-09-01 | GSE5886 | GEO