Project description:Transcription profiling of the DSF regulon in Xanthomonas oryzae pv. oryzae (Xoo) using wild type and the rpfF mutant. Cell-cell signaling mediated by the quorum sensing molecule known as Diffusible Signaling factor (DSF) is required for virulence of Xanthomonas group of plant pathogens. DSF in different Xanthomonas and the closely related plant pathogen Xylella fastidiosa regulates diverse traits in a strain specific manner. The transcriptional profiling performed in this study is to elucidate the traits regulated by DSF from the Indian isolate of Xanthomonas oryzae pv. oryzae, which exhibits traits very different from other Xanthomonas group of plant pathogen. In this study, transcription analysis was done between a wild type Xanthomonas oryzae pv. oryzae strain and an isogenic strain that has a mutation in the DSF biosynthetic gene rpfF.
Project description:TITLE: Transcriptional profiling of Rgene-mediated responses in rice PROJECT DESCRIPTION: The dominant gene Xa7 and the recessive gene xa5 of rice confer resistance to several races of the bacterial blight pathogen Xanthomonas oryzae pv. oryzae (Xoo). To reveal the modes of action and the defense responses these genes initiate, we decided to obtain the global transcriptional profiles of the rice cultivars IRBB7, IRBB5 (which harbor Xa7 and xa5, respectively) and IR24 undergoing early infection by the Xoo Race 2 strain PXO86. Both IRBB7 and IRBB5 are resistant to PXO86 (which carry the corresponding avirulence genes avrXa7 and avrxa5), whereas IR24 is susceptible. We inoculated by vacuum infiltration the three rice cultivars ten days after seed germination (or 2 weeks after sowing) and collected inoculated tissue at 5 different timepoints within the first day after inoculation. The transcriptional profiles obtained will provide valuable insight into the similarities and differences between incompatible interactions mediated by a dominant and a recessive Rgene, in comparison to a compatible interaction. ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, David O Nino-Liu. The equivalent experiment is OS4 at PLEXdb.]
Project description:we emphatically monitored the responsive changes of rice miRNAs at 0, 8, 24 hours across Xoo strain PXO86 infection in its compatible rice variety IR24 and incompatible variety IRBB5 by small RNA sequencing, and the genes targeted by miRNAs were also detected via degradome technology. These findings provide new insights into the complex roles of characteristic miRNAs and their targets in rice-Xoo interactions.
Project description:Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas oryzae pv. oryzicola (Xoc) lead to the devastating rice bacterial diseases and have a very close genetic relationship. There are tissue-specificity differences between Xoo and Xoc, i.e., Xoo only proliferating in xylem vessels and Xoc spreading in intercellular space of mesophyll cell. But there is little known about the determinants of tissue-specificity between Xoo and Xoc. Here we show that Xoc can spread in the intercellular spaces of mesophyll cells to form streak lesions. But Xoo is restricted to growth in the intercellular spaces of mesophyll cells on the inoculation sites. In vivo, Xoc largely breaks the surface and inner structures of cell wall in mesophyll cells in comparison with Xoo. In vitro, Xoc strongly damages the cellulose filter paper in comparison with Xoo. These results suggest that the stronger cell wall-degradation ability of Xoc than that of Xoo may be directly determining the tissue-specificity.
Project description:Xanthomonas campestris pv. raphani and X. campestris pv. campestris are the causal agents of bacterial spot and black rot of crucifers (Brassicaceae), respectively. Both pathogens are threats in the cultivation of cruciferous crops such as cabbage. Here, we sequenced a strain of each of these pathogens.
Project description:Xanthomonas oryzae pv. oryzae strain PXO99A, so called Xoo, is disable to infect in rice cultivar carrying Xa21 gene. Disrupted mutant of raxR gene, response regulator of two-component regulatory system (TCS), in Xoo was previously shown to partially retrieve back the bacterial capability to establish in Xa21 rice. RaxR was shown to mediate the expression of other rax gene operon members and also its expression is changed dependent on cell population density. In this study, we investigated the regulatory mechanisms mediated by RaxR using whole-genome transcriptional profiling analysis in comparison of (i) PXO99R (PXO99 strain lacking RaxR) vs. PXO99, (ii) PXO99Rox (PXO99 strain overexpressing RaxR) vs. PXO99, and (iii) PXO99Rox vs. PXO99R. As a result of array analysis, we revealed that RaxR is not only required for AvrXa21 activitiy, it also plays roles in regulatory functions, for example, pathogenicity, motility, and stress tolerance. Then, we generated knock out mutants of RaxR regulon members to validate regulatory functions of RaxR and to extend other biological impacts of RaxR beyond the Xoo AvrXa21 activity. The combined interpretation from array analysis and mutant functional validation presents the complexity of regulatory pathways between AvrXa21 activity and other biological activities in Xoo. Keywords: Comparative transcription profiling between modified genetic mutant and wild type
Project description:This SuperSeries is composed of the following subset Series: GSE9640: Transcriptome Profiling of Xanthomonas oryzae pv. oryzae and Xanthomonas oryzae pv. oryzicola on two different medias GSE9643: Transcriptome Profiling of Xanthomonas oryzae pv. oryzae knockout mutants at different hybridization conditions and PMTs Keywords: SuperSeries Refer to individual Series
Project description:Xanthomonas oryzae pv. oryzae (Xoo) and X. oryzae pv. oryzicola (Xoc) are important bacterial pathogens of the worldwide staple and grass model, rice. Xoo invades rice vascular tissue to cause bacterial leaf blight, a serious disease of rice throughout the world. Xoc colonizes the parenchyma tissue to cause bacterial leaf steak, a disease of emerging importance. We have designed oligonucleotide probes (50-70-mers) represented 2,858 Xoo genes and 1,816 Xoc genes annotated by The Institute for Genomic Research (TIGR). To validate the Xo arrays, self-hybridization samples and tests of the non-specific hybridization using randomly spotted oligonucleotides corresponding to the hygromycin phosphotransferase gene (hph), and blank spot and of the correlation coefficient between biological replicates as well as between duplicate spots revealed that the data generated from our oligo array were highly reliable and consistent. To demonstrate application of Xo array, we performed expression profiling experiments on arrays hybridized with RNA of Xoo and Xoc grown in the two different nutrient-condition media. Several sets of genes involved in bacterial movement, chemotaxis, and hrp genes differentially express in response to different treatment. Due to comprehensive views of microarray study, extended biological events of plant-bacteria interaction was described. This publicly available microarray for Xanthomonas oryzae (Xo) is an enabling resource for a large and international community of scientists to better understand not only Xo biology but also many other Xanthomonas species that cause significant losses on crops. Keywords: Media condition response