Project description:Comparative microarray-based transcriptome analysis of A. thaliana mlo2 mlo6 mlo12 mutants and wild type plants upon Golovinomyces orontii inoculation revealed an increased and accelerated accumulation of many defense-related transcripts. Despite the biotrophic nature of the interaction, this included the non-canonical activation of a jasmonic acid/ethylene-dependent transcriptional program.
Project description:Salicylic acid (SA) is a critical molecule mediating plant innate immunity with an important role limiting the growth and reproduction of the virulent powdery mildew (PM) Golovinomyces orontii on Arabidopsis thaliana. To investigate this later phase of the PM interaction, and the role played by SA, we performed replicated global expression profiling for wild type and SA biosynthetic mutant ics1 Arabidopsis from 0 to 7 days post infection. We found that ICS1-impacted genes comprise 3.8% of profiled genes with known molecular markers of Arabidopsis defense ranked very highly by the multivariate empirical Bayes statistic (T2 statistic ((Tai and Speed, 2006)). Functional analyses of T2-selected genes identified statistically significant PM-impacted processes including photosynthesis, cell wall modification, and alkaloid metabolism that are ICS1-independent. ICS1-impacted processes include redox, vacuolar transport/secretion, and signaling. Our data also supports a role for ICS1 (SA) in iron and calcium homeostasis and identifies components of SA crosstalk with other phytohormones. Through our analysis, 39 novel PMâimpacted transcriptional regulators were identified. Insertion mutants in one of these regulators, PUX2, results in significantly reduced reproduction of the powdery mildew in a cell death independent manner. Though little is known about PUX2, PUX1 acts as a negative regulator of Arabidopsis CDC48 (Rancour et al., 2004; Park et al., 2007), an essential AAA-ATPase chaperone that mediates diverse cellular activities including homotypic fusion of ER and Golgi membranes, ER-associated protein degradation, cell cycle progression, and apoptosis. Future work will elucidate the functional role of the novel regulator PUX2 in PM resistance. Experiment Overall Design: Arabidopsis whole leaves were harvested at 6h, 1 day, 3 days, 5 days and 7 days after Golovinomyces orontii infection for RNA extraction and hybridization to Affymetrix Arabidopsis ATH1 microarrays. Gene expression profiles were obtained for wild type Columbia-0 and enhanced disease susceptibility mutant eds16-1, a null isochorismate synthase 1 (At1g74710) mutant. In parallel, uninfected samples were collected at 0 hr and 7days from wild type and mutant plants. The experiment includes 4 biological replicates.
Project description:Salicylic acid (SA) is a critical molecule mediating plant innate immunity with an important role limiting the growth and reproduction of the virulent powdery mildew (PM) Golovinomyces orontii on Arabidopsis thaliana. To investigate this later phase of the PM interaction, and the role played by SA, we performed replicated global expression profiling for wild type and SA biosynthetic mutant ics1 Arabidopsis from 0 to 7 days post infection. We found that ICS1-impacted genes comprise 3.8% of profiled genes with known molecular markers of Arabidopsis defense ranked very highly by the multivariate empirical Bayes statistic (T2 statistic ((Tai and Speed, 2006)). Functional analyses of T2-selected genes identified statistically significant PM-impacted processes including photosynthesis, cell wall modification, and alkaloid metabolism that are ICS1-independent. ICS1-impacted processes include redox, vacuolar transport/secretion, and signaling. Our data also supports a role for ICS1 (SA) in iron and calcium homeostasis and identifies components of SA crosstalk with other phytohormones. Through our analysis, 39 novel PM–impacted transcriptional regulators were identified. Insertion mutants in one of these regulators, PUX2, results in significantly reduced reproduction of the powdery mildew in a cell death independent manner. Though little is known about PUX2, PUX1 acts as a negative regulator of Arabidopsis CDC48 (Rancour et al., 2004; Park et al., 2007), an essential AAA-ATPase chaperone that mediates diverse cellular activities including homotypic fusion of ER and Golgi membranes, ER-associated protein degradation, cell cycle progression, and apoptosis. Future work will elucidate the functional role of the novel regulator PUX2 in PM resistance. Keywords: time course, pathogen response
Project description:LC-MS/MS data were collected from uninfected and parallel Golovinomyces orontii MGH1- infected Arabidopsis thaliana leaf tissue (leaves 7-9) at 12 days post inoculation to understand the manipulation of host lipid metabolism by the powdery mildew.
Project description:Here, we sought to describe qualitative and quantitative changes in the global gene expression profiles of susceptible Arabidopsis plants supporting the development of G. cichoracearum haustoria. We analyzed the features of compatibility at this infection stage, and further evaluated the contribution of the SA- and JA/ET-dependent defense signaling pathways in the pathogen-induced responses by comparing responses in infected wild-type, npr1-1, and jar1-1 plants. Our findings collectively contribute to knowledge regarding early host cell alterations generated in response to attack by this virulent obligate biotrophic fungus. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Disease State: plant infected/uninfected with Golovinomyces orontii Genotype: wt/mutant strains Keywords: Logical Set Computed
Project description:Here, we sought to describe qualitative and quantitative changes in the global gene expression profiles of susceptible Arabidopsis plants supporting the development of G. cichoracearum haustoria. We analyzed the features of compatibility at this infection stage, and further evaluated the contribution of the SA- and JA/ET-dependent defense signaling pathways in the pathogen-induced responses by comparing responses in infected wild-type, npr1-1, and jar1-1 plants. Our findings collectively contribute to knowledge regarding early host cell alterations generated in response to attack by this virulent obligate biotrophic fungus. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Disease State: plant infected/uninfected with Golovinomyces orontii Genotype: wt/mutant strains Keywords: Logical Set
Project description:We performed RNA-sequencing of Golovinomyces orontii-infected Arabidopsis leaves of wild type, the double or triple mutants of AtMLKLs to examine the role of AtMLKLs in response to the powdery mildew fungus.