Project description:Natural variation within plant species is an important resource for discovery of genes controlling biological traits. Gene-expression profiling of natural variation is increasingly used to identify genes affecting a trait. Here, we explored variation among Arabidopsis thaliana accessions with respect to defense against Pseudomonas syringae pv. tomato DC3000 (Pst), with a focus on R-gene mediated resistance triggered by the Pst type III effector protein AvrRpt2. We explored variation at two phenotypic levels: growth of the bacteria and hypersensitive response (HR) measured by electrolyte leakage. Considerable variation among accessions was found at both phenotypic levels. The genetic variation among accessions affected both growth of Pst with (Pst avrRpt2) and without (Pst) the AvrRpt2 effector, with some variation being specific for the bacterial strains, and other variation affecting both strains in a similar manner. Variation in HR was not correlated with variation in bacterial growth. Additionally we examine variation in gene-expression profiles after mock- and Pst avrRpt2-inoculated plants, obtained using a dedicated microarray Gene-expression profiling at 6 h post inoculation identified clusters of genes from which expression levels are correlated with bacterial growth and electrolyte leakage. The expression levels of some of these clusters correlate with more than one phenotypic characteristic, such as growth of both Pst and Pst avrRpt2, whereas other clusters were correlated with just one biological parameter. Thus we demonstrate that variation in gene-expression profiles among Arabidopsis accessions is correlated with variation in phenotypic responses. Keywords: Comparisons of Arabidopsis thaliana accessions with respect to inoculation with Pseudomonas syringae pv tomato avrRpt2.
2007-08-09 | GSE8298 | GEO
Project description:Transcriptomic characterization of maize hypersensitive response (HR)
Project description:Cellulase, a Type II secretion system secreted protein of Xanthomonas oryzae pv. oryzae (Xoo; the casual of bacterial leaf blight of rice) is a potent inducer of rice defense responses such as hypersensitive response like reactions (HR), callose depositions, cell death associated with nuclear fragmentations and impart functional resistance against further Xoo inoculation In order to understand the molecular events associated with cellulase induced HR in rice, whole genome transcriptional profiling was performed using Affymetrix Rice GeneChips Keywords: Expression profiling of a hypersensitive reaction like response
Project description:The study of natural genetic variation for plant disease resistance responses is a complementary approach to utilizing mutants to elucidate genetic pathways. While some key genes involved in pathways controlling disease resistance, and signaling intermediates such as salicylic acid (SA) and jasmonic acid (JA), have been identified through mutational analyses, the use of genetic variation in natural populations permits the identification of change-of-function alleles, which likely act in a quantitative manner. Whole genome microarrays, such as Affymetrix GeneChips, allow for molecular characterization of the disease response at a genomics level and characterization of differences in gene expression due to natural variation. Differences in the level of gene expression, or expression level polymorphisms (ELPs), can be mapped in a segregating population to identify regulatory quantitative trait loci (expression QTLs, e-QTLs) affecting host resistance responses. We assessed Arabidopsis accessions Bayreuth-0 (Bay-0) and Shahdara (Sha) for natural variation in the response to SA. We treated vegetatively grown plants with either SA or a control solution (Silwet), and harvested the plants 4, 28, or 52 hours after chemical treatment. We present Affymetrix GeneChip microarray expression data for 2 biological replications of the control (Silwet) samples for Bay-0 and Sha. These GeneChips were used to generate genetic markers which allowed the development of high-density haplotype maps of a Bay-0 x Sha RIL population.
Project description:The study of natural genetic variation for plant disease resistance responses is a complementary approach to utilizing mutants to elucidate genetic pathways. While some key genes involved in pathways controlling disease resistance, and signaling intermediates such as salicylic acid (SA) and jasmonic acid (JA), have been identified through mutational analyses, the use of genetic variation in natural populations permits the identification of change-of-function alleles, which likely act in a quantitative manner. Whole genome microarrays, such as Affymetrix GeneChips, allow for molecular characterization of the disease response at a genomics level and characterization of differences in gene expression due to natural variation. Differences in the level of gene expression, or expression level polymorphisms (ELPs), can be mapped in a segregating population to identify regulatory quantitative trait loci (expression QTLs, e-QTLs) affecting host resistance responses. We assessed Arabidopsis accessions Bayreuth-0 (Bay-0) and Shahdara (Sha) for natural variation in the response to JA. We treated vegetatively grown plants with either JA or a control solution (Silwet), and harvested the plants 4, 28, or 52 hours after chemical treatment. We present Affymetrix GeneChip microarray expression data for 2 biological replications of the control (Silwet) samples for Bay-0 and Sha. These GeneChips were used to generate genetic markers which allowed the development of high-density haplotype maps of a Bay-0 x Sha RIL population.
Project description:The study of natural genetic variation for plant disease resistance responses is a complementary approach to utilizing mutants to elucidate genetic pathways. While some key genes involved in pathways controlling disease resistance, and signaling intermediates such as salicylic acid (SA) and jasmonic acid (JA), have been identified through mutational analyses, the use of genetic variation in natural populations permits the identification of change-of-function alleles, which likely act in a quantitative manner. Whole genome microarrays, such as Affymetrix GeneChips, allow for molecular characterization of the disease response at a genomics level and characterization of differences in gene expression due to natural variation. Differences in the level of gene expression, or expression level polymorphisms (ELPs), can be mapped in a segregating population to identify regulatory quantitative trait loci (expression QTLs, e-QTLs) affecting host resistance responses. We assessed Arabidopsis accessions Bayreuth-0 (Bay-0) and Shahdara (Sha) for natural variation in the response to SA. We treated vegetatively grown plants with either SA or a control solution (Silwet), and harvested the plants 4, 28, or 52 hours after chemical treatment. We present Affymetrix GeneChip microarray expression data for 2 biological replications of the SA-treated samples for Bay-0 and Sha. The GeneChip microarray expression data for the control (Silwet-treated) samples was submitted as E-TABM-61. Normalized data is not provided here as the normalization step was included in the data statistical analsyses - for more information please contact the experiment provider.
Project description:The study of natural genetic variation for plant disease resistance responses is a complementary approach to utilizing mutants to elucidate genetic pathways. While some key genes involved in pathways controlling disease resistance, and signaling intermediates such as salicylic acid (SA) and jasmonic acid (JA), have been identified through mutational analyses, the use of genetic variation in natural populations permits the identification of change-of-function alleles, which likely act in a quantitative manner. Whole genome microarrays, such as Affymetrix GeneChips, allow for molecular characterization of the disease response at a genomics level and characterization of differences in gene expression due to natural variation. Differences in the level of gene expression, or expression level polymorphisms (ELPs), can be mapped in a segregating population to identify regulatory quantitative trait loci (expression QTLs, e-QTLs) affecting host resistance responses. We assessed Arabidopsis accessions Bayreuth-0 (Bay-0) and Shahdara (Sha) for natural variation in the response to JA. We treated vegetatively grown plants with either JA or a control solution (Silwet), and harvested the plants 4, 28, or 52 hours after chemical treatment. We present Affymetrix GeneChip microarray expression data for 2 biological replications of the JA-treated samples for Bay-0 and Sha. The GeneChip microarray expression data for the control (Silwet) samples was submitted as E-TABM-60. Normalized data is not provided here as the normalization step was included in the data statistical analsyses - for more information please contact the experiment provider.
Project description:The study of natural genetic variation for plant disease resistance responses is a complementary approach to utilizing mutants to elucidate genetic pathways. While some key genes involved in pathways controlling disease resistance, and signaling intermediates such as salicylic acid and jasmonic acid, have been identified through mutational analyses, the use of genetic variation in natural populations permits the identification of change-of-function alleles, which likely act in a quantitative manner. Whole genome microarrays, such as Affymetrix GeneChips, allow for molecular characterization of the disease response at a genomics level and characterization of differences in gene expression due to natural variation. Differences in the level of gene expression, or expression level polymorphisms (ELPs), can be mapped in a segregating population to identify regulatory quantitative trait loci (expression QTLs) affecting host resistance responses. In order to identify an appropriate RIL population to map QTL controlling disease resistance responses, we performed a parental survey of 7 different Arabidopsis accessions. We treated vegetatively grown plants with either salicylic acid or a control solution, and harvested the plants at 3 different time points after chemical treatment. We present Affymetrix GeneChip microarray expression data for 3 biological replications of this parental survey
Project description:tri38-lar - hr - Analyse the transcriptome of Arabidopsis thaliana plants developing localized acquired resistance (LAR) and a hypersensitive response (HR). The goal is to identify genes inducing LAR and/or HR. Here, we want to analyse the transcriptome of Arabidopsis thaliana developing HR. To achieve this, we used Col0 leaf tissues developing an HR reaction after inoculation of the avirulent strain of PstDC3000 carrying the gene avrRpm1. Keywords: normal vs disease comparison
Project description:The study of natural genetic variation for plant disease resistance responses is a complementary approach to utilizing mutants to elucidate genetic pathways. While some key genes involved in pathways controlling disease resistance, and signaling intermediates such as salicylic acid (SA) and jasmonic acid (JA), have been identified through mutational analyses, the use of genetic variation in natural populations permits the identification of change-of-function alleles, which likely act in a quantitative manner. Whole genome microarrays, such as Affymetrix GeneChips, allow for molecular characterization of the disease response at a genomics level and characterization of differences in gene expression due to natural variation. Differences in the level of gene expression, or expression level polymorphisms (ELPs), can be mapped in a segregating population to identify regulatory quantitative trait loci (expression QTLs, eQTLs) affecting host resistance responses. We surveyed recombinant inbred lines (RILs) from a population derived from a cross of inbred Arabidopsis accessions Bayreuth-0 (Bay-0) and Shahdara (Sha) in order to map eQTLs controlling ELPs. We treated vegetatively grown plants with either SA or a control solution (Silwet), and harvested the plants 28 hours after chemical treatment. Here we present Affymetrix GeneChip microarray expression data for 8 biological replications of the control (Silwet) samples for Bay-0 and Sha.