Project description:miR6024 overexpression may lead to changes in the transcriptome profile of tomato plants. Further changes may be noticed on infecting these plants with the necrotrophic pathogen Alternaria solani. These changes can only be gauged by carrying out a comparative transcriptome analysis with the wild type plants under similar conditions. We have used tomato (Pusa Ruby) for generation of miR6024 overexpressing transgenics. Disease study on these plants were carried out with the necrotrophic fungus A. solani. We carried an RNA-seq analysis using Illumina hiseq sequencing of 5 RNA libraries created from leaf tissues of wild type, OVX6024 transgenics and A. solani infected wild type and OVX6024 plants. The analysis revealed that 334 and 781 genes were significantly regulated in the transgenic plants and the infected transgenic plants respectively, with respect to their suitable wild type controls. GO enrichment analysis and pathway analysis have been carried out as well. This work is supported by grants from DBT and SERB, GoI.
Project description:MicroRNAs are crucial regulator of reprogramming of gene expression cascade during plant-pathogen interaction. We have used tomato (Pusa Ruby) plant and early blight pathogen, Alternaria for the analysis of tomato miRNA expression profiles in a compatible interaction. Illumina next generation sequencing (NGS) technique based whole transcriptome analysis revealed that, (i) about 188 known miRNAs, ranging from 18nt to 24nt expressed in tomato, which belonged to 124 miRNA families and (ii) both conserved and Solanaceae specific miRNAs were differentially expressed. Most of the miRNAs were down-regulated, and around 7 miRNAs were highly differentially regulated (log2FC ≥ ±3). Furthermore, using stringent selection criteria we could detect approximately 74 putative novel miRNAs. GO terms enrichment and KEGG pathway analyses of predicted targets of differentially expressed miRNAs have been performed to identify the pathways that were perturbed during the infection. Supported by DBT, Govt. of India.
Project description:Plant microRNAs (miRNAs) have been implicated in plant immunity. These mainly focusing Arabidopsis thaliana threatened by (hemi-)biotrophic pathogens such as the bacterial pathogen Pseudomonas syringae. Here, we show that the Arabidopsis miRNA pathway is important for defense responses against the necrotrophic fungus Alternaria brassicicola. The miRNA pathway mutant ago1 exhibits an exaggerated response when treated with A. brassicicola, proposing that AGO1 is positive regulator. We found a subset of Arabidopsis miRNAs that quickly change their expression and their abundance in AGO1 complexes in plants exposed to A. brassicicola. The miRNAs responding to pathogen treatment are mainly targeting genes encoding metabolic enzymes, proteins involved protein degradation or transposons. In case of miR163, A. brassicicola infection results in increased levels of miRNA precursors and preferential accumulation of an unspliced form of pri-miR163, suggesting that A. brassicicola infection changes the transcriptional and post-regulation of pri-miRNAs. miR163 acts as a negative regulator of plant defense because mir163 mutants are more resistant when treated with A. brassicicola. Taken together, our results reveal the existence of positively and negatively acting Arabidopsis miRNA modulating the defense responses against A. brassicicola and highlight the importance of host miRNAs in the interaction between plants and necrotrophic pathogens.
Project description:A major part of plant immune response is mediated by signaling pathways controlled by three hormnes, jasmonate, ethylene, and salicylate. The involvement of each of these hormone signaling pathways in Arabidopsis thaliana was investigated in response to infection of a necrotrophic fungal pathogen, A. brassicicola. Arabideopsis mutants deficient in these hormone signaling pathways were compared to wild type.
Project description:Plant microRNAs (miRNAs) have been implicated in plant immunity. These mainly focusing Arabidopsis thaliana threatened by (hemi-)biotrophic pathogens such as the bacterial pathogen Pseudomonas syringae. Here, we show that the Arabidopsis miRNA pathway is important for defense responses against the necrotrophic fungus Alternaria brassicicola. The miRNA pathway mutant ago1 exhibits an exaggerated response when treated with A. brassicicola, proposing that AGO1 is positive regulator. We found a subset of Arabidopsis miRNAs that quickly change their expression and their abundance in AGO1 complexes in plants exposed to A. brassicicola. The miRNAs responding to pathogen treatment are mainly targeting genes encoding metabolic enzymes, proteins involved protein degradation or transposons. In case of miR163, A. brassicicola infection results in increased levels of miRNA precursors and preferential accumulation of an unspliced form of pri-miR163, suggesting that A. brassicicola infection changes the transcriptional and post-regulation of pri-miRNAs. miR163 acts as a negative regulator of plant defense because mir163 mutants are more resistant when treated with A. brassicicola. Taken together, our results reveal the existence of positively and negatively acting Arabidopsis miRNA modulating the defense responses against A. brassicicola and highlight the importance of host miRNAs in the interaction between plants and necrotrophic pathogens.
Project description:Alternaria brassicae is a necrotrophic fungal pathogen which infects brassica crops and lead to huge loss in crop production. There is a need to exploit the novel resistance mechanism against A. brassicae. Under field condition, chickpea is the potential nonhost plant for A. brassicae. At molecular level, it is not known how the NHR in chickpea operates against A. brassicae. In present study, we did the transcriptomic analysis in chickpea plants exposed to nonhost pathogen, A. brassicae by using microarray. Chickpea plants were spray inoculated with the spore suspension of A. brassicae. The leaf samples were harvested after 24 hpi and 48 hpi from pathogen treated plants and from the mock-treated control plants. The Transcriptome analysis were done from the leaf samples obtained at both the time-points by microarray using Agilent ChickpeaGXP_8X60K chip. Our result suggested the robust transcriptional reprogramming leading to defense response against A. brassicae.
Project description:A major part of plant immune response is mediated by signaling pathways controlled by three hormnes, jasmonate, ethylene, and salicylate. The involvement of each of these hormone signaling pathways in Arabidopsis thaliana was investigated in response to infection of a necrotrophic fungal pathogen, A. brassicicola. Arabideopsis mutants deficient in these hormone signaling pathways were compared to wild type. Expression profiles were obtained from leaves of wild-type (Col-0), dde2-2, ein2-1, and sid2-2 plants at 9 and 24 hours after A. brassicicola inoculation. In addition, expression profiles were obtained from wild-type at 9 and 24 hours after mock inoculation. The replicates were made from three independent experiments (i.e., biological replicates). Please note that 'Col-0 at 24 hpi with A. brassicicola, biological rep 3' was excluded from data processing because the data did not pass a QC based on affyPML of Bioconducter.