Project description:This study investigates extent and functional significance of alternative splicing in Arabidopsis thaliana defense against the bacterial pathogen Pseudomonas syringae pv tomato (Pst). We have provided a detailed characterization of the Arabidopsis thaliana transcriptional response to Pseudomonas syringae infection in both susceptible and resistant hosts. We carried out two independent inoculation experiments (biological replicates) for each treatment. Col-0 is susceptible to virulent Pst DC3000 but has a functional RPS4 resistance gene effective against DC3000 expressing AvrRps4
Project description:Arabidopsis G3BP1 mutants showed enhanced resistance to the virulent bacterial pathogen Pseudomonas syringae Pv. tomato. Pathogen resistance was mediated in Atg3bp1 mutants by altered stomatal and apoplastic immunity.
Project description:Transgenic Arabidopsis plants (AGO2::HA:AGO2) were treated with either mock (10 mM MgCl2) or Pseudomonas syringae pv. tomato (Pst) expressing avrRpt2 (R2) at a concentration of 2 x 107 cfu/ml for 14 hours. sRNAs associated with AGO1 and AGO2 were co-immunoprecipitated using antibodies against either AGO1 (AGO1-IP), or HA (hemagglutinin) (AGO2-IP). As controls, we also gel-purified the 18-28 nt fraction of the total RNAs from an AGO2 mutant (ago2-1). The co-immunoprecipitated or gel-purified RNAs were cloned and sequenced by Illumina deep sequencing. Examination of AGO-associated sRNAs in pathogen-treated or control plants
Project description:To prevent activation of plant innate immunity the oomycete pathogen Hyaloperonospora arabidopsidis translocates effector proteins into infected cells of its host Arabidopsis thaliana. We noticed that some H. arabidopsidis effectors, when over-expressed in A. thaliana, render the plant more susceptible to infection by biotrophic pathogens (Fabro et al., 2011, PubMed PMID: 22072967). Here we performed transcriptome profiling of a representative transgenic line constitutively expressing H. arabidopsidis effector HaRxL106. We compared the transcriptomes of A. thaliana wild-type (Col-0) plants and an isogenic line expressing HaRxL106 before pathogen challenge and 24 h after infection with the compatible bacterial pathogen Pseudomonas syringae pv. tomato strain DC3000. HaRxL106 interacts with several Arabidopsis proteins (Mukhtar et al., 2011, PubMed PMID: 21798943; Wirthmueller et al., 2015, PubMed PMID: 25284001). To test whether the HaRxL106-interacting A. thaliana proteins MODIFIER OF SNC1, 6 (MOS6), 6B-INTERACTING PROTEIN 1-LIKE 1 (ASIL1) or RADICAL-INDUCED CELL DEATH1 (RCD1) are altered in their transcriptional response to a biotrophic pathogen we performed transcriptome profiling of mos6-1, asil1-1 and rcd1-1 mutants before and 24 h after infection with P. syringae pv. tomato DC3000.
Project description:The plant innate immunity consists of the two interconnected mechanisms, pattern-triggered immunity (PTI) and effector-triggered immunity (ETI). Although much is known about how plants trigger immune responses upon pathogen recognition, the genetic program by which plants avoid an overshoot in pathogen-triggered immune responses remains largely unknown. Here, we discovered a trihelix transcription factor, GT-3a, as an immune-inducible negative regulator of bacterial resistance in Arabidopsis thaliana. Analysis of public RNA-seq data revealed that GT-3a is specifically induced by ETI activation not by PTI activation. Overexpression of GT-3a suppressed resistance against the bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pto) and Pto-elicited expression of salicylic acid (SA)-responsive genes. Our results suggest that transcriptional induction of GT-3a circumvents the overshooting of SA-mediated defense responses during ETI.
Project description:Pseudomonas syringae pv. phaseolicola (Pph) is a significant bacterial pathogen of agricultural crops, and phage Φ6 and other members of the dsRNA virus family Cystoviridae undergo lytic (virulent) infection of Pph, using the type IV pilus as the initial site of cellular attachment. Despite the popularity of Pph/phage Φ6 as a model system in evolutionary biology, Pph resistance to phage Φ6 remains poorly characterized. To investigate differences between phage Φ6 resistant Pseudomonas syringae pathovar phaseolicola strains, we performed expression analysis of super and non piliated strains of Pseudomonas syringae to determine the genetic cause of resistance to viral infection.
Project description:To identify endogenous siRNAs in response to bacterial pathogen at a whole genome level, we performed small RNA profiling on Pseudomonas syringae-challenged Arabidopsis and obtained more than 24.6 million (M) reads with more than 3.8 M unique small RNAs that perfectly matched Arabidopsis genome. We found some new miRNAs and some miRNA induced by pathogen infection. We also identified more than 20K unique siRNAs from the NAT mRNAs and 22K siRNAs from the introns or intron-exon junction of the NATs.
Project description:Arabidopsis thaliana (Col-0) plants were treated with BABA and gene expression differences to control plants were monitored after dip-inoculation with Pseudomonas syringae pv tomato DC3000. Keywords: transcript profiling, response to BABA-induced priming and infection 3 independant replicates were analyzed by two color co-hybridizations. Leaf RNA from Pseudomonas infected control plants (Cy3 labeled cDNA) was cohybridized with leaf RNA from Pseudomonas infected BABA pretreated plants (Cy5 labeled cDNA). Samples were collected 22 hours after bacterial inoculation. BABA pretreatment was performed two days before bacterial inoculation. To assess the effect of BABA alone on gene expression, leaf RNA from BABA treated plants (Cy5 labeled cDNA) was cohybridized with leaf RNA (Cy3 labeled cDNA) from water treated plants.
