Comparative transcriptome profiling of transgenic Arabidopsis thaliana lines expressing the Hyaloperonospora arabidopsidis candidate effector HaRxL106 and knock-out mutants of HaRxL106-interacting host proteins
ABSTRACT: 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. Overall design: Five weeks old Arabidopsis plants (Col-0, HaRxL106-overexpressing Col-0 plants, mos6-1, asil1-1 and rcd1-1 mutants) were either left untreated (untreated), infiltrated with P. syringae pv. tomato DC3000 (DC3000) or infiltrated with 10 mM MgCl2 buffer (Mock) at 12:00 (4h after lights on). All samples were harvested 24 hours later for total RNA extraction. mRNA profiles were generated by deep sequencing on Illumina GAIIx using EXPRSS tag-seq protocol. Each biological replicate set of samples were sequenced as one batch (biorep1, biorep2 and biorep3 in filenames).
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:Pathogens target phytohormone signalling pathways to promote disease. Plants deploy salicylic acid (SA) mediated defences against biotrophs. Pathogens antagonise SA immunity by activating jasmonate signalling, e.g. Pseudomonas syringae pv. tomato DC3000 produces coronatine (COR), a jasmonate (JA) mimic. This study found unexpected dynamics between SA, JA and COR and co-operation between JAZ jasmonate repressor proteins during DC3000 infection. JA did not accumulate until late in the infection process and was higher in leaves challenged with coronatine deficient P. syringae or in the more resistant JA receptor mutant coi1. JAZ regulation was complex and coronatine alone was insufficient to sustainably induce JAZs. RNA was extracted from leaves of wild type Col-0 or the jaz5/10 mutant plants from leaves 6, 8, 12 or 16 hours after challenged with Pseudomonas syringae pv. tomato DC3000.
Project description:Arabidopsis thaliana (Col-0) plants were treated with beta-aminobutyric acid (BABA), and gene expression differences to control plants were monitored after infection with Pseudomonas syringae pv tomato DC3000 (Pst DC3000). Keywords: transcript profiling, response to BABA-induced priming and infection 2 independent replicates for each condition were analyzed by two color co-hybridizations. Leaf RNA from Pseudomonas-infected control plants (Cy3-labeled cDNA) 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.
Project description:The Arabidopsis Pathoarray 464_001 (GPL3638) was used to compare response of Col-0, pad4-1 (Zhou et al., 1998; Jirage et al., 1999) and sid2-2 (Wildermuth et al., 2001) to Pseudomonas syringae pv. tomato DC3000 hrcC mutant. SA production is drastically reduced in sid2 mutants. PAD4 is required for SA-mediated responses. The results suggested that the SA increase triggered by MAMPs is one major component in the MAMPs-triggered signaling mechanism. Keywords: Responses of Arabidopsis to Pseudomonas syringae pv. tomato DC3000 hrcC mutant Overall design: This experiment consists of three biological replicates of four samples (mock-inoculated_Col-0, hrcC-inoculated_Col-0_hrcC, hrcC-inoculated_pad4-1 and hrcC-inoculated_sid2-2). For each genotype, two leaves per plant were pooled from three pots to prepare total RNA.
Project description:Pathogen invasion in plants is associated with transcriptional reprogramming. Enigmatically, plants induce similar transcriptome responses upon infection by virulent or avirulent pathogens. This renders the importance of transcriptional reprogramming for immunity obscure. Here, using RNA-seq, we generate time-series transcriptome data coupled with genetic perturbations to reveal temporal dynamics upon infection by virulent or avirulent strains of a bacterial pathogen, Pseudomonas syringae, in Arabidopsis thaliana. Fast and sustained transcriptional reprogramming occurs upon infection with avirulent strains while virulent strain infection leads to a slower response with comparable gene expression patterns and magnitudes. Importantly, transcriptome analysis of resistant and susceptible mutants responding to avirulent strains links delayed transcriptional reprogramming to compromised immunity. Taken together, our results pinpoint the early critical time window of transcriptional reprogramming for establishing effective immunity against the bacterial pathogen. Overall design: Leaves of Col-0 and all the single, double, triple and quadruple mutants of dde2-2, ein2-1, pad4-1, sid2-2 were syringe-infiltrated with mock (water) or suspensions of Pseudomonas syringae pv. tomato DC3000 (Pto DC3000) carrying an empty vector (pLAFR), Pto DC3000 carrying AvrRpt2, or Pto DC3000 carrying AvrRpm1 at the OD600 of 0.001. Similarly, leaves of the rpm1-3 rps2-101C mutant plants were inoculated with mock, Pto DC3000 carrying AvrRpt2 or Pto DC3000 carrying AvrRpm1. Three fully-expanded leaves (leaves 7-9) from three different plants were harvested as a single biological replicate at 1, 2, 3, 4, 6, 9, 12, 16, 20, 24, 36, 48 hours post inoculation (hpi). To generate three biological replicates, three independent experimental trials were carried out, in which plant positions within pots and growth chambers were randomized in order to avoid undesirable systematic effects. For the statistcal analysis, 348 samples (M001-M348) were used.
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 Overall design: 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.
Project description:This experiment analyses the expresssion data of the wild type P. syringae pv. tomato DC3000 compared with its fleQ mutant grown under two different conditions: liquid culture in minimal medium and swarming plates.
Project description:To characterize the PTI response of tomato and the effect of the delivery of a subset of effectors, we performed an RNA-seq analysis of tomato Rio Grande prf3 leaves challenged with either the flgII-28 peptide or the following bacterial strains: Agrobacterium tumefaciens GV2260, Pseudomonas fluorescens 55, Pseudomonas putida KT2440, Pseudomonas syringae pv. tomato (Pst) DC3000, Pst DC3000 deltahrcQ-U deltafliC and Pst DC3000 deltaavrPto deltaavrPtoB. NOTE: Samples in SRA were assigned the same sample accession. This is incorrect as there are different samples, hence “Source Name” was replaced with new values. Comment[ENA_SAMPLE] contains the original SRA sample accessions.