RNA-seq analysis of Pseudomonas syringae pv. tomato DC3000
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ABSTRACT: This experiment analyses the expression data of the wild type P. syringae pv. tomato DC3000 grown in the absence and in the presence of phloretin and naringenin.
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:affy_syringae_malaga_athaliana - affy_syringae_malaga_athaliana - - Pseudomonas syringae is a plant pathogenic bacterium that relies on a type III secretion system (T3SS) to cause disease in susceptible hosts and to trigger defence in resistant plants. The T3SS translocates effector proteins directly inside the plant cell. Some P. syringae pathovars translocate the effector HopZ1a, which is recognized in Arabidopsis, triggering the hypersensitive response (HR). This resistance does not depend on the usual defence pathways involved in resistance against other avirulence effectors, so it would be very helpful to know the transcriptomic events that take place in the context of a hypersensitive response triggered by HopZ1a. ULP genes codifies for plant SUMO-proteases. Recent studies by our group revealed that they could be involved in plant defense against microorganisms.-- We infiltrated Arabidopsis thaliana ecotype Columbia wild type with 10mM MgCl2 (as mock inoculation), the virulent pathogen Pseudomonas syringae pv. tomato (Pto), Pto expressing the effector HopZ1a and Pto expressing a HopZ1a derivative carrying a point mutation in a residue essential for the cystein-protease activity. We also grew ulp1c/ulp1d mutant plants to analyze them either without treatment or inoculated with MgCl2 (as mock) and Pto wt. Keywords: gene knock out,normal vs antisens mutant comparison 24 arrays - ATH1
Project description:The yeast proteins Pkh1 and Pkh2 are functional counterparts of the mammalian 3-phosphoinositide-dependent protein kinase 1 (PDK1). Cells carrying simultaneous deletion in both genes, PKH1 and PKH2 are not viable, at least in some genetic backgrounds (Casamayor et al., 1999; Inagaki et al., 1999). Consequently, a different strategy is needed to study the function of these apparently redundant gene products. The approach that has been successfully used to dissect the functions of these proteins consist in the use of a strain that combine the disruption of PKH2 with the temperature sensitive pkh1D398G allele (Inagaki et al., 1999). Since Pkh1 and Pkh2 phosphorylate Pkc1 in vitro in its activation loop (Thr983), and the cell lysis defects of the pkh1D398G pkh2 strain at the restrictive temperature are partially restored by constitutive activation of the Pkc1-Slt2 MAPK pathway, it has been suggested that the Pkh activity is important for maintenance of the cell wall integrity in S. cerevisiae (Inagaki et al., 1999; Friant et al., 2001). We considered it necessary that a different genetic strategy would be convenient in order to carry out specific studies about the functions of the Pkh proteins. In order to avoid incubations at temperatures that activate the Slt2 pathway, and induce cellular lysis, we decided to use a strategy based on the use of a regulatable promoter. We replaced 487 bp located immediately upstream the start PKH2 codon by a cassette containing the doxycycline-repressed promoter tetO7. This substitution is positioned in a 1.3 kbp intergenic region containing divergent promoters and it seems unlikely that may affect expression of the IZH4, the upstream gene, which encode a family of four paralogous membrane proteins involved in zinc ion homeostasis and whose expression is regulated by fatty acids and zinc altered levels. In this strain (MB002) the PKH2 expression could be switched off by addition of doxycycline. In order to deplete the cell for the Pkh activity, we disrupted both, the PKH1 and PKH3 coding regions, obtaining the new SDP8 strain. Our results show that depletion of Pkh results in a differential transcriptional response in front of a heat shock stress. The general transcriptional response was attenuated in the SDP8 when compared when WT cells, but lack of Pkh activity did not affect the repression of the ribosomal proteins. Four samples were analyzed: the SDP8 strain, a tetO7 conditional mutant, and its isogenic WT strain both, in the presence and in the absence of doxycyline (for 8 and 24 h). We compared the expression profile of: 1) WT + 16h Dox + 40 min heat shock vs WT + 16h Dox. 2) SDP8 + 16h Dox + 40 min heat shock vs SDP8 + 16h Dox. A Dye-swap was carried out for each comparison of samples. Total number of chips analyzed: 4.
Project description:RNA polymerases deal with obstacles during transcription elongation that need to be removed. One important type of hindrance consists of DNA lesions, which are removed by transcription-coupled repair (TCR). To improve our knowledge of transcription elongation and its coupling to TCR, we performed DNA microarray experiments and used the yeast library of nonessential knock-out mutations to screen for genes conferring resistance to the transcription-elongation inhibitor micophenolic acid and the DNA-damaging agent 4- nitroquinoline-N-oxide. A single sample for each treatment was analyzed.
Project description:Triclosan is a biocidal active agent commonly found in domestic cleaning products, hand sanitizers, cosmetics and personal care products. It is used to control microbial contamination and has a broad-spectrum of activity against many Gram-positive and Gram-negative bacteria. The development of triclosan tolerance with potential cross resistance to clinically relevant antibiotics in zoonotic pathogens is of concern given the widespread use of this active agent in clinical, food processing and domestic environments. Some studies have proposed that an over-dependence on triclosan-containing products could lead to the emergence of clinically important pathogens that are highly tolerant to both biocides and antibiotics. Currently, there is limited understanding of the mechanisms contributing to the emergence of triclosan tolerance in foodborne pathogens at a genetic level. We used microarray analysis to compare gene expression between a wildtype E. coli O157:H19 isolate (WT) with a minimum inhibitory concentration (MIC) to triclosan of 6.25 ug/ml and its laboratory generated triclosan tolerant mutant (M) with a MIC of >8000 ug/ml. Gene expression profiling was performed on untreated E. coli O157:H19 wildtype (WTu) and mutant (Mu), and on the wildtype and mutant treated with 6 ug/ml triclosan for 30 minutes (WTt and Mt respectively). RNA was extracted from three independent biological replicates for WTu, Mu, WTt & Mt for hybridization on Affymetrix GeneChip E. coli Genome 2.0 Arrays. Micorarray analysis including pre-processing, normalisation and statistical analysis were performed using R (R, 2007) version 2.6 and Bioconductor (Gentleman et al. 2004, Genome Biol. 5:R80) version 2.1 as previously described by Morris et al.(2009, Physiol. Genomics 39:28-37).
Project description:The aim of the experiments was to determine the regulon of the Bacillus subtilis alternative sigma factor SigI. Biological relevance: To expand our knowledge about Bacillus subtilis transcriptional network under unfavorable conditions. Experimental workflow overview: Bacillus subtilis 168 trp+ (BaSysBio) was used as the genetic background. (i) sigI-rsgI knock-out, (ii) rsgI knock-out, and (iii) wr strains were cultured in LB medium to mid-exponential phase at 37°C and 52°C. Total RNA was isolated from 3 ml of the culture. rRNA was depleted from the samples with RiboMinus; subsequently RNA-seq libraries were prepared (Illumina compatible NEXTflex Rapid Directional RNA-Seq Kit, Bioo Scientific) and sequenced at the EMBL GeneCore facility. The experiment was performed in three independent replicates.
Project description:Staphylococcus aureus COL wild type strain was cultivated in LB medium in 3 biological replicates and harvested at an OD500 of 0.5 before (as control) and at 30 min after exposure to 1176 μM neutrophil-derived oxidant hypothiocyanous acid (HOSCN) stress. Cells were disrupted in 3 mM EDTA/ 200 mM NaCl lysis buffer with a Precellys24 ribolyzer followed by RNA isolation using the acid phenol extraction protocol as described. The RNA quality was approved by Trinean Xpose (Gentbrugge, Belgium) and the Agilent RNA Nano 6000 kit using an Agilent 2100 Bioanalyzer (Agilent Technologies, Böblingen, Germany). Ribo-Zero rRNA Removal Kit (Bacteria) from Illumina (San Diego, CA, USA) was used to remove the rRNA. TruSeq Stranded mRNA Library Prep Kit from Illumina (San Diego, CA, USA) was applied to prepare the cDNA libraries. The cDNAs were sequenced paired end on an NextSeq 500 (San Diego, CA, USA) using 75 bp read length and a minimum sequencing depth of 8 million reads per library. The paired end cDNA reads were mapped to the Staphylococcus aureus COL genome sequence (accession number CP000046) using bowtie2 v2.2.7 (Langmead and Salzberg, 2012) with default settings for paired-end read mapping. All mapped sequence data were converted from SAM to BAM format with SAMtools v1.3 (Li et al., 2009) and imported to the software ReadXplorer v.2.2 (Hilker et al., 2016).
Project description:The yeast proteins Pkh1 and Pkh2 are functional counterparts of the mammalian 3-phosphoinositide-dependent protein kinase 1 (PDK1). Cells carrying simultaneous deletion in both genes, PKH1 and PKH2 are not viable, at least in some genetic backgrounds (Casamayor et al., 1999; Inagaki et al., 1999). Consequently, a different strategy is needed to study the function of these apparently redundant gene products. The approach that has been successfully used to dissect the functions of these proteins consist in the use of a strain that combine the disruption of PKH2 with the temperature sensitive pkh1D398G allele (Inagaki et al., 1999). Since Pkh1 and Pkh2 phosphorylate Pkc1 in vitro in its activation loop (Thr983), and the cell lysis defects of the pkh1D398G pkh2 strain at the restrictive temperature are partially restored by constitutive activation of the Pkc1-Slt2 MAPK pathway, it has been suggested that the Pkh activity is important for maintenance of the cell wall integrity in S. cerevisiae (Inagaki et al., 1999; Friant et al., 2001). We considered it necessary that a different genetic strategy would be convenient in order to carry out specific studies about the functions of the Pkh proteins. In order to avoid incubation at temperatures that activate the Slt2 pathway, and induce cellular lysis, we decided to use a strategy based on the use of a regulatable promoter. We replaced 487 bp located immediately upstream the start PKH2 codon by a cassette containing the doxycycline-repressed promoter tetO7. This substitution is positioned in a 1.3 kbp intergenic region containing divergent promoters and it seems unlikely that may affect expression of the IZH4, the upstream gene, which encode a family of four paralogous membrane proteins involved in zinc ion homeostasis and whose expression is regulated by fatty acids and zinc altered levels. In this strain (MB002) the PKH2 expression could be switched off by addition of doxycycline. In order to deplete the cell for the Pkh activity, we disrupted both, the PKH1 and PKH1 coding regions, obtaining the new SDP8 strain. Our results show that the long term depletion of Pkh results in a cell transcriptional response that include overexpression of genes typically induced in response to oxidative stress, as well as up-regulation of chaperons and genes that induce the unfolded protein response. Four samples were analyzed: the SDP8 strain, a tetO7 conditional mutant, and its isogenic WT strain both, in the presence and in the absence of doxycyline (for 8 and 24 h). We compared the expression profile of: 1) SDP8 + Dox after 8h vs WT + Dox after 8h 2) SDP8 + Dox after 24h vs WT + Dox after 24h A Dye-swap was carried out for each comparison of samples. Total number of chips analyzed: 4.
Project description:Vesiculation is a process employed by Gram-negative bacteria to release extracellular vesicles (EVs) into the environment. Bacterial EVs contain molecular cargo from the donor bacterium and play important roles in bacterial survival and growth. Here, we describe EV production in plant-pathogenic Pseudomonas syringae pv. tomato DC3000 (Pto DC3000), the causal agent of bacterial speck disease. Cultured Pto DC3000 exhibited EV structures both on the cell surface and in the vicinity of bacterial cells, observed as outer membrane vesicle (OMV) release. We used in-solution trypsin digestion coupled to mass spectrometry to identify 369 proteins enriched in EVs recovered from cultured Pto DC3000. The predicted localization profile of EV proteins supports the production of EVs also in the form of outer-inner-membrane vesicles (OIMVs). EV production varied slightly between bacterial lifestyles and also occurred in planta. The potential contribution of EVs to Pto DC3000 plant infection was assessed using plant treatments and bioinformatic analysis of the EV-enriched proteins. While these results identify immunogenic activities of the EVs, they also point at roles for EVs in bacterial defences and nutrient acquisition by Pto DC3000.
Project description:RNase J1 is the first nuclease with 5’-3’ exonuclease activity in bacteria and plays an important role in the maturation and degradation of mRNA. RNase J1 could also play a role in transcription termination of aberrant complexes. RNase J1 could bind to nascent RNA in such complexes, degrade the nascent RNA, and upon catching up with RNA polymerase (RNAP) dissociate the complex. Similar model was showed in eukaryotes. We did ChIP-seq to confirm our hypothesis.