Project description:Transcriptional profiling of wt and ler- EPEC and O157 E. coli strains at mid log and early stationary growth phases wt vs. Ler- at OD 0.3 and 0.9. Biological replicates: 4 independently grown. Four replicates per array.
Project description:We examined global miRNA profiles of 3-weeks old 35S-HA-RICE1 D52A transgeneic plants compared to Ler wild-type using illumina sequencing. We conclude that, in general, both miRNA and miRNA* expression levels are downregulated in catalytically-defective RICE1 transgenic plants compared to Ler wild type.
Project description:In order to identify genes that were differentally regulated upon oral infection with EPEC, we isolated 8 days post-infection intestinal epithelial cells (IECs) from the small intestine of C57BL/6 neonate mice that were left untreated or orally infected with 5x104 WT EPEC E2348/69 or with 5x104 of the isogenic mutant ΔescV on their first day of life.
Project description:Mito-TAILS N-terminomics analysis of proteolytic events during EPEC infection of human epithelial cells, on whole-cell level and mitochondria.
Project description:RIL-seq experiment of EPEC hfq-flag mutant, in activating- conditions:growth on DMEM at 37°C to mid exponential growth phase (e.g., OD600=0.3). In these conditions EPEC strongly expresses its major virulence components, T3SS and BFP, mimicking infection. Non-activating conditions: overnight growth of static culture on LB medium at 37°C where virulence factors are not expressed. RIL-seq experiments are designed to reveal the interactions of sRNA and their targets.
Project description:Ler, a homolog of H-NS in enteropathogenic Escherichia coli (EPEC), plays a critical role in the expression of virulence genes encoded by the pathogenic island, locus of enterocyte effacement (LEE). Although Ler acts as an antisilencer of multiple LEE operons by alleviating H-NS-mediated silencing, it represses its own expression from two LEE1 P1 promoters, P1A and P1B, that are separated by 10 bp. Various in vitro biochemical methods were used in this study to elucidate the mechanism underlying transcription repression by Ler. Ler acts through two AATT motifs, centered at position -111.5 on the coding strand and at +65.5 on the noncoding strand, by simultaneously repressing P1A and P1B through DNA-looping. DNA-looping was visualized using atomic force microscopy. It is intriguing that an antisilencing protein represses transcription, not by steric exclusion of RNA polymerase, but by DNA-looping. We propose that the DNA-looping prevents further processing of open promoter complex (RPO) at these promoters during transcription initiation.
