Project description:To understand differences of gene expression profiles between Francisella strains RNA profiles of Francisella strains were generated by deep sequencing, in triplicate, using NovaSeq6000. qRT–PCR validation was performed using SYBR Green assays. Our study represents the first detailed differential transcriptomic analysis of Francisella strains , with biologic replicates, generated by RNA-seq technology.
Project description:Francisella possesses a non-canonical T6SS that is essential for efficient phagosomal escape and access to the cytosol of infected macrophages. Using a global and site-specific phosphoproteomic analysis of Francisella we identified here a unique phosphorylation site on IglB, the TssC homologue and a key component of the T6SS contractile sheath. Phosphorylation of the sheath may constitute a previously unrecognized mechanism contributing to the dynamics of assembly-disassembly of the T6SS.
Project description:Francisella possesses a non-canonical T6SS that is essential for efficient phagosomal escape and access to the cytosol of infected macrophages. Using a global and site-specific phosphoproteomic analysis of Francisella we identified here a unique phosphorylation site on IglB, the TssC homologue and a key component of the T6SS contractile sheath. Phosphorylation of the sheath may constitute a previously unrecognized mechanism contributing to the dynamics of assembly-disassembly of the T6SS.
Project description:Comparison of expression profiles of strains of Francisella to identify virulence factors We used custom microarrays to detail the global gene expression of four strains of Francisella (Schu4, LVS, OR960246, U112) and identified distinct classes of differentially expressed genes during this process.
Project description:The goal of this study is to determine the host response of human epithelial cells during infection with Francisella Tularensis. For this purpose, A549 human epithelial cell line was infected with Francisella tularensis spp. holarctica strain LVS for different times of infection, in duplicates. At different times post infection (0.5/1/3/6/12/24 hours post infection) cells were harvested and total RNA was extracted. RNA-seq libraries were constructed and sequencing of 100bp paired-end was performed on the Illumina NovaSeq 6000 system. Sequencing yielded about 22M reads per sample that were mapped to the human genome (Human: GRCh38) resulting with the identification of 21,066 transcripts. The expression of the infected samples was compared to mock sample, and RNA ratios were clustered using partitioning clustering. This approach allowed clustering of the cellular transcripts into 5 distinct classes based on similarities in temporal expression profiles. We next carried out GO term enrichment analysis for each of these five cluster. Our study represents the first detailed analysis of human epithelial response to Francisella tularensis infection, and provide a framework for comparative investigations of genes and mechanisms that may contribute to the infection.
