The arbitrary luciferase activity per well from a representative of two experiments (n=10/expt) is presented. Z’ was calculated using the SD and mean of luciferase activity from cells infected with Y. enterocolitica WA at MOI 5 versus cells not treated with bacteria (MOI 0) at each time point . The best Z’ value 0.65 was
obtained for the 18 h time point at MOI 5. (B) For the shRNA screen, the kinome plasmid library was transfected in 96 well format, and cells were subjected to puromycin selection to enrich for populations expressing the inhibitory sequences. Chloramphenicol (170 μg/ml) was added 1 h Mizoribine research buy post-infection selleck compound to control extracellular bacteria counts. At 5 h post-infection, 10 ng/ml TNF-α was added to the cells and NF-κB-driven luciferase activity was determined 18 h later. (C) The hit selection cut-off was determined as ≥40%
direct recovery in luciferase signal of Yersinia-infected cells (black squares) relative to non-hits (gray squares) and bacteria free samples (light gray diamonds). (D) The statistical significance of assay hit selection was Fosbretabulin chemical structure evaluated using a standard z-score. Genes in which silencing resulted in assay reads with a score ≥3 standard deviations above the assay mean score were considered to be true hits with Bacterial neuraminidase a strong effect on Yersinia-driven inhibition of NF-κB signaling (shown in black diamonds), compared to non-hits (gray diamonds). We identified 18 kinase genes, that when silenced, led to recovery of NF-κB-mediated luciferase activity in response to Y. enterocolitica infection (Table 1). The screen identified genes
that function in different cellular processes, including signal transduction (e.g., MAP kinases, CKII), cytoskeleton dynamics (e.g. c-KIT, ABL, PAK4), and regulation of ion channel activity (e.g. SGK, WNK). In addition to the kinase shRNA library, we screened a collection of 62 shRNA constructs that targeted 26 genes annotated for chaperone activity to determine whether the heat shock, protein folding, and stress response machinery is required for successful Yersinia infection. We found that silencing of HSPH1, caused recovery of NF-κB regulated gene expression in response to Y. enterocolitica infection (Table 1). Table 1 Host genes identified from shRNAmir kinome screen required for Y.