Project description:The aim of the present work was to investigate the effect of monensin on the in vitro growth of T. gondii tachyzoites and on the host cells (human brain microvascular endothelial cells - hBMECs). The hypotheses were that (1) inhibition of the WNT signalling pathway by monensin can reduce the growth of T. gondii infecting human brain microvascular endothelial cells (hBMECs) and (2) by suppression of the growth of T. gondii using monensin, impairment of the BBB integrity can be restored (3) inhibition of WNT pathway by monensin can be detected by microarray experiment.
Project description:In order to better understand how the coccidiocide monensin affects T. gondii, we analyzed the effect of monensin on gene expression of intracellular parasites through microarrays. Overall design: We compared RNA collected either from RH strain tachyzoites 24 hrs after invasion of human foreskin fibroblasts, or 24 hrs after invasion followed by 24 hrs exposure to 2.5ng monensin/ml in tissue culture medium.
Project description:In order to better understand how the coccidiocide monensin affects T. gondii, we analyzed the effect of monensin on gene expression of intracellular parasites through microarrays. We compared RNA collected either from RH strain tachyzoites 24 hrs after invasion of human foreskin fibroblasts, or 24 hrs after invasion followed by 24 hrs exposure to 2.5ng monensin/ml in tissue culture medium.
Project description:We have studied CH1 cells that undergo G1 arrest upon anti-IgM treatment after 16 hrs of stimulation. First we studied the differential gene expression under anti-IgM and IL-4 stimulation condition individually and in combination, and this revealed the affected genes to be directly or indirectly playing a role for arresting the cells in the G1 phase of the cell cycle. We then performed Western blotting experiments for the selected signaling molecule candidates from various pathways, and the phosphorylation kinetic profiles were used to study their role in regulating the gene expression under anti-IgM and/or IL-4 stimulus. Finally, we profiled how the signaling pathways are regulating the activation and deactivation of 345 transcription factors, which are responsible for regulating the anti-IgM and/or IL-4 responsive genes, which in turn leads to the functional output.
Project description:Fusion of the EWS gene to FLI1 produces a fusion oncoprotein that drives an aberrant gene expression program responsible for the development of Ewing sarcoma. We used a homogenous proximity assay to screen for compounds that disrupt the binding of EWS-FLI1 to its cognate DNA targets. A number of DNA-binding chemotherapeutic agents were found to non-specifically disrupt protein binding to DNA. In contrast, actinomycin D was found to preferentially disrupt EWS-FLI1 binding by comparison to p53 binding to their respective cognate DNA targets in vitro. In cell-based assays, low concentrations of actinomycin preferentially blocked EWS-FLI1 binding to chromatin, and disrupted EWS-FLI1-mediated gene expression. Higher concentrations of actinomycin globally repressed transcription. These results demonstrate that actinomycin preferentially disrupts EWS-FLI1 binding to DNA at selected concentrations. Although the window between this preferential effect and global suppression is too narrow to exploit in a therapeutic manner, these results suggest that base-preferences may be exploited to find DNA-binding compounds that preferentially disrupt subclasses of transcription factors. Using proximity assays in A673 Ewing Sarcoma cells, we screened 7 bioactive-enriched small molecule libraries, totaling 5,200 compounds to identify compounds that could disrupt the binding of EWS-FLI1 to its cognate DNA binding sequence. We defined a set of EWS-FLI1-regulated genes by shRNA depletion of EWS-FLI1in the same cell line. Duplicate knock down experiments were carried out and compared to duplicate scrambled shRNA controls. This signature was used to interrogate the effects in duplicate experiments of low- and high-dose actinomycin D treatment in A673 cells as compared to DMSO and untreated controls (2 each).
Project description:Lysine Specific Demethylase 1 (LSD1, KDM1A) functions as a transcriptional corepressor through demethylation of histone 3 lysine 4 (H3K4), but has coactivator function on some genes through unclear mechanisms. We show that LSD1, interacting with CoREST, associates with and coactivates androgen receptor (AR) on a large fraction of androgen-stimulated genes. A subset of these AR/LSD1-associated enhancer sites have histone 3 threonine 6 phosphorylation (H3T6ph), and these sites are further enriched for androgen-stimulated genes. Significantly, despite its coactivator activity, LSD1 still mediates H3K4me2 demethylation at these androgen-stimulated enhancers. FOXA1 is also associated with LSD1 at AR regulated enhancer sites, and a FOXA1 interaction with LSD1 enhances binding of both proteins at these sites. These findings show LSD1 functions broadly as a regulator of AR function, that it maintains a transcriptional repression function at AR-regulated enhancers through H3K4 demethylation, and has a distinct AR-linked coactivator function mediated by demethylation of other substrates. Determine the role of LSD1 in androgen signaling.
Project description:We reported the gene expression profile of T47D cells treated with the organic extract of Particulate matter 2.5 (PM2.5) sampled next to the municipal solid waste incineration plant of Bologna city. Based on a air pollution distribution model that takes the incinaration plant as point source of emission, two sites were chosen to sample particulate matter near incineration plant: "FrulloEst" representing the maximum effect of the incineration plant, "Calamosco" representing the negative control of "FrulloEst" (minimun effect of incineration plant, same effect of other air pollution fonts). Another site, "Giardini Margherita", is chosen to sample the urban background air pollution. for each site sample collection was performed in winter and in summer season.