Project description:LAP-35 and SK-N_MC cells were treated with 10 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with SK-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in SK-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in SK-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of SK-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in SK-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression. Three biological replicates were labeled in direct and dye-swap microarray experiments and hybridized onto an Agilent custom splicing-sensitive microarray platform
Project description:human hepatoma Hep3B cells were treated with 40 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with Hep3B_UV_40J-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in Hep3B_UV_40J-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in Hep3B_UV_40J-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of Hep3B_UV_40J-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in Hep3B_UV_40J-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression. Three biological replicates were labeled in direct and dye-swap microarray experiments and hybridized onto an Agilent custom splicing-sensitive microarray platform
Project description:LAP-35 and SK-N_MC cells were treated with 10 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with SK-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in SK-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in SK-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of SK-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in SK-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression.
Project description:human hepatoma Hep3B cells were treated with 10 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with Hep3B_UV_40J-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in Hep3B_UV_40J-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in Hep3B_UV_40J-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of Hep3B_UV_40J-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in Hep3B_UV_40J-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression.
Project description:human hepatoma Hep3B cells were treated with 40 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with Hep3B_UV_40J-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in Hep3B_UV_40J-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in Hep3B_UV_40J-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of Hep3B_UV_40J-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in Hep3B_UV_40J-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression.
Project description:Transcriptional profiling of HepG2 cells treated with UVC (254 nm) for 30 seconds and transduced with Adenoviral vector carrying the Hepatitis B Virus HBx gene vs Adenoviral vector control under UV treatment Experiment Overall Design: One-condition experiment, AdHBx (experimental) UV vs AdEasy (vector control) UV. HepG2 cells were infected with either recombinant HBx adenoviruses (AdHBx) or control adenoviruses (AdEasy). Seventy-two hours later, infected cells were exposed for 30 seconds to UVC (254 nm) irradiation with a germicidal lamp calibrated to deliver 8 or 16 J/m2. Cells were then harvested for either ChIP-chip profiling or expression microarray profiling