Project description:E4F1 is a ubiquitously expressed zinc-finger protein of the Gli-Kruppel family that was first identified, more than 30 years ago, as a cellular target of the adenoviral oncoprotein E1A13S (Ad type V), required for transcriptional regulation of adenoviral genes. In order to identify the p53-independent program controlled by E4F1, we performed microarray analyses in p53 KO and p53 KO; Ha-RasV12-transformed mouse embryonic fibroblasts (MEFs) in wild type and E4F1-inactivated cells. To address p53-independent E4F1 transcriptome, a 12 chip array study has been realized using total RNA recovered from wild-type (E4F1+/flox, CRE infected; odd Samples) MEFs and E4F1-depleted (E4F1-/flox, CRE infected; even Samples) MEFs in p53-/- (Samples 1 to 12) and p53-/-, Ha-RasV12 background (Samples 13 to 24). p53-/- MEFs were derived from 13.5-day mouse embryos. Transformed p53-/- MEFs were generated by infection with a recombinant retrovirus encoding for Ha-RasV12. Three independent biological replicates of wild-type and knock-out MEFs for E4F1 have been used on the two genetic backgrounds.
Project description:E4F1 is a ubiquitously expressed zinc-finger protein of the Gli-Kruppel family that was first identified, more than 30 years ago, as a cellular target of the adenoviral oncoprotein E1A13S (Ad type V), required for transcriptional regulation of adenoviral genes. In order to identify the p53-independent program controlled by E4F1, we performed microarray analyses in p53 KO and p53 KO; Ha-RasV12-transformed mouse embryonic fibroblasts (MEFs) in wild type and E4F1-inactivated cells.
Project description:E4F1 is a ubiquitously expressed zinc-finger protein of the Gli-Kruppel family that was first identified, more than 30 years ago, as a cellular target of the adenoviral oncoprotein E1A13S (Ad type V), required for transcriptional regulation of adenoviral genes. In order to decipher E4F1 cellular target genes, we performed chromatin immunoprecipitation of endogenous E4F1 in primary and in p53KO, Ha-RasV12-transformed MEFs. Both input and immunoprecipitated DNA were exhaustively sequenced and mapped on the mouse genome (mm9). Peak detection has been achieved by combining two peak calling algorithms. Intersection of the two E4F1 peak lists on each cell line were considered as E4F1 chromatin bound regions.
Project description:E4F1 is a ubiquitously expressed zinc-finger protein of the Gli-Kruppel family that was first identified, more than 30 years ago, as a cellular target of the adenoviral oncoprotein E1A13S (Ad type V), required for transcriptional regulation of adenoviral genes. In order to decipher E4F1 cellular target genes, we performed chromatin immunoprecipitation of endogenous E4F1 in primary and in p53KO, Ha-RasV12-transformed MEFs. Both input and immunoprecipitated DNA were exhaustively sequenced and mapped on the mouse genome (mm9). Peak detection has been achieved by combining two peak calling algorithms. Intersection of the two E4F1 peak lists on each cell line were considered as E4F1 chromatin bound regions. Genome-wide mapping of E4F1 binding in mouse embryonic fibroblasts.
Project description:Oncogenic stress-induced senescence initially inhibits tumor initiation by blocking proliferation. If these cells are not eliminated they may resume proliferation upon loss-of-tumor suppressors, and be at risk of transformation. During tumor formation, depending on the sequence of events of gain-of-oncogenes and/or loss-of-tumor suppressors, cancer cells may emerge from senescent cells. The goal of this study is to determine if transformed cells after senescence (TS) display more aggressive tumorigenic features, with a greater capacity to migrate and a higher resistance to anti-tumoral drugs than cells having undergone transformation without senescence. Here, we modeled cell transformation using mouse embryonic fibroblasts (MEFs) subjected to an inverse sequence of events: i) gain-of-RasV12 oncogene and loss-of-p53 tumor suppressor, leading to transformed cells after senescence (TS), or ii) the opposite, resulting in transformed (T) non-senescent cells.
Project description:Nucleolus-associated DNA was isolated from MEF cells before and after conditional knock-out of UBF and hybridized against genomic DNA in biological replicates. Two different types of immortalized MEF cells were used. MEFs were immortalized by genetic depletion of p53, iMEFs were immortalized by transfection of the SV40 Tt antigen.
