Project description:We used IMR90 ER:RAS cells infected with an empty vector or an shRNA for ARID1B and induced senescence by addition of 4OHT. 6 days later RNA was collected for gene expression analysis. With a functional screen we previously identified ARID1B as a new regulator of cellular senescence. By performing gene expression analysis we confirmed this finding and showed that knockdown of ARID1B prevents the expression of genes induced during senescence.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression. Two-condition experiment, Normoxic MSCs vs. Hypoxic MSCs.
Project description:We transduced either an empty vector or ARID1B cDNA in IMR90 cells. Cells were selected with puromycin and 6 days after the infection we collected the RNA. ARID1B is a member of the SWI/SNF chromatin-remodeling complex. Our previous experiments showed that knockdown of ARID1B allows cells to bypass cellular senescence. By performing RNA-seq we have shown that ARID1B expression can induce a set of genes involved in the senescence response.
Project description:Mammalian cells possess intrinsic mechanisms to prevent tumorigenesis upon deleterious mutations, including oncogene-induced senescence (OIS). The molecular mechanisms underlying OIS are, however, complex, and remain to be characterized. In this study, we analyzed the changes in the nuclear (phospho)proteome during the progression of OIS. Interestingly, we found that most of the phosphosites regulated during OIS were Prolyl Isomerase Pin1 targets. Our results show that Pin1 is a key regulator of several PML-NB proteins, specifically regulating several proteins upon oncogene activation. We have found that the constitutive PML-NB proteins are significantly regulated when PIN1 is depleted. Furthermore, we show that PIN1 knockdown promotes cell proliferation, while diminishing the senescence phenotype and hallmarks of senescence such as p21. Thus, our data provides preliminary evidence that PML-NB proteins are involved in regulating OIS via phosphorylation, and that the prolyl isomerase PIN1 acts as a tumor suppressor in response to oncogenic ER:RasG12V activation.