Project description:In humans, there are four Ago proteins (Ago1M-bM-^@M-^S4) and AGO1- and 2 were previously implicated in TGS induced by exogenous siRNAs and microRNAs (miRs) directed against gene promoter transcripts via promotion of changes in histone covalent modifications and DNA methylation. Not-with-standing, many mechanistic details of this process remain poorly defined in human cells, and very little is known about the identity of possible endogenous signals, which may drive this process in human cells. Given the evolutionary conserved role of siRNAs and AGO proteins in TGS and heterochromatin formation, we set out to analyse their possible involvement in senesence-associated repression of E2F target genes. To obtain a detailed picture of AGO-immunoprecipitating miRs (RIP) in senescent cells, we used next-generation sequencing (NGS)(RIP-Seq). We also included histone H3 dimethylated on lysine 9 (H3K9me2) in this analysis to assign potential AGO2-interacting miRs to a repressive chromatin state and unfractionated, cellular RNA from senescent cells for normalisation. Determination of AGO AGO-immunoprecipitating miRs in WI-38 senescent human fibroblast
Project description:In humans, there are four Ago proteins (Ago1–4) and AGO1- and 2 were previously implicated in TGS induced by exogenous siRNAs and microRNAs (miRs) directed against gene promoter transcripts via promotion of changes in histone covalent modifications and DNA methylation. Not-with-standing, many mechanistic details of this process remain poorly defined in human cells, and very little is known about the identity of possible endogenous signals, which may drive this process in human cells. Given the evolutionary conserved role of siRNAs and AGO proteins in TGS and heterochromatin formation, we set out to analyse their possible involvement in senesence-associated repression of E2F target genes. To determine, in an unbiased manner, which genes might be under the control of AGO proteins we perfomed genome-wide promoter profiling in senescent and presenescent control WI38 primary fibroblasts applying “ChIP-on-chip” technology using 4 an anti-pan-AGO antibody. DNA from matched genomic inputs and chromatin immunoprecipitation (ChIP) samples were purified, amplified by PCR, and labeled either with Cy3 or Cy5 fluorophores. The labeled DNA from input and ChIP fractions were then combined and hybridised to human promoter arrays containing ~59,000 promoters. determination of AGO binding sites in WI-38 pre-senescent human fibroblast and in senescent human fibroblast
Project description:Senescence in WI-38 cell context was induce by RASv12 over expression Cellular senescence is a permanent cell cycle arrest that is triggered by cancer- initiating or promoting events in mammalian cells and is now considered a major tumour suppressor mechanism. Here, we did a transcriptomic analysis and compared WI-38 contol wich is a human fibroblaste cell line and WI-38 that overexpressed RASv12 a G protein that induce senescence. The goal of our project is to compare transciptomic profile of human growing fibroblast (WI-38 control) and senescent human fibroblast (WI-38 OERAS)
Project description:Senescence in WI-38 cell context was induce by RASv12 over expression Cellular senescence is a permanent cell cycle arrest that is triggered by cancer- initiating or promoting events in mammalian cells and is now considered a major tumour suppressor mechanism. Here, we did a transcriptomic analysis and compared WI-38 contol wich is a human fibroblaste cell line and WI-38 that overexpressed RASv12 a G protein that induce senescence. The goal of our project is to compare transciptomic profile of human growing fibroblast (WI-38 control) and senescent human fibroblast (WI-38 OERAS) Comparaison WI-38 vs WI-38 OE RAS
Project description:RNA-Seq was performed to screen transcripts in whole lyastes or mitoplast fraction prepared from young and senescent WI-38 human fibroblast
Project description:We have identified through high-throughput screen a number of small molecules that promote resistance of human WI-38 cells to hydrogen peroxide. To look into potential mechanism of action for a chalcone hit, we analyzed transcriptional profile by RNA-seq for WI-38 cells treated with this molecule.
Project description:In humans, there are four Ago proteins (Ago1–4) and AGO1- and 2 were previously implicated in TGS induced by exogenous siRNAs and microRNAs (miRs) directed against gene promoter transcripts via promotion of changes in histone covalent modifications and DNA methylation. Not-with-standing, many mechanistic details of this process remain poorly defined in human cells, and very little is known about the identity of possible endogenous signals, which may drive this process in human cells. Given the evolutionary conserved role of siRNAs and AGO proteins in TGS and heterochromatin formation, we set out to analyse their possible involvement in senesence-associated repression of E2F target genes. To obtain a detailed picture of AGO-immunoprecipitating miRs (RIP) in senescent cells, we used next-generation sequencing (NGS)(RIP-Seq). We also included histone H3 dimethylated on lysine 9 (H3K9me2) in this analysis to assign potential AGO2-interacting miRs to a repressive chromatin state and unfractionated, cellular RNA from senescent cells for normalisation.
Project description:Background: Myofibroblasts (MYFs) are generally considered the principal culprits in excessive extracellular matrix deposition and scar formation in the pathogenesis of lung fibrosis. Lipofibroblasts (LIFs), on the other hand, are defined by their lipid-storing capacity and are predominantly found in the alveolar regions of the lung. They have been proposed to play a protective role in lung fibrosis. We previously reported that a LIF to MYF reversible differentiation switch occurred during fibrosis formation and resolution. In this study, we tested whether WI-38 cells, a human embryonic lung fibroblast cell line, could be used to study fibroblast differentiation towards the LIF or MYF phenotype and whether this could be relevant for idiopathic pulmonary fibrosis (IPF). Methods: using WI-38 cells, MYF differentiation was triggered using TGF-β1 treatment and LIF differentiation using Metformin treatment. We analyzed the LIF to MYF and MYF to LIF differentiation by pre-treating the WI-38 cells with TGF-β1 or Metformin first, followed by treatment with Metformin and TGF-β1, respectively. We used IF, qPCR and bulk RNA-Seq to analyze the phenotypic and transcriptomic changes in the cells. We correlated our in vitro transcriptome data from WI-38 cells (obtained via bulk RNA sequencing) with the transcriptomic signature of LIFs and MYFs derived from the IPF cell atlas as well as with our own single-cell transcriptomic data from IFP patients-derived lung fibroblasts (LF-IPF) cultured in vitro. We also carried out alveolosphere assays to evaluate the ability of the proposed LIF and MYF cells to support the growth of alveolar epithelial type 2 cells. Results: WI-38 and LF-IPF display similar phenotypical and gene expression responses to TGF-β1 and Metformin treatment. Bulk RNA-Seq analysis of WI-38 and LF-IPF treated with TGF-β1, or Metformin indicate similar transcriptomic changes. We also show the partial conservation of the LIF and MYF signature extracted from the Habermann et al. scRNA-seq dataset in WI-38 cells treated with Metformin or TGF-β1, respectively. Alveolosphere assays indicate that LIFs enhance organoid growth, while MYFs inhibit organoid growth. Finally, we provide evidence supporting the LIF to MYF reversible switch using WI-38 cells. Conclusions: WI-38 cells represent a versatile and reliable model to study the intricate dynamics of fibroblast differentiation towards the MYF or LIF phenotype associated with lung fibrosis formation and resolution, providing valuable insights to drive future research