Gene expression data of fibroblasts transduced with LacZ or p63+KLF4.
Ontology highlight
ABSTRACT: To determine if fibroblasts could be reprogrammed to a keratinocyte phenotype p63+KLF4 or LacZ expressing retroviruses were transduced into primary human neonatal fibroblasts. Global gene expression profiling using U133 plus 2.0 arrays were used to deteremine the extent of reprogramming to a keratinocyte phenoypte upon transduction with p63+KLF4. Fibroblasts transduced with p63+KLF4 were also treated +/- high calcium to determine if treatment with calcium could induce differentiation of these cells. Microarray analysis was also performed on cells treated +/- calcium. For gene expression profiling, cultured human fibroblasts were infected with LacZ or p63+KLF4 expressing retroviruses. p63+KLF4 cells were also treated +/- calcium. Microarray analysis using Affymetrix HG-U133 2.0 plus arrays was performed on duplicate samples.
Project description:1. Keratinocytes infected with retroviruses expressing control or SNAI2 shRNAs were cultured in growth medium and Affymetrix HG-U133 plus 2.0 arrays were used to determine global gene expression profiles. 2. Keratinocytes infected with retroviruses overexpressing LACZ or SNAI2 were cultured in growth medium and Affymetrix HG-U133 plus 2.0 arrays were used to determine global gene expression profiles. Keratinocytes with knockdown or overexpression of SNAI2 were used to determine gene expression profiles
Project description:Stem and progenitor cells maintain the tissue they reside in for life by regulating the balance between proliferation and differentiation. How this is done is not well understood. Here, we report that the human exosome maintains progenitor cell function. The expression of several subunits of the exosome were found to be enriched in epidermal progenitor cells, which were required to retain proliferative capacity and to prevent premature differentiation. Loss of PM/Scl-75 also known as EXOSC9, a key subunit of the exosome complex, resulted in loss of cells from the progenitor cell compartment, premature differentiation, and loss of epidermal tissue. EXOSC9 promotes self-renewal and prevents premature differentiation by maintaining transcript levels of a transcription factor necessary for epidermal differentiation, GRHL3, at low levels through mRNA degradation. These data demonstrate that control of differentiation specific transcription factors through mRNA degradation is required for progenitor cell maintenance in mammalian tissue. Refer to publication (Mistry et. Cell Stem Cell 2012) for more detail For gene expression profiling, cultured primary human keratinocytes were knocked down for EXOSC9, EXOSC9 and GRHL3, or control. RNA was harvested from the cells 5 days after knockdown. Microarray analysis using Affymetrix HG-U133 2.0 plus arrays was performed on duplicate samples. Significantly changed genes were identified as previously described(Sen et al., 2010).
Project description:NFkB is a family of transcriptional factors that are responsible for inflammatory and immune gene expression. RelA, RelB and cRel are the transactivation domain containing family members. P50 encoded by Nfkb1 is the primary dimerization partner. Many NFkB deficient mice are embryonic lethal. In order to identify NFkB dependent genes, MEF were isolated from Rela-/-cRel-/-, Rela-/-cRel-/-Nfkb1-/- and Rela-/-Relb-/-cRel-/- embryos at E12.5. They were treated with 100ng/ml LPS for 1hr and then profiled gene expression by microarray.
Project description:The first described feedback loop of the Arabidopsis circadian clock is based on reciprocal regulation between TOC1 and CCA1/LHY. CCA1 and LHY are MYB transcription factors that bind directly to the TOC1 promoter to negatively regulate its expression. Conversely, the activity of TOC1 has remained less well characterized. Genetic data supports that TOC1 is necessary for the reactivation of CCA1/LHY, but there is little description of its biochemical function. Here we show that TOC1 occupies specific genomic regions in the CCA1 and LHY promoters. Purified TOC1 binds directly to DNA through its CCT domain, which is similar to known DNA binding domains. Chemical induction and transient overexpression of TOC1 in Arabidopsis seedlings cause repression of CCA1/LHY expression demonstrating that TOC1 can repress direct targets, and mutation or deletion of the CCT domain prevents this repression showing that DNA binding is necessary for TOC1 action. Furthermore, we use the Gal4/UAS system in Arabidopsis to show that TOC1 acts as a general transcriptional repressor, and that repression activity is in the Pseudoreceiver (PR) domain of the protein. To identify the genes regulated by TOC1 on a genomic scale, we couple TOC1 chemical induction with microarray analysis and identify new potential TOC1 targets and output pathways. Together these results define the biochemical action of the core clock protein TOC1 and refine our perspective on how plant clocks function. Keywords: Expression profiling by array wild type (Col-0) and ALC::TOC1 were sown on Murashige-Skoog with 0.8% agar, stratified for 48 hours and grown in12:12 light:dark (LD) for 12 days and either left in LD or transferred to constant light (LL) and then grown for one more day before the start of the experiment. Tissue was submerged in Murashige-Skoog media supplemented with 2.5% ethanol or no ethanol (mock) and with 20mM MG132 for 3 hours and harvested at ZT1. Three replicates each of the seedlings were collected and frozen in liquid nitrogen.
Project description:To determine if fibroblasts could be reprogrammed to a keratinocyte phenotype p63+KLF4 or LacZ expressing retroviruses were transduced into primary human neonatal fibroblasts. Global gene expression profiling using U133 plus 2.0 arrays were used to deteremine the extent of reprogramming to a keratinocyte phenoypte upon transduction with p63+KLF4. Fibroblasts transduced with p63+KLF4 were also treated +/- high calcium to determine if treatment with calcium could induce differentiation of these cells. Microarray analysis was also performed on cells treated +/- calcium.
Project description:We report changes in enrichment at chromatin of p63, KLF4 and H3K27ac following ectopic expression of wildtype or mutant p63+/- KLF4 for 72 hours in dermal BJ fibroblasts.
Project description:Cell fate transitions are accompanied by global transcriptional, epigenetic and topological changes driven by transcription factors (TFs), as is strikingly exemplified by reprogramming somatic cells to pluripotent stem cells (PSCs) via expression of OCT4, KLF4, SOX2 and cMYC. How TFs orchestrate the complex molecular changes around their target gene loci in a temporal manner remains incompletely understood. Here, using KLF4 as a paradigm, we provide the first TF-centric view of chromatin reorganization and its association to 3D enhancer rewiring and transcriptional changes of linked genes during reprogramming of mouse embryonic fibroblasts (MEFs) to PSCs. Inducible depletion of KLF factors in PSCs caused a genome-wide decrease in the connectivity of enhancers, while disruption of individual KLF4 binding sites from PSC-specific enhancers was sufficient to impair enhancer-promoter contacts and reduce expression of associated genes. Our study provides an integrative view of the complex activities of a lineage-specifying TF during a controlled cell fate transition and offers novel insights into the order and nature of molecular events that follow TF binding.
Project description:We report here genome wide identification of p63 binding sites in cycling neonatal foreskin keratinocytes using high throughput sequencing of ChIP enriched DNA. Analysis of gene ontology, database mining with integration with publicly available data, reveals a role for p63 in transcriptional regulation of multiple genes genetically linked to cleft palate. In addition, we identify AP-2α, a transcription factor which, when mutated, also results in craniofacial clefting syndrome, as a co-regulator of p63 responsive genes. Examination of p63 binding sites in neonatal foreskin keratinocytes
Project description:The transcriptional basis for disrupted epidermal differentiation arising from TP63 AEC mutations remains to be elucidated. Here we present an organotypic model of AEC dysfunction that phenocopies differentiation defects observed in AEC patient skin. Transcriptional analysis of model AEC tissue revealed impaired induction of differentiation regulators, including OVOL1, GRHL3, KLF4, PRDM1 and ZNF750. Genome wide binding analyses of TP63 during epidermal differentiation showed direct binding of OVOL1, GRHL3, and ZNF750 promoters suggesting AEC mutants prevent normal activation of these targets by direct transcriptional interference. Remarkably, exogenous ZNF750 restores impaired epidermal differentiation caused by AEC mutation. Thus, repression of ZNF750 is central to disrupted epidermal differentiation in model AEC tissue. ChIP-Seq analysis: Examination of p63 binding in proliferating and differentiating human keratinocytes
Project description:Tightly controlled gene expression orchestrated by the transcription factor p63 during epithelial differentiation is important for development of epithelial-related structures such as epidermis, limb and craniofacial regions. How p63 regulates spatial and temporal expression of its target genes during these developmental processes is however not yet clear. By epigenomics profiling in stem cells established from one of these epithelial structures, the epidermis, we provide a global map of p63-bound regulatory elements that are categorized as single enhancers and clustered enhancers during epidermal differentiation. Transcriptomics analysis shows dynamic gene expression patterns during epidermal differentiation that correlates with the activity of p63-bound enhancers rather than with p63 binding itself. Only a subset of p63-bound enhancers is active in epidermal stem cells, and inactive p63-bound enhancers appear to function in gene regulation during the development of other epithelial tissues. Our data suggest a paradigm that p63 bookmarks genomic loci during the commitment of the epithelial lineage and regulates gene expression in different epithelial tissues through tissue-specific active enhancers. The catalogue of differentially expressed epidermal genes including non-coding RNAs and epithelial enhancers reported here provides a rich resource for studies of epithelial development and related diseases. Different stages of keratinocyte differentiation