Project description:SF-1 is a nuclear receptor transcription factor playing a key role in adrenogonadal development and in adrenocortical tumorigenesis when overexpressed. NRSF/REST is a transcriptional repressor that represses expression of neuronal genes in non-neural tissues. Some data suggest that SF-1 and NRSF/REST can functionally interact in adrenocortical cancer cells. We studied gene expression profiles using Affymetrix microarrays in the H295R/TR SF-1 adrenocortical cancer cell line. In this cell line, SF-1 expression can be increased in a doxycycline-dependent manner (Mol. Endocrinol. 21: 2968–2987, 2007). The effects of a control siRNA and sRNAs specific for SF-1 and for NRSF/REST (in basal or increased SF-1 expression conditions) on gene expression were measured. In H295R/TR SF-1 cells SF-1 and NRSF/REST (in conditions of basal and increased SF-1 dosage) expression were knocked down by Amaxa nucleofection. RNA was extracted and hybridized to Human Gene 1.0 ST Affymetrix microarrays.
Project description:The goal of this study was to identify genomic binding sites of the NRSF/REST transcription factor under conditions of basal and increased SF-1 dosage in the H295R human adrenocortical tumor cell line. 4 samples: input DNA (2 replicates) - NRSF/REST ChIP basal SF-1 dosage - NRSF/REST ChIP increased SF-1 dosage
Project description:SF-1 is a nuclear receptor transcription factor playing a key role in adrenogonadal development and in adrenocortical tumorigenesis when overexpressed. NRSF/REST is a transcriptional repressor that represses expression of neuronal genes in non-neural tissues. Some data suggest that SF-1 and NRSF/REST can functionally interact in adrenocortical cancer cells. We studied gene expression profiles using Affymetrix microarrays in the H295R/TR SF-1 adrenocortical cancer cell line. In this cell line, SF-1 expression can be increased in a doxycycline-dependent manner (Mol. Endocrinol. 21: 2968–2987, 2007). The effects of a control siRNA and sRNAs specific for SF-1 and for NRSF/REST (in basal or increased SF-1 expression conditions) on gene expression were measured.
Project description:The goal of this study was to identify genomic binding sites of the NRSF/REST transcription factor under conditions of basal and increased SF-1 dosage in the H295R human adrenocortical tumor cell line.
2013-08-01 | GSE49014 | GEO
Project description:NRSF/REST knockdown, and SF-1 overexpression and knockdown
Project description:Identification of NRSF/REST genomic binding sites in conditions of basal and increased SF-1 dosage in the H295R adrenocortical tumor cell line
Project description:SF-1 (NR5A1) was overexpressed (Over) or knocked down with shRNA (shRNA) in NCI-H295R human adrenocortical tumor cells and differential global gene expression analysed 48 hours later using Affymetrix GeneChip Human Gene 1.0ST arrays. Over: 5 million cells were transfected (Amaxa Nucleofection) with 10 ug of a pIRES2-AcGPF1-Nuc construct co-expressing SF-1 cDNA and GFP. For experimental control, a mutagenized pIRES2 construct, bearing the G35E mutation in SF-1 that impairs its transactivation function in vivo and in vitro was used. shRNA: 5 million cells were transfected (Amaxa Nucleofection) with 10 ug of the SureSilencing shRNA Plasmid for Human NR5A1 with GFP marker kit (SABioscience). For experimental control, mismatch constructs provided in the kit were used. In both experiments (Over and shRNA), cells were harvested, prepared, and submitted to fluorescence-activated cell sorting (FACS) in a MoFlo XDP sorter 48 hours after transfection. Viable GFP-expressing cells were pooled and resuspended in TRIzol reagent for RNA extraction. Total RNA was extracted, and RNA quality control performed using a 2100 Bioanalyzer. RNA samples were processed using the Affymetrix GeneChip WT Sense Target Labeling kit, starting with 200 ng total RNA. Four independent Over experiments and five independent shRNA experiments were performed and samples of labeled fragmented cDNA were hybridized to Affymetrix GeneChip Human Gene 1.0 ST Arrays. Based on quality control of array data (R/Bioconductor and Partek Genomics Suite), two Over arrays (one SF-1 wild type and one mutant control) and one shRNA array (mismatch control) were excluded and are not deposited here. Differential gene expression analysis was performed using the limma package in R/Bioconductor. A Benjamini-Hochberg-corrected P value cut-off of 0.05 was used to select significant differentially expressed genes in each setting (Over and shRNA). Finally, results from both analyses were combined to identify a subset of positively-regulated SF-1 target genes in these cells, ie transcripts up-regulated by SF-1 overexpression (Over) and down-regulated by SF-1 knockdown (shRNA). Four SF-1 overexpression experiments (Over; intervention = overexpression of wild type SF-1; control = overexpression of functionally-impaired mutant G35E SF-1) and five SF-1 knockdown experiments (shRNA; intervention = SF-1-specific small hairpin RNA; control = shRNA mismatch control) were performed in NCI-H295R cells. Differential gene expression in each setting was analysed using GeneChip Human Gene 1.0ST arrays. Data for arrays that met quality control are presented here: Over, 3 intervention and 3 control arrays; shRNA, 5 intervention and 4 control arrays. Total of 15 arrays.
Project description:Transcription profiling of transgenic down syndrome mouse model to show the role of DYRK1A gene. The molecular mechanisms that lead to the cognitive defects characteristic of Down syndrome (DS), the most frequent cause of mental retardation, have remained elusive. Here we use a transgenic DS mouse model to show that DYRK1A gene dosage imbalance deregulates chromosomal clusters of genes located near neuron-restrictive silencer factor (REST/NRSF) binding sites. We found that DYRK1A binds the SWI/SNF-complex known to interact with REST/NRSF. Mutation of a REST/NRSF binding site in the promoter of the REST/NRSF target gene L1cam modifies the transcriptional effect of Dyrk1Adosage imbalance on L1cam. DyrkA dosage imbalance perturbs Rest/Nrsf levels with decreased Rest/Nrsf expression in embryonic neurons and increased expression in adult neurons. We identified a coordinated deregulation of multiple genes that are responsible for the cellular phenotypic traits present in DS such as dendritic growth impairment and microcephaly during prenatal cortex development. Dyrk1a overexpression in primary mouse cortical neurons reduced the neuritic complexity. In the postnatal hippocampus, DYRK1A overexpression suppresses a form of synaptic plasticity that may be sufficient to cause DS cognitive defects. We propose that DYRK1A overexpression-related neuronal gene deregulation generates the brain phenotypic changes that characterize DS, with an accessory role for the gene dosage imbalance of other chromosome 21 genes.
Project description:The molecular mechanisms that lead to the cognitive defects characteristic of Down syndrome (DS), the most frequent cause of mental retardation, have remained elusive. Here we use a transgenic DS mouse model to show that DYRK1A gene dosage imbalance deregulates chromosomal clusters of genes located near neuron-restrictive silencer factor (REST/NRSF) binding sites. We found that DYRK1A binds the SWI/SNF-complex known to interact with REST/NRSF. Mutation of a REST/NRSF binding site in the promoter of the REST/NRSF target gene L1cam modifies the transcriptional effect of Dyrk1A-dosage imbalance on L1cam. DyrkA dosage imbalance perturbs Rest/Nrsf levels with decreased Rest/Nrsf expression in embryonic neurons and increased expression in adult neurons. We identified a coordinated deregulation of multiple genes that are responsible for the cellular phenotypic traits present in DS such as dendritic growth impairment and microcephaly during prenatal cortex development. Dyrk1a overexpression in primary mouse cortical neurons reduced the neuritic complexity. In the postnatal hippocampus, DYRK1A overexpression suppresses a form of synaptic plasticity that may be sufficient to cause DS cognitive defects. We propose that DYRK1A overexpression-related neuronal gene deregulation generates the brain phenotypic changes that characterize DS, with an accessory role for the gene dosage imbalance of other chromosome 21 genes.