Translating Dosage Compensation to Trisomy 21
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE47014 | GEO | 2013/07/12
SECONDARY ACCESSION(S): PRJNA203276
REPOSITORIES: GEO
Similar Datasets
Project description:Down syndrome is a common disorder with enormous medical and social costs, caused by trisomy for Chr21. We tested the concept that gene imbalance across an extra chromosome can be de facto corrected in DS patient stem cells by manipulating a single gene, XIST. Using zinc finger nucleases, we targeted a large, inducible XIST transgene into the Chr21 DYRK1A locus, in DS pluripotent stem cells. XIST RNA coats Chr21 and triggers stable heterochromatin modifications, chromosome-wide transcriptional silencing and DNA methylation to form a M-bM-^@M-^\Chr21 Barr Body.M-bM-^@M-^] This provides a model to study human chromosome inactivation and creates a system to investigate genomic expression changes and cellular pathologies of trisomy 21, free from genetic and epigenetic noise. In this study, we used microarrays to understand the genome-wide impacts of inducible XIST expression on Chr21 in trisomy 21 human iPS cell lines, and to evaluate the extent of Chr21 silencing trisomic samples versus a disomic male iPS cell line. Three independently targeted subclones plus the parental Chr21 trisomic (non-targeted) iPS cell line were grown M-BM-1 doxycycline (2 M-BM-5g/ml) for 22 d. Normal male iPS line was also cultured for 22 d and total RNA was extracted with a High Pure RNA extraction kit (Roche) in triplicate for each, processed with a Gene Chip 3M-bM-^@M-^Y IVT Express Kit (Affymetrix), and hybridized to Affymetrix human gene expression PrimeView arrays. Array normalization was performed with Affymetrix Expression Console Software with Robust Multichip Analysis (RMA). Probesets with the top 60% of signal values were considered present and M-bM-^@M-^\expressedM-bM-^@M-^] and were used for all further analysis. In total 9 RNA samples were prepared in triplicate for a total of 27 arrays.
2013-07-12 | E-GEOD-47014 | biostudies-arrayexpress
Project description:Although Down Syndrome (DS) is the leading genetic cause of intellectual disability in children, the developmental pathogenesis remains largely unknown, and better strategies are needed to investigate this. We previously showed that one copy of chromosome 21 can be epigenetically silenced in DS iPSCs by insertion of an XIST transgene, which produces a non-coding RNA that normally silences one X chromosome in female cells. XIST was shown to induce heterochromatin and silence transcription across chromosome 21 in pluripotent stem cells, the natural developmental context of XIST function. Prior literature indicated that initiation of chromosome silencing is only possible within 48 hours of mES cell differentiation, however it would be highly advantageous experimentally if trisomy silencing could be initiated in differentiated cells, and this is critical for any therapeutic potential of XIST. Here we use RNAseq and molecular cytology to investigate the effectiveness of XIST for trisomy silencing in cells undergoing in vitro neural differentiation and examine the potential cell phenotypic effects of chromosomal silencing. Induction of XIST from the onset of differentiation resulted in comprehensive silencing of chromosome 21 genes, providing a powerful approach to examine effects of trisomy on neurogenesis. To determine whether human neural stem cells can initiate XIST-mediated silencing, we induced XIST at several times during neural differentiation. We demonstrate for the first time that differentiated normal human cells can initiate chromosome silencing in response to XIST expression. While this process only takes a few days in pluripotent cells, we show that it takes 2-3 weeks in differentiated cells. Importantly, single-cell RNAseq revealed that cells which express XIST preferentially differentiate into neurons, providing evidence of phenotypic improvement with trisomy silencing, which is seen even when XIST is initiated weeks into differentiation. We are currently investigating whether silenced neurons show other non-chromosome 21 transcriptional changes suggestive of potentially improved function. These studies have important implications for the understanding of XIST biology and DS neurobiology, and also further open the possibility of a chromosomal therapy for DS using a single gene: XIST.
2020-01-23 | GSE125837 | GEO
Project description:Although Down Syndrome (DS) is the leading genetic cause of intellectual disability in children, the developmental pathogenesis remains largely unknown, and better strategies are needed to investigate this. We previously showed that one copy of chromosome 21 can be epigenetically silenced in DS iPSCs by insertion of an XIST transgene, which produces a non-coding RNA that normally silences one X chromosome in female cells. XIST was shown to induce heterochromatin and silence transcription across chromosome 21 in pluripotent stem cells, the natural developmental context of XIST function. Prior literature indicated that initiation of chromosome silencing is only possible within 48 hours of mES cell differentiation, however it would be highly advantageous experimentally if trisomy silencing could be initiated in differentiated cells, and this is critical for any therapeutic potential of XIST. Here we use RNAseq and molecular cytology to investigate the effectiveness of XIST for trisomy silencing in cells undergoing in vitro neural differentiation and examine the potential cell phenotypic effects of chromosomal silencing. Induction of XIST from the onset of differentiation resulted in comprehensive silencing of chromosome 21 genes, providing a powerful approach to examine effects of trisomy on neurogenesis. To determine whether human neural stem cells can initiate XIST-mediated silencing, we induced XIST at several times during neural differentiation. We demonstrate for the first time that differentiated normal human cells can initiate chromosome silencing in response to XIST expression. While this process only takes a few days in pluripotent cells, we show that it takes 2-3 weeks in differentiated cells. Importantly, single-cell RNAseq revealed that cells which express XIST preferentially differentiate into neurons, providing evidence of phenotypic improvement with trisomy silencing, which is seen even when XIST is initiated weeks into differentiation. We are currently investigating whether silenced neurons show other non-chromosome 21 transcriptional changes suggestive of potentially improved function. These studies have important implications for the understanding of XIST biology and DS neurobiology, and also further open the possibility of a chromosomal therapy for DS using a single gene: XIST.
2020-01-23 | GSE125838 | GEO
Project description:To understand the molecular basis of Down syndrome pathogenesis, we performed a transcriptome analysis of nine different tissues in Ts65Dn, an established mouse model of human trisomy 21. Ts65Dn mice have segmental trisomy of mouse chromosome 16 with ca. 128 genes at dosage imbalance (Reeves et al. 1995). The Ts65Dn mouse is widely used as a model for studies of DS because it is at dosage imbalance for the orthologs of about half the 284 Chr21 genes. Ts65Dn mice have several features that directly parallel developmental anomalies of DS. We compare here the expression of 136 mouse orthologs of Chr21 genes, 77 of which are triplicated in Ts65Dn, in trisomic and euploid mice. <br> <br> We designed a mouse cDNA expression array interrogating 136 mmu21 genes. RNA pools from four adult male Ts65Dn mice and four male euploid littermates were prepared from cortex and dissected from three to four month-old mice. Directly labeled first strand cDNA probes from nine different tissues were hybridized to the arrays in replicated hybridizations. A total of 446 genes that are not triplicated in Ts65Dn mice served as controls. These included 62 mmu21 genes from MMU10, MMU17, and non-triplicated portions of MMU16, plus 384 randomly distributed mouse cDNAs from the Unigene collection.
2004-04-23 | E-MEXP-102 | biostudies-arrayexpress
Project description:We have performed genome-wide DNA methylation analysis at single base resolution and gene expression analysis, resulted in hypermethylation in all autosomes in DS samples, mediated by down-regulation of all three TET family genes, and down-regulation of REST/NRSF. Genes located on chr21 were up-regulated by a median of 45% in DS compared to normal villi, while genes with promoter hypermethylation were down regulated. Comparison of RNA expression in human placenta between 5 normal and 4 Trisomy 21 samples.
2013-08-06 | E-GEOD-42142 | biostudies-arrayexpress
Project description:We have performed genome-wide DNA methylation analysis at single base resolution and gene expression analysis, resulted in hypermethylation in all autosomes in DS samples, mediated by down-regulation of all three TET family genes, and down-regulation of REST/NRSF. Genes located on chr21 were up-regulated by a median of 45% in DS compared to normal villi, while genes with promoter hypermethylation were down regulated. DNA methylation comparison in human placenta between 6 normal and 11 Trisomy 21 samples
2013-08-06 | E-GEOD-42074 | biostudies-arrayexpress
Project description:Down syndrome (DS) is caused by an extra copy of chromosome 21. We are characterizing protein changes in human skin fibroblasts. We propose to study corresponding changes at the DNA level (by SNP analysis) and the RNA level (using Affymetrix chips). These studies will detail transcriptional and translational regulation in trisomy. The Specific Aim is to obtain data on RNA transcript levels using Affymetrix expression arrays in a group of trisomy 21 and euploid fibroblast cell lines. In parallel, we will acquire SNP data to determine both genotype (call) and copy number changes for trisomic samples. The results will allow us to identify the patterns of change in a trisomic chromosome (relative to control). [1] We hypothesize that in genomic DNA samples derived from trisomy 21 (TS21) fibroblasts there will be an increased copy number on chr21 with additional microdeletions and microdeletions. [2] We hypothesize that the RNA transcripts derived from chr21 will be elevated relative to euploid controls. [3] We hypothesize that altered RNA transcript levels will be significantly correlated with altered protein levels from these same fibroblast cell lines. The experimental design is as follows. All samples are from deidentified individuals and were obtained from the Brain and Tissue Bank for Developmental Disorders at the University of Maryland, with Johns Hopkins IRB approval.[1] There are five trisomy 21 samples and five euploid samples (total n=10). Fibroblasts were grown in culture to comparable confluency and passage number. Cells were harvested. Total RNA was isolated with a Qiagen kit. The quantity and purity of the RNA was confirmed by spectrophotometry and by electrophoresing an aliquot on a 1% agarose gel. Approximately 10 micrograms of total RNA will be sent to TGen on dry ice for analysis on Affymetrix U133 PlusTwo arrays. Data analysis will be with Affymetrix and Partek software.
2008-06-16 | E-GEOD-9762 | biostudies-arrayexpress
Project description:Down syndrome (DS) is caused by an extra copy of chromosome 21. We are characterizing protein changes in human skin fibroblasts. We propose to study corresponding changes at the DNA level (by SNP analysis) and the RNA level (using Affymetrix chips). These studies will detail transcriptional and translational regulation in trisomy. The Specific Aim is to obtain data on RNA transcript levels using Affymetrix expression arrays in a group of trisomy 21 and euploid fibroblast cell lines. In parallel, we will acquire SNP data to determine both genotype (call) and copy number changes for trisomic samples. The results will allow us to identify the patterns of change in a trisomic chromosome (relative to control). [1] We hypothesize that in genomic DNA samples derived from trisomy 21 (TS21) fibroblasts there will be an increased copy number on chr21 with additional microdeletions and microdeletions. [2] We hypothesize that the RNA transcripts derived from chr21 will be elevated relative to euploid controls. [3] We hypothesize that altered RNA transcript levels will be significantly correlated with altered protein levels from these same fibroblast cell lines. The experimental design is as follows. All samples are from deidentified individuals and were obtained from the Brain and Tissue Bank for Developmental Disorders at the University of Maryland, with Johns Hopkins IRB approval.[1] There are five trisomy 21 samples and five euploid samples (total n=10). Fibroblasts were grown in culture to comparable confluency and passage number. Cells were harvested. Total RNA was isolated with a Qiagen kit. The quantity and purity of the RNA was confirmed by spectrophotometry and by electrophoresing an aliquot on a 1% agarose gel. Approximately 10 micrograms of total RNA will be sent to TGen on dry ice for analysis on Affymetrix U133 PlusTwo arrays. Data analysis will be with Affymetrix and Partek software. Keywords: other
2007-12-04 | GSE9762 | GEO
Project description:Down Syndrome (DS) results from the trisomy of human chromosome 21 (HSA21). It is still the most frequent intellectual disability, affecting 1 newborn per 700 births. Among candidate genes explaining intellectual disabilities seen in DS patients, the dual specificity tyrosine-phosphorylation regulated kinase 1A, DYRK1A, is located in the DS critical region of chromosome 21. DYRK1A has become a major screening target for the development of selective and potent pharmacological inhibitors. We here investigated the effects of a relatively selective DYRK1A inhibitor, Leucettine 41 (hereafter L41) in three different trisomic mouse models with increasing genetic complexity, Tg(Dyrk1a), Ts65Dn and Dp1Yey. Leucettines are derived from the marine sponge alkaloid Leucettamine B.
2018-10-17 | PXD008419 | Pride
Project description:Down syndrome (DS), with trisomy of chromosome 21 (HSA21), is the commonest human aneuploidy. Pre-leukemic myeloproliferative changes in DS fetal livers precedes the acquisition of GATA1 mutations, transient myeloproliferative disorder (DS-TMD) and acute megakaryocytic leukemia (DS-AMKL). Trisomy of the Erg gene is required for myeloproliferation in the Ts(1716)65Dn DS mouse model. We demonstrate here that genetic changes due trisomy of Erg lead to lineage priming of primitive and early multipotential progenitor cells in Ts(1716)65Dn mice, excess megakaryocyte-erythroid progenitors, and malignant myeloproliferation. Correlation of gene expression changes caused by Erg trisomy in Ts(1716)65Dn multilineage progenitor cells with those associated with trisomy 21 in human DS HSCs support a role for ERG as a regulator of hematopoietic lineage potential, trisomy of which drives pre-leukemic changes in DS fetal livers that predispose to subsequent DS-TMD and DS-AMKL.
2015-04-15 | E-MTAB-2574 | biostudies-arrayexpress