Using high-density exon arrays to profile gene expression in closely related species
Ontology highlight
ABSTRACT:
ORGANISM(S): Macaca mulatta
SUBMITTER: Yi Xing
PROVIDER: E-GEOD-15666 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Publications
Using high-density exon arrays to profile gene expression in closely related species.
Lin Lan L Liu Song S Brockway Heather H Seok Junhee J Jiang Peng P Wong Wing Hung WH Xing Yi Y
Nucleic acids research 20090527 12
Global comparisons of gene expression profiles between species provide significant insight into gene regulation, evolutionary processes and disease mechanisms. In this work, we describe a flexible and intuitive approach for global expression profiling of closely related species, using high-density exon arrays designed for a single reference genome. The high-density probe coverage of exon arrays allows us to select identical sets of perfect-match probes to measure expression levels of orthologous ...[more]
Similar Datasets
Project description:Global comparisons of gene expression profiles between species provide significant insight into gene regulation, evolutionary processes, and disease mechanisms. In this work, we describe a flexible and intuitive approach for global expression profiling of closely related species, using high-density exon arrays designed for a single reference genome. The high-density probe coverage of exon arrays allows us to select the identical set of perfect-match probes for measuring expression levels of orthologous genes. This eliminates a serious confounding factor in probe affinity effects of species-specific microarray probes, and enables direct comparisons of estimated expression indexes across species. Keywords: analysis of gene expression in tissues We conducted Human Exon 1.0 array profiling of RNAs from three chimpanzee cerebellums and three chimpanzee livers
2009-05-04 | E-GEOD-15626 | biostudies-arrayexpress
Project description:Global comparisons of gene expression profiles between species provide significant insight into gene regulation, evolutionary processes, and disease mechanisms. In this work, we describe a flexible and intuitive approach for global expression profiling of closely related species, using high-density exon arrays designed for a single reference genome. The high-density probe coverage of exon arrays allows us to select the identical set of perfect-match probes for measuring expression levels of orthologous genes. This eliminates a serious confounding factor in probe affinity effects of species-specific microarray probes, and enables direct comparisons of estimated expression indexes across species. Keywords: analysis of gene expression in tissues We conducted Affymetrix Human Exon Junction array (HJAY array) profiling of RNAs from human, chimpanzee and rhesus macaque cerebellums, with three replicates per species.
2010-05-19 | E-GEOD-15665 | biostudies-arrayexpress
Project description:Alternative pre-mRNA splicing is a prevalent mechanism in mammals that promotes proteomic diversity, including expression of cell-type specific protein isoforms. We characterized a role for RBM38 (RNPC1) in regulation of alternative splicing during late erythroid differentiation. We used an affymetrix human exon junction (HJAY) splicing microarray to identify a panel of RBM38-regulated alternatively spliced transcripts. Using microarray databases, we noted high RBM38 expression levels in CD71+ erythroid cells and thus chose to examine RBM38 expression during erythroid differentiation of human hematopoietic stem cells, detecting enhanced RBM38 expression during late erythroid differentiation. In differentiated erythroid cells, we validated a subset of RBM38-regulated splicing events and determined that RBM38 regulates activation of Protein 4.1R (EPB41) exon 16 during late erythroid differentiation. Using Epb41 minigenes, Rbm38 was found to be a robust activator of exon 16 splicing. To further address the mechanism of RBM38-regulated alternative splicing, a novel mammalian protein expression system, followed by SELEX-Seq, was used to identify a GU-rich RBM38 binding motif. Lastly, using a tethering assay, we determined that RBM38 can directly activate splicing when recruited to a downstream intron. Together, our data support the role of RBM38 in regulating alternative splicing during erythroid differentiation. siRNA knockdown of RBM38 was perfomed in human MCF-7 breast cancer cells. The efficiency of RBM38 knockdown was monitored by western blot using an RBM38 antibody (Santa Cruz Biotechnology, SC-85873). We conducted HJAY exon and exon junction array profiling on RNAs from four siRBM38 treated MCF-7 samples vs. four sicontrol treated MCF-7 samples Control / knockdown comparison.
2013-07-29 | E-GEOD-49293 | biostudies-arrayexpress
Project description:Epithelial Splicing Regulatory Proteins 1 and 2 (ESRP1 and ESRP2) are recently discovered epithelial-specific RNA-binding proteins that promote splicing of the epithelial variant of the FGFR2, ENAH, CD44, and CTNND1 transcripts. To catalogue a larger set of splicing events under the regulation of the ESRPs, we profiled splicing changes induced by RNA interference-mediated knockdown of ESRP1 and ESRP2 expression in a human epithelial cell line using the splicing-sensitive Affymetrix Exon ST1.0 Arrays. Analysis of the microarray data using the previously described MADS tool resulted in the identification of over a hundred candidate ESRP-regulated splicing events. We were able to independently validate 37 of these targets by RT-PCR. The ESRP-regulated events encompass all known types of alternative splicing events. Importantly, a number of these regulated splicing events occur in gene transcripts that encode proteins with well-described roles in the regulation of actin cytoskeleton organization, cell-cell adhesion, cell polarity, and cell migration. In sum, this work reveals a novel list of transcripts differentially spliced in epithelial and mesenchymal cells, implying that coordinated alternative splicing plays a critical role in determination of cell type identity. Keywords: control / knockdown comparison Short interfering knockdown of ESRP1 and ESRP2 in human PNT2 prostatic epithelium cells was performed as described before (Warzecha et al., 2009, Molecular Cell 33:591-601). The efficiency of ESRP1 and ESRP2 knockdown was monitored by quantitative RT-PCR as described before (Warzecha et al., 2009, Molecular Cell 33:591-601). In all cases the efficiency of the knockdown was close to 80%. We conducted Exon array profiling on RNAs from four siESRP1/2-treated samples and four siGFP controls.
2010-08-18 | E-GEOD-17468 | biostudies-arrayexpress
Project description:We describe a method, MADS (Microarray Analysis of Differential Splicing), for discovery of differential alternative splicing from exon tiling microarrays. MADS incorporates a series of low-level analysis algorithms motivated by the “probe-rich” design of exon arrays, including background correction, iterative probe selection, and removal of sequence-specific cross-hybridization to off-target transcripts. We used MADS to analyze Affymetrix Exon 1.0 array data on a mouse neuroblastoma cell line after shRNA-mediated knockdown of the splicing factor PTB. From a list of exons with pre-determined inclusion/exclusion profiles in response to PTB depletion, MADS recognized all exons known to have large changes in transcript inclusion levels, and offered improvement over Affymetrix’s analysis procedure. We also identified numerous novel PTB-dependent splicing events. 30 novel events were tested by RT-PCR, and 27 were confirmed. This work demonstrates that the exon tiling microarray design is an efficient and powerful approach for global, unbiased analysis of pre-mRNA splicing. Keywords: control / knockdown comparison Short hairpin knockdown of PTB in mouse N2A neuroblastoma cells was performed as described before (Boutz et al., 2007, Genes Dev 21:1636-1652). The efficiency of the PTB knockdown was monitored by western blot using PTB-NT primary antibody and Cy5 labeled secondary antibody (GE Life Sciences). The blots were imaged using Typhoon 9410 (GE Life Sciences). The band intensities were measured using ImageQuant and normalized to GAPDH. In all cases the efficiency of the knockdown was close to 80% (data not shown). We conducted Exon array profiling on RNAs from three shRNA-PTB treated samples and three mock-treated controls (using empty vectors).
2008-05-09 | E-GEOD-11344 | biostudies-arrayexpress
Project description:Effects of aldosterone on the transcriptome in distal colon. Expression of genes was studied in distal colon surface cells from aldosterone treated vs. vehicle treated rats.
2014-09-01 | E-GEOD-50533 | biostudies-arrayexpress
Project description:A Transcriptome Database for Astrocytes, Neurons, and Oligodendrocytes: A New Resource for Understanding Brain Development and Function Understanding the cell-cell interactions that control CNS development and function has long been limited by the lack of methods to cleanly separate astrocytes, neurons, and oligodendrocytes. Here we describe the first method for the isolation and purification of developing and mature astrocytes from mouse forebrain. This method takes advantage of the expression of S100β by astrocytes. We used fluorescent activated cell sorting (FACS) to isolate EGFP positive cells from transgenic mice that express EGFP under the control of an S100β promoter. By depletion of astrocytes and oligodendrocytes we obtained purified populations of neurons, while by panning with oligodendrocyte-specific antibodies we obtained purified populations of oligodendrocytes. Using GeneChip Arrays we then created a transcriptome database of the expression levels of over 20,000 genes by gene profiling these three main CNS neural cell types at postnatal ages day 1 to 30. This database provides the first global characterization of the genes expressed by mammalian astrocytes in vivo and is the first direct comparison between the astrocyte, neuron, and oligodendrocyte transcriptomes. We demonstrate that Aldh1L1, a highly expressed astrocyte gene, is a highly specific antigenic marker for astrocytes with a substantially broader, and therefore potentially more useful, pattern of astrocyte expression than the traditional astrocyte marker GFAP. This transcriptome database of acutely isolated and highly pure populations of astrocytes, neurons and oligodendrocytes provides a resource to the neuroscience community by providing improved cell type specific markers and for better understanding of neural development, function, and disease. We acutely purified mouse astrocytes from early postnatal ages (P1) to later postnatal ages (P30), when astrocyte differentiation is morphologically complete (Bushong et al., 2004), and acutely purified mouse OL-lineage cells from stages ranging from OPCs to newly differentiated OLs to myelinating OLs. We extracted RNA from each of these highly purified, acutely isolated cell types and used GeneChip Arrays to determine the expression levels of over 20,000 genes and construct a comprehensive database of cell type specific gene expression in the mouse forebrain. Analysis of this database confirms cell type specific expression of many well characterized and functionally important genes. In addition, we have identified thousands of new cell type enriched genes, thereby providing important new information about astrocyte, OL, and neuron interactions, metabolism, development, and function. This database provides a comparison of the genome-wide transcriptional profiles of the main CNS cell types and is a resource to the neuroscience community for better understanding the development, physiology, and pathology of the CNS. Keywords: Developmental CNS Cell type comparision FACS purification of astrocytes: Dissociated forebrains from S100β-EGFP mice were resuspended in panning buffer (DBPS containing 0.02% BSA and 12.5 U/ml DNase) and sequentially incubated on the following panning plates: secondary antibody only plate to deplete microglia, O4 plate to deplete OLs, PDGFRα plate to deplete OPCs, and a second O4 plate to deplete any remaining OLs. This procedure was sufficient to deplete all OL-lineage cells from animals P8 and younger, however, in older animals that had begun to myelinate, additional depletion of OLs and myelin debris was accomplished as follows. The nonadherent cells from the last O4 dish were harvested by centrifugation, and the cells were resuspended in panning buffer containing GalC, MOG, and O1 supernatant and incubated for 15 minutes at room temperature. The cell suspension was washed and then resuspended in panning buffer containing 20 μg donkey anti-mouse APC for 15 minutes. The cells were washed and resuspended in panning buffer containing propidium iodide (PI). EGFP+ astrocytes were then purified by fluorescence activated cell sorting (FACS). Dead cells were gated out using high PI staining and forward light scatter. Astrocytes were identified based on high EGFP fluorescence and negative APC fluorescence from indirect immunostaining for OL markers GalC, MOG, and O1. Cells were sorted twice and routinely yielded >99.5% purity based on reanalysis of double sorted cells.; FACS purification of neurons: EGFP- cells were the remaining forebrain cells after microglia, OLs, and astrocytes had been removed, and were primarily composed of neurons, and to a lesser extent, endothelial cells (we estimate < 4% endothelial cells at P7 and < 20% endothelial cells at P17). EGFP- cells from S100β-EGFP dissociated forebrain were FACS purified in parallel with astrocyte purification and were sorted based on their negative EGFP fluorescence immunofluorescence. Cells were sorted twice and routinely yielded >99.9% purity. In independent preparations, the EGFP- cell population was additionally depleted of endothelial cells and pericytes by sequentially labeling with biotin-BSL1 lectin and streptavidin-APC while also labeling for OL markers as described above. Cells were sorted twice and routinely yielded >99.9% purity.; Panning purification of oligodendrocyte lineage cells: Dissociated mouse forebrains were resuspended in panning buffer. In order to deplete microglia, the single-cell suspension was sequentially panned on four BSL1 panning plates. The cell suspension was then sequentially incubated on two PDGFRα plates (to purify and deplete OPCs), one A2B5 plate (to deplete any remaining OPCs), two MOG plates (to purify and deplete myelinating OLs), and one GalC plate (to purify the remaining PDGFRα-, MOG-, OLs). The adherent cells on the first PDGFRα, MOG, and GalC plates were washed to remove all antigen-negative nonadherent cells. The cells were then lysed while still attached to the panning plate with Qiagen RLT lysis buffer, and total RNA was purified. Purified OPCs were >95% NG2 positive and 0% MOG positive. Purified Myelin OLs were 100% MOG positive, >95% MBP positive, and 0% NG2 positive. Purified GalC OLs depleted of OPCs and Myelin OLs were <10% MOG positive and ~50% weakly NG2 positive, a reflection of their recent development as early OLs.; Data normalization and analysis: Raw image files were processed using Affymetrix GCOS and the MAS 5.0 algorithm. Intensity data was normalized per chip to a target intensity TGT value of 500, and expression data and absent/present calls for individual probe sets were determined. Gene expression values were normalized and modeled across arrays using the dChip software package with invariant-set normalization and a PM model. (www.dchip.org, Li and Wong, 2001). The 29 samples were grouped into 9 sample types: Astros P7-P8, Astros P17, Astros P17-gray matter (P17g), Neurons P7, Neurons P17, Neurons-endothelial cell depleted (P7n, P17n), OPCs, GalC-OLs, and MOG-OLs. Gene filtering was performed to select probe sets that were consistently expressed in at least one cell type, where consistently expressed was defined as being called present and having a MAS 5.0 intensity level greater than 200 in at least two-thirds of the samples in the cell type. We identified 20,932 of the 45,037 probe sets that were consistently expressed in at least one of the nine cell types. The Significance Analysis of Microarrays (SAM) method (Tusher et al., 2001) was used to determine genes that were significantly differentially expressed between different cell types (see Supplemental Table S2 for SAM cell type groupings). Clustering was performed using the hclust method with complete linkage in R. Expression values were transformed for clustering by computing a mean expression value for the gene using those samples in the corresponding SAM statistical analysis, and then subtracting the mean from expression intensities. In order to preserve the log2 scale of the data, unless otherwise indicated, no normalization by variance was performed. Plots were created using the gplots package in R. The Bioconductor software package (Gentleman et al., 2004) was used throughout the expression analyses. Functional analyses were performed through the use of Ingenuity Pathways Analysis (Ingenuity® Systems, www.ingenuity.com).
2007-12-30 | E-GEOD-9566 | biostudies-arrayexpress
Project description:Nodal/Activin signaling directs mesendoderm specification in early vertebrate embryogenesis. We have characterized transcriptional profiling of human embryonic stem cells and Activin-treated cells at different timepoints. In this dataset, we include the timecourse gene expression data obtained from hESC differentiation post Activin treatment, examining at day 0, 1, 3 and 5. Four biological replicates were used for day 0, three for day 1, three for day 3, and four for day 5. Cells were harvested and used for total RNA preparation using Trizol (Invitrogen). Gene expression was analyzed using GeneChip Human Exon 1.0 ST Array (Affymetrix).
2011-05-21 | E-GEOD-29421 | biostudies-arrayexpress
Project description:Gastric cancers account for the fourth most frequent cancer death worldwide. Although many differential gene expression profiles are reported for gastric cancers, their variation at the post-transcriptional level has not been provided yet. In this study, we compared the gene expressions of normal stomach vs. stomach cancer in an exon-wise manner and compared alternatively spliced transcripts. The RNA from normal and cancer tissues of gastric cancer patients were subjected to Exon 1.0 ST microarrays. Transcriptome analysis of RNAs from normal and cancer tissues of human stomach by exon array. We analyzed 30 pairs of normal-cancer stomach tissues using the Affymetrix Human Exon 1.0 ST platform. Array data was processed by the Affymetrix Exon Array Computational Tool.
2014-07-12 | E-GEOD-30727 | biostudies-arrayexpress
Project description:PU.1 is a key transcription factor for macrophage differentiation. Novel PU.1 target genes were identified by mRNA profiling of PU.1-deficient progenitor cells (PUER) before and after PU.1 activation. We used two different types of Affymetrix DNA-microarrays (430 2.0 arrays and ST 1.0 exon arrays) to characterize the global PU.1-regulated transcriptional program underlying the early processes of macrophage differentiation. Keywords: time course Uninduced and 24h 4-hydroxy-tamoxifen (OHT) induced PUER cells were cultured before RNA extraction and hybridization on Affymetrix Mouse Genome 430 2.0 and Mouse Exon ST 1.0 microarrays. Triplicates before (0h) and after (24h) induction of PU.1 were analyzed.
2008-10-11 | E-GEOD-13125 | biostudies-arrayexpress