The tumor suppressor p53 can induce various biological responses. Yet it is not clear whether it is p53 in vivo promoter selectivity that triggers different transcription programs leading to different outcomes. Our analysis of genome-wide chromatin occupancy by p53 using ChIP-seq (deposited in Sequence Read Archive database as SRP007261) revealed p53 default program, i.e. the pattern of major p53-bound sites that is similar upon p53 activation by nutlin3a, RITA or 5-FU in breast cancer cells, despite different biological outcomes triggered by these compounds. Parallel analysis of gene expression allowed identification of 280 previously unknown p53 target genes, including p53-repressed AURKA. The consensus p53 binding motif was present more frequently in p53-induced, than in repressed targets, indicating different mechanisms of gene activation versus repression. We identified several possible cofactors of p53, and found that STAT3 antagonised p53-mediated repression of a subset of genes, including AURKA. Finally, we showed that the expression of the novel p53 targets correlates with p53 status and survival in breast cancer patients.
Insights into p53 transcriptional function via genome-wide chromatin occupancy and gene expression analysis.
Cell line, Treatment
View SamplesThe Cohesin apparatus has a canonical role in sister chromatid cohesion. Heterozygous mutations in Nipped B-like (NIPBL), SMC1A, and SMC3 have been found in 60% of probands with Cornelia de Lange Syndrome (CdLS), a dominant multi-system genetic disorder with variable expression. We have performed a genome-wide transcription assessment as well as cohesin binding analysis using human lymphoblastoid cell lines (LCLs) from probands with CdLS and controls. Here, we report a unique profile of genes dysregulated in CdLS that correlates with different clinical presentations. Genome-wide analysis of cohesin binding demonstrates a preference for intergenic regions suggesting a cis-regulatory function mimicking that of an insulator. However, the binding sites are enriched within the promoter regions of the dysregulated genes and are significantly decreased in CdLS probands, indicating an alternative role of cohesin as a classic transcription factor. Cohesin also co-localizes with CTCF at the boundary elements affecting neighboring gene expression in CdLS probands. We propose that the CdLS phenotype is the result of dysregulated gene expression rather than defective sister chromatid cohesion. Phenotype specific expression profiles are also described.
Transcriptional dysregulation in NIPBL and cohesin mutant human cells.
Sex
View SamplesPurpose: The goal of this study is to identify host genes whose expression is perturbed in primary CD4+ T cells by histone deacetylase (HDAC) inhibitors (HDACi) SAHA and RMD, which have different potencies and specificities for various HDACs. The study aims to evaluate the effects of SAHA and RMD that may promote or inhibit reactivation of HIV provirus out of latency. Methods: Peripheral blood mononuclear cells were collected from 4 HIV-seronegative donors. CD4+ T cells were isolated and utilized to generate an in vitro model of latent HIV infection (model developed in the Spina laboratory and previously described in Spina et al., 2013). Mock-infected cells were cultured in parallel to evaluate effects of SAHA and RMD that may be dependent on the exposure of cells to virus. Following generation of the model, cells were treated with SAHA, RMD or their solvent dimethyl sulfoxide (DMSO) for 24 hours. Mock-infected cells were treated in parallel. The experiment had 4 biological replicates, 6 conditions for each, for a total of 24 samples. ERCC spikes (Thermo Fisher Scientific, Inc.) were added to cell lysates based on cell number in each sample (10 ul of 1:800 dilution per million cells). Mix 1 was used for DMSO- and mix 2 for SAHA- and RMD-treated cells. After all samples were collected, RNA was extracted and subjected to deep sequencing by Expression Analysis, Inc. Sequence reads that passed quality filters were mapped using Tophat (human genome) or Bowtie (ERCC spikes and HIV) and counted using HTSeq. ERCC spikes with the same concentration in mixes 1 and 2 were utilized to remove unwanted technical variation. Any human gene which did not achieve at least 1 count per million reads in at least 4 samples or any ERCC that did not achieve at least 5 reads in at least 4 samples was discarded. Differential gene expression analysis was performed using library EdgeR in Bioconductor R. National Center for Biotechnology Information (NCBI) HIV-1 Human Interaction Database was then searched for genes that have been implicated in controlling HIV latency. EdgeR output was used to extract expression information of the genes of interest from the NCBI database to identify genes implicated in HIV latency that were modulated by SAHA and RMD. The resulting lists were manually curated to verify relevance to HIV latency, using the Description column of the NCBI database, as well as available PubMed references. Results: Using a custom built data analysis pipeline, ~100 million reads per sample were mapped to the human genome (build hg38). After applying filtering criteria, 16058 human transcripts, 19 ERCC spikes transcripts, and HIV NL4-3 transcripts were identified with the Tophat/Bowtie and HTSeq workflow. Differential expression analysis was performed between SAHA or RMD-treated and DMSO-treated cells. In addition, differential modulation of gene expression by SAHA and RMD in the model of HIV latency and mock-infected cells was assessed using EdgeR. In mock-infected cells, SAHA upregulated 3,971 genes and downregulated 2,940 genes; RMD upregulated 5,068 genes and downregulated 4,050 genes. In the model of HIV latency, SAHA upregulated 3,498 genes and downregulated 2,904 genes; RMD upregulated 5,116 genes and downregulated 4,053 genes (FDR < 0.05). SAHA modulated 6, and RMD 11 genes differentially between mock-infected cells and the model of HIV latency. Following search of the NCBI HIV-1 Human Interaction Database, 27 genes upregulated and 29 downregulated in common between SAHA and RMD were found to be relevant to regulation of HIV latency; 31 were up- and 32 downregulated by RMD only; and 6 were up- and 2 were downregulated by SAHA only. Conclusions: This study demonstrates that SAHA and RMD, which have different potencies and specificities for HDACs, modulate a set of overlapping genes implicated in regulation of HIV latency. Some of these genes may be explored as additional host targets for improving the outcomes of “shock and kill” strategies. Overall design: Transcriptomic profiling of the in vitro model of HIV latency and mock-infected cells treated with SAHA, RMD or the solvent DMSO (N=4 donors) by deep sequencing at Expression Analysis, Inc.
Long non-coding RNAs and latent HIV - A search for novel targets for latency reversal.
Specimen part, Treatment, Subject
View SamplesNovel approaches were used to generate the DNA sequence information for the rhesus GeneChip (2005). The purpose of this experiment was to test its reliability and validity of the rhesus macaque GeneChip across different tissues and centers.
Intercenter reliability and validity of the rhesus macaque GeneChip.
Specimen part, Cell line
View SamplesWe obtained global measurements of decay and translation rates for mammalian mRNAs with alternative 3'' untranslated regions (3'' UTRs). Overall design: 1 3P-Seq sample from 3T3 cells and 1 3P-Seq sample from mouse ES cells; 2 2P-Seq steady state and 4 2P-Seq with actinomycin D; 6 polysome fraction 2P-Seq
3' UTR-isoform choice has limited influence on the stability and translational efficiency of most mRNAs in mouse fibroblasts.
Specimen part, Treatment, Subject
View SamplesThe primary goal of this study was to compare the performances of Rhesus Macaque Genome Array and Human Genome U133 Plus 2.0 Array with respect to the detection of differential expressions when rhesus macaque RNA extracts were labeled and hybridized.
Large scale analysis of positional effects of single-base mismatches on microarray gene expression data.
Specimen part, Cell line
View SamplesWe profiled genome-wide gene expression of 170 individual mid-gestation (embryonic day 11.5) whole mouse embryos derived from a 2-generation interspecies mouse cross and asked to what extent genetic variation drives four important parameters of regulatory architecture: allele-specific expression (ASE), imprinting, trans-regulatory effects, and maternal effect. The inbred strain C57BL/6J and wild-derived inbred strain CAST/EiJ were used in reciprocal crosses to generate F1 embryos. F1 progeny were backcrossed to C57BL/6J in reciprocal crosses to generate 154 N2 embryos. We employed a backcross design, in which N2 offspring have genotypically distinct parents, to enable comparison of gene expression for offspring from each side of the reciprocal cross. Our findings demonstrate that genetic variation contributes to widespread gene expression differences during mammalian embryogenesis. Overall design: Transcriptome analysis of E11.5 mouse embryos: 16 F1 embryos from reciprocally crossed C57BL/6J and CastEi/J parents; and 154 N2 embryos from reciprocal backcross of F1s to the C57BL/6J parent.
Constraint and divergence of global gene expression in the mammalian embryo.
No sample metadata fields
View SamplesDesign: Persistent latently infected CD4+ T cells represent a major obstacle to HIV eradication. Histone deacetylase inhibitors (HDACis) are a promising activation therapy in a shock and kill strategy. However, off-target effects of HDACis on host gene expression are poorly understood in primary cells of the immune system. We hypothesized that HDACi-modulated genes would be best identified with a dose response analysis. Methods: Resting primary CD4+ T cells were treated with increasing concentrations (0.34, 1, 3, or 10 M) of the HDACi, suberoylanilide hydroxamic acid (SAHA), for 24 hours and then subjected to microarray gene expression analysis. Genes with dose-correlated expression were identified with a likelihood ratio test using Isogene GX and a subset of these genes with a consistent trend of up or downregulation at each dose of SAHA were identified as dose-responsive. Histone modifications were characterized in promoter regions of the top 6 SAHA dose-responsive genes by RT-qPCR analysis of immunopreciptated chromatin (ChIP). Results: A large number of genes were shown to be up (N=657) or down (N=725) regulated by SAHA in a dose-responsive manner (FDR p-value < 0.05 and fold change |2|). Several of these genes (CTNNAL1, DPEP2, H1F0, IRGM, PHF15, and SELL) are potential in vivo biomarkers of SAHA activity. SAHA dose-responsive gene categories included transcription factors, HIV restriction factors, histone methyltransferases, and host proteins that interact with HIV proteins or the HIV LTR. Pathway analysis suggested net downregulation of T cell activation with increasing SAHA dose. Histone acetylation was not correlated with host expression, but plausible alternative mechanisms for SAHA-modulated expression were identified. Conclusions: Numerous host genes in CD4+ T cells are modulated by SAHA in a dose-responsive manner, including genes that may negatively influence HIV activation from latency. Our study suggests that SAHA influences gene expression through a confluence of several mechanisms, including histone acetylation, histone methylation, and altered expression and activity of transcription factors.
Dose-responsive gene expression in suberoylanilide hydroxamic acid-treated resting CD4+ T cells.
Specimen part, Subject
View SamplesIn mammals, extracellular miRNAs circulate in biofluids as stable entities that are secreted by normal and diseased tissues, and can enter cells and regulate gene expression. Drosophila melanogaster is a proven system for the study human diseases. They have an open circulatory system in which hemolymph (HL) circulates in direct contact with all internal organs, in a manner analogous to vertebrate blood plasma. Here we show using deep sequencing that Drosophila HL contains RNase resistant, circulating miRNAs (HL-miRNAs). Limited subsets of body tissue miRNAs (BT-miRNAs) accumulated in HL, suggesting they may be specifically released from cells or particularly stable in HL. Alternatively, they might arise from specific cells such as hemocytes, in intimate contact with HL. Young and old flies accumulated unique populations HL-miRNAs, suggesting their accumulation is responsive to the physiological status of the fly. These HL-miRNAs may function in flies similarly to the miRNAs circulating in mammalian biofluids. The discovery of these HL-miRNAs will provide a new venue for health and disease-related research in Drosophila. Overall design: Examination of mRNA levels in body tissues of young and old Drosophila melanogaster.
MicroRNAs Circulate in the Hemolymph of Drosophila and Accumulate Relative to Tissue microRNAs in an Age-Dependent Manner.
Sex, Age, Specimen part, Subject
View SamplesPurpose: Aim of the study is to identify changes in hepatic gene expression induced by either a 40kcal% coconut oil rich high fat diet (HFD), a 40kcal% soybean oil plus coconut oil high fat diet (SO-HFD) or a low fat vivarium chow diet (Viv). Methods: Livers from mice that had been fed one of the above mentioned diets for 35 weeks, were used to make cDNA libraries that were then sent for deep sequencing, using the Illumina TruSeq RNA. Result: Many genes involved in metabolism, lipid binding, transport and storage and many Cyp genes are dysregulated in the two high fat diets as compared to Viv HFDs in SO-HFD mice. Comparing the two HFDs shows more metabolism and disease related genes dysregulated in SO-HFD vs HFD. Conclusion: A diet high in soybean oil may be more detrimental to metabolic health than a diet high in saturated fats. Overall design: cDNA isolated from livers from mice fed HFD, SO-HFD or Viv for 35 weeks, were 50bp pair-ended sequenced in triplicate using Illumina TruSeq RNA Sample Prep v2 Kit.
Soybean Oil Is More Obesogenic and Diabetogenic than Coconut Oil and Fructose in Mouse: Potential Role for the Liver.
No sample metadata fields
View Samples