gene expression database and algorithm to define cell expression modules
Identifying gene expression modules that define human cell fates.
Specimen part
View SamplesWork previously published by our group has demonstrated that T cells from patients with chronic lymphocytic leukaemia (CLL) show differentially regulated genes compared with healthy T cells. This study was initiated to examine if these gene expression changes were unique to CLL T cells or common to an alternative leukaemia, acute myeloid leukaemia (AML).
Peripheral blood T cells in acute myeloid leukemia (AML) patients at diagnosis have abnormal phenotype and genotype and form defective immune synapses with AML blasts.
Sex, Age
View SamplesRNAseq profiling of 10 time points during germination in Arabidopsis, from freshly harvested seed, through mature seed, stratification, germination and to post-germination. Overall design: Total RNA was extracted from Arabidopsis seeds at 10 time points during germination in triplicate. The time points were: freshly harvested seed (H), seeds following 15 days of ripening (0 h), seeds after; 1 h of stratification (1 h S), 12 h of stratification (12 h S), 48 h of stratification (48 h S), followed by seed collected 1 hour into the light (1 h SL), 6 hours into the light (6 h SL), 12 hours into the light (12 h SL), 24 hours into the light (24 h SL) and 48 hours into the light (48 h SL).
Extensive transcriptomic and epigenomic remodelling occurs during Arabidopsis thaliana germination.
Specimen part, Subject, Time
View SamplesWe developed an affinity purification approach to isolate tagged nuclei in mice (similar to INTACT; [Deal R.B. and Henikoff S. A simple method for gene expression and chromatin profiling of individual cell types within a tissue. Dev. Cell 18,1030-1040. (2010)]) and used it to characterize genome-wide patterns of transcription, DNA methylation, and chromatin accessibility in 3 major neuron classes of the neocortex (excitatory pyramidal neurons, parvalbumin (PV)-positive GABAergic interneurons, and vasoactive intestinal peptide (VIP)-positive GABAergic interneurons). By combining cell purification and integrative analysis, our findings relate the phenotypic and functional complexity of neocortical neurons to their underlying transcriptional and epigenetic diversity. Overall design: RNA-seq, MethylC-seq, ATAC-seq, and ChIP-seq for histone modifications using INTACT-purified nuclei from the mouse neocortex
Epigenomic Signatures of Neuronal Diversity in the Mammalian Brain.
No sample metadata fields
View SamplesWhile genetic mutation is a hallmark of cancer, many cancers also acquire epigenetic alterations during tumorigenesis including aberrant DNA hypermethylation of tumor suppressors as well as changes in chromatin modifications as caused by genetic mutations of the chromatin-modifying machinery. However, the extent of epigenetic alterations in cancer cells has not been fully characterized. Here, we describe the first complete methylome maps at single nucleotide resolution of a low-passage breast cancer cell line and primary human mammary epithelial cells. We find widespread DNA hypomethylation in the cancer cell, primarily at partially methylated domains (PMDs) in normal breast cells. Unexpectedly, genes within these regions are largely silenced in cancer cells. The loss of DNA methylation in these regions is accompanied by formation of repressive chromatin, with a significant fraction displaying allelic DNA methylation where one allele is DNA methylated while the other allele is occupied by histone modifications H3K9me3 or H3K27me3. Our results show a mutually exclusive and complementary relationship between DNA methylation and H3K9me3 or H3K27me3. These results suggest that global DNA hypomethylation in breast cancer is tightly linked to the formation of repressive chromatin domains and gene silencing, thus identifying a potential epigenetic pathway for gene regulation in cancer cells and suggesting a possible new approach toward the development of cancer therapeutics. Overall design: mRNA-Seq of polyA-selected RNA from breast cancer HCC1954 and normal breast HMEC. 36 cycles of sequencing on Illumina platform.
Global DNA hypomethylation coupled to repressive chromatin domain formation and gene silencing in breast cancer.
No sample metadata fields
View SamplesBackground. T cells in the thymus undergo opposing positive and negative selection processes so that the only T cells entering circulation are those bearing a T cell receptor (TCR) with a low affinity for self. The mechanism differentiating negative from positive selection is poorly understood, despite the fact that inherited defects in negative selection underlie organ-specific autoimmune disease in AIRE-deficient people and the non obese diabetic (NOD) mouse strain. Results. Here we use homogeneous populations of T cells undergoing either positive or negative selection in vivo together with genome-wide transcription profiling on microarrays to identify the gene expression differences underlying negative selection to an Aire-dependent organ-specific antigen, including the upregulation of a genomic cluster in the cytogenetic band 2F. Analysis of defective negative selection in the autoimmune-prone NOD strain demonstrates a global impairment in the induction of the negative selection response gene set, but little difference in positive selection response genes. Combining expression differences with genetic linkage data we identify differentially expressed candidate genes including Bim, Bnip3, Smox, Pdrg1, Id1, Pdcd1, Ly6c, Pdia3, Trim30 and Trim12. Conclusions. The data provide a molecular map of the negative selection response in vivo, and by analysis of deviations from this pathway in the autoimmune susceptible NOD strain, suggest that susceptibility arises from small expression differences in genes acting at multiple points in the pathway between the TCR and cell death.
Impairment of organ-specific T cell negative selection by diabetes susceptibility genes: genomic analysis by mRNA profiling.
No sample metadata fields
View SamplesMice lacking the beta 2 subunit (Chrnb2) of the neuronal nicotinic acetylcholine receptor display altered retinal waves and disorganized projections of the retinal ganglion cells to the lateral geniculate nucleus (LGN). mRNA populations from retinas and LGN from Chrnb2-/-and wild type (C57BL/6J) mice were compared at 4 days postnatal, when RGC segregation to the LGN begins in WT mice. Retinal mRNAs were also compared at adulthood.
Mouse mutants for the nicotinic acetylcholine receptor ß2 subunit display changes in cell adhesion and neurodegeneration response genes.
Sex, Specimen part
View SamplesFollicular lymphoma (FL) is genetically characterized by the presence of the t(14;18)(q32;q21) chromosomal translocation in approximately 90% of cases. In contrast to FL carrying the t(14;18), their t(14;18)-negative counterparts are less well studied regarding their immunohistochemical, genetic, molecular and clinical features. Within a previously published series of 184 FL grade 1-3A with available gene expression data, we identified 17 FL lacking the t(14;18). Comparative genomic hybridization and high resolution SNP array profiling demonstrated that gains/amplifications of the BCL2 gene locus in 18q were restricted to the t(14;18)-positive FL subgroup. A comparison of gene expression profiles revealed an enrichment of germinal center B-cell associated signatures in t(14;18)-positive FL, whereas activated B-cell like, NFB, proliferation and bystander cell signatures were enriched in t(14;18)-negative FL. These findings were confirmed by immunohistochemistry in an independent validation series of 84 FL, in which 32% of t(14;18)-negative FL showed weak or absent CD10 expression and 91% an increased Ki67 proliferation rate. Although overall survival did not differ between FL with and without t(14;18), our findings suggest distinct molecular features of t(14;18)-negative FL.
Follicular lymphomas with and without translocation t(14;18) differ in gene expression profiles and genetic alterations.
Specimen part, Disease, Disease stage, Subject
View SamplesHydrogen peroxide is known to promote skin keratinocyte migration, although the mechanism of action is unclear. In an attempt to identify signaling pathways regulated by hydrogen peroxide in the skin, 3 day post fertilized (dpf) zebrafish larvae (nacre strain) were treated with 3mM hydrogen peroxide for 2 hours and subjected to RNA-seq analyses. Pools of about 1000 embryos for each of three biological replicates were derived from 5 independent mating pairs and raised to larval stages until 3 dpf. All larvae were subsequently homogenized in Trizol and total RNA was extracted using a chloroform extraction protocol treated with DNAse. Messenger RNA (mRNA) was subsequently purified from total RNA using biotin-tagged poly dT oligonucleotides and streptavidin-coated magnetic beads, followed by quality control using an Agilent Technologies 2100 Bioanalyzer (values >7 were used for sequencing). The poly(A)-tailed mRNA samples were fragmented and double-stranded cDNA generated by random priming for deep sequencing studies. Overall design: 6 samples total were analyzed. 3 untreated, and 3 hydrogen peroxide treated (3mM, 2hr)
Comparative transcriptomic profiling of hydrogen peroxide signaling networks in zebrafish and human keratinocytes: Implications toward conservation, migration and wound healing.
No sample metadata fields
View SamplesBackground: Cystic fibrosis (CF) is caused by mutations in the CFTR gene that impair function of this cAMP-regulated Cl- channel. In the small intestine, loss of CFTR function creates a dehydrated, acidic luminal environment which is believed to cause an accumulation of mucus, a phenotype characteristic of CF. CF mice have an innate immune response and impaired intestinal transit as well. We investigated whether lubiprostone, which activates the CLC2 Cl- channel, would improve the CF intestinal phenotype.
Lubiprostone ameliorates the cystic fibrosis mouse intestinal phenotype.
Specimen part, Treatment
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