The hair of all mammals consists of terminally differentiated cells that undergo a specialized form of apoptosis called cornification. While DNA is destroyed during cornification, the extent to which RNA is lost is unknown. Here we find that multiple types of RNA are incompletely degraded after hair shaft formation in both mouse and human. Notably, mRNAs and short regulatory microRNAs (miRNAs) are stable in the hair as far as 10 cm from the scalp. To better characterize the post-apoptotic RNAs that escape degradation in the hair, we performed sequencing (RNA-seq) on RNA isolated from hair shafts pooled from several individuals. This hair shaft RNA library, which encompasses different hair types, genders, and populations, revealed 7,193 mRNAs, 449 miRNAs and thousands of unannotated transcripts that remain in the post-apoptotic hair. A comparison of the hair shaft RNA library to that of viable keratinocytes revealed surprisingly similar patterns of gene coverage and indicates that degradation of RNA is highly inefficient during apoptosis of hair lineages. The generation of a hair shaft RNA library could be used as months of accumulated transcriptional history useful for retrospective detection of disease, drug response and environmental exposure.
The post-apoptotic fate of RNAs identified through high-throughput sequencing of human hair.
No sample metadata fields
View SamplesThe effect of Tlr4P712H mutation (rendering TLR4 non-functional), or gut-sterilization by antbiotics, on the induction of tumorgenesis by CCl4 and diethylnitrosamine (DEN) was characterized. Affymetrix Mouse 430 2.0 gene expression measurements were used to characterize the transcriptomic basis of the effects of the above treatments and genotypes on tumorgenesis.
Promotion of hepatocellular carcinoma by the intestinal microbiota and TLR4.
Sex, Age, Specimen part
View SamplesGene expression of hepatocyt-specific knockout of Pten and of Pten and Tgfbr2 in mice
Epithelial Transforming Growth Factor-β Signaling Does Not Contribute to Liver Fibrosis but Protects Mice From Cholangiocarcinoma.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrated epigenetics of human breast cancer: synoptic investigation of targeted genes, microRNAs and proteins upon demethylation treatment.
Treatment
View SamplesThe contribution of aberrant DNA methylation and the downstream effects in tumorogenesis through silencing of tumor suppressor genes (TSGs) and microRNAs has been investigated. Since these epigenetic alterations can be reversed, we investigated the effects of the epigenetic therapy in breast cancer cell lines.
Integrated epigenetics of human breast cancer: synoptic investigation of targeted genes, microRNAs and proteins upon demethylation treatment.
Treatment
View SamplesRNA expression microarray analysis of prospermatogonia in 15 day post-conceptus (dpc) fetuses, a stage when they are undergoing rapid de novo DNA methylation. For comparison, we also analysed 15 dpc pachytene oogonia, 15 dpc female and male gonadal somatic cells, and adult pachytene spermatocytes.
RNA expression microarray analysis in mouse prospermatogonia: identification of candidate epigenetic modifiers.
Sex, Specimen part
View SamplesSOX9 is a transcriptional activator required for chondrogenesis, and SOX5 and SOX6 are closely related DNA-binding proteins that critically enhance its function. We used RNA-seq to charatierize a rat chondrosarcoma (RCS) cells as a faithful model for proliferating/early prehypertrophic growth plate chondrocytes and ChIP-seq to gain novel insights into the full spectrum of the target genes and modes of action of this chondrogenic trio. Overall design: RNAs were isolated from three bioogical replicatse of rat chondrosarcoma (RCS) cells and rib samples for RNA-seq experiments.
The transcription factors SOX9 and SOX5/SOX6 cooperate genome-wide through super-enhancers to drive chondrogenesis.
No sample metadata fields
View SamplesCD74, a Type II membrane glycoprotein and MHC class II chaperone (Ii), is normally expressed by cells associated with the immune system. CD74 also forms heterodimers with CD44 to generate receptors to macrophage migration inhibitory factor (MIF), a proinflammatory cytokine. Following targeted Cre-mediated deletion of Ikk in IkkDeltaHep mice (a strain highly susceptible to chemically-induced hepatotoxicity and hepatocarcinogenesis), CD74 is abundantly expressed by hepatocytes throughout liver acini (as detected by specific Western blots and immunohistochemical stains); it is not observed in either control IkkF/F hepatocytes or embryonic fibroblasts from Ikk-/- mice. Constitutive CD74 expression in IkkDeltaHep hepatocytes is also accompanied by significantly augmented expression of CD44 and genes associated with antigen processing and host defense. These observations suggest that IkkDeltaHep hepatocytes might directly respond to MIF signaling, accounting partly for the enhanced susceptibility of IkkDeltaHep mice to hepatotoxins and hepatocarcinogens, and also might exhibit unusual immunological properties including antigen presentation.
Targeted deletion of hepatocyte Ikkbeta confers growth advantages.
Specimen part
View SamplesThe molecular processes underlying human milk production and the effects of mastitic infection are largely unknown because of limitations in obtaining tissue samples. Determination of gene expression in normal lactating women would be a significant step towards understanding why some women display poor lactation outcomes. Here we demonstrate the utility of RNA obtained directly from human milk cells to detect mammary epithelial cell (MEC)-specific gene expression. Milk cell RNA was collected from 5 time points (24 hours pre-partum during the colostrum period, mid lactation, two involution, and during a bout of mastitis) in addition to an involution series comprising three time points. Gene expression profiles were determined by use of human Affymetrix arrays. Milk cells collected during milk production showed that the most highly expressed genes were involved in milk synthesis (eg. CEL, OLAH, FOLR1, BTN1A1, ARG2), while milk cells collected during involution showed a significant down regulation of milk synthesis genes and activation of involution associated genes (eg. STAT3, NF-kB, IRF5, IRF7). Milk cells collected during mastitic infection revealed regulation of a unique set of genes specific to this disease state, whilst maintaining regulation of milk synthesis genes. Use of conventional epithelial cell markers was used to determine the population of MECs within each sample. This paper is the first to describe the milk cell transcriptome across the human lactation cycle and during mastitic infection, providing valuable insight into gene expression of the human mammary gland.
Analysis of human breast milk cells: gene expression profiles during pregnancy, lactation, involution, and mastitic infection.
Specimen part
View SamplesThe Early Growth Response (Egr) family of transcription factors consists of 4 members (Egr1-4) that are expressed in a wide variety of cell types. A large body of evidence point to a role for Egr transcription factors in growth, survival, and differentiation. A major unanswered question is whether Egr transcription factors serve similar functions in diverse cell types by activating a common set of target genes. Signal transduction cascades in neurons and lymphocytes show striking parallels. Activation of either cell type activates the Ras-MAPK pathway and, in parallel, leads to increases in intracellular calcium stimulating the calcineurin-NFAT pathway. In both cell types, the strength of the activation signal affects the cellular outcomes and very strong stimuli lead to cell death. Notably both these pathways converge on the induction of Egr genes. We believe that downstream targets of Egr transcription factors in lymphocytes may also be activated by Egr factors in activated neurons. There is precedence for common target gene activation in these two cell types: apoptosis in both activated T cells and methamphetamine stimulated neurons occurs via FasL induction by NFAT transcription factors. We propose to use developing T lymphocytes (thymocytes) as a model system for discovery of Egr-dependent target genes for several reasons. First, we have observed a prominent survival defect in thymocytes from mice deficient in both Egr1 and Egr3 (1/3 DKO) and a partial differention block in the immature double negative (DN) stage. In addition, thymocytes are an easily manipulatable cell type, and the DN subpopulation affected in 1/3 DKO mice can be isolated to very high purity. We anticipate that 1/3 DKO thymocytes will provide an excellent experimental system that will provide insight into Egr-dependent transcription in neuronal development, activation, and death.
Redundant role for early growth response transcriptional regulators in thymocyte differentiation and survival.
No sample metadata fields
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