Deprivation of peripheral nerve input by cochlear removal in young mice results in dramatic neuron death in the cochlear nucleus (CN). The same manipulation in older mice does not result in significant loss. The molecular basis of this critical period of vulnerability remains largely unknown. Here we identified genes regulated at early time points after cochlear removal at ages when neurons are vulnerable (postnatal day (P)7) or invulnerable (P21) to this challenge. Afferent deprivation regulated very different sets of genes at P7 and P21. These genes showed a variety of functions at both ages, but surprisingly there was no net increase in pro-apoptotic genes at P7. A large set of upregulated immune-related genes was identified at P21.
Afferent deprivation elicits a transcriptional response associated with neuronal survival after a critical period in the mouse cochlear nucleus.
No sample metadata fields
View SamplesWe analyzed whether cochlear removal-induced transcriptional changes in the cochlear nucleus (CN) were due to loss of electrical activity in the 8th nerve. Pharmacological activity blockade of the auditory nerve for 24 h resulted in similar expression changes for only a subset of genes. Thus, an additional factor not dependent on action potential-mediated signaling must also regulate transcriptional responses to deafferentation in the CN.
Afferent deprivation elicits a transcriptional response associated with neuronal survival after a critical period in the mouse cochlear nucleus.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Research resource: Genome-wide profiling of progesterone receptor binding in the mouse uterus.
Sex, Age, Specimen part, Treatment
View SamplesProgesterone (P4) signaling through its nuclear transcription factor, the progesterone receptor (PR), is essential for normal uterine function. Although deregulation of PR mediated signaling is known to underscore uterine dysfunction and a number of endometrial pathologies, the early molecular mechanisms of this deregulation are unclear. To address this issue, we have defined the genome-wide PR and GATA2 cistrome in the murine uterus using chromatin immunoprecipitation followed by massively parallel sequencing (ChIP-seq). In uteri of ovariectomized mice, we identified 6367 PR binding sites in the absence of P4 ligand; however, this number increased at nearly three fold (18,432) following acute P4 exposure. Sequence analysis revealed that approximately 73% of these binding sites contain a progesterone response element (PRE) or a half-site motif recognized by the PR. Many previously identified P4 target genes known to regulate uterine function were found to contain PR binding sites, confirming the validity of our methodology. In addition we identified 46,183 GATA2 binding sites in P4 treatment conditions with 7,954 binding sites overlapping that of the PR.
Research resource: Genome-wide profiling of progesterone receptor binding in the mouse uterus.
Sex, Age, Specimen part
View SamplesBackground. Most colorectal cancers (CRC) arise in a progression through adenoma to carcinoma phenotypes as a consequence of altered genetic information. Clinical progression of CRC may occur in parallel with distinctive signaling alterations. We designed multidirectional analyses integrating microarray-based data with biostatistics and bioinformatics to elucidate the signaling and metabolic alterations underlying CRC development in the adenoma-carcinoma sequence. Methodology/Principal Findings. Studies were performed on normal mucosa, adenoma, and CRC samples obtained during surgery or colonoscopy. Collections of cryostat sections prepared from the tissue samples were evaluated by a pathologist to control the relative cell type content. RNA was isolated from 105 macro- and 40 microdissected specimens. The measurements were done using Affymetrix GeneChip HG-U133plus2, and probe set data were generated using two normalization algorithms: MAS5 and GCRMA with LVS. The data were evaluated using pair-wise comparisons and data decomposition into SVD modes. The method selected for the functional analysis used the Kolmogorov-Smirnov test. Based on a consensus of the results obtained by two tissue handling procedures, two normalization algorithms, and two probe set sorting criteria, we identified six KEGG signaling and metabolic pathways (cell cycle, DNA replication, p53 signaling pathway, purine metabolism, pyrimidine metabolism, and RNA polymerase) that are significantly altered in both macro- and microdissected tumor samples compared to normal colon. On the other hand, pathways altered between benign and malignant tumors were identified only in the macrodissected tissues. Conclusion/Significance. Multidirectional analyses of microarray data allow the identification of essential signaling alterations underlying CRC development. Although the proposed strategy is computationally complex and laborintensive, it may reduce the number of false results.
Modeling oncogenic signaling in colon tumors by multidirectional analyses of microarray data directed for maximization of analytical reliability.
Sex, Age, Specimen part
View SamplesBarrett's esophagus is characterized by the replacement of squamous epithelium with specialized intestinal metaplastic mucosa. The exact mechanisms of initiation and development of Barrett's metaplasia remain unknown, but a hypothesis of successful adaptation against noxious reflux components has been proposed. To search for the repertoire of adaptation mechanisms of Barrett's metaplasia, we employed high-throughput functional genomic and proteomic methods that defined the molecular background of metaplastic mucosa resistance to reflux. Transcriptional profiling was established for 23 pairs of esophageal squamous epithelium and Barrett's metaplasia tissue samples using Affymetrix U133A 2.0 GeneChips and validated by quantitative real-time polymerase chain reaction. Differences in protein composition were assessed by electrophoretic and mass-spectrometry-based methods. Among 2,822 genes differentially expressed between Barrett's metaplasia and squamous epithelium, we observed significantly overexpressed metaplastic mucosa genes that encode cytokines and growth factors, constituents of extracellular matrix, basement membrane and tight junctions, and proteins involved in prostaglandin and phosphoinositol metabolism, nitric oxide production, and bioenergetics. Their expression likely reflects defense and repair responses of metaplastic mucosa, whereas overexpression of genes encoding heat shock proteins and several protein kinases in squamous epithelium may reflect lower resistance of normal esophageal epithelium than Barrett's metaplasia to reflux components. Despite the methodological and interpretative difficulties in data analyses discussed in this paper, our studies confirm that Barrett's metaplasia may be regarded as a specific microevolution allowing for accumulation of mucosal morphological and physiological changes that better protect against reflux injury.
Molecular defense mechanisms of Barrett's metaplasia estimated by an integrative genomics.
Sex, Age
View SamplesIn order to gain a better understanding of Ihh action during embryo implantation, we constitutively activated Smo in the murine uterus using the PRcre mouse model (PRcre/+SmoM2+; SmoM2). Female SmoM2 mice were infertile. They exhibited normal serum progesterone levels and normal ovulation, but ova failed to be fertilized in vivo and the uterus failed to undergo the artificially induced decidual response. SmoM2 mice exhibited uterine hypertrophy. The endometrium had a reduced number of uterine glands and the endometrial stroma lost its normal morphologic characteristics. Microarray analysis of 3 month old SmoM2 uteri demonstrated a chondrocytic signature and confirmed that constitutive activation of SmoM2 increased extracellular matrix production. Thus, constitutive activation of Smo in the mouse uterus alters the extracellular matrix which interferes with early pregnancy.
Constitutive activation of smoothened leads to female infertility and altered uterine differentiation in the mouse.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A Gata2-Dependent Transcription Network Regulates Uterine Progesterone Responsiveness and Endometrial Function.
Sex, Age, Specimen part, Treatment
View SamplesGata2 dependent genes in mouse uteri were identified by the conditional ablation of Gata2 using the (PR-cre) mouse upon acute progesterone administration.
A Gata2-Dependent Transcription Network Regulates Uterine Progesterone Responsiveness and Endometrial Function.
Sex, Age, Specimen part
View SamplesThe role of Gata2 in regulating uterine function including fertility, implantation, decidualization and P4 signaling in the mouse was investigated by the conditional ablation of Gata2 in the uterus using the (PR-cre) mouse and ChIP-seq for in vivo GATA2 binding sites in the murine uterus upon acute P4 administration.
A Gata2-Dependent Transcription Network Regulates Uterine Progesterone Responsiveness and Endometrial Function.
Sex, Age, Specimen part
View Samples