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GSE4866
Mus musculus
10 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Mitochondrial DNA (mtDNA) mutations may contribute to aging and age-related disorders. Previously, we created mice expressing a proofreading-deficient version of the mtDNA polymerase gamma (Polg) which accumulate age-related mtDNA mutations and display premature aging. Here we performed microarray gene expression profiling to identify mtDNA mutation-responsive genes in the cochlea of aged mitochondrial mutator mice. Age-related accumulation of mtDNA mutations was associated with transcriptional alternations consistent with reduced inner ear function, mitochondrial dysfunction, neurodegeneration, and reduced cell structural modulation. Hearing assessment and histopathological results confirmed that aged PolgD257A/D257A (D257A) mice exhibited moderate hearing loss and severe cochlear degenerations. Age-related accumulation of mtDNA mutations also resulted in alternations in gene expression consistent with induction of apoptosis, proteolysis, stress response, and reduced DNA repair. TUNEL (Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling) assay confirmed that the cochleae from aged D257A mice showed significantly more TUNEL positive cells compared to wild-type (WT) mice. The levels of cleaved caspase-3 were also found to increase in the cochleae of aged D257A mice. These observations provide evidence that age-related accumulation of mtDNA mutations is associated with apoptotic cell death in aged cochlea. Our results provide the first global view of molecular events associated with mtDNA mutations in postmitotic tissue, and suggest that apoptosis is the major mechanism of mtDNA mediated cell death in the development of age-related hearing disorder.
Publication Title
The role of mtDNA mutations in the pathogenesis of age-related hearing loss in mice carrying a mutator DNA polymerase gamma.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
To identify factors involved in OPC senescence, we compared gene expressions between OPC-CG4, OPC-FCS and OPC-Rev.
Publication Title
Esophageal cancer-related gene 4 is a secreted inducer of cell senescence expressed by aged CNS precursor cells.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 226 Downloadable Samples
NextSeq 500
Description
Molecular heterogeneity among spiral ganglion neurons (SGNs) in the mouse cochlea was investigated in two genetic backgrounds: 1) wildtype, 2) Vglut3-/-, which lack inner hair cell-driven glutamatergic activation of SGNs. Overall design: Individual spiral-ganglion neurons expressing the fluorescent reporter tdTomato were dissociated and manually placed into PCR tubes; single-cell libraries were made by the Smart-seq2 approach; sequencing was done using the NextSeq platform (Illumina) at an average read depth of 4.5 million; bioinformatic analysis was conducted in R. Genotypes: bhlhb5::cre/+; Ai14/+ (wildtype) and bhlhb5::cre/+;Ai14/+; Vglut3-/- (Vglut3-/-). Age: P25-P27
Publication Title
Sensory Neuron Diversity in the Inner Ear Is Shaped by Activity.
Sample Metadata Fields
Subject
View Samples- Homo sapiens
- 20 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Chronic lymphocytic leukemia (CLL) is a biologically heterogeneous illness with a variable clinical course. Loss of chromosomal material on chromosome 13 at cytoband 13q14 is the most frequent genetic abnormality in CLL, but the molecular aberrations underlying del13q14 in CLL remain incompletely characterized. We analyzed 171 CLL cases for LOH and sub-chromosomal copy loss on chromosome 13 in DNA from FACS-sorted CD19+ cells and paired buccal cells using the Affymetrix XbaI 50K SNP-array platform. The resulting high-resolution genomic maps, together with array-based measurements of expression levels of RNA in CLL cases with and without del13q14 and Q-PCR-based expression analysis of selected genes support the following conclusions: i) del13q14 is heterogeneous and composed of multiple subtypes with deletion of Rb or the miR15a/16 loci serving as anatomic landmarks, respectively ii) del13q14 type Ia deletions are relatively uniform in length and extend from breakpoints close to the miR15a/16 cluster to a newly identified telomeric breakpoint cluster at ~50.2-50.5 Mb physical position iii) LATS2 RNA levels are ~2.6-2.8-fold lower in cases with del13q14 type I that do not delete Rb as opposed to all other CLL cases and iv) ~15% of CLL cases display marked reductions in miR15a/16 expression often but not invariably associated with bi-allelic miR15a/16 loss. This data should aid future investigations into biological differences imparted on CLL by different del13q14 subtypes including investigations into LATS2 as one of the genes found deregulated as part of del13q14.
Publication Title
Integrated genomic profiling of chronic lymphocytic leukemia identifies subtypes of deletion 13q14.
Sample Metadata Fields
No sample metadata fields
View Samples- Pseudomonas aeruginosa
- 6 Downloadable Samples
- Ion Torrent Proton
Description
The PA0336 protein from Pseudomonas aeruginosa belongs to the family of widely distributed Nudix pyrophosphohydrolases which catalyze the hydrolysis of pyrophosphate bonds in a variety of nucleoside diphosphate derivatives. The amino acid sequence of the PA0336 protein is highly similar to that of the RppH Nudix RNA pyrophosphohydrolase from E. coli which removes pyrophosphate from 5'-end of triphosphorylated RNA transcripts. Trans-complementation experiments showed that the P. aeruginosa enzyme can functionally substitute for RppH in E. coli cells indicating that, similarly to RppH, the Pseudomonas hydrolase mediates RNA turnover in vivo. In order to elucidate the biological significance of the PA0336 protein in Pseudomonas cells, a PA0336 mutant strain was constructed. The mutated strain considerably increased level of the virulence factor pyocyanin compared to wild type, suggesting that PA0336 could be involved in down-regulation of P. aeruginosa pathogenicity. This phenotype was reversed by complementation with the wild type, but not catalytically inactive PA0336, indicating that the catalytic activity was indispensable for its biological function. To study the role of PA0336 further, transcriptomes of the PA0336 mutant and the wild type strain were compared using RNA sequencing. The cellular level of a number of transcripts was affected by the lack of PA0336. We focused our attention on pathogenesis-related genes. Up-regulated in the PA0336 mutant were transcripts coding for, i. a., proteins involved in the regulation and/or production of pyocyanin, biofim-associated alginates and exotoxins. The results from the global analysis were verified by determining the cellular level of chosen transcripts by quantitative RT-PCR method. Pathogenesis tests in Caenorhabditis elegans showed that the PA0336 mutant of P. aeruginosa was significantly more virulent than the parental strain, confirming further that the P. aeruginosa RNA pyrophosphohydrolase PA0336 modulates bacterial pathogenesis by down-regulating production of virulence factors. Overall design: Study comparing RNA expression of P. aeruginosa PA0336 mutant strain with wild type reference, both in biological triplicates, by RNA-seq performed on Ion Torrent Proton platform
Publication Title
Nudix-type RNA pyrophosphohydrolase provides homeostasis of virulence factor pyocyanin and functions as a global regulator in Pseudomonas aeruginosa.
Sample Metadata Fields
Cell line, Subject
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Gene 2.0 ST Array (hugene20st)
Description
We previously established long-term 3D organoid culture systems for several murine tissues (intestine, stomach, pancreas and liver) as well as human intestine and pancreas. Here, we describe culture conditions to generate long-term 3D culture from human gastric stem cells. The technology can be applied to study the epithelial response to infection with Helicobacter pylori. Human gastric cultures can expand indefinitely in 3D Matrigel. Cultures can be generated from normal tissue, from single sorted stem cells, or from tumor tissue. Organoids maintain many characteristics of the respective tissue in terms of histology, marker expression and euploidy. Organoids from normal tissue express markers of four lineages of the stomach and self-organize in gland and pit-domains. They can be directed to specifically express either lineages of the gastric gland, or the gastric pit by addition of Nicotinamide and withdrawal of Wnt. While gastric pit lineages react marginally to bacterial infection, gastric gland lineages mount a strong inflammatory response. The gastric culture system provides a unique tool to study gastric pathologies.
Publication Title
In vitro expansion of human gastric epithelial stem cells and their responses to bacterial infection.
Sample Metadata Fields
Sex, Age, Specimen part, Treatment
View Samples- Homo sapiens
- 99 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The introduction of microarray techniques to cancer research brought great expectations for finding biomarkers that would improve patients treatment; however, the results of such studies are poorly reproducible and critical analyses of these methods are rare. In this study, we examined global gene expression in 97 ovarian cancer samples. Also, validation of results by quantitative RT-PCR was performed on 30 additional ovarian cancer samples. We carried out a number of systematic analyses in relation to several defined clinicopathological features. The main goal of our study was to delineate the molecular background of ovarian cancer chemoresistance and find biomarkers suitable for prediction of patients prognosis. We found that histological tumor type was the major source of variability in genes expression, except for serous and undifferentiated tumors that showed nearly identical profiles. Analysis of clinical endpoints [tumor response to chemotherapy, overall survival, disease-free survival (DFS)] brought results that were not confirmed by validation either on the same group or on the independent group of patients. CLASP1 was the only gene that was found to be important for DFS in the independent group, whereas in the preceding experiments it showed associations with other clinical endpoints and with BRCA1 gene mutation; thus, it may be worthy of further testing. Our results confirm that histological tumor type may be a strong confounding factor and we conclude that gene expression studies of ovarian carcinomas should be performed on histologically homogeneous groups. Among the reasons of poor reproducibility of statistical results may be the fact that despite relatively large patients group, in some analyses one has to compare small and unequal classes of samples. In addition, arbitrarily performed division of samples into classes compared may not always reflect their true biological diversity. And finally, we think that clinical endpoints of the tumor probably depend on subtle changes in many and, possibly, alternative molecular pathways, and such changes may be difficult to demonstrate.
Publication Title
Gene expression analysis in ovarian cancer - faults and hints from DNA microarray study.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 19 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Purpose: The chromosomal deletion 11q affects biology and clinical outcome in CLL but del11q-deregulated genes remain incompletely characterized.
Publication Title
A pathobiological role of the insulin receptor in chronic lymphocytic leukemia.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 61 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
FITFATTWIN study identified from the FinnTwin16 Cohort, which is a population based, longitudinal study of Finnish twins born between October 1974 and December 1979. The participants had no chronic disease affecting the ability to exercise, no acute disease, and no drug or alcohol abuse.
Publication Title
iGEMS: an integrated model for identification of alternative exon usage events.
Sample Metadata Fields
Age, Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
- Affymetrix Mouse Gene 1.1 ST Array (mogene11st)
Description
Multipotent stem cells and their lineage-restricted progeny drive nephron formation within the developing kidney. Validated markers of these early stem/progenitor populations are essential for deciphering their in vivo function and for evaluating their clinical potential for treating adult kidney disease. Here, we document expression of the adult stem cell marker Lgr5 in the developing kidney and assess the stem/progenitor identity of Lgr5+ve cells via in vivo lineage tracing. The appearance and localization of Lgr5+ve cells coincided with that of the S-shaped body around E14. Lgr5 expression remained restricted to cell clusters within developing nephrons in the cortex until P7, when expression was permanently silenced. In vivo lineage tracing identified Lgr5 as a marker of a novel progenitor population within nascent nephrons dedicated to generating the thick ascending limb of Henle's loop and distal convoluted tubule. The Lgr5 surface marker and experimental models described here will be invaluable for deciphering the contribution of early nephron stem cells to developmental defects and for isolating human nephron progenitors as a prerequisite to evaluating their therapeutic potential.
Publication Title
Lgr5(+ve) stem/progenitor cells contribute to nephron formation during kidney development.
Sample Metadata Fields
Specimen part
View Samples