We demonstrate for the first time that the extracellular matrix glycoprotein Tenascin-C regulates the expression of key patterning genes during late embryonic spinal cord development, leading to a timely maturation of gliogenic neural precursor cells. We first show that Tenascin-C is expressed by gliogenic neural precursor cells during late embryonic development. The loss of Tenascin-C leads to a sustained generation and delayed migration of Fibroblast growth factor receptor 3 expressing immature astrocytes in vivo. Furthermore, we could demonstrate an upregulation of Nk2 transcription factor related locus 2 (Nkx2.2) and its downstream target Sulfatase 1 in vivo. A dorsal expansion of Nkx2.2-positive cells within the ventral spinal cord indicates a potential progenitor cell domain shift. Moreover, Sulfatase 1 is known to regulate growth factor signalling by cleaving sulphate residues from heparan sulphate proteoglycans. Consistent with this possibility we observed changes in both Fibroblast growth factor 2 and Epidermal growth factor responsiveness of spinal cord neural precursor cells. Taken together our data clearly show that Tenascin-C promotes the astroglial lineage progression during spinal cord development.
The extracellular matrix molecule tenascin C modulates expression levels and territories of key patterning genes during spinal cord astrocyte specification.
Specimen part
View SamplesAutoimmune pancreatitis (AIP) is a recently identified disease of the pancreas with unknown etiology and antigens. The aim of this study was to determine new target antigens and differentially regulated genes and proteins by means of transcriptomics and proteomics and to validate them in patients with autoimmune pancreatitis. Here we report a distinct downregulation at the RNA and protein level of pancreatic proteases (anionic trypsinogen, cationic trypsinogen, mesotrypsinogen, elastase IIIB) and pancreatic stone protein in autoimmune pancreatitis in comparison to alcohol-induced chronic pancreatitis.
Autoantibodies against the exocrine pancreas in autoimmune pancreatitis: gene and protein expression profiling and immunoassays identify pancreatic enzymes as a major target of the inflammatory process.
Sex, Age, Specimen part, Disease
View SamplesWe studied the KRAS and NRAS mutational status in pediatric MLL-AF4+ leukemia patients by means of ultra deep amplicon sequencing. The gene expression profiles of RAS wild type and RAS mutated patients were investigated by gene expression analysis. We showed that mutated patients were characterized by a RAS related expression signature.
Deciphering KRAS and NRAS mutated clone dynamics in MLL-AF4 paediatric leukaemia by ultra deep sequencing analysis.
Specimen part, Disease, Disease stage, Subject
View SamplesBackground: Moderate hypothermia (32oC for 12 72 hours) has therapeutic applications, but the mechanisms by which it affects cellular function are unclear. We tested the hypothesis that moderate hypothermia produces broad changes in gene expression by human cells at the level of mRNA.
Effect of moderate hypothermia on gene expression by THP-1 cells: a DNA microarray study.
No sample metadata fields
View SamplesLong-term maintenance of spermatogenesis in mammals is supported by GDNF, an essential growth factor required for spermatogonial stem cell (SSC) self-renewal. Exploiting a transgenic GDNF overexpression model, which expands and normalizes the pool of undifferentiated spermatogonia between Plzf +/+ and Plzf lu/lu mice, we used RNAseq to identify a rare subpopulation of cells that express EOMES, a T-box transcription factor. Lineage tracing, conditional ablation, and busulfan challenge show that these are long-term SSCs that contribute to steady state spermatogenesis as well as regeneration following chemical injury. EOMES+ SSCs have a lower proliferation index than EOMES- GFRA1+ spermatogonia in wild-type but not in Plzf lu/lu mice. This comparison demonstrates that PLZF regulates their proliferative activity and suggests that EOMES+ SSCs are lost through proliferative exhaustion in Plzf lu/lu mice. Single cell RNA sequencing of EOMES+ cells from Plzf +/+ and Plzf lu/lu mice support a hierarchical model of a slow-cycling long-term SSC population supporting more rapid-cycling short-term SSCs. Overall design: 384-well plate-based 3'-end scRNA-seq was performed on two groups, Plzf +/+ and Plzf lu/lu, of cells across 4 plates. Plzf +/+ cells were spread across 2 plates and Plzf lu/lu cells were spread over 1 plate. The 4th plate contains both Plzf lu/lu (up to well C15) and Plzf +/+ (well C15 onward). Each sample in this record represents one plate.
Identification of EOMES-expressing spermatogonial stem cells and their regulation by PLZF.
Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Response of gastric epithelial progenitors to Helicobacter pylori Isolates obtained from Swedish patients with chronic atrophic gastritis.
Age, Specimen part, Treatment
View SamplesBackground: Gene expression variation is a phenotypic trait of particular interest as it represents the initial link between genotype and other phenotypes. Analyzing how such variation apportions among and within groups allows for the evaluation of how genetic and environmental factors influence such traits. It also provides opportunities to identify genes and pathways that may have been influenced by non-neutral processes. Here we use a population genetics framework and next generation sequencing to evaluate how gene expression variation is apportioned among four human groups in a natural biological tissue, the placenta. Results: We estimate that on average, 33.2%, 58.9% and 7.8% of the placental transcriptome is explained by variation within individuals, among individuals and among human groups, respectively. Additionally, when technical and biological traits are included in models of gene expression they account for roughly 2% of total gene expression variation. Notably, the variation that is significantly different among groups is enriched in biological pathways associated with immune response, cell signaling and metabolism. Many biological traits demonstrated correlated changes in expression in numerous pathways of potential interest to clinicians and evolutionary biologists. Finally, we estimate that the majority of the human placental transcriptome (65% of expressed genes) exhibits expression profiles consistent with neutrality; the remainder are consistent with stabilizing selection (26%), directional selection (4.9%), or diversifying selection (4.8%). Conclusion: We apportion placental gene expression variation into individual, population and biological trait factors and identify how each influence the transcriptome. Additionally, we advance methods to associate expression profiles with different forms of selection. Overall design: Placental mRNA was sequenced on an Illumina GAIIx. Samples were derived from 4 human groups, 10 individuals per group, 2 samples per individual
Evaluating intra- and inter-individual variation in the human placental transcriptome.
No sample metadata fields
View SamplesHelicobacter pylori infection is associated with development of gastric adenocarcinoma in a subset of infected humans, especially those that develop an antecedent condition, chronic atrophic gastritis (ChAG) characterized by loss of acid-producing parietal cells. Studies in a gnotobiotic transgenic mouse model of ChAG, with an engineered ablation of parietal cells and an associated expansion of gastric epithelial progenitors (GEPs), have shown that a subset of GEPs is able to harbor intracellular collections of H. pylori. To better understand H. pyloris adaptation to ChAG, we sequenced the genomes of 24 isolates, obtained from 6 individuals, each sampled over a 4-year interval, as they maintained normal gastric histology, or progressed from normal histology to ChAG, or experienced worsening ChAG, or proceeded from ChAG to cancer. Analyses of gene content and single nucleotide polymorphisms (SNPs) demonstrated that H. pylori populations within study participants were largely clonal, and remarkably stable over the 4-year interval, regardless of disease state. Because they exhibited such broad inter-host variation (38.64.7 SNPs/1000bp of genome), and did not cluster according to host pathology, we sought to identify common functional properties by performing GeneChip studies of the responses of a cultured mouse gastric stem cell-like line (mGEPs) to infection with sequenced strains. The results yielded a shared 695-member set of genes differentially expressed after infection with ChAG-associated, but not normal or heat killed strains: 434 of these genes were also represented in dataset of responses to the cancer-associated strain. Ingenuity Pathway Analysis revealed that ChAG- and ChAG/cancer- associated responses were significantly enriched in genes associated with tumorigenesis in general, and gastric carcinogenesis in specific cases. Whole genome transcriptional profiling of a sequenced ChAG strain during mGEP infection disclosed a set of responses that included upregulation of hopZ, an adhesin belonging to a family of outer membrane proteins. Expression profiles of wild-type and hopZ strains revealed a number of pH-regulated genes affected by loss of HopZ, including HopP which binds sialylated glycans produced by GEPs in vivo. Genetic inactivation of hopZ produces a fitness defect in gnotobiotic transgenic mice but not their wild-type littermates. This study illustrates an approach for identifying GEP responses specific to ChAG, and bacterial genes important for survival in a gastric ecosystem that lacks parietal cells.
Response of gastric epithelial progenitors to Helicobacter pylori Isolates obtained from Swedish patients with chronic atrophic gastritis.
Age, Specimen part, Treatment
View SamplesThe glycopeptide antibiotic vancomycin (VCM) represents one of the last lines of defense against methicillin-resistant Staphylococcus aureus infections. However, vancomycin is nephrotoxic, but the mechanism of toxicity is still unclear.
Gene expression analysis reveals new possible mechanisms of vancomycin-induced nephrotoxicity and identifies gene markers candidates.
Specimen part
View SamplesTranscriptome analyses on seeds developed in different parental conditions
Effects of Parental Temperature and Nitrate on Seed Performance are Reflected by Partly Overlapping Genetic and Metabolic Pathways.
No sample metadata fields
View Samples