The pigmented portion of ciliary epithelium in the adult mammalian eye harbors mitotically quiescent retinal sphere cells, which are capable of self-renewal and differentiating into retinal neurons when assayed in vitro; however, very little is known about the molecular mechanism controlling the proliferation and differentiation of these adult retinal stem cells or their molecular resemblance to mutipotent stem/progenitor cells during early eye development. This experiment studies the gene expression of first passage and primary human and mouse retinal sphere cells.
Recent developments in StemBase: a tool to study gene expression in human and murine stem cells.
Sex
View SamplesThe endocytic receptor megalin constitutes the main pathway for clearance of plasma proteins from the glomerular filtrate in the proximal tubules. However, little is know about the mechanisms that control receptor activity. A widely discussed hypothesis states that the intracellular domain (ICD) of megalin, released upon ligand binding, acts as a transcription regulator to suppress receptor expression - a mechanism proposed to safeguard the proximal tubules from protein overload. Here, we have put this hypothesis to the test by generating a mouse model co-expressing the soluble ICD and the full-length receptor. Despite pronounced expression in the proximal tubules, the ICD failed to exert any effects on renal proximal tubular function such as megalin expression, protein retrieval, or renal gene transcription. Thus, our data argue that the ICD does not play a role in regulation of megalin activity in vivo in the proximal tubules.
The soluble intracellular domain of megalin does not affect renal proximal tubular function in vivo.
Sex, Age, Specimen part
View SamplesOne and four month formalin-fixed paraffin embedded biopsies from 48 kidney transplant recipients (24 AKI donors, 24 non-AKI) underwent global gene expression profiling using DNA microarrays (96 arrays). At one month, there were 898 differentially expressed genes in the AKI group (p-value <0.005; FDR <10%), but by 4-months there were no longer any differences.
Transplanting Kidneys from Deceased Donors With Severe Acute Kidney Injury.
No sample metadata fields
View SamplesAnalysis of hematopoietic stem cells (HSC, LSK Flt3-) and myeloid progenitors (MP, LK CD34+) sorted from wildtype and Dnmt1 hypomorph mice
DNA methylation protects hematopoietic stem cell multipotency from myeloerythroid restriction.
Specimen part
View SamplesFiltered selection coupled with support vector machines generate functionally relevant prediction model for colorectal cancer. In this study, we built a model that uses Support Vector Machine (SVM) to classify cancer and normal samples using Affymetrix exon microarray data obtained from 90 samples of 48 patients diagnosed with CRC. From the 22,011 genes, we selected the 20, 30, 50, 100, 200, 300 and 500 genes most relevant to CRC using the Minimum-RedundancyMaximum-Relevance (mRMR) technique. With these gene sets, an SVM model was designed using four different kernel types (linear, polynomial, radial basis function and sigmoid).
Filtered selection coupled with support vector machines generate a functionally relevant prediction model for colorectal cancer.
Sex, Age, Specimen part, Disease stage
View SamplesPhytophthora cinnamomi is a devastating soil-borne oomycete with a very broad host range however there remains a major gap in the understanding of plant resistance responses to the pathogen, furthermore, necrotrophic plant-pathogen interactions, particularly those of root pathogens, remain poorly understood. Zea mays exhibits non-host resistance to the pathogen and has been well characterised as a model species. Using the maize Affymetrix GeneChip array we conducted genome-wide gene expression profiling to elucidate the defence genes and pathways which are induced in the root tissue of a resistant plant species to the pathogen.
Transcriptional profiling of Zea mays roots reveals roles for jasmonic acid and terpenoids in resistance against Phytophthora cinnamomi.
Specimen part, Time
View SamplesThis study seeks to understand the mechanisms behind enhanced lymphomagenesis observed in ImHABCL6/Uchl1 mice compared with ImHABCL6 alone. As the lymphomas arise from germinal center (GC) B-cells, we reasoned that transgenic Uchl1 altered the gene expression patterns in GC B-cells from these animals. We therefore isolated pre-malignant GC B-cells and examined the gene expression patterns to identify pathways affected by the addition of Uchl1.
UCH-L1 is induced in germinal center B cells and identifies patients with aggressive germinal center diffuse large B-cell lymphoma.
Specimen part
View SamplesDNA methylation is an important epigenetic control mechanism that has been shown to be associated with gene silencing through the course of development, maturation and aging. However, only limited data are available regarding the relationship between methylation and gene expression in human development. We analyzed the methylomes and transcriptomes of three human fetal liver samples (gestational age 20-22 weeks) and three adult human liver samples. Genes whose expression differed between fetal and adult numbered 7,673. Adult overexpression was associated with metabolic pathways and, in particular, cytochrome P450 enzymes, while fetal overexpression reflected enrichment for DNA replication and repair. Analysis for DNA methylation using the Illumina Infinium 450K HumanMethylation BeadChip showed that 42% of the quality filtered 426,154 methylation sites differed significantly between adult and fetal tissue (q0.05). Differences were small; 69% of the significant sites differed in their mean methylation beta value by 0.2. There was a trend among all sites toward higher methylation in the adult samples with the most frequent difference in beta being 0.1. Characterization of the relationship between methylation and expression revealed a clear difference between fetus and adult. Methylation of genes overexpressed in fetal liver showed the same pattern as seen for genes that were similarly expressed in fetal and adult liver. In contrast, adult overexpressed genes showed fetal hypermethylation that differed from the similarly expressed genes. An examination of gene region-specific methylation showed that sites proximal to the transcription start site or within the first exon with a significant fetal-adult difference in beta (>0.2) showed an inverse relationship with gene expression. Nearly half of the CpGs in human liver show a significant difference in methylation comparing fetal and adult samples. Sites proximal to the transcription start site or within the first exon that show a transition from hypermethylation in the fetus to hypomethylation or intermediate methylation in the adult are associated with inverse changes in gene expression. In contrast, increases in methylation going from fetal to adult are not associated with fetal-to-adult decreased expression. These findings indicate fundamentally different roles for and/or regulation of DNA methylation in human fetal and adult liver.
Patterns of gene expression and DNA methylation in human fetal and adult liver.
Sex, Age, Specimen part
View SamplesExcess/residual urea is a pervasion problem in wine and Sake fermentation. We sought to reduce residual urea levels (to reduce ethyl carbamate leves) by engineering the Sake yeast strain K7 to constitutively express either the urea amidolyase (Dur1,2) or urea importer (Dur3). We sought to then compare the gene expression profiles of the metabolically engineered yeast strains to the parental strain during fermentation.
Functional enhancement of Sake yeast strains to minimize the production of ethyl carbamate in Sake wine.
No sample metadata fields
View SamplesThe amount of RNA sequencing data on skeletal muscle is very limited. We have analyzed a large set of human muscle biopsy samples and provide extensive information on the baseline skeletal muscle transcriptome, including completely novel protein-coding transcripts. Overall design: Analyze of transcriptome in 23 skeletal muscle biopsy samples from six individuals. Four biopsies from each subject, two biopsies from each leg (except subject 6 which has only three biopsies in total).
The human skeletal muscle transcriptome: sex differences, alternative splicing, and tissue homogeneity assessed with RNA sequencing.
No sample metadata fields
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