Mutations of the transcriptional regulator Mecp2 cause the X-linked autism spectrum disorder Rett syndrome (RTT), and Mecp2 has been implicated in several other neurodevelopmental disorders. To identify potential target genes regulated directly or indirectly by MeCP2, we performed comparative gene expression analysis via oligonucleotide microarrays on Mecp2-/y (Mecp2-null) and wild-type CPN purified via fluorescence-activated cell sorting (FACS).
Reduction of aberrant NF-κB signalling ameliorates Rett syndrome phenotypes in Mecp2-null mice.
Specimen part
View SamplesThroughout postnatal life in mammals, neural stem cells (NSCs) are located in the subventricular zone (SVZ) of the lateral ventricles. The greatest diversity of neuronal and glial lineages they generate occurs during early postnatal life in a region-specific manner. In order to evaluate potential heterogeneity in the NSC pool, we microdissected the dorsal and lateral SVZ at different postnatal ages and isolated NSCs and their immediate progeny based on their expression of Hes5-EGFP/Prominin1 and Ascl1-EGFP, respectively. Whole genome comparative transcriptome analysis revealed transcriptional regulators as major hallmarks that sustain postnatal SVZ regionalization. Manipulation of single genes encoding for locally enriched transcription factors influenced NSC specification indicating that the fate of regionalized postnatal SVZ NSCs can be readily modified . These findings reveal functional heterogeneity of NSCs in the postnatal SVZ and provide targets to recruit region-specific lineages in regenerative contexts.
Transcriptional Hallmarks of Heterogeneous Neural Stem Cell Niches of the Subventricular Zone.
Specimen part
View SamplesUsing a dataset of 54 pregnant and 113 age/stage-matched non-pregnant breast cancer patients with complete clinical and survival data; we evaluated the pattern of hot spot somatic mutations and performed transcriptomic profiling using Sequenom and Affymetrix, respectively. Breast cancer molecular subtypes were defined using PAM50 and 3-Gene classifiers. We performed Gene set enrichment analysis (GSEA) to evaluate pathways associated with diagnosis during pregnancy. We investigated the differential expression of cancer-related genes and published gene sets according to pregnancy. We finally investigated genes associated with disease-free survival.
Biology of breast cancer during pregnancy using genomic profiling.
Age, Disease stage
View SamplesThe zinc finger e-box binding homeobox 1 (ZEB1) transcription factor is a master regulator of the epithelial to mesenchymal transition (EMT), and of the reverse mesenchymal to epithelial transition (MET) processes. ZEB1 plays an integral role in mediating cell state transitions during cell lineage specification, wound healing and disease. EMT/MET are characterized by distinct changes in molecular and cellular phenotype that are generally context-independent. Posterior polymorphous corneal dystrophy (PPCD), associated with ZEB1 insufficiency, provides a new biological context in which to understand and evaluate the classic EMT/MET paradigm. PPCD is characterized by a cadherin-switch and transition to an epithelial-like transcriptomic and cellular phenotype, which we study in a cell-based model of PPCD generated using CRISPR-Cas9-mediated ZEB1 knockout in corneal endothelial cells (CEnCs). Transcriptomic and functional studies support the hypothesis that CEnC undergo an MET-like transition in PPCD, termed endothelial to epithelial transition (EnET), and lead to the conclusion that EnET may be considered a corollary to the classic EMT/MET paradigm. Overall design: Three independent clones for each genotype were generated. ZEB1+/+ and ZEB1+/- (generated using CRISPR-Cas9 gene editing) parental lines were initially generated, then transduced with lentivirus containing ZEB1 cDNA to generate ZEB1 transgenic lines of the parental lines.
ZEB1 insufficiency causes corneal endothelial cell state transition and altered cellular processing.
Subject
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 SamplesThe leaf extract of T. indica had been reported to posses high phenolic content and showed high antioxidant activities. However, scientific data on the molecular mechanisms underlying the beneficial properties of the leaf extract are still lacking. In this study, the effects of the leaf extract on the expression of genes in cultured HepG2 cells were investigated using microarray technology. The leaf extract significantly regulated the expression of genes involved with consequential impact on the coagulation system, cholesterol biosynthesis, xenobiotic metabolism signaling and antimicrobial response.
Investigation into the effects of antioxidant-rich extract of Tamarindus indica leaf on antioxidant enzyme activities, oxidative stress and gene expression profiles in HepG2 cells.
Cell line
View SamplesDeficiency of the micronutrient zinc is a widespread condition in agricultural soils, generating a negative impact on crop quality and yield. Nevertheless, there is insufficient knowledge on the regulatory and molecular mechanisms underlying the plant response to inadequate zinc nutrition.
Transcriptomic profiling of Arabidopsis gene expression in response to varying micronutrient zinc supply.
Age, Specimen part
View SamplesThe water extract of the leaf of B. racemosa had been reported to posses high phenolic content and showed high antioxidant activities. However, scientific data on the molecular mechanisms underlying the beneficial properties of the leaf extract are still lacking. In this study, the effects of the leaf extract on the expression of genes in cultured HepG2 cells were investigated using microarray technology. The leaf extract significantly regulated the expression of genes involved with consequential impact on the glycolysis, gluconeogenesis and metabolism of xenobiotics.
Protective effects of the extracts of Barringtonia racemosa shoots against oxidative damage in HepG2 cells.
Cell line, Treatment
View SamplesThe molecular mechanisms by which individuals subjected to environmental heat stress either adapt or develop heat-related complications are not well understood. We analysed the changes in blood mononuclear gene expression patterns in human volunteers exposed to an extreme heat in a sauna (temperature of 78 6 C).
A Model of Exposure to Extreme Environmental Heat Uncovers the Human Transcriptome to Heat Stress.
Sex, Age, Specimen part, Treatment, Subject, Time
View SamplesSpinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disorder, which is caused by an unstable CAG-repeat expansion in the SCA2 gene, that encodes a polyglutamine tract (polyQ-tract) expansion in ataxin-2 protein (ATXN2). The RNA-binding protein ATXN2 interacts with the poly(A)-binding protein PABPC1, localizing to ribosomes at the rough endoplasmic reticulum or to polysomes. Under cell stress ATXN2 and PABPC1 show redistribution to stress granules where mRNAs are kept away from translation and from degradation. It is unknown whether ATXN2 associates preferentially with specific mRNAs or how it modulates their processing. Here, we investigated Atxn2 knock-out (Atxn2-/-) mouse liver, cerebellum and midbrain regarding their RNA profile, employing oligonucleotide microarrays for screening and RNA deep sequencing for validation. Modest ~1.4-fold upregulations were observed for the level of many mRNAs encoding ribosomal proteins and other translation pathway factors. Quantitative reverse transcriptase PCR and immunoblots in liver tissue confirmed these effects and demonstrated an inverse correlation also with PABPC1 mRNA and protein. ATXN2 deficiency also enhanced phosphorylation of the ribosomal protein S6, while impairing the global protein synthesis rate, suggesting a block between the enhanced translation drive and the impaired execution. Furthermore, ATXN2 overexpression and deficiency retarded cell cycle progression. ATXN2 mRNA levels showed a delayed phasic twofold increase under amino acid and serum starvation, similar to ATXN3, but different from motor neuron disease genes MAPT and SQSTM1. ATXN2 mRNA levels depended particularly on mTOR signalling. Altogether the data implicate ATXN2 in the adaptation of mRNA translation and cell growth to nutrient availability and stress.
Genetic ablation of ataxin-2 increases several global translation factors in their transcript abundance but decreases translation rate.
Age, Specimen part
View Samples