This experiment was designed to identify genes expressed preferentially in the two integuments of the Arabidopsis ovule. Pistils from wild type and two ovule mutants were compared against each aintegumenta-4 (ant-4) which lacks both integuments and inner no outer (ino-1) which lacks the outer integument. Genes that are highly expressed only in the integuments were expected to be reduced in expression in the mutants, as compared with wild type. Pistils containing ovules through all stages of ovule development prior to pollination were pooled for one experiment (FULL arrays), and for two separate experiments, a set of early differentiation stages (EARLY arrays) and a set of later differentiation stages (LATE ARRAYS) were pooled. Wild type and mutant lines are in the ecotype Landsberg erecta.
Expression-based discovery of candidate ovule development regulators through transcriptional profiling of ovule mutants.
Specimen part
View SamplesMicroarray expression profiling has become a valuable tool in the evaluation of the genetic consequences of metabolic disease. Although 3-biased gene expression microarray platforms were the first generation to have widespread availability, newer platforms are gradually emerging that have more up-to-date content and/or higher cost efficiency. Deciphering the relative strengths and weaknesses of these various platforms for metabolic pathway level analyses can be daunting. We sought to determine the practical strengths and weaknesses of four leading commercially-available expression array platforms relative to biologic investigations, as well as assess the feasibility of cross-platform data integration for purposes of biochemical pathway analyses. METHODS: Liver RNA from B6.Alb/cre,Pdss2loxP/loxP mice having primary Coenzyme Q deficiency was extracted either at baseline or following treatment with an antioxidant/antihyperlipidemic agent, probucol. Target RNA samples were prepared and hybridized to Affymetrix 430 2.0, Affymetrix Gene 1.0 ST, Affymetrix Exon 1.0 ST, and Illumina Mouse WG-6 expression arrays. Probes on all platforms were re-mapped to coding sequences in the current version of the mouse genome. Data processing and statistical analysis were performed by R/Bioconductor functions, and pathway analyses were carried out by KEGG Atlas and GSEA. RESULTS: Expression measurements were generally consistent across platforms. However, intensive probe-level comparison suggested that differences in probe locations were a major source of inter-platform variance. In addition, genes expressed at low or intermediate levels had lower inter-platform reproducibility than highly expressed genes. All platforms showed similar patterns of differential expression between sample groups, with steroid biosynthesis consistently identified as the most down-regulated metabolic pathway by probucol treatment. CONCLUSIONS: This work offers a timely guide for metabolic disease investigators to enable informed end-user decisions regarding choice of expression microarray platform best-suited to specific research project goals. Successful cross-platform integration of biochemical pathway expression data is also demonstrated, especially for well-annotated and highly-expressed genes. However, integration of gene-level expression data is limited by individual platform probe design and the expression level of target genes. Cross-platform analyses of biochemical pathway data will require additional data processing and novel computational bioinformatics tools to address unique statistical challenges.
Cross-platform expression microarray performance in a mouse model of mitochondrial disease therapy.
Sex, Age, Specimen part, Treatment
View SamplesFunctional analysis of ABCB5 in A375 and G3361 melanoma cells, by comparing stably-transfected controls to ABCB5-shRNA-targeted cells.
ABCB5 maintains melanoma-initiating cells through a proinflammatory cytokine signaling circuit.
Specimen part, Cell line
View SamplesRNA-seq for monitoring expression levels in mutants that do not anchor chromatin at the nuclear periphery. Overall design: RNA-seq of depleted rRNA samples of early embryo extracts for three different genotypes: wild-type, cec-4_delta and met-2 set-25_delta_delta, in two independent biological replicas
Perinuclear Anchoring of H3K9-Methylated Chromatin Stabilizes Induced Cell Fate in C. elegans Embryos.
Cell line, Subject
View SamplesMelanoma growth is driven by malignant melanoma initiating cells (MMIC) identified by expression of the ATP-binding cassette (ABC) member, ABCB5. ABCB5+ melanoma subpopulations have been shown to overexpress the vasculogenic differentiation markers CD144 (VE-cadherin) and TIE-1 and are associated with CD31-negative vasculogenic mimicry (VM), an established biomarker associated with increased patient mortality. Here we identify a critical role for VEGFR-1 signaling in ABCB5+ MMIC-dependent VM and tumor growth. Global gene expression analyses, validated by mRNA and protein determinations, revealed preferential expression of VEGFR-1 on ABCB5+ tumor cells purified from clinical melanomas and established melanoma lines. In vitro, VEGF induced in a VEGFR-1-dependent manner expression of CD144 in ABCB5+ subpopulations that constitutively expressed VEGFR-1, but not in ABCB5- bulk populations that were predominantly VEGFR-1-negative. In vivo, melanomaspecific shRNA-mediated knockdown of VEGFR-1 blocked the development of ABCB5+ VM morphology and inhibited ABCB5+ VM-associated production of the secreted melanoma mitogen, laminin. Moreover, melanoma-specific VEGFR-1 knockdown markedly inhibited tumor growth (by >90%). Our results demonstrate that VEGFR-1 function in MMIC regulates VM and associated laminin production, and show that this function represents one mechanism through which MMIC promote tumor growth.
VEGFR-1 expressed by malignant melanoma-initiating cells is required for tumor growth.
Specimen part
View SamplesUtilizing M. musculus as a model of mitochondrial dysfunction provides insight into cellular adaptations which occur as a consequence of genetic alterations causative of human disease. We characterized genome-wide expression profiles of liver-conditional knockout mice for Pdss2 compared with loxP controls.
Primary coenzyme Q deficiency in Pdss2 mutant mice causes isolated renal disease.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Heterochromatin Protein 1β (HP1β) has distinct functions and distinct nuclear distribution in pluripotent versus differentiated cells.
Specimen part, Cell line
View SamplesWe used microarrays to identify the gene expression changes in Cbx1-/- (HP1beta) knockout embryonic stem cells (ESCs) and Cbx5-/- (HP1alpha) knockout ESCs compared to WT ESCs and in embryoid bodies (EBs) differentiated from those three ESC types.
Heterochromatin Protein 1β (HP1β) has distinct functions and distinct nuclear distribution in pluripotent versus differentiated cells.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Disease-associated miRNA-mRNA networks in oral lichen planus.
Specimen part, Disease, Disease stage
View SamplesThe experiment aims to identify regulatory miRNA networks influencing mRNA profiles in oral lichen planus (OLP). RNA and miRNA were extracted simultaniously using miRVana (Ambion, Life Technologies). Sample and array processing was carried out according to the manufacturer's guidelines. Affymetrix raw data was processed using AGCC Expression Console 1.1 (Affymetrix), employing RMA normalization. Linking miRNA and mRNA was performed with a correlation analysis, while a false discovery rate was used to exclude false-positive correlations between miRNAs and their predicted targets.
Disease-associated miRNA-mRNA networks in oral lichen planus.
Specimen part, Disease, Disease stage
View Samples