This SuperSeries is composed of the SubSeries listed below.
Drosophila H1 regulates the genetic activity of heterochromatin by recruitment of Su(var)3-9.
Specimen part
View SamplesIndicated cells were subjected to RNAi against linker histone H1, Nautilus (control), or GFP (control). RNA was isolated and subjected to Affymetrix GeneChIP Drosophila Genome 2.0 arrays
Drosophila H1 regulates the genetic activity of heterochromatin by recruitment of Su(var)3-9.
Specimen part
View SamplesSalivary glands or larval ovaries were isolated from transgenic flies expressing RNAi targeting Nautilus (control) or linker histone H1 using a Tub-Gal4 driver. Overall design: ~200 larvae were used to isolate salivary glands or ovaries, independently. Total RNA was isolated using Trizol reagent following manufacturer''s guidelines. Then 5 µg of total RNA was separated on a polyacrylamide gel, and 18-29 nt small RNAs were isolated for cloning.
Drosophila H1 regulates the genetic activity of heterochromatin by recruitment of Su(var)3-9.
Specimen part, Subject
View SamplesAnalysis of genes that were differentially expressed in axolotl extract reprogrammed tumour xenografts compared to untreated controls. The study provided insight into the biological processes, signalling pathways and gene networks affected by the oocyte extract treatment which resulted in halted tumour growth in mice.
Cancer reversion with oocyte extracts is mediated by cell cycle arrest and induction of tumour dormancy.
Specimen part, Treatment
View SamplesA LHX4 transgenic reporter line with high specificity for developing mouse cone photoreceptors was identified and used to purify early stage cone photoreceptors for profiling by single cell RNA sequencing. Overall design: Collection of FACS-sorted LHX4::GFP+ E14.5 early cones and LHX4::GFP- retinal cells for further analysis.
Identification of Genes With Enriched Expression in Early Developing Mouse Cone Photoreceptors.
Specimen part, Cell line, Subject
View SamplesHere we report a transcriptomic analysis of fate-restricted progenitor cells biased to produce cone photoreceptors and horizontal cells, marked by the THRB cis-regulatory element ThrbCRM1. Comparison to a control population enriched in multipotent progenitor cells identified several genes considered to be pan-progenitor, such as VSX2, LHX2, and PAX6, as downregulated in these fate-restricted retinal progenitor cells Overall design: Comparison of two FACS-sorted chick retinal progenitor cell populations after electroporation of reporter plasmids and 20hr culture.
Fate-restricted retinal progenitor cells adopt a molecular profile and spatial position distinct from multipotent progenitor cells.
Specimen part, Subject
View SamplesGene expression is regulated both by cis elements, which are DNA segments closely linked to the genes they regulate, and by trans activating factors, which are usually proteins capable of diffusing to unlinked genes. Understanding the patterns and sources of regulatory variation is crucial for understanding phenotypic and genome evolution. Here, we investigate the global patterns of gene expression evolution in Saccharomyces cerivisiae. We report statistical methods useful in quantifying cis and trans regulation using next generation sequencing data. Using these methods, measured genome-wide allele-specific expression by deep sequencing to investigate the genetic architecture of gene regulatory variation between two strains of Saccharomyces cerevisiae. We find that expression polymorphism in yeast is common for both cis and trans regulation, though trans variation is more common. Our detailed analyses of the effects of functional constraint on expression variation as indicated by measures such as protein connectivity, gene essentiality, and the ratio of nonsynonymous substitutions to synonymous substitutions clearly reveal that both classes of variation are under purifying selection, but trans variation is more sensitive to selective constraint. Comparing interspecific expression divergence between S. cerevisiae and S. paradoxus to our intraspecific variation suggests that natural selection strongly influences the patterns of variation we observe. Further analyses revealed that cis divergence is more frequently mediated by positive Darwinian selection than trans divergence, which is compatible with neutral evolution. Overall design: Study the gene expression patterns in two strains of yeast (BY and RM)
Natural selection on cis and trans regulation in yeasts.
Cell line, Subject
View SamplesGlucose is the most important metabolic substrate of the retina and maintenance of nor-moglycemia is an essential challenge for diabetic patients. Glycemic excursions could lead to cardiovascular disease, nephropathy, neuropathy and retinopathy. We recently showed that hy-poglycemia induced retinal cell death in mouse via caspase 3 activation and glutathione (GSH) decrease. Ex vivo experiments in 661W photoreceptor cells confirmed the low-glucose induction of death via superoxide production and activation of caspase 3, which was concomitant with a decrease of GSH content. We evaluate herein retinal gene expression 4 h and 48 h after insulin-induced hypoglycemia. Microarray analysis demonstrated clusters of genes whose expression is modified by hypoglycemia and we discuss the potential implication of those genes in retinal cell death. In addition, we highlight, by gene set enrichment analysis, three important pathways, including KEGG lysosomes, KEGG GSH metabolism and REACTOME apoptosis pathways. We tested the effect of recurrent hypoglycemia (three successive 5h periods of hypoglycemia separated by 48 h recovery) on retinal cell death. Interestingly, exposure to multiple hypoglycemic events prevents retinal cell death and GSH decrease, or adapts the retina to external stress by restoring GSH level comparable to control situation. We hypothesize that scavenger GSH is a key compound in this apoptotic process, and maintaining normal GSH level, as well as a strict glycemic control, may represent a therapeutic challenge in order to avoid side effects of diabetes, especially diabetic retinopathy.
Biological Characterization of Gene Response to Insulin-Induced Hypoglycemia in Mouse Retina.
Sex, Age, Specimen part
View SamplesThe establishment of ad/abaxial polarity is a fundamental event in plant development. It is critical for correct polar development of the leaf (the upper portion of the leaf is chloroplast rich and optimized for light capture while the lower portion is optimized for gas exchange) and for creating an environment that allows the formation of new meristems (centers of stem cell growth). Class III homeodomain-leucine zipper (HD-ZIPIII) proteins are conserved plant proteins that act as potent regulators of ad/abaxial polarity. HD-ZIPIII protein activity promotes the development of upper (adaxial) leaf fates and meristem formation; in its absence lower (abaxial) leaf fates develop and meristems fail to form. A network of regulatory factors controls the establishment of ad/abaxial leaf fates. However, this network is incomplete and how these factors control one another is poorly understood. Here we report a new family of plant genes, the LITTLE ZIPPER (ZPR) genes (consisting principally of a stretch of leucine zipper similar to the leucine zipper in HD-ZIPIII proteins) that are transcriptionally up-regulated by HD-ZIPIII activity. Furthermore, we show that the ZPR proteins interact with and repress HD-ZIPIII activity, thus forming a negative feedback loop. Our results suggest that HD-ZIPIII proteins exist in active homodimers and, together with the ZPR proteins, in inactive heterodimers. The newly discovered HD-ZIPIII/ZPR regulatory module would not only serve to dampen the effect of fluctuations in HD-ZIPIII protein levels but more importantly would provide a point of regulation - control over the ratio of inactive heterodimers to active homodimers - that could be influenced by other components of the pathway. For instance, the binding of a small hydrophobic molecule to the conserved (yet little understood) START domain present in the HD-ZIPIII proteins may influence the type of dimer formed.
A feedback regulatory module formed by LITTLE ZIPPER and HD-ZIPIII genes.
No sample metadata fields
View SamplesNumerous studies have shown the potential of spermatozoal RNAs to delineate failures of spermatogenic pathways in infertile samples. However, the RNA contribution of normal fertile samples still needs to be established in relation to transcripts consistently present in human spermatozoa. We report here the spermatozoal transcript profiles characteristic of 24 normally fertile individuals. RNA was extracted from the purified sperm cells of ejaculate and hybridized to Illumina Human-8 BeadChip Microarrays
Identification of human sperm transcripts as candidate markers of male fertility.
No sample metadata fields
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