Mammalian genomes contain numerous DNA elements with potential transcription regulatory function but unknown target genes. We used transgenic, gain-of-function mice with an ectopic copy of the beta-globin locus control region (LCR) to better understand how regulatory elements dynamically search the genome for target genes. We find that the LCR samples a restricted nuclear sub-volume in which it forms preferential contacts with genes controlled by shared transcription factors. One contacted gene, betah1, located on another chromosome, is upregulated, providing genetic demonstration that mammalian enhancers can function between chromosomes. Upregulation is not pan-cellular but confined to selected jackpot cells significantly enriched for inter-chromosomal LCR-betah1 interactions. This implies that long-range DNA contacts are relatively stable and cell-specific and, when functional, cause variegated expression. We refer to this as spatial effect variegation (SEV). The data provide a dynamic and mechanistic framework for enhancer action, important for assigning function to the one- and three-dimensional structure of DNA.
Variegated gene expression caused by cell-specific long-range DNA interactions.
Specimen part, Disease
View SamplesThe thymus is extremely sensitive to damage but also has a remarkable ability to repair itself. However, the mechanisms underlying this endogenous regeneration remain poorly understood and this capacity diminishes considerably with age. To identify alternate regeneration pathways in the thymus, we performed an unbiased transcriptome analysis of the non-hematopoietic (CD45-) stromal cell compartment of the thymus, which is less sensitive to thymic damage compared to the CD45+ hematopoietic compartment.
Production of BMP4 by endothelial cells is crucial for endogenous thymic regeneration.
Sex, Specimen part
View SamplesBackground: Lung function is dependent upon the precise regulation of the synthesis, storage, and catabolism of tissue and alveolar lipids.
Activation of sterol-response element-binding proteins (SREBP) in alveolar type II cells enhances lipogenesis causing pulmonary lipotoxicity.
Specimen part
View SamplesExpression profiles generated during dissection of the molecular mechanisms underlying direct reprogramming of somatic cells to a pluripotent state (induced pluripotent stem cells, iPS).
Dissecting direct reprogramming through integrative genomic analysis.
No sample metadata fields
View SamplesThe liver is frequently challenged by surgery-induced metabolic overload, viruses, or toxins, which induce the formation of reactive oxygen species. To determine the effect of oxidative stress on liver regeneration and to identify the underlying signalling pathways, we studied liver repair in mice lacking the Nrf2 transcription factor. In these animals, expression of several cytoprotective enzymes was reduced in hepatocytes, resulting in oxidative stress. As a consequence, tissue damage was aggravated, and liver regeneration after partial hepatectomy was delayed.
Impaired liver regeneration in Nrf2 knockout mice: role of ROS-mediated insulin/IGF-1 resistance.
Specimen part
View SamplesRNA from wt and SIN1 knock-out MEF cell lines were compared
mTORC2 Responds to Glutamine Catabolite Levels to Modulate the Hexosamine Biosynthesis Enzyme GFAT1.
Specimen part
View SamplesWe aimed to define epithelial-specific genes in the kidney. In the developing mouse kidney at E12.5 epithelial cells are restricted to the ureteric bud, while mesenchymal cells surrounding the ureteric bud are non-epithelial. The mouse renal epithelial cell line mIMCD-3 was used to represent kidney epithelia in vitro. Gene expression was analyzed using Affymetrix microarrays in ureteric bud stalks, ureteric bud tips, and mIMCD-3 cells and compared to metanephric mesenchyme.
The transcription factor grainyhead-like 2 regulates the molecular composition of the epithelial apical junctional complex.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Transcription factor <i>TFCP2L1</i> patterns cells in the mouse kidney collecting ducts.
Specimen part
View SamplesWe report a Jak2V617F knock-in mouse myeloproliferative neoplasm (MPN) model resembling human polycythemia vera (PV). The MPN is serially transplantable and we demonstrate that the hematopoietic stem cell (HSC) compartment has the unique capacity for disease initiation but does not have a selective competitive advantage over wild type HSCs. In contrast, myeloid progenitor populations are expanded and skewed towards the erythroid lineage, but cannot transplant the disease. Treatment with a JAK2 kinase inhibitor ameliorated the MPN phenotype, but did not eliminate the disease-initiating population. These findings provide insights into the consequences of JAK2 activation on HSC differentiation and function and have the potential to inform therapeutic approaches to JAK2V617F positive MPN.
Physiological Jak2V617F expression causes a lethal myeloproliferative neoplasm with differential effects on hematopoietic stem and progenitor cells.
Specimen part
View SamplesGene expression analysis of mouse kidney after conditional inactivation of transcription factor Tfcp2l1
Transcription factor <i>TFCP2L1</i> patterns cells in the mouse kidney collecting ducts.
Specimen part
View Samples