The spatial organization of DNA in the cell nucleus is an emerging key contributor to genomic function. We have developed 4C technology, or 3C-on-chip, which allows for an unbiased genome-wide search for DNA loci that contact a given locus in the nuclear space. We demonstrate here that active and inactive genes are engaged in many long-range intrachromosomal interactions and can also form interchromosomal contacts. The active b-globin locus in fetal liver contacts mostly transcribed, but not necessarily tissue-specific, loci elsewhere on chromosome 7, while the inactive locus in fetal brain contacts different, transcriptionally silent, loci. A housekeeping gene in a gene dense region on chromosome 8 forms long-range contacts predominantly with other active gene clusters, both in cis and in trans, and many of these intra- and interchromosomal interactions are conserved between the tissues analyzed. Our data demonstrate that chromosomes fold into areas of active chromatin and areas of inactive chromatin and establish 4C technology as a powerful tool to study nuclear architecture.
Nuclear organization of active and inactive chromatin domains uncovered by chromosome conformation capture-on-chip (4C).
Specimen part
View SamplesMammalian 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 SamplesThis SuperSeries is composed of the SubSeries listed below.
A tissue-specific landscape of sense/antisense transcription in the mouse intestine.
Specimen part
View SamplesGenome wide expression profiling to determine the overlap of Affymetrix-signals with SOLID sequencing
A tissue-specific landscape of sense/antisense transcription in the mouse intestine.
Specimen part
View SamplesThe HSA21-mES Cell Bank includes, in triplicate clones, thirty-two murine orthologs of HSA21 genes, which can be overexpressed in an inducible manner using the Tet-off system integrated in the Rosa26 locus.
A mouse embryonic stem cell bank for inducible overexpression of human chromosome 21 genes.
Specimen part
View SamplesHuman Immunodeficiency Virus (HIV) associated nephropathy (HIVAN) is characterized clinically by both nephrosis and by rapidly progressive kidney dysfunction. HIVAN is characterized histologically by both collapsing focal segmental glomerulosclerosis and prominent tubular damage. Neutrophil Gelatinase Associated Lipocalin (NGAL) is known to be rapidly expressed in distal segments of the nephron at the onset of different types of acute kidney injury, but few studies have examined NGAL in chronic kidney disease models. We found that urinary NGAL (uNGAL) was highly expressed by patients with biopsy proven HIVAN, whereas HIV+ patients without HIVAN demonstrated lower levels. uNGAL was also highly expressed in the TgFVB mouse model of HIVAN, which demonstrated NGAL gene expression in dilated, microcystic segments of the nephron. These data show that NGAL is markedly upregulated in the setting of HIVAN, and suggest that uNGAL levels may provide a non-invasive screening test to detect HIVAN related tubular disease.
Urinary NGAL marks cystic disease in HIV-associated nephropathy.
No sample metadata fields
View SamplesAll highly and poorly permeable metastases from the same mouse brain were collected by laser capture microdissection. Total RNA from both metastatic lesions and immediate microenvironment was isolated from 5 mice bearing 231-BR metastases. As control 4 healthy mouse brains were included.
Reactive astrocytic S1P3 signaling modulates the blood-tumor barrier in brain metastases.
Subject
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 SamplesAffymetrix Human Gene 1.1 ST Array profiling of 285 primary medulloblastoma samples.
Subgroup-specific structural variation across 1,000 medulloblastoma genomes.
Sex, Age
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