This SuperSeries is composed of the SubSeries listed below.
Functionally distinct patterns of nucleosome remodeling at enhancers in glucocorticoid-treated acute lymphoblastic leukemia.
Specimen part, Cell line
View SamplesPrecise nucleosome positioning is an increasingly recognized feature of promoters and enhancers, reflecting complex contributions of DNA sequence, nucleosome positioning, histone modification and transcription factor binding to enhancer activity and regulation of gene expression. Changes in nucleosome position and occupancy, histone variants and modifications, and chromatin remodeling are also critical elements of dynamic transcriptional regulation, but poorly understood at enhancers. We investigated glucocorticoid receptor-associated (GR) nucleosome dynamics at enhancers in acute lymphoblastic leukemia. For the first time, we demonstrate functionally distinct modes of nucleosome remodeling upon chromatin binding by GR, which we term central, non-central, phased, and minimal. Central and non-central remodeling reflect nucleosome eviction by GR and cofactors, respectively. Phased remodeling involves nucleosome repositioning and is associated with rapidly activated enhancers and induction of gene expression. Minimal remodeling sites initially have low levels of enhancerassociated histone modification, but the majority of these regions gain H3K4me2 or H3K27Ac to become de novo enhancers. Minimal remodeling regions are associated with gene ontologies specific to decreased B cell number and mTOR inhibition and may make unique contributions to glucocorticoid-induced leukemia cell death. Our findings form a novel framework for understanding the dynamic interplay between transcription factor binding, nucleosome remodeling, enhancer function, and gene expression in the leukemia response to glucocorticoids.
Functionally distinct patterns of nucleosome remodeling at enhancers in glucocorticoid-treated acute lymphoblastic leukemia.
Specimen part, Cell line
View SamplesWe analyzed the transcriptional profile of colon and small-intestinal (SI) tissues in response to ex-vivo colonization with members of the gut microbiota. Tissues were dissected from SPF or GF mice, and connected to the ex-vivo gut organ culture system. Then, microbial cultures or fecal samples were infused into the lumen, and tissues were processed in different time points, as indicated below.
An Intestinal Organ Culture System Uncovers a Role for the Nervous System in Microbe-Immune Crosstalk.
Sex, Age
View SamplesSchimke immuno-osseous dysplasia (SIOD) is a multisystemic disorder caused by biallelic mutations in SWI/SNF-related matrix associated actin-dependent regulator of chromatin, subfamily A-like protein 1 (SMARCAL1). Changes in gene expression appear to underlie the immunodeficiency and arteriosclerosis of SIOD; therefore, we hypothesized that SMARCAL1 deficiency alters renal gene expression to cause the focal segmental glomerulosclerosis (FSGS) of SIOD, and that these gene expression alterations would be comparable to those observed in isolated FSGS. We tested this hypothesis by gene expression microarray analysis.
Increased Wnt and Notch signaling: a clue to the renal disease in Schimke immuno-osseous dysplasia?
Sex
View SamplesSchimke immuno-osseous dysplasia (SIOD) is a multisystemic disorder caused by biallelic mutations in SWI/SNF-related matrix associated actin-dependent regulator of chromatin, subfamily A-like protein 1 (SMARCAL1). Changes in gene expression appear to underlie the immunodeficiency and arteriosclerosis of SIOD; therefore, we hypothesized that SMARCAL1 deficiency alters renal gene expression to cause the focal segmental glomerulosclerosis (FSGS) of SIOD. We tested this hypothesis by transcriptome analysis and quantitative reverse transcription PCR (qRT-PCR) of an SIOD patient kidney, a genetic screen and immunofluorescence. These showed increased expression of genes in the Wnt and Notch signaling pathways in an SIOD patient kidney, interaction of Marcal1 with genes encoding components of the Wnt and Notch signaling pathways, and increased levels of unphosphorylated b-catenin and Notch1 intracellular domain (NICD) in the glomeruli of SIOD patient kidneys. Given that increased Wnt and Notch activity are established causes of FSGS, we hypothesize that SMARCAL1 deficiency increases the activity of one or both of these pathways to cause the renal disease of most SIOD patients. Overall design: Comparison of mRNA levels between the kidney tissue of a Schimke immuno-osseous dysplasia (SIOD) patient and an unaffected control
Increased Wnt and Notch signaling: a clue to the renal disease in Schimke immuno-osseous dysplasia?
No sample metadata fields
View Samples