CD38, a multi-functional membrane receptor and enzyme, consumes NAD+ to generate products such as cyclic-ADP-ribose. CD38 knockout mice show elevated tissue and blood NAD+ level. Chronic feeding of high-fat, high-sucrose diet to wild type mice leads to exercise intolerance and reduced metabolic flexibility. Loss of CD38 by genetic mutation protects mice from diet-induced metabolic deficit. These animal model results suggest that elevation of tissue NAD+ through genetic ablation of CD38 can profoundly alter energy homeostasis in animals that are maintained on a calorically-excessive Western diet.
Genetic Ablation of CD38 Protects against Western Diet-Induced Exercise Intolerance and Metabolic Inflexibility.
Specimen part
View SamplesThis study aims at identifying genes that are NIK/NF-kappaB2 responsive in murine dendritic cells matured in vivo.
Dendritic cells require the NF-kappaB2 pathway for cross-presentation of soluble antigens.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Mutation of senataxin alters disease-specific transcriptional networks in patients with ataxia with oculomotor apraxia type 2.
Disease
View SamplesSenataxin, encoded by the SETX gene, contributes to multiple aspects of gene expression, including transcription and RNA processing. Mutations in SETX cause the recessive disorder ataxia with oculomotor apraxia type 2 (AOA2) and a dominant juvenile form of amyotrophic lateral sclerosis (ALS4). To assess the functional role of senataxin in disease, we examined differential gene expression in AOA2 patient fibroblasts, identifying a core set of genes showing altered expression by microarray and RNA-sequencing. To determine whether AOA2 and ALS4 mutations differentially affect gene expression, we overexpressed disease-specific SETX mutations in senataxin-haploinsufficient fibroblasts and observed changes in distinct sets of genes. This implicates mutation-specific alterations of senataxin function in disease pathogenesis and provides a novel example of allelic neurogenetic disorders with differing gene expression profiles. Weighted gene co-expression network analysis (WGCNA) demonstrated these senataxin-associated genes to be involved in both mutation-specific and shared functional gene networks. To assess this in vivo, we performed gene expression analysis on peripheral blood from members of 12 different AOA2 families and identified an AOA2-specific transcriptional signature. WGCNA identified two gene modules highly enriched for this transcriptional signature in the peripheral blood of all AOA2 patients studied. These modules were disease-specific and preserved in patient fibroblasts and in the cerebellum of Setx knockout mice demonstrating conservation across species and cell types, including neurons. These results identify novel genes and cellular pathways related to senataxin function in normal and disease states, and implicate alterations in gene expression as underlying the phenotypic differences between AOA2 and ALS4.
Mutation of senataxin alters disease-specific transcriptional networks in patients with ataxia with oculomotor apraxia type 2.
No sample metadata fields
View SamplesDiffuse intrinsic pontine glioma (DIPG) is an incurable pediatric brain tumor, resulting in the death of 200-300 children each year in the United States. Recently it was discovered that approximately 25% of all DIPG cases harbor activating mutations in ACVR1, a gene that encodes Activin A receptor (ALK2), a receptor in the bone morphogenetic protein (BMP) pathway, and that DIPGs with ALK2 mutations commonly harbor an H3.1K27M mutation. Herein, we used the RCAS/TVA retroviral system to study the effects of ACVR1 mutations and H3.1K27M on DIPG pathogenesis. In vitro expression of R206H ACVR1 with and without H3.1K27M in nestin-expressing brainstem progenitors resulted in upregulation of mesenchymal markers and gene set enrichment analysis (GSEA) revealed Stat3 pathway activation. Neonatal expression of ACVR1 R206H or G328V in combination with H3.1K27M and p53 deletion in nestin-expressing brainstem progenitors induced glioma-like lesions expressing mesenchymal markers with Stat3 activation but was not sufficient for full gliomagenesis. In combination with platelet-derived growth factor A (PDGFA) signaling, ACVR1 R206H and H3.1K27M significantly decreased survival and increased tumor incidence. We demonstrate that targeting the BMP signaling pathway may be an effective therapeutic strategy to treat ACVR1 R206H mutant DIPGs. Exogenous Noggin expression at tumor initiation significantly increased tumor latency and treatment of ACVR1 R206H mutant murine DIPGs with LDN212854, an ACVR1 inhibitor, significantly prolonged their survival. We confirm relevance of our model to the human disease as human DIPG models with ACVR1 mutations were also sensitive to treatment with LDN212854 in vitro. Altogether, our studies demonstrate that ACVR1 R206H and H3.1K27M promote tumor initiation, accelerate gliomagenesis, promote a mesenchymal profile in part due to Stat3 activation, and identify LDN212854 as a promising compound to treat children with DIPG. Overall design: We use RNAseq to study the transcriptomal effects of ACVR1 WT or R206H ACVR1 mutation alone and in combination with H3.1K27M mutation on murine nestin-expressing brainstem progenitors at P3-5 (using RCAS/TVA). Key findings were validated by Real-Time PCR.
ACVR1 R206H cooperates with H3.1K27M in promoting diffuse intrinsic pontine glioma pathogenesis.
Specimen part, Subject
View SamplesPrevious studies have shown that ischemia alters gene expression in normal and malignant tissues. There are no studies that evaluated effects of ischemia in renal tumors. This study examines the impact of ischemia and tissue procurement conditions on RNA integrity and gene expression in renal cell carcinoma.
Impact of ischemia and procurement conditions on gene expression in renal cell carcinoma.
Specimen part, Treatment, Subject
View SamplesDetermining which genes are expressed in mechanoreceptor-rich tissue (pedicel) compared mechanoreceptor-poor tissue (capitellum) and a neuronal subtraction control (thoracic ganglion) in Drosophila melanogaster
A doublecortin containing microtubule-associated protein is implicated in mechanotransduction in Drosophila sensory cilia.
Sex, Age, Specimen part
View SamplesHuman bone marrow is a complex, diversified and well-organized hematopoietic network changing composition with age. The purpose of this study was to analyze variations in relative precursor B cell abundance in bone marrow with age by means of global gene expression profiling. RNA was isolated from composite bone marrow from 25 healthy children, adolescents and adults age 2 months to 28 years. As reference transcript for precursor B cells we used recombination activating gene RAG1 exploring the data for other transcripts showing the same profile as RAG1 with age. We identified 54 genes with correlated expression profiles to RAG1 (r 0.9, p = 0), characterized by high expression at 3 - 20 months followed by a fast decline to lower signal levels maintained until early adulthood. Immunophenotyping from a similar healthy age-matched cohort (n = 37) showed a comparable decrease of precursor B cells. Of the 54 genes 15 were characteristically B cell associated representing cell surface molecules (CD19, CD72, CD79A, CD79B, CD180, IGL@, IGLL1, VPREB1, VPREB3), a signal transduction molecule (BLNK) and transcription factors (DNTT, EBF1, PAX5, POU2AF1, RAG2). Of the remaining transcripts some may represent novel B cell transcripts or genes involved in control of B cells.
Striking decrease in the total precursor B-cell compartment during early childhood as evidenced by flow cytometry and gene expression changes.
No sample metadata fields
View SamplesCentral to the molecular pathogenesis of MLL leukaemia is the abnormal co-optation of members of transcription complexes including disrupter of telomeric silencing 1-like (DOT1L) and bromodomain containing protein 4 (BRD4). Consequently, targeted therapies against DOT1L and BRD4 are currently being evaluated in clinical trials. However, the mechanisms by which BRD4 and DOT1L regulate leukaemogenic transcription programs remain unclear. Using quantitative proteomics, chemoproteomics and biochemical fractionation we find that native BRD4 and DOT1L exist in largely separate protein complexes. Genetic disruption or small molecule inhibition of BRD4 and DOT1L shows marked synergistic activity against MLL-FP leukaemia cell lines, primary human leukaemia cells and murine leukaemia models. Mechanistically, we find a previously unrecognised functional collaboration between DOT1L and BRD4 that is especially important at highly transcribed genes in close proximity to superenhancers. DOT1L via H3K79me2 facilitates the deposition of histone H4 acetylation, which in turn regulates the binding of BRD4 to chromatin. These data provide novel insights into the regulation of transcription and specify a molecular framework for therapeutic intervention in this poor prognostic disease. Overall design: RNASeq of MV4;11 cells transduced with scramble shRNA or BRD4 shRNA in combination with DMSO or SGC0946 in triplicate
Functional interdependence of BRD4 and DOT1L in MLL leukemia.
Specimen part, Cell line, Subject
View SamplesCentral to the molecular pathogenesis of MLL leukaemia is the abnormal co-optation of members of transcription complexes including disrupter of telomeric silencing 1-like (DOT1L) and bromodomain containing protein 4 (BRD4). Consequently, targeted therapies against DOT1L and BRD4 are currently being evaluated in clinical trials. However, the mechanisms by which BRD4 and DOT1L regulate leukaemogenic transcription programs remain unclear. Using quantitative proteomics, chemoproteomics and biochemical fractionation we find that native BRD4 and DOT1L exist in largely separate protein complexes. Genetic disruption or small molecule inhibition of BRD4 and DOT1L shows marked synergistic activity against MLL-FP leukaemia cell lines, primary human leukaemia cells and murine leukaemia models. Mechanistically, we find a previously unrecognised functional collaboration between DOT1L and BRD4 that is especially important at highly transcribed genes in close proximity to superenhancers. DOT1L via H3K79me2 facilitates the deposition of histone H4 acetylation, which in turn regulates the binding of BRD4 to chromatin. These data provide novel insights into the regulation of transcription and specify a molecular framework for therapeutic intervention in this poor prognostic disease. Overall design: RNASeq of MLL-AF9 cells transduced with scramle shRNA or BRD4 shRNA in combination with DMSO or SGC0946 in triplicate
Functional interdependence of BRD4 and DOT1L in MLL leukemia.
Specimen part, Cell line, Treatment, Subject
View Samples