The molecular mechanisms underlying erythroid-specific gene regulation remain incompletely understood. Closely spaced binding sites for GATA, NF-E2/maf and CACCC interacting transcription factors play functionally important roles in globin and other erythroid-specific gene expression. We and others recently identified the CACCC-binding transcription factor ZBP-89 as a novel GATA-1 and NF-E2/mafK interacting partner. Here, we examined the role of ZBP-89 in human globin gene regulation and erythroid maturation using a primary CD34+ cell ex vivo differentiation system. We show that ZBP-89 protein levels rise dramatically during human erythroid differentiation, and that ZBP-89 occupies key cis-regulatory elements within the globin and other erythroid gene loci. ZBP-89 binding correlates strongly with RNA Pol II occupancy, active histone marks, and high-level gene expression. ZBP-89 physically associates with the histone acetyltransferases (HATs) p300 and Gcn5/Trrap, and occupies common sites with Gcn5 within the human globin loci. Lentiviral shRNA knockdown of ZBP-89 results in reduced Gcn5 occupancy, decreased acetylated histone 3 levels, lower globin and erythroid-specific gene expression, and impaired erythroid maturation. Addition of the HDAC inhibitor valproic acid partially reverses the reduced globin gene expression. These findings reveal an activating role for ZBP-89 in human globin gene regulation and erythroid differentiation.
Role of ZBP-89 in human globin gene regulation and erythroid differentiation.
Specimen part
View SamplesThe premature aging disorder Werner Syndrome (WS) is characterized by early onset of aging phenotypes resembling natural aging. In most WS patients there are mutations in the DNA helicase WRN, an enzyme important in maintaining genome stability and telomere replication. Interestingly, its clinical manifestations reflect a severe degree of deterioration for connective tissue, whereas the central nervous system is less affected. We suggest that the varied vulnerability to aging is regulated by an unknown mechanism that protects specific lineages of stem cells from premature senescence. To address this problem, we reprogrammed patient skin fibroblasts to induced pluripotent stem cells (iPSC). The expression profile for the differentiated normal and WS fibroblasts and undifferentiated iPSC were compared. A distinct expression profile was found between normal and WS fibroblasts, however, few changes of gene expression were found in iPSC. Our findings suggest an erasure of aging phenotype associated with WS in reprogrammed iPSC.
Telomerase protects werner syndrome lineage-specific stem cells from premature aging.
Sex, Age, Specimen part
View SamplesEngagement of the ICOS receptor represents a key event in a process that culminates in Bcl6 expression and acquisition of the TFH and TFR phenotype. To better understand the essentials of ICOS-mediated signaling pathway, we profiled the changes in gene expression elicited after co-ligation of ICOS and CD3 compared with CD3 ligation alone.
A p85α-osteopontin axis couples the receptor ICOS to sustained Bcl-6 expression by follicular helper and regulatory T cells.
Specimen part
View SamplesIdentification of genes regulated by GATA-1 independent of the cofactor FOG-1.
Friend of GATA-1-independent transcriptional repression: a novel mode of GATA-1 function.
No sample metadata fields
View SamplesThe objective of this study was to understand the genetic mechanisms of Vitamin-A-Deficiency (VAD)-induced arrest of spermatogonial stem-cell differentiation. Vitamin A and its derivatives (the retinoids) participate in many physiological processes including vision, cellular differentiation and reproduction. VAD affects spermatogenesis, the subject of our present study. Spermatogenesis is a highly regulated process of differentiation and complex morphologic alterations that, in the postnatal testis, leads to the formation of sperm in the seminiferous epithelium. VAD causes early cessation of spermatogenesis, characterized by degeneration of meiotic germ cells, leading to seminiferous tubules containing mostly type A spermatogonia and Sertoli cells. In this study, we investigated the molecular basis of VAD on spermatogenesis in mice. We used adult Balb/C mice fed with a Control or VAD diet for an extended period of time (8-28 weeks) and selected two time points (18 and 25 weeks) for microarray analysis.
Long-term vitamin A deficiency induces alteration of adult mouse spermatogenesis and spermatogonial differentiation: direct effect on spermatogonial gene expression and indirect effects via somatic cells.
Specimen part, Treatment
View SamplesUnderstanding the mechanisms by which long-term memories are formed and stored in the brain represents a central aim of neuroscience. Prevailing theory suggests that long-term memory encoding involves early plasticity within hippocampal circuits, while reorganization of the neocortex is thought to occur weeks to months later to subserve remote memory storage. Here we report that long-term memory encoding can elicit early transcriptional, structural and functional remodeling of the neocortex. Parallel studies using genome-wide RNA-sequencing, ultrastructural imaging, and whole-cell recording in wild-type mice suggest that contextual fear conditioning initiates a transcriptional program in the medial prefrontal cortex (mPFC) that is accompanied by rapid expansion of the synaptic active zone and postsynaptic density, enhanced dendritic spine plasticity, and increased synaptic efficacy. To address the real-time contribution of the mPFC to long-term memory encoding, we performed temporally precise optogenetic inhibition of excitatory mPFC neurons during contextual fear conditioning. Using this approach, we found that real-time inhibition of the mPFC inhibited activation of the entorhinal-hippocampal circuit and impaired the formation of long-term associative memory. These findings suggest that encoding of long-term episodic memory is associated with early remodeling of neocortical circuits, identify the prefrontal cortex as a critical regulator of encoding-induced hippocampal activation and long-term memory formation, and have important implications for understanding memory processing in healthy and diseased brain states. Overall design: 4 biological replicates per group were analyzed. The material analyzed was medial prefrontal cortex (mPFC; anterior cingulate cortex subregion) from both brain hemispheres, from which total RNA was extracted.
Early remodeling of the neocortex upon episodic memory encoding.
No sample metadata fields
View SamplesAbout 10% of Down syndrome (DS) infants are born with a myeloproliferative disorder (DS-TMD) that spontaneously resolves within the first few months of life. About 20-30% of these infants subsequently develop acute megakaryoblastic leukemia (DS-AMKL). In order to understand differences that may exist between fetal and bone marrow megakaryocyte progenitor cell populations we flow sorted megakaryocyte progenitor cells and performed microarray expression analysis.
Developmental differences in IFN signaling affect GATA1s-induced megakaryocyte hyperproliferation.
Specimen part
View SamplesAbout 10% of Down syndrome (DS) infants are born with a myeloproliferative disorder (DS-TMD) that spontaneously resolves within the first few months of life. About 20-30% of these infants subsequently develop acute megakaryoblastic leukemia (DS-AMKL). In order to understand differences that may exist between fetal and bone marrow megakaryocyte progenitor cell populations we flow sorted megakaryocyte progenitor cells and performed microarray expression analysis.
Developmental differences in IFN signaling affect GATA1s-induced megakaryocyte hyperproliferation.
Specimen part
View SamplesWe report differences in gene expression between WT and Bmi1 KO pro-B cells. Overall design: RNA profiles from WT and Bmi1 KO pro-B cells were generated in duplicate.
Impaired Expression of Rearranged Immunoglobulin Genes and Premature p53 Activation Block B Cell Development in BMI1 Null Mice.
Specimen part, Cell line, Subject
View SamplesPancreatic ductal adenocarcinoma (PDAC) is strikingly resistant to conventional approaches. In this study, we report that the histone deacetylase associated SIN3B protein is required for activated KRAS-induced senescence in vivo using a mouse model of pancreatic cancer.
Senescence-associated SIN3B promotes inflammation and pancreatic cancer progression.
Specimen part
View Samples