G1ME cells are GATA1-deficient murine bipotential megakaryocyte/erythrocyte progenitor cells derived from Gata1-negative murine ES cells. In order to assess the impact of GATA1 on gene regulation and cell differentiation, an expression construct was used to transiently produce high levels of GATA1. Cells transduced with this construct or a vector control were harvested at 18 and 42 hours, and gene expression was analyzed using Affymetrix MOE430 version 2 arrays.
Graded repression of PU.1/Sfpi1 gene transcription by GATA factors regulates hematopoietic cell fate.
Cell line
View SamplesAnalysis of erythroid differentiation using Gata1 gene-disrupted G1E ER4 clone cells. Estradiol addition activates an ectopically expressed Gata-1-estrogen receptor fusion protein, triggering synchronous differentiation. 30 hour time course corresponds roughly to late burst-forming unit-erythroid stage (t=0 hrs) through orthochromatic erythroblast stage (t=30 hrs).
Erythroid GATA1 function revealed by genome-wide analysis of transcription factor occupancy, histone modifications, and mRNA expression.
Specimen part
View SamplesNeurofibromatosis Type 1 (NF1) patients develop benign neurofibromas and malignant peripheral nerve sheath tumors (MPNST). These incurable peripheral nerve tumors result from loss of NF1 tumor suppressor gene function, causing hyperactive Ras signaling. Activated Ras controls numerous downstream effectors, but specific pathways mediating effects of hyperactive Ras in NF1 tumors are unknown. Cross-species transcriptome analyses of mouse and human neurofibromas and MPNSTs identified global negative feedback of genes that regulate Ras-Raf- MEK- extracellular signal-regulated protein kinase (ERK) signaling in both species. Nonetheless, activation of ERK was sustained in mouse and human neurofibromas and MPNST. PD0325901, a highly selective pharmacological inhibitor of MEK, was used to test whether sustained Ras-Raf-MEK-ERK signaling contributes to neurofibroma growth in the Nf1fl/fl;Dhh-cre mouse model or in NF1 patient MPNST cell xenografts. PD0325901 treatment reduced aberrantly proliferating cells in neurofibroma and MPNST, prolonged survival of mice implanted with human MPNST cells, and shrank neurofibromas in >80% of mice tested. PD0325901 also caused effects on tumor vasculature. Our data demonstrate that deregulated Ras/ERK signaling is critical for the growth of NF1 peripheral nerve tumors and provide strong rationale for testing MEK inhibitors in NF1 clinical trials.
MEK inhibition exhibits efficacy in human and mouse neurofibromatosis tumors.
Specimen part
View SamplesCD38, 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 SamplesDespite advances in investigating functional aspects of osteoblast (OB) differentiation, especially studies on how bone proteins are deposited and mineralized, there has been little research on the intracellular trafficking of bone proteins during OB differentiation. Collagen synthesis and secretion is markedly upregulated upon Ascorbic Acid (AA) stimulation. Understanding the mechanism by which collagen is mobilized in specialized OB cells is important for both basic cell biology and diseases involving defects in bone secretion and deposition. RabGTPases are major regulators on protein trafficking throughout the cell. In this study, we identified the Rab GTPases that are upregulated during 5-day AA differentiation of OBs using microarray analysis, namely Rab1, Rab3d and Rab27b.
Rab GTPase mediated procollagen trafficking in ascorbic acid stimulated osteoblasts.
Specimen part, Cell line
View SamplesPurpose: To identify the changes in postnatal mouse conjunctival forniceal gene expression and their regulation by Klf4 around eye opening stage when the goblet cells first appear.
Mouse conjunctival forniceal gene expression during postnatal development and its regulation by Kruppel-like factor 4.
No sample metadata fields
View SamplesThere are a few markers for embryonic hepatic stellate cells in mouse embryonic livers
Isolation of a unique hepatic stellate cell population expressing integrin α8 from embryonic mouse livers.
Specimen part
View SamplesType I IFN-signaling suppresses an excessive IFN-{gamma} response and prevents lung damage and chronic inflammation following Pneumocystis (PC)-infection and clearance in CD4 T cell-competent mice.
Type-I IFN signaling suppresses an excessive IFN-gamma response and thus prevents lung damage and chronic inflammation during Pneumocystis (PC) clearance in CD4 T cell-competent mice.
Specimen part
View SamplesRationale: While modulation of the serotonin transporter (5HTT) has shown to be a risk factor for pulmonary arterial hypertension for almost 40 years, there is a lack of in vivo data about the broad molecular effects of pulmonary inhibition of 5HTT. Previous studies have suggested effects on inflammation, proliferation, and vasoconstriction. The goal of this study was to determine which of these were supported by alterations in gene expression in serotonin transporter knockout mice. Methods: Eight week old normoxic mice with a 5-HTT knock-out (5HTT-/-) and their heterozygote(5HTT+/-) or wild-type(5HTT+/+) littermates had right ventricular systolic pressure(RVSP) assessed, lungs collected for RNA, pooled, and used in duplicate in Affymetrix array analysis. Representative genes were confirmed by quantitative RT-PCR and western blot. Results: RVSP was normal in all groups. Only 124 genes were reliably changed between 5HTT-/- and 5HTT+/+ mice. More than half of these were either involved in inflammatory response or muscle function and organization; in addition, some matrix, heme oxygenase, developmental, and energy metabolism genes showed altered expression. Quantitative RT-PCR for examples from each major group confirmed changes seen by array, with an intermediate level in 5HTT+/- mice. Conclusions: These results for the first time show the in vivo effects of 5HTT knockout in lungs, and show that many of the downstream mechanisms suggested by cell culture and ex vivo experiments are also operational in vivo. This suggests that the effect of 5HTT on pulmonary vascular function arises from its impact on several systems, including vasoreactivity, proliferation, and immune function.
Gene expression in lungs of mice lacking the 5-hydroxytryptamine transporter gene.
No sample metadata fields
View SamplesSingle O-GlcNAc modification orchestrate by O-GlcNAc Transferase (OGT) and O-GlcNAcase (OGA alias MGEA5) enzymes, affects signal transduction and gene expression by chromatin modulation. We developed Oga deleted MEF (mouse embryonic fibroblast) cells to investigate effects of O-GlcNAc modification in mice. RNA isolated from Mouse Embryonic Fibroblast cells generated from Oga Knock out (KO) Heterozygous (Het) and wild type (WT) cells and subjected to microarray analysis.
Conditional knock-out reveals a requirement for O-linked N-Acetylglucosaminase (O-GlcNAcase) in metabolic homeostasis.
Sex, Specimen part
View Samples