Rosiglitazone (Rosi), a member of the thiazolidinedione class of drugs used to treat type 2 diabetes, activates the adipocyte-specific transcription factor peroxisome proliferator-activated receptor gamma (PPARg). This activation causes bone loss in animals and humans, at least in part due to suppression of osteoblast differentiation from marrow mesenchymal stem cells (MSC). In order to identify mechanisms by which PPARg2 suppresses osteoblastogenesis and promotes adipogenesis in MSC, we have analyzed the PPARg2 transcriptome in response to Rosi. A total of 4,252 transcriptional changes resulted when Rosi (1 uM) was applied to the U-33 marrow stromal cell line, stably transfected with PPARg2 (U-33/g2), as compared to non-induced U-33/g2 cells. Differences between U-33/g2 and U-33 cells stably transfected with empty vector (U-33/c) comprised 7,928 transcriptional changes, independent of Rosi. Cell type-, time- and treatment-specific gene clustering uncovered distinct patterns of PPARg2 transcriptional control of MSC lineage commitment. The earliest changes accompanying Rosi activation of PPARg2 included adjustments in morphogenesis, Wnt signaling, and immune responses, as well as sustained induction of lipid metabolism. Expression signatures influenced by longer exposure to Rosi provided evidence for distinct mechanisms governing the repression of osteogenesis and stimulation of adipogenesis. Our results suggest interactions that could lead to the identification of a master regulatory scheme controlling osteoblast differentiation.
PPARgamma2 nuclear receptor controls multiple regulatory pathways of osteoblast differentiation from marrow mesenchymal stem cells.
Compound, Time
View SamplesSeveral studies have shown that bone mineral density (BMD), a clinically measurable predictor of osteoporotic fracture, is the sum of genetic and environmental influences. In addition, serum IGF-1 levels have been correlated to both BMD and fracture risk. We previously identified a Quantitative Trait Locus (QTL) for Bone Mineral Density (BMD) on mouse Chromosome (Chr) 6 that overlaps a QTL for serum IGF-1. The B6.C3H-6T (6T) congenic mouse is homozygous for C57BL/6J (B6) alleles across the genome except for a 30 cM region on Chr 6 that is homozygous for C3H/HeJ (C3H) alleles. This mouse was created to study biology behind both the BMD and the serum IGF-1 QTLs and to identify the gene(s) underlying these QTLs. Female 6T mice have lower BMD and lower serum IGF-1 levels at all ages measured. As the liver is the major source of serum IGF-1, we examined differential expression in the livers of fasted female B6 and 6T mice by microarray.
A chromosomal inversion within a quantitative trait locus has a major effect on adipogenesis and osteoblastogenesis.
No sample metadata fields
View SamplesDisruption of N-linked glycosylation has a broad impact on proper glycosylation of nascent glycoproteins in the endoplasmic reticulum, which affect multiple signalling pathways( by changing the stability of membrane proteins or the signalling ability of membrane receptors) and may be responsible of the fibrotic stage associated to CDG type-I.
Fibrotic response in fibroblasts from congenital disorders of glycosylation.
No sample metadata fields
View SamplesThis work uses a time series in order to decipher gene relationships and consequently to build core regulatory networks involved in Arabidopsis root adaptation to NO3- provision. The experimental approach has been to monitor genome response to NO3- at 3, 6, 9, 12, 15 and 20 min, using ATH1 chips. This high-resolution time course analysis demonstrated that the previously known primary nitrate response is actually preceded by very fast (within 3 min) gene expression modulation, involving genes/functions needed to prepare plants to use/reduce NO3-. State-space modeling (a machine learning approach) has been used to successfully predict gene behavior in unlearnt conditions.
Predictive network modeling of the high-resolution dynamic plant transcriptome in response to nitrate.
Specimen part, Treatment
View SamplesPrevious studies in our laboratory have shown that low folate diet (control diet with 2mg folate/kg, low folate diet with 0.3mg folate/kg) can induce intestinal tumors in BALB/c mice. In addition, we reported that C57Bl/6J mice did not form tumors under the same conditions.
Differential gene expression and methylation in the retinoid/PPARA pathway and of tumor suppressors may modify intestinal tumorigenesis induced by low folate in mice.
Sex, Specimen part, Treatment
View SamplesWe address the function of HEXIM, an inhibitor of the general transcriptional elongation regulator P-TEFb which regulates the transcriptional status of many developmental genes, during Drosophila development. We showed that HEXIM knockdown mutants display organs development failure. In the wing disc, it induces apoptosis and affects Hh signaling. The continuous death of proliferative cells is compensated by apoptosis-induced cell proliferation, in a manner similar to that of differentiated cells, together with high levels of Hh and Ci. We completed this analysis with microarrays to characterize the molecular phenotype of HEXIM knockdown during eye differentiation.
Functional Interaction between HEXIM and Hedgehog Signaling during Drosophila Wing Development.
Specimen part
View SamplesXbp1 is an important regulator of unfolded protein response and lipid metabolism. Its dyregulation has been associcated in human NASH. Feeding a high fat diet with fructose/sucrose to mice causes progressive, fibrosing steatohepatitis. This study is to use RNA-Seq to identify differentially expressed genes in hepatic Xbp1 deficient mice livers fed with a high fat diet compared to controls. Overall design: Hepatic Xbp1 deficient mice or flox controls were fed either regular chow or a high fat diet (n=4). Samples from each cohort were pooled into two replicates.
Hepatocyte X-box binding protein 1 deficiency increases liver injury in mice fed a high-fat/sugar diet.
No sample metadata fields
View SamplesNormal human tissue samples from ten post-mortem donors were processed to generate total RNA, which was subsequently analyzed for gene expression using Affymetrix U133 plus 2.0 arrays. Donor information: Donor 1 - 25 year old male; donor 2 - 38 year old male; donor 3 - 39 year old female; donor 4 - 30 year old male; donor 5 - 35 year old male; donor 6 - 52 year old male; donor 7 - 50 year old female; donor 8 - 48 year old female; donor 9 - 53 year old female; donor 10 - 23 year old female
Gene expression analyses reveal molecular relationships among 20 regions of the human CNS.
No sample metadata fields
View SamplesUsing fluorescence activated cell sorting, we isolated CD45+, CSF1R-GFP+, F4/80+, Ly6G- mouse lung monocytes and macrophages at 7 days after pneumonectomy procedure. We then used microfluidic single cell RNA-sequencing to transcriptional profile unique myeloid subsets. Using the pneumonectomy dataset, we identified 6 cell groups and 4 gene groups that marked several regenerative macrophage subsets including CCR2+, Ly6C+ monocytes and CD206+, Chil3+ M2-like macrophages. Overall design: individual macrophages 7 days post-pneumonectomy in a B6 CSF1R-GFP mouse
Recruited Monocytes and Type 2 Immunity Promote Lung Regeneration following Pneumonectomy.
Specimen part, Subject
View SamplesUsing fluorescence activated cell sorting, we isolated CD45+, CSF1R-GFP+, F4/80+, Ly6G- mouse lung monocytes and macrophages at 7 days after sham thoracotomy procedures. We then used microfluidic single cell RNA-sequencing to transcriptional profile unique myeloid subsets. Overall design: After sequencing 31 single cell transcriptomes were analyzed. Hierarcical and k-means clustering reveals several populations of macrophages are present in the lung.
Recruited Monocytes and Type 2 Immunity Promote Lung Regeneration following Pneumonectomy.
Specimen part, Subject
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