We assessed the impact of glucose transporter Glut2 gene inactivation in adult mouse liver (LG2KO mice). This suppressed hepatic glucose uptake but not glucose output. In the fasted state, expression of carbohydrate responsive element-binding protein (ChREBP) and its glycolytic and lipogenic target genes was abnormally elevated. Feeding, energy expenditure, and insulin sensitivity were identical in LG2KO and control mice. Glucose tolerance was normal early after Glut2 inactivation but intolerance developed at later time. This was caused by progressive impairment of glucose-stimulated insulin secretion even though beta-cell mass and insulin content remained normal. Liver transcript profiling revealed a coordinate down-regulation of cholesterol biosynthesis genes in LG2KO mice. This was associated with reduced hepatic cholesterol in fasted mice and a 30 percent reduction in bile acid production. We showed that chronic bile acids or FXR agonist treatment of primary islets increases glucose-stimulated insulin secretion, an effect not seen in islets from fxr-/- mice. Collectively, our data show that glucose sensing by the liver controls beta-cell glucose competence, through a mechanism that likely depends on bile acid production and action on beta-cells.
Hepatic glucose sensing is required to preserve β cell glucose competence.
Specimen part
View SamplesWe examined global gene expression patterns in response to PGC-1 expression in cells derived from liver or muscle.
Direct link between metabolic regulation and the heat-shock response through the transcriptional regulator PGC-1α.
Specimen part
View SamplesCell adhesion plays an important role in determining cell shape and function in a variety of physiological and pathophysiological conditions. While links between metabolism and cell adhesion were previously suggested, the exact context and molecular details of such a cross-talk remain incompletely understood.
Inhibition of Adhesion Molecule Gene Expression and Cell Adhesion by the Metabolic Regulator PGC-1α.
Specimen part, Cell line
View SamplesSecreted proteins serve pivotal roles in the development of multicellular organisms, acting as structural matrix, extracellular enzymes and signal molecules. In this study we demonstrate, unexpectedly, that PGC-1, a critical transcriptional co-activator of metabolic gene expression, functions to down-regulate expression of diverse genes encoding secreted molecules and extracellular matrix (ECM) components to modulate the secretome. We show that both endogenous and exogenous PGC-1 down-regulate expression of numerous genes encoding secreted molecules. Mechanistically, results obtained using mRNA stability measurements as well as intronic RNA expression analysis are consistent with a transcriptional effect of PGC-1 on expression of genes encoding secreted proteins. Interestingly, PGC-1 requires the central heat shock response regulator HSF1 to affect some of its targets, and both factors co-reside on several target genes encoding secreted molecules in cells. Finally, using a mass spectrometric analysis of secreted proteins, we demonstrate that PGC-1 modulates the secretome of mouse embryonic fibroblasts (MEFs).
Control of Secreted Protein Gene Expression and the Mammalian Secretome by the Metabolic Regulator PGC-1α.
Specimen part
View SamplesPurpose: The objective of this study was to determine cardiac transcriptional pathways regulated in response to 1.) hypothyroidism and re-establishment of a euthyroid state and 2.) Med13-dependent cardiac transcriptional pathways regulated in response to hypothyroidism and re-establishment of a euthyroid state Overall design: Methods: WT and Med13 cardiac-specific knockout mice (Med13cKO) were put on a normal chow or PTU diet at 8 weeks of age for a duration of 4 weeks. A third group was put on a PTU diet for 4 weeks followed by 3 daily injections of T3.
Regulation of cardiac transcription by thyroid hormone and Med13.
No sample metadata fields
View SamplesAnalysis of gene expression profile of LSK (Lin-Sca-1+ c-Kit+) isolated from Jmjd1c f/f Vav1Cre or Vav1Cre controls. Loss of Jmjd1c minimally affected HSC in homeostatsis while impiars HSC function in response to stree such as transplantation and 5-Fu treatment. These results provide insight into the role of Jmjd1c in normal hematopoiesis. Overall design: LSK cells were isolated from bone marrow of seven weeks old Jmjd1c f/f Vav1Cre or Vav1Cre controls mice by flow acivated cell sorting and subjected to RNA-seq.
MLL-AF9- and HOXA9-mediated acute myeloid leukemia stem cell self-renewal requires JMJD1C.
Specimen part, Cell line, Subject
View SamplesAnalysis of gene expression profile of Hoxa9/Meis1 leukemia cells 6 days after loss of Jmjd1c. Loss of Jmjd1c induces differentiation and Hoxa9/Meis1 leukemia cells. These results provide insight into the role of Jmjd1c in AML with elelvated expression of Hoxa9. Overall design: We used primary Jmjd1c f/f Hoxa9/Meis1 neo leukemia cells from three leukemic mice and delivered Cre-Tomato by retroviral infection. We sorted Tomato positive cells 6 days after Cre infection and subjected the samples to RNA-seq.
MLL-AF9- and HOXA9-mediated acute myeloid leukemia stem cell self-renewal requires JMJD1C.
Specimen part, Cell line, Subject
View SamplesPrevious results suggest that Bmh might inhibit the activity of the transcription factor Adr1 after binding to Adr1-dependent promoters. In a strain lacking the two major histone deacetylases, Hda1 and Rpd3 (hdac), Adr1 is bound to its target promoters recruiting what appears to be an inactive RNA ploymerase II preinitiation complex (PIC). To determine whether Bmh activity inhibits this inactive PIC and the generality of this effect on glucose-repressed gene expression, the mRNA profiles of wild type, bmh mutant, hdac mutant, and bmh hdac mutant cells grown in high glucose medium were compared.
14-3-3 (Bmh) proteins regulate combinatorial transcription following RNA polymerase II recruitment by binding at Adr1-dependent promoters in Saccharomyces cerevisiae.
No sample metadata fields
View SamplesThe white adipose tissue (WAT) rapidly loses mass when mice are fed a diet containing trans-10, cis-12 conjugated linoleic acid (t10c12 CLA). A microarray analysis of WAT due to CLA feeding was performed to better define the processes and genes involved. WAT weight decreased by ca. 80% over 17 days of feeding a 0.5% t10c12 CLA diet. The lipid volume decreased by 90% and the number of adipocytes and total cells were reduced by15% and 47%, respectively. Microarray profiling of replicated pools of control and treated mice (n=140) at seven time points over the 17day feeding indicated between 2798 to 4318 genes showed mRNA changes of 2-fold or more. Transcript levels for genes of glucose and fatty acid import or biosynthesis were significantly reduced. A prolific inflammation response was indicated by the 2 to100-fold induction of many cytokine transcripts, including those for IL-6, IL1?, TNF ligands, and CXC family members
Trans-10, cis-12 conjugated linoleic acid causes inflammation and delipidation of white adipose tissue in mice: a microarray and histological analysis.
Age
View SamplesWe are studying signaling pathways and growth properties of cultured human ovarian cancer cells that are expressing the G protein-coupled receptor, luteinizing hormone receptor (LHR),particularly interested in the changes that occur when the receptor is activated by its cognate ligand, gonadotropin (LH). To investigate these questions, we have employed the SKOV3 ovarian cancer cell line that has been stably transfected with LHR, and can then test the response of these cells in culture following exposure to LH.
Regulation of gene expression in ovarian cancer cells by luteinizing hormone receptor expression and activation.
Cell line, Treatment, Time
View Samples