ABSTRACT: 21 samples of liver RNA coming from mice treated with glucagon (Gluc), thyroid hormone (T3), both, or the conjugated compound (Cp). Each sample comes from a single mice.
Project description:This SuperSeries is composed of the following subset Series: GSE32443: Identical gene regulation patterns of triiodothyronine (T3) and selective thyroid hormone receptor modulator GC-1 [Affymetrix] GSE32444: Identical gene regulation patterns of triiodothyronine (T3) and selective thyroid hormone receptor modulator GC-1 [Illumina] Refer to individual Series
Project description:Thyroid hormone (T3) and high glucose concentrations are critical components of β-cell maturation and function. In the present study, we asked whether T3 and glucose signaling pathways coordinately regulate transcription of genes important for β-cell function and proliferation
Project description:The v-erbA oncogene belongs to a superfamily of transcription factors called nuclear receptors, which includes the thyroid hormone receptors (TRs) responsible for mediating the effects of thyroid hormone (T3). Nuclear receptors bind to specific DNA sequences in the promoter region of target genes and v-erbA is known to exert a dominant negative effect on the activity of the TRs. The repressor activity of v-erbA has been linked to the development of hepatocellular carcinoma (HCC) in a mouse model. We have used microarray analysis to identify genes differentially expressed in hepatocytes in culture (AML12 cells) stably transfected with v-erbA and exposed to T3. We have found that v-erbA can negatively regulate expression of T3-responsive genes known to have a protective function against tumor development. We have also identified a number of v-erbA- (but not T3-) responsive genes that are known to be involved in carcinogenesis and which may play a role in the development of HCC.
Project description:We used an integrated genomics approach to profile and characterize the cistrome of TR-beta, map changes in chromatin accessibility, and capture the transcriptomic changes in response to T3 in a normal thyroid cell line. Our data demonstrates that T3 promotes significant shifts in TR-beta genomic occupancy, which are associated with differential chromatin accessibility, and differential recruitment of SWI/SNF chromatin remodelers.
Project description:We used an integrated genomics approach to profile and characterize the cistrome of TR-beta, map changes in chromatin accessibility, and capture the transcriptomic changes in response to T3 in a normal thyroid cell line. Our data demonstrates that T3 promotes significant shifts in TR-beta genomic occupancy, which are associated with differential chromatin accessibility, and differential recruitment of SWI/SNF chromatin remodelers.
Project description:We used an integrated genomics approach to profile and characterize the cistrome of TR-beta, map changes in chromatin accessibility, and capture the transcriptomic changes in response to T3 in a normal thyroid cell line. Our data demonstrates that T3 promotes significant shifts in TR-beta genomic occupancy, which are associated with differential chromatin accessibility, and differential recruitment of SWI/SNF chromatin remodelers.
Project description:Thyroid hormone (TH) influences metabolic pathways by binding to specific receptors (TRs), which are conditional transcription factors. T3 works through TRs to induce fibroblast growth factor (FGF) 21, a peptide hormone that is usually induced in fasting and influences lipid and carbohydrate metabolism via local hepatic and systemic endocrine effects. While administered TH and FGF21 display overlapping actions, including reductions in serum lipids, current models suggest that these hormones act independently in vivo. Here, we examined mechanisms of TH regulation of FGF21 expression and tested the possibility that FGF21 is required for induction of hepatic TH-responsive genes. We confirm that active TH (T3) and the TRβ selective thyromimetic GC-1 increase FGF21 transcript and peptide levels in mouse liver and that this effect requires TRβ. T3 also induces FGF21 in cultured hepatocytes and this effect involves direct actions of TRβ1, which binds a TRE within intron 2 of FGF21. Gene expression profiles in wild type and FGF21 knockout mice are highly similar indicating that FGF21 is dispensable for the majority of hepatic T3 gene responses. A small subset of genes displays diminished T3 response in the absence of FGF21. However, most of these are not obviously involved in T3-dependent hepatic lipid and carbohydrate metabolic processes. Accordingly, T3-dependent effects upon serum lipids are maintained in the FGF21-/- background. Our findings suggest that T3 regulates genes involved in classical hepatic metabolic responses independently of FGF21.
Project description:Tagged versions of thyroid hormone receptors alpha (TRa) and beta (TRb) were stably transfected in two C17.2 cell lines, C17.2a and C17.2b, respectively. Cells were treated with 10-7 M T3 for 6, 12 or 24h or left untreated. We performed DGE by sequencing all polyA RNA according to a SAGE-derived method. Differential gene expression after T3 treatment was computed and the T3 responses induced by the two receptors were compared. We could conclude that, in a similar environment, target genes are only partially shared and that a significant proportion show receptor preference and even selectivity. Examination of thyroid hormone target genes over time in two cell lines (C17.2a, C17.2b), each expressing one of the thyroid hormone receptors (alpha, beta).