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:Synthetic selective thyroid hormone (TH) receptor (TR) modulators (STRMs) exhibit beneficial effects on dyslipidemias in animals and humans and reduce obesity, fatty liver and insulin resistance in preclinical animal models. STRMs differ from native THs in preferential binding to the TRβ subtype versus TRα, increased uptake into liver and reduced uptake into other tissues. However, selective modulators of other nuclear receptors (NRs) exhibit important gene-selective actions which have been attributed to differential effects on receptor conformation and dynamics and these effects can have profound influences in animals and humans. While there are suggestions that STRMs could exhibit such gene-specific actions, the extent to which these effects are actually observed in vivo has not been explored. Here, we show that saturating concentrations of the main active form of TH, triiodothyronine (T3), and the prototype STRM GC-1 induce identical gene-sets in livers of euthyroid and hypothyroid mice and a human cultured hepatoma cell line that only expresses TRβ, HepG2. We find one case in which GC-1 exhibits a modest gene-specific reduction in potency versus T3, at angiopoietin-like factor 4 (ANGPTL4) in HepG2. Investigation of the latter effect confirms that GC-1 acts through TRβ to directly induce this gene. However, this gene-selective GC-1 activity is not related to unusual T3 response element (TRE) sequence, unlike previously documented promoter-selective STRM actions. Together, our data suggest that T3 and GC-1 exhibit almost identical gene regulation properties and that gene-selective actions of GC-1 and similar STRMs will be subtle and rare. We treated HepG2 with vehicle or 10nM ligand (T3 or GC1; n=3 / treatment), analyzing mRNA 24h post treatment [Affymetrix]. We also treated 9-week old euthyroid male C57/Bl6 mice with vehicle or ligand (T3 or GC-1) by a single oral gavage (n=5 per treatment) and also performed a similar study in which mice were first made hypothyroid by two week feeding on iodine deficient diet (n=3-4 per treatment), analyzing mRNA 24h post treatment [Illumina].
Project description:Synthetic selective thyroid hormone (TH) receptor (TR) modulators (STRMs) exhibit beneficial effects on dyslipidemias in animals and humans and reduce obesity, fatty liver and insulin resistance in preclinical animal models. STRMs differ from native THs in preferential binding to the TR? subtype versus TR?, increased uptake into liver and reduced uptake into other tissues. However, selective modulators of other nuclear receptors (NRs) exhibit important gene-selective actions which have been attributed to differential effects on receptor conformation and dynamics and these effects can have profound influences in animals and humans. While there are suggestions that STRMs could exhibit such gene-specific actions, the extent to which these effects are actually observed in vivo has not been explored. Here, we show that saturating concentrations of the main active form of TH, triiodothyronine (T3), and the prototype STRM GC-1 induce identical gene-sets in livers of euthyroid and hypothyroid mice and a human cultured hepatoma cell line that only expresses TR?, HepG2. We find one case in which GC-1 exhibits a modest gene-specific reduction in potency versus T3, at angiopoietin-like factor 4 (ANGPTL4) in HepG2. Investigation of the latter effect confirms that GC-1 acts through TR? to directly induce this gene. However, this gene-selective GC-1 activity is not related to unusual T3 response element (TRE) sequence, unlike previously documented promoter-selective STRM actions. Together, our data suggest that T3 and GC-1 exhibit almost identical gene regulation properties and that gene-selective actions of GC-1 and similar STRMs will be subtle and rare. We treated 9-week old euthyroid male C57/Bl6 mice with vehicle or ligand (T3 or GC-1) by a single oral gavage (n=5 per treatment) and also performed a similar study in which mice were first made hypothyroid by two week feeding on iodine deficient diet (n=3-4 per treatment), analyzing mRNA 24h post treatment [Illumina]. We also treated HepG2 with vehicle or 10nM ligand (T3 or GC1; n=3 / treatment), analyzing mRNA 24h post treatment [Affymetrix].
Project description:Synthetic selective thyroid hormone (TH) receptor (TR) modulators (STRMs) exhibit beneficial effects on dyslipidemias in animals and humans and reduce obesity, fatty liver and insulin resistance in preclinical animal models. STRMs differ from native THs in preferential binding to the TRβ subtype versus TRα, increased uptake into liver and reduced uptake into other tissues. However, selective modulators of other nuclear receptors (NRs) exhibit important gene-selective actions which have been attributed to differential effects on receptor conformation and dynamics and these effects can have profound influences in animals and humans. While there are suggestions that STRMs could exhibit such gene-specific actions, the extent to which these effects are actually observed in vivo has not been explored. Here, we show that saturating concentrations of the main active form of TH, triiodothyronine (T3), and the prototype STRM GC-1 induce identical gene-sets in livers of euthyroid and hypothyroid mice and a human cultured hepatoma cell line that only expresses TRβ, HepG2. We find one case in which GC-1 exhibits a modest gene-specific reduction in potency versus T3, at angiopoietin-like factor 4 (ANGPTL4) in HepG2. Investigation of the latter effect confirms that GC-1 acts through TRβ to directly induce this gene. However, this gene-selective GC-1 activity is not related to unusual T3 response element (TRE) sequence, unlike previously documented promoter-selective STRM actions. Together, our data suggest that T3 and GC-1 exhibit almost identical gene regulation properties and that gene-selective actions of GC-1 and similar STRMs will be subtle and rare.
Project description:Synthetic selective thyroid hormone (TH) receptor (TR) modulators (STRMs) exhibit beneficial effects on dyslipidemias in animals and humans and reduce obesity, fatty liver and insulin resistance in preclinical animal models. STRMs differ from native THs in preferential binding to the TRβ subtype versus TRα, increased uptake into liver and reduced uptake into other tissues. However, selective modulators of other nuclear receptors (NRs) exhibit important gene-selective actions which have been attributed to differential effects on receptor conformation and dynamics and these effects can have profound influences in animals and humans. While there are suggestions that STRMs could exhibit such gene-specific actions, the extent to which these effects are actually observed in vivo has not been explored. Here, we show that saturating concentrations of the main active form of TH, triiodothyronine (T3), and the prototype STRM GC-1 induce identical gene-sets in livers of euthyroid and hypothyroid mice and a human cultured hepatoma cell line that only expresses TRβ, HepG2. We find one case in which GC-1 exhibits a modest gene-specific reduction in potency versus T3, at angiopoietin-like factor 4 (ANGPTL4) in HepG2. Investigation of the latter effect confirms that GC-1 acts through TRβ to directly induce this gene. However, this gene-selective GC-1 activity is not related to unusual T3 response element (TRE) sequence, unlike previously documented promoter-selective STRM actions. Together, our data suggest that T3 and GC-1 exhibit almost identical gene regulation properties and that gene-selective actions of GC-1 and similar STRMs will be subtle and rare.
Project description:Thyroid hormone (TH) secreted by the thyroid gland plays essential roles in regulating metabolism, development, and nervous system function. Thyroid hormone receptor-associated protein 3 (THRAP3) is a nuclear coactivator that interacts with the thyroid hormone receptor (TR) and facilitates target gene regulation through the mediator complex. Although this mechanism has been well studied in other tissues, the specific role of THRAP3 in skeletal muscle remains unclear. Here we investigated the function of THRAP3 in skeletal muscle using Thrap3 knockout (KO) C2C12 cells. Loss of THRAP3 significantly suppressed the expression of key myogenic regulatory factors, including Myod1, Mef2c, and myosin heavy chain genes, resulting in impaired myogenic differentiation and muscle diameter. Furthermore, we found that THRAP3 influences triiodothyronine (T3)-induced gene expression, suggesting that it cooperatively modulates thyroid hormone signaling in muscle cells. Taken together, our findings identify THRAP3 as a novel regulator of myogenesis and indicate that it supports T3 activity by coordinating thyroid hormone–responsive gene expression in skeletal muscle.
Project description:Microarray study of iBAT gene expression comparing a) adult male offspring of control and 3,3’,5-triiodothyronine (T3)-treated mothers during pregnancy and b) adult male offspring of control and maternal thyroid hormone receptor (TR) β signaling (TRb) treated mothers during pregnancy. Microarrays were conducted by Atlas Biolabs (Berlin, Germany) on GeneChip Clariom S arrays (Affymetrix/Thermofisher, Germany).
Project description:Thyroid hormone (3,5,3'-triiodothyronine, T3) sensitively influences the pituitary gland, a source of hormones that control tissues throughout the body. The underlying transcriptional response is believed to hinge crucially on interaction of T3 receptors with enhancers in the genome but it remains unknown how T3 regulates pituitary chromatin and how this regulation adjusts to hypothyroid and hyperthyroid conditions.