Project description:We identify differentially expressed inducible genes in activated B cells harvested from mice lacking expression of the orphan nuclear hormone receptor Nr4a1.
Project description:NR4A1 (Nur77, TR3) is an orphan nuclear receptor that is overexpressed in pancreatic cancer cells and tumors and exhibits pro-oncogenic activity. Knockdown of NR4A1 by RNA interference (siNR4A1) in Panc1 cells and analysis of the proteome resulted in induction of several markers of endoplasmic reticulum (ER) stress including glucose-related protein 78 (GRP78), CCAAT/enhancer-binding protein-homologous protein (CHOP), activating transcription factor-3 (ATF-3) and AFT-6. These effects were accompanied by induction of apoptosis and similar results were observed after treatment of pancreatic cancer cells with the known inactivator of NR4A1, 1,1-bis(3’-indolyl)-1-(p-hydroxyphenyl)methane (DIM-C-pPhOH). Both siNR4A1 (transfected) and DIM-C-pPhOH also induced reactive oxygen species (ROS) and induction of ROS and ER stress by these agents was attenuated after cotreatment with antioxidants. Transfection of Panc1 cells with siNR4A1 follow by analysis of gene expression by arrays identified ROS metabolism genes regulated by NR4A1. Knockdown of one of these genes, thioredoxin domain containing 5 (TXNDC5) also resulted in induction of ROS and ER stress demonstrating that NR4A1 regulates levels of ER stress and ROS in pancreatic cancer cells to facilitate cell proliferation and survival. Inactivation of this receptor by siNR4A1 or DIM-C-pPhOH decreases TXNDC5 resulting in activation of ROS/ER stress and pro-apoptotic pathways and represents a novel pathway for inducing cell death in pancreatic cancer cells. Two groups of samples are included: 1. siControl; 2. siNR4A1 treatment in PAC1 cell. Transfection of Panc1 cells with siNR4A1 follow by analysis of gene expression by arrays identified ROS metabolism genes regulated by NR4A1.
Project description:The nuclear orphan receptor Nur77 (NR4A1, TR3, or NGFI-B) has been shown to exhibit an anti-inflammatory function in macrophages. To further elucidate the role of Nur77 in macrophage physiology, we compared the transcriptome of bone marrow-derived macrophages (BMM) from wild-type (WT) and Nur77-knockout (KO) mice both before and after stimulation with IL4 or LPS. Comparison of gene expression in bone marrow-derived macrophages, isolated from 3 wild-type (control) and 3 Nur77-/- mice (case), left untreated or stimulated in triplicate for 8 hours with LPS or IL-4
Project description:NR4A1 (Nur77, TR3) is an orphan nuclear receptor that is overexpressed in pancreatic cancer cells and tumors and exhibits pro-oncogenic activity. Knockdown of NR4A1 by RNA interference (siNR4A1) in Panc1 cells and analysis of the proteome resulted in induction of several markers of endoplasmic reticulum (ER) stress including glucose-related protein 78 (GRP78), CCAAT/enhancer-binding protein-homologous protein (CHOP), activating transcription factor-3 (ATF-3) and AFT-6. These effects were accompanied by induction of apoptosis and similar results were observed after treatment of pancreatic cancer cells with the known inactivator of NR4A1, 1,1-bis(3’-indolyl)-1-(p-hydroxyphenyl)methane (DIM-C-pPhOH). Both siNR4A1 (transfected) and DIM-C-pPhOH also induced reactive oxygen species (ROS) and induction of ROS and ER stress by these agents was attenuated after cotreatment with antioxidants. Transfection of Panc1 cells with siNR4A1 follow by analysis of gene expression by arrays identified ROS metabolism genes regulated by NR4A1. Knockdown of one of these genes, thioredoxin domain containing 5 (TXNDC5) also resulted in induction of ROS and ER stress demonstrating that NR4A1 regulates levels of ER stress and ROS in pancreatic cancer cells to facilitate cell proliferation and survival. Inactivation of this receptor by siNR4A1 or DIM-C-pPhOH decreases TXNDC5 resulting in activation of ROS/ER stress and pro-apoptotic pathways and represents a novel pathway for inducing cell death in pancreatic cancer cells.
Project description:The nuclear orphan receptor Nur77 (NR4A1, TR3, or NGFI-B) has been shown to exhibit an anti-inflammatory function in macrophages. To further elucidate the role of Nur77 in macrophage physiology, we compared the transcriptome of bone marrow-derived macrophages (BMM) from wild-type (WT) and Nur77-knockout (KO) mice both before and after stimulation with IL4 or LPS.
Project description:Manufactured nanomaterials (MNMs) are increasingly incorporated into consumer products that are disposed into sewage. In wastewater treatment, MNMs adsorb to activated sludge biomass where they may impact biological wastewater treatment performance, including nutrient removal. Here, we studied MNM effects on bacterial polyhydroxyalkanoate (PHA), specifically polyhydroxybutyrate (PHB), biosynthesis because of its importance to enhanced biological phosphorus (P) removal (EBPR). Activated sludge was sampled from an anoxic selector of a municipal wastewater treatment plant (WWTP), and PHB-containing bacteria were concentrated by density gradient centrifugation. After starvation to decrease intracellular PHB stores, bacteria were nutritionally augmented to promote PHB biosynthesis while being exposed to either MNMs (TiO2 or Ag) or to Ag salts (each at a concentration of 5 mg L-1). Cellular PHB concentration and PhyloChip community composition were analyzed. The final bacterial community composition differed from activated sludge, demonstrating that laboratory enrichment was selective. Still, PHB was synthesized to near-activated sludge levels. Ag salts altered final bacterial communities, although MNMs did not. PHB biosynthesis was diminished with Ag (salt or MNMs), indicating the potential for Ag-MNMs to physiologically impact EBPR through the effects of dissolved Ag ions on PHB producers. 18 samples; Triplicate PHB-enriched bacterial communities recovered from activated sludge were exposed to nanoparticle (TiO2 or Ag) or AgNO3 (as a silver control) or were not exposed to an nanoparticles (control) to determine if the naoparticles affected PHB production.
Project description:Manufactured nanomaterials (MNMs) are increasingly incorporated into consumer products that are disposed into sewage. In wastewater treatment, MNMs adsorb to activated sludge biomass where they may impact biological wastewater treatment performance, including nutrient removal. Here, we studied MNM effects on bacterial polyhydroxyalkanoate (PHA), specifically polyhydroxybutyrate (PHB), biosynthesis because of its importance to enhanced biological phosphorus (P) removal (EBPR). Activated sludge was sampled from an anoxic selector of a municipal wastewater treatment plant (WWTP), and PHB-containing bacteria were concentrated by density gradient centrifugation. After starvation to decrease intracellular PHB stores, bacteria were nutritionally augmented to promote PHB biosynthesis while being exposed to either MNMs (TiO2 or Ag) or to Ag salts (each at a concentration of 5 mg L-1). Cellular PHB concentration and PhyloChip community composition were analyzed. The final bacterial community composition differed from activated sludge, demonstrating that laboratory enrichment was selective. Still, PHB was synthesized to near-activated sludge levels. Ag salts altered final bacterial communities, although MNMs did not. PHB biosynthesis was diminished with Ag (salt or MNMs), indicating the potential for Ag-MNMs to physiologically impact EBPR through the effects of dissolved Ag ions on PHB producers.
Project description:Nur77 is an orphan member of the nuclear receptor superfamily that is expressed in various types of cells and mediates diverse biological processes. The knock out Nur77 has a mutation in exon 2. Ligands of the nuclear receptor are unknown. Keywords: Dual colour hybridisation on cDNA microarrays, Nur77, Knock out
Project description:Vascular permeability is frequently associated with inflammation and it is triggered by chemokines and by a cohort of secreted permeability factors, such as VEGF. In contrast, here we showed that the physiological vascular permeability that precedes implantation is directly controlled by progesterone receptor (PR) and it is independent of VEGF. Both global and endothelial-specific deletion of PR block physiological vascular permeability in the uterus while misexpression of PR in the endothelium of other organs results in ectopic vascular leakage. Integration of genome-wide transcriptional profile of endothelium and ChIP-sequencing revealed that PR induces a NR4A1 (Nur77/TR3) specific transcriptional program that broadly regulates vascular permeability in response to progesterone. This program triggers concurrent suppression of several junctional proteins and leads to an effective, timely and venule-specific regulation of vascular barrier function. Silencing NR4A1 blocks PR-mediated permeability responses indicating a direct link between PR and NR4A1. These results reveal a previously unknown function for progesterone receptor on endothelial cell biology with consequences to physiological vascular permeability and implications to the clinical use of progestins and anti-progestins on blood vessel integrity. Examination of PR binding sites in HUVEC cells using ChIP-seq (non-infected-negative control, PR infected followed by ligand treatment-PR+P or vehicle PR)
Project description:Vascular permeability is frequently associated with inflammation and it is triggered by chemokines and by a cohort of secreted permeability factors, such as VEGF. In contrast, here we showed that the physiological vascular permeability that precedes implantation is directly controlled by progesterone receptor (PR) and it is independent of VEGF. Both global and endothelial-specific deletion of PR block physiological vascular permeability in the uterus while misexpression of PR in the endothelium of other organs results in ectopic vascular leakage. Integration of genome-wide transcriptional profile of endothelium and ChIP-sequencing revealed that PR induces a NR4A1 (Nur77/TR3) specific transcriptional program that broadly regulates vascular permeability in response to progesterone. This program triggers concurrent suppression of several junctional proteins and leads to an effective, timely and venule-specific regulation of vascular barrier function. Silencing NR4A1 blocks PR-mediated permeability responses indicating a direct link between PR and NR4A1. These results reveal a previously unknown function for progesterone receptor on endothelial cell biology with consequences to physiological vascular permeability and implications to the clinical use of progestins and anti-progestins on blood vessel integrity. Examination of PR target genes in human umbilical vein endothelial cells (HUVECs) using RNA-seq (PR infected only -PR only and PR infected followed by ligand treatment-PR+P)