Project description:The nuclear factor erythroid 2-related factor 2 (NRF2) transcription factor activates cytoprotective and metabolic gene expression in response to various electrophilic stressors. In disease, constitutive NRF2 activity promotes cancer progression while decreased NRF2 function contributes to neurodegenerative diseases. In contrast to the regulation of NRF2 protein stability in the cytoplasm, co-complexed proteins that govern NRF2 activity on chromatin are less clear. Using biotin proximity proteomics, we report networks for NRF2 and its family members NRF1, NRF3 and the NRF2 heterodimer MAFG. We found that the Parkinson’s disease zinc finger transcription factor ZNF746 (PARIS) physically associated with NRF2 and MAFG, resulting in suppression of NRF2-driven transcription. ZNF746 expression increased oxidative stress and apoptosis, phenotypes that were reversed by chemical and genetic hyperactivation of NRF2. This study presents a functionally annotated proximity network for NRF2 and suggests that ZNF746 overexpression in Parkinson’s disease directly inhibits NRF2-driven neuroprotection
Project description:The nuclear factor erythroid 2-related factor 2 (NRF2) transcription factor activates cytoprotective and metabolic gene expression in response to various electrophilic stressors. In disease, constitutive NRF2 activity promotes cancer progression while decreased NRF2 function contributes to neurodegenerative diseases. In contrast to the regulation of NRF2 protein stability in the cytoplasm, co-complexed proteins that govern NRF2 activity on chromatin are less clear. Using biotin proximity proteomics, we report networks for NRF2 and its family members NRF1, NRF3 and the NRF2 heterodimer MAFG. We found that the Parkinson’s disease zinc finger transcription factor ZNF746 (PARIS) physically associated with NRF2 and MAFG, resulting in suppression of NRF2-driven transcription. ZNF746 expression increased oxidative stress and apoptosis, phenotypes that were reversed by chemical and genetic hyperactivation of NRF2. This study presents a functionally annotated proximity network for NRF2 and suggests that ZNF746 overexpression in Parkinson’s disease directly inhibits NRF2-driven neuroprotection.
Project description:The Nrf2 transcription factor is a key player in the cellular stress response, which regulates the expression of important antioxidant enzymes and other cytoprotective proteins. We recently generated a novel transgenic mouse model to determine the function of Nrf2 in the skin. These mice show reduced number of apoptotic keratinocytes after UVB irradiation due to enhanced ROS detoxification. They also show enhanced tumorigenesis in the HPV8 tumor model. RNA from whole skin of 3 single P2.5 K5cre-caNrf2 (tg/tg) and 3 single P2.5 K5cre-wt (tg/wt=control) mice were used
Project description:The Nrf2 transcription factor is a key player in the cellular stress response, which regulates the expression of important antioxidant enzymes and other cytoprotective proteins. We recently generated a novel transgenic mouse model to determine the function of Nrf2 in the skin. These mice revealed interesting phenotypic abnormalities, including hyperkeratosis and acanthosis. To gain insight into the underlying molecular mechanisms, we wanted to identify genes, which are differentially expressed in the skin of wild-type and mutant mice before the onset of phenotypic abnormalities. RNA from whole skin of 3 single P2.5 K5cre-caNrf2 (tg/tg) and 3 single P2.5 K5cre-wt (tg/wt=control) mice were used
Project description:The Nrf2 transcription factor is a key player in the cellular stress response, which regulates the expression of important antioxidant enzymes and other cytoprotective proteins. We recently generated a novel transgenic mouse model to determine the function of Nrf2 in the skin. These mice show reduced number of apoptotic keratinocytes after UVB irradiation due to enhanced ROS detoxification. They also show enhanced tumorigenesis in the HPV8 tumor model.
Project description:The Nrf2 transcription factor is a key player in the cellular stress response, which regulates the expression of important antioxidant enzymes and other cytoprotective proteins. We recently generated a novel transgenic mouse model to determine the function of Nrf2 in the skin. These mice revealed interesting phenotypic abnormalities, including hyperkeratosis and acanthosis. To gain insight into the underlying molecular mechanisms, we wanted to identify genes, which are differentially expressed in the skin of wild-type and mutant mice before the onset of phenotypic abnormalities.
Project description:Background: Nrf2 is an essential cytoprotective transcription factor. However, association of Nrf2 in organ development and neonatal disease is rarely examined. Hyperoxia exposure to newborn rodents generates pulmonary phenotypes which resemble bronchopulmonary dysplasia (BPD) of prematurity. Methods: To investigate the role of Nrf2 in lung maturation and BPD pathogenesis, Nrf2-deficient (Nrf2-/-) and wild-type (Nrf2+/+) neonates were exposed to air or hyperoxia (O2). Transcriptome analysis determined Nrf2-directed mechanisms in premature lung. Lung injury was assessed by bronchoalveolar lavage analysis and histopathology. Results: In Nrf2-/- neonates, basal expression of cell cycle machinery, redox balance, and lipid/carbohydrate metabolism genes were suppressed while immunity genes were overexpressed compared to Nrf2+/+ pups. O2-induced mortality and pulmonary inflammation/injury were significantly higher in Nrf2-/- than in Nrf2+/+. Lung DNA lesion and oxidation were greater in Nrf2-/- than in Nrf2+/+, constitutively and after O2. Nrf2-dependent genes modulated cellular growth/proliferation, defense, immunity, and lipid metabolism against hyperoxia. Bioinformatic elucidation of Nrf2 binding motifs and augmented O2-induced inflammation in genetically deficient neonates validated Gpx2 and Marco as Nrf2 effectors. Conclusion: Overall, Nrf2 in underdeveloped lungs orchestrated cell cycle, morphogenesis, and immunity as well as cellular defense constitutively and under oxidant stress. Results provide putative molecular mechanisms of Nrf2-directed lung alveolarization and BPD of prematurity. PARALLEL study design with 42 samples comparing 14 groups of age (P1 to P4 corresponding to day 0 to day 3 animals), gene, and exposure: (4 groups Nrf+/+ wild type P1-P4 air exposure) (4 groups Nrf -/- knockout P1-P4 air exposure), (3 groups Nrf+/+ wild type P2-P4 with 100 percent O2 (hyperoxia exposure) and 3 groupsNrf -/- knockout P2-P4 with 100 percent O2 (hyperoxia exposure)) Biological replicates: 3 per group
Project description:Background: Nrf2 is an essential cytoprotective transcription factor. However, association of Nrf2 in organ development and neonatal disease is rarely examined. Hyperoxia exposure to newborn rodents generates pulmonary phenotypes which resemble bronchopulmonary dysplasia (BPD) of prematurity. Methods: To investigate the role of Nrf2 in lung maturation and BPD pathogenesis, Nrf2-deficient (Nrf2-/-) and wild-type (Nrf2+/+) neonates were exposed to air or hyperoxia (O2). Transcriptome analysis determined Nrf2-directed mechanisms in premature lung. Lung injury was assessed by bronchoalveolar lavage analysis and histopathology. Results: In Nrf2-/- neonates, basal expression of cell cycle machinery, redox balance, and lipid/carbohydrate metabolism genes were suppressed while immunity genes were overexpressed compared to Nrf2+/+ pups. O2-induced mortality and pulmonary inflammation/injury were significantly higher in Nrf2-/- than in Nrf2+/+. Lung DNA lesion and oxidation were greater in Nrf2-/- than in Nrf2+/+, constitutively and after O2. Nrf2-dependent genes modulated cellular growth/proliferation, defense, immunity, and lipid metabolism against hyperoxia. Bioinformatic elucidation of Nrf2 binding motifs and augmented O2-induced inflammation in genetically deficient neonates validated Gpx2 and Marco as Nrf2 effectors. Conclusion: Overall, Nrf2 in underdeveloped lungs orchestrated cell cycle, morphogenesis, and immunity as well as cellular defense constitutively and under oxidant stress. Results provide putative molecular mechanisms of Nrf2-directed lung alveolarization and BPD of prematurity.
Project description:Arp2/3 complex assembles branched actin filaments key to many cellular processes, but its organismal roles remain poorly understood. Here we employed conditional arpc4 knockout mice to study the function of the Arp2/3 complex in the epidermis.We found that depletion of the Arp2/3 complex by knockout of arpc4 results in skin abnormalities at birth that evolve into a severe psoriasis-like disease hallmarked by hyperactivation of transcription factor Nrf2. Knockout of arpc4 in cultured keratinocytes was sufficient to induce nuclear accumulation of Nrf2, upregulation of Nrf2-target genes and decreased filamentous actin levels. Furthermore, pharmacological inhibition of the Arp2/3 complex unmasked the role of branched actin filaments in Nrf2 regulation. Consistently, we unveiled that Nrf2 associates with the actin cytoskeleton in cells and binds to filamentous actin in vitro Finally, we discovered that Arpc4 is downregulated in both human and mouse psoriatic epidermis. Thus, the Arp2/3 complex affects keratinocytes' shape and transcriptome through an actin-based cell-autonomous mechanism that influences epidermal morphogenesis and homeostasis.