Activation of nuclear orphan receptor NURR1 transcription by NF-kappa B and cyclic adenosine 5'-monophosphate response element-binding protein in rheumatoid arthritis synovial tissue.
McEvoy AN, Murphy EA, Ponnio T, Conneely OM, Bresnihan B, FitzGerald O, Murphy EP
In rheumatoid arthritis, inflammatory signals boost the NURR1 protein, which may help control joint inflammation. NURR1 is turned on by two key pathways—NF-kappaB and CREB—activated by common inflammatory chemicals like TNF-alpha and PGE2.
- NURR1 levels are high in rheumatoid arthritis joints
- Inflammation boosts NURR1 via NF-kappaB and CREB
- TNF-alpha and PGE2 trigger NURR1 production
- NURR1 may be a central switch for inflammation
- This suggests possible new treatment targets
Early induction of nerve growth factor-induced genes after liver resection-reperfusion injury.
Ohkubo T, Sugawara Y, Sasaki K, Maruyama K, Ohkura N, Makuuchi M
The NGFI-B family of genes, including NR4A2 (Nurr1), is rapidly activated in liver cells after injury from reduced blood flow and restored circulation. This activation is linked to a signaling pathway involving CREB, which may help regulate liver repair.
- NR4A2 (Nurr1) genes turn on within 30 minutes after liver injury
- The CREB protein binds to NR4A2 genes after injury
- This response happens in both rats and humans
- The pathway may help the liver regenerate after damage
Generation of tyrosine hydroxylase-immunoreactive neurons in ventral mesencephalic tissue of Nurr1 deficient mice.
Tornqvist N, Hermanson E, Perlmann T, Stromberg I
This study shows that Nurr1-deficient mouse brain tissue can still produce dopamine-producing neurons when grown in specific laboratory conditions with support from wild-type tissue. However, these neurons fail to form proper nerve fiber bundles and do not develop without additional growth factors or supportive tissue. This suggests that while the gene is not strictly required for neuron creation in a dish, it remains essential for normal structural development.
- Nurr1-deficient mouse tissue produces dopamine neurons when co-cultured with wild-type striatum.
- Neurons lack proper nerve fiber bundles without supportive wild-type tissue environment.
- Growth factors EGF and FGF-8 cannot rescue neuron formation in isolated knockout cultures.
- Results indicate Nurr1 is not required for initial dopamine neuron generation in vitro.
Retinoic acid prevents experimental Cushing syndrome.
Páez-Pereda M, Kovalovsky D, Hopfner U, Theodoropoulou M, Pagotto U, Uhl E, Losa M, Stalla J, Grübler Y, Missale C, Arzt E, Stalla GK
Retinoic acid reduces ACTH and cortisol production while killing tumor cells in mouse models of Cushing syndrome. This effect relies on the absence of the COUP-TFI protein, which is missing in these tumors but present in normal tissue.
- Retinoic acid lowers ACTH and cortisol levels in experimental Cushing syndrome mice.
- The treatment kills ACTH-secreting tumor cells without harming normal cells.
- COUP-TFI protein blocks retinoic acid's effect, explaining its selectivity for tumors.
Silencing mediator of retinoid and thyroid hormone receptors and activating signal cointegrator-2 as transcriptional coregulators of the orphan nuclear receptor Nur77.
Sohn YC, Kwak E, Na Y, Lee JW, Lee SK
This study identifies two proteins that regulate the activity of Nur77 (NR4A2) in laboratory cell cultures. It demonstrates that one protein enhances NR4A2 function while another suppresses it, though the exact mechanism of suppression does not involve standard histone modification pathways.
- SMRT and ASC-2 act as corepressors and coactivators for Nur77 respectively.
- Nur77 interacts directly with SMRT but binds ASC-2 indirectly via an adaptor.
- Histone deacetylase inhibitors do not block SMRT-mediated repression of Nur77.
- SMRT likely competes with an adaptor molecule for binding sites on Nur77.
Induction of cell cycle arrest and morphological differentiation by Nurr1 and retinoids in dopamine MN9D cells.
Castro DS, Hermanson E, Joseph B, Wallén A, Aarnisalo P, Heller A, Perlmann T
This study shows that Nurr1 and retinoids can force immature dopamine cells to stop dividing and mature in a laboratory dish. The findings describe basic cellular mechanisms of differentiation but do not involve human patients or animal models.
- Nurr1 induces cell cycle arrest and morphological differentiation in dopamine MN9D cells.
- Retinoids promote differentiation independently of Nurr1 in this cell line model.
- Related receptors NGFI-B and Nor1 also induce growth inhibition and differentiation.
- The mechanism relies on DNA binding without requiring RXR heterodimerization.
A clonal line of mesencephalic progenitor cells converted to dopamine neurons by hematopoietic cytokines: a source of cells for transplantation in Parkinson's disease.
Carvey PM, Ling ZD, Sortwell CE, Pitzer MR, McGuire SO, Storch A, Collier TJ
Clonally expanded rat mesencephalic progenitor cells differentiate into dopamine neurons when treated with specific cytokines and restore motor function in a Parkinson's disease rat model. This study demonstrates that hematopoietic cytokines can reliably convert these progenitors into functional dopamine neurons suitable for transplantation.
- Rat mesencephalic progenitor cells differentiate into dopamine neurons using interleukin-1, IL-11, LIF, and GDNF.
- A single clonal line achieved 98% conversion to tyrosine hydroxylase-positive neurons.
- Transplanted cells significantly reduced rotational asymmetry in dopamine-depleted rats.
- Differentiated cells maintained stability after cryopreservation and multiple culture passages.
In vitro regulated expression of tyrosine hydroxylase in ventral midbrain neurons from Nurr1-null mouse pups.
Eells JB, Rives JE, Yeung SK, Nikodem VM
This study shows that dopaminergic neuron precursors in mice lacking the Nurr1 gene remain undifferentiated and can be induced to produce tyrosine hydroxylase when treated with specific chemical agents in a lab dish. The research demonstrates that these cells retain some plasticity despite the genetic defect, suggesting potential pathways for cellular rescue. However, this is an in vitro mouse study with no direct clinical application or human data.
- Nurr1-null mouse neurons remain undifferentiated and can express tyrosine hydroxylase in culture.
- Forskolin treatment significantly increases the percentage of tyrosine hydroxylase-positive neurons.
- Combining forskolin, BDNF, and dopamine further enhances tyrosine hydroxylase expression.
- GDNF and BDNF alone do not induce tyrosine hydroxylase in these Nurr1-null cells.
- The study uses mouse pups and cell cultures, providing no human clinical evidence.
Physiological patterns of electrical stimulation can induce neuronal gene expression by activating N-type calcium channels.
Brosenitsch TA, Katz DM
Physiological electrical stimulation patterns activate N-type calcium channels to drive the expression of neuronal genes, including NR4A2 (Nurr1), through distinct signaling pathways than chronic depolarization. This mechanism links specific neural activity patterns directly to gene regulation via PKA and PKC kinases rather than the MAPK pathway.
- Patterned stimulation activates N-type calcium channels to induce NR4A2 expression.
- Chronic depolarization relies on L-type channels, a different mechanism entirely.
- NR4A2 induction by patterned activity requires PKA and PKC kinases.
- The MAPK pathway does not mediate this specific gene expression response.
Pitx3 activates mouse tyrosine hydroxylase promoter via a high-affinity binding site.
Lebel M, Gauthier Y, Moreau A, Drouin J
This study shows that the transcription factor Pitx3 directly activates the tyrosine hydroxylase gene in mouse neurons, while Nurr1 (NR4A2) has no effect on this specific promoter. The findings highlight distinct regulatory mechanisms for dopamine-related genes in midbrain development. This work does not provide new insights into NR4A2 function or potential treatments for NR4A2-related syndromes.
- Pitx3 activates the tyrosine hydroxylase promoter via a specific binding site in mice.
- Nurr1 (NR4A2) does not influence tyrosine hydroxylase promoter activity in this model.
- The study focuses on mouse neuronal development, not human genetics or therapy.
- Results suggest Pitx3 and Nurr1 regulate dopamine pathways through different mechanisms.
Involvement of the nuclear orphan receptor NURR1 in the regulation of corticotropin-releasing hormone expression and actions in human inflammatory arthritis.
Murphy EP, McEvoy A, Conneely OM, Bresnihan B, FitzGerald O
This study shows that the protein NURR1 helps drive inflammation in human joints affected by arthritis. It finds that inflammatory signals increase NURR1 levels, which then regulate other molecules involved in the immune response within the joint tissue.
- NURR1 is abundant in inflammatory cells within arthritic joints.
- Inflammatory cytokines increase NURR1 expression in synovial tissue.
- Glucocorticoids suppress the production of NURR1 mRNA.
- NURR1 mediates inflammatory responses in human arthritis models.
Distribution of the orphan nuclear receptor Nurr1 in medaka (Oryzias latipes): cues to the definition of homologous cell groups in the vertebrate brain.
Kapsimali M, Bourrat F, Vernier P
This study maps where the NR4A2 gene is active in fish brains to understand how brain structures evolved across vertebrates. It confirms that specific brain regions containing NR4A2 in fish correspond to similar regions in mammals, supporting the idea that these neural pathways are evolutionarily conserved. The research provides no direct information on human disease mechanisms or treatments for NR4A2-related syndromes.
- Researchers identified the NR4A2 gene equivalent in medaka fish and mapped its activity in their brains.
- NR4A2 appears in many brain areas, including those linked to nerve function and hormone regulation.
- The study compares fish and mammal brains to identify evolutionarily similar cell groups.
- Results suggest the role of NR4A2 in nervous system development is conserved across vertebrates.
- No human clinical data, patient outcomes, or therapeutic strategies are presented.
Nurr1 enhances transcription of the human dopamine transporter gene through a novel mechanism.
Sacchetti P, Mitchell TR, Granneman JG, Bannon MJ
This study identifies a new way the NR4A2 protein regulates dopamine transporter production in dopaminergic neurons. It shows that NR4A2 activates this gene through a mechanism that does not require its usual binding sites, suggesting complex control over dopamine signaling.
- NR4A2 increases transcription of the human dopamine transporter gene.
- This activation occurs independently of heterodimerization with RXR receptors.
- The mechanism bypasses standard NBRE-like binding sites on the DNA.
- Findings come from cell line experiments, not human or animal models.
Parathyroid hormone induces expression of the nuclear orphan receptor Nurr1 in bone cells.
Tetradis S, Bezouglaia O, Tsingotjidou A
Parathyroid hormone triggers the production of Nurr1 in mouse bone cells through a specific signaling pathway. This finding describes a molecular mechanism in osteoblasts and does not provide information about human neurodevelopment or clinical outcomes for NR4A2-related syndromes.
- The study uses primary mouse osteoblasts, not human neural tissue or patient samples.
- It investigates bone cell biology rather than dopaminergic neuron function or development.
- No clinical data, patient phenotypes, or treatment effects in humans are reported.
- Nurr1 induction occurs via the cAMP/PKA pathway in response to parathyroid hormone.
Expression of Nuclear Orphan Receptors Ngfi-B/Tr3, Nurr1 And Nor-1 after Global Brain Ischemia in Rat.
Schmidt-Kastner R, Zetterstr M R, Hakim AM
This study examines how three specific nuclear receptors, including Nurr1 (NR4A2), change their expression levels in rat brains following global ischemia. It provides no information on human NR4A2-related syndromes or potential treatments for affected children.
- The research focuses on rat models of brain ischemia, not human genetic conditions.
- It measures Nurr1 expression changes after oxygen deprivation in animal tissue.
- No clinical data, patient phenotypes, or therapeutic interventions are reported.
- The findings do not translate to current management of NR4A2-related syndromes.
Stress induces zinc finger immediate early genes in the rat adrenal gland.
Honkaniemi J, Zhang JS, Longo FM, Sharp FR
Stress rapidly activates the Nurr1 gene in rat adrenal glands alongside other immediate-early genes, suggesting it plays a role in hormone secretion during stress responses. This study provides no information on human NR4A2 variants, neurodevelopmental phenotypes, or potential treatments for children with NR4A2-related syndromes.
- Nurr1 activates quickly in rat adrenal glands after stress exposure.
- The study focuses on hormone secretion mechanisms in rats.
- No human data, clinical cohorts, or treatment implications are presented.
- Findings do not address NR4A2-related neurodevelopmental disorders.
Hippocampal expression of the orphan nuclear receptor gene hzf-3/nurr1 during spatial discrimination learning.
Peña de Ortiz S, Maldonado-Vlaar CS, Carrasquillo Y
This study shows that the NR4A2 gene becomes more active in the rat hippocampus when animals learn a spatial memory task. The findings link NR4A2 expression to long-term memory formation in rodents but do not address human disease mechanisms or treatment options.
- NR4A2 mRNA levels rise in rat hippocampus during spatial learning.
- Increased expression occurs specifically in CA1 and CA3 brain regions.
- The study uses a maze-based food search task in adult rats.
- No human data, clinical trials, or therapeutic implications are presented.
Identification of a potential nurr1 response element that activates the tyrosine hydroxylase gene promoter in cultured cells.
Iwawaki T, Kohno K, Kobayashi K
This study identifies a specific DNA sequence in the tyrosine hydroxylase gene that allows Nurr1 to activate dopamine production in cultured cells. It confirms the molecular mechanism by which NR4A2 regulates the enzyme necessary for dopamine synthesis. This work provides foundational biological context but offers no direct clinical guidance or treatment options for patients.
- Nurr1 directly activates the tyrosine hydroxylase gene promoter in cultured cells.
- Researchers identified a specific Nurr1 response element within the TH gene promoter.
- This mechanism explains how NR4A2 controls dopamine-producing neuron development.
- The study uses cell lines, not human patients or animal models.
- Findings describe basic molecular biology without clinical application.
The aging process: where are the drug opportunities?
Smith RG
This review identifies Nurr1 as a potential drug target for Parkinson's disease and highlights other emerging therapeutic avenues in aging research. It does not provide specific information, genetic insights, or treatment protocols relevant to NR4A2-related syndromes.
- Nurr1 is identified as a potential drug target for Parkinson's disease treatment.
- Growth hormone secretagogue receptor agonists show rejuvenating properties in aging research.
- The paper reviews general aging mechanisms without focusing on NR4A2 or related conditions.
- No human clinical data or specific guidance for NR4A2 families is included.
A response element for the homeodomain transcription factor Ptx3 in the tyrosine hydroxylase gene promoter.
Cazorla P, Smidt MP, O'Malley KL, Burbach JP
The transcription factor Ptx3 binds to the promoter of the tyrosine hydroxylase gene and enhances its activity in dopaminergic neurons, particularly when working together with Nurr1. This interaction suggests that Ptx3 helps regulate the production of dopamine-related enzymes in specific brain regions.
- Ptx3 binds to a specific site on the tyrosine hydroxylase gene promoter.
- Ptx3 enhances TH gene activity eight- to twelve-fold in neuroblastoma cells.
- Nurr1 significantly boosts the ability of Ptx3 to activate the TH promoter.
- Ptx3 represses TH activity in non-neuronal kidney cells, showing cell-type specificity.
Epigenetic cues in midbrain dopaminergic neuron development.
Perrone-Capano C, Da Pozzo P, di Porzio U
This review outlines the normal developmental steps required for midbrain dopaminergic neurons to form and function, highlighting the essential role of the transcription factor Nurr1 (NR4A2). It describes how external signals and target tissue interactions guide these neurons from initial commitment to mature neurotransmitter activity. The paper provides a baseline understanding of healthy neuron development rather than specific insights into NR4A2-related syndromes.
- Nurr1 is required for the final determination of midbrain dopaminergic neurons.
- Sonic Hedgehog and FGF8 act as initial extracellular inducers for these cells.
- Target tissue interaction modulates dopamine function in developing neurons.
- Dopamine synthesis occurs shortly after Nurr1 expression during development.
Genetic and epigenetic control of midbrain dopaminergic neuron development.
Perrone-Capano C, Di Porzio U
This review outlines the molecular steps required for midbrain dopaminergic neurons to develop and function, highlighting the essential roles of Nurr1 (NR4A2) and Ptx3 transcription factors. It describes how these genes interact with signaling molecules like Sonic hedgehog and FGF8 to specify neuron identity and coordinate synaptic connections.
- Nurr1 and Ptx3 are required for the final determination of dopaminergic neurons.
- Sonic hedgehog and FGF8 commit progenitor cells to become dopaminergic neurons.
- Target cell interactions modulate dopamine synthesis and uptake functions.
- Grafted neurons mature similarly to naturally developing fetal neurons.
The lack of Nurr1 does not effect cholecystokinin mRNA expression in the ventral midbrain in newborn mouse.
Baffi J, Witta J, Mezey E, Nikodem VM, Palkovits M
This study found that removing the Nurr1 gene in newborn mice does not change the levels of cholecystokinin mRNA in the ventral midbrain, suggesting that Nurr1 is not required for cholecystokinin expression in this brain region during early development.
- Nurr1 is not needed for cholecystokinin mRNA in newborn mouse midbrain
- No change in cholecystokinin levels when Nurr1 is absent
- Findings suggest Nurr1's role may be limited to other genes or brain areas
Activity of the Nurr1 carboxyl-terminal domain depends on cell type and integrity of the activation function 2.
Castro DS, Arvidsson M, Bondesson Bolin M, Perlmann T
This study shows that the Nurr1 protein can activate genes on its own without needing a known ligand, but this ability depends heavily on the specific cell type and other cellular factors. It identifies unique features of the AF2 region that drive this activity and notes that standard coactivators do not stimulate Nurr1 as they do other receptors. The findings suggest that an unknown ligand might eventually modulate Nurr1's function in the brain, but no direct treatment pathway is established.
- Nurr1 activates genes constitutively without a known ligand in certain cell types.
- The AF2 region drives this activation independently of external signals.
- Standard coactivators like SRC-1 do not stimulate Nurr1 activity.
- Cell type and DNA binding mode determine Nurr1's transcriptional capacity.
- Results hint at an unidentified ligand but offer no immediate clinical application.
A selective group of dopaminergic neurons express Nurr1 in the adult mouse brain.
Bäckman C, Perlmann T, Wallén A, Hoffer BJ, Morales M
This study maps where the Nurr1 protein is found in adult mouse brains, showing it is present in most midbrain and olfactory dopaminergic neurons but absent in others. It confirms that Nurr1 is not required for all dopamine-producing cells in the brain.
- Nurr1 is present in 91-96% of midbrain dopaminergic neurons in adult mice.
- Most olfactory bulb dopaminergic neurons also express Nurr1.
- Hypothalamic and arcuate nucleus dopamine neurons do not express Nurr1.
- Nurr1 is absent from brainstem noradrenergic neurons.
- The study uses mouse tissue, not human patients or clinical data.
4.5 kb of the rat tyrosine hydroxylase 5' flanking sequence directs tissue specific expression during development and contains consensus sites for multiple transcription factors.
Schimmel JJ, Crews L, Roffler-Tarlov S, Chikaraishi DM
This study identifies specific DNA sequences in the rat tyrosine hydroxylase gene that control its expression in dopamine-producing neurons and lists Nurr1 (NR4A2) as one of the transcription factors binding to these regions. It confirms that a 4.5 kb segment of this promoter is sufficient to drive correct developmental expression patterns in transgenic mice. The work provides foundational molecular data on how NR4A2 interacts with dopamine pathway genes but does not test treatments or analyze human patients.
- The 4.5 kb rat TH promoter drives specific expression in dopamine neurons during development.
- Nurr1 (NR4A2) binding sites are present within this regulatory DNA region.
- Transgenic mice show accurate tissue-specific expression patterns using this fragment.
- Peripheral nerve expression differs from central nervous system expression in adults.
- The study maps transcription factor interactions without testing clinical interventions.
Characterization of the 5'-flanking region of the human dopamine transporter gene.
Sacchetti P, Brownschidle LA, Granneman JG, Bannon MJ
This study maps the regulatory DNA region controlling the dopamine transporter gene and confirms that the protein Nurr1 (encoded by NR4A2) increases its activity in laboratory cell cultures. It provides mechanistic insight into how NR4A2 influences dopamine signaling but does not test treatments or analyze patient outcomes. The findings are basic molecular biology with no direct clinical application for your child at this time.
- Researchers mapped the DNA region controlling the human dopamine transporter gene.
- Nurr1 protein increases the activity of the dopamine transporter in cell studies.
- The study identifies specific DNA binding sites where Nurr1 acts on the gene.
- No animal models, patient data, or treatment trials are included in this work.
Heterodimerization between members of the Nur subfamily of orphan nuclear receptors as a novel mechanism for gene activation.
Maira M, Martens C, Philips A, Drouin J
This study demonstrates that Nurr1 (NR4A2) and related proteins form pairs to activate genes more effectively than when they act alone. It identifies specific DNA sequences that determine which gene combinations are activated by these protein pairs.
- Nurr1 and Nur77 form heterodimers that boost gene transcription synergistically.
- Protein pairing is essential for potent activation of target genes.
- Specific DNA sequences dictate which gene subsets respond to these dimers.
Reduced Nurr1 expression increases the vulnerability of mesencephalic dopamine neurons to MPTP-induced injury.
Le W, Conneely OM, He Y, Jankovic J, Appel SH
Reduced levels of the Nurr1 protein make dopamine neurons more sensitive to damage from toxins. This suggests that partial loss of NR4A2 function may lower the threshold for environmental or other stressors to harm these specific brain cells. The study does not provide direct evidence of clinical outcomes or treatments for humans.
- Heterozygous Nurr1 reduction does not cause neuron loss in healthy conditions.
- Reduced Nurr1 increases vulnerability to MPTP neurotoxin in mouse models.
- Nurr1 helps maintain mature dopamine neuron function under stress.
- Findings are preclinical and do not translate directly to human therapy.
Identification of nuclear orphan receptors as regulators of expression of a neurotransmitter receptor gene.
Chew LJ, Huang F, Boutin JM, Gallo V
This study identifies NURR1 (NR4A2) as a transcriptional repressor that binds to the GRIK5 gene, which encodes a specific glutamate receptor subunit. The research demonstrates that this interaction down-regulates the expression of the kainate-preferring glutamate receptor in neural tissue.
- NURR1 acts as a transcriptional repressor for the GRIK5 gene in rat brain tissue.
- The study uses rat brain extracts and cell lines to identify protein-DNA interactions.
- No human data, clinical outcomes, or therapeutic implications are presented.
- Findings focus on molecular mechanisms of gene regulation rather than disease treatment.