PRR7 is a novel NMDA-dependent inhibitor of c-Jun ubiquitination in neurons
Ontology highlight
ABSTRACT:
ORGANISM(S): Rattus norvegicus
PROVIDER: GSE62686 | GEO | 2014/10/25
SECONDARY ACCESSION(S): PRJNA264800
REPOSITORIES: GEO
Similar Datasets
Project description:Elevated c-Jun levels result in apoptosis and are evident in neurodegenerative disorders such as Alzheimer's disease and dementia and after global cerebral insults such as stroke and epilepsy. NMDA receptor (NMDAR) antagonists block c-Jun upregulation and prevent neuronal cell death following excitotoxic insults. However, little is known about the molecular mechanisms that regulate c-Jun abundance in neurons. Here we show that PRR7, a component of synaptic junctions, can upregulate c-Jun levels by inhibiting its ubiquitination in neurons. PRR7 interacts with the GLUN1 subunit of NMDARs and is upregulated in the nucleus following NMDAR activation. We show that PRR7 interacts with the E3 ligase SCFFBW7 (FBW7) and blocks the FBW7-mediated ubiquitination of c-Jun. PRR7 overexpression increases c-Jun-dependent transcriptional activity and promotes neuronal death. Microarray assays indicate that both Prr7 knockdown or overexpression alter the abundance of c-Jun-regulated transcripts associated with cellular viability as well as synaptic function. Moreover, Prr7 knockdown attenuates NMDA-mediated excitotoxicity in primary neuronal cultures. Our results show that PRR7 links NMDAR activity to c-Jun function and provide insight into the processes that underlie NMDA-dependent excitotoxicity. Four biological replicas of each of the four conditions: NO = not transduced with virus; NT = transduced with control lentiviruses containing a non-targeting shRNA sequence; KD = transduced with lentiviruses expressing PRR7-specific shRNAs; OE= transduced with lentiviruses to overexpress PRR7.
2014-10-25 | E-GEOD-62686 | biostudies-arrayexpress
Project description:PRR7 is a novel NMDA-dependent inhibitor of c-Jun ubiquitination in neurons
| PRJNA264800 | ENA
Project description:The cellular consequences of N-Methyl-D-Aspartate receptor (NMDAR) stimulation depend on the receptors’ subcellular localization. Synaptic NMDARs promote plasticity and survival whereas extrasynaptic NMDARs mediate excitotoxicity and contribute to cell death in neurodegenerative diseases. The mechanisms that couple activation of extrasynaptic NMDARs to cell death remain incompletely understood. We here show that activation of extrasynaptic NMDARs by bath application of NMDA or L-glutamate leads to the upregulation of a group of 19 microRNAs in cultured mouse hippocampal neurons. In contrast, none of these microRNAs is induced upon stimulation of synaptic activity. Increased microRNA expression depends on the pri-miRNA processing enzyme Drosha, but not on de novo gene transcription. These findings suggest that toxic NMDAR signaling involves changes in the expression levels of particular microRNAs.
2020-01-13 | GSE47601 | GEO
Project description:MK-801, a non-competitive NMDA receptor (NMDAR) antagonist, disturbs NMDAR function in rodents and induces psychological and behavioral changes similar to schizophrenia(SCZ). However, the effects of MK-801 treatment on gene expression in prefrontal cortex (PFC) are largely unknown. We have established MK-801 animal models to explore the etiology and pathophysiology of schizophrenia. Transcriptome analysis of the prefrontal cortex reveals that the differentially expressed genes mainly aggregate in chemical synaptic transmission and immune system process. Gene association patterns which are involved in synaptic vesicle cycle and mitochondrial electron transport chain have also been altered. Together, these observations underscore that dysfunction in glutamatergic synaptic vesicle cycle and mitochondrial electron transport chain has an impact on the pathogenesis of SCZ.
2019-03-12 | GSE111708 | GEO
Project description:Specific autoantibodies against the NMDA-receptor (NMDAR) GluN1 subunit cause severe and debilitating NMDAR-encephalitis. Autoantibodies induce prototypic disease symptoms resembling schizophrenia, including psychosis and cognitive dysfunction. Using a mouse passive transfer model applying human monoclonal anti-GluN1-autoantibodies, we observed CA1 pyramidal neuron hypoexcitability, reduced AMPA-receptor (AMPAR) signaling, and faster synaptic inhibition resulting in disrupted excitatory-inhibitory balance. Functional alterations were supported by widespread remodeling of the hippocampal proteome, including changes in glutamatergic and GABAergic neurotransmission. At the network level, anti-GluN1-autoantibodies amplified gamma oscillations and disrupted theta-gamma coupling. A data-informed network model revealed that lower AMPAR strength and faster GABAA-receptor current kinetics chiefly account for these abnormal oscillations. As predicted by our model and evidenced experimentally, positive allosteric modulation of AMPARs alleviated aberrant gamma activity and thus reinforced the causative effects of the excitatory-inhibitory imbalance. Collectively, NMDAR-hypofunction-induced aberrant synaptic, cellular, and network dynamics provide new mechanistic insights into disease symptoms in NMDAR-encephalitis and schizophrenia.
2023-09-24 | PXD032055 | Pride
Project description:Primary cortical neurons were isolated from E15 mice and after 5 days in vitro were untreated or treated for 24 h with mesenchymal stem cell conditioned medium and then untreated or treated for a further 24 h with NMDA. Neuron gene expression was profiled and compared between the four different conditions (neurons, neurons+MSC cm, neurons+NMDA, neurons+MSC cm+NMDA) to investigate the molecular mechanisms of MSC neuroprotection. Mesenchymal stem cells (MSC) promote functional recovery in experimental models of central nervous system (CNS) pathology and are currently being tested in clinical trials for stroke, multiple sclerosis and CNS injury. Their beneficial effects are attributed to activation of endogenous CNS repair processes and immune regulation but their mechanisms of action are poorly understood. Here we investigated the neuroprotective effects of MSC in simplified MSC-neuron co-culture systems and in mice using models of glutamate excitotoxicity. MSC protected primary cortical neurons against glutamate (NMDA) receptor-induced death and conditioned medium from MSC (MSC cm), but not control NIH3T3 cells, was sufficient for this effect. MSC cm neuroprotection in mouse cortical neurons was reduced by neutralizing antibodies to bFGF and associated with altered gene expression in neurons towards an immature phenotype as well as reduced neuronal Grin1, Grin2a and Grin2b mRNA levels in response to NMDA stimulation. Further, MSC cm neuroprotection in rat retinal ganglion cells was associated with absence of glutamate-induced calcium influx. Adoptive transfer of EGFP+MSC in a mouse kainic acid seizure model reduced CA3 neuron damage and hippocampal astrocytosis and resulted in the increased expression of neuronal genes that are upregulated by MSC cm, Bmi1, Ddx4, Ezh1, in the hippocampus. These results show that MSC mediate direct neuroprotection against glutamate excitotoxicity by secreting bFGF, reducing glutamate receptor expression and function and altering neuron gene expression towards an immature pattern, and provide evidence for a link between the therapeutic effects of MSC and the activation of endogenous repair processes following CNS injury. In vitro cultures primary cortical neurons from mice were protected from glutamate excitotoxicity when pre-treated with MSC cm. Global gene expression changes induced in neurons before and after treatment with MSC cm and/or NMDA were investigated using a cDNA spotted macroarray filter. Four samples were analysed in duplicate: neurons alone (untreated), neurons+MSC cm, neurons+NMDA, neurons+MSC cm+NMDA.
2011-05-01 | E-GEOD-26279 | biostudies-arrayexpress
Project description:Local cerebral hypoperfusion causes ischemic stroke while driving multiple cell-specific responses including inflammation, glutamate-NMDAR-mediated neurotoxicity, edema formation and angiogenesis. Despite the relevance of these pathophysiological mechanisms for disease progression and outcome, molecular determinants controlling the onset of these processes are only partially understood. In this context, our study intended to investigate the functional role of EphB2 – a receptor tyrosine kinase that is crucial for synapse function and binds to membrane-associated ephrin-B ligands. Cerebral ischemia was induced in EphB2-deficient mice by transient middle cerebral artery occlusion followed by different times (6, 12, 24 and 48 h) of reperfusion. Histological, neurofunctional and transcriptome analyses indicated an increase in EphB2 phosphorylation under these conditions and attenuated progression of stroke in EphB2-deficient mice. Moreover, while infiltration of microglia/macrophages and astrocytes into the peri-infarct region was not altered, expression of the pro-inflammatory mediators MCP-1 or IL-6 was decreased in these mice. In fact, in vitro analyses indicated that binding of EphB2 to astrocytic ephrin-B ligands stimulates NF-κB-mediated cytokine expression via the MAPK pathway. Further magnetic resonance imaging of the EphB2-deficient ischemic brain revealed a lower level of neuronal cytotoxic edema formation within 6 h upon onset of reperfusion. On the mechanistic level, absence of neuronal EphB2 decreased the mitochondrial Ca2+ load upon activation of NMDAR but not AMPAR. Moreover, activation of EphB2 by ephrin-B2 enhanced the NMDA-evoked excitotoxic neuronal cell death in vitro while neuron-specific loss of ephrin-B2 reduced the extent of cerebral tissue damage in the acute phase of ischemic stroke. Collectively, EphB2 may promote the immediate response to an ischemia-reperfusion event in the central nervous system by (i) pro-inflammatory activation of astrocytes via ephrin-B-dependent signalling and (ii) amplification of the NMDA-evoked neuronal excitotoxicity.
2019-02-13 | GSE120565 | GEO
Project description:Inhibition or genetic deletion of poly(ADP-ribose) polymerase-1 (PARP-1) is profoundly protective against a number of toxic insults in many organ systems1,2. In the brain the molecular mechanisms underlying PARP-1-dependent cell death (parthanatos) involves mitochondrial apoptosis-inducing factor (AIF) release and translocation to the nucleus resulting in chromatinolysis3-5. However, it is not known how AIF induces chromatinolysis and neuronal death in parthanatos3. Here we show through an unbiased screen of a ~16K human protein microarray followed by a second siRNA-based screen for protection against PARP-1- dependent cell death, that macrophage migration inhibitory factor (MIF)6 is an AIF associated nuclease that is required for cell death following N-methyl-D-aspartate (NMDA) glutamate receptor excitotoxicity and N-methyl-N-nitroso-N- nitroguanidine (MNNG) toxicity in primary neuronal cultures and focal stroke in mice. MIF contains a central four stranded mixed β-sheet flanked by two α- helices on both sides with an αβββαβ topology which is the structural core of many proteins belonging to the PD-D/E(X)K nuclease-like superfamily. MIF possesses previously unknown Mg2+/Ca2+-dependent nuclease activity, cleaving genomic DNA into large 20-50 kb fragments. AIF recruits MIF to the nucleus after NMDA treatment to induce DNA damage and cell death. Disruption of the AIF-MIF interaction prevents MIF recruitment to the nucleus and protects neurons from NMDA excitotoxicity and ischemic injury. Mutation of Glu22 to Gln in the catalytic nuclease domain completely blocks MIF’s nuclease activity, which almost completely inhibits DNA damage and cell death in vitro and in vivo. These findings reveal that MIF is recruited by AIF to the nucleus where it functions as a parthanatos dependent AIF associated nuclease that induces chromatinolysis and neuronal death, providing a new therapeutic target for stroke and other disorders involving parthanatos.
2016-12-19 | GSE65110 | GEO
Project description:Deciphering the molecular pathways associated with N-methyl-D-aspartate receptor (NMDAr) hypofunction and its interaction with antipsychotics is necessary to advance our understanding of the basis of schizophrenia, as well as our capacity to treat this disease. In this regard, the development of human brain-derived models amenable for studying the neurobiology of schizophrenia may contribute to fill the gaps led by the widely employed animal models. Here we assessed the proteomic changes induced by the NMDA glutamate receptor antagonist MK-801 on human brain slice cultures obtained from adult donors submitted to resective neurosurgery. Initially, we demonstrated that MK-801 diminishes NMDA glutamate receptor signaling in human brain slices in culture. Next, using mass- spectrometry-based proteomics and systems biology in silico analyses, we found that MK-801 led to alterations in proteins related to several pathways previously associated with schizophrenia pathophysiology including ephrin, opioid, melatonin, sirtuin signaling, interleukin 8, endocannabinoid and synaptic vesicle cycle. We also evaluated the impact of both typical and atypical antipsychotics on MK-801-induced proteome changes. Interestingly, the atypical antipsychotic clozapine showed a more significant capacity to counteract the protein alterations induced by NMDAr hypofunction than haloperidol. Finally, using our dataset we identified potential modulators of the MK-801-induced proteome changes, which may be considered promising targets to treat NMDAr hypofunction in schizophrenia.
2024-02-06 | PXD046944 | Pride
Project description:The central nervous system encounters a number of challenges following HIV infection, leading to increased risk for a collection of neurocognitive symptoms clinically classified as HIV-associated neurocognitive disorders (HAND). Studies attempting to identify causal mechanisms and potential therapeutic interventions have historically relied on primary rodent neurons, but a number of recent reports take advantage of iPSC-derived neurons in order to study these mechanisms in a readily-reproducible, human model. We found that iPSC-derived neurons differentiated via an inducible neurogenin-2 transcription factor were resistant to gross toxicity from a number of HIV-associated insults previously reported to be toxic in rodent models, including HIV-infected myeloid cell supernatants and the integrase inhibitor antiretroviral drug, elvitegravir. Further examination of these cultures revealed robust resistance to NMDA receptor-mediated toxicity. We then performed a comparative analysis of iPSC neurons exposed to integrase inhibitors and activated microglial supernatants to study sub-cytotoxic alterations in micro electrode array (MEA)-measured neuronal activity and gene expression, identifying extracellular matrix interaction/morphogenesis as the most consistently altered pathways across HIV-associated insults. These findings illustrate that HIV-associated insults dysregulate human neuronal activity and organization even in the absence of gross NMDA-mediated neurotoxicity, which has important implications on the effects of these insults in neurodevelopment and on the interpretation of primary vs. iPSC in vitro neuronal studies.
2024-01-20 | GSE250609 | GEO