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1.
PLoS Genet ; 16(2): e1008626, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32059017

RESUMO

Neuronal pruning is a commonly observed phenomenon for the developing nervous systems to ensure precise wiring of neural circuits. The function of Ik2 kinase and its downstream mediator, Spindle-F (Spn-F), are essential for dendrite pruning of Drosophila sensory neurons during development. However, little is known about how Ik2/Spn-F signaling is transduced in neurons and ultimately results in dendrite pruning. Our genetic analyses and rescue experiments demonstrated that the small GTPase Rab11, especially the active GTP-bound form, is required for dendrite pruning. We also found that Rab11 shows genetic interactions with spn-F and ik2 on pruning. Live imaging of single neurons and antibody staining reveal normal Ik2 kinase activation in Rab11 mutant neurons, suggesting that Rab11 could have a functional connection downstream of and/or parallel to the Ik2 kinase signaling. Moreover, we provide biochemical evidence that both the Ik2 kinase activity and the formation of Ik2/Spn-F/Rab11 complexes are central to promote Rab11 activation in cells. Together, our studies reveal that a critical role of Ik2/Spn-F signaling in neuronal pruning is to promote Rab11 activation, which is crucial for dendrite pruning in neurons.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Quinase I-kappa B/metabolismo , Plasticidade Neuronal/genética , Células Receptoras Sensoriais/fisiologia , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Animais Geneticamente Modificados , Linhagem Celular , Dendritos/fisiologia , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Embrião não Mamífero , Técnicas de Silenciamento de Genes , Microscopia Intravital , Proteínas Associadas aos Microtúbulos/metabolismo , Células Receptoras Sensoriais/citologia , Transdução de Sinais/fisiologia , Imagem com Lapso de Tempo , Proteínas rab de Ligação ao GTP/genética
2.
PLoS One ; 15(1): e0227917, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978183

RESUMO

Experimental studies highlight the important role of the extracellular matrix (ECM) in the regulation of neuronal excitability and synaptic connectivity in the nervous system. In its turn, the neural ECM is formed in an activity-dependent manner. Its maturation closes the so-called critical period of neural development, stabilizing the efficient configurations of neural networks in the brain. ECM is locally remodeled by proteases secreted and activated in an activity-dependent manner into the extracellular space and this process is important for physiological synaptic plasticity. We ask if ECM remodeling may be exaggerated under pathological conditions and enable activity-dependent switches between different regimes of ECM expression. We consider an analytical model based on known mechanisms of interaction between neuronal activity and expression of ECM, ECM receptors and ECM degrading proteases. We demonstrate that either inhibitory or excitatory influence of ECM on neuronal activity may lead to the bistability of ECM expression, so two stable stationary states are observed. Noteworthy, only in the case when ECM has predominant inhibitory influence on neurons, the bistability is dependent on the activity of proteases. Excitatory ECM-neuron feedback influences may also result in spontaneous oscillations of ECM expression, which may coexist with a stable stationary state. Thus, ECM-neuronal interactions support switches between distinct dynamic regimes of ECM expression, possibly representing transitions into disease states associated with remodeling of brain ECM.


Assuntos
Matriz Extracelular/genética , Neurogênese/genética , Peptídeo Hidrolases/genética , Receptores de Superfície Celular/genética , Potenciais de Ação/genética , Animais , Encéfalo/metabolismo , Regulação da Expressão Gênica/genética , Humanos , Modelos Teóricos , Rede Nervosa/metabolismo , Plasticidade Neuronal/genética , Neurônios/metabolismo , Sinapses/genética
3.
J Surg Res ; 246: 113-122, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31563831

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is an under-recognized public health threat. Even mild brain injuries can lead to long-term neurologic impairment. Microglia play a fundamental role in the development and progression of this ensuing neurologic impairment. Despite this, a microglia-specific injury signature has yet to be identified. We hypothesized that TBI would lead to long-term changes in the transcriptional profile of microglial pathways associated with the development of subsequent neurologic impairment. MATERIALS AND METHODS: Male C57BL/6 mice underwent TBI via a controlled cortical impact and were followed longitudinally. FACSorted microglia from TBI mice were subjected to Quantiseq 3'-biased RNA sequencing at 7, 30, and 90 d after TBI. K-means clustering on 396 differentially expressed genes was performed, and gene ontology enrichment analysis was used to determine corresponding enriched processes. RESULTS: Differentially expressed genes in microglia exhibited four main patterns of expression over the course of TBI. In particular, we identified four gene clusters which corresponded to the host defense response, synaptic plasticity, lipid remodeling, and membrane polarization. CONCLUSIONS: Transcriptional profiling within individual populations of microglia after TBI remains a critical unmet research need within the field of TBI. This focused study identified several physiologic processes within microglia that may be associated with development of long-term neurologic impairment after TBI. These data demonstrate the capability of longitudinal transcriptional profiling to uncover potential cell-specific targets for the treatment of TBI.


Assuntos
Lesões Encefálicas Traumáticas/patologia , Microglia/patologia , Doenças do Sistema Nervoso/patologia , Transdução de Sinais/genética , Animais , Lesões Encefálicas Traumáticas/complicações , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Modelos Animais de Doenças , Progressão da Doença , Perfilação da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Família Multigênica/genética , Doenças do Sistema Nervoso/etiologia , Plasticidade Neuronal/genética , Fatores de Tempo , Regulação para Cima
4.
Int J Mol Sci ; 21(1)2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31878257

RESUMO

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by demyelinating white matter lesions and neurodegeneration, with a variable clinical course. Brain network architecture provides efficient information processing and resilience to damage. The peculiar organization characterized by a low number of highly connected nodes (hubs) confers high resistance to random damage. Anti-homeostatic synaptic plasticity, in particular long-term potentiation (LTP), represents one of the main physiological mechanisms underlying clinical recovery after brain damage. Different types of synaptic plasticity, including both anti-homeostatic and homeostatic mechanisms (synaptic scaling), contribute to shape brain networks. In MS, altered synaptic functioning induced by inflammatory mediators may represent a further cause of brain network collapse in addition to demyelination and grey matter atrophy. We propose that impaired LTP expression and pathologically enhanced upscaling may contribute to disrupting brain network topology in MS, weakening resilience to damage and negatively influencing the disease course.


Assuntos
Esclerose Múltipla/metabolismo , Animais , Encéfalo/metabolismo , Humanos , Inflamação/metabolismo , Potenciação de Longa Duração/genética , Potenciação de Longa Duração/fisiologia , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia
5.
Int J Mol Sci ; 20(19)2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31581735

RESUMO

Epilepsy represents one of the most common neurological disorders characterized by abnormal electrical activity in the central nervous system (CNS). Recurrent seizures are the cardinal clinical manifestation. Although it has been reported that the underlying pathological processes include inflammation, changes in synaptic strength, apoptosis, and ion channels dysfunction, currently the pathogenesis of epilepsy is not yet completely understood. Long non-coding RNAs (lncRNAs), a class of long transcripts without protein-coding capacity, have emerged as regulatory molecules that are involved in a wide variety of biological processes. A growing number of studies reported that lncRNAs participate in the regulation of pathological processes of epilepsy and they are dysregulated during epileptogenesis. Moreover, an aberrant expression of lncRNAs linked to epilepsy has been observed both in patients and in animal models. In this review, we summarize latest advances concerning the mechanisms of action and the involvement of the most dysregulated lncRNAs in epilepsy. However, the functional roles of lncRNAs in the disease pathogenesis are still to be explored and we are only at the beginning. Additional studies are needed for the complete understanding of the underlying mechanisms and they would result in the use of lncRNAs as diagnostic biomarkers and novel therapeutic targets.


Assuntos
Epilepsia/etiologia , Epilepsia/metabolismo , Regulação da Expressão Gênica , RNA Longo não Codificante/genética , Transdução de Sinais , Animais , Apoptose/genética , Biomarcadores , Diferenciação Celular/genética , Epigênese Genética , Perfilação da Expressão Gênica , Humanos , Plasticidade Neuronal/genética , Neurônios/citologia , Neurônios/metabolismo , Interferência de RNA
6.
Int J Mol Sci ; 20(17)2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31484392

RESUMO

Brain-derived neurotrophic factor (BDNF) has previously been shown to play an important role in glutamatergic synaptic plasticity in the amygdala, correlating with cued fear learning. While glutamatergic neurotransmission is facilitated by BDNF signaling in the amygdala, its mechanism of action at inhibitory synapses in this nucleus is far less understood. We therefore analyzed the impact of chronic BDNF depletion on GABAA-mediated synaptic transmission in BDNF heterozygous knockout mice (BDNF+/-). Analysis of miniature and evoked inhibitory postsynaptic currents (IPSCs) in the lateral amygdala (LA) revealed neither pre- nor postsynaptic differences in BDNF+/- mice compared to wild-type littermates. In addition, long-term potentiation (LTP) of IPSCs was similar in both genotypes. In contrast, facilitation of spontaneous IPSCs (sIPSCs) by norepinephrine (NE) was significantly reduced in BDNF+/- mice. These results argue against a generally impaired efficacy and plasticity at GABAergic synapses due to a chronic BDNF deficit. Importantly, the increase in GABAergic tone mediated by NE is reduced in BDNF+/- mice. As release of NE is elevated during aversive behavioral states in the amygdala, effects of a chronic BDNF deficit on GABAergic inhibition may become evident in response to states of high arousal, leading to amygdala hyper-excitability and impaired amygdala function.


Assuntos
Tonsila do Cerebelo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Potenciação de Longa Duração/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Feminino , Potenciação de Longa Duração/genética , Camundongos , Camundongos Knockout , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia , Técnicas de Patch-Clamp , Transmissão Sináptica/genética , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/metabolismo
7.
Nat Neurosci ; 22(10): 1718-1730, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31501571

RESUMO

Activity-driven transcription plays an important role in many brain processes, including those underlying memory and epilepsy. Here we combine genetic tagging of nuclei and ribosomes with RNA sequencing, chromatin immunoprecipitation with sequencing, assay for transposase-accessible chromatin using sequencing and Hi-C to investigate transcriptional and chromatin changes occurring in mouse hippocampal excitatory neurons at different time points after synchronous activation during seizure and sparse activation by novel context exploration. The transcriptional burst is associated with an increase in chromatin accessibility of activity-regulated genes and enhancers, de novo binding of activity-regulated transcription factors, augmented promoter-enhancer interactions and the formation of gene loops that bring together the transcription start site and transcription termination site of induced genes and may sustain the fast reloading of RNA polymerase complexes. Some chromatin occupancy changes and interactions, particularly those driven by AP1, remain long after neuronal activation and could underlie the changes in neuronal responsiveness and circuit connectivity observed in these neuroplasticity paradigms, perhaps thereby contributing to metaplasticity in the adult brain.


Assuntos
Epigenômica , Hipocampo/fisiologia , Neurônios/fisiologia , Animais , Cromatina/genética , Elementos Facilitadores Genéticos/genética , Genes Precoces/genética , Hipocampo/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia , Regiões Promotoras Genéticas/genética , Convulsões/genética , Convulsões/fisiopatologia , Estado Epiléptico/genética , Estado Epiléptico/fisiopatologia , Fator de Transcrição AP-1/genética , Transcrição Genética/genética , Transcrição Genética/fisiologia
8.
PLoS Genet ; 15(8): e1008352, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31449520

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopamine (DA) neurons in the substantia nigra pars compacta (SNc). Rare genetic mutations in genes such as Parkin, Pink1, DJ-1, α-synuclein, LRRK2 and GBA are found to be responsible for the disease in about 15% of the cases. A key unanswered question in PD pathophysiology is why would these mutations, impacting basic cellular processes such as mitochondrial function and neurotransmission, lead to selective degeneration of SNc DA neurons? We previously showed in vitro that SNc DA neurons have an extremely high rate of mitochondrial oxidative phosphorylation and ATP production, characteristics that appear to be the result of their highly complex axonal arborization. To test the hypothesis in vivo that axon arborization size is a key determinant of vulnerability, we selectively labeled SNc or VTA DA neurons using floxed YFP viral injections in DAT-cre mice and showed that SNc DA neurons have a much more arborized axon than those of the VTA. To further enhance this difference, which may represent a limiting factor in the basal vulnerability of these neurons, we selectively deleted in mice the DA D2 receptor (D2-cKO), a key negative regulator of the axonal arbour of DA neurons. In these mice, SNc DA neurons have a 2-fold larger axonal arborization, release less DA and are more vulnerable to a 6-OHDA lesion, but not to α-synuclein overexpression when compared to control SNc DA neurons. This work adds to the accumulating evidence that the axonal arborization size of SNc DA neurons plays a key role in their vulnerability in the context of PD.


Assuntos
Neurônios Dopaminérgicos/patologia , Plasticidade Neuronal/genética , Doença de Parkinson/patologia , Parte Compacta da Substância Negra/patologia , Receptores de Dopamina D2/genética , Animais , Axônios/patologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/patologia , Fosforilação Oxidativa , Doença de Parkinson/genética , Parte Compacta da Substância Negra/citologia , Receptores de Dopamina D2/metabolismo
9.
Int J Mol Sci ; 20(15)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344805

RESUMO

Autism Spectrum Disorder (ASD) is a developmental condition characterized by impaired communication and obsessive behavior that affects 1 in 59 children. ASD is expected to affect 1 in about 40 children by 2020, but there is still no distinct pathogenesis or effective treatments. Prenatal stress has been associated with higher risk of developing ASD in the offspring. Moreover, children with ASD cannot handle anxiety and respond disproportionately even to otherwise benign triggers. Stress and environmental stimuli trigger the unique immune cells, mast cells, which could then trigger microglia leading to abnormal synaptic pruning and dysfunctional neuronal connectivity. This process could alter the "fear threshold" in the amygdala and lead to an exaggerated "fight-or-flight" reaction. The combination of corticotropin-releasing hormone (CRH), secreted under stress, together with environmental stimuli could be major contributors to the pathogenesis of ASD. Recognizing these associations and preventing stimulation of mast cells and/or microglia could greatly benefit ASD patients.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Encéfalo/fisiopatologia , Mastócitos/metabolismo , Neurônios/metabolismo , Ansiedade/fisiopatologia , Ansiedade/psicologia , Transtorno do Espectro Autista/etiologia , Transtorno do Espectro Autista/psicologia , Medo/psicologia , Feminino , Humanos , Mastócitos/patologia , Microglia/patologia , Plasticidade Neuronal/genética , Neurônios/patologia , Gravidez
10.
PLoS Genet ; 15(6): e1008164, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31194737

RESUMO

Chronic pain is highly prevalent worldwide and represents a significant socioeconomic and public health burden. Several aspects of chronic pain, for example back pain and a severity-related phenotype 'chronic pain grade', have been shown previously to be complex heritable traits with a polygenic component. Additional pain-related phenotypes capturing aspects of an individual's overall sensitivity to experiencing and reporting chronic pain have also been suggested as a focus for investigation. We made use of a measure of the number of sites of chronic pain in individuals within the UK general population. This measure, termed Multisite Chronic Pain (MCP), is a complex trait and its genetic architecture has not previously been investigated. To address this, we carried out a large-scale genome-wide association study (GWAS) of MCP in ~380,000 UK Biobank participants. Our findings were consistent with MCP having a significant polygenic component, with a Single Nucleotide Polymorphism (SNP) heritability of 10.2%. In total 76 independent lead SNPs at 39 risk loci were associated with MCP. Additional gene-level association analyses identified neurogenesis, synaptic plasticity, nervous system development, cell-cycle progression and apoptosis genes as enriched for genetic association with MCP. Genetic correlations were observed between MCP and a range of psychiatric, autoimmune and anthropometric traits, including major depressive disorder (MDD), asthma and Body Mass Index (BMI). Furthermore, in Mendelian randomisation (MR) analyses a causal effect of MCP on MDD was observed. Additionally, a polygenic risk score (PRS) for MCP was found to significantly predict chronic widespread pain (pain all over the body), indicating the existence of genetic variants contributing to both of these pain phenotypes. Overall, our findings support the proposition that chronic pain involves a strong nervous system component with implications for our understanding of the physiology of chronic pain. These discoveries may also inform the future development of novel treatment approaches.


Assuntos
Dor Crônica/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Herança Multifatorial/genética , Adulto , Idoso , Asma/genética , Asma/fisiopatologia , Bancos de Espécimes Biológicos , Índice de Massa Corporal , Dor Crônica/fisiopatologia , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurogênese/genética , Plasticidade Neuronal/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Reino Unido
11.
Brain Struct Funct ; 224(6): 2213-2230, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31183559

RESUMO

The palmitoyl acyltransferase ZDHHC7 belongs to the DHHC family responsible for the covalent attachment of palmitic acid (palmitoylation) to target proteins. Among synaptic proteins, its main targets are sex steroid receptors such as the estrogen receptors. When palmitoylated, these couple to membrane microdomains and elicit non-genomic rapid responses. Such coupling is found particularly in cortico-limbic brain areas which impact structure, function, and behavioral outcomes. Thus far, the functional role of ZDHHC7 has not been investigated in this context. To directly analyze an impact of ZDHHC7 on brain anatomy, microstructure, connectivity, function, and behavior, we generated a mutant mouse in which the Zdhhc7 gene is constitutively inactivated. Male and female Zdhhc7-/- mice were phenotypically compared with wild-type mice using behavioral tests, electrophysiology, protein analyses, and neuroimaging with diffusion tensor-based fiber tractography. Zdhhc7-deficiency impaired excitatory transmission, synaptic plasticity at hippocampal Schaffer collateral CA1 synapses, and hippocampal structural connectivity in both sexes in similar manners. Effects on both sexes but in different manners appeared in medial prefrontal cortical synaptic transmission and in hippocampal microstructures. Finally, Zdhhc7-deficiency affected anxiety-related behaviors exclusively in females. Our data demonstrated the importance of Zdhhc7 for assembling proper brain structure, function, and behavior on a system level in mice in a sex-related manner. Given the prominent role of sex-specificity also in humans and associated mental disorders, Zdhhc7-/- mice might provide a promising model for in-depth investigation of potentially underlying sex-specifically altered mechanisms.


Assuntos
Aciltransferases/deficiência , Comportamento Animal/fisiologia , Plasticidade Neuronal/genética , Fatores Sexuais , Transmissão Sináptica/genética , Animais , Ansiedade/genética , Potenciais Pós-Sinápticos Excitadores/genética , Hipocampo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos Knockout , Plasticidade Neuronal/fisiologia , Córtex Pré-Frontal/metabolismo , Sinapses/genética , Sinapses/metabolismo , Transmissão Sináptica/fisiologia
12.
PLoS Genet ; 15(5): e1008176, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31150381

RESUMO

Gene expression changes in neural systems are essential for environment-induced behavioral plasticity in animals; however, neuronal signaling pathways mediating the effect of external stimuli on transcriptional changes are largely unknown. Recently, we have demonstrated that the neuropeptide F (NPF)/nitric oxide (NO) signaling pathway plays a regulatory role in phase-related locomotor plasticity in the migratory locust, Locusta migratoria. Here, we report that a conserved transcription factor, cAMP response element-binding protein B (CREB-B), is a key mediator involved in the signaling pathway from NPF2 to NOS in the migratory locust, triggering locomotor activity shift between solitarious and gregarious phases. We find that CREB-B directly activates brain NOS expression by interacting with NOS promoter region. The phosphorylation at serine 110 site of CREB-B dynamically changes in response to population density variation and is negatively controlled by NPF2. The involvement of CREB-B in NPF2-regulated locomotor plasticity is further validated by RNAi experiment and behavioral assay. Furthermore, we reveal that protein kinase A mediates the regulatory effects of NPF2 on CREB-B phosphorylation and NOS transcription. These findings highlight a precise signal cascade underlying environment-induced behavioral plasticity.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Locomoção/genética , Locusta migratoria/genética , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulação da Expressão Gênica/genética , Gafanhotos/genética , Gafanhotos/metabolismo , Locusta migratoria/metabolismo , Plasticidade Neuronal/genética , Neuropeptídeos/metabolismo , Neuropeptídeos/fisiologia , Óxido Nítrico/metabolismo , Óxido Nítrico/fisiologia , Fosforilação , Regiões Promotoras Genéticas/genética , Interferência de RNA , Serina/metabolismo , Transdução de Sinais
13.
Neuron ; 103(1): 66-79.e12, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31104951

RESUMO

The precision and reliability of synaptic information transfer depend on the molecular organization of voltage-gated calcium channels (VGCCs) within the presynaptic membrane. Alternative splicing of exon 47 affects the C-terminal structure of VGCCs and their affinity to intracellular partners and synaptic vesicles (SVs). We show that hippocampal synapses expressing VGCCs either with exon 47 (CaV2.1+47) or without (CaV2.1Δ47) differ in release probability and short-term plasticity. Tracking single channels revealed transient visits (∼100 ms) of presynaptic VGCCs in nanodomains (∼80 nm) that were controlled by neuronal network activity. Surprisingly, despite harboring prominent binding sites to scaffold proteins, CaV2.1+47 persistently displayed higher mobility within nanodomains. Synaptic accumulation of CaV2.1 was accomplished by optogenetic clustering, but only CaV2.1+47 increased transmitter release and enhanced synaptic short-term depression. We propose that exon 47-related alternative splicing of CaV2.1 channels controls synapse-specific release properties at the level of channel mobility-dependent coupling between VGCCs and SVs.


Assuntos
Canais de Cálcio/genética , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia , Sinapses/fisiologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , Canais de Cálcio/efeitos da radiação , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Células HEK293 , Humanos , Luz , Neurotransmissores/metabolismo , Optogenética , Gravidez , Isoformas de Proteínas/genética , Ratos , Vesículas Sinápticas/fisiologia
14.
Nat Commun ; 10(1): 2113, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-31068592

RESUMO

Gene editing by CRISPR/Cas9 is commonly used to generate germline mutations or perform in vitro screens, but applicability for in vivo screening has so far been limited. Recently, it was shown that in Drosophila, Cas9 expression could be limited to a desired group of cells, allowing tissue-specific mutagenesis. Here, we thoroughly characterize tissue-specific (ts)CRISPR within the complex neuronal system of the Drosophila mushroom body. We report the generation of a library of gRNA-expressing plasmids and fly lines using optimized tools, which provides a valuable resource to the fly community. We demonstrate the application of our library in a large-scale in vivo screen, which reveals insights into developmental neuronal remodeling.


Assuntos
Animais Geneticamente Modificados/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Drosophila/genética , Edição de Genes/métodos , Animais , Sistemas CRISPR-Cas/genética , Feminino , Masculino , Corpos Pedunculados/metabolismo , Mutagênese , Sistema Nervoso/crescimento & desenvolvimento , Plasticidade Neuronal/genética , Neurônios/fisiologia , Plasmídeos/genética , RNA Guia/genética
15.
Nature ; 569(7758): 708-713, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31068695

RESUMO

Neuronal-activity-dependent transcription couples sensory experience to adaptive responses of the brain including learning and memory. Mechanisms of activity-dependent gene expression including alterations of the epigenome have been characterized1-8. However, the fundamental question of whether sensory experience remodels chromatin architecture in the adult brain in vivo to induce neural code transformations and learning and memory remains to be addressed. Here we use in vivo calcium imaging, optogenetics and pharmacological approaches to show that granule neuron activation in the anterior dorsal cerebellar vermis has a crucial role in a delay tactile startle learning paradigm in mice. Of note, using large-scale transcriptome and chromatin profiling, we show that activation of the motor-learning-linked granule neuron circuit reorganizes neuronal chromatin including through long-distance enhancer-promoter and transcriptionally active compartment interactions to orchestrate distinct granule neuron gene expression modules. Conditional CRISPR knockout of the chromatin architecture regulator cohesin in anterior dorsal cerebellar vermis granule neurons in adult mice disrupts enhancer-promoter interactions, activity-dependent transcription and motor learning. These findings define how sensory experience patterns chromatin architecture and neural circuit coding in the brain to drive motor learning.


Assuntos
Retroalimentação Sensorial , Genoma , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Vias Neurais , Plasticidade Neuronal/genética , Animais , Proteínas de Ciclo Celular/metabolismo , Vermis Cerebelar/citologia , Vermis Cerebelar/metabolismo , Montagem e Desmontagem da Cromatina , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos/genética , Epigênese Genética , Feminino , Masculino , Camundongos , Fibras Musgosas Hipocampais , Regiões Promotoras Genéticas/genética , Células de Purkinje , Reflexo de Sobressalto
16.
Front Biosci (Landmark Ed) ; 24: 1203-1240, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31136976

RESUMO

Recent evidence demonstrates that long non-coding RNAs (lncRNAs) regulate the expression of multiple genes in an epigenetic, transcriptional, or post-transcriptional manner. They are involved in various cellular phenomena, such as the recruitment of transcription factors, epigenetic chaperoning, control of alternative splicing, mRNA stability and translational activity, as well as acting as decoys against microRNAs. In this review, we summarize the pivotal roles of lncRNAs in regulation of the gene expression involved in neural cell differentiation, synaptogenesis and synaptic plasticity in the central nervous system (CNS). We also describe the aberrant expression of multiple lncRNAs involved in the pathogenesis of neurological diseases. The abnormal expression of lncRNAs leads to altered expression levels of target genes, which contributes to neurodegenerative diseases, such as in Alzheimer's disease and Parkinson's disease, and to the formation of tumors, such as glioma. Accordingly, we discuss recent findings for the modes of action of lncRNAs in normal CNS development and for aberrant lncRNA actions in the pathogenesis of neuronal diseases.


Assuntos
Diferenciação Celular/genética , Sistema Nervoso Central/metabolismo , Regulação da Expressão Gênica , Doenças Neurodegenerativas/genética , Neurônios/metabolismo , RNA Longo não Codificante/genética , Doença de Alzheimer/genética , Sistema Nervoso Central/crescimento & desenvolvimento , Humanos , Plasticidade Neuronal/genética , Neurônios/citologia , Doença de Parkinson/genética
17.
ACS Appl Mater Interfaces ; 11(18): 16749-16757, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31025562

RESUMO

Nonvolatile, flexible artificial synapses that can be used for brain-inspired computing are highly desirable for emerging applications such as human-machine interfaces, soft robotics, medical implants, and biological studies. Printed devices based on organic materials are very promising for these applications due to their sensitivity to ion injection, intrinsic printability, biocompatibility, and great potential for flexible/stretchable electronics. Herein, we report the experimental realization of a nonvolatile artificial synapse using organic polymers in a scalable fabrication process. The three-terminal electrochemical neuromorphic device successfully emulates the key features of biological synapses: long-term potentiation/depression, spike timing-dependent plasticity learning rule, paired-pulse facilitation, and ultralow energy consumption. The artificial synapse network exhibits an excellent endurance against bending tests and enables a direct emulation of logic gates, which shows the feasibility of using them in futuristic hierarchical neural networks. Based on our demonstration of 100 distinct, nonvolatile conductance states, we achieved a high accuracy in pattern recognition and face classification neural network simulations.


Assuntos
Interfaces Cérebro-Computador , Plasticidade Neuronal/genética , Polímeros/química , Sinapses/química , Encéfalo/fisiologia , Eletrônica , Humanos , Plasticidade Neuronal/efeitos dos fármacos , Oxigênio/química , Gases em Plasma/química , Impressão Tridimensional , Robótica
18.
Genome Res ; 29(5): 857-869, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30936163

RESUMO

Here we present a comprehensive map of the accessible chromatin landscape of the mouse hippocampus at single-cell resolution. Substantial advances of this work include the optimization of a single-cell combinatorial indexing assay for transposase accessible chromatin (sci-ATAC-seq); a software suite, scitools, for the rapid processing and visualization of single-cell combinatorial indexing data sets; and a valuable resource of hippocampal regulatory networks at single-cell resolution. We used sci-ATAC-seq to produce 2346 high-quality single-cell chromatin accessibility maps with a mean unique read count per cell of 29,201 from both fresh and frozen hippocampi, observing little difference in accessibility patterns between the preparations. By using this data set, we identified eight distinct major clusters of cells representing both neuronal and nonneuronal cell types and characterized the driving regulatory factors and differentially accessible loci that define each cluster. Within pyramidal neurons, we identified four major clusters, including CA1 and CA3 neurons, and three additional subclusters. We then applied a recently described coaccessibility framework, Cicero, which identified 146,818 links between promoters and putative distal regulatory DNA. Identified coaccessibility networks showed cell-type specificity, shedding light on key dynamic loci that reconfigure to specify hippocampal cell lineages. Lastly, we performed an additional sci-ATAC-seq preparation from cultured hippocampal neurons (899 high-quality cells, 43,532 mean unique reads) that revealed substantial alterations in their epigenetic landscape compared with nuclei from hippocampal tissue. This data set and accompanying analysis tools provide a new resource that can guide subsequent studies of the hippocampus.


Assuntos
Cromatina/genética , Hipocampo/metabolismo , Células Piramidais/metabolismo , Animais , Linhagem da Célula/genética , Núcleo Celular/genética , Núcleo Celular/metabolismo , Células Cultivadas , Cromatina/metabolismo , Epigenômica/métodos , Camundongos , Plasticidade Neuronal/genética , Células Piramidais/citologia , Análise de Sequência de DNA , Análise de Célula Única/métodos , Transposases/genética , Transposases/metabolismo
19.
Neuron ; 102(1): 48-59, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30946825

RESUMO

Addiction is a disease in which, after a period of recreational use, a subset of individuals develops compulsive use that does not stop even in light of major negative consequences. Here, we review the evidence for underlying epigenetic remodeling in brain in two settings. First, excessive dopamine signaling during drug use may modulate gene expression, altering synaptic function and circuit activity and leading over time to maladaptive behaviors in vulnerable individuals. Second, on a longer timescale, life experience can shape the epigenetic landscape in brain and thereby may contribute to an individual's vulnerability by amplifying drug-induced changes in gene expression that drive the transition to addiction. We conclude by exploring how epigenetic mechanisms might serve as therapeutic targets for addiction treatments.


Assuntos
Encéfalo/metabolismo , Epigênese Genética/genética , Plasticidade Neuronal/genética , Transtornos Relacionados ao Uso de Substâncias/genética , Sinapses/genética , Transmissão Sináptica/genética , Animais , Variação Biológica Individual , Encéfalo/fisiopatologia , Cromatina/metabolismo , Humanos , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Sinapses/metabolismo
20.
Mol Neurobiol ; 56(10): 6883-6900, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30941732

RESUMO

Cerebral palsy (CP) is one of the most common childhood-onset motor disabilities, attributed to injuries of the immature brain in the foetal or early postnatal period. The underlying mechanisms are poorly understood, rendering prevention and treatment strategies challenging. The aim of the present study was to establish a mouse model of CP for preclinical assessment of new interventions. For this purpose, we explored the impact of a double neonatal insult (i.e. systemic inflammation combined with hypoxia) on behavioural and cellular outcomes relevant to CP during the prepubertal to adolescent period of mice. Pups were subjected to intraperitoneal lipopolysaccharide (LPS) injections from postnatal day (P) 3 to P6 followed by hypoxia at P7. Gene expression analysis at P6 revealed a strong inflammatory response in a brain region-dependent manner. A comprehensive battery of behavioural assessments performed between P24 and P47 showed impaired limb placement and coordination when walking on a horizontal ladder in both males and females. Exposed males also displayed impaired performance on a forelimb skilled reaching task, altered gait pattern and increased exploratory activity. Exposed females showed a reduction in grip strength and traits of anxiety-like behaviour. These behavioural alterations were not associated with gross morphological changes, white matter lesions or chronic inflammation in the brain. Our results indicate that the neonatal double-hit with LPS and hypoxia can induce subtle long-lasting deficits in motor learning and fine motor skills, which partly reflect the symptoms of children with CP who have mild gross and fine motor impairments.


Assuntos
Paralisia Cerebral/etiologia , Hipóxia-Isquemia Encefálica/complicações , Inflamação/complicações , Animais , Animais Recém-Nascidos , Ansiedade/complicações , Comportamento Animal , Encéfalo/patologia , Encéfalo/fisiopatologia , Paralisia Cerebral/fisiopatologia , Feminino , Marcha/fisiologia , Regulação da Expressão Gênica , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/patologia , Inflamação/genética , Inflamação/patologia , Aprendizagem , Lipopolissacarídeos , Masculino , Camundongos Endogâmicos C57BL , Microglia/patologia , Atividade Motora , Força Muscular/fisiologia , Plasticidade Neuronal/genética , Fenótipo , Caracteres Sexuais , Sinapses/metabolismo
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