Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.400
Filtrar
1.
Int J Mol Sci ; 22(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33808976

RESUMO

The mammalian hippocampal dentate gyrus is a unique memory circuit in which a subset of neurons is continuously generated throughout the lifespan. Previous studies have shown that the dentate gyrus neuronal population can hold fear memory traces (i.e., engrams) and that adult-born neurons (ABNs) support this process. However, it is unclear whether ABNs themselves hold fear memory traces. Therefore, we analyzed ABN activity at a population level across a fear conditioning paradigm. We found that fear learning did not recruit a distinct ABN population. In sharp contrast, a completely different ABN population was recruited during fear memory retrieval. We further provide evidence that ABN population activity remaps over time during the consolidation period. These results suggest that ABNs support the establishment of a fear memory trace in a different manner to directly holding the memory. Moreover, this activity remapping process in ABNs may support the segregation of memories formed at different times. These results provide new insight into the role of adult neurogenesis in the mammalian memory system.


Assuntos
Consolidação da Memória/fisiologia , Memória/fisiologia , Neurogênese/genética , Neurônios/metabolismo , Animais , Condicionamento Psicológico , Giro Denteado/metabolismo , Giro Denteado/fisiologia , Medo/fisiologia , Hipocampo/metabolismo , Hipocampo/fisiologia , Humanos , Aprendizagem/fisiologia , Camundongos , Neurônios/fisiologia
2.
J Affect Disord ; 286: 204-212, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33740637

RESUMO

INTRODUCTION: Attenuated adult hippocampal neurogenesis may manifest in affective symptomatology and/or resistance to antidepressant treatment. While early-life adversity and the short variant ('s') of the serotonin transporter gene's long polymorphic region (5-HTTLPR) are suggested as interacting risk factors for affective disorders, no studies have examined whether their superposed risk effectuates neurogenic changes into adulthood. Similarly, it is not established whether reduced hippocampal volume in adolescence, variously identified as a marker and antecedent of affective disorders, anticipates diminished adult neurogenesis. We investigate these potential developmental precursors of neurogenic alterations using a bonnet macaque model. METHODS: Twenty-five male infant bonnet macaques were randomized to stressed [variable foraging demand (VFD)] or normative [low foraging demand (LFD)] rearing protocols and genotyped for 5-HTTLPR polymorphisms. Adolescent MRI brain scans (mean age 4.2y) were available for 14 subjects. Adult-born neurons were detected post-mortem (mean age 8.6y) via immunohistochemistry targeting the microtubule protein doublecortin (DCX). Models were adjusted for age and weight. RESULTS: A putative vulnerability group (VG) of VFD-reared 's'-carriers (all 's/l') exhibited reduced neurogenesis compared to non-VG subjects. Neurogenesis levels were positively predicted by ipsilateral hippocampal volume normalized for total brain volume, but not by contralateral or raw hippocampal volume. LIMITATIONS: No 's'-carriers were identified in LFD-reared subjects, precluding a 2×2 factorial analysis. CONCLUSION: The 's' allele (with adverse rearing) and low adolescent hippocampal volume portend a neurogenic deficit in adult macaques, suggesting persistent alterations in hippocampal plasticity may contribute to these developmental factors' affective risk in humans.


Assuntos
Experiências Adversas da Infância , Proteínas da Membrana Plasmática de Transporte de Serotonina , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Hipocampo/diagnóstico por imagem , Hipocampo/metabolismo , Humanos , Macaca/metabolismo , Masculino , Neurogênese/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Estresse Psicológico/genética
3.
Nat Commun ; 12(1): 1828, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33758195

RESUMO

DNA sequences containing consecutive guanines organized in 4-interspaced tandem repeats can form stable single-stranded secondary structures, called G-quadruplexes (G4). Herein, we report that the Polycomb group protein BMI1 is enriched at heterochromatin regions containing putative G4 DNA sequences, and that G4 structures accumulate in cells with reduced BMI1 expression and/or relaxed chromatin, including sporadic Alzheimer's disease (AD) neurons. In AD neurons, G4 structures preferentially accumulate in lamina-associated domains, and this is rescued by re-establishing chromatin compaction. ChIP-seq analyses reveal that G4 peaks correspond to evolutionary conserved Long Interspersed Element-1 (L1) sequences predicted to be transcriptionally active. Hence, G4 structures co-localize with RNAPII, and inhibition of transcription can reverse the G4 phenotype without affecting chromatin's state, thus uncoupling both components. Intragenic G4 structures affecting splicing events are furthermore associated with reduced neuronal gene expression in AD. Active L1 sequences are thus at the origin of most G4 structures observed in human neurons.


Assuntos
Doença de Alzheimer/metabolismo , Eucromatina/metabolismo , Quadruplex G , Elementos Nucleotídeos Longos e Dispersos/genética , Neurogênese/genética , Neurônios/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Doença de Alzheimer/genética , Animais , Células Cultivadas , Sequenciamento de Cromatina por Imunoprecipitação , Eucromatina/genética , Feminino , Imunofluorescência , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Ontologia Genética , Heterocromatina/genética , Heterocromatina/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Pluripotentes/metabolismo , Complexo Repressor Polycomb 1/genética , Processamento de RNA/genética
4.
Neuron ; 109(5): 743-745, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33662268

RESUMO

Willsey et al. dissect phenotypes associated with in vivo disruption of ten ASD-associated genes using a hypothesis-free, parallelized approach in Xenopus tropicalis. These studies continue to implicate cortical neurons in ASD pathogenesis and suggest a convergence on functions related to neurogenesis.


Assuntos
Transtorno Autístico , Animais , Estrogênios , Neurogênese/genética , Xenopus , Xenopus laevis
5.
Nat Genet ; 53(3): 304-312, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33664506

RESUMO

Studying the function of common genetic variants in primary human tissues and during development is challenging. To address this, we use an efficient multiplexing strategy to differentiate 215 human induced pluripotent stem cell (iPSC) lines toward a midbrain neural fate, including dopaminergic neurons, and use single-cell RNA sequencing (scRNA-seq) to profile over 1 million cells across three differentiation time points. The proportion of neurons produced by each cell line is highly reproducible and is predictable by robust molecular markers expressed in pluripotent cells. Expression quantitative trait loci (eQTL) were characterized at different stages of neuronal development and in response to rotenone-induced oxidative stress. Of these, 1,284 eQTL colocalize with known neurological trait risk loci, and 46% are not found in the Genotype-Tissue Expression (GTEx) catalog. Our study illustrates how coupling scRNA-seq with long-term iPSC differentiation enables mechanistic studies of human trait-associated genetic variants in otherwise inaccessible cell states.


Assuntos
Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/fisiologia , Células-Tronco Pluripotentes Induzidas/citologia , Locos de Características Quantitativas , Transcriptoma , Diferenciação Celular/genética , Predisposição Genética para Doença , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Neurogênese/genética , Estresse Oxidativo/efeitos dos fármacos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Rotenona/toxicidade , Análise de Sequência de RNA , Análise de Célula Única
6.
Nat Commun ; 12(1): 1624, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712610

RESUMO

Adult Schwann cells (SCs) possess an inherent plastic potential. This plasticity allows SCs to acquire repair-specific functions essential for peripheral nerve regeneration. Here, we investigate whether stromal SCs in benign-behaving peripheral neuroblastic tumors adopt a similar cellular state. We profile ganglioneuromas and neuroblastomas, rich and poor in SC stroma, respectively, and peripheral nerves after injury, rich in repair SCs. Indeed, stromal SCs in ganglioneuromas and repair SCs share the expression of nerve repair-associated genes. Neuroblastoma cells, derived from aggressive tumors, respond to primary repair-related SCs and their secretome with increased neuronal differentiation and reduced proliferation. Within the pool of secreted stromal and repair SC factors, we identify EGFL8, a matricellular protein with so far undescribed function, to act as neuritogen and to rewire cellular signaling by activating kinases involved in neurogenesis. In summary, we report that human SCs undergo a similar adaptive response in two patho-physiologically distinct situations, peripheral nerve injury and tumor development.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular/fisiologia , Família de Proteínas EGF/genética , Família de Proteínas EGF/metabolismo , Neurogênese/fisiologia , Células de Schwann/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular , Plasticidade Celular/fisiologia , Proliferação de Células , Técnicas de Cocultura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regeneração Nervosa , Neuroblastoma/patologia , Neurogênese/genética , Traumatismos dos Nervos Periféricos , Transcriptoma , Adulto Jovem
7.
Nat Commun ; 12(1): 1174, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608552

RESUMO

Adult hippocampal neurogenesis contributes to learning and memory, and is sensitive to a variety of environmental stimuli. Exposure to a hypomagnetic field (HMF) influences the cognitive processes of various animals, from insects to human beings. However, whether HMF exposure affect adult hippocampal neurogenesis and hippocampus-dependent cognitions is still an enigma. Here, we showed that male C57BL/6 J mice exposed to HMF by means of near elimination of the geomagnetic field (GMF) exhibit significant impairments of adult hippocampal neurogenesis and hippocampus-dependent learning, which is strongly correlated with a reduction in the content of reactive oxygen species (ROS). However, these deficits seen in HMF-exposed mice could be rescued either by elevating ROS levels through pharmacological inhibition of ROS removal or by returning them back to GMF. Therefore, our results suggest that GMF plays an important role in adult hippocampal neurogenesis through maintaining appropriate endogenous ROS levels.


Assuntos
Cognição/fisiologia , Cognição/efeitos da radiação , Hipocampo/patologia , Hipocampo/efeitos da radiação , Campos Magnéticos/efeitos adversos , Neurogênese/fisiologia , Neurogênese/efeitos da radiação , Adulto , Animais , Proliferação de Células , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Aprendizagem , Masculino , Memória , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais , Neurogênese/genética , Espécies Reativas de Oxigênio
8.
Gene ; 781: 145528, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33631250

RESUMO

BACKGROUND: Spinal cord injury (SCI) leads to severe motor and sensory dysfunctions. Neural stem cells (NSCs) transplantation therapy plays a positive role in functional recovery after SCI, but the effectiveness of this therapy is limited by inadequate differentiation ability of transplanted NSCs. Mammalian achaete-scute homologue-1 (Mash-1) has been reported to improve differentiation of NSCs. Thus, this study modified NSCs with Mash-1 to repair SCI. METHODS: NSCs isolated from rat embryo hippocampus were cultured and identified in vitro and further transfected with the lentiviral vectors (Lv-Mash-1). After establishing a SCI rat model, the rats were transplanted with Mash-1 modified NSCs, the histopathological changes of rat spinal cord were detected by hematoxylin-eosin (HE) staining, and the locomotor activity of rats was evaluated with the Basso, Beattie and Bresnahan (BBB) scale. The NSCs cultured in vitro or extracted from SCI rat spinal cord were identified by immunofluorescence (IF). Mash-1, ß3-Tubulin, and NeuN expressions in those cells were determined by Western blotting and reverse transcription­quantitative polymerase chain reaction (RT­qPCR). RESULTS: NSCs isolated from rat embryo hippocampus were Nestin- and NeuN-positive. NSC transplantation modified by Mash-1 increased BBB score of SCI rats and promoted recovery in lesion site of SCI rats. Mash-1 overexpression also promoted ß3-Tubulin and NeuN expressions in NSCs cultured in vitro or extracted from spinal cord of SCI rats. CONCLUSION: Mash-1 overexpression promoted NSC differentiation into neurons, and further improved locomotor functional recovery of SCI rats.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Células-Tronco Neurais/transplante , Neurogênese , Traumatismos da Medula Espinal/terapia , Animais , Antígenos Nucleares/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/uso terapêutico , Células Cultivadas , Feminino , Locomoção , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Transfecção , Tubulina (Proteína)/metabolismo
9.
Science ; 371(6527)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33479124

RESUMO

The cerebral cortex is an intricate structure that controls human features such as language and cognition. Cortical functions rely on specialized neurons that emerge during development from complex molecular and cellular interactions. Neurodevelopmental disorders occur when one or several of these steps is incorrectly executed. Although a number of causal genes and disease phenotypes have been identified, the sequence of events linking molecular disruption to clinical expression mostly remains obscure. Here, focusing on human malformations of cortical development, we illustrate how complex interactions at the genetic, cellular, and circuit levels together contribute to diversity and variability in disease phenotypes. Using specific examples and an online resource, we propose that a multilevel assessment of disease processes is key to identifying points of vulnerability and developing new therapeutic strategies.


Assuntos
Córtex Cerebral/anormalidades , Transtornos Mentais/metabolismo , Doenças do Sistema Nervoso/metabolismo , Neurogênese/fisiologia , Neurônios/fisiologia , Animais , Comportamento , Movimento Celular/genética , Movimento Celular/fisiologia , Córtex Cerebral/metabolismo , Córtex Cerebral/ultraestrutura , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Transtornos Mentais/genética , Camundongos , Doenças do Sistema Nervoso/genética , Vias Neurais/anormalidades , Vias Neurais/metabolismo , Vias Neurais/ultraestrutura , Neurogênese/genética , Neurônios/citologia , Especificidade de Órgãos/genética , Especificidade de Órgãos/fisiologia
10.
Nucleic Acids Res ; 49(4): 2027-2043, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33476374

RESUMO

Dysfunction of splicing factors often result in abnormal cell differentiation and apoptosis, especially in neural tissues. Mutations in pre-mRNAs processing factor 31 (PRPF31) cause autosomal dominant retinitis pigmentosa, a progressive retinal degeneration disease. The transcriptome-wide splicing events specifically regulated by PRPF31 and their biological roles in the development and maintenance of retina are still unclear. Here, we showed that the differentiation and viability of retinal progenitor cells (RPCs) are severely perturbed in prpf31 knockout zebrafish when compared with other tissues at an early embryonic stage. At the cellular level, significant mitotic arrest and DNA damage were observed. These defects could be rescued by the wild-type human PRPF31 rather than the disease-associated mutants. Further bioinformatic analysis and experimental verification uncovered that Prpf31 deletion predominantly causes the skipping of exons with a weak 5' splicing site. Moreover, genes necessary for DNA repair and mitotic progression are most enriched among the differentially spliced events, which may explain the cellular and tissular defects in prpf31 mutant retinas. This is the first time that Prpf31 is demonstrated to be essential for the survival and differentiation of RPCs during retinal neurogenesis by specifically modulating the alternative splicing of genes involved in DNA repair and mitosis.


Assuntos
Processamento Alternativo , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Retina/embriologia , Proteínas de Peixe-Zebra/fisiologia , Animais , Apoptose , Sistemas CRISPR-Cas , Sobrevivência Celular , Dano ao DNA , Reparo do DNA , Éxons , Técnicas de Inativação de Genes , Pontos de Checagem da Fase M do Ciclo Celular , Células-Tronco Neurais/citologia , Neurônios Retinianos/citologia , Neurônios Retinianos/metabolismo , Fuso Acromático/ultraestrutura , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
11.
Nat Commun ; 12(1): 662, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510165

RESUMO

Dynamic assembly and disassembly of primary cilia controls embryonic development and tissue homeostasis. Dysregulation of ciliogenesis causes human developmental diseases termed ciliopathies. Cell-intrinsic regulatory mechanisms of cilia disassembly have been well-studied. The extracellular cues controlling cilia disassembly remain elusive, however. Here, we show that lysophosphatidic acid (LPA), a multifunctional bioactive phospholipid, acts as a physiological extracellular factor to initiate cilia disassembly and promote neurogenesis. Through systematic analysis of serum components, we identify a small molecular-LPA as the major driver of cilia disassembly. Genetic inactivation and pharmacological inhibition of LPA receptor 1 (LPAR1) abrogate cilia disassembly triggered by serum. The LPA-LPAR-G-protein pathway promotes the transcription and phosphorylation of cilia disassembly factors-Aurora A, through activating the transcription coactivators YAP/TAZ and calcium/CaM pathway, respectively. Deletion of Lpar1 in mice causes abnormally elongated cilia and decreased proliferation in neural progenitor cells, thereby resulting in defective neurogenesis. Collectively, our findings establish LPA as a physiological initiator of cilia disassembly and suggest targeting the metabolism of LPA and the LPA pathway as potential therapies for diseases with dysfunctional ciliogenesis.


Assuntos
Cílios/efeitos dos fármacos , Lisofosfolipídeos/farmacologia , Neurogênese/efeitos dos fármacos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Transdução de Sinais , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cílios/genética , Cílios/metabolismo , Células HEK293 , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Humanos , Lisofosfolipídeos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Ligação Proteica , Interferência de RNA , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismo
12.
Hum Genet ; 140(5): 791-803, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33392778

RESUMO

PIGK gene, encoding a key component of glycosylphosphatidylinositol (GPI) transamidase, was recently reported to be associated with inherited GPI deficiency disorders (IGDs). However, little is known about the specific downstream effects of PIGK on neurodevelopment due to the rarity of the disease and the lack of in vivo study. Here, we described 2 patients in a Chinese family presented with profound global developmental delay, severe hypotonia, seizures, and postnatal progressive global brain atrophy including hemisphere, cerebellar and corpus callosum atrophy. Two novel compound heterozygous variants in PIGK were identified via genetic analysis, which was proved to cause significant decrease of PIGK protein and reduced cell surface presence of GPI-APs in the patients. To explore the role of Pigk on embryonic and neuronal development, we constructed Pigk knock-down zebrafish and knock-in mouse models. Zebrafish injected with a small dose of morpholino oligonucleotides displayed severe developmental defects including small eyes, deformed head, curly spinal cord, and unconsumed yolk sac. Primary motor neuronal dysplasia and extensive neural cell apoptosis were further observed. Meanwhile, the mouse models, carrying the two variants respectively homologous with the patients, both resulted in complete embryonic lethality of the homozygotes, which suggested the intolerable effect caused by amino acid substitution of Asp204 as well as the truncated mutation. Our findings provide the in vivo evidence for the essential role of PIGK during the embryonic and neuronal development. Based on these data, we propose a basis for further study of pathological and molecular mechanisms of PIGK-related neurodevelopmental defects.


Assuntos
Encefalopatias/genética , Moléculas de Adesão Celular/genética , Glicosilfosfatidilinositóis/deficiência , Malformações do Sistema Nervoso/genética , Neurogênese/genética , Convulsões/genética , Anormalidades Múltiplas/genética , Animais , Apoptose/genética , Linhagem Celular , Pré-Escolar , Modelos Animais de Doenças , Desenvolvimento Embrionário/genética , Técnicas de Introdução de Genes , Glicosilfosfatidilinositóis/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Peixe-Zebra
13.
Nucleic Acids Res ; 49(3): 1345-1363, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33434264

RESUMO

Enhancers play important roles in controlling gene expression in a choreographed spatial and temporal manner during development. However, it is unclear how these regulatory regions are established during differentiation. Here we investigated the genome-wide binding profile of the forkhead transcription factor FOXK2 in human embryonic stem cells (ESCs) and downstream cell types. This transcription factor is bound to thousands of regulatory regions in human ESCs, and binding at many sites is maintained as cells differentiate to mesendodermal and neural precursor cell (NPC) types, alongside the emergence of new binding regions. FOXK2 binding is generally associated with active histone marks in any given cell type. Furthermore newly acquired, or retained FOXK2 binding regions show elevated levels of activating histone marks following differentiation to NPCs. In keeping with this association with activating marks, we demonstrate a role for FOXK transcription factors in gene activation during NPC differentiation. FOXK2 occupancy in ESCs is therefore an early mark for delineating the regulatory regions, which become activated in later lineages.


Assuntos
Diferenciação Celular/genética , Células-Tronco Embrionárias/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Ativação Transcricional , Linhagem da Célula/genética , Células Cultivadas , Cromatina/metabolismo , Células-Tronco Embrionárias/citologia , Endoderma/citologia , Elementos Facilitadores Genéticos , Código das Histonas , Humanos , Mesoderma/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Fatores de Transcrição/metabolismo
14.
Mol Cell ; 81(2): 304-322.e16, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33357414

RESUMO

Protein synthesis must be finely tuned in the developing nervous system as the final essential step of gene expression. This study investigates the architecture of ribosomes from the neocortex during neurogenesis, revealing Ebp1 as a high-occupancy 60S peptide tunnel exit (TE) factor during protein synthesis at near-atomic resolution by cryoelectron microscopy (cryo-EM). Ribosome profiling demonstrated Ebp1-60S binding is highest during start codon initiation and N-terminal peptide elongation, regulating ribosome occupancy of these codons. Membrane-targeting domains emerging from the 60S tunnel, which recruit SRP/Sec61 to the shared binding site, displace Ebp1. Ebp1 is particularly abundant in the early-born neural stem cell (NSC) lineage and regulates neuronal morphology. Ebp1 especially impacts the synthesis of membrane-targeted cell adhesion molecules (CAMs), measured by pulsed stable isotope labeling by amino acids in cell culture (pSILAC)/bioorthogonal noncanonical amino acid tagging (BONCAT) mass spectrometry (MS). Therefore, Ebp1 is a central component of protein synthesis, and the ribosome TE is a focal point of gene expression control in the molecular specification of neuronal morphology during development.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Neocórtex/metabolismo , Neurônios/metabolismo , Biossíntese de Proteínas , Proteostase/genética , Proteínas de Ligação a RNA/genética , Subunidades Ribossômicas Maiores de Eucariotos/genética , Animais , Animais Recém-Nascidos , Sítios de Ligação , Moléculas de Adesão Celular Neuronais/química , Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/metabolismo , Linhagem Celular Tumoral , Microscopia Crioeletrônica , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Embrião de Mamíferos , Feminino , Masculino , Camundongos , Neocórtex/citologia , Neocórtex/crescimento & desenvolvimento , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Neurônios/citologia , Cultura Primária de Células , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/ultraestrutura , Partícula de Reconhecimento de Sinal/química , Partícula de Reconhecimento de Sinal/genética , Partícula de Reconhecimento de Sinal/metabolismo
15.
Methods Mol Biol ; 2239: 77-100, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33226614

RESUMO

MicroRNAs (miRNAs), miR-9/9*, and miR-124 (miR-9/9*-124) display fate-reprogramming activities when ectopically expressed in human fibroblasts by erasing the fibroblast identity and evoking a pan-neuronal state. In contrast to induced pluripotent stem cell-derived neurons, miRNA-induced neurons (miNs) retain the biological age of the starting fibroblasts through direct fate conversion and thus provide a human neuron-based platform to study cellular properties inherent in aged neurons and model adult-onset neurodegenerative disorders using patient-derived cells. Furthermore, expression of neuronal subtype-specific transcription factors in conjunction with miR-9/9*-124 guides the miNs to distinct neuronal fates, a feature critical for modeling disorders that affect specific neuronal subtypes. Here, we describe the miR-9/9*-124-based neuronal reprogramming protocols for the generation of several disease-relevant neuronal subtypes: striatal medium spiny neurons, cortical neurons, and spinal cord motor neurons.


Assuntos
Reprogramação Celular/genética , MicroRNAs/metabolismo , Neurônios Motores/citologia , Neurogênese/genética , Fatores de Transcrição/metabolismo , Linhagem Celular , Células Cultivadas , Senescência Celular/genética , Corpo Estriado/citologia , Corpo Estriado/metabolismo , Meios de Cultura/química , Fibroblastos/citologia , Fibroblastos/metabolismo , Vetores Genéticos , Humanos , Lentivirus/genética , MicroRNAs/genética , Neurônios Motores/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Medula Espinal/citologia , Medula Espinal/metabolismo , Fatores de Transcrição/genética
16.
Aging (Albany NY) ; 13(2): 2330-2347, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33318303

RESUMO

In the mammalian brain, alternative pre-mRNA splicing is a fundamental mechanism that modifies neuronal function dynamically where secretion of different splice variants regulates neurogenesis, development, pathfinding, maintenance, migration, and synaptogenesis. Sequence-specific RNA-Binding Protein CPEB3 has distinctive isoform-distinct biochemical interactions and neuronal development assembly roles. Nonetheless, the mechanisms moderating splice isoform options remain unclear. To establish the modulatory trend of CPEB3, we cloned and excessively expressed CPEB3 in HT22 cells. We used RNA-seq to analyze CPEB3-regulated alternative splicing on control and CPEB3-overexpressing cells. Consequently, we used iRIP-seq to identify CPEB-binding targets. We additionally validated CPEB3-modulated genes using RT-qPCR. CPEB3 overexpression had insignificant effects on gene expression in HT22 cells. Notably, CPEB3 partially modulated differential gene splicing enhanced in the modulation of neural development, neuron cycle, neurotrophin, synapse, and specific development pathway, implying an alternative splicing regulatory mechanism associated with neurogenesis. Moreover, qRT-PCR verified the CPEB3-modulated transcription of neurogenesis genes LCN2 and NAV2, synaptogenesis gene CYLD, as well as neural development gene JADE1. Herein, we established that CPEB3 is a critical modulator of alternative splicing in neurogenesis, which remarkably enhances the current understanding of the CPEB3 mediated alternative pre-mRNA splicing.


Assuntos
Processamento Alternativo/genética , Neurogênese/genética , Neurônios/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Linhagem Celular , Hipocampo/metabolismo , Camundongos , Processamento de RNA , Proteínas de Ligação a RNA/genética
17.
PLoS One ; 15(10): e0238578, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33001981

RESUMO

The spiral ganglion neurons constitute the primary connection between auditory hair cells and the brain. The spiral ganglion afferent fibers and their synapse with hair cells do not regenerate to any significant degree in adult mammalian ears after damage. We have investigated gene expression changes after kainate-induced disruption of the synapses in a neonatal cochlear explant model in which peripheral fibers and the afferent synapse do regenerate. We compared gene expression early after damage, during regeneration of the fibers and synapses, and after completion of in vitro regeneration. These analyses revealed a total of 2.5% differentially regulated transcripts (588 out of 24,000) based on a threshold of p<0.005. Inflammatory response genes as well as genes involved in regeneration of neural circuits were upregulated in the spiral ganglion neurons and organ of Corti, where the hair cells reside. Prominent genes upregulated at several time points included genes with roles in neurogenesis (Elavl4 and Sox21), neural outgrowth (Ntrk3 and Ppp1r1c), axonal guidance (Rgmb and Sema7a), synaptogenesis (Nlgn2 and Psd2), and synaptic vesicular function (Syt8 and Syn1). Immunohistochemical and in situ hybridization analysis of genes that had not previously been described in the cochlea confirmed their cochlear expression. The time course of expression of these genes suggests that kainate treatment resulted in a two-phase response in spiral ganglion neurons: an acute response consistent with inflammation, followed by an upregulation of neural regeneration genes. Identification of the genes activated during regeneration of these fibers suggests candidates that could be targeted to enhance regeneration in adult ears.


Assuntos
Células Ciliadas Auditivas/fisiologia , Regeneração Nervosa/genética , Regeneração Nervosa/fisiologia , Neurônios Aferentes/fisiologia , Animais , Animais Recém-Nascidos , Expressão Gênica/efeitos dos fármacos , Células Ciliadas Auditivas/efeitos dos fármacos , Inflamação/genética , Inflamação/fisiopatologia , Ácido Caínico/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Modelos Neurológicos , Neurogênese/genética , Neurogênese/fisiologia , Gânglio Espiral da Cóclea/citologia , Gânglio Espiral da Cóclea/fisiologia , Sinapses/fisiologia , Técnicas de Cultura de Tecidos
18.
Science ; 370(6512)2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33004487

RESUMO

Injuries to the central nervous system (CNS) are inefficiently repaired. Resident neural stem cells manifest a limited contribution to cell replacement. We have uncovered a latent potential in neural stem cells to replace large numbers of lost oligodendrocytes in the injured mouse spinal cord. Integrating multimodal single-cell analysis, we found that neural stem cells are in a permissive chromatin state that enables the unfolding of a normally latent gene expression program for oligodendrogenesis after injury. Ectopic expression of the transcription factor OLIG2 unveiled abundant stem cell-derived oligodendrogenesis, which followed the natural progression of oligodendrocyte differentiation, contributed to axon remyelination, and stimulated functional recovery of axon conduction. Recruitment of resident stem cells may thus serve as an alternative to cell transplantation after CNS injury.


Assuntos
Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Oligodendroglia/fisiologia , Regeneração da Medula Espinal/fisiologia , Animais , Astrócitos/fisiologia , Axônios/fisiologia , Linhagem da Célula , Epêndima/citologia , Epêndima/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurogênese/genética , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Oligodendroglia/citologia , Recuperação de Função Fisiológica/genética , Recuperação de Função Fisiológica/fisiologia , Remielinização/genética , Remielinização/fisiologia , Análise de Célula Única , Traumatismos da Medula Espinal/fisiopatologia , Regeneração da Medula Espinal/genética
19.
Med Sci (Paris) ; 36(10): 866-871, 2020 Oct.
Artigo em Francês | MEDLINE | ID: mdl-33026328

RESUMO

Pathogenic variants of the gene NDE1 (Nuclear Distribution Element 1) in humans lead to microlissencephaly which associates a reduced head circumference and a simplified gyration. Microlissencephaly is the most severe deficit of neurogenesis described to date but its precise physiopathological mechanism is not yet well known. The NDE1 gene encodes a phosphoprotein that is essential to neurogenesis and that is expressed in various cell compartments of neuroblasts. More than 60 interaction partners with NDE1 have been reported, notably various proteins involved in formation of the mitotic spindle, in ciliation, in genome protection of dividing neuroblasts or even in apoptosis (like LIS1, dynein or cohesin), which are all avenues that we explore in this review.


Assuntos
Encéfalo/embriologia , Microcefalia/genética , Proteínas Associadas aos Microtúbulos/genética , Neurogênese/genética , Encéfalo/crescimento & desenvolvimento , Humanos , Microcefalia/patologia , Mitose/genética , Células-Tronco Neurais/fisiologia
20.
Science ; 369(6510)2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32943498

RESUMO

Although many molecular mechanisms controlling developmental processes are evolutionarily conserved, the speed at which the embryo develops can vary substantially between species. For example, the same genetic program, comprising sequential changes in transcriptional states, governs the differentiation of motor neurons in mouse and human, but the tempo at which it operates differs between species. Using in vitro directed differentiation of embryonic stem cells to motor neurons, we show that the program runs more than twice as fast in mouse as in human. This is not due to differences in signaling, nor the genomic sequence of genes or their regulatory elements. Instead, there is an approximately two-fold increase in protein stability and cell cycle duration in human cells compared with mouse cells. This can account for the slower pace of human development and suggests that differences in protein turnover play a role in interspecies differences in developmental tempo.


Assuntos
Desenvolvimento Embrionário/fisiologia , Neurônios Motores/fisiologia , Neurogênese/fisiologia , Estabilidade Proteica , Animais , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Masculino , Neurônios Motores/citologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Tubo Neural/embriologia , Neurogênese/genética , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...