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1.
Cell Death Differ ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015502

RESUMO

Angiogenesis plays crucial roles in maintaining the complex operation of central nervous system (CNS) development. The architecture of communication between neurogenesis and angiogenesis is essential to maintain normal brain development and function. Hence, any disruption of neuron-vascular communications may lead to the pathophysiology of cerebrovascular diseases and blood-brain barrier (BBB) dysfunction. Here we demonstrate that neural differentiation and communication are required for vascular development. Regarding the cellular and molecular mechanism, our results show that PRDM16 activity determines the production of mature neurons and their specific positions in the neocortex. In the cortical plate (CP), aberrant neurons fail to secrete modular calcium-binding protein 1 (SMOC1), an important neuronal signal that participates in neurovascular communication to regulate CNS angiogenesis. Neuronal SMOC1 interacts with TGFBR1 by activating the transcription factors phospho-Smad2/3 to convey intercellular signals to endothelial cells (ECs) in the TGF-ß-Smad signaling pathway. Together, our results highlight a crucial coordinated neurovascular development process orchestrated by PRDM16 and reveal the importance of intimate communication for building the neurovascular network during brain development.

2.
Sci Adv ; 6(1): eaay6350, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31911949

RESUMO

Temperature homeostasis is critical for fetal development. The heat sensor protein TRPM2 (transient receptor potential channel M2) plays crucial roles in the heat response, but its function and specific mechanism in brain development remain largely unclear. Here, we observe that TRPM2 is expressed in neural stem cells. In hyperthermia, TRPM2 knockdown and knockout reduce the proliferation of neural progenitor cells (NPCs) and, accordingly, increase premature cortical neuron differentiation. In terms of the mechanism, TRPM2 regulates neural progenitor self-renewal by targeting SP5 (specificity protein 5) via inhibiting the phosphorylation of ß-catenin and increasing ß-catenin expression. Furthermore, the constitutive expression of TRPM2 or SP5 partly rescues defective NPC proliferation in the TRPM2-deficient embryonic brain. Together, the data suggest that TRPM2 has a critical function in maintaining the NPC pool during heat stress, and the findings provide a framework for understanding how the disruption of the TRPM2 gene may contribute to neurological disorders.

3.
J Genet Genomics ; 46(10): 459-465, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31771824

RESUMO

Identifying approaches for treating neurodegeneration is a thorny task but is important for a growing number of patients. Researchers have focused on discovering the underlying molecular mechanisms of reprogramming and optimizing the technologies for acquiring neurons. Direct conversion is one of the most important processes for treating neurological disorders. Induced neurons derived from direct conversion, which bypass the pluripotency stage, are more effective, more quickly obtained, and are safer than those produced via induced pluripotent stem cells (iPSCs). Based on iPSC strategies, scientists have derived methods to obtain functional neurons by direct conversion, such as neuron-related transcriptional factors, small molecules, microRNAs, and epigenetic modifiers. In this review, we discuss the present strategies for direct conversion of somatic cells into functional neurons and the potentials of direct conversion for producing functional neurons and treating neurodegeneration.

4.
Proc Natl Acad Sci U S A ; 116(48): 24122-24132, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31712428

RESUMO

Microglia, the resident immune cells of the central nervous system, play an important role in the brain. Microglia have a special spatiotemporal distribution during the development of the cerebral cortex. Neural progenitor cells (NPCs) are the main source of neural-specific cells in the early brain. It is unclear whether NPCs affect microglial development and what molecular mechanisms control early microglial localization. H2A.Z.2, a histone variant of H2A, has a key role in gene expression regulation, genomic stability, and chromatin remodeling, but its function in brain development is not fully understood. Here, we found that the specific deletion of H2A.Z.2 in neural progenitor cells led to an abnormal increase in microglia in the ventricular zone/subventricular zone (VZ/SVZ) of the embryonic cortex. Mechanistically, H2A.Z.2 regulated microglial development by incorporating G9a into the promoter region of Cxcl14 and promoted H3k9me2 modification to inhibit the transcription of Cxcl14 in neural progenitor cells. Meanwhile, we found that the deletion of H2A.Z.2 in microglia itself had no significant effect on microglial development in the early cerebral cortex. Our findings demonstrate a key role of H2A.Z.2 in neural progenitor cells in controlling microglial development and broaden our knowledge of 2 different types of cells that may affect each other through crosstalk in the central nervous system.

5.
Nucleic Acids Res ; 46(17): 8817-8831, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-29982651

RESUMO

Astrocytes play crucial roles in the central nervous system, and defects in astrocyte function are closely related to many neurological disorders. Studying the mechanism of gliogenesis has important implications for understanding and treating brain diseases. Epigenetic regulations have essential roles during mammalian brain development. Here, we demonstrate that histone H2A.Z.1 is necessary for the specification of multiple neural precursor cells (NPCs) and has specialized functions that regulate gliogenesis. Depletion of H2A.Z.1 suppresses gliogenesis and results in reduced astrocyte differentiation. Additionally, H2A.Z.1 regulates the acetylation of H3K56 (H3K56ac) by cooperating with the chaperone of ASF1a. Furthermore, RNA-seq data indicate that folate receptor 1 (FOLR1) participates in gliogenesis through the JAK-STAT signaling pathway. Taken together, our results demonstrate that H2A.Z.1 is a key regulator of gliogenesis because it interacts with ASF1a to regulate H3K56ac and then directly affects the expression of FOLR1, which acts as a signal-transducing component of the JAK-STAT signaling pathway.


Assuntos
Receptor 1 de Folato/genética , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Neurogênese/genética , Neuroglia/fisiologia , Acetilação , Animais , Astrócitos/fisiologia , Proteínas de Ciclo Celular , Células Cultivadas , Proteínas Cromossômicas não Histona/metabolismo , Embrião de Mamíferos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Histonas/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Chaperonas Moleculares , Células-Tronco Neurais , Gravidez , Transdução de Sinais/genética , Transcrição Genética
6.
J Cell Biol ; 217(10): 3464-3479, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30037926

RESUMO

In mammals, a constant body temperature is an important basis for maintaining life activities. Here, we show that when pregnant mice are subjected to cold stress, the expression of RBM3, a cold-induced protein, is increased in the embryonic brain. When RBM3 is knocked down or knocked out in cold stress, embryonic brain development is more seriously affected, exhibiting abnormal neuronal differentiation. By detecting the change in mRNA expression during maternal cold stress, we demonstrate that Yap and its downstream molecules are altered at the RNA level. By analyzing RNA-binding motif of RBM3, we find that there are seven binding sites in 3'UTR region of Yap1 mRNA. Mechanistically, RBM3 binds to Yap1-3'UTR, regulates its stability, and affects the expression of YAP1. RBM3 and YAP1 overexpression can partially rescue the brain development defect caused by RBM3 knockout in cold stress. Collectively, our data demonstrate that cold temperature affects brain development, and RBM3 acts as a key protective regulator in cold stress.


Assuntos
Regiões 3' não Traduzidas , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Encéfalo/embriologia , Resposta ao Choque Frio , Embrião de Mamíferos/embriologia , Neurogênese , Fosfoproteínas/biossíntese , Estabilidade de RNA , Proteínas de Ligação a RNA/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Ciclo Celular , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Motivos de Nucleotídeos , Fosfoproteínas/genética , Proteínas de Ligação a RNA/genética
7.
J Cell Biol ; 217(6): 2103-2119, 2018 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618492

RESUMO

Testosterone is indispensable for sexual development and maintaining male characteristics, and deficiency of this hormone results in primary or late-onset hypogonadism (LOH). Testosterone is primarily produced in Leydig cells, where autophagy has been reported to be extremely active. However, the functional role of autophagy in testosterone synthesis remains unknown. In this study, we show that steroidogenic cell-specific disruption of autophagy influenced the sexual behavior of aging male mice because of a reduction in serum testosterone, which is similar to the symptoms of LOH. The decline in testosterone was caused mainly by a defect in cholesterol uptake in autophagy-deficient Leydig cells. Further studies revealed that once autophagic flux was disrupted, Na+/H+ exchanger regulatory factor 2 (NHERF2) accumulated in Leydig cells, resulting in the down-regulation of scavenger receptor class B, type I (SR-BI) and eventually leading to insufficient cholesterol supply. Collectively, these results reveal that autophagy promotes cholesterol uptake into Leydig cells by eliminating NHERF2, suggesting that dysfunction of autophagy might be causal in the loss of testosterone production in some patients.


Assuntos
Autofagia , Colesterol/metabolismo , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Testosterona/biossíntese , Adulto , Sequência de Aminoácidos , Animais , Autofagia/efeitos dos fármacos , Proteínas Relacionadas à Autofagia/metabolismo , Antígenos CD36/metabolismo , Gonadotropina Coriônica/farmacologia , Regulação para Baixo/efeitos dos fármacos , Humanos , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Camundongos , Modelos Biológicos , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Comportamento Sexual Animal/efeitos dos fármacos , Trocadores de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/metabolismo , Testosterona/sangue , Adulto Jovem
8.
Stem Cell Reports ; 10(4): 1193-1207, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29551674

RESUMO

Neural stem cell (NSC) proliferation and differentiation in the developing brain is a complex process precisely regulated by intrinsic and extrinsic signals. Although epigenetic modification has been reportedly involved in the regulation of the cerebral cortex, whether UTX, an H3K27me3 demethylase, regulates the development of cerebral cortex during the embryonic period is unclear. In this study, we demonstrate that Utx deficiency by knockdown and conditional knockout increases NSC proliferation and decreases terminal mitosis and neuronal differentiation. Furthermore, we find that impairment of cortical development caused by lack of Utx is less significant in males than in females. In addition, UTX demethylates H3K27me3 at the Pten promoter and promotes Pten expression. P-AKT and P-mTOR levels are increased in the Utx conditional knockout cortices. Finally, Utx or Pten overexpression can rescue the impairment of brain development caused by Utx loss. These findings may provide important clues toward deciphering brain diseases.


Assuntos
Diferenciação Celular , Histona Desmetilases/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proteínas/metabolismo , Transdução de Sinais , Animais , Encéfalo/embriologia , Encéfalo/metabolismo , Ciclo Celular , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Histona Desmetilases/deficiência , Camundongos Endogâmicos ICR , Camundongos Knockout , Neurogênese , Fator de Transcrição PAX6/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
9.
Cell Rep ; 22(9): 2279-2293, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29490266

RESUMO

The precise function and role of nucleosome assembly protein 1-like 1 (Nap1l1) in brain development are unclear. Here, we find that Nap1l1 knockdown decreases neural progenitor cell (NPC) proliferation and induces premature neuronal differentiation during cortical development. A similar deficiency in embryonic neurogenesis was observed in Nap1l1 knockout (KO) mice, which were generated using the CRISPR-Cas9 system. RNA sequencing (RNA-seq) analysis indicates that Ras-associated domain family member 10 (RassF10) may be the downstream target of Nap1l1. Furthermore, we found that Nap1l1 regulates RassF10 expression by promoting SETD1A-mediated H3K4 trimethylation at the RassF10 promoter. Nap1l1 KO defects may be rescued by RassF10 overexpression, suggesting that Nap1l1 controls NPC differentiation through RassF10. Our findings reveal an essential role for the Nap1l1 histone chaperone in cortical neurogenesis during early embryonic brain development.


Assuntos
Encéfalo/citologia , Encéfalo/embriologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Proteína 1 de Modelagem do Nucleossomo/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Feminino , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Inativação Gênica , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Metilação , Camundongos Endogâmicos ICR , Camundongos Knockout , Mitose/genética , Neurogênese/genética , Proteína 1 de Modelagem do Nucleossomo/genética , Regiões Promotoras Genéticas
10.
Stem Cell Res Ther ; 9(1): 2, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29304842

RESUMO

BACKGROUND: Pluripotent stem cells hold great promise for regenerative medicine. However, before clinical application, reproducible protocols for pluripotent stem cell differentiation should be established. Extracellular signal-regulated protein kinase (ERK) signaling plays a central role for the self-renewal of epiblast stem cells (EpiSCs), but its role for subsequent germ layer differentiation is still ambiguous. We proposed that ERK could modulate differentiation of the epiblast. METHODS: PD0325901 was used to inhibit ERK activation during the differentiation of embryonic stem cells and EpiSCs. Immunofluorescence, western blot analysis, real-time PCR and flow cytometry were used to detect germ layer markers and pathway activation. RESULTS: We demonstrate that the ERK phosphorylation level is lower in neuroectoderm of mouse E7.5 embryos than that in the primitive streak. ERK inhibition results in neural lineage commitment of epiblast. Mechanistically, PD0325901 abrogates the expression of primitive streak markers by ß-catenin retention in the cytoplasm, and inhibits the expression of OCT4 and NANOG during EpiSC differentiation. Thus, EpiSCs differentiate into neuroectodermal lineage efficiently under PD0325901 treatment. These results suggest that neuroectoderm differentiation does not require extrinsic signals, supporting the default differentiation of neural lineage. CONCLUSIONS: We report that a single ERK inhibitor, PD0325901, can specify epiblasts and EpiSCs into neural-like cells, providing an efficient strategy for neural differentiation.


Assuntos
Células-Tronco Embrionárias/citologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Camadas Germinativas/citologia , Placa Neural/citologia , Neurogênese/fisiologia , Linha Primitiva/citologia , Animais , Benzamidas/farmacologia , Células Cultivadas , Difenilamina/análogos & derivados , Difenilamina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Homeobox Nanog/biossíntese , Placa Neural/metabolismo , Fator 3 de Transcrição de Octâmero/biossíntese , Fator 3 de Transcrição de Octâmero/genética , Fosforilação , Linha Primitiva/metabolismo , beta Catenina/metabolismo
11.
Nucleic Acids Res ; 46(5): 2290-2307, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29294103

RESUMO

Defects in neurogenesis alter brain circuit formations and may lead to neurodevelopmental disorders such as autism and schizophrenia. Histone H2A.z, a variant of histone H2A, plays critical roles in chromatin structure and epigenetic regulation, but its function and mechanism in brain development remain largely unknown. Here, we find that the deletion of H2A.z results in enhanced proliferation of neural progenitors but reduced neuronal differentiation. In addition, neurons in H2A.z knockout mice exhibit abnormal dendrites during brain development. Furthermore, H2A.zcKO mice exhibit serial behavioral deficits, such as decreased exploratory activity and impaired learning and memory. Mechanistically, H2A.z regulates embryonic neurogenesis by targeting Nkx2-4 through interaction with Setd2, thereby promoting H3K36me3 modification to activate the transcription of Nkx2-4. Furthermore, enforced expression of Nkx2-4 can rescue the defective neurogenesis in the H2A.z-knockdown embryonic brain. Together, our findings implicate the epigenetic regulation by H2A.z in embryonic neurogenesis and provide a framework for understanding how disruption in the H2A.z gene may contribute to neurological disorders.


Assuntos
Encéfalo/metabolismo , Deleção de Genes , Histonas/genética , Transtornos do Neurodesenvolvimento/genética , Neurogênese/genética , Especificidade de Órgãos/genética , Animais , Encéfalo/embriologia , Linhagem Celular Tumoral , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Perfilação da Expressão Gênica , Células HEK293 , Histonas/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Transtornos do Neurodesenvolvimento/metabolismo , Interferência de RNA
12.
Cell Death Differ ; 25(2): 294-306, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28984873

RESUMO

Astrocyte has crucial roles in the central nervous system and accumulating evidence has shown its core function for brain complexity, plasticity and cognition. However, the essential key factors in the precise regulation of astrocytic differentiation remain largely uncharacterized. Here, we identified that RNF20, an E3 ligase of H2BK120 in the mammalian system, regulates astrocyte production from neural precursor cells. RNF20 deficiency by shRNA knockdown or deletion in conditional knockout mice impairs the astrocytic differentiation. Overexpression of RNF20 promotes astrocytic differentiation and can rescue the astrocyte production deficiency caused by RNF20 disruption. Furthermore, we demonstrate that RNF20 functions cooperatively with acetyltransferase MOF to promote astrocytic generation. RNF20-mediated H2Bub1 cooperating with MOF-mediated H4K16ac activates the transcription of Stat3. Together, these data indicate RNF20 is a critical regulator of astrocytic production, which may contribute to the understanding of neurological disorders with glial dysgenesis.


Assuntos
Astrócitos/metabolismo , Encéfalo/metabolismo , Epigênese Genética/genética , Fator de Transcrição STAT3/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Diferenciação Celular , Camundongos , RNA Interferente Pequeno/farmacologia , Fator de Transcrição STAT3/genética , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/deficiência
13.
Cell Death Differ ; 24(10): 1672-1680, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28622295

RESUMO

Although much is known about transcriptional networks that control embryonic stem cell (ESC) self-renewal and differentiation, the metabolic regulation of ESC is less clear. Autophagy is a catabolic process that is activated under both stress and normal conditions to degrade damaged organelles and aggregated proteins, and thus plays pivotal roles in somatic and adult stem cell function. However, if and how ESCs harness autophagy to regulate stemness remains largely unknown. Recently, we have defined that autophagy is essential for mitochondrial homeostasis regulation in pluripotency acquirement and maintenance. Here we identified high autophagic flux as an essential mechanism to maintain ESC identity. We show that mouse ESCs exhibit a high autophagic flux that is maintained by coordinating expression of autophagy core molecular machinery genes through FOXO1, a forkhead family transcription factor. Tapering autophagic flux by manipulating either Atg3 or Foxo1 expression compromised ESC self-renewal, pluripotency, and differentiation that could be restored by gain of wild-type but not function-deficient Atg3 or Foxo1 mutants, respectively. Our results define a newly recognized role of autophagic flux in mouse ESC identity maintenance that links cellular catabolism to ESC fate regulation.


Assuntos
Autofagia/genética , Diferenciação Celular/genética , Proteína Forkhead Box O1/genética , Células-Tronco Embrionárias Murinas , Animais , Linhagem Celular , Autorrenovação Celular/genética , Regulação da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Pluripotentes/citologia
14.
J Biol Chem ; 292(31): 12959-12970, 2017 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-28500132

RESUMO

The zinc finger E-box-binding transcription factor Zeb1 plays a pivotal role in the epithelial-mesenchymal transition. Numerous studies have focused on the molecular mechanisms by which Zeb1 contributes to this process. However, the functions of Zeb1 beyond the epithelial-mesenchymal transition remain largely elusive. Using a transdifferentiation system to convert mouse embryonic fibroblasts (MEFs) into functional neurons via the neuronal transcription factors achaete-scute family bHLH (basic helix-loop-helix) transcription factor1 (Ascl1), POU class 3 homeobox 2 (POU3F2/Brn2), and neurogenin 2 (Neurog2, Ngn2) (ABN), we found that Zeb1 was up-regulated during the early stages of transdifferentiation. Knocking down Zeb1 dramatically attenuated the transdifferentiation efficiency, whereas Zeb1 overexpression obviously increased the efficiency of transdifferentiation from MEFs to neurons. Interestingly, Zeb1 improved the transdifferentiation efficiency induced by even a single transcription factor (e.g. Asc1 or Ngn2). Zeb1 also rapidly promoted the maturation of induced neuron cells to functional neurons and improved the formation of neuronal patterns and electrophysiological characteristics. Induced neuron cells could form functional synapse in vivo after transplantation. Genome-wide RNA arrays showed that Zeb1 overexpression up-regulated the expression of neuron-specific genes and down-regulated the expression of epithelial-specific genes during conversion. Taken together, our results reveal a new role for Zeb1 in the transdifferentiation of MEFs into neurons.


Assuntos
Transdiferenciação Celular , Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas do Tecido Nervoso/metabolismo , Neurogênese , Neurônios/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Células Cultivadas , Embrião de Mamíferos/citologia , Fibroblastos/citologia , Perfilação da Expressão Gênica , Vida Livre de Germes , Hipocampo , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Neurônios/citologia , Neurônios/transplante , Fatores do Domínio POU/genética , Fatores do Domínio POU/metabolismo , Interferência de RNA , Proteínas Recombinantes/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/antagonistas & inibidores , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
15.
J Cell Biol ; 216(7): 1975-1992, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28515277

RESUMO

Histone cell cycle regulator (HIRA) is a histone chaperone and has been identified as an epigenetic regulator. Subsequent studies have provided evidence that HIRA plays key roles in embryonic development, but its function during early neurogenesis remains unknown. Here, we demonstrate that HIRA is enriched in neural progenitor cells, and HIRA knockdown reduces neural progenitor cell proliferation, increases terminal mitosis and cell cycle exit, and ultimately results in premature neuronal differentiation. Additionally, we demonstrate that HIRA enhances ß-catenin expression by recruiting H3K4 trimethyltransferase Setd1A, which increases H3K4me3 levels and heightens the promoter activity of ß-catenin. Significantly, overexpression of HIRA, HIRA N-terminal domain, or ß-catenin can override neurogenesis abnormities caused by HIRA defects. Collectively, these data implicate that HIRA, cooperating with Setd1A, modulates ß-catenin expression and then regulates neurogenesis. This finding represents a novel epigenetic mechanism underlying the histone code and has profound and lasting implications for diseases and neurobiology.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proliferação de Células , Córtex Cerebral/metabolismo , Chaperonas de Histonas/metabolismo , Histonas/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese , Fatores de Transcrição/metabolismo , beta Catenina/metabolismo , Animais , Apoptose , Ciclo Celular , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Córtex Cerebral/embriologia , Metilação de DNA , Epigênese Genética , Idade Gestacional , Chaperonas de Histonas/genética , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Metilação , Camundongos Endogâmicos ICR , Mitose , Células-Tronco Neurais/patologia , Fenótipo , Cultura Primária de Células , Processamento de Proteína Pós-Traducional , Interferência de RNA , Transdução de Sinais , Fatores de Transcrição/genética , Transfecção , beta Catenina/genética
16.
Cell Death Differ ; 24(9): 1548-1563, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28524856

RESUMO

During the brain development, the process of neural stem cells (NSCs) proliferation and differentiation is precisely regulated. The deficiency in the embryonic brain development will cause serious developmental disorders. Epigenetic modifications play critical roles in controlling proliferation and differentiation in different types of stem cells. Histone variants, as one of epigenetic regulators, have been reported to be associated with many bioprocesses. Among different variants, H3.3 is one of the important epigenetic regulators, but its role in embryonic NSCs remains unclear. Here we demonstrate that H3.3 is intrinsically required for NSCs proliferation and differentiation. Suppression of the H3.3 mediated by shRNAs causes the reduction of the PAX6-positive NSCs proliferation, and promotes the premature terminal mitosis and neuronal differentiation. Particularly, the level of the H4K16ac is selectively reduced in the H3.3 knockdown NSCs. We further confirm that H3.3 is directly interacted with the MOF, a specific H4K16 acetyltransferase. Interestingly, H3.3/MOF increases the level of H4K16ac by a mutual cooperation manner. However, the H3.3K36R mutant could not increase the level of H4K16ac. RNA-seq data show the GLI1, a transcriptional regulator, is downregulated in H3.3 knockdown NSCs. Furthermore, the neurogenesis phenotype of the GLI1 knockdown is consistent with the H3.3 knockdown. Overexpression of the H3.3, MOF, and GLI1 could rescue the abnormal phenotype caused by H3.3 knockdown in the embryonic brain, but H3.1 or H3.3K36R overexpression can not rescue it. Taken together, these results suggest that H3.3 cooperates with MOF to increase the level of the H4K16ac and the GLI1, and then regulates the NSCs proliferation and differentiation.


Assuntos
Encéfalo/citologia , Encéfalo/metabolismo , Histonas/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Animais , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular , Imunoprecipitação da Cromatina , Eletroporação , Feminino , Humanos , Imunoprecipitação , Camundongos , Neurogênese/genética , Neurogênese/fisiologia , Gravidez , Processamento de Proteína Pós-Traducional , Útero/metabolismo
17.
Stem Cells ; 35(6): 1479-1492, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28276603

RESUMO

Mitochondrial metabolism is a fundamental process in tissue development. How this process play functions in embryonic neurogenesis remains largely unknown. Here, we show that mitochondrial uncoupling protein 2 (UCP2) regulates the embryonic neurogenesis by inhibiting the production of reactive oxygen species (ROS), which affect the proliferation of progenitors. In the embryonic brains of UCP2 knockdown or condition knockout mice, the proliferation of progenitors is significantly increased, while the differentiation of progenitors is reduced. Furthermore, we identify that Yap is the response protein of UCP2-mediated ROS production. When UCP2 is inactive, the production of ROS is increased. The amount of Yap protein is increased as Yap degradation through ubiquitin-proteasome proteolytic pathway is decreased. The defect caused by UCP2 depression can be rescued by Yap downregulation. Collectively, our results demonstrate that UCP2 regulates embryonic neurogenesis through ROS-mediated Yap alternation, thus shedding new sight on mitochondrial metabolism involved in embryonic neurogenesis. Stem Cells 2017;35:1479-1492.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neocórtex/embriologia , Neocórtex/metabolismo , Neurogênese , Fosfoproteínas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Desacopladora 2/metabolismo , Animais , Ciclo Celular , Proteínas de Ciclo Celular , Diferenciação Celular , Proliferação de Células , Regulação para Baixo , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Camundongos , Modelos Biológicos , Neurônios/citologia , Transporte Proteico , Frações Subcelulares/metabolismo
18.
Development ; 144(3): 441-451, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28003215

RESUMO

Sirt1 is a member of the sirtuin family of proteins and has important roles in numerous biological processes. Sirt1-/- mice display an increased frequency of abnormal spermatozoa, but the mechanism of Sirt1 in spermiogenesis remains largely unknown. Here, we report that Sirt1 might be directly involved in spermiogenesis in germ cells but not in steroidogenic cells. Germ cell-specific Sirt1 knockout mice were almost completely infertile; the early mitotic and meiotic progression of germ cells in spermatogenesis were not obviously affected after Sirt1 depletion, but subsequent spermiogenesis was disrupted by a defect in acrosome biogenesis, which resulted in a phenotype similar to that observed in human globozoospermia. In addition, LC3 and Atg7 deacetylation was disrupted in spermatids after knocking out Sirt1, which affected the redistribution of LC3 from the nucleus to the cytoplasm and the activation of autophagy. Furthermore, Sirt1 depletion resulted in the failure of LC3 to be recruited to Golgi apparatus-derived vesicles and in the failure of GOPC and PICK1 to be recruited to nucleus-associated acrosomal vesicles. Taken together, these findings reveal that Sirt1 has a novel physiological function in acrosome biogenesis.


Assuntos
Acrossomo/fisiologia , Sirtuína 1/fisiologia , Espermatogênese/fisiologia , Acrossomo/patologia , Animais , Autofagia/genética , Autofagia/fisiologia , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , Modelos Animais de Doenças , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão , Modelos Biológicos , Proteínas Nucleares/metabolismo , Fenótipo , Sirtuína 1/deficiência , Sirtuína 1/genética , Espermatogênese/genética , Espermatozoides/patologia , Espermatozoides/fisiologia , Esteroides/biossíntese , Teratozoospermia/etiologia , Teratozoospermia/patologia
19.
Cell Rep ; 17(9): 2326-2339, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27880907

RESUMO

The direct conversion of somatic cells to neurons by bypassing the multipotent cell state may be a powerful approach for personalized medicine. In addition to neuronal transcription factors and multiple small molecules, we find that epigenetic modification also contributes to the direct conversion of fibroblasts to neurons. Here, we show that Tet3, a DNA dioxygenase, can rapidly and efficiently convert fibroblasts directly into functional neurons. The induced neurons (iNs) express pan and mature neuronal markers such as Tuj1, Synapsin, and neuronal nuclei (NeuN). Gene expression profiles demonstrate distinct neuron-specific gene clusters in iNs compared with primary neurons. Induced neurons display maturing firing patterns and form functional synapses. Additionally, we observe that the level of 5hmC in iNs gradually increases during the time course of transdifferentiation. These findings suggest that DNA demethylation may regulate direct lineage commitment, representing an avenue for investigating the process of transdifferentiation.


Assuntos
Metilação de DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fibroblastos/citologia , Neurônios/citologia , Proteínas Proto-Oncogênicas/metabolismo , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animais , Biomarcadores/metabolismo , Fenômenos Eletrofisiológicos , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Neurônios/metabolismo , Oxirredução , Transcrição Genética
20.
Autophagy ; 12(11): 2000-2008, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27575019

RESUMO

Pluripotent stem cells, including induced pluripotent and embryonic stem cells (ESCs), have less developed mitochondria than somatic cells and, therefore, rely more heavily on glycolysis for energy production. 1-3 However, how mitochondrial homeostasis matches the demands of nuclear reprogramming and regulates pluripotency in ESCs is largely unknown. Here, we identified ATG3-dependent autophagy as an executor for both mitochondrial remodeling during somatic cell reprogramming and mitochondrial homeostasis regulation in ESCs. Dysfunctional autophagy by Atg3 deletion inhibited mitochondrial removal during pluripotency induction, resulting in decreased reprogramming efficiency and accumulation of abnormal mitochondria in established iPSCs. In Atg3 null mouse ESCs, accumulation of aberrant mitochondria was accompanied by enhanced ROS generation, defective ATP production and attenuated pluripotency gene expression, leading to abnormal self-renewal and differentiation. These defects were rescued by reacquisition of wild-type but not lipidation-deficient Atg3 expression. Taken together, our findings highlight a critical role of ATG3-dependent autophagy for mitochondrial homeostasis regulation in both pluripotency acquirement and maintenance.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Homeostase , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Mitocôndrias/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Animais , Diferenciação Celular , Autorrenovação Celular , Reprogramação Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Camundongos , Mitocôndrias/ultraestrutura , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo
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