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1.
Science ; 370(6513): 241-247, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32855215

RESUMO

Recent outbreaks of Ebola virus (EBOV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have exposed our limited therapeutic options for such diseases and our poor understanding of the cellular mechanisms that block viral infections. Using a transposon-mediated gene-activation screen in human cells, we identify that the major histocompatibility complex (MHC) class II transactivator (CIITA) has antiviral activity against EBOV. CIITA induces resistance by activating expression of the p41 isoform of invariant chain CD74, which inhibits viral entry by blocking cathepsin-mediated processing of the Ebola glycoprotein. We further show that CD74 p41 can block the endosomal entry pathway of coronaviruses, including SARS-CoV-2. These data therefore implicate CIITA and CD74 in host defense against a range of viruses, and they identify an additional function of these proteins beyond their canonical roles in antigen presentation.


Assuntos
Antígenos de Diferenciação de Linfócitos B/fisiologia , Betacoronavirus/fisiologia , Infecções por Coronavirus/imunologia , Ebolavirus/fisiologia , Doença pelo Vírus Ebola/imunologia , Antígenos de Histocompatibilidade Classe II/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Proteínas Nucleares/fisiologia , Pneumonia Viral/imunologia , Transativadores/fisiologia , Internalização do Vírus , Antígenos de Diferenciação de Linfócitos B/genética , Linhagem Celular Tumoral , Infecções por Coronavirus/virologia , Elementos de DNA Transponíveis , Endossomos/virologia , Testes Genéticos , Doença pelo Vírus Ebola/virologia , Antígenos de Histocompatibilidade Classe II/genética , Interações Hospedeiro-Patógeno/genética , Humanos , Proteínas Nucleares/genética , Pandemias , Pneumonia Viral/virologia , Transativadores/genética , Transcrição Genética
2.
Nat Cell Biol ; 22(8): 960-972, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32719551

RESUMO

It remains unknown if biophysical or material properties of biomolecular condensates regulate cancer. Here we show that AKAP95, a nuclear protein that regulates transcription and RNA splicing, plays an important role in tumorigenesis by supporting cancer cell growth and suppressing oncogene-induced senescence. AKAP95 forms phase-separated and liquid-like condensates in vitro and in nucleus. Mutations of key residues to different amino acids perturb AKAP95 condensation in opposite directions. Importantly, the activity of AKAP95 in splice regulation is abolished by disruption of condensation, significantly impaired by hardening of condensates, and regained by substituting its condensation-mediating region with other condensation-mediating regions from irrelevant proteins. Moreover, the abilities of AKAP95 in regulating gene expression and supporting tumorigenesis require AKAP95 to form condensates with proper liquidity and dynamicity. These results link phase separation to tumorigenesis and uncover an important role of appropriate biophysical properties of protein condensates in gene regulation and cancer.


Assuntos
Proteínas de Ancoragem à Quinase A/fisiologia , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Proteínas Nucleares/fisiologia , Processamento de RNA , Proteínas de Ancoragem à Quinase A/química , Animais , Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Senescência Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Proteínas Nucleares/química , Transição de Fase , Processamento de RNA/fisiologia , Relação Estrutura-Atividade
3.
Nucleic Acids Res ; 48(14): 7609-7622, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32476018

RESUMO

The splicing of tRNA introns is a critical step in pre-tRNA maturation. In archaea and eukaryotes, tRNA intron removal is catalyzed by the tRNA splicing endonuclease (TSEN) complex. Eukaryotic TSEN is comprised of four core subunits (TSEN54, TSEN2, TSEN34 and TSEN15). The human TSEN complex additionally co-purifies with the polynucleotide kinase CLP1; however, CLP1's role in tRNA splicing remains unclear. Mutations in genes encoding all four TSEN subunits, as well as CLP1, are known to cause neurodegenerative disorders, yet the mechanisms underlying the pathogenesis of these disorders are unknown. Here, we developed a recombinant system that produces active TSEN complex. Co-expression of all four TSEN subunits is required for efficient formation and function of the complex. We show that human CLP1 associates with the active TSEN complex, but is not required for tRNA intron cleavage in vitro. Moreover, RNAi knockdown of the Drosophila CLP1 orthologue, cbc, promotes biogenesis of mature tRNAs and circularized tRNA introns (tricRNAs) in vivo. Collectively, these and other findings suggest that CLP1/cbc plays a regulatory role in tRNA splicing by serving as a negative modulator of the direct tRNA ligation pathway in animal cells.


Assuntos
Endorribonucleases/metabolismo , Precursores de RNA/metabolismo , RNA de Transferência/metabolismo , Proteínas de Drosophila/fisiologia , Éxons , Humanos , Íntrons , Proteínas Nucleares/metabolismo , Proteínas Nucleares/fisiologia , Fosfotransferases/metabolismo , Fosfotransferases/fisiologia , Clivagem do RNA , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia
4.
Int J Nanomedicine ; 15: 2947-2955, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425526

RESUMO

Introduction: ZnO quantum dots (QDs) have drawn much attention recently as they are Cd-free, low-cost, and have excellent optical properties. With the expanded production and application of ZnO nanoparticles, concerns about their potential toxicity have also been raised. Materials and Methods: We used RNA sequencing (RNA-seq) to analyze the global gene expression of liver and lung tissues after ZnO QDs treatment. Differentially expressed genes (DEGs) were screened, with a fold change >1.5 and padj <0.05. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed, and padj <0.05 was considered significantly enriched. The RNA-seq results were validated by quantitative real-time polymerase chain reaction (qRT-PCR). Results: A total of 47 and 218 genes were significantly differentially expressed in the liver and lung. Eight GO terms were enriched in the liver and lung, and retinol metabolism and the peroxisome proliferator-activated receptor (PPAR) signaling pathway were shared in different tissues. Discussion: According to DEGs and pathway enrichment analyses, inflammation might be induced in liver and lung tissues after intravenous injection of ZnO QDs. These findings will be helpful for future research and application of ZnO QDs.


Assuntos
Fígado/efeitos dos fármacos , Proteínas de Neoplasias/efeitos dos fármacos , Proteínas Nucleares/efeitos dos fármacos , Pontos Quânticos/toxicidade , Ubiquitina-Proteína Ligases/efeitos dos fármacos , Óxido de Zinco/toxicidade , Animais , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Fígado/fisiologia , Masculino , Camundongos , Proteínas de Neoplasias/fisiologia , Proteínas Nucleares/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Testes de Toxicidade , Ubiquitina-Proteína Ligases/fisiologia
5.
PLoS Pathog ; 16(5): e1008188, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32365080

RESUMO

As a canonical adaptor for the Toll-like receptor (TLR) family, myeloid differentiation primary response protein 88 (MyD88) has crucial roles in host defense against infection by microbial pathogens, and its dysregulation might induce autoimmune diseases. Here, we demonstrate that the chicken Cullin 3-based ubiquitin ligase adaptor Speckle-type BTB-POZ protein (chSPOP) recognizes the intermediate domain of chicken MyD88 (chMyD88) and degrades it through the proteasome pathway. Knockdown or genetic ablation of chSPOP leads to aberrant elevation of chMyD88 protein. Through this interaction, chSPOP negatively regulates NF-κB pathway activity and thus the production of IL-1ß upon LPS challenge in chicken macrophages. Furthermore, Spop-deficient mice are more susceptible to infection with Salmonella typhimurium. Collectively, these findings demonstrate MyD88 as a bona fide substrate of SPOP and uncover a mechanism by which SPOP regulates MyD88 abundance and disease susceptibility.


Assuntos
Fator 88 de Diferenciação Mieloide/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Células CHO , Galinhas/metabolismo , Cricetulus , Proteínas Culina/metabolismo , Células HeLa , Humanos , Imunidade Inata/fisiologia , Camundongos , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/fisiologia , Proteínas Nucleares/fisiologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteostase/fisiologia , Proteínas Repressoras/fisiologia , Transdução de Sinais , Ubiquitina/metabolismo , Ubiquitinação
6.
PLoS Pathog ; 16(5): e1008190, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32413071

RESUMO

DNA replication protein Cdc45 is an integral part of the eukaryotic replicative helicase whose other components are the Mcm2-7 core, and GINS. We identified a PIP box motif in Leishmania donovani Cdc45. This motif is typically linked to interaction with the eukaryotic clamp proliferating cell nuclear antigen (PCNA). The homotrimeric PCNA can potentially bind upto three different proteins simultaneously via a loop region present in each monomer. Multiple binding partners have been identified from among the replication machinery in other eukaryotes, and the concerted /sequential binding of these partners are central to the fidelity of the replication process. Though conserved in Cdc45 across Leishmania species and Trypanosoma cruzi, the PIP box is absent in Trypanosoma brucei Cdc45. Here we investigate the possibility of Cdc45-PCNA interaction and the role of such an interaction in the in vivo context. Having confirmed the importance of Cdc45 in Leishmania DNA replication we establish that Cdc45 and PCNA interact stably in whole cell extracts, also interacting with each other directly in vitro. The interaction is mediated via the Cdc45 PIP box. This PIP box is essential for Leishmania survival. The importance of the Cdc45 PIP box is also examined in Schizosaccharomyces pombe, and it is found to be essential for cell survival here as well. Our results implicate a role for the Leishmania Cdc45 PIP box in recruiting or stabilizing PCNA on chromatin. The Cdc45-PCNA interaction might help tether PCNA and associated replicative DNA polymerase to the DNA template, thus facilitating replication fork elongation. Though multiple replication proteins that associate with PCNA have been identified in other eukaryotes, this is the first report demonstrating a direct interaction between Cdc45 and PCNA, and while our analysis suggests the interaction may not occur in human cells, it indicates that it may not be confined to trypanosomatids.


Assuntos
Leishmania donovani/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/fisiologia , Cromatina/genética , DNA Helicases/metabolismo , Replicação do DNA/fisiologia , Leishmania donovani/genética , Proteínas Nucleares/genética , Proteínas Nucleares/fisiologia , Nucleotidiltransferases/genética , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ligação Proteica , Domínios Proteicos , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/fisiologia , Análise de Sequência de Proteína/métodos
7.
Plant Mol Biol ; 103(1-2): 197-210, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32130643

RESUMO

DEEPER ROOTING 1 (DRO1) contributes to the downward gravitropic growth trajectory of roots upstream of lateral auxin transport in monocots and dicots. Loss of DRO1 function leads to horizontally oriented lateral roots and altered gravitropic set point angle, while loss of all three DRO family members results in upward, vertical root growth. Here, we attempt to dissect the roles of AtDRO1 by analyzing expression, protein localization, auxin gradient formation, and auxin responsiveness in the atdro1 mutant. Current evidence suggests AtDRO1 is predominantly a membrane-localized protein. Here we show that VENUS-tagged AtDRO1 driven by the native AtDRO1 promoter complemented an atdro1 Arabidopsis mutant and the protein was localized in root tips and detectable in nuclei. atdro1 primary and lateral roots showed impairment in establishing an auxin gradient upon gravistimulation as visualized with DII-VENUS, a sensor for auxin signaling and proxy for relative auxin distribution. Additionally, PIN3 domain localization was not significantly altered upon gravistimulation in atdro1 primary and lateral roots. RNA-sequencing revealed differential expression of known root development-related genes in atdro1 mutants. atdro1 lateral roots were able to respond to exogenous auxin and AtDRO1 gene expression levels in root tips were unaffected by the addition of auxin. Collectively, the data suggest that nuclear localization may be important for AtDRO1 function and suggests a more nuanced role for DRO1 in regulating auxin-mediated changes in lateral branch angle. KEY MESSAGE: DEEPER ROOTING 1 (DRO1) when expressed from its native promoter is predominately localized in Arabidopsis root tips, detectable in nuclei, and impacts auxin gradient formation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas Nucleares/fisiologia , Raízes de Plantas/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiologia , Núcleo Celular/metabolismo , Teste de Complementação Genética , Gravitação , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-32200192

RESUMO

The basic region/leucine zipper (bZIP) transcription factors play key roles in regulating diverse biological processes in plants. However, their participation in shoot branching has been rarely reported. Here, we isolated a CmbZIP1 transcription factor gene, a member of the bZIP family, from chrysanthemum. Subcellular localization analysis indicated that CmbZIP1 is a nuclear protein. Tissue-specific expression analysis indicated that CmbZIP1 was principally expressed in apical bud and axillary bud. Expression patterns analysis results showed that CmbZIP1 expression was suppressed in axillary buds in response to decapitation but increased in response to shade. Overexpression of CmbZIP1 in Arabidopsis inhibits its shoot branching. In addition, expression of auxin efflux protein PIN-FORMED 1 (PIN1) and auxin signaling components AUXIN RESISTANT 1/3 (AXR1, AXR3) were significantly up-regulated in overexpressing plants in comparison with wild type plants. Moreover, the transcript expression of BRANCHED 2 (AtBRC2) was also significantly up-regulated in overexpressing plants compared with the wild type. Altogether, these results suggest important and negative roles of CmbZIP1 in shoot branching. Our study extends the understanding of the function of bZIP transcription factors in plants and provides valuable gene resources for improving the architectural traits of ornamental plants.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Chrysanthemum/crescimento & desenvolvimento , Proteínas de Plantas/fisiologia , Brotos de Planta/crescimento & desenvolvimento , Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas Nucleares/fisiologia , Plantas Geneticamente Modificadas
9.
Leukemia ; 34(8): 2051-2063, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32076119

RESUMO

Blast crisis of chronic myeloid leukemia is associated with poor survival and the accumulation of genomic lesions. Using whole-exome and/or RNA sequencing of patients at chronic phase (CP, n = 49), myeloid blast crisis (MBC, n = 19), and lymphoid blast crisis (LBC, n = 20), we found 25 focal gene deletions and 14 fusions in 24 patients in BC. Deletions predominated in LBC (83% of structural variants). Transcriptional analysis identified the upregulation of genes involved in V(D)J recombination, including RAG1/2 and DNTT in LBC. RAG recombination is a reported mediator of IKZF1 deletion. We investigated the extent of RAG-mediated genomic lesions in BC. Molecular hallmarks of RAG activity; DNTT-mediated nucleotide insertions and a RAG-binding motif at structural variants were exclusively found in patients with high RAG expression. Structural variants in 65% of patients in LBC displayed these hallmarks compared with only 5% in MBC. RAG-mediated events included focal deletion and novel fusion of genes associated with hematologic cancer: IKZF1, RUNX1, CDKN2A/B, and RB1. Importantly, 8/8 patients with elevated DNTT at CP diagnosis progressed to LBC by 12 months, potentially enabling early prediction of LBC. This work confirms the central mutagenic role of RAG in LBC and describes potential clinical utility in CML management.


Assuntos
Crise Blástica/genética , Proteínas de Ligação a DNA/fisiologia , Proteínas de Homeodomínio/fisiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas Nucleares/fisiologia , Recombinação Genética , Biologia Computacional , DNA Nucleotidilexotransferase/genética , Proteínas de Ligação a DNA/genética , Deleção de Genes , Proteínas de Homeodomínio/genética , Humanos , Proteínas Nucleares/genética
10.
Development ; 147(6)2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32094113

RESUMO

Noradrenaline belongs to the monoamine system and is involved in cognition and emotional behaviors. Phox2a and Phox2b play essential but non-redundant roles during development of the locus coeruleus (LC), the main noradrenergic (NA) neuron center in the mammalian brain. The ubiquitin E3 ligase Rnf220 and its cofactor Zc4h2 participate in ventral neural tube patterning by modulating Shh/Gli signaling, and ZC4H2 mutation is associated with intellectual disability, although the mechanisms for this remain poorly understood. Here, we report that Zc4h2 and Rnf220 are required for the development of central NA neurons in the mouse brain. Both Zc4h2 and Rnf220 are expressed in developing LC-NA neurons. Although properly initiated at E10.5, the expression of genes associated with LC-NA neurons is not maintained at the later embryonic stages in mice with a deficiency of either Rnf220 or Zc4h2 In addition, we show that the Rnf220/Zc4h2 complex monoubiquitylates Phox2a/Phox2b, a process required for the full transcriptional activity of Phox2a/Phox2b. Our work reveals a role for Rnf220/Zc4h2 in regulating LC-NA neuron development, and this finding may be helpful for understanding the pathogenesis of ZC4H2 mutation-associated intellectual disability.


Assuntos
Neurônios Adrenérgicos/fisiologia , Proteínas de Homeodomínio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Neurogênese/fisiologia , Proteínas Nucleares/fisiologia , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Ubiquitinação/genética , Neurônios Adrenérgicos/metabolismo , Animais , Diferenciação Celular/genética , Embrião de Galinha , Embrião de Mamíferos , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Norepinefrina/metabolismo
11.
Bull Cancer ; 107(1): 41-47, 2020 Jan.
Artigo em Francês | MEDLINE | ID: mdl-31916995

RESUMO

A growing number of studies suggest a tumor suppressor role for the SWI/SNF complex involved in the remodeling of chromatin. Alterations of this complex have been found in many tumors of different origins, with topographic, morphologic and phenotypic diversity. Notably, they define 2 types of thoracic tumors: SMARCA4-deficient non-small cell lung carcinoma and SMARCA4-deficient sarcoma. Some clinical features appear to be common to both, such as intrathoracic localization, smoking exposure, male predominance and poor prognosis. However, the histological distinction between these two entities is sometimes difficult and it is not excluded that these entities belong to the same tumor spectrum with different degrees of differentiation. The therapy of these tumors is not yet codified. These tumors do not seem associated with oncogenic driver mutations allowing the prescription of targeted therapy, but immunotherapy has been shown to be effective in rare reported cases. More specific treatments using EZH2 inhibitors also seem promising in SMARCA4 deficient sarcomas.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Montagem e Desmontagem da Cromatina , DNA Helicases/deficiência , Proteínas de Neoplasias/deficiência , Proteínas Nucleares/deficiência , Sarcoma/genética , Neoplasias Torácicas/genética , Fatores de Transcrição/deficiência , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Quimiorradioterapia , Montagem e Desmontagem da Cromatina/genética , Montagem e Desmontagem da Cromatina/fisiologia , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução , DNA Helicases/fisiologia , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Neoplasias do Mediastino/genética , Neoplasias do Mediastino/patologia , Neoplasias do Mediastino/terapia , Terapia de Alvo Molecular , Complexos Multiproteicos/efeitos dos fármacos , Complexos Multiproteicos/fisiologia , Invasividade Neoplásica , Proteínas de Neoplasias/fisiologia , Proteínas Nucleares/fisiologia , Proteína SMARCB1/fisiologia , Sarcoma/patologia , Sarcoma/terapia , Neoplasias Torácicas/patologia , Neoplasias Torácicas/terapia , Fatores de Transcrição/fisiologia
13.
Life Sci ; 242: 117159, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31837334

RESUMO

AIMS: It has been shown that up-regulation of E3 ubiquitin ligase seven-in-absentia-homolog 2 (Siah2) and activation of Hippo signaling pathway effector yes-associated protein (YAP) are involved in the development of pulmonary arterial hypertension (PAH). However, it is still unclear whether Siah2 activates YAP in monocrotaline (MCT)-induced PAH rat models. MAIN METHODS: Intraperitoneal injection of MCT was used to induce PAH rat models. The right ventricular systolic pressure (RVSP), right ventricle hypertrophy index (RVHI), percentage of medial wall thickness (%MT), α-SMA, Ki-67 and TUNEL staining were performed to evaluate the development of PAH. Protein levels of Siah2, Lats1/2, YAP phosphorylation and total YAP, and the subcellular localization of YAP were examined using immunoblotting. Proteasome activity was measured by an assay kit. KEY FINDINGS: The protein level of Siah2 was significantly increased in MCT-induced PAH rats, this was accompanied with the proteasome-dependent degradation of Lats1/2 and subsequent up-regulation and dephosphorylation of YAP and its nuclear localization. Administration of PAH rats with Siah2 inhibitor Vitamin K3 or proteasome inhibitor MG-132 dramatically suppressed MCT-induced down-regulation of Lats1/2 and activation of YAP, finally reduced RVSP, RVHI, %MT, pulmonary arterial muscularization, pulmonary arterial smooth muscle cells (PASMCs) proliferation and enhanced PASMCs apoptosis in PAH rats. SIGNIFICANCE: Siah2 contributes to the development of MCT-induced PAH by destabilizing Lats1/2 and subsequently stimulating YAP activation. Inhibition of Siah2 or proteasome alleviates pulmonary arterial remodeling through inactivation of YAP, indicating Siah2 ubiquitin ligase as a novel target might have potential value in the management of PAH.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Monocrotalina/farmacologia , Proteínas Nucleares/fisiologia , Hipertensão Arterial Pulmonar/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Remodelação Vascular/efeitos dos fármacos , Animais , Proteínas Reguladoras de Apoptose/fisiologia , Immunoblotting , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiologia , Hipertensão Arterial Pulmonar/induzido quimicamente , Hipertensão Arterial Pulmonar/fisiopatologia , Ratos , Ratos Sprague-Dawley , Remodelação Vascular/fisiologia
14.
Development ; 147(1)2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31857347

RESUMO

Embryonic interneuron development underlies cortical function and its disruption contributes to neurological disease. Yet the mechanisms by which viable interneurons are produced from progenitors remain poorly understood. Here, we demonstrate dosage-dependent requirements of the exon junction complex component Magoh for interneuron genesis in mouse. Conditional Magoh ablation from interneuron progenitors, but not post-mitotic neurons, depletes cortical interneuron number through adulthood, with increased severity in homozygotes. Using live imaging, we discover that Magoh deficiency delays progenitor mitotic progression in a dosage-sensitive fashion, with 40% of homozygous progenitors failing to divide. This shows that Magoh is required in progenitors for both generation and survival of newborn progeny. Transcriptome analysis implicates p53 signaling; moreover, p53 ablation in Magoh haploinsufficient progenitors rescues apoptosis, completely recovering interneuron number. In striking contrast, in Magoh homozygotes, p53 loss fails to rescue interneuron number and mitotic delay, further implicating mitotic defects in interneuron loss. Our results demonstrate that interneuron development is intimately dependent upon progenitor mitosis duration and uncover a crucial post-transcriptional regulator of interneuron fate relevant for neurodevelopmental pathologies.This article has an associated 'The people behind the papers' interview.


Assuntos
Córtex Cerebral/citologia , Interneurônios/fisiologia , Neurogênese/fisiologia , Proteínas Nucleares/fisiologia , Animais , Proliferação de Células , Sobrevivência Celular , Córtex Cerebral/embriologia , Perfilação da Expressão Gênica , Processamento de Imagem Assistida por Computador , Camundongos , Mitose/fisiologia , Células-Tronco Neurais/fisiologia , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
15.
BMC Plant Biol ; 19(1): 586, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881835

RESUMO

BACKGROUND: In soft fruits, the differential expression of many genes during development and ripening is responsible for changing their organoleptic properties. In strawberry fruit, although some genes involved in the metabolic regulation of the ripening process have been functionally characterized, some of the most studied genes correspond to transcription factors. High throughput transcriptomics analyses performed in strawberry red receptacle (Fragaria x ananassa) allowed us to identify a ripening-related gene that codes an atypical HLH (FaPRE1) with high sequence homology with the PACLOBUTRAZOL RESISTANCE (PRE) genes. PRE genes are atypical bHLH proteins characterized by the lack of a DNA-binding domain and whose function has been linked to the regulation of cell elongation processes. RESULTS: FaPRE1 sequence analysis indicates that this gene belongs to the subfamily of atypical bHLHs that also includes ILI-1 from rice, SlPRE2 from tomato and AtPRE1 from Arabidopsis, which are involved in transcriptional regulatory processes as repressors, through the blockage by heterodimerization of bHLH transcription factors. FaPRE1 presented a transcriptional model characteristic of a ripening-related gene with receptacle-specific expression, being repressed by auxins and activated by abscisic acid (ABA). However, its expression was not affected by gibberellic acid (GA3). On the other hand, the transitory silencing of FaPRE1 transcription by agroinfiltration in receptacle produced the down-regulation of a group of genes related to the ripening process while inducing the transcription of genes involved in receptacle growth and development. CONCLUSIONS: In summary, this work presents for the first time experimental data that support an important novel function for the atypical HLH FaPRE1 during the strawberry fruit ripening. We hypothesize that FaPRE1 modulates antagonistically the transcription of genes related to both receptacle growth and ripening. Thus, FaPRE1 would repress the expression of receptacle growth promoting genes in the ripened receptacle, while it would activate the expression of those genes related to the receptacle ripening process.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Fragaria/fisiologia , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fragaria/efeitos dos fármacos , Fragaria/genética , Fragaria/crescimento & desenvolvimento , Frutas/genética , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Proteínas Nucleares/genética , Proteínas Nucleares/fisiologia , Desenvolvimento Vegetal/genética , Reguladores de Crescimento de Planta/fisiologia , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Triazóis/farmacologia
17.
Front Immunol ; 10: 2797, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31867002

RESUMO

Sestrin2 (SESN2), a highly evolutionarily conserved protein, is critically involved in cellular responses to various stresses. SESN2 has a protective effect on physiological and pathological states mainly via regulating oxidative stress, endoplasmic reticulum stress, autophagy, metabolism, and inflammation. In recent years, breakthrough investigations with regard to the regulation and signaling mechanisms of SESN2 have markedly deepened our understanding of its potential role as well as its significance in host response. However, the functions of SESN2 in the immune system and inflammation remain elusive. It has been documented that many immune cells positively express SESN2 and, in turn, that SESN2 might modulate cellular activities. This review incorporates recent progress and aims to provide novel insight into the protective role and regulatory pathway of SESN2, which acts as a potential biomarker and therapeutic target in the context of various diseases.


Assuntos
Imunidade , Proteínas Nucleares/fisiologia , Autofagia , Dano ao DNA , Estresse do Retículo Endoplasmático , Humanos , Hipóxia/metabolismo , Inflamassomos/fisiologia , Hepatopatias/imunologia , Macrófagos/imunologia , Estresse Oxidativo , Sepse/imunologia
18.
Nat Commun ; 10(1): 4647, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604927

RESUMO

Human embryonic stem cell-derived beta cells offer a promising cell-based therapy for diabetes. However, efficient stem cell to beta cell differentiation has proven difficult, possibly due to the lack of cross-talk with the appropriate mesenchymal niche. To define organ-specific niche signals, we isolated pancreatic and gastrointestinal stromal cells, and analyzed their gene expression during development. Our genetic studies reveal the importance of tightly regulated Hedgehog signaling in the pancreatic mesenchyme: inactivation of mesenchymal signaling leads to annular pancreas, whereas stroma-specific activation of signaling via loss of Hedgehog regulators, Sufu and Spop, impairs pancreatic growth and beta cell genesis. Genetic rescue and transcriptome analyses show that these Sufu and Spop knockout defects occur through Gli2-mediated activation of gastrointestinal stromal signals such as Wnt ligands. Importantly, inhibition of Wnt signaling in organoid and human stem cell cultures significantly promotes insulin-producing cell generation, altogether revealing the requirement for organ-specific regulation of stromal niche signals.


Assuntos
Células-Tronco Embrionárias/citologia , Proteínas Hedgehog/metabolismo , Células Secretoras de Insulina/citologia , Proteínas Nucleares/fisiologia , Proteínas Repressoras/fisiologia , Técnicas de Cultura de Células , Diferenciação Celular , Terapia Baseada em Transplante de Células e Tecidos/métodos , Diabetes Mellitus/terapia , Regulação para Baixo , Humanos , Células Secretoras de Insulina/transplante , Proteínas Nucleares/metabolismo , Organoides/citologia , Proteínas Repressoras/metabolismo , Proteínas Wnt/metabolismo
19.
G3 (Bethesda) ; 9(11): 3583-3593, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31484673

RESUMO

Protein phosphatase V (PpV) encodes the Drosophila homolog of the evolutionarily conserved Protein Phosphatase 6 (PP6). The physiological and developmental functions of PpV/PP6 have not been well characterized due to lack of a genetically defined mutant. Here, we identified a PpV non-sense mutation and describe multiple mutant phenotypes in oogenesis and early embryogenesis. Specifically, we found that the defects in chromosome segregation during nuclear cycles are related to AuroraA function, which is consistent with the interaction of PP6 and AuroraA in mammalian cells. Surprisingly, we also identified a PpV function specifically in blastoderm cell cycle but not in cell proliferation in the follicle epithelium or larval wing imaginal discs. Embryos from PpV germline clones frequently undergo an extra nuclear division cycle. By epistasis analysis, we found that PpV functions in parallel with tribbles, but independently of auroraA for the remodeling of the nuclear cycles. Taken together, this study reports novel developmental functions of PpV and provides a framework for further genetic analysis under physiological conditions.


Assuntos
Proteínas de Drosophila/genética , Drosophila/genética , Desenvolvimento Embrionário/genética , Genes Essenciais , Genes de Insetos , Proteínas Nucleares/genética , Fosfoproteínas Fosfatases/genética , Animais , Aurora Quinase A/genética , Proteínas de Ciclo Celular/genética , Drosophila/crescimento & desenvolvimento , Proteínas de Drosophila/fisiologia , Embrião não Mamífero , Feminino , Mutação , Proteínas Nucleares/fisiologia , Oogênese/genética , Fosfoproteínas Fosfatases/fisiologia , Proteínas Serina-Treonina Quinases/genética
20.
Brain Behav Evol ; 93(2-3): 152-165, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31416089

RESUMO

The coordination of progenitor self-renewal, neuronal production, and migration is essential to the normal development and evolution of the cerebral cortex. Numerous studies have shown that the Notch, Wnt/beta-catenin, and Neurogenin pathways contribute separately to progenitor expansion, neurogenesis, and neuronal migration, but it is unknown how these signals are coordinated. In vitro studies suggested that the mastermind-like 1 (MAML1) gene, homologue of the Drosophila mastermind, plays a role in coordinating the aforementioned signaling pathways, yet its role during cortical development remains largely unknown. Here we show that ectopic expression of dominant-negative MAML (dnMAML) causes exuberant neuronal production in the mouse cortex without disrupting neuronal migration. Comparing the transcriptional consequences of dnMAML and Neurog2 ectopic expression revealed a complex genetic network controlling the balance of progenitor expansion versus neuronal production. Manipulation of MAML and Neurog2 in cultured human cerebral stem cells exposed interactions with the same set of signaling pathways. Thus, our data suggest that evolutionary changes that affect the timing, tempo, and density of successive neuronal layers of the small lissencephalic rodent and large convoluted primate cerebral cortex depend on similar molecular mechanisms that act from the earliest developmental stages.


Assuntos
Córtex Cerebral/fisiologia , Proteínas de Ligação a DNA/fisiologia , Redes Reguladoras de Genes/fisiologia , Neurogênese/fisiologia , Proteínas Nucleares/fisiologia , Transdução de Sinais/fisiologia , Fatores de Transcrição/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Córtex Cerebral/crescimento & desenvolvimento , Proteínas de Ligação a DNA/genética , Embrião de Mamíferos , Feminino , Feto , Regulação da Expressão Gênica , Redes Reguladoras de Genes/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/fisiologia , Células-Tronco Neurais , Proteínas Nucleares/genética , Gravidez , Transdução de Sinais/genética , Fatores de Transcrição/genética
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