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1.
Science ; 367(6479): 763-768, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32054757

RESUMO

Effector-triggered immunity (ETI), induced by host immune receptors in response to microbial effectors, protects plants against virulent pathogens. However, a systematic study of ETI prevalence against species-wide pathogen diversity is lacking. We constructed the Pseudomonas syringae Type III Effector Compendium (PsyTEC) to reduce the pan-genome complexity of 5127 unique effector proteins, distributed among 70 families from 494 strains, to 529 representative alleles. We screened PsyTEC on the model plant Arabidopsis thaliana and identified 59 ETI-eliciting alleles (11.2%) from 19 families (27.1%), with orthologs distributed among 96.8% of P. syringae strains. We also identified two previously undescribed host immune receptors, including CAR1, which recognizes the conserved effectors AvrE and HopAA1, and found that 94.7% of strains harbor alleles predicted to be recognized by either CAR1 or ZAR1.


Assuntos
Arabidopsis/imunologia , Arabidopsis/microbiologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Pseudomonas syringae/patogenicidade , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , Genoma de Planta , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/genética , Pseudomonas syringae/genética
2.
Science ; 367(6476): 436-440, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31974253

RESUMO

The ability of the nervous system to sense cellular stress and coordinate protein homeostasis is essential for organismal health. Unfortunately, stress responses that mitigate disturbances in proteostasis, such as the unfolded protein response of the endoplasmic reticulum (UPRER), become defunct with age. In this work, we expressed the constitutively active UPRER transcription factor, XBP-1s, in a subset of astrocyte-like glia, which extended the life span in Caenorhabditis elegans Glial XBP-1s initiated a robust cell nonautonomous activation of the UPRER in distal cells and rendered animals more resistant to protein aggregation and chronic ER stress. Mutants deficient in neuropeptide processing and secretion suppressed glial cell nonautonomous induction of the UPRER and life-span extension. Thus, astrocyte-like glial cells play a role in regulating organismal ER stress resistance and longevity.


Assuntos
Caenorhabditis elegans/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Longevidade , Neuroglia/fisiologia , Neuropeptídeos/fisiologia , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/fisiologia , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , Mutação , Agregados Proteicos/fisiologia , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia
3.
Adv Exp Med Biol ; 1190: 23-31, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31760635

RESUMO

Regulation of differentiation and proliferation of Schwann cells is an essential part of the regulation of peripheral nerve development, degeneration, and regeneration. ZNRF1, a ubiquitin ligase, is expressed in undifferentiated/repair Schwann cells, directs glutamine synthetase to proteasomal degradation, and thereby increase glutamate levels in Schwann cell environment. Glutamate elicits subcellular signaling in Schwann cells via mGluR2 to modulate Neuregulin-1/ErbB2/3 signaling and thereby promote undifferentiated phenotype of Schwann cell.


Assuntos
Ácido Glutâmico/fisiologia , Bainha de Mielina/fisiologia , Nervos Periféricos/fisiologia , Transdução de Sinais , Proteínas de Transporte/fisiologia , Diferenciação Celular , Humanos , Receptores de AMPA/fisiologia , Células de Schwann
4.
Insect Biochem Mol Biol ; 115: 103244, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31560967

RESUMO

Three different pheromone binding proteins (PBPs) can typically be found in the sensilla lymph of noctuid moth antennae, but their relative contributions in perception of the sex pheromone is rarely verified in vivo. Previously, we demonstrated that SlitPBP3 plays a minor role in the sex pheromone detection in Spodoptera litura using the CRISPR/Cas9 system. In the present study, the roles of two other SlitPBPs (SlitPBP1 and SlitPBP2) are further verified using the same system. First, by co-injection of Cas9 mRNA/sgRNA into newly laid eggs, a high rate of target mutagenesis was induced, 51.5% for SlitPBP1 and 46.8% for SlitPBP2 as determined by restriction enzyme assay. Then, the homozygous SlitPBP1 and SlitPBP2 knockout lines were obtained by cross-breeding. Finally, using homozygous knockout male moths, we performed electrophysiological (EAG recording) and behavioral analyses. Results showed that knockout of either SlitPBP1 or SlitPBP2 in males decreased EAG response to each of the 3 sex pheromone components (Z9,E11-14:Ac, Z9,E12-14:Ac and Z9-14:Ac) by 53%, 60% and 63% (for SlitPBP1 knockout) and 40%, 43% and 46% (for SlitPBP2 knockout), respectively. These decreases in EAG responses were similar among 3 pheromone components, but were more pronounced in SlitPBP1 knockout males than in SlitPBP2 knockout males. Consistently, behavioral assays with the major component (Z9,E11-14:Ac) showed that SlitPBP1 knockout males responded in much lower percentages than SlitPBP2 knockout males in terms of orientation to the pheromone, along with reduction in close range behaviors such as hairpencil display and mating attempt. Taken together, this study provides direct functional evidence for the roles of SlitPBP1 and SlitPBP2, as well as their relative importance (SlitPBP1 > SlitPBP2) in the sex pheromone perception. This information is valuable in understanding mechanisms of sex pheromone perception and may facilitate the development of PBP-targeted pest control techniques.


Assuntos
Comunicação Animal , Antenas de Artrópodes/fisiologia , Proteínas de Transporte/fisiologia , Proteínas de Insetos/fisiologia , Percepção Olfatória , Spodoptera/fisiologia , Animais , Sequência de Bases , Sistemas CRISPR-Cas , Feminino , Masculino , Mutação , Atrativos Sexuais
5.
PLoS Pathog ; 15(7): e1007987, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31356624

RESUMO

Streptococcus pneumoniae (pneumococci) is a leading cause of severe bacterial meningitis in many countries worldwide. To characterize the repertoire of fitness and virulence factors predominantly expressed during meningitis we performed niche-specific analysis of the in vivo proteome in a mouse meningitis model, in which bacteria are directly inoculated into the cerebrospinal fluid (CSF) cisterna magna. We generated a comprehensive mass spectrometry (MS) spectra library enabling bacterial proteome analysis even in the presence of eukaryotic proteins. We recovered 200,000 pneumococci from CSF obtained from meningitis mice and by MS we identified 685 pneumococci proteins in samples from in vitro filter controls and 249 in CSF isolates. Strikingly, the regulatory two-component system ComDE and substrate-binding protein AliB of the oligopeptide transporter system were exclusively detected in pneumococci recovered from the CSF. In the mouse meningitis model, AliB-, ComDE-, or AliB-ComDE-deficiency resulted in attenuated meningeal inflammation and disease severity when compared to wild-type pneumococci indicating the crucial role of ComDE and AliB in pneumococcal meningitis. In conclusion, we show here mechanisms of pneumococcal adaptation to a defined host compartment by a proteome-based approach. Further, this study provides the basis of a promising strategy for the identification of protein antigens critical for invasive disease caused by pneumococci and other meningeal pathogens.


Assuntos
Proteínas de Bactérias/fisiologia , Proteínas de Transporte/fisiologia , Lipoproteínas/fisiologia , Meningite Pneumocócica/microbiologia , Streptococcus pneumoniae/fisiologia , Streptococcus pneumoniae/patogenicidade , Fatores de Virulência/fisiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Genes Bacterianos , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Lipoproteínas/deficiência , Lipoproteínas/genética , Masculino , Meningite Pneumocócica/líquido cefalorraquidiano , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Proteômica , Regulon , Streptococcus pneumoniae/genética , Virulência/genética , Virulência/fisiologia , Fatores de Virulência/genética
6.
Nat Commun ; 10(1): 2635, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201302

RESUMO

Multidrug efflux pumps actively expel a wide range of toxic substrates from the cell and play a major role in intrinsic and acquired drug resistance. In Gram-negative bacteria, these pumps form tripartite assemblies that span the cell envelope. However, the in situ structure and assembly mechanism of multidrug efflux pumps remain unknown. Here we report the in situ structure of the Escherichia coli AcrAB-TolC multidrug efflux pump obtained by electron cryo-tomography and subtomogram averaging. The fully assembled efflux pump is observed in a closed state under conditions of antibiotic challenge and in an open state in the presence of AcrB inhibitor. We also observe intermediate AcrAB complexes without TolC and discover that AcrA contacts the peptidoglycan layer of the periplasm. Our data point to a sequential assembly process in living bacteria, beginning with formation of the AcrAB subcomplex and suggest domains to target with efflux pump inhibitors.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Transporte/fisiologia , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/fisiologia , Escherichia coli/fisiologia , Lipoproteínas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Antibacterianos/farmacologia , Proteínas de Transporte/efeitos dos fármacos , Proteínas de Transporte/ultraestrutura , Microscopia Crioeletrônica/métodos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Tomografia com Microscopia Eletrônica/métodos , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Proteínas de Escherichia coli/antagonistas & inibidores , Proteínas de Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/ultraestrutura , Microscopia Intravital/métodos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Peptidoglicano/metabolismo , Periplasma/metabolismo , Ligação Proteica/efeitos dos fármacos , Estrutura Quaternária de Proteína/efeitos dos fármacos
7.
PLoS Biol ; 17(6): e3000276, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31170139

RESUMO

The ability of neural stem cells (NSCs) to transit between quiescence and proliferation is crucial for brain development and homeostasis. Drosophila Hippo pathway maintains NSC quiescence, but its regulation during brain development remains unknown. Here, we show that CRL4Mahj, an evolutionarily conserved E3 ubiquitin ligase, is essential for NSC reactivation (exit from quiescence). We demonstrate that damaged DNA-binding protein 1 (DDB1) and Cullin4, two core components of Cullin4-RING ligase (CRL4), are intrinsically required for NSC reactivation. We have identified a substrate receptor of CRL4, Mahjong (Mahj), which is necessary and sufficient for NSC reactivation. Moreover, we show that CRL4Mahj forms a protein complex with Warts (Wts/large tumor suppressor [Lats]), a kinase of the Hippo signaling pathway, and Mahj promotes the ubiquitination of Wts. Our genetic analyses further support the conclusion that CRL4Mahj triggers NSC reactivation by inhibition of Wts. Given that Cullin4B mutations cause mental retardation and cerebral malformation, similar regulatory mechanisms may be applied to the human brain.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Drosophila/metabolismo , Células-Tronco Neurais/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Animais Geneticamente Modificados/metabolismo , Proteínas de Transporte/fisiologia , Proteínas Culina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/metabolismo , Humanos , Ligação Proteica/fisiologia , Transdução de Sinais/fisiologia , Complexos Ubiquitina-Proteína Ligase/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Ubiquitinação
8.
Nat Neurosci ; 22(7): 1089-1098, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31235908

RESUMO

Pericytes are positioned between brain capillary endothelial cells, astrocytes and neurons. They degenerate in multiple neurological disorders. However, their role in the pathogenesis of these disorders remains debatable. Here we generate an inducible pericyte-specific Cre line and cross pericyte-specific Cre mice with iDTR mice carrying Cre-dependent human diphtheria toxin receptor. After pericyte ablation with diphtheria toxin, mice showed acute blood-brain barrier breakdown, severe loss of blood flow, and a rapid neuron loss that was associated with loss of pericyte-derived pleiotrophin (PTN), a neurotrophic growth factor. Intracerebroventricular PTN infusions prevented neuron loss in pericyte-ablated mice despite persistent circulatory changes. Silencing of pericyte-derived Ptn rendered neurons vulnerable to ischemic and excitotoxic injury. Our data demonstrate a rapid neurodegeneration cascade that links pericyte loss to acute circulatory collapse and loss of PTN neurotrophic support. These findings may have implications for the pathogenesis and treatment of neurological disorders that are associated with pericyte loss and/or neurovascular dysfunction.


Assuntos
Proteínas de Transporte/fisiologia , Citocinas/fisiologia , Degeneração Neural/fisiopatologia , Proteínas do Tecido Nervoso/fisiologia , Neurônios/patologia , Pericitos/fisiologia , Choque/fisiopatologia , Animais , Isquemia Encefálica/fisiopatologia , Capilares/fisiopatologia , Proteínas de Transporte/uso terapêutico , Células Cultivadas , Circulação Cerebrovascular/fisiologia , Citocinas/deficiência , Citocinas/uso terapêutico , Células Endoteliais/citologia , Feminino , Genes Reporter , Infusões Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Degeneração Neural/tratamento farmacológico , Neuroglia/metabolismo , Neurônios/metabolismo , Neurotoxinas/toxicidade , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão/metabolismo , Choque/metabolismo , Choque/patologia
9.
Neuron ; 103(1): 52-65.e6, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31101394

RESUMO

Mitochondria are essential in long axons to provide metabolic support and sustain neuron integrity. A healthy mitochondrial pool is maintained by biogenesis, transport, mitophagy, fission, and fusion, but how these events are regulated in axons is not well defined. Here, we show that the Drosophila glutathione S-transferase (GST) Gfzf prevents mitochondrial hyperfusion in axons. Gfzf loss altered redox balance between glutathione (GSH) and oxidized glutathione (GSSG) and initiated mitochondrial fusion through the coordinated action of Mfn and Opa1. Gfzf functioned epistatically with the thioredoxin peroxidase Jafrac1 and the thioredoxin reductase 1 TrxR-1 to regulate mitochondrial dynamics. Altering GSH:GSSG ratios in mouse primary neurons in vitro also induced hyperfusion. Mitochondrial changes caused deficits in trafficking, the metabolome, and neuronal physiology. Changes in GSH and oxidative state are associated with neurodegenerative diseases like Alzheimer's. Our demonstration that GSTs are key in vivo regulators of axonal mitochondrial length and number provides a potential mechanistic link.


Assuntos
Axônios/fisiologia , Proteínas de Transporte/fisiologia , Glutationa/metabolismo , Mitocôndrias/fisiologia , Animais , Axônios/ultraestrutura , Drosophila , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Feminino , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Oxirredução , Peroxidases/genética , Peroxidases/fisiologia , Gravidez , Cultura Primária de Células , Tiorredoxina Redutase 1/genética , Tiorredoxina Redutase 1/fisiologia
10.
Plant Sci ; 284: 91-98, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084884

RESUMO

Seeds germination or dormancy is strictly controlled by endogenous phytohormone signal and environment cues. High temperature (HT) suppresses seeds germination or triggers seeds dormancy but underlying mechanism by which HT mediates seeds germination thermoinhibition needs more investigating. SOM is reported as the critical factor negatively controls light-irradiation seeds germination by altering Abscisic acid (ABA) and gibberellin acid (GA) biosynthesis. Here we found that HT accelerates SOM expressing through ABA signal transduction component ABI3, both of abi3 and som mutants seeds show high germination rate under HT in contrast to wild type seeds. Using ABI3 as the bait, we identified the epigenetic factor Powerdress (PWR) as the ABI3 interaction protein. Genetic and physiological analysis showed that PWR negatively control the expressing of SOM, and overexpressing PWR enhanced, while pwr mutant reduced, seeds germination thermotolerance. Without HT stress, PWR accelerated the histone H3 deacetylation level and H2A.Z deposition at SOM locus, and thus suppressed ABI3-dependent SOM transcription for seeds germination, HT stress block PWR transcriptional level, thus attenuated the inhibition effect of PWR on SOM expressing, resulting into seeds germination thermoinhibition. Thus our finding propose a new function of PWR in controlling seeds germination under HT through histone acetylation modification and H2A.Z deposition.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Transporte/metabolismo , Germinação , Sementes/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Proteínas de Transporte/fisiologia , Germinação/fisiologia , Resposta ao Choque Térmico , Código das Histonas , Plantas Geneticamente Modificadas , Sementes/metabolismo , Fatores de Transcrição/fisiologia , Técnicas do Sistema de Duplo-Híbrido
11.
Science ; 364(6442): 778-782, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-31123134

RESUMO

Drug-resistance dissemination by horizontal gene transfer remains poorly understood at the cellular scale. Using live-cell microscopy, we reveal the dynamics of resistance acquisition by transfer of the Escherichia coli fertility factor-conjugation plasmid encoding the tetracycline-efflux pump TetA. The entry of the single-stranded DNA plasmid into the recipient cell is rapidly followed by complementary-strand synthesis, plasmid-gene expression, and production of TetA. In the presence of translation-inhibiting antibiotics, resistance acquisition depends on the AcrAB-TolC multidrug efflux pump, because it reduces tetracycline concentrations in the cell. Protein synthesis can thus persist and TetA expression can be initiated immediately after plasmid acquisition. AcrAB-TolC efflux activity can also preserve resistance acquisition by plasmid transfer in the presence of antibiotics with other modes of action.


Assuntos
Proteínas de Transporte/fisiologia , Farmacorresistência Bacteriana Múltipla/genética , Proteínas de Escherichia coli/fisiologia , Escherichia coli/fisiologia , Fator F/fisiologia , Antibacterianos/farmacologia , Antiporters/antagonistas & inibidores , Antiporters/biossíntese , Antiporters/genética , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Conjugação Genética , DNA de Cadeia Simples , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Fator F/genética , Microscopia , Biossíntese de Proteínas/efeitos dos fármacos , Tetraciclina/farmacologia
12.
Nucleic Acids Res ; 47(13): 6826-6841, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31114918

RESUMO

Proliferating cell nuclear antigen (PCNA) is a sliding clamp that acts as a central co-ordinator for mismatch repair (MMR) as well as DNA replication. Loss of Elg1, the major subunit of the PCNA unloader complex, causes over-accumulation of PCNA on DNA and also increases mutation rate, but it has been unclear if the two effects are linked. Here we show that timely removal of PCNA from DNA by the Elg1 complex is important to prevent mutations. Although premature unloading of PCNA generally increases mutation rate, the mutator phenotype of elg1Δ is attenuated by PCNA mutants PCNA-R14E and PCNA-D150E that spontaneously fall off DNA. In contrast, the elg1Δ mutator phenotype is exacerbated by PCNA mutants that accumulate on DNA due to enhanced electrostatic PCNA-DNA interactions. Epistasis analysis suggests that PCNA over-accumulation on DNA interferes with both MMR and MMR-independent process(es). In elg1Δ, over-retained PCNA hyper-recruits the Msh2-Msh6 mismatch recognition complex through its PCNA-interacting peptide motif, causing accumulation of MMR intermediates. Our results suggest that PCNA retention controlled by the Elg1 complex is critical for efficient MMR: PCNA needs to be on DNA long enough to enable MMR, but if it is retained too long it interferes with downstream repair steps.


Assuntos
Proteínas de Transporte/fisiologia , Reparo de Erro de Pareamento de DNA , DNA Fúngico/metabolismo , Mutação , Antígeno Nuclear de Célula em Proliferação/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/genética , Proteínas de Transporte/genética , Cristalografia por Raios X , Replicação do DNA , DNA Fúngico/genética , Proteínas de Ligação a DNA/metabolismo , Edição de Genes , Genes Fúngicos , Proteína 2 Homóloga a MutS/metabolismo , Proteína 3 Homóloga a MutS/metabolismo , Conformação de Ácido Nucleico , Mutação Puntual , Antígeno Nuclear de Célula em Proliferação/fisiologia , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes/metabolismo , Fase S , Proteínas de Saccharomyces cerevisiae/metabolismo , Sumoilação
13.
PLoS Pathog ; 15(4): e1007674, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30958867

RESUMO

Viral myocarditis is a serious disease, commonly caused by type B coxsackieviruses (CVB). Here we show that innate immune protection against CVB3 myocarditis requires the IFIT (IFN-induced with tetratricopeptide) locus, which acts in a biphasic manner. Using IFIT locus knockout (IFITKO) cardiomyocytes we show that, in the absence of the IFIT locus, viral replication is dramatically increased, indicating that constitutive IFIT expression suppresses CVB replication in this cell type. IFNß pre-treatment strongly suppresses CVB3 replication in wild type (wt) cardiomyocytes, but not in IFITKO cardiomyocytes, indicating that other interferon-stimulated genes (ISGs) cannot compensate for the loss of IFITs in this cell type. Thus, in isolated wt cardiomyocytes, the anti-CVB3 activity of IFITs is biphasic, being required for protection both before and after T1IFN signaling. These in vitro findings are replicated in vivo. Using novel IFITKO mice we demonstrate accelerated CVB3 replication in pancreas, liver and heart in the hours following infection. This early increase in virus load in IFITKO animals accelerates the induction of other ISGs in several tissues, enhancing virus clearance from some tissues, indicating that-in contrast to cardiomyocytes-other ISGs can offset the loss of IFITs from those cell types. In contrast, CVB3 persists in IFITKO hearts, and myocarditis occurs. Thus, cardiomyocytes have a specific, biphasic, and near-absolute requirement for IFITs to control CVB infection.


Assuntos
Proteínas de Transporte/fisiologia , Infecções por Coxsackievirus/prevenção & controle , Enterovirus Humano B/patogenicidade , Miocardite/prevenção & controle , Miócitos Cardíacos/enzimologia , Animais , Células Cultivadas , Infecções por Coxsackievirus/metabolismo , Infecções por Coxsackievirus/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocardite/metabolismo , Miocardite/virologia , Proteínas de Ligação a RNA , Replicação Viral
14.
Gene Expr Patterns ; 32: 28-37, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30825522

RESUMO

Midkine (MDK) and Pleiotrophin (PTN) belong to a group of heparin-binding growth factors that has been shown to have pleiotropic functions in various biological processes during development and disease. Development of the vertebrate eye is a multistep process that involves coordinated interactions between neuronal and non-neuronal cells, but very little is known about the potential function of MDK and PTN in these processes. In this study, we demonstrate by section in situ hybridization, the spatiotemporal expression of MDK and PTN during ocular development in chick and mouse. We show that MDK and PTN are expressed in dynamic patterns that overlap in a few non-neuronal tissues in the anterior eye and in neuronal cell layers of the posterior eye. We show that the expression patterns of MDK and PTN are only conserved in a few tissues in chick and mouse but they overlap with the expression of some of their receptors LRP1, RPTPZ, ALK, NOTCH2, ITGß1, SDC1, and SDC3. The dynamic expression patterns of MDK, PTN and their receptors suggest that they function together during the multistep process of ocular development and they may play important roles in cell proliferation, adhesion, and migration of neuronal and non-neuronal cells.


Assuntos
Proteínas de Transporte/metabolismo , Citocinas/metabolismo , Olho/embriologia , Midkina/metabolismo , Animais , Proteínas de Transporte/fisiologia , Proliferação de Células/fisiologia , Embrião de Galinha , Citocinas/fisiologia , Olho/metabolismo , Feminino , Fator 1 de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Heparina/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL/embriologia , Midkina/fisiologia , Gravidez , Retina/embriologia , Fator A de Crescimento do Endotélio Vascular
15.
Chemosphere ; 226: 201-209, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30927672

RESUMO

The mechanism of GSTO1, as a high-risk factor for neurological damage, in sodium fluoride (NaF)-induced learning and memory impairment remained still unclear. Hence, in this study, we used the siRNA-GSTO1 HT22 model to explore the effect of NaF and siRNA-GSTO1 on the viability, and proliferation rate of HT22 cells, as well as the mRNA and protein expression levels of cyclic adenosine monophosphate (cAMP) response element binding protein (CREB), neural cell adhesion molecule (NCAM), stem cell factor (SCF) and brain-derived neurotrophic factor (BDNF). The results of MTT showed that 10-3, 10-4, and 10-5 moL/L sodium fluoride (NaF) exposure could significantly promote the proliferation of HT22 cells at 24 h, 36 h, and 48 h, respectively. In addition, our results showed that exposure to 10-3, 10-4, and 10-5 moL/l NaF increased GSTO1 mRNA and protein expression, but decreased CREB and BDNF expression levels in a dose and time-dependent manner. The mRNA and protein expressions of GSTO1, CREB and BDNF were significantly decreased in the siRNA-GSTO1 and NaF + siRNA-GSTO1 group (P < 0.05). We have shown that various NaF doses affected the learning and memory ability by down-regulation the expressions of CREB, BDNF, NCAM and SCF. In summary, we concluded that GSTO1 plays a mediator role in NaF-induced neurological damage.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Proteínas de Transporte/fisiologia , Glutationa Transferase/fisiologia , Hipocampo/efeitos dos fármacos , Moléculas de Adesão de Célula Nervosa , Fluoreto de Sódio/efeitos adversos , Animais , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas de Transporte/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Linhagem Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulação para Baixo/efeitos dos fármacos , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Transtornos da Memória/induzido quimicamente , Camundongos , Moléculas de Adesão de Célula Nervosa/efeitos dos fármacos , Moléculas de Adesão de Célula Nervosa/metabolismo , Fator de Células-Tronco/efeitos dos fármacos , Fator de Células-Tronco/metabolismo
16.
PLoS Pathog ; 15(3): e1007684, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30883606

RESUMO

Phagocytosis is a complex process that eliminates microbes and is performed by specialised cells such as macrophages. Toll-like receptor 4 (TLR4) is expressed on the surface of macrophages and recognizes Gram-negative bacteria. Moreover, TLR4 has been suggested to play a role in the phagocytosis of Gram-negative bacteria, but the mechanisms remain unclear. Here we have used primary human macrophages and engineered THP-1 monocytes to show that the TLR4 sorting adapter, TRAM, is instrumental for phagocytosis of Escherichia coli as well as Staphylococcus aureus. We find that TRAM forms a complex with Rab11 family interacting protein 2 (FIP2) that is recruited to the phagocytic cups of E. coli. This promotes activation of the actin-regulatory GTPases Rac1 and Cdc42. Our results show that FIP2 guided TRAM recruitment orchestrates actin remodelling and IRF3 activation, two events that are both required for phagocytosis of Gram-negative bacteria.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Fagocitose/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Transporte/fisiologia , Endocitose , Endossomos , Escherichia coli/patogenicidade , Células HEK293 , Humanos , Fator Regulador 3 de Interferon , Lipopolissacarídeos , Macrófagos/imunologia , Macrófagos/metabolismo , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide , Cultura Primária de Células , Transporte Proteico , Transdução de Sinais , Staphylococcus aureus/patogenicidade , Células THP-1 , Receptor 4 Toll-Like/metabolismo , Proteína cdc42 de Ligação ao GTP , Proteínas rab de Ligação ao GTP , Proteínas rac1 de Ligação ao GTP
18.
Dev Cell ; 49(2): 220-234.e8, 2019 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-30905771

RESUMO

Lipid transfer proteins (LTPs) acting at membrane contact sites (MCS) between the ER and other organelles contain domains involved in heterotypic (e.g., ER to Golgi) membrane tethering as well as domains involved in lipid transfer. Here, we show that a long ≈90 aa intrinsically unfolded sequence at the N terminus of oxysterol-binding protein (OSBP) controls OSBP orientation and dynamics at MCS. This Gly-Pro-Ala-rich sequence, whose hydrodynamic radius is twice as that of folded domains, prevents the two PH domains of the OSBP dimer from homotypically tethering two Golgi-like membranes and considerably facilitates OSBP in-plane diffusion and recycling at MCS. Although quite distant in sequence, the N terminus of OSBP-related protein-4 (ORP4) has similar effects. We propose that N-terminal sequences of low complexity in ORPs form an entropic barrier that restrains protein orientation, limits protein density, and facilitates protein mobility in the narrow and crowded MCS environment.


Assuntos
Proteínas de Transporte/metabolismo , Receptores de Esteroides/metabolismo , Proteínas de Transporte/fisiologia , Linhagem Celular , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Células HeLa , Humanos , Lipídeos/fisiologia , Membranas Mitocondriais/metabolismo , Organelas/metabolismo , Domínios Proteicos/fisiologia , Receptores de Esteroides/genética , Receptores de Esteroides/fisiologia , Esteróis/metabolismo
19.
Oncogene ; 38(25): 4915-4931, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30858544

RESUMO

Tumor cells undergo a metabolic shift in order to adapt to the altered microenvironment, although the underlying mechanisms have not been fully explored. HnRNP A1 is involved in the alternative splicing of the pyruvate kinase (PK) mRNA, allowing tumor cells to specifically produce the PKM2 isoform. We found that the acetylation status of hnRNP A1 in hepatocellular carcinoma (HCC) cells was dependent on glucose availability, which affected the PKM2-dependent glycolytic pathway. In the glucose-starved HCC cells, SIRT1 and SIRT6, members of deacetylase sirtuin family, were highly expressed and deacetylated hnRNP A1 after direct binding. We identified four lysine residues in hnRNP A1 that were deacetylated by SIRT1 and SIRT6, resulting in significant inhibition of glycolysis in HCC cells. Deacetylated hnRNP A1 reduced PKM2 and increased PKM1 alternative splicing in HCC cells under normal glucose conditions, thereby reducing the metabolic activity of PK and the non-metabolic PKM2-ß-catenin signaling pathway. However, under glucose starvation, the low levels of acetylated hnRNP A1 reduced HCC cell metabolism to adapt to the nutrient deficiency. Taken together, sirtuin-mediated hnRNP A1 deacetylation inhibits HCC cell proliferation and tumorigenesis in a PKM2-dependent manner. These findings point to the metabolic reprogramming induced by hnRNP A1 acetylation in order to adapt to the nutritional status of the tumor microenvironment.


Assuntos
Acetiltransferases/metabolismo , Carcinoma Hepatocelular/patologia , Glicólise , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Neoplasias Hepáticas/patologia , Sirtuína 1/fisiologia , Sirtuínas/fisiologia , Células A549 , Acetilação , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proteínas de Transporte/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Progressão da Doença , Feminino , Glicólise/genética , Células HCT116 , Células HEK293 , Células Hep G2 , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Pessoa de Meia-Idade , Prognóstico , Processamento de Proteína Pós-Traducional/genética , Hormônios Tireóideos/fisiologia , Microambiente Tumoral/genética
20.
Nat Commun ; 10(1): 1084, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842412

RESUMO

The IRE1α/XBP1 branch of unfolded protein response (UPR) pathway has a critical function in endoplasmic reticulum (ER) expansion in plasma cells via unknown mechanisms; interestingly, another UPR branch, PERK, is suppressed during plasma cell development. Here we show that Ufbp1, a target and cofactor of the ufmylation pathway, promotes plasma cell development by suppressing the activation of PERK. By contrast, the IRE1α/XBP1 axis upregulates the expression of Ufbp1 and ufmylation pathway genes in plasma cells, while Ufbp1 deficiency impairs ER expansion in plasma cells and retards immunoglobulin production. Structure and function analysis suggests that lysine 267 of Ufbp1, the main lysine in Ufbp1 that undergoes ufmylation, is dispensable for the development of plasmablasts, but is required for immunoglobulin production and stimulation of ER expansion in IRE1α-deficient plasmablasts. Thus, Ufbp1 distinctly regulates different branches of UPR pathway to promote plasma cell development and function.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Transporte/fisiologia , Diferenciação Celular , Retículo Endoplasmático/metabolismo , Plasmócitos/fisiologia , Resposta a Proteínas não Dobradas/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/isolamento & purificação , Animais , Linhagem Celular , Endorribonucleases/metabolismo , Feminino , Imunidade Humoral/fisiologia , Lisina/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Cultura Primária de Células , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Regulação para Cima , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/isolamento & purificação , Proteína 1 de Ligação a X-Box/metabolismo , eIF-2 Quinase/metabolismo
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