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1.
Nat Commun ; 11(1): 4627, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009389

RESUMO

Animals have evolved responses to low oxygen conditions to ensure their survival. Here, we have identified the C. elegans zinc finger transcription factor PQM-1 as a regulator of the hypoxic stress response. PQM-1 is required for the longevity of insulin signaling mutants, but surprisingly, loss of PQM-1 increases survival under hypoxic conditions. PQM-1 functions as a metabolic regulator by controlling oxygen consumption rates, suppressing hypoxic glycogen levels, and inhibiting the expression of the sorbitol dehydrogenase-1 SODH-1, a crucial sugar metabolism enzyme. PQM-1 promotes hypoxic fat metabolism by maintaining the expression of the stearoyl-CoA desaturase FAT-7, an oxygen consuming, rate-limiting enzyme in fatty acid biosynthesis. PQM-1 activity positively regulates fat transport to developing oocytes through vitellogenins under hypoxic conditions, thereby increasing survival rates of arrested progeny during hypoxia. Thus, while pqm-1 mutants increase survival of mothers, ultimately this loss is detrimental to progeny survival. Our data support a model in which PQM-1 controls a trade-off between lipid metabolic activity in the mother and her progeny to promote the survival of the species under hypoxic conditions.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Hipóxia/metabolismo , Metabolismo dos Lipídeos , Transativadores/metabolismo , Animais , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica , Glicogênio/metabolismo , Insulina/metabolismo , Larva/metabolismo , Mutação/genética , Consumo de Oxigênio , Transdução de Sinais , Estresse Fisiológico , Análise de Sobrevida , Transativadores/genética , Transcrição Genética , Vitelogeninas/metabolismo
2.
PLoS Pathog ; 16(9): e1008886, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32931525

RESUMO

Citrus canker caused by Xanthomonas citri subsp. citri (Xcc) is one of the most devastating diseases in citrus. Meiwa kumquat (Fortunella crassifolia) has shown a durable resistance against Xcc. Here, we aimed to characterize the mechanisms responsible for such a durable resistance by characterizing the transcriptional and physiological responses of Meiwa kumquat to Xcc. Inoculation of Meiwa kumquat with Xcc promoted immune responses such as upregulation of PR genes, accumulation of salicylic acid, hypersensitive response (HR)-like cell death and early leaf abscission. Hypertrophy and hyperplasia symptoms, which are known to be caused by Xcc-induction of the canker susceptibility gene LOB1 through the transcription activator-like effector (TALE) PthA4, always appear prior to the development of cell death. Mutation of pthA4 in Xcc abolished the induction of LOB1, canker symptoms, cell death, and leaf abscission and reduced the expression of PR genes in inoculated kumquat leaves without reducing Xcc titers in planta. Transcriptome analysis demonstrated that PthA4 promotes plant biotic and abiotic stress responses and the biosynthesis of abscisic acid. Transcriptional induction of LOB1 homologs in Meiwa kumquat by Xcc pthA4 mutant strains carrying a repertoire of designer TALEs promoted the elicitation of HR-like phenotype and leaf abscission, suggesting that kumquat response to Xcc is associated with upregulation of LOB1. Our study suggests a novel mechanism of plant resistance to Xanthomonas via elicitation of immune responses by upregulation of a host susceptibility gene.


Assuntos
Citrus , Genes de Plantas/imunologia , Doenças das Plantas , Imunidade Vegetal , Proteínas de Plantas , Transativadores , Xanthomonas/imunologia , Citrus/genética , Citrus/imunologia , Citrus/microbiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Transativadores/genética , Transativadores/imunologia
3.
Nat Commun ; 11(1): 4653, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938923

RESUMO

Cancer cells demand excess nutrients to support their proliferation, but how tumours exploit extracellular amino acids during systemic metabolic perturbations remain incompletely understood. Here, we use a Drosophila model of high-sugar diet (HSD)-enhanced tumourigenesis to uncover a systemic host-tumour metabolic circuit that supports tumour growth. We demonstrate coordinate induction of systemic muscle wasting with tumour-autonomous Yorkie-mediated SLC36-family amino acid transporter expression as a proline-scavenging programme to drive tumourigenesis. We identify Indole-3-propionic acid as an optimal amino acid derivative to rationally target the proline-dependency of tumour growth. Insights from this whole-animal Drosophila model provide a powerful approach towards the identification and therapeutic exploitation of the amino acid vulnerabilities of tumourigenesis in the context of a perturbed systemic metabolic network.


Assuntos
Açúcares da Dieta/efeitos adversos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Neoplasias Experimentais/fisiopatologia , Prolina/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Animais , Animais Geneticamente Modificados , Carcinogênese , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Larva , Debilidade Muscular/induzido quimicamente , Debilidade Muscular/patologia , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/patologia , Neoplasias Experimentais/etiologia , Proteínas Nucleares/genética , Receptores Proteína Tirosina Quinases/metabolismo , Transativadores/genética , Proteínas ras/genética
4.
Nat Commun ; 11(1): 4455, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901005

RESUMO

Dysregulated alternative splicing (AS) driving carcinogenetic mitosis remains poorly understood. Here, we demonstrate that cancer metastasis-associated antigen 1 (MTA1), a well-known oncogenic chromatin modifier, broadly interacts and co-expresses with RBPs across cancers, contributing to cancerous mitosis-related AS. Using developed fCLIP-seq technology, we show that MTA1 binds abundant transcripts, preferentially at splicing-responsible motifs, influencing the abundance and AS pattern of target transcripts. MTA1 regulates the mRNA level and guides the AS of a series of mitosis regulators. MTA1 deletion abrogated the dynamic AS switches of variants for ATRX and MYBL2 at mitotic stage, which are relevant to mitosis-related tumorigenesis. MTA1 dysfunction causes defective mitotic arrest, leads to aberrant chromosome segregation, and results in chromosomal instability (CIN), eventually contributing to tumorigenesis. Currently, little is known about the RNA splicing during mitosis; here, we uncover that MTA1 binds transcripts and orchestrates dynamic splicing of mitosis regulators in tumorigenesis.


Assuntos
Carcinogênese/genética , Carcinogênese/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , Mitose/fisiologia , RNA Mensageiro/metabolismo , Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Processamento Alternativo , Animais , Sítios de Ligação/genética , Montagem e Desmontagem da Cromatina/genética , Instabilidade Cromossômica , Feminino , Células HCT116 , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Mitose/genética , Neoplasias/genética , Neoplasias/metabolismo , Precursores de RNA/genética , Precursores de RNA/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Transativadores/antagonistas & inibidores , Transativadores/genética
5.
Ann Hematol ; 99(11): 2611-2617, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980888

RESUMO

EP300-ZNF384 fusion is a rare recurrent cytogenetic abnormality associated with B cell acute lymphoblastic leukemia (B-ALL), which was rarely studied in Chinese patient cohort. Here, we used a customized RNA fusion gene panel to investigate gene fusions in 56 selected acute leukemia patients without conventional genetic abnormalities. Two EP300-ZNF384 fusion forms were detected in ten cases, which were in-frame fusions of EP300 exon 6 fused with exon 3 or 2 of ZNF384. The fusions led to the lack of most functional domains of EP300. We firstly reported EP300-ZNF384 fusion in a mixed-phenotype acute leukemia (MPAL) patient whose CD33 and CD13 were negative. The rest nine B-ALL patients with EP300-ZNF384 fusion expressed CD33 and/or CD13. Fifty-six percent of B-ALL patients (5/9) with EP300-ZNF384 fusion were positive with CD10. After the diagnosis of EP300-ZNF384 fusion, 70% of the patients achieved remission after chemotherapy. Our observations indicated that EP300-ZNF384 fusion consists of a distinct subgroup of B-ALL with a characteristic immunophenotype. These patients are sensitive to current chemotherapy regimen and have an excellent outcome.


Assuntos
Proteína p300 Associada a E1A , Proteínas de Fusão Oncogênica , Leucemia-Linfoma Linfoblástico de Células Precursoras , RNA Neoplásico , Análise de Sequência de RNA , Transativadores , Adulto , Estudos de Coortes , Proteína p300 Associada a E1A/genética , Proteína p300 Associada a E1A/metabolismo , Feminino , Humanos , Masculino , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Transativadores/genética , Transativadores/metabolismo
6.
PLoS Genet ; 16(8): e1008963, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32780743

RESUMO

Long-term memory (LTM) formation depends on the conversed cAMP response element-binding protein (CREB)-dependent gene transcription followed by de novo protein synthesis. Thirsty fruit flies can be trained to associate an odor with water reward to form water-reward LTM (wLTM), which can last for over 24 hours without a significant decline. The role of de novo protein synthesis and CREB-regulated gene expression changes in neural circuits that contribute to wLTM remains unclear. Here, we show that acute inhibition of protein synthesis in the mushroom body (MB) αß or γ neurons during memory formation using a cold-sensitive ribosome-inactivating toxin disrupts wLTM. Furthermore, adult stage-specific expression of dCREB2b in αß or γ neurons also disrupts wLTM. The MB αß and γ neurons can be further classified into five different neuronal subsets including αß core, αß surface, αß posterior, γ main, and γ dorsal. We observed that the neurotransmission from αß surface and γ dorsal neuron subsets is required for wLTM retrieval, whereas the αß core, αß posterior, and γ main are dispensable. Adult stage-specific expression of dCREB2b in αß surface and γ dorsal neurons inhibits wLTM formation. In vivo calcium imaging revealed that αß surface and γ dorsal neurons form wLTM traces with different dynamic properties, and these memory traces are abolished by dCREB2b expression. Our results suggest that a small population of neurons within the MB circuits support long-term storage of water-reward memory in Drosophila.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Memória de Longo Prazo/fisiologia , Neurônios/metabolismo , Olfato/genética , Transativadores/genética , Animais , Animais Geneticamente Modificados , Cálcio/metabolismo , Drosophila melanogaster/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Biossíntese de Proteínas/genética , Recompensa , Olfato/fisiologia , Transmissão Sináptica/genética , Água
7.
Chem Biol Interact ; 329: 109222, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32771325

RESUMO

Extensive application of methylene blue (MB) for therapeutic and diagnostic purposes, and reports for unwanted side effects, demand better understanding of the mechanisms of biological action of this thiazine dye. Because MB is redox-active, its biological activities have been attributed to transfer of electrons, generation of reactive oxygen species, and antioxidant action. Results of this study show that MB is more toxic to a superoxide dismutase-deficient Escherichia coli mutant than to its SOD-proficient parent, which indicates that superoxide anion radical is involved. Incubation of E. coli with MB induced the enzymes fumarase C, SOD, nitroreductase A, and glucose-6-phosphate dehydrogenase, all controlled by the soxRS regulon. Induction of these enzymes was prevented by blocking protein synthesis with chloramphenicol and was not observed when soxRS-negative mutants were incubated with MB. These results show that MB is capable of inducing the soxRS regulon of E. coli, which plays a key role in protecting bacteria against oxidative stress and redox-cycling compounds. Irrespective of the abundance of heme-containing proteins in living cells, which are preferred acceptors of electrons from the reduced form of MB, reduction of oxygen to superoxide radical still takes place. Induction of the soxRS regulon suggests that in humans, beneficial effects of MB could be attributed to activation of redox-sensitive transcription factors like Nrf2 and FoxO. If defense systems are compromised or genes coding for protective proteins are not induced, MB would have deleterious effects.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Azul de Metileno/farmacologia , Regulon/efeitos dos fármacos , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Bactérias/genética , Cloranfenicol/farmacologia , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Fumarato Hidratase/genética , Fumarato Hidratase/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Transativadores/genética , Fatores de Transcrição/genética
8.
Mol Cell ; 79(6): 978-990.e5, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32857953

RESUMO

Processing bodies (PBs) and stress granules (SGs) are prominent examples of subcellular, membraneless compartments that are observed under physiological and stress conditions, respectively. We observe that the trimeric PB protein DCP1A rapidly (within ∼10 s) phase-separates in mammalian cells during hyperosmotic stress and dissolves upon isosmotic rescue (over ∼100 s) with minimal effect on cell viability even after multiple cycles of osmotic perturbation. Strikingly, this rapid intracellular hyperosmotic phase separation (HOPS) correlates with the degree of cell volume compression, distinct from SG assembly, and is exhibited broadly by homo-multimeric (valency ≥ 2) proteins across several cell types. Notably, HOPS sequesters pre-mRNA cleavage factor components from actively transcribing genomic loci, providing a mechanism for hyperosmolarity-induced global impairment of transcription termination. Our data suggest that the multimeric proteome rapidly responds to changes in hydration and molecular crowding, revealing an unexpected mode of globally programmed phase separation and sequestration.


Assuntos
Endorribonucleases/genética , Precursores de RNA/genética , Estresse Fisiológico/genética , Transativadores/genética , Terminação da Transcrição Genética , Animais , Tamanho Celular , Sobrevivência Celular/genética , Humanos , Pressão Osmótica/fisiologia , Proteoma/genética
9.
Ann Hematol ; 99(10): 2417-2427, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32862286

RESUMO

For most acute myeloid leukemia (AML) patients, an allogeneic hematopoietic stem cell transplantation (HSCT) offers the highest chance of sustained remissions and long-term survival. At diagnosis, high expression of the AML-associated genes BAALC (brain and acute leukemia, cytoplasmic) and MN1 (meningioma-1) were repeatedly linked to inferior outcomes in patients consolidated with chemotherapy while data for patients receiving HSCT remain limited. Using clinically applicable digital droplet PCR assays, we analyzed the diagnostic BAALC/ABL1 and MN1/ABL1 copy numbers in 302 AML patients. High BAALC/ABL1 and MN1/ABL1 copy numbers associated with common adverse prognostic factors at diagnosis. However, while high diagnostic copy numbers of both genes associated with shorter event free survival (EFS) and overall survival (OS) in patients receiving chemotherapy, there was no prognostic impact in patients undergoing HSCT. Our data suggests that the adverse prognostic impact of high BAALC and MN1 expression are mitigated by allogeneic HSCT. But preHSCT BAALC/ABL1 and MN1/ABL1 assessed in remission prior to HSCT remained prognosticators for EFS and OS independent of the diagnostic expression status. Whether allogeneic HSCT may improve survival for AML patients with high diagnostic BAALC or MN1 expression should be investigated prospectively and may improve informed decisions towards individualized consolidation options in AML.


Assuntos
Medula Óssea/patologia , Leucemia Mieloide Aguda/terapia , Proteínas de Neoplasias/genética , Transplante de Células-Tronco de Sangue Periférico , Transativadores/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aloenxertos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medula Óssea/química , Terapia Combinada , Citarabina/administração & dosagem , Intervalo Livre de Doença , Feminino , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Reação em Cadeia da Polimerase/métodos , Prognóstico , Proteínas Proto-Oncogênicas c-abl/genética , Transativadores/biossíntese , Resultado do Tratamento , Proteínas Supressoras de Tumor/biossíntese , Adulto Jovem
10.
PLoS Genet ; 16(8): e1008965, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760058

RESUMO

The mobilizable resistance island Salmonella genomic island 1 (SGI1) is specifically mobilized by IncA and IncC conjugative plasmids. SGI1, its variants and IncC plasmids propagate multidrug resistance in pathogenic enterobacteria such as Salmonella enterica serovars and Proteus mirabilis. SGI1 modifies and uses the conjugation apparatus encoded by the helper IncC plasmid, thus enhancing its own propagation. Remarkably, although SGI1 needs a coresident IncC plasmid to excise from the chromosome and transfer to a new host, these elements have been reported to be incompatible. Here, the stability of SGI1 and its helper IncC plasmid, each expressing a different fluorescent reporter protein, was monitored using fluorescence-activated cell sorting (FACS). Without selective pressure, 95% of the cells segregated into two subpopulations containing either SGI1 or the helper plasmid. Furthermore, FACS analysis revealed a high level of SGI1-specific fluorescence in IncC+ cells, suggesting that SGI1 undergoes active replication in the presence of the helper plasmid. SGI1 replication was confirmed by quantitative PCR assays, and extraction and restriction of its plasmid form. Deletion of genes involved in SGI1 excision from the chromosome allowed a stable coexistence of SGI1 with its helper plasmid without selective pressure. In addition, deletion of S003 (rep) or of a downstream putative iteron-based origin of replication, while allowing SGI1 excision, abolished its replication, alleviated the incompatibility with the helper plasmid and enabled its cotransfer to a new host. Like SGI1 excision functions, rep expression was found to be controlled by AcaCD, the master activator of IncC plasmid transfer. Transient SGI1 replication seems to be a key feature of the life cycle of this family of genomic islands. Sequence database analysis revealed that SGI1 variants encode either a replication initiator protein with a RepA_C domain, or an alternative replication protein with N-terminal replicase and primase C terminal 1 domains.


Assuntos
Proteínas de Bactérias/genética , Conjugação Genética/genética , Ilhas Genômicas/genética , Fosfoproteínas/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Cromossomos/efeitos dos fármacos , Cromossomos/genética , DNA Helicases/genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Plasmídeos/efeitos dos fármacos , Proteus mirabilis/genética , Salmonella enterica/genética , Transativadores/genética
11.
PLoS One ; 15(8): e0237714, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804961

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious public health problem. There is limited information regarding the genetics of MRSA strains among the native Iraqi and incoming Syrian refugee communities. We aimed to characterize the genotypes and different virulence factors of MRSA in strains isolated from these two communities. Frozen MRSA strains (125) isolated from the native Iraqi and Syrian refugee communities were used in this study. PCR (singleplex and multiplex) and agr typing was used for the genotypic analysis of different virulence genes. We tested for the presence of virulence genes including pvl, arcA, tst, lukE/lukD, hla, hlb, eta, etb and agr. Prevalence of arcA MRSA in the Iraqi community (56.58%) was significantly higher (p = 0.008) than that in the Syrian refugee community (32.66%). Prevalence of lukE-lukD was also significantly higher (p = 0.001) in the Iraqi (82.89%) compared to that in the Syrian refugee community (57.14%). Further, prevalence of hla MRSA in the Iraqi community was (93.4%) and in the Syrian refugee community was (71.4%); (p = 0.0008). No significant differences were observed in the prevalence of pvl, tst, eta, etb and hlb. The most dominant agr types in both Iraqi (76.1% and 10.5%) and Syrian refugee (44.9% and 18.37%) communities were I and III. To sum up, no significant differences were observed between the groups for a majority of virulence factors. This is the first investigation of MRSA genotypes and virulence in both these communities. These results could be useful for further studies that assess the genetic relatedness of strains in the region for epidemiological and monitoring purposes, which would be crucial to limiting the spread of MRSA.


Assuntos
Resistência a Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Refugiados , Infecções Estafilocócicas/microbiologia , Fatores de Virulência/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Cidades/epidemiologia , Exotoxinas/genética , Exotoxinas/isolamento & purificação , Genes Bacterianos/genética , Técnicas de Genotipagem , Humanos , Iraque/epidemiologia , Meticilina/farmacologia , Meticilina/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Prevalência , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Síria , Transativadores/genética , Transativadores/isolamento & purificação , Fatores de Virulência/isolamento & purificação
12.
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
13.
PLoS One ; 15(8): e0233818, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857777

RESUMO

Macrophages serve as a first line of defense against infection with the facultative intracellular pathogen, Cryptococcus neoformans (Cn). However, the ability of these innate phagocytic cells to destroy ingested Cn is strongly influenced by polarization state with classically (M1) activated macrophages better able to control cryptococcal infections than alternatively (M2) activated cells. While earlier studies have demonstrated that intracellular Cn minimally affects the expression of M1 and M2 markers, the impact on the broader transcriptome associated with these states remains unclear. To investigate this, an in vitro cell culture model of intracellular infection together with RNA sequencing-based transcriptome profiling was used to measure the impact of Cn infection on gene expression in both polarization states. The gene expression profile of both M1 and M2 cells was extensively altered to become more like naive (M0) macrophages. Gene ontology analysis suggested that this involved changes in the activity of the Janus kinase-signal transducers and activators of transcription (JAK-STAT), p53, and nuclear factor-κB (NF-κB) pathways. Analyses of the principle polarization markers at the protein-level also revealed discrepancies between the RNA- and protein-level responses. In contrast to earlier studies, intracellular Cn was found to increase protein levels of the M1 marker iNos. In addition, common gene expression changes were identified that occurred post-Cn infection, independent of polarization state. This included upregulation of the transcriptional co-regulator Cited1, which was also apparent at the protein level in M1-polarized macrophages. These changes constitute a transcriptional signature of macrophage Cn infection and provide new insights into how Cn impacts gene expression and the phenotype of host phagocytes.


Assuntos
Cryptococcus neoformans/patogenicidade , Macrófagos/metabolismo , Macrófagos/microbiologia , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Cryptococcus neoformans/imunologia , Ontologia Genética , Redes Reguladoras de Genes , Imunidade Inata/genética , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Camundongos , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Transativadores/genética , Transativadores/metabolismo , Transcriptoma
14.
J Clin Pathol ; 73(9): 527-530, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32699115

RESUMO

The GLIS 1-3 genes belong to a family of transcription factors, the Krüppel-like zinc finger proteins. The GLIS proteins function primarily as activators of transcription (GLIS 1 and 3), while GLIS 2 functions as a repressor. Collectively, the GLIS proteins are involved in a variety of diseases in several organs ranging from Alzheimer's disease, facial dysmorphism, neonatal diabetes mellitus, breast and colon cancers and leukaemia. In particular, loss-of-function mutations in GLIS2 are responsible for an autosomal recessive cystic kidney disease called nephronophthisis, which is characterised by tubular atrophy, interstitial fibrosis and corticomedullary cysts.Of diagnostic value in current practice are the presence of GLIS 3 and 1 fusions with PAX8 in almost 100% of hyalinising trabecular tumours of the thyroid gland. This enables its separation from papillary thyroid cancer.


Assuntos
Proteínas de Ligação a DNA/genética , Fatores de Transcrição Kruppel-Like/genética , Proteínas Repressoras/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Transativadores/genética , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/metabolismo , Fusão Gênica , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Mutação com Perda de Função , Fator de Transcrição PAX8/genética , Fator de Transcrição PAX8/metabolismo , Proteínas Repressoras/metabolismo , Glândula Tireoide/patologia , Transativadores/metabolismo , Fatores de Transcrição/metabolismo
15.
Gene ; 757: 144938, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32640305

RESUMO

Myb-like SWIRM and MPN domains (MYSM1) is a chromatin-binding transcriptional regulator that mediates histone 2A deubiquitination, which plays a vital role in hematopoiesis and lymphocyte differentiation. Biallelic variants in MYSM1 cause a rare bone marrow failure syndrome (OMIM #618116). To date, only three pathogenic variants (E390*, R478*, and H656R) of MYSM1 have been reported in nine patients, and all variants are homozygous. Here, we describe a Chinese female patient who mainly presented with leukopenia, granulocytopenia, thrombocytopenia, severe anemia, and B-cell and natural killer cell deficiency in the peripheral blood, and was diagnosed with bone marrow failure. Trio whole-exome sequencing revealed a novel compound heterozygous variant in MYSM1 (c.399G > A, p.L133L, and c.1467C > G, p.Y489*). The c.399G > A synonymous variant is located at the 3'-end of exon 6, which is predicted to affect MYSM1 mRNA splicing. Analysis of the products obtained from the reverse transcription-polymerase chain reaction revealed that the c.399G > A variant leads to exon 6 skipping, resulting in a premature termination codon (c.321_399 del, p.V108Lfs*13). cDNA sequencing suggested that the c.1467C > G variant triggered nonsense-mediated mRNA degradation. Moreover, we identified a novel transcript of MYSM1 mRNA (missing exons 5 and 6) in human blood cells. Our results expand the mutation spectrum of MYSM1; additionally, this is the first report of a synonymous splicing variant that induces post-transcriptional skipping of exon 6 leading to a bone marrow failure syndrome phenotype.


Assuntos
Síndrome Congênita de Insuficiência da Medula Óssea/genética , Mutação , Transativadores/genética , Proteases Específicas de Ubiquitina/genética , Síndrome Congênita de Insuficiência da Medula Óssea/patologia , Feminino , Células HEK293 , Heterozigoto , Humanos , Lactente , Processamento de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transativadores/metabolismo , Proteases Específicas de Ubiquitina/metabolismo
16.
Nat Commun ; 11(1): 3354, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620797

RESUMO

Expansion of an intronic (GGGGCC)n repeat region within the C9orf72 gene is a main cause of familial amyotrophic lateral sclerosis and frontotemporal dementia (c9ALS/FTD). A hallmark of c9ALS/FTD is the accumulation of misprocessed RNAs, which are often targets of cellular RNA surveillance. Here, we show that RNA decay mechanisms involving upstream frameshift 1 (UPF1), including nonsense-mediated decay (NMD), are inhibited in c9ALS/FTD brains and in cultured cells expressing either of two arginine-rich dipeptide repeats (R-DPRs), poly(GR) and poly(PR). Mechanistically, although R-DPRs cause the recruitment of UPF1 to stress granules, stress granule formation is independent of NMD inhibition. Instead, NMD inhibition is primarily a result from global translational repression caused by R-DPRs. Overexpression of UPF1, but none of its NMD-deficient mutants, enhanced the survival of neurons treated by R-DPRs, suggesting that R-DPRs cause neurotoxicity in part by inhibiting cellular RNA surveillance.


Assuntos
Esclerose Amiotrófica Lateral/genética , Proteína C9orf72/genética , Demência Frontotemporal/genética , Degradação do RNAm Mediada por Códon sem Sentido , RNA Helicases/metabolismo , Transativadores/metabolismo , Esclerose Amiotrófica Lateral/patologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Expansão das Repetições de DNA , Conjuntos de Dados como Assunto , Embrião de Mamíferos , Feminino , Lobo Frontal/patologia , Demência Frontotemporal/patologia , Humanos , Íntrons/genética , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Cultura Primária de Células , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , RNA-Seq , Transativadores/genética
17.
PLoS One ; 15(7): e0236101, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32678829

RESUMO

Dysregulation of histone demethylase Jumonji-C domain-containing protein 5 (JMJD5) has been identified as a great effect on tumorigenesis. Silibinin is a commonly used anti-hepatotoxic drug and exhibits anticancer effect in various cancers. However, the antitumor mechanism between silibinin and JMJD5 in oral squamous cell carcinoma (OSCC) remains unclear. In this study, the clinical significance of JMJD5 on OSCC patients was assessed through tissue microarray. Furthermore, mice bearing patient-derived tumor xenografts (PDTXs) and tongue cancer cell lines were treated with silibinin and evaluated for tumor growth and JMJD5 expression. High expression of JMJD5 in oral cancer was significantly associated with tumor size (P = 0.0241), cervical node metastasis (P = 0.0001) and clinical stage (P = 0.0002), was associated with worse survival rate compared with that of the total cohort (P = 0.0002). Collectively the data indicate that JMJD5 expression may be suitable for detection of unfavorable prognosis in OSCC patients, based in part on its apparent role as a marker of metastasis. In addition, silibinin inhibits cancer growth in vitro and in PDTX models. Furthermore, metastasis-associated protein 1 (MTA1) could regulate the expression for JMJD5 and had a positive correlation with JMJD5. Moreover, silibinin could downregulate JMJD5 and MTA1 in oral cancer. Present study thus identifies that JMJD5 might be an essential prognostic indicator and therapeutic target against OSCC progression. In addition, silibinin is a potential candidate among novel chemotherapeutic agents or adjuvants for modulating JMJD5 in OSCC, through a mechanism likely involving MTA1/JMJD5 axis.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Histona Desmetilases/metabolismo , Neoplasias Bucais/patologia , Proteínas Repressoras/metabolismo , Silibina/farmacologia , Transativadores/metabolismo , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/genética , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Prognóstico , Proteínas Repressoras/genética , Taxa de Sobrevida , Transativadores/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Nat Commun ; 11(1): 3345, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620802

RESUMO

Nonsense-mediated mRNA decay (NMD) is an evolutionarily conserved RNA decay mechanism that has emerged as a potent cell-intrinsic restriction mechanism of retroviruses and positive-strand RNA viruses. However, whether NMD is capable of restricting DNA viruses is not known. The DNA virus Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiological agent of Kaposi's sarcoma and primary effusion lymphoma (PEL). Here, we demonstrate that NMD restricts KSHV lytic reactivation. Leveraging high-throughput transcriptomics we identify NMD targets transcriptome-wide in PEL cells and identify host and viral RNAs as substrates. Moreover, we identified an NMD-regulated link between activation of the unfolded protein response and transcriptional activation of the main KSHV transcription factor RTA, itself an NMD target. Collectively, our study describes an intricate relationship between cellular targets of an RNA quality control pathway and KSHV lytic gene expression, and demonstrates that NMD can function as a cell intrinsic restriction mechanism acting upon DNA viruses.


Assuntos
Regulação Viral da Expressão Gênica , Herpesvirus Humano 8/genética , Degradação do RNAm Mediada por Códon sem Sentido , RNA Viral/metabolismo , Ativação Viral/genética , Linhagem Celular Tumoral , Células HEK293 , Herpesvirus Humano 8/metabolismo , Herpesvirus Humano 8/patogenicidade , Interações Hospedeiro-Patógeno/genética , Humanos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Linfoma de Efusão Primária/genética , Linfoma de Efusão Primária/virologia , RNA Mensageiro/metabolismo , RNA-Seq , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/virologia , Transativadores/genética , Transativadores/metabolismo , Ativação Transcricional , Resposta a Proteínas não Dobradas/genética , Latência Viral/genética
19.
Proc Natl Acad Sci U S A ; 117(28): 16516-16526, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601179

RESUMO

LIN28B is highly expressed in neuroblastoma and promotes tumorigenesis, at least, in part, through inhibition of let-7 microRNA biogenesis. Here, we report that overexpression of either wild-type (WT) LIN28B or a LIN28B mutant that is unable to inhibit let-7 processing increases the penetrance of MYCN-induced neuroblastoma, potentiates the invasion and migration of transformed sympathetic neuroblasts, and drives distant metastases in vivo. Genome-wide chromatin immunoprecipitation coupled with massively parallel DNA sequencing (ChIP-seq) and coimmunoprecipitation experiments show that LIN28B binds active gene promoters in neuroblastoma cells through protein-protein interaction with the sequence-specific zinc-finger transcription factor ZNF143 and activates the expression of downstream targets, including transcription factors forming the adrenergic core regulatory circuitry that controls the malignant cell state in neuroblastoma as well as GSK3B and L1CAM that are involved in neuronal cell adhesion and migration. These findings reveal an unexpected let-7-independent function of LIN28B in transcriptional regulation during neuroblastoma pathogenesis.


Assuntos
Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transativadores/metabolismo , Animais , Animais Geneticamente Modificados , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/fisiopatologia , Ligação Proteica , Proteínas de Ligação a RNA/genética , Transativadores/genética , Peixe-Zebra
20.
Mol Cell Biol ; 40(18)2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32631903

RESUMO

Precursor B cell acute lymphoblastic leukemia (B-ALL) is caused by genetic lesions in developing B cells that function as drivers for the accumulation of additional mutations in an evolutionary selection process. We investigated secondary drivers of leukemogenesis in a mouse model of B-ALL driven by PU.1/Spi-B deletion (Mb1-CreΔPB). Whole-exome-sequencing analysis revealed recurrent mutations in Jak3 (encoding Janus kinase 3), Jak1, and Ikzf3 (encoding Aiolos). Mutations with a high variant-allele frequency (VAF) were dominated by C→T transition mutations that were compatible with activation-induced cytidine deaminase, whereas the majority of mutations, with a low VAF, were dominated by C→A transversions associated with 8-oxoguanine DNA damage caused by reactive oxygen species (ROS). The Janus kinase (JAK) inhibitor ruxolitinib delayed leukemia onset, reduced ROS and ROS-induced gene expression signatures, and altered ROS-induced mutational signatures. These results reveal that JAK mutations can alter the course of leukemia clonal evolution through ROS-induced DNA damage.


Assuntos
Dano ao DNA , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Leucemia de Células B/metabolismo , Animais , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Janus Quinase 3/metabolismo , Leucemia de Células B/genética , Leucemia de Células B/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Proto-Oncogênicas c-ets/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transativadores/genética , Transativadores/metabolismo
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