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1.
Mem Inst Oswaldo Cruz ; 115: e200142, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33053076

RESUMO

BACKGROUND: Calpains are present in almost all organisms and comprise a family of calcium-dependent cysteine peptidases implicated in crucial cellular functions. Trypanosoma cruzi, the causative agent of Chagas disease, presents an expansion on this gene family with unexplored biological properties. OBJECTIVES: Here, we searched for calpains in the T. cruzi genome, evaluated the mRNA levels, calpain activity and the protein expression and determined the cellular localisation in all three parasite life cycle forms. METHODS/FINDINGS: Sixty-three calpain sequences were identified in T. cruzi CL Brener genome, with fourteen domain arrangements. The comparison of calpain mRNA abundance by quantitative polymerase chain reaction (qPCR) revealed seven up-regulated sequences in amastigotes and/or bloodstream trypomastigotes and five in epimastigotes. Western Blotting analysis revealed seven different molecules in the three parasite forms, and one amastigote-specific, while no proteolytic activity could be detected. Flow cytometry assays revealed a higher amount of intracellular calpains in amastigotes and/or trypomastigotes in comparison to epimastigotes. Finally, ultrastructural analysis revealed the presence of calpains in the cytoplasm, vesicular and plasma membranes of the three parasite forms, and in the paraflagellar rod in trypomastigotes. CONCLUSION: Calpains are differentially expressed and localised in the T. cruzi life cycle forms. This study adds data on the calpain occurrence and expression pattern in T. cruzi.


Assuntos
Calpaína/genética , Trypanosoma cruzi/genética , Animais , Western Blotting , Calpaína/metabolismo , Doença de Chagas , Estágios do Ciclo de Vida , RNA Mensageiro/genética
2.
Mol Cell ; 80(1): 156-163.e6, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007255

RESUMO

The production of alternative RNA variants contributes to the tissue-specific regulation of gene expression. In the animal nervous system, a systematic shift toward distal sites of transcription termination produces transcript signatures that are crucial for neuron development and function. Here, we report that, in Drosophila, the highly conserved protein ELAV globally regulates all sites of neuronal 3' end processing and directly binds to proximal polyadenylation sites of target mRNAs in vivo. We uncover an endogenous strategy of functional gene rescue that safeguards neuronal RNA signatures in an ELAV loss-of-function context. When not directly repressed by ELAV, the transcript encoding the ELAV paralog FNE acquires a mini-exon, generating a new protein able to translocate to the nucleus and rescue ELAV-mediated alternative polyadenylation and alternative splicing. We propose that exon-activated functional rescue is a more widespread mechanism that ensures robustness of processes regulated by a hierarchy, rather than redundancy, of effectors.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Éxons/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Masculino , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética
3.
Mol Cell ; 80(1): 140-155.e6, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007254

RESUMO

The tissue-specific deployment of highly extended neural 3' UTR isoforms, generated by alternative polyadenylation (APA), is a broad and conserved feature of metazoan genomes. However, the factors and mechanisms that control neural APA isoforms are not well understood. Here, we show that three ELAV/Hu RNA binding proteins (Elav, Rbp9, and Fne) have similar capacities to induce a lengthened 3' UTR landscape in an ectopic setting. These factors promote accumulation of chromatin-associated, 3' UTR-extended, nascent transcripts, through inhibition of proximal polyadenylation site (PAS) usage. Notably, Elav represses an unannotated splice isoform of fne, switching the normally cytoplasmic Fne toward the nucleus in elav mutants. We use genomic profiling to reveal strong and broad loss of neural APA in elav/fne double mutant CNS, the first genetic background to largely abrogate this distinct APA signature. Overall, we demonstrate how regulatory interplay and functionally overlapping activities of neural ELAV/Hu RBPs drives the neural APA landscape.


Assuntos
Regiões 3' não Traduzidas/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Neurônios/metabolismo , Processamento Alternativo/genética , Motivos de Aminoácidos , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Proteínas ELAV/química , Larva/metabolismo , Mutação/genética , Poli A/metabolismo , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
4.
Nat Commun ; 11(1): 4956, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009383

RESUMO

Tet-enzyme-mediated 5-hydroxymethylation of cytosines in DNA plays a crucial role in mouse embryonic stem cells (ESCs). In RNA also, 5-hydroxymethylcytosine (5hmC) has recently been evidenced, but its physiological roles are still largely unknown. Here we show the contribution and function of this mark in mouse ESCs and differentiating embryoid bodies. Transcriptome-wide mapping in ESCs reveals hundreds of messenger RNAs marked by 5hmC at sites characterized by a defined unique consensus sequence and particular features. During differentiation a large number of transcripts, including many encoding key pluripotency-related factors (such as Eed and Jarid2), show decreased cytosine hydroxymethylation. Using Tet-knockout ESCs, we find Tet enzymes to be partly responsible for deposition of 5hmC in mRNA. A transcriptome-wide search further reveals mRNA targets to which Tet1 and Tet2 bind, at sites showing a topology similar to that of 5hmC sites. Tet-mediated RNA hydroxymethylation is found to reduce the stability of crucial pluripotency-promoting transcripts. We propose that RNA cytosine 5-hydroxymethylation by Tets is a mark of transcriptome flexibility, inextricably linked to the balance between pluripotency and lineage commitment.


Assuntos
5-Metilcitosina/análogos & derivados , Diferenciação Celular , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , RNA/metabolismo , 5-Metilcitosina/metabolismo , Animais , Especificidade de Anticorpos/imunologia , Sequência de Bases , Corpos Embrioides/metabolismo , Camundongos , Modelos Biológicos , Células-Tronco Pluripotentes/metabolismo , Ligação Proteica , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética
5.
Medicine (Baltimore) ; 99(40): e21503, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33019382

RESUMO

Hepatitis B virus (HBV) infection is a leading cause of hepatocellular carcinoma (HCC), but HBV-HCC related prognosis signature remains rarely investigated. This study was to identify an integrated long non-coding RNAs-messenger RNAs (lncRNA-mRNA) signature for prediction of overall survival (OS) and explore their underlying functions.One RNA-sequencing dataset (training set, n = 95) and one microarray dataset E-TABM-36 (validation set, n = 44) were collected. Least absolute shrinkage and selection operator analysis was performed to identify an lncRNA-mRNA prognosis signature. The OS difference of patients in the high-risk and low-risk risk groups was evaluated by Kaplan-Meier curve. Area under the receiver operating characteristic curve (AUC), Harrell concordance index (C-index) calculation, and multivariate analyses with clinical characteristics were used to determine the prognostic ability. Furthermore, a coexpression network was constructed to interpret the functions.Nine signature genes (3 lncRNAs and 6 mRNAs) were selected to generate the risk score model. Patients belonging to the high-risk group showed a significantly shorter survival than those of the low-risk group. The prediction accuracy of the risk score for 5-year OS was 0.936 and 0.905 for the training set and validation set, respectively. Also, this risk score was independent of various clinical variables for the prognosis prediction. Incorporation of the risk score remarkably increased the predictive power of the routine clinical prognostic factors (vascular invasion status, tumor recurrence status) (AUC = 0.942 vs 0.628; C-index = 0.7997 vs 0.6908). Furthermore, LncRNA insulin-like growth factor 2 antisense RNA (IGF2-AS) and long intergenic non-protein coding RNA 342 (LINC00342) were predicted to exert tumor suppression effects by regulating homeobox D1 (HOXD1) and secreted frizzled related protein 5 (SFRP5), respectively; while lncRNA rhophilin Rho GTPase binding protein 1 antisense RNA 1 (RHPN1-AS1) may possess carcinogenic potential by promoting the transcription of chromobox 2 (CBX2), cell division cycle 20 (CDC20), matrix metallopeptidase 12 (MMP12), stratifin (SFN), tripartite motif containing 16 (TRIM16), and uroplakin 3A (UPK3A). These mRNAs may be associated with cell proliferation or apoptosis related pathways.This study may provide a novel, effective prognostic biomarker, and some therapeutic targets for HBV-HCC patients.


Assuntos
Carcinoma Hepatocelular/genética , Hepatite B/genética , Neoplasias Hepáticas/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Idoso , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Medição de Risco
6.
Anim Sci J ; 91(1): e13456, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32926548

RESUMO

In this study, we investigated whether bovine oviducts and endometria produce anti-Müllerian hormone (AMH) (for paracrine and autocrine signaling). Reverse transcription-polymerase chain reaction and western blotting detected AMH expression in oviductal and endometrial specimens. Immunohistochemistry revealed robust AMH expression in the ampulla and isthmus epithelia, and the glandular and luminal endometrial epithelia (caruncular endometria). AMH mRNA (measured by real-time PCR) and protein expression in these layers did not significantly differ among estrous phases in adult Japanese Black (JB) heifers (p > .1). Furthermore, the expression in these layers also did not differ among Holstein cows (93.8 ± 5.8 months old), JB heifers (25.5 ± 0.4 months old), and JB cows (97.9 ± 7.9 months old). We also compared AMH concentrations in the oviduct and uterine horn fluids among the three groups (measured by immunoassays). Interestingly, the AMH concentration in the oviduct fluid, but not in the uterine horn fluid, of Holstein cows was lower than those in JB heifers and cows (p < .05). Therefore, bovine oviducts and endometria express AMH and likely secrete it into the oviduct and uterine fluids.


Assuntos
Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Endométrio/metabolismo , Células Epiteliais/metabolismo , Expressão Gênica , Oviductos/metabolismo , Animais , Bovinos , Endométrio/citologia , Ciclo Estral/metabolismo , Feminino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Útero/metabolismo
7.
Zhonghua Zhong Liu Za Zhi ; 42(8): 629-634, 2020 Aug 23.
Artigo em Chinês | MEDLINE | ID: mdl-32867453

RESUMO

Objective: To investigate the effect of esculin on the proliferation of triple negative breast cancer cells and its molecular mechanism. Methods: MDA-MB-231 cells were treated with 28, 56, 112, 225, 450 and 900 µmol/L of esculin for 24, 48 and 72 h, respectively, and the cell viability was detected by cell counting kit 8 (CCK-8) assay. In addition, MDA-MB-231 cells were treated with 0, 225, 450 and 900 µmol/L of esculin for 48 h. And then the changes in cell morphology were observed by inverted microscope. The clone-forming ability was detected by colony formation assay. The mRNA expression levels of FBI-1, p53 and p21 were detected using real-time fluorescence quantitative polymerase chain reaction. The protein expression levels of FBI-1, p53, p21 and Ki67 were detected by western blot. Results: Compared with the blank control group, the cell viability of MDA-MB-231 cells that treated with esculin significantly decreased in a dose-dependent and time-dependent manners. After treatment with esculin, MDA-MB-231 cells shrunk, flattened, adhered poorly to the culture dish and the cell spacing became larger. Meanwhile, shedding and incomplete cells appeared, of which 900 µmol/L of esculin treatment group showed the most dramatic changes. In addition, the colony formation ratios were decreased to (77.18±5.13)%, (65.94±4.98)% and (45.92±3.70)% in the 225, 450 and 900 µmol/L of esculin treatment groups compared with blank control, respectively (P<0.01). Furthermore, the mRNA and protein expressions of FBI-1 increased, while the levels of p53 and p21 mRNA and protein, as well as the protein expression of Ki67 decreased in a concentration-dependent manner (P<0.01). Conclusion: Esculin may regulate cell cycle-related p53-p21 pathway via FBI-1 mediated DNA replication, thus inhibit the proliferation of triple negative breast cancer cells.


Assuntos
Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Esculina/farmacologia , RNA Mensageiro/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias da Mama/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Proteínas de Ligação a DNA , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Fatores de Transcrição , Neoplasias de Mama Triplo Negativas/patologia
8.
Acta Odontol Latinoam ; 33(2): 125, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920615

RESUMO

Melatonin (MLT) is a potential signaling molecule in the homeostasis of bone metabolism and may be an important mediator of bone formation and stimulation. The aim of this in vitro study was to evaluate the effect of MLT on the viability, mRNA/protein expression and mineralization of pre-osteoblastic cells. The concentrations 5, 2.5, 1, 0.1 and 0.01 mM MLT were tested on pre-osteoblastic cells (MC3T3) compared to control (no MLT), evaluating proliferation and cell viability (C50), gene expression (RT-PCR) and secretion (ELISA) of COL-I and OPN at 24h, 48h and 72h, and the formation of mineral nodules (alizarin red and fast red) after 10 days of treatment. MLT at 5 and 2.5 mM proved to be cytotoxic (C50), so only 0.01, 0.1 and 1 mM were used for the subsequent analyses. OPN mRNA expression increased with MLT at 0.1 mM - 1 mM, which was followed by increased secretion of OPN both at 24h and 72h compared to the remaining groups (p <0.05). COL-I mRNA and COL-1 secretion followed the same pattern as OPN at 0.1 mM MLT at 72h of treatment (p <0.05). Regarding mineralization, all MLT doses (except 1mM) caused an increase (p <0.05) in the formation of mineral nodules compared to the control. Melatonin at 0.01mM - 1mM had a stimulatory effect on osteoblasts by upregulating COL-I and OPN expression/ secretion and mineralization, thereby fostering osteogenesis.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Metaloproteinase 2 da Matriz/metabolismo , Melatonina/farmacologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteopontina/metabolismo , Fragmentos de Peptídeos/metabolismo , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/genética , Osteoblastos/metabolismo , Osteopontina/genética , Fragmentos de Peptídeos/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real
9.
Nature ; 585(7824): 239-244, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32879485

RESUMO

Obligate endosymbiosis, in which distantly related species integrate to form a single replicating individual, represents a major evolutionary transition in individuality1-3. Although such transitions are thought to increase biological complexity1,2,4-6, the evolutionary and developmental steps that lead to integration remain poorly understood. Here we show that obligate endosymbiosis between the bacteria Blochmannia and the hyperdiverse ant tribe Camponotini7-11 originated and also elaborated through radical alterations in embryonic development, as compared to other insects. The Hox genes Abdominal A (abdA) and Ultrabithorax (Ubx)-which, in arthropods, normally function to differentiate abdominal and thoracic segments after they form-were rewired to also regulate germline genes early in development. Consequently, the mRNAs and proteins of these Hox genes are expressed maternally and colocalize at a subcellular level with those of germline genes in the germplasm and three novel locations in the freshly laid egg. Blochmannia bacteria then selectively regulate these mRNAs and proteins to make each of these four locations functionally distinct, creating a system of coordinates in the embryo in which each location performs a different function to integrate Blochmannia into the Camponotini. Finally, we show that the capacity to localize mRNAs and proteins to new locations in the embryo evolved before obligate endosymbiosis and was subsequently co-opted by Blochmannia and Camponotini. This pre-existing molecular capacity converged with a pre-existing ecological mutualism12,13 to facilitate both the horizontal transfer10 and developmental integration of Blochmannia into Camponotini. Therefore, the convergence of pre-existing molecular capacities and ecological interactions-as well as the rewiring of highly conserved gene networks-may be a general feature that facilitates the origin and elaboration of major transitions in individuality.


Assuntos
Formigas/embriologia , Formigas/microbiologia , Bactérias , Evolução Biológica , Regulação da Expressão Gênica no Desenvolvimento/genética , Individualidade , Simbiose/genética , Animais , Formigas/citologia , Formigas/genética , Desenvolvimento Embrionário/genética , Feminino , Genes Homeobox/genética , Herança Materna/genética , Oócitos/citologia , Oócitos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Nat Commun ; 11(1): 4607, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929081

RESUMO

Drug tolerance is the basis for acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) including osimertinib, through mechanisms that still remain unclear. Here, we show that while AXL-low expressing EGFR mutated lung cancer (EGFRmut-LC) cells are more sensitive to osimertinib than AXL-high expressing EGFRmut-LC cells, a small population emerge osimertinib tolerance. The tolerance is mediated by the increased expression and phosphorylation of insulin-like growth factor-1 receptor (IGF-1R), caused by the induction of its transcription factor FOXA1. IGF-1R maintains association with EGFR and adaptor proteins, including Gab1 and IRS1, in the presence of osimertinib and restores the survival signal. In AXL-low-expressing EGFRmut-LC cell-derived xenograft and patient-derived xenograft models, transient IGF-1R inhibition combined with continuous osimertinib treatment could eradicate tumors and prevent regrowth even after the cessation of osimertinib. These results indicate that optimal inhibition of tolerant signals combined with osimertinib may dramatically improve the outcome of EGFRmut-LC.


Assuntos
Acrilamidas/uso terapêutico , Compostos de Anilina/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Acrilamidas/farmacologia , Idoso de 80 Anos ou mais , Compostos de Anilina/farmacologia , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Imidazóis/farmacologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Pirazinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Regulação para Cima/efeitos dos fármacos
11.
Medicine (Baltimore) ; 99(38): e22261, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32957376

RESUMO

Pancreatic cancer (PC) is one of the major causes of cancer mortality in developed countries. Therefore, there is an urgent need to derive biomarkers for early diagnosis of PC patients at high risk.This study was designed to identify a panel of miRNAs that might serve as biomarkers for the early diagnosis of PC.The data containing both PC and control samples were extracted from the Gene Expression Omnibus (GEO) database. EdgeR was applied to identify the differentially expressed miRNAs and genes between PC patients and healthy controls. Then a miRNA-mRNA network was constructed based on the differentially expressed miRNAs and genes. The miRNAs-based biomarker for PC was finally constructed by random forest. Finally, AUC was used to evaluate the performance of miRNAs to classify PC and control samples.A total of 33 differentially expressed miRNAs, 753 differentially expressed genes, and 8 miRNAs (hsa-mir-139, hsa-mir-31, hsa-mir-196b, hsa-mir-221, hsa-mir-203b, hsa-mir-215, hsa-mir-144, and hsa-mir-4433b) that play important roles in PC were identified. The target genes of these miRNAs were found to be mainly enriched in negative regulation of acute inflammatory response cell-substrate responses, and o-glycan processing pathways. The constructed biomarkers based on these 8 miRNAs could distinguish samples coming from PC and healthy controls.We identified a panel of eight-miRNAs that would serve as early diagnostic biomarkers for PC patients.


Assuntos
Biomarcadores Tumorais/genética , Detecção Precoce de Câncer , MicroRNAs/genética , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Perfilação da Expressão Gênica , Humanos , Prognóstico , RNA Mensageiro/genética
12.
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
13.
PLoS Pathog ; 16(8): e1008845, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866210

RESUMO

Modified vaccinia virus Ankara (MVA) is an approved smallpox vaccine and a promising vaccine vector for other pathogens as well as for cancer therapeutics with more than 200 current or completed clinical trials. MVA was derived by passaging the parental Ankara vaccine virus hundreds of times in chick embryo fibroblasts during which it lost the ability to replicate in human and most other mammalian cells. Although this replication deficiency is an important safety feature, the genetic basis of the host restriction is not understood. Here, an unbiased human genome-wide RNAi screen in human A549 cells revealed that the zinc-finger antiviral protein (ZAP), previously shown to inhibit certain RNA viruses, is a host restriction factor for MVA, a DNA virus. Additional studies demonstrated enhanced MVA replication in several human cell lines following knockdown of ZAP. Furthermore, CRISPR-Cas9 knockout of ZAP in human A549 cells increased MVA replication and spread by more than one log but had no effect on a non-attenuated strain of vaccinia virus. The intact viral C16 protein, which had been disrupted in MVA, antagonized ZAP by binding and sequestering the protein in cytoplasmic punctate structures. Studies aimed at exploring the mechanism by which ZAP restricts MVA replication in the absence of C16 showed that knockout of ZAP had no discernible effect on viral DNA or individual mRNA or protein species as determined by droplet digital polymerase chain reaction, deep RNA sequencing and mass spectrometry, respectively. Instead, inactivation of ZAP reduced the number of aberrant, dense, spherical particles that typically form in MVA-infected human cells, suggesting that ZAP has a novel role in interfering with a late step in the assembly of infectious MVA virions in the absence of the C16 protein.


Assuntos
Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/metabolismo , Vírus Vaccinia/fisiologia , Replicação Viral/fisiologia , Células A549 , Animais , Galinhas , Citoplasma/metabolismo , Citoplasma/virologia , DNA Viral/genética , DNA Viral/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Proteínas de Ligação a RNA/genética , RNA-Seq , Proteínas Repressoras/genética
14.
Anticancer Res ; 40(10): 5777-5785, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988905

RESUMO

BACKGROUND/AIM: Emerging evidence suggests that Insulin-like growth factor II mRNA-binding protein 3 (IMP3) promotes tumor progression in several human malignancies. We investigated whether IMP3 expression has clinicopathological and prognostic significance in gallbladder adenocarcinoma (GBAC). PATIENTS AND METHODS: We examined immunohistochemical IMP3 expression in 204 GBACs and its associations with clinicopathological parameters and patient outcomes. RESULTS: The majority (87.7%) of GBACs exhibited at least focal cytoplasmic and membranous IMP3 immunoreactivity. Tumor-specific IMP3 expression highlighted proper muscle invasion, which was not detected in the corresponding hematoxylin and eosin-stained slides. This finding upgraded pathological tumor stage (pT) from pT1a to pT1b in four well-differentiated GBACs. High IMP3 expression was associated with high histological grade, advanced stage, and lymphatic invasion, as well as worse overall survival. CONCLUSION: Tumor-specific IMP3 expression in GBAC is helpful in determining the tumor extent, especially in well-differentiated tumors. High IMP3 expression reflects aggressive oncogenic behavior of GBAC. IMP3 expression may be used as a diagnostic and prognostic marker in GBAC.


Assuntos
Carcinoma/genética , Neoplasias da Vesícula Biliar/genética , Prognóstico , Proteínas de Ligação a RNA , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma/patologia , Feminino , Neoplasias da Vesícula Biliar/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética
15.
Nat Commun ; 11(1): 4827, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973167

RESUMO

In bacteria, translation re-initiation is crucial for synthesizing proteins encoded by genes that are organized into operons. The mechanisms regulating translation re-initiation remain, however, poorly understood. We now describe the ribosome termination structure (RTS), a conserved and stable mRNA secondary structure localized immediately downstream of stop codons, and provide experimental evidence for its role in governing re-initiation efficiency in a synthetic Escherichia coli operon. We further report that RTSs are abundant, being associated with 18%-65% of genes in 128 analyzed bacterial genomes representing all phyla, and are selectively depleted when translation re-initiation is advantageous yet selectively enriched so as to insulate translation when re-initiation is deleterious. Our results support a potentially universal role for the RTS in controlling translation termination-insulation and re-initiation across bacteria.


Assuntos
Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Óperon/genética , RNA Mensageiro/química , RNA Mensageiro/fisiologia , Bactérias/classificação , Bactérias/genética , Códon de Terminação/metabolismo , Escherichia coli/metabolismo , Genes Bacterianos/genética , Iniciação Traducional da Cadeia Peptídica , Estrutura Secundária de Proteína , RNA Mensageiro/genética , Ribossomos/metabolismo
16.
mBio ; 11(5)2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913009

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), is a recently emerged respiratory coronavirus that has infected >23 million people worldwide with >800,000 deaths. Few COVID-19 therapeutics are available, and the basis for severe infections is poorly understood. Here, we investigated properties of type I (ß), II (γ), and III (λ1) interferons (IFNs), potent immune cytokines that are normally produced during infection and that upregulate IFN-stimulated gene (ISG) effectors to limit virus replication. IFNs are already in clinical trials to treat COVID-19. However, recent studies highlight the potential for IFNs to enhance expression of host angiotensin-converting enzyme 2 (ACE2), suggesting that IFN therapy or natural coinfections could exacerbate COVID-19 by upregulating this critical virus entry receptor. Using a cell line model, we found that beta interferon (IFN-ß) strongly upregulated expression of canonical antiviral ISGs, as well as ACE2 at the mRNA and cell surface protein levels. Strikingly, IFN-λ1 upregulated antiviral ISGs, but ACE2 mRNA was only marginally elevated and did not lead to detectably increased ACE2 protein at the cell surface. IFN-γ induced the weakest ISG response but clearly enhanced surface expression of ACE2. Importantly, all IFN types inhibited SARS-CoV-2 replication in a dose-dependent manner, and IFN-ß and IFN-λ1 exhibited potent antiviral activity in primary human bronchial epithelial cells. Our data imply that type-specific mechanisms or kinetics shape IFN-enhanced ACE2 transcript and cell surface levels but that the antiviral action of IFNs against SARS-CoV-2 counterbalances any proviral effects of ACE2 induction. These insights should aid in evaluating the benefits of specific IFNs, particularly IFN-λ, as repurposed therapeutics.IMPORTANCE Repurposing existing, clinically approved, antiviral drugs as COVID-19 therapeutics is a rapid way to help combat the SARS-CoV-2 pandemic. Interferons (IFNs) usually form part of the body's natural innate immune defenses against viruses, and they have been used with partial success to treat previous new viral threats, such as HIV, hepatitis C virus, and Ebola virus. Nevertheless, IFNs can have undesirable side effects, and recent reports indicate that IFNs upregulate the expression of host ACE2 (a critical entry receptor for SARS-CoV-2), raising the possibility that IFN treatments could exacerbate COVID-19. Here, we studied the antiviral- and ACE2-inducing properties of different IFN types in both a human lung cell line model and primary human bronchial epithelial cells. We observed differences between IFNs with respect to their induction of antiviral genes and abilities to enhance the cell surface expression of ACE2. Nevertheless, all the IFNs limited SARS-CoV-2 replication, suggesting that their antiviral actions can counterbalance increased ACE2.


Assuntos
Antivirais/farmacologia , Infecções por Coronavirus/tratamento farmacológico , Interferon Tipo I/farmacologia , Interferon gama/farmacologia , Interferons/farmacologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/tratamento farmacológico , Idoso , Animais , Betacoronavirus/imunologia , Linhagem Celular , Chlorocebus aethiops , Feminino , Humanos , Imunoterapia/métodos , Interferon Tipo I/efeitos adversos , Interferon gama/efeitos adversos , Interferons/efeitos adversos , Pandemias , Peptidil Dipeptidase A/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores Virais/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/virologia , Regulação para Cima/efeitos dos fármacos , Células Vero , Replicação Viral/efeitos dos fármacos
17.
Nat Commun ; 11(1): 4489, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895384

RESUMO

We report a covalent chemistry-based hepatocellular carcinoma (HCC)-specific extracellular vesicle (EV) purification system for early detection of HCC by performing digital scoring on the purified EVs. Earlier detection of HCC creates more opportunities for curative therapeutic interventions. EVs are present in circulation at relatively early stages of disease, providing potential opportunities for HCC early detection. We develop an HCC EV purification system (i.e., EV Click Chips) by synergistically integrating covalent chemistry-mediated EV capture/release, multimarker antibody cocktails, nanostructured substrates, and microfluidic chaotic mixers. We then explore the translational potential of EV Click Chips using 158 plasma samples of HCC patients and control cohorts. The purified HCC EVs are subjected to reverse-transcription droplet digital PCR for quantification of 10 HCC-specific mRNA markers and computation of digital scoring. The HCC EV-derived molecular signatures exhibit great potential for noninvasive early detection of HCC from at-risk cirrhotic patients with an area under receiver operator characteristic curve of 0.93 (95% CI, 0.86 to 1.00; sensitivity = 94.4%, specificity = 88.5%).


Assuntos
Biomarcadores Tumorais/isolamento & purificação , Carcinoma Hepatocelular/diagnóstico , Detecção Precoce de Câncer/métodos , Vesículas Extracelulares/genética , Neoplasias Hepáticas/diagnóstico , Idoso , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Química Click/instrumentação , Química Click/métodos , Química Computacional , Simulação por Computador , Diagnóstico Diferencial , Dimetilpolisiloxanos/química , Progressão da Doença , Detecção Precoce de Câncer/instrumentação , Feminino , Células Hep G2 , Humanos , Dispositivos Lab-On-A-Chip , Biópsia Líquida/instrumentação , Biópsia Líquida/métodos , Cirrose Hepática/sangue , Cirrose Hepática/patologia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Pessoa de Meia-Idade , Nanoestruturas/química , Nanofios/química , Estadiamento de Neoplasias , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Curva ROC , Reação em Cadeia da Polimerase Via Transcriptase Reversa/instrumentação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
18.
Pestic Biochem Physiol ; 170: 104703, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980071

RESUMO

For the last decade, scientists have reported a loss of honeybee colonies. Multiple factors like parasites, pathogens and pesticides are dealt as possible drivers of honeybee losses. In particular, insecticides are considered as a major factor of pollinator poisoning. We applied sublethal concentrations of four insecticidal substances to honeybee larval food and analyzed the effects on transcriptome. The aim was to identify candidate genes indicating early negative impacts after application of insecticidal substances. Honeybee larvae were kept in-vitro under hive conditions (34-35 °C) and fed with dimethoate, fenoxycarb, chlorantraniliprole and flupyradifurone in sublethal concentrations between day 3-6 after grafting. Larvae at day 4, 6 and 8 were sampled and their transcriptome analyzed. By use of a RT-qPCR array differences in gene expression of selected gene families (immune system, development detoxification) were measured. Targets mainly involved in development, energy metabolism and the immune system were significantly affected by the insecticidal substances tested, selectively inducing genes of the detoxification system, immune response and nutritional stress.


Assuntos
Inseticidas/farmacologia , Inseticidas/toxicidade , Animais , Abelhas/genética , Dimetoato , Larva/genética , RNA Mensageiro/genética , Transcriptoma
19.
Anticancer Res ; 40(9): 5091-5095, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878797

RESUMO

BACKGROUND/AIM: The purpose of the present study was to clarify whether treatment with YM155, a novel small-molecule inhibitor of survivin, reversed cabazitaxel resistance in castration-resistant prostate cancer (CRPC). MATERIALS AND METHODS: Cabazitaxel resistance was induced in the castration-resistant prostate cancer cell line, 22Rv1-CR. In vitro and in vivo models were used to test the efficacy of YM155 and cabazitaxel. RESULTS: Survivin gene expression was significantly higher in 22Rv1-CR than its parent cells (22Rv1). In 22Rv1-CR cells, YM155 significantly reduced expression of the survivin gene in a concentration-dependent manner. YM155 alone was poorly effective; however, it significantly enhanced the anticancer effects of cabazitaxel on 22Rv1-CR in vitro and in vivo. CONCLUSION: Inhibition of survivin by YM155 overcomes cabazitaxel resistance in CRPC cells.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Imidazóis/farmacologia , Naftoquinonas/farmacologia , Neoplasias de Próstata Resistentes à Castração/genética , Survivina/genética , Taxoides/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , RNA Mensageiro/genética , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Medicine (Baltimore) ; 99(30): e21331, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32791730

RESUMO

The aim of this study was to elucidate the possible association between migration inhibitory factor (MIF)-173G/C gene polymorphisms and transcript and plasma levels of MIF in spinal tuberculosis (TB) patients. Clinical data were collected from 254 spinal TB patients and 262 healthy controls participating in the study. The genotype of the MIF-173G/C gene was amplified by polymerase chain reaction and genotyped by DNA sequencing technology. The level of mRNA expression was determined by real-time polymerase chain reaction and MIF plasma levels were measured by a solid-phase enzyme-linked immunosorbent assay. The frequency of the C allele and GC+CC genotype in MIF-173G/C was over-represented in spinal TB patients. The mean MIF mRNA level in spinal TB patients and patients with the GG and GC+CC genotype were significantly lower than controls; however, our study also indicated that the MIF concentration in spinal TB patients and patients with the GG and GC+CC genotypes were significantly higher than controls. Spinal TB patients with the GG genotype had higher MIF plasma levels than patients with the GC+CC genotype. The C-reactive protein level and erythrocyte sedimentation rate was correlated with the MIF plasma level. In summary, the association between the MIF-173G/C genetic polymorphism, reduced transcript and increased plasma levels of MIF in spinal TB patients, and MIF may play an important role in the occurrence, development, and damage of spinal TB in the northern Province population of China.


Assuntos
Fatores Inibidores da Migração de Macrófagos/sangue , Polimorfismo Genético/genética , RNA Mensageiro/genética , Tuberculose da Coluna Vertebral/genética , Adulto , Alelos , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , China/epidemiologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Análise de Sequência de DNA/métodos
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