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1.
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
2.
PLoS Pathog ; 16(8): e1008792, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32813746

RESUMO

Tumor suppressors can exert pro-proliferation functions in specific contexts. In the beta human papillomavirus type 38 (HPV38) experimental model, the viral proteins E6 and E7 promote accumulation of a wild-type (WT) p53 form in human keratinocytes (HKs), promoting cellular proliferation. Inactivation of p53 by different means strongly decreases the proliferation of HPV38 E6/E7 HKs. This p53 form is phosphorylated at S392 by the double-stranded RNA-dependent protein kinase PKR, which is highly activated by HPV38. PKR-mediated S392 p53 phosphorylation promotes the formation of a p53/DNMT1 complex, which inhibits expression of integrin alpha 1 (ITGA1), a repressor of epidermal growth factor receptor (EGFR) signaling. Ectopic expression of ITGA1 in HPV38 E6/E7 HKs promotes EGFR degradation, inhibition of cellular proliferation, and cellular death. Itga1 expression was also inhibited in the skin of HPV38 transgenic mice that have an elevated susceptibility to UV-induced skin carcinogenesis. In summary, these findings reveal the existence of a specific WT p53 form that displays pro-proliferation properties.


Assuntos
Proteínas de Transporte/antagonistas & inibidores , Proliferação de Células , Queratinócitos/patologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/complicações , Proteínas Repressoras/metabolismo , Neoplasias Cutâneas/etiologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Células Cultivadas , Regulação para Baixo , Humanos , Queratinócitos/imunologia , Queratinócitos/virologia , Camundongos , Camundongos Transgênicos , Proteínas Oncogênicas Virais/genética , Papillomaviridae/isolamento & purificação , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/virologia , Proteínas Repressoras/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Proteína Supressora de Tumor p53/genética
3.
Nature ; 585(7824): 256-260, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32848244

RESUMO

Temperature controls plant growth and development, and climate change has already altered the phenology of wild plants and crops1. However, the mechanisms by which plants sense temperature are not well understood. The evening complex is a major signalling hub and a core component of the plant circadian clock2,3. The evening complex acts as a temperature-responsive transcriptional repressor, providing rhythmicity and temperature responsiveness to growth through unknown mechanisms2,4-6. The evening complex consists of EARLY FLOWERING 3 (ELF3)4,7, a large scaffold protein and key component of temperature sensing; ELF4, a small α-helical protein; and LUX ARRYTHMO (LUX), a DNA-binding protein required to recruit the evening complex to transcriptional targets. ELF3 contains a polyglutamine (polyQ) repeat8-10, embedded within a predicted prion domain (PrD). Here we find that the length of the polyQ repeat correlates with thermal responsiveness. We show that ELF3 proteins in plants from hotter climates, with no detectable PrD, are active at high temperatures, and lack thermal responsiveness. The temperature sensitivity of ELF3 is also modulated by the levels of ELF4, indicating that ELF4 can stabilize the function of ELF3. In both Arabidopsis and a heterologous system, ELF3 fused with green fluorescent protein forms speckles within minutes in response to higher temperatures, in a PrD-dependent manner. A purified fragment encompassing the ELF3 PrD reversibly forms liquid droplets in response to increasing temperatures in vitro, indicating that these properties reflect a direct biophysical response conferred by the PrD. The ability of temperature to rapidly shift ELF3 between active and inactive states via phase transition represents a previously unknown thermosensory mechanism.


Assuntos
Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas Priônicas/química , Temperatura , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Aclimatação/fisiologia , Arabidopsis/química , Temperatura Alta , Modelos Moleculares , Peptídeos/metabolismo , Transição de Fase , Domínios Proteicos , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo
4.
Nature ; 585(7824): 261-267, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32848246

RESUMO

Sustained, drug-free control of HIV-1 replication is naturally achieved in less than 0.5% of infected individuals (here termed 'elite controllers'), despite the presence of a replication-competent viral reservoir1. Inducing such an ability to spontaneously maintain undetectable plasma viraemia is a major objective of HIV-1 cure research, but the characteristics of proviral reservoirs in elite controllers remain to be determined. Here, using next-generation sequencing of near-full-length single HIV-1 genomes and corresponding chromosomal integration sites, we show that the proviral reservoirs of elite controllers frequently consist of oligoclonal to near-monoclonal clusters of intact proviral sequences. In contrast to individuals treated with long-term antiretroviral therapy, intact proviral sequences from elite controllers were integrated at highly distinct sites in the human genome and were preferentially located in centromeric satellite DNA or in Krüppel-associated box domain-containing zinc finger genes on chromosome 19, both of which are associated with heterochromatin features. Moreover, the integration sites of intact proviral sequences from elite controllers showed an increased distance to transcriptional start sites and accessible chromatin of the host genome and were enriched in repressive chromatin marks. These data suggest that a distinct configuration of the proviral reservoir represents a structural correlate of natural viral control, and that the quality, rather than the quantity, of viral reservoirs can be an important distinguishing feature for a functional cure of HIV-1 infection. Moreover, in one elite controller, we were unable to detect intact proviral sequences despite analysing more than 1.5 billion peripheral blood mononuclear cells, which raises the possibility that a sterilizing cure of HIV-1 infection, which has previously been observed only following allogeneic haematopoietic stem cell transplantation2,3, may be feasible in rare instances.


Assuntos
Inativação Gênica , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/genética , Heterocromatina/genética , Provírus/genética , Integração Viral/genética , Latência Viral/genética , Adulto , Idoso , Centrômero/genética , Cromossomos Humanos Par 19/genética , DNA Satélite/genética , Feminino , Genoma Viral/genética , Infecções por HIV/sangue , HIV-1/isolamento & purificação , Heterocromatina/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Provírus/isolamento & purificação , Proteínas Repressoras/genética , Sítio de Iniciação de Transcrição
5.
Nature ; 584(7820): 286-290, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760002

RESUMO

The histone deacetylases (HDACs) are a superfamily of chromatin-modifying enzymes that silence transcription through the modification of histones. Among them, HDAC3 is unique in that interaction with nuclear receptor corepressors 1 and 2 (NCoR1/2) is required to engage its catalytic activity1-3. However, global loss of HDAC3 also results in the repression of transcription, the mechanism of which is currently unclear4-8. Here we report that, during the activation of macrophages by lipopolysaccharides, HDAC3 is recruited to activating transcription factor 2 (ATF2)-bound sites without NCoR1/2 and activates the expression of inflammatory genes through a non-canonical mechanism. By contrast, the deacetylase activity of HDAC3 is selectively engaged at ATF3-bound sites that suppress Toll-like receptor signalling. Loss of HDAC3 in macrophages safeguards mice from lethal exposure to lipopolysaccharides, but this protection is not conferred upon genetic or pharmacological abolition of the catalytic activity of HDAC3. Our findings show that HDAC3 is a dichotomous transcriptional activator and repressor, with a non-canonical deacetylase-independent function that is vital for the innate immune system.


Assuntos
Histona Desacetilases/metabolismo , Inflamação/genética , Inflamação/metabolismo , Fator 2 Ativador da Transcrição/metabolismo , Fator 3 Ativador da Transcrição/metabolismo , Animais , Biocatálise , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/genética , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Masculino , Camundongos , Correpressor 1 de Receptor Nuclear , Correpressor 2 de Receptor Nuclear , Proteínas Repressoras/metabolismo , Transcrição Genética/efeitos dos fármacos
6.
Methods Mol Biol ; 2203: 187-204, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32833213

RESUMO

Biotin-based proximity labeling circumvents major pitfalls of classical biochemical approaches to identify protein-protein interactions. It consists of enzyme-catalyzed biotin tags ubiquitously apposed on proteins located in close proximity of the labeling enzyme, followed by affinity purification and identification of biotinylated proteins by mass spectrometry. Here we outline the methods by which the molecular microenvironment of the coronavirus replicase/transcriptase complex (RTC), i.e., proteins located within a close perimeter of the RTC, can be determined by different proximity labeling approaches using BirAR118G (BioID), TurboID, and APEX2. These factors represent a molecular signature of coronavirus RTCs and likely contribute to the viral life cycle, thereby constituting attractive targets for the development of antiviral intervention strategies.


Assuntos
Coronavirus/patogenicidade , Enzimas/genética , Interações Hospedeiro-Patógeno/fisiologia , Proteômica/métodos , Proteínas Virais/metabolismo , Animais , Ascorbato Peroxidases/genética , Biotinilação , Carbono-Nitrogênio Ligases/genética , Linhagem Celular , Coronavirus/genética , Enzimas/metabolismo , Proteínas de Escherichia coli/genética , Imunofluorescência , Microrganismos Geneticamente Modificados , Proteínas Repressoras/genética , Proteínas Virais/química , Proteínas Virais/genética
7.
Nat Commun ; 11(1): 3841, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737323

RESUMO

Histone deacetylases (HDACs) are key enzymes in epigenetics and important drug targets in cancer biology. Whilst it has been established that HDACs regulate many cellular processes, far less is known about the regulation of these enzymes themselves. Here, we show that HDAC8 is allosterically regulated by shifts in populations between exchanging states. An inactive state is identified, which is stabilised by a range of mutations and resembles a sparsely-populated state in equilibrium with active HDAC8. Computational models show that the inactive and active states differ by small changes in a regulatory region that extends up to 28 Å from the active site. The regulatory allosteric region identified here in HDAC8 corresponds to regions in other class I HDACs known to bind regulators, thus suggesting a general mechanism. The presented results pave the way for the development of allosteric HDAC inhibitors and regulators to improve the therapy for several disease states.


Assuntos
Inibidores de Histona Desacetilases/química , Histona Desacetilases/química , Ácidos Hidroxâmicos/química , Indóis/química , Proteínas Repressoras/química , Vorinostat/química , Regulação Alostérica , Sítio Alostérico , Domínio Catalítico , Clonagem Molecular , Cristalografia por Raios X , Ativação Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Inibidores de Histona Desacetilases/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/metabolismo , Indóis/metabolismo , Simulação de Dinâmica Molecular , Mutação , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Especificidade por Substrato , Termodinâmica , Vorinostat/metabolismo
8.
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
9.
PLoS One ; 15(7): e0235922, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32673370

RESUMO

We have previously established that epigenetic regulator RING1 and YY1 binding protein (RYBP) is required for the contractility of embryonic stem (ES) cell derived cardiomyocytes (CMCs), suggesting its essential role in contractility. In order to investigate the underlying molecular events of this phenotype, we compared the transcriptomic profile of the wild type and Rybp null mutant ES cells and CMCs differentiated from these cell lines. We identified genes related to ion homeostasis, cell adhesion and sarcomeric organization affected in the Rybp null mutant CMCs, by using hierarchical gene clustering and Gene Ontology analysis. We have also demonstrated that the amount of RYBP is drastically reduced in the terminally differentiated wild type CMCs whilst it is broadly expressed in the early phase of differentiation when progenitors form. We also describe that RYBP is important for the proper expression of key cardiac transcription factors including Mesp1, Shh and Mef2c. These findings identify Rybp as a gene important for both early cardiac gene transcription and consequent sarcomere formation necessary for contractility. Since impairment of sarcomeric function and contractility plays a central role in reduced cardiac pump function leading to heart failures in human, current results might be relevant to the pathophysiology of cardiomyopathies.


Assuntos
Proteínas Repressoras/genética , Sarcômeros/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Diferenciação Celular , Linhagem Celular , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , RNA Mensageiro/metabolismo , Proteínas Repressoras/deficiência
10.
Int J Oral Sci ; 12(1): 20, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32606293

RESUMO

As a member of the AFF (AF4/FMR2) family, AFF4 is a transcription elongation factor that is a component of the super elongation complex. AFF4 serves as a scaffolding protein that connects transcription factors and promotes gene transcription through elongation and chromatin remodelling. Here, we investigated the effect of AFF4 on human dental follicle cells (DFCs) in osteogenic differentiation. In this study, we found that small interfering RNA-mediated depletion of AFF4 resulted in decreased alkaline phosphatase (ALP) activity and impaired mineralization. In addition, the expression of osteogenic-related genes (DLX5, SP7, RUNX2 and BGLAP) was significantly downregulated. In contrast, lentivirus-mediated overexpression of AFF4 significantly enhanced the osteogenic potential of human DFCs. Mechanistically, we found that both the mRNA and protein levels of ALKBH1, a critical regulator of epigenetics, changed in accordance with AFF4 expression levels. Overexpression of ALKBH1 in AFF4-depleted DFCs partially rescued the impairment of osteogenic differentiation. Our data indicated that AFF4 promoted the osteogenic differentiation of DFCs by upregulating the transcription of ALKBH1.


Assuntos
Saco Dentário/metabolismo , Osteogênese/genética , Fatores de Transcrição/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular , Células Cultivadas , Saco Dentário/efeitos dos fármacos , Regulação da Expressão Gênica , Humanos , Proteínas Repressoras , Fatores de Transcrição/genética
11.
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
12.
Life Sci ; 257: 118021, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32621919

RESUMO

AIMS: Tribbles homolog 3 (TRIB3) is emerging as a multifunctional oncoprotein associated with various cellular events in different tumors. However, the regulatory mechanism of TRIB3 in acute myeloid leukemia (AML) remains unknown. This study aims to investigate the molecular mechanisms and uncover the functions of TRIB3 in AML. METHODS: Western blotting and quantitative real-time PCR were used to analyze the expression levels of TRIB3, peroxisome proliferator-activated receptor α (PPARα), apoptosis markers and autophagy markers in AML cells. Flow cytometry was used to assess cell apoptosis. The interaction of TRIB3 and PPARα was evaluated by immunofluorescence, coimmunoprecipitation, and in vivo ubiquitination assays. KEY FINDINGS: We demonstrated that downregulating TRIB3 in leukemic cells effectively induced apoptosis and autophagy by regulating the degradation of PPARα. Mechanistically, TRIB3 interacted with PPARα and contributed to its destabilization by promoting its ubiquitination. When PPARα was activated by its specific agonist clofibrate, the apoptosis and autophagy of AML cells were significantly enhanced. These results were confirmed by rescue experiments. Blocking PPARα expression using the PPARα inhibitor GW6471 reversed the functional influence of TRIB3 on AML cells. SIGNIFICANCE: The aim of this study is to provide evidence of the degradation of PPARα by TRIB3 via ubiquitin-dependent proteasomal degradation. This process meditates the progression of AML and prolongs the survival of leukemic cells. As a result, these data indicate that TRIB3 is a novel and promising therapeutic target for AML treatment.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Leucemia Mieloide Aguda/genética , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Apoptose/fisiologia , Autofagia/fisiologia , Bases de Dados Genéticas , Humanos , Leucemia Mieloide Aguda/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteostase/fisiologia , Transdução de Sinais/fisiologia , Ubiquitina/metabolismo , Ubiquitinação
13.
Nat Commun ; 11(1): 3660, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32694521

RESUMO

High expression or aberrant activation of epidermal growth factor receptor (EGFR) is related to tumor progression and therapy resistance across cancer types, including non-small cell lung cancer (NSCLC). EGFR tyrosine kinase inhibitors (TKIs) are first-line therapy for NSCLC. However, patients eventually deteriorate after inevitable acquisition of EGFR TKI-resistant mutations, highlighting the need for therapeutics with alternative mechanisms of action. Here, we report that the elevated tribbles pseudokinase 3 (TRIB3) is positively associated with EGFR stability and NSCLC progression. TRIB3 interacts with EGFR and recruits PKCα to induce a Thr654 phosphorylation and WWP1-induced Lys689 ubiquitination in the EGFR juxtamembrane region, which enhances EGFR recycling, stability, downstream activity, and NSCLC stemness. Disturbing the TRIB3-EGFR interaction with a stapled peptide attenuates NSCLC progression by accelerating EGFR degradation and sensitizes NSCLC cells to chemotherapeutic agents. These findings indicate that targeting EGFR degradation is a previously unappreciated therapeutic option in EGFR-related NSCLC.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Ciclo Celular/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Adulto , Animais , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Linhagem Celular Tumoral , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação , Fosforilação/efeitos dos fármacos , Proteína Quinase C-alfa/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteólise/efeitos dos fármacos , Taxa de Sobrevida , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Proc Natl Acad Sci U S A ; 117(29): 17228-17239, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32616573

RESUMO

The ability of Staphylococcus aureus to infect many different tissue sites is enabled, in part, by its transcriptional regulatory network (TRN) that coordinates its gene expression to respond to different environments. We elucidated the organization and activity of this TRN by applying independent component analysis to a compendium of 108 RNA-sequencing expression profiles from two S. aureus clinical strains (TCH1516 and LAC). ICA decomposed the S. aureus transcriptome into 29 independently modulated sets of genes (i-modulons) that revealed: 1) High confidence associations between 21 i-modulons and known regulators; 2) an association between an i-modulon and σS, whose regulatory role was previously undefined; 3) the regulatory organization of 65 virulence factors in the form of three i-modulons associated with AgrR, SaeR, and Vim-3; 4) the roles of three key transcription factors (CodY, Fur, and CcpA) in coordinating the metabolic and regulatory networks; and 5) a low-dimensional representation, involving the function of few transcription factors of changes in gene expression between two laboratory media (RPMI, cation adjust Mueller Hinton broth) and two physiological media (blood and serum). This representation of the TRN covers 842 genes representing 76% of the variance in gene expression that provides a quantitative reconstruction of transcriptional modules in S. aureus, and a platform enabling its full elucidation.


Assuntos
Regulação Bacteriana da Expressão Gênica , Redes Reguladoras de Genes/genética , Staphylococcus aureus/genética , Staphylococcus aureus/fisiologia , Transcriptoma , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Redes e Vias Metabólicas , Proteínas Repressoras/genética , Análise de Sequência de RNA , Fator sigma/genética , Infecções Estafilocócicas , Virulência/genética , Fatores de Virulência/genética
15.
Nat Commun ; 11(1): 3398, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32636384

RESUMO

SWI/SNF remodelers play a key role in regulating chromatin architecture and gene expression. Here, we report the cryo-EM structure of the Saccharomyces cerevisiae Swi/Snf complex in a nucleosome-free state. The structure consists of a stable triangular base module and a flexible Arp module. The conserved subunits Swi1 and Swi3 form the backbone of the complex and closely interact with other components. Snf6, which is specific for yeast Swi/Snf complex, stabilizes the binding of the ATPase-containing subunit Snf2 to the base module. Comparison of the yeast Swi/Snf and RSC complexes reveals conserved structural features that govern the assembly and function of these two subfamilies of chromatin remodelers. Our findings complement those from recent structures of the yeast and human chromatin remodelers and provide further insights into the assembly and function of the SWI/SNF remodelers.


Assuntos
Adenosina Trifosfatases/química , Cromatina/química , Proteínas Cromossômicas não Histona/química , Proteínas Nucleares/química , Proteínas Repressoras/química , Proteínas de Saccharomyces cerevisiae/química , Fatores de Transcrição/química , Microscopia Crioeletrônica , Proteínas de Ligação a DNA/química , Humanos , Nucleossomos , Ligação Proteica , Domínios Proteicos , Saccharomyces cerevisiae/química
16.
PLoS Genet ; 16(7): e1008908, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32639995

RESUMO

The human fungal pathogen Candida albicans is constantly exposed to environmental challenges impacting the cell wall. Signaling pathways coordinate stress adaptation and are essential for commensalism and virulence. The transcription factors Sko1, Cas5, and Rlm1 control the response to cell wall stress caused by the antifungal drug caspofungin. Here, we expand the Sko1 and Rlm1 transcriptional circuit and demonstrate that Rlm1 activates Sko1 cell wall stress signaling. Caspofungin-induced transcription of SKO1 and several Sko1-dependent cell wall integrity genes are attenuated in an rlm1Δ/Δ mutant strain when compared to the treated wild-type strain but not in a cas5Δ/Δ mutant strain. Genome-wide chromatin immunoprecipitation (ChIP-seq) results revealed numerous Sko1 and Rlm1 directly bound target genes in the presence of caspofungin that were undetected in previous gene expression studies. Notable targets include genes involved in cell wall integrity, osmolarity, and cellular aggregation, as well as several uncharacterized genes. Interestingly, we found that Rlm1 does not bind to the upstream intergenic region of SKO1 in the presence of caspofungin, indicating that Rlm1 indirectly controls caspofungin-induced SKO1 transcription. In addition, we discovered that caspofungin-induced SKO1 transcription occurs through self-activation. Based on our ChIP-seq data, we also discovered an Rlm1 consensus motif unique to C. albicans. For Sko1, we found a consensus motif similar to the known Sko1 motif for Saccharomyces cerevisiae. Growth assays showed that SKO1 overexpression suppressed caspofungin hypersensitivity in an rlm1Δ/Δ mutant strain. In addition, overexpression of the glycerol phosphatase, RHR2, suppressed caspofungin hypersensitivity specifically in a sko1Δ/Δ mutant strain. Our findings link the Sko1 and Rlm1 signaling pathways, identify new biological roles for Sko1 and Rlm1, and highlight the complex dynamics underlying cell wall signaling.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Candida albicans/efeitos dos fármacos , Caspofungina/farmacologia , Proteínas de Domínio MADS/genética , Proteínas Repressoras/genética , Proteínas de Saccharomyces cerevisiae/genética , Antifúngicos/farmacologia , Candida albicans/genética , Candida albicans/patogenicidade , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Humanos , Fosforilação/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética
17.
Nature ; 584(7819): 142-147, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32612238

RESUMO

Nuclear processes, such as V(D)J recombination, are orchestrated by the three-dimensional organization of chromosomes at multiple levels, including compartments1 and topologically associated domains (TADs)2,3 consisting of chromatin loops4. TADs are formed by chromatin-loop extrusion5-7, which depends on the loop-extrusion function of the ring-shaped cohesin complex8-12. Conversely, the cohesin-release factor Wapl13,14 restricts loop extension10,15. The generation of a diverse antibody repertoire, providing humoral immunity to pathogens, requires the participation of all V genes in V(D)J recombination16, which depends on contraction of the 2.8-Mb-long immunoglobulin heavy chain (Igh) locus by Pax517,18. However, how Pax5 controls Igh contraction in pro-B cells remains unknown. Here we demonstrate that locus contraction is caused by loop extrusion across the entire Igh locus. Notably, the expression of Wapl is repressed by Pax5 specifically in pro-B and pre-B cells, facilitating extended loop extrusion by increasing the residence time of cohesin on chromatin. Pax5 mediates the transcriptional repression of Wapl through a single Pax5-binding site by recruiting the polycomb repressive complex 2 to induce bivalent chromatin at the Wapl promoter. Reduced Wapl expression causes global alterations in the chromosome architecture, indicating that the potential to recombine all V genes entails structural changes of the entire genome in pro-B cells.


Assuntos
Genes de Cadeia Pesada de Imunoglobulina/genética , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Fator de Transcrição PAX5/metabolismo , Proteínas/genética , Proteínas Repressoras/metabolismo , Recombinação V(D)J/genética , Animais , Linfócitos B/citologia , Linfócitos B/metabolismo , Sítios de Ligação , Proteínas de Ciclo Celular/metabolismo , Montagem e Desmontagem da Cromatina , Proteínas Cromossômicas não Histona/metabolismo , Cadeias Pesadas de Imunoglobulinas/química , Região Variável de Imunoglobulina/química , Camundongos , Complexo Repressor Polycomb 2/metabolismo , Células Precursoras de Linfócitos B/citologia , Células Precursoras de Linfócitos B/metabolismo , Regiões Promotoras Genéticas/genética
18.
Rev Cardiovasc Med ; 21(2): 253-261, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32706213

RESUMO

It is known that functional defects of GATA binding protein 5 (GATA5), an important member of GATA transcription factor family, could cause multiple congenital defects. However, the mechanisms of this transcription factor in cardiovascular diseases are still little known. Finding a genetic approach should help with understanding the possible roles of GATA5 in different cardiovascular diseases and purpose it as a possible therapeutic agent. Hence, this review is divided into three chapters to summarize the roles and main regulatory mechanisms of GATA5 in hypertension, arrhythmia and congenital heart disease, respectively. In each chapter, this review firstly introduces the roles of GATA5 mutations, and then discusses the main regulatory mechanisms of GATA5 in the corresponding diseases (Such as the endothelial dysfunction signaling pathway in the chapter of hypertension, GATA5-NaV1.5 signaling pathway in the chapter of arrhythmia, GATA5-HEY2 and GATA5-Nodal signaling pathway in the chapter of congenital heart disease). Additionally, based on these regulatory networks, it is also speculated that abnormal methylation of the GATA5 gene promoter may lead to cardiovascular diseases such as congenital heart disease. This conjecture is proposed to enrich the regulatory networks of GATA5 and provide a theoretical basis for diagnosis and treatment of cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/metabolismo , Sistema Cardiovascular/metabolismo , Fator de Transcrição GATA5/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/fisiopatologia , Sistema Cardiovascular/fisiopatologia , Fator de Transcrição GATA5/genética , Redes Reguladoras de Genes , Predisposição Genética para Doença , Humanos , Mutação , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais
19.
Bratisl Lek Listy ; 121(8): 584-588, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726122

RESUMO

AIM: Investigate how AT1/2R affected the proliferation and apoptosis of chondrocytes induced by oxygen-glucose deprivation. METHODS: The proliferation and apoptosis of ATDC5 cells was detected by CCK-8 assay and flow cytometry analysis. The expression of Bax, Bcl-2, caspase-3, cleaved-caspase-3, AT1R, AT2R and HIF-1 was determined by Western blot analysis. The collagen II expression was detected by ELISA assay. RESULTS: Increased ratio of AT1R to AT2R induced by Ang II suppressed the proliferation of oxygen-glucose deprivation ATDC5 cells. Telmisartan, as AT1R inhibitor, promoted the proliferation and inhibited the apoptosis of ATDC5 cells and oxygen-glucose deprivation ATDC5 cells. The collagen II expression either intracellular or cellular supernatant was decreased after Ang II treatment, which was reversed by telmisartan. And, telmisartan reduced the AT1R expression while increased the AT2R expression in ATDC5 cells and oxygen-glucose deprivation ATDC5 cells. CONCLUSIONS: Ang II caused an increased ratio of AT1R to AT2R, which suppressed the proliferation of oxygen-glucose deprivation ATDC5 cells. Furthermore, telmisartan caused a decrease of AT1R and increase of AT2R, which promoted the proliferation and inhibited the apoptosis of oxygen-glucose deprivation ATDC5 cells. This new finding could provide a new insight into the treatment of osteoarthritis (Fig. 4, Ref. 19).


Assuntos
Apoptose , Condrócitos , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Angiotensina II , Animais , Proliferação de Células , Glucose , Camundongos , Proteínas do Tecido Nervoso , Oxigênio , Proteínas Repressoras
20.
Molecules ; 25(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604797

RESUMO

Viruses can be spread from one person to another; therefore, they may cause disorders in many people, sometimes leading to epidemics and even pandemics. New, previously unstudied viruses and some specific mutant or recombinant variants of known viruses constantly appear. An example is a variant of coronaviruses (CoV) causing severe acute respiratory syndrome (SARS), named SARS-CoV-2. Some antiviral drugs, such as remdesivir as well as antiretroviral drugs including darunavir, lopinavir, and ritonavir are suggested to be effective in treating disorders caused by SARS-CoV-2. There are data on the utilization of antiretroviral drugs against SARS-CoV-2. Since there are many studies aimed at the identification of the molecular mechanisms of human immunodeficiency virus type 1 (HIV-1) infection and the development of novel therapeutic approaches against HIV-1, we used HIV-1 for our case study to identify possible molecular pathways shared by SARS-CoV-2 and HIV-1. We applied a text and data mining workflow and identified a list of 46 targets, which can be essential for the development of infections caused by SARS-CoV-2 and HIV-1. We show that SARS-CoV-2 and HIV-1 share some molecular pathways involved in inflammation, immune response, cell cycle regulation.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/metabolismo , Mineração de Dados/métodos , Infecções por HIV/epidemiologia , Infecções por HIV/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/metabolismo , Anti-Inflamatórios/uso terapêutico , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/imunologia , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Proteínas do Sistema Complemento/genética , Proteínas do Sistema Complemento/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Bases de Dados Genéticas , Regulação da Expressão Gênica , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/efeitos dos fármacos , HIV-1/imunologia , HIV-1/patogenicidade , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Humanos , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/uso terapêutico , Inflamação , Interferons/genética , Interferons/imunologia , Interleucinas/genética , Interleucinas/imunologia , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Redes e Vias Metabólicas/imunologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Proteínas Repressoras/genética , Proteínas Repressoras/imunologia , Transdução de Sinais , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/imunologia
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