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1.
Nat Commun ; 11(1): 4561, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917873

RESUMO

The protein high-mobility group box 1 (HMGB1) is released into the extracellular space in response to many inflammatory stimuli, where it is a potent signaling molecule. Although research has focused on downstream HMGB1 signaling, the means by which HMGB1 exits the cell is controversial. Here we demonstrate that HMGB1 is not released from bone marrow-derived macrophages (BMDM) after lipopolysaccharide (LPS) treatment. We also explore whether HMGB1 is released via the pore-forming protein gasdermin D after inflammasome activation, as is the case for IL-1ß. HMGB1 is only released under conditions that cause cell lysis (pyroptosis). When pyroptosis is prevented, HMGB1 is not released, despite inflammasome activation and IL-1ß secretion. During endotoxemia, gasdermin D knockout mice secrete HMGB1 normally, yet secretion of IL-1ß is completely blocked. Together, these data demonstrate that in vitro HMGB1 release after inflammasome activation occurs after cellular rupture, which is probably inflammasome-independent in vivo.


Assuntos
Proteína HMGB1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Animais , Modelos Animais de Doenças , Endotoxemia/metabolismo , Feminino , Proteína HMGB1/genética , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipopolissacarídeos/efeitos adversos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Ligação a Fosfato/genética , Piroptose , Transdução de Sinais
2.
Nat Commun ; 11(1): 4875, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978388

RESUMO

Single-cell whole-exome sequencing (scWES) is a powerful approach for deciphering intratumor heterogeneity and identifying cancer drivers. So far, however, simultaneous analysis of single nucleotide variants (SNVs) and copy number variations (CNVs) of a single cell has been challenging. By analyzing SNVs and CNVs simultaneously in bulk and single cells of premalignant tissues and tumors from mouse and human BRCA1-associated breast cancers, we discover an evolution process through which the tumors initiate from cells with SNVs affecting driver genes in the premalignant stage and malignantly progress later via CNVs acquired in chromosome regions with cancer driver genes. These events occur randomly and hit many putative cancer drivers besides p53 to generate unique genetic and pathological features for each tumor. Upon this, we finally identify a tumor metastasis suppressor Plekha5, whose deficiency promotes cancer metastasis to the liver and/or lung.


Assuntos
Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Predisposição Genética para Doença/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lesões Pré-Cancerosas/genética , Animais , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Modelos Animais de Doenças , Heterogeneidade Genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fígado/patologia , Pulmão/patologia , Camundongos , Camundongos Knockout , Mutação , Lesões Pré-Cancerosas/patologia , Transcriptoma
3.
Nat Commun ; 11(1): 4150, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811819

RESUMO

The systemic decline in autophagic activity with age impairs homeostasis in several tissues, leading to age-related diseases. A mechanistic understanding of adipocyte dysfunction with age could help to prevent age-related metabolic disorders, but the role of autophagy in aged adipocytes remains unclear. Here we show that, in contrast to other tissues, aged adipocytes upregulate autophagy due to a decline in the levels of Rubicon, a negative regulator of autophagy. Rubicon knockout in adipocytes causes fat atrophy and hepatic lipid accumulation due to reductions in the expression of adipogenic genes, which can be recovered by activation of PPARγ. SRC-1 and TIF2, coactivators of PPARγ, are degraded by autophagy in a manner that depends on their binding to GABARAP family proteins, and are significantly downregulated in Rubicon-ablated or aged adipocytes. Hence, we propose that age-dependent decline in adipose Rubicon exacerbates metabolic disorders by promoting excess autophagic degradation of SRC-1 and TIF2.


Assuntos
Adipócitos/metabolismo , Envelhecimento/fisiologia , Autofagia/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Doenças Metabólicas/metabolismo , Adipócitos/patologia , Adipogenia/genética , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Adiposidade/genética , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/fisiologia , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Técnicas de Inativação de Genes , Glucose/genética , Glucose/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Metabolismo dos Lipídeos/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Coativador 1 de Receptor Nuclear/metabolismo , Coativador 2 de Receptor Nuclear/metabolismo , PPAR gama/metabolismo
4.
Nat Commun ; 11(1): 4154, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32814778

RESUMO

The DNA damage response (DDR) coordinates DNA metabolism with nuclear and non-nuclear processes. The DDR kinase Rad53CHK1/CHK2 controls histone degradation to assist DNA repair. However, Rad53 deficiency causes histone-dependent growth defects in the absence of DNA damage, pointing out unknown physiological functions of the Rad53-histone axis. Here we show that histone dosage control by Rad53 ensures metabolic homeostasis. Under physiological conditions, Rad53 regulates histone levels through inhibitory phosphorylation of the transcription factor Spt21NPAT on Ser276. Rad53-Spt21 mutants display severe glucose dependence, caused by excess histones through two separable mechanisms: dampening of acetyl-coenzyme A-dependent carbon metabolism through histone hyper-acetylation, and Sirtuin-mediated silencing of starvation-induced subtelomeric domains. We further demonstrate that repression of subtelomere silencing by physiological Tel1ATM and Rpd3HDAC activities coveys tolerance to glucose restriction. Our findings identify DDR mutations, histone imbalances and aberrant subtelomeric chromatin as interconnected causes of glucose dependence, implying that DDR kinases coordinate metabolism and epigenetic changes.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Quinase do Ponto de Checagem 2/metabolismo , Glucose/metabolismo , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Ciclo Celular/genética , Quinase do Ponto de Checagem 2/genética , Dano ao DNA , Reparo do DNA , Inativação Gênica , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mutação , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Serina/genética , Serina/metabolismo , Telômero/genética , Fatores de Transcrição/genética
5.
Chem Biol Interact ; 330: 109232, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32860822

RESUMO

Currently, whether nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation contributes to neuropathy induced by 2,5-Hexanedione (HD), the toxic metabolite of n-hexane, remains unknown. In this study, we found that HD intoxication elevated NLRP3 expression, caspase-1 activation and interleukin-1ß production in sciatic nerve of rats, indicating activation of NLRP3 inflammasome. The increased cleavage of gasdermin D (GSDMD) protein, an important mediator of pyroptosis, and axon degeneration were also observed in sciatic nerves of HD-intoxicated rats. Interestingly, glybenclamide, a widely used inhibitor of NLRP3 inflammasome, significantly reduced NLRP3 inflammasome activation, which was associated with decreased GSDMD cleavage and axon degeneration as well as improved motor performance of HD-intoxicated rats. Subsequently, we found that inhibition of NLRP3 inflammasome by glybenclamide attenuated macrophage infiltration, activation and M1 polarization in sciatic nerves of HD-intoxicated rats. Furthermore, decreased malondialdehyde (MDA) contents and increased glutathione (GSH) level and total anti-oxidative capacity were also observed in sciatic nerves of rats treated with combined glybenclamide and HD compared with HD alone group. Altogether, our findings suggest that NLRP3 inflammasome activation contributes to HD-induced neurotoxicity by enhancing macrophage infiltration and activation as well as oxidative stress, providing a novel mechanism of neuropathy induced by this neurotoxicant.


Assuntos
Hexanonas/toxicidade , Macrófagos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/farmacologia , Síndromes Neurotóxicas/etiologia , Animais , Antioxidantes/metabolismo , Movimento Celular/efeitos dos fármacos , Glutationa/metabolismo , Glibureto/farmacologia , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Síndromes Neurotóxicas/tratamento farmacológico , Estresse Oxidativo , Proteínas de Ligação a Fosfato/metabolismo , Piroptose , Ratos , Nervo Isquiático/metabolismo , Nervo Isquiático/patologia
6.
J Biol Chem ; 295(41): 14040-14052, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32763970

RESUMO

Coronaviruses have caused several zoonotic infections in the past two decades, leading to significant morbidity and mortality globally. Balanced regulation of cell death and inflammatory immune responses is essential to promote protection against coronavirus infection; however, the underlying mechanisms that control these processes remain to be resolved. Here we demonstrate that infection with the murine coronavirus mouse hepatitis virus (MHV) activated the NLRP3 inflammasome and inflammatory cell death in the form of PANoptosis. Deleting NLRP3 inflammasome components or the downstream cell death executioner gasdermin D (GSDMD) led to an initial reduction in cell death followed by a robust increase in the incidence of caspase-8- and receptor-interacting serine/threonine-protein kinase 3 (RIPK3)-mediated inflammatory cell deathafter coronavirus infection. Additionally, loss of GSDMD promoted robust NLRP3 inflammasome activation. Moreover, the amounts of some cytokines released during coronavirus infection were significantly altered in the absence of GSDMD. Altogether, our findings show that inflammatory cell death, PANoptosis, is induced by coronavirus infection and that impaired NLRP3 inflammasome function or pyroptosis can lead to negative consequences for the host. These findings may have important implications for studies of coronavirus-induced disease.


Assuntos
Caspase 8/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Células Cultivadas , Coronavirus/fisiologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/patologia , Infecções por Coronavirus/veterinária , Citocinas/metabolismo , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Necroptose , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/metabolismo
7.
Proc Natl Acad Sci U S A ; 117(35): 21319-21327, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817489

RESUMO

Organisms can adapt to a broad spectrum of sudden and dramatic changes in their environment. These abrupt changes are often perceived as stress and trigger responses that facilitate survival and eventual adaptation. The ubiquitin-proteasome system (UPS) is involved in most cellular processes. Unsurprisingly, components of the UPS also play crucial roles during various stress response programs. The budding yeast SCFMet30 complex is an essential cullin-RING ubiquitin ligase that connects metabolic and heavy metal stress to cell cycle regulation. Cadmium exposure results in the active dissociation of the F-box protein Met30 from the core ligase, leading to SCFMet30 inactivation. Consequently, SCFMet30 substrate ubiquitylation is blocked and triggers a downstream cascade to activate a specific transcriptional stress response program. Signal-induced dissociation is initiated by autoubiquitylation of Met30 and serves as a recruitment signal for the AAA-ATPase Cdc48/p97, which actively disassembles the complex. Here we show that the UBX cofactor Shp1/p47 is an additional key element for SCFMet30 disassembly during heavy metal stress. Although the cofactor can directly interact with the ATPase, Cdc48 and Shp1 are recruited independently to SCFMet30 during cadmium stress. An intact UBX domain is crucial for effective SCFMet30 disassembly, and a concentration threshold of Shp1 recruited to SCFMet30 needs to be exceeded to initiate Met30 dissociation. The latter is likely related to Shp1-mediated control of Cdc48 ATPase activity. This study identifies Shp1 as the crucial Cdc48 cofactor for signal-induced selective disassembly of a multisubunit protein complex to modulate activity.


Assuntos
Proteínas F-Box/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo , Proteína com Valosina/metabolismo , Cádmio , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mutação , Domínios Proteicos , Multimerização Proteica , Proteínas de Saccharomyces cerevisiae/genética , Saccharomycetales , Estresse Fisiológico
8.
Proc Natl Acad Sci U S A ; 117(35): 21354-21363, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817543

RESUMO

One of the hallmarks of DNA damage is the rapid spreading of phosphorylated histone H2A (γ-H2AX) around a DNA double-strand break (DSB). In the budding yeast Saccharomyces cerevisiae, nearly all H2A isoforms can be phosphorylated, either by Mec1ATR or Tel1ATM checkpoint kinases. We induced a site-specific DSB with HO endonuclease at the MAT locus on chromosome III and monitored the formation of γ-H2AX by chromatin immunoprecipitation (ChIP)-qPCR in order to uncover the mechanisms by which Mec1ATR and Tel1ATM propagate histone modifications across chromatin. With either kinase, γ-H2AX spreads as far as ∼50 kb on both sides of the lesion within 1 h; but the kinetics and distribution of modification around the DSB are significantly different. The total accumulation of phosphorylation is reduced by about half when either of the two H2A genes is mutated to the nonphosphorylatable S129A allele. Mec1 activity is limited by the abundance of its ATRIP partner, Ddc2. Moreover, Mec1 is more efficient than Tel1 at phosphorylating chromatin in trans-at distant undamaged sites that are brought into physical proximity to the DSB. We compared experimental data to mathematical models of spreading mechanisms to determine whether the kinases search for target nucleosomes by primarily moving in three dimensions through the nucleoplasm or in one dimension along the chromatin. Bayesian model selection indicates that Mec1 primarily uses a three-dimensional diffusive mechanism, whereas Tel1 undergoes directed motion along the chromatin.


Assuntos
Quebras de DNA de Cadeia Dupla , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Teorema de Bayes , Proteínas de Ciclo Celular/metabolismo , Imunoprecipitação da Cromatina , Difusão , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/genética
9.
J Cancer Res Clin Oncol ; 146(10): 2547-2557, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32671503

RESUMO

INTRODUCTION: Colorectal cancer (CRC) constitutes one of the most prevalent malignancies in the world. Recent research suggests that cancer stem cells (CSCs) are responsible for tumor cell's malignant behavior in CRC. This study has been designed to determinate clinical implications of CSC markers: CD44, DCLK1, Lgr5, and ANXA2 in CRC. MATERIALS AND METHODS: The study was performed on tissue samples which were collected from 89 patients undergoing colectomy. Formalin-fixed paraffin-embedded tissue blocks with representative tumor areas were identified and corded. Immunohistochemical staining was performed using anti-CD44, anti-LGR5, anti-ANXA2, and anti-DCLK1 antibodies. The H-score system was utilized to determine the immunointensity of CRC cells. RESULTS: The lower expression of Lgr5 was significantly correlated with the presence of lymph-node metastases (p = 0.011), while high expression of Lgr5 was statistically significant in vascular invasion in examined cancer tissue samples (p = 0.027). Moreover, a high H-score value of Lgr5 expression was significantly related to a reduced overall survival rate (p = 0.043). CONCLUSION: Our results suggest a strong relationship between CSC marker Lgr5 and vascular invasion, presence of lymph-node metastasis, and overall poor survival. The presence of Lgr5 might be an unfavorable prognostic factor, and its high level in cancer tissue is related to an aggressive course. This marker could also be used to access the effectiveness of the treatment.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Receptores Acoplados a Proteínas-G/metabolismo , Idoso , Anexina A2/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/irrigação sanguínea , Progressão da Doença , Feminino , Humanos , Receptores de Hialuronatos/metabolismo , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Prognóstico , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Acoplados a Proteínas-G/biossíntese , Análise Serial de Tecidos
10.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 40(7): 1062-1065, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32701243

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia characterized by progressive accumulation of fibroblastic foci and destruction of the alveolar structure. Due to an incomplete understanding of the mechanism of the occurrence and progression of IPF, currently no effective means have been available for its early screening or treatment. With a poor overall prognosis, the patients with IPF have a median survival of only 2-4 years. In recent years, several studies have confirmed that dozens of molecules are involved in the development of IPF and can be used as potential biomarkers. These biomarkers play important roles in early diagnosis (such as SP-D, MMP-7, and osteopontin), prognostic evaluation (such as telomerase length, KL-6, mtDNA, HSP-70, LOXL2, CXCL13, miRNA, ICAM-1, and CCL18), and guiding treatment of IPF (such as TOLLIP rs3750920 genotype, SAMS score, and SP-D), and also provide potential therapeutic targets (such as TERT, TERR, RTEC, and PARN).


Assuntos
Biomarcadores , Fibrose Pulmonar Idiopática , Aminoácido Oxirredutases/metabolismo , Biomarcadores/análise , Progressão da Doença , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/terapia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Prognóstico
11.
PLoS Pathog ; 16(6): e1008610, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32603377

RESUMO

Newcastle disease virus (NDV), a member of the Paramyxoviridae family, can activate PKR/eIF2α signaling cascade to shutoff host and facilitate viral mRNA translation during infection, however, the mechanism remains unclear. In this study, we revealed that NDV infection up-regulated host cap-dependent translation machinery by activating PI3K/Akt/mTOR and p38 MAPK/Mnk1 pathways. In addition, NDV infection induced p38 MAPK/Mnk1 signaling participated 4E-BP1 hyperphosphorylation for efficient viral protein synthesis when mTOR signaling is inhibited. Furthermore, NDV NP protein was found to be important for selective cap-dependent translation of viral mRNAs through binding to eIF4E during NDV infection. Taken together, NDV infection activated multiple signaling pathways for selective viral protein synthesis in infected cells, via interaction between viral NP protein and host translation machinery. Our results may help to design novel targets for therapeutic intervention against NDV infection and to understand the NDV anti-oncolytic mechanism.


Assuntos
Proteínas Aviárias , Fator de Iniciação 4E em Eucariotos , Sistema de Sinalização das MAP Quinases , Vírus da Doença de Newcastle , Nucleoproteínas , RNA Mensageiro , RNA Viral , Proteínas Virais , Animais , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Embrião de Galinha , Galinhas , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Vírus da Doença de Newcastle/genética , Vírus da Doença de Newcastle/metabolismo , Nucleoproteínas/biossíntese , Nucleoproteínas/genética , Nucleoproteínas/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Biossíntese de Proteínas , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proteínas Virais/biossíntese , Proteínas Virais/genética , Proteínas Virais/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
Nat Commun ; 11(1): 3422, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647223

RESUMO

The Integrator complex processes 3'-ends of spliceosomal small nuclear RNAs (snRNAs). Furthermore, it regulates transcription of protein coding genes by terminating transcription after unstable pausing. The molecular basis for Integrator's functions remains obscure. Here, we show that INTS10, Asunder/INTS13 and INTS14 form a separable, functional Integrator module. The structure of INTS13-INTS14 reveals a strongly entwined complex with a unique chain interlink. Unexpected structural homology to the Ku70-Ku80 DNA repair complex suggests nucleic acid affinity. Indeed, the module displays affinity for DNA and RNA but prefers RNA hairpins. While the module plays an accessory role in snRNA maturation, it has a stronger influence on transcription termination after pausing. Asunder/INTS13 directly binds Integrator's cleavage module via a conserved C-terminal motif that is involved in snRNA processing and required for spermatogenesis. Collectively, our data establish INTS10-INTS13-INTS14 as a nucleic acid-binding module and suggest that it brings cleavage module and target transcripts into proximity.


Assuntos
Proteínas de Transporte/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ácidos Nucleicos/metabolismo , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Autoantígeno Ku/química , Mutação/genética , Conformação de Ácido Nucleico , Ligação Proteica , Domínios Proteicos , Multimerização Proteica , RNA/química , RNA/metabolismo , Processamento Pós-Transcricional do RNA , Homologia Estrutural de Proteína
13.
PLoS Biol ; 18(7): e3000780, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32687489

RESUMO

Cells adjust to nutrient deprivation by reversible translational shutdown. This is accompanied by maintaining inactive ribosomes in a hibernation state, in which they are bound by proteins with inhibitory and protective functions. In eukaryotes, such a function was attributed to suppressor of target of Myb protein 1 (Stm1; SERPINE1 mRNA-binding protein 1 [SERBP1] in mammals), and recently, late-annotated short open reading frame 2 (Lso2; coiled-coil domain containing short open reading frame 124 [CCDC124] in mammals) was found to be involved in translational recovery after starvation from stationary phase. Here, we present cryo-electron microscopy (cryo-EM) structures of translationally inactive yeast and human ribosomes. We found Lso2/CCDC124 accumulating on idle ribosomes in the nonrotated state, in contrast to Stm1/SERBP1-bound ribosomes, which display a rotated state. Lso2/CCDC124 bridges the decoding sites of the small with the GTPase activating center (GAC) of the large subunit. This position allows accommodation of the duplication of multilocus region 34 protein (Dom34)-dependent ribosome recycling system, which splits Lso2-containing, but not Stm1-containing, ribosomes. We propose a model in which Lso2 facilitates rapid translation reactivation by stabilizing the recycling-competent state of inactive ribosomes.


Assuntos
Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Ribossômicas/química , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Sequência Conservada , Evolução Molecular , Células HEK293 , Humanos , Modelos Moleculares , Peptídeos/química , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Transferência/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ribossomos/ultraestrutura , Saccharomyces cerevisiae/ultraestrutura , Relação Estrutura-Atividade
14.
Arch Cardiovasc Dis ; 113(8-9): 564-571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32680738

RESUMO

The mitochondria produce specific peptides-mitochondrial-derived peptides-that mediate the transcriptional stress response by their translocation into the nucleus and interaction with deoxyribonucleic acid. Mitochondrial-derived peptides are regulators of metabolism. This class of peptides comprises humanin, mitochondrial open reading frame of the 12S ribosomal ribonucleic acid type c (MOTS-c) and small humanin-like peptides (SHLPs). Humanin inhibits mitochondrial complex 1 activity and limits the level of oxidative stress in the cell. Data show that mitochondrial-derived peptides have a role in improving metabolic diseases, such as type 2 diabetes. Perhaps humanin can be used as a marker for mitochondrial function in cardiovascular disease or as a pharmacological strategy in patients with endothelial dysfunction. The goal of this review is to discuss the newly emerging functions of humanin, and its biological role in cardiovascular disorders.


Assuntos
Doenças Cardiovasculares/metabolismo , Sistema Cardiovascular/metabolismo , Mediadores da Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Mitocôndrias/metabolismo , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/fisiopatologia , Sistema Cardiovascular/fisiopatologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mitocôndrias/genética , Estresse Oxidativo , Transdução de Sinais , Regulação para Cima
15.
Mol Cell Biol ; 40(18)2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32631902

RESUMO

hRpn13/ADRM1 links substrate recruitment with deubiquitination at the proteasome through its proteasome- and ubiquitin-binding Pru domain and DEUBAD domain, which binds and activates deubiquitinating enzyme (DUB) UCHL5/Uch37. Here, we edit the HCT116 colorectal cancer cell line to delete part of the hRpn13 Pru, producing cells that express truncated hRpn13 (trRpn13), which is competent for UCHL5 binding but defective for proteasome interaction. trRpn13 cells demonstrate reduced levels of proteasome-bound ubiquitinated proteins, indicating that the loss of hRpn13 function at proteasomes cannot be fully compensated for by the two other dedicated substrate receptors (hRpn1 and hRpn10). Previous studies indicated that the loss of full-length hRpn13 causes a corresponding reduction of UCHL5. We find UCHL5 levels unaltered in trRpn13 cells, but hRpn11 is elevated in ΔhRpn13 and trRpn13 cells, perhaps from cell stress. Despite the ∼90 DUBs in human cells, including two others in addition to UCHL5 at the proteasome, we found deletion of UCHL5 from HCT116 cells to cause increased levels of ubiquitinated proteins in whole-cell extract and at proteasomes, suggesting that UCHL5 activity cannot be fully assumed by other DUBs. We also report anticancer molecule RA190, which binds covalently to hRpn13 and UCHL5, to require hRpn13 Pru and not UCHL5 for cytotoxicity.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Chaperonas Moleculares/metabolismo , Ubiquitina Tiolesterase/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Citoplasma/metabolismo , Células HCT116 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Glicoproteínas de Membrana/metabolismo , Chaperonas Moleculares/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Ubiquitina/metabolismo , Ubiquitina Tiolesterase/genética , Proteínas Ubiquitinadas/metabolismo
16.
Nat Commun ; 11(1): 3603, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32681107

RESUMO

Members of the PR/SET domain-containing (PRDM) family of zinc finger transcriptional regulators play diverse developmental roles. PRDM10 is a yet uncharacterized family member, and its function in vivo is unknown. Here, we report an essential requirement for PRDM10 in pre-implantation embryos and embryonic stem cells (mESCs), where loss of PRDM10 results in severe cell growth inhibition. Detailed genomic and biochemical analyses reveal that PRDM10 functions as a sequence-specific transcription factor. We identify Eif3b, which encodes a core component of the eukaryotic translation initiation factor 3 (eIF3) complex, as a key downstream target, and demonstrate that growth inhibition in PRDM10-deficient mESCs is in part mediated through EIF3B-dependent effects on global translation. Our work elucidates the molecular function of PRDM10 in maintaining global translation, establishes its essential role in early embryonic development and mESC homeostasis, and offers insights into the functional repertoire of PRDMs as well as the transcriptional mechanisms regulating translation.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Camundongos/metabolismo , Fatores de Transcrição/metabolismo , Animais , Desenvolvimento Embrionário , Células-Tronco Embrionárias/metabolismo , Fatores de Iniciação em Eucariotos/genética , Fatores de Iniciação em Eucariotos/metabolismo , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Camundongos/embriologia , Camundongos/genética , Biossíntese de Proteínas , Fatores de Transcrição/genética
17.
Nat Commun ; 11(1): 3687, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703941

RESUMO

Microglia, resident immune cells of the CNS, are thought to defend against infections. Toxoplasma gondii is an opportunistic infection that can cause severe neurological disease. Here we report that during T. gondii infection a strong NF-κB and inflammatory cytokine transcriptional signature is overrepresented in blood-derived macrophages versus microglia. Interestingly, IL-1α is enriched in microglia and IL-1ß in macrophages. We find that mice lacking IL-1R1 or IL-1α, but not IL-1ß, have impaired parasite control and immune cell infiltration within the brain. Further, we show that microglia, not peripheral myeloid cells, release IL-1α ex vivo. Finally, we show that ex vivo IL-1α release is gasdermin-D dependent, and that gasdermin-D and caspase-1/11 deficient mice show deficits in brain inflammation and parasite control. These results demonstrate that microglia and macrophages are differently equipped to propagate inflammation, and that in chronic T. gondii infection, microglia can release the alarmin IL-1α, promoting neuroinflammation and parasite control.


Assuntos
Interleucina-1alfa/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Microglia/imunologia , Proteínas de Ligação a Fosfato/metabolismo , Toxoplasma/imunologia , Toxoplasmose Cerebral/imunologia , Animais , Encéfalo/citologia , Encéfalo/imunologia , Encéfalo/parasitologia , Encéfalo/patologia , Células Cultivadas , Doença Crônica , Modelos Animais de Doenças , Humanos , Interleucina-1alfa/genética , Interleucina-1alfa/imunologia , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Microglia/metabolismo , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/imunologia , Toxoplasma/isolamento & purificação , Toxoplasmose Cerebral/sangue , Toxoplasmose Cerebral/parasitologia , Toxoplasmose Cerebral/patologia
18.
PLoS One ; 15(6): e0233643, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479555

RESUMO

Chronic subdural hematoma (CSDH) is an angiogenic and inflammatory disease. Toll-like receptors (TLRs) transduce intracellular signals, resulting in the activation of nuclear factor κB (NF-κB), which leads to the production of inflammatory cytokines. High-mobility group box 1 (HMGB1) functions as a mediator of inflammatory responses through TLRs. In this study, we examined the expression of HMGB1 and components of the Toll-like receptor and NF-κB signaling pathways in the outer membrane of CSDH. Eight patients whose outer membrane was successfully obtained during trepanation surgery were included in this study. The expression of TLR4, myeloid differentiation factor 88 (MyD88), interleukin-1 receptor-associated kinase 4 (IRAK4), TNF receptor-associated factor 6 (TRAF6), TGFß-activated kinase 1 (Tak1), interferon regulatory factors 3 (IRF3), IκB kinase ß (IKKß), IKKγ, IκBε, IκBα, NF-κB/p65 and ß-actin was examined by Western blot analysis. The expression of TLR4, NF-κB/p65 and interleukin-6 (IL-6) was also examined by immunohistochemistry. The concentrations of HMGB1 and IL-6 in CSDH fluids were measured using ELISA kits. Above-mentioned molecules were detected in all cases. In addition, TLR4, NF-κB/p65 and IL-6 were localized in the endothelial cells of vessels within CSDH outer membranes. The concentrations of HMGB1 and IL-6 in CSDH fluids were significantly higher than that in the CSF and serum. There existed a correlation between the concentrations of HMGB1 and IL-6 in CSDH fluids. Our data suggest that HMGB1 in CSDH fluids produces the inflammatory cytokine IL-6 in endothelial cells through the Toll-like receptor and NF-κB signaling pathways. Anti-HMGB1 therapy might be a useful method to treat the growth of CSDH.


Assuntos
Proteína HMGB1/metabolismo , Hematoma Subdural Crônico/metabolismo , Interleucina-6/metabolismo , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Idoso , Idoso de 80 Anos ou mais , Endotélio Vascular/metabolismo , Feminino , Proteína HMGB1/genética , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Quinases Associadas a Receptores de Interleucina-1/genética , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Interleucina-6/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Masculino , Pessoa de Meia-Idade , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/genética , Transdução de Sinais , Receptor 4 Toll-Like/genética
19.
Cancer Sci ; 111(9): 3210-3221, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32519357

RESUMO

Non-small-cell lung cancer (NSCLC) is the leading global cause of cancer-related death. Due to the lack of reliable diagnostic or prognostic biomarkers, the prognosis of NSCLC remains poor. Consequently, there is an urgent need to explore the mechanisms underlying this condition in order to identify effective biomarkers. G-protein-signaling modulator 2 (GPSM2) is widely recognized as a determinant of mitotic spindle orientation. However, its role in cancer, especially NSCLC, remains uncertain. In this study, we found that GPSM2 was downregulated in NSCLC tissues and was correlated with a poor prognosis. Furthermore, the knockdown of GPSM2 promoted NSCLC cell metastasis in vitro and in vivo and accelerated the process of epithelial-mesenchymal transition (EMT). Mechanistically, we showed that silencing GPSM2 induced cell metastasis and EMT through the ERK/glycogen synthase kinase-3ß/Snail pathway. These results confirm that GPSM2 plays an important role in NSCLC. Moreover, GPSM2, as an independent prognostic factor, could be a potential prognostic biomarker and drug target for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Fatores de Transcrição da Família Snail/genética , Adulto , Idoso , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Bases de Dados Genéticas , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Fatores de Transcrição da Família Snail/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
20.
PLoS Pathog ; 16(6): e1008597, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32511265

RESUMO

During infection of neurons by alphaherpesviruses including Pseudorabies virus (PRV) and Herpes simplex virus type 1 (HSV-1) viral nucleocapsids assemble in the cell nucleus, become enveloped in the cell body then traffic into and down axons to nerve termini for spread to adjacent epithelia. The viral membrane protein US9p and the membrane glycoprotein heterodimer gE/gI play critical roles in anterograde spread of both HSV-1 and PRV, and several models exist to explain their function. Biochemical studies suggest that PRV US9p associates with the kinesin-3 motor KIF1A in a gE/gI-stimulated manner, and the gE/gI-US9p complex has been proposed to recruit KIF1A to PRV for microtubule-mediated anterograde trafficking into or along the axon. However, as loss of gE/gI-US9p essentially abolishes delivery of alphaherpesviruses to the axon it is difficult to determine the microtubule-dependent trafficking properties and motor-composition of Δ(gE/gI-US9p) particles. Alternatively, studies in HSV-1 have suggested that gE/gI and US9p are required for the appearance of virions in the axon because they act upstream, to help assemble enveloped virions in the cell body. We prepared Δ(gE/gI-US9p) mutant, and control parental PRV particles from differentiated cultured neuronal or porcine kidney epithelial cells and quantitated the efficiency of virion assembly, the properties of microtubule-dependent transport and the ability of viral particles to recruit kinesin motors. We find that loss of gE/gI-US9p has no significant effect upon PRV particle assembly but leads to greatly diminished plus end-directed traffic, and enhanced minus end-directed and bidirectional movement along microtubules. PRV particles prepared from infected differentiated mouse CAD neurons were found to be associated with either kinesin KIF1A or kinesin KIF5C, but not both. Loss of gE/gI-US9p resulted in failure to recruit KIF1A and KF5C, but did not affect dynein binding. Unexpectedly, while KIF5C was expressed in undifferentiated and differentiated CAD neurons it was only found associated with PRV particles prepared from differentiated cells.


Assuntos
Herpesvirus Suídeo 1 , Peptídeos e Proteínas de Sinalização Intracelular , Cinesina/metabolismo , Lipoproteínas , Microtúbulos/metabolismo , Pseudorraiva , Proteínas do Envelope Viral , Proteínas Virais , Liberação de Vírus , Animais , Transporte Biológico Ativo , Linhagem Celular , Deleção de Genes , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Cinesina/genética , Lipoproteínas/genética , Lipoproteínas/metabolismo , Microtúbulos/genética , Microtúbulos/virologia , Pseudorraiva/genética , Pseudorraiva/metabolismo , Pseudorraiva/patologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
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