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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.
PLoS Biol ; 18(8): e3000807, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760056

RESUMO

Radiotherapy is a commonly used conditioning regimen for bone marrow transplantation (BMT). Cytotoxicity limits the use of this life-saving therapy, but the underlying mechanisms remain poorly defined. Here, we use the syngeneic mouse BMT model to test the hypothesis that lethal radiation damages tissues, thereby unleashing signals that indiscriminately activate the inflammasome pathways in host and transplanted cells. We find that a clinically relevant high dose of radiation causes severe damage to bones and the spleen through mechanisms involving the NLRP3 and AIM2 inflammasomes but not the NLRC4 inflammasome. Downstream, we demonstrate that gasdermin D (GSDMD), the common effector of the inflammasomes, is also activated by radiation. Remarkably, protection against the injury induced by deadly ionizing radiation occurs only when NLRP3, AIM2, or GSDMD is lost simultaneously in both the donor and host cell compartments. Thus, this study reveals a continuum of the actions of lethal radiation relayed by the inflammasome-GSDMD axis, initially affecting recipient cells and ultimately harming transplanted cells as they grow in the severely injured and toxic environment. This study also suggests that therapeutic targeting of inflammasome-GSDMD signaling has the potential to prevent the collateral effects of intense radiation regimens.


Assuntos
Células da Medula Óssea/efeitos da radiação , Transplante de Medula Óssea , Proteínas de Ligação a DNA/genética , Inflamassomos/efeitos da radiação , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas de Ligação a Fosfato/genética , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proteínas de Ligação a DNA/deficiência , Feminino , Fêmur/citologia , Fêmur/metabolismo , Regulação da Expressão Gênica , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Proteínas de Ligação a Fosfato/deficiência , Piroptose/genética , Piroptose/efeitos da radiação , Transdução de Sinais , Baço/metabolismo , Baço/patologia , Baço/efeitos da radiação , Transplante Isogênico , Irradiação Corporal Total , Raios X
4.
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
5.
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
6.
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
7.
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
8.
Life Sci ; 257: 118089, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659369

RESUMO

AIM: Hepatitis B virus (HBV) is a major cause of a variety of liver diseases. Existing antiviral drugs cannot eradicate HBV from our body, and the main reason is unclear on the molecular mechanism of HBV replication. Flap endonuclease 1 (FEN1) can repair relaxed circular DNA (HBV rcDNA) to covalently closed circular DNA (HBV cccDNA) that promotes HBV DNA replication, while its specific regulatory detail remains unclear. In addition, miR-146a is close related to regulation in HBV replication. This study aims to explore whether miR-146a regulates HBV cccDNA formation through FEN1. MAIN METHODS: We investigated the expression of miR-146a, FEN1 and HBV copies in HBV stable replication cell line HepG2.2.15 and its parent cell line HepG2 transfected miR-146a and FEN1 plasmid by qRT-PCR and western blot, to identify the cooperation of Argonaute-2 (Ago2) and miR-146a by Ago2 siRNA and Ago2 RNA Binding Protein Immunoprecipitation (RIP). KEY FINDINGS: Compared with the control group, we found that the expression of miR-146a was significantly up-regulated in HepG2.2.15, and the expression of FEN1 and HBV copies were also significantly up-regulated. On contrary, the expression of target gene of miR-146a, interleukin-1 receptor-associated kinase 1 (IRAK1) and tumor necrosis factor receptor-associated factor-6 (TRAF6), was significantly decreased in HepG2.2.15. With the use of Ago2 siRNA and then Ago2 RIP, we found that Ago2 performed as a carrier for miR-146a to promote HBV replication. SIGNIFICANCE: The results suggest a novel miR-146a â†’ FEN1 â†’ HBV DNA regulatory axis in HBV replication life. Ago2 cooperates with miR-146a to regulate the transcription and expression level of FEN1 protein through the downstream target gene IRAK1/TRAF6, and to promote HBV replication.


Assuntos
Proteínas Argonauta/genética , Vírus da Hepatite B/fisiologia , MicroRNAs/genética , Replicação Viral/genética , DNA Circular/genética , DNA Viral/genética , Endonucleases Flap/genética , Células Hep G2 , Humanos , Quinases Associadas a Receptores de Interleucina-1/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética
9.
Nucleic Acids Res ; 48(15): 8474-8489, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32652040

RESUMO

Highly toxic DNA double-strand breaks (DSBs) readily trigger the DNA damage response (DDR) in cells, which delays cell cycle progression to ensure proper DSB repair. In Saccharomyces cerevisiae, mitotic S phase (20-30 min) is lengthened upon DNA damage. During meiosis, Spo11-induced DSB onset and repair lasts up to 5 h. We report that the NH2-terminal domain (NTD; residues 1-66) of Rad51 has dual functions for repairing DSBs during vegetative growth and meiosis. Firstly, Rad51-NTD exhibits autonomous expression-enhancing activity for high-level production of native Rad51 and when fused to exogenous ß-galactosidase in vivo. Secondly, Rad51-NTD is an S/T-Q cluster domain (SCD) harboring three putative Mec1/Tel1 target sites. Mec1/Tel1-dependent phosphorylation antagonizes the proteasomal degradation pathway, increasing the half-life of Rad51 from ∼30 min to ≥180 min. Our results evidence a direct link between homologous recombination and DDR modulated by Rad51 homeostasis.


Assuntos
Quebras de DNA de Cadeia Dupla , Endodesoxirribonucleases/genética , Meiose/genética , Rad51 Recombinase/genética , Proteínas de Saccharomyces cerevisiae/genética , Dano ao DNA/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Regulação Fúngica da Expressão Gênica/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fosforilação/genética , Complexo de Endopeptidases do Proteassoma/genética , Domínios Proteicos/genética , Proteínas Serina-Treonina Quinases/genética , Proteólise , Saccharomyces cerevisiae/genética , beta-Galactosidase/genética
10.
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
11.
PLoS One ; 15(7): e0236361, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706793

RESUMO

MEdiator of cell MOtility1 (MEMO1) is a ubiquitously expressed redox protein involved in extracellular ligand-induced cell signaling. We previously reported that inducible whole-body Memo1 KO (cKO) mice displayed a syndrome of premature aging and disturbed mineral metabolism partially recapitulating the phenotype observed in Klotho or Fgf23-deficient mouse models. Here, we aimed at delineating the contribution of systemic mineral load on the Memo1 cKO mouse phenotype. We attempted to rescue the Memo1 cKO phenotype by depleting phosphate or vitamin D from the diet, but did not observe any effect on survival. However, we noticed that, by contrast to Klotho or Fgf23-deficient mouse models, Memo1 cKO mice did not present any soft-tissue calcifications and displayed even a decreased serum calcification propensity. We identified higher serum magnesium levels as the main cause of protection against calcifications. Expression of genes encoding intestinal and renal magnesium channels and the regulator epidermal growth factor were increased in Memo1 cKO. In order to check whether magnesium reabsorption in the kidney alone was driving the higher magnesemia, we generated a kidney-specific Memo1 KO (kKO) mouse model. Memo1 kKO mice also displayed higher magnesemia and increased renal magnesium channel gene expression. Collectively, these data identify MEMO1 as a novel regulator of magnesium homeostasis and systemic calcification propensity, by regulating expression of the main magnesium channels.


Assuntos
Calcinose/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Rim/metabolismo , Magnésio/sangue , Animais , Calcinose/genética , Feminino , Homeostase , Peptídeos e Proteínas de Sinalização Intracelular/genética , Canais Iônicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatos/metabolismo , Vitamina D/metabolismo
12.
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
13.
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
14.
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
15.
Proc Natl Acad Sci U S A ; 117(25): 14433-14443, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513747

RESUMO

During infection, the bacterial pathogen Legionella pneumophila manipulates a variety of host cell signaling pathways, including the Hippo pathway which controls cell proliferation and differentiation in eukaryotes. Our previous studies revealed that L. pneumophila encodes the effector kinase LegK7 which phosphorylates MOB1A, a highly conserved scaffold protein of the Hippo pathway. Here, we show that MOB1A, in addition to being a substrate of LegK7, also functions as an allosteric activator of its kinase activity. A crystallographic analysis of the LegK7-MOB1A complex revealed that the N-terminal half of LegK7 is structurally similar to eukaryotic protein kinases, and that MOB1A directly binds to the LegK7 kinase domain. Substitution of interface residues critical for complex formation abrogated allosteric activation of LegK7 both in vitro and within cells and diminished MOB1A phosphorylation. Importantly, the N-terminal extension (NTE) of MOB1A not only regulated complex formation with LegK7 but also served as a docking site for downstream substrates such as the transcriptional coregulator YAP1. Deletion of the NTE from MOB1A or addition of NTE peptides as binding competitors attenuated YAP1 recruitment to and phosphorylation by LegK7. By providing mechanistic insight into the formation and regulation of the LegK7-MOB1A complex, our study unravels a sophisticated molecular mimicry strategy that is used by L. pneumophila to take control of the host cell Hippo pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Bactérias/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Legionella pneumophila/metabolismo , Proteínas Quinases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Regulação Alostérica , Animais , Proteínas de Bactérias/genética , Proteínas de Ciclo Celular/metabolismo , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Legionella pneumophila/patogenicidade , Doença dos Legionários/microbiologia , Doença dos Legionários/patologia , Macrófagos Alveolares/microbiologia , Macrófagos Alveolares/patologia , Camundongos , Simulação de Dinâmica Molecular , Mimetismo Molecular , Fosforilação , Ligação Proteica , Proteínas Quinases/genética , Células RAW 264.7 , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo
16.
Nat Commun ; 11(1): 3111, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561725

RESUMO

Midbrain dopaminergic (DA) axons make long longitudinal projections towards the striatum. Despite the importance of DA striatal innervation, processes involved in establishment of DA axonal connectivity remain largely unknown. Here we demonstrate a striatal-specific requirement of transcriptional regulator Nolz1 in establishing DA circuitry formation. DA projections are misguided and fail to innervate the striatum in both constitutive and striatal-specific Nolz1 mutant embryos. The lack of striatal Nolz1 expression results in nigral to pallidal lineage conversion of striatal projection neuron subtypes. This lineage switch alters the composition of secreted factors influencing DA axonal tract formation and renders the striatum non-permissive for dopaminergic and other forebrain tracts. Furthermore, transcriptomic analysis of wild-type and Nolz1-/- mutant striatal tissue led to the identification of several secreted factors that underlie the observed guidance defects and proteins that promote DA axonal outgrowth. Together, our data demonstrate the involvement of the striatum in orchestrating dopaminergic circuitry formation.


Assuntos
Orientação de Axônios/fisiologia , Axônios/fisiologia , Corpo Estriado/crescimento & desenvolvimento , Neurônios Dopaminérgicos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Carbocianinas/administração & dosagem , Corpo Estriado/diagnóstico por imagem , Embrião de Mamíferos , Feminino , Corantes Fluorescentes/administração & dosagem , Peptídeos e Proteínas de Sinalização Intracelular/genética , Microscopia Intravital , Camundongos Knockout , Técnicas Analíticas Microfluídicas , Microinjeções , Microscopia Confocal , Rede Nervosa/fisiologia , Proteínas do Tecido Nervoso/genética , Técnicas de Cultura de Tecidos
17.
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
18.
Cell Prolif ; 53(7): e12853, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32537867

RESUMO

BACKGROUND: Hypoxia-inducible factors (HIFs) are thought to play important roles in the carcinogenesis and progression of VHL-deficient clear cell renal cell carcinoma (ccRCC). METHODS: The roles of HIF-1/2α in VHL-deficient clear cell renal cell carcinoma were evaluated by bioinformatics analysis, immunohistochemistry staining and Kaplan-Meier survival analysis. The downstream genes that counteract the cancer-promoting effect of HIF were analysed by unbiased proteomics and verified by in vitro and in vivo assays. RESULTS: There was no correlation between the high protein level of HIF-1/2α and the poor prognosis of ccRCC patients in our large set of clinical data. Furthermore, NDRG1 was found to be up-regulated by both HIF-1α and -2α at the cellular level and in ccRCC tissues. Intriguingly, the high NDRG1 expression was correlated with lower Furman grade, TNM stage and longer survival for ccRCC patients compared with the low NDRG1 expression. In addition, NDRG1 suppressed the expression of series oncogenes as well as the proliferation, metastasis and invasion of VHL-deficient ccRCC cells in vitro and vivo. CONCLUSIONS: Our study demonstrated that HIF downstream gene of NDRG1 may counteract the cancer-promoting effect of HIF. These results provided evidence that NDRG1 may be a potential prognostic biomarker as well as a therapeutic target in ccRCC.


Assuntos
Carcinoma de Células Renais/genética , Proteínas de Ciclo Celular/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Renais/genética , Regulação para Cima/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Renais/patologia , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Gravidez , Ativação Transcricional/genética , Adulto Jovem
19.
Nat Commun ; 11(1): 2797, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493999

RESUMO

Fat distribution is an independent cardiometabolic risk factor. However, its molecular and cellular underpinnings remain obscure. Here we demonstrate that two independent GWAS signals at RSPO3, which are associated with increased body mass index-adjusted waist-to-hip ratio, act to specifically increase RSPO3 expression in subcutaneous adipocytes. These variants are also associated with reduced lower-body fat, enlarged gluteal adipocytes and insulin resistance. Based on human cellular studies RSPO3 may limit gluteofemoral adipose tissue (AT) expansion by suppressing adipogenesis and increasing gluteal adipocyte susceptibility to apoptosis. RSPO3 may also promote upper-body fat distribution by stimulating abdominal adipose progenitor (AP) proliferation. The distinct biological responses elicited by RSPO3 in abdominal versus gluteal APs in vitro are associated with differential changes in WNT signalling. Zebrafish carrying a nonsense rspo3 mutation display altered fat distribution. Our study identifies RSPO3 as an important determinant of peripheral AT storage capacity.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Distribuição da Gordura Corporal , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Trombospondinas/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Adipócitos/efeitos dos fármacos , Tecido Adiposo/metabolismo , Adiposidade/genética , Adulto , Alelos , Animais , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Tamanho Celular/efeitos dos fármacos , Doxiciclina/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Caracteres Sexuais , Células-Tronco/metabolismo , Trombospondinas/genética , Relação Cintura-Quadril , Via de Sinalização Wnt/efeitos dos fármacos , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
20.
Int J Infect Dis ; 97: 47-53, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32531432

RESUMO

PURPOSE: To explore the molecular genetic mechanisms underlying different responsiveness to Enterovirus 71 (EV71) vaccine. METHODS: We recruited 10,245 healthy children into a phase 3 clinical trial to evaluate the efficacy of EV71 vaccine in 2012. Fifty subjects from the trial were divided into the potent immune response group (20 subjects) and the ineffective immune response group (30 subjects). Whole-exome sequencing was performed for these 50 samples and we conducted bioinformatics analyses based on online public database. RESULTS: A total of 222,180 germline variants were detected across 50 subjects. Single nucleotide variant (SNV)-based screening of the subjects with potent or ineffective immune response allowed the identification of a potentially detrimental heterozygous missense variant (c.3784C>T) in EEA1. We also retained TRIM59 and ABCA7 genes that contain different loss of function (LoF) variants shared in two cases and involved in the immune response process. Then, we conducted high-resolution typing of 9 classical HLA genes, HLA-DRB1*03:01, HLA-DQA1*05:01 and HLA-DQB1*02:01 alleles were frequently (recurrence ≥5) observed only in ineffective immune responders. CONCLUSIONS: Our study is a meaningful attempt on the comparison of genomic profiles between potent and ineffective immune responders induced by EV71 vaccine, and several candidate potentially detrimental genes were identified.


Assuntos
Enterovirus Humano A/imunologia , Vacinas Virais/imunologia , Transportadores de Cassetes de Ligação de ATP/genética , Alelos , Pré-Escolar , China , Feminino , Variação Genética , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas com Motivo Tripartido/genética , Sequenciamento Completo do Exoma
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