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1.
PLoS One ; 15(9): e0238420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32931492

RESUMO

BACKGROUND: Patients diagnosed with Oral Floor Squamous Cell Carcinoma (OFSCC) face considerable challenges in physiology and psychology. This study explored prognostic signatures to predict prognosis in OFSCC through a detailed transcriptomic analysis. METHOD: We built an interactive competing endogenous RNA (ceRNA) network that included lncRNAs, miRNAs and mRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to predict the gene functions and regulatory pathways of mRNAs. Least absolute shrinkage and selection operator algorithm (LASSO) analysis and Cox regression analysis were used to screen prognosis factors. The Kaplan-Meier method was used to analyze the survival rate of prognosis factors. Risk score was used to assess the reliability of the prediction model. RESULTS: A specific ceRNA network consisting of 56 mRNAs, 16 miRNAs and 31 lncRNAs was established. Three key genes (HOXC13, TGFBR3, KLHL40) and 4 clinical factors (age, gender, TNM, and clinical stage) were identified and effectively predicted the for survival time. The expression of a gene signature was validated in two external validation cohorts. The signature (areas under the curve of 3 and 5 years were 0.977 and 0.982, respectively) showed high prognostic accuracy in the complete TCGA cohort. CONCLUSIONS: Our study successfully developed an extensive ceRNA network for OFSCC and further identified a 3-mRNA and 4-clinical-factor signature, which may serve as a biomarker.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Neoplasias Bucais/genética , RNA Neoplásico/genética , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Bases de Dados de Ácidos Nucleicos , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Proteínas de Homeodomínio/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Soalho Bucal , Neoplasias Bucais/mortalidade , Proteínas Musculares/genética , Prognóstico , Proteoglicanas/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Fatores de Risco
2.
Int Heart J ; 61(5): 1079-1083, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32879264

RESUMO

A Japanese girl with polycystic kidney disease (PKD) developed normally, but at 8 months of age, she was hospitalized for acute onset dyspnea. On the day after admission to hospital, her general condition suddenly became worse. An echocardiogram showed left ventricular dilatation with thin walls, severe mitral valve regurgitation, and a reduced ejection fraction. She died of acute cardiac failure 3 hours after the sudden change. Postmortem analysis with light microscopy showed disarray of cardiomyocytes without obvious infiltration of lymphocytes, and we diagnosed her heart failure as idiopathic dilated cardiomyopathy (DCM). Clinical exome sequencing showed compound heterozygous variants in JPH2 (p.T237A/p.I414L) and a heterozygous nonsense mutation in PKD1 (p.Q4193*). To date, several variants in the JPH2 gene have been reported to be pathogenic for adult-onset hypertrophic cardiomyopathy or DCM in an autosomal dominant manner and infantile-onset DCM in an autosomal recessive manner. Additionally, autosomal dominant polycystic kidney disease is a systemic disease associated with several extrarenal manifestations, such as cardiomyopathy. Here we report a sudden infant death case of DCM and discuss the genetic variants of DCM and PKD.


Assuntos
Cardiomiopatia Dilatada/genética , Proteínas de Membrana/genética , Proteínas Musculares/genética , Rim Policístico Autossômico Dominante/genética , Canais de Cátion TRPP/genética , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/patologia , Morte Súbita Cardíaca/etiologia , Evolução Fatal , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/etiologia , Heterozigoto , Humanos , Lactente , Insuficiência da Valva Mitral/etiologia , Miocárdio/patologia , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue
3.
Proc Natl Acad Sci U S A ; 117(33): 20159-20170, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747553

RESUMO

Although immune checkpoint blockade (ICB) therapy has revolutionized cancer treatment, many patients do not respond or develop resistance to ICB. N6 -methylation of adenosine (m6A) in RNA regulates many pathophysiological processes. Here, we show that deletion of the m6A demethylase Alkbh5 sensitized tumors to cancer immunotherapy. Alkbh5 has effects on m6A density and splicing events in tumors during ICB. Alkbh5 modulates Mct4/Slc16a3 expression and lactate content of the tumor microenvironment and the composition of tumor-infiltrating Treg and myeloid-derived suppressor cells. Importantly, a small-molecule Alkbh5 inhibitor enhanced the efficacy of cancer immunotherapy. Notably, the ALKBH5 gene mutation and expression status of melanoma patients correlate with their response to immunotherapy. Our results suggest that m6A demethylases in tumor cells contribute to the efficacy of immunotherapy and identify ALKBH5 as a potential therapeutic target to enhance immunotherapy outcome in melanoma, colorectal, and potentially other cancers.


Assuntos
Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Vacinas Anticâncer/imunologia , Lactatos/metabolismo , Melanoma/metabolismo , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T Reguladores/fisiologia , Homólogo AlkB 5 da RNA Desmetilase/genética , Anticorpos , Citocinas/genética , Citocinas/metabolismo , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Melanoma/terapia , Metiltransferases/genética , Metiltransferases/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Células Supressoras Mieloides/fisiologia , Sítios de Splice de RNA , Processamento de RNA , Simportadores/genética , Simportadores/metabolismo , Transcriptoma , Microambiente Tumoral , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Proc Natl Acad Sci U S A ; 117(35): 21288-21298, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817544

RESUMO

The endoplasmic reticulum (ER) is the reservoir for calcium in cells. Luminal calcium levels are determined by calcium-sensing proteins that trigger calcium dynamics in response to calcium fluctuations. Here we report that Selenoprotein N (SEPN1) is a type II transmembrane protein that senses ER calcium fluctuations by binding this ion through a luminal EF-hand domain. In vitro and in vivo experiments show that via this domain, SEPN1 responds to diminished luminal calcium levels, dynamically changing its oligomeric state and enhancing its redox-dependent interaction with cellular partners, including the ER calcium pump sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA). Importantly, single amino acid substitutions in the EF-hand domain of SEPN1 identified as clinical variations are shown to impair its calcium-binding and calcium-dependent structural changes, suggesting a key role of the EF-hand domain in SEPN1 function. In conclusion, SEPN1 is a ER calcium sensor that responds to luminal calcium depletion, changing its oligomeric state and acting as a reductase to refill ER calcium stores.


Assuntos
Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas Sensoras de Cálcio Intracelular/metabolismo , Proteínas Musculares/metabolismo , Selenoproteínas/metabolismo , Células HeLa , Humanos , Proteínas Sensoras de Cálcio Intracelular/genética , Proteínas Musculares/genética , Oxirredução , Selenoproteínas/genética
5.
Am J Physiol Cell Physiol ; 319(2): C419-C431, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32639875

RESUMO

Small noncoding microRNAs (miRNAs) are important regulators of skeletal muscle size, and circulating miRNAs within extracellular vesicles (EVs) may contribute to atrophy and its associated systemic effects. The purpose of this study was to understand how muscle atrophy and regrowth alter in vivo serum EV miRNA content. We also associated changes in serum EV miRNA with protein synthesis, protein degradation, and miRNA within muscle, kidney, and liver. We subjected adult (10 mo) F344/BN rats to three conditions: weight bearing (WB), hindlimb suspension (HS) for 7 days to induce muscle atrophy, and HS for 7 days followed by 7 days of reloading (HSR). Microarray analysis of EV miRNA content showed that the overall changes in serum EV miRNA were predicted to target major anabolic, catabolic, and mechanosensitive pathways. MiR-203a-3p was the only miRNA demonstrating substantial differences in HS EVs compared with WB. There was a limited association of EV miRNA content to the corresponding miRNA content within the muscle, kidney, or liver. Stepwise linear regression demonstrated that EV miR-203a-3p was correlated with muscle mass and muscle protein synthesis and degradation across all conditions. Finally, EV miR-203a-3p expression was significantly decreased in human subjects who underwent unilateral lower limb suspension (ULLS) to induce muscle atrophy. Altogether, we show that serum EV miR-203a-3p expression is related to skeletal muscle protein turnover and atrophy. We suggest that serum EV miR-203a-3p content may be a useful biomarker and future work should investigate whether serum EV miR-203a-3p content is mechanistically linked to protein synthesis and degradation.


Assuntos
MicroRNAs/genética , Músculo Esquelético/metabolismo , Atrofia Muscular/genética , Transtornos Musculares Atróficos/genética , Animais , Biomarcadores/metabolismo , Vesículas Extracelulares/genética , Elevação dos Membros Posteriores , Humanos , Rim/metabolismo , Fígado/metabolismo , Análise em Microsséries , Proteínas Musculares/genética , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Transtornos Musculares Atróficos/metabolismo , Transtornos Musculares Atróficos/patologia , Ratos
6.
PLoS One ; 15(7): e0236193, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32692755

RESUMO

BACKGROUND: Naturally occurring human genetic variants provide a valuable tool to identify drug targets and guide drug prioritization and clinical trial design. Ivabradine is a heart rate lowering drug with protective effects on heart failure despite increasing the risk of atrial fibrillation. In patients with coronary artery disease without heart failure, the drug does not protect against major cardiovascular adverse events prompting questions about the ability of genetics to have predicted those effects. This study evaluates the effect of a variant in HCN4, ivabradine's drug target, on safety and efficacy endpoints. METHODS: We used genetic association testing and Mendelian randomization to predict the effect of ivabradine and heart rate lowering on cardiovascular outcomes. RESULTS: Using data from the UK Biobank and large GWAS consortia, we evaluated the effect of a heart rate-reducing genetic variant at the HCN4 locus encoding ivabradine's drug target. These genetic association analyses showed increases in risk for atrial fibrillation (OR 1.09, 95% CI: 1.06-1.13, P = 9.3 ×10-9) in the UK Biobank. In a cause-specific competing risk model to account for the increased risk of atrial fibrillation, the HCN4 variant reduced incident heart failure in participants that did not develop atrial fibrillation (HR 0.90, 95% CI: 0.83-0.98, P = 0.013). In contrast, the same heart rate reducing HCN4 variant did not prevent a composite endpoint of myocardial infarction or cardiovascular death (OR 0.99, 95% CI: 0.93-1.04, P = 0.61). CONCLUSION: Genetic modelling of ivabradine recapitulates its benefits in heart failure, promotion of atrial fibrillation, and neutral effect on myocardial infarction.


Assuntos
Ivabradina/farmacologia , Modelos Genéticos , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto , Idoso , Alelos , Doenças Cardiovasculares/fisiopatologia , Determinação de Ponto Final , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/genética , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Masculino , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Proteínas Musculares/genética , Canais de Potássio/genética , Fatores de Risco
7.
Proc Natl Acad Sci U S A ; 117(30): 17864-17875, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32669432

RESUMO

Early pregnancy loss affects ∼15% of all implantation-confirmed human conceptions. However, evolutionarily conserved molecular mechanisms that regulate self-renewal of trophoblast progenitors and their association with early pregnancy loss are poorly understood. Here, we provide evidence that transcription factor TEAD4 ensures survival of postimplantation mouse and human embryos by controlling self-renewal and stemness of trophoblast progenitors within the placenta primordium. In an early postimplantation mouse embryo, TEAD4 is selectively expressed in trophoblast stem cell-like progenitor cells (TSPCs), and loss of Tead4 in postimplantation mouse TSPCs impairs their self-renewal, leading to embryonic lethality before embryonic day 9.0, a developmental stage equivalent to the first trimester of human gestation. Both TEAD4 and its cofactor, yes-associated protein 1 (YAP1), are specifically expressed in cytotrophoblast (CTB) progenitors of a first-trimester human placenta. We also show that a subset of unexplained recurrent pregnancy losses (idiopathic RPLs) is associated with impaired TEAD4 expression in CTB progenitors. Furthermore, by establishing idiopathic RPL patient-specific human trophoblast stem cells (RPL-TSCs), we show that loss of TEAD4 is associated with defective self-renewal in RPL-TSCs and rescue of TEAD4 expression restores their self-renewal ability. Unbiased genomics studies revealed that TEAD4 directly regulates expression of key cell cycle genes in both mouse and human TSCs and establishes a conserved transcriptional program. Our findings show that TEAD4, an effector of the Hippo signaling pathway, is essential for the establishment of pregnancy in a postimplantation mammalian embryo and indicate that impairment of the Hippo signaling pathway could be a molecular cause for early human pregnancy loss.


Assuntos
Autorrenovação Celular/genética , Proteínas de Ligação a DNA/genética , Desenvolvimento Embrionário/genética , Proteínas Musculares/genética , Fatores de Transcrição/genética , Trofoblastos/citologia , Trofoblastos/metabolismo , Aborto Habitual/etiologia , Aborto Habitual/metabolismo , Aborto Espontâneo/etiologia , Aborto Espontâneo/metabolismo , Animais , Biomarcadores , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Implantação do Embrião , Feminino , Imunofluorescência , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Imuno-Histoquímica , Camundongos , Proteínas Musculares/metabolismo , Placenta/metabolismo , Gravidez , Fatores de Transcrição/metabolismo
8.
PLoS One ; 15(6): e0234913, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32574189

RESUMO

The transcriptional regulatory machinery in mitochondrial bioenergetics is complex and is still not completely understood. We previously demonstrated that the histone methyltransferase Smyd1 regulates mitochondrial energetics. Here, we identified Perm1 (PPARGC-1 and ESRR-induced regulator, muscle specific 1) as a downstream target of Smyd1 through RNA-seq. Chromatin immunoprecipitation assay showed that Smyd1 directly interacts with the promoter of Perm1 in the mouse heart, and this interaction was significantly reduced in mouse hearts failing due to pressure overload for 4 weeks, where Perm1 was downregulated (24.4 ± 5.9% of sham, p<0.05). Similarly, the Perm1 protein level was significantly decreased in patients with advanced heart failure (55.2 ± 13.1% of donors, p<0.05). Phenylephrine (PE)-induced hypertrophic stress in cardiomyocytes also led to downregulation of Perm1 (55.7 ± 5.7% of control, p<0.05), and adenovirus-mediated overexpression of Perm1 rescued PE-induced downregulation of estrogen-related receptor alpha (ERRα), a key transcriptional regulator of mitochondrial energetics, and its target gene, Ndufv1 (Complex I). Pathway enrichment analysis of cardiomyocytes in which Perm1 was knocked-down by siRNA (siPerm1), revealed that the most downregulated pathway was metabolism. Cell stress tests using the Seahorse XF analyzer showed that basal respiration and ATP production were significantly reduced in siPerm1 cardiomyocytes (40.7% and 23.6% of scrambled-siRNA, respectively, both p<0.05). Luciferase reporter gene assay further revealed that Perm1 dose-dependently increased the promoter activity of the ERRα gene and known target of ERRα, Ndufv1 (Complex I). Overall, our study demonstrates that Perm1 is an essential regulator of cardiac energetics through ERRα, as part of the Smyd1 regulatory network.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas Musculares/metabolismo , Miocárdio/metabolismo , Fatores de Transcrição/metabolismo , Adulto , Idoso , Animais , Metilação de DNA , Modelos Animais de Doenças , Regulação para Baixo , Complexo I de Transporte de Elétrons/genética , Metabolismo Energético/genética , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/cirurgia , Transplante de Coração , Histonas/genética , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Musculares/genética , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fosforilação Oxidativa , Fenilefrina/farmacologia , Cultura Primária de Células , Regiões Promotoras Genéticas/genética , RNA Interferente Pequeno/metabolismo , RNA-Seq , Ratos , Receptores Estrogênicos/genética
9.
Am Heart J ; 225: 108-119, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32480058

RESUMO

INTRODUCTION: Biallelic damaging variants in ALPK3, encoding alpha-protein kinase 3, cause pediatric-onset cardiomyopathy with manifestations that are incompletely defined. METHODS AND RESULTS: We analyzed clinical manifestations of damaging biallelic ALPK3 variants in 19 pediatric patients, including nine previously published cases. Among these, 11 loss-of-function (LoF) variants, seven compound LoF and deleterious missense variants, and one homozygous deleterious missense variant were identified. Among 18 live-born patients, 8 exhibited neonatal dilated cardiomyopathy (44.4%; 95% CI: 21.5%-69.2%) that subsequently transitioned into ventricular hypertrophy. The majority of patients had extracardiac phenotypes, including contractures, scoliosis, cleft palate, and facial dysmorphisms. We observed no association between variant type or location, disease severity, and/or extracardiac manifestations. Myocardial histopathology showed focal cardiomyocyte hypertrophy, subendocardial fibroelastosis in patients under 4 years of age, and myofibrillar disarray in adults. Rare heterozygous ALPK3 variants were also assessed in adult-onset cardiomyopathy patients. Among 1548 Dutch patients referred for initial genetic analyses, we identified 39 individuals with rare heterozygous ALPK3 variants (2.5%; 95% CI: 1.8%-3.4%), including 26 missense and 10 LoF variants. Among 149 U.S. patients without pathogenic variants in 83 cardiomyopathy-related genes, we identified six missense and nine LoF ALPK3 variants (10.1%; 95% CI: 5.7%-16.1%). LoF ALPK3 variants were increased in comparison to matched controls (Dutch cohort, P = 1.6×10-5; U.S. cohort, P = 2.2×10-13). CONCLUSION: Biallelic damaging ALPK3 variants cause pediatric cardiomyopathy manifested by DCM transitioning to hypertrophy, often with poor contractile function. Additional extracardiac features occur in most patients, including musculoskeletal abnormalities and cleft palate. Heterozygous LoF ALPK3 variants are enriched in adults with cardiomyopathy and may contribute to their cardiomyopathy. Adults with ALPK3 LoF variants therefore warrant evaluations for cardiomyopathy.


Assuntos
Cardiomiopatias/genética , Heterozigoto , Mutação com Perda de Função , Proteínas Musculares/genética , Mutação de Sentido Incorreto , Proteínas Quinases/genética , Anormalidades Múltiplas/genética , Adulto , Idade de Início , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/fisiopatologia , Cardiomiopatia Dilatada/genética , Cardiomiopatia Hipertrófica/genética , Criança , Pré-Escolar , Cromossomos Humanos Par 15/genética , Ecocardiografia , Eletrocardiografia , Humanos , Lactente , Fenótipo
10.
Dev Genes Evol ; 230(4): 265-278, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32556563

RESUMO

hlh-1 is a myogenic transcription factor required for body-wall muscle specification during embryogenesis in Caenorhabditis elegans. Despite its well-known role in muscle specification, comprehensive regulatory control upstream of hlh-1 remains poorly defined. Here, we first established a statistical reference for the spatiotemporal expression of hlh-1 at single-cell resolution up to the second last round of divisions for most of the cell lineages (from 4- to 350-cell stage) using 13 wild-type embryos. We next generated lineal expression of hlh-1 after RNA interference (RNAi) perturbation of 65 genes, which were selected based on their degree of conservation, mutant phenotypes, and known roles in development. We then compared the expression profiles between wild-type and RNAi embryos by clustering according to their lineal expression patterns using mean-shift and density-based clustering algorithms, which not only confirmed the roles of existing genes but also uncovered the potential functions of novel genes in muscle specification at multiple levels, including cellular, lineal, and embryonic levels. By combining the public data on protein-protein interactions, protein-DNA interactions, and genetic interactions with our RNAi data, we inferred regulatory pathways upstream of hlh-1 that function globally or locally. This work not only revealed diverse and multilevel regulatory mechanisms coordinating muscle differentiation during C. elegans embryogenesis but also laid a foundation for further characterizing the regulatory pathways controlling muscle specification at the cellular, lineal (local), or embryonic (global) level.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/metabolismo , Desenvolvimento Muscular/genética , Proteínas Musculares/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Linhagem da Célula/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Família Multigênica , Proteínas Musculares/genética , Proteínas Nucleares/genética , Fenótipo , Interferência de RNA , Transdução de Sinais/genética , Análise de Célula Única , Fatores de Transcrição/genética
11.
Nat Cell Biol ; 22(7): 803-814, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32572169

RESUMO

Cell shape is controlled by the submembranous cortex, an actomyosin network mainly generated by two actin nucleators: the Arp2/3 complex and the formin mDia1. Changes in relative nucleator activity may alter cortical organization, mechanics and cell shape. Here we investigate how nucleation-promoting factors mediate interactions between nucleators. In vitro, the nucleation-promoting factor SPIN90 promotes formation of unbranched filaments by Arp2/3, a process thought to provide the initial filament for generation of dendritic networks. Paradoxically, in cells, SPIN90 appears to favour a formin-dominated cortex. Our in vitro experiments reveal that this feature stems mainly from two mechanisms: efficient recruitment of mDia1 to SPIN90-Arp2/3 nucleated filaments and formation of a ternary SPIN90-Arp2/3-mDia1 complex that greatly enhances filament nucleation. Both mechanisms yield rapidly elongating filaments with mDia1 at their barbed ends and SPIN90-Arp2/3 at their pointed ends. Thus, in networks, SPIN90 lowers branching densities and increases the proportion of long filaments elongated by mDia1.


Assuntos
Citoesqueleto de Actina/fisiologia , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Forminas/metabolismo , Melanoma/patologia , Proteínas Musculares/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Blástula/citologia , Blástula/metabolismo , Forma Celular , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Forminas/genética , Humanos , Melanoma/genética , Melanoma/metabolismo , Proteínas Musculares/genética , Xenopus laevis/crescimento & desenvolvimento , Xenopus laevis/metabolismo
12.
Proc Natl Acad Sci U S A ; 117(24): 13562-13570, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32482863

RESUMO

Various pregnancy complications, such as severe forms of preeclampsia or intrauterine growth restriction, are thought to arise from failures in the differentiation of human placental trophoblasts. Progenitors of the latter either develop into invasive extravillous trophoblasts, remodeling the uterine vasculature, or fuse into multinuclear syncytiotrophoblasts transporting oxygen and nutrients to the growing fetus. However, key regulatory factors controlling trophoblast self-renewal and differentiation have been poorly elucidated. Using primary cells, three-dimensional organoids, and CRISPR-Cas9 genome-edited JEG-3 clones, we herein show that YAP, the transcriptional coactivator of the Hippo signaling pathway, promotes maintenance of cytotrophoblast progenitors by different genomic mechanisms. Genetic or chemical manipulation of YAP in these cellular models revealed that it stimulates proliferation and expression of cell cycle regulators and stemness-associated genes, but inhibits cell fusion and production of syncytiotrophoblast (STB)-specific proteins, such as hCG and GDF15. Genome-wide comparisons of primary villous cytotrophoblasts overexpressing constitutively active YAP-5SA with YAP KO cells and syncytializing trophoblasts revealed common target genes involved in trophoblast stemness and differentiation. ChIP-qPCR unraveled that YAP-5SA overexpression increased binding of YAP-TEAD4 complexes to promoters of proliferation-associated genes such as CCNA and CDK6 Moreover, repressive YAP-TEAD4 complexes containing the histone methyltransferase EZH2 were detected in the genomic regions of the STB-specific CGB5 and CGB7 genes. In summary, YAP plays a pivotal role in the maintenance of the human placental trophoblast epithelium. Besides activating stemness factors, it also directly represses genes promoting trophoblast cell fusion.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Placentação , Fatores de Transcrição/metabolismo , Trofoblastos/citologia , Trofoblastos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Diferenciação Celular , Proliferação de Células , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Placenta/metabolismo , Gravidez , Ligação Proteica , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/genética
13.
Nat Commun ; 11(1): 2699, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483185

RESUMO

Nebulin is a giant protein that winds around the actin filaments in the skeletal muscle sarcomere. Compound-heterozygous mutations in the nebulin gene (NEB) cause typical nemaline myopathy (NM), a muscle disorder characterized by muscle weakness with limited treatment options. We created a mouse model with a missense mutation p.Ser6366Ile and a deletion of NEB exon 55, the Compound-Het model that resembles typical NM. We show that Compound-Het mice are growth-retarded and have muscle weakness. Muscles have a reduced myofibrillar fractional-area and sarcomeres are disorganized, contain rod bodies, and have longer thin filaments. In contrast to nebulin-based severe NM where haplo-insufficiency is the disease driver, Compound-Het mice express normal amounts of nebulin. X-ray diffraction revealed that the actin filament is twisted with a larger radius, that tropomyosin and troponin behavior is altered, and that the myofilament spacing is increased. The unique disease mechanism of nebulin-based typical NM reveals novel therapeutic targets.


Assuntos
Proteínas Musculares/genética , Mutação de Sentido Incorreto , Miofibrilas/metabolismo , Miopatias da Nemalina/genética , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Animais , Heterozigoto , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Miofibrilas/patologia , Miofibrilas/ultraestrutura , Miopatias da Nemalina/metabolismo , Sarcômeros/metabolismo , Sarcômeros/patologia , Sarcômeros/ultraestrutura , Tropomiosina/química , Tropomiosina/metabolismo , Troponina/química , Troponina/metabolismo , Difração de Raios X
14.
Gene ; 750: 144723, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32387119

RESUMO

The BCL2L12, one of the latest discovered members of the BCL2 family, has both pro- and anti-apoptotic roles that are cell-type-dependent. Its role in tumorigenesis is highly implicated. Sixty-three splice variants of this gene have been identified so far, with significant differences in expression patterns between various cancer cell lines. Presently, little is known regarding the regulation of expression of the BCL2L12 gene. For the vast majority of BCL2L12 gene splice variants, the 5'- and 3'-untranslated regions as well as their transcriptional regulation have not been determined yet. The aim of this study was to get insight into the regulation of the BCL2L12 gene transcription in human chronic myelogenous leukemia (K562) cell line. Our results point to the activity of novel transcription start site of the BCL2L12 gene and indicate that Sp1 and GATA-1 transcription factors could be involved in the regulation of BCL2L12 gene expression in K562 cells. The previously reported active promoter of BCL2L12 gene differs from the one we described in our study. If this novel BCL2L12 promoter is confirmed to be active in other malignancies, transcripts generated from this region could be considered as new cancer-specific biomarkers. The results of our study contribute to the better understanding of the transcriptional regulation of the BCL2L12 gene.


Assuntos
Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose/fisiologia , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Expressão Gênica , Humanos , Células K562 , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sítio de Iniciação de Transcrição , Transcrição Genética
15.
Nat Commun ; 11(1): 2186, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32367034

RESUMO

Diabetic cardiomyopathy is a progressive disease in diabetic patients, and myocardial insulin resistance contributes to its pathogenesis through incompletely-defined mechanisms. Striated muscle preferentially expressed protein kinase (SPEG) has two kinase-domains and is a critical cardiac regulator. Here we show that SPEG is phosphorylated on Ser2461/Ser2462/Thr2463 by protein kinase B (PKB) in response to insulin. PKB-mediated phosphorylation of SPEG activates its second kinase-domain, which in turn phosphorylates sarcoplasmic/endoplasmic reticulum calcium-ATPase 2a (SERCA2a) and accelerates calcium re-uptake into the SR. Cardiac-specific deletion of PKBα/ß or a high fat diet inhibits insulin-induced phosphorylation of SPEG and SERCA2a, prolongs SR re-uptake of calcium, and impairs cardiac function. Mice bearing a Speg3A mutation to prevent its phosphorylation by PKB display cardiac dysfunction. Importantly, the Speg3A mutation impairs SERCA2a phosphorylation and calcium re-uptake into the SR. Collectively, these data demonstrate that insulin resistance impairs this PKB-SPEG-SERCA2a signal axis, which contributes to the development of diabetic cardiomyopathy.


Assuntos
Cálcio/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Homeostase , Resistência à Insulina , Proteínas Musculares/metabolismo , Quinase de Cadeia Leve de Miosina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Cardiomiopatias Diabéticas/genética , Humanos , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Insulina/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Musculares/genética , Mutação , Quinase de Cadeia Leve de Miosina/genética , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/genética , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Transdução de Sinais/genética
16.
Toxicol Lett ; 327: 19-31, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32234357

RESUMO

Traditional Chinese Medicines (TCMs)-containing aconitine are popular and indispensable home remedies in Asia for thousands of years due to its excellent pharmaceutical effects. Accumulating evidence has identified that repeated-dose of aconitine could cause polymorphic ventricular arrhythmias. However, underlying molecular mechanisms are still not fully understood. Hence, the present study firstly investigated the potential role of Notch1 signaling in aconitine-induced cardiotoxicity, aiming to elaborate possible molecular mechanisms involved in aconitine triggered ventricular arrhythmias. Our results showed that aconitine increased Notch1 signaling and downstream KDM5A expression in human and rat cardiomyocytes at non-detectable cytotoxic doses. Furthermore, aconitine promoted the formation of a new regulatory complex containing NICD and KDM5A in a CK2αHI regime, which then targeted to HCN4 promoter and induced re-expression of HCN4 in mature cardiomyocytes. Ultimately, HCN4-mediated If current contributed to aconitine-caused alterations in beating rate of rat cardiomyocytes. All changes aforementioned were significantly ameliorated by Notch1 inhibitor, suggesting that Notch1-mediated epigenetic regulation of HCN4 contributes to aconitine-induced ventricular myocardial dysrhythmia. Thus, our findings provide a novel toxic mechanism and position Notch1/NICD/KDM5A/HCN4 toxicity pathway as a potential target for the treatments of repeated-dose of medicine containing aconitine induced ventricular arrhythmias.


Assuntos
Aconitina/farmacologia , Arritmias Cardíacas/induzido quimicamente , Ventrículos do Coração/efeitos dos fármacos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Canais de Potássio/metabolismo , Receptor Notch1/metabolismo , Animais , Animais Recém-Nascidos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Canais de Potássio/genética , Ratos , Receptor Notch1/genética , Superóxidos/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-32233951

RESUMO

Intraflagellar transport (IFT) is an evolutionarily conserved mechanism that is indispensable for the formation and maintenance of cilia and flagella; however, the implications and functions of IFT81 remain unknown. In this study, we disrupted IFT81 expression in male germ cells starting from the spermatocyte stage. As a result, homozygous mutant males were completely infertile and displayed abnormal sperm parameters. In addition to oligozoospermia, spermatozoa presented dysmorphic and nonfunctional flagella. Histological examination of testes from homozygous mutant mice revealed abnormal spermiogenesis associated with sloughing of germ cells and the presence of numerous multinucleated giant germ cells (symblasts) in the lumen of seminiferous tubules and epididymis. Moreover, only few elongated spermatids and spermatozoa were seen in analyzed cross sections. Transmission electron microscopy showed a complete disorganization of the axoneme and para-axonemal structures such as the mitochondrial sheath, fibrous sheath, and outer dense fibers. In addition, numerous vesicles that contain unassembled microtubules were observed within developing spermatids. Acrosome structure analysis showed normal appearance, thus excluding a crucial role of IFT81 in acrosome biogenesis. These observations showed that IFT81 is an important member of the IFT process during spermatogenesis and that its absence is associated with abnormal flagellum formation leading to male infertility. The expression levels of several IFT components in testes, including IFT20, IFT25, IFT27, IFT57, IFT74, and IFT88, but not IFT140, were significantly reduced in homozygous mutant mice. Overall, our study demonstrates that IFT81 plays an essential role during spermatogenesis by modulating the assembly and elongation of the sperm flagella.


Assuntos
Fertilidade , Flagelos/metabolismo , Infertilidade Masculina/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Musculares/metabolismo , Espermatócitos/metabolismo , Espermatogênese , Testículo/metabolismo , Animais , Proteínas do Citoesqueleto/metabolismo , Epididimo/metabolismo , Epididimo/fisiopatologia , Epididimo/ultraestrutura , Flagelos/ultraestrutura , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/deficiência , Proteínas Associadas aos Microtúbulos/genética , Proteínas Musculares/deficiência , Proteínas Musculares/genética , Transdução de Sinais , Contagem de Espermatozoides , Motilidade Espermática , Espermatócitos/ultraestrutura , Testículo/fisiopatologia , Testículo/ultraestrutura
18.
J Clin Neurosci ; 75: 195-198, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32238315

RESUMO

Congenital myasthenic syndromes (CMS) associated with pathogenic variants in the DOK7 gene (DOK7-CMS) have phenotypic overlap with other neuromuscular disorders associated with limb-girdle muscular weakness (LGMW). Genetic analysis of the most common mutation (c.1124_1127dupTGCC) in DOK7 was performed in 34 patients with "unexplained" LGMW associated with non-specific changes in muscle biopsy. Of the 34 patients, one patient showed the DOK7 c.1124_1127dupTGCC variant in homozygousity. Our study estimates the minimum prevalence of undiagnosed DOK7-CMS to be 2.9% in southern Brazilian patients from our centre. Our data confirm that clinicians should look for DOK7-CMS patients when the clinical manifestation is an 'unexplained' LGMW, mainly if associated with non-specific changes in muscle biopsy.


Assuntos
Proteínas Musculares/genética , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação/genética , Síndromes Miastênicas Congênitas/diagnóstico , Síndromes Miastênicas Congênitas/genética , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Estudos de Coortes , Feminino , Testes Genéticos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/diagnóstico , Debilidade Muscular/epidemiologia , Debilidade Muscular/genética , Distrofia Muscular do Cíngulo dos Membros/epidemiologia , Síndromes Miastênicas Congênitas/epidemiologia , Estudos Retrospectivos , Adulto Jovem
19.
J Anim Sci ; 98(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32249920

RESUMO

Smooth muscle cells (SMCs) play an important role in physiology and production in farm animals such as pigs. Here, we report the generation of a pig SMC line. Our original objective was to establish an enteroendocrine cell line from the pig ileum epithelium through lentiviral transduction of the Simian Virus (SV) 40 large T antigen. However, an initial expression analysis of marker genes in nine cell clones revealed that none of them were enteroendocrine cells or absorptive enterocytes, goblet cells, or Paneth cells, some of the major cell types existing in the ileum epithelium. A more detailed characterization of one clone named PIC7 by RNA-seq showed that these cells expressed many of the known smooth muscle-specific or -enriched genes, including smooth muscle actin alpha 2, calponin 1, calponin 3, myosin heavy chain 11, myosin light chain kinase, smoothelin, tenascin C, transgelin, tropomyosin 1, and tropomyosin 2. Both quantitative PCR and RNA-seq analyses showed that the PIC7 cells had a high expression of mRNA for smooth muscle actin gamma 2, also known as enteric smooth muscle actin. A Western blot analysis confirmed the expression of SV40 T antigen in the PIC7 cells. An immunohistochemical analysis demonstrated the expression of smooth muscle actin alpha 2 filaments in the PIC7 cells. A collagen gel contraction assay showed that the PIC7 cells were capable of both spontaneous contraction and contraction in response to serotonin stimulation. We conclude that the PIC7 cells are derived from an enteric SMC from the pig ileum. These cells may be a useful model for studying the cellular and molecular physiology of pig enteric SMCs. Because pigs are similar to humans in anatomy and physiology, the PIC7 cells may be also used as a model for human intestinal SMCs.


Assuntos
Suínos/fisiologia , Actinas/genética , Animais , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular , Íleo/fisiologia , Proteínas dos Microfilamentos/genética , Proteínas Musculares/genética , Músculo Liso/fisiologia , Miócitos de Músculo Liso/fisiologia , Miosinas/genética , Especificidade de Órgãos , RNA Mensageiro/genética , Suínos/genética , Tenascina/genética , Tropomiosina/genética
20.
Neoplasma ; 67(3): 461-472, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32122140

RESUMO

Oral cancer is one of the common cancers worldwide, among which over 90% are oral squamous cell carcinomas (OSCC). MicroRNAs act as critical regulators of cancer development and progression. MiR-103a-3p has been reported to be upregulated in OSCC patients and closely correlated to poor prognosis, yet its roles in the progression of OSCC remain undisclosed. In this study, we knocked down the expression of miR-103a-3p in two OSCC cell lines in vitro, and significantly repressed cell proliferation and cell cycle arrest at the G1 phase were observed, accompanied by decreased proliferating cell nuclear antigen, cyclin D1, cyclin B1 and increased PTEN levels. MiR-103a-3p inhibition also induced apoptosis as evidenced by increased apoptotic cells and upregulated cleaved caspase-9/casapase-3 expression. We established a xenograft model in nude mice and found that miR-103a-3p knockdown also suppressed tumor growth in vivo. Besides, the expression of regulator of calcineurin1 (RCAN1), known as its anti-tumor effect, was negatively correlated with the miR-103a-3p level in OSCC cells. We validated that RCAN1 was a downstream target of miR-103a-3p using the dual-luciferase assay. RCAN1 silencing reversed the cell proliferative inhibition, cell cycle arrest and cell apoptosis induced by miR-103a-3p knockdown. In addition, we found that long non-coding RNA LINC00675 acted as a sponge of miR-103a-3p and promoted the expression of miR-103a-3p targets RCAN1 and PTEN. In summary, miR-103a-3p inhibition represses proliferation and induces apoptosis of OSCC cells through regulating RCAN1, and miR-103a-3p may act as a novel diagnostic marker and therapeutic target for OSCC.


Assuntos
Carcinoma de Células Escamosas/patologia , Proteínas de Ligação a DNA/genética , MicroRNAs/genética , Neoplasias Bucais/patologia , Proteínas Musculares/genética , Animais , Apoptose , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Proliferação de Células , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos , Camundongos , Camundongos Nus , Neoplasias Bucais/genética
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