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1.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1445-1450, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067935

RESUMO

OBJECTIVE: To study the molecular characteristics and clinical significance of elderly patients with acute myeloid leukemia (AML). METHODS: Dideoxy sequencing was used to analyze the mutation spectrum and clinical significance of 51 hematopathy-related genes in 52 patients with newly diagnosed elderly AML. The efficacy of 39 patients receiving DCAG chemotherapy was also analyzed. RESULTS: The mutational frequency was high in elderly AML patients (98.1%, 51/52), and there were some coexistence or mutual exclusion between different mutations. Both the number of mutations and the incidence of epigenetic mutations DNMT3A, TET2 (P<0.01), as well as FLT3-ITD (P<0.05) increased with age. c-KIT mutations were most common in favorable-risk AML (P<0.01), while NPM1 and DNMT3A were common in intermediate-risk AML (P<0.05), especially in AML with normal karyotype. The complete remission rate of elderly AML patients receiving DCAG chemotherapy was 71.8% (28/39). CONCLUSION: Elderly AML patients have specific molecular characteristics, and the incidence of methylation-related gene mutations is very high, showing a certain significance for clinical diagnosis and treatment.


Assuntos
Leucemia Mieloide Aguda , Proteínas Nucleares , Idoso , Humanos , Leucemia Mieloide Aguda/genética , Mutação , Taxa de Mutação , Proteínas Nucleares/genética , Prognóstico
2.
Nat Commun ; 11(1): 4869, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978394

RESUMO

Poly(ADP-ribosyl)ation is a reversible post-translational modification synthetized by ADP-ribose transferases and removed by poly(ADP-ribose) glycohydrolase (PARG), which plays important roles in DNA damage repair. While well-studied in somatic tissues, much less is known about poly(ADP-ribosyl)ation in the germline, where DNA double-strand breaks are introduced by a regulated program and repaired by crossover recombination to establish a tether between homologous chromosomes. The interaction between the parental chromosomes is facilitated by meiotic specific adaptation of the chromosome axes and cohesins, and reinforced by the synaptonemal complex. Here, we uncover an unexpected role for PARG in coordinating the induction of meiotic DNA breaks and their homologous recombination-mediated repair in Caenorhabditis elegans. PARG-1/PARG interacts with both axial and central elements of the synaptonemal complex, REC-8/Rec8 and the MRN/X complex. PARG-1 shapes the recombination landscape and reinforces the tightly regulated control of crossover numbers without requiring its catalytic activity. We unravel roles in regulating meiosis, beyond its enzymatic activity in poly(ADP-ribose) catabolism.


Assuntos
Caenorhabditis elegans/metabolismo , Quebras de DNA de Cadeia Dupla , Reparo do DNA/fisiologia , DNA/metabolismo , Glicosídeo Hidrolases/metabolismo , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Núcleo Celular/metabolismo , Células Germinativas , Glicosídeo Hidrolases/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Poli ADP Ribosilação , Poli Adenosina Difosfato Ribose/metabolismo , Processamento de Proteína Pós-Traducional
3.
Sci Immunol ; 5(51)2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887845

RESUMO

A novel role for SWI/SNF complexes in tuning Foxp3 expression and activity in Tregs.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Nucleossomos , Proteínas Nucleares/genética , Linfócitos T Reguladores , Fatores de Transcrição/genética
4.
Clin Imaging ; 67: 198-206, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32866821

RESUMO

Nuclear protein of the testis (NUT) carcinoma (NC) (formerly known as NUT midline carcinoma) is an aggressive pleomorphic squamous cell carcinoma with a dismal prognosis. Primary NC tumors are commonly located in the chest or head and neck regions. Imaging plays an indispensable role in the staging, management, treatment response assessment, and surveillance of NC. Primary pulmonary NC usually presents as a large mass with lymphadenopathy and pleural involvement. Primary head and neck NC presents as a large expansile necrotic mass in the sinonasal region with locoregional destruction and occasional cervical lymph node involvement. These imaging features are relatively non-specific but are consistent among patients. Currently, there are no standardized guidelines for the treatment of NC. Because of its rarity, paucity of reports in the medical literature, and the lack of awareness among radiologists, NUT carcinoma (NC) has been largely underdiagnosed and misdiagnosed. Clinical aggressive features and pleomorphic/undifferentiated squamous cell carcinoma should prompt genetic evaluation for NUT translocation to diagnose NC. In this article, we discuss NC's clinicopathologic and imaging features and treatment options, including emerging new treatments.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias Testiculares/diagnóstico por imagem , Testículo/diagnóstico por imagem , Adulto , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço , Humanos , Neoplasias Pulmonares/genética , Masculino , Pescoço/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo
5.
Medicine (Baltimore) ; 99(33): e21632, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32872024

RESUMO

INTRODUCTION: The oligophrenin-1 (OPHN1) gene, localized on the X chromosome, is a Rho-GTPase activating protein that is related to syndromic X-linked intellectual disability (XLID). XLID, characterized by brain anomalies, namely cerebellar hypoplasia, specific facial features, and intellectual disability, is produced by different mutations in the OPHN1 gene. PATIENT CONCERNS: In this report, we present the clinical and molecular findings of a family affected by a mild XLID due to a deletion in the OPHN1 gene, exon 21, Xq12 region using Multiplex Ligation-dependent Probe Amplification (MLPA) analysis. The clinical features present in the family are a mild developmental delay, behavioral disturbances, facial dysmorphism, pes planus, nystagmus, strabismus, epilepsy, and occipital arachnoid cyst. INTERVENTIONS: The MLPA analysis was performed for investigation of the copy number variations within the X chromosome for the family. DIAGNOSIS AND OUTCOME: The MLPA analysis detected a deletion in the OPHN1 gene, exon 21 for the proband, and a heterozygous deletion for the probands mother. The deletion of the Xq12 region of maternal origin, including the exon 21 of the OPHN1 gene, confirmed for the probands nephew. LESSONS: Our findings emphasize the utility of the MLPA analysis to identify deletions in the OPHN1 gene responsible for syndromic XLID. Therefore, we suggest that MLPA analysis should be performed as an alternative diagnostic test for all patients with a mild intellectual disability associated or not with behavioral disturbances, facial dysmorphism, and brain anomalies.


Assuntos
Proteínas do Citoesqueleto/genética , Proteínas Ativadoras de GTPase/genética , Deficiência Intelectual/genética , Proteínas Nucleares/genética , Adolescente , Éxons , Deleção de Genes , Humanos , Masculino
6.
Nat Commun ; 11(1): 4653, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938923

RESUMO

Cancer cells demand excess nutrients to support their proliferation, but how tumours exploit extracellular amino acids during systemic metabolic perturbations remain incompletely understood. Here, we use a Drosophila model of high-sugar diet (HSD)-enhanced tumourigenesis to uncover a systemic host-tumour metabolic circuit that supports tumour growth. We demonstrate coordinate induction of systemic muscle wasting with tumour-autonomous Yorkie-mediated SLC36-family amino acid transporter expression as a proline-scavenging programme to drive tumourigenesis. We identify Indole-3-propionic acid as an optimal amino acid derivative to rationally target the proline-dependency of tumour growth. Insights from this whole-animal Drosophila model provide a powerful approach towards the identification and therapeutic exploitation of the amino acid vulnerabilities of tumourigenesis in the context of a perturbed systemic metabolic network.


Assuntos
Açúcares da Dieta/efeitos adversos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Neoplasias Experimentais/fisiopatologia , Prolina/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Animais , Animais Geneticamente Modificados , Carcinogênese , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Larva , Debilidade Muscular/induzido quimicamente , Debilidade Muscular/patologia , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/patologia , Neoplasias Experimentais/etiologia , Proteínas Nucleares/genética , Receptores Proteína Tirosina Quinases/metabolismo , Transativadores/genética , Proteínas ras/genética
7.
Nat Commun ; 11(1): 4666, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938943

RESUMO

Intercalated discs (ICD), specific cell-to-cell contacts that connect adjacent cardiomyocytes, ensure mechanical and electrochemical coupling during contraction of the heart. Mutations in genes encoding ICD components are linked to cardiovascular diseases. Here, we show that loss of Xinß, a newly-identified component of ICDs, results in cardiomyocyte proliferation defects and cardiomyopathy. We uncovered a role for Xinß in signaling via the Hippo-YAP pathway by recruiting NF2 to the ICD to modulate cardiac function. In Xinß mutant hearts levels of phosphorylated NF2 are substantially reduced, suggesting an impairment of Hippo-YAP signaling. Cardiac-specific overexpression of YAP rescues cardiac defects in Xinß knock-out mice-indicating a functional and genetic interaction between Xinß and YAP. Our study reveals a molecular mechanism by which cardiac-expressed intercalated disc protein Xinß modulates Hippo-YAP signaling to control heart development and cardiac function in a tissue specific manner. Consequently, this pathway may represent a therapeutic target for the treatment of cardiovascular diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas com Domínio LIM/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Cardiomiopatia Dilatada/genética , Comunicação Celular , Proteínas de Ciclo Celular/genética , Proliferação de Células , Proteínas do Citoesqueleto/genética , Proteínas de Ligação a DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Ventrículos do Coração/crescimento & desenvolvimento , Proteínas com Domínio LIM/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Miócitos Cardíacos/citologia , Miócitos Cardíacos/patologia , Neurofibromina 2/genética , Neurofibromina 2/metabolismo , Proteínas Nucleares/genética , Transdução de Sinais
8.
PLoS One ; 15(9): e0238477, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32877461

RESUMO

Somatic copy number alterations (CNA) are common in endometrial serous carcinoma (ESC). We used the Tumor Cancer Genome Atlas Pan Cancer dataset (TCGA Pan Can) to explore the impact of somatic CNA and gene expression levels (mRNA) of cancer-related genes in ESC. Results were correlated with clinico-pathologic parameters such as age of onset, disease stage, progression-free survival (PFS) and overall survival (OS) (n = 108). 1,449 genes with recurrent somatic CNA were identified, observed in 10% or more tumor samples. Somatic CNA and mRNA expression levels were highly correlated (r> = 0.6) for 383 genes. Among these, 45 genes were classified in the Tier 1 category of Cancer Genome Census-Catalogue of Somatic Mutations in Cancer. Eighteen of 45 Tier 1 genes had highly correlated somatic CNA and mRNA expression levels including ARNT, PIK3CA, TBLXR1, ASXL1, EIF4A2, HOOK3, IKBKB, KAT6A, TCEA1, KAT6B, ERBB2, BRD4, KEAP1, PRKACA, DNM2, SMARCA4, AKT2, SS18L1. Our results are in agreement with previously reported somatic CNA for ERBB2, BRD4 and PIK3C in ESC. In addition, AKT2 (p = 0.002) and KAT6A (p = 0.015) amplifications were more frequent in tumor samples from younger patients (<60), and CEBPA (p = 0.028) and MYC (p = 0.023) amplifications were more common with advanced (stage III and IV) disease stage. Patients with tumors carrying KAT6A and MYC amplifications had shorter PFS and OS. The hazard ratio (HR) of KAT6A was 2.82 [95 CI 1.12-7.07] for PFS and 3.87 [95 CI 1.28-11.68] for OS. The HR of MYC was 2.25 [95 CI 1.05-4.81] and 2.62[95 CI 1.07-6.41] for PFS and OS, respectively.


Assuntos
Neoplasias do Endométrio/genética , Histona Acetiltransferases/genética , Biomarcadores Tumorais/genética , Classe I de Fosfatidilinositol 3-Quinases , Cistadenocarcinoma Seroso/genética , Variações do Número de Cópias de DNA/genética , DNA Helicases , Bases de Dados Genéticas , Intervalo Livre de Doença , Neoplasias do Endométrio/patologia , Feminino , Perfilação da Expressão Gênica/métodos , Histona Acetiltransferases/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch , Mutação , Fator 2 Relacionado a NF-E2 , Proteínas Nucleares/genética , Oncogenes , Neoplasias Ovarianas/patologia , Prognóstico , Intervalo Livre de Progressão , Fatores de Transcrição , Transcriptoma/genética
9.
PLoS Pathog ; 16(8): e1008752, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760121

RESUMO

Members of the family of pyrin and HIN domain containing (PYHIN) proteins play an emerging role in innate immunity. While absent in melanoma 2 (AIM2) acts a cytosolic sensor of non-self DNA and plays a key role in inflammasome assembly, the γ-interferon-inducible protein 16 (IFI16) restricts retroviral gene expression by sequestering the transcription factor Sp1. Here, we show that the remaining two human PYHIN proteins, i.e. myeloid cell nuclear differentiation antigen (MNDA) and pyrin and HIN domain family member 1 (PYHIN1 or IFIX) share this antiretroviral function of IFI16. On average, knock-down of each of these three nuclear PYHIN proteins increased infectious HIV-1 yield from human macrophages by more than an order of magnitude. Similarly, knock-down of IFI16 strongly increased virus transcription and production in primary CD4+ T cells. The N-terminal pyrin domain (PYD) plus linker region containing a nuclear localization signal (NLS) were generally required and sufficient for Sp1 sequestration and anti-HIV-1 activity of IFI16, MNDA and PYHIN1. Replacement of the linker region of AIM2 by the NLS-containing linker of IFI16 resulted in a predominantly nuclear localization and conferred direct antiviral activity to AIM2 while attenuating its ability to form inflammasomes. The reverse change caused nuclear-to-cytoplasmic relocalization of IFI16 and impaired its antiretroviral activity but did not result in inflammasome assembly. We further show that the Zn-finger domain of Sp1 is critical for the interaction with IFI16 supporting that pyrin domains compete with DNA for Sp1 binding. Finally, we found that human PYHIN proteins also inhibit Hepatitis B virus and simian vacuolating virus 40 as well as the LINE-1 retrotransposon. Altogether, our data show that IFI16, PYHIN1 and MNDA restrict HIV-1 and other viral pathogens by interfering with Sp1-dependent gene expression and support an important role of nuclear PYHIN proteins in innate antiviral immunity.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Núcleo Celular/metabolismo , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Macrófagos/imunologia , Proteínas Nucleares/metabolismo , Fator de Transcrição Sp1/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Núcleo Celular/genética , DNA Viral/genética , Células HEK293 , Infecções por HIV/imunologia , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/genética , HIV-1/isolamento & purificação , Células Hep G2 , Humanos , Imunidade Inata/imunologia , Inflamassomos/genética , Inflamassomos/imunologia , Macrófagos/metabolismo , Macrófagos/virologia , Proteínas Nucleares/genética , Fator de Transcrição Sp1/genética , Replicação Viral
10.
Nat Commun ; 11(1): 3904, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32764536

RESUMO

A major challenge in chemotherapy is chemotherapy resistance in cells lacking p53. Here we demonstrate that NIP30, an inhibitor of the oncogenic REGγ-proteasome, attenuates cancer cell growth and sensitizes p53-compromised cells to chemotherapeutic agents. NIP30 acts by binding to REGγ via an evolutionarily-conserved serine-rich domain with 4-serine phosphorylation. We find the cyclin-dependent phosphatase CDC25A is a key regulator for NIP30 phosphorylation and modulation of REGγ activity during the cell cycle or after DNA damage. We validate CDC25A-NIP30-REGγ mediated regulation of the REGγ target protein p21 in vivo using p53-/- and p53/REGγ double-deficient mice. Moreover, Phosphor-NIP30 mimetics significantly increase the growth inhibitory effect of chemotherapeutic agents in vitro and in vivo. Given that NIP30 is frequently mutated in the TCGA cancer database, our results provide insight into the regulatory pathway controlling the REGγ-proteasome in carcinogenesis and offer a novel approach to drug-resistant cancer therapy.


Assuntos
Autoantígenos/metabolismo , Proteínas Nucleares/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/metabolismo , Proteína Supressora de Tumor p53/deficiência , Animais , Autoantígenos/genética , Ciclo Celular , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Resistencia a Medicamentos Antineoplásicos , Células HEK293 , Xenoenxertos , Humanos , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Fosforilação , Complexo de Endopeptidases do Proteassoma/deficiência , Complexo de Endopeptidases do Proteassoma/genética , Proteína Supressora de Tumor p53/genética , Fosfatases cdc25/metabolismo
11.
Nat Commun ; 11(1): 3807, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32733036

RESUMO

The human genome contains an estimated 600 ubiquitin E3 ligases, many of which are single-subunit E3s (ssE3s) that can bind to both substrate and ubiquitin-loaded E2 (E2~Ub). Within ssE3s structural disorder tends to be located in substrate binding and domain linking regions. RNF4 is a ssE3 ligase with a C-terminal RING domain and disordered N-terminal region containing SUMO Interactions Motifs (SIMs) required to bind SUMO modified substrates. Here we show that, although the N-terminal region of RNF4 bears no secondary structure, it maintains a compact global architecture primed for SUMO interaction. Segregated charged regions within the RNF4 N-terminus promote compaction, juxtaposing RING domain and SIMs to facilitate substrate ubiquitination. Mutations that induce a more extended shape reduce ubiquitination activity. Our result offer insight into a key step in substrate ubiquitination by a member of the largest ubiquitin ligase subtype and reveal how a defined architecture within a disordered region contributes to E3 ligase function.


Assuntos
Proteínas Intrinsicamente Desordenadas/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Humanos , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Nucleares/genética , Ligação Proteica , Domínios Proteicos , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
12.
Nat Commun ; 11(1): 4063, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792525

RESUMO

The neuroendocrine hypothalamus is the central regulator of vital physiological homeostasis and behavior. However, the cellular and molecular properties of hypothalamic neural progenitors remain unexplored. Here, hypothalamic radial glial (hRG) and hypothalamic mantle zone radial glial (hmRG) cells are found to be neural progenitors in the developing mammalian hypothalamus. The hmRG cells originate from hRG cells and produce neurons. During the early development of hypothalamus, neurogenesis occurs in radial columns and is initiated from hRG cells. The radial glial fibers are oriented toward the locations of hypothalamic subregions which act as a scaffold for neuronal migration. Furthermore, we use single-cell RNA sequencing to reveal progenitor subtypes in human developing hypothalamus and characterize specific progenitor genes, such as TTYH1, HMGA2, and FAM107A. We also demonstrate that HMGA2 is involved in E2F1 pathway, regulating the proliferation of progenitor cells by targeting on the downstream MYBL2. Different neuronal subtypes start to differentiate and express specific genes of hypothalamic nucleus at gestational week 10. Finally, we reveal the developmental conservation of nuclear structures and marker genes in mouse and human hypothalamus. Our identification of cellular and molecular properties of neural progenitors provides a basic understanding of neurogenesis and regional formation of the non-laminated hypothalamus.


Assuntos
Hipotálamo/citologia , Hipotálamo/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Animais , Análise por Conglomerados , Feminino , Genes Supressores de Tumor , Proteína HMGA2/genética , Proteína HMGA2/metabolismo , Humanos , Hibridização In Situ , Mamíferos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Neurogênese/genética , Neurogênese/fisiologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Gravidez
13.
Nat Commun ; 11(1): 4338, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859893

RESUMO

Reversible phosphorylation of Pol II and accessory factors helps order the transcription cycle. Here, we define two kinase-phosphatase switches that operate at different points in human transcription. Cdk9/cyclin T1 (P-TEFb) catalyzes inhibitory phosphorylation of PP1 and PP4 complexes that localize to 3' and 5' ends of genes, respectively, and have overlapping but distinct specificities for Cdk9-dependent phosphorylations of Spt5, a factor instrumental in promoter-proximal pausing and elongation-rate control. PP1 dephosphorylates an Spt5 carboxy-terminal repeat (CTR), but not Spt5-Ser666, a site between Kyrpides-Ouzounis-Woese (KOW) motifs 4 and 5, whereas PP4 can target both sites. In vivo, Spt5-CTR phosphorylation decreases as transcription complexes pass the cleavage and polyadenylation signal (CPS) and increases upon PP1 depletion, consistent with a PP1 function in termination first uncovered in yeast. Depletion of PP4-complex subunits increases phosphorylation of both Ser666 and the CTR, and promotes redistribution of promoter-proximally paused Pol II into gene bodies. These results suggest that switches comprising Cdk9 and either PP4 or PP1 govern pause release and the elongation-termination transition, respectively.


Assuntos
Quinase 9 Dependente de Ciclina/metabolismo , RNA Polimerase II/metabolismo , Transcrição Genética/fisiologia , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Células HCT116 , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosforilação , Fator B de Elongação Transcricional Positiva/metabolismo , Interferência de RNA , RNA Polimerase II/genética , Receptores de Neuropeptídeo Y/metabolismo , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismo
14.
Cardiovasc Ther ; 2020: 9397109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821285

RESUMO

Chronic systemic inflammation contributes to cardiovascular disease (CVD) and correlates with the abundance of acute phase response (APR) proteins in the liver and plasma. Bromodomain and extraterminal (BET) proteins are epigenetic readers that regulate inflammatory gene transcription. We show that BET inhibition by the small molecule apabetalone reduces APR gene and protein expression in human hepatocytes, mouse models, and plasma from CVD patients. Steady-state expression of serum amyloid P, plasminogen activator inhibitor 1, and ceruloplasmin, APR proteins linked to CVD risk, is reduced by apabetalone in cultured hepatocytes and in humanized mouse liver. In cytokine-stimulated hepatocytes, apabetalone reduces the expression of C-reactive protein (CRP), alpha-2-macroglobulin, and serum amyloid P. The latter two are also reduced by apabetalone in the liver of endotoxemic mice. BET knockdown in vitro also counters cytokine-mediated induction of the CRP gene. Mechanistically, apabetalone reduces the cytokine-driven increase in BRD4 BET occupancy at the CRP promoter, confirming that transcription of CRP is BET-dependent. In patients with stable coronary disease, plasma APR proteins CRP, IL-1 receptor antagonist, and fibrinogen γ decrease after apabetalone treatment versus placebo, resulting in a predicted downregulation of the APR pathway and cytokine targets. We conclude that CRP and components of the APR pathway are regulated by BET proteins and that apabetalone counters chronic cytokine signaling in patients.


Assuntos
Anti-Inflamatórios/farmacologia , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Citocinas/metabolismo , Endotoxemia/tratamento farmacológico , Epigênese Genética/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Quinazolinonas/farmacologia , Fatores de Transcrição/metabolismo , Animais , Sítios de Ligação , Proteína C-Reativa/genética , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Células Cultivadas , Ceruloplasmina/genética , Ceruloplasmina/metabolismo , Citocinas/genética , Modelos Animais de Doenças , Endotoxemia/genética , Endotoxemia/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas Nucleares/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Regiões Promotoras Genéticas , Componente Amiloide P Sérico/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , alfa-Macroglobulinas/genética , alfa-Macroglobulinas/metabolismo
15.
PLoS Genet ; 16(8): e1008569, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32810145

RESUMO

Correct bioriented attachment of sister chromatids to the mitotic spindle is essential for chromosome segregation. In budding yeast, the conserved protein shugoshin (Sgo1) contributes to biorientation by recruiting the protein phosphatase PP2A-Rts1 and the condensin complex to centromeres. Using peptide prints, we identified a Serine-Rich Motif (SRM) of Sgo1 that mediates the interaction with condensin and is essential for centromeric condensin recruitment and the establishment of biorientation. We show that the interaction is regulated via phosphorylation within the SRM and we determined the phospho-sites using mass spectrometry. Analysis of the phosphomimic and phosphoresistant mutants revealed that SRM phosphorylation disrupts the shugoshin-condensin interaction. We present evidence that Mps1, a central kinase in the spindle assembly checkpoint, directly phosphorylates Sgo1 within the SRM to regulate the interaction with condensin and thereby condensin localization to centromeres. Our findings identify novel mechanisms that control shugoshin activity at the centromere in budding yeast.


Assuntos
Adenosina Trifosfatases/metabolismo , Centrômero/metabolismo , Proteínas de Ligação a DNA/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Motivos de Aminoácidos , Proteínas Nucleares/química , Proteínas Nucleares/genética , Fosforilação , Ligação Proteica , Proteína Fosfatase 2/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
16.
PLoS Genet ; 16(8): e1008990, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32810142

RESUMO

The kinetochore, a multi-protein complex assembled on centromeres, is essential to segregate chromosomes during cell division. Deficiencies in kinetochore function can lead to chromosomal instability and aneuploidy-a hallmark of cancer cells. Kinetochore function is controlled by recruitment of regulatory proteins, many of which have been documented, however their function often remains uncharacterized and many are yet to be identified. To identify candidates of kinetochore regulation we used a proteome-wide protein association strategy in budding yeast and detected many proteins that are involved in post-translational modifications such as kinases, phosphatases and histone modifiers. We focused on the Polo-like kinase, Cdc5, and interrogated which cellular components were sensitive to constitutive Cdc5 localization. The kinetochore is particularly sensitive to constitutive Cdc5 kinase activity. Targeting Cdc5 to different kinetochore subcomplexes produced diverse phenotypes, consistent with multiple distinct functions at the kinetochore. We show that targeting Cdc5 to the inner kinetochore, the constitutive centromere-associated network (CCAN), increases the levels of centromeric RNA via an SPT4 dependent mechanism.


Assuntos
Proteínas de Ciclo Celular/genética , Centrômero/genética , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Elongação da Transcrição/genética , Anáfase/genética , Proteínas Cromossômicas não Histona/genética , Segregação de Cromossomos/genética , Histonas/genética , Humanos , Cinetocoros/metabolismo , Mitose/genética , Fenótipo , Fosforilação/genética , RNA/genética , Saccharomyces cerevisiae/genética
17.
Science ; 370(6513): 241-247, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32855215

RESUMO

Recent outbreaks of Ebola virus (EBOV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have exposed our limited therapeutic options for such diseases and our poor understanding of the cellular mechanisms that block viral infections. Using a transposon-mediated gene-activation screen in human cells, we identify that the major histocompatibility complex (MHC) class II transactivator (CIITA) has antiviral activity against EBOV. CIITA induces resistance by activating expression of the p41 isoform of invariant chain CD74, which inhibits viral entry by blocking cathepsin-mediated processing of the Ebola glycoprotein. We further show that CD74 p41 can block the endosomal entry pathway of coronaviruses, including SARS-CoV-2. These data therefore implicate CIITA and CD74 in host defense against a range of viruses, and they identify an additional function of these proteins beyond their canonical roles in antigen presentation.


Assuntos
Antígenos de Diferenciação de Linfócitos B/fisiologia , Betacoronavirus/fisiologia , Infecções por Coronavirus/imunologia , Ebolavirus/fisiologia , Doença pelo Vírus Ebola/imunologia , Antígenos de Histocompatibilidade Classe II/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Proteínas Nucleares/fisiologia , Pneumonia Viral/imunologia , Transativadores/fisiologia , Internalização do Vírus , Antígenos de Diferenciação de Linfócitos B/genética , Linhagem Celular Tumoral , Infecções por Coronavirus/virologia , Elementos de DNA Transponíveis , Endossomos/virologia , Testes Genéticos , Doença pelo Vírus Ebola/virologia , Antígenos de Histocompatibilidade Classe II/genética , Interações Hospedeiro-Patógeno/genética , Humanos , Proteínas Nucleares/genética , Pandemias , Pneumonia Viral/virologia , Transativadores/genética , Transcrição Genética
18.
PLoS One ; 15(8): e0236808, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32750061

RESUMO

BACKGROUND: Ataxia with oculomotor apraxia type 1 (AOA1) is a rare autosomal recessive cerebellar ataxia, caused by mutations in the APTX gene. The disease is characterized by early-onset cerebellar ataxia, oculomotor apraxia and severe axonal polyneuropathy. The aim of this study was to detect the disease-causing variants in two unrelated consanguineous Jordanian families with cerebellar ataxia using whole exome sequencing (WES), and to correlate the identified mutation(s) with the clinical and cellular phenotypes. METHODS: WES was performed in three affected individuals and segregation analysis of p.W279* APTX candidate variant was performed. Expression levels of APTX were measured in patients' skin fibroblasts and peripheral blood mononuclear cells, followed by western blot analysis in skin fibroblasts. Genotoxicity assay was performed to detect the sensitivity of APTX mutated cells to H2O2, MMC, MMS and etoposide. RESULTS: A recurrent homozygous nonsense variant in APTX gene (c.837G>A, p.W279*) was revealed in all affected individuals. qRT-PCR showed normal APTX levels in peripheral blood and lower levels in fibroblast cells. However, western blot showed the absence of APTX protein in patients' skin fibroblasts. Significant hypersensitivity to H2O2, MMC and etoposide and lack of sensitivity to MMS were noted. CONCLUSIONS: This is the first study to report the identification of a nonsense variant in the APTX gene (c.837G>A; p.W279*) in AOA1 patients within the Jordanian population. This study confirmed the need of WES to assist in the diagnosis of cerebellar ataxia and it emphasizes the importance of studying the pathophysiology of the APTX gene.


Assuntos
Ataxia Cerebelar/genética , Códon sem Sentido , Dano ao DNA , Proteínas de Ligação a DNA/genética , Proteínas Nucleares/genética , Criança , Pré-Escolar , Consanguinidade , DNA/efeitos dos fármacos , Feminino , Humanos , Masculino , Mutagênicos/farmacologia , Sequenciamento Completo do Exoma
19.
PLoS Genet ; 16(7): e1008933, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32692737

RESUMO

Structure-specific endonucleases (SSEs) play key roles in DNA replication, recombination, and repair. SSEs must be tightly regulated to ensure genome stability but their regulatory mechanisms remain incompletely understood. Here, we show that in the fission yeast Schizosaccharomyces pombe, the activities of two SSEs, Dna2 and Rad16 (ortholog of human XPF), are temporally controlled during the cell cycle by the CRL4Cdt2 ubiquitin ligase. CRL4Cdt2 targets Pxd1, an inhibitor of Dna2 and an activator of Rad16, for degradation in S phase. The ubiquitination and degradation of Pxd1 is dependent on CRL4Cdt2, PCNA, and a PCNA-binding degron motif on Pxd1. CRL4Cdt2-mediated Pxd1 degradation prevents Pxd1 from interfering with the normal S-phase functions of Dna2. Moreover, Pxd1 degradation leads to a reduction of Rad16 nuclease activity in S phase, and restrains Rad16-mediated single-strand annealing, a hazardous pathway of repairing double-strand breaks. These results demonstrate a new role of the CRL4Cdt2 ubiquitin ligase in genome stability maintenance and shed new light on how SSE activities are regulated during the cell cycle.


Assuntos
Proteínas de Ligação a DNA/genética , Endonucleases Flap/genética , Proteínas Nucleares/genética , Proteínas de Schizosaccharomyces pombe/genética , Reparo do DNA/genética , Replicação do DNA/genética , Instabilidade Genômica/genética , Humanos , Fase S/genética , Schizosaccharomyces/genética , Ubiquitina/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/genética
20.
PLoS Genet ; 16(7): e1008904, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32730253

RESUMO

The conserved ATPase, PCH-2/TRIP13, is required during both the spindle checkpoint and meiotic prophase. However, its specific role in regulating meiotic homolog pairing, synapsis and recombination has been enigmatic. Here, we report that this enzyme is required to proofread meiotic homolog interactions. We generated a mutant version of PCH-2 in C. elegans that binds ATP but cannot hydrolyze it: pch-2E253Q. In vitro, this mutant can bind a known substrate but is unable to remodel it. This mutation results in some non-homologous synapsis and impaired crossover assurance. Surprisingly, worms with a null mutation in PCH-2's adapter protein, CMT-1, the ortholog of p31comet, localize PCH-2 to meiotic chromosomes, exhibit non-homologous synapsis and lose crossover assurance. The similarity in phenotypes between cmt-1 and pch-2E253Q mutants suggest that PCH-2 can bind its meiotic substrates in the absence of CMT-1, in contrast to its role during the spindle checkpoint, but requires its adapter to hydrolyze ATP and remodel them.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ciclo Celular/genética , Meiose/genética , Proteínas Nucleares/genética , Adenosina Trifosfatases/genética , Trifosfato de Adenosina/genética , Animais , Caenorhabditis elegans/genética , Pareamento Cromossômico/genética , Segregação de Cromossomos/genética , Cromossomos/genética , Humanos , Mutação/genética , Fuso Acromático/genética
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