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1.
J Renin Angiotensin Aldosterone Syst ; 21(4): 1470320320963939, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33045911

RESUMO

OBJECTIVE: The previous studies on angiotensin converting enzyme (ACE) insertion/deletion (I/D) genetic polymorphism and glioma risk were inconsistent. Therefore, we performed a meta-analysis to assess the association between ACE I/D polymorphisms and glioma risk. METHODS AND RESULTS: In total, four populations (1110 cases and 1335 controls) on ACE I/D polymorphism were included. Overall, the meta-analysis demonstrated no significant association between ACE I/D polymorphism and glioma risk. In addition, the analysis of the association of ACE I/D polymorphism and clinical grade also showed no significant association. CONCLUSION: Our meta-analysis didn't find a significant association between ACE I/D polymorphism glioma risk. However, further studies with larger sample size and more ethnic groups are required to confirm the results.


Assuntos
Neoplasias Encefálicas/genética , Deleção de Genes , Predisposição Genética para Doença/genética , Glioma/genética , Mutagênese Insercional/genética , Peptidil Dipeptidase A/genética , Polimorfismo Genético/genética , Neoplasias Encefálicas/epidemiologia , Glioma/epidemiologia , Humanos , Medição de Risco
2.
Folia Biol (Praha) ; 66(3): 91-103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33069188

RESUMO

The most recent genome-editing system called CRISPR-Cas9 (clustered regularly interspaced short palindromic repeat system with associated protein 9-nuclease) was employed to delete four non-essential genes (i.e., Caeco1, Caidh1, Carom2, and Cataf10) individually to establish their gene functionality annotations in pathogen Candida albicans. The biological roles of these genes were investigated with respect to the cell wall integrity and biogenesis, calcium/calcineurin pathways, susceptibility of mutants towards temperature, drugs and salts. All the mutants showed increased vulnerability compared to the wild-type background strain towards the cell wall-perturbing agents, (antifungal) drugs and salts. All the mutants also exhibited repressed and defective hyphal growth and smaller colony size than control CA14. The cell cycle of all the mutants decreased enormously except for those with Carom2 deletion. The budding index and budding size also increased for all mutants with altered bud shape. The disposition of the mutants towards cell wall-perturbing enzymes disclosed lower survival and more rapid cell wall lysis events than in wild types. The pathogenicity and virulence of the mutants was checked by adhesion assay, and strains lacking rom2 and eco1 were found to possess the least adhesion capacity, which is synonymous to their decreased pathogenicity and virulence.


Assuntos
Candida albicans/fisiologia , Proteínas Fúngicas/fisiologia , Genes Fúngicos , Acetiltransferases/deficiência , Acetiltransferases/genética , Acetiltransferases/fisiologia , Antifúngicos/farmacologia , Sistemas CRISPR-Cas , Cálcio/fisiologia , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Candida albicans/patogenicidade , Cátions/farmacologia , Adesão Celular , Ciclo Celular , Parede Celular/efeitos dos fármacos , Quitinases/farmacologia , Dano ao DNA , Proteínas Fúngicas/genética , Deleção de Genes , Glucana Endo-1,3-beta-D-Glucosidase/farmacologia , Hifas/crescimento & desenvolvimento , Isocitrato Desidrogenase/deficiência , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/fisiologia , Fases de Leitura Aberta , Reprodução Assexuada , Fatores Associados à Proteína de Ligação a TATA/deficiência , Fatores Associados à Proteína de Ligação a TATA/genética , Fatores Associados à Proteína de Ligação a TATA/fisiologia , Virulência/genética
3.
Nat Commun ; 11(1): 5060, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033246

RESUMO

Fusion oncogenes (FOs) are common in many cancer types and are powerful drivers of tumor development. Because their expression is exclusive to cancer cells and their elimination induces cell apoptosis in FO-driven cancers, FOs are attractive therapeutic targets. However, specifically targeting the resulting chimeric products is challenging. Based on CRISPR/Cas9 technology, here we devise a simple, efficient and non-patient-specific gene-editing strategy through targeting of two introns of the genes involved in the rearrangement, allowing for robust disruption of the FO specifically in cancer cells. As a proof-of-concept of its potential, we demonstrate the efficacy of intron-based targeting of transcription factors or tyrosine kinase FOs in reducing tumor burden/mortality in in vivo models. The FO targeting approach presented here might open new horizons for the selective elimination of cancer cells.


Assuntos
Sistemas CRISPR-Cas/genética , Neoplasias/genética , Fusão Oncogênica/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Doxorrubicina/uso terapêutico , Proteínas de Fusão bcr-abl/genética , Deleção de Genes , Loci Gênicos , Instabilidade Genômica , Células HEK293 , Humanos , Íntrons/genética , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Proteínas de Fusão Oncogênica/genética , RNA Guia/metabolismo , Reprodutibilidade dos Testes , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Pediatrics ; 146(4)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32938777

RESUMO

BACKGROUND AND OBJECTIVES: Genetic testing is recommended for individuals with autism spectrum disorder (ASD). Pathogenic yield varies by clinician and/or patient characteristics. Our objectives were to determine the pathogenic yield of genetic testing, the variability in rate of pathogenic results based on subject characteristics, and the percentage of pathogenic findings resulting in further medical recommendations in toddlers with a Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition diagnosis of ASD. METHODS: We conducted a retrospective chart review of 500 toddlers, 18 to 36 months, diagnosed with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition ASD (mean age: 25.8 months, 79% male). Subject demographics, medical and neuropsychological characteristics, and genetic test results were abstracted. Genetic results were divided into negative or normal, variants of unknown significance, and pathogenic. Subject characteristics were compared across results. Manual chart review determined if further recommendations were made after pathogenic results. RESULTS: Over half of subjects (59.8%, n = 299) completed genetic testing, and of those, 36 (12.0%) had pathogenic findings. There were no significant differences in Bayley Scales of Infant Development cognitive (P = .112), language (P = .898), or motor scores (P = .488) among children with negative or normal findings versus a variant of unknown significance versus pathogenic findings. Medical recommendations in response to the genetic finding were made for 72.2% of those with pathogenic results. CONCLUSIONS: Our findings reinforce the importance of genetic testing for toddlers diagnosed with ASD given the 12% yield and lack of phenotypic differences between subjects with and without pathogenic findings. The majority of pathogenic results lead to further medical recommendations.


Assuntos
Transtorno do Espectro Autista/genética , Testes Genéticos/estatística & dados numéricos , Transtorno do Espectro Autista/diagnóstico , Transtornos Dismórficos Corporais/diagnóstico , Transtornos Dismórficos Corporais/genética , Pré-Escolar , Cromossomos Humanos 13-15 , Cognição , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Proteína do X Frágil de Retardo Mental/genética , Deleção de Genes , Duplicação Gênica , Testes Genéticos/métodos , Humanos , Lactente , Desenvolvimento da Linguagem , Masculino , Análise em Microsséries , Mosaicismo , Destreza Motora , Mutação , Fenótipo , Encaminhamento e Consulta , Estudos Retrospectivos
5.
Mol Cell ; 80(1): 87-101.e5, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32931746

RESUMO

Studies in three mouse models of breast cancer identified profound discrepancies between cell-autonomous and systemic Akt1- or Akt2-inducible deletion on breast cancer tumorigenesis and metastasis. Although systemic Akt1 deletion inhibits metastasis, cell-autonomous Akt1 deletion does not. Single-cell mRNA sequencing revealed that systemic Akt1 deletion maintains the pro-metastatic cluster within primary tumors but ablates pro-metastatic neutrophils. Systemic Akt1 deletion inhibits metastasis by impairing survival and mobilization of tumor-associated neutrophils. Importantly, either systemic or neutrophil-specific Akt1 deletion is sufficient to inhibit metastasis of Akt-proficient tumors. Thus, Akt1-specific inhibition could be therapeutic for breast cancer metastasis regardless of primary tumor origin. Systemic Akt2 deletion does not inhibit and exacerbates mammary tumorigenesis and metastasis, but cell-autonomous Akt2 deletion prevents breast cancer tumorigenesis by ErbB2. Elevated circulating insulin level induced by Akt2 systemic deletion hyperactivates tumor Akt, exacerbating ErbB2-mediated tumorigenesis, curbed by pharmacological reduction of the elevated insulin.


Assuntos
Neoplasias Mamárias Animais/enzimologia , Neoplasias Mamárias Animais/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Carcinogênese/patologia , Feminino , Deleção de Genes , Humanos , Insulina/metabolismo , Isoenzimas/metabolismo , Metástase Neoplásica , Neutrófilos/metabolismo , Receptor ErbB-2/metabolismo
6.
Tokai J Exp Clin Med ; 45(3): 113-116, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32901897

RESUMO

Mutations in the gene encoding epidermal growth factor receptor (EGFR) are the most frequent driver mutations in lung adenocarcinoma in Japan. Exon 19 deletion and L858R mutation in exon 21 are the most common EGFR mutations. Uncommon mutations, such as G719X, S768I, and L861Q, and compound mutations, combinations of 2 common or uncommon mutations, have also been reported. EGFR tyrosine kinase inhibitors (TKIs) are effective against cancers harboring common mutations; however, their efficacy against cancers with uncommon or compound mutations remains unclear. We report the case of a 67-year-old man with lung adenocarcinoma (clinical stage IIIA [cT1N2M0]), harboring an uncommon compound mutation, G719X and S768I. The cancer progressed within 2 months of initial chemoradiotherapy. Treatment with afatinib (40 mg/day) produced a partial response, which was maintained for 17 months with continued treatment. A literature review revealed that lung cancer with G719X/S768I compound mutation exhibited good response to EGFR-TKIs, even better than that of lung cancers with single uncommon mutations.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Afatinib/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Idoso , Receptores ErbB/genética , Éxons/genética , Deleção de Genes , Humanos , Masculino , Resultado do Tratamento
7.
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
8.
PLoS Pathog ; 16(9): e1008850, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32956404

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne orthonairovirus that has become a serious threat to the public health. CCHFV has a single-stranded, tripartite RNA genome composed of L, M, and S segments. Cleavage of the M polyprotein precursor generates the two envelope glycoproteins (GPs) as well as three secreted nonstructural proteins GP38 and GP85 or GP160, representing GP38 only or GP38 linked to a mucin-like protein (MLD), and a double-membrane-spanning protein called NSm. Here, we examined the relevance of each M-segment non-structural proteins in virus assembly, egress and infectivity using a well-established CCHFV virus-like-particle system (tc-VLP). Deletion of MLD protein had no impact on infectivity although it reduced by 60% incorporation of GPs into particles. Additional deletion of GP38 abolished production of infectious tc-VLPs. The loss of infectivity was associated with impaired Gc maturation and exclusion from the Golgi, showing that Gn is not sufficient to target CCHFV GPs to the site of assembly. Consistent with this, efficient complementation was achieved in cells expressing MLD-GP38 in trans with increased levels of preGc to Gc conversion, co-targeting to the Golgi, resulting in particle incorporation and restored infectivity. Contrastingly, a MLD-GP38 variant retained in the ER allowed preGc cleavage but failed to rescue miss-localization or infectivity. NSm deletion, conversely, did not affect trafficking of Gc but interfered with Gc processing, particle formation and secretion. NSm expression affected N-glycosylation of different viral proteins most likely due to increased speed of trafficking through the secretory pathway. This highlights a potential role of NSm in overcoming Golgi retention and facilitating CCHFV egress. Thus, deletions of GP38 or NSm demonstrate their important role on CCHFV particle production and infectivity. GP85 is an essential viral factor for preGc cleavage, trafficking and Gc incorporation into particles, whereas NSm protein is involved in CCHFV assembly and virion secretion.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo/fisiologia , Proteínas Estruturais Virais , Montagem de Vírus , Linhagem Celular Tumoral , Deleção de Genes , Humanos , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/metabolismo
9.
PLoS Pathog ; 16(9): e1008852, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32960931

RESUMO

Enzymatic inactivation of Rho-family GTPases by the glucosyltransferase domain of Clostridioides difficile Toxin B (TcdB) gives rise to various pathogenic effects in cells that are classically thought to be responsible for the disease symptoms associated with C. difficile infection (CDI). Recent in vitro studies have shown that TcdB can, under certain circumstances, induce cellular toxicities that are independent of glucosyltransferase (GT) activity, calling into question the precise role of GT activity. Here, to establish the importance of GT activity in CDI disease pathogenesis, we generated the first described mutant strain of C. difficile producing glucosyltransferase-defective (GT-defective) toxin. Using allelic exchange (AE) technology, we first deleted tcdA in C. difficile 630Δerm and subsequently introduced a deactivating D270N substitution in the GT domain of TcdB. To examine the role of GT activity in vivo, we tested each strain in two different animal models of CDI pathogenesis. In the non-lethal murine model of infection, the GT-defective mutant induced minimal pathology in host tissues as compared to the profound caecal inflammation seen in the wild-type and 630ΔermΔtcdA (ΔtcdA) strains. In the more sensitive hamster model of CDI, whereas hamsters in the wild-type or ΔtcdA groups succumbed to fulminant infection within 4 days, all hamsters infected with the GT-defective mutant survived the 10-day infection period without primary symptoms of CDI or evidence of caecal inflammation. These data demonstrate that GT activity is indispensable for disease pathogenesis and reaffirm its central role in disease and its importance as a therapeutic target for small-molecule inhibition.


Assuntos
Proteínas de Bactérias , Toxinas Bacterianas , Clostridium difficile , Enterocolite Pseudomembranosa , Glucosiltransferases , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Clostridium difficile/enzimologia , Clostridium difficile/genética , Clostridium difficile/patogenicidade , Cricetinae , Modelos Animais de Doenças , Enterocolite Pseudomembranosa/enzimologia , Enterocolite Pseudomembranosa/genética , Enterocolite Pseudomembranosa/patologia , Feminino , Deleção de Genes , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Masculino , Camundongos
10.
Nat Commun ; 11(1): 4778, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963241

RESUMO

Obtaining genetic variation information from indica rice hybrid parents and identification of loci associated with heterosis are important for hybrid rice breeding. Here, we resequence 1,143 indica accessions mostly selected from the parents of superior hybrid rice cultivars of China, identify genetic variations, and perform kinship analysis. We find different hybrid rice crossing patterns between 3- and 2-line superior hybrid lines. By calculating frequencies of parental variation differences (FPVDs), a more direct approach for studying rice heterosis, we identify loci that are linked to heterosis, which include 98 in superior 3-line hybrids and 36 in superior 2-line hybrids. As a proof of concept, we find two accessions harboring a deletion in OsNramp5, a previously reported gene functioning in cadmium absorption, which can be used to mitigate rice grain cadmium levels through hybrid breeding. Resource of indica rice genetic variation reported in this study will be valuable to geneticists and breeders.


Assuntos
Variação Genética , Vigor Híbrido/genética , Oryza/genética , Cruzamento , Proteínas de Transporte de Cátions/genética , China , Cruzamentos Genéticos , Deleção de Genes , Genes de Plantas , Hibridização Genética , Oryza/classificação , Filogenia , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único
11.
PLoS One ; 15(9): e0235183, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32956421

RESUMO

Members of the broad complex, tram track, bric-a-brac and zinc finger (BTB-ZF) family of transcription factors, such as BCL-6, ZBTB20, and ZBTB32, regulate antigen-specific B cell differentiation, plasma cell longevity, and the duration of antibody production. We found that ZBTB38, a different member of the BTB-ZF family that binds methylated DNA at CpG motifs, is highly expressed by germinal center B cells and plasma cells. To define the functional role of ZBTB38 in B cell responses, we generated mice conditionally deficient in this transcription factor. Germinal center B cells lacking ZBTB38 dysregulated very few genes relative to wild-type and heterozygous littermate controls. Accordingly, mice with hematopoietic-specific deletion of Zbtb38 showed normal germinal center B cell numbers and antibody responses following immunization with hapten-protein conjugates. Memory B cells from these animals functioned normally in secondary recall responses. Despite expression of ZBTB38 in hematopoietic stem cells, progenitors and mature myeloid and lymphoid lineages were also present in normal numbers in mutant mice. These data demonstrate that ZBTB38 is dispensable for hematopoiesis and antibody responses. These conditional knockout mice may instead be useful in defining the functional importance of ZBTB38 in other cell types and contexts.


Assuntos
Formação de Anticorpos , Linfócitos B/imunologia , Proteínas Repressoras/imunologia , Animais , Linfócitos B/citologia , Deleção de Genes , Expressão Gênica , Hematopoese , Imunização , Camundongos , Camundongos Knockout , Proteínas Repressoras/genética
12.
Clin Dermatol ; 38(4): 421-431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32972601

RESUMO

Café au lait spots are common birthmarks seen sporadically and in association with several genetic syndromes. Dermatologists are often asked to evaluate these birthmarks both by other physicians and by parents. In some cases, it is challenging to know when and how to pursue further evaluation. Diagnostic challenges may come in the form of the appearance of the individual lesions, areas and patterns of cutaneous involvement, and associated features (or lack thereof). In this review, we aim to clarify when and how to evaluate the child with multiple or patterned café au lait spots and to explain some emerging concepts in our understanding of the genetics of these lesions.


Assuntos
Manchas Café com Leite/congênito , Manchas Café com Leite/diagnóstico , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/genética , Dermatopatias Genéticas/diagnóstico , Dermatopatias Genéticas/genética , Pele/patologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Manchas Café com Leite/genética , Manchas Café com Leite/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Deleção de Genes , Estudos de Associação Genética , Mutação em Linhagem Germinativa , Humanos , Lactente , Recém-Nascido , Masculino , Neurofibromatose 1/patologia , Neurofibromina 1/genética , Dermatopatias Genéticas/patologia , Síndrome
13.
Ann Hematol ; 99(10): 2343-2349, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32833105

RESUMO

Ibrutinib-based therapy represents a recent success in managing high-risk CLL patients with 17p/TP53 deletion. However, a subset of CLL patients are resistant to therapy. Deletion of lipoprotein lipase (LPL) has been postulated as a potential evasion mechanism to ibrutinib-based therapy. In this study, we assessed for LPL deletion by fluorescence in situ hybridization in 176 consecutive CLL patients with 17p/TP53 deletion. LPL deletion was detected in 35 (20%) of CLL patients. Patients with LPL deletion (del) showed a higher frequency of CD38 expression but have comparable frequencies of somatic hypermutation and ZAP-70 expression compared with patients with normal (nml) LPL. Gene mutation analysis showed that TP53 was mutated in 68% of LPL-del versus 91% of LPL-nml patients. The overall response to ibrutinib-based therapy was 57%, including 37% complete remission (CR) and 20% partial remission (PR) in patients with LPL-del versus 90% (56% CR and 34% PR) in patients with LPL-nml (p < 0.001). LPL-del patients also showed a poorer overall survival (OS) compared with patients with LPL-nml (median OS, 236 months versus undefined, p < 0.001). In summary, the data presented establish an association between LPL deletion, resistance to ibrutinib-based therapy, and poorer overall survival in TP53-deleted CLL patients. We suggest that LPL deletion might be utilized as a biomarker for risk stratification and to predict therapeutic response in this high-risk group of CLL patients.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Deleção de Genes , Leucemia Linfocítica Crônica de Células B/genética , Lipase Lipoproteica/deficiência , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Feminino , Genes p53 , Humanos , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Lipase Lipoproteica/genética , Lipase Lipoproteica/fisiologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Modelos de Riscos Proporcionais , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem , Medição de Risco , Rituximab/administração & dosagem , Sulfonamidas/administração & dosagem , Resultado do Tratamento , Proteína Supressora de Tumor p53/deficiência , Proteína-Tirosina Quinase ZAP-70/biossíntese , Proteína-Tirosina Quinase ZAP-70/genética
14.
Life Sci ; 258: 118204, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32763296

RESUMO

AIMS: Liver kinase B1 (LKB1) is a serine/threonine kinase. Although many biological functions of LKB1 have been identified, the role of hypothalamic LKB1 in the regulation of central energy metabolism and susceptibility to obesity is unknown. Therefore, we constructed POMC neuron-specific LKB1 knockout mice (PomcLkb1 KO) and studied it at the physiological, morphological, and molecular biology levels. MAIN METHODS: Eight-week-old male PomcLkb1 KO mice and their littermates were fed a standard chow fat diet (CFD) or a high-fat diet (HFD) for 3 months. Body weight and food intake were monitored. Dual-energy X-ray absorptiometry was used to measure the fat mass and lean mass. Glucose and insulin tolerance tests and serum biochemical markers were evaluated in the experimental mice. In addition, the levels of peripheral lipogenesis genes and central energy metabolism were measured. KEY FINDINGS: PomcLkb1 KO mice did not exhibit impairments under normal physiological conditions. After HFD intervention, the metabolic phenotype of the PomcLkb1 KO mice changed, manifesting as increased food intake and an enhanced obesity phenotype. More seriously, PomcLkb1 KO mice showed increased leptin resistance, worsened hypothalamic inflammation and reduced POMC neuronal expression. SIGNIFICANCE: We provide evidence that LKB1 in POMC neurons plays a significant role in regulating energy homeostasis. LKB1 in POMC neurons emerges as a target for therapeutic intervention against HFD-induced obesity and metabolic diseases.


Assuntos
Deleção de Genes , Neurônios/enzimologia , Obesidade/enzimologia , Pró-Opiomelanocortina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Tecido Adiposo/patologia , Animais , Dieta Hiperlipídica , Epididimo/patologia , Comportamento Alimentar , Regulação da Expressão Gênica , Glucose/metabolismo , Hipotálamo/patologia , Inflamação/patologia , Leptina/metabolismo , Fígado/enzimologia , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Obesidade/sangue , Obesidade/patologia , Pró-Opiomelanocortina/genética , Ganho de Peso
15.
Nat Commun ; 11(1): 3907, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32764578

RESUMO

Nucleic acids can fold into G-quadruplex (G4) structures that can fine-tune biological processes. Proteins are required to recognize G4 structures and coordinate their function. Here we identify Zuo1 as a novel G4-binding protein in vitro and in vivo. In vivo in the absence of Zuo1 fewer G4 structures form, cell growth slows and cells become UV sensitive. Subsequent experiments reveal that these cellular changes are due to reduced levels of G4 structures. Zuo1 function at G4 structures results in the recruitment of nucleotide excision repair (NER) factors, which has a positive effect on genome stability. Cells lacking functional NER, as well as Zuo1, accumulate G4 structures, which become accessible to translesion synthesis. Our results suggest a model in which Zuo1 supports NER function and regulates the choice of the DNA repair pathway nearby G4 structures.


Assuntos
Reparo do DNA/fisiologia , Quadruplex G , Chaperonas Moleculares/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Sítios de Ligação/genética , Dano ao DNA , Reparo do DNA/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Fúngico/metabolismo , Deleção de Genes , Aptidão Genética , Genoma Fúngico , Instabilidade Genômica , Modelos Biológicos , Chaperonas Moleculares/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
16.
Emerg Microbes Infect ; 9(1): 1900-1911, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32752979

RESUMO

The SARS-CoV-2 spike (S) protein, the viral mediator for binding and entry into the host cell, has sparked great interest as a target for vaccine development and treatments with neutralizing antibodies. Initial data suggest that the virus has low mutation rates, but its large genome could facilitate recombination, insertions, and deletions, as has been described in other coronaviruses. Here, we deep-sequenced the complete SARS-CoV-2 S gene from 18 patients (10 with mild and 8 with severe COVID-19), and found that the virus accumulates deletions upstream and very close to the S1/S2 cleavage site (PRRAR/S), generating a frameshift with appearance of a stop codon. These deletions were found in a small percentage of the viral quasispecies (2.2%) in samples from all the mild and only half the severe COVID-19 patients. Our results suggest that the virus may generate free S1 protein released to the circulation. We suggest that natural selection has favoured a "Don't burn down the house" strategy, in which free S1 protein may compete with viral particles for the ACE2 receptor, thus reducing the severity of the infection and tissue damage without losing transmission capability.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , Genoma Viral/genética , Pneumonia Viral/virologia , Quase-Espécies/genética , Infecções Respiratórias/virologia , Glicoproteína da Espícula de Coronavírus/genética , Adulto , Idoso , Biologia Computacional , Feminino , Deleção de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Clivagem do RNA , Análise de Sequência de RNA
17.
Lancet ; 396(10251): 603-611, 2020 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-32822564

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with a 382-nucleotide deletion (∆382) in the open reading frame 8 (ORF8) region of the genome have been detected in Singapore and other countries. We investigated the effect of this deletion on the clinical features of infection. METHODS: We retrospectively identified patients who had been screened for the ∆382 variant and recruited to the PROTECT study-a prospective observational cohort study conducted at seven public hospitals in Singapore. We collected clinical, laboratory, and radiological data from patients' electronic medical records and serial blood and respiratory samples taken during hospitalisation and after discharge. Individuals infected with the ∆382 variant were compared with those infected with wild-type SARS-CoV-2. Exact logistic regression was used to examine the association between the infection groups and the development of hypoxia requiring supplemental oxygen (an indicator of severe COVID-19, the primary endpoint). Follow-up for the study's primary endpoint is completed. FINDINGS: Between Jan 22 and March 21, 2020, 278 patients with PCR-confirmed SARS-CoV-2 infection were screened for the ∆382 deletion and 131 were enrolled onto the study, of whom 92 (70%) were infected with the wild-type virus, ten (8%) had a mix of wild-type and ∆382-variant viruses, and 29 (22%) had only the ∆382 variant. Development of hypoxia requiring supplemental oxygen was less frequent in the ∆382 variant group (0 [0%] of 29 patients) than in the wild-type only group (26 [28%] of 92; absolute difference 28% [95% CI 14-28]). After adjusting for age and presence of comorbidities, infection with the ∆382 variant only was associated with lower odds of developing hypoxia requiring supplemental oxygen (adjusted odds ratio 0·07 [95% CI 0·00-0·48]) compared with infection with wild-type virus only. INTERPRETATION: The ∆382 variant of SARS-CoV-2 seems to be associated with a milder infection. The observed clinical effects of deletions in ORF8 could have implications for the development of treatments and vaccines. FUNDING: National Medical Research Council Singapore.


Assuntos
Infecções por Coronavirus/virologia , Deleção de Genes , Genoma Viral/genética , Pneumonia Viral/virologia , Adulto , Idoso , Betacoronavirus , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Humanos , Hipóxia/etiologia , Hipóxia/terapia , Pessoa de Meia-Idade , Fases de Leitura Aberta , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Estudos Prospectivos , Terapia Respiratória , Índice de Gravidade de Doença , Singapura/epidemiologia , Replicação Viral
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1115-1122, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798385

RESUMO

OBJECTIVE: To analyze the significance of various abnormal signal patterns appreared in CML and B-ALL patients by using BCR/ABL/ASS1 tricolor dual-fusion probe, and to explore its application value in detecting BCR/ABL fusion gene and ASS1 gene deletion. METHODS: 50 newly diagnosed CML patients and 50 newly diagnosed B-ALL patients were detected by fluorescence in situ hybridization (FISH) with BCR/ABL/ASS1 tricolor dual-fusion probe. Meanwhile, karyotype analysis was performed on all the patients using the 24 hours short-term culture and R-banding. RESULTS: Among the 50 CML patients, Ph+ was found in 49 cases, 5 normal interphase karyotype was observed in 1 case. FISH detection showed that BCR/ABL fusion gene existed in all patients (100%), while the positive signal pathway showed that 1R1G2B2F was observed in 39 cases (78%), 2R1G2B1F in 2 cases (4%) and 1R1G2B1F in 6 cases (12%), simultaneous existence of 1R1G1B1F and 1R1G2B3F in 1 case (2%), 2R1G1B1F in 1 case (2%) 1R1G3B3F in 1 case (2%). FISH detection also showed that the karyotype of 6 case at ASS1 gene deletion (1R1G1B1F) all were simple t (9; 22) translocation, and other abnormalities not were observed. Among 50 cases of B-ALL, Ph+ was found in 13 cases, the numerical aberration and structural aberration of non t (9; 22) in 16 cases, normal karyotype in 20 cases, absence of mitotic phase in 1 case. FISH detection showed that 16 cases (32%) had BCR/ABL fusion gene including 13 cases (26%) of 1R1G2B2F, 1 case (2%) of stimultaneous exitance of 1R1G2B2F and 1R1G3B3F 1 case (2%) of 2R1G1B1F, 1 case (2%) of 1R1G3B2F. FISH detection also showed that 3 cases had BCR/ABL fusion gene, including 1 case with ASS1 gene deletion (2R1G1B1F), 1 case with classical t (9; 22) translocation (1R1G2B2F) and 1 case with BCR/ABL fusion gene and increase of ASS1 gene copy (1R1G3B3F). CONCLUSION: Tricolor dual-fusion FISH probe for detecting BCR/ABL fusion gene and ASS1 gene deletion is simple, rapid, sensitive and stable. It can detect various forms of molecular fusion and avoid the false positive results due to coincidental overlap of signals generated by D-FISH probe and ES-FISH probe. In addition, this detection method not only can directly observe the presence or absence of ASS1 gene deletion, but also improve the reliability of the positive results of newly diagnosed BCR/ABL fusion gene and accuracy of monitoring results of minimal residual disease for the subsequent visit.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteínas de Fusão bcr-abl/genética , Deleção de Genes , Humanos , Hibridização in Situ Fluorescente , Reprodutibilidade dos Testes
19.
PLoS One ; 15(8): e0237999, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822427

RESUMO

Hyper-IgD syndrome (HIDS, OMIM #260920) is a rare autosomal recessive autoinflammatory disorder caused by pathogenic variants in the mevalonate kinase (MVK) gene. HIDS has an incidence of 1:50,000 to 1:5,000, and is thought to be prevalent mainly in northern Europe. Here, we report a case series of HIDS from India, which includes ten patients from six families who presented with a wide spectrum of clinical features such as recurrent fever, oral ulcers, rash, arthritis, recurrent diarrhea, hepatosplenomegaly, and high immunoglobulin levels. Using whole exome sequencing (WES) and/or Sanger capillary sequencing, we identified five distinct genetic variants in the MVK gene from nine patients belonging to six families. The variants were classified as pathogenic or likely pathogenic as per the American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG-AMP) guidelines for annotation of sequence variants. Over 70% of patients in the present study had two recurrent mutations in MVK gene i.e. a nonsynonymous variant p.V377I, popularly known as the 'Dutch mutation', along with a splicing variant c.226+2delT in a compound heterozygous form. Identity by descent analysis in two patients with the recurrent variants identified a 6.7 MB long haplotype suggesting a founder effect in the South Indian population. Our analysis suggests that a limited number of variants account for the majority of the patients with HIDS in South India. This has implications in clinical diagnosis, as well as in the development of cost-effective approaches for genetic diagnosis and screening. To our best knowledge, this is the first and most comprehensive case series of clinically and genetically characterized patients with HIDS from India.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Deficiência de Mevalonato Quinase/patologia , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Adolescente , Pré-Escolar , Feminino , Deleção de Genes , Estudos de Associação Genética , Haplótipos , Heterozigoto , Humanos , Índia , Lactente , Masculino , Deficiência de Mevalonato Quinase/genética , Linhagem , Fosfotransferases (Aceptor do Grupo Álcool)/química , Polimorfismo de Nucleotídeo Único , Estrutura Terciária de Proteína , Sequenciamento Completo do Exoma
20.
Nat Commun ; 11(1): 4254, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848143

RESUMO

Pulmonary fibrosis (PF) is a major public health problem with limited therapeutic options. There is a clear need to identify novel mediators of PF to develop effective therapeutics. Here we show that an ER protein disulfide isomerase, thioredoxin domain containing 5 (TXNDC5), is highly upregulated in the lung tissues from both patients with idiopathic pulmonary fibrosis and a mouse model of bleomycin (BLM)-induced PF. Global deletion of Txndc5 markedly reduces the extent of PF and preserves lung function in mice following BLM treatment. Mechanistic investigations demonstrate that TXNDC5 promotes fibrogenesis by enhancing TGFß1 signaling through direct binding with and stabilization of TGFBR1 in lung fibroblasts. Moreover, TGFß1 stimulation is shown to upregulate TXNDC5 via ER stress/ATF6-dependent transcriptional control in lung fibroblasts. Inducing fibroblast-specific deletion of Txndc5 mitigates the progression of BLM-induced PF and lung function deterioration. Targeting TXNDC5, therefore, could be a novel therapeutic approach against PF.


Assuntos
Fibrose Pulmonar Idiopática/etiologia , Fibrose Pulmonar Idiopática/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Tiorredoxinas/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Bleomicina/toxicidade , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Deleção de Genes , Humanos , Fibrose Pulmonar Idiopática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Isomerases de Dissulfetos de Proteínas/genética , Dobramento de Proteína , Estabilidade Proteica , Fibrose Pulmonar/patologia , Receptor do Fator de Crescimento Transformador beta Tipo I/química , Transdução de Sinais , Tiorredoxinas/antagonistas & inibidores , Tiorredoxinas/genética , Regulação para Cima
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