Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44.613
Filtrar
1.
Adv Exp Med Biol ; 1164: 63-71, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576540

RESUMO

Gankyrin (also called PSMD10, p28, or p28GANK) is a crucial oncoprotein that is upregulated in various cancers and assumed to play pivotal roles in the initiation and progression of tumors. Although the in vitro function of gankyrin is relatively well characterized, its role in vivo remains to be elucidated. We have investigated the function of gankyrin in vivo by producing mice with liver parenchymal cell-specific gankyrin ablation (Alb-Cre;gankyrinf/f) and gankyrin deletion both in liver parenchymal and in non-parenchymal cells (Mx1-Cre;gankyrinf/f). Gankyrin deficiency both in non-parenchymal cells and parenchymal cells, but not in parenchymal cells alone, reduced STAT3 activity, interleukin-6 production, and cancer stem cell marker expression, leading to attenuated tumorigenic potential in the diethylnitrosamine hepatocarcinogenesis model. Essentially similar results were obtained by analyzing mice with intestinal epithelial cell-specific gankyrin ablation (Villin-Cre;Gankyrinf/f) and gankyrin deletion both in myeloid and epithelial cells (Mx1-Cre;Gankyrinf/f) in the colitis-associated cancer model. Clinically, gankyrin expression in the tumor microenvironment was negatively correlated with progression-free survival in patients undergoing treatment with Sorafenib for hepatocellular carcinomas. These findings indicate important roles played by gankyrin in non-parenchymal cells as well as parenchymal cells in the pathogenesis of liver cancers and colorectal cancers, and suggest that by acting both on cancer cells and on the tumor microenvironment, anti-gankyrin agents would be promising as therapeutic and preventive strategies against various cancers, and that an in vitro cell culture models that incorporate the effects of non-parenchymal cells and gankyrin would be useful for the study of human cell transformation.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Complexo de Endopeptidases do Proteassoma , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/fisiopatologia , Carcinoma Hepatocelular/terapia , Neoplasias Colorretais/genética , Neoplasias Colorretais/fisiopatologia , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Deleção de Genes , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/fisiopatologia , Neoplasias Hepáticas/terapia , Camundongos , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Fator de Transcrição STAT3/metabolismo , Microambiente Tumoral
2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(10): 1015-1018, 2019 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-31598949

RESUMO

OBJECTIVE: To carry out genetic testing and prenatal diagnosis for a family affected with Duchenne muscular dystrophy (DMD). METHODS: Multiplex ligation dependent probe amplification (MLPA) was used to detect potential deletion and duplication of the Dystrophin gene. Haplotype analysis was performed using five short tandem repeat polymorphism loci (3'-STR, 5'-STR, 45-STR, 49-STR, 50-STR of the DMD gene. RESULTS: A same deletional mutation (exons 51-55) of the DMD gene was detected in two brothers but not in their mother. The patients and fetus have inherited different haplotypes of the Dystrophin gene from their mother, suggesting that the fetus was unaffected. CONCLUSION: The mother was very likely to harbor germline mosaicism for the Dystrophin gene variant. Genetic testing of peripheral blood samples cannot rule out germline mosaicism in the mother. Prenatal diagnosis should be provided for subsequent pregnancies in this family.


Assuntos
Distrofina/genética , Deleção de Genes , Mutação em Linhagem Germinativa , Mosaicismo , Distrofia Muscular de Duchenne/genética , Éxons , Feminino , Humanos , Masculino , Gravidez , Diagnóstico Pré-Natal
3.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(9): 935-937, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31515794

RESUMO

OBJECTIVE: To explore the genetic basis for a patient with autism. METHODS: High-throughput sequencing was carried out to detect copy number variations in the patient. RESULTS: DNA sequencing found that the patient has carried a 0.11 Mb deletion in distal 2p16.3 spanning from genomic position 50 820 001 to 50 922 000, which resulted removal of exon 6 and part of intron 7 of the NRXN1 gene. The same deletion was not found his parents and brother. CONCLUSION: Partial deletion of the NRXN1 gene may underlie the disease in this patient.


Assuntos
Transtorno Autístico/genética , Moléculas de Adesão Celular Neuronais/genética , Deleção de Genes , Proteínas do Tecido Nervoso/genética , Variações do Número de Cópias de DNA , Humanos , Masculino
4.
Life Sci ; 234: 116755, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31415769

RESUMO

AIMS: Vitamin D and its receptor, vitamin D receptor (VDR), have renoprotection effect against diabetic nephropathy (DN). But the exact mechanism has not been fully elucidated. Epoxyeicosatrienoic acids (EETs) are cytochrome P450 (CYP) epoxygenase-derived metabolites of arachidonic acid, protecting against diabetes and DN. Herein, we hypothesized that activation of VDR attenuated high glucose-induced cellular injury in renal tubular epithelial cells partially through up-regulating CYP2J5 expression. MAIN METHODS: Streptozotocin (STZ) was injected to induce diabetic in wild type and Vdr-/- mice. The effects of VDR knockout and an activator of VDR, paricalcitol, on the renal injury were detected. In vitro, a murine kidney proximal tubule epithelial cell line BU.MPT induced by high glucose were treated with or without paricalcitol (30 mM) for 12 h or 24 h. KEY FINDINGS: The expression of CYP2J5 was significantly decreased both in wild type and Vdr-/- diabetic mice induced by STZ. The STZ-induced kidney architecture damage and apoptosis rate in Vdr-/- mice were more severe. In vitro, high glucose treatment strongly reduced the CYP2J5 expression and the synthesis of 14,15-EET in BU.MPT cells. Supplement of 14,15-EET significantly reduced the lactate dehydrogenase (LDH) release induced by high glucose in BU.MPT cells. Furthermore, treatment with paricalcitol attenuated cellular injury and restored the expression of CYP2J5 reduced by high glucose in BU.MPT cells. SIGNIFICANCE: We conclude that activation of VDR attenuates high glucose-induced cellular injury partially dependent on CYP2J5 in murine renal tubule epithelial cells and paricalcitol may represent a potential therapy for DN.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/etiologia , Ergocalciferóis/farmacologia , Túbulos Renais Proximais/efeitos dos fármacos , Receptores de Calcitriol/agonistas , Animais , Linhagem Celular , Sistema Enzimático do Citocromo P-450/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/patologia , Ergocalciferóis/uso terapêutico , Deleção de Genes , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Masculino , Camundongos , Camundongos Knockout , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo
5.
Life Sci ; 234: 116793, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465735

RESUMO

INTRODUCTION: Environmental factors have a key role in the control of gut microbiota and obesity. TLR2 knockout (TLR2-/-) mice in some housing conditions are protected from diet-induced insulin resistance. However, in our housing conditions these animals are not protected from diet-induced insulin-resistance. AIM: The aim of the present study was to investigate the influence of our animal housing conditions on the gut microbiota, glucose tolerance and insulin sensitivity in TLR2-/- mice. MATERIAL AND METHODS: The microbiota was investigated by metagenomics, associated with hyperinsulinemic euglycemic clamp and GTT associated with insulin signaling through immunoblotting. RESULTS: The results showed that TLR2-/- mice in our housing conditions presented a phenotype of metabolic syndrome characterized by insulin resistance, glucose intolerance and increase in body weight. This phenotype was associated with differences in microbiota in TLR2-/- mice that showed a decrease in the Proteobacteria and Bacteroidetes phyla and an increase in the Firmicutesphylum, associated with and in increase in the Oscillospira and Ruminococcus genera. Furthermore there is also an increase in circulating LPS and subclinical inflammation in TLR2-/-. The molecular mechanism that account for insulin resistance was an activation of TLR4, associated with ER stress and JNK activation. The phenotype and metabolic behavior was reversed by antibiotic treatment and reproduced in WT mice by microbiota transplantation. CONCLUSIONS: Our data show, for the first time, that the intestinal microbiota can induce insulin resistance and obesity in an animal model that is genetically protected from these processes.


Assuntos
Microbioma Gastrointestinal , Resistência à Insulina , Insulina/metabolismo , Receptor 2 Toll-Like/genética , Animais , Estresse do Retículo Endoplasmático , Deleção de Genes , Intolerância à Glucose/genética , Intolerância à Glucose/metabolismo , Intolerância à Glucose/microbiologia , Abrigo para Animais , Resistência à Insulina/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 2 Toll-Like/metabolismo
6.
Gene ; 718: 144073, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446096

RESUMO

Cell morphology of the oleaginous fungus, Aspergillus oryzae BCC7051, was genetically engineered by disruption of non-essential genes involved in cell wall biosynthesis. Comparative phenotypic analysis of two disruptant strains defective either in α-1,3-glucan synthase 1 (ΔAoAgs1) or chitin synthase B (ΔAoChsB), and the wild type showed that the ΔAoAgs1 strain had no alterations in colonial growth and sporulation when grown on agar medium whereas the ΔAoChsB disruptant showed growth retardation and lower sporulation. However, tiny and loose pellets were found in the ΔAoAgs1 culture grown in liquid medium, where fungal pellet size was decreased by 35-50% of the wild type size. Further investigation of the ΔAoAgs1 mutant grown under stress-induced conditions, including high salt concentration, ionic strength and osmolarity, showed that its growth and development remained similar to that of the wild type. When cultivating the ΔAoAgs1 strain in a stirred-tank bioreactor, lipid production in terms of titer and productivity was significantly improved. As compared to the wild type, an increase of triacylglycerol and ergosterol contents with a proportional decrease in steryl ester content was observed in the ΔAoAgs1 strain. These results suggest that the morphologically engineered strain of A. oryzae is a robust cell chassis useful for exploitation in further production development of functional lipids with industrial significance.


Assuntos
Aspergillus oryzae/metabolismo , Ergosterol/biossíntese , Engenharia Metabólica , Microrganismos Geneticamente Modificados/metabolismo , Triglicerídeos/biossíntese , Aspergillus oryzae/genética , Quitina Sintase/genética , Quitina Sintase/metabolismo , Ergosterol/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Deleção de Genes , Genes Fúngicos , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Microrganismos Geneticamente Modificados/genética , Triglicerídeos/genética
7.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(8): 773-776, 2019 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-31400125

RESUMO

OBJECTIVE: To discuss the value of chromosomal microarray analysis (CMA) for the identification of DMD gene deletions during prenatal diagnosis. METHODS: G-banded karyotyping and CMA were performed on fetuses with ultrasonographic soft markers but no family history for Duchenne/Becker muscular dystrophy (DMD/BMD). Denaturing high-performance liquid chromatograghy (DHPLC) was used to detect DMD gene mutations in umbilical cord blood and peripheral blood samples from the mothers. RESULTS: For fetus 1, analysis of amniocytes showed a normal karyotype, while CMA detected a 119 kb deletion at Xp21.1 (32 565 489 - 32 681 461), which encompassed exons 10 to 16 of the DMD gene. The result was confirmed by DHPLC analysis. The mother was found to have loss of heterozygosity in the same region. For fetus 2, karyotyping of amniocytes also showed a normal male karyotype, while CMA detected a 254 kb deletion at Xp21.1 (32 104 604 - 32 358 874), which encompassed exons 41 to 44 of the DMD gene. The same deletion was not detected in the mother. DHPLC analysis confirmed the presence of both deletions. CONCLUSION: Two fetuses harboring DMD gene deletions but without a family history were discovered. CMA can improve the efficiency for detecting single gene diseases caused by deletions.


Assuntos
Distrofina/genética , Deleção de Genes , Achados Incidentais , Análise em Microsséries , Distrofia Muscular de Duchenne/genética , Éxons , Feminino , Feto , Humanos , Masculino , Gravidez
8.
World J Microbiol Biotechnol ; 35(8): 127, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375931

RESUMO

Aeromonas hydrophila is a Gram-negative bacterium that causes serious infections in aquaculture and exhibits significant multidrug resistance. The LysR-type transcriptional regulator (LTTR) family proteins are a well-known group of transcriptional regulators involved in diverse physiological functions. However, the role of LTTRs in the regulation of bacterial resistance to antibiotics is still largely unknown. In this study, to further investigate the role of four putative LTTR family proteins (A0KIU1, A0KJ82, A0KPK0, and A0KQ63) in antibiotic resistance in A. hydrophila, their genes were cloned and overexpressed in engineered Escherichia coli. After the optimization of experimental conditions including incubation time, temperature, and IPTG concentration, these proteins were successfully purified, and their specific antibodies against mice were obtained. Using western blot analysis, we found that these LTTR family proteins were downregulated in A. hydrophila following antibiotic treatment, indicating that they may be involved in the regulation of antibiotic resistance. Additionally, minimum inhibitory concentration (MIC) assays of chloramphenicol (CM), chlortetracycline (CTC), ciprofloxacin (CF), furazolidone (FZ), and balofloxacin (BF) in E. coli showed that overexpression of these LTTRs led to increased sensitivity to several antibiotics. To further validate their functional role in antibiotic resistance, we demonstrated that bacteria with loss of A0KQ63 (ΔAHA_3980) exhibited multi-drug resistance properties. Our results indicate that these LTTR family proteins may play an important role in the antibiotic resistance of A. hydrophila, and the that underlying mechanisms controlling antibiotic resistance should be further investigated.


Assuntos
Aeromonas hydrophila/efeitos dos fármacos , Aeromonas hydrophila/genética , Farmacorresistência Bacteriana , Regulação Bacteriana da Expressão Gênica , Genes Reguladores , Fatores de Transcrição/metabolismo , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Western Blotting , Clonagem Molecular , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Deleção de Genes , Expressão Gênica , Perfilação da Expressão Gênica , Genes Bacterianos , Camundongos , Testes de Sensibilidade Microbiana , Fatores de Transcrição/análise , Fatores de Transcrição/genética
9.
Microbiol Res ; 228: 126304, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422235

RESUMO

Streptococcus suis (S. suis) is an important zoonotic pathogen that causes major economic losses in the pig industry worldwide. The S. suis cell division process is an integral part of its growth and reproduction, which is controlled by a complex regulatory network. Pyruvate dehydrogenase (PDH), which catalyzes the oxidative decarboxylation of pyruvate to form acetyl-CoA, while reducing NAD + to NADH, plays an important role in energy metabolism. Recently, we reported that pdh regulates virulence by reducing stress tolerance and biofilm formation in S. suis serotype 2. In this study, we found that deletion of the pdh gene in S. suis resulted in abnormal cell chains, plump morphology and abnormal localization of the Z rings, indicating that the knockout mutant is impaired in its ability to divide. In addition, the interaction between FtsZ and PDH in vitro was confirmed by ELISA, and qRT-PCR analysis revealed that the deletion of the pdh gene results in differential expression of the division-related genes ftsZ, ftsK, ftsl, zapA, divIC, pbp1a, rodA, mreD, and sepF. These results indicate that pdh is involved in the normal formation of Z rings and cell morphology during S. suis cell division.


Assuntos
Divisão Celular/genética , Divisão Celular/fisiologia , Complexo Piruvato Desidrogenase/genética , Streptococcus suis/citologia , Streptococcus suis/genética , Streptococcus suis/fisiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Proteínas do Citoesqueleto/genética , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus suis/patogenicidade , Suínos , Virulência , Fatores de Virulência/genética
10.
Genes Dev ; 33(17-18): 1252-1264, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31395740

RESUMO

Although MAX is regarded as an obligate dimerization partner for MYC, its function in normal development and neoplasia is poorly defined. We show that B-cell-specific deletion of Max has a modest effect on B-cell development but completely abrogates Eµ-Myc-driven lymphomagenesis. While Max loss affects only a few hundred genes in normal B cells, it leads to the global down-regulation of Myc-activated genes in premalignant Eµ-Myc cells. We show that the balance between MYC-MAX and MNT-MAX interactions in B cells shifts in premalignant B cells toward a MYC-driven transcriptional program. Moreover, we found that MAX loss leads to a significant reduction in MYC protein levels and down-regulation of direct transcriptional targets, including regulators of MYC stability. This phenomenon is also observed in multiple cell lines treated with MYC-MAX dimerization inhibitors. Our work uncovers a layer of Myc autoregulation critical for lymphomagenesis yet partly dispensable for normal development.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Linfoma/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Deleção de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Indóis/farmacologia , Cinurenina/genética , Cinurenina/metabolismo , Linfoma/fisiopatologia , Camundongos , Organoides/crescimento & desenvolvimento , Organoides/fisiopatologia , Oximas/farmacologia , Sulfonamidas/farmacologia
11.
Genes Dev ; 33(17-18): 1265-1279, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31395741

RESUMO

Chromosomal rearrangements of the mixed lineage leukemia (MLL) gene occur in ∼10% of B-cell acute lymphoblastic leukemia (B-ALL) and define a group of patients with dismal outcomes. Immunohistochemical staining of bone marrow biopsies from most of these patients revealed aberrant expression of BCL6, a transcription factor that promotes oncogenic B-cell transformation and drug resistance in B-ALL. Our genetic and ChIP-seq (chromatin immunoprecipitation [ChIP] combined with high-throughput sequencing) analyses showed that MLL-AF4 and MLL-ENL fusions directly bound to the BCL6 promoter and up-regulated BCL6 expression. While oncogenic MLL fusions strongly induced aberrant BCL6 expression in B-ALL cells, germline MLL was required to up-regulate Bcl6 in response to physiological stimuli during normal B-cell development. Inducible expression of Bcl6 increased MLL mRNA levels, which was reversed by genetic deletion and pharmacological inhibition of Bcl6, suggesting a positive feedback loop between MLL and BCL6. Highlighting the central role of BCL6 in MLL-rearranged B-ALL, conditional deletion and pharmacological inhibition of BCL6 compromised leukemogenesis in transplant recipient mice and restored sensitivity to vincristine chemotherapy in MLL-rearranged B-ALL patient samples. Oncogenic MLL fusions strongly induced transcriptional activation of the proapoptotic BH3-only molecule BIM, while BCL6 was required to curb MLL-induced expression of BIM. Notably, peptide (RI-BPI) and small molecule (FX1) BCL6 inhibitors derepressed BIM and synergized with the BH3-mimetic ABT-199 in eradicating MLL-rearranged B-ALL cells. These findings uncover MLL-dependent transcriptional activation of BCL6 as a previously unrecognized requirement of malignant transformation by oncogenic MLL fusions and identified BCL6 as a novel target for the treatment of MLL-rearranged B-ALL.


Assuntos
Regulação Leucêmica da Expressão Gênica , Proteína de Leucina Linfoide-Mieloide/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/fisiopatologia , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Animais , Biomarcadores Tumorais/genética , Sobrevivência Celular/genética , Células Cultivadas , Deleção de Genes , Marcação de Genes , Humanos , Camundongos , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Prognóstico , Regiões Promotoras Genéticas/genética
12.
Pan Afr Med J ; 32: 197, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31312309

RESUMO

Introduction: Just recently, it has been established that the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism is linked to the pathogenesis and to the evolution of human cancers. Therefore, the present study was concerned with the investigation of an eventual association between glioma and I/D polymorphism of the ACE gene. Methods: The expression of ACE gene was detected by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis in 36 Algerian patients with glioma and 195 healthy controls. Results: In glioma cases, allelic frequencies and genotypes distribution of the ACE I/D polymorphism were different from controls cases. ACE DD genotype were highly presented in glioma cases (63.9%) than controls (33.8%) and conferred 3.64-fold risk for predisposition in glioma cases (vs ID genotype, p<0.001). Recessive model (ACE II + ID genotypes vs DD) was associated with a 72% reduced risk of glioma (OR = 0.28, 95% CI: 0.13-0.60, p <0.001). Per copy D allele frequency was found higher in glioma cases (79.2%) than in controls (63.3 %), OR = 2.20, 95% CI: 1.20 - 4.03, p = 0.009. Conclusion: The obtained data showed that the presence of the D allele might be a risk factor for the development of glioma. Further studies considering different ethnic groups with large samples are required to confirm this finding.


Assuntos
Neoplasias Encefálicas/genética , Predisposição Genética para Doença , Glioma/genética , Peptidil Dipeptidase A/genética , Adulto , Argélia , Estudos de Casos e Controles , Feminino , Deleção de Genes , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutagênese Insercional , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Fatores de Risco
13.
Nat Commun ; 10(1): 2958, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273195

RESUMO

RNAi-based bone anabolic gene therapy has demonstrated initial success, but many practical challenges are still unmet. Here, we demonstrate that a recombinant adeno-associated virus 9 (rAAV9) is highly effective for transducing osteoblast lineage cells in the bone. The adaptor protein Schnurri-3 (SHN3) is a promising therapeutic target for osteoporosis, as deletion of shn3 prevents bone loss in osteoporotic mice and short-term inhibition of shn3 in adult mice increases bone mass. Accordingly, systemic and direct joint administration of an rAAV9 vector carrying an artificial-microRNA that targets shn3 (rAAV9-amiR-shn3) in mice markedly enhanced bone formation via augmented osteoblast activity. Additionally, systemic delivery of rAAV9-amiR-shn3 in osteoporotic mice counteracted bone loss and enhanced bone mechanical properties. Finally, we rationally designed a capsid that exhibits improved specificity to bone by grafting the bone-targeting peptide motif (AspSerSer)6 onto the AAV9-VP2 capsid protein. Collectively, our results identify a bone-targeting rAAV-mediated gene therapy for osteoporosis.


Assuntos
Reabsorção Óssea/complicações , Reabsorção Óssea/prevenção & controle , Osso e Ossos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Dependovirus/metabolismo , Inativação Gênica , Osteoporose/complicações , Animais , Reabsorção Óssea/patologia , Osso e Ossos/virologia , Capsídeo/metabolismo , Cartilagem/virologia , Modelos Animais de Doenças , Deleção de Genes , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Osteoblastos/metabolismo , Sorogrupo
14.
Vet Microbiol ; 235: 164-169, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282374

RESUMO

Marek's disease virus (MDV) is a highly contagious alphaherpesvirus that causes rapid onset of T cell lymphomas in chickens. MDV continues to break through vaccinal immunity due to the emergence of highly virulent field strains. Earlier studies revealed that deletion of the meq gene from MDV results in attenuated vaccines that protect against disease when chickens are infected with highly virulent strains. However, meq-deleted viruses still retain the ability to induce lymphoid organ atrophy, which raises safety concerns. In an earlier study, we found that deletion of lorf9 counteracts this lymphoid organ atrophy. Here, we describe the generation of a double deletion mutant virus lacking virus-encoded meq and lorf9. In vitro studies revealed that during replication, the mutant virus had kinetic characteristics similar to the parental virus; however, in vivo the replication capability was significantly reduced. Results of animal studies revealed no obvious MDV-specific symptoms and lesions. Importantly, the double deletion mutant virus lost the capacity to induce lymphoid organ atrophy, which has been the main obstacle during development of a good vaccine candidate.


Assuntos
Deleção de Genes , Herpesvirus Galináceo 1/genética , Herpesvirus Galináceo 1/patogenicidade , Tecido Linfoide/patologia , Doença de Marek/patologia , Proteínas Oncogênicas Virais/genética , Animais , Atrofia , Galinhas , Tecido Linfoide/virologia , Mutação , Doenças das Aves Domésticas/virologia , Replicação Viral
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(7): 690-695, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31315770

RESUMO

OBJECTIVE: To study the clinical features of acute lymphoblastic leukemia (ALL) in children with IKAROS family zinc finger 1 (IKZF1) deletion, and to observe the effect of increasing the intensity of chemotherapy on the prognosis of this disease. METHODS: A total of 278 children diagnosed with ALL between December 2015 and February 2018 were systematically treated according to the Chinese Children's Leukemia Group-ALL 2008 protocol (CCLG-ALL 2008). The patients were divided into an IKZF1-deleted group and a control group according to the presence or absence of IKZF1. The IKZF1-deleted group was treated with the regimen for high-risk group (HR) in the CCLG-ALL 2008 protocol, while the control group received different intensities of chemotherapy according to clinical risk classification. The clinical features and event-free survival rate (EFS) were compared between the two groups. RESULTS: A total of 24 (8.6%) cases of 278 children were found to have large deletions of exons of the IKZF1 gene. The IKZF1-deleted group had significantly higher proportions of cases with white blood cell count ≥50×109/L at initial diagnosis, BCR-ABL1 fusion gene positive, minimal residual disease ≥10% on the 15th day of induction remission treatment, minimal residual disease-high risk and clinical risk classification-high risk compared with the control group (P<0.05). The 3-year EFS rate (76%±10%) in the IKZF1-deleted group was lower than that in the control group (84%±4%), but with no significant difference between the two groups (P=0.282). The estimated 3-year EFS rate in the IKZF1-deleted-non-HR group (actually treated with the chemotherapy regimen for HR in the CCLG-ALL 2008 protocol) was 82%±12%, which was lower than that in the control-non-HR group (86%±5%), but there was no significant difference (P=0.436). CONCLUSIONS: ALL children with IKZF1 deletion have worse early treatment response, and increasing the intensity of chemotherapy might improve the prognosis.


Assuntos
Fator de Transcrição Ikaros/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras , Intervalo Livre de Doença , Deleção de Genes , Humanos , Neoplasia Residual , Prognóstico
16.
World J Microbiol Biotechnol ; 35(8): 115, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332542

RESUMO

Antibiotic and arsenic (As) contaminations are worldwide public health problems. Previously, the bacterial ABC-type efflux protein MacAB reportedly conferred resistance to macrolide-type antibiotics but not to other metal(loid)s. In this study, the roles of MacAB for the co-resistance of different antibiotics and several metal(loid)s were analyzed in Agrobacterium tumefaciens 5A, a strain resistant to arsenite [As(III)] and several types of antibiotics. The macA and macB genes were cotranscribed, and macB was deleted in A. tumefaciens 5A and heterologously expressed in Escherichia coli AW3110 and E. coli S17-1. Compared to the wild-type strain 5A, the macB deletion strain reduced bacterial resistance levels to several macrolide-type and penicillin-type antibiotics but not to cephalosporin-type antibiotics. In addition, the macB deletion strain showed lower resistance to As(III) but not to arsenate [As(V)], antimonite [Sb(III)] and cadmium chloride [Cd(II)]. The mutant strain 5A-ΔmacB cells accumulated more As(III) than the cells of the wild-type. Furthermore, heterologous expression of MacAB in E. coli S17-1 showed that MacAB was essential for resistance to macrolide, several penicillin-type antibiotics and As(III) but not to As(V). Heterologous expression of MacAB in E. coli AW3110 reduced the cellular accumulation of As(III) but not of As(V), indicating that MacAB is responsible for the efflux of As(III). These results demonstrated that, in addition to macrolide-type antibiotics, MacAB also conferred resistance to penicillin-type antibiotics and As(III) by extruding them out of cells. This finding contributes to a better understanding of the bacterial resistance mechanisms of antibiotics and metal(loid)s.


Assuntos
Agrobacterium tumefaciens/genética , Proteínas de Bactérias/genética , DNA Bacteriano/isolamento & purificação , Farmacorresistência Bacteriana Múltipla/genética , Macrolídeos/farmacologia , Agrobacterium tumefaciens/metabolismo , Arsenitos/farmacologia , Proteínas de Bactérias/metabolismo , Cefalosporinas/farmacologia , DNA Bacteriano/genética , Eritromicina/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Deleção de Genes , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Penicilinas/farmacologia
17.
Microbiol Res ; 226: 10-18, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284939

RESUMO

Microbial oxidation of antimonite [Sb(III)] to antimonate [Sb(V)] is a detoxification process which contributes to Sb(III) resistance. Antimonite oxidase AnoA is essential for Sb(III) oxidation, however, the regulation mechanism is still unknown. Recently, we found that the expressions of phosphate transporters were induced by Sb(III) using proteomics analysis in Agrobacterium tumefaciens GW4, thus, we predicted that the phosphate regulator PhoB may regulate bacterial Sb(III) oxidation and resistance. In this study, comprehensive analyses were performed and the results showed that (1) Genomic analysis revealed two phoB (named as phoB1 and phoB2) and one phoR gene in strain GW4; (2) Reporter gene assay showed that both phoB1 and phoB2 were induced in low phosphate condition (50 µM), but only phoB2 was induced by Sb(III); (3) Genes knock-out/complementation, Sb(III) oxidation and Sb(III) resistance tests showed that deletion of phoB2 significantly inhibited the expression of anoA and decreased bacterial Sb(III) oxidation efficiency and Sb(III) resistant. In contrast, deletion of phoB1 did not obviously affect anoA's expression level and Sb(III) oxidation/resistance; (4) A putative Pho motif was predicted in several A. tumefaciens strains and electrophoretic mobility shift assay (EMSA) showed that PhoB2 could bind with the promoter sequence of anoA; (5) Site-directed mutagenesis and short fragment EMSA revealed the exact DNA binding sequence for the protein-DNA interaction. These results showed that PhoB2 positively regulates Sb(III) oxidation and PhoB2 is also associated with Sb(III) resistance. Such regulation mechanism may provide a great contribution for bacterial survival in the environment with Sb and for bioremediation application.


Assuntos
Agrobacterium tumefaciens/metabolismo , Antimônio/metabolismo , Proteínas de Bactérias/metabolismo , Fosfatos/metabolismo , Agrobacterium tumefaciens/genética , Arsenitos/metabolismo , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana/fisiologia , Ensaio de Desvio de Mobilidade Eletroforética , Deleção de Genes , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes , Mutagênese Sítio-Dirigida , Oxirredução , Proteínas de Transporte de Fosfato/metabolismo , Proteômica
18.
Nat Commun ; 10(1): 2858, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253794

RESUMO

In bacterial tRNAs, 5-carboxymethoxyuridine (cmo5U) and its derivatives at the first position of the anticodon facilitate non-Watson-Crick base pairing with guanosine and pyrimidines at the third positions of codons, thereby expanding decoding capabilities. However, their biogenesis and physiological roles remained to be investigated. Using reverse genetics and comparative genomics, we identify two factors responsible for 5-hydroxyuridine (ho5U) formation, which is the first step of the cmo5U synthesis: TrhP (formerly known as YegQ), a peptidase U32 family protein, is involved in prephenate-dependent ho5U formation; and TrhO (formerly known as YceA), a rhodanese family protein, catalyzes oxygen-dependent ho5U formation and bypasses cmo5U biogenesis in a subset of tRNAs under aerobic conditions. E. coli strains lacking both trhP and trhO exhibit a temperature-sensitive phenotype, and decode codons ending in G (GCG and UCG) less efficiently than the wild-type strain. These findings confirm that tRNA hydroxylation ensures efficient decoding during protein synthesis.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Biossíntese de Proteínas/fisiologia , RNA de Transferência/metabolismo , Proteínas de Escherichia coli/genética , Evolução Molecular , Deleção de Genes , Regulação Bacteriana da Expressão Gênica/fisiologia , Filogenia , RNA Bacteriano
19.
Nature ; 571(7763): 72-78, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31217586

RESUMO

New antibiotics are needed to combat rising levels of resistance, with new Mycobacterium tuberculosis (Mtb) drugs having the highest priority. However, conventional whole-cell and biochemical antibiotic screens have failed. Here we develop a strategy termed PROSPECT (primary screening of strains to prioritize expanded chemistry and targets), in which we screen compounds against pools of strains depleted of essential bacterial targets. We engineered strains that target 474 essential Mtb genes and screened pools of 100-150 strains against activity-enriched and unbiased compound libraries, probing more than 8.5 million chemical-genetic interactions. Primary screens identified over tenfold more hits than screening wild-type Mtb alone, with chemical-genetic interactions providing immediate, direct target insights. We identified over 40 compounds that target DNA gyrase, the cell wall, tryptophan, folate biosynthesis and RNA polymerase, as well as inhibitors that target EfpA. Chemical optimization yielded EfpA inhibitors with potent wild-type activity, thus demonstrating the ability of PROSPECT to yield inhibitors against targets that would have eluded conventional drug discovery.


Assuntos
Antituberculosos/classificação , Antituberculosos/isolamento & purificação , Descoberta de Drogas/métodos , Deleção de Genes , Testes de Sensibilidade Microbiana/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Antituberculosos/farmacologia , DNA Girase/metabolismo , Resistência Microbiana a Medicamentos , Ácido Fólico/biossíntese , Terapia de Alvo Molecular , Mycobacterium tuberculosis/citologia , Mycobacterium tuberculosis/enzimologia , Ácidos Micólicos/metabolismo , Reprodutibilidade dos Testes , Bibliotecas de Moléculas Pequenas/classificação , Bibliotecas de Moléculas Pequenas/isolamento & purificação , Especificidade por Substrato , Inibidores da Topoisomerase II/isolamento & purificação , Inibidores da Topoisomerase II/farmacologia , Triptofano/biossíntese , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia
20.
Microbiol Res ; 223-225: 99-109, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178057

RESUMO

Streptococcus suis has received increasing attention for its involvement in severe infections in pigs and humans; however, their pathogenesis remains unclear. ClpX and ClpP, two subunits of the ATP-dependent caseinolytic protease Clp, play key roles in bacterial adaptation to various environmental stresses. In this study, a virulent S. suis serotype 2 strain, ZY05719, was employed to construct clpX and clpP deletion mutants (ΔclpX and ΔclpP, respectively) and their complementation strains. Both ΔclpX and ΔclpP displayed significantly reduced adaptability compared with the wild-type strain, evident through several altered phenotypes: formation of long cell chains, tendency to aggregate in culture, and reduced growth under acidic pH and H2O2-induced oxidative stress. ClpP and ClpX were required for the optimal growth during heat and cold stress, respectively. An in vitro experiment on RAW264.7 macrophage cells showed significantly increased sensitivity of ΔclpX and ΔclpP to phagocytosis compared with the wild-type strain. Mouse infection assays verified the deletion of clpX and clpP led to not only fewer clinical symptoms and lower mortality but also to a marked attenuation in bacterial colonization. These virulence-related phenotypes were restored by genetic complementation. Furthermore, the deletion of clpX or clpP caused a significant decrease in the expression of sodA, tpx, and apuA compared with the wild-type strain, suggesting that these genes may be regulated by ClpX and ClpP as downstream response factors to facilitate the bacterial tolerance against various environmental stresses. Taken together, these results suggest that ClpX and ClpP play important roles in stress tolerance for achieving the full virulence of S. suis serotype 2 during infection.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Proteínas de Bactérias/metabolismo , Endopeptidase Clp/metabolismo , Chaperonas Moleculares/metabolismo , Streptococcus suis/metabolismo , Streptococcus suis/patogenicidade , Animais , Proteínas de Bactérias/genética , Biofilmes , Resposta ao Choque Frio , Endopeptidase Clp/genética , Deleção de Genes , Regulação Bacteriana da Expressão Gênica , Resposta ao Choque Térmico , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Camundongos , Chaperonas Moleculares/genética , Pressão Osmótica , Estresse Oxidativo , Fagocitose , Células RAW 264.7 , Infecções Estreptocócicas/microbiologia , Streptococcus suis/genética , Streptococcus suis/crescimento & desenvolvimento , Transcriptoma , Virulência/genética , Fatores de Virulência/genética , Fatores de Virulência/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA