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1.
Arch Virol ; 166(10): 2881-2885, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34338875

RESUMO

Here, we describe a novel mycovirus, tentatively designated as "Botryosphaeria dothidea mitovirus 3" (BdMV3), isolated from Botryosphaeria dothidea strain FJ, which causes pear ring rot disease in Fujian Province, China. The complete genome nucleotide sequence of BdMV3 is 2538 nt in length and contains a single 2070-nt open reading frame (ORF) encoding a putative RNA-dependent RNA polymerase (RdRp) of 689 amino acids (aa) using the fungal mitochondrial genetic code. BLASTp analysis revealed that the RdRp of BdMV3 shares 28.91%-69.36% sequence identity (query sequence coverage more than 90%) with those of members of the genus Mitovirus, with the highest sequence identity of 69.36% and 68.79% to the corresponding RdRp aa sequences of Rhizoctonia solani mitovirus 10 and Macrophomina phaseolina mitovirus 4, respectively. Phylogenetic analysis based on RdRp aa sequences indicated that BdMV3 is a new member of the genus Mitovirus in the family Mitoviridae.


Assuntos
Ascomicetos/virologia , Genoma Viral/genética , Doenças das Plantas/microbiologia , Pyrus/microbiologia , Vírus de RNA/genética , Sequência de Aminoácidos , China , Micovírus/classificação , Micovírus/genética , Fases de Leitura Aberta/genética , Filogenia , Vírus de RNA/classificação , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética
2.
Cell Rep ; 36(1): 109314, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34233190

RESUMO

MED20 is a non-essential subunit of the transcriptional coactivator Mediator complex, but its physiological function remains largely unknown. Here, we identify MED20 as a substrate of the anti-obesity CRL4-WDTC1 E3 ubiquitin ligase complex through affinity purification and candidate screening. Overexpression of WDTC1 leads to degradation of MED20, whereas depletion of WDTC1 or CUL4A/B causes accumulation of MED20. Depleting MED20 inhibits adipogenesis, and a non-degradable MED20 mutant restores adipogenesis in WDTC1-overexpressing cells. Furthermore, knockout of Med20 in preadipocytes abolishes development of brown adipose tissues. Removing one allele of Med20 in preadipocytes protects mice from diet-induced obesity and reverses weight gain in Cul4a- or Cul4b-depleted mice. Chromatin immunoprecipitation sequencing (ChIP-seq) analysis reveals that MED20 organizes the early adipogenic complex by bridging C/EBPß and RNA polymerase II to promote transcription of the central adipogenic factor, PPARγ. Our findings have thus uncovered a critical role of MED20 in promoting adipogenesis, development of adipose tissue and diet-induced obesity.

3.
Mol Plant Pathol ; 22(10): 1271-1287, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34288324

RESUMO

A novel cytorhabdovirus, tentatively named Actinidia virus D (AcVD), was identified from kiwifruit (Actinidia chinensis) in China using high-throughput sequencing technology. The genome of AcVD consists of 13,589 nucleotides and is organized into seven open reading frames (ORFs) in its antisense strand, coding for proteins in the order N-P-P3-M-G-P6-L. The ORFs were flanked by a 3' leader sequence and a 5' trailer sequence and are separated by conserved intergenic junctions. The genome sequence of AcVD was 44.6%-51.5% identical to those of reported cytorhabdoviruses. The proteins encoded by AcVD shared the highest sequence identities, ranging from 27.3% (P6) to 44.5% (L), with the respective proteins encoded by reported cytorhabdoviruses. Phylogenetic analysis revealed that AcVD clustered together with the cytorhabdovirus Wuhan insect virus 4. The subcellular locations of the viral proteins N, P, P3, M, G, and P6 in epidermal cells of Nicotiana benthamiana leaves were determined. The M protein of AcVD uniquely formed filament structures and was associated with microtubules. Bimolecular fluorescence complementation assays showed that three proteins, N, P, and M, self-interact, protein N plays a role in the formation of cytoplasm viroplasm, and protein M recruits N, P, P3, and G to microtubules. In addition, numerous paired proteins interact in the nucleus. This study presents the first evidence of a cytorhabdovirus infecting kiwifruit plants and full location and interaction maps to gain insight into viral protein functions.

4.
Cells ; 10(4)2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33920690

RESUMO

Citrus tristeza virus is a member of the genus Closterovirus in the family Closteroviridae. The p23 of citrus tristeza virus (CTV) is a multifunctional protein and RNA silencing suppressor. In this study, we identified a p23 interacting partner, FK506-binding protein (FKBP) 17-2, from Citrus aurantifolia (CaFKBP17-2), a susceptible host, and Nicotiana benthamiana (NbFKBP17-2), an experimental host for CTV. The interaction of p23 with CaFKBP17-2 and NbFKBP17-2 were individually confirmed by yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. Subcellular localization tests showed that the viral p23 translocated FKBP17-2 from chloroplasts to the plasmodesmata of epidermal cells of N. benthamiana leaves. The knocked-down expression level of NbFKBP17-2 mRNA resulted in a decreased CTV titer in N. benthamiana plants. Further, BiFC and Y2H assays showed that NbFKBP17-2 also interacted with the coat protein (CP) of CTV, and the complexes of CP/NbFKBP17-2 rapidly moved in the cytoplasm. Moreover, p23 guided the CP/NbFKBP17-2 complexes to move along the cell wall. To the best of our knowledge, this is the first report of viral proteins interacting with FKBP17-2 encoded by plants. Our results provide insights for further revealing the mechanism of the CTV CP protein movement.

5.
J Transl Med ; 19(1): 163, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882954

RESUMO

BACKGROUND: Cigarette smoking constitutes a major lifestyle risk factor for osteoporosis and hip fracture. It is reported to impair the outcome of many clinical procedures, such as wound infection treatment and fracture healing. Importantly, although several studies have already demonstrated the negative correlation between cigarette consume and impaired bone homeostasis, there is still a poor understanding of how does smoking affect bone health, due to the lack of an adequately designed animal model. Our goal was to determine that cigarette smoke exposure impairs the dynamic bone remodeling process through induction of bone resorption and inhibition of bone formation. METHODS: We developed cigarette smoke exposure protocols exposing mice to environmental smoking for 10 days or 3 months to determine acute and chronic smoke exposure effects. We used these models, to demonstrate the effect of smoking exposure on the cellular and molecular changes of bone remodeling and correlate these early alterations with subsequent bone structure changes measured by microCT and pQCT. We examined the bone phenotype alterations in vivo and ex vivo in the acute and chronic smoke exposure mice by measuring bone mineral density and bone histomorphometry. Further, we measured osteoclast and osteoblast differentiation gene expression levels in each group. The function changes of osteoclast or osteoblast were evaluated. RESULTS: Smoke exposure caused a significant imbalance between bone resorption and bone formation. A 10-day exposure to cigarette smoke sufficiently and effectively induced osteoclast activity, leading to the inhibition of osteoblast differentiation, although it did not immediately alter bone structure as demonstrated in mice exposed to smoke for 3 months. Cigarette smoke exposure also induced DNA-binding activity of nuclear factor kappaB (NFκB) in osteoclasts, which subsequently gave rise to changes in bone remodeling-related gene expression. CONCLUSIONS: Our findings suggest that smoke exposure induces RANKL activation-mediated by NFκB, which could be a "smoke sensor" for bone remodeling.


Assuntos
NF-kappa B , Fumar , Animais , Remodelação Óssea , Inflamação , Camundongos , Fumaça , Fumar/efeitos adversos
6.
J Nurs Manag ; 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33794045

RESUMO

AIM: This study aimed to (1) assess the current status of Chinese nurses' exposure to workplace violence; (2) identify the cluster of interrelationships between abusive supervision, anxiety and depression symptoms, work ability, and workplace violence in nursing settings; and (3) clarify the functional mechanism among these variables. METHODS: A cross-sectional survey was conducted online from September to October 2020 in China. A total of 1,221 valid questionnaires were collected across 100 cities in 31 provinces. RESULTS: Approximately 67.57% of participants experienced workplace violence in the past one year, in the types of verbal violence (59.71%), made difficulties (43.16%), mobbing behaviour (26.70%), smear reputation (22.52%), physical violence (11.30%), intimidating behaviour (10.16%) and sexual harassment (4.10%), respectively. Moreover, nurses' exposure to workplace violence was significantly and positively influenced by the perceptions of abusive supervision (ß = 0.209, p < .01) and the symptoms of anxiety and depression (ß = 0.328, p < .01). Anxious and depressive symptoms partly mediated the association between abusive supervision and workplace violence, which were significantly moderated by work ability (ß = -0.021, p < .05). CONCLUSIONS: Our study assesses the prevalence of the seven types of workplace violence against Chinese nurses. Majority of nurses have experienced different types of workplace violence. Nurses who are abused by their supervisor are more likely to develop poor psychological health than those who are not. Moreover, nurses' positive association of abusive supervision with workplace violence is more notable among nurses with lower work ability. IMPLICATIONS OF NURSING MANAGEMENT: 'No abusive supervision, no workplace violence'. A harmonious nursing environment needs to be provided to minimize exposure to workplace violence and mental health threats towards nursing staff, which is a key point for hospital administrators and health policymakers. Essential work ability should be developed to reduce the damage of the abusive supervision and workplace violence against nurses.

7.
ISME J ; 15(7): 1893-1906, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33531623

RESUMO

Fungi are generally thought to live in host plants with a single lifestyle, being parasitism, commensalism, or mutualism. The former, known as phytopathogenic fungi, cause various plant diseases that result in significant losses every year; while the latter, such as endophytic fungi, can confer fitness to the host plants. It is unclear whether biological factors can modulate the parasitic and mutualistic traits of a fungus. In this study, we isolated and characterized a mycovirus from an endophytic strain of the fungus Pestalotiopsis theae, a pathogen of tea (Camellia sinensis). Based on molecular analysis, we tentatively designated the mycovirus as Pestalotiopsis theae chrysovirus-1 (PtCV1), a novel member of the family Chrysoviridae, genus Alphachrysovirus. PtCV1 has four double-stranded (ds) RNAs as its genome, ranging from 0.9 to 3.4 kbp in size, encapsidated in isometric particles. PtCV1 significantly reduced the growth rates of its host fungus in vitro (ANOVA; P-value < 0.001) and abolished its virulence in planta (ANOVA; P-value < 0.001), converting its host fungus to a non-pathogenic endophyte on tea leaves, while PtCV1-free isolates were highly virulent. Moreover, the presence of PtCV1 conferred high resistance to the host plants against the virulent P. theae strains. Here we report a mycovirus that modulates endophytic and phytopathogenic fungal traits and provides an alternative approach to biological control of plant diseases caused by fungi.


Assuntos
Micovírus , Vírus de RNA , Micovírus/genética , Fungos/genética , Doenças das Plantas , Plantas , Vírus de RNA/genética
8.
Viruses ; 13(1)2020 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375657

RESUMO

Chinese jujube (Ziziphus jujuba Mill.) is a native fruit crop in China. Leaf mottle and dapple fruit disease is prevalent in cultivated jujube plants grown at Aksu in Xinjiang Uygur Autonomous Region of China. Jujube yellow mottle-associated virus (JYMaV), a tentative member in the genus Emaravirus, was recently identified from mottle-diseased jujube plants grown in Liaoning Province in China, but its incidence and genetic diversity in China is unknown. In this study, the genome sequences of three JYMaV isolates from two jujube cultivars and one jujube variant were determined by high-throughput sequencing (HTS) for small RNA and rRNA-depleted RNA coupled with RT-PCR assays. Comparison of these sequences together with sequences of the viral RNA segments derived by primer set 3C/5H-based RT-PCR revealed that genetic diversity was present in the virus populations and high sequence variation occurred at the non-translational regions of each of the viral genomic segments. Field investigation confirmed the close association of the virus with leaf mottle symptoms of jujube plants. Furthermore, this study revealed that P5 encoded in the viral RNA5 displayed a nuclear localization feature differing from the plasmodesma (PD) subcellular localization of the virus movement protein (P4), and the two proteins could interact with each other in the BiFC assays. Our study provides a snapshot of JYMaV genetic diversity in its natural hosts.


Assuntos
Bunyaviridae/classificação , Bunyaviridae/genética , Ziziphus/virologia , Bunyaviridae/isolamento & purificação , Bunyaviridae/ultraestrutura , China , Variação Genética , Genoma Viral , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta , Fenótipo , Filogenia , Doenças das Plantas/virologia , Folhas de Planta/virologia , Vírus de RNA/genética , RNA Viral , Análise de Sequência de RNA
9.
Plant Dis ; 104(11): 2786-2798, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32997610

RESUMO

Pear chlorotic leaf spot (PCLS) is a recently emerged disease of commercially cultivated sandy pear (Pyrus pyrifolia) trees in central and southern China. By integrating high-throughput sequencing and conventional Sanger sequencing of reverse-transcription (RT)-PCR products, a novel emaravirus infecting pear trees was identified and molecularly characterized. The virus was provisionally named pear chlorotic leaf spot-associated virus (PCLSaV). PCLSaV shows the typical molecular features of members of the genus Emaravirus in the family Fimoviridae. It has a genome composed of at least five negative-sense RNA segments, with each containing a single open reading frame and two complementary 13-nucleotide stretches at the 5' and 3' termini. PCLSaV shows a close phylogenetic relationship with recognized emaraviruses but forms a separate clade. Moreover, double-membrane-bound bodies were observed in PCLSaV-infected tissues and in extracts of PCLSaV-infected leaves. For the first time, our study revealed the profile distribution of viral RNA reads from the RNA-seq libraries of three samples along the RNA1 to RNA5 of an emaravirus. Field surveys combined with specific RT-PCR assays revealed the presence of PCLSaV in almost all PCLS-diseased pear samples, strongly supporting the association of the virus with the PCLS disease. This study revealed the first emaravirus infecting pear trees and its association with a severe pear chlorotic leaf disease.


Assuntos
Pyrus , China , Filogenia , Doenças das Plantas , Vírus Satélites
10.
Genome Res ; 30(8): 1097-1106, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32759226

RESUMO

Although mammalian genomes are diploid, previous studies extensively investigated the average chromatin architectures without considering the differences between homologous chromosomes. We generated Hi-C, ChIP-seq, and RNA-seq data sets from CD4 T cells of B6, Cast, and hybrid mice, to investigate the diploid chromatin organization and epigenetic regulation. Our data indicate that inter-chromosomal interaction patterns between homologous chromosomes are similar, and the similarity is highly correlated with their allelic coexpression levels. Reconstruction of the 3D nucleus revealed that distances of the homologous chromosomes to the center of nucleus are almost the same. The inter-chromosomal interactions at centromere ends are significantly weaker than those at telomere ends, suggesting that they are located in different regions within the chromosome territories. The majority of A|B compartments or topologically associated domains (TADs) are consistent between B6 and Cast. We found 58% of the haploids in hybrids maintain their parental compartment status at B6/Cast divergent compartments owing to cis effect. About 95% of the trans-effected B6/Cast divergent compartments converge to the same compartment status potentially because of a shared cellular environment. We showed the differentially expressed genes between the two haploids in hybrid were associated with either genetic or epigenetic effects. In summary, our multi-omics data from the hybrid mice provided haploid-specific information on the 3D nuclear architecture and a rich resource for further understanding the epigenetic regulation of haploid-specific gene expression.

11.
Arch Virol ; 165(7): 1667-1670, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32328855

RESUMO

In this study, we report the molecular characterization of a novel positive-sense single-stranded RNA (+ssRNA) mycovirus from Botryosphaeria dothidea strain G91, which we name "Botryosphaeria dothidea botourmiavirus 1" (BdBOV-1). The complete genome of BdBOV-1 is 2547 nucleotides (nt) long, contains one open reading frame (ORF) potentially encoding an RNA-dependent RNA polymerase (RdRp), and shows a close relationship to mycoviruses of the family Botourmiaviridae. Phylogenetic analysis based on the RdRp sequences confirmed that BdBOV-1 clustered together with the members of the family Botourmiaviridae. To the best of our knowledge, this is the first report of a +ssRNA mycovirus infecting B. dothidea.


Assuntos
Ascomicetos/virologia , Micovírus/genética , Micovírus/isolamento & purificação , Vírus de RNA/isolamento & purificação , Ascomicetos/fisiologia , Micovírus/classificação , Genoma Viral , Fases de Leitura Aberta , Filogenia , Doenças das Plantas/microbiologia , Vírus de RNA/classificação , Vírus de RNA/genética , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
12.
Medicine (Baltimore) ; 99(11): e19544, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32176108

RESUMO

The relationship between coronary artery disease (CAD) and low serum 25-hydroxyvitamin D (25(OH)D) levels has emerged. Postmenopausal (PM) women are at increased risk of CAD and vitamin D (VitD) deficiency.To investigate the relationship between CAD and VitD levels in PM women.This case-control study included 93 consecutive female patients aged 50 to 79 years old undergoing coronary angiography for evaluation of CAD and 119 age-matched controls. Serum 25(OH)D concentrations were classed as adequate (serum 25(OH)D: ≥20 ng/mL); insufficient (serum 25(OH)D: 10 to <20 ng/mL); and deficient (serum 25(OH)D: <10 ng/mL). Major cardiovascular risk factors were also explored.CAD occurred in 67/127 (52.8%) patients with VitD deficiency; 21/66 (31.8%) patients that were VitD insufficient; and in 5/19 (26.3%) patients with adequate VitD levels. Multivariate regression analysis suggested that a deficiency of VitD increased CAD (odds ratio = 2.891; 95% confidence interval = 1.459-7.139, P < .001).VitD deficiency should be evaluated in PM women as a possible cause of CAD.


Assuntos
Doença da Artéria Coronariana/epidemiologia , Pós-Menopausa , Deficiência de Vitamina D/complicações , Idoso , Estudos de Casos e Controles , China/epidemiologia , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/complicações , Feminino , Humanos , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue
13.
Plant Methods ; 16: 9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32025236

RESUMO

Background: Cucurbits produce fruits or vegetables that have great dietary importance and economic significance worldwide. The published genomes of at least 11 cucurbit species are boosting gene mining and novel breeding strategies, however genetic transformation in cucurbits is impractical as a tool for gene function validation due to low transformation efficiency. Virus-induced gene silencing (VIGS) is a potential alternative tool. So far, very few ideal VIGS vectors are available for cucurbits. Results: Here, we describe a new VIGS vector derived from cucumber green mottle mosaic virus (CGMMV), a monopartite virus that infects cucurbits naturally. We show that the CGMMV vector is competent to induce efficient silencing of the phytoene desaturase (PDS) gene in the model plant Nicotiana benthamiana and in cucurbits, including watermelon, melon, cucumber and bottle gourd. Infection with the CGMMV vector harboring PDS sequences of 69-300 bp in length in the form of sense-oriented or hairpin cDNAs resulted in photobleaching phenotypes in N. benthamiana and cucurbits by PDS silencing. Additional results reflect that silencing of the PDS gene could persist for over two months and the silencing effect of CGMMV-based vectors could be passaged. Conclusions: These results demonstrate that CGMMV vector could serve as a powerful and easy-to-use tool for characterizing gene function, controlling viral pathogens or even performing resistance breeding in cucurbits. Moreover, this study will possess considerable important reference value for developing different viral vectors.

14.
Virus Res ; 275: 197736, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31626876

RESUMO

Viruses in the genus Emaravirus contain 5-8 negative genomic RNAs and cause severe diseases of plants. In this study, a novel emaravirus, provisionally named Actinidia emaravirus 2 (AcEV-2), was identified from a kiwifruit tree showing leaf mottle and chlorosis symptoms. The genome of AcEV-2 consisted of at least six RNAs (RNAs 1-6) with sizes of 7079, 2252, 1387, 1514, 1744 and 1233 nucleotides (nts), respectively. Proteins encoded by RNAs1-4 of AcEV-2 shared the highest amino acid (aa) sequence identities of 62.2%-77.3% with the corresponding proteins of fig mosaic emaravirues (FMV) and pigeonpea sterility mosaic emaravirus 2 (PPSMV-2). Whilst, the P5 and P6 encoded by AcEV-2 exhibited the highest identities of 44.2% and 39.2% with the corresponding proteins of PPSMV-2. It was the second emaravirus infecting Actinidia trees in China. Preliminary virus detection disclosed the presence of AcEV-2 in three Actinidia species grown in three provinces in the central and southern China.


Assuntos
Actinidia/virologia , Doenças das Plantas/virologia , Vírus de RNA/classificação , Proteínas Virais/genética , China , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Vírus de RNA/isolamento & purificação , RNA Viral/genética
15.
BMC Genomics ; 20(1): 1015, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31878887

RESUMO

BACKGROUND: CCCTC-Binding Factor (CTCF), also known as 11-zinc finger protein, participates in many cellular processes, including insulator activity, transcriptional regulation and organization of chromatin architecture. Based on single cell flow cytometry and single cell RNA-FISH analyses, our previous study showed that deletion of CTCF binding site led to a significantly increase of cellular variation of its target gene. However, the effect of CTCF on genome-wide landscape of cell-to-cell variation remains unclear. RESULTS: We knocked down CTCF in EL4 cells using shRNA, and conducted single cell RNA-seq on both wild type (WT) cells and CTCF-Knockdown (CTCF-KD) cells using Fluidigm C1 system. Principal component analysis of single cell RNA-seq data showed that WT and CTCF-KD cells concentrated in two different clusters on PC1, indicating that gene expression profiles of WT and CTCF-KD cells were systematically different. Interestingly, GO terms including regulation of transcription, DNA binding, zinc finger and transcription factor binding were significantly enriched in CTCF-KD-specific highly variable genes, implying tissue-specific genes such as transcription factors were highly sensitive to CTCF level. The dysregulation of transcription factors potentially explains why knockdown of CTCF leads to systematic change of gene expression. In contrast, housekeeping genes such as rRNA processing, DNA repair and tRNA processing were significantly enriched in WT-specific highly variable genes, potentially due to a higher cellular variation of cell activity in WT cells compared to CTCF-KD cells. We further found that cellular variation-increased genes were significantly enriched in down-regulated genes, indicating CTCF knockdown simultaneously reduced the expression levels and increased the expression noise of its regulated genes. CONCLUSIONS: To our knowledge, this is the first attempt to explore genome-wide landscape of cellular variation after CTCF knockdown. Our study not only advances our understanding of CTCF function in maintaining gene expression and reducing expression noise, but also provides a framework for examining gene function.


Assuntos
Fator de Ligação a CCCTC/deficiência , Fator de Ligação a CCCTC/genética , Técnicas de Silenciamento de Genes , RNA-Seq , Análise de Célula Única , Animais , Linhagem Celular Tumoral , Camundongos
16.
Viruses ; 11(9)2019 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-31450668

RESUMO

The severe strain of citrus tristeza virus (CTV) causes quick decline of citrus trees. However, the CTV mild strain causes no symptoms and commonly presents in citrus trees. Viral suppressor of RNA silencing (VSR) plays an important role in the successful invasion of viruses into plants. For CTV, VSR has mostly been studied in severe strains. In this study, the N4 mild strain in China was sequenced and found to have high sequence identity with the T30 strain. Furthermore, we verified the functions of three VSRs in the N4 strain, and p23 was found to be the most effective in terms of local silencing suppressor activity among the three CTV VSRs and localized to both nucleus and plasmodesmata, which is similar to CTV T36 strain. Several conserved amino acids were identified in p23. Mutation of E95A/V96A and M99A/L100AA impaired p23 protein stability. Consequently, these two mutants lost most of its suppressor activity and their protein levels could not be rescued by co-expressing p19. Q93A and R143A/E144A abolished p23 suppressor activity only and their protein levels increased to wild type level when co-expressed with p19. This work may facilitate a better understanding of the pathogenic mechanism of CTV mild strains.


Assuntos
Citrus/virologia , Closterovirus/genética , Interações Hospedeiro-Patógeno/genética , Proteínas Virais/genética , Closterovirus/patogenicidade , Genoma Viral , Mutação , Doenças das Plantas/virologia , Interferência de RNA
17.
Fungal Biol ; 123(9): 669-675, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31416586

RESUMO

The fungus causing target spot disease, Corynespora cassiicola (Berk. & M. A. Curtis) C. T. Wei, poses an increasing threat to watermelon (Citrullus lanatus), muskmelon (Cucumis melo), and cucumber (Cucumis sativus); the most economically important cucurbit crops grown in China. An understanding of the molecular mechanisms underlying the pathogenicity of C. cassiicola is essential for the development of new strategies to control this disease-causing fungus. Agrobacterium tumefaciens-mediated transformation (ATMT) might be useful to obtain transformants of C. cassiicola, for the ultimate identification of genes involved in pathogenicity. In the present work, we established and optimized an ATMT protocol using A. tumefaciens strain AGL-1 carrying the vector pATMT1 for C. cassiicola. Efficiency of ATMT was 102-148 transformants per 106 conidia and successive subculturing of transformants on non-selective and selective media demonstrated that the integrated transfer (T)-DNA was stably inherited in C. cassiicola transformants. The integration of the hygromycin B phosphotransferase (hph) gene into C. cassiicola was validated by PCR and Southern blot analyses, which revealed that nearly 90 % of the transformants contained single-copy T-DNA. The transformants with altered phenotypes were characterized. Three of these transformants completely lost pathogenicity and other three showed strongly impaired pathogenicity relative to the Cc-GX strain on muskmelon leaves. These results strongly suggest that ATMT may be used as a molecular tool for identifying genes relevant to pathogenicity in the fungus C. cassiicola, an emerging threat to several agronomically important plants in China.


Assuntos
Agrobacterium tumefaciens/genética , Ascomicetos/genética , Transformação Genética , Agrobacterium tumefaciens/fisiologia , Ascomicetos/patogenicidade , Ascomicetos/fisiologia , China , Cucumis melo/microbiologia , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Proteínas Fúngicas/genética , Mutagênese Insercional , Doenças das Plantas/microbiologia , Virulência
18.
Viruses ; 11(6)2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167478

RESUMO

Banana trees, citrus fruit trees, pome fruit trees, grapevines, mango trees, and stone fruit trees are major fruit trees cultured worldwide and correspond to nearly 90% of the global production of woody fruit trees. In light of the above, the present manuscript summarizes the viruses that infect the major fruit trees, including their taxonomy and morphology, and highlights selected viruses that significantly affect fruit production, including their genomic and biological features. The results showed that a total of 163 viruses, belonging to 45 genera classified into 23 families have been reported to infect the major woody fruit trees. It is clear that there is higher accumulation of viruses in grapevine (80/163) compared to the other fruit trees (each corresponding to less than 35/163), while only one virus species has been reported infecting mango. Most of the viruses (over 70%) infecting woody fruit trees are positive-sense single-stranded RNA (+ssRNA), and the remainder belong to the -ssRNA, ssRNA-RT, dsRNA, ssDNA and dsDNA-RT groups (each corresponding to less than 8%). Most of the viruses are icosahedral or isometric (79/163), and their diameter ranges from 16 to 80 nm with the majority being 25-30 nm. Cross-infection has occurred in a high frequency among pome and stone fruit trees, whereas no or little cross-infection has occurred among banana, citrus and grapevine. The viruses infecting woody fruit trees are mostly transmitted by vegetative propagation, grafting, and root grafting in orchards and are usually vectored by mealybug, soft scale, aphids, mites or thrips. These viruses cause adverse effects in their fruit tree hosts, inducing a wide range of symptoms and significant damage, such as reduced yield, quality, vigor and longevity.


Assuntos
Frutas/virologia , Vírus de Plantas , Árvores/virologia , Citrus/virologia , Classificação , Genes Virais , Genoma Viral , Malus/virologia , Mangifera/virologia , Musa/virologia , Filogenia , Doenças das Plantas/virologia , Vírus de Plantas/classificação , Vírus de Plantas/genética , Vírus de Plantas/isolamento & purificação , Vírus de Plantas/ultraestrutura , Prunus avium/virologia , Prunus domestica/virologia , Vitis/virologia
19.
Rev Invest Clin ; 71(3): 204-210, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31184336

RESUMO

Background: Osteoporosis (OP) is common in patients with chronic obstructive pulmonary disease (COPD). The relationship between OP and COPD has been primarily studied in male patients, and few reports are available in postmenopausal women. Objective: The purpose of this study was to investigate the association between bone mineral density (BMD) and COPD in postmenopausal women. Methods: This cross-sectional study included 133 clinically stable female ex-smokers with confirmed COPD, and 31 age-matched "ex-smoker" female controls. We analyzed groups according to their airway obstruction category. BMD was measured on dual-energy X-ray absorptiometry images of the left femoral neck. Results: Patients with COPD had lower T-scores and higher prevalence of osteopenia/OP than the control group. In the COPD group, the airway obstruction category was significantly associated with the T-score after adjustment for confounders. Multivariate logistic regression analysis showed COPD was an independent marker for increased risk of osteopenia/OP in postmenopausal women. Conclusions: COPD and airway obstruction category were strongly related to BMD. Postmenopausal women with COPD, especially those with severe airway obstruction, had a higher prevalence rate and a higher risk of osteopenia and OP than female controls without COPD.


Assuntos
Densidade Óssea/fisiologia , Osteoporose Pós-Menopausa/epidemiologia , Pós-Menopausa , Doença Pulmonar Obstrutiva Crônica/complicações , Absorciometria de Fóton , Idoso , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/fisiopatologia , Doenças Ósseas Metabólicas/epidemiologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Prevalência , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fatores de Risco
20.
J Cancer Res Clin Oncol ; 145(8): 1999-2012, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31172267

RESUMO

BACKGROUND: The processes of prostate cancer (PCa) invasion and metastasis are facilitated by proteolytic cascade involving multiple proteases, such as matrix metalloproteinases, serine proteases and cysteine proteases including cathepsin K (CatK). CatK is predominantly secreted by osteoclasts and specifically degrades collagen I leading to bone destruction. PCa and breast cancer preferentially metastasize to the bone. Importantly, CatK expression level is greater in PCa bone metastatic sites compared to primary tumor and normal prostate tissues. However, the underlying mechanism of CatK during PCa metastases into the bone remains to be elucidated. We investigated the functional role of CatK during the PCa establishment and growth process in the murine bone. METHODS: CatK mRNA expression was validated by RT-PCR, protein expression by immunoblotting in PCa LNCaP, C4-2B, and PC3 cells as well as in PCa tissues. Its protein production was measured using ELISA assay. The effect of both knockdowns via siRNA and CatK inhibitor was compared in regard to PCa cell invasion. We further studied the dose-dependent CatK inhibitor effect on conditioned media-induced bone resorption. In setting up an animal model, C4-2B cells were injected into the tibiae of SCID mice. The animals treated with either vehicle or CatK inhibitor for 8 weeks at the time of tumor cell injection (tumor establishment model; protocol I) or 4 weeks after tumor cell injection (tumor progression model; protocol II) were applied to histological and histomorphometric analyses. RESULTS: We confirmed CatK expression in PCa LNCaP, C4-2B, and PC3 cells as well as in PCa tissues. Furthermore, we observed the inhibitory effects of a selective CatK inhibitor on PCa cell invasion. The CatK inhibitor dose-dependently inhibited PCa-conditioned media-induced bone resorption. Upon injection of C4-2B cells into the tibiae of SCID mice, the selective CatK inhibitor significantly prevented the tumor establishment in protocol I, and reduced the tumor growth in bone in protocol II. It also decreased serum PSA levels in both animal models. The inhibitory effects of the CatK inhibitor were enhanced in combination with zoledronic acid (ZA). CONCLUSION: The selective CatK inhibitor may prevent the establishment and progression of PCa in bone, thus making it a novel therapeutic approach for advanced PCa.


Assuntos
Neoplasias Ósseas/prevenção & controle , Neoplasias Ósseas/secundário , Catepsina K/antagonistas & inibidores , Terapia de Alvo Molecular/métodos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Inibidores de Proteases/uso terapêutico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Neoplasias Ósseas/genética , Catepsina K/genética , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Masculino , Camundongos , Camundongos SCID , Células PC-3 , Neoplasias da Próstata/genética , Inibidores de Proteases/farmacologia , RNA Interferente Pequeno/farmacologia , RNA Interferente Pequeno/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
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