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1.
Micromachines (Basel) ; 13(10)2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36296100

ABSTRACT

A new synthetic strategy has been developed for the facile fabrication of a N-doped porous carbon (NC-800) material via a facile carbonization of functionalized poly(vinylidene fluoride) (PVDF). The prepared NC-800 exhibits good specific capacitance of 205 F/g at 1 A/g and cycle stability (95.2% retention after 5000 cycles at 1 A/g). The adsorption capacity of NC-800 on methylene blue and methyl orange was 780 mg/g and 800 mg/g, respectively. The facile and economical method and good performance (supercapacitor and adsorption) suggest that the NC-800 is a promising material for energy storage and adsorption.

2.
J Am Chem Soc ; 143(8): 3054-3059, 2021 03 03.
Article in English | MEDLINE | ID: mdl-33570385

ABSTRACT

Herein, we report that, by using chiral bicyclic bisborane catalysts, we have achieved the first highly regio-, diastereo-, and enantioselective direct asymmetric vinylogous Mannich reactions of acyclic α,ß-unsaturated ketones. The strong Lewis acidity and steric bulk of the bisborane catalysts were essential for the observed high yields and selectivities.

3.
Zookeys ; 973: 123-151, 2020.
Article in English | MEDLINE | ID: mdl-33110375

ABSTRACT

Eight species of the genus Nephrotoma were previously known to occur in Xizang Autonomous Region. Here, three species are added to the fauna of Xizang. Among them two species, N. beibengensis sp. nov. and N. hanae sp. nov. are described and illustrated as new to science, and one species, N. evittata Alexander, 1935 is recorded from Xizang for the first time. The following four species are redescribed: N. claviformis Yang & Yang, 1987, N. didyma Yang & Yang, 1987, N. nigrohalterata Edwards, 1928, and N. xizangensis Yang & Yang, 1987. A key to the species of Nephrotoma from Xizang is presented.

4.
Zootaxa ; 4524(2): 200-212, 2018 Nov 21.
Article in English | MEDLINE | ID: mdl-30486121

ABSTRACT

Three new species of Zaischnopsis Ashmead from southern China, Z. candetibia Peng sp. nov., Z. fumosa Peng Xiang sp. nov. and Z. nivalinota Peng Xiang sp. nov., are described and illustrated based on females. The only other species of Zaischnopsis recorded from China, Z. tubatius (Walker) is redescribed and illustrated in detail, and the species are differentiated in a key that includes all Zaischnopsis species recorded from the Oriental region.


Subject(s)
Hymenoptera , Animals , China , Female
5.
Ecotoxicol Environ Saf ; 166: 336-344, 2018 Dec 30.
Article in English | MEDLINE | ID: mdl-30278395

ABSTRACT

Cadmium (Cd) is a pervasive carcinogen and environmental endocrine disruptor. We studied the changes in learning and memory of offspring mice, whose mothers were exposed to 10 mg Cd/L via the drinking water during pregnancy and lactation period, as well as the changes of testosterone and estrogen levels, serum Cd levels, the histopathological changes and the changes in the mRNA and protein levels of different subunits of γ-aminobutyric acid receptor subtype A subunits (GABAARs) in the hippocampus at the prepuberty, puberty, young adult, and adult stages. At birth, Cd had no obvious effect on mice offspring as statistically accessed based on their body weight, body length, and tail length (all p > 0.05). After grouped, the serum Cd levels increased in the three exposed groups more than in the normal control group at stages (all p < 0.05). Only serum estradiol of female offspring at age 7 weeks was significantly decreased compared with other groups (all p < 0.05). Histopathological results showed that the arrangement of the cells in hippocampal CA1 area of mice offspring was significantly sparse in the exposed groups compared with the control group. At 5 and 7 weeks, two Cd-exposed groups showed prolonged escape latency and exploring time for the platform compared with the normal group in the Morris water maze (all p < 0.05). Only increased protein expression of GABAARα5 was found in the Cd group at these two ages. At age 12 weeks, similar impaired learning and memory of female mice, and decreased protein expression of GABAARδ was found in Cd-exposed groups. Collectively, low-dose Cd had no effect on the growth of mice offspring but affected their learning and memory, especially female offspring, at puberty, young adulthood, and adulthood through changed structure in the hippocampal CA1 area and protein expression of GABAARα5 and GABAARδ.


Subject(s)
Cadmium/toxicity , Carcinogens/toxicity , Environmental Pollutants/toxicity , Maze Learning/drug effects , Memory/drug effects , Animals , Body Weight/drug effects , Cadmium/metabolism , Disease Models, Animal , Estrogens/metabolism , Female , Hippocampus/drug effects , Male , Mice , Pregnancy , Protein Subunits/drug effects , Receptors, GABA/metabolism , Receptors, GABA-A/metabolism , Sexual Maturation/drug effects , Testosterone/metabolism
6.
Mol Carcinog ; 56(4): 1312-1321, 2017 04.
Article in English | MEDLINE | ID: mdl-27859625

ABSTRACT

Osteosarcoma (OS) remains one deadly disease for many affected patients. MicroRNAs (miRNAs) are thought to have an important role in tumor metastasis by regulating diverse cellular pathways. Here, we describe the function and regulation network of miR-489-3p in osteosarcoma (OS) metastasis. MiR-489-3p expression was downregulated in OS cells especially in high metastatic potential cells and was also significantly decreased in metastatic lesions compared with their corresponding primary tumor samples. Both gain- and loss-of-function studies confirmed that miR-489-3p significantly suppressed OS cell invasion and metastasis both in vitro and in vivo. Mechanistically, paired box gene 3 (PAX3) was identified as a functional target of miR-489-3p in OS cells. MiR-489-3p inhibited OS metastasis by negatively regulating expression of PAX3. In addition, PAX3 expression was markedly higher in OS tissues than in adjacent non-cancerous tissues. Transwell assays and in vivo metastasis assays demonstrated that overexpression of PAX3 significantly promoted the invasiveness and pulmonary metastasis of OS cells. On the other hand, downregulation of PAX3 markedly reduced cell metastatic potential. Mechanistic investigations indicated that prometastasis function of PAX3 was mediated by upregulating downstream target MET tyrosine kinase receptor. In conclusion, our results reveal that miR-489-3p-PAX3-MET signaling is critical to OS metastasis. Targeting the pathway described here may open new therapeutic prospects to restrict the metastatic potential of OS. © 2016 Wiley Periodicals, Inc.


Subject(s)
Bone Neoplasms/genetics , Bone and Bones/pathology , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , Osteosarcoma/genetics , PAX3 Transcription Factor/genetics , Proto-Oncogene Proteins c-met/genetics , Animals , Bone Neoplasms/pathology , Cell Line, Tumor , Down-Regulation , Humans , Male , Mice, Inbred BALB C , MicroRNAs/analysis , Neoplasm Invasiveness/genetics , Neoplasm Invasiveness/pathology , Neoplasm Metastasis/genetics , Neoplasm Metastasis/pathology , Osteosarcoma/pathology , PAX3 Transcription Factor/analysis , Proto-Oncogene Proteins c-met/analysis , Signal Transduction
7.
Oncotarget ; 7(30): 47431-47443, 2016 Jul 26.
Article in English | MEDLINE | ID: mdl-27329727

ABSTRACT

High expression of cancer stem cell (CSC) markers is related to poor prognosis of patients with hepatocellular carcinoma (HCC). However, the expression of these markers in patient-derived xenograft (PDX) models and the relationship of the expression levels of these markers between HCC patients and their PDX models at subsequent low passages are unclear. To investigate the prognostic impact of putative CSC markers in patients with HCC and in related PDX models, the expression of CD133, CD90, CD44, ALDH1, CK7, CK19, OCT4, SOX2, vimentin, nestin, CD13 and EpCam were assessed by quantitative reverse transcription-PCR (qRT-PCR) and then were validated using immunohistochemistry in tumor or peritumoral tissues from patients and tumor tissues from PDX models. Cumulative survival analysis of the patients and animals was conducted using the Kaplan-Meier method and the log-rank test. Only the expression levels of CD133 and CD44 were higher in tumor tissues than in the peritumoral tissues of HCC patients by qRT-PCR. High consistency of the prognostic value of the expression of CD133/CD44 was observed in HCC patients and the PDX models. High expression levels of CD133 and CD44 were positively related to the poor prognosis of HCC patients and to that in the PDX models. PDX HCC models in the present study have been suggested to be predictive of disease outcome, which could shed light on personalized medicine and the mechanisms of CSC marker expression on prognosis.


Subject(s)
AC133 Antigen/analysis , Carcinoma, Hepatocellular/mortality , Hyaluronan Receptors/analysis , Liver Neoplasms/mortality , Neoplastic Stem Cells/chemistry , Adult , Aged , Animals , Carcinoma, Hepatocellular/pathology , Female , Humans , Liver Neoplasms/pathology , Male , Mice , Mice, SCID , Middle Aged , Neoplasm Transplantation , Prognosis , Transplantation, Heterologous
8.
Clin Res Hepatol Gastroenterol ; 39(5): 627-36, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26066297

ABSTRACT

OBJECTIVE: Association of Signal transducers and activators of transcription-4 (STAT4) gene polymorphism with susceptibility to inflammatory bowel disease have been investigated in a number of epidemiological studies, but the results are inclusive. The aim of this meta-analysis was to more precisely estimate the relationship. METHODS: The databases of Pubmed and CBM updated to October, 2014 were retrieved. Random- or fixed-effect model was used to estimate odd radio (OR) and corresponding 95% confidence interval (95%CI) on the basis of heterogeneity. RESULTS: Seven articles containing 2196 Crohn's disease (CD) cases, 1588 ulcerative colitis (UC) cases and 4126 controls were identified. We detected a significant association between STAT4 rs7574865 polymorphism and IBD susceptibility in overall population (GG vs. GT+TT, OR=0.855, 95% CI=0.760-0.962, P=0.009), but not in Caucasian and Asian population, respectively. No association was detected between rs7574865 polymorphism and CD susceptibility in overall, Asian and Caucasian population, respectively. Interestingly, a significant association was detected between rs7574865 with UC susceptibility in overall population (G vs. T, OR=0.881, 95% CI=0.798-0.972, P=0.012; GG vs. GT+TT, OR=0.788, 95% CI=0.679-0.914, P=0.002; GG vs. TT, OR=0.683, 95% CI=0.498-0.937, P=0.018) and Caucasians (GG vs. GT+TT, OR=0.833, 95% CI=0.701-0.990, P=0.038; GG+GT vs. TT, OR=0.667, 95% CI=0.456-0.975, P=0.037; GG vs. TT, OR=0.636, 95% CI=0.433-0.934, P=0.021), respectively, and a possible association was found in Asian population (GG vs. GT+TT, OR=0.709, 95% CI=0.503-0.998, P=0.049). CONCLUSIONS: STAT4 rs7574865 gene is IBD risk factor, and this gene polymorphism is associated with UC susceptibility, especially in Caucasians. To confirm these findings, further studies with more sample size are required for a definitive conclusion.


Subject(s)
Asian People/genetics , Genetic Predisposition to Disease , Inflammatory Bowel Diseases/genetics , Polymorphism, Single Nucleotide/genetics , STAT4 Transcription Factor/genetics , White People/genetics , Biomarkers/blood , China/epidemiology , Colitis, Ulcerative/genetics , Crohn Disease/genetics , Evidence-Based Medicine , Humans , Inflammatory Bowel Diseases/diagnosis , Inflammatory Bowel Diseases/ethnology , Predictive Value of Tests , Risk Factors , Sensitivity and Specificity
9.
Clin Nutr Res ; 4(2): 104-9, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25954731

ABSTRACT

To investigate the possible risk factors related to macrosomia. Pregnant women and their newborns (n = 1041) were recruited from a cohort study in Maternal and Child Care Center of Hefei from January 2011 to July 2012. Questionnaires were applied to collect the demographic data besides the medical records. Detailed health records of the entire pregnancy were obtained using retrospective study. Meanwhile the data of neonatal outcomes was prospectively tracked. Associations between exposure risk factors and macrosomia were analyzed using Pearson's chi squared test. Logistic regression models were used to assess the independent association between these potential predictors and macrosomia. The incidence of macrosomia of this cohort was 11.24% of which male: female = 2.55:1. Male incidence (8.07%) of macrosomia was higher than female (3.17%), p < 0.001. Body mass index (BMI) before pregnancy (pre-BMI), maternal height, parity were not independently associated with macrosomia; multiple logistic regression analysis indicated that macrosomia was mainly independently associated with weight gain in pregnancy (OR=1.14, 95% CI [1.10-1.19]), maternal age (OR = 1.09, 95% CI [1.03-1.15]) and gestational age (OR = 1.62, 95% CI [1.31-1.99]), respectively. Our findings indicate that weight gain in pregnancy, maternal age and gestational age should be considered as independent risk factors for macrosomia.

10.
Int Psychogeriatr ; 27(9): 1429-38, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25851548

ABSTRACT

BACKGROUND: The etiology and pathogenesis of neurodegenerative disorders has yet to be elucidated, so their differential diagnosis is a challenge. This is especially true in differentiating Alzheimer's disease (AD), dementia with Lewy bodies (DLB), Parkinson disease (PD), and multiple system atrophy (MSA). METHODS: A total of 11 eligible articles were identified by search of electronic databases including PubMed, Springer Link, Elsevier, and the Cochrane Library, up to June 2014. In meta-analyses, standardized mean differences (SMD), with 95% confidence intervals (CI), comparing cerebrospinal fluid (CSF) measures of α-synuclein between the above conditions were calculated using random-effects models. RESULTS: CSF α-synuclein concentrations were significantly higher in AD compared to DLB [SMD: 0.32, 95% CI: (0.02, 0.62), z = 2.07, P = 0.038]; PD [SMD: 0.87, 95% CI: (0.15, 1.58), z = 2.38, P = 0.017]; or MSA [SMD: 1.14, 95% CI: (0.15, 2.14), z = 2.25, P = 0.025]. However, no significant difference was found between patients with AD and neurological cognitively normal controls [SMD: 0.02, 95% CI: (-0.21, 0.24), z = 0.13, P = 0.894]. CONCLUSIONS: Results of these meta-analysis suggest that quantification of CSF α-synuclein could help distinguish AD from other neurodegenerative disorders such as DLB, PD, or MSA.


Subject(s)
Alzheimer Disease/cerebrospinal fluid , Lewy Body Disease/cerebrospinal fluid , Multiple System Atrophy/cerebrospinal fluid , Parkinson Disease/cerebrospinal fluid , alpha-Synuclein/cerebrospinal fluid , Alzheimer Disease/diagnosis , Diagnosis, Differential , Humans , Lewy Body Disease/diagnosis , Multiple System Atrophy/diagnosis , Parkinson Disease/diagnosis
11.
Asia Pac J Clin Nutr ; 23(3): 429-36, 2014.
Article in English | MEDLINE | ID: mdl-25164454

ABSTRACT

Variation of plasma free amino acids (PFAAs) is an essential feature of protein metabolic abnormalities in cancer patients. But there still little data about the cancer tissue free amino acid (TFAAs) profiles, including their patterns and correlations with PFAAs. To evaluate the variation in PFAAs and cancer TFAAs in patients with lung cancer, including their patterns and correlations, we investigated the concentrations of free amino acids in lung cancer tissues (n=27), paired lung paracarcinomous tissues (n=27) and plasma (n=27) using an automatic amino acid analyzer after pre-treatment. Within the PFAAs, the concentrations of five amino acids (tryptophan, glycine, citrulline, ornithine and proline) were significantly decreased, while that of phenylalanine was markedly increased compared with control subjects. Within the TFAAs, the concentrations of three amino acids (taurine, glutamic acid and glycine) were increased, while the concentrations of two amino acids (lysine and ornithine) were decreased significantly in lung cancer tissues compared with the paracarcinomous tissues. The amino acid patterns in PFAAs and TFAAs had similar trends, but percentage variations were diverse. Additionally, the concentrations of five amino acids (lysine, phenylalanine, threonine, serine, and alanine) in PFAAs correlated with those in lung cancer TFAAs, but no amino acids in PFAAs were correlated with those in lung paracarcinomous TFAAs. Thus, PFAA profiles may reflect the status of cancer tissues, which may provide more information about the metabolic statuses and prognoses of patients with lung cancer.


Subject(s)
Amino Acids/metabolism , Lung Neoplasms/metabolism , Amino Acids/blood , Female , Humans , Lung Neoplasms/blood , Male , Middle Aged
12.
PLoS Pathog ; 10(3): e1003949, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24603905

ABSTRACT

Most plant viruses are transmitted by hemipteroid insects. Some viruses can be transmitted from female parent to offspring usually through eggs, but the mechanism of this transovarial transmission remains unclear. Rice stripe virus (RSV), a Tenuivirus, transmitted mainly by the small brown planthopper (Laodelphax striatellus), is also spread to the offspring through the eggs. Here, we used the RSV-planthopper system as a model to investigate the mechanism of transovarial transmission and demonstrated the central role of vitellogenin (Vg) of L. striatellus in the process of virus transmission into the eggs. Our data showed Vg can bind to pc3 in vivo and in vitro and colocalize in the germarium. RSV filamentous ribonucleoprotein particles (RNPs) only accumulated in the terminal filaments and pedicel areas prior to Vg expression and was not present in the germarium until Vg was expressed, where RSV RNPs and Vg had colocalized. Observations by immunoelectron microscopy (IEM) also indicated that these two proteins colocalized in nurse cells. Knockdown of Vg expression due to RNA interference resulted in inhibition of the invasion of ovarioles by RSV. Together, the data obtained indicated that RSV RNPs may enter the nurse cell of the germarium via endocytosis through binding with Vg. Finally, the virus enters the oocytes through nutritive cords, using the same route as for Vg transport. Our results show that the Vg of L. striatellus played a critical role in transovarial transmission of RSV and shows how viruses can use existing transovarial transportation systems in insect vectors for their own purposes.


Subject(s)
Flowers/virology , Insect Vectors/metabolism , Oryza/virology , Tenuivirus/pathogenicity , Vitellogenins/metabolism , Animals , Fluorescent Antibody Technique , Hemiptera/virology , Immunoprecipitation , Microscopy, Immunoelectron , Real-Time Polymerase Chain Reaction , Two-Hybrid System Techniques
13.
J Virol ; 88(8): 4265-74, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24478421

ABSTRACT

UNLABELLED: Rice ragged stunt virus (RRSV), an oryzavirus in the family Reoviridae, is transmitted by the brown planthopper, Nilaparvata lugens, in a persistent-propagative manner. Here, we established a continuous cell line of brown planthopper to investigate the mechanism underlying the formation of the viroplasm, the putative site for viral replication and assembly, during infection of RRSV in its insect vector cells. Within 24 h of viral infection of cultured cells, the viroplasm had formed and contained the viral nonstructural proteins Pns6 and Pns10, known to be constituents of viroplasm. Core capsid protein P3, core particles, and newly synthesized viral RNAs were accumulated inside the viroplasm, while outer capsid protein P8 and virions were accumulated at the periphery of the viroplasm, confirming that the viroplasm induced by RRSV infection was the site for viral replication and assembly. Pns10 formed viroplasm-like inclusions in the absence of viral infection, suggesting that the viroplasm matrix was largely composed of Pns10. Pns6 was recruited in the viroplasm by direct interaction with Pns10. Core capsid protein P3 was recruited to the viroplasm through specific association with Pns6. Knockdown of Pns6 and Pns10 expression using RNA interference inhibited viroplasm formation, virion assembly, viral protein expression, and viral double-stranded RNA synthesis. Thus, the present study shows that both Pns6 and Pns10 of RRSV play important roles in the early stages of viral life cycle in its insect vector cells, by recruiting or retaining components necessary for viral replication and assembly. IMPORTANCE: The brown planthopper, a commonly distributed pest of rice in Asia, is the host of numerous insect endosymbionts, and the major vector of two rice viruses (RRSV and rice grassy stunt virus). For the first time, we successfully established the continuous cell line of brown planthopper. The unique uniformity of brown planthopper cells in the monolayer can support a consistent, synchronous infection by endosymbionts or viral pathogens, improving our understanding of molecular insect-microbe interactions.


Subject(s)
Insect Vectors/virology , Reoviridae/physiology , Virus Cultivation/methods , Virus Replication , Animals , Cell Culture Techniques , Cells, Cultured , Hemiptera/virology , Reoviridae/growth & development , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism
14.
Front Microbiol ; 4: 206, 2013.
Article in English | MEDLINE | ID: mdl-23888157

ABSTRACT

Rice gall dwarf virus (RGDV), a member of the family Reoviridae, causes repeated epidemics in rice fields in southern China. An RGDV isolate collected from Guangdong Province (southern China) is mainly transmitted by leafhopper vector Recilia dorsalis in a persistent-propagative manner. The infection by RGDV induces the formation of virus-containing tubules in the plant host and insect vector. In this study, we established continuous cell cultures of the leafhopper R. dorsalis to investigate the functional role of these tubules within the insect vector. Cytopathologic studies revealed that the tubules, which comprised viral non-structural protein Pns11 and contained viral particles, were able to protrude from the surface of cultured leafhopper cells. Tubule-like structures formed in non-host insect cells after the expression of Pns11 in a baculovirus system, suggesting that Pns11 was the minimal viral factor required for the formation of the tubules induced by RGDV infection. In cultured leafhopper cells, knockdown of Pns11 expression from RNA interference, induced by synthesized dsRNA from the Pns11 gene, abolished the formation of such tubules, preventing the direct cell-to-cell spread of RGDV without significant effects on viral multiplication. All these results show that RGDV exploits virus-containing tubules to facilitate viral spread among its insect vector cells.

15.
J Gen Virol ; 94(Pt 6): 1421-1425, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23468422

ABSTRACT

A cell line from the small brown planthopper (SBPH; Laodelphax striatellus) was established to study replication of rice stripe virus (RSV), a tenuivirus. The SBPH cell line, which had been subcultured through 30 passages, formed monolayers of epithelial-like cells. Inoculation of cultured vector cells with RSV resulted in a persistent infection. During viral infection in the SBPH cell line, the viral non-structural protein NS3 co-localized with the filamentous ribonucleoprotein particles of RSV, as revealed by electron and confocal microscopy. The knockdown of NS3 expression due to RNA interference induced by synthesized double-stranded RNAs from the NS3 gene significantly inhibited viral infection in the SBPH cell line. These results demonstrated that NS3 of RSV might be involved in viral replication or assembly. The persistent infection of the SBPH cell line by RSV will enable a better understanding of the complex relationship between RSV and its insect vector.


Subject(s)
Hemiptera/virology , Insect Vectors/virology , Plant Diseases/virology , Tenuivirus/physiology , Virus Replication , Animals , Cell Line , Plant Diseases/parasitology , RNA, Viral/genetics , RNA, Viral/metabolism , Tenuivirus/genetics , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism
16.
PLoS Pathog ; 8(11): e1003032, 2012.
Article in English | MEDLINE | ID: mdl-23166500

ABSTRACT

Rice dwarf virus (RDV) replicates in and is transmitted by a leafhopper vector in a persistent-propagative manner. Previous cytopathologic and genetic data revealed that tubular structures, constructed by the nonstructural viral protein Pns10, contain viral particles and are directly involved in the intercellular spread of RDV among cultured leafhopper cells. Here, we demonstrated that RDV exploited these virus-containing tubules to move along actin-based microvilli of the epithelial cells and muscle fibers of visceral muscle tissues in the alimentary canal, facilitating the spread of virus in the body of its insect vector leafhoppers. In cultured leafhopper cells, the knockdown of Pns10 expression due to RNA interference (RNAi) induced by synthesized dsRNA from Pns10 gene strongly inhibited tubule formation and prevented the spread of virus among insect vector cells. RNAi induced after ingestion of dsRNA from Pns10 gene strongly inhibited formation of tubules, preventing intercellular spread and transmission of the virus by the leafhopper. All these results, for the first time, show that a persistent-propagative virus exploits virus-containing tubules composed of a nonstructural viral protein to traffic along actin-based cellular protrusions, facilitating the intercellular spread of the virus in the vector insect. The RNAi strategy and the insect vector cell culture provide useful tools to investigate the molecular mechanisms enabling efficient transmission of persistent-propagative plant viruses by vector insects.


Subject(s)
Arthropod Vectors/virology , Plant Diseases/virology , Plant Viruses/metabolism , Viral Nonstructural Proteins/metabolism , Animals , Arthropod Vectors/genetics , Arthropod Vectors/metabolism , Cell Line , Insecta , Plant Viruses/genetics , Plant Viruses/pathogenicity , Plant Viruses/ultrastructure , Viral Nonstructural Proteins/genetics
17.
Virus Res ; 167(2): 404-8, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22683297

ABSTRACT

Southern rice black-streaked dwarf virus (SRBSDV), a fijivirus, is transmitted by the white-backed planthopper in a persistent-propagative manner. In this study, we found that another planthopper species, the small brown planthopper (SBPH), could acquire SRBSDV but not transmit it. To identify the transmission barrier for SRBSDV in SBPHs, sequential infection by SRBSDV in the organs of SBPHs was studied with immunofluorescence for viral antigens. SRBSDV initially entered the epithelial cells of the midgut, then viroplasms, the sites for viral replication, formed in the midgut of viruliferous SBPHs. Furthermore, SRBSDV spread within the midgut, but failed to disseminate from the midgut into the hemocoel or into the salivary glands. All these results indicated that the inability of SBPH to transmit SRBSDV could be due to the restriction of viral dissemination from the midgut of SBPH, which led to the failure of viral spread to the salivary glands for virus transmission.


Subject(s)
Disease Vectors , Hemiptera/virology , Plant Diseases/virology , Reoviridae/growth & development , Reoviridae/pathogenicity , Animals , Gastrointestinal Tract/virology , Oryza/virology
18.
J Virol ; 86(10): 5800-7, 2012 May.
Article in English | MEDLINE | ID: mdl-22398296

ABSTRACT

An in vitro culture system of primary cells from white-backed planthopper, an insect vector of Southern rice black-streaked dwarf virus (SRBSDV), a fijivirus, was established to study replication of the virus. Viroplasms, putative sites of viral replication, contained the nonstructural viral protein P9-1, viral RNA, outer-capsid proteins, and viral particles in virus-infected cultured insect vector cells, as revealed by transmission electron and confocal microscopy. Formation of viroplasm-like structures in non-host insect cells upon expression of P9-1 suggested that the matrix of viroplasms observed in virus-infected cells was composed basically of P9-1. In cultured insect vector cells, knockdown of P9-1 expression due to RNA interference (RNAi) induced by synthesized double-stranded RNA (dsRNA) from the P9-1 gene strongly inhibited viroplasm formation and viral infection. RNAi induced by ingestion of dsRNA strongly abolished viroplasm formation, preventing efficient viral spread in the body of intact vector insects. All these results demonstrated that P9-1 was essential for viroplasm formation and viral replication. This system, combining insect vector cell culture and RNA interference, can further advance our understanding of the biological activities of fijivirus replication proteins.


Subject(s)
Cell Culture Techniques/methods , Genetic Techniques , Hemiptera/virology , RNA Interference , Reoviridae/physiology , Viral Proteins/metabolism , Virus Replication , Animals , Cell Culture Techniques/instrumentation , Genetic Techniques/instrumentation , Oryza/virology , Plant Diseases/virology , Reoviridae/genetics , Spodoptera , Viral Proteins/genetics
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