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91.
Martin M.T. Glie B. 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(5):427-431
Plum pox potyvirus (PPV) induces in infected Nicotiana clevelandii cells characteristic crystalline inclusions known as nuclear inclusions (NI) when located in the nucleus and as dense material (Dm) when located in the cytoplasm. Crystalline inclusions contain protease (NIa) and RNA-dependent RNA polymerase (NIb) proteins. It is now well established for all potyviruses that cylindrical inclusions contain CI helicase ATPase protein (Martin et al., 1992). The intracellular location of other non-structural PPV proteins remains unknown. Using Escherichia coli expression vectors, specific antibodies were obtained against P1, P3, 6K2 and NIb PPV proteins for which antibodies were not yet available. As expected, NIb antiserum labelled crystalline inclusions. P1, P3 and 6K2 proteins were present in both types of crystalline inclusions found in the nucleus and in the cytoplasm of PPV-infected leaves of N. clevelandii, suggesting that nuclear inclusions and dense material were composed of the same proteins. This composition is discussed. 相似文献
92.
B.C. Lee Y.K. He K. Murao M. Isogai G. Dahal I. Uyeda 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(6):493-499
Rice dwarf virus isolates were collected from several locations in Japan, the Philippines, China, Nepal and Korea. Genomic dsRNA segment profiles in polyacrylamide gel electrophoresis differed among the isolates. There were less differences in the profiles between isolates from Japan and Korea than in those between these two Countries and others. Nucleic acid hybridization was used to examine the extent of genomic variation. Full-length cDNAs to all genomic segments encoding non-structural proteins (S4, S6, S9, S10, S11 and S12) were synthesized from two Japanese isolates, and were used for dot-blot hybridization. Hybridizations using probes generated from the full-length cDNA clones failed to differentiate isolates from different geographical areas. However, cDNA probes covering a variable region of S12 were able to distinguish Japanese and Korean isolates from those of other countries. Phylogenetic tree analysis based on the amino acid sequence of P12 encoded by S12 grouped Japanese and Korean isolates together. The Chinese isolates from two different locations (Yunnan and Fujian) were closely related to each other, and were the most distantly related to Japanese and Korean isolates. 相似文献
93.
Y. Antignus M. Lapidot N. Ganaim J. Cohen O. Lachman M. Pearlsman B. Raccah A. Gera 《Phytoparasitica》1997,25(4):319-330
Received April 24, 1997; received in final form June 29, 1997. Symptoms resembling tomato spotted wilt virus (TSWV) infections
were documented among ornamental and vegetable crops in commercial greenhouses and open fields in Israel. Plants exhibiting
these symptoms were collected from January 1992 to December 1996. Among cultivated plants analyzed for TSWV by enzyme-linked
immunosorbent assay (ELISA), 19 species representing five families were found to be infected; natural infection was also recorded
in six plant species of weeds. Virus identity was characterized by host range, serology and electron microscopy. Serological
reaction with the isolates, found in Israel, using antisera from different sources as well as the sequence analysis of the
nucleocapsid gene, demonstrated that the Israeli isolates of TSWV are a member of tospovirus serogroup I, type I (BR-01 strain).
No virus transmission was found in seeds collected from virus-infected vegetable and ornamental crops. A non-radioactive molecular
probe derived from the cloned nucleocapsid isolate enables specific detection of the virus in crude sap from infected plants.
The detection of TSWV in Israel constitutes a severe potential threat to the ornamental and vegetable industry. 相似文献
94.
95.
采用圆点印迹法检测GFkV,结果表明:Tris-HCl和PBS在提取GFkV时效果相同,在带毒葡萄植株中韧皮部的GFkV含量较高。 相似文献
96.
DING Gui-xia ZHANG Ai-hua HUANG Song-ming WU Yuan-jun FEI Li GUO Mei CHEN Rong-hua 《园艺学报》2004,20(10):1754-1758
AIM: To investigate the role of NF-κB/IκB signal pathway in the regulation of cyclooxygenase-2 (COX-2) expression in human mesangial cells (HMC). METHODS: The PGE2 concentration in supernatants of HMC was measured by radioimmunoassay. COX-2 mRNA and protein expression were determined by RT-PCR and Western blot. Electrophoretic mobility shift assay (EMSA) and Western blot were used to detect the activity of NF-κB and degradation of IκB. RESULTS: IL-1β significantly upregulated COX-2 expression and PGE2 production in HMC. Significant up-regulation of NF-κB activation, nuclear translocation of p65 subunit, and degradation of IκB α and IκB β were observed in IL-1β-induced HMC. CONCLUSION: Expression of COX-2 in IL-1β-induced HMC is mediated by NF-κB/IκB signal pathway. 相似文献
97.
AIM: To investigate the effect of sodium nitroprusside (SNP) on activation of nuclear factor κB. METHODS: The techniques of culture of human T lymphocytes, Western blot and RT-PCR were applied. The effects of NO donor sodium nitroprusside (SNP) at different concentrations on mRNA and protein expression of IκBα in human T lymphocytes at 30 min or 120 min after stimulating with phytohaemagglutinin (PHA-P) were observed. RESULTS: SNP at middle or high concentrations reduced the degradation of κIBαprotein 30 min after stimulating with PHA-P,and increased the re-expression of κIBαmRNA 120 min after stimulating with PHA-P significantly.CONCLUSION: The mechanism of inhibitory effect of SNP at middle or high concentrations may be due to the decrease in degradation and the increase in re-synthesis of κIBα.The regulatory mechanism of SNP at low concentration may not be through κIBα. 相似文献
98.
AIM: To study the effect of propolis on the expression of CD54 and activation of NF-κB p65 in lung tissue of acute lung injury (ALI) rats. METHODS: 40 male Wistar rats were divided into 5 groups: normal control, model control, dectancyl group, water soluble derivative of propolis (WSP) group and ethanol extracted propolis (EEP) group. ALI animal model was performed by oleic acid and LPS twice attack. The pathologic slice was observed with light microscope and the NF-κB p65 activity and CD54 expression were tested by immunohistochemistry (SABC and SP). RESULTS: Both EEP and WSP antagonized the lung edema, decreased the inflammation and inhibited the expression of CD54 and activation of NF-κB p65. CONCLUSION: The increase in the expression of CD54 and the activation of NF-κB p65 in the lung tissues of ALI were involved in the formation of ALI. Propolis ameliorated the lung damage, which maybe related to the inhibition of CD54 expression and NF-κB p65 activation. 相似文献
99.
AIM: To investigate the effects of NF-κB decoy oligodeoxynucleotides (ODNs) on apoptosis in lung cancer cell A549. METHODS: The treatments of lung cancer cells (A549) were divided into three groups: group A (control group); group B (decoy ODN group) and group C (scramble decoy ODN group). FITC-labeled NF-κB decoy ODNs was transfected into A549 with LipofectAMINETM2000. The activation was observed by electrophoretic mobility shift assays (EMSA). The proliferation was observed by growth curve. The apoptosis of cells were observed by flow cytometry and TdT mediated dUTP-biotin Nick End Labeling (TUNEL). The expression of Bcl-2 and Fas were observed by Western blot. RESULTS: After FITC-labeled decoy ODNs was transfected for 1 hour, the decoy ODNs was detected in the nuclei of A549 cells. EMSA performed the depression of the NF-κB binding to the nucleus. The growth curve showed the inhibition of the A549 cell growth and the percentage of apoptosis was increased compare with control group by flow cytometry and TUNEL. The amount of apoptosis inhibitor (Bcl-2) in group A and group C were 2.0 times and 2.1 times more than that in group B, respectively. The level of apoptosis accelerator (Fas) in group B were 2.6 times and 2.3 times more than that in group A and group C, respectively via Western blot. CONCLUSION: The NF-κB decoy ODNs accelerate the apoptosis of lung cancer cell A549 and the mechanism may be due to its inhibiting the expression of Bcl-2 and increasing the level of Fas. 相似文献
100.
D.J. Robinson M.F.B. Dale D. Todd 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(9):921-928
Infection of potato plants with Tobacco rattle virus by its nematode vector can have different outcomes, including the development of spraing symptoms in progeny tubers. A novel syndrome described here comprises a generalized mottle in leaves on all stems, together with virtually total failure to produce daughter tubers. The outcome of infection depends partly on the potato genotype, but field trials with 15 varieties showed that the incidence and severity of spraing symptoms at three sites differed. There was no evidence that this was due to differences in virulence among the virus isolates at the sites, but it was probably the result of environmental differences that influenced the numbers and activity of the vector nematodes. At the most severely affected site, spraing symptoms were found in all varieties tested, except Record, including several that were not affected at the other two sites. Taking both severity and incidence of symptoms into account, the ranking of varieties was similar at each site. The incidence of spraing symptoms was greater in larger than in smaller tubers, and increased with later harvest dates, but did not increase when early harvested tubers were stored. Tobacco rattle viruswas detected in the roots of many of the weeds growing at one of the sites and in the roots of a few plants of the subsequent barley crop. 相似文献