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Oshima K Shiomi T Kuboyama T Sawayanagi T Nishigawa H Kakizawa S Miyata S Ugaki M Namba S 《Phytopathology》2001,91(11):1024-1029
ABSTRACT Two lines of onion yellows phytoplasma producing milder symptoms were isolated from the original line (OY-W). One has an additional characteristic, non-insect-transmissibility (OY-NIM), compared with the other (OY-M). OY-M was established after maintaining OY-W for 11 years on a plant host (Chrysanthemum coronarium) with an insect vector (Macrosteles striifrons), and OY-NIM was isolated after subsequent maintenance of OY-M in plants by periodic grafting. Polymerase chain analysis suggested that OY-NIM cannot traverse the gut or survive in the hemolymph of the leafhopper. OY-W results in witches'-broom formation and stunted growth in the host plant. In contrast, OY-M and OY-NIM do not cause stunting in the host plant, although they result in witches'-broom. Histopathological analysis of these lines revealed that the hyperplastic phloem tissue and severe phloem necrosis seen in OY-W did not exist in OY-M and OY-NIM. This was attributed to a reduction in the population of phytoplasma in tissues in both OY-M- and OY-NIM-infected plants. The results suggest that the cause of stunting and phloem hyperplasia may be genetically different from the cause of witches'-broom. Pulsed field gel electrophoresis analysis showed that OY-M had a smaller genome size ( approximately 870 kbp) than OY-W ( approximately 1,000 kbp). Thus, some of the OY-W genes responsible for pathogenicity may not be present in OY-M. 相似文献
2.
The metabolism of fenitrothion was investigated in highly resistant (Akita-f) and susceptible (SRS) strains of the house fly, Musca domestica L. The Akita-f strain was 3500 times more resistant to fenitrothion than the SRS strain. Fenitrothion, topically applied to the flies, was metabolized in vivo far faster in the Akita-f strain than in the SRS strain. In vitro studies revealed that fenitrothion was metabolized by a cytochrome P-450-dependent monooxygenase system and glutathione S-transferases. The former oxidase system metabolized fenitrothion in vitro into fenitrooxon and 3-methyl-4-nitrophenol as major metabolites, and into 3-hydroxymethyl-fenitrothion and 3-hydroxymethyl-fenitrooxon as minor metabolites. Glutathione S-transferases metabolized fenitrothion into desmethylfenitrothion. The cytochrome P-450-dependent monooxygenase system and glutathione S-transferases of the resistant Akita-f strain had 1.4 to 2.2 times and 9.7 times, respectively, as great activities as those of the susceptible SRS strain. These results suggest the importance of glutathione S-transferases in fenitrothion resistance in the Akita-f strain. 相似文献
3.
In planta dynamic analysis of onion yellows phytoplasma using localized inoculation by insect transmission 总被引:1,自引:0,他引:1
Wei W Kakizawa S Suzuki S Jung HY Nishigawa H Miyata S Oshima K Ugaki M Hibi T Namba S 《Phytopathology》2004,94(3):244-250
ABSTRACT Due to the lack of a means to inoculate plants mechanically, the histological dynamics and in planta spread of phytoplasmas have been studied very little. We analyzed the dynamics of plant infection by phytoplasmas, using a technique to infect a limited area of a leaf, nested polymerase chain reaction (PCR), real-time PCR, and immunohistochemical visualization. Following localized inoculation of a leaf of garland chrysanthemum (Chrysanthemum coronarium) by the vector leafhopper Macrosteles striifrons, the onion yellows (OY) phytoplasma spread within the plant from the inoculated leaf to the main stem (1 day postinoculation [dpi]), to the roots and the top leaf (2 dpi), and to other leaves from top to bottom (from 7 to 21 dpi). The populations of the OY phytoplasmas in inoculated leaves and roots increased approximately sixfold each week from 14 to 28 dpi. At 14 dpi, the OY phytoplasmas colonized limited regions of the phloem tissue in both the root and stem and then spread throughout the phloem by 21 dpi. This information should form the basis for elucidating the mechanisms of phytoplasma multiplication and migration within a plant host. 相似文献
4.
Watanabe Kikyo Sakane Aya Terada Ryosuke Nishigawa Hisashi Suzuki Masashi Ugaki Masashi 《Journal of General Plant Pathology》2021,87(6):366-376
Journal of General Plant Pathology - Virus-induced gene silencing (VIGS) is a rapid and efficient tool to elucidate plant gene functions by inserting a target gene fragment into a viral genome and... 相似文献
5.
Miwa Uchibori Aiko Hirata Masashi Suzuki Masashi Ugaki 《Journal of General Plant Pathology》2013,79(2):115-122
Begomoviruses are transmitted by a single species of vector insect, the whitefly Bemisia tabaci, in a circulative manner. However, the mechanisms of this strict vector specificity have not been clarified. By immunoelectron microscopy, we showed that a begomovirus, Tomato yellow leaf curl virus (TYLCV), can enter midgut epithelial cells of the vector whitefly B. tabaci but not those of a nonvector whitefly, Trialeurodes vaporariorum, belonging to the same family. In midgut epithelial cells of viruliferous B. tabaci, the virus was localized in vesicle-like structures, suggesting endocytosis as an entry mechanism. These structures were also observed in midgut cells of nonviruliferous B. tabaci that had fed on healthy plants and in those of the nonvector T. vaporariorum that had fed on virus-infected plants. Vesicles containing TYLCV particles were observed most frequently in cells in the anterior part of the descending midgut, suggesting that this is the major entry site. These results clearly demonstrated that the virus-containing vector and nonvector whiteflies differ in the cellular localization of the virus and strongly suggest that a critical step in determining the vector insect specificity of begomoviruses is the entry of the viruses into midgut epithelial cells. 相似文献
6.
Fuji Shin-ichi Mochizuki Tomofumi Okuda Mitsuru Tsuda Shinya Kagiwada Satoshi Sekine Ken-Taro Ugaki Masashi Natsuaki Keiko T. Isogai Masamichi Maoka Tetsuo Takeshita Minoru Yoshikawa Nobuyuki Mise Kazuyuki Sasaya Takahide Kondo Hideki Kubota Kenji Yamaji Yasuyuki Iwanami Toru Ohshima Kazusato Kobayashi Kappei Hataya Tatsuji Sano Teruo Suzuki Nobuhiro 《Journal of General Plant Pathology》2022,88(2):105-127
Journal of General Plant Pathology - An increasing number of plant viruses and viroids have been reported from all over the world due largely to metavirogenomics approaches with technological... 相似文献
7.
Wei W Kakizawa S Jung HY Suzuki S Tanaka M Nishigawa H Miyata S Oshima K Ugaki M Hibi T Namba S 《Phytopathology》2004,94(7):683-686
ABSTRACT Antisera raised against phloem-limited phytoplasmas generally react only with the phytoplasma strain used to produce the antigen. There is a need for an antiserum that reacts with a variety of phytoplasmas. Here, we show that an antiserum raised against the SecA membrane protein of onion yellows phytoplasma, which belongs to the aster yellows 16S-group, detected eight phytoplasma strains from four distinct 16S-groups (aster yellows, western X, rice yellow dwarf, and elm yellows). In immunoblots, approximately 96-kDa SecA protein was detected in plants infected with each of the eight phytoplasmas. Immunohistochemical staining of thin sections prepared from infected plants was localized in phloem tissues. This antiserum should be useful in the detection and histopathological analysis of a wide range of phytoplasmas. 相似文献
8.
Akira Shinjo Yuko Araki Ko Hirano Tsutomu Arie Masashi Ugaki Tohru Teraoka 《Journal of General Plant Pathology》2011,77(2):85-92
Mannose-binding rice lectin (MRL), which is almost identical to the salt-induced protein SalT, binds to mannose and glucose
residues. Expression of the MRL gene in response to infection with Magnaporthe oryzae, the rice blast fungus, was stronger in the incompatible interaction than in the compatible. Transgenic rice plants that
constitutively over-expressed MRL strongly suppressed the growth of invasive hyphae of the fungus on leaf sheaths and the
development of typical susceptible-type lesions on leaf blades, but did not affect penetration by the fungus in comparison
with the wild-type. On a polycarbonate plate, purified recombinant MRL inhibited conidial attachment and appressorium formation
but not conidial germination. These results suggest that MRL may play an essential role in disease resistance by suppressing
development of M. oryzae in situ. 相似文献
9.
Hisashi Nishigawa Kenro Oshima Shin-ichi Miyata Masashi Ugaki Shigetou Namba 《Journal of General Plant Pathology》2003,69(3):194-198
Two lines of onion yellows phytoplasma with reduced pathogenicity have been isolated from the original wild-type line (OY-W).
One is a line with mild symptoms (OY-M) and the other is a non-insect-transmissible line, also with mild symptoms (OY-NIM).
We previously reported heterogeneity in extrachromosomal DNA (EC-DNA) species in these lines. In this report, another EC-DNA,
EcOYNIM, from OY-NIM was cloned and sequenced, providing a complete set of EC-DNAs from the three OY lines. To monitor each
phytoplasma in synergism or cross-protection experiments, a pair of polymerase chain reaction (PCR) primers that universally
amplify a portion of the EC-DNAs that are characteristic of each line was designed. Using this primer set, a line-specific
fragment was amplified from the total DNA of each plant inoculated with one or more phytoplasma lines. The PCR product sizes
differ for each phytoplasma line, so the lines can be distinguished even in plants infected with multiple lines. Because EC-DNAs
are more abundant than chromosomal genes in phytoplasma cells, this primer set will be valuable for detecting and discriminating
these phytoplasma lines and for analyzing their interaction.
Received: October 21, 2002 / Accepted: January 8, 2003
RID="*"
ID="*" The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession number AB097150
Acknowledgments This work was supported partly by Grants-in-Aid of Scientific Research from the Japan Society for the Promotion of Science
(JSPS) (09460155 and 13306004), a Grant-in-Aid of Scientific Research on Priority Areas (C) “Genome Biology” from the Ministry
of Education, Culture, Sports, Science, and Technology of Japan, and the Program for the Promotion of Basic Research Activities
for Innovative Biosciences (PROBRAIN) of the Bio-oriented Technology Research Advancement Institution. 相似文献
10.
Hui Chen Atsushi Tamai Masashi Mori Masashi Ugaki Yoshikazu Tanaka Partha P. Samadder Akio Miyao Hirohiko Hirochika Naoto Yamaoka Masamichi Nishiguchi 《Journal of General Plant Pathology》2010,76(2):152-160
RNA-dependent RNA polymerases (RDRs) play a key role in various RNA silencing pathways in many organisms. Using the nucleotide
sequence of SGS2/SDE1/RDR6 in Arabidopsis as the search query for sequences that flank the insertions of rice retrotransposon Tos17, we selected rice mutant lines (OsRDR1). RT-PCR analysis showed that OsRDR1 mRNA was undetectable in leaves and calli of the mutants, while it was detected in wild type. RNA silencing was induced by
particle bombardment to investigate any effects of OsRDR1 on RNA silencing with β-glucuronidase or green fluorescent protein DNA/RNA in the mutant lines. The results showed that RNA
silencing was impaired in these mutant lines by inverted repeat (IR) DNA or in vitro transcribed double-stranded RNA. Further,
the mutant lines were bombarded with Brome mosaic bromovirus (BMV, a ssRNA virus) or Wheat dwarf
geminivirus (WDV, a ssDNA virus), each carrying the IR sequence of a reporter gene. As a result, RNA silencing was impaired by BMV. Interestingly,
however, it was not impaired by WDV. Thus we propose that OsRDR1 is required for RNA silencing mediated by Bromovirus, but not by Geminivirus in this system. 相似文献
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