Abstract
Strains of the Japanese pear pathotype of Alternaria alternata were screened for double-stranded RNAs (dsRNAs). Four strains had several dsRNAs; strain N18 was associated with several dsRNAs and had impaired growth phenotypes such as irregular mycelium and abnormal pigmentation. We isolated dsRNA-cured isolates from strain N18 by single-conidium isolation. The dsRNA-cured isolates had recovered normal growth and pigmentation. Enlarged vesicles were observed in mycelial cells of the original dsRNA-carrying N18 strain. DAPI nuclear staining revealed regression of the nuclei in dsRNA-carrying N18 cells. These results indicate that the dsRNAs might have negative effects, such as apoptosis-like cell death, on the host fungus.
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Acknowledgments
We thank Prof. T. Tsuge (Nagoya University), Dr. F. Yasuda (Tottori Prefectural Agriculture and Forest Research Institute), Prof. D. G. Gilchrist (University of California), Prof. J. Hille (University of Groningen), Mr. H. Shiomi (Takii and Co. Ltd.), and Prof. H. Otani (Tottori University) for providing the Alternaria strains. We also thank Prof. T. Arie (Tokyo University of Agriculture & Technology) and Prof. T. Teraoka for their valuable advice. This research was supported in part by Grants-in-Aid for Scientific Research (No. 20580045) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan and from the Industrial Technology Development Organization (No. 08C46503c).
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Fuke, K., Takeshita, K., Aoki, N. et al. The presence of double-stranded RNAs in Alternaria alternata Japanese pear pathotype is associated with morphological changes. J Gen Plant Pathol 77, 248–252 (2011). https://doi.org/10.1007/s10327-011-0315-0
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DOI: https://doi.org/10.1007/s10327-011-0315-0