Mycoviruses with double-stranded RNA (dsRNA) genomes are frequently encountered in Aspergillus isolates. A detailed study of such dsRNA elements in black Aspergillus isolates collected worldwide was carried out, and the data were analysed. The results indicate that about 10% of black Aspergilli are infected. However, the geographic distribution of infected isolates exhibits large variations; 3–13% of the isolates collected from different continents were found to carry dsRNA elements. Hybridization experiments indicated that electrophoretic banding patterns are not reliable tools for estimating the diversity of these mycovirus genomes. Among strains representing other Aspergillus sections, dsRNA segments indicative of mycovirus infection were observed for the first time in 4 species (A. leporis, A. petrakii, A. fumigatus and A. primulinus). The latter species is able to reproduce sexually. This is the second report on the detection of naturally-occurring dsRNAs in sexually reproducing Aspergillus species. The presence of viruslike particles in these and other Aspergilli was also examined by electron microscopy. Most infected Aspergillus isolates examined were found to carry virus-like particles in the size range 36–40 nm.
Adler-Moore, J. (1985) Subcellular particles in pathogenic fungi. In: Howard, D. H. (ed.) Fungi Pathogenic for Humans and Animals, Part B, Pathogenicity and Detection II Marcel Dekker, New York, pp. 103–121.
Buck, K. W. (1986) Fungal virology - an overview. In: Buck, K. W. (ed.) Fungal virology. CRC Press, Boca Raton, Florida, pp. 1–84.
Buck, K. W. (1998) Molecular variability of viruses of fungi. In: Bridge, P., Couteaudier, Y., Clarkson, J. (eds) Molecular variability of fungal pathogens. CAB International, London, pp. 53–72.
Buck, K. W., Girvan, R. F., Ratti, G. (1973) Two serologically distinct double-stranded ribonucleic acid viruses isolated from Aspergillus niger Biochem. Soc. Trans. 1, 1138–1140.
Buck, K. W., Ratti, G. (1975) Biophysical and biochemical properties of two viruses isolated from Aspergillus foetidus. J. Gen. Virol. 27, 211–224.
Buck, K. W., Ratti, G. (1977) Molecular weight of double-stranded RNA: a re-examination of Aspergillus foetidus virus S RNA components. J. Gen. Virol. 37, 215–219.
Charter, N. W., Buck, K. W., Brasier, C. M. (1993) De novo generation of mitochondrial DNAplas-mids following cytoplasmic transmission of a degenerative disease in Ophiostoma novo-ulmi. Curr. Genet. 24, 505–514.
Coenen, A., Kevei, F, Hoekstra, R. (1997) Factors affecting the spread of double-stranded RNA viruses in Aspergillus nidulans. Genet. Res. Camb. 69, 1–10.
Compel, P., Papp, I., Bibó, M., Fekete, C., Hornok, L. (1998) Genetic relationships and genome organization of double-stranded RNA elements of Fusarium poae. Virus Genes 18, 49–56.
Diepeningen, van, A. D. (1999) Horizontal transfer of genetic elements in the black Aspergilli. Ph. D. Thesis, Wagenigen Agricultural University, Wageningen, The Netherlands.
Diepeningen, van, A. D., Debets, A. J. M., Hoekstra, R. F. (1997) Heterokaryon incompatibility blocks virus transfer among natural isolates of black Aspergilli. Curr. Genet. 32, 209–217.
Elias, K. S., Cotty, P. J. (1996) Incidence and stability of infection by double-stranded RNA genetic elements in Aspergillus section Flavi and effects on aflatoxigenicity. Can. J. Bot. 74, 716–715.
Fekete, C., Giczey, G., Papp, I., Szabó, L., Hornok, L. (1995) High-frequency occurrence of viruslike particles with double-stranded RNA genome in Fusarium poae. FEMS Microbiol. Lett. 131, 295–299.
Gams, W., Christensen, M., Onions, A. H. S., Pitt, J. I., Samson, R. A. (1985) Infrageneric taxa of Aspergillus. In: Samson, R. A., Pitt, J. I. (eds) Advances in Penicillium and Aspergillus systematics. Plenum Press, New York, pp. 55–61.
Hoffmann, T., Golz, C., Schieder, O. (1994) Foreign DNA sequences are received by a wild-type strain of Aspergillus niger after co-culture with transgenic higher plants. Curr. Genet. 27, 70–76.
Hollings, M., Stone, O. M. (1971) Viruses that infect fungi. Ann. Rev. Phytopathol. 9, 93.
Kim, J. W., Bozarth, R. F. (1985) Intergeneric occurrence of related fungal viruses: the Aspergillus ochraceus virus complex and its relationship to the Penicillium stoloniferum virus S. J. Gen. Virol. 66, 1991–2002.
Kozakiewicz, Z. (1989) Aspergillus species on stored products. Mycol. Papers 161, 1–188.
Leach, J., Finkelstein, D. B., Rambosek, J. A. (1986) Rapid miniprep of DNA from filamentous fungi. Fungal Genet. Newslett. 33, 32–33.
Li, J. K., Parker, B., Kowalik, T. (1987) Rapid alkaline blot-transfer of viral dsRNAs. Anal. Biochem. 163, 210–218.
Liang, P., Chen, K. (1987) Virus transmission through interspecies protoplast fusion in Aspergillus. Trans. Br. Mycol. Soc. 89, 73–81.
Marienfeld, J. R., Unseld, M., Brandt, P., Brennicke, A. (1997) Viral nucleic acid sequence transfer between fungi and plants. Trends in Genetics 13, 260–261.
Morris, T. J., Dodds, J. A. (1979) Isolation and analysis of double-stranded RNA from virus-infected plant and fungal tissue. Phytopathology 69, 854–858.
Pontecorvo, G., Roper, J. A., Hemmons, L. M., MacDonald, K. D., Bufton, A. W. J. (1953) The genetics of Aspergillus nidulans. Adv. Genet. 5, 141–238.
Raper, K. B., Fennell, D. I. (1965) The genus Aspergillus. Williams & Wilkins, Baltimore, Md.
Ratti, G., Buck, K. W. (1972) Virus particles in Aspergillus foetidus: a multicomponent system. J. Gen. Virol. 14, 165–175.
Rogers, H. J., Buck, K. W., Brasier, C. M. (1987) A mitochondrial target for double-stranded RNA in diseased isolates of the fungus that causes Dutch elm disease. Nature 329, 558–560.
Schmidt, F. R., Davis, N. D., Diener, U. L., Lemke, P. A. (1983) Cycloheximide induction of afla-toxin synthesis in a nontoxigenic strain of Aspergillus flavus. Biotechnology 1, 794–795.
Schmidt, F. R., Lemke, P. A., Esser, K. (1986) Viral influences on aflatoxin formation by Aspergillus flavus. Appl. Microbiol. Biotechnol. 24, 248–252.
Sutherland, M. L., Brasier, C. M. (1995) Effect of d-factors on in vitro cerato-ulmin production by the Dutch elm disease pathogen Ophiostoma novo-ulmi. Mycol. Res. 99, 1211–1217.
Udagawa, S.-I., Toyazaki, N., Tsubouchi, H. (1993) Neosartorya primulina, a new species of food-borne Ascomycetes. Mycotaxon 47, 359–366.
Varga, J., Kevei, F., Vágvölgyi, C., Vriesema, A., Croft, J. H. (1994) Double-stranded RNA myco-viruses in section Nigri of the Aspergillus genus. Can. J. Microbiol. 40, 325–329.
Varga, J., Rinyu, E., Kevei, É., Tóth, B., Kozakiewicz, Z. (1998) Double-stranded RNA mycovirus-es in species of Aspergillus sections Circumdati and Fumigati. Can. J. Microbiol. 44, 569–574.
Wickner, R. B. (1996) Double-stranded RNA viruses of Saccharomyces cerevisiae. Microbiol. Rev. 60, 250–265.
Dedicated to Professor Lajos Ferenczy on the occasion of his 70th birthday.
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Varga, J., Tóth, B., Szencz, S. et al. Double-Stranded RNA Elements and Virus-Like Particles in Aspergilli. BIOLOGIA FUTURA 52, 355–363 (2001). https://doi.org/10.1556/ABiol.52.2001.2-3.20
- double-stranded RNA
- virus-like particle