期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1987
卷号：84
期号：12
页码：4293-4297
DOI：10.1073/pnas.84.12.4293
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：We demonstrate here that yeast killer viruses, previously thought to be transmitted only by cytoplasmic mixing during division, mating, or other induced forms of cell fusion, are capable of extracellular transmission. Viral particles from standard K1 and K2 killer strains were used to inoculate sensitive cells of Saccharomyces cerevisiae, rendered competent by spheroplasting, lithium acetate treatment, or by natural mating. Extracellular transmission of the killer viruses was judged by the following criteria and controls. Filter-sterilized virus inocula were shown to be free of viable yeast cells, and host cells treated in the absence of added virus did not yield killer progeny. Infected clones originating from spheroplasts or lithium acetate-treated cells were shown to possess the genotype of the host strain and the killer phenotype of the infecting virus. Infected clones derived from complementary mating pairs were found to be wild-type diploids, whose meiotic segregants exhibited 2:2 segregation for unlinked nutritional markers and 4:0 segregation for the killer phenotype. This technique is generally applicable to the study of interactions between yeast viruses and different hosts and suggests that extracellular transmission may be a natural route for the inheritance and dissemination of mycoviruses.
