Abstract
Neurospora tetrasperma is a pseudohomothallic fungus closely related to the better-studied, but heterothallic fungal model system, N. crassa. Pseudohomothallism offers powerful approaches for doing genetic analysis of sexual phase-specific processes such as repeat-induced point mutation (RIP), meiotic silencing, and ascospore development. However, N. tetrasperma is naturally resistant to hygromycin, which precluded the application to N. tetrasperma of N. crassa transformation protocols that involved the electroporation of conidia with transforming DNA, including the hph gene, followed by selection of hygromycin-resistant transformants on hygromycin medium. This limitation was circumvented by our discovery that erg-3 mutations render N. tetrasperma hygromycin-sensitive. Transformation of N. tetrasperma erg-3 mutants enabled us to screen for recessive RIP-deficient mutants; demonstrate meiotic silencing by unpaired DNA; and construct novel mutant strains. We can now make N. tetrasperma strains in which transforming DNA integrates only by homologous recombination and use them to create knock-out mutants, possibly with DNA amplicons developed for making knock-outs in N. crassa.
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Acknowledgement
I thank Kevin McCluskey for many useful suggestions. My research in CDFD is supported by the Haldane Chair.
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Kasbekar, D.P. (2015). What Have We Learned by Doing Transformations in Neurospora tetrasperma?. In: van den Berg, M., Maruthachalam, K. (eds) Genetic Transformation Systems in Fungi, Volume 2. Fungal Biology. Springer, Cham. https://doi.org/10.1007/978-3-319-10503-1_3
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DOI: https://doi.org/10.1007/978-3-319-10503-1_3
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