Summary
Sixty two ascospore colour mutants have been induced in Ascobolus immersus: 25 by an acridine (ICR170), 18 by N-methyl-N′-nitro-N-nitrosoguanidine (NG) and 19 by ethyl methanesulfonate (EMS). All these mutants have been crossed to the wild type strain and their conversion spectrum has been determined. It appears that the conversion spectrum is closely related to the origin of the mutants studied with respect to the mutagen by which they were induced. All NG mutants gave numerous asci with postmeiotic segregation and an excess of conversion to wild type over conversion to the mutant type. ICR mutants gave no postmeiotic segregation and an excess of conversion to the mutant type. The majority of EMS mutants behave like NG mutants, but some showed only meiotic segregation with either an excess of conversion to the mutant type or an excess of conversion to wild type. These data are in good agreement with the hypothesis that the nature of the mutation has a strong influence on the conversion spectrum.
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Communicated by W. Gajewski
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Leblon, G. Mechanism of gene conversion in Ascobolus immersus . Molec. Gen. Genet. 115, 36–48 (1972). https://doi.org/10.1007/BF00272216
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DOI: https://doi.org/10.1007/BF00272216