Summary
Multiple genetic and epigenetic changes were detected within one plant generation at the bz2:: mu1 mutable allele in a population of 118 plants. Loss of somatic instability in bz2::mu1 was usually correlated with methylation of the Mu1 transposable element; in 6 plants, somatic instability was lost as a result of mutations in bz2::mu1. This is a surprisingly high frequency of mutation per allele (2.5%) for the Mutator family, for which germinal revertants occur at a frequency of about 10−4 per gamete. One germinal excision event was found that contained an 8 by deletion, frameshift mutation in Bronze-2. The three other mutants described occurred as a result of abortive transposition, in which 75–77 by deletions were generated at the junction between Bronze-2 and Mu1. We discuss the possible mechanisms, and the role of host factors in abortive transposition in maize.
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Levy, A.A., Walbot, V. Molecular analysis of the loss of somatic instability in the bz2::mu1 allele of maize. Molec. Gen. Genet. 229, 147–151 (1991). https://doi.org/10.1007/BF00264223
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DOI: https://doi.org/10.1007/BF00264223