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Characterization of an spm-controlled bronze-mutable allele in maize
1Department of Genetics, University of Wisconsin, Madison, Wisconsin 53706.
Genetics
|April 1, 1984
Summary
The Spm system in maize (Zea mays L.) creates a mutable allele (bz-m13) that affects seed color. This allele exhibits variegation and high mutation rates when the Spm receptor is present.
Area of Science:
- Genetics
- Plant Biology
- Molecular Biology
Background:
- The Spm system in maize (Zea mays L.) regulates gene expression.
- A mutable allele, bz-m13, is formed by the association of the Spm receptor (Rs) with the Bz-1 allele.
Purpose of the Study:
- To investigate the effects of the Spm system on the bz-m13 mutable allele in maize.
- To characterize the phenotypic changes and mutation rates associated with bz-m13 under Spm control.
Main Methods:
- Analysis of anthocyanin production in maize aleurone layers.
- Observation of seed phenotypes under different Spm conditions.
- Quantification of gametic mutation rates to stable bz' and Bz' derivatives.
Main Results:
- In the absence of Spm, bz-m13 conditions full anthocyanin production.
- In the presence of Spm, bz-m13 results in a variegated seed phenotype and high gametic mutation rates (50-83%).
- Bz' derivatives restore anthocyanin production, but not the full enzyme (UFGT) level of the progenitor Bz-1 allele.
Conclusions:
- The Spm system significantly influences the mutable allele bz-m13, inducing variegation and instability.
- The study elucidates the complex regulatory interactions within the Spm system and its impact on maize seed coloration and gene stability.
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