|Class C floral organ identity genes|
|The Class C Floral Organ Identity genes are necessary for the proper development of the stamens and carpels normally found in the third and fourth whorls of the flower. The Class A and C activities are mutually antagonistic, meaning in Class C mutants, the Class A activity expands to include the two inner whorls.||
|AG is the only known Class C gene and is required for normal stamen and carpel development.|
|In addition, AG is required for determinacy, such that ag mutant flowers are indeterminate and continue to elaborate new whorls of organs, giving rise to the "flower within a flower" phenotype. In agamous mutant flowers, the 3rd whorl stamens are replaced by petals, and the 4th whorl carpels are replaced by a new flower. Thus, the generalized phenotype of ag mutant flowers is (4 sepals, 4 petals, 6 petals)n.||
|Expression of AG RNA in wild-type flowers occurs in the two inner whorls from stage 3 onwards, although the accumulation of AG RNA expands to include all four whorls in apetala2 mutant flowers. AG activity is responsible for preventing the accumulation of AP1 RNA in the two inner whorls. AG is a MADS-box gene and thus likely encodes a DNA-binding transcriptional regulator.|
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