151. Validation of Aintegumenta as a gene to modify floral size in ornamental plants.
- Author
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Manchado‐Rojo, María, Weiss, Julia, and Egea‐Cortines, Marcos
- Subjects
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GENETIC transcription in plants , *PLANT growth , *PLANT cellular signal transduction , *GENE expression in plants , *SNAPDRAGONS , *PHENOTYPES ,FLOWER size - Abstract
The gene AINTEGUMENTA ( At ANT) is an APETALA2 transcription factor in Arabidopsis activating growth downstream of auxin signalling. Lateral organ size is positively correlated with ANT expression in Arabidopsis. We tested the use of At ANT as a tool to modify floral size in two different plants used as model organisms and ornamental crops, Petunia × hybrida and Antirrhinum majus. Petunia plants expressing Ph ANT RNAi showed a decrease in Ph ANT expression correlated with smaller petal limbs. In contrast Petunia plants overexpressing At ANT had larger petal limbs. Petal tube length was less affected in down-regulation of Ph ANT or overexpression of At ANT. Overexpression of At ANT in Antirrhinum caused increased flower size via increased petal limb width and tube length. Down-regulation of Ph ANT showed an effect on cell size while overexpression of At ANT in Petunia and Antirrhinum caused significant increases in cell expansion that could explain the differences in floral organ size. The endogenous expression levels of Ph ANT and Am ANT tended to be higher in the limb than in the tube in both Antirrhinum and Petunia. At ANT overexpression caused significant Am ANT up-regulation in Antirrhinum limbs but not of Ph ANT in Petunia, indicating differences in the regulatory network. The differential effect of At ANT on limb and tube in Petunia and Antirrhinum correspond to phenotypic differences observed in natural variation in the corresponding genus indicating a relation between the phenotypic space of a genus and the effect of modified ANT levels, validating ANT as a gene to modify floral size. [ABSTRACT FROM AUTHOR] more...
- Published
- 2014
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