Figure 2.

Altered phenotypes of SlARF4 down-regulated plants. A, SlARF4 protein represses in vivo the activity of the synthetic promoter DR5. Tobacco protoplasts were transformed either with the reporter construct (DR5::GFP) alone or with both the reporter and effector constructs (35S-SlARF4) and incubated in the presence or absence of 50 μm 2,4-D. GFP fluorescence was measured 16 h after transfection. A mock effector construct lacking SlARF4 was used as a control for the cotransfection experiments. Transformations were performed in triplicate. Mean fluorescence is indicated in arbitrary units ± se. B, Expression of SlARF4 in transgenic lines analyzed by semiquantitative real-time PCR analysis in leaves. In each PCR reaction, the internal reference ubiquitin (Ubi) gene was coamplified with the SlARF4 gene. C, Wild-type and SlARF4 antisense plants at the same stage of development (6-week-old plants). D, Dark-green and heart-shaped phenotype of SlARF4 down-regulated fruit at 35 DPA compared with wild-type fruit at the same stage. E, Upward-curled leaf phenotype of SlARF4 down-regulated fruit. The leaves of SlARF4 down-regulated lines exhibit severe in-rolling along the longitudinal axis of the leaf compared with wild-type plants grown in the same conditions at the same stage. WT, Wild type. [See online article for color version of this figure.]