Figure 4.

Expression of mNtGAMYB2 in tobacco results in severe phenotypic defects. A, Schematic representation of the 35S-GAMYB2 and 35S-mGAMYB2 transgenes. B, mGAMYB2 tobacco plants displayed either no (N) or strong (S) phenotypic defects. C, Two independent mGAMYB2-S lines (S1 and S3), with only the S3 line exhibiting flowers and seed setting. D, Detail of a leaf exhibiting chlorosis. E, Detail of mGAMYB2-S flowers that are white and display strong developmental defects. For D and E, the various organs were digitally extracted for comparison. F, Defects displayed by a 12-month old mGAMYB2-S plant. G, RT-qPCR measurement of GAMYB2 transcript levels in two independent mGAMYB2-N lines (N1 and N2) and three independent mGAMYB2-S lines (S1–S3). RNA was extracted from two young leaves of 12-week-old plants and GAMYB2 mRNA levels were normalized to PROTEIN PHOSPHATASE2A. Measurements are the average of three technical replicates.