Figure 4.

The CER6 promoter directs epidermis-specific expression of GUS in Arabidopsis throughout the shoot from very early stages of development, as well as in tobacco. Seedlings (A and B) and tissue sections (D and E) of Arabidopsis and tobacco (F) plants transformed with the CER6 promoter-GUS construct, and incubated in 5-bromo-4-chloro-3-indolyl-β-d-glucuronide assay buffer. GUS activity is indicated by a blue precipitate. A, One-day-old seedlings; B, 8-d-old seedlings; C, free-hand cross section of the top of a bolting stem; D, silique cross section; E, leaf cross section; F, tobacco stem cross section.