Histochemical localization of GUS expression under control of the Atndt1 and Atndt2 promoter in A. thaliana. Plants were grown as described under “Experimental Procedures.” A, shown is Atndt1-promoter-GUS activity in a 10-day-old seedling. B, shown is Atndt1-promoter-GUS activity in a juvenile leaf from a 7-week-old plant. C, shown is Atndt1-promoter-GUS activity in developing siliques. D, shown is Atndt1-promoter-GUS activity in flowers. E and F, shown are Atndt1-promoter-GUS activity in root tips and root branches. G, shown is Atndt2-promoter-GUS activity in 2-week-old seedlings. H, shown is Atndt2-promoter-GUS activity in a mature leaf. I, shown is Atndt2-promoter-GUS activity in developing siliques. J, shown is Atndt2-promoter-GUS activity in flowers. K, shown is Atndt2-promoter-GUS activity in anthers. L, shown is Atndt2-promoter-GUS activity in roots.