Fig. 8. Analysis of class I knox gene expression in the bop1-1 mutant. (A) Analysis by RT-PCR of transcripts of the KNAT1, KNAT2 and KNAT6 genes. Cot, cotyledon (including ectopic outgrowths in the case of the bop1-1 mutant); Rosette, rosette leaves (including ectopic outgrowths in the case of the bop1-1 mutant); SAM, shoot apical meristem region. L, Ler; b, bop1-1. The ß-tubulin (TUB4) gene was amplified as a positive control. (B) A 23-day-old wild-type seedling. (C) A detached cotyledon from wild-type plant. (D) A detached leaf from wild-type plant. Arrows in C and D represent the weak GUS-expressing region at the petiole base. (E) A 23-day-old bop1-1 mutant seedling. Note the strong expression of GUS on the hypocotyls and the abaxial side of leaf petioles. (F) A detached cotyledon from bop1-1 plant. (G) A detached leaf from bop1-1 plant. Note the strong expression of GUS on the basal region of petioles (F,G, arrows). (C,D,F,G) Adaxial side views. r, rosette leaves; c, cotyledons; h, hypocotyls.