Fig. 5. AP3 and PI expression in wild-type and mutant flowers. Sections of inflorescences in A-H were hybridized with an AP3 probe and in I-P were hybridized with a PI probe. All photographs are at the same magnification. The numbers indicate the bud stage; im, inflorescence meristem. (A) Wild-type showing AP3 RNA expression in the floral meristem at a high level at stages 3 and 4 and in whorl two and three in an old flower. (B) ask1-1 exhibiting AP3 RNA expression at the same position and nearly the same level as in the wild-type flower. (C,D) lfy-5 has a similar expression pattern of AP3 RNA to that in the wild type, but the expression level is slightly reduced. (E,F) lfy-6 showing no or very low AP3 RNA expression (arrows) in a young and an old bud, respectively. (G,H) lfy-5 ask1-1 double mutant showing that AP3 RNA expression is much reduced and largely undetectable. Only very low AP3 RNA expression in limited areas was observed in some buds (arrows). (I) Wild-type showing that PI RNA is present at a high level in a stage-3 floral meristem and in whorl two and three of old flowers. (J) ask1-1; the PI RNA signal shows a similar pattern to that in the wild-type flower. (K,L) lfy-5; the PI RNA expression pattern is similar to that in the wild type, but the level of expression is slightly lower than the normal. (M,N) lfy-6 showing very limited PI RNA expression in a floral bud (arrow). (O,P) lfy-5 ask1-1 ; PI RNA expression is also much reduced. Only an occasional small region of PI expression could be observed in some buds (arrows).