Fig. 3. Embryo development is abnormal in semaphore mutants. KNOX immunohistolocalizations of 12 DAP embryos. Non-mutant embryos (A,B) are larger than sem1 mutant siblings (C-H) and show no KNOX accumulation in the incipient leaf (arrow in B and D), leaf primordia (numbered), pericarp (p), scutellum (s), coleoptile (c) or endosperm (en). Moderately retarded sem1 mutants (C-D) and more severely retarded mutants (E-H) exhibit ectopic KNOX accumulation in the endosperm and fewer (if any) leaf primordia than non-mutant siblings. The arrows in F and H indicate the shoot meristem. Scale bars: 200 µm, in A for A,C,E,G and in B for B,D,F,H.