Confocal microscopic analysis of SEP:GFP during petal development. (A) SEP3:GFP signal at the adaxial side of a stage 11 petal. Nuclei with SEP3:GFP proteins are visible as bright green spots against the green autofluorescent background of the petal. (B) Cross section through a petal of approximately stage 10 showing higher SEP3:GFP signal in the adaxial epidermis than the abaxial epidermis. Cell membranes are stained with the red dye FM4-64. (C) SEP3:GFP signal at the abaxial side of a stage 11 petal. The images in (A) and (B) are each composed of two separate, overlapping projections. (ab) abaxial side; (ad) adaxial side; (b) blade of petal; (c) claw of petal. Scale bars of (A) and (C) 50 μm and scale bar of (B) 15 μm.