Fig. 3. lbl1 suppresses the epidermal patterning defects in Rld1-O. Scanning electron micrographs of the adaxial (A1-E1) and abaxial (A2-E2) epidermal surfaces of adjacent mature adult leaves samples. (A3-E3) High magnification of selected images to illustrate specific epidermal patterning defects. Compared with wild-type leaves (A), Rld1-O leaves (B) display normal polarity near the margins, but, in the center of the lamina, bulliform cells and macrohairs develop on the abaxial surface. Note the presence of isolated macrohairs (arrow in B3) and the overlap between macrohairs on the adaxial and abaxial epidermis. The regular spacing between bulliform cell files and between macrohairs is disrupted in weakly phenotypic lbl1-ref leaves (C), and bulliform cell files are frequently disrupted (arrow in C3). lbl1-ref Rld1-O leaves with a mild rolled phenotype (D) develop bulliform cells on both the adaxial and abaxial epidermis, and macrohairs on the abaxial epidermis in some regions of the blade. As in lbl1-ref, bulliform cell files are discontinuous and irregularly spaced (arrow in D3). Epidermal patterning in lbl1-ref Rld1-O leaves with a flattened morphology (E) is indistinguishable from that of wild type. ad, adaxial; ab, abaxial; mh, macrohair; bc, bulliform cell. All samples are oriented with the margin towards the right. Scale bars: in A1-E2, 1 mm; in A3-E3, 0.25 mm.