Figure 3.

Transient gene expression in roots of transgenic plants carrying an Msenod12A–uidA fusion after particle bombardment: Optimization bombardments: root bombarded with vector DNA [pDH51 (19)] (a) or with a 35S–uidA construct (20) (b). Blue spots correspond to cells transiently expressing GUS. (c) A cortical cell showing GUS activity with a gold particle (within the ring) in the nucleus. enod40 bombardments: division of cortical cells expressing Msenod12A (blue) in a root bombarded with a 35S–Mtenod40 construct (d). (e) Interference contrast micrograph of a cortical cell division after bombardment as in d. (f and g) Cortical cell division with accumulated amyloplasts (arrows) as seen in 2-μm sections after toluidine blue (f) and Lugol staining (g), respectively. (h) Autofluorescence revealed nuclei (arrows) in dividing cells (8-μm section). (i) Transversal section (8 μm) showing cell divisions (white bracket) outside the endodermis (fluorescent cell walls; en) in front of a xylem pole (x). ph, Phloem tissue. Large and small arrows are as in Fig. 1e. [Bar = 100 μm (a and b), 12 μm (c and i), 25 μm (d–g), and 20 μm (h).]