Figure 5

GUS-staining assays of four PtWOX promoters. (A–B) GUS expression in (A) 2-week-old sapling and (B) root of P _PtoWOX5a ::GUS-expressing poplar plants. The insert in A shows GUS expression in the leaf, and that the GUS expression in B is mainly focused on a small area immediately behind the root cap in AR tips. (C–D) GUS expression in (C) 2-week-old sapling and (D) root tip of P _PtoWOX11/12a ::GUS-expressing poplar plants. GUS is expressed in a small area immediately behind the root cap in AR tips, and the insert in C shows no GUS expression in leaf. (E–G) GUS expression in (E) 2-week-old sapling, (F) root including a small area behind the root cap indicated by an arrow, and (G) the CAM zone of P _PtoWUSa ::GUS-expressing poplar plants. The insert in E shows GUS expression in the SAM area in a halved shoot apical part. (H–J) GUS expression in (H) 2-week-old sapling, (I) root tip and (J) stem of P _PtoWOX4a ::GUS-expressing poplar plants. The insert in H shows no GUS expression in the SAM area in a halved shoot apical part. The bar represents 1 cm in A, C, E, and H; 1 mm in D; 0.5 mm in B, F, and I; and 0.1 mm in G, J, and the inset of E.