Summary of DR5::GUS staining patterns in primary roots of T₁ transgenic plants.

<p>(A) Varied expression patterns of DR5::GUS (a-i) in primary root tips of 8-day-old T₁ transgenic seedlings grown in IRRI rice solution. The most intense GUS expression was mainly observed in columella (a), in columella and zone of elongation (b), in root cap (c), in root cap and basal meristematic zone (d), in root cap and protoxylem (e), in root cap, protoxylem and meristematic zone (f), in basal meristematic and elongation zones, absent in root cap and promeristem (g), evenly stained in root cap and meristematic zone (h), in root cap, stele and meristematic zone (i). Samples were stained for 30 min for (c)-(i) or 16 h for (a) and (b). Bar: 100 µm. (B) Images (a-i) shown on the right are magnifications of the corresponding images shown on the left (A) to provide detailed staining patterns in the apical root. Positions of columella cell (green arrow), quiescent center (red arrow) and xylem cell (yellow arrow) are indicated. Bar: 100 µm. (C) Three major staining patterns in lateral roots (a-c) from all the analyzed T₁ transgenic seedlings transformed by six DR5::GUS vectors. The most intense GUS expression was clearly observed in lateral root cap (a), in lateral root cap and xylem of both primary and lateral roots (b), in the whole vascular bundle and less specifically in the lateral root cap (c). Bars: 100 µm. (D) Patterns within T₁ transgenic seedlings of each vector were classified and presented as a heat map of percentage. Number of GUS positive T₁ seedlings observed for each vector is indicated in brackets.