Fig. 2. The HLR gene is required for post-embryonic meristems. Structures of embryonic and post-embryonic meristems in wild type (A,C,E,G) and hlr-1 mutants (B,D,F,H). (A-D) Whole-mount preparations of the root apical meristem (RAM) in mature embryos (A,B), and in PI-stained root tips of 36-hour-old seedlings (C,D). White arrowheads indicate the quiescent center (QC). (E-H) Longitudinal sections of the shoot apical meristem (SAM) in mature embryos (E,F) and in 8-day-old seedlings (G,H). Black lines and arrowheads indicate the boundaries between cell layers and the irregular cell division planes, respectively. Scale bars: 25 µm.