Fig. 2. pZLL:YFP-ZLL expression relative to the stem cell niche. (A) YFP-ZLL (yellow) accumulates in the apical cell of the 2-cell stage Arabidopsis embryo (blue, DAPI). (B,C) YFP-ZLL localisation relative to WUS-GFP₃ (green). (B) 16- to 32-cell stage embryo. (C) Early heart stage embryo. The dashed line indicates the uppermost layer of YFP-ZLL-expressing cells. (D,E) YFP-ZLL localisation relative to pCLV3:CFP-ER expression (cyan). (D) Early heart stage embryo. (E) Late heart stage embryo. The dashed line in E indicates the same boundary as in C. (F) Pro-vascular pATHB8:YFP-ZLL (yellow) expression does not overlap with pCLV3:CFP-ER (pink) or gWUS-GFP₃ (white) expression during embryogenesis. A torpedo stage embryo is shown. Insets show the differential contrast/fluorescent overlay. c, cotyledon; sam, shoot apical meristem; vp, vascular primordium; ad, adaxial cotyledon domain. Scale bars: 5 µm.