Fig. 6. Embryonic expression of the J2301 enhancer trap in wild-type, cpc, gl2 and wer mutants. (A) Confocal images showing the absence of GFP expression in gl2 mutant embryos carrying the J2301 enhancer trap dissected from the seed coat at different developmental stages. Scale bar, 60 µm. The dark green colour in whole embryos does not represent GFP expression. The image was obtained using and open iris and high gain during the collection of the optical sections with the confocal microscope in order to visualise the embryos. (B-G) Detection of GFP expression at the basal pole of mature wild-type, cpc and gl2 mutant embryos carrying the J2301 enhancer trap using confocal microscopy (B,D,F) and by in situ hybridisation (C,E,G). (B) In wild type, strong GFP expression was detected in cells at the basal end of the embryo, which in median longitudinal section (C) was shown to be precisely located in lateral root cap cells. In cpc embryos (D,E) and gl2 embryos (F,G) GFP expression was not detected. Scale bars: 60 µm.