Fig. 4. LEF-1 activity is essential to maintain the CR in P. sinensis. (A) Transverse section of the CR after electroporation of the GFP construct. Its expression is restricted to the epidermis. (B) Whole-mount embryo 4 days after the electroporation of GFP. No morphological changes are observed at the site of the operation (arrowhead). (C) Four days after the electroporation of dominant-negative LEF-1, a notch in the CR (arrowhead) appears at the site of electroporation, showing the local arrest of CR growth. Scale bars: 50 µm for A, 1 mm for B,C.