ALT Figure 4: Phenotype rescue upon Zic4 and Gata3 double knockdown. Maximum projection confocal images of oral (A) and aboral (B) ends of animals after GFP RNAi (control), Zic4 or Gata3 RNAi, and Zic4 Gata3 RNAi. DNA in cyan, peroxidase activity in magenta and Nematocilin in orange. Panels on the right show magnifications of boxed areas on the left. Scale bars: 100μm. (C) Percentage of animals with ectopic peroxidase staining in tentacles upon Zic4 KD and double KD. (D) Percentage of animals with ectopic Nematocilin staining adjacent to the foot in Gata3 KD and double KD. ***P<0.001 (Fisher's exact test). (E,F) At the oral pole, Wnt signaling (black dot) activates Zic4 (orange) expression and thus basal disk identity. Without it, Gata3 dominates at the opposite end, leading to basal disk fate establishment (E). Experimentally depleting one of the factors results in ectopic cell fate acquisition at the opposite body end (F).