Fig. 3
HySp5 antagonizes Wnt/β-catenin signaling in Hydra. a Double knockdown of Sp5 and β-catenin. Animals were pictured live on day-8 in two independent experiments. RNAi: siRNA electroporation day. Red arrows: ectopic heads; white arrows: bumps. b Knockdown of Sp5 and β-catenin in ALP-treated animals. Upper panel: Morphological changes observed in animals fixed at day-7. Lower panel: Quantification of ectopic tentacles formed at day-7. Each dot represents the number of ectopic tentacles in one animal (two biologically independent experiments). c Intact Hydra exposed to siRNAs and ALP as indicated and detected for Wnt3 by WISH (upper panel) and qPCR (lower panel). Blue arrows: RNA extraction days; black arrows: local increase in Wnt3; black arrowhead: diffuse increase in Wnt3 expression. Each data point represents one biologically independent experiment. d Effect of Sp5 knockdown on head patterning during the process of reaggregation initiated on day-4 (black arrow). Aggregates were pictured live (upper row), then fixed to detect Wnt3 expression (lower row) in two independent experiments. e Quantification of Wnt3 expressing clusters. Each dot represents the number of Wnt3+ clusters in one aggregate. Statistical p values: *P ≤ 0.05, **p ≤ 0.01, ****p ≤ 0.0001 (unpaired t test). Scale bars in panels a–d: 200 μm. Error bars indicate SD
