Fig. 7. hydkk1/2/4 expression in alsterpaullone (AP)-treated animals. Polyps were incubated for 24 hours in 5 µM AP and then transferred to Hydra medium for time indicated. (A) Dark-field micrographs. (B) Quantification of hydkk1/2/4 expression (white squares) and tentacle formation (black circles) from three independent experiments, determined as the percentage of hydkk1/2/4-expressing polyps and the number of tentacles from a total of 120 polyps. Bars indicate s.d.; solid line indicates the length of AP treatment. (C) ISH with an antisense hydkk1/2/4 probe (for details see Results).