(D-I) The CIBN::GFP-pm signal was used to reconstruct cell shape in 3D as described in the STAR Methods. Representative examples (18 ≤ n ≤ 136) of reconstructed cell shapes in the non-activated region at the initial time point (D), 3 min (E) and 10 min (F) after photo-activation show that the cells undergo apical constriction and the characteristic transition from a columnar to a conic shape. In contrast, representative examples (83 ≤ n ≤ 133) of reconstructed cell shapes in the activated region at the initial time point (G), 3 min (H) and 10 min (I) reveal that photo-activated cells did not undergo stereotypic cell shape changes and remain columnar 