FIGURE 2.

Epidermis migration and AM pore movement. (A) Maximum intensity projections of stacks of confocal images from time lapse recordings of left (top) and head-on (bottom) views of epidermis movement and movement of AM pores during lima bean stage. See also Supplementary Video 3. (B) Same as panel (A), however, stage is lima bean to 1.5-fold stage. (C) Lateral view of embryos before and after UV laser ablation of the epidermis close to the AM pore. White dashed lines highlight the epidermal front. White arrowheads point to the position of the AM pore, and yellow arrowheads mark the position of the pore close to the ablated epidermis. Yellow circle marks the position of the laser ablation. See also Supplementary Video 4. (D) Quantification of epidermis ablation experiments (n = 4). The relative distance of the ablated (red) and un-ablated (black) AM pores to the mouth was measured. P-values from a multiple unpaired t-test and with two-stage linear step-up procedure (Benjamnini, Kreiger, and Yekutieli) are shown (*≥0.05; **≥0.01). (E) Left and middle: Schematic depicting the spreading of the epidermis around the head (head enclosure) and the initial and final positions of the sensory organ pores. Note that only the AM pores are located at the anterior epidermal edge. Right: Schematic depicting a juxta-oral cross section that highlights the symmetry of sensory organ pores and the symmetry of the pharynx.