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DVDY_22386_sm_suppfig1.tif6584KSupp. Fig. 1. Echinoid (Ed) expression profile. A,A′: Stage 10 wild-type embryo stained for dp-ERK to highlight the tracheal placode (A) and Ed (A′). Ed is expressed uniformly in the tracheal placode (region surrounded by a dotted line in A′). B–B″: Stage 12 wild-type embryo stained for Armadillo (Arm; B) and Ed (B′; merge in B″ (Ed, green and Arm, red). Arm and Ed are expressed in all the trachea cells before fusion. C,C′: Stage 15 wild-type embryo stained for Arm (C) and Ed (C′) false-colored to show intensity (see scale of intensity levels at top right). Unlike Arm, Ed expression is not increased in the fusion cells (arrows, compare intensity levels). D: Stage 15 edM/Z embryo stained for Arm and false colored to show intensity levels. Arm expression is enriched in the fusion cells of edM/Z embryo in similarly to WT (arrows, compare intensity levels between C and D).
DVDY_22386_sm_suppfig2.tif4753KSupp. Fig. 2. Path length vs. distance. Wild-type embryo stained with WGA displayed as three different rotational views of a three-dimensional rendering (bottom left diagram displays the orientation of the X, Y, and Z axes). The path length described by the dorsal trunk between the transverse connectives of tracheal segments four to six (Path4-6) was measured by tracing a line through the tube following the three-dimensional aspects of the dorsal trunk (red line). The distance between the transverse connectives of tracheal segments four to six (Dist4-6) was measured by tracing a straight line between the start and finish point of the path (blue line).

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