Figure 4—figure supplement 1

Figure 4—figure supplement 1

(A) Bright-field single-plane images of dorsal determinants removed (DD-removed) embryos at pharyngula stage (24 hpf). The proportion of embryos with a phenotype similar to the images shown is indicated in the lower right corner (n = 49, N = 4). The color-coded rectangles refer to the different phenotypic classes shown in (B). (B) Percentage of pharyngula stage DD-removed embryos displaying either a fully ventralized phenotype, some residual dorsal structures, both dorsal and head structures or various abnormalities (n = 49, N = 4). (C) High-resolution fluorescence images of control, DD-removed and animal pole explants 30 min after explant preparation stained for both β-catenin (grey) and DAPI (not shown). Both full projection and substack top views are shown to facilitate simultaneous visualization of the wounding site (yellow circle) and nuclear accumulation of β-catenin (yellow arrowheads). Insets are zoom-in images of the highlighted regions (dashed boxes). The proportion of blastoderm explants with a phenotype similar to the images shown is indicated in the lower left corner (control: n = 30, N = 6; DD-removed: n = 18, N = 4; animal pole: n = 10, N = 2). (D) Percentage of control (n = 30, N = 6), DD-removed (n = 18, N = 4) and animal pole (n = 10, N = 2) explants showing nuclear β-catenin staining 30 min after explant preparation. (E) High-resolution images of control (n = 84, N = 8), DD-removed (n = 44, N = 5) and animal pole (n = 27, N = 5) blastoderm explants at bud stage. In all cases, blastoderm explants were prepared from sebox::EGFP-expressing embryos (green) and are shown as side views. The proportion of blastoderm explants with a phenotype similar to the images shown is indicated in the lower right corner. (F) Percentage of control (n = 84, N = 8), DD-removed (n = 44, N = 5) and animal pole (n = 27, N = 5) blastoderm explants showing normal, reduced or no sebox::EGFP expression at bud stage (see Materials and methods for additional details). (G) Area of the sebox::EGFP domain in control (n = 84, N = 8), DD-removed (n = 44, N = 5) and animal pole (n = 27, N = 5) blastoderm explants at bud stage. ****p<0.0001 (Kruskal-Wallis test). (H) Area of the sebox::EGFP domain versus the normalized extension length in control (n = 77, N = 8), DD-removed (n = 44, N = 5) and animal pole (n = 27, N = 5) blastoderm explants at bud stage. Scale bars: 500 µm (A), 100 µm (C, E).

Figure 4—figure supplement 1—source data 1.