Fig. 5

Reduction in Blastoderm Surface Tension Is Required and Sufficient to Trigger Doming

(A–H) Intact WT (n = 6 embryos) (A) and (B) and pky embryos (n = 3 embryos) (C) and (D) and embryos where EVL/surface cells were transplanted from pky to WT embryos (E) and (F) (n = 10 embryos) and from WT to pky embryos (G) and (H) (n = 9 embryos). Bright-field images of mosaic embryos before (−30 min) and after completion of doming (+90 min) with transplanted cells marked by fluorescent dextran; green (A), (A′), (C), (C′), (E), (E′), (G), and (G′). Confocal images with plasma membrane expressing mem-GFP (green), nuclei marked by H2A-mCherry (magenta) and BYI outlined by fluorescent dextran (white); (A″), (A‴), (C″), (C‴), (E″), (E‴), (G″), and (G‴). Transplanted cells were marked by fluorescent dextran; green (E), (E′), (G), and (G′), or H2B-GFP; green (E″), (E‴), (G″), and (G‴). Red and white dashed lines, BYI. Changes in relative BYI area (left column) and relative EVL/surface cell area (middle column) as a function of time during doming in the different transplantation experiments (B), (D), (F), and (H). Note that the results from control experiments (WT into WT [n = 3 embryos] and pky into pky [n = 3 embryos]) were included in the plots as reference (F) and (H), see also Figures S5D–S5G, and that changes in relative EVL area in the transplantation experiments were determined exclusively in the region of the blastoderm where the transplanted cells were located. The WT data in (B) and (D) is the same as Figures 1G and 1J. Error bars, ±SEM. Scale bars, 100 μm.

See also Figures S5 and S6; Movie S5.