Fig. 7

Precise control of apical contractility is required for apical clearance.

Acute DMSO (A) or Y-27632 (B) treatment on rasip1 mutants with unopened cell-cell contact sites. Red arrowheads indicate the same junctional patches/rings at 20 minutes and 80 minutes after drug treatment. C The Cdh5 boundary-to-apical ratio in the following groups: WT + DMSO (n = 11 cells from 5 embryos), WT + Y-27632 (n = 11 cells from 5 embryos), rasip1 + DMSO (n = 10 cells from 5 embryos), rasip1 + Y-27632 (n = 10 cells from 6 embryos) at 200 minutes after treatment for newly opened junctions. Data are presented as mean ± SD. ***P = 0.0005, 2-tailed unpaired t-test. D Myl9a-GFP and Cdh5-Venus at 20 minutes and 80 minutes after acute Y-27632 treatment (75 μM) in rasip1^ubs28 mutants. White arrows label ectopic apical Myl9a and Cdh5, while white arrowheads mark junctional Myl9a at 80 minutes post-treatment. Consistent observations were made across 8 samples from 3 independent experimental setups. E The Cdh5 boundary-to-apical ratio over the acute treatments in the following groups: WT + DMSO (n = 16 cells from 6 embryos), rasip1 + DMSO (n = 20 cells from 6 embryos), rasip1 + Y-27632 (n = 10 cells from 4 embryos). Data are presented as mean ± SD. F Wild-type embryos expressing Scarlet-I-Podxl1 or N-ROCK1-Scarlet-I-Podxl1 (F) and corresponding diagram (F”). (F’) Intensities of Cdh5-Venus and Scarlet-I-Podxl1 or N-ROCK1-Scarlet-I-Podxl1 along the dashed lines in (F). White arrowheads label enriched N-ROCK1-Scarlet-I-Podxl1 and Cdh5 within the apical domain. G Quantification of the Cdh5 boundary-to-apical ratio in wild-type embryos expressing Scarlet-I-Podxl1 (n = 17 cells from 9 embryos) or N-ROCK1-Scarlet-I-Podxl1 (n = 20 cells from 8 embryos). Data are presented as mean ± SD. ***P < 0.0001, 2-tailed unpaired t-test. H, I Activation of Opto-RhoA selectively at the apical compartment (H) and corresponding diagram (I). White arrowheads label apical Cdh5 and Opto-RhoA clusters. (H’) Intensities of Cdh5-Venus and Opto-RhoA-mCherry along the dashed lines in (H). All scale bars: 10 μm. Source data are provided as a Source Data file.