Extended Data Fig. 2: Differential adhesion force in ETX embryos.
From: Stem cell-derived synthetic embryos self-assemble by exploiting cadherin codes and cortical tension
(a) Representative images of cell doublets for homotypic and heterotypic cell pairs (green, Gata4; cyan, Tfap2c; gray, Oct4; red, F-actin). Experiments were repeated 3 times. Scale bar is 10 μm. (b) Use of ImSAnE ‘Unrolling’ algorithm to project 3D E-cadherin staining stacks onto a 2D plane. Cell contact angles were quantified using built-in correction methods. Geometric observables as well as generally distortions in projections can be correctly quantified. Scale bar is 100 μm. (c) Cell-cell contact angle measurements based on ImSAnE method in day 4 ETX and E5.5 natural embryos. Total measured cell pairs in ETX embryos: ES-ES: n = 24; TS-TS: n = 15; XEN-XEN: n = 16; ES-TS: n = 24; XEN-TS: n = 19; XEN-ES: n = 16; XENi-XENi: n = 16. Total measured cell pairs in natural embryos: EPI-EPI: n = 20; TE-TE: n = 17; VE-VE: n = 22; EPI-TE: n = 24; EPI-VE: n = 16; TE-VE: n = 19; VEi-VEi: n = 24. Data are presented as box-whisker plots, black line inside the box indicates the median value and the error bar shows min to max value. Statistics calculated by one-way ANOVA with a multiple comparison test. (d) Enlargement of the boundary area in a day4 ETX embryo stained with E-cadherin, with homotypic contacts highlighted in blue (TS-TS), red (ES-ES) and purple (XEN-XEN), and the heterophilic boundary interface in yellow. Angles formed at tricellular junctions between different types are indicated: EX, TX and ET, angles between heterotypic contacts (ES-XEN, TS-XEN and ES-TS); EE, TT and XX, angles between homotypic contacts (ES-ES, TS-TS and XEN-XEN). XXi indicates contact angles of XEN cells at cell-medium interface. Experiments were repeated 6 times. Scale bar represents 20 μm. (e) E-cadherin and P-cadherin mRNA expression in cells after downregulation of E- or P-cadherin by RNAi, scrambled siRNA was used as a control. P-cadherin mRNA expression in ES cells after overexpression of P-cadherin. N = 4 for all conditions. Data are presented as mean ± SD. Statistics calculated by unpaired two-tailed Student’s t test. Source numerical data are available in source data.
