Extended Data Fig. 2: Acquisition of the apical domain decreases surface tension and is sufficient for retaining PrE cells at the fluid interface.
From: Coupling of cell shape, matrix and tissue dynamics ensures embryonic patterning robustness
a. Analysis of surface cell circularity in E3.5 isolated ICMs to compare EPI and PrE cell shape. n = 53, 38 cells from 16 ICMs. Mann–Whitney U-test, p = 5.23e−07. b. Schematic diagram for the retention hypothesis, where PrE cells are retained at the fluid interface, whereas EPI cells are not. c. Representative immunofluorescence image of an isolated ICM at stage E3.5 showing distribution of PKCλ, and higher magnification images of PKCλ localization in EPI (GATA6-low, top) and PrE (GATA6-high, bottom) cells on the ICM surface. White arrowhead, PKCλ localization at the apical cortex in surface PrE cells. White asterisk, an EPI cell at the ICM surface. Yellow dotted line, cell boundary. d. Representative immunofluorescence image of an isolated ICM at stage E3.5 showing distribution of PKCζ, and higher magnification images of PKCζ localization in PrE (GATA6-high, top) and EPI (GATA6-low, bottom) cells on the ICM surface. White arrowhead, PKCζ localization at the apical cortex in surface PrE cells. White asterisk, an EPI cell at the ICM surface. Yellow dotted line, cell boundary. Scale bars, 20 μm; scale bars for zoomed-in panels, 10 μm.
