Fig. 6: Apical actin meshwork is affected in the Cdh8/11 DKO cranial neural tube.
From: Redundant type II cadherins define neuroepithelial cell states for cytoarchitectonic robustness
a A section level for b, b′ in an E9.5 embryo is depicted. b Phalloidin staining is evaluated in the en face view of the E9.5 brain. b′ Expression patterns of Pax6 (a Fb marker) and Pax7 (a dorsal neural tube marker) are determined in the same sample. c Upper panels show enlarged view of apical surface actin meshwork at around the dorsal portion of the Fb and Mb indicated by dotted white frames in b, b′. Lower panels indicate semi-automated cell outlines generated in ImageJ. In all panels, top is the dorsal and bottom is the ventral side of the brain. Scale bar: 50 μm. d Cell number is counted within 0.01 mm2 apical area. All data points are shown along with the mean ± s.d. **P < 0.01; NS, non-significant. The number of cells significantly decreases in the Cdh8/11 DKO Mb, but not in the Fb. e Each apical area visualized by phalloidin staining is color coded based on the size (see right graph) and those areas larger than 301 μm2 are painted by the color code. Bold red lines delineate those clusters containing more than four adjacent cells with the painting. In Cdh8/11 DKO, cells with under 100 μm2 apical area decrease and those with larger apical area increase (graph). Additionally, those cells with less-constricted actin meshwork colored in the panel tend to cluster only in the Cdh8/11 DKO Mb. f Diagram hypothesizes how reduced apical constrictions could disrupt bending of the neural plate. Multiple loss of Cdh genes affects adherens junctions (green circles in WT; light green in DKO) to bring actin into less accumulated and constricted state (red belts in WT; pink in DKO) and occasionally increases cell proliferation. This disturbs bending kinetics of the neural plate, leading to exencephaly.
