Figure 6. Cell adhesion is altered in Lis1 mutants and exacerbated by Dcx mutation.

Analysis of cell adhesion by IHC and in vitro functional assay. A) β-catenin staining at the apical surface of E14 brain sections is more diffuse in the mutants compared to WT, indicating a less tightly compacted and organized surface. Scale bars, 50 µm and 100 µm. B,C) Aggregation assay (TC and LTE treatments respectively, see methods) demonstrated a reduced capacity of Lis1^+/ko and Dcx^ko/Y neural progenitor cells to attach to each other and form aggregates. The Lis1^+/ko;Dcx^ko/Y double mutant displayed more severe defects in cell aggregation with smaller clusters that were spread all around the wells requiring the acquisition of several images for the quantification. The other genotypes had clusters accumulating at the center of the wells requiring one image for the quantification. D) For both treatments, we quantified the areas of the aggregates and found significant differences in the mutants compared to WT (**p-value<0.01; ***p-value<0.001). The panel WT (1 h, no Ca²⁺) in B is the negative control for the TC treatment, in which the absence of Calcium prevents the formation of the aggregates. Scale bar, 200 µm.