Fig. 7. Premature loss of the apical intercellular junctions in Hes1;Hes5 double-mutant spinal cord. (A-D) Sections of the wild type (A,C) and Hes1;Hes5 double mutant (B,D) at E9.5. Cells in the right and left walls of the double mutant are intermingled (D). (E,F) TEM analysis revealed the junctional complex at the apical side of the wild type (E, arrows). By contrast, the junctional complex is already lost in the Hes1;Hes5 double mutant (F, arrowheads). The boxed regions in C,D are enlarged. (G-I) Claudin-10 is expressed at the apical side of radial glia (nestin⁺) in the wild type. The en face view of the ventricular surface shows a ring-like distribution of claudin-10 (H). (J,K) TEM analysis shows the tight junction (kissing points are indicated by arrows in K) and adherens junction at the apical side in the wild type (J, brackets). (L-N) Claudin-18 is expressed at the apical side of radial glia (Ki67⁺) while neurons are located in the outer region (TuJ1⁺). (O-Q) In the double mutant, claudin-18 expression is lost in the ventral region, where radial glial cells are depleted (Q, arrow). This region is occupied by TuJ1⁺ neurons (P, arrow). Scale bars: 50 µm in A,B; 25 µm in C,D; 500 nm in E; 1 µm in F; 10 µm in G-I; 300 nm in J; 70 nm in K; 100 µm in L-Q.