Fig. 1. ß1 expression in the mouse and rat germinal neuroepithelium. (A-C) Expression of ß1 (A, red) and 6 (B, red) in the the E12.5 mouse VZ. Proliferative cells are revealed in C by labelling with an antibody against phosphorylated histone H3 (P-H3). Note that these cells are seen immediately adjacent to the ventricle, in the region where ß1 expression is highest. Nuclei in A and B (green) are counterstained with DAPI. (D-G) Proliferation of the ß1-expressing cells is shown directly in a section double labelled for P-H3 (green) and ß1 (red). Nuclei are shown counterstained with DAPI in D (blue), and a merged image is shown in F. (H-K) E12.5 mouse VZ cells adjacent to the ventricle and expressing high levels of ß1 (I) also express nestin (H, merged in J with DAPI shown in K). Note the extensive double labelling, whereas the developing blood vessel (arrowed) labels much more weakly with the anti-nestin antibody. (L-N) Some of the ß1⁺ cells observed two days after birth (P2) in the mouse VZ/SVZ (L) double label with nestin (M, merged image shown in N, arrow). (O) At P2 ß1⁺ cells are also prominent in the lateral wall of the ventricle in the rat. Note the elongated morphology and the lack of labelling in the medial wall. All sections are coronal. Scale bar: 15 µm in D-G,L-N; 20 µm in H-K,O; 25 µm in A,B; 30 µm in C.