Fig. 5. Temporal and spatial patterns of HB-EGF staining in E13 (A) and E16 mouse (B,C). At E13 (A), HB-EGF immunoreactivity was seen at the ventricular surface. By contrast, at E16 (B), staining was most intense in two additional layers, corresponding to the marginal zone (MZ) and subplate/white matter (SP/WM). Diffuse staining was also visible in the intermediate zone (IZ). VZ, ventricular zone; SVZ, subventricular zone. Staining was more intense laterally (L) than medially (M) (B,C). (D) Western blot of lysates of E16 mouse dorsolateral cortex probed with anti-HB-EGF. Lane 1, recombinant HB-EGF (R&D); lane 2, E16 lysate.