Focal disruptions at the basement membrane are correlated with disorganized radial glia. Immunofluorescent detection of perlecan (red) and brain-lipid binding protein (BLBP; green) in control (A, C) and nestin-Cre/DG-null cerebella (B, D) on the day of birth (P0) and at P3. Immunofluorescent staining of glial fibrillary acidic protein (GFAP; red) and laminin (LM; green) in control (E) and nestin-Cre/DG-null littermate (F) at P8. Immunostaining of β1-integrin (β1Itg, green) in control (G) and nestin-Cre/DG-null cerebella (H) at P21. In control cerebella, radial glia (Bergmann glia at P8) endfeet abut an intact basement membrane (carets), forming the continuous glia limitans. In the absence of DG, disruptions at the basement membrane are often found in areas of disorganized radial glia throughout development (tildes; ~). β1Itg is normally expressed in Bergmann glia in both control and nestin-Cre/DG-null cerebella. However, β1Itg expression appears to be upregulated at areas of gliosis (asterism; ⁂), along with ectopic cells (asterisks; *) and disrupted glia limitans (tildes; ~). DAPI (blue) was used as nuclear counter stain. Scale bar: 20 μm.