Fig. 5. Abnormal Bergmann processes and aberrant astroglia in double null mutant cerebellar cortex after P5. (A-E) Immunostaining for GFAP at P5. (A,D) In controls, radial Bergmann processes form a well-defined cerebellar boundary (arrows). (B,C,E) In double mutants, Bergmann processes often extend beyond the pial surface (arrows in B,C), or they form thick end-feet processes without reaching the pial surface (E, also see inset). Moreover, in double null mutants, Bergmann processes often originate from cells that locate underneath the Golgi-cell/Purkinje-cell layer (arrowhead in E; the broken line indicates the position of the Purkinje cell layer). (F-I) Immunostaining for S100 at p5. Both control and null mutants show Bergmann processes and somata underneath the Purkinje cell layer (brown staining). (F,H) In controls, no positively staining somata are visible either in the intrafissural space (F, inset) or on the pial surface of the anterior lobes (H). (G,I) In double null mutants, positively staining somata are present in the intrafissural space and on the pial surface (arrows, G and inset). Occasionally, these S100-positive somata displayed long processes (arrow, I). PC, Purkinje cell layer; EGL, external germinal layer. GFAP and S100 were detected using a colorimetric immunoperoxidase reaction. Cells were counter-stained with Hematoxylin. Scale bars: 30 µm in A-E (15 µm in insets); 50 µm in F,G (25 µm in insets); 30 µm in H,I.
