Fig. 1. hGfap-Cre-mediated Pten deletion leads to macrocephaly and cerebella layering defects. (A) Significant increase of brain mass of hGfap-cre^+/–;Pten^loxp/loxp mice at P21. (B) Western blot analysis of protein extracts from freshly isolated granule neurons and cerebellar glia at P6. Both granule neurons and glia of Pten mutant showed a significant decrease in PTEN expression, accompanied by increased P-AKT levels. (C, a-d') The sagittal sections revealed a significant increase in size of the cerebella of Pten mutants by Hematoxylin and Eosin staining (rostral is upwards and anterior is towards the left). Mutants also showed the loss of foliation and the disruption of the IGL after P6 (C, c',d'). (D, a'-d') Calbindin immunostaining showed Purkinje cells misplacement in Pten mutant mice over time. At P3, Purkinje cell layer was relatively normal in mutant mice (D, b'). At P9, many ectopic Purkinje cells were seen in Pten mutants (D, d'). Scale bar: 100 µm.