Figure 2.

Abnormal formation/development of the cerebellum in Bmpr1a;Bmpr1b double knock-out mutants. A, Nissl staining on coronal sections shows the normal cerebellum at P0 (arrow). B, The cerebellum of the mutant mouse is smaller in size at P0 (arrow). C, E, Nissl staining show defined layers including the EGL and PCL in normal P0 neonates. The ML is the cell-sparse layer between the EGL and PCL. D, F, In the mutant cerebellum, disruption of the layered organization is observed. Only a small region with the thickened EGL (arrow) is observed, but most of the mutant cerebellum completely lacks the EGL and PCL, the presumptive position of which is indicated in F. E, High-magnification view of C. F, High-magnification view of D. Scale bars: C, E, 250 μm.