Fig. 5. Elimination of tPA reduces Jun phosphorylation in Lurcher mice. Double immunofluorescence [against calbindin (red) and JunP (green)] was used to evaluate apoptosis of Purkinje cells (see quantitative data in Fig. 6A,B). Almost all of the cells were doubly-labeled in Lc/+ mice at P12, note the severe shrinkage of Purkinje cell bodies. By P30, hardly any Purkinje cells remained in Lc/+ mice. In Lc/+;tPA^–/– cerebella, there were few JunP-positive Purkinje cells at P12, and at P30 the Purkinje cells observed stained only with calbindin and not with JunP. Scale bar: 20 µm.