Fig. 7. GDI1 is involved in the regulation of the contractile vacuole. Confocal immunofluorescence images of cells grown overnight on coverslips in axenic medium, fixed with picric acid/paraformaldehyde and immunostained with mAb 221-35-2 (a marker of membranes of the contractile vacuole and the endo/lysosomal system). (A) Staining around the numerous large vacuoles of a GDI^– giant cell. Normal-sized mutant cells (B) display larger vacuoles as compared with the wild-type strain (C). Scale bars are 10 µm.