Fig. 1. Phenotypes of cs scn1 and scn2 mutants. (A) Fission yeast scn1 and scn2 are extragenic suppressors for ts cut9-665 that causes the assembly defect in APC/C (Samejima and Yanagida, 1994; Yamada et al., 1997). Single cut9 mutant fails to form colonies at 33°C, whereas double mutants cut9 scn1 and cut9 scn2 form colonies at 33°C. Single scn1 and scn2 mutants are unable to form colonies at 22°C. (B) Wild-type, scn1 and scn2 grown at 33°C were transferred to 20°C and cultured for 50 hours in the complete YPD medium. The cell number of wild-type (WT), scn1 and scn2 mutants was scored. (C) The cell length of wild-type (hatched columns) and scn1 mutant (red columns) was measured after 0 and 24 hours culture at 20°C. The average cell length of wild-type and scn1 mutant is indicated. (D) Light micrographs of wild-type and scn1 mutant cells cultured at 20°C for 9 hours. Wild-type and scn1 mutant cells were cultured at 20°C, fixed with glutaraldehyde and stained with DAPI. The arrows indicate the displaced divided nuclei abundantly present in scn1 and scn2 mutant cells. Bar, 10 µm.