Figure 4.

Cdk1 promotes gene recruitment to the nuclear periphery. (A) cdc28-1 mutant cells having the lac operator array at INO1 (■) or at GAL1 (▩) were grown under activating conditions at 22°C or shifted to 37°C for 2 h. (B) cdc28-1 mutant cells having the lac operator array at INO1 (■) or at GAL1 (▩) were grown under activating conditions at 22°C. Cells were then treated with nocodazole for 2 h and then either maintained at 22°C or shifted to 37°C for 30 min before quantifying gene localization. (C) Complementation of the cdc28-1 mutation by cloned CDC28. The cdc28-1 mutant was transformed with the indicated plasmids and tested for growth at either 22 or 37°C. (D) The cdc28-1 mutant transformed with CDC28 was tested for localization as in B. In A, B, and D, the blue, hatched line represents the level of colocalization of the lac repressor spot with the nuclear envelope predicted by chance (Brickner and Walter, 2004).