(A and B) Strains were arrested in G1 with α factor and G2/M with nocodazole, and galactose was added to induce checkpoint fusions.
(C) Checkpoint fusions were induced in nocodazole-arrested isogenic wild-type and analog (1NM-PP1)-sensitive, cdc28-as, strains containing a LacO array. Both strains were treated as follows: inhibitor alone (5 uM), galactose plus inhibitor, and galactose alone.
(D) The strain carrying the cdc28-as allele, checkpoint fusions, and array was arrested with nocodazole and induced with galactose. After 3 hr, the culture was split and inhibitor was added.