Genetic interactions between cdc23 and abp1. (A). The double mutant cdc23-M36 Δabp1 displays synthetic lethality at 30°C. Serial dilutions of cdc23-M36, Δabp1 and cdc23-M36 Δabp1, followed by incubation for 4 days at 25°C (upper panel) and 30°C (lower panel). (B). Cell cycle progression profiles of Δabp1, cdc23-M36 and cdc23-M36 Δabp1 at 30°C (from 1–6 hrs) and 25°C at time zero, by flow cytometry anaylsis. Both cdc23-M36 and cdc23-M36 Δabp1 show G1/S delay.