Figure 4. Clb2-Cdk1 remains active post nuclear division in the absence of MCK1. CLB2-HA and CLB2-HA mck1∆ strains were arrested in G₁ with mating pheromone. Time points were taken at 25, 45, 65, 85, 105 and 125 min following release and processed for kinase assays (A) and western blots (C). (A) Clb2-HA was IP’d from wild type (CLB2-HA) and mck1∆ (CLB2-HA mck1∆) strains. (C) Western blot analysis of Clb2-HA IP from (A) and WCE probed with the following antibodies as indicated: anti-HA, anti-phospho-cdc2 (Tyr15) and anti-PSTAIR (Cdk1). (B and D) Relative intensities of indicated bands relative to the WCE Cdk1 protein band in (C). The experiment was performed three times, and representative kinase assays and blots are shown.