FIGURE 9.

Activated CDK1 induces degradation of MLST8 and decreases binding with FBXW7 and MLST8. A, Evaluation of antibodies against phospho‐Thr50‐MLST8 (p‐T50‐MLST8). WT‐MLST8‐myc or T50A‐MLST8‐myc were transiently expressed in HEK293 cells. B, Thr50 of endogenous MLST8 protein is phosphorylated in 786‐O cells. Endogenous MLST8 protein was depleted by MLST8‐sgRNA, and lysates were subjected to immunoblotting with the indicated antibodies. C, Putative consensus motif for phosphorylation by CDK1 and CDK2 in the CPD motif containing Thr50 in MLST8. D and F, Thr50 in MLST8 is efficiently phosphorylated by CDK1 in vitro. G, Thr50‐phosphorylated MLST8 binds FBXW7 in vitro. Purified GST‐fused WT‐ or T50A‐MLST8 or GST protein using glutathione beads was incubated with or without recombinant CDK1 in reaction buffer containing 1 mM ATP for 30 min