C. Bacterially expressed and purified His-PCM1 (a.a. 1-1128) was incubated with MBP alone or MBP-Plk4 (WT or KD) in vitro, and pulled down by magnetic beads coupled with an anti-MBP antibody, followed by staining with Coomassie Blue (left) or immunoblotting with an anti-His antibody (right). Asterisks show non-specific bands. The mobility difference between Plk4-WT and Plk4-KD was reported previously [43, 48]. We reproducibly observed the upward mobility shift of His-PCM1 upon binding to MBP-Plk4-WT, but not Plk4-KD. 