Fig 5. CIB1 inhibits Plk3 kinase activity in a calcium-dependent manner.

Autoradiogram analysis of in vitro kinase assay. (A) Phosphorylation of α-casein by Plk3 in the presence or the absence of CIB1. (B) Quantitation of the band intensity of A from more than three separate experiments (P=0.01). (C) Phosphorylation of α-casein by Plk3 (top panel) in the presence of Ca²⁺-stripped (apo-CIB1) or Ca²⁺-bound recombinant CIB1 or apo-CIB1 with Ca²⁺. Coomassie stained gel (bottom panel) is shown to indicate equal loading. Data shown is a representative autoradiograph of at least three separate experiments.