Recombinant human PLK4 (1-836) was expressed by baculovirus in Sf9 insect cells using an N-terminal GST tag. PLK4 or polo-like kinase 4 is a member of the polo family of serine/threonine protein kinases which localizes to centrioles, complex microtubule-based structures found in centrosomes, and regulates centriole duplication during the cell cycle. The overexpression of PLK4 triggered the simultaneous formation of multiple procentrioles around each preexisting centriole which resulting in centriole amplification and thus, Plk4-induced centriole biogenesis in human cells. ADP-Glo Kinase Assay is a luminescent kinase assay that measures ADP formed from a kinase reaction; ADP is converted into ATP, which is a substrate in a reaction catalyzed by Ultra-Glo Luciferase that produces light. The luminescent signal positively correlates with ADP amount and kinase activity. The assay is well suited for measuring the effects chemical compounds have on the activity of a broad range of purified kinases, making it ideal for both primary screening as well as kinase selectivity profiling. The ADP-Glo Kinase Assay can be used to monitor the activity of virtually any ADP-generating enzyme (e.g., kinase or ATPase) using up to 1mM ATP.