Kinase experiment:

Purified 6xHis-tagged human Plk4 kinase domain is in 20 mM Tris pH 7.5, 100 mM NaCl, 10% glycerol, 1 mM DTT. 2X reaction buffer consists of 50 mM HEPES pH 8.5, 20 mM MgCl2, 1 mM DTT, 0.2 mg/mL BSA, 16 μM ATP, and 200 μM A-A11 substrate. The Plk4 concentration in the final reaction is 2.5-10 nM with a final pH of 8.0. Inhibitors (Centrinone) array in dose response are added from DMSO stocks. Reactions are allowed to proceed for 4-16 hours at 25℃. Detection is performed using ADP-Glo reagent. Luminescence is measured on an plate reader[1].

Cell experiment:

For each condition, cells are seeded in triplicate into 6-well plates at 50,000 cells/well. 125 nM Centrinone (LCR-263) is added to HeLa cells or 300 nM is added to NIH/3T3 cells. At 24-hour intervals, 3 wells are harvested per condition. Cell counting is performed using a TC10 automated cell counter[1].

Centrinone (LCR-263) is a selective and reversible inhibitor of polo-like kinase 4 (PlK4) with a Ki of 0.16 nM.

Centrinone (LCR-263) exhibits more than 1000-fold selectivity for Plk4 over Aurora A/B and does not affect cellular Aurora A or B substrate phosphorylation at concentrations that deplete centrosomes. Centrinone (LCR-263) treatment of HeLa human cervical carcinoma cells leads to a progressive reduction in foci containing centriolar and pericentriolar material markers at each round of cell division, until most cells lack centrioles and centrosomes. Treatment with Centrinone (LCR-263) reduces centriole number in multiciliated Xenopus epithelial cells, which indicates that Plk4 also controls centriole amplification in differentiated cells. Centrinone (LCR-263) treatment causes centrosome depletion in human and other vertebrate cells. Centrosome loss irreversibly arrests normal cells in a senescence-like G1 state by a p53-dependent mechanism that is independent of DNA damage, stress, Hippo signaling, extends mitotic duration, or segregation errors[1].

[1]. Wong YL. et al. Cell biology. Reversible centriole depletion with an inhibitor of Polo-like kinase 4. Science. 2015 Jun 5;348(6239):1155-60.