Fig. 1.

Centrinone is a selective Plk4 inhibitor that reversibly depletes centrioles from cells. (A) Chemical structures, K_i values, and selectivities [Plk4 versus Aurora A/B; Ki (kinase)/Ki (Plk4)] of the centrinones and VX-680 (B) Crystal structure of the centrinone-Plk4 kinase domain complex (orange αC helix). (C) Close-up of centrinone in the Plk4 active site. The aminopyrazole moiety of centrinone hydrogen bonds (orange dashes) with the main chain carbonyl of Glu⁹⁰ and the carbonyl and amide nitrogen of Cys⁹². The 5-methoxy substituent (magenta spheres) packs against the Met⁹¹ side chain (magenta stick and gray spheres). The benzyl sulfone moiety (orange surface) wraps around Lys41 (orange). (D) HeLa cells 7 days after centrinone addition and 10 days after centrinone washout. (Insets: 3.3× magnified). Scale bar, 10 mm. Schematic shows progressive centrosome depletion after Plk4 inhibition. Bar graph shows the centrosome number distribution after centrinone addition and washout. (E) g-Tubulin foci in NIH/3T3 cells induced to overexpress wild-type or centrinone-resistant (G95L) Plk4-GFP. Scale bar, 5 mm. Data in (D) and (E) are means T SD; number of experiments (N) = 3.