查看文章

Centrosome duplication is indispensable for the formation of the bipolar mitotic spindle. Surprisingly, even if DNA replication or mitosis is inhibited, centrosome duplication can still occur [1–5]. Thus, it remains unknown how centrosome duplication is coordinated with the cell cycle. Here, we show that centrosome duplication requires cyclin-dependent kinase 2 (Cdk2) in mammalian cells. We have found that in Chinese hamster ovary (CHO) cells, whereas centrosome duplication is not inhibited by hydroxyurea (HU) treatment, which arrests the cells in S phase, it is inhibited by mimosine treatment, which arrests the cells in late G1 phase. Cdk2 activity was higher in HU-treated cells than in mimosine-treated cells. Remarkably, inhibition of the Cdk2 activity in HU-treated cells with butyrolactone I or roscovitine [6], or by expression of the Cdk inhibitor p21^Waf1/Cip1, blocked the continued centrosome duplication …