Cyclin-dependent kinase 2 (Cdk2) is required for centrosome duplication in mammalian cells.
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] [2] [3] [4] [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. Moreover, overexpression of Cdk2 reversed the inhibition of centrosome duplication by mimosine treatment. These results indicate a requirement of Cdk2 activity for centrosome duplication and therefore suggest an underlying mechanism for the coordination of centrosome duplication with the cell cycle.
Matsumoto
Y
Y
Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
Hayashi
K
K
Nishida
E
E
D015107:4-Butyrolactone / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D042846:CDC2-CDC28 Kinases; D016466:CHO Cells / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D002453:Cell Cycle / Q000187:drug effects; D018385:Centrosome / Q000187:drug effects / Q000378:metabolism*; D006224:Cricetinae; D051357:Cyclin-Dependent Kinase 2; D050759:Cyclin-Dependent Kinase Inhibitor p21; D018844:Cyclin-Dependent Kinases / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D016213:Cyclins / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016193:G1 Phase / Q000187:drug effects; D015870:Gene Expression; D006918:Hydroxyurea / Q000494:pharmacology; D008898:Mimosine / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D011687:Purines / Q000494:pharmacology; D000077546:Roscovitine; D016196:S Phase / Q000187:drug effects
D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D011687:Purines; D000077546:Roscovitine; D008898:Mimosine; C082868:butyrolactone I; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases; D015107:4-Butyrolactone; D006918:Hydroxyurea