Mitogen-activated protein kinase kinase activity is required for the G(2)/M transition of the cell cycle in mammalian fibroblasts.
The mitogen-activated protein kinase (MAPK) cascade is required for mitogenesis in somatic mammalian cells and is activated by a wide variety of oncogenic stimuli. Specific roles for this signaling module in growth were dissected by inhibiting MAPK kinase 1 (MAPKK1) activity in highly synchronized NIH 3T3 cells. In addition to the known role of this kinase in cell-cycle entry from G(0), the level of MAPKK activity was observed to affect the kinetics of progression through both the G(1) and G(2) phases of the cell cycle in NIH 3T3 cells. Ectopic expression of dominant-negative forms of MAPKK1, which was previously shown to inhibit G(0)/G(1) progression, was found to also delay progression of cells through G(2). In addition, treatment of cells with the specific MAPKK inhibitor PD 98059 during a synchronous S phase arrested the cells in the following G(2) phase. These data demonstrate a novel role for the MAPK cascade in progression from G(2) into mitosis in NIH 3T3 cells.
Wright
J H
JH
Department of Pharmacology, University of Washington, Seattle, WA 98103, USA. jocelyn-wright@sugen.com
Munar
E
E
Jameson
D R
DR
Andreassen
P R
PR
Margolis
R L
RL
Seger
R
R
Krebs
E G
EG
D016475:3T3 Cells; D000818:Animals; D016203:CDC2 Protein Kinase / Q000502:physiology; D005419:Flavonoids / Q000494:pharmacology; D016195:G2 Phase; D048369:MAP Kinase Kinase 1; D051379:Mice; D020929:Mitogen-Activated Protein Kinase Kinases; D008938:Mitosis; D009154:Mutation; D011494:Protein Kinases / Q000502:physiology*; D017346:Protein Serine-Threonine Kinases / Q000502:physiology; D011505:Protein-Tyrosine Kinases / Q000502:physiology
D005419:Flavonoids; D011494:Protein Kinases; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D016203:CDC2 Protein Kinase; D048369:MAP Kinase Kinase 1; C482127:Map2k1 protein, mouse; D020929:Mitogen-Activated Protein Kinase Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one