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A cyclin A-protein kinase complex possesses sequence-specific DNA binding activity: p33cdk2 is a component of the E2F-cyclin A complex.

S H Devoto·M Mudryj·J Pines·T Hunter·J R Nevins
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Abstract

The E2F transcription factor has been found in association with the cyclin A protein, and this complex accumulates during the S phase of the cell cycle, suggesting that E2F may play a role in cell cycle control. In independent studies, cyclin A has been shown to be associated with two other proteins, the Rb-related p107 protein and the cdc2-related p33 cdk2 protein kinase. Through an analysis of the E2F-cyclin A complex, we now find that both the p107 protein and the cdc2-related p33cdk2 kinase are components of the previously described complex. Moreover, the complex possesses H1 kinase activity. These results thus define a cyclin A-cdk2 kinase complex that possesses sequence-specific DNA binding activity. This suggests that the cdk2 kinase may phosphorylate other DNA-bound substrates, and that one role of the E2F factor may be to localize this protein kinase to the DNA.

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3T3 CellsAnimalsBlotting, WesternCDC2-CDC28 KinasesCarrier ProteinsCell CycleCell Cycle ProteinsCell LineCyclin-Dependent Kinase 2Cyclin-Dependent KinasesCyclinsDNA-Binding ProteinsE2F Transcription FactorsHumansL CellsMacromolecular SubstancesMiceModels, StructuralProtamine KinaseProtein KinasesProtein Serine-Threonine KinasesRetinoblastoma-Binding Protein 1S PhaseTranscription Factor DP1Transcription FactorsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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S H Devoto, M Mudryj, J Pines, T Hunter, J R Nevins. 1992-01-10. A cyclin A-protein kinase complex possesses sequence-specific DNA binding activity: p33cdk2 is a component of the E2F-cyclin A complex.. https://doi.org/10.1016/0092-8674(92)90215-x

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