The cyclin D1-dependent kinase associates with the pre-replication complex and modulates RB.MCM7 binding.
The capacity of the cyclin D-dependent kinase to promote G(1) progression through modulation of RB.E2F is well documented. We now demonstrate that the cyclin D1/CDK4 kinase binds to components of the MCM complex. MCM7 and MCM3 were identified as cyclin D1-binding proteins. Catalytically active cyclin D1/CDK4 complexes were incorporated into chromatin-bound protein complexes with the same kinetics as MCM7 and MCM3, where they associated specifically with MCM7. Although the cyclin D1-dependent kinase did not phosphorylate MCM7, active cyclin D1/CDK4, but not cyclin E/CDK2, did catalyze the dissociation of an RB.MCM7 complex. Finally, expression of an active D1/CDK4 kinase but not cyclin E/CDK2 promoted the removal of RB from chromatin-bound protein complexes. Our data suggest that D1/CDK4 complexes play a direct role in altering an inhibitory RB.MCM7 complex possibly allowing for setting of the origin in preparation for DNA replication.
Gladden
Andrew B
AB
Leonard and Madlyn Abramson Family Cancer Research Institute, Department of Cancer Biology, Abramson Family Cancer Center of the University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Diehl
J Alan
JA
D016475:3T3 Cells; D000818:Animals; D002384:Catalysis; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002460:Cell Line; D002843:Chromatin / Q000378:metabolism; D056741:Cyclin D; D019938:Cyclin D1 / Q000378:metabolism*; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D016213:Cyclins / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D007313:Insecta; D007700:Kinetics; D051379:Mice; D008856:Microscopy, Fluorescence; D064168:Minichromosome Maintenance Complex Component 7; D009687:Nuclear Proteins / Q000378:metabolism*; D010766:Phosphorylation; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011518:Proto-Oncogene Proteins; D016160:Retinoblastoma Protein / Q000378:metabolism*; D013997:Time Factors; D014162:Transfection; D020798:Two-Hybrid System Techniques
D018797:Cell Cycle Proteins; D002843:Chromatin; D056741:Cyclin D; D016213:Cyclins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D016160:Retinoblastoma Protein; D019938:Cyclin D1; C495902:Cdk4 protein, mouse; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases; C491086:Mcm7 protein, mouse; D064168:Minichromosome Maintenance Complex Component 7