Manipulating the onset of cell cycle withdrawal in differentiated erythroid cells with cyclin-dependent kinases and inhibitors.
Terminal differentiation of erythroid cells results in terminal cell divisions followed by irreversible cell cycle withdrawal of hemoglobinized cells. The mechanisms leading to cell cycle withdrawal were assessed in stable transfectants of murine erythroleukemia cells, in which the activities of cyclin-dependent kinases (CDKs) and CDK inhibitors (CDKIs) could be tightly regulated during differentiation. Cell cycle withdrawal of differentiating cells is mediated by induction of several CDKIs, thereby leading to inhibition of CDK2 and CDK4. Manipulation of CDK activity in differentiating cells demonstrates that the onset of cell cycle withdrawal can be either greatly accelerated or greatly delayed without affecting hemoglobin levels. Extending the proliferation of differentiating cells requires the synergistic action of CDK2 and CDK4. Importantly, CDK6 cannot substitute for CDK4 in this role, which demonstrates that the 2 cyclin D-dependent kinases are functionally different. The results show that differentiating hemoglobinized cells can be made to proliferate far beyond their normal capacity to divide. (Blood. 2000;96:2755-2764)
Matushansky
I
I
Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Radparvar
F
F
Skoultchi
A I
AI
D000081:Acetamides / Q000494:pharmacology; D000818:Animals; D042846:CDC2-CDC28 Kinases; D002453:Cell Cycle / Q000187:drug effects*; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D051361:Cyclin-Dependent Kinase 6; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D004790:Enzyme Induction; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D015672:Erythroid Precursor Cells / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D015973:Gene Expression Regulation, Leukemic; D005816:Genetic Complementation Test; D006454:Hemoglobins / Q000096:biosynthesis; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute / Q000473:pathology; D051379:Mice; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D011518:Proto-Oncogene Proteins; D011993:Recombinant Fusion Proteins / Q000502:physiology; D014162:Transfection
D000081:Acetamides; D004791:Enzyme Inhibitors; D006454:Hemoglobins; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D011993:Recombinant Fusion Proteins; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; C495900:CDK4 protein, human; C495911:CDK6 protein, human; C495893:Cdk2 protein, mouse; C495902:Cdk4 protein, mouse; C495912:Cdk6 protein, mouse; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D051361:Cyclin-Dependent Kinase 6; D018844:Cyclin-Dependent Kinases; C014026:hexamethylene bisacetamide