title: Cdk pathway: cyclin-dependent kinases and cyclin-dependent kinase inhibitors.
abstract: Many mechanisms either activate or inhibit the cdks and thereby either promote or arrest progression through the mitotic cell cycle. Since the signal transduction pathways emanating from extracellular mitogens and the agents controlling these pathways are complicated there may yet be novel mechanisms of cell cycle regulation remaining to be elucidated. In this article we outline the different techniques used to study the cell cycle and its regulation. These include: establishing that the cell cycle is arrested by propidium iodide staining followed by FACS analysis or by measuring 3H-thymidine incorporation into DNA; measuring the amount of cyclin/cdk associated kinase activity; assessing the steady-state expression profiles of cyclins, cdks and ckis by immunoblotting; and investigating the formation of complexes between these proteins by coimmunoprecipitations. Caveats and advantages of each technique are discussed. Following this paradigm yielded the discovery of the cell cycle inhibitors p27Kip1 and p21Cip1 and could very well lead to the discovery or novel cell cycle regulatory mechanisms.
authors.affiliation: Box 207, Room RRL 917a, Sloan-Kettering Institute, 1275 York Avenue, New York, NY, USA. dmgitig@hotmail.com
authors.forename: D M
authors.initials: DM
authors.lastname: Gitig
authors.forename: A
authors.initials: A
authors.lastname: Koff
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000378:metabolism; D002469:Cell Separation; D004396:Coloring Agents / Q000494:pharmacology; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D016213:Cyclins / Q000378:metabolism; D004247:DNA / Q000032:analysis; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005434:Flow Cytometry; D005982:Glutathione Transferase / Q000378:metabolism; D015151:Immunoblotting; D051379:Mice; D008954:Models, Biological; D010766:Phosphorylation; D011233:Precipitin Tests; D011419:Propidium / Q000494:pharmacology; D011494:Protein Kinases / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000378:metabolism; D015398:Signal Transduction; D013936:Thymidine / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000378:metabolism
chemical_list: C493957:Cdkn1a protein, mouse; C493961:Cdkn1b protein, mouse; D018797:Cell Cycle Proteins; D004396:Coloring Agents; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D016160:Retinoblastoma Protein; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D011419:Propidium; D004247:DNA; D005982:Glutathione Transferase; D011494:Protein Kinases; C102333:histone H1 kinase; D018844:Cyclin-Dependent Kinases; D013936:Thymidine