title: Cyclin-dependent kinases participate in death of neurons evoked by DNA-damaging agents.
abstract: Previous reports have indicated that DNA-damaging treatments including certain anticancer therapeutics cause death of postmitotic nerve cells both in vitro and in vivo. Accordingly, it has become important to understand the signaling events that control this process. We recently hypothesized that certain cell cycle molecules may play an important role in neuronal death signaling evoked by DNA damage. Consequently, we examined whether cyclin-dependent kinase inhibitors (CKIs) and dominant-negative (DN) cyclin-dependent kinases (CDK) protect sympathetic and cortical neurons against DNA-damaging conditions. We show that Sindbis virus-induced expression of CKIs p16(ink4), p21(waf/cip1), and p27(kip1), as well as DN-Cdk4 and 6, but not DN-Cdk2 or 3, protect sympathetic neurons against UV irradiation- and AraC-induced death. We also demonstrate that the CKIs p16 and p27 as well as DN-Cdk4 and 6 but not DN-Cdk2 or 3 protect cortical neurons from the DNA damaging agent camptothecin. Finally, in consonance with our hypothesis and these results, cyclin D1-associated kinase activity is rapidly and highly elevated in cortical neurons upon camptothecin treatment. These results suggest that postmitotic neurons may utilize Cdk4 and 6, signals that normally control proliferation, to mediate death signaling resulting from DNA-damaging conditions.
authors.affiliation: Department of Pathology and Center for Neurobiology and Behavior, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA. dpark@uottawa.ca
authors.forename: D S
authors.initials: DS
authors.lastname: Park
authors.forename: E J
authors.initials: EJ
authors.lastname: Morris
authors.forename: J
authors.initials: J
authors.lastname: Padmanabhan
authors.forename: M L
authors.initials: ML
authors.lastname: Shelanski
authors.forename: H M
authors.initials: HM
authors.lastname: Geller
authors.forename: L A
authors.initials: LA
authors.lastname: Greene
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D042846:CDC2-CDC28 Kinases; D002166:Camptothecin / Q000494:pharmacology; D002453:Cell Cycle / Q000502:physiology; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D019938:Cyclin D1 / Q000235:genetics / Q000378:metabolism; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D051361:Cyclin-Dependent Kinase 6; D018844:Cyclin-Dependent Kinases / Q000235:genetics / Q000378:metabolism*; D003561:Cytarabine / Q000494:pharmacology; D004249:DNA Damage / Q000502:physiology*; D004789:Enzyme Activation / Q000187:drug effects / Q000528:radiation effects; D015967:Gene Expression Regulation, Viral; D009474:Neurons / Q000166:cytology* / Q000201:enzymology*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D051381:Rats; D017207:Rats, Sprague-Dawley; D012845:Sindbis Virus / Q000235:genetics; D017783:Superior Cervical Ganglion / Q000166:cytology; D014466:Ultraviolet Rays
chemical_list: D000964:Antimetabolites, Antineoplastic; D000972:Antineoplastic Agents, Phytogenic; D011518:Proto-Oncogene Proteins; D003561:Cytarabine; D019938:Cyclin D1; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495892:Cdk2 protein, rat; C495903:Cdk4 protein, rat; C495913:Cdk6 protein, rat; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D051361:Cyclin-Dependent Kinase 6; D018844:Cyclin-Dependent Kinases; D002166:Camptothecin