title: MEKK1 is essential for DT40 cell apoptosis in response to microtubule disruption.
abstract: Vinblastine and other microtubule-damaging agents, such as nocodazole and paclitaxel, cause cell cycle arrest at the G2/M transition and promote apoptosis in eukaryotic cells. The roles of these drugs in disrupting microtubule dynamics and causing cell cycle arrest are well characterized. However, the mechanisms by which these agents promote apoptosis are poorly understood. We disrupted the MEKK1 kinase domain in chicken bursal B-cell line DT40 by homologous recombination and have shown that it is essential for both vinblastine-mediated apoptosis and vinblastine-mediated c-Jun N-terminal protein kinase activation. In addition, our data indicate that vinblastine-mediated apoptosis in DT40 cells requires new protein synthesis but does not require G2/M arrest, suggesting that vinblastine-mediated cell cycle arrest and apoptosis are two independent processes.
authors.affiliation: Molecular Biology Institute, University of California Los Angeles, Los Angeles, California 90095-1781, USA.
authors.forename: R
authors.initials: R
authors.lastname: Kwan
authors.forename: J
authors.initials: J
authors.lastname: Burnside
authors.forename: T
authors.initials: T
authors.lastname: Kurosaki
authors.forename: G
authors.initials: G
authors.lastname: Cheng
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D017209:Apoptosis; D015139:Blotting, Southern; D015153:Blotting, Western; D002453:Cell Cycle; D002460:Cell Line; D002645:Chickens; D003513:Cycloheximide / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005047:Etoposide / Q000494:pharmacology; D016195:G2 Phase; D015723:Gene Library; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases; D048728:MAP Kinase Kinase Kinase 1; D008870:Microtubules / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D008938:Mitosis; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism* / Q000502:physiology*; D017434:Protein Structure, Tertiary; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D015398:Signal Transduction; D013936:Thymidine / Q000494:pharmacology; D013997:Time Factors; D014162:Transfection; D014747:Vinblastine / Q000494:pharmacology
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004791:Enzyme Inhibitors; D019384:Nucleic Acid Synthesis Inhibitors; D011500:Protein Synthesis Inhibitors; D014747:Vinblastine; D005047:Etoposide; D003513:Cycloheximide; D017346:Protein Serine-Threonine Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048728:MAP Kinase Kinase Kinase 1; C482576:MAP3K1 protein, human; D013936:Thymidine