RRC ID 41478
著者 Takahashi K, Inanami O, Hayashi M, Kuwabara M.
タイトル Protein synthesis-dependent apoptotic signalling pathway in X-irradiated MOLT-4 human leukaemia cell line.
ジャーナル Int J Radiat Biol
Abstract PURPOSE:To demonstrate whether protein synthesis is required for ionizing radiation-induced apoptosis through activation of caspases in human leukaemia cell line MOLT-4, the effects of a protein synthesis inhibitor, cycloheximide, on the apoptotic signalling pathway including the activation of caspase family and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), and the expression of Fas/CD95/APO-1 (Fas) were examined in X-irradiated MOLT-4 cells.
MATERIALS AND METHODS:MOLT-4 cells pretreated with 0.5 microg/ml cycloheximide for 1h were exposed to 7.5Gy of X-rays. The appearance of apoptosis, expression of Fas, activation of caspases-3, -8, -9, SAPK/JNK and AP-1, the release of mitochondrial cytochrome-C and the formation of death-induced signalling complex (DISC) between Fas and the Fas-associated death domain (FADD) were measured by fluorescence microscopy, Western blotting, flow cytometry, gel shift assay and immunoprecipitation, respectively.
RESULTS:Nuclear fragmentation and chromatin condensation were observed at 6 h after X-irradiation and gradually increased up to 12 h. These phenomena were significantly attenuated by cycloheximide. Cycloheximide also inhibited the activation of caspases and AP-1, the expression of Fas, the formation of DISC and the release of cytochrome-C, but not the activation of SAPK/JNK in X-irradiated MOLT-4 cells.
CONCLUSION:These results indicate that apoptosis of X-ray-induced MOLT-4 cells is dependent on the activation of caspases regulated by de novo protein synthesis through SAPK/JNK activation.
巻・号 78(2)
ページ 115-24
公開日 2002-2-1
DOI 10.1080/09553000110076472
PMID 11779361
MeSH Apoptosis* Arabidopsis Proteins* Blotting, Western Caspase 3 Caspase 8 Caspase 9 Caspases / metabolism Cell Nucleus / metabolism Chromatin / metabolism Cycloheximide / pharmacology Cytochrome c Group / metabolism Dose-Response Relationship, Radiation Electrophoresis, Polyacrylamide Gel Fatty Acid Desaturases / metabolism Flow Cytometry Humans Immunoblotting Leukemia / metabolism* Leukemia / pathology* MAP Kinase Kinase 4* Membrane Potentials Microscopy, Fluorescence Mitochondria / metabolism Mitogen-Activated Protein Kinase Kinases / metabolism Precipitin Tests Protein Binding Protein Biosynthesis* Signal Transduction* Time Factors Transcription Factor AP-1 / metabolism Tumor Cells, Cultured X-Rays*
IF 2.368
引用数 24
WOS 分野 NUCLEAR SCIENCE & TECHNOLOGY RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING BIOLOGY
リソース情報
ヒト・動物細胞