title: BimL involvement in Bax activation during UV irradiation-induced apoptosis.
abstract: Bax, a proapoptotic member of the Bcl-2 family, localizes largely in the cytoplasm but translocates to mitochondria and undergoes oligomerization to induce the release of apoptogenic factors in response to apoptotic stimuli. However, the molecular mechanism of Bax activation is not fully understood. We show here the role of BimL in Bax activation during UV irradiation-induced apoptosis. In this study, GFP-BimL plasmid was constructed. The dynamic interaction between BimL and Bax during UV irradiation-induced apoptosis was observed using fluorescence resonance energy transfer (FRET) technique. Our experimental results showed that BimL translocation to mitochondria occurred before Bax translocation, and that BimL activated Bax indirectly. Moreover, inhibition of c-Jun N-terminal protein kinase (JNK) activation blocked BimL translocation, delayed and attenuated Bax translocation and subsequent apoptosis. These results demonstrate that BimL is involved in UV irradiation-induced apoptosis by indirectly activating Bax.
authors.affiliation: MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, South China Normal University, Guangzhou, China.
authors.forename: Miaojuan
authors.initials: M
authors.lastname: Chen
authors.forename: Da
authors.initials: D
authors.lastname: Xing
authors.forename: Tongsheng
authors.initials: T
authors.lastname: Chen
authors.forename: Lan
authors.initials: L
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis / Q000528:radiation effects*; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D000072224:Bcl-2-Like Protein 11; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D045744:Cell Line, Tumor; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D011829:Radiation Dosage; D015398:Signal Transduction / Q000528:radiation effects; D014466:Ultraviolet Rays; D051028:bcl-2-Associated X Protein / Q000378:metabolism*
chemical_list: D051017:Apoptosis Regulatory Proteins; C494826:BAX protein, human; C000606775:BCL2L11 protein, human; D000072224:Bcl-2-Like Protein 11; D008565:Membrane Proteins; D011518:Proto-Oncogene Proteins; D051028:bcl-2-Associated X Protein