细胞凋亡过程中Bid蛋白在活细胞内的动态分布

Dynamics of Distribution of Bid Protein during TNF-α-induced Apoptosis in Living Cell

当细胞暴露于凋亡诱导因子如肿瘤坏死因子(tumornecrosisfactor-α,TNF-α)等的环境中,被激活的凋亡酶Caspase8将Bid蛋白切割成两个片断,随后其C-端片段转移到线粒体上诱发细胞色素c的释放,最终引起细胞凋亡。虽然关于Bid蛋白的研究已经取得了很大进展,但是Bid蛋白是如何转移到线粒体以及如何引起细胞色素c释放等许多问题尚未十分明了。为了进一步对Bid蛋白的生物学行为进行研究,特别是在无损伤、活细胞生理条件下,本实验采用了荧光蛋白标记和荧光成像技术对凋亡过程中Bid蛋白在活细胞内分布的动态过程进行了初步研究。

When human lung cancer cells are exposed to death-inducing molecules such as tumor necrosis factor-α, TNF-α）, caspase8 is activated and cleaves Bid into two fragments, then the C-terminal fragment relocates from cytosol to mitochondria and promotes the release of cytochrome c, finally cellular apoptosis is induced. Despite recent progress in the study of Bid during apoptosis induction, it remains unclear how C-terminal fragment of Bid cleaved moves to mitechondria and then induces the release of cytochrome c and other substances. In order to further study the biological action of Bid during apoptosis, especially under physiological condition of living cell, the distribution of Bid in individual living cell during the apoptosis was primarily investigated by the use of fluorescence microscopy.