Pore formation by a bax-derived peptide:: Effect on the line tension of the membrane probed by AFM
Pore formation by a bax-derived peptide:: Effect on the line tension of the membrane probed by AFM
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DOI：
10.1529/biophysj.106.100370
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发表时间：
2007-07-01
影响因子：
3.4
通讯作者：
Schwille, Petra
中科院分区：
文献类型：
--
作者：
Garcia-Saez, Ana J.;Chiantia, Salvatore;Schwille, Petra
Bax 是生理性细胞死亡的关键调节因子，可增加线粒体外膜的通透性，并促进细胞凋亡过程中所谓的凋亡因子的释放。作用的分子机制尚不清楚，但可能涉及 Bax 诱导的部分脂质孔的形成。为了研究 Bax 与脂质膜的相互作用以及 Bax 孔形成背后的物理变化，我们使用了源自该蛋白质螺旋 5 (Bax-alpha 5) 的活性肽，它能够在脂质双层中诱导 Bax 样孔。我们报告了由于相分离脂质双层中的域界面处和原子力显微镜中的孔边缘处的肽结合而导致的线张力降低。 lm-断裂实验。这种线张力的降低可能是成孔肽和蛋白质的一般策略，因为它影响孔的能量并稳定开放状态。
Bax is a critical regulator of physiological cell death that increases the permeability of the outer mitochondrial membrane and facilitates the release of the so-called apoptotic factors during apoptosis. The molecular mechanism of action is unknown, but it probably involves the formation of partially lipidic pores induced by Bax. To investigate the interaction of Bax with lipid membranes and the physical changes underlying the formation of Bax pores, we used an active peptide derived from helix 5 of this protein (Bax-alpha 5) that is able to induce Bax-like pores in lipid bilayers. We report the decrease of line tension due to peptide binding both at the domain interface in phase-separated lipid bilayers and at the pore edge in atomic force microscopy. lm-rupture experiments. Such a decrease in line tension may be a general strategy of pore-forming peptides and proteins, as it affects the energetics of the pore and stabilizes the open state.