tBid forms a pore in the liposome membrane
tBid forms a pore in the liposome membrane
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DOI：
10.1016/s0014-5793(03)01346-2
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发表时间：
2003-12-18
期刊：
影响因子：
3.5
通讯作者：
Yang, FY
中科院分区：
文献类型：
--
作者：
Yan, L;Miao, Q;Yang, FY
我们研究了tBid（Bid的截短形式）结合和透化脂质体（大单层囊泡，LUV）并从LUV释放各种分子直径（FD-20、FD-70、FD-250 S）的荧光标记分子（荧光素-异硫氰酸酯-缀合葡聚糖，FITC-葡聚糖）的能力。获得的数据表明，tBid在促进FITC-葡聚糖从由心磷脂和二油酰磷脂酰胆碱（DOPC）组成的LUV中渗漏方面比由二油酰磷脂酸或二油酰磷脂酰甘油和DOPC制成的LUV更有效。渗漏效率随二油酰磷脂酰乙醇胺或二油酰磷脂酰乙醇胺用量的增加而降低。磷脂单分子层测定和荧光猝灭测量表明，tBid深深插入到酸性磷脂的疏水酰基链。考虑到TBID的三维结构，我们建议TBID可以渗透到膜的疏水核心，导致截留内容物从LUVs通过成孔机制泄漏。(C)2003年由Elsevier B. V.代表欧洲生物化学学会联合会出版。
We investigated the ability of tBid (truncated form of Bid) to bind and permeabilize the liposomes (large unilamellar vesicles, LUVs) and release fluorescent marker molecules (fluorescein-isothiocyanate-conjugated dextrans, FITC-dextrans) of various molecular diameters (FD-20, FD-70, FD-250S) from LUVs. Obtained data showed that tBid was more efficient in promoting leakage of FITC-dextrans from LUVs composed of cardiolipin and dioleoylphosphatidylcholine (DOPC) than LUVs made of dioleoylphosphatidic acid or dioleoylphosphatidylglycerol and DOPC. The leakage efficiency was reduced with increasing amount of dioleoylphosphatidylethanolamine or dielaidoylphosphatidylethanolamine. Phospholipid monolayer assay and fluorescence quenching measurements revealed that tBid inserted deeply into the hydrophobic acyl chain of acidic phospholipids. Taking into account the tBid three-dimensional structure, we propose that tBid could penetrate into the hydrophobic core of membrane, resulting in the leakage of entrapped content from LUVs via a pore-forming mechanism. (C) 2003 Published by Elsevier B.V. on behalf of the Federation of European Biochemical Societies.