摘要:
β淀粉样蛋白(Aβ)与细胞膜相互作用形成寡聚体存在于膜脂内, 聚丙烯酰胺凝胶电泳常用于分析这些膜内寡聚体的结构和状态, 但十二烷基硫酸钠(SDS)使得寡聚体原有的结构极易被破坏, 使用合适的交联剂来稳定蛋白在膜上的状态, 从而获取寡聚体本身的结构. 用双琥珀酰亚胺辛二酸酯磺酸钠盐(BS3)对Aβ42进行交联, 将BS3与戊二醛交联进行比较分析, 通过电泳、 脂质体技术, 并采用电镜照片对照分析. 实验结果显示: 1)BS3交联后的样品能保持蛋白原先的状态;2)BS3不会导致蛋白过度交联, 很适合作为分析膜脂与β淀粉样蛋白相互作用的交联剂. 因此, 报道了BS3分析β淀粉样蛋白这种易聚集蛋白在插膜后的结构, 且BS3可以替代戊二醛成为更有效的交联剂, 这将为β淀粉样蛋白及其他易聚集蛋白插膜提供很好的研究方法.
Abstract:
Electrophoresis is often used to analyze the structure and state of Aβ oligomers which bind and adsorb with membrane.However, due to the presence of denaturing SDS, oligomers are easily broken during electrophoresis, which makes it very hard to get true Aβ aggregate states.So cross-linking was used to steady the structure state.In this paper, bis(sulfosuccinimidyl) (BS3) is used to cross-link Aβ42 oligomers before electrophoresis.These result compared with a previously reported Aβ crosslinking agent glutaraldehyde.Electron microscopy and liposome were used to observe the crosslinking results.It is quite apparent that BS3 is more sensitive in detecting intra-membrane Aβ oligomers and extra-membrane Aβ oligomers states.BS3 crosslinking with Aβ which would provide an efficient method to analyze Aβ protein and other easily aggregated proteins in vivo and in vitro studies.