形成离子透通道的瘤缩因子-α
B L Kagan1, R L Baldwin, D Munoz
1Department of Psychiatry, School of Medicine, University of California, Los Angeles 90024.
概括
瘤亡因子-α (TNF) 可能通过形成离子通道来发挥其作用. 酸化会诱导形状变化,使TNF能够在脂质双层中形成pH依赖的通道,并增加细胞离子的透性.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 免疫学 免疫学 免疫学
背景情况:
- 瘤亡因子-α (TNF) 是一种参与炎症和疾病状态的蛋白质.
- 对于TNF的细胞毒性和荷尔蒙作用的确切机制尚未完全理解.
- 结构分析表明TNF剪切剂具有类似孔隙的区域,暗示了通道活动.
研究的目的:
- 调查TNF的潜在离子通道形成活性.
- 在脂质环境中探索TNF的结构和功能性质.
- 为了确定TNF的生理效应是否通过离子通道形成进行介导.
主要方法:
- 在酸化后对TNF的形态变化分析.
- 脂质囊泡插入试验. 脂质囊泡插入试验.
- 平面脂质双层电生理学,以评估离子透性.
- 在U937淋巴瘤细胞中测量透率.
主要成果:
- 酸化诱导了TNF的构造变化,增加了表面水性和膜插入.
- 在人造脂质双层中,TNF形成了依赖pH值和依赖电压的离子透通道.
- 在人类U937细胞中,TNF增加了离子透性.
结论:
- TNF具有内在的离子通道形成活性.
- 这种活动受到pH值和电压的影响.
- TNF的生理效应可能部分由其离子通道功能介导.
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