TPC蛋白质是内和溶酶体内酸激活的选择性离子通道
Xiang Wang1, Xiaoli Zhang, Xian-Ping Dong
1Department of Molecular, Cellular, and Developmental Biology, University of Michigan, 3089 Kraus Natural Science Building, 830 North University Avenue, Ann Arbor, MI 48109, USA.
Cell
|October 16, 2012
概括
哺乳动物的双孔通道 (TPC) 是选择性,而不是选择性,并被PI{3,5) P{2}激活,而不是NAADP. 这一发现重新定义了TPCs在调节内溶酶体功能和离子运输中的作用.
科学领域:
- 细胞生物学 细胞生物学
- 离子通道生理学 离子通道生理学
- 分子神经科学 分子神经科学
背景情况:
- 哺乳动物的双孔通道蛋白 (TPC1,TPCN1,TPC2,TPCN2) 位于内分体和溶解体中.
- 以前人们认为它们可以调解尼古丁酸腺因二核酸 (NAADP) 触发的释放.
研究的目的:
- 直接研究哺乳动物双孔通道 (TPC) 的离子选择性和封闭机制.
- 为了澄清内体中运输的初级离子和TPCs在有机细胞功能中的作用.
主要方法:
- 在内分泌体中对TPC的直接电生理记录.
- 实验使用了野生类型和TPC双击的小鼠模型.
主要成果:
- 发现TPC是选择的道,而不是选择的道.
- TPCs的激活取决于PI{3,5) P{2},并且独立于NAADP.
- (Na+) 被确定为内酶体中的主要离子,挑战了对 (K+) 的普遍假设.
结论:
- 哺乳动物TPC的功能是通过PI{3,5) P{2}调节的选择性通道.
- 这些发现修订了我们对内溶体离子运输和膜电位调节的理解.
- 这些结果为了解PI{3,5) P{2) 在有机细胞融合中的作用提供了新的基础.
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