Interaction between the Linker, Pre-S1, and TRP Domains Determines Folding, Assembly, and Trafficking of TRPV Channels
Interaction between the Linker, Pre-S1, and TRP Domains Determines Folding, Assembly, and Trafficking of TRPV Channels
复制标题
DOI：
10.1016/j.str.2015.05.018
复制
发表时间：
2015-08-04
期刊：
影响因子：
5.7
通讯作者：
Valverde, Miguel A.
中科院分区：
文献类型：
--
作者：
Garcia-Elias, Anna;Berna-Erro, Alejandro;Valverde, Miguel A.
功能性瞬时受体电位(Trp)通道由四个亚基组装而成。在这里，我们展示了前-S1、Trp与TRPV1和TRPV4的Ankyrin Repeat结构域(ARD)-S1连接器域之间的相互作用，这对于正确的通道组装是必不可少的。中和TRPV4前-S1 K462导致内质网蛋白滞留，糖基化和转运缺陷，对TRPV4激活刺激无反应。TRPV1Pre-S1的等值突变也得到了类似的结果。分子动力学模拟表明，TRPV4-K462与E745(Trp盒)和D425(Pre-S1接头)形成交替的氢网络，K462Q突变影响亚基折叠。单一的TRPV4-E745A或TRPV4-D425A突变对TRPV4的生物发生有中度影响，而双突变的TRPV4-D425A/E745A恢复了TRPV4-K462Q的表型。因此，前-S1、Trp和连接器域之间的相互作用对于产生结构构象是必需的，该结构构象允许相邻亚基之间的接触促进正确的组装和运输到质膜。
Functional transient receptor potential (TRP) channels result from the assembly of four subunits. Here, we show an interaction between the pre-S1, TRP, and the ankyrin repeat domain (ARD)-S1 linker domains of TRPV1 and TRPV4 that is essential for proper channel assembly. Neutralization of TRPV4 pre-S1 K462 resulted in protein retention in the ER, defective glycosylation and trafficking, and unresponsiveness to TRPV4-activating stimuli. Similar results were obtained with the equivalent mutation in TRPV1 pre-S1. Molecular dynamics simulations revealed that TRPV4-K462 generated an alternating hydrogen network with E745 (TRP box) and D425 (pre-S1 linker), and that K462Q mutation affected subunit folding. Consistently, single TRPV4-E745A or TRPV4-D425A mutations moderately affected TRPV4 biogenesis while double TRPV4-D425A/E745A mutation resumed the TRPV4-K462Q phenotype. Thus, the interaction between pre-S1, TRP, and linker domains is mandatory to generate a structural conformation that allows the contacts between adjacent subunits to promote correct assembly and trafficking to the plasma membrane.