Exploring the conformational dynamics of the bovine ADP/ATP carrier in mitochondria.
Exploring the conformational dynamics of the bovine ADP/ATP carrier in mitochondria.
复制标题
探索牛 ADP/ATP 载体在线粒体中的构象动力学。
作者：
Martial Rey;E. Forest;L. Pelosi
线粒体ADP/ATP载体通过在两种不同构象之间转换，催化ADP和ATP在线粒体内膜上的运输。它们可以被两种抑制剂阻断：carboxyatractyloside （CATR）和bongkrekic acid （BA）。我们对ADP/ATP转运过程的理解很大程度上是基于对个体抑制状态之间结构差异的分析。测定了牛ADP/ATP载体异构体1 （bAnc1p）与CATR配合物的x射线晶体三维结构，但ba -载体配合物的结构尚不清楚。我们最近利用氢/氘交换和质谱（HDX-MS）研究了bAnc1p在洗涤剂溶液中的构象动力学。这项研究揭示了ADP/ATP易位的一些特征，但其机制本身和bAnc1p在膜中的组织还有待进一步研究。本文首次利用HDX-MS在全蛋白水平上对线粒体中的bAnc1p进行了研究。膜包埋的bAnc1p在hdx - ms兼容的条件下氘化和纯化。我们的结果在线粒体内膜载体不同于那些发表的载体在洗涤剂溶液。这些差异主要在空腔的上半部分，无论分析何种配合物，总的来说都显示出有限的H/D交换，并且在基质环的水平上，ba -载体配合物中的溶剂比catr -载体配合物中的溶剂更难接近。它们与已发表的关于bAnc1p的数据进行了讨论，并为线粒体中与BA复合物的牛载体的基质环的构象提供了新的见解。
The mitochondrial ADP/ATP carrier catalyzes the transport of ADP and ATP across the mitochondrial inner membrane by switching between two different conformations. They can be blocked by two inhibitors: carboxyatractyloside (CATR) and bongkrekic acid (BA). Our understanding of the ADP/ATP transport process is largely based on analysis of structural differences between the individual inhibited states. The X-ray crystallographic three-dimensional structure of bovine ADP/ATP carrier isoform 1 (bAnc1p) complexed with CATR was determined, but the structure of the BA-carrier complex remains unknown. We recently investigated the conformational dynamics of bAnc1p in detergent solution using hydrogen/deuterium exchange and mass spectrometry (HDX-MS). This study shed light on some features of ADP/ATP translocation, but the mechanism itself and the organization of bAnc1p in the membrane required further investigation. This paper describes the first study of bAnc1p in the mitochondria on the whole-protein scale using HDX-MS. Membrane-embedded bAnc1p was deuterated and purified under HDX-MS-compatible conditions. Our results for the carrier in the mitochondrial inner membrane differed from those published for the carrier in a detergent solution. These differences were mainly in the upper half of the cavity that globally showed a limited H/D exchange whatever the complex analyzed and at the level of the matrix loops that were less accessible to the solvent in the BA-carrier complex than in the CATR-carrier complex. They are discussed with respect to published data for bAnc1p and have provided new insights into the conformation of the matrix loops of the bovine carrier in complex with BA in mitochondria.
影响因子：
13.8
作者：
Hiller, Sebastian;Abramson, Jeff;Mannella, Carmen;Wagner, Gerhard;Zeth, Kornelius
通讯作者：
Zeth, Kornelius