Functional investigations of the human voltage-dependent anion channel 1 by solid-state NMR spectroscopy

膜蛋白可以通过双层小叶为各种配体提供途径，而且通常是以可切换的方式进行的。代谢产物通过线粒体外膜(MOM)运输对于满足活细胞的能量需求是必不可少的。电压依赖性阴离子通道(VDAC)是MOM中含量最丰富的蛋白质，被认为是线粒体和细胞质之间代谢物运输的主要途径。283个残基的hVDAC1已成为决定线粒体继发细胞凋亡开始的潜在开关。因此，对门控机制的了解应该为开发具有促凋亡活性和潜在的抗肿瘤药物的小分子提供一个靶点。本项目的主要研究目标是研究hVDAC1在其自然环境中的结构和功能，即脂双层，在那里它是折叠的，在广泛的pH范围内稳定，并且已知具有通道活性。为了实现这些目标，计划进行大量的固体核磁共振波谱实验，包括2D同核和异核相关谱以及3D指配实验。将使用最先进的质子探测来进一步改善结构和功能信息。除了VDAC的开放构象和闭合构象外，VDAC还计划与小配体(ATP/NADH)以及生物大分子(如己糖激酶)相互作用。

Membrane proteins can provide pathways through a bilayer leaflet for a variety of ligands and often do so in a switchable fashion. Metabolite transport across the mitochondrial outer membrane (MOM) is essential for fulfilling the energy requirements of living cells. The voltage-dependent anion channel (VDAC) is the most abundant protein of the MOM and is known to be the primary avenue for metabolite traffic between the mitochondrion and cytoplasm. The 283-residue hVDAC1 has emerged as a potential switch determining the onset of mitochondria-relayed apoptosis. Thus, knowledge of the gating mechanism should provide a target for development of small molecules that have pro-apoptotic activity and potential as antitumor agents.The main research objective of this project is the structural and functional study of hVDAC1 in its natural environment, i.e. lipid bilayers, where it is folded, stable over wide pH range, and is known to exhibit channel activity. In order to achieve these goals, a plethora of solid-state NMR spectroscopic experiments is planned, including 2D homo- and heteronuclear correlation spectra as well as 3D assignment experiments. State-of-the-art proton detection will be used to further improve structural and functional information. Besides the structures of VDAC in its open and closed conformation, the interaction of VDAC with small ligands (ATP/NADH) as well as biomacromolecules, such as hexokinase, is planned.