Colombini Marco
Department of Biology, University of Maryland, College Park, MD 20742, USA.
Trends Biochem Sci. 2009 Aug;34(8):382-9. doi: 10.1016/j.tibs.2009.05.001. Epub 2009 Jul 31.
The recently published 3D structures of the mitochondrial voltage-dependent anion-selective channel (VDAC) are almost identical to each other. However, they are in conflict with the results of biochemical and functional studies published in the past 18 years. Transmembrane folding patterns based on many biochemical and functional studies differ from the 3D structures in the exclusion of distinct transmembrane strands. These differences might be the consequence of changes observed in vitro that result in the formation of channels with the characteristic functional properties of VDAC. Is it possible to reconcile the discrepancies between the 3D structures and earlier models? As it was refolded from inclusion bodies, the protein used to obtain the 3D structures might not be in the native conformation. Here, I propose structural rearrangements that could occur spontaneously as a possible path to convert the 3D structure to my preferred biochemically determined native structure.
最近发表的线粒体电压依赖性阴离子选择性通道(VDAC)的三维结构几乎完全相同。然而,它们与过去18年发表的生化和功能研究结果相冲突。基于许多生化和功能研究的跨膜折叠模式与三维结构不同,排除了不同的跨膜链。这些差异可能是体外观察到的变化的结果,这些变化导致形成具有VDAC特征性功能特性的通道。是否有可能调和三维结构与早期模型之间的差异?由于用于获得三维结构的蛋白质是从包涵体中重新折叠的,它可能不是天然构象。在这里,我提出了可能自发发生的结构重排,作为将三维结构转化为我更喜欢的通过生化方法确定的天然结构的一种可能途径。