Schalk I, Zeng K, Wu S K, Stura E A, Matteson J, Huang M, Tandon A, Wilson I A, Balch W E
Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Nature. 1996 May 2;381(6577):42-8. doi: 10.1038/381042a0.
The crystal structure of the bovine alpha-isoform of Rab GDP-dissociation inhibitor (GDI), which functions in vesicle-membrane transport to recycle and regulate Rab GTPases, has been determined to a resolution of 1.81 A. GDI is constructed of two main structural units, a large complex multisheet domain I and a smaller alpha-helical domain II. The structural organization of domain I is surprisingly closely related to FAD-containing monooxygenases and oxidases. Sequence-conserved regions common to GDI and the choroideraemia gene product, which delivers Rab to catalytic subunits of Rab geranylgeranyltransferase II, are clustered on one face of the molecule. The two most sequence-conserved regions, which form a compact structure at the apex of GDI, are shown by site-directed mutagenesis to play a critical role in the binding of Rab proteins.
牛源Rab GDP解离抑制剂（GDI）α异构体的晶体结构已被测定，分辨率为1.81埃。该异构体在囊泡-膜运输中发挥作用，以循环利用并调节Rab GTP酶。GDI由两个主要结构单元构成，一个是大型复合多片结构域I，另一个是较小的α螺旋结构域II。结构域I的结构组织与含黄素腺嘌呤二核苷酸（FAD）的单加氧酶和氧化酶惊人地密切相关。GDI与脉络膜血色素基因产物共有的序列保守区域，可将Rab递送至Rab geranylgeranyltransferase II的催化亚基，这些区域聚集在分子的一个面上。两个序列最保守的区域在GDI的顶端形成紧密结构，定点诱变显示它们在Rab蛋白的结合中起关键作用。
