Kobe B, Deisenhofer J
Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas 75235-9050.
Nature. 1995 Mar 9;374(6518):183-6. doi: 10.1038/374183a0.
The leucine-rich repeat is a recently characterized structural motif used in molecular recognition processes as diverse as signal transduction, cell adhesion, cell development, DNA repair and RNA processing. We present here the crystal structure at 2.5 A resolution of the complex between ribonuclease A and ribonuclease inhibitor, a protein built entirely of leucine-rich repeats. The unusual non-globular structure of ribonuclease inhibitor, its solvent-exposed parallel beta-sheet and the conformational flexibility of the structure are used in the interaction; they appear to be the principal reasons for the effectiveness of leucine-rich repeats as protein-binding motifs. The structure can serve as a model for the interactions of other proteins containing leucine-rich repeats with their ligands.
富含亮氨酸的重复序列是一种最近才被鉴定出的结构基序，用于分子识别过程，这些过程包括信号转导、细胞黏附、细胞发育、DNA修复和RNA加工等多种类型。我们在此展示了核糖核酸酶A与核糖核酸酶抑制剂复合物的晶体结构，分辨率为2.5埃，核糖核酸酶抑制剂是一种完全由富含亮氨酸的重复序列构成的蛋白质。核糖核酸酶抑制剂不同寻常的非球状结构、其暴露于溶剂中的平行β折叠以及结构的构象灵活性都被用于相互作用中；它们似乎是富含亮氨酸的重复序列作为蛋白质结合基序有效性的主要原因。该结构可以作为其他含有富含亮氨酸重复序列的蛋白质与其配体相互作用的模型。
