Vps9p的CUE结构域识别泛素的机制。

Mechanism of ubiquitin recognition by the CUE domain of Vps9p.

作者信息

Prag Gali, Misra Saurav, Jones Eudora A, Ghirlando Rodolfo, Davies Brian A, Horazdovsky Bruce F, Hurley James H

机构信息

Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA.

出版信息

Cell. 2003 May 30;113(5):609-20. doi: 10.1016/s0092-8674(03)00364-7.

DOI:10.1016/s0092-8674(03)00364-7

PMID:12787502

Abstract

Coupling of ubiquitin conjugation to ER degradation (CUE) domains are approximately 50 amino acid monoubiquitin binding motifs found in proteins of trafficking and ubiquitination pathways. The 2.3 A structure of the Vps9p-CUE domain is a dimeric domain-swapped variant of the ubiquitin binding UBA domain. The 1.7 A structure of the CUE:ubiquitin complex shows that one CUE dimer binds one ubiquitin molecule. The bound CUE dimer is kinked relative to the unbound CUE dimer and wraps around ubiquitin. The CUE monomer contains two ubiquitin binding surfaces on opposite faces of the molecule that cannot bind simultaneously to a single ubiquitin molecule. Dimerization of the CUE domain allows both surfaces to contact a single ubiquitin molecule, providing a mechanism for high-affinity binding to monoubiquitin.

摘要

泛素缀合与内质网降解偶联（CUE）结构域是在运输和泛素化途径的蛋白质中发现的约50个氨基酸的单泛素结合基序。Vps9p-CUE结构域的2.3埃结构是泛素结合UBA结构域的二聚体结构域交换变体。CUE：泛素复合物的1.7埃结构表明，一个CUE二聚体结合一个泛素分子。结合的CUE二聚体相对于未结合的CUE二聚体发生弯曲，并围绕泛素缠绕。CUE单体在分子的相对面上包含两个泛素结合表面，它们不能同时与单个泛素分子结合。CUE结构域的二聚化使得两个表面都能接触单个泛素分子，为与单泛素的高亲和力结合提供了一种机制。