文献类型：期刊文献

英文题名：The substrate binding domains of human SIAH E3 ubiquitin ligases are now crystal clear

作者：Zhang, Qi[1];Wang, Zhongduo[2];Hou, Feng[1];Harding, Rachel[1];Huang, Xinyi[3];Dong, Aiping[1];Walker, John R.[1];Tong, Yufeng[1,3]

机构：[1]Univ Toronto, Struct Genom Consortium, Toronto, ON M5G 1L7, Canada;[2]Guangdong Ocean Univ, Coll Fisheries, Zhanjiang 524025, Guangdong, Peoples R China;[3]Univ Toronto, Dept Pharmacol & Toxicol, Toronto, ON M5G 1L7, Canada

年份：2017

卷号：1861

期号：1

起止页码：3095

外文期刊名：BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS

收录：SCI-EXPANDED(收录号：WOS:000390736300019)、、Scopus(收录号：2-s2.0-84994342350)、WOS

基金：The Structural Genomics Consortium (SGC) is a registered charity (number 1097737) that receives funds from AbbVie, Bayer Pharma AG, Boehringer Ingelheim, Canada Foundation for Innovation, Eshelman Institute for Innovation, Genome Canada through Ontario Genomics Institute, Innovative Medicines Initiative (EU/EFPIA) [ULTRA-DD grant no. 115766], Janssen, Merck & Co., Novartis Pharma AG, Ontario Ministry of Economic Development and Innovation, Pfizer, Sao Paulo Research Foundation-FAPESP, Takeda, and the Wellcome Trust. X-ray diffraction data were collected at Argonne National Laboratory, Structural Biology Center at the Advanced Photon Source, which is operated by UChicago Argonne, LLC, for the U.S. Department of Energy, Office of Biological and Environmental Research under contract DE-AC02-06CH11357. Z.W is a visiting scholar at the SGC sponsored by the National Natural Science Foundation of China (31201996), and Excellent Young Teachers Program of Guangdong Province (Yq2013091 and Yq2013089). We are grateful for Guillermo Senisterra and Albina Bolotokova for technical support.

语种：英文

外文关键词：Crystallography; Deubiquitinase; E3 Ubiquitin ligase; Menadione; Small molecule inhibitors; Protein-protein interaction

外文摘要：Background: Seven in absentia homologs (SIAHs) comprise a family of highly conserved E3 ubiquitin ligases that play an important role in regulating signalling pathways in tumorigenesis, including the DNA damage repair and hypoxia response pathways. SIAH1 and SIAH2 have been found to function as a tumour repressor and a protooncogene, respectively, despite the high sequence identity of their substrate binding domains (SBDs). Ubiquitin-specific protease USP19 is a deubiquitinase that forms a complex with SIAHs and counteracts the ligase function. Much effort has been made to find selective inhibitors of the SIAHs E3 ligases. Menadione was reported to inhibit SIAH2 specifically. Methods: We used X-ray crystallography, peptide array, bioinformatic analysis, and biophysical techniques to characterize the structure and interaction of SIAHs with deubiquitinases and literature reported compounds. Results: We solved the crystal structures of SIAH1 in complex with a USP19 peptide and of the apo form SIAH2. Phylogenetic analysis revealed the SIAH/USP19 complex is conserved in evolution. We demonstrated that menadione destabilizes both SIAH1 and SIAH2 non-specifically through covalent modification. Conclusions: The SBDs of SIAH E3 ligases are structurally similar with a subtle stability difference. USP19 is the only deubiquitinase that directly binds to SIAHs through the substrate binding pocket. Menadione is not a specific inhibitor for SIAH2. General significance: The crystallographic models provide structural insights into the substrate binding of the SIAH family E3 ubiquitin ligases that are critically involved in regulating cancer-related pathways. Our results suggest caution should be taken when using menadione as a specific SIAH2 inhibitor. (C) 2016 Elsevier B.V. All rights reserved.