Knoblach Barbara, Keller Bernd O, Groenendyk Jody, Aldred Sandi, Zheng Jing, Lemire Bernard D, Li Liang, Michalak Marek
Canadian Institutes of Health Research Membrane Protein Research Group and the Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2H7.
Mol Cell Proteomics. 2003 Oct;2(10):1104-19. doi: 10.1074/mcp.M300053-MCP200. Epub 2003 Aug 19.
Using a proteomic analysis of the luminal environment of the endoplasmic reticulum (ER), we have identified 141 proteins, of which 6 were previously unknown. Two newly discovered ER luminal proteins, designated ERp19 and ERp46, are related to protein disulphide isomerase. Western and Northern blot analyses revealed that both ERp19 and ERp46 and their respective mRNAs are highly expressed in the liver as compared with other tissues. Both proteins were enriched in purified liver ER vesicles and were localized specifically to the ER in McA-RH7777 hepatocytes. Functional analysis with yeast complementation studies showed that ERp46 but not ERp19 can substitute for protein disulphide isomerase function in vivo.
通过对内质网（ER）腔环境进行蛋白质组学分析，我们鉴定出了141种蛋白质，其中6种此前未知。两种新发现的ER腔蛋白，命名为ERp19和ERp46，与蛋白质二硫键异构酶相关。蛋白质免疫印迹法（Western blot）和RNA印迹法（Northern blot）分析显示，与其他组织相比，ERp19和ERp46及其各自的mRNA在肝脏中均高表达。这两种蛋白质在纯化的肝脏ER囊泡中富集，并在McA-RH7777肝细胞中特异性定位于内质网。酵母互补研究的功能分析表明，ERp46而非ERp19可以在体内替代蛋白质二硫键异构酶的功能。
