title: Identification of ERAD components essential for dislocation of the null Hong Kong variant of α-1-antitrypsin (NHK).
abstract: Misfolded proteins or orphan subunits of protein complexes are removed from the endoplasmic reticulum (ER) by ER-associated degradation (ERAD). ERAD requires dislocation, also known as retrotranslocation, of those unwanted proteins from the ER lumen to the cytosol for destruction by the proteasomes. Over one hundred ERAD component proteins have been identified but their role in dislocation remain poorly understood. Here we assessed the requirement of ERAD components for dislocation of NHK in live cells using our recently developed dislocation-induced reconstituted GFP (drGFP) assay. RNAi revealed that 12 out of 21 ERAD components examined are required for efficient dislocation of NHK among which Hrd1, Sel1L, GRP94 and p97/VCP are critically required. In addition, knockdown of 7 of the 21 components enhanced NHK dislocation. This study uncovers a complex functional network of proteins required for NHK dislocation.
authors: Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA. Electronic address: yzhong@umaryland.edu.
authors: Yongwang
authors: Y
authors: Zhong
authors: Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
authors: Hang
authors: H
authors: Shen
authors: Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
authors: Ye
authors: Y
authors: Wang
authors: Department of Colorectal Cancer and Center for Medical Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 20025, China.
authors: Yili
authors: Y
authors: Yang
authors: Department of Obstetrics, Gynecology & Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
authors: Peixin
authors: P
authors: Yang
authors: Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA. Electronic address: sfang@umaryland.edu.
authors: Shengyun
authors: S
authors: Fang
mesh_terms: D004721:Endoplasmic Reticulum / Q000378:metabolism*; D060746:Endoplasmic Reticulum-Associated Degradation / Q000502:physiology*; D006367:HeLa Cells; D006723:Hong Kong; D006801:Humans; D000515:alpha 1-Antitrypsin / Q000378:metabolism*
chemical_list: C043392:SERPINA1 protein, human; D000515:alpha 1-Antitrypsin
keywords: Dislocation/retrotranslocation; ERAD; Hrd1; Sel1L; drGFP; p97/VCP