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Nguyen NH, Brodsky JL. The cellular pathways that maintain the quality control and transport of diverse potassium channels. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2023; 1866:194908. [PMID: 36638864 PMCID: PMC9908860 DOI: 10.1016/j.bbagrm.2023.194908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/20/2022] [Accepted: 01/03/2023] [Indexed: 01/12/2023]
Abstract
Potassium channels are multi-subunit transmembrane proteins that permit the selective passage of potassium and play fundamental roles in physiological processes, such as action potentials in the nervous system and organismal salt and water homeostasis, which is mediated by the kidney. Like all ion channels, newly translated potassium channels enter the endoplasmic reticulum (ER) and undergo the error-prone process of acquiring post-translational modifications, folding into their native conformations, assembling with other subunits, and trafficking through the secretory pathway to reach their final destinations, most commonly the plasma membrane. Disruptions in these processes can result in detrimental consequences, including various human diseases. Thus, multiple quality control checkpoints evolved to guide potassium channels through the secretory pathway and clear potentially toxic, aggregation-prone misfolded species. We will summarize current knowledge on the mechanisms underlying potassium channel quality control in the secretory pathway, highlight diseases associated with channel misfolding, and suggest potential therapeutic routes.
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Affiliation(s)
- Nga H Nguyen
- Department of Biological Sciences, University of Pittsburgh, A320 Langley Hall, Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260, USA
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, A320 Langley Hall, Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260, USA.
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2
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Yang HQ, Echeverry FA, ElSheikh A, Gando I, Anez Arredondo S, Samper N, Cardozo T, Delmar M, Shyng SL, Coetzee WA. Subcellular trafficking and endocytic recycling of K ATP channels. Am J Physiol Cell Physiol 2022; 322:C1230-C1247. [PMID: 35508187 PMCID: PMC9169827 DOI: 10.1152/ajpcell.00099.2022] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 04/27/2022] [Accepted: 04/30/2022] [Indexed: 11/22/2022]
Abstract
Sarcolemmal/plasmalemmal ATP-sensitive K+ (KATP) channels have key roles in many cell types and tissues. Hundreds of studies have described how the KATP channel activity and ATP sensitivity can be regulated by changes in the cellular metabolic state, by receptor signaling pathways and by pharmacological interventions. These alterations in channel activity directly translate to alterations in cell or tissue function, that can range from modulating secretory responses, such as insulin release from pancreatic β-cells or neurotransmitters from neurons, to modulating contractile behavior of smooth muscle or cardiac cells to elicit alterations in blood flow or cardiac contractility. It is increasingly becoming apparent, however, that KATP channels are regulated beyond changes in their activity. Recent studies have highlighted that KATP channel surface expression is a tightly regulated process with similar implications in health and disease. The surface expression of KATP channels is finely balanced by several trafficking steps including synthesis, assembly, anterograde trafficking, membrane anchoring, endocytosis, endocytic recycling, and degradation. This review aims to summarize the physiological and pathophysiological implications of KATP channel trafficking and mechanisms that regulate KATP channel trafficking. A better understanding of this topic has potential to identify new approaches to develop therapeutically useful drugs to treat KATP channel-related diseases.
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Affiliation(s)
- Hua-Qian Yang
- Cyrus Tang Hematology Center, Soochow University, Suzhou, People's Republic of China
| | | | - Assmaa ElSheikh
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon
- Department of Medical Biochemistry, Tanta University, Tanta, Egypt
| | - Ivan Gando
- Department of Pathology, NYU School of Medicine, New York, New York
| | | | - Natalie Samper
- Department of Pathology, NYU School of Medicine, New York, New York
| | - Timothy Cardozo
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, New York
| | - Mario Delmar
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, New York
- Department of Medicine, NYU School of Medicine, New York, New York
| | - Show-Ling Shyng
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon
| | - William A Coetzee
- Department of Pathology, NYU School of Medicine, New York, New York
- Department of Neuroscience & Physiology, NYU School of Medicine, New York, New York
- Department of Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, New York
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3
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Kir Channel Molecular Physiology, Pharmacology, and Therapeutic Implications. Handb Exp Pharmacol 2021; 267:277-356. [PMID: 34345939 DOI: 10.1007/164_2021_501] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
For the past two decades several scholarly reviews have appeared on the inwardly rectifying potassium (Kir) channels. We would like to highlight two efforts in particular, which have provided comprehensive reviews of the literature up to 2010 (Hibino et al., Physiol Rev 90(1):291-366, 2010; Stanfield et al., Rev Physiol Biochem Pharmacol 145:47-179, 2002). In the past decade, great insights into the 3-D atomic resolution structures of Kir channels have begun to provide the molecular basis for their functional properties. More recently, computational studies are beginning to close the time domain gap between in silico dynamic and patch-clamp functional studies. The pharmacology of these channels has also been expanding and the dynamic structural studies provide hope that we are heading toward successful structure-based drug design for this family of K+ channels. In the present review we focus on placing the physiology and pharmacology of this K+ channel family in the context of atomic resolution structures and in providing a glimpse of the promising future of therapeutic opportunities.
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Liu Y, Wang Z, Liu H, Wang X, Zhang Z, Xiao B, An B, Zhang J. Derlin-1 functions as a growth promoter in breast cancer. Biol Chem 2020; 401:377-387. [PMID: 31721721 DOI: 10.1515/hsz-2018-0442] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 10/08/2019] [Indexed: 12/31/2022]
Abstract
Breast cancer is one of the most common malignant tumors in women. Derlin-1 has been found to be overexpressed in several human cancers in addition to playing an important role in tumor processes; however, the expression patterns and functions of Derlin-1 in human breast cancer are not fully understood. In this study, we found that Derlin-1 overexpression was higher in breast cancer compared to normal samples through TCGA and GTEx database analyses. Kaplan-Meier plotter analysis showed that Derlin-1 was a predicting factor for patient prognosis. Derlin-1 expression was significantly up-regulated in breast cancer tissues (18/30, 60.00%) compared to corresponding paracancerous tissue (9/30, 30.00%, p < 0.05) as detected by immunohistochemistry, and the expression of Derlin-1 was correlated to pathological grading. siRNA interference of Derlin-1 inhibited cell proliferation, which is associated with the promotion of apoptosis and migration. Derlin-1 knockdown suppressed the protein levels of p-AKT and Cyclin D1 while up-regulating Caspase3 and Bax. GEPIA database analysis showed that MTDH and ATAD2 were downstream target genes, and the expression of MTDH and was suppressed in Derlin-1 knockdown cells. Taken together, our results demonstrated ATAD2 that Derlin-1 is overexpressed in breast cancer and promoted a malignant phenotype through the AKT signaling pathway.
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Affiliation(s)
- Yansong Liu
- Department of Breast Surgery, Shandong Cancer Hospital, 440 Jiyan Road, Jinan 250000, Shandong, China
| | - Ziming Wang
- Department of Breast Surgery, The Second Children and Women's Healthcare of Jinan City, 12 Fengcheng West Road, Laiwu District, Jinan 271100, Shandong, China
| | - Handong Liu
- Department of Breast Surgery, Jinan Integrated Traditional Chinese and Western Medicine Hospital, 8 Wanyuan East Road, Laiwu District, Jinan 271100, Shandong, China
| | - Xin Wang
- Department of General Surgery, Yinan People's Hospital, 50 Lishan Road, Yinan 276300, Shandong, China
| | - Zhonghua Zhang
- Department of General Surgery, Dongping Country People's Hospital, Dongping, Shandong, China
| | - Bin Xiao
- Department of Breast, Shanxian Hygeia Hospital, West Lake Road, Shanxian 274300, Shandong, China
| | - Baoming An
- Department of General Surgery, Wulian People's Hospital, 50 Limin Road, Wulian 262300, Shandong, China
| | - Jun Zhang
- Department of Breast, Zhangqiu Hospital of Chinese Medicine, 1463 Mingshui Road, Zhangqiu District, Jinan 250200, Shandong, China
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Martin GM, Sung MW, Shyng SL. Pharmacological chaperones of ATP-sensitive potassium channels: Mechanistic insight from cryoEM structures. Mol Cell Endocrinol 2020; 502:110667. [PMID: 31821855 PMCID: PMC6994177 DOI: 10.1016/j.mce.2019.110667] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 11/22/2019] [Accepted: 11/22/2019] [Indexed: 02/07/2023]
Abstract
ATP-sensitive potassium (KATP) channels are uniquely evolved protein complexes that couple cell energy levels to cell excitability. They govern a wide range of physiological processes including hormone secretion, neuronal transmission, vascular dilation, and cardiac and neuronal preconditioning against ischemic injuries. In pancreatic β-cells, KATP channels composed of Kir6.2 and SUR1, encoded by KCNJ11 and ABCC8, respectively, play a key role in coupling blood glucose concentration to insulin secretion. Mutations in ABCC8 or KCNJ11 that diminish channel function result in congenital hyperinsulinism. Many of these mutations principally hamper channel biogenesis and hence trafficking to the cell surface. Several small molecules have been shown to correct channel biogenesis and trafficking defects. Here, we review studies aimed at understanding how mutations impair channel biogenesis and trafficking and how pharmacological ligands overcome channel trafficking defects, particularly highlighting recent cryo-EM structural studies which have shed light on the mechanisms of channel assembly and pharmacological chaperones.
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Affiliation(s)
- Gregory M Martin
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Min Woo Sung
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Show-Ling Shyng
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA.
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Nowakowska-Gołacka J, Sominka H, Sowa-Rogozińska N, Słomińska-Wojewódzka M. Toxins Utilize the Endoplasmic Reticulum-Associated Protein Degradation Pathway in Their Intoxication Process. Int J Mol Sci 2019; 20:E1307. [PMID: 30875878 PMCID: PMC6471375 DOI: 10.3390/ijms20061307] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 03/08/2019] [Accepted: 03/10/2019] [Indexed: 12/25/2022] Open
Abstract
Several bacterial and plant AB-toxins are delivered by retrograde vesicular transport to the endoplasmic reticulum (ER), where the enzymatically active A subunit is disassembled from the holotoxin and transported to the cytosol. In this process, toxins subvert the ER-associated degradation (ERAD) pathway. ERAD is an important part of cellular regulatory mechanism that targets misfolded proteins to the ER channels, prior to their retrotranslocation to the cytosol, ubiquitination and subsequent degradation by a protein-degrading complex, the proteasome. In this article, we present an overview of current understanding of the ERAD-dependent transport of AB-toxins to the cytosol. We describe important components of ERAD and discuss their significance for toxin transport. Toxin recognition and disassembly in the ER, transport through ER translocons and finally cytosolic events that instead of overall proteasomal degradation provide proper folding and cytotoxic activity of AB-toxins are discussed as well. We also comment on recent reports presenting medical applications for toxin transport through the ER channels.
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Affiliation(s)
- Jowita Nowakowska-Gołacka
- Department of Medical Biology and Genetics, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
| | - Hanna Sominka
- Department of Medical Biology and Genetics, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
| | - Natalia Sowa-Rogozińska
- Department of Medical Biology and Genetics, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
| | - Monika Słomińska-Wojewódzka
- Department of Medical Biology and Genetics, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland.
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Cnop M, Toivonen S, Igoillo-Esteve M, Salpea P. Endoplasmic reticulum stress and eIF2α phosphorylation: The Achilles heel of pancreatic β cells. Mol Metab 2017; 6:1024-1039. [PMID: 28951826 PMCID: PMC5605732 DOI: 10.1016/j.molmet.2017.06.001] [Citation(s) in RCA: 179] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 05/19/2017] [Accepted: 06/01/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Pancreatic β cell dysfunction and death are central in the pathogenesis of most if not all forms of diabetes. Understanding the molecular mechanisms underlying β cell failure is important to develop β cell protective approaches. SCOPE OF REVIEW Here we review the role of endoplasmic reticulum stress and dysregulated endoplasmic reticulum stress signaling in β cell failure in monogenic and polygenic forms of diabetes. There is substantial evidence for the presence of endoplasmic reticulum stress in β cells in type 1 and type 2 diabetes. Direct evidence for the importance of this stress response is provided by an increasing number of monogenic forms of diabetes. In particular, mutations in the PERK branch of the unfolded protein response provide insight into its importance for human β cell function and survival. The knowledge gained from different rodent models is reviewed. More disease- and patient-relevant models, using human induced pluripotent stem cells differentiated into β cells, will further advance our understanding of pathogenic mechanisms. Finally, we review the therapeutic modulation of endoplasmic reticulum stress and signaling in β cells. MAJOR CONCLUSIONS Pancreatic β cells are sensitive to excessive endoplasmic reticulum stress and dysregulated eIF2α phosphorylation, as indicated by transcriptome data, monogenic forms of diabetes and pharmacological studies. This should be taken into consideration when devising new therapeutic approaches for diabetes.
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Key Words
- ATF, activating transcription factor
- CHOP, C/EBP homologous protein
- CRISPR, clustered regularly interspaced short palindromic repeats
- CReP, constitutive repressor of eIF2α phosphorylation
- Diabetes
- ER, endoplasmic reticulum
- ERAD, ER-associated degradation
- Endoplasmic reticulum stress
- GCN2, general control non-derepressible-2
- GIP, glucose-dependent insulinotropic polypeptide
- GLP-1, glucagon-like peptide 1
- GWAS, genome-wide association study
- HNF1A, hepatocyte nuclear factor 1-α
- HRI, heme-regulated inhibitor kinase
- IAPP, islet amyloid polypeptide
- IER3IP1, immediate early response-3 interacting protein-1
- IRE1, inositol-requiring protein-1
- ISR, integrated stress response
- Insulin
- Islet
- MEHMO, mental retardation, epilepsy, hypogonadism and -genitalism, microcephaly and obesity
- MODY, maturity-onset diabetes of the young
- NRF2, nuclear factor, erythroid 2 like 2
- PBA, 4-phenyl butyric acid
- PERK, PKR-like ER kinase
- PKR, protein kinase RNA
- PP1, protein phosphatase 1
- PPA, phenylpropenoic acid glucoside
- Pancreatic β cell
- Pdx1, pancreatic duodenal homeobox 1
- RIDD, regulated IRE1-dependent decay
- RyR2, type 2 ryanodine receptor/Ca2+ release channel
- SERCA, sarcoendoplasmic reticulum Ca2+ ATPase
- TUDCA, taurine-conjugated ursodeoxycholic acid derivative
- UPR, unfolded protein response
- WFS, Wolfram syndrome
- XBP1, X-box binding protein 1
- eIF2, eukaryotic translation initiation factor 2
- eIF2α
- hESC, human embryonic stem cell
- hPSC, human pluripotent stem cell
- hiPSC, human induced pluripotent stem cell
- uORF, upstream open reading frame
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Affiliation(s)
- Miriam Cnop
- ULB Center for Diabetes Research, Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
- Division of Endocrinology, Erasmus Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Sanna Toivonen
- ULB Center for Diabetes Research, Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Mariana Igoillo-Esteve
- ULB Center for Diabetes Research, Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Paraskevi Salpea
- ULB Center for Diabetes Research, Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium
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Printsev I, Curiel D, Carraway KL. Membrane Protein Quantity Control at the Endoplasmic Reticulum. J Membr Biol 2017; 250:379-392. [PMID: 27743014 PMCID: PMC5392169 DOI: 10.1007/s00232-016-9931-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 09/28/2016] [Indexed: 02/07/2023]
Abstract
The canonical function of the endoplasmic reticulum-associated degradation (ERAD) system is to enforce quality control among membrane-associated proteins by targeting misfolded secreted, intra-organellar, and intramembrane proteins for degradation. However, increasing evidence suggests that ERAD additionally functions in maintaining appropriate levels of a subset of membrane-associated proteins. In this 'quantity control' capacity, ERAD responds to environmental cues to regulate the proteasomal degradation of specific ERAD substrates according to cellular need. In this review, we discuss in detail seven proteins that are targeted by the ERAD quantity control system. Not surprisingly, ERAD-mediated protein degradation is a key regulatory feature of a variety of ER-resident proteins, including HMG-CoA reductase, cytochrome P450 3A4, IP3 receptor, and type II iodothyronine deiodinase. In addition, the ERAD quantity control system plays roles in maintaining the proper stoichiometry of multi-protein complexes by mediating the degradation of components that are produced in excess of the limiting subunit. Perhaps somewhat unexpectedly, recent evidence suggests that the ERAD quantity control system also contributes to the regulation of plasma membrane-localized signaling receptors, including the ErbB3 receptor tyrosine kinase and the GABA neurotransmitter receptors. For these substrates, a proportion of the newly synthesized yet properly folded receptors are diverted for degradation at the ER, and are unable to traffic to the plasma membrane. Given that receptor abundance or concentration within the plasma membrane plays key roles in determining signaling efficiency, these observations may point to a novel mechanism for modulating receptor-mediated cellular signaling.
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Affiliation(s)
- Ignat Printsev
- Department of Biochemistry and Molecular Medicine, and UC Davis Comprehensive Cancer Center, UC Davis School of Medicine, Research Building III, Room 1100B, 4645 2nd Avenue, Sacramento, CA, 95817, USA
| | - Daniel Curiel
- Department of Biochemistry and Molecular Medicine, and UC Davis Comprehensive Cancer Center, UC Davis School of Medicine, Research Building III, Room 1100B, 4645 2nd Avenue, Sacramento, CA, 95817, USA
| | - Kermit L Carraway
- Department of Biochemistry and Molecular Medicine, and UC Davis Comprehensive Cancer Center, UC Davis School of Medicine, Research Building III, Room 1100B, 4645 2nd Avenue, Sacramento, CA, 95817, USA.
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Kim JL, La Gamma EF, Estabrook T, Kudrick N, Nankova BB. Whole genome expression profiling associates activation of unfolded protein response with impaired production and release of epinephrine after recurrent hypoglycemia. PLoS One 2017; 12:e0172789. [PMID: 28234964 PMCID: PMC5325535 DOI: 10.1371/journal.pone.0172789] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 02/09/2017] [Indexed: 12/25/2022] Open
Abstract
Recurrent hypoglycemia can occur as a major complication of insulin replacement therapy, limiting the long-term health benefits of intense glycemic control in type 1 and advanced type 2 diabetic patients. It impairs the normal counter-regulatory hormonal and behavioral responses to glucose deprivation, a phenomenon known as hypoglycemia associated autonomic failure (HAAF). The molecular mechanisms leading to defective counter-regulation are not completely understood. We hypothesized that both neuronal (excessive cholinergic signaling between the splanchnic nerve fibers and the adrenal medulla) and humoral factors contribute to the impaired epinephrine production and release in HAAF. To gain further insight into the molecular mechanism(s) mediating the blunted epinephrine responses following recurrent hypoglycemia, we utilized a global gene expression profiling approach. We characterized the transcriptomes during recurrent (defective counter-regulation model) and acute hypoglycemia (normal counter-regulation group) in the adrenal medulla of normal Sprague-Dawley rats. Based on comparison analysis of differentially expressed genes, a set of unique genes that are activated only at specific time points after recurrent hypoglycemia were revealed. A complementary bioinformatics analysis of the functional category, pathway, and integrated network indicated activation of the unfolded protein response. Furthermore, at least three additional pathways/interaction networks altered in the adrenal medulla following recurrent hypoglycemia were identified, which may contribute to the impaired epinephrine secretion in HAAF: greatly increased neuropeptide signaling (proenkephalin, neuropeptide Y, galanin); altered ion homeostasis (Na+, K+, Ca2+) and downregulation of genes involved in Ca2+-dependent exocytosis of secretory vesicles. Given the pleiotropic effects of the unfolded protein response in different organs, involved in maintaining glucose homeostasis, these findings uncover broader general mechanisms that arise following recurrent hypoglycemia which may afford clinicians an opportunity to modulate the magnitude of HAAF syndrome.
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Affiliation(s)
- Juhye Lena Kim
- The Regional Neonatal Center, Maria Fareri Children’s Hospital at Westchester Medical Center, Valhalla, New York, United States of America
| | - Edmund F. La Gamma
- The Regional Neonatal Center, Maria Fareri Children’s Hospital at Westchester Medical Center, Valhalla, New York, United States of America
- Departments of Pediatrics, Biochemistry and Molecular Biology, Division of Newborn Medicine, New York Medical College, Valhalla, New York, United States of America
| | - Todd Estabrook
- New York Medical College School of Medicine, Valhalla, New York, United States of America
| | - Necla Kudrick
- The Regional Neonatal Center, Maria Fareri Children’s Hospital at Westchester Medical Center, Valhalla, New York, United States of America
| | - Bistra B. Nankova
- Departments of Pediatrics, Biochemistry and Molecular Biology, Division of Newborn Medicine, New York Medical College, Valhalla, New York, United States of America
- * E-mail:
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Li D, Shi M, Ji H, Chen G, Jiang H, Wang Z. MicroRNA-181d is a tumor suppressor in human esophageal squamous cell carcinoma inversely regulating Derlin-1. Oncol Rep 2016; 36:2041-8. [PMID: 27572270 DOI: 10.3892/or.2016.5028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 07/25/2016] [Indexed: 11/06/2022] Open
Abstract
Esophageal squamous cell carcinoma (ESCC) is the predominant subtype of human esophageal cancer in East Asia. In the present study, we explored the tumor suppressive function of microRNA-181d (miR-181d) in ESCC. Quantitative RT-PCR was used to assess gene levels of miR‑181d in both ESCC cell lines and clinical samples. Lentiviral transduction was used to overexpress miR-181d in ECA109 and Kyse30 cells. The possible tumor suppressive effects of miR-181d overexpression on ESCC proliferation, migration and cell cycle transition in vitro, and tumorigenicity in vivo were examined. Downstream target gene of miR‑181d in ESCC, Derlin-1 (DERL1) was assessed by luciferase assay and qRT-PCR. DERL1 was also force expressed in miR‑181d-overexperssed ECA109 and Kyse30 cells to evaluate its reverse effect on miR-181d mediated tumor suppression in ESCC. miR-181d was aberrantly downregulated in both ESCC cell lines and human tumors. Lentivirus-mediated miR-181d overexpression had significant tumor suppressing functions by inhibiting cancer proliferation, migration and arresting cell cycle transition in vitro, as well as inhibiting tumorigenicity in vivo. DERL1 was identified as downstream target gene of miR-181d in ESCC cells. Forced overexpression of DERL1 in ESCC cells was shown to greatly reverse the tumor suppressive effects of miR-181d upregulation on ESCC in vitro proliferation, migration and cell cycle arrest. Out data suggest that miR-181d is a tumor suppressor in ESCC inversely regulating its downstream target gene of DERL1.
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Affiliation(s)
- Dejun Li
- Surgical Intensive Care Unit, Shandong Provincial Hospital Affiliated to Shandong University, Shandong University, Jinan, Shandong 250021, P.R. China
| | - Mo Shi
- Department of Thoracic Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong University, Jinan, Shandong 250021, P.R. China
| | - Hongsheng Ji
- Surgical Intensive Care Unit, Shandong Provincial Hospital Affiliated to Shandong University, Shandong University, Jinan, Shandong 250021, P.R. China
| | - Gang Chen
- Department of Thoracic Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong University, Jinan, Shandong 250021, P.R. China
| | - Hua Jiang
- Department of Thoracic Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong University, Jinan, Shandong 250021, P.R. China
| | - Zhou Wang
- Surgical Intensive Care Unit, Shandong Provincial Hospital Affiliated to Shandong University, Shandong University, Jinan, Shandong 250021, P.R. China
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11
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Ohya S, Kito H, Hatano N, Muraki K. Recent advances in therapeutic strategies that focus on the regulation of ion channel expression. Pharmacol Ther 2016; 160:11-43. [PMID: 26896566 DOI: 10.1016/j.pharmthera.2016.02.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A number of different ion channel types are involved in cell signaling networks, and homeostatic regulatory mechanisms contribute to the control of ion channel expression. Profiling of global gene expression using microarray technology has recently provided novel insights into the molecular mechanisms underlying the homeostatic and pathological control of ion channel expression. It has demonstrated that the dysregulation of ion channel expression is associated with the pathogenesis of neural, cardiovascular, and immune diseases as well as cancers. In addition to the transcriptional, translational, and post-translational regulation of ion channels, potentially important evidence on the mechanisms controlling ion channel expression has recently been accumulated. The regulation of alternative pre-mRNA splicing is therefore a novel therapeutic strategy for the treatment of dominant-negative splicing disorders. Epigenetic modification plays a key role in various pathological conditions through the regulation of pluripotency genes. Inhibitors of pre-mRNA splicing and histone deacetyalase/methyltransferase have potential as potent therapeutic drugs for cancers and autoimmune and inflammatory diseases. Moreover, membrane-anchoring proteins, lysosomal and proteasomal degradation-related molecules, auxiliary subunits, and pharmacological agents alter the protein folding, membrane trafficking, and post-translational modifications of ion channels, and are linked to expression-defect channelopathies. In this review, we focused on recent insights into the transcriptional, spliceosomal, epigenetic, and proteasomal regulation of ion channel expression: Ca(2+) channels (TRPC/TRPV/TRPM/TRPA/Orai), K(+) channels (voltage-gated, KV/Ca(2+)-activated, KCa/two-pore domain, K2P/inward-rectifier, Kir), and Ca(2+)-activated Cl(-) channels (TMEM16A/TMEM16B). Furthermore, this review highlights expression of these ion channels in expression-defect channelopathies.
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Affiliation(s)
- Susumu Ohya
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
| | - Hiroaki Kito
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan
| | - Noriyuki Hatano
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Nagoya 464-8650, Japan
| | - Katsuhiko Muraki
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Nagoya 464-8650, Japan.
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12
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Abstract
KATP channels are integral to the functions of many cells and tissues. The use of electrophysiological methods has allowed for a detailed characterization of KATP channels in terms of their biophysical properties, nucleotide sensitivities, and modification by pharmacological compounds. However, even though they were first described almost 25 years ago (Noma 1983, Trube and Hescheler 1984), the physiological and pathophysiological roles of these channels, and their regulation by complex biological systems, are only now emerging for many tissues. Even in tissues where their roles have been best defined, there are still many unanswered questions. This review aims to summarize the properties, molecular composition, and pharmacology of KATP channels in various cardiovascular components (atria, specialized conduction system, ventricles, smooth muscle, endothelium, and mitochondria). We will summarize the lessons learned from available genetic mouse models and address the known roles of KATP channels in cardiovascular pathologies and how genetic variation in KATP channel genes contribute to human disease.
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Affiliation(s)
- Monique N Foster
- Departments of Pediatrics, Physiology & Neuroscience, and Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, New York
| | - William A Coetzee
- Departments of Pediatrics, Physiology & Neuroscience, and Biochemistry and Molecular Pharmacology, NYU School of Medicine, New York, New York
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13
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Derlin-1 is overexpressed in human colon cancer and promotes cancer cell proliferation. Mol Cell Biochem 2015; 408:205-13. [PMID: 26173415 DOI: 10.1007/s11010-015-2496-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 06/18/2015] [Indexed: 01/23/2023]
Abstract
Derlin-1 is overexpressed in many types of solid tumors and plays an important role in cancer progression. However, the expression pattern and functions of Derlin-1 in human colon cancer are not fully understood. In the present study, we examined Derlin-1 expression in colon cancer cell lines and human tissues and investigated its role in colon cancer. We found that Derlin-1 expression was increased significantly in colon cancer tissues and its overexpression correlated with the tumor differentiation, Dukes stage, invasion, lymph node metastasis, distant metastasis, and poor overall survival. The silencing of Derlin-1 by shRNA led to the growth inhibition of colon cancer cells, which were associated with the promotion of apoptosis. Furthermore, Derlin-1 silencing significantly inhibited the activation of the PI3K/AKT signaling pathway. Taken together, our results showed that Derlin-1 is overexpressed in colon cancer and promotes proliferation of colon cancer cells. Derlin-1 may be a potential therapeutic target for the treatment of colon cancer.
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14
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Słomińska-Wojewódzka M, Sandvig K. The Role of Lectin-Carbohydrate Interactions in the Regulation of ER-Associated Protein Degradation. Molecules 2015; 20:9816-46. [PMID: 26023941 PMCID: PMC6272441 DOI: 10.3390/molecules20069816] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 01/08/2023] Open
Abstract
Proteins entering the secretory pathway are translocated across the endoplasmic reticulum (ER) membrane in an unfolded form. In the ER they are restricted to a quality control system that ensures correct folding or eventual degradation of improperly folded polypeptides. Mannose trimming of N-glycans on newly synthesized proteins plays an important role in the recognition and sorting of terminally misfolded glycoproteins for ER-associated protein degradation (ERAD). In this process misfolded proteins are retrotranslocated into the cytosol, polyubiquitinated, and eventually degraded by the proteasome. The mechanism by which misfolded glycoproteins are recognized and recruited to the degradation machinery has been extensively studied during last decade. In this review, we focus on ER degradation-enhancing α-mannosidase-like protein (EDEM) family proteins that seem to play a key role in the discrimination between proteins undergoing a folding process and terminally misfolded proteins directed for degradation. We describe interactions of EDEM proteins with other components of the ERAD machinery, as well as with various protein substrates. Carbohydrate-dependent interactions together with N-glycan-independent interactions seem to regulate the complex process of protein recognition and direction for proteosomal degradation.
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Affiliation(s)
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, 0379 Oslo, Norway.
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, 0379 Oslo, Norway.
- Department of Biosciences, University of Oslo, 0316 Oslo, Norway.
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15
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Martin GM, Chen PC, Devaraneni P, Shyng SL. Pharmacological rescue of trafficking-impaired ATP-sensitive potassium channels. Front Physiol 2013; 4:386. [PMID: 24399968 PMCID: PMC3870925 DOI: 10.3389/fphys.2013.00386] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/09/2013] [Indexed: 12/25/2022] Open
Abstract
ATP-sensitive potassium (KATP) channels link cell metabolism to membrane excitability and are involved in a wide range of physiological processes including hormone secretion, control of vascular tone, and protection of cardiac and neuronal cells against ischemic injuries. In pancreatic β-cells, KATP channels play a key role in glucose-stimulated insulin secretion, and gain or loss of channel function results in neonatal diabetes or congenital hyperinsulinism, respectively. The β-cell KATP channel is formed by co-assembly of four Kir6.2 inwardly rectifying potassium channel subunits encoded by KCNJ11 and four sulfonylurea receptor 1 subunits encoded by ABCC8. Many mutations in ABCC8 or KCNJ11 cause loss of channel function, thus, congenital hyperinsulinism by hampering channel biogenesis and hence trafficking to the cell surface. The trafficking defects caused by a subset of these mutations can be corrected by sulfonylureas, KATP channel antagonists that have long been used to treat type 2 diabetes. More recently, carbamazepine, an anticonvulsant that is thought to target primarily voltage-gated sodium channels has been shown to correct KATP channel trafficking defects. This article reviews studies to date aimed at understanding the mechanisms by which mutations impair channel biogenesis and trafficking and the mechanisms by which pharmacological ligands overcome channel trafficking defects. Insight into channel structure-function relationships and therapeutic implications from these studies are discussed.
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Affiliation(s)
- Gregory M Martin
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University Portland, OR, USA
| | - Pei-Chun Chen
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University Portland, OR, USA
| | - Prasanna Devaraneni
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University Portland, OR, USA
| | - Show-Ling Shyng
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University Portland, OR, USA
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16
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Chen SF, Wu CH, Lee YM, Tam K, Tsai YC, Liou JY, Shyue SK. Caveolin-1 interacts with Derlin-1 and promotes ubiquitination and degradation of cyclooxygenase-2 via collaboration with p97 complex. J Biol Chem 2013; 288:33462-9. [PMID: 24089527 DOI: 10.1074/jbc.m113.521799] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Caveolin-1 (Cav-1) interacts with and mediates protein trafficking and various cellular functions. Derlin-1 is a candidate for the retrotranslocation channel of endoplasmic reticulum proteins. However, little is known about how Derlin-1 mediates glycosylated protein degradation. Here, we identified Cav-1 as a key player in Derlin-1- and p97-mediated cyclooxygenase 2 (COX-2) ubiquitination and degradation. Derlin-1 augmented the interaction of Cav-1 and COX-2 and mediated the degradation of COX-2 in a COX-2 C terminus-dependent manner. Suppression of Cav-1 decreased the ubiquitination of COX-2, and mutation of Asn-594 to Ala to disrupt N-glycosylation at the C terminus of COX-2 reduced the interaction of COX-2 with Cav-1 but not Derlin-1. Moreover, suppression of p97 increased the ubiquitination of COX-2 and up-regulated COX-2 but not COX-1. Cav-1 enhanced the interaction of p97 with Ufd1 and Derlin-1 and collaborated with p97 to interact with COX-2. Cav-1 may be a cofactor in the interaction of Derlin-1 and N-glycosylated COX-2 and may facilitate Derlin-1- and p97 complex-mediated COX-2 ubiquitination, retrotranslocation, and degradation.
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Affiliation(s)
- Shu-Fen Chen
- From the Cardiovascular Division, Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
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17
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Cho S, Kim BY, Ahn K, Jun Y. The C-terminal amino acid of the MHC-I heavy chain is critical for binding to Derlin-1 in human cytomegalovirus US11-induced MHC-I degradation. PLoS One 2013; 8:e72356. [PMID: 23951315 PMCID: PMC3741148 DOI: 10.1371/journal.pone.0072356] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 07/11/2013] [Indexed: 11/18/2022] Open
Abstract
Derlin-1 plays a critical role in endoplasmic reticulum-associated protein degradation (ERAD) of a particular subset of proteins. Although it is generally accepted that Derlin-1 mediates the export of ERAD substrates from the ER to the cytosol, little is known about how Derlin-1 interacts with these substrates. Human cytomegalovirus (HCMV) US11 exploits Derlin-1-dependent ERAD to degrade major histocompatibility complex class I (MHC-I) molecules and evade immune surveillance. US11 requires the cytosolic tail of the MHC-I heavy chain to divert MHC-I molecules into the ERAD pathway for degradation; however, the underlying mechanisms remain unknown. Here, we show that the cytosolic tail of the MHC-I heavy chain, although not required for interaction with US11, is required for tight binding to Derlin-1 and thus for US11-induced dislocation of the MHC-I heavy chain to the cytosol for proteasomal degradation. Surprisingly, deletion of a single C-terminal amino acid from the cytosolic tail disrupted the interaction between MHC-I molecules and Derlin-1, rendering mutant MHC-I molecules resistant to US11-induced degradation. Consistently, deleting the C-terminal cytosolic region of Derlin-1 prevented it from binding to MHC-I molecules. Taken together, these results suggest that the cytosolic region of Derlin-1 is involved in ERAD substrate binding and that this interaction is critical for the Derlin-1-mediated dislocation of the MHC-I heavy chain to the cytosol during US11-induced MHC-I degradation.
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Affiliation(s)
- Sunglim Cho
- Cell Dynamics Research Center and School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Bo Young Kim
- Cell Dynamics Research Center and School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Kwangseog Ahn
- National Creative Research Initiatives Center for Antigen Presentation, Department of Biological Sciences, Seoul National University, Seoul, Korea
| | - Youngsoo Jun
- Cell Dynamics Research Center and School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, Korea
- * E-mail:
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18
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Chen PC, Olson EM, Zhou Q, Kryukova Y, Sampson HM, Thomas DY, Shyng SL. Carbamazepine as a novel small molecule corrector of trafficking-impaired ATP-sensitive potassium channels identified in congenital hyperinsulinism. J Biol Chem 2013; 288:20942-20954. [PMID: 23744072 DOI: 10.1074/jbc.m113.470948] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
ATP-sensitive potassium (KATP) channels consisting of sulfonylurea receptor 1 (SUR1) and the potassium channel Kir6.2 play a key role in insulin secretion by coupling metabolic signals to β-cell membrane potential. Mutations in SUR1 and Kir6.2 that impair channel trafficking to the cell surface lead to loss of channel function and congenital hyperinsulinism. We report that carbamazepine, an anticonvulsant, corrects the trafficking defects of mutant KATP channels previously identified in congenital hyperinsulinism. Strikingly, of the 19 SUR1 mutations examined, only those located in the first transmembrane domain of SUR1 responded to the drug. We show that unlike that reported for several other protein misfolding diseases, carbamazepine did not correct KATP channel trafficking defects by activating autophagy; rather, it directly improved the biogenesis efficiency of mutant channels along the secretory pathway. In addition to its effect on channel trafficking, carbamazepine also inhibited KATP channel activity. Upon subsequent removal of carbamazepine, however, the function of rescued channels was recovered. Importantly, combination of the KATP channel opener diazoxide and carbamazepine led to enhanced mutant channel function without carbamazepine washout. The corrector effect of carbamazepine on mutant KATP channels was also demonstrated in rat and human β-cells with an accompanying increase in channel activity. Our findings identify carbamazepine as a novel small molecule corrector that may be used to restore KATP channel expression and function in a subset of congenital hyperinsulinism patients.
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Affiliation(s)
- Pei-Chun Chen
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and
| | - Erik M Olson
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and
| | - Qing Zhou
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and
| | - Yelena Kryukova
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and
| | - Heidi M Sampson
- Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - David Y Thomas
- Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Show-Ling Shyng
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and.
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19
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Cho S, Lee M, Jun Y. Forced interaction of cell surface proteins with Derlin-1 in the endoplasmic reticulum is sufficient to induce their dislocation into the cytosol for degradation. Biochem Biophys Res Commun 2012. [PMID: 23206703 DOI: 10.1016/j.bbrc.2012.11.068] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Aberrantly folded proteins in the endoplasmic reticulum (ER) are rapidly removed into the cytosol for degradation by the proteasome via an evolutionarily conserved process termed ER-associated protein degradation (ERAD). ERAD of a subset of proteins requires Derlin-1 for dislocation into the cytosol; however, the molecular function of Derlin-1 remains unclear. Human cytomegalovirus US11 exploits Derlin-1-dependent ERAD to degrade major histocompatibility complex class I (MHC-I) molecules for immune evasion. Because US11 binds to both MHC-I molecules and Derlin-1 via its luminal and transmembrane domains (TMDs), respectively, the major role of US11 has been proposed to simply be delivery of MHC-I molecules to Derlin-1. Here, we directly tested this proposal by generating a hybrid MHC-I molecule, which contains the US11 TMD, and thus can associate with Derlin-1 in the absence of US11. Intriguingly, this MHC-I hybrid was rapidly degraded in a Derlin-1- and proteasome-dependent manner. Similarly, the vesicular stomatitis virus G protein, otherwise expressed at the cell surface, was degraded via Derlin-1-dependent ERAD when its TMD was replaced with that of US11. Thus, forced interaction of cell surface proteins with Derlin-1 is sufficient to induce their degradation via ERAD. Taken together, these results suggest that the main role of US11 is to recruit MHC-I molecules to Derlin-1, which then mediates the dislocation of MHC-I molecules into the cytosol for degradation.
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Affiliation(s)
- Sunglim Cho
- Cell Dynamics Research Center, School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea
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20
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Role of the SEL1L:LC3-I complex as an ERAD tuning receptor in the mammalian ER. Mol Cell 2012; 46:809-19. [PMID: 22633958 DOI: 10.1016/j.molcel.2012.04.017] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 09/01/2011] [Accepted: 04/12/2012] [Indexed: 11/21/2022]
Abstract
Several regulators of endoplasmic reticulum (ER)-associated degradation (ERAD) have a shorter half-life compared to conventional ER chaperones. At steady state, they are selectively removed from the ER by poorly defined events collectively referred to as ERAD tuning. Here we identify the complex comprising the type-I transmembrane protein SEL1L and the cytosolic protein LC3-I as an ERAD tuning receptor regulating the COPII-independent, vesicle-mediated removal of the lumenal ERAD regulators EDEM1 and OS-9 from the ER. Expression of folding-defective polypeptides enhances the lumenal content of EDEM1 and OS-9 by inhibiting their SEL1L:LC3-I-mediated segregation. This raises ERAD activity in the absence of UPR-induction. The mouse hepatitis virus (MHV) subverts ERAD tuning for replication. Consistently, SEL1L or LC3 silencing impair the MHV life cycle. Collectively, our data provide new molecular information about the ERAD tuning mechanisms that regulate ERAD in mammalian cells at the post translational level and how these mechanisms are hijacked by a pathogen.
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