1
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Katsuki R, Kanuka M, Ohta R, Yoshida S, Tamura T. Turnover of EDEM1, an ERAD-enhancing factor, is mediated by multiple degradation routes. Genes Cells 2024; 29:486-502. [PMID: 38682256 PMCID: PMC11163939 DOI: 10.1111/gtc.13117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 03/21/2024] [Accepted: 03/23/2024] [Indexed: 05/01/2024]
Abstract
Quality-based protein production and degradation in the endoplasmic reticulum (ER) are essential for eukaryotic cell survival. During protein maturation in the ER, misfolded or unassembled proteins are destined for disposal through a process known as ER-associated degradation (ERAD). EDEM1 is an ERAD-accelerating factor whose gene expression is upregulated by the accumulation of aberrant proteins in the ER, known as ER stress. Although the role of EDEM1 in ERAD has been studied in detail, the turnover of EDEM1 by intracellular degradation machinery, including the proteasome and autophagy, is not well understood. To clarify EDEM1 regulation in the protein level, degradation mechanism of EDEM1 was examined. Our results indicate that both ERAD and autophagy degrade EDEM1 alike misfolded degradation substrates, although each degradation machinery targets EDEM1 in different folded states of proteins. We also found that ERAD factors, including the SEL1L/Hrd1 complex, YOD1, XTP3B, ERdj3, VIMP, BAG6, and JB12, but not OS9, are involved in EDEM1 degradation in a mannose-trimming-dependent and -independent manner. Our results suggest that the ERAD accelerating factor, EDEM1, is turned over by the ERAD itself, similar to ERAD clients.
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Affiliation(s)
- Riko Katsuki
- Department of Life Science, Graduated School of Engineering ScienceAkita UniversityAkitaJapan
| | - Mai Kanuka
- Department of Life Science, Graduated School of Engineering ScienceAkita UniversityAkitaJapan
| | - Ren Ohta
- Department of Life Science, Graduated School of Engineering ScienceAkita UniversityAkitaJapan
| | - Shusei Yoshida
- Department of Life Science, Faculty of Engineering ScienceAkita UniversityAkitaJapan
| | - Taku Tamura
- Department of Life Science, Graduated School of Engineering ScienceAkita UniversityAkitaJapan
- Department of Life Science, Faculty of Engineering ScienceAkita UniversityAkitaJapan
- Present address:
Biococoon Laboratories Inc.4‐3‐5, UedaMoriokaJapan
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2
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Viruses Hijack ERAD to Regulate Their Replication and Propagation. Int J Mol Sci 2022; 23:ijms23169398. [PMID: 36012666 PMCID: PMC9408921 DOI: 10.3390/ijms23169398] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 11/25/2022] Open
Abstract
Endoplasmic reticulum-associated degradation (ERAD) is highly conserved in yeast. Recent studies have shown that ERAD is also ubiquitous and highly conserved in eukaryotic cells, where it plays an essential role in maintaining endoplasmic reticulum (ER) homeostasis. Misfolded or unfolded proteins undergo ERAD. They are recognized in the ER, retrotranslocated into the cytoplasm, and degraded by proteasomes after polyubiquitin. This may consist of several main steps: recognition of ERAD substrates, retrotranslocation, and proteasome degradation. Replication and transmission of the virus in the host is a process of a “game” with the host. It can be assumed that the virus has evolved various mechanisms to use the host’s functions for its replication and transmission, including ERAD. However, until now, it is still unclear how the host uses ERAD to deal with virus infection and how the viruses hijack the function of ERAD to obtain a favorable niche or evade the immune clearance of the host. Recent studies have shown that viruses have also evolved mechanisms to use various processes of ERAD to promote their transmission. This review describes the occurrence of ERAD and how the viruses hijack the function of ERAD to spread by affecting the homeostasis and immune response of the host, and we will focus on the role of E3 ubiquitin ligase.
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3
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Gao J, Gao A, Liu W, Chen L. Golgi stress response: A regulatory mechanism of Golgi function. Biofactors 2021; 47:964-974. [PMID: 34500494 DOI: 10.1002/biof.1780] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 08/25/2021] [Indexed: 01/09/2023]
Abstract
The organelle of eukaryotes is a finely regulated system. Once disturbed, it activates the specific autoregulatory systems, namely, organelle autoregulation. Among which, the Golgi stress response accounts for one. When the abundance and capacity of the Golgi apparatus are insufficient compared with cellular demand, the Golgi stress response is activated to enhance the function of the Golgi apparatus. Although the molecular mechanism of the Golgi stress response has not been well characterized yet, it seems to be an important part of the mammalian stress response. In this review, we discuss the current status of research on the six pathways of the mammalian Golgi stress response (the TFE3, heat shock protein 47, CREB3, E26 transformation specific, proteoglycan, and mucin pathways), which regulate the general function of the Golgi apparatus, anti-apoptosis, pro-apoptosis, proteoglycan glycosylation, and mucin glycosylation, respectively.
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Affiliation(s)
- Jiayin Gao
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
| | - Anbo Gao
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
| | - Wei Liu
- Department of Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Linxi Chen
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China
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4
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Movaqar A, Yaghoubi A, Rezaee SAR, Jamehdar SA, Soleimanpour S. Coronaviruses construct an interconnection way with ERAD and autophagy. Future Microbiol 2021; 16:1135-1151. [PMID: 34468179 PMCID: PMC8412035 DOI: 10.2217/fmb-2021-0044] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 08/04/2021] [Indexed: 12/20/2022] Open
Abstract
Coronaviruses quickly became a pandemic or epidemic, affecting large numbers of humans, due to their structural features and also because of their impacts on intracellular communications. The knowledge of the intracellular mechanism of virus distribution could help understand the coronavirus's proper effects on different pathways that lead to the infections. They protect themselves from recognition and damage the infected cell by using an enclosed membrane through hijacking the autophagy and endoplasmic reticulum-associated protein degradation pathways. The present study is a comprehensive review of the coronavirus strategy in upregulating the communication network of autophagy and endoplasmic reticulum-associated protein degradation.
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Affiliation(s)
- Aref Movaqar
- Antimicrobial Resistance Research Center, Mashhad University of Medical Science, Mashhad, Iran
- Department of Microbiology & Virology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Atieh Yaghoubi
- Antimicrobial Resistance Research Center, Mashhad University of Medical Science, Mashhad, Iran
- Department of Microbiology & Virology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - SA Rahim Rezaee
- Inflammation & Inflammatory Diseases Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Saeid A Jamehdar
- Antimicrobial Resistance Research Center, Mashhad University of Medical Science, Mashhad, Iran
- Department of Microbiology & Virology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Saman Soleimanpour
- Antimicrobial Resistance Research Center, Mashhad University of Medical Science, Mashhad, Iran
- Department of Microbiology & Virology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
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5
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Stepanenko OV, Sulatsky MI, Mikhailova EV, Stepanenko OV, Kuznetsova IM, Turoverov KK, Sulatskaya AI. Trypsin Induced Degradation of Amyloid Fibrils. Int J Mol Sci 2021; 22:4828. [PMID: 34063223 PMCID: PMC8124345 DOI: 10.3390/ijms22094828] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/26/2021] [Accepted: 04/30/2021] [Indexed: 02/06/2023] Open
Abstract
Proteolytic enzymes are known to be involved in the formation and degradation of various monomeric proteins, but the effect of proteases on the ordered protein aggregates, amyloid fibrils, which are considered to be extremely stable, remains poorly understood. In this work we study resistance to proteolytic degradation of lysozyme amyloid fibrils with two different types of morphology and beta-2-microglobulun amyloids. We showed that the proteolytic enzyme of the pancreas, trypsin, induced degradation of amyloid fibrils, and the mechanism of this process was qualitatively the same for all investigated amyloids. At the same time, we found a dependence of efficiency and rate of fibril degradation on the structure of the amyloid-forming protein as well as on the morphology and clustering of amyloid fibrils. It was assumed that the discovered relationship between fibrils structure and the efficiency of their degradation by trypsin can become the basis of a new express method for the analysis of amyloids polymorphism. Unexpectedly lower resistance of both types of lysozyme amyloids to trypsin exposure compared to the native monomeric protein (which is not susceptible to hydrolysis) was attributed to the higher availability of cleavage sites in studied fibrils. Another intriguing result of the work is that the cytotoxicity of amyloids treated with trypsin was not only failing to decline, but even increasing in the case of beta-2-microglobulin fibrils.
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Affiliation(s)
- Olga V. Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Avenue, 194064 St. Petersburg, Russia; (O.V.S.); (E.V.M.); (O.V.S.); (I.M.K.); (A.I.S.)
| | - Maksim I. Sulatsky
- Laboratory of Cell Morphology, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Avenue, 194064 St. Petersburg, Russia;
| | - Ekaterina V. Mikhailova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Avenue, 194064 St. Petersburg, Russia; (O.V.S.); (E.V.M.); (O.V.S.); (I.M.K.); (A.I.S.)
| | - Olesya V. Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Avenue, 194064 St. Petersburg, Russia; (O.V.S.); (E.V.M.); (O.V.S.); (I.M.K.); (A.I.S.)
| | - Irina M. Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Avenue, 194064 St. Petersburg, Russia; (O.V.S.); (E.V.M.); (O.V.S.); (I.M.K.); (A.I.S.)
| | - Konstantin K. Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Avenue, 194064 St. Petersburg, Russia; (O.V.S.); (E.V.M.); (O.V.S.); (I.M.K.); (A.I.S.)
- Institute of Physics, Nanotechnology and Telecommunications, Peter the Great St. Petersburg Polytechnic University, Polytechnicheskaya 29, 195251 St. Petersburg, Russia
| | - Anna I. Sulatskaya
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Avenue, 194064 St. Petersburg, Russia; (O.V.S.); (E.V.M.); (O.V.S.); (I.M.K.); (A.I.S.)
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6
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Bhattacharya A, Qi L. ER-associated degradation in health and disease - from substrate to organism. J Cell Sci 2019; 132:132/23/jcs232850. [PMID: 31792042 DOI: 10.1242/jcs.232850] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The recent literature has revolutionized our view on the vital importance of endoplasmic reticulum (ER)-associated degradation (ERAD) in health and disease. Suppressor/enhancer of Lin-12-like (Sel1L)-HMG-coA reductase degradation protein 1 (Hrd1)-mediated ERAD has emerged as a crucial determinant of normal physiology and as a sentinel against disease pathogenesis in the body, in a largely substrate- and cell type-specific manner. In this Review, we highlight three features of ERAD, constitutive versus inducible ERAD, quality versus quantity control of ERAD and ERAD-mediated regulation of nuclear gene transcription, through which ERAD exerts a profound impact on a number of physiological processes.
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Affiliation(s)
- Asmita Bhattacharya
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48105, USA.,Graduate Program of Genetics, Genomics and Development, Cornell University, Ithaca, NY 14853, USA
| | - Ling Qi
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48105, USA .,Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48105, USA
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7
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Lamriben L, Oster ME, Tamura T, Tian W, Yang Z, Clausen H, Hebert DN. EDEM1's mannosidase-like domain binds ERAD client proteins in a redox-sensitive manner and possesses catalytic activity. J Biol Chem 2018; 293:13932-13945. [PMID: 30021839 DOI: 10.1074/jbc.ra118.004183] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 06/26/2018] [Indexed: 11/06/2022] Open
Abstract
Endoplasmic reticulum (ER) degradation-enhancing α-mannosidase-like 1 protein (EDEM1) is a protein quality control factor that was initially proposed to recognize N-linked glycans on misfolded proteins through its mannosidase-like domain (MLD). However, recent studies have demonstrated that EDEM1 binds to some misfolded proteins in a glycan-independent manner, suggesting a more complex binding landscape for EDEM1. In this study, we have identified a thiol-dependent substrate interaction between EDEM1 and the α1-antitrypsin ER-associated protein degradation (ERAD) clients Z and NHK, specifically through the single Cys residue on Z/NHK (Cys256), required for binding under stringent detergent conditions. In addition to the thiol-dependent interaction, the presence of weaker protein-protein interactions was confirmed, suggestive of bipartite client-binding properties. About four reactive thiols on EDEM1 were identified and were not directly responsible for the observed redox-sensitive binding by EDEM1. Moreover, a protein construct comprising the EDEM1 MLD had thiol-dependent binding properties along with its active glycan-trimming activities. Lastly, we identified an additional intrinsically disordered region (IDR) located at the C terminus of EDEM1 in addition to its previously identified N-terminal IDR. We also determined that both IDRs are required for binding to the ERAD component ERdj5 as an interaction with ERdj5 was not observed with the MLD alone. Together, our findings indicate that EDEM1 employs different binding modalities to interact with ERAD clients and ER quality control (ERQC) machinery partners and that some of these properties are shared with its homologues EDEM2 and EDEM3.
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Affiliation(s)
- Lydia Lamriben
- From the Department of Biochemistry and Molecular Biology and.,Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Massachusetts 01003 and
| | - Michela E Oster
- From the Department of Biochemistry and Molecular Biology and
| | - Taku Tamura
- From the Department of Biochemistry and Molecular Biology and
| | - Weihua Tian
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Zhang Yang
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Daniel N Hebert
- From the Department of Biochemistry and Molecular Biology and .,Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Massachusetts 01003 and
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8
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Ortíz-Rentería M, Juárez-Contreras R, González-Ramírez R, Islas LD, Sierra-Ramírez F, Llorente I, Simon SA, Hiriart M, Rosenbaum T, Morales-Lázaro SL. TRPV1 channels and the progesterone receptor Sig-1R interact to regulate pain. Proc Natl Acad Sci U S A 2018; 115:E1657-E1666. [PMID: 29378958 PMCID: PMC5816171 DOI: 10.1073/pnas.1715972115] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Transient Receptor Potential Vanilloid 1 (TRPV1) ion channel is expressed in nociceptors where, when activated by chemical or thermal stimuli, it functions as an important transducer of painful and itch-related stimuli. Although the interaction of TRPV1 with proteins that regulate its function has been previously explored, their modulation by chaperones has not been elucidated, as is the case for other mammalian TRP channels. Here we show that TRPV1 physically interacts with the Sigma 1 Receptor (Sig-1R), a chaperone that binds progesterone, an antagonist of Sig-1R and an important neurosteroid associated to the modulation of pain. Antagonism of Sig-1R by progesterone results in the down-regulation of TRPV1 expression in the plasma membrane of sensory neurons and, consequently, a decrease in capsaicin-induced nociceptive responses. This is observed both in males treated with a synthetic antagonist of Sig-1R and in pregnant females where progesterone levels are elevated. This constitutes a previously undescribed mechanism by which TRPV1-dependent nociception and pain can be regulated.
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Affiliation(s)
- Miguel Ortíz-Rentería
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Rebeca Juárez-Contreras
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Ricardo González-Ramírez
- Departamento de Biología Molecular e Histocompatibilidad, Hospital General Dr. Manuel Gea González, Secretaría de Salud, 14080 Tlalpan, Ciudad de México, México
| | - León D Islas
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Félix Sierra-Ramírez
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Itzel Llorente
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Sidney A Simon
- Department of Neurobiology, Duke University, Durham, NC 27710
| | - Marcia Hiriart
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Tamara Rosenbaum
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México
| | - Sara L Morales-Lázaro
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Coyoacán, Ciudad de México, México;
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9
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Wang T, Wang B, Huang H, Zhang C, Zhu Y, Pei B, Cheng C, Sun L, Wang J, Jin Q, Zhao Z. Enterovirus 71 protease 2Apro and 3Cpro differentially inhibit the cellular endoplasmic reticulum-associated degradation (ERAD) pathway via distinct mechanisms, and enterovirus 71 hijacks ERAD component p97 to promote its replication. PLoS Pathog 2017; 13:e1006674. [PMID: 28985237 PMCID: PMC5650186 DOI: 10.1371/journal.ppat.1006674] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 10/20/2017] [Accepted: 09/28/2017] [Indexed: 11/19/2022] Open
Abstract
Endoplasmic reticulum-associated degradation (ERAD) is an important function for cellular homeostasis. The mechanism of how picornavirus infection interferes with ERAD remains unclear. In this study, we demonstrated that enterovirus 71 (EV71) infection significantly inhibits cellular ERAD by targeting multiple key ERAD molecules with its proteases 2Apro and 3Cpro using different mechanisms. Ubc6e was identified as the key E2 ubiquitin-conjugating enzyme in EV71 disturbed ERAD. EV71 3Cpro cleaves Ubc6e at Q219G, Q260S, and Q273G. EV71 2Apro mainly inhibits the de novo synthesis of key ERAD molecules Herp and VIMP at the protein translational level. Herp differentially participates in the degradation of different glycosylated ERAD substrates α-1 antitrypsin Null Hong Kong (NHK) and the C-terminus of sonic hedgehog (SHH-C) via unknown mechanisms. p97 was identified as a host factor in EV71 replication; it redistributed and co-exists with the viral protein and other known replication-related molecules in EV71-induced replication organelles. Electron microscopy and multiple-color confocal assays also showed that EV71-induced membranous vesicles were closely associated with the endoplasmic reticulum (ER), and the ER membrane molecule RTN3 was redistributed to the viral replication complex during EV71 infection. Therefore, we propose that EV71 rearranges ER membranes and hijacks p97 from cellular ERAD to benefit its replication. These findings add to our understanding of how viruses disturb ERAD and provide potential anti-viral targets for EV71 infection.
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Affiliation(s)
- Tao Wang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Bei Wang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - He Huang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Chongyang Zhang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Yuanmei Zhu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Bin Pei
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Chaofei Cheng
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Lei Sun
- Center for Biological Imaging, Institute of Biophysics, Chinese Academy of Sciences, Beijing, PR China
| | - Jianwei Wang
- MOH Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory, IPB, CAMS-Fondation Mérieux, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
- * E-mail: (JWW); (QJ); (ZDZ)
| | - Qi Jin
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
- * E-mail: (JWW); (QJ); (ZDZ)
| | - Zhendong Zhao
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
- Center of Clinical Immunology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
- CAMS-Oxford University International Center for Translational Immunology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
- * E-mail: (JWW); (QJ); (ZDZ)
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10
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Buaillon C, Guerrero NA, Cebrian I, Blanié S, Lopez J, Bassot E, Vasseur V, Santi-Rocca J, Blanchard N. MHC I presentation of Toxoplasma gondii immunodominant antigen does not require Sec22b and is regulated by antigen orientation at the vacuole membrane. Eur J Immunol 2017; 47:1160-1170. [PMID: 28508576 DOI: 10.1002/eji.201646859] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 03/21/2017] [Accepted: 05/09/2017] [Indexed: 12/16/2022]
Abstract
The intracellular Toxoplasma gondii parasite replicates within a parasitophorous vacuole (PV). T. gondii secretes proteins that remain soluble in the PV space, are inserted into PV membranes or are exported beyond the PV boundary. In addition to supporting T. gondii growth, these proteins can be processed and presented by MHC I for CD8+ T-cell recognition. Yet it is unclear whether membrane binding influences the processing pathways employed and if topology of membrane antigens impacts their MHC I presentation. Here we report that the MHC I pathways of soluble and membrane-bound antigens differ in their requirement for host ER recruitment. In contrast to the soluble SAG1-OVA model antigen, we find that presentation of the membrane-bound GRA6 is independent from the SNARE Sec22b, a key molecule for transfer of host endoplasmic reticulum components onto the PV. Using parasites modified to secrete a transmembrane antigen with opposite orientations, we further show that MHC I presentation is highly favored when the C-terminal epitope is exposed to the host cell cytosol, which corresponds to GRA6 natural orientation. Our data suggest that the biochemical properties of antigens released by intracellular pathogens critically guide their processing pathway and are valuable parameters to consider for vaccination strategies.
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Affiliation(s)
- Célia Buaillon
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| | - Nestor A Guerrero
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| | - Ignacio Cebrian
- Instituto de Histología y Embriología de Mendoza (IHEM)-CONICET/UNCuyo, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Sophie Blanié
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| | - Jodie Lopez
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| | - Emilie Bassot
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| | - Virginie Vasseur
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| | - Julien Santi-Rocca
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| | - Nicolas Blanchard
- Centre de Physiopathologie Toulouse Purpan (CPTP), INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
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11
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Chen Q, Liu R, Wang Q, Xie Q. ERAD Tuning of the HRD1 Complex Component AtOS9 Is Modulated by an ER-Bound E2, UBC32. MOLECULAR PLANT 2017; 10:891-894. [PMID: 28040559 DOI: 10.1016/j.molp.2016.12.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 12/08/2016] [Accepted: 12/20/2016] [Indexed: 06/06/2023]
Affiliation(s)
- Qian Chen
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing, 100101, P. R. China; The Faculty of Life Science, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Ruijun Liu
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing, 100101, P. R. China; The Faculty of Life Science, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Qian Wang
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing, 100101, P. R. China; The Faculty of Life Science, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Qi Xie
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing, 100101, P. R. China; The Faculty of Life Science, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
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12
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Fujihira H, Masahara-Negishi Y, Tamura M, Huang C, Harada Y, Wakana S, Takakura D, Kawasaki N, Taniguchi N, Kondoh G, Yamashita T, Funakoshi Y, Suzuki T. Lethality of mice bearing a knockout of the Ngly1-gene is partially rescued by the additional deletion of the Engase gene. PLoS Genet 2017; 13:e1006696. [PMID: 28426790 PMCID: PMC5398483 DOI: 10.1371/journal.pgen.1006696] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 03/15/2017] [Indexed: 11/25/2022] Open
Abstract
The cytoplasmic peptide:N-glycanase (Ngly1 in mammals) is a de-N-glycosylating enzyme that is highly conserved among eukaryotes. It was recently reported that subjects harboring mutations in the NGLY1 gene exhibited severe systemic symptoms (NGLY1-deficiency). While the enzyme obviously has a critical role in mammals, its precise function remains unclear. In this study, we analyzed Ngly1-deficient mice and found that they are embryonic lethal in C57BL/6 background. Surprisingly, the additional deletion of the gene encoding endo-β-N-acetylglucosaminidase (Engase), which is another de-N-glycosylating enzyme but leaves a single GlcNAc at glycosylated Asn residues, resulted in the partial rescue of the lethality of the Ngly1-deficient mice. Additionally, we also found that a change in the genetic background of C57BL/6 mice, produced by crossing the mice with an outbred mouse strain (ICR) could partially rescue the embryonic lethality of Ngly1-deficient mice. Viable Ngly1-deficient mice in a C57BL/6 and ICR mixed background, however, showed a very severe phenotype reminiscent of the symptoms of NGLY1-deficiency subjects. Again, many of those defects were strongly suppressed by the additional deletion of Engase in the C57BL/6 and ICR mixed background. The defects observed in Ngly1/Engase-deficient mice (C57BL/6 background) and Ngly1-deficient mice (C57BL/6 and ICR mixed background) closely resembled some of the symptoms of patients with an NGLY1-deficiency. These observations strongly suggest that the Ngly1- or Ngly1/Engase-deficient mice could serve as a valuable animal model for studies related to the pathogenesis of the NGLY1-deficiency, and that cytoplasmic ENGase represents one of the potential therapeutic targets for this genetic disorder. Ngly1 is a cytoplasmic de-N-glycosylating enzyme that is ubiquitously found in eukaryotes. This enzyme is involved in a process referred to as endoplasmic reticulum-associated degradation (ERAD), one of the quality control mechanisms for newly synthesized proteins. A genetic disorder, NGLY1-deficiency, caused by mutations in the NGLY1 gene has recently been discovered. However, the precise mechanism for the pathogenesis of this devastating disease continues to remain unclear. We report herein that Ngly1-deficient mice are embryonically lethal in a C57BL/6 background. Surprisingly, the lethality was suppressed by crossing the mice with an outbred mouse strain (ICR), suggesting that the phenotypic consequence of Ngly1 is greatly influenced by their genetic background. In both cases, the additional deletion of Engase in Ngly1-deficient mice could strongly mitigate the phenotypes. Interestingly, the remaining defects in Ngly1-deficient or Ngly1/Engase-deficient mice were reminiscent of the symptoms of subjects with an NGLY1-deficiency. Our results clearly point to the importance of Ngly1 in mammals and show that the inhibition of ENGase represents an effective therapy for treating an NGLY1-deficiency. Most importantly, the mice described herein could serve as valuable viable model mice for studies related to the pathophysiology of an NGLY1-deficiency.
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Affiliation(s)
- Haruhiko Fujihira
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, Saitama, Japan
| | - Yuki Masahara-Negishi
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, Saitama, Japan
| | - Masaru Tamura
- Technology and Development Team for Mouse Phenotype Analysis, Japan Mouse Clinic, BioResourse Center, RIKEN, Ibaraki, Japan
| | - Chengcheng Huang
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, Saitama, Japan
| | - Yoichiro Harada
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, Saitama, Japan
| | - Shigeharu Wakana
- Technology and Development Team for Mouse Phenotype Analysis, Japan Mouse Clinic, BioResourse Center, RIKEN, Ibaraki, Japan
| | - Daisuke Takakura
- Graduate School of Medical Life Science, Yokohama City University, Kanagawa, Japan
| | - Nana Kawasaki
- Graduate School of Medical Life Science, Yokohama City University, Kanagawa, Japan
| | - Naoyuki Taniguchi
- Disease Glycomics Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, Saitama, Japan
| | - Gen Kondoh
- Laboratory of Integrative Biological Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Tadashi Yamashita
- Laboratory of Biochemistry, School of Veterinary Medicine, Azabu University, Kanagawa, Japan
| | - Yoko Funakoshi
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, Saitama, Japan
| | - Tadashi Suzuki
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, Saitama, Japan
- * E-mail:
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13
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Erzurumlu Y, Ballar P. Androgen Mediated Regulation of Endoplasmic Reticulum-Associated Degradation and its Effects on Prostate Cancer. Sci Rep 2017; 7:40719. [PMID: 28091582 PMCID: PMC5238502 DOI: 10.1038/srep40719] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 12/09/2016] [Indexed: 12/12/2022] Open
Abstract
The endoplasmic reticulum (ER) comprises thirty percent of the newly translated proteins in eukaryotic cells. The quality control mechanism within the ER distinguishes between properly and improperly folded proteins and ensures that unwanted proteins are retained in the ER and subsequently degraded through ER-associated degradation (ERAD). Besides cleaning of misfolded proteins ERAD is also important for physiological processes by regulating the abundance of normal proteins of the ER. Thus it is important to unreveal the regulation patterns of ERAD. Here, we describe that ERAD pathway is regulated by androgen, where its inhibitor SVIP was downregulated, all other ERAD genes were upregulated. Consistently, androgen treatment increased the degradation rate of ERAD substrates. Using several independent techniques, we showed that this regulation is through androgen receptor transactivation. ERAD genes found to be upregulated in prostate cancer tissues and silencing expression of Hrd1, SVIP, and gp78 reduced the in vitro migration and malignant transformation of LNCaP cells. Our data suggests that expression levels of ERAD components are regulated by androgens, that promotes ERAD proteolytic activity, which is positively related with prostate tumorigenesis.
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Affiliation(s)
- Yalcin Erzurumlu
- Ege University, Faculty of Pharmacy, Biochemistry Department, Izmir, 35100 Turkey
| | - Petek Ballar
- Ege University, Faculty of Pharmacy, Biochemistry Department, Izmir, 35100 Turkey
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14
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Hansen HG, Pristovšek N, Kildegaard HF, Lee GM. Improving the secretory capacity of Chinese hamster ovary cells by ectopic expression of effector genes: Lessons learned and future directions. Biotechnol Adv 2017; 35:64-76. [DOI: 10.1016/j.biotechadv.2016.11.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 11/12/2016] [Accepted: 11/28/2016] [Indexed: 12/12/2022]
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15
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Dubnikov T, Ben-Gedalya T, Reiner R, Hoepfner D, Cabral WA, Marini JC, Cohen E. PrP-containing aggresomes are cytosolic components of an ER quality control mechanism. J Cell Sci 2016; 129:3635-3647. [PMID: 27550517 DOI: 10.1242/jcs.186981] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 08/13/2016] [Indexed: 11/20/2022] Open
Abstract
Limited detoxification capacity often directs aggregation-prone, potentially hazardous, misfolded proteins to be deposited in designated cytosolic compartments known as 'aggresomes'. The roles of aggresomes as cellular quality control centers, and the cellular origin of the deposits contained within these structures, remain to be characterized. Here, we utilized the observation that the prion protein (PrP, also known as PRNP) accumulates in aggresomes following the inhibition of folding chaperones, members of the cyclophilin family, to address these questions. We found that misfolded PrP molecules must pass through the endoplasmic reticulum (ER) in order to be deposited in aggresomes, that the Golgi plays no role in this process and that cytosolic PrP species are not deposited in pre-existing aggresomes. Prior to their deposition in the aggresome, PrP molecules lose the ER localization signal and have to acquire a GPI anchor. Our discoveries indicate that PrP aggresomes are cytosolic overflow deposition centers for the ER quality control mechanisms and highlight the importance of these structures for the maintenance of protein homeostasis within the ER.
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Affiliation(s)
- Tatyana Dubnikov
- Biochemistry and Molecular Biology, the Institute for Medical Research Israel - Canada (IMRIC), the School of Medicine of the Hebrew University of Jerusalem, Jerusalem 91120, Israel
| | - Tziona Ben-Gedalya
- Biochemistry and Molecular Biology, the Institute for Medical Research Israel - Canada (IMRIC), the School of Medicine of the Hebrew University of Jerusalem, Jerusalem 91120, Israel Department of Obstetrics and Gynecology, Hadassah University Hospital, Ein Kerem, Jerusalem, 91120, Israel
| | - Robert Reiner
- Biochemistry and Molecular Biology, the Institute for Medical Research Israel - Canada (IMRIC), the School of Medicine of the Hebrew University of Jerusalem, Jerusalem 91120, Israel
| | - Dominic Hoepfner
- Novartis Institutes for BioMedical Research, Novartis Campus, Basel 4056, Switzerland
| | - Wayne A Cabral
- Bone and Extracellular Matrix Branch, NICHD, NIH, Bethesda, MD 20892, USA
| | - Joan C Marini
- Bone and Extracellular Matrix Branch, NICHD, NIH, Bethesda, MD 20892, USA
| | - Ehud Cohen
- Biochemistry and Molecular Biology, the Institute for Medical Research Israel - Canada (IMRIC), the School of Medicine of the Hebrew University of Jerusalem, Jerusalem 91120, Israel
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16
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Franco ML, Melero C, Sarasola E, Acebo P, Luque A, Calatayud-Baselga I, García-Barcina M, Vilar M. Mutations in TrkA Causing Congenital Insensitivity to Pain with Anhidrosis (CIPA) Induce Misfolding, Aggregation, and Mutation-dependent Neurodegeneration by Dysfunction of the Autophagic Flux. J Biol Chem 2016; 291:21363-21374. [PMID: 27551041 DOI: 10.1074/jbc.m116.722587] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 08/19/2016] [Indexed: 12/21/2022] Open
Abstract
Congenital insensitivity to pain with anhidrosis (CIPA) is a rare autosomal recessive disorder characterized by insensitivity to noxious stimuli and variable intellectual disability (ID) due to mutations in the NTRK1 gene encoding the NGF receptor TrkA. To get an insight in the effect of NTRK1 mutations in the cognitive phenotype we biochemically characterized three TrkA mutations identified in children diagnosed of CIPA with variable ID. These mutations are located in different domains of the protein; L213P in the extracellular domain, Δ736 in the kinase domain, and C300stop in the extracellular domain, a new mutation causing CIPA diagnosed in a Spanish teenager. We found that TrkA mutations induce misfolding, retention in the endoplasmic reticulum (ER), and aggregation in a mutation-dependent manner. The distinct mutations are degraded with a different kinetics by different ER quality control mechanisms; although C300stop is rapidly disposed by autophagy, Δ736 degradation is sensitive to the proteasome and to autophagy inhibitors, and L213P is a long-lived protein refractory to degradation. In addition L213P enhances the formation of autophagic vesicles triggering an increase in the autophagic flux with deleterious consequences. Mouse cortical neurons expressing L213P showed the accumulation of LC3-GFP positive puncta and dystrophic neurites. Our data suggest that TrkA misfolding and aggregation induced by some CIPA mutations disrupt the autophagy homeostasis causing neurodegeneration. We propose that distinct disease-causing mutations of TrkA generate different levels of cell toxicity, which may provide an explanation of the variable intellectual disability observed in CIPA patients.
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Affiliation(s)
- María Luisa Franco
- From the Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València, IBV-CSIC, c/o Jaume Roig 11, 46010 València,
| | - Cristina Melero
- From the Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València, IBV-CSIC, c/o Jaume Roig 11, 46010 València,
| | - Esther Sarasola
- the Department of Genetics, Basurto University Hospital (osakidetza/Servicio Vasco de Salud), Bilbao, and
| | | | - Alfonso Luque
- Rare Disease Centers, ISCIII, Crta. Majadahonda a Pozuelo km.2 Majadahonda, Madrid 28220, Spain
| | - Isabel Calatayud-Baselga
- From the Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València, IBV-CSIC, c/o Jaume Roig 11, 46010 València,
| | - María García-Barcina
- the Department of Genetics, Basurto University Hospital (osakidetza/Servicio Vasco de Salud), Bilbao, and
| | - Marçal Vilar
- From the Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València, IBV-CSIC, c/o Jaume Roig 11, 46010 València,,
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17
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Barrera MJ, Aguilera S, Castro I, Cortés J, Bahamondes V, Quest AFG, Molina C, González S, Hermoso M, Urzúa U, Leyton C, González MJ. Pro-inflammatory cytokines enhance ERAD and ATF6α pathway activity in salivary glands of Sjögren's syndrome patients. J Autoimmun 2016; 75:68-81. [PMID: 27461470 DOI: 10.1016/j.jaut.2016.07.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 06/21/2016] [Accepted: 07/15/2016] [Indexed: 12/12/2022]
Abstract
Salivary gland (SG) acinar-cells are susceptible to endoplasmic reticulum (ER) stress related to their secretory activity and the complexity of synthesized secretory products. SGs of Sjögren's syndrome patients (SS)-patients show signs of inflammation and altered proteostasis, associated with low IRE1α/XBP-1 pathway activity without avert increases in apoptosis. Acinar-cells may avoid apoptosis by activation of the ATF6α pathway and ER-associated protein degradation (ERAD). The aim of this study was to evaluate the role of pro-inflammatory cytokines in ATF6α pathway/ERAD activation and cell viability in labial salivary glands (LSG) of SS-patients. In biopsies from SS-patients increased ATF6α signaling pathway activity, as evidenced by generation of the ATF6f cleavage fragment, and increased expression of ERAD machinery components, such as EDEM1, p97, SEL1L, gp78, UBE2J1, UBE2G2, HERP and DERLIN1, were observed compared to controls. Alternatively, for pro- (active-caspase-3) and anti-apoptotic (cIAP2) markers no significant difference between the two experimental groups was detected. Increased presence of ATF6f and ERAD molecules correlated significantly with increased expression of pro-inflammatory cytokines. These observations were corroborated in vitro in 3D-acini treated with TNF-α and/or IFN-γ, where an increase in the expression and activation of the ATF6α sensor and ERAD machinery components was detected under ER stress conditions, while changes in cell viability and caspase-3 activation were not observed. Cytokine stimulation protected cells from death when co-incubated with an ERAD machinery inhibitor. Alternatively, when cytokines were eliminated from the medium prior to ERAD inhibition, cell death increased, suggesting that the presence of pro-inflammatory cytokines in the medium is essential to maintain cell viability. In conclusion, the ATF6α pathway and the ERAD machinery are active in LSG of SS-patients. Both were also activated by TNF-α and IFN-γ in vitro in 3D-acini and aided in preventing apoptosis. IFN-γ levels were elevated in SS-patients and UPR responses triggered in vitro by this cytokine closely matched those observed in LSG from SS-patients, suggesting that cytokines may induce ER stress.
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Affiliation(s)
- María-José Barrera
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Sergio Aguilera
- Departamento de Reumatología, Clínica INDISA, Santiago, Chile
| | - Isabel Castro
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Juan Cortés
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Verónica Bahamondes
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Andrew F G Quest
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile; Center for Molecular Studies of the Cell (CEMC), Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Claudio Molina
- Escuela Dental, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - Sergio González
- Escuela Dental, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - Marcela Hermoso
- Programa de Inmunología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Ulises Urzúa
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Cecilia Leyton
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - María-Julieta González
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile.
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18
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Di XJ, Wang YJ, Han DY, Fu YL, Duerfeldt AS, Blagg BSJ, Mu TW. Grp94 Protein Delivers γ-Aminobutyric Acid Type A (GABAA) Receptors to Hrd1 Protein-mediated Endoplasmic Reticulum-associated Degradation. J Biol Chem 2016; 291:9526-39. [PMID: 26945068 DOI: 10.1074/jbc.m115.705004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Indexed: 11/06/2022] Open
Abstract
Proteostasis maintenance of γ-aminobutyric acid type A (GABAA) receptors dictates their function in controlling neuronal inhibition in mammalian central nervous systems. However, as a multisubunit, multispan, integral membrane protein, even wild type subunits of GABAA receptors fold and assemble inefficiently in the endoplasmic reticulum (ER). Unassembled and misfolded subunits undergo ER-associated degradation (ERAD), but this degradation process remains poorly understood for GABAA receptors. Here, using the α1 subunits of GABAA receptors as a model substrate, we demonstrated that Grp94, a metazoan-specific Hsp90 in the ER lumen, uses its middle domain to interact with the α1 subunits and positively regulates their ERAD. OS-9, an ER-resident lectin, acts downstream of Grp94 to further recognize misfolded α1 subunits in a glycan-dependent manner. This delivers misfolded α1 subunits to the Hrd1-mediated ubiquitination and the valosin-containing protein-mediated extraction pathway. Repressing the initial ERAD recognition step by inhibiting Grp94 enhances the functional surface expression of misfolding-prone α1(A322D) subunits, which causes autosomal dominant juvenile myoclonic epilepsy. This study clarifies a Grp94-mediated ERAD pathway for GABAA receptors, which provides a novel way to finely tune their function in physiological and pathophysiological conditions.
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Affiliation(s)
- Xiao-Jing Di
- From the Department of Physiology and Biophysics
| | - Ya-Juan Wang
- Center for Proteomics and Bioinformatics and Department of Epidemiology and Biostatistics, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Dong-Yun Han
- From the Department of Physiology and Biophysics
| | - Yan-Lin Fu
- From the Department of Physiology and Biophysics
| | - Adam S Duerfeldt
- the Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, and
| | - Brian S J Blagg
- the Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045
| | - Ting-Wei Mu
- From the Department of Physiology and Biophysics,
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19
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Pisoni GB, Molinari M. Five Questions (with their Answers) on ER-Associated Degradation. Traffic 2016; 17:341-50. [PMID: 27004930 DOI: 10.1111/tra.12373] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/06/2016] [Accepted: 01/06/2016] [Indexed: 01/17/2023]
Abstract
Production of a functional proteome is a major burden for our cells. Native proteins operate inside and outside the cells to eventually warrant life and adaptation to metabolic and environmental changes, there is no doubt that production and inappropriate handling of misfolded proteins may cause severe disease states. This review focuses on protein destruction, which is, paradoxically, a crucial event for cell and organism survival. It regulates the physiological turnover of proteins and the clearance of faulty biosynthetic products. It mainly relies on the intervention of two catabolic machineries, the ubiquitin proteasome system and the (auto)lysosomal system. Here, we have selected five questions dealing with how, why and when proteins produced in the mammalian endoplasmic reticulum are eventually selected for destruction.
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Affiliation(s)
- Giorgia Brambilla Pisoni
- Institute for Research in Biomedicine, CH-6500, Bellinzona, Switzerland.,Università della Svizzera italiana, CH-6900, Lugano, Switzerland.,ETH Zurich, D-BIOL, 8093, Zurich, Switzerland
| | - Maurizio Molinari
- Institute for Research in Biomedicine, CH-6500, Bellinzona, Switzerland.,Università della Svizzera italiana, CH-6900, Lugano, Switzerland.,School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
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20
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Jan Bergmann T, Brambilla Pisoni G, Molinari M. Quality control mechanisms of protein biogenesis: proteostasis dies hard. AIMS BIOPHYSICS 2016. [DOI: 10.3934/biophy.2016.4.456] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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21
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Karademir B, Corek C, Ozer NK. Endoplasmic reticulum stress and proteasomal system in amyotrophic lateral sclerosis. Free Radic Biol Med 2015; 88:42-50. [PMID: 26073124 DOI: 10.1016/j.freeradbiomed.2015.05.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 05/18/2015] [Accepted: 05/26/2015] [Indexed: 12/14/2022]
Abstract
Protein processing including folding, unfolding and degradation is involved in the mechanisms of many diseases. Unfolded protein response and/or endoplasmic reticulum stress are accepted to be the first steps which should be completed via protein degradation. In this direction, proteasomal system and autophagy play important role as the degradation pathways and controlled via complex mechanisms. Amyotrophic lateral sclerosis is a multifactorial neurodegenerative disease which is also known as the most catastrophic one. Mutation of many different genes are involved in the pathogenesis such as superoxide dismutase 1, chromosome 9 open reading frame 72 and ubiquilin 2. These genes are mainly related to the antioxidant defense systems, endoplasmic reticulum stress related proteins and also protein aggregation, degradation pathways and therefore mutation of these genes cause related disorders.This review focused on the role of protein processing via endoplasmic reticulum and proteasomal system in amyotrophic lateral sclerosis which are the main players in the pathology. In this direction, dysfunction of endoplasmic reticulum associated degradation and related cell death mechanisms that are autophagy/apoptosis have been detailed.
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Affiliation(s)
- Betul Karademir
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center (GEMHAM), Marmara University, 34854 Maltepe, Istanbul, Turkey
| | - Ceyda Corek
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center (GEMHAM), Marmara University, 34854 Maltepe, Istanbul, Turkey
| | - Nesrin Kartal Ozer
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center (GEMHAM), Marmara University, 34854 Maltepe, Istanbul, Turkey.
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22
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Papandreou I, Verras M, McNeil B, Koong AC, Denko NC. Plant stilbenes induce endoplasmic reticulum stress and their anti-cancer activity can be enhanced by inhibitors of autophagy. Exp Cell Res 2015; 339:147-53. [PMID: 26477823 DOI: 10.1016/j.yexcr.2015.10.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 09/16/2015] [Accepted: 10/13/2015] [Indexed: 02/07/2023]
Abstract
BACKGROUND Environmental conditions or chemical agents can interfere with the function of the endoplasmic reticulum, and the resulting endoplasmic reticulum (ER) stress can be toxic to the cell if it is not relieved. The classical compensatory response to ER stress is the unfolded protein response (UPR) that reduces protein load in the ER. However, autophagy may also compensate by removing large insoluble protein aggregates. Agents that stress the ER can have anti-cancer activity, and novel applications of ER stress inducing agents are being investigated. Plant stilbenes are a class of stress responsive molecules that includes resveratrol, which are being investigated as potential therapeutics in humans for conditions such as aging or cancer. RESULTS We performed a screen of 1726 small, drug like molecules to identify those that could activate an ER-stress responsive luciferase gene. After secondary screening, we determined that the plant stilbenes pterostilbene and piceatannol were the most potent inducers of ER stress from this group. ER stress can be particularly toxic to cells with high ER load, so we examined their effect on cells expressing the Wnt family of secreted glycoprotein growth factors. Molecular analysis determined that these ER stress-inducing stilbenes could block Wnt processing and also induce autophagy in acute lymphoblastic leukemia cells expressing Wnt16. Combining pterostilbene (to induce ER stress) with chloroquine (to inhibit autophagy) lead to significant cellular toxicity in cells from aggressive acute lymphoblastic leukemia. CONCLUSIONS Plant stilbenes are potent inducers of ER stress. However, their toxicity is more pronounced in cancer cells expressing Wnt growth factors. The toxicity of stilbenes in these ALL cells can be potentiated by the addition of autophagy inhibitors, suggesting a possible therapeutic application.
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Affiliation(s)
- Ioanna Papandreou
- Department of Radiation Oncology, Wexner Medical Center and Comprehensive Cancer Center, Ohio State University, Columbus, OH 43210, USA.
| | - Meletios Verras
- Department of General Biology, University of Patras, Rio, Greece.
| | - Betina McNeil
- Department of Radiation Oncology, Wexner Medical Center and Comprehensive Cancer Center, Ohio State University, Columbus, OH 43210, USA.
| | - Albert C Koong
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Nicholas C Denko
- Department of Radiation Oncology, Wexner Medical Center and Comprehensive Cancer Center, Ohio State University, Columbus, OH 43210, USA.
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23
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Unfolded Protein Response Pathways in Neurodegenerative Diseases. J Mol Neurosci 2015; 57:529-37. [DOI: 10.1007/s12031-015-0633-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 07/28/2015] [Indexed: 12/14/2022]
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24
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Anelli T, Sannino S, Sitia R. Proteostasis and "redoxtasis" in the secretory pathway: Tales of tails from ERp44 and immunoglobulins. Free Radic Biol Med 2015; 83:323-30. [PMID: 25744412 DOI: 10.1016/j.freeradbiomed.2015.02.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 02/20/2015] [Accepted: 02/22/2015] [Indexed: 01/09/2023]
Abstract
In multicellular organisms, some cells are given the task of secreting huge quantities of proteins. To comply with their duty, they generally equip themselves with a highly developed endoplasmic reticulum (ER) and downstream organelles in the secretory pathway. These professional secretors face paramount proteostatic challenges in that they need to couple efficiency and fidelity in their secretory processes. On one hand, stringent quality control (QC) mechanisms operate from the ER onward to check the integrity of the secretome. On the other, the pressure to secrete can be overwhelming, as for instance on antibody-producing cells during infection. Maintaining homeostasis is particularly hard when the products to be released contain disulfide bonds, because oxidative folding entails production of reactive oxygen species. How are redox homeostasis ("redoxtasis") and proteostasis maintained despite the massive fluxes of cargo proteins traversing the pathway? Here we describe recent findings on how ERp44, a multifunctional chaperone of the secretory pathway, can modulate these processes integrating protein QC, redoxtasis, and calcium signaling.
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Affiliation(s)
- Tiziana Anelli
- Divisions of Genetics and Cell Biology, IRCCS Ospedale San Raffaele and Università Vita-Salute San Raffaele, 20132 Milan, Italy
| | - Sara Sannino
- Divisions of Genetics and Cell Biology, IRCCS Ospedale San Raffaele and Università Vita-Salute San Raffaele, 20132 Milan, Italy
| | - Roberto Sitia
- Divisions of Genetics and Cell Biology, IRCCS Ospedale San Raffaele and Università Vita-Salute San Raffaele, 20132 Milan, Italy.
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25
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Promotion of Endoplasmic Reticulum-Associated Degradation of Procathepsin D by Human Herpesvirus 8-Encoded Viral Interleukin-6. J Virol 2015; 89:7979-90. [PMID: 26018151 DOI: 10.1128/jvi.00375-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 05/15/2015] [Indexed: 01/08/2023] Open
Abstract
UNLABELLED The interleukin-6 homologue (viral interleukin-6 [vIL-6]) of human herpesvirus 8 is implicated in viral pathogenesis due to its proproliferative, inflammatory, and angiogenic properties, effected through gp130 receptor signaling. In primary effusion lymphoma (PEL) cells, vIL-6 is expressed latently and is essential for normal cell growth and viability. This is mediated partly via suppression of proapoptotic cathepsin D (CatD) via cocomplexing of the endoplasmic reticulum (ER)-localized CatD precursor, pro-CatD (pCatD), and vIL-6 with the previously uncharacterized ER membrane protein vitamin K epoxide reductase complex subunit 1 variant 2 (VKORC1v2). vIL-6 suppression of CatD occurs also during reactivated productive replication in PEL cells and is likely to contribute to proreplication functions of vIL-6. Here, we report that vIL-6 suppresses CatD through vIL-6, VKORC1v2, and pCatD association with components of the ER-associated degradation (ERAD) machinery. In transfected cells, expression of vIL-6 along with CatD led to proteasome-dependent (inhibitor-sensitive) decreases in CatD levels and the promotion of pCatD polyubiquitination. Depletion of particular ERAD-associated isomerases, lectins, and translocon components, including ERAD E3 ubiquitin ligase HRD1, diminished suppression of CatD by vIL-6. Coprecipitation assays identified direct or indirect interactions of VKORC1v2, vIL-6, and pCatD with translocon proteins (SEL1L and/or HRD1) and ERAD-associated lectins OS9 and XTP3-B. Endogenous CatD expression in PEL cells was increased by depletion of ERAD components, and suppression of CatD by vIL-6 overexpression in PEL cells was dependent on HRD1. Our data reveal a new mechanism of ER-localized vIL-6 activity and further characterize VKORC1v2 function. IMPORTANCE Human herpesvirus 8 (HHV-8) viral interleukin-6 (vIL-6), unlike cellular IL-6 proteins, is secreted inefficiently and sequestered mainly in the endoplasmic reticulum (ER), from where it can signal through the gp130 receptor. We have recently reported that vIL-6 also associates with a novel membrane protein termed vitamin K epoxide reductase complex subunit 1 variant 2 (VKORC1v2) and mediates suppression of VKORC1v2-cointeracting cathepsin D, a stress-released proapoptotic protein negatively impacting HHV-8 latently infected primary effusion lymphoma (PEL) cell viability and reactivated virus productive replication. Here, we have examined the mechanistic basis of the VKORC1v2-vIL-6 interaction-dependent suppression of cathepsin D and have found that this novel activity of vIL-6 is mediated through coassociation of VKORC1v2, procathepsin D, and vIL-6 with components of the ER-associated degradation (ERAD) machinery. Our findings provide information of significance for potential antiviral and therapeutic targeting of VKORC1v2-mediated vIL-6 activities and also indicate the nature of VKORC1v2 function in normal cell biology.
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26
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Michalak M, Gye MC. Endoplasmic reticulum stress in periimplantation embryos. Clin Exp Reprod Med 2015; 42:1-7. [PMID: 25874167 PMCID: PMC4390675 DOI: 10.5653/cerm.2015.42.1.1] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 12/18/2014] [Accepted: 12/24/2014] [Indexed: 01/04/2023] Open
Abstract
Stress coping mechanisms are critical to minimize or overcome damage caused by ever changing environmental conditions. They are designed to promote cell survival. The unfolded protein response (UPR) pathway is mobilized in response to the accumulation of unfolded proteins, ultimately in order to regain endoplasmic reticulum (ER) homeostasis. Various elements of coping responses to ER stress including Perk, Ask1, Bip, Chop, Gadd34, Ire1, Atf4, Atf6, and Xbp1 have been identified and were found to be inducible in oocytes and preimplantation embryos, suggesting that, as a normal part of the cellular adaptive mechanism, these coping responses, including the UPR, play a pivotal role in the development of preimplantation embryos. As such, the UPR-associated molecules and pathways may become useful markers for the potential diagnosis of stress conditions for preimplantation embryos. After implantation, ER stress-induced coping responses become physiologically important for a normal decidual response, placentation, and early organogenesis. Attenuation of ER stress coping responses by tauroursodeoxycholate and salubrinal was effective for prevention of cell death of cultured embryos. Further elucidation of new and relevant ER stress coping responses in periimplantation embryos might contribute to a comprehensive understanding of the regulation of normal development of embryonic development and potentiation of embryonic development in vitro.
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Affiliation(s)
- Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - Myung Chan Gye
- Department of Life Science and Institute of Natural Sciences, College of Natural Sciences, Hanyang University, Seoul, Korea
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27
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Merulla J, Soldà T, Molinari M. A novel UGGT1 and p97-dependent checkpoint for native ectodomains with ionizable intramembrane residue. Mol Biol Cell 2015; 26:1532-42. [PMID: 25694454 PMCID: PMC4395132 DOI: 10.1091/mbc.e14-12-1615] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 02/09/2015] [Indexed: 01/01/2023] Open
Abstract
There is unexpected collaboration of the cytosolic AAA-ATPase p97 and the luminal quality control factor UGGT1 in a novel, BiP- and CNX-independent protein quality checkpoint. This prevents Golgi transport of a chimera with a native ectodomain that passes the luminal quality control scrutiny but displays an intramembrane defect. Only native polypeptides are released from the endoplasmic reticulum (ER) to be transported at the site of activity. Persistently misfolded proteins are retained and eventually selected for ER-associated degradation (ERAD). The paradox of a structure-based protein quality control is that functional polypeptides may be destroyed if they are architecturally unfit. This has health-threatening implications, as shown by the numerous “loss-of-function” proteopathies, but also offers chances to intervene pharmacologically to promote bypassing of the quality control inspection and export of the mutant, yet functional protein. Here we challenged the ER of human cells with four modular glycopolypeptides designed to alert luminal and membrane protein quality checkpoints. Our analysis reveals the unexpected collaboration of the cytosolic AAA-ATPase p97 and the luminal quality control factor UDP-glucose:glycoprotein glucosyltransferase (UGGT1) in a novel, BiP- and CNX-independent checkpoint. This prevents Golgi transport of a chimera with a native ectodomain that passes the luminal quality control scrutiny but displays an intramembrane defect. Given that human proteopathies may result from impaired transport of functional polypeptides with minor structural defects, identification of quality checkpoints and treatments to bypass them as shown here upon silencing or pharmacologic inhibition of UGGT1 or p97 may have important clinical implications.
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Affiliation(s)
- Jessica Merulla
- Institute for Research in Biomedicine, Protein Folding and Quality Control, CH-6500 Bellinzona, Switzerland Università della Svizzera Italiana, CH-6900 Lugano, Switzerland Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3000 Bern, Switzerland
| | - Tatiana Soldà
- Institute for Research in Biomedicine, Protein Folding and Quality Control, CH-6500 Bellinzona, Switzerland Università della Svizzera Italiana, CH-6900 Lugano, Switzerland
| | - Maurizio Molinari
- Institute for Research in Biomedicine, Protein Folding and Quality Control, CH-6500 Bellinzona, Switzerland Università della Svizzera Italiana, CH-6900 Lugano, Switzerland Ecole Polytechnique Fédérale de Lausanne, School of Life Sciences, CH-1015 Lausanne, Switzerland
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28
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Sasaki K, Yoshida H. Organelle autoregulation-stress responses in the ER, Golgi, mitochondria and lysosome. J Biochem 2015; 157:185-95. [PMID: 25657091 DOI: 10.1093/jb/mvv010] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Organelle autoregulation is a homeostatic mechanism to regulate the capacity of each organelle according to cellular demands. The endoplasmic reticulum (ER) stress response increases the expression of ER chaperones and ER-associated degradation factors when the capacity of the ER becomes insufficient, e.g. during cellular differentiation or viral propagation, and which can be restored through increased synthesis of secretory or membrane proteins. In the Golgi stress response, insufficient organelle capacity is responded to by augmentation of glycosylation enzyme expression and vesicular transport components. The mitochondrial stress response upregulates mitochondrial chaperone and protease expression in the mitochondrial matrix and intermembrane space when unfolded proteins accumulate in the mitochondria. The lysosome stress response is activated during autophagy to enhance the function of the lysosome by transcriptional induction of lysosome genes including cathepsins. However, many of the molecular mechanisms of organelle autoregulation remain unclear. Here, we review recent discoveries in organelle autoregulation and their molecular mechanisms.
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Affiliation(s)
- Kanae Sasaki
- Department of Molecular Biochemistry, Graduate School of Life Science, University of Hyogo, Hyogo 678-1297, Japan
| | - Hiderou Yoshida
- Department of Molecular Biochemistry, Graduate School of Life Science, University of Hyogo, Hyogo 678-1297, Japan
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29
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Milhem RM, Al-Gazali L, Ali BR. Improved plasma membrane expression of the trafficking defective P344R mutant of muscle, skeletal, receptor tyrosine kinase (MuSK) causing congenital myasthenic syndrome. Int J Biochem Cell Biol 2015; 60:119-29. [PMID: 25562515 DOI: 10.1016/j.biocel.2014.12.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 12/14/2014] [Accepted: 12/22/2014] [Indexed: 02/08/2023]
Abstract
Muscle, skeletal, receptor tyrosine kinase (MuSK) is a key organizer at the postsynaptic membrane and critical for proper development and maintenance of the neuromuscular junction. Mutations in MUSK result in congenital myasthenic syndrome (CMS). We hypothesized that the CMS-causing missense mutation (P344R), found within the cysteine-rich domain of the protein, will affect its conformational tertiary structure. Consequently, the protein will misfold, get retained in the endoplasmic reticulum (ER) and lose its biological function through degradation by the highly conserved ER associated degradation (ERAD) machinery. We report that P344R-MuSK mutant is trafficking-deficient when expressed at 37°C in HeLa, COS-7 and HEK293 cell lines. It colocalized with the ER marker calnexin in contrast to wild-type MuSK which localized to the plasma membrane. The N-glycosylation status of P344R-MuSK is that of an immature and not properly post-translationally modified protein. Inhibition of protein synthesis showed that the P344R mutant's half-life is shorter than wild-type MuSK protein. Proteasomal inhibition resulted in the stabilization of the mutant protein. The mutant protein is highly ubiquitinated compared to wild-type confirming targeting for proteasomal degradation. The mutant showed around 50% of its in vivo autophosphorylation activity. P344R-MuSK mutant's trafficking defect is correctable by culturing the expressing cells at 27°C. Moreover, chemical compounds namely 2.5% glycerol, 1% dimethyl sulfoxide, 10 μM thapsigargin and 1 μM curcumin improved the maturation and exit of the mutant protein from the ER. These findings open perspectives for potential therapeutic intervention for patients with CMS harboring the P344R-MuSK mutation.
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Affiliation(s)
- Reham M Milhem
- Department of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates
| | - Lihadh Al-Gazali
- Department of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Bassam R Ali
- Department of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates.
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30
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Sozen E, Karademir B, Ozer NK. Basic mechanisms in endoplasmic reticulum stress and relation to cardiovascular diseases. Free Radic Biol Med 2015; 78:30-41. [PMID: 25452144 DOI: 10.1016/j.freeradbiomed.2014.09.031] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 09/03/2014] [Accepted: 09/26/2014] [Indexed: 01/30/2023]
Abstract
The folding process is an important step in protein synthesis for the functional shape or conformation of the protein. The endoplasmic reticulum (ER) is the main organelle for the correct folding procedure, which maintains the homeostasis of the organism. This process is normally well organized under unstressed conditions, whereas it may fail under oxidative and ER stress. The unfolded protein response (UPR) is a defense mechanism that removes the unfolded/misfolded proteins to prevent their accumulation, and two main degradation systems are involved in this defense, including the proteasome and autophagy. Cells decide which mechanism to use according to the type, severity, and duration of the stress. If the stress is too severe and in excess, the capacity of these degradation mechanisms, proteasomal degradation and autophagy, is not sufficient and the cell switches to apoptotic death. Because the accumulation of the improperly folded proteins leads to several diseases, it is important for the body to maintain this balance. Cardiovascular diseases are one of the important disorders related to failure of the UPR. Especially, protection mechanisms and the transition to apoptotic pathways have crucial roles in cardiac failure and should be highlighted in detailed studies to understand the mechanisms involved. This review is focused on the involvement of the proteasome, autophagy, and apoptosis in the UPR and the roles of these pathways in cardiovascular diseases.
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Affiliation(s)
- Erdi Sozen
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center, Marmara University, 34854 Maltepe, Istanbul, Turkey
| | - Betul Karademir
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center, Marmara University, 34854 Maltepe, Istanbul, Turkey
| | - Nesrin Kartal Ozer
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center, Marmara University, 34854 Maltepe, Istanbul, Turkey.
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31
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Arribas-González E, de Juan-Sanz J, Aragón C, López-Corcuera B. Molecular basis of the dominant negative effect of a glycine transporter 2 mutation associated with hyperekplexia. J Biol Chem 2014; 290:2150-65. [PMID: 25480793 DOI: 10.1074/jbc.m114.587055] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hyperekplexia or startle disease is a rare clinical syndrome characterized by an exaggerated startle in response to trivial tactile or acoustic stimuli. This neurological disorder can have serious consequences in neonates, provoking brain damage and/or sudden death due to apnea episodes and cardiorespiratory failure. Hyperekplexia is caused by defective inhibitory glycinergic neurotransmission. Mutations in the human SLC6A5 gene encoding the neuronal GlyT2 glycine transporter are responsible for the presynaptic form of the disease. GlyT2 mediates synaptic glycine recycling, which constitutes the main source of releasable transmitter at glycinergic synapses. Although the majority of GlyT2 mutations detected so far are recessive, a dominant negative mutant that affects GlyT2 trafficking does exist. In this study, we explore the properties and structural alterations of the S512R mutation in GlyT2. We analyze its dominant negative effect that retains wild-type GlyT2 in the endoplasmic reticulum (ER), preventing surface expression. We show that the presence of an arginine rather than serine 512 provoked transporter misfolding, enhanced association to the ER-chaperone calnexin, altered association with the coat-protein complex II component Sec24D, and thereby impeded ER exit. The S512R mutant formed oligomers with wild-type GlyT2 causing its retention in the ER. Overexpression of calnexin rescued wild-type GlyT2 from the dominant negative effect of the mutant, increasing the amount of transporter that reached the plasma membrane and dampening the interaction between the wild-type and mutant GlyT2. The ability of chemical chaperones to overcome the dominant negative effect of the disease mutation on the wild-type transporter was demonstrated in heterologous cells and primary neurons.
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Affiliation(s)
- Esther Arribas-González
- From the Departamento de Biología Molecular and Centro de Biología Molecular "Severo Ochoa," Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid 28049, Spain, the IdiPAZ-Hospital Universitario La Paz, Universidad Autónoma de Madrid, Madrid 28046, Spain
| | - Jaime de Juan-Sanz
- From the Departamento de Biología Molecular and Centro de Biología Molecular "Severo Ochoa," Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid 28049, Spain, the IdiPAZ-Hospital Universitario La Paz, Universidad Autónoma de Madrid, Madrid 28046, Spain the Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, Madrid 28029, Spain, and
| | - Carmen Aragón
- From the Departamento de Biología Molecular and Centro de Biología Molecular "Severo Ochoa," Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid 28049, Spain, the IdiPAZ-Hospital Universitario La Paz, Universidad Autónoma de Madrid, Madrid 28046, Spain the Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, Madrid 28029, Spain, and
| | - Beatriz López-Corcuera
- From the Departamento de Biología Molecular and Centro de Biología Molecular "Severo Ochoa," Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid 28049, Spain, the IdiPAZ-Hospital Universitario La Paz, Universidad Autónoma de Madrid, Madrid 28046, Spain the Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, Madrid 28029, Spain, and
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32
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Samuelson J, Robbins PW. Effects of N-glycan precursor length diversity on quality control of protein folding and on protein glycosylation. Semin Cell Dev Biol 2014; 41:121-8. [PMID: 25475176 DOI: 10.1016/j.semcdb.2014.11.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 11/24/2014] [Accepted: 11/26/2014] [Indexed: 01/24/2023]
Abstract
Asparagine-linked glycans (N-glycans) of medically important protists have much to tell us about the evolution of N-glycosylation and of N-glycan-dependent quality control (N-glycan QC) of protein folding in the endoplasmic reticulum. While host N-glycans are built upon a dolichol-pyrophosphate-linked precursor with 14 sugars (Glc3Man9GlcNAc2), protist N-glycan precursors vary from Glc3Man9GlcNAc2 (Acanthamoeba) to Man9GlcNAc2 (Trypanosoma) to Glc3Man5GlcNAc2 (Toxoplasma) to Man5GlcNAc2 (Entamoeba, Trichomonas, and Eimeria) to GlcNAc2 (Plasmodium and Giardia) to zero (Theileria). As related organisms have differing N-glycan lengths (e.g. Toxoplasma, Eimeria, Plasmodium, and Theileria), the present N-glycan variation is based upon secondary loss of Alg genes, which encode enzymes that add sugars to the N-glycan precursor. An N-glycan precursor with Man5GlcNAc2 is necessary but not sufficient for N-glycan QC, which is predicted by the presence of the UDP-glucose:glucosyltransferase (UGGT) plus calreticulin and/or calnexin. As many parasites lack glucose in their N-glycan precursor, UGGT product may be identified by inhibition of glucosidase II. The presence of an armless calnexin in Toxoplasma suggests secondary loss of N-glycan QC from coccidia. Positive selection for N-glycan sites occurs in secreted proteins of organisms with N-glycan QC and is based upon an increased likelihood of threonine but not serine in the +2 position versus asparagine. In contrast, there appears to be selection against N-glycan length in Plasmodium and N-glycan site density in Toxoplasma. Finally, there is suggestive evidence for N-glycan-dependent ERAD in Trichomonas, which glycosylates and degrades the exogenous reporter mutant carboxypeptidase Y (CPY*).
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Affiliation(s)
- John Samuelson
- Department of Molecular and Cell Biology, Boston University Goldman School of Dental Medicine, 72 East Concord St, Evans 425, Boston, MA 02118, USA.
| | - Phillips W Robbins
- Department of Molecular and Cell Biology, Boston University Goldman School of Dental Medicine, 72 East Concord St, Evans 425, Boston, MA 02118, USA.
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33
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The safety dance: biophysics of membrane protein folding and misfolding in a cellular context. Q Rev Biophys 2014; 48:1-34. [PMID: 25420508 DOI: 10.1017/s0033583514000110] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Most biological processes require the production and degradation of proteins, a task that weighs heavily on the cell. Mutations that compromise the conformational stability of proteins place both specific and general burdens on cellular protein homeostasis (proteostasis) in ways that contribute to numerous diseases. Efforts to elucidate the chain of molecular events responsible for diseases of protein folding address one of the foremost challenges in biomedical science. However, relatively little is known about the processes by which mutations prompt the misfolding of α-helical membrane proteins, which rely on an intricate network of cellular machinery to acquire and maintain their functional structures within cellular membranes. In this review, we summarize the current understanding of the physical principles that guide membrane protein biogenesis and folding in the context of mammalian cells. Additionally, we explore how pathogenic mutations that influence biogenesis may differ from those that disrupt folding and assembly, as well as how this may relate to disease mechanisms and therapeutic intervention. These perspectives indicate an imperative for the use of information from structural, cellular, and biochemical studies of membrane proteins in the design of novel therapeutics and in personalized medicine.
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34
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Benyair R, Ogen-Shtern N, Mazkereth N, Shai B, Ehrlich M, Lederkremer GZ. Mammalian ER mannosidase I resides in quality control vesicles, where it encounters its glycoprotein substrates. Mol Biol Cell 2014; 26:172-84. [PMID: 25411339 PMCID: PMC4294666 DOI: 10.1091/mbc.e14-06-1152] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
ER mannosidase I (ERManI) was found recently in the Golgi. This result is found to arise artificially from membrane disturbance in immunofluorescence methods. ERManI is located in novel vesicles to which substrates traffic and that converge at the ER-derived quality control compartment under ER stress. Endoplasmic reticulum α1,2 mannosidase I (ERManI), a central component of ER quality control and ER-associated degradation (ERAD), acts as a timer enzyme, modifying N-linked sugar chains of glycoproteins with time. This process halts glycoprotein folding attempts when necessary and targets terminally misfolded glycoproteins to ERAD. Despite the importance of ERManI in maintenance of glycoprotein quality control, fundamental questions regarding this enzyme remain controversial. One such question is the subcellular localization of ERManI, which has been suggested to localize to the ER membrane, the ER-derived quality control compartment (ERQC), and, surprisingly, recently to the Golgi apparatus. To try to clarify this controversy, we applied a series of approaches that indicate that ERManI is located, at the steady state, in quality control vesicles (QCVs) to which ERAD substrates are transported and in which they interact with the enzyme. Both endogenous and exogenously expressed ERManI migrate at an ER-like density on iodixanol gradients, suggesting that the QCVs are derived from the ER. The QCVs are highly mobile, displaying dynamics that are dependent on microtubules and COP-II but not on COP-I vesicle machinery. Under ER stress conditions, the QCVs converge in a juxtanuclear region, at the ERQC, as previously reported. Our results also suggest that ERManI is turned over by an active autophagic process. Of importance, we found that membrane disturbance, as is common in immunofluorescence methods, leads to an artificial appearance of ERManI in a Golgi pattern.
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Affiliation(s)
- Ron Benyair
- Department of Cell Research and Immunology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Navit Ogen-Shtern
- Department of Cell Research and Immunology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Niv Mazkereth
- Department of Cell Research and Immunology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ben Shai
- Department of Cell Research and Immunology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Marcelo Ehrlich
- Department of Cell Research and Immunology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Gerardo Z Lederkremer
- Department of Cell Research and Immunology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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35
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Fox RM, Andrew DJ. Transcriptional regulation of secretory capacity by bZip transcription factors. ACTA ACUST UNITED AC 2014; 10:28-51. [PMID: 25821458 PMCID: PMC4374484 DOI: 10.1007/s11515-014-1338-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Cells of specialized secretory organs expand their secretory pathways to accommodate the increased protein load necessary for their function. The endoplasmic reticulum (ER), the Golgi apparatus and the secretory vesicles, expand not only the membrane components but also the protein machinery required for increased protein production and transport. Increased protein load causes an ER stress response akin to the Unfolded Protein Response (UPR). Recent work has implicated several bZip transcription factors in the regulation of protein components of the early secretory pathway necessary to alleviate this stress. Here, we highlight eight bZip transcription factors in regulating secretory pathway component genes. These include components of the three canonical branches of the UPR-ATF4, XBP1, and ATF6, as well as the five members of the Creb3 family of transcription factors.We review findings from both invertebrate and vertebrate model systems suggesting that all of these proteins increase secretory capacity in response to increased protein load. Finally, we propose that the Creb3 family of factors may have a dual role in secretory cell differentiation by also regulating the pathways necessary for cell cycle exit during terminal differentiation.
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Affiliation(s)
- Rebecca M Fox
- The Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Deborah J Andrew
- The Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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36
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Suzuki T. The cytoplasmic peptide:N-glycanase (Ngly1)--basic science encounters a human genetic disorder. J Biochem 2014; 157:23-34. [DOI: 10.1093/jb/mvu068] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Hulleman JD, Kelly JW. Genetic ablation of N-linked glycosylation reveals two key folding pathways for R345W fibulin-3, a secreted protein associated with retinal degeneration. FASEB J 2014; 29:565-75. [PMID: 25389134 DOI: 10.1096/fj.14-255414] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An R345W mutation in the N-glycoprotein, fibulin-3 (F3), results in inefficient F3 folding/secretion and higher intracellular F3 levels. Inheritance of this mutation causes the retinal dystrophy malattia leventinese. N-Linked glycosylation is a common cotranslational protein modification that can regulate protein folding efficiency and energetics. Therefore, we explored how N-glycosylation alters the protein homeostasis or proteostasis of wild-type (WT) and R345W F3 in ARPE-19 cells. Enzymatic and lectin binding assays confirmed that WT and R345W F3 are both primarily N-glycosylated at Asn249. Tunicamycin treatment selectively reduced R345W F3 secretion by 87% (vs. WT F3). Genetic elimination of F3 N-glycosylation (via an N249Q mutation) caused R345W F3 to aggregate intracellularly and adopt an altered secreted conformation. The endoplasmic reticulum (ER) chaperones GRP78 (glucose-regulated protein 78) and GRP94 (glucose-regulated protein 94), and the ER lectins calnexin and calreticulin were identified as F3 binding partners by immunoprecipitation. Significantly more N249Q and N249Q/R345W F3 interacted with GRP94, while substantially less N249Q and N249Q/R345W interacted with the ER lectins than their N-glycosylated counterparts. Inhibition of GRP94 ATPase activity reduced only N249Q/R345W F3 secretion (by 62%), demonstrating this variant's unique reliance on GRP94 for secretion. These observations suggest that R345W F3, but not WT F3, requires N-glycosylation to acquire a stable, native-like structure.
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Affiliation(s)
- John D Hulleman
- Departments of Chemistry and the Skaggs Institute for Chemical Biology andMolecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Jeffery W Kelly
- Departments of Chemistry and the Skaggs Institute for Chemical Biology andMolecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California, USA
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Sharma M, Bhattacharyya S, Nain M, Kaur M, Sood V, Gupta V, Khasa R, Abdin MZ, Vrati S, Kalia M. Japanese encephalitis virus replication is negatively regulated by autophagy and occurs on LC3-I- and EDEM1-containing membranes. Autophagy 2014; 10:1637-51. [PMID: 25046112 DOI: 10.4161/auto.29455] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Autophagy is a lysosomal degradative pathway that has diverse physiological functions and plays crucial roles in several viral infections. Here we examine the role of autophagy in the life cycle of JEV, a neurotropic flavivirus. JEV infection leads to induction of autophagy in several cell types. JEV replication was significantly enhanced in neuronal cells where autophagy was rendered dysfunctional by ATG7 depletion, and in Atg5-deficient mouse embryonic fibroblasts (MEFs), resulting in higher viral titers. Autophagy was functional during early stages of infection however it becomes dysfunctional as infection progressed resulting in accumulation of misfolded proteins. Autophagy-deficient cells were highly susceptible to virus-induced cell death. We also observed JEV replication complexes that are marked by nonstructural protein 1 (NS1) and dsRNA colocalized with endogenous LC3 but not with GFP-LC3. Colocalization of NS1 and LC3 was also observed in Atg5 deficient MEFs, which contain only the nonlipidated form of LC3. Viral replication complexes furthermore show association with a marker of the ER-associated degradation (ERAD) pathway, EDEM1 (ER degradation enhancer, mannosidase α-like 1). Our data suggest that virus replication occurs on ERAD-derived EDEM1 and LC3-I-positive structures referred to as EDEMosomes. While silencing of ERAD regulators EDEM1 and SEL1L suppressed JEV replication, LC3 depletion exerted a profound inhibition with significantly reduced RNA levels and virus titers. Our study suggests that while autophagy is primarily antiviral for JEV and might have implications for disease progression and pathogenesis of JEV, nonlipidated LC3 plays an important autophagy independent function in the virus life cycle.
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Affiliation(s)
- Manish Sharma
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India; Department of Biotechnology; Faculty of Science; Jamia Hamdard; New Delhi, India
| | - Sankar Bhattacharyya
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India
| | - Minu Nain
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India; Department of Biotechnology; Faculty of Science; Jamia Hamdard; New Delhi, India
| | - Manpreet Kaur
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India
| | - Vikas Sood
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India
| | - Vishal Gupta
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India
| | - Renu Khasa
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India
| | - Malik Z Abdin
- Department of Biotechnology; Faculty of Science; Jamia Hamdard; New Delhi, India
| | - Sudhanshu Vrati
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India
| | - Manjula Kalia
- Vaccine and Infectious Disease Research Centre; Translational Health Science and Technology Institute; Gurgaon, Haryana India
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Byun H, Gou Y, Zook A, Lozano MM, Dudley JP. ERAD and how viruses exploit it. Front Microbiol 2014; 5:330. [PMID: 25071743 PMCID: PMC4080680 DOI: 10.3389/fmicb.2014.00330] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 06/16/2014] [Indexed: 01/09/2023] Open
Abstract
Endoplasmic reticulum (ER)-associated degradation (ERAD) is a universally important process among eukaryotic cells. ERAD is necessary to preserve cell integrity since the accumulation of defective proteins results in diseases associated with neurological dysfunction, cancer, and infections. This process involves recognition of misfolded or misassembled proteins that have been translated in association with ER membranes. Recognition of ERAD substrates leads to their extraction through the ER membrane (retrotranslocation or dislocation), ubiquitination, and destruction by cytosolic proteasomes. This review focuses on ERAD and its components as well as how viruses use this process to promote their replication and to avoid the immune response.
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Affiliation(s)
- Hyewon Byun
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
| | - Yongqiang Gou
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
| | - Adam Zook
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
| | - Mary M Lozano
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
| | - Jaquelin P Dudley
- Department of Molecular Biosciences, Center for Infectious Diseases and Institute for Cellular and Molecular Biology, The University of Texas at Austin Austin, TX, USA
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40
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Carpenter JE, Grose C. Varicella-zoster virus glycoprotein expression differentially induces the unfolded protein response in infected cells. Front Microbiol 2014; 5:322. [PMID: 25071735 PMCID: PMC4076746 DOI: 10.3389/fmicb.2014.00322] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 06/11/2014] [Indexed: 02/03/2023] Open
Abstract
Varicella-zoster virus (VZV) is a human herpesvirus that spreads to children as varicella or chicken pox. The virus then establishes latency in the nervous system and re-emerges, typically decades later, as zoster or shingles. We have reported previously that VZV induces autophagy in infected cells as well as exhibiting evidence of the Unfolded Protein Response (UPR): XBP1 splicing, a greatly expanded Endoplasmic Reticulum (ER) and CHOP expression. Herein we report the results of a UPR specific PCR array that measures the levels of mRNA of 84 different components of the UPR in VZV infected cells as compared to tunicamycin treated cells as a positive control and uninfected, untreated cells as a negative control. Tunicamycin is a mixture of chemicals that inhibits N-linked glycosylation in the ER with resultant protein misfolding and the UPR. We found that VZV differentially induces the UPR when compared to tunicamycin treatment. For example, tunicamycin treatment moderately increased (8-fold) roughly half of the array elements while downregulating only three (one ERAD and two FOLD components). VZV infection on the other hand upregulated 33 components including a little described stress sensor CREB-H (64-fold) as well as ER membrane components INSIG and gp78, which modulate cholesterol synthesis while downregulating over 20 components mostly associated with ERAD and FOLD. We hypothesize that this expression pattern is associated with an expanding ER with downregulation of active degradation by ERAD and apoptosis as the cell attempts to handle abundant viral glycoprotein synthesis.
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Affiliation(s)
- John E Carpenter
- Virology Laboratory, Department of Infectious Diseases, University of Iowa Children's Hospital Iowa City, IA, USA
| | - Charles Grose
- Virology Laboratory, Department of Infectious Diseases, University of Iowa Children's Hospital Iowa City, IA, USA
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41
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Nakatsukasa K, Kamura T, Brodsky JL. Recent technical developments in the study of ER-associated degradation. Curr Opin Cell Biol 2014; 29:82-91. [PMID: 24867671 DOI: 10.1016/j.ceb.2014.04.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 04/04/2014] [Accepted: 04/23/2014] [Indexed: 11/25/2022]
Abstract
Endoplasmic reticulum-associated degradation (ERAD) is a mechanism during which native and misfolded proteins are recognized and retrotranslocated across the ER membrane to the cytosol for degradation by the ubiquitin-proteasome system. Like other cellular pathways, the factors required for ERAD have been analyzed using both conventional genetic and biochemical approaches. More recently, however, an integrated top-down approach has identified a functional network that underlies the ERAD system. In turn, bottom-up reconstitution has become increasingly sophisticated and elucidated the molecular mechanisms underlying substrate recognition, ubiquitylation, retrotranslocation, and degradation. In addition, a live cell imaging technique and a site-specific in vivo photo-crosslinking approach have further dissected specific steps during ERAD. These technical developments have revealed an unexpected dynamicity of the membrane-associated ERAD complex. In this article, we will discuss how these technical developments have improved our understanding of the ERAD pathway and have led to new questions.
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Affiliation(s)
- Kunio Nakatsukasa
- Division of Biological Sciences, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan.
| | - Takumi Kamura
- Division of Biological Sciences, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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42
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Suzuki T, Harada Y. Non-lysosomal degradation pathway for N-linked glycans and dolichol-linked oligosaccharides. Biochem Biophys Res Commun 2014; 453:213-9. [PMID: 24866240 DOI: 10.1016/j.bbrc.2014.05.075] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 05/16/2014] [Indexed: 01/11/2023]
Abstract
There is growing evidence that asparagine (N)-linked glycans play pivotal roles in protein folding and intra- or intercellular trafficking of N-glycosylated proteins. During the N-glycosylation of proteins, significant amounts of free oligosaccharides (fOSs) and phosphorylated oligosaccharides (POSs) are generated at the endoplasmic reticulum (ER) membrane by unclarified mechanisms. fOSs are also formed in the cytosol by the enzymatic deglycosylation of misfolded glycoproteins destined for proteasomal degradation. This article summarizes the current knowledge of the molecular and regulatory mechanisms underlying the formation of fOSs and POSs in mammalian cells and Saccharomyces cerevisiae.
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Affiliation(s)
- Tadashi Suzuki
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center for Systems Chemical Biology, RIKEN Global Research Cluster, Japan.
| | - Yoichiro Harada
- Glycometabolome Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center for Systems Chemical Biology, RIKEN Global Research Cluster, Japan
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43
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van de Weijer ML, Bassik MC, Luteijn RD, Voorburg CM, Lohuis MAM, Kremmer E, Hoeben RC, LeProust EM, Chen S, Hoelen H, Ressing ME, Patena W, Weissman JS, McManus MT, Wiertz EJHJ, Lebbink RJ. A high-coverage shRNA screen identifies TMEM129 as an E3 ligase involved in ER-associated protein degradation. Nat Commun 2014; 5:3832. [PMID: 24807418 PMCID: PMC4024746 DOI: 10.1038/ncomms4832] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 04/08/2014] [Indexed: 01/05/2023] Open
Abstract
Misfolded ER proteins are retrotranslocated into the cytosol for degradation via the ubiquitin-proteasome system. The human cytomegalovirus protein US11 exploits this ER-associated protein degradation (ERAD) pathway to downregulate HLA class I molecules in virus-infected cells, thereby evading elimination by cytotoxic T-lymphocytes. US11-mediated degradation of HLA class I has been instrumental in the identification of key components of mammalian ERAD, including Derlin-1, p97, VIMP and SEL1L. Despite this, the process governing retrotranslocation of the substrate is still poorly understood. Here using a high-coverage genome-wide shRNA library, we identify the uncharacterized protein TMEM129 and the ubiquitin-conjugating E2 enzyme UBE2J2 to be essential for US11-mediated HLA class I downregulation. TMEM129 is an unconventional C4C4-type RING finger E3 ubiquitin ligase that resides within a complex containing various other ERAD components, including Derlin-1, Derlin-2, VIMP and p97, indicating that TMEM129 is an integral part of the ER-resident dislocation complex mediating US11-induced HLA class I degradation.
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Affiliation(s)
| | - Michael C Bassik
- 1] Department of Cellular and Molecular Pharmacology, California Institute for Quantitative Biomedical Research, Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA [2]
| | - Rutger D Luteijn
- Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands
| | - Cornelia M Voorburg
- Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands
| | - Mirjam A M Lohuis
- Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands
| | - Elisabeth Kremmer
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Molecular Immunology, 81377 Munich, Germany
| | - Rob C Hoeben
- Department of Molecular Cell Biology, Leiden University Medical Center, 2333ZC Leiden, The Netherlands
| | - Emily M LeProust
- 1] Genomics Solution Unit, Agilent Technologies Inc., Santa Clara, California 95051, USA [2]
| | - Siyuan Chen
- 1] Genomics Solution Unit, Agilent Technologies Inc., Santa Clara, California 95051, USA [2]
| | - Hanneke Hoelen
- Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands
| | - Maaike E Ressing
- 1] Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands [2] Department of Molecular Cell Biology, Leiden University Medical Center, 2333ZC Leiden, The Netherlands
| | - Weronika Patena
- 1] Department of Cellular and Molecular Pharmacology, California Institute for Quantitative Biomedical Research, Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA [2] Department of Microbiology and Immunology, University of California, San Francisco, California 94143, USA [3]
| | - Jonathan S Weissman
- Department of Cellular and Molecular Pharmacology, California Institute for Quantitative Biomedical Research, Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA
| | - Michael T McManus
- Department of Microbiology and Immunology, University of California, San Francisco, California 94143, USA
| | - Emmanuel J H J Wiertz
- 1] Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands [2]
| | - Robert Jan Lebbink
- 1] Medical Microbiology, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands [2]
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44
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Iannotti MJ, Figard L, Sokac AM, Sifers RN. A Golgi-localized mannosidase (MAN1B1) plays a non-enzymatic gatekeeper role in protein biosynthetic quality control. J Biol Chem 2014; 289:11844-11858. [PMID: 24627495 DOI: 10.1074/jbc.m114.552091] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Conformation-based disorders are manifested at the level of protein structure, necessitating an accurate understanding of how misfolded proteins are processed by the cellular proteostasis network. Asparagine-linked glycosylation plays important roles for protein quality control within the secretory pathway. The suspected role for the MAN1B1 gene product MAN1B1, also known as ER mannosidase I, is to function within the ER similar to the yeast ortholog Mns1p, which removes a terminal mannose unit to initiate a glycan-based ER-associated degradation (ERAD) signal. However, we recently discovered that MAN1B1 localizes to the Golgi complex in human cells and uncovered its participation in ERAD substrate retention, retrieval to the ER, and subsequent degradation from this organelle. The objective of the current study was to further characterize the contribution of MAN1B1 as part of a Golgi-based quality control network. Multiple lines of experimental evidence support a model in which neither the mannosidase activity nor catalytic domain is essential for the retention or degradation of the misfolded ERAD substrate Null Hong Kong. Instead, a highly conserved, vertebrate-specific non-enzymatic decapeptide sequence in the luminal stem domain plays a significant role in controlling the fate of overexpressed Null Hong Kong. Together, these findings define a new functional paradigm in which Golgi-localized MAN1B1 can play a mannosidase-independent gatekeeper role in the proteostasis network of higher eukaryotes.
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Affiliation(s)
- Michael J Iannotti
- Interdepartmental Program in Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030; Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas 77030
| | - Lauren Figard
- Interdepartmental Program in Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030; Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Anna M Sokac
- Interdepartmental Program in Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030; Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Richard N Sifers
- Interdepartmental Program in Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030; Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas 77030; Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas 77030; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030.
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45
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Aryal RP, Ju T, Cummings RD. Identification of a novel protein binding motif within the T-synthase for the molecular chaperone Cosmc. J Biol Chem 2014; 289:11630-11641. [PMID: 24616093 DOI: 10.1074/jbc.m114.555870] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Prior studies suggested that the core 1 β3-galactosyltransferase (T-synthase) is a specific client of the endoplasmic reticulum chaperone Cosmc, whose function is required for T-synthase folding, activity, and consequent synthesis of normal O-glycans in all vertebrate cells. To explore whether the T-synthase encodes a specific recognition motif for Cosmc, we used deletion mutagenesis to identify a cryptic linear and relatively hydrophobic peptide in the N-terminal stem region of the T-synthase that is essential for binding to Cosmc (Cosmc binding region within T-synthase, or CBRT). Using this sequence information, we synthesized a peptide containing CBRT and found that it directly interacts with Cosmc and also inhibits Cosmc-assisted in vitro refolding of denatured T-synthase. Moreover, engineered T-synthase carrying mutations within CBRT exhibited diminished binding to Cosmc that resulted in the formation of inactive T-synthase. To confirm the general recognition of CBRT by Cosmc, we performed a domain swap experiment in which we inserted the stem region of the T-synthase into the human β4GalT1 and found that the CBRT element can confer Cosmc binding onto the β4GalT1 chimera. Thus, CBRT is a unique recognition motif for Cosmc to promote its regulation and formation of active T-synthase and represents the first sequence-specific chaperone recognition system in the ER/Golgi required for normal protein O-glycosylation.
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Affiliation(s)
- Rajindra P Aryal
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Tongzhong Ju
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322.
| | - Richard D Cummings
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322.
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46
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Vishnu N, Jadoon Khan M, Karsten F, Groschner LN, Waldeck-Weiermair M, Rost R, Hallström S, Imamura H, Graier WF, Malli R. ATP increases within the lumen of the endoplasmic reticulum upon intracellular Ca2+ release. Mol Biol Cell 2014; 25:368-79. [PMID: 24307679 PMCID: PMC3907277 DOI: 10.1091/mbc.e13-07-0433] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 11/19/2013] [Accepted: 11/22/2013] [Indexed: 01/02/2023] Open
Abstract
Multiple functions of the endoplasmic reticulum (ER) essentially depend on ATP within this organelle. However, little is known about ER ATP dynamics and the regulation of ER ATP import. Here we describe real-time recordings of ER ATP fluxes in single cells using an ER-targeted, genetically encoded ATP sensor. In vitro experiments prove that the ATP sensor is both Ca(2+) and redox insensitive, which makes it possible to monitor Ca(2+)-coupled ER ATP dynamics specifically. The approach uncovers a cell type-specific regulation of ER ATP homeostasis in different cell types. Moreover, we show that intracellular Ca(2+) release is coupled to an increase of ATP within the ER. The Ca(2+)-coupled ER ATP increase is independent of the mode of Ca(2+) mobilization and controlled by the rate of ATP biosynthesis. Furthermore, the energy stress sensor, AMP-activated protein kinase, is essential for the ATP increase that occurs in response to Ca(2+) depletion of the organelle. Our data highlight a novel Ca(2+)-controlled process that supplies the ER with additional energy upon cell stimulation.
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Affiliation(s)
- Neelanjan Vishnu
- Institute of Molecular Biology and Biochemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Muhammad Jadoon Khan
- Institute of Molecular Biology and Biochemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Felix Karsten
- Institute of Molecular Biology and Biochemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Lukas N. Groschner
- Institute of Molecular Biology and Biochemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Markus Waldeck-Weiermair
- Institute of Molecular Biology and Biochemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Rene Rost
- Institute of Molecular Biology and Biochemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Seth Hallström
- Institute of Physiological Chemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Hiromi Imamura
- Precursory Research for Embryonic Science, Japan Science and Technology Agency, Tokyo 102-0075, Japan
| | - Wolfgang F. Graier
- Institute of Molecular Biology and Biochemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Roland Malli
- Institute of Molecular Biology and Biochemistry, Center of Physiological Medicine, Medical University of Graz, 8010 Graz, Austria
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47
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Bernasconi R, Galli C, Kokame K, Molinari M. Autoadaptive ER-associated degradation defines a preemptive unfolded protein response pathway. Mol Cell 2013; 52:783-93. [PMID: 24239290 DOI: 10.1016/j.molcel.2013.10.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 09/23/2013] [Accepted: 10/09/2013] [Indexed: 11/19/2022]
Abstract
Folding-defective proteins must be cleared efficiently from the endoplasmic reticulum (ER) to prevent perturbation of the folding environment and to maintain cellular proteostasis. Misfolded proteins engage dislocation machineries (dislocons) built around E3 ubiquitin ligases that promote their transport across the ER membrane, their polyubiquitylation, and their proteasomal degradation. Here, we report on the intrinsic instability of the HRD1 dislocon and the constitutive, rapid turnover of the scaffold protein HERP. We show that HRD1 dislocon integrity relies on the presence of HRD1 clients that interrupt, in a dose-dependent manner, the UBC6e/RNF5/p97/proteasome-controlled relay that controls HERP turnover. We propose that ER-associated degradation (ERAD) deploys autoadaptive regulatory pathways, collectively defined as ERAD tuning, to rapidly adapt degradation activity to misfolded protein load and to preempt the unfolded protein response (UPR) activation.
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Affiliation(s)
- Riccardo Bernasconi
- Institute for Research in Biomedicine, Protein Folding and Quality Control, 6500 Bellinzona, Switzerland
| | - Carmela Galli
- Institute for Research in Biomedicine, Protein Folding and Quality Control, 6500 Bellinzona, Switzerland
| | - Koichi Kokame
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Osaka 565-8565, Japan
| | - Maurizio Molinari
- Institute for Research in Biomedicine, Protein Folding and Quality Control, 6500 Bellinzona, Switzerland; Ecole Polytechnique Fédérale de Lausanne, School of Life Sciences, 1015 Lausanne, Switzerland.
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