1
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Michalak M. Calreticulin: Endoplasmic reticulum Ca 2+ gatekeeper. J Cell Mol Med 2023; 28:e17839. [PMID: 37424156 PMCID: PMC10902585 DOI: 10.1111/jcmm.17839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 06/21/2023] [Accepted: 06/27/2023] [Indexed: 07/11/2023] Open
Abstract
Endoplasmic reticulum (ER) luminal Ca2+ is vital for the function of the ER and regulates many cellular processes. Calreticulin is a highly conserved, ER-resident Ca2+ binding protein and lectin-like chaperone. Over four decades of studying calreticulin demonstrate that this protein plays a crucial role in maintaining Ca2+ supply under different physiological conditions, in managing access to Ca2+ and how Ca2+ is used depending on the environmental events and in making sure that Ca2+ is not misused. Calreticulin plays a role of ER luminal Ca2+ sensor to manage Ca2+ -dependent ER luminal events including maintaining interaction with its partners, Ca2+ handling molecules, substrates and stress sensors. The protein is strategically positioned in the lumen of the ER from where the protein manages access to and distribution of Ca2+ for many cellular Ca2+ -signalling events. The importance of calreticulin Ca2+ pool extends beyond the ER and includes influence of cellular processes involved in many aspects of cellular pathophysiology. Abnormal handling of the ER Ca2+ contributes to many pathologies from heart failure to neurodegeneration and metabolic diseases.
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Affiliation(s)
- Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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2
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Zhang J, Li X, Wang X, Guan W. Transcriptome analysis of two bloom-forming Prorocentrum species reveals physiological changes related to light and temperature. HARMFUL ALGAE 2023; 125:102421. [PMID: 37220974 DOI: 10.1016/j.hal.2023.102421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 02/25/2023] [Accepted: 03/05/2023] [Indexed: 05/25/2023]
Abstract
Temperature and light substantially influence red tide succession. However, it remains unclear whether the molecular mechanisms differ among species. In this study, we measured the variation in the physiological parameters of growth and pigments and transcriptional levels of two bloom-forming dinoflagellates, namely Prorocentrum micans and P. cordatum. This was undertaken in four treatments that represented two factorial temperature combinations (LT: 20 °C, HT: 28 °C) and light conditions (LL: 50 µmol photons m-2 s-1, HL: 400 µmol photons m-2 s-1) for 7-day batch culture. Growth under high temperature and high light (HTHL) was the fastest, while growth under high temperature and low light (HTLL) was the slowest. The pigments (chlorophyll a and carotenoids) decreased significantly in all high light (HL) treatments, but not in high temperature (HT) treatments. HL alleviated the low light-caused photolimitation and enhanced the growth of both species at low temperatures. However, HT inhibited the growth of both species by inducing oxidative stress under low light conditions. HL mitigated the HT-induced stress on growth in both species by upregulating photosynthesis, antioxidase activity, protein folding, and degradation. The cells of P. micans were more sensitive to HT and HL than those of P. cordatum. This study deepens our understanding of the species-specific mechanism of dinoflagellates at the transcriptomic level, adapting to the future ocean changes including higher solar radiation and higher temperatures in the upper mixed layer.
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Affiliation(s)
- Jiazhu Zhang
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Xuanwen Li
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Xinjie Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Wanchun Guan
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
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3
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Sen Santara S, Lee DJ, Crespo Â, Hu JJ, Walker C, Ma X, Zhang Y, Chowdhury S, Meza-Sosa KF, Lewandrowski M, Zhang H, Rowe M, McClelland A, Wu H, Junqueira C, Lieberman J. The NK cell receptor NKp46 recognizes ecto-calreticulin on ER-stressed cells. Nature 2023; 616:348-356. [PMID: 37020026 PMCID: PMC10165876 DOI: 10.1038/s41586-023-05912-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 03/02/2023] [Indexed: 04/07/2023]
Abstract
Natural killer (NK) cell kill infected, transformed and stressed cells when an activating NK cell receptor is triggered1. Most NK cells and some innate lymphoid cells express the activating receptor NKp46, encoded by NCR1, the most evolutionarily ancient NK cell receptor2,3. Blockage of NKp46 inhibits NK killing of many cancer targets4. Although a few infectious NKp46 ligands have been identified, the endogenous NKp46 cell surface ligand is unknown. Here we show that NKp46 recognizes externalized calreticulin (ecto-CRT), which translocates from the endoplasmic reticulum (ER) to the cell membrane during ER stress. ER stress and ecto-CRT are hallmarks of chemotherapy-induced immunogenic cell death5,6, flavivirus infection and senescence. NKp46 recognition of the P domain of ecto-CRT triggers NK cell signalling and NKp46 caps with ecto-CRT in NK immune synapses. NKp46-mediated killing is inhibited by knockout or knockdown of CALR, the gene encoding CRT, or CRT antibodies, and is enhanced by ectopic expression of glycosylphosphatidylinositol-anchored CRT. NCR1)-deficient human (and Nrc1-deficient mouse) NK cells are impaired in the killing of ZIKV-infected, ER-stressed and senescent cells and ecto-CRT-expressing cancer cells. Importantly, NKp46 recognition of ecto-CRT controls mouse B16 melanoma and RAS-driven lung cancers and enhances tumour-infiltrating NK cell degranulation and cytokine secretion. Thus, NKp46 recognition of ecto-CRT as a danger-associated molecular pattern eliminates ER-stressed cells.
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Affiliation(s)
- Sumit Sen Santara
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, India
| | - Dian-Jang Lee
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Ângela Crespo
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Jun Jacob Hu
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Caitlin Walker
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Xiyu Ma
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Ying Zhang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Sourav Chowdhury
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Karla F Meza-Sosa
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
- Laboratorio de Neuroinmunobiología, Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Mercedes Lewandrowski
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Haiwei Zhang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Marjorie Rowe
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Arthur McClelland
- Center for Nanoscale Systems, Faculty of Arts and Sciences, Harvard University, Cambridge, MA, USA
| | - Hao Wu
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Caroline Junqueira
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA.
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA.
- Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Brazil.
| | - Judy Lieberman
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA.
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA.
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4
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Esperante D, Flisser A, Mendlovic F. The many faces of parasite calreticulin. Front Immunol 2023; 14:1101390. [PMID: 36993959 PMCID: PMC10040973 DOI: 10.3389/fimmu.2023.1101390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/23/2023] [Indexed: 03/16/2023] Open
Abstract
Calreticulin from parasites and its vertebrate hosts share ~50% identity and many of its functions are equally conserved. However, the existing amino acid differences can affect its biological performance. Calreticulin plays an important role in Ca2+ homeostasis and as a chaperone involved in the correct folding of proteins within the endoplasmic reticulum. Outside the endoplasmic reticulum, calreticulin is involved in several immunological functions such as complement inhibition, enhancement of efferocytosis, and immune upregulation or inhibition. Several parasite calreticulins have been shown to limit immune responses and promote infectivity, while others are strong immunogens and have been used for the development of potential vaccines that limit parasite growth. Furthermore, calreticulin is essential in the dialogue between parasites and hosts, inducing Th1, Th2 or regulatory responses in a species-specific manner. In addition, calreticulin participates as initiator of endoplasmic reticulum stress in tumor cells and promotion of immunogenic cell death and removal by macrophages. Direct anti-tumoral activity has also been reported. The highly immunogenic and pleiotropic nature of parasite calreticulins, either as positive or negative regulators of the immune response, render these proteins as valuable tools to modulate immunopathologies and autoimmune disorders, as well as a potential treatment of neoplasms. Moreover, the disparities in the amino acid composition of parasite calreticulins might provide subtle variations in the mechanisms of action that could provide advantages as therapeutic tools. Here, we review the immunological roles of parasite calreticulins and discuss possible beneficial applications.
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Affiliation(s)
- Diego Esperante
- Plan de Estudios Combinados en Medicina (PECEM), Facultad de Medicine, Universidad Nacional Autonóma de México (UNAM), Mexico City, Mexico
| | - Ana Flisser
- Plan de Estudios Combinados en Medicina (PECEM), Facultad de Medicine, Universidad Nacional Autonóma de México (UNAM), Mexico City, Mexico
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autonóma de México (UNAM), Mexico City, Mexico
| | - Fela Mendlovic
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autonóma de México (UNAM), Mexico City, Mexico
- Facultad de Ciencias de la Salud, Universidad Anahuac Mexico Norte, Huixquilucan, Mexico
- *Correspondence: Fela Mendlovic,
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5
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Calnexin, More Than Just a Molecular Chaperone. Cells 2023; 12:cells12030403. [PMID: 36766745 PMCID: PMC9913998 DOI: 10.3390/cells12030403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 01/17/2023] [Accepted: 01/17/2023] [Indexed: 01/26/2023] Open
Abstract
Calnexin is a type I integral endoplasmic reticulum (ER) membrane protein with an N-terminal domain that resides in the lumen of the ER and a C-terminal domain that extends into the cytosol. Calnexin is commonly referred to as a molecular chaperone involved in the folding and quality control of membrane-associated and secreted proteins, a function that is attributed to its ER- localized domain with a structure that bears a strong resemblance to another luminal ER chaperone and Ca2+-binding protein known as calreticulin. Studies have discovered that the cytosolic C-terminal domain of calnexin undergoes distinct post-translational modifications and interacts with a variety of proteins. Here, we discuss recent findings and hypothesize that the post-translational modifications of the calnexin C-terminal domain and its interaction with specific cytosolic proteins play a role in coordinating ER functions with events taking place in the cytosol and other cellular compartments.
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6
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Mamidi AS, Surolia A. Mixed mechanism of conformational selection and induced fit as a molecular recognition process in the calreticulin family of proteins. PLoS Comput Biol 2022; 18:e1010661. [PMID: 36508460 PMCID: PMC9744295 DOI: 10.1371/journal.pcbi.1010661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 10/17/2022] [Indexed: 12/14/2022] Open
Abstract
The fundamental question on the mechanism of molecular recognition during ligand binding has attracted a lot of scientific scrutiny. The two competing theories of ligand binding-"induced fit" and "conformational selection" have been proposed to explain biomolecular recognition. Since exploring a family of proteins with similar structural architectures and conserved functional roles can provide valuable insight into the significance of molecular structure and function, we performed molecular dynamics simulations on the calreticulin family of proteins, which specifically recognize monoglucosylated N-glycan during the protein folding process. Atomistic simulations of lectins in free and bound forms demonstrated that they exist in several conformations spanning from favorable to unfavorable for glycan binding. Our analysis was confined to the carbohydrate recognition domain (CRD) of these lectins to demonstrate the degree of conservation in protein sequence and structure and relate them with their function. Furthermore, we computed the lectin-glycan binding affinity using the mmPBSA approach to identify the most favorable lectin conformation for glycan binding and compared the molecular interaction fields in terms of noncovalent bond interactions. We also demonstrated the involvement of Tyr and Trp residues in the CRD with the non-reducing end glucose and central mannose residues, which contribute to some of the specific interactions. Furthermore, we analyzed the conformational changes in the CRD through SASA, RMSFs and protein surface topography mapping of electrostatic and hydrophobic potentials. Our findings demonstrate a hybrid mechanism of molecular recognition, initially driven by conformational selection followed by glycan-induced fluctuations in the key residues to strengthen the glycan binding interactions.
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Affiliation(s)
| | - Avadhesha Surolia
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore–India
- * E-mail: (ASM); (AS)
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7
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Calreticulin mutations affect its chaperone function and perturb the glycoproteome. Cell Rep 2022; 41:111689. [DOI: 10.1016/j.celrep.2022.111689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 07/17/2022] [Accepted: 10/27/2022] [Indexed: 11/23/2022] Open
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8
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Sakono M. ER Endogenous Protein Complexed with Lectin Chaperones Calnexin/Calreticulin. TRENDS GLYCOSCI GLYC 2022. [DOI: 10.4052/tigg.2119.1e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Masafumi Sakono
- Department of Applied Chemistry, Faculty of Engineering, University of Toyama
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9
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Sakono M. ER Endogenous Protein Complexed with Lectin Chaperones Calnexin/Calreticulin. TRENDS GLYCOSCI GLYC 2022. [DOI: 10.4052/tigg.2119.1j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Masafumi Sakono
- Department of Applied Chemistry, Faculty of Engineering, University of Toyama
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10
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Takeda Y, Kikuma T. UDP-glucose:Glycoprotein Glucosyltransferase–Selenof Complex: A Potential Glycoprotein-folding Machine. TRENDS GLYCOSCI GLYC 2022. [DOI: 10.4052/tigg.2118.1j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Yoichi Takeda
- Department of Biotechnology, College of Life Sciences, Ritsumeikan University
| | - Takashi Kikuma
- Department of Biotechnology, College of Life Sciences, Ritsumeikan University
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11
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Takeda Y, Kikuma T. UDP-glucose:Glycoprotein Glucosyltransferase–Selenof Complex: A Potential Glycoprotein-folding Machine. TRENDS GLYCOSCI GLYC 2022. [DOI: 10.4052/tigg.2118.1e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Yoichi Takeda
- Department of Biotechnology, College of Life Sciences, Ritsumeikan University
| | - Takashi Kikuma
- Department of Biotechnology, College of Life Sciences, Ritsumeikan University
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12
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Chambers JE, Zubkov N, Kubánková M, Nixon-Abell J, Mela I, Abreu S, Schwiening M, Lavarda G, López-Duarte I, Dickens JA, Torres T, Kaminski CF, Holt LJ, Avezov E, Huntington JA, George-Hyslop PS, Kuimova MK, Marciniak SJ. Z-α 1-antitrypsin polymers impose molecular filtration in the endoplasmic reticulum after undergoing phase transition to a solid state. SCIENCE ADVANCES 2022; 8:eabm2094. [PMID: 35394846 PMCID: PMC8993113 DOI: 10.1126/sciadv.abm2094] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 02/16/2022] [Indexed: 05/06/2023]
Abstract
Misfolding of secretory proteins in the endoplasmic reticulum (ER) features in many human diseases. In α1-antitrypsin deficiency, the pathogenic Z variant aberrantly assembles into polymers in the hepatocyte ER, leading to cirrhosis. We show that α1-antitrypsin polymers undergo a liquid:solid phase transition, forming a protein matrix that retards mobility of ER proteins by size-dependent molecular filtration. The Z-α1-antitrypsin phase transition is promoted during ER stress by an ATF6-mediated unfolded protein response. Furthermore, the ER chaperone calreticulin promotes Z-α1-antitrypsin solidification and increases protein matrix stiffness. Single-particle tracking reveals that solidification initiates in cells with normal ER morphology, previously assumed to represent a healthy pool. We show that Z-α1-antitrypsin-induced hypersensitivity to ER stress can be explained by immobilization of ER chaperones within the polymer matrix. This previously unidentified mechanism of ER dysfunction provides a template for understanding a diverse group of related proteinopathies and identifies ER chaperones as potential therapeutic targets.
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Affiliation(s)
- Joseph E. Chambers
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Nikita Zubkov
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Markéta Kubánková
- Department of Chemistry, Imperial College London, Wood Lane, London W12 0BZ, UK
| | - Jonathon Nixon-Abell
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Ioanna Mela
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, UK
| | - Susana Abreu
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Max Schwiening
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Giulia Lavarda
- Departamento de Química Orgánica and Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Madrid 28049, Spain
| | - Ismael López-Duarte
- Departamento de Química Orgánica and Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Madrid 28049, Spain
| | - Jennifer A. Dickens
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Tomás Torres
- Departamento de Química Orgánica and Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Madrid 28049, Spain
- IMDEA Nanociencia, Campus de Cantoblanco, Madrid 28049, Spain
| | - Clemens F. Kaminski
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, UK
| | - Liam J. Holt
- Institute for Systems Genetics, New York University Grossman School of Medicine, 435 E 30th St, New York, NY 10016, USA
| | - Edward Avezov
- Department of Clinical Neurosciences and UK Dementia Research Institute, University of Cambridge, Cambridge CB2 0AH, UK
| | - James A. Huntington
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - Peter St George-Hyslop
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
- Department of Medicine (Neurology), Temerty Faculty of Medicine, University of Toronto, University Health Network, Toronto, ON M5T 0S8, Canada
- Taub Institute For Research on Alzheimer’s Disease and the Ageing Brain, Department of Neurology, Columbia University Irvine Medical Center, 630 West 1/68 Street, New York, NY 10032, USA
| | - Marina K. Kuimova
- Department of Chemistry, Imperial College London, Wood Lane, London W12 0BZ, UK
| | - Stefan J. Marciniak
- Cambridge Institute for Medical Research (CIMR), Department of Medicine, University of Cambridge, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
- Royal Papworth Hospital, Cambridge CB2 0AY, UK
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13
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Fan F, Zhang Q, Zhang Y, Huang G, Liang X, Wang CC, Wang L, Lu D. Two protein disulfide isomerase subgroups work synergistically in catalyzing oxidative protein folding. PLANT PHYSIOLOGY 2022; 188:241-254. [PMID: 34609517 PMCID: PMC8774737 DOI: 10.1093/plphys/kiab457] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 08/31/2021] [Indexed: 05/13/2023]
Abstract
Disulfide bonds play essential roles in the folding of secretory and plasma membrane proteins in the endoplasmic reticulum (ER). In eukaryotes, protein disulfide isomerase (PDI) is an enzyme catalyzing the disulfide bond formation and isomerization in substrates. The Arabidopsis (Arabidopsis thaliana) genome encodes diverse PDIs including structurally distinct subgroups PDI-L and PDI-M/S. It remains unclear how these AtPDIs function to catalyze the correct disulfide formation. We found that one Arabidopsis ER oxidoreductin-1 (Ero1), AtERO1, can interact with multiple PDIs. PDI-L members AtPDI2/5/6 mainly serve as an isomerase, while PDI-M/S members AtPDI9/10/11 are more efficient in accepting oxidizing equivalents from AtERO1 and catalyzing disulfide bond formation. Accordingly, the pdi9/10/11 triple mutant exhibited much stronger inhibition than pdi1/2/5/6 quadruple mutant under dithiothreitol treatment, which caused disruption of disulfide bonds in plant proteins. Furthermore, AtPDI2/5 work synergistically with PDI-M/S members in relaying disulfide bonds from AtERO1 to substrates. Our findings reveal the distinct but overlapping roles played by two structurally different AtPDI subgroups in oxidative protein folding in the ER.
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Affiliation(s)
- Fenggui Fan
- State Key Laboratory of Plant Genomics, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education & College of Life Sciences, Northwest University, Xi'an, 710069, China
| | - Qiao Zhang
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Shijiazhuang 050024, China
| | - Yini Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guozhong Huang
- State Key Laboratory of Plant Genomics, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Xuelian Liang
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Shijiazhuang 050024, China
| | - Chih-chen Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lei Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dongping Lu
- State Key Laboratory of Plant Genomics, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
- Hebei Collaboration Innovation Center for Cell Signaling, Hebei Normal University, Shijiazhuang 050024, China
- Author for communication:
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14
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Zhou Y, Fan F, Han Y, Lu D. Arabidopsis PDI11 interacts with lectin molecular chaperons calreticulin 1 and 2 through its D domain. Biochem Biophys Res Commun 2022; 588:55-60. [PMID: 34952470 DOI: 10.1016/j.bbrc.2021.12.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 12/14/2021] [Indexed: 02/07/2023]
Abstract
The endoplasmic reticulum (ER) is equipped with protein disulfide isomerases (PDIs), molecular chaperons, and other folding enzymes to ensure that newly synthesized proteins in the ER are properly folded. Molecular chaperons and PDIs can form complex to promote protein folding in the ER of mammalian cells. In plants, many PDIs associate with each other and function cooperatively in oxidative protein folding. As a plant unique protein disulfide isomerase, Arabidopsis thaliana PDI11 (AtPDI11) demonstrates oxidative protein folding activities and works synergistically with AtPDI2/5. However, whether AtPDI11 associates with molecular chaperons or AtPDIs in catalyzing disulfide formation remained unknown. Here, we find that AtPDI11 interacts with ER resident lectin chaperones calreticulin 1 (CRT1) and CRT2. Furthermore, the D domain, but not the a or a' domain of AtPDI11 provides the biding sites for its interaction with CRT1/2. Moreover, the P domain of CRT1 is responsible for its interaction with AtPDI11. Our work implies that Arabidopsis CRT1/2 may specifically recruit AtPDI11 to assist the folding of glycoproteins in the ER.
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Affiliation(s)
- Yuanyuan Zhou
- State Key Laboratory of Plant Genomics, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei, 050021, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Fenggui Fan
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education & College of Life Sciences, Northwest University, Xi'an, Shaanxi, 710069, China
| | - Yongfeng Han
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, 050024, Shijiazhuang, China.
| | - Dongping Lu
- State Key Laboratory of Plant Genomics, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei, 050021, China.
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15
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Impact of Calreticulin and Its Mutants on Endoplasmic Reticulum Function in Health and Disease. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2021. [PMID: 34050866 DOI: 10.1007/978-3-030-67696-4_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/03/2024]
Abstract
The endoplasmic reticulum (ER) performs key cellular functions including protein synthesis, lipid metabolism and signaling. While these functions are spatially isolated in structurally distinct regions of the ER, there is cross-talk between the pathways. One vital player that is involved in ER function is the ER-resident protein calreticulin (CALR). It is a calcium ion-dependent lectin chaperone that primarily assists in glycoprotein synthesis in the ER as part of the protein quality control machinery. CALR also buffers calcium ion release and mediates other glycan-independent protein interactions. Mutations in CALR have been reported in a subset of chronic blood tumors called myeloproliferative neoplasms. The mutations consist of insertions or deletions in the CALR gene that all cause a + 1 bp shift in the reading frame and lead to a dramatic alteration of the amino acid sequence of the C-terminal domain of CALR. This alters CALR function and affects cell homeostasis. This chapter will discuss how CALR and mutant CALR affect ER health and disease.
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16
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Ninagawa S. N-glycan Dependent Protein Quality Control System in the Endoplasmic Reticulum. TRENDS GLYCOSCI GLYC 2021. [DOI: 10.4052/tigg.2108.2e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Satoshi Ninagawa
- Department of Biophysics, Graduate School of Science, Kyoto University
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17
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Ninagawa S. N-glycan Dependent Protein Quality Control System in the Endoplasmic Reticulum. TRENDS GLYCOSCI GLYC 2021. [DOI: 10.4052/tigg.2108.2j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Satoshi Ninagawa
- Department of Biophysics, Graduate School of Science, Kyoto University
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18
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Marinko JT, Wright MT, Schlebach JP, Clowes KR, Heintzman DR, Plate L, Sanders CR. Glycosylation limits forward trafficking of the tetraspan membrane protein PMP22. J Biol Chem 2021; 296:100719. [PMID: 33933451 PMCID: PMC8191293 DOI: 10.1016/j.jbc.2021.100719] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 04/20/2021] [Accepted: 04/27/2021] [Indexed: 02/01/2023] Open
Abstract
Peripheral myelin protein 22 (PMP22) folds and trafficks inefficiently, with only 20% of newly expressed protein trafficking to the cell surface. This behavior is exacerbated in many of the mutants associated with Charcot–Marie–Tooth disease, motivating further study. Here we characterized the role of N-glycosylation in limiting PMP22 trafficking. We first eliminated N-glycosylation using an N41Q mutation, which resulted in an almost 3-fold increase in trafficking efficiency of wildtype (WT) PMP22 and a 10-fold increase for the severely unstable L16P disease mutant in HEK293 cells, with similar results in Schwann cells. Total cellular levels were also much higher for the WT/N41Q mutant, although not for the L16P/N41Q form. Depletion of oligosaccharyltransferase OST-A and OST-B subunits revealed that WT PMP22 is N-glycosylated posttranslationally by OST-B, whereas L16P is cotranslationally glycosylated by OST-A. Quantitative proteomic screens revealed similarities and differences in the interactome for WT, glycosylation-deficient, and unstable mutant forms of PMP22 and also suggested that L16P is sequestered at earlier stages of endoplasmic reticulum quality control. CRISPR knockout studies revealed a role for retention in endoplasmic reticulum sorting receptor 1 (RER1) in limiting the trafficking of all three forms, for UDP-glucose glycoprotein glucosyltransferase 1 (UGGT1) in limiting the trafficking of WT and L16P but not N41Q, and calnexin (CNX) in limiting the trafficking of WT and N41Q but not L16P. This work shows that N-glycosylation is a limiting factor to forward trafficking PMP22 and sheds light on the proteins involved in its quality control.
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Affiliation(s)
- Justin T Marinko
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA; Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Madison T Wright
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA
| | | | - Katherine R Clowes
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA; Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Darren R Heintzman
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University, Nashville, Tennessee, USA
| | - Lars Plate
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA; Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Charles R Sanders
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA; Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA.
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19
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Ishikawa Y, Taga Y, Zientek K, Mizuno N, Salo AM, Semenova O, Tufa SF, Keene DR, Holden P, Mizuno K, Gould DB, Myllyharju J, Bächinger HP. Type I and type V procollagen triple helix uses different subsets of the molecular ensemble for lysine posttranslational modifications in the rER. J Biol Chem 2021; 296:100453. [PMID: 33631195 PMCID: PMC7988497 DOI: 10.1016/j.jbc.2021.100453] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 02/12/2021] [Accepted: 02/19/2021] [Indexed: 11/25/2022] Open
Abstract
Collagen is the most abundant protein in humans. It has a characteristic triple-helix structure and is heavily posttranslationally modified. The complex biosynthesis of collagen involves processing by many enzymes and chaperones in the rough endoplasmic reticulum. Lysyl hydroxylase 1 (LH1) is required to hydroxylate lysine for cross-linking and carbohydrate attachment within collagen triple helical sequences. Additionally, a recent study of prolyl 3-hydroxylase 3 (P3H3) demonstrated that this enzyme may be critical for LH1 activity; however, the details surrounding its involvement remain unclear. If P3H3 is an LH1 chaperone that is critical for LH1 activity, P3H3 and LH1 null mice should display a similar deficiency in lysyl hydroxylation. To test this hypothesis, we compared the amount and location of hydroxylysine in the triple helical domains of type V and I collagen from P3H3 null, LH1 null, and wild-type mice. The amount of hydroxylysine in type V collagen was reduced in P3H3 null mice, but surprisingly type V collagen from LH1 null mice contained as much hydroxylysine as type V collagen from wild-type mice. In type I collagen, our results indicate that LH1 plays a global enzymatic role in lysyl hydroxylation. P3H3 is also involved in lysyl hydroxylation, particularly at cross-link formation sites, but is not required for all lysyl hydroxylation sites. In summary, our study suggests that LH1 and P3H3 likely have two distinct mechanisms to recognize different collagen types and to distinguish cross-link formation sites from other sites in type I collagen.
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Affiliation(s)
- Yoshihiro Ishikawa
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon, USA; Research Department, Shriners Hospital for Children, Portland, Oregon, USA; Department of Ophthalmology, University of California San Francisco, School of Medicine, San Francisco, California, USA.
| | - Yuki Taga
- Nippi Research Institute of Biomatrix, Ibaraki, Japan
| | - Keith Zientek
- Research Department, Shriners Hospital for Children, Portland, Oregon, USA
| | - Nobuyo Mizuno
- Research Department, Shriners Hospital for Children, Portland, Oregon, USA
| | - Antti M Salo
- Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Olesya Semenova
- Research Department, Shriners Hospital for Children, Portland, Oregon, USA
| | - Sara F Tufa
- Research Department, Shriners Hospital for Children, Portland, Oregon, USA
| | - Douglas R Keene
- Research Department, Shriners Hospital for Children, Portland, Oregon, USA
| | - Paul Holden
- Research Department, Shriners Hospital for Children, Portland, Oregon, USA
| | | | - Douglas B Gould
- Department of Ophthalmology, University of California San Francisco, School of Medicine, San Francisco, California, USA; Department of Anatomy, University of California, San Francisco, School of Medicine, San Francisco, California USA
| | - Johanna Myllyharju
- Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Hans Peter Bächinger
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon, USA
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20
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Roles of Calreticulin in Protein Folding, Immunity, Calcium Signaling and Cell Transformation. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2021; 59:145-162. [PMID: 34050865 DOI: 10.1007/978-3-030-67696-4_7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The endoplasmic reticulum (ER) is an organelle that mediates the proper folding and assembly of proteins destined for the cell surface, the extracellular space and subcellular compartments such as the lysosomes. The ER contains a wide range of molecular chaperones to handle the folding requirements of a diverse set of proteins that traffic through this compartment. The lectin-like chaperones calreticulin and calnexin are an important class of structurally-related chaperones relevant for the folding and assembly of many N-linked glycoproteins. Despite the conserved mechanism of action of these two chaperones in nascent protein recognition and folding, calreticulin has unique functions in cellular calcium signaling and in the immune response. The ER-related functions of calreticulin in the assembly of major histocompatibility complex (MHC) class I molecules are well-studied and provide many insights into the modes of substrate and co-chaperone recognition by calreticulin. Calreticulin is also detectable on the cell surface under some conditions, where it induces the phagocytosis of apoptotic cells. Furthermore, mutations of calreticulin induce cell transformation in myeloproliferative neoplasms (MPN). Studies of the functions of the mutant calreticulin in cell transformation and immunity have provided many insights into the normal biology of calreticulin, which are discussed.
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21
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The Role of Endoplasmic Reticulum Chaperones in Protein Folding and Quality Control. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2021; 59:27-50. [PMID: 34050861 DOI: 10.1007/978-3-030-67696-4_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Molecular chaperones assist the folding of nascent chains in the cell. Chaperones also aid in quality control decisions as persistent chaperone binding can help to sort terminal misfolded proteins for degradation. There are two major molecular chaperone families in the endoplasmic reticulum (ER) that assist proteins in reaching their native structure and evaluating the fidelity of the maturation process. The ER Hsp70 chaperone, BiP, supports adenine nucleotide-regulated binding to non-native proteins that possess exposed hydrophobic regions. In contrast, the carbohydrate-dependent chaperone system involving the membrane protein calnexin and its soluble paralogue calreticulin recognize a specific glycoform of an exposed hydrophilic protein modification for which the composition is controlled by a series of glycosidases and transferases. Here, we compare and contrast the properties, mechanisms of action and functions of these different chaperones systems that work in parallel, as well as together, to assist a large variety of substrates that traverse the eukaryotic secretory pathway.
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22
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Structural Analysis of Calreticulin, an Endoplasmic Reticulum-Resident Molecular Chaperone. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2021; 59:13-25. [PMID: 34050860 DOI: 10.1007/978-3-030-67696-4_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Calreticulin (Calr) is an endoplasmic reticulum (ER) chaperone involved in protein quality control, Ca2+ regulation and other cellular processes. The structure of Calr is unusual, reflecting different functions of the protein: a proline-rich β-hairpin arm and an acidic C-terminal tail protrude from a globular core, composed of a β-sheet sandwich and an α-helix. The arm and tail interact in the presence of Ca2+ and cover the upper β-sheet, where a carbohydrate-binding site gives the chaperone glycoprotein affinity. At the edge of the carbohydrate-binding site is a conserved, strained disulphide bridge, formed between C106 and C137 of human Calr, which lies in a polypeptide-binding site. The lower β-sheet has several conserved residues, comprised of a characteristic triad, D166-H170-D187, Tyr172 and the free C163. In addition to its role in the ER, Calr translocates to the cell surface upon stress and functions as an immune surveillance marker. In some myeloproliferative neoplasms, the acidic Ca2+-binding C-terminal tail is transformed into a polybasic sequence.
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23
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Nakao H, Seko A, Ito Y, Sakono M. Dimerization of ER-resident molecular chaperones mediated by ERp29. Biochem Biophys Res Commun 2020; 536:52-58. [PMID: 33360823 DOI: 10.1016/j.bbrc.2020.12.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 12/08/2020] [Indexed: 11/30/2022]
Abstract
The lectin chaperones calnexin (CNX) and calreticulin (CRT) localized in the endoplasmic reticulum play important roles in glycoprotein quality control. Although the interaction between these lectin chaperones and ERp57 is well known, it has been recently reported that endoplasmic reticulum protein 29 (ERp29), a member of PDI family, interacts with CNX and CRT. The biochemical function of ERp29 is unclear because it exhibits no ERp57-like redox activity. In this study, we addressed the possibility that ER chaperones CNX and CRT are connected via ERp29, based on our observation that ERp29 exists as a dimer. As a result, we showed that CNX dimerizes through ERp29. These results endorse the hypothesis that ERp29 serves as a bridge that links two molecules of CNX. Also, we showed that similar complexes such as CNX-CRT were formed via ERp29.
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Affiliation(s)
- Hitomi Nakao
- Department of Applied Chemistry, University of Toyama 3190 Gofuku, Toyama, 930-855, Japan
| | - Akira Seko
- Japan Science and Technology Agency (JST), ERATO Ito Glycotrilogy Project, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Yukishige Ito
- Japan Science and Technology Agency (JST), ERATO Ito Glycotrilogy Project, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan; RIKEN Cluster for Pioneering Research 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan; Graduate School of Science, Osaka University Machikaneyama 1-1 Toyonaka, Osaka, 560-0043, Japan
| | - Masafumi Sakono
- Department of Applied Chemistry, University of Toyama 3190 Gofuku, Toyama, 930-855, Japan.
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24
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Rellmann Y, Eidhof E, Dreier R. Review: ER stress-induced cell death in osteoarthritic cartilage. Cell Signal 2020; 78:109880. [PMID: 33307190 DOI: 10.1016/j.cellsig.2020.109880] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/03/2020] [Accepted: 12/04/2020] [Indexed: 12/16/2022]
Abstract
In cartilage, chondrocytes are responsible for the biogenesis and maintenance of the extracellular matrix (ECM) composed of proteins, glycoproteins and proteoglycans. Various cellular stresses, such as hypoxia, nutrient deprivation, oxidative stress or the accumulation of advanced glycation end products (AGEs) during aging, but also translational errors or mutations in cartilage components or chaperone proteins affect the synthesis and secretion of ECM proteins, causing protein aggregates to accumulate in the endoplasmic reticulum (ER). This condition, referred to as ER stress, interferes with cartilage cell homeostasis and initiates the unfolded protein response (UPR), a rescue mechanism to regain cell viability and function. Chronic or irreversible ER stress, however, triggers UPR-initiated cell death. Due to unresolved ER stress in chondrocytes, diseases of the skeletal system, such as chondrodysplasias, arise. ER stress has also been identified as a contributing factor to the pathogenesis of cartilage degeneration processes such as osteoarthritis (OA). This review provides current knowledge about the biogenesis of ECM components in chondrocytes, describes possible causes for the impairment of involved processes and focuses on the ER stress-induced cell death in articular cartilage during OA. Targeting of the ER stress itself or intervention in UPR signaling to reduce death of chondrocytes may be promising for future osteoarthritis therapy.
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Affiliation(s)
- Yvonne Rellmann
- Institute of Physiological Chemistry and Pathobiochemistry, Waldeyerstraße 15, 48149 Münster, Germany
| | - Elco Eidhof
- Institute of Physiological Chemistry and Pathobiochemistry, Waldeyerstraße 15, 48149 Münster, Germany
| | - Rita Dreier
- Institute of Physiological Chemistry and Pathobiochemistry, Waldeyerstraße 15, 48149 Münster, Germany.
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25
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Kuribara T, Totani K. Structural insights into N-linked glycan-mediated protein folding from chemical and biological perspectives. Curr Opin Struct Biol 2020; 68:41-47. [PMID: 33296772 DOI: 10.1016/j.sbi.2020.11.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/26/2020] [Accepted: 11/02/2020] [Indexed: 11/26/2022]
Abstract
About half of all newly synthesized proteins have N-linked glycans. These glycans play pivotal roles in controlling the folding, sorting, and degradation of glycoproteins via several glycan-related proteins. The glycan-mediated protein quality control system is important for cellular homeostasis. In this review, we summarize recent advances in our understanding of the system and discuss structural insights from chemical and biological perspectives. In particular, we focus on the mechanisms by which these mediators respond to several folding states of glycoproteins.
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Affiliation(s)
- Taiki Kuribara
- Seikei University, 3-3-1 Kichijoji-kitamachi, Musashino-shi, Tokyo 180-8633, Japan
| | - Kiichiro Totani
- Seikei University, 3-3-1 Kichijoji-kitamachi, Musashino-shi, Tokyo 180-8633, Japan.
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26
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Glycan dependent refolding activity of ER glucosyltransferase (UGGT). Biochim Biophys Acta Gen Subj 2020; 1864:129709. [DOI: 10.1016/j.bbagen.2020.129709] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 08/13/2020] [Accepted: 08/14/2020] [Indexed: 01/21/2023]
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27
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Ito Y, Kajihara Y, Takeda Y. Chemical‐Synthesis‐Based Approach to Glycoprotein Functions in the Endoplasmic Reticulum. Chemistry 2020; 26:15461-15470. [DOI: 10.1002/chem.202004158] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Indexed: 12/18/2022]
Affiliation(s)
- Yukishige Ito
- Project Research Center for Fundamental Sciences Graduate School of Science Osaka University Toyonaka Osaka 5600043 Japan
- RIKEN Cluster for Pioneering Research Wako Saitama 3510198 Japan
| | - Yasuhiro Kajihara
- Project Research Center for Fundamental Sciences Graduate School of Science Osaka University Toyonaka Osaka 5600043 Japan
- Department of Chemistry Graduate School of Science Osaka University Toyonaka Osaka 5600043 Japan
| | - Yoichi Takeda
- Department of Biotechnology Ritsumeikan University Kusatsu Shiga 5258577 Japan
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28
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Kozlov G, Gehring K. Calnexin cycle - structural features of the ER chaperone system. FEBS J 2020; 287:4322-4340. [PMID: 32285592 PMCID: PMC7687155 DOI: 10.1111/febs.15330] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/31/2020] [Accepted: 04/08/2020] [Indexed: 12/21/2022]
Abstract
The endoplasmic reticulum (ER) is the major folding compartment for secreted and membrane proteins and is the site of a specific chaperone system, the calnexin cycle, for folding N-glycosylated proteins. Recent structures of components of the calnexin cycle have deepened our understanding of quality control mechanisms and protein folding pathways in the ER. In the calnexin cycle, proteins carrying monoglucosylated glycans bind to the lectin chaperones calnexin and calreticulin, which recruit a variety of function-specific chaperones to mediate protein disulfide formation, proline isomerization, and general protein folding. Upon trimming by glucosidase II, the glycan without an inner glucose residue is no longer able to bind to the lectin chaperones. For proteins that have not yet folded properly, the enzyme UDP-glucose:glycoprotein glucosyltransferase (UGGT) acts as a checkpoint by adding a glucose back to the N-glycan. This allows the misfolded proteins to re-associate with calnexin and calreticulin for additional rounds of chaperone-mediated refolding and prevents them from exiting the ERs. Here, we review progress in structural studies of the calnexin cycle, which reveal common features of how lectin chaperones recruit function-specific chaperones and how UGGT recognizes misfolded proteins.
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Affiliation(s)
- Guennadi Kozlov
- From the Department of Biochemistry & Centre for Structural BiologyMcGill UniversityMontréalQCCanada
| | - Kalle Gehring
- From the Department of Biochemistry & Centre for Structural BiologyMcGill UniversityMontréalQCCanada
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29
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Guo XY, Liu YS, Gao XD, Kinoshita T, Fujita M. Calnexin mediates the maturation of GPI-anchors through ER retention. J Biol Chem 2020; 295:16393-16410. [PMID: 32967966 DOI: 10.1074/jbc.ra120.015577] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/05/2020] [Indexed: 01/05/2023] Open
Abstract
The protein folding and lipid moiety status of glycosylphosphatidylinositol-anchored proteins (GPI-APs) are monitored in the endoplasmic reticulum (ER), with calnexin playing dual roles in the maturation of GPI-APs. In the present study, we investigated the functions of calnexin in the quality control and lipid remodeling of GPI-APs in the ER. By directly binding the N-glycan on proteins, calnexin was observed to efficiently retain GPI-APs in the ER until they were correctly folded. In addition, sufficient ER retention time was crucial for GPI-inositol deacylation, which is mediated by post-GPI attachment protein 1 (PGAP1). Once the calnexin/calreticulin cycle was disrupted, misfolded and inositol-acylated GPI-APs could not be retained in the ER and were exposed on the plasma membrane. In calnexin/calreticulin-deficient cells, endogenous GPI-anchored alkaline phosphatase was expressed on the cell surface, but its activity was significantly decreased. ER stress induced surface expression of misfolded GPI-APs, but proper GPI-inositol deacylation occurred due to the extended time that they were retained in the ER. Our results indicate that calnexin-mediated ER quality control systems for GPI-APs are necessary for both protein folding and GPI-inositol deacylation.
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Affiliation(s)
- Xin-Yu Guo
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Yi-Shi Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Xiao-Dong Gao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Taroh Kinoshita
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, Japan
| | - Morihisa Fujita
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China.
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Silva-Palacios A, Zazueta C, Pedraza-Chaverri J. ER membranes associated with mitochondria: Possible therapeutic targets in heart-associated diseases. Pharmacol Res 2020; 156:104758. [PMID: 32200027 DOI: 10.1016/j.phrs.2020.104758] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 02/06/2020] [Accepted: 03/16/2020] [Indexed: 12/14/2022]
Abstract
Cardiovascular system cell biology is tightly regulated and mitochondria play a relevant role in maintaining heart function. In recent decades, associations between such organelles and the sarco/endoplasmic reticulum (SR) have been raised great interest. Formally identified as mitochondria-associated SR membranes (MAMs), these structures regulate different cellular functions, including calcium management, lipid metabolism, autophagy, oxidative stress, and management of unfolded proteins. In this review, we highlight MAMs' alterations mainly in cardiomyocytes, linked with cardiovascular diseases, such as cardiac ischemia-reperfusion, heart failure, and dilated cardiomyopathy. We also describe proteins that are part of the MAMs' machinery, as the FUN14 domain containing 1 (FUNDC1), the sigma 1 receptor (Sig-1R) and others, which might be new molecular targets to preserve the function and structure of the heart in such diseases. Understanding the machinery of MAMs and its function demands our attention, as such knowledge might contribute to strengthen the role of these relative novel structures in heart diseases.
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Affiliation(s)
- Alejandro Silva-Palacios
- Department of Cardiovascular Biomedicine, National Institute of Cardiology-Ignacio Chávez, Mexico City, Mexico.
| | - Cecilia Zazueta
- Department of Cardiovascular Biomedicine, National Institute of Cardiology-Ignacio Chávez, Mexico City, Mexico
| | - José Pedraza-Chaverri
- Department of Biology, Faculty of Chemistry, National Autonomous University of Mexico, Circuito Exterior S/N, C. U., 04510, Mexico City, Mexico.
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31
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Abstract
The site of protein folding and maturation for the majority of proteins that are secreted, localized to the plasma membrane or targeted to endomembrane compartments is the endoplasmic reticulum (ER). It is essential that proteins targeted to the ER are properly folded in order to carry out their function, as well as maintain protein homeostasis, as accumulation of misfolded proteins could lead to the formation of cytotoxic aggregates. Because protein folding is an error-prone process, the ER contains protein quality control networks that act to optimize proper folding and trafficking of client proteins. If a protein is unable to reach its native state, it is targeted for ER retention and subsequent degradation. The protein quality control networks of the ER that oversee this evaluation or interrogation process that decides the fate of maturing nascent chains is comprised of three general types of families: the classical chaperones, the carbohydrate-dependent system, and the thiol-dependent system. The cooperative action of these families promotes protein quality control and protein homeostasis in the ER. This review will describe the families of the ER protein quality control network and discuss the functions of individual members.
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32
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Ihara Y, Ikezaki M, Takatani M, Ito Y. Calnexin/Calreticulin and Assays Related to N-Glycoprotein Folding In Vitro. Methods Mol Biol 2020; 2132:295-308. [PMID: 32306337 DOI: 10.1007/978-1-0716-0430-4_29] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Calnexin (CNX) and calreticulin (CRT) are ER-resident lectin-like molecular chaperones involved in the quality control of secretory or membrane glycoproteins. They can exert molecular chaperone functions via specific binding to the early processing intermediates of Glc1Man9GlcNAc2 oligosaccharides of N-glycoproteins. CNX and CRT have similar N-terminal luminal domains and share the same jelly roll tertiary structure as legume lectins. In addition to the lectin-like interactions, CNX and CRT also suppress the aggregation of non-glycosylated substrates through interaction with hydrophobic peptide parts, suggesting a general chaperone function in glycan-dependent and glycan-independent manners. This chapter describes the isolation and purification of CRT produced in a bacterial expression system. We also introduce in vitro assays to estimate the molecular chaperone functions of CRT via the interaction with monoglucosylated N-glycans using Jack bean α-mannosidase as a target substrate. These assays are valuable in assessing quality control events related to the CNX/CRT chaperone cycle and lectin functions.
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Affiliation(s)
- Yoshito Ihara
- Department of Biochemistry, Wakayama Medical University, Wakayama, Japan.
| | - Midori Ikezaki
- Department of Biochemistry, Wakayama Medical University, Wakayama, Japan
| | - Maki Takatani
- Synthetic Cellular Chemistry Laboratory, RIKEN, Saitama, Japan
| | - Yukishige Ito
- Synthetic Cellular Chemistry Laboratory, RIKEN, Saitama, Japan
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Adams BM, Ke H, Gierasch LM, Gershenson A, Hebert DN. Proper secretion of the serpin antithrombin relies strictly on thiol-dependent quality control. J Biol Chem 2019; 294:18992-19011. [PMID: 31662433 DOI: 10.1074/jbc.ra119.010450] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/24/2019] [Indexed: 01/04/2023] Open
Abstract
The protein quality control machinery of the endoplasmic reticulum (ERQC) ensures that client proteins are properly folded. ERQC substrates may be recognized as nonnative by the presence of exposed hydrophobic surfaces, free thiols, or processed N-glycans. How these features dictate which ERQC pathways engage a given substrate is poorly understood. Here, using metabolic labeling, immunoprecipitations, various biochemical assays, and the human serpin antithrombin III (ATIII) as a model, we explored the role of ERQC systems in mammalian cells. Although ATIII has N-glycans and a hydrophobic core, we found that its quality control depended solely on free thiol content. Mutagenesis of all six Cys residues in ATIII to Ala resulted in its efficient secretion even though the product was not natively folded. ATIII variants with free thiols were retained in the endoplasmic reticulum but not degraded. These results provide insight into the hierarchy of ERQC systems and reveal a fundamental vulnerability of ERQC in a case of reliance on the thiol-dependent quality control pathway.
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Affiliation(s)
- Benjamin M Adams
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003.,Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Massachusetts 01003
| | - Haiping Ke
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003
| | - Lila M Gierasch
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003.,Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Massachusetts 01003.,Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Anne Gershenson
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003.,Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Massachusetts 01003
| | - Daniel N Hebert
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003 .,Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Massachusetts 01003
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Needham PG, Guerriero CJ, Brodsky JL. Chaperoning Endoplasmic Reticulum-Associated Degradation (ERAD) and Protein Conformational Diseases. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a033928. [PMID: 30670468 DOI: 10.1101/cshperspect.a033928] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Misfolded proteins compromise cellular homeostasis. This is especially problematic in the endoplasmic reticulum (ER), which is a high-capacity protein-folding compartment and whose function requires stringent protein quality-control systems. Multiprotein complexes in the ER are able to identify, remove, ubiquitinate, and deliver misfolded proteins to the 26S proteasome for degradation in the cytosol, and these events are collectively termed ER-associated degradation, or ERAD. Several steps in the ERAD pathway are facilitated by molecular chaperone networks, and the importance of ERAD is highlighted by the fact that this pathway is linked to numerous protein conformational diseases. In this review, we discuss the factors that constitute the ERAD machinery and detail how each step in the pathway occurs. We then highlight the underlying pathophysiology of protein conformational diseases associated with ERAD.
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Affiliation(s)
- Patrick G Needham
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | | | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
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Matsusaki M, Kanemura S, Kinoshita M, Lee YH, Inaba K, Okumura M. The Protein Disulfide Isomerase Family: from proteostasis to pathogenesis. Biochim Biophys Acta Gen Subj 2019; 1864:129338. [PMID: 30986509 DOI: 10.1016/j.bbagen.2019.04.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 03/08/2019] [Accepted: 04/02/2019] [Indexed: 12/13/2022]
Abstract
In mammalian cells, nearly one-third of proteins are inserted into the endoplasmic reticulum (ER), where they undergo oxidative folding and chaperoning assisted by approximately 20 members of the protein disulfide isomerase family (PDIs). PDIs consist of multiple thioredoxin-like domains and recognize a wide variety of proteins via highly conserved interdomain flexibility. Although PDIs have been studied intensely for almost 50 years, exactly how they maintain protein homeostasis in the ER remains unknown, and is important not only for fundamental biological understanding but also for protein misfolding- and aggregation-related pathophysiology. Herein, we review recent advances in structural biology and biophysical approaches that explore the underlying mechanism by which PDIs fulfil their distinct functions to promote productive protein folding and scavenge misfolded proteins in the ER, the primary factory for efficient production of the secretome.
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Affiliation(s)
- Motonori Matsusaki
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Aramaki aza Aoba 6-3, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Shingo Kanemura
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Aramaki aza Aoba 6-3, Aoba-ku, Sendai, Miyagi 980-8578, Japan; School of Science and Technology, Kwansei Gakuin University, Gakuen 2-1, Sanda, Hyogo 669-1337, Japan
| | - Misaki Kinoshita
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Aramaki aza Aoba 6-3, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Young-Ho Lee
- Protein Structure Group, Korea Basic Science Institute, Ochang, Chungbuk 28199, South Korea; Bio-Analytical Science, University of Science and Technology, Daejeon 34113, South Korea
| | - Kenji Inaba
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, Miyagi 980-8577, Japan.
| | - Masaki Okumura
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Aramaki aza Aoba 6-3, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
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Trowitzsch S, Tampé R. ABC Transporters in Dynamic Macromolecular Assemblies. J Mol Biol 2018; 430:4481-4495. [DOI: 10.1016/j.jmb.2018.07.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 07/24/2018] [Accepted: 07/30/2018] [Indexed: 12/28/2022]
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Abstract
The endoplasmic reticulum (ER) is the site of maturation for roughly one-third of all cellular proteins. ER-resident molecular chaperones and folding catalysts promote folding and assembly in a diverse set of newly synthesized proteins. Because these processes are error-prone, all eukaryotic cells have a quality-control system in place that constantly monitors the proteins and decides their fate. Proteins with potentially harmful nonnative conformations are subjected to assisted folding or degraded. Persistent folding-defective proteins are distinguished from folding intermediates and targeted for degradation by a specific process involving clearance from the ER. Although the basic principles of these processes appear conserved from yeast to animals and plants, there are distinct differences in the ER-associated degradation of misfolded glycoproteins. The general importance of ER quality-control events is underscored by their involvement in the biogenesis of diverse cell surface receptors and their crucial maintenance of protein homeostasis under diverse stress conditions.
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Affiliation(s)
- Richard Strasser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, 1190 Vienna, Austria;
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Characterization of the oxidative protein folding activity of a unique plant oxidoreductase, Arabidopsis protein disulfide isomerase-11. Biochem Biophys Res Commun 2018; 495:1041-1047. [DOI: 10.1016/j.bbrc.2017.11.111] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 11/17/2017] [Indexed: 11/19/2022]
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Satoh T, Kato K. Structural Aspects of ER Glycoprotein Quality-Control System Mediated by Glucose Tagging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1104:149-169. [PMID: 30484248 DOI: 10.1007/978-981-13-2158-0_8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
N-linked oligosaccharides attached to proteins act as tags for glycoprotein quality control, ensuring their appropriate folding and trafficking in cells. Interactions with a variety of intracellular lectins determine glycoprotein fates. Monoglucosylated glycoforms are the hallmarks of incompletely folded glycoproteins in the protein quality-control system, in which glucosidase II and UDP-glucose/glycoprotein glucosyltransferase are, respectively, responsible for glucose trimming and attachment. In this review, we summarize a recently emerging view of the structural basis of the functional mechanisms of these key enzymes as well as substrate N-linked oligosaccharides exhibiting flexible structures, as revealed by applying a series of biophysical techniques including small-angle X-ray scattering, X-ray crystallography, high-speed atomic force microscopy , electron microscopy , and computational simulation in conjunction with NMR spectroscopy.
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Affiliation(s)
- Tadashi Satoh
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, Japan
| | - Koichi Kato
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, Japan. .,Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, Okazaki, Aichi, Japan.
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