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Hua F, Bonzerato CG, Keller KR, Guo D, Luo J, Wojcikiewicz RJH. The erlin1/erlin2 complex binds to and stabilizes phosphatidylinositol 3-phosphate and regulates autophagy. Biochem Biophys Res Commun 2024; 731:150397. [PMID: 39018973 DOI: 10.1016/j.bbrc.2024.150397] [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: 06/17/2024] [Revised: 06/25/2024] [Accepted: 07/11/2024] [Indexed: 07/19/2024]
Abstract
The erlin1/erlin2 (E1/E2) complex is an endoplasmic reticulum membrane-located assemblage of the proteins erlin1 and erlin2. Here, we demonstrate direct and selective binding of phosphatidylinositol 3-phosphate (PI(3)P) to recombinant erlins and that disruption or deletion of the E1/E2 complex reduces HeLa cell PI(3)P levels by ∼50 %. This reduction correlated with a decrease in autophagic flux, with no effect on the endocytic pathway, and was not due to reduced VPS34 kinase activity, which is critical for maintaining steady-state PI(3)P levels. Pharmacological inhibition of VPS34 and suppression of PI(3)P levels caused a similar reduction in autophagic flux. Overall, these data indicate that by binding to PI(3)P, the E1/E2 complex plays an important role in maintaining the steady-state levels of PI(3)P and, thus, sustains some key PI(3)P-dependent processes, e.g., autophagy.
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Affiliation(s)
- Fanghui Hua
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA
| | - Caden G Bonzerato
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA
| | - Katherine R Keller
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA
| | - Dandan Guo
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA
| | - Juntao Luo
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, 13210, USA
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2
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Cogan G, Zaki MS, Issa M, Keren B, Guillaud-Bataille M, Renaldo F, Isapof A, Lallemant P, Stevanin G, Guillot-Noel L, Courtin T, Buratti J, Freihuber C, Gleeson JG, Howarth R, Durr A, de Sainte Agathe JM, Mignot C. Biallelic variants in ERLIN1: a series of 13 individuals with spastic paraparesis. Hum Genet 2024:10.1007/s00439-024-02702-0. [PMID: 39367212 DOI: 10.1007/s00439-024-02702-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2024] [Accepted: 09/09/2024] [Indexed: 10/06/2024]
Abstract
Biallelic variants in the ERLIN1 gene were recently reported as the cause of two motor neuron degeneration diseases, SPG62 and a recessive form of amyotrophic lateral sclerosis. However, only 12 individuals from five pedigrees have been identified so far. Thus, the description of the disease remains limited. Following the discovery of a homozygous pathogenic variant in a girl with SPG62, presenting with intellectual disability, and epilepsy, we gathered the largest series of SPG62 cases reported so far (13 individuals) to better understand the phenotype associated with ERLIN1. We collected molecular and clinical data for 13 individuals from six families with ERLIN1 biallelic variants. We performed RNA-seq analyses to characterize intronic variants and used Alphafold and a transcripts database to characterize the molecular consequences of the variants. We identified three new variants suspected to alter the bell-shaped ring formed by the ERLIN1/ERLIN2 complex. Affected individuals had childhood-onset paraparesis with slow progression. Six individuals presented with gait ataxia and three had superficial sensory loss. Aside from our proband, none had intellectual disability or epilepsy. Biallelic pathogenic ERLIN1 variants induce a rare, predominantly pure, spastic paraparesis, with possible cerebellar and peripheral nerve involvement.
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Affiliation(s)
- Guillaume Cogan
- APHP Sorbonne Université, Département de Génétique, Groupe Hospitalier Pitié-Salpêtrière-Hôpital Trousseau, Centre de Référence Déficiences Intellectuelles de Causes Rares, ERN-ITHACA, 47-83 Boulevard de l'hôpital, 75013, Paris, France
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | - Mahmoud Issa
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | - Boris Keren
- APHP Sorbonne Université, Département de Génétique, Groupe Hospitalier Pitié-Salpêtrière-Hôpital Trousseau, Centre de Référence Déficiences Intellectuelles de Causes Rares, ERN-ITHACA, 47-83 Boulevard de l'hôpital, 75013, Paris, France
| | - Marine Guillaud-Bataille
- APHP Sorbonne Université, Département de Génétique, Groupe Hospitalier Pitié-Salpêtrière-Hôpital Trousseau, Centre de Référence Déficiences Intellectuelles de Causes Rares, ERN-ITHACA, 47-83 Boulevard de l'hôpital, 75013, Paris, France
| | - Florence Renaldo
- APHP Sorbonne Université, Service de Neuropédiatrie, Centre de Référence Neurogénétique, Hôpital Armand Trousseau, Paris, France
| | - Arnaud Isapof
- APHP Sorbonne Université, Service de Neuropédiatrie, Centre de Référence Neurogénétique, Hôpital Armand Trousseau, Paris, France
| | - Pauline Lallemant
- APHP Sorbonne Université, Service de Médecine Physique et de Réadaptation Pédiatrique, Hôpital Armand Trousseau, Paris, France
- Sorbonne Université, Institut du Cerveau, Paris Brain Institute ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Giovanni Stevanin
- Sorbonne Université, Institut du Cerveau, Paris Brain Institute ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, Paris, France
- Bordeaux University, INCIA, UMR5287, CNRS, EPHE, 33000, Bordeaux, France
| | - Lena Guillot-Noel
- Sorbonne Université, Institut du Cerveau, Paris Brain Institute ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Thomas Courtin
- APHP Sorbonne Université, Département de Génétique, Groupe Hospitalier Pitié-Salpêtrière-Hôpital Trousseau, Centre de Référence Déficiences Intellectuelles de Causes Rares, ERN-ITHACA, 47-83 Boulevard de l'hôpital, 75013, Paris, France
| | - Julien Buratti
- APHP Sorbonne Université, Département de Génétique, Groupe Hospitalier Pitié-Salpêtrière-Hôpital Trousseau, Centre de Référence Déficiences Intellectuelles de Causes Rares, ERN-ITHACA, 47-83 Boulevard de l'hôpital, 75013, Paris, France
| | - Cécile Freihuber
- APHP Sorbonne Université, Service de Neuropédiatrie, Centre de Référence Neurogénétique, Hôpital Armand Trousseau, Paris, France
| | - Joseph G Gleeson
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, 92093, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, 92130, USA
| | - Robyn Howarth
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, 92093, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, 92130, USA
| | - Alexandra Durr
- Sorbonne Université, Institut du Cerveau, Paris Brain Institute ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Jean-Madeleine de Sainte Agathe
- APHP Sorbonne Université, Département de Génétique, Groupe Hospitalier Pitié-Salpêtrière-Hôpital Trousseau, Centre de Référence Déficiences Intellectuelles de Causes Rares, ERN-ITHACA, 47-83 Boulevard de l'hôpital, 75013, Paris, France
| | - Cyril Mignot
- APHP Sorbonne Université, Département de Génétique, Groupe Hospitalier Pitié-Salpêtrière-Hôpital Trousseau, Centre de Référence Déficiences Intellectuelles de Causes Rares, ERN-ITHACA, 47-83 Boulevard de l'hôpital, 75013, Paris, France.
- Sorbonne Université, Institut du Cerveau, Paris Brain Institute ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, Paris, France.
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3
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Rendel MD, Vitali C, Creasy KT, Zhang D, Scorletti E, Huang H, Seeling KS, Park J, Hehl L, Vell MS, Conlon D, Hayat S, Phillips MC, Schneider KM, Rader DJ, Schneider CV. The common p.Ile291Val variant of ERLIN1 enhances TM6SF2 function and is associated with protection against MASLD. MED 2024; 5:963-980.e5. [PMID: 38776916 DOI: 10.1016/j.medj.2024.04.010] [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: 11/04/2023] [Revised: 02/20/2024] [Accepted: 04/25/2024] [Indexed: 05/25/2024]
Abstract
BACKGROUND The ERLIN1 p.Ile291Val single-nucleotide polymorphism (rs2862954) is associated with protection from steatotic liver disease (SLD), but effects of this variant on metabolic phenotypes remain uncertain. METHODS Metabolic phenotypes and outcomes associated with ERLIN1 p.Ile291Val were analyzed by using a genome-first approach in the UK Biobank (UKB), Penn Medicine BioBank (PMBB), and All of Us cohort. FINDINGS ERLIN1 p.Ile291Val carriers exhibited significantly lower serum levels of alanine aminotransferase and aspartate aminotransferase as well as higher levels of triglycerides, low-density lipoprotein cholesterol, Apolipoprotein B, high-density lipoprotein cholesterol, and Apolipoprotein A1 in UKB, and these values were affected by ERLIN1 p.Ile291Val in an allele-dose-dependent manner. Homozygous ERLIN1 p.Ile291Val carriers had a significantly reduced risk of developing metabolic dysfunction-associated SLD (MASLD, adjusted odds ratio [aOR] = 0.92, 95% confidence interval [CI], 0.88-0.96). The protective effect of this variant was enhanced in patients with alcoholic liver disease. Our results were replicated in PMBB and the All of Us cohort. Strikingly, the protective effects of ERLIN1 p.Ile291Val were not apparent in individuals carrying the TM6SF2 p.Glu167Lys variant associated with increased risk of SLD. We analyzed the effects of predicted loss-of-function ERLIN1 variants and found that they had opposite effects, namely reduced plasma lipids, suggesting that ERLIN1 p.Ile291Val may be a gain-of-function variant. CONCLUSION Our study contributes to a better understanding of ERLIN1 by investigating a coding variant that has emerged as a potential gain-of-function mutation with protective effects against MASLD development.
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Affiliation(s)
- Miriam Daphne Rendel
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Cecilia Vitali
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kate Townsend Creasy
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David Zhang
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Eleonora Scorletti
- The Institute for Translational Medicine and Therapeutics, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Helen Huang
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Katharina Sophie Seeling
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Joseph Park
- The Institute for Translational Medicine and Therapeutics, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Leonida Hehl
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Mara Sophie Vell
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Donna Conlon
- The Institute for Translational Medicine and Therapeutics, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sikander Hayat
- Department of Medicine 2, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Michael C Phillips
- The Institute for Translational Medicine and Therapeutics, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kai Markus Schneider
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, 52074 Aachen, Germany; Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Daniel J Rader
- The Institute for Translational Medicine and Therapeutics, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Carolin Victoria Schneider
- Medical Clinic III, Gastroenterology, Metabolic Diseases and Intensive Care, University Hospital RWTH Aachen, 52074 Aachen, Germany; The Institute for Translational Medicine and Therapeutics, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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4
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Veronese M, Kallabis S, Kaczmarek AT, Das A, Robers L, Schumacher S, Lofrano A, Brodesser S, Müller S, Hofmann K, Krüger M, Rugarli EI. ERLIN1/2 scaffolds bridge TMUB1 and RNF170 and restrict cholesterol esterification to regulate the secretory pathway. Life Sci Alliance 2024; 7:e202402620. [PMID: 38782601 PMCID: PMC11116810 DOI: 10.26508/lsa.202402620] [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: 01/25/2024] [Revised: 05/06/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024] Open
Abstract
Complexes of ERLIN1 and ERLIN2 (ER lipid raft-associated 1 and 2) form large ring-like cup-shaped structures on the endoplasmic reticulum (ER) membrane and serve as platforms to bind cholesterol and E3 ubiquitin ligases, potentially defining functional nanodomains. Here, we show that ERLIN scaffolds mediate the interaction between the full-length isoform of TMUB1 (transmembrane and ubiquitin-like domain-containing 1) and RNF170 (RING finger protein 170). We identify a luminal N-terminal conserved region in TMUB1 and RNF170, which is required for this interaction. Three-dimensional modelling shows that this conserved motif binds the stomatin/prohibitin/flotillin/HflKC domain of two adjacent ERLIN subunits at different interfaces. Protein variants that preclude these interactions have been previously linked to hereditary spastic paraplegia. Using omics-based approaches in combination with phenotypic characterization of HeLa cells lacking both ERLINs, we demonstrate a role of ERLIN scaffolds in limiting cholesterol esterification, thereby favouring cholesterol transport from the ER to the Golgi apparatus and regulating Golgi morphology and the secretory pathway.
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Affiliation(s)
- Matteo Veronese
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Sebastian Kallabis
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Alexander Tobias Kaczmarek
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Anushka Das
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Lennart Robers
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Simon Schumacher
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Alessia Lofrano
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Susanne Brodesser
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Stefan Müller
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Kay Hofmann
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
| | - Marcus Krüger
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
- https://ror.org/00rcxh774 Center for Molecular Medicine (CMMC), University of Cologne, Cologne, Germany
| | - Elena I Rugarli
- https://ror.org/00rcxh774 Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
- https://ror.org/00rcxh774 Center for Molecular Medicine (CMMC), University of Cologne, Cologne, Germany
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5
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Elbatsh AMO, Amin-Mansour A, Haberkorn A, Textor C, Ebel N, Renard E, Koch LM, Groenveld FC, Piquet M, Naumann U, Ruddy DA, Romanet V, Martínez Gómez JM, Shirley MD, Wipfli P, Schnell C, Wartmann M, Rausch M, Jager MJ, Levesque MP, Maira SM, Manchado E. INPP5A phosphatase is a synthetic lethal target in GNAQ and GNA11-mutant melanomas. NATURE CANCER 2024; 5:481-499. [PMID: 38233483 DOI: 10.1038/s43018-023-00710-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 12/14/2023] [Indexed: 01/19/2024]
Abstract
Activating mutations in GNAQ/GNA11 occur in over 90% of uveal melanomas (UMs), the most lethal melanoma subtype; however, targeting these oncogenes has proven challenging and inhibiting their downstream effectors show limited clinical efficacy. Here, we performed genome-scale CRISPR screens along with computational analyses of cancer dependency and gene expression datasets to identify the inositol-metabolizing phosphatase INPP5A as a selective dependency in GNAQ/11-mutant UM cells in vitro and in vivo. Mutant cells intrinsically produce high levels of the second messenger inositol 1,4,5 trisphosphate (IP3) that accumulate upon suppression of INPP5A, resulting in hyperactivation of IP3-receptor signaling, increased cytosolic calcium and p53-dependent apoptosis. Finally, we show that GNAQ/11-mutant UM cells and patients' tumors exhibit elevated levels of IP4, a biomarker of enhanced IP3 production; these high levels are abolished by GNAQ/11 inhibition and correlate with sensitivity to INPP5A depletion. Our findings uncover INPP5A as a synthetic lethal vulnerability and a potential therapeutic target for GNAQ/11-mutant-driven cancers.
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Affiliation(s)
- Ahmed M O Elbatsh
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Ali Amin-Mansour
- Oncology, Novartis Institute for Biomedical Research, Cambridge, MA, USA
| | - Anne Haberkorn
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Claudia Textor
- PK Sciences, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Nicolas Ebel
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Emilie Renard
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Lisa M Koch
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Femke C Groenveld
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Michelle Piquet
- Oncology, Novartis Institute for Biomedical Research, Cambridge, MA, USA
| | - Ulrike Naumann
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - David A Ruddy
- Oncology, Novartis Institute for Biomedical Research, Cambridge, MA, USA
| | - Vincent Romanet
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Julia M Martínez Gómez
- Dermatology Department, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Matthew D Shirley
- Oncology, Novartis Institute for Biomedical Research, Cambridge, MA, USA
| | - Peter Wipfli
- PK Sciences, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Christian Schnell
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Markus Wartmann
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Martin Rausch
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, Basel, Switzerland
| | - Martine J Jager
- Department of Ophthalmology, Leiden University Medical Center, Leiden, The Netherlands
| | - Mitchell P Levesque
- Dermatology Department, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | | | - Eusebio Manchado
- Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland.
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6
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Gao X, Keller KR, Bonzerato CG, Li P, Laemmerhofer M, Wojcikiewicz RJH. The ubiquitin-proteasome pathway inhibitor TAK-243 has major effects on calcium handling in mammalian cells. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119618. [PMID: 37907195 DOI: 10.1016/j.bbamcr.2023.119618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/17/2023] [Accepted: 10/22/2023] [Indexed: 11/02/2023]
Abstract
The ubiquitin-proteasome pathway (UPP) is a major route for protein degradation and a key regulatory mechanism in mammalian cells. UPP inhibitors, including TAK-243, a first-in-class inhibitor of the E1 ubiquitin-activating enzyme, are currently being used and tested for treatment of a range of diseases, particularly cancer. Here, we reveal that TAK-243 has major effects on Ca2+ handling in a range of cultured mammalian cells (αT3, HeLa and SH-SY5Y). Effects were seen on agonist-induced Ca2+ mobilization, basal cytosolic Ca2+ levels, Ca2+ leak from the endoplasmic reticulum (ER), store-operated Ca2+ entry and mitochondrial Ca2+ uptake. These effects correlated with induction of ER stress, as measured by PERK activation / eIF2α phosphorylation, and most seemed to be underpinned by enhanced Ca2+ leak from the ER. Overall, these data indicate that TAK-243 reprograms the Ca2+-handling properties of mammalian cells and that these effects should be considered when UPP inhibitors are employed as therapeutic agents.
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Affiliation(s)
- Xiaokong Gao
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Katherine R Keller
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Caden G Bonzerato
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Peng Li
- Institute of Pharmaceutical Sciences, University of Tuebingen, Tuebingen 72076, Germany
| | - Michael Laemmerhofer
- Institute of Pharmaceutical Sciences, University of Tuebingen, Tuebingen 72076, Germany
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7
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Wang J, Zhao R, Cao H, Yin Z, Ma J, Xing Y, Zhang W, Chang X, Guo J. A novel autosomal dominant ERLIN2 variant activates endoplasmic reticulum stress in a Chinese HSP family. Ann Clin Transl Neurol 2023; 10:2139-2148. [PMID: 37752894 PMCID: PMC10646992 DOI: 10.1002/acn3.51902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 09/01/2023] [Accepted: 09/08/2023] [Indexed: 09/28/2023] Open
Abstract
OBJECTIVE Hereditary spastic paraplegia (HSP) has been reported rarely because of a monoallelic variant in ERLIN2. The present study aimed at describing a novel autosomal dominant ERLIN2 pedigree in a Chinese family and exploring the possible mechanism of HSP caused by ERLIN2 variants. METHODS The proband and his family underwent a comprehensive medical history inquiry and neurological examinations. Whole-exome sequencing was performed on the proband, and Sanger sequencing was performed on some family members. HeLa cell lines and mouse primary cortical neurons were used for immunofluorescence (IF) and reverse transcription-PCR (RT-PCR). RESULTS Seven patients were clinically diagnosed with pure spastic paraplegia in four consecutive generations with the autosomal dominant inheritance model. All patients presented juvenile-adolescent onset and gradually worsening pure HSP phenotype. Whole-exome sequencing of the proband and Sanger sequencing of all available family members identified a novel heterozygous c.212 T>C (p.V71A) variant in exon 8 of the ERLIN2 gene. The c.212 T>C demonstrated a high pathogenic effect score through functional prediction. RT-PCR and IF analysis of overexpressed V71A revealed an altered ER morphology and increased XBP-1S mRNA levels, suggesting the activation of ER stress. Overexpression of V71A in primary cultured cortical neurons promoted axon growth. INTERPRETATION The novel c.212 T>C heterozygous variant in human ERLIN2 caused pure HSP. Moreover, c.212 T>C heterozygous variant in ERLIN2 increased ER stress and affected axonal development.
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Affiliation(s)
- Juan Wang
- Department of NeurologyFirst Hospital of Shanxi Medical UniversityTaiyuanChina
- First Clinical Medical College, Shanxi Medical UniversityTaiyuanChina
| | - Rongjuan Zhao
- Department of NeurologyFirst Hospital of Shanxi Medical UniversityTaiyuanChina
| | - Hanshuai Cao
- First Clinical Medical College, Shanxi Medical UniversityTaiyuanChina
| | - Zhaoxu Yin
- First Clinical Medical College, Shanxi Medical UniversityTaiyuanChina
| | - Jing Ma
- First Clinical Medical College, Shanxi Medical UniversityTaiyuanChina
| | - Yingming Xing
- First Clinical Medical College, Shanxi Medical UniversityTaiyuanChina
| | - Wei Zhang
- Department of NeurologyFirst Hospital of Shanxi Medical UniversityTaiyuanChina
| | - Xueli Chang
- Department of NeurologyFirst Hospital of Shanxi Medical UniversityTaiyuanChina
| | - Junhong Guo
- Department of NeurologyFirst Hospital of Shanxi Medical UniversityTaiyuanChina
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8
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Christianson JC, Jarosch E, Sommer T. Mechanisms of substrate processing during ER-associated protein degradation. Nat Rev Mol Cell Biol 2023; 24:777-796. [PMID: 37528230 DOI: 10.1038/s41580-023-00633-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2023] [Indexed: 08/03/2023]
Abstract
Maintaining proteome integrity is essential for long-term viability of all organisms and is overseen by intrinsic quality control mechanisms. The secretory pathway of eukaryotes poses a challenge for such quality assurance as proteins destined for secretion enter the endoplasmic reticulum (ER) and become spatially segregated from the cytosolic machinery responsible for disposal of aberrant (misfolded or otherwise damaged) or superfluous polypeptides. The elegant solution provided by evolution is ER-membrane-bound ubiquitylation machinery that recognizes misfolded or surplus proteins or by-products of protein biosynthesis in the ER and delivers them to 26S proteasomes for degradation. ER-associated protein degradation (ERAD) collectively describes this specialized arm of protein quality control via the ubiquitin-proteasome system. But, instead of providing a single strategy to remove defective or unwanted proteins, ERAD represents a collection of independent processes that exhibit distinct yet overlapping selectivity for a wide range of substrates. Not surprisingly, ER-membrane-embedded ubiquitin ligases (ER-E3s) act as central hubs for each of these separate ERAD disposal routes. In these processes, ER-E3s cooperate with a plethora of specialized factors, coordinating recognition, transport and ubiquitylation of undesirable secretory, membrane and cytoplasmic proteins. In this Review, we focus on substrate processing during ERAD, highlighting common threads as well as differences between the many routes via ERAD.
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Affiliation(s)
- John C Christianson
- Botnar Research Centre, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK.
| | - Ernst Jarosch
- Max-Delbrück-Centrer for Molecular Medicine in Helmholtz Association, Berlin-Buch, Germany
| | - Thomas Sommer
- Max-Delbrück-Centrer for Molecular Medicine in Helmholtz Association, Berlin-Buch, Germany.
- Institute for Biology, Humboldt Universität zu Berlin, Berlin, Germany.
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9
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Yang Y, Shan S, Huang Z, Wang S, Liu Z, Yong H, Liu Z, Zhang C, Song F. Increased IP3R-3 degradation induced by acrylamide promoted Ca 2+-dependent calpain activation and axon damage in rats. Toxicol Lett 2023:S0378-4274(23)00203-5. [PMID: 37353096 DOI: 10.1016/j.toxlet.2023.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 04/23/2023] [Accepted: 06/10/2023] [Indexed: 06/25/2023]
Abstract
Occupational and environmental exposure to acrylamide (ACR) can cause selective peripheral and central nerve fiber degeneration. IP3R-3 is an important transmembrane Ca2+ channel on the endoplasmic reticulum (ER), previous studies have found that ACR could induce Ca2+-dependent calpain activation and axon injury, but the exact role of IP3R-3 in ACR neuropathy is still unclear. Here we show that ACR exposure (40mg/kg) markedly increased the ubiquitination of IP3R-3 in rat spinal cords, and promoted the degradation of IP3R-3 through the ubiquitin-proteasome pathway. Furthermore, the normal structure of ER, especially the mitochondrial associated membranes (MAMs) component, was significantly impaired in ACR neuropathy, and the ER stress pathway was activated, which indicated that the aberrant increase of cytoplasmic Ca2+ could be attributed the destruction of IP3R-3. Further investigation demonstrated that the proteasome inhibitor MG-132 effectively rescued the IP3R-3 loss, attenuated the intracellular Ca2+ increase, and reduced the axon loss of Neuron 2a (N2a) cells following ACR exposure. Moreover, the calpain inhibitor ALLN also reduced the loss of IP3R-3 and axon injury in N2a cells, but did not alleviate the Ca2+ increase in cytosol, supporting that the abnormal ubiquitination of IP3R-3 was the upstream of the cellular Ca2+ rise and axon damage in ACR neuropathy. Taken together, our results suggested that the aberrant IP3R-3 degradation played an important role in the disturbance of Ca2+ homeostasis and the downstream axon loss in ACR neuropathy, thus providing a potential therapeutic target for ACR neurotoxicity.
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Affiliation(s)
- Yiyu Yang
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Shulin Shan
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Zhengcheng Huang
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Shuai Wang
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Zhaoxiong Liu
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Hui Yong
- Qingdao Municipal Center for Disease Control and Prevention, Qingdao, Shandong, 266000, China
| | - Zhidan Liu
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Cuiqin Zhang
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China; School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Fuyong Song
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China.
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10
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Bonzerato CG, Keller KR, Schulman JJ, Gao X, Szczesniak LM, Wojcikiewicz RJH. Endogenous Bok is stable at the endoplasmic reticulum membrane and does not mediate proteasome inhibitor-induced apoptosis. Front Cell Dev Biol 2022; 10:1094302. [PMID: 36601536 PMCID: PMC9806350 DOI: 10.3389/fcell.2022.1094302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022] Open
Abstract
Controversy surrounds the cellular role of the Bcl-2 family protein Bok. On one hand, it has been shown that all endogenous Bok is bound to inositol 1,4,5-trisphosphate receptors (IP3Rs), while other data suggest that Bok can act as a pro-apoptotic mitochondrial outer membrane permeabilization mediator, apparently kept at very low and non-apoptotic levels by efficient proteasome-mediated degradation. Here we show that 1) endogenous Bok is expressed at readily-detectable levels in key cultured cells (e.g., mouse embryonic fibroblasts and HCT116 cells) and is not constitutively degraded by the proteasome, 2) proteasome inhibitor-induced apoptosis is not mediated by Bok, 3) endogenous Bok expression level is critically dependent on the presence of IP3Rs, 4) endogenous Bok is rapidly degraded by the ubiquitin-proteasome pathway in the absence of IP3Rs at the endoplasmic reticulum membrane, and 5) charged residues in the transmembrane region of Bok affect its stability, ability to interact with Mcl-1, and pro-apoptotic activity when over-expressed. Overall, these data indicate that endogenous Bok levels are not governed by proteasomal activity (except when IP3Rs are deleted) and that while endogenous Bok plays little or no role in apoptotic signaling, exogenous Bok can mediate apoptosis in a manner dependent on its transmembrane domain.
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11
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Bhattacharya A, Wei J, Song W, Gao B, Tian C, Wu SA, Wang J, Chen L, Fang D, Qi L. SEL1L-HRD1 ER-associated degradation suppresses hepatocyte hyperproliferation and liver cancer. iScience 2022; 25:105183. [PMID: 36238898 PMCID: PMC9550610 DOI: 10.1016/j.isci.2022.105183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/15/2022] [Accepted: 09/20/2022] [Indexed: 11/02/2022] Open
Abstract
Endoplasmic reticulum (ER) homeostasis has been implicated in the pathogenesis of various forms of cancer; however, our understanding of the role of ER quality control mechanisms in tumorigenesis remains incomplete. Here, we show that the SEL1L-HRD1 complex of ER-associated degradation (ERAD) suppresses hepatocyte proliferation and tumorigenesis in mice. Hepatocyte-specific deletion of Sel1L or Hrd1 predisposed mice to diet/chemical-induced tumors. Proteomics screen from SEL1L-deficient livers revealed WNT5A, a tumor suppressor, as an ERAD substrate. Indeed, nascent WNT5A was misfolding prone and degraded by SEL1L-HRD1 ERAD in a quality control capacity. In the absence of ERAD, WNT5A misfolds is largely retained in the ER and forms high-molecular weight aggregates, thereby depicting a loss-of-function effect and attenuating WNT5A-mediated suppression of hepatocyte proliferation. In humans, SEL1L-HRD1 ERAD expression correlated positively with survival time for patients with liver cancer. Overall, our data reveal a key role of SEL1L-HRD1 ERAD in suppressing hepatocyte proliferation and liver cancer.
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Affiliation(s)
- Asmita Bhattacharya
- Department of Molecular and 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
| | - Juncheng Wei
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Wenxin Song
- School of Pharmaceutical Sciences, Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China
| | - Beixue Gao
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Chunyan Tian
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Shuangcheng Alivia Wu
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Jian Wang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Ligong Chen
- School of Pharmaceutical Sciences, Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China
| | - Deyu Fang
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Ling Qi
- Department of Molecular and 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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12
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Wang YJ, Di XJ, Mu TW. Quantitative interactome proteomics identifies a proteostasis network for GABA A receptors. J Biol Chem 2022; 298:102423. [PMID: 36030824 PMCID: PMC9493394 DOI: 10.1016/j.jbc.2022.102423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 08/17/2022] [Accepted: 08/19/2022] [Indexed: 11/29/2022] Open
Abstract
Gamma-aminobutyric acid type A (GABAA) receptors are the primary inhibitory neurotransmitter-gated ion channels in the mammalian central nervous system. Maintenance of GABAA receptor protein homeostasis (proteostasis) in cells utilizing its interacting proteins is essential for the function of GABAA receptors. However, how the proteostasis network orchestrates GABAA receptor biogenesis in the endoplasmic reticulum is not well understood. Here, we employed a proteomics-based approach to systematically identify the interactomes of GABAA receptors. We carried out a quantitative immunoprecipitation-tandem mass spectrometry analysis utilizing stable isotope labeling by amino acids in cell culture. Furthermore, we performed comparative proteomics by using both WT α1 subunit and a misfolding-prone α1 subunit carrying the A322D variant as the bait proteins. We identified 125 interactors for WT α1-containing receptors, 105 proteins for α1(A322D)-containing receptors, and 54 overlapping proteins within these two interactomes. Our bioinformatics analysis identified potential GABAA receptor proteostasis network components, including chaperones, folding enzymes, trafficking factors, and degradation factors, and we assembled a model of their potential involvement in the cellular folding, degradation, and trafficking pathways for GABAA receptors. In addition, we verified endogenous interactions between α1 subunits and selected interactors by using coimmunoprecipitation in mouse brain homogenates. Moreover, we showed that TRIM21 (tripartite motif containing-21), an E3 ubiquitin ligase, positively regulated the degradation of misfolding-prone α1(A322D) subunits selectively. This study paves the way for understanding the molecular mechanisms as well as fine-tuning of GABAA receptor proteostasis to ameliorate related neurological diseases such as epilepsy.
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Affiliation(s)
- Ya-Juan Wang
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA; Center for Proteomics and Bioinformatics, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
| | - Xiao-Jing Di
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
| | - Ting-Wei Mu
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
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13
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Zhao J, Zhang H, Fan X, Yu X, Huai J. Lipid Dyshomeostasis and Inherited Cerebellar Ataxia. Mol Neurobiol 2022; 59:3800-3828. [PMID: 35420383 PMCID: PMC9148275 DOI: 10.1007/s12035-022-02826-2] [Citation(s) in RCA: 2] [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: 03/29/2021] [Accepted: 04/01/2022] [Indexed: 12/04/2022]
Abstract
Cerebellar ataxia is a form of ataxia that originates from dysfunction of the cerebellum, but may involve additional neurological tissues. Its clinical symptoms are mainly characterized by the absence of voluntary muscle coordination and loss of control of movement with varying manifestations due to differences in severity, in the site of cerebellar damage and in the involvement of extracerebellar tissues. Cerebellar ataxia may be sporadic, acquired, and hereditary. Hereditary ataxia accounts for the majority of cases. Hereditary ataxia has been tentatively divided into several subtypes by scientists in the field, and nearly all of them remain incurable. This is mainly because the detailed mechanisms of these cerebellar disorders are incompletely understood. To precisely diagnose and treat these diseases, studies on their molecular mechanisms have been conducted extensively in the past. Accumulating evidence has demonstrated that some common pathogenic mechanisms exist within each subtype of inherited ataxia. However, no reports have indicated whether there is a common mechanism among the different subtypes of inherited cerebellar ataxia. In this review, we summarize the available references and databases on neurological disorders characterized by cerebellar ataxia and show that a subset of genes involved in lipid homeostasis form a new group that may cause ataxic disorders through a common mechanism. This common signaling pathway can provide a valuable reference for future diagnosis and treatment of ataxic disorders.
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Affiliation(s)
- Jin Zhao
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Huan Zhang
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Xueyu Fan
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Xue Yu
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Jisen Huai
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China.
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China.
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14
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Binding of the erlin1/2 complex to the third intralumenal loop of IP 3R1 triggers its ubiquitin-proteasomal degradation. J Biol Chem 2022; 298:102026. [PMID: 35568199 PMCID: PMC9168715 DOI: 10.1016/j.jbc.2022.102026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 05/04/2022] [Accepted: 05/05/2022] [Indexed: 11/21/2022] Open
Abstract
Long-term activation of inositol 1,4,5-trisphosphate receptors (IP3Rs) leads to their degradation by the ubiquitin–proteasome pathway. The first and rate-limiting step in this process is thought to be the association of conformationally active IP3Rs with the erlin1/2 complex, an endoplasmic reticulum–located oligomer of erlin1 and erlin2 that recruits the E3 ubiquitin ligase RNF170, but the molecular determinants of this interaction remain unknown. Here, through mutation of IP3R1, we show that the erlin1/2 complex interacts with the IP3R1 intralumenal loop 3 (IL3), the loop between transmembrane (TM) helices 5 and 6, and in particular, with a region close to TM5, since mutation of amino acids D-2471 and R-2472 can specifically block erlin1/2 complex association. Surprisingly, we found that additional mutations in IL3 immediately adjacent to TM5 (e.g., D2465N) almost completely abolish IP3R1 Ca2+ channel activity, indicating that the integrity of this region is critical to IP3R1 function. Finally, we demonstrate that inhibition of the ubiquitin-activating enzyme UBE1 by the small-molecule inhibitor TAK-243 completely blocked IP3R1 ubiquitination and degradation without altering erlin1/2 complex association, confirming that association of the erlin1/2 complex is the primary event that initiates IP3R1 processing and that IP3R1 ubiquitination mediates IP3R1 degradation. Overall, these data localize the erlin1/2 complex–binding site on IP3R1 to IL3 and show that the region immediately adjacent to TM5 is key to the events that facilitate channel opening.
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15
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Role of ERLINs in the Control of Cell Fate through Lipid Rafts. Cells 2021; 10:cells10092408. [PMID: 34572057 PMCID: PMC8470593 DOI: 10.3390/cells10092408] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/27/2021] [Accepted: 09/09/2021] [Indexed: 12/14/2022] Open
Abstract
ER lipid raft-associated protein 1 (ERLIN1) and 2 (ERLIN2) are 40 kDa transmembrane glycoproteins belonging to the family of prohibitins, containing a PHB domain. They are generally localized in the endoplasmic reticulum (ER), where ERLIN1 forms a heteroligomeric complex with its closely related ERLIN2. Well-defined functions of ERLINS are promotion of ER-associated protein degradation, mediation of inositol 1,4,5-trisphosphate (IP3) receptors, processing and regulation of lipid metabolism. Until now, ERLINs have been exclusively considered protein markers of ER lipid raft-like microdomains. However, under pathophysiological conditions, they have been described within mitochondria-associated endoplasmic reticulum membranes (MAMs), tethering sites between ER and mitochondria, characterized by the presence of specialized raft-like subdomains enriched in cholesterol and gangliosides, which play a key role in the membrane scrambling and function. In this context, it is emerging that ER lipid raft-like microdomains proteins, i.e., ERLINs, may drive mitochondria-ER crosstalk under both physiological and pathological conditions by association with MAMs, regulating the two main processes underlined, survival and death. In this review, we describe the role of ERLINs in determining cell fate by controlling the “interchange” between apoptosis and autophagy pathways, considering that their alteration has a significant impact on the pathogenesis of several human diseases.
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16
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The Targeting of Native Proteins to the Endoplasmic Reticulum-Associated Degradation (ERAD) Pathway: An Expanding Repertoire of Regulated Substrates. Biomolecules 2021; 11:biom11081185. [PMID: 34439852 PMCID: PMC8393694 DOI: 10.3390/biom11081185] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/05/2021] [Accepted: 08/08/2021] [Indexed: 12/22/2022] Open
Abstract
All proteins are subject to quality control processes during or soon after their synthesis, and these cellular quality control pathways play critical roles in maintaining homeostasis in the cell and in organism health. Protein quality control is particularly vital for those polypeptides that enter the endoplasmic reticulum (ER). Approximately one-quarter to one-third of all proteins synthesized in eukaryotic cells access the ER because they are destined for transport to the extracellular space, because they represent integral membrane proteins, or because they reside within one of the many compartments of the secretory pathway. However, proteins that mature inefficiently are subject to ER-associated degradation (ERAD), a multi-step pathway involving the chaperone-mediated selection, ubiquitination, and extraction (or “retrotranslocation”) of protein substrates from the ER. Ultimately, these substrates are degraded by the cytosolic proteasome. Interestingly, there is an increasing number of native enzymes and metabolite and solute transporters that are also targeted for ERAD. While some of these proteins may transiently misfold, the ERAD pathway also provides a route to rapidly and quantitatively downregulate the levels and thus the activities of a variety of proteins that mature or reside in the ER.
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17
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Huang SSY, Toufiq M, Saraiva LR, Van Panhuys N, Chaussabel D, Garand M. Transcriptome and Literature Mining Highlight the Differential Expression of ERLIN1 in Immune Cells during Sepsis. BIOLOGY 2021; 10:755. [PMID: 34439987 PMCID: PMC8389572 DOI: 10.3390/biology10080755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 07/24/2021] [Accepted: 07/27/2021] [Indexed: 12/20/2022]
Abstract
Sepsis results from the dysregulation of the host immune system. This highly variable disease affects 19 million people globally, and accounts for 5 million deaths annually. In transcriptomic datasets curated from public repositories, we observed a consistent upregulation (3.26-5.29 fold) of ERLIN1-a gene coding for an ER membrane prohibitin and a regulator of inositol 1, 4, 5-trisphosphate receptors and sterol regulatory element-binding proteins-under septic conditions in healthy neutrophils, monocytes, and whole blood. In vitro expression of the ERLIN1 gene and proteins was measured by stimulating the whole blood of healthy volunteers to a combination of lipopolysaccharide and peptidoglycan. Septic stimulation induced a significant increase in ERLIN1 expression; however, ERLIN1 was differentially expressed among the immune blood cell subsets. ERLIN1 was uniquely increased in whole blood neutrophils, and confirmed in the differentiated HL60 cell line. The scarcity of ERLIN1 in sepsis literature indicates a knowledge gap between the functions of ERLIN1, calcium homeostasis, and cholesterol and fatty acid biosynthesis, and sepsis. In combination with experimental data, we bring forth the hypothesis that ERLIN1 is variably modulated among immune cells in response to cellular perturbations, and has implications for ER functions and/or ER membrane protein components during sepsis.
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Affiliation(s)
- Susie S. Y. Huang
- Research Department, Sidra Medicine, Doha 26999, Qatar; (M.T.); (L.R.S.); (N.V.P.); (D.C.)
| | - Mohammed Toufiq
- Research Department, Sidra Medicine, Doha 26999, Qatar; (M.T.); (L.R.S.); (N.V.P.); (D.C.)
| | - Luis R. Saraiva
- Research Department, Sidra Medicine, Doha 26999, Qatar; (M.T.); (L.R.S.); (N.V.P.); (D.C.)
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha 34110, Qatar
| | - Nicholas Van Panhuys
- Research Department, Sidra Medicine, Doha 26999, Qatar; (M.T.); (L.R.S.); (N.V.P.); (D.C.)
| | - Damien Chaussabel
- Research Department, Sidra Medicine, Doha 26999, Qatar; (M.T.); (L.R.S.); (N.V.P.); (D.C.)
| | - Mathieu Garand
- Research Department, Sidra Medicine, Doha 26999, Qatar; (M.T.); (L.R.S.); (N.V.P.); (D.C.)
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18
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Wolf LM, Lambert AM, Haenlin J, Boutros M. EVI/WLS function is regulated by ubiquitination and linked to ER-associated degradation by ERLIN2. J Cell Sci 2021; 134:271857. [PMID: 34406391 PMCID: PMC8435288 DOI: 10.1242/jcs.257790] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 07/12/2021] [Indexed: 12/16/2022] Open
Abstract
WNT signalling is important for development in all metazoans and is associated with various human diseases. The ubiquitin–proteasome system (UPS) and regulatory endoplasmic reticulum-associated degradation (ERAD) have been implicated in the production of WNT proteins. Here, we investigated how the WNT secretory factor EVI (also known as WLS) is ubiquitylated, recognised by ERAD components and subsequently removed from the secretory pathway. We performed a focused immunoblot-based RNAi screen for factors that influence EVI/WLS protein stability. We identified the VCP-binding proteins FAF2 and UBXN4 as novel interaction partners of EVI/WLS and showed that ERLIN2 links EVI/WLS to the ubiquitylation machinery. Interestingly, we also found that EVI/WLS is ubiquitylated and degraded in cells irrespective of their level of WNT production. This K11, K48 and K63-linked ubiquitylation is mediated by the E2 ubiquitin-conjugating enzymes UBE2J2, UBE2K and UBE2N, but is independent of the E3 ubiquitin ligases HRD1 (also known as SYVN1) and GP78 (also known as AMFR). Taken together, our study identifies factors that link the UPS to the WNT secretory pathway and provides mechanistic details of the fate of an endogenous substrate of regulatory ERAD in mammalian cells. This article has an associated First Person interview with the first author of the paper. Summary: The WNT secretory factor EVI/WLS is ubiquitylated and linked to ER-associated degradation by multiple proteins, providing insight into the link between WNT signalling and the ubiquitin–proteasome system.
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Affiliation(s)
- Lucie M Wolf
- German Cancer Research Center (DKFZ), Division of Signalling and Functional Genomics and Heidelberg University, BioQuant & Department for Cell and Molecular Biology, Medical Faculty Mannheim, D-69120 Heidelberg, Germany
| | - Annika M Lambert
- German Cancer Research Center (DKFZ), Division of Signalling and Functional Genomics and Heidelberg University, BioQuant & Department for Cell and Molecular Biology, Medical Faculty Mannheim, D-69120 Heidelberg, Germany
| | - Julie Haenlin
- German Cancer Research Center (DKFZ), Division of Signalling and Functional Genomics and Heidelberg University, BioQuant & Department for Cell and Molecular Biology, Medical Faculty Mannheim, D-69120 Heidelberg, Germany
| | - Michael Boutros
- German Cancer Research Center (DKFZ), Division of Signalling and Functional Genomics and Heidelberg University, BioQuant & Department for Cell and Molecular Biology, Medical Faculty Mannheim, D-69120 Heidelberg, Germany
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19
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Steinle H, Ellwanger K, Mirza N, Briese S, Kienes I, Pfannstiel J, Kufer TA. 14-3-3 and erlin proteins differentially interact with RIPK2 complexes. J Cell Sci 2021; 134:jcs258137. [PMID: 34152391 DOI: 10.1242/jcs.258137] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 05/19/2021] [Indexed: 01/11/2023] Open
Abstract
The receptor interacting serine/threonine kinase 2 (RIPK2) is essential for signal transduction induced by the pattern recognition receptors NOD1 and NOD2 (referred to collectively as NOD1/2). Upon NOD1/2 activation, RIPK2 forms complexes in the cytoplasm of human cells. Here, we identified the molecular composition of these complexes. Infection with Shigella flexneri to activate NOD1-RIPK2 revealed that RIPK2 formed dynamic interactions with several cellular proteins, including A20 (also known as TNFAIP3), erlin-1, erlin-2 and 14-3-3. Whereas interaction of RIPK2 with 14-3-3 proteins was strongly reduced upon infection with Shigella, erlin-1 and erlin-2 (erlin-1/2) specifically bound to RIPK2 complexes. The interaction of these proteins with RIPK2 was validated using protein binding assays and immunofluorescence staining. Beside bacterial activation of NOD1/2, depletion of the E3 ubiquitin ligase XIAP and treatment with RIPK2 inhibitors also led to the formation of RIPK2 cytosolic complexes. Although erlin-1/2 were recruited to RIPK2 complexes following XIAP inhibition, these proteins did not associate with RIPK2 structures induced by RIPK2 inhibitors. While the specific recruitment of erlin-1/2 to RIPK2 suggests a role in innate immune signaling, the biological response regulated by the erlin-1/2-RIPK2 association remains to be determined.
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Affiliation(s)
- Heidrun Steinle
- Department of Immunology, Institute of Nutritional Medicine, University of Hohenheim, 70619 Stuttgart, Germany
| | - Kornelia Ellwanger
- Department of Immunology, Institute of Nutritional Medicine, University of Hohenheim, 70619 Stuttgart, Germany
| | - Nora Mirza
- Department of Immunology, Institute of Nutritional Medicine, University of Hohenheim, 70619 Stuttgart, Germany
| | - Selina Briese
- Department of Immunology, Institute of Nutritional Medicine, University of Hohenheim, 70619 Stuttgart, Germany
| | - Ioannis Kienes
- Department of Immunology, Institute of Nutritional Medicine, University of Hohenheim, 70619 Stuttgart, Germany
| | - Jens Pfannstiel
- Core Facility Hohenheim Mass Spectrometry Module, Institute of Nutritional Medicine, University of Hohenheim, 70619 Stuttgart, Germany
| | - Thomas A Kufer
- Department of Immunology, Institute of Nutritional Medicine, University of Hohenheim, 70619 Stuttgart, Germany
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20
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Lemberg MK, Strisovsky K. Maintenance of organellar protein homeostasis by ER-associated degradation and related mechanisms. Mol Cell 2021; 81:2507-2519. [PMID: 34107306 DOI: 10.1016/j.molcel.2021.05.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/14/2021] [Accepted: 05/05/2021] [Indexed: 12/19/2022]
Abstract
Protein homeostasis mechanisms are fundamentally important to match cellular needs and to counteract stress conditions. A fundamental challenge is to understand how defective proteins are recognized and extracted from cellular organelles to be degraded in the cytoplasm. The endoplasmic reticulum (ER)-associated degradation (ERAD) pathway is the best-understood organellar protein quality control system. Here, we review new insights into the mechanism of recognition and retrotranslocation of client proteins in ERAD. In addition to the membrane-integral ERAD E3 ubiquitin ligases, we highlight one protein family that is remarkably often involved in various aspects of membrane protein quality control and protein dislocation: the rhomboid superfamily, which includes derlins and intramembrane serine proteases. Rhomboid-like proteins have been found to control protein homeostasis in the ER, but also in other eukaryotic organelles and in bacteria, pointing toward conserved principles of membrane protein quality control across organelles and evolution.
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Affiliation(s)
- Marius K Lemberg
- Center for Molecular Biology of Heidelberg University (ZMBH), Im Neuenheimer Feld 282, 69120 Heidelberg, Germany; Center for Biochemistry, Medical Faculty, University of Cologne, Joseph-Stelzmann-Strasse 52, 50931 Cologne, Germany.
| | - Kvido Strisovsky
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czechia.
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21
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Szczesniak LM, Bonzerato CG, Wojcikiewicz RJH. Identification of the Bok Interactome Using Proximity Labeling. Front Cell Dev Biol 2021; 9:689951. [PMID: 34136494 PMCID: PMC8201613 DOI: 10.3389/fcell.2021.689951] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 05/06/2021] [Indexed: 12/28/2022] Open
Abstract
The function of the Bcl-2 family member Bok is currently enigmatic, with various disparate roles reported, including mediation of apoptosis, regulation of mitochondrial morphology, binding to inositol 1,4,5-trisphosphate receptors, and regulation of uridine metabolism. To better define the roles of Bok, we examined its interactome using TurboID-mediated proximity labeling in HeLa cells, in which Bok knock-out leads to mitochondrial fragmentation and Bok overexpression leads to apoptosis. Labeling with TurboID-Bok revealed that Bok was proximal to a wide array of proteins, particularly those involved in mitochondrial fission (e.g., Drp1), endoplasmic reticulum-plasma membrane junctions (e.g., Stim1), and surprisingly among the Bcl-2 family members, just Mcl-1. Comparison with TurboID-Mcl-1 and TurboID-Bak revealed that the three Bcl-2 family member interactomes were largely independent, but with some overlap that likely identifies key interactors. Interestingly, when overexpressed, Mcl-1 and Bok interact physically and functionally, in a manner that depends upon the transmembrane domain of Bok. Overall, this work shows that the Bok interactome is different from those of Mcl-1 and Bak, identifies novel proximities and potential interaction points for Bcl-2 family members, and suggests that Bok may regulate mitochondrial fission via Mcl-1 and Drp1.
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22
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Tadepalle N, Rugarli EI. Lipid Droplets in the Pathogenesis of Hereditary Spastic Paraplegia. Front Mol Biosci 2021; 8:673977. [PMID: 34041268 PMCID: PMC8141572 DOI: 10.3389/fmolb.2021.673977] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/26/2021] [Indexed: 12/21/2022] Open
Abstract
Hereditary spastic paraplegias (HSPs) are genetically heterogeneous conditions caused by the progressive dying back of the longest axons in the central nervous system, the corticospinal axons. A wealth of data in the last decade has unraveled disturbances of lipid droplet (LD) biogenesis, maturation, turnover and contact sites in cellular and animal models with perturbed expression and function of HSP proteins. As ubiquitous organelles that segregate neutral lipid into a phospholipid monolayer, LDs are at the cross-road of several processes including lipid metabolism and trafficking, energy homeostasis, and stress signaling cascades. However, their role in brain cells, especially in neurons remains enigmatic. Here, we review experimental findings linking LD abnormalities to defective function of proteins encoded by HSP genes, and discuss arising questions in the context of the pathogenesis of HSP.
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Affiliation(s)
- Nimesha Tadepalle
- Molecular and Cell Biology Laboratory, Salk Institute of Biological Sciences, La Jolla, CA, United States
| | - Elena I Rugarli
- Institute for Genetics, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany.,Center for Molecular Medicine (CMMC),Cologne, Germany
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23
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Szczesniak LM, Bonzerato CG, Schulman JJ, Bah A, Wojcikiewicz RJH. Bok binds to a largely disordered loop in the coupling domain of type 1 inositol 1,4,5-trisphosphate receptor. Biochem Biophys Res Commun 2021; 553:180-186. [PMID: 33773141 DOI: 10.1016/j.bbrc.2021.03.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 03/09/2021] [Indexed: 12/28/2022]
Abstract
Bcl-2-related ovarian killer (Bok) binds tightly to inositol 1,4,5-trisphosphate receptors (IP3Rs). To better understand this interaction, we sought to elucidate the Bok binding determinants in IP3R1, focusing on the ∼75 amino acid loop (residues 1882-1957) between α helices 72 and 73. Bioinformatic analysis revealed that the majority of this loop is intrinsically disordered, with two flanking regions of high disorder next to a low disorder central region (∼residues 1914-1926) that is predicted to contain two fused, disjointed transient helical elements. Experiments with IP3R1 mutants, combined with computational analysis, indicated that small deletions in this central region block Bok binding due to perturbation of the helical elements. Studies in vitro with purified Bok and IP3R1-derived peptides revealed high affinity binding to amino acids 1898-1940 of IP3R1 (Kd ∼65 nM) and that binding affinity is also dependent upon both of the high disorder flanking regions. The strength of the Bok-IP3R1 interaction was demonstrated by the ability of IP3R1 or Bok to recruit transmembrane domain-free Bok or IP3R1 mutants, respectively, to membranes in intact cells, and that these two mutants can bind in the cytosol independently of membrane association. Overall, we show that Bok binding to IP3R1 occurs within a largely disordered loop between α helices 72 and 73 and that high affinity binding is mediated by multivalent interactions.
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Affiliation(s)
- Laura M Szczesniak
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, USA
| | - Caden G Bonzerato
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, USA
| | | | - Alaji Bah
- Department of Biochemistry, Department of Molecular Biology, SUNY Upstate Medical University, Syracuse, NY, USA
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24
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Fenech EJ, Lari F, Charles PD, Fischer R, Laétitia-Thézénas M, Bagola K, Paton AW, Paton JC, Gyrd-Hansen M, Kessler BM, Christianson JC. Interaction mapping of endoplasmic reticulum ubiquitin ligases identifies modulators of innate immune signalling. eLife 2020; 9:e57306. [PMID: 32614325 PMCID: PMC7332293 DOI: 10.7554/elife.57306] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 06/11/2020] [Indexed: 12/25/2022] Open
Abstract
Ubiquitin ligases (E3s) embedded in the endoplasmic reticulum (ER) membrane regulate essential cellular activities including protein quality control, calcium flux, and sterol homeostasis. At least 25 different, transmembrane domain (TMD)-containing E3s are predicted to be ER-localised, but for most their organisation and cellular roles remain poorly defined. Using a comparative proteomic workflow, we mapped over 450 protein-protein interactions for 21 stably expressed, full-length E3s. Bioinformatic analysis linked ER-E3s and their interactors to multiple homeostatic, regulatory, and metabolic pathways. Among these were four membrane-embedded interactors of RNF26, a polytopic E3 whose abundance is auto-regulated by ubiquitin-proteasome dependent degradation. RNF26 co-assembles with TMEM43, ENDOD1, TMEM33 and TMED1 to form a complex capable of modulating innate immune signalling through the cGAS-STING pathway. This RNF26 complex represents a new modulatory axis of STING and innate immune signalling at the ER membrane. Collectively, these data reveal the broad scope of regulation and differential functionalities mediated by ER-E3s for both membrane-tethered and cytoplasmic processes.
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Affiliation(s)
- Emma J Fenech
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
| | - Federica Lari
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
| | - Philip D Charles
- TDI Mass Spectrometry Laboratory, Target Discovery Institute, University of OxfordOxfordUnited Kingdom
| | - Roman Fischer
- TDI Mass Spectrometry Laboratory, Target Discovery Institute, University of OxfordOxfordUnited Kingdom
| | - Marie Laétitia-Thézénas
- TDI Mass Spectrometry Laboratory, Target Discovery Institute, University of OxfordOxfordUnited Kingdom
| | - Katrin Bagola
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
| | - Adrienne W Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of AdelaideAdelaideAustralia
| | - James C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of AdelaideAdelaideAustralia
| | - Mads Gyrd-Hansen
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
| | - Benedikt M Kessler
- TDI Mass Spectrometry Laboratory, Target Discovery Institute, University of OxfordOxfordUnited Kingdom
- Chinese Academy of Medical Sciences Oxford Institute, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
| | - John C Christianson
- Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
- Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, University of Oxford, Botnar Research CentreOxfordUnited Kingdom
- Oxford Centre for Translational Myeloma Research, University of Oxford, Botnar Research CentreOxfordUnited Kingdom
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25
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Knopf JD, Landscheidt N, Pegg CL, Schulz BL, Kühnle N, Chao CW, Huck S, Lemberg MK. Intramembrane protease RHBDL4 cleaves oligosaccharyltransferase subunits to target them for ER-associated degradation. J Cell Sci 2020; 133:jcs243790. [PMID: 32005703 DOI: 10.1242/jcs.243790] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 01/21/2020] [Indexed: 08/31/2023] Open
Abstract
The endoplasmic reticulum (ER)-resident intramembrane rhomboid protease RHBDL4 generates metastable protein fragments and together with the ER-associated degradation (ERAD) machinery provides a clearance mechanism for aberrant and surplus proteins. However, the endogenous substrate spectrum and with that the role of RHBDL4 in physiological ERAD is mainly unknown. Here, we use a substrate trapping approach in combination with quantitative proteomics to identify physiological RHBDL4 substrates. This revealed oligosaccharyltransferase (OST) complex subunits such as the catalytic active subunit STT3A as substrates for the RHBDL4-dependent ERAD pathway. RHBDL4-catalysed cleavage inactivates OST subunits by triggering dislocation into the cytoplasm and subsequent proteasomal degradation. RHBDL4 thereby controls the abundance and activity of OST, suggesting a novel link between the ERAD machinery and glycosylation tuning.
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Affiliation(s)
- Julia D Knopf
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Nina Landscheidt
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Cassandra L Pegg
- School of Chemistry and Molecular Biosciences, ARC Training Centre for Biopharmaceutical Innovation, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Benjamin L Schulz
- School of Chemistry and Molecular Biosciences, ARC Training Centre for Biopharmaceutical Innovation, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Nathalie Kühnle
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Chao-Wei Chao
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Simon Huck
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Marius K Lemberg
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
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26
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Rosa N, Sneyers F, Parys JB, Bultynck G. Type 3 IP 3 receptors: The chameleon in cancer. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 351:101-148. [PMID: 32247578 DOI: 10.1016/bs.ircmb.2020.02.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Inositol 1,4,5-trisphosphate (IP3) receptors (IP3Rs), intracellular calcium (Ca2+) release channels, fulfill key functions in cell death and survival processes, whose dysregulation contributes to oncogenesis. This is essentially due to the presence of IP3Rs in microdomains of the endoplasmic reticulum (ER) in close proximity to the mitochondria. As such, IP3Rs enable efficient Ca2+ transfers from the ER to the mitochondria, thus regulating metabolism and cell fate. This review focuses on one of the three IP3R isoforms, the type 3 IP3R (IP3R3), which is linked to proapoptotic ER-mitochondrial Ca2+ transfers. Alterations in IP3R3 expression have been highlighted in numerous cancer types, leading to dysregulations of Ca2+ signaling and cellular functions. However, the outcome of IP3R3-mediated Ca2+ transfers for mitochondrial function is complex with opposing effects on oncogenesis. IP3R3 can either suppress cancer by promoting cell death and cellular senescence or support cancer by driving metabolism, anabolic processes, cell cycle progression, proliferation and invasion. The aim of this review is to provide an overview of IP3R3 dysregulations in cancer and describe how such dysregulations alter critical cellular processes such as proliferation or cell death and survival. Here, we pose that the IP3R3 isoform is not only linked to proapoptotic ER-mitochondrial Ca2+ transfers but might also be involved in prosurvival signaling.
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Affiliation(s)
- Nicolas Rosa
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut (LKI), Leuven, Belgium
| | - Flore Sneyers
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut (LKI), Leuven, Belgium
| | - Jan B Parys
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut (LKI), Leuven, Belgium
| | - Geert Bultynck
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine and Leuven Kanker Instituut (LKI), Leuven, Belgium.
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27
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The Host Factor Erlin-1 is Required for Efficient Hepatitis C Virus Infection. Cells 2019; 8:cells8121555. [PMID: 31810281 PMCID: PMC6953030 DOI: 10.3390/cells8121555] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 11/28/2019] [Accepted: 11/29/2019] [Indexed: 12/22/2022] Open
Abstract
Development of hepatitis C virus (HCV) infection cell culture systems has permitted the identification of cellular factors that regulate the HCV life cycle. Some of these cellular factors affect steps in the viral life cycle that are tightly associated with intracellular membranes derived from the endoplasmic reticulum (ER). Here, we describe the discovery of erlin-1 protein as a cellular factor that regulates HCV infection. Erlin-1 is a cholesterol-binding protein located in detergent-resistant membranes within the ER. It is implicated in cholesterol homeostasis and the ER-associated degradation pathway. Silencing of erlin-1 protein expression by siRNA led to decreased infection efficiency characterized by reduction in intracellular RNA accumulation, HCV protein expression and virus production. Mechanistic studies revealed that erlin-1 protein is required early in the infection, downstream of cell entry and primary translation, specifically to initiate RNA replication, and later in the infection to support infectious virus production. This study identifies erlin-1 protein as an important cellular factor regulating HCV infection.
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28
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Wagner M, Osborn DPS, Gehweiler I, Nagel M, Ulmer U, Bakhtiari S, Amouri R, Boostani R, Hentati F, Hockley MM, Hölbling B, Schwarzmayr T, Karimiani EG, Kernstock C, Maroofian R, Müller-Felber W, Ozkan E, Padilla-Lopez S, Reich S, Reichbauer J, Darvish H, Shahmohammadibeni N, Tafakhori A, Vill K, Zuchner S, Kruer MC, Winkelmann J, Jamshidi Y, Schüle R. Bi-allelic variants in RNF170 are associated with hereditary spastic paraplegia. Nat Commun 2019; 10:4790. [PMID: 31636353 PMCID: PMC6803694 DOI: 10.1038/s41467-019-12620-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 09/18/2019] [Indexed: 12/11/2022] Open
Abstract
Alterations of Ca2+ homeostasis have been implicated in a wide range of neurodegenerative diseases. Ca2+ efflux from the endoplasmic reticulum into the cytoplasm is controlled by binding of inositol 1,4,5-trisphosphate to its receptor. Activated inositol 1,4,5-trisphosphate receptors are then rapidly degraded by the endoplasmic reticulum-associated degradation pathway. Mutations in genes encoding the neuronal isoform of the inositol 1,4,5-trisphosphate receptor (ITPR1) and genes involved in inositol 1,4,5-trisphosphate receptor degradation (ERLIN1, ERLIN2) are known to cause hereditary spastic paraplegia (HSP) and cerebellar ataxia. We provide evidence that mutations in the ubiquitin E3 ligase gene RNF170, which targets inositol 1,4,5-trisphosphate receptors for degradation, are the likely cause of autosomal recessive HSP in four unrelated families and functionally evaluate the consequences of mutations in patient fibroblasts, mutant SH-SY5Y cells and by gene knockdown in zebrafish. Our findings highlight inositol 1,4,5-trisphosphate signaling as a candidate key pathway for hereditary spastic paraplegias and cerebellar ataxias and thus prioritize this pathway for therapeutic interventions.
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Affiliation(s)
- Matias Wagner
- Institute of Human Genetics, Technische Universität München, Trogerstraße 32, 81675, Munich, Germany
- Institute of Human Genetics, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
- Institut für Neurogenomik, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Daniel P S Osborn
- Genetics Centre, Molecular and Clinical Sciences Institute, St George's University of London, London, UK
| | - Ina Gehweiler
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Otfried-Müller-Str. 27, 72076, Tübingen, Germany
| | - Maike Nagel
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Otfried-Müller-Str. 27, 72076, Tübingen, Germany
| | - Ulrike Ulmer
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Otfried-Müller-Str. 27, 72076, Tübingen, Germany
| | - Somayeh Bakhtiari
- Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, 85016, USA
- Departments of Child Health, Cellular & Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine, Phoenix, AZ, 85004, USA
| | - Rim Amouri
- Neurology Department, Mongi Ben Hmida National Institute of Neurology, Tunis, Tunisia
- Neuroscience Department, Faculty of Medicine of Tunis, University Tunis El Manar, Tunis, Tunisia
| | | | - Faycal Hentati
- Neurology Department, Mongi Ben Hmida National Institute of Neurology, Tunis, Tunisia
- Neuroscience Department, Faculty of Medicine of Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Maryam M Hockley
- Departments of Child Health, Cellular & Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine, Phoenix, AZ, 85004, USA
| | - Benedikt Hölbling
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Otfried-Müller-Str. 27, 72076, Tübingen, Germany
| | - Thomas Schwarzmayr
- Institut für Neurogenomik, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Ehsan Ghayoor Karimiani
- Genetics Centre, Molecular and Clinical Sciences Institute, St George's University of London, London, UK
- Next Generation Genetic Clinic, Mashhad, Iran
| | - Christoph Kernstock
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Reza Maroofian
- Genetics Centre, Molecular and Clinical Sciences Institute, St George's University of London, London, UK
| | - Wolfgang Müller-Felber
- Department of Pediatric Neurology and Developmental Medicine, Ludwig-Maximilians-University of Munich, Lindwurmstraße 4, 80337, Munich, Germany
| | - Ege Ozkan
- Genetics Centre, Molecular and Clinical Sciences Institute, St George's University of London, London, UK
| | - Sergio Padilla-Lopez
- Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, 85016, USA
- Departments of Child Health, Cellular & Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine, Phoenix, AZ, 85004, USA
| | - Selina Reich
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Otfried-Müller-Str. 27, 72076, Tübingen, Germany
| | - Jennifer Reichbauer
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Otfried-Müller-Str. 27, 72076, Tübingen, Germany
| | - Hossein Darvish
- Cancer Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | | | - Abbas Tafakhori
- Iranian Center of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Katharina Vill
- Department of Pediatric Neurology and Developmental Medicine, Ludwig-Maximilians-University of Munich, Lindwurmstraße 4, 80337, Munich, Germany
| | - Stephan Zuchner
- Dr. John T. Macdonald Foundation, Department of Human Genetics, FL33136, Miami, USA
- John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, FL33136, Miami, USA
| | - Michael C Kruer
- Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, 85016, USA
- Departments of Child Health, Cellular & Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine, Phoenix, AZ, 85004, USA
| | - Juliane Winkelmann
- Institute of Human Genetics, Technische Universität München, Trogerstraße 32, 81675, Munich, Germany
- Institut für Neurogenomik, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Yalda Jamshidi
- Genetics Centre, Molecular and Clinical Sciences Institute, St George's University of London, London, UK
| | - Rebecca Schüle
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany.
- German Center for Neurodegenerative Diseases (DZNE), Otfried-Müller-Str. 27, 72076, Tübingen, Germany.
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29
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Lindhout FW, Cao Y, Kevenaar JT, Bodzęta A, Stucchi R, Boumpoutsari MM, Katrukha EA, Altelaar M, MacGillavry HD, Hoogenraad CC. VAP-SCRN1 interaction regulates dynamic endoplasmic reticulum remodeling and presynaptic function. EMBO J 2019; 38:e101345. [PMID: 31441084 PMCID: PMC6792018 DOI: 10.15252/embj.2018101345] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 07/11/2019] [Accepted: 07/17/2019] [Indexed: 01/08/2023] Open
Abstract
In neurons, the continuous and dynamic endoplasmic reticulum (ER) network extends throughout the axon, and its dysfunction causes various axonopathies. However, it remains largely unknown how ER integrity and remodeling modulate presynaptic function in mammalian neurons. Here, we demonstrated that ER membrane receptors VAPA and VAPB are involved in modulating the synaptic vesicle (SV) cycle. VAP interacts with secernin-1 (SCRN1) at the ER membrane via a single FFAT-like motif. Similar to VAP, loss of SCRN1 or SCRN1-VAP interactions resulted in impaired SV cycling. Consistently, SCRN1 or VAP depletion was accompanied by decreased action potential-evoked Ca2+ responses. Additionally, we found that VAP-SCRN1 interactions play an important role in maintaining ER continuity and dynamics, as well as presynaptic Ca2+ homeostasis. Based on these findings, we propose a model where the ER-localized VAP-SCRN1 interactions provide a novel control mechanism to tune ER remodeling and thereby modulate Ca2+ dynamics and SV cycling at presynaptic sites. These data provide new insights into the molecular mechanisms controlling ER structure and dynamics, and highlight the relevance of ER function for SV cycling.
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Affiliation(s)
- Feline W Lindhout
- Department of BiologyCell BiologyUtrecht UniversityUtrechtThe Netherlands
| | - Yujie Cao
- Department of BiologyCell BiologyUtrecht UniversityUtrechtThe Netherlands
| | - Josta T Kevenaar
- Department of BiologyCell BiologyUtrecht UniversityUtrechtThe Netherlands
| | - Anna Bodzęta
- Department of BiologyCell BiologyUtrecht UniversityUtrechtThe Netherlands
| | - Riccardo Stucchi
- Department of BiologyCell BiologyUtrecht UniversityUtrechtThe Netherlands
- Biomolecular Mass Spectrometry and ProteomicsBijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical SciencesUtrecht UniversityUtrechtThe Netherlands
| | | | - Eugene A Katrukha
- Department of BiologyCell BiologyUtrecht UniversityUtrechtThe Netherlands
| | - Maarten Altelaar
- Biomolecular Mass Spectrometry and ProteomicsBijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical SciencesUtrecht UniversityUtrechtThe Netherlands
| | | | - Casper C Hoogenraad
- Department of BiologyCell BiologyUtrecht UniversityUtrechtThe Netherlands
- Department of NeuroscienceGenentech, Inc.South San FranciscoCAUSA
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30
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Bok regulates mitochondrial fusion and morphology. Cell Death Differ 2019; 26:2682-2694. [PMID: 30976095 DOI: 10.1038/s41418-019-0327-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 03/05/2019] [Accepted: 03/25/2019] [Indexed: 12/11/2022] Open
Abstract
Bok (Bcl-2-related ovarian killer) is a member of the Bcl-2 protein family that governs the intrinsic apoptosis pathway, but the cellular role that Bok plays is controversial. Remarkably, endogenous Bok is constitutively bound to inositol 1,4,5-trisphosphate receptors (IP3Rs) and is stabilized by this interaction. Here we report that despite the strong association with IP3Rs, deletion of Bok expression by CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated protein-9 nuclease)-mediated gene editing does not alter calcium mobilization via IP3Rs or calcium influx into the mitochondria. Rather, Bok deletion significantly reduces mitochondrial fusion rate, resulting in mitochondrial fragmentation. This phenotype is reversed by exogenous wild-type Bok and by an IP3R binding-deficient Bok mutant, and may result from a decrease in mitochondrial motility. Bok deletion also enhances mitochondrial spare respiratory capacity and membrane potential. Finally, Bok does not play a major role in apoptotic signaling, since Bok deletion does not alter responsiveness to various apoptotic stimuli. Overall, despite binding to IP3Rs, Bok does not alter IP3R-mediated Ca2+ signaling, but is required to maintain normal mitochondrial fusion, morphology, and bioenergetics.
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31
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Wright FA, Bonzerato CG, Sliter DA, Wojcikiewicz RJH. The erlin2 T65I mutation inhibits erlin1/2 complex-mediated inositol 1,4,5-trisphosphate receptor ubiquitination and phosphatidylinositol 3-phosphate binding. J Biol Chem 2018; 293:15706-15714. [PMID: 30135210 DOI: 10.1074/jbc.ra118.004547] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 07/19/2018] [Indexed: 12/11/2022] Open
Abstract
The erlin1/2 complex is a ∼2-MDa endoplasmic reticulum membrane-located ensemble of the ∼40-kDa type II membrane proteins erlin1 and erlin2. The best defined function of this complex is to mediate the ubiquitination of activated inositol 1,4,5-trisphosphate receptors (IP3Rs) and their subsequent degradation. However, it remains unclear how mutations of the erlin1/2 complex affect its cellular function and cause cellular dysfunction and diseases such as hereditary spastic paraplegia. Here, we used gene editing to ablate erlin1 or erlin2 expression to better define their individual roles in the cell and examined the functional effects of a spastic paraplegia-linked mutation to erlin2 (threonine to isoleucine at position 65; T65I). Our results revealed that erlin2 is the dominant player in mediating the interaction between the erlin1/2 complex and IP3Rs and that the T65I mutation dramatically inhibits this interaction and the ability of the erlin1/2 complex to promote IP3R ubiquitination and degradation. Remarkably, we also discovered that the erlin1/2 complex specifically binds to phosphatidylinositol 3-phosphate, that erlin2 binds this phospholipid much more strongly than does erlin1, that the binding is inhibited by T65I mutation of erlin2, and that multiple determinants within the erlin2 polypeptide comprise the phosphatidylinositol 3-phosphate-binding site. Overall, these results indicate that erlin2 is the primary mediator of the cellular roles of the erlin1/2 complex and that disease-linked mutations of erlin2 can affect both IP3R processing and lipid binding.
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Affiliation(s)
- Forrest A Wright
- From the Department of Pharmacology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York 13210 and
| | - Caden G Bonzerato
- From the Department of Pharmacology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York 13210 and
| | - Danielle A Sliter
- Biochemistry Section, Surgical Neurology Branch, NINDS, National Institutes of Health, Bethesda, Maryland 20892
| | - Richard J H Wojcikiewicz
- From the Department of Pharmacology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York 13210 and
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32
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Hwang J, Qi L. Quality Control in the Endoplasmic Reticulum: Crosstalk between ERAD and UPR pathways. Trends Biochem Sci 2018; 43:593-605. [PMID: 30056836 PMCID: PMC6327314 DOI: 10.1016/j.tibs.2018.06.005] [Citation(s) in RCA: 343] [Impact Index Per Article: 57.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 05/30/2018] [Accepted: 06/11/2018] [Indexed: 01/14/2023]
Abstract
Endoplasmic reticulum (ER)-associated degradation (ERAD) and the unfolded protein response (UPR) are two key quality-control machineries in the cell. ERAD is responsible for the clearance of misfolded proteins in the ER for cytosolic proteasomal degradation, while UPR is activated in response to the accumulation of misfolded proteins. It has long been thought that ERAD is an integral part of UPR because expression of many ERAD genes is controlled by UPR; however, recent studies have suggested that ERAD has a direct role in controlling the protein turnover and abundance of IRE1α, the most conserved UPR sensor. Here, we review recent advances in our understanding of IRE1α activation and propose that UPR and ERAD engage in an intimate crosstalk to define folding capacity and maintain homeostasis in the ER.
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Affiliation(s)
- Jiwon Hwang
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48105, 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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33
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Mitochondria-associated membranes (MAMs) and inflammation. Cell Death Dis 2018; 9:329. [PMID: 29491386 PMCID: PMC5832426 DOI: 10.1038/s41419-017-0027-2] [Citation(s) in RCA: 204] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/26/2017] [Accepted: 09/27/2017] [Indexed: 12/18/2022]
Abstract
The endoplasmic reticulum (ER) and mitochondria are tightly associated with very dynamic platforms termed mitochondria-associated membranes (MAMs). MAMs provide an excellent scaffold for crosstalk between the ER and mitochondria and play a pivotal role in different signaling pathways that allow rapid exchange of biological molecules to maintain cellular health. However, dysfunctions in the ER–mitochondria architecture are associated with pathological conditions and human diseases. Inflammation has emerged as one of the various pathways that MAMs control. Inflammasome components and other inflammatory factors promote the release of pro-inflammatory cytokines that sustain pathological conditions. In this review, we summarize the critical role of MAMs in initiating inflammation in the cellular defense against pathogenic infections and the association of MAMs with inflammation-mediated diseases.
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34
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Moriggi M, Pastorelli L, Torretta E, Tontini GE, Capitanio D, Bogetto SF, Vecchi M, Gelfi C. Contribution of Extracellular Matrix and Signal Mechanotransduction to Epithelial Cell Damage in Inflammatory Bowel Disease Patients: A Proteomic Study. Proteomics 2017; 17. [PMID: 29027377 DOI: 10.1002/pmic.201700164] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/18/2017] [Indexed: 12/14/2022]
Abstract
This study utilizes 2D-DIGE (difference gel etrophoresis), isotope-coded protein labeling and biochemical assays to characterize protein alteration in ulcerative colitis (UC) and Crohn's disease (CD) in human epithelial cell and mucosal biopsies in inflammatory bowel disease (IBD)-affected patients. The aim of this study is to identify the key molecular signatures involved in epithelial cell structure of IBDs. In non-inflamed UC (QUC) keratins, vimentin, and focal adhesion kinase (7) increased, whereas vinculin and de-tyrosinated α-tubulin decreased; inflammation (IUC) exacerbated molecular changes, being collagen type VI alpha 1 chain (COL6A1), tenascin-C and vimentin increased. In non-inflamed CD (QCD), tenascin C, de-tyrosinated α-tubulin, vinculin, FAK, and Rho-associated protein kinase 1 (ROCK1) decreased while vimentin increased. In inflamed CD (ICD), COL6A1, vimentin and integrin alpha 4 increased. In QUC, cell metabolism is characterized by a decrease of the tricarboxylic acid cycle enzymes and a decrease of short/branched chain specific acyl-CoA dehydrogenase, fatty acid synthase, proliferator-activated receptors alpha, and proliferator-activated receptors gamma. In QCD a metabolic rewiring occurs, as suggested by glycerol-3-phosphate dehydrogenase (GPD2), pyruvate dehydrogenase E1 component subunit beta, NADH dehydrogenase [ubiquinone] iron-sulfur protein 3, and 4-trimethylaminobutyraldehyde dehydrogenase increment, while dihydrolipoyl dehydrogenase decreased. Macroautophagy is activated in QUC and IUC, with increased levels of p62, HSC70, major vault protein, myosin heavy chain 9, whereas it is blunted in QCD and ICD. The differing pattern of extracellular matrix, cytoskeletal derangements, cellular metabolism, and autophagy in UC and CD may contribute to the pathophysiological understanding of these disorders and serve as diagnostic markers in IBD patients.
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Affiliation(s)
- Manuela Moriggi
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Luca Pastorelli
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy.,Gastroenterology and Digestive Endoscopy UnitIRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Enrica Torretta
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Gian Eugenio Tontini
- Gastroenterology and Digestive Endoscopy UnitIRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Daniele Capitanio
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | | | - Maurizio Vecchi
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy.,Gastroenterology and Digestive Endoscopy UnitIRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Cecilia Gelfi
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy.,Clinical Proteomics Unit, IRCCS Policlinico San Donato, San Donato Milanese, Italy
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35
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Printsev I, Curiel D, Carraway KL. Membrane Protein Quantity Control at the Endoplasmic Reticulum. J Membr Biol 2017; 250:379-392. [PMID: 27743014 PMCID: PMC5392169 DOI: 10.1007/s00232-016-9931-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 09/28/2016] [Indexed: 02/07/2023]
Abstract
The canonical function of the endoplasmic reticulum-associated degradation (ERAD) system is to enforce quality control among membrane-associated proteins by targeting misfolded secreted, intra-organellar, and intramembrane proteins for degradation. However, increasing evidence suggests that ERAD additionally functions in maintaining appropriate levels of a subset of membrane-associated proteins. In this 'quantity control' capacity, ERAD responds to environmental cues to regulate the proteasomal degradation of specific ERAD substrates according to cellular need. In this review, we discuss in detail seven proteins that are targeted by the ERAD quantity control system. Not surprisingly, ERAD-mediated protein degradation is a key regulatory feature of a variety of ER-resident proteins, including HMG-CoA reductase, cytochrome P450 3A4, IP3 receptor, and type II iodothyronine deiodinase. In addition, the ERAD quantity control system plays roles in maintaining the proper stoichiometry of multi-protein complexes by mediating the degradation of components that are produced in excess of the limiting subunit. Perhaps somewhat unexpectedly, recent evidence suggests that the ERAD quantity control system also contributes to the regulation of plasma membrane-localized signaling receptors, including the ErbB3 receptor tyrosine kinase and the GABA neurotransmitter receptors. For these substrates, a proportion of the newly synthesized yet properly folded receptors are diverted for degradation at the ER, and are unable to traffic to the plasma membrane. Given that receptor abundance or concentration within the plasma membrane plays key roles in determining signaling efficiency, these observations may point to a novel mechanism for modulating receptor-mediated cellular signaling.
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Affiliation(s)
- Ignat Printsev
- Department of Biochemistry and Molecular Medicine, and UC Davis Comprehensive Cancer Center, UC Davis School of Medicine, Research Building III, Room 1100B, 4645 2nd Avenue, Sacramento, CA, 95817, USA
| | - Daniel Curiel
- Department of Biochemistry and Molecular Medicine, and UC Davis Comprehensive Cancer Center, UC Davis School of Medicine, Research Building III, Room 1100B, 4645 2nd Avenue, Sacramento, CA, 95817, USA
| | - Kermit L Carraway
- Department of Biochemistry and Molecular Medicine, and UC Davis Comprehensive Cancer Center, UC Davis School of Medicine, Research Building III, Room 1100B, 4645 2nd Avenue, Sacramento, CA, 95817, USA.
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36
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Regulated Erlin-dependent release of the B12 transmembrane J-protein promotes ER membrane penetration of a non-enveloped virus. PLoS Pathog 2017; 13:e1006439. [PMID: 28614383 PMCID: PMC5484543 DOI: 10.1371/journal.ppat.1006439] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 06/26/2017] [Accepted: 05/30/2017] [Indexed: 12/16/2022] Open
Abstract
The molecular mechanism by which non-enveloped viruses penetrate biological membranes remains enigmatic. The non-enveloped polyomavirus SV40 penetrates the endoplasmic reticulum (ER) membrane to reach the cytosol and cause infection. We previously demonstrated that SV40 creates its own membrane penetration structure by mobilizing select transmembrane proteins to distinct puncta in the ER membrane called foci that likely function as the cytosol entry sites. How these ER membrane proteins reorganize into the foci is unknown. B12 is a transmembrane J-protein that mobilizes into the foci to promote cytosol entry of SV40. Here we identify two closely related ER membrane proteins Erlin1 and Erlin2 (Erlin1/2) as B12-interaction partners. Strikingly, SV40 recruits B12 to the foci by inducing release of this J-protein from Erlin1/2. Our data thus reveal how a non-enveloped virus promotes its own membrane translocation by triggering the release and recruitment of a critical transport factor to the membrane penetration site. Polyomavirus (PyV) is a non-enveloped DNA tumor virus that causes debilitating human diseases especially in immunocompromised individuals. At the cellular level, PyVs such as the simian PyV SV40 must enter a host cell and penetrate the ER membrane to reach the cytosol in order to cause infection. Prior to ER membrane transport, SV40 reorganizes select ER membrane proteins including the J-protein B12 to potential membrane penetration sites on the ER membrane called foci where B12 facilitates virus extraction into the cytosol. How B12 reorganizes into the foci is unclear. Here we find that two closely related ER membrane proteins Erlin1 and Erlin2 (Erlin1/2) bind to B12. During infection, SV40 induces release of this J-protein from Erlin1/2 to enable B12 to reorganize into the foci. Our data reveal how a non-enveloped virus mobilizes a specific ER membrane component to a membrane penetration structure to promote its own membrane transport.
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37
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Li J, Alyamani M, Zhang A, Chang KH, Berk M, Li Z, Zhu Z, Petro M, Magi-Galluzzi C, Taplin ME, Garcia JA, Courtney K, Klein EA, Sharifi N. Aberrant corticosteroid metabolism in tumor cells enables GR takeover in enzalutamide resistant prostate cancer. eLife 2017; 6. [PMID: 28191869 PMCID: PMC5305204 DOI: 10.7554/elife.20183] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 11/14/2016] [Indexed: 01/02/2023] Open
Abstract
Prostate cancer is driven by androgen stimulation of the androgen receptor (AR). The next-generation AR antagonist, enzalutamide, prolongs survival, but resistance and lethal disease eventually prevail. Emerging data suggest that the glucocorticoid receptor (GR) is upregulated in this context, stimulating expression of AR-target genes that permit continued growth despite AR blockade. However, countering this mechanism by administration of GR antagonists is problematic because GR is essential for life. We show that enzalutamide treatment in human models of prostate cancer and patient tissues is accompanied by a ubiquitin E3-ligase, AMFR, mediating loss of 11β-hydroxysteroid dehydrogenase-2 (11β-HSD2), which otherwise inactivates cortisol, sustaining tumor cortisol concentrations to stimulate GR and enzalutamide resistance. Remarkably, reinstatement of 11β-HSD2 expression, or AMFR loss, reverses enzalutamide resistance in mouse xenograft tumors. Together, these findings reveal a surprising metabolic mechanism of enzalutamide resistance that may be targeted with a strategy that circumvents a requirement for systemic GR ablation.
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Affiliation(s)
- Jianneng Li
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States
| | - Mohammad Alyamani
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States.,Department of Chemistry, Cleveland State University, Cleveland, United States
| | - Ao Zhang
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States
| | - Kai-Hsiung Chang
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States
| | - Michael Berk
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States
| | - Zhenfei Li
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States
| | - Ziqi Zhu
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States
| | - Marianne Petro
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States
| | | | - Mary-Ellen Taplin
- Lank Center of Genitourinary Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, United States
| | - Jorge A Garcia
- Department of Hematology and Oncology, Taussig Cancer Institute, Cleveland, United States
| | - Kevin Courtney
- Division of Hematology and Oncology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Eric A Klein
- Department of Urology, Glickman Urological and Kidney Institute, Cleveland, United States
| | - Nima Sharifi
- Department of Cancer Biology, Lerner Research Institute, Cleveland, United States.,Department of Chemistry, Cleveland State University, Cleveland, United States.,Department of Hematology and Oncology, Taussig Cancer Institute, Cleveland, United States.,Department of Urology, Glickman Urological and Kidney Institute, Cleveland, United States
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38
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Ji Y, Kim H, Yang L, Sha H, Roman CA, Long Q, Qi L. The Sel1L-Hrd1 Endoplasmic Reticulum-Associated Degradation Complex Manages a Key Checkpoint in B Cell Development. Cell Rep 2016; 16:2630-2640. [PMID: 27568564 DOI: 10.1016/j.celrep.2016.08.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Revised: 07/06/2016] [Accepted: 07/31/2016] [Indexed: 01/09/2023] Open
Abstract
Endoplasmic reticulum (ER)-associated degradation (ERAD) is a principal mechanism that targets ER-associated proteins for cytosolic proteasomal degradation. Here, our data demonstrate a critical role for the Sel1L-Hrd1 complex, the most conserved branch of ERAD, in early B cell development. Loss of Sel1L-Hrd1 ERAD in B cell precursors leads to a severe developmental block at the transition from large to small pre-B cells. Mechanistically, we show that Sel1L-Hrd1 ERAD selectively recognizes and targets the pre-B cell receptor (pre-BCR) for proteasomal degradation in a BiP-dependent manner. The pre-BCR complex accumulates both intracellularly and at the cell surface in Sel1L-deficient pre-B cells, leading to persistent pre-BCR signaling and pre-B cell proliferation. This study thus implicates ERAD mediated by Sel1L-Hrd1 as a key regulator of B cell development and reveals the molecular mechanism underpinning the transient nature of pre-BCR signaling.
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Affiliation(s)
- Yewei Ji
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Hana Kim
- Graduate Field of Immunology and Infectious Disease, Cornell University, Ithaca, NY 14853, USA
| | - Liu Yang
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Haibo Sha
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Christopher A Roman
- Department of Cell Biology, College of Medicine and Program in Molecular and Cellular Biology, The School of Graduate Studies, State University of New York, Downstate Medical Center at Brooklyn, New York, NY 11203, USA
| | - Qiaoming Long
- Laboratory Animal Research Center, Medical College of Soochow University, Suzhou 215006, Jiangsu, China
| | - Ling Qi
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA; Graduate Field of Immunology and Infectious Disease, Cornell University, Ithaca, NY 14853, USA.
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39
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Schulman JJ, Wright FA, Han X, Zluhan EJ, Szczesniak LM, Wojcikiewicz RJH. The Stability and Expression Level of Bok Are Governed by Binding to Inositol 1,4,5-Trisphosphate Receptors. J Biol Chem 2016; 291:11820-8. [PMID: 27053113 DOI: 10.1074/jbc.m115.711242] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Indexed: 12/31/2022] Open
Abstract
Bok is a member of the Bcl-2 protein family that governs the intrinsic apoptosis pathway, although the role that Bok plays in this pathway is unclear. We have shown previously in cultured cell lines that Bok interacts strongly with inositol 1,4,5-trisphosphate receptors (IP3Rs), suggesting that it may contribute to the structural integrity or stability of IP3R tetramers. Here we report that Bok is similarly IP3R-assocated in mouse tissues, that essentially all cellular Bok is IP3R bound, that it is the helical nature of the Bok BH4 domain, rather than specific amino acids, that mediates binding to IP3Rs, that Bok is dramatically stabilized by binding to IP3Rs, that unbound Bok is ubiquitinated and degraded by the proteasome, and that binding to IP3Rs limits the pro-apoptotic effect of overexpressed Bok. Agents that stimulate IP3R activity, apoptosis, phosphorylation, and endoplasmic reticulum stress did not trigger the dissociation of mature Bok from IP3Rs or Bok degradation, indicating that the role of proteasome-mediated Bok degradation is to destroy newly synthesized Bok that is not IP3R associated. The existence of this unexpected proteolytic mechanism that is geared toward restricting Bok to that which is bound to IP3Rs, implies that unbound Bok is deleterious to cell viability and helps explain the current uncertainty regarding the cellular role of Bok.
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Affiliation(s)
- Jacqualyn J Schulman
- From the Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York 13210
| | - Forrest A Wright
- From the Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York 13210
| | - Xiaobing Han
- From the Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York 13210
| | - Eric J Zluhan
- From the Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York 13210
| | - Laura M Szczesniak
- From the Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York 13210
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40
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Wright FA, Wojcikiewicz RJH. Chapter 4 - Inositol 1,4,5-Trisphosphate Receptor Ubiquitination. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 141:141-59. [PMID: 27378757 DOI: 10.1016/bs.pmbts.2016.02.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Inositol 1,4,5-trisphosphate receptors (IP3Rs) are large (∼300kDa) proteins that associate into tetrameric ion channels in the endoplasmic reticulum (ER) membrane. Activation and opening of the channel upon binding of IP3 and Ca(2+) allows the flow of Ca(2+) ions from stores within the ER lumen to the cytosol, thereby promoting a number of Ca(2+)-dependent cellular events, such as secretion, neurotransmitter release, and cell division. Intriguingly, it appears that the same conformational change that IP3Rs undergo during activation makes them a target for degradation by the ubiquitin-proteasome pathway and that this mode of processing allows the cell to tune its internal Ca(2+) response to extracellular signals. Here, we review recent studies showing that activated IP3Rs interact with an array of proteins that mediate their degradation, that IP3Rs are modified by a complex array of ubiquitin conjugates, that this ubiquitination and degradation functions to regulate IP3-mediated Ca(2+) responses in the cell, and that mutations to different proteins involved in IP3R degradation result in a set of similar diseases.
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Affiliation(s)
- F A Wright
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, United States
| | - R J H Wojcikiewicz
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY, United States.
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41
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Howe V, Sharpe LJ, Alexopoulos SJ, Kunze SV, Chua NK, Li D, Brown AJ. Cholesterol homeostasis: How do cells sense sterol excess? Chem Phys Lipids 2016; 199:170-178. [PMID: 26993747 DOI: 10.1016/j.chemphyslip.2016.02.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 02/27/2016] [Indexed: 12/23/2022]
Abstract
Cholesterol is vital in mammals, but toxic in excess. Consequently, elaborate molecular mechanisms have evolved to maintain this sterol within narrow limits. How cells sense excess cholesterol is an intriguing area of research. Cells sense cholesterol, and other related sterols such as oxysterols or cholesterol synthesis intermediates, and respond to changing levels through several elegant mechanisms of feedback regulation. Cholesterol sensing involves both direct binding of sterols to the homeostatic machinery located in the endoplasmic reticulum (ER), and indirect effects elicited by sterol-dependent alteration of the physical properties of membranes. Here, we examine the mechanisms employed by cells to maintain cholesterol homeostasis.
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Affiliation(s)
- Vicky Howe
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Laura J Sharpe
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Stephanie J Alexopoulos
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Sarah V Kunze
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Ngee Kiat Chua
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Dianfan Li
- National Center for Protein Sciences, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Andrew J Brown
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia.
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Prole DL, Taylor CW. Inositol 1,4,5-trisphosphate receptors and their protein partners as signalling hubs. J Physiol 2016; 594:2849-66. [PMID: 26830355 PMCID: PMC4887697 DOI: 10.1113/jp271139] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 11/06/2015] [Indexed: 01/26/2023] Open
Abstract
Inositol 1,4,5‐trisphosphate receptors (IP3Rs) are expressed in nearly all animal cells, where they mediate the release of Ca2+ from intracellular stores. The complex spatial and temporal organization of the ensuing intracellular Ca2+ signals allows selective regulation of diverse physiological responses. Interactions of IP3Rs with other proteins contribute to the specificity and speed of Ca2+ signalling pathways, and to their capacity to integrate information from other signalling pathways. In this review, we provide a comprehensive survey of the proteins proposed to interact with IP3Rs and the functional effects that these interactions produce. Interacting proteins can determine the activity of IP3Rs, facilitate their regulation by multiple signalling pathways and direct the Ca2+ that they release to specific targets. We suggest that IP3Rs function as signalling hubs through which diverse inputs are processed and then emerge as cytosolic Ca2+ signals.
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Affiliation(s)
- David L Prole
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD, UK
| | - Colin W Taylor
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD, UK
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43
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Cui Y, Gu X. Proteomic changes of the porcine small intestine in response to chronic heat stress. J Mol Endocrinol 2015; 55:277-93. [PMID: 26416815 PMCID: PMC4632496 DOI: 10.1530/jme-15-0161] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Revised: 08/26/2015] [Accepted: 09/28/2015] [Indexed: 01/24/2023]
Abstract
Acute heat stress (HS) negatively affects intestinal integrity and barrier function. In contrast, chronic mild HS poses a distinct challenge to animals. Therefore, this study integrates biochemical, histological and proteomic approaches to investigate the effects of chronic HS on the intestine in finishing pigs. Castrated male crossbreeds (79.00 ± 1.50 kg BW) were subjected to either thermal neutral (TN, 21 °C; 55% ± 5% humidity; n=8) or HS conditions (30 °C; 55% ± 5% humidity; n=8) for 3 weeks. The pigs were sacrificed after 3 weeks of high environmental exposure and the plasma hormones, the intestinal morphology, integrity, and protein profiles of the jejunum mucosa were determined. Chronic HS reduced the free triiodothyronine (FT3) and GH levels. HS damaged intestinal morphology, increased plasma d-lactate concentrations and decreased alkaline phosphatase activity of intestinal mucosa. Proteome analysis of the jejunum mucosa was conducted by 2D gel electrophoresis and mass spectrometry. Fifty-three intestinal proteins were found to be differentially abundant, 18 of which were related to cell structure and motility, and their changes in abundance could comprise intestinal integrity and function. The down-regulation of proteins involved in tricarboxylic acid cycle (TCA cycle), electron transport chain (ETC), and oxidative phosphorylation suggested that chronic HS impaired energy metabolism and thus induced oxidative stress. Moreover, the changes of ten proteins in abundance related to stress response and defense indicated pigs mediated long-term heat exposure and counteracted its negative effects of heat exposure. These findings have important implications for understanding the effect of chronic HS on intestines.
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Affiliation(s)
- Yanjun Cui
- State Key Laboratory of Animal NutritionInstitute of Animal Sciences, Chinese Academy of Agricultural Science, Beijing 100193, People's Republic of China
| | - Xianhong Gu
- State Key Laboratory of Animal NutritionInstitute of Animal Sciences, Chinese Academy of Agricultural Science, Beijing 100193, People's Republic of China
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44
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Zhang X, Cai J, Zheng Z, Polin L, Lin Z, Dandekar A, Li L, Sun F, Finley RL, Fang D, Yang ZQ, Zhang K. A novel ER-microtubule-binding protein, ERLIN2, stabilizes Cyclin B1 and regulates cell cycle progression. Cell Discov 2015; 1:15024. [PMID: 27462423 PMCID: PMC4860859 DOI: 10.1038/celldisc.2015.24] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 07/10/2015] [Indexed: 12/11/2022] Open
Abstract
The gene encoding endoplasmic reticulum (ER) lipid raft-associated protein 2 (ERLIN2) is amplified in human breast cancers. ERLIN2 gene mutations were also found to be associated with human childhood progressive motor neuron diseases. Yet, an understanding of the physiological function and mechanism for ERLIN2 remains elusive. In this study, we reveal that ERLIN2 is a spatially and temporally regulated ER–microtubule-binding protein that has an important role in cell cycle progression by interacting with and stabilizing the mitosis-promoting factors. Whereas ERLIN2 is highly expressed in aggressive human breast cancers, during normal development ERLIN2 is expressed at the postnatal stage and becomes undetectable in adulthood. ERLIN2 interacts with the microtubule component α-tubulin, and this interaction is maximal during the cell cycle G2/M phase where ERLIN2 simultaneously interacts with the mitosis-promoting complex Cyclin B1/Cdk1. ERLIN2 facilitates K63-linked ubiquitination and stabilization of Cyclin B1 protein in G2/M phase. Downregulation of ERLIN2 results in cell cycle arrest, represses breast cancer proliferation and malignancy and increases sensitivity of breast cancer cells to anticancer drugs. In summary, our study revealed a novel ER–microtubule-binding protein, ERLIN2, which interacts with and stabilizes mitosis-promoting factors to regulate cell cycle progression associated with human breast cancer malignancy.
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Affiliation(s)
- Xuebao Zhang
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine , Detroit, MI, USA
| | - Juan Cai
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine , Detroit, MI, USA
| | - Ze Zheng
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine , Detroit, MI, USA
| | - Lisa Polin
- Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA; Department of Oncology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Zhenghong Lin
- Department of Pathology, Northwestern University Feinberg School of Medicine , Chicago, IL, USA
| | - Aditya Dandekar
- Department of Immunology and Microbiology, Wayne State University School of Medicine , Detroit, MI, USA
| | - Li Li
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA; Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
| | - Fei Sun
- Department of Physiology, Wayne State University School of Medicine , Chicago, IL, USA
| | - Russell L Finley
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA; Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA; Department of Biochemistry and Molecular Biology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Deyu Fang
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Zeng-Quan Yang
- Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA; Department of Oncology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Kezhong Zhang
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA; Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA; Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI, USA
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45
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Williamson CD, Wong DS, Bozidis P, Zhang A, Colberg-Poley AM. Isolation of Endoplasmic Reticulum, Mitochondria, and Mitochondria-Associated Membrane and Detergent Resistant Membrane Fractions from Transfected Cells and from Human Cytomegalovirus-Infected Primary Fibroblasts. ACTA ACUST UNITED AC 2015; 68:3.27.1-3.27.33. [PMID: 26331984 DOI: 10.1002/0471143030.cb0327s68] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Increasingly mechanistic virology studies require dependable and sensitive methods for isolating purified organelles containing functional cellular sub-domains. The mitochondrial network is, in part, closely apposed to the endoplasmic reticulum (ER). The mitochondria-associated membrane (MAM) fraction provides direct physical contact between the ER and mitochondria. Characterization of the dual localization and trafficking of human cytomegalovirus (HCMV) UL37 proteins required establishing protocols in which the ER and mitochondria could be reliably separated. Because of its documented role in lipid and ceramide transfer from the ER to mitochondria, a method to purify MAM from infected cells was also developed. Two robust procedures were developed to efficiently isolate mitochondria, ER, and MAM fractions while providing substantial protein yields from HCMV-infected primary fibroblasts and from transfected HeLa cells. Furthermore, this unit includes protocols for isolation of detergent resistant membranes from subcellular fractions as well as techniques that allow visualization of the mitochondrial network disruption that occurs in permissively infected cells by their optimal resolution in Percoll gradients.
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Affiliation(s)
- Chad D Williamson
- Center for Genetic Medicine Research, Children's Research Institute, Washington, D.C.,Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Daniel S Wong
- Cellular and Molecular Physiology Program, Sackler School for Graduate Biomedical Sciences, Tufts University, Boston, Massachusetts
| | - Petros Bozidis
- Laboratory of Microbiology, Department of Medicine, School of Health Sciences, University of Ioannina, Ioannina, Greece
| | - Aiping Zhang
- Center for Genetic Medicine Research, Children's Research Institute, Washington, D.C
| | - Anamaris M Colberg-Poley
- Center for Genetic Medicine Research, Children's Research Institute, Washington, D.C.,Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, D.C.,Department of Biochemistry and Molecular Medicine, George Washington University School of Medicine and Health Sciences, Washington, D.C.,Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, D.C
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46
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Yang B, Qu M, Wang R, Chatterton JE, Liu XB, Zhu B, Narisawa S, Millan JL, Nakanishi N, Swoboda K, Lipton SA, Zhang D. The critical role of membralin in postnatal motor neuron survival and disease. eLife 2015; 4. [PMID: 25977983 PMCID: PMC4460860 DOI: 10.7554/elife.06500] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 05/15/2015] [Indexed: 12/11/2022] Open
Abstract
Hitherto, membralin has been a protein of unknown function. Here, we show that membralin mutant mice manifest a severe and early-onset motor neuron disease in an autosomal recessive manner, dying by postnatal day 5–6. Selective death of lower motor neurons, including those innervating the limbs, intercostal muscles, and diaphragm, is predominantly responsible for this fatal phenotype. Neural expression of a membralin transgene completely rescues membralin mutant mice. Mechanistically, we show that membralin interacts with Erlin2, an endoplasmic reticulum (ER) membrane protein that is located in lipid rafts and known to be important in ER-associated protein degradation (ERAD). Accordingly, the degradation rate of ERAD substrates is attenuated in cells lacking membralin. Membralin mutations or deficiency in mouse models induces ER stress, rendering neurons more vulnerable to cell death. Our study reveals a critical role of membralin in motor neuron survival and suggests a novel mechanism for early-onset motor neuron disease. DOI:http://dx.doi.org/10.7554/eLife.06500.001 As new proteins are built inside a cell, many will pass into a structure called the endoplasmic reticulum for processing. There, the proteins are folded into the specific three-dimensional shapes that allow them to carry out their respective jobs. Sometimes the folding process goes awry, leading to a build-up of unfolded proteins that stress the endoplasmic reticulum and can kill the cell. Brain cells are particularly vulnerable to death from endoplasmic reticulum stress. To combat a deadly build-up of unfolded proteins, each cell has systems that respond when the endoplasmic reticulum is under stress. Unchecked stress on the endoplasmic reticulum has been linked to diseases like amyotrophic lateral sclerosis (called ALS for short). In diseases like ALS, the nerve cells that control muscle movements gradually die off, causing a loss of muscle control and eventually death. Scientists suspect that these nerve cells (called motor neurons) are particularly sensitive to endoplasmic reticulum stress because they are highly active. Drugs that help counteract stress on the endoplasmic reticulum extend the lives of mice with motor neuron disease, suggesting this may be a useful strategy for treating such diseases in humans. Now, Yang, Qu et al. identify a new protein that appears necessary for a healthy endoplasmic reticulum. Mice that lack the gene for a protein called membralin die within five or six days after birth because their motor neurons die off. Further experiments showed that re-introducing membralin in their nervous system can rescue these membralin-deficient mice. Yang, Qu et al. found that membralin interacts with another protein that helps eliminate poorly folded or unfolded proteins in the endoplasmic reticulum, and thus relieves stress on the cell. Mutations in this endoplasmic reticulum stress response protein have previously been linked to motor neuron diseases. The motor neurons in membralin-deficient mice show signs of endoplasmic reticulum stress and are extra vulnerable to chemicals that induce protein misfolding. Together, the experiments show membralin plays an important role in mitigating stress on the endoplasmic reticulum. More studies of mice lacking membralin may help explain why the endoplasmic reticulum stress increases in motor neuron diseases and may point to possible treatments. DOI:http://dx.doi.org/10.7554/eLife.06500.002
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Affiliation(s)
- Bo Yang
- Neuroscience and Aging Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Mingliang Qu
- Neuroscience and Aging Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Rengang Wang
- Neuroscience and Aging Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Jon E Chatterton
- Neuroscience and Aging Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Xiao-Bo Liu
- Electron Microscopy Laboratory, Department of Pathology and Laboratory Medicine, School of Medicine, University of California, Davis, Davis, United States
| | - Bing Zhu
- Neuroscience and Aging Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Sonoko Narisawa
- Sanford Children's Health Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Jose Luis Millan
- Sanford Children's Health Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Nobuki Nakanishi
- Neuroscience and Aging Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Kathryn Swoboda
- Department of Neurology, Massachusetts General Hospital, , Boston, United States
| | - Stuart A Lipton
- Neuroscience and Aging Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
| | - Dongxian Zhang
- Neuroscience and Aging Research Center, Sanford-Burnham Medical Research Institute, La Jolla, United States
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47
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Wright FA, Lu JP, Sliter DA, Dupré N, Rouleau GA, Wojcikiewicz RJH. A Point Mutation in the Ubiquitin Ligase RNF170 That Causes Autosomal Dominant Sensory Ataxia Destabilizes the Protein and Impairs Inositol 1,4,5-Trisphosphate Receptor-mediated Ca2+ Signaling. J Biol Chem 2015; 290:13948-57. [PMID: 25882839 DOI: 10.1074/jbc.m115.655043] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Indexed: 12/11/2022] Open
Abstract
RNF170 is an endoplasmic reticulum membrane ubiquitin ligase that contributes to the ubiquitination of activated inositol 1,4,5-trisphosphate (IP3) receptors, and also, when point mutated (arginine to cysteine at position 199), causes autosomal dominant sensory ataxia (ADSA), a disease characterized by neurodegeneration in the posterior columns of the spinal cord. Here we demonstrate that this point mutation inhibits RNF170 expression and signaling via IP3 receptors. Inhibited expression of mutant RNF170 was seen in cells expressing exogenous RNF170 constructs and in ADSA lymphoblasts, and appears to result from enhanced RNF170 autoubiquitination and proteasomal degradation. The basis for these effects was probed via additional point mutations, revealing that ionic interactions between charged residues in the transmembrane domains of RNF170 are required for protein stability. In ADSA lymphoblasts, platelet-activating factor-induced Ca(2+) mobilization was significantly impaired, whereas neither Ca(2+) store content, IP3 receptor levels, nor IP3 production were altered, indicative of a functional defect at the IP3 receptor locus, which may be the cause of neurodegeneration. CRISPR/Cas9-mediated genetic deletion of RNF170 showed that RNF170 mediates the addition of all of the ubiquitin conjugates known to become attached to activated IP3 receptors (monoubiquitin and Lys(48)- and Lys(63)-linked ubiquitin chains), and that wild-type and mutant RNF170 have apparently identical ubiquitin ligase activities toward IP3 receptors. Thus, the Ca(2+) mobilization defect seen in ADSA lymphoblasts is apparently not due to aberrant IP3 receptor ubiquitination. Rather, the defect likely reflects abnormal ubiquitination of other substrates, or adaptation to the chronic reduction in RNF170 levels.
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Affiliation(s)
- Forrest A Wright
- From the Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York 13210
| | - Justine P Lu
- From the Department of Pharmacology, SUNY Upstate Medical University, Syracuse, New York 13210
| | | | - Nicolas Dupré
- the Neuromuscular and Neurogenetic Disease Clinic, CHU de Québec, Laval University, Quebec City, Quebec G1J 1Z4, Canada, and
| | - Guy A Rouleau
- the Montreal Neurological Institute and Hospital and Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec H3A 2B4, Canada
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48
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Superresolution imaging of viral protein trafficking. Med Microbiol Immunol 2015; 204:449-60. [PMID: 25724304 DOI: 10.1007/s00430-015-0395-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 02/13/2015] [Indexed: 12/25/2022]
Abstract
The endoplasmic reticulum (ER) membrane is closely apposed to the outer mitochondrial membrane (OMM), which facilitates communication between these organelles. These contacts, known as mitochondria-associated membranes (MAM), facilitate calcium signaling, lipid transfer, as well as antiviral and stress responses. How cellular proteins traffic to the MAM, are distributed therein, and interact with ER and mitochondrial proteins are subject of great interest. The human cytomegalovirus UL37 exon 1 protein or viral mitochondria-localized inhibitor of apoptosis (vMIA) is crucial for viral growth. Upon synthesis at the ER, vMIA traffics to the MAM and OMM, where it reprograms the organization and function of these compartments. vMIA significantly changes the abundance of cellular proteins at the MAM and OMM, including proteins that regulate calcium homeostasis and cell death. Through the use of superresolution imaging, we have shown that vMIA is distributed at the OMM in nanometer scale clusters. This is similar to the clusters reported for the mitochondrial calcium channel, VDAC, as well as electron transport chain, translocase of the OMM complex, and mitochondrial inner membrane organizing system components. Thus, aside from addressing how vMIA targets the MAM and regulates survival of infected cells, biochemical studies and superresolution imaging of vMIA offer insights into the formation, organization, and functioning of MAM. Here, we discuss these insights into trafficking, function, and organization of vMIA at the MAM and OMM and discuss how the use of superresolution imaging is contributing to the study of the formation and trafficking of viruses.
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49
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Quantitative Proteomics and Lipidomics Analysis of Endoplasmic Reticulum of Macrophage Infected with Mycobacterium tuberculosis. INTERNATIONAL JOURNAL OF PROTEOMICS 2015; 2015:270438. [PMID: 25785198 PMCID: PMC4345262 DOI: 10.1155/2015/270438] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 01/21/2015] [Accepted: 01/23/2015] [Indexed: 11/17/2022]
Abstract
Even though endoplasmic reticulum (ER) stress associated with mycobacterial infection has been well studied, the molecular basis of ER as a crucial organelle to determine the fate of Mtb is yet to be established. Here, we have studied the ability of Mtb to manipulate the ultrastructural architecture of macrophage ER and found that the ER-phenotypes associated with virulent (H37Rv) and avirulent (H37Ra) strains were different: a rough ER (RER) with the former against a smooth ER (SER) with the later. Further, the functional attributes of these changes were probed by MS-based quantitative proteomics (133 ER proteins) and lipidomics (8 phospholipids). Our omics approaches not only revealed the host pathogen cross-talk but also emphasized how precisely Mtb uses proteins and lipids in combination to give rise to characteristic ER-phenotypes. H37Ra-infected macrophages increased the cytosolic Ca2+ levels by attenuating the ATP2A2 protein and simultaneous induction of PC/PE expression to facilitate apoptosis. However, H37Rv inhibited apoptosis and further controlled the expression of EST-1 and AMRP proteins to disturb cholesterol homeostasis resulting in sustained infection. This approach offers the potential to decipher the specific roles of ER in understanding the cell biology of mycobacterial infection with special reference to the impact of host response.
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50
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Sun L, Hartson SD, Matts RL. Identification of proteins associated with Aha1 in HeLa cells by quantitative proteomics. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1854:365-80. [PMID: 25614414 DOI: 10.1016/j.bbapap.2015.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 12/20/2014] [Accepted: 01/09/2015] [Indexed: 01/17/2023]
Abstract
The identification of the activator of heat shock protein 90 (Hsp90) ATPase's (Aha1) protein-protein interaction (PPI) network will provide critical insights into the relationship of Aha1 with multi-molecular complexes and shed light onto Aha1's interconnections with Hsp90-regulated biological functions. Flag-tagged Aha1 was over-expressed in HeLa cells and isolated by anti-Flag affinity pull downs, followed by trypsin digestion and identification co-adsorbing proteins by liquid chromatography-tandem mass spectroscopy (LC-MS/MS). A probability-based identification of Aha1 PPIs was generated from the LC-MS/MS analysis by using a relative quantification strategy, spectral counting (SC). By comparing the SC-based protein levels between Aha1 pull-down samples and negative controls, 164 Aha1-interacting proteins were identified that were quantitatively enriched in the pull-down samples over the controls. The identified Aha1-interacting proteins are involved in a wide number of intracellular bioprocesses, including DNA maintenance, chromatin structure, RNA processing, translation, nucleocytoplasmic and vesicle transport, among others. The interactions of 33 of the identified proteins with Aha1 were further confirmed by Western blotting, demonstrating the reliability of our affinity-purification-coupled quantitative SC-MS strategy. Our proteomic data suggests that Aha1 may participate in diverse biological pathways to facilitate Hsp90 chaperone functions in response to stress.
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Affiliation(s)
- Liang Sun
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Steven D Hartson
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Robert L Matts
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA.
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