1
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Connelly EM, Rintala-Dempsey AC, Gundogdu M, Freeman EA, Koszela J, Aguirre JD, Zhu G, Kämäräinen O, Tadayon R, Walden H, Shaw GS. Capturing the catalytic intermediates of parkin ubiquitination. Proc Natl Acad Sci U S A 2024; 121:e2403114121. [PMID: 39078678 PMCID: PMC11317638 DOI: 10.1073/pnas.2403114121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 06/24/2024] [Indexed: 07/31/2024] Open
Abstract
Parkin is an E3 ubiquitin ligase implicated in early-onset forms of Parkinson's disease. It catalyzes a transthiolation reaction by accepting ubiquitin (Ub) from an E2 conjugating enzyme, forming a short-lived thioester intermediate, and transfers Ub to mitochondrial membrane substrates to signal mitophagy. A major impediment to the development of Parkinsonism therapeutics is the lack of structural and mechanistic detail for the essential, short-lived transthiolation intermediate. It is not known how Ub is recognized by the catalytic Rcat domain in parkin that enables Ub transfer from an E2~Ub conjugate to the catalytic site and the structure of the transthiolation complex is undetermined. Here, we capture the catalytic intermediate for the Rcat domain of parkin in complex with ubiquitin (Rcat-Ub) and determine its structure using NMR-based chemical shift perturbation experiments. We show that a previously unidentified α-helical region near the Rcat domain is unmasked as a recognition motif for Ub and guides the C-terminus of Ub toward the parkin catalytic site. Further, we apply a combination of guided AlphaFold modeling, chemical cross-linking, and single turnover assays to establish and validate a model of full-length parkin in complex with UbcH7, its donor Ub, and phosphoubiquitin, trapped in the process of transthiolation. Identification of this catalytic intermediate and orientation of Ub with respect to the Rcat domain provides important structural insights into Ub transfer by this E3 ligase and explains how the previously enigmatic Parkinson's pathogenic mutation T415N alters parkin activity.
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Affiliation(s)
- Elizabeth M. Connelly
- Department of Biochemistry, The University of Western Ontario, London, ONN6A 5C1, Canada
| | | | - Mehmet Gundogdu
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, GlasgowG12 8QQ, UK
| | - E. Aisha Freeman
- Department of Biochemistry, The University of Western Ontario, London, ONN6A 5C1, Canada
| | - Joanna Koszela
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, GlasgowG12 8QQ, UK
| | - Jacob D. Aguirre
- Department of Biochemistry, The University of Western Ontario, London, ONN6A 5C1, Canada
| | - Grace Zhu
- Department of Biochemistry, The University of Western Ontario, London, ONN6A 5C1, Canada
| | - Outi Kämäräinen
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, GlasgowG12 8QQ, UK
| | - Roya Tadayon
- Department of Biochemistry, The University of Western Ontario, London, ONN6A 5C1, Canada
| | - Helen Walden
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, GlasgowG12 8QQ, UK
| | - Gary S. Shaw
- Department of Biochemistry, The University of Western Ontario, London, ONN6A 5C1, Canada
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2
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Fote GM, Eapen VV, Lim RG, Yu C, Salazar L, McClure NR, McKnight J, Nguyen TB, Heath MC, Lau AL, Villamil MA, Miramontes R, Kratter IH, Finkbeiner S, Reidling JC, Paulo JA, Kaiser P, Huang L, Housman DE, Thompson LM, Steffan JS. Huntingtin contains an ubiquitin-binding domain and regulates lysosomal targeting of mitochondrial and RNA-binding proteins. Proc Natl Acad Sci U S A 2024; 121:e2319091121. [PMID: 39074279 PMCID: PMC11317567 DOI: 10.1073/pnas.2319091121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 06/20/2024] [Indexed: 07/31/2024] Open
Abstract
Understanding the normal function of the Huntingtin (HTT) protein is of significance in the design and implementation of therapeutic strategies for Huntington's disease (HD). Expansion of the CAG repeat in the HTT gene, encoding an expanded polyglutamine (polyQ) repeat within the HTT protein, causes HD and may compromise HTT's normal activity contributing to HD pathology. Here, we investigated the previously defined role of HTT in autophagy specifically through studying HTT's association with ubiquitin. We find that HTT interacts directly with ubiquitin in vitro. Tandem affinity purification was used to identify ubiquitinated and ubiquitin-associated proteins that copurify with a HTT N-terminal fragment under basal conditions. Copurification is enhanced by HTT polyQ expansion and reduced by mimicking HTT serine 421 phosphorylation. The identified HTT-interacting proteins include RNA-binding proteins (RBPs) involved in mRNA translation, proteins enriched in stress granules, the nuclear proteome, the defective ribosomal products (DRiPs) proteome and the brain-derived autophagosomal proteome. To determine whether the proteins interacting with HTT are autophagic targets, HTT knockout (KO) cells and immunoprecipitation of lysosomes were used to investigate autophagy in the absence of HTT. HTT KO was associated with reduced abundance of mitochondrial proteins in the lysosome, indicating a potential compromise in basal mitophagy, and increased lysosomal abundance of RBPs which may result from compensatory up-regulation of starvation-induced macroautophagy. We suggest HTT is critical for appropriate basal clearance of mitochondrial proteins and RBPs, hence reduced HTT proteostatic function with mutation may contribute to the neuropathology of HD.
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Affiliation(s)
- Gianna M. Fote
- Department of Biological Chemistry, UC Irvine School of Medicine, Irvine, CA92697
- Department of Neurological Surgery, UC Irvine School of Medicine, Orange, CA92868
| | - Vinay V. Eapen
- Department of Cell Biology, Harvard Medical School, Boston, MA02115
- Casma Therapeutics, Cambridge, MA02139
| | - Ryan G. Lim
- The University of California Irvine Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA92697
| | - Clinton Yu
- Department of Physiology and Biophysics, University of California, Irvine, CA92697
| | - Lisa Salazar
- Department of Psychiatry and Human Behavior, UC Irvine School of Medicine, Orange, CA92868
| | - Nicolette R. McClure
- Department of Neurobiology and Behavior, University of California, Irvine, CA92697
| | - Jharrayne McKnight
- Department of Neurobiology and Behavior, University of California, Irvine, CA92697
| | - Thai B. Nguyen
- Department of Neurobiology and Behavior, University of California, Irvine, CA92697
| | - Marie C. Heath
- Department of Neurobiology and Behavior, University of California, Irvine, CA92697
| | - Alice L. Lau
- Department of Psychiatry and Human Behavior, UC Irvine School of Medicine, Orange, CA92868
| | - Mark A. Villamil
- Department of Biological Chemistry, UC Irvine School of Medicine, Irvine, CA92697
| | - Ricardo Miramontes
- Department of Psychiatry and Human Behavior, UC Irvine School of Medicine, Orange, CA92868
| | - Ian H. Kratter
- Center for Systems and Therapeutics, Gladstone Institutes, San Francisco, CA94158
- Stanford Brain Stimulation Lab, Stanford, CA94304
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA94304
| | - Steven Finkbeiner
- Center for Systems and Therapeutics, Gladstone Institutes, San Francisco, CA94158
- Department of Physiology, University of California, San Francisco, CA94158
- Department of Neurology, University of California, San Francisco, CA94158
| | - Jack C. Reidling
- The University of California Irvine Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA92697
| | - Joao A. Paulo
- Department of Cell Biology, Harvard Medical School, Boston, MA02115
| | - Peter Kaiser
- Department of Biological Chemistry, UC Irvine School of Medicine, Irvine, CA92697
| | - Lan Huang
- Department of Physiology and Biophysics, University of California, Irvine, CA92697
| | - David E. Housman
- Koch Institute for Integrative Cancer Research, The Massachusetts Institute of Technology, Cambridge, MA02139
| | - Leslie M. Thompson
- Department of Biological Chemistry, UC Irvine School of Medicine, Irvine, CA92697
- The University of California Irvine Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA92697
- Department of Psychiatry and Human Behavior, UC Irvine School of Medicine, Orange, CA92868
- Department of Neurobiology and Behavior, University of California, Irvine, CA92697
- Center for Epigenetics and Metabolism, University of California, Irvine School of Medicine, University of California, Irvine, CA92697
| | - Joan S. Steffan
- The University of California Irvine Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA92697
- Department of Psychiatry and Human Behavior, UC Irvine School of Medicine, Orange, CA92868
- Center for Epigenetics and Metabolism, University of California, Irvine School of Medicine, University of California, Irvine, CA92697
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3
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Koszela J, Rintala-Dempsey A, Salzano G, Pimenta V, Kamarainen O, Gabrielsen M, Parui AL, Shaw GS, Walden H. A substrate-interacting region of Parkin directs ubiquitination of the mitochondrial GTPase Miro1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.03.597144. [PMID: 38895334 PMCID: PMC11185606 DOI: 10.1101/2024.06.03.597144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Mutations in the gene encoding for the E3 ubiquitin ligase Parkin have been linked to early-onset Parkinson's disease. Besides many other cellular roles, Parkin is involved in clearance of damaged mitochondria via mitophagy - a process of particular importance in dopaminergic neurons. Upon mitochondrial damage, Parkin accumulates at the outer mitochondrial membrane and is activated, leading to ubiquitination of many mitochondrial substrates and recruitment of mitophagy effectors. While the activation mechanisms of autoinhibited Parkin have been extensively studied, it remains unknown how Parkin recognises its substrates for ubiquitination, and no substrate interaction site in Parkin has been reported. Here, we identify a conserved region in the flexible linker between the Ubl and RING0 domains of Parkin, which is indispensable for Parkin interaction with the mitochondrial GTPase Miro1. Our results explain the preferential targeting and ubiquitination of Miro1 by Parkin and provide a biochemical explanation for the presence of Parkin at the mitochondrial membrane prior to activation induced by mitochondrial damage. Our findings are important for understanding mitochondrial homeostasis and may inspire new therapeutic avenues for Parkinson's disease.
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Affiliation(s)
- Joanna Koszela
- School of Molecular Biosciences, University of Glasgow, Glasgow, UK
| | - Anne Rintala-Dempsey
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
| | | | - Viveka Pimenta
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
| | - Outi Kamarainen
- School of Molecular Biosciences, University of Glasgow, Glasgow, UK
| | - Mads Gabrielsen
- Integrated Protein Analysis, Shared Research Facilities, University of Glasgow, Glasgow, UK
| | - Aasna L Parui
- School of Molecular Biosciences, University of Glasgow, Glasgow, UK
| | - Gary S Shaw
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
| | - Helen Walden
- School of Molecular Biosciences, University of Glasgow, Glasgow, UK
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4
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Clausen L, Okarmus J, Voutsinos V, Meyer M, Lindorff-Larsen K, Hartmann-Petersen R. PRKN-linked familial Parkinson's disease: cellular and molecular mechanisms of disease-linked variants. Cell Mol Life Sci 2024; 81:223. [PMID: 38767677 PMCID: PMC11106057 DOI: 10.1007/s00018-024-05262-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 04/25/2024] [Accepted: 05/02/2024] [Indexed: 05/22/2024]
Abstract
Parkinson's disease (PD) is a common and incurable neurodegenerative disorder that arises from the loss of dopaminergic neurons in the substantia nigra and is mainly characterized by progressive loss of motor function. Monogenic familial PD is associated with highly penetrant variants in specific genes, notably the PRKN gene, where homozygous or compound heterozygous loss-of-function variants predominate. PRKN encodes Parkin, an E3 ubiquitin-protein ligase important for protein ubiquitination and mitophagy of damaged mitochondria. Accordingly, Parkin plays a central role in mitochondrial quality control but is itself also subject to a strict protein quality control system that rapidly eliminates certain disease-linked Parkin variants. Here, we summarize the cellular and molecular functions of Parkin, highlighting the various mechanisms by which PRKN gene variants result in loss-of-function. We emphasize the importance of high-throughput assays and computational tools for the clinical classification of PRKN gene variants and how detailed insights into the pathogenic mechanisms of PRKN gene variants may impact the development of personalized therapeutics.
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Affiliation(s)
- Lene Clausen
- Department of Biology, Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Justyna Okarmus
- Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, 5230, Odense, Denmark
| | - Vasileios Voutsinos
- Department of Biology, Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Morten Meyer
- Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, 5230, Odense, Denmark
- Department of Neurology, Odense University Hospital, 5000, Odense, Denmark
- Department of Clinical Research, BRIDGE, Brain Research Inter Disciplinary Guided Excellence, University of Southern Denmark, 5230, Odense, Denmark
| | - Kresten Lindorff-Larsen
- Department of Biology, Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Rasmus Hartmann-Petersen
- Department of Biology, Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, 2200, Copenhagen, Denmark.
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5
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Zheng C, Nguyen KK, Vishnivetskiy SA, Gurevich VV, Gurevich EV. Arrestin-3 binds parkin and enhances parkin-dependent mitophagy. J Neurochem 2024. [PMID: 38196269 PMCID: PMC11231064 DOI: 10.1111/jnc.16043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 01/11/2024]
Abstract
Arrestins were discovered for their role in homologous desensitization of G-protein-coupled receptors (GPCRs). Later non-visual arrestins were shown to regulate several signaling pathways. Some of these pathways require arrestin binding to GPCRs, the regulation of others is receptor independent. Here, we demonstrate that arrestin-3 binds the E3 ubiquitin ligase parkin via multiple sites, preferentially interacting with its RING0 domain. Identification of the parkin domains involved suggests that arrestin-3 likely relieves parkin autoinhibition and/or stabilizes the enzymatically active "open" conformation of parkin. Arrestin-3 binding enhances ubiquitination by parkin of the mitochondrial protein mitofusin-1 and facilitates parkin-mediated mitophagy in HeLa cells. Furthermore, arrestin-3 and its mutant with enhanced parkin binding rescue mitofusin-1 ubiquitination and mitophagy in the presence of the Parkinson's disease-associated R275W parkin mutant, which is defective in both functions. Thus, modulation of parkin activity via arrestin-3 might be a novel strategy of anti-parkinsonian therapy.
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Affiliation(s)
- Chen Zheng
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
| | - Kevin K Nguyen
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
| | | | - Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
| | - Eugenia V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
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6
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Cheng P, Hou Y, Bian M, Fang X, Liu Y, Rao Y, Cao S, Liu Y, Zhang S, Chen Y, Dong X, Liu Z. Parkin-mediated ubiquitination inhibits BAK apoptotic activity by blocking its canonical hydrophobic groove. Commun Biol 2023; 6:1260. [PMID: 38087033 PMCID: PMC10716173 DOI: 10.1038/s42003-023-05650-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
BAK permeabilizes the mitochondrial outer membrane, causing apoptosis. This apoptotic activity of BAK is stimulated by binding prodeath activators within its canonical hydrophobic groove. Parkin, an E3 ubiquitin (Ub) ligase, can ubiquitinate BAK, which inhibits BAK apoptotic activity. However, the molecular mechanism underlying the inhibition of ubiquitination remains structurally uncharacterized. Here, we utilize truncated and soluble BAK to construct a mimetic of K113-ubiquitinated BAK (disulfide-linked UbG76C ~ BAKK113C) and further present its NMR-derived structure model. The classical L8-I44-H68-V70 hydrophobic patch of the conjugated Ub subunit binds within the canonical hydrophobic groove of BAK. This Ub occludes the binding of prodeath BID activators in the groove and impairs BID-triggered BAK activation and membrane permeabilization. Reduced interaction between Ub and BAK subunits allows BID to activate K113-ubiquitinated BAK. These mechanistic insights suggest a nonsignaling function of Ub in that it directly antagonizes stimuli targeting Ub-modified proteins rather than by recruiting downstream partners for cellular messaging.
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Affiliation(s)
- Peng Cheng
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yuzhu Hou
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Mingxing Bian
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xueru Fang
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yan Liu
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yuanfang Rao
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shuo Cao
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yanjun Liu
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shuai Zhang
- College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yanke Chen
- College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Xu Dong
- Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.
- State Key Laboratory of Biocatalysis and Enzyme Engineering, College of Life Sciences, Hubei University, Wuhan, 430074, China.
| | - Zhu Liu
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, 430070, China.
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7
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Yovanno RA, Yu A, Wied TJ, Lau AY. Phosphorylation at Ser65 modulates ubiquitin conformational dynamics. Structure 2023; 31:884-890.e2. [PMID: 37267945 PMCID: PMC10330661 DOI: 10.1016/j.str.2023.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 03/10/2023] [Accepted: 05/08/2023] [Indexed: 06/04/2023]
Abstract
Ubiquitin phosphorylation at Ser65 increases the population of a rare C-terminally retracted (CR) conformation. Transition between the Major and CR ubiquitin conformations is critical for promoting mitochondrial degradation. The mechanisms by which the Major and CR conformations of Ser65-phosphorylated (pSer65) ubiquitin interconvert, however, remain unresolved. Here, we perform all-atom molecular dynamics simulations using the string method with swarms of trajectories to calculate the lowest free-energy path between these two conformers. Our analysis reveals the existence of a Bent intermediate in which the C-terminal residues of the β5 strand shift to resemble the CR conformation, while pSer65 retains contacts resembling the Major conformation. This stable intermediate was reproduced in well-tempered metadynamics calculations but was less stable for a Gln2Ala mutant that disrupts contacts with pSer65. Lastly, dynamical network modeling reveals that the transition from the Major to CR conformations involves a decoupling of residues near pSer65 from the adjacent β1 strand.
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Affiliation(s)
- Remy A Yovanno
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, WBSB 706, Baltimore, MD 21205, USA
| | - Alvin Yu
- Department of Physiology and Biophysics, University of California, Irvine, 825 Health Sciences Road, Irvine, CA 92697, USA
| | - Tyler J Wied
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, WBSB 706, Baltimore, MD 21205, USA
| | - Albert Y Lau
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, WBSB 706, Baltimore, MD 21205, USA.
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8
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Trempe JF, Gehring K. Structural mechanisms of mitochondrial quality control mediated by PINK1 and parkin. J Mol Biol 2023:168090. [PMID: 37054910 DOI: 10.1016/j.jmb.2023.168090] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/31/2023] [Accepted: 04/05/2023] [Indexed: 04/15/2023]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease and represents a looming public health crisis as the global population ages. While the etiology of the more common, idiopathic form of the disease remains unknown, the last ten years have seen a breakthrough in our understanding of the genetic forms related to two proteins that regulate a quality control system for the removal of damaged or non-functional mitochondria. Here, we review the structure of these proteins, PINK1, a protein kinase, and parkin, a ubiquitin ligase with an emphasis on the molecular mechanisms responsible for their recognition of dysfunctional mitochondria and control of the subsequent ubiquitination cascade. Recent atomic structures have revealed the basis of PINK1 substrate specificity and the conformational changes responsible for activation of PINK1 and parkin catalytic activity. Progress in understanding the molecular basis of mitochondrial quality control promises to open new avenues for therapeutic interventions in PD.
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Affiliation(s)
- Jean-François Trempe
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada; Centre de Recherche en Biologie Structurale
| | - Kalle Gehring
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada; Centre de Recherche en Biologie Structurale
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9
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Connelly EM, Frankel KS, Shaw GS. Parkin and mitochondrial signalling. Cell Signal 2023; 106:110631. [PMID: 36803775 DOI: 10.1016/j.cellsig.2023.110631] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 02/19/2023]
Abstract
Aging, toxic chemicals and changes to the cellular environment are sources of oxidative damage to mitochondria which contribute to neurodegenerative conditions including Parkinson's disease. To counteract this, cells have developed signalling mechanisms to identify and remove select proteins and unhealthy mitochondria to maintain homeostasis. Two important proteins that work in concert to control mitochondrial damage are the protein kinase PINK1 and the E3 ligase parkin. In response to oxidative stress, PINK1 phosphorylates ubiquitin present on proteins at the mitochondrial surface. This signals the translocation of parkin, accelerates further phosphorylation, and stimulates ubiquitination of outer mitochondrial membrane proteins such as Miro1/2 and Mfn1/2. The ubiquitination of these proteins is the key step needed to target them for degradation via the 26S proteasomal machinery or eliminate the entire organelle through mitophagy. This review highlights the signalling mechanisms used by PINK1 and parkin and presents several outstanding questions yet to be resolved.
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Affiliation(s)
- Elizabeth M Connelly
- Department of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Karling S Frankel
- Department of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Gary S Shaw
- Department of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada.
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10
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Wang XS, Cotton TR, Trevelyan SJ, Richardson LW, Lee WT, Silke J, Lechtenberg BC. The unifying catalytic mechanism of the RING-between-RING E3 ubiquitin ligase family. Nat Commun 2023; 14:168. [PMID: 36631489 PMCID: PMC9834252 DOI: 10.1038/s41467-023-35871-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 01/04/2023] [Indexed: 01/12/2023] Open
Abstract
The RING-between-RING (RBR) E3 ubiquitin ligase family in humans comprises 14 members and is defined by a two-step catalytic mechanism in which ubiquitin is first transferred from an E2 ubiquitin-conjugating enzyme to the RBR active site and then to the substrate. To define the core features of this catalytic mechanism, we here structurally and biochemically characterise the two RBRs HOIL-1 and RNF216. Crystal structures of both enzymes in their RBR/E2-Ub/Ub transthiolation complexes capturing the first catalytic step, together with complementary functional experiments, reveal the defining features of the RBR catalytic mechanism. RBRs catalyse ubiquitination via a conserved transthiolation complex structure that enables efficient E2-to-RBR ubiquitin transfer. Our data also highlight a conserved RBR allosteric activation mechanism by distinct ubiquitin linkages that suggests RBRs employ a feed-forward mechanism. We finally identify that the HOIL-1 RING2 domain contains an unusual Zn2/Cys6 binuclear cluster that is required for catalytic activity and substrate ubiquitination.
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Affiliation(s)
- Xiangyi S Wang
- Ubiquitin Signalling Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Thomas R Cotton
- Ubiquitin Signalling Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Sarah J Trevelyan
- Ubiquitin Signalling Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Lachlan W Richardson
- Ubiquitin Signalling Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Wei Ting Lee
- Ubiquitin Signalling Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
| | - John Silke
- Ubiquitin Signalling Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Bernhard C Lechtenberg
- Ubiquitin Signalling Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia. .,Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia.
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11
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Shen X, Sun P, Zhang H, Yang H. Mitochondrial quality control in the brain: The physiological and pathological roles. Front Neurosci 2022; 16:1075141. [PMID: 36578825 PMCID: PMC9791200 DOI: 10.3389/fnins.2022.1075141] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 11/24/2022] [Indexed: 12/14/2022] Open
Abstract
The human brain has high energetic expenses and consumes over 20% of total oxygen metabolism. Abnormal brain energy homeostasis leads to various brain diseases. Among multiple factors that contribute to these diseases, mitochondrial dysfunction is one of the most common causes. Maintenance of mitochondrial integrity and functionality is of pivotal importance to brain energy generation. Mitochondrial quality control (MQC), employing the coordination of multiple mechanisms, is evolved to overcome many mitochondrial defects. Thus, not surprisingly, aberrant mitochondrial quality control results in a wide range of brain disorders. Targeting MQC to preserve and restore mitochondrial function has emerged as a promising therapeutic strategy for the prevention and treatment of brain diseases. Here, we set out to summarize the current understanding of mitochondrial quality control in brain homeostasis. We also evaluate potential pharmaceutically and clinically relevant targets in MQC-associated brain disorders.
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12
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Characterisation of HOIP RBR E3 ligase conformational dynamics using integrative modelling. Sci Rep 2022; 12:15201. [PMID: 36076045 PMCID: PMC9458678 DOI: 10.1038/s41598-022-18890-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 08/22/2022] [Indexed: 11/29/2022] Open
Abstract
Multidomain proteins composed of individual domains connected by flexible linkers pose a challenge for structural studies due to their intrinsic conformational dynamics. Integrated modelling approaches provide a means to characterise protein flexibility by combining experimental measurements with molecular simulations. In this study, we characterise the conformational dynamics of the catalytic RBR domain of the E3 ubiquitin ligase HOIP, which regulates immune and inflammatory signalling pathways. Specifically, we combine small angle X-ray scattering experiments and molecular dynamics simulations to generate weighted conformational ensembles of the HOIP RBR domain using two different approaches based on maximum parsimony and maximum entropy principles. Both methods provide optimised ensembles that are instrumental in rationalising observed differences between SAXS-based solution studies and available crystal structures and highlight the importance of interdomain linker flexibility.
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13
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Fakih R, Sauvé V, Gehring K. Structure of the second phospho-ubiquitin binding site in parkin. J Biol Chem 2022; 298:102114. [PMID: 35690145 PMCID: PMC9284454 DOI: 10.1016/j.jbc.2022.102114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/02/2022] [Accepted: 06/06/2022] [Indexed: 12/28/2022] Open
Abstract
Parkin and PINK1 regulate a mitochondrial quality control system that is mutated in some early onset forms of Parkinson's disease. Parkin is an E3 ubiquitin ligase and regulated by the mitochondrial kinase PINK1 via a two-step cascade. PINK1 first phosphorylates ubiquitin, which binds a recruitment site on parkin to localize parkin to damaged mitochondria. In the second step, PINK1 phosphorylates parkin on its ubiquitin-like domain (Ubl) domain, which binds a regulatory site to release ubiquitin ligase activity. Recently, an alternative feed-forward mechanism was identified that bypasses the need for parkin phosphorylation through the binding of a second phospho-ubiquitin (pUb) molecule. Here, we report the structure of parkin activated through this feed-forward mechanism. The crystal structure of parkin with pUb bound to both the recruitment and regulatory sites reveals the molecular basis for differences in specificity and affinity of the two sites. We use isothermal titration calorimetry measurements to reveal cooperativity between the two binding sites and the role of linker residues for pUbl binding to the regulatory site. The observation of flexibility in the process of parkin activation offers hope for the future design of small molecules for the treatment of Parkinson's disease.
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Affiliation(s)
- Rayan Fakih
- Department of Biochemistry and Centre de recherche en biologie structurale, McGill University, Montreal, Quebec, Canada
| | - Véronique Sauvé
- Department of Biochemistry and Centre de recherche en biologie structurale, McGill University, Montreal, Quebec, Canada
| | - Kalle Gehring
- Department of Biochemistry and Centre de recherche en biologie structurale, McGill University, Montreal, Quebec, Canada.
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14
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Distinct phosphorylation signals drive acceptor versus free ubiquitin chain targeting by Parkin. Biochem J 2022; 479:751-766. [PMID: 35262643 PMCID: PMC9022993 DOI: 10.1042/bcj20210741] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 11/24/2022]
Abstract
The RBR E3 ligase parkin is recruited to the outer mitochondrial membrane (OMM) during oxidative stress where it becomes activated and ubiquitinates numerous proteins. Parkin activation involves binding of a phosphorylated ubiquitin (pUb), followed by phosphorylation of the Ubl domain in parkin, both mediated by the OMM kinase, PINK1. How an OMM protein is selected for ubiquitination is unclear. Parkin targeted OMM proteins have little structural or sequence similarity, with the commonality between substrates being proximity to the OMM. Here, we used chimeric proteins, tagged with ubiquitin (Ub), to evaluate parkin ubiquitination of mitochondrial acceptor proteins pre-ligated to Ub. We find that pUb tethered to the mitochondrial target proteins, Miro1 or CISD1, is necessary for parkin recruitment and essential for target protein ubiquitination. Surprisingly, phosphorylation of parkin is not necessary for the ubiquitination of either Miro1 or CISD1. Thus, parkin lacking its Ubl domain efficiently ubiquitinates a substrate tethered to pUb. Instead, phosphorylated parkin appears to stimulate free Ub chain formation. We also demonstrate that parkin ubiquitination of pUb-tethered substrates occurs on the substrate, rather than the pUb modification. We propose divergent parkin mechanisms whereby parkin-mediated ubiquitination of acceptor proteins is driven by binding to pre-existing pUb on the OMM protein and subsequent parkin phosphorylation triggers free Ub chain formation. This finding accounts for the broad spectrum of OMM proteins ubiquitinated by parkin and has implications on target design for therapeutics.
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15
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Birkou M, Raptis V, Marousis KD, Tsevis A, Bourikas K, Bentrop D, Episkopou V, Spyroulias GA. Impact of a Single Nucleotide Polymorphism on the 3D Protein Structure and Ubiquitination Activity of E3 Ubiquitin Ligase Arkadia. Front Mol Biosci 2022; 9:844129. [PMID: 35281275 PMCID: PMC8905620 DOI: 10.3389/fmolb.2022.844129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 01/31/2022] [Indexed: 11/16/2022] Open
Abstract
Single nucleotide polymorphisms (SNPs) are genetic variations which can play a vital role in the study of human health. SNP studies are often used to identify point mutations that are associated with diseases. Arkadia (RNF111) is an E3 ubiquitin ligase that enhances transforming growth factor-beta (TGF-β) signaling by targeting negative regulators for degradation. Dysregulation of the TGF-β pathway is implicated in cancer because it exhibits tumor suppressive activity in normal cells while in tumor cells it promotes invasiveness and metastasis. Τhe SNP CGT > TGT generated an amino-acid (aa) substitution of Arginine 957 to Cysteine on the enzymatic RING domain of Arkadia. This was more prevalent in a tumor than in a normal tissue sample of a patient with colorectal cancer. This prompted us to investigate the effect of this mutation in the structure and activity of Arkadia RING. We used nuclear magnetic resonance (NMR) to analyze at an atomic-level the structural and dynamic properties of the R957C Arkadia RING domain, while ubiquitination and luciferase assays provided information about its enzymatic functionality. Our study showed that the R957C mutation changed the electrostatic properties of the RING domain however, without significant effects on the structure of its core region. However, the functional studies revealed that the R957C Arkadia exhibits significantly increased enzymatic activity supporting literature data that Arkadia within tumor cells promotes aggressive and metastatic behavior.
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Affiliation(s)
- Maria Birkou
- Department of Pharmacy, University of Patras, Patras, Greece
| | - Vasilios Raptis
- Department of Pharmacy, University of Patras, Patras, Greece
| | | | - Athanasios Tsevis
- School of Science and Technology, Hellenic Open University, Patras, Greece
| | - Kyriakos Bourikas
- School of Science and Technology, Hellenic Open University, Patras, Greece
| | - Detlef Bentrop
- Institute of Physiology II, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Vasso Episkopou
- Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, Burlington Danes, London, United Kingdom
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16
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A Novel Method for Identifying Parkin Binding Agents in Complex Preparations of Herbal Medicines. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:3260243. [PMID: 35087614 PMCID: PMC8789414 DOI: 10.1155/2022/3260243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 11/11/2021] [Accepted: 12/04/2021] [Indexed: 11/24/2022]
Abstract
Parkin is a crucial E3 ubiquitin ligase for initiating mitophagy through the PINK1/Parkin pathway. Regulating the expression and activity of parkin can remedy mitophagy and human disease. We developed an efficient method to isolate natural parkin ligands from herbal medicines by combining centrifugal ultrafiltration and liquid chromatography/mass spectrometry. The heterologous expression technology identified functionally active and pure parkin proteins. After evaluating the reliability of the method using DL-selenomethionine and DL-dithiothreitol as positive controls, this method was successfully applied to capture parkin ligands from Polygoni Cuspidati Rhizoma et Radix and Sophorae Flavescentis Radix. LC/MS identified seven novel parkin-targeting compounds, namely, 7,4′-dihydroxy-5-methoxy-8-(γ, γ-dimethylallyl)-flavanone, kushenol I, kurarinone, sophoraflavanone G, torachrysone-8-O-glucoside, apigenin, and emodin, supported by the molecular docking analysis. Five of the seven novel compounds (kushenol I, kurarinone, sophoraflavanone G, apigenin, and emodin) can activate parkin in in vitro autoubiquitination assays. Meanwhile, kushenol I and kurarinone had antisteatosis activity in fat emulsion-damaged human hepatocytes. These results confirmed the effectiveness of the method for identifying parkin ligands from complex preparations, useful to advance drug discovery from medicinal herbs.
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17
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Abstract
Mutations in the protein kinase PINK1 lead to defects in mitophagy and cause autosomal recessive early onset Parkinson's disease1,2. PINK1 has many unique features that enable it to phosphorylate ubiquitin and the ubiquitin-like domain of Parkin3-9. Structural analysis of PINK1 from diverse insect species10-12 with and without ubiquitin provided snapshots of distinct structural states yet did not explain how PINK1 is activated. Here we elucidate the activation mechanism of PINK1 using crystallography and cryo-electron microscopy (cryo-EM). A crystal structure of unphosphorylated Pediculus humanus corporis (Ph; human body louse) PINK1 resolves an N-terminal helix, revealing the orientation of unphosphorylated yet active PINK1 on the mitochondria. We further provide a cryo-EM structure of a symmetric PhPINK1 dimer trapped during the process of trans-autophosphorylation, as well as a cryo-EM structure of phosphorylated PhPINK1 undergoing a conformational change to an active ubiquitin kinase state. Structures and phosphorylation studies further identify a role for regulatory PINK1 oxidation. Together, our research delineates the complete activation mechanism of PINK1, illuminates how PINK1 interacts with the mitochondrial outer membrane and reveals how PINK1 activity may be modulated by mitochondrial reactive oxygen species.
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18
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Liu JY, Inoshita T, Shiba-Fukushima K, Yoshida S, Ogata K, Ishihama Y, Imai Y, Hattori N. OUP accepted manuscript. Hum Mol Genet 2022; 31:2623-2638. [PMID: 35313349 PMCID: PMC9396936 DOI: 10.1093/hmg/ddac064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 01/11/2022] [Accepted: 03/14/2022] [Indexed: 11/13/2022] Open
Abstract
The mitochondrial kinase PTEN-induced kinase 1 (PINK1) and cytosolic ubiquitin ligase (E3) Parkin/PRKN are involved in mitochondrial quality control responses. PINK1 phosphorylates ubiquitin and the Parkin ubiquitin-like (Ubl) domain at serine 65 and promotes Parkin activation and translocation to damaged mitochondria. Upon Parkin activation, the Ubl domain is ubiquitinated at lysine (K) 27 and K48 residues. However, the contribution of K27/K48 ubiquitination toward Parkin activity remains unclear. In this study, ubiquitination of K56 (corresponding to K27 in the human), K77 (K48 in the human) or both was blocked by generating Drosophila Parkin (dParkin) mutants to examine the effects of Parkin Ubl domain ubiquitination on Parkin activation in Drosophila. The dParkin, in which K56 was replaced with arginine (dParkin K56R), rescued pupal lethality in flies by co-expression with PINK1, whereas dParkin K77R could not. The dParkin K56R exhibited reduced abilities of mitochondrial fragmentation and motility arrest, which are mediated by degrading Parkin E3 substrates Mitofusin and Miro, respectively. Pathogenic dParkin K56N, unlike dParkin K56R, destabilized the protein, suggesting that not only was dParkin K56N non-ubiquitin-modified at K56, but also the structure of the Ubl domain for activation was largely affected. Ubiquitin attached to K27 of the Ubl domain during PINK1-mediated Parkin activation was likely to be phosphorylated because human Parkin K27R weakened Parkin self-binding and activation in trans. Therefore, our findings suggest a new mechanism of Parkin activation, where an activation complex is formed through phospho-ubiquitin attachment on the K27 residue of the Parkin Ubl domain.
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Affiliation(s)
- Jun-Yi Liu
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Tsuyoshi Inoshita
- Department of Neurodegenerative and Demented Disorders, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Kahori Shiba-Fukushima
- Department of Drug Development for Parkinson’s Disease, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Shigeharu Yoshida
- Department of Molecular and Cellular BioAnalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Kosuke Ogata
- Department of Molecular and Cellular BioAnalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Yasushi Ishihama
- Department of Molecular and Cellular BioAnalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Yuzuru Imai
- To whom correspondence should be addressed at: Yuzuru Imai, Research for Parkinson's Disease, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan. Tel: +81 368018332; Fax: +81-3-5800-0547; ; Nobutaka Hattori, Department of Neurology, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan, Tel: +81 358022731; Fax: +81-3-5800-0547;
| | - Nobutaka Hattori
- To whom correspondence should be addressed at: Yuzuru Imai, Research for Parkinson's Disease, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan. Tel: +81 368018332; Fax: +81-3-5800-0547; ; Nobutaka Hattori, Department of Neurology, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan, Tel: +81 358022731; Fax: +81-3-5800-0547;
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19
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PINK1 signalling in neurodegenerative disease. Essays Biochem 2021; 65:913-923. [PMID: 34897410 PMCID: PMC8709887 DOI: 10.1042/ebc20210036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 11/03/2021] [Accepted: 11/16/2021] [Indexed: 12/26/2022]
Abstract
PTEN-induced kinase 1 (PINK1) impacts cell health and human pathology through diverse pathways. The strict processing of full-length PINK1 on the outer mitochondrial membrane populates a cytoplasmic pool of cleaved PINK1 (cPINK1) that is constitutively degraded. However, despite rapid proteasomal clearance, cPINK1 still appears to exert quality control influence over the neuronal protein homeostasis network, including protein synthesis and degradation machineries. The cytoplasmic concentration and activity of this molecule is therefore a powerful sensor that coordinates aspects of mitochondrial and cellular health. In addition, full-length PINK1 is retained on the mitochondrial membrane following depolarisation, where it is a powerful inducer of multiple mitophagic pathways. This function is executed primarily through the phosphorylation of several ubiquitin ligases, including its most widely studied substrate Parkin. Furthermore, the phosphorylation of both pro- and anti-apoptotic proteins by mitochondrial PINK1 acts as a pro-cellular survival signal when faced with apoptotic stimuli. Through these varied roles PINK1 directly influences functions central to cell dysfunction in neurodegenerative disease.
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20
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Henneberg LT, Schulman BA. Decoding the messaging of the ubiquitin system using chemical and protein probes. Cell Chem Biol 2021; 28:889-902. [PMID: 33831368 PMCID: PMC7611516 DOI: 10.1016/j.chembiol.2021.03.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/22/2021] [Accepted: 03/12/2021] [Indexed: 12/29/2022]
Abstract
Post-translational modification of proteins by ubiquitin is required for nearly all aspects of eukaryotic cell function. The numerous targets of ubiquitylation, and variety of ubiquitin modifications, are often likened to a code, where the ultimate messages are diverse responses to target ubiquitylation. E1, E2, and E3 multiprotein enzymatic assemblies modify specific targets and thus function as messengers. Recent advances in chemical and protein tools have revolutionized our ability to explore the ubiquitin system, through enabling new high-throughput screening methods, matching ubiquitylation enzymes with their cellular targets, revealing intricate allosteric mechanisms regulating ubiquitylating enzymes, facilitating structural revelation of transient assemblies determined by multivalent interactions, and providing new paradigms for inhibiting and redirecting ubiquitylation in vivo as new therapeutics. Here we discuss the development of methods that control, disrupt, and extract the flow of information across the ubiquitin system and have enabled elucidation of the underlying molecular and cellular biology.
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Affiliation(s)
- Lukas T Henneberg
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Brenda A Schulman
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany.
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21
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Chain reactions: molecular mechanisms of RBR ubiquitin ligases. Biochem Soc Trans 2021; 48:1737-1750. [PMID: 32677670 PMCID: PMC7458406 DOI: 10.1042/bst20200237] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/23/2020] [Accepted: 06/24/2020] [Indexed: 12/13/2022]
Abstract
Ubiquitination is a fundamental post-translational modification that regulates almost all aspects of cellular signalling and is ultimately catalysed by the action of E3 ubiquitin ligases. The RING-between-RING (RBR) family of E3 ligases encompasses 14 distinct human enzymes that are defined by a unique domain organisation and catalytic mechanism. Detailed characterisation of several RBR ligase family members in the last decade has revealed common structural and mechanistic features. At the same time these studies have highlighted critical differences with respect to autoinhibition, activation and catalysis. Importantly, the majority of RBR E3 ligases remain poorly studied, and thus the extent of diversity within the family remains unknown. In this mini-review we outline the current understanding of the RBR E3 mechanism, structure and regulation with a particular focus on recent findings and developments that will shape the field in coming years.
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22
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Gundogdu M, Tadayon R, Salzano G, Shaw GS, Walden H. A mechanistic review of Parkin activation. Biochim Biophys Acta Gen Subj 2021; 1865:129894. [PMID: 33753174 DOI: 10.1016/j.bbagen.2021.129894] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 03/05/2021] [Accepted: 03/18/2021] [Indexed: 11/17/2022]
Abstract
Parkin and phosphatase and tensin homolog (PTEN)-induced kinase 1 (PINK1) constitute a feed-forward signalling pathway that mediates autophagic removal of damaged mitochondria (mitophagy). With over 130 mutations identified to date in over 1000 patients with early onset parkinsonism, Parkin is considered a hot spot of signalling pathways involved in PD aetiology. Parkin is an E3 ligase and how its activity is regulated has been extensively studied: inter-domain interactions exert a tight inhibition on Parkin activity; binding to phospho-ubiquitin relieves this auto-inhibition; and phosphorylation of Parkin shifts the equilibrium towards maximal Parkin activation. This review focusses on recent, structural findings on the regulation of Parkin activity. What follows is a mechanistic introduction to the family of E3 ligases that includes Parkin, followed by a brief description of structural elements unique to Parkin that lock the enzyme in an autoinhibited state, contrasted with emerging models that have shed light on possible mechanisms of Parkin activation.
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Affiliation(s)
- Mehmet Gundogdu
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Roya Tadayon
- Department of Biochemistry, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Giulia Salzano
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Gary S Shaw
- Department of Biochemistry, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Helen Walden
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.
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23
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Horn-Ghetko D, Krist DT, Prabu JR, Baek K, Mulder MPC, Klügel M, Scott DC, Ovaa H, Kleiger G, Schulman BA. Ubiquitin ligation to F-box protein targets by SCF-RBR E3-E3 super-assembly. Nature 2021; 590:671-676. [PMID: 33536622 PMCID: PMC7904520 DOI: 10.1038/s41586-021-03197-9] [Citation(s) in RCA: 94] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 12/18/2020] [Indexed: 01/30/2023]
Abstract
E3 ligases are typically classified by hallmark domains such as RING and RBR, which are thought to specify unique catalytic mechanisms of ubiquitin transfer to recruited substrates1,2. However, rather than functioning individually, many neddylated cullin-RING E3 ligases (CRLs) and RBR-type E3 ligases in the ARIH family-which together account for nearly half of all ubiquitin ligases in humans-form E3-E3 super-assemblies3-7. Here, by studying CRLs in the SKP1-CUL1-F-box (SCF) family, we show how neddylated SCF ligases and ARIH1 (an RBR-type E3 ligase) co-evolved to ubiquitylate diverse substrates presented on various F-box proteins. We developed activity-based chemical probes that enabled cryo-electron microscopy visualization of steps in E3-E3 ubiquitylation, initiating with ubiquitin linked to the E2 enzyme UBE2L3, then transferred to the catalytic cysteine of ARIH1, and culminating in ubiquitin linkage to a substrate bound to the SCF E3 ligase. The E3-E3 mechanism places the ubiquitin-linked active site of ARIH1 adjacent to substrates bound to F-box proteins (for example, substrates with folded structures or limited length) that are incompatible with previously described conventional RING E3-only mechanisms. The versatile E3-E3 super-assembly may therefore underlie widespread ubiquitylation.
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Affiliation(s)
- Daniel Horn-Ghetko
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - David T Krist
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
- Carle Illinois College of Medicine, Champaign, IL, USA
| | - J Rajan Prabu
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Kheewoong Baek
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Monique P C Mulder
- Oncode Institute, Department of Cell and Chemical Biology, Chemical Immunology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Maren Klügel
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Daniel C Scott
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Huib Ovaa
- Oncode Institute, Department of Cell and Chemical Biology, Chemical Immunology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Gary Kleiger
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, Las Vegas, NV, USA
| | - Brenda A Schulman
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany.
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA.
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24
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Kostrhon S, Prabu JR, Baek K, Horn-Ghetko D, von Gronau S, Klügel M, Basquin J, Alpi AF, Schulman BA. CUL5-ARIH2 E3-E3 ubiquitin ligase structure reveals cullin-specific NEDD8 activation. Nat Chem Biol 2021; 17:1075-1083. [PMID: 34518685 PMCID: PMC8460447 DOI: 10.1038/s41589-021-00858-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Accepted: 07/06/2021] [Indexed: 02/08/2023]
Abstract
An emerging mechanism of ubiquitylation involves partnering of two distinct E3 ligases. In the best-characterized E3-E3 pathways, ARIH-family RING-between-RING (RBR) E3s ligate ubiquitin to substrates of neddylated cullin-RING E3s. The E3 ARIH2 has been implicated in ubiquitylation of substrates of neddylated CUL5-RBX2-based E3s, including APOBEC3-family substrates of the host E3 hijacked by HIV-1 virion infectivity factor (Vif). However, the structural mechanisms remained elusive. Here structural and biochemical analyses reveal distinctive ARIH2 autoinhibition, and activation on assembly with neddylated CUL5-RBX2. Comparison to structures of E3-E3 assemblies comprising ARIH1 and neddylated CUL1-RBX1-based E3s shows cullin-specific regulation by NEDD8. Whereas CUL1-linked NEDD8 directly recruits ARIH1, CUL5-linked NEDD8 does not bind ARIH2. Instead, the data reveal an allosteric mechanism. NEDD8 uniquely contacts covalently linked CUL5, and elicits structural rearrangements that unveil cryptic ARIH2-binding sites. The data reveal how a ubiquitin-like protein induces protein-protein interactions indirectly, through allostery. Allosteric specificity of ubiquitin-like protein modifications may offer opportunities for therapeutic targeting.
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Affiliation(s)
- Sebastian Kostrhon
- grid.418615.f0000 0004 0491 845XDepartment of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - J. Rajan Prabu
- grid.418615.f0000 0004 0491 845XDepartment of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Kheewoong Baek
- grid.418615.f0000 0004 0491 845XDepartment of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Daniel Horn-Ghetko
- grid.418615.f0000 0004 0491 845XDepartment of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Susanne von Gronau
- grid.418615.f0000 0004 0491 845XDepartment of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Maren Klügel
- grid.418615.f0000 0004 0491 845XDepartment of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jérôme Basquin
- grid.418615.f0000 0004 0491 845XDepartment of Structural Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Arno F. Alpi
- grid.418615.f0000 0004 0491 845XDepartment of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Brenda A. Schulman
- grid.418615.f0000 0004 0491 845XDepartment of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
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25
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Srivastava SP, Kanasaki K, Goodwin JE. Loss of Mitochondrial Control Impacts Renal Health. Front Pharmacol 2020; 11:543973. [PMID: 33362536 PMCID: PMC7756079 DOI: 10.3389/fphar.2020.543973] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 11/19/2020] [Indexed: 12/13/2022] Open
Abstract
Disruption of mitochondrial biosynthesis or dynamics, or loss of control over mitochondrial regulation leads to a significant alteration in fuel preference and metabolic shifts that potentially affect the health of kidney cells. Mitochondria regulate metabolic networks which affect multiple cellular processes. Indeed, mitochondria have established themselves as therapeutic targets in several diseases. The importance of mitochondria in regulating the pathogenesis of several diseases has been recognized, however, there is limited understanding of mitochondrial biology in the kidney. This review provides an overview of mitochondrial dysfunction in kidney diseases. We describe the importance of mitochondria and mitochondrial sirtuins in the regulation of renal metabolic shifts in diverse cells types, and review this loss of control leads to increased cell-to-cell transdifferentiation processes and myofibroblast-metabolic shifts, which affect the pathophysiology of several kidney diseases. In addition, we examine mitochondrial-targeted therapeutic agents that offer potential leads in combating kidney diseases.
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Affiliation(s)
- Swayam Prakash Srivastava
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT, United States
- Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT, United States
| | - Keizo Kanasaki
- Internal Medicine 1, Shimane University Faculty of Medicine, Izumo, Japan
| | - Julie E. Goodwin
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT, United States
- Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT, United States
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26
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Quinn PMJ, Moreira PI, Ambrósio AF, Alves CH. PINK1/PARKIN signalling in neurodegeneration and neuroinflammation. Acta Neuropathol Commun 2020; 8:189. [PMID: 33168089 PMCID: PMC7654589 DOI: 10.1186/s40478-020-01062-w] [Citation(s) in RCA: 212] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 10/17/2020] [Indexed: 12/13/2022] Open
Abstract
Mutations in the PTEN-induced kinase 1 (PINK1) and Parkin RBR E3 ubiquitin-protein ligase (PARKIN) genes are associated with familial forms of Parkinson’s disease (PD). PINK1, a protein kinase, and PARKIN, an E3 ubiquitin ligase, control the specific elimination of dysfunctional or superfluous mitochondria, thus fine-tuning mitochondrial network and preserving energy metabolism. PINK1 regulates PARKIN translocation in impaired mitochondria and drives their removal via selective autophagy, a process known as mitophagy. As knowledge obtained using different PINK1 and PARKIN transgenic animal models is being gathered, growing evidence supports the contribution of mitophagy impairment to several human pathologies, including PD and Alzheimer’s diseases (AD). Therefore, therapeutic interventions aiming to modulate PINK1/PARKIN signalling might have the potential to treat these diseases. In this review, we will start by discussing how the interplay of PINK1 and PARKIN signalling helps mediate mitochondrial physiology. We will continue by debating the role of mitochondrial dysfunction in disorders such as amyotrophic lateral sclerosis, Alzheimer’s, Huntington’s and Parkinson’s diseases, as well as eye diseases such as age-related macular degeneration and glaucoma, and the causative factors leading to PINK1/PARKIN-mediated neurodegeneration and neuroinflammation. Finally, we will discuss PINK1/PARKIN gene augmentation possibilities with a particular focus on AD, PD and glaucoma.
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Joaquim M, Escobar-Henriques M. Role of Mitofusins and Mitophagy in Life or Death Decisions. Front Cell Dev Biol 2020; 8:572182. [PMID: 33072754 PMCID: PMC7539839 DOI: 10.3389/fcell.2020.572182] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 09/03/2020] [Indexed: 12/12/2022] Open
Abstract
Mitochondria entail an incredible dynamism in their morphology, impacting death signaling and selective elimination of the damaged organelles. In turn, by recycling the superfluous or malfunctioning mitochondria, mostly prevalent during aging, mitophagy contributes to maintain a healthy mitochondrial network. Mitofusins locate at the outer mitochondrial membrane and control the plastic behavior of mitochondria, by mediating fusion events. Besides deciding on mitochondrial interconnectivity, mitofusin 2 regulates physical contacts between mitochondria and the endoplasmic reticulum, but also serves as a decisive docking platform for mitophagy and apoptosis effectors. Thus, mitofusins integrate multiple bidirectional inputs from and into mitochondria and ensure proper energetic and metabolic cellular performance. Here, we review the role of mitofusins and mitophagy at the cross-road between life and apoptotic death decisions. Furthermore, we highlight the impact of this interplay on disease, focusing on how mitofusin 2 and mitophagy affect non-alcoholic fatty liver disease.
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Affiliation(s)
- Mariana Joaquim
- Institute for Genetics, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Mafalda Escobar-Henriques
- Institute for Genetics, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
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28
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Rennie ML, Chaugule VK, Walden H. Modes of allosteric regulation of the ubiquitination machinery. Curr Opin Struct Biol 2020; 62:189-196. [PMID: 32305021 DOI: 10.1016/j.sbi.2020.02.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 01/29/2020] [Accepted: 02/25/2020] [Indexed: 02/06/2023]
Abstract
Ubiquitination is a post-translational modification crucial for cellular signaling. A diverse range of enzymes constitute the machinery that mediates attachment of ubiquitin onto target proteins. This diversity allows the targeting of various proteins in a highly regulated fashion. Many of the enzymes have multiple domains or subunits that bind allosteric effectors and exhibit large conformational rearrangements to facilitate regulation. Here we consider recent examples of ubiquitin itself as an allosteric effector of RING and RBR E3 ligases, as well as advances in the understanding of allosteric regulatory elements within HECT E3 ligases.
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Affiliation(s)
- Martin L Rennie
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Viduth K Chaugule
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Helen Walden
- Institute of Molecular Cell and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.
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29
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Luo Y, Jiang C, Yu L, Yang A. Chemical Biology of Autophagy-Related Proteins With Posttranslational Modifications: From Chemical Synthesis to Biological Applications. Front Chem 2020; 8:233. [PMID: 32309274 PMCID: PMC7145982 DOI: 10.3389/fchem.2020.00233] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 03/11/2020] [Indexed: 02/03/2023] Open
Abstract
Macroautophagy (hereafter referred to as autophagy) is an evolutionarily conserved lysosomal degradation pathway in all eukaryotic cells, which is critical for maintaining cell homeostasis. A series of autophagy-related (ATG) proteins are involved in the regulation of autophagy. The activities of ATG proteins are mainly modulated by posttranslational modifications (PTMs), such as phosphorylation, lipidation, acetylation, ubiquitination, and sumoylation. To tackle molecular mechanisms of autophagy, more and more researches are focusing on the roles of PTMs in regulation of the activity of ATG proteins and autophagy process. The protein ligation techniques have emerged as powerful tools for the chemical engineering of proteins with PTMs, and provided effective methods to elucidate the molecular mechanism and physiological significance of PTMs. Recently, several ATG proteins with PTM were prepared by protein ligation techniques such as native chemical ligation (NCL), expressed protein ligation (EPL), peptide hydrazide-based NCL, and Sortase A-mediated ligation (SML). More importantly, the synthesized ATG proteins are successfully used to probe the mechanism of autophagy. In this review, we summarize protein ligation techniques for the preparation of ATG proteins with PTMs. In addition, we highlight the biological applications of synthetic ATG proteins to probe the autophagy mechanism.
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Affiliation(s)
- Yu Luo
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Chen Jiang
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Lihua Yu
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Aimin Yang
- School of Life Sciences, Chongqing University, Chongqing, China
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30
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Matsuda N, Yamano K. Two sides of a coin: Physiological significance and molecular mechanisms for damage-induced mitochondrial localization of PINK1 and Parkin. Neurosci Res 2020; 159:16-24. [PMID: 32201358 DOI: 10.1016/j.neures.2020.03.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/06/2020] [Accepted: 03/10/2020] [Indexed: 12/26/2022]
Abstract
In 1998, PARKIN was reported as a causal gene for hereditary recessive Parkinsonism by Kitada, Mizuno, Hattori, and Shimizu et al. Later in 2004, PINK1 was also reported as a causal gene for hereditary recessive Parkinsonism by Valente, Auburger, and Wood et al. Although many unsolved mysteries still remain, our knowledge of PINK1 and Parkin function has increased dramatically since then. Despite a number of milestone studies that advanced the PINK1 and Parkin research field, a critical turning point was undoubtedly the determination that their genuine subcellular localization was on depolarized mitochondria. In this review, we outline the key studies that have contributed to our current model for mitochondrial localization of PINK1 and Parkin. Interestingly, like two sides of a coin, our attempts to elucidate the mechanisms underlying the localization of PINK1 and Parkin were inextricably tied to the identification of the PINK1 substrate and molecular dissection of the Parkin activation mechanism.
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Affiliation(s)
- Noriyuki Matsuda
- The Ubiquitin Project, Tokyo Metropolitan Institute of Medical Science, Room N-202, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan.
| | - Koji Yamano
- The Ubiquitin Project, Tokyo Metropolitan Institute of Medical Science, Room N-202, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan
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31
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Yi W, MacDougall EJ, Tang MY, Krahn AI, Gan-Or Z, Trempe JF, Fon EA. The landscape of Parkin variants reveals pathogenic mechanisms and therapeutic targets in Parkinson's disease. Hum Mol Genet 2020; 28:2811-2825. [PMID: 30994895 DOI: 10.1093/hmg/ddz080] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/02/2019] [Accepted: 04/15/2019] [Indexed: 11/14/2022] Open
Abstract
Mutations in Parkin (PARK2), which encodes an E3 ubiquitin ligase implicated in mitophagy, are the most common cause of early-onset Parkinson's disease (EOPD). Hundreds of naturally occurring Parkin variants have been reported, both in Parkinson's disease (PD) patient and population databases. However, the effects of the majority of these variants on the function of Parkin and in PD pathogenesis remain unknown. Here we develop a framework for classification of the pathogenicity of Parkin variants based on the integration of clinical and functional evidence-including measures of mitophagy and protein stability and predictive structural modeling-and assess 51 naturally occurring Parkin variants accordingly. Surprisingly, only a minority of Parkin variants, even among those previously associated with PD, disrupted Parkin function. Moreover, a few of these naturally occurring Parkin variants actually enhanced mitophagy. Interestingly, impaired mitophagy in several of the most common pathogenic Parkin variants could be rescued both by naturally occurring (p.V224A) and structure-guided designer (p.W403A; p.F146A) hyperactive Parkin variants. Together, the findings provide a coherent framework to classify Parkin variants based on pathogenicity and suggest that several pathogenic Parkin variants represent promising targets to stratify patients for genotype-specific drug design.
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Affiliation(s)
- Wei Yi
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Emma J MacDougall
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Matthew Y Tang
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Andrea I Krahn
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Ziv Gan-Or
- Montreal Neurological Institute and Hospital, Department of Neurology and Neurosurgery, Department of Human Genetics, McGill University, Montreal, QC, Canada
| | - Jean-François Trempe
- Groupe de Recherche Axé sur la Structure des Protéines, Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Edward A Fon
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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Tsai YCI, Johansson H, Dixon D, Martin S, Chung CW, Clarkson J, House D, Rittinger K. Single-Domain Antibodies as Crystallization Chaperones to Enable Structure-Based Inhibitor Development for RBR E3 Ubiquitin Ligases. Cell Chem Biol 2020; 27:83-93.e9. [PMID: 31813847 PMCID: PMC6963773 DOI: 10.1016/j.chembiol.2019.11.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/15/2019] [Accepted: 11/14/2019] [Indexed: 01/14/2023]
Abstract
Protein ubiquitination plays a key role in the regulation of cellular processes, and misregulation of the ubiquitin system is linked to many diseases. So far, development of tool compounds that target enzymes of the ubiquitin system has been slow and only a few specific inhibitors are available. Here, we report the selection of single-domain antibodies (single-dAbs) based on a human scaffold that recognize the catalytic domain of HOIP, a subunit of the multi-component E3 LUBAC and member of the RBR family of E3 ligases. Some of these dAbs affect ligase activity and provide mechanistic insight into the ubiquitin transfer mechanism of different E2-conjugating enzymes. Furthermore, we show that the co-crystal structure of a HOIP RBR/dAb complex serves as a robust platform for soaking of ligands that target the active site cysteine of HOIP, thereby providing easy access to structure-based ligand design for this important class of E3 ligases.
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Affiliation(s)
- Yi-Chun Isabella Tsai
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Henrik Johansson
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Crick-GSK Biomedical LinkLabs, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - David Dixon
- R&D Medicinal Science & Technology, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - Stephen Martin
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Chun-Wa Chung
- Crick-GSK Biomedical LinkLabs, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; R&D Medicinal Science & Technology, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - Jane Clarkson
- R&D Medicinal Science & Technology, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - David House
- Crick-GSK Biomedical LinkLabs, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - Katrin Rittinger
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
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Di Rita A, Maiorino T, Bruqi K, Volpicelli F, Bellenchi GC, Strappazzon F. miR-218 Inhibits Mitochondrial Clearance by Targeting PRKN E3 Ubiquitin Ligase. Int J Mol Sci 2020; 21:ijms21010355. [PMID: 31948106 PMCID: PMC6981953 DOI: 10.3390/ijms21010355] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 12/28/2019] [Accepted: 01/03/2020] [Indexed: 01/10/2023] Open
Abstract
The selective elimination of dysfunctional mitochondria through mitophagy is crucial for preserving mitochondrial quality and cellular homeostasis. The most described mitophagy pathway is regulated by a positive ubiquitylation feedback loop in which the PINK1 (PTEN induced kinase 1) kinase phosphorylates both ubiquitin and the E3 ubiquitin ligase PRKN (Parkin RBR E3 ubiquitin ligase), also known as PARKIN. This event recruits PRKN to the mitochondria, thus amplifying ubiquitylation signal. Here we report that miR-218 targets PRKN and negatively regulates PINK1/PRKN-mediated mitophagy. Overexpression of miR-218 reduces PRKN mRNA levels, thus also reducing protein content and deregulating the E3 ubiquitin ligase action. In fact, following miR-218 overexpression, mitochondria result less ubiquitylated and the autophagy machinery fails to proceed with correct mitochondrial clearance. Since mitophagy defects are associated with various human diseases, these results qualify miR-218 as a promising therapeutic target for human diseases.
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Affiliation(s)
- Anthea Di Rita
- IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (A.D.R.); (T.M.); (K.B.); (G.C.B.)
- University of Rome Tor Vergata, 00133 Rome, Italy
| | - Teresa Maiorino
- IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (A.D.R.); (T.M.); (K.B.); (G.C.B.)
| | - Krenare Bruqi
- IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (A.D.R.); (T.M.); (K.B.); (G.C.B.)
- University of Rome Tor Vergata, 00133 Rome, Italy
| | - Floriana Volpicelli
- Institute of Genetics and Biophysics “Adriano Buzzati Traverso”, CNR, 80131 Naples, Italy;
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy
| | - Gian Carlo Bellenchi
- IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (A.D.R.); (T.M.); (K.B.); (G.C.B.)
- Institute of Genetics and Biophysics “Adriano Buzzati Traverso”, CNR, 80131 Naples, Italy;
- Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Flavie Strappazzon
- IRCCS Fondazione Santa Lucia, 00143 Rome, Italy; (A.D.R.); (T.M.); (K.B.); (G.C.B.)
- Correspondence: ; Tel.: +39-06501703093
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34
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Wang L, Qi H, Tang Y, Shen HM. Post-translational Modifications of Key Machinery in the Control of Mitophagy. Trends Biochem Sci 2020; 45:58-75. [DOI: 10.1016/j.tibs.2019.08.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/05/2019] [Accepted: 08/16/2019] [Indexed: 12/12/2022]
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Bayne AN, Trempe JF. Mechanisms of PINK1, ubiquitin and Parkin interactions in mitochondrial quality control and beyond. Cell Mol Life Sci 2019; 76:4589-4611. [PMID: 31254044 PMCID: PMC11105328 DOI: 10.1007/s00018-019-03203-4] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 06/13/2019] [Accepted: 06/19/2019] [Indexed: 12/20/2022]
Abstract
Parkinson's disease (PD) is a degenerative movement disorder resulting from the loss of specific neuron types in the midbrain. Early environmental and pathophysiological studies implicated mitochondrial damage and protein aggregation as the main causes of PD. These findings are now vindicated by the characterization of more than 20 genes implicated in rare familial forms of the disease. In particular, two proteins encoded by the Parkin and PINK1 genes, whose mutations cause early-onset autosomal recessive PD, function together in a mitochondrial quality control pathway. In this review, we will describe recent development in our understanding of their mechanisms of action, structure, and function. We explain how PINK1 acts as a mitochondrial damage sensor via the regulated proteolysis of its N-terminus and the phosphorylation of ubiquitin tethered to outer mitochondrial membrane proteins. In turn, phospho-ubiquitin recruits and activates Parkin via conformational changes that increase its ubiquitin ligase activity. We then describe how the formation of polyubiquitin chains on mitochondria triggers the recruitment of the autophagy machinery or the formation of mitochondria-derived vesicles. Finally, we discuss the evidence for the involvement of these mechanisms in physiological processes such as immunity and inflammation, as well as the links to other PD genes.
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Affiliation(s)
- Andrew N Bayne
- Department of Pharmacology and Therapeutics and Centre for Structural Biology, McGill University, 3655 Prom Sir William Osler, Montreal, QC, H3G 1Y6, Canada
| | - Jean-François Trempe
- Department of Pharmacology and Therapeutics and Centre for Structural Biology, McGill University, 3655 Prom Sir William Osler, Montreal, QC, H3G 1Y6, Canada.
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Kovalchuke L, Mosharov EV, Levy OA, Greene LA. Stress-induced phospho-ubiquitin formation causes parkin degradation. Sci Rep 2019; 9:11682. [PMID: 31406131 PMCID: PMC6690910 DOI: 10.1038/s41598-019-47952-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 07/26/2019] [Indexed: 12/21/2022] Open
Abstract
Mutations in the E3 ubiquitin ligase parkin are the most common known cause of autosomal recessive Parkinson’s disease (PD), and parkin depletion may play a role in sporadic PD. Here, we sought to elucidate the mechanisms by which stress decreases parkin protein levels using cultured neuronal cells and the PD-relevant stressor, L-DOPA. We find that L-DOPA causes parkin loss through both oxidative stress-independent and oxidative stress-dependent pathways. Characterization of the latter reveals that it requires both the kinase PINK1 and parkin’s interaction with phosphorylated ubiquitin (phospho-Ub) and is mediated by proteasomal degradation. Surprisingly, autoubiquitination and mitophagy do not appear to be required for such loss. In response to stress induced by hydrogen peroxide or CCCP, parkin degradation also requires its association with phospho-Ub, indicating that this mechanism is broadly generalizable. As oxidative stress, metabolic dysfunction and phospho-Ub levels are all elevated in PD, we suggest that these changes may contribute to a loss of parkin expression.
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Affiliation(s)
| | - Eugene V Mosharov
- Departments of Psychiatry, Neurology, and Pharmacology, Columbia University: Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA
| | - Oren A Levy
- Department of Neurology, Columbia University Medical Center, New York, NY, USA
| | - Lloyd A Greene
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA.
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Abstract
The maintenance of a healthy and functional mitochondrial network is critical during development as well as throughout life in the response to physiological adaptations and stress conditions. Owing to their role in energy production, mitochondria are exposed to high levels of reactive oxygen species, making them particularly vulnerable to mitochondrial DNA mutations and protein misfolding. Given that mitochondria are formed from proteins encoded by both nuclear and mitochondrial genomes, an additional layer of complexity is inherent in the coordination of protein synthesis and the mitochondrial import of nuclear-encoded proteins. For these reasons, mitochondria have evolved multiple systems of quality control to ensure that the requisite number of functional mitochondria are present to meet the demands of the cell. These pathways work to eliminate damaged mitochondrial proteins or parts of the mitochondrial network by mitophagy and renew components by adding protein and lipids through biogenesis, collectively resulting in mitochondrial turnover. Mitochondrial quality control mechanisms are multi-tiered, operating at the protein, organelle and cell levels. Herein, we discuss mitophagy in different physiological contexts and then relate it to other quality control pathways, including the unfolded protein response, shedding of vesicles, proteolysis, and degradation by the ubiquitin-proteasome system. Understanding how these pathways contribute to the maintenance of mitochondrial homeostasis could provide insights into the development of targeted treatments when these systems fail in disease.
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McDowell MA, Byrne AM, Mylona E, Johnson R, Sagfors A, Crepin VF, Lea S, Frankel G. The S. Typhi effector StoD is an E3/E4 ubiquitin ligase which binds K48- and K63-linked diubiquitin. Life Sci Alliance 2019; 2:2/3/e201800272. [PMID: 31142637 PMCID: PMC6545606 DOI: 10.26508/lsa.201800272] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 05/03/2019] [Accepted: 05/07/2019] [Indexed: 11/24/2022] Open
Abstract
Salmonella Typhi is estimated to cause 100,000–200,000 deaths annually, yet its infection strategy remains elusive. This article reports of the first Typhi-specific effector, which has an E3/E4 ubiquitin ligase activity and can uniquely bind K48- and K63-linked diubiquitin. Salmonella enterica (e.g., serovars Typhi and Typhimurium) relies on translocation of effectors via type III secretion systems (T3SS). Specialization of typhoidal serovars is thought to be mediated via pseudogenesis. Here, we show that the Salmonella Typhi STY1076/t1865 protein, named StoD, a homologue of the enteropathogenic Escherichia coli/enterohemorrhagic E. coli/Citrobacter rodentium NleG, is a T3SS effector. The StoD C terminus (StoD-C) is a U-box E3 ubiquitin ligase, capable of autoubiquitination in the presence of multiple E2s. The crystal structure of the StoD N terminus (StoD-N) at 2.5 Å resolution revealed a ubiquitin-like fold. In HeLa cells expressing StoD, ubiquitin is redistributed into puncta that colocalize with StoD. Binding assays showed that StoD-N and StoD-C bind the same exposed surface of the β-sheet of ubiquitin, suggesting that StoD could simultaneously interact with two ubiquitin molecules. Consistently, StoD interacted with both K63- (KD = 5.6 ± 1 μM) and K48-linked diubiquitin (KD = 15 ± 4 μM). Accordingly, we report the first S. Typhi–specific T3SS effector. We suggest that StoD recognizes and ubiquitinates pre-ubiquitinated targets, thus subverting intracellular signaling by functioning as an E4 enzyme.
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Affiliation(s)
| | - Alexander Mp Byrne
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
| | - Elli Mylona
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
| | - Rebecca Johnson
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
| | - Agnes Sagfors
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
| | - Valerie F Crepin
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
| | - Susan Lea
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Gad Frankel
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
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40
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Corti O. Neuronal Mitophagy: Lessons from a Pathway Linked to Parkinson's Disease. Neurotox Res 2019; 36:292-305. [PMID: 31102068 DOI: 10.1007/s12640-019-00060-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 04/17/2019] [Accepted: 05/06/2019] [Indexed: 02/06/2023]
Abstract
Neurons are specialized cells with complex and extended architecture and high energy requirements. Energy in the form of adenosine triphosphate, produced essentially by mitochondrial respiration, is necessary to preserve neuronal morphology, maintain resting potential, fire action potentials, and ensure neurotransmission. Pools of functional mitochondria are required in all neuronal compartments, including cell body and dendrites, nodes of Ranvier, growth cones, axons, and synapses. The mechanisms by which old or damaged mitochondria are removed and replaced in neurons remain to be fully understood. Mitophagy has gained considerable interest since the discovery of familial forms of Parkinson's disease caused by dysfunction of PINK1 and Parkin, two multifunctional proteins cooperating in the regulation of this process. Over the past 10 years, the molecular mechanisms by which PINK1 and Parkin jointly promote the degradation of defective mitochondria by autophagy have been dissected. However, our understanding of the relevance of mitophagy to mitochondrial homeostasis in neurons remains poor. Insight has been recently gained thanks to the development of fluorescent reporter systems for tracking mitochondria in the acidic compartment of the lysosome. Using these tools, mitophagy events have been visualized in primary neurons in culture and in vivo, under basal conditions and in response to toxic insults. Despite these advances, whether PINK1 and Parkin play a major role in promoting neuronal mitophagy under physiological conditions in adult animals and during aging remains a matter of debate. Future studies will have to clarify in how far dysfunction of neuronal mitophagy is central to the pathophysiology of Parkinson's disease.
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Affiliation(s)
- Olga Corti
- Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France.
- Inserm, U1127, F-75013, Paris, France.
- CNRS, UMR 7225, F-75013, Paris, France.
- Sorbonne Universités, F-75013, Paris, France.
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41
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Escobar-Henriques M, Joaquim M. Mitofusins: Disease Gatekeepers and Hubs in Mitochondrial Quality Control by E3 Ligases. Front Physiol 2019; 10:517. [PMID: 31156446 PMCID: PMC6533591 DOI: 10.3389/fphys.2019.00517] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 04/11/2019] [Indexed: 02/06/2023] Open
Abstract
Mitochondria are dynamic organelles engaged in quality control and aging processes. They constantly undergo fusion, fission, transport, and anchoring events, which empower mitochondria with a very interactive behavior. The membrane remodeling processes needed for fusion require conserved proteins named mitofusins, MFN1 and MFN2 in mammals and Fzo1 in yeast. They are the first determinants deciding on whether communication and content exchange between different mitochondrial populations should occur. Importantly, each cell possesses hundreds of mitochondria, with a different severity of mitochondrial mutations or dysfunctional proteins, which potentially spread damage to the entire network. Therefore, the degree of their merging capacity critically influences cellular fitness. In turn, the mitochondrial network rapidly and dramatically changes in response to metabolic and environmental cues. Notably, cancer or obesity conditions, and stress experienced by neurons and cardiomyocytes, for example, triggers the downregulation of mitofusins and thus fragmentation of mitochondria. This places mitofusins upfront in sensing and transmitting stress. In fact, mitofusins are almost entirely exposed to the cytoplasm, a topology suitable for a critical relay point in information exchange between mitochondria and their cellular environment. Consistent with their topology, mitofusins are either activated or repressed by cytosolic post-translational modifiers, mainly by ubiquitin. Ubiquitin is a ubiquitous small protein orchestrating multiple quality control pathways, which is covalently attached to lysine residues in its substrates, or in ubiquitin itself. Importantly, from a chain of events also mediated by E1 and E2 enzymes, E3 ligases perform the ultimate and determinant step in substrate choice. Here, we review the ubiquitin E3 ligases that modify mitofusins. Two mitochondrial E3 enzymes—March5 and MUL1—one ligase located to the ER—Gp78—and finally three cytosolic enzymes—MGRN1, HUWE1, and Parkin—were shown to ubiquitylate mitofusins, in response to a variety of cellular inputs. The respective outcomes on mitochondrial morphology, on contact sites to the endoplasmic reticulum and on destructive processes, like mitophagy or apoptosis, are presented. Ultimately, understanding the mechanisms by which E3 ligases and mitofusins sense and bi-directionally signal mitochondria-cytosolic dysfunctions could pave the way for therapeutic approaches in neurodegenerative, cardiovascular, and obesity-linked diseases.
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Affiliation(s)
- Mafalda Escobar-Henriques
- Center for Molecular Medicine Cologne (CMMC), Institute for Genetics, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Mariana Joaquim
- Center for Molecular Medicine Cologne (CMMC), Institute for Genetics, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
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42
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Abstract
The three distinct types of E3 ubiquitin ligases, RING, HECT, and RBR, employ different modes of ubiquitin transfer including E2∼Ub conjugate type and conformation. In this issue of Structure, Dove et al. (2017) provide a structural rationale for the preference and conformation of the UbcH7∼Ub conjugate by the RBR E3 ligase HHARI.
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Affiliation(s)
- Karen M Dunkerley
- Department of Biochemistry, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Gary S Shaw
- Department of Biochemistry, The University of Western Ontario, London, ON N6A 5C1, Canada.
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43
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LC3/GABARAPs drive ubiquitin-independent recruitment of Optineurin and NDP52 to amplify mitophagy. Nat Commun 2019; 10:408. [PMID: 30679426 PMCID: PMC6345886 DOI: 10.1038/s41467-019-08335-6] [Citation(s) in RCA: 156] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 12/21/2018] [Indexed: 12/17/2022] Open
Abstract
Current models of selective autophagy dictate that autophagy receptors, including Optineurin and NDP52, link cargo to autophagosomal membranes. This is thought to occur via autophagy receptor binding to Atg8 homologs (LC3/GABARAPs) through an LC3 interacting region (LIR). The LIR motif within autophagy receptors is therefore widely recognised as being essential for selective sequestration of cargo. Here we show that the LIR motif within OPTN and NDP52 is dispensable for Atg8 recruitment and selectivity during PINK1/Parkin mitophagy. Instead, Atg8s play a critical role in mediating ubiquitin-independent recruitment of OPTN and NDP52 to growing phagophore membranes via the LIR motif. The additional recruitment of OPTN and NDP52 amplifies mitophagy through an Atg8-dependent positive feedback loop. Rather than functioning in selectivity, our discovery of a role for the LIR motif in mitophagy amplification points toward a general mechanism by which Atg8s can recruit autophagy factors to drive autophagosome growth and amplify selective autophagy.
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44
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Quadri MM, Fatima SS, Che RC, Zhang AH. Mitochondria and Renal Fibrosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1165:501-524. [PMID: 31399982 DOI: 10.1007/978-981-13-8871-2_25] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mitochondria are important organelles in eukaryotic cells and perform a variety of biosynthetic and metabolic functions. Many human diseases are closely related to mitochondrial dysfunction. Kidney is an organ with high-energy requirements, which is distributed with a large number of mitochondria. Mitochondrial dysfunction plays a crucial role in the pathogenesis of kidney disease, and studies have shown that mitochondrial dysfunction is involved in the physiological process of renal fibrosis. This review introduced the biogenesis and pathophysiology of mitochondria, illustrated the involvement of mitochondrial dysfunction in renal fibrosis based on various kinds of cells, and finally summarized the latest mitochondria-targeted therapies.
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Affiliation(s)
| | - Syeda-Safoorah Fatima
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Ruo-Chen Che
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Ai-Hua Zhang
- Department of Nephrology, Children's Hospital of Nanjing Medical University, Nanjing, China.
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45
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Bernardini JP, Brouwer JM, Tan IK, Sandow JJ, Huang S, Stafford CA, Bankovacki A, Riffkin CD, Wardak AZ, Czabotar PE, Lazarou M, Dewson G. Parkin inhibits BAK and BAX apoptotic function by distinct mechanisms during mitophagy. EMBO J 2018; 38:embj.201899916. [PMID: 30573668 DOI: 10.15252/embj.201899916] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 11/08/2018] [Accepted: 11/13/2018] [Indexed: 12/26/2022] Open
Abstract
The E3 ubiquitin ligase Parkin is a key effector of the removal of damaged mitochondria by mitophagy. Parkin determines cell fate in response to mitochondrial damage, with its loss promoting early onset Parkinson's disease and potentially also cancer progression. Controlling a cell's apoptotic response is essential to co-ordinate the removal of damaged mitochondria. We report that following mitochondrial damage-induced mitophagy, Parkin directly ubiquitinates the apoptotic effector protein BAK at a conserved lysine in its hydrophobic groove, a region that is crucial for BAK activation by BH3-only proteins and its homo-dimerisation during apoptosis. Ubiquitination inhibited BAK activity by impairing its activation and the formation of lethal BAK oligomers. Parkin also suppresses BAX-mediated apoptosis, but in the absence of BAX ubiquitination suggesting an indirect mechanism. In addition, we find that BAK-dependent mitochondrial outer membrane permeabilisation during apoptosis promotes PINK1-dependent Parkin activation. Hence, we propose that Parkin directly inhibits BAK to suppress errant apoptosis, thereby allowing the effective clearance of damaged mitochondria, but also promotes clearance of apoptotic mitochondria to limit their potential pro-inflammatory effect.
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Affiliation(s)
- Jonathan P Bernardini
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia.,Department of Medical Biology, University of Melbourne, Parkville, Melbourne, Vic., Australia
| | - Jason M Brouwer
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia.,Department of Medical Biology, University of Melbourne, Parkville, Melbourne, Vic., Australia
| | - Iris Kl Tan
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia
| | - Jarrod J Sandow
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia.,Department of Medical Biology, University of Melbourne, Parkville, Melbourne, Vic., Australia
| | - Shuai Huang
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia.,Department of Medical Biology, University of Melbourne, Parkville, Melbourne, Vic., Australia
| | - Che A Stafford
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia.,Department of Medical Biology, University of Melbourne, Parkville, Melbourne, Vic., Australia
| | - Aleksandra Bankovacki
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia
| | - Christopher D Riffkin
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia
| | - Ahmad Z Wardak
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia
| | - Peter E Czabotar
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia.,Department of Medical Biology, University of Melbourne, Parkville, Melbourne, Vic., Australia
| | - Michael Lazarou
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute Monash University, Clayton, Melbourne, Vic., Australia
| | - Grant Dewson
- Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, Vic., Australia .,Department of Medical Biology, University of Melbourne, Parkville, Melbourne, Vic., Australia
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46
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Condos TE, Dunkerley KM, Freeman EA, Barber KR, Aguirre JD, Chaugule VK, Xiao Y, Konermann L, Walden H, Shaw GS. Synergistic recruitment of UbcH7~Ub and phosphorylated Ubl domain triggers parkin activation. EMBO J 2018; 37:embj.2018100014. [PMID: 30446597 PMCID: PMC6276879 DOI: 10.15252/embj.2018100014] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 10/25/2018] [Accepted: 10/26/2018] [Indexed: 12/05/2022] Open
Abstract
The E3 ligase parkin ubiquitinates outer mitochondrial membrane proteins during oxidative stress and is linked to early‐onset Parkinson's disease. Parkin is autoinhibited but is activated by the kinase PINK1 that phosphorylates ubiquitin leading to parkin recruitment, and stimulates phosphorylation of parkin's N‐terminal ubiquitin‐like (pUbl) domain. How these events alter the structure of parkin to allow recruitment of an E2~Ub conjugate and enhanced ubiquitination is an unresolved question. We present a model of an E2~Ub conjugate bound to the phospho‐ubiquitin‐loaded C‐terminus of parkin, derived from NMR chemical shift perturbation experiments. We show the UbcH7~Ub conjugate binds in the open state whereby conjugated ubiquitin binds to the RING1/IBR interface. Further, NMR and mass spectrometry experiments indicate the RING0/RING2 interface is re‐modelled, remote from the E2 binding site, and this alters the reactivity of the RING2(Rcat) catalytic cysteine, needed for ubiquitin transfer. Our experiments provide evidence that parkin phosphorylation and E2~Ub recruitment act synergistically to enhance a weak interaction of the pUbl domain with the RING0 domain and rearrange the location of the RING2(Rcat) domain to drive parkin activity.
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Affiliation(s)
- Tara Ec Condos
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
| | - Karen M Dunkerley
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
| | - E Aisha Freeman
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
| | - Kathryn R Barber
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
| | - Jacob D Aguirre
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
| | - Viduth K Chaugule
- Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow, UK
| | - Yiming Xiao
- Department of Chemistry, The University of Western Ontario, London, ON, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, ON, Canada
| | - Helen Walden
- Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow, UK
| | - Gary S Shaw
- Department of Biochemistry, The University of Western Ontario, London, ON, Canada
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47
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McWilliams TG, Barini E, Pohjolan-Pirhonen R, Brooks SP, Singh F, Burel S, Balk K, Kumar A, Montava-Garriga L, Prescott AR, Hassoun SM, Mouton-Liger F, Ball G, Hills R, Knebel A, Ulusoy A, Di Monte DA, Tamjar J, Antico O, Fears K, Smith L, Brambilla R, Palin E, Valori M, Eerola-Rautio J, Tienari P, Corti O, Dunnett SB, Ganley IG, Suomalainen A, Muqit MMK. Phosphorylation of Parkin at serine 65 is essential for its activation in vivo. Open Biol 2018; 8:rsob.180108. [PMID: 30404819 PMCID: PMC6282074 DOI: 10.1098/rsob.180108] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mutations in PINK1 and Parkin result in autosomal recessive Parkinson's disease (PD). Cell culture and in vitro studies have elaborated the PINK1-dependent regulation of Parkin and defined how this dyad orchestrates the elimination of damaged mitochondria via mitophagy. PINK1 phosphorylates ubiquitin at serine 65 (Ser65) and Parkin at an equivalent Ser65 residue located within its N-terminal ubiquitin-like domain, resulting in activation; however, the physiological significance of Parkin Ser65 phosphorylation in vivo in mammals remains unknown. To address this, we generated a Parkin Ser65Ala (S65A) knock-in mouse model. We observe endogenous Parkin Ser65 phosphorylation and activation in mature primary neurons following mitochondrial depolarization and reveal this is disrupted in Parkin S65A/S65A neurons. Phenotypically, Parkin S65A/S65A mice exhibit selective motor dysfunction in the absence of any overt neurodegeneration or alterations in nigrostriatal mitophagy. The clinical relevance of our findings is substantiated by the discovery of homozygous PARKIN (PARK2) p.S65N mutations in two unrelated patients with PD. Moreover, biochemical and structural analysis demonstrates that the ParkinS65N/S65N mutant is pathogenic and cannot be activated by PINK1. Our findings highlight the central role of Parkin Ser65 phosphorylation in health and disease.
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Affiliation(s)
- Thomas G McWilliams
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK .,Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland
| | - Erica Barini
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Risto Pohjolan-Pirhonen
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, 00290 Helsinki, Finland.,Helsinki University Hospital, 00290 Helsinki, Finland
| | - Simon P Brooks
- The Brain Repair Group, Division of Neuroscience, School of Biosciences, Cardiff University, Wales CF10 3AX, UK
| | - François Singh
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Sophie Burel
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Kristin Balk
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Atul Kumar
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Lambert Montava-Garriga
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Alan R Prescott
- Dundee Imaging Facility, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | | | | | - Graeme Ball
- Dundee Imaging Facility, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Rachel Hills
- The Brain Repair Group, Division of Neuroscience, School of Biosciences, Cardiff University, Wales CF10 3AX, UK
| | - Axel Knebel
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Ayse Ulusoy
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | | | - Jevgenia Tamjar
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Odetta Antico
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Kyle Fears
- The Brain Repair Group, Division of Neuroscience, School of Biosciences, Cardiff University, Wales CF10 3AX, UK
| | - Laura Smith
- The Brain Repair Group, Division of Neuroscience, School of Biosciences, Cardiff University, Wales CF10 3AX, UK
| | - Riccardo Brambilla
- Neuroscience & Mental Health Institute, Neuroscience Division, School of Biosciences, Hadyn Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK
| | - Eino Palin
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, 00290 Helsinki, Finland.,Helsinki University Hospital, 00290 Helsinki, Finland
| | - Miko Valori
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, 00290 Helsinki, Finland.,Helsinki University Hospital, 00290 Helsinki, Finland
| | - Johanna Eerola-Rautio
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, 00290 Helsinki, Finland.,Helsinki University Hospital, 00290 Helsinki, Finland.,Department of Neurology, Helsinki University Hospital, Haartmaninkatu 4, Helsinki, FI 00290, Finland
| | - Pentti Tienari
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, 00290 Helsinki, Finland.,Helsinki University Hospital, 00290 Helsinki, Finland
| | | | - Stephen B Dunnett
- The Brain Repair Group, Division of Neuroscience, School of Biosciences, Cardiff University, Wales CF10 3AX, UK
| | - Ian G Ganley
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Anu Suomalainen
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland.,Neuroscience Center, University of Helsinki, 00290 Helsinki, Finland.,Helsinki University Hospital, 00290 Helsinki, Finland
| | - Miratul M K Muqit
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK .,School of Medicine, University of Dundee, Dundee DD1 9SY, UK
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48
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Zhu M, Cortese GP, Waites CL. Parkinson's disease-linked Parkin mutations impair glutamatergic signaling in hippocampal neurons. BMC Biol 2018; 16:100. [PMID: 30200940 PMCID: PMC6130078 DOI: 10.1186/s12915-018-0567-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 08/24/2018] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Parkinson's disease (PD)-associated E3 ubiquitin ligase Parkin is enriched at glutamatergic synapses, where it ubiquitinates multiple substrates, suggesting that its mutation/loss-of-function could contribute to the etiology of PD by disrupting excitatory neurotransmission. Here, we evaluate the impact of four common PD-associated Parkin point mutations (T240M, R275W, R334C, G430D) on glutamatergic synaptic function in hippocampal neurons. RESULTS We find that expression of these point mutants in cultured hippocampal neurons from Parkin-deficient and Parkin-null backgrounds alters NMDA and AMPA receptor-mediated currents and cell-surface levels and prevents the induction of long-term depression. Mechanistically, we demonstrate that Parkin regulates NMDA receptor trafficking through its ubiquitination of GluN1, and that all four mutants are impaired in this ubiquitinating activity. Furthermore, Parkin regulates synaptic AMPA receptor trafficking via its binding and retention of the postsynaptic scaffold Homer1, and all mutants are similarly impaired in this capacity. CONCLUSION Our findings demonstrate that pathogenic Parkin mutations disrupt glutamatergic synaptic transmission in hippocampal neurons by impeding NMDA and AMPA receptor trafficking. Such effects may contribute to the pathophysiology of PD in PARK2 patients.
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Affiliation(s)
- Mei Zhu
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032 USA
| | - Giuseppe P. Cortese
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032 USA
- Department of Psychiatry, Columbia University Medical Center, New York, NY USA
| | - Clarissa L. Waites
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032 USA
- Department of Neuroscience, Columbia University, New York, NY USA
- Waites Lab, 650 W. 168th St. Black Building 1210B, New York, NY 10032 USA
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49
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Mechanisms of mitophagy in cellular homeostasis, physiology and pathology. Nat Cell Biol 2018; 20:1013-1022. [PMID: 30154567 DOI: 10.1038/s41556-018-0176-2] [Citation(s) in RCA: 834] [Impact Index Per Article: 139.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 07/25/2018] [Indexed: 02/06/2023]
Abstract
Mitophagy is an evolutionarily conserved cellular process to remove dysfunctional or superfluous mitochondria, thus fine-tuning mitochondrial number and preserving energy metabolism. In this Review, we survey recent advances towards elucidating the molecular mechanisms that mediate mitochondrial elimination and the signalling pathways that govern mitophagy. We consider the contributions of mitophagy in physiological and pathological contexts and discuss emerging findings, highlighting the potential value of mitophagy modulation in therapeutic intervention.
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50
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Xia X, Katzenell S, Reinhart EF, Bauer KM, Pellegrini M, Ragusa MJ. A pseudo-receiver domain in Atg32 is required for mitophagy. Autophagy 2018; 14:1620-1628. [PMID: 29909755 DOI: 10.1080/15548627.2018.1472838] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
Mitochondria are targeted for degradation by mitophagy, a selective form of autophagy. In Saccharomyces cerevisiae, mitophagy is dependent on the autophagy receptor, Atg32, an outer mitochondrial membrane protein. Once activated, Atg32 recruits the autophagy machinery to mitochondria, facilitating mitochondrial capture in phagophores, the precursors to autophagosomes. However, the mechanism of Atg32 activation remains poorly understood. To investigate this crucial step in mitophagy regulation, we examined the structure of Atg32. We have identified a structured domain in Atg32 that is essential for the initiation of mitophagy, as it is required for the proteolysis of the C-terminal domain of Atg32 and the subsequent recruitment of Atg11. The solution structure of this domain was determined by NMR spectroscopy, revealing that Atg32 contains a previously undescribed pseudo-receiver (PsR) domain. Our data suggests that the PsR domain of Atg32 regulates Atg32 activation and the initiation of mitophagy. ABBREVIATIONS AIM: Atg8-interacting motif; GFP: green fluorescent protein; LIR: LC3-interacting region; NMR: nuclear magnetic resonance; NOESY: nuclear Overhauser effect spectroscopy; PDB: protein data bank; PsR: pseudo-receiver; RMSD: root-mean-square deviation.
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Affiliation(s)
- Xue Xia
- a Department of Biochemistry & Cell Biology , Geisel School of Medicine at Dartmouth , Hanover , NH , USA
| | - Sarah Katzenell
- b Department of Chemistry , Dartmouth College , Hanover , NH , USA
| | - Erin F Reinhart
- b Department of Chemistry , Dartmouth College , Hanover , NH , USA
| | - Katherine M Bauer
- a Department of Biochemistry & Cell Biology , Geisel School of Medicine at Dartmouth , Hanover , NH , USA
| | - Maria Pellegrini
- b Department of Chemistry , Dartmouth College , Hanover , NH , USA
| | - Michael J Ragusa
- a Department of Biochemistry & Cell Biology , Geisel School of Medicine at Dartmouth , Hanover , NH , USA.,b Department of Chemistry , Dartmouth College , Hanover , NH , USA
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