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Sultana S, Abdullah M, Li J, Hochstrasser M, Kachroo AH. Species-specific protein-protein interactions govern the humanization of the 20S proteasome in yeast. Genetics 2023; 225:iyad117. [PMID: 37364278 PMCID: PMC10471208 DOI: 10.1093/genetics/iyad117] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/12/2023] [Accepted: 06/15/2023] [Indexed: 06/28/2023] Open
Abstract
Yeast and humans share thousands of genes despite a billion years of evolutionary divergence. While many human genes can functionally replace their yeast counterparts, nearly half of the tested shared genes cannot. For example, most yeast proteasome subunits are "humanizable," except subunits comprising the β-ring core, including β2c (HsPSMB7, a constitutive proteasome subunit). We developed a high-throughput pipeline to humanize yeast proteasomes by generating a large library of Hsβ2c mutants and screening them for complementation of a yeast β2 (ScPup1) knockout. Variants capable of replacing ScPup1 included (1) those impacting local protein-protein interactions (PPIs), with most affecting interactions between the β2c C-terminal tail and the adjacent β3 subunit, and (2) those affecting β2c proteolytic activity. Exchanging the full-length tail of human β2c with that of ScPup1 enabled complementation. Moreover, wild-type human β2c could replace yeast β2 if human β3 was also provided. Unexpectedly, yeast proteasomes bearing a catalytically inactive HsPSMB7-T44A variant that blocked precursor autoprocessing were viable, suggesting an intact propeptide stabilizes late assembly intermediates. In contrast, similar modifications in human β2i (HsPSMB10), an immunoproteasome subunit and the co-ortholog of yeast β2, do not enable complementation in yeast, suggesting distinct interactions are involved in human immunoproteasome core assembly. Broadly, our data reveal roles for specific PPIs governing functional replaceability across vast evolutionary distances.
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Affiliation(s)
- Sarmin Sultana
- Centre for Applied Synthetic Biology, Department of Biology, Concordia University, 7141 Sherbrooke St. W, Montreal, QC H3G 1M8, Canada
| | - Mudabir Abdullah
- Centre for Applied Synthetic Biology, Department of Biology, Concordia University, 7141 Sherbrooke St. W, Montreal, QC H3G 1M8, Canada
| | - Jianhui Li
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Mark Hochstrasser
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Aashiq H Kachroo
- Centre for Applied Synthetic Biology, Department of Biology, Concordia University, 7141 Sherbrooke St. W, Montreal, QC H3G 1M8, Canada
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2
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Anthony AJ, Gautam AKS, Miller LM, Ma Y, Hardwick AG, Sharma A, Ghatak S, Matouschek A, Jarrold MF, Clemmer DE. CDMS Analysis of Intact 19S, 20S, 26S, and 30S Proteasomes: Evidence for Higher-Order 20S Assemblies at a Low pH†. Anal Chem 2023; 95:12209-12215. [PMID: 37552619 PMCID: PMC10916762 DOI: 10.1021/acs.analchem.3c00472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
Charge detection mass spectrometry (CDMS) was examined as a means of studying proteasomes. To this end, the following masses of the 20S, 19S, 26S, and 30S proteasomes from Saccharomyces cerevisiae (budding yeast) were measured: m(20S) = 738.8 ± 2.9 kDa, m(19S) = 926.2 ± 4.8 kDa, m(26S) = 1,637.0 ± 7.6 kDa, and m(30S) = 2,534.2 ± 10.8 kDa. Under some conditions, larger (20S)x (where x = 1 to ∼13) assemblies are observed; the 19S regulatory particle also oligomerizes, but to a lesser extent, forming (19S)x complexes (where x = 1 to 4, favoring the x = 3 trimer). The (20S)x oligomers are favored in vitro, as the pH of the solution is lowered (from 7.0 to 5.4, in a 20 mM ammonium acetate solution) and may be related to in vivo proteasome storage granules that are observed under carbon starvation. From measurements of m(20S)x (x = 1 to ∼13) species, it appears that each multimer retains all 28 proteins of the 20S complex subunit. Several types of structures that might explain the formation of (20S)x assemblies are considered. We stress that each structural type [hypothetical planar, raft-like geometries (where individual proteasomes associate through side-by-side interactions); elongated, rodlike geometries (where subunits are bound end-to-end); and geometries that are roughly spherical (arising from aggregation through nonspecific subunit interactions)] is highly speculative but still interesting to consider, and a short discussion is provided. The utility of CDMS for characterizing proteasomes and related oligomers is discussed.
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Affiliation(s)
- Adam J Anthony
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, United States
| | - Amit K S Gautam
- Department of Molecular Biosciences, University of Texas, Austin Texas 78712, United States
| | - Lohra M Miller
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, United States
| | - Yiran Ma
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, United States
| | - Anya G Hardwick
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, United States
| | - Anu Sharma
- Indiana Center for Regenerative Medicine & Engineering, Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202, United States
| | - Subhadip Ghatak
- Indiana Center for Regenerative Medicine & Engineering, Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202, United States
| | - Andreas Matouschek
- Department of Molecular Biosciences, University of Texas, Austin Texas 78712, United States
| | - Martin F Jarrold
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, United States
| | - David E Clemmer
- Department of Chemistry, Indiana University, Bloomington, Indiana 47401, United States
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3
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Kitamura H. Ubiquitin-Specific Proteases (USPs) and Metabolic Disorders. Int J Mol Sci 2023; 24:3219. [PMID: 36834633 PMCID: PMC9966627 DOI: 10.3390/ijms24043219] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 02/10/2023] Open
Abstract
Ubiquitination and deubiquitination are reversible processes that modify the characteristics of target proteins, including stability, intracellular localization, and enzymatic activity. Ubiquitin-specific proteases (USPs) constitute the largest deubiquitinating enzyme family. To date, accumulating evidence indicates that several USPs positively and negatively affect metabolic diseases. USP22 in pancreatic β-cells, USP2 in adipose tissue macrophages, USP9X, 20, and 33 in myocytes, USP4, 7, 10, and 18 in hepatocytes, and USP2 in hypothalamus improve hyperglycemia, whereas USP19 in adipocytes, USP21 in myocytes, and USP2, 14, and 20 in hepatocytes promote hyperglycemia. In contrast, USP1, 5, 9X, 14, 15, 22, 36, and 48 modulate the progression of diabetic nephropathy, neuropathy, and/or retinopathy. USP4, 10, and 18 in hepatocytes ameliorates non-alcoholic fatty liver disease (NAFLD), while hepatic USP2, 11, 14, 19, and 20 exacerbate it. The roles of USP7 and 22 in hepatic disorders are controversial. USP9X, 14, 17, and 20 in vascular cells are postulated to be determinants of atherosclerosis. Moreover, mutations in the Usp8 and Usp48 loci in pituitary tumors cause Cushing syndrome. This review summarizes the current knowledge about the modulatory roles of USPs in energy metabolic disorders.
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Affiliation(s)
- Hiroshi Kitamura
- Laboratory of Comparative Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan
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4
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A Plasmodium falciparum ubiquitin-specific protease (PfUSP) is essential for parasite survival and its disruption enhances artemisinin efficacy. Biochem J 2023; 480:25-39. [PMID: 36511651 DOI: 10.1042/bcj20220429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 12/09/2022] [Accepted: 12/13/2022] [Indexed: 12/14/2022]
Abstract
Proteins associated with ubiquitin-proteasome system (UPS) are potential drug targets in the malaria parasite. The ubiquitination and deubiquitination are key regulatory processes for the functioning of UPS. In this study, we have characterized the biochemical and functional role of a novel ubiquitin-specific protease (USP) domain-containing protein of the human malaria parasite Plasmodium falciparum (PfUSP). We have shown that the PfUSP is an active deubiquitinase associated with parasite endoplasmic reticulum (ER). Selection linked integration (SLI) method for C-terminal tagging and GlmS-ribozyme mediated inducible knock-down (iKD) of PfUSP was utilized to assess its functional role. Inducible knockdown of PfUSP resulted in a remarkable reduction in parasite growth and multiplication; specifically, PfUSP-iKD disrupted ER morphology and development, blocked the development of healthy schizonts, and hindered proper merozoite development. PfUSP-iKD caused increased ubiquitylation of specific proteins, disrupted organelle homeostasis and reduced parasite survival. Since the mode of action of artemisinin and the artemisinin-resistance are shown to be associated with the proteasome machinery, we analyzed the effect of dihydroartemisinin (DHA) on PfUSP-iKD parasites. Importantly, the PfUSP-knocked-down parasite showed increased sensitivity to dihydroartemisinin (DHA), whereas no change in chloroquine sensitivity was observed, suggesting a role of PfUSP in combating artemisinin-induced cellular stress. Together, the results show that Plasmodium PfUSP is an essential protease for parasite survival, and its inhibition increases the efficacy of artemisinin-based drugs. Therefore, PfUSP can be targeted to develop novel scaffolds for developing new antimalarials to combat artemisinin resistance.
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5
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Molecular and cellular dynamics of the 26S proteasome. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1869:140583. [PMID: 33321258 DOI: 10.1016/j.bbapap.2020.140583] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 12/07/2020] [Accepted: 12/09/2020] [Indexed: 01/16/2023]
Abstract
In eukaryotic cells, the ubiquitin-proteasome system serves to remove proteins that are either dysfunctional or no longer needed. The 26S proteasome is a 2.5 MDa multisubunit complex comprising the 20S core particle, where degradation is executed, and one or two regulatory particles which prepare substrates for degradation. Whereas the 20S core particles of several species had been studied extensively by X-ray crystallography, the 26S holocomplex structure had remained elusive for a long time. Recent advances in single-particle cryo-electron microscopy have changed the situation and provided atomic resolution models of this intriguing molecular machine and its dynamics. Besides, cryo-electron tomography enables structural studies in situ, providing molecular resolution images of macromolecules inside pristinely preserved cellular environments. This has greatly contributed to our understanding of proteasome dynamics in the context of cells.
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Suresh HG, Pascoe N, Andrews B. The structure and function of deubiquitinases: lessons from budding yeast. Open Biol 2020; 10:200279. [PMID: 33081638 PMCID: PMC7653365 DOI: 10.1098/rsob.200279] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Protein ubiquitination is a key post-translational modification that regulates diverse cellular processes in eukaryotic cells. The specificity of ubiquitin (Ub) signalling for different bioprocesses and pathways is dictated by the large variety of mono-ubiquitination and polyubiquitination events, including many possible chain architectures. Deubiquitinases (DUBs) reverse or edit Ub signals with high sophistication and specificity, forming an integral arm of the Ub signalling machinery, thus impinging on fundamental cellular processes including DNA damage repair, gene expression, protein quality control and organellar integrity. In this review, we discuss the many layers of DUB function and regulation, with a focus on insights gained from budding yeast. Our review provides a framework to understand key aspects of DUB biology.
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Affiliation(s)
- Harsha Garadi Suresh
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1
| | - Natasha Pascoe
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 3E1
| | - Brenda Andrews
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada M5S 3E1.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 3E1
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7
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Selective Degradation of Target Proteins by Chimeric Small-Molecular Drugs, PROTACs and SNIPERs. Pharmaceuticals (Basel) 2020; 13:ph13040074. [PMID: 32326273 PMCID: PMC7243126 DOI: 10.3390/ph13040074] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/17/2020] [Accepted: 04/19/2020] [Indexed: 12/16/2022] Open
Abstract
New therapeutic modalities are needed to address the problem of pathological but undruggable proteins. One possible approach is the induction of protein degradation by chimeric drugs composed of a ubiquitin ligase (E3) ligand coupled to a ligand for the target protein. This article reviews chimeric drugs that decrease the level of specific proteins such as proteolysis targeting chimeric molecules (PROTACs) and specific and nongenetic inhibitor of apoptosis protein (IAP)-dependent protein erasers (SNIPERs), which target proteins for proteasome-mediated degradation. We cover strategies for increasing the degradation activity induced by small molecules, and their scope for application to undruggable proteins.
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8
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The proteasome 19S cap and its ubiquitin receptors provide a versatile recognition platform for substrates. Nat Commun 2020; 11:477. [PMID: 31980598 PMCID: PMC6981147 DOI: 10.1038/s41467-019-13906-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 11/20/2019] [Indexed: 01/28/2023] Open
Abstract
Proteins are targeted to the proteasome by the attachment of ubiquitin chains, which are markedly varied in structure. Three proteasome subunits–Rpn10, Rpn13, and Rpn1–can recognize ubiquitin chains. Here we report that proteins with single chains of K48-linked ubiquitin are targeted for degradation almost exclusively through binding to Rpn10. Rpn1 can act as a co-receptor with Rpn10 for K63 chains and for certain other chain types. Differences in targeting do not correlate with chain affinity to receptors. Surprisingly, in steady-state assays Rpn13 retarded degradation of various single-chain substrates. Substrates with multiple short ubiquitin chains can be presented for degradation by any of the known receptors, whereas those targeted to the proteasome through a ubiquitin-like domain are degraded most efficiently when bound by Rpn13 or Rpn1. Thus, the proteasome provides an unexpectedly versatile binding platform that can recognize substrates targeted for degradation by ubiquitin chains differing greatly in length and topology. Ubiquitylated proteins are degraded by the proteasome and the three proteasome subunits Rpn10, Rpn13 and Rpn1 recognize ubiquitin chains. Here the authors employ biochemical and kinetic assays and characterise the ubiquitin chain type specificities of these three ubiquitin receptors.
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9
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Karmon O, Ben Aroya S. Spatial Organization of Proteasome Aggregates in the Regulation of Proteasome Homeostasis. Front Mol Biosci 2020; 6:150. [PMID: 31998748 PMCID: PMC6962763 DOI: 10.3389/fmolb.2019.00150] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 12/06/2019] [Indexed: 12/23/2022] Open
Abstract
Misfolded proteins and insoluble aggregates are continuously produced in the cell and can result in severe stress that threatens cellular fitness and viability if not managed effectively. Accordingly, organisms have evolved several protective protein quality control (PQC) machineries to address these threats. In eukaryotes, the ubiquitin–proteasome system (UPS) plays a vital role in the disposal of intracellular misfolded, damaged, or unneeded proteins. Although ubiquitin-mediated proteasomal degradation of many proteins plays a key role in the PQC system, cells must also dispose of the proteasomes themselves when their subunits are assembled improperly, or when they dysfunction under various conditions, e.g., as a result of genomic mutations, diverse stresses, or treatment with proteasome inhibitors. Here, we review recent studies that identified the regulatory pathways that mediate proteasomes sorting under various stress conditions, and the elimination of its dysfunctional subunits. Following inactivation of the 26S proteasome, UPS-mediated degradation of its own misassembled subunits is the favored disposal pathway. However, the cytosolic cell-compartment-specific aggregase, Hsp42 mediates an alternative pathway, the accumulation of these subunits in cytoprotective compartments, where they become extensively modified with ubiquitin, and are directed by ubiquitin receptors for autophagic clearance (proteaphagy). We also discuss the sorting mechanisms that the cell uses under nitrogen stress, and to distinguish between dysfunctional proteasome aggregates and proteasome storage granules (PSGs), reversible assemblies of membrane-free cytoplasmic condensates that form in yeast upon carbon starvation and help protect proteasomes from autophagic degradation. Regulated proteasome subunit homeostasis is thus controlled through cellular probing of the level of proteasome assembly, and the interplay between UPS-mediated degradation or sorting of misfolded proteins into distinct cellular compartments.
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Affiliation(s)
- Ofri Karmon
- The Mina and Everard Goodman, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Shay Ben Aroya
- The Mina and Everard Goodman, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
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10
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Mendes ML, Fischer L, Chen ZA, Barbon M, O'Reilly FJ, Giese SH, Bohlke‐Schneider M, Belsom A, Dau T, Combe CW, Graham M, Eisele MR, Baumeister W, Speck C, Rappsilber J. An integrated workflow for crosslinking mass spectrometry. Mol Syst Biol 2019; 15:e8994. [PMID: 31556486 PMCID: PMC6753376 DOI: 10.15252/msb.20198994] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/19/2019] [Accepted: 08/21/2019] [Indexed: 11/09/2022] Open
Abstract
We present a concise workflow to enhance the mass spectrometric detection of crosslinked peptides by introducing sequential digestion and the crosslink identification software xiSEARCH. Sequential digestion enhances peptide detection by selective shortening of long tryptic peptides. We demonstrate our simple 12-fraction protocol for crosslinked multi-protein complexes and cell lysates, quantitative analysis, and high-density crosslinking, without requiring specific crosslinker features. This overall approach reveals dynamic protein-protein interaction sites, which are accessible, have fundamental functional relevance and are therefore ideally suited for the development of small molecule inhibitors.
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Affiliation(s)
- Marta L Mendes
- BioanalyticsInstitute of BiotechnologyTechnische Universität BerlinBerlinGermany
- Present address:
Quantitative Biology UnitLuxembourg Institute of HealthLuxembourgLuxembourg
| | - Lutz Fischer
- BioanalyticsInstitute of BiotechnologyTechnische Universität BerlinBerlinGermany
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
| | - Zhuo A Chen
- BioanalyticsInstitute of BiotechnologyTechnische Universität BerlinBerlinGermany
| | - Marta Barbon
- MRC London Institute of Medical Sciences (LMS)LondonUK
- DNA Replication GroupFaculty of MedicineInstitute of Clinical Sciences (ICS)Imperial College LondonLondonUK
| | - Francis J O'Reilly
- BioanalyticsInstitute of BiotechnologyTechnische Universität BerlinBerlinGermany
| | - Sven H Giese
- BioanalyticsInstitute of BiotechnologyTechnische Universität BerlinBerlinGermany
| | | | - Adam Belsom
- BioanalyticsInstitute of BiotechnologyTechnische Universität BerlinBerlinGermany
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
| | - Therese Dau
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
| | - Colin W Combe
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
| | - Martin Graham
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
| | - Markus R Eisele
- Department of Molecular Structural BiologyMax Planck Institute of BiochemistryMartinsriedGermany
| | - Wolfgang Baumeister
- Department of Molecular Structural BiologyMax Planck Institute of BiochemistryMartinsriedGermany
| | - Christian Speck
- MRC London Institute of Medical Sciences (LMS)LondonUK
- DNA Replication GroupFaculty of MedicineInstitute of Clinical Sciences (ICS)Imperial College LondonLondonUK
| | - Juri Rappsilber
- BioanalyticsInstitute of BiotechnologyTechnische Universität BerlinBerlinGermany
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
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11
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Ngounou Wetie AG, Sokolowska I, Channaveerappa D, Dupree EJ, Jayathirtha M, Woods AG, Darie CC. Proteomics and Non-proteomics Approaches to Study Stable and Transient Protein-Protein Interactions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1140:121-142. [DOI: 10.1007/978-3-030-15950-4_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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12
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Ubiquitin-dependent switch during assembly of the proteasomal ATPases mediated by Not4 ubiquitin ligase. Proc Natl Acad Sci U S A 2018; 115:13246-13251. [PMID: 30530678 DOI: 10.1073/pnas.1805353115] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In the proteasome holoenzyme, the hexameric ATPases (Rpt1-Rpt6) enable degradation of ubiquitinated proteins by unfolding and translocating them into the proteolytic core particle. During early-stage proteasome assembly, individual Rpt proteins assemble into the hexameric "Rpt ring" through binding to their cognate chaperones: Nas2, Hsm3, Nas6, and Rpn14. Here, we show that Rpt ring assembly employs a specific ubiquitination-mediated control. An E3 ligase, Not4, selectively ubiquitinates Rpt5 during Rpt ring assembly. To access Rpt5, Not4 competes with Nas2 until the penultimate step and then with Hsm3 at the final step of Rpt ring completion. Using the known Rpt-chaperone cocrystal structures, we show that Not4-mediated ubiquitination sites in Rpt5 are obstructed by Nas2 and Hsm3. Thus, Not4 can distinguish a Rpt ring that matures without these chaperones, based on its accessibility to Rpt5. Rpt5 ubiquitination does not destabilize the ring but hinders incorporation of incoming subunits-Rpn1 ubiquitin receptor and Ubp6 deubiquitinase-thereby blocking progression of proteasome assembly and ubiquitin regeneration from proteasome substrates. Our findings reveal an assembly checkpoint where Not4 monitors chaperone actions during hexameric ATPase ring assembly, thereby ensuring the accuracy of proteasome holoenzyme maturation.
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13
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van de Waterbeemd M, Tamara S, Fort KL, Damoc E, Franc V, Bieri P, Itten M, Makarov A, Ban N, Heck AJR. Dissecting ribosomal particles throughout the kingdoms of life using advanced hybrid mass spectrometry methods. Nat Commun 2018; 9:2493. [PMID: 29950687 PMCID: PMC6021402 DOI: 10.1038/s41467-018-04853-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/28/2018] [Indexed: 11/08/2022] Open
Abstract
Biomolecular mass spectrometry has matured strongly over the past decades and has now reached a stage where it can provide deep insights into the structure and composition of large cellular assemblies. Here, we describe a three-tiered hybrid mass spectrometry approach that enables the dissection of macromolecular complexes in order to complement structural studies. To demonstrate the capabilities of the approach, we investigate ribosomes, large ribonucleoprotein particles consisting of a multitude of protein and RNA subunits. We identify sites of sequence processing, protein post-translational modifications, and the assembly and stoichiometry of individual ribosomal proteins in four distinct ribosomal particles of bacterial, plant and human origin. Amongst others, we report extensive cysteine methylation in the zinc finger domain of the human S27 protein, the heptameric stoichiometry of the chloroplastic stalk complex, the heterogeneous composition of human 40S ribosomal subunits and their association to the CrPV, and HCV internal ribosome entry site RNAs.
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Affiliation(s)
- Michiel van de Waterbeemd
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands
| | - Sem Tamara
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands
| | - Kyle L Fort
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands
- Thermo Fisher Scientific, 28199, Bremen, Germany
| | - Eugen Damoc
- Thermo Fisher Scientific, 28199, Bremen, Germany
| | - Vojtech Franc
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands
| | - Philipp Bieri
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, 8093, Zurich, Switzerland
| | - Martin Itten
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, 8093, Zurich, Switzerland
| | - Alexander Makarov
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands
- Thermo Fisher Scientific, 28199, Bremen, Germany
| | - Nenad Ban
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, 8093, Zurich, Switzerland
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, 3584CH, The Netherlands.
- Netherlands Proteomics Center, 3584CH, Utrecht, The Netherlands.
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14
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de Poot SAH, Tian G, Finley D. Meddling with Fate: The Proteasomal Deubiquitinating Enzymes. J Mol Biol 2017; 429:3525-3545. [PMID: 28988953 DOI: 10.1016/j.jmb.2017.09.015] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/20/2017] [Accepted: 09/26/2017] [Indexed: 01/06/2023]
Abstract
Three deubiquitinating enzymes-Rpn11, Usp14, and Uch37-are associated with the proteasome regulatory particle. These enzymes allow proteasomes to remove ubiquitin from substrates before they are translocated into the core particle to be degraded. Although the translocation channel is too narrow for folded proteins, the force of translocation unfolds them mechanically. As translocation proceeds, ubiquitin chains bound to substrate are drawn to the channel's entry port, where they can impede further translocation. Rpn11, situated over the port, can remove these chains without compromising degradation because substrates must be irreversibly committed to degradation before Rpn11 acts. This coupling between deubiquitination and substrate degradation is ensured by the Ins-1 loop of Rpn11, which controls ubiquitin access to its catalytic site. In contrast to Rpn11, Usp14 and Uch37 can rescue substrates from degradation by promoting substrate dissociation from the proteasome prior to the commitment step. Uch37 is unique in being a component of both the proteasome and a second multisubunit assembly, the INO80 complex. However, only recruitment into the proteasome activates Uch37. Recruitment to the proteasome likewise activates Usp14. However, the influence of Usp14 on the proteasome depends on the substrate, due to its marked preference for proteins that carry multiple ubiquitin chains. Usp14 exerts complex control over the proteasome, suppressing proteasome activity even when inactive in deubiquitination. A major challenge for the field will be to elucidate the specificities of Rpn11, Usp14, and Uch37 in greater depth, employing not only model in vitro substrates but also their endogenous targets.
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Affiliation(s)
- Stefanie A H de Poot
- Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | - Geng Tian
- Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | - Daniel Finley
- Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
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15
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Ishii K, Zhou M, Uchiyama S. Native mass spectrometry for understanding dynamic protein complex. Biochim Biophys Acta Gen Subj 2017; 1862:275-286. [PMID: 28965879 DOI: 10.1016/j.bbagen.2017.09.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 09/17/2017] [Accepted: 09/19/2017] [Indexed: 12/13/2022]
Abstract
Biomolecules have evolved to perform specific and sophisticated activities in a highly coordinated manner organizing into multi-component complexes consisting of proteins, nucleic acids, cofactors or ligands. Understanding such complexes represents a task in earnest for modern bioscience. Traditional structural techniques when extrapolating to macromolecules of ever increasing sizes are confronted with limitations posed by the difficulty in enrichment, solubility, stability as well as lack of homogeneity of these complexes. Alternative approaches are therefore prompted to bridge the gap, one of which is native mass spectrometry. Here we demonstrate the strength of native mass spectrometry, used alone or in combination with other biophysical methods such as analytical ultracentrifugation, small-angle neutron scattering, and small-angle X-ray scattering etc., in addressing dynamic aspects of protein complexes including structural reorganization, subunit exchange, as well as the assembly/disassembly processes in solution that are dictated by transient non-covalent interactions. We review recent studies from our laboratories and others applying native mass spectrometry to both soluble and membrane-embedded assemblies. This article is part of a Special Issue entitled "Biophysical Exploration of Dynamical Ordering of Biomolecular Systems" edited by Dr. Koichi Kato.
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Affiliation(s)
- Kentaro Ishii
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Min Zhou
- Institute of Bio-analytical Chemistry, School of Chemical Engineering, Nanjing University of Science and Technology, No. 200 Xiaolingwei Street, Nanjing 210094, China.
| | - Susumu Uchiyama
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan; Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
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16
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Gu ZC, Wu E, Sailer C, Jando J, Styles E, Eisenkolb I, Kuschel M, Bitschar K, Wang X, Huang L, Vissa A, Yip CM, Yedidi RS, Friesen H, Enenkel C. Ubiquitin orchestrates proteasome dynamics between proliferation and quiescence in yeast. Mol Biol Cell 2017; 28:2479-2491. [PMID: 28768827 PMCID: PMC5597321 DOI: 10.1091/mbc.e17-03-0162] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 06/16/2017] [Accepted: 07/24/2017] [Indexed: 12/14/2022] Open
Abstract
Proteasomes are key protease complexes responsible for protein degradation, and their localization changes with the growth conditions. This work in yeast shows that proteasomes exit the nucleus with the transition from proliferation to quiescence. Ubiquitin is a key player in proteasome dynamics and cytoplasmic proteasome granule formation. Proteasomes are essential for protein degradation in proliferating cells. Little is known about proteasome functions in quiescent cells. In nondividing yeast, a eukaryotic model of quiescence, proteasomes are depleted from the nucleus and accumulate in motile cytosolic granules termed proteasome storage granules (PSGs). PSGs enhance resistance to genotoxic stress and confer fitness during aging. Upon exit from quiescence PSGs dissolve, and proteasomes are rapidly delivered into the nucleus. To identify key players in PSG organization, we performed high-throughput imaging of green fluorescent protein (GFP)-labeled proteasomes in the yeast null-mutant collection. Mutants with reduced levels of ubiquitin are impaired in PSG formation. Colocalization studies of PSGs with proteins of the yeast GFP collection, mass spectrometry, and direct stochastic optical reconstitution microscopy of cross-linked PSGs revealed that PSGs are densely packed with proteasomes and contain ubiquitin but no polyubiquitin chains. Our results provide insight into proteasome dynamics between proliferating and quiescent yeast in response to cellular requirements for ubiquitin-dependent degradation.
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Affiliation(s)
- Zhu Chao Gu
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Edwin Wu
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Carolin Sailer
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Julia Jando
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Erin Styles
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Ina Eisenkolb
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Maike Kuschel
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Katharina Bitschar
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Xiaorong Wang
- Department of Physics and Biophysics, University of California, Irvine, Irvine, CA 92697
| | - Lan Huang
- Department of Physics and Biophysics, University of California, Irvine, Irvine, CA 92697
| | - Adriano Vissa
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Christopher M Yip
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada.,Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Ravikiran S Yedidi
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Helena Friesen
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Cordula Enenkel
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
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17
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Howell LA, Tomko RJ, Kusmierczyk AR. Putting it all together: intrinsic and extrinsic mechanisms governing proteasome biogenesis. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/s11515-017-1439-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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18
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Nucleotide-dependent switch in proteasome assembly mediated by the Nas6 chaperone. Proc Natl Acad Sci U S A 2017; 114:1548-1553. [PMID: 28137839 DOI: 10.1073/pnas.1612922114] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The proteasome is assembled via the nine-subunit lid, nine-subunit base, and 28-subunit core particle (CP). Previous work has shown that the chaperones Rpn14, Nas6, Hsm3, and Nas2 each bind a specific ATPase subunit of the base and antagonize base-CP interaction. Here, we show that the Nas6 chaperone also obstructs base-lid association. Nas6 alternates between these two inhibitory modes according to the nucleotide state of the base. When ATP cannot be hydrolyzed, Nas6 interferes with base-lid, but not base-CP, association. In contrast, under conditions of ATP hydrolysis, Nas6 obstructs base-CP, but not base-lid, association. Modeling of Nas6 into cryoelectron microscopy structures of the proteasome suggests that Nas6 controls both base-lid affinity and base-CP affinity through steric hindrance; Nas6 clashes with the lid in the ATP-hydrolysis-blocked proteasome, but clashes instead with the CP in the ATP-hydrolysis-competent proteasome. Thus, Nas6 provides a dual mechanism to control assembly at both major interfaces of the proteasome.
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19
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High-fidelity mass analysis unveils heterogeneity in intact ribosomal particles. Nat Methods 2017; 14:283-286. [PMID: 28114288 DOI: 10.1038/nmeth.4147] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 12/02/2016] [Indexed: 12/22/2022]
Abstract
Investigation of the structure, assembly and function of protein-nucleic acid macromolecular machines requires multidimensional molecular and structural biology approaches. We describe modifications to an Orbitrap mass spectrometer, enabling high-resolution native MS analysis of 0.8- to 2.3-MDa prokaryotic 30S, 50S and 70S ribosome particles and the 9-MDa Flock House virus. The instrument's improved mass range and sensitivity readily exposes unexpected binding of the ribosome-associated protein SRA.
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20
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Marshall RS, Gemperline DC, Vierstra RD. Purification of 26S Proteasomes and Their Subcomplexes from Plants. Methods Mol Biol 2017; 1511:301-334. [PMID: 27730621 DOI: 10.1007/978-1-4939-6533-5_24] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The 26S proteasome is a highly dynamic, multisubunit, ATP-dependent protease that plays a central role in cellular housekeeping and many aspects of plant growth and development by degrading aberrant polypeptides and key cellular regulators that are first modified by ubiquitin. Although the 26S proteasome was originally enriched from plants over 30 years ago, only recently have significant advances been made in our ability to isolate and study the plant particle. Here, we describe two robust methods for purifying the 26S proteasome and its subcomplexes from Arabidopsis thaliana; one that involves conventional chromatography techniques to isolate the complex from wild-type plants, and another that employs the genetic replacement of individual subunits with epitope-tagged variants combined with affinity purification. In addition to these purification protocols, we describe methods commonly used to analyze the activity and composition of the complex.
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Affiliation(s)
- Richard S Marshall
- Department of Genetics, University of Wisconsin-Madison, 425-G Henry Mall, Madison, WI, USA.,Department of Biology, Washington University in St Louis, Campus Box 1137, One Brookings Drive, St. Louis, MO, 63130, USA
| | - David C Gemperline
- Department of Genetics, University of Wisconsin-Madison, 425-G Henry Mall, Madison, WI, USA
| | - Richard D Vierstra
- Department of Genetics, University of Wisconsin-Madison, 425-G Henry Mall, Madison, WI, USA. .,Department of Biology, Washington University in St Louis, Campus Box 1137, One Brookings Drive, St. Louis, MO, 63130, USA.
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21
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Abstract
Protein complexes form the critical foundation for a wide range of biological process, however understanding the intricate details of their activities is often challenging. In this review we describe how mass spectrometry plays a key role in the analysis of protein assemblies and the cellular pathways which they are involved in. Specifically, we discuss how the versatility of mass spectrometric approaches provides unprecedented information on multiple levels. We demonstrate this on the ubiquitin-proteasome proteolytic pathway, a process that is responsible for protein turnover. We follow the various steps of this degradation route and illustrate the different mass spectrometry workflows that were applied for elucidating molecular information. Overall, this review aims to stimulate the integrated use of multiple mass spectrometry approaches for analyzing complex biological systems.
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22
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Olinares PDB, Dunn AD, Padovan JC, Fernandez-Martinez J, Rout MP, Chait BT. A Robust Workflow for Native Mass Spectrometric Analysis of Affinity-Isolated Endogenous Protein Assemblies. Anal Chem 2016; 88:2799-807. [PMID: 26849307 PMCID: PMC4790104 DOI: 10.1021/acs.analchem.5b04477] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The central players in most cellular events are assemblies of macromolecules. Structural and functional characterization of these assemblies requires knowledge of their subunit stoichiometry and intersubunit connectivity. One of the most direct means for acquiring such information is so-called "native mass spectrometry (MS)", wherein the masses of the intact assemblies and parts thereof are accurately determined. It is of particular interest to apply native MS to the study of endogenous protein assemblies-i.e., those wherein the component proteins are expressed at endogenous levels in their natural functional states, rather than the overexpressed (sometimes partial) constructs commonly employed in classical structural studies, whose assembly can introduce stoichiometry artifacts and other unwanted effects. To date, the application of native MS to the elucidation of endogenous protein complexes has been limited by the difficulty in obtaining pristine cell-derived assemblies at sufficiently high concentrations for effective analysis. Here, to address this challenge, we present a robust workflow that couples rapid and efficient affinity isolation of endogenous protein complexes with a sensitive native MS readout. The resulting workflow has the potential to provide a wealth of data on the stoichiometry and intersubunit connectivity of endogenous protein assemblies-information that is key to successful integrative structural elucidation of biological systems.
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Affiliation(s)
- Paul Dominic B. Olinares
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY 10065 USA
| | - Amelia D. Dunn
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY 10065 USA
| | - Júlio C. Padovan
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY 10065 USA
| | | | - Michael P. Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065 USA
| | - Brian T. Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY 10065 USA
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23
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Wang L, Delahunty C, Fritz-Wolf K, Rahlfs S, Helena Prieto J, Yates JR, Becker K. Characterization of the 26S proteasome network in Plasmodium falciparum. Sci Rep 2015; 5:17818. [PMID: 26639022 PMCID: PMC4671066 DOI: 10.1038/srep17818] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 11/06/2015] [Indexed: 11/09/2022] Open
Abstract
In eukaryotic cells, the ubiquitin-proteasome system as a key regulator of protein quality control is an excellent drug target. We therefore aimed to analyze the 26S proteasome complex in the malaria parasite Plasmodium falciparum, which still threatens almost half of the world’s population. First, we established an affinity purification protocol allowing for the isolation of functional 26S proteasome complexes from the parasite. Subunit composition of the proteasome and component stoichiometry were studied and physiologic interacting partners were identified via in situ protein crosslinking. Furthermore, intrinsic ubiquitin receptors of the plasmodial proteasome were determined and their roles in proteasomal substrate recognition were analyzed. Notably, PfUSP14 was characterized as a proteasome-associated deubiquitinase resulting in the concept that targeting proteasomal deubiquitinating activity in P. falciparum may represent a promising antimalarial strategy. The data provide insights into a profound network orchestrated by the plasmodial proteasome and identified novel drug target candidates in the ubiquitin-proteasome system.
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Affiliation(s)
- Lihui Wang
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Giessen, Germany
| | - Claire Delahunty
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California
| | | | - Stefan Rahlfs
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Giessen, Germany
| | - Judith Helena Prieto
- Department of Chemistry, Western Connecticut State University, Danbury, Connecticut
| | - John R Yates
- Max-Planck Institute for Medical Research, Heidelberg, Germany
| | - Katja Becker
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Giessen, Germany
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24
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Structural characterization of the interaction of Ubp6 with the 26S proteasome. Proc Natl Acad Sci U S A 2015; 112:8626-31. [PMID: 26130806 DOI: 10.1073/pnas.1510449112] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In eukaryotic cells, the 26S proteasome is responsible for the regulated degradation of intracellular proteins. Several cofactors interact transiently with this large macromolecular machine and modulate its function. The deubiquitylating enzyme ubiquitin C-terminal hydrolase 6 [Ubp6; ubiquitin-specific protease (USP) 14 in mammals] is the most abundant proteasome-interacting protein and has multiple roles in regulating proteasome function. Here, we investigate the structural basis of the interaction between Ubp6 and the 26S proteasome in the presence and absence of the inhibitor ubiquitin aldehyde. To this end we have used single-particle electron cryomicroscopy in combination with cross-linking and mass spectrometry. Ubp6 binds to the regulatory particle non-ATPase (Rpn) 1 via its N-terminal ubiquitin-like domain, whereas its catalytic USP domain is positioned variably. Addition of ubiquitin aldehyde stabilizes the binding of the USP domain in a position where it bridges the proteasome subunits Rpn1 and the regulatory particle triple-A ATPase (Rpt) 1. The USP domain binds to Rpt1 in the immediate vicinity of the Ubp6 active site, which may effect its activation. The catalytic triad is positioned in proximity to the mouth of the ATPase module and to the deubiquitylating enzyme Rpn11, strongly implying their functional linkage. On the proteasome side, binding of Ubp6 favors conformational switching of the 26S proteasome into an intermediate-energy conformational state, in particular upon the addition of ubiquitin aldehyde. This modulation of the conformational space of the 26S proteasome by Ubp6 explains the effects of Ubp6 on the kinetics of proteasomal degradation.
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25
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Going CC, Williams ER. Supercharging with m-Nitrobenzyl Alcohol and Propylene Carbonate: Forming Highly Charged Ions with Extended, Near-Linear Conformations. Anal Chem 2015; 87:3973-80. [DOI: 10.1021/acs.analchem.5b00071] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Catherine C. Going
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
| | - Evan R. Williams
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
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26
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Proteasome stress responses in Schistosoma mansoni. Parasitol Res 2015; 114:1747-60. [DOI: 10.1007/s00436-015-4360-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Accepted: 01/30/2015] [Indexed: 12/19/2022]
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27
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Abstract
It has long been appreciated that aneuploidy – in which cells possess a karyotype that is not a multiple of the haploid complement – has a substantial impact on human health, but its effects at the subcellular level have only recently become a focus of investigation. Here, we summarize new findings characterizing the impact of aneuploidy on protein quality control. Because aneuploidy has been associated with many diseases, foremost among them being cancer, and has also been linked to aging, we also offer our perspective on whether and how the effects of aneuploidy on protein quality control could contribute to these conditions. We argue that acquiring a deeper understanding of the relationship between aneuploidy, disease and aging could lead to the development of new anti-cancer and anti-aging treatments.
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Affiliation(s)
- Ana B Oromendia
- David H. Koch Institute for Integrative Cancer Research, Department of Biology and Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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28
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Fabre B, Lambour T, Garrigues L, Ducoux-Petit M, Amalric F, Monsarrat B, Burlet-Schiltz O, Bousquet-Dubouch MP. Label-Free Quantitative Proteomics Reveals the Dynamics of Proteasome Complexes Composition and Stoichiometry in a Wide Range of Human Cell Lines. J Proteome Res 2014; 13:3027-37. [DOI: 10.1021/pr500193k] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Bertrand Fabre
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale); 205 route de Narbonne, F-31077 Toulouse, France
- Université de Toulouse; UPS; IPBS; F-31077 Toulouse, France
| | - Thomas Lambour
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale); 205 route de Narbonne, F-31077 Toulouse, France
- Université de Toulouse; UPS; IPBS; F-31077 Toulouse, France
| | - Luc Garrigues
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale); 205 route de Narbonne, F-31077 Toulouse, France
- Université de Toulouse; UPS; IPBS; F-31077 Toulouse, France
| | - Manuelle Ducoux-Petit
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale); 205 route de Narbonne, F-31077 Toulouse, France
- Université de Toulouse; UPS; IPBS; F-31077 Toulouse, France
| | - François Amalric
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale); 205 route de Narbonne, F-31077 Toulouse, France
- Université de Toulouse; UPS; IPBS; F-31077 Toulouse, France
| | - Bernard Monsarrat
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale); 205 route de Narbonne, F-31077 Toulouse, France
- Université de Toulouse; UPS; IPBS; F-31077 Toulouse, France
| | - Odile Burlet-Schiltz
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale); 205 route de Narbonne, F-31077 Toulouse, France
- Université de Toulouse; UPS; IPBS; F-31077 Toulouse, France
| | - Marie-Pierre Bousquet-Dubouch
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale); 205 route de Narbonne, F-31077 Toulouse, France
- Université de Toulouse; UPS; IPBS; F-31077 Toulouse, France
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29
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Politis A, Stengel F, Hall Z, Hernández H, Leitner A, Walzthoeni T, Robinson CV, Aebersold R. A mass spectrometry-based hybrid method for structural modeling of protein complexes. Nat Methods 2014; 11:403-406. [PMID: 24509631 PMCID: PMC3972104 DOI: 10.1038/nmeth.2841] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 12/12/2013] [Indexed: 01/22/2023]
Abstract
We describe a method that integrates data derived from different mass spectrometry (MS)-based techniques with a modeling strategy for structural characterization of protein assemblies. We encoded structural data derived from native MS, bottom-up proteomics, ion mobility-MS and chemical cross-linking MS into modeling restraints to compute the most likely structure of a protein assembly. We used the method to generate near-native models for three known structures and characterized an assembly intermediate of the proteasomal base.
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Affiliation(s)
- Argyris Politis
- Department of Chemistry, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Florian Stengel
- Department of Biology, Institute of Molecular Systems Biology, Eidgenossische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Zoe Hall
- Department of Chemistry, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Helena Hernández
- Department of Chemistry, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Alexander Leitner
- Department of Biology, Institute of Molecular Systems Biology, Eidgenossische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Thomas Walzthoeni
- Department of Biology, Institute of Molecular Systems Biology, Eidgenossische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Carol V. Robinson
- Department of Chemistry, University of Oxford, South Parks Road, Oxford, United Kingdom
| | - Ruedi Aebersold
- Department of Biology, Institute of Molecular Systems Biology, Eidgenossische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
- Faculty of Science, University of Zurich, Zurich, Switzerland
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30
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Satoh T, Saeki Y, Hiromoto T, Wang YH, Uekusa Y, Yagi H, Yoshihara H, Yagi-Utsumi M, Mizushima T, Tanaka K, Kato K. Structural basis for proteasome formation controlled by an assembly chaperone nas2. Structure 2014; 22:731-43. [PMID: 24685148 DOI: 10.1016/j.str.2014.02.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 01/30/2014] [Accepted: 02/21/2014] [Indexed: 11/18/2022]
Abstract
Proteasome formation does not occur due to spontaneous self-organization but results from a highly ordered process assisted by several assembly chaperones. The assembly of the proteasome ATPase subunits is assisted by four client-specific chaperones, of which three have been structurally resolved. Here, we provide the structural basis for the working mechanisms of the last, hereto structurally uncharacterized assembly chaperone, Nas2. We revealed that Nas2 binds to the Rpt5 subunit in a bivalent mode: the N-terminal helical domain of Nas2 masks the Rpt1-interacting surface of Rpt5, whereas its C-terminal PDZ domain caps the C-terminal proteasome-activating motif. Thus, Nas2 operates as a proteasome activation blocker, offering a checkpoint during the formation of the 19S ATPase prior to its docking onto the proteolytic 20S core particle.
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Affiliation(s)
- Tadashi Satoh
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan; JST, PRESTO, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
| | - Yasushi Saeki
- Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Takeshi Hiromoto
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
| | - Ying-Hui Wang
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan; Okazaki Institute for Integrative Bioscience and Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Yoshinori Uekusa
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan; Okazaki Institute for Integrative Bioscience and Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Hirokazu Yagi
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
| | - Hidehito Yoshihara
- Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Maho Yagi-Utsumi
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan; Okazaki Institute for Integrative Bioscience and Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Tsunehiro Mizushima
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan; Picobiology Institute, Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Keiji Tanaka
- Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Koichi Kato
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan; Okazaki Institute for Integrative Bioscience and Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan.
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31
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Sahara K, Kogleck L, Yashiroda H, Murata S. The mechanism for molecular assembly of the proteasome. Adv Biol Regul 2014; 54:51-8. [PMID: 24145026 DOI: 10.1016/j.jbior.2013.09.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 09/09/2013] [Indexed: 05/23/2023]
Abstract
In eukaryotic cells, the ubiquitin proteasome system plays important roles in diverse cellular processes. The 26S proteasome is a large enzyme complex that degrades ubiquitinated proteins. It consists of 33 different subunits that form two subcomplexes, the 20S core particle and the 19S regulatory particle. Recently, several chaperones dedicated to the accurate assembly of this protease complex have been identified, but the complete mechanism of the 26S proteasome assembly is still unclear. In this review, we summarize what is known about the assembly of proteasome to date and present our group's recent findings on the role of the GET pathway in the assembly of the 26S proteasome, in addition to its role in mediating the insertion of tail-anchored (TA) proteins into the ER membrane.
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Affiliation(s)
- Kazutaka Sahara
- Laboratory of Protein Metabolism, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Larissa Kogleck
- Laboratory of Protein Metabolism, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Hideki Yashiroda
- Laboratory of Protein Metabolism, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Shigeo Murata
- Laboratory of Protein Metabolism, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan.
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Mass Spectrometric Analysis of Post-translational Modifications (PTMs) and Protein–Protein Interactions (PPIs). ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 806:205-35. [DOI: 10.1007/978-3-319-06068-2_9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Ngounou Wetie AG, Sokolowska I, Woods AG, Roy U, Deinhardt K, Darie CC. Protein-protein interactions: switch from classical methods to proteomics and bioinformatics-based approaches. Cell Mol Life Sci 2014; 71:205-28. [PMID: 23579629 PMCID: PMC11113707 DOI: 10.1007/s00018-013-1333-1] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Revised: 03/25/2013] [Accepted: 03/26/2013] [Indexed: 11/28/2022]
Abstract
Following the sequencing of the human genome and many other organisms, research on protein-coding genes and their functions (functional genomics) has intensified. Subsequently, with the observation that proteins are indeed the molecular effectors of most cellular processes, the discipline of proteomics was born. Clearly, proteins do not function as single entities but rather as a dynamic network of team players that have to communicate. Though genetic (yeast two-hybrid Y2H) and biochemical methods (co-immunoprecipitation Co-IP, affinity purification AP) were the methods of choice at the beginning of the study of protein-protein interactions (PPI), in more recent years there has been a shift towards proteomics-based methods and bioinformatics-based approaches. In this review, we first describe in depth PPIs and we make a strong case as to why unraveling the interactome is the next challenge in the field of proteomics. Furthermore, classical methods of investigation of PPIs and structure-based bioinformatics approaches are presented. The greatest emphasis is placed on proteomic methods, especially native techniques that were recently developed and that have been shown to be reliable. Finally, we point out the limitations of these methods and the need to set up a standard for the validation of PPI experiments.
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Affiliation(s)
- Armand G. Ngounou Wetie
- Department of Chemistry and Biomolecular Science, Biochemistry and Proteomics Group, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699-5810 USA
| | - Izabela Sokolowska
- Department of Chemistry and Biomolecular Science, Biochemistry and Proteomics Group, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699-5810 USA
| | - Alisa G. Woods
- Department of Chemistry and Biomolecular Science, Biochemistry and Proteomics Group, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699-5810 USA
| | - Urmi Roy
- Department of Chemistry and Biomolecular Science, Biochemistry and Proteomics Group, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699-5810 USA
| | - Katrin Deinhardt
- Centre for Biological Sciences, University of Southampton, Life Sciences Building 85, Southampton, SO17 1BJ UK
- Institute for Life Sciences, University of Southampton, Life Sciences Building 85, Southampton, SO17 1BJ UK
| | - Costel C. Darie
- Department of Chemistry and Biomolecular Science, Biochemistry and Proteomics Group, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699-5810 USA
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Abstract
The proteasome is a sophisticated, 2.5-MDa, multisubunit complex that contains a catalytic core particle (CP) and two terminal regulatory particles (RPs); the RPs associate with the termini of the central CP at opposite orientations. The CP consists of four axially stacked heptameric rings (two outer α-rings and two inner β-rings), which are made up of seven structurally related, but not identical, α and β subunits. The CP contains catalytic threonine residues (in β1, β2, and β5 with caspase-like, trypsin-like, and chymotrypsin-like activities, respectively) on the surface of the chamber formed by two abutting β-rings. The RP recognizes polyubiquitylated substrate proteins and unfolds and translocates these proteins to the interior of the CP for degradation. The RP comprises 19 different subunits, which are thought to form two subcomplexes called the lid and the base. One longstanding question is how the complex structure of the proteasome is organized with high fidelity. Recently, we proposed a novel assembly mechanism that is assisted by multiple proteasome-dedicated chaperones. In addition, we discovered two immuno-type proteasomes, the immunoproteasome and the thymoproteasome, whose catalytic subunits are replaced by homologous counterparts. These two isoforms perform specialized functions that help discriminate self from non-self in cell-mediated immunity (i.e., they function as enzymes that process intracellular antigens for cytotoxic T lymphocyte responses and thymic positive selection). Moreover, emerging evidence suggests that the proteasome is crucially involved in the pathophysiology of various intractable diseases that are increasing in today's aging society.
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Förster F, Unverdorben P, Śledź P, Baumeister W. Unveiling the Long-Held Secrets of the 26S Proteasome. Structure 2013; 21:1551-62. [DOI: 10.1016/j.str.2013.08.010] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 08/15/2013] [Accepted: 08/16/2013] [Indexed: 01/23/2023]
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Ehlinger A, Walters KJ. Structural insights into proteasome activation by the 19S regulatory particle. Biochemistry 2013; 52:3618-28. [PMID: 23672618 DOI: 10.1021/bi400417a] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Since its discovery in the late 1970s, the ubiquitin-proteasome system (UPS) has become recognized as the major pathway for regulated cellular proteolysis. Processes such as cell cycle control, pathogen resistance, and protein quality control rely on selective protein degradation at the proteasome for homeostatic function. Perhaps as a consequence of the importance of this pathway, and the genesis of severe diseases upon its dysregulation, protein degradation by the UPS is highly controlled from the level of substrate recognition to proteolysis. Technological advances over the past decade have created an explosion of structural and mechanistic information that has underscored the complexity of the proteasome and its upstream regulatory factors. Significant insights have come from the study of the 19S proteasome regulatory particle (RP) responsible for recognition and processing of ubiquitinated substrates destined for proteolysis. Established as a highly dynamic proteasome activator, the RP has a large number of both permanent and transient components with specialized functional roles that are critical for proteasome function. In this review, we highlight recent mechanistic developments in the study of proteasome activation by the RP and how they provide context to our current understanding of the UPS.
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Affiliation(s)
- Aaron Ehlinger
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota , Minneapolis, Minnesota 55455, United States
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Bohn S, Sakata E, Beck F, Pathare GR, Schnitger J, Nágy I, Baumeister W, Förster F. Localization of the regulatory particle subunit Sem1 in the 26S proteasome. Biochem Biophys Res Commun 2013; 435:250-4. [PMID: 23643786 DOI: 10.1016/j.bbrc.2013.04.069] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 04/23/2013] [Indexed: 10/26/2022]
Abstract
The ubiquitin-proteasome system is responsible for regulated protein degradation in the cell with the 26S proteasome acting as its executive arm. The molecular architecture of this 2.5 MDa complex has been established recently, with the notable exception of the small acidic subunit Sem1. Here, we localize the C-terminal helix of Sem1 binding to the PCI domain of the subunit Rpn7 using cryo-electron microscopy single particle reconstruction of proteasomes purified from yeast cells with sem1 deletion. The approximate position of the N-terminal region of Sem1 bridging the cleft between Rpn7 and Rpn3 was inferred based on site-specific cross-linking data of the 26S proteasome. Our structural studies indicate that Sem1 can assume different conformations in different contexts, which supports the idea that Sem1 functions as a molecular glue stabilizing the Rpn3/Rpn7 heterodimer.
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Affiliation(s)
- Stefan Bohn
- Max-Planck Institute of Biochemistry, Department of Molecular Structural Biology, D-82152 Martinsried, Germany
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Śledź P, Unverdorben P, Beck F, Pfeifer G, Schweitzer A, Förster F, Baumeister W. Structure of the 26S proteasome with ATP-γS bound provides insights into the mechanism of nucleotide-dependent substrate translocation. Proc Natl Acad Sci U S A 2013; 110:7264-9. [PMID: 23589842 PMCID: PMC3645540 DOI: 10.1073/pnas.1305782110] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The 26S proteasome is a 2.5-MDa, ATP-dependent multisubunit proteolytic complex that processively destroys proteins carrying a degradation signal. The proteasomal ATPase heterohexamer is a key module of the 19S regulatory particle; it unfolds substrates and translocates them into the 20S core particle where degradation takes place. We used cryoelectron microscopy single-particle analysis to obtain insights into the structural changes of 26S proteasome upon the binding and hydrolysis of ATP. The ATPase ring adopts at least two distinct helical staircase conformations dependent on the nucleotide state. The transition from the conformation observed in the presence of ATP to the predominant conformation in the presence of ATP-γS induces a sliding motion of the ATPase ring over the 20S core particle ring leading to an alignment of the translocation channels of the ATPase and the core particle gate, a conformational state likely to facilitate substrate translocation. Two types of intersubunit modules formed by the large ATPase domain of one ATPase subunit and the small ATPase domain of its neighbor exist. They resemble the contacts observed in the crystal structures of ClpX and proteasome-activating nucleotidase, respectively. The ClpX-like contacts are positioned consecutively and give rise to helical shape in the hexamer, whereas the proteasome-activating nucleotidase-like contact is required to close the ring. Conformational switching between these forms allows adopting different helical conformations in different nucleotide states. We postulate that ATP hydrolysis by the regulatory particle ATPase (Rpt) 5 subunit initiates a cascade of conformational changes, leading to pulling of the substrate, which is primarily executed by Rpt1, Rpt2, and Rpt6.
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Affiliation(s)
- Paweł Śledź
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Pia Unverdorben
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Florian Beck
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Günter Pfeifer
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Andreas Schweitzer
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Friedrich Förster
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Wolfgang Baumeister
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
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Walzthoeni T, Leitner A, Stengel F, Aebersold R. Mass spectrometry supported determination of protein complex structure. Curr Opin Struct Biol 2013; 23:252-60. [PMID: 23522702 DOI: 10.1016/j.sbi.2013.02.008] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 01/17/2013] [Accepted: 02/26/2013] [Indexed: 12/23/2022]
Abstract
Virtually all the biological processes are controlled and catalyzed by proteins which are, in many cases, in complexes with other proteins. Therefore, understanding the architecture and structure of protein complexes is critical to understanding their biological role and function. Traditionally, high-resolution data for structural analysis of proteins or protein complexes have been generated by the powerful methods of X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy. More recently, mass spectrometry (MS)-based methods have been developed that provide low-resolution structural information, which contributes to the determination of the native structure of protein complexes that have remained refractory to the high-resolution methods. Native MS and affinity purification coupled with MS (AP-MS) have been used to characterize the composition, stoichiometry and connectivity of protein complexes. Chemical cross-linking MS (CX-MS) provides protein-protein interaction data supplemented with distance information that indicates residues that are in close spatial proximity in the native protein structure. Hydrogen-deuterium exchange combined with MS has been used to map protein-protein binding sites. Here, we focus on recent developments in CX-MS and native MS and their application to challenging problems in structural biology.
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Affiliation(s)
- Thomas Walzthoeni
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Wolfgang-Pauli-Str. 16, 8093 Zurich, Switzerland
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Chondrogianni N, Petropoulos I, Grimm S, Georgila K, Catalgol B, Friguet B, Grune T, Gonos ES. Protein damage, repair and proteolysis. Mol Aspects Med 2012; 35:1-71. [PMID: 23107776 DOI: 10.1016/j.mam.2012.09.001] [Citation(s) in RCA: 160] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 09/26/2012] [Indexed: 01/10/2023]
Abstract
Proteins are continuously affected by various intrinsic and extrinsic factors. Damaged proteins influence several intracellular pathways and result in different disorders and diseases. Aggregation of damaged proteins depends on the balance between their generation and their reversal or elimination by protein repair systems and degradation, respectively. With regard to protein repair, only few repair mechanisms have been evidenced including the reduction of methionine sulfoxide residues by the methionine sulfoxide reductases, the conversion of isoaspartyl residues to L-aspartate by L-isoaspartate methyl transferase and deglycation by phosphorylation of protein-bound fructosamine by fructosamine-3-kinase. Protein degradation is orchestrated by two major proteolytic systems, namely the lysosome and the proteasome. Alteration of the function for both systems has been involved in all aspects of cellular metabolic networks linked to either normal or pathological processes. Given the importance of protein repair and degradation, great effort has recently been made regarding the modulation of these systems in various physiological conditions such as aging, as well as in diseases. Genetic modulation has produced promising results in the area of protein repair enzymes but there are not yet any identified potent inhibitors, and, to our knowledge, only one activating compound has been reported so far. In contrast, different drugs as well as natural compounds that interfere with proteolysis have been identified and/or developed resulting in homeostatic maintenance and/or the delay of disease progression.
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Affiliation(s)
- Niki Chondrogianni
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Helenic Research Foundation, 48 Vas. Constantinou Ave., 116 35 Athens, Greece.
| | - Isabelle Petropoulos
- Laboratoire de Biologie Cellulaire du Vieillissement, UR4-UPMC, IFR 83, Université Pierre et Marie Curie-Paris 6, 4 Place Jussieu, 75005 Paris, France
| | - Stefanie Grimm
- Department of Nutritional Toxicology, Institute of Nutrition, Friedrich-Schiller University, Dornburger Straße 24, 07743 Jena, Germany
| | - Konstantina Georgila
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Helenic Research Foundation, 48 Vas. Constantinou Ave., 116 35 Athens, Greece
| | - Betul Catalgol
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research Center (GEMHAM), Marmara University, Haydarpasa, Istanbul, Turkey
| | - Bertrand Friguet
- Laboratoire de Biologie Cellulaire du Vieillissement, UR4-UPMC, IFR 83, Université Pierre et Marie Curie-Paris 6, 4 Place Jussieu, 75005 Paris, France
| | - Tilman Grune
- Department of Nutritional Toxicology, Institute of Nutrition, Friedrich-Schiller University, Dornburger Straße 24, 07743 Jena, Germany
| | - Efstathios S Gonos
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Helenic Research Foundation, 48 Vas. Constantinou Ave., 116 35 Athens, Greece.
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Barrera NP, Zhou M, Robinson CV. The role of lipids in defining membrane protein interactions: insights from mass spectrometry. Trends Cell Biol 2012; 23:1-8. [PMID: 22980035 DOI: 10.1016/j.tcb.2012.08.007] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 08/14/2012] [Accepted: 08/14/2012] [Indexed: 12/19/2022]
Abstract
Cellular membranes comprise hundreds of lipids in which protein complexes, such as ion channels, receptors, and scaffolding complexes, are embedded. These protein assemblies act as signalling and trafficking platforms for processes fundamental to life. Much effort in recent years has focused on identifying the protein components of these complexes after their extraction from the lipid membrane in detergent micelles. Spectacular advances have been made using X-ray crystallography, providing in some cases detailed information about the mechanism of pumping and channel gating. These structural studies are leading to a growing realisation that, to understand their function, it is not only the structures of the protein components that are important but also knowledge of the protein-lipid interactions. This review highlights recent insights gained from this knowledge, surveys methods being developed for probing these interactions, and focuses specifically on the potential of mass spectrometry in this growing area of research.
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Affiliation(s)
- Nelson P Barrera
- Department of Physiology, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile.
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Abstract
The 26S proteasome operates at the executive end of the ubiquitin-proteasome pathway. Here, we present a cryo-EM structure of the Saccharomyces cerevisiae 26S proteasome at a resolution of 7.4 Å or 6.7 Å (Fourier-Shell Correlation of 0.5 or 0.3, respectively). We used this map in conjunction with molecular dynamics-based flexible fitting to build a near-atomic resolution model of the holocomplex. The quality of the map allowed us to assign α-helices, the predominant secondary structure element of the regulatory particle subunits, throughout the entire map. We were able to determine the architecture of the Rpn8/Rpn11 heterodimer, which had hitherto remained elusive. The MPN domain of Rpn11 is positioned directly above the AAA-ATPase N-ring suggesting that Rpn11 deubiquitylates substrates immediately following commitment and prior to their unfolding by the AAA-ATPase module. The MPN domain of Rpn11 dimerizes with that of Rpn8 and the C-termini of both subunits form long helices, which are integral parts of a coiled-coil module. Together with the C-terminal helices of the six PCI-domain subunits they form a very large coiled-coil bundle, which appears to serve as a flexible anchoring device for all the lid subunits.
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Abstract
An abundant class of E3 ubiquitin ligases encodes the RING-finger domain. The RING finger binds to the E2 ubiquitin-conjugating enzyme and brings together both the E2 and substrate. It is predicted that 477 RING finger E3 ligases exist in Arabidopsis thaliana. A particular family among them, named Arabidopsis Tóxicos en Levadura (ATL), consists of 91 members that contain the RING-H2 variation and a hydrophobic domain located at the N-terminal end. Transmembrane E3 ligases are important in several biological processes. For instance, some transmembrane RING finger E3 ligases are main participants in the endoplasmic reticulum-associated degradation pathway that targets misfolded proteins. Functional analysis of a number of ATLs has shown that some of them regulate distinct pathways in plants. Several ATLs have been shown to participate in defense responses, while others play a role in the regulation of the carbon/nitrogen response during post-germinative seedling growth transition, in the regulation of cell death during root development, in endosperm development, or in the transition to flowering under short day conditions. The ATL family has also been instrumental in evolution studies for showing how gene families are expanded in plant genomes.
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Affiliation(s)
- Plinio Guzmán
- Departamento de Ingeniería Genética de Plantas Centro de Investigación y de Estudios Avanzados, Unidad Irapuato, Irapuato, México.
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Kim S, Nishide A, Saeki Y, Takagi K, Tanaka K, Kato K, Mizushima T. New crystal structure of the proteasome-dedicated chaperone Rpn14 at 1.6 Å resolution. Acta Crystallogr Sect F Struct Biol Cryst Commun 2012; 68:517-21. [PMID: 22691779 PMCID: PMC3374504 DOI: 10.1107/s1744309112011359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 03/15/2012] [Indexed: 11/10/2022]
Abstract
The 26S proteasome is an ATP-dependent protease responsible for selective degradation of polyubiquitylated proteins. Recent studies have suggested that proteasome assembly is a highly ordered multi-step process assisted by specific chaperones. Rpn14, an assembly chaperone for ATPase-ring formation, specifically recognizes the ATPase subunit Rpt6. The structure of Rpn14 at 2.0 Å resolution in space group P6(4) has previously been reported, but the detailed mechanism of Rpn14 function remains unclear. Here, a new crystal structure of Rpn14 with an E384A mutation is presented in space group P2(1) at 1.6 Å resolution. This high-resolution structure provides a framework for understanding proteasome assembly.
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Affiliation(s)
- Sangwoo Kim
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
| | - Akira Nishide
- Picobiology Institute, Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Yasushi Saeki
- Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Kenji Takagi
- Picobiology Institute, Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Keiji Tanaka
- Laboratory of Protein Metabolism, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Koichi Kato
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
- Institute for Molecular Science and Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan
| | - Tsunehiro Mizushima
- Picobiology Institute, Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
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Dual functions of the Hsm3 protein in chaperoning and scaffolding regulatory particle subunits during the proteasome assembly. Proc Natl Acad Sci U S A 2012; 109:E1001-10. [PMID: 22460800 DOI: 10.1073/pnas.1116538109] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The 26S proteasome, a molecular machine responsible for regulated protein degradation, consists of a proteolytic core particle (20S CP) associated with 19S regulatory particles (19S RPs) subdivided into base and lid subcomplexes. The assembly of 19S RP base subcomplex is mediated by multiple dedicated chaperones. Among these, Hsm3 is important for normal growth and directly targets the carboxyl-terminal (C-terminal) domain of Rpt1 of the Rpt1-Rpt2-Rpn1 assembly intermediate. Here, we report crystal structures of the yeast Hsm3 chaperone free and bound to the C-terminal domain of Rpt1. Unexpectedly, the structure of the complex suggests that within the Hsm3-Rpt1-Rpt2 module, Hsm3 also contacts Rpt2. We show that in both yeast and mammals, Hsm3 actually directly binds the AAA domain of Rpt2. The Hsm3 C-terminal region involved in this interaction is required in vivo for base assembly, although it is dispensable for binding Rpt1. Although Rpt1 and Rpt2 exhibit weak affinity for each other, Hsm3 unexpectedly acts as an essential matchmaker for the Rpt1-Rpt2-Rpn1 assembly by bridging both Rpt1 and Rpt2. In addition, we provide structural and biochemical evidence on how Hsm3/S5b may regulate the 19S RP association to the 20S CP proteasome. Our data point out the diverse functions of assembly chaperones.
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Nakamura M, Basavarajaiah P, Rousset E, Beraud C, Latreille D, Henaoui IS, Lassot I, Mari B, Kiernan R. Spt6 levels are modulated by PAAF1 and proteasome to regulate the HIV-1 LTR. Retrovirology 2012; 9:13. [PMID: 22316138 PMCID: PMC3305501 DOI: 10.1186/1742-4690-9-13] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 02/08/2012] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Tat-mediated activation of the HIV-1 promoter depends upon a proteasome-associated factor, PAAF1, which dissociates 26S proteasome to produce 19S RP that is essential for transcriptional elongation. The effect of PAAF1 on proteasome activity could also potentially shield certain factors from proteolysis, which may be implicated in the transcriptional co-activator activity of PAAF1 towards the LTR. RESULTS Here, we show that Spt6 is targeted by proteasome in the absence of PAAF1. PAAF1 interacts with the N-terminus of Spt6, suggesting that PAAF1 protects Spt6 from proteolysis. Depletion of either PAAF1 or Spt6 reduced histone occupancy at the HIV-1 promoter, and induced the synthesis of aberrant transcripts. Ectopic Spt6 expression or treatment with proteasome inhibitor partially rescued the transcription defect associated with loss of PAAF1. Transcriptional profiling followed by ChIP identified a subset of cellular genes that are regulated in a similar fashion to HIV-1 by Spt6 and/or PAAF1, including many that are involved in cancer, such as BRCA1 and BARD1. CONCLUSION These results show that intracellular levels of Spt6 are fine-tuned by PAAF1 and proteasome, which is required for HIV-1 transcription and extends to cellular genes implicated in cancer.
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Affiliation(s)
- Mirai Nakamura
- Laboratoire de Régulation des Gènes, Institut de Génétique Humaine, CNRS UPR1142, Montpellier, France
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47
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Takagi K, Kim S, Yukii H, Ueno M, Morishita R, Endo Y, Kato K, Tanaka K, Saeki Y, Mizushima T. Structural basis for specific recognition of Rpt1p, an ATPase subunit of 26 S proteasome, by proteasome-dedicated chaperone Hsm3p. J Biol Chem 2012; 287:12172-82. [PMID: 22334676 DOI: 10.1074/jbc.m112.345876] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The 26 S proteasome is a 2.5-MDa molecular machine that degrades ubiquitinated proteins in eukaryotic cells. It consists of a proteolytic core particle and two 19 S regulatory particles (RPs) composed of 6 ATPase (Rpt) and 13 non-ATPase (Rpn) subunits. Multiple proteasome-dedicated chaperones facilitate the assembly of the proteasome, but little is known about the detailed mechanisms. Hsm3, a 19 S RP dedicated chaperone, transiently binds to the C-terminal domain of the Rpt1 subunit and forms a tetrameric complex, Hsm3-Rpt1-Rpt2-Rpn1, during maturation of the ATPase ring of 19 S RP. To elucidate the structural basis of Hsm3 function, we determined the crystal structures of Hsm3 and its complex with the C-terminal domain of the Rpt1 subunit (Rpt1C). Hsm3 has a C-shaped structure that consists of 11 HEAT repeats. The structure of the Hsm3-Rpt1C complex revealed that the interacting surface between Hsm3 and Rpt1 is a hydrophobic core and a complementary charged surface. Mutations in the Hsm3-Rpt1 surface resulted in the assembly defect of the 26 S proteasome. Furthermore, a structural model of the Hsm3-Rpt ring complex and an in vitro binding assay suggest that Hsm3 can bind Rpt2 in addition to Rpt1. Collectively, our results provide the structural basis of the molecular functions of Hsm3 for the RP assembly.
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Affiliation(s)
- Kenji Takagi
- Picobiology Institute, Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1, Kouto, Kamigori-cho, Ako-gun, Hyogo, 678-1297, Japan
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Lamond AI, Uhlen M, Horning S, Makarov A, Robinson CV, Serrano L, Hartl FU, Baumeister W, Werenskiold AK, Andersen JS, Vorm O, Linial M, Aebersold R, Mann M. Advancing cell biology through proteomics in space and time (PROSPECTS). Mol Cell Proteomics 2012; 11:O112.017731. [PMID: 22311636 PMCID: PMC3316737 DOI: 10.1074/mcp.o112.017731] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The term “proteomics” encompasses the large-scale detection and analysis of proteins and their post-translational modifications. Driven by major improvements in mass spectrometric instrumentation, methodology, and data analysis, the proteomics field has burgeoned in recent years. It now provides a range of sensitive and quantitative approaches for measuring protein structures and dynamics that promise to revolutionize our understanding of cell biology and molecular mechanisms in both human cells and model organisms. The Proteomics Specification in Time and Space (PROSPECTS) Network is a unique EU-funded project that brings together leading European research groups, spanning from instrumentation to biomedicine, in a collaborative five year initiative to develop new methods and applications for the functional analysis of cellular proteins. This special issue of Molecular and Cellular Proteomics presents 16 research papers reporting major recent progress by the PROSPECTS groups, including improvements to the resolution and sensitivity of the Orbitrap family of mass spectrometers, systematic detection of proteins using highly characterized antibody collections, and new methods for absolute as well as relative quantification of protein levels. Manuscripts in this issue exemplify approaches for performing quantitative measurements of cell proteomes and for studying their dynamic responses to perturbation, both during normal cellular responses and in disease mechanisms. Here we present a perspective on how the proteomics field is moving beyond simply identifying proteins with high sensitivity toward providing a powerful and versatile set of assay systems for characterizing proteome dynamics and thereby creating a new “third generation” proteomics strategy that offers an indispensible tool for cell biology and molecular medicine.
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Affiliation(s)
- Angus I Lamond
- Centre for Gene Regulation & Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH United Kingdom.
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Linking structural change with functional regulation—insights from mass spectrometry. Curr Opin Struct Biol 2012; 22:44-51. [DOI: 10.1016/j.sbi.2011.12.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 12/27/2011] [Indexed: 12/20/2022]
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Localization of the proteasomal ubiquitin receptors Rpn10 and Rpn13 by electron cryomicroscopy. Proc Natl Acad Sci U S A 2012; 109:1479-84. [PMID: 22215586 DOI: 10.1073/pnas.1119394109] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Two canonical subunits of the 26S proteasome, Rpn10 and Rpn13, function as ubiquitin (Ub) receptors. The mutual arrangement of these subunits--and all other non-ATPase subunits--in the regulatory particle is unknown. Using electron cryomicroscopy, we calculated difference maps between wild-type 26S proteasome from Saccharomyces cerevisiae and deletion mutants (rpn10Δ, rpn13Δ, and rpn10Δrpn13Δ). These maps allowed us to localize the two Ub receptors unambiguously. Rpn10 and Rpn13 mapped to the apical part of the 26S proteasome, above the N-terminal coiled coils of the AAA-ATPase heterodimers Rpt4/Rpt5 and Rpt1/Rpt2, respectively. On the basis of the mutual positions of Rpn10 and Rpn13, we propose a model for polyubiquitin binding to the 26S proteasome.
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