1
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Varejão N, Lascorz J, Codina-Fabra J, Bellí G, Borràs-Gas H, Torres-Rosell J, Reverter D. Structural basis for the E3 ligase activity enhancement of yeast Nse2 by SUMO-interacting motifs. Nat Commun 2021; 12:7013. [PMID: 34853311 PMCID: PMC8636563 DOI: 10.1038/s41467-021-27301-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/09/2021] [Indexed: 01/02/2023] Open
Abstract
Post-translational modification of proteins by ubiquitin and ubiquitin-like modifiers, such as SUMO, are key events in protein homeostasis or DNA damage response. Smc5/6 is a nuclear multi-subunit complex that participates in the recombinational DNA repair processes and is required in the maintenance of chromosome integrity. Nse2 is a subunit of the Smc5/6 complex that possesses SUMO E3 ligase activity by the presence of a SP-RING domain that activates the E2~SUMO thioester for discharge on the substrate. Here we present the crystal structure of the SUMO E3 ligase Nse2 in complex with an E2-SUMO thioester mimetic. In addition to the interface between the SP-RING domain and the E2, the complex reveals how two SIM (SUMO-Interacting Motif) -like motifs in Nse2 are restructured upon binding the donor and E2-backside SUMO during the E3-dependent discharge reaction. Both SIM interfaces are essential in the activity of Nse2 and are required to cope with DNA damage. Nse2 is a SUMO E3 ligase component of the Smc5/6 multisubunit complex involved in the DNA repair and chromosome integrity. Here, the structure of the Nse2 in complex with an E2-SUMO thioester mimetic reveals the combined action of two SIM motifs during the E3- dependent conjugation reaction.
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Affiliation(s)
- Nathalia Varejão
- Institut de Biotecnologia i de Biomedicina (IBB) and Dept. de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Jara Lascorz
- Institut de Biotecnologia i de Biomedicina (IBB) and Dept. de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Joan Codina-Fabra
- IRBLLEIDA, Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - Gemma Bellí
- IRBLLEIDA, Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - Helena Borràs-Gas
- Institut de Biotecnologia i de Biomedicina (IBB) and Dept. de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Jordi Torres-Rosell
- IRBLLEIDA, Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - David Reverter
- Institut de Biotecnologia i de Biomedicina (IBB) and Dept. de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
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2
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Hammler D, Stuber K, Offensperger F, Scheffner M, Zumbusch A, Marx A. Fluorescently Labelled ATP Analogues for Direct Monitoring of Ubiquitin Activation. Chemistry 2020; 26:6279-6284. [PMID: 32154932 PMCID: PMC7317923 DOI: 10.1002/chem.202001091] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 03/06/2020] [Indexed: 12/18/2022]
Abstract
Simple and robust assays to monitor enzymatic ATP cleavage with high efficiency in real‐time are scarce. To address this shortcoming, we developed fluorescently labelled adenosine tri‐, tetra‐ and pentaphosphate analogues of ATP. The novel ATP analogues bear — in contrast to earlier reports — only a single acridone‐based dye at the terminal phosphate group. The dye's fluorescence is quenched by the adenine component of the ATP analogue and is restored upon cleavage of the phosphate chain and dissociation of the dye from the adenosine moiety. Thereby the activity of ATP‐cleaving enzymes can be followed in real‐time. We demonstrate this proficiency for ubiquitin activation by the ubiquitin‐activating enzymes UBA1 and UBA6 which represents the first step in an enzymatic cascade leading to the covalent attachment of ubiquitin to substrate proteins, a process that is highly conserved from yeast to humans. We found that the efficiency to serve as cofactor for UBA1/UBA6 very much depends on the length of the phosphate chain of the ATP analogue: triphosphates are used poorly while pentaphosphates are most efficiently processed. Notably, the novel pentaphosphate‐harbouring ATP analogue supersedes the efficiency of recently reported dual‐dye labelled analogues and thus, is a promising candidate for broad applications.
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Affiliation(s)
- Daniel Hammler
- Department of ChemistryUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
| | - Katrin Stuber
- Department of ChemistryUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
- Department of BiologyUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
| | - Fabian Offensperger
- Department of BiologyUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
| | - Martin Scheffner
- Department of BiologyUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
| | - Andreas Zumbusch
- Department of Chemistry and Center for Applied PhotonicsUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
| | - Andreas Marx
- Department of ChemistryUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
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3
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Varejão N, Ibars E, Lascorz J, Colomina N, Torres-Rosell J, Reverter D. DNA activates the Nse2/Mms21 SUMO E3 ligase in the Smc5/6 complex. EMBO J 2018; 37:embj.201798306. [PMID: 29769404 DOI: 10.15252/embj.201798306] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 04/11/2018] [Accepted: 04/20/2018] [Indexed: 11/09/2022] Open
Abstract
Modification of chromosomal proteins by conjugation to SUMO is a key step to cope with DNA damage and to maintain the integrity of the genome. The recruitment of SUMO E3 ligases to chromatin may represent one layer of control on protein sumoylation. However, we currently do not understand how cells upregulate the activity of E3 ligases on chromatin. Here we show that the Nse2 SUMO E3 in the Smc5/6 complex, a critical player during recombinational DNA repair, is directly stimulated by binding to DNA Activation of sumoylation requires the electrostatic interaction between DNA and a positively charged patch in the ARM domain of Smc5, which acts as a DNA sensor that subsequently promotes a stimulatory activation of the E3 activity in Nse2. Specific disruption of the interaction between the ARM of Smc5 and DNA sensitizes cells to DNA damage, indicating that this mechanism contributes to DNA repair. These results reveal a mechanism to enhance a SUMO E3 ligase activity by direct DNA binding and to restrict sumoylation in the vicinity of those Smc5/6-Nse2 molecules engaged on DNA.
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Affiliation(s)
- Nathalia Varejão
- Institut de Biotecnologia i de Biomedicina (IBB), Department of de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Eva Ibars
- Institut de Recerca Biomèdica de Lleida (IRBLLEIDA), Department of Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - Jara Lascorz
- Institut de Biotecnologia i de Biomedicina (IBB), Department of de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Neus Colomina
- Institut de Recerca Biomèdica de Lleida (IRBLLEIDA), Department of Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - Jordi Torres-Rosell
- Institut de Recerca Biomèdica de Lleida (IRBLLEIDA), Department of Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - David Reverter
- Institut de Biotecnologia i de Biomedicina (IBB), Department of de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain
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4
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Naik MT, Kang M, Ho CC, Liao PH, Hsieh YL, Naik NM, Wang SH, Chang I, Shih HM, Huang TH. Molecular mechanism of K65 acetylation-induced attenuation of Ubc9 and the NDSM interaction. Sci Rep 2017; 7:17391. [PMID: 29234076 PMCID: PMC5727262 DOI: 10.1038/s41598-017-17465-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 11/27/2017] [Indexed: 11/09/2022] Open
Abstract
The negatively charged amino acid-dependent sumoylation motif (NDSM) carries an additional stretch of acidic residues downstream of the consensus Ψ-K-x-E/D sumoylation motif. We have previously shown that acetylation of the SUMO E2 conjugase enzyme, Ubc9, at K65 downregulates its binding to the NDSM and renders a selective decrease in sumoylation of substrates with the NDSM motif. Here, we provide detailed structural, thermodynamic, and kinetics results of the interactions between Ubc9 and its K65 acetylated variant (Ac-Ubc9K65) with three NDSMs derived from Elk1, CBP, and Calpain2 to rationalize the mechanism beneath this reduced binding. Our nuclear magnetic resonance (NMR) data rule out a direct interaction between the NDSM and the K65 residue of Ubc9. Similarly, we found that NDSM binding was entropy-driven and unlikely to be affected by the negative charge by K65 acetylation. Moreover our NMR, mutagenesis and molecular dynamics simulation studies defined the sequence of the NDSM as Ψ-K-x-E/D-x1-x2-(x3/E/D)-(x4/E/D)-xn and determined that K74 and K76 were critical Ubc9 residues interacting with the negatively charged residues of the NDSM.
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Affiliation(s)
- Mandar T Naik
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan.,Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, Rhode Island, 02903, USA
| | - Mooseok Kang
- Department of Physics, Pusan National University, Busan, 46241, Korea
| | - Chun-Chen Ho
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan
| | - Pei-Hsin Liao
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan
| | - Yung-Lin Hsieh
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan
| | - Nandita M Naik
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan
| | - Szu-Huan Wang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan
| | - Iksoo Chang
- Center for Proteome Biophysics, Department of Brain and Cognitive Sciences, DGIST, Daegu, 42988, Korea.
| | - Hsiu-Ming Shih
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan. .,Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County, 35053, Taiwan.
| | - Tai-Huang Huang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan.
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5
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Hendriks IA, D'Souza RC, Chang JG, Mann M, Vertegaal ACO. System-wide identification of wild-type SUMO-2 conjugation sites. Nat Commun 2015; 6:7289. [PMID: 26073453 PMCID: PMC4490555 DOI: 10.1038/ncomms8289] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 04/26/2015] [Indexed: 12/18/2022] Open
Abstract
SUMOylation is a reversible post-translational modification (PTM) regulating all nuclear processes. Identification of SUMOylation sites by mass spectrometry (MS) has been hampered by bulky tryptic fragments, which thus far necessitated the use of mutated SUMO. Here we present a SUMO-specific protease-based methodology which circumvents this problem, dubbed Protease-Reliant Identification of SUMO Modification (PRISM). PRISM allows for detection of SUMOylated proteins as well as identification of specific sites of SUMOylation while using wild-type SUMO. The method is generic and could be widely applied to study lysine PTMs. We employ PRISM in combination with high-resolution MS to identify SUMOylation sites from HeLa cells under standard growth conditions and in response to heat shock. We identified 751 wild-type SUMOylation sites on endogenous proteins, including 200 dynamic SUMO sites in response to heat shock. Thus, we have developed a method capable of quantitatively studying wild-type mammalian SUMO at the site-specific and system-wide level. Tryptic digestion of SUMOylated proteins generates large peptides, rendering proteomic characterisation of this post-translational modification particularly challenging unless mutant SUMO is used. Hendriks et al. present a method that allows the quantitative identification of wild-type SUMO sites.
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Affiliation(s)
- Ivo A Hendriks
- Department of Molecular Cell Biology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Rochelle C D'Souza
- Department for Proteomics and Signal Transduction, Max Planck Institute for Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Jer-Gung Chang
- Department of Molecular Cell Biology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Matthias Mann
- Department for Proteomics and Signal Transduction, Max Planck Institute for Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Alfred C O Vertegaal
- Department of Molecular Cell Biology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
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6
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Leyva MJ, Kim YS, Peach ML, Schneekloth JS. Synthetic derivatives of the SUMO consensus sequence provide a basis for improved substrate recognition. Bioorg Med Chem Lett 2015; 25:2146-51. [PMID: 25881829 PMCID: PMC6341477 DOI: 10.1016/j.bmcl.2015.03.069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/21/2015] [Accepted: 03/24/2015] [Indexed: 12/21/2022]
Abstract
Protein sumoylation is a dynamic posttranslational modification that regulates a diverse subset of the proteome. The mechanism by which sumoylation enzymes recognize their cognate substrates is unclear, and the consequences of sumoylation remain difficult to predict. While small molecule probes of the sumoylation process could be valuable for understanding SUMO biology, few small molecules that modulate this process exist. Here, we report the synthesis and evaluation of over 600 oxime-containing peptide sumoylation substrates. Our work demonstrates that higher modification efficiency can be achieved with non-natural side chains that deviate substantially from the consensus site requirement of a hydrophobic substituent. Furthermore, docking studies suggest that these improved substrates mimic binding interactions that are used by other endogenous protein sequences through tertiary interactions. The development of these high efficiency substrates provides key mechanistic insights toward specific recognition of low molecular weight species in the sumoylation pathway.
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Affiliation(s)
- Melissa J Leyva
- Chemical Biology Laboratory, National Cancer Institute, 376 Boyles St., Frederick, MD 21702, USA
| | - Yeong Sang Kim
- Chemical Biology Laboratory, National Cancer Institute, 376 Boyles St., Frederick, MD 21702, USA
| | - Megan L Peach
- Basic Science Program, Chemical Biology Laboratory, Leidos Biomedical Research, Inc., National Cancer Institute, 376 Boyles St., Frederick, MD 21702, USA
| | - John S Schneekloth
- Chemical Biology Laboratory, National Cancer Institute, 376 Boyles St., Frederick, MD 21702, USA.
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7
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Lee D, Kraus A, Prins D, Groenendyk J, Aubry I, Liu WX, Li HD, Julien O, Touret N, Sykes BD, Tremblay ML, Michalak M. UBC9-dependent association between calnexin and protein tyrosine phosphatase 1B (PTP1B) at the endoplasmic reticulum. J Biol Chem 2015; 290:5725-38. [PMID: 25586181 DOI: 10.1074/jbc.m114.635474] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Calnexin is a type I integral endoplasmic reticulum (ER) membrane protein, molecular chaperone, and a component of the translocon. We discovered a novel interaction between the calnexin cytoplasmic domain and UBC9, a SUMOylation E2 ligase, which modified the calnexin cytoplasmic domain by the addition of SUMO. We demonstrated that calnexin interaction with the SUMOylation machinery modulates an interaction with protein tyrosine phosphatase 1B (PTP1B), an ER-associated protein tyrosine phosphatase involved in the negative regulation of insulin and leptin signaling. We showed that calnexin and PTP1B form UBC9-dependent complexes, revealing a previously unrecognized contribution of calnexin to the retention of PTP1B at the ER membrane. This work shows that the SUMOylation machinery links two ER proteins from divergent pathways to potentially affect cellular protein quality control and energy metabolism.
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Affiliation(s)
- Dukgyu Lee
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Allison Kraus
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Daniel Prins
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Jody Groenendyk
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Isabelle Aubry
- McGill Cancer Centre, Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Wen-Xin Liu
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Hao-Dong Li
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Olivier Julien
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Nicolas Touret
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Brian D Sykes
- From the Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada and
| | - Michel L Tremblay
- McGill Cancer Centre, Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Marek Michalak
- McGill Cancer Centre, Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
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8
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Coey CT, Fitzgerald ME, Maiti A, Reiter KH, Guzzo CM, Matunis MJ, Drohat AC. E2-mediated small ubiquitin-like modifier (SUMO) modification of thymine DNA glycosylase is efficient but not selective for the enzyme-product complex. J Biol Chem 2014; 289:15810-9. [PMID: 24753249 DOI: 10.1074/jbc.m114.572081] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Thymine DNA glycosylase (TDG) initiates the repair of G·T mismatches that arise by deamination of 5-methylcytosine (mC), and it excises 5-formylcytosine and 5-carboxylcytosine, oxidized forms of mC. TDG functions in active DNA demethylation and is essential for embryonic development. TDG forms a tight enzyme-product complex with abasic DNA, which severely impedes enzymatic turnover. Modification of TDG by small ubiquitin-like modifier (SUMO) proteins weakens its binding to abasic DNA. It was proposed that sumoylation of product-bound TDG regulates product release, with SUMO conjugation and deconjugation needed for each catalytic cycle, but this model remains unsubstantiated. We examined the efficiency and specificity of TDG sumoylation using in vitro assays with purified E1 and E2 enzymes, finding that TDG is modified efficiently by SUMO-1 and SUMO-2. Remarkably, we observed similar modification rates for free TDG and TDG bound to abasic or undamaged DNA. To examine the conjugation step directly, we determined modification rates (kobs) using preformed E2∼SUMO-1 thioester. The hyperbolic dependence of kobs on TDG concentration gives kmax = 1.6 min(-1) and K1/2 = 0.55 μM, suggesting that E2∼SUMO-1 has higher affinity for TDG than for the SUMO targets RanGAP1 and p53 (peptide). Whereas sumoylation substantially weakens TDG binding to DNA, TDG∼SUMO-1 still binds relatively tightly to AP-DNA (Kd ∼50 nM). Although E2∼SUMO-1 exhibits no specificity for product-bound TDG, the relatively high conjugation efficiency raises the possibility that E2-mediated sumoylation could stimulate product release in vivo. This and other implications for the biological role and mechanism of TDG sumoylation are discussed.
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Affiliation(s)
- Christopher T Coey
- From the Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201 and
| | - Megan E Fitzgerald
- From the Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201 and
| | - Atanu Maiti
- From the Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201 and
| | - Katherine H Reiter
- the Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, Maryland 21205
| | - Catherine M Guzzo
- the Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, Maryland 21205
| | - Michael J Matunis
- the Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, Maryland 21205
| | - Alexander C Drohat
- From the Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201 and
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9
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Ward JD, Bojanala N, Bernal T, Ashrafi K, Asahina M, Yamamoto KR. Sumoylated NHR-25/NR5A regulates cell fate during C. elegans vulval development. PLoS Genet 2013; 9:e1003992. [PMID: 24348269 PMCID: PMC3861103 DOI: 10.1371/journal.pgen.1003992] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 10/16/2013] [Indexed: 11/19/2022] Open
Abstract
Individual metazoan transcription factors (TFs) regulate distinct sets of genes depending on cell type and developmental or physiological context. The precise mechanisms by which regulatory information from ligands, genomic sequence elements, co-factors, and post-translational modifications are integrated by TFs remain challenging questions. Here, we examine how a single regulatory input, sumoylation, differentially modulates the activity of a conserved C. elegans nuclear hormone receptor, NHR-25, in different cell types. Through a combination of yeast two-hybrid analysis and in vitro biochemistry we identified the single C. elegans SUMO (SMO-1) as an NHR-25 interacting protein, and showed that NHR-25 is sumoylated on at least four lysines. Some of the sumoylation acceptor sites are in common with those of the NHR-25 mammalian orthologs SF-1 and LRH-1, demonstrating that sumoylation has been strongly conserved within the NR5A family. We showed that NHR-25 bound canonical SF-1 binding sequences to regulate transcription, and that NHR-25 activity was enhanced in vivo upon loss of sumoylation. Knockdown of smo-1 mimicked NHR-25 overexpression with respect to maintenance of the 3° cell fate in vulval precursor cells (VPCs) during development. Importantly, however, overexpression of unsumoylatable alleles of NHR-25 revealed that NHR-25 sumoylation is critical for maintaining 3° cell fate. Moreover, SUMO also conferred formation of a developmental time-dependent NHR-25 concentration gradient across the VPCs. That is, accumulation of GFP-tagged NHR-25 was uniform across VPCs at the beginning of development, but as cells began dividing, a smo-1-dependent NHR-25 gradient formed with highest levels in 1° fated VPCs, intermediate levels in 2° fated VPCs, and low levels in 3° fated VPCs. We conclude that sumoylation operates at multiple levels to affect NHR-25 activity in a highly coordinated spatial and temporal manner.
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Affiliation(s)
- Jordan D. Ward
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, United States of America
| | - Nagagireesh Bojanala
- Institute of Parasitology, Biology Centre ASCR, Ceske Budejovice, Czech Republic
- University of South Bohemia, Ceske Budejovice, Czech Republic
| | - Teresita Bernal
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, United States of America
| | - Kaveh Ashrafi
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - Masako Asahina
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, United States of America
- Institute of Parasitology, Biology Centre ASCR, Ceske Budejovice, Czech Republic
- University of South Bohemia, Ceske Budejovice, Czech Republic
- * E-mail: (MA); (KRY)
| | - Keith R. Yamamoto
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail: (MA); (KRY)
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10
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Berndsen CE, Wolberger C. A spectrophotometric assay for conjugation of ubiquitin and ubiquitin-like proteins. Anal Biochem 2011; 418:102-10. [PMID: 21771579 PMCID: PMC3178097 DOI: 10.1016/j.ab.2011.06.034] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 06/23/2011] [Accepted: 06/24/2011] [Indexed: 01/20/2023]
Abstract
Ubiquitination is a widely studied regulatory modification involved in protein degradation, DNA damage repair, and the immune response. Ubiquitin is conjugated to a substrate lysine in an enzymatic cascade involving an E1 ubiquitin-activating enzyme, an E2 ubiquitin-conjugating enzyme, and an E3 ubiquitin ligase. Assays for ubiquitin conjugation include electrophoretic mobility shift assays and detection of epitope-tagged or radiolabeled ubiquitin, which are difficult to quantitate accurately and are not amenable to high-throughput screening. We have developed a colorimetric assay that quantifies ubiquitin conjugation by monitoring pyrophosphate released in the first enzymatic step in ubiquitin transfer, the ATP-dependent charging of the E1 enzyme. The assay is rapid, does not rely on radioactive labeling, and requires only a spectrophotometer for detection of pyrophosphate formation. We show that pyrophosphate production by E1 is dependent on ubiquitin transfer and describe how to optimize assay conditions to measure E1, E2, and E3 activity. The kinetics of polyubiquitin chain formation by Ubc13-Mms2 measured by this assay are similar to those determined by gel-based assays, indicating that the data produced by this method are comparable to methods that measure ubiquitin transfer directly. This assay is adaptable to high-throughput screening of ubiquitin and ubiquitin-like conjugating enzymes.
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Affiliation(s)
- Christopher E Berndsen
- Department of Biophysics and Biophysical Chemistry, Howard Hughes Medical Institute and the Johns Hopkins University School of Medicine, Baltimore, MD 21202, USA
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11
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Saito K, Kagawa W, Suzuki T, Suzuki H, Yokoyama S, Saitoh H, Tashiro S, Dohmae N, Kurumizaka H. The putative nuclear localization signal of the human RAD52 protein is a potential sumoylation site. J Biochem 2010; 147:833-42. [PMID: 20190268 DOI: 10.1093/jb/mvq020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
RAD52, a key factor in homologous recombination (HR), plays important roles in both RAD51-dependent and -independent HR pathways. Several studies have suggested a link between the functional regulation of RAD52 and the protein modification by a small ubiquitin-like modifier (SUMO). However, the molecular mechanism underlying the regulation of RAD52 by SUMO is unknown. To begin investigating this mechanism, we identified possible target sites for sumoylation in the human RAD52 protein by preparing a RAD52-SUMO complex using an established Escherichia coli sumoylation system. Mass spectrometry and amino acid sequencing of the enzymatically digested fragments of the purified complex revealed that the putative nuclear localization signal located near the C terminus of RAD52 was sumoylated. Biochemical studies of the RAD52-SUMO complex suggested that sumoylation at the identified site has no apparent effect on the DNA binding, D-loop formation, ssDNA annealing and RAD51-binding activities of RAD52. On the other hand, visualization of the GFP-fused RAD52 protein in the human cell that contained mutations at the identified sumoylation sites showed clear differences in the cytosolic and nuclear distributions of the protein. These results suggest the possibility of sumoylation playing an important role in the nuclear transport of RAD52.
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Affiliation(s)
- Kengo Saito
- Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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12
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Yunus AA, Lima CD. Structure of the Siz/PIAS SUMO E3 ligase Siz1 and determinants required for SUMO modification of PCNA. Mol Cell 2009; 35:669-82. [PMID: 19748360 DOI: 10.1016/j.molcel.2009.07.013] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2009] [Revised: 05/27/2009] [Accepted: 07/13/2009] [Indexed: 10/20/2022]
Abstract
Siz1 is a founding member of the Siz/PIAS RING family of SUMO E3 ligases. The X-ray structure of an active Siz1 ligase revealed an elongated tripartite architecture comprised of an N-terminal PINIT domain, a central zinc-containing RING-like SP-RING domain, and a C-terminal domain we term the SP-CTD. Structure-based mutational analysis and biochemical studies show that the SP-RING and SP-CTD are required for activation of the E2 approximately SUMO thioester, while the PINIT domain is essential for redirecting SUMO conjugation to the proliferating cell nuclear antigen (PCNA) at lysine 164, a nonconsensus lysine residue that is not modified by the SUMO E2 in the absence of Siz1. Mutational analysis of Siz1 and PCNA revealed surfaces on both proteins that are required for efficient SUMO modification of PCNA in vitro and in vivo.
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Affiliation(s)
- Ali A Yunus
- Sloan-Kettering Institute, New York, NY 10065, USA
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13
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Mohideen F, Capili AD, Bilimoria PM, Yamada T, Bonni A, Lima CD. A molecular basis for phosphorylation-dependent SUMO conjugation by the E2 UBC9. Nat Struct Mol Biol 2009; 16:945-52. [PMID: 19684601 PMCID: PMC2771680 DOI: 10.1038/nsmb.1648] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Accepted: 06/30/2009] [Indexed: 01/11/2023]
Abstract
Phosphorylation and SUMO conjugation contribute to the spatial and temporal regulation of substrates containing phosphorylation-dependent SUMO consensus motifs (PDSM). MEF2 is a transcription factor and PDSM substrate whose modification by SUMO drives postsynaptic dendritic differentiation. NMR analysis revealed that the human SUMO E2 interacted with model substrates for phosphorylated and non-phosphorylated MEF2 in similar extended conformations. Mutational and biochemical analysis identified a basic E2 surface that enhanced SUMO conjugation to phosphorylated PDSM substrates MEF2 and HSF1, but not to non-phosphorylated MEF2 or HSF1 or the non-PDSM substrate p53. Mutant Ubc9 isoforms defective in promoting SUMO conjugation to phosphorylated MEF2 in vitro and in vivo also impair postsynaptic differentiation in organotypic cerebellar slices. These data support an E2-dependent mechanism that underlies phosphorylation-dependent SUMO conjugation in pathways that range from heat shock response to nuclear hormone signaling to brain development.
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Affiliation(s)
- Firaz Mohideen
- Program in Structural Biology, Sloan-Kettering Institute, New York, New York, USA
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14
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Heat shock protein 27 is involved in SUMO-2/3 modification of heat shock factor 1 and thereby modulates the transcription factor activity. Oncogene 2009; 28:7476-86. [PMID: 19597476 DOI: 10.1128/mcb.00103-08] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Heat shock protein 27 (HSP27) accumulates in stressed cells and helps them to survive adverse conditions. We have already shown that HSP27 has a function in the ubiquitination process that is modulated by its oligomerization/phosphorylation status. Here, we show that HSP27 is also involved in protein sumoylation, a ubiquitination-related process. HSP27 increases the number of cell proteins modified by small ubiquitin-like modifier (SUMO)-2/3 but this effect shows some selectivity as it neither affects all proteins nor concerns SUMO-1. Moreover, no such alteration in SUMO-2/3 conjugation is achievable by another HSP, such as HSP70. Heat shock factor 1 (HSF1), a transcription factor responsible for HSP expression, is one of the targets of HSP27. In stressed cells, HSP27 enters the nucleus and, in the form of large oligomers, binds to HSF1 and induces its modification by SUMO-2/3 on lysine 298. HSP27-induced HSF1 modification by SUMO-2/3 takes place downstream of the transcription factor phosphorylation on S303 and S307 and does not affect its DNA-binding ability. In contrast, this modification blocks HSF1 transactivation capacity. These data show that HSP27 exerts a feedback inhibition of HSF1 transactivation and enlighten the strictly regulated interplay between HSPs and HSF1. As we also show that HSP27 binds to the SUMO-E2-conjugating enzyme, Ubc9, our study raises the possibility that HSP27 may act as a SUMO-E3 ligase specific for SUMO-2/3.
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15
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Makhnevych T, Sydorskyy Y, Xin X, Srikumar T, Vizeacoumar FJ, Jeram SM, Li Z, Bahr S, Andrews BJ, Boone C, Raught B. Global map of SUMO function revealed by protein-protein interaction and genetic networks. Mol Cell 2009; 33:124-35. [PMID: 19150434 DOI: 10.1016/j.molcel.2008.12.025] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Revised: 10/06/2008] [Accepted: 12/29/2008] [Indexed: 12/27/2022]
Abstract
Systematic functional genomics approaches were used to map a network centered on the small ubiquitin-related modifier (SUMO) system. Over 250 physical interactions were identified using the SUMO protein as bait in affinity purification-mass spectrometry and yeast two-hybrid screens. More than 500 genes and 1400 synthetic genetic interactions were mapped by synthetic genetic array (SGA) analysis using eight different SUMO pathway query genes. The resultant global SUMO network highlights its role in 15 major biological processes and better defines functional relationships between the different components of the SUMO pathway. Using this information-rich resource, we have identified roles for the SUMO system in the function of the AAA ATPase Cdc48p, the regulation of lipid metabolism, localization of the ATP-dependent endonuclease Dna2p, and recovery from the DNA-damage checkpoint.
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Affiliation(s)
- Taras Makhnevych
- Banting and Best Department of Medical Research, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON M5S3E1, Canada
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16
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Reverter D, Lima CD. Preparation of SUMO proteases and kinetic analysis using endogenous substrates. Methods Mol Biol 2009; 497:225-39. [PMID: 19107421 PMCID: PMC2771683 DOI: 10.1007/978-1-59745-566-4_15] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
SUMO proteases catalyze two reactions, deconjugation of SUMO from substrates and processing of precursor SUMO isoforms to prepare SUMO for conjugation. The SUMO protease family includes two members in yeast (Ulp1 and Ulp2) and as many as six members in human (SENP1-3, SENP5-7). SENP/Ulp proteases each contain conserved C-terminal domains that catalyze protease activity. The C-terminal protease domains exhibit unique specificities during SUMO processing and deconjugation in vitro. While there are many available reagents to assess these activities, including fusion proteins and chemically modified SUMO isoforms, our studies have indicated that the composition of substrates C-terminal to the scissile bond can substantively influence the activity of the protease. As such, we have relied extensively on assays that utilize endogenous substrates, namely wild-type SUMO precursors and SUMO conjugated substrates. In this chapter, we will describe methodological details for purification and characterization of SUMO precursors, SUMO conjugated substrates, and SUMO proteases. We will also describe methods for kinetic analysis of SUMO deconjugation and maturation using endogenous substrates.
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Affiliation(s)
- David Reverter
- Structural Biology Program, Sloan-Kettering Institute, 1275 York Ave, New York, NY 10065, USA, Institut de Biotecnologia i de Biomedicina. Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Christopher D. Lima
- Structural Biology Program, Sloan-Kettering Institute, 1275 York Ave, New York, NY 10065, USA,To whom correspondence should be addressed. , Phone: (212) 639-8205, Fax: (212) 717-3047
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17
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Campbell LA, Faivre EJ, Show MD, Ingraham JG, Flinders J, Gross JD, Ingraham HA. Decreased recognition of SUMO-sensitive target genes following modification of SF-1 (NR5A1). Mol Cell Biol 2008; 23:292-307. [PMID: 19116244 DOI: 10.1210/me.2008-0219] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
SUMO modification of nuclear receptors, including the constitutively active receptor steroidogenic factor 1 (SF-1; NR5A1), is proposed to repress their transcriptional activity. We examined the functional and structural consequences of SF-1 sumoylation at two conserved lysines (Lys119 and Lys194) that reside adjacent to the DNA-binding domain (DBD) and ligand-binding domain (LBD), respectively. Surprisingly, while previous loss-of-function studies predicted that sumoylation at Lys194 would greatly impact SF-1 function, the conformation and coregulator recruitment of fully sumoylated SF-1 LBD protein was either unchanged or modestly impaired. Sumoylation at Lys194 also modestly reduced Ser203 phosphorylation. In contrast to these findings, sumoylation of the DBD at Lys119 resulted in a marked and selective loss of DNA binding to noncanonical SF-1 targets, such as inhibinalpha; this binding deficit was extended to all sites when the sumoylated human mutant (R92Q) protein, which exhibits lower activity, was used. Consistent with this result, the K119R mutant, compared to wild-type SF-1, was selectively recruited to a "SUMO-sensitive" site in the endogenous inhibinalpha promoter, leading to increased transcription. DNA binding and sumoylation of Lys119 appeared to be mutually exclusive, suggesting that once SF-1 is bound to DNA, sumoylation may be less important in regulating SF-1 activity. We propose that sumoylation of nuclear receptors imposes an active posttranslational mark that dampens recognition of SUMO-sensitive target genes to restrain their expression.
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Affiliation(s)
- Lioudmila A Campbell
- Department of Cellular and Molecular Pharmacology and Physiology, University of California, San Francisco, Box 0444, San Francisco, CA 94143-2611, USA
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18
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Schwamborn K, Knipscheer P, van Dijk E, van Dijk WJ, Sixma TK, Meloen RH, Langedijk JPM. SUMO assay with peptide arrays on solid support: insights into SUMO target sites. J Biochem 2008; 144:39-49. [PMID: 18344540 DOI: 10.1093/jb/mvn039] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The modification of proteins by SUMO (small ubiquitin-like modifier) regulates various cellular processes. Sumoylation often occurs on a specific lysine residue within the consensus motif psiKxE/D. However, little is known about the specificity and selectivity of SUMO target sites. We describe here a SUMO assay with peptide array on solid support for the simultaneous characterization of hundreds of different SUMO target sites. This approach was used to characterize known SUMO substrates. The position of the motif within the peptide and the amino acids flanking the acceptor site affected the efficiency of SUMO modification. Interestingly, a sequence of only four amino acids, corresponding to the SUMO consensus motif without flanking amino acids, was a bona fide target site. Analysis of a peptide library for all variants of the psiKxE/D consensus motif revealed that the first and third positions in the tetrapeptide preferably contain aromatic amino acid residues. Furthermore, by adding the SUMO E3 ligase PIAS1 to the reaction mixture, we show specific enhancement of the modification of a PIAS1-dependent SUMO substrate in this system. Overall, our results demonstrate that the sumoylation assay with peptide array on solid support can be used for the high-throughput characterization of SUMO target sites, and provide new insights into the composition, selectivity and specificity of SUMO target sites.
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Affiliation(s)
- Klaus Schwamborn
- Pepscan Therapeutics BV, Zuidersluisweg 2, 8243 RC Lelystad, the Netherlands.
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Capili AD, Lima CD. Structure and analysis of a complex between SUMO and Ubc9 illustrates features of a conserved E2-Ubl interaction. J Mol Biol 2007; 369:608-18. [PMID: 17466333 PMCID: PMC1940065 DOI: 10.1016/j.jmb.2007.04.006] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Revised: 03/23/2007] [Accepted: 04/01/2007] [Indexed: 11/21/2022]
Abstract
The SUMO E2 Ubc9 serves as a lynchpin in the SUMO conjugation pathway, interacting with the SUMO E1 during activation, with thioester linked SUMO after E1 transfer and with the substrate and SUMO E3 ligases during conjugation. Here, we describe the structure determination of a non-covalent complex between human Ubc9 and SUMO-1 at 2.4 A resolution. Non-covalent interactions between Ubc9 and SUMO are conserved in human and yeast insomuch as human Ubc9 interacts with each of the human SUMO isoforms, and yeast Ubc9 interacts with Smt3, the yeast SUMO ortholog. Structural comparisons reveal similarities to several other non-covalent complexes in the ubiquitin pathway, suggesting that the non-covalent Ubc9-SUMO interface may be important for poly-SUMO chain formation, for E2 recruitment to SUMO conjugated substrates, or for mediating E2 interactions with either E1 or E3 ligases. Biochemical analysis suggests that this surface is less important for E1 activation or di-SUMO-2 formation, but more important for E3 interactions and for poly-SUMO chain formation when the chain exceeds more than two SUMO proteins.
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Affiliation(s)
| | - Christopher D. Lima
- *To whom correspondence should be addressed. , Ph: (212) 639-8205, FAX: (212) 717-3047
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20
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Abstract
Many proteins are known to undergo small ubiquitin-related modifier (SUMO) modification by an E1-, E2-, and E3-dependent ligation process. Recognition that protein inhibitor of activated signal transducers and activators of transcription (STATs) (PIAS) proteins are SUMO E3 ligases raised the possibility that STATs may also be regulated by SUMO modification. Consistent with this possibility, a SUMO-ylation consensus site (PsiKxE; Psi indicates hydrophobic residue, and x indicates any residue) was identified in Stat1 (ie, (702)IKTE(705)), but not in other STATs. Biochemical analysis confirmed that Stat1 K(703) could be SUMO modified in vitro. Mutation of this critical lysine (ie, Stat1(K703R)) yielded a protein that, when expressed in Stat1(-/-) mouse embryonic fibroblasts (MEFs), exhibited enhanced DNA binding and nuclear retention. This was associated with modest changes in transcriptional and antiviral activity. However, mutation of the second critical residue in the SUMO consensus site, E(705) (ie, Stat1(E705A)), yielded a protein with wild-type DNA binding, nuclear retention, and transcriptional and antiviral activity. Similar observations were made when these mutants were expressed in primary Stat1(-/-) macrophages. These observations suggest that although Stat1 can uniquely be SUMO-ylated in vitro, this modification is unlikely to play an important role in regulating Stat1 activity in vivo.
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Affiliation(s)
- Li Song
- Department of Microbiology, Columbia University, New York, NY 10032, USA
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21
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Yunus AA, Lima CD. Lysine activation and functional analysis of E2-mediated conjugation in the SUMO pathway. Nat Struct Mol Biol 2006; 13:491-9. [PMID: 16732283 DOI: 10.1038/nsmb1104] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2005] [Accepted: 05/05/2006] [Indexed: 11/09/2022]
Abstract
E2 conjugating proteins that transfer ubiquitin and ubiquitin-like modifiers to substrate lysine residues must first activate the lysine nucleophile for conjugation. Genetic complementation revealed three side chains of the E2 Ubc9 that were crucial for normal growth. Kinetic analysis revealed modest binding defects but substantially lowered catalytic rates for these mutant alleles with respect to wild-type Ubc9. X-ray structures for wild-type and mutant human Ubc9-RanGAP1 complexes showed partial loss of contacts to the substrate lysine in mutant complexes. Computational analysis predicted pK perturbations for the substrate lysine, and Ubc9 mutations weakened pK suppression through improper side chain coordination. Biochemical studies with p53, RanGAP1 and the Nup358/RanBP2 E3 were used to determine rate constants and pK values, confirming both structural and computational predictions. It seems that Ubc9 uses an indirect mechanism to activate lysine for conjugation that may be conserved among E2 family members.
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Affiliation(s)
- Ali A Yunus
- Structural Biology Program, Sloan-Kettering Institute, New York, New York 10021, USA
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