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Jiang H, Miller BD, Viennet T, Kim H, Lee K, Arthanari H, Cole PA. Protein semisynthesis reveals plasticity in HECT E3 ubiquitin ligase mechanisms. Nat Chem 2024:10.1038/s41557-024-01576-z. [PMID: 39030419 DOI: 10.1038/s41557-024-01576-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 06/11/2024] [Indexed: 07/21/2024]
Abstract
Lys ubiquitination is catalysed by E3 ubiquitin ligases and is central to the regulation of protein stability and cell signalling in normal and disease states. There are gaps in our understanding of E3 mechanisms, and here we use protein semisynthesis, chemical rescue, microscale thermophoresis and other biochemical approaches to dissect the role of catalytic base/acid function and conformational interconversion in HECT-domain E3 catalysis. We demonstrate that there is plasticity in the use of the terminal side chain or backbone carboxylate for proton transfer in HECT E3 ubiquitin ligase reactions, with yeast Rsp5 orthologues appearing to be possible evolutionary intermediates. We also show that the HECT-domain ubiquitin covalent intermediate appears to eject the E2 conjugating enzyme, promoting catalytic turnover. These findings provide key mechanistic insights into how protein ubiquitination occurs and provide a framework for understanding E3 functions and regulation.
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Affiliation(s)
- Hanjie Jiang
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Bryant D Miller
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Department of Human Biology, Sattler College, Boston, MA, USA
| | - Thibault Viennet
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana Farber Cancer Institute, Boston, MA, USA
| | - Hyojeon Kim
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Kwangwoon Lee
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Haribabu Arthanari
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana Farber Cancer Institute, Boston, MA, USA
| | - Philip A Cole
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
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2
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Strassler SE, Bowles IE, Dey D, Jackman JE, Conn GL. Tied up in knots: Untangling substrate recognition by the SPOUT methyltransferases. J Biol Chem 2022; 298:102393. [PMID: 35988649 PMCID: PMC9508554 DOI: 10.1016/j.jbc.2022.102393] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 08/10/2022] [Accepted: 08/11/2022] [Indexed: 10/25/2022] Open
Abstract
The SpoU-TrmD (SPOUT) methyltransferase superfamily was designated when structural similarity was identified between the transfer RNA-modifying enzymes TrmH (SpoU) and TrmD. SPOUT methyltransferases are found in all domains of life and predominantly modify transfer RNA or ribosomal RNA substrates, though one instance of an enzyme with a protein substrate has been reported. Modifications placed by SPOUT methyltransferases play diverse roles in regulating cellular processes such as ensuring translational fidelity, altering RNA stability, and conferring bacterial resistance to antibiotics. This large collection of S-adenosyl-L-methionine-dependent methyltransferases is defined by a unique α/β fold with a deep trefoil knot in their catalytic (SPOUT) domain. Herein, we describe current knowledge of SPOUT enzyme structure, domain architecture, and key elements of catalytic function, including S-adenosyl-L-methionine co-substrate binding, beginning with a new sequence alignment that divides the SPOUT methyltransferase superfamily into four major clades. Finally, a major focus of this review will be on our growing understanding of how these diverse enzymes accomplish the molecular feat of specific substrate recognition and modification, as highlighted by recent advances in our knowledge of protein-RNA complex structures and the discovery of the dependence of one SPOUT methyltransferase on metal ion binding for catalysis. Considering the broad biological roles of RNA modifications, developing a deeper understanding of the process of substrate recognition by the SPOUT enzymes will be critical for defining many facets of fundamental RNA biology with implications for human disease.
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Affiliation(s)
- Sarah E Strassler
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA; Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, Georgia, USA
| | - Isobel E Bowles
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, Columbus, Ohio, USA
| | - Debayan Dey
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Jane E Jackman
- Department of Chemistry and Biochemistry, Center for RNA Biology and Ohio State Biochemistry Program, Columbus, Ohio, USA.
| | - Graeme L Conn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA; Graduate Program in Biochemistry, Cell and Developmental Biology, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, Georgia, USA.
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3
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Manduzio S, Kang H. RNA methylation in chloroplasts or mitochondria in plants. RNA Biol 2021; 18:2127-2135. [PMID: 33779501 PMCID: PMC8632092 DOI: 10.1080/15476286.2021.1909321] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 03/23/2021] [Indexed: 12/14/2022] Open
Abstract
Recent advances in our understanding of epitranscriptomic RNA methylation have expanded the complexity of gene expression regulation beyond epigenetic regulation involving DNA methylation and histone modifications. The instalment, removal, and interpretation of methylation marks on RNAs are carried out by writers (methyltransferases), erasers (demethylases), and readers (RNA-binding proteins), respectively. Contrary to an emerging body of evidence demonstrating the importance of RNA methylation in the diverse fates of RNA molecules, including splicing, export, translation, and decay in the nucleus and cytoplasm, their roles in plant organelles remain largely unclear and are only now being discovered. In particular, extremely high levels of methylation marks in chloroplast and mitochondrial RNAs suggest that RNA methylation plays essential roles in organellar biogenesis and functions in plants that are crucial for plant development and responses to environmental stimuli. Thus, unveiling the cellular components involved in RNA methylation in cell organelles is essential to better understand plant biology.
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Affiliation(s)
- Stefano Manduzio
- Department of Applied Biology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, South Korea
| | - Hunseung Kang
- Department of Applied Biology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, South Korea
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4
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Thomas SE, Whitehouse AJ, Brown K, Burbaud S, Belardinelli J, Sangen J, Lahiri R, Libardo M, Gupta P, Malhotra S, Boshoff HIM, Jackson M, Abell C, Coyne A, Blundell TL, Floto RA, Mendes V. Fragment-based discovery of a new class of inhibitors targeting mycobacterial tRNA modification. Nucleic Acids Res 2020; 48:8099-8112. [PMID: 32602532 PMCID: PMC7641325 DOI: 10.1093/nar/gkaa539] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 06/10/2020] [Accepted: 06/15/2020] [Indexed: 12/13/2022] Open
Abstract
Translational frameshift errors are often deleterious to the synthesis of functional proteins and could therefore be promoted therapeutically to kill bacteria. TrmD (tRNA-(N(1)G37) methyltransferase) is an essential tRNA modification enzyme in bacteria that prevents +1 errors in the reading frame during protein translation and represents an attractive potential target for the development of new antibiotics. Here, we describe the application of a structure-guided fragment-based drug discovery approach to the design of a new class of inhibitors against TrmD in Mycobacterium abscessus. Fragment library screening, followed by structure-guided chemical elaboration of hits, led to the rapid development of drug-like molecules with potent in vitro TrmD inhibitory activity. Several of these compounds exhibit activity against planktonic M. abscessus and M. tuberculosis as well as against intracellular M. abscessus and M. leprae, indicating their potential as the basis for a novel class of broad-spectrum mycobacterial drugs.
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Affiliation(s)
- Sherine E Thomas
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
| | - Andrew J Whitehouse
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Karen Brown
- University of Cambridge Molecular Immunity Unit, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
- Cambridge Centre for Lung Infection, Royal Papworth Hospital, Cambridge CB2 0AY, UK
| | - Sophie Burbaud
- University of Cambridge Molecular Immunity Unit, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Juan M Belardinelli
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Jasper Sangen
- University of Cambridge Molecular Immunity Unit, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Ramanuj Lahiri
- National Hansen's Disease Program, Healthcare Systems Bureau, Health Resources and Services Administration, Department of Health and Human Services, Baton Rouge, LA, USA
| | - Mark Daben J Libardo
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA
| | - Pooja Gupta
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
| | - Sony Malhotra
- Birkbeck College, University of London, Malet Street WC1E7HX, UK
| | - Helena I M Boshoff
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA
| | - Mary Jackson
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Chris Abell
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Anthony G Coyne
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Tom L Blundell
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
| | - Rodrigo Andres Floto
- University of Cambridge Molecular Immunity Unit, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
- Cambridge Centre for Lung Infection, Royal Papworth Hospital, Cambridge CB2 0AY, UK
| | - Vítor Mendes
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
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5
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Capraro DT, Burban DJ, Jennings PA. Unraveling Allostery in a Knotted Minimal Methyltransferase by NMR Spectroscopy. J Mol Biol 2020; 432:3018-3032. [PMID: 32135193 DOI: 10.1016/j.jmb.2020.02.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 11/17/2022]
Abstract
The methyltransferases that belong to the SpoU-TrmD family contain trefoil knots in their backbone fold. Recent structural dynamic and binding analyses of both free and bound homologs indicate that the knot within the polypeptide backbone plays a significant role in the biological activity of the molecule. The knot loops form the S-adenosyl-methionine (SAM)-binding pocket as well as participate in SAM binding and catalysis. Knots contain both at once a stable core as well as moving parts that modulate long-range motions. Here, we sought to understand allosteric effects modulated by the knotted topology. Uncovering the residues that contribute to these changes and the functional aspects of these protein motions are essential to understanding the interplay between the knot, activation of the methyltransferase, and the implications in RNA interactions. The question we sought to address is as follows: How does the knot, which constricts the backbone as well as forms the SAM-binding pocket with its three distinctive loops, affect the binding mechanism? Using a minimally tied trefoil protein as the framework for understanding the structure-function roles, we offer an unprecedented view of the conformational mechanics of the knot and its relationship to the activation of the ligand molecule. Focusing on the biophysical characterization of the knot region by NMR spectroscopy, we identify the SAM-binding region and observe changes in the dynamics of the loops that form the knot. Importantly, we also observe long-range allosteric changes in flanking helices consistent with winding/unwinding in helical propensity as the knot tightens to secure the SAM cofactor.
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Affiliation(s)
- Dominique T Capraro
- University of California, San Diego, 9500 Gilman Drive, Natural Science Building #3110, La Jolla, CA 92093, USA
| | - David J Burban
- University of California, San Diego, 9500 Gilman Drive, Natural Science Building #3110, La Jolla, CA 92093, USA
| | - Patricia A Jennings
- University of California, San Diego, 9500 Gilman Drive, Natural Science Building #3110, La Jolla, CA 92093, USA.
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6
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Abstract
The origin of protein backbone threading through a topological knot remains elusive. To understand the evolutionary origin of protein knots, in this issue of StructureKo et al. (2019) used circular permutation to untie a knotted protein. They showed that a domain-swapped dimer releases the knot and the associated high-energy state for substrate binding.
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Functional prediction, characterization, and categorization of operome from Acetoanaerobium sticklandii DSM 519. Anaerobe 2019; 61:102088. [PMID: 31425748 DOI: 10.1016/j.anaerobe.2019.102088] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 08/13/2019] [Accepted: 08/14/2019] [Indexed: 01/05/2023]
Abstract
Acetoanaerobium sticklandii DSM 519 is a hyper-ammonia producing anaerobic bacterium that can be able utilizes amino acids as sole carbon and energy sources for its growth and energetic metabolism. A lack of knowledge on its molecular machinery and 30.5% conserved hypothetical proteins (HPs; operome) hinders the successful utility in biofuel applications. In this study, we have predicted, characterized and categorized its operome whose functions are still not determined accurately using a combined bioinformatics approach. The functions of 64 of the 359 predicted HPs are involved in diverse metabolic subsystems. A. sticklandii operome has consisted of 16% Rossmann fold and 46% miscellaneous folds. Subsystems-based technology has classified 51 HPs contributing to the small-molecular reactions, 26 in macromolecular reactions and 12 in the biosynthesis of cofactors, prosthetic groups and electron carriers. A generality of functions predicted from its operome contributed to the cell cycle, amino acid metabolism, membrane transport, and regulatory processes. Many of them have duplicated functions as paralogs in this genome. A. sticklandii has the ability to compete with invading microorganisms and tolerate abiotic stresses, which can be overwhelmed by the predicted functions of its operome. Results of this study revealed that it has specialized systems for amino acid catabolism-directed solventogenesis and acidogenesis but the level of gene expression may determine the metabolic function in amino acid fermenting niches in the rumina of cattle. As shown by our analysis, the predicted functions of its operome allow us for a better understanding of the growth and physiology at systems-scale.
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Ko KT, Hu IC, Huang KF, Lyu PC, Hsu STD. Untying a Knotted SPOUT RNA Methyltransferase by Circular Permutation Results in a Domain-Swapped Dimer. Structure 2019; 27:1224-1233.e4. [DOI: 10.1016/j.str.2019.04.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/01/2019] [Accepted: 04/05/2019] [Indexed: 11/28/2022]
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9
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González-Flores YE, de Dios R, Reyes-Ramírez F, Santero E. The response of Sphingopyxis granuli strain TFA to the hostile anoxic condition. Sci Rep 2019; 9:6297. [PMID: 31000749 PMCID: PMC6472365 DOI: 10.1038/s41598-019-42768-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 04/05/2019] [Indexed: 01/02/2023] Open
Abstract
Sphingomonads comprises a group of interesting aerobic bacteria because of their ubiquity and metabolic capability of degrading many recalcitrant contaminants. The tetralin-degrader Sphingopyxis granuli strain TFA has been recently reported as able to anaerobically grow using nitrate as the alternative electron acceptor and so far is the only bacterium with this ability within the sphingomonads group. To understand how strain TFA thrives under anoxic conditions, a differential transcriptomic analysis while growing under aerobic or anoxic conditions was performed. This analysis has been validated and complemented with transcription kinetics of representative genes of different functional categories. Results show an extensive change of the expression pattern of this strain in the different conditions. Consistently, the most induced operon in anoxia codes for proteases, presumably required for extensive changes in the protein profile. Besides genes that respond to lack of oxygen in other bacteria, there are a number of genes that respond to stress or to damage of macromolecules, including genes of the SOS DNA-damage response, which suggest that anoxic conditions represent a hostile environment for this bacterium. Interestingly, growth under anoxic conditions also resulted in repression of all flagellar and type IV pilin genes, which suggested that this strain shaves its appendages off while growing in anaerobiosis.
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Affiliation(s)
- Yolanda Elisabet González-Flores
- Centro Andaluz de Biología del Desarrollo/CSIC/Universidad Pablo de Olavide/Junta de Andalucía. Departamento de Biología Molecular e Ingeniería Bioquímica, Seville, Spain
| | - Rubén de Dios
- Centro Andaluz de Biología del Desarrollo/CSIC/Universidad Pablo de Olavide/Junta de Andalucía. Departamento de Biología Molecular e Ingeniería Bioquímica, Seville, Spain
| | - Francisca Reyes-Ramírez
- Centro Andaluz de Biología del Desarrollo/CSIC/Universidad Pablo de Olavide/Junta de Andalucía. Departamento de Biología Molecular e Ingeniería Bioquímica, Seville, Spain.
| | - Eduardo Santero
- Centro Andaluz de Biología del Desarrollo/CSIC/Universidad Pablo de Olavide/Junta de Andalucía. Departamento de Biología Molecular e Ingeniería Bioquímica, Seville, Spain
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Krishnamohan A, Jackman JE. A Family Divided: Distinct Structural and Mechanistic Features of the SpoU-TrmD (SPOUT) Methyltransferase Superfamily. Biochemistry 2018; 58:336-345. [PMID: 30457841 DOI: 10.1021/acs.biochem.8b01047] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The SPOUT family of enzymes makes up the second largest of seven structurally distinct groups of methyltransferases and is named after two evolutionarily related RNA methyltransferases, SpoU and TrmD. A deep trefoil knotted domain in the tertiary structures of member enzymes defines the SPOUT family. For many years, formation of a homodimeric quaternary structure was thought to be a strict requirement for all SPOUT enzymes, critical for substrate binding and formation of the active site. However, recent structural characterization of two SPOUT members, Trm10 and Sfm1, revealed that they function as monomers without the requirement of this critical dimerization. This unusual monomeric form implies that these enzymes must exhibit a nontraditional substrate binding mode and active site architecture and may represent a new division in the SPOUT family with distinct properties removed from the dimeric enzymes. Here we discuss the mechanistic features of SPOUT enzymes with an emphasis on the monomeric members and implications of this "novel" monomeric structure on cofactor and substrate binding.
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Affiliation(s)
- Aiswarya Krishnamohan
- The Ohio State Biochemistry Program, Center for RNA Biology, and Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Jane E Jackman
- The Ohio State Biochemistry Program, Center for RNA Biology, and Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
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Kirpekar F, Hansen LH, Mundus J, Tryggedsson S, Teixeira Dos Santos P, Ntokou E, Vester B. Mapping of ribosomal 23S ribosomal RNA modifications in Clostridium sporogenes. RNA Biol 2018; 15:1060-1070. [PMID: 29947286 DOI: 10.1080/15476286.2018.1486662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
All organisms contain RNA modifications in their ribosomal RNA (rRNA), but the importance, positions and exact function of these are still not fully elucidated. Various functions such as stabilizing structures, controlling ribosome assembly and facilitating interactions have been suggested and in some cases substantiated. Bacterial rRNA contains much fewer modifications than eukaryotic rRNA. The rRNA modification patterns in bacteria differ from each other, but too few organisms have been mapped to draw general conclusions. This study maps 23S ribosomal RNA modifications in Clostridium sporogenes that can be characterized as a non-toxin producing Clostridium botulinum. Clostridia are able to sporulate and thereby survive harsh conditions, and are in general considered to be resilient to antibiotics. Selected regions of the 23S rRNA were investigated by mass spectrometry and by primer extension analysis to pinpoint modified sites and the nature of the modifications. Apparently, C. sporogenes 23S rRNA contains few modifications compared to other investigated bacteria. No modifications were identified in domain II and III of 23S rRNA. Three modifications were identified in domain IV, all of which have also been found in other organisms. Two unusual modifications were identified in domain V, methylated dihydrouridine at position U2449 and dihydrouridine at position U2500 (Escherichia coli numbering), in addition to four previously known modified positions. The enzymes responsible for the modifications were searched for in the C. sporogenes genome using BLAST with characterized enzymes as query. The search identified genes potentially coding for RNA modifying enzymes responsible for most of the found modifications.
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Affiliation(s)
- Finn Kirpekar
- a Department of Biochemistry and Molecular Biology , University of Southern Denmark , Odense , Denmark
| | - Lykke H Hansen
- a Department of Biochemistry and Molecular Biology , University of Southern Denmark , Odense , Denmark
| | - Julie Mundus
- a Department of Biochemistry and Molecular Biology , University of Southern Denmark , Odense , Denmark
| | - Stine Tryggedsson
- a Department of Biochemistry and Molecular Biology , University of Southern Denmark , Odense , Denmark
| | | | - Eleni Ntokou
- a Department of Biochemistry and Molecular Biology , University of Southern Denmark , Odense , Denmark
| | - Birte Vester
- a Department of Biochemistry and Molecular Biology , University of Southern Denmark , Odense , Denmark
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12
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Sriramoju MK, Chen Y, Lee YTC, Hsu STD. Topologically knotted deubiquitinases exhibit unprecedented mechanostability to withstand the proteolysis by an AAA+ protease. Sci Rep 2018; 8:7076. [PMID: 29728659 PMCID: PMC5935755 DOI: 10.1038/s41598-018-25470-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 04/23/2018] [Indexed: 01/03/2023] Open
Abstract
More than one thousand knotted protein structures have been identified so far, but the functional roles of these knots remain elusive. It has been postulated that backbone entanglement may provide additional mechanostability. Here, we employed a bacterial proteasome, ClpXP, to mechanically unfold 52-knotted human ubiquitin C-terminal hydrolase (UCH) paralogs from their C-termini, followed by processive translocation into the proteolytic chamber for degradation. Our results revealed unprecedentedly slow kinetics of ClpXP-mediated proteolysis for the proteasome-associated UCHL5: ten thousand times slower than that of a green fluorescence protein (GFP), which has a comparable size to the UCH domain but much higher chemical and thermal stabilities. The ClpXP-dependent mechanostability positively correlates with the intrinsic unfolding rates of the substrates, spanning over several orders of magnitude for the UCHs. The broad range of mechanostability within the same protein family may be associated with the functional requirements for their differential malleabilities.
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Affiliation(s)
| | - Yen Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei, 11529, Taiwan
| | - Yun-Tzai Cloud Lee
- Institute of Biological Chemistry, Academia Sinica, Taipei, 11529, Taiwan.,Institute of Biochemical Sciences, National Taiwan University, Taipei, 106, Taiwan
| | - Shang-Te Danny Hsu
- Institute of Biological Chemistry, Academia Sinica, Taipei, 11529, Taiwan. .,Institute of Biochemical Sciences, National Taiwan University, Taipei, 106, Taiwan.
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