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Koufaris C, Demetriadou C, Nicolaidou V, Kirmizis A. Bioinformatic Analysis Reveals the Association of Human N-Terminal Acetyltransferase Complexes with Distinct Transcriptional and Post-Transcriptional Processes. Biochem Genet 2024:10.1007/s10528-024-10860-z. [PMID: 38864963 DOI: 10.1007/s10528-024-10860-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Accepted: 06/05/2024] [Indexed: 06/13/2024]
Abstract
N-terminal acetyltransferases (NAT) are the protein complexes that deposit the abundant N-terminal acetylation (Nt-Ac) on eukaryotic proteins, with seven human complexes currently identified. Despite the increasing recognition of their biological and clinical importance, NAT regulation remains elusive. In this study, we performed a bioinformatic investigation to identify transcriptional and post-transcriptional processes that could be involved in the regulation of human NAT complexes. First, co-expression analysis of independent transcriptomic datasets revealed divergent pathway associations for human NAT, which are potentially connected to their distinct cellular functions. One interesting connection uncovered was the coordinated regulation of the NatA and proteasomal genes in cancer and immune cells, confirmed by analysis of multiple datasets and in isolated primary T cells. Another distinctive association was of NAA40 (NatD) with DNA replication, in cancer and non-cancer settings. The link between NAA40 transcription and DNA replication is potentially mediated through E2F1, which we have experimentally shown to bind the promoter of this NAT. Second, the coupled examination of transcriptomic and proteomic datasets revealed a much greater intra-complex concordance of NAT subunits at the protein compared to the transcript level, indicating the predominance of post-transcriptional processes for achieving their coordination. In agreement with this concept, we also found that the effects of somatic copy number alterations affecting NAT genes are attenuated post-transcriptionally. In conclusion, this study provides novel insights into the regulation of human NAT complexes.
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Affiliation(s)
- C Koufaris
- Epigenetics and Gene Regulation Laboratory, Department of Biological Sciences, University of Cyprus, 2109, Nicosia, Cyprus
| | - C Demetriadou
- Epigenetics and Gene Regulation Laboratory, Department of Biological Sciences, University of Cyprus, 2109, Nicosia, Cyprus
| | - V Nicolaidou
- Department of Life Sciences, University of Nicosia, Nicosia, Cyprus
| | - A Kirmizis
- Epigenetics and Gene Regulation Laboratory, Department of Biological Sciences, University of Cyprus, 2109, Nicosia, Cyprus.
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2
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Syriste L, Patel DT, Stogios PJ, Skarina T, Patel D, Savchenko A. An acetyltransferase effector conserved across Legionella species targets the eukaryotic eIF3 complex to modulate protein translation. mBio 2024; 15:e0322123. [PMID: 38335095 PMCID: PMC10936415 DOI: 10.1128/mbio.03221-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 01/16/2024] [Indexed: 02/12/2024] Open
Abstract
The survival of Legionella spp. as intracellular pathogens relies on the combined action of protein effectors delivered inside their eukaryotic hosts by the Dot/Icm (defective in organelle trafficking/intracellular multiplication) type IVb secretion system. The specific repertoire of effector arsenals varies dramatically across over 60 known species of this genera with Legionella pneumophila responsible for most cases of Legionnaires' disease in humans encoding over 360 Dot/Icm effectors. However, a small subset of "core" effectors appears to be conserved across all Legionella species raising an intriguing question of their role in these bacteria's pathogenic strategy, which for most of these effectors remains unknown. L. pneumophila Lpg0103 effector, also known as VipF, represents one of the core effector families that features a tandem of Gcn5-related N-acetyltransferase (GNAT) domains. Here, we present the crystal structure of the Lha0223, the VipF representative from Legionella hackeliae in complex with acetyl-coenzyme A determined to 1.75 Å resolution. Our structural analysis suggested that this effector family shares a common fold with the two GNAT domains forming a deep groove occupied by residues conserved across VipF homologs. Further analysis suggested that only the C-terminal GNAT domain of VipF effectors retains the active site composition compatible with catalysis, whereas the N-terminal GNAT domain binds the ligand in a non-catalytical mode. We confirmed this by in vitro enzymatic assays which revealed VipF activity not only against generic small molecule substrates, such as chloramphenicol, but also against poly-L-lysine and histone-derived peptides. We identified the human eukaryotic translation initiation factor 3 (eIF3) complex co-precipitating with Lpg0103 and demonstrated the direct interaction between the several representatives of the VipF family, including Lpg0103 and Lha0223 with the K subunit of eIF3. According to our data, these interactions involve primarily the C-terminal tail of eIF3-K containing two lysine residues that are acetylated by VipF. VipF catalytic activity results in the suppression of eukaryotic protein translation in vitro, revealing the potential function of VipF "core" effectors in Legionella's pathogenic strategy.IMPORTANCEBy translocating effectors inside the eukaryotic host cell, bacteria can modulate host cellular processes in their favor. Legionella species, which includes the pneumonia-causing Legionella pneumophila, encode a widely diverse set of effectors with only a small subset that is conserved across this genus. Here, we demonstrate that one of these conserved effector families, represented by L. pneumophila VipF (Lpg0103), is a tandem Gcn5-related N-acetyltransferase interacting with the K subunit of human eukaryotic initiation factor 3 complex. VipF catalyzes the acetylation of lysine residues on the C-terminal tail of the K subunit, resulting in the suppression of eukaryotic translation initiation factor 3-mediated protein translation in vitro. These new data provide the first insight into the molecular function of this pathogenic factor family common across Legionellae.
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Affiliation(s)
- Lukas Syriste
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Deepak T. Patel
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Peter J. Stogios
- Department of Chemical Engineering and Applied Chemistry, Toronto University, Toronto, Ontario, Canada
| | - Tatiana Skarina
- Department of Chemical Engineering and Applied Chemistry, Toronto University, Toronto, Ontario, Canada
| | - Dhruvin Patel
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Alexei Savchenko
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
- Department of Chemical Engineering and Applied Chemistry, Toronto University, Toronto, Ontario, Canada
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3
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Ho KH, Pan KF, Cheng TY, Chien MH, Hua KT. Multiple impacts of Naa10p on cancer progression: Molecular functions and clinical prospects. Biochim Biophys Acta Rev Cancer 2023; 1878:188973. [PMID: 37659460 DOI: 10.1016/j.bbcan.2023.188973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/27/2023] [Accepted: 08/28/2023] [Indexed: 09/04/2023]
Abstract
Nα-acetyltransferase 10 protein (Naa10p) is known as the catalytic subunit of N-terminal acetyltransferases A (NatA) complex, associating with Naa15p to acetylate N-termini of the human proteome. Recent investigations have unveiled additional functions for Naa10p, encompassing lysine ε-acetylation and acetyltransferase-independent activities. Its pleiotropic roles have been implicated in diverse physiological and pathological contexts. Emerging evidence has implicated Naa10p in cancer progression, demonstrating dual attributes as an oncogene or a tumor suppressor contingent on the cancer type and acetyltransferase activity context. In this comprehensive review, we present a pan-cancer analysis aimed at elucidating the intricacies underlying Naa10p dysregulation in cancer. Our findings propose the potential involvement of c-Myc as a modulatory factor influencing Naa10p expression. Moreover, we provide a consolidated summary of recent advancements in understanding the intricate molecular underpinnings through which Naa10p contributes to cancer cell proliferation and metastasis. Furthermore, we delve into the multifaceted nature of Naa10p's roles in regulating cancer behaviors, potentially attributed to its interactions with a repertoire of partner proteins. Through an exhaustive exploration of Naa10p's functions, spanning its acetylation activity and acetyltransferase-independent functionalities, this review offers novel insights with implications for targeted therapeutic strategies involving this pivotal protein in the realm of cancer therapeutics.
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Affiliation(s)
- Kuo-Hao Ho
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Ke-Fan Pan
- Department of Medical Education and Research, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan; Division of General Surgery, Department of Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan; Division of Colorectal Surgery, Department of Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan; Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan.
| | - Tsu-Yao Cheng
- Department of Laboratory Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan; Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
| | - Ming-Hsien Chien
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; TMU Research Center of Cancer Translational Medicine, Taipei Medical University, Taipei, Taiwan; Pulmonary Research Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan; Traditional Herbal Medicine Research Center, Taipei Medical University Hospital, Taipei, Taiwan.
| | - Kuo-Tai Hua
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan.
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4
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Xu M, Liu X, Li X, Chen L, Li S, Sun B, Xu D, Ran T, Wang W. Crystal structure of prodigiosin binding protein PgbP, a GNAT family protein, in Serratia marcescens FS14. Biochem Biophys Res Commun 2023; 640:73-79. [PMID: 36502634 DOI: 10.1016/j.bbrc.2022.12.006] [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: 11/23/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
Acetylation is a conserved modification catalyzed by acetyltransferases that play prominent roles in a large number of biological processes. Members of the general control non-repressible 5 (GCN5)-N-acetyltransferase (GNAT) protein superfamily are widespread in all kingdoms of life and are characterized by highly conserved catalytic fold, and can acetylate a wide range of substrates. Although the structures and functions of numerous eukaryotic GNATs have been identified thus far, many GNATs in microorganisms remain structurally and functionally undescribed. Here, we determined the crystal structure of the putative GCN5-N-acetyltransferase PgbP in complex with CoA in Serratia marcescens FS14. Structural analysis revealed that the PgbP dimer has two cavities, each of which binds a CoA molecule via conserved motifs of the GNAT family. In addition, the biochemical studies showed that PgbP is a prodigiosin-binding protein with high thermal stability. To our knowledge, this is the first view of GNAT binding to secondary metabolites and it is also the first report of prodigiosin binding protein. Molecular docking and mutation experiments indicated that prodigiosin binds to the substrate binding site of PgbP. The structure-function analyses presented here broaden our understanding of the multifunctionality of GNAT family members and may infer the mechanism of the multiple biological activities of prodigiosin.
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Affiliation(s)
- Mengxue Xu
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, 210095, Nanjing, China
| | - Xia Liu
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, 210095, Nanjing, China
| | - Xiaoyan Li
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, 210095, Nanjing, China
| | - Lin Chen
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, 210095, Nanjing, China
| | - Shengzhe Li
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, 210095, Nanjing, China
| | - Bo Sun
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201204, China; Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China
| | - Dongqing Xu
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, 210095, Nanjing, China.
| | - Tingting Ran
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, 210095, Nanjing, China.
| | - Weiwu Wang
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, 210095, Nanjing, China.
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5
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Donnarumma F, Tucci V, Ambrosino C, Altucci L, Carafa V. NAA60 (HAT4): the newly discovered bi-functional Golgi member of the acetyltransferase family. Clin Epigenetics 2022; 14:182. [PMID: 36539894 PMCID: PMC9769039 DOI: 10.1186/s13148-022-01402-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022] Open
Abstract
Chromatin structural organization, gene expression and proteostasis are intricately regulated in a wide range of biological processes, both physiological and pathological. Protein acetylation, a major post-translational modification, is tightly involved in interconnected biological networks, modulating the activation of gene transcription and protein action in cells. A very large number of studies describe the pivotal role of the so-called acetylome (accounting for more than 80% of the human proteome) in orchestrating different pathways in response to stimuli and triggering severe diseases, including cancer. NAA60/NatF (N-terminal acetyltransferase F), also named HAT4 (histone acetyltransferase type B protein 4), is a newly discovered acetyltransferase in humans modifying N-termini of transmembrane proteins starting with M-K/M-A/M-V/M-M residues and is also thought to modify lysine residues of histone H4. Because of its enzymatic features and unusual cell localization on the Golgi membrane, NAA60 is an intriguing acetyltransferase that warrants biochemical and clinical investigation. Although it is still poorly studied, this review summarizes current findings concerning the structural hallmarks and biological role of this novel targetable epigenetic enzyme.
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Affiliation(s)
- Federica Donnarumma
- grid.428067.f0000 0004 4674 1402Biogem, Molecular Biology and Genetics Research Institute, Ariano Irpino, Italy
| | - Valeria Tucci
- grid.428067.f0000 0004 4674 1402Biogem, Molecular Biology and Genetics Research Institute, Ariano Irpino, Italy ,grid.9841.40000 0001 2200 8888Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, Vico De Crecchio7, 80138 Naples, Italy
| | - Concetta Ambrosino
- grid.428067.f0000 0004 4674 1402Biogem, Molecular Biology and Genetics Research Institute, Ariano Irpino, Italy ,grid.47422.370000 0001 0724 3038Department of Science and Technology, University of Sannio, Benevento, Italy
| | - Lucia Altucci
- grid.428067.f0000 0004 4674 1402Biogem, Molecular Biology and Genetics Research Institute, Ariano Irpino, Italy ,grid.9841.40000 0001 2200 8888Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, Vico De Crecchio7, 80138 Naples, Italy
| | - Vincenzo Carafa
- grid.9841.40000 0001 2200 8888Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, Vico De Crecchio7, 80138 Naples, Italy
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Pożoga M, Armbruster L, Wirtz M. From Nucleus to Membrane: A Subcellular Map of the N-Acetylation Machinery in Plants. Int J Mol Sci 2022; 23:ijms232214492. [PMID: 36430970 PMCID: PMC9692967 DOI: 10.3390/ijms232214492] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/14/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022] Open
Abstract
N-terminal acetylation (NTA) is an ancient protein modification conserved throughout all domains of life. N-terminally acetylated proteins are present in the cytosol, the nucleus, the plastids, mitochondria and the plasma membrane of plants. The frequency of NTA differs greatly between these subcellular compartments. While up to 80% of cytosolic and 20-30% of plastidic proteins are subject to NTA, NTA of mitochondrial proteins is rare. NTA alters key characteristics of proteins such as their three-dimensional structure, binding properties and lifetime. Since the majority of proteins is acetylated by five ribosome-bound N-terminal acetyltransferases (Nats) in yeast and humans, NTA was long perceived as an exclusively co-translational process in eukaryotes. The recent characterization of post-translationally acting plant Nats, which localize to the plasma membrane and the plastids, has challenged this view. Moreover, findings in humans, yeast, green algae and higher plants uncover differences in the cytosolic Nat machinery of photosynthetic and non-photosynthetic eukaryotes. These distinctive features of the plant Nat machinery might constitute adaptations to the sessile lifestyle of plants. This review sheds light on the unique role of plant N-acetyltransferases in development and stress responses as well as their evolution-driven adaptation to function in different cellular compartments.
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7
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Asensio T, Dian C, Boyer JB, Rivière F, Meinnel T, Giglione C. A Continuous Assay Set to Screen and Characterize Novel Protein N-Acetyltransferases Unveils Rice General Control Non-repressible 5-Related N-Acetyltransferase2 Activity. FRONTIERS IN PLANT SCIENCE 2022; 13:832144. [PMID: 35273627 PMCID: PMC8902505 DOI: 10.3389/fpls.2022.832144] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 01/20/2022] [Indexed: 05/19/2023]
Abstract
Protein N-acetyltransferases (NATs) belong to the general control non-repressible 5 (Gcn5)-related N-acetyltransferases (GNATs) superfamily. GNATs catalyze the transfer of acetyl from acetyl-CoA to the reactive amine moiety of a wide range of acceptors. NAT sequences are difficult to distinguish from other members of the GNAT superfamily and there are many uncharacterized GNATs. To facilitate the discovery and characterization of new GNATs, we have developed a new continuous, non-radioactive assay. This assay is virtually independent of the substrate and can be used to get substrate specificity hints. We validated first the assay with the well-characterized Schizosaccharomyces pombe NatA (SpNatA). The SpNatA kinetic parameters were determined with various peptides confirming the robustness of the new assay. We reveal that the longer the peptide substrate the more efficient the enzyme. As a proof of concept of the relevance of the new assay, we characterized a NAA90 member from rice (Oryza sativa), OsGNAT2. We took advantage of an in vivo medium-scale characterization of OsGNAT2 specificity to identify and then validate in vitro several specific peptide substrates. With this assay, we reveal long-range synergic effects of basic residues on OsGNAT2 activity. Overall, this new, high-throughput assay allows better understanding of the substrate specificity and activity of any GNAT.
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8
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Van Damme P. Charting the N-Terminal Acetylome: A Comprehensive Map of Human NatA Substrates. Int J Mol Sci 2021; 22:ijms221910692. [PMID: 34639033 PMCID: PMC8509067 DOI: 10.3390/ijms221910692] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/10/2021] [Accepted: 09/29/2021] [Indexed: 11/29/2022] Open
Abstract
N-terminal acetylation (Nt-acetylation) catalyzed by conserved N-terminal acetyltransferases or NATs embodies a modification with one of the highest stoichiometries reported for eukaryotic protein modifications to date. Comprising the catalytic N-alpha acetyltransferase (NAA) subunit NAA10 plus the ribosome anchoring regulatory subunit NAA15, NatA represents the major acetyltransferase complex with up to 50% of all mammalian proteins representing potential substrates. Largely in consequence of the essential nature of NatA and its high enzymatic activity, its experimentally confirmed mammalian substrate repertoire remained poorly charted. In this study, human NatA knockdown conditions achieving near complete depletion of NAA10 and NAA15 expression resulted in lowered Nt-acetylation of over 25% out of all putative NatA targets identified, representing an up to 10-fold increase in the reported number of substrate N-termini affected upon human NatA perturbation. Besides pointing to less efficient NatA substrates being prime targets, several putative NatE substrates were shown to be affected upon human NatA knockdown. Intriguingly, next to a lowered expression of ribosomal proteins and proteins constituting the eukaryotic 48S preinitiation complex, steady-state levels of protein N-termini additionally point to NatA Nt-acetylation deficiency directly impacting protein stability of knockdown affected targets.
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Affiliation(s)
- Petra Van Damme
- iRIP Unit, Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K. L. Ledeganckstraat 35, 9000 Ghent, Belgium
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9
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Reply to: Acetyl-CoA is produced by the citrate synthase homology module of ATP-citrate lyase. Nat Struct Mol Biol 2021; 28:639-641. [PMID: 34294921 DOI: 10.1038/s41594-021-00625-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 06/16/2021] [Indexed: 11/09/2022]
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10
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Deng S, Gottlieb L, Pan B, Supplee J, Wei X, Petersson EJ, Marmorstein R. Molecular mechanism of N-terminal acetylation by the ternary NatC complex. Structure 2021; 29:1094-1104.e4. [PMID: 34019809 DOI: 10.1016/j.str.2021.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/15/2021] [Accepted: 04/30/2021] [Indexed: 11/30/2022]
Abstract
Protein N-terminal acetylation is predominantly a ribosome-associated modification, with NatA-E serving as the major enzymes. NatC is the most unusual of these enzymes, containing one Naa30 catalytic subunit and two auxiliary subunits, Naa35 and Naa38; and substrate selectivity profile that overlaps with NatE. Here, we report the cryoelectron microscopy structure of S. pombe NatC with a NatE/C-type bisubstrate analog and inositol hexaphosphate (IP6), and associated biochemistry studies. We find that the presence of three subunits is a prerequisite for normal NatC acetylation activity in yeast and that IP6 binds tightly to NatC to stabilize the complex. We also describe the molecular basis for IP6-mediated NatC complex stabilization and the overlapping yet distinct substrate profiles of NatC and NatE.
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Affiliation(s)
- Sunbin Deng
- Department of Chemistry, 231 South 34(th) Street, University of Pennsylvania, Philadelphia, PA 19104, USA; Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Leah Gottlieb
- Department of Chemistry, 231 South 34(th) Street, University of Pennsylvania, Philadelphia, PA 19104, USA; Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Buyan Pan
- Department of Chemistry, 231 South 34(th) Street, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Julianna Supplee
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, 421 Curie Boulevard, Philadelphia, PA 19104, USA; Graduate Group in Biochemistry and Molecular Biophysics, Perelman School of Medicine, University of Pennsylvania, 421 Curie Boulevard, Philadelphia, PA 19104, USA
| | - Xuepeng Wei
- Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, 421 Curie Boulevard, Philadelphia, PA 19104, USA
| | - E James Petersson
- Department of Chemistry, 231 South 34(th) Street, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ronen Marmorstein
- Department of Chemistry, 231 South 34(th) Street, University of Pennsylvania, Philadelphia, PA 19104, USA; Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, 421 Curie Boulevard, Philadelphia, PA 19104, USA.
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11
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Krtenic B, Drazic A, Arnesen T, Reuter N. Classification and phylogeny for the annotation of novel eukaryotic GNAT acetyltransferases. PLoS Comput Biol 2020; 16:e1007988. [PMID: 33362253 PMCID: PMC7790372 DOI: 10.1371/journal.pcbi.1007988] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 01/07/2021] [Accepted: 10/16/2020] [Indexed: 11/19/2022] Open
Abstract
The enzymes of the GCN5-related N-acetyltransferase (GNAT) superfamily count more than 870 000 members through all kingdoms of life and share the same structural fold. GNAT enzymes transfer an acyl moiety from acyl coenzyme A to a wide range of substrates including aminoglycosides, serotonin, glucosamine-6-phosphate, protein N-termini and lysine residues of histones and other proteins. The GNAT subtype of protein N-terminal acetyltransferases (NATs) alone targets a majority of all eukaryotic proteins stressing the omnipresence of the GNAT enzymes. Despite the highly conserved GNAT fold, sequence similarity is quite low between members of this superfamily even when substrates are similar. Furthermore, this superfamily is phylogenetically not well characterized. Thus functional annotation based on sequence similarity is unreliable and strongly hampered for thousands of GNAT members that remain biochemically uncharacterized. Here we used sequence similarity networks to map the sequence space and propose a new classification for eukaryotic GNAT acetyltransferases. Using the new classification, we built a phylogenetic tree, representing the entire GNAT acetyltransferase superfamily. Our results show that protein NATs have evolved more than once on the GNAT acetylation scaffold. We use our classification to predict the function of uncharacterized sequences and verify by in vitro protein assays that two fungal genes encode NAT enzymes targeting specific protein N-terminal sequences, showing that even slight changes on the GNAT fold can lead to change in substrate specificity. In addition to providing a new map of the relationship between eukaryotic acetyltransferases the classification proposed constitutes a tool to improve functional annotation of GNAT acetyltransferases. Enzymes of the GCN5-related N-acetyltransferase (GNAT) superfamily transfer an acetyl group from one molecule to another. This reaction is called acetylation and is one of the most common reactions inside the cell. The GNAT superfamily counts more than 870 000 members through all kingdoms of life. Despite sharing the same fold the GNAT superfamily is very diverse in terms of amino acid sequence and substrates. The eight N-terminal acetyltransferases (NatA, NatB, etc.. to NatH) are a GNAT subtype which acetylates the free amine group of polypeptide chains. This modification is called N-terminal acetylation and is one of the most abundant protein modifications in eukaryotic cells. This subtype is also characterized by a high sequence diversity even though they share the same substrate. In addition, the phylogeny of the superfamily is not characterized. This hampers functional annotation based on sequence similarity, and discovery of novel NATs. In this work we set out to solve the problem of the classification of eukaryotic GCN5-related acetyltransferases and report the first classification framework of the superfamily. This framework can be used as a tool for annotation of all GCN5-related acetyltransferases. As an example of what can be achieved we report in this paper the computational prediction and in vitro verification of the function of two previously uncharacterized N-terminal acetyltransferases. We also report the first acetyltransferase phylogenetic tree of the GCN5 superfamily. It indicates that N-terminal acetyltransferases do not constitute one homogeneous protein family, but that the ability to bind and acetylate protein N-termini had evolved more than once on the same acetylation scaffold. We also show that even small changes in key positions can lead to altered enzyme specificity.
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Affiliation(s)
- Bojan Krtenic
- Department of Biological Sciences, University of Bergen, Norway
- Computational Biology Unit, Department of Informatics, University of Bergen, Norway
- * E-mail: (BK); (NR)
| | - Adrian Drazic
- Department of Biomedicine, University of Bergen, Norway
| | - Thomas Arnesen
- Department of Biological Sciences, University of Bergen, Norway
- Department of Biomedicine, University of Bergen, Norway
- Department of Surgery, Haukeland University Hospital, Norway
| | - Nathalie Reuter
- Computational Biology Unit, Department of Informatics, University of Bergen, Norway
- Department of Chemistry, University of Bergen, Norway
- * E-mail: (BK); (NR)
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12
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Grunwald S, Hopf LVM, Bock-Bierbaum T, Lally CCM, Spahn CMT, Daumke O. Divergent architecture of the heterotrimeric NatC complex explains N-terminal acetylation of cognate substrates. Nat Commun 2020; 11:5506. [PMID: 33139728 PMCID: PMC7608589 DOI: 10.1038/s41467-020-19321-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 10/06/2020] [Indexed: 02/07/2023] Open
Abstract
The heterotrimeric NatC complex, comprising the catalytic Naa30 and the two auxiliary subunits Naa35 and Naa38, co-translationally acetylates the N-termini of numerous eukaryotic target proteins. Despite its unique subunit composition, its essential role for many aspects of cellular function and its suggested involvement in disease, structure and mechanism of NatC have remained unknown. Here, we present the crystal structure of the Saccharomyces cerevisiae NatC complex, which exhibits a strikingly different architecture compared to previously described N-terminal acetyltransferase (NAT) complexes. Cofactor and ligand-bound structures reveal how the first four amino acids of cognate substrates are recognized at the Naa30–Naa35 interface. A sequence-specific, ligand-induced conformational change in Naa30 enables efficient acetylation. Based on detailed structure–function studies, we suggest a catalytic mechanism and identify a ribosome-binding patch in an elongated tip region of NatC. Our study reveals how NAT machineries have divergently evolved to N-terminally acetylate specific subsets of target proteins. The conserved eukaryotic heterotrimeric NatC complex co-translationally acetylates the N-termini of numerous target proteins. Here, the authors provide insights into the catalytic mechanism of NatC by determining the crystal structures of Saccharomyces cerevisiae NatC in the absence and presence of cofactors and peptide substrates and reveal the molecular basis of substrate binding by further biochemical analyses.
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Affiliation(s)
- Stephan Grunwald
- Department of Crystallography, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany.,Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195, Berlin, Germany
| | - Linus V M Hopf
- Department of Crystallography, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany.,Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195, Berlin, Germany
| | - Tobias Bock-Bierbaum
- Department of Crystallography, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany
| | - Ciara C M Lally
- Institute of Medical Physics and Biophysics, Charité - Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - Christian M T Spahn
- Institute of Medical Physics and Biophysics, Charité - Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - Oliver Daumke
- Department of Crystallography, Max Delbrück Center for Molecular Medicine, 13125, Berlin, Germany. .,Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195, Berlin, Germany.
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13
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Koufaris C, Kirmizis A. N-Terminal Acetyltransferases Are Cancer-Essential Genes Prevalently Upregulated in Tumours. Cancers (Basel) 2020; 12:E2631. [PMID: 32942614 PMCID: PMC7565035 DOI: 10.3390/cancers12092631] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/24/2020] [Accepted: 09/01/2020] [Indexed: 02/06/2023] Open
Abstract
N-terminal acetylation (Nt-Ac) is an abundant eukaryotic protein modification, deposited in humans by one of seven N-terminal acetyltransferase (NAT) complexes composed of a catalytic and potentially auxiliary subunits. The involvement of NATs in cancers is being increasingly recognised, but a systematic cross-tumour assessment is currently lacking. To address this limitation, we conducted here a multi-omic data interrogation for NATs. We found that tumour genomic alterations of NATs or of their protein substrates are generally rare events, with some tumour-specific exceptions. In contrast, altered gene expression of NATs in cancers and their association with patient survival constitute a widespread cancer phenomenon. Examination of dependency screens revealed that (i), besides NAA60 and NAA80 and the NatA paralogues NAA11 and NAA16, the other ten NAT genes were within the top 80th percentile of the most dependent genes (ii); NATs act through distinct biological processes. NAA40 (NatD) emerged as a NAT with particularly interesting cancer biology and therapeutic potential, especially in liver cancer where a novel oncogenic role was supported by its increased expression in multiple studies and its association with patient survival. In conclusion, this study generated insights and data that will be of great assistance in guiding further research into the function and therapeutic potential of NATs in cancer.
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Affiliation(s)
- Costas Koufaris
- Department of Biological Sciences, University of Cyprus, 1678 Nicosia, Cyprus
| | - Antonis Kirmizis
- Department of Biological Sciences, University of Cyprus, 1678 Nicosia, Cyprus
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14
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Protein N-Terminal Acetylation: Structural Basis, Mechanism, Versatility, and Regulation. Trends Biochem Sci 2020; 46:15-27. [PMID: 32912665 DOI: 10.1016/j.tibs.2020.08.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/03/2020] [Accepted: 08/06/2020] [Indexed: 12/15/2022]
Abstract
N-terminal acetylation (NTA) is one of the most widespread protein modifications, which occurs on most eukaryotic proteins, but is significantly less common on bacterial and archaea proteins. This modification is carried out by a family of enzymes called N-terminal acetyltransferases (NATs). To date, 12 NATs have been identified, harboring different composition, substrate specificity, and in some cases, modes of regulation. Recent structural and biochemical analysis of NAT proteins allows for a comparison of their molecular mechanisms and modes of regulation, which are described here. Although sharing an evolutionarily conserved fold and related catalytic mechanism, each catalytic subunit uses unique elements to mediate substrate-specific activity, and use NAT-type specific auxiliary and regulatory subunits, for their cellular functions.
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15
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Bienvenut WV, Brünje A, Boyer J, Mühlenbeck JS, Bernal G, Lassowskat I, Dian C, Linster E, Dinh TV, Koskela MM, Jung V, Seidel J, Schyrba LK, Ivanauskaite A, Eirich J, Hell R, Schwarzer D, Mulo P, Wirtz M, Meinnel T, Giglione C, Finkemeier I. Dual lysine and N-terminal acetyltransferases reveal the complexity underpinning protein acetylation. Mol Syst Biol 2020; 16:e9464. [PMID: 32633465 PMCID: PMC7339202 DOI: 10.15252/msb.20209464] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 01/02/2023] Open
Abstract
Protein acetylation is a highly frequent protein modification. However, comparatively little is known about its enzymatic machinery. N-α-acetylation (NTA) and ε-lysine acetylation (KA) are known to be catalyzed by distinct families of enzymes (NATs and KATs, respectively), although the possibility that the same GCN5-related N-acetyltransferase (GNAT) can perform both functions has been debated. Here, we discovered a new family of plastid-localized GNATs, which possess a dual specificity. All characterized GNAT family members display a number of unique features. Quantitative mass spectrometry analyses revealed that these enzymes exhibit both distinct KA and relaxed NTA specificities. Furthermore, inactivation of GNAT2 leads to significant NTA or KA decreases of several plastid proteins, while proteins of other compartments were unaffected. The data indicate that these enzymes have specific protein targets and likely display partly redundant selectivity, increasing the robustness of the acetylation process in vivo. In summary, this study revealed a new layer of complexity in the machinery controlling this prevalent modification and suggests that other eukaryotic GNATs may also possess these previously underappreciated broader enzymatic activities.
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Affiliation(s)
- Willy V Bienvenut
- Université Paris‐SaclayCEACNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance
- Present address:
Génétique Quantitative et ÉvolutionGif‐sur‐YvetteFrance
| | - Annika Brünje
- Plant PhysiologyInstitute of Plant Biology and BiotechnologyUniversity of MuensterMuensterGermany
| | - Jean‐Baptiste Boyer
- Université Paris‐SaclayCEACNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance
| | - Jens S Mühlenbeck
- Plant PhysiologyInstitute of Plant Biology and BiotechnologyUniversity of MuensterMuensterGermany
| | - Gautier Bernal
- Université Paris‐SaclayCEACNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance
- Present address:
Institute of Plant Sciences Paris‐SaclayGif‐sur‐YvetteFrance
| | - Ines Lassowskat
- Plant PhysiologyInstitute of Plant Biology and BiotechnologyUniversity of MuensterMuensterGermany
| | - Cyril Dian
- Université Paris‐SaclayCEACNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance
| | - Eric Linster
- Centre for Organismal Studies HeidelbergUniversity of HeidelbergHeidelbergGermany
| | - Trinh V Dinh
- Centre for Organismal Studies HeidelbergUniversity of HeidelbergHeidelbergGermany
| | - Minna M Koskela
- Department of BiochemistryMolecular Plant BiologyUniversity of TurkuTurkuFinland
- Present address:
Institute of MicrobiologyTřeboňCzech Republic
| | - Vincent Jung
- Université Paris‐SaclayCEACNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance
- Present address:
Institute IMAGINEParisFrance
| | - Julian Seidel
- Interfaculty Institute of BiochemistryUniversity of TübingenTübingenGermany
| | - Laura K Schyrba
- Plant PhysiologyInstitute of Plant Biology and BiotechnologyUniversity of MuensterMuensterGermany
| | - Aiste Ivanauskaite
- Department of BiochemistryMolecular Plant BiologyUniversity of TurkuTurkuFinland
| | - Jürgen Eirich
- Plant PhysiologyInstitute of Plant Biology and BiotechnologyUniversity of MuensterMuensterGermany
| | - Rüdiger Hell
- Centre for Organismal Studies HeidelbergUniversity of HeidelbergHeidelbergGermany
| | - Dirk Schwarzer
- Interfaculty Institute of BiochemistryUniversity of TübingenTübingenGermany
| | - Paula Mulo
- Department of BiochemistryMolecular Plant BiologyUniversity of TurkuTurkuFinland
| | - Markus Wirtz
- Centre for Organismal Studies HeidelbergUniversity of HeidelbergHeidelbergGermany
| | - Thierry Meinnel
- Université Paris‐SaclayCEACNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance
| | - Carmela Giglione
- Université Paris‐SaclayCEACNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance
| | - Iris Finkemeier
- Plant PhysiologyInstitute of Plant Biology and BiotechnologyUniversity of MuensterMuensterGermany
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16
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Lapteva YS, Vologzhannikova AA, Sokolov AS, Ismailov RG, Uversky VN, Permyakov SE. In Vitro N-Terminal Acetylation of Bacterially Expressed Parvalbumins by N-Terminal Acetyltransferases from Escherichia coli. Appl Biochem Biotechnol 2020; 193:1365-1378. [PMID: 32394317 DOI: 10.1007/s12010-020-03324-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/23/2020] [Indexed: 11/28/2022]
Abstract
Most eukaryotic proteins are N-terminally acetylated (Nt-acetylated) by specific N-terminal acetyltransferases (NATs). Although this co-/post-translational protein modification may affect different aspects of protein functioning, it is typically neglected in studies of bacterially expressed eukaryotic proteins, lacking this modification. To overcome this limitation of bacterial expression, we have probed the efficiency of recombinant Escherichia coli NATs (RimI, RimJ, and RimL) with regard to in vitro Nt-acetylation of several parvalbumins (PAs) expressed in E. coli. PA is a calcium-binding protein of vertebrates, which is sensitive to Nt-acetylation. Our analyses revealed that only metal-free PAs were prone to Nt-acetylation (up to 100%), whereas Ca2+ binding abolished this modification, thereby indicating that Ca2+-induced structural stabilization of PAs impedes their Nt-acetylation. RimJ and RimL were active towards all PAs with N-terminal serine. Their activity towards PAs beginning with alanine was PA-specific, suggesting the importance of the subsequent residues. RimI showed the least activity regardless of the PA studied. Overall, NATs from E. coli are suited for post-translational Nt-acetylation of bacterially expressed eukaryotic proteins with decreased structural stability.
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Affiliation(s)
- Yulia S Lapteva
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, 142290, Russia.
| | - Alisa A Vologzhannikova
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, 142290, Russia
| | - Andrey S Sokolov
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, 142290, Russia
| | - Ramis G Ismailov
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, 142290, Russia
| | - Vladimir N Uversky
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, 142290, Russia. .,Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.
| | - Sergei E Permyakov
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, 142290, Russia
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17
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Abboud A, Bédoucha P, Byška J, Arnesen T, Reuter N. Dynamics-function relationship in the catalytic domains of N-terminal acetyltransferases. Comput Struct Biotechnol J 2020; 18:532-547. [PMID: 32206212 PMCID: PMC7078549 DOI: 10.1016/j.csbj.2020.02.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/14/2020] [Accepted: 02/25/2020] [Indexed: 12/15/2022] Open
Abstract
N-terminal acetyltransferases (NATs) belong to the superfamily of acetyltransferases. They are enzymes catalysing the transfer of an acetyl group from acetyl coenzyme A to the N-terminus of polypeptide chains. N-terminal acetylation is one of the most common protein modifications. To date, not much is known on the molecular basis for the exclusive substrate specificity of NATs. All NATs share a common fold called GNAT. A characteristic of NATs is the β6β7 hairpin loop covering the active site and forming with the α1α2 loop a narrow tunnel surrounding the catalytic site in which cofactor and polypeptide meet and exchange an acetyl group. We investigated the dynamics-function relationships of all available structures of NATs covering the three domains of Life. Using an elastic network model and normal mode analysis, we found a common dynamics pattern conserved through the GNAT fold; a rigid V-shaped groove formed by the β4 and β5 strands and splitting the fold in two dynamical subdomains. Loops α1α2, β3β4 and β6β7 all show clear displacements in the low frequency normal modes. We characterized the mobility of the loops and show that even limited conformational changes of the loops along the low-frequency modes are able to significantly change the size and shape of the ligand binding sites. Based on the fact that these movements are present in most low-frequency modes, and common to all NATs, we suggest that the α1α2 and β6β7 loops may regulate ligand uptake and the release of the acetylated polypeptide.
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Affiliation(s)
- Angèle Abboud
- Department of Informatics, University of Bergen, Bergen, Norway
- Computational Biology Unit, Department of Informatics, University of Bergen, Bergen, Norway
| | - Pierre Bédoucha
- Department of Informatics, University of Bergen, Bergen, Norway
- Computational Biology Unit, Department of Informatics, University of Bergen, Bergen, Norway
| | - Jan Byška
- Department of Informatics, University of Bergen, Bergen, Norway
- Faculty of Informatics, Masaryk University, Brno, Czech Republic
| | - Thomas Arnesen
- Department of Biological Sciences, University of Bergen, Bergen, Norway
- Department of Biomedicine, University of Bergen, Bergen, Norway
- Department of Surgery, Haukeland University Hospital, Bergen, Norway
| | - Nathalie Reuter
- Computational Biology Unit, Department of Informatics, University of Bergen, Bergen, Norway
- Department of Chemistry, University of Bergen, Bergen, Norway
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18
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Huber M, Bienvenut WV, Linster E, Stephan I, Armbruster L, Sticht C, Layer D, Lapouge K, Meinnel T, Sinning I, Giglione C, Hell R, Wirtz M. NatB-Mediated N-Terminal Acetylation Affects Growth and Biotic Stress Responses. PLANT PHYSIOLOGY 2020; 182:792-806. [PMID: 31744933 PMCID: PMC6997699 DOI: 10.1104/pp.19.00792] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 11/07/2019] [Indexed: 05/22/2023]
Abstract
N∝-terminal acetylation (NTA) is one of the most abundant protein modifications in eukaryotes. In humans, NTA is catalyzed by seven Nα-acetyltransferases (NatA-F and NatH). Remarkably, the plant Nat machinery and its biological relevance remain poorly understood, although NTA has gained recognition as a key regulator of crucial processes such as protein turnover, protein-protein interaction, and protein targeting. In this study, we combined in vitro assays, reverse genetics, quantitative N-terminomics, transcriptomics, and physiological assays to characterize the Arabidopsis (Arabidopsis thaliana) NatB complex. We show that the plant NatB catalytic (NAA20) and auxiliary subunit (NAA25) form a stable heterodimeric complex that accepts canonical NatB-type substrates in vitro. In planta, NatB complex formation was essential for enzymatic activity. Depletion of NatB subunits to 30% of the wild-type level in three Arabidopsis T-DNA insertion mutants (naa20-1, naa20-2, and naa25-1) caused a 50% decrease in plant growth. A complementation approach revealed functional conservation between plant and human catalytic NatB subunits, whereas yeast NAA20 failed to complement naa20-1 Quantitative N-terminomics of approximately 1000 peptides identified 32 bona fide substrates of the plant NatB complex. In vivo, NatB was seen to preferentially acetylate N termini starting with the initiator Met followed by acidic amino acids and contributed 20% of the acetylation marks in the detected plant proteome. Global transcriptome and proteome analyses of NatB-depleted mutants suggested a function of NatB in multiple stress responses. Indeed, loss of NatB function, but not NatA, increased plant sensitivity toward osmotic and high-salt stress, indicating that NatB is required for tolerance of these abiotic stressors.
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Affiliation(s)
- Monika Huber
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Willy V Bienvenut
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Eric Linster
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Iwona Stephan
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Laura Armbruster
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | | | - Dominik Layer
- Heidelberg University Biochemistry Center, 69120 Heidelberg, Germany
| | - Karine Lapouge
- Heidelberg University Biochemistry Center, 69120 Heidelberg, Germany
| | - Thierry Meinnel
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Irmgard Sinning
- Heidelberg University Biochemistry Center, 69120 Heidelberg, Germany
| | - Carmela Giglione
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Ruediger Hell
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Markus Wirtz
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
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19
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Gottlieb L, Marmorstein R. Biochemical and structural analysis of N-terminal acetyltransferases. Methods Enzymol 2019; 626:271-299. [PMID: 31606079 DOI: 10.1016/bs.mie.2019.07.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
N-terminal acetylation is a co- and post-translational modification catalyzed by the conserved N-terminal acetyltransferase (NAT) family of enzymes. A majority of the human proteome is modified by the human NATs (NatA-F and H), which are minimally composed of a catalytic subunit and as many as two auxiliary subunits. Together, NATs specifically regulate many cellular functions by influencing protein activities such as their degradation, membrane targeting, and protein-protein interactions. This chapter will describe methods developed for their preparation, and their biochemical and structural characterization. This will include methodologies for expression and purification of recombinant NAT protein, kinetic assays, biochemical and biophysical assays, and strategies for structural studies.
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Affiliation(s)
- Leah Gottlieb
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, United States; Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ronen Marmorstein
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, United States; Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
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20
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Cao J, Wang T, Wang Q, Zheng X, Huang L. Functional Insights Into Protein Acetylation in the Hyperthermophilic Archaeon Sulfolobus islandicus. Mol Cell Proteomics 2019; 18:1572-1587. [PMID: 31182439 PMCID: PMC6683002 DOI: 10.1074/mcp.ra119.001312] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 05/02/2019] [Indexed: 01/03/2023] Open
Abstract
Proteins undergo acetylation at the Nε-amino group of lysine residues and the Nα-amino group of the N terminus in Archaea as in Bacteria and Eukarya. However, the extent, pattern and roles of the modifications in Archaea remain poorly understood. Here we report the proteomic analyses of a wild-type Sulfolobus islandicus strain and its mutant derivative strains lacking either a homolog of the protein acetyltransferase Pat (ΔSisPat) or a homolog of the Nt-acetyltransferase Ard1 (ΔSisArd1). A total of 1708 Nε-acetylated lysine residues in 684 proteins (26% of the total proteins), and 158 Nt-acetylated proteins (44% of the identified proteins) were found in S. islandicus ΔSisArd1 grew more slowly than the parental strain, whereas ΔSisPat showed no significant growth defects. Only 24 out of the 1503 quantifiable Nε-acetylated lysine residues were differentially acetylated, and all but one of the 24 residues were less acetylated by >1.3 fold in ΔSisPat than in the parental strain, indicating the narrow substrate specificity of the enzyme. Six acyl-CoA synthetases were the preferred substrates of SisPat in vivo, suggesting that Nε-acetylation by the acetyltransferase is involved in maintaining metabolic balance in the cell. Acetylation of acyl-CoA synthetases by SisPat occurred at a sequence motif conserved among all three domains of life. On the other hand, 92% of the acetylated N termini identified were acetylated by SisArd1 in the cell. The enzyme exhibited broad substrate specificity and could modify nearly all types of the target N termini of human NatA-NatF. The deletion of the SisArd1 gene altered the cellular levels of 18% of the quantifiable proteins (1518) by >1.5 fold. Consistent with the growth phenotype of ΔSisArd1, the cellular levels of proteins involved in cell division and cell cycle control, DNA replication, and purine synthesis were significantly lowered in the mutant than those in the parental strain.
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Affiliation(s)
- Jingjing Cao
- ‡State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China; §College of Life Science, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Tongkun Wang
- ‡State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China; §College of Life Science, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Qian Wang
- ¶Core Facility of Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China
| | - Xiaowei Zheng
- ‡State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China; §College of Life Science, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Li Huang
- ‡State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China; §College of Life Science, University of Chinese Academy of Sciences, Beijing, P. R. China.
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21
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Structural determinants and cellular environment define processed actin as the sole substrate of the N-terminal acetyltransferase NAA80. Proc Natl Acad Sci U S A 2018; 115:4405-4410. [PMID: 29581307 PMCID: PMC5924903 DOI: 10.1073/pnas.1719251115] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
N-terminal acetylation performed by N-terminal acetyltransferases (NATs) is a common protein modification in human cells. A unique NAT, NAA80, was recently found to control actin N-terminal acetylation and cytoskeletal dynamics. In this study, we developed potent and specific bisubstrate inhibitors against NAA80 and determined the crystal structure of NAA80 in complex with an inhibitor mimicking the β-actin N terminus, thus revealing molecular determinants for the substrate specificity and selective inhibition of NAA80. A yeast model uncovered how a cellular determinant, the NatB enzyme, acts to restrict the number of in vivo NAA80 substrates relative to the broader intrinsic capacity of NAA80. Our data provide a starting point for further development of inhibitors for the regulation of actin and cytoskeletal functions. N-terminal (Nt) acetylation is a major protein modification catalyzed by N-terminal acetyltransferases (NATs). Methionine acidic N termini, including actin, are cotranslationally Nt acetylated by NatB in all eukaryotes, but animal actins containing acidic N termini, are additionally posttranslationally Nt acetylated by NAA80. Actin Nt acetylation was found to regulate cytoskeletal dynamics and motility, thus making NAA80 a potential target for cell migration regulation. In this work, we developed potent and selective bisubstrate inhibitors for NAA80 and determined the crystal structure of NAA80 in complex with such an inhibitor, revealing that NAA80 adopts a fold similar to other NAT enzymes but with a more open substrate binding region. Furthermore, in contrast to most other NATs, the substrate specificity of NAA80 is mainly derived through interactions between the enzyme and the acidic amino acids at positions 2 and 3 of the actin substrate and not residues 1 and 2. A yeast model revealed that ectopic expression of NAA80 in a strain lacking NatB activity partially restored Nt acetylation of NatB substrates, including yeast actin. Thus, NAA80 holds intrinsic capacity to posttranslationally Nt acetylate NatB-type substrates in vivo. In sum, the presence of a dominant cotranslational NatB in all eukaryotes, the specific posttranslational actin methionine removal in animals, and finally, the unique structural features of NAA80 leave only the processed actins as in vivo substrates of NAA80. Together, this study reveals the molecular and cellular basis of NAA80 Nt acetylation and provides a scaffold for development of inhibitors for the regulation of cytoskeletal properties.
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22
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Crystal structure of l -glutamate N -acetyltransferase ArgA from Mycobacterium tuberculosis. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:1800-1807. [DOI: 10.1016/j.bbapap.2017.09.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/18/2017] [Accepted: 09/20/2017] [Indexed: 11/22/2022]
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23
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Hong H, Cai Y, Zhang S, Ding H, Wang H, Han A. Molecular Basis of Substrate Specific Acetylation by N-Terminal Acetyltransferase NatB. Structure 2017; 25:641-649.e3. [PMID: 28380339 DOI: 10.1016/j.str.2017.03.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 01/24/2017] [Accepted: 03/09/2017] [Indexed: 11/29/2022]
Abstract
The NatB N-terminal acetyltransferase specifically acetylates the N-terminal group of substrate protein peptides starting with Met-Asp/Glu/Asn/Gln. How NatB recognizes and acetylates these substrates remains unknown. Here, we report crystal structures of a NatB holoenzyme from Candida albicans in the presence of its co-factor CoA and substrate peptides. The auxiliary subunit Naa25 of NatB forms a horseshoe-like deck to hold specifically its catalytic subunit Naa20. The first two amino acids Met and Asp of a substrate peptide mediate the major interactions with the active site in the Naa20 subunit. The hydrogen bonds between the substrate Asp and pocket residues of Naa20 are essential to determine the NatB substrate specificity. Moreover, a hydrogen bond between the amino group of the substrate Met and a carbonyl group in the Naa20 active site directly anchors the substrate toward acetyl-CoA. Together, these structures define a unique molecular mechanism of specific N-terminal acetylation acted by NatB.
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Affiliation(s)
- Haiyan Hong
- State Key Laboratory for Cellular Stress Biology, Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiang'an, Xiamen 361102, China
| | - Yongfei Cai
- State Key Laboratory for Cellular Stress Biology, Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiang'an, Xiamen 361102, China
| | - Shijun Zhang
- State Key Laboratory for Cellular Stress Biology, Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiang'an, Xiamen 361102, China
| | - Hongyan Ding
- State Key Laboratory for Cellular Stress Biology, Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiang'an, Xiamen 361102, China
| | - Haitao Wang
- Faculty of Health Sciences, University of Macau, Macau, China
| | - Aidong Han
- State Key Laboratory for Cellular Stress Biology, Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiang'an, Xiamen 361102, China.
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24
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Shin S, Choe J. Crystal structure of Pseudomonas aeruginosa N-acetyltransferase PA4534. Biochem Biophys Res Commun 2017; 487:236-240. [PMID: 28412357 DOI: 10.1016/j.bbrc.2017.04.040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 04/10/2017] [Indexed: 11/29/2022]
Abstract
The GCN5-related N-acetyltransferase (GNAT) superfamily includes a large and diverse group of enzymes that catalyzes the transfer of an acetyl group from acetyl coenzyme A (Ac-CoA) to the amine group of a substrate. Substrates include protein N-terminus, lysine of histone tails, and other small molecules such as aminoglycoside, serotonin, and glucose-6-phosphate. GNAT superfamily of proteins is involved in many physiologically important reactions in eukaryotes and prokaryotes. However, functions of many GNATs remain unknown and PA4534 is one of those uncharacterized GNAT proteins from Pseudomonas aeruginosa. To investigate functions of the PA4534, we determined the apo and Ac-CoA bound PA4534 structures. Our structures showed that PA4534 shared common characteristic structures with other GNAT family N-acetyltransferases and contained a potential substrate binding tunnel close to the bound Ac-CoA.
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Affiliation(s)
- Sungwook Shin
- Department of Life Science, University of Seoul, Seoul 130-743, South Korea
| | - Jungwoo Choe
- Department of Life Science, University of Seoul, Seoul 130-743, South Korea.
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25
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Bienvenut WV, Giglione C, Meinnel T. SILProNAQ: A Convenient Approach for Proteome-Wide Analysis of Protein N-Termini and N-Terminal Acetylation Quantitation. Methods Mol Biol 2017; 1574:17-34. [PMID: 28315241 DOI: 10.1007/978-1-4939-6850-3_3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Protein N-terminal modifications have recently been involved in overall proteostasis through their impact on cell fate and protein life time. This explains the development of new approaches to characterize more precisely the N-terminal end of mature proteins. Although few approaches are available to perform N-terminal enrichment based on positive or negative discriminations, these methods are usually restricted to the enrichment in N-terminal peptides and their characterization by mass spectrometry. Recent investigation highlights both (1) the knowledge of the N-terminal acetylation status of most cytosolic proteins and (2) post-translational addition of this modification on the N-terminus of nuclear coded chloroplast proteins imported in the plastid and after the cleavage of the transit peptide. The workflow involves stable isotope labeling to assess N-acetylation rates followed by Strong Cation eXchange (SCX ) fractionation of the samples to provide protein N-terminal enriched fractions. Combined with mass spectrometry analyses, the technology finally requires extensive data processing. This last step aims first at discriminating the most relevant mature N-termini from the characterized peptides, next at determining its experimental position and then at calculating the N-terminal acetylation yield. Stable-Isotope Protein N-terminal Acetylation Quantification (SILProNAQ) is a complete workflow combining wet-lab techniques together with dry-lab processing to determine the N-terminal acetylation yield of mature proteins for a clearly defined localization.
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Affiliation(s)
- Willy V Bienvenut
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris Saclay, Bâtiment 21, Avenue de la Terrassee, 91198, Gif-sur-Yvette cedex, France.
| | - Carmela Giglione
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris Saclay, Bâtiment 21, Avenue de la Terrassee, 91198, Gif-sur-Yvette cedex, France
| | - Thierry Meinnel
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris Saclay, Bâtiment 21, Avenue de la Terrassee, 91198, Gif-sur-Yvette cedex, France
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26
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Structure and function of human Naa60 (NatF), a Golgi-localized bi-functional acetyltransferase. Sci Rep 2016; 6:31425. [PMID: 27550639 PMCID: PMC4993997 DOI: 10.1038/srep31425] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 07/20/2016] [Indexed: 11/08/2022] Open
Abstract
N-terminal acetylation (Nt-acetylation), carried out by N-terminal acetyltransferases (NATs), is a conserved and primary modification of nascent peptide chains. Naa60 (also named NatF) is a recently identified NAT found only in multicellular eukaryotes. This protein was shown to locate on the Golgi apparatus and mainly catalyze the Nt-acetylation of transmembrane proteins, and it also harbors lysine Nε-acetyltransferase (KAT) activity to catalyze the acetylation of lysine ε-amine. Here, we report the crystal structures of human Naa60 (hNaa60) in complex with Acetyl-Coenzyme A (Ac-CoA) or Coenzyme A (CoA). The hNaa60 protein contains an amphipathic helix following its GNAT domain that may contribute to Golgi localization of hNaa60, and the β7-β8 hairpin adopted different conformations in the hNaa60(1-242) and hNaa60(1-199) crystal structures. Remarkably, we found that the side-chain of Phe 34 can influence the position of the coenzyme, indicating a new regulatory mechanism involving enzyme, co-factor and substrates interactions. Moreover, structural comparison and biochemical studies indicated that Tyr 97 and His 138 are key residues for catalytic reaction and that a non-conserved β3-β4 long loop participates in the regulation of hNaa60 activity.
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27
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Aksnes H, Drazic A, Marie M, Arnesen T. First Things First: Vital Protein Marks by N-Terminal Acetyltransferases. Trends Biochem Sci 2016; 41:746-760. [PMID: 27498224 DOI: 10.1016/j.tibs.2016.07.005] [Citation(s) in RCA: 172] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 07/01/2016] [Accepted: 07/08/2016] [Indexed: 11/28/2022]
Abstract
N-terminal (Nt) acetylation is known to be a highly abundant co-translational protein modification, but the recent discovery of Golgi- and chloroplast-resident N-terminal acetyltransferases (NATs) revealed that it can also be added post-translationally. Nt-acetylation may act as a degradation signal in a novel branch of the N-end rule pathway, whose functions include the regulation of human blood pressure. Nt-acetylation also modulates protein interactions, targeting, and folding. In plants, Nt-acetylation plays a role in the control of resistance to drought and in regulation of immune responses. Mutations of specific human NATs that decrease their activity can cause either the lethal Ogden syndrome or severe intellectual disability and cardiovascular defects. In sum, recent advances highlight Nt-acetylation as a key factor in many biological pathways.
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Affiliation(s)
- Henriette Aksnes
- Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway
| | - Adrian Drazic
- Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway
| | - Michaël Marie
- Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway
| | - Thomas Arnesen
- Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway; Department of Surgery, Haukeland University Hospital, 5021 Bergen, Norway.
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28
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Støve SI, Magin RS, Foyn H, Haug BE, Marmorstein R, Arnesen T. Crystal Structure of the Golgi-Associated Human Nα-Acetyltransferase 60 Reveals the Molecular Determinants for Substrate-Specific Acetylation. Structure 2016; 24:1044-56. [PMID: 27320834 DOI: 10.1016/j.str.2016.04.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 04/22/2016] [Accepted: 04/26/2016] [Indexed: 01/17/2023]
Abstract
N-Terminal acetylation is a common and important protein modification catalyzed by N-terminal acetyltransferases (NATs). Six human NATs (NatA-NatF) contain one catalytic subunit each, Naa10 to Naa60, respectively. In contrast to the ribosome-associated NatA to NatE, NatF/Naa60 specifically associates with Golgi membranes and acetylates transmembrane proteins. To gain insight into the molecular basis for the function of Naa60, we developed an Naa60 bisubstrate CoA-peptide conjugate inhibitor, determined its X-ray structure when bound to CoA and inhibitor, and carried out biochemical experiments. We show that Naa60 adapts an overall fold similar to that of the catalytic subunits of ribosome-associated NATs, but with the addition of two novel elongated loops that play important roles in substrate-specific binding. One of these loops mediates a dimer to monomer transition upon substrate-specific binding. Naa60 employs a catalytic mechanism most similar to Naa50. Collectively, these data reveal the molecular basis for Naa60-specific acetyltransferase activity with implications for its Golgi-specific functions.
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Affiliation(s)
- Svein Isungset Støve
- Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway; Department of Surgery, Haukeland University Hospital, 5021 Bergen, Norway
| | - Robert S Magin
- Department of Biochemistry and Biophysics, Abramson Family Cancer Research Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Graduate Group in Biochemistry and Molecular Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Program in Gene Expression and Regulation, Wistar Institute, Philadelphia, PA 19104, USA
| | - Håvard Foyn
- Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway
| | - Bengt Erik Haug
- Department of Chemistry, University of Bergen, 5020 Bergen, Norway
| | - Ronen Marmorstein
- Department of Biochemistry and Biophysics, Abramson Family Cancer Research Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Graduate Group in Biochemistry and Molecular Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Program in Gene Expression and Regulation, Wistar Institute, Philadelphia, PA 19104, USA.
| | - Thomas Arnesen
- Department of Molecular Biology, University of Bergen, 5020 Bergen, Norway; Department of Surgery, Haukeland University Hospital, 5021 Bergen, Norway.
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29
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Rathore OS, Faustino A, Prudêncio P, Van Damme P, Cox CJ, Martinho RG. Absence of N-terminal acetyltransferase diversification during evolution of eukaryotic organisms. Sci Rep 2016; 6:21304. [PMID: 26861501 PMCID: PMC4748286 DOI: 10.1038/srep21304] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 01/18/2016] [Indexed: 11/09/2022] Open
Abstract
Protein N-terminal acetylation is an ancient and ubiquitous co-translational modification catalyzed by a highly conserved family of N-terminal acetyltransferases (NATs). Prokaryotes have at least 3 NATs, whereas humans have six distinct but highly conserved NATs, suggesting an increase in regulatory complexity of this modification during eukaryotic evolution. Despite this, and against our initial expectations, we determined that NAT diversification did not occur in the eukaryotes, as all six major human NATs were most likely present in the Last Eukaryotic Common Ancestor (LECA). Furthermore, we also observed that some NATs were actually secondarily lost during evolution of major eukaryotic lineages; therefore, the increased complexity of the higher eukaryotic proteome occurred without a concomitant diversification of NAT complexes.
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Affiliation(s)
- Om Singh Rathore
- Department of Biomedical Sciences and Medicine, Faro, Portugal.,Center for Biomedical Research (CBMR), Faro, Portugal.,ProRegeM-PhD Program in Mechanisms of Disease and Regenerative Medicine, Faro, Portugal
| | - Alexandra Faustino
- Department of Biomedical Sciences and Medicine, Faro, Portugal.,Center for Biomedical Research (CBMR), Faro, Portugal
| | - Pedro Prudêncio
- Department of Biomedical Sciences and Medicine, Faro, Portugal.,Center for Biomedical Research (CBMR), Faro, Portugal.,Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras 2781-901, Portugal
| | - Petra Van Damme
- Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium.,Department of Biochemistry, Ghent University, B-9000 Ghent, Belgium
| | - Cymon J Cox
- Center of Marine Sciences, University of Algarve, Faro, Portugal
| | - Rui Gonçalo Martinho
- Department of Biomedical Sciences and Medicine, Faro, Portugal.,Center for Biomedical Research (CBMR), Faro, Portugal.,Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Oeiras 2781-901, Portugal
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30
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Magin RS, March ZM, Marmorstein R. The N-terminal Acetyltransferase Naa10/ARD1 Does Not Acetylate Lysine Residues. J Biol Chem 2016; 291:5270-7. [PMID: 26755727 DOI: 10.1074/jbc.m115.709428] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Indexed: 11/06/2022] Open
Abstract
The N-terminal acetyltransferase NatA is a heterodimeric complex consisting of a catalytic subunit (Naa10/ARD1) and an auxiliary subunit (Naa15). NatA co-translationally acetylates the N termini of a wide variety of nascent polypeptides. In addition, Naa10 can act independently to posttranslationally acetylate a distinct set of substrates, notably actin. Recent structural studies of Naa10 have also revealed the molecular basis for N-terminal acetylation specificity. Surprisingly, recent reports claim that Naa10 may also acetylate lysine residues of diverse targets, including methionine sulfoxide reductase A, myosin light chain kinase, and Runt-related transcription factor 2. Here we used recombinant proteins to reconstitute and assess lysine acetylation events catalyzed by Naa10 in vitro. We show that there is no difference in lysine acetylation of substrate proteins with or without Naa10, suggesting that the substrates may be acetylated chemically rather than enzymatically. Together, our data argue against a role for Naa10 in lysine acetylation.
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Affiliation(s)
- Robert S Magin
- From the Department of Biochemistry and Biophysics, Abramson Family Cancer Research Institute, and Graduate Group in Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 and
| | - Zachary M March
- From the Department of Biochemistry and Biophysics, Graduate Group in Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 and
| | - Ronen Marmorstein
- From the Department of Biochemistry and Biophysics, Abramson Family Cancer Research Institute, and the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
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31
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Giglione C, Fieulaine S, Meinnel T. N-terminal protein modifications: Bringing back into play the ribosome. Biochimie 2015; 114:134-46. [PMID: 25450248 DOI: 10.1016/j.biochi.2014.11.008] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 11/10/2014] [Indexed: 10/24/2022]
Abstract
N-terminal protein modifications correspond to the first modifications which in principle any protein may undergo, before translation is completed by the ribosome. This class of essential modifications can have different nature or function and be catalyzed by a variety of dedicated enzymes. Here, we review the current state of the major N-terminal co-translational modifications, with a particular emphasis to their catalysts, which belong to metalloprotease and acyltransferase clans. The earliest of these modifications corresponds to the N-terminal methionine excision, an ubiquitous and essential process leading to the removal of the first methionine. N-alpha acetylation occurs also in all Kingdoms although its extent appears to be significantly increased in higher eukaryotes. Finally, N-myristoylation is a crucial pathway existing only in eukaryotes. Recent studies dealing on how some of these co-translational modifiers might work in close vicinity of the ribosome is starting to provide new information on when these modifications exactly take place on the elongating nascent chain and the interplay with other ribosome biogenesis factors taking in charge the nascent chains. Here a comprehensive overview of the recent advances in the field of N-terminal protein modifications is given.
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Affiliation(s)
- Carmela Giglione
- CNRS, Institut des Sciences du Végétal, 1 Avenue de la Terrasse, Bât 23A, F-91198 Gif sur Yvette, France; Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette cedex, France.
| | - Sonia Fieulaine
- CNRS, Institut des Sciences du Végétal, 1 Avenue de la Terrasse, Bât 23A, F-91198 Gif sur Yvette, France; Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette cedex, France
| | - Thierry Meinnel
- CNRS, Institut des Sciences du Végétal, 1 Avenue de la Terrasse, Bât 23A, F-91198 Gif sur Yvette, France; Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette cedex, France.
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32
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Dinh TV, Bienvenut WV, Linster E, Feldman-Salit A, Jung VA, Meinnel T, Hell R, Giglione C, Wirtz M. Molecular identification and functional characterization of the first Nα-acetyltransferase in plastids by global acetylome profiling. Proteomics 2015; 15:2426-35. [PMID: 25951519 PMCID: PMC4692087 DOI: 10.1002/pmic.201500025] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 03/20/2015] [Accepted: 04/30/2015] [Indexed: 11/07/2022]
Abstract
Protein N(α) -terminal acetylation represents one of the most abundant protein modifications of higher eukaryotes. In humans, six N(α) -acetyltransferases (Nats) are responsible for the acetylation of approximately 80% of the cytosolic proteins. N-terminal protein acetylation has not been evidenced in organelles of metazoans, but in higher plants is a widespread modification not only in the cytosol but also in the chloroplast. In this study, we identify and characterize the first organellar-localized Nat in eukaryotes. A primary sequence-based search in Arabidopsis thaliana revealed seven putatively plastid-localized Nats of which AT2G39000 (AtNAA70) showed the highest conservation of the acetyl-CoA binding pocket. The chloroplastic localization of AtNAA70 was demonstrated by transient expression of AtNAA70:YFP in Arabidopsis mesophyll protoplasts. Homology modeling uncovered a significant conservation of tertiary structural elements between human HsNAA50 and AtNAA70. The in vivo acetylation activity of AtNAA70 was demonstrated on a number of distinct protein N(α) -termini with a newly established global acetylome profiling test after expression of AtNAA70 in E. coli. AtNAA70 predominately acetylated proteins starting with M, A, S and T, providing an explanation for most protein N-termini acetylation events found in chloroplasts. Like HsNAA50, AtNAA70 displays N(ε) -acetyltransferase activity on three internal lysine residues. All MS data have been deposited in the ProteomeXchange with identifier PXD001947 (http://proteomecentral.proteomexchange.org/dataset/PXD001947).
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Affiliation(s)
- Trinh V Dinh
- Department of Plant Molecular Biology, Centre for Organismal Studies, University of HeidelbergHeidelberg, Germany
| | - Willy V Bienvenut
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-SudGif-sur-Yvette, France
| | - Eric Linster
- Department of Plant Molecular Biology, Centre for Organismal Studies, University of HeidelbergHeidelberg, Germany
- Hartmut Hoffmann-Berling International Graduate School, University of HeidelbergHeidelberg, Germany
| | - Anna Feldman-Salit
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies gGbmHHeidelberg, Germany
| | - Vincent A Jung
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-SudGif-sur-Yvette, France
| | - Thierry Meinnel
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-SudGif-sur-Yvette, France
| | - Rüdiger Hell
- Department of Plant Molecular Biology, Centre for Organismal Studies, University of HeidelbergHeidelberg, Germany
| | - Carmela Giglione
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-SudGif-sur-Yvette, France
| | - Markus Wirtz
- Department of Plant Molecular Biology, Centre for Organismal Studies, University of HeidelbergHeidelberg, Germany
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33
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Varland S, Osberg C, Arnesen T. N-terminal modifications of cellular proteins: The enzymes involved, their substrate specificities and biological effects. Proteomics 2015; 15:2385-401. [PMID: 25914051 PMCID: PMC4692089 DOI: 10.1002/pmic.201400619] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 03/04/2015] [Accepted: 04/21/2015] [Indexed: 01/18/2023]
Abstract
The vast majority of eukaryotic proteins are N-terminally modified by one or more processing enzymes. Enzymes acting on the very first amino acid of a polypeptide include different peptidases, transferases, and ligases. Methionine aminopeptidases excise the initiator methionine leaving the nascent polypeptide with a newly exposed amino acid that may be further modified. N-terminal acetyl-, methyl-, myristoyl-, and palmitoyltransferases may attach an acetyl, methyl, myristoyl, or palmitoyl group, respectively, to the α-amino group of the target protein N-terminus. With the action of ubiquitin ligases, one or several ubiquitin molecules are transferred, and hence, constitute the N-terminal modification. Modifications at protein N-termini represent an important contribution to proteomic diversity and complexity, and are essential for protein regulation and cellular signaling. Consequently, dysregulation of the N-terminal modifying enzymes is implicated in human diseases. We here review the different protein N-terminal modifications occurring co- or post-translationally with emphasis on the responsible enzymes and their substrate specificities.
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Affiliation(s)
- Sylvia Varland
- Department of Molecular Biology, University of Bergen, Bergen, Norway
| | - Camilla Osberg
- Department of Molecular Biology, University of Bergen, Bergen, Norway.,Department of Surgery, Haukeland University Hospital, Bergen, Norway
| | - Thomas Arnesen
- Department of Molecular Biology, University of Bergen, Bergen, Norway.,Department of Surgery, Haukeland University Hospital, Bergen, Norway
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34
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Structural basis of cofactor-mediated stabilization and substrate recognition of the α-tubulin acetyltransferase αTAT1. Biochem J 2015; 467:103-13. [PMID: 25602620 DOI: 10.1042/bj20141193] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The functions of microtubules are controlled in part by tubulin post-translational modification including acetylation of Lys⁴⁰ in α-tubulin. αTAT1 (α-tubulin acetyltransferase 1), an enzyme evolutionarily conserved among eukaryotes, has recently been identified as the major α-tubulin Lys⁴⁰ acetyltransferase, in which AcCoA (acetyl-CoA) serves as an acetyl group donor. The regulation and substrate recognition of this enzyme, however, have not been fully understood. In the present study, we show that AcCoA and CoA each form a stable complex with human αTAT1 to maintain the protein integrity both in vivo and in vitro. The invariant residues Arg¹³² and Ser¹⁶⁰ in αTAT1 participate in the stable interaction not only with AcCoA but also with CoA, which is supported by analysis of the present crystal structures of the αTAT1 catalytic domain in complex with CoA. Alanine substitution for Arg¹³² or Ser¹⁶⁰ leads to a drastic misfolding of the isolated αTAT1 catalytic domain in the absence of CoA and AcCoA but not in the presence of excess amounts of either cofactor. A mutant αTAT1 carrying the R132A or S160A substitution is degraded much faster than the wild-type protein when expressed in mammalian Madin-Darby canine kidney cells. Furthermore, alanine-scanning experiments using Lys⁴⁰-containing peptides reveal that α-tubulin Ser³⁸ is crucial for substrate recognition of αTAT1, whereas Asp³⁹, Ile⁴², the glycine stretch (amino acid residues 43-45) and Asp⁴⁶ are also involved. The requirement for substrate selection is totally different from that in various histone acetyltransferases, which appears to be consistent with the inability of αTAT1 to acetylate histones.
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35
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The biological functions of Naa10 - From amino-terminal acetylation to human disease. Gene 2015; 567:103-31. [PMID: 25987439 DOI: 10.1016/j.gene.2015.04.085] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 04/20/2015] [Accepted: 04/27/2015] [Indexed: 01/07/2023]
Abstract
N-terminal acetylation (NTA) is one of the most abundant protein modifications known, and the N-terminal acetyltransferase (NAT) machinery is conserved throughout all Eukarya. Over the past 50 years, the function of NTA has begun to be slowly elucidated, and this includes the modulation of protein-protein interaction, protein-stability, protein function, and protein targeting to specific cellular compartments. Many of these functions have been studied in the context of Naa10/NatA; however, we are only starting to really understand the full complexity of this picture. Roughly, about 40% of all human proteins are substrates of Naa10 and the impact of this modification has only been studied for a few of them. Besides acting as a NAT in the NatA complex, recently other functions have been linked to Naa10, including post-translational NTA, lysine acetylation, and NAT/KAT-independent functions. Also, recent publications have linked mutations in Naa10 to various diseases, emphasizing the importance of Naa10 research in humans. The recent design and synthesis of the first bisubstrate inhibitors that potently and selectively inhibit the NatA/Naa10 complex, monomeric Naa10, and hNaa50 further increases the toolset to analyze Naa10 function.
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Magin RS, Liszczak GP, Marmorstein R. The molecular basis for histone H4- and H2A-specific amino-terminal acetylation by NatD. Structure 2015; 23:332-41. [PMID: 25619998 DOI: 10.1016/j.str.2014.10.025] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 10/22/2014] [Accepted: 10/24/2014] [Indexed: 11/18/2022]
Abstract
N-terminal acetylation is among the most common protein modifications in eukaryotes and is mediated by evolutionarily conserved N-terminal acetyltransferases (NATs). NatD is among the most selective NATs; its only known substrates are histones H4 and H2A, containing the N-terminal sequence SGRGK in humans. Here we characterize the molecular basis for substrate-specific acetylation by NatD by reporting its crystal structure bound to cognate substrates and performing related biochemical studies. A novel N-terminal segment wraps around the catalytic core domain to make stabilizing interactions, and the α1-α2 and β6-β7 loops adopt novel conformations to properly orient the histone N termini in the binding site. Ser1 and Arg3 of the histone make extensive contacts to highly conserved NatD residues in the substrate binding pocket, and flanking glycine residues also appear to contribute to substrate-specific binding by NatD, together defining a Ser-Gly-Arg-Gly recognition sequence. These studies have implications for understanding substrate-specific acetylation by NAT enzymes.
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Affiliation(s)
- Robert S Magin
- Department of Biochemistry and Biophysics, Abramson Family Cancer Research Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Program in Gene Expression and Regulation, The Wistar Institute, Philadelphia, PA 19104, USA; Graduate Group in Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Glen P Liszczak
- Department of Biochemistry and Biophysics, Abramson Family Cancer Research Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ronen Marmorstein
- Department of Biochemistry and Biophysics, Abramson Family Cancer Research Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Program in Gene Expression and Regulation, The Wistar Institute, Philadelphia, PA 19104, USA; Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Van Damme P, Støve SI, Glomnes N, Gevaert K, Arnesen T. A Saccharomyces cerevisiae model reveals in vivo functional impairment of the Ogden syndrome N-terminal acetyltransferase NAA10 Ser37Pro mutant. Mol Cell Proteomics 2014; 13:2031-41. [PMID: 24408909 DOI: 10.1074/mcp.m113.035402] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
N-terminal acetylation (Nt-acetylation) occurs on the majority of eukaryotic proteins and is catalyzed by N-terminal acetyltransferases (NATs). Nt-acetylation is increasingly recognized as a vital modification with functional implications ranging from protein degradation to protein localization. Although early genetic studies in yeast demonstrated that NAT-deletion strains displayed a variety of phenotypes, only recently, the first human genetic disorder caused by a mutation in a NAT gene was reported; boys diagnosed with the X-linked Ogden syndrome harbor a p.Ser37Pro (S37P) mutation in the gene encoding Naa10, the catalytic subunit of the NatA complex, and suffer from global developmental delays and lethality during infancy. Here, we describe a Saccharomyces cerevisiae model developed by introducing the human wild-type or mutant NatA complex into yeast lacking NatA (NatA-Δ). The wild-type human NatA complex phenotypically complemented the NatA-Δ strain, whereas only a partial rescue was observed for the Ogden mutant NatA complex suggesting that hNaa10 S37P is only partially functional in vivo. Immunoprecipitation experiments revealed a reduced subunit complexation for the mutant hNatA S37P next to a reduced in vitro catalytic activity. We performed quantitative Nt-acetylome analyses on a control yeast strain (yNatA), a yeast NatA deletion strain (yNatA-Δ), a yeast NatA deletion strain expressing wild-type human NatA (hNatA), and a yeast NatA deletion strain expressing mutant human NatA (hNatA S37P). Interestingly, a generally reduced degree of Nt-acetylation was observed among a large group of NatA substrates in the yeast expressing mutant hNatA as compared with yeast expressing wild-type hNatA. Combined, these data provide strong support for the functional impairment of hNaa10 S37P in vivo and suggest that reduced Nt-acetylation of one or more target substrates contributes to the pathogenesis of the Ogden syndrome. Comparative analysis between human and yeast NatA also provided new insights into the co-evolution of the NatA complexes and their substrates. For instance, (Met-)Ala- N termini are more prevalent in the human proteome as compared with the yeast proteome, and hNatA displays a preference toward these N termini as compared with yNatA.
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Affiliation(s)
- Petra Van Damme
- From the ‡Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium; §Department of Biochemistry, Ghent University, B-9000 Ghent, Belgium;
| | - Svein I Støve
- ¶Department of Molecular Biology, University of Bergen, N-5020 Bergen, Norway; **Department of Surgery, Haukeland University Hospital, N-5021 Bergen, Norway
| | - Nina Glomnes
- ¶Department of Molecular Biology, University of Bergen, N-5020 Bergen, Norway; ‖Department of Clinical Science, University of Bergen, N-5020 Bergen, Norway; and
| | - Kris Gevaert
- From the ‡Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium; §Department of Biochemistry, Ghent University, B-9000 Ghent, Belgium
| | - Thomas Arnesen
- ¶Department of Molecular Biology, University of Bergen, N-5020 Bergen, Norway; **Department of Surgery, Haukeland University Hospital, N-5021 Bergen, Norway
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