1
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Penzo A, Palancade B. Puzzling out nuclear pore complex assembly. FEBS Lett 2023; 597:2705-2727. [PMID: 37548888 DOI: 10.1002/1873-3468.14713] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/12/2023] [Accepted: 07/17/2023] [Indexed: 08/08/2023]
Abstract
Nuclear pore complexes (NPCs) are sophisticated multiprotein assemblies embedded within the nuclear envelope and controlling the exchanges of molecules between the cytoplasm and the nucleus. In this review, we summarize the mechanisms by which these elaborate complexes are built from their subunits, the nucleoporins, based on our ever-growing knowledge of NPC structural organization and on the recent identification of additional features of this process. We present the constraints faced during the production of nucleoporins, their gathering into oligomeric complexes, and the formation of NPCs within nuclear envelopes, and review the cellular strategies at play, from co-translational assembly to the enrolment of a panel of cofactors. Remarkably, the study of NPCs can inform our perception of the biogenesis of multiprotein complexes in general - and vice versa.
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Affiliation(s)
- Arianna Penzo
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Benoit Palancade
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
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2
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Nair RR, Pataki E, Gerst JE. Transperons: RNA operons as effectors of coordinated gene expression in eukaryotes. Trends Genet 2022; 38:1217-1227. [PMID: 35934590 DOI: 10.1016/j.tig.2022.07.005] [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: 05/16/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 01/24/2023]
Abstract
Coordinated gene expression allows spatiotemporal control of cellular processes and is achieved by the cotranscription/translation of functionally related genes/proteins. Prokaryotes evolved polycistronic messages (operons) to confer expression from a single promoter to efficiently cotranslate proteins functioning on the same pathway. Yet, despite having far greater diversity (e.g., gene number, distribution, modes of expression), eukaryotic cells employ individual promoters and monocistronic messages. Although gene expression is modular, it does not account for how eukaryotes achieve coordinated localized translation. The RNA operon theory states that mRNAs derived from different chromosomes assemble into ribonucleoprotein particles (RNPs) that act as functional operons to generate protein cohorts upon cotranslation. Work in yeast has now validated this theory and shown that intergenic associations and noncanonical histone functions create pathway-specific RNA operons (transperons) that regulate cell physiology. Herein the involvement of chromatin organization in transperon formation and programmed gene coexpression is discussed.
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Affiliation(s)
- Rohini R Nair
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Emese Pataki
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Jeffrey E Gerst
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel.
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3
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Brumm S, Singh MK, Kriechbaum C, Richter S, Huhn K, Kucera T, Baumann S, Wolters H, Takada S, Jürgens G. N-terminal domain of ARF-GEF GNOM prevents heterodimerization with functionally divergent GNL1 in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 112:772-785. [PMID: 36106415 DOI: 10.1111/tpj.15979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/11/2022] [Accepted: 09/13/2022] [Indexed: 06/15/2023]
Abstract
Evolutionary change following gene duplication can lead to functionally divergent paralogous proteins. If comprising identical subunits their random assortment would also form potentially detrimental heteromeric proteins. In Arabidopsis, the ARF GTPase guanine-nucleotide exchange factor GNOM is essential for polar recycling of auxin-efflux transporter PIN1 from endosomes to the basal plasma membrane whereas its paralog GNL1 mediates retrograde Golgi-endoplasmic reticulum traffic. Here we show that both GNOM and GNL1 form homodimers but no heterodimers. To assess the biological significance of this, we generated transgenic plants expressing engineered heterodimer-compatible GNOM variants. Those plants showed developmental defects such as the failure to produce lateral roots. To identify mechanisms underlying heterodimer prevention, we analyzed interactions of the N-terminal dimerization and cyclophilin-binding (DCB) domain. Each DCB domain interacted with the complementary fragment (ΔDCB) both of their own and of the paralogous protein. However, only DCBGNOM interacted with itself whereas DCBGNL1 failed to interact with itself and with DCBGNOM . GNOM variants in which the DCB domain was removed or replaced by DCBGNL1 revealed a role for DCB-DCB interaction in the prevention of GNOM-GNL1 heterodimers whereas DCB-ΔDCB interaction was essential for dimer formation and GNOM function. Our data suggest a model of early DCB-DCB interaction that facilitates GNOM homodimer formation, indirectly precluding formation of detrimental heterodimers.
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Affiliation(s)
- Sabine Brumm
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Manoj K Singh
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Choy Kriechbaum
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Sandra Richter
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Kerstin Huhn
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Tim Kucera
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Sarah Baumann
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Hanno Wolters
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Shinobu Takada
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Gerd Jürgens
- Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
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4
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Badonyi M, Marsh JA. Large protein complex interfaces have evolved to promote cotranslational assembly. eLife 2022; 11:79602. [PMID: 35899946 PMCID: PMC9365393 DOI: 10.7554/elife.79602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Assembly pathways of protein complexes should be precise and efficient to minimise misfolding and unwanted interactions with other proteins in the cell. One way to achieve this efficiency is by seeding assembly pathways during translation via the cotranslational assembly of subunits. While recent evidence suggests that such cotranslational assembly is widespread, little is known about the properties of protein complexes associated with the phenomenon. Here, using a combination of proteome-specific protein complex structures and publicly available ribosome profiling data, we show that cotranslational assembly is particularly common between subunits that form large intermolecular interfaces. To test whether large interfaces have evolved to promote cotranslational assembly, as opposed to cotranslational assembly being a non-adaptive consequence of large interfaces, we compared the sizes of first and last translated interfaces of heteromeric subunits in bacterial, yeast, and human complexes. When considering all together, we observe the N-terminal interface to be larger than the C-terminal interface 54% of the time, increasing to 64% when we exclude subunits with only small interfaces, which are unlikely to cotranslationally assemble. This strongly suggests that large interfaces have evolved as a means to maximise the chance of successful cotranslational subunit binding.
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Affiliation(s)
- Mihaly Badonyi
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, United Kingdom
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, United Kingdom
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5
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Alvarez-Sieiro P, Sikkema HR, Poolman B. Heterodimer Formation of the Homodimeric ABC Transporter OpuA. Int J Mol Sci 2021; 22:ijms22115912. [PMID: 34072847 PMCID: PMC8199443 DOI: 10.3390/ijms22115912] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/28/2021] [Accepted: 05/28/2021] [Indexed: 11/16/2022] Open
Abstract
Many proteins have a multimeric structure and are composed of two or more identical subunits. While this can be advantageous for the host organism, it can be a challenge when targeting specific residues in biochemical analyses. In vitro splitting and re-dimerization to circumvent this problem is a tedious process that requires stable proteins. We present an in vivo approach to transform homodimeric proteins into apparent heterodimers, which then can be purified using two-step affinity-tag purification. This opens the door to both practical applications such as smFRET to probe the conformational dynamics of homooligomeric proteins and fundamental research into the mechanism of protein multimerization, which is largely unexplored for membrane proteins. We show that expression conditions are key for the formation of heterodimers and that the order of the differential purification and reconstitution of the protein into nanodiscs is important for a functional ABC-transporter complex.
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6
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Morales-Polanco F, Bates C, Lui J, Casson J, Solari CA, Pizzinga M, Forte G, Griffin C, Garner KEL, Burt HE, Dixon HL, Hubbard S, Portela P, Ashe MP. Core Fermentation (CoFe) granules focus coordinated glycolytic mRNA localization and translation to fuel glucose fermentation. iScience 2021; 24:102069. [PMID: 33554071 PMCID: PMC7859310 DOI: 10.1016/j.isci.2021.102069] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/16/2020] [Accepted: 01/12/2021] [Indexed: 12/24/2022] Open
Abstract
Glycolysis is a fundamental metabolic pathway for glucose catabolism across biology, and glycolytic enzymes are among the most abundant proteins in cells. Their expression at such levels provides a particular challenge. Here we demonstrate that the glycolytic mRNAs are localized to granules in yeast and human cells. Detailed live cell and smFISH studies in yeast show that the mRNAs are actively translated in granules, and this translation appears critical for the localization. Furthermore, this arrangement is likely to facilitate the higher level organization and control of the glycolytic pathway. Indeed, the degree of fermentation required by cells is intrinsically connected to the extent of mRNA localization to granules. On this basis, we term these granules, core fermentation (CoFe) granules; they appear to represent translation factories, allowing high-level coordinated enzyme synthesis for a critical metabolic pathway.
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Affiliation(s)
- Fabian Morales-Polanco
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Christian Bates
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Jennifer Lui
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Joseph Casson
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Clara A Solari
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IQUIBICEN-CONICET, Buenos Aires, Argentina
| | - Mariavittoria Pizzinga
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Gabriela Forte
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Claire Griffin
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Kirsten E L Garner
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Harriet E Burt
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Hannah L Dixon
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Simon Hubbard
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Paula Portela
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IQUIBICEN-CONICET, Buenos Aires, Argentina
| | - Mark P Ashe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
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7
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Collart MA, Weiss B. Ribosome pausing, a dangerous necessity for co-translational events. Nucleic Acids Res 2020; 48:1043-1055. [PMID: 31598688 PMCID: PMC7026645 DOI: 10.1093/nar/gkz763] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 08/13/2019] [Accepted: 08/21/2019] [Indexed: 12/31/2022] Open
Abstract
In recent years translation elongation has emerged as an important contributor to the regulation of gene expression. There are multiple quality control checkpoints along the way of producing mature proteins and targeting them to the right cellular compartment, or associating them correctly with their partners. Ribosomes pause to allow co-translational protein folding, protein targeting or protein interactions, and the pausing is dictated by a combination of the mRNA sequence and structure, the tRNA availability and the nascent peptide. However, ribosome pausing can also lead to ribosome collisions and co-translational degradation of both mRNA and nascent chain. Understanding how the translating ribosome tunes the different maturation steps that nascent proteins must undergo, what the timing of these maturation events is, and how degradation can be avoided when pausing is needed, is now possible by the emergence of methods to follow ribosome dynamics in vivo. This review summarizes some of the recent studies that have advanced our knowledge about co-translational events using the power of ribosome profiling, and some of the questions that have emerged from these studies.
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Affiliation(s)
- Martine A Collart
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Institute of Genetics and Genomics, Geneva, 1 rue Michel Servet, 1211 Genève 4, Switzerland
| | - Benjamin Weiss
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Institute of Genetics and Genomics, Geneva, 1 rue Michel Servet, 1211 Genève 4, Switzerland
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8
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Omomyc Reveals New Mechanisms To Inhibit the MYC Oncogene. Mol Cell Biol 2019; 39:MCB.00248-19. [PMID: 31501275 PMCID: PMC6817756 DOI: 10.1128/mcb.00248-19] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 08/07/2019] [Indexed: 11/21/2022] Open
Abstract
The MYC oncogene is upregulated in human cancers by translocation, amplification, and mutation of cellular pathways that regulate Myc. Myc/Max heterodimers bind to E box sequences in the promoter regions of genes and activate transcription. The MYC oncogene is upregulated in human cancers by translocation, amplification, and mutation of cellular pathways that regulate Myc. Myc/Max heterodimers bind to E box sequences in the promoter regions of genes and activate transcription. The MYC inhibitor Omomyc can reduce the ability of MYC to bind specific box sequences in promoters of MYC target genes by binding directly to E box sequences as demonstrated by chromatin immunoprecipitation (CHIP). Here, we demonstrate by both a proximity ligation assay (PLA) and double chromatin immunoprecipitation (ReCHIP) that Omomyc preferentially binds to Max, not Myc, to mediate inhibition of MYC-mediated transcription by replacing MYC/MAX heterodimers with Omomyc/MAX heterodimers. The formation of Myc/Max and Omomyc/Max heterodimers occurs cotranslationally; Myc, Max, and Omomyc can interact with ribosomes and Max RNA under conditions in which ribosomes are intact. Taken together, our data suggest that the mechanism of action of Omomyc is to bind DNA as either a homodimer or a heterodimer with Max that is formed cotranslationally, revealing a novel mechanism to inhibit the MYC oncogene. We find that in vivo, Omomyc distributes quickly to kidneys and liver and has a short effective half-life in plasma, which could limit its use in vivo.
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9
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The Benefits of Cotranslational Assembly: A Structural Perspective. Trends Cell Biol 2019; 29:791-803. [DOI: 10.1016/j.tcb.2019.07.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 07/13/2019] [Accepted: 07/15/2019] [Indexed: 12/20/2022]
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10
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Pickel C, Günter J, Ruiz-Serrano A, Spielmann P, Fabrizio JA, Wolski W, Peet DJ, Wenger RH, Scholz CC. Oxygen-dependent bond formation with FIH regulates the activity of the client protein OTUB1. Redox Biol 2019; 26:101265. [PMID: 31299612 PMCID: PMC6624438 DOI: 10.1016/j.redox.2019.101265] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/28/2019] [Accepted: 06/30/2019] [Indexed: 12/30/2022] Open
Abstract
Protein:protein interactions are the basis of molecular communication and are usually of transient non-covalent nature, while covalent interactions other than ubiquitination are rare. For cellular adaptations, the cellular oxygen and peroxide sensor factor inhibiting HIF (FIH) confers oxygen and oxidant stress sensitivity to the hypoxia inducible factor (HIF) by asparagine hydroxylation. We investigated whether FIH contributes to hypoxia adaptation also through other mechanisms and identified a hypoxia sensitive, likely covalent, bond formation by FIH with several client proteins, including the deubiquitinase ovarian tumor domain containing ubiquitin aldehyde binding protein 1 (OTUB1). Biochemical analyses were consistent with a co-translational amide bond formation between FIH and OTUB1, occurring within mammalian and bacterial cells but not between separately purified proteins. Bond formation is catalysed by FIH and highly dependent on oxygen availability in the cellular microenvironment. Within cells, a heterotrimeric complex is formed, consisting of two FIH and one covalently linked OTUB1. Complexation of OTUB1 by FIH regulates OTUB1 deubiquitinase activity. Our findings reveal an alternative mechanism for hypoxia adaptation with remarkably high oxygen sensitivity, mediated through covalent protein-protein interactions catalysed by an asparagine modifying dioxygenase. FIH forms a (likely amide) bond with client proteins. Bond formation is highly hypoxia sensitive and occurs co-translationally. FIH forms a heterotrimer with the client protein OTUB1 (FIH2OTUB11). Complex formation between OTUB1 and FIH regulates OTUB1 deubiquitinase activity. Bond formation by hydroxylases is an alternative mechanism for hypoxia adaptation.
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Affiliation(s)
- Christina Pickel
- Institute of Physiology, University of Zurich, 8057, Zurich, Switzerland
| | - Julia Günter
- Institute of Physiology, University of Zurich, 8057, Zurich, Switzerland; National Centre of Competence in Research 'Kidney.CH', Switzerland
| | | | - Patrick Spielmann
- Institute of Physiology, University of Zurich, 8057, Zurich, Switzerland
| | | | - Witold Wolski
- Functional Genomics Center Zurich, University of Zurich, 8057, Zurich, Switzerland
| | - Daniel J Peet
- School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Roland H Wenger
- Institute of Physiology, University of Zurich, 8057, Zurich, Switzerland; National Centre of Competence in Research 'Kidney.CH', Switzerland.
| | - Carsten C Scholz
- Institute of Physiology, University of Zurich, 8057, Zurich, Switzerland; National Centre of Competence in Research 'Kidney.CH', Switzerland.
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11
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Diepold A. Assembly and Post-assembly Turnover and Dynamics in the Type III Secretion System. Curr Top Microbiol Immunol 2019; 427:35-66. [PMID: 31218503 DOI: 10.1007/82_2019_164] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The type III secretion system (T3SS) is one of the largest transmembrane complexes in bacteria, comprising several intricately linked and embedded substructures. The assembly of this nanomachine is a hierarchical process which is regulated and controlled by internal and external cues at several critical points. Recently, it has become obvious that the assembly of the T3SS is not a unidirectional and deterministic process, but that parts of the T3SS constantly exchange or rearrange. This article aims to give an overview on the assembly and post-assembly dynamics of the T3SS, with a focus on emerging general concepts and adaptations of the general assembly pathway.
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Affiliation(s)
- Andreas Diepold
- Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Straße 10, 35043, Marburg, Germany.
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12
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Tusk SE, Delalez NJ, Berry RM. Subunit Exchange in Protein Complexes. J Mol Biol 2018; 430:4557-4579. [DOI: 10.1016/j.jmb.2018.06.039] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 06/21/2018] [Accepted: 06/21/2018] [Indexed: 01/09/2023]
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13
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Wojcikiewicz RJH. The Making and Breaking of Inositol 1,4,5-Trisphosphate Receptor Tetramers. ACTA ACUST UNITED AC 2018; 6:45-49. [PMID: 30581688 DOI: 10.1166/msr.2018.1073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Mammalian cells express three highly conserved inositol 1,4,5-trisphosphate (IP3) receptor types (IP3R1, IP3R2 and IP3R3), which have broadly similar characteristics, but markedly different distributions, and form homo- or heterotetrameric Ca2+ channels in endoplasmic reticulum (ER) membranes. A vast array of published work details how mature, ER membrane-located IP3 receptor tetramers are regulated, but much less attention has been paid to the intriguing questions of how the tetramers are assembled and destroyed as part of their natural life cycle. Are they assembled at the ER membrane from nascent, or completely translated polypeptides? How are they disassembled and degraded? These questions and other recently defined modes of IP3 receptor processing will be briefly reviewed.
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14
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Natan E, Endoh T, Haim-Vilmovsky L, Flock T, Chalancon G, Hopper JTS, Kintses B, Horvath P, Daruka L, Fekete G, Pál C, Papp B, Oszi E, Magyar Z, Marsh JA, Elcock AH, Babu MM, Robinson CV, Sugimoto N, Teichmann SA. Cotranslational protein assembly imposes evolutionary constraints on homomeric proteins. Nat Struct Mol Biol 2018; 25:279-288. [PMID: 29434345 PMCID: PMC5995306 DOI: 10.1038/s41594-018-0029-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 01/10/2018] [Indexed: 01/11/2023]
Abstract
Cotranslational protein folding can facilitate rapid formation of functional structures. However, it can also cause premature assembly of protein complexes, if two interacting nascent chains are in close proximity. By analyzing known protein structures, we show that homomeric protein contacts are enriched toward the C termini of polypeptide chains across diverse proteomes. We hypothesize that this is the result of evolutionary constraints for folding to occur before assembly. Using high-throughput imaging of protein homomers in Escherichia coli and engineered protein constructs with N- and C-terminal oligomerization domains, we show that, indeed, proteins with C-terminal homomeric interface residues consistently assemble more efficiently than those with N-terminal interface residues. Using in vivo, in vitro and in silico experiments, we identify features that govern successful assembly of homomers, which have implications for protein design and expression optimization.
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Affiliation(s)
| | - Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, Kobe, Japan
| | - Liora Haim-Vilmovsky
- EMBL-European Bioinformatics Institute, Wellcome Trust Genome Campus, Cambridge, UK
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Tilman Flock
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | | | | | - Bálint Kintses
- Synthetic and System Biology Unit, Biological Research Center of the Hungarian Academia of Sciences, Szeged, Hungary
| | - Peter Horvath
- Synthetic and System Biology Unit, Biological Research Center of the Hungarian Academia of Sciences, Szeged, Hungary
- Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
| | - Lejla Daruka
- Synthetic and System Biology Unit, Biological Research Center of the Hungarian Academia of Sciences, Szeged, Hungary
| | - Gergely Fekete
- Synthetic and System Biology Unit, Biological Research Center of the Hungarian Academia of Sciences, Szeged, Hungary
| | - Csaba Pál
- Synthetic and System Biology Unit, Biological Research Center of the Hungarian Academia of Sciences, Szeged, Hungary
| | - Balázs Papp
- Synthetic and System Biology Unit, Biological Research Center of the Hungarian Academia of Sciences, Szeged, Hungary
| | - Erika Oszi
- Institute of Plant Biology, Biological Research Center of the Hungarian Academia of Sciences, Szeged, Hungary
| | - Zoltán Magyar
- Institute of Plant Biology, Biological Research Center of the Hungarian Academia of Sciences, Szeged, Hungary
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Adrian H Elcock
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
| | - M Madan Babu
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | | | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, Kobe, Japan
- Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, Kobe, Japan
| | - Sarah A Teichmann
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Cambridge, UK.
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
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15
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Komar AA. Unraveling co-translational protein folding: Concepts and methods. Methods 2017; 137:71-81. [PMID: 29221924 DOI: 10.1016/j.ymeth.2017.11.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/13/2017] [Indexed: 12/26/2022] Open
Abstract
Advances in techniques such as nuclear magnetic resonance spectroscopy, cryo-electron microscopy, and single-molecule and time-resolved fluorescent approaches are transforming our ability to study co-translational protein folding both in vivo in living cells and in vitro in reconstituted cell-free translation systems. These approaches provide comprehensive information on the spatial organization and dynamics of nascent polypeptide chains and the kinetics of co-translational protein folding. This information has led to an improved understanding of the process of protein folding in living cells and should allow remaining key questions in the field, such as what structures are formed within nascent chains during protein synthesis and when, to be answered. Ultimately, studies using these techniques will facilitate development of a unified concept of protein folding, a process that is essential for proper cell function and organism viability. This review describes current methods for analysis of co-translational protein folding with an emphasis on some of the recently developed techniques that allow monitoring of co-translational protein folding in real-time.
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Affiliation(s)
- Anton A Komar
- Center for Gene Regulation in Health and Disease and Department of Biological, Geological and Environmental Sciences, Cleveland State University, Cleveland, OH 44115, USA; Department of Biochemistry and the Center for RNA Science and Therapeutics, Case Western Reserve University, Cleveland, OH 44106, USA; Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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16
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Auboeuf D. Genome evolution is driven by gene expression-generated biophysical constraints through RNA-directed genetic variation: A hypothesis. Bioessays 2017; 39. [DOI: 10.1002/bies.201700069] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Didier Auboeuf
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210; Laboratory of Biology and Modelling of the Cell; Site Jacques Monod; Lyon France
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17
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Abstract
3'-untranslated regions (3'-UTRs) are the noncoding parts of mRNAs. Compared to yeast, in humans, median 3'-UTR length has expanded approximately tenfold alongside an increased generation of alternative 3'-UTR isoforms. In contrast, the number of coding genes, as well as coding region length, has remained similar. This suggests an important role for 3'-UTRs in the biology of higher organisms. 3'-UTRs are best known to regulate diverse fates of mRNAs, including degradation, translation, and localization, but they can also function like long noncoding or small RNAs, as has been shown for whole 3'-UTRs as well as for cleaved fragments. Furthermore, 3'-UTRs determine the fate of proteins through the regulation of protein-protein interactions. They facilitate cotranslational protein complex formation, which establishes a role for 3'-UTRs as evolved eukaryotic operons. Whereas bacterial operons promote the interaction of two subunits, 3'-UTRs enable the formation of protein complexes with diverse compositions. All of these 3'-UTR functions are accomplished by effector proteins that are recruited by RNA-binding proteins that bind to 3'-UTR cis-elements. In summary, 3'-UTRs seem to be major players in gene regulation that enable local functions, compartmentalization, and cooperativity, which makes them important tools for the regulation of phenotypic diversity of higher organisms.
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Affiliation(s)
- Christine Mayr
- Department of Cancer Biology and Genetics, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA;
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18
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Signalling assemblies: the odds of symmetry. Biochem Soc Trans 2017; 45:599-611. [PMID: 28620024 DOI: 10.1042/bst20170009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 02/27/2017] [Accepted: 02/28/2017] [Indexed: 02/06/2023]
Abstract
The assembly of proteins into complexes is fundamental to nearly all biological signalling processes. Symmetry is a dominant feature of the structures of experimentally determined protein complexes, observed in the vast majority of homomers and many heteromers. However, some asymmetric structures exist, and asymmetry also often forms transiently, intractable to traditional structure determination methods. Here, we explore the role of protein complex symmetry and asymmetry in cellular signalling, focusing on receptors, transcription factors and transmembrane channels, among other signalling assemblies. We highlight a recurrent tendency for asymmetry to be crucial for signalling function, often being associated with activated states. We conclude with a discussion of how consideration of protein complex symmetry and asymmetry has significant potential implications and applications for pharmacology and human disease.
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19
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Bergendahl LT, Marsh JA. Functional determinants of protein assembly into homomeric complexes. Sci Rep 2017; 7:4932. [PMID: 28694495 PMCID: PMC5504011 DOI: 10.1038/s41598-017-05084-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 05/24/2017] [Indexed: 11/24/2022] Open
Abstract
Approximately half of proteins with experimentally determined structures can interact with other copies of themselves and assemble into homomeric complexes, the overwhelming majority of which (>96%) are symmetric. Although homomerisation is often assumed to a functionally beneficial result of evolutionary selection, there has been little systematic analysis of the relationship between homomer structure and function. Here, utilizing the large numbers of structures and functional annotations now available, we have investigated how proteins that assemble into different types of homomers are associated with different biological functions. We observe that homomers from different symmetry groups are significantly enriched in distinct functions, and can often provide simple physical and geometrical explanations for these associations in regards to substrate recognition or physical environment. One of the strongest associations is the tendency for metabolic enzymes to form dihedral complexes, which we suggest is closely related to allosteric regulation. We provide a physical explanation for why allostery is related to dihedral complexes: it allows for efficient propagation of conformational changes across isologous (i.e. symmetric) interfaces. Overall we demonstrate a clear relationship between protein function and homomer symmetry that has important implications for understanding protein evolution, as well as for predicting protein function and quaternary structure.
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Affiliation(s)
- L Therese Bergendahl
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, EH4 2XU, UK.
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, EH4 2XU, UK
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20
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Regulation, evolution and consequences of cotranslational protein complex assembly. Curr Opin Struct Biol 2016; 42:90-97. [PMID: 27969102 DOI: 10.1016/j.sbi.2016.11.023] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 11/28/2016] [Indexed: 01/05/2023]
Abstract
Most proteins assemble into complexes, which are involved in almost all cellular processes. Thus it is crucial for cell viability that mechanisms for correct assembly exist. The timing of assembly plays a key role in determining the fate of the protein: if the protein is allowed to diffuse into the crowded cellular milieu, it runs the risk of forming non-specific interactions, potentially leading to aggregation or other deleterious outcomes. It is therefore expected that strong regulatory mechanisms should exist to ensure efficient assembly. In this review we discuss the cotranslational assembly of protein complexes and discuss how it occurs, ways in which it is regulated, potential disadvantages of cotranslational interactions between proteins and the implications for the inheritance of dominant-negative genetic disorders.
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Abstract
Understanding the molecular mechanisms behind the capacity of cancer cells to adapt to the tumor microenvironment and to anticancer therapies is a major challenge. In this context, cancer is believed to be an evolutionary process where random mutations and the selection process shape the mutational pattern and phenotype of cancer cells. This article challenges the notion of randomness of some cancer-associated mutations by describing molecular mechanisms involving stress-mediated biogenesis of mRNA-derived small RNAs able to target and increase the local mutation rate of the genomic loci they originate from. It is proposed that the probability of some mutations at specific loci could be increased in a stress-specific and RNA-depending manner. This would increase the probability of generating mutations that could alleviate stress situations, such as those triggered by anticancer drugs. Such a mechanism is made possible because tumor- and anticancer drug-associated stress situations trigger both cellular reprogramming and inflammation, which leads cancer cells to express molecular tools allowing them to “attack” and mutate their own genome in an RNA-directed manner.
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Affiliation(s)
- Didier Auboeuf
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, Lyon, France
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22
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McEntagart M, Williamson KA, Rainger JK, Wheeler A, Seawright A, De Baere E, Verdin H, Bergendahl LT, Quigley A, Rainger J, Dixit A, Sarkar A, López Laso E, Sanchez-Carpintero R, Barrio J, Bitoun P, Prescott T, Riise R, McKee S, Cook J, McKie L, Ceulemans B, Meire F, Temple IK, Prieur F, Williams J, Clouston P, Németh AH, Banka S, Bengani H, Handley M, Freyer E, Ross A, van Heyningen V, Marsh JA, Elmslie F, FitzPatrick DR. A Restricted Repertoire of De Novo Mutations in ITPR1 Cause Gillespie Syndrome with Evidence for Dominant-Negative Effect. Am J Hum Genet 2016; 98:981-992. [PMID: 27108798 PMCID: PMC4863663 DOI: 10.1016/j.ajhg.2016.03.018] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 03/16/2016] [Indexed: 12/19/2022] Open
Abstract
Gillespie syndrome (GS) is characterized by bilateral iris hypoplasia, congenital hypotonia, non-progressive ataxia, and progressive cerebellar atrophy. Trio-based exome sequencing identified de novo mutations in ITPR1 in three unrelated individuals with GS recruited to the Deciphering Developmental Disorders study. Whole-exome or targeted sequence analysis identified plausible disease-causing ITPR1 mutations in 10/10 additional GS-affected individuals. These ultra-rare protein-altering variants affected only three residues in ITPR1: Glu2094 missense (one de novo, one co-segregating), Gly2539 missense (five de novo, one inheritance uncertain), and Lys2596 in-frame deletion (four de novo). No clinical or radiological differences were evident between individuals with different mutations. ITPR1 encodes an inositol 1,4,5-triphosphate-responsive calcium channel. The homo-tetrameric structure has been solved by cryoelectron microscopy. Using estimations of the degree of structural change induced by known recessive- and dominant-negative mutations in other disease-associated multimeric channels, we developed a generalizable computational approach to indicate the likely mutational mechanism. This analysis supports a dominant-negative mechanism for GS variants in ITPR1. In GS-derived lymphoblastoid cell lines (LCLs), the proportion of ITPR1-positive cells using immunofluorescence was significantly higher in mutant than control LCLs, consistent with an abnormality of nuclear calcium signaling feedback control. Super-resolution imaging supports the existence of an ITPR1-lined nucleoplasmic reticulum. Mice with Itpr1 heterozygous null mutations showed no major iris defects. Purkinje cells of the cerebellum appear to be the most sensitive to impaired ITPR1 function in humans. Iris hypoplasia is likely to result from either complete loss of ITPR1 activity or structure-specific disruption of multimeric interactions.
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Affiliation(s)
- Meriel McEntagart
- Medical Genetics, St George's University Hospitals NHS Foundation Trust, Cranmer Terrace, London SW17 0RE, UK
| | - Kathleen A Williamson
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Jacqueline K Rainger
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Ann Wheeler
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Anne Seawright
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Elfride De Baere
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Medical Research Building (MRB), 1st Floor, Room 110.029, De Pintelaan 185, 9000 Ghent, Belgium
| | - Hannah Verdin
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Medical Research Building (MRB), 1st Floor, Room 110.029, De Pintelaan 185, 9000 Ghent, Belgium
| | - L Therese Bergendahl
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Alan Quigley
- Department of Radiology, Royal Hospital for Sick Children, Edinburgh EH9 1LF, UK
| | - Joe Rainger
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK; Roslin Institute, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Abhijit Dixit
- Clinical Genetics, Nottingham City Hospital, Hucknall Road, Nottingham NG5 1PB, UK
| | - Ajoy Sarkar
- Clinical Genetics, Nottingham City Hospital, Hucknall Road, Nottingham NG5 1PB, UK
| | - Eduardo López Laso
- Pediatric Neurology Unit, Department of Pediatrics, Reina Sofia University Hospital, Av. Menéndez Pidal s/n, 14004 Córdoba, Spain
| | - Rocio Sanchez-Carpintero
- Paediatric Neurology Unit, Department of Paediatrics, Clinica Universidad de Navarra, 31008 Pamplona, Spain
| | - Jesus Barrio
- Department of Ophthalmology, Clinica Universidad de Navarra, 31008 Pamplona, Spain
| | - Pierre Bitoun
- Service de pédiatrie, CHU Paris Seine-Saint-Denis - Hôpital Jean Verdier Avenue du 14 juillet, 93140 Bondy, France
| | - Trine Prescott
- Department of Medical Genetics, Oslo University Hospital, 0424 Oslo, Norway
| | - Ruth Riise
- Department of Ophthalmology, Innland Hospital, 2418 Elverum, Norway
| | - Shane McKee
- Northern Ireland Regional Genetics Service, Belfast City Hospital, Belfast BT9 7AB, UK
| | - Jackie Cook
- Sheffield Clinical Genetics Service, Sheffield Children's Hospital, Western Bank, Sheffield S10 2TH, UK
| | - Lisa McKie
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Berten Ceulemans
- Department of Neurology-Pediatric Neurology, University and University Hospital Antwerp, Antwerp 2650, Belgium
| | - Françoise Meire
- Department of Ophthalmology, Queen Fabiola Children's University Hospital, 1020 Brussels, Belgium
| | - I Karen Temple
- Human Development and Health Academic Unit, University Hospital Southampton, Tremona Road, University of Southampton, Southampton SO16 6YD, UK
| | - Fabienne Prieur
- Service Génétique, Plateau de biologie, CHU Saint Etienne, 42055 Saint Etienne cedex 2, France
| | - Jonathan Williams
- Oxford University Hospitals NHS Trust, Oxford Medical Genetics Laboratories, The Churchill Hospital, Old Road, Headington, Oxford OX3 7LE, UK
| | - Penny Clouston
- Oxford University Hospitals NHS Trust, Oxford Medical Genetics Laboratories, The Churchill Hospital, Old Road, Headington, Oxford OX3 7LE, UK
| | - Andrea H Németh
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford OX3 7LJ, UK
| | - Siddharth Banka
- Manchester Centre for Genomic Medicine, University of Manchester, St. Mary's Hospital, Oxford Road, Manchester M13 9WL, UK
| | - Hemant Bengani
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Mark Handley
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Elisabeth Freyer
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Allyson Ross
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Veronica van Heyningen
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Joseph A Marsh
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Frances Elmslie
- Medical Genetics, St George's University Hospitals NHS Foundation Trust, Cranmer Terrace, London SW17 0RE, UK
| | - David R FitzPatrick
- MRC Human Genetics Unit, IGMM, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK.
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23
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Ellgaard L, McCaul N, Chatsisvili A, Braakman I. Co- and Post-Translational Protein Folding in the ER. Traffic 2016; 17:615-38. [PMID: 26947578 DOI: 10.1111/tra.12392] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 02/26/2016] [Accepted: 03/03/2016] [Indexed: 12/19/2022]
Abstract
The biophysical rules that govern folding of small, single-domain proteins in dilute solutions are now quite well understood. The mechanisms underlying co-translational folding of multidomain and membrane-spanning proteins in complex cellular environments are often less clear. The endoplasmic reticulum (ER) produces a plethora of membrane and secretory proteins, which must fold and assemble correctly before ER exit - if these processes fail, misfolded species accumulate in the ER or are degraded. The ER differs from other cellular organelles in terms of the physicochemical environment and the variety of ER-specific protein modifications. Here, we review chaperone-assisted co- and post-translational folding and assembly in the ER and underline the influence of protein modifications on these processes. We emphasize how method development has helped advance the field by allowing researchers to monitor the progression of folding as it occurs inside living cells, while at the same time probing the intricate relationship between protein modifications during folding.
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Affiliation(s)
- Lars Ellgaard
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Nicholas McCaul
- Cellular Protein Chemistry, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Anna Chatsisvili
- Cellular Protein Chemistry, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Ineke Braakman
- Cellular Protein Chemistry, Faculty of Science, Utrecht University, Utrecht, The Netherlands
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24
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Wells JN, Bergendahl LT, Marsh JA. Operon Gene Order Is Optimized for Ordered Protein Complex Assembly. Cell Rep 2016; 14:679-685. [PMID: 26804901 PMCID: PMC4742563 DOI: 10.1016/j.celrep.2015.12.085] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 11/07/2015] [Accepted: 12/17/2015] [Indexed: 01/07/2023] Open
Abstract
The assembly of heteromeric protein complexes is an inherently stochastic process in which multiple genes are expressed separately into proteins, which must then somehow find each other within the cell. Here, we considered one of the ways by which prokaryotic organisms have attempted to maximize the efficiency of protein complex assembly: the organization of subunit-encoding genes into operons. Using structure-based assembly predictions, we show that operon gene order has been optimized to match the order in which protein subunits assemble. Exceptions to this are almost entirely highly expressed proteins for which assembly is less stochastic and for which precisely ordered translation offers less benefit. Overall, these results show that ordered protein complex assembly pathways are of significant biological importance and represent a major evolutionary constraint on operon gene organization. Operon-encoded subunits tend to be encoded by neighboring genes and form large interfaces Operon gene order is often optimized for the order of protein complex assembly Exceptions are mostly highly expressed proteins for which assembly is less stochastic
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Affiliation(s)
- Jonathan N Wells
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom
| | - L Therese Bergendahl
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom.
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