1
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Chapman JH, Youle AM, Grimme AL, Neuman K, Hogg J. UPF1 ATPase autoinhibition and activation modulate RNA binding kinetics and NMD efficiency. Nucleic Acids Res 2024; 52:5376-5391. [PMID: 38412299 PMCID: PMC11109973 DOI: 10.1093/nar/gkae136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/31/2024] [Accepted: 02/13/2024] [Indexed: 02/29/2024] Open
Abstract
The RNA helicase UPF1 interacts with mRNAs, mRNA decay machinery, and the terminating ribosome to promote nonsense-mediated mRNA decay (NMD). Structural and biochemical data have revealed that UPF1 exists in an enzymatically autoinhibited 'closed' state. Upon binding the NMD protein UPF2, UPF1 undergoes an extensive conformational change into a more enzymatically active 'open' state, which exhibits enhanced ATPase and helicase activity. However, mechanically deficient UPF1 mutants (i.e. poorly processive, slow, and mechanochemically uncoupled) can support efficient NMD, bringing into question the roles of UPF1 enzymatic autoinhibition and activation in NMD. Here, we identify two additional important features of the activated open state: slower RNA binding kinetics and enhanced ATP-stimulated RNA dissociation kinetics. Computational modeling based on empirical measurements of UPF1, UPF2 and RNA interaction kinetics predicts that the majority of UPF1-RNA binding and dissociation events in cells occur independently of UPF2 binding. We find that UPF1 mutants with either reduced or accelerated dissociation from RNA have NMD defects, whereas UPF1 mutants that are more dependent on UPF2 for catalytic activity remain active on well-established NMD targets. These findings support a model in which the kinetics of UPF1-mRNA interactions are important determinants of cellular NMD efficiency.
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Affiliation(s)
- Joseph H Chapman
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Alice M Youle
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Acadia L Grimme
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Keir C Neuman
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - J Robert Hogg
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
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2
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Janvier A, Hayek H, Alghoul F, Gross L, Allmang C, Martin F, Eriani G. Purification of In Vivo or In Vitro-Assembled RNA-Protein Complexes by RNA Centric Methods. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 3234:17-29. [PMID: 38507197 DOI: 10.1007/978-3-031-52193-5_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
Throughout their entire life cycle, RNAs are associated with RNA-binding proteins (RBPs), forming ribonucleoprotein (RNP) complexes with highly dynamic compositions and very diverse functions in RNA metabolism, including splicing, translational regulation, ribosome assembly. Many RNPs remain poorly characterized due to the challenges inherent in their purification and subsequent biochemical characterization. Therefore, developing methods to isolate specific RNA-protein complexes is an important initial step toward understanding their function. Many elegant methodologies have been developed to isolate RNPs. This chapter describes different approaches and methods devised for RNA-specific purification of a target RNP. We focused on general methods for selecting RNPs that target a given RNA under conditions favourable for the copurification of associated factors including RNAs and protein components of the RNP.
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Affiliation(s)
- Aurélie Janvier
- Architecture et Réactivité de l'ARN, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France
| | - Hassan Hayek
- Architecture et Réactivité de l'ARN, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France
| | - Fatima Alghoul
- Architecture et Réactivité de l'ARN, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France
| | - Lauriane Gross
- Architecture et Réactivité de l'ARN, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France
| | - Christine Allmang
- Architecture et Réactivité de l'ARN, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France
| | - Franck Martin
- Architecture et Réactivité de l'ARN, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France
| | - Gilbert Eriani
- Architecture et Réactivité de l'ARN, Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg, France.
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3
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Chapman JH, Youle AM, Grimme AL, Neuman KC, Hogg JR. UPF1 ATPase autoinhibition and activation modulate RNA binding kinetics and NMD efficiency. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.03.565554. [PMID: 38076847 PMCID: PMC10705565 DOI: 10.1101/2023.11.03.565554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
The RNA helicase UPF1 interacts with mRNAs, mRNA decay machinery, and the terminating ribosome to promote nonsense-mediated mRNA decay (NMD). Structural and biochemical data have revealed that UPF1 exists in an enzymatically autoinhibited "closed" state. Upon binding the NMD protein UPF2, UPF1 undergoes an extensive conformational change into a more enzymatically active "open" state, which exhibits enhanced ATPase and helicase activity. However, mechanically deficient UPF1 mutants can support efficient NMD, bringing into question the roles of UPF1 enzymatic autoinhibition and activation in NMD. Here, we identify two additional important features of the activated open state: slower nucleic acid binding kinetics and enhanced ATP-stimulated nucleic acid dissociation kinetics. Computational modeling based on empirical measurements of UPF1, UPF2, and RNA interaction kinetics predicts that the majority of UPF1-RNA binding and dissociation events in cells occur independently of UPF2 binding. We find that UPF1 mutants with either reduced or accelerated dissociation from RNA have NMD defects, whereas UPF1 mutants that are more dependent on UPF2 for catalytic activity remain active on well-established NMD targets. These findings support a model in which the kinetics of UPF1-mRNA interactions are important determinants of cellular NMD efficiency.
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Affiliation(s)
- Joseph H. Chapman
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Alice M. Youle
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Acadia L. Grimme
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Keir C. Neuman
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - J. Robert Hogg
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA
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4
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Matsuura-Suzuki E, Toh H, Iwasaki S. Human-rabbit Hybrid Translation System to Explore the Function of Modified Ribosomes. Bio Protoc 2023; 13:e4714. [PMID: 37456340 PMCID: PMC10339341 DOI: 10.21769/bioprotoc.4714] [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: 11/24/2022] [Revised: 03/15/2023] [Accepted: 06/19/2023] [Indexed: 07/18/2023] Open
Abstract
In vitro translation systems are a useful biochemical tool to research translational regulation. Although the preparation of translation-competent cell extracts from mammals has often been a challenge, the commercially available rabbit reticulocyte lysate (RRL) is an exception. However, its valid use, investigating the mechanism of translation machinery such as ribosomes in RRL, presents an analytic hurdle. To overcome this issue, the hybrid translation system, which is based on the supplementation of purified human ribosomes into ribosome-depleted RRL, has been developed. Here, we describe the step-by-step protocol of this system to study translation driven by ribosomes lacking post-translational modifications of the ribosomal protein. Moreover, we combined this approach with a previously developed reporter mRNA to assess the processivity of translation elongation. This protocol could be used to study the potency of heterologous ribosomes.
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Affiliation(s)
- Eriko Matsuura-Suzuki
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Hirotaka Toh
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Shintaro Iwasaki
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan
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5
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General Strategies for RNA X-ray Crystallography. Molecules 2023; 28:molecules28052111. [PMID: 36903357 PMCID: PMC10004510 DOI: 10.3390/molecules28052111] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 02/22/2023] [Accepted: 02/22/2023] [Indexed: 02/27/2023] Open
Abstract
An extremely small proportion of the X-ray crystal structures deposited in the Protein Data Bank are of RNA or RNA-protein complexes. This is due to three main obstacles to the successful determination of RNA structure: (1) low yields of pure, properly folded RNA; (2) difficulty creating crystal contacts due to low sequence diversity; and (3) limited methods for phasing. Various approaches have been developed to address these obstacles, such as native RNA purification, engineered crystallization modules, and incorporation of proteins to assist in phasing. In this review, we will discuss these strategies and provide examples of how they are used in practice.
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6
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Georgiou-Siafis SK, Miliotou AN, Ntenti C, Pappas IS, Papadopoulou LC. An Innovative PTD-IVT-mRNA Delivery Platform for CAR Immunotherapy of ErbB(+) Solid Tumor Neoplastic Cells. Biomedicines 2022; 10:2885. [PMID: 36359405 PMCID: PMC9687928 DOI: 10.3390/biomedicines10112885] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/02/2022] [Accepted: 11/04/2022] [Indexed: 11/25/2023] Open
Abstract
Chimeric antigen receptor (CAR) immunotherapy includes the genetic modification of immune cells to carry such a receptor and, thus, recognize cancer cell surface antigens. Viral transfection is currently the preferred method, but it carries the risk of off-target mutagenicity. Other transfection platforms have thus been proposed, such the in vitro transcribed (IVT)-mRNAs. In this study, we exploited our innovative, patented delivery platform to produce protein transduction domain (PTD)-IVT-mRNAs for the expression of CAR on NK-92 cells. CAR T1E-engineered NK-92 cells, harboring the sequence of T1E single-chain fragment variant (scFv) to recognize the ErbB receptor, bearing either CD28 or 4-1BB as co-stimulatory signaling domains, were prepared and assessed for their effectiveness in two different ErbB(+) cancer cell lines. Our results showed that the PTD-IVT-mRNA of CAR was safely transduced and expressed into NK-92 cells. CAR T1E-engineered NK-92 cells provoked high levels of cell death (25-33%) as effector cells against both HSC-3 (oral squamous carcinoma) and MCF-7 (breast metastatic adenocarcinoma) human cells in the co-incubation assays. In conclusion, the application of our novel PTD-IVT-mRNA delivery platform to NK-92 cells gave promising results towards future CAR immunotherapy approaches.
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Affiliation(s)
- Sofia K. Georgiou-Siafis
- Laboratory of Pharmacology, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Macedonia, Greece
- Laboratory of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Thessaly, 43100 Karditsa, Thessaly, Greece
| | - Androulla N. Miliotou
- Laboratory of Pharmacology, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Macedonia, Greece
- Department of Health Sciences, KES College, Nicosia 1055, Cyprus
| | - Charikleia Ntenti
- Laboratory of Pharmacology, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Macedonia, Greece
- 1st Laboratory of Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Macedonia, Greece
| | - Ioannis S. Pappas
- Laboratory of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Thessaly, 43100 Karditsa, Thessaly, Greece
| | - Lefkothea C. Papadopoulou
- Laboratory of Pharmacology, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Macedonia, Greece
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7
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Fritz SE, Ranganathan S, Wang CD, Hogg JR. An alternative UPF1 isoform drives conditional remodeling of nonsense-mediated mRNA decay. EMBO J 2022; 41:e108898. [PMID: 35403729 PMCID: PMC9108617 DOI: 10.15252/embj.2021108898] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 03/18/2022] [Accepted: 03/25/2022] [Indexed: 12/11/2022] Open
Abstract
The nonsense-mediated mRNA decay (NMD) pathway monitors translation termination in order to degrade transcripts with premature stop codons and regulate thousands of human genes. Here, we show that an alternative mammalian-specific isoform of the core NMD factor UPF1, termed UPF1LL , enables condition-dependent remodeling of NMD specificity. Previous studies indicate that the extension of a conserved regulatory loop in the UPF1LL helicase core confers a decreased propensity to dissociate from RNA upon ATP hydrolysis relative to UPF1SL , the major UPF1 isoform. Using biochemical and transcriptome-wide approaches, we find that UPF1LL can circumvent the protective RNA binding proteins PTBP1 and hnRNP L to preferentially bind and down-regulate transcripts with long 3'UTRs normally shielded from NMD. Unexpectedly, UPF1LL supports induction of NMD on new populations of substrate mRNAs in response to activation of the integrated stress response and impaired translation efficiency. Thus, while canonical NMD is abolished by moderate translational repression, UPF1LL activity is enhanced, offering the possibility to rapidly rewire NMD specificity in response to cellular stress.
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Affiliation(s)
- Sarah E Fritz
- Biochemistry and Biophysics CenterNational Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Soumya Ranganathan
- Biochemistry and Biophysics CenterNational Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Clara D Wang
- Biochemistry and Biophysics CenterNational Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - J Robert Hogg
- Biochemistry and Biophysics CenterNational Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMDUSA
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8
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Danchin A. In vivo, in vitro and in silico: an open space for the development of microbe-based applications of synthetic biology. Microb Biotechnol 2022; 15:42-64. [PMID: 34570957 PMCID: PMC8719824 DOI: 10.1111/1751-7915.13937] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 09/14/2021] [Indexed: 12/24/2022] Open
Abstract
Living systems are studied using three complementary approaches: living cells, cell-free systems and computer-mediated modelling. Progresses in understanding, allowing researchers to create novel chassis and industrial processes rest on a cycle that combines in vivo, in vitro and in silico studies. This design-build-test-learn iteration loop cycle between experiments and analyses combines together physiology, genetics, biochemistry and bioinformatics in a way that keeps going forward. Because computer-aided approaches are not directly constrained by the material nature of the entities of interest, we illustrate here how this virtuous cycle allows researchers to explore chemistry which is foreign to that present in extant life, from whole chassis to novel metabolic cycles. Particular emphasis is placed on the importance of evolution.
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Affiliation(s)
- Antoine Danchin
- Kodikos LabsInstitut Cochin24 rue du Faubourg Saint‐JacquesParis75014France
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9
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Gurzeler LA, Ziegelmüller J, Mühlemann O, Karousis ED. Production of human translation-competent lysates using dual centrifugation. RNA Biol 2021; 19:78-88. [PMID: 34965175 PMCID: PMC8815625 DOI: 10.1080/15476286.2021.2014695] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Protein synthesis is a central process in gene expression and the development of efficient in vitro translation systems has been the focus of scientific efforts for decades. The production of translation-competent lysates originating from human cells or tissues remains challenging, mainly due to the variability of cell lysis conditions. Here we present a robust and fast method based on dual centrifugation that allows for detergent-free cell lysis under controlled mechanical forces. We optimized the lysate preparation to yield cytoplasm-enriched extracts from human cells that efficiently translate mRNAs in a cap-dependent as well as in an IRES-mediated way. Reduction of the phosphorylation state of eIF2α using recombinant GADD34 and 2-aminopurine considerably boosts the protein output, reinforcing the potential of this method to produce recombinant proteins from human lysates.
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Affiliation(s)
- Lukas-Adrian Gurzeler
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Jana Ziegelmüller
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Oliver Mühlemann
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Evangelos D Karousis
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
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10
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Karousis ED, Gurzeler LA, Annibaldis G, Dreos R, Mühlemann O. Human NMD ensues independently of stable ribosome stalling. Nat Commun 2020; 11:4134. [PMID: 32807779 PMCID: PMC7431590 DOI: 10.1038/s41467-020-17974-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 07/20/2020] [Indexed: 12/18/2022] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is a translation-dependent RNA degradation pathway that is important for the elimination of faulty, and the regulation of normal, mRNAs. The molecular details of the early steps in NMD are not fully understood but previous work suggests that NMD activation occurs as a consequence of ribosome stalling at the termination codon (TC). To test this hypothesis, we established an in vitro translation-coupled toeprinting assay based on lysates from human cells that allows monitoring of ribosome occupancy at the TC of reporter mRNAs. In contrast to the prevailing NMD model, our in vitro system reveals similar ribosomal occupancy at the stop codons of NMD-sensitive and NMD-insensitive reporter mRNAs. Moreover, ribosome profiling reveals a similar density of ribosomes at the TC of endogenous NMD-sensitive and NMD-insensitive mRNAs in vivo. Together, these data show that NMD activation is not accompanied by stable stalling of ribosomes at TCs. Nonsense-mediated mRNA decay (NMD) was thought to ensue when ribosomes fail to terminate translation properly. However, the authors observe similar ribosome occupancy at stop codons of NMD sensitive and insensitive mRNAs, showing that human NMD is not activated by stable ribosome stalling as previously suggested.
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Affiliation(s)
- Evangelos D Karousis
- Department of Chemistry and Biochemistry, University of Bern, CH-3012, Bern, Switzerland
| | - Lukas-Adrian Gurzeler
- Department of Chemistry and Biochemistry, University of Bern, CH-3012, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3012, Bern, Switzerland
| | - Giuditta Annibaldis
- Department of Chemistry and Biochemistry, University of Bern, CH-3012, Bern, Switzerland
| | - René Dreos
- Center for Integrative Genomics, Université de Lausanne, CH-1015, Lausanne, Switzerland
| | - Oliver Mühlemann
- Department of Chemistry and Biochemistry, University of Bern, CH-3012, Bern, Switzerland.
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11
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Fritz SE, Ranganathan S, Wang CD, Hogg JR. The RNA-binding protein PTBP1 promotes ATPase-dependent dissociation of the RNA helicase UPF1 to protect transcripts from nonsense-mediated mRNA decay. J Biol Chem 2020; 295:11613-11625. [PMID: 32571872 DOI: 10.1074/jbc.ra120.013824] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 06/18/2020] [Indexed: 01/02/2023] Open
Abstract
The sequence-specific RNA-binding proteins PTBP1 (polypyrimidine tract-binding protein 1) and HNRNP L (heterogeneous nuclear ribonucleoprotein L) protect mRNAs from nonsense-mediated decay (NMD) by preventing the UPF1 RNA helicase from associating with potential decay targets. Here, by analyzing in vitro helicase activity, dissociation of UPF1 from purified mRNPs, and transcriptome-wide UPF1 RNA binding, we present the mechanistic basis for inhibition of NMD by PTBP1. Unlike mechanisms of RNA stabilization that depend on direct competition for binding sites among protective RNA-binding proteins and decay factors, PTBP1 promotes displacement of UPF1 already bound to potential substrates. Our results show that PTBP1 directly exploits the tendency of UPF1 to release RNA upon ATP binding and hydrolysis. We further find that UPF1 sensitivity to PTBP1 is coordinated by a regulatory loop in domain 1B of UPF1. We propose that the UPF1 regulatory loop and protective proteins control kinetic proofreading of potential NMD substrates, presenting a new model for RNA helicase regulation and target selection in the NMD pathway.
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Affiliation(s)
- Sarah E Fritz
- Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, Maryland, USA
| | - Soumya Ranganathan
- Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, Maryland, USA
| | - Clara D Wang
- Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, Maryland, USA
| | - J Robert Hogg
- Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, Maryland, USA
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12
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