1
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Yi G, Ye M, Carrique L, El-Sagheer A, Brown T, Norbury CJ, Zhang P, Gilbert RJC. Structural basis for activity switching in polymerases determining the fate of let-7 pre-miRNAs. Nat Struct Mol Biol 2024:10.1038/s41594-024-01357-9. [PMID: 39054354 DOI: 10.1038/s41594-024-01357-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 06/17/2024] [Indexed: 07/27/2024]
Abstract
Tumor-suppressor let-7 pre-microRNAs (miRNAs) are regulated by terminal uridylyltransferases TUT7 and TUT4 that either promote let-7 maturation by adding a single uridine nucleotide to the pre-miRNA 3' end or mark them for degradation by the addition of multiple uridines. Oligo-uridylation is increased in cells by enhanced TUT7/4 expression and especially by the RNA-binding pluripotency factor LIN28A. Using cryogenic electron microscopy, we captured high-resolution structures of active forms of TUT7 alone, of TUT7 plus pre-miRNA and of both TUT7 and TUT4 bound with pre-miRNA and LIN28A. Our structures reveal that pre-miRNAs engage the enzymes in fundamentally different ways depending on the presence of LIN28A, which clamps them onto the TUTs to enable processive 3' oligo-uridylation. This study reveals the molecular basis for mono- versus oligo-uridylation by TUT7/4, as determined by the presence of LIN28A, and thus their mechanism of action in the regulation of cell fate and in cancer.
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Affiliation(s)
- Gangshun Yi
- Division of Structural Biology, Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Calleva Centre for Evolution and Human Science, Magdalen College, Oxford, UK
| | - Mingda Ye
- Centre for Medicines Discovery, University of Oxford, Oxford, UK
| | - Loic Carrique
- Division of Structural Biology, Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Afaf El-Sagheer
- Chemistry Research Laboratory, University of Oxford, Oxford, UK
- Institute for Life Sciences, University of Southampton Highfield Campus, Southampton, UK
| | - Tom Brown
- Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Chris J Norbury
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Peijun Zhang
- Division of Structural Biology, Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
- Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford, UK
| | - Robert J C Gilbert
- Division of Structural Biology, Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Calleva Centre for Evolution and Human Science, Magdalen College, Oxford, UK.
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2
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Yamashita S, Tomita K. Mechanism of U6 snRNA oligouridylation by human TUT1. Nat Commun 2023; 14:4686. [PMID: 37563152 PMCID: PMC10415362 DOI: 10.1038/s41467-023-40420-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 07/27/2023] [Indexed: 08/12/2023] Open
Abstract
U6 snRNA is a catalytic RNA responsible for pre-mRNA splicing reactions and undergoes various post-transcriptional modifications during its maturation process. The 3'-oligouridylation of U6 snRNA by the terminal uridylyltransferase, TUT1, provides the Lsm-binding site in U6 snRNA for U4/U6 di-snRNP formation and this ensures pre-mRNA splicing. Here, we present the crystal structure of human TUT1 (hTUT1) complexed with U6 snRNA, representing the post-uridylation of U6 snRNA by hTUT1. The N-terminal ZF-RRM and catalytic palm clamp the single-stranded AUA motif between the 5'-short stem and the 3'-telestem of U6 snRNA, and the ZF-RRM specifically recognizes the AUA motif. The ZF and the fingers hold the telestem, and the 3'-end of U6 snRNA is placed in the catalytic pocket of the palm for oligouridylation. The oligouridylation of U6 snRNA depends on the internal four-adenosine tract in the 5'-part of the telestem of U6 snRNA, and hTUT1 adds uridines until the internal adenosine tract can form base-pairs with the 3'-oligouridine tract. Together, the recognition of the specific structure and sequence of U6 snRNA by the multi-domain TUT1 protein and the intrinsic sequence and structure of U6 snRNA ensure the oligouridylation of U6 snRNA.
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Affiliation(s)
- Seisuke Yamashita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan
| | - Kozo Tomita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, 277-8562, Japan.
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3
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Hu Q, Yang H, Li M, Zhu L, Lv M, Li F, Zhang Z, Ren G, Gong Q. Molecular mechanism underlying the di-uridylation activity of Arabidopsis TUTase URT1. Nucleic Acids Res 2022; 50:10614-10625. [PMID: 36177876 PMCID: PMC9561377 DOI: 10.1093/nar/gkac839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/09/2022] [Accepted: 09/19/2022] [Indexed: 11/14/2022] Open
Abstract
In Arabidopsis, HESO1 and URT1 act cooperatively on unmethylated miRNA and mRNA uridylation to induce their degradation. Their collaboration significantly impacts RNA metabolism in plants. However, the molecular mechanism determining the functional difference and complementarity of these two enzymes remains unclear. We previously solved the three-dimensional structure of URT1 in the absence and presence of UTP. In this study, we further determined the structure of URT1 in complex with a 5′-AAAU-3′ RNA stretch that mimics the post-catalytic state of the mRNA poly(A) tail after the addition of the first uridine. Structural analysis and enzymatic assays revealed that L527 and Y592 endow URT1 with a preference to interact with purine over pyrimidine at the -1 RNA binding position, thus controlling the optimal number of uridine added to the 3′ extremity of poly(A) as two. In addition, we observed that a large-scale conformational rearrangement in URT1 occurs upon binding with RNA from an ‘open’ to a ‘closed’ state. Molecular dynamic simulation supports an open-closed conformational selection mechanism employed by URT1 to interact with RNA substrates and maintain distributive enzymatic activity. Based on the above results, a model regarding the catalytic cycle of URT1 is proposed to explain its di-uridylation activity.
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Affiliation(s)
- Qian Hu
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Huiru Yang
- State Key Laboratory of Genetic Engineering, Zhangjiang mRNA Innovation and Translation Center, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Mingwei Li
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Lingru Zhu
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Mengqi Lv
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Fudong Li
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
| | - Zhiyong Zhang
- Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, P.R. China
| | - Guodong Ren
- State Key Laboratory of Genetic Engineering, Zhangjiang mRNA Innovation and Translation Center, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Qingguo Gong
- Department of Clinical Laboratory, The First Affiliated Hospital of USTC, Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Biomedical Sciences and Health Laboratory of Anhui Province, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, 230027 Hefei, P.R. China
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4
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Bencurova E, Shityakov S, Schaack D, Kaltdorf M, Sarukhanyan E, Hilgarth A, Rath C, Montenegro S, Roth G, Lopez D, Dandekar T. Nanocellulose Composites as Smart Devices With Chassis, Light-Directed DNA Storage, Engineered Electronic Properties, and Chip Integration. Front Bioeng Biotechnol 2022; 10:869111. [PMID: 36105598 PMCID: PMC9465592 DOI: 10.3389/fbioe.2022.869111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 06/24/2022] [Indexed: 11/13/2022] Open
Abstract
The rapid development of green and sustainable materials opens up new possibilities in the field of applied research. Such materials include nanocellulose composites that can integrate many components into composites and provide a good chassis for smart devices. In our study, we evaluate four approaches for turning a nanocellulose composite into an information storage or processing device: 1) nanocellulose can be a suitable carrier material and protect information stored in DNA. 2) Nucleotide-processing enzymes (polymerase and exonuclease) can be controlled by light after fusing them with light-gating domains; nucleotide substrate specificity can be changed by mutation or pH change (read-in and read-out of the information). 3) Semiconductors and electronic capabilities can be achieved: we show that nanocellulose is rendered electronic by iodine treatment replacing silicon including microstructures. Nanocellulose semiconductor properties are measured, and the resulting potential including single-electron transistors (SET) and their properties are modeled. Electric current can also be transported by DNA through G-quadruplex DNA molecules; these as well as classical silicon semiconductors can easily be integrated into the nanocellulose composite. 4) To elaborate upon miniaturization and integration for a smart nanocellulose chip device, we demonstrate pH-sensitive dyes in nanocellulose, nanopore creation, and kinase micropatterning on bacterial membranes as well as digital PCR micro-wells. Future application potential includes nano-3D printing and fast molecular processors (e.g., SETs) integrated with DNA storage and conventional electronics. This would also lead to environment-friendly nanocellulose chips for information processing as well as smart nanocellulose composites for biomedical applications and nano-factories.
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Affiliation(s)
- Elena Bencurova
- Functional Genomics and Systems Biology Group, Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Sergey Shityakov
- Laboratory of Chemoinformatics, Infochemistry Scientific Center, ITMO University, Saint Petersburg, Russia
| | - Dominik Schaack
- Functional Genomics and Systems Biology Group, Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Martin Kaltdorf
- Functional Genomics and Systems Biology Group, Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Edita Sarukhanyan
- Functional Genomics and Systems Biology Group, Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Alexander Hilgarth
- Aerospace Information Technology, University of Würzburg, Würzburg, Germany
| | - Christin Rath
- Laboratory for Microarray Copying, Center for Biological Systems Analysis (ZBSA), University of Freiburg, Freiburg, Germany
| | - Sergio Montenegro
- Aerospace Information Technology, University of Würzburg, Würzburg, Germany
| | - Günter Roth
- Laboratory for Microarray Copying, Center for Biological Systems Analysis (ZBSA), University of Freiburg, Freiburg, Germany
- BioCopy GmbH, Emmendingen, Germany
| | - Daniel Lopez
- Centro Nacional de Biotecnologia CNB, Universidad Autonoma de Madrid, Madrid, Spain
| | - Thomas Dandekar
- Functional Genomics and Systems Biology Group, Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
- Structural and Computational Biology, European Molecular Biology Laboratory, Heidelberg, Germany
- *Correspondence: Thomas Dandekar,
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5
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Vo JM, Mulroney L, Quick-Cleveland J, Jain M, Akeson M, Ares M. Synthesis of modified nucleotide polymers by the poly(U) polymerase Cid1: application to direct RNA sequencing on nanopores. RNA (NEW YORK, N.Y.) 2021; 27:1497-1511. [PMID: 34446532 PMCID: PMC8594468 DOI: 10.1261/rna.078898.121] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 08/23/2021] [Indexed: 05/27/2023]
Abstract
Understanding transcriptomes requires documenting the structures, modifications, and abundances of RNAs as well as their proximity to other molecules. The methods that make this possible depend critically on enzymes (including mutant derivatives) that act on nucleic acids for capturing and sequencing RNA. We tested two 3' nucleotidyl transferases, Saccharomyces cerevisiae poly(A) polymerase and Schizosaccharomyces pombe Cid1, for the ability to add base and sugar modified rNTPs to free RNA 3' ends, eventually focusing on Cid1. Although unable to polymerize ΨTP or 1meΨTP, Cid1 can use 5meUTP and 4thioUTP. Surprisingly, Cid1 can use inosine triphosphate to add poly(I) to the 3' ends of a wide variety of RNA molecules. Most poly(A) mRNAs efficiently acquire a uniform tract of about 50 inosine residues from Cid1, whereas non-poly(A) RNAs acquire longer, more heterogeneous tails. Here we test these activities for use in direct RNA sequencing on nanopores, and find that Cid1-mediated poly(I)-tailing permits detection and quantification of both mRNAs and non-poly(A) RNAs simultaneously, as well as enabling the analysis of nascent RNAs associated with RNA polymerase II. Poly(I) produces a different current trace than poly(A), enabling recognition of native RNA 3' end sequence lost by in vitro poly(A) addition. Addition of poly(I) by Cid1 offers a broadly useful alternative to poly(A) capture for direct RNA sequencing on nanopores.
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Affiliation(s)
- Jenny Mai Vo
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064, USA
| | - Logan Mulroney
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, California 95064, USA
| | - Jen Quick-Cleveland
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064, USA
| | - Miten Jain
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, California 95064, USA
| | - Mark Akeson
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, California 95064, USA
| | - Manuel Ares
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064, USA
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6
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Chung CZ, Balasuriya N, Siddika T, Frederick MI, Heinemann IU. Gld2 activity and RNA specificity is dynamically regulated by phosphorylation and interaction with QKI-7. RNA Biol 2021; 18:397-408. [PMID: 34288801 DOI: 10.1080/15476286.2021.1952540] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
In the cell, RNA abundance is dynamically controlled by transcription and decay rates. Posttranscriptional nucleotide addition at the RNA 3' end is a means of regulating mRNA and RNA stability and activity, as well as marking RNAs for degradation. The human nucleotidyltransferase Gld2 polyadenylates mRNAs and monoadenylates microRNAs, leading to an increase in RNA stability. The broad substrate range of Gld2 and its role in controlling RNA stability make the regulation of Gld2 activity itself imperative. Gld2 activity can be regulated by post-translational phosphorylation via the oncogenic kinase Akt1 and other kinases, leading to either increased or almost abolished enzymatic activity, and here we confirm that Akt1 phosphorylates Gld2 in a cellular context. Another means to control Gld2 RNA specificity and activity is the interaction with RNA binding proteins. Known interactors are QKI-7 and CPEB, which recruit Gld2 to specific miRNAs and mRNAs. We investigate the interplay between five phosphorylation sites in the N-terminal domain of Gld2 and three RNA binding proteins. We found that the activity and RNA specificity of Gld2 is dynamically regulated by this network. Binding of QKI-7 or phosphorylation at S62 relieves the autoinhibitory function of the Gld2 N-terminal domain. Binding of QKI-7 to a short peptide sequence within the N-terminal domain can also override the deactivation caused by Akt1 phosphorylation at S116. Our data revealed that Gld2 substrate specificity and activity can be dynamically regulated to match the cellular need of RNA stabilization and turnover.
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Affiliation(s)
- Christina Z Chung
- Department of Biochemistry, Schulich School of Medicine and Dentistry, the University of Western Ontario, London, Canada
| | - Nileeka Balasuriya
- Department of Biochemistry, Schulich School of Medicine and Dentistry, the University of Western Ontario, London, Canada
| | - Tarana Siddika
- Department of Biochemistry, Schulich School of Medicine and Dentistry, the University of Western Ontario, London, Canada
| | - Mallory I Frederick
- Department of Biochemistry, Schulich School of Medicine and Dentistry, the University of Western Ontario, London, Canada
| | - Ilka U Heinemann
- Department of Biochemistry, Schulich School of Medicine and Dentistry, the University of Western Ontario, London, Canada
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7
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Malik D, Kobyłecki K, Krawczyk P, Poznański J, Jakielaszek A, Napiórkowska A, Dziembowski A, Tomecki R, Nowotny M. Structure and mechanism of CutA, RNA nucleotidyl transferase with an unusual preference for cytosine. Nucleic Acids Res 2020; 48:9387-9405. [PMID: 32785623 PMCID: PMC7498324 DOI: 10.1093/nar/gkaa647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/14/2020] [Accepted: 07/27/2020] [Indexed: 11/12/2022] Open
Abstract
Template-independent terminal ribonucleotide transferases (TENTs) catalyze the addition of nucleotide monophosphates to the 3′-end of RNA molecules regulating their fate. TENTs include poly(U) polymerases (PUPs) with a subgroup of 3′ CUCU-tagging enzymes, such as CutA in Aspergillus nidulans. CutA preferentially incorporates cytosines, processively polymerizes only adenosines and does not incorporate or extend guanosines. The basis of this peculiar specificity remains to be established. Here, we describe crystal structures of the catalytic core of CutA in complex with an incoming non-hydrolyzable CTP analog and an RNA with three adenosines, along with biochemical characterization of the enzyme. The binding of GTP or a primer with terminal guanosine is predicted to induce clashes between 2-NH2 of the guanine and protein, which would explain why CutA is unable to use these ligands as substrates. Processive adenosine polymerization likely results from the preferential binding of a primer ending with at least two adenosines. Intriguingly, we found that the affinities of CutA for the CTP and UTP are very similar and the structures did not reveal any apparent elements for specific NTP binding. Thus, the properties of CutA likely result from an interplay between several factors, which may include a conformational dynamic process of NTP recognition.
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Affiliation(s)
- Deepshikha Malik
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw 02-109, Poland
| | - Kamil Kobyłecki
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, Warsaw 02-106, Poland
| | - Paweł Krawczyk
- Laboratory of RNA Biology, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw 02-109, Poland
| | - Jarosław Poznański
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, Warsaw 02-106, Poland
| | - Aleksandra Jakielaszek
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw 02-109, Poland
| | - Agnieszka Napiórkowska
- Structural Biology Center, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw 02-109, Poland
| | - Andrzej Dziembowski
- Laboratory of RNA Biology, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw 02-109, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Pawinskiego 5a, Warsaw 02-106, Poland
| | - Rafał Tomecki
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, Warsaw 02-106, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Pawinskiego 5a, Warsaw 02-106, Poland
| | - Marcin Nowotny
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw 02-109, Poland
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8
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George JT, Srivatsan SG. Responsive fluorescent nucleotides serve as efficient substrates to probe terminal uridylyl transferase. Chem Commun (Camb) 2020; 56:12319-12322. [PMID: 32939524 PMCID: PMC7611084 DOI: 10.1039/d0cc05092j] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We repurposed a terminal uridylyl transferase enzyme to site-specifically label RNA with microenvironment sensing fluorescent nucleotide mimics, which in turn provided direct read-outs to estimate the binding affinities of the enzyme to RNA and nucleotide substrates. This enzyme-probe system provides insights into the catalytic cycle, and can facilitate the development of discovery platforms to identify robust enzyme inhibitors.
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Affiliation(s)
- Jerrin Thomas George
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Dr Homi Bhabha Road, Pashan, Pune 411008, India.
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9
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George JT, Azhar M, Aich M, Sinha D, Ambi UB, Maiti S, Chakraborty D, Srivatsan SG. Terminal Uridylyl Transferase Mediated Site-Directed Access to Clickable Chromatin Employing CRISPR-dCas9. J Am Chem Soc 2020; 142:13954-13965. [PMID: 32658470 PMCID: PMC7611130 DOI: 10.1021/jacs.0c06541] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Locus-specific interrogation of target genes employing functional probes such as proteins and small molecules is paramount in decoding the molecular basis of gene function and designing tools to modulate its downstream effects. In this context, CRISPR-based gene editing and targeting technologies have proved tremendously useful, as they can be programmed to target any gene of interest by simply changing the sequence of the single guide RNA (sgRNA). Although these technologies are widely utilized in recruiting genetically encoded functional proteins, display of small molecules using CRISPR system is not well developed due to the lack of adequate techniques. Here, we have devised an innovative technology called sgRNA-Click (sgR-CLK) that harnesses the power of bioorthogonal click chemistry for remodeling guide RNA to display synthetic molecules on target genes. sgR-CLK employs a novel posttranscriptional chemoenzymatic labeling platform wherein a terminal uridylyl transferase (TUTase) was repurposed to generate clickable sgRNA of choice by site-specific tailoring of multiple azide-modified nucleotide analogues at the 3' end. The presence of a minimally invasive azide handle assured that the sgRNAs are indeed functional. Notably, an azide-tailed sgRNA targeting the telomeric repeat served as a Trojan horse on the CRISPR-dCas9 system to guide synthetic tags (biotin) site-specifically on chromatin employing copper-catalyzed or strain-promoted click reactions. Taken together, sgR-CLK presents a significant advancement on the utility of bioorthogonal chemistry, TUTase, and the CRISPR toolbox, which could offer a simplified solution for site-directed display of small molecule probes and diagnostic tools on target genes.
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Affiliation(s)
- Jerrin Thomas George
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune Dr. Homi Bhabha Road, Pune 411008, India
| | | | | | | | - Uddhav B Ambi
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune Dr. Homi Bhabha Road, Pune 411008, India
| | - Souvik Maiti
- Institute of Genomics and Integrative Biology (IGIB)-National Chemical Laboratory (NCL) Joint Center, Council of Scientific and Industrial Research-NCL, Pune 411008, India
| | | | - Seergazhi G Srivatsan
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune Dr. Homi Bhabha Road, Pune 411008, India
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10
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Liudkovska V, Dziembowski A. Functions and mechanisms of RNA tailing by metazoan terminal nucleotidyltransferases. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1622. [PMID: 33145994 PMCID: PMC7988573 DOI: 10.1002/wrna.1622] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/25/2020] [Accepted: 06/26/2020] [Indexed: 12/28/2022]
Abstract
Termini often determine the fate of RNA molecules. In recent years, 3' ends of almost all classes of RNA species have been shown to acquire nontemplated nucleotides that are added by terminal nucleotidyltransferases (TENTs). The best-described role of 3' tailing is the bulk polyadenylation of messenger RNAs in the cell nucleus that is catalyzed by canonical poly(A) polymerases (PAPs). However, many other enzymes that add adenosines, uridines, or even more complex combinations of nucleotides have recently been described. This review focuses on metazoan TENTs, which are either noncanonical PAPs or terminal uridylyltransferases with varying processivity. These enzymes regulate RNA stability and RNA functions and are crucial in early development, gamete production, and somatic tissues. TENTs regulate gene expression at the posttranscriptional level, participate in the maturation of many transcripts, and protect cells against viral invasion and the transposition of repetitive sequences. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition RNA Processing > 3' End Processing RNA Turnover and Surveillance > Regulation of RNA Stability.
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Affiliation(s)
- Vladyslava Liudkovska
- Laboratory of RNA Biology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Andrzej Dziembowski
- Laboratory of RNA Biology, International Institute of Molecular and Cell Biology, Warsaw, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland
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11
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A tale of non-canonical tails: gene regulation by post-transcriptional RNA tailing. Nat Rev Mol Cell Biol 2020; 21:542-556. [PMID: 32483315 DOI: 10.1038/s41580-020-0246-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2020] [Indexed: 01/06/2023]
Abstract
RNA tailing, or the addition of non-templated nucleotides to the 3' end of RNA, is the most frequent and conserved type of RNA modification. The addition of tails and their composition reflect RNA maturation stages and have important roles in determining the fate of the modified RNAs. Apart from canonical poly(A) polymerases, which add poly(A) tails to mRNAs in a transcription-coupled manner, a family of terminal nucleotidyltransferases (TENTs), including terminal uridylyltransferases (TUTs), modify RNAs post-transcriptionally to control RNA stability and activity. The human genome encodes 11 different TENTs with distinct substrate specificity, intracellular localization and tissue distribution. In this Review, we discuss recent advances in our understanding of non-canonical RNA tails, with a focus on the functions of human TENTs, which include uridylation, mixed tailing and post-transcriptional polyadenylation of mRNAs, microRNAs and other types of non-coding RNA.
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12
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Zhu L, Hu Q, Cheng L, Jiang Y, Lv M, Liu Y, Li F, Shi Y, Gong Q. Crystal structure of Arabidopsis terminal uridylyl transferase URT1. Biochem Biophys Res Commun 2020; 524:490-496. [PMID: 32008746 DOI: 10.1016/j.bbrc.2020.01.124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 01/22/2020] [Indexed: 11/19/2022]
Abstract
3' uridylation is an essential modification associated with coding and noncoding RNA degradation in eukaryotes. In Arabidopsis, HESO1 was first identified as the major nucleotidyl transferase that uridylates most unmethylated miRNAs, and URT1 was later reported to play a redundant but important role in miRNA uridylation when HESO1 is absent. Two enzymes work sequentially and collaboratively to tail different forms of the same miRNAs in vivo. For mRNA, however, URT1 becomes the main enzyme to uridylate the majority of mRNA and repairs their deadenylated ends to restore the binding site for Poly(A) Binding Protein (PABP). HESO1, on the other hand, targets mostly the mRNAs with very short oligo(A) tails and fails in fulfilling the same task. To understand the structural basis these two functional homologues possess for their different substrate preferences and catalytic behaviors, we first determined the crystal structures of URT1 in the absence and presence of UTP. Our structures, together with functional assay and sequence analysis, indicated that URT1 has a conserved UTP-recognition mechanism analogue to the terminal uridylyl transferases from other species whereas HESO1 may evolve separately to recognize UTP in a different way. Moreover, URT1 N552 may be an important residue in interacting with 3' nucleotide of RNA substrate. The URT1 structure we determined represents the first structure of uridylyl transferase from plants, shedding light on the mechanisms of URT1/HESO1-dependent RNA metabolism.
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Affiliation(s)
- Lingru Zhu
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China
| | - Qian Hu
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China
| | - Lin Cheng
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China
| | - Yiyang Jiang
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China
| | - Mengqi Lv
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China
| | - Yongrui Liu
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China
| | - Fudong Li
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China
| | - Yunyu Shi
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China
| | - Qingguo Gong
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230027, China.
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13
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Ukwatta KM, Lawrence JL, Wijayarathne CD. Antimicrobial, anti-cancer, anti-filarial and anti-inflammatory activities of Cowabenzophenone A extracted from the endophytic fungus Aspergillus terreus isolated from a mangrove plant Bruguiera gymnorrhyza. Mycology 2019; 11:297-305. [PMID: 33329925 PMCID: PMC7723023 DOI: 10.1080/21501203.2019.1707722] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Cowabenzophenone A was isolated from an endophytic fungus Aspergillus terreus isolated from a mangrove plant Bruguiera gymnorrhyza. The structure was determined by analysis of 1D and 2D NMR spectra and mass spectrometric data as a tetracyclo[7.3.3.33,11.03,7]tetradecane-2,12,14-trione skeleton. When the compound was tested in vitro for its ability to inhibit inflammations, α-glucosidase inhibitory activities and its antimicrobial properties, it showed an anti-inflammatory activity amounting to an IC50 of 12.1 µg/mL, α-glucosidase inhibitory activity, with IC50 values of 7.8 ± 0.5 μM, and antibacterial activity against Bacillus subtilis TISTR 088, and Bacillus cereus TISTR 688 with MIC values of 1 μg/mL and 2 μg/mL respectively. The compound showed cytotoxicity against HCT 116 colon cancer cell line with an IC50 value of 10.1 ?M, and also showed a considerably high potential towards anti-filarial activities by resulting MIC, IC50 and LC50 values of 0.358 ± 0.02 mg/mL, 0.708 ± 0.021 mg/mL and 3.89 ± 0.18 mg/mL, respectively, in comparison to the standard drug Ivermectin (IVM).
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Affiliation(s)
- Kushan M Ukwatta
- Department of Chemistry, University of Colombo, Colombo, Sri Lanka.,Departments of Chemistry and Earth, Ocean and Atmospheric Science, University of British Columbia (UBC), Vancouver, Canada
| | | | - C D Wijayarathne
- Department of Chemistry, University of Colombo, Colombo, Sri Lanka
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14
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Cheng L, Li F, Jiang Y, Yu H, Xie C, Shi Y, Gong Q. Structural insights into a unique preference for 3' terminal guanine of mirtron in Drosophila TUTase tailor. Nucleic Acids Res 2019; 47:495-508. [PMID: 30407553 PMCID: PMC6326804 DOI: 10.1093/nar/gky1116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 10/23/2018] [Indexed: 01/19/2023] Open
Abstract
Terminal uridylyl transferase (TUTase) is one type of enzyme that modifies RNA molecules by facilitating the post-transcriptional addition of uridyl ribonucleotides to their 3' ends. Recent researches have reported that Drosophila TUTase, Tailor, exhibits an intrinsic preference for RNA substrates ending in 3'G, distinguishing it from any other known TUTases. Through this unique feature, Tailor plays a crucial role as the repressor in the biogenesis pathway of splicing-derived mirtron pre-miRNAs. Here we describe crystal structures of core catalytic domain of Tailor and its complexes with RNA stretches 5'-AGU-3' and 5'-AGUU-3'. We demonstrate that R327 and N347 are two key residues contributing cooperatively to Tailor's preference for 3'G, and R327 may play an extra role in facilitating the extension of polyuridylation chain. We also demonstrate that conformational stability of the exit of RNA-binding groove also contributes significantly to Tailor's activity. Overall, our work reveals useful insights to explain why Drosophila Tailor can preferentially select RNA substrates ending in 3'G and provides important values for further understanding the biological significances of biogenesis pathway of mirtron in flies.
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Affiliation(s)
- Lin Cheng
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230027, China
| | - Fudong Li
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230027, China
| | - Yiyang Jiang
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230027, China
| | - Hailong Yu
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230027, China
| | - Changlin Xie
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230027, China.,High Magnet Field Laboratory, Chinese Academy of Science, 50 Shushanhu Road, Hefei, Anhui 230031, China
| | - Yunyu Shi
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230027, China
| | - Qingguo Gong
- Hefei National Laboratory for Physical Science at the Microscale, School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230027, China
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15
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Kroupova A, Ivascu A, Reimão-Pinto MM, Ameres SL, Jinek M. Structural basis for acceptor RNA substrate selectivity of the 3' terminal uridylyl transferase Tailor. Nucleic Acids Res 2019; 47:1030-1042. [PMID: 30462292 PMCID: PMC6344859 DOI: 10.1093/nar/gky1164] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 11/12/2018] [Indexed: 11/16/2022] Open
Abstract
Non-templated 3′-uridylation of RNAs has emerged as an important mechanism for regulating the processing, stability and biological function of eukaryotic transcripts. In Drosophila, oligouridine tailing by the terminal uridylyl transferase (TUTase) Tailor of numerous RNAs induces their degradation by the exonuclease Dis3L2, which serves functional roles in RNA surveillance and mirtron RNA biogenesis. Tailor preferentially uridylates RNAs terminating in guanosine or uridine nucleotides but the structural basis underpinning its RNA substrate selectivity is unknown. Here, we report crystal structures of Tailor bound to a donor substrate analog or mono- and oligouridylated RNA products. These structures reveal specific amino acid residues involved in donor and acceptor substrate recognition, and complementary biochemical assays confirm the critical role of an active site arginine in conferring selectivity toward 3′-guanosine terminated RNAs. Notably, conservation of these active site features suggests that other eukaryotic TUTases, including mammalian TUT4 and TUT7, might exhibit similar, hitherto unknown, substrate selectivity. Together, these studies provide critical insights into the specificity of 3′-uridylation in eukaryotic post-transcriptional gene regulation.
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Affiliation(s)
- Alena Kroupova
- Department of Biochemistry, University of Zurich, Zurich 8057, Switzerland
| | - Anastasia Ivascu
- Department of Biochemistry, University of Zurich, Zurich 8057, Switzerland
| | - Madalena M Reimão-Pinto
- Institute of Molecular Biotechnology, IMBA, Vienna Biocenter Campus (VBC), Vienna 1030, Austria
| | - Stefan L Ameres
- Institute of Molecular Biotechnology, IMBA, Vienna Biocenter Campus (VBC), Vienna 1030, Austria
| | - Martin Jinek
- Department of Biochemistry, University of Zurich, Zurich 8057, Switzerland
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16
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Preston MA, Porter DF, Chen F, Buter N, Lapointe CP, Keles S, Kimble J, Wickens M. Unbiased screen of RNA tailing activities reveals a poly(UG) polymerase. Nat Methods 2019; 16:437-445. [PMID: 30988468 PMCID: PMC6613791 DOI: 10.1038/s41592-019-0370-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 02/24/2019] [Accepted: 03/05/2019] [Indexed: 12/22/2022]
Abstract
Ribonucleotidyl transferases (rNTases) add untemplated ribonucleotides to diverse RNAs. We have developed TRAID-seq, a screening strategy in Saccharomyces cerevisiae to identify sequences added to a reporter RNA at single-nucleotide resolution by overexpressed candidate enzymes from different organisms. The rNTase activities of 22 previously unexplored enzymes were determined. In addition to poly(A)- and poly(U)-adding enzymes, we identified a cytidine-adding enzyme that is likely to be part of a two-enzyme system that adds CCA to tRNAs in a eukaryote; a nucleotidyl transferase that adds nucleotides to RNA without apparent nucleotide preference; and a poly(UG) polymerase, Caenorhabditis elegans MUT-2, that adds alternating uridine and guanosine nucleotides to form poly(UG) tails. MUT-2 is known to be required for certain forms of RNA silencing, and mutants of the enzyme that result in defective silencing did not add poly(UG) tails in our assay. We propose that MUT-2 poly(UG) polymerase activity is required to promote genome integrity and RNA silencing.
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Affiliation(s)
- Melanie A Preston
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
- Promega Corporation, Madison, WI, USA
| | - Douglas F Porter
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
- Program in Epithelial Biology, Stanford University Medical School, Stanford, CA, USA
| | - Fan Chen
- Department of Statistics, University of Wisconsin-Madison, Madison, WI, USA
| | - Natascha Buter
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
- Promega Corporation, Madison, WI, USA
| | - Christopher P Lapointe
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
- Department of Structural Biology, Stanford University, Stanford, CA, USA
| | - Sunduz Keles
- Department of Statistics, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, WI, USA
| | - Judith Kimble
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA
- Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Marvin Wickens
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA.
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17
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Crystal structure of the Lin28-interacting module of human terminal uridylyltransferase that regulates let-7 expression. Nat Commun 2019; 10:1960. [PMID: 31036859 PMCID: PMC6488673 DOI: 10.1038/s41467-019-09966-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 04/10/2019] [Indexed: 01/02/2023] Open
Abstract
Lin28-dependent oligo-uridylylation of precursor let-7 (pre-let-7) by terminal uridylyltransferase 4/7 (TUT4/7) represses let-7 expression by blocking Dicer processing, and regulates cell differentiation and proliferation. The interaction between the Lin28:pre-let-7 complex and the N-terminal Lin28-interacting module (LIM) of TUT4/7 is required for pre-let-7 oligo-uridylylation by the C-terminal catalytic module (CM) of TUT4/7. Here, we report crystallographic and biochemical analyses of the LIM of human TUT4. The LIM consists of the N-terminal Cys2His2-type zinc finger (ZF) and the non-catalytic nucleotidyltransferase domain (nc-NTD). The ZF of LIM adopts a distinct structural domain, and its structure is homologous to those of double-stranded RNA binding zinc fingers. The interaction between the ZF and pre-let-7 stabilizes the Lin28:pre-let-7:TUT4 ternary complex, and enhances the oligo-uridylylation reaction by the CM. Thus, the ZF in LIM and the zinc-knuckle in the CM, which interacts with the oligo-uridylylated tail, together facilitate Lin28-dependent pre-let-7 oligo-uridylylation.
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18
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Yashiro Y, Tomita K. Function and Regulation of Human Terminal Uridylyltransferases. Front Genet 2018; 9:538. [PMID: 30483311 PMCID: PMC6240794 DOI: 10.3389/fgene.2018.00538] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/24/2018] [Indexed: 11/21/2022] Open
Abstract
RNA uridylylation plays a pivotal role in the biogenesis and metabolism of functional RNAs, and regulates cellular gene expression. RNA uridylylation is catalyzed by a subset of proteins from the non-canonical terminal nucleotidyltransferase family. In human, three proteins (TUT1, TUT4, and TUT7) have been shown to exhibit template-independent uridylylation activity at 3′-end of specific RNAs. TUT1 catalyzes oligo-uridylylation of U6 small nuclear (sn) RNA, which catalyzes mRNA splicing. Oligo-uridylylation of U6 snRNA is required for U6 snRNA maturation, U4/U6-di-snRNP formation, and U6 snRNA recycling during mRNA splicing. TUT4 and TUT7 catalyze mono- or oligo-uridylylation of precursor let-7 (pre–let-7). Let-7 RNA is broadly expressed in somatic cells and regulates cellular proliferation and differentiation. Mono-uridylylation of pre–let-7 by TUT4/7 promotes subsequent Dicer processing to up-regulate let-7 biogenesis. Oligo-uridylylation of pre–let-7 by TUT4/7 is dependent on an RNA-binding protein, Lin28. Oligo-uridylylated pre–let-7 is less responsive to processing by Dicer and degraded by an exonuclease DIS3L2. As a result, let-7 expression is repressed. Uridylylation of pre–let-7 depends on the context of the 3′-region of pre–let-7 and cell type. In this review, we focus on the 3′ uridylylation of U6 snRNA and pre-let-7, and describe the current understanding of mechanism of activity and regulation of human TUT1 and TUT4/7, based on their crystal structures that have been recently solved.
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Affiliation(s)
- Yuka Yashiro
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Kozo Tomita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
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19
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Abstract
In bilaterian animals the 3′ ends of microRNAs (miRNAs) are frequently modified by tailing and trimming. These modifications affect miRNA-mediated gene regulation by modulating miRNA stability. Here, we analyzed data from three nonbilaterian animals: two cnidarians (Nematostella vectensis and Hydra magnipapillata) and one poriferan (Amphimedon queenslandica). Our analysis revealed that nonbilaterian miRNAs frequently undergo modifications like the bilaterian counterparts: the majority are expressed as different length isoforms and frequent modifications of the 3′ end by mono U or mono A tailing are observed. Moreover, as the factors regulating miRNA modifications are largely uncharacterized in nonbilaterian animal phyla, in present study, we investigated the evolution of 3′ terminal uridylyl transferases (TUTases) that are known to involved in miRNA 3′ nontemplated modifications in Bilateria. Phylogenetic analysis on TUTases showed that TUTase1 and TUTase6 are a result of duplication in bilaterians and that TUTase7 and TUTase4 are the result of a vertebrate-specific duplication. We also find an unexpected number of Drosophila-specific gene duplications and domain losses in most of the investigated gene families. Overall, our findings shed new light on the evolutionary history of TUTases in Metazoa, as they reveal that this core set of enzymes already existed in the last common ancestor of all animals and was probably involved in modifying small RNAs in a similar fashion to its present activity in bilaterians.
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Affiliation(s)
- Vengamanaidu Modepalli
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yehu Moran
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, Jerusalem, Israel
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20
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Kobyłecki K, Kuchta K, Dziembowski A, Ginalski K, Tomecki R. Biochemical and structural bioinformatics studies of fungal CutA nucleotidyltransferases explain their unusual specificity toward CTP and increased tendency for cytidine incorporation at the 3'-terminal positions of synthesized tails. RNA (NEW YORK, N.Y.) 2017; 23:1902-1926. [PMID: 28947555 PMCID: PMC5689010 DOI: 10.1261/rna.061010.117] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 09/12/2017] [Indexed: 05/25/2023]
Abstract
Noncanonical RNA nucleotidyltransferases (NTases), including poly(A), poly(U) polymerases (PAPs/PUPs), and C/U-adding enzymes, modify 3'-ends of different transcripts affecting their functionality and stability. They contain PAP/OAS1 substrate-binding domain (SBD) with inserted NTase domain. Aspergillus nidulans CutA (AnCutA), synthesizes C/U-rich 3'-terminal extensions in vivo. Here, using high-throughput sequencing of the 3'-RACE products for tails generated by CutA proteins in vitro in the presence of all four NTPs, we show that even upon physiological ATP excess synthesized tails indeed contain an unprecedented number of cytidines interrupted by uridines and stretches of adenosines, and that the majority end with two cytidines. Strikingly, processivity assays documented that in the presence of CTP as a sole nucleotide, the enzyme terminates after adding two cytidines only. Comparison of our CutA 3D model to selected noncanonical NTases of known structures revealed substantial differences in the nucleotide recognition motif (NRM) within PAP/OAS1 SBD. We demonstrate that CutA specificity toward CTP can be partially changed to PAP or PUP by rational mutagenesis within NRM and, analogously, Cid1 PUP can be converted into a C/U-adding enzyme. Collectively, we suggest that a short cluster of amino acids within NRM is a determinant of NTases' substrate preference, which may allow us to predict their specificity.
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Affiliation(s)
- Kamil Kobyłecki
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
- Department of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, 02-106 Warsaw, Poland
| | - Krzysztof Kuchta
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
| | - Andrzej Dziembowski
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
- Department of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, 02-106 Warsaw, Poland
| | - Krzysztof Ginalski
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, 02-089 Warsaw, Poland
| | - Rafał Tomecki
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
- Department of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, 02-106 Warsaw, Poland
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21
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De Almeida C, Scheer H, Zuber H, Gagliardi D. RNA uridylation: a key posttranscriptional modification shaping the coding and noncoding transcriptome. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 9. [PMID: 28984054 DOI: 10.1002/wrna.1440] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/03/2017] [Accepted: 08/07/2017] [Indexed: 12/27/2022]
Abstract
RNA uridylation is a potent and widespread posttranscriptional regulator of gene expression. RNA uridylation has been detected in a range of eukaryotes including trypanosomes, animals, plants, and fungi, but with the noticeable exception of budding yeast. Virtually all classes of eukaryotic RNAs can be uridylated and uridylation can also tag viral RNAs. The untemplated addition of a few uridines at the 3' end of a transcript can have a decisive impact on RNA's fate. In rare instances, uridylation is an intrinsic step in the maturation of noncoding RNAs like for the U6 spliceosomal RNA or mitochondrial guide RNAs in trypanosomes. Uridylation can also switch specific miRNA precursors from a degradative to a processing mode. This switch depends on the number of uridines added which is regulated by the cellular context. Yet, the typical consequence of uridylation on mature noncoding RNAs or their precursors is to accelerate decay. Importantly, mRNAs are also tagged by uridylation. In fact, the advent of novel high throughput sequencing protocols has recently revealed the pervasiveness of mRNA uridylation, from plants to humans. As for noncoding RNAs, the main function to date for mRNA uridylation is to promote degradation. Yet, additional roles begin to be ascribed to U-tailing such as the control of mRNA deadenylation, translation control and possibly storage. All these new findings illustrate that we are just beginning to appreciate the diversity of roles played by RNA uridylation and its full temporal and spatial implication in regulating gene expression. WIREs RNA 2018, 9:e1440. doi: 10.1002/wrna.1440 This article is categorized under: RNA Processing > 3' End Processing RNA Processing > RNA Editing and Modification RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms.
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Affiliation(s)
- Caroline De Almeida
- Institut de Biologie Moleculaire des Plantes (IBMP), CNRS, University of Strasbourg, Strasbourg, France
| | - Hélène Scheer
- Institut de Biologie Moleculaire des Plantes (IBMP), CNRS, University of Strasbourg, Strasbourg, France
| | - Hélène Zuber
- Institut de Biologie Moleculaire des Plantes (IBMP), CNRS, University of Strasbourg, Strasbourg, France
| | - Dominique Gagliardi
- Institut de Biologie Moleculaire des Plantes (IBMP), CNRS, University of Strasbourg, Strasbourg, France
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22
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Faehnle CR, Walleshauser J, Joshua-Tor L. Multi-domain utilization by TUT4 and TUT7 in control of let-7 biogenesis. Nat Struct Mol Biol 2017; 24:658-665. [PMID: 28671666 PMCID: PMC5542866 DOI: 10.1038/nsmb.3428] [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: 02/21/2017] [Accepted: 06/07/2017] [Indexed: 12/20/2022]
Abstract
The uridyl transferases TUT4 and TUT7 switch between two modes of activity that either promotes let-7 expression (monoU) or marks it for degradation (oligoU). Lin28 modulates the switch via recruitment of TUT4(7) to pre-let-7 in stem cells and human cancers. We found TUT4(7) utilize two multi-domain functional modules during the switch from mono- to oligoU. The catalytic module (CM) is essential for both activities, while the Lin28-interacting module (LIM) is indispensible for oligoU. The TUT7 CM structure trapped in the monoU state, revealed a duplex RNA binding pocket that orients group II pre-let-7 hairpins to position the 1-nt overhang favor monoU addition. Conversely, the switch to oligoU requires the ZK domain of Lin28 to drive the formation of a stable ternary complex between pre-let-7 and the inactive LIM. Finally, ZK2 of TUT4(7) aids oligoU addition by engaging the growing oligoU tail through uracil-specific interactions.
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Affiliation(s)
- Christopher R Faehnle
- W.M. Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA.,Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Jack Walleshauser
- W.M. Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA.,Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA.,Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Leemor Joshua-Tor
- W.M. Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA.,Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA.,Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
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23
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Yamashita S, Takagi Y, Nagaike T, Tomita K. Crystal structures of U6 snRNA-specific terminal uridylyltransferase. Nat Commun 2017; 8:15788. [PMID: 28589955 PMCID: PMC5467268 DOI: 10.1038/ncomms15788] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 04/27/2017] [Indexed: 02/06/2023] Open
Abstract
The terminal uridylyltransferase, TUT1, builds or repairs the 3′-oligo-uridylylated tail of U6 snRNA. The 3′-oligo-uridylylated tail is the Lsm-binding site for U4/U6 di-snRNP formation and U6 snRNA recycling for pre-mRNA splicing. Here, we report crystallographic and biochemical analyses of human TUT1, which revealed the mechanisms for the specific uridylylation of the 3′-end of U6 snRNA by TUT1. The O2 and O4 atoms of the UTP base form hydrogen bonds with the conserved His and Asn in the catalytic pocket, respectively, and TUT1 preferentially incorporates UMP onto the 3′-end of RNAs. TUT1 recognizes the entire U6 snRNA molecule by its catalytic domains, N-terminal RNA-recognition motifs and a previously unidentified C-terminal RNA-binding domain. Each domain recognizes specific regions within U6 snRNA, and the recognition is coupled with the domain movements and U6 snRNA structural changes. Hence, TUT1 functions as the U6 snRNA-specific terminal uridylyltransferase required for pre-mRNA splicing. After transcription the 3′-end of U6 snRNA is oligo-uridylylated by the terminal uridylyltransferase TUT1. Here the authors present the crystal structure of human TUT1 and give insights into the mechanism of 3′-end uridylylation by the enzyme.
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Affiliation(s)
- Seisuke Yamashita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Yuko Takagi
- National Institute of Advanced Industrial Science and Technology, Biomedical Research Institute, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan
| | - Takashi Nagaike
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Kozo Tomita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa, Chiba 277-8562, Japan
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24
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Aphasizhev R, Suematsu T, Zhang L, Aphasizheva I. Constructive edge of uridylation-induced RNA degradation. RNA Biol 2016; 13:1078-1083. [PMID: 27715485 PMCID: PMC5100348 DOI: 10.1080/15476286.2016.1229736] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 08/06/2016] [Accepted: 08/24/2016] [Indexed: 12/18/2022] Open
Abstract
RNA uridylation is a significant transcriptome-shaping factor in protists, fungi, metazoans, and plants. The 3' U-additions are catalyzed by terminal uridyltransferases (TUTases), a diverse group of enzymes that along with non-canonical poly(A) polymerases form a distinct group in the superfamily of DNA polymerase β-like nucleotidyl transferases. Within and across studied organisms and subcellular compartments, TUTases differ in nucleotide triphosphate selectivity, interacting partners, and RNA targets. A general premise linking RNA uridylation to 3'-5' degradation received support from several studies of small RNAs and mRNA turnover. However, recent work on kinetoplastid protists typified by Trypanosoma brucei provides evidence that RNA uridylation may play a more nuanced role in generating functional small RNAs. In this pathogen's mitochondrion, most mRNAs are internally edited by U-insertions and deletions, and subjected to 3' adenylation/uridylation; guide RNAs (gRNAs) required for editing are U-tailed. The prominent role of uridylation in mitochondrial RNA metabolism stimulated identification of the first TUTase, RNA editing TUTase 1 (RET1). Here we discuss functional studies of mitochondrial uridylation in trypanosomes that have revealed an unorthodox pathway of small RNA biogenesis. The current model accentuates physical coupling of RET1 and 3'-5' RNase II/RNB-type exonuclease DSS1 within a stable complex termed the mitochondrial 3' processome (MPsome). In the confines of this complex, RET1 initially uridylates a long precursor to activate its 3'-5' degradation by DSS1, and then uridylates trimmed guide RNA to disengage the processing complex from the mature molecule. We also discuss a potential role of antisense transcription in the MPsome pausing at a fixed distance from gRNA's 5' end. This step likely defines the mature 3' end by enabling kinetic competition between TUTase and exonuclease activities.
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Affiliation(s)
- Ruslan Aphasizhev
- Department of Molecular and Cell Biology, Boston University School of Dental Medicine, Boston, MA, USA
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, USA
| | - Takuma Suematsu
- Department of Molecular and Cell Biology, Boston University School of Dental Medicine, Boston, MA, USA
| | - Liye Zhang
- Section of Computational Biomedicine, Boston University School of Medicine, Boston, MA, USA
| | - Inna Aphasizheva
- Department of Molecular and Cell Biology, Boston University School of Dental Medicine, Boston, MA, USA
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25
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Rajappa-Titu L, Suematsu T, Munoz-Tello P, Long M, Demir Ö, Cheng KJ, Stagno JR, Luecke H, Amaro RE, Aphasizheva I, Aphasizhev R, Thore S. RNA Editing TUTase 1: structural foundation of substrate recognition, complex interactions and drug targeting. Nucleic Acids Res 2016; 44:10862-10878. [PMID: 27744351 PMCID: PMC5159558 DOI: 10.1093/nar/gkw917] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 09/27/2016] [Accepted: 10/04/2016] [Indexed: 11/13/2022] Open
Abstract
Terminal uridyltransferases (TUTases) execute 3′ RNA uridylation across protists, fungi, metazoan and plant species. Uridylation plays a particularly prominent role in RNA processing pathways of kinetoplastid protists typified by the causative agent of African sleeping sickness, Trypanosoma brucei. In mitochondria of this pathogen, most mRNAs are internally modified by U-insertion/deletion editing while guide RNAs and rRNAs are U-tailed. The founding member of TUTase family, RNA editing TUTase 1 (RET1), functions as a subunit of the 3′ processome in uridylation of gRNA precursors and mature guide RNAs. Along with KPAP1 poly(A) polymerase, RET1 also participates in mRNA translational activation. RET1 is divergent from human TUTases and is essential for parasite viability in the mammalian host and the insect vector. Given its robust in vitro activity, RET1 represents an attractive target for trypanocide development. Here, we report high-resolution crystal structures of the RET1 catalytic core alone and in complex with UTP analogs. These structures reveal a tight docking of the conserved nucleotidyl transferase bi-domain module with a RET1-specific C2H2 zinc finger and RNA recognition (RRM) domains. Furthermore, we define RET1 region required for incorporation into the 3′ processome, determinants for RNA binding, subunit oligomerization and processive UTP incorporation, and predict druggable pockets.
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Affiliation(s)
- Lional Rajappa-Titu
- Department of Molecular Biology, University of Geneva, 1211 Geneva, Switzerland
| | - Takuma Suematsu
- Department of Molecular and Cell Biology, Boston University School of Dental Medicine, Boston, MA 02118, USA
| | - Paola Munoz-Tello
- Department of Molecular Biology, University of Geneva, 1211 Geneva, Switzerland
| | - Marius Long
- Department of Molecular Biology, University of Geneva, 1211 Geneva, Switzerland
| | - Özlem Demir
- Department of Chemistry & Biochemistry and the National Biomedical Computation Resource, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kevin J Cheng
- Department of Chemistry & Biochemistry and the National Biomedical Computation Resource, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jason R Stagno
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA
| | - Hartmut Luecke
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA
| | - Rommie E Amaro
- Department of Chemistry & Biochemistry and the National Biomedical Computation Resource, University of California, San Diego, La Jolla, CA 92093, USA
| | - Inna Aphasizheva
- Department of Molecular and Cell Biology, Boston University School of Dental Medicine, Boston, MA 02118, USA
| | - Ruslan Aphasizhev
- Department of Molecular and Cell Biology, Boston University School of Dental Medicine, Boston, MA 02118, USA .,Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
| | - Stéphane Thore
- Department of Molecular Biology, University of Geneva, 1211 Geneva, Switzerland .,INSERM, U1212, ARNA Laboratory, Bordeaux 33000, France.,CNRS UMR5320, ARNA Laboratory, Bordeaux 33000, France.,University of Bordeaux, ARNA Laboratory, Bordeaux 33000, France
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26
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Scheer H, Zuber H, De Almeida C, Gagliardi D. Uridylation Earmarks mRNAs for Degradation… and More. Trends Genet 2016; 32:607-619. [PMID: 27592415 DOI: 10.1016/j.tig.2016.08.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/01/2016] [Accepted: 08/02/2016] [Indexed: 12/29/2022]
Abstract
Groundbreaking discoveries have uncovered the widespread post-transcriptional modifications of all classes of RNA. These studies have led to the emerging notion of an 'epitranscriptome' as a new layer of gene regulation. Diverse modifications control RNA fate, including the 3' addition of untemplated nucleotides or 3' tailing. The most exciting recent discoveries in 3' tailing are related to uridylation. Uridylation targets various noncoding RNAs, from small RNAs and their precursors to rRNAs, and U tails mostly regulate processing or degradation. Interestingly, uridylation is also a pervasive modification of mRNAs. In this review, we discuss how the addition of few uridines to the 3' end of mRNAs influences mRNA decay. We also consider recent findings that reveal other consequences of uridylation on mRNA fate.
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Affiliation(s)
- Hélène Scheer
- Institut de Biologie Moléculaire des Plantes (IBMP), Centre National de la Recherche Scientifique (CNRS), University of Strasbourg, 67000 Strasbourg, France
| | - Hélène Zuber
- Institut de Biologie Moléculaire des Plantes (IBMP), Centre National de la Recherche Scientifique (CNRS), University of Strasbourg, 67000 Strasbourg, France
| | - Caroline De Almeida
- Institut de Biologie Moléculaire des Plantes (IBMP), Centre National de la Recherche Scientifique (CNRS), University of Strasbourg, 67000 Strasbourg, France
| | - Dominique Gagliardi
- Institut de Biologie Moléculaire des Plantes (IBMP), Centre National de la Recherche Scientifique (CNRS), University of Strasbourg, 67000 Strasbourg, France.
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27
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Chung CZ, Jo DHS, Heinemann IU. Nucleotide specificity of the human terminal nucleotidyltransferase Gld2 (TUT2). RNA (NEW YORK, N.Y.) 2016; 22:1239-49. [PMID: 27284165 PMCID: PMC4931116 DOI: 10.1261/rna.056077.116] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 05/05/2016] [Indexed: 05/16/2023]
Abstract
The nontemplated addition of single or multiple nucleotides to RNA transcripts is an efficient means to control RNA stability and processing. Cytoplasmic RNA adenylation and the less well-known uridylation are post-transcriptional mechanisms regulating RNA maturation, activity, and degradation. Gld2 is a member of the noncanonical poly(A) polymerases, which include enzymes with varying nucleotide specificity, ranging from strictly ATP to ambiguous to exclusive UTP adding enzymes. Human Gld2 has been associated with transcript stabilizing miRNA monoadenylation and cytoplasmic mRNA polyadenylation. Most recent data have uncovered an unexpected miRNA uridylation activity, which promotes miRNA maturation. These conflicting data raise the question of Gld2 nucleotide specificity. Here, we biochemically characterized human Gld2 and demonstrated that it is a bona fide adenylyltransferase with only weak activity toward other nucleotides. Despite its sequence similarity with uridylyltransferases (TUT4, TUT7), Gld2 displays an 83-fold preference of ATP over UTP. Gld2 is a promiscuous enzyme, with activity toward miRNA, pre-miRNA, and polyadenylated RNA substrates. Apo-Gld2 activity is restricted to adding single nucleotides and processivity likely relies on additional RNA-binding proteins. A phylogeny of the PAP/TUTase superfamily suggests that uridylyltransferases, which are derived from distinct adenylyltransferase ancestors, arose multiple times during evolution via insertion of an active site histidine. A corresponding histidine insertion into the Gld2 active site alters substrate specificity from ATP to UTP.
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Affiliation(s)
- Christina Z Chung
- Department of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - David Hyung Suk Jo
- Department of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Ilka U Heinemann
- Department of Biochemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
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28
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MicroRNA-mediated target mRNA cleavage and 3'-uridylation in human cells. Sci Rep 2016; 6:30242. [PMID: 27440378 PMCID: PMC4954961 DOI: 10.1038/srep30242] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 06/08/2016] [Indexed: 12/17/2022] Open
Abstract
MicroRNAs (miRNAs) play an important role in targeted gene silencing by facilitating posttranscriptional and translational repression. However, the precise mechanism of mammalian miRNA-mediated gene silencing remains to be elucidated. Here, we used a stem-loop array reverse-transcription polymerase chain reaction assay to analyse miRNA-induced mRNA recognition, cleavage, posttranscriptional modification, and degradation. We detected endogenous let-7 miRNA-induced and Argonaute-catalysed endonucleolytic cleavage on target mRNAs at various sites within partially paired miRNA:mRNA sequences. Most of the cleaved mRNA 5′-fragments were 3′-oligouridylated by activities of terminal uridylyl transferases (TUTases) in miRNA-induced silencing complexes and temporarily accumulated in the cytosol for 5′-3′ degradation or other molecular fates. Some 3′-5′ decayed mRNA fragments could also be captured by the miRNA-induced silencing complex stationed at the specific miRNA:mRNA target site and oligouridylated by other TUTases at its proximity without involving Argonaute-mediated RNA cleavage. Our findings provide new insights into the molecular mechanics of mammalian miRNA-mediated gene silencing by coordinated target mRNA recognition, cleavage, uridylation and degradation.
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29
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Abstract
The RNA-binding protein Lin28 regulates the expression of the let-7 family of microRNAs (miRNAs) during early embryonic development. Lin28 recruits the 3' terminal uridylyl transferase (TUTase) Zcchc11 (TUT4) and/or Zcchc6 (TUT7) to precursor let-7 RNA (pre-let-7) to selectively block let-7 biogenesis. Uridylated pre-let-7 is targeted for decay by the downstream exonuclease Dis3l2 thereby preventing processing to mature let-7. Activation of this oncogenic pathway via up-regulation of Lin28 expression promotes cellular transformation, drives tumorigenesis in mouse models, and is frequently observed in a wide variety of cancer. Recent proof-of-principle experiments showed that Zcchc11 knockdown inhibits the tumorigenicity of Lin28-expressing human cancer cells and established this enzyme as a possible new therapeutic target for human malignancies. However, there are currently no known pharmacological agents capable of targeting this novel enzyme. In this study we developed and applied a sensitive biochemical assay that monitors Zcchc11 activity. Using this assay we performed an automated high-throughput screen of ∼ 15,000 chemicals to identify putative TUTase inhibitors. Several of these small molecules were validated as specific inhibitors of Zcchc11 activity. Our results demonstrate the feasibility of screening for TUTase inhibitors and present a relatively simple platform that can be exploited for future drug discovery efforts aimed at restoring let-7 expression in cancer.
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Affiliation(s)
- Shuibin Lin
- a Stem Cell Program ; Boston Children's Hospital ; Boston , MA USA
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30
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Cording A, Gormally M, Bond PJ, Carrington M, Balasubramanian S, Miska EA, Thomas B. Selective inhibitors of trypanosomal uridylyl transferase RET1 establish druggability of RNA post-transcriptional modifications. RNA Biol 2016; 14:611-619. [PMID: 26786754 PMCID: PMC5449093 DOI: 10.1080/15476286.2015.1137422] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Non-coding RNAs are crucial regulators for a vast array of cellular processes and have been implicated in human disease. These biological processes represent a hitherto untapped resource in our fight against disease. In this work we identify small molecule inhibitors of a non-coding RNA uridylylation pathway. The TUTase family of enzymes is important for modulating non-coding RNA pathways in both human cancer and pathogen systems. We demonstrate that this new class of drug target can be accessed with traditional drug discovery techniques. Using the Trypanosoma brucei TUTase, RET1, we identify TUTase inhibitors and lay the groundwork for the use of this new target class as a therapeutic opportunity for the under-served disease area of African Trypanosomiasis. In a broader sense this work demonstrates the therapeutic potential for targeting RNA post-transcriptional modifications with small molecules in human disease.
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Affiliation(s)
- Amy Cording
- a The Gurdon Institute, University of Cambridge , Cambridge , UK
| | - Michael Gormally
- b Department of Chemistry , University of Cambridge , Cambridge , UK.,c Cancer Research UK Cambridge Institute, Li Ka Shing Center , Cambridge , UK.,d National Center for Advancing Translational Sciences , National Institutes of Health , Bethesda , MD , USA
| | - Peter J Bond
- e Bioinformatics Institute (A*STAR) , Singapore.,f Department of Biological Sciences , National University of Singapore , Singapore
| | | | - Shankar Balasubramanian
- b Department of Chemistry , University of Cambridge , Cambridge , UK.,c Cancer Research UK Cambridge Institute, Li Ka Shing Center , Cambridge , UK
| | - Eric A Miska
- a The Gurdon Institute, University of Cambridge , Cambridge , UK
| | - Beth Thomas
- b Department of Chemistry , University of Cambridge , Cambridge , UK
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31
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Lapkouski M, Hällberg BM. Structure of mitochondrial poly(A) RNA polymerase reveals the structural basis for dimerization, ATP selectivity and the SPAX4 disease phenotype. Nucleic Acids Res 2015; 43:9065-75. [PMID: 26319014 PMCID: PMC4605311 DOI: 10.1093/nar/gkv861] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/14/2015] [Indexed: 01/23/2023] Open
Abstract
Polyadenylation, performed by poly(A) polymerases (PAPs), is a ubiquitous post-transcriptional modification that plays key roles in multiple aspects of RNA metabolism. Although cytoplasmic and nuclear PAPs have been studied extensively, the mechanism by which mitochondrial PAP (mtPAP) selects adenosine triphosphate over other nucleotides is unknown. Furthermore, mtPAP is unique because it acts as a dimer. However, mtPAP's dimerization requirement remains enigmatic. Here, we show the structural basis for mtPAP's nucleotide selectivity, dimerization and catalysis. Our structures reveal an intricate dimerization interface that features an RNA-recognition module formed through strand complementation. Further, we propose the structural basis for the N478D mutation that drastically reduces the length of poly(A) tails on mitochondrial mRNAs in patients with spastic ataxia 4 (SPAX4), a severe and progressive neurodegenerative disease.
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Affiliation(s)
- Mikalai Lapkouski
- Department of Cell and Molecular Biology, Karolinska Institutet, 171 77 Stockholm, Sweden Röntgen-Ångström-Cluster, Karolinska Institutet Outstation, Centre for Structural Systems Biology, DESY-Campus, 22607 Hamburg, Germany
| | - B Martin Hällberg
- Department of Cell and Molecular Biology, Karolinska Institutet, 171 77 Stockholm, Sweden Röntgen-Ångström-Cluster, Karolinska Institutet Outstation, Centre for Structural Systems Biology, DESY-Campus, 22607 Hamburg, Germany European Molecular Biology Laboratory, Hamburg Unit, 22607 Hamburg, Germany
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32
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Structural basis for the activation of the C. elegans noncanonical cytoplasmic poly(A)-polymerase GLD-2 by GLD-3. Proc Natl Acad Sci U S A 2015; 112:8614-9. [PMID: 26124149 DOI: 10.1073/pnas.1504648112] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Caenorhabditis elegans germ-line development defective (GLD)-2-GLD-3 complex up-regulates the expression of genes required for meiotic progression. GLD-2-GLD-3 acts by extending the short poly(A) tail of germ-line-specific mRNAs, switching them from a dormant state into a translationally active state. GLD-2 is a cytoplasmic noncanonical poly(A) polymerase that lacks the RNA-binding domain typical of the canonical nuclear poly(A)-polymerase Pap1. The activity of C. elegans GLD-2 in vivo and in vitro depends on its association with the multi-K homology (KH) domain-containing protein, GLD-3, a homolog of Bicaudal-C. We have identified a minimal polyadenylation complex that includes the conserved nucleotidyl-transferase core of GLD-2 and the N-terminal domain of GLD-3, and determined its structure at 2.3-Å resolution. The structure shows that the N-terminal domain of GLD-3 does not fold into the predicted KH domain but wraps around the catalytic domain of GLD-2. The picture that emerges from the structural and biochemical data are that GLD-3 activates GLD-2 both indirectly by stabilizing the enzyme and directly by contributing positively charged residues near the RNA-binding cleft. The RNA-binding cleft of GLD-2 has distinct structural features compared with the poly(A)-polymerases Pap1 and Trf4. Consistently, GLD-2 has distinct biochemical properties: It displays unusual specificity in vitro for single-stranded RNAs with at least one adenosine at the 3' end. GLD-2 thus appears to have evolved specialized nucleotidyl-transferase properties that match the 3' end features of dormant cytoplasmic mRNAs.
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33
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Kim B, Ha M, Loeff L, Chang H, Simanshu DK, Li S, Fareh M, Patel DJ, Joo C, Kim VN. TUT7 controls the fate of precursor microRNAs by using three different uridylation mechanisms. EMBO J 2015; 34:1801-15. [PMID: 25979828 PMCID: PMC4516432 DOI: 10.15252/embj.201590931] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 04/08/2015] [Indexed: 01/04/2023] Open
Abstract
Terminal uridylyl transferases (TUTs) function as integral regulators of microRNA (miRNA) biogenesis. Using biochemistry, single-molecule, and deep sequencing techniques, we here investigate the mechanism by which human TUT7 (also known as ZCCHC6) recognizes and uridylates precursor miRNAs (pre-miRNAs) in the absence of Lin28. We find that the overhang of a pre-miRNA is the key structural element that is recognized by TUT7 and its paralogues, TUT4 (ZCCHC11) and TUT2 (GLD2/PAPD4). For group II pre-miRNAs, which have a 1-nt 3′ overhang, TUT7 restores the canonical end structure (2-nt 3′ overhang) through mono-uridylation, thereby promoting miRNA biogenesis. For pre-miRNAs where the 3′ end is further recessed into the stem (as in 3′ trimmed pre-miRNAs), TUT7 generates an oligo-U tail that leads to degradation. In contrast to Lin28-stimulated oligo-uridylation, which is processive, a distributive mode is employed by TUT7 for both mono- and oligo-uridylation in the absence of Lin28. The overhang length dictates the frequency (but not duration) of the TUT7-RNA interaction, thus explaining how TUT7 differentiates pre-miRNA species with different overhangs. Our study reveals dual roles and mechanisms of uridylation in repair and removal of defective pre-miRNAs.
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Affiliation(s)
- Boseon Kim
- Center for RNA Research, Institute for Basic Science, Seoul, Korea School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Minju Ha
- Center for RNA Research, Institute for Basic Science, Seoul, Korea School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Luuk Loeff
- Kavli Institute of NanoScience, Department of BioNanoScience, Delft University of Technology, Delft, The Netherlands
| | - Hyeshik Chang
- Center for RNA Research, Institute for Basic Science, Seoul, Korea School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Dhirendra K Simanshu
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - Sisi Li
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - Mohamed Fareh
- Kavli Institute of NanoScience, Department of BioNanoScience, Delft University of Technology, Delft, The Netherlands
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - Chirlmin Joo
- Kavli Institute of NanoScience, Department of BioNanoScience, Delft University of Technology, Delft, The Netherlands
| | - V Narry Kim
- Center for RNA Research, Institute for Basic Science, Seoul, Korea School of Biological Sciences, Seoul National University, Seoul, Korea
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34
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Yates LA, Durrant BP, Barber M, Harlos K, Fleurdépine S, Norbury CJ, Gilbert RJC. Improved crystallization and diffraction of caffeine-induced death suppressor protein 1 (Cid1). ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS 2015; 71:346-53. [PMID: 25760713 PMCID: PMC4356314 DOI: 10.1107/s2053230x15001351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 01/21/2015] [Indexed: 11/25/2022]
Abstract
The use of truncation and RNA-binding mutations of caffeine induced death suppressor protein 1 (Cid1) as a means to enhance crystallogenesis leading to an improvement of X-ray diffraction resolution by 1.5 Å is reported. The post-transcriptional addition of uridines to the 3′-end of RNAs is an important regulatory process that is critical for coding and noncoding RNA stability. In fission yeast and metazoans this untemplated 3′-uridylylation is catalysed by a single family of terminal uridylyltransferases (TUTs) whose members are adapted to specific RNA targets. In Schizosaccharomyces pombe the TUT Cid1 is responsible for the uridylylation of polyadenylated mRNAs, targeting them for destruction. In metazoans, the Cid1 orthologues ZCCHC6 and ZCCHC11 uridylate histone mRNAs, targeting them for degradation, but also uridylate microRNAs, altering their maturation. Cid1 has been studied as a model TUT that has provided insights into the larger and more complex metazoan enzyme system. In this paper, two strategies are described that led to improvements both in the crystallogenesis of Cid1 and in the resolution of diffraction by ∼1.5 Å. These advances have allowed high-resolution crystallographic studies of this TUT system to be initiated.
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Affiliation(s)
- Luke A Yates
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, England
| | - Benjamin P Durrant
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, England
| | - Michael Barber
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, England
| | - Karl Harlos
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, England
| | - Sophie Fleurdépine
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, England
| | - Chris J Norbury
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, England
| | - Robert J C Gilbert
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, England
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35
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Yates LA, Durrant BP, Fleurdépine S, Harlos K, Norbury CJ, Gilbert RJC. Structural plasticity of Cid1 provides a basis for its distributive RNA terminal uridylyl transferase activity. Nucleic Acids Res 2015; 43:2968-79. [PMID: 25712096 PMCID: PMC4357723 DOI: 10.1093/nar/gkv122] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Terminal uridylyl transferases (TUTs) are responsible for the post-transcriptional addition of uridyl residues to RNA 3′ ends, leading in some cases to altered stability. The Schizosaccharomyces pombe TUT Cid1 is a model enzyme that has been characterized structurally at moderate resolution and provides insights into the larger and more complex mammalian TUTs, ZCCHC6 and ZCCHC11. Here, we report a higher resolution (1.74 Å) crystal structure of Cid1 that provides detailed evidence for uracil selection via the dynamic flipping of a single histidine residue. We also describe a novel closed conformation of the enzyme that may represent an intermediate stage in a proposed product ejection mechanism. The structural insights gained, combined with normal mode analysis and biochemical studies, demonstrate that the plasticity of Cid1, particularly about a hinge region (N164–N165), is essential for catalytic activity, and provide an explanation for its distributive uridylyl transferase activity. We propose a model clarifying observed differences between the in vitro apparently processive activity and in vivo distributive monouridylylation activity of Cid1. We suggest that modulating the flexibility of such enzymes—for example by the binding of protein co-factors—may allow them alternatively to add single or multiple uridyl residues to the 3′ termini of RNA molecules.
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Affiliation(s)
- Luke A Yates
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Benjamin P Durrant
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Sophie Fleurdépine
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Karl Harlos
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Chris J Norbury
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Robert J C Gilbert
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
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Yoon JY, Lee SJ, Kim DJ, Lee BJ, Yang JK, Suh SW. Crystal structure of JHP933 fromHelicobacter pyloriJ99 shows two-domain architecture with a DUF1814 family nucleotidyltransferase domain and a helical bundle domain. Proteins 2014; 82:2275-81. [DOI: 10.1002/prot.24572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 03/03/2014] [Accepted: 03/21/2014] [Indexed: 01/26/2023]
Affiliation(s)
- Ji Young Yoon
- Department of Chemistry; College of Natural Sciences, Seoul National University; Seoul 151-742 Republic of Korea
| | - Sang Jae Lee
- The Research Institute of Pharmaceutical Sciences; College of Pharmacy, Seoul National University, Gwanak-gu; Seoul 151-742 Republic of Korea
| | - Do Jin Kim
- Department of Chemistry; College of Natural Sciences, Seoul National University; Seoul 151-742 Republic of Korea
| | - Bong-Jin Lee
- The Research Institute of Pharmaceutical Sciences; College of Pharmacy, Seoul National University, Gwanak-gu; Seoul 151-742 Republic of Korea
| | - Jin Kuk Yang
- Department of Chemistry; College of Natural Sciences, Soongsil University; Seoul 156-743 Republic of Korea
| | - Se Won Suh
- Department of Chemistry; College of Natural Sciences, Seoul National University; Seoul 151-742 Republic of Korea
- Department of Biophysics and Chemical Biology; College of Natural Sciences, Seoul National University; Seoul 151-742 Republic of Korea
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37
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Yates LA, Gilbert RJC. Efficient production and purification of recombinant murine kindlin-3 from insect cells for biophysical studies. J Vis Exp 2014. [PMID: 24686835 PMCID: PMC4153465 DOI: 10.3791/51206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Kindlins are essential coactivators, with talin, of the cell surface receptors integrins and also participate in integrin outside-in signalling, and the control of gene transcription in the cell nucleus. The kindlins are ~75 kDa multidomain proteins and bind to an NPxY motif and upstream T/S cluster of the integrin β-subunit cytoplasmic tail. The hematopoietically-important kindlin isoform, kindlin-3, is critical for platelet aggregation during thrombus formation, leukocyte rolling in response to infection and inflammation and osteoclast podocyte formation in bone resorption. Kindlin-3's role in these processes has resulted in extensive cellular and physiological studies. However, there is a need for an efficient method of acquiring high quality milligram quantities of the protein for further studies. We have developed a protocol, here described, for the efficient expression and purification of recombinant murine kindlin-3 by use of a baculovirus-driven expression system in Sf9 cells yielding sufficient amounts of high purity full-length protein to allow its biophysical characterization. The same approach could be taken in the study of the other mammalian kindlin isoforms.
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Affiliation(s)
- Luke A Yates
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford;
| | - Robert J C Gilbert
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford;
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38
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Munoz-Tello P, Gabus C, Thore S. A critical switch in the enzymatic properties of the Cid1 protein deciphered from its product-bound crystal structure. Nucleic Acids Res 2013; 42:3372-80. [PMID: 24322298 PMCID: PMC3950679 DOI: 10.1093/nar/gkt1278] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The addition of uridine nucleotide by the poly(U) polymerase (PUP) enzymes has a demonstrated impact on various classes of RNAs such as microRNAs (miRNAs), histone-encoding RNAs and messenger RNAs. Cid1 protein is a member of the PUP family. We solved the crystal structure of Cid1 in complex with non-hydrolyzable UMPNPP and a short dinucleotide compound ApU. These structures revealed new residues involved in substrate/product stabilization. In particular, one of the three catalytic aspartate residues explains the RNA dependence of its PUP activity. Moreover, other residues such as residue N165 or the β-trapdoor are shown to be critical for Cid1 activity. We finally suggest that the length and sequence of Cid1 substrate RNA influence the balance between Cid1's processive and distributive activities. We propose that particular processes regulated by PUPs require the enzymes to switch between the two types of activity as shown for the miRNA biogenesis where PUPs can either promote DICER cleavage via short U-tail or trigger miRNA degradation by adding longer poly(U) tail. The enzymatic properties of these enzymes may be critical for determining their particular function in vivo.
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Affiliation(s)
- Paola Munoz-Tello
- Department of Molecular Biology, University of Geneva, Geneva, 1211, Switzerland
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39
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Abstract
The addition of poly(A) tails to eukaryotic nuclear mRNAs promotes their stability, export to the cytoplasm and translation. Subsequently, the balance between exonucleolytic deadenylation and selective re-establishment of translation-competent poly(A) tails by cytoplasmic poly(A) polymerases is essential for the appropriate regulation of gene expression from oocytes to neurons. In recent years, surprising roles for cytoplasmic poly(A) polymerase-related enzymes that add uridylyl, rather than adenylyl, residues to RNA 3' ends have also emerged. These terminal uridylyl transferases promote the turnover of certain mRNAs but also modify microRNAs, their precursors and other small RNAs to modulate their stability or biological functions.
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Affiliation(s)
- Chris J Norbury
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
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40
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Yates LA, Norbury CJ, Gilbert RJC. The long and short of microRNA. Cell 2013; 153:516-9. [PMID: 23622238 DOI: 10.1016/j.cell.2013.04.003] [Citation(s) in RCA: 543] [Impact Index Per Article: 49.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 02/20/2013] [Accepted: 03/08/2013] [Indexed: 12/17/2022]
Abstract
MicroRNAs (miRNAs) are versatile regulators of gene expression in higher eukaryotes. In order to silence many different mRNAs in a precise manner, miRNA stability and efficacy is controlled by highly developed regulatory pathways and fine-tuning mechanisms both affecting miRNA processing and altering mature miRNA target specificity.
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Affiliation(s)
- Luke A Yates
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
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41
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Sement FM, Ferrier E, Zuber H, Merret R, Alioua M, Deragon JM, Bousquet-Antonelli C, Lange H, Gagliardi D. Uridylation prevents 3' trimming of oligoadenylated mRNAs. Nucleic Acids Res 2013; 41:7115-27. [PMID: 23748567 PMCID: PMC3737552 DOI: 10.1093/nar/gkt465] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Degradation of mRNAs is usually initiated by deadenylation, the shortening of long poly(A) tails to oligo(A) tails of 12–15 As. Deadenylation leads to decapping and to subsequent 5′ to 3′ degradation by XRN proteins, or alternatively 3′ to 5′ degradation by the exosome. Decapping can also be induced by uridylation as shown for the non-polyadenylated histone mRNAs in humans and for several mRNAs in Schizosaccharomyces pombe and Aspergillus nidulans. Here we report a novel role for uridylation in preventing 3′ trimming of oligoadenylated mRNAs in Arabidopsis. We show that oligo(A)-tailed mRNAs are uridylated by the cytosolic UTP:RNA uridylyltransferase URT1 and that URT1 has no major impact on mRNA degradation rates. However, in absence of uridylation, oligo(A) tails are trimmed, indicating that uridylation protects oligoadenylated mRNAs from 3′ ribonucleolytic attacks. This conclusion is further supported by an increase in 3′ truncated transcripts detected in urt1 mutants. We propose that preventing 3′ trimming of oligo(A)-tailed mRNAs by uridylation participates in establishing the 5′ to 3′ directionality of mRNA degradation. Importantly, uridylation prevents 3′ shortening of mRNAs associated with polysomes, suggesting that a key biological function of uridylation is to confer 5′ to 3′ polarity in case of co-translational mRNA decay.
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Affiliation(s)
- François Michaël Sement
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg, 12 rue du général Zimmer, 67084 Strasbourg Cedex, France
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42
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Lapointe CP, Wickens M. The nucleic acid-binding domain and translational repression activity of a Xenopus terminal uridylyl transferase. J Biol Chem 2013; 288:20723-33. [PMID: 23709223 DOI: 10.1074/jbc.m113.455451] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Terminal uridylyl transferases (TUTs) catalyze the addition of uridines to the 3' ends of RNAs and are implicated in the regulation of both messenger RNAs and microRNAs. To better understand how TUTs add uridines to RNAs, we focused on a putative TUT from Xenopus laevis, XTUT7. We determined that XTUT7 catalyzed the addition of uridines to RNAs. Mutational analysis revealed that a truncated XTUT7 enzyme, which contained solely the nucleotidyl transferase and poly(A) polymerase-associated domains, was sufficient for catalytic activity. XTUT7 activity decreased upon removal of the CCHC zinc finger domains and a short segment of basic amino acids (the basic region). This basic region bound nucleic acids in vitro. We also demonstrated that XTUT7 repressed translation of a polyadenylated RNA, to which it added a distinct number of uridines. We generated a predicted structure of the XTUT7 catalytic core that indicated histidine 1269 was likely important for uridine specificity. Indeed, mutation of histidine 1269 broadened the nucleotide specificity of XTUT7 and abolished XTUT7-dependent translational repression. Our data reveal key aspects of how XTUT7 adds uridines to RNAs, highlight the role of the basic region, illustrate that XTUT7 can repress translation, and identify an amino acid important for uridine specificity.
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Affiliation(s)
- Christopher P Lapointe
- Integrated Program in Biochemistry, University of Wisconsin, Madison, Wisconsin 53706, USA
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Denti MA, Viero G, Provenzani A, Quattrone A, Macchi P. mRNA fate: Life and death of the mRNA in the cytoplasm. RNA Biol 2013; 10:360-6. [PMID: 23466755 DOI: 10.4161/rna.23770] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The life of an mRNA molecule begins with transcription and ultimately ends in degradation. In the course of its life, however, mRNA is examined, modified in various ways and transported before eventually being translated into proteins. All these processes are performed by proteins and non-coding RNAs whose complex interplay in the cell contributes to determining the proteome changes and the phenotype of cells. On May 23‒26, 2012, over 150 scientists from around the world convened in the sunny shores of Riva del Garda, Italy, for the workshop entitled: "mRNA fate: Life and Death of mRNA in the Cytoplasm." Sessions included mRNA trafficking, mRNA translational control, RNA metabolism and disease, RNA-protein structures and systems biology of RNA. This report highlights some of the prominent and recurring themes at the meeting and emerging arenas of future research.
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Scott DD, Norbury CJ. RNA decay via 3' uridylation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2013; 1829:654-65. [PMID: 23385389 DOI: 10.1016/j.bbagrm.2013.01.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2012] [Revised: 01/22/2013] [Accepted: 01/24/2013] [Indexed: 11/30/2022]
Abstract
The post-transcriptional addition of non-templated nucleotides to the 3' ends of RNA molecules can have a profound impact on their stability and biological function. Evidence accumulated over the past few decades has identified roles for polyadenylation in RNA stabilisation, degradation and, in the case of eukaryotic mRNAs, translational competence. By contrast, the biological significance of RNA 3' modification by uridylation has only recently started to become apparent. The evolutionary origin of eukaryotic RNA terminal uridyltransferases can be traced to an ancestral poly(A) polymerase. Here we review what is currently known about the biological roles of these enzymes, the ways in which their activity is regulated and the consequences of this covalent modification for the target RNA molecule, with a focus on those instances where uridylation has been found to contribute to RNA degradation. Roles for uridylation have been identified in the turnover of mRNAs, pre-microRNAs, piwi-interacting RNAs and the products of microRNA-directed mRNA cleavage; many mature microRNAs are also modified by uridylation, though the consequences in this case are currently less well understood. In the case of piwi-interacting RNAs, modification of the 3'-terminal nucleotide by the HEN1 methyltransferase blocks uridylation and so stabilises the small RNA. The extent to which other uridylation-dependent mechanisms of RNA decay are similarly regulated awaits further investigation. This article is part of a Special Issue entitled: RNA Decay mechanisms.
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Affiliation(s)
- Daniel D Scott
- University of Oxford, Sir William Dunn School of Pathology, Oxford, UK.
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