1
|
Dutta DJ, Sasaki J, Bansal A, Sugai K, Yamashita S, Li G, Lazarski C, Wang L, Sasaki T, Yamashita C, Carryl H, Suzuki R, Odawara M, Imamura Kawasawa Y, Rakic P, Torii M, Hashimoto-Torii K. Alternative splicing events as peripheral biomarkers for motor learning deficit caused by adverse prenatal environments. Proc Natl Acad Sci U S A 2023; 120:e2304074120. [PMID: 38051767 PMCID: PMC10723155 DOI: 10.1073/pnas.2304074120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 10/25/2023] [Indexed: 12/07/2023] Open
Abstract
Severity of neurobehavioral deficits in children born from adverse pregnancies, such as maternal alcohol consumption and diabetes, does not always correlate with the adversity's duration and intensity. Therefore, biological signatures for accurate prediction of the severity of neurobehavioral deficits, and robust tools for reliable identification of such biomarkers, have an urgent clinical need. Here, we demonstrate that significant changes in the alternative splicing (AS) pattern of offspring lymphocyte RNA can function as accurate peripheral biomarkers for motor learning deficits in mouse models of prenatal alcohol exposure (PAE) and offspring of mother with diabetes (OMD). An aptly trained deep-learning model identified 29 AS events common to PAE and OMD as superior predictors of motor learning deficits than AS events specific to PAE or OMD. Shapley-value analysis, a game-theory algorithm, deciphered the trained deep-learning model's learnt associations between its input, AS events, and output, motor learning performance. Shapley values of the deep-learning model's input identified the relative contribution of the 29 common AS events to the motor learning deficit. Gene ontology and predictive structure-function analyses, using Alphafold2 algorithm, supported existing evidence on the critical roles of these molecules in early brain development and function. The direction of most AS events was opposite in PAE and OMD, potentially from differential expression of RNA binding proteins in PAE and OMD. Altogether, this study posits that AS of lymphocyte RNA is a rich resource, and deep-learning is an effective tool, for discovery of peripheral biomarkers of neurobehavioral deficits in children of diverse adverse pregnancies.
Collapse
Affiliation(s)
- Dipankar J. Dutta
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
| | - Junko Sasaki
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
- Department of Diabetes, Endocrinology and Metabolism, Tokyo Medical University, Tokyo160-8402, Japan
| | - Ankush Bansal
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
| | - Keiji Sugai
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
- Department of Diabetes, Endocrinology and Metabolism, Tokyo Medical University, Tokyo160-8402, Japan
| | - Satoshi Yamashita
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
| | - Guojiao Li
- Department of Diabetes, Endocrinology and Metabolism, Tokyo Medical University, Tokyo160-8402, Japan
| | - Christopher Lazarski
- Center for Cancer and Immunology Research, Children’s National Hospital, Washington, DC20010
| | - Li Wang
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
| | - Toru Sasaki
- Department of Obstetrics and Gynecology, Tokyo Medical University, Tokyo160-8402, Japan
| | - Chiho Yamashita
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
| | - Heather Carryl
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
| | - Ryo Suzuki
- Department of Diabetes, Endocrinology and Metabolism, Tokyo Medical University, Tokyo160-8402, Japan
| | - Masato Odawara
- Department of Diabetes, Endocrinology and Metabolism, Tokyo Medical University, Tokyo160-8402, Japan
| | - Yuka Imamura Kawasawa
- Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, PA17033
| | - Pasko Rakic
- Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT06520
| | - Masaaki Torii
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
- Department of Pediatrics, Pharmacology and Physiology, George Washington University, Washington, DC20010
| | - Kazue Hashimoto-Torii
- Center for Neuroscience Research, Children’s National Hospital,Washington, DC20010
- Department of Pediatrics, Pharmacology and Physiology, George Washington University, Washington, DC20010
| |
Collapse
|
2
|
Stein RL, Wilson DM. Kinetic and Mechanistic Studies of the Terminal Uridylyltransferase, Zcchc11 (TUT4). Biochemistry 2022; 61:1614-1624. [PMID: 35797480 DOI: 10.1021/acs.biochem.2c00146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Zcchc11 (TUT4, TENT3A, Z11) is a nucleotidyltransferase that catalyzes the 3'-polyuridylation of RNA. Our interest in this enzyme stems from its role in blocking the biogenesis of let-7, a family of microRNAs whose members act as tumor suppressors. Z11 polyuridylates pre-let-7, the precursor of let-7, when pre-let-7 is complexed with LIN28, an RNA-binding protein. Polyuridylation of pre-let-7 marks it for degradation. In addition to this LIN28-dependent activity, Z11 also has LIN28-independent activities. In this paper, we report the results of experiments that characterize LIN28-independent activities of Z11. Significant observations include the following. (1) Z11 uridylates not only mature let-7 species but also substrates as small as dinucleotides. (2) For both let-7i and the diribonucleotide AG, Z11 follows a steady-state ordered mechanism, with UTP adding before RNA. (3) Uridylation kinetics of let-7i (UGAGGUAGUAGUUUGUGCUGUU) and two truncated derivatives, GCUGUU and UU, indicate that Z11 manifests selectivity in Km,RNA; kcat,RNA values for the three substrates are nearly identical. (4) Z11 preferentially uridylates RNA lacking base-pairing near the 3' terminus. (5) Selectivity of Z11 toward ribonucleoside triphosphates is similar for let-7i and AG, with XTP preference: UTP > CTP > ATP ≫ GTP. Selectivity is manifested in Km,XTP, with kcat,XTP values being similar for UTP, CTP, and ATP. (6) Kinetic parameters for RNA turnover are dependent on the structure of the nucleoside triphosphate, consistent with recent structural data indicating stacking of the nucleoside triphosphate base with the base of the 3'-nucleotide of the substrate RNA (Faehnle et al., Nat. Struct. Mol. Biol. 2017, 24, 658).
Collapse
Affiliation(s)
- Ross L Stein
- Twentyeight-Seven Therapeutics, 490 Arsenal Way, Watertown, Massachusetts 02472, United States
| | - David M Wilson
- Twentyeight-Seven Therapeutics, 490 Arsenal Way, Watertown, Massachusetts 02472, United States
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
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: 47] [Impact Index Per Article: 11.8] [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.
Collapse
|
5
|
Toompuu M, Tuomela T, Laine P, Paulin L, Dufour E, Jacobs HT. Polyadenylation and degradation of structurally abnormal mitochondrial tRNAs in human cells. Nucleic Acids Res 2019. [PMID: 29518244 PMCID: PMC6007314 DOI: 10.1093/nar/gky159] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
RNA 3' polyadenylation is known to serve diverse purposes in biology, in particular, regulating mRNA stability and translation. Here we determined that, upon exposure to high levels of the intercalating agent ethidium bromide (EtBr), greater than those required to suppress mitochondrial transcription, mitochondrial tRNAs in human cells became polyadenylated. Relaxation of the inducing stress led to rapid turnover of the polyadenylated tRNAs. The extent, kinetics and duration of tRNA polyadenylation were EtBr dose-dependent, with mitochondrial tRNAs differentially sensitive to the stress. RNA interference and inhibitor studies indicated that ongoing mitochondrial ATP synthesis, plus the mitochondrial poly(A) polymerase and SUV3 helicase were required for tRNA polyadenylation, while polynucleotide phosphorylase counteracted the process and was needed, along with SUV3, for degradation of the polyadenylated tRNAs. Doxycycline treatment inhibited both tRNA polyadenylation and turnover, suggesting a possible involvement of the mitoribosome, although other translational inhibitors had only minor effects. The dysfunctional tRNALeu(UUR) bearing the pathological A3243G mutation was constitutively polyadenylated at a low level, but this was markedly enhanced after doxycycline treatment. We propose that polyadenylation of structurally and functionally abnormal mitochondrial tRNAs entrains their PNPase/SUV3-mediated destruction, and that this pathway could play an important role in mitochondrial diseases associated with tRNA mutations.
Collapse
Affiliation(s)
- Marina Toompuu
- Faculty of Medicine and Life Sciences, BioMediTech Institute and Tampere University Hospital, FI-33014 University of Tampere, Finland
| | - Tea Tuomela
- Faculty of Medicine and Life Sciences, BioMediTech Institute and Tampere University Hospital, FI-33014 University of Tampere, Finland
| | - Pia Laine
- Institute of Biotechnology, FI-00014 University of Helsinki, Finland
| | - Lars Paulin
- Institute of Biotechnology, FI-00014 University of Helsinki, Finland
| | - Eric Dufour
- Faculty of Medicine and Life Sciences, BioMediTech Institute and Tampere University Hospital, FI-33014 University of Tampere, Finland
| | - Howard T Jacobs
- Faculty of Medicine and Life Sciences, BioMediTech Institute and Tampere University Hospital, FI-33014 University of Tampere, Finland.,Institute of Biotechnology, FI-00014 University of Helsinki, Finland
| |
Collapse
|
6
|
Transcription, Processing, and Decay of Mitochondrial RNA in Health and Disease. Int J Mol Sci 2019; 20:ijms20092221. [PMID: 31064115 PMCID: PMC6540609 DOI: 10.3390/ijms20092221] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/01/2019] [Accepted: 05/03/2019] [Indexed: 12/16/2022] Open
Abstract
Although the large majority of mitochondrial proteins are nuclear encoded, for their correct functioning mitochondria require the expression of 13 proteins, two rRNA, and 22 tRNA codified by mitochondrial DNA (mtDNA). Once transcribed, mitochondrial RNA (mtRNA) is processed, mito-ribosomes are assembled, and mtDNA-encoded proteins belonging to the respiratory chain are synthesized. These processes require the coordinated spatio-temporal action of several enzymes, and many different factors are involved in the regulation and control of protein synthesis and in the stability and turnover of mitochondrial RNA. In this review, we describe the essential steps of mitochondrial RNA synthesis, maturation, and degradation, the factors controlling these processes, and how the alteration of these processes is associated with human pathologies.
Collapse
|
7
|
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.
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
Warkocki Z, Liudkovska V, Gewartowska O, Mroczek S, Dziembowski A. Terminal nucleotidyl transferases (TENTs) in mammalian RNA metabolism. Philos Trans R Soc Lond B Biol Sci 2018; 373:rstb.2018.0162. [PMID: 30397099 PMCID: PMC6232586 DOI: 10.1098/rstb.2018.0162] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2018] [Indexed: 12/15/2022] Open
Abstract
In eukaryotes, almost all RNA species are processed at their 3′ ends and most mRNAs are polyadenylated in the nucleus by canonical poly(A) polymerases. In recent years, several terminal nucleotidyl transferases (TENTs) including non-canonical poly(A) polymerases (ncPAPs) and terminal uridyl transferases (TUTases) have been discovered. In contrast to canonical polymerases, TENTs' functions are more diverse; some, especially TUTases, induce RNA decay while others, such as cytoplasmic ncPAPs, activate translationally dormant deadenylated mRNAs. The mammalian genome encodes 11 different TENTs. This review summarizes the current knowledge about the functions and mechanisms of action of these enzymes. This article is part of the theme issue ‘5′ and 3′ modifications controlling RNA degradation’.
Collapse
Affiliation(s)
- Zbigniew Warkocki
- Department of RNA Metabolism, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznan, Poland
| | - Vladyslava Liudkovska
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Pawinskiego 5a, 02-106 Warsaw, Poland
| | - Olga Gewartowska
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Pawinskiego 5a, 02-106 Warsaw, Poland
| | - Seweryn Mroczek
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Pawinskiego 5a, 02-106 Warsaw, Poland
| | - Andrzej Dziembowski
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland .,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Pawinskiego 5a, 02-106 Warsaw, Poland
| |
Collapse
|
10
|
Furuya N, Kakuta S, Sumiyoshi K, Ando M, Nonaka R, Suzuki A, Kazuno S, Saiki S, Hattori N. NDP52 interacts with mitochondrial RNA poly(A) polymerase to promote mitophagy. EMBO Rep 2018; 19:embr.201846363. [PMID: 30309841 DOI: 10.15252/embr.201846363] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 09/10/2018] [Accepted: 09/11/2018] [Indexed: 02/06/2023] Open
Abstract
Parkin-mediated mitophagy is a quality control pathway that selectively removes damaged mitochondria via the autophagic machinery. Autophagic receptors, which interact with ubiquitin and Atg8 family proteins, contribute to the recognition of damaged mitochondria by autophagosomes. NDP52, an autophagy receptor, is required for autophagic engulfment of damaged mitochondria during mitochondrial uncoupler treatment. The N-terminal SKICH domain and C-terminal zinc finger motif of NDP52 are both required for its function in mitophagy. While the zinc finger motif contributes to poly-ubiquitin binding, the function of the SKICH domain remains unclear. Here, we show that NDP52 interacts with mitochondrial RNA poly(A) polymerase (MTPAP) via the SKICH domain. During mitophagy, NDP52 invades depolarized mitochondria and interacts with MTPAP dependent on the proteasome but independent of ubiquitin binding. Loss of MTPAP reduces NDP52-mediated mitophagy, and the NDP52-MTPAP complex attracts more LC3 than NDP52 alone. These results indicate that NDP52 and MTPAP form an autophagy receptor complex, which enhances autophagic elimination of damaged mitochondria.
Collapse
Affiliation(s)
- Norihiko Furuya
- Division for Development of Autophagy Modulating Drugs, Juntendo University Graduate School of Medicine, Tokyo, Japan .,Department of Neuroscience for Neurodegenerative Disorders, Juntendo University Graduate School of Medicine, Tokyo, Japan.,Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Soichiro Kakuta
- Laboratory of Morphology and Image Analysis, Biomedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.,Department of Cellular and Molecular Neuropathology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Katsuhiko Sumiyoshi
- Department of Health and Nutrition Collage of Human Science, Tokiwa University, Ibaraki, Japan.,Department of Cardiovascular Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Maya Ando
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Risa Nonaka
- Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Ayami Suzuki
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Saiko Kazuno
- Laboratory of Proteomics and Biomolecular Science, Research Support Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Shinji Saiki
- Division for Development of Autophagy Modulating Drugs, Juntendo University Graduate School of Medicine, Tokyo, Japan.,Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Nobutaka Hattori
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| |
Collapse
|
11
|
Mitochondrial transcription and translation: overview. Essays Biochem 2018; 62:309-320. [PMID: 30030363 PMCID: PMC6056719 DOI: 10.1042/ebc20170102] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/14/2018] [Accepted: 05/14/2018] [Indexed: 12/13/2022]
Abstract
Mitochondria are the major source of ATP in the cell. Five multi-subunit complexes in the inner membrane of the organelle are involved in the oxidative phosphorylation required for ATP production. Thirteen subunits of these complexes are encoded by the mitochondrial genome often referred to as mtDNA. For this reason, the expression of mtDNA is vital for the assembly and functioning of the oxidative phosphorylation complexes. Defects of the mechanisms regulating mtDNA gene expression have been associated with deficiencies in assembly of these complexes, resulting in mitochondrial diseases. Recently, numerous factors involved in these processes have been identified and characterized leading to a deeper understanding of the mechanisms that underlie mitochondrial diseases.
Collapse
|
12
|
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.
Collapse
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
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
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: 27] [Impact Index Per Article: 3.9] [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.
Collapse
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
| |
Collapse
|
15
|
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.
Collapse
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
| |
Collapse
|
16
|
Bratic A, Clemente P, Calvo-Garrido J, Maffezzini C, Felser A, Wibom R, Wedell A, Freyer C, Wredenberg A. Mitochondrial Polyadenylation Is a One-Step Process Required for mRNA Integrity and tRNA Maturation. PLoS Genet 2016; 12:e1006028. [PMID: 27176048 PMCID: PMC4866704 DOI: 10.1371/journal.pgen.1006028] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/14/2016] [Indexed: 12/20/2022] Open
Abstract
Polyadenylation has well characterised roles in RNA turnover and translation in a variety of biological systems. While polyadenylation on mitochondrial transcripts has been suggested to be a two-step process required to complete translational stop codons, its involvement in mitochondrial RNA turnover is less well understood. We studied knockdown and knockout models of the mitochondrial poly(A) polymerase (MTPAP) in Drosophila melanogaster and demonstrate that polyadenylation of mitochondrial mRNAs is exclusively performed by MTPAP. Further, our results show that mitochondrial polyadenylation does not regulate mRNA stability but protects the 3' terminal integrity, and that despite a lack of functioning 3' ends, these trimmed transcripts are translated, suggesting that polyadenylation is not required for mitochondrial translation. Additionally, loss of MTPAP leads to reduced steady-state levels and disturbed maturation of tRNACys, indicating that polyadenylation in mitochondria might be important for the stability and maturation of specific tRNAs. The polyadenylation of cellular RNAs is a well-studied signal for gene expression, with a defined function in either RNA turnover or translation, in the majority of systems. In mammalian mitochondria the role of polyadenylation is less clear, and can to date only be attributed to completing the translational stop signal on several mitochondrial transcripts. Previous work though demonstrated that mitochondrial polyadenylation requires a certain length and shortening of the poly(A) tail signal has detrimental effects on mitochondrial function. In this study we deleted the mitochondrial polymerase responsible for polyadenylation in the fly, Drosophila melanogaster, and demonstrate that the mitochondrial poly(A) tail is essential for preserving the 3’ ends of mitochondrial transcripts, with no other enzyme capable of completing stop signals. Our study also shows that polyadenylation does not regulate transcript stability nor is it required for translation, but might be involved in the maturation of certain mitochondrial tRNAs. We therefore conclude that besides completing translational stop signals, mitochondrial polyadenylation protects the 3’ termini from degradation.
Collapse
Affiliation(s)
- Ana Bratic
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Paula Clemente
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Javier Calvo-Garrido
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Camilla Maffezzini
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Andrea Felser
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Rolf Wibom
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Anna Wedell
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Christoph Freyer
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
- * E-mail: (CF); (AW)
| | - Anna Wredenberg
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
- * E-mail: (CF); (AW)
| |
Collapse
|
17
|
Fiedler M, Rossmanith W, Wahle E, Rammelt C. Mitochondrial poly(A) polymerase is involved in tRNA repair. Nucleic Acids Res 2015; 43:9937-49. [PMID: 26354863 PMCID: PMC4787750 DOI: 10.1093/nar/gkv891] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 08/26/2015] [Indexed: 11/12/2022] Open
Abstract
Transcription of the mitochondrial genome results in polycistronic precursors, which are processed mainly by the release of tRNAs interspersed between rRNAs and mRNAs. In many metazoan mitochondrial genomes some tRNA genes overlap with downstream genes; in the case of human mitochondria the genes for tRNATyr and tRNACys overlap by one nucleotide. It has previously been shown that processing of the common precursor releases an incomplete tRNATyr lacking the 3′-adenosine. The 3′-terminal adenosine has to be added before addition of the CCA end and subsequent aminoacylation. We show that the mitochondrial poly(A) polymerase (mtPAP) is responsible for this A addition. In vitro, a tRNATyr lacking the discriminator is a substrate for mtPAP. In vivo, an altered mtPAP protein level affected tRNATyr maturation, as shown by sequencing the 3′ ends of mitochondrial tRNAs. Complete repair could be reconstituted in vitro with three enzymes: mtPAP frequently added more than one A to the 3′ end of the truncated tRNA, and either the mitochondrial deadenylase PDE12 or the endonuclease RNase Z trimmed the oligo(A) tail to a single A before CCA addition. An enzyme machinery that evolved primarily for other purposes thus allows to tolerate the frequent evolutionary occurrence of gene overlaps.
Collapse
Affiliation(s)
- Mario Fiedler
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, 06099 Halle, Germany
| | - Walter Rossmanith
- Center for Anatomy & Cell Biology, Medical University of Vienna, 1090 Vienna, Austria
| | - Elmar Wahle
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, 06099 Halle, Germany
| | - Christiane Rammelt
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, 06099 Halle, Germany
| |
Collapse
|
18
|
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.
Collapse
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
| |
Collapse
|
19
|
Van Haute L, Pearce SF, Powell CA, D’Souza AR, Nicholls TJ, Minczuk M. Mitochondrial transcript maturation and its disorders. J Inherit Metab Dis 2015; 38:655-80. [PMID: 26016801 PMCID: PMC4493943 DOI: 10.1007/s10545-015-9859-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 04/27/2015] [Accepted: 04/29/2015] [Indexed: 11/03/2022]
Abstract
Mitochondrial respiratory chain deficiencies exhibit a wide spectrum of clinical presentations owing to defective mitochondrial energy production through oxidative phosphorylation. These defects can be caused by either mutations in the mitochondrial DNA (mtDNA) or mutations in nuclear genes coding for mitochondrially-targeted proteins. The underlying pathomechanisms can affect numerous pathways involved in mitochondrial biology including expression of mtDNA-encoded genes. Expression of the mitochondrial genes is extensively regulated at the post-transcriptional stage and entails nucleolytic cleavage of precursor RNAs, RNA nucleotide modifications, RNA polyadenylation, RNA quality and stability control. These processes ensure proper mitochondrial RNA (mtRNA) function, and are regulated by dedicated, nuclear-encoded enzymes. Recent growing evidence suggests that mutations in these nuclear genes, leading to incorrect maturation of RNAs, are a cause of human mitochondrial disease. Additionally, mutations in mtDNA-encoded genes may also affect RNA maturation and are frequently associated with human disease. We review the current knowledge on a subset of nuclear-encoded genes coding for proteins involved in mitochondrial RNA maturation, for which genetic variants impacting upon mitochondrial pathophysiology have been reported. Also, primary pathological mtDNA mutations with recognised effects upon RNA processing are described.
Collapse
Affiliation(s)
| | - Sarah F. Pearce
- MRC Mitochondrial Biology Unit, Hills Road, Cambridge, CB2 0XY UK
| | | | - Aaron R. D’Souza
- MRC Mitochondrial Biology Unit, Hills Road, Cambridge, CB2 0XY UK
| | - Thomas J. Nicholls
- MRC Mitochondrial Biology Unit, Hills Road, Cambridge, CB2 0XY UK
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Michal Minczuk
- MRC Mitochondrial Biology Unit, Hills Road, Cambridge, CB2 0XY UK
| |
Collapse
|
20
|
Priet S, Lartigue A, Debart F, Claverie JM, Abergel C. mRNA maturation in giant viruses: variation on a theme. Nucleic Acids Res 2015; 43:3776-88. [PMID: 25779049 PMCID: PMC4402537 DOI: 10.1093/nar/gkv224] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 03/03/2015] [Accepted: 03/04/2015] [Indexed: 12/02/2022] Open
Abstract
Giant viruses from the Mimiviridae family replicate entirely in their host cytoplasm where their genes are transcribed by a viral transcription apparatus. mRNA polyadenylation uniquely occurs at hairpin-forming palindromic sequences terminating viral transcripts. Here we show that a conserved gene cluster both encode the enzyme responsible for the hairpin cleavage and the viral polyA polymerases (vPAP). Unexpectedly, the vPAPs are homodimeric and uniquely self-processive. The vPAP backbone structures exhibit a symmetrical architecture with two subdomains sharing a nucleotidyltransferase topology, suggesting that vPAPs originate from an ancestral duplication. A Poxvirus processivity factor homologue encoded by Megavirus chilensis displays a conserved 5'-GpppA 2'O methyltransferase activity but is also able to internally methylate the mRNAs' polyA tails. These findings elucidate how the arm wrestling between hosts and their viruses to access the translation machinery is taking place in Mimiviridae.
Collapse
Affiliation(s)
- Stéphane Priet
- Architecture et Fonction des Macromolécules Biologiques, CNRS UMR 7257, Aix-Marseille Université, 163 Avenue de Luminy, Case 932, 13288 Marseille cedex 9, France
| | - Audrey Lartigue
- Structural and Genomic Information Laboratory, UMR 7256 (IMM FR 3479) CNRS Aix-Marseille Université, 163 Avenue de Luminy, Case 934, 13288 Marseille cedex 9, France
| | - Françoise Debart
- IBMM, UMR 5247, CNRS-UM1-UM2, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier, France
| | - Jean-Michel Claverie
- Structural and Genomic Information Laboratory, UMR 7256 (IMM FR 3479) CNRS Aix-Marseille Université, 163 Avenue de Luminy, Case 934, 13288 Marseille cedex 9, France APHM, FR-13385 Marseille, France
| | - Chantal Abergel
- Structural and Genomic Information Laboratory, UMR 7256 (IMM FR 3479) CNRS Aix-Marseille Université, 163 Avenue de Luminy, Case 934, 13288 Marseille cedex 9, France
| |
Collapse
|
21
|
Rüegger S, Miki TS, Hess D, Großhans H. The ribonucleotidyl transferase USIP-1 acts with SART3 to promote U6 snRNA recycling. Nucleic Acids Res 2015; 43:3344-57. [PMID: 25753661 PMCID: PMC4381082 DOI: 10.1093/nar/gkv196] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 02/24/2015] [Indexed: 02/02/2023] Open
Abstract
The spliceosome is a large molecular machine that serves to remove the intervening sequences that are present in most eukaryotic pre-mRNAs. At its core are five small nuclear ribonucleoprotein complexes, the U1, U2, U4, U5 and U6 snRNPs, which undergo dynamic rearrangements during splicing. Their reutilization for subsequent rounds of splicing requires reversion to their original configurations, but little is known about this process. Here, we show that ZK863.4/USIP-1 (U Six snRNA-Interacting Protein-1) is a ribonucleotidyl transferase that promotes accumulation of the Caenorhabditis elegans U6 snRNA. Endogenous USIP-1–U6 snRNA complexes lack the Lsm proteins that constitute the protein core of the U6 snRNP, but contain the U6 snRNP recycling factor SART3/B0035.12. Furthermore, co-immunoprecipitation experiments suggest that SART3 but not USIP-1 occurs also in a separate complex containing both the U4 and U6 snRNPs. Based on this evidence, genetic interaction between usip-1 and sart-3, and the apparent dissociation of Lsm proteins from the U6 snRNA during spliceosome activation, we propose that USIP-1 functions upstream of SART3 to promote U6 snRNA recycling.
Collapse
Affiliation(s)
- Stefan Rüegger
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland University of Basel, Petersplatz 1, CH-4003 Basel, Switzerland
| | - Takashi S Miki
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Daniel Hess
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Helge Großhans
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| |
Collapse
|
22
|
Wilson WC, Hornig-Do HT, Bruni F, Chang JH, Jourdain AA, Martinou JC, Falkenberg M, Spåhr H, Larsson NG, Lewis RJ, Hewitt L, Baslé A, Cross HE, Tong L, Lebel RR, Crosby AH, Chrzanowska-Lightowlers ZMA, Lightowlers RN. A human mitochondrial poly(A) polymerase mutation reveals the complexities of post-transcriptional mitochondrial gene expression. Hum Mol Genet 2014; 23:6345-55. [PMID: 25008111 PMCID: PMC4222368 DOI: 10.1093/hmg/ddu352] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The p.N478D missense mutation in human mitochondrial poly(A) polymerase (mtPAP) has previously been implicated in a form of spastic ataxia with optic atrophy. In this study, we have investigated fibroblast cell lines established from family members. The homozygous mutation resulted in the loss of polyadenylation of all mitochondrial transcripts assessed; however, oligoadenylation was retained. Interestingly, this had differential effects on transcript stability that were dependent on the particular species of transcript. These changes were accompanied by a severe loss of oxidative phosphorylation complexes I and IV, and perturbation of de novo mitochondrial protein synthesis. Decreases in transcript polyadenylation and in respiratory chain complexes were effectively rescued by overexpression of wild-type mtPAP. Both mutated and wild-type mtPAP localized to the mitochondrial RNA-processing granules thereby eliminating mislocalization as a cause of defective polyadenylation. In vitro polyadenylation assays revealed severely compromised activity by the mutated protein, which generated only short oligo(A) extensions on RNA substrates, irrespective of RNA secondary structure. The addition of LRPPRC/SLIRP, a mitochondrial RNA-binding complex, enhanced activity of the wild-type mtPAP resulting in increased overall tail length. The LRPPRC/SLIRP effect although present was less marked with mutated mtPAP, independent of RNA secondary structure. We conclude that (i) the polymerase activity of mtPAP can be modulated by the presence of LRPPRC/SLIRP, (ii) N478D mtPAP mutation decreases polymerase activity and (iii) the alteration in poly(A) length is sufficient to cause dysregulation of post-transcriptional expression and the pathogenic lack of respiratory chain complexes.
Collapse
Affiliation(s)
- William C Wilson
- Wellcome Trust Centre for Mitochondrial Research, Institute for Ageing and Health
| | - Hue-Tran Hornig-Do
- Wellcome Trust Centre for Mitochondrial Research, Institute for Ageing and Health
| | - Francesco Bruni
- Wellcome Trust Centre for Mitochondrial Research, Institute for Ageing and Health
| | - Jeong Ho Chang
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Alexis A Jourdain
- Department of Cell Biology, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Genève 4, Switzerland
| | - Jean-Claude Martinou
- Department of Cell Biology, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Genève 4, Switzerland
| | - Maria Falkenberg
- Department of Biochemistry and Cell Biology, University of Göteborg, Box 440, 40530 Göteborg, Sweden
| | - Henrik Spåhr
- Max Planck Institute for Biology of Ageing, Gleueler Strasse 50a, D-50931 Cologne, Germany
| | - Nils-Göran Larsson
- Max Planck Institute for Biology of Ageing, Gleueler Strasse 50a, D-50931 Cologne, Germany
| | | | | | - Arnaud Baslé
- Institute for Cell and Molecular Biosciences and
| | - Harold E Cross
- Department of Ophthalmology, University of Arizona School of Medicine, Tucson, AZ 85711, USA
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Robert R Lebel
- Center for Behavior, Development, and Genetics, Medical Genetics, SUNY Upstate Medical University, Syracuse, NY 13210, USA and
| | - Andrew H Crosby
- Molecular Genetics, University of Exeter Medical School, Royal Devon and Exeter Hospital, Barrack Road, Exeter EX2 5DW, UK
| | - Zofia M A Chrzanowska-Lightowlers
- Wellcome Trust Centre for Mitochondrial Research, Institute for Cell and Molecular Biosciences, Newcastle University Medical School, Newcastle upon Tyne NE2 4HH, UK,
| | - Robert N Lightowlers
- Wellcome Trust Centre for Mitochondrial Research, Institute for Cell and Molecular Biosciences, Newcastle University Medical School, Newcastle upon Tyne NE2 4HH, UK,
| |
Collapse
|
23
|
Demir O, Labaied M, Merritt C, Stuart K, Amaro RE. Computer-aided discovery of Trypanosoma brucei RNA-editing terminal uridylyl transferase 2 inhibitors. Chem Biol Drug Des 2014; 84:131-9. [PMID: 24903413 DOI: 10.1111/cbdd.12302] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/12/2013] [Accepted: 02/07/2014] [Indexed: 11/27/2022]
Abstract
Human African trypanosomiasis (HAT) is a major health problem in sub-Saharan Africa caused by Trypanosoma brucei infection. Current HAT drugs are difficult to administer and not effective against all parasite species at different stages of the disease which indicates an unmet pharmaceutical need. TbRET2 is an indispensable enzyme for the parasite and is targeted here using a computational approach that combines molecular dynamics simulations and virtual screening. The compounds prioritized are then tested in T. brucei via Alamar blue cell viability assays. This work identified 20 drug-like compounds which are candidates for further testing in the drug discovery process.
Collapse
Affiliation(s)
- Ozlem Demir
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093, USA
| | | | | | | | | |
Collapse
|
24
|
Wang DDH, Guo XE, Modrek AS, Chen CF, Chen PL, Lee WH. Helicase SUV3, polynucleotide phosphorylase, and mitochondrial polyadenylation polymerase form a transient complex to modulate mitochondrial mRNA polyadenylated tail lengths in response to energetic changes. J Biol Chem 2014; 289:16727-35. [PMID: 24770417 DOI: 10.1074/jbc.m113.536540] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mammalian mitochondrial mRNA (mt-mRNA) transcripts are polyadenylated at the 3' end with different lengths. The SUV3·PNPase complex and mtPAP have been shown to degrade and polyadenylate mt mRNA, respectively. How these two opposite actions are coordinated to modulate mt-mRNA poly(A) lengths is of interest to pursue. Here, we demonstrated that a fraction of the SUV3·PNPase complex interacts with mitochondrial polyadenylation polymerase (mtPAP) under low mitochondrial matrix inorganic phosphate (Pi) conditions. In vitro binding experiments using purified proteins suggested that SUV3 binds to mtPAP through the N-terminal region around amino acids 100-104, distinctive from the C-terminal region around amino acids 510-514 of SUV3 for PNPase binding. mtPAP does not interact with PNPase directly, and SUV3 served as a bridge capable of simultaneously binding with mtPAP and PNPase. The complex consists of a SUV3 dimer, a mtPAP dimer, and a PNPase trimer, based on the molecular sizing experiments. Mechanistically, SUV3 provides a robust single strand RNA binding domain to enhance the polyadenylation activity of mtPAP. Furthermore, purified SUV3·PNPase·mtPAP complex is capable of lengthening or shortening the RNA poly(A) tail lengths in low or high Pi/ATP ratios, respectively. Consistently, the poly(A) tail lengths of mt-mRNA transcripts can be lengthened or shortened by altering the mitochondrial matrix Pi levels via selective inhibition of the electron transport chain or ATP synthase, respectively. Taken together, these results suggested that SUV3·PNPase·mtPAP form a transient complex to modulate mt-mRNA poly(A) tail lengths in response to cellular energy changes.
Collapse
Affiliation(s)
- Dennis Ding-Hwa Wang
- From the Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, California 92697 and
| | - Xuning Emily Guo
- From the Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, California 92697 and
| | - Aram Sandaldjian Modrek
- From the Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, California 92697 and
| | - Chi-Fen Chen
- From the Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, California 92697 and
| | - Phang-Lang Chen
- From the Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, California 92697 and
| | - Wen-Hwa Lee
- From the Department of Biological Chemistry, School of Medicine, University of California Irvine, Irvine, California 92697 and the Graduate Institute of Clinical Medical Science, China Medical University, Taichung 40402, Taiwan
| |
Collapse
|
25
|
Martin NT, Nakamura K, Paila U, Woo J, Brown C, Wright JA, Teraoka SN, Haghayegh S, McCurdy D, Schneider M, Hu H, Quinlan AR, Gatti RA, Concannon P. Homozygous mutation of MTPAP causes cellular radiosensitivity and persistent DNA double-strand breaks. Cell Death Dis 2014; 5:e1130. [PMID: 24651433 PMCID: PMC3973239 DOI: 10.1038/cddis.2014.99] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 01/29/2014] [Accepted: 02/03/2014] [Indexed: 02/03/2023]
Abstract
The study of rare human syndromes characterized by radiosensitivity has been instrumental in identifying novel proteins and pathways involved in DNA damage responses to ionizing radiation. In the present study, a mutation in mitochondrial poly-A-polymerase (MTPAP), not previously recognized for its role in the DNA damage response, was identified by exome sequencing and subsequently associated with cellular radiosensitivity. Cell lines derived from two patients with the homozygous MTPAP missense mutation were radiosensitive, and this radiosensitivity could be abrogated by transfection of wild-type mtPAP cDNA into mtPAP-deficient cell lines. Further analysis of the cellular phenotype revealed delayed DNA repair, increased levels of DNA double-strand breaks, increased reactive oxygen species (ROS), and increased cell death after irradiation (IR). Pre-IR treatment of cells with the potent anti-oxidants, α-lipoic acid and n-acetylcysteine, was sufficient to abrogate the DNA repair and clonogenic survival defects. Our results firmly establish that mutation of the MTPAP gene results in a cellular phenotype of increased DNA damage, reduced repair kinetics, increased cell death by apoptosis, and reduced clonogenic survival after exposure to ionizing radiation, suggesting a pathogenesis that involves the disruption of ROS homeostasis.
Collapse
Affiliation(s)
- N T Martin
- 1] UCLA Department of Pathology and Laboratory Medicine, MacDonald Research Laboratories, Los Angeles, CA, USA [2] UCLA Biomedical Physics Interdepartmental Graduate Program, Los Angeles, CA, USA
| | - K Nakamura
- UCLA Department of Pathology and Laboratory Medicine, MacDonald Research Laboratories, Los Angeles, CA, USA
| | - U Paila
- Department of Public Health Sciences, Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - J Woo
- UCLA Department of Pathology and Laboratory Medicine, MacDonald Research Laboratories, Los Angeles, CA, USA
| | - C Brown
- UCLA Department of Pathology and Laboratory Medicine, MacDonald Research Laboratories, Los Angeles, CA, USA
| | - J A Wright
- Genetics Institute, University of Florida, Gainesville, FL, USA
| | - S N Teraoka
- Genetics Institute, University of Florida, Gainesville, FL, USA
| | - S Haghayegh
- UCLA Department of Pathology and Laboratory Medicine, MacDonald Research Laboratories, Los Angeles, CA, USA
| | - D McCurdy
- UCLA Department of Pediatrics, Los Angeles, CA, USA
| | | | - H Hu
- UCLA Department of Pathology and Laboratory Medicine, MacDonald Research Laboratories, Los Angeles, CA, USA
| | - A R Quinlan
- Department of Public Health Sciences, Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - R A Gatti
- 1] UCLA Department of Pathology and Laboratory Medicine, MacDonald Research Laboratories, Los Angeles, CA, USA [2] UCLA Biomedical Physics Interdepartmental Graduate Program, Los Angeles, CA, USA [3] UCLA Department of Human Genetics, Los Angeles, CA, USA
| | - P Concannon
- 1] Genetics Institute, University of Florida, Gainesville, FL, USA [2] Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL, USA
| |
Collapse
|
26
|
Jurado AR, Tan D, Jiao X, Kiledjian M, Tong L. Structure and function of pre-mRNA 5'-end capping quality control and 3'-end processing. Biochemistry 2014; 53:1882-98. [PMID: 24617759 PMCID: PMC3977584 DOI: 10.1021/bi401715v] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Messenger RNA precursors (pre-mRNAs)
are produced as the nascent
transcripts of RNA polymerase II (Pol II) in eukaryotes and must undergo
extensive maturational processing, including 5′-end capping,
splicing, and 3′-end cleavage and polyadenylation. This review
will summarize the structural and functional information reported
over the past few years on the large machinery required for the 3′-end
processing of most pre-mRNAs, as well as the distinct machinery for
the 3′-end processing of replication-dependent histone pre-mRNAs,
which have provided great insights into the proteins and their subcomplexes
in these machineries. Structural and biochemical studies have also
led to the identification of a new class of enzymes (the DXO family
enzymes) with activity toward intermediates of the 5′-end capping
pathway. Functional studies demonstrate that these enzymes are part
of a novel quality surveillance mechanism for pre-mRNA 5′-end
capping. Incompletely capped pre-mRNAs are produced in yeast and human
cells, in contrast to the general belief in the field that capping
always proceeds to completion, and incomplete capping leads to defects
in splicing and 3′-end cleavage in human cells. The DXO family
enzymes are required for the detection and degradation of these defective
RNAs.
Collapse
Affiliation(s)
- Ashley R Jurado
- Department of Biological Sciences, Columbia University , New York, New York 10027, United States
| | | | | | | | | |
Collapse
|
27
|
Chang H, Lim J, Ha M, Kim VN. TAIL-seq: genome-wide determination of poly(A) tail length and 3' end modifications. Mol Cell 2014; 53:1044-52. [PMID: 24582499 DOI: 10.1016/j.molcel.2014.02.007] [Citation(s) in RCA: 312] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 12/23/2013] [Accepted: 02/03/2014] [Indexed: 01/05/2023]
Abstract
Global investigation of the 3' extremity of mRNA (3'-terminome), despite its importance in gene regulation, has not been feasible due to technical challenges associated with homopolymeric sequences and relative paucity of mRNA. We here develop a method, TAIL-seq, to sequence the very end of mRNA molecules. TAIL-seq allows us to measure poly(A) tail length at the genomic scale. Median poly(A) length is 50-100 nt in HeLa and NIH 3T3 cells. Poly(A) length correlates with mRNA half-life, but not with translational efficiency. Surprisingly, we discover widespread uridylation and guanylation at the downstream of poly(A) tail. The U tails are generally attached to short poly(A) tails (<25 nt), while the G tails are found mainly on longer poly(A) tails (>40 nt), implicating their generic roles in mRNA stability control. TAIL-seq is a potent tool to dissect dynamic control of mRNA turnover and translational control, and to discover unforeseen features of RNA cleavage and tailing.
Collapse
Affiliation(s)
- Hyeshik Chang
- Center for RNA Research, Institute for Basic Science, Seoul 151-742, Korea; School of Biological Sciences, Seoul National University, Seoul 151-742, Korea
| | - Jaechul Lim
- Center for RNA Research, Institute for Basic Science, Seoul 151-742, Korea; School of Biological Sciences, Seoul National University, Seoul 151-742, Korea
| | - Minju Ha
- Center for RNA Research, Institute for Basic Science, Seoul 151-742, Korea; School of Biological Sciences, Seoul National University, Seoul 151-742, Korea
| | - V Narry Kim
- Center for RNA Research, Institute for Basic Science, Seoul 151-742, Korea; School of Biological Sciences, Seoul National University, Seoul 151-742, Korea.
| |
Collapse
|
28
|
Rorbach J, Bobrowicz A, Pearce S, Minczuk M. Polyadenylation in bacteria and organelles. Methods Mol Biol 2014; 1125:211-27. [PMID: 24590792 DOI: 10.1007/978-1-62703-971-0_18] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Polyadenylation is a posttranscriptional modification present throughout all the kingdoms of life with important roles in regulation of RNA stability, translation, and quality control. Functions of polyadenylation in prokaryotic and organellar RNA metabolism are still not fully characterized, and poly(A) tails appear to play contrasting roles in different systems. Here we present a general overview of the polyadenylation process and the factors involved in its regulation, with an emphasis on the diverse functions of 3' end modification in the control of gene expression in different biological systems.
Collapse
Affiliation(s)
- Joanna Rorbach
- Mitochondrial Genetics Group, MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge, CB2 0XY, UK,
| | | | | | | |
Collapse
|
29
|
Pearce S, Nezich CL, Spinazzola A. Mitochondrial diseases: translation matters. Mol Cell Neurosci 2012; 55:1-12. [PMID: 22986124 DOI: 10.1016/j.mcn.2012.08.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 08/22/2012] [Accepted: 08/25/2012] [Indexed: 11/30/2022] Open
Abstract
Mitochondrial diseases comprise a heterogeneous group of disorders characterized by compromised energy production. Since the early days of mitochondrial medical genetics, it has been known that these can be caused by defects in mitochondrial protein synthesis. However, only in recent years have we begun to develop a broader picture of the array of proteins required for mitochondrial translation. With this new knowledge has come the realization that there are many more neurological and other, diseases attributable to impaired mitochondrial translation than previously thought. Perturbation of any part of this intricate machinery, from the primary sequence of transfer or ribosomal RNAs, to the proteolytic processing of ribosomal proteins, can cause mitochondrial dysfunction and disease. In this review we discuss the current understanding of the mechanisms and factors involved in mammalian mitochondrial translation, and the diverse pathologies resulting when it malfunctions. This article is part of a Special Issue entitled 'Mitochondrial function and dysfunction in neurodegeneration'.
Collapse
Affiliation(s)
- Sarah Pearce
- MRC Mitochondrial Biology Unit, Wellcome Trust-MRC Building, Hills Road Cambridge, CB2 0XY, UK
| | | | | |
Collapse
|
30
|
Chang JH, Tong L. Mitochondrial poly(A) polymerase and polyadenylation. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1819:992-7. [PMID: 22172994 PMCID: PMC3307840 DOI: 10.1016/j.bbagrm.2011.10.012] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 10/25/2011] [Accepted: 10/27/2011] [Indexed: 01/22/2023]
Abstract
Polyadenylation of mitochondrial RNAs in higher eukaryotic organisms have diverse effects on their function and metabolism. Polyadenylation completes the UAA stop codon of a majority of mitochondrial mRNAs in mammals, regulates the translation of the mRNAs, and has diverse effects on their stability. In contrast, polyadenylation of most mitochondrial mRNAs in plants leads to their degradation, consistent with the bacterial origin of this organelle. PAPD1 (mtPAP, TUTase1), a noncanonical poly(A) polymerase (ncPAP), is responsible for producing the poly(A) tails in mammalian mitochondria. The crystal structure of human PAPD1 was reported recently, offering molecular insights into its catalysis. This article is part of a Special Issue entitled: Mitochondrial Gene Expression.
Collapse
Affiliation(s)
- Jeong Ho Chang
- Department of Biological Sciences, Columbia University, New York, NY10027, USA
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, NY10027, USA
| |
Collapse
|
31
|
Lunde BM, Magler I, Meinhart A. Crystal structures of the Cid1 poly (U) polymerase reveal the mechanism for UTP selectivity. Nucleic Acids Res 2012; 40:9815-24. [PMID: 22885303 PMCID: PMC3479196 DOI: 10.1093/nar/gks740] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Polyuridylation is emerging as a ubiquitous post-translational modification with important roles in multiple aspects of RNA metabolism. These poly (U) tails are added by poly (U) polymerases with homology to poly (A) polymerases; nevertheless, the selection for UTP over ATP remains enigmatic. We report the structures of poly (U) polymerase Cid1 from Schizoscaccharomyces pombe alone and in complex with UTP, CTP, GTP and 3′-dATP. These structures reveal that each of the 4 nt can be accommodated at the active site; however, differences exist that suggest how the polymerase selects UTP over the other nucleotides. Furthermore, we find that Cid1 shares a number of common UTP recognition features with the kinetoplastid terminal uridyltransferases. Kinetic analysis of Cid1’s activity for its preferred substrates, UTP and ATP, reveal a clear preference for UTP over ATP. Ultimately, we show that a single histidine in the active site plays a pivotal role for poly (U) activity. Notably, this residue is typically replaced by an asparagine residue in Cid1-family poly (A) polymerases. By mutating this histidine to an asparagine residue in Cid1, we diminished Cid1’s activity for UTP addition and improved ATP incorporation, supporting that this residue is important for UTP selectivity.
Collapse
Affiliation(s)
- Bradley M Lunde
- Department of Biomolecular Mechanisms, Max-Planck-Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany
| | | | | |
Collapse
|
32
|
Rackham O, Mercer TR, Filipovska A. The human mitochondrial transcriptome and the RNA-binding proteins that regulate its expression. WILEY INTERDISCIPLINARY REVIEWS-RNA 2012; 3:675-95. [DOI: 10.1002/wrna.1128] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
33
|
Structural basis for the activity of a cytoplasmic RNA terminal uridylyl transferase. Nat Struct Mol Biol 2012; 19:782-787. [PMID: 22751018 DOI: 10.1038/nsmb.2329] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Accepted: 05/18/2012] [Indexed: 02/02/2023]
Abstract
Cytoplasmic terminal uridylyl transferases comprise a conserved family of enzymes that negatively regulate the stability or biological activity of a variety of eukaryotic RNAs, including mRNAs and tumor-suppressor let-7 microRNAs. Here we describe crystal structures of the Schizosaccharomyces pombe cytoplasmic terminal uridylyl transferase Cid1 in two apo conformers and bound to UTP. We demonstrate that a single histidine residue, conserved in mammalian Cid1 orthologs, is responsible for discrimination between UTP and ATP. We also describe a new high-affinity RNA substrate-binding mechanism of Cid1, which is essential for enzymatic activity and is mediated by three basic patches across the surface of the enzyme. Overall, our structures provide a basis for understanding the activity of Cid1 and a mechanism of UTP selectivity conserved in its human orthologs, suggesting potential implications for anticancer drug design.
Collapse
|
34
|
Demir Ö, Amaro RE. Elements of nucleotide specificity in the Trypanosoma brucei mitochondrial RNA editing enzyme RET2. J Chem Inf Model 2012; 52:1308-18. [PMID: 22512810 DOI: 10.1021/ci3001327] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The causative agent of African sleeping sickness, Trypanosoma brucei , undergoes an unusual mitochondrial RNA editing process that is essential for its survival. RNA editing terminal uridylyl transferase 2 of T. brucei (TbRET2) is an indispensable component of the editosome machinery that performs this editing. TbRET2 is required to maintain the vitality of both the insect and bloodstream forms of the parasite, and with its high-resolution crystal structure, it poses as a promising pharmaceutical target. Neither the exclusive requirement of uridine 5'-triphosphate (UTP) for catalysis, nor the RNA primer preference of TbRET2 is well-understood. Using all-atom explicitly solvated molecular dynamics (MD) simulations, we investigated the effect of UTP binding on TbRET2 structure and dynamics, as well as the determinants governing TbRET2's exclusive UTP preference. Through our investigations of various nucleoside triphosphate substrates (NTPs), we show that UTP preorganizes the binding site through an extensive water-mediated H-bonding network, bringing Glu424 and Arg144 side chains to an optimum position for RNA primer binding. In contrast, cytosine 5'-triphosphate (CTP) and adenosine 5'-triphosphate (ATP) cannot achieve this preorganization and thus preclude productive RNA primer binding. Additionally, we have located ligand-binding "hot spots" of TbRET2 based on the MD conformational ensembles and computational fragment mapping. TbRET2 reveals different binding pockets in the apo and UTP-bound MD simulations, which could be targeted for inhibitor design.
Collapse
Affiliation(s)
- Özlem Demir
- Department of Chemistry and Biochemistry, University of California , San Diego, 3234 Urey Hall, 9500 Gilman Drive, MC-0340 La Jolla, California 92093-0332, USA
| | | |
Collapse
|
35
|
Minasaki R, Eckmann CR. Subcellular specialization of multifaceted 3'end modifying nucleotidyltransferases. Curr Opin Cell Biol 2012; 24:314-22. [PMID: 22551970 DOI: 10.1016/j.ceb.2012.03.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 03/24/2012] [Accepted: 03/29/2012] [Indexed: 10/28/2022]
Abstract
While canonical 3'end modifications of mRNAs or tRNAs are well established, recent technological advances in RNA analysis have given us a glimpse of how widespread other types of distinctive 3'end modifications appear to be. Next to alternative nuclear or cytoplasmic polyadenylation mechanisms, evidence accumulated for a variety of 3'end mono-nucleotide and oligo-nucleotide additions of primarily adenosines or uracils on a variety of RNA species. Enzymes responsible for such non-templated additions are non-canonical RNA nucleotidyltransferases, which possess surprising flexibility in RNA substrate selection and enzymatic activity. We will highlight recent findings supporting the view that RNA nucleotidyltransferase activity, RNA target selection and sub-compartimentalization are spatially, temporally and physiologically regulated by dedicated co-factors. Along with the diversification of non-coding RNA classes, the evolutionary conservation of these multifaceted RNA modifiers underscores the prevalence and importance of diverse 3'end formation mechanisms.
Collapse
Affiliation(s)
- Ryuji Minasaki
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | | |
Collapse
|