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Chetverin AB. Alexander Spirin on Molecular Machines and Origin of Life. BIOCHEMISTRY (MOSCOW) 2021; 86:913-925. [PMID: 34488569 DOI: 10.1134/s0006297921080034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Once it was believed that ribosomal RNA encodes proteins, and GTP hydrolysis supplies the energy for protein synthesis. Everything has changed, when Alexander Spirin joined the science. It turned out that proteins are encoded by a completely different RNA, and GTP hydrolysis only accelerates the process already provided with energy. It was Spirin who first put forward the idea of a Brownian ratchet and explained how and why molecular machines could arise in the RNA world.
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Affiliation(s)
- Alexander B Chetverin
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
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2
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Weise LI, Heymann M, Mayr V, Mutschler H. Cell-free expression of RNA encoded genes using MS2 replicase. Nucleic Acids Res 2019; 47:10956-10967. [PMID: 31566241 PMCID: PMC6847885 DOI: 10.1093/nar/gkz817] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 09/03/2019] [Accepted: 09/12/2019] [Indexed: 01/05/2023] Open
Abstract
RNA replicases catalyse transcription and replication of viral RNA genomes. Of particular interest for in vitro studies are phage replicases due to their small number of host factors required for activity and their ability to initiate replication in the absence of any primers. However, the requirements for template recognition by most phage replicases are still only poorly understood. Here, we show that the active replicase of the archetypical RNA phage MS2 can be produced in a recombinant cell-free expression system. We find that the 3' terminal fusion of antisense RNAs with a domain derived from the reverse complement of the wild type MS2 genome generates efficient templates for transcription by the MS2 replicase. The new system enables DNA-independent gene expression both in batch reactions and in microcompartments. Finally, we demonstrate that MS2-based RNA-dependent transcription-translation reactions can be used to control DNA-dependent gene expression by encoding a viral DNA-dependent RNA polymerase on a MS2 RNA template. Our study sheds light on the template requirements of the MS2 replicase and paves the way for new in vitro applications including the design of genetic circuits combining both DNA- and RNA-encoded systems.
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Affiliation(s)
- Laura I Weise
- Biomimetic Systems, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
| | - Michael Heymann
- Dept. Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
| | - Viktoria Mayr
- Biomimetic Systems, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
| | - Hannes Mutschler
- Biomimetic Systems, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
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3
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Yao Y, Zhang W, Zhang M, Jin S, Guo Y, Zu Y, Ren K, Wang K, Chen G, Lou C, Wu Q. A Direct RNA-to-RNA Replication System for Enhanced Gene Expression in Bacteria. ACS Synth Biol 2019; 8:1067-1078. [PMID: 31070362 DOI: 10.1021/acssynbio.8b00521] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A long-standing objective of metabolic engineering has been to exogenously increase the expression of target genes. In this research, we proposed the permanent RNA replication system using DNA as a template to store genetic information in bacteria. We selected Qβ phage as the RNA replication prototype and made many improvements to achieve target gene expression enhancement directly by increasing mRNA abundance. First, we identified the endogenous gene Rnc, the knockout of which significantly improved the RNA replication efficiency. Second, we elucidated the essential elements for RNA replication and optimized the system to make it more easily applicable. Combined with optimization of the host cell and the system itself, we developed a stable RNA-to-RNA replication tool to directly increase the abundance of the target mRNA and subsequently the target protein. Furthermore, it was proven efficient in enhancing the expression of specific proteins and was demonstrated to be applicable in metabolic engineering. Our system has the potential to be combined with any of the existing methods for increasing gene expression.
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Affiliation(s)
- Yi Yao
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Wenhui Zhang
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Min Zhang
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shouhong Jin
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yingying Guo
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Peking-Tsinghua Center for Life Sciences, School of Life Science, Tsinghua University, Beijing 100084, China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
| | - Yumeng Zu
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Kang Ren
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Kun Wang
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Guoqiang Chen
- Peking-Tsinghua Center for Life Sciences, School of Life Science, Tsinghua University, Beijing 100084, China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
- MOE Key Lab of Industrial Biocatalysis, Tsinghua University, Beijing 100081, China
| | - Chunbo Lou
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering and Institute of Microbiology, State Key Laboratory of Microbial Resources, Institute of Microbiology Chinese Academy of Sciences, Beijing 100101, China
| | - Qiong Wu
- MOE Key Lab of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
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4
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Le Vay K, Weise LI, Libicher K, Mascarenhas J, Mutschler H. Templated Self‐Replication in Biomimetic Systems. ACTA ACUST UNITED AC 2019; 3:e1800313. [DOI: 10.1002/adbi.201800313] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/06/2019] [Indexed: 12/27/2022]
Affiliation(s)
- Kristian Le Vay
- Biomimetic SystemsMax Planck Institute of Biochemistry Martinsried Germany
| | - Laura Isabel Weise
- Biomimetic SystemsMax Planck Institute of Biochemistry Martinsried Germany
| | - Kai Libicher
- Biomimetic SystemsMax Planck Institute of Biochemistry Martinsried Germany
| | - Judita Mascarenhas
- Department of Systems and Synthetic MicrobiologyMax Planck Institute for Terrestrial Microbiology Marburg Germany
| | - Hannes Mutschler
- Biomimetic SystemsMax Planck Institute of Biochemistry Martinsried Germany
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5
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Chetverin AB. Thirty Years of Studies of Qβ Replicase: What Have We Learned and What Is Yet to Be Learned? BIOCHEMISTRY (MOSCOW) 2018; 83:S19-S32. [DOI: 10.1134/s0006297918140031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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6
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Gytz H, Mohr D, Seweryn P, Yoshimura Y, Kutlubaeva Z, Dolman F, Chelchessa B, Chetverin AB, Mulder FAA, Brodersen DE, Knudsen CR. Structural basis for RNA-genome recognition during bacteriophage Qβ replication. Nucleic Acids Res 2015; 43:10893-906. [PMID: 26578560 PMCID: PMC4678825 DOI: 10.1093/nar/gkv1212] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 10/28/2015] [Indexed: 01/19/2023] Open
Abstract
Upon infection of Escherichia coli by bacteriophage Qβ, the virus-encoded β-subunit recruits host translation elongation factors EF-Tu and EF-Ts and ribosomal protein S1 to form the Qβ replicase holoenzyme complex, which is responsible for amplifying the Qβ (+)-RNA genome. Here, we use X-ray crystallography, NMR spectroscopy, as well as sequence conservation, surface electrostatic potential and mutational analyses to decipher the roles of the β-subunit and the first two oligonucleotide-oligosaccharide-binding domains of S1 (OB1–2) in the recognition of Qβ (+)-RNA by the Qβ replicase complex. We show how three basic residues of the β subunit form a patch located adjacent to the OB2 domain, and use NMR spectroscopy to demonstrate for the first time that OB2 is able to interact with RNA. Neutralization of the basic residues by mutagenesis results in a loss of both the phage infectivity in vivo and the ability of Qβ replicase to amplify the genomic RNA in vitro. In contrast, replication of smaller replicable RNAs is not affected. Taken together, our data suggest that the β-subunit and protein S1 cooperatively bind the (+)-stranded Qβ genome during replication initiation and provide a foundation for understanding template discrimination during replication initiation.
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Affiliation(s)
- Heidi Gytz
- Department of Molecular Biology and Genetics, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Durita Mohr
- Department of Molecular Biology and Genetics, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Paulina Seweryn
- Department of Molecular Biology and Genetics, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Yuichi Yoshimura
- Interdisciplinary Nanoscience Centre (iNANO) and Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Zarina Kutlubaeva
- Institute of Protein Research of the Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Fleur Dolman
- Department of Molecular Biology and Genetics, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Bosene Chelchessa
- Department of Molecular Biology and Genetics, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Alexander B Chetverin
- Institute of Protein Research of the Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Frans A A Mulder
- Interdisciplinary Nanoscience Centre (iNANO) and Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Ditlev E Brodersen
- Department of Molecular Biology and Genetics, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Charlotte R Knudsen
- Department of Molecular Biology and Genetics, Aarhus University, DK-8000 Aarhus C, Denmark
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7
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Usui K, Ichihashi N, Yomo T. A design principle for a single-stranded RNA genome that replicates with less double-strand formation. Nucleic Acids Res 2015. [PMID: 26202975 PMCID: PMC4652763 DOI: 10.1093/nar/gkv742] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Single-stranded RNA (ssRNA) is the simplest form of genetic molecule and constitutes the genome in some viruses and presumably in primitive life-forms. However, an innate and unsolved problem regarding the ssRNA genome is formation of inactive double-stranded RNA (dsRNA) during replication. Here, we addressed this problem by focusing on the secondary structure. We systematically designed RNAs with various structures and observed dsRNA formation during replication using an RNA replicase (Qβ replicase). From the results, we extracted a simple rule regarding ssRNA genome replication with less dsRNA formation (less GC number in loops) and then designed an artificial RNA that encodes a domain of the β-galactosidase gene based on this rule. We also obtained evidence that this rule governs the natural genomes of all bacterial and most fungal viruses presently known. This study revealed one of the structural design principles of an ssRNA genome that replicates continuously with less dsRNA formation.
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Affiliation(s)
- Kimihito Usui
- Exploratory Research for Advanced Technology, Japan Science and Technology Agency, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Norikazu Ichihashi
- Exploratory Research for Advanced Technology, Japan Science and Technology Agency, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Tetsuya Yomo
- Exploratory Research for Advanced Technology, Japan Science and Technology Agency, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan Graduate School of Frontier Biosciences, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
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8
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Arai H, Nishigaki K, Nemoto N, Suzuki M, Husimi Y. Optimal terminal sequences for continuous or serial isothermal amplification of dsRNA with norovirus RNA replicase. Biophysics (Nagoya-shi) 2014; 10:15-23. [PMID: 27493494 PMCID: PMC4629653 DOI: 10.2142/biophysics.10.15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 02/10/2014] [Indexed: 12/01/2022] Open
Abstract
The norovirus RNA replicase (NV3D(pol), 56 kDa, single chain monomeric protein) can amplify double-stranded (ds) RNA isothermally. It will play an alternative role in the in vitro evolution against traditional Qβ RNA replicase, which cannot amplify dsRNA and consists of four subunits, three of which are borrowed from host E.coli. In order to identify the optimal 3'-terminal sequence of the RNA template for NV3D(pol), an in vitro selection using the serial transfer was performed for a random library having the 3'-terminal sequence of ---UUUUUUNNNN-3'. The population landscape on the 4-dimensional sequence space of the 17(th) round of transfer gave a main peak around ---CAAC-3'. In the preceding studies on the batch amplification reaction starting from a single-stranded RNA, a template with 3'-terminal C-stretch was amplified effectively. It was confirmed that in the batch amplification the ---CCC-3' was much more effective than the ---CAAC-3', but in the serial transfer condition in which the ----CAAC-3' was sustained stably, the ---CCC-3' was washed out. Based on these results we proposed the existence of the "shuttle mode" replication of dsRNA. We also proposed the optimal terminal sequences of RNA for in vitro evolution with NV3D(pol).
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Affiliation(s)
- Hidenao Arai
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Koichi Nishigaki
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Naoto Nemoto
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Miho Suzuki
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Yuzuru Husimi
- Innovative Research Organization, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
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9
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Usui K, Ichihashi N, Kazuta Y, Matsuura T, Yomo T. Effects of ribosomes on the kinetics of Qβ replication. FEBS Lett 2013; 588:117-23. [PMID: 24269228 DOI: 10.1016/j.febslet.2013.11.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 11/05/2013] [Accepted: 11/12/2013] [Indexed: 10/26/2022]
Abstract
Bacteriophage Qβ utilizes some host cell translation factors during replication. Previously, we constructed a kinetic model that explains replication of long RNA molecules by Qβ replicase. Here, we expanded the previous kinetic model to include the effects of ribosome concentration on RNA replication. The expanded model quantitatively explained single- and double-strand formation kinetics during replication with various ribosome concentrations for two artificial long RNAs. This expanded model and the knowledge obtained in this study provide useful frameworks to understand the precise replication mechanism of Qβ replicase with ribosomes and to design amplifiable RNA genomes in translation-coupling systems.
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Affiliation(s)
- Kimihito Usui
- Japan Science and Technology Agency (JST), ERATO, Yomo Dynamical Micro-scale Reaction Environment Project, Yamadaoka 1-5, Suita, Osaka, Japan
| | - Norikazu Ichihashi
- Japan Science and Technology Agency (JST), ERATO, Yomo Dynamical Micro-scale Reaction Environment Project, Yamadaoka 1-5, Suita, Osaka, Japan; Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, Yamadaoka 1-5, Suita, Osaka, Japan
| | - Yasuaki Kazuta
- Japan Science and Technology Agency (JST), ERATO, Yomo Dynamical Micro-scale Reaction Environment Project, Yamadaoka 1-5, Suita, Osaka, Japan
| | - Tomoaki Matsuura
- Japan Science and Technology Agency (JST), ERATO, Yomo Dynamical Micro-scale Reaction Environment Project, Yamadaoka 1-5, Suita, Osaka, Japan; Graduate School of Engineering, Osaka University, Yamadaoka 1-5, Suita, Osaka, Japan
| | - Tetsuya Yomo
- Japan Science and Technology Agency (JST), ERATO, Yomo Dynamical Micro-scale Reaction Environment Project, Yamadaoka 1-5, Suita, Osaka, Japan; Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, Yamadaoka 1-5, Suita, Osaka, Japan; Graduate School of Frontier Biosciences, Osaka University, Yamadaoka 1-5, Suita, Osaka, Japan.
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10
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Usui K, Ichihashi N, Kazuta Y, Matsuura T, Yomo T. Kinetic model of double-stranded RNA formation during long RNA replication by Qβ replicase. FEBS Lett 2013; 587:2565-71. [DOI: 10.1016/j.febslet.2013.06.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 05/29/2013] [Accepted: 06/25/2013] [Indexed: 11/28/2022]
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11
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Ribosomal protein S1 functions as a termination factor in RNA synthesis by Qβ phage replicase. Nat Commun 2013; 4:1781. [DOI: 10.1038/ncomms2807] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 03/26/2013] [Indexed: 11/08/2022] Open
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12
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Ichihashi N, Matsuura T, Hosoda K, Yomo T. Identification of two forms of Q{beta} replicase with different thermal stabilities but identical RNA replication activity. J Biol Chem 2010; 285:37210-7. [PMID: 20858892 DOI: 10.1074/jbc.m110.117846] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The enzyme Qβ replicase is an RNA-dependent RNA polymerase, which plays a central role in infection by the simple single-stranded RNA virus bacteriophage Qβ. This enzyme has been used in a number of applications because of its unique activity in amplifying RNA from an RNA template. Determination of the thermal stability of Qβ replicase is important to gain an understanding of its function and potential applications, but data reported to date have been contradictory. Here, we provide evidence that these previous inconsistencies were due to the heterogeneous forms of the replicase with different stabilities. We purified two forms of replicase expressed in Escherichia coli, which differed in their thermal stability but showed identical RNA replication activity. Furthermore, we found that the replicase undergoes conversion between these forms due to oxidation, and the Cys-533 residue in the catalytic β subunit and Cys-82 residue in the EF-Tu subunit of the replicase are essential prerequisites for this conversion to occur. These results strongly suggest that the thermal stable replicase contains the intersubunit disulfide bond between these cysteines. The established strategies for isolating and purifying a thermally stable replicase should increase the usefulness of Qβ replicase in various applications, and the data regarding thermal stability obtained in this study may yield insight into the precise mechanism of infection by bacteriophage Qβ.
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Affiliation(s)
- Norikazu Ichihashi
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, Yamadaoka 1-5, Suita, Osaka 565-0871, Japan
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13
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Urabe H, Ichihashi N, Matsuura T, Hosoda K, Kazuta Y, Kita H, Yomo T. Compartmentalization in a Water-in-Oil Emulsion Repressed the Spontaneous Amplification of RNA by Qβ Replicase. Biochemistry 2010; 49:1809-13. [PMID: 20108973 DOI: 10.1021/bi901805u] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hiroya Urabe
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University
| | - Norikazu Ichihashi
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University
| | - Tomoaki Matsuura
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University
| | - Kazufumi Hosoda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University
| | - Yasuaki Kazuta
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University
| | - Hiroshi Kita
- Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Agency (JST)
| | - Tetsuya Yomo
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University
- Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Agency (JST)
- Graduate School of Frontier Biosciences, Osaka University
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14
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Ichihashi N, Matsuura T, Kita H, Hosoda K, Sunami T, Tsukada K, Yomo T. Importance of translation-replication balance for efficient replication by the self-encoded replicase. Chembiochem 2009; 9:3023-8. [PMID: 19021140 DOI: 10.1002/cbic.200800518] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In all living systems, the genetic information is replicated by the self-encoded replicase (Rep); this can be said to be a self-encoding system. Recently, we constructed a self-encoding system in liposomes as an artificial cell model, consisting of a reconstituted translation system and an RNA encoding the catalytic subunit of Qbeta Rep and the RNA was replicated by the self-encoded Rep produced by the translation reaction. In this system, both the ribosome (Rib) and Rep bind to the same RNA for translation and replication, respectively. Thus, there could be a dilemma: effective RNA replication requires high levels of Rep translation, but excessive translation in turn inhibits replication. Herein, we actually observed the competition between the Rib and Rep, and evaluated the effect for RNA replication by constructing a kinetic model that quantitatively explained the behavior of the self-encoding system. Both the experimental and theoretical results consistently indicated that the balance between translation and replication is critical for an efficient self-encoded system, and we determined the optimum balance.
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Affiliation(s)
- Norikazu Ichihashi
- Department of Bioinformatics Engineering, Graduate School of Information Science and Technology, Osaka University, Suita, Osaka, Japan
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15
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Chetverina HV, Chetverin AB. Nanocolonies: Detection, cloning, and analysis of individual molecules. BIOCHEMISTRY (MOSCOW) 2009; 73:1361-87. [DOI: 10.1134/s0006297908130014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Chetverin AB, Chetverina HV. Molecular Colony Technique: A New Tool for Biomedical Research and Clinical Practice. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2008; 82:219-55. [DOI: 10.1016/s0079-6603(08)00007-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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17
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Yakhnin AV. A model for the origin of protein synthesis as coreplicational scanning of nascent RNA. ORIGINS LIFE EVOL B 2007; 37:523-36. [PMID: 17882534 DOI: 10.1007/s11084-007-9108-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2006] [Accepted: 05/15/2007] [Indexed: 10/22/2022]
Abstract
The origin of protein synthesis is one of the major riddles of molecular biology. It was proposed a decade ago that the ribosomal RNA evolved from an earlier RNA-replisome (a ribozyme fulfilling RNA replication) while transfer RNA (tRNA) evolved from a genomic replication origin. Applying these hypotheses, I suggest that protein synthesis arose for the purpose of segregating copy and template RNA during replication through the conventional formation of a complementary strand. Nascent RNA was scanned in 5' to 3' direction following the progress of replication. The base pairing of several tRNA-like molecules with nascent RNA released the replication intermediates trapped in duplex. Synthesis of random peptides evolved to fuel the turnover of tRNAs. Then the combination of replication-coupled peptide formation and the independent development of amino acid-specific tRNA aminoacylation resulted in template-based protein synthesis. Therefore, the positioning of tRNAs adjacent to each other developed for the purpose of replication rather than peptide synthesis. This hypothesis does not include either selection for useful peptides or specific recognition of amino acids at the initial evolution of translation. It does, however, explain a number of features of modern translation apparatus, such as the relative flexibility of genetic code, the number of proteins shared by the transcription and translation machines, the universal participation of an RNA subunit in co-translational protein secretion, 'unscheduled translation', and factor-independent translocation. Assistance of original ribosomes in keeping apart the nascent transcript from its template is still widely explored by modern bacteria and perhaps by other domains of life.
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Affiliation(s)
- Alexander V Yakhnin
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA.
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18
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Kopsidas G, Carman RK, Stutt EL, Raicevic A, Roberts AS, Siomos MAV, Dobric N, Pontes-Braz L, Coia G. RNA mutagenesis yields highly diverse mRNA libraries for in vitro protein evolution. BMC Biotechnol 2007; 7:18. [PMID: 17425805 PMCID: PMC1855321 DOI: 10.1186/1472-6750-7-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Accepted: 04/11/2007] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND In protein drug development, in vitro molecular optimization or protein maturation can be used to modify protein properties. One basic approach to protein maturation is the introduction of random DNA mutations into the target gene sequence to produce a library of variants that can be screened for the preferred protein properties. Unfortunately, the capability of this approach has been restricted by deficiencies in the methods currently available for random DNA mutagenesis and library generation. Current DNA based methodologies generally suffer from nucleotide substitution bias that preferentially mutate particular base pairs or show significant bias with respect to transitions or transversions. In this report, we describe a novel RNA-based random mutagenesis strategy that utilizes Qbeta replicase to manufacture complex mRNA libraries with a mutational spectrum that is close to the ideal. RESULTS We show that Qbeta replicase generates all possible base substitutions with an equivalent preference for mutating A/T or G/C bases and with no significant bias for transitions over transversions. To demonstrate the high diversity that can be sampled from a Qbeta replicase-generated mRNA library, the approach was used to evolve the binding affinity of a single domain VNAR shark antibody fragment (12Y-2) against malarial apical membrane antigen-1 (AMA-1) via ribosome display. The binding constant (KD) of 12Y-2 was increased by 22-fold following two consecutive but discrete rounds of mutagenesis and selection. The mutagenesis method was also used to alter the substrate specificity of beta-lactamase which does not significantly hydrolyse the antibiotic cefotaxime. Two cycles of RNA mutagenesis and selection on increasing concentrations of cefotaxime resulted in mutants with a minimum 10,000-fold increase in resistance, an outcome achieved faster and with fewer overall mutations than in comparable studies using other mutagenesis strategies. CONCLUSION The RNA based approach outlined here is rapid and simple to perform and generates large, highly diverse populations of proteins, each differing by only one or two amino acids from the parent protein. The practical implications of our results are that suitable improved protein candidates can be recovered from in vitro protein evolution approaches using significantly fewer rounds of mutagenesis and selection, and with little or no collateral damage to the protein or its mRNA.
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Affiliation(s)
- George Kopsidas
- EvoGenix Ltd., 343 Royal Parade, Parkville, Melbourne 3052, Australia
| | - Rachael K Carman
- EvoGenix Ltd., 343 Royal Parade, Parkville, Melbourne 3052, Australia
| | - Emma L Stutt
- EvoGenix Ltd., 343 Royal Parade, Parkville, Melbourne 3052, Australia
| | - Anna Raicevic
- CSIRO, Molecular and Health Technologies, 343 Royal Parade, Parkville, Melbourne 3052, Australia
| | - Anthony S Roberts
- EvoGenix Ltd., 343 Royal Parade, Parkville, Melbourne 3052, Australia
| | | | - Nada Dobric
- EvoGenix Ltd., 343 Royal Parade, Parkville, Melbourne 3052, Australia
| | - Luisa Pontes-Braz
- CSIRO, Molecular and Health Technologies, 343 Royal Parade, Parkville, Melbourne 3052, Australia
| | - Greg Coia
- CSIRO, Molecular and Health Technologies, 343 Royal Parade, Parkville, Melbourne 3052, Australia
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Hosoda K, Matsuura T, Kita H, Ichihashi N, Tsukada K, Yomo T. Kinetic analysis of the entire RNA amplification process by Qbeta replicase. J Biol Chem 2007; 282:15516-27. [PMID: 17412690 DOI: 10.1074/jbc.m700307200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The kinetics of the RNA replication reaction by Qbeta replicase were investigated. Qbeta replicase is an RNA-dependent RNA polymerase responsible for replicating the RNA genome of coliphage Qbeta and plays a key role in the life cycle of the Qbeta phage. Although the RNA replication reaction using this enzyme has long been studied, a kinetic model that can describe the entire RNA amplification process has yet to be determined. In this study, we propose a kinetic model that is able to account for the entire RNA amplification process. The key to our proposed kinetic model is the consideration of nonproductive binding (i.e. binding of an enzyme to the RNA where the enzyme cannot initiate the reaction). By considering nonproductive binding and the notable enzyme inactivation we observed, the previous observations that remained unresolved could also be explained. Moreover, based on the kinetic model and the experimental results, we determined rate and equilibrium constants using template RNAs of various lengths. The proposed model and the obtained constants provide important information both for understanding the basis of Qbeta phage amplification and the applications using Qbeta replicase.
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Affiliation(s)
- Kazufumi Hosoda
- Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan
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20
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Kita H, Cho J, Matsuura T, Nakaishi T, Taniguchi I, Ichikawa T, Shima Y, Urabe I, Yomo T. Functional Qbeta replicase genetically fusing essential subunits EF-Ts and EF-Tu with beta-subunit. J Biosci Bioeng 2006; 101:421-6. [PMID: 16781472 DOI: 10.1263/jbb.101.421] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2005] [Accepted: 02/15/2006] [Indexed: 11/17/2022]
Abstract
Qbeta replicase, an RNA-dependent RNA polymerase of RNA coliphage Qbeta, is a heterotetramer composed of a phage-encoded beta-subunit and three host-encoded proteins: the ribosomal protein S1 (alpha-subunit), EF-Tu, and EF-Ts. Several purification methods for Qbeta replicase were described previously. However, in our efforts to improve the production of Qbeta replicase, a substantial amount of the beta-subunit overproduced in Escherichia coli cells was found as insoluble aggregates. In this paper, we describe two kinds of method of producing Qbeta replicase. In one kind, both EF-Tu and EF-Ts subunits were expressed with the beta-subunit, and in the other kind, the beta-subunit was genetically fused with EF-Tu and EF-Ts. The fused protein, a single-chain alpha-less Qbeta replicase, was mostly found in the soluble fraction and could be readily purified. These results pave the way for the large-scale production of the highly purified form of this enzyme.
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Affiliation(s)
- Hiroshi Kita
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Japan
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21
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Chetverin AB, Kopein DS, Chetverina HV, Demidenko AA, Ugarov VI. Viral RNA-directed RNA polymerases use diverse mechanisms to promote recombination between RNA molecules. J Biol Chem 2004; 280:8748-55. [PMID: 15611043 DOI: 10.1074/jbc.m412684200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
An earlier developed purified cell-free system was used to explore the potential of two RNA-directed RNA polymerases (RdRps), Qbeta phage replicase and the poliovirus 3Dpol protein, to promote RNA recombination through a primer extension mechanism. The substrates of recombination were fragments of complementary strands of a Qbeta phage-derived RNA, such that if aligned at complementary 3'-termini and extended using one another as a template, they would produce replicable molecules detectable as RNA colonies grown in a Qbeta replicase-containing agarose. The results show that while 3Dpol efficiently extends the aligned fragments to produce the expected homologous recombinant sequences, only nonhomologous recombinants are generated by Qbeta replicase at a much lower yield and through a mechanism not involving the extension of RNA primers. It follows that the mechanisms of RNA recombination by poliovirus and Qbeta RdRps are quite different. The data favor an RNA transesterification reaction catalyzed by a conformation acquired by Qbeta replicase during RNA synthesis and provide a likely explanation for the very low frequency of homologous recombination in Qbeta phage.
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Affiliation(s)
- Alexander B Chetverin
- Institute of Protein Research of the Russian Academy of Sciences, Pushchino, Moscow Region, 142290 Russia.
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22
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Abstract
This paper summarizes results of the 40-year studies on replication and recombination of RNA molecules in the cell-free amplification system of bacteriophage Q. Special attention is paid to the molecular colony technique that has provided for the discovery of the nature of "spontaneous" RNA synthesis by Q replicase and of the ability of RNA molecules to spontaneously rearrange their sequences under physiological conditions. Also discussed is the impact of these data on the concept of RNA World and on the development of new in vitro cloning and diagnostic tools.
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Affiliation(s)
- Alexander B Chetverin
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow, Russia.
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23
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Ugarov VI, Demidenko AA, Chetverin AB. Qbeta replicase discriminates between legitimate and illegitimate templates by having different mechanisms of initiation. J Biol Chem 2003; 278:44139-46. [PMID: 12947121 DOI: 10.1074/jbc.m305992200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Qbeta replicase (RNA-directed RNA polymerase of bacteriophage Qbeta) exponentially amplifies certain RNAs (RQ RNAs) in vitro. Here we characterize template properties of the 5' and 3' fragments obtained by cleaving one of such RNAs at an internal site. We unexpectedly found that, besides the 3' fragment, Qbeta replicase can copy the 5' fragment and a number of its variants, although they lack the initiator region of RQ RNA. This copying can occur as a 3'-terminal elongation or through de novo initiation. In contradistinction to RQ RNA and its 3' fragment, initiation on these templates occurs without regard to the 3'-terminal or internal oligo(C) clusters, is GTP-independent, and does not result in a stable replicative complex capable of elongation in the presence of aurintricarboxylic acid. The results suggest that, although Qbeta replicase can initiate and elongate on a variety of RNAs, only some of them are recognized as legitimate templates. GTP-dependent initiation on a legitimate template drives the enzyme to a "closed" conformation that may be important for keeping the template and the complementary nascent strand unannealed, without which the exponential replication is impossible. Triggering the GTP-dependent conformational transition at the initiation step could serve as a discriminative feature of legitimate templates providing for the high template specificity of Qbeta replicase.
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Affiliation(s)
- Victor I Ugarov
- Institute of Protein Research of the Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
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24
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Nakaishi T, Iio K, Yamamoto K, Urabe I, Yomo T. Kinetic properties of Qβ replicase, an RNA dependent RNA polymerase. J Biosci Bioeng 2002. [DOI: 10.1016/s1389-1723(02)80036-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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25
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FUKANO HAJIME, ZAKO TAMOTSU, SUZUKI EIJI, WATANABE KIMITSUNA, NAGAMUNE TERUYUKI. Genetically Engineered Active Q.BETA. Replicase in Rabbit Reticulocyte Cell-Free System: A Fusion Protein of EF-Tu and EF-Ts Is Functional as the Subunit of Q.BETA. Replicase. J Biosci Bioeng 2002. [DOI: 10.1263/jbb.93.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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Fukano H, Tamotsu Z, Eiji S, Kimitsuna W, Teruyuki N. Genetically engineered active Qβ replicase in rabbit reticulocyte cell-free system: a fusion protein of EF-Tu and EF-Ts is functional as the subunit of Qβ replicase. J Biosci Bioeng 2002; 93:20-4. [PMID: 16233159 DOI: 10.1016/s1389-1723(02)80048-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2001] [Accepted: 10/15/2001] [Indexed: 11/16/2022]
Abstract
Qbeta replicase functioning in Escherichia coli is an RNA-dependent RNA polymerase composed of one phage-coded subunit and three host-coded proteins: ribosomal protein S1, and protein elongation factors EF-Tu and EF-Ts. Qbeta replicase lacking ribosomal protein S1 (alpha-less replicase) is capable of replicating some small RNAs. We attempted to create functional alpha-less replicase by co-expression of the mRNAs that code for the subunits of alpha-less replicase in a rabbit reticulocyte cell-free translation system. Replicase activity, however, could not be detected when both EF-Tu and EF-Ts were co-expressed with the phage-coded subunit. On the other hand, active alpha-less replicase was obtained when an EF-Ts-EF-Tu fusion protein was co-expressed with the phage-coded subunit. Consequently, we succeeded in generating genetically engineered active alpha-less Qbeta replicase which functions in a eukaryotic cell-free system.
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Affiliation(s)
- Hajime Fukano
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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27
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Coia G, Pontes-Braz L, Nuttall SD, Hudson PJ, Irving RA. Panning and selection of proteins using ribosome display. J Immunol Methods 2001; 254:191-7. [PMID: 11406164 DOI: 10.1016/s0022-1759(01)00409-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Eukaryotic ribosome complexes can be used as a means to display a library of proteins, and isolate specific binding reagents by screening against target molecules. Here we present, as an example, a method for the display of a library of immunoglobulin variable-like domains (VLDs) for the production of stable mRNA/ribosome/protein complexes. These complexes are produced by the addition of specific in vitro transcriptional promoter elements and translation control sequences to the template DNA. Furthermore, an appropriate spacer (anchor) domain is included for efficient folding of the nascent translated protein, which remains attached to the ribosome complex. Ribosome complexes are panned against hen egg lysozyme-conjugated magnetic beads and genes encoding specific, binding, V-like domains are recovered by RT-PCR and cloned into an Escherichia coli expression vector.
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Affiliation(s)
- G Coia
- CRC for Diagnostic Technologies, CSIRO Health Sciences and Nutrition, 343 Royal Parade, Parkville, Victoria 3052, Australia.
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28
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29
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Abstract
The ability of RNAs to spontaneously rearrange their sequences under physiological conditions is demonstrated using the molecular colony technique, which allows single RNA molecules to be detected provided that they are amplifiable by the replicase of bacteriophage Qbeta. The rearrangements are Mg2+-dependent, sequence-non-specific, and occur both in trans and in cis at a rate of 10(-9) h(-1) per site. The results suggest that the mechanism of spontaneous RNA rearrangements differs from the transesterification reactions earlier observed in the presence of Qbeta replicase, and have a number of biologically important implications.
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Affiliation(s)
- H V Chetverina
- Institute of Protein Research, Russian Academy of Sciences, Moscow Region
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30
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Chetverin AB, Chetverina HV, Demidenko AA, Ugarov VI. Nonhomologous RNA recombination in a cell-free system: evidence for a transesterification mechanism guided by secondary structure. Cell 1997; 88:503-13. [PMID: 9038341 PMCID: PMC7173214 DOI: 10.1016/s0092-8674(00)81890-5] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Extensive nonhomologous recombinations occur between the 5' and 3' fragments of a replicable RNA in a cell-free system composed of pure Qbeta phage replicase and ribonucleoside triphosphates, providing direct evidence for the ability of RNAs to recombine without DNA intermediates and in the absence of host cell proteins. The recombination events are revealed by the molecular colony technique that allows single RNA molecules to be cloned in vitro. The observed nonhomologous recombinations are entirely dependent on the 3' hydroxyl group of the 5' fragment, and are due to a splicing-like reaction in which RNA secondary structure guides the attack of this 3' hydroxyl on phosphoester bonds within the 3' fragment.
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Affiliation(s)
- Alexander B Chetverin
- Institute of Protein Research, Russian Academy of Sciences, 142292 Pushchino, Moscow Region, Russia
- Correspondence: Alexander B. Chetverin, 00 795 924 0493 (phone), 00 795 924 0493 (fax)
| | - Helena V Chetverina
- Institute of Protein Research, Russian Academy of Sciences, 142292 Pushchino, Moscow Region, Russia
| | - Alexander A Demidenko
- Institute of Protein Research, Russian Academy of Sciences, 142292 Pushchino, Moscow Region, Russia
| | - Victor I Ugarov
- Institute of Protein Research, Russian Academy of Sciences, 142292 Pushchino, Moscow Region, Russia
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31
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Chetverin AB, Spirin AS. Replicable RNA vectors: prospects for cell-free gene amplification, expression, and cloning. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1995; 51:225-70. [PMID: 7544901 DOI: 10.1016/s0079-6603(08)60880-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- A B Chetverin
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region
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32
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Ugarov VI, Jung GY, Chetverin AB, Spirin AS. Expression and stability of recombinant RQ-mRNAs in cell-free translation systems. FEBS Lett 1994; 341:131-4. [PMID: 8137913 DOI: 10.1016/0014-5793(94)80255-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Expression of dihydrofolate reductase (DHFR) and chloramphenicol acetyltransferase (CAT) mRNAs in cell-free Escherichia coli translation systems is greatly enhanced as a result of their insertion into RQ135 RNA, a naturally occurring satellite of phage Q beta. The enhancement is due to protection of the recombinant mRNAs against endogenous ribonucleases and to an increased initial rate of translation in the case of the RQ-CAT mRNA.
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Affiliation(s)
- V I Ugarov
- Institute of Protein Research, Russian Academy of Sciences, Puschino, Moscow Region
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33
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Ryabova L, Volianik E, Kurnasov O, Spirin A, Wu Y, Kramer F. Coupled replication-translation of amplifiable messenger RNA. A cell-free protein synthesis system that mimics viral infection. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)42284-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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