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Yang N, Li R, Liu R, Yang S, Zhao Y, Xiong W, Qiu L. The Emerging Function and Promise of tRNA-Derived Small RNAs in Cancer. J Cancer 2024; 15:1642-1656. [PMID: 38370372 PMCID: PMC10869971 DOI: 10.7150/jca.89219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/01/2024] [Indexed: 02/20/2024] Open
Abstract
Fragments derived from tRNA, called tRNA-derived small RNAs (tsRNAs), have attracted widespread attention in the past decade. tsRNAs are widespread in prokaryotic and eukaryotic transcriptome, which contains two main types, tRNA-derived fragments (tRFs) and tRNA-derived stress-inducing RNA (tiRNAs), derived from the precursor tRNAs or mature tRNAs. According to differences in the cleavage position, tRFs can be divided into tRF-1, tRF-2, tRF-3, tRF-5, and i-tRF, whereas tiRNAs can be divided into 5'-tiRNA and 3'-tiRNA. Studies have found that tRFs and tiRNAs are abnormally expressed in a variety of human malignant tumors, promote or inhibit the proliferation and apoptosis of cancer cells by regulating the expression of oncogene, and play an important role in the aggressive metastasis and progression of tumors. This article reviews the biological origins of various tsRNAs, introduces their functions and new concepts of related mechanisms, and focuses on the molecular mechanisms of tsRNAs in cancer, including breast cancer, prostate cancer, colorectal cancer, lung cancer, b-cell lymphoma, and chronic lymphoma cell leukemia. Lastly, this article puts forward some unresolved problems and future research prospects.
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Affiliation(s)
- Na Yang
- College of Resources, Environment and Chemistry, Chuxiong Normal University, Chuxiong 675000, China
- College of Basic Medical Sciences, Dali University, Dali 671000, China
| | - Ruijun Li
- College of Foreign Languages, Chuxiong Normal University, Chuxiong 675000, China
| | - Ruai Liu
- College of Basic Medical Sciences, Dali University, Dali 671000, China
| | - Shengjie Yang
- The People's Hospital of ChuXiong Yi Autonomous Prefecture, Chuxiong 675000, China
| | - Yi Zhao
- The People's Hospital of ChuXiong Yi Autonomous Prefecture, Chuxiong 675000, China
| | - Wei Xiong
- College of Basic Medical Sciences, Dali University, Dali 671000, China
| | - Lu Qiu
- College of Resources, Environment and Chemistry, Chuxiong Normal University, Chuxiong 675000, China
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Di Fazio A, Gullerova M. An old friend with a new face: tRNA-derived small RNAs with big regulatory potential in cancer biology. Br J Cancer 2023; 128:1625-1635. [PMID: 36759729 PMCID: PMC10133234 DOI: 10.1038/s41416-023-02191-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 01/24/2023] [Accepted: 01/26/2023] [Indexed: 02/11/2023] Open
Abstract
Transfer RNAs (tRNAs) are small non-coding RNAs (sncRNAs) essential for protein translation. Emerging evidence suggests that tRNAs can also be processed into smaller fragments, tRNA-derived small RNAs (tsRNAs), a novel class of sncRNAs with powerful applications and high biological relevance to cancer. tsRNAs biogenesis is heterogeneous and involves different ribonucleases, such as Angiogenin and Dicer. For many years, tsRNAs were thought to be just degradation products. However, accumulating evidence shows their roles in gene expression: either directly via destabilising the mRNA or the ribosomal machinery, or indirectly via regulating the expression of ribosomal components. Furthermore, tsRNAs participate in various biological processes linked to cancer, including apoptosis, cell cycle, immune response, and retroviral insertion into the human genome. It is emerging that tsRNAs have significant therapeutic potential. Endogenous tsRNAs can be used as cancer biomarkers, while synthetic tsRNAs and antisense oligonucleotides can be employed to regulate gene expression. In this review, we are recapitulating the regulatory roles of tsRNAs, with a focus on cancer biology.
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Affiliation(s)
- Arianna Di Fazio
- Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK
| | - Monika Gullerova
- Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK.
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3
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Tian H, Hu Z, Wang C. The Therapeutic Potential of tRNA-derived Small RNAs in Neurodegenerative Disorders. Aging Dis 2022; 13:389-401. [PMID: 35371602 PMCID: PMC8947841 DOI: 10.14336/ad.2021.0903] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/02/2021] [Indexed: 11/01/2022] Open
Abstract
Gene expressions and functions at various levels, namely post-transcriptional, transcriptional, and epigenetic, can be regulated by transfer RNA (tRNA)-derived small RNAs (tsRNAs), which are as well-established as tRNA fragments or tRFs. This regulation occurs when tsRNAs are created through the special endonuclease-mediated cleavage of mature or precursor tRNAs. However, tsRNAs are newly discovered entities, and molecular functions associated with tsRNAs are still not clearly understood. There is increasingly robust evidence suggesting that specific tsRNAs perform fundamental tasks in the pathogenesis of neurodevelopmental, neurodegenerative, and neurobehavioral disorders. Indeed, the patterns of tsRNA expression are uncertain and could be altered in patients suffering from Parkinson's disease, pontocerebellar hypoplasia, amyotrophic lateral sclerosis, Alzheimer's disease, and other neurodegenerative disorders. In the present article, a review is conducted of recent domestic and international progress in research on the potential cellular and molecular mechanisms of tsRNA biogenesis. We also describe endogenous tsRNAs during neuronal development and neurodegenerative disorders, thereby providing theoretical support and guidance for further revealing the therapeutic potential of tsRNAs in neurodegenerative disorders.
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Affiliation(s)
- Haihua Tian
- 1Ningbo Key Laboratory of Behavioral Neuroscience, Ningbo University School of Medicine, Ningbo, Zhejiang, China.,2Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang, China.,3Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo, Zhejiang, China.,4Department of Laboratory Medicine, Ningbo Kangning Hospital, Ningbo, Zhejiang, China
| | - Zhenyu Hu
- 5Department of Child Psychiatry, Ningbo Kanning Hospital, Ningbo, Zhejiang, China
| | - Chuang Wang
- 1Ningbo Key Laboratory of Behavioral Neuroscience, Ningbo University School of Medicine, Ningbo, Zhejiang, China.,2Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, Zhejiang, China.,3Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo, Zhejiang, China
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Chen Q, Zhang X, Shi J, Yan M, Zhou T. Origins and evolving functionalities of tRNA-derived small RNAs. Trends Biochem Sci 2021; 46:790-804. [PMID: 34053843 PMCID: PMC8448906 DOI: 10.1016/j.tibs.2021.05.001] [Citation(s) in RCA: 83] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 04/22/2021] [Accepted: 05/03/2021] [Indexed: 12/14/2022]
Abstract
Transfer RNA (tRNA)-derived small RNAs (tsRNAs) are among the most ancient small RNAs in all domains of life and are generated by the cleavage of tRNAs. Emerging studies have begun to reveal the versatile roles of tsRNAs in fundamental biological processes, including gene silencing, ribosome biogenesis, retrotransposition, and epigenetic inheritance, which are rooted in tsRNA sequence conservation, RNA modifications, and protein-binding abilities. We summarize the mechanisms of tsRNA biogenesis and the impact of RNA modifications, and propose how thinking of tsRNA functionality from an evolutionary perspective urges the expansion of tsRNA research into a wider spectrum, including cross-tissue/cross-species regulation and harnessing of the 'tsRNA code' for precision medicine.
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Affiliation(s)
- Qi Chen
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, CA, USA.
| | - Xudong Zhang
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, CA, USA
| | - Junchao Shi
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, CA, USA
| | - Menghong Yan
- Institutes of Biomedical Sciences, Shanghai Medical College of Fudan University, Shanghai, China; Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, USA
| | - Tong Zhou
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, USA.
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Park J, Ahn SH, Shin MG, Kim HK, Chang S. tRNA-Derived Small RNAs: Novel Epigenetic Regulators. Cancers (Basel) 2020; 12:cancers12102773. [PMID: 32992597 PMCID: PMC7599909 DOI: 10.3390/cancers12102773] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 09/24/2020] [Accepted: 09/24/2020] [Indexed: 12/17/2022] Open
Abstract
Simple Summary Cells must synthesize new proteins to maintain its life and tRNA (transfer RNA) is an essential component of the translation process. tRNA-derived small RNA (tsRNA) is a relatively uncharacterized small RNA, derived from enzymatic cleavage of the tRNAs. Accumulating evidences suggest that tsRNA is an abundant, highly modified, dynamically regulated small-RNA and interacts with other types of RNAs or proteins. Moreover, it is abnormally expressed in multiple human diseases including systemic lupus, neurological disorder, metabolic disorder and cancer, implying its diverse function in the initiation or progression of such diseases. In this review, we summarize the classification of tsRNA and its role focused on the epigenetic regulation. Further, we discuss the limitation of current knowledge about the tsRNA and its potential applications. Abstract An epigenetic change is a heritable genetic alteration that does not involve any nucleotide changes. While the methylation of specific DNA regions such as CpG islands or histone modifications, including acetylation or methylation, have been investigated in detail, the role of small RNAs in epigenetic regulation is largely unknown. Among the many types of small RNAs, tRNA-derived small RNAs (tsRNAs) represent a class of noncoding small RNAs with multiple roles in diverse physiological processes, including neovascularization, sperm maturation, immune modulation, and stress response. Regarding these roles, several pioneering studies have revealed that dysregulated tsRNAs are associated with human diseases, such as systemic lupus, neurological disorder, metabolic disorder, and cancer. Moreover, recent findings suggest that tsRNAs regulate the expression of critical genes linked with these diseases by a variety of mechanisms, including epigenetic regulation. In this review, we will describe different classes of tsRNAs based on their biogenesis and will focus on their role in epigenetic regulation.
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Affiliation(s)
- Joonhyeong Park
- Department of Life Science, Chung-Ang University, Seoul 06974, Korea; (J.P.); (M.G.S.)
| | - Se Hee Ahn
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea;
| | - Myung Geun Shin
- Department of Life Science, Chung-Ang University, Seoul 06974, Korea; (J.P.); (M.G.S.)
| | - Hak Kyun Kim
- Department of Life Science, Chung-Ang University, Seoul 06974, Korea; (J.P.); (M.G.S.)
- Correspondence: (H.K.K.); (S.C.); Tel.: +82-2-820-5197 (H.K.K.); +82-2-3010-2095 (S.C.)
| | - Suhwan Chang
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea;
- Department of Physiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea
- Correspondence: (H.K.K.); (S.C.); Tel.: +82-2-820-5197 (H.K.K.); +82-2-3010-2095 (S.C.)
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Kawaji H, Nakamura M, Takahashi Y, Sandelin A, Katayama S, Fukuda S, Daub CO, Kai C, Kawai J, Yasuda J, Carninci P, Hayashizaki Y. Hidden layers of human small RNAs. BMC Genomics 2008. [PMID: 18402656 DOI: 10.1186/1471-12164-9-157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/15/2023] Open
Abstract
BACKGROUND Small RNA attracts increasing interest based on the discovery of RNA silencing and the rapid progress of our understanding of these phenomena. Although recent studies suggest the possible existence of yet undiscovered types of small RNAs in higher organisms, many studies to profile small RNA have focused on miRNA and/or siRNA rather than on the exploration of additional classes of RNAs. RESULTS Here, we explored human small RNAs by unbiased sequencing of RNAs with sizes of 19-40 nt. We provide substantial evidences for the existence of independent classes of small RNAs. Our data shows that well-characterized non-coding RNA, such as tRNA, snoRNA, and snRNA are cleaved at sites specific to the class of ncRNA. In particular, tRNA cleavage is regulated depending on tRNA type and tissue expression. We also found small RNAs mapped to genomic regions that are transcribed in both directions by bidirectional promoters, indicating that the small RNAs are a product of dsRNA formation and their subsequent cleavage. Their partial similarity with ribosomal RNAs (rRNAs) suggests unrevealed functions of ribosomal DNA or interstitial rRNA. Further examination revealed six novel miRNAs. CONCLUSION Our results underscore the complexity of the small RNA world and the biogenesis of small RNAs.
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Affiliation(s)
- Hideya Kawaji
- Genome Science Laboratory, Discovery and Research Institute, RIKEN Wako Main Campus, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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Kawaji H, Nakamura M, Takahashi Y, Sandelin A, Katayama S, Fukuda S, Daub CO, Kai C, Kawai J, Yasuda J, Carninci P, Hayashizaki Y. Hidden layers of human small RNAs. BMC Genomics 2008; 9:157. [PMID: 18402656 PMCID: PMC2359750 DOI: 10.1186/1471-2164-9-157] [Citation(s) in RCA: 232] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Accepted: 04/10/2008] [Indexed: 01/09/2023] Open
Abstract
Background Small RNA attracts increasing interest based on the discovery of RNA silencing and the rapid progress of our understanding of these phenomena. Although recent studies suggest the possible existence of yet undiscovered types of small RNAs in higher organisms, many studies to profile small RNA have focused on miRNA and/or siRNA rather than on the exploration of additional classes of RNAs. Results Here, we explored human small RNAs by unbiased sequencing of RNAs with sizes of 19–40 nt. We provide substantial evidences for the existence of independent classes of small RNAs. Our data shows that well-characterized non-coding RNA, such as tRNA, snoRNA, and snRNA are cleaved at sites specific to the class of ncRNA. In particular, tRNA cleavage is regulated depending on tRNA type and tissue expression. We also found small RNAs mapped to genomic regions that are transcribed in both directions by bidirectional promoters, indicating that the small RNAs are a product of dsRNA formation and their subsequent cleavage. Their partial similarity with ribosomal RNAs (rRNAs) suggests unrevealed functions of ribosomal DNA or interstitial rRNA. Further examination revealed six novel miRNAs. Conclusion Our results underscore the complexity of the small RNA world and the biogenesis of small RNAs.
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Affiliation(s)
- Hideya Kawaji
- Genome Science Laboratory, Discovery and Research Institute, RIKEN Wako Main Campus, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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8
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Hori Y, Rogert MC, Tanaka T, Kikuchi Y, Bichenkova EV, Wilton AN, Gbaj A, Douglas KT. Porphyrins and porphines bind strongly and specifically to tRNA, precursor tRNA and to M1 RNA and inhibit the ribonuclease P ribozyme reaction. ACTA ACUST UNITED AC 2005; 1730:47-55. [PMID: 16005529 DOI: 10.1016/j.bbaexp.2005.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Revised: 06/01/2005] [Accepted: 06/06/2005] [Indexed: 10/25/2022]
Abstract
Porphyrins and porphines strongly inhibit the action of the RNA subunit of the Escherichia coli ribonuclease P (M1 RNA). Meso-tetrakis(N-methyl-pyridyl)porphine followed linear competitive kinetics with pre-tRNA(Gly1) from E. coli as variable substrate (Ki 0.960 microM). Protoporphyrin IX showed linear competitive inhibition versus pre-tRNA(Gly1) from E. coli (Ki 1.90 microM). Inhibition by meso-tetrakis[4-(trimethylammonio)phenyl]porphine versus pre-tRNA(Gly1) from E. coli followed non-competitive kinetics (Ki 4.1 microM). The porphyrins bound directly to E. coli tRNAVal, E. coli pre-tRNAGly1 and M1 RNA and dissociation constants for the 1:1 complexes were determined using fluorescence spectroscopy. Dissociation constants (microM) against E. coli tRNAVal and E. coli pre-tRNAGly were: meso-tetrakis(N-methyl-pyridyl)porphine 1.21 and 0.170; meso-tetrakis[4-(trimethylammonio)phenyl]porphine, 0.107 and 0.293; protoporphyrin IX, 0.138 and 0.0819. For M1 RNA, dissociation constants were 32.8 nM for meso-tetrakis(N-methyl-pyridyl)porphine and 59.8 nM for meso-tetrakis[4-(trimethylammonio)phenyl]porphine and excitation and emission spectra indicate a binding mode with strong pi-stacking of the porphine nucleus and base pairs in a rigid low-polarity environment. Part of the inhibition of ribonuclease P is from interaction with the pre-tRNA substrate, resulting from porphyrin binding to the D-loop/T-loop region which interfaces with M1 RNA during catalysis, and part from the porphyrin binding to the M1 RNA component.
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Affiliation(s)
- Yoshiaki Hori
- Division of Bioscience and Biotechnology, Department of Ecological Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi, 441-8580, Japan
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Tanaka T, Baba H, Hori Y, Kikuchi Y. Guide DNA technique reveals that the protein component of bacterial ribonuclease P is a modifier for substrate recognition. FEBS Lett 2001; 491:94-8. [PMID: 11226427 DOI: 10.1016/s0014-5793(01)02170-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We developed a guide DNA technique with which the cleavage efficiency of pre-tRNA substrate raised in the RNase P reaction. The 20-mer guide DNAs hybridizing to the upstream region of the cleaving site enhanced the cleavage reactions of RNA substrates by Escherichia coli RNase P. This guide DNA technique was also applicable to cleavage site selection by choosing the DNA-hybridizing site. Results showed that RNase P accepts DNA/RNA double-stranded 5'-leader region with high catalytic efficiency as well as single-stranded RNA region in pre-tRNAs as substrates, which suggests that the protein component of bacterial RNase P prefers bulky nucleotides. The protein component did not affect the normal 5'-processing reaction of pre-tRNAs, but enhanced the mis-cleaving (hyperprocessing) reactions of tRNA in non-cloverleaf folding. Our results suggested that the protein component of RNase P is a modifier for substrate recognition.
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Affiliation(s)
- T Tanaka
- Division of Bioscience and Biotechnology, Department of Ecological Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi, 441-8580, Aichi, Japan.
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10
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Hori Y, Baba H, Ueda R, Tanaka T, Kikuchi Y. In vitro hyperprocessing of Drosophila tRNAs by the catalytic RNA of RNase P the cloverleaf structure of tRNA is not always stable? EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:4781-8. [PMID: 10903512 DOI: 10.1046/j.1432-1327.2000.01534.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have previously reported that the catalytic RNA subunit of RNase P of Escherichia coli (M1 RNA) cleaves Drosophila initiator methionine tRNA (tRNA(Met)i) within the mature tRNA sequence to produce specific fragments. This cleavage was dependent on the occurrence of an altered conformation of the tRNA substrate. We call this further cleavage hyperprocessing. In the present paper, to search for another tRNA that can be hyperprocessed in vitro, we used total mature tRNAs from Drosophila as substrates for the in vitro M1 RNA reaction. We found that some tRNAs can be hyperprocessed by M1 RNA and that two such tRNAs are an alanine tRNA and a histidine tRNA. Using mutant substrates of these tRNAs, we also show that the hyperprocessing by M1 RNA is dependent on the occurrence of altered conformations of these tRNAs. The altered conformations were very similar to that of tRNA(Met)i. We show here that M1 RNA can be used as a powerful tool to detect the alternative conformation of tRNAs. The relationship between these hyperprocessing reactions and stability of the tRNA structure will also be discussed.
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Affiliation(s)
- Y Hori
- Division of Bioscience and Biotechnology, Department of Ecological Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi, Japan
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11
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Hori Y, Tanaka T, Kikuchi Y. The catalytic RNA of RNase P from Escherichia coli cleaves Drosophila 2S ribosomal RNA in vitro: a new type of naturally occurring substrate for the ribozyme. FEBS Lett 2000; 472:187-90. [PMID: 10788608 DOI: 10.1016/s0014-5793(00)01463-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have found that the catalytic RNA of RNase P of Escherichia coli (M1 RNA) can cleave 2S ribosomal RNA (2S rRNA) of Drosophila melanogaster at specific positions in vitro. The cleavage mainly occurred at two sites between nucleotides 11 and 12, and between 16 and 17 of 2S rRNA. Kinetic analyses of the reaction revealed that a dimer caused by intermolecular interaction of 2S rRNA may be the substrate for the cleavage between 11 and 12, while a simple monomer is the substrate for the cleavage between 16 and 17. Substrate recognition by M1 RNA is also discussed.
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Affiliation(s)
- Y Hori
- Division of Bioscience and Biotechnology, Department of Ecological Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi, Aichi, Japan
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12
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Ke N, Gao X, Keeney JB, Boeke JD, Voytas DF. The yeast retrotransposon Ty5 uses the anticodon stem-loop of the initiator methionine tRNA as a primer for reverse transcription. RNA (NEW YORK, N.Y.) 1999; 5:929-938. [PMID: 10411136 PMCID: PMC1369817 DOI: 10.1017/s1355838299990015] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Retrotransposons and retroviruses replicate by reverse transcription of an mRNA intermediate. Most retroelements initiate reverse transcription from a host-encoded tRNA primer. DNA synthesis typically extends from the 3'-OH of the acceptor stem, which is complementary to sequences on the retroelement mRNA (the primer binding site, PBS). However, for some retrotransposons, including the yeast Ty5 elements, sequences in the anticodon stem-loop of the initiator methionine tRNA (IMT) are complementary to the PBS. We took advantage of the genetic tractability of the yeast system to investigate the mechanism of Ty5 priming. We found that transposition frequencies decreased at least 800-fold for mutations in the Ty5 PBS that disrupt complementarity with the IMT. Similarly, transposition was reduced at least 200-fold for IMT mutations in the anticodon stem-loop. Base pairing between the Ty5 PBS and IMT is essential for transposition, as compensatory changes that restored base pairing between the two mutant RNAs restored transposition significantly. An analysis of 12 imt mutants with base changes outside of the region of complementarity failed to identify other tRNA residues important for transposition. In addition, assays carried out with heterologous IMTs from Schizosaccharomyces pombe and Arabidopsis thaliana indicated that residues outside of the anticodon stem-loop have at most a fivefold effect on transposition. Our genetic system should make it possible to further define the components required for priming and to understand the mechanism by which Ty5's novel primer is generated.
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Affiliation(s)
- N Ke
- Department of Zoology and Genetics, Iowa State University, Ames, 50011, USA
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13
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Chamberlain JR, Lee Y, Lane WS, Engelke DR. Purification and characterization of the nuclear RNase P holoenzyme complex reveals extensive subunit overlap with RNase MRP. Genes Dev 1998; 12:1678-90. [PMID: 9620854 PMCID: PMC316871 DOI: 10.1101/gad.12.11.1678] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/1998] [Accepted: 04/03/1998] [Indexed: 02/07/2023]
Abstract
Ribonuclease P (RNase P) is a ribonucleoprotein enzyme that cleaves precursor tRNA transcripts to give mature 5' ends. RNase P in eubacteria has a large, catalytic RNA subunit and a small protein subunit that are required for precursor tRNA cleavage in vivo. Although the eukaryotic holoenzymes have similar, large RNA subunits, previous work in a number of systems has suggested that the eukaryotic enzymes require a greater protein content. We have purified the Saccharomyces cerevisiae nuclear RNase P to apparent homogeneity, allowing the first comprehensive analysis of an unexpectedly complex subunit composition. Peptide sequencing by ion trap mass spectrometry identifies nine proteins that copurify with the nuclear RNase P RNA subunit, totaling 20-fold more protein than in the bacterial enzyme. All of these proteins are encoded by genes essential for RNase P activity and for cell viability. Previous genetic studies suggested that four proteins might be subunits of both RNase P and RNase MRP, the related rRNA processing enzyme. We demonstrate that all four of these proteins, Pop1p, Pop3p, Pop4p, and Rpp1p, are integral subunits of RNase P. In addition, four of the five newly identified protein subunits, Pop5p, Pop6p, Pop7p, and Pop8p, also appear to be shared between RNase P and RNase MRP. Only one polypeptide, Rpr2p, is unique to the RNase P holoenzyme by genetic depletion and immunoprecipitation studies. The large increase in the number of protein subunits over eubacterial RNase P is consistent with an increase in functional complexity in eukaryotes. The degree of structural similarity between nuclear RNase P and RNase MRP suggests that some aspects of their functions in pre-tRNA and pre-rRNA processing pathways might overlap or be coordinated.
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Affiliation(s)
- J R Chamberlain
- Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, Michigan 48109-0606 USA
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14
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Leng P, Klatte DH, Schumann G, Boeke JD, Steck TL. Skipper, an LTR retrotransposon of Dictyostelium. Nucleic Acids Res 1998; 26:2008-15. [PMID: 9518497 PMCID: PMC147500 DOI: 10.1093/nar/26.8.2008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The complete sequence of a retrotransposon from Dictyostelium discoideum , named skipper , was obtained from cDNA and genomic clones. The sequence of a nearly full-length skipper cDNA was similar to that of three other partially sequenced cDNAs. The corresponding retrotransposon is represented in approximately 15-20 copies and is abundantly transcribed. Skipper contains three open reading frames (ORFs) with an unusual sequence organization, aspects of which resemble certain mammalian retroviruses. ORFs 1 and 3 correspond to gag and pol genes; the second ORF, pro, corresponding to protease, was separated from gag by a single stop codon followed shortly thereafter by a potential pseudoknot. ORF3 (pol) was separated from pro by a +1 frameshift. ORFs 2 and 3 overlapped by 32 bp. The computed amino acid sequences of the skipper ORFs contain regions resembling retrotransposon polyprotein domains, including a nucleic acid binding protein, aspartyl protease, reverse transcriptase and integrase. Skipper is the first example of a retrotransposon with a separate pro gene. Skipper is also novel in that it appears to use stop codon suppression rather than frameshifting to modulate pro expression. Finally, skipper and its components may provide useful tools for the genetic characterization of Dictyostelium.
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Affiliation(s)
- P Leng
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
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15
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Matthews GD, Goodwin TJ, Butler MI, Berryman TA, Poulter RT. pCal, a highly unusual Ty1/copia retrotransposon from the pathogenic yeast Candida albicans. J Bacteriol 1997; 179:7118-28. [PMID: 9371461 PMCID: PMC179655 DOI: 10.1128/jb.179.22.7118-7128.1997] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Retrotransposons are mobile genetic elements. They can transpose via the reverse transcription of mRNA into double-stranded DNA (dsDNA) followed by the insertion of this dsDNA into new sites within the host genome. The unintegrated, linear, dsDNA form of retrotransposons is usually very rare. We report here the isolation of a retrotransposon from Candida albicans which is unusual in this respect. This element, which we have named pCal, was first identified as a distinct band when uncut C. albicans DNA was examined on an agarose gel. Sequence analysis of the cloned element revealed that it is a retrotransposon belonging to the Ty1/copia group. It is estimated that pCal produces 50 to 100 free, linear, dsDNA copies of itself per cell. This is a much higher level of expression than even that of the system in which Ty1 is expressed behind the highly active GAL1 promoter on a high-copy-number plasmid (about 10 copies per cell). Another unusual feature of pCal is that its Pol enzymes are likely to be expressed via the pseudoknot-assisted suppression of an upstream, in-phase stop codon, as has been shown for Moloney murine leukemia virus.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Candida albicans/genetics
- Chromosome Mapping
- Cloning, Molecular
- Codon, Terminator
- DNA Transposable Elements/genetics
- DNA, Fungal/analysis
- DNA, Fungal/genetics
- DNA, Fungal/isolation & purification
- Endopeptidases/genetics
- Gene Expression Regulation, Fungal
- Gene Products, pol/genetics
- Gene Products, pol/metabolism
- Integrases/genetics
- Molecular Sequence Data
- Molecular Structure
- Open Reading Frames
- Phylogeny
- Plasmids
- Promoter Regions, Genetic
- RNA-Directed DNA Polymerase/genetics
- Retroelements
- Ribonucleases/genetics
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
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Affiliation(s)
- G D Matthews
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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16
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Levin HL. An unusual mechanism of self-primed reverse transcription requires the RNase H domain of reverse transcriptase to cleave an RNA duplex. Mol Cell Biol 1996; 16:5645-54. [PMID: 8816477 PMCID: PMC231564 DOI: 10.1128/mcb.16.10.5645] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The reverse transcription of retroviruses and long terminal repeat-containing retrotransposons requires that tRNA species serve as primers. We recently reported that the long terminal repeat-containing retrotransposon Tf1 is a unique exception in that reverse transcription is independent of tRNA and is instead initiated by a self-priming mechanism. The first 11 bases of the Tf1 transcript fold back and anneal to the primer binding site in a process that results in the priming of minus-strand strong-stop DNA. Data presented here demonstrate that a cleavage occurs between the 11th and 12th bases of the transcript, resulting in the generation of the primer. Mutagenesis experiments presented here indicate that the RNase H domain of the Tf1 reverse transcriptase is required for the cleavage reaction, suggesting that this RNase H may have the novel ability to cleave double-stranded RNA at the end of a duplexed region.
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Affiliation(s)
- H L Levin
- Laboratory of Eukaryotic Gene Regulation, National Institute of Child Health and Human Development, Bethesda, Maryland 20892, USA.
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17
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Kikuchi Y. RNase P as hyperprocessing enzyme: a model for formation of a biologically functional tRNA fragment. Mol Biol Rep 1996; 22:171-5. [PMID: 8901506 DOI: 10.1007/bf00988724] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Hyperprocessing is defined as a further processing of mature RNA that produces another functional RNA. Hyperprocessing occurs in Drosophila cells. In the transposon copia-related retrovirus-like particles of Drosophila, a 39-nucleotide-long fragment from the 5'region of Drosophila initiator methionine tRNA is used as the primer for copia minus-strand reverse transcription. This primer tRNA fragment is thought to be produced by cleavage within the mature tRNA sequence. We found that the catalytic RNA subunit of RNase P catalyzes this hyperprocessing in vitro and that this cleavage is dependent of the occurrence of an altered conformation of the tRNA substrate. In this review, I will summarize our work from the finding of the functional RNA fragment to the finding of a dynamic tRNA structure.
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Affiliation(s)
- Y Kikuchi
- Department of Ecological Engineering, Toyohashi University of Technology, Japan
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18
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Chamberlain JR, Tranguch AJ, Pagán-Ramos E, Engelke DR. Eukaryotic nuclear RNase P: structures and functions. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1996; 55:87-119. [PMID: 8787607 DOI: 10.1016/s0079-6603(08)60190-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- J R Chamberlain
- Program in Cellular and Molecular Biology, The University of Michigan Medical School, Ann Arbor 48109, USA
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19
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Dick TP, Schamel WA. Molecular evolution of transfer RNA from two precursor hairpins: implications for the origin of protein synthesis. J Mol Evol 1995; 41:1-9. [PMID: 7608982 DOI: 10.1007/bf00174035] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In this paper we are going to present a model for the coevolution of major components of the protein synthesis machinery in a primordial RNA world. We propose that the essential prerequisites for RNA-based protein synthesis, i.e., tRNA-like molecules, ribozymic charging catalysts, small-subunit(SSU) rRNA, and large-subunit(LSU) rRNA, evolved from the same ancestral RNA molecule. Several arguments are considered which suggest that tRNA-like molecules were derived by tandem joining of template-flanking hairpin structures involved in replication control. It is further argued that the ancestors of contemporary group I tRNA introns catalyzed such hairpin joining reactions, themselves also giving rise to the ribosomal RNAs. Our model includes a general stereochemical principle for the interaction between ribozymes and hairpin-derived recognition structures, which can be applied to such seemingly different processes as RNA polymerization, aminoacylation, tRNA decoding, and peptidyl transfer, implicating a common origin for these fundamental functions. These and other considerations suggest that generation and evolution of tRNA were coupled to the evolution of synthetases, ribosomal RNAs, and introns from the beginning and have been a consequence arising from the original function of tRNA precursor hairpins as replication and recombination control elements.
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Affiliation(s)
- T P Dick
- Department of Tumorvirus-Immunology, German Cancer Research Center, Heidelberg
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20
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Pergolizzi RG, Erster SH. Analysis of chromosome 22 loci in meningioma. Alterations in the leukemia inhibitory factor (LIF) locus. MOLECULAR AND CHEMICAL NEUROPATHOLOGY 1994; 21:189-217. [PMID: 7916188 DOI: 10.1007/bf02815351] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Meningiomas are typically benign tumors arising from arachnoidal cells at the base of the brain. Meningioma is thought to result from the loss or inactivation of a putative tumor suppressor gene located on chromosome 22. We analyzed a set of meningioma DNA specimens by Southern blot hybridization with chromosome 22-specific probes and by PCR using oligomer primers and probes specific to the leukemia inhibitory factor (LIF) gene. Southern analysis suggested that a subset of our specimens are monosomic for 22q11-qter and may have lost one entire copy of chromosome 22. The gene(s) involved in the etiology of meningioma has been localized to 22q11.2-12.3. The locus encoding LIF, a factor that affects the differentiation and proliferation of numerous cell types, has also been localized to this region, at 22q12.1-12.2. The partial overlap of these loci, coupled with the known involvement of the LIF gene product in growth and differentiation, suggested that the LIF locus may be associated with the meningioma defect. We have examined the LIF locus in meningioma specimens at the molecular level by PCR, and by DNA and RNA gel-blot hybridizations. Alterations in the structure and/or expression of the LIF locus were detected in several specimens, including the subset that were shown to be monosomic for 22q. All of our tumor specimens were shown to be undermethylated at the LIF locus relative to constitutional DNA from the same patients. Sequence analysis of LIF cDNA from a meningioma revealed the existence of a novel, alternatively spliced LIF mRNA. These results suggest that the LIF gene may be near the putative tumor suppressor locus associated with the development of this phenotype.
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Affiliation(s)
- R G Pergolizzi
- Department of Pathology, North Shore University Hospital, Cornell University Medical College, Manhasset, NY 11030
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21
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Kikuchi Y, Sasaki-Tozawa N, Suzuki K. Artificial self-cleaving molecules consisting of a tRNA precursor and the catalytic RNA of RNase P. Nucleic Acids Res 1993; 21:4685-9. [PMID: 8233817 PMCID: PMC331491 DOI: 10.1093/nar/21.20.4685] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We synthesized two types of chimeric RNAs between the catalytic RNA subunit of RNase P from Escherichia coli (M1 RNA) and a tRNA precursor (pre-tRNA); one had pre-tRNA at the 3' side to the M1 RNA (M1 RNA-pre-tRNA). The second had pre-tRNA at the 5' side of the M1 RNA (pre-tRNA-M1 RNA). Both molecules were self-cleaving RNAs. The self-cleavage of M1 RNA-pre-tRNA occurred at the normal site (5'-end of mature tRNA sequence) and proceeded under the condition of 10 mM Mg2+ concentration. This reaction at 10 mM Mg2+ was an intramolecular reaction (cis-cleavage), while, at 40 mM and 80 mM Mg2+, trans-cleavage partially occurred. The self-cleavage rate was strictly affected by the distance between the M1 RNA and the pre-tRNA in the molecule. The self-cleavage of pre-tRNA-M1 RNA occurred mainly at three sites within the mature tRNA sequence. This cleavage did not occur at 10 mM Mg2+. Use of M1 RNA-pre-tRNA molecule for the in vitro evolution of M1 RNA is discussed.
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Affiliation(s)
- Y Kikuchi
- Mitsubishi Kasei Institute of Life Sciences, Tokyo, Japan
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22
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Nashimoto M. 3' truncated tRNAArg is essential for in vitro specific cleavage of partially synthesized mouse 18S rRNA. Nucleic Acids Res 1993; 21:4696-702. [PMID: 8233818 PMCID: PMC331493 DOI: 10.1093/nar/21.20.4696] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
In vitro synthesized 5' portions of mouse 18S rRNA are cleaved efficiently at a specific site in partially purified extracts of mouse FM3A cells and several mouse tissues. This activity is composed of both protein and RNA, and can be reconstituted with the protein component in micrococcal nuclease-treated extracts and the RNA component in phenol-treated ones. The RNA component of about 65 nucleotides with the complementing activity was purified from total RNA in the partially purified FM3A cell extracts by polyacrylamide gel electrophoreses. Chemical sequencing of this RNA elucidated that it is tRNAArg lacking nine nucleotides from its 3' terminus. Ribonuclease H treatment directed by deoxyoligonucleotides complementary to tRNAArg completely abolishes the cleavage activity, supporting the above conclusion.
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Affiliation(s)
- M Nashimoto
- Department of Biochemistry, Hokkaido University School of Medicine, Sapporo, Japan
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23
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Kikuchi Y, Sasaki N. Hyperprocessing of tRNA by the catalytic RNA of RNase P. Cleavage of a natural tRNA within the mature tRNA sequence and evidence for an altered conformation of the substrate tRNA. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)49792-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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24
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Kikuchi Y, Sasaki N. Site-specific cleavage of natural mRNA sequences by newly designed hairpin catalytic RNAs. Nucleic Acids Res 1991; 19:6751-5. [PMID: 1762907 PMCID: PMC329305 DOI: 10.1093/nar/19.24.6751] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The negative strand of tobacco ringspot virus satellite RNA is a self-cleaving RNA. Its catalytic domain and substrate domain have been identified, and the catalytic domain has been named hairpin catalytic RNA. Here we report the construction of a plasmid containing a modified hairpin catalytic RNA sequence that can be transcribed in vitro. Because this plasmid has two specific restriction enzyme recognition sites at both ends of the substrate binding site in the catalytic RNA sequence, it is possible to construct new plasmids by substituting different sequences in the substrate binding site. Using this plasmid, synthetic DNA, and in vitro transcription, we obtained three ribozymes designed to cleave Escherichia coli prolipoprotein signal peptidase (lsp) mRNA at specific sites. All three ribozymes cleaved the lsp mRNA sequence in vitro at the specific sites, and two of them cleaved it efficiently. Kinetic analyses showed that one had a higher kcat/Km value than that of the well-known hammerhead ribozyme. Problems associated with attaining the goal of expressing these ribozymes in vivo also are discussed.
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Affiliation(s)
- Y Kikuchi
- Department of Molecular Biology, Mitsubishi Kasei Institute of Life Sciences, Tokyo, Japan
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25
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Rhim H, Park J, Morrow CD. Deletions in the tRNA(Lys) primer-binding site of human immunodeficiency virus type 1 identify essential regions for reverse transcription. J Virol 1991; 65:4555-64. [PMID: 1714513 PMCID: PMC248909 DOI: 10.1128/jvi.65.9.4555-4564.1991] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The initiation of human immunodeficiency virus type 1 (HIV-1) reverse transcription occurs by the extension of a tRNA primer bound near the 5' end of the genomic RNA at a position termed the primer-binding site (PBS). The PBS is an 18-nucleotide region of the HIV-1 genome complementary to cellular tRNA(Lys). To further investigate the sequence requirements for the PBS in reverse transcription, deletions in the PBS were created and subcloned into a plasmid containing the infectious HIV-1 proviral genome. The mutations deleted the entire PBS (delta PBS) or the first 9 (delta 1-9), the second 9 (delta 10-18), or 12 (delta 7-18) nucleotides of the PBS. An additional mutation in the PBS was created in which the second nine nucleotides were deleted and nine additional nucleotides were substituted [Lys(1-9)]. The transfection of plasmids containing the wild-type or mutant proviral genomes into tissue culture cells resulted in expression of the HIV-1 gag and env gene products, as determined by immunoprecipitation using sera from AIDS patients. HIV-1 virus was released from the transfected cells, as determined by analysis of the supernatants for reverse transcriptase activity. The infectivity of the viruses derived from the transfection was examined by coculture experiments with SupT1 cells, which support high-level replication of HIV-1. The transfection of plasmids containing HIV-1 proviral genomes with the delta PBS and PBS (delta 1-9) mutations did not produce infectious virus. In contrast, the HIV-1 proviral genomes with the delta 10-18, delta 7-18, and Lys(1-9) mutations in the PBS produced infectious virus upon transfection, although the kinetics of appearance was significantly delayed for the mutant viruses compared with the wild type. To further explore the nature of this defect, the PBS region from integrated proviral genomes was amplified by polymerase chain reaction and individual DNA products were subcloned into M13mp19, followed by a sequence analysis of the PBS region from individual M13 phage clones. In each of the PBS regions examined, the 18-nucleotide PBS complementary to tRNA(Lys) was present. However, nucleotide deletions and insertions were found 3' to the PBS from the samples derived from the transfection of plasmids containing mutant proviral genomes. Upon reinfection, the revertant viruses maintained the deletions 3' to the PBS and had kinetics of replication similar to that of the wild-type virus.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- H Rhim
- Department of Microbiology, University of Alabama, Birmingham 35294
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