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Elder JJH, Papadopoulos R, Hayne CK, Stanley RE. The making and breaking of tRNAs by ribonucleases. Trends Genet 2024; 40:511-525. [PMID: 38641471 DOI: 10.1016/j.tig.2024.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/21/2024] [Accepted: 03/21/2024] [Indexed: 04/21/2024]
Abstract
Ribonucleases (RNases) play important roles in supporting canonical and non-canonical roles of tRNAs by catalyzing the cleavage of the tRNA phosphodiester backbone. Here, we highlight how recent advances in cryo-electron microscopy (cryo-EM), protein structure prediction, reconstitution experiments, tRNA sequencing, and other studies have revealed new insight into the nucleases that process tRNA. This represents a very diverse group of nucleases that utilize distinct mechanisms to recognize and cleave tRNA during different stages of a tRNA's life cycle including biogenesis, fragmentation, surveillance, and decay. In this review, we provide a synthesis of the structure, mechanism, regulation, and modes of tRNA recognition by tRNA nucleases, along with open questions for future investigation.
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Affiliation(s)
- Jessica J H Elder
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Ry Papadopoulos
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA; Department of Chemistry, University of Chicago, Chicago, IL, USA
| | - Cassandra K Hayne
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA.
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA.
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2
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Liu Q, Wu Z, Tian C, Yang Y, Liu L, Feng Y, Li Z. Complete mitochondrial genome of the endangered Prunus pedunculata (Prunoideae, Rosaceae) in China: characterization and phylogenetic analysis. FRONTIERS IN PLANT SCIENCE 2023; 14:1266797. [PMID: 38155854 PMCID: PMC10753190 DOI: 10.3389/fpls.2023.1266797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/20/2023] [Indexed: 12/30/2023]
Abstract
Introduction Prunus pedunculata (Prunoideae: Rosaceae), a relic shrub with strong resistance and multiple application values, is endangered in China. Extensive research had been devoted to gene expression, molecular markers, plastid genome analysis, and genetic background investigations of P. pedunculata. However, the mitochondrial genome of this species has not been systematically described, owing to the complexity of the plant mitogenome. Methods In the present research, the complete mitochondrial genome of P. pedunculata was assembled, annotated, and characterized. The genomic features, gene content and repetitive sequences were analyzed. The genomic variation and phylogenetic analysis have been extensively enumerated. Results and discussion The P. pedunculata mitogenome is a circular molecule with a total length of 405,855 bp and a GC content of 45.63%, which are the smallest size and highest GC content among the known Prunus mitochondrial genomes. The mitogenome of P. pedunculata encodes 62 genes, including 34 unique protein-coding genes (PCGs, excluding three possible pseudogenes), three ribosomal RNA genes, and 19 transfer RNA genes. The mitogenome is rich in repetitive sequences, counting 112 simple sequence repeats, 15 tandem repeats, and 50 interspersed repetitive sequences, with a total repeat length of 11,793 bp, accounting for 2.91% of the complete genome. Leucine (Leu) was a predominant amino acid in PCGs, with a frequency of 10.67%, whereas cysteine (Cys) and tryptophan (Trp) were the least adopted. The most frequently used codon was UUU (Phe), with a relative synonymous codon usage (RSCU) value of 1.12. Selective pressure was calculated based on 20 shared PCGs in the mitogenomes of the 32 species, most of which were subjected to purifying selection (Ka/Ks < 1), whereas ccmC and ccmFn underwent positive selection. A total of 262 potential RNA editing sites in 26 PCGs were identified. Furthermore, 56 chloroplast-derived fragments were ascertained in the mitogenome, ranging from 30 to 858 bp, and were mainly located across IGS (intergenic spacer) regions or rRNA genes. These findings verify the occurrence of intracellular gene transfer events from the chloroplast to the mitochondria. Furthermore, the phylogenetic relationship of P. pedunculata was supported by the mitogenome data of 30 other taxa of the Rosaceae family. Understanding the mitochondrial genome characteristics of P. pedunculata is of great importance to promote comprehension of its genetic background and this study provides a basis for the genetic breeding of Prunus.
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Affiliation(s)
- Qian Liu
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, China
| | - Zinian Wu
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, China
- Key Laboratory of Grassland Resources and Utilization of Ministry of Agriculture, Hohhot, China
| | - Chunyu Tian
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, China
| | - Yanting Yang
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, China
| | - Lemeng Liu
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, China
| | - Yumei Feng
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, China
| | - Zhiyong Li
- Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, China
- Key Laboratory of Grassland Resources and Utilization of Ministry of Agriculture, Hohhot, China
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3
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Akiyama Y, Ivanov P. tRNA-derived RNAs: Biogenesis and roles in translational control. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1805. [PMID: 37406666 PMCID: PMC10766869 DOI: 10.1002/wrna.1805] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 05/17/2023] [Accepted: 06/06/2023] [Indexed: 07/07/2023]
Abstract
Transfer RNA (tRNA)-derived RNAs (tDRs) are a class of small non-coding RNAs that play important roles in different aspects of gene expression. These ubiquitous and heterogenous RNAs, which vary across different species and cell types, are proposed to regulate various biological processes. In this review, we will discuss aspects of their biogenesis, and specifically, their contribution into translational control. We will summarize diverse roles of tDRs and the molecular mechanisms underlying their functions in the regulation of protein synthesis and their impact on related events such as stress-induced translational reprogramming. This article is categorized under: RNA Processing > Processing of Small RNAs Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs Regulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs.
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Affiliation(s)
- Yasutoshi Akiyama
- Laboratory of Oncology, Pharmacy Practice and Sciences, Tohoku University Graduate School of Pharmaceutical Sciences, Sendai, Japan
| | - Pavel Ivanov
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
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4
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Hayne CK, Sekulovski S, Hurtig JE, Stanley RE, Trowitzsch S, van Hoof A. New insights into RNA processing by the eukaryotic tRNA splicing endonuclease. J Biol Chem 2023; 299:105138. [PMID: 37544645 PMCID: PMC10485636 DOI: 10.1016/j.jbc.2023.105138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/27/2023] [Accepted: 07/29/2023] [Indexed: 08/08/2023] Open
Abstract
Through its role in intron cleavage, tRNA splicing endonuclease (TSEN) plays a critical function in the maturation of intron-containing pre-tRNAs. The catalytic mechanism and core requirement for this process is conserved between archaea and eukaryotes, but for decades, it has been known that eukaryotic TSENs have evolved additional modes of RNA recognition, which have remained poorly understood. Recent research identified new roles for eukaryotic TSEN, including processing or degradation of additional RNA substrates, and determined the first structures of pre-tRNA-bound human TSEN complexes. These recent discoveries have changed our understanding of how the eukaryotic TSEN targets and recognizes substrates. Here, we review these recent discoveries, their implications, and the new questions raised by these findings.
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Affiliation(s)
- Cassandra K Hayne
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA.
| | - Samoil Sekulovski
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Jennifer E Hurtig
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center, Houston, Texas, USA
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National, Institutes of Health, Research Triangle Park, North Carolina, USA.
| | - Simon Trowitzsch
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Frankfurt am Main, Germany.
| | - Ambro van Hoof
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center, Houston, Texas, USA.
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5
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Abstract
The study of eukaryotic tRNA processing has given rise to an explosion of new information and insights in the last several years. We now have unprecedented knowledge of each step in the tRNA processing pathway, revealing unexpected twists in biochemical pathways, multiple new connections with regulatory pathways, and numerous biological effects of defects in processing steps that have profound consequences throughout eukaryotes, leading to growth phenotypes in the yeast Saccharomyces cerevisiae and to neurological and other disorders in humans. This review highlights seminal new results within the pathways that comprise the life of a tRNA, from its birth after transcription until its death by decay. We focus on new findings and revelations in each step of the pathway including the end-processing and splicing steps, many of the numerous modifications throughout the main body and anticodon loop of tRNA that are so crucial for tRNA function, the intricate tRNA trafficking pathways, and the quality control decay pathways, as well as the biogenesis and biology of tRNA-derived fragments. We also describe the many interactions of these pathways with signaling and other pathways in the cell.
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Affiliation(s)
- Eric M Phizicky
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine, Rochester, New York 14642, USA
| | - Anita K Hopper
- Department of Molecular Genetics and Center for RNA Biology, Ohio State University, Columbus, Ohio 43235, USA
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6
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Hayne CK, Butay KJU, Stewart ZD, Krahn JM, Perera L, Williams JG, Petrovitch RM, Deterding LJ, Matera AG, Borgnia MJ, Stanley RE. Structural basis for pre-tRNA recognition and processing by the human tRNA splicing endonuclease complex. Nat Struct Mol Biol 2023; 30:824-833. [PMID: 37231153 PMCID: PMC10627149 DOI: 10.1038/s41594-023-00991-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 04/06/2023] [Indexed: 05/27/2023]
Abstract
Throughout bacteria, archaea and eukarya, certain tRNA transcripts contain introns. Pre-tRNAs with introns require splicing to form the mature anticodon stem loop. In eukaryotes, tRNA splicing is initiated by the heterotetrameric tRNA splicing endonuclease (TSEN) complex. All TSEN subunits are essential, and mutations within the complex are associated with a family of neurodevelopmental disorders known as pontocerebellar hypoplasia (PCH). Here, we report cryo-electron microscopy structures of the human TSEN-pre-tRNA complex. These structures reveal the overall architecture of the complex and the extensive tRNA binding interfaces. The structures share homology with archaeal TSENs but contain additional features important for pre-tRNA recognition. The TSEN54 subunit functions as a pivotal scaffold for the pre-tRNA and the two endonuclease subunits. Finally, the TSEN structures enable visualization of the molecular environments of PCH-causing missense mutations, providing insight into the mechanism of pre-tRNA splicing and PCH.
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Affiliation(s)
- Cassandra K Hayne
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA.
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA.
| | - Kevin John U Butay
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Zachary D Stewart
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
- Georgetown University, Washington, DC, USA
| | - Juno M Krahn
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Lalith Perera
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Jason G Williams
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Robert M Petrovitch
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Leesa J Deterding
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - A Gregory Matera
- Integrative Program for Biological and Genome Sciences, Departments of Biology and Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - Mario J Borgnia
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA.
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7
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Affiliation(s)
- Anita K Hopper
- Department of Molecular Genetics and Center for RNA Biology, Ohio State University, Columbus, OH, USA.
| | - Jinwei Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA.
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Zhang X, Yang F, Zhan X, Bian T, Xing Z, Lu Y, Shi Y. Structural basis of pre-tRNA intron removal by human tRNA splicing endonuclease. Mol Cell 2023; 83:1328-1339.e4. [PMID: 37028420 DOI: 10.1016/j.molcel.2023.03.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 01/17/2023] [Accepted: 03/14/2023] [Indexed: 04/09/2023]
Abstract
Removal of the intron from precursor-tRNA (pre-tRNA) is essential in all three kingdoms of life. In humans, this process is mediated by the tRNA splicing endonuclease (TSEN) comprising four subunits: TSEN2, TSEN15, TSEN34, and TSEN54. Here, we report the cryo-EM structures of human TSEN bound to full-length pre-tRNA in the pre-catalytic and post-catalytic states at average resolutions of 2.94 and 2.88 Å, respectively. Human TSEN features an extended surface groove that holds the L-shaped pre-tRNA. The mature domain of pre-tRNA is recognized by conserved structural elements of TSEN34, TSEN54, and TSEN2. Such recognition orients the anticodon stem of pre-tRNA and places the 3'-splice site and 5'-splice site into the catalytic centers of TSEN34 and TSEN2, respectively. The bulk of the intron sequences makes no direct interaction with TSEN, explaining why pre-tRNAs of varying introns can be accommodated and cleaved. Our structures reveal the molecular ruler mechanism of pre-tRNA cleavage by TSEN.
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Affiliation(s)
- Xiaofeng Zhang
- Research Center for Industries of the Future, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; Westlake Laboratory of Life Sciences and Biomedicine, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China.
| | - Fenghua Yang
- Research Center for Industries of the Future, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; Westlake Laboratory of Life Sciences and Biomedicine, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; College of Life Sciences, Fudan University, Shanghai 200433, China
| | - Xiechao Zhan
- Research Center for Industries of the Future, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; Westlake Laboratory of Life Sciences and Biomedicine, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China
| | - Tong Bian
- Research Center for Industries of the Future, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; Westlake Laboratory of Life Sciences and Biomedicine, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; College of Life Sciences, Fudan University, Shanghai 200433, China
| | - Zhihan Xing
- Research Center for Industries of the Future, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; Westlake Laboratory of Life Sciences and Biomedicine, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China
| | - Yichen Lu
- Research Center for Industries of the Future, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; Westlake Laboratory of Life Sciences and Biomedicine, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China
| | - Yigong Shi
- Research Center for Industries of the Future, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; Westlake Laboratory of Life Sciences and Biomedicine, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China; College of Life Sciences, Fudan University, Shanghai 200433, China; Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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9
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Villarreal L, Witzany G. Self-empowerment of life through RNA networks, cells and viruses. F1000Res 2023; 12:138. [PMID: 36785664 PMCID: PMC9918806 DOI: 10.12688/f1000research.130300.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/20/2023] [Indexed: 01/05/2024] Open
Abstract
Our understanding of the key players in evolution and of the development of all organisms in all domains of life has been aided by current knowledge about RNA stem-loop groups, their proposed interaction motifs in an early RNA world and their regulative roles in all steps and substeps of nearly all cellular processes, such as replication, transcription, translation, repair, immunity and epigenetic marking. Cooperative evolution was enabled by promiscuous interactions between single-stranded regions in the loops of naturally forming stem-loop structures in RNAs. It was also shown that cooperative RNA stem-loops outcompete selfish ones and provide foundational self-constructive groups (ribosome, editosome, spliceosome, etc.). Self-empowerment from abiotic matter to biological behavior does not just occur at the beginning of biological evolution; it is also essential for all levels of socially interacting RNAs, cells and viruses.
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Affiliation(s)
- Luis Villarreal
- Center for Virus Research, University of California, Irvine, California, USA
| | - Guenther Witzany
- Telos - Philosophische Praxis, Buermoos, Salzburg, 5111, Austria
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10
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Villarreal L, Witzany G. Self-empowerment of life through RNA networks, cells and viruses. F1000Res 2023; 12:138. [PMID: 36785664 PMCID: PMC9918806 DOI: 10.12688/f1000research.130300.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/23/2023] [Indexed: 03/08/2023] Open
Abstract
Our understanding of the key players in evolution and of the development of all organisms in all domains of life has been aided by current knowledge about RNA stem-loop groups, their proposed interaction motifs in an early RNA world and their regulative roles in all steps and substeps of nearly all cellular processes, such as replication, transcription, translation, repair, immunity and epigenetic marking. Cooperative evolution was enabled by promiscuous interactions between single-stranded regions in the loops of naturally forming stem-loop structures in RNAs. It was also shown that cooperative RNA stem-loops outcompete selfish ones and provide foundational self-constructive groups (ribosome, editosome, spliceosome, etc.). Self-empowerment from abiotic matter to biological behavior does not just occur at the beginning of biological evolution; it is also essential for all levels of socially interacting RNAs, cells and viruses.
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Affiliation(s)
- Luis Villarreal
- Center for Virus Research, University of California, Irvine, California, USA
| | - Guenther Witzany
- Telos - Philosophische Praxis, Buermoos, Salzburg, 5111, Austria
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Sekulovski S, Trowitzsch S. What connects splicing of transfer RNA precursor molecules with pontocerebellar hypoplasia? Bioessays 2023; 45:e2200130. [PMID: 36517085 DOI: 10.1002/bies.202200130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 01/19/2023]
Abstract
Transfer RNAs (tRNAs) represent the most abundant class of RNA molecules in the cell and are key players during protein synthesis and cellular homeostasis. Aberrations in the extensive tRNA biogenesis pathways lead to severe neurological disorders in humans. Mutations in the tRNA splicing endonuclease (TSEN) and its associated RNA kinase cleavage factor polyribonucleotide kinase subunit 1 (CLP1) cause pontocerebellar hypoplasia (PCH), a heterogeneous group of neurodegenerative disorders, that manifest as underdevelopment of specific brain regions typically accompanied by microcephaly, profound motor impairments, and child mortality. Recently, we demonstrated that mutations leading to specific PCH subtypes destabilize TSEN in vitro and cause imbalances of immature to mature tRNA ratios in patient-derived cells. However, how tRNA processing defects translate to disease on a systems level has not been understood. Recent findings suggested that other cellular processes may be affected by mutations in TSEN/CLP1 and obscure the molecular mechanisms of PCH emergence. Here, we review PCH disease models linked to the TSEN/CLP1 machinery and discuss future directions to study neuropathogenesis.
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Affiliation(s)
- Samoil Sekulovski
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Frankfurt/Main, Germany
| | - Simon Trowitzsch
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Frankfurt/Main, Germany
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