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Jiang D, Kejiou N, Qiu Y, Palazzo AF, Pennell M. Genetic and selective constraints on the optimization of gene product diversity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.17.603951. [PMID: 39091777 PMCID: PMC11291005 DOI: 10.1101/2024.07.17.603951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
RNA and protein expressed from the same gene can have diverse isoforms due to various post-transcriptional and post-translational modifications. For the vast majority of alternative isoforms, It is unknown whether they are adaptive or simply biological noise. As we cannot experimentally probe the function of each isoform, we can ask whether the distribution of isoforms across genes and across species is consistent with expectations from different evolutionary processes. However, there is currently no theoretical framework that can generate such predictions. To address this, we developed a mathematical model where isoform abundances are determined collectively by cis -acting loci, trans -acting factors, gene expression levels, and isoform decay rates to predict isoform abundance distributions across species and genes in the face of mutation, genetic drift, and selection. We found that factors beyond selection, such as effective population size and the number of cis -acting loci, significantly influence evolutionary outcomes. Notably, suboptimal phenotypes are more likely to evolve when the population is small and/or when the number of cis -loci is large. We also explored scenarios where modification processes have both beneficial and detrimental effects, revealing a non-monotonic relationship between effective population size and optimization, demonstrating how opposing selection pressures on cis - and trans -acting loci can constrain the optimization of gene product diversity. As a demonstration of the power of our theory, we compared the expected distribution of A-to-I RNA editing levels in coleoids and found this to be largely consistent with non-adaptive explanations.
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Affiliation(s)
- Daohan Jiang
- Department of Quantitative and Computational Biology, University of Southern California, USA
| | - Nevraj Kejiou
- Department of Biochemistry, University of Toronto, Canada
| | - Yi Qiu
- Department of Biochemistry, University of Toronto, Canada
| | | | - Matt Pennell
- Department of Quantitative and Computational Biology, University of Southern California, USA
- Department of Biological Sciences, University of Southern California, USA
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2
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Ma L, Zheng C, Liu J, Song F, Tian L, Cai W, Li H, Duan Y. Learning from the Codon Table: Convergent Recoding Provides Novel Understanding on the Evolution of A-to-I RNA Editing. J Mol Evol 2024:10.1007/s00239-024-10190-z. [PMID: 39012510 DOI: 10.1007/s00239-024-10190-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Accepted: 07/09/2024] [Indexed: 07/17/2024]
Abstract
Adenosine-to-inosine (A-to-I) RNA editing recodes the genetic information. Apart from diversifying the proteome, another tempting advantage of RNA recoding is to correct deleterious DNA mutation and restore ancestral allele. Solid evidences for beneficial restorative editing are very rare in animals. By searching for "convergent recoding" under a phylogenetic context, we proposed this term for judging the potential restorative functions of particular editing site. For the well-known mammalian Gln>Arg (Q>R) recoding site, its ancestral state in vertebrate genomes was the pre-editing Gln, and all 470 available mammalian genomes strictly avoid other three equivalent ways to achieve Arg in protein. The absence of convergent recoding from His>Arg, or synonymous mutations on Gln codons, could be attributed to the strong maintenance on editing motif and structure, but the absence of direct A-to-G mutation is extremely unexpected. With similar ideas, we found cases of convergent recoding in Drosophila genus, reducing the possibility of their restorative function. In summary, we defined an interesting scenario of convergent recoding, the occurrence of which could be used as preliminary judgements for whether a recoding site has a sole restorative role. Our work provides novel insights to the natural selection and evolution of RNA editing.
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Affiliation(s)
- Ling Ma
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Caiqing Zheng
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Jiyao Liu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Fan Song
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Li Tian
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Wanzhi Cai
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Hu Li
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Yuange Duan
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China.
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Bénitière F, Duret L, Necsulea A. GTDrift: a resource for exploring the interplay between genetic drift, genomic and transcriptomic characteristics in eukaryotes. NAR Genom Bioinform 2024; 6:lqae064. [PMID: 38867915 PMCID: PMC11167491 DOI: 10.1093/nargab/lqae064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 04/22/2024] [Accepted: 05/27/2024] [Indexed: 06/14/2024] Open
Abstract
We present GTDrift, a comprehensive data resource that enables explorations of genomic and transcriptomic characteristics alongside proxies of the intensity of genetic drift in individual species. This resource encompasses data for 1506 eukaryotic species, including 1413 animals and 93 green plants, and is organized in three components. The first two components contain approximations of the effective population size, which serve as indicators of the extent of random genetic drift within each species. In the first component, we meticulously investigated public databases to assemble data on life history traits such as longevity, adult body length and body mass for a set of 979 species. The second component includes estimations of the ratio between the rate of non-synonymous substitutions and the rate of synonymous substitutions (dN/dS) in protein-coding sequences for 1324 species. This ratio provides an estimate of the efficiency of natural selection in purging deleterious substitutions. Additionally, we present polymorphism-derived N e estimates for 66 species. The third component encompasses various genomic and transcriptomic characteristics. With this component, we aim to facilitate comparative transcriptomics analyses across species, by providing easy-to-use processed data for more than 16 000 RNA-seq samples across 491 species. These data include intron-centered alternative splicing frequencies, gene expression levels and sequencing depth statistics for each species, obtained with a homogeneous analysis protocol. To enable cross-species comparisons, we provide orthology predictions for conserved single-copy genes based on BUSCO gene sets. To illustrate the possible uses of this database, we identify the most frequently used introns for each gene and we assess how the sequencing depth available for each species affects our power to identify major and minor splice variants.
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Affiliation(s)
- Florian Bénitière
- Laboratoire de Biométrie et Biologie Évolutive, Université Lyon 1, UMR CNRS 5558, Villeurbanne, France
- Laboratoire d’Écologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1, UMR CNRS 5023, Villeurbanne, France
| | - Laurent Duret
- Laboratoire de Biométrie et Biologie Évolutive, Université Lyon 1, UMR CNRS 5558, Villeurbanne, France
| | - Anamaria Necsulea
- Laboratoire de Biométrie et Biologie Évolutive, Université Lyon 1, UMR CNRS 5558, Villeurbanne, France
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4
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Liu J, Zheng C, Duan Y. New comparative genomic evidence supporting the proteomic diversification role of A-to-I RNA editing in insects. Mol Genet Genomics 2024; 299:46. [PMID: 38642133 DOI: 10.1007/s00438-024-02141-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 12/29/2023] [Indexed: 04/22/2024]
Abstract
Adenosine-to-inosine (A-to-I) RNA editing, resembling A-to-G mutation, confers adaptiveness by increasing proteomic diversity in a temporal-spatial manner. This evolutionary theory named "proteomic diversifying hypothesis" has only partially been tested in very few organisms like Drosophila melanogaster, mainly by observing the positive selection on nonsynonymous editing events. To find additional genome-wide evidences supporting this interesting assumption, we retrieved the genomes of four Drosophila species and collected 20 deep-sequenced transcriptomes of different developmental stages and neuron populations of D. melanogaster. We systematically profiled the RNA editomes in these samples and performed meticulous comparative genomic analyses. Further evidences were found to support the diversifying hypothesis. (1) None of the nonsynonymous editing sites in D. melanogaster had ancestral G-alleles, while the silent editing sites had an unignorable fraction of ancestral G-alleles; (2) Only very few nonsynonymous editing sites in D. melanogaster had corresponding G-alleles derived in the genomes of sibling species, and the fraction of such situation was significantly lower than that of silent editing sites; (3) The few nonsynonymous editing with corresponding G-alleles had significantly more variable editing levels (across samples) than other nonsynonymous editing sites in D. melanogaster. The proteomic diversifying nature of RNA editing in Drosophila excludes the restorative role which favors an ancestral G-allele. The few fixed G-alleles in sibling species might facilitate the adaptation to particular environment and the corresponding nonsynonymous editing in D. melanogaster would introduce stronger advantage of flexible proteomic diversification. With multi-Omics data, our study consolidates the nature of evolutionary significance of A-to-I RNA editing sites in model insects.
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Affiliation(s)
- Jiyao Liu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Caiqing Zheng
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Yuange Duan
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China.
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5
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Bénitière F, Necsulea A, Duret L. Random genetic drift sets an upper limit on mRNA splicing accuracy in metazoans. eLife 2024; 13:RP93629. [PMID: 38470242 DOI: 10.7554/elife.93629] [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] [Indexed: 03/13/2024] Open
Abstract
Most eukaryotic genes undergo alternative splicing (AS), but the overall functional significance of this process remains a controversial issue. It has been noticed that the complexity of organisms (assayed by the number of distinct cell types) correlates positively with their genome-wide AS rate. This has been interpreted as evidence that AS plays an important role in adaptive evolution by increasing the functional repertoires of genomes. However, this observation also fits with a totally opposite interpretation: given that 'complex' organisms tend to have small effective population sizes (Ne), they are expected to be more affected by genetic drift, and hence more prone to accumulate deleterious mutations that decrease splicing accuracy. Thus, according to this 'drift barrier' theory, the elevated AS rate in complex organisms might simply result from a higher splicing error rate. To test this hypothesis, we analyzed 3496 transcriptome sequencing samples to quantify AS in 53 metazoan species spanning a wide range of Ne values. Our results show a negative correlation between Ne proxies and the genome-wide AS rates among species, consistent with the drift barrier hypothesis. This pattern is dominated by low abundance isoforms, which represent the vast majority of the splice variant repertoire. We show that these low abundance isoforms are depleted in functional AS events, and most likely correspond to errors. Conversely, the AS rate of abundant isoforms, which are relatively enriched in functional AS events, tends to be lower in more complex species. All these observations are consistent with the hypothesis that variation in AS rates across metazoans reflects the limits set by drift on the capacity of selection to prevent gene expression errors.
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Affiliation(s)
- Florian Bénitière
- Laboratoire de Biometrie et Biologie Evolutive, CNRS, Universite Lyon 1, Villeurbanne, France
| | - Anamaria Necsulea
- Laboratoire de Biometrie et Biologie Evolutive, CNRS, Universite Lyon 1, Villeurbanne, France
| | - Laurent Duret
- Laboratoire de Biometrie et Biologie Evolutive, CNRS, Universite Lyon 1, Villeurbanne, France
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Li J, Li C, Xu W. Liver cancer-specific mutations in functional domains of ADAR2 lead to the elevation of coding and non-coding RNA editing in multiple tumor-related genes. Mol Genet Genomics 2024; 299:1. [PMID: 38170228 DOI: 10.1007/s00438-023-02091-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 10/17/2023] [Indexed: 01/05/2024]
Abstract
Mutation is the major cause of phenotypic innovations. Apart from DNA mutations, the alteration on RNA such as the ADAR-mediated A-to-I RNA editing could also shape the phenotype. These two layers of variations have not been systematically combined to study their collective roles in cancers. We collected the high-quality transcriptomes of ten hepatocellular carcinoma (HCC) and the matched control samples. We systematically identified HCC-specific mutations in the exonic regions and profiled the A-to-I RNA editome in each sample. All ten HCC samples had mutations in the CDS of ADAR2 gene (dsRNA-binding domain or catalytic domain). The consequence of these mutations converged to the elevation of ADAR2 efficiency as reflected by the global increase of RNA editing levels in HCC. The up-regulated editing sites (UES) were enriched in the CDS and UTR of oncogenes and tumor suppressor genes (TSG), indicating the possible roles of these target genes in HCC oncogenesis. We present the mutation-ADAR2-UES-oncogene/TSG-HCC axis that explains how mutations at different layers would finally lead to abnormal phenotype. In the light of central dogma, our work provides novel insights into how to fully take advantage of the transcriptome data to decipher the consequence of mutations.
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Affiliation(s)
- Jian Li
- Department of Molecular Imaging and Nuclear Medicine, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China
| | - Chaowei Li
- Department of PET/CT, The Second Clinical Medical College of Qingdao University (Qingdao Center Hospital), Qingdao, 266042, China
| | - Wengui Xu
- Department of Molecular Imaging and Nuclear Medicine, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China.
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7
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Xu Y, Liu J, Zhao T, Song F, Tian L, Cai W, Li H, Duan Y. Identification and Interpretation of A-to-I RNA Editing Events in Insect Transcriptomes. Int J Mol Sci 2023; 24:17126. [PMID: 38138955 PMCID: PMC10742984 DOI: 10.3390/ijms242417126] [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: 09/30/2023] [Revised: 12/01/2023] [Accepted: 12/03/2023] [Indexed: 12/24/2023] Open
Abstract
Adenosine-to-inosine (A-to-I) RNA editing is the most prevalent RNA modification in the nervous systems of metazoans. To study the biological significance of RNA editing, we first have to accurately identify these editing events from the transcriptome. The genome-wide identification of RNA editing sites remains a challenging task. In this review, we will first introduce the occurrence, regulation, and importance of A-to-I RNA editing and then describe the established bioinformatic procedures and difficulties in the accurate identification of these sit esespecially in small sized non-model insects. In brief, (1) to obtain an accurate profile of RNA editing sites, a transcriptome coupled with the DNA resequencing of a matched sample is favorable; (2) the single-cell sequencing technique is ready to be applied to RNA editing studies, but there are a few limitations to overcome; (3) during mapping and variant calling steps, various issues, like mapping and base quality, soft-clipping, and the positions of mismatches on reads, should be carefully considered; (4) Sanger sequencing of both RNA and the matched DNA is the best verification of RNA editing sites, but other auxiliary evidence, like the nonsynonymous-to-synonymous ratio or the linkage information, is also helpful for judging the reliability of editing sites. We have systematically reviewed the understanding of the biological significance of RNA editing and summarized the methodology for identifying such editing events. We also raised several promising aspects and challenges in this field. With insightful perspectives on both scientific and technical issues, our review will benefit the researchers in the broader RNA editing community.
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Affiliation(s)
| | | | | | | | | | | | | | - Yuange Duan
- MOA Key Lab of Pest Monitoring and Green Management, Department of Entomology, College of Plant Protection, China Agricultural University, Beijing 100193, China; (Y.X.); (J.L.); (T.Z.); (F.S.); (L.T.); (W.C.); (H.L.)
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8
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Voss G, Rosenthal JJC. High-level RNA editing diversifies the coleoid cephalopod brain proteome. Brief Funct Genomics 2023; 22:525-532. [PMID: 37981860 DOI: 10.1093/bfgp/elad034] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 07/20/2023] [Accepted: 07/25/2023] [Indexed: 11/21/2023] Open
Abstract
Coleoid cephalopods (octopus, squid and cuttlefish) have unusually complex nervous systems. The coleoid nervous system is also the only one currently known to recode the majority of expressed proteins through A-to-I RNA editing. The deamination of adenosine by adenosine deaminase acting on RNA (ADAR) enzymes produces inosine, which is interpreted as guanosine during translation. If this occurs in an open reading frame, which is the case for tens of thousands of editing sites in coleoids, it can recode the encoded protein. Here, we describe recent findings aimed at deciphering the mechanisms underlying high-level recoding and its adaptive potential. We describe the complement of ADAR enzymes in cephalopods, including a recently discovered novel domain in sqADAR1. We further summarize current evidence supporting an adaptive role of high-level RNA recoding in coleoids, and review recent studies showing that a large proportion of recoding sites is temperature-sensitive. Despite these new findings, the mechanisms governing the high level of RNA recoding in coleoid cephalopods remain poorly understood. Recent advances using genome editing in squid may provide useful tools to further study A-to-I RNA editing in these animals.
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Affiliation(s)
- Gjendine Voss
- The Eugene Bell Center, The Marine Biological Laboratory, 7 MBL Street, Woods Hole MA 02543, United States
| | - Joshua J C Rosenthal
- The Eugene Bell Center, The Marine Biological Laboratory, 7 MBL Street, Woods Hole MA 02543, United States
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9
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Zhang Y, Duan Y. Genome-Wide Analysis on Driver and Passenger RNA Editing Sites Suggests an Underestimation of Adaptive Signals in Insects. Genes (Basel) 2023; 14:1951. [PMID: 37895300 PMCID: PMC10606203 DOI: 10.3390/genes14101951] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
Adenosine-to-inosine (A-to-I) RNA editing leads to a similar effect to A-to-G mutations. RNA editing provides a temporo-spatial flexibility for organisms. Nonsynonymous (Nonsyn) RNA editing in insects is over-represented compared with synonymous (Syn) editing, suggesting adaptive signals of positive selection on Nonsyn editing during evolution. We utilized the brain RNA editome of Drosophila melanogaster to systematically study the LD (r2) between editing sites and infer its impact on the adaptive signals of RNA editing. Pairs of editing sites (PESs) were identified from the transcriptome. For CDS PESs of two consecutive editing sites, their occurrence was significantly biased to type-3 PES (Syn-Nonsyn). The haplotype frequency of type-3 PES exhibited a significantly higher abundance of AG than GA, indicating that the rear Nonsyn site is the driver that promotes the editing of the front Syn site (passenger). The exclusion of passenger Syn sites dramatically amplifies the adaptive signal of Nonsyn RNA editing. Our study for the first time quantitatively demonstrates that the linkage between RNA editing events comes from hitchhiking effects and leads to the underestimation of adaptive signals for Nonsyn editing. Our work provides novel insights for studying the evolutionary significance of RNA editing events.
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Affiliation(s)
| | - Yuange Duan
- MOA Key Lab of Pest Monitoring and Green Management, Department of Entomology, College of Plant Protection, China Agricultural University, Beijing 100193, China;
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10
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Lewin LE, Daniels KG, Hurst LD. Genes for highly abundant proteins in Escherichia coli avoid 5' codons that promote ribosomal initiation. PLoS Comput Biol 2023; 19:e1011581. [PMID: 37878567 PMCID: PMC10599525 DOI: 10.1371/journal.pcbi.1011581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 10/09/2023] [Indexed: 10/27/2023] Open
Abstract
In many species highly expressed genes (HEGs) over-employ the synonymous codons that match the more abundant iso-acceptor tRNAs. Bacterial transgene codon randomization experiments report, however, that enrichment with such "translationally optimal" codons has little to no effect on the resultant protein level. By contrast, consistent with the view that ribosomal initiation is rate limiting, synonymous codon usage following the 5' ATG greatly influences protein levels, at least in part by modifying RNA stability. For the design of bacterial transgenes, for simple codon based in silico inference of protein levels and for understanding selection on synonymous mutations, it would be valuable to computationally determine initiation optimality (IO) scores for codons for any given species. One attractive approach is to characterize the 5' codon enrichment of HEGs compared with the most lowly expressed genes, just as translational optimality scores of codons have been similarly defined employing the full gene body. Here we determine the viability of this approach employing a unique opportunity: for Escherichia coli there is both the most extensive protein abundance data for native genes and a unique large-scale transgene codon randomization experiment enabling objective definition of the 5' codons that cause, rather than just correlate with, high protein abundance (that we equate with initiation optimality, broadly defined). Surprisingly, the 5' ends of native genes that specify highly abundant proteins avoid such initiation optimal codons. We find that this is probably owing to conflicting selection pressures particular to native HEGs, including selection favouring low initiation rates, this potentially enabling high efficiency of ribosomal usage and low noise. While the classical HEG enrichment approach does not work, rendering simple prediction of native protein abundance from 5' codon content futile, we report evidence that initiation optimality scores derived from the transgene experiment may hold relevance for in silico transgene design for a broad spectrum of bacteria.
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Affiliation(s)
- Loveday E. Lewin
- The Milner Centre for Evolution, Department of Life Sciences, University of Bath, Bath, United Kingdom
| | - Kate G. Daniels
- The Milner Centre for Evolution, Department of Life Sciences, University of Bath, Bath, United Kingdom
| | - Laurence D. Hurst
- The Milner Centre for Evolution, Department of Life Sciences, University of Bath, Bath, United Kingdom
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11
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Ge F, Cao X, Jiang Y. A-to-I RNA editing shows dramatic up-regulation in osteosarcoma and broadly regulates tumor-related genes by altering microRNA target regions. J Appl Genet 2023; 64:493-505. [PMID: 37542613 DOI: 10.1007/s13353-023-00777-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 07/28/2023] [Accepted: 08/01/2023] [Indexed: 08/07/2023]
Abstract
A-to-I RNA editing is a prevalent type of RNA modification in animals. The dysregulation of RNA editing has led to multiple human cancers. However, the role of RNA editing has never been studied in osteosarcoma, a complex bone cancer with unknown molecular basis. We retrieved the RNA-sequencing data from 24 primary osteosarcoma patients and 3 healthy controls. We systematically profiled the RNA editomes in these samples and quantitatively identified reliable differential editing sites (DES) between osteosarcoma and normal samples. RNA editing efficiency is dramatically increased in osteosarcoma, presumably due to the significant up-regulation of editing enzymes ADAR1 and ADAR2. Up-regulated DES in osteosarcoma are enriched in 3'UTRs. Strikingly, such 3'UTR sites are further enriched in microRNA binding regions of gene EMP2 and other oncogenes, abolishing the microRNA suppression on target genes. Accordingly, the expression of these tumor-promoting genes is elevated in osteosarcoma. There might be an RNA editing-dependent pathway leading to osteosarcoma. We expanded our knowledge on the potential roles of RNA editing in oncogenesis. Based on these molecular features, our work is valuable for future prognosis and diagnosis of osteosarcoma.
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Affiliation(s)
- Fuqun Ge
- Department of Joint Surgery, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China
| | - Xinyue Cao
- School of Clinical Medicine, Qilu Medical University, Zibo, 255300, Shandong, China
| | - Yankai Jiang
- Department of Joint Surgery, The Second Hospital of Shandong University, Jinan, 250033, Shandong, China.
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12
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Birk MA, Liscovitch-Brauer N, Dominguez MJ, McNeme S, Yue Y, Hoff JD, Twersky I, Verhey KJ, Sutton RB, Eisenberg E, Rosenthal JJC. Temperature-dependent RNA editing in octopus extensively recodes the neural proteome. Cell 2023; 186:2544-2555.e13. [PMID: 37295402 PMCID: PMC10445230 DOI: 10.1016/j.cell.2023.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/24/2023] [Accepted: 05/04/2023] [Indexed: 06/12/2023]
Abstract
In poikilotherms, temperature changes challenge the integration of physiological function. Within the complex nervous systems of the behaviorally sophisticated coleoid cephalopods, these problems are substantial. RNA editing by adenosine deamination is a well-positioned mechanism for environmental acclimation. We report that the neural proteome of Octopus bimaculoides undergoes massive reconfigurations via RNA editing following a temperature challenge. Over 13,000 codons are affected, and many alter proteins that are vital for neural processes. For two highly temperature-sensitive examples, recoding tunes protein function. For synaptotagmin, a key component of Ca2+-dependent neurotransmitter release, crystal structures and supporting experiments show that editing alters Ca2+ binding. For kinesin-1, a motor protein driving axonal transport, editing regulates transport velocity down microtubules. Seasonal sampling of wild-caught specimens indicates that temperature-dependent editing occurs in the field as well. These data show that A-to-I editing tunes neurophysiological function in response to temperature in octopus and most likely other coleoids.
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Affiliation(s)
- Matthew A Birk
- Bell Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Biology, Saint Francis University, Loretto, PA 15940, USA
| | | | - Matthew J Dominguez
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX 79410, USA
| | - Sean McNeme
- Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Yang Yue
- Department of Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - J Damon Hoff
- Department of Biophysics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Itamar Twersky
- The Nano Center, The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Kristen J Verhey
- Department of Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - R Bryan Sutton
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX 79410, USA
| | - Eli Eisenberg
- School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel.
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13
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Duan Y, Li H, Cai W. Adaptation of A-to-I RNA editing in bacteria, fungi, and animals. Front Microbiol 2023; 14:1204080. [PMID: 37293227 PMCID: PMC10244538 DOI: 10.3389/fmicb.2023.1204080] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 05/09/2023] [Indexed: 06/10/2023] Open
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14
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Lewis Z. Expanding the proteome: A-to-I RNA editing provides an adaptive advantage. Proc Natl Acad Sci U S A 2023; 120:e2303563120. [PMID: 37036963 PMCID: PMC10120046 DOI: 10.1073/pnas.2303563120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023] Open
Affiliation(s)
- Zachary A. Lewis
- Department of Microbiology, University of Georgia, Athens, GA30602
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15
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Xin K, Zhang Y, Fan L, Qi Z, Feng C, Wang Q, Jiang C, Xu JR, Liu H. Experimental evidence for the functional importance and adaptive advantage of A-to-I RNA editing in fungi. Proc Natl Acad Sci U S A 2023; 120:e2219029120. [PMID: 36917661 PMCID: PMC10041177 DOI: 10.1073/pnas.2219029120] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 02/13/2023] [Indexed: 03/16/2023] Open
Abstract
Adenosine-to-inosine (A-to-I) editing is the most prevalent type of RNA editing in animals, and it occurs in fungi specifically during sexual reproduction. However, it is debatable whether A-to-I RNA editing is adaptive. Deciphering the functional importance of individual editing sites is essential for the mechanistic understanding of the adaptive advantages of RNA editing. Here, by performing gene deletion for 17 genes with conserved missense editing (CME) sites and engineering underedited (ue) and overedited (oe) mutants for 10 CME sites using site-specific mutagenesis at the native locus in Fusarium graminearum, we demonstrated that two CME sites in CME5 and CME11 genes are functionally important for sexual reproduction. Although the overedited mutant was normal in sexual reproduction, the underedited mutant of CME5 had severe defects in ascus and ascospore formation like the deletion mutant, suggesting that the CME site of CME5 is co-opted for sexual development. The preediting residue of Cme5 is evolutionarily conserved across diverse classes of Ascomycota, while the postediting one is rarely hardwired into the genome, implying that editing at this site leads to higher fitness than a genomic A-to-G mutation. More importantly, mutants expressing only the underedited or the overedited allele of CME11 are defective in ascosporogenesis, while those expressing both alleles displayed normal phenotypes, indicating that concurrently expressing edited and unedited versions of Cme11 is more advantageous than either. Our study provides convincing experimental evidence for the long-suspected adaptive advantages of RNA editing in fungi and likely in animals.
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Affiliation(s)
- Kaiyun Xin
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang, Shaanxi712100, China
| | - Yang Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang, Shaanxi712100, China
| | - Ligang Fan
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang, Shaanxi712100, China
| | - Zhaomei Qi
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang, Shaanxi712100, China
| | - Chanjing Feng
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang, Shaanxi712100, China
| | - Qinhu Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang, Shaanxi712100, China
| | - Cong Jiang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang, Shaanxi712100, China
| | - Jin-Rong Xu
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN47907
| | - Huiquan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang, Shaanxi712100, China
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16
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Evolutionary honing in and mutational replacement: how long-term directed mutational responses to specific environmental pressures are possible. Theory Biosci 2023; 142:87-105. [PMID: 36899155 DOI: 10.1007/s12064-023-00387-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/13/2023] [Indexed: 03/12/2023]
Abstract
Recent results have shown that the human malaria-resistant hemoglobin S mutation originates de novo more frequently in the gene and in the population where it is of adaptive significance, namely, in the hemoglobin subunit beta gene compared to the nonresistant but otherwise identical 20A[Formula: see text]T mutation in the hemoglobin subunit delta gene, and in sub-Saharan Africans, who have been subject to intense malarial pressure for many generations, compared to northern Europeans, who have not. This finding raises a fundamental challenge to the traditional notion of accidental mutation. Here, we address this finding with the replacement hypothesis, according to which preexisting genetic interactions can lead directly and mechanistically to mutations that simplify and replace them. Thus, an evolutionary process under selection can gradually hone in on interactions of importance for the currently evolving adaptations, from which large-effect mutations follow that are relevant to these adaptations. We exemplify this hypothesis using multiple types of mutation, including gene fusion mutations, gene duplication mutations, A[Formula: see text]G mutations in RNA-edited sites and transcription-associated mutations, and place it in the broader context of a system-level view of mutation origination called interaction-based evolution. Potential consequences include that similarity of mutation pressures may contribute to parallel evolution in genetically related species, that the evolution of genome organization may be driven by mutational mechanisms, that transposable element movements may also be explained by replacement, and that long-term directed mutational responses to specific environmental pressures are possible. Such mutational phenomena need to be further tested by future studies in natural and artificial settings.
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17
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Zhang P, Zhu Y, Guo Q, Li J, Zhan X, Yu H, Xie N, Tan H, Lundholm N, Garcia-Cuetos L, Martin MD, Subirats MA, Su YH, Ruiz-Trillo I, Martindale MQ, Yu JK, Gilbert MTP, Zhang G, Li Q. On the origin and evolution of RNA editing in metazoans. Cell Rep 2023; 42:112112. [PMID: 36795564 PMCID: PMC9989829 DOI: 10.1016/j.celrep.2023.112112] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 11/28/2022] [Accepted: 01/30/2023] [Indexed: 02/16/2023] Open
Abstract
Extensive adenosine-to-inosine (A-to-I) editing of nuclear-transcribed mRNAs is the hallmark of metazoan transcriptional regulation. Here, by profiling the RNA editomes of 22 species that cover major groups of Holozoa, we provide substantial evidence supporting A-to-I mRNA editing as a regulatory innovation originating in the last common ancestor of extant metazoans. This ancient biochemistry process is preserved in most extant metazoan phyla and primarily targets endogenous double-stranded RNA (dsRNA) formed by evolutionarily young repeats. We also find intermolecular pairing of sense-antisense transcripts as an important mechanism for forming dsRNA substrates for A-to-I editing in some but not all lineages. Likewise, recoding editing is rarely shared across lineages but preferentially targets genes involved in neural and cytoskeleton systems in bilaterians. We conclude that metazoan A-to-I editing might first emerge as a safeguard mechanism against repeat-derived dsRNA and was later co-opted into diverse biological processes due to its mutagenic nature.
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Affiliation(s)
- Pei Zhang
- BGI-Shenzhen, Shenzhen 518083, China; Section for Ecology and Evolution, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
| | | | - Qunfei Guo
- BGI-Shenzhen, Shenzhen 518083, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ji Li
- BGI Research-Wuhan, BGI, Wuhan 430074, China
| | | | - Hao Yu
- BGI-Shenzhen, Shenzhen 518083, China
| | - Nianxia Xie
- BGI-Shenzhen, Shenzhen 518083, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | | | - Nina Lundholm
- Natural History Museum of Denmark, University of Copenhagen, 1353 Copenhagen, Denmark
| | - Lydia Garcia-Cuetos
- Natural History Museum of Denmark, University of Copenhagen, 1353 Copenhagen, Denmark
| | - Michael D Martin
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; Center for Theoretical Evolutionary Genomics, Department of Integrative Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | | | - Yi-Hsien Su
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Iñaki Ruiz-Trillo
- Institute of Evolutionary Biology, UPF-CSIC Barcelona, 08003 Barcelona, Spain; ICREA, Passeig Lluís Companys 23, 08010 Barcelona, Catalonia, Spain; Departament de Genètica, Microbiologia i Estadística, Facultat de Bilogia, Universitat de Barcelona (UB), 08028 Barcelona, Spain
| | - Mark Q Martindale
- The Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL 32080, USA
| | - Jr-Kai Yu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan; Marine Research Station, Institute of Cellular and Organismic Biology, Academia Sinica, Yilan 26242, Taiwan
| | - M Thomas P Gilbert
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; Center for Evolutionary Hologenomics, The GLOBE Institute, University of Copenhagen, 1353 Copenhagen, Denmark
| | - Guojie Zhang
- Center of Evolutionary and Organismal Biology, & Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China; Liangzhu Laboratory, Zhejiang University Medical Center, 1369 West Wenyi Road, Hangzhou 311121, China; State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China; Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark.
| | - Qiye Li
- BGI-Shenzhen, Shenzhen 518083, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
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18
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Duan Y, Cai W, Li H. Chloroplast C-to-U RNA editing in vascular plants is adaptive due to its restorative effect: testing the restorative hypothesis. RNA (NEW YORK, N.Y.) 2023; 29:141-152. [PMID: 36649983 PMCID: PMC9891260 DOI: 10.1261/rna.079450.122] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 10/30/2022] [Indexed: 06/10/2023]
Abstract
The adaptiveness of nonsynonymous RNA editing (recoding) could be conferred by the flexibility of the temporal-spatially controllable proteomic diversity, or by its restorative effect which fixes unfavorable genomic mutations at the RNA level. These two complementary hypotheses, namely, the diversifying hypothesis and the restorative hypothesis, have distinct predictions on the landscape of RNA editing sites. We collected the chloroplast C-to-U RNA editomes of 21 vascular plants (11 angiosperms, four gymnosperms, and six ferns) from a previous study, aiming to testify whether the plant editomes typically conform to the restorative hypothesis. All predictions made by the restorative hypothesis are verified: (i) nonsynonymous editing sites are more frequent and have higher editing levels than synonymous sites; (ii) nonsynonymous editing levels are extremely high and show weak tissue-specificity in plants; (iii) on the inferred genomic sites with recent T-to-C mutations, nonsynonymous sites but not synonymous sites are compensated by C-to-U RNA editing. In conclusion, nonsynonymous C-to-U RNA editing in plants is adaptive due to its restorative effects. The recoding levels are high and are constantly required across the whole plant so that the recoding events could perfectly mimic DNA mutations. The evolutionary significance of plant RNA editing is systematically demonstrated at the genome-wide level.
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Affiliation(s)
- Yuange Duan
- Key Laboratory of Pest Monitoring and Green Management, Department of Entomology, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Wanzhi Cai
- Key Laboratory of Pest Monitoring and Green Management, Department of Entomology, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Hu Li
- Key Laboratory of Pest Monitoring and Green Management, Department of Entomology, College of Plant Protection, China Agricultural University, Beijing 100193, China
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19
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Zhang J, Xu C. Gene product diversity: adaptive or not? Trends Genet 2022; 38:1112-1122. [PMID: 35641344 PMCID: PMC9560964 DOI: 10.1016/j.tig.2022.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 04/30/2022] [Accepted: 05/03/2022] [Indexed: 01/24/2023]
Abstract
One gene does not equal one RNA or protein. The genomic revolution has revealed numerous different RNA and protein molecules that can be produced from one gene, such as circular RNAs generated by back-splicing, proteins with residues mismatching the genomic encoding because of RNA editing, and proteins extended in the C terminus via stop codon readthrough in translation. Are these diverse products results of exquisite gene regulations or imprecise biological processes? While there are cases where the gene product diversity appears beneficial, genome-scale patterns suggest that much of this diversity arises from nonadaptive, molecular errors. This finding has important implications for studying the functions of diverse gene products and for understanding the fundamental properties and evolution of cellular life.
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Affiliation(s)
- Jianzhi Zhang
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Chuan Xu
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China
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20
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Loss of Ca V1.3 RNA editing enhances mouse hippocampal plasticity, learning, and memory. Proc Natl Acad Sci U S A 2022; 119:e2203883119. [PMID: 35914168 PMCID: PMC9371748 DOI: 10.1073/pnas.2203883119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
L-type CaV1.3 calcium channels are expressed on the dendrites and soma of neurons, and there is a paucity of information about its role in hippocampal plasticity. Here, by genetic targeting to ablate CaV1.3 RNA editing, we demonstrate that unedited CaV1.3ΔECS mice exhibited improved learning and enhanced long-term memory, supporting a functional role of RNA editing in behavior. Significantly, the editing paradox that functional recoding of CaV1.3 RNA editing sites slows Ca2+-dependent inactivation to increase Ca2+ influx but reduces channel open probability to decrease Ca2+ influx was resolved. Mechanistically, using hippocampal slice recordings, we provide evidence that unedited CaV1.3 channels permitted larger Ca2+ influx into the hippocampal pyramidal neurons to bolster neuronal excitability, synaptic transmission, late long-term potentiation, and increased dendritic arborization. Of note, RNA editing of the CaV1.3 IQ-domain was found to be evolutionarily conserved in mammals, which lends support to the importance of the functional recoding of the CaV1.3 channel in brain function.
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21
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Wright CJ, Smith CWJ, Jiggins CD. Alternative splicing as a source of phenotypic diversity. Nat Rev Genet 2022; 23:697-710. [PMID: 35821097 DOI: 10.1038/s41576-022-00514-4] [Citation(s) in RCA: 111] [Impact Index Per Article: 55.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2022] [Indexed: 12/27/2022]
Abstract
A major goal of evolutionary genetics is to understand the genetic processes that give rise to phenotypic diversity in multicellular organisms. Alternative splicing generates multiple transcripts from a single gene, enriching the diversity of proteins and phenotypic traits. It is well established that alternative splicing contributes to key innovations over long evolutionary timescales, such as brain development in bilaterians. However, recent developments in long-read sequencing and the generation of high-quality genome assemblies for diverse organisms has facilitated comparisons of splicing profiles between closely related species, providing insights into how alternative splicing evolves over shorter timescales. Although most splicing variants are probably non-functional, alternative splicing is nonetheless emerging as a dynamic, evolutionarily labile process that can facilitate adaptation and contribute to species divergence.
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Affiliation(s)
- Charlotte J Wright
- Tree of Life, Wellcome Sanger Institute, Cambridge, UK. .,Department of Zoology, University of Cambridge, Cambridge, UK.
| | | | - Chris D Jiggins
- Department of Zoology, University of Cambridge, Cambridge, UK.
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22
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Interplay between A-to-I Editing and Splicing of RNA: A Potential Point of Application for Cancer Therapy. Int J Mol Sci 2022; 23:ijms23095240. [PMID: 35563631 PMCID: PMC9105294 DOI: 10.3390/ijms23095240] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 11/17/2022] Open
Abstract
Adenosine-to-inosine RNA editing is a system of post-transcriptional modification widely distributed in metazoans which is catalyzed by ADAR enzymes and occurs mostly in double-stranded RNA (dsRNA) before splicing. This type of RNA editing changes the genetic code, as inosine generally pairs with cytosine in contrast to adenosine, and this expectably modulates RNA splicing. We review the interconnections between RNA editing and splicing in the context of human cancer. The editing of transcripts may have various effects on splicing, and resultant alternatively spliced isoforms may be either tumor-suppressive or oncogenic. Dysregulated RNA splicing in cancer often causes the release of excess amounts of dsRNA into cytosol, where specific dsRNA sensors provoke antiviral-like responses, including type I interferon signaling. These responses may arrest cell division, causing apoptosis and, externally, stimulate antitumor immunity. Thus, small-molecule spliceosome inhibitors have been shown to facilitate the antiviral-like signaling and are considered to be potential cancer therapies. In turn, a cytoplasmic isoform of ADAR can deaminate dsRNA in cytosol, thereby decreasing its levels and diminishing antitumor innate immunity. We propose that complete or partial inhibition of ADAR may enhance the proapoptotic and cytotoxic effects of splicing inhibitors and that it may be considered a promising addition to cancer therapies targeting RNA splicing.
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23
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A-to-I RNA editing of BLCAP promotes cell proliferation by losing the inhibitory of Rb1 in colorectal cancer. Exp Cell Res 2022; 417:113209. [DOI: 10.1016/j.yexcr.2022.113209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/03/2022] [Accepted: 05/14/2022] [Indexed: 11/23/2022]
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24
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Gabay O, Shoshan Y, Kopel E, Ben-Zvi U, Mann TD, Bressler N, Cohen-Fultheim R, Schaffer AA, Roth SH, Tzur Z, Levanon EY, Eisenberg E. Landscape of adenosine-to-inosine RNA recoding across human tissues. Nat Commun 2022; 13:1184. [PMID: 35246538 PMCID: PMC8897444 DOI: 10.1038/s41467-022-28841-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 01/27/2022] [Indexed: 12/18/2022] Open
Abstract
RNA editing by adenosine deaminases changes the information encoded in the mRNA from its genomic blueprint. Editing of protein-coding sequences can introduce novel, functionally distinct, protein isoforms and diversify the proteome. The functional importance of a few recoding sites has been appreciated for decades. However, systematic methods to uncover these sites perform poorly, and the full repertoire of recoding in human and other mammals is unknown. Here we present a new detection approach, and analyze 9125 GTEx RNA-seq samples, to produce a highly-accurate atlas of 1517 editing sites within the coding region and their editing levels across human tissues. Single-cell RNA-seq data shows protein recoding contributes to the variability across cell subpopulations. Most highly edited sites are evolutionary conserved in non-primate mammals, attesting for adaptation. This comprehensive set can facilitate understanding of the role of recoding in human physiology and diseases. Gabay et al. provide a highly-accurate atlas of recoding by A-to-I RNA editing in human, profiled across tissues and cell subpopulations. Most highly edited sites are evolutionary conserved in non-primate mammals, attesting for adaptation.
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Affiliation(s)
- Orshay Gabay
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Yoav Shoshan
- Raymond and Beverly Sackler School of Physics and Astronomy and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Eli Kopel
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Udi Ben-Zvi
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Tomer D Mann
- Tel Aviv Sourasky Medical Center and Sackler school of medicine, Tel Aviv University, Tel Aviv, Israel
| | - Noam Bressler
- Raymond and Beverly Sackler School of Physics and Astronomy and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Roni Cohen-Fultheim
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Amos A Schaffer
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Shalom Hillel Roth
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Ziv Tzur
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Erez Y Levanon
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel. .,The Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, 5290002, Israel.
| | - Eli Eisenberg
- Raymond and Beverly Sackler School of Physics and Astronomy and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel.
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25
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Moldovan MA, Chervontseva ZS, Nogina DS, Gelfand MS. A hierarchy in clusters of cephalopod mRNA editing sites. Sci Rep 2022; 12:3447. [PMID: 35236910 PMCID: PMC8891338 DOI: 10.1038/s41598-022-07460-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 02/07/2022] [Indexed: 11/09/2022] Open
Abstract
RNA editing in the form of substituting adenine with inosine (A-to-I editing) is the most frequent type of RNA editing in many metazoan species. In most species, A-to-I editing sites tend to form clusters and editing at clustered sites depends on editing of the adjacent sites. Although functionally important in some specific cases, A-to-I editing usually is rare. The exception occurs in soft-bodied coleoid cephalopods, where tens of thousands of potentially important A-to-I editing sites have been identified, making coleoids an ideal model for studying of properties and evolution of A-to-I editing sites. Here, we apply several diverse techniques to demonstrate a strong tendency of coleoid RNA editing sites to cluster along the transcript. We show that clustering of editing sites and correlated editing substantially contribute to the transcriptome diversity that arises due to extensive RNA editing. Moreover, we identify three distinct types of editing site clusters, varying in size, and describe RNA structural features and mechanisms likely underlying formation of these clusters. In particular, these observations may explain sequence conservation at large distances around editing sites and the observed dependency of editing on mutations in the vicinity of editing sites.
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Affiliation(s)
- Mikhail A Moldovan
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow, Russia, 121205.
| | - Zoe S Chervontseva
- A.A.Kharkevich Institute for Information Transmission Problems (RAS), Bolshoy Karetny Per. 19, bld.1, Moscow, Russia, 127051
| | - Daria S Nogina
- A.A.Kharkevich Institute for Information Transmission Problems (RAS), Bolshoy Karetny Per. 19, bld.1, Moscow, Russia, 127051.,Faculty of Bioengineering and Bioinformatics, M.V. Lomonosov Moscow State University, Leninskie Gory 1, Moscow, Russia, 119991
| | - Mikhail S Gelfand
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow, Russia, 121205.,A.A.Kharkevich Institute for Information Transmission Problems (RAS), Bolshoy Karetny Per. 19, bld.1, Moscow, Russia, 127051
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26
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Poor evidence for host-dependent regular RNA editing in the transcriptome of SARS-CoV-2. J Appl Genet 2022; 63:413-421. [PMID: 35179717 PMCID: PMC8854479 DOI: 10.1007/s13353-022-00687-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/21/2021] [Accepted: 02/13/2022] [Indexed: 12/18/2022]
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27
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Ru FX, Kong F, Ren CY, He YS, Xia SY, Li YN, Liang YP, Feng JJ, Wei ZY, Chen JH. Repeated Winning and Losing Experiences in Chronic Social Conflicts Are Linked to RNA Editing Pattern Difference. Front Psychiatry 2022; 13:896794. [PMID: 35664469 PMCID: PMC9161819 DOI: 10.3389/fpsyt.2022.896794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 04/25/2022] [Indexed: 02/05/2023] Open
Abstract
Winner-loser effects influence subsequent agonistic interactions between conspecifics. Previous winning experiences could strengthen future aggression and increase the chance of winning the next agonistic interaction, while previous losing experiences could have the opposite effect. Although the role of A-to-I RNA editing has been recently implicated in chronic social defeat stress and aggressive behavior, it remains to be further elucidated in chronic social conflicts in agonistic interactions, especially in the repeated aggression (winners) and repeated defeat (losers) resulted from these conflicts. In the current study, transcriptome-wide A-to-I RNA editing in the dorsal striatum was investigated in a mouse model of chronic social conflicts, and compared between mice repeatedly winning and losing daily agonistic interactions. Our analysis identified 622 A-to-I RNA editing sites in the mouse dorsal striatum, with 23 to be differentially edited in 22 genes, most of which had been previously associated with neurological, psychiatric, or immune disorders. Among these differential RNA editing (DRE) sites four missense variants were observed in neuroligin 2 (Nlgn2), Cdc42 guanine nucleotide exchange factor 9 (Arhgef9) BLCAP apoptosis inducing factor (Blcap), and cytoplasmic FMR1 interacting protein 2 (Cyfip2), as well as two noncoding RNA sites in small nucleolar RNA host gene 11 (Snhg11) and the maternally expressed 3 (Meg3) gene. Moreover, significant changes were observed in gene functions and pathways enriched by genes with A-to-I RNA editing in losers and especially winners compared to controls. Our results demonstrate that repeated winning and losing experiences in chronic social conflicts are linked to A-to-I RNA editing pattern difference, underlining its role in the molecular mechanism of agonistic interactions between conspecifics.
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Affiliation(s)
- Fu-Xia Ru
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
| | - Fanzhi Kong
- Shantou University Mental Health Center, Shantou University Medical College, Shantou, China
| | - Chun-Yan Ren
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
| | - Yu-Shan He
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
| | - Shou-Yue Xia
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
| | - Yu-Ning Li
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
| | - Ya-Ping Liang
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
| | - Jun-Jie Feng
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
| | - Zhi-Yuan Wei
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
| | - Jian-Huan Chen
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
- Joint Primate Research Center for Chronic Diseases, Institute of Zoology of Guangdong Academy of Science, Jiangnan University, Wuxi, China
- Jiangnan University Brain Institute, Wuxi, China
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28
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Zhang Y, Jiang W, Li Y, Jin X, Yang X, Zhang P, Jiang W, Yin B. Fast evolution of SARS-CoV-2 driven by deamination systems in hosts. Future Virol 2021; 16:587-590. [PMID: 34721652 DOI: 10.2217/fvl-2021-0181] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 08/25/2021] [Indexed: 11/21/2022]
Abstract
As an RNA virus, the fast evolution of SARS-CoV-2 is driven by the extensive RNA deamination by the host cells.
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Affiliation(s)
- Yanping Zhang
- Department of Respiratory Diseases, Qingdao Haici Hospital, Shandong, China.,The Affiliated Qingdao Hiser Hospital of Qingdao University, Qingdao, Shandong, China
| | - Wen Jiang
- Department of Respiratory Diseases, Qingdao Haici Hospital, Shandong, China.,The Affiliated Qingdao Hiser Hospital of Qingdao University, Qingdao, Shandong, China
| | - Yan Li
- Department of Cardiology, Qingdao Center Hospital, Shandong, China
| | - Xiaojie Jin
- Department of Respiratory Diseases, Qingdao Haici Hospital, Shandong, China.,The Affiliated Qingdao Hiser Hospital of Qingdao University, Qingdao, Shandong, China
| | - Xiaoping Yang
- Department of Respiratory Diseases, Qingdao Haici Hospital, Shandong, China.,The Affiliated Qingdao Hiser Hospital of Qingdao University, Qingdao, Shandong, China
| | - Pirun Zhang
- College of Basic Medicine, Shandong University of Traditional Chinese Medicine, Shandong, China
| | - Wenqing Jiang
- Department of Respiratory Diseases, Qingdao Haici Hospital, Shandong, China.,The Affiliated Qingdao Hiser Hospital of Qingdao University, Qingdao, Shandong, China
| | - Bin Yin
- Department of Respiratory Diseases, Qingdao Haici Hospital, Shandong, China.,The Affiliated Qingdao Hiser Hospital of Qingdao University, Qingdao, Shandong, China
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29
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Shoshan Y, Liscovitch-Brauer N, Rosenthal JJC, Eisenberg E. Adaptive Proteome Diversification by Nonsynonymous A-to-I RNA Editing in Coleoid Cephalopods. Mol Biol Evol 2021; 38:3775-3788. [PMID: 34022057 PMCID: PMC8382921 DOI: 10.1093/molbev/msab154] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
RNA editing by the ADAR enzymes converts selected adenosines into inosines, biological mimics for guanosines. By doing so, it alters protein-coding sequences, resulting in novel protein products that diversify the proteome beyond its genomic blueprint. Recoding is exceptionally abundant in the neural tissues of coleoid cephalopods (octopuses, squids, and cuttlefishes), with an over-representation of nonsynonymous edits suggesting positive selection. However, the extent to which proteome diversification by recoding provides an adaptive advantage is not known. It was recently suggested that the role of evolutionarily conserved edits is to compensate for harmful genomic substitutions, and that there is no added value in having an editable codon as compared with a restoration of the preferred genomic allele. Here, we show that this hypothesis fails to explain the evolutionary dynamics of recoding sites in coleoids. Instead, our results indicate that a large fraction of the shared, strongly recoded, sites in coleoids have been selected for proteome diversification, meaning that the fitness of an editable A is higher than an uneditable A or a genomically encoded G.
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Affiliation(s)
- Yoav Shoshan
- Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
| | - Noa Liscovitch-Brauer
- Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
| | | | - Eli Eisenberg
- Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
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30
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Xu C, Zhang J. Mammalian circular RNAs result largely from splicing errors. Cell Rep 2021; 36:109439. [PMID: 34320353 PMCID: PMC8365531 DOI: 10.1016/j.celrep.2021.109439] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 04/13/2021] [Accepted: 07/02/2021] [Indexed: 12/20/2022] Open
Abstract
Ubiquitous in eukaryotes, circular RNAs (circRNAs) comprise a large class of mostly non-coding RNAs produced by back-splicing. Although some circRNAs have demonstrated biochemical activities, whether most circRNAs are functional is unknown. Here, we test the hypothesis that circRNA production primarily results from splicing error and so is deleterious instead of beneficial. In support of the error hypothesis, our analysis of RNA sequencing data from 11 shared tissues of humans, macaques, and mice finds that (1) back-splicing is much rarer than linear-splicing, (2) the rate of back-splicing diminishes with the splicing amount, (3) the overall prevalence of back-splicing in a species declines with its effective population size, and (4) circRNAs are overall evolutionarily unconserved. We estimate that more than 97% of the observed circRNA production is deleterious. We identify a small number of functional circRNA candidates, and the genome-wide trend strongly suggests that circRNAs are largely non-functional products of splicing errors.
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Affiliation(s)
- Chuan Xu
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China; Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Jianzhi Zhang
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan 48109, USA.
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31
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Huang J, Lin L, Dong Z, Yang L, Zheng T, Gu W, Zhang Y, Yin T, Sjöstedt E, Mulder J, Uhlén M, Kristiansen K, Bolund L, Luo Y. A porcine brain-wide RNA editing landscape. Commun Biol 2021; 4:717. [PMID: 34112917 PMCID: PMC8192503 DOI: 10.1038/s42003-021-02238-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 05/18/2021] [Indexed: 11/12/2022] Open
Abstract
Adenosine-to-inosine (A-to-I) RNA editing, catalyzed by ADAR enzymes, is an essential post-transcriptional modification. Although hundreds of thousands of RNA editing sites have been reported in mammals, brain-wide analysis of the RNA editing in the mammalian brain remains rare. Here, a genome-wide RNA-editing investigation is performed in 119 samples, representing 30 anatomically defined subregions in the pig brain. We identify a total of 682,037 A-to-I RNA editing sites of which 97% are not identified before. Within the pig brain, cerebellum and olfactory bulb are regions with most edited transcripts. The editing level of sites residing in protein-coding regions are similar across brain regions, whereas region-distinct editing is observed in repetitive sequences. Highly edited conserved recoding events in pig and human brain are found in neurotransmitter receptors, demonstrating the evolutionary importance of RNA editing in neurotransmission functions. Although potential data biases caused by age, sex or health status are not considered, this study provides a rich resource to better understand the evolutionary importance of post-transcriptional RNA editing.
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Affiliation(s)
- Jinrong Huang
- Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, BGI-Shenzhen, Shenzhen, China.
- Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
| | - Lin Lin
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Zhanying Dong
- Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, BGI-Shenzhen, Shenzhen, China
| | - Ling Yang
- Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, BGI-Shenzhen, Shenzhen, China
| | - Tianyu Zheng
- Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, BGI-Shenzhen, Shenzhen, China
| | - Weiwang Gu
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, China
| | - Yan Zhang
- Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Tailang Yin
- Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Evelina Sjöstedt
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Science for Life Laboratory, Department of Protein Science, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Jan Mulder
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Mathias Uhlén
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Science for Life Laboratory, Department of Protein Science, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Karsten Kristiansen
- Laboratory of Genomics and Molecular Biomedicine, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Lars Bolund
- Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, BGI-Shenzhen, Shenzhen, China
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Yonglun Luo
- Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, BGI-Shenzhen, Shenzhen, China.
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark.
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32
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Li J, Li Q, Yu CP, Chang S, Xie LL, Wang S. Genome-wide expression changes mediated by A-to-I RNA editing correlate with hepatic oncogenesis. Transl Cancer Res 2021; 10:2725-2737. [PMID: 35116583 PMCID: PMC8798912 DOI: 10.21037/tcr-21-236] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 05/06/2021] [Indexed: 12/31/2022]
Abstract
Background Adenosine-to-inosine (A-to-I) RNA editing is one of the most prevalent RNA modifications in the animal kingdom. Since inosine is recognized as guanosines, the A-to-I process mimics A-to-G DNA mutations but can be controlled in a more flexible manner compared to DNA alterations. Methods We parsed the transcriptomes and translatomes of liver cancer and normal tissues from ten patients. We profiled the landscape of the A-to-I RNA editome in these samples and interrogated whether the A-to-I processes participated in the gene expression regulation in oncogenesis. Results Globally, editing activity was enhanced in all tumor samples compared to that in normal samples. Accordingly, expression of the gene encoding the RNA editing enzyme ADAR (adenosine deaminase acting on RNA) was elevated. Two intronic self-editing sites in ADAR mRNAs controlled its splicing pattern and may regulate its translation efficiency (TE). Moreover, the expression of oncogenes was generally upregulated in tumors, whereas tumor suppressor genes (TSG) were downregulated, possibly due to alterations to microRNA binding sites or RNA splicing defects caused by A-to-I editing. Conclusions A-to-I RNA editing plays a crucial role in the oncogenesis of liver cancer. ADAR regulates its own expression via self-editing, and it also affects global transcriptomes and translatomes involving cancer-related genes by RNA editing and changing their expression patterns.
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Affiliation(s)
- Jian Li
- Department of Interventional Radiology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Qun Li
- Department of Interventional Radiology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Chun-Peng Yu
- Department of Interventional Radiology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Shuai Chang
- Department of Interventional Radiology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Ling-Ling Xie
- Department of Interventional Radiology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Song Wang
- Department of Interventional Radiology, The Affiliated Hospital of Qingdao University, Qingdao, China
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33
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Duan Y, Tang X, Lu J. Evolutionary driving forces of A-to-I editing in metazoans. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 13:e1666. [PMID: 33998151 DOI: 10.1002/wrna.1666] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 04/12/2021] [Accepted: 04/24/2021] [Indexed: 11/05/2022]
Abstract
Adenosine-to-inosine (A-to-I) RNA editing is an evolutionarily conserved mechanism that converts adenosines to inosines in metazoans' transcriptomes. However, the landscapes of editomes have considerably changed during evolution. Here, we review some of our current knowledge of A-to-I editing in the metazoan transcriptomes, focusing on the possible evolutionary driving forces underlying the editing events. First, we review the evolution of ADAR gene family in animals. Then, we summarize the recent advances in characterizing the editomes of various metazoan species. Next, we highlight several factors contributing to the interspecies differences in editomes, including variations in copy number and expression patterns of ADAR genes, the differences in genomic architectures and contents, and the differences in the efficacy of natural selection. After that, we review the possible diversifying and restorative effects of the editing (recoding) events that change the protein sequences. Finally, we discuss the possible convergent evolution of RNA editing in distantly related clades. This article is categorized under: RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution RNA Processing > RNA Editing and Modification.
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Affiliation(s)
- Yuange Duan
- State Key Laboratory of Protein and Plant Gene Research, Center for Bioinformatics, School of Life Sciences, Peking University, Beijing, China
| | - Xiaolu Tang
- State Key Laboratory of Protein and Plant Gene Research, Center for Bioinformatics, School of Life Sciences, Peking University, Beijing, China
| | - Jian Lu
- State Key Laboratory of Protein and Plant Gene Research, Center for Bioinformatics, School of Life Sciences, Peking University, Beijing, China
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34
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Xu C, Zhang J. Mammalian Alternative Translation Initiation Is Mostly Nonadaptive. Mol Biol Evol 2021; 37:2015-2028. [PMID: 32145028 DOI: 10.1093/molbev/msaa063] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Alternative translation initiation (ATLI) refers to the existence of multiple translation initiation sites per gene and is a widespread phenomenon in eukaryotes. ATLI is commonly assumed to be advantageous through creating proteome diversity or regulating protein synthesis. We here propose an alternative hypothesis that ATLI arises primarily from nonadaptive initiation errors presumably due to the limited ability of ribosomes to distinguish sequence motifs truly signaling translation initiation from similar sequences. Our hypothesis, but not the adaptive hypothesis, predicts a series of global patterns of ATLI, all of which are confirmed at the genomic scale by quantitative translation initiation sequencing in multiple human and mouse cell lines and tissues. Similarly, although many codons differing from AUG by one nucleotide can serve as start codons, our analysis suggests that using non-AUG start codons is mostly disadvantageous. These and other findings strongly suggest that ATLI predominantly results from molecular error, requiring a major revision of our understanding of the precision and regulation of translation initiation.
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Affiliation(s)
- Chuan Xu
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI
| | - Jianzhi Zhang
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI
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35
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Abstract
RNA editing is an RNA modification that alters the RNA sequence relative to its genomic blueprint. The most common type of RNA editing is A-to-I editing by double-stranded RNA-specific adenosine deaminase (ADAR) enzymes. Editing of a protein-coding region within the RNA molecule may result in non-synonymous substitutions, leading to a modified protein product. These editing sites, also known as "recoding" sites, contribute to the complexity and diversification of the proteome. Recent computational transcriptomic studies have identified thousands of recoding sites in multiple species, many of which are conserved within (but not usually across) lineages and have functional and evolutionary importance. In this chapter we describe the recoding phenomenon across species, consider its potential utility for diversity and adaptation, and discuss its evolution.
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36
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Specificity of RNA Folding and Its Association with Evolutionarily Adaptive mRNA Secondary Structures. GENOMICS PROTEOMICS & BIOINFORMATICS 2021; 19:882-900. [PMID: 33607297 PMCID: PMC9403030 DOI: 10.1016/j.gpb.2019.11.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 08/03/2019] [Accepted: 11/08/2019] [Indexed: 11/23/2022]
Abstract
The secondary structure is a fundamental feature of both noncoding and messenger RNAs. However, our understanding of the secondary structure of mRNA, especially that of the coding regions, remains elusive, likely due to translation and the lack of RNA-binding proteins that sustain the consensus structure, such as those that bind to noncoding RNA. Indeed, mRNA has recently been found to adopt diverse alternative structures, the overall functional significance of which remains untested. We hereby approached this problem by estimating the folding specificity, i.e., the probability that a fragment of RNA folds back to the same partner once refolded. We showed that the folding specificity of mRNA is lower than that of noncoding RNA and exhibits moderate evolutionary conservation. Notably, we found that specific rather than alternative folding is likely evolutionarily adaptive since specific folding is frequently associated with functionally important genes or sites within a gene. Additional analysis in combination with ribosome density suggests the ability to modulate ribosome movement as one potential functional advantage provided by specific folding. Our findings revealed a novel facet of the RNA structurome with important functional and evolutionary implications and indicated a potential method for distinguishing the mRNA secondary structures maintained by natural selection from molecular noise.
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37
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Duan Y, Dou S, Porath HT, Huang J, Eisenberg E, Lu J. A-to-I RNA editing in honeybees shows signals of adaptation and convergent evolution. iScience 2021; 24:101983. [PMID: 33458624 PMCID: PMC7797907 DOI: 10.1016/j.isci.2020.101983] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/18/2020] [Accepted: 12/17/2020] [Indexed: 12/27/2022] Open
Abstract
Social insects exhibit extensive phenotypic diversities among the genetically similar individuals, suggesting a role for the epigenetic regulations beyond the genome level. The ADAR-mediated adenosine-to-inosine (A-to-I) RNA editing, an evolutionarily conserved mechanism, facilitates adaptive evolution by expanding proteomic diversities. Here, we characterize the A-to-I RNA editome of honeybees (Apis mellifera), identifying 407 high-confidence A-to-I editing sites. Editing is most abundant in the heads and shows signatures for positive selection. Editing behavior differs between foragers and nurses, suggesting a role for editing in caste differentiation. Although only five sites are conserved between bees and flies, an unexpectedly large number of genes exhibit editing in both species, albeit at different locations, including the nonsynonymous auto-editing of Adar. This convergent evolution, where the same target genes independently acquire recoding events in distant diverged clades, together with the signals of adaptation observed in honeybees alone, further supports the notion of recoding being adaptive. Nonsynonymous editing sites in honeybees were under positive selection Differential editing may contribute to the phenotypic diversity between sub-castes Target genes acquire editing in different clades, suggesting convergent evolution
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Affiliation(s)
- Yuange Duan
- State Key Laboratory of Protein and Plant Gene Research, Center for Bioinformatics, School of Life Sciences, Peking University, Beijing, 100871, China.,Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Shengqian Dou
- State Key Laboratory of Protein and Plant Gene Research, Center for Bioinformatics, School of Life Sciences, Peking University, Beijing, 100871, China
| | - Hagit T Porath
- The Mina and Everard Goodman Faculty of Life Sciences, Bar Ilan University, Ramat-Gan 52900, Israel
| | - Jiaxing Huang
- Key Laboratory for Insect-Pollinator Biology of the Ministry of Agriculture and Rural Affairs, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, 100093, China
| | - Eli Eisenberg
- Raymond and Beverly Sackler School of Physics and Astronomy and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Jian Lu
- State Key Laboratory of Protein and Plant Gene Research, Center for Bioinformatics, School of Life Sciences, Peking University, Beijing, 100871, China
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Zhang H, Fu Q, Shi X, Pan Z, Yang W, Huang Z, Tang T, He X, Zhang R. Human A-to-I RNA editing SNP loci are enriched in GWAS signals for autoimmune diseases and under balancing selection. Genome Biol 2020; 21:288. [PMID: 33256812 PMCID: PMC7702712 DOI: 10.1186/s13059-020-02205-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 11/16/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Adenosine-to-inosine (A-to-I) RNA editing plays important roles in diversifying the transcriptome and preventing MDA5 sensing of endogenous dsRNA as nonself. To date, few studies have investigated the population genomic signatures of A-to-I editing due to the lack of editing sites overlapping with SNPs. RESULTS In this study, we applied a pipeline to robustly identify SNP editing sites from population transcriptomic data and combined functional genomics, GWAS, and population genomics approaches to study the function and evolution of A-to-I editing. We find that the G allele, which is equivalent to edited I, is overrepresented in editing SNPs. Functionally, A/G editing SNPs are highly enriched in GWAS signals of autoimmune and immune-related diseases. Evolutionarily, derived allele frequency distributions of A/G editing SNPs for both A and G alleles as the ancestral alleles are skewed toward intermediate frequency alleles relative to neutral SNPs, a hallmark of balancing selection, suggesting that both A and G alleles are functionally important. The signal of balancing selection is confirmed by a number of additional population genomic analyses. CONCLUSIONS We uncovered a hidden layer of A-to-I RNA editing SNP loci as a common target of balancing selection, and we propose that the maintenance of such editing SNP variations may be at least partially due to constraints on the resolution of the balance between immune activity and self-tolerance.
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Affiliation(s)
- Hui Zhang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, People's Republic of China
| | - Qiang Fu
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Xinrui Shi
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Ziqing Pan
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Wenbing Yang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Zichao Huang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Tian Tang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Xionglei He
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Rui Zhang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, People's Republic of China.
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, People's Republic of China.
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39
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Moldovan M, Chervontseva Z, Bazykin G, Gelfand MS. Adaptive evolution at mRNA editing sites in soft-bodied cephalopods. PeerJ 2020; 8:e10456. [PMID: 33312772 PMCID: PMC7703385 DOI: 10.7717/peerj.10456] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 11/09/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The bulk of variability in mRNA sequence arises due to mutation-change in DNA sequence which is heritable if it occurs in the germline. However, variation in mRNA can also be achieved by post-transcriptional modification including mRNA editing, changes in mRNA nucleotide sequence that mimic the effect of mutations. Such modifications are not inherited directly; however, as the processes affecting them are encoded in the genome, they have a heritable component, and therefore can be shaped by selection. In soft-bodied cephalopods, adenine-to-inosine RNA editing is very frequent, and much of it occurs at nonsynonymous sites, affecting the sequence of the encoded protein. METHODS We study selection regimes at coleoid A-to-I editing sites, estimate the prevalence of positive selection, and analyze interdependencies between the editing level and contextual characteristics of editing site. RESULTS Here, we show that mRNA editing of individual nonsynonymous sites in cephalopods originates in evolution through substitutions at regions adjacent to these sites. As such substitutions mimic the effect of the substitution at the edited site itself, we hypothesize that they are favored by selection if the inosine is selectively advantageous to adenine at the edited position. Consistent with this hypothesis, we show that edited adenines are more frequently substituted with guanine, an informational analog of inosine, in the course of evolution than their unedited counterparts, and for heavily edited adenines, these transitions are favored by positive selection. Our study shows that coleoid editing sites may enhance adaptation, which, together with recent observations on Drosophila and human editing sites, points at a general role of RNA editing in the molecular evolution of metazoans.
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Affiliation(s)
- Mikhail Moldovan
- Skolkovo Institute of Science and Technology, Moscow, Russian Federation
| | - Zoe Chervontseva
- Skolkovo Institute of Science and Technology, Moscow, Russian Federation
- A.A.Kharkevich Institute for Information Transmission Problems (RAS), Moscow, Russian Federation
| | - Georgii Bazykin
- Skolkovo Institute of Science and Technology, Moscow, Russian Federation
- A.A.Kharkevich Institute for Information Transmission Problems (RAS), Moscow, Russian Federation
| | - Mikhail S. Gelfand
- Skolkovo Institute of Science and Technology, Moscow, Russian Federation
- A.A.Kharkevich Institute for Information Transmission Problems (RAS), Moscow, Russian Federation
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40
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Ramos MJN, Coito JL, Faísca-Silva D, Cunha J, Costa MMR, Amâncio S, Rocheta M. Portuguese wild grapevine genome re-sequencing (Vitis vinifera sylvestris). Sci Rep 2020; 10:18993. [PMID: 33149248 PMCID: PMC7642406 DOI: 10.1038/s41598-020-76012-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 10/06/2020] [Indexed: 12/30/2022] Open
Abstract
The first genome of Vitis vinifera vinifera (PN40024), published in 2007, boosted grapevine related studies. While this reference genome is a suitable tool for the overall studies in the field, it lacks the ability to unveil changes accumulated during V. v. vinifera domestication. The subspecies V. v. sylvestris preserves wild characteristics, making it a good material to provide insights into V. v. vinifera domestication. The difference in the reproductive strategy between both subspecies is one of the characteristics that set them apart. While V. v. vinifera flowers are hermaphrodite, V. v. sylvestris is mostly dioecious. In this paper, we compare the re-sequencing of the genomes from a male and a female individual of the wild sylvestris, against the reference vinifera genome (PN40024). Variant analysis reveals a low number but with high impact modifications in coding regions, essentially non-synonymous single nucleotide polymorphisms and frame shifts caused by insertions and deletions. The sex-locus was manually inspected, and the results obtained are in line with the most recent works related with wild grapevine sex. In this paper we also describe for the first time RNA editing in transcripts of 14 genes in the sex-determining region, including VviYABBY and VviPLATZ.
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Affiliation(s)
- Miguel J N Ramos
- LEAF (Linking Landscape, Environment, Agriculture and Food) Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
| | - João L Coito
- LEAF (Linking Landscape, Environment, Agriculture and Food) Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal
| | - David Faísca-Silva
- LEAF (Linking Landscape, Environment, Agriculture and Food) Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal
| | - Jorge Cunha
- Instituto Nacional de Investigação Agrária E Veterinária, Quinta d'Almoinha, 2565-191, Dois Portos, Portugal
| | - M Manuela R Costa
- Plant Functional Biology Centre, Biosystems and Integrative Sciences Institute, University of Minho, 4710-057, Braga, Portugal
| | - Sara Amâncio
- LEAF (Linking Landscape, Environment, Agriculture and Food) Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal
| | - Margarida Rocheta
- LEAF (Linking Landscape, Environment, Agriculture and Food) Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
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41
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Teoh PJ, Koh MY, Chng WJ. ADARs, RNA editing and more in hematological malignancies. Leukemia 2020; 35:346-359. [PMID: 33139858 DOI: 10.1038/s41375-020-01076-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 08/21/2020] [Accepted: 10/20/2020] [Indexed: 02/08/2023]
Abstract
Adenosine-to-inosine (A-to-I) editing is the most prevalent type of RNA editing in humans, mediated by the adenosine deaminases acting on RNA (ADARs). Physiologically, these enzymes are present in the nucleus and/or the cytoplasm, where they catalyze the conversion of adenosines (A) to inosines (I) on double-stranded mRNA molecules. Aberrant ADAR-mediated-editing is a prominent feature in a variety of cancers. Importantly, the biological functions of ADARs and its functional implications in hematological malignancies have recently been unraveled. In this review, we will highlight the functions of ADARs and their involvements in cancer, specifically in hematological malignancies. RNA editing-independent function of cellular processes by ADARs and the potential of developing novel therapeutic approaches revolving RNA editing will also be discussed.
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Affiliation(s)
- Phaik Ju Teoh
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Cancer Science Institute of Singapore, Singapore, Singapore
| | - Mun Yee Koh
- Cancer Science Institute of Singapore, Singapore, Singapore
| | - Wee Joo Chng
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore. .,Cancer Science Institute of Singapore, Singapore, Singapore. .,Department of Haematology-Oncology, National University Cancer Institute of Singapore, National University Health System, Singapore, Singapore.
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42
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Brachova P, Alvarez NS, Hong X, Gunewardena S, Vincent KA, Latham KE, Christenson LK. Inosine RNA modifications are enriched at the codon wobble position in mouse oocytes and eggs†. Biol Reprod 2020; 101:938-949. [PMID: 31346607 DOI: 10.1093/biolre/ioz130] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/07/2019] [Accepted: 07/12/2019] [Indexed: 12/30/2022] Open
Abstract
Mammalian oocytes and eggs are transcriptionally quiescent and depend on post-transcriptional mechanisms for proper maturation. Post-transcriptional mRNA modifications comprise an important regulatory mechanism that can alter protein and miRNA recognition sites, splicing, stability, secondary structure, and protein coding. We discovered that fully grown mouse germinal vesicle oocytes and metaphase II eggs display abundant inosine mRNA modifications compared to growing oocytes from postnatal day 12 oocytes. These inosines were enriched in mRNA protein coding regions (CDS) and specifically located at the third codon base, or wobble position. Inosines, observed at lower frequencies in CDS of somatic tissues, were similarly enriched at the codon wobble position. In oocytes and eggs, inosine modifications lead primarily to synonymous changes in mRNA transcripts. Inosines may ultimately affect maternal mRNA stability by changing codon usage, thereby altering translational efficiency and translationally coupled mRNA degradation. These important observations advance our understanding of post-transcriptional mechanisms contributing to mammalian oocyte maturation.
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Affiliation(s)
- Pavla Brachova
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Nehemiah S Alvarez
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA.,De Novo Genomics, Kansas City, KS, USA
| | - Xiaoman Hong
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Sumedha Gunewardena
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Kailey A Vincent
- Department of Animal Science and Reproductive and Developmental Sciences Program, Michigan State University, East Lansing, MI, USA
| | - Keith E Latham
- Department of Animal Science and Reproductive and Developmental Sciences Program, Michigan State University, East Lansing, MI, USA
| | - Lane K Christenson
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA
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43
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Zhang H, Shi X, Huang T, Zhao X, Chen W, Gu N, Zhang R. Dynamic landscape and evolution of m6A methylation in human. Nucleic Acids Res 2020; 48:6251-6264. [PMID: 32406913 PMCID: PMC7293016 DOI: 10.1093/nar/gkaa347] [Citation(s) in RCA: 162] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/23/2020] [Accepted: 04/24/2020] [Indexed: 01/03/2023] Open
Abstract
m6A is a prevalent internal modification in mRNAs and has been linked to the diverse effects on mRNA fate. To explore the landscape and evolution of human m6A, we generated 27 m6A methylomes across major adult tissues. These data reveal dynamic m6A methylation across tissue types, uncover both broadly or tissue-specifically methylated sites, and identify an unexpected enrichment of m6A methylation at non-canonical cleavage sites. A comparison of fetal and adult m6A methylomes reveals that m6A preferentially occupies CDS regions in fetal tissues. Moreover, the m6A sub-motifs vary between fetal and adult tissues or across tissue types. From the evolutionary perspective, we uncover that the selection pressure on m6A sites varies and depends on their genic locations. Unexpectedly, we found that ∼40% of the 3′UTR m6A sites are under negative selection, which is higher than the evolutionary constraint on miRNA binding sites, and much higher than that on A-to-I RNA modification. Moreover, the recently gained m6A sites in human populations are clearly under positive selection and associated with traits or diseases. Our work provides a resource of human m6A profile for future studies of m6A functions, and suggests a role of m6A modification in human evolutionary adaptation and disease susceptibility.
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Affiliation(s)
- Hui Zhang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Xinrui Shi
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Tao Huang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Xueni Zhao
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Wanying Chen
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Nannan Gu
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Rui Zhang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China.,RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, PR China
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44
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Cai W, Shi L, Cao M, Shen D, Li J, Zhang S, Song J. Pan-RNA editing analysis of the bovine genome. RNA Biol 2020; 18:368-381. [PMID: 32794424 DOI: 10.1080/15476286.2020.1807724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
RNA editing is an essential process for modifying nucleotides at specific RNA sites during post-transcription in many species. However, its genomic landscape and characters have not been systematically explored in the bovine genome. In the present study, we characterized global RNA editing profiles from 50 samples of cattle and revealed a range of RNA editing profiles in different tissues. Most editing sites were significantly enriched in specific BovB-derived SINEs, especially the dispersed Bov-tAs, which likely forms dsRNA structures similar to the primate-specific Alu elements. Interestingly, ADARB1 (ADAR2) was observed to be predominant in determining global editing in the bovine genome. Common RNA editing sites among similar tissues were associated with tissue-specific biological functions. Taken together, the wide distribution of RNA editing sites and their tissue-specific characters implied the bovine RNA editome should be further explored.
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Affiliation(s)
- Wentao Cai
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.,Department of Animal and Avian Science, University of Maryland, College Park, USA.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture & National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Lijun Shi
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Mingyue Cao
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture & National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Dan Shen
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture & National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Junya Li
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Shengli Zhang
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture & National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Jiuzhou Song
- Department of Animal and Avian Science, University of Maryland, College Park, USA
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45
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Huang J, Zhang Y, Ma Q, Zhang Y, Wang M, Zhou Y, Xing Z, Jin M, Hu L, Kong X. Natural Selection on Exonic SNPs Shapes Allelic Expression Imbalance (AEI) Adaptability in Lung Cancer Progression. Front Genet 2020; 11:665. [PMID: 32670357 PMCID: PMC7327089 DOI: 10.3389/fgene.2020.00665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 06/01/2020] [Indexed: 01/28/2023] Open
Abstract
Tumors are driven by a sequence of genetic and epigenetic alterations. Previous studies have mostly focused on the roles of somatic mutations in tumorigenesis, but how germline variants act is largely unknown. In this study, we hypothesized that allelic expression imbalance (AEI) participated in the process of germline variants on tumorigenesis. We screened single-nucleotide polymorphisms (SNPs) as representative germline variants. By using 127 patients’ RNA sequencing data from paired lung cancer and adjacent normal tissues from public databases, we analyzed the effects of the functional consequence of SNPs, function and conservativeness on genes with AEI. We found that natural selection can affect AEI. Functional adaptability of genes with a high frequency of AEI and a correlation of the incidence of AEI with conservativeness were observed in both adjacent tissues and tumor tissues. Moreover, we observed a higher incidence of AEI in genes with non-synonymous SNPs than in those with synonymous SNPs. However, we also found that AEI was affected by allele expression noise, especially in tumor tissues, which led to an increased proportion of AEI, weakened the effect of natural selection and eliminated the influence of the functional consequence of SNPs on AEI. We unveiled a previously unknown adaptive regulatory mechanism in which the effect of natural selection on SNPs can be reflected in allelic expression, which provides insight into a better understanding of cancer evolution.
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Affiliation(s)
- Jinfei Huang
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yuchao Zhang
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Qingyang Ma
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yuhang Zhang
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Meng Wang
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - You Zhou
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zhihao Xing
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Meiling Jin
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Landian Hu
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Xiangyin Kong
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
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46
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Li T, Li Q, Li H, Xiao X, Ahmad Warraich D, Zhang N, Chen Z, Hou J, Liu T, Weng X, Liu Z, Hua J, Liao M. Pig-specific RNA editing during early embryo development revealed by genome-wide comparisons. FEBS Open Bio 2020; 10:1389-1402. [PMID: 32433824 PMCID: PMC7327910 DOI: 10.1002/2211-5463.12900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 05/15/2020] [Indexed: 12/19/2022] Open
Abstract
Posttranscriptional modification of mRNA sequences through RNA editing can increase transcriptome and proteome diversity in eukaryotes. Studies of fetal and adult tissues showed that adenosine‐to‐inosine RNA editing plays a crucial role in early human development, but there is a lack of global understanding of dynamic RNA editing during mammalian early embryonic development. Therefore, here we used RNA sequencing data from human, pig and mouse during early embryonic development to detect edited genes that may regulate stem cell pluripotency. We observed that although most of the RNA editing sites are located in intergenic, intron and UTR, a few editing sites are in coding regions and may result in nonsynonymous amino acid changes. Some editing sites are predicted to change the structure of a protein. We also report that HNF1A, TBX3, ACLY, ECI1 and ERDR1 are related to embryonic development and cell division.
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Affiliation(s)
- Tongtong Li
- College of Life Sciences, Northwest A&F University, Yangling, China
| | - Qun Li
- College of Life Sciences, Northwest A&F University, Yangling, China
| | - Hao Li
- College of Life Sciences, Northwest A&F University, Yangling, China
| | - Xia Xiao
- College of Life Sciences, Northwest A&F University, Yangling, China
| | | | - Ning Zhang
- College of Life Sciences, Northwest A&F University, Yangling, China
| | - Ziyun Chen
- College of Life Sciences, Northwest A&F University, Yangling, China
| | - Junyao Hou
- College of Life Sciences, Northwest A&F University, Yangling, China
| | - Tong Liu
- Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai Center for Plant Stress Biology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Xiaogang Weng
- Key Laboratory of Animal Cellular and Genetic Engineering of Heilongjiang Province, College of Life Science, Northeast Agricultural University, Harbin, China
| | - Zhonghua Liu
- Key Laboratory of Animal Cellular and Genetic Engineering of Heilongjiang Province, College of Life Science, Northeast Agricultural University, Harbin, China
| | - Jinlian Hua
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, China
| | - Mingzhi Liao
- College of Life Sciences, Northwest A&F University, Yangling, China
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47
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Shtratnikova VY, Schelkunov MI, Penin AA, Logacheva MD. Mitochondrial genome of the nonphotosynthetic mycoheterotrophic plant Hypopitys monotropa, its structure, gene expression and RNA editing. PeerJ 2020; 8:e9309. [PMID: 32601550 PMCID: PMC7307570 DOI: 10.7717/peerj.9309] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 05/17/2020] [Indexed: 01/05/2023] Open
Abstract
Heterotrophic plants—plants that have lost the ability to photosynthesize—are characterized by a number of changes at all levels of organization. Heterotrophic plants are divided into two large categories—parasitic and mycoheterotrophic (MHT). The question of to what extent such changes are similar in these two categories is still open. The plastid genomes of nonphotosynthetic plants are well characterized, and they exhibit similar patterns of reduction in the two groups. In contrast, little is known about the mitochondrial genomes of MHT plants. We report the structure of the mitochondrial genome of Hypopitys monotropa, a MHT member of Ericaceae, and the expression of its genes. In contrast to its highly reduced plastid genome, the mitochondrial genome of H. monotropa is larger than that of its photosynthetic relative Vaccinium macrocarpon, and its complete size is ~810 Kb. We observed an unusually long repeat-rich structure of the genome that suggests the existence of linear fragments. Despite this unique feature, the gene content of the H. monotropa mitogenome is typical of flowering plants. No acceleration of substitution rates is observed in mitochondrial genes, in contrast to previous observations in parasitic non-photosynthetic plants. Transcriptome sequencing revealed the trans-splicing of several genes and RNA editing in 33 of 38 genes. Notably, we did not find any traces of horizontal gene transfer from fungi, in contrast to plant parasites, which extensively integrate genetic material from their hosts.
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Affiliation(s)
- Viktoria Yu Shtratnikova
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Mikhail I Schelkunov
- Skolkovo Institute of Science and Technology, Moscow, Russia.,Laboratory of Plant Genomics, Institute for Information Transmission Problems of the Russian Academy of Sciences, Moscow, Russia
| | - Aleksey A Penin
- Laboratory of Plant Genomics, Institute for Information Transmission Problems of the Russian Academy of Sciences, Moscow, Russia
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48
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Popitsch N, Huber CD, Buchumenski I, Eisenberg E, Jantsch M, von Haeseler A, Gallach M. A-to-I RNA Editing Uncovers Hidden Signals of Adaptive Genome Evolution in Animals. Genome Biol Evol 2020; 12:345-357. [PMID: 32145015 PMCID: PMC7186786 DOI: 10.1093/gbe/evaa046] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2020] [Indexed: 02/06/2023] Open
Abstract
In animals, the most common type of RNA editing is the deamination of adenosines (A) into inosines (I). Because inosines basepair with cytosines (C), they are interpreted as guanosines (G) by the cellular machinery and genomically encoded G alleles at edited sites mimic the function of edited RNAs. The contribution of this hardwiring effect on genome evolution remains obscure. We looked for population genomics signatures of adaptive evolution associated with A-to-I RNA edited sites in humans and Drosophila melanogaster. We found that single nucleotide polymorphisms at edited sites occur 3 (humans) to 15 times (Drosophila) more often than at unedited sites, the nucleotide G is virtually the unique alternative allele at edited sites and G alleles segregate at higher frequency at edited sites than at unedited sites. Our study reveals that a significant fraction of coding synonymous and nonsynonymous as well as silent and intergenic A-to-I RNA editing sites are likely adaptive in the distantly related human and Drosophila lineages.
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Affiliation(s)
- Niko Popitsch
- Oxford NIHR Biomedical Research Center, Wellcome Trust Center for Human Genetics, University of Oxford, Oxford, United Kingdom
- Institute of Molecular Biotechnology (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Christian D Huber
- Australian Centre for Ancient DNA, The University of Adelaide, Adelaide, South Australia, Australia
| | - Ilana Buchumenski
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Eli Eisenberg
- Raymond and Beverly Sackler School of Physics and Astronomy and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Michael Jantsch
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
- Department for Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna, Austria
| | - Arndt von Haeseler
- Bioinformatics and Computational Biology, Faculty of Computer Science, University of Vienna, Vienna, Austria
- Center for Integrative Bioinformatics Vienna, Max F. Perutz Laboratories, University of Vienna and Medical University of Vienna, Vienna, Austria
| | - Miguel Gallach
- Center for Integrative Bioinformatics Vienna, Max F. Perutz Laboratories, University of Vienna and Medical University of Vienna, Vienna, Austria
- iLabSystems, C/Alicante, Castellón, Spain
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49
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Jiang D, Zhang J. The preponderance of nonsynonymous A-to-I RNA editing in coleoids is nonadaptive. Nat Commun 2019; 10:5411. [PMID: 31776345 PMCID: PMC6881472 DOI: 10.1038/s41467-019-13275-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 10/31/2019] [Indexed: 01/24/2023] Open
Abstract
A-to-I editing enzymatically converts the base adenosine (A) in RNA molecules to inosine (I), which is recognized as guanine (G) in translation. Exceptionally abundant A-to-I editing was recently discovered in the neural tissues of coleoids (octopuses, squids, and cuttlefishes), with a greater fraction of nonsynonymous sites than synonymous sites subject to high levels of editing. Although this phenomenon is thought to indicate widespread adaptive editing, its potential advantage is unknown. Here we propose an alternative, nonadaptive explanation. Specifically, increasing the cellular editing activity permits some otherwise harmful G-to-A nonsynonymous substitutions, because the As are edited to Is at sufficiently high levels. These high editing levels are constrained upon substitutions, resulting in the predominance of nonsynonymous editing at highly edited sites. Our evidence for this explanation suggests that the prevalent nonsynonymous editing in coleoids is generally nonadaptive, as in species with much lower editing activities. The neural tissues of coleoids have a greater fraction of nonsynonymous sites than synonymous sites subject to high levels of A-to-I RNA editing, a pattern thought to indicate widespread adaptive editing. Here the authors propose and provide evidence for an alternative, nonadaptive explanation.
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Affiliation(s)
- Daohan Jiang
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jianzhi Zhang
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA.
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50
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Mai TL, Chuang TJ. A-to-I RNA editing contributes to the persistence of predicted damaging mutations in populations. Genome Res 2019; 29:1766-1776. [PMID: 31515285 PMCID: PMC6836733 DOI: 10.1101/gr.246033.118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 09/04/2019] [Indexed: 12/13/2022]
Abstract
Adenosine-to-inosine (A-to-I) RNA editing is a very common co-/posttranscriptional modification that can lead to A-to-G changes at the RNA level and compensate for G-to-A genomic changes to a certain extent. It has been shown that each healthy individual can carry dozens of missense variants predicted to be severely deleterious. Why strongly detrimental variants are preserved in a population and not eliminated by negative natural selection remains mostly unclear. Here, we ask if RNA editing correlates with the burden of deleterious A/G polymorphisms in a population. Integrating genome and transcriptome sequencing data from 447 human lymphoblastoid cell lines, we show that nonsynonymous editing activities (prevalence/level) are negatively correlated with the deleteriousness of A-to-G genomic changes and positively correlated with that of G-to-A genomic changes within the population. We find a significantly negative correlation between nonsynonymous editing activities and allele frequency of A within the population. This negative editing-allele frequency correlation is particularly strong when editing sites are located in highly important genes/loci. Examinations of deleterious missense variants from the 1000 Genomes Project further show a significantly higher proportion of rare missense mutations for G-to-A changes than for other types of changes. The proportion for G-to-A changes increases with increasing deleterious effects of the changes. Moreover, the deleteriousness of G-to-A changes is significantly positively correlated with the percentage of editing enzyme binding motifs at the variants. Overall, we show that nonsynonymous editing is associated with the increased burden of G-to-A missense mutations in healthy individuals, expanding RNA editing in pathogenomics studies.
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Affiliation(s)
- Te-Lun Mai
- Genomics Research Center, Academia Sinica, Taipei 11529, Taiwan
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