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Jung H, Park HJ, Jo SH, Lee A, Lee HJ, Kim HS, Jung C, Cho HS. Nuclear OsFKBP20-1b maintains SR34 stability and promotes the splicing of retained introns upon ABA exposure in rice. THE NEW PHYTOLOGIST 2023; 238:2476-2494. [PMID: 36942934 DOI: 10.1111/nph.18892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 03/16/2023] [Indexed: 05/19/2023]
Abstract
Alternative splicing (AS) is a critical means by which plants respond to changes in the environment, but few splicing factors contributing to AS have been reported and functionally characterized in rice (Oryza sativa L.). Here, we explored the function and molecular mechanism of the spliceosome-associated protein OsFKBP20-1b during AS. We determined the AS landscape of wild-type and osfkbp20-1b knockout plants upon abscisic acid (ABA) treatment by transcriptome deep sequencing. To capture the dynamics of translating intron-containing mRNAs, we blocked transcription with cordycepin and performed polysome profiling. We also analyzed whether OsFKBP20-1b and the splicing factors OsSR34 and OsSR45 function together in AS using protoplast transfection assays. We show that OsFKBP20-1b interacts with OsSR34 and regulates its stability, suggesting a role as a chaperone-like protein in the spliceosome. OsFKBP20-1b facilitates the splicing of mRNAs with retained introns after ABA treatment; some of these mRNAs are translatable and encode functional transcriptional regulators of stress-responsive genes. In addition, interacting proteins, OsSR34 and OsSR45, regulate the splicing of the same retained introns as OsFKBP20-1b after ABA treatment. Our findings reveal that spliceosome-associated immunophilin functions in alternative RNA splicing in rice by positively regulating the splicing of retained introns to limit ABA response.
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Affiliation(s)
- Haemyeong Jung
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Hyun Ji Park
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
| | - Seung Hee Jo
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Areum Lee
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Hyo-Jun Lee
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Functional Genomics, KRIBB School of Bioscience, UST, Daejeon, 34113, South Korea
| | - Hyun-Soon Kim
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
| | - Choonkyun Jung
- Department of International Agricultural Technology and Crop Biotechnology Institute/Green Bio Science and Technology, Seoul National University, Pyeongchang, 25354, South Korea
- Department of Agriculture, Forestry, and Bioresources and Integrated Major in Global Smart Farm, College of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, South Korea
| | - Hye Sun Cho
- Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon, 34113, South Korea
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David JK, Maden SK, Wood MA, Thompson RF, Nellore A. Retained introns in long RNA-seq reads are not reliably detected in sample-matched short reads. Genome Biol 2022; 23:240. [PMID: 36369064 PMCID: PMC9652823 DOI: 10.1186/s13059-022-02789-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 10/10/2022] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND There is growing interest in retained introns in a variety of disease contexts including cancer and aging. Many software tools have been developed to detect retained introns from short RNA-seq reads, but reliable detection is complicated by overlapping genes and transcripts as well as the presence of unprocessed or partially processed RNAs. RESULTS We compared introns detected by 8 tools using short RNA-seq reads with introns observed in long RNA-seq reads from the same biological specimens. We found significant disagreement among tools (Fleiss' [Formula: see text]) such that 47.7% of all detected intron retentions were not called by more than one tool. We also observed poor performance of all tools, with none achieving an F1-score greater than 0.26, and qualitatively different behaviors between general-purpose alternative splicing detection tools and tools confined to retained intron detection. CONCLUSIONS Short-read tools detect intron retention with poor recall and precision, calling into question the completeness and validity of a large percentage of putatively retained introns called by commonly used methods.
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Affiliation(s)
- Julianne K. David
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR USA ,Present Address: Base5 Genomics, Inc., Mountain View, CA USA
| | - Sean K. Maden
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR USA ,grid.21107.350000 0001 2171 9311Present Address: Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD USA
| | - Mary A. Wood
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.429936.30000 0004 5914 210XPortland VA Research Foundation, Portland, OR USA ,Present Address: Phase Genomics, Inc., Seattle, WA USA
| | - Reid F. Thompson
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR USA ,grid.484322.bDivision of Hospital and Specialty Medicine, VA Portland Healthcare System, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Medical Informatics & Clinical Epidemiology, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Radiation Medicine, Oregon Health & Science University, Portland, OR USA
| | - Abhinav Nellore
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Surgery, Oregon Health & Science University, Portland, OR USA
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Bogias KJ, Pederson SM, Leemaqz S, Smith MD, McAninch D, Jankovic-Karasoulos T, McCullough D, Wan Q, Bianco-Miotto T, Breen J, Roberts CT. Placental Transcription Profiling in 6-23 Weeks' Gestation Reveals Differential Transcript Usage in Early Development. Int J Mol Sci 2022; 23:ijms23094506. [PMID: 35562897 PMCID: PMC9105363 DOI: 10.3390/ijms23094506] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 12/13/2022] Open
Abstract
The human placenta is a rapidly developing transient organ that is key to pregnancy success. Early development of the conceptus occurs in a low oxygen environment before oxygenated maternal blood begins to flow into the placenta at ~10-12 weeks' gestation. This process is likely to substantially affect overall placental gene expression. Transcript variability underlying gene expression has yet to be profiled. In this study, accurate transcript expression profiles were identified for 84 human placental chorionic villus tissue samples collected across 6-23 weeks' gestation. Differential gene expression (DGE), differential transcript expression (DTE) and differential transcript usage (DTU) between 6-10 weeks' and 11-23 weeks' gestation groups were assessed. In total, 229 genes had significant DTE yet no significant DGE. Integration of DGE and DTE analyses found that differential expression patterns of individual transcripts were commonly masked upon aggregation to the gene-level. Of the 611 genes that exhibited DTU, 534 had no significant DGE or DTE. The four most significant DTU genes ADAM10, VMP1, GPR126, and ASAH1, were associated with hypoxia-responsive pathways. Transcript usage is a likely regulatory mechanism in early placentation. Identification of functional roles will facilitate new insight in understanding the origins of pregnancy complications.
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Affiliation(s)
- Konstantinos J. Bogias
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
| | - Stephen M. Pederson
- Dame Roma Mitchell Cancer Research Laboratories, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia;
| | - Shalem Leemaqz
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Melanie D. Smith
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Dale McAninch
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
| | - Tanja Jankovic-Karasoulos
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Dylan McCullough
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Qianhui Wan
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Tina Bianco-Miotto
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
- School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, Adelaide, SA 5005, Australia
| | - James Breen
- Indigenous Genomics, Telethon Kids Institute (Adelaide Office), Adelaide, SA 5000, Australia;
- College of Health & Medicine, Australian National University, Canberra, ACT 2600, Australia
| | - Claire T. Roberts
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
- Correspondence:
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Wu W, Syed F, Simpson E, Lee CC, Liu J, Chang G, Dong C, Seitz C, Eizirik DL, Mirmira RG, Liu Y, Evans-Molina C. The Impact of Pro-Inflammatory Cytokines on Alternative Splicing Patterns in Human Islets. Diabetes 2021; 71:db200847. [PMID: 34697029 PMCID: PMC8763875 DOI: 10.2337/db20-0847] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 10/18/2021] [Indexed: 01/05/2023]
Abstract
Alternative splicing (AS) within the β cell has been proposed as one potential pathway that may exacerbate autoimmunity and unveil novel immunogenic epitopes in type 1 diabetes (T1D). We employed a computational strategy to prioritize pathogenic splicing events in human islets treated with IL-1β + IFN-γ as an ex vivo model of T1D and coupled this analysis with a k-mer based approach to predict RNA binding proteins involved in AS. In total, 969 AS events were identified in cytokine-treated islets, with the majority (44.8%) involving a skipped exon. ExonImpact identified 129 events predicted to impact protein structure. AS occurred with high frequency in MHC Class II-related mRNAs, and targeted qPCR validated reduced inclusion of Exon5 in the MHC Class II gene HLA-DMB. Single molecule RNA FISH confirmed increased HLA-DMB splicing in pancreatic sections from human donors with established T1D and autoantibody positivity. Serine and Arginine Rich Splicing Factor 2 was implicated in 37.2% of potentially pathogenic events, including Exon5 exclusion in HLA-DMB. Together, these data suggest that dynamic control of AS plays a role in the β cell response to inflammatory signals during T1D evolution.
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Affiliation(s)
- Wenting Wu
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, Indiana
| | - Farooq Syed
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, Indiana
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Edward Simpson
- Department of BioHealth Informatics, Indiana University School of Informatics and Computing, Indianapolis, IN, USA
| | - Chih-Chun Lee
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, Indiana
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Jing Liu
- Department of Physics, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Garrick Chang
- Department of Physics, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Chuanpeng Dong
- Department of BioHealth Informatics, Indiana University School of Informatics and Computing, Indianapolis, IN, USA
| | - Clayton Seitz
- Department of Physics, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Decio L Eizirik
- ULB Center for Diabetes Research, Medical Faculty, Universitê Libre de Bruxelles (ULB), Brussels, Belgium
- Indiana Biosciences Research Institute (IBRI), Indianapolis, Indiana, USA
| | - Raghavendra G Mirmira
- Kovler Diabetes Center and Department of Medicine, The University of Chicago, Chicago, IL, USA
| | - Yunlong Liu
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Carmella Evans-Molina
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, Indiana
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
- Richard L. Roudebush VA Medical Center, Indiana University School of Informatics and Computing, Indianapolis, IN, USA
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5
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The splicing factor XAB2 interacts with ERCC1-XPF and XPG for R-loop processing. Nat Commun 2021; 12:3153. [PMID: 34039990 PMCID: PMC8155215 DOI: 10.1038/s41467-021-23505-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 04/27/2021] [Indexed: 12/11/2022] Open
Abstract
RNA splicing, transcription and the DNA damage response are intriguingly linked in mammals but the underlying mechanisms remain poorly understood. Using an in vivo biotinylation tagging approach in mice, we show that the splicing factor XAB2 interacts with the core spliceosome and that it binds to spliceosomal U4 and U6 snRNAs and pre-mRNAs in developing livers. XAB2 depletion leads to aberrant intron retention, R-loop formation and DNA damage in cells. Studies in illudin S-treated cells and Csbm/m developing livers reveal that transcription-blocking DNA lesions trigger the release of XAB2 from all RNA targets tested. Immunoprecipitation studies reveal that XAB2 interacts with ERCC1-XPF and XPG endonucleases outside nucleotide excision repair and that the trimeric protein complex binds RNA:DNA hybrids under conditions that favor the formation of R-loops. Thus, XAB2 functionally links the spliceosomal response to DNA damage with R-loop processing with important ramifications for transcription-coupled DNA repair disorders. XPA-binding protein (XAB)-2 is the human homologue of the yeast pre-mRNA splicing factor Syf1. Here the authors use an in vivo biotinylation tagging approach to show XAB2’s role in DNA repair, RNA splicing and transcription during mammalian development.
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6
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Abstract
The number of complete genome sequences explodes more and more with each passing year. Thus, methods for genome annotation need to be honed constantly to handle the deluge of information. Annotation of pseudogenes (i.e., gene copies that appear not to make a functional protein) in genomes is a persistent problem; here, we overview pseudogene annotation methods that are based on the detection of sequence homology in genomic DNA.
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Affiliation(s)
- Paul M Harrison
- Department of Biology, McGill University, Montreal, QC, Canada.
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7
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Zheng JT, Lin CX, Fang ZY, Li HD. Intron Retention as a Mode for RNA-Seq Data Analysis. Front Genet 2020; 11:586. [PMID: 32733531 PMCID: PMC7358572 DOI: 10.3389/fgene.2020.00586] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 05/14/2020] [Indexed: 12/16/2022] Open
Abstract
Intron retention (IR) is an alternative splicing mode whereby introns, rather than being spliced out as usual, are retained in mature mRNAs. It was previously considered a consequence of mis-splicing and received very limited attention. Only recently has IR become of interest for transcriptomic data analysis owing to its recognized roles in gene expression regulation and associations with complex diseases. In this article, we first review the function of IR in regulating gene expression in a number of biological processes, such as neuron differentiation and activation of CD4+ T cells. Next, we briefly review its association with diseases, such as Alzheimer's disease and cancers. Then, we describe state-of-the-art methods for IR detection, including RNA-seq analysis tools IRFinder and iREAD, highlighting their underlying principles and discussing their advantages and limitations. Finally, we discuss the challenges for IR detection and potential ways in which IR detection methods could be improved.
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Affiliation(s)
- Jian-Tao Zheng
- Hunan Provincial Key Lab on Bioinformatics, Center for Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha, China
| | - Cui-Xiang Lin
- Hunan Provincial Key Lab on Bioinformatics, Center for Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha, China
| | - Zhao-Yu Fang
- School of Mathematics and Statistics, Central South University, Changsha, China
| | - Hong-Dong Li
- Hunan Provincial Key Lab on Bioinformatics, Center for Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha, China
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Kishor A, Fritz SE, Hogg JR. Nonsense-mediated mRNA decay: The challenge of telling right from wrong in a complex transcriptome. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 10:e1548. [PMID: 31131562 DOI: 10.1002/wrna.1548] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/01/2019] [Accepted: 05/07/2019] [Indexed: 12/18/2022]
Abstract
The nonsense-mediated mRNA decay pathway selects and degrades its targets using a dense network of RNA-protein and protein-protein interactions. Together, these interactions allow the pathway to collect copious information about the translating mRNA, including translation termination status, splice junction positions, mRNP composition, and 3'UTR length and structure. The core NMD machinery, centered on the RNA helicase UPF1, integrates this information to determine the efficiency of decay. A picture of NMD is emerging in which many factors contribute to the dynamics of decay complex assembly and disassembly, thereby influencing the probability of decay. The ability of the NMD pathway to recognize mRNP features of diverse potential substrates allows it to simultaneously perform quality control and regulatory functions. In vertebrates, increased transcriptome complexity requires balance between these two functions since high NMD efficiency is desirable for maintenance of quality control fidelity but may impair expression of normal mRNAs. NMD has adapted to this challenge by employing mechanisms to enhance identification of certain potential substrates, while using sequence-specific RNA-binding proteins to shield others from detection. These elaborations on the conserved NMD mechanism permit more sensitive post-transcriptional gene regulation but can have severe deleterious consequences, including the failure to degrade pathogenic aberrant mRNAs in many B cell lymphomas. This article is categorized under: RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms.
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Affiliation(s)
- Aparna Kishor
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Sarah E Fritz
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - J Robert Hogg
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
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Sanyal RP, Misra HS, Saini A. Heat-stress priming and alternative splicing-linked memory. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:2431-2434. [PMID: 29718462 PMCID: PMC5920290 DOI: 10.1093/jxb/ery111] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
This article comments on: Ling Y, Serrano N, Gao G, Atia M, Mokhtar M, Woo YH, Bazin J, Veluchamy A, Benhamed M, Crespi M, Gehring C, Reddy ASN, Mahfouz MM. 2018. Thermopriming triggers splicing memory in Arabidopsis. Journal of Experimental Botany 69, 2659–2675.
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Affiliation(s)
- Ravi P Sanyal
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, Maharashtra, India
- Homi Bhabha National Institute, Anushaktinagar, Trombay, Mumbai, Maharashtra, India
| | - Hari S Misra
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, Maharashtra, India
- Homi Bhabha National Institute, Anushaktinagar, Trombay, Mumbai, Maharashtra, India
| | - Ajay Saini
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, Maharashtra, India
- Homi Bhabha National Institute, Anushaktinagar, Trombay, Mumbai, Maharashtra, India
- Correspondence:
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10
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Muir VS, Gasch AP, Anderson P. The Substrates of Nonsense-Mediated mRNA Decay in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2018; 8:195-205. [PMID: 29122854 PMCID: PMC5765348 DOI: 10.1534/g3.117.300254] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 11/07/2017] [Indexed: 12/27/2022]
Abstract
Nonsense-mediated mRNA decay (NMD) is a conserved pathway that strongly influences eukaryotic gene expression. Inactivating or inhibiting NMD affects the abundance of a substantial fraction of the transcriptome in numerous species. Transcripts whose abundance is altered in NMD-deficient cells may represent either direct substrates of NMD or indirect effects of inhibiting NMD. We present a genome-wide investigation of the direct substrates of NMD in Caenorhabditis elegans Our goals were (i) to identify mRNA substrates of NMD and (ii) to distinguish those mRNAs from others whose abundance is indirectly influenced by the absence of NMD. We previously demonstrated that Upf1p/SMG-2, the central effector of NMD in all studied eukaryotes, preferentially associates with mRNAs that contain premature translation termination codons. We used this preferential association to distinguish direct from indirect effects by coupling immunopurification of Upf1/SMG-2 with high-throughput mRNA sequencing of NMD-deficient mutants and NMD-proficient controls. We identify 680 substrates of NMD, 171 of which contain novel spliced forms that (i) include sequences of annotated introns and (ii) have not been previously documented in the C. elegans transcriptome. NMD degrades unproductively spliced mRNAs with sufficient efficiency in NMD-proficient strains that such mRNAs were not previously known. Two classes of genes are enriched among the identified NMD substrates: (i) mRNAs of expressed pseudogenes and (ii) mRNAs of gene families whose gene number has recently expanded in the C. elegans genome. Our results identify novel NMD substrates and provide a context for understanding NMD's role in normal gene expression and genome evolution.
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Affiliation(s)
- Virginia S Muir
- Laboratory of Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Audrey P Gasch
- Laboratory of Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Philip Anderson
- Laboratory of Genetics, University of Wisconsin-Madison, Wisconsin 53706
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11
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Human nonsense-mediated RNA decay regulates EMT by targeting the TGF-ß signaling pathway in lung adenocarcinoma. Cancer Lett 2017; 403:246-259. [PMID: 28663146 DOI: 10.1016/j.canlet.2017.06.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 05/04/2017] [Accepted: 06/16/2017] [Indexed: 11/20/2022]
Abstract
Nonsense-mediated mRNA decay (NMD) is a highly conserved pathway that selectively degrades aberrant RNA transcripts. In this study, we proved that NMD regulates the epithelial-mesenchymal transition (EMT) of lung adenocarcinoma (ADC). Moreover, we found that NMD core factor UP-frameshift 1 tends to be expressed at lower levels in human ADC tissues than in normal lung tissues, thereby raising the possibility that NMD may be downregulated to permit ADC oncogenesis. Our experiments in human ADC cell lines showed that downregulating NMD can promote EMT. Moreover, EMT can be inhibited by upregulating NMD. We tested the role of TGF-ß signaling and found that NMD influences EMT by targeting the TGF-ß signaling pathway. Our findings reveal that NMD is a potential tumor regulatory mechanism and may be a potential therapeutic target for ADC.
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12
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Harada N, Okuyama M, Yoshikatsu A, Yamamoto H, Ishiwata S, Hamada C, Hirose T, Shono M, Kuroda M, Tsutsumi R, Takeo J, Taketani Y, Nakaya Y, Sakaue H. Endoplasmic Reticulum Stress in Mice Increases Hepatic Expression of Genes Carrying a Premature Termination Codon via a Nutritional Status‐Independent GRP78‐Dependent Mechanism. J Cell Biochem 2017; 118:3810-3824. [DOI: 10.1002/jcb.26031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 04/04/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Nagakatsu Harada
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Maiko Okuyama
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Aya Yoshikatsu
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Hironori Yamamoto
- Faculty of Human LifeDepartment of Health and NutritionJin‐ai University3‐1‐1 Ohde‐choEchizen City915‐8586Japan
| | - Saori Ishiwata
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Chikako Hamada
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Tomoyo Hirose
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Masayuki Shono
- Support Center for Advanced Medical SciencesInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Masashi Kuroda
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Rie Tsutsumi
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Jiro Takeo
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
- Central Research LaboratoryNippon Suisan Kaisha32‐3 Nanakuni 1 ChomeHachiojiTokyo192‐0991Japan
| | - Yutaka Taketani
- Department of Clinical Nutrition and Food ManagementInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Yutaka Nakaya
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
| | - Hiroshi Sakaue
- Department of Nutrition and MetabolismInstitute of Biomedical SciencesTokushima University Graduate School3‐18‐15, Kuramoto‐choTokushima City770‐8503Japan
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13
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Genomic, Transcriptomic, and Proteomic Analysis Provide Insights Into the Cold Adaptation Mechanism of the Obligate Psychrophilic Fungus Mrakia psychrophila. G3-GENES GENOMES GENETICS 2016; 6:3603-3613. [PMID: 27633791 PMCID: PMC5100859 DOI: 10.1534/g3.116.033308] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Mrakia psychrophila is an obligate psychrophilic fungus. The cold adaptation mechanism of psychrophilic fungi remains unknown. Comparative genomics analysis indicated that M. psychrophila had a specific codon usage preference, especially for codons of Gly and Arg and its major facilitator superfamily (MFS) transporter gene family was expanded. Transcriptomic analysis revealed that genes involved in ribosome and energy metabolism were upregulated at 4°, while genes involved in unfolded protein binding, protein processing in the endoplasmic reticulum, proteasome, spliceosome, and mRNA surveillance were upregulated at 20°. In addition, genes related to unfolded protein binding were alternatively spliced. Consistent with other psychrophiles, desaturase and glycerol 3-phosphate dehydrogenase, which are involved in biosynthesis of unsaturated fatty acid and glycerol respectively, were upregulated at 4°. Cold adaptation of M. psychrophila is mediated by synthesizing unsaturated fatty acids to maintain membrane fluidity and accumulating glycerol as a cryoprotectant. The proteomic analysis indicated that the correlations between the dynamic patterns between transcript level changes and protein level changes for some pathways were positive at 4°, but negative at 20°. The death of M. psychrophila above 20° might be caused by an unfolded protein response.
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14
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Mammalian introns: when the junk generates molecular diversity. Int J Mol Sci 2015; 16:4429-52. [PMID: 25710723 PMCID: PMC4394429 DOI: 10.3390/ijms16034429] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/06/2015] [Accepted: 02/11/2015] [Indexed: 01/14/2023] Open
Abstract
Introns represent almost half of the human genome, yet their vast majority is eliminated from eukaryotic transcripts through RNA splicing. Nevertheless, they feature key elements and functions that deserve further interest. At the level of DNA, introns are genomic segments that can shelter independent transcription units for coding and non-coding RNAs which transcription may interfere with that of the host gene, and regulatory elements that can influence gene expression and splicing itself. From the RNA perspective, some introns can be subjected to alternative splicing. Intron retention appear to provide some plasticity to the nature of the protein produced, its distribution in a given cell type and timing of its translation. Intron retention may also serve as a switch to produce coding or non-coding RNAs from the same transcription unit. Conversely, splicing of introns has been directly implicated in the production of small regulatory RNAs. Hence, splicing of introns also appears to provide plasticity to the type of RNA produced from a genetic locus (coding, non-coding, short or long). We addressed these aspects to add to our understanding of mechanisms that control the fate of introns and could be instrumental in regulating genomic output and hence cell fate.
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15
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Provost-Javier KN, Rasgon JL. 20-hydroxyecdysone mediates non-canonical regulation of mosquito vitellogenins through alternative splicing. INSECT MOLECULAR BIOLOGY 2014; 23:407-416. [PMID: 24720618 PMCID: PMC4288586 DOI: 10.1111/imb.12092] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Vitellogenesis is one of the most well-studied physiological processes in mosquitoes. Expression of mosquito vitellogenin genes is classically described as being restricted to female adult reproduction. We report premature vitellogenin transcript expression in three vector mosquitoes: Culex tarsalis, Aedes aegypti and Anopheles gambiae. Vitellogenins expressed during non-reproductive stages are alternatively spliced to retain their first intron and encode premature termination codons. We show that intron retention results in transcript degradation by translation-dependent nonsense-mediated mRNA decay. This is probably an example of regulated unproductive splicing and translation (RUST), a mechanism known to regulate gene expression in numerous organisms but which has never been described in mosquitoes. We demonstrate that the hormone 20-hydroxyecdysone (20E) is responsible for regulating post-transcriptional splicing of vitellogenin. After exposure of previtellogenic fat bodies to 20E, vitellogenin expression switches from a non-productive intron-retaining transcript to a spliced protein-coding transcript. This effect is independent of factors classically known to influence transcription, such as juvenile hormone-mediated competence and amino acid signalling through the target of rapamycin pathway. Non-canonical regulation of vitellogenesis through RUST is a novel role for the multifunctional hormone 20E, and may have important implications for general patterns of gene regulation in mosquitoes.
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Affiliation(s)
- K N Provost-Javier
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe Street, Baltimore, MD, 21205, USA
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16
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Göhring J, Jacak J, Barta A. Imaging of endogenous messenger RNA splice variants in living cells reveals nuclear retention of transcripts inaccessible to nonsense-mediated decay in Arabidopsis. THE PLANT CELL 2014; 26:754-64. [PMID: 24532591 PMCID: PMC3967038 DOI: 10.1105/tpc.113.118075] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 01/14/2014] [Accepted: 01/26/2014] [Indexed: 05/18/2023]
Abstract
Alternative splicing (AS) is an important regulatory process that leads to the creation of multiple RNA transcripts from a single gene. Alternative transcripts often carry premature termination codons (PTCs), which trigger nonsense-mediated decay (NMD), a cytoplasmic RNA degradation pathway. However, intron retention, the most prevalent AS event in plants, often leads to PTC-carrying splice variants that are insensitive to NMD; this led us to question the fate of these special RNA variants. Here, we present an innovative approach to monitor and characterize endogenous mRNA splice variants within living plant cells. This method combines standard confocal laser scanning microscopy for molecular beacon detection with a robust statistical pipeline for sample comparison. We demonstrate this technique on the localization of NMD-insensitive splice variants of two Arabidopsis thaliana genes, RS2Z33 and the SEF factor. The experiments reveal that these intron-containing splice variants remain within the nucleus, which allows them to escape the NMD machinery. Moreover, fluorescence recovery after photobleaching experiments in the nucleoplasm show a decreased mobility of intron-retained mRNAs compared with fully spliced RNAs. In addition, differences in mobility were observed for an mRNA dependent on its origin from an intron-free or an intron-containing gene.
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17
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Abstract
The number of complete genome sequences explodes more and more with each passing year. Thus, methods for genome annotation need to be honed constantly to handle the deluge of information. Annotation of pseudogenes (i.e., gene copies that appear not to make a functional protein) in genomes is a persistent problem; here, we overview pseudogene annotation methods that are based on the detection of sequence homology in genomic DNA.
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Affiliation(s)
- Paul M Harrison
- Department of Biology, McGill University, Stewart Biology Building, 1205 Doctor Penfield Avenue, Montreal, QC, Canada, H3A 1B1,
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18
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Identification of a PTC-containing DlRan transcript and its differential expression during somatic embryogenesis in Dimocarpus longan. Gene 2013; 529:37-44. [DOI: 10.1016/j.gene.2013.07.091] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 05/19/2013] [Accepted: 07/25/2013] [Indexed: 11/17/2022]
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19
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Karam R, Wengrod J, Gardner LB, Wilkinson MF. Regulation of nonsense-mediated mRNA decay: implications for physiology and disease. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2013; 1829:624-33. [PMID: 23500037 DOI: 10.1016/j.bbagrm.2013.03.002] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 03/02/2013] [Accepted: 03/04/2013] [Indexed: 01/24/2023]
Abstract
Nonsense-mediated mRNA decay (NMD) is an mRNA quality control mechanism that destabilizes aberrant mRNAs harboring premature termination (nonsense) codons (PTCs). Recent studies have shown that NMD also targets mRNAs transcribed from a large subset of wild-type genes. This raises the possibility that NMD itself is under regulatory control. Indeed, several recent studies have shown that NMD activity is modulated in specific cell types and that key components of the NMD pathway are regulated by several pathways, including microRNA circuits and NMD itself. Cellular stress also modulates the magnitude of NMD by mechanisms that are beginning to be understood. Here, we review the evidence that NMD is regulated and discuss the physiological role for this regulation. We propose that the efficiency of NMD is altered in some cellular contexts to regulate normal biological events. In disease states-such as in cancer-NMD is disturbed by intrinsic and extrinsic factors, resulting in altered levels of crucial NMD-targeted mRNAs that lead to downstream pathological consequences. This article is part of a Special Issue entitled: RNA Decay mechanisms.
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Affiliation(s)
- Rachid Karam
- Department of Reproductive Medicine, University of California, San Diego, CA 92093-0864, USA
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20
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Yap K, Makeyev EV. Regulation of gene expression in mammalian nervous system through alternative pre-mRNA splicing coupled with RNA quality control mechanisms. Mol Cell Neurosci 2013; 56:420-8. [PMID: 23357783 DOI: 10.1016/j.mcn.2013.01.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 01/15/2013] [Accepted: 01/17/2013] [Indexed: 12/12/2022] Open
Abstract
Eukaryotic gene expression is orchestrated on a genome-wide scale through several post-transcriptional mechanisms. Of these, alternative pre-mRNA splicing expands the proteome diversity and modulates mRNA stability through downstream RNA quality control (QC) pathways including nonsense-mediated decay (NMD) of mRNAs containing premature termination codons and nuclear retention and elimination (NRE) of intron-containing transcripts. Although originally identified as mechanisms for eliminating aberrant transcripts, a growing body of evidence suggests that NMD and NRE coupled with deliberate changes in pre-mRNA splicing patterns are also used in a number of biological contexts for deterministic control of gene expression. Here we review recent studies elucidating molecular mechanisms and biological significance of these gene regulation strategies with a specific focus on their roles in nervous system development and physiology. This article is part of a Special Issue entitled 'RNA and splicing regulation in neurodegeneration'.
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Affiliation(s)
- Karen Yap
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
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21
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Shabalina SA, Spiridonov NA, Kashina A. Sounds of silence: synonymous nucleotides as a key to biological regulation and complexity. Nucleic Acids Res 2013; 41:2073-94. [PMID: 23293005 PMCID: PMC3575835 DOI: 10.1093/nar/gks1205] [Citation(s) in RCA: 187] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Messenger RNA is a key component of an intricate regulatory network of its own. It accommodates numerous nucleotide signals that overlap protein coding sequences and are responsible for multiple levels of regulation and generation of biological complexity. A wealth of structural and regulatory information, which mRNA carries in addition to the encoded amino acid sequence, raises the question of how these signals and overlapping codes are delineated along non-synonymous and synonymous positions in protein coding regions, especially in eukaryotes. Silent or synonymous codon positions, which do not determine amino acid sequences of the encoded proteins, define mRNA secondary structure and stability and affect the rate of translation, folding and post-translational modifications of nascent polypeptides. The RNA level selection is acting on synonymous sites in both prokaryotes and eukaryotes and is more common than previously thought. Selection pressure on the coding gene regions follows three-nucleotide periodic pattern of nucleotide base-pairing in mRNA, which is imposed by the genetic code. Synonymous positions of the coding regions have a higher level of hybridization potential relative to non-synonymous positions, and are multifunctional in their regulatory and structural roles. Recent experimental evidence and analysis of mRNA structure and interspecies conservation suggest that there is an evolutionary tradeoff between selective pressure acting at the RNA and protein levels. Here we provide a comprehensive overview of the studies that define the role of silent positions in regulating RNA structure and processing that exert downstream effects on proteins and their functions.
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Affiliation(s)
- Svetlana A Shabalina
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20984, USA.
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22
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Bicknell AA, Cenik C, Chua HN, Roth FP, Moore MJ. Introns in UTRs: why we should stop ignoring them. Bioessays 2012; 34:1025-34. [PMID: 23108796 DOI: 10.1002/bies.201200073] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although introns in 5'- and 3'-untranslated regions (UTRs) are found in many protein coding genes, rarely are they considered distinctive entities with specific functions. Indeed, mammalian transcripts with 3'-UTR introns are often assumed nonfunctional because they are subject to elimination by nonsense-mediated decay (NMD). Nonetheless, recent findings indicate that 5'- and 3'-UTR intron status is of significant functional consequence for the regulation of mammalian genes. Therefore these features should be ignored no longer.
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Affiliation(s)
- Alicia A Bicknell
- Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
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23
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Ezkurdia I, del Pozo A, Frankish A, Rodriguez JM, Harrow J, Ashman K, Valencia A, Tress ML. Comparative proteomics reveals a significant bias toward alternative protein isoforms with conserved structure and function. Mol Biol Evol 2012; 29:2265-83. [PMID: 22446687 PMCID: PMC3424414 DOI: 10.1093/molbev/mss100] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Advances in high-throughput mass spectrometry are making proteomics an increasingly important tool in genome annotation projects. Peptides detected in mass spectrometry experiments can be used to validate gene models and verify the translation of putative coding sequences (CDSs). Here, we have identified peptides that cover 35% of the genes annotated by the GENCODE consortium for the human genome as part of a comprehensive analysis of experimental spectra from two large publicly available mass spectrometry databases. We detected the translation to protein of “novel” and “putative” protein-coding transcripts as well as transcripts annotated as pseudogenes and nonsense-mediated decay targets. We provide a detailed overview of the population of alternatively spliced protein isoforms that are detectable by peptide identification methods. We found that 150 genes expressed multiple alternative protein isoforms. This constitutes the largest set of reliably confirmed alternatively spliced proteins yet discovered. Three groups of genes were highly overrepresented. We detected alternative isoforms for 10 of the 25 possible heterogeneous nuclear ribonucleoproteins, proteins with a key role in the splicing process. Alternative isoforms generated from interchangeable homologous exons and from short indels were also significantly enriched, both in human experiments and in parallel analyses of mouse and Drosophila proteomics experiments. Our results show that a surprisingly high proportion (almost 25%) of the detected alternative isoforms are only subtly different from their constitutive counterparts. Many of the alternative splicing events that give rise to these alternative isoforms are conserved in mouse. It was striking that very few of these conserved splicing events broke Pfam functional domains or would damage globular protein structures. This evidence of a strong bias toward subtle differences in CDS and likely conserved cellular function and structure is remarkable and strongly suggests that the translation of alternative transcripts may be subject to selective constraints.
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Affiliation(s)
- Iakes Ezkurdia
- Structural Biology and Biocomputing Programme, Spanish National Cancer Research Centre, Madrid, Spain
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24
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Kalyna M, Simpson CG, Syed NH, Lewandowska D, Marquez Y, Kusenda B, Marshall J, Fuller J, Cardle L, McNicol J, Dinh HQ, Barta A, Brown JWS. Alternative splicing and nonsense-mediated decay modulate expression of important regulatory genes in Arabidopsis. Nucleic Acids Res 2012; 40:2454-69. [PMID: 22127866 PMCID: PMC3315328 DOI: 10.1093/nar/gkr932] [Citation(s) in RCA: 327] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 09/22/2011] [Accepted: 10/10/2011] [Indexed: 11/26/2022] Open
Abstract
Alternative splicing (AS) coupled to nonsense-mediated decay (NMD) is a post-transcriptional mechanism for regulating gene expression. We have used a high-resolution AS RT-PCR panel to identify endogenous AS isoforms which increase in abundance when NMD is impaired in the Arabidopsis NMD factor mutants, upf1-5 and upf3-1. Of 270 AS genes (950 transcripts) on the panel, 102 transcripts from 97 genes (32%) were identified as NMD targets. Extrapolating from these data around 13% of intron-containing genes in the Arabidopsis genome are potentially regulated by AS/NMD. This cohort of naturally occurring NMD-sensitive AS transcripts also allowed the analysis of the signals for NMD in plants. We show the importance of AS in introns in 5' or 3'UTRs in modulating NMD-sensitivity of mRNA transcripts. In particular, we identified upstream open reading frames overlapping the main start codon as a new trigger for NMD in plants and determined that NMD is induced if 3'-UTRs were >350 nt. Unexpectedly, although many intron retention transcripts possess NMD features, they are not sensitive to NMD. Finally, we have shown that AS/NMD regulates the abundance of transcripts of many genes important for plant development and adaptation including transcription factors, RNA processing factors and stress response genes.
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Affiliation(s)
- Maria Kalyna
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Craig G. Simpson
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Naeem H. Syed
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Dominika Lewandowska
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Yamile Marquez
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Branislav Kusenda
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Jacqueline Marshall
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - John Fuller
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Linda Cardle
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Jim McNicol
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Huy Q. Dinh
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Andrea Barta
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - John W. S. Brown
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
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