1
|
Conn VM, Chinnaiyan AM, Conn SJ. Circular RNA in cancer. Nat Rev Cancer 2024:10.1038/s41568-024-00721-7. [PMID: 39075222 DOI: 10.1038/s41568-024-00721-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/13/2024] [Indexed: 07/31/2024]
Abstract
Over the past decade, circular RNA (circRNA) research has evolved into a bona fide research field shedding light on the functional consequence of this unique family of RNA molecules in cancer. Although the method of formation and the abundance of circRNAs can differ from their cognate linear mRNA, the spectrum of interacting partners and their resultant cellular functions in oncogenesis are analogous. However, with 10 times more diversity in circRNA variants compared with linear RNA variants, combined with their hyperstability in the cell, circRNAs are equipped to influence every stage of oncogenesis. This is an opportune time to address the breadth of circRNA in cancer focused on their spatiotemporal expression, mutations in biogenesis factors and contemporary functions through each stage of cancer. In this Review, we highlight examples of functional circRNAs in specific cancers, which satisfy critical criteria, including their physical co-association with the target and circRNA abundance at stoichiometrically valid quantities. These considerations are essential to develop strategies for the therapeutic exploitation of circRNAs as biomarkers and targeted anticancer agents.
Collapse
Affiliation(s)
- Vanessa M Conn
- Flinders Health and Medical Research Institute, College of Medicine and Public Health, Flinders University, South Australia, Australia
| | - Arul M Chinnaiyan
- Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, MI, USA
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Urology, University of Michigan, Ann Arbor, MI, USA
| | - Simon J Conn
- Flinders Health and Medical Research Institute, College of Medicine and Public Health, Flinders University, South Australia, Australia.
| |
Collapse
|
2
|
Poliseno L, Lanza M, Pandolfi PP. Coding, or non-coding, that is the question. Cell Res 2024:10.1038/s41422-024-00975-8. [PMID: 39054345 DOI: 10.1038/s41422-024-00975-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 04/30/2024] [Indexed: 07/27/2024] Open
Abstract
The advent of high-throughput sequencing uncovered that our genome is pervasively transcribed into RNAs that are seemingly not translated into proteins. It was also found that non-coding RNA transcripts outnumber canonical protein-coding genes. This mindboggling discovery prompted a surge in non-coding RNA research that started unraveling the functional relevance of these new genetic units, shaking the classic definition of "gene". While the non-coding RNA revolution was still taking place, polysome/ribosome profiling and mass spectrometry analyses revealed that peptides can be translated from non-canonical open reading frames. Therefore, it is becoming evident that the coding vs non-coding dichotomy is way blurrier than anticipated. In this review, we focus on several examples in which the binary classification of coding vs non-coding genes is outdated, since the same bifunctional gene expresses both coding and non-coding products. We discuss the implications of this intricate usage of transcripts in terms of molecular mechanisms of gene expression and biological outputs, which are often concordant, but can also surprisingly be discordant. Finally, we discuss the methodological caveats that are associated with the study of bifunctional genes, and we highlight the opportunities and challenges of therapeutic exploitation of this intricacy towards the development of anticancer therapies.
Collapse
Affiliation(s)
- Laura Poliseno
- Oncogenomics Unit, Core Research Laboratory, ISPRO, Pisa, Italy.
- Institute of Clinical Physiology, CNR, Pisa, Italy.
| | - Martina Lanza
- Oncogenomics Unit, Core Research Laboratory, ISPRO, Pisa, Italy
- Institute of Clinical Physiology, CNR, Pisa, Italy
- University of Siena, Siena, Italy
| | - Pier Paolo Pandolfi
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Turin, Torino, Italy.
- Renown Institute for Cancer, Nevada System of Higher Education, Reno, NV, USA.
| |
Collapse
|
3
|
Chang S, Ren D, Zhang L, Liu S, Yang W, Cheng H, Zhang X, Hong E, Geng D, Wang Y, Chen C, Zhang J, Shi T, Guo Y, Ni X, Wang H, Jin Y. Therapeutic SHPRH-146aa encoded by circ-SHPRH dynamically upregulates P21 to inhibit CDKs in neuroblastoma. Cancer Lett 2024; 598:217120. [PMID: 39002691 DOI: 10.1016/j.canlet.2024.217120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 07/03/2024] [Accepted: 07/10/2024] [Indexed: 07/15/2024]
Abstract
Recent research has underscored the significance of circular RNAs (circRNAs) in various cancers, including neuroblastoma (NB). Specifically, circ-SHPRH, a unique circRNA, has been revealed to inhibit tumor growth by sequestering miRNAs or producing the SHPRH-146aa protein. To explore circ-SHPRH's involvement in NB and its potential application in gene therapy, this study examined circ-SHPRH expression in 94 NB tissues and cell lines (SK-N-BE(2), SH-SY5Y) using real-time PCR and fluorescence in situ hybridization (FISH). Functional assays encompassing both overexpression and knockdown experiments in NB cell lines, as well as in vivo investigations, were conducted. RNA-seq analysis revealed a correlation between circ-SHPRH and the pathway of P21 (CDKN1A), a pivotal cell cycle regulator. Validation through PCR and other techniques confirmed that circ-SHPRH upregulated P21 expression. Furthermore, the regulatory role of circ-SHPRH in the P21-CDK pathway was corroborated through SHPRH-146aa expression analysis. Notably, adenovirus-mediated circ-SHPRH overexpression effectively curbed NB tumor growth in NSG mice, while combining circ-SHPRH with everolimus exhibited potential for NB treatment. This study elucidates the remarkable significance of circ-SHPRH in NB and its prospective utility in gene therapy, thereby paving the way for innovative therapeutic approaches.
Collapse
Affiliation(s)
- Saishuo Chang
- Department of Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Dong Ren
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, MOE Key Laboratory of Major Diseases in Children, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Li Zhang
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Shan Liu
- Department of Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Wei Yang
- Department of Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Haiyan Cheng
- Department of Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Xuexi Zhang
- Department of Otolaryngology, Head and Neck Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Enyu Hong
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, MOE Key Laboratory of Major Diseases in Children, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Di Geng
- Biobank for Clinical Data and Samples in Pediatrics, Beijing Children's Hospital, National Center for Children's Health, Beijing Pediatric Research Institute, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Yadi Wang
- Biobank for Clinical Data and Samples in Pediatrics, Beijing Children's Hospital, National Center for Children's Health, Beijing Pediatric Research Institute, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Chenghao Chen
- Department of Thoracic Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Jie Zhang
- Department of Otolaryngology, Head and Neck Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Tieliu Shi
- Center for Bioinformatics and Computational Biology and the Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Yongli Guo
- Department of Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Xin Ni
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, MOE Key Laboratory of Major Diseases in Children, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China; Department of Otolaryngology, Head and Neck Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China.
| | - Huanmin Wang
- Department of Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China.
| | - Yaqiong Jin
- Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, MOE Key Laboratory of Major Diseases in Children, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China.
| |
Collapse
|
4
|
Zhao H, Xiong Y, Zhou Z, Xu Q, Zi Y, Zheng X, Chen S, Xiao X, Gong L, Xu H, Liu L, Lu H, Cui Y, Shao S, Zhang J, Ma J, Zhou Q, Ma D, Li X. A hidden proteome encoded by circRNAs in human placentas: Implications for uncovering preeclampsia pathogenesis. Clin Transl Med 2024; 14:e1759. [PMID: 38997803 PMCID: PMC11245404 DOI: 10.1002/ctm2.1759] [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: 07/13/2023] [Revised: 06/21/2024] [Accepted: 06/25/2024] [Indexed: 07/14/2024] Open
Abstract
BACKGROUND CircRNA-encoded proteins (CEPs) are emerging as new players in health and disease, and function as baits for the common partners of their cognate linear-spliced RNA encoded proteins (LEPs). However, their prevalence across human tissues and biological roles remain largely unexplored. The placenta is an ideal model for identifying CEPs due to its considerable protein diversity that is required to sustain fetal development during pregnancy. The aim of this study was to evaluate circRNA translation in the human placenta, and the potential roles of the CEPs in placental development and dysfunction. METHODS Multiomics approaches, including RNA sequencing, ribosome profiling, and LC-MS/MS analysis, were utilised to identify novel translational events of circRNAs in human placentas. Bioinformatics methods and the protein bait hypothesis were employed to evaluate the roles of these newly discovered CEPs in placentation and associated disorders. The pathogenic role of a recently identified CEP circPRKCB119aa in preeclampsia was investigated through qRT-PCR, Western blotting, immunofluorescence imaging and phenotypic analyses. RESULTS We found that 528 placental circRNAs bound to ribosomes with active translational elongation, and 139 were translated to proteins. The CEPs showed considerable structural homology with their cognate LEPs, but are more stable, hydrophobic and have a lower molecular-weight than the latter, all of which are conducive to their function as baits. On this basis, CEPs are deduced to be closely involved in placental function. Furthermore, we focused on a novel CEP circPRKCB119aa, and illuminated its pathogenic role in preeclampsia; it enhanced trophoblast autophagy by acting as a bait to inhibit phosphorylation of the cognate linear isoform PKCβ. CONCLUSIONS We discovered a hidden circRNA-encoded proteome in the human placenta, which offers new insights into the mechanisms underlying placental development, as well as placental disorders such as preeclampsia. Key points A hidden circRNA-encoded proteome in the human placenta was extensively identified and systematically characterised. The circRNA-encoded proteins (CEPs) are potentially related to placental development and associated disorders. A novel conserved CEP circPRKCB119aa enhanced trophoblast autophagy by inhibiting phosphorylation of its cognate linear-spliced isoform protein kinase C (PKC) β in preeclampsia.
Collapse
Affiliation(s)
- Huanqiang Zhao
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
- Institute of Maternal and Child Medicine, Shenzhen Maternity and Child Healthcare Hospital, Shenzhen, Guangdong Province, China
| | - Yu Xiong
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Zixiang Zhou
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Qixin Xu
- Institute of Maternal and Child Medicine, Shenzhen Maternity and Child Healthcare Hospital, Shenzhen, Guangdong Province, China
| | - Yang Zi
- Institute of Maternal and Child Medicine, Shenzhen Maternity and Child Healthcare Hospital, Shenzhen, Guangdong Province, China
| | - Xiujie Zheng
- Institute of Maternal and Child Medicine, Shenzhen Maternity and Child Healthcare Hospital, Shenzhen, Guangdong Province, China
| | - Shiguo Chen
- Institute of Maternal and Child Medicine, Shenzhen Maternity and Child Healthcare Hospital, Shenzhen, Guangdong Province, China
| | - Xirong Xiao
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Lili Gong
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Huangfang Xu
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Lidong Liu
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Huiqing Lu
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Yutong Cui
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Shuyi Shao
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Jin Zhang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Jing Ma
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Qiongjie Zhou
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Duan Ma
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Xiaotian Li
- The Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
- Institute of Maternal and Child Medicine, Shenzhen Maternity and Child Healthcare Hospital, Shenzhen, Guangdong Province, China
| |
Collapse
|
5
|
Liu J, Zhao F, Chen LL, Su S. Dysregulation of circular RNAs in inflammation and cancers. FUNDAMENTAL RESEARCH 2023; 3:683-691. [PMID: 38933304 PMCID: PMC11197579 DOI: 10.1016/j.fmre.2023.04.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 02/24/2023] [Accepted: 04/19/2023] [Indexed: 06/28/2024] Open
Abstract
Emerging lines of evidence have shown that the production of the covalently closed single-stranded circular RNAs is not splicing errors, but rather a regulated process with distinct biogenesis and turnover. Circular RNAs are expressed in a cell type- and tissue-specific manner and often localize to specific subcellular regions or organelles for functions. The dysregulation of circular RNAs from birth to death is linked to the pathogenesis and progression of diverse diseases. This review outlines how aberrant circular RNA biogenesis, subcellular location, and degradation are linked to disease progression, focusing on metaflammation and cancers. We also discuss potential therapeutic strategies and obstacles in targeting such disease-related circular RNAs.
Collapse
Affiliation(s)
- Jiayu Liu
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
- Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Fangqing Zhao
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou 310003, China
| | - Ling-Ling Chen
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 200092, China
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou 310003, China
| | - Shicheng Su
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
- Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
- Department of Immunology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China
| |
Collapse
|
6
|
Pisignano G, Michael DC, Visal TH, Pirlog R, Ladomery M, Calin GA. Going circular: history, present, and future of circRNAs in cancer. Oncogene 2023; 42:2783-2800. [PMID: 37587333 PMCID: PMC10504067 DOI: 10.1038/s41388-023-02780-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 07/04/2023] [Accepted: 07/10/2023] [Indexed: 08/18/2023]
Abstract
To date, thousands of highly abundant and conserved single-stranded RNA molecules shaped into ring structures (circRNAs) have been identified. CircRNAs are multifunctional molecules that have been shown to regulate gene expression transcriptionally and post-transcriptionally and exhibit distinct tissue- and development-specific expression patterns associated with a variety of normal and disease conditions, including cancer pathogenesis. Over the past years, due to their intrinsic stability and resistance to ribonucleases, particular attention has been drawn to their use as reliable diagnostic and prognostic biomarkers in cancer diagnosis, treatment, and prevention. However, there are some critical caveats to their utility in the clinic. Their circular shape limits their annotation and a complete functional elucidation is lacking. This makes their detection and biomedical application still challenging. Herein, we review the current knowledge of circRNA biogenesis and function, and of their involvement in tumorigenesis and potential utility in cancer-targeted therapy.
Collapse
Affiliation(s)
- Giuseppina Pisignano
- Department of Life Sciences, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
| | - David C Michael
- Department of Life Sciences, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Tanvi H Visal
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Radu Pirlog
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Michael Ladomery
- Faculty of Health and Applied Sciences, University of the West of England, Coldharbour Lane, Frenchay, Bristol, BS16 1QY, UK
| | - George A Calin
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| |
Collapse
|
7
|
Deng Y, Zeng X, Lv Y, Qian Z, Guo P, Liu Y, Chen S. Cdyl2-60aa encoded by CircCDYL2 accelerates cardiomyocyte death by blocking APAF1 ubiquitination in rats. Exp Mol Med 2023; 55:860-869. [PMID: 37009805 PMCID: PMC10167378 DOI: 10.1038/s12276-023-00983-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 01/06/2023] [Accepted: 01/17/2023] [Indexed: 04/04/2023] Open
Abstract
The loss of cardiomyocytes (CMs) after myocardial infarction (MI) is widely acknowledged to initiate the development of heart failure (HF). Herein, we found that circCDYL2 (583 nt) derived from chromodomain Y-like 2 (Cdyl2) is significantly upregulated in vitro (oxygen-glucose deprivation (OGD)-treated CMs) and in vivo (failing heart post-MI) and can be translated into a polypeptide termed Cdyl2-60aa (~7 kDa) in the presence of internal ribosomal entry sites (IRES). Downregulation of circCDYL2 significantly decreased the loss of OGD-treated CMs or the infarcted area of the heart post-MI. Additionally, elevated circCDYL2 significantly accelerated CM apoptosis via Cdyl2-60aa. We then discovered that Cdyl2-60aa could stabilize protein apoptotic protease activating factor-1 (APAF1) and promote CM apoptosis; heat shock protein 70 (HSP70) mediated APAF1 degradation in CMs by ubiquitinating APAF1, which Cdyl2-60aa could competitively block. In conclusion, our work substantiated the claim that circCDYL2 could promote CM apoptosis via Cdyl2-60aa, which enhanced APAF1 stability by blocking its ubiquitination by HSP70, suggesting that it is a therapeutic target for HF post-MI in rats.
Collapse
Affiliation(s)
- Yunfei Deng
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Xiaochen Zeng
- Department of Clinical Laboratory, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Yifei Lv
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Zhiyuan Qian
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Peijie Guo
- Department of Functional Examination, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Yi Liu
- Department of Cell Biology, University of California, Davis, CA, USA
| | - Shaoliang Chen
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.
| |
Collapse
|
8
|
Rogalska ME, Vivori C, Valcárcel J. Regulation of pre-mRNA splicing: roles in physiology and disease, and therapeutic prospects. Nat Rev Genet 2023; 24:251-269. [PMID: 36526860 DOI: 10.1038/s41576-022-00556-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2022] [Indexed: 12/23/2022]
Abstract
The removal of introns from mRNA precursors and its regulation by alternative splicing are key for eukaryotic gene expression and cellular function, as evidenced by the numerous pathologies induced or modified by splicing alterations. Major recent advances have been made in understanding the structures and functions of the splicing machinery, in the description and classification of physiological and pathological isoforms and in the development of the first therapies for genetic diseases based on modulation of splicing. Here, we review this progress and discuss important remaining challenges, including predicting splice sites from genomic sequences, understanding the variety of molecular mechanisms and logic of splicing regulation, and harnessing this knowledge for probing gene function and disease aetiology and for the design of novel therapeutic approaches.
Collapse
Affiliation(s)
- Malgorzata Ewa Rogalska
- Genome Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Claudia Vivori
- Genome Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra (UPF), Barcelona, Spain
- The Francis Crick Institute, London, UK
| | - Juan Valcárcel
- Genome Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra (UPF), Barcelona, Spain.
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
| |
Collapse
|
9
|
Wu YL, Lou XJ, Fan YJ. Role of circRNAs in gastric cancer. Shijie Huaren Xiaohua Zazhi 2023; 31:85-91. [DOI: 10.11569/wcjd.v31.i3.85] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Circular RNAs (circRNAs) are a large class of non-coding RNAs with single-strand covalently closed loops, formed by reverse splicing, which widely exist in many cell lines and diverse species. Some circRNAs have highly evolutionarily conserved sequences, or tissue-specific or cell-specific expression patterns, and many circRNAs are extremely stable. In the past decades, accumulating evidence has indicated that circRNAs participate in the mechanisms associated with the development of many kinds of tumors, exert important biological functions by acting as microRNA or protein ‘sponges’, transcriptional regulatory factors, and protein translation templates, and play key roles in the occurrence and development of gastric cancer. This review comprehensively summarizes the biogenesis, characteristics, and biological functions of circRNAs, and the molecular mechanisms underlying the role of circRNAs in the carcinogenesis and progression of gastric cancer.
Collapse
Affiliation(s)
- Yu-Lin Wu
- The Fourth Clinical College of Zhejiang Chinese Medicine University, Hangzhou 310053, Zhejiang Province, China
| | - Xiao-Jun Lou
- Jiaxing Hospital of T.C.M, Jiaxing 314000, Zhejiang Province, China
| | - Yi-Jing Fan
- The Fourth Clinical College of Zhejiang Chinese Medicine University, Hangzhou 310053, Zhejiang Province, China
| |
Collapse
|
10
|
Wei H, Yang S, Yi T, Xu X, Liu C, Shen C, Guo Y, Li Q, Jin P. CircAGK regulates high dihydrotestosterone-induced apoptosis in DPCs through the miR-3180-5p/BAX axis. FASEB J 2023; 37:e22728. [PMID: 36607259 DOI: 10.1096/fj.202200849r] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 10/28/2022] [Accepted: 12/12/2022] [Indexed: 01/07/2023]
Abstract
The incidence of androgen alopecia (AGA), also known as seborrheic alopecia, has surged in recent years, and onset is occurring at younger ages. Dermal papilla cells (DPCs) are key to maintaining hair cycling, and apoptosis-driven processes in DPCs are closely related to hair follicle regeneration. Circular RNAs (circRNAs) are widely present in the human body and are closely related to the occurrence and development of many diseases. Currently, the biological functions of circRNAs in AGA are largely unknown. Whole-transcriptome sequencing was used to screen differential circRNA expression profiles between AGA patients and non-AGA patients. We found that hsa_circ_0002980 (circAGK) was significantly highly expressed in the AGA group. CircAGK promoted DPC apoptosis in the presence of high dihydrotestosterone (DHT) (15 nmol/L). By regulating the miR-3180-5p/BAX axis, circAGK promotes DPC apoptosis in a high DHT environment in vitro and inhibits hair growth in AGA mice in vivo, indicating that circAGK is a potential target for the clinical treatment of AGA.
Collapse
Affiliation(s)
- Hanxiao Wei
- Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Shuai Yang
- The First College of Clinical Medicine, Xuzhou Medical University, Xuzhou, China
| | - Tian Yi
- The First College of Clinical Medicine, Xuzhou Medical University, Xuzhou, China
| | - Xiaoyu Xu
- The First College of Clinical Medicine, Xuzhou Medical University, Xuzhou, China
| | - Chang Liu
- The First College of Clinical Medicine, Xuzhou Medical University, Xuzhou, China
| | - Caiqi Shen
- Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Yanping Guo
- Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Qiang Li
- Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Peisheng Jin
- Department of Plastic Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| |
Collapse
|
11
|
Sun X, Kang Y, Li M, Li Y, Song J. The emerging regulatory mechanisms and biological function of circular RNAs in skeletal muscle development. BIOCHIMICA ET BIOPHYSICA ACTA (BBA) - GENE REGULATORY MECHANISMS 2022; 1865:194888. [DOI: 10.1016/j.bbagrm.2022.194888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 10/13/2022] [Accepted: 10/15/2022] [Indexed: 11/07/2022]
|
12
|
Abstract
Covalently closed, single-stranded circular RNAs can be produced from viral RNA genomes as well as from the processing of cellular housekeeping noncoding RNAs and precursor messenger RNAs. Recent transcriptomic studies have surprisingly uncovered that many protein-coding genes can be subjected to backsplicing, leading to widespread expression of a specific type of circular RNAs (circRNAs) in eukaryotic cells. Here, we discuss experimental strategies used to discover and characterize diverse circRNAs at both the genome and individual gene scales. We further highlight the current understanding of how circRNAs are generated and how the mature transcripts function. Some circRNAs act as noncoding RNAs to impact gene regulation by serving as decoys or competitors for microRNAs and proteins. Others form extensive networks of ribonucleoprotein complexes or encode functional peptides that are translated in response to certain cellular stresses. Overall, circRNAs have emerged as an important class of RNAmolecules in gene expression regulation that impact many physiological processes, including early development, immune responses, neurogenesis, and tumorigenesis.
Collapse
Affiliation(s)
- Li Yang
- Center for Molecular Medicine, Children's Hospital, Fudan University and Shanghai Key Laboratory of Medical Epigenetics, International Laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University, Shanghai, China;
| | - Jeremy E Wilusz
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Therapeutic Innovation Center, Baylor College of Medicine, Houston, Texas, USA;
| | - Ling-Ling Chen
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China;
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China
| |
Collapse
|
13
|
Nielsen AF, Bindereif A, Bozzoni I, Hanan M, Hansen TB, Irimia M, Kadener S, Kristensen LS, Legnini I, Morlando M, Jarlstad Olesen MT, Pasterkamp RJ, Preibisch S, Rajewsky N, Suenkel C, Kjems J. Best practice standards for circular RNA research. Nat Methods 2022; 19:1208-1220. [PMID: 35618955 PMCID: PMC9759028 DOI: 10.1038/s41592-022-01487-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 03/16/2022] [Indexed: 12/26/2022]
Abstract
Circular RNAs (circRNAs) are formed in all domains of life and via different mechanisms. There has been an explosion in the number of circRNA papers in recent years; however, as a relatively young field, circRNA biology has an urgent need for common experimental standards for isolating, analyzing, expressing and depleting circRNAs. Here we propose a set of guidelines for circRNA studies based on the authors' experience. This Perspective will specifically address the major class of circRNAs in Eukarya that are generated by a spliceosome-catalyzed back-splicing event. We hope that the implementation of best practice principles for circRNA research will help move the field forward and allow a better functional understanding of this fascinating group of RNAs.
Collapse
Affiliation(s)
- Anne F Nielsen
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus, Denmark
| | - Albrecht Bindereif
- Department of Biology and Chemistry, Institute of Biochemistry, Justus Liebig University of Giessen, Giessen, Germany
| | - Irene Bozzoni
- Department of Biology and Biotechnology, Charles Darwin, and Center for Life Nano- & Neuro-Science, Fondazione Istituto Italiano di Tecnologia (IIT), Sapienza University of Rome, Rome, Italy
| | - Mor Hanan
- Department of Biological Chemistry, The Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Thomas B Hansen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
- TargoVax - Clinical Science, Oslo, Norway
| | - Manuel Irimia
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- ICREA, Barcelona, Spain
| | | | | | - Ivano Legnini
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Mariangela Morlando
- Department of Pharmaceutical Sciences, 'Department of Excellence 2018-2022', University of Perugia, Perugia, Italy
| | | | - R Jeroen Pasterkamp
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Stephan Preibisch
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- HHMI Janelia Research campus, Ashburn, VA, USA
| | - Nikolaus Rajewsky
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Christin Suenkel
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- Lonza - Drug Product Services, Basel, Switzerland
| | - Jørgen Kjems
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark.
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus, Denmark.
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
14
|
Abstract
In eukaryotic organisms, noncoding RNAs (ncRNAs) have been implicated as important regulators of multifaceted biological processes, including transcriptional, posttranscriptional, and epigenetic regulation of gene expression. In recent years, it is becoming clear that protozoan parasites encode diverse ncRNA transcripts; however, little is known about their cellular functions. Recent advances in high-throughput “omic” studies identified many novel long ncRNAs (lncRNAs) in apicomplexan parasites, some of which undergo splicing, polyadenylation, and encode small proteins. To date, only a few of them are characterized, leaving a big gap in our understanding regarding their origin, mode of action, and functions in parasite biology. In this review, we focus on lncRNAs of the human malaria parasite Plasmodium falciparum and highlight their cellular functions and possible mechanisms of action.
Collapse
Affiliation(s)
- Karina Simantov
- Department of Microbiology & Molecular Genetics, The Kuvin Center for the Study of Infectious and Tropical Diseases, IMRIC, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Manish Goyal
- Department of Microbiology & Molecular Genetics, The Kuvin Center for the Study of Infectious and Tropical Diseases, IMRIC, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Ron Dzikowski
- Department of Microbiology & Molecular Genetics, The Kuvin Center for the Study of Infectious and Tropical Diseases, IMRIC, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
- * E-mail:
| |
Collapse
|
15
|
Liu CX, Chen LL. Circular RNAs: Characterization, cellular roles, and applications. Cell 2022; 185:2016-2034. [PMID: 35584701 DOI: 10.1016/j.cell.2022.04.021] [Citation(s) in RCA: 331] [Impact Index Per Article: 165.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/11/2022] [Accepted: 04/13/2022] [Indexed: 02/07/2023]
Abstract
Most circular RNAs are produced from the back-splicing of exons of precursor mRNAs. Recent technological advances have in part overcome problems with their circular conformation and sequence overlap with linear cognate mRNAs, allowing a better understanding of their cellular roles. Depending on their localization and specific interactions with DNA, RNA, and proteins, circular RNAs can modulate transcription and splicing, regulate stability and translation of cytoplasmic mRNAs, interfere with signaling pathways, and serve as templates for translation in different biological and pathophysiological contexts. Emerging applications of RNA circles to interfere with cellular processes, modulate immune responses, and direct translation into proteins shed new light on biomedical research. In this review, we discuss approaches used in circular RNA studies and the current understanding of their regulatory roles and potential applications.
Collapse
Affiliation(s)
- Chu-Xiao Liu
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
| | - Ling-Ling Chen
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China; School of Life Science and Technology, ShanghaiTech University, Shanghai, China; School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China.
| |
Collapse
|
16
|
Wen SY, Qadir J, Yang BB. Circular RNA translation: novel protein isoforms and clinical significance. Trends Mol Med 2022; 28:405-420. [DOI: 10.1016/j.molmed.2022.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/08/2022] [Accepted: 03/09/2022] [Indexed: 02/07/2023]
|
17
|
Kristensen LS, Jakobsen T, Hager H, Kjems J. The emerging roles of circRNAs in cancer and oncology. Nat Rev Clin Oncol 2022; 19:188-206. [PMID: 34912049 DOI: 10.1038/s41571-021-00585-y] [Citation(s) in RCA: 448] [Impact Index Per Article: 224.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2021] [Indexed: 12/14/2022]
Abstract
Over the past decade, circular RNAs (circRNAs) have emerged as a large class of primarily non-coding RNA molecules, many of which have key roles in cancer development and progression through diverse mechanisms of action. CircRNAs often have tissue-restricted and cancer-specific expression patterns, and accumulating data suggest that these molecules are of potential clinical relevance and utility. In particular, circRNAs have strong potential as diagnostic, prognostic and predictive biomarkers, which is underscored by their detectability in liquid biopsy samples such as in plasma, saliva and urine. However, technical issues in the detection and assessment of circRNAs as well as biological knowledge gaps need to be addressed to move this relatively young field of research forward and bring circRNAs to the forefront of clinical practice. Herein, we review the current knowledge regarding circRNA biogenesis, regulation and functions in cancer as well as their clinical potential as biomarkers, therapeutic agents and drug targets.
Collapse
Affiliation(s)
| | | | - Henrik Hager
- Department of Clinical Pathology, Vejle Hospital, Vejle, Denmark.,Danish Colorectal Cancer Center South, Vejle Hospital, Vejle, Denmark
| | - Jørgen Kjems
- Department of Molecular Biology and Genetics (MBG), Aarhus University, Aarhus C, Denmark. .,Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark.
| |
Collapse
|
18
|
Chen L, Huang C, Shan G. Circular RNAs in physiology and non-immunological diseases. Trends Biochem Sci 2021; 47:250-264. [PMID: 34865956 DOI: 10.1016/j.tibs.2021.11.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 11/04/2021] [Accepted: 11/08/2021] [Indexed: 12/27/2022]
Abstract
Circular RNAs (circRNAs) are covalently closed single-stranded RNAs. Four subclasses of circRNAs have been identified in animal cells, and they have unique features in their biogenesis, degradation, and transport. CircRNAs have diverse molecular functions in sponging miRNAs, regulating transcription, modulating RNA-binding proteins, and even encoding proteins. Some circRNAs are important regulators of various physiological processes to maintain homeostasis. Dysregulation of circRNAs is associated with human disorders, and individual circRNAs are crucial factors that contribute to major diseases including non-immunological diseases such as cancers, neurological disorders, cardiovascular disease, and metabolic disease. Debates on circRNAs have also been raised in recent years, and further studies would help to resolve these disputes and potentially lead to biomedical applications of circRNAs.
Collapse
Affiliation(s)
- Liang Chen
- Department of Clinical Laboratory, First Affiliated Hospital of the USTC, Hefei National Laboratory for Physical Sciences at Microscale, Chinese Academy of Sciences (CAS) Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China (UTSC), Hefei, 230027, China
| | - Chuan Huang
- School of Life Sciences, Chongqing University, Chongqing 401331, China; Center of Plant Functional Genomics, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing 401331, China.
| | - Ge Shan
- Department of Clinical Laboratory, First Affiliated Hospital of the USTC, Hefei National Laboratory for Physical Sciences at Microscale, Chinese Academy of Sciences (CAS) Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China (UTSC), Hefei, 230027, China; Sir Run-Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China.
| |
Collapse
|
19
|
Chen LL, Wilusz JE. Methods for circular RNAs. Methods 2021; 196:1-2. [PMID: 34601050 DOI: 10.1016/j.ymeth.2021.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
20
|
Rahimi K, Færch Nielsen A, Venø MT, Kjems J. Nanopore long-read sequencing of circRNAs. Methods 2021; 196:23-29. [PMID: 34571139 DOI: 10.1016/j.ymeth.2021.09.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/15/2021] [Accepted: 09/22/2021] [Indexed: 12/30/2022] Open
Abstract
Circular RNA (circRNA) is a group of highly stable RNA molecules with suggested roles in development and disease. They derive from linear pre-mRNAs when a 5'-splice site splices back to an upstream 3'-splice site in a process termed back-splicing. Most circRNAs are multi-exonic and may contain several thousand nucleotides. The extensive sequence overlap between the linear and circular forms of an RNA means that circRNA identification depends on the detection of back-splice-junction sequence reads that are unique to the circRNA. However, the short-read length obtained using standard next-generation sequencing techniques means that the internal sequence, exon composition and alternative splicing of circRNAs are unknown in many cases. Recently, several labs, including ours, have reported protocols for sequencing of circRNAs using long-read nanopore sequencing and thereby expanded our understanding of circRNA size distribution and internal splicing patterns. Here, we review these protocols and discuss the different approaches taken to study the full length composition of circRNAs.
Collapse
Affiliation(s)
- Karim Rahimi
- Department of Molecular Biology and Genetics (MBG), Aarhus University, DK-8000 Aarhus, Denmark; Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus, Denmark.
| | - Anne Færch Nielsen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus, Denmark; Center for Cellular signal Patterns (CellPAT), Aarhus University, DK-8000 Aarhus, Denmark
| | | | - Jørgen Kjems
- Department of Molecular Biology and Genetics (MBG), Aarhus University, DK-8000 Aarhus, Denmark; Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus, Denmark; Center for Cellular signal Patterns (CellPAT), Aarhus University, DK-8000 Aarhus, Denmark.
| |
Collapse
|
21
|
Rahimi K, Venø MT, Dupont DM, Kjems J. Nanopore sequencing of brain-derived full-length circRNAs reveals circRNA-specific exon usage, intron retention and microexons. Nat Commun 2021; 12:4825. [PMID: 34376658 PMCID: PMC8355340 DOI: 10.1038/s41467-021-24975-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 07/16/2021] [Indexed: 12/17/2022] Open
Abstract
Circular RNA (circRNA) is a class of covalently joined non-coding RNAs with functional roles in a wide variety of cellular processes. Their composition shows extensive overlap with exons found in linear mRNAs making it difficult to delineate their composition using short-read RNA sequencing, particularly for long and multi-exonic circRNAs. Here, we use long-read nanopore sequencing of nicked circRNAs (circNick-LRS) and characterize a total of 18,266 and 39,623 circRNAs in human and mouse brain, respectively. We further develop an approach for targeted long-read sequencing of a panel of circRNAs (circPanel-LRS), eliminating the need for prior circRNA enrichment and find >30 circRNA isoforms on average per targeted locus. Our data show that circRNAs exhibit a large number of splicing events such as novel exons, intron retention and microexons that preferentially occur in circRNAs. We propose that altered exon usage in circRNAs may reflect resistance to nonsense-mediated decay in the absence of translation.
Collapse
Affiliation(s)
- Karim Rahimi
- Department of Molecular Biology and Genetics (MBG), Aarhus University, Aarhus, Denmark.
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark.
| | - Morten T Venø
- Department of Molecular Biology and Genetics (MBG), Aarhus University, Aarhus, Denmark
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark
- Omiics ApS, Aarhus, Denmark
| | - Daniel M Dupont
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark
| | - Jørgen Kjems
- Department of Molecular Biology and Genetics (MBG), Aarhus University, Aarhus, Denmark.
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark.
| |
Collapse
|
22
|
Jiang Y, Chen X, Zhang W. Overexpression-based detection of translatable circular RNAs is vulnerable to coexistent linear RNA byproducts. Biochem Biophys Res Commun 2021; 558:189-195. [PMID: 33940551 DOI: 10.1016/j.bbrc.2021.04.044] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 04/12/2021] [Indexed: 12/11/2022]
Abstract
In RNA field, the demarcation between coding and non-coding has been negotiated by the recent discovery of occasionally translated circular RNAs (circRNAs). Although absent of 5' cap structure, circRNAs can be translated cap-independently. Complementary intron-mediated overexpression is one of the most utilized methodologies for circRNA research but not without bearing echoing skepticism for its poorly defined mechanism and latent coexistent side products. In this study, leveraging such circRNA overexpression system, we have interrogated the protein-coding potential of 30 human circRNAs containing infinite open reading frames in HEK293T cells. Surprisingly, pervasive translation signals are detected by immunoblotting. However, intensive mutagenesis reveals that numerous translation signals are generated independently of circRNA synthesis. We have developed a dual tag strategy to isolate translation noise and directly demonstrate that the spurious translation signals originate from cryptically spliced linear transcripts. The concomitant linear RNA byproducts, presumably concatemers, can be translated to allow pseudo rolling circle translation signals, and can involve backsplicing junction (BSJ) to disqualify the BSJ-based evidence for circRNA translation. We also find non-AUG start codons may engage in the translation initiation of circRNAs. Taken together, our systematic evaluation sheds light on heterogeneous translational outputs from circRNA overexpression vector and comes with a caveat that ectopic overexpression technique necessitates extremely rigorous control setup in circRNA translation and functional investigation.
Collapse
Affiliation(s)
- Yanyi Jiang
- Biomedical Research Institute, Shenzhen Peking University - The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong Province, China.
| | - Xiaofan Chen
- Biomedical Research Institute, Shenzhen Peking University - The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong Province, China
| | - Wei Zhang
- Biomedical Research Institute, Shenzhen Peking University - The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong Province, China; Greater Bay Biomedical Innocenter, Shenzhen Bay Laboratory, Shenzhen, Guangdong Province, China.
| |
Collapse
|