1
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Hwang HJ, Kim YK. Molecular mechanisms of circular RNA translation. Exp Mol Med 2024:10.1038/s12276-024-01220-3. [PMID: 38871818 DOI: 10.1038/s12276-024-01220-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 02/22/2024] [Accepted: 02/23/2024] [Indexed: 06/15/2024] Open
Abstract
Circular RNAs (circRNAs) are covalently closed single-stranded RNAs without a 5' cap structure and a 3' poly(A) tail typically present in linear mRNAs of eukaryotic cells. CircRNAs are predominantly generated through a back-splicing process within the nucleus. CircRNAs have long been considered non-coding RNAs seemingly devoid of protein-coding potential. However, many recent studies have challenged this idea and have provided substantial evidence that a subset of circRNAs can associate with polysomes and indeed be translated. Therefore, in this review, we primarily highlight the 5' cap-independent internal initiation of translation that occurs on circular RNAs. Several molecular features of circRNAs, including the internal ribosome entry site, N6-methyladenosine modification, and the exon junction complex deposited around the back-splicing junction after back-splicing event, play pivotal roles in their efficient internal translation. We also propose a possible relationship between the translatability of circRNAs and their stability, with a focus on nonsense-mediated mRNA decay and nonstop decay, both of which are well-characterized mRNA surveillance mechanisms. An in-depth understanding of circRNA translation will reshape and expand our current knowledge of proteomics.
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Affiliation(s)
- Hyun Jung Hwang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Yoon Ki Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.
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2
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Sachdev A, Gill K, Sckaff M, Birk AM, Aladesuyi Arogundade O, Brown KA, Chouhan RS, Issagholian-Lewin PO, Patel E, Watry HL, Bernardi MT, Keough KC, Tsai YC, Smith AST, Conklin BR, Clelland CD. Reversal of C9orf72 mutation-induced transcriptional dysregulation and pathology in cultured human neurons by allele-specific excision. Proc Natl Acad Sci U S A 2024; 121:e2307814121. [PMID: 38621131 PMCID: PMC11047104 DOI: 10.1073/pnas.2307814121] [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: 05/09/2023] [Accepted: 03/01/2024] [Indexed: 04/17/2024] Open
Abstract
Efforts to genetically reverse C9orf72 pathology have been hampered by our incomplete understanding of the regulation of this complex locus. We generated five different genomic excisions at the C9orf72 locus in a patient-derived induced pluripotent stem cell (iPSC) line and a non-diseased wild-type (WT) line (11 total isogenic lines), and examined gene expression and pathological hallmarks of C9 frontotemporal dementia/amyotrophic lateral sclerosis in motor neurons differentiated from these lines. Comparing the excisions in these isogenic series removed the confounding effects of different genomic backgrounds and allowed us to probe the effects of specific genomic changes. A coding single nucleotide polymorphism in the patient cell line allowed us to distinguish transcripts from the normal vs. mutant allele. Using digital droplet PCR (ddPCR), we determined that transcription from the mutant allele is upregulated at least 10-fold, and that sense transcription is independently regulated from each allele. Surprisingly, excision of the WT allele increased pathologic dipeptide repeat poly-GP expression from the mutant allele. Importantly, a single allele was sufficient to supply a normal amount of protein, suggesting that the C9orf72 gene is haplo-sufficient in induced motor neurons. Excision of the mutant repeat expansion reverted all pathology (RNA abnormalities, dipeptide repeat production, and TDP-43 pathology) and improved electrophysiological function, whereas silencing sense expression did not eliminate all dipeptide repeat proteins, presumably because of the antisense expression. These data increase our understanding of C9orf72 gene regulation and inform gene therapy approaches, including antisense oligonucleotides (ASOs) and CRISPR gene editing.
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Affiliation(s)
| | - Kamaljot Gill
- Gladstone Institutes, San Francisco, CA94158
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
| | - Maria Sckaff
- Gladstone Institutes, San Francisco, CA94158
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
| | | | - Olubankole Aladesuyi Arogundade
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | - Katherine A. Brown
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | - Runvir S. Chouhan
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | - Patrick Oliver Issagholian-Lewin
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | - Esha Patel
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
| | | | | | | | | | - Alec Simon Tulloch Smith
- Department of Physiology and Biophysics, University of Washington, Seattle, WA98195
- The Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA98195
| | - Bruce R. Conklin
- Gladstone Institutes, San Francisco, CA94158
- Department of Medicine, University of California San Francisco, San Francisco, CA94143
- Department of Ophthalmology, University of California San Francisco, San Francisco, CA94143
- Department of Pharmacology, University of California San Francisco, San Francisco, CA94158
| | - Claire Dudley Clelland
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA94158
- Memory & Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA94158
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3
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Blake LA, Watkins L, Liu Y, Inoue T, Wu B. A rapid inducible RNA decay system reveals fast mRNA decay in P-bodies. Nat Commun 2024; 15:2720. [PMID: 38548718 PMCID: PMC10979015 DOI: 10.1038/s41467-024-46943-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 03/14/2024] [Indexed: 04/01/2024] Open
Abstract
RNA decay is vital for regulating mRNA abundance and gene expression. Existing technologies lack the spatiotemporal precision or transcript specificity to capture the stochastic and transient decay process. We devise a general strategy to inducibly recruit protein factors to modulate target RNA metabolism. Specifically, we introduce a Rapid Inducible Decay of RNA (RIDR) technology to degrade target mRNAs within minutes. The fast and synchronous induction enables direct visualization of mRNA decay dynamics in cells. Applying RIDR to endogenous ACTB mRNA reveals rapid formation and dissolution of RNA granules in pre-existing P-bodies. Time-resolved RNA distribution measurements demonstrate rapid RNA decay inside P-bodies, which is further supported by knocking down P-body constituent proteins. Light and oxidative stress modulate P-body behavior, potentially reconciling the contradictory literature about P-body function. This study reveals compartmentalized RNA decay kinetics, establishing RIDR as a pivotal tool for exploring the spatiotemporal RNA metabolism in cells.
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Affiliation(s)
- Lauren A Blake
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- The Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Leslie Watkins
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- The Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Yang Liu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- The Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Biochemistry, University of Utah, Salt Lake City, UT, 84112, USA
| | - Takanari Inoue
- The Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Bin Wu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- The Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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4
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Blake LA, De La Cruz A, Wu B. Imaging spatiotemporal translation regulation in vivo. Semin Cell Dev Biol 2024; 154:155-164. [PMID: 36963991 PMCID: PMC10514244 DOI: 10.1016/j.semcdb.2023.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 03/08/2023] [Accepted: 03/15/2023] [Indexed: 03/26/2023]
Abstract
Translation is regulated spatiotemporally to direct protein synthesis when and where it is needed. RNA localization and local translation have been observed in various subcellular compartments, allowing cells to rapidly and finely adjust their proteome post-transcriptionally. Local translation on membrane-bound organelles is important to efficiently synthesize proteins targeted to the organelles. Protein-RNA phase condensates restrict RNA spatially in membraneless organelles and play essential roles in translation regulation and RNA metabolism. In addition, the temporal translation kinetics not only determine the amount of protein produced, but also serve as an important checkpoint for the quality of ribosomes, mRNAs, and nascent proteins. Translation imaging provides a unique capability to study these fundamental processes in the native environment. Recent breakthroughs in imaging enabled real-time visualization of translation of single mRNAs, making it possible to determine the spatial distribution and key biochemical parameters of in vivo translation dynamics. Here we reviewed the recent advances in translation imaging methods and their applications to study spatiotemporal translation regulation in vivo.
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Affiliation(s)
- Lauren A Blake
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ana De La Cruz
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Bin Wu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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5
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Zhou M, Li S, Huang C. Physiological and pathological functions of circular RNAs in the nervous system. Neural Regen Res 2024; 19:342-349. [PMID: 37488888 PMCID: PMC10503630 DOI: 10.4103/1673-5374.379017] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/20/2023] [Accepted: 05/29/2023] [Indexed: 07/26/2023] Open
Abstract
Circular RNAs (circRNAs) are a class of covalently closed single-stranded RNAs that are expressed during the development of specific cells and tissues. CircRNAs play crucial roles in physiological and pathological processes by sponging microRNAs, modulating gene transcription, controlling the activity of certain RNA-binding proteins, and producing functional peptides. A key focus of research at present is the functionality of circRNAs in the nervous system and several advances have emerged over the last 2 years. However, the precise role of circRNAs in the nervous system has yet to be comprehensively reviewed. In this review, we first summarize the recently described roles of circRNAs in brain development, maturity, and aging. Then, we focus on the involvement of circRNAs in various diseases of the central nervous system, such as brain cancer, chronic neurodegenerative diseases, acute injuries of the nervous system, and neuropathic pain. A better understanding of the functionality of circRNAs will help us to develop potential diagnostic, prognostic, and therapeutic strategies to treat diseases of the nervous system.
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Affiliation(s)
- Min Zhou
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Shi Li
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Chuan Huang
- School of Life Sciences, Chongqing University, Chongqing, China
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6
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Zheng Z, Zeng X, Zhu Y, Leng M, Zhang Z, Wang Q, Liu X, Zeng S, Xiao Y, Hu C, Pang S, Wang T, Xu B, Peng P, Li F, Tan W. CircPPAP2B controls metastasis of clear cell renal cell carcinoma via HNRNPC-dependent alternative splicing and targeting the miR-182-5p/CYP1B1 axis. Mol Cancer 2024; 23:4. [PMID: 38184608 PMCID: PMC10770969 DOI: 10.1186/s12943-023-01912-w] [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: 10/02/2023] [Accepted: 12/07/2023] [Indexed: 01/08/2024] Open
Abstract
BACKGROUND Renal cell carcinoma (RCC) is one of the most common malignant tumor worldwide. Metastasis is a leading case of cancer-related deaths of RCC. Circular RNAs (circRNAs), a class of noncoding RNAs, have emerged as important regulators in cancer metastasis. However, the functional effects and regulatory mechanisms of circRNAs on RCC metastasis remain largely unknown. METHODS High-throughput RNA sequencing techniques were performed to analyze the expression profiles of circRNAs and mRNAs in highly and poorly invasive clear cell renal cell carcinoma (ccRCC) cell lines. Functional experiments were performed to unveil the regulatory role of circPPAP2B in the proliferation and metastatic capabilities of ccRCC cells. RNA pulldown, Mass spectrometry analysis, RNA methylation immunoprecipitation (MeRIP), RNA immunoprecipitation (RIP), co-immunoprecipitation (CoIP), next-generation RNA-sequencing and double luciferase experiments were employed to clarify the molecular mechanisms by which circPPAP2B promotes ccRCC metastasis. RESULTS In this study, we describe a newly identified circular RNA called circPPAP2B, which is overexpressed in highly invasive ccRCC cells, as determined through advanced high-throughput RNA sequencing techniques. Furthermore, we observed elevated circPPAP2B in ccRCC tissues, particularly in metastatic ccRCC tissues, and found it to be associated with poor prognosis. Functional experiments unveiled that circPPAP2B actively stimulates the proliferation and metastatic capabilities of ccRCC cells. Mechanistically, circPPAP2B interacts with HNRNPC in a m6A-dependent manner to facilitate HNRNPC nuclear translocation. Subcellular relocalization was dependent upon nondegradable ubiquitination of HNRNPC and stabilization of an HNRNPC/Vimentin/Importin α7 ternary complex. Moreover, we found that circPPAP2B modulates the interaction between HNRNPC and splicing factors, PTBP1 and HNPNPK, and regulates pre-mRNA alternative splicing. Finally, our studies demonstrate that circPPAP2B functions as a miRNA sponge to directly bind to miR-182-5p and increase CYP1B1 expression in ccRCC. CONCLUSIONS Collectively, our study provides comprehensive evidence that circPPAP2B promotes proliferation and metastasis of ccRCC via HNRNPC-dependent alternative splicing and miR-182-5p/CYP1B1 axis and highlights circPPAP2B as a potential therapeutic target for ccRCC intervention.
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Affiliation(s)
- Zaosong Zheng
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Xiangbo Zeng
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Yuanchao Zhu
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Mengxin Leng
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Zhiyong Zhang
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Qiong Wang
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Xiaocen Liu
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Siying Zeng
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Yongyuan Xiao
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Chenxi Hu
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Shiyu Pang
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Tong Wang
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Bihong Xu
- Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Peidan Peng
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Fei Li
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China.
| | - Wanlong Tan
- Department of Urology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China.
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7
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Ito H, Machida K, Hasumi M, Ueyama M, Nagai Y, Imataka H, Taguchi H. Reconstitution of C9orf72 GGGGCC repeat-associated non-AUG translation with purified human translation factors. Sci Rep 2023; 13:22826. [PMID: 38129650 PMCID: PMC10739749 DOI: 10.1038/s41598-023-50188-z] [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: 08/28/2023] [Accepted: 12/16/2023] [Indexed: 12/23/2023] Open
Abstract
Nucleotide repeat expansion of GGGGCC (G4C2) in the non-coding region of C9orf72 is the most common genetic cause underlying amyotrophic lateral sclerosis and frontotemporal dementia. Transcripts harboring this repeat expansion undergo the translation of dipeptide repeats via a non-canonical process known as repeat-associated non-AUG (RAN) translation. In order to ascertain the essential components required for RAN translation, we successfully recapitulated G4C2-RAN translation using an in vitro reconstituted translation system comprising human factors, namely the human PURE system. Our findings conclusively demonstrate that the presence of fundamental translation factors is sufficient to mediate the elongation from the G4C2 repeat. Furthermore, the initiation mechanism proceeded in a 5' cap-dependent manner, independent of eIF2A or eIF2D. In contrast to cell lysate-mediated RAN translation, where longer G4C2 repeats enhanced translation, we discovered that the expansion of the G4C2 repeats inhibited translation elongation using the human PURE system. These results suggest that the repeat RNA itself functions as a repressor of RAN translation. Taken together, our utilization of a reconstituted RAN translation system employing minimal factors represents a distinctive and potent approach for elucidating the intricacies underlying RAN translation mechanism.
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Grants
- JPMJFS2112 Japan Science and Technology Agency
- JP26116002 Ministry of Education, Culture, Sports, Science and Technology
- JP18H03984 Ministry of Education, Culture, Sports, Science and Technology
- JP21H04763 Ministry of Education, Culture, Sports, Science and Technology
- JP20H05925 Ministry of Education, Culture, Sports, Science and Technology
- 2019-25 Mitsubishi Foundation
- 2019 Uehara Memorial Foundation
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Affiliation(s)
- Hayato Ito
- School of Life Science and Technology, Tokyo Institute of Technology, S2-19, Nagatsuta 4259, Midori-ku, Yokohama, 226-8501, Japan
| | - Kodai Machida
- Graduate School of Engineering, University of Hyogo, Shosha, 2167, Himeji, Hyogo, 671-2280, Japan
| | - Mayuka Hasumi
- School of Life Science and Technology, Tokyo Institute of Technology, S2-19, Nagatsuta 4259, Midori-ku, Yokohama, 226-8501, Japan
| | - Morio Ueyama
- Department of Neurology, Faculty of Medicine, Kindai University, Ohonohigashi 377-2, Osaka-Sayama, 589-8511, Japan
| | - Yoshitaka Nagai
- Department of Neurology, Faculty of Medicine, Kindai University, Ohonohigashi 377-2, Osaka-Sayama, 589-8511, Japan
| | - Hiroaki Imataka
- Graduate School of Engineering, University of Hyogo, Shosha, 2167, Himeji, Hyogo, 671-2280, Japan
| | - Hideki Taguchi
- School of Life Science and Technology, Tokyo Institute of Technology, S2-19, Nagatsuta 4259, Midori-ku, Yokohama, 226-8501, Japan.
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, S2-19, Nagatsuta 4259, Midori-ku, Yokohama, 226-8501, Japan.
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Maltby CJ, Krans A, Grudzien SJ, Palacios Y, Muiños J, Suárez A, Asher M, Khurana V, Barmada SJ, Dijkstra AA, Todd PK. AAGGG repeat expansions trigger RFC1-independent synaptic dysregulation in human CANVAS Neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.13.571345. [PMID: 38168171 PMCID: PMC10760133 DOI: 10.1101/2023.12.13.571345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS) is a late onset, recessively inherited neurodegenerative disorder caused by biallelic, non-reference pentameric AAGGG(CCCTT) repeat expansions within the second intron of replication factor complex subunit 1 (RFC1). To investigate how these repeats cause disease, we generated CANVAS patient induced pluripotent stem cell (iPSC) derived neurons (iNeurons) and utilized calcium imaging and transcriptomic analysis to define repeat-elicited gain-of-function and loss-of-function contributions to neuronal toxicity. AAGGG repeat expansions do not alter neuronal RFC1 splicing, expression, or DNA repair pathway functions. In reporter assays, AAGGG repeats are translated into pentapeptide repeat proteins that selectively accumulate in CANVAS patient brains. However, neither these proteins nor repeat RNA foci were detected in iNeurons, and overexpression of these repeats in isolation did not induce neuronal toxicity. CANVAS iNeurons exhibit defects in neuronal development and diminished synaptic connectivity that is rescued by CRISPR deletion of a single expanded allele. These phenotypic deficits were not replicated by knockdown of RFC1 in control neurons and were not rescued by ectopic expression of RFC1. These findings support a repeat-dependent but RFC1-independent cause of neuronal dysfunction in CANVAS, with important implications for therapeutic development in this currently untreatable condition.
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Affiliation(s)
- Connor J. Maltby
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Amy Krans
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Ann Arbor Veterans Administration Healthcare, Ann Arbor, MI, USA
| | - Samantha J. Grudzien
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Yomira Palacios
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Postbaccalaureate Research Education Program, University of Michigan, Ann Arbor, MI, USA
| | - Jessica Muiños
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- UM SMART Undergraduate Summer Program, University of Michigan, Ann Arbor, MI, USA
| | - Andrea Suárez
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Postbaccalaureate Research Education Program, University of Michigan, Ann Arbor, MI, USA
| | - Melissa Asher
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Vikram Khurana
- Department of Neurology, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Sami J. Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Anke A. Dijkstra
- Department of Pathology, Amsterdam UMC, Amsterdam Neuroscience, Amsterdam, The Netherlands
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Peter K. Todd
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Ann Arbor Veterans Administration Healthcare, Ann Arbor, MI, USA
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9
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Zeng K, Peng J, Xing Y, Zhang L, Zeng P, Li W, Zhang W, Pan Z, Zhou C, Lin J. A positive feedback circuit driven by m 6A-modified circular RNA facilitates colorectal cancer liver metastasis. Mol Cancer 2023; 22:202. [PMID: 38087322 PMCID: PMC10717141 DOI: 10.1186/s12943-023-01848-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 08/23/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND Liver metastasis is the leading cause of death in patients with colorectal cancer (CRC). Emerge evidence suggests that circular RNA (circRNA) is a pivotal player in cancer progression. However, its role in CRC liver metastasis remains largely unknown. METHODS Circ-YAP expression was detected by qRT-PCR and in situ hybridization. The function of circ-YAP was tested by wound healing, transwell and CCK-8 assays. RNA immunoprecipitation, pull-down, luciferase reporter, chromatin immunoprecipitation assays were used to investigate the mechanism underlying circ-YAP promoting CRC liver metastasis. CRC liver metastasis animal model was established to assess the effect of circ-YAP in vivo. RESULTS Circ-YAP was notably upregulated in CRC with liver metastasis, which was associated with dismal prognosis. Circ-YAP promoted CRC cell migration and invasion in vitro, and facilitated liver metastasis in patient-derived xenografts (PDX) models in vivo. Mechanistically, circ-YAP encoded a novel truncated protein containing 220 amino acids, termed as YAP-220aa, which competitively bound to LATS1, resulting in YAP dephosphorylation and nuclear translocation, thereby activating a cohort of metastasis-promoting genes. Importantly, N6-methyladenosine (m6A) modification orchestrated efficient initiation of circ-YAP translation, requiring m6A reader YTHDF3 and eIF4G2 translation initiation complex. Intriguingly, circ-YAP was transcriptionally enhanced by YAP/TEAD complex, thus forming a positive regulatory feed-forward loop. CONCLUSIONS Our findings reveal a previously uncharacterized oncoprotein encoded by circ-YAP, implying a promising biomarker and therapeutic target for CRC patients with liver metastasis.
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Affiliation(s)
- Kaixuan Zeng
- Precision Medical Research Institute, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710000, China
| | - Jianhong Peng
- Department of Colorectal Surgery, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, Guangzhou, China
| | - Yue Xing
- 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
| | - Linjie Zhang
- Department of Colorectal Surgery, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, Guangzhou, China
| | - Peishan Zeng
- Department of Rehabilitation Medicine, The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510630, China
| | - Weihao Li
- Department of Colorectal Surgery, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, Guangzhou, China
| | - Weili Zhang
- Department of Colorectal Surgery, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, Guangzhou, China
| | - Zhizhong Pan
- Department of Colorectal Surgery, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China.
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, Guangzhou, China.
| | - Chi Zhou
- Department of Colorectal Surgery, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China.
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, Guangzhou, China.
| | - Junzhong Lin
- Department of Colorectal Surgery, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China.
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, Guangzhou, China.
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10
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Wang R, Zhong J, Pan X, Su Z, Xu Y, Zhang M, Chen X, Chen N, Yu T, Zhou Q. A novel intronic circular RNA circFGFR1 int2 up-regulates FGFR1 by recruiting transcriptional activators P65/FUS and suppressing miR-4687-5p to promote prostate cancer progression. J Transl Med 2023; 21:840. [PMID: 37993879 PMCID: PMC10664560 DOI: 10.1186/s12967-023-04718-y] [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: 08/25/2023] [Accepted: 11/10/2023] [Indexed: 11/24/2023] Open
Abstract
Fibroblast growth factor receptor 1 (FGFR1) is a core component of the FGFs/FGFR pathway that activates multiple signalling pathways, including ERK1/2, PI3K/AKT, PLCγ, and NF-κB. Aberrant expression of FGFR1 due to gene amplification, chromosome rearrangement, point mutation, and epigenetic deregulations, have been reported in various cancers. FGFR1 overexpression has also been reported in prostate cancer (PCa), but the underlining mechanisms are not clear. Here we report a novel circular RNA, circFGFR1int2, derived from intron 2 of FGFR1 gene, which is overexpressed in PCa and associated with tumor progression. Importantly, we show that circFGFR1int2 facilitates FGFR1 transcription by recruiting transcription activators P65/FUS and by interacting with FGFR1 promoter. Moreover, we show that circFGFR1int2 suppresses post-transcriptional inhibitory effects of miR-4687-5p on FGFR1 mRNA. These mechanisms synergistically promote PCa cell growth, migration, and invasion. Overexpression of circFGFR1int2 is significantly correlated with higher tumor grade, Gleason score, and PSA level, and is a significant unfavorable prognosticator for CRPC-free survival (CFS) (RR = 3.277, 95% confidence interval: 1.192-9.009; P = 0.021). These findings unravelled novel mechanisms controlling FGFR1 gene expression by intronic circRNA and its potential clinicopathological utility as a diagnostic or therapeutic target.
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Affiliation(s)
- Ruyue Wang
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Jinjing Zhong
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Xiuyi Pan
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Zhengzheng Su
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Yunyi Xu
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Mengni Zhang
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Xueqin Chen
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Ni Chen
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Ting Yu
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China.
| | - Qiao Zhou
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, 610041, China.
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11
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Yang S, Wijegunawardana D, Sheth U, Veire AM, Salgado JMS, Agrawal M, Zhou J, Pereira JD, Gendron TF, Guo JU. Aberrant splicing exonizes C9ORF72 repeat expansion in ALS/FTD. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.13.566896. [PMID: 38014069 PMCID: PMC10680656 DOI: 10.1101/2023.11.13.566896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
A nucleotide repeat expansion (NRE) in the first annotated intron of the C9ORF72 gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). While C9 NRE-containing RNAs can be translated into several toxic dipeptide repeat proteins, how an intronic NRE can assess the translation machinery in the cytoplasm remains unclear. By capturing and sequencing NRE-containing RNAs from patient-derived cells, we found that C9 NRE was exonized by the usage of downstream 5' splice sites and exported from the nucleus in a variety of spliced mRNA isoforms. C9ORF72 aberrant splicing was substantially elevated in both C9 NRE + motor neurons and human brain tissues. Furthermore, NREs above the pathological threshold were sufficient to activate cryptic splice sites in reporter mRNAs. In summary, our results revealed a crucial and potentially widespread role of repeat-induced aberrant splicing in the biogenesis, localization, and translation of NRE-containing RNAs.
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12
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Shi X, Liao S, Bi Z, Liu J, Li H, Feng C. Newly discovered circRNAs encoding proteins: recent progress. Front Genet 2023; 14:1264606. [PMID: 37829278 PMCID: PMC10565661 DOI: 10.3389/fgene.2023.1264606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 09/12/2023] [Indexed: 10/14/2023] Open
Abstract
Circular RNA (circRNA) is a special class of noncoding RNA molecules and the latest research hotspot in the field of RNA. CircRNA molecules have a closed loop structure, which is not affected by RNA exonuclease and has the characteristics of more stable expression. Previous studies have shown that circRNA molecules are rich in microRNA (miRNA) binding sites and act as miRNA sponges in cells. By interacting with miRNAs associated with tumors and other diseases, circRNAs play an important regulatory role. However, circRNAs have recently been found to have small open reading frames that enable them to encode peptides/proteins. These proteins have been reported to play an important role in the mechanism of regulation of a variety of diseases and have great potential in the diagnosis and treatment of diseases. In this review, we summarize the mechanism of action of the newly discovered circRNA-coding proteins since 2022 and briefly describe their research process. In addition, we also discuss the prediction model of the functional sites and encoded proteins of circRNAs, which provides a potential idea for future research on circRNAs.
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Affiliation(s)
- Xiaotong Shi
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital of Capital Medical University, Beijing, China
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Shiyu Liao
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Zhiguo Bi
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Jianguo Liu
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Hua Li
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital of Capital Medical University, Beijing, China
| | - Chunyang Feng
- Department of Obstetrics and Gynecology, Beijing Chao-yang Hospital of Capital Medical University, Beijing, China
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13
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Malik I, Tseng YJ, Wieland CM, Green KM, Zheng K, Calleja K, Todd PK. Dissecting the roles of EIF4G homologs reveals DAP5 as a modifier of CGG repeat-associated toxicity in a Drosophila model of FXTAS. Neurobiol Dis 2023; 184:106212. [PMID: 37352983 PMCID: PMC11149892 DOI: 10.1016/j.nbd.2023.106212] [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: 04/16/2023] [Revised: 06/19/2023] [Accepted: 06/21/2023] [Indexed: 06/25/2023] Open
Abstract
Neurodegeneration in Fragile X-associated tremor/ataxia syndrome (FXTAS) is caused by a CGG trinucleotide repeat expansion in the 5' UTR of FMR1. Expanded CGG repeat RNAs form stable secondary structures, which in turn support repeat-associated non-AUG (RAN) translation to produce toxic peptides. The parameters that impact RAN translation initiation efficiency are not well understood. Here we used a Drosophila melanogaster model of FXTAS to evaluate the role of the eIF4G family of eukaryotic translation initiation factors (EIF4G1, EIF4GII and EIF4G2/DAP5) in modulating RAN translation and CGG repeat-associated toxicity. DAP5 knockdown robustly suppressed CGG repeat-associated toxicity and inhibited RAN translation. Furthermore, knockdown of initiation factors that preferentially associate with DAP5 (such as EIF2β, EIF3F and EIF3G) also selectively suppressed CGG repeat-induced eye degeneration. In mammalian cellular reporter assays, DAP5 knockdown exhibited modest and cell-type specific effects on RAN translation. Taken together, these data support a role for DAP5 in CGG repeat associated toxicity possibly through modulation of RAN translation.
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Affiliation(s)
- Indranil Malik
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Yi-Ju Tseng
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA; Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Clare M Wieland
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Katelyn M Green
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Kristina Zheng
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Katyanne Calleja
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA; Ann Arbor Veterans Administration Healthcare, Ann Arbor, MI, USA.
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14
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Li Y, Dou X, Liu J, Xiao Y, Zhang Z, Hayes L, Wu R, Fu X, Ye Y, Yang B, Ostrow LW, He C, Sun S. Globally reduced N 6-methyladenosine (m 6A) in C9ORF72-ALS/FTD dysregulates RNA metabolism and contributes to neurodegeneration. Nat Neurosci 2023; 26:1328-1338. [PMID: 37365312 DOI: 10.1038/s41593-023-01374-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 05/31/2023] [Indexed: 06/28/2023]
Abstract
Repeat expansion in C9ORF72 is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Here we show that N6-methyladenosine (m6A), the most prevalent internal mRNA modification, is downregulated in C9ORF72-ALS/FTD patient-derived induced pluripotent stem cell (iPSC)-differentiated neurons and postmortem brain tissues. The global m6A hypomethylation leads to transcriptome-wide mRNA stabilization and upregulated gene expression, particularly for genes involved in synaptic activity and neuronal function. Moreover, the m6A modification in the C9ORF72 intron sequence upstream of the expanded repeats enhances RNA decay via the nuclear reader YTHDC1, and the antisense RNA repeats can also be regulated through m6A modification. The m6A reduction increases the accumulation of repeat RNAs and the encoded poly-dipeptides, contributing to disease pathogenesis. We further demonstrate that, by elevating m6A methylation, we could significantly reduce repeat RNA levels from both strands and the derived poly-dipeptides, rescue global mRNA homeostasis and improve survival of C9ORF72-ALS/FTD patient iPSC-derived neurons.
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Affiliation(s)
- Yini Li
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xiaoyang Dou
- Department of Chemistry and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
- Howard Hughes Medical Institute, Chicago, IL, USA
| | - Jun Liu
- Department of Chemistry and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
- Howard Hughes Medical Institute, Chicago, IL, USA
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Yu Xiao
- Department of Chemistry and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
- Howard Hughes Medical Institute, Chicago, IL, USA
| | - Zhe Zhang
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Lindsey Hayes
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Rong Wu
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xiujuan Fu
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yingzhi Ye
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Cellular and Molecular Physiology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Bing Yang
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, Bethesda, MD, USA
| | - Lyle W Ostrow
- Department of Neurology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Chuan He
- Department of Chemistry and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA.
- Howard Hughes Medical Institute, Chicago, IL, USA.
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA.
| | - Shuying Sun
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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15
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Livingston NM, Kwon J, Valera O, Saba JA, Sinha NK, Reddy P, Nelson B, Wolfe C, Ha T, Green R, Liu J, Wu B. Bursting translation on single mRNAs in live cells. Mol Cell 2023; 83:2276-2289.e11. [PMID: 37329884 PMCID: PMC10330622 DOI: 10.1016/j.molcel.2023.05.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 03/27/2023] [Accepted: 05/14/2023] [Indexed: 06/19/2023]
Abstract
Stochasticity has emerged as a mechanism of gene regulation. Much of this so-called "noise" has been attributed to bursting transcription. Although bursting transcription has been studied extensively, the role of stochasticity in translation has not been fully investigated due to the lack of enabling imaging technology. In this study, we developed techniques to track single mRNAs and their translation in live cells for hours, allowing the measurement of previously uncharacterized translation dynamics. We applied genetic and pharmacological perturbations to control translation kinetics and found that, like transcription, translation is not a constitutive process but instead cycles between inactive and active states, or "bursts." However, unlike transcription, which is largely frequency-modulated, complex structures in the 5'-untranslated region alter burst amplitudes. Bursting frequency can be controlled through cap-proximal sequences and trans-acting factors such as eIF4F. We coupled single-molecule imaging with stochastic modeling to quantitatively determine the kinetic parameters of translational bursting.
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Affiliation(s)
- Nathan M Livingston
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jiwoong Kwon
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Oliver Valera
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - James A Saba
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Niladri K Sinha
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Pranav Reddy
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Blake Nelson
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Clara Wolfe
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Taekjip Ha
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Rachel Green
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Jian Liu
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Bin Wu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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16
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Ghaffari LT, Trotti D, Haeusler AR. Differential response of C9orf72 transcripts following neuronal depolarization. iScience 2023; 26:106959. [PMID: 37332610 PMCID: PMC10272498 DOI: 10.1016/j.isci.2023.106959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 04/19/2023] [Accepted: 05/22/2023] [Indexed: 06/20/2023] Open
Abstract
The (G4C2)n nucleotide repeat expansion (NRE) mutation in C9orf72 is the most common genetic cause of ALS and FTD. The biological functions of C9orf72 are becoming understood, but it is unclear if this gene is regulated in a neural-specific manner. Neuronal activity is a crucial modifier of biological processes in health and neurodegenerative disease contexts. Here, we show that prolonged membrane depolarization in healthy human iPSC-cortical neurons leads to a significant downregulation of a transcript variant 3 (V3) of C9orf72, with a concomitant increase in variant 2 (V2), which leads to total C9orf72 RNA transcript levels remaining unchanged. However, the same response is not observed in cortical neurons derived from patients with the C9-NRE mutation. These findings reveal the impact of depolarization on C9orf72 transcripts, and how this response diverges in C9-NRE-carriers, which may have important implications in the underlying unique clinical associations of C9-NRE transcripts and disease pathogenesis.
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Affiliation(s)
- Layla T. Ghaffari
- Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Davide Trotti
- Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Aaron R. Haeusler
- Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
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17
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Li J, Song Y, Cai H, Zhou B, Ma J. Roles of circRNA dysregulation in esophageal squamous cell carcinoma tumor microenvironment. Front Oncol 2023; 13:1153207. [PMID: 37384299 PMCID: PMC10299836 DOI: 10.3389/fonc.2023.1153207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 05/30/2023] [Indexed: 06/30/2023] Open
Abstract
Esophageal squamous cell carcinoma (ESCC) is the most prevalent histological esophageal cancer characterized by advanced diagnosis, metastasis, resistance to treatment, and frequent recurrence. In recent years, numerous human disorders such as ESCC, have been linked to abnormal expression of circular RNAs (circRNAs), suggesting that they are fundamental to the intricate system of gene regulation that governs ESCC formation. The tumor microenvironment (TME), referring to the area surrounding the tumor cells, is composed of multiple components, including stromal cells, immune cells, the vascular system, extracellular matrix (ECM), and numerous signaling molecules. In this review, we briefly described the biological purposes and mechanisms of aberrant circRNA expression in the TME of ESCC, including the immune microenvironment, angiogenesis, epithelial-to-mesenchymal transition, hypoxia, metabolism, and radiotherapy resistance. As in-depth research into the processes of circRNAs in the TME of ESCC continues, circRNAs are promising therapeutic targets or delivery systems for cancer therapy and diagnostic and prognostic indicators for ESCC.
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Affiliation(s)
- Jingyi Li
- Department of Clinical Laboratory, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Yuxia Song
- Department of Reproductive Medicine, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Huihong Cai
- Department of Clinical Laboratory, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Bo Zhou
- Medical Research Center, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Jun Ma
- Department of Clinical Laboratory, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
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18
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Zhang Y, Luo J, Yang W, Ye WC. CircRNAs in colorectal cancer: potential biomarkers and therapeutic targets. Cell Death Dis 2023; 14:353. [PMID: 37296107 PMCID: PMC10250185 DOI: 10.1038/s41419-023-05881-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 05/09/2023] [Accepted: 05/31/2023] [Indexed: 06/12/2023]
Abstract
Globally, colorectal cancer (CRC) is the third most prevalent cancer and the second leading cause of cancer-related deaths. Circular RNAs (circRNAs) are single-stranded RNA with covalently closed-loop structures and are highly stable, conserved, and abundantly expressed in various organs and tissues. Recent research found abnormal circRNA expression in CRC patients' blood/serum, cells, CRC tissues, and exosomes. Furthermore, mounting data demonstrated that circRNAs are crucial to the development of CRC. CircRNAs have been shown to exert biological functions by acting as microRNA sponges, RNA-binding protein sponges, regulators of gene splicing and transcription, and protein/peptide translators. These characteristics make circRNAs potential markers for CRC diagnosis and prognosis, potential therapeutic targets, and circRNA-based therapies. However, further studies are still necessary to improve the understanding of the roles and biological mechanisms of circRNAs in the development of CRC. In this review, up-to-date research on the role of circRNAs in CRC was examined, focusing on their potential application in CRC diagnosis and targeted therapy, which would advance the knowledge of the functions of circRNAs in the development and progression of CRC.
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Affiliation(s)
- Yuying Zhang
- Central Laboratory, Shenzhen Longhua Maternity and Child Healthcare Hospital, Shenzhen, 518109, China
| | - Jingyan Luo
- Forevergen Biosciences Centre, Guangzhou International Biotech Island, Guangzhou, 510300, China
| | - Weikang Yang
- Department of Prevention and Healthcare, Shenzhen Longhua Maternity and Child Healthcare Hospital, Shenzhen, 518109, China
| | - Wen-Chu Ye
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China.
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19
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Hosaka T, Tsuji H, Kwak S. Roles of Aging, Circular RNAs, and RNA Editing in the Pathogenesis of Amyotrophic Lateral Sclerosis: Potential Biomarkers and Therapeutic Targets. Cells 2023; 12:1443. [PMID: 37408276 DOI: 10.3390/cells12101443] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 07/07/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an incurable motor neuron disease caused by upper and lower motor neuron death. Despite advances in our understanding of ALS pathogenesis, effective treatment for this fatal disease remains elusive. As aging is a major risk factor for ALS, age-related molecular changes may provide clues for the development of new therapeutic strategies. Dysregulation of age-dependent RNA metabolism plays a pivotal role in the pathogenesis of ALS. In addition, failure of RNA editing at the glutamine/arginine (Q/R) site of GluA2 mRNA causes excitotoxicity due to excessive Ca2+ influx through Ca2+-permeable α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors, which is recognized as an underlying mechanism of motor neuron death in ALS. Circular RNAs (circRNAs), a circular form of cognate RNA generated by back-splicing, are abundant in the brain and accumulate with age. Hence, they are assumed to play a role in neurodegeneration. Emerging evidence has demonstrated that age-related dysregulation of RNA editing and changes in circRNA expression are involved in ALS pathogenesis. Herein, we review the potential associations between age-dependent changes in circRNAs and RNA editing, and discuss the possibility of developing new therapies and biomarkers for ALS based on age-related changes in circRNAs and dysregulation of RNA editing.
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Affiliation(s)
- Takashi Hosaka
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan
- University of Tsukuba Hospital/Jichi Medical University Joint Ibaraki Western Regional Clinical Education Center, Chikusei 308-0813, Japan
- Department of Internal Medicine, Ibaraki Western Medical Center, Chikusei 308-0813, Japan
| | - Hiroshi Tsuji
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan
| | - Shin Kwak
- Department of Neurology, Tokyo Medical University, Tokyo 160-0023, Japan
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20
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Blake LA, Liu Y, Inoue T, Wu B. A Rapid Inducible RNA Decay system reveals fast mRNA decay in P-bodies. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.26.538452. [PMID: 37162943 PMCID: PMC10168379 DOI: 10.1101/2023.04.26.538452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
RNA decay plays a crucial role in regulating mRNA abundance and gene expression. Modulation of RNA degradation is imperative to investigate an RNA's function. However, information regarding where and how RNA decay occurs remains scarce, partially because existing technologies fail to initiate RNA decay with the spatiotemporal precision or transcript specificity required to capture this stochastic and transient process. Here, we devised a general method that employs inducible tethering of regulatory protein factors to target RNAs and modulate their metabolism. Specifically, we established a Rapid Inducible Decay of RNA (RIDR) technology to degrade target mRNA within minutes. The fast and synchronous induction enabled direct visualization of mRNA decay dynamics in cells with spatiotemporal precision previously unattainable. When applying RIDR to endogenous ACTB mRNA, we observed rapid formation and disappearance of RNA granules, which coincided with pre-existing processing bodies (P-bodies). We measured the time-resolved RNA distribution in P-bodies and cytoplasm after induction, and compared different models of P-body function. We determined that mRNAs rapidly decayed in P-bodies upon induction. Additionally, we validated the functional role of P-bodies by knocking down specific a P-body constituent protein and RNA degradation enzyme. This study determined compartmentalized RNA decay kinetics for the first time. Together, RIDR provides a valuable and generalizable tool to study the spatial and temporal RNA metabolism in cells.
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21
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Van't Spijker HM, Almeida S. How villains are made: The translation of dipeptide repeat proteins in C9ORF72-ALS/FTD. Gene 2023; 858:147167. [PMID: 36621656 PMCID: PMC9928902 DOI: 10.1016/j.gene.2023.147167] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023]
Abstract
A hexanucleotide repeat expansion in the C9ORF72 gene is the most common genetic alteration associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). These neurodegenerative diseases share genetic, clinical and pathological features. The mutation in C9ORF72 appears to drive pathogenesis through a combination of loss of C9ORF72 normal function and gain of toxic effects due to the repeat expansion, which result in aggregation prone expanded RNAs and dipeptide repeat (DPR) proteins. Studies in cellular and animal models indicate that the DPR proteins are the more toxic species. Thus, a large body of research has focused on identifying the cellular pathways most directly impacted by these toxic proteins, with the goal of characterizing disease pathogenesis and nominating potential targets for therapeutic development. The preventative block of the production of the toxic proteins before they can cause harm is a second strategy of intense focus. Despite the considerable amount of effort dedicated to this prophylactic approach, it is still unclear how the DPR proteins are synthesized from RNAs harboring repeat expansions. In this review, we summarize our current knowledge of the specific protein translation mechanisms shown to account for the synthesis of DPR proteins. We will then discuss how enhanced understanding of the composition of these toxic effectors could help in refining disease mechanisms, and paving the way to identify and design effective prophylactic therapies for C9ORF72 ALS-FTD.
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Affiliation(s)
- Heleen M Van't Spijker
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Sandra Almeida
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
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22
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McMillan M, Gomez N, Hsieh C, Bekier M, Li X, Miguez R, Tank EMH, Barmada SJ. RNA methylation influences TDP43 binding and disease pathogenesis in models of amyotrophic lateral sclerosis and frontotemporal dementia. Mol Cell 2023; 83:219-236.e7. [PMID: 36634675 PMCID: PMC9899051 DOI: 10.1016/j.molcel.2022.12.019] [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: 04/04/2022] [Revised: 11/14/2022] [Accepted: 12/16/2022] [Indexed: 01/13/2023]
Abstract
RNA methylation at adenosine N6 (m6A) is one of the most common RNA modifications, impacting RNA stability, transport, and translation. Previous studies uncovered RNA destabilization in amyotrophic lateral sclerosis (ALS) models in association with accumulation of the RNA-binding protein TDP43. Here, we show that TDP43 recognizes m6A RNA and that RNA methylation is critical for both TDP43 binding and autoregulation. We also observed extensive RNA hypermethylation in ALS spinal cord, corresponding to methylated TDP43 substrates. Emphasizing the importance of m6A for TDP43 binding and function, we identified several m6A factors that enhance or suppress TDP43-mediated toxicity via single-cell CRISPR-Cas9 in primary neurons. The most promising modifier-the canonical m6A reader YTHDF2-accumulated within ALS spinal neurons, and its knockdown prolonged the survival of human neurons carrying ALS-associated mutations. Collectively, these data show that m6A modifications modulate RNA binding by TDP43 and that m6A is pivotal for TDP43-related neurodegeneration in ALS.
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Affiliation(s)
- Michael McMillan
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA; Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nicolas Gomez
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA; Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI 48109, USA; Medical Scientist Training Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Caroline Hsieh
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA; Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael Bekier
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Xingli Li
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Roberto Miguez
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Elizabeth M H Tank
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sami J Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA; Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI 48109, USA.
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23
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Repeat-associated non-AUG translation induces cytoplasmic aggregation of CAG repeat-containing RNAs. Proc Natl Acad Sci U S A 2023; 120:e2215071120. [PMID: 36623192 PMCID: PMC9934169 DOI: 10.1073/pnas.2215071120] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
CAG trinucleotide repeat expansions cause several neurodegenerative diseases, including Huntington's disease and spinocerebellar ataxia. RNAs with expanded CAG repeats contribute to disease in two unusual ways. First, these repeat-containing RNAs may agglomerate in the nucleus as foci that sequester several RNA-binding proteins. Second, these RNAs may undergo aberrant repeat-associated non-AUG (RAN) translation in multiple frames and produce aggregation-prone proteins. The relationship between RAN translation and RNA foci, and their relative contributions to cellular dysfunction, are unclear. Here, we show that CAG repeat-containing RNAs that undergo RAN translation first accumulate at nuclear foci and, over time, are exported to the cytoplasm. In the cytoplasm, these RNAs are initially dispersed but, upon RAN translation, aggregate with the RAN translation products. These RNA-RAN protein agglomerates sequester various RNA-binding proteins and are associated with the disruption of nucleocytoplasmic transport and cell death. In contrast, RNA accumulation at nuclear foci alone does not produce discernable defects in nucleocytoplasmic transport or cell viability. Inhibition of RAN translation prevents cytoplasmic RNA aggregation and alleviates cell toxicity. Our findings demonstrate that RAN translation-induced RNA-protein aggregation correlates with the key pathological hallmarks observed in disease and suggest that cytoplasmic RNA aggregation may be an underappreciated phenomenon in CAG trinucleotide repeat expansion disorders.
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24
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Liu C, Wu X, Gokulnath P, Li G, Xiao J. The Functions and Mechanisms of Translatable Circular RNAs. J Pharmacol Exp Ther 2023; 384:52-60. [PMID: 35609922 DOI: 10.1124/jpet.122.001085] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 04/03/2022] [Accepted: 04/29/2022] [Indexed: 12/27/2022] Open
Abstract
Circular RNAs (circRNAs) are covalently closed RNA produced by back-splicing. CircRNAs have been considered as a type of noncoding RNAs for a long time. However, recent studies have shown that circRNAs can be translated into functional proteins. Proteins specifically encoded by circRNAs have been proved to play important roles in cancer pathology. In this review, we introduce the methods commonly used to identify and validate circRNA translation in detail. We also describe the major mechanisms driving the translation of these circRNAs. In addition, we summarize the main functions of the circRNA-encoded proteins in both physiologic and pathologic conditions. Finally, we discuss the therapeutic potential and challenges in the usage of synthetic translatable circRNAs. This brief review highlights recent discoveries made in this field and the progress of therapy based on translatable circRNAs. SIGNIFICANCE STATEMENT: Understanding the translation of circRNA could facilitate the identification of novel drug targets in various diseases. Moreover, some circRNA encoded proteins were demonstrated to have therapeutic functions in cancer. The application of synthetic circRNAs as carriers to achieve stable protein expression in vitro and in vivo has tremendous therapeutic potential.
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Affiliation(s)
- Chang Liu
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
| | - Xinying Wu
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
| | - Priyanka Gokulnath
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
| | - Guoping Li
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
| | - Junjie Xiao
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China (C.L., X.W., J.X.); Cardiac Regeneration and Ageing Laboratory, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai, China (C.L., X.W., J.X.); and Cardiovascular Division of the Massachusetts General Hospitaland Harvard Medical School, Boston, Massachusetts (P.G., G.L.)
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25
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Huang Y, Li Y, Lin W, Fan S, Chen H, Xia J, Pi J, Xu JF. Promising Roles of Circular RNAs as Biomarkers and Targets for Potential Diagnosis and Therapy of Tuberculosis. Biomolecules 2022; 12:biom12091235. [PMID: 36139074 PMCID: PMC9496049 DOI: 10.3390/biom12091235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 12/02/2022] Open
Abstract
Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb) infection, remains one of the most threatening infectious diseases worldwide. A series of challenges still exist for TB prevention, diagnosis and treatment, which therefore require more attempts to clarify the pathological and immunological mechanisms in the development and progression of TB. Circular RNAs (circRNAs) are a large class of non-coding RNA, mostly expressed in eukaryotic cells, which are generated by the spliceosome through the back-splicing of linear RNAs. Accumulating studies have identified that circRNAs are widely involved in a variety of physiological and pathological processes, acting as the sponges or decoys for microRNAs and proteins, scaffold platforms for proteins, modulators for transcription and special templates for translation. Due to the stable and widely spread characteristics of circRNAs, they are expected to serve as promising prognostic/diagnostic biomarkers and therapeutic targets for diseases. In this review, we briefly describe the biogenesis, classification, detection technology and functions of circRNAs, and, in particular, outline the dynamic, and sometimes aberrant changes of circRNAs in TB. Moreover, we further summarize the recent progress of research linking circRNAs to TB-related pathogenetic processes, as well as the potential roles of circRNAs as diagnostic biomarkers and miRNAs sponges in the case of Mtb infection, which is expected to enhance our understanding of TB and provide some novel ideas about how to overcome the challenges associated TB in the future.
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Affiliation(s)
- Yifan Huang
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan 523808, China
- Institute of Laboratory Medicine, School of Medical Technology, Guangdong Medical University, Dongguan 523808, China
| | - Ying Li
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan 523808, China
- Institute of Laboratory Medicine, School of Medical Technology, Guangdong Medical University, Dongguan 523808, China
| | - Wensen Lin
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan 523808, China
- Institute of Laboratory Medicine, School of Medical Technology, Guangdong Medical University, Dongguan 523808, China
| | - Shuhao Fan
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan 523808, China
- Institute of Laboratory Medicine, School of Medical Technology, Guangdong Medical University, Dongguan 523808, China
| | - Haorong Chen
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan 523808, China
- Institute of Laboratory Medicine, School of Medical Technology, Guangdong Medical University, Dongguan 523808, China
| | - Jiaojiao Xia
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan 523808, China
- Institute of Laboratory Medicine, School of Medical Technology, Guangdong Medical University, Dongguan 523808, China
| | - Jiang Pi
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan 523808, China
- Institute of Laboratory Medicine, School of Medical Technology, Guangdong Medical University, Dongguan 523808, China
- Correspondence: (J.P.); (J.-F.X.)
| | - Jun-Fa Xu
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan 523808, China
- Institute of Laboratory Medicine, School of Medical Technology, Guangdong Medical University, Dongguan 523808, China
- Correspondence: (J.P.); (J.-F.X.)
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26
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Green KM, Miller SL, Malik I, Todd PK. Non-canonical initiation factors modulate repeat-associated non-AUG translation. Hum Mol Genet 2022; 31:2521-2534. [PMID: 35220421 PMCID: PMC9618161 DOI: 10.1093/hmg/ddac021] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 12/28/2021] [Accepted: 01/14/2022] [Indexed: 11/14/2022] Open
Abstract
Repeat-associated non-AUG (RAN) translation of expanded repeat-mutation mRNA produces toxic peptides in neurons of patients suffering from neurodegenerative diseases. Recent findings indicate that RAN translation in diverse model systems is not inhibited by cellular stressors that impair global translation through phosphorylation of the alpha subunit of eIF2, the essential eukaryotic translation initiation factor that brings the initiator tRNA to the 40S ribosome. Using in vitro, cell-based and Drosophila models, we examined the role of alternative ternary complex factors that may function in place of eIF2, including eIF2A, eIF2D, DENR and MCTS1. Among these factors, DENR knockdown had the greatest inhibitory effect on RAN translation of expanded GGGGCC and CGG repeat reporters and its reduction improved the survival of Drosophila expressing expanded GGGGCC repeats. Taken together, these data support a role for alternative initiation factors in RAN translation and suggest these may serve as novel therapeutic targets in neurodegenerative disease.
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Affiliation(s)
- Katelyn M Green
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Shannon L Miller
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Indranil Malik
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI, USA
- VA Ann Arbor Healthcare System, Ann Arbor, MI, USA
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27
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Baud A, Derbis M, Tutak K, Sobczak K. Partners in crime: Proteins implicated in
RNA
repeat expansion diseases. WIRES RNA 2022; 13:e1709. [PMID: 35229468 PMCID: PMC9539487 DOI: 10.1002/wrna.1709] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 11/06/2022]
Affiliation(s)
- Anna Baud
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Magdalena Derbis
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Katarzyna Tutak
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Krzysztof Sobczak
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
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28
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Loveland AB, Svidritskiy E, Susorov D, Lee S, Park A, Zvornicanin S, Demo G, Gao FB, Korostelev AA. Ribosome inhibition by C9ORF72-ALS/FTD-associated poly-PR and poly-GR proteins revealed by cryo-EM. Nat Commun 2022; 13:2776. [PMID: 35589706 PMCID: PMC9120013 DOI: 10.1038/s41467-022-30418-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 04/29/2022] [Indexed: 12/15/2022] Open
Abstract
Toxic dipeptide-repeat (DPR) proteins are produced from expanded G4C2 repeats in the C9ORF72 gene, the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Two DPR proteins, poly-PR and poly-GR, repress cellular translation but the molecular mechanism remains unknown. Here we show that poly-PR and poly-GR of ≥20 repeats inhibit the ribosome's peptidyl-transferase activity at nanomolar concentrations, comparable to specific translation inhibitors. High-resolution cryogenic electron microscopy (cryo-EM) reveals that poly-PR and poly-GR block the polypeptide tunnel of the ribosome, extending into the peptidyl-transferase center (PTC). Consistent with these findings, the macrolide erythromycin, which binds in the tunnel, competes with poly-PR and restores peptidyl-transferase activity. Our results demonstrate that strong and specific binding of poly-PR and poly-GR in the ribosomal tunnel blocks translation, revealing the structural basis of their toxicity in C9ORF72-ALS/FTD.
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Affiliation(s)
- Anna B Loveland
- RNA Therapeutics Institute, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
| | - Egor Svidritskiy
- RNA Therapeutics Institute, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
| | - Denis Susorov
- RNA Therapeutics Institute, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
| | - Soojin Lee
- Department of Neurology, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
| | - Alexander Park
- RNA Therapeutics Institute, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
| | - Sarah Zvornicanin
- RNA Therapeutics Institute, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
| | - Gabriel Demo
- RNA Therapeutics Institute, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Fen-Biao Gao
- Department of Neurology, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA.
| | - Andrei A Korostelev
- RNA Therapeutics Institute, UMass Chan Medical School, 368 Plantation Street, Worcester, MA, 01605, USA.
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29
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Robic A, Cerutti C, Demars J, Kühn C. From the comparative study of a circRNA originating from an mammalian ATXN2L intron to understanding the genesis of intron lariat-derived circRNAs. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2022; 1865:194815. [PMID: 35513260 DOI: 10.1016/j.bbagrm.2022.194815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 04/12/2022] [Accepted: 04/14/2022] [Indexed: 06/14/2023]
Abstract
Circular intronic RNAs (ciRNAs) are still unexplored regarding mechanisms for their emergence. We considered the ATXN2L intron lariat-derived circular RNA (ciRNA-ATXN2L) as an opportunity to conduct a cross-species examination of ciRNA genesis. To this end, we investigated 207 datasets from 4 tissues and from 13 mammalian species. While in eight species, ciRNA-ATXN2L was never detected, in pigs and rabbits, ciRNA-ATXN2L was expressed in all tissues and sometimes at very high levels. Bovine tissues were an intermediate case and in macaques and cats, only ciRNA-ATXN2L traces were detected. The pattern of ciRNA-ATXN2L restricted to only five species is not related to a particular evolution of intronic sequences. To empower our analysis, we considered 221 additional introns including 80 introns where a lariat-derived ciRNA was previously described. The primary driver of micro-ciRNA genesis (< 155 nt as ciRNA-ATXN2L) appears to be the absence of a canonical "A" (i.e. a "tnA" located in the usual branching region) to build the lariat around this adenosine. The balance between available "non canonical-A" (no ciRNA genesis) and "non-A" (ciRNA genesis) for use as a branch point to build the lariat could modify the expression level of ciRNA-ATXN2L. In addition, the rare localization of the 2'-5' bond in an open RNA secondary structure could also negatively affect the lifetime of ciRNAs (macaque ciRNA-ATXN2L). Our analyses suggest that ciRNA-ATXN2L is likely a functionless splice remnant. This study provides a better understanding of the ciRNAs origin, especially drivers for micro ciRNA genesis.
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Affiliation(s)
- Annie Robic
- GenPhySE, Université de Toulouse, INRAE, ENVT, 31326 Castanet Tolosan, France.
| | - Chloé Cerutti
- GenPhySE, Université de Toulouse, INRAE, ENVT, 31326 Castanet Tolosan, France.
| | - Julie Demars
- GenPhySE, Université de Toulouse, INRAE, ENVT, 31326 Castanet Tolosan, France.
| | - Christa Kühn
- Institute of Genome Biology, Research Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany; Faculty of Agricultural and Environmental Sciences, University of Rostock, 18059 Rostock, Germany.
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30
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D’Anca M, Buccellato FR, Fenoglio C, Galimberti D. Circular RNAs: Emblematic Players of Neurogenesis and Neurodegeneration. Int J Mol Sci 2022; 23:ijms23084134. [PMID: 35456950 PMCID: PMC9032451 DOI: 10.3390/ijms23084134] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 04/06/2022] [Indexed: 12/13/2022] Open
Abstract
In the fascinating landscape of non-coding RNAs (ncRNAs), circular RNAs (circRNAs) are peeping out as a new promising and appreciated class of molecules with great potential as diagnostic and prognostic biomarkers. They come from circularization of single-stranded RNA molecules covalently closed and generated through alternative mRNA splicing. Dismissed for many years, similar to aberrant splicing by-products, nowadays, their role has been regained. They are able to regulate the expression of linear mRNA transcripts at different levels acting as miRNA sponges, interacting with ribonucleoproteins or exerting a control on gene expression. On the other hand, being extremely conserved across phyla and stable, cell and tissue specific, mostly abundant than the linear RNAs, it is not surprising that they should have critical biological functions. Curiously, circRNAs are particularly expressed in brain and they build up during aging and age-related diseases. These extraordinary peculiarities make circRNAs potentially suitable as promising molecular biomarkers, especially of aging and neurodegenerative diseases. This review aims to explore new evidence on circRNAs, emphasizing their role in aging and pathogenesis of major neurodegenerative disorders, Alzheimer's disease, frontotemporal dementia, and Parkinson's diseases with a look toward their potential usefulness in biomarker searching.
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Affiliation(s)
- Marianna D’Anca
- Foundation IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy; (F.R.B.); or (C.F.); or (D.G.)
- Correspondence:
| | - Francesca R. Buccellato
- Foundation IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy; (F.R.B.); or (C.F.); or (D.G.)
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy
| | - Chiara Fenoglio
- Foundation IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy; (F.R.B.); or (C.F.); or (D.G.)
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy
| | - Daniela Galimberti
- Foundation IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy; (F.R.B.); or (C.F.); or (D.G.)
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy
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31
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Misir S, Wu N, Yang BB. Specific expression and functions of circular RNAs. Cell Death Differ 2022; 29:481-491. [PMID: 35169296 PMCID: PMC8901656 DOI: 10.1038/s41418-022-00948-7] [Citation(s) in RCA: 133] [Impact Index Per Article: 66.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 02/07/2023] Open
Abstract
In recent years, circular RNAs (circRNAs), a new class of RNA molecules characterized by their covalently closed circular structure, have become a new research paradigm in RNA biology. Many circRNAs are conserved among eukaryotes, localize in specific subcellular compartments, and play different biological roles. Accumulating evidence shows that circRNAs regulate a diversity of cellular processes by acting as miRNA sponges, anchors for circRNA binding proteins (cRBPs), transcriptional regulators, molecular scaffolds, and sources for translation of small proteins/peptides. The emergence of the biological functions of circRNAs has brought a new perspective to our understanding of cellular physiology and disease pathogenesis. Recent studies have shown that the expression of circRNAs is tissue- and cell type-specific and specifically regulated through development or disease progression, where they exert specific biological functions. However, the mechanisms underlying these remain largely unknown. A deeper understanding of how the specific expression of circRNAs is regulated to exert specific biological functions will enable the use of circRNA as a biomarker in clinical practice and the development of new therapeutic approaches. This review aims to summarize recent developments in circRNA biogenesis, functions, and molecular mechanisms. We also provide some specific circRNAs as examples to show their tissue-specific distribution and evaluate the possibility of applying circRNA technologies in molecular research and therapeutics.
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Affiliation(s)
- Sema Misir
- grid.17063.330000 0001 2157 2938Sunnybrook Research Institute, and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Nan Wu
- grid.17063.330000 0001 2157 2938Sunnybrook Research Institute, and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Burton B. Yang
- grid.17063.330000 0001 2157 2938Sunnybrook Research Institute, and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
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Chen X, Zhou M, Yant L, Huang C. Circular RNA in disease: Basic properties and biomedical relevance. WILEY INTERDISCIPLINARY REVIEWS. RNA 2022; 13:e1723. [PMID: 35194939 DOI: 10.1002/wrna.1723] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 12/15/2021] [Accepted: 01/31/2022] [Indexed: 12/26/2022]
Abstract
Circular RNAs (circRNAs) represent a class of covalently closed RNA molecules with great diversity in molecular features, functions, and regulatory mechanisms. Emerging advances in our understanding of circRNA biogenesis, nuclear export, and stability control have been made very recently. In particular, novel roles of circRNAs in diverse human diseases are increasingly recognized. Various circRNAs have been found to affect many disease-relevant pathways through a diverse array of mechanisms, including forming R-loops, sponging miRNAs or proteins, and translating functional proteins, resulting in different pathological phenotypes. This recent progress calls for a revised view of circRNAs in diseases threatening the lives and health of humans. In this review, we focus on the recently described functional relevance of disease-associated circRNAs as well as the potential of circRNAs in diverse clinical applications. This article is categorized under: RNA in Disease and Development > RNA in Disease Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs.
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Affiliation(s)
- Xiaolan Chen
- School of Life Sciences, Chongqing University, Chongqing, China.,Center of Plant Functional Genomics, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, China
| | - Min Zhou
- School of Life Sciences, Chongqing University, Chongqing, China.,Center of Plant Functional Genomics, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, China
| | - Levi Yant
- Future Food Beacon of Excellence and School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Chuan Huang
- School of Life Sciences, Chongqing University, Chongqing, China.,Center of Plant Functional Genomics, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, China
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Ha T, Kaiser C, Myong S, Wu B, Xiao J. Next generation single-molecule techniques: Imaging, labeling, and manipulation in vitro and in cellulo. Mol Cell 2022; 82:304-314. [PMID: 35063098 DOI: 10.1016/j.molcel.2021.12.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 12/14/2021] [Accepted: 12/14/2021] [Indexed: 12/24/2022]
Abstract
Owing to their unique abilities to manipulate, label, and image individual molecules in vitro and in cellulo, single-molecule techniques provide previously unattainable access to elementary biological processes. In imaging, single-molecule fluorescence resonance energy transfer (smFRET) and protein-induced fluorescence enhancement in vitro can report on conformational changes and molecular interactions, single-molecule pull-down (SiMPull) can capture and analyze the composition and function of native protein complexes, and single-molecule tracking (SMT) in live cells reveals cellular structures and dynamics. In labeling, the abilities to specifically label genomic loci, mRNA, and nascent polypeptides in cells have uncovered chromosome organization and dynamics, transcription and translation dynamics, and gene expression regulation. In manipulation, optical tweezers, integration of single-molecule fluorescence with force measurements, and single-molecule force probes in live cells have transformed our mechanistic understanding of diverse biological processes, ranging from protein folding, nucleic acids-protein interactions to cell surface receptor function.
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Affiliation(s)
- Taekjip Ha
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA; Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; Howard Hughes Medical Institute, Baltimore, MD 21205, USA.
| | - Christian Kaiser
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Sua Myong
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Bin Wu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Jie Xiao
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
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Louis C, Coulouarn C. One stone, two birds: circACTN4, a nexus for a coordinated activation of Hippo and Wnt/β-catenin pathways in cholangiocarcinoma. J Hepatol 2022; 76:8-10. [PMID: 34653593 DOI: 10.1016/j.jhep.2021.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 09/29/2021] [Accepted: 10/01/2021] [Indexed: 12/12/2022]
Affiliation(s)
- Corentin Louis
- Inserm, Univ Rennes 1, UMR_S 1242, COSS (Chemistry, Oncogenesis Stress Signaling), Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
| | - Cédric Coulouarn
- Inserm, Univ Rennes 1, UMR_S 1242, COSS (Chemistry, Oncogenesis Stress Signaling), Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France.
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Guo X, Piao H. Research Progress of circRNAs in Glioblastoma. Front Cell Dev Biol 2021; 9:791892. [PMID: 34881248 PMCID: PMC8645988 DOI: 10.3389/fcell.2021.791892] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 11/02/2021] [Indexed: 01/10/2023] Open
Abstract
Circular RNAs (circRNAs) are a class of single-stranded covalently closed non-coding RNAs without a 5' cap structure or 3' terminal poly (A) tail, which are expressed in a variety of tissues and cells with conserved, stable and specific characteristics. Glioblastoma (GBM) is the most aggressive and lethal tumor in the central nervous system, characterized by high recurrence and mortality rates. The specific expression of circRNAs in GBM has demonstrated their potential to become new biomarkers for the development of GBM. The specific expression of circRNAs in GBM has shown their potential as new biomarkers for GBM cell proliferation, apoptosis, migration and invasion, which provides new ideas for GBM treatment. In this paper, we will review the biological properties and functions of circRNAs and their biological roles and clinical applications in GBM.
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Affiliation(s)
- Xu Guo
- Department of Neurosurgery, Liaoning Cancer Hospital and Institute, Cancer Hospital of China Medical University, Shenyang, China
| | - Haozhe Piao
- Department of Neurosurgery, Liaoning Cancer Hospital and Institute, Cancer Hospital of China Medical University, Shenyang, China
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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.
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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.
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Sun YY, Wang L, Liu JM, Yuan P. Reply to: circGSAP: A New Clinical Biomarker for Idiopathic Pulmonary Hypertension? Am J Respir Crit Care Med 2021; 205:254. [PMID: 34739352 PMCID: PMC8787256 DOI: 10.1164/rccm.202108-1905le] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Yuan-Yuan Sun
- Tongji University Affiliated Shanghai Pulmonary Hospital, 89668, Department of Cardio-Pulmonary Circulation, Shanghai, China
| | - Lan Wang
- Shanghai Pulmonary Hospital, Tongji University School of Medicine, Department of Cardio-Pulmonary Circulation, Shanghai, China
| | - Jin-Ming Liu
- Tongji University Affiliated Shanghai Pulmonary Hospital, 89668, Pulmonary Circulation, Shanghai, China
| | - Ping Yuan
- Tongji University Affiliated Shanghai Pulmonary Hospital, 89668, Shanghai, China;
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Laneve P, Tollis P, Caffarelli E. RNA Deregulation in Amyotrophic Lateral Sclerosis: The Noncoding Perspective. Int J Mol Sci 2021; 22:10285. [PMID: 34638636 PMCID: PMC8508793 DOI: 10.3390/ijms221910285] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/17/2021] [Accepted: 09/22/2021] [Indexed: 12/18/2022] Open
Abstract
RNA metabolism is central to cellular physiopathology. Almost all the molecular pathways underpinning biological processes are affected by the events governing the RNA life cycle, ranging from transcription to degradation. The deregulation of these processes contributes to the onset and progression of human diseases. In recent decades, considerable efforts have been devoted to the characterization of noncoding RNAs (ncRNAs) and to the study of their role in the homeostasis of the nervous system (NS), where they are highly enriched. Acting as major regulators of gene expression, ncRNAs orchestrate all the steps of the differentiation programs, participate in the mechanisms underlying neural functions, and are crucially implicated in the development of neuronal pathologies, among which are neurodegenerative diseases. This review aims to explore the link between ncRNA dysregulation and amyotrophic lateral sclerosis (ALS), the most frequent motoneuron (MN) disorder in adults. Notably, defective RNA metabolism is known to be largely associated with this pathology, which is often regarded as an RNA disease. We also discuss the potential role that these transcripts may play as diagnostic biomarkers and therapeutic targets.
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Affiliation(s)
- Pietro Laneve
- Institute of Molecular Biology and Pathology, National Research Council, 00185 Rome, Italy
| | - Paolo Tollis
- Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, 00185 Rome, Italy;
| | - Elisa Caffarelli
- Institute of Molecular Biology and Pathology, National Research Council, 00185 Rome, Italy
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Nuclear export and translation of circular repeat-containing intronic RNA in C9ORF72-ALS/FTD. Nat Commun 2021; 12:4908. [PMID: 34389711 PMCID: PMC8363653 DOI: 10.1038/s41467-021-25082-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Accepted: 07/16/2021] [Indexed: 12/14/2022] Open
Abstract
C9ORF72 hexanucleotide GGGGCC repeat expansion is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Repeat-containing RNA mediates toxicity through nuclear granules and dipeptide repeat (DPR) proteins produced by repeat-associated non-AUG translation. However, it remains unclear how the intron-localized repeats are exported and translated in the cytoplasm. We use single molecule imaging approach to examine the molecular identity and spatiotemporal dynamics of the repeat RNA. We demonstrate that the spliced intron with G-rich repeats is stabilized in a circular form due to defective lariat debranching. The spliced circular intron, instead of pre-mRNA, serves as the translation template. The NXF1-NXT1 pathway plays an important role in the nuclear export of the circular intron and modulates toxic DPR production. This study reveals an uncharacterized disease-causing RNA species mediated by repeat expansion and demonstrates the importance of RNA spatial localization to understand disease etiology. Hexanucleotide repeat expansion in the intron 1 of the C9ORF72 gene can cause amyotrophic lateral sclerosis (ALS) and frontal temporal dementia (FTD). Here the authors use single molecule imaging to show nuclear export and translation of circular repeat-containing C9ORF72 intronic RNA.
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