1
|
Yadav P, Tamilselvan R, Mani H, Singh KK. MicroRNA-mediated regulation of nonsense-mediated mRNA decay factors: Insights into microRNA prediction tools and profiling techniques. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2024; 1867:195022. [PMID: 38437914 DOI: 10.1016/j.bbagrm.2024.195022] [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: 10/20/2023] [Revised: 02/28/2024] [Accepted: 03/01/2024] [Indexed: 03/06/2024]
Abstract
Nonsense-mediated mRNA decay (NMD) stands out as a prominent RNA surveillance mechanism within eukaryotes, meticulously overseeing both RNA abundance and integrity by eliminating aberrant transcripts. These defective transcripts are discerned through the concerted efforts of translating ribosomes, eukaryotic release factors (eRFs), and trans-acting NMD factors, with Up-Frameshift 3 (UPF3) serving as a noteworthy component. Remarkably, in humans, UPF3 exists in two paralogous forms, UPF3A (UPF3) and UPF3B (UPF3X). Beyond its role in quality control, UPF3 wields significant influence over critical cellular processes, including neural development, synaptic plasticity, and axon guidance. However, the precise regulatory mechanisms governing UPF3 remain elusive. MicroRNAs (miRNAs) emerge as pivotal post-transcriptional gene regulators, exerting substantial impact on diverse pathological and physiological pathways. This comprehensive review encapsulates our current understanding of the intricate regulatory nexus between NMD and miRNAs, with particular emphasis on the essential role played by UPF3B in neurodevelopment. Additionally, we bring out the significance of the 3'-untranslated region (3'-UTR) as the molecular bridge connecting NMD and miRNA-mediated gene regulation. Furthermore, we provide an in-depth exploration of diverse computational tools tailored for the prediction of potential miRNA targets. To complement these computational approaches, we delineate experimental techniques designed to validate predicted miRNA-mRNA interactions, empowering readers with the knowledge necessary to select the most appropriate methodology for their specific research objectives.
Collapse
Affiliation(s)
- Priyanka Yadav
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Raja Tamilselvan
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Harita Mani
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Kusum Kumari Singh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
| |
Collapse
|
2
|
Lai S, Shiraishi H, Sebastian WA, Shimizu N, Umeda R, Ikeuchi M, Kiyota K, Takeno T, Miyazaki S, Yano S, Shimada T, Yoshimura A, Hanada R, Hanada T. Effect of nonsense-mediated mRNA decay factor SMG9 deficiency on premature aging in zebrafish. Commun Biol 2024; 7:654. [PMID: 38806677 PMCID: PMC11133409 DOI: 10.1038/s42003-024-06356-6] [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: 06/20/2023] [Accepted: 05/20/2024] [Indexed: 05/30/2024] Open
Abstract
SMG9 is an essential component of the nonsense-mediated mRNA decay (NMD) machinery, a quality control mechanism that selectively degrades aberrant transcripts. Mutations in SMG9 are associated with heart and brain malformation syndrome (HBMS). However, the molecular mechanism underlying HBMS remains unclear. We generated smg9 mutant zebrafish (smg9oi7/oi7) that have a lifespan of approximately 6 months or longer, allowing for analysis of the in vivo function of Smg9 in adults in more detail. smg9oi7/oi7 zebrafish display congenital brain abnormalities and reduced cardiac contraction. Additionally, smg9oi7/oi7 zebrafish exhibit a premature aging phenotype. Analysis of NMD target mRNAs shows a trend toward increased mRNA levels in smg9oi7/oi7 zebrafish. Spermidine oxidase (Smox) is increased in smg9oi7/oi7 zebrafish, resulting in the accumulation of byproducts, reactive oxygen species, and acrolein. The accumulation of smox mRNA due to NMD dysregulation caused by Smg9 deficiency leads to increased oxidative stress, resulting in premature aging.
Collapse
Affiliation(s)
- Shaohong Lai
- Department of Cell Biology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Hiroshi Shiraishi
- Department of Cell Biology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | | | - Nobuyuki Shimizu
- Department of Cell Biology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Ryohei Umeda
- Department of Neurophysiology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Mayo Ikeuchi
- Department of Cell Biology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Kyoko Kiyota
- Department of Cell Biology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Takashi Takeno
- Department of Cell Biology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Shuya Miyazaki
- Department of Cell Biology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Shinji Yano
- Institute for Research Management, Oita University, Yufu, Oita, Japan
| | - Tatsuo Shimada
- Oita Medical Technology School, Japan College of Judo-Therapy, Acupuncture & Moxibustion Therapy, Oita, Japan
| | - Akihiko Yoshimura
- Department of Microbiology and Immunology, Keio University School of Medicine, Tokyo, Japan
| | - Reiko Hanada
- Department of Neurophysiology, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Toshikatsu Hanada
- Department of Cell Biology, Oita University Faculty of Medicine, Yufu, Oita, Japan.
| |
Collapse
|
3
|
Das R, Panigrahi GK. Messenger RNA Surveillance: Current Understanding, Regulatory Mechanisms, and Future Implications. Mol Biotechnol 2024:10.1007/s12033-024-01062-4. [PMID: 38411790 DOI: 10.1007/s12033-024-01062-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 01/02/2024] [Indexed: 02/28/2024]
Abstract
Nonsense-mediated mRNA decay (NMD) is an evolutionarily conserved surveillance mechanism in eukaryotes primarily deployed to ensure RNA quality control by eliminating aberrant transcripts and also involved in modulating the expression of several physiological transcripts. NMD, the mRNA surveillance pathway, is a major form of gene regulation in eukaryotes. NMD serves as one of the most significant quality control mechanisms as it primarily scans the newly synthesized transcripts and differentiates the aberrant and non-aberrant transcripts. The synthesis of truncated proteins is restricted, which would otherwise lead to cellular dysfunctions. The up-frameshift factors (UPFs) play a central role in executing the NMD event, largely by recognizing and recruiting multiple protein factors that result in the decay of non-physiological mRNAs. NMD exhibits astounding variability in its ability across eukaryotes in an array of pathological and physiological contexts. The detailed understanding of NMD and the underlying molecular mechanisms remains blurred. This review outlines our current understanding of NMD, in regulating multifaceted cellular events during development and disease. It also attempts to identify unanswered questions that deserve further investigation.
Collapse
Affiliation(s)
- Rutupurna Das
- Department of Zoology, School of Applied Sciences, Centurion University of Technology and Management, Jatni, Khordha, Odisha, India
| | - Gagan Kumar Panigrahi
- Department of Zoology, School of Applied Sciences, Centurion University of Technology and Management, Jatni, Khordha, Odisha, India.
| |
Collapse
|
4
|
Burkart V, Kowalski K, Disch A, Hilfiker-Kleiner D, Lal S, Dos Remedios C, Perrot A, Zeug A, Ponimaskin E, Kosanke M, Dittrich-Breiholz O, Kraft T, Montag J. Nonsense mediated decay factor UPF3B is associated with cMyBP-C haploinsufficiency in hypertrophic cardiomyopathy patients. J Mol Cell Cardiol 2023; 185:26-37. [PMID: 37797718 DOI: 10.1016/j.yjmcc.2023.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/08/2023] [Accepted: 09/28/2023] [Indexed: 10/07/2023]
Abstract
Hypertrophic cardiomyopathy (HCM) is the most prevalent inherited cardiac disease. Up to 40% of cases are associated with heterozygous mutations in myosin binding protein C (cMyBP-C, MYBPC3). Most of these mutations lead to premature termination codons (PTC) and patients show reduction of functional cMyBP-C. This so-called haploinsufficiency most likely contributes to disease development. We analyzed mechanisms underlying haploinsufficiency using cardiac tissue from HCM-patients with truncation mutations in MYBPC3 (MYBPC3trunc). We compared transcriptional activity, mRNA and protein expression to donor controls. To differentiate between HCM-specific and general hypertrophy-induced mechanisms we used patients with left ventricular hypertrophy due to aortic stenosis (AS) as an additional control. We show that cMyBP-C haploinsufficiency starts at the mRNA level, despite hypertrophy-induced increased transcriptional activity. Gene set enrichment analysis (GSEA) of RNA-sequencing data revealed an increased expression of NMD-components. Among them, Up-frameshift protein UPF3B, a regulator of NMD was upregulated in MYBPC3trunc patients and not in AS-patients. Strikingly, we show that in sarcomeres UPF3B but not UPF1 and UPF2 are localized to the Z-discs, the presumed location of sarcomeric protein translation. Our data suggest that cMyBP-C haploinsufficiency in HCM-patients is established by UPF3B-dependent NMD during the initial translation round at the Z-disc.
Collapse
Affiliation(s)
- Valentin Burkart
- Institute for Molecular and Cell Physiology, Hannover Medical School, Hannover, Germany.
| | - Kathrin Kowalski
- Institute for Molecular and Cell Physiology, Hannover Medical School, Hannover, Germany
| | - Alina Disch
- Institute for Molecular and Cell Physiology, Hannover Medical School, Hannover, Germany
| | | | - Sean Lal
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - Cristobal Dos Remedios
- Mechanosensory Biophysics Laboratory, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
| | - Andreas Perrot
- Charité - Universitätsmedizin Berlin, Experimental & Clinical Research Center, Berlin, Germany
| | - Andre Zeug
- Institute of Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Evgeni Ponimaskin
- Institute of Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Maike Kosanke
- Research Core Unit Genomics, Hannover Medical School, Hannover, Germany
| | | | - Theresia Kraft
- Institute for Molecular and Cell Physiology, Hannover Medical School, Hannover, Germany
| | - Judith Montag
- Institute for Molecular and Cell Physiology, Hannover Medical School, Hannover, Germany
| |
Collapse
|
5
|
Carrard J, Lejeune F. Nonsense-mediated mRNA decay, a simplified view of a complex mechanism. BMB Rep 2023; 56:625-632. [PMID: 38052423 PMCID: PMC10761751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 10/31/2023] [Accepted: 11/17/2023] [Indexed: 12/07/2023] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is both a quality control mechanism and a gene regulation pathway. It has been studied for more than 30 years, with an accumulation of many mechanistic details that have often led to debate and hence to different models of NMD activation, particularly in higher eukaryotes. Two models seem to be opposed, since the first requires intervention of the exon junction complex (EJC) to recruit NMD factors downstream of the premature termination codon (PTC), whereas the second involves an EJC-independent mechanism in which NMD factors concentrate in the 3'UTR to initiate NMD in the presence of a PTC. In this review we describe both models, giving recent molecular details and providing experimental arguments supporting one or the other model. In the end it is certainly possible to imagine that these two mechanisms co-exist, rather than viewing them as mutually exclusive. [BMB Reports 2023; 56(12): 625-632].
Collapse
Affiliation(s)
- Julie Carrard
- Univ. Lille, CNRS, Inserm, UMR9020-U1277 - CANTHER - Cancer Heterogeneity Plasticity and Resistance to Therapies, Lille F-59000, France
| | - Fabrice Lejeune
- Univ. Lille, CNRS, Inserm, UMR9020-U1277 - CANTHER - Cancer Heterogeneity Plasticity and Resistance to Therapies, Lille F-59000, France
| |
Collapse
|
6
|
Patro I, Sahoo A, Nayak BR, Das R, Majumder S, Panigrahi GK. Nonsense-Mediated mRNA Decay: Mechanistic Insights and Physiological Significance. Mol Biotechnol 2023:10.1007/s12033-023-00927-4. [PMID: 37930508 DOI: 10.1007/s12033-023-00927-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 09/28/2023] [Indexed: 11/07/2023]
Abstract
Nonsense-mediated mRNA decay (NMD) is an evolutionarily conserved surveillance mechanism across eukaryotes and also regulates the expression of physiological transcripts, thus involved in gene regulation. It essentially ensures recognition and removal of aberrant transcripts. Therefore, the NMD protects the cellular system by restricting the synthesis of truncated proteins, potentially by eliminating the faulty mRNAs. NMD is an evolutionarily conserved surveillance mechanism across eukaryotes and also regulates the expression of physiological transcripts, thus involved in gene regulation as well. Primarily, the NMD machinery scans and differentiates the aberrant and non-aberrant transcripts. A myriad of cellular dysfunctions arise due to production of truncated proteins, so the NMD core proteins, the up-frameshift factors (UPFs) recognizes the faulty mRNAs and further recruits factors resulting in the mRNA degradation. NMD exhibits astounding variability in its ability in regulating cellular mechanisms including both pathological and physiological events. But, the detailed underlying molecular mechanisms in NMD remains blurred and require extensive investigation to gain insights on cellular homeostasis. The complexity in understanding of NMD pathway arises due to the involvement of numerous proteins, molecular interactions and their functioning in different steps of this process. Moreover methods such as alternative splicing generates numerous isoforms of mRNA, so it makes difficulties in understanding the impact of alternative splicing on the efficiency of NMD functioning. Role of NMD in cancer development is very complex. Studies have shown that in some cases cancer cells use NMD pathway as a tool to exploit the NMD mechanism to maintain tumor microenvironment. A greater level of understanding about the intricate mechanism of how tumor used NMD pathway for their benefits, a strategy can be developed for targeting and inhibiting NMD factors involved in pro-tumor activity. There are very little amount of information available about the NMD pathway, how it discriminate mRNAs that are targeted by NMD from those that are not. This review highlights our current understanding of NMD, specifically the regulatory mechanisms and attempts to outline less explored questions that warrant further investigations. Taken as a whole, a detailed molecular understanding of the NMD mechanism could lead to wide-ranging applications for improving cellular homeostasis and paving out strategies in combating pathological disorders leaping forward toward achieving United Nations sustainable development goals (SDG 3: Good health and well-being).
Collapse
Affiliation(s)
- Ipsita Patro
- School of Applied Sciences, Centurion University of Technology and Management, Bhubaneswar, Odisha, India
| | - Annapurna Sahoo
- School of Applied Sciences, Centurion University of Technology and Management, Bhubaneswar, Odisha, India.
| | - Bilash Ranjan Nayak
- School of Applied Sciences, Centurion University of Technology and Management, Bhubaneswar, Odisha, India
| | - Rutupurna Das
- School of Applied Sciences, Centurion University of Technology and Management, Bhubaneswar, Odisha, India
| | - Sanjoy Majumder
- School of Applied Sciences, Centurion University of Technology and Management, Bhubaneswar, Odisha, India
| | - Gagan Kumar Panigrahi
- School of Applied Sciences, Centurion University of Technology and Management, Bhubaneswar, Odisha, India.
| |
Collapse
|
7
|
Monaghan L, Longman D, Cáceres JF. Translation-coupled mRNA quality control mechanisms. EMBO J 2023; 42:e114378. [PMID: 37605642 PMCID: PMC10548175 DOI: 10.15252/embj.2023114378] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/24/2023] [Accepted: 08/01/2023] [Indexed: 08/23/2023] Open
Abstract
mRNA surveillance pathways are essential for accurate gene expression and to maintain translation homeostasis, ensuring the production of fully functional proteins. Future insights into mRNA quality control pathways will enable us to understand how cellular mRNA levels are controlled, how defective or unwanted mRNAs can be eliminated, and how dysregulation of these can contribute to human disease. Here we review translation-coupled mRNA quality control mechanisms, including the non-stop and no-go mRNA decay pathways, describing their mechanisms, shared trans-acting factors, and differences. We also describe advances in our understanding of the nonsense-mediated mRNA decay (NMD) pathway, highlighting recent mechanistic findings, the discovery of novel factors, as well as the role of NMD in cellular physiology and its impact on human disease.
Collapse
Affiliation(s)
- Laura Monaghan
- MRC Human Genetics Unit, Institute of Genetics and CancerUniversity of EdinburghEdinburghUK
| | - Dasa Longman
- MRC Human Genetics Unit, Institute of Genetics and CancerUniversity of EdinburghEdinburghUK
| | - Javier F Cáceres
- MRC Human Genetics Unit, Institute of Genetics and CancerUniversity of EdinburghEdinburghUK
| |
Collapse
|
8
|
Halbout M, Bury M, Hanet A, Gerin I, Graff J, Killian T, Gatto L, Vertommen D, Bommer GT. SUZ domain-containing proteins have multiple effects on nonsense-mediated decay target transcripts. J Biol Chem 2023; 299:105095. [PMID: 37507022 PMCID: PMC10470013 DOI: 10.1016/j.jbc.2023.105095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
Many transcripts are targeted by nonsense-mediated decay (NMD), leading to their degradation and the inhibition of their translation. We found that the protein SUZ domain-containing protein 1 (SZRD1) interacts with the key NMD factor up-frameshift 1. When recruited to NMD-sensitive reporter gene transcripts, SZRD1 increased protein production, at least in part, by relieving translational inhibition. The conserved SUZ domain in SZRD1 was required for this effect. The SUZ domain is present in only three other human proteins besides SZRD1: R3H domain-containing protein 1 and 2 (R3HDM1, R3HDM2) and cAMP-regulated phosphoprotein 21 (ARPP21). We found that ARPP21, similarly to SZRD1, can increase protein production from NMD-sensitive reporter transcripts in an SUZ domain-dependent manner. This indicated that the SUZ domain-containing proteins could prevent translational inhibition of transcripts targeted by NMD. Consistent with the idea that SZRD1 mainly prevents translational inhibition, we did not observe a systematic decrease in the abundance of NMD targets when we knocked down SZRD1. Surprisingly, knockdown of SZRD1 in two different cell lines led to reduced levels of the NMD component UPF3B, which was accompanied by increased levels in a subset of NMD targets. This suggests that SZRD1 is required to maintain normal UPF3B levels and indicates that the effect of SZRD1 on NMD targets is not limited to a relief from translational inhibition. Overall, our study reveals that human SUZ domain-containing proteins play a complex role in regulating protein output from transcripts targeted by NMD.
Collapse
Affiliation(s)
- Mathias Halbout
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium
| | - Marina Bury
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium
| | - Aoife Hanet
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium
| | - Isabelle Gerin
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium
| | - Julie Graff
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium
| | - Theodore Killian
- Computational Biology Laboratory, de Duve Institute, UCLouvain, Bruxelles, Belgium
| | - Laurent Gatto
- Computational Biology Laboratory, de Duve Institute, UCLouvain, Bruxelles, Belgium
| | - Didier Vertommen
- Protein Phosphorylation Unit, de Duve Institute, UCLouvain, Brussels, Belgium
| | - Guido T Bommer
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium.
| |
Collapse
|
9
|
Chen C, Shen Y, Li L, Ren Y, Wang ZQ, Li T. UPF3A is dispensable for nonsense-mediated mRNA decay in mouse pluripotent and somatic cells. Life Sci Alliance 2023; 6:e202201589. [PMID: 36997282 PMCID: PMC10070813 DOI: 10.26508/lsa.202201589] [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: 07/04/2022] [Revised: 03/20/2023] [Accepted: 03/20/2023] [Indexed: 04/01/2023] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is a highly conserved regulatory mechanism of post-transcriptional gene expression in eukaryotic cells. NMD plays essential roles in mRNA quality and quantity control and thus safeguards multiple biological processes including embryonic stem cell differentiation and organogenesis. UPF3A and UPF3B in vertebrate species, originated from a single UPF3 gene in yeast, are key factors in the NMD machinery. Although UPF3B is a well-recognized weak NMD-promoting factor, whether UPF3A functions in promoting or suppressing NMD is under debate. In this study, we generated a Upf3a conditional knockout mouse strain and established multiple lines of embryonic stem cells and somatic cells without UPF3A. Through extensive analysis on the expressions of 33 NMD targets, we found UPF3A neither represses NMD in mouse embryonic stem cells, somatic cells, nor in major organs including the liver, spleen, and thymus. Our study reinforces that UPF3A is dispensable for NMD when UPF3B is present. Furthermore, UPF3A may weakly and selectively promote NMD in certain murine organs.
Collapse
Affiliation(s)
- Chengyan Chen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yanmin Shen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Luqian Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yaoxin Ren
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Zhao-Qi Wang
- Leibniz Institute on Aging - Fritz Lipmann Institute, Jena, Germany
| | - Tangliang Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
- School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| |
Collapse
|
10
|
Smith DM, Niehoff ML, Ling K, Jafar-Nejad P, Rigo F, Farr SA, Wilkinson MF, Nguyen AD. Targeting nonsense-mediated RNA decay does not increase progranulin levels in the Grn R493X mouse model of frontotemporal dementia. PLoS One 2023; 18:e0282822. [PMID: 36893203 PMCID: PMC9997918 DOI: 10.1371/journal.pone.0282822] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 02/23/2023] [Indexed: 03/10/2023] Open
Abstract
A common cause of frontotemporal dementia (FTD) are nonsense mutations in the progranulin (GRN) gene. Because nonsense mutations activate the nonsense-mediated RNA decay (NMD) pathway, we sought to inhibit this RNA turnover pathway as a means to increase progranulin levels. Using a knock-in mouse model harboring a common patient mutation, we tested whether either pharmacological or genetic inhibition of NMD upregulates progranulin in these GrnR493X mice. We first examined antisense oligonucleotides (ASOs) targeting an exonic region in GrnR493X mRNA predicted to block its degradation by NMD. As we previously reported, these ASOs effectively increased GrnR493X mRNA levels in fibroblasts in vitro. However, following CNS delivery, we found that none of the 8 ASOs we tested increased Grn mRNA levels in the brains of GrnR493X mice. This result was obtained despite broad ASO distribution in the brain. An ASO targeting a different mRNA was effective when administered in parallel to wild-type mice. As an independent approach to inhibit NMD, we examined the effect of loss of an NMD factor not required for embryonic viability: UPF3b. We found that while Upf3b deletion effectively perturbed NMD, it did not increase Grn mRNA levels in Grn+/R493X mouse brains. Together, our results suggest that the NMD-inhibition approaches that we used are likely not viable for increasing progranulin levels in individuals with FTD caused by nonsense GRN mutations. Thus, alternative approaches should be pursued.
Collapse
Affiliation(s)
- Denise M. Smith
- Division of Geriatric Medicine, Department of Internal Medicine, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Institute for Translational Neuroscience, Saint Louis University, St. Louis, Missouri, United States of America
| | - Michael L. Niehoff
- Division of Geriatric Medicine, Department of Internal Medicine, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Veterans Affairs Medical Center, St. Louis, Missouri, United States of America
| | - Karen Ling
- Ionis Pharmaceuticals, Carlsbad, California, United States of America
| | | | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, California, United States of America
| | - Susan A. Farr
- Division of Geriatric Medicine, Department of Internal Medicine, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Institute for Translational Neuroscience, Saint Louis University, St. Louis, Missouri, United States of America
- Veterans Affairs Medical Center, St. Louis, Missouri, United States of America
| | - Miles F. Wilkinson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California San Diego, La Jolla, California, United States of America
- Institute of Genomic Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Andrew D. Nguyen
- Division of Geriatric Medicine, Department of Internal Medicine, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
- Institute for Translational Neuroscience, Saint Louis University, St. Louis, Missouri, United States of America
| |
Collapse
|
11
|
Nonsense-Mediated mRNA Decay as a Mediator of Tumorigenesis. Genes (Basel) 2023; 14:genes14020357. [PMID: 36833284 PMCID: PMC9956241 DOI: 10.3390/genes14020357] [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: 12/05/2022] [Revised: 01/23/2023] [Accepted: 01/26/2023] [Indexed: 02/03/2023] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is an evolutionarily conserved and well-characterized biological mechanism that ensures the fidelity and regulation of gene expression. Initially, NMD was described as a cellular surveillance or quality control process to promote selective recognition and rapid degradation of erroneous transcripts harboring a premature translation-termination codon (PTC). As estimated, one-third of mutated and disease-causing mRNAs were reported to be targeted and degraded by NMD, suggesting the significance of this intricate mechanism in maintaining cellular integrity. It was later revealed that NMD also elicits down-regulation of many endogenous mRNAs without mutations (~10% of the human transcriptome). Therefore, NMD modulates gene expression to evade the generation of aberrant truncated proteins with detrimental functions, compromised activities, or dominant-negative effects, as well as by controlling the abundance of endogenous mRNAs. By regulating gene expression, NMD promotes diverse biological functions during development and differentiation, and facilitates cellular responses to adaptation, physiological changes, stresses, environmental insults, etc. Mutations or alterations (such as abnormal expression, degradation, post-translational modification, etc.) that impair the function or expression of proteins associated with the NMD pathway can be deleterious to cells and may cause pathological consequences, as implicated in developmental and intellectual disabilities, genetic defects, and cancer. Growing evidence in past decades has highlighted NMD as a critical driver of tumorigenesis. Advances in sequencing technologies provided the opportunity to identify many NMD substrate mRNAs in tumor samples compared to matched normal tissues. Interestingly, many of these changes are tumor-specific and are often fine-tuned in a tumor-specific manner, suggesting the complex regulation of NMD in cancer. Tumor cells differentially exploit NMD for survival benefits. Some tumors promote NMD to degrade a subset of mRNAs, such as those encoding tumor suppressors, stress response proteins, signaling proteins, RNA binding proteins, splicing factors, and immunogenic neoantigens. In contrast, some tumors suppress NMD to facilitate the expression of oncoproteins or other proteins beneficial for tumor growth and progression. In this review, we discuss how NMD is regulated as a critical mediator of oncogenesis to promote the development and progression of tumor cells. Understanding how NMD affects tumorigenesis differentially will pave the way for the development of more effective and less toxic, targeted therapeutic opportunities in the era of personalized medicine.
Collapse
|
12
|
Felhi R, Monastiri K, Ben Hamida H, Ammar M, Chioukh FZ, Tabarki B, Chouchen J, Fakhfakh F, Tlili A, Mkaouar-Rebai E. First description of the MEGDEHL syndrome in the Tunisian population via whole-exome sequencing: Novel nonsense mutation in SERAC1 gene. Int J Dev Neurosci 2022; 82:736-747. [PMID: 35943861 DOI: 10.1002/jdn.10223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 07/08/2022] [Accepted: 08/02/2022] [Indexed: 11/08/2022] Open
Abstract
INTRODUCTION MEGDEL syndrome is a rare recessive disorder, with about 100 cases reported worldwide, which is defined by 3-methylglutaconic aciduria (MEG), deafness (D), encephalopathy (E) and Leigh-like syndrome (L). When these manifestations were added to hepatopathy (H), the syndrome was labelled as MEGD(H)EL. Mutations in SERAC1 gene encoding a serine active site containing 1 protein were described in patients affected by this syndrome. PATIENTS AND METHODS The present study reports the Whole Exome Sequencing (WES) of the first case of MEGDEHL syndrome in Tunisia in a consanguineous family with three affected children. Bioinformatic analysis was also performed in addition to mtDNA deletion screening and mtDNA copy number quantification in the blood of the indexed case, carried out, respectively by Long-Range PCR and qPCR. RESULTS The WES revealed a novel homozygous nonsense mutation (c.1379G > A; p.W460X) in the SERAC1 gene, which was confirmed by Sanger sequencing. This nonsense mutation was present at a homozygous state in the three affected children and was heterozygous in the parents. In silico analysis using various softwares was performed, and the predictive results supported the pathogenic effect of the identified mutation. Further, long-range PCR and qPCR analyses of the patient's blood excluded any mtDNA deletions or depletions. CONCLUSION Sequencing results and bioinformatic tools confirmed that the novel mutation (p.W460X) in the SERAC1 gene causes the severe phenotype in the studied family with MEGDEHL syndrome.
Collapse
Affiliation(s)
- Rahma Felhi
- Molecular and Functional Genetics Laboratory, Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia
| | - Kamel Monastiri
- Maternity and Neonatology Center of Monastir, Faculty of Medicine of Monastir, Monastir, Tunisia
| | - Hayet Ben Hamida
- Maternity and Neonatology Center of Monastir, Faculty of Medicine of Monastir, Monastir, Tunisia
| | - Marwa Ammar
- Molecular and Functional Genetics Laboratory, Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia
| | - Fatma Zohra Chioukh
- Maternity and Neonatology Center of Monastir, Faculty of Medicine of Monastir, Monastir, Tunisia
| | - Brahim Tabarki
- Department of Pediatrics, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
| | - Jihene Chouchen
- Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Faiza Fakhfakh
- Molecular and Functional Genetics Laboratory, Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia
| | - Abdelaziz Tlili
- Department of Applied Biology, College of Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Emna Mkaouar-Rebai
- Molecular and Functional Genetics Laboratory, Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia
| |
Collapse
|
13
|
Chousal JN, Sohni A, Vitting-Seerup K, Cho K, Kim M, Tan K, Porse B, Wilkinson MF, Cook-Andersen H. Progression of the pluripotent epiblast depends upon the NMD factor UPF2. Development 2022; 149:dev200764. [PMID: 36255229 PMCID: PMC9687065 DOI: 10.1242/dev.200764] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 09/09/2022] [Indexed: 11/09/2022]
Abstract
Nonsense-mediated RNA decay (NMD) is a highly conserved RNA turnover pathway that degrades RNAs harboring in-frame stop codons in specific contexts. Loss of NMD factors leads to embryonic lethality in organisms spanning the phylogenetic scale, but the mechanism remains unknown. Here, we report that the core NMD factor, UPF2, is required for expansion of epiblast cells within the inner cell mass of mice in vivo. We identify NMD target mRNAs in mouse blastocysts - both canonical and alternatively processed mRNAs - including those encoding cell cycle arrest and apoptosis factors, raising the possibility that NMD is essential for embryonic cell proliferation and survival. In support, the inner cell mass of Upf2-null blastocysts rapidly regresses with outgrowth and is incompetent for embryonic stem cell derivation in vitro. In addition, we uncovered concordant temporal- and lineage-specific regulation of NMD factors and mRNA targets, indicative of a shift in NMD magnitude during peri-implantation development. Together, our results reveal developmental and molecular functions of the NMD pathway in the early embryo.
Collapse
Affiliation(s)
- Jennifer N. Chousal
- Department of Obstetrics, Gynecology and Reproductive Sciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Department of Molecular Biology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Abhishek Sohni
- Department of Obstetrics, Gynecology and Reproductive Sciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kristoffer Vitting-Seerup
- The Bioinformatics Centre, Department of Biology and Biotech Research & Innovation Centre, University of Copenhagen, 2200 Copenhagen, Denmark
- Section for Bioinformatics, Health Technology, Technical University of Denmark (DTU), 2800 Kongens Lyngby, Denmark
| | - Kyucheol Cho
- Department of Obstetrics, Gynecology and Reproductive Sciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Department of Molecular Biology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Matthew Kim
- Department of Obstetrics, Gynecology and Reproductive Sciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kun Tan
- Department of Obstetrics, Gynecology and Reproductive Sciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Bo Porse
- The Finsen Laboratory, Rigshospitalet, Faculty of Health Sciences, University of Copenhagen, DK2200 Copenhagen, Denmark
- Biotech Research and Innovation Center (BRIC), University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Stem Cell Biology, DanStem, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Miles F. Wilkinson
- Department of Obstetrics, Gynecology and Reproductive Sciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Heidi Cook-Andersen
- Department of Obstetrics, Gynecology and Reproductive Sciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Department of Molecular Biology, University of California, San Diego, La Jolla, CA 92093, USA
| |
Collapse
|
14
|
Tan K, Stupack DG, Wilkinson MF. Nonsense-mediated RNA decay: an emerging modulator of malignancy. Nat Rev Cancer 2022; 22:437-451. [PMID: 35624152 PMCID: PMC11009036 DOI: 10.1038/s41568-022-00481-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/19/2022] [Indexed: 12/11/2022]
Abstract
Nonsense-mediated RNA decay (NMD) is a highly conserved RNA turnover pathway that selectively degrades RNAs harbouring truncating mutations that prematurely terminate translation, including nonsense, frameshift and some splice-site mutations. Recent studies show that NMD shapes the mutational landscape of tumours by selecting for mutations that tend to downregulate the expression of tumour suppressor genes but not oncogenes. This suggests that NMD can benefit tumours, a notion further supported by the finding that mRNAs encoding immunogenic neoantigen peptides are typically targeted for decay by NMD. Together, this raises the possibility that NMD-inhibitory therapy could be of therapeutic benefit against many tumour types, including those with a high load of neoantigen-generating mutations. Complicating this scenario is the evidence that NMD can also be detrimental for many tumour types, and consequently tumours often have perturbed NMD. NMD may suppress tumour generation and progression by degrading subsets of specific normal mRNAs, including those encoding stress-response proteins, signalling factors and other proteins beneficial for tumours, as well as pro-tumour non-coding RNAs. Together, these findings suggest that NMD-modulatory therapy has the potential to provide widespread therapeutic benefit against diverse tumour types. However, whether NMD should be stimulated or repressed requires careful analysis of the tumour to be treated.
Collapse
Affiliation(s)
- Kun Tan
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Dwayne G Stupack
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, CA, USA.
- UCSD Moores Cancer Center, University of California, San Diego, La Jolla, CA, USA.
| | - Miles F Wilkinson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, CA, USA.
- Institute of Genomic Medicine, University of California, San Diego, La Jolla, CA, USA.
| |
Collapse
|
15
|
Fritz SE, Ranganathan S, Wang CD, Hogg JR. An alternative UPF1 isoform drives conditional remodeling of nonsense-mediated mRNA decay. EMBO J 2022; 41:e108898. [PMID: 35403729 PMCID: PMC9108617 DOI: 10.15252/embj.2021108898] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 03/18/2022] [Accepted: 03/25/2022] [Indexed: 12/11/2022] Open
Abstract
The nonsense-mediated mRNA decay (NMD) pathway monitors translation termination in order to degrade transcripts with premature stop codons and regulate thousands of human genes. Here, we show that an alternative mammalian-specific isoform of the core NMD factor UPF1, termed UPF1LL , enables condition-dependent remodeling of NMD specificity. Previous studies indicate that the extension of a conserved regulatory loop in the UPF1LL helicase core confers a decreased propensity to dissociate from RNA upon ATP hydrolysis relative to UPF1SL , the major UPF1 isoform. Using biochemical and transcriptome-wide approaches, we find that UPF1LL can circumvent the protective RNA binding proteins PTBP1 and hnRNP L to preferentially bind and down-regulate transcripts with long 3'UTRs normally shielded from NMD. Unexpectedly, UPF1LL supports induction of NMD on new populations of substrate mRNAs in response to activation of the integrated stress response and impaired translation efficiency. Thus, while canonical NMD is abolished by moderate translational repression, UPF1LL activity is enhanced, offering the possibility to rapidly rewire NMD specificity in response to cellular stress.
Collapse
Affiliation(s)
- Sarah E Fritz
- Biochemistry and Biophysics CenterNational Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Soumya Ranganathan
- Biochemistry and Biophysics CenterNational Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - Clara D Wang
- Biochemistry and Biophysics CenterNational Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| | - J Robert Hogg
- Biochemistry and Biophysics CenterNational Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMDUSA
| |
Collapse
|
16
|
Mailliot J, Vivoli-Vega M, Schaffitzel C. No-nonsense: insights into the functional interplay of nonsense-mediated mRNA decay factors. Biochem J 2022; 479:973-993. [PMID: 35551602 PMCID: PMC9162471 DOI: 10.1042/bcj20210556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 04/10/2022] [Accepted: 04/12/2022] [Indexed: 11/22/2022]
Abstract
Nonsense-mediated messenger RNA decay (NMD) represents one of the main surveillance pathways used by eukaryotic cells to control the quality and abundance of mRNAs and to degrade viral RNA. NMD recognises mRNAs with a premature termination codon (PTC) and targets them to decay. Markers for a mRNA with a PTC, and thus NMD, are a long a 3'-untranslated region and the presence of an exon-junction complex (EJC) downstream of the stop codon. Here, we review our structural understanding of mammalian NMD factors and their functional interplay leading to a branched network of different interconnected but specialised mRNA decay pathways. We discuss recent insights into the potential impact of EJC composition on NMD pathway choice. We highlight the coexistence and function of different isoforms of up-frameshift protein 1 (UPF1) with an emphasis of their role at the endoplasmic reticulum and during stress, and the role of the paralogs UPF3B and UPF3A, underscoring that gene regulation by mammalian NMD is tightly controlled and context-dependent being conditional on developmental stage, tissue and cell types.
Collapse
Affiliation(s)
- Justine Mailliot
- School of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K
| | - Mirella Vivoli-Vega
- School of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K
| | - Christiane Schaffitzel
- School of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K
- Bristol Synthetic Biology Centre BrisSynBio, 24 Tyndall Ave, Bristol BS8 1TQ, U.K
| |
Collapse
|
17
|
Sanderlin EJ, Keenan MM, Mense M, Revenko AS, Monia BP, Guo S, Huang L. CFTR mRNAs with nonsense codons are degraded by the SMG6-mediated endonucleolytic decay pathway. Nat Commun 2022; 13:2344. [PMID: 35487895 PMCID: PMC9054838 DOI: 10.1038/s41467-022-29935-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 03/24/2022] [Indexed: 12/22/2022] Open
Abstract
Approximately 10% of cystic fibrosis patients harbor nonsense mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene which can generate nonsense codons in the CFTR mRNA and subsequently activate the nonsense-mediated decay (NMD) pathway resulting in rapid mRNA degradation. However, it is not known which NMD branches govern the decay of CFTR mRNAs containing nonsense codons. Here we utilize antisense oligonucleotides targeting NMD factors to evaluate the regulation of nonsense codon-containing CFTR mRNAs by the NMD pathway. We observe that CFTR mRNAs with nonsense codons G542X, R1162X, and W1282X, but not Y122X, require UPF2 and UPF3 for NMD. Furthermore, we demonstrate that all evaluated CFTR mRNAs harboring nonsense codons are degraded by the SMG6-mediated endonucleolytic pathway rather than the SMG5-SMG7-mediated exonucleolytic pathway. Finally, we show that upregulation of all evaluated CFTR mRNAs with nonsense codons by NMD pathway inhibition improves outcomes of translational readthrough therapy.
Collapse
Affiliation(s)
| | | | - Martin Mense
- Cystic Fibrosis Foundation Therapeutics Lab, Cystic Fibrosis Foundation, Lexington, MA, USA
| | | | | | - Shuling Guo
- Ionis Pharmaceuticals, Inc., Carlsbad, CA, USA
| | - Lulu Huang
- Ionis Pharmaceuticals, Inc., Carlsbad, CA, USA.
| |
Collapse
|
18
|
Yi Z, Arvola RM, Myers S, Dilsavor CN, Abu Alhasan R, Carter BN, Patton RD, Bundschuh R, Singh G. Mammalian UPF3A and UPF3B can activate nonsense-mediated mRNA decay independently of their exon junction complex binding. EMBO J 2022; 41:e109202. [PMID: 35451102 PMCID: PMC9108626 DOI: 10.15252/embj.2021109202] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 03/21/2022] [Accepted: 03/31/2022] [Indexed: 12/30/2022] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is governed by the three conserved factors-UPF1, UPF2, and UPF3. While all three are required for NMD in yeast, UPF3B is dispensable for NMD in mammals, and its paralog UPF3A is suggested to only weakly activate or even repress NMD due to its weaker binding to the exon junction complex (EJC). Here, we characterize the UPF3A/B-dependence of NMD in human cell lines deleted of one or both UPF3 paralogs. We show that in human colorectal cancer HCT116 cells, NMD can operate in a UPF3B-dependent and -independent manner. While UPF3A is almost dispensable for NMD in wild-type cells, it strongly activates NMD in cells lacking UPF3B. Notably, NMD remains partially active in cells lacking both UPF3 paralogs. Complementation studies in these cells show that EJC-binding domain of UPF3 paralogs is dispensable for NMD. Instead, the conserved "mid" domain of UPF3 paralogs is consequential for their NMD activity. Altogether, our results demonstrate that the mammalian UPF3 proteins play a more active role in NMD than simply bridging the EJC and the UPF complex.
Collapse
Affiliation(s)
- Zhongxia Yi
- Center for RNA Biology, The Ohio State University, Columbus, OH, USA.,Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - René M Arvola
- Center for RNA Biology, The Ohio State University, Columbus, OH, USA.,Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - Sean Myers
- Department of Physics, The Ohio State University, Columbus, OH, USA
| | - Corinne N Dilsavor
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - Rabab Abu Alhasan
- Center for RNA Biology, The Ohio State University, Columbus, OH, USA.,Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - Bayley N Carter
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - Robert D Patton
- Center for RNA Biology, The Ohio State University, Columbus, OH, USA.,Department of Physics, The Ohio State University, Columbus, OH, USA
| | - Ralf Bundschuh
- Center for RNA Biology, The Ohio State University, Columbus, OH, USA.,Department of Physics, The Ohio State University, Columbus, OH, USA.,Department of Chemistry and Biochemistry, The Ohio State University , Columbus, OH, USA.,Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, OH, USA
| | - Guramrit Singh
- Center for RNA Biology, The Ohio State University, Columbus, OH, USA.,Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| |
Collapse
|
19
|
The Physiological Roles of the Exon Junction Complex in Development and Diseases. Cells 2022; 11:cells11071192. [PMID: 35406756 PMCID: PMC8997533 DOI: 10.3390/cells11071192] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/19/2022] [Accepted: 03/24/2022] [Indexed: 01/12/2023] Open
Abstract
The exon junction complex (EJC) becomes an increasingly important regulator of early gene expression in the central nervous system (CNS) and other tissues. The EJC is comprised of three core proteins: RNA-binding motif 8A (RBM8A), Mago homolog (MAGOH), eukaryotic initiation factor 4A3 (EIF4A3), and a peripheral EJC factor, metastatic lymph node 51 (MLN51), together with various auxiliary factors. The EJC is assembled specifically at exon-exon junctions on mRNAs, hence the name of the complex. The EJC regulates multiple levels of gene expression, from splicing to translation and mRNA degradation. The functional roles of the EJC have been established as crucial to the normal progress of embryonic and neurological development, with wide ranging implications on molecular, cellular, and organism level function. Dysfunction of the EJC has been implicated in multiple developmental and neurological diseases. In this review, we discuss recent progress on the EJC’s physiological roles.
Collapse
|
20
|
Abdel-Salam GMH, Duan R, Abdel-Hamid MS, Sayed ISM, Jhangiani SN, Khan Z, Du H, Gibbs RA, Posey JE, Marafi D, Lupski JR. Expanding the phenotypic and allelic spectrum of SMG8: Clinical observations reveal overlap with SMG9-associated disease trait. Am J Med Genet A 2021; 188:648-657. [PMID: 34761517 DOI: 10.1002/ajmg.a.62561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/03/2021] [Accepted: 10/22/2021] [Indexed: 11/06/2022]
Abstract
SMG8 (MIM *617315) is a regulatory subunit involved in nonsense-mediated mRNA decay (NMD), a cellular protective pathway that regulates mRNA transcription, transcript stability, and degrades transcripts containing premature stop codons. SMG8 binds SMG9 and SMG1 to form the SMG1C complex and inhibit the kinase activity of SMG1. Biallelic deleterious variants in SMG9 are known to cause a heart and brain malformation syndrome (HBMS; MIM #616920), whereas biallelic deleterious variants in SMG8 were recently described to cause a novel neurodevelopmental disorder (NDD) with dysmorphic facies and cataracts, now defined as Alzahrani-Kuwahara syndrome (ALKUS: MIM #619268). Only eight subjects from four families with ALKUS have been described to date. Through research reanalysis of a nondiagnostic clinical exome, we identified a subject from a fifth unrelated family with a homozygous deleterious variant in SMG8 and features consistent with ALKUS. Interestingly, the subject also had unilateral microphthalmia, a clinical feature that has been described in SMG9-related disorder. Our study expands the phenotypic spectrum of SMG8-related disorder, demonstrates an overlapping phenotype between SMG8- and SMG9-related rare disease traits, provides further evidence for the SMG8 and SMG9 protein interactions, and highlights the importance of revisiting nondiagnostic exome data to identify and affirm emerging novel genes for rare disease traits.
Collapse
Affiliation(s)
- Ghada M H Abdel-Salam
- Clinical Genetics Department, Human Genetics and Genome Research Division, National ResearchCentre, Cairo, Egypt
| | - Ruizhi Duan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Mohamed S Abdel-Hamid
- Medical Molecular Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Inas S M Sayed
- Orodental Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Shalini N Jhangiani
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA
| | - Ziad Khan
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA
| | - Haowei Du
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Richard A Gibbs
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA
| | - Jennifer E Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Dana Marafi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Department of Pediatrics, Faculty of Medicine, Kuwait University, Safat, Kuwait
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA.,Texas Children's Hospital, Houston, Texas, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| |
Collapse
|
21
|
Palma M, Leroy C, Salomé-Desnoulez S, Werkmeister E, Kong R, Mongy M, Le Hir H, Lejeune F. A role for AKT1 in nonsense-mediated mRNA decay. Nucleic Acids Res 2021; 49:11022-11037. [PMID: 34634811 PMCID: PMC8565340 DOI: 10.1093/nar/gkab882] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 12/16/2022] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is a highly regulated quality control mechanism through which mRNAs harboring a premature termination codon are degraded. It is also a regulatory pathway for some genes. This mechanism is subject to various levels of regulation, including phosphorylation. To date only one kinase, SMG1, has been described to participate in NMD, by targeting the central NMD factor UPF1. Here, screening of a kinase inhibitor library revealed as putative NMD inhibitors several molecules targeting the protein kinase AKT1. We present evidence demonstrating that AKT1, a central player in the PI3K/AKT/mTOR signaling pathway, plays an essential role in NMD, being recruited by the UPF3X protein to phosphorylate UPF1. As AKT1 is often overactivated in cancer cells and as this should result in increased NMD efficiency, the possibility that this increase might affect cancer processes and be targeted in cancer therapy is discussed.
Collapse
Affiliation(s)
- Martine Palma
- Univ. Lille, CNRS, Inserm, CHU Lille, UMR9020-U1277 - CANTHER - Cancer Heterogeneity Plasticity and Resistance to Therapies, F-59000 Lille, France.,Unité tumorigenèse et résistance aux traitements, Institut Pasteur de Lille, F-59000 Lille, France
| | - Catherine Leroy
- Univ. Lille, CNRS, Inserm, CHU Lille, UMR9020-U1277 - CANTHER - Cancer Heterogeneity Plasticity and Resistance to Therapies, F-59000 Lille, France.,Unité tumorigenèse et résistance aux traitements, Institut Pasteur de Lille, F-59000 Lille, France
| | - Sophie Salomé-Desnoulez
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41 - UMS 2014 - PLBS, F-59000 Lille, France
| | - Elisabeth Werkmeister
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41 - UMS 2014 - PLBS, F-59000 Lille, France.,Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR9017 - CIIL - center for Infection and Immunity of Lille, F-59000 Lille, France
| | - Rebekah Kong
- Univ. Lille, CNRS, Inserm, CHU Lille, UMR9020-U1277 - CANTHER - Cancer Heterogeneity Plasticity and Resistance to Therapies, F-59000 Lille, France.,Unité tumorigenèse et résistance aux traitements, Institut Pasteur de Lille, F-59000 Lille, France
| | - Marc Mongy
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41 - UMS 2014 - PLBS, F-59000 Lille, France
| | - Hervé Le Hir
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, 46 rue d'Ulm, 75005 Paris, France
| | - Fabrice Lejeune
- Univ. Lille, CNRS, Inserm, CHU Lille, UMR9020-U1277 - CANTHER - Cancer Heterogeneity Plasticity and Resistance to Therapies, F-59000 Lille, France.,Unité tumorigenèse et résistance aux traitements, Institut Pasteur de Lille, F-59000 Lille, France
| |
Collapse
|
22
|
Machado de Amorim A, Chakrabarti S. Assembly of multicomponent machines in RNA metabolism: A common theme in mRNA decay pathways. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 13:e1684. [PMID: 34351053 DOI: 10.1002/wrna.1684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/07/2021] [Accepted: 07/08/2021] [Indexed: 11/05/2022]
Abstract
Multicomponent protein-RNA complexes comprising a ribonuclease and partner RNA helicase facilitate the turnover of mRNA in all domains of life. While these higher-order complexes provide an effective means of physically and functionally coupling the processes of RNA remodeling and decay, most ribonucleases and RNA helicases do not exhibit sequence specificity in RNA binding. This raises the question as to how these assemblies select substrates for processing and how the activities are orchestrated at the precise moment to ensure efficient decay. The answers to these apparent puzzles lie in the auxiliary components of the assemblies that might relay decay-triggering signals. Given their function within the assemblies, these components may be viewed as "sensors." The functions and mechanisms of action of the sensor components in various degradation complexes in bacteria and eukaryotes are highlighted here to discuss their roles in RNA decay processes. This article is categorized under: RNA Turnover and Surveillance > Regulation of RNA Stability RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition.
Collapse
Affiliation(s)
| | - Sutapa Chakrabarti
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| |
Collapse
|
23
|
Ngo GHP, Grimstead JW, Baird DM. UPF1 promotes the formation of R loops to stimulate DNA double-strand break repair. Nat Commun 2021; 12:3849. [PMID: 34158508 PMCID: PMC8219777 DOI: 10.1038/s41467-021-24201-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 06/07/2021] [Indexed: 12/12/2022] Open
Abstract
DNA-RNA hybrid structures have been detected at the vicinity of DNA double-strand breaks (DSBs) occurring within transcriptional active regions of the genome. The induction of DNA-RNA hybrids strongly affects the repair of these DSBs, but the nature of these structures and how they are formed remain poorly understood. Here we provide evidence that R loops, three-stranded structures containing DNA-RNA hybrids and the displaced single-stranded DNA (ssDNA) can form at sub-telomeric DSBs. These R loops are generated independently of DNA resection but are induced alongside two-stranded DNA-RNA hybrids that form on ssDNA generated by DNA resection. We further identified UPF1, an RNA/DNA helicase, as a crucial factor that drives the formation of these R loops and DNA-RNA hybrids to stimulate DNA resection, homologous recombination, microhomology-mediated end joining and DNA damage checkpoint activation. Our data show that R loops and DNA-RNA hybrids are actively generated at DSBs to facilitate DNA repair.
Collapse
Affiliation(s)
- Greg H P Ngo
- Division of Cancer and Genetics, School of Medicine, Cardiff University, Cardiff, UK
| | - Julia W Grimstead
- Division of Cancer and Genetics, School of Medicine, Cardiff University, Cardiff, UK
| | - Duncan M Baird
- Division of Cancer and Genetics, School of Medicine, Cardiff University, Cardiff, UK.
| |
Collapse
|
24
|
Nogueira G, Fernandes R, García-Moreno JF, Romão L. Nonsense-mediated RNA decay and its bipolar function in cancer. Mol Cancer 2021; 20:72. [PMID: 33926465 PMCID: PMC8082775 DOI: 10.1186/s12943-021-01364-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 04/19/2021] [Indexed: 12/17/2022] Open
Abstract
Nonsense-mediated decay (NMD) was first described as a quality-control mechanism that targets and rapidly degrades aberrant mRNAs carrying premature termination codons (PTCs). However, it was found that NMD also degrades a significant number of normal transcripts, thus arising as a mechanism of gene expression regulation. Based on these important functions, NMD regulates several biological processes and is involved in the pathophysiology of a plethora of human genetic diseases, including cancer. The present review aims to discuss the paradoxical, pro- and anti-tumorigenic roles of NMD, and how cancer cells have exploited both functions to potentiate the disease. Considering recent genetic and bioinformatic studies, we also provide a comprehensive overview of the present knowledge of the advantages and disadvantages of different NMD modulation-based approaches in cancer therapy, reflecting on the challenges imposed by the complexity of this disease. Furthermore, we discuss significant advances in the recent years providing new perspectives on the implications of aberrant NMD-escaping frameshifted transcripts in personalized immunotherapy design and predictive biomarker optimization. A better understanding of how NMD differentially impacts tumor cells according to their own genetic identity will certainly allow for the application of novel and more effective personalized treatments in the near future.
Collapse
Affiliation(s)
- Gonçalo Nogueira
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016, Lisbon, Portugal.,BioISI - Instituto de Biossistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisbon, Portugal
| | - Rafael Fernandes
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016, Lisbon, Portugal.,BioISI - Instituto de Biossistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisbon, Portugal
| | - Juan F García-Moreno
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016, Lisbon, Portugal.,BioISI - Instituto de Biossistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisbon, Portugal
| | - Luísa Romão
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016, Lisbon, Portugal. .,BioISI - Instituto de Biossistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisbon, Portugal.
| |
Collapse
|
25
|
Hu J, Li P, Shi B, Tie J. Importin β1 mediates nuclear import of the factors associated with nonsense-mediated RNA decay. Biochem Biophys Res Commun 2021; 542:34-39. [PMID: 33486189 DOI: 10.1016/j.bbrc.2021.01.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 01/11/2021] [Indexed: 12/15/2022]
Abstract
In eukaryotic cells, nonsense-mediated RNA decay (NMD) is an essential physiological mechanism coupled to translation, regulating the stability of abnormal RNA containing premature termination codon (PTC) and a significant fraction of normal transcriptomes. So far, the molecular regulation mechanism of NMD pathway is far from fully elucidated. Previously, we observed the interaction between importin β1 (Impβ1) and UPF1, a core factor of NMD. Here, we demonstrated that Impβ1 knockdown stabilized NMD reporters, and Impβ1 and UPF1 interacted and co-regulated an extensive number of target transcripts. Furthermore, Impβ1 affected the interaction between UPF1 and SMG5 or MAGOH, and the nuclear distributions of UPF1, SMG1, SMG5 and MAGOH. Besides, Ran knockdown extremely promoted the dissociation of UPF1 from SMG5 or MAGOH. Our findings provide molecular insight into the potential function of Impβ1in nonsense-mediated RNA decay.
Collapse
Affiliation(s)
- Jianran Hu
- Department of Biological Science and Technology, Changzhi University, Changzhi, 046011, China.
| | - Ping Li
- Department of Biological Science and Technology, Changzhi University, Changzhi, 046011, China
| | - Baozhong Shi
- Department of Biological Science and Technology, Changzhi University, Changzhi, 046011, China
| | - Jun Tie
- Department of Biological Science and Technology, Changzhi University, Changzhi, 046011, China
| |
Collapse
|
26
|
Grosse S, Lu YY, Coban I, Neumann B, Krebber H. Nuclear SR-protein mediated mRNA quality control is continued in cytoplasmic nonsense-mediated decay. RNA Biol 2021; 18:1390-1407. [PMID: 33406982 PMCID: PMC8489946 DOI: 10.1080/15476286.2020.1851506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
One important task of eukaryotic cells is to translate only mRNAs that were correctly processed to prevent the production of truncated proteins, found in neurodegenerative diseases and cancer. Nuclear quality control of splicing requires the SR-like proteins Gbp2 and Hrb1 in S. cerevisiae, where they promote the degradation of faulty pre-mRNAs. Here we show that Gbp2 and Hrb1 also function in nonsense mediated decay (NMD) of spliced premature termination codon (PTC)-containing mRNAs. Our data support a model in which they are in a complex with the Upf-proteins and help to transmit the Upf1-mediated PTC recognition to the transcripts ends. Most importantly they appear to promote translation repression of spliced transcripts that contain a PTC and to finally facilitate degradation of the RNA, presumably by supporting the recruitment of the degradation factors. Therefore, they seem to control mRNA quality beyond the nuclear border and may thus be global surveillance factors. Identification of SR-proteins as general cellular surveillance factors in yeast will help to understand the complex human system in which many diseases with defects in SR-proteins or NMD are known, but the proteins were not yet recognized as general RNA surveillance factors.
Collapse
Affiliation(s)
- Sebastian Grosse
- Abteilung Für Molekulare Genetik, Institut Für Mikrobiologie Und Genetik, Göttinger Zentrum Für Molekulare Biowissenschaften (GZMB), Georg-August Universität Göttingen, Göttingen, Germany
| | - Yen-Yun Lu
- Abteilung Für Molekulare Genetik, Institut Für Mikrobiologie Und Genetik, Göttinger Zentrum Für Molekulare Biowissenschaften (GZMB), Georg-August Universität Göttingen, Göttingen, Germany
| | - Ivo Coban
- Abteilung Für Molekulare Genetik, Institut Für Mikrobiologie Und Genetik, Göttinger Zentrum Für Molekulare Biowissenschaften (GZMB), Georg-August Universität Göttingen, Göttingen, Germany
| | - Bettina Neumann
- Abteilung Für Molekulare Genetik, Institut Für Mikrobiologie Und Genetik, Göttinger Zentrum Für Molekulare Biowissenschaften (GZMB), Georg-August Universität Göttingen, Göttingen, Germany
| | - Heike Krebber
- Abteilung Für Molekulare Genetik, Institut Für Mikrobiologie Und Genetik, Göttinger Zentrum Für Molekulare Biowissenschaften (GZMB), Georg-August Universität Göttingen, Göttingen, Germany
| |
Collapse
|
27
|
Loss of the fragile X syndrome protein FMRP results in misregulation of nonsense-mediated mRNA decay. Nat Cell Biol 2021; 23:40-48. [PMID: 33420492 PMCID: PMC8273690 DOI: 10.1038/s41556-020-00618-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 11/29/2020] [Indexed: 01/28/2023]
Abstract
Loss of the fragile X protein FMRP is a leading cause of intellectual disability and autism1,2, but the underlying mechanism remains poorly understood. We report that FMRP deficiency results in hyperactivated nonsense-mediated mRNA decay (NMD)3,4 in human SH-SY5Y neuroblastoma cells and fragile X syndrome (FXS) fibroblast-derived induced pluripotent stem cells (iPSCs). We examined the underlying mechanism and found that the key NMD factor UPF1 binds directly to FMRP, promoting FMRP binding to NMD targets. Our data indicate that FMRP acts as an NMD repressor. In the absence of FMRP, NMD targets are relieved from FMRP-mediated translational repression so that their half-lives are decreased and, for those NMD targets encoding NMD factors, increased translation produces abnormally high factor levels despite their hyperactivated NMD. Transcriptome-wide alterations caused by NMD hyperactivation have a role in the FXS phenotype. Consistent with this, small-molecule-mediated inhibition of hyperactivated NMD, which typifies iPSCs derived from patients with FXS, restores a number of neurodifferentiation markers, including those not deriving from NMD targets. Our mechanistic studies reveal that many molecular abnormalities in FMRP-deficient cells are attributable-either directly or indirectly-to misregulated NMD.
Collapse
|
28
|
UPF2 leads to degradation of dendritically targeted mRNAs to regulate synaptic plasticity and cognitive function. Mol Psychiatry 2020; 25:3360-3379. [PMID: 31636381 PMCID: PMC7566522 DOI: 10.1038/s41380-019-0547-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 08/13/2019] [Accepted: 08/19/2019] [Indexed: 12/21/2022]
Abstract
Synaptic plasticity requires a tight control of mRNA levels in dendrites. RNA translation and degradation pathways have been recently linked to neurodevelopmental and neuropsychiatric diseases, suggesting a role for RNA regulation in synaptic plasticity and cognition. While the local translation of specific mRNAs has been implicated in synaptic plasticity, the tightly controlled mechanisms that regulate local quantity of specific mRNAs remain poorly understood. Despite being the only RNA regulatory pathway that is associated with multiple mental illnesses, the nonsense-mediated mRNA decay (NMD) pathway presents an unexplored regulatory mechanism for synaptic function and plasticity. Here, we show that neuron-specific disruption of UPF2, an NMD component, in adulthood attenuates learning, memory, spine density, synaptic plasticity (L-LTP), and potentiates perseverative/repetitive behavior in mice. We report that the NMD pathway operates within dendrites to regulate Glutamate Receptor 1 (GLUR1) surface levels. Specifically, UPF2 modulates the internalization of GLUR1 and promotes its local synthesis in dendrites. We identified neuronal Prkag3 mRNA as a mechanistic substrate for NMD that contributes to the UPF2-mediated regulation of GLUR1 by limiting total GLUR1 levels. These data establish that UPF2 regulates synaptic plasticity, cognition, and local protein synthesis in dendrites, providing fundamental insight into the neuron-specific function of NMD within the brain.
Collapse
|
29
|
Deka B, Chandra P, Singh KK. Functional roles of human Up-frameshift suppressor 3 (UPF3) proteins: From nonsense-mediated mRNA decay to neurodevelopmental disorders. Biochimie 2020; 180:10-22. [PMID: 33132159 DOI: 10.1016/j.biochi.2020.10.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 10/03/2020] [Accepted: 10/22/2020] [Indexed: 12/26/2022]
Abstract
Nonsense-mediated mRNA decay (NMD) is a post-transcriptional quality control mechanism that eradicates aberrant transcripts from cells. Aberrant transcripts are recognized by translating ribosomes, eRFs, and trans-acting NMD factors leading to their degradation. The trans-factors are conserved among eukaryotes and consist of UPF1, UPF2, and UPF3 proteins. Intriguingly, in humans, UPF3 exists as paralog proteins, UPF3A, and UPF3B. While UPF3 paralogs are traditionally known to be involved in the NMD pathway, there is a growing consensus that there are other critical cellular functions beyond quality control that are dictated by the UPF3 proteins. This review presents the current knowledge on the biochemical functions of UPF3 paralogs in diverse cellular processes, including NMD, translation, and genetic compensation response. We also discuss the contribution of the UPF3 paralogs in development and function of the central nervous system and germ cells. Furthermore, significant advances in the past decade have provided new perspectives on the implications of UPF3 paralogs in neurodevelopmental diseases. In this regard, genome- and transcriptome-wide sequencing analysis of patient samples revealed that loss of UPF3B is associated with brain disorders such as intellectual disability, autism, attention deficit hyperactivity disorder, and schizophrenia. Therefore, we further aim to provide an insight into the brain diseases associated with loss-of-function mutations of UPF3B.
Collapse
Affiliation(s)
- Bhagyashree Deka
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
| | - Pratap Chandra
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
| | - Kusum Kumari Singh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
| |
Collapse
|
30
|
The Branched Nature of the Nonsense-Mediated mRNA Decay Pathway. Trends Genet 2020; 37:143-159. [PMID: 33008628 DOI: 10.1016/j.tig.2020.08.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/11/2020] [Accepted: 08/18/2020] [Indexed: 12/16/2022]
Abstract
Nonsense-mediated mRNA decay (NMD) is a conserved translation-coupled quality control mechanism in all eukaryotes that regulates the expression of a significant fraction of both the aberrant and normal transcriptomes. In vertebrates, NMD has become an essential process owing to expansion of the diversity of NMD-regulated transcripts, particularly during various developmental processes. Surprisingly, however, some core NMD factors that are essential for NMD in simpler organisms appear to be dispensable for vertebrate NMD. At the same time, numerous NMD enhancers and suppressors have been identified in multicellular organisms including vertebrates. Collectively, the available data suggest that vertebrate NMD is a complex, branched pathway wherein individual branches regulate specific mRNA subsets to fulfill distinct physiological functions.
Collapse
|
31
|
Domingo D, Nawaz U, Corbett M, Espinoza JL, Tatton-Brown K, Coman D, Wilkinson MF, Gecz J, Jolly LA. A synonymous UPF3B variant causing a speech disorder implicates NMD as a regulator of neurodevelopmental disorder gene networks. Hum Mol Genet 2020; 29:2568-2578. [PMID: 32667670 PMCID: PMC10893962 DOI: 10.1093/hmg/ddaa151] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/22/2020] [Accepted: 07/11/2020] [Indexed: 11/12/2022] Open
Abstract
Loss-of-function mutations of the X-chromosome gene UPF3B cause male neurodevelopmental disorders (NDDs) via largely unknown mechanisms. We investigated initially by interrogating a novel synonymous UPF3B variant in a male with absent speech. In silico and functional studies using cell lines derived from this individual show altered UPF3B RNA splicing. The resulting mRNA species encodes a frame-shifted protein with a premature termination codon (PTC) predicted to elicit degradation via nonsense-mediated mRNA decay (NMD). UPF3B mRNA was reduced in the cell line, and no UPF3B protein was produced, confirming a loss-of-function allele. UPF3B is itself involved in the NMD mechanism which degrades both PTC-bearing mutant transcripts and also many physiological transcripts. RNAseq analysis showed that ~1.6% of mRNAs exhibited altered expression. These mRNA changes overlapped and correlated with those we identified in additional cell lines obtained from individuals harbouring other UPF3B mutations, permitting us to interrogate pathogenic mechanisms of UPF3B-associated NDDs. We identified 102 genes consistently deregulated across all UPF3B mutant cell lines. Of the 51 upregulated genes, 75% contained an NMD-targeting feature, thus identifying high-confidence direct NMD targets. Intriguingly, 22 of the dysregulated genes encoded known NDD genes, suggesting UPF3B-dependent NMD regulates gene networks critical for cognition and behaviour. Indeed, we show that 78.5% of all NDD genes encode a transcript predicted to be targeted by NMD. These data describe the first synonymous UPF3B mutation in a patient with prominent speech and language disabilities and identify plausible mechanisms of pathology downstream of UPF3B mutations involving the deregulation of NDD-gene networks.
Collapse
Affiliation(s)
- Deepti Domingo
- University of Adelaide and Robinson Research Institute, Adelaide, SA 5005, Australia
| | - Urwah Nawaz
- University of Adelaide and Robinson Research Institute, Adelaide, SA 5005, Australia
| | - Mark Corbett
- University of Adelaide and Robinson Research Institute, Adelaide, SA 5005, Australia
| | | | - Katrina Tatton-Brown
- St George’s University of London, London SW17, UK
- Southwest Thames Regional Genetics Centre, St George’s Healthcare NHS Trust, London SW17, UK
| | - David Coman
- School of Medicine, University of Queensland, Brisbane, QLD 4072, Australia
| | - Miles F Wilkinson
- Department of Reproductive Medicine, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jozef Gecz
- University of Adelaide and Robinson Research Institute, Adelaide, SA 5005, Australia
- South Australian Health and Medical Research Institute, Adelaide, SA 5000, Australia
| | - Lachlan A Jolly
- University of Adelaide and Robinson Research Institute, Adelaide, SA 5005, Australia
| |
Collapse
|
32
|
Tan K, Jones SH, Lake BB, Chousal JN, Shum EY, Zhang L, Chen S, Sohni A, Pandya S, Gallo RL, Zhang K, Cook-Andersen H, Wilkinson MF. The role of the NMD factor UPF3B in olfactory sensory neurons. eLife 2020; 9:e57525. [PMID: 32773035 PMCID: PMC7452722 DOI: 10.7554/elife.57525] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 08/09/2020] [Indexed: 12/13/2022] Open
Abstract
The UPF3B-dependent branch of the nonsense-mediated RNA decay (NMD) pathway is critical for human cognition. Here, we examined the role of UPF3B in the olfactory system. Single-cell RNA-sequencing (scRNA-seq) analysis demonstrated considerable heterogeneity of olfactory sensory neuron (OSN) cell populations in wild-type (WT) mice, and revealed that UPF3B loss influences specific subsets of these cell populations. UPF3B also regulates the expression of a large cadre of antimicrobial genes in OSNs, and promotes the selection of specific olfactory receptor (Olfr) genes for expression in mature OSNs (mOSNs). RNA-seq and Ribotag analyses identified classes of mRNAs expressed and translated at different levels in WT and Upf3b-null mOSNs. Integrating multiple computational approaches, UPF3B-dependent NMD target transcripts that are candidates to mediate the functions of NMD in mOSNs were identified in vivo. Together, our data provides a valuable resource for the olfactory field and insights into the roles of NMD in vivo.
Collapse
Affiliation(s)
- Kun Tan
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Samantha H Jones
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Blue B Lake
- Department of Bioengineering, University of California, San DiegoSan DiegoUnited States
| | - Jennifer N Chousal
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Eleen Y Shum
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Lingjuan Zhang
- Department of Dermatology, University of California, San DiegoSan DiegoUnited States
| | - Song Chen
- Department of Bioengineering, University of California, San DiegoSan DiegoUnited States
| | - Abhishek Sohni
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Shivam Pandya
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
| | - Richard L Gallo
- Department of Dermatology, University of California, San DiegoSan DiegoUnited States
| | - Kun Zhang
- Department of Bioengineering, University of California, San DiegoSan DiegoUnited States
| | - Heidi Cook-Andersen
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
- Division of Biological Sciences, University of California, San DiegoSan DiegoUnited States
| | - Miles F Wilkinson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine University of California, San DiegoSan DiegoUnited States
- Institute of Genomic Medicine, University of California, San DiegoSan DiegoUnited States
| |
Collapse
|
33
|
Lavysh D, Neu-Yilik G. UPF1-Mediated RNA Decay-Danse Macabre in a Cloud. Biomolecules 2020; 10:E999. [PMID: 32635561 PMCID: PMC7407380 DOI: 10.3390/biom10070999] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/18/2020] [Accepted: 06/29/2020] [Indexed: 12/21/2022] Open
Abstract
Nonsense-mediated RNA decay (NMD) is the prototype example of a whole family of RNA decay pathways that unfold around a common central effector protein called UPF1. While NMD in yeast appears to be a linear pathway, NMD in higher eukaryotes is a multifaceted phenomenon with high variability with respect to substrate RNAs, degradation efficiency, effector proteins and decay-triggering RNA features. Despite increasing knowledge of the mechanistic details, it seems ever more difficult to define NMD and to clearly distinguish it from a growing list of other UPF1-mediated RNA decay pathways (UMDs). With a focus on mammalian, we here critically examine the prevailing NMD models and the gaps and inconsistencies in these models. By exploring the minimal requirements for NMD and other UMDs, we try to elucidate whether they are separate and definable pathways, or rather variations of the same phenomenon. Finally, we suggest that the operating principle of the UPF1-mediated decay family could be considered similar to that of a computing cloud providing a flexible infrastructure with rapid elasticity and dynamic access according to specific user needs.
Collapse
Affiliation(s)
- Daria Lavysh
- Department of Pediatric Oncology, Hematology and Immunology, University of Heidelberg, Im Neuenheimer Feld 430, 69120 Heidelberg, Germany;
- Molecular Medicine Partnership Unit, University of Heidelberg and European Molecular Biology Laboratory, Im Neuenheimer Feld 350, 69120 Heidelberg, Germany
- Department Clinical Pediatric Oncology, Hopp Kindertumorzentrum am NCT Heidelberg, 69120 Heidelberg, Germany
| | - Gabriele Neu-Yilik
- Department of Pediatric Oncology, Hematology and Immunology, University of Heidelberg, Im Neuenheimer Feld 430, 69120 Heidelberg, Germany;
- Molecular Medicine Partnership Unit, University of Heidelberg and European Molecular Biology Laboratory, Im Neuenheimer Feld 350, 69120 Heidelberg, Germany
- Department Clinical Pediatric Oncology, Hopp Kindertumorzentrum am NCT Heidelberg, 69120 Heidelberg, Germany
| |
Collapse
|
34
|
The RNA quality control pathway nonsense-mediated mRNA decay targets cellular and viral RNAs to restrict KSHV. Nat Commun 2020; 11:3345. [PMID: 32620802 PMCID: PMC7334219 DOI: 10.1038/s41467-020-17151-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 06/11/2020] [Indexed: 12/26/2022] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is an evolutionarily conserved RNA decay mechanism that has emerged as a potent cell-intrinsic restriction mechanism of retroviruses and positive-strand RNA viruses. However, whether NMD is capable of restricting DNA viruses is not known. The DNA virus Kaposi’s sarcoma-associated herpesvirus (KSHV) is the etiological agent of Kaposi’s sarcoma and primary effusion lymphoma (PEL). Here, we demonstrate that NMD restricts KSHV lytic reactivation. Leveraging high-throughput transcriptomics we identify NMD targets transcriptome-wide in PEL cells and identify host and viral RNAs as substrates. Moreover, we identified an NMD-regulated link between activation of the unfolded protein response and transcriptional activation of the main KSHV transcription factor RTA, itself an NMD target. Collectively, our study describes an intricate relationship between cellular targets of an RNA quality control pathway and KSHV lytic gene expression, and demonstrates that NMD can function as a cell intrinsic restriction mechanism acting upon DNA viruses. Cellular nonsense-mediated mRNA decay (NMD) has been shown to play a role in defense against RNA viruses. Here, Zhao et al. show that NMD restricts the DNA virus Kaposi sarcoma-associated herpesvirus (KSHV) via targeting both cellular and viral transcripts leading to inhibition of KSHV lytic reactivation.
Collapse
|
35
|
Lemire G, MacDonald SK, Boycott KM. SMG9-deficiency syndrome caused by a homozygous missense variant: Expanding the genotypic and phenotypic spectrum of this developmental disorder. Am J Med Genet A 2020; 182:1829-1831. [PMID: 32412169 DOI: 10.1002/ajmg.a.61616] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 01/01/2023]
Affiliation(s)
- Gabrielle Lemire
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Stella K MacDonald
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Kym M Boycott
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada.,Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| |
Collapse
|
36
|
eIF4A3 Phosphorylation by CDKs Affects NMD during the Cell Cycle. Cell Rep 2020; 26:2126-2139.e9. [PMID: 30784594 DOI: 10.1016/j.celrep.2019.01.101] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/16/2018] [Accepted: 01/25/2019] [Indexed: 12/24/2022] Open
Abstract
Exon junction complexes (EJCs) loaded onto spliced mRNAs during splicing serve as molecular markers for various post-transcriptional gene-regulatory processes, including nonsense-mediated mRNA decay (NMD). Although the composition and structure of EJCs are well characterized, the mechanism regulating EJC deposition remains unknown. Here we find that threonine 163 (T163) within the RNA-binding motif of eIF4A3 (a core EJC component) is phosphorylated by cyclin-dependent protein kinases 1 and 2 in a cell cycle-dependent manner. T163 phosphorylation hinders binding of eIF4A3 to spliced mRNAs and other EJC components. Instead, it promotes association of eIF4A3 with CWC22, which guides eIF4A3 to an active spliceosome. These molecular events ensure the fidelity of specific deposition of the EJC ∼20-24 nt upstream of an exon-exon junction. Accordingly, NMD is affected by T163 phosphorylation. Collectively, our data provide evidence that T163 phosphorylation affects EJC formation and, consequently, NMD efficiency in a cell cycle-dependent manner.
Collapse
|
37
|
Cheng Y, Lu Q, Shi N, Zhou Q, Rong J, Li L, Wang L, Liu C. Aberrant expression of the UPF1 RNA surveillance gene disturbs keratinocyte homeostasis by stabilizing AREG. Int J Mol Med 2020; 45:1163-1175. [PMID: 32124941 PMCID: PMC7053862 DOI: 10.3892/ijmm.2020.4487] [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: 06/14/2019] [Accepted: 01/22/2020] [Indexed: 11/23/2022] Open
Abstract
The up‑frameshift suppressor 1 homolog (UPF1) RNA surveillance gene is a core element in the nonsense‑mediated RNA decay (NMD) pathway, which impacts a broad spectrum of biological processes in a cell‑specific manner. In the present study, the contribution of the NMD pathway to psoriasis lesions and its moderating effects on the biological processes of keratinocytes was reported. Sanger sequencing for skin scales from two patients with psoriasis identified two mRNA mutations (c.2935_2936insA and c.2030‑2081del) in the UPF1 gene. The somatic mutants produced truncated UPF1 proteins and perturbed the NMD pathway in cells, leading to the upregulation of NMD substrates. As the most abundant epidermal growth factor receptor ligand in keratinocytes, it was concluded that amphiregulin (AREG) mRNA is a natural NMD substrate, that is dependent on its 3' untranslated region sequence. Perturbed NMD modulated keratinocyte homeostasis in an AREG‑dependent but nonidentical manner, which highlighted the unique characteristics of NMD in keratinocytes. By targeting AREG mRNA post‑transcriptionally, the UPF1‑NMD pathway contributed to an imbalance between proliferation on the one hand, and apoptosis and abnormal differentiation, migration and inflammatory response on the other, in keratinocytes, which indicated a role of the NMD pathway in the full development of keratinocyte‑related morbidity and skin diseases.
Collapse
Affiliation(s)
- Yaojia Cheng
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang 311121
| | - Qiuping Lu
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang 311121
| | - Nannan Shi
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang 311121
| | - Qiongyan Zhou
- Department of Dermatology, Affiliated Hospital, Ningbo University, Ningbo, Zhejiang 315211
| | - Jingjing Rong
- Institute of Zoology, Chinese Academy of Sciences, Beijing 100101
| | - Liyun Li
- Information Centre, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650032, P.R. China
| | - Li Wang
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang 311121
| | - Chen Liu
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang 311121
| |
Collapse
|
38
|
Kurosaki T, Popp MW, Maquat LE. Quality and quantity control of gene expression by nonsense-mediated mRNA decay. Nat Rev Mol Cell Biol 2020; 20:406-420. [PMID: 30992545 DOI: 10.1038/s41580-019-0126-2] [Citation(s) in RCA: 437] [Impact Index Per Article: 109.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nonsense-mediated mRNA decay (NMD) is one of the best characterized and most evolutionarily conserved cellular quality control mechanisms. Although NMD was first found to target one-third of mutated, disease-causing mRNAs, it is now known to also target ~10% of unmutated mammalian mRNAs to facilitate appropriate cellular responses - adaptation, differentiation or death - to environmental changes. Mutations in NMD genes in humans are associated with intellectual disability and cancer. In this Review, we discuss how NMD serves multiple purposes in human cells by degrading both mutated mRNAs to protect the integrity of the transcriptome and normal mRNAs to control the quantities of unmutated transcripts.
Collapse
Affiliation(s)
- Tatsuaki Kurosaki
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA.,Center for RNA Biology, University of Rochester, Rochester, NY, USA
| | - Maximilian W Popp
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA.,Center for RNA Biology, University of Rochester, Rochester, NY, USA
| | - Lynne E Maquat
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA. .,Center for RNA Biology, University of Rochester, Rochester, NY, USA.
| |
Collapse
|
39
|
Nagarajan VK, Kukulich PM, von Hagel B, Green PJ. RNA degradomes reveal substrates and importance for dark and nitrogen stress responses of Arabidopsis XRN4. Nucleic Acids Res 2019; 47:9216-9230. [PMID: 31428786 PMCID: PMC6755094 DOI: 10.1093/nar/gkz712] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 07/26/2019] [Accepted: 08/13/2019] [Indexed: 12/12/2022] Open
Abstract
XRN4, the plant cytoplasmic homolog of yeast and metazoan XRN1, catalyzes exoribonucleolytic degradation of uncapped mRNAs from the 5' end. Most studies of cytoplasmic XRN substrates have focused on polyadenylated transcripts, although many substrates are likely first deadenylated. Here, we report the global investigation of XRN4 substrates in both polyadenylated and nonpolyadenylated RNA to better understand the impact of the enzyme in Arabidopsis. RNA degradome analysis demonstrated that xrn4 mutants overaccumulate many more decapped deadenylated intermediates than those that are polyadenylated. Among these XRN4 substrates that have 5' ends precisely at cap sites, those associated with photosynthesis, nitrogen responses and auxin responses were enriched. Moreover, xrn4 was found to be defective in the dark stress response and lateral root growth during N resupply, demonstrating that XRN4 is required during both processes. XRN4 also contributes to nonsense-mediated decay (NMD) and xrn4 accumulates 3' fragments of select NMD targets, despite the lack of the metazoan endoribonuclease SMG6 in plants. Beyond demonstrating that XRN4 is a major player in multiple decay pathways, this study identified intriguing molecular impacts of the enzyme, including those that led to new insights about mRNA decay and discovery of functional contributions at the whole-plant level.
Collapse
Affiliation(s)
- Vinay K Nagarajan
- Delaware Biotechnology Institute and Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19711, USA
| | - Patrick M Kukulich
- Delaware Biotechnology Institute and Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19711, USA
| | - Bryan von Hagel
- Delaware Biotechnology Institute and Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19711, USA
| | - Pamela J Green
- Delaware Biotechnology Institute and Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19711, USA
| |
Collapse
|
40
|
Aznarez I, Nomakuchi TT, Tetenbaum-Novatt J, Rahman MA, Fregoso O, Rees H, Krainer AR. Mechanism of Nonsense-Mediated mRNA Decay Stimulation by Splicing Factor SRSF1. Cell Rep 2019; 23:2186-2198. [PMID: 29768215 PMCID: PMC5999336 DOI: 10.1016/j.celrep.2018.04.039] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 02/20/2018] [Accepted: 04/06/2018] [Indexed: 11/25/2022] Open
Abstract
The splicing factor SRSF1 promotes nonsense-mediated mRNA decay (NMD), a quality control mechanism that degrades mRNAs with premature termination codons (PTCs). Here we show that transcript-bound SRSF1 increases the binding of NMD factor UPF1 to mRNAs while in, or associated with, the nucleus, bypassing UPF2 recruitment and promoting NMD. SRSF1 promotes NMD when positioned downstream of a PTC, which resembles the mode of action of exon junction complex (EJC) and NMD factors. Moreover, splicing and/or EJC deposition increase the effect of SRSF1 on NMD. Lastly, SRSF1 enhances NMD of PTC-containing endogenous transcripts that result from various events. Our findings reveal an alternative mechanism for UPF1 recruitment, uncovering an additional connection between splicing and NMD. SRSF1’s role in the mRNA’s journey from splicing to decay has broad implications for gene expression regulation and genetic diseases.
Collapse
Affiliation(s)
- Isabel Aznarez
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | | | | | | | - Oliver Fregoso
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Holly Rees
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Adrian R Krainer
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
| |
Collapse
|
41
|
Sperling R. Small non-coding RNA within the endogenous spliceosome and alternative splicing regulation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:194406. [PMID: 31323432 DOI: 10.1016/j.bbagrm.2019.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 07/08/2019] [Accepted: 07/09/2019] [Indexed: 10/26/2022]
Abstract
Splicing and alternative splicing (AS), which occur in the endogenous spliceosome, play major roles in regulating gene expression, and defects in them are involved in numerous human diseases including cancer. Although the mechanism of the splicing reaction is well understood, the regulation of AS remains to be elucidated. A group of essential regulatory factors in gene expression are small non-coding RNAs (sncRNA): e.g. microRNA, mainly known for their inhibitory role in translation in the cytoplasm; and small nucleolar RNA, known for their role in methylating non-coding RNA in the nucleolus. Here I highlight a new aspect of sncRNAs found within the endogenous spliceosome. Assembled in non-canonical complexes and through different base pairing than their canonical ones, spliceosomal sncRNAs can potentially target different RNAs. Examples of spliceosomal sncRNAs regulating AS, regulating gene expression, and acting in a quality control of AS are reviewed, suggesting novel functions for spliceosomal sncRNAs. This article is part of a Special Issue entitled: RNA structure and splicing regulation edited by Francisco Baralle, Ravindra Singh and Stefan Stamm.
Collapse
Affiliation(s)
- Ruth Sperling
- Department of Genetics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| |
Collapse
|
42
|
Kishor A, Fritz SE, Hogg JR. Nonsense-mediated mRNA decay: The challenge of telling right from wrong in a complex transcriptome. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 10:e1548. [PMID: 31131562 DOI: 10.1002/wrna.1548] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/01/2019] [Accepted: 05/07/2019] [Indexed: 12/18/2022]
Abstract
The nonsense-mediated mRNA decay pathway selects and degrades its targets using a dense network of RNA-protein and protein-protein interactions. Together, these interactions allow the pathway to collect copious information about the translating mRNA, including translation termination status, splice junction positions, mRNP composition, and 3'UTR length and structure. The core NMD machinery, centered on the RNA helicase UPF1, integrates this information to determine the efficiency of decay. A picture of NMD is emerging in which many factors contribute to the dynamics of decay complex assembly and disassembly, thereby influencing the probability of decay. The ability of the NMD pathway to recognize mRNP features of diverse potential substrates allows it to simultaneously perform quality control and regulatory functions. In vertebrates, increased transcriptome complexity requires balance between these two functions since high NMD efficiency is desirable for maintenance of quality control fidelity but may impair expression of normal mRNAs. NMD has adapted to this challenge by employing mechanisms to enhance identification of certain potential substrates, while using sequence-specific RNA-binding proteins to shield others from detection. These elaborations on the conserved NMD mechanism permit more sensitive post-transcriptional gene regulation but can have severe deleterious consequences, including the failure to degrade pathogenic aberrant mRNAs in many B cell lymphomas. This article is categorized under: RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms.
Collapse
Affiliation(s)
- Aparna Kishor
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Sarah E Fritz
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - J Robert Hogg
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
43
|
Huang L, Aghajan M, Quesenberry T, Low A, Murray SF, Monia BP, Guo S. Targeting Translation Termination Machinery with Antisense Oligonucleotides for Diseases Caused by Nonsense Mutations. Nucleic Acid Ther 2019; 29:175-186. [PMID: 31070517 PMCID: PMC6686700 DOI: 10.1089/nat.2019.0779] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Efforts to develop treatments for diseases caused by nonsense mutations have focused on identification of small molecules that promote translational read-through of messenger RNAs (mRNAs) harboring nonsense stop codons to produce full-length proteins. However, to date, no small molecule read-through drug has received FDA approval, probably because of a lack of balance between efficacy and safety. Depletion of translation termination factors eukaryotic release factor (eRF) 1 and eRF3a in cells was shown to promote translational read-through of a luciferase reporter gene harboring a nonsense mutation. In this study, we identified antisense oligonucleotides (ASOs) targeting translation termination factors and determined if ASO-mediated depletion of these factors could be a potentially effective and safe therapeutic approach for diseases caused by nonsense mutations. We found that ASO-mediated reduction of either eRF1 or eRF3a to 30%–40% of normal levels in the mouse liver is well tolerated. Hemophilia mice that express a mutant allele of human coagulation factor IX (FIX) containing nonsense mutation R338X were treated with eRF1- or eRF3a-ASO. We found that although eRF1- or eRF3a-ASO alone only elicited a moderate read-through effect on hFIX-R338X mRNA, both worked in synergy with geneticin, a small molecule read-through drug, demonstrating significantly increased production of functional full-length hFIX protein to levels that would rescue disease phenotypes in these mice. Overall our results indicate that modulating the translation termination pathway in the liver by ASOs may provide a novel approach to improving the efficacy of small molecule read-through drugs to treat human genetic diseases caused by nonsense mutations.
Collapse
Affiliation(s)
- Lulu Huang
- Ionis Pharmaceuticals, Carlsbad, California
| | | | | | - Audrey Low
- Ionis Pharmaceuticals, Carlsbad, California
| | | | | | | |
Collapse
|
44
|
Ri H, Lee J, Sonn JY, Yoo E, Lim C, Choe J. Drosophila CrebB is a Substrate of the Nonsense-Mediated mRNA Decay Pathway that Sustains Circadian Behaviors. Mol Cells 2019; 42:301-312. [PMID: 31091556 PMCID: PMC6530642 DOI: 10.14348/molcells.2019.2451] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 01/21/2019] [Accepted: 01/21/2019] [Indexed: 12/23/2022] Open
Abstract
Post-transcriptional regulation underlies the circadian control of gene expression and animal behaviors. However, the role of mRNA surveillance via the nonsense-mediated mRNA decay (NMD) pathway in circadian rhythms remains elusive. Here, we report that Drosophila NMD pathway acts in a subset of circadian pacemaker neurons to maintain robust 24 h rhythms of free-running locomotor activity. RNA interference-mediated depletion of key NMD factors in timeless-expressing clock cells decreased the amplitude of circadian locomotor behaviors. Transgenic manipulation of the NMD pathway in clock neurons expressing a neuropeptide PIGMENT-DISPERSING FACTOR (PDF) was sufficient to dampen or lengthen free-running locomotor rhythms. Confocal imaging of a transgenic NMD reporter revealed that arrhythmic Clock mutants exhibited stronger NMD activity in PDF-expressing neurons than wild-type. We further found that hypomorphic mutations in Suppressor with morphogenetic effect on genitalia 5 (Smg5 ) or Smg6 impaired circadian behaviors. These NMD mutants normally developed PDF-expressing clock neurons and displayed daily oscillations in the transcript levels of core clock genes. By contrast, the loss of Smg5 or Smg6 function affected the relative transcript levels of cAMP response element-binding protein B (CrebB ) in an isoform-specific manner. Moreover, the overexpression of a transcriptional repressor form of CrebB rescued free-running locomotor rhythms in Smg5-depleted flies. These data demonstrate that CrebB is a rate-limiting substrate of the genetic NMD pathway important for the behavioral output of circadian clocks in Drosophila.
Collapse
Affiliation(s)
- Hwajung Ri
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| | - Jongbin Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| | - Jun Young Sonn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| | - Eunseok Yoo
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919,
Korea
| | - Chunghun Lim
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919,
Korea
| | - Joonho Choe
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141,
Korea
| |
Collapse
|
45
|
Kim YK, Maquat LE. UPFront and center in RNA decay: UPF1 in nonsense-mediated mRNA decay and beyond. RNA (NEW YORK, N.Y.) 2019; 25:407-422. [PMID: 30655309 PMCID: PMC6426291 DOI: 10.1261/rna.070136.118] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Nonsense-mediated mRNA decay (NMD), which is arguably the best-characterized translation-dependent regulatory pathway in mammals, selectively degrades mRNAs as a means of post-transcriptional gene control. Control can be for the purpose of ensuring the quality of gene expression. Alternatively, control can facilitate the adaptation of cells to changes in their environment. The key to NMD, no matter what its purpose, is the ATP-dependent RNA helicase upstream frameshift 1 (UPF1), without which NMD fails to occur. However, UPF1 does much more than regulate NMD. As examples, UPF1 is engaged in functionally diverse mRNA decay pathways mediated by a variety of RNA-binding proteins that include staufen, stem-loop-binding protein, glucocorticoid receptor, and regnase 1. Moreover, UPF1 promotes tudor-staphylococcal/micrococcal-like nuclease-mediated microRNA decay. In this review, we first focus on how the NMD machinery recognizes an NMD target and triggers mRNA degradation. Next, we compare and contrast the mechanisms by which UPF1 functions in the decay of other mRNAs and also in microRNA decay. UPF1, as a protein polymath, engenders cells with the ability to shape their transcriptome in response to diverse biological and physiological needs.
Collapse
Affiliation(s)
- Yoon Ki Kim
- Creative Research Initiatives Center for Molecular Biology of Translation, Korea University, Seoul 02841, Republic of Korea
- Division of Life Sciences, Korea University, Seoul 02841, Republic of Korea
| | - Lynne E Maquat
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA
- Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
| |
Collapse
|
46
|
Fernandes R, Nogueira G, da Costa PJ, Pinto F, Romão L. Nonsense-Mediated mRNA Decay in Development, Stress and Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1157:41-83. [DOI: 10.1007/978-3-030-19966-1_3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
47
|
Jaffrey SR, Wilkinson MF. Nonsense-mediated RNA decay in the brain: emerging modulator of neural development and disease. Nat Rev Neurosci 2018; 19:715-728. [PMID: 30410025 PMCID: PMC6396682 DOI: 10.1038/s41583-018-0079-z] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Steady-state RNA levels are controlled by the balance between RNA synthesis and RNA turnover. A selective RNA turnover mechanism that has received recent attention in neurons is nonsense-mediated RNA decay (NMD). NMD has been shown to influence neural development, neural stem cell differentiation decisions, axon guidance and synaptic plasticity. In humans, NMD factor gene mutations cause some forms of intellectual disability and are associated with neurodevelopmental disorders, including schizophrenia and autism spectrum disorder. Impairments in NMD are linked to neurodegenerative disorders, including amyotrophic lateral sclerosis. We discuss these findings, their clinical implications and challenges for the future.
Collapse
Affiliation(s)
- Samie R Jaffrey
- Department of Pharmacology, Weill Medical College, Cornell University, New York, NY, USA.
| | - Miles F Wilkinson
- Department of Obstetrics, Gynecology & Reproductive Sciences, University of California, La Jolla, CA, USA.
| |
Collapse
|
48
|
Abstract
Zika virus (ZIKV) is a significant global health threat, as infection has been linked to serious neurological complications, including microcephaly. Using a human stem cell-derived neural progenitor model system, we find that a critical cellular quality control process called the nonsense-mediated mRNA decay (NMD) pathway is disrupted during ZIKV infection. Importantly, disruption of the NMD pathway is a known cause of microcephaly and other neurological disorders. We further identify an interaction between the capsid protein of ZIKV and up-frameshift protein 1 (UPF1), the master regulator of NMD, and show that ZIKV capsid targets UPF1 for degradation. Together, these results offer a new mechanism for how ZIKV infection can cause neuropathology in the developing brain. Zika virus (ZIKV) infection of neural progenitor cells (NPCs) in utero is associated with neurological disorders, such as microcephaly, but a detailed molecular understanding of ZIKV-induced pathogenesis is lacking. Here we show that in vitro ZIKV infection of human cells, including NPCs, causes disruption of the nonsense-mediated mRNA decay (NMD) pathway. NMD is a cellular mRNA surveillance mechanism that is required for normal brain size in mice. Using affinity purification-mass spectrometry, we identified multiple cellular NMD factors that bind to the viral capsid protein, including the central NMD regulator up-frameshift protein 1 (UPF1). Endogenous UPF1 interacted with the ZIKV capsid protein in coimmunoprecipitation experiments, and capsid expression posttranscriptionally downregulated UPF1 protein levels, a process that we confirmed occurs during ZIKV infection. Cellular fractionation studies show that the ZIKV capsid protein specifically targets nuclear UPF1 for degradation via the proteasome. A further decrease in UPF1 levels by RNAi significantly enhanced ZIKV infection in NPC cultures, consistent with a model in which NMD restricts ZIKV infection in the fetal brain. We propose that ZIKV, via the capsid protein, has evolved a strategy to lower UPF1 levels and dampen antiviral activities of NMD, which in turn contributes to neuropathology in vivo.
Collapse
|
49
|
Filatova EN, Utkin OV. The Role of Noncoding mRNA Isoforms in the Regulation of Gene Expression. RUSS J GENET+ 2018. [DOI: 10.1134/s1022795418080057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
50
|
Abstract
Nonsense-mediated mRNA decay is a eukaryotic pathway that degrades transcripts with premature termination codons (PTCs). In most eukaryotes, thousands of transcripts are degraded by NMD, including many important regulators of developmental and stress response pathways. Transcripts can be targeted to NMD by the presence of an upstream ORF or by introduction of a PTC through alternative splicing. Many factors involved in the recognition of PTCs and the destruction of NMD targets have been characterized. While some are highly conserved, others have been repeatedly lost in eukaryotic lineages. Here, I detail the factors involved in NMD, our current understanding of their interactions and how they have evolved. I outline a classification system to describe NMD pathways based on the presence/absence of key NMD factors. These types of NMD pathways exist in multiple different lineages, indicating the plasticity of the NMD pathway through recurrent losses of NMD factors during eukaryotic evolution. By classifying the NMD pathways in this way, gaps in our understanding are revealed, even within well studied organisms. Finally, I discuss the likely driving force behind the origins of the NMD pathway before the appearance of the last eukaryotic common ancestor: transposable element expansion and the consequential origin of introns.
Collapse
Affiliation(s)
- James P B Lloyd
- ARC Centre of Excellence in Plant Energy Biology, University of Western Australia, Perth, Australia
| |
Collapse
|