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Naqvi AS, Corbett RJ, Seghal P, Conkrite KL, Rathi KS, Ennis BM, Hayer KE, Zhang B, Brown MA, Miller DP, Kraya AA, Dybas JM, Geng Z, Blackden C, Arif S, Chroni A, Lahiri A, Hollawell ML, Storm PB, Foster JB, Koptyra M, Madsen PJ, Diskin SJ, Thomas-Tikhonenko A, Resnick AC, Rokita JL. Characterization of aberrant splicing in pediatric central nervous system tumors reveals CLK1 as a candidate oncogenic dependency. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.03.606419. [PMID: 39149264 PMCID: PMC11326178 DOI: 10.1101/2024.08.03.606419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
Pediatric brain cancer is the leading cause of disease-related mortality in children, and many aggressive tumors still lack effective treatment strategies. We characterized aberrant alternative splicing across pediatric brain tumors, identifying pediatric high-grade gliomas (HGGs) among the most heterogeneous. Annotating these events with UniProt, we identified 11,940 splice events in 5,368 genes leading to potential protein function changes. We discovered CDC-like kinase 1 (CLK1) is aberrantly spliced to include exon 4, resulting in a gain of two phosphorylation sites and subsequent activation. Inhibition of CLK1 with Cirtuvivint significantly decreased both cell viability and proliferation in the pediatric HGG KNS-42 cell line. Morpholino-mediated depletion of CLK1 exon 4 splicing reduced RNA expression, protein abundance, and cell viability with concurrent differential expression of 78 cancer genes and differential splicing at functional sites in 193 cancer genes. Our findings highlight a dependency of pediatric HGGs on CLK1 and represent a promising therapeutic strategy.
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Affiliation(s)
- Ammar S. Naqvi
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ryan J. Corbett
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA
| | - Priyanka Seghal
- Division of Cancer Pathobiology, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Karina L. Conkrite
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA
| | - Komal S. Rathi
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Brian M. Ennis
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Katharina E Hayer
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA
- Department of Biomedical and Health Informatics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Bo Zhang
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Miguel A. Brown
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Daniel P. Miller
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Adam A. Kraya
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Joseph M. Dybas
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Zhuangzhuang Geng
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Christopher Blackden
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Shehbeel Arif
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Antonia Chroni
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Aditya Lahiri
- Department of Biomedical and Health Informatics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Madison L. Hollawell
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Phillip B. Storm
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jessica B. Foster
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA
- Department of Pediatrics, University of Pennsylvania, Philadelphia, PA, USA
| | - Mateusz Koptyra
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Peter J. Madsen
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sharon J. Diskin
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA
- Department of Biomedical and Health Informatics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pediatrics, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrei Thomas-Tikhonenko
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA
- Division of Cancer Pathobiology, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pediatrics, University of Pennsylvania, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Adam C. Resnick
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jo Lynne Rokita
- Center for Data-Driven Discovery in Biomedicine, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Neurosurgery, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
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Yustis JC, Devoucoux M, Côté J. The Functional Relationship Between RNA Splicing and the Chromatin Landscape. J Mol Biol 2024; 436:168614. [PMID: 38762032 DOI: 10.1016/j.jmb.2024.168614] [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: 03/04/2024] [Revised: 04/27/2024] [Accepted: 05/13/2024] [Indexed: 05/20/2024]
Abstract
Chromatin is a highly regulated and dynamic structure that has been shown to play an essential role in transcriptional and co-transcriptional regulation. In the context of RNA splicing, early evidence suggested a loose connection between the chromatin landscape and splicing. More recently, it has been shown that splicing occurs in a co-transcriptional manner, meaning that the splicing process occurs in the context of chromatin. Experimental and computational evidence have also shown that chromatin dynamics can influence the splicing process and vice versa. However, much of this evidence provides mainly correlative relationships between chromatin and splicing with just a few concrete examples providing defined molecular mechanisms by which these two processes are functionally related. Nevertheless, it is clear that chromatin and RNA splicing are tightly interconnected to one another. In this review, we highlight the current state of knowledge of the relationship between chromatin and splicing.
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Affiliation(s)
- Juan-Carlos Yustis
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of the CHU de Québec-Université Laval Research Center, Quebec City, Quebec G1R 3S3, Canada
| | - Maëva Devoucoux
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of the CHU de Québec-Université Laval Research Center, Quebec City, Quebec G1R 3S3, Canada
| | - Jacques Côté
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of the CHU de Québec-Université Laval Research Center, Quebec City, Quebec G1R 3S3, Canada.
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Romano R, Bucci C. Antisense therapy: a potential breakthrough in the treatment of neurodegenerative diseases. Neural Regen Res 2024; 19:1027-1035. [PMID: 37862205 PMCID: PMC10749614 DOI: 10.4103/1673-5374.385285] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/13/2023] [Accepted: 07/21/2023] [Indexed: 10/22/2023] Open
Abstract
Neurodegenerative diseases are a group of disorders characterized by the progressive degeneration of neurons in the central or peripheral nervous system. Currently, there is no cure for neurodegenerative diseases and this means a heavy burden for patients and the health system worldwide. Therefore, it is necessary to find new therapeutic approaches, and antisense therapies offer this possibility, having the great advantage of not modifying cellular genome and potentially being safer. Many preclinical and clinical studies aim to test the safety and effectiveness of antisense therapies in the treatment of neurodegenerative diseases. The objective of this review is to summarize the recent advances in the development of these new technologies to treat the most common neurodegenerative diseases, with a focus on those antisense therapies that have already received the approval of the U.S. Food and Drug Administration.
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Affiliation(s)
- Roberta Romano
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Lecce, Italy
| | - Cecilia Bucci
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Lecce, Italy
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4
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Zavileyskiy LG, Pervouchine DD. Post-transcriptional Regulation of Gene Expression via Unproductive Splicing. Acta Naturae 2024; 16:4-13. [PMID: 38698955 PMCID: PMC11062102 DOI: 10.32607/actanaturae.27337] [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: 12/03/2023] [Accepted: 03/01/2024] [Indexed: 05/05/2024] Open
Abstract
Unproductive splicing is a mechanism of post-transcriptional gene expression control in which premature stop codons are inserted into protein-coding transcripts as a result of regulated alternative splicing, leading to their degradation via the nonsense-mediated decay pathway. This mechanism is especially characteristic of RNA-binding proteins, which regulate each other's expression levels and those of other genes in multiple auto- and cross-regulatory loops. Deregulation of unproductive splicing is a cause of serious human diseases, including cancers, and is increasingly being considered as a prominent therapeutic target. This review discusses the types of unproductive splicing events, the mechanisms of auto- and cross-regulation, nonsense-mediated decay escape, and problems in identifying unproductive splice isoforms. It also provides examples of deregulation of unproductive splicing in human diseases and discusses therapeutic strategies for its correction using antisense oligonucleotides and small molecules.
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Affiliation(s)
- L. G. Zavileyskiy
- Lomonosov Moscow State University, Moscow, 119192 Russian Federation
- Skolkovo Institute of Science and Technology, Moscow, 121205 Russian Federation
| | - D. D. Pervouchine
- Skolkovo Institute of Science and Technology, Moscow, 121205 Russian Federation
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5
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Marwan M, Dawood M, Ullah M, Shah IU, Khan N, Hassan MT, Karam M, Rawlins LE, Baple EL, Crosby AH, Saleha S. Unravelling the genetic basis of retinal dystrophies in Pakistani consanguineous families. BMC Ophthalmol 2023; 23:205. [PMID: 37165311 PMCID: PMC10170854 DOI: 10.1186/s12886-023-02948-8] [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: 10/19/2022] [Accepted: 04/26/2023] [Indexed: 05/12/2023] Open
Abstract
BACKGROUND Retinitis Pigmentosa (RP) is a clinically and genetically progressive retinal dystrophy associated with severe visual impairments and sometimes blindness, the most common syndromic form of which is Usher syndrome (USH). This study aimed to further increase understanding of the spectrum of RP in the Khyber Pakhtunkhwa region of Pakistan. METHODOLOGY Four consanguineous families of Pashtun ethnic group were investigated which were referred by the local collaborating ophthalmologists. In total 42 individuals in four families were recruited and investigated using whole exome and dideoxy sequencing. Among them, 20 were affected individuals including 6 in both family 1 and 2, 5 in family 3 and 3 in family 4. RESULT Pathogenic gene variants were identified in all four families, including two in cone dystrophy and RP genes in the same family (PDE6C; c.480delG, p.Asn161ThrfsTer33 and TULP1; c.238 C > T, p.Gln80Ter) with double-homozygous individuals presenting with more severe disease. Other pathogenic variants were identified in MERTK (c.2194C > T, p.Arg732Ter), RHO (c.448G > A, p.Glu150Lys) associated with non-syndromic RP, and MYO7A (c.487G > A, p.Gly163Arg) associated with USH. In addition, the reported variants were of clinical significance as the PDE6C variant was detected novel, whereas TULP1, MERTK, and MYO7A variants were detected rare and first time found segregating with retinal dystrophies in Pakistani consanguineous families. CONCLUSIONS This study increases knowledge of the genetic basis of retinal dystrophies in families from Pakistan providing information important for genetic testing and diagnostic provision particularly from the Khyber Pakhtunkhwa region.
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Affiliation(s)
- Muhammad Marwan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Muhammad Dawood
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Mukhtar Ullah
- Institute of Molecular and Clinical Ophthalmology Basel, Basel, 4031, Switzerland
- Department of Ophthalmology, University of Basel, Basel, 4056, Switzerland
| | - Irfan Ullah Shah
- Department of Ophthalmology, KMU Institute of Medical Sciences KIMS, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Niamat Khan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Muhammad Taimur Hassan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Muhammad Karam
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Lettie E Rawlins
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
- Peninsula Clinical Genetics Service, Royal Devon & Exeter Hospital (Heavitree), Exeter, UK
| | - Emma L Baple
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Andrew H Crosby
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Shamim Saleha
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan.
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Happ HC, Schneider PN, Hong JH, Goes E, Bandouil M, Biar CG, Ramamurthy A, Reese F, Engel K, Weckhuysen S, Scheffer IE, Mefford HC, Calhoun JD, Carvill GL. Long-read sequencing and profiling of RNA-binding proteins reveals the pathogenic mechanism of aberrant splicing of an SCN1A poison exon in epilepsy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.04.538282. [PMID: 37205386 PMCID: PMC10187291 DOI: 10.1101/2023.05.04.538282] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Pathogenic loss-of-function SCN1A variants cause a spectrum of seizure disorders. We previously identified variants in individuals with SCN1A -related epilepsy that fall in or near a poison exon (PE) in SCN1A intron 20 (20N). We hypothesized these variants lead to increased PE inclusion, which introduces a premature stop codon, and, therefore, reduced abundance of the full-length SCN1A transcript and Na v 1.1 protein. We used a splicing reporter assay to interrogate PE inclusion in HEK293T cells. In addition, we used patient-specific induced pluripotent stem cells (iPSCs) differentiated into neurons to quantify 20N inclusion by long and short-read sequencing and Na v 1.1 abundance by western blot. We performed RNA-antisense purification with mass spectrometry to identify RNA-binding proteins (RBPs) that could account for the aberrant PE splicing. We demonstrate that variants in/near 20N lead to increased 20N inclusion by long-read sequencing or splicing reporter assay and decreased Na v 1.1 abundance. We also identified 28 RBPs that differentially interact with variant constructs compared to wild-type, including SRSF1 and HNRNPL. We propose a model whereby 20N variants disrupt RBP binding to splicing enhancers (SRSF1) and suppressors (HNRNPL), to favor PE inclusion. Overall, we demonstrate that SCN1A 20N variants cause haploinsufficiency and SCN1A -related epilepsies. This work provides insights into the complex control of RBP-mediated PE alternative splicing, with broader implications for PE discovery and identification of pathogenic PE variants in other genetic conditions.
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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: 11] [Impact Index Per Article: 11.0] [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.
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Dawood M, Lin S, Din TU, Shah IU, Khan N, Jan A, Marwan M, Sultan K, Nowshid M, Tahir R, Ahmed AN, Yasin M, Baple EL, Crosby AH, Saleha S. Novel mutations in PDE6A and CDHR1 cause retinitis pigmentosa in Pakistani families. Int J Ophthalmol 2021; 14:1843-1851. [PMID: 34926197 PMCID: PMC8640774 DOI: 10.18240/ijo.2021.12.06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 08/11/2021] [Indexed: 11/23/2022] Open
Abstract
AIM To investigate the genetic basis of autosomal recessive retinitis pigmentosa (arRP) in two consanguineous/ endogamous Pakistani families. METHODS Whole exome sequencing (WES) was performed on genomic DNA samples of patients with arRP to identify disease causing mutations. Sanger sequencing was performed to confirm familial segregation of identified mutations, and potential pathogenicity was determined by predictions of the mutations' functions. RESULTS A novel homozygous frameshift mutation [NM_000440.2:c.1054delG, p. (Gln352Argfs*4); Chr5:g.149286886del (GRCh37)] in the PDE6A gene in an endogamous family and a novel homozygous splice site mutation [NM_033100.3:c.1168-1G>A, Chr10:g.85968484G>A (GRCh37)] in the CDHR1 gene in a consanguineous family were identified. The PDE6A variant p. (Gln352Argfs*4) was predicted to be deleterious or pathogenic, whilst the CDHR1 variant c.1168-1G>A was predicted to result in potential alteration of splicing. CONCLUSION This study expands the spectrum of genetic variants for arRP in Pakistani families.
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Affiliation(s)
- Muhammad Dawood
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Siying Lin
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon EX2 5DW, UK
| | - Taj Ud Din
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Irfan Ullah Shah
- Department of Ophthalmology, KMU Institute of Medical Sciences (KIMS) Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Niamat Khan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Abid Jan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Muhammad Marwan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Komal Sultan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Maha Nowshid
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Raheel Tahir
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Asif Naveed Ahmed
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Muhammad Yasin
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
| | - Emma L. Baple
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon EX2 5DW, UK
| | - Andrew H. Crosby
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon EX2 5DW, UK
| | - Shamim Saleha
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat 26000, Khyber Pakhtunkhwa, Pakistan
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Ham KA, Keegan NP, McIntosh CS, Aung-Htut MT, Zaw K, Greer K, Fletcher S, Wilton SD. Induction of cryptic pre-mRNA splice-switching by antisense oligonucleotides. Sci Rep 2021; 11:15137. [PMID: 34302060 PMCID: PMC8302632 DOI: 10.1038/s41598-021-94639-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 07/14/2021] [Indexed: 11/09/2022] Open
Abstract
Antisense oligomers (AOs) are increasingly being used to modulate RNA splicing in live cells, both for research and for the development of therapeutics. While the most common intended effect of these AOs is to induce skipping of whole exons, rare examples are emerging of AOs that induce skipping of only part of an exon, through activation of an internal cryptic splice site. In this report, we examined seven AO-induced cryptic splice sites in six genes. Five of these cryptic splice sites were discovered through our own experiments, and two originated from other published reports. We modelled the predicted effects of AO binding on the secondary structure of each of the RNA targets, and how these alterations would in turn affect the accessibility of the RNA to splice factors. We observed that a common predicted effect of AO binding was disruption of the exon definition signal within the exon's excluded segment.
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Affiliation(s)
- Kristin A Ham
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia.,Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, 6009, Australia
| | - Niall P Keegan
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia.,Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, 6009, Australia
| | - Craig S McIntosh
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia.,Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, 6009, Australia
| | - May T Aung-Htut
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia.,Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, 6009, Australia
| | - Khine Zaw
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia.,Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, 6009, Australia.,Department of Biochemistry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Kane Greer
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia.,Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, 6009, Australia
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia.,Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, 6009, Australia
| | - Steve D Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia. .,Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Perth, WA, 6009, Australia.
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10
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Lim KH, Han Z, Jeon HY, Kach J, Jing E, Weyn-Vanhentenryck S, Downs M, Corrionero A, Oh R, Scharner J, Venkatesh A, Ji S, Liau G, Ticho B, Nash H, Aznarez I. Antisense oligonucleotide modulation of non-productive alternative splicing upregulates gene expression. Nat Commun 2020; 11:3501. [PMID: 32647108 PMCID: PMC7347940 DOI: 10.1038/s41467-020-17093-9] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 06/03/2020] [Indexed: 12/25/2022] Open
Abstract
While most monogenic diseases are caused by loss or reduction of protein function, the need for technologies that can selectively increase levels of protein in native tissues remains. Here we demonstrate that antisense-mediated modulation of pre-mRNA splicing can increase endogenous expression of full-length protein by preventing naturally occurring non-productive alternative splicing and promoting generation of productive mRNA. Bioinformatics analysis of RNA sequencing data identifies non-productive splicing events in 7,757 protein-coding human genes, of which 1,246 are disease-associated. Antisense oligonucleotides targeting multiple types of non-productive splicing events lead to increases in productive mRNA and protein in a dose-dependent manner in vitro. Moreover, intracerebroventricular injection of two antisense oligonucleotides in wild-type mice leads to a dose-dependent increase in productive mRNA and protein in the brain. The targeting of natural non-productive alternative splicing to upregulate expression from wild-type or hypomorphic alleles provides a unique approach to treating genetic diseases. Restoration of normal gene expression is one way to treat monogenic disorders. Here the authors target naturally occurring non-productive alternative splicing using antisense oligonucleotides to promote the production of functional proteins.
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Affiliation(s)
| | - Zhou Han
- Stoke Therapeutics, Inc., Bedford, MA, USA
| | | | - Jacob Kach
- Stoke Therapeutics, Inc., Bedford, MA, USA
| | | | | | | | | | - Raymond Oh
- Stoke Therapeutics, Inc., Bedford, MA, USA
| | | | | | - Sophina Ji
- Stoke Therapeutics, Inc., Bedford, MA, USA
| | - Gene Liau
- Stoke Therapeutics, Inc., Bedford, MA, USA
| | | | - Huw Nash
- Stoke Therapeutics, Inc., Bedford, MA, USA
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11
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Barresi V, Cosentini I, Scuderi C, Napoli S, Di Bella V, Spampinato G, Condorelli DF. Fusion Transcripts of Adjacent Genes: New Insights into the World of Human Complex Transcripts in Cancer. Int J Mol Sci 2019; 20:ijms20215252. [PMID: 31652751 PMCID: PMC6862657 DOI: 10.3390/ijms20215252] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/18/2019] [Accepted: 10/20/2019] [Indexed: 12/12/2022] Open
Abstract
The awareness of genome complexity brought a radical approach to the study of transcriptome, opening eyes to single RNAs generated from two or more adjacent genes according to the present consensus. This kind of transcript was thought to originate only from chromosomal rearrangements, but the discovery of readthrough transcription opens the doors to a new world of fusion RNAs. In the last years many possible intergenic cis-splicing mechanisms have been proposed, unveiling the origins of transcripts that contain some exons of both the upstream and downstream genes. In some cases, alternative mechanisms, such as trans-splicing and transcriptional slippage, have been proposed. Five databases, containing validated and predicted Fusion Transcripts of Adjacent Genes (FuTAGs), are available for the scientific community. A comparative analysis revealed that two of them contain the majority of the results. A complete analysis of the more widely characterized FuTAGs is provided in this review, including their expression pattern in normal tissues and in cancer. Gene structure, intergenic splicing patterns and exon junction sequences have been determined and here reported for well-characterized FuTAGs. The available functional data and the possible roles in cancer progression are discussed.
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Affiliation(s)
- Vincenza Barresi
- Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, 95123 Catania, Italy.
| | - Ilaria Cosentini
- Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, 95123 Catania, Italy.
| | - Chiara Scuderi
- Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, 95123 Catania, Italy.
| | - Salvatore Napoli
- Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, 95123 Catania, Italy.
| | - Virginia Di Bella
- Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, 95123 Catania, Italy.
| | - Giorgia Spampinato
- Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, 95123 Catania, Italy.
| | - Daniele Filippo Condorelli
- Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, 95123 Catania, Italy.
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12
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Hansen MMK, Weinberger LS. Post-Transcriptional Noise Control. Bioessays 2019; 41:e1900044. [PMID: 31222776 PMCID: PMC6637019 DOI: 10.1002/bies.201900044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 04/22/2019] [Indexed: 01/01/2023]
Abstract
Recent evidence indicates that transcriptional bursts are intrinsically amplified by messenger RNA cytoplasmic processing to generate large stochastic fluctuations in protein levels. These fluctuations can be exploited by cells to enable probabilistic bet-hedging decisions. But large fluctuations in gene expression can also destabilize cell-fate commitment. Thus, it is unclear if cells temporally switch from high to low noise, and what mechanisms enable this switch. Here, the discovery of a post-transcriptional mechanism that attenuates noise in HIV is reviewed. Early in its life cycle, HIV amplifies transcriptional fluctuations to probabilistically select alternate fates, whereas at late times, HIV utilizes a post-transcriptional feedback mechanism to commit to a specific fate. Reanalyzing various reported post-transcriptional negative feedback architectures reveals that they attenuate noise more efficiently than classic transcriptional autorepression, leading to the derivation of an assay to detect post-transcriptional motifs. It is hypothesized that coupling transcriptional and post-transcriptional autoregulation enables efficient temporal noise control to benefit developmental bet-hedging decisions.
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Affiliation(s)
- Maike M. K. Hansen
- Gladstone|UCSF Center for Cell Circuitry, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Leor S. Weinberger
- Gladstone|UCSF Center for Cell Circuitry, Gladstone Institutes, San Francisco, CA 94158, USA
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA
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13
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Transcriptome profiling in Rift Valley fever virus infected cells reveals modified transcriptional and alternative splicing programs. PLoS One 2019; 14:e0217497. [PMID: 31136639 PMCID: PMC6538246 DOI: 10.1371/journal.pone.0217497] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 05/13/2019] [Indexed: 12/27/2022] Open
Abstract
Rift Valley fever virus (RVFV) is a negative-sense RNA virus belonging to the Phenuiviridae family that infects both domestic livestock and humans. The NIAID has designated RVFV as a Category A priority emerging pathogen due to the devastating public health outcomes associated with epidemic outbreaks. However, there is no licensed treatment or vaccine approved for human use. Therefore it is of great interest to understand RVFV pathogenesis in infected hosts in order to facilitate creation of targeted therapies and treatment options. Here we provide insight into the host-pathogen interface in human HEK293 cells during RVFV MP-12 strain infection using high-throughput mRNA sequencing technology. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of differentially expressed genes showed robust innate immune and cytokine-mediated inflammatory pathway activation as well as alterations in pathways associated with fatty acid metabolism and extracellular matrix receptor signaling. We also analyzed the promoter regions of DEGs for patterns in transcription factor binding sites, and found several that are known to act synergistically to impact apoptosis, immunity, metabolism, and cell growth and differentiation. Lastly, we noted dramatic changes in host alternative splicing patterns in genes associated with mRNA decay and surveillance, RNA transport, and DNA repair. This study has improved our understanding of RVFV pathogenesis and has provided novel insight into pathways and signaling modules important for RVFV diagnostics and therapeutic development.
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14
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Insights into Telomerase/hTERT Alternative Splicing Regulation Using Bioinformatics and Network Analysis in Cancer. Cancers (Basel) 2019; 11:cancers11050666. [PMID: 31091669 PMCID: PMC6562651 DOI: 10.3390/cancers11050666] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 01/08/2023] Open
Abstract
The reactivation of telomerase in cancer cells remains incompletely understood. The catalytic component of telomerase, hTERT, is thought to be the limiting component in cancer cells for the formation of active enzymes. hTERT gene expression is regulated at several levels including chromatin, DNA methylation, transcription factors, and RNA processing events. Of these regulatory events, RNA processing has received little attention until recently. RNA processing and alternative splicing regulation have been explored to understand how hTERT is regulated in cancer cells. The cis- and trans-acting factors that regulate the alternative splicing choice of hTERT in the reverse transcriptase domain have been investigated. Further, it was discovered that the splicing factors that promote the production of full-length hTERT were also involved in cancer cell growth and survival. The goals are to review telomerase regulation via alternative splicing and the function of hTERT splicing variants and to point out how bioinformatics approaches are leading the way in elucidating the networks that regulate hTERT splicing choice and ultimately cancer growth.
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15
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Wan Y, Yuan G, He B, Xu B, Xie W, Wang S, Zhang Y, Wu Q, Zhou X. Foccα6, a truncated nAChR subunit, positively correlates with spinosad resistance in the western flower thrips, Frankliniella occidentalis (Pergande). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 99:1-10. [PMID: 29753712 DOI: 10.1016/j.ibmb.2018.05.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/07/2018] [Accepted: 05/07/2018] [Indexed: 06/08/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs), a molecular target for spinosyns and neonicotinoids, mediate rapid cholinergic transmission in insect central nervous system by binding acetylcholine. Previous studies have shown that mutations in nAChRs contribute to the high level of resistance to these two classes of insecticides. In this study, we identified nine nAChR subunits from a transcriptome of the western flower thrips, Frankliniella occidentalis, including α1-7, β1, and β2. Exon 4 of α4 and exons 3 and 8 of α6 each have two splicing variants, respectively. In addition, altered or incorrect splicing leads to truncated forms of α3, α5, and α6 subunits. The abundance of every nAChRs in both spinosad susceptible and resistant strains was highest in the 1st instar nymph. Significantly more truncated forms of α6 subunit were detected in spinosad resistant strains, whereas, hardly any full-length form was found in the two highly resistant F. occidentalis strains (resistance ratio >104-fold). Under laboratory conditions, spinosad resistance was positively correlated with truncated α6 transcripts. The correlation was later confirmed under the field conditions using five field strains. As the molecular target of spinosad, the percentage of truncated nAChR α6 subunits can be used as a diagnostic tool to detect and quantify spinosad resistance in the field.
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Affiliation(s)
- Yanran Wan
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Guangdi Yuan
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Bingqing He
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Baoyun Xu
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Wen Xie
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Shaoli Wang
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Youjun Zhang
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Qingjun Wu
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Xuguo Zhou
- Department of Entomology, University of Kentucky, Lexington, KY, USA.
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16
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Suess B, Kemmerer K, Weigand JE. Splicing and Alternative Splicing Impact on Gene Design. Synth Biol (Oxf) 2018. [DOI: 10.1002/9783527688104.ch7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Beatrix Suess
- Department of Biology; Technische Universität Darmstadt; Schnittspahnstraße 10 64287 Darmstadt Germany
| | - Katrin Kemmerer
- Department of Biology; Technische Universität Darmstadt; Schnittspahnstraße 10 64287 Darmstadt Germany
| | - Julia E. Weigand
- Department of Biology; Technische Universität Darmstadt; Schnittspahnstraße 10 64287 Darmstadt Germany
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17
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Shelby MV. Waardenburg Syndrome Expression and Penetrance. JOURNAL OF RARE DISEASES RESEARCH & TREATMENT 2017; 2:31-40. [PMID: 30854529 PMCID: PMC6404762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Through a combination of in silico research and reviews of previous work, mechanisms by which nonsense-mediated mRNA decay (NMD) affects the inheritance and expressivity of Waardenburg syndrome is realized. While expressivity and inheritance both relate to biochemical processes underlying a gene's function, this research explores how alternative splicing and premature termination codons (PTC's) within mRNAs mutated in the disease are either translated into deleterious proteins or decayed to minimize expression of altered proteins. Elucidation of splice variants coupled with NMD perpetuating the various symptoms and inheritance patterns of this disease represent novel findings. By investigating nonsense mutations that lie within and outside the NMD boundary of these transcripts we can evaluate the effects of protein truncation versus minimized protein expression on the variable expressivity found between Type I and Type III Waardenburg syndrome, PAX3, while comparatively evaluating EDN3 and SOX10's role in inheritance of Type IV subtypes of the disease. This review will demonstrate how alternative splicing perpetuates or limits NMD activity by way of PTC positioning, thereby affecting the presentation of Waardenburg syndrome.
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Affiliation(s)
- Myeshia V. Shelby
- Department of Genetics and Human Genetics, Howard University Graduate School, Howard University, USA
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18
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Reble E, Dineen A, Barr CL. The contribution of alternative splicing to genetic risk for psychiatric disorders. GENES BRAIN AND BEHAVIOR 2017; 17:e12430. [PMID: 29052934 DOI: 10.1111/gbb.12430] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Revised: 09/25/2017] [Accepted: 10/12/2017] [Indexed: 12/12/2022]
Abstract
A genetic contribution to psychiatric disorders has clearly been established and genome-wide association studies now provide the location of risk genes and genetic variants associated with risk. However, the mechanism by which these genes and variants contribute to psychiatric disorders is mostly undetermined. This is in part because non-synonymous protein coding changes cannot explain the majority of variants associated with complex genetic traits. Based on this, it is predicted that these variants are causing gene expression changes, including changes to alternative splicing. Genetic changes influencing alternative splicing have been identified as risk factors in Mendelian disorders; however, currently there is a paucity of research on the role of alternative splicing in complex traits. This stems partly from the difficulty of predicting the role of genetic variation in splicing. Alterations to canonical splice site sequences, nucleotides adjacent to splice junctions, and exonic and intronic splicing regulatory sequences can influence splice site choice. Recent studies have identified global changes in alternatively spliced transcripts in brain tissues, some of which correlate with altered levels of splicing trans factors. Disease-associated variants have also been found to affect cis-acting splicing regulatory sequences and alter the ratio of alternatively spliced transcripts. These findings are reviewed here, as well as the current datasets and resources available to study alternative splicing in psychiatric disorders. Identifying and understanding risk variants that cause alternative splicing is critical to understanding the mechanisms of risk as well as to pave the way for new therapeutic options.
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Affiliation(s)
- E Reble
- Genetics and Development Division, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - A Dineen
- Genetics and Development Division, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - C L Barr
- Genetics and Development Division, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada.,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada
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19
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Jacob AG, Smith CWJ. Intron retention as a component of regulated gene expression programs. Hum Genet 2017; 136:1043-1057. [PMID: 28391524 PMCID: PMC5602073 DOI: 10.1007/s00439-017-1791-x] [Citation(s) in RCA: 190] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 03/29/2017] [Indexed: 12/16/2022]
Abstract
Intron retention has long been an exemplar of regulated splicing with case studies of individual events serving as models that provided key mechanistic insights into the process of splicing control. In organisms such as plants and budding yeast, intron retention is well understood as a major mechanism of gene expression regulation. In contrast, in mammalian systems, the extent and functional significance of intron retention have, until recently, remained greatly underappreciated. Technical challenges to the global detection and quantitation of transcripts with retained introns have often led to intron retention being overlooked or dismissed as “noise”. Now, however, with the wealth of information available from high-throughput deep sequencing, combined with focused computational and statistical analyses, we are able to distinguish clear intron retention patterns in various physiological and pathological contexts. Several recent studies have demonstrated intron retention as a central component of gene expression programs during normal development as well as in response to stress and disease. Furthermore, these studies revealed various ways in which intron retention regulates protein isoform production, RNA stability and translation efficiency, and rapid induction of expression via post-transcriptional splicing of retained introns. In this review, we highlight critical findings from these transcriptomic studies and discuss commonalties in the patterns prevalent in intron retention networks at the functional and regulatory levels.
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Affiliation(s)
- Aishwarya G Jacob
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Christopher W J Smith
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK.
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20
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Fernández-Moya SM, Ehses J, Kiebler MA. The alternative life of RNA-sequencing meets single molecule approaches. FEBS Lett 2017; 591:1455-1470. [PMID: 28369835 DOI: 10.1002/1873-3468.12639] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 03/15/2017] [Accepted: 03/24/2017] [Indexed: 12/31/2022]
Abstract
The central dogma of RNA processing has started to totter. Single genes produce a variety of mRNA isoforms by mRNA modification, alternative polyadenylation (APA), and splicing. Different isoforms, even those that code for the identical protein, may differ in function or spatiotemporal expression. One option of how this can be achieved is by the selective recruitment of trans-acting factors to the 3'-untranslated region of a given isoform. Recent innovations in high-throughput RNA-sequencing methods allow deep insight into global RNA regulation, whereas novel imaging-based technologies enable researchers to explore single RNA molecules during different stages of development, in different tissues and different compartments of the cell. Resolving the dynamic function of ribonucleoprotein particles in splicing, APA, or RNA modification will enable us to understand their contribution to pathological conditions.
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Affiliation(s)
| | - Janina Ehses
- BioMedical Center, Ludwig Maximilians University, Planegg-Martinsried, Germany
| | - Michael A Kiebler
- BioMedical Center, Ludwig Maximilians University, Planegg-Martinsried, Germany
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21
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Hsu MK, Lin HY, Chen FC. NMD Classifier: A reliable and systematic classification tool for nonsense-mediated decay events. PLoS One 2017; 12:e0174798. [PMID: 28369084 PMCID: PMC5378362 DOI: 10.1371/journal.pone.0174798] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 03/15/2017] [Indexed: 01/23/2023] Open
Abstract
Nonsense-mediated decay (NMD) degrades mRNAs that include premature termination codons to avoid the translation and accumulation of truncated proteins. This mechanism has been found to participate in gene regulation and a wide spectrum of biological processes. However, the evolutionary and regulatory origins of NMD-targeted transcripts (NMDTs) have been less studied, partly because of the complexity in analyzing NMD events. Here we report NMD Classifier, a tool for systematic classification of NMD events for either annotated or de novo assembled transcripts. This tool is based on the assumption of minimal evolution/regulation–an event that leads to the least change is the most likely to occur. Our simulation results indicate that NMD Classifier can correctly identify an average of 99.3% of the NMD-causing transcript structural changes, particularly exon inclusions/exclusions and exon boundary alterations. Researchers can apply NMD Classifier to evolutionary and regulatory studies by comparing NMD events of different biological conditions or in different organisms.
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Affiliation(s)
- Min-Kung Hsu
- Department of Biological Science and Technology, National Chiao-Tung University, Hsinchu City, Taiwan
| | - Hsuan-Yu Lin
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan Township, Miaoli County, Taiwan
| | - Feng-Chi Chen
- Department of Biological Science and Technology, National Chiao-Tung University, Hsinchu City, Taiwan
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan Township, Miaoli County, Taiwan
- School of Dentistry, China Medical University, Taichung City, Taiwan
- * E-mail:
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22
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Jin L, Li G, Yu D, Huang W, Cheng C, Liao S, Wu Q, Zhang Y. Transcriptome analysis reveals the complexity of alternative splicing regulation in the fungus Verticillium dahliae. BMC Genomics 2017; 18:130. [PMID: 28166730 PMCID: PMC5294800 DOI: 10.1186/s12864-017-3507-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 01/14/2017] [Indexed: 12/22/2022] Open
Abstract
Background Alternative splicing (AS) regulation is extensive and shapes the functional complexity of higher organisms. However, the contribution of alternative splicing to fungal biology is not well studied. Results This study provides sequences of the transcriptomes of the plant wilt pathogen Verticillium dahliae, using two different strains and multiple methods for cDNA library preparations. We identified alternatively spliced mRNA isoforms in over a half of the multi-exonic fungal genes. Over one-thousand isoforms involve TopHat novel splice junction; multiple types of combinatory alternative splicing patterns were identified. We showed that one Verticillium gene could use four different 5′ splice sites and two different 3′ donor sites to produce up to five mature mRNAs, representing one of the most sophisticated alternative splicing model in eukaryotes other than animals. Hundreds of novel intron types involving a pair of new splice sites were identified in the V. dahliae genome. All the types of AS events were validated by using RT-PCR. Functional enrichment analysis showed that AS genes are involved in most known biological functions and enriched in ATP biosynthesis, sexual/asexual reproduction, morphogenesis, signal transduction etc., predicting that the AS regulation modulates mRNA isoform output and shapes the V. dahliae proteome plasticity of the pathogen in response to the environmental and developmental changes. Conclusions These findings demonstrate the comprehensive alternative splicing mechanisms in a fungal plant pathogen, which argues the importance of this fungus in developing complicate genome regulation strategies in eukaryotes. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3507-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lirong Jin
- Key Laboratory of Integrated Pest Management on Crops in Central China, Institute of Plant Protection and Soil Science, Hubei Academy of Agricultural Sciences, Wuhan, Hubei, 430064, China
| | - Guanglin Li
- Center for Genome Analysis, ABLife Inc., Optics Valley International Biomedical Park, Building 9-4, East Lake High-Tech Development Zone, 388 Gaoxin 2nd Road, Wuhan, Hubei, 430075, China.,College of Life Science, Shaanxi Normal University, Xi'an, Shaanxi, 710119, China
| | - Dazhao Yu
- Key Laboratory of Integrated Pest Management on Crops in Central China, Institute of Plant Protection and Soil Science, Hubei Academy of Agricultural Sciences, Wuhan, Hubei, 430064, China.
| | - Wei Huang
- Key Laboratory of Integrated Pest Management on Crops in Central China, Institute of Plant Protection and Soil Science, Hubei Academy of Agricultural Sciences, Wuhan, Hubei, 430064, China
| | - Chao Cheng
- Center for Genome Analysis, ABLife Inc., Optics Valley International Biomedical Park, Building 9-4, East Lake High-Tech Development Zone, 388 Gaoxin 2nd Road, Wuhan, Hubei, 430075, China
| | - Shengjie Liao
- Center for Genome Analysis, ABLife Inc., Optics Valley International Biomedical Park, Building 9-4, East Lake High-Tech Development Zone, 388 Gaoxin 2nd Road, Wuhan, Hubei, 430075, China.,Laboratory for Genome Regulation and Human Heath, ABLife Inc., Optics Valley International Biomedical Park, Building 9-4, East Lake High-Tech Development Zone, 388 Gaoxin 2nd Road, Wuhan, Hubei, 430075, China
| | - Qijia Wu
- Laboratory for Genome Regulation and Human Heath, ABLife Inc., Optics Valley International Biomedical Park, Building 9-4, East Lake High-Tech Development Zone, 388 Gaoxin 2nd Road, Wuhan, Hubei, 430075, China.,Seqhealth Technology Co., Ltd, Wuhan, Hubei, 430075, China
| | - Yi Zhang
- Center for Genome Analysis, ABLife Inc., Optics Valley International Biomedical Park, Building 9-4, East Lake High-Tech Development Zone, 388 Gaoxin 2nd Road, Wuhan, Hubei, 430075, China. .,Laboratory for Genome Regulation and Human Heath, ABLife Inc., Optics Valley International Biomedical Park, Building 9-4, East Lake High-Tech Development Zone, 388 Gaoxin 2nd Road, Wuhan, Hubei, 430075, China.
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23
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Mooney CM, Jimenez-Mateos EM, Engel T, Mooney C, Diviney M, Venø MT, Kjems J, Farrell MA, O'Brien DF, Delanty N, Henshall DC. RNA sequencing of synaptic and cytoplasmic Upf1-bound transcripts supports contribution of nonsense-mediated decay to epileptogenesis. Sci Rep 2017; 7:41517. [PMID: 28128343 PMCID: PMC5269742 DOI: 10.1038/srep41517] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 12/20/2016] [Indexed: 12/19/2022] Open
Abstract
The nonsense mediated decay (NMD) pathway is a critical surveillance mechanism for identifying aberrant mRNA transcripts. It is unknown, however, whether the NMD system is affected by seizures in vivo and whether changes confer beneficial or maladaptive responses that influence long-term outcomes such the network alterations that produce spontaneous recurrent seizures. Here we explored the responses of the NMD pathway to prolonged seizures (status epilepticus) and investigated the effects of NMD inhibition on epilepsy in mice. Status epilepticus led to increased protein levels of Up-frameshift suppressor 1 homolog (Upf1) within the mouse hippocampus. Upf1 protein levels were also higher in resected hippocampus from patients with intractable temporal lobe epilepsy. Immunoprecipitation of Upf1-bound RNA from the cytoplasmic and synaptosomal compartments followed by RNA sequencing identified unique populations of NMD-associated transcripts and altered levels after status epilepticus, including known substrates such as Arc as well as novel targets including Inhba and Npas4. Finally, long-term video-EEG recordings determined that pharmacologic interference in the NMD pathway after status epilepticus reduced the later occurrence of spontaneous seizures in mice. These findings suggest compartment-specific recruitment and differential loading of transcripts by NMD pathway components may contribute to the process of epileptogenesis.
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Affiliation(s)
- Claire M Mooney
- Department of Physiology &Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Eva M Jimenez-Mateos
- Department of Physiology &Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Tobias Engel
- Department of Physiology &Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Catherine Mooney
- Department of Physiology &Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Mairead Diviney
- Department of Physiology &Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Morten T Venø
- Department of Molecular Biology and Genetics and Center for DNA Nanotechnology and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
| | - Jørgen Kjems
- Department of Molecular Biology and Genetics and Center for DNA Nanotechnology and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
| | | | | | | | - David C Henshall
- Department of Physiology &Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
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24
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Matos ML, Lapyckyj L, Rosso M, Besso MJ, Mencucci MV, Briggiler CIM, Giustina S, Furlong LI, Vazquez-Levin MH. Identification of a Novel Human E-Cadherin Splice Variant and Assessment of Its Effects Upon EMT-Related Events. J Cell Physiol 2016; 232:1368-1386. [PMID: 27682981 DOI: 10.1002/jcp.25622] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 09/27/2016] [Indexed: 12/15/2022]
Abstract
Epithelial Cadherin (E-cadherin) is involved in calcium-dependent cell-cell adhesion and signal transduction. The E-cadherin decrease/loss is a hallmark of Epithelial to Mesenchymal Transition (EMT), a key event in tumor progression. The underlying molecular mechanisms that trigger E-cadherin loss and consequent EMT have not been completely elucidated. This study reports the identification of a novel human E-cadherin variant mRNA produced by alternative splicing. A bioinformatics evaluation of the novel mRNA sequence and biochemical verifications suggest its regulation by Nonsense-Mediated mRNA Decay (NMD). The novel E-cadherin variant was detected in 29/42 (69%) human tumor cell lines, expressed at variable levels (E-cadherin variant expression relative to the wild type mRNA = 0.05-11.6%). Stable transfection of the novel E-cadherin variant in MCF-7 cells (MCF7Ecadvar) resulted in downregulation of wild type E-cadherin expression (transcript/protein) and EMT-related changes, among them acquisition of a fibroblastic-like cell phenotype, increased expression of Twist, Snail, Zeb1, and Slug transcriptional repressors and decreased expression of ESRP1 and ESRP2 RNA binding proteins. Moreover, loss of cytokeratins and gain of vimentin, N-cadherin and Dysadherin/FXYD5 proteins was observed. Dramatic changes in cell behavior were found in MCF7Ecadvar, as judged by the decreased cell-cell adhesion (Hanging-drop assay), increased cell motility (Wound Healing) and increased cell migration (Transwell) and invasion (Transwell w/Matrigel). Some changes were found in MCF-7 cells incubated with culture medium supplemented with conditioned medium from HEK-293 cells transfected with the E-cadherin variant mRNA. Further characterization of the novel E-cadherin variant will help understanding the molecular basis of tumor progression and improve cancer diagnosis. J. Cell. Physiol. 232: 1368-1386, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- María Laura Matos
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
| | - Lara Lapyckyj
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
| | - Marina Rosso
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
| | - María José Besso
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
| | - María Victoria Mencucci
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
| | - Clara Isabel Marín Briggiler
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
| | - Silvina Giustina
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
| | - Laura Inés Furlong
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
| | - Mónica Hebe Vazquez-Levin
- Instituto de Biología y Medicina Experimental (IBYME). National Research Council of Argentina (CONICET). Fundación IBYME, Vuelta de Obligado 2490, Buenos Aires, Argentina
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25
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Cortés-López M, Miura P. Emerging Functions of Circular RNAs. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2016; 89:527-537. [PMID: 28018143 PMCID: PMC5168830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Many thousands of Circular RNAs (circRNAs) have recently been identified in metazoan genomes by transcriptome-wide sequencing. Most circRNAs are generated by back-splicing events from exons of protein-coding genes. A great deal of progress has recently been made in understanding the genome-wide expression patterns, biogenesis, and regulation of circRNAs. To date, however, few functions of circRNAs have been identified. CircRNAs are preferentially expressed in neural tissues and some are found at synapses, suggesting possible functions in the nervous system. Several circRNAs have been shown to function as microRNA "sponges" to counteract microRNA mediated repression of mRNA. New functions for circRNAs are arising, including protein sequestration, transcriptional regulation, and potential functions in cancer. Here, we highlight the recent progress made in understanding the biogenesis and regulation of circRNAs, discuss newly uncovered circRNA functions, and explain the methodological approaches that could reveal more exciting and unexpected roles for these RNAs.
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Affiliation(s)
- Mariela Cortés-López
- Centro de Ciencias Genómicas UNAM Cuernavaca, Morelos, Mexico,University of Nevada, Reno, Department of Biology, Reno, NV, USA
| | - Pedro Miura
- University of Nevada, Reno, Department of Biology, Reno, NV, USA,To whom all correspondence should be addressed: Pedro Miura, 1664 N. Virginia St. Reno, NV, 89557 Phone: 775-682-7004; Fax (775) 784-1302;
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26
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Lin L, Jiang P, Park JW, Wang J, Lu ZX, Lam MPY, Ping P, Xing Y. The contribution of Alu exons to the human proteome. Genome Biol 2016; 17:15. [PMID: 26821878 PMCID: PMC4731929 DOI: 10.1186/s13059-016-0876-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 01/08/2016] [Indexed: 12/19/2022] Open
Abstract
Background Alu elements are major contributors to lineage-specific new exons in primate and human genomes. Recent studies indicate that some Alu exons have high transcript inclusion levels or tissue-specific splicing profiles, and may play important regulatory roles in modulating mRNA degradation or translational efficiency. However, the contribution of Alu exons to the human proteome remains unclear and controversial. The prevailing view is that exons derived from young repetitive elements, such as Alu elements, are restricted to regulatory functions and have not had adequate evolutionary time to be incorporated into stable, functional proteins. Results We adopt a proteotranscriptomics approach to systematically assess the contribution of Alu exons to the human proteome. Using RNA sequencing, ribosome profiling, and proteomics data from human tissues and cell lines, we provide evidence for the translational activities of Alu exons and the presence of Alu exon derived peptides in human proteins. These Alu exon peptides represent species-specific protein differences between primates and other mammals, and in certain instances between humans and closely related primates. In the case of the RNA editing enzyme ADARB1, which contains an Alu exon peptide in its catalytic domain, RNA sequencing analyses of A-to-I editing demonstrate that both the Alu exon skipping and inclusion isoforms encode active enzymes. The Alu exon derived peptide may fine tune the overall editing activity and, in limited cases, the site selectivity of ADARB1 protein products. Conclusions Our data indicate that Alu elements have contributed to the acquisition of novel protein sequences during primate and human evolution. Electronic supplementary material The online version of this article (doi:10.1186/s13059-016-0876-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lan Lin
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
| | - Peng Jiang
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, 53707, USA.
| | - Juw Won Park
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA. .,Department of Computer Engineering and Computer Science, University of Louisville, Louisville, KY, 40292, USA. .,KBRIN Bioinformatics Core, University of Louisville, Louisville, KY, 40202, USA.
| | - Jinkai Wang
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
| | - Zhi-Xiang Lu
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
| | - Maggie P Y Lam
- Department of Physiology, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
| | - Peipei Ping
- Department of Physiology, University of California, Los Angeles, Los Angeles, CA, 90095, USA. .,Department of Medicine, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
| | - Yi Xing
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
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Jo BS, Choi SS. Introns: The Functional Benefits of Introns in Genomes. Genomics Inform 2015; 13:112-8. [PMID: 26865841 PMCID: PMC4742320 DOI: 10.5808/gi.2015.13.4.112] [Citation(s) in RCA: 180] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 12/14/2015] [Accepted: 12/21/2015] [Indexed: 01/12/2023] Open
Abstract
The intron has been a big biological mystery since it was first discovered in several aspects. First, all of the completely sequenced eukaryotes harbor introns in the genomic structure, whereas no prokaryotes identified so far carry introns. Second, the amount of total introns varies in different species. Third, the length and number of introns vary in different genes, even within the same species genome. Fourth, all introns are copied into RNAs by transcription and DNAs by replication processes, but intron sequences do not participate in protein-coding sequences. The existence of introns in the genome should be a burden to some cells, because cells have to consume a great deal of energy to copy and excise them exactly at the correct positions with the help of complicated spliceosomal machineries. The existence throughout the long evolutionary history is explained, only if selective advantages of carrying introns are assumed to be given to cells to overcome the negative effect of introns. In that regard, we summarize previous research about the functional roles or benefits of introns. Additionally, several other studies strongly suggesting that introns should not be junk will be introduced.
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Affiliation(s)
- Bong-Seok Jo
- Department of Medical Biotechnology, College of Biomedical Science, and Institute of Bioscience & Biotechnology, Kangwon National University, Chuncheon 24341, Korea
| | - Sun Shim Choi
- Department of Medical Biotechnology, College of Biomedical Science, and Institute of Bioscience & Biotechnology, Kangwon National University, Chuncheon 24341, Korea
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28
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Bebbere D, Ariu F, Bogliolo L, Masala L, Murrone O, Fattorini M, Falchi L, Ledda S. Expression of maternally derived KHDC3, NLRP5, OOEP and TLE6 is associated with oocyte developmental competence in the ovine species. BMC DEVELOPMENTAL BIOLOGY 2014; 14:40. [PMID: 25420964 PMCID: PMC4247878 DOI: 10.1186/s12861-014-0040-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 11/11/2014] [Indexed: 12/30/2022]
Abstract
BACKGROUND The sub-cortical maternal complex (SCMC), located in the subcortex of mouse oocytes and preimplantation embryos, is composed of at least four proteins encoded by maternal effect genes: OOEP, NLRP5/MATER, TLE6 and KHDC3/FILIA. The SCMC assembles during oocyte growth and was seen to be essential for murine zygote progression beyond the first embryonic cell divisions; although roles in chromatin reprogramming and embryonic genome activation were hypothesized, the full range of functions of the complex in preimplantation development remains largely unknown. RESULTS Here we report the expression of the SCMC genes in ovine oocytes and pre-implantation embryos, describing for the first time its expression in a large mammalian species. We report sheep-specific patterns of expression and a relationship with the oocyte developmental potential in terms of delayed degradation of maternal SCMC transcripts in pre-implantation embryos derived from developmentally incompetent oocytes. In addition, by determining OOEP full length cDNA by Rapid Amplification of cDNA Ends (RACE) we identified two different transcript variants (OOEP1 and OOEP2), both expressed in oocytes and early embryos, but with different somatic tissue distributions. In silico translation showed that 140 aminoacid peptide OOEP1 shares an identity with orthologous proteins ranging from 95% with the bovine to 45% with mouse. Conversely, OOEP2 contains a premature termination codon, thus representing an alternative noncoding transcript and supporting the existence of aberrant splicing during ovine oogenesis. CONCLUSIONS These findings confirm the existence of the SCMC in sheep and its key role for the oocyte developmental potential, deepening our understanding on the molecular differences underlying cytoplasmic vs nuclear maturation of the oocytes. Describing differences and overlaps in transcriptome composition between model organisms advance our comprehension of the diversity/uniformity between mammalian species during early embryonic development and provide information on genes that play important regulatory roles in fertility in nonmurine models, including the human.
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Affiliation(s)
- Daniela Bebbere
- Department of Veterinary Medicine, University of Sassari, via Vienna 2, 07100, Sassari, Italy.
| | - Federica Ariu
- Department of Veterinary Medicine, University of Sassari, via Vienna 2, 07100, Sassari, Italy.
| | - Luisa Bogliolo
- Department of Veterinary Medicine, University of Sassari, via Vienna 2, 07100, Sassari, Italy.
| | - Laura Masala
- Department of Veterinary Medicine, University of Sassari, via Vienna 2, 07100, Sassari, Italy.
| | - Ombretta Murrone
- Department of Veterinary Medicine, University of Sassari, via Vienna 2, 07100, Sassari, Italy.
| | - Mauro Fattorini
- Department of Veterinary Medicine, University of Sassari, via Vienna 2, 07100, Sassari, Italy.
| | - Laura Falchi
- Department of Veterinary Medicine, University of Sassari, via Vienna 2, 07100, Sassari, Italy.
| | - Sergio Ledda
- Department of Veterinary Medicine, University of Sassari, via Vienna 2, 07100, Sassari, Italy.
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29
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Janssenswillen S, Vandebergh W, Treer D, Willaert B, Maex M, Van Bocxlaer I, Bossuyt F. Origin and diversification of a salamander sex pheromone system. Mol Biol Evol 2014; 32:472-80. [PMID: 25415963 DOI: 10.1093/molbev/msu316] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Sex pheromones form an important facet of reproductive strategies in many organisms throughout the Animal Kingdom. One of the oldest known sex pheromones in vertebrates are proteins of the Sodefrin Precursor-like Factor (SPF) system, which already had a courtship function in early salamanders. The subsequent evolution of salamanders is characterized by a diversification in courtship and reproduction, but little is known on how the SPF pheromone system diversified in relation to changing courtship strategies. Here, we combined transcriptomic, genomic, and phylogenetic analyses to investigate the evolution of the SPF pheromone system in nine salamandrid species with distinct courtship displays. First, we show that SPF originated from vertebrate three-finger proteins and diversified through multiple gene duplications in salamanders, while remaining a single copy in frogs. Next, we demonstrate that tail-fanning newts have retained a high phylogenetic diversity of SPFs, whereas loss of tail-fanning has been associated with a reduced importance or loss of SPF expression in the cloacal region. Finally, we show that the attractant decapeptide sodefrin is cleaved from larger SPF precursors that originated by a 62 bp insertion and consequent frameshift in an ancestral Cynops lineage. This led to the birth of a new decapeptide that rapidly evolved a pheromone function independently from uncleaved proteins.
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Affiliation(s)
- Sunita Janssenswillen
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Wim Vandebergh
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Dag Treer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Bert Willaert
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Margo Maex
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Ines Van Bocxlaer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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30
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Widespread genome transcription: new possibilities for RNA therapies. Biochem Biophys Res Commun 2014; 452:294-301. [PMID: 25193698 DOI: 10.1016/j.bbrc.2014.08.139] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 08/25/2014] [Indexed: 12/15/2022]
Abstract
Comprehensive analysis of mammalian transcriptomes has surprisingly revealed that a major fraction of the RNAs produced by mammalian cells and tissues is comprised of long non-coding RNAs (lncRNAs). Such RNAs were previously disregarded as useless, but recent functional studies have revealed that they have multiple regulatory functions. A large subset of these lncRNAs are antisense to protein-coding genes; such RNAs are particularly attractive to researchers because their functions are better understood than other lncRNAs and their action can be easily modulated and engineered by modifying the antisense region. We discuss various aspects of regulation by antisense RNAs and other small nucleic acids and the challenges to bring these technologies to gene therapy. Despite several remaining issues related to delivery, RNA stability, side effects, and toxicity, the field is moving quickly towards future biotechnological and health applications. Therapies based on lncRNAs may be the key to increased cell-specificity of future gene therapies.
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Abstract
Cells use messenger RNAs (mRNAs) to ensure the accurate dissemination of genetic information encoded by DNA. Given that mRNAs largely direct the synthesis of a critical effector of cellular phenotype, i.e., proteins, tight regulation of both the quality and quantity of mRNA is a prerequisite for effective cellular homeostasis. Here, we review nonsense-mediated mRNA decay (NMD), which is the best-characterized posttranscriptional quality control mechanism that cells have evolved in their cytoplasm to ensure transcriptome fidelity. We use protein quality control as a conceptual framework to organize what is known about NMD, highlighting overarching similarities between these two polymer quality control pathways, where the protein quality control and NMD pathways intersect, and how protein quality control can suggest new avenues for research into mRNA quality control.
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Affiliation(s)
- Maximilian Wei-Lin Popp
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642;
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32
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Nonsense-mediated mRNA decay immunity can help identify human polycistronic transcripts. PLoS One 2014; 9:e91535. [PMID: 24621851 PMCID: PMC3951408 DOI: 10.1371/journal.pone.0091535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 02/13/2014] [Indexed: 11/19/2022] Open
Abstract
Eukaryotic polycistronic transcription units are rare and only a few examples are known, mostly being the outcome of serendipitous discovery. We claim that nonsense-mediated mRNA decay (NMD) immune structure is a common characteristic of polycistronic transcripts, and that this immunity is an emergent property derived from all functional CDSs. The human RefSeq transcriptome was computationally screened for transcripts capable of eliciting NMD, and which contain an additional ORF(s) potentially capable of rescuing the transcript from NMD. Transcripts were further analyzed implementing domain-based strategies in order to estimate the potential of the candidate ORF to encode a functional protein. Consequently, we predict the existence of forty nine novel polycistronic transcripts. Experimental verification was carried out utilizing two different types of analyses. First, five Gene Expression Omnibus (GEO) datasets from published NMD-inhibition studies were used, aiming to explore whether a given mRNA is indeed insensitive to NMD. All known bicistronic transcripts and eleven out of the twelve predicted genes that were analyzed, displayed NMD insensitivity using various NMD inhibitors. For three genes, a mixed expression pattern was observed presenting both NMD sensitivity and insensitivity in different cell types. Second, we used published global translation initiation sequencing data from HEK293 cells to verify the existence of translation initiation sites in our predicted polycistronic genes. In five of our genes, the predicted rescuing uORFs are indeed identified as translation initiation sites, and in two additional genes, one of two predicted rescuing uORF is verified. These results validate our computational analysis and reinforce the possibility that NMD-immune architecture is a parameter by which polycistronic genes can be identified. Moreover, we present evidence for NMD-mediated regulation controlling the production of one or more proteins encoded in the polycistronic transcript.
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33
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Drechsel G, Kahles A, Kesarwani AK, Stauffer E, Behr J, Drewe P, Rätsch G, Wachter A. Nonsense-mediated decay of alternative precursor mRNA splicing variants is a major determinant of the Arabidopsis steady state transcriptome. THE PLANT CELL 2013; 25:3726-42. [PMID: 24163313 PMCID: PMC3877825 DOI: 10.1105/tpc.113.115485] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 09/17/2013] [Accepted: 10/07/2013] [Indexed: 05/18/2023]
Abstract
The nonsense-mediated decay (NMD) surveillance pathway can recognize erroneous transcripts and physiological mRNAs, such as precursor mRNA alternative splicing (AS) variants. Currently, information on the global extent of coupled AS and NMD remains scarce and even absent for any plant species. To address this, we conducted transcriptome-wide splicing studies using Arabidopsis thaliana mutants in the NMD factor homologs UP FRAMESHIFT1 (UPF1) and UPF3 as well as wild-type samples treated with the translation inhibitor cycloheximide. Our analyses revealed that at least 17.4% of all multi-exon, protein-coding genes produce splicing variants that are targeted by NMD. Moreover, we provide evidence that UPF1 and UPF3 act in a translation-independent mRNA decay pathway. Importantly, 92.3% of the NMD-responsive mRNAs exhibit classical NMD-eliciting features, supporting their authenticity as direct targets. Genes generating NMD-sensitive AS variants function in diverse biological processes, including signaling and protein modification, for which NaCl stress-modulated AS-NMD was found. Besides mRNAs, numerous noncoding RNAs and transcripts derived from intergenic regions were shown to be NMD responsive. In summary, we provide evidence for a major function of AS-coupled NMD in shaping the Arabidopsis transcriptome, having fundamental implications in gene regulation and quality control of transcript processing.
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Affiliation(s)
- Gabriele Drechsel
- Center for Plant Molecular Biology, University of Tübingen, 72076 Tuebingen, Germany
| | - André Kahles
- Computational Biology Center, Sloan-Kettering Institute, New York, New York 10065
| | - Anil K. Kesarwani
- Center for Plant Molecular Biology, University of Tübingen, 72076 Tuebingen, Germany
| | - Eva Stauffer
- Center for Plant Molecular Biology, University of Tübingen, 72076 Tuebingen, Germany
| | - Jonas Behr
- Computational Biology Center, Sloan-Kettering Institute, New York, New York 10065
| | - Philipp Drewe
- Computational Biology Center, Sloan-Kettering Institute, New York, New York 10065
| | - Gunnar Rätsch
- Computational Biology Center, Sloan-Kettering Institute, New York, New York 10065
| | - Andreas Wachter
- Center for Plant Molecular Biology, University of Tübingen, 72076 Tuebingen, Germany
- Address correspondence to
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34
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Identification of a PTC-containing DlRan transcript and its differential expression during somatic embryogenesis in Dimocarpus longan. Gene 2013; 529:37-44. [DOI: 10.1016/j.gene.2013.07.091] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 05/19/2013] [Accepted: 07/25/2013] [Indexed: 11/17/2022]
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35
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Bouyacoub Y, Zribi H, Azzouz H, Nasrallah F, Abdelaziz RB, Kacem M, Rekaya B, Messaoud O, Romdhane L, Charfeddine C, Bouziri M, Bouziri S, Tebib N, Mokni M, Kaabachi N, Boubaker S, Abdelhak S. Novel and recurrent mutations in the TAT gene in Tunisian families affected with Richner-Hanhart syndrome. Gene 2013; 529:45-9. [PMID: 23954227 DOI: 10.1016/j.gene.2013.07.066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 06/20/2013] [Accepted: 07/17/2013] [Indexed: 12/01/2022]
Abstract
Tyrosinemia type II, also designated as oculocutaneous tyrosinemia or Richner-Hanhart syndrome (RHS), is a very rare autosomal recessive disorder. In the present study, we report clinical features and molecular genetic investigation of the tyrosine aminotransferase (TAT) gene in two young patients, both born to consanguineous unions between first-degree cousins. These two unrelated families originated from Northern and Southern Tunisia. The clinical diagnosis was based on the observation of several complications related to Richner-Hanhart syndrome: recurrent eye redness, tearing and burning pain, photophobia, bilateral pseudodendritic keratitis, an erythematous and painful focal palmo-plantar hyperkeratosis and a mild delay of mental development. The diagnosis was confirmed by biochemical analysis. Sequencing of the TAT gene revealed the presence of a previously reported missense mutation (c.452G>A, p.Cys151Tyr) in a Tunisian family, and a novel G duplication (c.869dupG, p.Trp291Leufs 6). Early diagnosis of RHS and protein-restricted diet are crucial to reduce the risk and the severity of long-term complications of hypertyrosinemia such as intellectual disability.
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Affiliation(s)
- Yosra Bouyacoub
- Université Tunis El Manar, Institut Pasteur de Tunis, LR11IPT05, Génomique Biomédicale et Oncogénétique, 1002 Tunis,Tunisia; Université de Monastire, Institut Supérieur de Biotechnologie, Monastir 5000, Tunisia
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Wong JJL, Ritchie W, Ebner OA, Selbach M, Wong JWH, Huang Y, Gao D, Pinello N, Gonzalez M, Baidya K, Thoeng A, Khoo TL, Bailey CG, Holst J, Rasko JEJ. Orchestrated intron retention regulates normal granulocyte differentiation. Cell 2013; 154:583-95. [PMID: 23911323 DOI: 10.1016/j.cell.2013.06.052] [Citation(s) in RCA: 334] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 05/01/2013] [Accepted: 06/28/2013] [Indexed: 12/11/2022]
Abstract
Intron retention (IR) is widely recognized as a consequence of mis-splicing that leads to failed excision of intronic sequences from pre-messenger RNAs. Our bioinformatic analyses of transcriptomic and proteomic data of normal white blood cell differentiation reveal IR as a physiological mechanism of gene expression control. IR regulates the expression of 86 functionally related genes, including those that determine the nuclear shape that is unique to granulocytes. Retention of introns in specific genes is associated with downregulation of splicing factors and higher GC content. IR, conserved between human and mouse, led to reduced mRNA and protein levels by triggering the nonsense-mediated decay (NMD) pathway. In contrast to the prevalent view that NMD is limited to mRNAs encoding aberrant proteins, our data establish that IR coupled with NMD is a conserved mechanism in normal granulopoiesis. Physiological IR may provide an energetically favorable level of dynamic gene expression control prior to sustained gene translation.
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Affiliation(s)
- Justin J-L Wong
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown 2050, Australia
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Soreq L, Bergman H, Israel Z, Soreq H. Deep brain stimulation modulates nonsense-mediated RNA decay in Parkinson's patients leukocytes. BMC Genomics 2013; 14:478. [PMID: 23865419 PMCID: PMC3723527 DOI: 10.1186/1471-2164-14-478] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 07/12/2013] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Nonsense-Mediated decay (NMD) selectively degrades mRNA transcripts that carry premature stop codons. NMD is often triggered by alternative splicing (AS) modifications introducing such codons. NMD plays an important regulatory role in brain neurons, but the in vivo dynamics of AS and NMD changes in neurological diseases and under treatment were scarcely explored. RESULTS Here, we report exon arrays analysis of leukocyte mRNA AS events prior to and following Deep Brain Stimulation (DBS) neurosurgery, which efficiently improves the motor symptoms of Parkinson's disease (PD), the leading movement disorder, and is increasingly applied to treat other diseases. We also analyzed publicly available exon array dataset of whole blood cells from mixed early and advanced PD patients. Our in-house exon array dataset of leukocyte transcripts was derived from advanced PD patients' pre- and post-DBS stimulation and matched healthy control volunteers. The mixed cohort exhibited 146 AS changes in 136 transcripts compared to controls, including 9 NMD protein-level assessed events. In comparison, PD patients from our advanced cohort differed from healthy controls by 319 AS events in 280 transcripts, assessed as inducing 27 protein-level NMD events. DBS stimulation induced 254 AS events in 229 genes as compared to the pre-DBS state including 44 NMD inductions. A short, one hour electrical stimulus cessation caused 234 AS changes in 125 genes compared to ON-stimulus state, 22 of these were assessed for NMD. Functional analysis highlighted disease-induced DNA damage and inflammatory control and its reversal under ON and OFF stimulus as well as alternative splicing in all the tested states. CONCLUSIONS The study findings indicate a potential role for NMD both in PD and following electrical brain stimulation. Furthermore, our current observations entail future implications for developing therapies for PD, and for interfering with the impaired molecular mechanisms that underlie PD and other neurodegenerative and neurological disorders, as well as DBS-treatable conditions in general.
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Affiliation(s)
- Lilach Soreq
- Department of Medical Neurobiology, Institute of Medical Research Israel-Canada, Hadassah Medical School, The Hebrew University, Jerusalem, Israel
| | - Hagai Bergman
- Department of Medical Neurobiology, Institute of Medical Research Israel-Canada, Hadassah Medical School, The Hebrew University, Jerusalem, Israel
- The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University, Jerusalem 91904, Israel
| | - Zvi Israel
- Center for Functional & Restorative Neurosurgery, Department of Neurosurgery, Hadassah University Hospital, Jerusalem, Israel
| | - Hermona Soreq
- The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University, Jerusalem 91904, Israel
- The Department of Biological Chemistry, The Life Sciences Institute, The Hebrew University of Jerusalem, Jerusalem, Israel
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38
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Gonzàlez-Porta M, Frankish A, Rung J, Harrow J, Brazma A. Transcriptome analysis of human tissues and cell lines reveals one dominant transcript per gene. Genome Biol 2013; 14:R70. [PMID: 23815980 PMCID: PMC4053754 DOI: 10.1186/gb-2013-14-7-r70] [Citation(s) in RCA: 183] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 07/01/2013] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND RNA sequencing has opened new avenues for the study of transcriptome composition. Significant evidence has accumulated showing that the human transcriptome contains in excess of a hundred thousand different transcripts. However, it is still not clear to what extent this diversity prevails when considering the relative abundances of different transcripts from the same gene. RESULTS Here we show that, in a given condition, most protein coding genes have one major transcript expressed at significantly higher level than others, that in human tissues the major transcripts contribute almost 85 percent to the total mRNA from protein coding loci, and that often the same major transcript is expressed in many tissues. We detect a high degree of overlap between the set of major transcripts and a recently published set of alternatively spliced transcripts that are predicted to be translated utilizing proteomic data. Thus, we hypothesize that although some minor transcripts may play a functional role, the major ones are likely to be the main contributors to the proteome. However, we still detect a non-negligible fraction of protein coding genes for which the major transcript does not code a protein. CONCLUSIONS Overall, our findings suggest that the transcriptome from protein coding loci is dominated by one transcript per gene and that not all the transcripts that contribute to transcriptome diversity are equally likely to contribute to protein diversity. This observation can help to prioritize candidate targets in proteomics research and to predict the functional impact of the detected changes in variation studies.
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Hirschfeld M, Zhang B, Jaeger M, Stamm S, Erbes T, Mayer S, Tong X, Stickeler E. Hypoxia-dependent mRNA expression pattern of splicing factor YT521 and its impact on oncological important target gene expression. Mol Carcinog 2013; 53:883-92. [PMID: 23765422 DOI: 10.1002/mc.22045] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 04/19/2013] [Indexed: 11/06/2022]
Abstract
The ubiquitously expressed splicing factor YT521 (YTHDC1) is characterized by alternatively spliced isoforms with regulatory impact on cancer-associated gene expression. Our recent findings account for the prognostic significance of YT521 in endometrial cancer. In this study, we investigated the hypoxia-dependency of YT521 expression as well as its differential isoform activities on oncological important target genes. YT521's potential regulatory influence on splicing was investigated by a minigene assay for the specific target gene CD44. Functional splicing analysis was performed by YT521 knock-down or overexpression, respectively. In addition, YT521 expression was determined under hypoxia. The two protein-generating YT521 mRNA isoforms 1 and 2 caused a comparable, specific induction of CD44v alternative splicing (P < 0.01). In a number of oncological target genes, YT521 upregulation significantly altered BRCA2 expression pattern, while YT521 knock-down created a significant regulatory impact on PGR expression, respectively. Hypoxia induced a specific switch towards the processing of two non-protein-coding mRNA variants, of which one is described for the first time in this study. The presented study underlines the comparable regulatory potential of both YT521 isoforms 1 and 2, on the investigated target genes in vivo and in vitro. Hypoxia induces a specific switch in YT521 expression pattern towards the two non-protein coding mRNA variants, the already characterized isoform 3 and the newly discovered exon 8-skipping isoform. The altered YT521 alternative splicing is functionally coupled with nonsense-mediated decay and can be interpreted as regulated unproductive splicing and transcription with consecutive impact on the processing of specific cancer-associated genes, such as BRCA2 and PGR.
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Affiliation(s)
- Marc Hirschfeld
- Gynecological Hospital, University Medical Center Freiburg, Freiburg, Germany; German Cancer Research Center, Heidelberg, Germany
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40
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Aparicio LA, Abella V, Valladares M, Figueroa A. Posttranscriptional regulation by RNA-binding proteins during epithelial-to-mesenchymal transition. Cell Mol Life Sci 2013; 70:4463-77. [PMID: 23715860 PMCID: PMC3827902 DOI: 10.1007/s00018-013-1379-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 05/10/2013] [Accepted: 05/16/2013] [Indexed: 12/22/2022]
Abstract
Epithelial-to-mesenchymal transition (EMT), one of the crucial steps for carcinoma cells to acquire invasive capacity, results from the disruption of cell–cell contacts and the acquisition of a motile mesenchymal phenotype. Although the transcriptional events controlling EMT have been extensively studied, in recent years, several posttranscriptional mechanisms have emerged as critical in the regulation of EMT during tumor progression. In this review, we highlight the regulation of posttranscriptional events in EMT by RNA-binding proteins (RBPs). RBPs are responsible for controlling pre-mRNA splicing, capping, and polyadenylation, as well as mRNA export, turnover, localization, and translation. We discuss the most relevant aspects of RBPs controlling the metabolism of EMT-related mRNAs, and describe the implication of novel posttranscriptional mechanisms regulating EMT in response to different signaling pathways. Novel insight into posttranscriptional regulation of EMT by RBPs is uncovering new therapeutic targets in cancer invasion and metastasis.
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Affiliation(s)
- Luis A Aparicio
- Servizo de Oncología Médica, Complejo Hospitalario Universitario A Coruña (CHUAC), SERGAS, A Coruña, Spain
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41
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Nakano K, Ando T, Yamagishi M, Yokoyama K, Ishida T, Ohsugi T, Tanaka Y, Brighty DW, Watanabe T. Viral interference with host mRNA surveillance, the nonsense-mediated mRNA decay (NMD) pathway, through a new function of HTLV-1 Rex: implications for retroviral replication. Microbes Infect 2013; 15:491-505. [PMID: 23541980 DOI: 10.1016/j.micinf.2013.03.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 03/15/2013] [Accepted: 03/18/2013] [Indexed: 01/08/2023]
Abstract
Nonsense-mediated mRNA decay (NMD) is an essential and conserved cellular mRNA quality control mechanism. RNA signals to express viral genes from overlapping open reading frames potentially initiate NMD, nevertheless it is not clear whether viral RNAs are sensitive to NMD or if viruses have evolved mechanisms to evade NMD. Here we demonstrate that the genomic and full-length mRNAs of Human-T-cell Leukemia Virus type-I (HTLV-1), a retrovirus responsible for Adult T-cell Leukemia (ATL), are sensitive to NMD. They exhibit accelerated turnover in NMD-activated cells, while siRNA-mediated knockdown of NMD-master-regulator, UPF1, promotes enhanced stability of them. These effects on RNA stability were recapitulated by a reporter construct encoding the HTLV-1 translational frameshift signal of gag-pol. In agreement with the RNA stability, viral protein expression from the integrated provirus was inversely correlated with cellular NMD activity. We further demonstrated that the viral RNA-binding protein, Rex, approves the stability of viral RNA by inhibiting NMD. Significantly, Rex establishes a general block to NMD, as both NMD-responsive reporter transcripts and natural host-encoded NMD substrates were stabilized in the presence of Rex. Thus, we suggest that Rex not only stabilizes viral transcripts, but also perturbs cellular mRNA metabolism and host cell homeostasis via inhibition of NMD.
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Affiliation(s)
- Kazumi Nakano
- Laboratory of Tumor Cell Biology, Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Minatoku, Tokyo, Japan
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42
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Melo JO, Lana UGP, Piñeros MA, Alves VMC, Guimarães CT, Liu J, Zheng Y, Zhong S, Fei Z, Maron LG, Schaffert RE, Kochian LV, Magalhaes JV. Incomplete transfer of accessory loci influencing SbMATE expression underlies genetic background effects for aluminum tolerance in sorghum. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 73:276-88. [PMID: 22989115 DOI: 10.1111/tpj.12029] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 09/10/2012] [Accepted: 09/13/2012] [Indexed: 05/08/2023]
Abstract
Impaired root development caused by aluminum (Al) toxicity is a major cause of grain yield reduction in crops cultivated on acid soils, which are widespread worldwide. In sorghum, the major Al-tolerance locus, AltSB , is due to the function of SbMATE, which is an Al-activated root citrate transporter. Here we performed a molecular and physiological characterization of various AltSB donors and near-isogenic lines harboring various AltSB alleles. We observed a partial transfer of Al tolerance from the parents to the near-isogenic lines that was consistent across donor alleles, emphasizing the occurrence of strong genetic background effects related to AltSB . This reduction in tolerance was variable, with a 20% reduction being observed when highly Al-tolerant lines were the AltSB donors, and a reduction as great as 70% when other AltSB alleles were introgressed. This reduction in Al tolerance was closely correlated with a reduction in SbMATE expression in near-isogenic lines, suggesting incomplete transfer of loci acting in trans on SbMATE. Nevertheless, AltSB alleles from the highly Al-tolerant sources SC283 and SC566 were found to retain high SbMATE expression, presumably via elements present within or near the AltSB locus, resulting in significant transfer of the Al-tolerance phenotype to the derived near-isogenic lines. Allelic effects could not be explained by coding region polymorphisms, although occasional mutations may affect Al tolerance. Finally, we report on the extensive occurrence of alternative splicing for SbMATE, which may be an important component regulating SbMATE expression in sorghum by means of the nonsense-mediated RNA decay pathway.
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Affiliation(s)
- Janaina O Melo
- Embrapa Maize and Sorghum, Road. MG 424, km 65, 35701-970, Sete Lagoas, Minas Gerais, Brazil
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil
| | - Ubiraci G P Lana
- Embrapa Maize and Sorghum, Road. MG 424, km 65, 35701-970, Sete Lagoas, Minas Gerais, Brazil
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil
| | - Miguel A Piñeros
- US Department of Agriculture - Agricultural Research Service, Robert W. Holley Center for Agriculture and Health, Cornell University, Ithaca, NY, 14853, USA
| | - Vera M C Alves
- Embrapa Maize and Sorghum, Road. MG 424, km 65, 35701-970, Sete Lagoas, Minas Gerais, Brazil
| | - Claudia T Guimarães
- Embrapa Maize and Sorghum, Road. MG 424, km 65, 35701-970, Sete Lagoas, Minas Gerais, Brazil
| | - Jiping Liu
- US Department of Agriculture - Agricultural Research Service, Robert W. Holley Center for Agriculture and Health, Cornell University, Ithaca, NY, 14853, USA
| | - Yi Zheng
- Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, NY, 14853, USA
| | - Silin Zhong
- Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, NY, 14853, USA
| | - Zhangjun Fei
- US Department of Agriculture - Agricultural Research Service, Robert W. Holley Center for Agriculture and Health, Cornell University, Ithaca, NY, 14853, USA
- Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, NY, 14853, USA
| | - Lyza G Maron
- US Department of Agriculture - Agricultural Research Service, Robert W. Holley Center for Agriculture and Health, Cornell University, Ithaca, NY, 14853, USA
| | - Robert E Schaffert
- Embrapa Maize and Sorghum, Road. MG 424, km 65, 35701-970, Sete Lagoas, Minas Gerais, Brazil
| | - Leon V Kochian
- US Department of Agriculture - Agricultural Research Service, Robert W. Holley Center for Agriculture and Health, Cornell University, Ithaca, NY, 14853, USA
| | - Jurandir V Magalhaes
- Embrapa Maize and Sorghum, Road. MG 424, km 65, 35701-970, Sete Lagoas, Minas Gerais, Brazil
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Abstract
Frameshifting results from two main mechanisms: genomic insertions or deletions (indels) or programmed ribosomal frameshifting. Whereas indels can disrupt normal protein function, programmed ribosomal frameshifting can result in dual-coding genes, each of which can produce multiple functional products. Here, I summarize technical advances that have made it possible to identify programmed ribosomal frameshifting events in a systematic way. The results of these studies suggest that such frameshifting occurs in all genomes, and I will discuss methods that could help characterize the resulting alternative proteomes.
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Affiliation(s)
- Robin Ketteler
- MRC Laboratory for Molecular Cell Biology, Translational Research Resource Centre, University College London London, UK
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44
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Palacios IM. Nonsense-mediated mRNA decay: from mechanistic insights to impacts on human health. Brief Funct Genomics 2012; 12:25-36. [PMID: 23148322 DOI: 10.1093/bfgp/els051] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Cells are able to recognize and degrade aberrant transcripts in order to self-protect from potentially toxic proteins. Various pathways detect aberrant RNAs in the cytoplasm and are dependent on translation. One of these pathways is the nonsense-mediated RNA decay (NMD). NMD is a surveillance mechanism that degrades transcripts containing nonsense mutations, preventing the translation of possibly harmful truncated proteins. For example, the degradation of a nonsense harming β-globin allele renders normal phenotypes. On the other hand, regulating NMD is also important in those cases when the produced aberrant protein is better than having no protein, as it has been shown for cystic fibrosis. These findings reflect the important role for NMD in human health. In addition, NMD controls the levels of physiologic transcripts, which defines this pathway as a novel gene expression regulator, with huge impact on homeostasis, cell growth and development. While the mechanistic details of NMD are being gradually understood, the physiological role of this RNA surveillance pathway still remains largely unknown. This is a brief and simplified review on various aspects of NMD, such as the nature of the NMD targets, the mechanism of target degradation and the links between NMD and cell growth, animal development and diseases.
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Affiliation(s)
- Isabel M Palacios
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK.
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45
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Bicknell AA, Cenik C, Chua HN, Roth FP, Moore MJ. Introns in UTRs: why we should stop ignoring them. Bioessays 2012; 34:1025-34. [PMID: 23108796 DOI: 10.1002/bies.201200073] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although introns in 5'- and 3'-untranslated regions (UTRs) are found in many protein coding genes, rarely are they considered distinctive entities with specific functions. Indeed, mammalian transcripts with 3'-UTR introns are often assumed nonfunctional because they are subject to elimination by nonsense-mediated decay (NMD). Nonetheless, recent findings indicate that 5'- and 3'-UTR intron status is of significant functional consequence for the regulation of mammalian genes. Therefore these features should be ignored no longer.
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Affiliation(s)
- Alicia A Bicknell
- Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
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46
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Biamonti G, Bonomi S, Gallo S, Ghigna C. Making alternative splicing decisions during epithelial-to-mesenchymal transition (EMT). Cell Mol Life Sci 2012; 69:2515-26. [PMID: 22349259 PMCID: PMC11115103 DOI: 10.1007/s00018-012-0931-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Revised: 01/22/2012] [Accepted: 01/24/2012] [Indexed: 12/22/2022]
Abstract
Alternative splicing generates multiple mRNAs from a single transcript and is a major contributor to proteomic diversity and to the control of gene expression in complex organisms. Not surprisingly, this post-transcriptional event is tightly regulated in different tissues and developmental stages. An increasing body of evidences supports a causative role of aberrant alternative splicing in cancer. However, very little is known about its impact on cellular processes crucially involved in tumor progression. The aim of this review is to discuss the link between alternative splicing and the epithelial-to-mesenchymal transition (EMT), one of the major routes by which cancer cells acquire invasive capabilities and become metastatic. We begin with a brief overview of alternative splicing. Next, we discuss alternative splicing factors that regulate EMT. Finally, we provide examples of target genes presenting alternative splicing changes that contribute to the morphological conversions in the EMT process.
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Affiliation(s)
- Giuseppe Biamonti
- Istituto di Genetica Molecolare – Consiglio Nazionale delle Ricerche, via Abbiategrasso 207, 27100 Pavia, Italy
| | - Serena Bonomi
- Istituto di Genetica Molecolare – Consiglio Nazionale delle Ricerche, via Abbiategrasso 207, 27100 Pavia, Italy
| | - Stefania Gallo
- Istituto di Genetica Molecolare – Consiglio Nazionale delle Ricerche, via Abbiategrasso 207, 27100 Pavia, Italy
| | - Claudia Ghigna
- Istituto di Genetica Molecolare – Consiglio Nazionale delle Ricerche, via Abbiategrasso 207, 27100 Pavia, Italy
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47
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Weischenfeldt J, Waage J, Tian G, Zhao J, Damgaard I, Jakobsen JS, Kristiansen K, Krogh A, Wang J, Porse BT. Mammalian tissues defective in nonsense-mediated mRNA decay display highly aberrant splicing patterns. Genome Biol 2012; 13:R35. [PMID: 22624609 PMCID: PMC3446288 DOI: 10.1186/gb-2012-13-5-r35] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 05/06/2012] [Accepted: 05/24/2012] [Indexed: 11/11/2022] Open
Abstract
Background Nonsense-mediated mRNA decay (NMD) affects the outcome of alternative splicing by degrading mRNA isoforms with premature termination codons. Splicing regulators constitute important NMD targets; however, the extent to which loss of NMD causes extensive deregulation of alternative splicing has not previously been assayed in a global, unbiased manner. Here, we combine mouse genetics and RNA-seq to provide the first in vivo analysis of the global impact of NMD on splicing patterns in two primary mouse tissues ablated for the NMD factor UPF2. Results We developed a bioinformatic pipeline that maps RNA-seq data to a combinatorial exon database, predicts NMD-susceptibility for mRNA isoforms and calculates the distribution of major splice isoform classes. We present a catalog of NMD-regulated alternative splicing events, showing that isoforms of 30% of all expressed genes are upregulated in NMD-deficient cells and that NMD targets all major splicing classes. Importantly, NMD-dependent effects are not restricted to premature termination codon+ isoforms but also involve an abundance of splicing events that do not generate premature termination codons. Supporting their functional importance, the latter events are associated with high intronic conservation. Conclusions Our data demonstrate that NMD regulates alternative splicing outcomes through an intricate web of splicing regulators and that its loss leads to the deregulation of a panoply of splicing events, providing novel insights into its role in core- and tissue-specific regulation of gene expression. Thus, our study extends the importance of NMD from an mRNA quality pathway to a regulator of several layers of gene expression.
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Affiliation(s)
- Joachim Weischenfeldt
- The Finsen Laboratory, Rigshospitalet, Faculty of Health Sciences, University of Copenhagen, DK2200 Copenhagen, Denmark.
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48
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Abstract
The intron–exon architecture of many eukaryotic genes raises the intriguing question of whether this unique organization serves any function, or is it simply a result of the spread of functionless introns in eukaryotic genomes. In this review, we show that introns in contemporary species fulfill a broad spectrum of functions, and are involved in virtually every step of mRNA processing. We propose that this great diversity of intronic functions supports the notion that introns were indeed selfish elements in early eukaryotes, but then independently gained numerous functions in different eukaryotic lineages. We suggest a novel criterion of evolutionary conservation, dubbed intron positional conservation, which can identify functional introns.
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Affiliation(s)
- Michal Chorev
- Department of Genetics, The Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem Jerusalem, Israel
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49
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Marquez Y, Brown JWS, Simpson C, Barta A, Kalyna M. Transcriptome survey reveals increased complexity of the alternative splicing landscape in Arabidopsis. Genome Res 2012; 22:1184-95. [PMID: 22391557 PMCID: PMC3371709 DOI: 10.1101/gr.134106.111] [Citation(s) in RCA: 563] [Impact Index Per Article: 46.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Alternative splicing (AS) is a key regulatory mechanism that contributes to transcriptome and proteome diversity. As very few genome-wide studies analyzing AS in plants are available, we have performed high-throughput sequencing of a normalized cDNA library which resulted in a high coverage transcriptome map of Arabidopsis. We detect ∼150,000 splice junctions derived mostly from typical plant introns, including an eightfold increase in the number of U12 introns (2069). Around 61% of multiexonic genes are alternatively spliced under normal growth conditions. Moreover, we provide experimental validation of 540 AS transcripts (from 256 genes coding for important regulatory factors) using high-resolution RT-PCR and Sanger sequencing. Intron retention (IR) is the most frequent AS event (∼40%), but many IRs have relatively low read coverage and are less well-represented in assembled transcripts. Additionally, ∼51% of Arabidopsis genes produce AS transcripts which do not involve IR. Therefore, the significance of IR in generating transcript diversity was generally overestimated in previous assessments. IR analysis allowed the identification of a large set of cryptic introns inside annotated coding exons. Importantly, a significant fraction of these cryptic introns are spliced out in frame, indicating a role in protein diversity. Furthermore, we show extensive AS coupled to nonsense-mediated decay in AFC2, encoding a highly conserved LAMMER kinase which phosphorylates splicing factors, thus establishing a complex loop in AS regulation. We provide the most comprehensive analysis of AS to date which will serve as a valuable resource for the plant community to study transcriptome complexity and gene regulation.
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Affiliation(s)
- Yamile Marquez
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna, Austria
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50
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Kalyna M, Simpson CG, Syed NH, Lewandowska D, Marquez Y, Kusenda B, Marshall J, Fuller J, Cardle L, McNicol J, Dinh HQ, Barta A, Brown JWS. Alternative splicing and nonsense-mediated decay modulate expression of important regulatory genes in Arabidopsis. Nucleic Acids Res 2012; 40:2454-69. [PMID: 22127866 PMCID: PMC3315328 DOI: 10.1093/nar/gkr932] [Citation(s) in RCA: 327] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 09/22/2011] [Accepted: 10/10/2011] [Indexed: 11/26/2022] Open
Abstract
Alternative splicing (AS) coupled to nonsense-mediated decay (NMD) is a post-transcriptional mechanism for regulating gene expression. We have used a high-resolution AS RT-PCR panel to identify endogenous AS isoforms which increase in abundance when NMD is impaired in the Arabidopsis NMD factor mutants, upf1-5 and upf3-1. Of 270 AS genes (950 transcripts) on the panel, 102 transcripts from 97 genes (32%) were identified as NMD targets. Extrapolating from these data around 13% of intron-containing genes in the Arabidopsis genome are potentially regulated by AS/NMD. This cohort of naturally occurring NMD-sensitive AS transcripts also allowed the analysis of the signals for NMD in plants. We show the importance of AS in introns in 5' or 3'UTRs in modulating NMD-sensitivity of mRNA transcripts. In particular, we identified upstream open reading frames overlapping the main start codon as a new trigger for NMD in plants and determined that NMD is induced if 3'-UTRs were >350 nt. Unexpectedly, although many intron retention transcripts possess NMD features, they are not sensitive to NMD. Finally, we have shown that AS/NMD regulates the abundance of transcripts of many genes important for plant development and adaptation including transcription factors, RNA processing factors and stress response genes.
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Affiliation(s)
- Maria Kalyna
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Craig G. Simpson
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Naeem H. Syed
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Dominika Lewandowska
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Yamile Marquez
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Branislav Kusenda
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Jacqueline Marshall
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - John Fuller
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Linda Cardle
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Jim McNicol
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Huy Q. Dinh
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - Andrea Barta
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
| | - John W. S. Brown
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria, Cell and Molecular Sciences, The James Hutton Institute, Division of Plant Sciences, University of Dundee at JHI, Biomathematics and Statistics Scotland at JHI, Invergowrie, Dundee DD2 5DA, Scotland, UK and Center for Integrative Bioinformatics, Max F. Perutz Laboratories, Medical University of Vienna, University of Vienna, University of Veterinary Medicine Vienna, Dr. Bohr-Gasse 9/3, A-1030 Vienna, Austria
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