1
|
Capitanchik C, Wilkins OG, Wagner N, Gagneur J, Ule J. From computational models of the splicing code to regulatory mechanisms and therapeutic implications. Nat Rev Genet 2025; 26:171-190. [PMID: 39358547 DOI: 10.1038/s41576-024-00774-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/27/2024] [Indexed: 10/04/2024]
Abstract
Since the discovery of RNA splicing and its role in gene expression, researchers have sought a set of rules, an algorithm or a computational model that could predict the splice isoforms, and their frequencies, produced from any transcribed gene in a specific cellular context. Over the past 30 years, these models have evolved from simple position weight matrices to deep-learning models capable of integrating sequence data across vast genomic distances. Most recently, new model architectures are moving the field closer to context-specific alternative splicing predictions, and advances in sequencing technologies are expanding the type of data that can be used to inform and interpret such models. Together, these developments are driving improved understanding of splicing regulatory mechanisms and emerging applications of the splicing code to the rational design of RNA- and splicing-based therapeutics.
Collapse
Affiliation(s)
- Charlotte Capitanchik
- The Francis Crick Institute, London, UK
- UK Dementia Research Institute at King's College London, London, UK
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, UK
| | - Oscar G Wilkins
- The Francis Crick Institute, London, UK
- UCL Queen Square Motor Neuron Disease Centre, Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Nils Wagner
- School of Computation, Information and Technology, Technical University of Munich, Garching, Germany
- Helmholtz Association - Munich School for Data Science (MUDS), Munich, Germany
| | - Julien Gagneur
- School of Computation, Information and Technology, Technical University of Munich, Garching, Germany.
- Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany.
- Computational Health Center, Helmholtz Center Munich, Neuherberg, Germany.
| | - Jernej Ule
- The Francis Crick Institute, London, UK.
- UK Dementia Research Institute at King's College London, London, UK.
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, UK.
- National Institute of Chemistry, Ljubljana, Slovenia.
| |
Collapse
|
2
|
Kenny CJ, McGurk MP, Schüler S, Cordero A, Laubinger S, Burge CB. LUC7 proteins define two major classes of 5' splice sites in animals and plants. Nat Commun 2025; 16:1574. [PMID: 39979239 PMCID: PMC11842720 DOI: 10.1038/s41467-025-56577-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 01/21/2025] [Indexed: 02/22/2025] Open
Abstract
Mutation or deletion of the U1 snRNP-associated factor LUC7L2 is associated with myeloid neoplasms, and knockout of LUC7L2 alters cellular metabolism. Here, we show that members of the LUC7 protein family differentially regulate two major classes of 5' splice sites (5'SS) and broadly regulate mRNA splicing in both human cell lines and leukemias with LUC7L2 copy number variation. We describe distinctive 5'SS features of exons impacted by the three human LUC7 paralogs: LUC7L2 and LUC7L enhance splicing of "right-handed" 5'SS with stronger consensus matching on the intron side of the near invariant /GU, while LUC7L3 enhances splicing of "left-handed" 5'SS with stronger consensus matching upstream of the /GU. We validated our model of sequence-specific 5'SS regulation both by mutating splice sites and swapping domains between human LUC7 proteins. Evolutionary analysis indicates that the LUC7L2/LUC7L3 subfamilies evolved before the split between animals and plants. Analysis of Arabidopsis thaliana mutants confirmed that plant LUC7 orthologs possess similar specificity to their human counterparts, indicating that 5'SS regulation by LUC7 proteins is highly conserved.
Collapse
Affiliation(s)
- Connor J Kenny
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Michael P McGurk
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sandra Schüler
- Institute of Biology, Department of Genetics, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Aidan Cordero
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sascha Laubinger
- Institute of Biology, Department of Genetics, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Christopher B Burge
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
3
|
Peruzzo P, Bergamin N, Bon M, Cappelli S, Longo A, Goina E, Stuani C, Buratti E, Dardis A. Rescue of common and rare exon 2 skipping variants of the GAA gene using modified U1 snRNA. Mol Med 2025; 31:45. [PMID: 39905333 PMCID: PMC11796170 DOI: 10.1186/s10020-025-01090-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Accepted: 01/16/2025] [Indexed: 02/06/2025] Open
Abstract
BACKGROUND Pompe disease (PD) is an autosomal recessive lysosomal storage disorder caused by the deficient activity of acid alpha glucosidase (GAA) enzyme due to mutations in the GAA gene. As a result, undigested glycogen accumulates within lysosomes causing their dysfunction. From a clinical point of view, the disease can be classified in infantile-onset (IO) and late-onset (LO) forms. The common GAA c.-32-13T>G variant, found in 40-70% of LO-PD alleles, is a leaky splicing mutation interfering with the correct GAA exon 2 recognition by the spliceosome leading to the production of non-functional GAA transcripts. In this study, we used modified, GAA-tailored U1 snRNAs to correct the aberrant splicing determined by the c.-32-13T>G and other GAA exon 2-skipping mutations. METHODS A set of constructs expressing 5 different engineered U1 snRNAs was generated. A functional splicing assay using a GAA hybrid minigene carrying different variants known to affect GAA exon 2 splicing was used to test the effect of engineered U1 snRNAs on exon 2 inclusion. The effect on endogenously expressed GAA transcript and GAA enzymatic activity was assessed by transfecting patient-derived fibroblasts bearing the common c.-32-13T>G with the best performing modified U1 snRNA. RESULTS Modified U1-3, U1+1 and U1+6 snRNAs were all able to increase, in a dose-dependent manner, the inclusion of exon 2 within the transcript derived from the GAA minigene harbouring the c.-32-13T>G variant. The U1+1 was the most effective one (2,5 fold increase). Moreover, U1+1 snRNA partially rescued the correct splicing of GAA minigenes harbouring mutations that affect the 3'ss (c.-32-3C>G, c.-32-2A>G) and the 5'ss (c.546G>A, c.546G>C, c.546G>T). Notably, the treatment of patient-derived fibroblasts carrying the c.-32-13T>G mutation with the U1+1 snRNA increased the amount of normal GAA mRNA by 1,8 fold and the GAA enzymatic activity by 70%. CONCLUSIONS we provide the proof-of-concept for the use of modified GAA-tailored U1 snRNAs, designed to potentiate the recognition of the GAA exon 2 5'ss, as therapeutic tools to correct the aberrant transcripts carrying variants that affect exon 2 splicing, including the common c.-32-13T>G variant.
Collapse
Affiliation(s)
- Paolo Peruzzo
- Regional Coordinator Centre for Rare Diseases, University Hospital of Udine, P. Le Santa Maria Della Misericordi 15, 33100, Udine, Italy
| | - Natascha Bergamin
- Regional Coordinator Centre for Rare Diseases, University Hospital of Udine, P. Le Santa Maria Della Misericordi 15, 33100, Udine, Italy
| | - Martina Bon
- Regional Coordinator Centre for Rare Diseases, University Hospital of Udine, P. Le Santa Maria Della Misericordi 15, 33100, Udine, Italy
| | - Sara Cappelli
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Area Science Park, Trieste, Italy
| | - Alessandra Longo
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Area Science Park, Trieste, Italy
| | - Elisa Goina
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Area Science Park, Trieste, Italy
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Area Science Park, Trieste, Italy
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Area Science Park, Trieste, Italy
| | - Andrea Dardis
- Regional Coordinator Centre for Rare Diseases, University Hospital of Udine, P. Le Santa Maria Della Misericordi 15, 33100, Udine, Italy.
| |
Collapse
|
4
|
Tzaban S, Stern O, Zisman E, Eisenberg G, Klein S, Frankenburg S, Lotem M. Alternative splicing of modulatory immune receptors in T lymphocytes: a newly identified and targetable mechanism for anticancer immunotherapy. Front Immunol 2025; 15:1490035. [PMID: 39845971 PMCID: PMC11752881 DOI: 10.3389/fimmu.2024.1490035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2024] [Accepted: 11/25/2024] [Indexed: 01/24/2025] Open
Abstract
Alternative splicing (AS) is a mechanism that generates translational diversity within a genome. Equally important is the dynamic adaptability of the splicing machinery, which can give preference to one isoform over others encoded by a single gene. These isoform preferences change in response to the cell's state and function. Particularly significant is the impact of physiological alternative splicing in T lymphocytes, where specific isoforms can enhance or reduce the cells' reactivity to stimuli. This process makes splicing isoforms defining features of cell states, exemplified by CD45 splice isoforms, which characterize the transition from naïve to memory states. Two developments have accelerated the use of AS dynamics for therapeutic interventions: advancements in long-read RNA sequencing and progress in nucleic acid chemical modifications. Improved oligonucleotide stability has enabled their use in directing splicing to specific sites or modifying sequences to enhance or silence particular splicing events. This review highlights immune regulatory splicing patterns with potential significance for enhancing anticancer immunotherapy.
Collapse
Affiliation(s)
- Shay Tzaban
- The Lautenberg Center for Immunology and Cancer Research, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ori Stern
- The Lautenberg Center for Immunology and Cancer Research, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Elad Zisman
- The Lautenberg Center for Immunology and Cancer Research, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Galit Eisenberg
- The Lautenberg Center for Immunology and Cancer Research, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- Center for Melanoma and Cancer Immunotherapy, Sharett Institute of Oncology, Jerusalem, Israel
| | - Shiri Klein
- The Lautenberg Center for Immunology and Cancer Research, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- Center for Melanoma and Cancer Immunotherapy, Sharett Institute of Oncology, Jerusalem, Israel
| | - Shoshana Frankenburg
- The Lautenberg Center for Immunology and Cancer Research, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Michal Lotem
- The Lautenberg Center for Immunology and Cancer Research, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- Center for Melanoma and Cancer Immunotherapy, Sharett Institute of Oncology, Jerusalem, Israel
- Hadassah Cancer Research Institute, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| |
Collapse
|
5
|
Parker MT, Fica SM, Simpson GG. RNA splicing: a split consensus reveals two major 5' splice site classes. Open Biol 2025; 15:240293. [PMID: 39809319 PMCID: PMC11732430 DOI: 10.1098/rsob.240293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2024] [Revised: 12/08/2024] [Accepted: 12/16/2024] [Indexed: 01/16/2025] Open
Abstract
The established consensus sequence for human 5' splice sites masks the presence of two major splice site classes defined by preferential base-pairing potentials with either U5 snRNA loop 1 or the U6 snRNA ACAGA box. The two 5' splice site classes are separable in genome sequences, sensitized by specific genotypes and associated with splicing complexity. The two classes reflect the commitment to 5' splice site usage occurring primarily during 5' splice site transfer to U6 snRNA. Separating the human 5' splice site consensus into its two major constituents can help us understand fundamental features of eukaryote genome architecture and splicing mechanisms and inform treatment design for diseases caused by genetic variation affecting splicing.
Collapse
|
6
|
Shen A, Hencel K, Parker M, Scott R, Skukan R, Adesina A, Metheringham C, Miska E, Nam Y, Haerty W, Simpson G, Akay A. U6 snRNA m6A modification is required for accurate and efficient splicing of C. elegans and human pre-mRNAs. Nucleic Acids Res 2024; 52:9139-9160. [PMID: 38808663 PMCID: PMC11347140 DOI: 10.1093/nar/gkae447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 05/08/2024] [Accepted: 05/28/2024] [Indexed: 05/30/2024] Open
Abstract
pre-mRNA splicing is a critical feature of eukaryotic gene expression. Both cis- and trans-splicing rely on accurately recognising splice site sequences by spliceosomal U snRNAs and associated proteins. Spliceosomal snRNAs carry multiple RNA modifications with the potential to affect different stages of pre-mRNA splicing. Here, we show that the conserved U6 snRNA m6A methyltransferase METT-10 is required for accurate and efficient cis- and trans-splicing of C. elegans pre-mRNAs. The absence of METT-10 in C. elegans and METTL16 in humans primarily leads to alternative splicing at 5' splice sites with an adenosine at +4 position. In addition, METT-10 is required for splicing of weak 3' cis- and trans-splice sites. We identified a significant overlap between METT-10 and the conserved splicing factor SNRNP27K in regulating 5' splice sites with +4A. Finally, we show that editing endogenous 5' splice site +4A positions to +4U restores splicing to wild-type positions in a mett-10 mutant background, supporting a direct role for U6 snRNA m6A modification in 5' splice site recognition. We conclude that the U6 snRNA m6A modification is important for accurate and efficient pre-mRNA splicing.
Collapse
Affiliation(s)
- Aykut Shen
- School of Biological Sciences, University of East Anglia, NR4 7TJ Norwich, UK
| | - Katarzyna Hencel
- School of Biological Sciences, University of East Anglia, NR4 7TJ Norwich, UK
| | - Matthew T Parker
- School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Robyn Scott
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Roberta Skukan
- School of Biological Sciences, University of East Anglia, NR4 7TJ Norwich, UK
| | | | | | - Eric A Miska
- Wellcome/CRUK Gurdon Institute, University of Cambridge, Tennis Court Rd, Cambridge CB2 1QN, UK
| | - Yunsun Nam
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Wilfried Haerty
- School of Biological Sciences, University of East Anglia, NR4 7TJ Norwich, UK
- Earlham Institute, Norwich Research Park, Norwich, UK
| | - Gordon G Simpson
- School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
- Cell & Molecular Sciences, James Hutton Institute, Invergowrie, DD2 5DA, UK
| | - Alper Akay
- School of Biological Sciences, University of East Anglia, NR4 7TJ Norwich, UK
| |
Collapse
|
7
|
Zhu Y, Vvedenskaya IO, Sze SH, Nickels BE, Kaplan CD. Quantitative analysis of transcription start site selection reveals control by DNA sequence, RNA polymerase II activity and NTP levels. Nat Struct Mol Biol 2024; 31:190-202. [PMID: 38177677 PMCID: PMC10928753 DOI: 10.1038/s41594-023-01171-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 11/03/2023] [Indexed: 01/06/2024]
Abstract
Transcription start site (TSS) selection is a key step in gene expression and occurs at many promoter positions over a wide range of efficiencies. Here we develop a massively parallel reporter assay to quantitatively dissect contributions of promoter sequence, nucleoside triphosphate substrate levels and RNA polymerase II (Pol II) activity to TSS selection by 'promoter scanning' in Saccharomyces cerevisiae (Pol II MAssively Systematic Transcript End Readout, 'Pol II MASTER'). Using Pol II MASTER, we measure the efficiency of Pol II initiation at 1,000,000 individual TSS sequences in a defined promoter context. Pol II MASTER confirms proposed critical qualities of S. cerevisiae TSS -8, -1 and +1 positions, quantitatively, in a controlled promoter context. Pol II MASTER extends quantitative analysis to surrounding sequences and determines that they tune initiation over a wide range of efficiencies. These results enabled the development of a predictive model for initiation efficiency based on sequence. We show that genetic perturbation of Pol II catalytic activity alters initiation efficiency mostly independently of TSS sequence, but selectively modulates preference for the initiating nucleotide. Intriguingly, we find that Pol II initiation efficiency is directly sensitive to guanosine-5'-triphosphate levels at the first five transcript positions and to cytosine-5'-triphosphate and uridine-5'-triphosphate levels at the second position genome wide. These results suggest individual nucleoside triphosphate levels can have transcript-specific effects on initiation, representing a cryptic layer of potential regulation at the level of Pol II biochemical properties. The results establish Pol II MASTER as a method for quantitative dissection of transcription initiation in eukaryotes.
Collapse
Affiliation(s)
- Yunye Zhu
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Irina O Vvedenskaya
- Department of Genetics and Waksman Institute, Rutgers University, Piscataway, NJ, USA
| | - Sing-Hoi Sze
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA
- Department of Computer Science and Engineering, Texas A&M University, College Station, TX, USA
| | - Bryce E Nickels
- Department of Genetics and Waksman Institute, Rutgers University, Piscataway, NJ, USA
| | - Craig D Kaplan
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
| |
Collapse
|
8
|
Suzuki Y, Nomura N, Yamada K, Yamada Y, Fukuda A, Hoshino K, Abe S, Kurosawa K, Inaba M, Mizuno S, Wakamatsu N, Hayashi S. Pathogenicity evaluation of variants of uncertain significance at exon-intron junction by splicing assay in patients with Mowat-Wilson syndrome. Eur J Med Genet 2023; 66:104882. [PMID: 37944854 DOI: 10.1016/j.ejmg.2023.104882] [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: 07/10/2023] [Revised: 10/20/2023] [Accepted: 11/02/2023] [Indexed: 11/12/2023]
Abstract
High-throughput sequencing has identified vast numbers of variants in genetic disorders. However, the significance of variants at the exon-intron junction remains controversial. Even though most cases of Mowat-Wilson syndrome (MOWS) are caused by heterozygous loss-of-function variants in ZEB2, the pathogenicity of variants at exon-intron junction is often indeterminable. We identified four intronic variants in 5/173 patients with clinical suspicion for MOWS, and evaluated their pathogenicity by in vitro analyses. The minigene analysis showed that c.73+2T>G caused most of the transcripts skipping exon 2, while c.916+6T>G led to partial skipping of exon 7. No splicing abnormalities were detected in both c.917-21T>C and c.3067+6A>T. The minigene analysis reproduced the splicing observed in the blood cells of the patient with c.73+2T>G. The degree of the exon skipping was concordant with the severity of MOWS; while the patient with c.73+2T>G was typical MOWS, the patient with c.916+6T>G showed milder phenotype which has been seldom reported. Our results demonstrate that mRNA splicing assays using the minigenes are valuable for determining the clinical significance of intronic variants in patients with not only MOWS but also other genetic diseases with splicing aberrations and may explain atypical or milder cases, such as the current patient.
Collapse
Affiliation(s)
- Yasuyo Suzuki
- Department of Genetics, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, Japan
| | - Noriko Nomura
- Department of Genetics, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, Japan
| | - Kenichiro Yamada
- Department of Genetics, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, Japan
| | - Yasukazu Yamada
- Department of Genetics, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, Japan
| | - Ayumi Fukuda
- Department of Pediatrics, Nihon University Itabashi Hospital, Itabashi, Tokyo, Japan
| | - Kyoko Hoshino
- Segawa Memorial Neurological Clinic for Children, Chiyoda, Tokyo, Japan
| | - Shinpei Abe
- Department of Pediatrics, Juntendo University, Faculty of Medicine, Bunkyo, Tokyo, Japan
| | - Kenji Kurosawa
- Division of Medical Genetics, Kanagawa Children's Medical Center, Yokohama, Kanagawa, Japan
| | - Mie Inaba
- Department of Pediatrics, Central Hospital, Aichi Developmental Disability Center, Kasugai, Aichi, Japan
| | - Seiji Mizuno
- Department of Pediatrics, Central Hospital, Aichi Developmental Disability Center, Kasugai, Aichi, Japan
| | - Nobuaki Wakamatsu
- Department of Genetics, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, Japan; Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Takamatsu, Kagawa, Japan
| | - Shin Hayashi
- Department of Genetics, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Aichi, Japan.
| |
Collapse
|
9
|
Farberov L, Weissglas-Volkov D, Shapira G, Zoabi Y, Schiff C, Kloeckener-Gruissem B, Neidhardt J, Shomron N. mRNA splicing is modulated by intronic microRNAs. iScience 2023; 26:107723. [PMID: 37692287 PMCID: PMC10492213 DOI: 10.1016/j.isci.2023.107723] [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: 09/15/2022] [Revised: 08/06/2023] [Accepted: 08/22/2023] [Indexed: 09/12/2023] Open
Abstract
Splicing of transcripts is catalyzed by the spliceosome, a mega-complex consisting of hundreds of proteins and five snRNAs, which employs direct interactions. When U1 snRNA forms high-affinity binding, namely more than eight base pairs, with the 5'SS, the result is usually a suppressing effect on the splicing activity. This likely occurs due to the inefficient unwinding of U1/5'SS base-pairing or other regulatory obstructions. Here, we show in vitro and in patient-derived cell lines that pre-microRNAs can modulate the splicing reaction by interacting with U1 snRNA. This leads to reduced binding affinity to the 5'SS, and hence promotes the inclusion of exons containing 5'SS, despite sequence-based high affinity to U1. Application of the mechanism resulted in correction of the splicing defect in the disease-causing VCAN gene from an individual with Wagner syndrome. This pre-miRNA/U1 interaction can regulate the expression of alternatively spliced exons, thus extending the scope of mechanisms regulating splicing.
Collapse
Affiliation(s)
- Luba Farberov
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Daphna Weissglas-Volkov
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Edmond J. Safra Center for Bioinformatics, Tel Aviv University, Tel Aviv, Israel
| | - Guy Shapira
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Edmond J. Safra Center for Bioinformatics, Tel Aviv University, Tel Aviv, Israel
| | - Yazeed Zoabi
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Edmond J. Safra Center for Bioinformatics, Tel Aviv University, Tel Aviv, Israel
| | - Chen Schiff
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Barbara Kloeckener-Gruissem
- Institute of Medical Molecular Genetics, University of Zurich, Zurich, Switzerland
- Department of Biology, ETHZ, Zurich, Switzerland
| | - John Neidhardt
- Human Genetics, Faculty of Medicine and Health Sciences, University of Oldenburg, Germany
- Research Center Neurosensory Science, University Oldenburg, Germany
| | - Noam Shomron
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Edmond J. Safra Center for Bioinformatics, Tel Aviv University, Tel Aviv, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
10
|
Beckel MS, Kaufman B, Yanovsky M, Chernomoretz A. Conserved and divergent signals in 5' splice site sequences across fungi, metazoa and plants. PLoS Comput Biol 2023; 19:e1011540. [PMID: 37831726 PMCID: PMC10599564 DOI: 10.1371/journal.pcbi.1011540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 10/25/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
In eukaryotic organisms the ensemble of 5' splice site sequences reflects the balance between natural nucleotide variability and minimal molecular constraints necessary to ensure splicing fidelity. This compromise shapes the underlying statistical patterns in the composition of donor splice site sequences. The scope of this study was to mine conserved and divergent signals in the composition of 5' splice site sequences. Because 5' donor sequences are a major cue for proper recognition of splice sites, we reasoned that statistical regularities in their composition could reflect the biological functionality and evolutionary history associated with splicing mechanisms. Results: We considered a regularized maximum entropy modeling framework to mine for non-trivial two-site correlations in donor sequence datasets corresponding to 30 different eukaryotes. For each analyzed species, we identified minimal sets of two-site coupling patterns that were able to replicate, at a given regularization level, the observed one-site and two-site frequencies in donor sequences. By performing a systematic and comparative analysis of 5'splice sites we showed that lineage information could be traced from joint di-nucleotide probabilities. We were able to identify characteristic two-site coupling patterns for plants and animals, and propose that they may echo differences in splicing regulation previously reported between these groups.
Collapse
Affiliation(s)
- Maximiliano S. Beckel
- Fundación Instituto Leloir, Buenos Aires, Argentina
- Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Bruno Kaufman
- Fundación Instituto Leloir, Buenos Aires, Argentina
- Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Marcelo Yanovsky
- Fundación Instituto Leloir, Buenos Aires, Argentina
- Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Ariel Chernomoretz
- Fundación Instituto Leloir, Buenos Aires, Argentina
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto de Física Interdisciplinaria y Aplicada (INFINA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| |
Collapse
|
11
|
Gonçalves M, Santos JI, Coutinho MF, Matos L, Alves S. Development of Engineered-U1 snRNA Therapies: Current Status. Int J Mol Sci 2023; 24:14617. [PMID: 37834063 PMCID: PMC10572768 DOI: 10.3390/ijms241914617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/22/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
Splicing of pre-mRNA is a crucial regulatory stage in the pathway of gene expression. The majority of human genes that encode proteins undergo alternative pre-mRNA splicing and mutations that affect splicing are more prevalent than previously thought. Targeting aberrant RNA(s) may thus provide an opportunity to correct faulty splicing and potentially treat numerous genetic disorders. To that purpose, the use of engineered U1 snRNA (either modified U1 snRNAs or exon-specific U1s-ExSpeU1s) has been applied as a potentially therapeutic strategy to correct splicing mutations, particularly those affecting the 5' splice-site (5'ss). Here we review and summarize a vast panoply of studies that used either modified U1 snRNAs or ExSpeU1s to mediate gene therapeutic correction of splicing defects underlying a considerable number of genetic diseases. We also focus on the pre-clinical validation of these therapeutic approaches both in vitro and in vivo, and summarize the main obstacles that need to be overcome to allow for their successful translation to clinic practice in the future.
Collapse
Affiliation(s)
- Mariana Gonçalves
- Research and Development Unit, Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, INSA I.P., Rua Alexandre Herculano, 321, 4000-055 Porto, Portugal; (M.G.); (J.I.S.); (M.F.C.); (L.M.)
- Center for the Study of Animal Science, Institute of Sciences, Technologies and Agro-Environment, CECA-ICETA, University of Porto, Praça Gomes Teixeira, Apartado 55142, 4051-401 Porto, Portugal
- Associate Laboratory for Animal and Veterinary Sciences, AL4AnimalS, Faculty of Veterinary Medicine, University of Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences, CITAB, Inov4Agro, University of Trás-os-Montes and Alto Douro, 5000-801 Vila Real, Portugal
| | - Juliana Inês Santos
- Research and Development Unit, Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, INSA I.P., Rua Alexandre Herculano, 321, 4000-055 Porto, Portugal; (M.G.); (J.I.S.); (M.F.C.); (L.M.)
- Center for the Study of Animal Science, Institute of Sciences, Technologies and Agro-Environment, CECA-ICETA, University of Porto, Praça Gomes Teixeira, Apartado 55142, 4051-401 Porto, Portugal
- Associate Laboratory for Animal and Veterinary Sciences, AL4AnimalS, Faculty of Veterinary Medicine, University of Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
- Biology Department, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal
| | - Maria Francisca Coutinho
- Research and Development Unit, Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, INSA I.P., Rua Alexandre Herculano, 321, 4000-055 Porto, Portugal; (M.G.); (J.I.S.); (M.F.C.); (L.M.)
- Center for the Study of Animal Science, Institute of Sciences, Technologies and Agro-Environment, CECA-ICETA, University of Porto, Praça Gomes Teixeira, Apartado 55142, 4051-401 Porto, Portugal
- Associate Laboratory for Animal and Veterinary Sciences, AL4AnimalS, Faculty of Veterinary Medicine, University of Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Liliana Matos
- Research and Development Unit, Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, INSA I.P., Rua Alexandre Herculano, 321, 4000-055 Porto, Portugal; (M.G.); (J.I.S.); (M.F.C.); (L.M.)
- Center for the Study of Animal Science, Institute of Sciences, Technologies and Agro-Environment, CECA-ICETA, University of Porto, Praça Gomes Teixeira, Apartado 55142, 4051-401 Porto, Portugal
- Associate Laboratory for Animal and Veterinary Sciences, AL4AnimalS, Faculty of Veterinary Medicine, University of Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Sandra Alves
- Research and Development Unit, Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, INSA I.P., Rua Alexandre Herculano, 321, 4000-055 Porto, Portugal; (M.G.); (J.I.S.); (M.F.C.); (L.M.)
- Center for the Study of Animal Science, Institute of Sciences, Technologies and Agro-Environment, CECA-ICETA, University of Porto, Praça Gomes Teixeira, Apartado 55142, 4051-401 Porto, Portugal
- Associate Laboratory for Animal and Veterinary Sciences, AL4AnimalS, Faculty of Veterinary Medicine, University of Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| |
Collapse
|
12
|
Bouvet D, Blondel A, de Sainte Agathe JM, Leroy G, Saint-Martin C, Bellanné-Chantelot C. Evaluation in Monogenic Diabetes of the Impact of GCK, HNF1A, and HNF4A Variants on Splicing through the Combined Use of In Silico Tools and Minigene Assays. Hum Mutat 2023; 2023:6661013. [PMID: 40225161 PMCID: PMC11919142 DOI: 10.1155/2023/6661013] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 08/08/2023] [Accepted: 08/17/2023] [Indexed: 04/15/2025]
Abstract
Variants in GCK, HNF1A, and HNF4A genes are the three main causes of monogenic diabetes. Determining the molecular etiology is essential for patients with monogenic diabetes to benefit from the most appropriate treatment. The increasing number of variants of unknown significance (VUS) is a major issue in genetic diagnosis, and assessing the impact of variants on RNA splicing is challenging, particularly for genes expressed in tissues not easily accessible as in monogenic diabetes. The in vitro functional splicing assay based on a minigene construct is an appropriate approach. Here, we performed in silico analysis using SpliceAI and SPiP and prioritized 36 spliceogenic variants in GCK, HNF1A, and HNF4A. Predictions were secondarily compared with Pangolin and AbSplice-DNA bioinformatics tools which include tissue-specific annotations. We assessed the effect of selected variants on RNA splicing using minigene assays. These assays validated splicing defects for 33 out of 36 spliceogenic variants consisting of exon skipping (15%), exonic deletions (18%), intronic retentions (24%), and complex splicing patterns (42%). This provided additional evidence to reclassify 23 out of 31 (74%) VUS including missense, synonymous, and intronic noncanonical splice site variants as likely pathogenic variants. Comparison of in silico analysis with minigene results showed the robustness of bioinformatics tools to prioritize spliceogenic variants, but revealed inconsistencies in the location of cryptic splice sites underlying the importance of confirming predicted splicing alterations with functional splicing assays. Our study underlines the feasibility and the benefits of implementing minigene-splicing assays in the genetic testing of monogenic diabetes after a prior in-depth in silico analysis.
Collapse
Affiliation(s)
- Delphine Bouvet
- Department of Medical Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | - Amélie Blondel
- Department of Medical Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | | | - Gwendoline Leroy
- Department of Medical Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | - Cécile Saint-Martin
- Department of Medical Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | | |
Collapse
|
13
|
Parker MT, Soanes BK, Kusakina J, Larrieu A, Knop K, Joy N, Breidenbach F, Sherwood AV, Barton GJ, Fica SM, Davies BH, Simpson GG. m 6A modification of U6 snRNA modulates usage of two major classes of pre-mRNA 5' splice site. eLife 2022; 11:e78808. [PMID: 36409063 PMCID: PMC9803359 DOI: 10.7554/elife.78808] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 11/20/2022] [Indexed: 11/23/2022] Open
Abstract
Alternative splicing of messenger RNAs is associated with the evolution of developmentally complex eukaryotes. Splicing is mediated by the spliceosome, and docking of the pre-mRNA 5' splice site into the spliceosome active site depends upon pairing with the conserved ACAGA sequence of U6 snRNA. In some species, including humans, the central adenosine of the ACAGA box is modified by N6 methylation, but the role of this m6A modification is poorly understood. Here, we show that m6A modified U6 snRNA determines the accuracy and efficiency of splicing. We reveal that the conserved methyltransferase, FIONA1, is required for Arabidopsis U6 snRNA m6A modification. Arabidopsis fio1 mutants show disrupted patterns of splicing that can be explained by the sequence composition of 5' splice sites and cooperative roles for U5 and U6 snRNA in splice site selection. U6 snRNA m6A influences 3' splice site usage. We generalise these findings to reveal two major classes of 5' splice site in diverse eukaryotes, which display anti-correlated interaction potential with U5 snRNA loop 1 and the U6 snRNA ACAGA box. We conclude that U6 snRNA m6A modification contributes to the selection of degenerate 5' splice sites crucial to alternative splicing.
Collapse
Affiliation(s)
- Matthew T Parker
- School of Life Sciences, University of DundeeDundeeUnited Kingdom
| | - Beth K Soanes
- Centre for Plant Sciences, School of Biology, Faculty of Biological Sciences, University of LeedsLeedsUnited Kingdom
| | - Jelena Kusakina
- Centre for Plant Sciences, School of Biology, Faculty of Biological Sciences, University of LeedsLeedsUnited Kingdom
| | - Antoine Larrieu
- Centre for Plant Sciences, School of Biology, Faculty of Biological Sciences, University of LeedsLeedsUnited Kingdom
| | - Katarzyna Knop
- School of Life Sciences, University of DundeeDundeeUnited Kingdom
| | - Nisha Joy
- School of Life Sciences, University of DundeeDundeeUnited Kingdom
| | - Friedrich Breidenbach
- School of Life Sciences, University of DundeeDundeeUnited Kingdom
- RNA Biology and Molecular Physiology, Faculty of Biology, Bielefeld UniversityBielefeldGermany
| | - Anna V Sherwood
- School of Life Sciences, University of DundeeDundeeUnited Kingdom
| | | | - Sebastian M Fica
- Department of Biochemistry, University of OxfordOxfordUnited Kingdom
| | - Brendan H Davies
- Centre for Plant Sciences, School of Biology, Faculty of Biological Sciences, University of LeedsLeedsUnited Kingdom
| | - Gordon G Simpson
- School of Life Sciences, University of DundeeDundeeUnited Kingdom
- Cell & Molecular Sciences, James Hutton InstituteInvergowrieUnited Kingdom
| |
Collapse
|
14
|
Cormier MJ, Pedersen BS, Bayrak-Toydemir P, Quinlan AR. Combining genetic constraint with predictions of alternative splicing to prioritize deleterious splicing in rare disease studies. BMC Bioinformatics 2022; 23:482. [PMID: 36376793 PMCID: PMC9664736 DOI: 10.1186/s12859-022-05041-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Despite numerous molecular and computational advances, roughly half of patients with a rare disease remain undiagnosed after exome or genome sequencing. A particularly challenging barrier to diagnosis is identifying variants that cause deleterious alternative splicing at intronic or exonic loci outside of canonical donor or acceptor splice sites. RESULTS Several existing tools predict the likelihood that a genetic variant causes alternative splicing. We sought to extend such methods by developing a new metric that aids in discerning whether a genetic variant leads to deleterious alternative splicing. Our metric combines genetic variation in the Genome Aggregate Database with alternative splicing predictions from SpliceAI to compare observed and expected levels of splice-altering genetic variation. We infer genic regions with significantly less splice-altering variation than expected to be constrained. The resulting model of regional splicing constraint captures differential splicing constraint across gene and exon categories, and the most constrained genic regions are enriched for pathogenic splice-altering variants. Building from this model, we developed ConSpliceML. This ensemble machine learning approach combines regional splicing constraint with multiple per-nucleotide alternative splicing scores to guide the prediction of deleterious splicing variants in protein-coding genes. ConSpliceML more accurately distinguishes deleterious and benign splicing variants than state-of-the-art splicing prediction methods, especially in "cryptic" splicing regions beyond canonical donor or acceptor splice sites. CONCLUSION Integrating a model of genetic constraint with annotations from existing alternative splicing tools allows ConSpliceML to prioritize potentially deleterious splice-altering variants in studies of rare human diseases.
Collapse
Affiliation(s)
- Michael J Cormier
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA
- Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT, USA
| | - Brent S Pedersen
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA
- Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT, USA
| | | | - Aaron R Quinlan
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA.
- Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT, USA.
- Department of Biomedical Informatics, University of Utah, Salt Lake City, UT, USA.
| |
Collapse
|
15
|
Abstract
One core goal of genetics is to systematically understand the mapping between the DNA sequence of an organism (genotype) and its measurable characteristics (phenotype). Understanding this mapping is often challenging because of interactions between mutations, where the result of combining several different mutations can be very different than the sum of their individual effects. Here we provide a statistical framework for modeling complex genetic interactions of this type. The key idea is to ask how fast the effects of mutations change when introducing the same mutation in increasingly distant genetic backgrounds. We then propose a model for phenotypic prediction that takes into account this tendency for the effects of mutations to be more similar in nearby genetic backgrounds. Contemporary high-throughput mutagenesis experiments are providing an increasingly detailed view of the complex patterns of genetic interaction that occur between multiple mutations within a single protein or regulatory element. By simultaneously measuring the effects of thousands of combinations of mutations, these experiments have revealed that the genotype–phenotype relationship typically reflects not only genetic interactions between pairs of sites but also higher-order interactions among larger numbers of sites. However, modeling and understanding these higher-order interactions remains challenging. Here we present a method for reconstructing sequence-to-function mappings from partially observed data that can accommodate all orders of genetic interaction. The main idea is to make predictions for unobserved genotypes that match the type and extent of epistasis found in the observed data. This information on the type and extent of epistasis can be extracted by considering how phenotypic correlations change as a function of mutational distance, which is equivalent to estimating the fraction of phenotypic variance due to each order of genetic interaction (additive, pairwise, three-way, etc.). Using these estimated variance components, we then define an empirical Bayes prior that in expectation matches the observed pattern of epistasis and reconstruct the genotype–phenotype mapping by conducting Gaussian process regression under this prior. To demonstrate the power of this approach, we present an application to the antibody-binding domain GB1 and also provide a detailed exploration of a dataset consisting of high-throughput measurements for the splicing efficiency of human pre-mRNA 5′ splice sites, for which we also validate our model predictions via additional low-throughput experiments.
Collapse
|
16
|
Hansen SR, White DS, Scalf M, Corrêa IR, Smith LM, Hoskins AA. Multi-step recognition of potential 5' splice sites by the Saccharomyces cerevisiae U1 snRNP. eLife 2022; 11:70534. [PMID: 35959885 PMCID: PMC9436412 DOI: 10.7554/elife.70534] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 08/11/2022] [Indexed: 11/13/2022] Open
Abstract
In eukaryotes, splice sites define the introns of pre-mRNAs and must be recognized and excised with nucleotide precision by the spliceosome to make the correct mRNA product. In one of the earliest steps of spliceosome assembly, the U1 small nuclear ribonucleoprotein (snRNP) recognizes the 5' splice site (5' SS) through a combination of base pairing, protein-RNA contacts, and interactions with other splicing factors. Previous studies investigating the mechanisms of 5' SS recognition have largely been done in vivo or in cellular extracts where the U1/5' SS interaction is difficult to deconvolute from the effects of trans-acting factors or RNA structure. In this work we used colocalization single-molecule spectroscopy (CoSMoS) to elucidate the pathway of 5' SS selection by purified yeast U1 snRNP. We determined that U1 reversibly selects 5' SS in a sequence-dependent, two-step mechanism. A kinetic selection scheme enforces pairing at particular positions rather than overall duplex stability to achieve long-lived U1 binding. Our results provide a kinetic basis for how U1 may rapidly surveil nascent transcripts for 5' SS and preferentially accumulate at these sequences rather than on close cognates.
Collapse
Affiliation(s)
- Sarah R Hansen
- Department of Biochemistry, University of Wisconsin-Madison, Madison, United States
| | - David S White
- Department of Biochemistry, University of Wisconsin-Madison, Madison, United States
| | - Mark Scalf
- Department of Chemistry, University of Wisconsin-Madison, Madison, United States
| | | | - Lloyd M Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, United States
| | - Aaron A Hoskins
- Department of Biochemistry, University of Wisconsin-Madison, Madison, United States
| |
Collapse
|
17
|
Anderson SL, Fasih-Ahmad F, Evans AJ, Rubin BY. Carnosol, a diterpene present in rosemary, increases ELP1 levels in familial Dysautonomia (FD) patient-derived cells and healthy adults: a possible therapy for FD. Hum Mol Genet 2022; 31:3521-3538. [PMID: 35708500 DOI: 10.1093/hmg/ddac133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/12/2022] [Accepted: 06/01/2022] [Indexed: 11/13/2022] Open
Abstract
Recent research on Familial Dysautonomia (FD) has focused on the development of therapeutics that facilitate the production of the correctly spliced, exon 20-containing, transcript in cells and individuals bearing the splice-altering, FD-causing, mutation in the ELP1 gene. We report here the ability of carnosol, a diterpene present in plant species of the Lamiaceae family, including rosemary, to enhance the cellular presence of the correctly spliced ELP1 transcript in FD patient-derived fibroblasts by upregulating transcription of the ELP1 gene and correcting the aberrant splicing of the ELP1 transcript. Carnosol treatment also elevates the level of the RBM24 and RBM38 proteins., two multifunctional RNA binding proteins. Transfection-mediated expression of either of these RBMs facilitates the inclusion of exon 20 sequence into the transcript generated from a minigene bearing ELP1 genomic sequence containing the FD-causing mutation. Suppression of the carnosol-mediated induction of either of these RBMs, using targeting siRNAs, limited the carnosol-mediated inclusion of the ELP1 exon 20 sequence. Carnosol treatment of FD patient PBMCs facilitates the inclusion of exon 20 into the ELP1 transcript. Increased levels of the ELP1 and RBM38 transcripts and the alternative splicing of the SIRT2 transcript, a sentinel for exon 20 inclusion in the FD-derived ELP1 transcript, are observed in RNA isolated from whole blood of healthy adults following the ingestion of carnosol-containing rosemary extract. These findings and the excellent safety profile of rosemary together justify an expedited clinical study of the impact of carnosol on the FD patient population.
Collapse
Affiliation(s)
- Sylvia L Anderson
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
| | - Faaria Fasih-Ahmad
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
| | - Anthony J Evans
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
| | - Berish Y Rubin
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
| |
Collapse
|
18
|
Lee MYH, Khoury G, Olshansky M, Sonza S, Carter GP, McMahon J, Stinear TP, Turner SJ, Lewin SR, Purcell DFJ. Detection of Chimeric Cellular: HIV mRNAs Generated Through Aberrant Splicing in HIV-1 Latently Infected Resting CD4+ T Cells. Front Cell Infect Microbiol 2022; 12:855290. [PMID: 35573784 PMCID: PMC9096486 DOI: 10.3389/fcimb.2022.855290] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 03/25/2022] [Indexed: 11/13/2022] Open
Abstract
Latent HIV-1 provirus in infected individuals on suppressive therapy does not always remain transcriptionally silent. Both HIV-1 LTR and human gene promoter derived transcriptional events can contribute HIV-1 sequences to the mRNA produced in the cell. In addition, chimeric cellular:HIV mRNA can arise through readthrough transcription and aberrant splicing. Using target enrichment coupled to the Illumina Mi-Seq and PacBio RS II platforms, we show that 3’ LTR activation is frequent in latently infected cells from both the CCL19-induced primary cell model of HIV-1 latency as well as ex vivo samples. In both systems of latent HIV-1 infection, we detected several chimeric species that were generated via activation of a cryptic splice donor site in the 5’ LTR of HIV-1. Aberrant splicing involving the major HIV-1 splice donor sites, SD1 and SD4 disrupts post-transcriptional processing of the gene in which HIV-1 is integrated. In the primary cell model of HIV-1 latency, Tat-encoding sequences are incorporated into the chimeric mRNA transcripts through the use of SD4. Our study unravels clues to the characteristics of HIV-1 integrants that promote formation of chimeric cellular:HIV mRNA and improves the understanding of the HIV-1 RNA footprint in latently infected cells.
Collapse
Affiliation(s)
- Michelle Y-H Lee
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Georges Khoury
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Moshe Olshansky
- Department of Microbiology, Biomedical Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Secondo Sonza
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Glen P. Carter
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
- Doherty Applied Microbial Genomics, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - James McMahon
- Department of Infectious Diseases, Monash University and Alfred Hospital, Melbourne, VIC, Australia
| | - Timothy P. Stinear
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
- Doherty Applied Microbial Genomics, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Stephen J. Turner
- Department of Microbiology, Biomedical Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Sharon R. Lewin
- Department of Infectious Diseases, Monash University and Alfred Hospital, Melbourne, VIC, Australia
- Department of Infectious Diseases, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
- Victorian Infectious Diseases Service, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Damian F. J. Purcell
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
- *Correspondence: Damian F. J. Purcell,
| |
Collapse
|
19
|
Tammer L, Hameiri O, Keydar I, Roy VR, Ashkenazy-Titelman A, Custódio N, Sason I, Shayevitch R, Rodríguez-Vaello V, Rino J, Lev Maor G, Leader Y, Khair D, Aiden EL, Elkon R, Irimia M, Sharan R, Shav-Tal Y, Carmo-Fonseca M, Ast G. Gene architecture directs splicing outcome in separate nuclear spatial regions. Mol Cell 2022; 82:1021-1034.e8. [PMID: 35182478 DOI: 10.1016/j.molcel.2022.02.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 01/31/2022] [Accepted: 01/31/2022] [Indexed: 12/13/2022]
Abstract
How the splicing machinery defines exons or introns as the spliced unit has remained a puzzle for 30 years. Here, we demonstrate that peripheral and central regions of the nucleus harbor genes with two distinct exon-intron GC content architectures that differ in the splicing outcome. Genes with low GC content exons, flanked by long introns with lower GC content, are localized in the periphery, and the exons are defined as the spliced unit. Alternative splicing of these genes results in exon skipping. In contrast, the nuclear center contains genes with a high GC content in the exons and short flanking introns. Most splicing of these genes occurs via intron definition, and aberrant splicing leads to intron retention. We demonstrate that the nuclear periphery and center generate different environments for the regulation of alternative splicing and that two sets of splicing factors form discrete regulatory subnetworks for the two gene architectures. Our study connects 3D genome organization and splicing, thus demonstrating that exon and intron definition modes of splicing occur in different nuclear regions.
Collapse
Affiliation(s)
- Luna Tammer
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Ofir Hameiri
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Ifat Keydar
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Vanessa Rachel Roy
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Asaf Ashkenazy-Titelman
- The Mina & Everard Goodman Faculty of Life Sciences and the Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Noélia Custódio
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Itay Sason
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ronna Shayevitch
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Victoria Rodríguez-Vaello
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Spain, ICREA, Barcelona, Spain
| | - José Rino
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Galit Lev Maor
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Yodfat Leader
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Doha Khair
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Erez Lieberman Aiden
- The Center for Genome Architecture, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ran Elkon
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Manuel Irimia
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Spain, ICREA, Barcelona, Spain
| | - Roded Sharan
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yaron Shav-Tal
- The Mina & Everard Goodman Faculty of Life Sciences and the Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Maria Carmo-Fonseca
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Gil Ast
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel.
| |
Collapse
|
20
|
Functional assays of non-canonical splice-site variants in inherited retinal dystrophies genes. Sci Rep 2022; 12:68. [PMID: 34996991 PMCID: PMC8742059 DOI: 10.1038/s41598-021-03925-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 12/10/2021] [Indexed: 11/17/2022] Open
Abstract
Inherited retinal dystrophies are a group of disorders characterized by the progressive degeneration of photoreceptors leading to loss of the visual function and eventually to legal blindness. Although next generation sequencing (NGS) has revolutionized the molecular diagnosis of these diseases, the pathogenicity of some mutations casts doubts. After the screening of 208 patients with a panel of 117 genes, we obtained 383 variants that were analysed in silico with bioinformatic prediction programs. Based on the results of these tools, we selected 15 variants for their functional assessment. Therefore, we carried out minigene assays to unveil whether they could affect the splicing of the corresponding gene. As a whole, seven variants were found to induce aberrant splicing in the following genes: BEST1, CACNA2D4, PRCD, RIMS1, FSCN2, MERTK and MAK. This study shows the efficacy of a workflow, based on the association of the Minimum Allele Frequency, family co-segregation, in silico predictions and in vitro assays to determine the effect of potential splice site variants identified by DNA-based NGS. These findings improve the molecular diagnosis of inherited retinal dystrophies and will allow some patients to benefit from the upcoming gene-based therapeutic strategies.
Collapse
|
21
|
Kim D, Lee J, Cho CH, Kim EJ, Bhattacharya D, Yoon HS. Group II intron and repeat-rich red algal mitochondrial genomes demonstrate the dynamic recent history of autocatalytic RNAs. BMC Biol 2022; 20:2. [PMID: 34996446 PMCID: PMC8742464 DOI: 10.1186/s12915-021-01200-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 11/29/2021] [Indexed: 11/10/2022] Open
Abstract
Background Group II introns are mobile genetic elements that can insert at specific target sequences, however, their origins are often challenging to reconstruct because of rapid sequence decay following invasion and spread into different sites. To advance understanding of group II intron spread, we studied the intron-rich mitochondrial genome (mitogenome) in the unicellular red alga, Porphyridium. Results Analysis of mitogenomes in three closely related species in this genus revealed they were 3–6-fold larger in size (56–132 kbp) than in other red algae, that have genomes of size 21–43 kbp. This discrepancy is explained by two factors, group II intron invasion and expansion of repeated sequences in large intergenic regions. Phylogenetic analysis demonstrates that many mitogenome group II intron families are specific to Porphyridium, whereas others are closely related to sequences in fungi and in the red alga-derived plastids of stramenopiles. Network analysis of intron-encoded proteins (IEPs) shows a clear link between plastid and mitochondrial IEPs in distantly related species, with both groups associated with prokaryotic sequences. Conclusion Our analysis of group II introns in Porphyridium mitogenomes demonstrates the dynamic nature of group II intron evolution, strongly supports the lateral movement of group II introns among diverse eukaryotes, and reveals their ability to proliferate, once integrated in mitochondrial DNA. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01200-3.
Collapse
Affiliation(s)
- Dongseok Kim
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, South Korea
| | - JunMo Lee
- Department of Oceanography, Kyungpook National University, Daegu, 41566, South Korea
| | - Chung Hyun Cho
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Eun Jeung Kim
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Debashish Bhattacharya
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, South Korea.
| |
Collapse
|
22
|
Abstract
Mutations affecting constitutive splice donor sites (5'ss) are among the most frequent genetic defects that disrupt the normal splicing process. Pre-mRNA splicing requires the correct identification of a number of cis-acting elements in an ordered fashion. By disrupting the complementarity of the 5'ss with the endogenous small nuclear RNA U1 (U1 snRNA), the key component of the spliceosomal U1 ribonucleoprotein, 5'ss mutations may result in exon skipping, intron retention or activation of cryptic splice sites. Engineered modification of the U1 snRNA seemed to be a logical method to overcome the effect of those mutations. In fact, over the last years, a number of in vitro studies on the use of those modified U1 snRNAs to correct a variety of splicing defects have demonstrated the feasibility of this approach. Furthermore, recent reports on its applicability in vivo are adding up to the principle that engineered modification of U1 snRNAs represents a valuable approach and prompting further studies to demonstrate the clinical translatability of this strategy.Here, we outline the design and generation of U1 snRNAs with different degrees of complementarity to mutated 5'ss. Using the HGSNAT gene as an example, we describe the methods for a proper evaluation of their efficacy in vitro, taking advantage of our experience to share a number of tips on how to design U1 snRNA molecules for splicing rescue.
Collapse
Affiliation(s)
- Liliana Matos
- Department of Human Genetics, Research and Development Unit, National Health Institute Doutor Ricardo Jorge, Porto, Portugal
- Center for the Study of Animal Science (CECA) - Institute of Sciences, Technologies and Agroenvironment (ICETA), University of Porto, Porto, Portugal
| | - Juliana I Santos
- Department of Human Genetics, Research and Development Unit, National Health Institute Doutor Ricardo Jorge, Porto, Portugal
- Biology Department, Faculty of Sciences, University of Porto, Porto, Portugal
| | - Mª Francisca Coutinho
- Department of Human Genetics, Research and Development Unit, National Health Institute Doutor Ricardo Jorge, Porto, Portugal
- Center for the Study of Animal Science (CECA) - Institute of Sciences, Technologies and Agroenvironment (ICETA), University of Porto, Porto, Portugal
| | - Sandra Alves
- Department of Human Genetics, Research and Development Unit, National Health Institute Doutor Ricardo Jorge, Porto, Portugal.
- Center for the Study of Animal Science (CECA) - Institute of Sciences, Technologies and Agroenvironment (ICETA), University of Porto, Porto, Portugal.
| |
Collapse
|
23
|
Jüschke C, Klopstock T, Catarino CB, Owczarek-Lipska M, Wissinger B, Neidhardt J. Autosomal dominant optic atrophy: A novel treatment for OPA1 splice defects using U1 snRNA adaption. MOLECULAR THERAPY. NUCLEIC ACIDS 2021; 26:1186-1197. [PMID: 34853716 PMCID: PMC8604756 DOI: 10.1016/j.omtn.2021.10.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 06/03/2021] [Accepted: 10/19/2021] [Indexed: 11/15/2022]
Abstract
Autosomal dominant optic atrophy (ADOA) is frequently caused by mutations in the optic atrophy 1 (OPA1) gene, with haploinsufficiency being the major genetic pathomechanism. Almost 30% of the OPA1-associated cases suffer from splice defects. We identified a novel OPA1 mutation, c.1065+5G>A, in patients with ADOA. In patient-derived fibroblasts, the mutation led to skipping of OPA1 exon 10, reducing the OPA1 protein expression by approximately 50%. We developed a molecular treatment to correct the splice defect in OPA1 using engineered U1 splice factors retargeted to different locations in OPA1 exon 10 or intron 10. The strongest therapeutic effect was detected when U1 binding was engineered to bind to intron 10 at position +18, a position predicted by bioinformatics to be a promising binding site. We were able to significantly silence the effect of the mutation (skipping of exon 10) and simultaneously increase the expression level of normal transcripts. Retargeting U1 to the canonical splice donor site did not lead to a detectable splice correction. This proof-of-concept study indicates for the first time the feasibility of splice mutation correction as a treatment option for ADOA. Increasing the amount of correctly spliced OPA1 transcripts may suffice to overcome the haploinsufficiency.
Collapse
Affiliation(s)
- Christoph Jüschke
- Human Genetics, Faculty of Medicine and Health Sciences, University of Oldenburg, 26129 Oldenburg, Germany
| | - Thomas Klopstock
- Friedrich-Baur Institute, Department of Neurology, University Hospital, LMU Munich, University of Munich, 80336 Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Claudia B. Catarino
- Friedrich-Baur Institute, Department of Neurology, University Hospital, LMU Munich, University of Munich, 80336 Munich, Germany
| | - Marta Owczarek-Lipska
- Human Genetics, Faculty of Medicine and Health Sciences, University of Oldenburg, 26129 Oldenburg, Germany
- Research Center Neurosensory Science, University of Oldenburg, 26129 Oldenburg, Germany
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, 72076 Tübingen, Germany
| | - John Neidhardt
- Human Genetics, Faculty of Medicine and Health Sciences, University of Oldenburg, 26129 Oldenburg, Germany
- Research Center Neurosensory Science, University of Oldenburg, 26129 Oldenburg, Germany
- Joint Research Training Group of the Faculty of Medicine and Health Sciences, University of Oldenburg, 26129 Oldenburg, Germany and University Medical Center Groningen, 9700 RB Groningen, the Netherlands
- Correspondence: John Neidhardt, Human Genetics, Faculty of Medicine and Health Sciences, University of Oldenburg, Ammerländer Heerstrasse 114-118, 26129 Oldenburg, Germany.
| |
Collapse
|
24
|
Field-theoretic density estimation for biological sequence space with applications to 5' splice site diversity and aneuploidy in cancer. Proc Natl Acad Sci U S A 2021; 118:2025782118. [PMID: 34599093 DOI: 10.1073/pnas.2025782118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2021] [Indexed: 12/17/2022] Open
Abstract
Density estimation in sequence space is a fundamental problem in machine learning that is also of great importance in computational biology. Due to the discrete nature and large dimensionality of sequence space, how best to estimate such probability distributions from a sample of observed sequences remains unclear. One common strategy for addressing this problem is to estimate the probability distribution using maximum entropy (i.e., calculating point estimates for some set of correlations based on the observed sequences and predicting the probability distribution that is as uniform as possible while still matching these point estimates). Building on recent advances in Bayesian field-theoretic density estimation, we present a generalization of this maximum entropy approach that provides greater expressivity in regions of sequence space where data are plentiful while still maintaining a conservative maximum entropy character in regions of sequence space where data are sparse or absent. In particular, we define a family of priors for probability distributions over sequence space with a single hyperparameter that controls the expected magnitude of higher-order correlations. This family of priors then results in a corresponding one-dimensional family of maximum a posteriori estimates that interpolate smoothly between the maximum entropy estimate and the observed sample frequencies. To demonstrate the power of this method, we use it to explore the high-dimensional geometry of the distribution of 5' splice sites found in the human genome and to understand patterns of chromosomal abnormalities across human cancers.
Collapse
|
25
|
Top O, Milferstaedt SWL, van Gessel N, Hoernstein SNW, Özdemir B, Decker EL, Reski R. Expression of a human cDNA in moss results in spliced mRNAs and fragmentary protein isoforms. Commun Biol 2021; 4:964. [PMID: 34385580 PMCID: PMC8361020 DOI: 10.1038/s42003-021-02486-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 07/26/2021] [Indexed: 12/18/2022] Open
Abstract
Production of biopharmaceuticals relies on the expression of mammalian cDNAs in host organisms. Here we show that the expression of a human cDNA in the moss Physcomitrium patens generates the expected full-length and four additional transcripts due to unexpected splicing. This mRNA splicing results in non-functional protein isoforms, cellular misallocation of the proteins and low product yields. We integrated these results together with the results of our analysis of all 32,926 protein-encoding Physcomitrella genes and their 87,533 annotated transcripts in a web application, physCO, for automatized optimization. A thus optimized cDNA results in about twelve times more protein, which correctly localizes to the ER. An analysis of codon preferences of different production hosts suggests that similar effects occur also in non-plant hosts. We anticipate that the use of our methodology will prevent so far undetected mRNA heterosplicing resulting in maximized functional protein amounts for basic biology and biotechnology.
Collapse
Affiliation(s)
- Oguz Top
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany
- Plant Molecular Cell Biology, Department Biology I, LMU Biocenter, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Stella W L Milferstaedt
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Cluster of Excellence livMatS @ FIT - Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Freiburg, Germany
| | - Nico van Gessel
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | | | - Bugra Özdemir
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Eva L Decker
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Ralf Reski
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, Germany.
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany.
- Cluster of Excellence livMatS @ FIT - Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Freiburg, Germany.
- CIBSS - Centre for Integrative Biological Signalling Studies, Freiburg, Germany.
| |
Collapse
|
26
|
Ajiro M, Awaya T, Kim YJ, Iida K, Denawa M, Tanaka N, Kurosawa R, Matsushima S, Shibata S, Sakamoto T, Studer R, Krainer AR, Hagiwara M. Therapeutic manipulation of IKBKAP mis-splicing with a small molecule to cure familial dysautonomia. Nat Commun 2021; 12:4507. [PMID: 34301951 PMCID: PMC8302731 DOI: 10.1038/s41467-021-24705-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 06/21/2021] [Indexed: 01/10/2023] Open
Abstract
Approximately half of genetic disease-associated mutations cause aberrant splicing. However, a widely applicable therapeutic strategy to splicing diseases is yet to be developed. Here, we analyze the mechanism whereby IKBKAP-familial dysautonomia (FD) exon 20 inclusion is specifically promoted by a small molecule splice modulator, RECTAS, even though IKBKAP-FD exon 20 has a suboptimal 5' splice site due to the IVS20 + 6 T > C mutation. Knockdown experiments reveal that exon 20 inclusion is suppressed in the absence of serine/arginine-rich splicing factor 6 (SRSF6) binding to an intronic splicing enhancer in intron 20. We show that RECTAS directly interacts with CDC-like kinases (CLKs) and enhances SRSF6 phosphorylation. Consistently, exon 20 splicing is bidirectionally manipulated by targeting cellular CLK activity with RECTAS versus CLK inhibitors. The therapeutic potential of RECTAS is validated in multiple FD disease models. Our study indicates that small synthetic molecules affecting phosphorylation state of SRSFs is available as a new therapeutic modality for mechanism-oriented precision medicine of splicing diseases.
Collapse
Affiliation(s)
- Masahiko Ajiro
- Department of Drug Discovery Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tomonari Awaya
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Young Jin Kim
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Kei Iida
- Medical Research Support Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masatsugu Denawa
- Medical Research Support Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Nobuo Tanaka
- Medical Research Support Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Ryo Kurosawa
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Shingo Matsushima
- Department of Drug Discovery Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Saiko Shibata
- Department of Drug Discovery Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tetsunori Sakamoto
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Rolenz Studer
- Center for Stem Cell Biology, Sloan Kettering Institute, New York, NY, USA
| | | | - Masatoshi Hagiwara
- Department of Drug Discovery Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan. .,Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan.
| |
Collapse
|
27
|
Artemyeva-Isman OV, Porter ACG. U5 snRNA Interactions With Exons Ensure Splicing Precision. Front Genet 2021; 12:676971. [PMID: 34276781 PMCID: PMC8283771 DOI: 10.3389/fgene.2021.676971] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/12/2021] [Indexed: 11/13/2022] Open
Abstract
Imperfect conservation of human pre-mRNA splice sites is necessary to produce alternative isoforms. This flexibility is combined with the precision of the message reading frame. Apart from intron-termini GU_AG and the branchpoint A, the most conserved are the exon-end guanine and +5G of the intron start. Association between these guanines cannot be explained solely by base-pairing with U1 snRNA in the early spliceosome complex. U6 succeeds U1 and pairs +5G in the pre-catalytic spliceosome, while U5 binds the exon end. Current U5 snRNA reconstructions by CryoEM cannot explain the conservation of the exon-end G. Conversely, human mutation analyses show that guanines of both exon termini can suppress splicing mutations. Our U5 hypothesis explains the mechanism of splicing precision and the role of these conserved guanines in the pre-catalytic spliceosome. We propose: (1) optimal binding register for human exons and U5-the exon junction positioned at U5Loop1 C39|C38; (2) common mechanism for base-pairing of human U5 snRNA with diverse exons and bacterial Ll.LtrB intron with new loci in retrotransposition-guided by base pair geometry; and (3) U5 plays a significant role in specific exon recognition in the pre-catalytic spliceosome. Statistical analyses showed increased U5 Watson-Crick pairs with the 5'exon in the absence of +5G at the intron start. In 5'exon positions -3 and -5, this effect is specific to U5 snRNA rather than U1 snRNA of the early spliceosome. Increased U5 Watson-Crick pairs with 3'exon position +1 coincide with substitutions of the conserved -3C at the intron 3'end. Based on mutation and X-ray evidence, we propose that -3C pairs with U2 G31 juxtaposing the branchpoint and the 3'intron end. The intron-termini pair, formed in the pre-catalytic spliceosome to be ready for transition after branching, and the early involvement of the 3'intron end ensure that the 3'exon contacts U5 in the pre-catalytic complex. We suggest that splicing precision is safeguarded cooperatively by U5, U6, and U2 snRNAs that stabilize the pre-catalytic complex by Watson-Crick base pairing. In addition, our new U5 model explains the splicing effect of exon-start +1G mutations: U5 Watson-Crick pairs with exon +2C/+3G strongly promote exon inclusion. We discuss potential applications for snRNA therapeutics and gene repair by reverse splicing.
Collapse
Affiliation(s)
- Olga V Artemyeva-Isman
- Gene Targeting Group, Centre for Haematology, Department of Immunology and Inflammation, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Andrew C G Porter
- Gene Targeting Group, Centre for Haematology, Department of Immunology and Inflammation, Faculty of Medicine, Imperial College London, London, United Kingdom
| |
Collapse
|
28
|
Biallelic splicing variants in the nucleolar 60S assembly factor RBM28 cause the ribosomopathy ANE syndrome. Proc Natl Acad Sci U S A 2021; 118:2017777118. [PMID: 33941690 PMCID: PMC8126767 DOI: 10.1073/pnas.2017777118] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Alopecia, neurologic defects, and endocrinopathy (ANE) syndrome is a rare ribosomopathy known to be caused by a p.(Leu351Pro) variant in the essential, conserved, nucleolar large ribosomal subunit (60S) assembly factor RBM28. We report the second family of ANE syndrome to date and a female pediatric ANE syndrome patient. The patient presented with alopecia, craniofacial malformations, hypoplastic pituitary, and hair and skin abnormalities. Unlike the previously reported patients with the p.(Leu351Pro) RBM28 variant, this ANE syndrome patient possesses biallelic precursor messenger RNA (pre-mRNA) splicing variants at the 5' splice sites of exon 5 (ΔE5) and exon 8 (ΔE8) of RBM28 (NM_018077.2:c.[541+1_541+2delinsA]; [946G > T]). In silico analyses and minigene splicing experiments in cells indicate that each splice variant specifically causes skipping of its respective mutant exon. Because the ΔE5 variant results in an in-frame 31 amino acid deletion (p.(Asp150_Lys180del)) in RBM28 while the ΔE8 variant leads to a premature stop codon in exon 9, we predicted that the ΔE5 variant would produce partially functional RBM28 but the ΔE8 variant would not produce functional protein. Using a yeast model, we demonstrate that the ΔE5 variant does indeed lead to reduced overall growth and large subunit ribosomal RNA (rRNA) production and pre-rRNA processing. In contrast, the ΔE8 variant is comparably null, implying that the partially functional ΔE5 RBM28 protein enables survival but precludes correct development. This discovery further defines the underlying molecular pathology of ANE syndrome to include genetic variants that cause aberrant splicing in RBM28 pre-mRNA and highlights the centrality of nucleolar processes in human genetic disease.
Collapse
|
29
|
Morín M, Borreguero L, Booth KT, Lachgar M, Huygen P, Villamar M, Mayo F, Barrio LC, Santos Serrão de Castro L, Morales C, Del Castillo I, Arellano B, Tellería D, Smith RJH, Azaiez H, Moreno Pelayo MA. Insights into the pathophysiology of DFNA10 hearing loss associated with novel EYA4 variants. Sci Rep 2020; 10:6213. [PMID: 32277154 PMCID: PMC7148344 DOI: 10.1038/s41598-020-63256-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 03/27/2020] [Indexed: 12/13/2022] Open
Abstract
The mutational spectrum of many genes and their contribution to the global prevalence of hereditary hearing loss is still widely unknown. In this study, we have performed the mutational screening of EYA4 gene by DHLPC and NGS in a large cohort of 531 unrelated Spanish probands and one Australian family with autosomal dominant non-syndromic hearing loss (ADNSHL). In total, 9 novel EYA4 variants have been identified, 3 in the EYA4 variable region (c.160G > T; p.Glu54*, c.781del; p.Thr261Argfs*34 and c.1078C > A; p.Pro360Thr) and 6 in the EYA-HR domain (c.1107G > T; p.Glu369Asp, c.1122G > T; p.Trp374Cys, c.1281G > A; p.Glu427Glu, c.1282-1G > A, c.1601C > G; p.S534* and an heterozygous copy number loss encompassing exons 15 to 17). The contribution of EYA4 mutations to ADNSHL in Spain is, therefore, very limited (~1.5%, 8/531). The pathophysiology of some of these novel variants has been explored. Transient expression of the c-myc-tagged EYA4 mutants in mammalian COS7 cells revealed absence of expression of the p.S534* mutant, consistent with a model of haploinsufficiency reported for all previously described EYA4 truncating mutations. However, normal expression pattern and translocation to the nucleus were observed for the p.Glu369Asp mutant in presence of SIX1. Complementary in silico analysis suggested that c.1107G > T (p.Glu369Asp), c.1281G > A (p.Glu427Glu) and c.1282-1G > A variants alter normal splicing. Minigene assays in NIH3T3 cells further confirmed that all 3 variants caused exon skipping resulting in frameshifts that lead to premature stop codons. Our study reports the first likely pathogenic synonymous variant linked to DFNA10 and provide further evidence for haploinsufficiency as the common underlying disease-causing mechanism for DFNA10-related hearing loss.
Collapse
Affiliation(s)
- Matias Morín
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Lucía Borreguero
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Kevin T Booth
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head & Surgery, University of Iowa, Iowa City, Iowa, 52242, USA.,Harvard Medical School, Department of Neurobiology, Boston, Massachusetts, 02115, USA
| | - María Lachgar
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Patrick Huygen
- Department of Otorhinolaryngology, Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands
| | - Manuela Villamar
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Fernando Mayo
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Luis Carlos Barrio
- Departamento de Investigación, Ramón y Cajal Institute of Health Research (IRYCIS), Unidad de Neurología Experimental, 28034, Madrid, Spain
| | - Luciana Santos Serrão de Castro
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Carmelo Morales
- Servicio de Otorrinolaringología, Hospital Universitario Marqués de Valdecilla, 39008, Santander, Spain
| | - Ignacio Del Castillo
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Beatriz Arellano
- Servicio de Otorrinolaringología, Hospital Universitario Puerta de Hierro, Majadahonda, 28922, Madrid, Spain
| | - Dolores Tellería
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain
| | - Richard J H Smith
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head & Surgery, University of Iowa, Iowa City, Iowa, 52242, USA
| | - Hela Azaiez
- Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology, Head & Surgery, University of Iowa, Iowa City, Iowa, 52242, USA
| | - M A Moreno Pelayo
- Servicio de Genética, Ramón y Cajal Institute of Health Research (IRYCIS) and Biomedical Network Research Centre on Rare Diseases (CIBERER), 28034, Madrid, Spain.
| |
Collapse
|
30
|
A Silent Exonic Mutation in a Rice Integrin-α FG-GAP Repeat-Containing Gene Causes Male-Sterility by Affecting mRNA Splicing. Int J Mol Sci 2020; 21:ijms21062018. [PMID: 32188023 PMCID: PMC7139555 DOI: 10.3390/ijms21062018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/12/2020] [Accepted: 03/14/2020] [Indexed: 12/11/2022] Open
Abstract
Pollen development plays crucial roles in the life cycle of higher plants. Here we characterized a rice mutant with complete male-sterile phenotype, pollen-less 1 (pl1). pl1 exhibited smaller anthers with arrested pollen development, absent Ubisch bodies, necrosis-like tapetal hypertrophy, and smooth anther cuticular surface. Molecular mapping revealed a synonymous mutation in the fourth exon of PL1 co-segregated with the mutant phenotype. This mutation disrupts the exon-intron splice junction in PL1, generating aberrant mRNA species and truncated proteins. PL1 is highly expressed in the tapetal cells of developing anther, and its protein is co-localized with plasma membrane (PM) and endoplasmic reticulum (ER) signal. PL1 encodes an integrin-α FG-GAP repeat-containing protein, which has seven β-sheets and putative Ca2+-binding motifs and is broadly conserved in terrestrial plants. Our findings therefore provide insights into both the role of integrin-α FG-GAP repeat-containing protein in rice male fertility and the influence of exonic mutation on intronic splice donor site selection.
Collapse
|
31
|
Glaich O, Leader Y, Lev Maor G, Ast G. Histone H1.5 binds over splice sites in chromatin and regulates alternative splicing. Nucleic Acids Res 2019; 47:6145-6159. [PMID: 31076740 PMCID: PMC6614845 DOI: 10.1093/nar/gkz338] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 04/17/2019] [Accepted: 04/27/2019] [Indexed: 12/11/2022] Open
Abstract
Chromatin organization and epigenetic markers influence splicing, though the magnitudes of these effects and the mechanisms are largely unknown. Here, we demonstrate that linker histone H1.5 influences mRNA splicing. We observed that linker histone H1.5 binds DNA over splice sites of short exons in human lung fibroblasts (IMR90 cells). We found that association of H1.5 with these splice sites correlated with the level of inclusion of alternatively spliced exons. Exons marked by H1.5 had more RNA polymerase II (RNAP II) stalling near the 3' splice site than did exons not associated with H1.5. In cells depleted of H1.5, we showed that the inclusion of five exons evaluated decreased and that RNAP II levels over these exons were also reduced. Our findings indicate that H1.5 is involved in regulation of splice site selection and alternative splicing, a function not previously demonstrated for linker histones.
Collapse
Affiliation(s)
- Ohad Glaich
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Yodfat Leader
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Galit Lev Maor
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Gil Ast
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv 69978, Israel
| |
Collapse
|
32
|
Shi J, Deng Y, Huang S, Huang C, Wang J, Xiang AP, Yao C. Suboptimal RNA-RNA interaction limits U1 snRNP inhibition of canonical mRNA 3' processing. RNA Biol 2019; 16:1448-1460. [PMID: 31242075 DOI: 10.1080/15476286.2019.1636596] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
It is increasingly appreciated that U1 snRNP transcriptomically suppresses the usage of intronic polyadenylation site (PAS) of mRNAs, an outstanding question is why frequently used PASs are not suppressed. Here we found that U1 snRNP could be transiently associated with sequences upstream of actionable PASs in human cells, and RNA-RNA interaction might contribute to the association. By focusing on individual PAS, we showed that the stable assembly of U1 snRNP near PAS might be generally required for U1 inhibition of mRNA 3' processing. Therefore, actionable PASs that often lack optimal U1 snRNP docking site nearby is free from U1 inhibitory effect. Consistently, natural 5' splicing site (5'-SS) is moderately enriched ~250 nt upstream of intronic PASs whose usage is sensitive to functional knockdown of U1 snRNA. Collectively, our results provided an insight into how U1 snRNP selectively inhibits the usage of PASs in a cellular context, and supported a prevailing model that U1 snRNP scans pre-mRNA through RNA-RNA interaction to find a stable interaction site to exercise its function in pre-mRNA processing, including repressing the usage of cryptic PASs.
Collapse
Affiliation(s)
- Junjie Shi
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University , Guangzhou , China
| | - Yanhui Deng
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University , Guangzhou , China
| | - Shanshan Huang
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University , Guangzhou , China
| | - Chunliu Huang
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University , Guangzhou , China
| | - Jinkai Wang
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University , Guangzhou , China.,RNA Biomedical Institute, Sun Yat-sen Memorial Hospital, Sun Yat-sen University , Guangzhou , China.,Center for Precision Medicine, Sun Yat-sen University , Guangzhou , China
| | - Andy Peng Xiang
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University , Guangzhou , China
| | - Chengguo Yao
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University , Guangzhou , China.,Department of Genetics and Cell Biology, Zhongshan School of Medicine, Sun Yat-sen University , Guangzhou , China
| |
Collapse
|
33
|
Lee B, Kim YR, Kim SJ, Goh SH, Kim JH, Oh SK, Baek JI, Kim UK, Lee KY. Modified U1 snRNA and antisense oligonucleotides rescue splice mutations in SLC26A4 that cause hereditary hearing loss. Hum Mutat 2019; 40:1172-1180. [PMID: 31033086 DOI: 10.1002/humu.23774] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 04/15/2019] [Accepted: 04/23/2019] [Indexed: 11/11/2022]
Abstract
One of most important factors for messenger RNA (mRNA) transcription is the spliceosomal component U1 small nuclear RNA (snRNA), which recognizes 5' splicing donor sites at specific regions in pre-mRNA. Mutations in these sites disrupt U1 snRNA binding and cause abnormal splicing. In this study, we investigated mutations at splice sites in SLC26A4 (HGNC 8818), one of the major causative genes of hearing loss, which may result in the synthesis of abnormal pendrin, the channel protein encoded by the gene. Seventeen SLC26A4 variants with mutations in the U1 snRNA binding sites were assessed by minigene splicing assays, and 11 were found to result in abnormal splicing. Interestingly, eight of the 11 pathogenic mutations were intronic, suggesting the importance of conserved sequences at the intronic splice site. The application of modified U1 snRNA effectively rescued the abnormal splicing for most of these mutations. Although three were cryptic mutations, they were rescued by cotransfection of modified U1 snRNA and modified antisense oligonucleotides. Our results demonstrate the important role of snRNA in SLC26A4 mutations, suggesting the therapeutic potential of modified U1 snRNA and antisense oligonucleotides for neutralizing the pathogenic effect of the splice-site mutations that may result in hearing loss.
Collapse
Affiliation(s)
- Byeonghyeon Lee
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea.,BK21 Plus KNU Creative BioResearch Group, School of Life Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Ye-Ri Kim
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea.,BK21 Plus KNU Creative BioResearch Group, School of Life Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Sang-Joo Kim
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea.,BK21 Plus KNU Creative BioResearch Group, School of Life Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Sung-Ho Goh
- Therapeutic Target Discovery Branch, National Cancer Center, Goyang-si, Gyeonggi-do, Republic of Korea
| | - Jong-Heun Kim
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea.,BK21 Plus KNU Creative BioResearch Group, School of Life Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Se-Kyung Oh
- Laboratory Animal Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu, Republic of Korea
| | - Jeong-In Baek
- Department of Aroma-Applied Industry, Daegu Haany University, Gyeongsan, Republic of Korea
| | - Un-Kyung Kim
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea.,BK21 Plus KNU Creative BioResearch Group, School of Life Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Kyu-Yup Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| |
Collapse
|
34
|
Miller JE, Veturi Y, Ritchie MD. Innovative strategies for annotating the "relationSNP" between variants and molecular phenotypes. BioData Min 2019; 12:10. [PMID: 31114635 PMCID: PMC6518798 DOI: 10.1186/s13040-019-0197-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 04/18/2019] [Indexed: 11/10/2022] Open
Abstract
Characterizing how variation at the level of individual nucleotides contributes to traits and diseases has been an area of growing interest since the completion of sequencing the first human genome. Our understanding of how a single nucleotide polymorphism (SNP) leads to a pathogenic phenotype on a genome-wide scale is a fruitful endeavor for anyone interested in developing diagnostic tests, therapeutics, or simply wanting to understand the etiology of a disease or trait. To this end, many datasets and algorithms have been developed as resources/tools to annotate SNPs. One of the most common practices is to annotate coding SNPs that affect the protein sequence. Synonymous variants are often grouped as one type of variant, however there are in fact many tools available to dissect their effects on gene expression. More recently, large consortiums like ENCODE and GTEx have made it possible to annotate non-coding regions. Although annotating variants is a common technique among human geneticists, the constant advances in tools and biology surrounding SNPs requires an updated summary of what is known and the trajectory of the field. This review will discuss the history behind SNP annotation, commonly used tools, and newer strategies for SNP annotation. Additionally, we will comment on the caveats that distinguish approaches from one another, along with gaps in the current state of knowledge, and potential future directions. We do not intend for this to be a comprehensive review for any specific area of SNP annotation, but rather it will be an excellent resource for those unfamiliar with computational tools used to functionally characterize SNPs. In summary, this review will help illustrate how each SNP annotation method impacts the way in which the genetic and molecular etiology of a disease is explored in-silico.
Collapse
Affiliation(s)
- Jason E. Miller
- Department of Genetics, Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd., Philadelphia, PA 19104 USA
| | - Yogasudha Veturi
- Department of Genetics, Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd., Philadelphia, PA 19104 USA
| | - Marylyn D. Ritchie
- Department of Genetics, Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd., Philadelphia, PA 19104 USA
| |
Collapse
|
35
|
Yannai S, Zonszain J, Donyo M, Ast G. Combinatorial treatment increases IKAP levels in human cells generated from Familial Dysautonomia patients. PLoS One 2019; 14:e0211602. [PMID: 30889183 PMCID: PMC6424424 DOI: 10.1371/journal.pone.0211602] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 03/07/2019] [Indexed: 02/06/2023] Open
Abstract
Familial Dysautonomia (FD) is an autosomal recessive congenital neuropathy that results from a point mutation at the 5' splice site of intron 20 in the IKBKAP gene. This mutation decreases production of the IKAP protein, and treatments that increase the level of the full-length IKBKAP transcript are likely to be of therapeutic value. We previously found that phosphatidylserine (PS), an FDA-approved food supplement, elevates IKAP levels in cells generated from FD patients. Here we demonstrate that combined treatment of cells generated from FD patients with PS and kinetin or PS and the histone deacetylase inhibitor trichostatin A (TSA) resulted in an additive elevation of IKAP compared to each drug alone. This indicates that the compounds influence different pathways. We also found that pridopidine enhances production of IKAP in cells generated from FD patients. Pridopidine has an additive effect on IKAP levels when used in combination with kinetin or TSA, but not with PS; suggesting that PS and pridopidine influence IKBKAP levels through the same mechanism. Indeed, we demonstrate that the effect of PS and pridopidine is through sigma-1 receptor-mediated activation of the BDNF signaling pathway. A combination treatment with any of these drugs with different mechanisms has potential to benefit FD patients.
Collapse
Affiliation(s)
- Sivan Yannai
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Jonathan Zonszain
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Maya Donyo
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Gil Ast
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
- * E-mail:
| |
Collapse
|
36
|
Amiñoso C, Gordillo-Marañón M, Hernández J, Solera J. Reevaluating the pathogenicity of the mutation c.1194 +5 G>A in GAA gene by functional analysis of RNA in a 61-year-old woman diagnosed with Pompe disease by muscle biopsy. Neuromuscul Disord 2019; 29:187-191. [PMID: 30770309 DOI: 10.1016/j.nmd.2018.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 12/05/2018] [Accepted: 12/09/2018] [Indexed: 11/18/2022]
Abstract
Glycogen storage disease type II, or Pompe disease, is an autosomal recessive disorder caused by deficiency of lysosomal acid alpha-glucosidase (GAA). We performed genetic analysis to confirm the diagnosis of Pompe disease in a 61-year-old patient with progressive weakness in extremities, severe Sleep Apnea-Hypopnea Syndrome, a significant reduction of alpha-glucosidase in liquid sample of peripheral blood and muscular biopsy diagnosis. GAA gene sequencing showed the patient is homozygous for the splice-site mutation c.1194+5G>A, considered as nonpathogenic in Pompe Center mutation database. Further molecular RNA characterization of GAA transcripts allowed us to identify abnormal processing of pre-mRNA, leading to aberrant transcripts and a significant reduction of GAA mRNA levels. Our results indicate that c.1194+5G>A is a pathogenic splice-site mutation and should be considered as such for diagnostic purposes. This study emphasizes the potential role of functional studies to determine the consequences of mutations with no evident pathogenicity.
Collapse
Affiliation(s)
- Cinthia Amiñoso
- Unidad de Oncogenética Molecular, Instituto de Genética Médica y Molecular (INGEMM), Edificio Quirúrgico Planta-2, Hospital Universitario La Paz, 28046 Madrid, Spain
| | - María Gordillo-Marañón
- Unidad de Oncogenética Molecular, Instituto de Genética Médica y Molecular (INGEMM), Edificio Quirúrgico Planta-2, Hospital Universitario La Paz, 28046 Madrid, Spain; Institute of Cardiovascular Science, Faculty of Population Health, University College London, London WC1E 6BT, UK
| | - Jaime Hernández
- Neurology Department, University General Hospital of Guadalajara, Spain
| | - Jesús Solera
- Unidad de Oncogenética Molecular, Instituto de Genética Médica y Molecular (INGEMM), Edificio Quirúrgico Planta-2, Hospital Universitario La Paz, 28046 Madrid, Spain; Department of Biochemistry, Faculty of Medicine, Autonoma University of Madrid, 28046 Madrid, Spain.
| |
Collapse
|
37
|
Jourdy Y, Fretigny M, Nougier C, Négrier C, Bozon D, Vinciguerra C. Splicing analysis of 26 F8 nucleotide variations using a minigene assay. Haemophilia 2019; 25:306-315. [PMID: 30690819 DOI: 10.1111/hae.13687] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 12/05/2018] [Accepted: 01/08/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND Classically, the study of splicing impact of variation located near the splice site is performed by both in silico and mRNA analysis. However, RNA sample was rarely available. OBJECTIVE To characterize a panel of putative haemophilia A splicing variations. MATERIALS AND METHODS Twenty-six F8 variations identified from a cohort of 2075 haemophilia A families were studied using both bioinformatic tools and in vitro minigene assays in HeLa and Huh7 cells. RESULTS An aberrant splicing was demonstrated for 21/26 tested sequence variations. A good correlation between in silico and in vitro analysis was obtained for variations affecting donor splice site (12/14) and for the synonymous variations located inside an exon (6/6). Conversely, no concordant results were observed for the six variations affecting acceptor splice sites. The variations resulted more frequently in exon skipping (n = 13) than in activation of nearby cryptic splice sites (n = 5), in use of a de novo splice site (n = 2) or in insertion of large intronic sequences (n = 1). This study allowed to reclassify 5 synonymous substitutions c.1167A>G (p.Gln389Gln), c.1569G>T (p.Leu523Leu), c.1752G>A (p.Gln584Gln), c.5586G>A (p.Leu1862Leu) and c.6066C>T (p.Gly2022Gly) as splicing variations. The pathological significance of five variations remained unclear (c.222G>A [p.Thr74Thr], c.237C>T [p.Asn79Asn], c.240C>T [p.Ile80Ile], c.2113+5_2113+8del and c.2113+5G>A). DISCUSSION The minigene assay herein gave additional evidences for the clinical significance of 21/26 F8 putative splice site mutations. Such investigation should be performed for each F8 putative splice site variation for which no mRNA sample is available, notably to greatly improve the genetic counselling given to female carriers.
Collapse
Affiliation(s)
- Yohann Jourdy
- Service d'Hématologie Biologique, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Lyon, France.,EA 4609 Hémostase et Cancer, Université Claude Bernard Lyon 1, University Lyon, Lyon, France
| | - Mathilde Fretigny
- Service d'Hématologie Biologique, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Lyon, France
| | - Christophe Nougier
- Service d'Hématologie Biologique, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Lyon, France
| | - Claude Négrier
- Service d'Hématologie Biologique, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Lyon, France.,EA 4609 Hémostase et Cancer, Université Claude Bernard Lyon 1, University Lyon, Lyon, France
| | - Dominique Bozon
- Laboratoire de Cardiogénétique Moléculaire, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Lyon, France
| | - Christine Vinciguerra
- Service d'Hématologie Biologique, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Lyon, France.,EA 4609 Hémostase et Cancer, Université Claude Bernard Lyon 1, University Lyon, Lyon, France
| |
Collapse
|
38
|
Han F, Yuan K, Kong C, Zhang X, Yang L, Zhuang M, Zhang Y, Li Z, Wang Y, Fang Z, Lv H. Fine mapping and candidate gene identification of the genic male-sterile gene ms3 in cabbage 51S. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2018; 131:2651-2661. [PMID: 30238254 DOI: 10.1007/s00122-018-3180-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 09/03/2018] [Indexed: 05/27/2023]
Abstract
The ms3 gene responsible for a male-sterile phenotype in cabbage was mapped to a 187.4-kb genomic fragment. The gene BoTPD1, a homolog of Arabidopsis TPD1, was identified as a strong candidate gene. Cabbage 51S is a spontaneous male-sterile mutant. Phenotypic investigation revealed defects in anther cell differentiation, with failure to form the tapetum layer and complete abortion of microsporocytes before the tetrad stage. Genetic analysis indicated that this male sterility was controlled by a single recessive gene, ms3. Using an F2 population, we mapped ms3 to a 187.4-kb interval. BoTPD1 was identified as a candidate from this interval. Sequence analysis revealed an intronic 182-bp insertion in 51S that interrupted the conserved motif at the 5' splicing site of the third intron, possibly resulting in a truncated transcript. Analyses of BoTPD1 homologous proteins revealed evolutionarily conserved roles in anther cell fate determination during reproductive development. RT-PCR showed that BoTPD1 was expressed in various tissues, excluding the root, and high expression levels were detected in anthers and buds. A BoTPD1-specific marker based on the 182-bp insertion cosegregated with male sterility and can be used for marker-assisted selection.
Collapse
Affiliation(s)
- Fengqing Han
- Germplasm Innovation in Northwest China, Ministry of Agriculture; College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China
| | - Kaiwen Yuan
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China
| | - Congcong Kong
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China
| | - Xiaoli Zhang
- Tianjin Kernel Vegetable Research Institute, Jinjing Road, Xiqing District, Tianjin, 300384, China
| | - Limei Yang
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China
| | - Mu Zhuang
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China
| | - Yangyong Zhang
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China
| | - Zhansheng Li
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China
| | - Yong Wang
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China
| | - Zhiyuan Fang
- Germplasm Innovation in Northwest China, Ministry of Agriculture; College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China.
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China.
| | - Honghao Lv
- Institute of Vegetables and Flowers, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Chinese Academy of Agricultural Sciences, #12 Zhong Guan Cun Nandajie Street, Beijing, 100081, China.
| |
Collapse
|
39
|
Wong MS, Kinney JB, Krainer AR. Quantitative Activity Profile and Context Dependence of All Human 5' Splice Sites. Mol Cell 2018; 71:1012-1026.e3. [PMID: 30174293 DOI: 10.1016/j.molcel.2018.07.033] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 06/18/2018] [Accepted: 07/23/2018] [Indexed: 02/02/2023]
Abstract
Pre-mRNA splicing is an essential step in the expression of most human genes. Mutations at the 5' splice site (5'ss) frequently cause defective splicing and disease due to interference with the initial recognition of the exon-intron boundary by U1 small nuclear ribonucleoprotein (snRNP), a component of the spliceosome. Here, we use a massively parallel splicing assay (MPSA) in human cells to quantify the activity of all 32,768 unique 5'ss sequences (NNN/GYNNNN) in three different gene contexts. Our results reveal that although splicing efficiency is mostly governed by the 5'ss sequence, there are substantial differences in this efficiency across gene contexts. Among other uses, these MPSA measurements facilitate the prediction of 5'ss sequence variants that are likely to cause aberrant splicing. This approach provides a framework to assess potential pathogenic variants in the human genome and streamline the development of splicing-corrective therapies.
Collapse
Affiliation(s)
- Mandy S Wong
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Justin B Kinney
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
| | - Adrian R Krainer
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
| |
Collapse
|
40
|
Shiraishi Y, Kataoka K, Chiba K, Okada A, Kogure Y, Tanaka H, Ogawa S, Miyano S. A comprehensive characterization of cis-acting splicing-associated variants in human cancer. Genome Res 2018; 28:1111-1125. [PMID: 30012835 PMCID: PMC6071634 DOI: 10.1101/gr.231951.117] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 06/29/2018] [Indexed: 12/21/2022]
Abstract
Although many driver mutations are thought to promote carcinogenesis via abnormal splicing, the landscape of splicing-associated variants (SAVs) remains unknown due to the complexity of splicing abnormalities. Here, we developed a statistical framework to systematically identify SAVs disrupting or newly creating splice site motifs and applied it to matched whole-exome and transcriptome sequencing data from 8976 samples across 31 cancer types, generating a catalog of 14,438 SAVs. Such a large collection of SAVs enabled us to characterize their genomic features, underlying mutational processes, and influence on cancer driver genes. In fact, ∼50% of SAVs identified were those disrupting noncanonical splice sites (non-GT-AG dinucleotides), including the third and fifth intronic bases of donor sites, or newly creating splice sites. Mutation signature analysis revealed that tobacco smoking is more strongly associated with SAVs, whereas ultraviolet exposure has less impact. SAVs showed remarkable enrichment of cancer-related genes, and as many as 14.7% of samples harbored at least one SAVs affecting them, particularly in tumor suppressors. In addition to intron retention, whose association with tumor suppressor inactivation has been previously reported, exon skipping and alternative splice site usage caused by SAVs frequently affected tumor suppressors. Finally, we described high-resolution distributions of SAVs along the gene and their splicing outcomes in commonly disrupted genes, including TP53, PIK3R1, GATA3, and CDKN2A, which offers genetic clues for understanding their functional properties. Collectively, our findings delineate a comprehensive portrait of SAVs, novel insights into transcriptional de-regulation in cancer.
Collapse
Affiliation(s)
- Yuichi Shiraishi
- Laboratory of DNA Information Analysis, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| | - Keisuke Kataoka
- Department of Pathology and Tumor Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan.,Division of Molecular Oncology, National Cancer Center Research Institute, Tokyo 104-0045, Japan
| | - Kenichi Chiba
- Laboratory of DNA Information Analysis, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| | - Ai Okada
- Laboratory of DNA Information Analysis, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| | - Yasunori Kogure
- Department of Pathology and Tumor Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Hiroko Tanaka
- Laboratory of DNA Information Analysis, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| | - Seishi Ogawa
- Department of Pathology and Tumor Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Satoru Miyano
- Laboratory of DNA Information Analysis, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| |
Collapse
|
41
|
Donadon I, Pinotti M, Rajkowska K, Pianigiani G, Barbon E, Morini E, Motaln H, Rogelj B, Mingozzi F, Slaugenhaupt SA, Pagani F. Exon-specific U1 snRNAs improve ELP1 exon 20 definition and rescue ELP1 protein expression in a familial dysautonomia mouse model. Hum Mol Genet 2018; 27:2466-2476. [PMID: 29701768 PMCID: PMC6030917 DOI: 10.1093/hmg/ddy151] [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: 01/16/2018] [Revised: 04/12/2018] [Accepted: 04/16/2018] [Indexed: 12/30/2022] Open
Abstract
Familial dysautonomia (FD) is a rare genetic disease with no treatment, caused by an intronic point mutation (c.2204+6T>C) that negatively affects the definition of exon 20 in the elongator complex protein 1 gene (ELP1 also known as IKBKAP). This substitution modifies the 5' splice site and, in combination with regulatory splicing factors, induces different levels of exon 20 skipping, in various tissues. Here, we evaluated the therapeutic potential of a novel class of U1 snRNA molecules, exon-specific U1s (ExSpeU1s), in correcting ELP1 exon 20 recognition. Lentivirus-mediated expression of ELP1-ExSpeU1 in FD fibroblasts improved ELP1 splicing and protein levels. We next focused on a transgenic mouse model that recapitulates the same tissue-specific mis-splicing seen in FD patients. Intraperitoneal delivery of ELP1-ExSpeU1s-adeno-associated virus particles successfully increased the production of full-length human ELP1 transcript and protein. This splice-switching class of molecules is the first to specifically correct the ELP1 exon 20 splicing defect. Our data provide proof of principle of ExSpeU1s-adeno-associated virus particles as a novel therapeutic strategy for FD.
Collapse
Affiliation(s)
- Irving Donadon
- Human Molecular Genetics Laboratory, International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Mirko Pinotti
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Katarzyna Rajkowska
- Human Molecular Genetics Laboratory, International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Giulia Pianigiani
- Human Molecular Genetics Laboratory, International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | | | - Elisabetta Morini
- Center for Genomic Medicine, Massachusetts General Hospital Research Institute and Harvard Medical School, Boston, MA, USA
| | - Helena Motaln
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Boris Rogelj
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
- Biomedical Research Institute BRIS, Ljubljana, Slovenia
| | - Federico Mingozzi
- Genethon and INSERM U951, Evry, France
- University Pierre and Marie Curie and INSERM U974, Paris, France
| | - Susan A Slaugenhaupt
- Center for Genomic Medicine, Massachusetts General Hospital Research Institute and Harvard Medical School, Boston, MA, USA
| | - Franco Pagani
- Human Molecular Genetics Laboratory, International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| |
Collapse
|
42
|
Elayaperumal S, Fouzia NA, Biswas A, Nair SC, Viswabandya A, George B, Abraham A, Oldenburg J, Edison ES, Srivastava A. Type-3 von Willebrand disease in India-Clinical spectrum and molecular profile. Haemophilia 2018; 24:930-940. [PMID: 29984440 DOI: 10.1111/hae.13542] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/08/2018] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Type 3 von Willebrand disease (VWD) is the rare and most severe form of VWD which results from a near-complete deficiency of the von Willebrand factor (VWF). This study evaluates in detail the molecular pathology of type-3 VWD in India. One hundred and two patients from 90 families were evaluated. PATIENTS AND METHODS Phenotypic data, including bleeding scores (BS), were documented using structured questionnaires. Diagnosis of type 3 VWD was based on undetectable VWF antigen levels in the plasma. Genomic DNA from these patients was screened for mutations in VWF gene. Structural modeling and expression studies were carried out for missense mutations. RESULTS Out of 102 patients, mutations could be identified in 91% (n = 93). Fifty-five different gene variants were identified. Thirty-four (61.8%) were novel. Mutations could be identified in both the alleles in 90 patients, while no causative mutation could be identified in 9 patients; twenty-four (23.5%) patients had mutations clustered in the propeptide region of VWF. Interestingly, five mutations accounted for the defects in 37/93 (39.8%) patients. Structural analysis and in vitro studies on missense mutations imply impaired processes associated with secretion of VWF. CONCLUSION This study is one of the largest series to define the molecular basis of type-3 VWD.
Collapse
Affiliation(s)
- S Elayaperumal
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - N A Fouzia
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - A Biswas
- Institute of Experimental Hematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - S C Nair
- Department of Immunohaematology & Transfusion Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - A Viswabandya
- Princess Margaret Cancer Center, Toronto, Ontario, Canada
| | - B George
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - A Abraham
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - J Oldenburg
- Institute of Experimental Hematology and Transfusion Medicine, University Clinic Bonn, Bonn, Germany
| | - E S Edison
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - A Srivastava
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| |
Collapse
|
43
|
Martínez-Pizarro A, Dembic M, Pérez B, Andresen BS, Desviat LR. Intronic PAH gene mutations cause a splicing defect by a novel mechanism involving U1snRNP binding downstream of the 5' splice site. PLoS Genet 2018; 14:e1007360. [PMID: 29684050 PMCID: PMC5933811 DOI: 10.1371/journal.pgen.1007360] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 05/03/2018] [Accepted: 04/11/2018] [Indexed: 11/18/2022] Open
Abstract
Phenylketonuria (PKU), one of the most common inherited diseases of amino acid metabolism, is caused by mutations in the phenylalanine hydroxylase (PAH) gene. Recently, PAH exon 11 was identified as a vulnerable exon due to a weak 3’ splice site, with different exonic mutations affecting exon 11 splicing through disruption of exonic splicing regulatory elements. In this study, we report a novel intron 11 regulatory element, which is involved in exon 11 splicing, as revealed by the investigated pathogenic effect of variants c.1199+17G>A and c.1199+20G>C, identified in PKU patients. Both mutations cause exon 11 skipping in a minigene system. RNA binding assays indicate that binding of U1snRNP70 to this intronic region is disrupted, concomitant with a slightly increased binding of inhibitors hnRNPA1/2. We have investigated the effect of deletions and point mutations, as well as overexpression of adapted U1snRNA to show that this splicing regulatory motif is important for regulation of correct splicing at the natural 5’ splice site. The results indicate that U1snRNP binding downstream of the natural 5’ splice site determines efficient exon 11 splicing, thus providing a basis for development of therapeutic strategies to correct PAH exon 11 splicing mutations. In this work, we expand the functional effects of non-canonical intronic U1 snRNP binding by showing that it may enhance exon definition and that, consequently, intronic mutations may cause exon skipping by a novel mechanism, where they disrupt stimulatory U1 snRNP binding close to the 5’ splice site. Notably, our results provide further understanding of the reported therapeutic effect of exon specific U1 snRNA for splicing mutations in disease. Splicing defects constitute a major cause of human disease. Mutations affecting conserved splicing sequences at exon-intron junctions are easily recognized as possibly pathogenic, whereas variants in exonic or intronic regions are difficult to classify without functional evidence provided by transcript analysis or in vitro analysis using minigenes. In this work, we sought out to study the pathogenicity of two novel intronic PAH variants identified in phenylketonuria patients. Both mutations resulted in exon skipping in minigenes. We demonstrate that U1snRNP70 binds to the intronic region and that this binding is abolished in the mutant sequences. Correction of the splicing defect was achieved using modified U1 snRNA perfectly complementary to each of the mutant sequences. The results extend the repertoire of natural U1 snRNP cellular functions by including its role as splicing enhancer via binding downstream of the natural 5’ splice site. In addition, our results correlate with the described therapeutic effect of modified U1snRNP for splicing mutations in different genes, thus having a significant impact in the development of specific therapies for splicing defects.
Collapse
Affiliation(s)
- Ainhoa Martínez-Pizarro
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, CEDEM, CIBERER, IdiPaz, Universidad Autónoma, Madrid, Spain
| | - Maja Dembic
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense, Denmark
| | - Belén Pérez
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, CEDEM, CIBERER, IdiPaz, Universidad Autónoma, Madrid, Spain
| | - Brage S. Andresen
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense, Denmark
- * E-mail: (BSA); (LRD)
| | - Lourdes R. Desviat
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, CEDEM, CIBERER, IdiPaz, Universidad Autónoma, Madrid, Spain
- * E-mail: (BSA); (LRD)
| |
Collapse
|
44
|
Anna A, Monika G. Splicing mutations in human genetic disorders: examples, detection, and confirmation. J Appl Genet 2018; 59:253-268. [PMID: 29680930 PMCID: PMC6060985 DOI: 10.1007/s13353-018-0444-7] [Citation(s) in RCA: 426] [Impact Index Per Article: 60.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Revised: 04/08/2018] [Accepted: 04/10/2018] [Indexed: 01/02/2023]
Abstract
Precise pre-mRNA splicing, essential for appropriate protein translation, depends on the presence of consensus "cis" sequences that define exon-intron boundaries and regulatory sequences recognized by splicing machinery. Point mutations at these consensus sequences can cause improper exon and intron recognition and may result in the formation of an aberrant transcript of the mutated gene. The splicing mutation may occur in both introns and exons and disrupt existing splice sites or splicing regulatory sequences (intronic and exonic splicing silencers and enhancers), create new ones, or activate the cryptic ones. Usually such mutations result in errors during the splicing process and may lead to improper intron removal and thus cause alterations of the open reading frame. Recent research has underlined the abundance and importance of splicing mutations in the etiology of inherited diseases. The application of modern techniques allowed to identify synonymous and nonsynonymous variants as well as deep intronic mutations that affected pre-mRNA splicing. The bioinformatic algorithms can be applied as a tool to assess the possible effect of the identified changes. However, it should be underlined that the results of such tests are only predictive, and the exact effect of the specific mutation should be verified in functional studies. This article summarizes the current knowledge about the "splicing mutations" and methods that help to identify such changes in clinical diagnosis.
Collapse
Affiliation(s)
- Abramowicz Anna
- Department of Medical Genetics, Institute of Mother and Child, Kasprzaka 17a, 01-211, Warsaw, Poland
| | - Gos Monika
- Department of Medical Genetics, Institute of Mother and Child, Kasprzaka 17a, 01-211, Warsaw, Poland.
| |
Collapse
|
45
|
Giau VV, Bagyinszky E, An SSA, Kim S. Clinical genetic strategies for early onset neurodegenerative diseases. Mol Cell Toxicol 2018. [DOI: 10.1007/s13273-018-0015-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
46
|
Singh NN, Del Rio-Malewski JB, Luo D, Ottesen EW, Howell MD, Singh RN. Activation of a cryptic 5' splice site reverses the impact of pathogenic splice site mutations in the spinal muscular atrophy gene. Nucleic Acids Res 2017; 45:12214-12240. [PMID: 28981879 PMCID: PMC5716214 DOI: 10.1093/nar/gkx824] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 09/06/2017] [Indexed: 01/08/2023] Open
Abstract
Spinal muscular atrophy (SMA) is caused by deletions or mutations of the Survival Motor Neuron 1 (SMN1) gene coupled with predominant skipping of SMN2 exon 7. The only approved SMA treatment is an antisense oligonucleotide that targets the intronic splicing silencer N1 (ISS-N1), located downstream of the 5' splice site (5'ss) of exon 7. Here, we describe a novel approach to exon 7 splicing modulation through activation of a cryptic 5'ss (Cr1). We discovered the activation of Cr1 in transcripts derived from SMN1 that carries a pathogenic G-to-C mutation at the first position (G1C) of intron 7. We show that Cr1-activating engineered U1 snRNAs (eU1s) have the unique ability to reprogram pre-mRNA splicing and restore exon 7 inclusion in SMN1 carrying a broad spectrum of pathogenic mutations at both the 3'ss and 5'ss of the exon 7. Employing a splicing-coupled translation reporter, we demonstrate that mRNAs generated by an eU1-induced activation of Cr1 produce full-length SMN. Our findings underscore a wider role for U1 snRNP in splicing regulation and reveal a novel approach for the restoration of SMN exon 7 inclusion for a potential therapy of SMA.
Collapse
Affiliation(s)
- Natalia N Singh
- Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - José Bruno Del Rio-Malewski
- Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA.,Interdepartmental Genetics and Genomics Program, Iowa State University, Ames, IA 50011, USA
| | - Diou Luo
- Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Eric W Ottesen
- Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Matthew D Howell
- Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Ravindra N Singh
- Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA.,Interdepartmental Genetics and Genomics Program, Iowa State University, Ames, IA 50011, USA
| |
Collapse
|
47
|
Rubin BY, Anderson SL. IKBKAP/ELP1 gene mutations: mechanisms of familial dysautonomia and gene-targeting therapies. APPLICATION OF CLINICAL GENETICS 2017; 10:95-103. [PMID: 29290691 PMCID: PMC5735983 DOI: 10.2147/tacg.s129638] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The successful completion of the Human Genome Project led to the discovery of the molecular basis of thousands of genetic disorders. The identification of the mutations that cause familial dysautonomia (FD), an autosomal recessive disorder that impacts sensory and autonomic neurons, was aided by the release of the human DNA sequence. The identification and characterization of the genetic cause of FD have changed the natural history of this disease. Genetic testing programs, which were established shortly after the disease-causing mutations were identified, have almost completely eliminated the birth of children with this disorder. Characterization of the principal disease-causing mutation has led to the development of therapeutic modalities that ameliorate its effect, while the development of mouse models that recapitulate the impact of the mutation has allowed for the in-depth characterization of its impact on neuronal development and survival. The intense research focus on this disorder, while clearly benefiting the FD patient population, also serves as a model for the positive impact focused research efforts can have on the future of other genetic diseases. Here, we present the research advances and scientific breakthroughs that have changed and will continue to change the natural history of this centuries-old genetic disease.
Collapse
Affiliation(s)
- Berish Y Rubin
- Department of Biological Sciences, Fordham University, Bronx, NY, USA
| | - Sylvia L Anderson
- Department of Biological Sciences, Fordham University, Bronx, NY, USA
| |
Collapse
|
48
|
Nanan KK, Ocheltree C, Sturgill D, Mandler MD, Prigge M, Varma G, Oberdoerffer S. Independence between pre-mRNA splicing and DNA methylation in an isogenic minigene resource. Nucleic Acids Res 2017; 45:12780-12797. [PMID: 29244186 PMCID: PMC5727405 DOI: 10.1093/nar/gkx900] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 09/13/2017] [Accepted: 09/25/2017] [Indexed: 12/27/2022] Open
Abstract
Actively transcribed genes adopt a unique chromatin environment with characteristic patterns of enrichment. Within gene bodies, H3K36me3 and cytosine DNA methylation are elevated at exons of spliced genes and have been implicated in the regulation of pre-mRNA splicing. H3K36me3 is further responsive to splicing, wherein splicing inhibition led to a redistribution and general reduction over gene bodies. In contrast, little is known of the mechanisms supporting elevated DNA methylation at actively spliced genic locations. Recent evidence associating the de novo DNA methyltransferase Dnmt3b with H3K36me3-rich chromatin raises the possibility that genic DNA methylation is influenced by splicing-associated H3K36me3. Here, we report the generation of an isogenic resource to test the direct impact of splicing on chromatin. A panel of minigenes of varying splicing potential were integrated into a single FRT site for inducible expression. Profiling of H3K36me3 confirmed the established relationship to splicing, wherein levels were directly correlated with splicing efficiency. In contrast, DNA methylation was equivalently detected across the minigene panel, irrespective of splicing and H3K36me3 status. In addition to revealing a degree of independence between genic H3K36me3 and DNA methylation, these findings highlight the generated minigene panel as a flexible platform for the query of splicing-dependent chromatin modifications.
Collapse
Affiliation(s)
- Kyster K. Nanan
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Cody Ocheltree
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - David Sturgill
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mariana D. Mandler
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Maria Prigge
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Garima Varma
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shalini Oberdoerffer
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| |
Collapse
|
49
|
Manzano C, Pallero-Baena M, Silva-Navas J, Navarro Neila S, Casimiro I, Casero P, Garcia-Mina JM, Baigorri R, Rubio L, Fernandez JA, Norris M, Ding Y, Moreno-Risueno MA, Del Pozo JC. A light-sensitive mutation in Arabidopsis LEW3 reveals the important role of N-glycosylation in root growth and development. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:5103-5116. [PMID: 29106622 DOI: 10.1093/jxb/erx324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Plant roots have the potential capacity to grow almost indefinitely if meristematic and lateral branching is sustained. In a genetic screen we identified an Arabidopsis mutant showing limited root growth (lrg1) due to defects in cell division and elongation in the root meristem. Positional cloning determined that lrg1 affects an alpha-1,2-mannosyltransferase gene, LEW3, involved in protein N-glycosylation. The lrg1 mutation causes a synonymous substitution that alters the correct splicing of the fourth intron in LEW3, causing a mix of wild-type and truncated protein. LRG1 RNA missplicing in roots and short root phenotypes in lrg1 are light-intensity dependent. This mutation disrupts a GC-base pair in a three-base-pair stem with a four-nucleotide loop, which seems to be necessary for correct LEW3 RNA splicing. We found that the lrg1 short root phenotype correlates with high levels of reactive oxygen species and low pH in the apoplast. Proteomic analyses of N-glycosylated proteins identified GLU23/PYK10 and PRX34 as N-glycosylation targets of LRG1 activity. The lrg1 mutation reduces the positive interaction between Arabidopsis and Serendipita indica. A prx34 mutant showed a significant reduction in root growth, which is additive to lrg1. Taken together our work highlights the important role of N-glycosylation in root growth and development.
Collapse
Affiliation(s)
- Concepción Manzano
- Centro de Biotecnología y Genómica de Plantas (CBGP) INIA-UPM. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Mercedes Pallero-Baena
- Facultad de Ciencias. Dept. de Anatomía, Biología Celular y Zoología. Universidad de Extremadura. 06006-Badajoz, Spain
| | - J Silva-Navas
- Centro de Biotecnología y Genómica de Plantas (CBGP) INIA-UPM. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Sara Navarro Neila
- Centro de Biotecnología y Genómica de Plantas (CBGP) INIA-UPM. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Ilda Casimiro
- Facultad de Ciencias. Dept. de Anatomía, Biología Celular y Zoología. Universidad de Extremadura. 06006-Badajoz, Spain
| | - Pedro Casero
- Facultad de Ciencias. Dept. de Anatomía, Biología Celular y Zoología. Universidad de Extremadura. 06006-Badajoz, Spain
| | - Jose M Garcia-Mina
- Departamento de Biología Ambiental, Grupo BACh. Facultad de Ciencias. Universidad de Navarra31008 Pamplona, Spain
| | - Roberto Baigorri
- Departamento de Biología Ambiental, Grupo BACh. Facultad de Ciencias. Universidad de Navarra 31008 Pamplona, Spain
- Technical and Development Department, Timac Agro-Grupo Roullier, c/Barrio Féculas s/n, 31580 Lodosa, Navarra, Spain
| | - Lourdes Rubio
- Departamento de Biología Vegetal (Fisiología Vegetal). Facultad de Ciencias. Universidad de Málaga. Campus de Teatinos S/N. 29071 Málaga, Spain
| | - Jose A Fernandez
- Departamento de Biología Vegetal (Fisiología Vegetal). Facultad de Ciencias. Universidad de Málaga. Campus de Teatinos S/N. 29071 Málaga, Spain
| | - Matthew Norris
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich, UK
| | - Yiliang Ding
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich, UK
| | - Miguel A Moreno-Risueno
- Centro de Biotecnología y Genómica de Plantas (CBGP) INIA-UPM. Universidad Politécnica de Madrid. Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Juan C Del Pozo
- Centro de Biotecnología y Genómica de Plantas (CBGP) INIA-UPM. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain
| |
Collapse
|
50
|
Yeh CS, Chang SL, Chen JH, Wang HK, Chou YC, Wang CH, Huang SH, Larson A, Pleiss JA, Chang WH, Chang TH. The conserved AU dinucleotide at the 5' end of nascent U1 snRNA is optimized for the interaction with nuclear cap-binding-complex. Nucleic Acids Res 2017; 45:9679-9693. [PMID: 28934473 PMCID: PMC5766165 DOI: 10.1093/nar/gkx608] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 07/05/2017] [Indexed: 11/13/2022] Open
Abstract
Splicing is initiated by a productive interaction between the pre-mRNA and the U1 snRNP, in which a short RNA duplex is established between the 5' splice site of a pre-mRNA and the 5' end of the U1 snRNA. A long-standing puzzle has been why the AU dincucleotide at the 5'-end of the U1 snRNA is highly conserved, despite the absence of an apparent role in the formation of the duplex. To explore this conundrum, we varied this AU dinucleotide into all possible permutations and analyzed the resulting molecular consequences. This led to the unexpected findings that the AU dinucleotide dictates the optimal binding of cap-binding complex (CBC) to the 5' end of the nascent U1 snRNA, which ultimately influences the utilization of U1 snRNP in splicing. Our data also provide a structural interpretation as to why the AU dinucleotide is conserved during evolution.
Collapse
Affiliation(s)
- Chung-Shu Yeh
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.,Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | | | - Jui-Hui Chen
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Hsuan-Kai Wang
- Genomics Research Center, Academia Sinica, Taipei, Taiwan.,Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei, Taiwan
| | - Yue-Chang Chou
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | | | - Shih-Hsin Huang
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan.,Chemical Biology and Molecular Biophysics program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
| | - Amy Larson
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Jeffrey A Pleiss
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Wei-Hau Chang
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
| | - Tien-Hsien Chang
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.,Genomics Research Center, Academia Sinica, Taipei, Taiwan
| |
Collapse
|