1
|
Peyda P, Lin CH, Onwuzurike K, Black DL. The Rbfox1/LASR complex controls alternative pre-mRNA splicing by recognition of multi-part RNA regulatory modules. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.12.603345. [PMID: 39071271 PMCID: PMC11275806 DOI: 10.1101/2024.07.12.603345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
The Rbfox proteins regulate alternative pre-mRNA splicing by binding to the RNA element GCAUG. In the nucleus, most of Rbfox is bound to LASR, a complex of RNA-binding proteins that recognize additional RNA motifs. However, it remains unclear how the different subunits of the Rbfox/LASR complex act together to bind RNA and regulate splicing. We used a nuclease-protection assay to map the transcriptome-wide footprints of Rbfox1/LASR on nascent cellular RNA. In addition to GCAUG, Rbfox1/LASR binds RNA containing motifs for LASR subunits hnRNPs M, H/F, C, and Matrin3. These elements are often arranged in tandem, forming multi-part modules of RNA motifs. To distinguish contact sites of Rbfox1 from the LASR subunits, we analyzed a mutant Rbfox1(F125A) that has lost RNA binding but remains associated with LASR. Rbfox1(F125A)/LASR complexes no longer interact with GCAUG but retain binding to RNA elements for LASR. Splicing analyses reveal that in addition to activating exons through adjacent GCAUG elements, Rbfox can also stimulate exons near binding sites for LASR subunits. Mini-gene experiments demonstrate that these diverse elements produce a combined regulatory effect on a target exon. These findings illuminate how a complex of RNA-binding proteins can decode combinatorial splicing regulatory signals by recognizing groups of tandem RNA elements.
Collapse
|
2
|
Yao Y, Sun H, Chen Y, Tian L, Huang D, Liu C, Zhou Y, Wang Y, Wen Z, Yang B, Chen X, Pei R. RBM24 inhibits the translation of SARS-CoV-2 polyproteins by targeting the 5'-untranslated region. Antiviral Res 2023; 209:105478. [PMID: 36464077 PMCID: PMC9712144 DOI: 10.1016/j.antiviral.2022.105478] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 11/26/2022] [Accepted: 11/30/2022] [Indexed: 12/03/2022]
Abstract
SARS-CoV-2 is a betacoronavirus with single-stranded positive-sense RNA, which is a serious global threat to human health. Understanding the molecular mechanism of viral replication is crucial for the development of antiviral drugs. The synthesis of viral polyproteins is a crucial step in viral progression. The synthesis of viral polyproteins in coronaviruses is regulated by the 5'-untranslated region (UTR); however, the detailed regulatory mechanism needs further investigation. The present study demonstrated that the RNA binding protein, RBM24, interacts with the RNA genome of SARS-CoV-2 via its RNA recognition submotifs (RNPs). The findings revealed that RBM24 recognizes and binds to the GUGUG element at stem-loop 4 (SL4) in the 5'-UTR of SARS-CoV-2. The interaction between RBM24 and 5'-UTR prevents 80S ribosome assembly, which in turn inhibits polyproteins translation and the replication of SARS-CoV-2. Notably, other RNA viruses, including SARS-CoV, MERS-CoV, Ebolavirus, rhinovirus, West Nile virus, Zika virus, Japanese encephalitis virus, yellow fever virus, hepatitis C virus, and human immunodeficiency virus-1 also contain one or several G(U/C/A)GUG sequences in the 5'-UTR, which is also targeted by RBM24. In conclusion, the present study demonstrated that RBM24 functions by interacting with the 5'-UTR of SARS-CoV-2 RNA, and elucidated that RBM24 could be a host restriction factor for SARS-CoV-2 and other RNA viruses.
Collapse
Affiliation(s)
- Yongxuan Yao
- Joint Center of Translational Precision Medicine, Guangzhou Institute of Pediatrics, Guangzhou Women and Children Medical Center, Guangzhou, 510623, China,State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Hao Sun
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yingshan Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lingqian Tian
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Dan Huang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Canyu Liu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yuan Zhou
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Yun Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Zhe Wen
- Joint Center of Translational Precision Medicine, Guangzhou Institute of Pediatrics, Guangzhou Women and Children Medical Center, Guangzhou, 510623, China
| | - Bo Yang
- Joint Center of Translational Precision Medicine, Guangzhou Institute of Pediatrics, Guangzhou Women and Children Medical Center, Guangzhou, 510623, China,State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China,Corresponding author. Joint Center of Translational Precision Medicine, Guangzhou Institute of Pediatrics, Guangzhou Women and Children Medical Center, Guangzhou, 510623, China
| | - Xinwen Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China,Guangzhou Laboratory, Guangzhou, 510320, China,Corresponding author. State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Rongjuan Pei
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China,Corresponding author
| |
Collapse
|
3
|
Nakura T, Ozoe A, Narita Y, Matsuo M, Hakuno F, Kataoka N, Takahashi SI. Rbfox2 mediates exon 11 inclusion in insulin receptor pre-mRNA splicing in hepatoma cells. Biochimie 2021; 187:25-32. [PMID: 34022289 DOI: 10.1016/j.biochi.2021.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/10/2021] [Accepted: 05/14/2021] [Indexed: 11/27/2022]
Abstract
Insulin receptor (IR) pre-mRNA undergoes alternative splicing that produces two isoforms, IR-A and IR-B. The ratio of IR-A to IR-B varies among tissues, which strongly suggests that IR mRNA alternative splicing is regulated in a tissue-specific manner. However, the precise molecular mechanism for IR alternative splicing remains to be elucidated, especially in liver. In this study, we have analyzed IR alternative splicing mechanism by preparing a mini-gene splicing reporter with rat genomic DNA. The splicing reporter that contains exon 11 and its flanking intronic sequences could reproduce alternative splicing pattern in rat hepatoma H4IIE cells. Introducing several deletions in introns of the reporter revealed that intron 11 contains the region near exon 11 essential to promote exon 11 inclusion. This region contains an UGCAUG sequence, a specific binding site for the Rbfox splicing regulator, and mutation in this sequence results in exon 11 skipping. Furthermore, RbFox2 knockdown in H4IIE cells enhanced exon 11 skipping of endogenous IR pre-mRNA. Lastly mutations in the SRSF3 binding site of exon11 together with the Rbfox2 binding site completely abolished exon 11 inclusion with a mini-gene reporter pre-mRNA. Our results indicate that RbFox2 and SRSF3 proteins mediate exon 11 inclusion in rat hepatoma cells.
Collapse
Affiliation(s)
- Takahito Nakura
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Atsufumi Ozoe
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuka Narita
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Masafumi Matsuo
- KNC Department of Nucleic Acid Drug Discovery, Faculty of Rehabilitation, Kobe Gakuin University, Kobe, Japan
| | - Fumihiko Hakuno
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Naoyuki Kataoka
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan; Laboratory of Cellular Biochemistry, Department of Animal Resource Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Japan.
| | - Shin-Ichiro Takahashi
- Laboratory of Cell Regulation, Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan.
| |
Collapse
|
4
|
Muraoka S, Fukumura K, Hayashi M, Kataoka N, Mayeda A, Kaida D. Rbm38 Reduces the Transcription Elongation Defect of the SMEK2 Gene Caused by Splicing Deficiency. Int J Mol Sci 2020; 21:ijms21228799. [PMID: 33233740 PMCID: PMC7699959 DOI: 10.3390/ijms21228799] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/14/2020] [Accepted: 11/19/2020] [Indexed: 11/30/2022] Open
Abstract
Pre-mRNA splicing is an essential mechanism for ensuring integrity of the transcriptome in eukaryotes. Therefore, splicing deficiency might cause a decrease in functional proteins and the production of nonfunctional, aberrant proteins. To prevent the production of such aberrant proteins, eukaryotic cells have several mRNA quality control mechanisms. In addition to the known mechanisms, we previously found that transcription elongation is attenuated to prevent the accumulation of pre-mRNA under splicing-deficient conditions. However, the detailed molecular mechanism behind the defect in transcription elongation remains unknown. Here, we showed that the RNA binding protein Rbm38 reduced the transcription elongation defect of the SMEK2 gene caused by splicing deficiency. This reduction was shown to require the N- and C-terminal regions of Rbm38, along with an important role being played by the RNA-recognition motif of Rbm38. These findings advance our understanding of the molecular mechanism of the transcription elongation defect caused by splicing deficiency.
Collapse
Affiliation(s)
- Shintaro Muraoka
- Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; (S.M.); (M.H.)
| | - Kazuhiro Fukumura
- Division of Gene Expression Mechanism, Institute for Comprehensive Medical Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan; (K.F.); (A.M.)
| | - Megumi Hayashi
- Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; (S.M.); (M.H.)
| | - Naoyuki Kataoka
- Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan;
| | - Akila Mayeda
- Division of Gene Expression Mechanism, Institute for Comprehensive Medical Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan; (K.F.); (A.M.)
| | - Daisuke Kaida
- Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan; (S.M.); (M.H.)
- Correspondence:
| |
Collapse
|
5
|
Begg BE, Jens M, Wang PY, Minor CM, Burge CB. Concentration-dependent splicing is enabled by Rbfox motifs of intermediate affinity. Nat Struct Mol Biol 2020; 27:901-912. [PMID: 32807990 PMCID: PMC7554199 DOI: 10.1038/s41594-020-0475-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 07/01/2020] [Indexed: 12/15/2022]
Abstract
The Rbfox family of splicing factors regulate alternative splicing during animal development and in disease, impacting thousands of exons in the maturing brain, heart, and muscle. Rbfox proteins have long been known to bind to the RNA sequence GCAUG with high affinity, but just half of Rbfox binding sites contain a GCAUG motif in vivo. We incubated recombinant RBFOX2 with over 60,000 mouse and human transcriptomic sequences to reveal substantial binding to several moderate-affinity, non-GCAYG sites at a physiologically relevant range of RBFOX concentrations. We find that many of these “secondary motifs” bind Rbfox robustly in cells and that several together can exert regulation comparable to GCAUG in a trichromatic splicing reporter assay. Furthermore, secondary motifs regulate RNA splicing in neuronal development and in neuronal subtypes where cellular Rbfox concentrations are highest, enabling a second wave of splicing changes as Rbfox levels increase.
Collapse
Affiliation(s)
- Bridget E Begg
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Marvin Jens
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Peter Y Wang
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Christine M Minor
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Christopher B Burge
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
6
|
Grifone R, Shao M, Saquet A, Shi DL. RNA-Binding Protein Rbm24 as a Multifaceted Post-Transcriptional Regulator of Embryonic Lineage Differentiation and Cellular Homeostasis. Cells 2020; 9:E1891. [PMID: 32806768 PMCID: PMC7463526 DOI: 10.3390/cells9081891] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/06/2020] [Accepted: 08/07/2020] [Indexed: 12/12/2022] Open
Abstract
RNA-binding proteins control the metabolism of RNAs at all stages of their lifetime. They are critically required for the post-transcriptional regulation of gene expression in a wide variety of physiological and pathological processes. Rbm24 is a highly conserved RNA-binding protein that displays strongly regionalized expression patterns and exhibits dynamic changes in subcellular localization during early development. There is increasing evidence that it acts as a multifunctional regulator to switch cell fate determination and to maintain tissue homeostasis. Dysfunction of Rbm24 disrupts cell differentiation in nearly every tissue where it is expressed, such as skeletal and cardiac muscles, and different head sensory organs, but the molecular events that are affected may vary in a tissue-specific, or even a stage-specific manner. Recent works using different animal models have uncovered multiple post-transcriptional regulatory mechanisms by which Rbm24 functions in key developmental processes. In particular, it represents a major splicing factor in muscle cell development, and plays an essential role in cytoplasmic polyadenylation during lens fiber cell terminal differentiation. Here we review the advances in understanding the implication of Rbm24 during development and disease, by focusing on its regulatory roles in physiological and pathological conditions.
Collapse
Affiliation(s)
- Raphaëlle Grifone
- Developmental Biology Laboratory, CNRS-UMR7622, IBPS, Sorbonne University, 75005 Paris, France; (R.G.); (A.S.)
| | - Ming Shao
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China;
| | - Audrey Saquet
- Developmental Biology Laboratory, CNRS-UMR7622, IBPS, Sorbonne University, 75005 Paris, France; (R.G.); (A.S.)
| | - De-Li Shi
- Developmental Biology Laboratory, CNRS-UMR7622, IBPS, Sorbonne University, 75005 Paris, France; (R.G.); (A.S.)
| |
Collapse
|
7
|
Structural basis for mRNA recognition by human RBM38. Biochem J 2020; 477:161-172. [PMID: 31860021 DOI: 10.1042/bcj20190652] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/17/2019] [Accepted: 12/19/2019] [Indexed: 12/29/2022]
Abstract
RNA-binding protein RBM38 was reported to bind the mRNA of several p53-related genes through its RRM domain and to up-regulate or down-regulate protein translation by increasing mRNA stability or recruitment of other effector proteins. The recognition mechanism, however, for RNA-binding of RBM38 remains unclear. Here, we report the crystal structure of the RRM domain of human RBM38 in complex with a single-stranded RNA. Our structural and biological results revealed that RBM38 recognizes G(U/C/A)GUG sequence single-stranded RNA in a sequence-specific and structure-specific manner. Two phenylalanine stacked with bases of RNA were crucial for RNA binding, and a series of hydrogen bonds between the base atoms of RNA and main-chain or side-chain atoms of RBM38 determine the sequence-specific recognition. Our results revealed the RNA-recognition mechanism of human RBM38 and provided structural information for understanding the RNA-binding property of RBM38.
Collapse
|
8
|
Arribere JA, Kuroyanagi H, Hundley HA. mRNA Editing, Processing and Quality Control in Caenorhabditis elegans. Genetics 2020; 215:531-568. [PMID: 32632025 PMCID: PMC7337075 DOI: 10.1534/genetics.119.301807] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 05/03/2020] [Indexed: 02/06/2023] Open
Abstract
While DNA serves as the blueprint of life, the distinct functions of each cell are determined by the dynamic expression of genes from the static genome. The amount and specific sequences of RNAs expressed in a given cell involves a number of regulated processes including RNA synthesis (transcription), processing, splicing, modification, polyadenylation, stability, translation, and degradation. As errors during mRNA production can create gene products that are deleterious to the organism, quality control mechanisms exist to survey and remove errors in mRNA expression and processing. Here, we will provide an overview of mRNA processing and quality control mechanisms that occur in Caenorhabditis elegans, with a focus on those that occur on protein-coding genes after transcription initiation. In addition, we will describe the genetic and technical approaches that have allowed studies in C. elegans to reveal important mechanistic insight into these processes.
Collapse
Affiliation(s)
| | - Hidehito Kuroyanagi
- Laboratory of Gene Expression, Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8510, Japan, and
| | - Heather A Hundley
- Medical Sciences Program, Indiana University School of Medicine-Bloomington, Indiana 47405
| |
Collapse
|
9
|
Integrative Structural Biology of Protein-RNA Complexes. Structure 2020; 28:6-28. [DOI: 10.1016/j.str.2019.11.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 11/17/2019] [Accepted: 11/27/2019] [Indexed: 12/16/2022]
|
10
|
Lin Y, Tan KT, Liu J, Kong X, Huang Z, Xu XQ. Global profiling of Rbm24 bound RNAs uncovers a multi-tasking RNA binding protein. Int J Biochem Cell Biol 2017; 94:10-21. [PMID: 29104163 DOI: 10.1016/j.biocel.2017.11.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 10/28/2017] [Accepted: 11/02/2017] [Indexed: 11/16/2022]
Abstract
RNA binding proteins serve as critical molecular switches in a multitude of post-transcriptional regulatory processes. In the heart and muscles, the tissue specific RNA binding protein, Rbm24, is known to play important developmental roles via driving different post-transcriptional processes. Nonetheless, the currently identified molecular targets and regulatory pathways seem inadequate to completely explain the observed developmental effects upon Rbm24 knockdown/knockout. Here, by performing RNA Immunoprecipitation and coupling it to microarrays (RIP-Chip), we have generated an atlas of the mRNA binding repertoire of Rbm24. Further functional evaluation of its targets led to the elucidation of novel roles for Rbm24 in post-transcriptional processing, besides its already known roles in regulation of mRNA stability and alternative splicing. Interestingly, Rbm24 is found to cause the destabilization of Chrm2 via binding to an element in the coding region. In addition, Rbm24 is also found to have an uncharacterized role in driving the generation of isoforms with alternative transcriptional start sites. We have, for the first time, demonstrated that Rbm24 is a multi-tasking RNA binding protein capable of regulating its bound targets via a range of mechanisms.
Collapse
Affiliation(s)
- Yu Lin
- The Institute of Stem Cell and Regenerative Medicine, Medical College, Xiamen University, 361000, PR China
| | - Kar Tong Tan
- Cancer Science Institute of Singapore, National University of Singapore, Singapore
| | - Jing Liu
- The Institute of Stem Cell and Regenerative Medicine, Medical College, Xiamen University, 361000, PR China
| | - Xu Kong
- The Institute of Stem Cell and Regenerative Medicine, Medical College, Xiamen University, 361000, PR China
| | - Zhengrong Huang
- Department of Cardiology, The First Affiliated Hospital of Xiamen University, Fujian Province, 361000, PR China.
| | - Xiu Qin Xu
- The Institute of Stem Cell and Regenerative Medicine, Medical College, Xiamen University, 361000, PR China; ShenZhen Research Institute of Xiamen University, PR China.
| |
Collapse
|
11
|
Tan JH, Fraser AG. The combinatorial control of alternative splicing in C. elegans. PLoS Genet 2017; 13:e1007033. [PMID: 29121637 PMCID: PMC5697891 DOI: 10.1371/journal.pgen.1007033] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 11/21/2017] [Accepted: 09/19/2017] [Indexed: 12/31/2022] Open
Abstract
Normal development requires the right splice variants to be made in the right tissues at the right time. The core splicing machinery is engaged in all splicing events, but which precise splice variant is made requires the choice between alternative splice sites—for this to occur, a set of splicing factors (SFs) must recognize and bind to short RNA motifs in the pre-mRNA. In C. elegans, there is known to be extensive variation in splicing patterns across development, but little is known about the targets of each SF or how multiple SFs combine to regulate splicing. Here we combine RNA-seq with in vitro binding assays to study how 4 different C. elegans SFs, ASD-1, FOX-1, MEC-8, and EXC-7, regulate splicing. The 4 SFs chosen all have well-characterised biology and well-studied loss-of-function genetic alleles, and all contain RRM domains. Intriguingly, while the SFs we examined have varied roles in C. elegans development, they show an unexpectedly high overlap in their targets. We also find that binding sites for these SFs occur on the same pre-mRNAs more frequently than expected suggesting extensive combinatorial control of splicing. We confirm that regulation of splicing by multiple SFs is often combinatorial and show that this is functionally significant. We also find that SFs appear to combine to affect splicing in two modes—they either bind in close proximity within the same intron or they appear to bind to separate regions of the intron in a conserved order. Finally, we find that the genes whose splicing are regulated by multiple SFs are highly enriched for genes involved in the cytoskeleton and in ion channels that are key for neurotransmission. Together, this shows that specific classes of genes have complex combinatorial regulation of splicing and that this combinatorial regulation is critical for normal development to occur. Alternative splicing (AS) is a highly regulated process that is crucial for normal development. It requires the core splicing machinery, but the specific choice of splice site during AS is controlled by splicing factors (SFs) such as ELAV or RBFOX proteins that bind to specific sequences in pre-mRNAs to regulate usage of different splice sites. AS varies across the C. elegans life cycle and here we study how diverse SFs combine to regulate AS during C. elegans development. We selected 4 RRM-containing SFs that are all well studied and that have well-characterised loss-of-function genetic alleles. We find that these SFs regulate many of the same targets, and that combinatorial interactions between these SFs affect both individual splicing events and organism-level phenotypes including specific effects on the neuromuscular system. We further show that SFs combine to regulate splicing of an individual pre-mRNA in two distinct modes—either by binding in close proximity or by binding in a defined order on the pre-mRNA. Finally, we find that the genes whose splicing are most likely to be regulated by multiple SFs are genes that are required for the proper function of the neuromuscular system. These genes are also most likely to have changing AS patterns across development, suggesting that their splicing regulation is highly complex and developmentally regulated. Taken together, our data show that the precise splice variant expressed at any point in development is often the outcome of regulation by multiple SFs.
Collapse
Affiliation(s)
- June H. Tan
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, 1 King’s College Circle, Toronto, ON, Canada
| | - Andrew G. Fraser
- The Donnelly Centre, University of Toronto, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, 1 King’s College Circle, Toronto, ON, Canada
- * E-mail:
| |
Collapse
|
12
|
Tourasse NJ, Millet JRM, Dupuy D. Quantitative RNA-seq meta-analysis of alternative exon usage in C. elegans. Genome Res 2017; 27:2120-2128. [PMID: 29089372 PMCID: PMC5741048 DOI: 10.1101/gr.224626.117] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 10/26/2017] [Indexed: 12/16/2022]
Abstract
Almost 20 years after the completion of the C. elegans genome sequence, gene structure annotation is still an ongoing process with new evidence for gene variants still being regularly uncovered by additional in-depth transcriptome studies. While alternative splice forms can allow a single gene to encode several functional isoforms, the question of how much spurious splicing is tolerated is still heavily debated. Here we gathered a compendium of 1682 publicly available C. elegans RNA-seq data sets to increase the dynamic range of detection of RNA isoforms, and obtained robust measurements of the relative abundance of each splicing event. While most of the splicing reads come from reproducibly detected splicing events, a large fraction of purported junctions is only supported by a very low number of reads. We devised an automated curation method that takes into account the expression level of each gene to discriminate robust splicing events from potential biological noise. We found that rarely used splice sites disproportionately come from highly expressed genes and are significantly less conserved in other nematode genomes than splice sites with a higher usage frequency. Our increased detection power confirmed trans-splicing for at least 84% of C. elegans protein coding genes. The genes for which trans-splicing was not observed are overwhelmingly low expression genes, suggesting that the mechanism is pervasive but not fully captured by organism-wide RNA-seq. We generated annotated gene models including quantitative exon usage information for the entire C. elegans genome. This allows users to visualize at a glance the relative expression of each isoform for their gene of interest.
Collapse
Affiliation(s)
- Nicolas J Tourasse
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, Institut Européen de Chimie et Biologie (IECB), 33607 Pessac, France
| | - Jonathan R M Millet
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, Institut Européen de Chimie et Biologie (IECB), 33607 Pessac, France
| | - Denis Dupuy
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, Institut Européen de Chimie et Biologie (IECB), 33607 Pessac, France
| |
Collapse
|
13
|
Ohe K, Yoshida M, Nakano-Kobayashi A, Hosokawa M, Sako Y, Sakuma M, Okuno Y, Usui T, Ninomiya K, Nojima T, Kataoka N, Hagiwara M. RBM24 promotes U1 snRNP recognition of the mutated 5' splice site in the IKBKAP gene of familial dysautonomia. RNA (NEW YORK, N.Y.) 2017; 23:1393-1403. [PMID: 28592461 PMCID: PMC5558909 DOI: 10.1261/rna.059428.116] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 05/25/2017] [Indexed: 06/07/2023]
Abstract
The 5' splice site mutation (IVS20+6T>C) of the inhibitor of κ light polypeptide gene enhancer in B cells, kinase complex-associated protein (IKBKAP) gene in familial dysautonomia (FD) is at the sixth intronic nucleotide of the 5' splice site. It is known to weaken U1 snRNP recognition and result in an aberrantly spliced mRNA product in neuronal tissue, but normally spliced mRNA in other tissues. Aberrantly spliced IKBKAP mRNA abrogates IKK complex-associated protein (IKAP)/elongator protein 1 (ELP1) expression and results in a defect of neuronal cell development in FD. To elucidate the tissue-dependent regulatory mechanism, we screened an expression library of major RNA-binding proteins (RBPs) with our mammalian dual-color splicing reporter system and identified RBM24 as a regulator. RBM24 functioned as a cryptic intronic splicing enhancer binding to an element (IVS20+13-29) downstream from the intronic 5' splice site mutation in the IKBKAP gene and promoted U1 snRNP recognition only to the mutated 5' splice site (and not the wild-type 5' splice site). Our results show that tissue-specific expression of RBM24 can explain the neuron-specific aberrant splicing of IKBKAP exon 20 in familial dysautonomia, and that ectopic expression of RBM24 in neuronal tissue could be a novel therapeutic target of the disease.
Collapse
Affiliation(s)
- Kenji Ohe
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
- Training Program of Leaders for Integrated Medical System for Fruitful Healthy-Longevity Society (LIMS), Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Mayumi Yoshida
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Akiko Nakano-Kobayashi
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Motoyasu Hosokawa
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yukiya Sako
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Maki Sakuma
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yukiko Okuno
- Medical Research Support Center, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Tomomi Usui
- Laboratory of Gene Expression, School of Biomedical Science, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Kensuke Ninomiya
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Takayuki Nojima
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | - Naoyuki Kataoka
- Laboratory for Malignancy Control Research, Medical Innovation Center, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507, Japan
- Laboratory of Cell Regulation, Departments of Applied Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Masatoshi Hagiwara
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| |
Collapse
|
14
|
Wani S, Kuroyanagi H. An emerging model organism Caenorhabditis elegans for alternative pre-mRNA processing in vivo. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 8. [PMID: 28703462 DOI: 10.1002/wrna.1428] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 05/02/2017] [Accepted: 05/02/2017] [Indexed: 12/13/2022]
Abstract
A nematode Caenorhabditis elegans is an intron-rich organism and up to 25% of its pre-mRNAs are estimated to be alternatively processed. Its compact genomic organization enables construction of fluorescence splicing reporters with intact genomic sequences and visualization of alternative processing patterns of interest in the transparent living animals with single-cell resolution. Genetic analysis with the reporter worms facilitated identification of trans-acting factors and cis-acting elements, which are highly conserved in mammals. Analysis of unspliced and partially spliced pre-mRNAs in vivo raised models for alternative splicing regulation relying on specific order of intron excision. RNA-seq analysis of splicing factor mutants and CLIP-seq analysis of the factors allow global search for target genes in the whole animal. An mRNA surveillance system is not essential for its viability or fertility, allowing analysis of unproductively spliced noncoding mRNAs. These features offer C. elegans as an ideal model organism for elucidating alternative pre-mRNA processing mechanisms in vivo. Examples of isoform-specific functions of alternatively processed genes are summarized. WIREs RNA 2017, 8:e1428. doi: 10.1002/wrna.1428 For further resources related to this article, please visit the WIREs website.
Collapse
Affiliation(s)
- Shotaro Wani
- Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hidehito Kuroyanagi
- Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| |
Collapse
|
15
|
Protein 4.1R Exon 16 3' Splice Site Activation Requires Coordination among TIA1, Pcbp1, and RBM39 during Terminal Erythropoiesis. Mol Cell Biol 2017; 37:MCB.00446-16. [PMID: 28193846 DOI: 10.1128/mcb.00446-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 02/03/2017] [Indexed: 12/18/2022] Open
Abstract
Exon 16 of protein 4.1R encodes a spectrin/actin-binding peptide critical for erythrocyte membrane stability. Its expression during erythroid differentiation is regulated by alternative pre-mRNA splicing. A UUUUCCCCCC motif situated between the branch point and the 3' splice site is crucial for inclusion. We show that the UUUU region and the last three C residues in this motif are necessary for the binding of splicing factors TIA1 and Pcbp1 and that these proteins appear to act in a collaborative manner to enhance exon 16 inclusion. This element also activates an internal exon when placed in a corresponding intronic position in a heterologous reporter. The impact of these two factors is further enhanced by high levels of RBM39, whose expression rises during erythroid differentiation as exon 16 inclusion increases. TIA1 and Pcbp1 associate in a complex containing RBM39, which interacts with U2AF65 and SF3b155 and promotes U2 snRNP recruitment to the branch point. Our results provide a mechanism for exon 16 3' splice site activation in which a coordinated effort among TIA1, Pcbp1, and RBM39 stabilizes or increases U2 snRNP recruitment, enhances spliceosome A complex formation, and facilitates exon definition through RBM39-mediated splicing regulation.
Collapse
|
16
|
Damianov A, Ying Y, Lin CH, Lee JA, Tran D, Vashisht AA, Bahrami-Samani E, Xing Y, Martin KC, Wohlschlegel JA, Black DL. Rbfox Proteins Regulate Splicing as Part of a Large Multiprotein Complex LASR. Cell 2016; 165:606-19. [PMID: 27104978 DOI: 10.1016/j.cell.2016.03.040] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 12/18/2015] [Accepted: 03/22/2016] [Indexed: 12/11/2022]
Abstract
Rbfox proteins control alternative splicing and posttranscriptional regulation in mammalian brain and are implicated in neurological disease. These proteins recognize the RNA sequence (U)GCAUG, but their structures and diverse roles imply a variety of protein-protein interactions. We find that nuclear Rbfox proteins are bound within a large assembly of splicing regulators (LASR), a multimeric complex containing the proteins hnRNP M, hnRNP H, hnRNP C, Matrin3, NF110/NFAR-2, NF45, and DDX5, all approximately equimolar to Rbfox. We show that splicing repression mediated by hnRNP M is stimulated by Rbfox. Virtually all the intron-bound Rbfox is associated with LASR, and hnRNP M motifs are enriched adjacent to Rbfox crosslinking sites in vivo. These findings demonstrate that Rbfox proteins bind RNA with a defined set of cofactors and affect a broader set of exons than previously recognized. The function of this multimeric LASR complex has implications for deciphering the regulatory codes controlling splicing networks.
Collapse
Affiliation(s)
- Andrey Damianov
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Yi Ying
- Molecular Biology Interdepartmental Ph.D. Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Chia-Ho Lin
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ji-Ann Lee
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Diana Tran
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ajay A Vashisht
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Emad Bahrami-Samani
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Yi Xing
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Kelsey C Martin
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - James A Wohlschlegel
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Douglas L Black
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
| |
Collapse
|
17
|
Yadav DK, Lukavsky PJ. NMR solution structure determination of large RNA-protein complexes. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2016; 97:57-81. [PMID: 27888840 DOI: 10.1016/j.pnmrs.2016.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/04/2016] [Accepted: 10/04/2016] [Indexed: 06/06/2023]
Abstract
Structure determination of RNA-protein complexes is essential for our understanding of the multiple layers of RNA-mediated posttranscriptional regulation of gene expression. Over the past 20years, NMR spectroscopy became a key tool for structural studies of RNA-protein interactions. Here, we review the progress being made in NMR structure determination of large ribonucleoprotein assemblies. We discuss approaches for the design of RNA-protein complexes for NMR structural studies, established and emerging isotope and segmental labeling schemes suitable for large RNPs and how to gain distance restraints from NOEs, PREs and EPR and orientational information from RDCs and SAXS/SANS in such systems. The new combination of NMR measurements with MD simulations and its potential will also be discussed. Application and combination of these various methods for structure determination of large RNPs will be illustrated with three large RNA-protein complexes (>40kDa) and other interesting complexes determined in the past six and a half years.
Collapse
Affiliation(s)
- Deepak Kumar Yadav
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Peter J Lukavsky
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic.
| |
Collapse
|
18
|
Upadhyay SK, Mackereth CD. (1)H, (15)N and (13)C backbone and side chain resonance assignments of the RRM domain from human RBM24. BIOMOLECULAR NMR ASSIGNMENTS 2016; 10:237-240. [PMID: 27002326 DOI: 10.1007/s12104-016-9674-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 03/11/2016] [Indexed: 06/05/2023]
Abstract
Tissue development requires the expression of a regulated subset of genes, and it is becoming clear that the process of alternative splicing also plays an important role in the production of necessary tissue-specific isoforms. However, only a few of these tissue-specific splicing factors in mammals have so far been discovered. One of these factors is the RNA-binding protein RBM24 which has been recently identified as a major regulator of alternative splicing in cardiac and skeletal muscle development. The RBM24 protein contains an RNA recognition motif (RRM) domain that presumably mediates the binding to target pre-mRNA required for regulation of the splicing patterns. Here we report (1)H, (15)N and (13)C chemical shift assignments of the backbone and sidechain atoms for the RRM domain from human RBM24. Secondary chemical shift analysis and relaxation measurement confirm the canonical architecture of the RRM domain. The data will allow for atomic level studies aimed at understanding splicing regulation of target genes in heart and muscle development and investigation into a separate role of RBM24 in modulating mRNA stability of genes involved in the p53 tumor suppressor pathway.
Collapse
Affiliation(s)
| | - Cameron D Mackereth
- Institut Européen de Chimie et Biologie (IECB), University of Bordeaux, 2 rue Robert Escarpit, 33607, Pessac, France
- Inserm, U869, ARNA Laboratory, University of Bordeaux, 33076, Bordeaux, France
| |
Collapse
|
19
|
Determinants of affinity and specificity in RNA-binding proteins. Curr Opin Struct Biol 2016; 38:83-91. [PMID: 27315040 DOI: 10.1016/j.sbi.2016.05.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 05/16/2016] [Accepted: 05/17/2016] [Indexed: 12/21/2022]
Abstract
Emerging data suggest that the mechanisms by which RNA-binding proteins (RBPs) interact with RNA and the rules governing specificity might be substantially more complex than those underlying their DNA-binding counterparts. Even our knowledge of what constitutes the RNA-bound proteome is contentious; recent studies suggest that 10-30% of RBPs contain no known RNA-binding domain. Adding to this situation is a growing disconnect between the avalanche of identified interactions between proteins and long noncoding RNAs and the absence of biophysical data on these interactions. RNA-protein interactions are also at the centre of what might emerge as one of the biggest shifts in thinking about cell and molecular biology this century, following from recent reports of ribonucleoprotein complexes that drive reversible membrane-free phase separation events within the cell. Unexpectedly, low-complexity motifs are important in the formation of these structures. Here we briefly survey recent advances in our understanding of the specificity of RBPs.
Collapse
|
20
|
Tomioka M, Naito Y, Kuroyanagi H, Iino Y. Splicing factors control C. elegans behavioural learning in a single neuron by producing DAF-2c receptor. Nat Commun 2016; 7:11645. [PMID: 27198602 PMCID: PMC4876481 DOI: 10.1038/ncomms11645] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 04/17/2016] [Indexed: 01/18/2023] Open
Abstract
Alternative splicing generates protein diversity essential for neuronal properties. However, the precise mechanisms underlying this process and its relevance to physiological and behavioural functions are poorly understood. To address these issues, we focused on a cassette exon of the Caenorhabditis elegans insulin receptor gene daf-2, whose proper variant expression in the taste receptor neuron ASER is critical for taste-avoidance learning. We show that inclusion of daf-2 exon 11.5 is restricted to specific neuron types, including ASER, and is controlled by a combinatorial action of evolutionarily conserved alternative splicing factors, RBFOX, CELF and PTB families of proteins. Mutations of these factors cause a learning defect, and this defect is relieved by DAF-2c (exon 11.5+) isoform expression only in a single neuron ASER. Our results provide evidence that alternative splicing regulation of a single critical gene in a single critical neuron is essential for learning ability in an organism. Little is known about the molecular mechanisms regulating neuron-specific alternative splicing. Here, the authors identify a combination of RNA-binding proteins regulating neuron-specific expression of the C. elegans insulin receptor isoform DAF-2c and find disrupting these factors leads to learning deficits.
Collapse
Affiliation(s)
- Masahiro Tomioka
- Molecular Genetics Research Laboratory, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yasuki Naito
- Molecular Genetics Research Laboratory, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.,Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hidehito Kuroyanagi
- Laboratory of Gene Expression, Medical Research Institute, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Yuichi Iino
- Molecular Genetics Research Laboratory, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.,Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| |
Collapse
|
21
|
Gracida X, Norris AD, Calarco JA. Regulation of Tissue-Specific Alternative Splicing: C. elegans as a Model System. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 907:229-61. [DOI: 10.1007/978-3-319-29073-7_10] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
22
|
Cieniková Z, Jayne S, Damberger FF, Allain FHT, Maris C. Evidence for cooperative tandem binding of hnRNP C RRMs in mRNA processing. RNA (NEW YORK, N.Y.) 2015; 21:1931-42. [PMID: 26370582 PMCID: PMC4604433 DOI: 10.1261/rna.052373.115] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 07/21/2015] [Indexed: 05/20/2023]
Abstract
The human hnRNP C is a ubiquitous cellular protein involved in mRNA maturation. Recently, we have shown that this protein specifically recognizes uridine (U) pentamers through its single RNA recognition motif (RRM). However, a large fraction of natural RNA targets of hnRNP C consists of much longer contiguous uridine stretches. To understand how these extended sites are recognized, we studied the binding of the RRM to U-tracts of 8-11 bases. In vivo investigation of internal translation activation of unr (upstream of N-ras) mRNA indicates that the conservation of the entire hnRNP C binding site, UC(U)8, is required for hnRNP C-dependent IRES activation. The assays further suggest a synergistic interplay between hnRNP C monomers, dependent on the protein's ability to oligomerize. In vitro spectroscopic and thermodynamic analyses show that isolated RRMs bind to (U)11 oligomers as dimers. Structural modeling of a ternary double-RRM/RNA complex indicates additionally that two RRM copies can be accommodated on the canonical sequence UC(U)8. The proposed tandem RRM binding is in very good agreement with the transcriptome-wide recognition of extended U-tracts by full-length hnRNP C, which displays a cross-linking pattern consistent with a positively cooperative RRM dimer binding model.
Collapse
Affiliation(s)
- Zuzana Cieniková
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Sandrine Jayne
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Fred Franz Damberger
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Frédéric Hai-Trieu Allain
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Christophe Maris
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| |
Collapse
|
23
|
Abstract
RRM-containing proteins are involved in most of the RNA metabolism steps. Their functions are closely related to their mode of RNA recognition, which has been studied by structural biologists for more than 20 years. In this chapter, we report on high-resolution structures of single and multi RRM-RNA complexes to explain the numerous strategies used by these domains to interact specifically with a large repertoire of RNA sequences. We show that multiple variations of their canonical fold can be used to adapt to different single-stranded sequences with a large range of affinities. Furthermore, we describe the consequences on RNA binding of the different structural arrangements found in tandem RRMs and higher order RNPs. Importantly, these structures also reveal with very high accuracy the RNA motifs bound specifically by RRM-containing proteins, which correspond very often to consensus sequences identified with genome-wide approaches. Finally, we show how structural and cellular biology can benefit from each other and pave a way for understanding, defining, and predicting a code of RNA recognition by the RRMs.
Collapse
|
24
|
Mackereth CD. Splicing factor SUP-12 and the molecular complexity of apparent cooperativity. WORM 2015; 3:e991240. [PMID: 26430555 PMCID: PMC4588554 DOI: 10.4161/21624054.2014.991240] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Accepted: 11/20/2014] [Indexed: 12/17/2022]
Abstract
The splicing factor SUP-12 from C. elegans, in combination with either ASD-1 or FOX-1 from the Fox-1 (RBFOX) family, is required for generating a muscle-specific isoform of the fibroblast growth factor receptor EGL-15. Biophysical techniques have revealed the sequence preference for the RNA Recognition Motif (RRM) domain from SUP-12 as well as the structural details of the RNA-bound complex. Detailed genetics have identified a requisite need for the presence of both SUP-12 and ASD-1/FOX-1 to regulate the alternative splicing event, prompting speculation of a cooperative mechanism between these proteins on binding RNA. In contrast, the interplay between SUP-12 and ASD-1 suggests that although the RRM domains from each protein are in direct contact on the egl-15 pre-mRNA, there is no simple contribution of binding cooperativity. Evidence for an independent binding mechanism by SUP-12 and ASD-1 will be discussed, including a model in which both positive and negative contributions are balanced during complex assembly. The ability to monitor tissue-specific alternative splicing in live nematodes will continue to provide a powerful method to test in vivo mechanistic models derived from atomic-level investigation.
Collapse
Affiliation(s)
- Cameron D Mackereth
- Inserm U869; University of Bordeaux; Institut Européen de Chimie et Biologie Pessac ; France
| |
Collapse
|