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Parija M, Prakash S, Krishna BM, Dash S, Mishra SK. SIRT1 mediates breast cancer development and tumorigenesis controlled by estrogen-related receptor β. Breast Cancer 2024; 31:440-455. [PMID: 38421553 DOI: 10.1007/s12282-024-01555-9] [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: 07/05/2023] [Accepted: 02/11/2024] [Indexed: 03/02/2024]
Abstract
Silent mating type information regulation 2 homolog 1 (SIRT1) is a class III histone deacetylase (HDAC) that is NAD + dependent and essential for metabolism, senescence, and cell survival. SIRT1 is overexpressed in several cancers, including breast cancer. SIRT1 is a well-known target gene of the estrogen receptor alpha (ER alpha) and is closely related to ER alpha deacetylation. Transcription factor Estrogen-related receptors (ERRs) share sequence homology with ERs in the DNA-binding domain, therefore, the possibility of sharing target genes between them is high. Our current research aims to gain insight into the function of ERRβ in regulating the activity of SIRT1 during the progression of breast cancer. ER-positive (ER + ve) breast cancer cells and tissues had considerably enhanced SIRT1 expression. Six potential ERRE sites were identified by analysis of the 5' upstream region of SIRT1, and both in vitro and in vivo experiments supported their presence. We found SIRT1 to be up-regulated in ERRβ overexpressed ER + ve breast cancer cells. Furthermore, our findings suggested that ectopic production of ERR and PCAF would increase SIRT1 activity. Our findings also indicated that ectopic production of ERRβ and PCAF increased SIRT1 activity. With sufficient evidence demonstrating the substantial involvement of SIRT1 in cell proliferation, migration, and colony formation capability, we were also able to illustrate the tumorigenic role of SIRT1. Overall, our findings highlight SIRT1's tumorigenic influence on breast cancer and suggest that SIRT1 inhibitors might serve as potential therapeutic drugs for the treatment of breast cancer.
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Affiliation(s)
- Monalisa Parija
- Cancer Biology Lab, Gene Function and Regulation Group, Institute of Life Sciences, Nalco Square, Nadankanan Road, Kalinga Hospital Cross, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana (NCR Delhi), 121001, India
| | - Surya Prakash
- Cancer Biology Lab, Gene Function and Regulation Group, Institute of Life Sciences, Nalco Square, Nadankanan Road, Kalinga Hospital Cross, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana (NCR Delhi), 121001, India
| | - B Madhu Krishna
- Department of Medical Oncology, Beckman Research Institute of City of Hope, Comprehensive Cancer Center and National Medical Center, Duarte, CA, 91010, USA
| | - Sanghamitra Dash
- Cancer Biology Lab, Gene Function and Regulation Group, Institute of Life Sciences, Nalco Square, Nadankanan Road, Kalinga Hospital Cross, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana (NCR Delhi), 121001, India
| | - Sandip K Mishra
- Cancer Biology Lab, Gene Function and Regulation Group, Institute of Life Sciences, Nalco Square, Nadankanan Road, Kalinga Hospital Cross, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India.
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2
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Carrion SA, Michal JJ, Jiang Z. Alternative Transcripts Diversify Genome Function for Phenome Relevance to Health and Diseases. Genes (Basel) 2023; 14:2051. [PMID: 38002994 PMCID: PMC10671453 DOI: 10.3390/genes14112051] [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: 10/13/2023] [Revised: 11/06/2023] [Accepted: 11/07/2023] [Indexed: 11/26/2023] Open
Abstract
Manipulation using alternative exon splicing (AES), alternative transcription start (ATS), and alternative polyadenylation (APA) sites are key to transcript diversity underlying health and disease. All three are pervasive in organisms, present in at least 50% of human protein-coding genes. In fact, ATS and APA site use has the highest impact on protein identity, with their ability to alter which first and last exons are utilized as well as impacting stability and translation efficiency. These RNA variants have been shown to be highly specific, both in tissue type and stage, with demonstrated importance to cell proliferation, differentiation and the transition from fetal to adult cells. While alternative exon splicing has a limited effect on protein identity, its ubiquity highlights the importance of these minor alterations, which can alter other features such as localization. The three processes are also highly interwoven, with overlapping, complementary, and competing factors, RNA polymerase II and its CTD (C-terminal domain) chief among them. Their role in development means dysregulation leads to a wide variety of disorders and cancers, with some forms of disease disproportionately affected by specific mechanisms (AES, ATS, or APA). Challenges associated with the genome-wide profiling of RNA variants and their potential solutions are also discussed in this review.
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Affiliation(s)
| | | | - Zhihua Jiang
- Department of Animal Sciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164-7620, USA; (S.A.C.); (J.J.M.)
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3
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Zukher I, Dujardin G, Sousa-Luís R, Proudfoot NJ. Elongation roadblocks mediated by dCas9 across human genes modulate transcription and nascent RNA processing. Nat Struct Mol Biol 2023; 30:1536-1548. [PMID: 37783853 PMCID: PMC10584677 DOI: 10.1038/s41594-023-01090-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 08/04/2023] [Indexed: 10/04/2023]
Abstract
Non-cleaving Cas9 (dCas9) is widely employed to manipulate specific gene loci, often with scant regard for unintended transcriptional effects. We demonstrate here that dCas9 mediates precise RNA polymerase II transcriptional pausing followed by transcription termination and potential alternative polyadenylation. By contrast, alternative splicing is unaffected, likely requiring more sustained alteration to elongation speed. The effect on transcription is orientation specific, with pausing only being induced when dCas9-associated guide RNA anneals to the non-template strand. Targeting the template strand induces minimal effects on transcription elongation and thus provides a neutral approach to recruit dCas9-linked effector domains to specific gene regions. In essence, we evaluate molecular effects of targeting dCas9 to mammalian transcription units. In so doing, we also provide new information on elongation by RNA polymerase II and coupled pre-mRNA processing.
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Affiliation(s)
- Inna Zukher
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
| | - Gwendal Dujardin
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Rui Sousa-Luís
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Nick J Proudfoot
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
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4
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Shenasa H, Bentley DL. Pre-mRNA splicing and its cotranscriptional connections. Trends Genet 2023; 39:672-685. [PMID: 37236814 PMCID: PMC10524715 DOI: 10.1016/j.tig.2023.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/23/2023] [Accepted: 04/26/2023] [Indexed: 05/28/2023]
Abstract
Transcription of eukaryotic genes by RNA polymerase II (Pol II) yields RNA precursors containing introns that must be spliced out and the flanking exons ligated together. Splicing is catalyzed by a dynamic ribonucleoprotein complex called the spliceosome. Recent evidence has shown that a large fraction of splicing occurs cotranscriptionally as the RNA chain is extruded from Pol II at speeds of up to 5 kb/minute. Splicing is more efficient when it is tethered to the transcription elongation complex, and this linkage permits functional coupling of splicing with transcription. We discuss recent progress that has uncovered a network of connections that link splicing to transcript elongation and other cotranscriptional RNA processing events.
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Affiliation(s)
- Hossein Shenasa
- Department of Biochemistry and Molecular Genetics, RNA Bioscience Initiative, University of Colorado School of Medicine, PO Box 6511, Aurora, CO 80045, USA
| | - David L Bentley
- Department of Biochemistry and Molecular Genetics, RNA Bioscience Initiative, University of Colorado School of Medicine, PO Box 6511, Aurora, CO 80045, USA.
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5
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Makowczenko KG, Jastrzebski JP, Kiezun M, Paukszto L, Dobrzyn K, Smolinska N, Kaminski T. Adaptation of the Porcine Pituitary Transcriptome, Spliceosome and Editome during Early Pregnancy. Int J Mol Sci 2023; 24:ijms24065946. [PMID: 36983019 PMCID: PMC10053595 DOI: 10.3390/ijms24065946] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/15/2023] [Accepted: 03/16/2023] [Indexed: 03/30/2023] Open
Abstract
The physiological mechanisms of the porcine reproduction are relatively well-known. However, transcriptomic changes and the mechanisms accompanying transcription and translation processes in various reproductive organs, as well as their dependence on hormonal status, are still poorly understood. The aim of this study was to gain a principal understanding of alterations within the transcriptome, spliceosome and editome occurring in the pituitary of the domestic pig (Sus scrofa domestica L.), which controls basic physiological processes in the reproductive system. In this investigation, we performed extensive analyses of data obtained by high-throughput sequencing of RNA from the gilts' pituitary anterior lobes during embryo implantation and the mid-luteal phase of the estrous cycle. During analyses, we obtained detailed information on expression changes of 147 genes and 43 long noncoding RNAs, observed 784 alternative splicing events and also found the occurrence of 8729 allele-specific expression sites and 122 RNA editing events. The expression profiles of the selected 16 phenomena were confirmed by PCR or qPCR techniques. As a final result of functional meta-analysis, we acquired knowledge regarding intracellular pathways that induce changes in the processes accompanying transcription and translation regulation, which may induce modifications in the secretory activity of the porcine adenohypophyseal cells.
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Affiliation(s)
- Karol G Makowczenko
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland
| | - Jan P Jastrzebski
- Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland
| | - Marta Kiezun
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland
| | - Lukasz Paukszto
- Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Plac Lodzki 1, 10-719 Olsztyn, Poland
| | - Kamil Dobrzyn
- Department of Zoology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 5, 10-719 Olsztyn, Poland
| | - Nina Smolinska
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland
| | - Tadeusz Kaminski
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland
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6
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Temporal-iCLIP captures co-transcriptional RNA-protein interactions. Nat Commun 2023; 14:696. [PMID: 36755023 PMCID: PMC9908952 DOI: 10.1038/s41467-023-36345-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 01/27/2023] [Indexed: 02/10/2023] Open
Abstract
Dynamic RNA-protein interactions govern the co-transcriptional packaging of RNA polymerase II (RNAPII)-derived transcripts. Yet, our current understanding of this process in vivo primarily stems from steady state analysis. To remedy this, we here conduct temporal-iCLIP (tiCLIP), combining RNAPII transcriptional synchronisation with UV cross-linking of RNA-protein complexes at serial timepoints. We apply tiCLIP to the RNA export adaptor, ALYREF; a component of the Nuclear Exosome Targeting (NEXT) complex, RBM7; and the nuclear cap binding complex (CBC). Regardless of function, all tested factors interact with nascent RNA as it exits RNAPII. Moreover, we demonstrate that the two transesterification steps of pre-mRNA splicing temporally separate ALYREF and RBM7 binding to splicing intermediates, and that exon-exon junction density drives RNA 5'end binding of ALYREF. Finally, we identify underappreciated steps in snoRNA 3'end processing performed by RBM7. Altogether, our data provide a temporal view of RNA-protein interactions during the early phases of transcription.
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7
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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. [PMCID: PMC9664736 DOI: 10.1186/s12859-022-05041-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022] Open
Abstract
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.
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8
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Xing C, Zeng Z, Li Y, Gong B, Shen W, Shah R, Yan L, Du H, Meng A. Regulatory factor identification for nodal genes in zebrafish by causal inference. Front Cell Dev Biol 2022; 10:1047363. [DOI: 10.3389/fcell.2022.1047363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 10/04/2022] [Indexed: 11/13/2022] Open
Abstract
Activation of nodal genes is critical for mesoderm and endoderm induction. Our previous study reported that zebrafish nodal genes ndr1/squint and ndr2/cyclops are coordinately regulated by maternal Eomesa, Hwa-activated β-catenin (Hwa/β-catenin) signaling, and Nodal autoregulation (Nodal/Smad2) signaling. However, the exact contribution and underlying mechanisms are still elusive. Here, we applied “causal inference” to evaluate the causal between the independent and dependent variables, and we found that Hwa/β-catenin and Smad2 are the cause of ndr1 activation, while Eomesa is the cause of ndr2 activation. Mechanistically, the different cis-regulatory regions of ndr1 and ndr2 bound by Eomesa, β-catenin, and Smad2 were screened out via ChIP-qPCR and verified by the transgene constructs. The marginal GFP expression driven by ndr1 transgenesis could be diminished without both maternal Eomesa and Hwa/β-catenin, while Eomesa, not β-catenin, could bind and activate ndr2 demonstrated by ndr2 transgenesis. Thus, the distinct regulation of ndr1/ndr2 relies on different cis-regulatory regions.
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9
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Marasco LE, Dujardin G, Sousa-Luís R, Liu YH, Stigliano JN, Nomakuchi T, Proudfoot NJ, Krainer AR, Kornblihtt AR. Counteracting chromatin effects of a splicing-correcting antisense oligonucleotide improves its therapeutic efficacy in spinal muscular atrophy. Cell 2022; 185:2057-2070.e15. [PMID: 35688133 DOI: 10.1016/j.cell.2022.04.031] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 03/17/2022] [Accepted: 04/26/2022] [Indexed: 11/19/2022]
Abstract
Spinal muscular atrophy (SMA) is a motor-neuron disease caused by mutations of the SMN1 gene. The human paralog SMN2, whose exon 7 (E7) is predominantly skipped, cannot compensate for the lack of SMN1. Nusinersen is an antisense oligonucleotide (ASO) that upregulates E7 inclusion and SMN protein levels by displacing the splicing repressors hnRNPA1/A2 from their target site in intron 7. We show that by promoting transcriptional elongation, the histone deacetylase inhibitor VPA cooperates with a nusinersen-like ASO to promote E7 inclusion. Surprisingly, the ASO promotes the deployment of the silencing histone mark H3K9me2 on the SMN2 gene, creating a roadblock to RNA polymerase II elongation that inhibits E7 inclusion. By removing the roadblock, VPA counteracts the chromatin effects of the ASO, resulting in higher E7 inclusion without large pleiotropic effects. Combined administration of the nusinersen-like ASO and VPA in SMA mice strongly synergizes SMN expression, growth, survival, and neuromuscular function.
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Affiliation(s)
- Luciano E Marasco
- Universidad de Buenos Aires (UBA), Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular and CONICET-UBA, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), 1428 Buenos Aires, Argentina
| | - Gwendal Dujardin
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Rui Sousa-Luís
- Instituto de Medicina Molecular João Lobo Antunes, University of Lisbon, 1649-028 Lisboa, Portugal
| | - Ying Hsiu Liu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Jose N Stigliano
- Universidad de Buenos Aires (UBA), Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular and CONICET-UBA, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), 1428 Buenos Aires, Argentina
| | - Tomoki Nomakuchi
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Nick J Proudfoot
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Adrian R Krainer
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Alberto R Kornblihtt
- Universidad de Buenos Aires (UBA), Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular and CONICET-UBA, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), 1428 Buenos Aires, Argentina.
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10
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Hinkle ER, Wiedner HJ, Torres EV, Jackson M, Black AJ, Blue RE, Harris SE, Guzman BB, Gentile GM, Lee EY, Tsai YH, Parker J, Dominguez D, Giudice J. Alternative splicing regulation of membrane trafficking genes during myogenesis. RNA (NEW YORK, N.Y.) 2022; 28:523-540. [PMID: 35082143 PMCID: PMC8925968 DOI: 10.1261/rna.078993.121] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
Alternative splicing transitions occur during organ development, and, in numerous diseases, splicing programs revert to fetal isoform expression. We previously found that extensive splicing changes occur during postnatal mouse heart development in genes encoding proteins involved in vesicle-mediated trafficking. However, the regulatory mechanisms of this splicing-trafficking network are unknown. Here, we found that membrane trafficking genes are alternatively spliced in a tissue-specific manner, with striated muscles exhibiting the highest levels of alternative exon inclusion. Treatment of differentiated muscle cells with chromatin-modifying drugs altered exon inclusion in muscle cells. Examination of several RNA-binding proteins revealed that the poly-pyrimidine tract binding protein 1 (PTBP1) and quaking regulate splicing of trafficking genes during myogenesis, and that removal of PTBP1 motifs prevented PTBP1 from binding its RNA target. These findings enhance our understanding of developmental splicing regulation of membrane trafficking proteins which might have implications for muscle disease pathogenesis.
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Affiliation(s)
- Emma R Hinkle
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Curriculum in Genetics and Molecular Biology (GMB), The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Hannah J Wiedner
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Curriculum in Genetics and Molecular Biology (GMB), The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Eduardo V Torres
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Micaela Jackson
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Adam J Black
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - R Eric Blue
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Sarah E Harris
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Bryan B Guzman
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Gabrielle M Gentile
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Curriculum in Genetics and Molecular Biology (GMB), The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Eunice Y Lee
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Yi-Hsuan Tsai
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Joel Parker
- Curriculum in Genetics and Molecular Biology (GMB), The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Daniel Dominguez
- Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Jimena Giudice
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Curriculum in Genetics and Molecular Biology (GMB), The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- McAllister Heart Institute, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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11
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Chen L, Xu W, Liu K, Jiang Z, Han Y, Jin H, Zhang L, Shen W, Jia S, Sun Q, Meng A. 5' Half of specific tRNAs feeds back to promote corresponding tRNA gene transcription in vertebrate embryos. SCIENCE ADVANCES 2021; 7:eabh0494. [PMID: 34797706 PMCID: PMC8604414 DOI: 10.1126/sciadv.abh0494] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
5′tRFls are small transfer RNA (tRNA) fragments derived from 5′ half of mature tRNAs. However, it is unknown whether 5′tRFls could feed back to regulate tRNA biogenesis. Here, we show that 5′tRFlGly/GCC and 5′tRFlGlu/CTC function to promote transcription of corresponding tRNA genes and are essential for vertebrate early embryogenesis. During zebrafish embryogenesis, dynamics of 5′tRFlGly/GCC and 5′tRFlGlu/CTC levels correlates with that of tRNAGly/GCC and tRNAGlu/CTC levels. Morpholino-mediated knockdown of 5′tRFlGly/GCC or 5′tRFlGlu/CTC down-regulates tRNAGly/GCC or tRNAGlu/CTC levels, respectively, and causes embryonic lethality that is efficiently rescued by coinjection of properly refolded corresponding tRNA. In zebrafish embryos, tRNA:DNA and 5′tRFl:DNA hybrids commonly exist on the template strand of tRNA genes. Mechanistically, unstable 5′tRFl:DNA hybrid may prevent the formation of transcriptionally inhibitory stable tRNA:DNA hybrids on the same tRNA loci so as to facilitate tRNA gene transcription. The uncovered mechanism may be implicated in other physiological and pathological processes.
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Affiliation(s)
- Luxi Chen
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Wei Xu
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
- The Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Kunpeng Liu
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
- The Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zheng Jiang
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yang Han
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Hongbin Jin
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lin Zhang
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Weimin Shen
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shunji Jia
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qianwen Sun
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
- The Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Anming Meng
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
- Guangzhou Laboratory, Guangzhou 510320, Guangdong Province, China
- Corresponding author.
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12
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Maudlin IE, Beggs JD. Conditional depletion of transcriptional kinases Ctk1 and Bur1 and effects on co-transcriptional spliceosome assembly and pre-mRNA splicing. RNA Biol 2021; 18:782-793. [PMID: 34705599 PMCID: PMC8782173 DOI: 10.1080/15476286.2021.1991673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/21/2021] [Indexed: 11/28/2022] Open
Abstract
From yeast to humans, pre-mRNA splicing occurs mainly co-transcriptionally, with splicing and transcription functionally coupled such that they influence one another. The recruitment model of co-transcriptional splicing proposes that core members of the transcription elongation machinery have the potential to influence co-transcriptional spliceosome assembly and pre-mRNA splicing. Here, we tested whether the transcription elongation kinases Bur1 and Ctk1 affect co-transcriptional spliceosome assembly and pre-mRNA splicing in the budding yeast Saccharomyces cerevisiae. In S. cerevisiae, Ctk1 is the major kinase that phosphorylates serine 2 of the carboxy-terminal domain of the largest subunit of RNA polymerase II, whilst Bur1 augments the kinase activity of Ctk1 and is the major kinase for elongation factor Spt5. We used the auxin-inducible degron system to conditionally deplete Bur1 and Ctk1 kinases, and investigated the effects on co-transcriptional spliceosome assembly and pre-mRNA splicing. Depletion of Ctk1 effectively reduced phosphorylation of serine 2 of the carboxy-terminal domain but did not impact co-transcriptional spliceosome assembly or pre-mRNA splicing. In striking contrast, depletion of Bur1 did not reduce phosphorylation of serine 2 of the carboxy-terminal domain, but reduced Spt5 phosphorylation and enhanced co-transcriptional spliceosome assembly and pre-mRNA splicing, suggesting a role for this kinase in modulating co-transcriptional splicing.
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Affiliation(s)
- Isabella E. Maudlin
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Jean D. Beggs
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
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13
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Laliotis GI, Chavdoula E, Paraskevopoulou MD, Kaba A, La Ferlita A, Singh S, Anastas V, Nair KA, Orlacchio A, Taraslia V, Vlachos I, Capece M, Hatzigeorgiou A, Palmieri D, Tsatsanis C, Alaimo S, Sehgal L, Carbone DP, Coppola V, Tsichlis PN. AKT3-mediated IWS1 phosphorylation promotes the proliferation of EGFR-mutant lung adenocarcinomas through cell cycle-regulated U2AF2 RNA splicing. Nat Commun 2021; 12:4624. [PMID: 34330897 PMCID: PMC8324843 DOI: 10.1038/s41467-021-24795-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 03/05/2021] [Indexed: 02/06/2023] Open
Abstract
AKT-phosphorylated IWS1 regulates alternative RNA splicing via a pathway that is active in lung cancer. RNA-seq studies in lung adenocarcinoma cells lacking phosphorylated IWS1, identified a exon 2-deficient U2AF2 splice variant. Here, we show that exon 2 inclusion in the U2AF2 mRNA is a cell cycle-dependent process that is regulated by LEDGF/SRSF1 splicing complexes, whose assembly is controlled by the IWS1 phosphorylation-dependent deposition of histone H3K36me3 marks in the body of target genes. The exon 2-deficient U2AF2 mRNA encodes a Serine-Arginine-Rich (RS) domain-deficient U2AF65, which is defective in CDCA5 pre-mRNA processing. This results in downregulation of the CDCA5-encoded protein Sororin, a phosphorylation target and regulator of ERK, G2/M arrest and impaired cell proliferation and tumor growth. Analysis of human lung adenocarcinomas, confirmed activation of the pathway in EGFR-mutant tumors and showed that pathway activity correlates with tumor stage, histologic grade, metastasis, relapse after treatment, and poor prognosis.
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Affiliation(s)
- Georgios I Laliotis
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA.
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA.
- School of Medicine, University of Crete, Heraklion, Crete, Greece.
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Evangelia Chavdoula
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
| | | | - Abdul Kaba
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
| | - Alessandro La Ferlita
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
- Department of Clinical and Experimental Medicine, Bioinformatics Unit, University of Catania, Catania, Italy
| | - Satishkumar Singh
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
- Department of Medicine, Division of Hematology, The Ohio State University, Columbus, OH, USA
| | - Vollter Anastas
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
- Tufts Graduate School of Biomedical Sciences, Program in Genetics, Boston, MA, USA
| | - Keith A Nair
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
| | - Arturo Orlacchio
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
| | - Vasiliki Taraslia
- Molecular Oncology Research Institute, Tufts Medical Center, Boston, MA, USA
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Ioannis Vlachos
- DIANA-Lab, Hellenic Pasteur Institute, Athens, Greece
- Department Of Pathology, Beth Israel-Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Marina Capece
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
| | | | - Dario Palmieri
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
| | - Christos Tsatsanis
- School of Medicine, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
| | - Salvatore Alaimo
- Department of Clinical and Experimental Medicine, Bioinformatics Unit, University of Catania, Catania, Italy
| | - Lalit Sehgal
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
- Department of Medicine, Division of Hematology, The Ohio State University, Columbus, OH, USA
| | - David P Carbone
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
- Department of Internal Medicine, Division of Medical Oncology, The Ohio State University Medical Center, Columbus, OH, USA
| | - Vincenzo Coppola
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA
| | - Philip N Tsichlis
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA.
- The Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, OH, USA.
- Tufts Graduate School of Biomedical Sciences, Program in Genetics, Boston, MA, USA.
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14
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Courchaine EM, Barentine AES, Straube K, Lee DR, Bewersdorf J, Neugebauer KM. DMA-tudor interaction modules control the specificity of in vivo condensates. Cell 2021; 184:3612-3625.e17. [PMID: 34115980 DOI: 10.1016/j.cell.2021.05.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 12/21/2020] [Accepted: 05/07/2021] [Indexed: 12/31/2022]
Abstract
Biomolecular condensation is a widespread mechanism of cellular compartmentalization. Because the "survival of motor neuron protein" (SMN) is implicated in the formation of three different membraneless organelles (MLOs), we hypothesized that SMN promotes condensation. Unexpectedly, we found that SMN's globular tudor domain was sufficient for dimerization-induced condensation in vivo, whereas its two intrinsically disordered regions (IDRs) were not. Binding to dimethylarginine (DMA) modified protein ligands was required for condensate formation by the tudor domains in SMN and at least seven other fly and human proteins. Remarkably, asymmetric versus symmetric DMA determined whether two distinct nuclear MLOs-gems and Cajal bodies-were separate or "docked" to one another. This substructure depended on the presence of either asymmetric or symmetric DMA as visualized with sub-diffraction microscopy. Thus, DMA-tudor interaction modules-combinations of tudor domains bound to their DMA ligand(s)-represent versatile yet specific regulators of MLO assembly, composition, and morphology.
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Affiliation(s)
- Edward M Courchaine
- Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Andrew E S Barentine
- Cell Biology, Yale University, New Haven, CT 06520, USA; Biomedical Engineering, Yale University, New Haven, CT 06520, USA
| | - Korinna Straube
- Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | | | - Joerg Bewersdorf
- Cell Biology, Yale University, New Haven, CT 06520, USA; Biomedical Engineering, Yale University, New Haven, CT 06520, USA
| | - Karla M Neugebauer
- Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA; Cell Biology, Yale University, New Haven, CT 06520, USA.
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15
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Zhang J, Goel A, Zhu L. Identification of Novel Alternative Splicing Events Associated With Tumorigenesis, Protein Modification, and Immune Microenvironment in Early-Onset Gastric Cancer. Front Oncol 2021; 11:640272. [PMID: 34168979 PMCID: PMC8217769 DOI: 10.3389/fonc.2021.640272] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 05/10/2021] [Indexed: 01/22/2023] Open
Abstract
Background Alternative splicing (AS), e.g. the tandem alternative polyadenylation (TAPA), has emerged as major post-transcriptional modification events in human disease. However, the roles of the AS and TAPA in early-onset gastric cancer (EOGC) have not been revealed. Methods The global AS profiles of 80 EOGC patients were analyzed. The EOGC-specific AS events (ESASs) were identified in both the EOGC and adjacent non-tumor tissues. The functional enrichment analysis, Splicing network, Alternative Polyadenylation (APA) core factor network, and cell abundancy analysis were performed. Furthermore, the landscapes of the AS events in the varied subtypes of the EOGC patients were evaluated. Results Overall, 66,075 AS events and 267 ESASs were identified in the EOGC. Furthermore, 4809 genes and 6152 gene isoforms were found to be aberrantly expressed in the EOGC. The Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genome (KEGG) pathway analyses showed that the significant pathway alterations might exist in these AS events, genes, and gene isoforms. Moreover, the Protein-protein interaction (PPI) network analysis revealed that the UBC, NEK2, EPHB2, and DCTN1 genes were the hub genes in the AS events in the EOGC. The immune cell infiltration analysis indicated a correlation between the AS events and the cancer immune microenvironment. The distribution of the AS events in varied EOGC subtypes, protein phosphorylation and glycosylation was uneven. Conclusion The study highlighted the vital roles of the AS in the EOGC, including modulating the specific protein modification and reshaping the cancer immune microenvironment, and yielded new insights into the diagnosis of the EOGC as well as cancer treatment.
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Affiliation(s)
- Jian Zhang
- Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy, Texas A&M University, College Station, TX, United States
| | - Ajay Goel
- Beckman Research Institute, City of Hope Comprehensive Cancer Center, Biomedical Research Center, Monrovia, CA, United States
| | - Lin Zhu
- Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy, Texas A&M University, College Station, TX, United States
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16
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Rambout X, Maquat LE. The nuclear cap-binding complex as choreographer of gene transcription and pre-mRNA processing. Genes Dev 2021; 34:1113-1127. [PMID: 32873578 PMCID: PMC7462061 DOI: 10.1101/gad.339986.120] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In this review, Rambout and Maquat discuss known roles of the nuclear cap-binding complex (CBC) during the transcription of genes that encode proteins, stitching together past studies from diverse groups to describe the continuum of CBC-mediated checks and balances in eukaryotic cells. The largely nuclear cap-binding complex (CBC) binds to the 5′ caps of RNA polymerase II (RNAPII)-synthesized transcripts and serves as a dynamic interaction platform for a myriad of RNA processing factors that regulate gene expression. While influence of the CBC can extend into the cytoplasm, here we review the roles of the CBC in the nucleus, with a focus on protein-coding genes. We discuss differences between CBC function in yeast and mammals, covering the steps of transcription initiation, release of RNAPII from pausing, transcription elongation, cotranscriptional pre-mRNA splicing, transcription termination, and consequences of spurious transcription. We describe parameters known to control the binding of generic or gene-specific cofactors that regulate CBC activities depending on the process(es) targeted, illustrating how the CBC is an ever-changing choreographer of gene expression.
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Affiliation(s)
- Xavier Rambout
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA.,Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
| | - Lynne E Maquat
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA.,Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
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17
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Caizzi L, Monteiro-Martins S, Schwalb B, Lysakovskaia K, Schmitzova J, Sawicka A, Chen Y, Lidschreiber M, Cramer P. Efficient RNA polymerase II pause release requires U2 snRNP function. Mol Cell 2021; 81:1920-1934.e9. [PMID: 33689748 DOI: 10.1016/j.molcel.2021.02.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 01/07/2021] [Accepted: 02/10/2021] [Indexed: 12/21/2022]
Abstract
Transcription by RNA polymerase II (Pol II) is coupled to pre-mRNA splicing, but the underlying mechanisms remain poorly understood. Co-transcriptional splicing requires assembly of a functional spliceosome on nascent pre-mRNA, but whether and how this influences Pol II transcription remains unclear. Here we show that inhibition of pre-mRNA branch site recognition by the spliceosome component U2 snRNP leads to a widespread and strong decrease in new RNA synthesis from human genes. Multiomics analysis reveals that inhibition of U2 snRNP function increases the duration of Pol II pausing in the promoter-proximal region, impairs recruitment of the pause release factor P-TEFb, and reduces Pol II elongation velocity at the beginning of genes. Our results indicate that efficient release of paused Pol II into active transcription elongation requires the formation of functional spliceosomes and that eukaryotic mRNA biogenesis relies on positive feedback from the splicing machinery to the transcription machinery.
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Affiliation(s)
- Livia Caizzi
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Sara Monteiro-Martins
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Björn Schwalb
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Kseniia Lysakovskaia
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Jana Schmitzova
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Anna Sawicka
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Ying Chen
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Michael Lidschreiber
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
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18
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Zhang S, Aibara S, Vos SM, Agafonov DE, Lührmann R, Cramer P. Structure of a transcribing RNA polymerase II–U1 snRNP complex. Science 2021; 371:305-309. [DOI: 10.1126/science.abf1870] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 12/07/2020] [Indexed: 12/15/2022]
Affiliation(s)
- Suyang Zhang
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Shintaro Aibara
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Seychelle M. Vos
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Dmitry E. Agafonov
- Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Reinhard Lührmann
- Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
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19
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An emerging role of chromatin-interacting RNA-binding proteins in transcription regulation. Essays Biochem 2020; 64:907-918. [PMID: 33034346 DOI: 10.1042/ebc20200004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 09/08/2020] [Accepted: 09/15/2020] [Indexed: 01/01/2023]
Abstract
Transcription factors (TFs) are well-established key factors orchestrating gene transcription, and RNA-binding proteins (RBPs) are mainly thought to participate in post-transcriptional control of gene. In fact, these two steps are functionally coupled, offering a possibility for reciprocal communications between transcription and regulatory RNAs and RBPs. Recently, a series of exploratory studies, utilizing functional genomic strategies, have revealed that RBPs are prevalently involved in transcription control genome-wide through their interactions with chromatin. Here, we present a refined census of RBPs to grope for such an emerging role and discuss the global view of RBP-chromatin interactions and their functional diversities in transcription regulation.
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20
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Tellier M, Maudlin I, Murphy S. Transcription and splicing: A two-way street. WILEY INTERDISCIPLINARY REVIEWS. RNA 2020; 11:e1593. [PMID: 32128990 DOI: 10.1002/wrna.1593] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 12/18/2019] [Accepted: 02/12/2020] [Indexed: 12/11/2022]
Abstract
RNA synthesis by RNA polymerase II and RNA processing are closely coupled during the transcription cycle of protein-coding genes. This coupling affords opportunities for quality control and regulation of gene expression and the effects can go in both directions. For example, polymerase speed can affect splice site selection and splicing can increase transcription and affect the chromatin landscape. Here we review the many ways that transcription and splicing influence one another, including how splicing "talks back" to transcription. We will also place the connections between transcription and splicing in the context of other RNA processing events that define the exons that will make up the final mRNA. This article is categorized under: RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing.
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Affiliation(s)
- Michael Tellier
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Isabella Maudlin
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Shona Murphy
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
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21
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Linking transcription, RNA polymerase II elongation and alternative splicing. Biochem J 2020; 477:3091-3104. [DOI: 10.1042/bcj20200475] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/31/2020] [Accepted: 08/04/2020] [Indexed: 12/21/2022]
Abstract
Gene expression is an intricately regulated process that is at the basis of cell differentiation, the maintenance of cell identity and the cellular responses to environmental changes. Alternative splicing, the process by which multiple functionally distinct transcripts are generated from a single gene, is one of the main mechanisms that contribute to expand the coding capacity of genomes and help explain the level of complexity achieved by higher organisms. Eukaryotic transcription is subject to multiple layers of regulation both intrinsic — such as promoter structure — and dynamic, allowing the cell to respond to internal and external signals. Similarly, alternative splicing choices are affected by all of these aspects, mainly through the regulation of transcription elongation, making it a regulatory knob on a par with the regulation of gene expression levels. This review aims to recapitulate some of the history and stepping-stones that led to the paradigms held today about transcription and splicing regulation, with major focus on transcription elongation and its effect on alternative splicing.
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22
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Liu Y, Shi SL. The roles of hnRNP A2/B1 in RNA biology and disease. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1612. [PMID: 32588964 DOI: 10.1002/wrna.1612] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/25/2020] [Accepted: 05/26/2020] [Indexed: 12/12/2022]
Abstract
The RNA-binding protein hnRNPA2/B1 is a member of the hnRNPs family and is widely expressed in various tissues. hnRNPA2/B1 recognizes and binds specific RNA substrates and DNA motifs and is involved in the transcription, splicing processing, transport, stability, and translation regulation of a variety of RNA molecules and in regulating the expression of a large number of genes. hnRNPA2/B1 is also involved in telomere maintenance and DNA repair, while its expression changes and mutations are involved in the development of various tumors and neurodegenerative and autoimmune diseases. This paper reviews the role and mechanism of hnRNPA2/B1 in RNA metabolism, tumors, and neurodegenerative and autoimmune diseases. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Yu Liu
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China.,School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Song-Lin Shi
- Cancer Research Center, School of Medicine, Xiamen University, Xiamen, China
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23
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Lee D, Zhang J, Liu J, Gerstein M. Epigenome-based splicing prediction using a recurrent neural network. PLoS Comput Biol 2020; 16:e1008006. [PMID: 32584815 PMCID: PMC7343189 DOI: 10.1371/journal.pcbi.1008006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/08/2020] [Accepted: 06/01/2020] [Indexed: 12/16/2022] Open
Abstract
Alternative RNA splicing provides an important means to expand metazoan transcriptome diversity. Contrary to what was accepted previously, splicing is now thought to predominantly take place during transcription. Motivated by emerging data showing the physical proximity of the spliceosome to Pol II, we surveyed the effect of epigenetic context on co-transcriptional splicing. In particular, we observed that splicing factors were not necessarily enriched at exon junctions and that most epigenetic signatures had a distinctly asymmetric profile around known splice sites. Given this, we tried to build an interpretable model that mimics the physical layout of splicing regulation where the chromatin context progressively changes as the Pol II moves along the guide DNA. We used a recurrent-neural-network architecture to predict the inclusion of a spliced exon based on adjacent epigenetic signals, and we showed that distinct spatio-temporal features of these signals were key determinants of model outcome, in addition to the actual nucleotide sequence of the guide DNA strand. After the model had been trained and tested (with >80% precision-recall curve metric), we explored the derived weights of the latent factors, finding they highlight the importance of the asymmetric time-direction of chromatin context during transcription.
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Affiliation(s)
- Donghoon Lee
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut, United States of America
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States of America
| | - Jing Zhang
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut, United States of America
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States of America
| | - Jason Liu
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut, United States of America
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States of America
| | - Mark Gerstein
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut, United States of America
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States of America
- Department of Computer Science, Yale University, New Haven, Connecticut, United States of America
- Department of Statistics and Data Science, Yale University, New Haven, Connecticut, United States of America
- * E-mail:
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24
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Rambout X, Cho H, Maquat LE. Transcriptional Coactivator PGC-1α Binding to Newly Synthesized RNA via CBP80: A Nexus for Co- and Posttranscriptional Gene Regulation. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2020; 84:47-54. [PMID: 32295928 DOI: 10.1101/sqb.2019.84.040212] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Mammalian cells have many quality-control mechanisms that regulate protein-coding gene expression to ensure proper transcript synthesis, processing, and translation. Should a step in transcript metabolism fail to fulfill requisite spatial, temporal, or structural criteria, including the proper acquisition of RNA-binding proteins, then that step will halt, fail to proceed to the next step, and ultimately result in transcript degradation. Quality-control mechanisms constitute a continuum of processes that initiate in the nucleus and extend to the cytoplasm. Here, we present published and unpublished data for protein-coding genes whose expression is activated by the transcriptional coactivator PGC-1α. We show that PGC-1α movement from chromatin, to which it is recruited by DNA-binding proteins, to CBP80 at the 5' cap of nascent transcripts begins a series of co- and posttranscriptional quality- and quantity-control steps that, in total, ensure proper gene expression.
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Affiliation(s)
- Xavier Rambout
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, Rochester, New York 14642, USA.,Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
| | - Hana Cho
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, Rochester, New York 14642, USA.,Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
| | - Lynne E Maquat
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, Rochester, New York 14642, USA.,Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
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25
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Botto AEC, Muñoz JC, Giono LE, Nieto-Moreno N, Cuenca C, Kornblihtt AR, Muñoz MJ. Reciprocal regulation between alternative splicing and the DNA damage response. Genet Mol Biol 2020; 43:e20190111. [PMID: 32236390 PMCID: PMC7197977 DOI: 10.1590/1678-4685-gmb-2019-0111] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 12/16/2019] [Indexed: 12/16/2022] Open
Abstract
Splicing, the process that catalyzes intron removal and flanking exon ligation, can occur in different ways (alternative splicing) in immature RNAs transcribed from a single gene. In order to adapt to a particular context, cells modulate not only the quantity but also the quality (alternative isoforms) of their transcriptome. Since 95% of the human coding genome is subjected to alternative splicing regulation, it is expected that many cellular pathways are modulated by alternative splicing, as is the case for the DNA damage response. Moreover, recent evidence demonstrates that upon a genotoxic insult, classical DNA damage response kinases such as ATM, ATR and DNA-PK orchestrate the gene expression response therefore modulating alternative splicing which, in a reciprocal way, shapes the response to a damaging agent.
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Affiliation(s)
- Adrian E Cambindo Botto
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiologia, Biologia Molecular y Celular, Instituto de Fisiologia, Biologia Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina
| | - Juan C Muñoz
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiologia, Biologia Molecular y Celular, Instituto de Fisiologia, Biologia Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina
| | - Luciana E Giono
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiologia, Biologia Molecular y Celular, Instituto de Fisiologia, Biologia Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina
| | - Nicolás Nieto-Moreno
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiologia, Biologia Molecular y Celular, Instituto de Fisiologia, Biologia Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina
| | - Carmen Cuenca
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiologia, Biologia Molecular y Celular, Instituto de Fisiologia, Biologia Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina
| | - Alberto R Kornblihtt
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiologia, Biologia Molecular y Celular, Instituto de Fisiologia, Biologia Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina
| | - Manuel J Muñoz
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiologia, Biologia Molecular y Celular, Instituto de Fisiologia, Biologia Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Buenos Aires, Argentina.,Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Milan, Italy.,Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
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26
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Li X, Wang X, Cheng Z, Zhu Q. AGO2 and its partners: a silencing complex, a chromatin modulator, and new features. Crit Rev Biochem Mol Biol 2020; 55:33-53. [DOI: 10.1080/10409238.2020.1738331] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Xiaojing Li
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, Hunan, China
| | - Xueying Wang
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, Hunan, China
| | - Zeneng Cheng
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, Hunan, China
| | - Qubo Zhu
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, Hunan, China
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27
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Kilchert C, Sträßer K, Kunetsky V, Änkö ML. From parts lists to functional significance-RNA-protein interactions in gene regulation. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 11:e1582. [PMID: 31883228 DOI: 10.1002/wrna.1582] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 12/03/2019] [Accepted: 12/07/2019] [Indexed: 12/17/2022]
Abstract
Hundreds of canonical RNA binding proteins facilitate diverse and essential RNA processing steps in cells forming a central regulatory point in gene expression. However, recent discoveries including the identification of a large number of noncanonical proteins bound to RNA have changed our view on RNA-protein interactions merely as necessary steps in RNA biogenesis. As the list of proteins interacting with RNA has expanded, so has the scope of regulation through RNA-protein interactions. In addition to facilitating RNA metabolism, RNA binding proteins help to form subcellular structures and membraneless organelles, and provide means to recruit components of macromolecular complexes to their sites of action. Moreover, RNA-protein interactions are not static in cells but the ribonucleoprotein (RNP) complexes are highly dynamic in response to cellular cues. The identification of novel proteins in complex with RNA and ways cells use these interactions to control cellular functions continues to broaden the scope of RNA regulation in cells and the current challenge is to move from cataloguing the components of RNPs into assigning them functions. This will not only facilitate our understanding of cellular homeostasis but may bring in key insights into human disease conditions where RNP components play a central role. This review brings together the classical view of regulation accomplished through RNA-protein interactions with the novel insights gained from the identification of RNA binding interactomes. We discuss the challenges in combining molecular mechanism with cellular functions on the journey towards a comprehensive understanding of the regulatory functions of RNA-protein interactions in cells. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications aRNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition.
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Affiliation(s)
- Cornelia Kilchert
- Institute of Biochemistry, Justus-Liebig University Giessen, Giessen, Germany
| | - Katja Sträßer
- Institute of Biochemistry, Justus-Liebig University Giessen, Giessen, Germany
| | - Vladislav Kunetsky
- Institute of Biochemistry, Justus-Liebig University Giessen, Giessen, Germany
| | - Minna-Liisa Änkö
- Centre for Reproductive Health and Centre for Cancer Research, Hudson Institute of Medical Research, Melbourne, Victoria, Australia.,Department of Molecular and Translational Science, School of Clinical Sciences, Monash University, Melbourne, Victoria, Australia
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28
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Wissink EM, Vihervaara A, Tippens ND, Lis JT. Nascent RNA analyses: tracking transcription and its regulation. Nat Rev Genet 2019; 20:705-723. [PMID: 31399713 PMCID: PMC6858503 DOI: 10.1038/s41576-019-0159-6] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/04/2019] [Indexed: 12/19/2022]
Abstract
The programmes that direct an organism's development and maintenance are encoded in its genome. Decoding of this information begins with regulated transcription of genomic DNA into RNA. Although transcription and its control can be tracked indirectly by measuring stable RNAs, it is only by directly measuring nascent RNAs that the immediate regulatory changes in response to developmental, environmental, disease and metabolic signals are revealed. Multiple complementary methods have been developed to quantitatively track nascent transcription genome-wide at nucleotide resolution, all of which have contributed novel insights into the mechanisms of gene regulation and transcription-coupled RNA processing. Here we critically evaluate the array of strategies used for investigating nascent transcription and discuss the recent conceptual advances they have provided.
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Affiliation(s)
- Erin M Wissink
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Anniina Vihervaara
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Nathaniel D Tippens
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Tri-Institutional Training Program in Computational Biology and Medicine, New York, NY, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.
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29
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Rahhal R, Seto E. Emerging roles of histone modifications and HDACs in RNA splicing. Nucleic Acids Res 2019; 47:4911-4926. [PMID: 31162605 PMCID: PMC6547430 DOI: 10.1093/nar/gkz292] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 04/09/2019] [Accepted: 04/11/2019] [Indexed: 12/13/2022] Open
Abstract
Histone modifications and RNA splicing, two seemingly unrelated gene regulatory processes, greatly increase proteome diversity and profoundly influence normal as well as pathological eukaryotic cellular functions. Like many histone modifying enzymes, histone deacetylases (HDACs) play critical roles in governing cellular behaviors and are indispensable in numerous biological processes. While the association between RNA splicing and histone modifications is beginning to be recognized, a lack of knowledge exists regarding the role of HDACs in splicing. Recent studies however, reveal that HDACs interact with spliceosomal and ribonucleoprotein complexes, actively control the acetylation states of splicing-associated histone marks and splicing factors, and thereby unexpectedly could modulate splicing. Here, we review the role of histone/protein modifications and HDACs in RNA splicing and discuss the convergence of two parallel fields, which supports the argument that HDACs, and perhaps most histone modifying enzymes, are much more versatile and far more complicated than their initially proposed functions. Analogously, an HDAC-RNA splicing connection suggests that splicing is regulated by additional upstream factors and pathways yet to be defined or not fully characterized. Some human diseases share common underlying causes of aberrant HDACs and dysregulated RNA splicing and, thus, further support the potential link between HDACs and RNA splicing.
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Affiliation(s)
- Raneen Rahhal
- George Washington Cancer Center, Department of Biochemistry & Molecular Medicine, George Washington University School of Medicine & Health Sciences, Washington, DC 20037, USA
| | - Edward Seto
- George Washington Cancer Center, Department of Biochemistry & Molecular Medicine, George Washington University School of Medicine & Health Sciences, Washington, DC 20037, USA
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Baumgartner M, Drake K, Kanadia RN. An Integrated Model of Minor Intron Emergence and Conservation. Front Genet 2019; 10:1113. [PMID: 31798628 PMCID: PMC6865273 DOI: 10.3389/fgene.2019.01113] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 10/16/2019] [Indexed: 12/12/2022] Open
Abstract
Minor introns constitute <0.5% of the introns in the human genome and have remained an enigma since their discovery. These introns are removed by a distinct splicing complex, the minor spliceosome. Both are ancient, tracing back to the last eukaryotic common ancestor (LECA), which is reflected by minor intron enrichment in specific gene families, such as the mitogen activated-protein kinase kinases, voltage-gated sodium and calcium ion channels, and E2F transcription factors. Most minor introns occur as single introns in genes with predominantly major introns. Due to this organization, minor intron-containing gene (MIG) expression requires the coordinated action of two spliceosomes, which increases the probability of missplicing. Thus, one would expect loss of minor introns via purifying selection. This has resulted in complete minor intron loss in at least nine eukaryotic lineages. However, minor introns are highly conserved in land plants and metazoans, where their importance is underscored by embryonic lethality when the minor spliceosome is inactivated. Conditional inactivation of the minor spliceosome has shown that rapidly dividing progenitor cells are highly sensitive to minor spliceosome loss. Indeed, we found that MIGs were significantly enriched in a screen for genes essential for survival in 341 cycling cell lines. Here, we propose that minor introns inserted randomly into genes in LECA or earlier and were subsequently conserved in genes crucial for cycling cell survival. We hypothesize that the essentiality of MIGs allowed minor introns to endure through the unicellularity of early eukaryotic evolution. Moreover, we identified 59 MIGs that emerged after LECA, and that many of these are essential for cycling cell survival, reinforcing our essentiality model for MIG conservation. This suggests that minor intron emergence is dynamic across eukaryotic evolution, and that minor introns should not be viewed as molecular fossils. We also posit that minor intron splicing was co-opted in multicellular evolution as a regulatory switch for en masse control of MIG expression and the biological processes they regulate. Specifically, this mode of regulation could control cell proliferation and thus body size, an idea supported by domestication syndrome, wherein MIGs are enriched in common candidate animal domestication genes.
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Affiliation(s)
- Marybeth Baumgartner
- Department of Physiology and Neurobiology, University of Connecticut, Mansfield, CT, United States.,Institute of Brain and Cognitive Sciences, University of Connecticut, Mansfield, CT, United States
| | - Kyle Drake
- Department of Physiology and Neurobiology, University of Connecticut, Mansfield, CT, United States
| | - Rahul N Kanadia
- Department of Physiology and Neurobiology, University of Connecticut, Mansfield, CT, United States.,Institute of Systems Genomics, University of Connecticut, Mansfield, CT, United States
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31
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Jabre I, Reddy ASN, Kalyna M, Chaudhary S, Khokhar W, Byrne LJ, Wilson CM, Syed NH. Does co-transcriptional regulation of alternative splicing mediate plant stress responses? Nucleic Acids Res 2019; 47:2716-2726. [PMID: 30793202 PMCID: PMC6451118 DOI: 10.1093/nar/gkz121] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/11/2019] [Accepted: 02/13/2019] [Indexed: 12/15/2022] Open
Abstract
Plants display exquisite control over gene expression to elicit appropriate responses under normal and stress conditions. Alternative splicing (AS) of pre-mRNAs, a process that generates two or more transcripts from multi-exon genes, adds another layer of regulation to fine-tune condition-specific gene expression in animals and plants. However, exactly how plants control splice isoform ratios and the timing of this regulation in response to environmental signals remains elusive. In mammals, recent evidence indicate that epigenetic and epitranscriptome changes, such as DNA methylation, chromatin modifications and RNA methylation, regulate RNA polymerase II processivity, co-transcriptional splicing, and stability and translation efficiency of splice isoforms. In plants, the role of epigenetic modifications in regulating transcription rate and mRNA abundance under stress is beginning to emerge. However, the mechanisms by which epigenetic and epitranscriptomic modifications regulate AS and translation efficiency require further research. Dynamic changes in the chromatin landscape in response to stress may provide a scaffold around which gene expression, AS and translation are orchestrated. Finally, we discuss CRISPR/Cas-based strategies for engineering chromatin architecture to manipulate AS patterns (or splice isoforms levels) to obtain insight into the epigenetic regulation of AS.
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Affiliation(s)
- Ibtissam Jabre
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
| | - Anireddy S N Reddy
- Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1878, USA
| | - Maria Kalyna
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences - BOKU, Muthgasse 18, 1190 Vienna, Austria
| | - Saurabh Chaudhary
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
| | - Waqas Khokhar
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
| | - Lee J Byrne
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
| | - Cornelia M Wilson
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
| | - Naeem H Syed
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
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32
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Maudlin IE, Beggs JD. Spt5 modulates cotranscriptional spliceosome assembly in Saccharomyces cerevisiae. RNA (NEW YORK, N.Y.) 2019; 25:1298-1310. [PMID: 31289129 PMCID: PMC6800482 DOI: 10.1261/rna.070425.119] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/29/2019] [Indexed: 06/09/2023]
Abstract
There is increasing evidence from yeast to humans that pre-mRNA splicing occurs mainly cotranscriptionally, such that splicing and transcription are functionally coupled. Currently, there is little insight into the contribution of the core transcription elongation machinery to cotranscriptional spliceosome assembly and pre-mRNA splicing. Spt5 is a member of the core transcription elongation machinery and an essential protein, whose absence in budding yeast causes defects in pre-mRNA splicing. To determine how Spt5 affects pre-mRNA splicing, we used the auxin-inducible degron system to conditionally deplete Spt5 in Saccharomyces cerevisiae and assayed effects on cotranscriptional spliceosome assembly and splicing. We show that Spt5 is needed for efficient splicing and for the accumulation of U5 snRNPs at intron-containing genes, and therefore for stable cotranscriptional assembly of spliceosomes. The defect in cotranscriptional spliceosome assembly can explain the relatively mild splicing defect as being a consequence of the failure of cotranscriptional splicing. Coimmunoprecipitation of Spt5 with core spliceosomal proteins and all spliceosomal snRNAs suggests a model whereby Spt5 promotes cotranscriptional pre-mRNA splicing by stabilizing the association of U5 snRNP with spliceosome complexes as they assemble on the nascent transcript. If this phenomenon is conserved in higher eukaryotes, it has the potential to be important for cotranscriptional regulation of alternative splicing.
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Affiliation(s)
- Isabella E Maudlin
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Jean D Beggs
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
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33
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Neugebauer KM. Nascent RNA and the Coordination of Splicing with Transcription. Cold Spring Harb Perspect Biol 2019; 11:11/8/a032227. [PMID: 31371351 DOI: 10.1101/cshperspect.a032227] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
At each active protein-encoding gene, nascent RNA is tethered to the DNA axis by elongating RNA polymerase II (Pol II) and is continuously altered by splicing and other processing events during its synthesis. This review discusses the development of three major methods that enable us to track the conversion of precursor messenger RNA (pre-mRNA) to messenger RNA (mRNA) products in vivo: live-cell imaging, metabolic labeling of RNA, and RNA-seq of purified nascent RNA. These approaches are complementary, addressing distinct issues of transcription rates and intron lifetimes alongside spatial information regarding the gene position of Pol II at which spliceosomes act. The findings will be placed in the context of active transcription units, each of which-because of the presence of nascent RNA, Pol II, and features of the chromatin environment-will recruit a potentially gene-specific constellation of RNA binding proteins and processing machineries.
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Affiliation(s)
- Karla M Neugebauer
- Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520
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34
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Crane MM, Sands B, Battaglia C, Johnson B, Yun S, Kaeberlein M, Brent R, Mendenhall A. In vivo measurements reveal a single 5'-intron is sufficient to increase protein expression level in Caenorhabditis elegans. Sci Rep 2019; 9:9192. [PMID: 31235724 PMCID: PMC6591249 DOI: 10.1038/s41598-019-45517-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 06/06/2019] [Indexed: 11/29/2022] Open
Abstract
Introns can increase gene expression levels using a variety of mechanisms collectively referred to as Intron Mediated Enhancement (IME). IME has been measured in cell culture and plant models by quantifying expression of intronless and intron-bearing reporter genes in vitro. We developed hardware and software to implement microfluidic chip-based gene expression quantification in vivo. We altered position, number and sequence of introns in reporter genes controlled by the hsp-90 promoter. Consistent with plant and mammalian studies, we determined a single, natural or synthetic, 5'-intron is sufficient for the full IME effect conferred by three synthetic introns, while a 3'-intron is not. We found coding sequence can affect IME; the same three synthetic introns that increase mcherry protein concentration by approximately 50%, increase mEGFP by 80%. We determined IME effect size is not greatly affected by the stronger vit-2 promoter. Our microfluidic imaging approach should facilitate screens for factors affecting IME and other intron-dependent processes.
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Affiliation(s)
- Matthew M Crane
- University of Washington, School of Medicine, Department of Pathology, Seattle, WA, USA
| | - Bryan Sands
- University of Washington, School of Medicine, Department of Pathology, Seattle, WA, USA
| | - Christian Battaglia
- University of Washington, School of Medicine, Department of Pathology, Seattle, WA, USA
| | - Brock Johnson
- University of Washington, School of Medicine, Department of Pathology, Seattle, WA, USA
| | - Soo Yun
- University of Washington, School of Medicine, Department of Pathology, Seattle, WA, USA
| | - Matt Kaeberlein
- University of Washington, School of Medicine, Department of Pathology, Seattle, WA, USA
| | - Roger Brent
- Fred Hutchinson Cancer Research Center, Division of Basic Science, Seattle, WA, USA
| | - Alex Mendenhall
- University of Washington, School of Medicine, Department of Pathology, Seattle, WA, USA.
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35
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Gao X, Fu Y, Ajayi OE, Guo D, Zhang L, Wu Q. Identification of genes underlying phenotypic plasticity of wing size via insulin signaling pathway by network-based analysis in Sogatella furcifera. BMC Genomics 2019; 20:396. [PMID: 31113376 PMCID: PMC6528338 DOI: 10.1186/s12864-019-5793-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 05/10/2019] [Indexed: 12/14/2022] Open
Abstract
Background Phenotypic plasticity is a common and highly adaptive phenomenon where the same genotype produces different phenotypes in response to environmental cues. Sogatella furcifera, a migratory pest of rice exhibits wing dimorphism, is a model insect for studying phenotypic plasticity of wing size. The Insullin-PI3K-Akt-FOXO signaling pathway plays a crucial role in the manipulation of wing size in the migratory insects. However, the regulatory mechanism via the pathway involved in wing dimorphism are still unexplored. Results Accompanied by special alternative splicing, genes involved in muscle contraction and energy metabolism were highly expressed in the wing hinges of macropters, demonstrating their adaptation for energy-demanding long-distance flights. Based on FOXO ChIP-Seq analysis, a total of 1259 putative target genes were observed in the wing hinges, including wing morph development, flight muscle and energy metabolism genes. An integrated gene interaction network was built by combining four heterogeneous datasets, and the IIS-PI3K-Akt-FOXO pathway was clustered in a divided functional module. In total, 45 genes in the module directly interacting with the IIS-PI3K-Akt-FOXO pathway showed differential expression levels between the two wing hinges, thus are regarded as potential Insulin pathway mediated wing dimorphism related genes (IWDRGs). Of the 45 IWDRGs, 5 were selected for verification by gene knockdown experiments, and played significant roles in the insect wing size regulation. Conclusions We provided valuable insights on the genetic basis of wing dimorphism, and also demonstrated that network analysis is a powerful approach to identify new genes regulating wing dimorphic development via insulin signaling pathway in the migratory insect. Electronic supplementary material The online version of this article (10.1186/s12864-019-5793-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xinlei Gao
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Yating Fu
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Olugbenga Emmanuel Ajayi
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Dongyang Guo
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Liqin Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China
| | - Qingfa Wu
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China. .,CAS Key Laboratory of Innate Immunity and Chronic Disease, University of Science and Technology of China, Hefei, 230027, China.
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36
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Light Regulates Plant Alternative Splicing through the Control of Transcriptional Elongation. Mol Cell 2019; 73:1066-1074.e3. [DOI: 10.1016/j.molcel.2018.12.005] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 10/19/2018] [Accepted: 12/07/2018] [Indexed: 01/25/2023]
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37
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Martinez-Macias MI, Moore DA, Green RL, Gomez-Herreros F, Naumann M, Hermann A, Van Damme P, Hafezparast M, Caldecott KW. FUS (fused in sarcoma) is a component of the cellular response to topoisomerase I-induced DNA breakage and transcriptional stress. Life Sci Alliance 2019; 2:2/2/e201800222. [PMID: 30808650 PMCID: PMC6391683 DOI: 10.26508/lsa.201800222] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 02/13/2019] [Accepted: 02/15/2019] [Indexed: 12/11/2022] Open
Abstract
This work shows that the ALS-associated protein FUS is a component of the cellular response to transcriptional stress induced by topoisomerase I–induced DNA breakage, thereby accumulating at sites of nucleolar rRNA synthesis. FUS (fused in sarcoma) plays a key role in several steps of RNA metabolism, and dominant mutations in this protein are associated with neurodegenerative diseases. Here, we show that FUS is a component of the cellular response to topoisomerase I (TOP1)–induced DNA breakage; relocalising to the nucleolus in response to RNA polymerase II (Pol II) stalling at sites of TOP1-induced DNA breaks. This relocalisation is rapid and dynamic, reversing following the removal of TOP1-induced breaks and coinciding with the recovery of global transcription. Importantly, FUS relocalisation following TOP1-induced DNA breakage is associated with increased FUS binding at sites of RNA polymerase I transcription in ribosomal DNA and reduced FUS binding at sites of RNA Pol II transcription, suggesting that FUS relocates from sites of stalled RNA Pol II either to regulate pre-mRNA processing during transcriptional stress or to modulate ribosomal RNA biogenesis. Importantly, FUS-mutant patient fibroblasts are hypersensitive to TOP1-induced DNA breakage, highlighting the possible relevance of these findings to neurodegeneration.
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Affiliation(s)
| | - Duncan Aq Moore
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, England
| | - Ryan L Green
- Neuroscience, School of Life Sciences, University of Sussex, Falmer, Brighton, England
| | - Fernando Gomez-Herreros
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, England.,Instituto de Biomedicina de Sevilla, Hospital Virgen del Rocio-Centro Superior de Investigaciones Cientificas-Universidad de Sevilla, Seville, Spain
| | - Marcel Naumann
- Department of Neurology, Technische Universität Dresden, and German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany.,Translational Neurodegeneration Section "Albrecht-Kossel", Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Andreas Hermann
- Department of Neurology, Technische Universität Dresden, and German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany.,Center for Transdisciplinary Neurosciences Rostock, University Medical Center Rostock, University of Rostock, Rostock, Germany.,Translational Neurodegeneration Section "Albrecht-Kossel", Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | | | - Majid Hafezparast
- Neuroscience, School of Life Sciences, University of Sussex, Falmer, Brighton, England
| | - Keith W Caldecott
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, England
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Chaudhary S, Khokhar W, Jabre I, Reddy ASN, Byrne LJ, Wilson CM, Syed NH. Alternative Splicing and Protein Diversity: Plants Versus Animals. FRONTIERS IN PLANT SCIENCE 2019; 10:708. [PMID: 31244866 PMCID: PMC6581706 DOI: 10.3389/fpls.2019.00708] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 05/13/2019] [Indexed: 05/11/2023]
Abstract
Plants, unlike animals, exhibit a very high degree of plasticity in their growth and development and employ diverse strategies to cope with the variations during diurnal cycles and stressful conditions. Plants and animals, despite their remarkable morphological and physiological differences, share many basic cellular processes and regulatory mechanisms. Alternative splicing (AS) is one such gene regulatory mechanism that modulates gene expression in multiple ways. It is now well established that AS is prevalent in all multicellular eukaryotes including plants and humans. Emerging evidence indicates that in plants, as in animals, transcription and splicing are coupled. Here, we reviewed recent evidence in support of co-transcriptional splicing in plants and highlighted similarities and differences between plants and humans. An unsettled question in the field of AS is the extent to which splice isoforms contribute to protein diversity. To take a critical look at this question, we presented a comprehensive summary of the current status of research in this area in both plants and humans, discussed limitations with the currently used approaches and suggested improvements to current methods and alternative approaches. We end with a discussion on the potential role of epigenetic modifications and chromatin state in splicing memory in plants primed with stresses.
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Affiliation(s)
- Saurabh Chaudhary
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
| | - Waqas Khokhar
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
| | - Ibtissam Jabre
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
| | - Anireddy S. N. Reddy
- Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, United States
| | - Lee J. Byrne
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
| | - Cornelia M. Wilson
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
| | - Naeem H. Syed
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
- *Correspondence: Naeem H. Syed,
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Smurova K, De Wulf P. Centromere and Pericentromere Transcription: Roles and Regulation … in Sickness and in Health. Front Genet 2018; 9:674. [PMID: 30627137 PMCID: PMC6309819 DOI: 10.3389/fgene.2018.00674] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/04/2018] [Indexed: 12/26/2022] Open
Abstract
The chromosomal loci known as centromeres (CEN) mediate the equal distribution of the duplicated genome between both daughter cells. Specifically, centromeres recruit a protein complex named the kinetochore, that bi-orients the replicated chromosome pairs to the mitotic or meiotic spindle structure. The paired chromosomes are then separated, and the individual chromosomes segregate in opposite direction along the regressing spindle into each daughter cell. Erroneous kinetochore assembly or activity produces aneuploid cells that contain an abnormal number of chromosomes. Aneuploidy may incite cell death, developmental defects (including genetic syndromes), and cancer (>90% of all cancer cells are aneuploid). While kinetochores and their activities have been preserved through evolution, the CEN DNA sequences have not. Hence, to be recognized as sites for kinetochore assembly, CEN display conserved structural themes. In addition, CEN nucleosomes enclose a CEN-exclusive variant of histone H3, named CENP-A, and carry distinct epigenetic labels on CENP-A and the other CEN histone proteins. Through the cell cycle, CEN are transcribed into non-coding RNAs. After subsequent processing, they become key components of the CEN chromatin by marking the CEN locus and by stably anchoring the CEN-binding kinetochore proteins. CEN transcription is tightly regulated, of low intensity, and essential for differentiation and development. Under- or overexpression of CEN transcripts, as documented for myriad cancers, provoke chromosome missegregation and aneuploidy. CEN are genetically stable and fully competent only when they are insulated from the surrounding, pericentromeric chromatin, which must be silenced. We will review CEN transcription and its contribution to faithful kinetochore function. We will further discuss how pericentromeric chromatin is silenced by RNA processing and transcriptionally repressive chromatin marks. We will report on the transcriptional misregulation of (peri)centromeres during stress, natural aging, and disease and reflect on whether their transcripts can serve as future diagnostic tools and anti-cancer targets in the clinic.
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Affiliation(s)
- Ksenia Smurova
- Centre for Integrative Biology, University of Trento, Trento, Italy
| | - Peter De Wulf
- Centre for Integrative Biology, University of Trento, Trento, Italy
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The Development and Use of Scalable Systems for Studying Aberrant Splicing in SF3B1-Mutant CLL. Methods Mol Biol 2018. [PMID: 30350199 DOI: 10.1007/978-1-4939-8876-1_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Mutational landscape of CLL is now known to include recurrent non-synonymous mutations in SF3B1, a core splicing factor. About 5-10% of newly diagnosed CLL harbor these mutations which are typically limited to HEAT domains in the carboxyl-terminus of the protein. Importantly, the mutations are not specific to CLL but also present in several unrelated clonal disorders. Analysis of patient samples and cell lines has shown the primary splicing aberration in SF3B1-mutant cells to the use of novel or "cryptic" 3' splice sites (3SS). Advances in genome-editing and next-generation sequencing (NGS) have allowed development of isogenic models and detailed analysis of changes to the transcriptome with relative ease. In this manuscript, we focus on two relevant methods to study splicing factor mutations in CLL: development of isogenic scalable cell lines and informatics analysis of RNA-Seq datasets.
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Cui X, Han W, Li J, Feng R, Zhou Z, Han J, Li M, Wang S, Zhang W, Lei Q, Zhang J, Liu Y, Hu Y. Heat shock factor 4 regulates the expression of HSP25 and alpha B-crystallin by associating with DEXD/H-box RNA helicase UAP56. Cell Stress Chaperones 2018; 23:571-579. [PMID: 29164525 PMCID: PMC6045540 DOI: 10.1007/s12192-017-0865-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 11/08/2017] [Accepted: 11/10/2017] [Indexed: 11/24/2022] Open
Abstract
Heat shock factor 4 controls the transcription of small heat shock proteins (e.g., HSP25, alpha B-cyrstallin, and r-crystallin), that play important roles in modulating lens proteostasis. However, the molecular mechanism underlying HSF4-mediated transcription is still unclear. Using yeast two hybrid, we found that HSF4 interacts with the ATP-dependent DEXD/H-box RNA helicase UAP56, and their interaction in lens epithelial cell line was further confirmed by GST-pull down assay. UAP56 is a vital regulator of pre-mRNA splicing and mature mRNA nuclear export. The immunofluorescence assay showed that HSF4 and UBA56 co-localize with each other in the nucleus of lens epithelial cells. Ectopic UAP56 upregulated HSF4-controlled HSP25 and alpha B-crystallin proteins expression, while knocking down UAP56 by shRNA reversed it. Moreover, UAP56 interacts with and facilitates the nuclear exportation of HSP25 and alpha B-crystallin mRNA without impacting their total mRNA expression level. In lens tissues, both UAP56 and HSF4 are expressed in the same nucleus of lens fiber cells, and their expression levels are simultaneously reduced with fiber cell maturation. Taken together, these data suggested that UAP56 is a novel regulator of HSF4 and might upregulate HSF4's downstream mRNA maturation and nuclear exportation.
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Affiliation(s)
- Xiukun Cui
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - Wenxiu Han
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - Jing Li
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - Riping Feng
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - Zheng Zhou
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - JiuLi Han
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - Mengyuan Li
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - Shuangfeng Wang
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - Wanting Zhang
- Kaifeng Key Laboratory of Cataract and Myopia, Institute of Eye disease, Kaifeng Central Hospital, Kaifeng, China
| | - Qin Lei
- Kaifeng Key Laboratory of Cataract and Myopia, Institute of Eye disease, Kaifeng Central Hospital, Kaifeng, China
| | - Jun Zhang
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China
| | - Yutiao Liu
- Department of Cell biology and Anatomy, Augusta University, Augusta, GA, USA
| | - Yanzhong Hu
- National Joint Laboratory For Antibody Drug Enginerring, Henan-international Union Laboratory of Antibody Medicine, Department of Cell Biology and Genetics, School of Basic Medical Science, Henan University, Kaifeng, Henan, 475014, China.
- Kaifeng Key Laboratory of Cataract and Myopia, Institute of Eye disease, Kaifeng Central Hospital, Kaifeng, China.
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Madhu Krishna B, Chaudhary S, Mishra DR, Naik SK, Suklabaidya S, Adhya AK, Mishra SK. Estrogen receptor α dependent regulation of estrogen related receptor β and its role in cell cycle in breast cancer. BMC Cancer 2018; 18:607. [PMID: 29843638 PMCID: PMC5975398 DOI: 10.1186/s12885-018-4528-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 05/18/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Breast cancer (BC) is highly heterogeneous with ~ 60-70% of estrogen receptor positive BC patient's response to anti-hormone therapy. Estrogen receptors (ERs) play an important role in breast cancer progression and treatment. Estrogen related receptors (ERRs) are a group of nuclear receptors which belong to orphan nuclear receptors, which have sequence homology with ERs and share target genes. Here, we investigated the possible role and clinicopathological importance of ERRβ in breast cancer. METHODS Estrogen related receptor β (ERRβ) expression was examined using tissue microarray slides (TMA) of Breast Carcinoma patients with adjacent normal by immunohistochemistry and in breast cancer cell lines. In order to investigate whether ERRβ is a direct target of ERα, we investigated the expression of ERRβ in short hairpin ribonucleic acid knockdown of ERα breast cancer cells by western blot, qRT-PCR and RT-PCR. We further confirmed the binding of ERα by electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), Re-ChIP and luciferase assays. Fluorescence-activated cell sorting analysis (FACS) was performed to elucidate the role of ERRβ in cell cycle regulation. A Kaplan-Meier Survival analysis of GEO dataset was performed to correlate the expression of ERRβ with survival in breast cancer patients. RESULTS Tissue microarray (TMA) analysis showed that ERRβ is significantly down-regulated in breast carcinoma tissue samples compared to adjacent normal. ER + ve breast tumors and cell lines showed a significant expression of ERRβ compared to ER-ve tumors and cell lines. Estrogen treatment significantly induced the expression of ERRβ and it was ERα dependent. Mechanistic analyses indicate that ERα directly targets ERRβ through estrogen response element and ERRβ also mediates cell cycle regulation through p18, p21cip and cyclin D1 in breast cancer cells. Our results also showed the up-regulation of ERRβ promoter activity in ectopically co-expressed ERα and ERRβ breast cancer cell lines. Fluorescence-activated cell sorting analysis (FACS) showed increased G0/G1 phase cell population in ERRβ overexpressed MCF7 cells. Furthermore, ERRβ expression was inversely correlated with overall survival in breast cancer. Collectively our results suggest cell cycle and tumor suppressor role of ERRβ in breast cancer cells which provide a potential avenue to target ERRβ signaling pathway in breast cancer. CONCLUSION Our results indicate that ERRβ is a negative regulator of cell cycle and a possible tumor suppressor in breast cancer. ERRβ could be therapeutic target for the treatment of breast cancer.
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Affiliation(s)
- B Madhu Krishna
- Cancer Biology Lab, Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India
| | - Sanjib Chaudhary
- Cancer Biology Lab, Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India.,Present address: Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center (UNMC), Omaha, NE, USA
| | - Dipti Ranjan Mishra
- Department of Gene Function & Regulation, Institute of Life Sciences, Nalco square, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India
| | - Sanoj K Naik
- Cancer Biology Lab, Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India
| | - S Suklabaidya
- Tumor Microenvironment and Animal Models Lab, Department of Translational Research and Technology Development, Institute of Life Sciences, Nalco square, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India
| | - A K Adhya
- Department of Pathology, Kalinga Institute of Medical Sciences, Chandaka Industrial Estate, KIIT Rd, Patia, Bhubaneswar, Odisha, India
| | - Sandip K Mishra
- Cancer Biology Lab, Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar, Odisha, 751023, India.
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Schaub A, Glasmacher E. Splicing in immune cells-mechanistic insights and emerging topics. Int Immunol 2018; 29:173-181. [PMID: 28498981 PMCID: PMC5890895 DOI: 10.1093/intimm/dxx026] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 04/27/2017] [Indexed: 11/26/2022] Open
Abstract
Differential splicing of mRNAs not only enables regulation of gene expression levels, but also ensures a high degree of gene-product diversity. The extent to which splicing of mRNAs is utilized as a mechanism in immune cells has become evident within the last few years. Still, only a few of these mechanisms have been well studied. In this review, we discuss some of the best-understood mechanisms, for instance the differential splicing of CD45 in T cells, as well as immunoglobulin genes in B cells. Beyond that we provide general mechanistic insights on how, when and where this process takes place and discuss the current knowledge regarding these topics in immune cells. We also highlight some of the reported links to immune-related diseases, genome-wide sequencing studies that revealed thousands of differentially spliced transcripts, as well as splicing studies on immune cells that remain mechanistically not fully understood. We thereby display potential emerging topics for future studies centered on splicing mechanisms in immune cells.
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Affiliation(s)
- Annalisa Schaub
- Institute for Diabetes and Obesity, Helmholtz Zentrum München, German Center for Diabetes Research (DZD), 85764 München-Neuherberg, Germany
| | - Elke Glasmacher
- Institute for Diabetes and Obesity, Helmholtz Zentrum München, German Center for Diabetes Research (DZD), 85764 München-Neuherberg, Germany
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Li T, Liu Q, Garza N, Kornblau S, Jin VX. Integrative analysis reveals functional and regulatory roles of H3K79me2 in mediating alternative splicing. Genome Med 2018; 10:30. [PMID: 29665865 PMCID: PMC5902843 DOI: 10.1186/s13073-018-0538-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 03/29/2018] [Indexed: 01/26/2023] Open
Abstract
Background Accumulating evidence suggests alternative splicing (AS) is a co-transcriptional splicing process not only controlled by RNA-binding splicing factors, but also mediated by epigenetic regulators, such as chromatin structure, nucleosome density, and histone modification. Aberrant AS plays an important role in regulating various diseases, including cancers. Methods In this study, we integrated AS events derived from RNA-seq with H3K79me2 ChIP-seq data across 34 different normal and cancer cell types and found the higher enrichment of H3K79me2 in two AS types, skipping exon (SE) and alternative 3′ splice site (A3SS). Results Interestingly, by applying self-organizing map (SOM) clustering, we unveiled two clusters mainly comprised of blood cancer cell types with a strong correlation between H3K79me2 and SE. Remarkably, the expression of transcripts associated with SE was not significantly different from that of those not associated with SE, indicating the involvement of H3K79me2 in splicing has little impact on full mRNA transcription. We further showed that the deletion of DOT1L1, the sole H3K79 methyltransferase, impeded leukemia cell proliferation as well as switched exon skipping to the inclusion isoform in two MLL-rearranged acute myeloid leukemia cell lines. Our data demonstrate H3K79me2 was involved in mediating SE processing, which might in turn influence transformation and disease progression in leukemias. Conclusions Collectively, our work for the first time reveals that H3K79me2 plays functional and regulatory roles through a co-transcriptional splicing mechanism. Electronic supplementary material The online version of this article (10.1186/s13073-018-0538-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tianbao Li
- College of Life Science, Jilin University, Changchun, 130012, China.,Department of Molecular Medicine, University of Texas Health, 8403 Floyd Curl, San Antonio, TX, 78229, USA
| | - Qi Liu
- Department of Molecular Medicine, University of Texas Health, 8403 Floyd Curl, San Antonio, TX, 78229, USA
| | - Nick Garza
- Department of Molecular Medicine, University of Texas Health, 8403 Floyd Curl, San Antonio, TX, 78229, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Steven Kornblau
- Department of Leukemia, UT MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Victor X Jin
- Department of Molecular Medicine, University of Texas Health, 8403 Floyd Curl, San Antonio, TX, 78229, USA.
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Michelini F, Jalihal AP, Francia S, Meers C, Neeb ZT, Rossiello F, Gioia U, Aguado J, Jones-Weinert C, Luke B, Biamonti G, Nowacki M, Storici F, Carninci P, Walter NG, d'Adda di Fagagna F. From "Cellular" RNA to "Smart" RNA: Multiple Roles of RNA in Genome Stability and Beyond. Chem Rev 2018; 118:4365-4403. [PMID: 29600857 DOI: 10.1021/acs.chemrev.7b00487] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Coding for proteins has been considered the main function of RNA since the "central dogma" of biology was proposed. The discovery of noncoding transcripts shed light on additional roles of RNA, ranging from the support of polypeptide synthesis, to the assembly of subnuclear structures, to gene expression modulation. Cellular RNA has therefore been recognized as a central player in often unanticipated biological processes, including genomic stability. This ever-expanding list of functions inspired us to think of RNA as a "smart" phone, which has replaced the older obsolete "cellular" phone. In this review, we summarize the last two decades of advances in research on the interface between RNA biology and genome stability. We start with an account of the emergence of noncoding RNA, and then we discuss the involvement of RNA in DNA damage signaling and repair, telomere maintenance, and genomic rearrangements. We continue with the depiction of single-molecule RNA detection techniques, and we conclude by illustrating the possibilities of RNA modulation in hopes of creating or improving new therapies. The widespread biological functions of RNA have made this molecule a reoccurring theme in basic and translational research, warranting it the transcendence from classically studied "cellular" RNA to "smart" RNA.
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Affiliation(s)
- Flavia Michelini
- IFOM - The FIRC Institute of Molecular Oncology , Milan , 20139 , Italy
| | - Ameya P Jalihal
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry , University of Michigan , Ann Arbor , Michigan 48109-1055 , United States
| | - Sofia Francia
- IFOM - The FIRC Institute of Molecular Oncology , Milan , 20139 , Italy.,Istituto di Genetica Molecolare , CNR - Consiglio Nazionale delle Ricerche , Pavia , 27100 , Italy
| | - Chance Meers
- School of Biological Sciences , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Zachary T Neeb
- Institute of Cell Biology , University of Bern , Baltzerstrasse 4 , 3012 Bern , Switzerland
| | | | - Ubaldo Gioia
- IFOM - The FIRC Institute of Molecular Oncology , Milan , 20139 , Italy
| | - Julio Aguado
- IFOM - The FIRC Institute of Molecular Oncology , Milan , 20139 , Italy
| | | | - Brian Luke
- Institute of Developmental Biology and Neurobiology , Johannes Gutenberg University , 55099 Mainz , Germany.,Institute of Molecular Biology (IMB) , 55128 Mainz , Germany
| | - Giuseppe Biamonti
- Istituto di Genetica Molecolare , CNR - Consiglio Nazionale delle Ricerche , Pavia , 27100 , Italy
| | - Mariusz Nowacki
- Institute of Cell Biology , University of Bern , Baltzerstrasse 4 , 3012 Bern , Switzerland
| | - Francesca Storici
- School of Biological Sciences , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Piero Carninci
- RIKEN Center for Life Science Technologies , 1-7-22 Suehiro-cho, Tsurumi-ku , Yokohama City , Kanagawa 230-0045 , Japan
| | - Nils G Walter
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry , University of Michigan , Ann Arbor , Michigan 48109-1055 , United States
| | - Fabrizio d'Adda di Fagagna
- IFOM - The FIRC Institute of Molecular Oncology , Milan , 20139 , Italy.,Istituto di Genetica Molecolare , CNR - Consiglio Nazionale delle Ricerche , Pavia , 27100 , Italy
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ChIP and ChIP-Related Techniques: Expanding the Fields of Application and Improving ChIP Performance. Methods Mol Biol 2018; 1689:1-7. [PMID: 29027160 DOI: 10.1007/978-1-4939-7380-4_1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Protein-DNA interactions in vivo can be detected and quantified by chromatin immunoprecipitation (ChIP). ChIP has been instrumental for the advancement of epigenetics and has set the groundwork for the development of a number of ChIP-related techniques that have provided valuable information about the organization and function of genomes. Here, we provide an introduction to ChIP and discuss the applications of ChIP in different research areas. We also review some of the strategies that have been devised to improve ChIP performance.
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47
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Eberle AB. Spike-In Normalization of ChIP Data Using DNA-DIG-Antibody Complex. Methods Mol Biol 2018; 1689:227-238. [PMID: 29027177 DOI: 10.1007/978-1-4939-7380-4_18] [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] [Indexed: 06/07/2023]
Abstract
Chromatin immunoprecipitation (ChIP) is a widely used method to determine the occupancy of specific proteins within the genome, helping to unravel the function and activity of specific genomic regions. In ChIP experiments, normalization of the obtained data by a suitable internal reference is crucial. However, particularly when comparing differently treated samples, such a reference is difficult to identify. Here, a simple method to improve the accuracy and reliability of ChIP experiments by the help of an external reference is described. An artificial molecule, composed of a well-defined digoxigenin (DIG) labeled DNA fragment in complex with an anti-DIG antibody, is synthesized and added to each chromatin sample before immunoprecipitation. During the ChIP procedure, the DNA-DIG-antibody complex undergoes the same treatments as the chromatin and is therefore purified and quantified together with the chromatin of interest. This external reference compensates for variability during the ChIP routine and improves the similarity between replicates, thereby emphasizing the biological differences between samples.
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Affiliation(s)
- Andrea B Eberle
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
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48
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Abstract
DNA methylation is a dynamic epigenetic mark that characterizes different cellular developmental stages, including tissue-specific profiles. This CpG dinucleotide modification cooperates in the regulation of the output of the cellular genetic content, in both healthy and pathological conditions. According to endogenous and exogenous stimuli, DNA methylation is involved in gene transcription, alternative splicing, imprinting, X-chromosome inactivation, and control of transposable elements. When these dinucleotides are organized in dense regions are called CpG islands (CGIs), being commonly known as transcriptional regulatory regions frequently associated with the promoter region of several genes. In cancer, promoter DNA hypermethylation events sustained the mechanistic hypothesis of epigenetic transcriptional silencing of an increasing number of tumor suppressor genes. CGI hypomethylation-mediated reactivation of oncogenes was also documented in several cancer types. In this chapter, we aim to summarize the functional consequences of the differential DNA methylation at CpG dinucleotides in cancer, focused in CGIs. Interestingly, cancer methylome is being recently explored, looking for biomarkers for diagnosis, prognosis, and predictors of drug response.
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Affiliation(s)
- Humberto J Ferreira
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Catalonia, Spain
| | - Manel Esteller
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Catalonia, Spain.
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Catalonia, Spain.
- Department of Physiological Sciences II, School of Medicine, University of Barcelona, Barcelona, Catalonia, Spain.
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49
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Pozzi B, Bragado L, Will CL, Mammi P, Risso G, Urlaub H, Lührmann R, Srebrow A. SUMO conjugation to spliceosomal proteins is required for efficient pre-mRNA splicing. Nucleic Acids Res 2017; 45:6729-6745. [PMID: 28379520 PMCID: PMC5499870 DOI: 10.1093/nar/gkx213] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 03/24/2017] [Indexed: 12/26/2022] Open
Abstract
Pre-mRNA splicing is catalyzed by the spliceosome, a multi-megadalton ribonucleoprotein machine. Previous work from our laboratory revealed the splicing factor SRSF1 as a regulator of the SUMO pathway, leading us to explore a connection between this pathway and the splicing machinery. We show here that addition of a recombinant SUMO-protease decreases the efficiency of pre-mRNA splicing in vitro. By mass spectrometry analysis of anti-SUMO immunoprecipitated proteins obtained from purified splicing complexes formed along the splicing reaction, we identified spliceosome-associated SUMO substrates. After corroborating SUMOylation of Prp3 in cultured cells, we defined Lys 289 and Lys 559 as bona fide SUMO attachment sites within this spliceosomal protein. We further demonstrated that a Prp3 SUMOylation-deficient mutant while still capable of interacting with U4/U6 snRNP components, is unable to co-precipitate U2 and U5 snRNA and the spliceosomal proteins U2-SF3a120 and U5-Snu114. This SUMOylation-deficient mutant fails to restore the splicing of different pre-mRNAs to the levels achieved by the wild type protein, when transfected into Prp3-depleted cultured cells. This mutant also shows a diminished recruitment to active spliceosomes, compared to the wild type protein. These findings indicate that SUMO conjugation plays a role during the splicing process and suggest the involvement of Prp3 SUMOylation in U4/U6•U5 tri-snRNP formation and/or recruitment.
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Affiliation(s)
- Berta Pozzi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Laureano Bragado
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Cindy L Will
- Department of Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Pablo Mammi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Guillermo Risso
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, MPI for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany.,Bioanalytics Group, Institute for Clinical Chemistry, University Medical Center Göttingen, Robert-Koch-Straße 40, D-37075 Göttingen, Germany
| | - Reinhard Lührmann
- Department of Cellular Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Anabella Srebrow
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular, Buenos Aires, Argentina.,CONICET-Universidad de Buenos Aires, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), Buenos Aires, Argentina
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Karijolich J, Zhao Y, Alla R, Glaunsinger B. Genome-wide mapping of infection-induced SINE RNAs reveals a role in selective mRNA export. Nucleic Acids Res 2017; 45:6194-6208. [PMID: 28334904 PMCID: PMC5449642 DOI: 10.1093/nar/gkx180] [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: 06/16/2016] [Accepted: 03/08/2017] [Indexed: 12/11/2022] Open
Abstract
Short interspersed nuclear elements (SINEs) are retrotransposons evolutionarily derived from endogenous RNA Polymerase III RNAs. Though SINE elements have undergone exaptation into gene regulatory elements, how transcribed SINE RNA impacts transcriptional and post-transcriptional regulation is largely unknown. This is partly due to a lack of information regarding which of the loci have transcriptional potential. Here, we present an approach (short interspersed nuclear element sequencing, SINE-seq), which selectively profiles RNA Polymerase III-derived SINE RNA, thereby identifying transcriptionally active SINE loci. Applying SINE-seq to monitor murine B2 SINE expression during a gammaherpesvirus infection revealed transcription from 28 270 SINE loci, with ∼50% of active SINE elements residing within annotated RNA Polymerase II loci. Furthermore, B2 RNA can form intermolecular RNA–RNA interactions with complementary mRNAs, leading to nuclear retention of the targeted mRNA via a mechanism involving p54nrb. These findings illuminate a pathway for the selective regulation of mRNA export during stress via retrotransposon activation.
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Affiliation(s)
- John Karijolich
- Howard Hughes Medical Institute, University of California, Berkeley, CA 94720-3370, USA.,Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3370, USA.,Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232-2363, USA
| | - Yang Zhao
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232-2363, USA
| | - Ravi Alla
- California Institute for Quantitative Biology, University of California, Berkeley, CA 94720-3370, USA
| | - Britt Glaunsinger
- Howard Hughes Medical Institute, University of California, Berkeley, CA 94720-3370, USA.,Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3370, USA.,California Institute for Quantitative Biology, University of California, Berkeley, CA 94720-3370, USA
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