1
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Hardtke HA, Moreno RY, Zhang YJ. Protocol for the in vitro reconstruction of site-specifically phosphorylated RNA Pol II to identify the recruitment of novel transcription regulators. STAR Protoc 2024; 5:103277. [PMID: 39196783 PMCID: PMC11400965 DOI: 10.1016/j.xpro.2024.103277] [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: 05/17/2024] [Revised: 07/07/2024] [Accepted: 08/06/2024] [Indexed: 08/30/2024] Open
Abstract
The repetitive C-terminal domain (CTD) of the largest subunit of RNA polymerase II (RNAPII) becomes differentially phosphorylated throughout the transcription cycle. Here, we present a protocol to site-specifically phosphorylate the CTD of RNAPII by leveraging the specificity of well-characterized CTD kinases. We describe the steps for optimal phosphorylation of the CTD and the preparation of nuclear protein extract. This protocol can be used to identify the interactome of a phospho-CTD and has the potential to identify novel RNAPII-binding proteins. For complete details on the use and execution of this protocol, please refer to Moreno et al.1.
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Affiliation(s)
- Haley A Hardtke
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA.
| | - Rosamaria Y Moreno
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA
| | - Y Jessie Zhang
- Department of Molecular Biosciences, University of Texas, Austin, TX 78712, USA.
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2
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Zhang Q, Kim W, Panina SB, Mayfield JE, Portz B, Zhang YJ. Variation of C-terminal domain governs RNA polymerase II genomic locations and alternative splicing in eukaryotic transcription. Nat Commun 2024; 15:7985. [PMID: 39266551 PMCID: PMC11393077 DOI: 10.1038/s41467-024-52391-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 09/04/2024] [Indexed: 09/14/2024] Open
Abstract
The C-terminal domain of RPB1 (CTD) orchestrates transcription by recruiting regulators to RNA Pol II upon phosphorylation. With CTD driving condensate formation on gene loci, the molecular mechanism behind how CTD-mediated recruitment of transcriptional regulators influences condensates formation remains unclear. Our study unveils that phosphorylation reversibly dissolves phase separation induced by the unphosphorylated CTD. Phosphorylated CTD, upon specific association with transcription regulators, forms distinct condensates from unphosphorylated CTD. Functional studies demonstrate CTD variants with diverse condensation properties exhibit differences in promoter binding and mRNA co-processing in cells. Notably, varying CTD lengths influence the assembly of RNA processing machinery and alternative splicing outcomes, which in turn affects cellular growth, linking the evolution of CTD variation/length with the complexity of splicing from yeast to human. These findings provide compelling evidence for a model wherein post-translational modification enables the transition of functionally specialized condensates, highlighting a co-evolution link between CTD condensation and splicing.
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Affiliation(s)
- Qian Zhang
- Department of Molecular Biosciences, University of Texas, Austin, TX, USA
| | - Wantae Kim
- McKetta Department of Chemical Engineering, University of Texas, Austin, TX, USA
| | - Svetlana B Panina
- Department of Molecular Biosciences, University of Texas, Austin, TX, USA
| | - Joshua E Mayfield
- Department of Pharmacology, Pathology, Chemistry, and Biochemistry, and Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
| | | | - Y Jessie Zhang
- Department of Molecular Biosciences, University of Texas, Austin, TX, USA.
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3
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Rivosecchi J, Jurikova K, Cusanelli E. Telomere-specific regulation of TERRA and its impact on telomere stability. Semin Cell Dev Biol 2024; 157:3-23. [PMID: 38088000 DOI: 10.1016/j.semcdb.2023.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 11/02/2023] [Indexed: 01/08/2024]
Abstract
TERRA is a class of telomeric repeat-containing RNAs that are expressed from telomeres in multiple organisms. TERRA transcripts play key roles in telomere maintenance and their physiological levels are essential to maintain the integrity of telomeric DNA. Indeed, deregulated TERRA expression or its altered localization can impact telomere stability by multiple mechanisms including fueling transcription-replication conflicts, promoting resection of chromosome ends, altering the telomeric chromatin, and supporting homologous recombination. Therefore, a fine-tuned control of TERRA is important to maintain the integrity of the genome. Several studies have reported that different cell lines express substantially different levels of TERRA. Most importantly, TERRA levels markedly vary among telomeres of a given cell type, indicating the existence of telomere-specific regulatory mechanisms which may help coordinate TERRA functions. TERRA molecules contain distinct subtelomeric sequences, depending on their telomere of origin, which may instruct specific post-transcriptional modifications or mediate distinct functions. In addition, all TERRA transcripts share a repetitive G-rich sequence at their 3' end which can form DNA:RNA hybrids and fold into G-quadruplex structures. Both structures are involved in TERRA functions and can critically affect telomere stability. In this review, we examine the mechanisms controlling TERRA levels and the impact of their telomere-specific regulation on telomere stability. We compare evidence obtained in different model organisms, discussing recent advances as well as controversies in the field. Furthermore, we discuss the importance of DNA:RNA hybrids and G-quadruplex structures in the context of TERRA biology and telomere maintenance.
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Affiliation(s)
- Julieta Rivosecchi
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy
| | - Katarina Jurikova
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy; Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina, 84215 Bratislava, Slovakia
| | - Emilio Cusanelli
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy.
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4
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Barman P, Ferdoush J, Kaja A, Chakraborty P, Uprety B, Bhaumik R, Bhaumik R, Bhaumik SR. Ubiquitin-proteasome system regulation of a key gene regulatory factor, Paf1C. Gene 2024; 894:148004. [PMID: 37977317 DOI: 10.1016/j.gene.2023.148004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 11/08/2023] [Accepted: 11/14/2023] [Indexed: 11/19/2023]
Abstract
Paf1 (Polymerase-associated factor 1) complex (Paf1C) is evolutionarily conserved from yeast to humans, and facilitates transcription elongation as well as co-transcriptional histone covalent modifications and mRNA 3'-end processing. Thus, Paf1C is a key player in regulation of eukaryotic gene expression. Paf1C consists of Paf1, Cdc73, Ctr9, Leo1 and Rtf1 in both yeast and humans, but it has an additional component, Ski8, in humans. The abundances of these components regulate the assembly of Paf1C and/or its functions, thus implying the mechanisms involved in regulating the abundances of the Paf1C components in altered gene expression and hence cellular pathologies. Towards finding the mechanisms associated with the abundances of the Paf1C components, we analyzed here whether the Paf1C components are regulated via targeted ubiquitylation and 26S proteasomal degradation. We find that the Paf1C components except Paf1 do not undergo the 26S proteasomal degradation in both yeast and humans. Paf1 is found to be regulated by the ubiquitin-proteasome system (UPS) in yeast and humans. Alteration of such regulation changes Paf1's abundance, leading to aberrant gene expression. Intriguingly, while the Rtf1 component of Paf1C does not undergo the 26S proteasomal degradation, it is found to be ubiquitylated, suggesting that Rtf1 ubiquitylation could be engaged in Paf1C assembly and/or functions. Collectively, our results reveal distinct UPS regulation of the Paf1C components, Paf1 and Rtf1, in a proteolysis-dependent and -independent manners, respectively, with functional implications.
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Affiliation(s)
- Priyanka Barman
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Jannatul Ferdoush
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Amala Kaja
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Pritam Chakraborty
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Bhawana Uprety
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Rhea Bhaumik
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Risa Bhaumik
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Sukesh R Bhaumik
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA.
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5
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Zhang Q, Kim W, Panina S, Mayfield JE, Portz B, Zhang YJ. Variation of C-terminal domain governs RNA polymerase II genomic locations and alternative splicing in eukaryotic transcription. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.01.573828. [PMID: 38260389 PMCID: PMC10802280 DOI: 10.1101/2024.01.01.573828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The C-terminal domain of RPB1 (CTD) orchestrates transcription by recruiting regulators to RNA Pol II upon phosphorylation. Recent insights highlight the pivotal role of CTD in driving condensate formation on gene loci. Yet, the molecular mechanism behind how CTD-mediated recruitment of transcriptional regulators influences condensates formation remains unclear. Our study unveils that phosphorylation reversibly dissolves phase separation induced by the unphosphorylated CTD. Phosphorylated CTD, upon specific association with transcription regulatory proteins, forms distinct condensates from unphosphorylated CTD. Function studies demonstrate CTD variants with diverse condensation properties in vitro exhibit difference in promoter binding and mRNA co-processing in cells. Notably, varying CTD lengths lead to alternative splicing outcomes impacting cellular growth, linking the evolution of CTD variation/length with the complexity of splicing from yeast to human. These findings provide compelling evidence for a model wherein post-translational modification enables the transition of functionally specialized condensates, highlighting a co-evolution link between CTD condensation and splicing.
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Affiliation(s)
- Qian Zhang
- Department of Molecular Biosciences, University of Texas, Austin, Texas, 78712
| | - Wantae Kim
- McKetta Department of Chemical Engineering, University of Texas, Austin, Texas, 78712
| | - Svetlana Panina
- Department of Molecular Biosciences, University of Texas, Austin, Texas, 78712
| | - Joshua E. Mayfield
- Department of Pharmacology, Chemistry, and Biochemistry, and Cellular and Molecular Medicine, University of California San Diego, La Jolla, California 92093
| | - Bede Portz
- Dewpoint Therapeutics, 451 D Street, Boston, Massachusetts 02210
| | - Y. Jessie Zhang
- Department of Molecular Biosciences, University of Texas, Austin, Texas, 78712
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6
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Appel LM, Benedum J, Engl M, Platzer S, Schleiffer A, Strobl X, Slade D. SPOC domain proteins in health and disease. Genes Dev 2023; 37:140-170. [PMID: 36927757 PMCID: PMC10111866 DOI: 10.1101/gad.350314.122] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
Since it was first described >20 yr ago, the SPOC domain (Spen paralog and ortholog C-terminal domain) has been identified in many proteins all across eukaryotic species. SPOC-containing proteins regulate gene expression on various levels ranging from transcription to RNA processing, modification, export, and stability, as well as X-chromosome inactivation. Their manifold roles in controlling transcriptional output implicate them in a plethora of developmental processes, and their misregulation is often associated with cancer. Here, we provide an overview of the biophysical properties of the SPOC domain and its interaction with phosphorylated binding partners, the phylogenetic origin of SPOC domain proteins, the diverse functions of mammalian SPOC proteins and their homologs, the mechanisms by which they regulate differentiation and development, and their roles in cancer.
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Affiliation(s)
- Lisa-Marie Appel
- Department of Radiation Oncology, Medical University of Vienna, 1090 Vienna, Austria
- Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
- Department of Medical Biochemistry, Medical University of Vienna, Max Perutz Laboratories, Vienna Biocenter, 1030 Vienna, Austria
| | - Johannes Benedum
- Department of Radiation Oncology, Medical University of Vienna, 1090 Vienna, Austria
- Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
- Department of Medical Biochemistry, Medical University of Vienna, Max Perutz Laboratories, Vienna Biocenter, 1030 Vienna, Austria
- Vienna Biocenter PhD Program, a Doctoral School of the University of Vienna and Medical University of Vienna, 1030 Vienna, Austria
| | - Magdalena Engl
- Department of Radiation Oncology, Medical University of Vienna, 1090 Vienna, Austria
- Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
- Department of Medical Biochemistry, Medical University of Vienna, Max Perutz Laboratories, Vienna Biocenter, 1030 Vienna, Austria
- Vienna Biocenter PhD Program, a Doctoral School of the University of Vienna and Medical University of Vienna, 1030 Vienna, Austria
| | - Sebastian Platzer
- Department of Medical Biochemistry, Medical University of Vienna, Max Perutz Laboratories, Vienna Biocenter, 1030 Vienna, Austria
| | - Alexander Schleiffer
- Research Institute of Molecular Pathology (IMP), 1030 Vienna, Austria
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Xué Strobl
- Department of Medical Biochemistry, Medical University of Vienna, Max Perutz Laboratories, Vienna Biocenter, 1030 Vienna, Austria
- Vienna Biocenter PhD Program, a Doctoral School of the University of Vienna and Medical University of Vienna, 1030 Vienna, Austria
| | - Dea Slade
- Department of Radiation Oncology, Medical University of Vienna, 1090 Vienna, Austria;
- Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
- Department of Medical Biochemistry, Medical University of Vienna, Max Perutz Laboratories, Vienna Biocenter, 1030 Vienna, Austria
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7
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RNA-controlled nucleocytoplasmic shuttling of mRNA decay factors regulates mRNA synthesis and a novel mRNA decay pathway. Nat Commun 2022; 13:7184. [PMID: 36418294 PMCID: PMC9684461 DOI: 10.1038/s41467-022-34417-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 10/25/2022] [Indexed: 11/27/2022] Open
Abstract
mRNA level is controlled by factors that mediate both mRNA synthesis and decay, including the 5' to 3' exonuclease Xrn1. Here we show that nucleocytoplasmic shuttling of several yeast mRNA decay factors plays a key role in determining both mRNA synthesis and decay. Shuttling is regulated by RNA-controlled binding of the karyopherin Kap120 to two nuclear localization sequences (NLSs) in Xrn1, location of one of which is conserved from yeast to human. The decaying RNA binds and masks NLS1, establishing a link between mRNA decay and Xrn1 shuttling. Preventing Xrn1 import, either by deleting KAP120 or mutating the two Xrn1 NLSs, compromises transcription and, unexpectedly, also cytoplasmic decay, uncovering a cytoplasmic decay pathway that initiates in the nucleus. Most mRNAs are degraded by both pathways - the ratio between them represents a full spectrum. Importantly, Xrn1 shuttling is required for proper responses to environmental changes, e.g., fluctuating temperatures, involving proper changes in mRNA abundance and in cell proliferation rate.
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8
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Mattay J. Noncanonical metabolite RNA caps: Classification, quantification, (de)capping, and function. WILEY INTERDISCIPLINARY REVIEWS. RNA 2022; 13:e1730. [PMID: 35675554 DOI: 10.1002/wrna.1730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/11/2022] [Accepted: 03/15/2022] [Indexed: 06/15/2023]
Abstract
The 5' cap of eukaryotic mRNA is a hallmark for cellular functions from mRNA stability to translation. However, the discovery of novel 5'-terminal RNA caps derived from cellular metabolites has challenged this long-standing singularity in both eukaryotes and prokaryotes. Reminiscent of the 7-methylguanosine (m7G) cap structure, these noncanonical caps originate from abundant coenzymes such as NAD, FAD, or CoA and from metabolites like dinucleoside polyphosphates (NpnN). As of now, the significance of noncanonical RNA caps is elusive: they differ for individual transcripts, occur in distinct types of RNA, and change in response to environmental stimuli. A thorough comparison of their prevalence, quantity, and characteristics is indispensable to define the distinct classes of metabolite-capped RNAs. This is achieved by a structured analysis of all present studies covering functional, quantitative, and sequencing data which help to uncover their biological impact. The biosynthetic strategies of noncanonical RNA capping and the elaborate decapping machinery reveal the regulation and turnover of metabolite-capped RNAs. With noncanonical capping being a universal and ancient phenomenon, organisms have developed diverging strategies to adapt metabolite-derived caps to their metabolic needs, but ultimately to establish noncanonical RNA caps as another intriguing layer of RNA regulation. This article is categorized under: RNA Processing > Capping and 5' End Modifications RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Turnover and Surveillance > Regulation of RNA Stability.
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Affiliation(s)
- Johanna Mattay
- Institute of Biochemistry, University of Münster, Münster, Germany
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9
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Mittal C, Lang O, Lai WKM, Pugh BF. An integrated SAGA and TFIID PIC assembly pathway selective for poised and induced promoters. Genes Dev 2022; 36:985-1001. [PMID: 36302553 PMCID: PMC9732905 DOI: 10.1101/gad.350026.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 10/11/2022] [Indexed: 02/05/2023]
Abstract
Genome-wide, little is understood about how proteins organize at inducible promoters before and after induction and to what extent inducible and constitutive architectures depend on cofactors. We report that sequence-specific transcription factors and their tethered cofactors (e.g., SAGA [Spt-Ada-Gcn5-acetyltransferase], Mediator, TUP, NuA4, SWI/SNF, and RPD3-L) are generally bound to promoters prior to induction ("poised"), rather than recruited upon induction, whereas induction recruits the preinitiation complex (PIC) to DNA. Through depletion and/or deletion experiments, we show that SAGA does not function at constitutive promoters, although a SAGA-independent Gcn5 acetylates +1 nucleosomes there. When inducible promoters are poised, SAGA catalyzes +1 nucleosome acetylation but not PIC assembly. When induced, SAGA catalyzes acetylation, deubiquitylation, and PIC assembly. Surprisingly, SAGA mediates induction by creating a PIC that allows TFIID (transcription factor II-D) to stably associate, rather than creating a completely TFIID-independent PIC, as generally thought. These findings suggest that inducible systems, where present, are integrated with constitutive systems.
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Affiliation(s)
- Chitvan Mittal
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16801, USA
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850, USA
| | - Olivia Lang
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850, USA
| | - William K M Lai
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16801, USA
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850, USA
| | - B Franklin Pugh
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16801, USA
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850, USA
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10
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Malik I, Tseng Y, Wright SE, Zheng K, Ramaiyer P, Green KM, Todd PK. SRSF protein kinase 1 modulates RAN translation and suppresses CGG repeat toxicity. EMBO Mol Med 2021; 13:e14163. [PMID: 34542927 PMCID: PMC8573603 DOI: 10.15252/emmm.202114163] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 08/28/2021] [Accepted: 08/30/2021] [Indexed: 11/20/2022] Open
Abstract
Transcribed CGG repeat expansions cause neurodegeneration in Fragile X-associated tremor/ataxia syndrome (FXTAS). CGG repeat RNAs sequester RNA-binding proteins (RBPs) into nuclear foci and undergo repeat-associated non-AUG (RAN) translation into toxic peptides. To identify proteins involved in these processes, we employed a CGG repeat RNA-tagging system to capture repeat-associated RBPs by mass spectrometry in mammalian cells. We identified several SR (serine/arginine-rich) proteins that interact selectively with CGG repeats basally and under cellular stress. These proteins modify toxicity in a Drosophila model of FXTAS. Pharmacologic inhibition of serine/arginine protein kinases (SRPKs), which alter SRSF protein phosphorylation, localization, and activity, directly inhibits RAN translation of CGG and GGGGCC repeats (associated with C9orf72 ALS/FTD) and triggers repeat RNA retention in the nucleus. Lowering SRPK expression suppressed toxicity in both FXTAS and C9orf72 ALS/FTD model flies, and SRPK inhibitors suppressed CGG repeat toxicity in rodent neurons. Together, these findings demonstrate roles for CGG repeat RNA binding proteins in RAN translation and repeat toxicity and support further evaluation of SRPK inhibitors in modulating RAN translation associated with repeat expansion disorders.
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Affiliation(s)
- Indranil Malik
- Department of NeurologyUniversity of MichiganAnn ArborMIUSA
| | - Yi‐Ju Tseng
- Department of NeurologyUniversity of MichiganAnn ArborMIUSA
- Cellular and Molecular Biology Graduate ProgramUniversity of MichiganAnn ArborMIUSA
| | - Shannon E Wright
- Department of NeurologyUniversity of MichiganAnn ArborMIUSA
- Neuroscience Graduate ProgramUniversity of MichiganAnn ArborMIUSA
| | - Kristina Zheng
- Department of NeurologyUniversity of MichiganAnn ArborMIUSA
| | | | - Katelyn M Green
- Department of NeurologyUniversity of MichiganAnn ArborMIUSA
- Cellular and Molecular Biology Graduate ProgramUniversity of MichiganAnn ArborMIUSA
| | - Peter K Todd
- Department of NeurologyUniversity of MichiganAnn ArborMIUSA
- Ann Arbor Veterans Administration HealthcareAnn ArborMIUSA
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11
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Appel LM, Franke V, Bruno M, Grishkovskaya I, Kasiliauskaite A, Kaufmann T, Schoeberl UE, Puchinger MG, Kostrhon S, Ebenwaldner C, Sebesta M, Beltzung E, Mechtler K, Lin G, Vlasova A, Leeb M, Pavri R, Stark A, Akalin A, Stefl R, Bernecky C, Djinovic-Carugo K, Slade D. PHF3 regulates neuronal gene expression through the Pol II CTD reader domain SPOC. Nat Commun 2021; 12:6078. [PMID: 34667177 PMCID: PMC8526623 DOI: 10.1038/s41467-021-26360-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 09/29/2021] [Indexed: 12/16/2022] Open
Abstract
The C-terminal domain (CTD) of the largest subunit of RNA polymerase II (Pol II) is a regulatory hub for transcription and RNA processing. Here, we identify PHD-finger protein 3 (PHF3) as a regulator of transcription and mRNA stability that docks onto Pol II CTD through its SPOC domain. We characterize SPOC as a CTD reader domain that preferentially binds two phosphorylated Serine-2 marks in adjacent CTD repeats. PHF3 drives liquid-liquid phase separation of phosphorylated Pol II, colocalizes with Pol II clusters and tracks with Pol II across the length of genes. PHF3 knock-out or SPOC deletion in human cells results in increased Pol II stalling, reduced elongation rate and an increase in mRNA stability, with marked derepression of neuronal genes. Key neuronal genes are aberrantly expressed in Phf3 knock-out mouse embryonic stem cells, resulting in impaired neuronal differentiation. Our data suggest that PHF3 acts as a prominent effector of neuronal gene regulation by bridging transcription with mRNA decay.
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Affiliation(s)
- Lisa-Marie Appel
- Department of Biochemistry and Cell Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Vedran Franke
- The Berlin Institute for Medical Systems Biology, Max Delbrück Center, Berlin, Germany
| | - Melania Bruno
- Department of Biochemistry and Cell Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Irina Grishkovskaya
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Aiste Kasiliauskaite
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Tanja Kaufmann
- Department of Biochemistry and Cell Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Ursula E Schoeberl
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Martin G Puchinger
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Sebastian Kostrhon
- Department of Biochemistry and Cell Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Carmen Ebenwaldner
- Department of Biochemistry and Cell Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Marek Sebesta
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Etienne Beltzung
- Department of Biochemistry and Cell Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Karl Mechtler
- Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, Vienna Biocenter (VBC), Vienna, Austria
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), Vienna, Austria
| | - Gen Lin
- Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, Vienna Biocenter (VBC), Vienna, Austria
| | - Anna Vlasova
- Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, Vienna Biocenter (VBC), Vienna, Austria
| | - Martin Leeb
- Department of Microbiology, Immunobiology and Genetics, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | - Rushad Pavri
- Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, Vienna Biocenter (VBC), Vienna, Austria
| | - Alexander Stark
- Research Institute of Molecular Pathology (IMP), Campus-Vienna-Biocenter 1, Vienna Biocenter (VBC), Vienna, Austria
| | - Altuna Akalin
- The Berlin Institute for Medical Systems Biology, Max Delbrück Center, Berlin, Germany
| | - Richard Stefl
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Carrie Bernecky
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, Klosterneuburg, Austria
| | - Kristina Djinovic-Carugo
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
- Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
| | - Dea Slade
- Department of Biochemistry and Cell Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria.
- Department of Radiation Oncology, Medical University of Vienna, Vienna, Austria.
- Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria.
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12
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LeBlanc BM, Moreno RY, Escobar EE, Venkat Ramani MK, Brodbelt JS, Zhang Y. What's all the phos about? Insights into the phosphorylation state of the RNA polymerase II C-terminal domain via mass spectrometry. RSC Chem Biol 2021; 2:1084-1095. [PMID: 34458825 PMCID: PMC8341212 DOI: 10.1039/d1cb00083g] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 06/03/2021] [Indexed: 12/31/2022] Open
Abstract
RNA polymerase II (RNAP II) is one of the primary enzymes responsible for expressing protein-encoding genes and some small nuclear RNAs. The enigmatic carboxy-terminal domain (CTD) of RNAP II and its phosphorylation state are critically important in regulating transcription in vivo. Early methods of identifying phosphorylation on the CTD heptad were plagued by issues of low specificity and ambiguous signals. However, advancements in the field of mass spectrometry (MS) have presented the opportunity to gain new insights into well-studied processes as well as explore new frontiers in transcription. By using MS, residues which are modified within the CTD heptad and across repeats are now able to be pinpointed. Likewise, identification of kinase and phosphatase specificity towards residues of the CTD has reached a new level of accuracy. Now, MS is being used to investigate the crosstalk between modified residues of the CTD and may be a critical technique for understanding how phosphorylation plays a role in the new LLPS model of transcription. Herein, we discuss the development of various MS techniques and evaluate their capabilities. By highlighting the pros and cons of each technique, we aim to provide future investigators with a comprehensive overview of how MS can be used to investigate the complexities of RNAP-II mediated transcription.
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Affiliation(s)
- Blase M LeBlanc
- Department of Molecular Biosciences, University of Texas Austin USA
| | - R Yvette Moreno
- Department of Molecular Biosciences, University of Texas Austin USA
| | | | | | | | - Yan Zhang
- Department of Molecular Biosciences, University of Texas Austin USA
- Institute of Cellular and Molecular Biology, University of Texas Austin USA
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13
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Francette AM, Tripplehorn SA, Arndt KM. The Paf1 Complex: A Keystone of Nuclear Regulation Operating at the Interface of Transcription and Chromatin. J Mol Biol 2021; 433:166979. [PMID: 33811920 PMCID: PMC8184591 DOI: 10.1016/j.jmb.2021.166979] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/21/2021] [Accepted: 03/24/2021] [Indexed: 12/14/2022]
Abstract
The regulation of transcription by RNA polymerase II is closely intertwined with the regulation of chromatin structure. A host of proteins required for the disassembly, reassembly, and modification of nucleosomes interacts with Pol II to aid its movement and counteract its disruptive effects on chromatin. The highly conserved Polymerase Associated Factor 1 Complex, Paf1C, travels with Pol II and exerts control over transcription elongation and chromatin structure, while broadly impacting the transcriptome in both single cell and multicellular eukaryotes. Recent studies have yielded exciting new insights into the mechanisms by which Paf1C regulates transcription elongation, epigenetic modifications, and post-transcriptional steps in eukaryotic gene expression. Importantly, these functional studies are now supported by an extensive foundation of high-resolution structural information, providing intimate views of Paf1C and its integration into the larger Pol II elongation complex. As a global regulatory factor operating at the interface between chromatin and transcription, the impact of Paf1C is broad and its influence reverberates into other domains of nuclear regulation, including genome stability, telomere maintenance, and DNA replication.
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Affiliation(s)
- Alex M Francette
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Sarah A Tripplehorn
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Karen M Arndt
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States.
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14
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Dhoondia Z, Elewa H, Malik M, Arif Z, Pique-Regi R, Ansari A. A termination-independent role of Rat1 in cotranscriptional splicing. Nucleic Acids Res 2021; 49:5520-5536. [PMID: 33978753 PMCID: PMC8191773 DOI: 10.1093/nar/gkab339] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 04/12/2021] [Accepted: 04/19/2021] [Indexed: 01/18/2023] Open
Abstract
Rat1 is a 5′→3′ exoribonuclease in budding yeast. It is a highly conserved protein with homologs being present in fission yeast, flies, worms, mice and humans. Rat1 and its human homolog Xrn2 have been implicated in multiple nuclear processes. Here we report a novel role of Rat1 in mRNA splicing. We observed an increase in the level of unspliced transcripts in mutants of Rat1. Accumulation of unspliced transcripts was not due to the surveillance role of Rat1 in degrading unspliced mRNA, or an indirect effect of Rat1 function in termination of transcription or on the level of splicing factors in the cell, or due to an increased elongation rate in Rat1 mutants. ChIP-Seq analysis revealed Rat1 crosslinking to the introns of a subset of yeast genes. Mass spectrometry and coimmunoprecipitation revealed an interaction of Rat1 with the Clf1, Isy1, Yju2, Prp43 and Sub2 splicing factors. Furthermore, recruitment of splicing factors on the intron was compromised in the Rat1 mutant. Based on these findings we propose that Rat1 has a novel role in splicing of mRNA in budding yeast. Rat1, however, is not a general splicing factor as it crosslinks to only long introns with an average length of 400 nucleotides.
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Affiliation(s)
- Zuzer Dhoondia
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - Hesham Elewa
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - Marva Malik
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - Zahidur Arif
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - Roger Pique-Regi
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, 540 East Canfield, Detroit, MI 48201, USA
| | - Athar Ansari
- To whom correspondence should be addressed. Tel: +1 313 577 9251; Fax: +1 313 571 6891;
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15
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Viktorovskaya O, Chuang J, Jain D, Reim NI, López-Rivera F, Murawska M, Spatt D, Churchman LS, Park PJ, Winston F. Essential histone chaperones collaborate to regulate transcription and chromatin integrity. Genes Dev 2021; 35:698-712. [PMID: 33888559 PMCID: PMC8091981 DOI: 10.1101/gad.348431.121] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 03/30/2021] [Indexed: 12/15/2022]
Abstract
Histone chaperones are critical for controlling chromatin integrity during transcription, DNA replication, and DNA repair. Three conserved and essential chaperones, Spt6, Spn1/Iws1, and FACT, associate with elongating RNA polymerase II and interact with each other physically and/or functionally; however, there is little understanding of their individual functions or their relationships with each other. In this study, we selected for suppressors of a temperature-sensitive spt6 mutation that disrupts the Spt6-Spn1 physical interaction and that also causes both transcription and chromatin defects. This selection identified novel mutations in FACT. Surprisingly, suppression by FACT did not restore the Spt6-Spn1 interaction, based on coimmunoprecipitation, ChIP, and mass spectrometry experiments. Furthermore, suppression by FACT bypassed the complete loss of Spn1. Interestingly, the FACT suppressor mutations cluster along the FACT-nucleosome interface, suggesting that they alter FACT-nucleosome interactions. In agreement with this observation, we showed that the spt6 mutation that disrupts the Spt6-Spn1 interaction caused an elevated level of FACT association with chromatin, while the FACT suppressors reduced the level of FACT-chromatin association, thereby restoring a normal Spt6-FACT balance on chromatin. Taken together, these studies reveal previously unknown regulation between histone chaperones that is critical for their essential in vivo functions.
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Affiliation(s)
- Olga Viktorovskaya
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - James Chuang
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Dhawal Jain
- Department of Biomedical Informatics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Natalia I Reim
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Francheska López-Rivera
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Magdalena Murawska
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Dan Spatt
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - L Stirling Churchman
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Peter J Park
- Department of Biomedical Informatics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Fred Winston
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
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16
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García-Martínez J, Pérez-Martínez ME, Pérez-Ortín JE, Alepuz P. Recruitment of Xrn1 to stress-induced genes allows efficient transcription by controlling RNA polymerase II backtracking. RNA Biol 2020; 18:1458-1474. [PMID: 33258404 DOI: 10.1080/15476286.2020.1857521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A new paradigm has emerged proposing that the crosstalk between nuclear transcription and cytoplasmic mRNA stability keeps robust mRNA levels in cells under steady-state conditions. A key piece in this crosstalk is the highly conserved 5'-3' RNA exonuclease Xrn1, which degrades most cytoplasmic mRNAs but also associates with nuclear chromatin to activate transcription by not well-understood mechanisms. Here, we investigated the role of Xrn1 in the transcriptional response of Saccharomyces cerevisiae cells to osmotic stress. We show that a lack of Xrn1 results in much lower transcriptional induction of the upregulated genes but in similar high levels of their transcripts because of parallel mRNA stabilization. Unexpectedly, lower transcription in xrn1 occurs with a higher accumulation of RNA polymerase II (RNAPII) at stress-inducible genes, suggesting that this polymerase remains inactive backtracked. Xrn1 seems to be directly implicated in the formation of a competent elongation complex because Xrn1 is recruited to the osmotic stress-upregulated genes in parallel with the RNAPII complex, and both are dependent on the mitogen-activated protein kinase Hog1. Our findings extend the role of Xrn1 in preventing the accumulation of inactive RNAPII at highly induced genes to other situations of rapid and strong transcriptional upregulation.
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Affiliation(s)
- José García-Martínez
- ERI Biotecmed, Facultad De Ciencias Biológicas, Universitat De València, Burjassot, Spain.,Departamento De Genética, Facultad De Ciencias Biológicas, Universitat De València, Burjassot, Spain
| | - María E Pérez-Martínez
- ERI Biotecmed, Facultad De Ciencias Biológicas, Universitat De València, Burjassot, Spain.,Departamento De Bioquímica Y Biología Molecular, Facultad De Ciencias Biológicas, Universitat De València, Burjassot, Spain
| | - José E Pérez-Ortín
- ERI Biotecmed, Facultad De Ciencias Biológicas, Universitat De València, Burjassot, Spain.,Departamento De Bioquímica Y Biología Molecular, Facultad De Ciencias Biológicas, Universitat De València, Burjassot, Spain
| | - Paula Alepuz
- ERI Biotecmed, Facultad De Ciencias Biológicas, Universitat De València, Burjassot, Spain.,Departamento De Bioquímica Y Biología Molecular, Facultad De Ciencias Biológicas, Universitat De València, Burjassot, Spain
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17
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Zhang Y, Kuster D, Schmidt T, Kirrmaier D, Nübel G, Ibberson D, Benes V, Hombauer H, Knop M, Jäschke A. Extensive 5'-surveillance guards against non-canonical NAD-caps of nuclear mRNAs in yeast. Nat Commun 2020; 11:5508. [PMID: 33139726 PMCID: PMC7606564 DOI: 10.1038/s41467-020-19326-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 09/24/2020] [Indexed: 12/16/2022] Open
Abstract
The ubiquitous redox coenzyme nicotinamide adenine dinucleotide (NAD) acts as a non-canonical cap structure on prokaryotic and eukaryotic ribonucleic acids. Here we find that in budding yeast, NAD-RNAs are abundant (>1400 species), short (<170 nt), and mostly correspond to mRNA 5′-ends. The modification percentage of transcripts is low (<5%). NAD incorporation occurs mainly during transcription initiation by RNA polymerase II, which uses distinct promoters with a YAAG core motif for this purpose. Most NAD-RNAs are 3′-truncated. At least three decapping enzymes, Rai1, Dxo1, and Npy1, guard against NAD-RNA at different cellular locations, targeting overlapping transcript populations. NAD-mRNAs are not translatable in vitro. Our work indicates that in budding yeast, most of the NAD incorporation into RNA seems to be disadvantageous to the cell, which has evolved a diverse surveillance machinery to prematurely terminate, decap and reject NAD-RNAs. NAD (nicotinamide adenine dinucleotide) acts as a non-canonical RNA cap structure in bacteria and eukaryotes. Here the authors demonstrate the whole landscape of budding yeast NAD-RNAs which are subject to diverse surveillance pathways, suggesting that NAD caps in budding yeast are mostly dysfunctional.
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Affiliation(s)
- Yaqing Zhang
- Institute of Pharmacy and Molecular Biotechnology (IPMB), Heidelberg University, 69120, Heidelberg, Germany
| | - David Kuster
- Institute of Pharmacy and Molecular Biotechnology (IPMB), Heidelberg University, 69120, Heidelberg, Germany
| | - Tobias Schmidt
- DNA Repair Mechanisms and Cancer, German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany
| | - Daniel Kirrmaier
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, 69120, Heidelberg, Germany.,Cell Morphogenesis and Signal Transduction, German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, 69120, Heidelberg, Germany
| | - Gabriele Nübel
- Institute of Pharmacy and Molecular Biotechnology (IPMB), Heidelberg University, 69120, Heidelberg, Germany
| | - David Ibberson
- Deep Sequencing Core Facility, CellNetworks, Heidelberg University, 69120, Heidelberg, Germany
| | - Vladimir Benes
- Genomics Core Facility, European Molecular Biology Laboratory (EMBL), 69117, Heidelberg, Germany
| | - Hans Hombauer
- DNA Repair Mechanisms and Cancer, German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany.,Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, 69120, Heidelberg, Germany
| | - Michael Knop
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, 69120, Heidelberg, Germany.,Cell Morphogenesis and Signal Transduction, German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, 69120, Heidelberg, Germany
| | - Andres Jäschke
- Institute of Pharmacy and Molecular Biotechnology (IPMB), Heidelberg University, 69120, Heidelberg, Germany.
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18
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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: 50] [Impact Index Per Article: 12.5] [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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19
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Yeast Spt6 Reads Multiple Phosphorylation Patterns of RNA Polymerase II C-Terminal Domain In Vitro. J Mol Biol 2020; 432:4092-4107. [PMID: 32439331 PMCID: PMC7327521 DOI: 10.1016/j.jmb.2020.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 12/21/2022]
Abstract
Transcription elongation factor Spt6 associates with RNA polymerase II (RNAP II) via a tandem SH2 (tSH2) domain. The mechanism and significance of the RNAP II–Spt6 interaction is still unclear. Recently, it was proposed that Spt6-tSH2 is recruited via a newly described phosphorylated linker between the Rpb1 core and its C-terminal domain (CTD). Here, we report binding studies with isolated tSH2 of Spt6 (Spt6-tSH2) and Spt6 lacking the first unstructured 297 residues (Spt6ΔN) with a minimal CTD substrate of two repetitive heptads phosphorylated at different sites. The data demonstrate that Spt6 also binds the phosphorylated CTD, a site that was originally proposed as a recognition epitope. We also show that an extended CTD substrate harboring 13 repetitive heptads of the tyrosine-phosphorylated CTD binds Spt6-tSH2 and Spt6ΔN with tighter affinity than the minimal CTD substrate. The enhanced binding is achieved by avidity originating from multiple phosphorylation marks present in the CTD. Interestingly, we found that the steric effects of additional domains in the Spt6ΔN construct partially obscure the binding of the tSH2 domain to the multivalent ligand. We show that Spt6-tSH2 binds various phosphorylation patterns in the CTD and found that the studied combinations of phospho-CTD marks (1,2; 1,5; 2,4; and 2,7) all facilitate the interaction of CTD with Spt6. Our structural studies reveal a plasticity of the tSH2 binding pockets that enables the accommodation of CTDs with phosphorylation marks in different registers. High-affinity Pol II CTD-binding by Spt6 is achieved by avidity originating from multiple phosphorylation marks presented in the CTD, suggesting how phosphorylation levels fine-tune the CTD interactome. Structure of RNAP II CTD bound with tandem SH2 domain of Spt6 reveals how phosphorylated CTD is recognized. Isolated tSH2 of Spt6 binds the extended CTD substrate with tighter affinity than nearly full-length Spt6, suggesting that the steric effects of additional domains in Spt6 influence the binding of the tSH2 domain to the multivalent CTD ligand.
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20
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Han Z, Jasnovidova O, Haidara N, Tudek A, Kubicek K, Libri D, Stefl R, Porrua O. Termination of non-coding transcription in yeast relies on both an RNA Pol II CTD interaction domain and a CTD-mimicking region in Sen1. EMBO J 2020; 39:e101548. [PMID: 32107786 PMCID: PMC7110113 DOI: 10.15252/embj.2019101548] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 01/23/2020] [Accepted: 01/31/2020] [Indexed: 12/12/2022] Open
Abstract
Pervasive transcription is a widespread phenomenon leading to the production of a plethora of non‐coding RNAs (ncRNAs) without apparent function. Pervasive transcription poses a threat to proper gene expression that needs to be controlled. In yeast, the highly conserved helicase Sen1 restricts pervasive transcription by inducing termination of non‐coding transcription. However, the mechanisms underlying the specific function of Sen1 at ncRNAs are poorly understood. Here, we identify a motif in an intrinsically disordered region of Sen1 that mimics the phosphorylated carboxy‐terminal domain (CTD) of RNA polymerase II, and structurally characterize its recognition by the CTD‐interacting domain of Nrd1, an RNA‐binding protein that binds specific sequences in ncRNAs. In addition, we show that Sen1‐dependent termination strictly requires CTD recognition by the N‐terminal domain of Sen1. We provide evidence that the Sen1‐CTD interaction does not promote initial Sen1 recruitment, but rather enhances Sen1 capacity to induce the release of paused RNAPII from the DNA. Our results shed light on the network of protein–protein interactions that control termination of non‐coding transcription by Sen1.
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Affiliation(s)
- Zhong Han
- Université de Paris, CNRS, Institut Jacques Monod, Paris, France.,Université Paris-Saclay, Yvette, France
| | - Olga Jasnovidova
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Nouhou Haidara
- Université de Paris, CNRS, Institut Jacques Monod, Paris, France.,Université Paris-Saclay, Yvette, France
| | - Agnieszka Tudek
- Université de Paris, CNRS, Institut Jacques Monod, Paris, France
| | - Karel Kubicek
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Domenico Libri
- Université de Paris, CNRS, Institut Jacques Monod, Paris, France
| | - Richard Stefl
- CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Odil Porrua
- Université de Paris, CNRS, Institut Jacques Monod, Paris, France
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21
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Begley V, Corzo D, Jordán-Pla A, Cuevas-Bermúdez A, Miguel-Jiménez LD, Pérez-Aguado D, Machuca-Ostos M, Navarro F, Chávez MJ, Pérez-Ortín JE, Chávez S. The mRNA degradation factor Xrn1 regulates transcription elongation in parallel to Ccr4. Nucleic Acids Res 2019; 47:9524-9541. [PMID: 31392315 PMCID: PMC6765136 DOI: 10.1093/nar/gkz660] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 06/26/2019] [Accepted: 07/17/2019] [Indexed: 01/05/2023] Open
Abstract
Co-transcriptional imprinting of mRNA by Rpb4 and Rpb7 subunits of RNA polymerase II (RNAPII) and by the Ccr4-Not complex conditions its post-transcriptional fate. In turn, mRNA degradation factors like Xrn1 are able to influence RNAPII-dependent transcription, making a feedback loop that contributes to mRNA homeostasis. In this work, we have used repressible yeast GAL genes to perform accurate measurements of transcription and mRNA degradation in a set of mutants. This genetic analysis uncovered a link from mRNA decay to transcription elongation. We combined this experimental approach with computational multi-agent modelling and tested different possibilities of Xrn1 and Ccr4 action in gene transcription. This double strategy brought us to conclude that both Xrn1-decaysome and Ccr4-Not regulate RNAPII elongation, and that they do it in parallel. We validated this conclusion measuring TFIIS genome-wide recruitment to elongating RNAPII. We found that xrn1Δ and ccr4Δ exhibited very different patterns of TFIIS versus RNAPII occupancy, which confirmed their distinct role in controlling transcription elongation. We also found that the relative influence of Xrn1 and Ccr4 is different in the genes encoding ribosomal proteins as compared to the rest of the genome.
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Affiliation(s)
- Victoria Begley
- Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville 41012, Spain
| | - Daniel Corzo
- Escuela Técnica Superior de Informática, Universidad de Sevilla, Seville 41012, Spain
| | - Antonio Jordán-Pla
- E.R.I. Biotecmed, Universitat de València; Burjassot, Valencia 46100, Spain
| | - Abel Cuevas-Bermúdez
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Universidad de Jaén, Jaén 23071, Spain
| | - Lola de Miguel-Jiménez
- Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville 41012, Spain
| | - David Pérez-Aguado
- Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville 41012, Spain
| | - Mercedes Machuca-Ostos
- Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville 41012, Spain
| | - Francisco Navarro
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Universidad de Jaén, Jaén 23071, Spain
| | - María José Chávez
- Departamento de Matemática Aplicada I and Instituto de Matemáticas, Universidad de Sevilla, Seville 41012, Spain
| | - José E Pérez-Ortín
- E.R.I. Biotecmed, Universitat de València; Burjassot, Valencia 46100, Spain
| | - Sebastián Chávez
- Instituto de Biomedicina de Sevilla, Universidad de Sevilla-CSIC-Hospital Universitario V. del Rocío, Seville 41012, Spain
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22
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Portz B, Shorter J. Switching Condensates: The CTD Code Goes Liquid. Trends Biochem Sci 2019; 45:1-3. [PMID: 31734037 DOI: 10.1016/j.tibs.2019.10.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 10/22/2019] [Accepted: 10/24/2019] [Indexed: 10/25/2022]
Abstract
Condensates containing RNA polymerase II (Pol II) materialize at sites of active transcription. Young and coworkers now establish that C-terminal domain phosphorylation regulates Pol II partitioning into distinct condensates connected with transcription initiation or splicing. This advance hints that distinct condensates with specialized functional compositions might choreograph distinct stages of transcription.
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Affiliation(s)
- Bede Portz
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.
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23
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Yu X, Martin PGP, Michaels SD. BORDER proteins protect expression of neighboring genes by promoting 3' Pol II pausing in plants. Nat Commun 2019; 10:4359. [PMID: 31554790 PMCID: PMC6761125 DOI: 10.1038/s41467-019-12328-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 08/30/2019] [Indexed: 12/18/2022] Open
Abstract
Ensuring that one gene's transcription does not inappropriately affect the expression of its neighbors is a fundamental challenge to gene regulation in a genomic context. In plants, which lack homologs of animal insulator proteins, the mechanisms that prevent transcriptional interference are not well understood. Here we show that BORDER proteins are enriched in intergenic regions and prevent interference between closely spaced genes on the same strand by promoting the 3' pausing of RNA polymerase II at the upstream gene. In the absence of BORDER proteins, 3' pausing associated with the upstream gene is reduced and shifts into the promoter region of the downstream gene. This is consistent with a model in which BORDER proteins inhibit transcriptional interference by preventing RNA polymerase from intruding into the promoters of downstream genes.
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Affiliation(s)
- Xuhong Yu
- Department of Biology, Indiana University, 915 East Third Street, Bloomington, IN, 47405, USA
| | - Pascal G P Martin
- Department of Biology, Indiana University, 915 East Third Street, Bloomington, IN, 47405, USA.,Toxalim (Research Centre in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, 31027, Toulouse, France
| | - Scott D Michaels
- Department of Biology, Indiana University, 915 East Third Street, Bloomington, IN, 47405, USA.
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24
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Burger K, Ketley RF, Gullerova M. Beyond the Trinity of ATM, ATR, and DNA-PK: Multiple Kinases Shape the DNA Damage Response in Concert With RNA Metabolism. Front Mol Biosci 2019; 6:61. [PMID: 31428617 PMCID: PMC6688092 DOI: 10.3389/fmolb.2019.00061] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 07/11/2019] [Indexed: 12/22/2022] Open
Abstract
Our genome is constantly exposed to endogenous and exogenous sources of DNA damage resulting in various alterations of the genetic code. DNA double-strand breaks (DSBs) are considered one of the most cytotoxic lesions. Several types of repair pathways act to repair DNA damage and maintain genome stability. In the canonical DNA damage response (DDR) DSBs are recognized by the sensing kinases Ataxia-telangiectasia mutated (ATM), Ataxia-telangiectasia and Rad3-related (ATR), and DNA-dependent protein kinase (DNA-PK), which initiate a cascade of kinase-dependent amplification steps known as DSB signaling. Recent evidence suggests that efficient recognition and repair of DSBs relies on the transcription and processing of non-coding (nc)RNA molecules by RNA polymerase II (RNAPII) and the RNA interference (RNAi) factors Drosha and Dicer. Multiple kinases influence the phosphorylation status of both the RNAPII carboxy-terminal domain (CTD) and Dicer in order to regulate RNA-dependent DSBs repair. The importance of kinase signaling and RNA processing in the DDR is highlighted by the regulation of p53-binding protein (53BP1), a key regulator of DSB repair pathway choice between homologous recombination (HR) and non-homologous end joining (NHEJ). Additionally, emerging evidence suggests that RNA metabolic enzymes also play a role in the repair of other types of DNA damage, including the DDR to ultraviolet radiation (UVR). RNAi factors are also substrates for mitogen-activated protein kinase (MAPK) signaling and mediate the turnover of ncRNA during nucleotide excision repair (NER) in response to UVR. Here, we review kinase-dependent phosphorylation events on RNAPII, Drosha and Dicer, and 53BP1 that modulate the key steps of the DDR to DSBs and UVR, suggesting an intimate link between the DDR and RNA metabolism.
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Affiliation(s)
| | | | - Monika Gullerova
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
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25
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Ellison MA, Lederer AR, Warner MH, Mavrich TN, Raupach EA, Heisler LE, Nislow C, Lee MT, Arndt KM. The Paf1 Complex Broadly Impacts the Transcriptome of Saccharomyces cerevisiae. Genetics 2019; 212:711-728. [PMID: 31092540 PMCID: PMC6614894 DOI: 10.1534/genetics.119.302262] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/13/2019] [Indexed: 12/12/2022] Open
Abstract
The Polymerase Associated Factor 1 complex (Paf1C) is a multifunctional regulator of eukaryotic gene expression important for the coordination of transcription with chromatin modification and post-transcriptional processes. In this study, we investigated the extent to which the functions of Paf1C combine to regulate the Saccharomyces cerevisiae transcriptome. While previous studies focused on the roles of Paf1C in controlling mRNA levels, here, we took advantage of a genetic background that enriches for unstable transcripts, and demonstrate that deletion of PAF1 affects all classes of Pol II transcripts including multiple classes of noncoding RNAs (ncRNAs). By conducting a de novo differential expression analysis independent of gene annotations, we found that Paf1 positively and negatively regulates antisense transcription at multiple loci. Comparisons with nascent transcript data revealed that many, but not all, changes in RNA levels detected by our analysis are due to changes in transcription instead of post-transcriptional events. To investigate the mechanisms by which Paf1 regulates protein-coding genes, we focused on genes involved in iron and phosphate homeostasis, which were differentially affected by PAF1 deletion. Our results indicate that Paf1 stimulates phosphate gene expression through a mechanism that is independent of any individual Paf1C-dependent histone modification. In contrast, the inhibition of iron gene expression by Paf1 correlates with a defect in H3 K36 trimethylation. Finally, we showed that one iron regulon gene, FET4, is coordinately controlled by Paf1 and transcription of upstream noncoding DNA. Together, these data identify roles for Paf1C in controlling both coding and noncoding regions of the yeast genome.
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Affiliation(s)
- Mitchell A Ellison
- Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260
| | - Alex R Lederer
- Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260
| | - Marcie H Warner
- Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260
| | - Travis N Mavrich
- Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260
| | - Elizabeth A Raupach
- Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260
| | - Lawrence E Heisler
- Terrance Donnelly Centre and Banting and Best Department of Medical Research, University of Toronto, Ontario M5S 3E1, Canada
| | - Corey Nislow
- Department of Pharmaceutical Sciences, University of British Columbia, Vancouver BC V6T 1Z3, British Columbia, Canada
| | - Miler T Lee
- Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260
| | - Karen M Arndt
- Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260
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26
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Efficient and robust preparation of tyrosine phosphorylated intrinsically disordered proteins. Biotechniques 2019; 67:16-22. [PMID: 31092000 DOI: 10.2144/btn-2019-0033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Intrinsically disordered proteins (IDPs) are subject to post-translational modifications. This allows the same polypeptide to be involved in different interaction networks with different consequences, ranging from regulatory signalling networks to the formation of membrane-less organelles. We report a robust method for co-expression of modification enzyme and SUMO-tagged IDPs with a subsequent purification procedure that allows for the production of modified IDP. The robustness of our protocol is demonstrated using a challenging system: RNA polymerase II C-terminal domain (CTD); that is, a low-complexity repetitive region with multiple phosphorylation sites. In vitro phosphorylation approaches fail to yield multiple-site phosphorylated CTD, whereas our in vivo protocol allows the rapid production of near homogeneous phosphorylated CTD at a low cost. These samples can be used in functional and structural studies.
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Burriss KH, Mosley AL. Methods review: Mass spectrometry analysis of RNAPII complexes. Methods 2019; 159-160:105-114. [PMID: 30902665 DOI: 10.1016/j.ymeth.2019.03.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/04/2019] [Accepted: 03/17/2019] [Indexed: 12/20/2022] Open
Abstract
RNA Polymerase II (RNAPII) is responsible for transcribing multiple RNA species throughout eukaryotes. A variety of protein-protein interactions occur throughout the transcription cycle for coordinated regulation of transcription initiation, elongation, and/or termination. Taking a proteomics approach to study RNAPII transcription thereby offers a comprehensive view of both RNAPII biology and the variety of proteins that regulate the process itself. This review will focus on how mass spectrometry (MS) methods have expanded understanding of RNAPII and its transcription-regulatory interaction partners. The application of affinity purification mass spectrometry has led to the discovery of a number of novel groups of proteins that regulate an array of RNAPII biology ranging from nuclear import to regulation of phosphorylation state. Additionally, a number of methods have been developed using mass spectrometry to measure protein subunit stoichiometry within and across protein complexes and to perform various types of architectural analysis using structural proteomics approaches. The key methods that we will focus on related to RNAPII mass spectrometry analyses include: affinity purification mass spectrometry, protein post-translational modification analysis, crosslinking mass spectrometry, and native mass spectrometry.
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Affiliation(s)
- Katlyn Hughes Burriss
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46402, United States
| | - Amber L Mosley
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46402, United States; Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN 46402, United States.
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28
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Pause & go: from the discovery of RNA polymerase pausing to its functional implications. Curr Opin Cell Biol 2017; 46:72-80. [PMID: 28363125 DOI: 10.1016/j.ceb.2017.03.002] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/06/2017] [Accepted: 03/07/2017] [Indexed: 12/25/2022]
Abstract
The synthesis of nascent RNA is a discontinuous process in which phases of productive elongation by RNA polymerase are interrupted by frequent pauses. Transcriptional pausing was first observed decades ago, but was long considered to be a special feature of transcription at certain genes. This view was challenged when studies using genome-wide approaches revealed that RNA polymerase II pauses at promoter-proximal regions in large sets of genes in Drosophila and mammalian cells. High-resolution genomic methods uncovered that pausing is not restricted to promoters, but occurs globally throughout gene-body regions, implying the existence of key-rate limiting steps in nascent RNA synthesis downstream of transcription initiation. Here, we outline the experimental breakthroughs that led to the discovery of pervasive transcriptional pausing, discuss its emerging roles and regulation, and highlight the importance of pausing in human development and disease.
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29
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Harlen KM, Churchman LS. Subgenic Pol II interactomes identify region-specific transcription elongation regulators. Mol Syst Biol 2017; 13:900. [PMID: 28043953 PMCID: PMC5293154 DOI: 10.15252/msb.20167279] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Transcription, RNA processing, and chromatin‐related factors all interact with RNA polymerase II (Pol II) to ensure proper timing and coordination of transcription and co‐transcriptional processes. Many transcription elongation regulators must function simultaneously to coordinate these processes, yet few strategies exist to explore the complement of factors regulating specific stages of transcription. To this end, we developed a strategy to purify Pol II elongation complexes from subgenic regions of a single gene, namely the 5′ and 3′ regions, using sequences in the nascent RNA. Applying this strategy to Saccharomyces cerevisiae, we determined the specific set of factors that interact with Pol II at precise stages during transcription. We identify many known region‐specific factors as well as determine unappreciated associations of regulatory factors during early and late stages of transcription. These data reveal a role for the transcription termination factor, Rai1, in regulating the early stages of transcription genome‐wide and support the role of Bye1 as a negative regulator of early elongation. We also demonstrate a role for the ubiquitin ligase, Bre1, in regulating Pol II dynamics during the latter stages of transcription. These data and our approach to analyze subgenic transcription elongation complexes will shed new light on the myriad factors that regulate the different stages of transcription and coordinate co‐transcriptional processes.
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Affiliation(s)
- Kevin M Harlen
- Department of Genetics, Harvard Medical School, Boston, MA, USA
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