1
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Callan-Sidat A, Zewdu E, Cavallaro M, Liu J, Hebenstreit D. N-terminal tagging of RNA Polymerase II shapes transcriptomes more than C-terminal alterations. iScience 2024; 27:109914. [PMID: 38799575 PMCID: PMC11126984 DOI: 10.1016/j.isci.2024.109914] [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: 04/20/2023] [Revised: 02/14/2024] [Accepted: 05/03/2024] [Indexed: 05/29/2024] Open
Abstract
RNA polymerase II (Pol II) has a C-terminal domain (CTD) that is unstructured, consisting of a large number of heptad repeats, and whose precise function remains unclear. Here, we investigate how altering the CTD's length and fusing it with protein tags affects transcriptional output on a genome-wide scale in mammalian cells at single-cell resolution. While transcription generally appears to occur in burst-like fashion, where RNA is predominantly made during short bursts of activity that are interspersed with periods of transcriptional silence, the CTD's role in shaping these dynamics seems gene-dependent; global patterns of bursting appear mostly robust to CTD alterations. Introducing protein tags with defined structures to the N terminus cause transcriptome-wide effects, however. We find the type of tag to dominate characteristics of the resulting transcriptomes. This is possibly due to Pol II-interacting factors, including non-coding RNAs, whose expression correlates with the tags. Proteins involved in liquid-liquid phase separation appear prominently.
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Affiliation(s)
- Adam Callan-Sidat
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Emmanuel Zewdu
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Massimo Cavallaro
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
- School of Computing and Mathematical Sciences, University of Leicester, Leicester LE1 7RH, UK
| | - Juntai Liu
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
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2
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Ling YH, Ye Z, Liang C, Yu C, Park G, Corden JL, Wu C. Disordered C-terminal domain drives spatiotemporal confinement of RNAPII to enhance search for chromatin targets. Nat Cell Biol 2024; 26:581-592. [PMID: 38548891 PMCID: PMC11210292 DOI: 10.1038/s41556-024-01382-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 02/21/2024] [Indexed: 04/09/2024]
Abstract
Efficient gene expression requires RNA polymerase II (RNAPII) to find chromatin targets precisely in space and time. How RNAPII manages this complex diffusive search in three-dimensional nuclear space remains largely unknown. The disordered carboxy-terminal domain (CTD) of RNAPII, which is essential for recruiting transcription-associated proteins, forms phase-separated droplets in vitro, hinting at a potential role in modulating RNAPII dynamics. In the present study, we use single-molecule tracking and spatiotemporal mapping in living yeast to show that the CTD is required for confining RNAPII diffusion within a subnuclear region enriched for active genes, but without apparent phase separation into condensates. Both Mediator and global chromatin organization are required for sustaining RNAPII confinement. Remarkably, truncating the CTD disrupts RNAPII spatial confinement, prolongs target search, diminishes chromatin binding, impairs pre-initiation complex formation and reduces transcription bursting. The present study illuminates the pivotal role of the CTD in driving spatiotemporal confinement of RNAPII for efficient gene expression.
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Affiliation(s)
- Yick Hin Ling
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Ziyang Ye
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Chloe Liang
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Chuofan Yu
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Giho Park
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Jeffry L Corden
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Carl Wu
- Department of Biology, Johns Hopkins University, Baltimore, MD, USA.
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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3
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Valyaeva AA, Sheval EV. Nonspecific Interactions in Transcription Regulation and Organization of Transcriptional Condensates. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:688-700. [PMID: 38831505 DOI: 10.1134/s0006297924040084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/19/2023] [Accepted: 11/20/2023] [Indexed: 06/05/2024]
Abstract
Eukaryotic cells are characterized by a high degree of compartmentalization of their internal contents, which ensures precise and controlled regulation of intracellular processes. During many processes, including different stages of transcription, dynamic membraneless compartments termed biomolecular condensates are formed. Transcription condensates contain various transcription factors and RNA polymerase and are formed by high- and low-specificity interactions between the proteins, DNA, and nearby RNA. This review discusses recent data demonstrating important role of nonspecific multivalent protein-protein and RNA-protein interactions in organization and regulation of transcription.
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Affiliation(s)
- Anna A Valyaeva
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119991, Russia.
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
- Department of Cell Biology and Histology, Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Eugene V Sheval
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
- Department of Cell Biology and Histology, Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
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4
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Lu F, Park BJ, Fujiwara R, Wilusz JE, Gilmour DS, Lehmann R, Lionnet T. Integrator-mediated clustering of poised RNA polymerase II synchronizes histone transcription. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.10.07.561364. [PMID: 37873455 PMCID: PMC10592978 DOI: 10.1101/2023.10.07.561364] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Numerous components of the transcription machinery, including RNA polymerase II (Pol II), accumulate in regions of high local concentration known as clusters, which are thought to facilitate transcription. Using the histone locus of Drosophila nurse cells as a model, we find that Pol II forms long-lived, transcriptionally poised clusters distinct from liquid droplets, which contain unbound and paused Pol II. Depletion of the Integrator complex endonuclease module, but not its phosphatase module or Pol II pausing factors disperses these Pol II clusters. Consequently, histone transcription fails to reach peak levels during S-phase and aberrantly continues throughout the cell cycle. We propose that Pol II clustering is a regulatory step occurring near promoters that limits rapid gene activation to defined times. One Sentence Summary Using the Drosophila histone locus as a model, we show that clustered RNA polymerase II is poised for synchronous activation.
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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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Ganser C, Staples MI, Dowell M, Frazer C, Dainis J, Sircaik S, Bennett RJ. Filamentation and biofilm formation are regulated by the phase-separation capacity of network transcription factors in Candida albicans. PLoS Pathog 2023; 19:e1011833. [PMID: 38091321 PMCID: PMC10718430 DOI: 10.1371/journal.ppat.1011833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 11/17/2023] [Indexed: 12/18/2023] Open
Abstract
The ability of the fungus Candida albicans to filament and form biofilms contributes to its burden as a leading cause of hospital-acquired infections. Biofilm development involves an interconnected transcriptional regulatory network (TRN) consisting of nine transcription factors (TFs) that bind both to their own regulatory regions and to those of the other network TFs. Here, we show that seven of the nine TFs in the C. albicans biofilm network contain prion-like domains (PrLDs) that have been linked to the ability to form phase-separated condensates. Construction of PrLD mutants in four biofilm TFs reveals that these domains are essential for filamentation and biofilm formation in C. albicans. Moreover, biofilm PrLDs promote the formation of phase-separated condensates in the nuclei of live cells, and PrLD mutations that abolish phase separation (such as the removal of aromatic residues) also prevent biofilm formation. Biofilm TF condensates can selectively recruit other TFs through PrLD-PrLD interactions and can co-recruit RNA polymerase II, implicating condensate formation in the assembly of active transcriptional complexes. Finally, we show that PrLD mutations that block the phase separation of biofilm TFs also prevent filamentation in an in vivo model of gastrointestinal colonization. Together, these studies associate transcriptional condensates with the regulation of filamentation and biofilm formation in C. albicans, and highlight how targeting of PrLD-PrLD interactions could prevent pathogenesis by this species.
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Affiliation(s)
- Collin Ganser
- Molecular Microbiology and Immunology Department, Brown University, Providence, Rhode Island, United States of America
| | - Mae I. Staples
- Molecular Microbiology and Immunology Department, Brown University, Providence, Rhode Island, United States of America
| | - Maureen Dowell
- Molecular Microbiology and Immunology Department, Brown University, Providence, Rhode Island, United States of America
| | - Corey Frazer
- Molecular Microbiology and Immunology Department, Brown University, Providence, Rhode Island, United States of America
| | - Joseph Dainis
- Molecular Microbiology and Immunology Department, Brown University, Providence, Rhode Island, United States of America
| | - Shabnam Sircaik
- Molecular Microbiology and Immunology Department, Brown University, Providence, Rhode Island, United States of America
| | - Richard J. Bennett
- Molecular Microbiology and Immunology Department, Brown University, Providence, Rhode Island, United States of America
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7
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Ling YH, Ye Z, Liang C, Yu C, Park G, Corden JL, Wu C. Disordered C-terminal domain drives spatiotemporal confinement of RNAPII to enhance search for chromatin targets. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.31.551302. [PMID: 37577667 PMCID: PMC10418089 DOI: 10.1101/2023.07.31.551302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Efficient gene expression requires RNA Polymerase II (RNAPII) to find chromatin targets precisely in space and time. How RNAPII manages this complex diffusive search in 3D nuclear space remains largely unknown. The disordered carboxy-terminal domain (CTD) of RNAPII, which is essential for recruiting transcription-associated proteins, forms phase-separated droplets in vitro, hinting at a potential role in modulating RNAPII dynamics. Here, we use single-molecule tracking and spatiotemporal mapping in living yeast to show that the CTD is required for confining RNAPII diffusion within a subnuclear region enriched for active genes, but without apparent phase separation into condensates. Both Mediator and global chromatin organization are required for sustaining RNAPII confinement. Remarkably, truncating the CTD disrupts RNAPII spatial confinement, prolongs target search, diminishes chromatin binding, impairs pre-initiation complex formation, and reduces transcription bursting. This study illuminates the pivotal role of the CTD in driving spatiotemporal confinement of RNAPII for efficient gene expression.
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Affiliation(s)
- Yick Hin Ling
- Department of Biology, Johns Hopkins University, Baltimore, USA
| | - Ziyang Ye
- Department of Biology, Johns Hopkins University, Baltimore, USA
| | - Chloe Liang
- Department of Biology, Johns Hopkins University, Baltimore, USA
| | - Chuofan Yu
- Department of Biology, Johns Hopkins University, Baltimore, USA
| | - Giho Park
- Department of Biology, Johns Hopkins University, Baltimore, USA
| | - Jeffry L Corden
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Carl Wu
- Department of Biology, Johns Hopkins University, Baltimore, USA
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, USA
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8
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Huang J, Ji X. Never a dull enzyme, RNA polymerase II. Transcription 2023; 14:49-67. [PMID: 37132022 PMCID: PMC10353340 DOI: 10.1080/21541264.2023.2208023] [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: 02/10/2023] [Revised: 04/18/2023] [Accepted: 04/21/2023] [Indexed: 05/04/2023] Open
Abstract
RNA polymerase II (Pol II) is composed of 12 subunits that collaborate to synthesize mRNA within the nucleus. Pol II is widely recognized as a passive holoenzyme, with the molecular functions of its subunits largely ignored. Recent studies employing auxin-inducible degron (AID) and multi-omics techniques have revealed that the functional diversity of Pol II is achieved through the differential contributions of its subunits to various transcriptional and post-transcriptional processes. By regulating these processes in a coordinated manner through its subunits, Pol II can optimize its activity for diverse biological functions. Here, we review recent progress in understanding Pol II subunits and their dysregulation in diseases, Pol II heterogeneity, Pol II clusters and the regulatory roles of RNA polymerases.
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Affiliation(s)
- Jie Huang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Xiong Ji
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
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9
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Dollinger R, Deng EB, Schultz J, Wu S, Deorio HR, Gilmour DS. Assessment of the roles of Spt5-nucleic acid contacts in promoter proximal pausing of RNA polymerase II. J Biol Chem 2023; 299:105106. [PMID: 37517697 PMCID: PMC10482750 DOI: 10.1016/j.jbc.2023.105106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 07/10/2023] [Accepted: 07/18/2023] [Indexed: 08/01/2023] Open
Abstract
Promoter proximal pausing of RNA polymerase II (Pol II) is a critical transcriptional regulatory mechanism in metazoans that requires the transcription factor DRB sensitivity-inducing factor (DSIF) and the inhibitory negative elongation factor (NELF). DSIF, composed of Spt4 and Spt5, establishes the pause by recruiting NELF to the elongation complex. However, the role of DSIF in pausing beyond NELF recruitment remains unclear. We used a highly purified in vitro system and Drosophila nuclear extract to investigate the role of DSIF in promoter proximal pausing. We identified two domains of Spt5, the KOW4 and NGN domains, that facilitate Pol II pausing. The KOW4 domain promotes pausing through its interaction with the nascent RNA while the NGN domain does so through a short helical motif that is in close proximity to the non-transcribed DNA template strand. Removal of this sequence in Drosophila has a male-specific dominant negative effect. The alpha-helical motif is also needed to support fly viability. We also show that the interaction between the Spt5 KOW1 domain and the upstream DNA helix is required for DSIF association with the Pol II elongation complex. Disruption of the KOW1-DNA interaction is dominant lethal in vivo. Finally, we show that the KOW2-3 domain of Spt5 mediates the recruitment of NELF to the elongation complex. In summary, our results reveal additional roles for DSIF in transcription regulation and identify specific domains important for facilitating Pol II pausing.
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Affiliation(s)
- Roberta Dollinger
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Eilene B Deng
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Josie Schultz
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Sharon Wu
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Haley R Deorio
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, USA; Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - David S Gilmour
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, USA.
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10
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Lushpinskaia IP, Flores-Solis D, Zweckstetter M. Structure and phase separation of the C-terminal domain of RNA polymerase II. Biol Chem 2023; 404:839-844. [PMID: 37331973 DOI: 10.1515/hsz-2023-0136] [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: 02/14/2023] [Accepted: 06/01/2023] [Indexed: 06/20/2023]
Abstract
The repetitive heptads in the C-terminal domain (CTD) of RPB1, the largest subunit of RNA Polymerase II (Pol II), play a critical role in the regulation of Pol II-based transcription. Recent findings on the structure of the CTD in the pre-initiation complex determined by cryo-EM and the novel phase separation properties of key transcription components offers an expanded mechanistic interpretation of the spatiotemporal distribution of Pol II during transcription. Current experimental evidence further suggests an exquisite balance between CTD's local structure and an array of multivalent interactions that drive phase separation of Pol II and thus shape its transcriptional activity.
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Affiliation(s)
- Irina P Lushpinskaia
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, D-35075 Göttingen, Germany
| | - David Flores-Solis
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, D-35075 Göttingen, Germany
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, D-35075 Göttingen, Germany
- Department of NMR-based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, D-37077 Göttingen, Germany
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11
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DeBerardine M, Booth GT, Versluis PP, Lis JT. The NELF pausing checkpoint mediates the functional divergence of Cdk9. Nat Commun 2023; 14:2762. [PMID: 37179384 PMCID: PMC10182999 DOI: 10.1038/s41467-023-38359-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
Promoter-proximal pausing by RNA Pol II is a rate-determining step in gene transcription that is hypothesized to be a prominent point at which regulatory factors act. The pausing factor NELF is known to induce and stabilize pausing, but not all kinds of pausing are NELF-mediated. Here, we find that NELF-depleted Drosophila melanogaster cells functionally recapitulate the NELF-independent pausing we previously observed in fission yeast (which lack NELF). Critically, only NELF-mediated pausing establishes a strict requirement for Cdk9 kinase activity for the release of paused Pol II into productive elongation. Upon inhibition of Cdk9, cells with NELF efficiently shutdown gene transcription, while in NELF-depleted cells, defective, non-productive transcription continues unabated. By introducing a strict checkpoint for Cdk9, the evolution of NELF was likely critical to enable increased regulation of Cdk9 in higher eukaryotes, as Cdk9 availability can be restricted to limit gene transcription without inducing wasteful, non-productive transcription.
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Affiliation(s)
- Michael DeBerardine
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Gregory T Booth
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Kanvas Biosciences, Monmouth Junction, NJ, USA
| | - Philip P Versluis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.
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12
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Boumpas P, Merabet S, Carnesecchi J. Integrating transcription and splicing into cell fate: Transcription factors on the block. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1752. [PMID: 35899407 DOI: 10.1002/wrna.1752] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 06/22/2022] [Accepted: 07/01/2022] [Indexed: 11/10/2022]
Abstract
Transcription factors (TFs) are present in all life forms and conserved across great evolutionary distances in eukaryotes. From yeast to complex multicellular organisms, they are pivotal players of cell fate decision by orchestrating gene expression at diverse molecular layers. Notably, TFs fine-tune gene expression by coordinating RNA fate at both the expression and splicing levels. They regulate alternative splicing, an essential mechanism for cell plasticity, allowing the production of many mRNA and protein isoforms in precise cell and tissue contexts. Despite this apparent role in splicing, how TFs integrate transcription and splicing to ultimately orchestrate diverse cell functions and cell fate decisions remains puzzling. We depict substantial studies in various model organisms underlining the key role of TFs in alternative splicing for promoting tissue-specific functions and cell fate. Furthermore, we emphasize recent advances describing the molecular link between the transcriptional and splicing activities of TFs. As TFs can bind both DNA and/or RNA to regulate transcription and splicing, we further discuss their flexibility and compatibility for DNA and RNA substrates. Finally, we propose several models integrating transcription and splicing activities of TFs in the coordination and diversification of cell and tissue identities. This article is categorized under: RNA Processing > Splicing Regulation/Alternative Splicing RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Processing > Splicing Mechanisms.
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Affiliation(s)
- Panagiotis Boumpas
- Institut de Génomique Fonctionnelle de Lyon, UMR5242, Ecole Normale Supérieure de Lyon, Centre National de la Recherche Scientifique, Université Claude Bernard-Lyon 1, Lyon, France
| | - Samir Merabet
- Institut de Génomique Fonctionnelle de Lyon, UMR5242, Ecole Normale Supérieure de Lyon, Centre National de la Recherche Scientifique, Université Claude Bernard-Lyon 1, Lyon, France
| | - Julie Carnesecchi
- Institut de Génomique Fonctionnelle de Lyon, UMR5242, Ecole Normale Supérieure de Lyon, Centre National de la Recherche Scientifique, Université Claude Bernard-Lyon 1, Lyon, France
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13
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Lyons H, Veettil RT, Pradhan P, Fornero C, De La Cruz N, Ito K, Eppert M, Roeder RG, Sabari BR. Functional partitioning of transcriptional regulators by patterned charge blocks. Cell 2023; 186:327-345.e28. [PMID: 36603581 PMCID: PMC9910284 DOI: 10.1016/j.cell.2022.12.013] [Citation(s) in RCA: 82] [Impact Index Per Article: 82.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 10/15/2022] [Accepted: 12/07/2022] [Indexed: 01/05/2023]
Abstract
Components of transcriptional machinery are selectively partitioned into specific condensates, often mediated by protein disorder, yet we know little about how this specificity is achieved. Here, we show that condensates composed of the intrinsically disordered region (IDR) of MED1 selectively partition RNA polymerase II together with its positive allosteric regulators while excluding negative regulators. This selective compartmentalization is sufficient to activate transcription and is required for gene activation during a cell-state transition. The IDRs of partitioned proteins are necessary and sufficient for selective compartmentalization and require alternating blocks of charged amino acids. Disrupting this charge pattern prevents partitioning, whereas adding the pattern to proteins promotes partitioning with functional consequences for gene activation. IDRs with similar patterned charge blocks show similar partitioning and function. These findings demonstrate that disorder-mediated interactions can selectively compartmentalize specific functionally related proteins from a complex mixture of biomolecules, leading to regulation of a biochemical pathway.
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Affiliation(s)
- Heankel Lyons
- Laboratory of Nuclear Organization, Cecil H. and Ida Green Center for Reproductive Biology Sciences, Division of Basic Research, Department of Obstetrics and Gynecology, Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Reshma T Veettil
- Laboratory of Nuclear Organization, Cecil H. and Ida Green Center for Reproductive Biology Sciences, Division of Basic Research, Department of Obstetrics and Gynecology, Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Prashant Pradhan
- Laboratory of Nuclear Organization, Cecil H. and Ida Green Center for Reproductive Biology Sciences, Division of Basic Research, Department of Obstetrics and Gynecology, Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Christy Fornero
- Laboratory of Nuclear Organization, Cecil H. and Ida Green Center for Reproductive Biology Sciences, Division of Basic Research, Department of Obstetrics and Gynecology, Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Nancy De La Cruz
- Laboratory of Nuclear Organization, Cecil H. and Ida Green Center for Reproductive Biology Sciences, Division of Basic Research, Department of Obstetrics and Gynecology, Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Keiichi Ito
- Laboratory of Biochemistry and Molecular Biology, the Rockefeller University, New York, NY 10065, USA
| | - Mikayla Eppert
- Laboratory of Nuclear Organization, Cecil H. and Ida Green Center for Reproductive Biology Sciences, Division of Basic Research, Department of Obstetrics and Gynecology, Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Robert G Roeder
- Laboratory of Biochemistry and Molecular Biology, the Rockefeller University, New York, NY 10065, USA
| | - Benjamin R Sabari
- Laboratory of Nuclear Organization, Cecil H. and Ida Green Center for Reproductive Biology Sciences, Division of Basic Research, Department of Obstetrics and Gynecology, Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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14
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Kuznetsova K, Chabot NM, Ugolini M, Wu E, Lalit M, Oda H, Sato Y, Kimura H, Jug F, Vastenhouw NL. Nanog organizes transcription bodies. Curr Biol 2023; 33:164-173.e5. [PMID: 36476751 DOI: 10.1016/j.cub.2022.11.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 09/21/2022] [Accepted: 11/07/2022] [Indexed: 12/12/2022]
Abstract
The localization of transcriptional activity in specialized transcription bodies is a hallmark of gene expression in eukaryotic cells.1-3 How proteins of the transcriptional machinery come together to form such bodies, however, is unclear. Here, we take advantage of two large, isolated, and long-lived transcription bodies that reproducibly form during early zebrafish embryogenesis to characterize the dynamics of transcription body formation. Once formed, these transcription bodies are enriched for initiating and elongating RNA polymerase II, as well as the transcription factors Nanog and Sox19b. Analyzing the events leading up to transcription, we find that Nanog and Sox19b cluster prior to transcription. The clustering of transcription factors is sequential; Nanog clusters first, and this is required for the clustering of Sox19b and the initiation of transcription. Mutant analysis revealed that both the DNA-binding domain as well as one of the two intrinsically disordered regions of Nanog are required to organize the two bodies of transcriptional activity. Taken together, our data suggest that the clustering of transcription factors dictates the formation of transcription bodies.
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Affiliation(s)
- Ksenia Kuznetsova
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Noémie M Chabot
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany; Center for Integrative Genomics, University of Lausanne, Quartier Sorge, 1015 Lausanne, Switzerland
| | - Martino Ugolini
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany; Center for Integrative Genomics, University of Lausanne, Quartier Sorge, 1015 Lausanne, Switzerland
| | - Edlyn Wu
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany; Center for Integrative Genomics, University of Lausanne, Quartier Sorge, 1015 Lausanne, Switzerland
| | - Manan Lalit
- Center for Systems Biology Dresden, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Haruka Oda
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Yuko Sato
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Hiroshi Kimura
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan
| | - Florian Jug
- Center for Systems Biology Dresden, Pfotenhauerstrasse 108, 01307 Dresden, Germany; Fondazione Human Technopole, Viale Rita Levi-Montalcini 1, Area MIND, 20157 Milano, Italy
| | - Nadine L Vastenhouw
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany; Center for Integrative Genomics, University of Lausanne, Quartier Sorge, 1015 Lausanne, Switzerland.
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15
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Lambert É, Puwakdandawa K, Tao YF, Robert F. From structure to molecular condensates: emerging mechanisms for Mediator function. FEBS J 2023; 290:286-309. [PMID: 34698446 DOI: 10.1111/febs.16250] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 10/15/2021] [Accepted: 10/25/2021] [Indexed: 02/05/2023]
Abstract
Mediator is a large modular protein assembly whose function as a coactivator of transcription is conserved in all eukaryotes. The Mediator complex can integrate and relay signals from gene-specific activators bound at enhancers to activate the general transcription machinery located at promoters. It has thus been described as a bridge between these elements during initiation of transcription. Here, we review recent studies on Mediator relating to its structure, gene specificity and general requirement, roles in chromatin architecture as well as novel concepts involving phase separation and transcriptional bursting. We revisit the mechanism of action of Mediator and ultimately put forward models for its mode of action in gene activation.
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Affiliation(s)
- Élie Lambert
- Institut de recherches cliniques de Montréal, Canada
| | | | - Yi Fei Tao
- Institut de recherches cliniques de Montréal, Canada
| | - François Robert
- Institut de recherches cliniques de Montréal, Canada.,Département de Médecine, Faculté de Médecine, Université de Montréal, Canada
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16
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Chowdhary S, Kainth AS, Paracha S, Gross DS, Pincus D. Inducible transcriptional condensates drive 3D genome reorganization in the heat shock response. Mol Cell 2022; 82:4386-4399.e7. [PMID: 36327976 PMCID: PMC9701134 DOI: 10.1016/j.molcel.2022.10.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 08/28/2022] [Accepted: 10/10/2022] [Indexed: 11/12/2022]
Abstract
Mammalian developmental and disease-associated genes concentrate large quantities of the transcriptional machinery by forming membrane-less compartments known as transcriptional condensates. However, it is unknown whether these structures are evolutionarily conserved or involved in 3D genome reorganization. Here, we identify inducible transcriptional condensates in the yeast heat shock response (HSR). HSR condensates are biophysically dynamic spatiotemporal clusters of the sequence-specific transcription factor heat shock factor 1 (Hsf1) with Mediator and RNA Pol II. Uniquely, HSR condensates drive the coalescence of multiple Hsf1 target genes, even those located on different chromosomes. Binding of the chaperone Hsp70 to a site on Hsf1 represses clustering, whereas an intrinsically disordered region on Hsf1 promotes condensate formation and intergenic interactions. Mutation of both Hsf1 determinants reprograms HSR condensates to become constitutively active without intergenic coalescence, which comes at a fitness cost. These results suggest that transcriptional condensates are ancient and flexible compartments of eukaryotic gene control.
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Affiliation(s)
- Surabhi Chowdhary
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Amoldeep S Kainth
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA
| | - Sarah Paracha
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - David S Gross
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA.
| | - David Pincus
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA; Center for Physics of Evolving Systems, University of Chicago, Chicago, IL 60637, USA.
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17
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Li Y, Huang J, Zhu J, Bao L, Wang H, Jiang Y, Tian K, Wang R, Zheng H, Duan W, Lai W, Yi X, Zhu Y, Guo T, Ji X. Targeted protein degradation reveals RNA Pol II heterogeneity and functional diversity. Mol Cell 2022; 82:3943-3959.e11. [PMID: 36113479 DOI: 10.1016/j.molcel.2022.08.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 07/14/2022] [Accepted: 08/18/2022] [Indexed: 10/14/2022]
Abstract
RNA polymerase II (RNA Pol II) subunits are thought to be involved in various transcription-associated processes, but it is unclear whether they play different regulatory roles in modulating gene expression. Here, we performed nascent and mature transcript sequencing after the acute degradation of 12 mammalian RNA Pol II subunits and profiled their genomic binding sites and protein interactomes to dissect their molecular functions. We found that RNA Pol II subunits contribute differently to RNA Pol II cellular localization and transcription processes and preferentially regulate RNA processing (such as RNA splicing and 3' end maturation). Genes sensitive to the depletion of different RNA Pol II subunits tend to be involved in diverse biological functions and show different RNA half-lives. Sequences, associated protein factors, and RNA structures are correlated with RNA Pol II subunit-mediated differential gene expression. These findings collectively suggest that the heterogeneity of RNA Pol II and different genes appear to depend on some of the subunits.
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Affiliation(s)
- Yuanjun Li
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Jie Huang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Junyi Zhu
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Lijun Bao
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Hui Wang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yongpeng Jiang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Kai Tian
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Rui Wang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Haonan Zheng
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - WenJia Duan
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Weifeng Lai
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Xiao Yi
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
| | - Yi Zhu
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
| | - Tiannan Guo
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
| | - Xiong Ji
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China.
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18
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Palumbo RJ, McKean N, Leatherman E, Namitz KEW, Connell L, Wolfe A, Moody K, Gostinčar C, Gunde-Cimerman N, Bah A, Hanes SD. Coevolution of the Ess1-CTD axis in polar fungi suggests a role for phase separation in cold tolerance. SCIENCE ADVANCES 2022; 8:eabq3235. [PMID: 36070379 PMCID: PMC9451162 DOI: 10.1126/sciadv.abq3235] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 07/21/2022] [Indexed: 06/14/2023]
Abstract
Most of the world's biodiversity lives in cold (-2° to 4°C) and hypersaline environments. To understand how cells adapt to such conditions, we isolated two key components of the transcription machinery from fungal species that live in extreme polar environments: the Ess1 prolyl isomerase and its target, the carboxy-terminal domain (CTD) of RNA polymerase II. Polar Ess1 enzymes are conserved and functional in the model yeast, Saccharomyces cerevisiae. By contrast, polar CTDs diverge from the consensus (YSPTSPS)26 and are not fully functional in S. cerevisiae. These CTDs retain the critical Ess1 Ser-Pro target motifs, but substitutions at Y1, T4, and S7 profoundly affected their ability to undergo phase separation in vitro and localize in vivo. We propose that environmentally tuned phase separation by the CTD and other intrinsically disordered regions plays an adaptive role in cold tolerance by concentrating enzymes and substrates to overcome energetic barriers to metabolic activity.
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Affiliation(s)
- Ryan J. Palumbo
- Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY 13210, USA
| | - Nathan McKean
- Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY 13210, USA
| | - Erinn Leatherman
- Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY 13210, USA
| | - Kevin E. W. Namitz
- Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY 13210, USA
| | - Laurie Connell
- School of Marine Sciences and Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME 04469, USA
| | - Aaron Wolfe
- Ichor Life Sciences Inc., 2651 US Route 11, LaFayette, NY 13084, USA
- Lewis School of Health Sciences, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699, USA
- The BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Kelsey Moody
- Ichor Life Sciences Inc., 2651 US Route 11, LaFayette, NY 13084, USA
- Lewis School of Health Sciences, Clarkson University, 8 Clarkson Avenue, Potsdam, NY 13699, USA
- The BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Cene Gostinčar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
| | - Nina Gunde-Cimerman
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
| | - Alaji Bah
- Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY 13210, USA
| | - Steven D. Hanes
- Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY 13210, USA
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19
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Gildea MA, Dwyer ZW, Pleiss JA. Transcript-specific determinants of pre-mRNA splicing revealed through in vivo kinetic analyses of the 1 st and 2 nd chemical steps. Mol Cell 2022; 82:2967-2981.e6. [PMID: 35830855 PMCID: PMC9391291 DOI: 10.1016/j.molcel.2022.06.020] [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: 10/13/2020] [Revised: 01/31/2022] [Accepted: 06/12/2022] [Indexed: 10/17/2022]
Abstract
We generate high-precision measurements of the in vivo rates of both chemical steps of pre-mRNA splicing across the genome-wide complement of substrates in yeast by coupling metabolic labeling, multiplexed primer-extension sequencing, and kinetic modeling. We demonstrate that the rates of intron removal vary widely, splice-site sequences are primary determinants of 1st step but have little apparent impact on 2nd step rates, and the 2nd step is generally faster than the 1st step. Ribosomal protein genes (RPGs) are spliced faster than non-RPGs at each step, and RPGs share evolutionarily conserved properties that may contribute to their faster splicing. A genetic variant defective in the 1st step of the pathway reveals a genome-wide defect in the 1st step but an unexpected, transcript-specific change in the 2nd step. Our work demonstrates that extended co-transcriptional association is an important determinant of splicing rate, a conclusion at odds with recent claims of ultra-fast splicing.
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Affiliation(s)
- Michael A Gildea
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
| | - Zachary W Dwyer
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
| | - Jeffrey A Pleiss
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA.
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20
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Wang Z, Deng W. Dynamic transcription regulation at the single-molecule level. Dev Biol 2021; 482:67-81. [PMID: 34896367 DOI: 10.1016/j.ydbio.2021.11.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 11/14/2021] [Accepted: 11/15/2021] [Indexed: 02/07/2023]
Abstract
Cell fate changes during development, differentiation, and reprogramming are largely controlled at the transcription level. The DNA-binding transcription factors (TFs) often act in a combinatorial fashion to alter chromatin states and drive cell type-specific gene expression. Recent advances in fluorescent microscopy technologies have enabled direct visualization of biomolecules involved in the process of transcription and its regulatory events at the single-molecule level in living cells. Remarkably, imaging and tracking individual TF molecules at high temporal and spatial resolution revealed that they are highly dynamic in searching and binding cognate targets, rather than static and binding constantly. In combination with investigation using techniques from biochemistry, structure biology, genetics, and genomics, a more well-rounded view of transcription regulation is emerging. In this review, we briefly cover the technical aspects of live-cell single-molecule imaging and focus on the biological relevance and interpretation of the single-molecule dynamic features of transcription regulatory events observed in the native chromatin environment of living eukaryotic cells. We also discuss how these dynamic features might shed light on mechanistic understanding of transcription regulation.
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Affiliation(s)
- Zuhui Wang
- Biomedical Pioneering Innovation Center (BIOPIC), Peking University, Beijing, 100871, China; Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Wulan Deng
- Biomedical Pioneering Innovation Center (BIOPIC), Peking University, Beijing, 100871, China; Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China; Beijing Advanced Innovation Center for Genomics (ICG), Peking University, Beijing, 100871, China; Peking-Tsinghua Center for Life Sciences (CLS), Peking University, Beijing, 100871, China; School of Life Sciences, Peking University, Beijing, 100871, China.
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21
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Murthy AC, Tang WS, Jovic N, Janke AM, Seo DH, Perdikari TM, Mittal J, Fawzi NL. Molecular interactions contributing to FUS SYGQ LC-RGG phase separation and co-partitioning with RNA polymerase II heptads. Nat Struct Mol Biol 2021; 28:923-935. [PMID: 34759379 PMCID: PMC8654040 DOI: 10.1038/s41594-021-00677-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 09/28/2021] [Indexed: 01/23/2023]
Abstract
The RNA-binding protein FUS (Fused in Sarcoma) mediates phase separation in biomolecular condensates and functions in transcription by clustering with RNA polymerase II. Specific contact residues and interaction modes formed by FUS and the C-terminal heptad repeats of RNA polymerase II (CTD) have been suggested but not probed directly. Here we show how RGG domains contribute to phase separation with the FUS N-terminal low-complexity domain (SYGQ LC) and RNA polymerase II CTD. Using NMR spectroscopy and molecular simulations, we demonstrate that many residue types, not solely arginine-tyrosine pairs, form condensed-phase contacts via several interaction modes including, but not only sp2-π and cation-π interactions. In phases also containing RNA polymerase II CTD, many residue types form contacts, including both cation-π and hydrogen-bonding interactions formed by the conserved human CTD lysines. Hence, our data suggest a surprisingly broad array of residue types and modes explain co-phase separation of FUS and RNA polymerase II.
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Affiliation(s)
- Anastasia C Murthy
- Graduate Program in Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Wai Shing Tang
- Graduate Program in Physics, Brown University, Providence, RI, USA
| | - Nina Jovic
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
| | - Abigail M Janke
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Da Hee Seo
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | | | - Jeetain Mittal
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA.
| | - Nicolas L Fawzi
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA.
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22
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Abstract
To predict transcription, one needs a mechanistic understanding of how the numerous required transcription factors (TFs) explore the nuclear space to find their target genes, assemble, cooperate, and compete with one another. Advances in fluorescence microscopy have made it possible to visualize real-time TF dynamics in living cells, leading to two intriguing observations: first, most TFs contact chromatin only transiently; and second, TFs can assemble into clusters through their intrinsically disordered regions. These findings suggest that highly dynamic events and spatially structured nuclear microenvironments might play key roles in transcription regulation that are not yet fully understood. The emerging model is that while some promoters directly convert TF-binding events into on/off cycles of transcription, many others apply complex regulatory layers that ultimately lead to diverse phenotypic outputs. Cracking this kinetic code is an ongoing and challenging task that is made possible by combining innovative imaging approaches with biophysical models.
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Affiliation(s)
- Feiyue Lu
- Institute for Systems Genetics and Cell Biology Department, NYU School of Medicine, New York, New York 10016, USA
| | - Timothée Lionnet
- Institute for Systems Genetics and Cell Biology Department, NYU School of Medicine, New York, New York 10016, USA
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23
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Lin Y, Fang X. Phase separation in RNA biology. J Genet Genomics 2021; 48:872-880. [PMID: 34371110 DOI: 10.1016/j.jgg.2021.07.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 07/19/2021] [Accepted: 07/20/2021] [Indexed: 11/23/2022]
Abstract
The formation of biomolecular condensates via liquid-liquid phase separation (LLPS) is an advantageous strategy for cells to organize subcellular compartments for diverse functions. The involvement of LLPS is more widespread and overrepresented in RNA-related biological processes. This is in part because that RNAs are intrinsically multivalent macromolecules, and the presence of RNAs affects the formation, dissolution, and biophysical properties of biomolecular condensates formed by LLPS. Emerging studies have illustrated how LLPS participates in RNA transcription, splicing, processing, quality control, translation, and function. The interconnected regulation between LLPS and RNAs ensures tight control of RNA-related cellular functions.
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Affiliation(s)
- Yi Lin
- School of Life Sciences, Tsinghua University, Beijing 100084, China.
| | - Xiaofeng Fang
- School of Life Sciences, Tsinghua University, Beijing 100084, China.
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24
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Zhou Y, Zhu L, Sun Y, Zhang H, Wang J, Qin W, He W, Zhou L, Li Q, Zhao R, Luo K, Tang C, Zhang C, Liu S. Localization of RNA Pol II CTD (S5) and Transcriptome Analysis of Testis in Diploid and Tetraploid Hybrids of Red Crucian Carp (♀) × Common Carp (♂). Front Genet 2021; 12:717871. [PMID: 34567072 PMCID: PMC8458772 DOI: 10.3389/fgene.2021.717871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/03/2021] [Indexed: 11/15/2022] Open
Abstract
Polyploidy occurs naturally in fish; however, the appearance of these species is an occasional and gradual process, which makes it difficult to trace the changes in phenotypes, genotypes, and regulation of gene expression. The allotetraploid hybrids (4nAT) of red crucian carp (RCC; ♀) × common carp (CC; ♂) generated from interspecies crossing are a good model to investigate the initial changes after allopolyploidization. In the present study, we focused on the changes in the active sites of the testicular transcriptome of the allotetraploid by localization of RNA Pol II CTD YSPTSPS (phospho S5) using immunofluorescence and RNA-seq data via bioinformatic analysis. The results showed that there was no significant difference in signal counts of the RNA Pol II CTD (S5) between the different types of fish at the same stages, including RCC, CC, 2nF1, and 4nAT, which means that the number of transcriptionally active sites on germ cell chromosomes was not affected by the increase in chromosome number. Similarly, RNA-seq analysis indicated that in the levels of chromosomes and 10-kb regions in the genome, there were no significant changes in the highly active sites in RCC, 2nF1, and 4nAT. These findings suggest that at the beginning of tetraploid origin, the active transcriptome site of 4nAT in the testis was conserved in the regions of the genome compared to that in RCC and 2nF1. In conclusion, 4nAT shared a similar gene expression model in the regions of the genome with RCC and 2nF1 with significantly different expression levels.
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Affiliation(s)
- Yi Zhou
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - La Zhu
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Yu Sun
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Hui Zhang
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Jiaojiao Wang
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Weilin Qin
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Wangchao He
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Luojing Zhou
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Qi Li
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Rurong Zhao
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Kaikun Luo
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Chenchen Tang
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Chun Zhang
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
| | - Shaojun Liu
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education Ministry, Hunan Normal University, Changsha, China
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25
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Intrinsically disordered protein regions and phase separation: sequence determinants of assembly or lack thereof. Emerg Top Life Sci 2021; 4:307-329. [PMID: 33078839 DOI: 10.1042/etls20190164] [Citation(s) in RCA: 130] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/23/2020] [Accepted: 09/28/2020] [Indexed: 02/07/2023]
Abstract
Intrinsically disordered protein regions (IDRs) - regions that do not fold into a fixed three-dimensional structure but instead exist in a heterogeneous ensemble of conformations - have recently entered mainstream cell biology in the context of liquid-liquid phase separation (LLPS). IDRs are frequently found to be enriched in phase-separated compartments. Due to this observation, the presence of an IDR in a protein is frequently assumed to be diagnostic of its ability to phase separate. In this review, we clarify the role of IDRs in biological assembly and explore the physical principles through which amino acids can confer the attractive molecular interactions that underlie phase separation. While some disordered regions will robustly drive phase separation, many others will not. We emphasize that rather than 'disorder' driving phase separation, multivalency drives phase separation. As such, whether or not a disordered region is capable of driving phase separation will depend on the physical chemistry encoded within its amino acid sequence. Consequently, an in-depth understanding of that physical chemistry is a prerequisite to make informed inferences on how and why an IDR may be involved in phase separation or, more generally, in protein-mediated intermolecular interactions.
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26
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Feric M, Misteli T. Phase separation in genome organization across evolution. Trends Cell Biol 2021; 31:671-685. [PMID: 33771451 PMCID: PMC8286288 DOI: 10.1016/j.tcb.2021.03.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/17/2021] [Accepted: 03/01/2021] [Indexed: 02/06/2023]
Abstract
Phase separation is emerging as a paradigm to explain the self-assembly and organization of membraneless bodies in the cell. Recent advances show that this principle also extends to nucleoprotein complexes, including DNA-based structures. We discuss here recent observations on the role of phase separation in genome organization across the evolutionary spectrum from bacteria to mammals. These findings suggest that molecular interactions amongst DNA-binding proteins evolved to form a variety of biomolecular condensates with distinct material properties that affect genome organization and function. We suggest that phase separation contributes to genome organization across evolution and that the resulting phase behavior of genomes may underlie regulatory mechanisms and disease.
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Affiliation(s)
- Marina Feric
- National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, USA; National Institute of General Medical Sciences, NIH, Bethesda, MD, USA.
| | - Tom Misteli
- National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, USA.
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27
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Venkat Ramani MK, Yang W, Irani S, Zhang Y. Simplicity is the Ultimate Sophistication-Crosstalk of Post-translational Modifications on the RNA Polymerase II. J Mol Biol 2021; 433:166912. [PMID: 33676925 PMCID: PMC8184622 DOI: 10.1016/j.jmb.2021.166912] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/23/2021] [Accepted: 02/26/2021] [Indexed: 12/19/2022]
Abstract
The highly conserved C-terminal domain (CTD) of the largest subunit of RNA polymerase II comprises a consensus heptad (Y1S2P3T4S5P6S7) repeated multiple times. Despite the simplicity of its sequence, the essential CTD domain orchestrates eukaryotic transcription and co-transcriptional processes, including transcription initiation, elongation, and termination, and mRNA processing. These distinct facets of the transcription cycle rely on specific post-translational modifications (PTM) of the CTD, in which five out of the seven residues in the heptad repeat are subject to phosphorylation. A hypothesis termed the "CTD code" has been proposed in which these PTMs and their combinations generate a sophisticated landscape for spatiotemporal recruitment of transcription regulators to Pol II. In this review, we summarize the recent experimental evidence understanding the biological role of the CTD, implicating a context-dependent theme that significantly enhances the ability of accurate transcription by RNA polymerase II. Furthermore, feedback communication between the CTD and histone modifications coordinates chromatin states with RNA polymerase II-mediated transcription, ensuring the effective and accurate conversion of information into cellular responses.
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Affiliation(s)
| | - Wanjie Yang
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, United States
| | - Seema Irani
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, United States
| | - Yan Zhang
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, United States; The Institute for Cellular and Molecular Biology. University of Texas at Austin, Austin, TX 78712, United States.
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28
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Dieci G. Removing quote marks from the RNA polymerase II CTD 'code'. Biosystems 2021; 207:104468. [PMID: 34216714 DOI: 10.1016/j.biosystems.2021.104468] [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] [Received: 05/11/2021] [Revised: 06/24/2021] [Accepted: 06/27/2021] [Indexed: 11/27/2022]
Abstract
In eukaryotes, RNA polymerase II (Pol II) is responsible for the synthesis of all mRNAs and myriads of short and long untranslated RNAs, whose fabrication involves close spatiotemporal coordination between transcription, RNA processing and chromatin modification. Crucial for such a coordination is an unusual C-terminal domain (CTD) of the Pol II largest subunit, made of tandem repetitions (26 in yeast, 52 in chordates) of the heptapeptide with the consensus sequence YSPTSPS. Although largely unstructured and with poor sequence content, the Pol II CTD derives its extraordinary functional versatility from the fact that each amino acid in the heptapeptide can be posttranslationally modified, and that different combinations of CTD covalent marks are specifically recognized by different protein binding partners. These features have led to propose the existence of a Pol II CTD code, but this expression is generally used by authors with some caution, revealed by the frequent use of quote marks for the word 'code'. Based on the theoretical framework of code biology, it is argued here that the Pol II CTD modification system meets the requirements of a true organic code, where different CTD modification states represent organic signs whose organic meanings are biological reactions contributing to the many facets of RNA biogenesis in coordination with RNA synthesis by Pol II. Importantly, the Pol II CTD code is instantiated by adaptor proteins possessing at least two distinct domains, one of which devoted to specific recognition of CTD modification profiles. Furthermore, code rules can be altered by experimental interchange of CTD recognition domains of different adaptor proteins, a fact arguing in favor of the arbitrariness, and thus bona fide character, of the Pol II CTD code. Since the growing family of CTD adaptors includes RNA binding proteins and histone modification complexes, the Pol II CTD code is by its nature integrated with other organic codes, in particular the splicing code and the histone code. These issues will be discussed taking into account fascinating developments in Pol II CTD research, like the discovery of novel modifications at non-consensus sites, the recently recognized CTD physicochemical properties favoring liquid-liquid phase separation, and the discovery that the Pol II CTD, originated before the divergence of most extant eukaryotic taxa, has expanded and diversified with developmental complexity in animals and plants.
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Affiliation(s)
- Giorgio Dieci
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 23/A, 43124, Parma, Italy.
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29
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Portz B, Shorter J. Biochemical Timekeeping Via Reentrant Phase Transitions. J Mol Biol 2021; 433:166794. [PMID: 33387533 PMCID: PMC8154630 DOI: 10.1016/j.jmb.2020.166794] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 12/03/2020] [Accepted: 12/23/2020] [Indexed: 02/06/2023]
Abstract
Appreciation for the role of liquid-liquid phase separation in the functional organization of cellular matter has exploded in recent years. More recently there has been a growing effort to understand the principles of heterotypic phase separation, the demixing of multiple proteins and nucleic acids into a single functional condensate. A phase transition is termed reentrant if it involves the transformation of a system from one state into a macroscopically similar or identical state via at least two phase transitions elicited by variation of a single parameter. Reentrant liquid-liquid phase separation can occur when the condensation of one species is tuned by another. Reentrant phase transitions have been modeled in vitro using protein and RNA mixtures. These biochemical studies reveal two features of reentrant phase separation that are likely important to functional cellular condensates: (1) the ability to generate condensates with layered functional topologies, and (2) the ability to generate condensates whose composition and duration are self-limiting to enable a form of biochemical timekeeping. We relate these biochemical studies to potential cellular examples and discuss how layered topologies and self-regulation may impact key biological processes.
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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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30
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Sabari BR. Biomolecular Condensates and Gene Activation in Development and Disease. Dev Cell 2021; 55:84-96. [PMID: 33049213 DOI: 10.1016/j.devcel.2020.09.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/18/2020] [Accepted: 09/04/2020] [Indexed: 01/04/2023]
Abstract
Activating the right gene at the right time and place is essential for development. Emerging evidence suggests that this process is regulated by the mesoscale compartmentalization of the gene-control machinery, RNA polymerase II and its cofactors, within biomolecular condensates. Coupling gene activity to the reversible and dynamic process of condensate formation is proposed to enable the robust and precise changes in gene-regulatory programs during signaling and development. The macromolecular features that enable condensates and the regulatory pathways that control them are dysregulated in disease, highlighting their importance for normal physiology. In this review, we will discuss the role of condensates in gene activation; the multivalent features of protein, RNA, and DNA that enable reversible condensate formation; and how these processes are utilized in normal and disease biology. Understanding the regulation of condensates promises to provide novel insights into how organization of the gene-control machinery regulates development and disease.
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Affiliation(s)
- Benjamin R Sabari
- Laboratory of Nuclear Organization, Cecil H. and Ida Green Center for Reproductive Biology Sciences, Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Molecular Biology, Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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31
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Sawicka A, Villamil G, Lidschreiber M, Darzacq X, Dugast-Darzacq C, Schwalb B, Cramer P. Transcription activation depends on the length of the RNA polymerase II C-terminal domain. EMBO J 2021; 40:e107015. [PMID: 33555055 PMCID: PMC8090853 DOI: 10.15252/embj.2020107015] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/04/2021] [Accepted: 01/13/2021] [Indexed: 01/02/2023] Open
Abstract
Eukaryotic RNA polymerase II (Pol II) contains a tail‐like, intrinsically disordered carboxy‐terminal domain (CTD) comprised of heptad‐repeats, that functions in coordination of the transcription cycle and in coupling transcription to co‐transcriptional processes. The CTD repeat number varies between species and generally increases with genome size, but the reasons for this are unclear. Here, we show that shortening the CTD in human cells to half of its length does not generally change pre‐mRNA synthesis or processing in cells. However, CTD shortening decreases the duration of promoter‐proximal Pol II pausing, alters transcription of putative enhancer elements, and delays transcription activation after stimulation of the MAP kinase pathway. We suggest that a long CTD is required for efficient enhancer‐dependent recruitment of Pol II to target genes for their rapid activation.
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Affiliation(s)
- Anna Sawicka
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Gabriel Villamil
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Michael Lidschreiber
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Xavier Darzacq
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.,CIRM Center of Excellence, University of California, Berkeley, CA, USA
| | - Claire Dugast-Darzacq
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.,CIRM Center of Excellence, University of California, Berkeley, CA, USA
| | - Björn Schwalb
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
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32
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Nosella ML, Forman-Kay JD. Phosphorylation-dependent regulation of messenger RNA transcription, processing and translation within biomolecular condensates. Curr Opin Cell Biol 2021; 69:30-40. [PMID: 33450720 DOI: 10.1016/j.ceb.2020.12.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 12/09/2020] [Accepted: 12/13/2020] [Indexed: 12/29/2022]
Abstract
Regulation of messenger RNA (mRNA) transcription, processing and translation occurs in the context of biomolecular condensates. How the physical properties of condensates connect with their biological regulatory functions is an ongoing area of interest, particularly for RNA metabolic pathways. Phosphorylation has emerged as an important mechanism for regulating protein phase separation propensities and localization patterns into different condensates, affecting compositions and dynamics. Key factors in transcription, mRNA processing and translation exhibit such phosphorylation-dependent changes in their roles within condensates, including their catalytic activities. Phosphorylation is increasingly understood to regulate the exchange of proteins through functionally linked condensates to fulfil their mRNA metabolic functions.
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Affiliation(s)
- Michael L Nosella
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, M5G 0A4, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Julie D Forman-Kay
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, ON, M5G 0A4, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, M5S 1A8, Canada.
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33
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Lionnet T, Wu C. Single-molecule tracking of transcription protein dynamics in living cells: seeing is believing, but what are we seeing? Curr Opin Genet Dev 2021; 67:94-102. [PMID: 33422933 DOI: 10.1016/j.gde.2020.12.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/24/2020] [Accepted: 12/01/2020] [Indexed: 12/20/2022]
Abstract
A universe of transcription factors (TFs), cofactors, as well as chromatin remodeling and modifying enzymes combine or compete on chromatin to control transcription. Measuring quantitatively how these proteins dynamically interact is required in order to formulate models with predictive ability to elucidate transcription control mechanisms. Single molecule tracking (SMT) provides a powerful tool towards this goal: it is a fluorescence microscopy approach that measures the location and mobility of individual TF molecules, as well as their rates of association with and dissociation from chromatin in the physiological context of the living cell. Here we review SMT principles, and discuss key TF properties uncovered by live-cell SMT, such as fast turnover (seconds), and formation of clusters that locally increase activity.
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Affiliation(s)
- Timothée Lionnet
- Institute for Systems Genetics, Science Building 807, 435 E 30th Street, NYC, NY 10016, USA.
| | - Carl Wu
- Johns Hopkins University, Department of Biology, 3400 N Charles St, Baltimore, MD 21218, USA.
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34
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Cassart C, Yague-Sanz C, Bauer F, Ponsard P, Stubbe FX, Migeot V, Wery M, Morillon A, Palladino F, Robert V, Hermand D. RNA polymerase II CTD S2P is dispensable for embryogenesis but mediates exit from developmental diapause in C. elegans. SCIENCE ADVANCES 2020; 6:6/50/eabc1450. [PMID: 33298437 PMCID: PMC7725455 DOI: 10.1126/sciadv.abc1450] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 10/21/2020] [Indexed: 06/12/2023]
Abstract
Serine 2 phosphorylation (S2P) within the CTD of RNA polymerase II is considered a Cdk9/Cdk12-dependent mark required for 3'-end processing. However, the relevance of CTD S2P in metazoan development is unknown. We show that cdk-12 lesions or a full-length CTD S2A substitution results in an identical phenotype in Caenorhabditis elegans Embryogenesis occurs in the complete absence of S2P, but the hatched larvae arrest development, mimicking the diapause induced when hatching occurs in the absence of food. Genome-wide analyses indicate that when CTD S2P is inhibited, only a subset of growth-related genes is not properly expressed. These genes correspond to SL2 trans-spliced mRNAs located in position 2 and over within operons. We show that CDK-12 is required for maximal occupancy of cleavage stimulatory factor necessary for SL2 trans-splicing. We propose that CTD S2P functions as a gene-specific signaling mark ensuring the nutritional control of the C. elegans developmental program.
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Affiliation(s)
- C Cassart
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur 5000 Belgium
| | - C Yague-Sanz
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur 5000 Belgium
| | - F Bauer
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur 5000 Belgium
| | - P Ponsard
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur 5000 Belgium
| | - F X Stubbe
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur 5000 Belgium
| | - V Migeot
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur 5000 Belgium
| | - M Wery
- ncRNA, epigenetic and genome fluidity, Institut Curie, PSL Research University, CNRS UMR 3244, Université Pierre et Marie Curie, Paris, France
| | - A Morillon
- ncRNA, epigenetic and genome fluidity, Institut Curie, PSL Research University, CNRS UMR 3244, Université Pierre et Marie Curie, Paris, France
| | - F Palladino
- Laboratory of Biology and Modeling of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, Université de Lyon, Lyon, France
| | - V Robert
- Laboratory of Biology and Modeling of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, Université de Lyon, Lyon, France
| | - D Hermand
- URPHYM-GEMO, The University of Namur, rue de Bruxelles, 61, Namur 5000 Belgium.
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35
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Tippens ND, Liang J, Leung AKY, Wierbowski SD, Ozer A, Booth JG, Lis JT, Yu H. Transcription imparts architecture, function and logic to enhancer units. Nat Genet 2020; 52:1067-1075. [PMID: 32958950 PMCID: PMC7541647 DOI: 10.1038/s41588-020-0686-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 07/28/2020] [Indexed: 01/09/2023]
Abstract
Distal enhancers play pivotal roles in development and disease yet remain one of the least understood regulatory elements. We used massively parallel reporter assays to perform functional comparisons of two leading enhancer models and find that gene-distal transcription start sites are robust predictors of active enhancers with higher resolution than histone modifications. We show that active enhancer units are precisely delineated by active transcription start sites, validate that these boundaries are sufficient for capturing enhancer function, and confirm that core promoter sequences are necessary for this activity. We assay adjacent enhancers and find that their joint activity is often driven by the stronger unit within the cluster. Finally, we validate these results through functional dissection of a distal enhancer cluster using CRISPR-Cas9 deletions. In summary, definition of high-resolution enhancer boundaries enables deconvolution of complex regulatory loci into modular units.
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Affiliation(s)
- Nathaniel D Tippens
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
- Department of Computational Biology, Cornell University, Ithaca, NY, USA
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Tri-Institutional Training Program in Computational Biology and Medicine, Cornell University, Ithaca, NY, USA
| | - Jin Liang
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Alden King-Yung Leung
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
- Department of Computational Biology, Cornell University, Ithaca, NY, USA
| | - Shayne D Wierbowski
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
- Department of Computational Biology, Cornell University, Ithaca, NY, USA
| | - Abdullah Ozer
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - James G Booth
- Department of Statistics and Data Science, Cornell University, Ithaca, NY, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.
- Tri-Institutional Training Program in Computational Biology and Medicine, Cornell University, Ithaca, NY, USA.
| | - Haiyuan Yu
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA.
- Department of Computational Biology, Cornell University, Ithaca, NY, USA.
- Tri-Institutional Training Program in Computational Biology and Medicine, Cornell University, Ithaca, NY, USA.
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36
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Liquid-liquid phase separation in biology: mechanisms, physiological functions and human diseases. SCIENCE CHINA. LIFE SCIENCES 2020; 63:953-985. [PMID: 32548680 DOI: 10.1007/s11427-020-1702-x] [Citation(s) in RCA: 151] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 04/20/2020] [Indexed: 02/06/2023]
Abstract
Cells are compartmentalized by numerous membrane-enclosed organelles and membraneless compartments to ensure that a wide variety of cellular activities occur in a spatially and temporally controlled manner. The molecular mechanisms underlying the dynamics of membrane-bound organelles, such as their fusion and fission, vesicle-mediated trafficking and membrane contactmediated inter-organelle interactions, have been extensively characterized. However, the molecular details of the assembly and functions of membraneless compartments remain elusive. Mounting evidence has emerged recently that a large number of membraneless compartments, collectively called biomacromolecular condensates, are assembled via liquid-liquid phase separation (LLPS). Phase-separated condensates participate in various biological activities, including higher-order chromatin organization, gene expression, triage of misfolded or unwanted proteins for autophagic degradation, assembly of signaling clusters and actin- and microtubule-based cytoskeletal networks, asymmetric segregations of cell fate determinants and formation of pre- and post-synaptic density signaling assemblies. Biomacromolecular condensates can transition into different material states such as gel-like structures and solid aggregates. The material properties of condensates are crucial for fulfilment of their distinct functions, such as biochemical reaction centers, signaling hubs and supporting architectures. Cells have evolved multiple mechanisms to ensure that biomacromolecular condensates are assembled and disassembled in a tightly controlled manner. Aberrant phase separation and transition are causatively associated with a variety of human diseases such as neurodegenerative diseases and cancers. This review summarizes recent major progress in elucidating the roles of LLPS in various biological pathways and diseases.
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37
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Quintero-Cadena P, Lenstra TL, Sternberg PW. RNA Pol II Length and Disorder Enable Cooperative Scaling of Transcriptional Bursting. Mol Cell 2020; 79:207-220.e8. [DOI: 10.1016/j.molcel.2020.05.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 04/09/2020] [Accepted: 05/19/2020] [Indexed: 12/15/2022]
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38
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Lyons DE, McMahon S, Ott M. A combinatorial view of old and new RNA polymerase II modifications. Transcription 2020; 11:66-82. [PMID: 32401151 DOI: 10.1080/21541264.2020.1762468] [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] [Indexed: 12/26/2022] Open
Abstract
The production of mRNA is a dynamic process that is highly regulated by reversible post-translational modifications of the C-terminal domain (CTD) of RNA polymerase II. The CTD is a highly repetitive domain consisting mostly of the consensus heptad sequence Tyr1-Ser2-Pro3-Thr4-Ser5-Pro6-Ser7. Phosphorylation of serine residues within this repeat sequence is well studied, but modifications of all residues have been described. Here, we focus on integrating newly identified and lesser-studied CTD post-translational modifications into the existing framework. We also review the growing body of work demonstrating crosstalk between different CTD modifications and the functional consequences of such crosstalk on the dynamics of transcriptional regulation.
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Affiliation(s)
- Danielle E Lyons
- Gladstone Institute of Virology and Immunology, San Francisco, CA, USA
| | - Sarah McMahon
- Gladstone Institute of Virology and Immunology, San Francisco, CA, USA.,Department of Medicine, University of California, San Francisco , San Francisco, CA, USA
| | - Melanie Ott
- Gladstone Institute of Virology and Immunology, San Francisco, CA, USA.,Department of Medicine, University of California, San Francisco , San Francisco, CA, USA
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39
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Manning SA, Kroeger B, Harvey KF. The regulation of Yorkie, YAP and TAZ: new insights into the Hippo pathway. Development 2020; 147:147/8/dev179069. [PMID: 32341025 DOI: 10.1242/dev.179069] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The Hippo pathway is a highly conserved signalling pathway that regulates multiple biological processes, including organ size control and cell fate. Since its discovery, genetic and biochemical studies have elucidated several key signalling steps important for pathway activation and deactivation. In recent years, technical advances in microscopy and genome modification have allowed new insights into Hippo signalling to be revealed. These studies have highlighted that the nuclear-cytoplasmic shuttling behaviour of the Hippo pathway transcriptional co-activators Yorkie, YAP and TAZ is far more dynamic than previously appreciated, and YAP and TAZ are also regulated by liquid-liquid phase separation. Here, we review our current understanding of Yorkie, YAP and TAZ regulation, with a focus on recent microscopy-based studies.
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Affiliation(s)
- Samuel A Manning
- Department of Anatomy and Developmental Biology, and Biomedicine Discovery Institute, Monash University, Clayton, Australia 3800
| | - Benjamin Kroeger
- Department of Anatomy and Developmental Biology, and Biomedicine Discovery Institute, Monash University, Clayton, Australia 3800
| | - Kieran F Harvey
- Department of Anatomy and Developmental Biology, and Biomedicine Discovery Institute, Monash University, Clayton, Australia 3800 .,Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, Victoria, Australia 3000.,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia 3010
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40
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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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Maita H, Nakagawa S. What is the switch for coupling transcription and splicing? RNA Polymerase II C‐terminal domain phosphorylation, phase separation and beyond. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 11:e1574. [DOI: 10.1002/wrna.1574] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 10/03/2019] [Accepted: 10/08/2019] [Indexed: 01/12/2023]
Affiliation(s)
- Hiroshi Maita
- RNA Biology Laboratory, Faculty of Pharmaceutical Sciences Hokkaido University Sapporo Japan
| | - Shinichi Nakagawa
- RNA Biology Laboratory, Faculty of Pharmaceutical Sciences Hokkaido University Sapporo Japan
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42
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Organization and regulation of gene transcription. Nature 2019; 573:45-54. [PMID: 31462772 DOI: 10.1038/s41586-019-1517-4] [Citation(s) in RCA: 350] [Impact Index Per Article: 70.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/30/2019] [Indexed: 12/18/2022]
Abstract
The regulated transcription of genes determines cell identity and function. Recent structural studies have elucidated mechanisms that govern the regulation of transcription by RNA polymerases during the initiation and elongation phases. Microscopy studies have revealed that transcription involves the condensation of factors in the cell nucleus. A model is emerging for the transcription of protein-coding genes in which distinct transient condensates form at gene promoters and in gene bodies to concentrate the factors required for transcription initiation and elongation, respectively. The transcribing enzyme RNA polymerase II may shuttle between these condensates in a phosphorylation-dependent manner. Molecular principles are being defined that rationalize transcriptional organization and regulation, and that will guide future investigations.
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Isaac RS, Churchman LS. The Long and the Short of the RNA Polymerase C-Terminal Domain and Phase Separation. Mol Cell 2019; 73:1087-1088. [PMID: 30901560 DOI: 10.1016/j.molcel.2019.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In this issue of Molecular Cell, Lu et al. (2019) analyze the role of the length and sequence complexity of the RNA polymerase II unstructured C-terminal domain in animal viability, development, and the dynamics of RNA polymerase II in vivo.
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Affiliation(s)
- R Stefan Isaac
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - L Stirling Churchman
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA.
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44
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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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