1
|
Chivu AG, Basso BA, Abuhashem A, Leger MM, Barshad G, Rice EJ, Vill AC, Wong W, Chou SP, Chovatiya G, Brady R, Smith JJ, Wikramanayake AH, Arenas-Mena C, Brito IL, Ruiz-Trillo I, Hadjantonakis AK, Lis JT, Lewis JJ, Danko CG. Evolution of promoter-proximal pausing enabled a new layer of transcription control. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.02.19.529146. [PMID: 39416036 PMCID: PMC11482795 DOI: 10.1101/2023.02.19.529146] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2024]
Abstract
Promoter-proximal pausing of RNA polymerase II (Pol II) is a key regulatory step during transcription. Despite the central role of pausing in gene regulation, we do not understand the evolutionary processes that led to the emergence of Pol II pausing or its transition to a rate-limiting step actively controlled by transcription factors. Here we analyzed transcription in species across the tree of life. Unicellular eukaryotes display a slow acceleration of Pol II near transcription start sites that transitioned to a longer-lived, focused pause in metazoans. This event coincided with the evolution of new subunits in the NELF and 7SK complexes. Depletion of NELF in mammals shifted the promoter-proximal buildup of Pol II from the pause site into the early gene body and compromised transcriptional activation for a set of heat shock genes. Our work details the evolutionary history of Pol II pausing and sheds light on how new transcriptional regulatory mechanisms evolve.
Collapse
|
2
|
Pessa JC, Joutsen J, Sistonen L. Transcriptional reprogramming at the intersection of the heat shock response and proteostasis. Mol Cell 2024; 84:80-93. [PMID: 38103561 DOI: 10.1016/j.molcel.2023.11.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/16/2023] [Accepted: 11/20/2023] [Indexed: 12/19/2023]
Abstract
Cellular homeostasis is constantly challenged by a myriad of extrinsic and intrinsic stressors. To mitigate the stress-induced damage, cells activate transient survival programs. The heat shock response (HSR) is an evolutionarily well-conserved survival program that is activated in response to proteotoxic stress. The HSR encompasses a dual regulation of transcription, characterized by rapid activation of genes encoding molecular chaperones and concomitant global attenuation of non-chaperone genes. Recent genome-wide approaches have delineated the molecular depth of stress-induced transcriptional reprogramming. The dramatic rewiring of gene and enhancer networks is driven by key transcription factors, including heat shock factors (HSFs), that together with chromatin-modifying enzymes remodel the 3D chromatin architecture, determining the selection of either gene activation or repression. Here, we highlight the current advancements of molecular mechanisms driving transcriptional reprogramming during acute heat stress. We also discuss the emerging implications of HSF-mediated stress signaling in the context of physiological and pathological conditions.
Collapse
Affiliation(s)
- Jenny C Pessa
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku, Finland
| | - Jenny Joutsen
- Department of Pathology, Lapland Central Hospital, Lapland Wellbeing Services County, Rovaniemi, Finland
| | - Lea Sistonen
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku, Finland.
| |
Collapse
|
3
|
Bunch H, Kim D, Naganuma M, Nakagawa R, Cong A, Jeong J, Ehara H, Vu H, Chang JH, Schellenberg MJ, Sekine SI. ERK2-topoisomerase II regulatory axis is important for gene activation in immediate early genes. Nat Commun 2023; 14:8341. [PMID: 38097570 PMCID: PMC10721843 DOI: 10.1038/s41467-023-44089-y] [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: 09/14/2022] [Accepted: 11/29/2023] [Indexed: 12/17/2023] Open
Abstract
The function of the mitogen-activated protein kinase signaling pathway is required for the activation of immediate early genes (IEGs), including EGR1 and FOS, for cell growth and proliferation. Recent studies have identified topoisomerase II (TOP2) as one of the important regulators of the transcriptional activation of IEGs. However, the mechanism underlying transcriptional regulation involving TOP2 in IEG activation has remained unknown. Here, we demonstrate that ERK2, but not ERK1, is important for IEG transcriptional activation and report a critical ELK1 binding sequence for ERK2 function at the EGR1 gene. Our data indicate that both ERK1 and ERK2 extensively phosphorylate the C-terminal domain of TOP2B at mutual and distinctive residues. Although both ERK1 and ERK2 enhance the catalytic rate of TOP2B required to relax positive DNA supercoiling, ERK2 delays TOP2B catalysis of negative DNA supercoiling. In addition, ERK1 may relax DNA supercoiling by itself. ERK2 catalytic inhibition or knock-down interferes with transcription and deregulates TOP2B in IEGs. Furthermore, we present the first cryo-EM structure of the human cell-purified TOP2B and etoposide together with the EGR1 transcriptional start site (-30 to +20) that has the strongest affinity to TOP2B within -423 to +332. The structure shows TOP2B-mediated breakage and dramatic bending of the DNA. Transcription is activated by etoposide, while it is inhibited by ICRF193 at EGR1 and FOS, suggesting that TOP2B-mediated DNA break to favor transcriptional activation. Taken together, this study suggests that activated ERK2 phosphorylates TOP2B to regulate TOP2-DNA interactions and favor transcriptional activation in IEGs. We propose that TOP2B association, catalysis, and dissociation on its substrate DNA are important processes for regulating transcription and that ERK2-mediated TOP2B phosphorylation may be key for the catalysis and dissociation steps.
Collapse
Affiliation(s)
- Heeyoun Bunch
- Department of Applied Biosciences, Kyungpook National University, Daegu, 41566, Republic of Korea.
- School of Applied Biosciences, College of Agriculture & Life Sciences, Kyungpook National University, Daegu, 41566, Republic of Korea.
| | - Deukyeong Kim
- School of Applied Biosciences, College of Agriculture & Life Sciences, Kyungpook National University, Daegu, 41566, Republic of Korea
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Masahiro Naganuma
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Reiko Nakagawa
- RIKEN BDR Laboratory for Phyloinformatics, Hyogo, 650-0047, Japan
| | - Anh Cong
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Jaehyeon Jeong
- Department of Applied Biosciences, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Haruhiko Ehara
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Hongha Vu
- Department of Biology Education, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Jeong Ho Chang
- Department of Biology Education, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Matthew J Schellenberg
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Shun-Ichi Sekine
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| |
Collapse
|
4
|
Nie X, Xu Q, Xu C, Chen F, Wang Q, Qin D, Wang R, Gao Z, Lu X, Yang X, Wu Y, Gu C, Xie W, Li L. Maternal TDP-43 interacts with RNA Pol II and regulates zygotic genome activation. Nat Commun 2023; 14:4275. [PMID: 37460529 DOI: 10.1038/s41467-023-39924-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 06/30/2023] [Indexed: 07/20/2023] Open
Abstract
Zygotic genome activation (ZGA) is essential for early embryonic development. However, the regulation of ZGA remains elusive in mammals. Here we report that a maternal factor TDP-43, a nuclear transactive response DNA-binding protein, regulates ZGA through RNA Pol II and is essential for mouse early embryogenesis. Maternal TDP-43 translocates from the cytoplasm into the nucleus at the early two-cell stage when minor to major ZGA transition occurs. Genetic deletion of maternal TDP-43 results in mouse early embryos arrested at the two-cell stage. TDP-43 co-occupies with RNA Pol II as large foci in the nucleus and also at the promoters of ZGA genes at the late two-cell stage. Biochemical evidence indicates that TDP-43 binds Polr2a and Cyclin T1. Depletion of maternal TDP-43 caused the loss of Pol II foci and reduced Pol II binding on chromatin at major ZGA genes, accompanied by defective ZGA. Collectively, our results suggest that maternal TDP-43 is critical for mouse early embryonic development, in part through facilitating the correct RNA Pol II configuration and zygotic genome activation.
Collapse
Affiliation(s)
- Xiaoqing Nie
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qianhua Xu
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, New Cornerstone Science Laboratory, School of Life Sciences, Tsinghua University, Beijing, China
- Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Chengpeng Xu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fengling Chen
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, New Cornerstone Science Laboratory, School of Life Sciences, Tsinghua University, Beijing, China
- Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Qizhi Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Dandan Qin
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Rui Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Zheng Gao
- Reproductive Medicine Center of the Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xukun Lu
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, New Cornerstone Science Laboratory, School of Life Sciences, Tsinghua University, Beijing, China
- Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Xinai Yang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yu Wu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chen Gu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wei Xie
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, New Cornerstone Science Laboratory, School of Life Sciences, Tsinghua University, Beijing, China.
- Tsinghua-Peking Center for Life Sciences, Beijing, China.
| | - Lei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Stem Cell and Regeneration, Beijing Institute of Stem Cell and Regenerative Medicine, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
5
|
Bhuiyan SH, Bordet G, Bamgbose G, Tulin AV. The Drosophila gene encoding JIG protein (CG14850) is critical for CrebA nuclear trafficking during development. Nucleic Acids Res 2023; 51:5647-5660. [PMID: 37144466 PMCID: PMC10287909 DOI: 10.1093/nar/gkad343] [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: 01/17/2022] [Revised: 04/16/2023] [Accepted: 04/25/2023] [Indexed: 05/06/2023] Open
Abstract
Coordination of mitochondrial and nuclear processes is key to the cellular health; however, very little is known about the molecular mechanisms regulating nuclear-mitochondrial crosstalk. Here, we report a novel molecular mechanism controlling the shuttling of CREB (cAMP response element-binding protein) protein complex between mitochondria and nucleoplasm. We show that a previously unknown protein, herein termed as Jig, functions as a tissue-specific and developmental timing-specific coregulator in the CREB pathway. Our results demonstrate that Jig shuttles between mitochondria and nucleoplasm, interacts with CrebA protein and controls its delivery to the nucleus, thus triggering CREB-dependent transcription in nuclear chromatin and mitochondria. Ablating the expression of Jig prevents CrebA from localizing to the nucleoplasm, affecting mitochondrial functioning and morphology and leads to Drosophila developmental arrest at the early third instar larval stage. Together, these results implicate Jig as an essential mediator of nuclear and mitochondrial processes. We also found that Jig belongs to a family of nine similar proteins, each of which has its own tissue- and time-specific expression profile. Thus, our results are the first to describe the molecular mechanism regulating nuclear and mitochondrial processes in a tissue- and time-specific manner.
Collapse
|
6
|
Pal S, Biswas D. Promoter-proximal regulation of gene transcription: Key factors involved and emerging role of general transcription factors in assisting productive elongation. Gene 2023:147571. [PMID: 37331491 DOI: 10.1016/j.gene.2023.147571] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/02/2023] [Accepted: 06/13/2023] [Indexed: 06/20/2023]
Abstract
The pausing of RNA polymerase II (Pol II) at the promoter-proximal sites is a key rate-limiting step in gene expression. Cells have dedicated a specific set of proteins that sequentially establish pause and then release the Pol II from promoter-proximal sites. A well-controlled pausing and subsequent release of Pol II is crucial for thefine tuning of expression of genes including signal-responsive and developmentally-regulated ones. The release of paused Pol II broadly involves its transition from initiation to elongation. In this review article, we will discuss the phenomenon of Pol II pausing, the underlying mechanism, and also the role of different known factors, with an emphasis on general transcription factors, involved in this overall regulation. We will further discuss some recent findings suggesting a possible role (underexplored) of initiation factors in assisting the transition of transcriptionally-engaged paused Pol II into productive elongation.
Collapse
Affiliation(s)
- Sujay Pal
- Laboratory of Transcription Biology, Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata - 32, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Debabrata Biswas
- Laboratory of Transcription Biology, Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata - 32, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
| |
Collapse
|
7
|
Zuñiga-Hernandez J, Meneses C, Bastias M, Allende ML, Glavic A. Drosophila DAxud1 Has a Repressive Transcription Activity on Hsp70 and Other Heat Shock Genes. Int J Mol Sci 2023; 24:ijms24087485. [PMID: 37108646 PMCID: PMC10138878 DOI: 10.3390/ijms24087485] [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: 01/05/2023] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
Drosophila melanogaster DAxud1 is a transcription factor that belongs to the Cysteine Serine Rich Nuclear Protein (CSRNP) family, conserved in metazoans, with a transcriptional transactivation activity. According to previous studies, this protein promotes apoptosis and Wnt signaling-mediated neural crest differentiation in vertebrates. However, no analysis has been conducted to determine what other genes it might control, especially in connection with cell survival and apoptosis. To partly answer this question, this work analyzes the role of Drosophila DAxud1 using Targeted-DamID-seq (TaDa-seq), which allows whole genome screening to determine in which regions it is most frequently found. This analysis confirmed the presence of DAxud1 in groups of pro-apoptotic and Wnt pathway genes, as previously described; furthermore, stress resistance genes that coding heat shock protein (HSP) family genes were found as hsp70, hsp67, and hsp26. The enrichment of DAxud1 also identified a DNA-binding motif (AYATACATAYATA) that is frequently found in the promoters of these genes. Surprisingly, the following analyses demonstrated that DAxud1 exerts a repressive role on these genes, which are necessary for cell survival. This is coupled with the pro-apoptotic and cell cycle arrest roles of DAxud1, in which repression of hsp70 complements the maintenance of tissue homeostasis through cell survival modulation.
Collapse
Affiliation(s)
- Jorge Zuñiga-Hernandez
- Millennium Institute Center for Genome Regulation (CGR), Department of Biology, Faculty of Sciences, University of Chile, Santiago 7800003, Chile
| | - Claudio Meneses
- Millennium Institute Center for Genome Regulation (CGR), Department of Biology, Faculty of Sciences, University of Chile, Santiago 7800003, Chile
- Millennium Nucleus Development of Super Adaptable Plants (MN-SAP), Santiago 8331150, Chile
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Macarena Bastias
- Centro de Biotecnología vegetal, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago 8370035, Chile
| | - Miguel L Allende
- Millennium Institute Center for Genome Regulation (CGR), Department of Biology, Faculty of Sciences, University of Chile, Santiago 7800003, Chile
| | - Alvaro Glavic
- Millennium Institute Center for Genome Regulation (CGR), Department of Biology, Faculty of Sciences, University of Chile, Santiago 7800003, Chile
| |
Collapse
|
8
|
Welsh SA, Gardini A. Genomic regulation of transcription and RNA processing by the multitasking Integrator complex. Nat Rev Mol Cell Biol 2023; 24:204-220. [PMID: 36180603 PMCID: PMC9974566 DOI: 10.1038/s41580-022-00534-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2022] [Indexed: 11/09/2022]
Abstract
In higher eukaryotes, fine-tuned activation of protein-coding genes and many non-coding RNAs pivots around the regulated activity of RNA polymerase II (Pol II). The Integrator complex is the only Pol II-associated large multiprotein complex that is metazoan specific, and has therefore been understudied for years. Integrator comprises at least 14 subunits, which are grouped into distinct functional modules. The phosphodiesterase activity of the core catalytic module is co-transcriptionally directed against several RNA species, including long non-coding RNAs (lncRNAs), U small nuclear RNAs (U snRNAs), PIWI-interacting RNAs (piRNAs), enhancer RNAs and nascent pre-mRNAs. Processing of non-coding RNAs by Integrator is essential for their biogenesis, and at protein-coding genes, Integrator is a key modulator of Pol II promoter-proximal pausing and transcript elongation. Recent studies have identified an Integrator-specific serine/threonine-protein phosphatase 2A (PP2A) module, which targets Pol II and other components of the basal transcription machinery. In this Review, we discuss how the activity of Integrator regulates transcription, RNA processing, chromatin landscape and DNA repair. We also discuss the diverse roles of Integrator in development and tumorigenesis.
Collapse
|
9
|
Bunch H. Studying RNA Polymerase II Promoter-Proximal Pausing by In Vitro Immobilized Template and Transcription Assays. Methods Mol Biol 2023; 2693:13-24. [PMID: 37540423 DOI: 10.1007/978-1-0716-3342-7_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
The immobilized template assay is a versatile biochemical method for studying protein-nucleic acid interactions. Using this method, immobilized nucleic acid-associated or specific proteins can be identified and quantified by techniques such as mass spectrometry and immunoblotting. Here, a modified immobilized template assay combined with in vitro transcription assay to study the function of transcription factors and transcriptional activities at the human heat shock protein 70 (HSP70) gene is described. Notably, this method can be applied to study other important genes and transcription factors in vitro.
Collapse
Affiliation(s)
- Heeyoun Bunch
- Department of Applied Biosciences, Kyungpook National University, Daegu, Republic of Korea
| |
Collapse
|
10
|
Cugusi S, Bajpe PK, Mitter R, Patel H, Stewart A, Svejstrup JQ. An Important Role for RPRD1B in the Heat Shock Response. Mol Cell Biol 2022; 42:e0017322. [PMID: 36121223 PMCID: PMC9583720 DOI: 10.1128/mcb.00173-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/07/2022] [Accepted: 08/26/2022] [Indexed: 12/25/2022] Open
Abstract
During the heat shock response (HSR), heat shock factor (HSF1 in mammals) binds to target gene promoters, resulting in increased expression of heat shock proteins that help maintain protein homeostasis and ensure cell survival. Besides HSF1, only a relatively few transcription factors with a specific role in ensuring correctly regulated gene expression during the HSR have been described. Here, we use proteomic and genomic (CRISPR) screening to identify a role for RPRD1B in the response to heat shock. Indeed, cells depleted for RPRD1B are heat shock sensitive and show decreased expression of key heat shock proteins (HSPs). These results add to our understanding of the connection between basic gene expression mechanisms and the HSR.
Collapse
Affiliation(s)
- Simona Cugusi
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Prashanth Kumar Bajpe
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Richard Mitter
- Bioinformatics and Biostatistics, The Francis Crick Institute, London, United Kingdom
| | - Harshil Patel
- Bioinformatics and Biostatistics, The Francis Crick Institute, London, United Kingdom
| | - Aengus Stewart
- Bioinformatics and Biostatistics, The Francis Crick Institute, London, United Kingdom
| | - Jesper Q. Svejstrup
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, London, United Kingdom
- Department of Cellular and Molecular Medicine, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
11
|
Sawarkar R. Transcriptional lockdown during acute proteotoxic stress. Trends Biochem Sci 2022; 47:660-672. [PMID: 35487807 PMCID: PMC9041648 DOI: 10.1016/j.tibs.2022.03.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 03/20/2022] [Accepted: 03/31/2022] [Indexed: 12/02/2022]
Abstract
Cells experiencing proteotoxic stress downregulate the expression of thousands of active genes and upregulate a few stress-response genes. The strategy of downregulating gene expression has conceptual parallels with general lockdown in the global response to the coronavirus disease 2019 (COVID-19) pandemic. The mechanistic details of global transcriptional downregulation of genes, termed stress-induced transcriptional attenuation (SITA), are only beginning to emerge. The reduction in RNA and protein production during stress may spare proteostasis capacity, allowing cells to divert resources to control stress-induced damage. Given the relevance of translational downregulation in a broad variety of diseases, the role of SITA in diseases caused by proteotoxicity should be investigated in future, paving the way for potential novel therapeutics.
Collapse
Affiliation(s)
- Ritwick Sawarkar
- Medical Research Council (MRC), University of Cambridge, Cambridge, UK.
| |
Collapse
|
12
|
Kinetic principles underlying pioneer function of GAGA transcription factor in live cells. Nat Struct Mol Biol 2022; 29:665-676. [PMID: 35835866 PMCID: PMC10177624 DOI: 10.1038/s41594-022-00800-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 05/27/2022] [Indexed: 11/09/2022]
Abstract
How pioneer factors interface with chromatin to promote accessibility for transcription control is poorly understood in vivo. Here, we directly visualize chromatin association by the prototypical GAGA pioneer factor (GAF) in live Drosophila hemocytes. Single-particle tracking reveals that most GAF is chromatin bound, with a stable-binding fraction showing nucleosome-like confinement residing on chromatin for more than 2 min, far longer than the dynamic range of most transcription factors. These kinetic properties require the full complement of GAF's DNA-binding, multimerization and intrinsically disordered domains, and are autonomous from recruited chromatin remodelers NURF and PBAP, whose activities primarily benefit GAF's neighbors such as Heat Shock Factor. Evaluation of GAF kinetics together with its endogenous abundance indicates that, despite on-off dynamics, GAF constitutively and fully occupies major chromatin targets, thereby providing a temporal mechanism that sustains open chromatin for transcriptional responses to homeostatic, environmental and developmental signals.
Collapse
|
13
|
Himanen SV, Puustinen MC, Da Silva AJ, Vihervaara A, Sistonen L. HSFs drive transcription of distinct genes and enhancers during oxidative stress and heat shock. Nucleic Acids Res 2022; 50:6102-6115. [PMID: 35687139 PMCID: PMC9226494 DOI: 10.1093/nar/gkac493] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 05/25/2022] [Indexed: 11/13/2022] Open
Abstract
Reprogramming of transcription is critical for the survival under cellular stress. Heat shock has provided an excellent model to investigate nascent transcription in stressed cells, but the molecular mechanisms orchestrating RNA synthesis during other types of stress are unknown. We utilized PRO-seq and ChIP-seq to study how Heat Shock Factors, HSF1 and HSF2, coordinate transcription at genes and enhancers upon oxidative stress and heat shock. We show that pause-release of RNA polymerase II (Pol II) is a universal mechanism regulating gene transcription in stressed cells, while enhancers are activated at the level of Pol II recruitment. Moreover, besides functioning as conventional promoter-binding transcription factors, HSF1 and HSF2 bind to stress-induced enhancers to trigger Pol II pause-release from poised gene promoters. Importantly, HSFs act at distinct genes and enhancers in a stress type-specific manner. HSF1 binds to many chaperone genes upon oxidative and heat stress but activates them only in heat-shocked cells. Under oxidative stress, HSF1 localizes to a unique set of promoters and enhancers to trans-activate oxidative stress-specific genes. Taken together, we show that HSFs function as multi-stress-responsive factors that activate distinct genes and enhancers when encountering changes in temperature and redox state.
Collapse
Affiliation(s)
- Samu V Himanen
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, 20520 Turku, Finland.,Turku Bioscience Centre, University of Turku and Åbo Akademi University, 20520 Turku, Finland
| | - Mikael C Puustinen
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, 20520 Turku, Finland.,Turku Bioscience Centre, University of Turku and Åbo Akademi University, 20520 Turku, Finland
| | - Alejandro J Da Silva
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, 20520 Turku, Finland.,Turku Bioscience Centre, University of Turku and Åbo Akademi University, 20520 Turku, Finland
| | - Anniina Vihervaara
- Department of Gene Technology, Science for Life Laboratory, KTH Royal Institute of Technology, 17165 Stockholm, Sweden
| | - Lea Sistonen
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, 20520 Turku, Finland.,Turku Bioscience Centre, University of Turku and Åbo Akademi University, 20520 Turku, Finland
| |
Collapse
|
14
|
Differential cofactor dependencies define distinct types of human enhancers. Nature 2022; 606:406-413. [PMID: 35650434 PMCID: PMC7613064 DOI: 10.1038/s41586-022-04779-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 04/20/2022] [Indexed: 12/24/2022]
Abstract
All multicellular organisms rely on differential gene transcription regulated by genomic enhancers, which function through cofactors that are recruited by transcription factors1,2. Emerging evidence suggests that not all cofactors are required at all enhancers3-5, yet whether these observations reflect more general principles or distinct types of enhancers remained unknown. Here we categorized human enhancers by their cofactor dependencies and show that these categories provide a framework to understand the sequence and chromatin diversity of enhancers and their roles in different gene-regulatory programmes. We quantified enhancer activities along the entire human genome using STARR-seq6 in HCT116 cells, following the rapid degradation of eight cofactors. This analysis identified different types of enhancers with distinct cofactor requirements, sequences and chromatin properties. Some enhancers were insensitive to the depletion of the core Mediator subunit MED14 or the bromodomain protein BRD4 and regulated distinct transcriptional programmes. In particular, canonical Mediator7 seemed dispensable for P53-responsive enhancers, and MED14-depleted cells induced endogenous P53 target genes. Similarly, BRD4 was not required for the transcription of genes that bear CCAAT boxes and a TATA box (including histone genes and LTR12 retrotransposons) or for the induction of heat-shock genes. This categorization of enhancers through cofactor dependencies reveals distinct enhancer types that can bypass broadly utilized cofactors, which illustrates how alternative ways to activate transcription separate gene expression programmes and provide a conceptual framework to understand enhancer function and regulatory specificity.
Collapse
|
15
|
Alagar Boopathy LR, Jacob-Tomas S, Alecki C, Vera M. Mechanisms tailoring the expression of heat shock proteins to proteostasis challenges. J Biol Chem 2022; 298:101796. [PMID: 35248532 PMCID: PMC9065632 DOI: 10.1016/j.jbc.2022.101796] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 02/23/2022] [Accepted: 02/25/2022] [Indexed: 12/14/2022] Open
Abstract
All cells possess an internal stress response to cope with environmental and pathophysiological challenges. Upon stress, cells reprogram their molecular functions to activate a survival mechanism known as the heat shock response, which mediates the rapid induction of molecular chaperones such as the heat shock proteins (HSPs). This potent production overcomes the general suppression of gene expression and results in high levels of HSPs to subsequently refold or degrade misfolded proteins. Once the damage or stress is repaired or removed, cells terminate the production of HSPs and resume regular functions. Thus, fulfillment of the stress response requires swift and robust coordination between stress response activation and completion that is determined by the status of the cell. In recent years, single-cell fluorescence microscopy techniques have begun to be used in unravelling HSP-gene expression pathways, from DNA transcription to mRNA degradation. In this review, we will address the molecular mechanisms in different organisms and cell types that coordinate the expression of HSPs with signaling networks that act to reprogram gene transcription, mRNA translation, and decay and ensure protein quality control.
Collapse
|
16
|
Szádeczky-Kardoss I, Szaker H, Verma R, Darkó É, Pettkó-Szandtner A, Silhavy D, Csorba T. Elongation factor TFIIS is essential for heat stress adaptation in plants. Nucleic Acids Res 2022; 50:1927-1950. [PMID: 35100405 PMCID: PMC8886746 DOI: 10.1093/nar/gkac020] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 12/11/2021] [Accepted: 01/06/2022] [Indexed: 12/22/2022] Open
Abstract
Elongation factor TFIIS (transcription factor IIS) is structurally and biochemically probably the best characterized elongation cofactor of RNA polymerase II. However, little is known about TFIIS regulation or its roles during stress responses. Here, we show that, although TFIIS seems unnecessary under optimal conditions in Arabidopsis, its absence renders plants supersensitive to heat; tfIIs mutants die even when exposed to sublethal high temperature. TFIIS activity is required for thermal adaptation throughout the whole life cycle of plants, ensuring both survival and reproductive success. By employing a transcriptome analysis, we unravel that the absence of TFIIS makes transcriptional reprogramming sluggish, and affects expression and alternative splicing pattern of hundreds of heat-regulated transcripts. Transcriptome changes indirectly cause proteotoxic stress and deterioration of cellular pathways, including photosynthesis, which finally leads to lethality. Contrary to expectations of being constantly present to support transcription, we show that TFIIS is dynamically regulated. TFIIS accumulation during heat occurs in evolutionary distant species, including the unicellular alga Chlamydomonas reinhardtii, dicot Brassica napus and monocot Hordeum vulgare, suggesting that the vital role of TFIIS in stress adaptation of plants is conserved.
Collapse
Affiliation(s)
- István Szádeczky-Kardoss
- Genetics and Biotechnology Institute, MATE University, Szent-Györgyi A. u. 4, 2100 Gödöllő, Hungary
| | - Henrik Mihály Szaker
- Genetics and Biotechnology Institute, MATE University, Szent-Györgyi A. u. 4, 2100 Gödöllő, Hungary
- Faculty of Natural Sciences, Eötvös Lóránd University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary
- Institute of Plant Biology, Biological Research Centre, Temesvári krt. 62., 6726 Szeged, Hungary
| | - Radhika Verma
- Genetics and Biotechnology Institute, MATE University, Szent-Györgyi A. u. 4, 2100 Gödöllő, Hungary
- Doctorate School of Biological Sciences, MATE University, Pater Karoly u. 1, 2100 Gödöllő, Hungary
| | - Éva Darkó
- Agricultural Institute, Centre for Agricultural Research, Brunszvik u. 2., 2462 Martonvásár, Hungary
| | | | - Dániel Silhavy
- Institute of Plant Biology, Biological Research Centre, Temesvári krt. 62., 6726 Szeged, Hungary
| | - Tibor Csorba
- Genetics and Biotechnology Institute, MATE University, Szent-Györgyi A. u. 4, 2100 Gödöllő, Hungary
| |
Collapse
|
17
|
Lu WC, Omari R, Ray H, Wang J, Williams I, Jacobs C, Hockaden N, Bochman ML, Carpenter RL. AKT1 mediates multiple phosphorylation events that functionally promote HSF1 activation. FEBS J 2022; 289:3876-3893. [PMID: 35080342 PMCID: PMC9309721 DOI: 10.1111/febs.16375] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 12/22/2021] [Accepted: 01/24/2022] [Indexed: 12/26/2022]
Abstract
The heat stress response activates the transcription factor heat shock factor 1 (HSF1), which subsequently upregulates heat shock proteins to maintain the integrity of the proteome. HSF1 activation requires nuclear localization, trimerization, DNA binding, phosphorylation and gene transactivation. Phosphorylation at S326 is an important regulator of HSF1 transcriptional activity. Phosphorylation at S326 is mediated by AKT1, mTOR, p38, MEK1 and DYRK2. Here, we observed activation of HSF1 by AKT1 independently of mTOR. AKT2 also phosphorylated S326 of HSF1 but showed weak ability to activate HSF1. Similarly, mTOR, p38, MEK1 and DYRK2 all phosphorylated S326 but AKT1 was the most potent activator. Mass spectrometry showed that AKT1 also phosphorylated HSF1 at T142, S230 and T527 in addition to S326, whereas the other kinases did not. Subsequent investigation revealed that phosphorylation at T142 is necessary for HSF1 trimerization and that S230, S326 and T527 are required for HSF1 gene transactivation and recruitment of TFIIB and CDK9. Interestingly, T527 as a phosphorylated residue has not been previously shown and sits in the transactivation domain, further implying a role for this site in HSF1 gene transactivation. This study suggests that HSF1 hyperphosphorylation is targeted and these specific residues have direct function in regulating HSF1 transcriptional activity.
Collapse
Affiliation(s)
- Wen-Cheng Lu
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN, USA
| | - Ramsey Omari
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN, USA
| | - Haimanti Ray
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN, USA
| | - John Wang
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN, USA
| | - Imade Williams
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN, USA
| | - Curteisha Jacobs
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN, USA
| | - Natasha Hockaden
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN, USA
| | - Matthew L Bochman
- Molecular and Cellular Biochemistry Department, Indiana University, Bloomington, IN, USA.,Melvin and Bren Simon Comprehensive Cancer Center, Indiana University School of Medicine, IN, USA
| | - Richard L Carpenter
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, IN, USA.,Melvin and Bren Simon Comprehensive Cancer Center, Indiana University School of Medicine, IN, USA
| |
Collapse
|
18
|
Kaiser C, Bradu A, Gamble N, Caldwell JA, Koh AS. AIRE in context: Leveraging chromatin plasticity to trigger ectopic gene expression. Immunol Rev 2022; 305:59-76. [PMID: 34545959 PMCID: PMC9250823 DOI: 10.1111/imr.13026] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 08/26/2021] [Indexed: 12/22/2022]
Abstract
The emergence of antigen receptor diversity in clonotypic lymphocytes drove the evolution of a novel gene, Aire, that enabled the adaptive immune system to discriminate foreign invaders from self-constituents. AIRE functions in the epithelial cells of the thymus to express genes highly restricted to alternative cell lineages. This somatic plasticity facilitates the selection of a balanced repertoire of T cells that protects the host from harmful self-reactive clones, yet maintains a wide range of affinities for virtually any foreign antigen. Here, we review the latest understanding of AIRE's molecular actions with a focus on its interplay with chromatin. We argue that AIRE is a multi-valent chromatin effector that acts late in the transcription cycle to modulate the activity of previously poised non-coding regulatory elements of tissue-specific genes. We postulate a role for chromatin instability-caused in part by ATP-dependent chromatin remodeling-that variably sets the scope of the accessible landscape on which AIRE can act. We highlight AIRE's intrinsic repressive function and its relevance in providing feedback control. We synthesize these recent advances into a putative model for the mechanistic modes by which AIRE triggers ectopic transcription for immune repertoire selection.
Collapse
Affiliation(s)
- Caroline Kaiser
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
- Department of Human Genetics, University of Chicago, Chicago, Illinois, USA
| | - Alexandra Bradu
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
| | - Noah Gamble
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
- Graduate Program in Biophysical Sciences, University of Chicago, Chicago, Illinois, USA
| | - Jason A. Caldwell
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
| | - Andrew S. Koh
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, Illinois, USA
| |
Collapse
|
19
|
Bordet G, Kotova E, Tulin AV. Poly(ADP-ribosyl)ating pathway regulates development from stem cell niche to longevity control. Life Sci Alliance 2021; 5:5/3/e202101071. [PMID: 34949666 PMCID: PMC8739260 DOI: 10.26508/lsa.202101071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 02/07/2023] Open
Abstract
The regulation of poly(ADP-ribose) polymerase, the enzyme responsible for the synthesis of homopolymer ADP-ribose chains on nuclear proteins, has been extensively studied over the last decades for its involvement in tumorigenesis processes. However, the regulation of poly(ADP-ribose) glycohydrolase (PARG), the enzyme responsible for removing this posttranslational modification, has attracted little attention. Here we identified that PARG activity is partly regulated by two phosphorylation sites, ph1 and ph2, in Drosophila We showed that the disruption of these sites affects the germline stem-cells maintenance/differentiation balance as well as embryonic and larval development, but also the synchronization of egg production with the availability of a calorically sufficient food source. Moreover, these PARG phosphorylation sites play an essential role in the control of fly survivability from larvae to adults. We also showed that PARG is phosphorylated by casein kinase 2 and that this phosphorylation seems to protect PARG protein against degradation in vivo. Taken together, these results suggest that the regulation of PARG protein activity plays a crucial role in the control of several developmental processes.
Collapse
|
20
|
Xu X, Mann M, Qiao D, Li Y, Zhou J, Brasier AR. Bromodomain Containing Protein 4 (BRD4) Regulates Expression of its Interacting Coactivators in the Innate Response to Respiratory Syncytial Virus. Front Mol Biosci 2021; 8:728661. [PMID: 34765643 PMCID: PMC8577543 DOI: 10.3389/fmolb.2021.728661] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 09/24/2021] [Indexed: 12/12/2022] Open
Abstract
Bromodomain-containing protein 4 plays a central role in coordinating the complex epigenetic component of the innate immune response. Previous studies implicated BRD4 as a component of a chromatin-modifying complex that is dynamically recruited to a network of protective cytokines by binding activated transcription factors, polymerases, and histones to trigger their rapid expression via transcriptional elongation. Our previous study extended our understanding of the airway epithelial BRD4 interactome by identifying over 100 functionally important coactivators and transcription factors, whose association is induced by respiratory syncytial virus (RSV) infection. RSV is an etiological agent of recurrent respiratory tract infections associated with exacerbations of chronic obstructive pulmonary disease. Using a highly selective small-molecule BRD4 inhibitor (ZL0454) developed by us, we extend these findings to identify the gene regulatory network dependent on BRD4 bromodomain (BD) interactions. Human small airway epithelial cells were infected in the absence or presence of ZL0454, and gene expression profiling was performed. A highly reproducible dataset was obtained which indicated that BRD4 mediates both activation and repression of RSV-inducible gene regulatory networks controlling cytokine expression, interferon (IFN) production, and extracellular matrix remodeling. Index genes of functionally significant clusters were validated independently. We discover that BRD4 regulates the expression of its own gene during the innate immune response. Interestingly, BRD4 activates the expression of NFκB/RelA, a coactivator that binds to BRD4 in a BD-dependent manner. We extend this finding to show that BRD4 also regulates other components of its functional interactome, including the Mediator (Med) coactivator complex and the SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin (SMARC) subunits. To provide further insight into mechanisms for BRD4 in RSV expression, we mapped 7,845 RSV-inducible Tn5 transposase peaks onto the BRD4-dependent gene bodies. These were located in promoters and introns of cytostructural and extracellular matrix (ECM) formation genes. These data indicate that BRD4 mediates the dynamic response of airway epithelial cells to RNA infection by modulating the expression of its coactivators, controlling the expression of host defense mechanisms and remodeling genes through changes in promoter accessibility.
Collapse
Affiliation(s)
- Xiaofang Xu
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Morgan Mann
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Dianhua Qiao
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Yi Li
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Jia Zhou
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Allan R Brasier
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States.,Institute for Clinical and Translational Research (ICTR), University of Wisconsin-Madison, Madison, WI, United States
| |
Collapse
|
21
|
Ngian Z, Lin W, Ong C. NELF-A controls Drosophila healthspan by regulating heat-shock protein-mediated cellular protection and heterochromatin maintenance. Aging Cell 2021; 20:e13348. [PMID: 33788376 PMCID: PMC8135010 DOI: 10.1111/acel.13348] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 02/05/2021] [Accepted: 02/09/2021] [Indexed: 11/29/2022] Open
Abstract
NELF‐mediated pausing of RNA polymerase II (RNAPII) constitutes a crucial step in transcription regulation. However, it remains unclear how control release of RNAPII pausing can affect the epigenome and regulate important aspects of animal physiology like aging. We found that NELF‐A dosage regulates Drosophila healthspan: Halving NELF‐A level in the heterozygous mutants or via neuronal‐specific RNAi depletion improves their locomotor activity, stress resistance, and lifespan significantly. Conversely, NELF‐A overexpression shortens fly lifespan drastically. Mechanistically, lowering NELF‐A level facilitates the release of paused RNAPII for productive transcription of the heat‐shock protein (Hsp) genes. The elevated HSPs expression in turn attenuates the accumulation of insoluble protein aggregates, reactive oxidative species, DNA damage and systemic inflammation in the brains of aging NELF‐A depleted flies as compared to their control siblings. This pro‐longevity effect is unique to NELF‐A due to its higher expression level and more efficient pausing of RNAPII than other NELF subunits. Importantly, enhanced resistance to oxidative stress in NELF‐A heterozygous mutants is highly conserved such that knocking down its level in human SH‐SY5Y cells attenuates hydrogen peroxide‐induced DNA damage and apoptosis. Depleting NELF‐A reconfigures the epigenome through the maintenance of H3K9me2‐enriched heterochromatin during aging, leading to the repression of specific retrotransposons like Gypsy‐1 in the brains of NELF‐A mutants. Taken together, we showed that the dosage of neuronal NELF‐A affects multiple aspects of aging in Drosophila by regulating transcription of Hsp genes in the brains, suggesting that targeting transcription elongation might be a viable therapeutic strategy against age‐onset diseases like neurodegeneration.
Collapse
Affiliation(s)
- Zhen‐Kai Ngian
- Temasek Life Sciences Laboratory National University of Singapore Singapore Singapore
- Department of Biological Sciences National University of Singapore Singapore Singapore
| | - Wei‐Qi Lin
- Temasek Life Sciences Laboratory National University of Singapore Singapore Singapore
| | - Chin‐Tong Ong
- Temasek Life Sciences Laboratory National University of Singapore Singapore Singapore
- Department of Biological Sciences National University of Singapore Singapore Singapore
| |
Collapse
|
22
|
Zheng B, Aoi Y, Shah AP, Iwanaszko M, Das S, Rendleman EJ, Zha D, Khan N, Smith ER, Shilatifard A. Acute perturbation strategies in interrogating RNA polymerase II elongation factor function in gene expression. Genes Dev 2021; 35:273-285. [PMID: 33446572 PMCID: PMC7849361 DOI: 10.1101/gad.346106.120] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 12/03/2020] [Indexed: 12/20/2022]
Abstract
The regulation of gene expression catalyzed by RNA polymerase II (Pol II) requires a host of accessory factors to ensure cell growth, differentiation, and survival under environmental stress. Here, using the auxin-inducible degradation (AID) system to study transcriptional activities of the bromodomain and extraterminal domain (BET) and super elongation complex (SEC) families, we found that the CDK9-containing BRD4 complex is required for the release of Pol II from promoter-proximal pausing for most genes, while the CDK9-containing SEC is required for activated transcription in the heat shock response. By using both the proteolysis targeting chimera (PROTAC) dBET6 and the AID system, we found that dBET6 treatment results in two major effects: increased pausing due to BRD4 loss, and reduced enhancer activity attributable to BRD2 loss. In the heat shock response, while auxin-mediated depletion of the AFF4 subunit of the SEC has a more severe defect than AFF1 depletion, simultaneous depletion of AFF1 and AFF4 leads to a stronger attenuation of the heat shock response, similar to treatment with the SEC inhibitor KL-1, suggesting a possible redundancy among SEC family members. This study highlights the usefulness of orthogonal acute depletion/inhibition strategies to identify distinct and redundant biological functions among Pol II elongation factor paralogs.
Collapse
Affiliation(s)
- Bin Zheng
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Yuki Aoi
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Avani P Shah
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Marta Iwanaszko
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Siddhartha Das
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Emily J Rendleman
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Didi Zha
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Nabiha Khan
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Edwin R Smith
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Ali Shilatifard
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| |
Collapse
|
23
|
Abstract
More than 30% of genes in higher eukaryotes are regulated by RNA polymerase II (Pol II) promoter proximal pausing. Pausing is released by the positive transcription elongation factor complex (P-TEFb). However, the exact mechanism by which this occurs and whether phosphorylation of the carboxyl-terminal domain of Pol II is involved in the process remains unknown. We previously reported that JMJD5 could generate tailless nucleosomes at position +1 from transcription start sites (TSS), thus perhaps enable progression of Pol II. Here we find that knockout of JMJD5 leads to accumulation of nucleosomes at position +1. Absence of JMJD5 also results in loss of or lowered transcription of a large number of genes. Interestingly, we found that phosphorylation, by CDK9, of Ser2 within two neighboring heptad repeats in the carboxyl-terminal domain of Pol II, together with phosphorylation of Ser5 within the second repeat, HR-Ser2p (1, 2)-Ser5p (2) for short, allows Pol II to bind JMJD5 via engagement of the N-terminal domain of JMJD5. We suggest that these events bring JMJD5 near the nucleosome at position +1, thus allowing JMJD5 to clip histones on this nucleosome, a phenomenon that may contribute to release of Pol II pausing.
Collapse
|
24
|
HSF1 inhibition attenuates HIV-1 latency reversal mediated by several candidate LRAs In Vitro and Ex Vivo. Proc Natl Acad Sci U S A 2020; 117:15763-15771. [PMID: 32571938 DOI: 10.1073/pnas.1916290117] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
HIV-1 latency is a major barrier to cure. Identification of small molecules that destabilize latency and allow immune clearance of infected cells could lead to treatment-free remission. In vitro models of HIV-1 latency involving cell lines or primary cells have been developed for characterization of HIV-1 latency and high-throughput screening for latency-reversing agents (LRAs). We have shown that the majority of LRAs identified to date are relatively ineffective in cells from infected individuals despite activity in model systems. We show here that, for diverse LRAs, latency reversal observed in model systems involves a heat shock factor 1 (HSF1)-mediated stress pathway. Small-molecule inhibition of HSF1 attenuated HIV-1 latency reversal by histone deactylase inhibitors, protein kinase C agonists, and proteasome inhibitors without interfering with the known mechanism of action of these LRAs. However, latency reversal by second mitochondria-derived activator of caspase (SMAC) mimetics was not affected by inhibition of HSF1. In cells from infected individuals, inhibition of HSF1 attenuated latency reversal by phorbol ester+ionomycin but not by anti-CD3+anti-CD28. HSF1 promotes elongation of HIV-1 RNA by recruiting P-TEFb to the HIV-1 long terminal repeat (LTR), and we show that inhibition of HSF1 attenuates the formation of elongated HIV-1 transcripts. We demonstrate that in vitro models of latency have higher levels of the P-TEFb subunit cyclin T1 than primary cells, which may explain why many LRAs are functional in model systems but relatively ineffective in primary cells. Together, these studies provide insights into why particular LRA combinations are effective in reversing latency in cells from infected individuals.
Collapse
|
25
|
Bacon CW, Challa A, Hyder U, Shukla A, Borkar AN, Bayo J, Liu J, Wu SY, Chiang CM, Kutateladze TG, D'Orso I. KAP1 Is a Chromatin Reader that Couples Steps of RNA Polymerase II Transcription to Sustain Oncogenic Programs. Mol Cell 2020; 78:1133-1151.e14. [PMID: 32402252 PMCID: PMC7305985 DOI: 10.1016/j.molcel.2020.04.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 02/25/2020] [Accepted: 04/17/2020] [Indexed: 01/08/2023]
Abstract
Precise control of the RNA polymerase II (RNA Pol II) cycle, including pausing and pause release, maintains transcriptional homeostasis and organismal functions. Despite previous work to understand individual transcription steps, we reveal a mechanism that integrates RNA Pol II cycle transitions. Surprisingly, KAP1/TRIM28 uses a previously uncharacterized chromatin reader cassette to bind hypo-acetylated histone 4 tails at promoters, guaranteeing continuous progression of RNA Pol II entry to and exit from the pause state. Upon chromatin docking, KAP1 first associates with RNA Pol II and then recruits a pathway-specific transcription factor (SMAD2) in response to cognate ligands, enabling gene-selective CDK9-dependent pause release. This coupling mechanism is exploited by tumor cells to aberrantly sustain transcriptional programs commonly dysregulated in cancer patients. The discovery of a factor integrating transcription steps expands the functional repertoire by which chromatin readers operate and provides mechanistic understanding of transcription regulation, offering alternative therapeutic opportunities to target transcriptional dysregulation.
Collapse
Affiliation(s)
- Curtis W Bacon
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Biological Chemistry Graduate Program, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ashwini Challa
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Usman Hyder
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ashutosh Shukla
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Aditi N Borkar
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Juan Bayo
- Instituto de Investigaciones en Medicina Traslacional, Facultad de Ciencias Biomédicas, CONICET, Universidad Austral, Derqui-Pilar, Buenos Aires 1629, Argentina
| | - Jiuyang Liu
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Shwu-Yuan Wu
- Harold C. Simmons Comprehensive Cancer Center, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biochemistry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Cheng-Ming Chiang
- Harold C. Simmons Comprehensive Cancer Center, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biochemistry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Pharmacology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tatiana G Kutateladze
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Iván D'Orso
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|
26
|
Wang Y, Qiu T. Positive transcription elongation factor b and its regulators in development. ALL LIFE 2020. [DOI: 10.1080/21553769.2019.1663277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Affiliation(s)
- Yan Wang
- Department of Pediatrics, West China Second University Hospital, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, People’s Republic of China
| | - Tong Qiu
- Department of Pediatrics, West China Second University Hospital, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, People’s Republic of China
| |
Collapse
|
27
|
In S, Kim YI, Lee JE, Kim J. RNF20/40-mediated eEF1BδL monoubiquitylation stimulates transcription of heat shock-responsive genes. Nucleic Acids Res 2019; 47:2840-2855. [PMID: 30649429 PMCID: PMC6451099 DOI: 10.1093/nar/gkz006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/27/2018] [Accepted: 01/03/2019] [Indexed: 01/02/2023] Open
Abstract
RNF20/40 E3 ubiquitin ligase-mediated histone H2B monoubiquitylation plays important roles in many cellular processes, including transcriptional regulation. However, the multiple defects observed in RNF20-depleted cells suggest additional ubiquitylation targets of RNF20/40 beyond histone H2B. Here, using biochemically defined assays employing purified factors and cell-based analyses, we demonstrate that RNF20/40, in conjunction with its cognate E2 ubiquitin-conjugating enzyme RAD6, monoubiquitylates lysine 381 of eEF1BδL, a heat shock transcription factor. Notably, monoubiquitylation of eEF1BδL increases eEF1BδL accumulation and potentiates recruitment of p-TEFb to the promoter regions of heat shock-responsive genes, leading to enhanced transcription of these genes. We further demonstrate that cooperative physical interactions among eEF1BδL, RNF20/40, and HSF1 synergistically promote expression of heat shock-responsive genes. In addition to identifying eEF1BδL as a novel ubiquitylation target of RNF20/40 and elucidating its function, we provide a molecular mechanism for the cooperative function of distinct transcription factors in heat shock-responsive gene transcription.
Collapse
Affiliation(s)
- Suna In
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| | - Yong-In Kim
- Center for Bioanalysis, Korea Research Institute of Standards and Science, Daejeon 34113, South Korea
| | - J Eugene Lee
- Center for Bioanalysis, Korea Research Institute of Standards and Science, Daejeon 34113, South Korea
| | - Jaehoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| |
Collapse
|
28
|
Gressel S, Schwalb B, Cramer P. The pause-initiation limit restricts transcription activation in human cells. Nat Commun 2019; 10:3603. [PMID: 31399571 PMCID: PMC6689055 DOI: 10.1038/s41467-019-11536-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 07/18/2019] [Indexed: 01/01/2023] Open
Abstract
Eukaryotic gene transcription is often controlled at the level of RNA polymerase II (Pol II) pausing in the promoter-proximal region. Pausing Pol II limits the frequency of transcription initiation ('pause-initiation limit'), predicting that the pause duration must be decreased for transcriptional activation. To test this prediction, we conduct a genome-wide kinetic analysis of the heat shock response in human cells. We show that the pause-initiation limit restricts transcriptional activation at most genes. Gene activation generally requires the activity of the P-TEFb kinase CDK9, which decreases the duration of Pol II pausing and thereby enables an increase in the productive initiation frequency. The transcription of enhancer elements is generally not pause limited and can be activated without CDK9 activity. Our results define the kinetics of Pol II transcriptional regulation in human cells at all gene classes during a natural transcription response.
Collapse
Affiliation(s)
- Saskia Gressel
- Department of Molecular Biology, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077, Göttingen, Germany
| | - Björn Schwalb
- Department of Molecular Biology, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077, Göttingen, Germany.
| | - Patrick Cramer
- Department of Molecular Biology, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077, Göttingen, Germany.
| |
Collapse
|
29
|
Abstract
Proteotoxic stress, that is, stress caused by protein misfolding and aggregation, triggers the rapid and global reprogramming of transcription at genes and enhancers. Genome-wide assays that track transcriptionally engaged RNA polymerase II (Pol II) at nucleotide resolution have provided key insights into the underlying molecular mechanisms that regulate transcriptional responses to stress. In addition, recent kinetic analyses of transcriptional control under heat stress have shown how cells 'prewire' and rapidly execute genome-wide changes in transcription while concurrently becoming poised for recovery. The regulation of Pol II at genes and enhancers in response to heat stress is coupled to chromatin modification and compartmentalization, as well as to co-transcriptional RNA processing. These mechanistic features seem to apply broadly to other coordinated genome-regulatory responses.
Collapse
|
30
|
Abstract
In this review, Core et al. discuss the recent advances in our understanding of the early steps in Pol II transcription, highlighting the events and factors involved in the establishment and release of paused Pol II. They also discuss a number of unanswered questions about the regulation and function of Pol II pausing. Precise spatio–temporal control of gene activity is essential for organismal development, growth, and survival in a changing environment. Decisive steps in gene regulation involve the pausing of RNA polymerase II (Pol II) in early elongation, and the controlled release of paused polymerase into productive RNA synthesis. Here we describe the factors that enable pausing and the events that trigger Pol II release into the gene. We also discuss open questions in the field concerning the stability of paused Pol II, nucleosomes as obstacles to elongation, and potential roles of pausing in defining the precision and dynamics of gene expression.
Collapse
Affiliation(s)
- Leighton Core
- Department of Molecular and Cell Biology, Institute of Systems Genomics, University of Connecticut, Storrs, Connecticut 06269, USA
| | - Karen Adelman
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| |
Collapse
|
31
|
Bunch H, Choe H, Kim J, Jo DS, Jeon S, Lee S, Cho DH, Kang K. P-TEFb Regulates Transcriptional Activation in Non-coding RNA Genes. Front Genet 2019; 10:342. [PMID: 31068966 PMCID: PMC6491683 DOI: 10.3389/fgene.2019.00342] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 03/29/2019] [Indexed: 01/16/2023] Open
Abstract
Many non-coding RNAs (ncRNAs) serve as regulatory molecules in various physiological pathways, including gene expression in mammalian cells. Distinct from protein-coding RNA expression, ncRNA expression is regulated solely by transcription and RNA processing/stability. It is thus important to understand transcriptional regulation in ncRNA genes but is yet to be known completely. Previously, we identified that a subset of mammalian ncRNA genes is transcriptionally regulated by RNA polymerase II (Pol II) promoter-proximal pausing and in a tissue-specific manner. In this study, human ncRNA genes that are expressed in the early G1 phase, termed immediate early ncRNA genes, were monitored to assess the function of positive transcription elongation factor b (P-TEFb), a master Pol II pausing regulator for protein-coding genes, in ncRNA transcription. Our findings indicate that the expression of many ncRNA genes is induced in the G0–G1 transition and regulated by P-TEFb. Interestingly, a biphasic characteristic of P-TEFb-dependent transcription of serum responsive ncRNA genes was observed: Pol II carboxyl-terminal domain phosphorylated at serine 2 (S2) was largely increased in the transcription start site (TSS, -300 to +300) whereas overall, it was decreased in the gene body (GB, > +350) upon chemical inhibition of P-TEFb. In addition, the three representative, immediate early ncRNAs, whose expression is dependent on P-TEFb, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), nuclear enriched abundant transcript 1 (NEAT1), and X-inactive specific transcript (XIST), were further analyzed for determining P-TEFb association. Taken together, our data suggest that transcriptional activation of many human ncRNAs utilizes the pausing and releasing of Pol II, and that the regulatory mechanism of transcriptional elongation in these genes requires the function of P-TEFb. Furthermore, we propose that ncRNA and mRNA transcription are regulated by similar mechanisms while P-TEFb inhibition unexpectedly increases S2 Pol II phosphorylation in the TSSs in many ncRNA genes. One Sentence Summary: P-TEFb regulates Pol II phosphorylation for transcriptional activation in many stimulus-inducible ncRNA genes.
Collapse
Affiliation(s)
- Heeyoun Bunch
- Department of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu, South Korea
| | - Hyeseung Choe
- Department of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu, South Korea
| | - Jongbum Kim
- Department of Transcriptome & Epigenome, Macrogen Incorporated, Seoul, South Korea
| | - Doo Sin Jo
- Institute of Life Science and Biotechnology, College of Natural Science, Kyungpook National University, Daegu, South Korea
| | - Soyeon Jeon
- Department of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu, South Korea
| | - Sanghwa Lee
- Department of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu, South Korea
| | - Dong-Hyung Cho
- Department of Life Science, College of Natural Science, Kyungpook National University, Daegu, South Korea
| | - Keunsoo Kang
- Department of Microbiology, College of Natural Sciences, Dankook University, Cheonan, South Korea
| |
Collapse
|
32
|
Carew NT, Nelson AM, Liang Z, Smith SM, Milcarek C. Linking Endoplasmic Reticular Stress and Alternative Splicing. Int J Mol Sci 2018; 19:ijms19123919. [PMID: 30544499 PMCID: PMC6321306 DOI: 10.3390/ijms19123919] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/04/2018] [Accepted: 12/05/2018] [Indexed: 12/16/2022] Open
Abstract
RNA splicing patterns in antibody-secreting cells are shaped by endoplasmic reticulum stress, ELL2 (eleven-nineteen lysine-rich leukemia gene 2) induction, and changes in the levels of snRNAs. Endoplasmic reticulum stress induces the unfolded protein response comprising a highly conserved set of genes crucial for cell survival; among these is Ire1, whose auto-phosphorylation drives it to acquire a regulated mRNA decay activity. The mRNA-modifying function of phosphorylated Ire1 non-canonically splices Xbp1 mRNA and yet degrades other cellular mRNAs with related motifs. Naïve splenic B cells will activate Ire1 phosphorylation early on after lipopolysaccharide (LPS) stimulation, within 18 h; large-scale changes in mRNA content and splicing patterns result. Inhibition of the mRNA-degradation function of Ire1 is correlated with further differences in the splicing patterns and a reduction in the mRNA factors for snRNA transcription. Some of the >4000 splicing changes seen at 18 h after LPS stimulation persist into the late stages of antibody secretion, up to 72 h. Meanwhile some early splicing changes are supplanted by new splicing changes introduced by the up-regulation of ELL2, a transcription elongation factor. ELL2 is necessary for immunoglobulin secretion and does this by changing mRNA processing patterns of immunoglobulin heavy chain and >5000 other genes.
Collapse
Affiliation(s)
- Nolan T Carew
- School of Medicine, Department of Immunology, University of Pittsburgh, E1059 Biomedical Science Tower, Pittsburgh, PA 15261, USA.
| | - Ashley M Nelson
- School of Medicine, Department of Immunology, University of Pittsburgh, E1059 Biomedical Science Tower, Pittsburgh, PA 15261, USA.
| | - Zhitao Liang
- School of Medicine, Department of Immunology, University of Pittsburgh, E1059 Biomedical Science Tower, Pittsburgh, PA 15261, USA.
| | - Sage M Smith
- School of Medicine, Department of Immunology, University of Pittsburgh, E1059 Biomedical Science Tower, Pittsburgh, PA 15261, USA.
| | - Christine Milcarek
- School of Medicine, Department of Immunology, University of Pittsburgh, E1059 Biomedical Science Tower, Pittsburgh, PA 15261, USA.
| |
Collapse
|
33
|
Ali A, Biswas A, Pal M. HSF1 mediated TNF‐α production during proteotoxic stress response pioneers proinflammatory signal in human cells. FASEB J 2018; 33:2621-2635. [DOI: 10.1096/fj.201801482r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Asif Ali
- Division of Molecular MedicineBose InstituteKolkataIndia
| | | | - Mahadeb Pal
- Division of Molecular MedicineBose InstituteKolkataIndia
| |
Collapse
|
34
|
Abstract
Cyclin-dependent kinase 9 (CDK9) is critical for RNA Polymerase II (Pol II) transcription initiation, elongation, and termination in several key biological processes including development, differentiation, and cell fate responses. A broad range of diseases are characterized by CDK9 malfunction, illustrating its importance in maintaining transcriptional homeostasis in basal- and signal-regulated conditions. Here we provide a historical recount of CDK9 discovery and the current models suggesting CDK9 is a central hub necessary for proper execution of different steps in the transcription cycle. Finally, we discuss the current therapeutic strategies to treat CDK9 malfunction in several disease states. Abbreviations: CDK: Cyclin-dependent kinase; Pol II: RNA Polymerase II; PIC: Pre-initiation Complex; TFIIH: Transcription Factor-II H; snoRNA: small nucleolar RNA; CycT: CyclinT1/T2; P-TEFb: Positive Transcription Elongation Factor Complex; snRNP: small nuclear ribonucleo-protein; HEXIM: Hexamethylene Bis-acetamide-inducible Protein 1/2; LARP7: La-related Protein 7; MePCE: Methylphosphate Capping Enzyme; HIV: human immunodeficiency virus; TAT: trans-activator of transcription; TAR: Trans-activation response element; Hsp70: Heat Shock Protein 70; Hsp90/Cdc37: Hsp90- Hsp90 co-chaperone Cdc37; DSIF: DRB Sensitivity Inducing Factor; NELF: Negative Elongation Factor; CPSF: cleavage and polyadenylation-specific factor; CSTF: cleavage-stimulatory factor; eRNA: enhancer RNA; BRD4: Bromodomain-containing protein 4; JMJD6: Jumonji C-domain-containing protein 6; SEC: Super Elongation Complex; ELL: eleven-nineteen Lys-rich leukemia; ENL: eleven-nineteen leukemia; MLL: mixed lineage leukemia; BEC: BRD4-containing Elongation Complex; SEC-L2/L3: SEC-like complexes; KAP1: Kruppel-associated box-protein 1; KEC: KAP1-7SK Elongation Complex; DRB: Dichloro-1-ß-D-Ribofuranosylbenzimidazole; H2Bub1: H2B mono-ubiquitination; KM: KM05382; PP1: Protein Phosphatase 1; CDK9i: CDK9 inhibitor; SHAPE: Selective 2'-hydroxyl acylation analyzed by primer extension; TE: Typical enhancer; SE : Super enhancer.
Collapse
Affiliation(s)
- Curtis W Bacon
- a Biological Chemistry Graduate Program , The University of Texas Southwestern Medical Center , Dallas, TX , USA
| | - Iván D'Orso
- b Department of Microbiology , The University of Texas Southwestern Medical Center , Dallas , TX , USA
| |
Collapse
|
35
|
Haberle V, Stark A. Eukaryotic core promoters and the functional basis of transcription initiation. Nat Rev Mol Cell Biol 2018; 19:621-637. [PMID: 29946135 PMCID: PMC6205604 DOI: 10.1038/s41580-018-0028-8] [Citation(s) in RCA: 399] [Impact Index Per Article: 66.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
RNA polymerase II (Pol II) core promoters are specialized DNA sequences at transcription start sites of protein-coding and non-coding genes that support the assembly of the transcription machinery and transcription initiation. They enable the highly regulated transcription of genes by selectively integrating regulatory cues from distal enhancers and their associated regulatory proteins. In this Review, we discuss the defining properties of gene core promoters, including their sequence features, chromatin architecture and transcription initiation patterns. We provide an overview of molecular mechanisms underlying the function and regulation of core promoters and their emerging functional diversity, which defines distinct transcription programmes. On the basis of the established properties of gene core promoters, we discuss transcription start sites within enhancers and integrate recent results obtained from dedicated functional assays to propose a functional model of transcription initiation. This model can explain the nature and function of transcription initiation at gene starts and at enhancers and can explain the different roles of core promoters, of Pol II and its associated factors and of the activating cues provided by enhancers and the transcription factors and cofactors they recruit.
Collapse
Affiliation(s)
- Vanja Haberle
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Alexander Stark
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria.
- Medical University of Vienna, Vienna Biocenter (VBC), Vienna, Austria.
| |
Collapse
|
36
|
Interferon stimulation creates chromatin marks and establishes transcriptional memory. Proc Natl Acad Sci U S A 2018; 115:E9162-E9171. [PMID: 30201712 DOI: 10.1073/pnas.1720930115] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Epigenetic memory for signal-dependent transcription has remained elusive. So far, the concept of epigenetic memory has been largely limited to cell-autonomous, preprogrammed processes such as development and metabolism. Here we show that IFNβ stimulation creates transcriptional memory in fibroblasts, conferring faster and greater transcription upon restimulation. The memory was inherited through multiple cell divisions and led to improved antiviral protection. Of ∼2,000 IFNβ-stimulated genes (ISGs), about half exhibited memory, which we define as memory ISGs. The rest, designated nonmemory ISGs, did not show memory. Surprisingly, mechanistic analysis showed that IFN memory was not due to enhanced IFN signaling or retention of transcription factors on the ISGs. We demonstrated that this memory was attributed to accelerated recruitment of RNA polymerase II and transcription/chromatin factors, which coincided with acquisition of the histone H3.3 and H3K36me3 chromatin marks on memory ISGs. Similar memory was observed in bone marrow macrophages after IFNγ stimulation, suggesting that IFN stimulation modifies the shape of the innate immune response. Together, external signals can establish epigenetic memory in mammalian cells that imparts lasting adaptive performance upon various somatic cells.
Collapse
|
37
|
Choi A, Wang M, Hrizo S, Buckley MS. Visualizing cellular stress: A hypothesis-driven confocal laboratory exercise to identify compounds that activate heat shock factor binding at Hsp70 loci. BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION : A BIMONTHLY PUBLICATION OF THE INTERNATIONAL UNION OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 46:445-452. [PMID: 30204283 DOI: 10.1002/bmb.21163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 06/11/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
Exposure of organisms to high temperatures and various chemical and physical stressors can cause protein misfolding and aggregation. In turn, this can disrupt the functions of proteins, threatening both development and homeostasis. To overcome this, cells can initiate the highly conserved heat shock (HS) stress response pathway. In eukaryotes, this is a coordinated cellular response, in which the master HS activator, heat shock factor (HSF), is rapidly recruited to the HS protein genes, and triggers the recruitment of additional coactivator proteins that facilitate gene expression. This results in the production of HS proteins that function as nuclear and cytosolic molecular chaperones, to promote refolding of proteins and prevent aggregation and increase protein degradation pathways. Here, we describe a laboratory exercise in which students visualize and quantify Green Fluorescent Protein (GFP)-tagged HSF binding to the HS protein genes in living Drosophila salivary gland nuclei as an output of chemically induced protein misfolding. Students are assigned an array of chemicals, and using the scientific literature, predict impacts of these chemicals on protein folding. Students then test the effects of their chemicals by measuring GFP-tagged HSF binding to the HS genes in salivary glands using confocal microscopy. Designed for junior and senior level students in a cell/molecular biology course, this is a two-part lab, in which student work closely with an instructor to help familiarize them with developing hypotheses supported by scientific literature and testing these hypotheses by quantitating the levels of GFP-HSF binding, using confocal microscopy of living Drosophila cells. © 2018 International Union of Biochemistry and Molecular Biology, 46(5):445-452, 2018.
Collapse
Affiliation(s)
- Annette Choi
- Department of Biology, Slippery Rock University, Slippery Rock, Pennsylvania, 16057
| | - Mengqi Wang
- Department of Biology, Slippery Rock University, Slippery Rock, Pennsylvania, 16057
| | - Stacy Hrizo
- Department of Biology, Slippery Rock University, Slippery Rock, Pennsylvania, 16057
- Department of Pharmacology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261
| | - Martin S Buckley
- Department of Biology, Slippery Rock University, Slippery Rock, Pennsylvania, 16057
- Department of Pharmacology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261
| |
Collapse
|
38
|
Poly(ADP-Ribose) Polymerase 1 Promotes the Human Heat Shock Response by Facilitating Heat Shock Transcription Factor 1 Binding to DNA. Mol Cell Biol 2018; 38:MCB.00051-18. [PMID: 29661921 DOI: 10.1128/mcb.00051-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 04/11/2018] [Indexed: 01/09/2023] Open
Abstract
The heat shock response (HSR) is characterized by the rapid and robust induction of heat shock proteins (HSPs), including HSP70, in response to heat shock and is regulated by heat shock transcription factor 1 (HSF1) in mammalian cells. Poly(ADP-ribose) polymerase 1 (PARP1), which can form a complex with HSF1 through the scaffold protein PARP13, has been suggested to be involved in the HSR. However, its effects on and the regulatory mechanisms of the HSR are not well understood. Here we show that prior to heat shock, the HSF1-PARP13-PARP1 complex binds to the HSP70 promoter. In response to heat shock, activated and auto-PARylated PARP1 dissociates from HSF1-PARP13 and is redistributed throughout the HSP70 locus. Remarkably, chromatin in the HSP70 promoter is initially PARylated at high levels and decondensed, whereas chromatin in the gene body is moderately PARylated afterwards. Activated HSF1 then binds to the promoter efficiently and promotes the HSR. Chromatin PARylation and HSF1 binding to the promoter are also facilitated by the phosphorylation-dependent dissociation of PARP13. Furthermore, the HSR and proteostasis capacity are reduced by pretreatment with genotoxic stresses, which disrupt the ternary complex. These results illuminate one of the priming mechanisms of the HSR that facilitates the binding of HSF1 to DNA during heat shock.
Collapse
|
39
|
Gene expression regulation by heat-shock proteins: the cardinal roles of HSF1 and Hsp90. Biochem Soc Trans 2017; 46:51-65. [PMID: 29273620 DOI: 10.1042/bst20170335] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 10/21/2017] [Accepted: 10/27/2017] [Indexed: 12/31/2022]
Abstract
The ability to permit gene expression is managed by a set of relatively well known regulatory mechanisms. Nonetheless, this property can also be acquired during a life span as a consequence of environmental stimuli. Interestingly, some acquired information can be passed to the next generation of individuals without modifying gene information, but instead by the manner in which cells read and process such information. Molecular chaperones are classically related to the proper preservation of protein folding and anti-aggregation properties, but one of them, heat-shock protein 90 (Hsp90), is a refined sensor of protein function facilitating the biological activity of properly folded client proteins that already have a preserved tertiary structure. Interestingly, Hsp90 can also function as a critical switch able to regulate biological responses due to its association with key client proteins such as histone deacetylases or DNA methylases. Thus, a growing amount of evidence has connected the action of Hsp90 to post-translational modifications of soluble nuclear factors, DNA, and histones, which epigenetically affect gene expression upon the onset of an unfriendly environment. This response is commanded by the activation of the transcription factor heat-shock factor 1 (HSF1). Even though numerous stresses of diverse nature are known to trigger the stress response by activation of HSF1, it is still unknown whether there are different types of molecular sensors for each type of stimulus. In the present review, we will discuss various aspects of the regulatory action of HSF1 and Hsp90 on transcriptional regulation, and how this regulation may affect genetic assimilation mechanisms and the health of individuals.
Collapse
|
40
|
Pereira A, Paro R. Pho dynamically interacts with Spt5 to facilitate transcriptional switches at the hsp70 locus. Epigenetics Chromatin 2017; 10:57. [PMID: 29208012 PMCID: PMC5718073 DOI: 10.1186/s13072-017-0166-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 11/29/2017] [Indexed: 11/10/2022] Open
Abstract
Background Numerous target genes of the Polycomb group (PcG) are transiently activated by a stimulus and subsequently repressed. However, mechanisms by which PcG proteins regulate such target genes remain elusive. Results We employed the heat shock-responsive hsp70 locus in Drosophila to study the chromatin dynamics of PRC1 and its interplay with known regulators of the locus before, during and after heat shock. We detected mutually exclusive binding patterns for HSF and PRC1 at the hsp70 locus. We found that Pleiohomeotic (Pho), a DNA-binding PcG member, dynamically interacts with Spt5, an elongation factor. The dynamic interaction switch between Pho and Spt5 is triggered by the recruitment of HSF to chromatin. Mutation in the protein–protein interaction domain (REPO domain) of Pho interferes with the dynamics of its interaction with Spt5. The transcriptional kinetics of the heat shock response is negatively affected by a mutation in the REPO domain of Pho. Conclusions We propose that a dynamic interaction switch between PcG proteins and an elongation factor enables stress-inducible genes to efficiently switch between ON/OFF states in the presence/absence of the activating stimulus. Electronic supplementary material The online version of this article (10.1186/s13072-017-0166-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Allwyn Pereira
- Department of Biosystems Science and Engineering, ETH Zurich, 4058, Basel, Switzerland
| | - Renato Paro
- Department of Biosystems Science and Engineering, ETH Zurich, 4058, Basel, Switzerland. .,Faculty of Sciences, University of Basel, 4056, Basel, Switzerland.
| |
Collapse
|
41
|
RNA polymerase II pausing and transcriptional regulation of the HSP70 expression. Eur J Cell Biol 2017; 96:739-745. [DOI: 10.1016/j.ejcb.2017.09.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Revised: 08/16/2017] [Accepted: 09/25/2017] [Indexed: 12/20/2022] Open
|
42
|
Dukler N, Booth GT, Huang YF, Tippens N, Waters CT, Danko CG, Lis JT, Siepel A. Nascent RNA sequencing reveals a dynamic global transcriptional response at genes and enhancers to the natural medicinal compound celastrol. Genome Res 2017; 27:1816-1829. [PMID: 29025894 PMCID: PMC5668940 DOI: 10.1101/gr.222935.117] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 09/13/2017] [Indexed: 12/16/2022]
Abstract
Most studies of responses to transcriptional stimuli measure changes in cellular mRNA concentrations. By sequencing nascent RNA instead, it is possible to detect changes in transcription in minutes rather than hours and thereby distinguish primary from secondary responses to regulatory signals. Here, we describe the use of PRO-seq to characterize the immediate transcriptional response in human cells to celastrol, a compound derived from traditional Chinese medicine that has potent anti-inflammatory, tumor-inhibitory, and obesity-controlling effects. Celastrol is known to elicit a cellular stress response resembling the response to heat shock, but the transcriptional basis of this response remains unclear. Our analysis of PRO-seq data for K562 cells reveals dramatic transcriptional effects soon after celastrol treatment at a broad collection of both coding and noncoding transcription units. This transcriptional response occurred in two major waves, one within 10 min, and a second 40-60 min after treatment. Transcriptional activity was generally repressed by celastrol, but one distinct group of genes, enriched for roles in the heat shock response, displayed strong activation. Using a regression approach, we identified key transcription factors that appear to drive these transcriptional responses, including members of the E2F and RFX families. We also found sequence-based evidence that particular transcription factors drive the activation of enhancers. We observed increased polymerase pausing at both genes and enhancers, suggesting that pause release may be widely inhibited during the celastrol response. Our study demonstrates that a careful analysis of PRO-seq time-course data can disentangle key aspects of a complex transcriptional response, and it provides new insights into the activity of a powerful pharmacological agent.
Collapse
Affiliation(s)
- Noah Dukler
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
- Tri-Institutional Training Program in Computational Biology and Medicine, New York, New York 10065, USA
| | - Gregory T Booth
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850, USA
| | - Yi-Fei Huang
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
| | - Nathaniel Tippens
- Tri-Institutional Training Program in Computational Biology and Medicine, New York, New York 10065, USA
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850, USA
| | - Colin T Waters
- Program in Biological and Biomedical Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Charles G Danko
- Baker Institute for Animal Health, Cornell University, Ithaca, New York 14850, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14850, USA
| | - Adam Siepel
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
| |
Collapse
|
43
|
Bunch H. Gene regulation of mammalian long non-coding RNA. Mol Genet Genomics 2017; 293:1-15. [PMID: 28894972 DOI: 10.1007/s00438-017-1370-9] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 09/07/2017] [Indexed: 12/14/2022]
Abstract
RNA polymerase II (Pol II) transcribes two classes of RNAs, protein-coding and non-protein-coding (ncRNA) genes. ncRNAs are also synthesized by RNA polymerases I and III (Pol I and III). In humans, the number of ncRNA genes exceeds more than twice that of protein-coding genes. However, the history of studying Pol II-synthesized ncRNA is relatively short. Since early 2000s, important biological and pathological functions of these ncRNA genes have begun to be discovered and intensively studied. And transcription mechanisms of long non-coding RNA (lncRNA) have been recently reported. Transcription of lncRNAs utilizes some transcription factors and mechanisms shared in that of protein-coding genes. In addition, tissue specificity in lncRNA gene expression has been shown. LncRNAs play essential roles in regulating the expression of neighboring or distal genes through different mechanisms. This leads to the implication of lncRNAs in a wide variety of biological pathways and pathological development. In this review, the newly discovered transcription mechanisms, characteristics, and functions of lncRNA are discussed.
Collapse
Affiliation(s)
- Heeyoun Bunch
- School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Agriculture & Life Sciences Building 1, Room 207, 80 Dae-Hak Ro, Daegu, Republic of Korea.
| |
Collapse
|
44
|
Vihervaara A, Mahat DB, Guertin MJ, Chu T, Danko CG, Lis JT, Sistonen L. Transcriptional response to stress is pre-wired by promoter and enhancer architecture. Nat Commun 2017; 8:255. [PMID: 28811569 PMCID: PMC5557961 DOI: 10.1038/s41467-017-00151-0] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 06/05/2017] [Indexed: 12/29/2022] Open
Abstract
Programs of gene expression are executed by a battery of transcription factors that coordinate divergent transcription from a pair of tightly linked core initiation regions of promoters and enhancers. Here, to investigate how divergent transcription is reprogrammed upon stress, we measured nascent RNA synthesis at nucleotide-resolution, and profiled histone H4 acetylation in human cells. Our results globally show that the release of promoter-proximal paused RNA polymerase into elongation functions as a critical switch at which a gene’s response to stress is determined. Highly transcribed and highly inducible genes display strong transcriptional directionality and selective assembly of general transcription factors on the core sense promoter. Heat-induced transcription at enhancers, instead, correlates with prior binding of cell-type, sequence-specific transcription factors. Activated Heat Shock Factor 1 (HSF1) binds to transcription-primed promoters and enhancers, and CTCF-occupied, non-transcribed chromatin. These results reveal chromatin architectural features that orient transcription at divergent regulatory elements and prime transcriptional responses genome-wide. Heat Shock Factor 1 (HSF1) is a regulator of stress-induced transcription. Here, the authors investigate changes to transcription and chromatin organization upon stress and find that activated HSF1 binds to transcription-primed promoters and enhancers, and to CTCF occupied, untranscribed chromatin.
Collapse
Affiliation(s)
- Anniina Vihervaara
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, Turku, 20520, Finland.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, 14853, USA
| | - Dig Bijay Mahat
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, 14853, USA
| | - Michael J Guertin
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia, 22908, USA
| | - Tinyi Chu
- Department of Biomedical Sciences, The Baker Institute for Animal Health, Cornell University, Ithaca, New York, 14853, USA.,Graduate Field of Computational Biology, Cornell University, Ithaca, New York, 14853, USA
| | - Charles G Danko
- Department of Biomedical Sciences, The Baker Institute for Animal Health, Cornell University, Ithaca, New York, 14853, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, 14853, USA.
| | - Lea Sistonen
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, Turku, 20520, Finland.
| |
Collapse
|
45
|
Dynamic Change of Transcription Pausing through Modulating NELF Protein Stability Regulates Granulocytic Differentiation. Blood Adv 2017; 1:1358-1367. [PMID: 28868519 DOI: 10.1182/bloodadvances.2017008383] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The NELF complex is a metazoan-specific factor essential for establishing transcription pausing. Although NELF has been implicated in cell fate regulation, the cellular regulation of NELF and its intrinsic role in specific lineage differentiation remains largely unknown. Using mammalian hematopoietic differentiation as a model system, here we identified a dynamic change of NELF-mediated transcription pausing as a novel mechanism regulating hematopoietic differentiation. We found a sharp decrease of NELF protein abundance upon granulocytic differentiation and a subsequent genome-wide reduction of transcription pausing. This loss of pausing coincides with activation of granulocyte-affiliated genes and diminished expression of progenitor markers. Functional studies revealed that sustained expression of NELF inhibits granulocytic differentiation, whereas NELF depletion in progenitor cells leads to premature differentiation towards the granulocytic lineage. Our results thus uncover a previously unrecognized regulation of transcription pausing by modulating NELF protein abundance to control cellular differentiation.
Collapse
|
46
|
Lu X, Batugedara G, Lee M, Prudhomme J, Bunnik EM, Le Roch K. Nascent RNA sequencing reveals mechanisms of gene regulation in the human malaria parasite Plasmodium falciparum. Nucleic Acids Res 2017; 45:7825-7840. [PMID: 28531310 PMCID: PMC5737683 DOI: 10.1093/nar/gkx464] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/08/2017] [Accepted: 05/10/2017] [Indexed: 12/18/2022] Open
Abstract
Gene expression in Plasmodium falciparum is tightly regulated to ensure successful propagation of the parasite throughout its complex life cycle. The earliest transcriptomics studies in P. falciparum suggested a cascade of transcriptional activity over the course of the 48-hour intraerythrocytic developmental cycle (IDC); however, the just-in-time transcriptional model has recently been challenged by findings that show the importance of post-transcriptional regulation. To further explore the role of transcriptional regulation, we performed the first genome-wide nascent RNA profiling in P. falciparum. Our findings indicate that the majority of genes are transcribed simultaneously during the trophozoite stage of the IDC and that only a small subset of genes is subject to differential transcriptional timing. RNA polymerase II is engaged with promoter regions prior to this transcriptional burst, suggesting that Pol II pausing plays a dominant role in gene regulation. In addition, we found that the overall transcriptional program during gametocyte differentiation is surprisingly similar to the IDC, with the exception of relatively small subsets of genes. Results from this study suggest that further characterization of the molecular players that regulate stage-specific gene expression and Pol II pausing will contribute to our continuous search for novel antimalarial drug targets.
Collapse
MESH Headings
- Animals
- Epigenesis, Genetic
- Gene Expression Profiling
- Gene Expression Regulation, Developmental
- Genes, Protozoan
- Humans
- Malaria, Falciparum/blood
- Malaria, Falciparum/parasitology
- Plasmodium falciparum/genetics
- Plasmodium falciparum/growth & development
- Plasmodium falciparum/pathogenicity
- Promoter Regions, Genetic
- RNA Polymerase II/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Protozoan/genetics
- RNA, Protozoan/metabolism
- Sequence Analysis, RNA
- Transcription, Genetic
Collapse
Affiliation(s)
- Xueqing Maggie Lu
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA
| | - Gayani Batugedara
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA
| | - Michael Lee
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA
| | - Jacques Prudhomme
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA
| | - Evelien M. Bunnik
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA
- Department of Microbiology, Immunology and Molecular Genetics, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Karine G. Le Roch
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA
| |
Collapse
|
47
|
Krebs AR, Imanci D, Hoerner L, Gaidatzis D, Burger L, Schübeler D. Genome-wide Single-Molecule Footprinting Reveals High RNA Polymerase II Turnover at Paused Promoters. Mol Cell 2017; 67:411-422.e4. [PMID: 28735898 PMCID: PMC5548954 DOI: 10.1016/j.molcel.2017.06.027] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 05/22/2017] [Accepted: 06/22/2017] [Indexed: 11/19/2022]
Abstract
Transcription initiation entails chromatin opening followed by pre-initiation complex formation and RNA polymerase II recruitment. Subsequent polymerase elongation requires additional signals, resulting in increased residence time downstream of the start site, a phenomenon referred to as pausing. Here, we harnessed single-molecule footprinting to quantify distinct steps of initiation in vivo throughout the Drosophila genome. This identifies the impact of promoter structure on initiation dynamics in relation to nucleosomal occupancy. Additionally, perturbation of transcriptional initiation reveals an unexpectedly high turnover of polymerases at paused promoters-an observation confirmed at the level of nascent RNAs. These observations argue that absence of elongation is largely caused by premature termination rather than by stable polymerase stalling. In support of this non-processive model, we observe that induction of the paused heat shock promoter depends on continuous initiation. Our study provides a framework to quantify protein binding at single-molecule resolution and refines concepts of transcriptional pausing.
Collapse
Affiliation(s)
- Arnaud R Krebs
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland.
| | - Dilek Imanci
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Leslie Hoerner
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Dimos Gaidatzis
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; Swiss Institute of Bioinformatics, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Lukas Burger
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; Swiss Institute of Bioinformatics, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Dirk Schübeler
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; University of Basel, Faculty of Sciences, Petersplatz 1, 4001 Basel, Switzerland.
| |
Collapse
|
48
|
Yang H, Basquin D, Pauli D, Oliver B. Drosophila melanogaster positive transcriptional elongation factors regulate metabolic and sex-biased expression in adults. BMC Genomics 2017; 18:384. [PMID: 28521739 PMCID: PMC5436443 DOI: 10.1186/s12864-017-3755-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 05/03/2017] [Indexed: 11/22/2022] Open
Abstract
Background Transcriptional elongation is a generic function, but is also regulated to allow rapid transcription responses. Following relatively long initiation and promoter clearance, RNA polymerase II can pause and then rapidly elongate following recruitment of positive elongation factors. Multiple elongation complexes exist, but the role of specific components in adult Drosophila is underexplored. Results We conducted RNA-seq experiments to analyze the effect of RNAi knockdown of Suppressor of Triplolethal and lilliputian. We similarly analyzed the effect of expressing a dominant negative Cyclin-dependent kinase 9 allele. We observed that almost half of the genes expressed in adults showed reduced expression, supporting a broad role for the three tested genes in steady-state transcript abundance. Expression profiles following lilliputian and Suppressor of Triplolethal RNAi were nearly identical raising the possibility that they are obligatory co-factors. Genes showing reduced expression due to these RNAi treatments were short and enriched for genes encoding metabolic or enzymatic functions. The dominant-negative Cyclin-dependent kinase 9 profiles showed both overlapping and specific differential expression, suggesting involvement in multiple complexes. We also observed hundreds of genes with sex-biased differential expression following treatment. Conclusion Transcriptional profiles suggest that Lilliputian and Suppressor of Triplolethal are obligatory cofactors in the adult and that they can also function with Cyclin-dependent kinase 9 at a subset of loci. Our results suggest that transcriptional elongation control is especially important for rapidly expressed genes to support digestion and metabolism, many of which have sex-biased function. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3755-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Haiwang Yang
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 50 South Drive, Bethesda, MD, 20892, USA.
| | - Denis Basquin
- Department of Genetics & Evolution, Sciences III, University of Geneva, Boulevard d'Yvoy 4, CH 1205, Geneva, Switzerland
| | - Daniel Pauli
- Department of Genetics & Evolution, Sciences III, University of Geneva, Boulevard d'Yvoy 4, CH 1205, Geneva, Switzerland
| | - Brian Oliver
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 50 South Drive, Bethesda, MD, 20892, USA
| |
Collapse
|
49
|
Niskanen EA, Palvimo JJ. Chromatin SUMOylation in heat stress: To protect, pause and organise?: SUMO stress response on chromatin. Bioessays 2017; 39. [PMID: 28440894 DOI: 10.1002/bies.201600263] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Post-translational modifications, e.g. SUMO modifications (SUMOylation), provide a mechanism for swiftly changing a protein's activity. Various stress conditions trigger a SUMO stress response (SSR) - a stress-induced rapid change in the conjugation of SUMO to multiple proteins, which predominantly targets nuclear proteins. The SSR has been postulated to protect stressed cells by preserving the functionality of crucial proteins. However, it is unclear how it exerts its protective functions. Interestingly, heat stress (HS) increases SUMOylation of proteins at active promoters and enhancers. In promoters, HS-induced SUMOylation correlates with gene transcription and stress-induced RNA polymerase II (Pol2) pausing. Conversely, a disappearance of SUMOylation in HS occurs at chromatin anchor points that maintain chromatin-looping structures and the spatial organisation of chromatin. In reviewing the literature, we hypothesise that the SSR regulates Pol2 pausing by modulating the interactions of pausing-regulating proteins, whereas deSUMOylation alters the function of chromatin anchors.
Collapse
Affiliation(s)
- Einari A Niskanen
- University of Eastern Finland, Institute of Biomedicine, Kuopio, Finland
| | - Jorma J Palvimo
- University of Eastern Finland, Institute of Biomedicine, Kuopio, Finland
| |
Collapse
|
50
|
Kuzmina A, Krasnopolsky S, Taube R. Super elongation complex promotes early HIV transcription and its function is modulated by P-TEFb. Transcription 2017; 8:133-149. [PMID: 28340332 DOI: 10.1080/21541264.2017.1295831] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Early work on the control of transcription of the human immunodeficiency virus (HIV) laid the foundation for our current knowledge of how RNA Polymerase II is released from promoter-proximal pausing sites and transcription elongation is enhanced. The viral Tat activator recruits Positive Transcription Elongation Factor b (P-TEFb) and Super Elongation Complex (SEC) that jointly drive transcription elongation. While substantial progress in understanding the role of SEC in HIV gene transcription elongation has been obtained, defining of the mechanisms that govern SEC functions is still limited, and the role of SEC in controlling HIV transcription in the absence of Tat is less clear. Here we revisit the contribution of SEC in early steps of HIV gene transcription. In the absence of Tat, the AF4/FMR2 Family member 4 (AFF4) of SEC efficiently activates HIV transcription, while gene activation by its homolog AFF1 is substantially lower. Differential recruitment to the HIV promoter and association with Human Polymerase-Associated Factor complex (PAFc) play key role in this functional distinction between AFF4 and AFF1. Moreover, while depletion of cyclin T1 expression has subtle effects on HIV gene transcription in the absence of Tat, knockout (KO) of AFF1, AFF4, or both proteins slightly repress this early step of viral transcription. Upon Tat expression, HIV transcription reaches optimal levels despite KO of AFF1 or AFF4 expression. However, double AFF1/AFF4 KO completely diminishes Tat trans-activation. Significantly, our results show that P-TEFb phosphorylates AFF4 and modulates SEC assembly, AFF1/4 dimerization and recruitment to the viral promoter. We conclude that SEC promotes both early steps of HIV transcription in the absence of Tat, as well as elongation of transcription, when Tat is expressed. Significantly, SEC functions are modulated by P-TEFb.
Collapse
Affiliation(s)
- Alona Kuzmina
- a The Shraga Segal Department of Microbiology Immunology and Genetics Faculty of Health Sciences , Ben-Gurion University of the Negev , Israel
| | - Simona Krasnopolsky
- a The Shraga Segal Department of Microbiology Immunology and Genetics Faculty of Health Sciences , Ben-Gurion University of the Negev , Israel
| | - Ran Taube
- a The Shraga Segal Department of Microbiology Immunology and Genetics Faculty of Health Sciences , Ben-Gurion University of the Negev , Israel
| |
Collapse
|