1
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Francette AM, Arndt KM. Multiple direct and indirect roles of the Paf1 complex in transcription elongation, splicing, and histone modifications. Cell Rep 2024; 43:114730. [PMID: 39244754 DOI: 10.1016/j.celrep.2024.114730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 07/17/2024] [Accepted: 08/23/2024] [Indexed: 09/10/2024] Open
Abstract
The polymerase-associated factor 1 (Paf1) complex (Paf1C) is a conserved protein complex with critical functions during eukaryotic transcription. Previous studies showed that Paf1C is multi-functional, controlling specific aspects of transcription ranging from RNA polymerase II (RNAPII) processivity to histone modifications. However, it is unclear how specific Paf1C subunits directly impact transcription and coupled processes. We have compared conditional depletion to steady-state deletion for each Paf1C subunit to determine the direct and indirect contributions to gene expression in Saccharomyces cerevisiae. Using nascent transcript sequencing, RNAPII profiling, and modeling of transcription elongation dynamics, we have demonstrated direct effects of Paf1C subunits on RNAPII processivity and elongation rate and indirect effects on transcript splicing and repression of antisense transcripts. Further, our results suggest that the direct transcriptional effects of Paf1C cannot be readily assigned to any particular histone modification. This work comprehensively analyzes both the immediate and the extended roles of each Paf1C subunit in transcription elongation and transcript regulation.
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Affiliation(s)
- Alex M Francette
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Karen M Arndt
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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2
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Zhang S, Roeder RG. Resistance of estrogen receptor function to BET bromodomain inhibition is mediated by transcriptional coactivator cooperativity. Nat Struct Mol Biol 2024:10.1038/s41594-024-01384-6. [PMID: 39251822 DOI: 10.1038/s41594-024-01384-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Accepted: 08/01/2024] [Indexed: 09/11/2024]
Abstract
The bromodomain and extraterminal domain (BET) family of proteins are critical chromatin readers that bind to acetylated histones through their bromodomains to activate transcription. Here, we reveal that bromodomain inhibition fails to repress oncogenic targets of estrogen receptor because of an intrinsic transcriptional mechanism. While bromodomains are necessary for the transcription of many genes, bromodomain-containing protein 4 (BRD4) binds to estrogen receptor binding sites and activates transcription of critical oncogenes such as MYC, independently of its bromodomains. BRD4 associates with the Mediator complex and disruption of Mediator reduces BRD4's enhancer occupancy. Profiling changes of the post-initiation RNA polymerase II (Pol II)-associated factors revealed that BET proteins regulate interactions between Pol II and elongation factors SPT5, SPT6 and the polymerase-associated factor 1 complex, which associate with BET proteins independently of their bromodomains and mediate their transcription elongation effect. Our findings highlight the importance of bromodomain-independent functions and interactions of BET proteins in the development of future therapeutic strategies.
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Affiliation(s)
- Sicong Zhang
- Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, NY, USA.
| | - Robert G Roeder
- Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, NY, USA.
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3
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Yanagisawa T, Murayama Y, Ehara H, Goto M, Aoki M, Sekine SI. Structural basis of eukaryotic transcription termination by the Rat1 exonuclease complex. Nat Commun 2024; 15:7854. [PMID: 39245712 PMCID: PMC11381523 DOI: 10.1038/s41467-024-52157-0] [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: 03/12/2024] [Accepted: 08/28/2024] [Indexed: 09/10/2024] Open
Abstract
The 5´-3´ exoribonuclease Rat1/Xrn2 is responsible for the termination of eukaryotic mRNA transcription by RNAPII. Rat1 forms a complex with its partner proteins, Rai1 and Rtt103, and acts as a "torpedo" to bind transcribing RNAPII and dissociate DNA/RNA from it. Here we report the cryo-electron microscopy structures of the Rat1-Rai1-Rtt103 complex and three Rat1-Rai1-associated RNAPII complexes (type-1, type-1b, and type-2) from the yeast, Komagataella phaffii. The Rat1-Rai1-Rtt103 structure revealed that Rat1 and Rai1 form a heterotetramer with a single Rtt103 bound between two Rai1 molecules. In the type-1 complex, Rat1-Rai1 forms a heterodimer and binds to the RNA exit site of RNAPII to extract RNA into the Rat1 exonuclease active site. This interaction changes the RNA path in favor of termination (the "pre-termination" state). The type-1b and type-2 complexes have no bound DNA/RNA, likely representing the "post-termination" states. These structures illustrate the termination mechanism of eukaryotic mRNA transcription.
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Affiliation(s)
- Tatsuo Yanagisawa
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Yuko Murayama
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Haruhiko Ehara
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Mie Goto
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Mari Aoki
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - 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.
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4
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Tullius TW, Isaac RS, Dubocanin D, Ranchalis J, Churchman LS, Stergachis AB. RNA polymerases reshape chromatin architecture and couple transcription on individual fibers. Mol Cell 2024; 84:3209-3222.e5. [PMID: 39191261 DOI: 10.1016/j.molcel.2024.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 07/02/2024] [Accepted: 08/08/2024] [Indexed: 08/29/2024]
Abstract
RNA polymerases must initiate and pause within a complex chromatin environment, surrounded by nucleosomes and other transcriptional machinery. This environment creates a spatial arrangement along individual chromatin fibers ripe for both competition and coordination, yet these relationships remain largely unknown owing to the inherent limitations of traditional structural and sequencing methodologies. To address this, we employed long-read chromatin fiber sequencing (Fiber-seq) in Drosophila to visualize RNA polymerase (Pol) within its native chromatin context with single-molecule precision along up to 30 kb fibers. We demonstrate that Fiber-seq enables the identification of individual Pol II, nucleosome, and transcription factor footprints, revealing Pol II pausing-driven destabilization of downstream nucleosomes. Furthermore, we demonstrate pervasive direct distance-dependent transcriptional coupling between nearby Pol II genes, Pol III genes, and transcribed enhancers, modulated by local chromatin architecture. Overall, transcription initiation reshapes surrounding nucleosome architecture and couples nearby transcriptional machinery along individual chromatin fibers.
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Affiliation(s)
- Thomas W Tullius
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - R Stefan Isaac
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Danilo Dubocanin
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Jane Ranchalis
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA, USA
| | | | - Andrew B Stergachis
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA, USA; Department of Genome Sciences, University of Washington, Seattle, WA, USA; Brotman Baty Institute for Precision Medicine, Seattle, WA, USA.
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5
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Diao AJ, Su BG, Vos SM. Pause Patrol: Negative Elongation Factor's Role in Promoter-Proximal Pausing and Beyond. J Mol Biol 2024:168779. [PMID: 39241983 DOI: 10.1016/j.jmb.2024.168779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Revised: 08/27/2024] [Accepted: 08/30/2024] [Indexed: 09/09/2024]
Abstract
RNA polymerase (Pol) II is highly regulated to ensure appropriate gene expression. Early transcription elongation is associated with transient pausing of RNA Pol II in the promoter-proximal region. In multicellular organisms, this pausing is stabilized by the association of transcription elongation factors DRB-sensitivity inducing factor (DSIF) and Negative Elongation Factor (NELF). DSIF is a broadly conserved transcription elongation factor whereas NELF is mostly restricted to the metazoan lineage. Mounting evidence suggests that NELF association with RNA Pol II serves as checkpoint for either release into rapid and productive transcription elongation or premature termination at promoter-proximal pause sites. Here we summarize NELF's roles in promoter-proximal pausing, transcription termination, DNA repair, and signaling based on decades of cell biological, biochemical, and structural work and describe areas for future research.
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Affiliation(s)
- Annette J Diao
- Department of Biology, Massachusetts Institute of Technology, Building 68, 31 Ames St., Cambridge, MA 02139, United States
| | - Bonnie G Su
- Department of Biology, Massachusetts Institute of Technology, Building 68, 31 Ames St., Cambridge, MA 02139, United States
| | - Seychelle M Vos
- Department of Biology, Massachusetts Institute of Technology, Building 68, 31 Ames St., Cambridge, MA 02139, United States; Howard Hughes Medical Institute, United States.
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6
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Kuldell JC, Kaplan CD. RNA Polymerase II Activity Control of Gene Expression and Involvement in Disease. J Mol Biol 2024:168770. [PMID: 39214283 DOI: 10.1016/j.jmb.2024.168770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2024] [Revised: 08/26/2024] [Accepted: 08/26/2024] [Indexed: 09/04/2024]
Abstract
Gene expression is dependent on RNA Polymerase II (Pol II) activity in eukaryotes. In addition to determining the rate of RNA synthesis for all protein coding genes, Pol II serves as a platform for the recruitment of factors and regulation of co-transcriptional events, from RNA processing to chromatin modification and remodeling. The transcriptome can be shaped by changes in Pol II kinetics affecting RNA synthesis itself or because of alterations to co-transcriptional events that are responsive to or coupled with transcription. Genetic, biochemical, and structural approaches to Pol II in model organisms have revealed critical insights into how Pol II works and the types of factors that regulate it. The complexity of Pol II regulation generally increases with organismal complexity. In this review, we describe fundamental aspects of how Pol II activity can shape gene expression, discuss recent advances in how Pol II elongation is regulated on genes, and how altered Pol II function is linked to human disease and aging.
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Affiliation(s)
- James C Kuldell
- Department of Biological Sciences, 202A LSA, Fifth and Ruskin Avenues, University of Pittsburgh, Pittsburgh PA 15260, United States
| | - Craig D Kaplan
- Department of Biological Sciences, 202A LSA, Fifth and Ruskin Avenues, University of Pittsburgh, Pittsburgh PA 15260, United States.
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7
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Sun R, Fisher RP. The CDK9-SPT5 Axis in Control of Transcription Elongation by RNAPII. J Mol Biol 2024:168746. [PMID: 39147127 DOI: 10.1016/j.jmb.2024.168746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Revised: 08/09/2024] [Accepted: 08/09/2024] [Indexed: 08/17/2024]
Abstract
The RNA polymerase II (RNAPII) transcription cycle is regulated at every stage by a network of cyclin-dependent protein kinases (CDKs) and protein phosphatases. Progression of RNAPII from initiation to termination is marked by changing patterns of phosphorylation on the highly repetitive carboxy-terminal domain (CTD) of RPB1, its largest subunit, suggesting the existence of a CTD code. In parallel, the conserved transcription elongation factor SPT5, large subunit of the DRB sensitivity-inducing factor (DSIF), undergoes spatiotemporally regulated changes in phosphorylation state that may be directly linked to the transitions between transcription-cycle phases. Here we review insights gained from recent structural, biochemical, and genetic analyses of human SPT5, which suggest that two of its phosphorylated regions perform distinct functions at different points in transcription. Phosphorylation within a flexible, RNA-binding linker promotes release from the promoter-proximal pause-frequently a rate-limiting step in gene expression-whereas modifications in a repetitive carboxy-terminal region are thought to favor processive elongation, and are removed just prior to termination. Phosphorylations in both motifs depend on CDK9, catalytic subunit of positive transcription elongation factor b (P-TEFb); their different timing of accumulation on chromatin and function during the transcription cycle might reflect their removal by different phosphatases, different kinetics of phosphorylation by CDK9, or both. Perturbations of SPT5 regulation have profound impacts on viability and development in model organisms through largely unknown mechanisms, while enzymes that modify SPT5 have emerged as potential therapeutic targets in cancer; elucidating a putative SPT5 code is therefore a high priority.
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Affiliation(s)
- Rui Sun
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029-6574, USA
| | - Robert P Fisher
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029-6574, USA.
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8
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Chen M. Puff, the polytene chromosome: Visualizing transcription elongation control. Mol Cell 2024; 84:2799-2801. [PMID: 39121840 DOI: 10.1016/j.molcel.2024.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2024] [Revised: 07/12/2024] [Accepted: 07/12/2024] [Indexed: 08/12/2024]
Abstract
In this issue, Versluis et al.1 use a highly sensitive live-cell imaging system to examine transcription dynamics and functions of various key transcription elongation regulators at the Hsp70 loci.
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Affiliation(s)
- Mo Chen
- State Key Laboratory of Molecular Oncology, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China; SXMU-Tsinghua Collaborative Innovation Center for Frontier Medicine, Shanxi Medical University, Taiyuan, China.
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9
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Versluis P, Graham TGW, Eng V, Ebenezer J, Darzacq X, Zipfel WR, Lis JT. Live-cell imaging of RNA Pol II and elongation factors distinguishes competing mechanisms of transcription regulation. Mol Cell 2024; 84:2856-2869.e9. [PMID: 39121843 DOI: 10.1016/j.molcel.2024.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 04/22/2024] [Accepted: 07/11/2024] [Indexed: 08/12/2024]
Abstract
RNA polymerase II (RNA Pol II)-mediated transcription is a critical, highly regulated process aided by protein complexes at distinct steps. Here, to investigate RNA Pol II and transcription-factor-binding and dissociation dynamics, we generated endogenous photoactivatable-GFP (PA-GFP) and HaloTag knockins using CRISPR-Cas9, allowing us to track a population of molecules at the induced Hsp70 loci in Drosophila melanogaster polytene chromosomes. We found that early in the heat-shock response, little RNA Pol II and DRB sensitivity-inducing factor (DSIF) are reused for iterative rounds of transcription. Surprisingly, although PAF1 and Spt6 are found throughout the gene body by chromatin immunoprecipitation (ChIP) assays, they show markedly different binding behaviors. Additionally, we found that PAF1 and Spt6 are only recruited after positive transcription elongation factor (P-TEFb)-mediated phosphorylation and RNA Pol II promoter-proximal pause escape. Finally, we observed that PAF1 may be expendable for transcription of highly expressed genes where nucleosome density is low. Thus, our live-cell imaging data provide key constraints to mechanistic models of transcription regulation.
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Affiliation(s)
- Philip Versluis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Thomas G W Graham
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Vincent Eng
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Jonathan Ebenezer
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA; Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Xavier Darzacq
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Warren R Zipfel
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
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10
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Lopez Martinez D, Svejstrup JQ. Mechanisms of RNA Polymerase II Termination at the 3'-End of Genes. J Mol Biol 2024:168735. [PMID: 39098594 DOI: 10.1016/j.jmb.2024.168735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 07/23/2024] [Accepted: 07/30/2024] [Indexed: 08/06/2024]
Abstract
RNA polymerase II (RNAPII) is responsible for the synthesis of a diverse set of RNA molecules, including protein-coding messenger RNAs (mRNAs) and many short non-coding RNAs (ncRNAs). For this purpose, RNAPII relies on a multitude of factors that regulate the transcription cycle, from initiation and promoter-proximal pausing, through elongation and finally termination. RNAPII transcription termination at the end of genes ensures the release of RNAPII from the DNA template and its efficient recycling for further rounds of transcription. Termination of RNAPII is tightly coupled to 3'-end mRNA processing, which constitutes an important trigger for the subsequent transcription termination event. In this review, we discuss the current understanding of RNAPII termination mechanisms, focusing on 'canonical' termination at the 3'-end of genes. We also integrate the allosteric and 'torpedo' models into a unified model of termination, and describe the different termination factors that have been identified to date, paying special attention to the human factors and their mechanism of action at the molecular level. Indeed, in recent years the development of novel approaches in structural biology, biochemistry and cell biology have together led to a more detailed comprehension of the different mechanisms of RNAPII termination, and a better understanding of their importance in regulating gene expression, especially under cellular stress and pathological situations.
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Affiliation(s)
- David Lopez Martinez
- Centre for Gene Expression, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark.
| | - Jesper Q Svejstrup
- Centre for Gene Expression, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark.
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11
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Walker RL, Hornicek FJ, Duan Z. Transcriptional regulation and therapeutic potential of cyclin-dependent kinase 9 (CDK9) in sarcoma. Biochem Pharmacol 2024; 226:116342. [PMID: 38848777 DOI: 10.1016/j.bcp.2024.116342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/17/2024] [Accepted: 06/04/2024] [Indexed: 06/09/2024]
Abstract
Sarcomas include various subtypes comprising two significant groups - soft tissue and bone sarcomas. Although the survival rate for some sarcoma subtypes has improved over time, the current methods of treatment remain efficaciously limited, as recurrent, and metastatic diseases remain a major obstacle. There is a need for better options and therapeutic strategies in treating sarcoma. Cyclin dependent kinase 9 (CDK9) is a transcriptional kinase and has emerged as a promising target for treating various cancers. The aberrant expression and activation of CDK9 have been observed in several sarcoma subtypes, including rhabdomyosarcoma, synovial sarcoma, osteosarcoma, Ewing sarcoma, and chordoma. Enhanced CDK9 expression has also been correlated with poorer prognosis in sarcoma patients. As a master regulator of transcription, CDK9 promotes transcription elongation by phosphorylation and releasing RNA polymerase II (RNAPII) from its promoter proximal pause. Release of RNAPII from this pause induces transcription of critical genes in the tumor cell. Overexpression and activation of CDK9 have been observed to lead to the expression of oncogenes, including MYC and MCL-1, that aid sarcoma development and progression. Inhibition of CDK9 in sarcoma has been proven to reduce these oncogenes' expression and decrease proliferation and growth in different sarcoma cells. Currently, there are several CDK9 inhibitors in preclinical and clinical investigations. This review aims to highlight the recent discovery and results on the transcriptional role and therapeutic potential of CDK9 in sarcoma.
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Affiliation(s)
- Robert L Walker
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA
| | - Francis J Hornicek
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA
| | - Zhenfeng Duan
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA.
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12
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Fisher MJ, Luse DS. Defining a chromatin architecture that supports transcription at RNA polymerase II promoters. J Biol Chem 2024; 300:107515. [PMID: 38945447 PMCID: PMC11298586 DOI: 10.1016/j.jbc.2024.107515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/19/2024] [Accepted: 06/25/2024] [Indexed: 07/02/2024] Open
Abstract
Mammalian RNA polymerase II preinitiation complexes assemble adjacent to a nucleosome whose proximal edge (NPE) is typically 40 to 50 bp downstream of the transcription start site. At active promoters, that +1 nucleosome is universally modified by trimethylation on lysine 4 of histone H3 (H3K4me3). The Pol II preinitiation complex only extends 35 bp beyond the transcription start site, but nucleosomal templates with an NPE at +51 are nearly inactive in vitro with promoters that lack a TATA element and thus depend on TFIID for promoter recognition. Significantly, this inhibition is relieved when the +1 nucleosome contains H3K4me3, which can interact with TFIID subunits. Here, we show that H3K4me3 templates with both TATA and TATA-less promoters are active with +35 NPEs when transcription is driven by TFIID. Templates with +20 NPE are also active but at reduced levels compared to +35 and +51 NPEs, consistent with a general inhibition of promoter function when the proximal nucleosome encroaches on the preinitiation complex. Remarkably, dinucleosome templates support transcription when H3K4me3 is only present in the distal nucleosome, suggesting that TFIID-H3K4me3 interaction does not require modification of the +1 nucleosome. Transcription reactions performed with an alternative protocol retaining most nuclear factors results primarily in early termination, with a minority of complexes successfully traversing the first nucleosome. In such reactions, the +1 nucleosome does not substantially affect the level of termination even with an NPE of +20, indicating that a nucleosome barrier is not a major driver of early termination by Pol II.
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Affiliation(s)
- Michael J Fisher
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Donal S Luse
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.
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13
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Hou Y, Zhang C, Liu L, Yu Y, Shi L, Qin Y. WDR61 ablation triggers R-loop accumulation and suppresses breast cancer progression. FEBS J 2024; 291:3417-3431. [PMID: 38708718 DOI: 10.1111/febs.17145] [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: 09/29/2023] [Revised: 02/09/2024] [Accepted: 04/12/2024] [Indexed: 05/07/2024]
Abstract
Although, superkiller complex protein 8 (SKI8), previously known as WDR61 has been identified and mapped in breast tumor, little is currently known about its function. This study aims to elucidate the role of WDR61 in breast tumor development and its potential as a therapeutic target. Here, we show that tamoxifen-induced knockout of Wdr61 reduces the risk of breast tumors, resulting in smaller tumor size and weight, and improved overall survival. Furthermore, we show that knockdown of WDR61 compromises the proliferation of breast tumor cells with reduced colony-forming capacity. Further investigations demonstrate that the protective effect of WDR61 loss on breast tumor development is due to genomic instability. Mechanistic studies reveal that WDR61 interacts with the R-loop, and loss of WDR61 leads to R-loops accumulation in breast tumor cells, causing DNA damage and subsequent inhibition of cell proliferation. In summary, this study highlights the critical dependence of breast tumors on WDR61, which suppresses R-loop and counteracts endogenous DNA damage in tumor cells.
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Affiliation(s)
- Yayan Hou
- State Key Laboratory of Experimental Hematology, Haihe Laboratory of Cell Ecosystem, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, China
| | - Chunyong Zhang
- State Key Laboratory of Experimental Hematology, Haihe Laboratory of Cell Ecosystem, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, China
| | - Ling Liu
- State Key Laboratory of Experimental Hematology, Haihe Laboratory of Cell Ecosystem, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, China
| | - Ying Yu
- State Key Laboratory of Experimental Hematology, Haihe Laboratory of Cell Ecosystem, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, China
| | - Lei Shi
- State Key Laboratory of Experimental Hematology, Haihe Laboratory of Cell Ecosystem, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, China
| | - Yan Qin
- State Key Laboratory of Experimental Hematology, Haihe Laboratory of Cell Ecosystem, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, China
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14
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Zhang S, Roeder RG. Resistance of estrogen receptor function to BET bromodomain inhibition is mediated by transcriptional coactivator cooperativity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.25.605008. [PMID: 39211208 PMCID: PMC11361192 DOI: 10.1101/2024.07.25.605008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
The Bromodomain and Extra-Terminal Domain (BET) family of proteins are critical chromatin readers that bind to acetylated histones through their bromodomains to activate transcription. Here, we reveal that bromodomain inhibition fails to repress oncogenic targets of estrogen receptor due to an intrinsic transcriptional mechanism. While bromodomains are necessary for the transcription of many genes, BRD4 binds to estrogen receptor binding sites and activates transcription of critical oncogenes independently of its bromodomains. BRD4 associates with the Mediator complex and disruption of Mediator complex reduces BRD4's enhancer occupancy. Profiling changes in the post-initiation RNA polymerase II (Pol II)-associated factors revealed that BET proteins regulate interactions between Pol II and elongation factors SPT5, SPT6, and PAF1 complex, which associate with BET proteins independently of their bromodomains and mediate their transcription elongation effect. Our findings highlight the importance of bromodomain-independent functions and interactions of BET proteins in the development of future therapeutic strategies.
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15
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Sun R, Fisher RP. Coordinate control of the RNA polymerase II transcription cycle by CDK9-dependent, tripartite phosphorylation of SPT5. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.25.605161. [PMID: 39211083 PMCID: PMC11360971 DOI: 10.1101/2024.07.25.605161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
The RNA polymerase II (RNAPII) transcription cycle is regulated throughout its duration by reversible protein phosphorylation. The elongation factor SPT5 contains two regions targeted by cyclin-dependent kinase 9 (CDK9) and previously implicated in promoter-proximal pausing and termination: the linker between KOWx-4 and KOW5 domains and carboxy-terminal repeat (CTR) 1, respectively. Here we show that phosphorylations in the KOWx-4/5 linker, CTR1 and a third region, CTR2, coordinately control pause release, elongation speed and RNA processing. Pausing was increased by mutations preventing CTR1 or CTR2 phosphorylation, but attenuated when both CTRs were mutated. Whereas mutating CTR1 alone slowed elongation and repressed nascent transcription, simultaneous mutation of CTR2 partially reversed both effects. Nevertheless, mutating both CTRs led to aberrant splicing, dysregulated termination and diminished steady-state mRNA levels, and impaired cell proliferation more severely than did either single-CTR mutation. Therefore, tripartite SPT5 phosphorylation times pause release and regulates RNAPII elongation rates positively and negatively to ensure productive transcription and cell viability.
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16
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Qin Y, Meng FL. Taming AID mutator activity in somatic hypermutation. Trends Biochem Sci 2024; 49:622-632. [PMID: 38614818 DOI: 10.1016/j.tibs.2024.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 03/05/2024] [Accepted: 03/19/2024] [Indexed: 04/15/2024]
Abstract
Activation-induced cytidine deaminase (AID) initiates somatic hypermutation (SHM) by introducing base substitutions into antibody genes, a process enabling antibody affinity maturation in immune response. How a mutator is tamed to precisely and safely generate programmed DNA lesions in a physiological process remains unsettled, as its dysregulation drives lymphomagenesis. Recent research has revealed several hidden features of AID-initiated mutagenesis: preferential activity on flexible DNA substrates, restrained activity within chromatin loop domains, unique DNA repair factors to differentially decode AID-caused lesions, and diverse consequences of aberrant deamination. Here, we depict the multifaceted regulation of AID activity with a focus on emerging concepts/factors and discuss their implications for the design of base editors (BEs) that install somatic mutations to correct deleterious genomic variants.
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Affiliation(s)
- Yining Qin
- Key Laboratory of RNA Science and Engineering, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences; Shanghai 200031, China
| | - Fei-Long Meng
- Key Laboratory of RNA Science and Engineering, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences; Shanghai 200031, China.
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17
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Velychko T, Mohammad E, Ferrer-Vicens I, Parfentev I, Werner M, Studniarek C, Schwalb B, Urlaub H, Murphy S, Cramer P, Lidschreiber M. CDK7 kinase activity promotes RNA polymerase II promoter escape by facilitating initiation factor release. Mol Cell 2024; 84:2287-2303.e10. [PMID: 38821049 DOI: 10.1016/j.molcel.2024.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 02/01/2024] [Accepted: 05/08/2024] [Indexed: 06/02/2024]
Abstract
Cyclin-dependent kinase 7 (CDK7), part of the general transcription factor TFIIH, promotes gene transcription by phosphorylating the C-terminal domain of RNA polymerase II (RNA Pol II). Here, we combine rapid CDK7 kinase inhibition with multi-omics analysis to unravel the direct functions of CDK7 in human cells. CDK7 inhibition causes RNA Pol II retention at promoters, leading to decreased RNA Pol II initiation and immediate global downregulation of transcript synthesis. Elongation, termination, and recruitment of co-transcriptional factors are not directly affected. Although RNA Pol II, initiation factors, and Mediator accumulate at promoters, RNA Pol II complexes can also proceed into gene bodies without promoter-proximal pausing while retaining initiation factors and Mediator. Further downstream, RNA Pol II phosphorylation increases and initiation factors and Mediator are released, allowing recruitment of elongation factors and an increase in RNA Pol II elongation velocity. Collectively, CDK7 kinase activity promotes the release of initiation factors and Mediator from RNA Pol II, facilitating RNA Pol II escape from the promoter.
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Affiliation(s)
- Taras Velychko
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Eusra Mohammad
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Ivan Ferrer-Vicens
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Iwan Parfentev
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Marcel Werner
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Cecilia Studniarek
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Björn Schwalb
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany; Institute of Clinical Chemistry, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Shona Murphy
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany.
| | - Michael Lidschreiber
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany.
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18
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Liu Y, Flamier A, Bell GW, Diao AJ, Whitfield TW, Wang HC, Wu Y, Schulte F, Friesen M, Guo R, Mitalipova M, Liu XS, Vos SM, Young RA, Jaenisch R. MECP2 directly interacts with RNA polymerase II to modulate transcription in human neurons. Neuron 2024; 112:1943-1958.e10. [PMID: 38697112 DOI: 10.1016/j.neuron.2024.04.007] [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: 11/17/2023] [Revised: 03/08/2024] [Accepted: 04/05/2024] [Indexed: 05/04/2024]
Abstract
Mutations in the methyl-DNA-binding protein MECP2 cause the neurodevelopmental disorder Rett syndrome (RTT). How MECP2 contributes to transcriptional regulation in normal and disease states is unresolved; it has been reported to be an activator and a repressor. We describe here the first integrated CUT&Tag, transcriptome, and proteome analyses using human neurons with wild-type (WT) and mutant MECP2 molecules. MECP2 occupies CpG-rich promoter-proximal regions in over four thousand genes in human neurons, including a plethora of autism risk genes, together with RNA polymerase II (RNA Pol II). MECP2 directly interacts with RNA Pol II, and genes occupied by both proteins showed reduced expression in neurons with MECP2 patient mutations. We conclude that MECP2 acts as a positive cofactor for RNA Pol II gene expression at many neuronal genes that harbor CpG islands in promoter-proximal regions and that RTT is due, in part, to the loss of gene activity of these genes in neurons.
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Affiliation(s)
- Yi Liu
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Anthony Flamier
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - George W Bell
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Annette Jun Diao
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Troy W Whitfield
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Hao-Che Wang
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Yizhe Wu
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Fabian Schulte
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Max Friesen
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Ruisi Guo
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Maisam Mitalipova
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - X Shawn Liu
- Department of Physiology and Cellular Biophysics, Columbia University Medical Center, New York, NY 10032, USA
| | - Seychelle M Vos
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Richard A Young
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Rudolf Jaenisch
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
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19
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Birkenheuer CH, Baines JD. Aberrant RNA polymerase initiation and processivity on the genome of a herpes simplex virus 1 mutant lacking ICP27. J Virol 2024; 98:e0071224. [PMID: 38780246 PMCID: PMC11237563 DOI: 10.1128/jvi.00712-24] [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: 04/19/2024] [Accepted: 04/23/2024] [Indexed: 05/25/2024] Open
Abstract
Within the first 15 minutes of infection, herpes simplex virus 1 immediate early proteins repurpose cellular RNA polymerase (Pol II) for viral transcription. An important role of the viral-infected cell protein 27 (ICP27) is to facilitate viral pre-mRNA processing and export viral mRNA to the cytoplasm. Here, we use precision nuclear run-on followed by deep sequencing (PRO-seq) to characterize transcription of a viral ICP27 null mutant. At 1.5 and 3 hours post infection (hpi), we observed increased total levels of Pol II on the mutant viral genome and accumulation of Pol II downstream of poly A sites indicating increased levels of initiation and processivity. By 6 hpi, Pol II accumulation on specific mutant viral genes was higher than that on wild-type virus either at or upstream of poly A signals, depending on the gene. The PRO-seq profile of the ICP27 mutant on late genes at 6 hpi was similar but not identical to that caused by treatment with flavopiridol, a known inhibitor of RNA processivity. This pattern was different from PRO-seq profiles of other α gene mutants and upon inhibition of viral DNA replication with PAA. Together, these results indicate that ICP27 contributes to the repression of aberrant viral transcription at 1.5 and 3 hpi by inhibiting initiation and decreasing RNA processivity. However, ICP27 is needed to enhance processivity on most late genes by 6 hpi in a mechanism distinguishable from its role in viral DNA replication.IMPORTANCEWe developed and validated the use of a processivity index for precision nuclear run-on followed by deep sequencing data. The processivity index calculations confirm infected cell protein 27 (ICP27) induces downstream of transcription termination on certain host genes. The processivity indices and whole gene probe data implicate ICP27 in transient immediate early gene-mediated repression, a process that also requires ICP4, ICP22, and ICP0. The data indicate that ICP27 directly or indirectly regulates RNA polymerase (Pol II) initiation and processivity on specific genes at specific times post infection. These observations support specific and varied roles for ICP27 in regulating Pol II activity on viral genes in addition to its known roles in post transcriptional mRNA processing and export.
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Affiliation(s)
- Claire H. Birkenheuer
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Joel D. Baines
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
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20
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Žumer K, Ochmann M, Aljahani A, Zheenbekova A, Devadas A, Maier KC, Rus P, Neef U, Oudelaar AM, Cramer P. FACT maintains chromatin architecture and thereby stimulates RNA polymerase II pausing during transcription in vivo. Mol Cell 2024; 84:2053-2069.e9. [PMID: 38810649 DOI: 10.1016/j.molcel.2024.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 03/06/2024] [Accepted: 05/02/2024] [Indexed: 05/31/2024]
Abstract
Facilitates chromatin transcription (FACT) is a histone chaperone that supports transcription through chromatin in vitro, but its functional roles in vivo remain unclear. Here, we analyze the in vivo functions of FACT with the use of multi-omics analysis after rapid FACT depletion from human cells. We show that FACT depletion destabilizes chromatin and leads to transcriptional defects, including defective promoter-proximal pausing and elongation, and increased premature termination of RNA polymerase II. Unexpectedly, our analysis revealed that promoter-proximal pausing depends not only on the negative elongation factor (NELF) but also on the +1 nucleosome, which is maintained by FACT.
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Affiliation(s)
- Kristina Žumer
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany.
| | - Moritz Ochmann
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Abrar Aljahani
- Max Planck Institute for Multidisciplinary Sciences, Genome Organization and Regulation, Am Fassberg 11, 37077 Göttingen, Germany
| | - Aiturgan Zheenbekova
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Arjun Devadas
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Kerstin Caroline Maier
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Petra Rus
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Ute Neef
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - A Marieke Oudelaar
- Max Planck Institute for Multidisciplinary Sciences, Genome Organization and Regulation, Am Fassberg 11, 37077 Göttingen, Germany.
| | - Patrick Cramer
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany.
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21
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Nogales E. Building up complexity in structural biology studies. Nat Struct Mol Biol 2024; 31:847-848. [PMID: 38816465 DOI: 10.1038/s41594-024-01324-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Affiliation(s)
- Eva Nogales
- Molecular and Cell Biology Department, University of California, Berkeley, Berkeley, CA, USA.
- Howard Hughes Medical Institute, Berkeley, CA, USA.
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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22
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Milne TA. Chromatin and aberrant enhancer activity in KMT2A rearranged acute lymphoblastic leukemia. Curr Opin Genet Dev 2024; 86:102191. [PMID: 38579381 DOI: 10.1016/j.gde.2024.102191] [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: 12/18/2023] [Revised: 03/11/2024] [Accepted: 03/19/2024] [Indexed: 04/07/2024]
Abstract
To make a multicellular organism, genes need to be transcribed at the right developmental stages and in the right tissues. DNA sequences termed 'enhancers' are crucial to achieve this. Despite concerted efforts, the exact mechanisms of enhancer activity remain elusive. Mixed lineage leukemia (MLL or KMT2A) rearrangements (MLLr), commonly observed in cases of acute lymphoblastic leukemia (ALL) and acute myeloid leukemia, produce novel in-frame fusion proteins. Recent work has shown that the MLL-AF4 fusion protein drives aberrant enhancer activity at key oncogenes in ALL, dependent on the continued presence of MLL-AF4 complex components. As well as providing some general insights into enhancer function, these observations may also provide an explanation for transcriptional heterogeneity observed in MLLr patients.
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Affiliation(s)
- Thomas A Milne
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK.
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23
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Gillis A, Berry S. Global control of RNA polymerase II. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2024; 1867:195024. [PMID: 38552781 DOI: 10.1016/j.bbagrm.2024.195024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 04/11/2024]
Abstract
RNA polymerase II (Pol II) is the multi-protein complex responsible for transcribing all protein-coding messenger RNA (mRNA). Most research on gene regulation is focused on the mechanisms controlling which genes are transcribed when, or on the mechanics of transcription. How global Pol II activity is determined receives comparatively less attention. Here, we follow the life of a Pol II molecule from 'assembly of the complex' to nuclear import, enzymatic activity, and degradation. We focus on how Pol II spends its time in the nucleus, and on the two-way relationship between Pol II abundance and activity in the context of homeostasis and global transcriptional changes.
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Affiliation(s)
- Alexander Gillis
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia; UNSW RNA Institute, University of New South Wales, Sydney, Australia; Department of Molecular Medicine, School of Biomedical Sciences, University of New South Wales, Sydney, Australia
| | - Scott Berry
- EMBL Australia Node in Single Molecule Science, University of New South Wales, Sydney, Australia; UNSW RNA Institute, University of New South Wales, Sydney, Australia; Department of Molecular Medicine, School of Biomedical Sciences, University of New South Wales, Sydney, Australia
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24
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Li Y, Wang Q, Xu Y, Li Z. Structures of co-transcriptional RNA capping enzymes on paused transcription complex. Nat Commun 2024; 15:4622. [PMID: 38816438 PMCID: PMC11139899 DOI: 10.1038/s41467-024-48963-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 05/17/2024] [Indexed: 06/01/2024] Open
Abstract
The 5'-end capping of nascent pre-mRNA represents the initial step in RNA processing, with evidence demonstrating that guanosine addition and 2'-O-ribose methylation occur in tandem with early steps of transcription by RNA polymerase II, especially at the pausing stage. Here, we determine the cryo-EM structures of the paused elongation complex in complex with RNGTT, as well as the paused elongation complex in complex with RNGTT and CMTR1. Our findings show the simultaneous presence of RNGTT and the NELF complex bound to RNA polymerase II. The NELF complex exhibits two conformations, one of which shows a notable rearrangement of NELF-A/D compared to that of the paused elongation complex. Moreover, CMTR1 aligns adjacent to RNGTT on the RNA polymerase II stalk. Our structures indicate that RNGTT and CMTR1 directly bind the paused elongation complex, illuminating the mechanism by which 5'-end capping of pre-mRNA during transcriptional pausing.
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Affiliation(s)
- Yan Li
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai, 200032, China
| | - Qianmin Wang
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai, 200032, China
| | - Yanhui Xu
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai, 200032, China
- The International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, China, Department of Systems Biology for Medicine, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, 200032, China
| | - Ze Li
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai, 200032, China.
- The International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, China, Department of Systems Biology for Medicine, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, 200032, China.
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25
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Liu Y, Shu J, Zhang Z, Ding N, Liu J, Liu J, Cui Y, Wang C, Chen C. A conserved Pol II elongator SPT6L mediates Pol V transcription to regulate RNA-directed DNA methylation in Arabidopsis. Nat Commun 2024; 15:4460. [PMID: 38796517 PMCID: PMC11127964 DOI: 10.1038/s41467-024-48940-8] [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: 07/04/2023] [Accepted: 05/14/2024] [Indexed: 05/28/2024] Open
Abstract
In plants, the plant-specific RNA polymerase V (Pol V) transcripts non-coding RNAs and provides a docking platform for the association of accessory proteins in the RNA-directed DNA methylation (RdDM) pathway. Various components have been uncovered that are involved in the process of DNA methylation, but it is still not clear how the transcription of Pol V is regulated. Here, we report that the conserved RNA polymerase II (Pol II) elongator, SPT6L, binds to thousands of intergenic regions in a Pol II-independent manner. The intergenic enrichment of SPT6L, interestingly, co-occupies with the largest subunit of Pol V (NRPE1) and mutation of SPT6L leads to the reduction of DNA methylation but not Pol V enrichment. Furthermore, the association of SPT6L at Pol V loci is dependent on the Pol V associated factor, SPT5L, rather than the presence of Pol V, and the interaction between SPT6L and NRPE1 is compromised in spt5l. Finally, Pol V RIP-seq reveals that SPT6L is required to maintain the amount and length of Pol V transcripts. Our findings thus uncover the critical role of a Pol II conserved elongator in Pol V mediated DNA methylation and transcription, and shed light on the mutual regulation between Pol V and II in plants.
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Affiliation(s)
- Yujuan Liu
- State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China
- University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Jie Shu
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China
- Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong, 510640, China
| | - Zhi Zhang
- State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China
- University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Ning Ding
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Jinyuan Liu
- State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China
- University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Jun Liu
- Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong, 510640, China
| | - Yuhai Cui
- Agriculture and Agri-Food Canada, London Research and Development Centre, London, ON, N5V 4T3, Canada
- Department of Biology, Western University, London, ON, N6A 5B7, Canada
| | - Changhu Wang
- State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China.
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China.
- University of the Chinese Academy of Sciences, Beijing, 100049, China.
| | - Chen Chen
- State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China.
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, 510650, China.
- University of the Chinese Academy of Sciences, Beijing, 100049, China.
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26
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Zhan Y, Grabbe F, Oberbeckmann E, Dienemann C, Cramer P. Three-step mechanism of promoter escape by RNA polymerase II. Mol Cell 2024; 84:1699-1710.e6. [PMID: 38604172 DOI: 10.1016/j.molcel.2024.03.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 01/04/2024] [Accepted: 03/16/2024] [Indexed: 04/13/2024]
Abstract
The transition from transcription initiation to elongation is highly regulated in human cells but remains incompletely understood at the structural level. In particular, it is unclear how interactions between RNA polymerase II (RNA Pol II) and initiation factors are broken to enable promoter escape. Here, we reconstitute RNA Pol II promoter escape in vitro and determine high-resolution structures of initially transcribing complexes containing 8-, 10-, and 12-nt ordered RNAs and two elongation complexes containing 14-nt RNAs. We suggest that promoter escape occurs in three major steps. First, the growing RNA displaces the B-reader element of the initiation factor TFIIB without evicting TFIIB. Second, the rewinding of the transcription bubble coincides with the eviction of TFIIA, TFIIB, and TBP. Third, the binding of DSIF and NELF facilitates TFIIE and TFIIH dissociation, establishing the paused elongation complex. This three-step model for promoter escape fills a gap in our understanding of the initiation-elongation transition of RNA Pol II transcription.
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Affiliation(s)
- Yumeng Zhan
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Frauke Grabbe
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Elisa Oberbeckmann
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Christian Dienemann
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany.
| | - Patrick Cramer
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany.
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27
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Fianu I, Ochmann M, Walshe JL, Dybkov O, Cruz JN, Urlaub H, Cramer P. Structural basis of Integrator-dependent RNA polymerase II termination. Nature 2024; 629:219-227. [PMID: 38570683 PMCID: PMC11062913 DOI: 10.1038/s41586-024-07269-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 03/05/2024] [Indexed: 04/05/2024]
Abstract
The Integrator complex can terminate RNA polymerase II (Pol II) in the promoter-proximal region of genes. Previous work has shed light on how Integrator binds to the paused elongation complex consisting of Pol II, the DRB sensitivity-inducing factor (DSIF) and the negative elongation factor (NELF) and how it cleaves the nascent RNA transcript1, but has not explained how Integrator removes Pol II from the DNA template. Here we present three cryo-electron microscopy structures of the complete Integrator-PP2A complex in different functional states. The structure of the pre-termination complex reveals a previously unresolved, scorpion-tail-shaped INTS10-INTS13-INTS14-INTS15 module that may use its 'sting' to open the DSIF DNA clamp and facilitate termination. The structure of the post-termination complex shows that the previously unresolved subunit INTS3 and associated sensor of single-stranded DNA complex (SOSS) factors prevent Pol II rebinding to Integrator after termination. The structure of the free Integrator-PP2A complex in an inactive closed conformation2 reveals that INTS6 blocks the PP2A phosphatase active site. These results lead to a model for how Integrator terminates Pol II transcription in three steps that involve major rearrangements.
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Affiliation(s)
- Isaac Fianu
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
| | - Moritz Ochmann
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - James L Walshe
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Olexandr Dybkov
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Joseph Neos Cruz
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Institute of Clinical Chemistry, Bioanalytics Group, University Medical Center Göttingen, Göttingen, Germany
- Cluster of Excellence 'Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells' (MBExC), University of Göttingen, Göttingen, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
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28
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Obermeyer S, Kapoor H, Markusch H, Grasser KD. Transcript elongation by RNA polymerase II in plants: factors, regulation and impact on gene expression. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:645-656. [PMID: 36703573 DOI: 10.1111/tpj.16115] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/12/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Transcriptional elongation by RNA polymerase II (RNAPII) through chromatin is a dynamic and highly regulated step of eukaryotic gene expression. A combination of transcript elongation factors (TEFs) including modulators of RNAPII activity and histone chaperones facilitate efficient transcription on nucleosomal templates. Biochemical and genetic analyses, primarily performed in Arabidopsis, provided insight into the contribution of TEFs to establish gene expression patterns during plant growth and development. In addition to summarising the role of TEFs in plant gene expression, we emphasise in our review recent advances in the field. Thus, mechanisms are presented how aberrant intragenic transcript initiation is suppressed by repressing transcriptional start sites within coding sequences. We also discuss how transcriptional interference of ongoing transcription with neighbouring genes is prevented. Moreover, it appears that plants make no use of promoter-proximal RNAPII pausing in the way mammals do, but there are nucleosome-defined mechanism(s) that determine the efficiency of mRNA synthesis by RNAPII. Accordingly, a still growing number of processes related to plant growth, development and responses to changing environmental conditions prove to be regulated at the level of transcriptional elongation.
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Affiliation(s)
- Simon Obermeyer
- Cell Biology and Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053, Regensburg, Germany
| | - Henna Kapoor
- Cell Biology and Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053, Regensburg, Germany
| | - Hanna Markusch
- Cell Biology and Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053, Regensburg, Germany
| | - Klaus D Grasser
- Cell Biology and Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053, Regensburg, Germany
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29
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Blanco-Touriñán N, Pérez-Alemany J, Bourbousse C, Latrasse D, Ait-Mohamed O, Benhamed M, Barneche F, Blázquez MA, Gallego-Bartolomé J, Alabadí D. The plant POLYMERASE-ASSOCIATED FACTOR1 complex links transcription and H2B monoubiquitination genome wide. PLANT PHYSIOLOGY 2024; 195:640-651. [PMID: 38285074 PMCID: PMC11060679 DOI: 10.1093/plphys/kiae041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/20/2023] [Accepted: 12/25/2023] [Indexed: 01/30/2024]
Abstract
The evolutionarily conserved POLYMERASE-ASSOCIATED FACTOR1 complex (Paf1C) participates in transcription, and research in animals and fungi suggests that it facilitates RNA POLYMERASE II (RNAPII) progression through chromatin. We examined the genomic distribution of the EARLY FLOWERING7 (ELF7) and VERNALIZATION INDEPENDENCE3 subunits of Paf1C in Arabidopsis (Arabidopsis thaliana). The occupancy of both subunits was confined to thousands of gene bodies and positively associated with RNAPII occupancy and the level of gene expression, supporting a role as a transcription elongation factor. We found that monoubiquitinated histone H2B, which marks most transcribed genes, was strongly reduced genome wide in elf7 seedlings. Genome-wide profiling of RNAPII revealed that in elf7 mutants, RNAPII occupancy was reduced throughout the gene body and at the transcription end site of Paf1C-targeted genes, suggesting a direct role for the complex in transcription elongation. Overall, our observations suggest a direct functional link between Paf1C activity, monoubiquitination of histone H2B, and the transition of RNAPII to productive elongation. However, for several genes, Paf1C may also act independently of H2Bub deposition or occupy these genes more stable than H2Bub marking, possibly reflecting the dynamic nature of Paf1C association and H2Bub turnover during transcription.
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Affiliation(s)
- Noel Blanco-Touriñán
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), 46022 Valencia, Spain
| | - Jaime Pérez-Alemany
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), 46022 Valencia, Spain
| | - Clara Bourbousse
- Ecole Normale Supérieure, Institut de Biologie de l'Ecole Normale Supérieure (CNRS), CNRS, INSERM, Université PSL, 75230 Paris, France
| | - David Latrasse
- Institute of Plant Sciences Paris-Saclay (Université Paris-Saclay-CNRS), 91190 Gif-sur-Yvette, France
| | - Ouardia Ait-Mohamed
- Ecole Normale Supérieure, Institut de Biologie de l'Ecole Normale Supérieure (CNRS), CNRS, INSERM, Université PSL, 75230 Paris, France
| | - Moussa Benhamed
- Institute of Plant Sciences Paris-Saclay (Université Paris-Saclay-CNRS), 91190 Gif-sur-Yvette, France
| | - Fredy Barneche
- Ecole Normale Supérieure, Institut de Biologie de l'Ecole Normale Supérieure (CNRS), CNRS, INSERM, Université PSL, 75230 Paris, France
| | - Miguel A Blázquez
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), 46022 Valencia, Spain
| | | | - David Alabadí
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), 46022 Valencia, Spain
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30
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Francette AM, Arndt KM. Multiple direct and indirect roles of Paf1C in elongation, splicing, and histone post-translational modifications. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.25.591159. [PMID: 38712269 PMCID: PMC11071476 DOI: 10.1101/2024.04.25.591159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Paf1C is a highly conserved protein complex with critical functions during eukaryotic transcription. Previous studies have shown that Paf1C is multi-functional, controlling specific aspects of transcription, ranging from RNAPII processivity to histone modifications. However, it is unclear how specific Paf1C subunits directly impact transcription and coupled processes. We have compared conditional depletion to steady-state deletion for each Paf1C subunit to determine the direct and indirect contributions to gene expression in Saccharomyces cerevisiae. Using nascent transcript sequencing, RNAPII profiling, and modeling of transcription elongation dynamics, we have demonstrated direct effects of Paf1C subunits on RNAPII processivity and elongation rate and indirect effects on transcript splicing and repression of antisense transcripts. Further, our results suggest that the direct transcriptional effects of Paf1C cannot be readily assigned to any particular histone modification. This work comprehensively analyzes both the immediate and extended roles of each Paf1C subunit in transcription elongation and transcript regulation.
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Affiliation(s)
- Alex M. Francette
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, 15260, USA
| | - Karen M. Arndt
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, 15260, USA
- Lead contact
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31
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Yu P, Xu T, Ma W, Fang X, Bao Y, Xu C, Huang J, Sun Y, Li G. PRMT6-mediated transcriptional activation of ythdf2 promotes glioblastoma migration, invasion, and emt via the wnt-β-catenin pathway. J Exp Clin Cancer Res 2024; 43:116. [PMID: 38637831 PMCID: PMC11025288 DOI: 10.1186/s13046-024-03038-3] [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: 12/24/2023] [Accepted: 04/04/2024] [Indexed: 04/20/2024] Open
Abstract
BACKGROUND Protein arginine methyltransferase 6 (PRMT6) plays a crucial role in various pathophysiological processes and diseases. Glioblastoma (GBM; WHO Grade 4 glioma) is the most common and lethal primary brain tumor in adults, with a prognosis that is extremely poor, despite being less common than other systemic malignancies. Our current research finds PRMT6 upregulated in GBM, enhancing tumor malignancy. Yet, the specifics of PRMT6's regulatory processes and potential molecular mechanisms in GBM remain largely unexplored. METHODS PRMT6's expression and prognostic significance in GBM were assessed using glioma public databases, immunohistochemistry (IHC), and immunoblotting. Scratch and Transwell assays examined GBM cell migration and invasion. Immunoblotting evaluated the expression of epithelial-mesenchymal transition (EMT) and Wnt-β-catenin pathway-related proteins. Dual-luciferase reporter assays and ChIP-qPCR assessed the regulatory relationship between PRMT6 and YTHDF2. An in situ tumor model in nude mice evaluated in vivo conditions. RESULTS Bioinformatics analysis indicates high expression of PRMT6 and YTHDF2 in GBM, correlating with poor prognosis. Functional experiments show PRMT6 and YTHDF2 promote GBM migration, invasion, and EMT. Mechanistic experiments reveal PRMT6 and CDK9 co-regulate YTHDF2 expression. YTHDF2 binds and promotes the degradation of negative regulators APC and GSK3β mRNA of the Wnt-β-catenin pathway, activating it and consequently enhancing GBM malignancy. CONCLUSIONS Our results demonstrate the PRMT6-YTHDF2-Wnt-β-Catenin axis promotes GBM migration, invasion, and EMT in vitro and in vivo, potentially serving as a therapeutic target for GBM.
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Affiliation(s)
- Peng Yu
- Department of Neurosurgery, the First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning, 110001, China
| | - Tutu Xu
- Department of Neurosurgery, the First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning, 110001, China
| | - Wenmeng Ma
- Department of Immunology, Basic Medicine College, China Medical University, Shenyang, Liaoning, China
| | - Xiang Fang
- Department of Neurosurgery, the First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning, 110001, China
- Department of Neurosurgery, Central hospital affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Yue Bao
- Department of Neurosurgery, Qingdao Municipal Hospital, Qingdao, Shandong, China
| | - Chengran Xu
- Department of Neurosurgery, the First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning, 110001, China
| | - Jinhai Huang
- Department of Neurosurgery, the First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning, 110001, China
| | - Yongqing Sun
- Department of Neurosurgery, the First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning, 110001, China
| | - Guangyu Li
- Department of Neurosurgery, the First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning, 110001, China.
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32
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Santana JF, Spector BM, Suarez G, Luse D, Price D. NELF focuses sites of initiation and maintains promoter architecture. Nucleic Acids Res 2024; 52:2977-2994. [PMID: 38197272 PMCID: PMC11014283 DOI: 10.1093/nar/gkad1253] [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: 09/26/2023] [Revised: 11/29/2023] [Accepted: 12/20/2023] [Indexed: 01/11/2024] Open
Abstract
Many factors control the elongation phase of transcription by RNA polymerase II (Pol II), a process that plays an essential role in regulating gene expression. We utilized cells expressing degradation tagged subunits of NELFB, PAF1 and RTF1 to probe the effects of depletion of the factors on nascent transcripts using PRO-Seq and on chromatin architecture using DFF-ChIP. Although NELF is involved in promoter proximal pausing, depletion of NELFB had only a minimal effect on the level of paused transcripts and almost no effect on control of productive elongation. Instead, NELF depletion increased the utilization of downstream transcription start sites and caused a dramatic, genome-wide loss of H3K4me3 marked nucleosomes. Depletion of PAF1 and RTF1 both had major effects on productive transcript elongation in gene bodies and also caused initiation site changes like those seen with NELFB depletion. Our study confirmed that the first nucleosome encountered during initiation and early elongation is highly positioned with respect to the major TSS. In contrast, the positions of H3K4me3 marked nucleosomes in promoter regions are heterogeneous and are influenced by transcription. We propose a model defining NELF function and a general role of the H3K4me3 modification in blocking transcription initiation.
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Affiliation(s)
- Juan F Santana
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Benjamin M Spector
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Gustavo A Suarez
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Donal S Luse
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - David H Price
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
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33
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Mbonye U, Karn J. The cell biology of HIV-1 latency and rebound. Retrovirology 2024; 21:6. [PMID: 38580979 PMCID: PMC10996279 DOI: 10.1186/s12977-024-00639-w] [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] [Indexed: 04/07/2024] Open
Abstract
Transcriptionally latent forms of replication-competent proviruses, present primarily in a small subset of memory CD4+ T cells, pose the primary barrier to a cure for HIV-1 infection because they are the source of the viral rebound that almost inevitably follows the interruption of antiretroviral therapy. Over the last 30 years, many of the factors essential for initiating HIV-1 transcription have been identified in studies performed using transformed cell lines, such as the Jurkat T-cell model. However, as highlighted in this review, several poorly understood mechanisms still need to be elucidated, including the molecular basis for promoter-proximal pausing of the transcribing complex and the detailed mechanism of the delivery of P-TEFb from 7SK snRNP. Furthermore, the central paradox of HIV-1 transcription remains unsolved: how are the initial rounds of transcription achieved in the absence of Tat? A critical limitation of the transformed cell models is that they do not recapitulate the transitions between active effector cells and quiescent memory T cells. Therefore, investigation of the molecular mechanisms of HIV-1 latency reversal and LRA efficacy in a proper physiological context requires the utilization of primary cell models. Recent mechanistic studies of HIV-1 transcription using latently infected cells recovered from donors and ex vivo cellular models of viral latency have demonstrated that the primary blocks to HIV-1 transcription in memory CD4+ T cells are restrictive epigenetic features at the proviral promoter, the cytoplasmic sequestration of key transcription initiation factors such as NFAT and NF-κB, and the vanishingly low expression of the cellular transcription elongation factor P-TEFb. One of the foremost schemes to eliminate the residual reservoir is to deliberately reactivate latent HIV-1 proviruses to enable clearance of persisting latently infected cells-the "Shock and Kill" strategy. For "Shock and Kill" to become efficient, effective, non-toxic latency-reversing agents (LRAs) must be discovered. Since multiple restrictions limit viral reactivation in primary cells, understanding the T-cell signaling mechanisms that are essential for stimulating P-TEFb biogenesis, initiation factor activation, and reversing the proviral epigenetic restrictions have become a prerequisite for the development of more effective LRAs.
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Affiliation(s)
- Uri Mbonye
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
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34
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Su BG, Vos SM. Distinct negative elongation factor conformations regulate RNA polymerase II promoter-proximal pausing. Mol Cell 2024; 84:1243-1256.e5. [PMID: 38401543 PMCID: PMC10997474 DOI: 10.1016/j.molcel.2024.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 12/17/2023] [Accepted: 01/25/2024] [Indexed: 02/26/2024]
Abstract
Metazoan gene expression regulation involves pausing of RNA polymerase (Pol II) in the promoter-proximal region of genes and is stabilized by DSIF and NELF. Upon depletion of elongation factors, NELF appears to accompany elongating Pol II past pause sites; however, prior work indicates that NELF prevents Pol II elongation. Here, we report cryoelectron microscopy structures of Pol II-DSIF-NELF complexes with NELF in two distinct conformations corresponding to paused and poised states. The paused NELF state supports Pol II stalling, whereas the poised NELF state enables transcription elongation as it does not support a tilted RNA-DNA hybrid. Further, the poised NELF state can accommodate TFIIS binding to Pol II, allowing for Pol II reactivation at paused or backtracking sites. Finally, we observe that the NELF-A tentacle interacts with the RPB2 protrusion and is necessary for pausing. Our results define how NELF can support pausing, reactivation, and elongation by Pol II.
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Affiliation(s)
- Bonnie G Su
- Department of Biology, Massachusetts Institute of Technology, Building 68, 31 Ames St., Cambridge, MA 02139, USA
| | - Seychelle M Vos
- Department of Biology, Massachusetts Institute of Technology, Building 68, 31 Ames St., Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
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35
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Leydon AR, Downing B, Sanchez JS, Loll-Krippleber R, Belliveau NM, Rodriguez-Mias RA, Bauer A, Watson IJ, Bae L, Villén J, Brown GW, Nemhauser JL. A conserved function of corepressors is to nucleate assembly of the transcriptional preinitiation complex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.01.587599. [PMID: 38617365 PMCID: PMC11014602 DOI: 10.1101/2024.04.01.587599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
The plant corepressor TPL is recruited to diverse chromatin contexts, yet its mechanism of repression remains unclear. Previously, we have leveraged the fact that TPL retains its function in a synthetic transcriptional circuit in the yeast model Saccharomyces cerevisiae to localize repressive function to two distinct domains. Here, we employed two unbiased whole genome approaches to map the physical and genetic interactions of TPL at a repressed locus. We identified SPT4, SPT5 and SPT6 as necessary for repression with the SPT4 subunit acting as a bridge connecting TPL to SPT5 and SPT6. We also discovered the association of multiple additional constituents of the transcriptional preinitiation complex at TPL-repressed promoters, specifically those involved in early transcription initiation events. These findings were validated in yeast and plants through multiple assays, including a novel method to analyze conditional loss of function of essential genes in plants. Our findings support a model where TPL nucleates preassembly of the transcription activation machinery to facilitate rapid onset of transcription once repression is relieved.
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Affiliation(s)
| | - Benjamin Downing
- Department of Biology, University of Washington, Seattle, 98195, USA
| | | | | | | | | | - Andrew Bauer
- Department of Biology, University of Washington, Seattle, 98195, USA
| | | | - Lena Bae
- Department of Biology, University of Washington, Seattle, 98195, USA
| | - Judit Villén
- Department of Genome Sciences, University of Washington, Seattle, 98195, USA
| | - Grant W. Brown
- Department of Biochemistry and Donnelly Centre, University of Toronto, Toronto, Ontario, CA
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36
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Čermák V, Kašpar T, Fischer L. SPT6L, a newly discovered ancestral component of the plant RNA-directed DNA methylation pathway. FRONTIERS IN PLANT SCIENCE 2024; 15:1372880. [PMID: 38576781 PMCID: PMC10991848 DOI: 10.3389/fpls.2024.1372880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 02/20/2024] [Indexed: 04/06/2024]
Abstract
RNA-directed DNA methylation (RdDM) is driven by small RNAs (sRNAs) complementary to the nascent transcript of RNA polymerase V (Pol V). sRNAs associated with ARGONAUTE (AGO) proteins are tethered to Pol V mainly by the AGO-hook domain of its subunit NRPE1. We found, by in silico analyses, that Pol V strongly colocalizes on chromatin with another AGO-hook protein, SPT6-like (SPT6L), which is a known essential transcription elongation factor of Pol II. Our phylogenetic analysis revealed that SPT6L acquired its AGO-binding capacity already in the most basal streptophyte algae, even before the emergence of Pol V, suggesting that SPT6L might be a driving force behind the RdDM evolution. Since its emergence, SPT6L with the AGO-hook represents the only conserved SPT6 homolog in Viridiplantae, implying that the same protein is involved in both Pol II and Pol V complexes. To better understand the role of SPT6L in the Pol V complex, we characterized genomic loci where these two colocalize and uncovered that DNA methylation there is more dynamic, driven by higher levels of sRNAs often from non-canonical RdDM pathways and more dependent on chromatin modifying and remodeling proteins like MORC. Pol V loci with SPT6L are highly depleted in helitrons but enriched in gene promoters for which locally and temporally precise methylation is necessary. In view of these results, we discuss potential roles of multiple AGO-hook domains present in the Pol V complex and speculate that SPT6L mediates de novo methylation of naïve loci by interconnecting Pol II and Pol V activities.
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Affiliation(s)
- Vojtěch Čermák
- Laboratory of Plant Cell Biology and Biotechnology, Faculty of Science, Department of Experimental Plant Biology, Charles University, Prague, Czechia
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37
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Sekine SI, Ehara H, Kujirai T, Kurumizaka H. Structural perspectives on transcription in chromatin. Trends Cell Biol 2024; 34:211-224. [PMID: 37596139 DOI: 10.1016/j.tcb.2023.07.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 07/17/2023] [Accepted: 07/24/2023] [Indexed: 08/20/2023]
Abstract
In eukaryotes, all genetic processes take place in the cell nucleus, where DNA is packaged as chromatin in 'beads-on-a-string' nucleosome arrays. RNA polymerase II (RNAPII) transcribes protein-coding and many non-coding genes in this chromatin environment. RNAPII elongates RNA while passing through multiple nucleosomes and maintaining the integrity of the chromatin structure. Recent structural studies have shed light on the detailed mechanisms of this process, including how transcribing RNAPII progresses through a nucleosome and reassembles it afterwards, and how transcription elongation factors, chromatin remodelers, and histone chaperones participate in these processes. Other studies have also illuminated the crucial role of nucleosomes in preinitiation complex assembly and transcription initiation. In this review we outline these advances and discuss future perspectives.
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Affiliation(s)
- 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.
| | - Haruhiko Ehara
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Tomoya Kujirai
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan; Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Hitoshi Kurumizaka
- Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan; Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
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38
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Kokic G, Yakoub G, van den Heuvel D, Wondergem AP, van der Meer PJ, van der Weegen Y, Chernev A, Fianu I, Fokkens TJ, Lorenz S, Urlaub H, Cramer P, Luijsterburg MS. Structural basis for RNA polymerase II ubiquitylation and inactivation in transcription-coupled repair. Nat Struct Mol Biol 2024; 31:536-547. [PMID: 38316879 PMCID: PMC10948364 DOI: 10.1038/s41594-023-01207-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 12/21/2023] [Indexed: 02/07/2024]
Abstract
During transcription-coupled DNA repair (TCR), RNA polymerase II (Pol II) transitions from a transcriptionally active state to an arrested state that allows for removal of DNA lesions. This transition requires site-specific ubiquitylation of Pol II by the CRL4CSA ubiquitin ligase, a process that is facilitated by ELOF1 in an unknown way. Using cryogenic electron microscopy, biochemical assays and cell biology approaches, we found that ELOF1 serves as an adaptor to stably position UVSSA and CRL4CSA on arrested Pol II, leading to ligase neddylation and activation of Pol II ubiquitylation. In the presence of ELOF1, a transcription factor IIS (TFIIS)-like element in UVSSA gets ordered and extends through the Pol II pore, thus preventing reactivation of Pol II by TFIIS. Our results provide the structural basis for Pol II ubiquitylation and inactivation in TCR.
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Affiliation(s)
- Goran Kokic
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Division of Structural Biology and Protein Therapeutics, Odyssey Therapeutics GmbH, Frankfurt am Main, Germany
| | - George Yakoub
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Diana van den Heuvel
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Annelotte P Wondergem
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Paula J van der Meer
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Yana van der Weegen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Aleksandar Chernev
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Isaac Fianu
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Thornton J Fokkens
- Ubiquitin Signaling Specificity, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Sonja Lorenz
- Ubiquitin Signaling Specificity, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Bioanalytics Group, University Medical Center Göttingen, Institute of Clinical Chemistry, Göttingen, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
| | - Martijn S Luijsterburg
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
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39
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Gaballa A, Gebhardt-Wolf A, Krenz B, Mattavelli G, John M, Cossa G, Andreani S, Schülein-Völk C, Montesinos F, Vidal R, Kastner C, Ade CP, Kneitz B, Gasteiger G, Gallant P, Rosenfeldt M, Riedel A, Eilers M. PAF1c links S-phase progression to immune evasion and MYC function in pancreatic carcinoma. Nat Commun 2024; 15:1446. [PMID: 38365788 PMCID: PMC10873513 DOI: 10.1038/s41467-024-45760-8] [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: 09/23/2023] [Accepted: 02/05/2024] [Indexed: 02/18/2024] Open
Abstract
In pancreatic ductal adenocarcinoma (PDAC), endogenous MYC is required for S-phase progression and escape from immune surveillance. Here we show that MYC in PDAC cells is needed for the recruitment of the PAF1c transcription elongation complex to RNA polymerase and that depletion of CTR9, a PAF1c subunit, enables long-term survival of PDAC-bearing mice. PAF1c is largely dispensable for normal proliferation and regulation of MYC target genes. Instead, PAF1c limits DNA damage associated with S-phase progression by being essential for the expression of long genes involved in replication and DNA repair. Surprisingly, the survival benefit conferred by CTR9 depletion is not due to DNA damage, but to T-cell activation and restoration of immune surveillance. This is because CTR9 depletion releases RNA polymerase and elongation factors from the body of long genes and promotes the transcription of short genes, including MHC class I genes. The data argue that functionally distinct gene sets compete for elongation factors and directly link MYC-driven S-phase progression to tumor immune evasion.
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Affiliation(s)
- Abdallah Gaballa
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Anneli Gebhardt-Wolf
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Bastian Krenz
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Greta Mattavelli
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Mara John
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Giacomo Cossa
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Silvia Andreani
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Christina Schülein-Völk
- Core Unit High-Content Microscopy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Francisco Montesinos
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Raphael Vidal
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Carolin Kastner
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Carsten P Ade
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Burkhard Kneitz
- Department of Urology and Pediatric Urology, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Georg Gasteiger
- Würzburg Institute of Systems Immunology, Max Planck Research Group, Julius Maximilian University Würzburg, Versbacher Str. 9, 97078, Würzburg, Germany
| | - Peter Gallant
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Mathias Rosenfeldt
- Institute of Pathology, Julius Maximilian University Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Angela Riedel
- Mildred Scheel Early Career Center, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany
| | - Martin Eilers
- Department of Biochemistry and Molecular Biologyy, Theodor Boveri Institute, Biocenter, Julius Maximilian University Würzburg, Am Hubland, 97074, Würzburg, Germany.
- Comprehensive Cancer Center Mainfranken, University Hospital Würzburg, Josef-Schneider-Str. 2, 97080, Würzburg, Germany.
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40
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Chen Y, Cramer P. RNA polymerase II elongation factors use conserved regulatory mechanisms. Curr Opin Struct Biol 2024; 84:102766. [PMID: 38181687 DOI: 10.1016/j.sbi.2023.102766] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/11/2023] [Accepted: 12/13/2023] [Indexed: 01/07/2024]
Abstract
RNA polymerase II (Pol II) transcription is regulated by many elongation factors. Among these factors, TFIIF, PAF-RTF1, ELL and Elongin stimulate mRNA chain elongation by Pol II. Cryo-EM structures of Pol II complexes with these elongation factors now reveal some general principles on how elongation factors bind Pol II and how they stimulate transcription. All four elongation factors contact Pol II at domains external 2 and protrusion, whereas TFIIF and ELL additionally bind the Pol II lobe. All factors apparently stabilize cleft-flanking elements, whereas RTF1 and Elongin additionally approach the active site with a latch element and may influence catalysis or translocation. Due to the shared binding sites on Pol II, factor binding is mutually exclusive, and thus it remains to be studied what determines which elongation factors bind at a certain gene and under which condition.
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Affiliation(s)
- Ying Chen
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany.
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany.
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41
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Zhao J, Cato LD, Arora UP, Bao EL, Bryant SC, Williams N, Jia Y, Goldman SR, Nangalia J, Erb MA, Vos SM, Armstrong SA, Sankaran VG. Inherited blood cancer predisposition through altered transcription elongation. Cell 2024; 187:642-658.e19. [PMID: 38218188 PMCID: PMC10872907 DOI: 10.1016/j.cell.2023.12.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 11/26/2023] [Accepted: 12/08/2023] [Indexed: 01/15/2024]
Abstract
Despite advances in defining diverse somatic mutations that cause myeloid malignancies, a significant heritable component for these cancers remains largely unexplained. Here, we perform rare variant association studies in a large population cohort to identify inherited predisposition genes for these blood cancers. CTR9, which encodes a key component of the PAF1 transcription elongation complex, is among the significant genes identified. The risk variants found in the cases cause loss of function and result in a ∼10-fold increased odds of acquiring a myeloid malignancy. Partial CTR9 loss of function expands human hematopoietic stem cells (HSCs) by increased super elongation complex-mediated transcriptional activity, which thereby increases the expression of key regulators of HSC self-renewal. By following up on insights from a human genetic study examining inherited predisposition to the myeloid malignancies, we define a previously unknown antagonistic interaction between the PAF1 and super elongation complexes. These insights could enable targeted approaches for blood cancer prevention.
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Affiliation(s)
- Jiawei Zhao
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA; Center for Cancer Immunology, Faculty of Pharmaceutical Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences (CAS), Shenzhen, China.
| | - Liam D Cato
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Uma P Arora
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Erik L Bao
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Nicholas Williams
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK; UK and MRC-Wellcome Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Yuemeng Jia
- Harvard Stem Cell Institute, Cambridge, MA, USA; Stem Cell Program, Boston Children's Hospital, Boston, MA, USA; Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Seth R Goldman
- Nascent Transcriptomics Core, Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Jyoti Nangalia
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK; UK and MRC-Wellcome Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Michael A Erb
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Seychelle M Vos
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Scott A Armstrong
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Vijay G Sankaran
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA; Harvard Stem Cell Institute, Cambridge, MA, USA.
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42
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Aoki K, Nitta A, Igarashi A. NELF and PAF1C complexes are core transcriptional machineries controlling colon cancer stemness. Oncogene 2024; 43:566-577. [PMID: 38182897 PMCID: PMC10873196 DOI: 10.1038/s41388-023-02930-0] [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: 07/15/2023] [Revised: 12/01/2023] [Accepted: 12/20/2023] [Indexed: 01/07/2024]
Abstract
Mutations in APC, found in 80% of colon caner, enhance β-catenin stabilization, which is the initial step of colonic tumorigenesis. However, the core transcriptional mechanism underlying the induction of colon cancer stemness by stable β-catenin remains unclear. Here, we found that inducible inhibition of β-catenin suppressed elongation of Pol II and RNA polymerase-associated factor 1 complex (PAF1C) around the transcription start site (TSS) of LGR5. Moreover, stable β-catenin enhanced the formation of active Pol II complex cooperatively with CDC73 and CDK9 by facilitating the recruitment of DRB sensitivity-inducing factor (DSIF) and negative elongation factor (NELF) complexes to the Pol II complex. Subsequently, stable β-catenin facilitated the formation of the Pol II-DSIF-PAF1C complex, suggesting that stable β-catenin induces cancer stemness by stimulating active Pol II complex through NELF and PAF1C. Furthermore, NELF or PAF1C inhibition recapitulated the changes in cancer stemness-related gene expression induced by the inhibition of stable β-catenin and suppressed colon cancer stemness. Additionally, the chemical inhibition of CDK12 (a downstream transcription CDK of PAF1C) suppressed colon cancer stemness. These results suggest that NELF and PAF1C are the core transcriptional machineries that control expression of colon cancer stemness-inducing genes and may be therapeutic targets for colon cancer.
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Affiliation(s)
- Koji Aoki
- Department of Pharmacology, Faculty of Medicine, University of Fukui, Fukui, Japan.
| | - Akari Nitta
- Department of Pharmacology, Faculty of Medicine, University of Fukui, Fukui, Japan
| | - Ayumi Igarashi
- Department of Pharmacology, Faculty of Medicine, University of Fukui, Fukui, Japan
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43
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Kaye EG, Basavaraju K, Nelson GM, Zomer HD, Roy D, Joseph II, Rajabi-Toustani R, Qiao H, Adelman K, Reddi PP. RNA polymerase II pausing is essential during spermatogenesis for appropriate gene expression and completion of meiosis. Nat Commun 2024; 15:848. [PMID: 38287033 PMCID: PMC10824759 DOI: 10.1038/s41467-024-45177-3] [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: 05/01/2023] [Accepted: 01/16/2024] [Indexed: 01/31/2024] Open
Abstract
Male germ cell development requires precise regulation of gene activity in a cell-type and stage-specific manner, with perturbations in gene expression during spermatogenesis associated with infertility. Here, we use steady-state, nascent and single-cell RNA sequencing strategies to comprehensively characterize gene expression across male germ cell populations, to dissect the mechanisms of gene control and provide new insights towards therapy. We discover a requirement for pausing of RNA Polymerase II (Pol II) at the earliest stages of sperm differentiation to establish the landscape of gene activity across development. Accordingly, genetic knockout of the Pol II pause-inducing factor NELF in immature germ cells blocks differentiation to spermatids. Further, we uncover unanticipated roles for Pol II pausing in the regulation of meiosis during spermatogenesis, with the presence of paused Pol II associated with double-strand break (DSB) formation, and disruption of meiotic gene expression and DSB repair in germ cells lacking NELF.
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Affiliation(s)
- Emily G Kaye
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
| | - Kavyashree Basavaraju
- Department of Comparative Biosciences, University of Illinois Urbana-Champaign, Urbana, IL, 61802, USA
| | - Geoffrey M Nelson
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
| | - Helena D Zomer
- Department of Comparative Biosciences, University of Illinois Urbana-Champaign, Urbana, IL, 61802, USA
| | - Debarun Roy
- Department of Comparative Biosciences, University of Illinois Urbana-Champaign, Urbana, IL, 61802, USA
| | - Irene Infancy Joseph
- Department of Comparative Biosciences, University of Illinois Urbana-Champaign, Urbana, IL, 61802, USA
| | - Reza Rajabi-Toustani
- Department of Comparative Biosciences, University of Illinois Urbana-Champaign, Urbana, IL, 61802, USA
| | - Huanyu Qiao
- Department of Comparative Biosciences, University of Illinois Urbana-Champaign, Urbana, IL, 61802, USA
| | - Karen Adelman
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA.
| | - Prabhakara P Reddi
- Department of Comparative Biosciences, University of Illinois Urbana-Champaign, Urbana, IL, 61802, USA.
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44
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Dunn LEM, Birkenheuer CH, Baines JD. A Revision of Herpes Simplex Virus Type 1 Transcription: First, Repress; Then, Express. Microorganisms 2024; 12:262. [PMID: 38399666 PMCID: PMC10892140 DOI: 10.3390/microorganisms12020262] [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: 12/15/2023] [Revised: 01/22/2024] [Accepted: 01/24/2024] [Indexed: 02/25/2024] Open
Abstract
The herpes virus genome bears more than 80 strong transcriptional promoters. Upon entry into the host cell nucleus, these genes are transcribed in an orderly manner, producing five immediate-early (IE) gene products, including ICP0, ICP4, and ICP22, while non-IE genes are mostly silent. The IE gene products are necessary for the transcription of temporal classes following sequentially as early, leaky late, and true late. A recent analysis using precision nuclear run-on followed by deep sequencing (PRO-seq) has revealed an important step preceding all HSV-1 transcription. Specifically, the immediate-early proteins ICP4 and ICP0 enter the cell with the incoming genome to help preclude the nascent antisense, intergenic, and sense transcription of all viral genes. VP16, which is also delivered into the nucleus upon entry, almost immediately reverses this repression on IE genes. The resulting de novo expression of ICP4 and ICP22 further repress antisense, intergenic, and early and late viral gene transcription through different mechanisms before the sequential de-repression of these gene classes later in infection. This early repression, termed transient immediate-early protein-mediated repression (TIEMR), precludes unproductive, antisense, intergenic, and late gene transcription early in infection to ensure the efficient and orderly progression of the viral cascade.
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Affiliation(s)
- Laura E M Dunn
- Baker Institute for Animal Health, Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14850, USA
| | - Claire H Birkenheuer
- Baker Institute for Animal Health, Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14850, USA
| | - Joel D Baines
- Baker Institute for Animal Health, Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14850, USA
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45
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Sarsam RD, Xu J, Lahiri I, Gong W, Li Q, Oh J, Zhou Z, Hou P, Chong J, Hao N, Li S, Wang D, Leschziner AE. Elf1 promotes Rad26's interaction with lesion-arrested Pol II for transcription-coupled repair. Proc Natl Acad Sci U S A 2024; 121:e2314245121. [PMID: 38194460 PMCID: PMC10801861 DOI: 10.1073/pnas.2314245121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 11/27/2023] [Indexed: 01/11/2024] Open
Abstract
Transcription-coupled nucleotide excision repair (TC-NER) is a highly conserved DNA repair pathway that removes bulky lesions in the transcribed genome. Cockayne syndrome B protein (CSB), or its yeast ortholog Rad26, has been known for decades to play important roles in the lesion-recognition steps of TC-NER. Another conserved protein ELOF1, or its yeast ortholog Elf1, was recently identified as a core transcription-coupled repair factor. How Rad26 distinguishes between RNA polymerase II (Pol II) stalled at a DNA lesion or other obstacles and what role Elf1 plays in this process remains unknown. Here, we present cryo-EM structures of Pol II-Rad26 complexes stalled at different obstacles that show that Rad26 uses a common mechanism to recognize a stalled Pol II, with additional interactions when Pol II is arrested at a lesion. A cryo-EM structure of lesion-arrested Pol II-Rad26 bound to Elf1 revealed that Elf1 induces further interactions between Rad26 and a lesion-arrested Pol II. Biochemical and genetic data support the importance of the interplay between Elf1 and Rad26 in TC-NER initiation. Together, our results provide important mechanistic insights into how two conserved transcription-coupled repair factors, Rad26/CSB and Elf1/ELOF1, work together at the initial lesion recognition steps of transcription-coupled repair.
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Affiliation(s)
- Reta D. Sarsam
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA92093
| | - Jun Xu
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA92093
| | - Indrajit Lahiri
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA92093
| | - Wenzhi Gong
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA70803
| | - Qingrong Li
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA92093
| | - Juntaek Oh
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA92093
| | - Zhen Zhou
- Department of Molecular Biology, School of Biological Sciences, University of California San Diego, La Jolla, CA92093
| | - Peini Hou
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA92093
| | - Jenny Chong
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA92093
| | - Nan Hao
- Department of Molecular Biology, School of Biological Sciences, University of California San Diego, La Jolla, CA92093
| | - Shisheng Li
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA70803
| | - Dong Wang
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA92093
- Division of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA92093
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093
| | - Andres E. Leschziner
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA92093
- Department of Molecular Biology, School of Biological Sciences, University of California San Diego, La Jolla, CA92093
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46
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Cornejo KG, Venegas A, Sono MH, Door M, Gutierrez-Ruiz B, Karabedian LB, Nandi SG, Dykhuizen EC, Saha RN. Activity-assembled nBAF complex mediates rapid immediate early gene transcription by regulating RNA Polymerase II productive elongation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.30.573688. [PMID: 38234780 PMCID: PMC10793463 DOI: 10.1101/2023.12.30.573688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Signal-dependent RNA Polymerase II (Pol2) productive elongation is an integral component of gene transcription, including those of immediate early genes (IEGs) induced by neuronal activity. However, it remains unclear how productively elongating Pol2 overcome nucleosomal barriers. Using RNAi, three degraders, and several small molecule inhibitors, we show that the mammalian SWI/SNF complex of neurons (neuronal BAF, or nBAF) is required for activity-induced transcription of neuronal IEGs, including Arc . The nBAF complex facilitates promoter-proximal Pol2 pausing, signal-dependent Pol2 recruitment (loading), and importantly, mediates productive elongation in the gene body via interaction with the elongation complex and elongation-competent Pol2. Mechanistically, Pol2 elongation is mediated by activity-induced nBAF assembly (especially, ARID1A recruitment) and its ATPase activity. Together, our data demonstrate that the nBAF complex regulates several aspects of Pol2 transcription and reveal mechanisms underlying activity-induced Pol2 elongation. These findings may offer insights into human maladies etiologically associated with mutational interdiction of BAF functions.
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47
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Felgines L, Rymen B, Martins LM, Xu G, Matteoli C, Himber C, Zhou M, Eis J, Coruh C, Böhrer M, Kuhn L, Chicher J, Pandey V, Hammann P, Wohlschlegel J, Waltz F, Law JA, Blevins T. CLSY docking to Pol IV requires a conserved domain critical for small RNA biogenesis and transposon silencing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.26.573199. [PMID: 38234754 PMCID: PMC10793415 DOI: 10.1101/2023.12.26.573199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Eukaryotes must balance the need for gene transcription by RNA polymerase II (Pol II) against the danger of mutations caused by transposable element (TE) proliferation. In plants, these gene expression and TE silencing activities are divided between different RNA polymerases. Specifically, RNA polymerase IV (Pol IV), which evolved from Pol II, transcribes TEs to generate small interfering RNAs (siRNAs) that guide DNA methylation and block TE transcription by Pol II. While the Pol IV complex is recruited to TEs via SNF2-like CLASSY (CLSY) proteins, how Pol IV partners with the CLSYs remains unknown. Here we identified a conserved CYC-YPMF motif that is specific to Pol IV and is positioned on the complex exterior. Furthermore, we found that this motif is essential for the co-purification of all four CLSYs with Pol IV, but that only one CLSY is present in any given Pol IV complex. These findings support a "one CLSY per Pol IV" model where the CYC-YPMF motif acts as a CLSY-docking site. Indeed, mutations in and around this motif phenocopy pol iv null mutants. Together, these findings provide structural and functional insights into a critical protein feature that distinguishes Pol IV from other RNA polymerases, allowing it to promote genome stability by targeting TEs for silencing.
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48
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Tullius TW, Isaac RS, Ranchalis J, Dubocanin D, Churchman LS, Stergachis AB. RNA polymerases reshape chromatin and coordinate transcription on individual fibers. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573133. [PMID: 38187631 PMCID: PMC10769320 DOI: 10.1101/2023.12.22.573133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
During eukaryotic transcription, RNA polymerases must initiate and pause within a crowded, complex environment, surrounded by nucleosomes and other transcriptional activity. This environment creates a spatial arrangement along individual chromatin fibers ripe for both competition and coordination, yet these relationships remain largely unknown owing to the inherent limitations of traditional structural and sequencing methodologies. To address these limitations, we employed long-read chromatin fiber sequencing (Fiber-seq) to visualize RNA polymerases within their native chromatin context at single-molecule and near single-nucleotide resolution along up to 30 kb fibers. We demonstrate that Fiber-seq enables the identification of single-molecule RNA Polymerase (Pol) II and III transcription associated footprints, which, in aggregate, mirror bulk short-read sequencing-based measurements of transcription. We show that Pol II pausing destabilizes downstream nucleosomes, with frequently paused genes maintaining a short-term memory of these destabilized nucleosomes. Furthermore, we demonstrate pervasive direct coordination and anti-coordination between nearby Pol II genes, Pol III genes, transcribed enhancers, and insulator elements. This coordination is largely limited to spatially organized elements within 5 kb of each other, implicating short-range chromatin environments as a predominant determinant of coordinated polymerase initiation. Overall, transcription initiation reshapes surrounding nucleosome architecture and coordinates nearby transcriptional machinery along individual chromatin fibers.
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Affiliation(s)
- Thomas W Tullius
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - R Stefan Isaac
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Jane Ranchalis
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA
| | - Danilo Dubocanin
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA
| | - L Stirling Churchman
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Andrew B Stergachis
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA
- Department of Genome Sciences, University of Washington, Seattle, WA
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49
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Chen Y, Kokic G, Dienemann C, Dybkov O, Urlaub H, Cramer P. Structure of the transcribing RNA polymerase II-Elongin complex. Nat Struct Mol Biol 2023; 30:1925-1935. [PMID: 37932450 PMCID: PMC10716050 DOI: 10.1038/s41594-023-01138-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 09/26/2023] [Indexed: 11/08/2023]
Abstract
Elongin is a heterotrimeric elongation factor for RNA polymerase (Pol) II transcription that is conserved among metazoa. Here, we report three cryo-EM structures of human Elongin bound to transcribing Pol II. The structures show that Elongin subunit ELOA binds the RPB2 side of Pol II and anchors the ELOB-ELOC subunit heterodimer. ELOA contains a 'latch' that binds between the end of the Pol II bridge helix and funnel helices, thereby inducing a conformational change near the polymerase active center. The latch is required for the elongation-stimulatory activity of Elongin, but not for Pol II binding, indicating that Elongin functions by allosterically regulating the conformational mobility of the polymerase active center. Elongin binding to Pol II is incompatible with association of the super elongation complex, PAF1 complex and RTF1, which also contain an elongation-stimulatory latch element.
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Affiliation(s)
- Ying Chen
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Clinical Laboratory, Qilu Hospital of Shandong University, Jinan, China
| | - Goran Kokic
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Christian Dienemann
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Olexandr Dybkov
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- University Medical Center Göttingen, Institute of Clinical Chemistry, Bioanalytics Group, Göttingen, Germany
- Cluster of Excellence 'Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells' (MBExC), University of Göttingen, Göttingen, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
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50
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Obermeyer S, Schrettenbrunner L, Stöckl R, Schwartz U, Grasser K. Different elongation factors distinctly modulate RNA polymerase II transcription in Arabidopsis. Nucleic Acids Res 2023; 51:11518-11533. [PMID: 37819035 PMCID: PMC10681736 DOI: 10.1093/nar/gkad825] [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: 04/14/2023] [Revised: 08/24/2023] [Accepted: 09/21/2023] [Indexed: 10/13/2023] Open
Abstract
Various transcript elongation factors (TEFs) including modulators of RNA polymerase II (RNAPII) activity and histone chaperones tune the efficiency of transcription in the chromatin context. TEFs are involved in establishing gene expression patterns during growth and development in Arabidopsis, while little is known about the genomic distribution of the TEFs and the way they facilitate transcription. We have mapped the genome-wide occupancy of the elongation factors SPT4-SPT5, PAF1C and FACT, relative to that of elongating RNAPII phosphorylated at residues S2/S5 within the carboxyterminal domain. The distribution of SPT4-SPT5 along transcribed regions closely resembles that of RNAPII-S2P, while the occupancy of FACT and PAF1C is rather related to that of RNAPII-S5P. Under transcriptionally challenging heat stress conditions, mutant plants lacking the corresponding TEFs are differentially impaired in transcript synthesis. Strikingly, in plants deficient in PAF1C, defects in transcription across intron/exon borders are observed that are cumulative along transcribed regions. Upstream of transcriptional start sites, the presence of FACT correlates with nucleosomal occupancy. Under stress conditions FACT is particularly required for transcriptional upregulation and to promote RNAPII transcription through +1 nucleosomes. Thus, Arabidopsis TEFs are differently distributed along transcribed regions, and are distinctly required during transcript elongation especially upon transcriptional reprogramming.
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Affiliation(s)
- Simon Obermeyer
- Cell Biology & Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Lukas Schrettenbrunner
- Cell Biology & Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Richard Stöckl
- Cell Biology & Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Uwe Schwartz
- NGS Analysis Centre, Biology and Pre-Clinical Medicine, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Klaus D Grasser
- Cell Biology & Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
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