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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:S1097-2765(24)00400-3. [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] [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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2
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Pang H, Peng Y, Zhang R, Gao Z, Lai X, Li D, Zhao X, Wang Y, Pei H, Qiao B, Ji Y, Wu Q. A triggered DNA nanomachine with enzyme-free for the rapid detection of telomerase activity in a one-step method. Anal Chim Acta 2024; 1299:342420. [PMID: 38499416 DOI: 10.1016/j.aca.2024.342420] [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: 08/12/2023] [Revised: 01/08/2024] [Accepted: 02/26/2024] [Indexed: 03/20/2024]
Abstract
BACKGROUND Telomerase is considered a biomarker for the early diagnosis and clinical treatment of cancer. The rapid and sensitive detection of telomerase activity is crucial to biological research, clinical diagnosis, and drug development. However, the main obstacles facing the current telomerase activity assay are the cumbersome and time-consuming procedure, the easy degradation of the telomerase RNA template and the need for additional proteases. Therefore, it is necessary to construct a new method for the detection of telomerase activity with easy steps, efficient reaction and strong anti-interference ability. RESULTS Herein, an efficient, enzyme-free, economical, sensitive, fluorometric detection method for telomerase activity in one-step, named triggered-DNA (T-DNA) nanomachine, was created based on target-triggered DNAzyme-cleavage activity and catalytic molecular beacon (CMB). Telomerase served as a switch and extended few numbers of (TTAGGG)n repeat sequences to initiate the signal amplification in the T-DNA nanomachine, resulting in a strong fluorescent signal. The reaction was a one-step method with a shortened time of 1 h and a constant temperature of 37 °C, without the addition of any protease. It also sensitively distinguished telomerase activity in various cell lines. The T-DNA nanomachine offered a detection limit of 12 HeLa cells μL-1, 9 SK-Hep-1 cells μL-1 and 3 HuH-7 cells μL-1 with a linear correlation detection range of 0.39 × 102-6.25 × 102 HeLa cells μL-1 for telomerase activity. SIGNIFICANCE In conclusion, our study demonstrated that the triggered-DNA nanomachine fulfills the requirements for rapid detection of telomerase activity in one-step under isothermal and enzyme-free conditions with excellent specificity, and its simple and stable structure makes it ideal for complex systems. These findings indicated the application prospect of DNA nanomachines in clinical diagnostics and provided new insights into the field of DNA nanomachine-based bioanalysis.
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Affiliation(s)
- Huajie Pang
- The First Affiliated Hospital, Hainan Medical University, Haikou, 570102, China; The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China
| | - Yanan Peng
- The First Affiliated Hospital, Hainan Medical University, Haikou, 570102, China; The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China
| | - Rui Zhang
- The First Affiliated Hospital, Hainan Medical University, Haikou, 570102, China; The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China
| | - Zhijun Gao
- The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China
| | - Xiangde Lai
- The First Affiliated Hospital, Hainan Medical University, Haikou, 570102, China; The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China
| | - Dongxia Li
- The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China
| | - Xuan Zhao
- The First Affiliated Hospital, Hainan Medical University, Haikou, 570102, China; The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China
| | - Yuanyuan Wang
- The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China; Key Laboratory of Emergency and Trauma of Ministry of Education, Research Unit of Island Emergency Medicine, Chinese Academy of Medical Sciences (No. 2019RU013), Hainan Medical University, Haikou, 571199, China
| | - Hua Pei
- The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China
| | - Bin Qiao
- The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China; Key Laboratory of Emergency and Trauma of Ministry of Education, Research Unit of Island Emergency Medicine, Chinese Academy of Medical Sciences (No. 2019RU013), Hainan Medical University, Haikou, 571199, China.
| | - Yuxiang Ji
- The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China; Key Laboratory of Tropical Translational Medicine of Ministry of Education, NHC Key Laboratory of Tropical Disease Control, Hainan Medical University, Haikou, 571199, China.
| | - Qiang Wu
- The First Affiliated Hospital, Hainan Medical University, Haikou, 570102, China; The Second Affiliated Hospital, School of Tropical Medicine, Hainan Medical University, Haikou, 570311, China; Key Laboratory of Emergency and Trauma of Ministry of Education, Research Unit of Island Emergency Medicine, Chinese Academy of Medical Sciences (No. 2019RU013), Hainan Medical University, Haikou, 571199, China.
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3
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Kolonay DW, Sattler KM, Strawser C, Rafael-Fortney J, Mihaylova MM, Miller KE, Lepper C, Baskin KK. Temporal regulation of the Mediator complex during muscle proliferation, differentiation, regeneration, aging, and disease. Front Cell Dev Biol 2024; 12:1331563. [PMID: 38690566 PMCID: PMC11058648 DOI: 10.3389/fcell.2024.1331563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 03/26/2024] [Indexed: 05/02/2024] Open
Abstract
Genesis of skeletal muscle relies on the differentiation and fusion of mono-nucleated muscle progenitor cells into the multi-nucleated muscle fiber syncytium. The temporally-controlled cellular and morphogenetic changes underlying this process are initiated by a series of highly coordinated transcription programs. At the core, the myogenic differentiation cascade is driven by muscle-specific transcription factors, i.e., the Myogenic Regulatory Factors (MRFs). Despite extensive knowledge on the function of individual MRFs, very little is known about how they are coordinated. Ultimately, highly specific coordination of these transcription programs is critical for their masterfully timed transitions, which in turn facilitates the intricate generation of skeletal muscle fibers from a naïve pool of progenitor cells. The Mediator complex links basal transcriptional machinery and transcription factors to regulate transcription and could be the integral component that coordinates transcription factor function during muscle differentiation, growth, and maturation. In this study, we systematically deciphered the changes in Mediator complex subunit expression in skeletal muscle development, regeneration, aging, and disease. We incorporated our in vitro and in vivo experimental results with analysis of publicly available RNA-seq and single nuclei RNA-seq datasets and uncovered the regulation of Mediator subunits in different physiological and temporal contexts. Our experimental results revealed that Mediator subunit expression during myogenesis is highly dynamic. We also discovered unique temporal patterns of Mediator expression in muscle stem cells after injury and during the early regeneration period, suggesting that Mediator subunits may have unique contributions to directing muscle stem cell fate. Although we observed few changes in Mediator subunit expression in aging muscles compared to younger muscles, we uncovered extensive heterogeneity of Mediator subunit expression in dystrophic muscle nuclei, characteristic of chronic muscle degeneration and regeneration cycles. Taken together, our study provides a glimpse of the complex regulation of Mediator subunit expression in the skeletal muscle cell lineage and serves as a springboard for mechanistic studies into the function of individual Mediator subunits in skeletal muscle.
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Affiliation(s)
- Dominic W. Kolonay
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Kristina M. Sattler
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Corinne Strawser
- Department of Pediatrics, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, United States
| | - Jill Rafael-Fortney
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Maria M. Mihaylova
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- The Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH, United States
| | - Katherine E. Miller
- Department of Pediatrics, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH, United States
| | - Christoph Lepper
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Kedryn K. Baskin
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
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4
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Yao Z, Song P, Jiao W. Pathogenic role of super-enhancers as potential therapeutic targets in lung cancer. Front Pharmacol 2024; 15:1383580. [PMID: 38681203 PMCID: PMC11047458 DOI: 10.3389/fphar.2024.1383580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 04/02/2024] [Indexed: 05/01/2024] Open
Abstract
Lung cancer is still one of the deadliest malignancies today, and most patients with advanced lung cancer pass away from disease progression that is uncontrollable by medications. Super-enhancers (SEs) are large clusters of enhancers in the genome's non-coding sequences that actively trigger transcription. Although SEs have just been identified over the past 10 years, their intricate structure and crucial role in determining cell identity and promoting tumorigenesis and progression are increasingly coming to light. Here, we review the structural composition of SEs, the auto-regulatory circuits, the control mechanisms of downstream genes and pathways, and the characterization of subgroups classified according to SEs in lung cancer. Additionally, we discuss the therapeutic targets, several small-molecule inhibitors, and available treatment options for SEs in lung cancer. Combination therapies have demonstrated considerable advantages in preclinical models, and we anticipate that these drugs will soon enter clinical studies and benefit patients.
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Affiliation(s)
- Zhiyuan Yao
- Department of Thoracic Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Peng Song
- Department of Thoracic Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Wenjie Jiao
- Department of Thoracic Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
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5
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Konuma T, Zhou MM. Distinct Histone H3 Lysine 27 Modifications Dictate Different Outcomes of Gene Transcription. J Mol Biol 2024; 436:168376. [PMID: 38056822 DOI: 10.1016/j.jmb.2023.168376] [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: 09/29/2023] [Revised: 11/26/2023] [Accepted: 11/27/2023] [Indexed: 12/08/2023]
Abstract
Site-specific histone modifications have long been recognized to play an important role in directing gene transcription in chromatin in biology of health and disease. However, concrete illustration of how different histone modifications in a site-specific manner dictate gene transcription outcomes, as postulated in the influential "Histone code hypothesis", introduced by Allis and colleagues in 2000, has been lacking. In this review, we summarize our latest understanding of the dynamic regulation of gene transcriptional activation, silence, and repression in chromatin that is directed distinctively by histone H3 lysine 27 acetylation, methylation, and crotonylation, respectively. This represents a special example of a long-anticipated verification of the "Histone code hypothesis."
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Affiliation(s)
- Tsuyoshi Konuma
- Graduate School of Medical Life Science, Yokohama 230-0045, Japan; School of Science, Yokohama City University, Yokohama 230-0045, Japan
| | - Ming-Ming Zhou
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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6
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Kaur J, Sharma A, Passi G, Dey P, Khajuria A, Alajangi HK, Jaiswal PK, Barnwal RP, Singh G. Nanomedicine at the Pulmonary Frontier: Immune-Centric Approaches for Respiratory Disease Treatment. Immunol Invest 2024; 53:295-347. [PMID: 38206610 DOI: 10.1080/08820139.2023.2298398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Respiratory diseases (RD) are a group of common ailments with a rapidly increasing global prevalence, posing a significant threat to humanity, especially the elderly population, and imposing a substantial burden on society and the economy. RD represents an unmet medical need that requires the development of viable pharmacotherapies. While various promising strategies have been devised to advance potential treatments for RD, their implementation has been hindered by difficulties in drug delivery, particularly in critically ill patients. Nanotechnology offers innovative solutions for delivering medications to the inflamed organ sites, such as the lungs. Although this approach is enticing, delivering nanomedicine to the lungs presents complex challenges that require sophisticated techniques. In this context, we review the potential of novel nanomedicine-based immunomodulatory strategies that could offer therapeutic benefits in managing this pressing health condition.
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Affiliation(s)
- Jatinder Kaur
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
| | - Akanksha Sharma
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
- Department of Biophysics, Panjab University, Chandigarh, India
| | - Gautam Passi
- Department of Biophysics, Panjab University, Chandigarh, India
| | - Piyush Dey
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
- Department of Biophysics, Panjab University, Chandigarh, India
| | - Akhil Khajuria
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
| | - Hema Kumari Alajangi
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
- Department of Biophysics, Panjab University, Chandigarh, India
| | - Pradeep Kumar Jaiswal
- Department of Biochemistry and Biophysics, Texas A & M University, College Station, Texas, USA
| | | | - Gurpal Singh
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, India
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7
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Russo M, Gualdrini F, Vallelonga V, Prosperini E, Noberini R, Pedretti S, Borriero C, Di Chiaro P, Polletti S, Imperato G, Marenda M, Ghirardi C, Bedin F, Cuomo A, Rodighiero S, Bonaldi T, Mitro N, Ghisletti S, Natoli G. Acetyl-CoA production by Mediator-bound 2-ketoacid dehydrogenases boosts de novo histone acetylation and is regulated by nitric oxide. Mol Cell 2024; 84:967-980.e10. [PMID: 38242130 PMCID: PMC7615796 DOI: 10.1016/j.molcel.2023.12.033] [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: 03/24/2023] [Revised: 12/08/2023] [Accepted: 12/21/2023] [Indexed: 01/21/2024]
Abstract
Histone-modifying enzymes depend on the availability of cofactors, with acetyl-coenzyme A (CoA) being required for histone acetyltransferase (HAT) activity. The discovery that mitochondrial acyl-CoA-producing enzymes translocate to the nucleus suggests that high concentrations of locally synthesized metabolites may impact acylation of histones and other nuclear substrates, thereby controlling gene expression. Here, we show that 2-ketoacid dehydrogenases are stably associated with the Mediator complex, thus providing a local supply of acetyl-CoA and increasing the generation of hyper-acetylated histone tails. Nitric oxide (NO), which is produced in large amounts in lipopolysaccharide-stimulated macrophages, inhibited the activity of Mediator-associated 2-ketoacid dehydrogenases. Elevation of NO levels and the disruption of Mediator complex integrity both affected de novo histone acetylation within a shared set of genomic regions. Our findings indicate that the local supply of acetyl-CoA generated by 2-ketoacid dehydrogenases bound to Mediator is required to maximize acetylation of histone tails at sites of elevated HAT activity.
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Affiliation(s)
- Marta Russo
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy.
| | - Francesco Gualdrini
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy.
| | - Veronica Vallelonga
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Elena Prosperini
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Roberta Noberini
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Silvia Pedretti
- DiSFeB, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano 20133, Italy
| | - Carolina Borriero
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Pierluigi Di Chiaro
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Sara Polletti
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Gabriele Imperato
- DiSFeB, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano 20133, Italy
| | - Mattia Marenda
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Chiara Ghirardi
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Fabio Bedin
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Alessandro Cuomo
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Simona Rodighiero
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy
| | - Tiziana Bonaldi
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy; Department of Hematology and Hematology-Oncology (DIPO), Università degli Studi di Milano, Milano 20122, Italy
| | - Nico Mitro
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy; DiSFeB, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano 20133, Italy
| | - Serena Ghisletti
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy.
| | - Gioacchino Natoli
- Department of Experimental Oncology, European Institute of Oncology (IEO) IRCCS, Milan 20139, Italy.
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8
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Yang JH, Hansen AS. Enhancer selectivity in space and time: from enhancer-promoter interactions to promoter activation. Nat Rev Mol Cell Biol 2024:10.1038/s41580-024-00710-6. [PMID: 38413840 DOI: 10.1038/s41580-024-00710-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2024] [Indexed: 02/29/2024]
Abstract
The primary regulators of metazoan gene expression are enhancers, originally functionally defined as DNA sequences that can activate transcription at promoters in an orientation-independent and distance-independent manner. Despite being crucial for gene regulation in animals, what mechanisms underlie enhancer selectivity for promoters, and more fundamentally, how enhancers interact with promoters and activate transcription, remain poorly understood. In this Review, we first discuss current models of enhancer-promoter interactions in space and time and how enhancers affect transcription activation. Next, we discuss different mechanisms that mediate enhancer selectivity, including repression, biochemical compatibility and regulation of 3D genome structure. Through 3D polymer simulations, we illustrate how the ability of 3D genome folding mechanisms to mediate enhancer selectivity strongly varies for different enhancer-promoter interaction mechanisms. Finally, we discuss how recent technical advances may provide new insights into mechanisms of enhancer-promoter interactions and how technical biases in methods such as Hi-C and Micro-C and imaging techniques may affect their interpretation.
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Affiliation(s)
- Jin H Yang
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Cambridge, MA, USA
| | - Anders S Hansen
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Koch Institute for Integrative Cancer Research, Cambridge, MA, USA.
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9
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Chen X, Xu Y. Interplay between the transcription preinitiation complex and the +1 nucleosome. Trends Biochem Sci 2024; 49:145-155. [PMID: 38218671 DOI: 10.1016/j.tibs.2023.12.001] [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: 08/18/2023] [Revised: 11/27/2023] [Accepted: 12/01/2023] [Indexed: 01/15/2024]
Abstract
Eukaryotic transcription starts with the assembly of a preinitiation complex (PIC) on core promoters. Flanking this region is the +1 nucleosome, the first nucleosome downstream of the core promoter. While this nucleosome is rich in epigenetic marks and plays a key role in transcription regulation, how the +1 nucleosome interacts with the transcription machinery has been a long-standing question. Here, we summarize recent structural and functional studies of the +1 nucleosome in complex with the PIC. We specifically focus on how differently organized promoter-nucleosome templates affect the assembly of the PIC and PIC-Mediator on chromatin and result in distinct transcription initiation.
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Affiliation(s)
- Xizi Chen
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China.
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10
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Crawford T, Siebler L, Sulkowska A, Nowack B, Jiang L, Pan Y, Lämke J, Kappel C, Bäurle I. The Mediator kinase module enhances polymerase activity to regulate transcriptional memory after heat stress in Arabidopsis. EMBO J 2024; 43:437-461. [PMID: 38228917 PMCID: PMC10897291 DOI: 10.1038/s44318-023-00024-x] [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: 05/26/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 01/18/2024] Open
Abstract
Plants are often exposed to recurring adverse environmental conditions in the wild. Acclimation to high temperatures entails transcriptional responses, which prime plants to better withstand subsequent stress events. Heat stress (HS)-induced transcriptional memory results in more efficient re-induction of transcription upon recurrence of heat stress. Here, we identified CDK8 and MED12, two subunits of the kinase module of the transcription co-regulator complex, Mediator, as promoters of heat stress memory and associated histone modifications in Arabidopsis. CDK8 is recruited to heat-stress memory genes by HEAT SHOCK TRANSCRIPTION FACTOR A2 (HSFA2). Like HSFA2, CDK8 is largely dispensable for the initial gene induction upon HS, and its function in transcriptional memory is thus independent of primary gene activation. In addition to the promoter and transcriptional start region of target genes, CDK8 also binds their 3'-region, where it may promote elongation, termination, or rapid re-initiation of RNA polymerase II (Pol II) complexes during transcriptional memory bursts. Our work presents a complex role for the Mediator kinase module during transcriptional memory in multicellular eukaryotes, through interactions with transcription factors, chromatin modifications, and promotion of Pol II efficiency.
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Affiliation(s)
- Tim Crawford
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Lara Siebler
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | | | - Bryan Nowack
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Li Jiang
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Yufeng Pan
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Jörn Lämke
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Christian Kappel
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Isabel Bäurle
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany.
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11
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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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12
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Chen X, Liu W, Wang Q, Wang X, Ren Y, Qu X, Li W, Xu Y. Structural visualization of transcription initiation in action. Science 2023; 382:eadi5120. [PMID: 38127763 DOI: 10.1126/science.adi5120] [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: 05/01/2023] [Accepted: 11/11/2023] [Indexed: 12/23/2023]
Abstract
Transcription initiation is a complex process, and its mechanism is incompletely understood. We determined the structures of de novo transcribing complexes TC2 to TC17 with RNA polymerase II halted on G-less promoters when nascent RNAs reach 2 to 17 nucleotides in length, respectively. Connecting these structures generated a movie and a working model. As initially synthesized RNA grows, general transcription factors (GTFs) remain bound to the promoter and the transcription bubble expands. Nucleoside triphosphate (NTP)-driven RNA-DNA translocation and template-strand accumulation in a nearly sealed channel may promote the transition from initially transcribing complexes (ITCs) (TC2 to TC9) to early elongation complexes (EECs) (TC10 to TC17). Our study shows dynamic processes of transcription initiation and reveals why ITCs require GTFs and bubble expansion for initial RNA synthesis, whereas EECs need GTF dissociation from the promoter and bubble collapse for promoter escape.
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Affiliation(s)
- Xizi Chen
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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
| | - Weida Liu
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Xinxin Wang
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Yulei Ren
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Xuechun Qu
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Wanjun Li
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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, New Cornerstone Science Laboratory, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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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13
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Talukdar PD, Chatterji U. Transcriptional co-activators: emerging roles in signaling pathways and potential therapeutic targets for diseases. Signal Transduct Target Ther 2023; 8:427. [PMID: 37953273 PMCID: PMC10641101 DOI: 10.1038/s41392-023-01651-w] [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: 04/18/2023] [Revised: 08/27/2023] [Accepted: 09/10/2023] [Indexed: 11/14/2023] Open
Abstract
Specific cell states in metazoans are established by the symphony of gene expression programs that necessitate intricate synergic interactions between transcription factors and the co-activators. Deregulation of these regulatory molecules is associated with cell state transitions, which in turn is accountable for diverse maladies, including developmental disorders, metabolic disorders, and most significantly, cancer. A decade back most transcription factors, the key enablers of disease development, were historically viewed as 'undruggable'; however, in the intervening years, a wealth of literature validated that they can be targeted indirectly through transcriptional co-activators, their confederates in various physiological and molecular processes. These co-activators, along with transcription factors, have the ability to initiate and modulate transcription of diverse genes necessary for normal physiological functions, whereby, deregulation of such interactions may foster tissue-specific disease phenotype. Hence, it is essential to analyze how these co-activators modulate specific multilateral processes in coordination with other factors. The proposed review attempts to elaborate an in-depth account of the transcription co-activators, their involvement in transcription regulation, and context-specific contributions to pathophysiological conditions. This review also addresses an issue that has not been dealt with in a comprehensive manner and hopes to direct attention towards future research that will encompass patient-friendly therapeutic strategies, where drugs targeting co-activators will have enhanced benefits and reduced side effects. Additional insights into currently available therapeutic interventions and the associated constraints will eventually reveal multitudes of advanced therapeutic targets aiming for disease amelioration and good patient prognosis.
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Affiliation(s)
- Priyanka Dey Talukdar
- Cancer Research Laboratory, Department of Zoology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, 700019, West Bengal, India
| | - Urmi Chatterji
- Cancer Research Laboratory, Department of Zoology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, 700019, West Bengal, India.
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14
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Malik S, Roeder RG. Regulation of the RNA polymerase II pre-initiation complex by its associated coactivators. Nat Rev Genet 2023; 24:767-782. [PMID: 37532915 PMCID: PMC11088444 DOI: 10.1038/s41576-023-00630-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2023] [Indexed: 08/04/2023]
Abstract
The RNA polymerase II (Pol II) pre-initiation complex (PIC) is a critical node in eukaryotic transcription regulation, and its formation is the major rate-limiting step in transcriptional activation. Diverse cellular signals borne by transcriptional activators converge on this large, multiprotein assembly and are transduced via intermediary factors termed coactivators. Cryogenic electron microscopy, multi-omics and single-molecule approaches have recently offered unprecedented insights into both the structure and cellular functions of the PIC and two key PIC-associated coactivators, Mediator and TFIID. Here, we review advances in our understanding of how Mediator and TFIID interact with activators and affect PIC formation and function. We also discuss how their functions are influenced by their chromatin environment and selected cofactors. We consider how, through its multifarious interactions and functionalities, a Mediator-containing and TFIID-containing PIC can yield an integrated signal processing system with the flexibility to determine the unique temporal and spatial expression pattern of a given gene.
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Affiliation(s)
- Sohail Malik
- Laboratory of Biochemistry & Molecular Biology, The Rockefeller University, New York, NY, USA.
| | - Robert G Roeder
- Laboratory of Biochemistry & Molecular Biology, The Rockefeller University, New York, NY, USA
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15
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Ruoff R, Weber H, Wang Y, Huang H, Shapiro E, Fenyö D, Garabedian MJ. MED19 encodes two unique protein isoforms that confer prostate cancer growth under low androgen through distinct gene expression programs. Sci Rep 2023; 13:18227. [PMID: 37880276 PMCID: PMC10600210 DOI: 10.1038/s41598-023-45199-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 10/17/2023] [Indexed: 10/27/2023] Open
Abstract
MED19, a component of the mediator complex and a co-regulator of the androgen receptor (AR), is pivotal in prostate cancer cell proliferation. MED19 has two isoforms: a full-length "canonical" and a shorter "alternative" variant. Specific antibodies were developed to investigate these isoforms. Both exhibit similar expression in normal prostate development and adult prostate tissue, but the canonical isoform is elevated in prostate adenocarcinomas. Overexpression of canonical MED19 in LNCaP cells promotes growth under conditions of androgen deprivation in vitro and in vivo, mirroring earlier findings with alternative MED19-overexpressing LNCaP cells. Interestingly, alternative MED19 cells displayed strong colony formation in clonogenic assays under conditions of androgen deprivation, while canonical MED19 cells did not, suggesting distinct functional roles. These isoforms also modulated gene expression differently. Canonical MED19 triggered genes related to extracellular matrix remodeling while suppressing those involved in androgen-inactivating glucuronidation. In contrast, alternative MED19 elevated genes tied to cell movement and reduced those associated with cell adhesion and differentiation. The ratio of MED19 isoform expression in prostate cancers shifts with the disease stage. Early-stage cancers exhibit higher canonical MED19 expression than alternative MED19, consistent with canonical MED19's ability to promote cell proliferation under androgen deprivation. Conversely, alternative MED19 levels were higher in later-stage metastatic prostate cancer than in canonical MED19, reflecting alternative MED19's capability to enhance cell migration and autonomous cell growth. Our findings suggest that MED19 isoforms play unique roles in prostate cancer progression and highlights MED19 as a potential therapeutic target for both early and late-stage prostate cancer.
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Affiliation(s)
- Rachel Ruoff
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Hannah Weber
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Ying Wang
- Institute for Systems Genetics, New York University Grossman School of Medicine, New York, NY, 10016, USA
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Hongying Huang
- Department of Urology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Ellen Shapiro
- Department of Urology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - David Fenyö
- Institute for Systems Genetics, New York University Grossman School of Medicine, New York, NY, 10016, USA
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Michael J Garabedian
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, 10016, USA.
- Department of Urology, New York University Grossman School of Medicine, New York, NY, 10016, USA.
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16
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Bernardini A, Hollinger C, Willgenss D, Müller F, Devys D, Tora L. Transcription factor IID parks and drives preinitiation complexes at sharp or broad promoters. Trends Biochem Sci 2023; 48:839-848. [PMID: 37574371 PMCID: PMC10529448 DOI: 10.1016/j.tibs.2023.07.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 07/19/2023] [Accepted: 07/19/2023] [Indexed: 08/15/2023]
Abstract
Core promoters are sites where transcriptional regulatory inputs of a gene are integrated to direct the assembly of the preinitiation complex (PIC) and RNA polymerase II (Pol II) transcription output. Until now, core promoter functions have been investigated by distinct methods, including Pol II transcription initiation site mappings and structural characterization of PICs on distinct promoters. Here, we bring together these previously unconnected observations and hypothesize how, on metazoan TATA promoters, the precisely structured building up of transcription factor (TF) IID-based PICs results in sharp transcription start site (TSS) selection; or, in contrast, how the less strictly controlled positioning of the TATA-less promoter DNA relative to TFIID-core PIC components results in alternative broad TSS selections by Pol II.
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Affiliation(s)
- Andrea Bernardini
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67404 Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, 67404 Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, 67404 Illkirch, France; Université de Strasbourg, 67404 Illkirch, France
| | | | | | - Ferenc Müller
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Didier Devys
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67404 Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, 67404 Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, 67404 Illkirch, France; Université de Strasbourg, 67404 Illkirch, France.
| | - László Tora
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67404 Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, 67404 Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, 67404 Illkirch, France; Université de Strasbourg, 67404 Illkirch, France.
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17
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Farnung L. Nucleosomes unwrapped: Structural perspectives on transcription through chromatin. Curr Opin Struct Biol 2023; 82:102690. [PMID: 37633188 DOI: 10.1016/j.sbi.2023.102690] [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: 06/14/2023] [Revised: 08/02/2023] [Accepted: 08/02/2023] [Indexed: 08/28/2023]
Abstract
Transcription of most protein-coding genes requires the passage of RNA polymerase II through chromatin. Chromatin with its fundamental unit, the nucleosome, represents a barrier to transcription. How RNA polymerase II and associated factors traverse through nucleosomes and how chromatin architecture is maintained have remained largely enigmatic. Only recently, cryo-EM structures have visualized the transcription process through chromatin. These structures have elucidated how transcription initiation and transcription elongation influence and are influenced by a chromatinized DNA substrate. This review provides a summary of our current structural understanding of transcription through chromatin, highlighting common mechanisms during nucleosomal traversal and novel regulatory mechanisms that have emerged in the last five years.
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Affiliation(s)
- Lucas Farnung
- Department of Cell Biology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
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18
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Yang DL, Huang K, Deng D, Zeng Y, Wang Z, Zhang Y. DNA-dependent RNA polymerases in plants. THE PLANT CELL 2023; 35:3641-3661. [PMID: 37453082 PMCID: PMC10533338 DOI: 10.1093/plcell/koad195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 06/09/2023] [Accepted: 05/29/2023] [Indexed: 07/18/2023]
Abstract
DNA-dependent RNA polymerases (Pols) transfer the genetic information stored in genomic DNA to RNA in all organisms. In eukaryotes, the typical products of nuclear Pol I, Pol II, and Pol III are ribosomal RNAs, mRNAs, and transfer RNAs, respectively. Intriguingly, plants possess two additional Pols, Pol IV and Pol V, which produce small RNAs and long noncoding RNAs, respectively, mainly for silencing transposable elements. The five plant Pols share some subunits, but their distinct functions stem from unique subunits that interact with specific regulatory factors in their transcription cycles. Here, we summarize recent advances in our understanding of plant nucleus-localized Pols, including their evolution, function, structures, and transcription cycles.
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Affiliation(s)
- Dong-Lei Yang
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Nanjing Agricultural University, Nanjing 210095, China
| | - Kun Huang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Deyin Deng
- State Key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang Agriculture and Forestry University, Lin’an, Hangzhou 311300, China
| | - Yuan Zeng
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Zhenxing Wang
- College of Horticulture, National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Nanjing Agricultural University, Nanjing 210095, China
| | - Yu Zhang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
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19
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Flores-Solis D, Lushpinskaia IP, Polyansky AA, Changiarath A, Boehning M, Mirkovic M, Walshe J, Pietrek LM, Cramer P, Stelzl LS, Zagrovic B, Zweckstetter M. Driving forces behind phase separation of the carboxy-terminal domain of RNA polymerase II. Nat Commun 2023; 14:5979. [PMID: 37749095 PMCID: PMC10519987 DOI: 10.1038/s41467-023-41633-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 09/10/2023] [Indexed: 09/27/2023] Open
Abstract
Eukaryotic gene regulation and pre-mRNA transcription depend on the carboxy-terminal domain (CTD) of RNA polymerase (Pol) II. Due to its highly repetitive, intrinsically disordered sequence, the CTD enables clustering and phase separation of Pol II. The molecular interactions that drive CTD phase separation and Pol II clustering are unclear. Here, we show that multivalent interactions involving tyrosine impart temperature- and concentration-dependent self-coacervation of the CTD. NMR spectroscopy, molecular ensemble calculations and all-atom molecular dynamics simulations demonstrate the presence of diverse tyrosine-engaging interactions, including tyrosine-proline contacts, in condensed states of human CTD and other low-complexity proteins. We further show that the network of multivalent interactions involving tyrosine is responsible for the co-recruitment of the human Mediator complex and CTD during phase separation. Our work advances the understanding of the driving forces of CTD phase separation and thus provides the basis to better understand CTD-mediated Pol II clustering in eukaryotic gene transcription.
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Affiliation(s)
- David Flores-Solis
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, 35075, Göttingen, Germany
| | - Irina P Lushpinskaia
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, 35075, Göttingen, Germany
| | - Anton A Polyansky
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Campus Vienna Biocenter 5, 1030, Vienna, Austria
- University of Vienna, Center for Molecular Biology, Department of Structural and Computational Biology, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - Arya Changiarath
- Faculty of Biology, Johannes Gutenberg University Mainz (JGU), Gresemundweg 2, 55128, Mainz, Germany
- KOMET1, Institute of Physics, Johannes Gutenberg University Mainz (JGU), Staudingerweg 9, 55099, Mainz, Germany
| | - Marc Boehning
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, 37077, Göttingen, Germany
| | - Milana Mirkovic
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Campus Vienna Biocenter 5, 1030, Vienna, Austria
- University of Vienna, Center for Molecular Biology, Department of Structural and Computational Biology, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - James Walshe
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, 37077, Göttingen, Germany
| | - Lisa M Pietrek
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Max-von-Laue Strasße 3, 60438, Frankfurt am Main, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, 37077, Göttingen, Germany
| | - Lukas S Stelzl
- Faculty of Biology, Johannes Gutenberg University Mainz (JGU), Gresemundweg 2, 55128, Mainz, Germany
- KOMET1, Institute of Physics, Johannes Gutenberg University Mainz (JGU), Staudingerweg 9, 55099, Mainz, Germany
- Institute of Molecular Biology (IMB), 55128, Mainz, Germany
| | - Bojan Zagrovic
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Campus Vienna Biocenter 5, 1030, Vienna, Austria
- University of Vienna, Center for Molecular Biology, Department of Structural and Computational Biology, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, 35075, Göttingen, Germany.
- Department of NMR-based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, 37077, Göttingen, Germany.
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20
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Schiano C, Luongo L, Maione S, Napoli C. Mediator complex in neurological disease. Life Sci 2023; 329:121986. [PMID: 37516429 DOI: 10.1016/j.lfs.2023.121986] [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: 02/13/2023] [Revised: 07/18/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
Neurological diseases, including traumatic brain injuries, stroke (haemorrhagic and ischemic), and inherent neurodegenerative diseases cause acquired disability in humans, representing a leading cause of death worldwide. The Mediator complex (MED) is a large, evolutionarily conserved multiprotein that facilities the interaction between transcription factors and RNA Polymerase II in eukaryotes. Some MED subunits have been found altered in the brain, although their specific functions in neurodegenerative diseases are not fully understood. Mutations in MED subunits were associated with a wide range of genetic diseases for MED12, MED13, MED13L, MED20, MED23, MED25, and CDK8 genes. In addition, MED12 and MED23 were deregulated in the Alzheimer's Disease. Interestingly, most of the genomic mutations have been found in the subunits of the kinase module. To date, there is only one evidence on MED1 involvement in post-stroke cognitive deficits. Although the underlying neurodegenerative disorders may be different, we are confident that the signal cascades of the biological-cognitive mechanisms of brain adaptation, which begin after brain deterioration, may also differ. Here, we analysed relevant studies in English published up to June 2023. They were identified through a search of electronic databases including PubMed, Medline, EMBASE and Scopus, including search terms such as "Mediator complex", "neurological disease", "brains". Thematic content analysis was conducted to collect and summarize all studies demonstrating MED alteration to understand the role of this central transcriptional regulatory complex in the brain. Improved and deeper knowledge of the regulatory mechanisms in neurological diseases can increase the ability of physicians to predict onset and progression, thereby improving diagnostic care and providing appropriate treatment decisions.
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Affiliation(s)
- Concetta Schiano
- Department of Advanced Medical and Surgical Sciences (DAMSS), University of Campania "Luigi Vanvitelli", Italy.
| | - Livio Luongo
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Italy; IRCSS, Neuromed, Pozzilli, Italy
| | - Sabatino Maione
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Italy; IRCSS, Neuromed, Pozzilli, Italy
| | - Claudio Napoli
- Department of Advanced Medical and Surgical Sciences (DAMSS), University of Campania "Luigi Vanvitelli", Italy; Clinical Department of Internal Medicine and Specialistic Units, Division of Clinical Immunology and Immunohematology, Transfusion Medicine, and Transplant Immunology (SIMT), Regional Reference Laboratory of Transplant Immunology (LIT), Azienda Universitaria Policlinico (AOU), Italy
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21
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Douaihy M, Topno R, Lagha M, Bertrand E, Radulescu O. BurstDECONV: a signal deconvolution method to uncover mechanisms of transcriptional bursting in live cells. Nucleic Acids Res 2023; 51:e88. [PMID: 37522372 PMCID: PMC10484743 DOI: 10.1093/nar/gkad629] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 06/23/2023] [Accepted: 07/17/2023] [Indexed: 08/01/2023] Open
Abstract
Monitoring transcription in living cells gives access to the dynamics of this complex fundamental process. It reveals that transcription is discontinuous, whereby active periods (bursts) are separated by one or several types of inactive periods of distinct lifetimes. However, decoding temporal fluctuations arising from live imaging and inferring the distinct transcriptional steps eliciting them is a challenge. We present BurstDECONV, a novel statistical inference method that deconvolves signal traces into individual transcription initiation events. We use the distribution of waiting times between successive polymerase initiation events to identify mechanistic features of transcription such as the number of rate-limiting steps and their kinetics. Comparison of our method to alternative methods emphasizes its advantages in terms of precision and flexibility. Unique features such as the direct determination of the number of promoter states and the simultaneous analysis of several potential transcription models make BurstDECONV an ideal analytic framework for live cell transcription imaging experiments. Using simulated realistic data, we found that our method is robust with regards to noise or suboptimal experimental designs. To show its generality, we applied it to different biological contexts such as Drosophila embryos or human cells.
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Affiliation(s)
- Maria Douaihy
- LPHI, University of Montpellier and CNRS, Place Eugène Bataillon, Montpellier 34095, France
- IGMM, University of Montpellier and CNRS, 1919 Rte de Mende, Montpellier 34090, France
| | - Rachel Topno
- LPHI, University of Montpellier and CNRS, Place Eugène Bataillon, Montpellier 34095, France
- IGH, University of Montpellier and CNRS, 141 Rue de la Cardonille, Montpellier 34094, France
| | - Mounia Lagha
- IGMM, University of Montpellier and CNRS, 1919 Rte de Mende, Montpellier 34090, France
| | - Edouard Bertrand
- IGH, University of Montpellier and CNRS, 141 Rue de la Cardonille, Montpellier 34094, France
| | - Ovidiu Radulescu
- LPHI, University of Montpellier and CNRS, Place Eugène Bataillon, Montpellier 34095, France
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22
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Rengachari S, Schilbach S, Cramer P. Mediator structure and function in transcription initiation. Biol Chem 2023; 404:829-837. [PMID: 37078249 DOI: 10.1515/hsz-2023-0158] [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: 03/10/2023] [Accepted: 04/06/2023] [Indexed: 04/21/2023]
Abstract
Recent advances in cryo-electron microscopy have led to multiple structures of Mediator in complex with the RNA polymerase II (Pol II) transcription initiation machinery. As a result we now hold in hands near-complete structures of both yeast and human Mediator complexes and have a better understanding of their interactions with the Pol II pre-initiation complex (PIC). Herein, we provide a summary of recent achievements and discuss their implications for future studies of Mediator and its role in gene regulation.
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Affiliation(s)
- Srinivasan Rengachari
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Sandra Schilbach
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077 Göttingen, Germany
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23
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Lushpinskaia IP, Flores-Solis D, Zweckstetter M. Structure and phase separation of the C-terminal domain of RNA polymerase II. Biol Chem 2023; 404:839-844. [PMID: 37331973 DOI: 10.1515/hsz-2023-0136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 06/01/2023] [Indexed: 06/20/2023]
Abstract
The repetitive heptads in the C-terminal domain (CTD) of RPB1, the largest subunit of RNA Polymerase II (Pol II), play a critical role in the regulation of Pol II-based transcription. Recent findings on the structure of the CTD in the pre-initiation complex determined by cryo-EM and the novel phase separation properties of key transcription components offers an expanded mechanistic interpretation of the spatiotemporal distribution of Pol II during transcription. Current experimental evidence further suggests an exquisite balance between CTD's local structure and an array of multivalent interactions that drive phase separation of Pol II and thus shape its transcriptional activity.
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Affiliation(s)
- Irina P Lushpinskaia
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, D-35075 Göttingen, Germany
| | - David Flores-Solis
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, D-35075 Göttingen, Germany
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold Straße 3A, D-35075 Göttingen, Germany
- Department of NMR-based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, D-37077 Göttingen, Germany
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24
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Ramasamy S, Aljahani A, Karpinska MA, Cao TBN, Velychko T, Cruz JN, Lidschreiber M, Oudelaar AM. The Mediator complex regulates enhancer-promoter interactions. Nat Struct Mol Biol 2023:10.1038/s41594-023-01027-2. [PMID: 37430065 DOI: 10.1038/s41594-023-01027-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 05/30/2023] [Indexed: 07/12/2023]
Abstract
Enhancer-mediated gene activation generally requires physical proximity between enhancers and their target gene promoters. However, the molecular mechanisms by which interactions between enhancers and promoters are formed are not well understood. Here, we investigate the function of the Mediator complex in the regulation of enhancer-promoter interactions, by combining rapid protein depletion and high-resolution MNase-based chromosome conformation capture approaches. We show that depletion of Mediator leads to reduced enhancer-promoter interaction frequencies, which are associated with a strong decrease in gene expression. In addition, we find increased interactions between CTCF-binding sites upon Mediator depletion. These changes in chromatin architecture are associated with a redistribution of the Cohesin complex on chromatin and a reduction in Cohesin occupancy at enhancers. Together, our results indicate that the Mediator and Cohesin complexes contribute to enhancer-promoter interactions and provide insights into the molecular mechanisms by which communication between enhancers and promoters is regulated.
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Affiliation(s)
- Shyam Ramasamy
- Genome Organization and Regulation, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Abrar Aljahani
- Genome Organization and Regulation, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Magdalena A Karpinska
- Genome Organization and Regulation, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - T B Ngoc Cao
- Genome Organization and Regulation, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Taras Velychko
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - J Neos Cruz
- Genome Organization and Regulation, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Michael Lidschreiber
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - A Marieke Oudelaar
- Genome Organization and Regulation, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
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25
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Cai R, Wang M, Liu M, Zhu X, Feng L, Yu Z, Yang X, Zhang Z, Guo H, Guo R, Zheng Y. An iRGD-conjugated photothermal therapy-responsive gold nanoparticle system carrying siCDK7 induces necroptosis and immunotherapeutic responses in lung adenocarcinoma. Bioeng Transl Med 2023; 8:e10430. [PMID: 37476070 PMCID: PMC10354770 DOI: 10.1002/btm2.10430] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/07/2022] [Accepted: 10/10/2022] [Indexed: 07/22/2023] Open
Abstract
Although immunotherapy has improved the clinical treatment of lung adenocarcinoma (LUAD), many tumors have poor responses to immunotherapy. In this study, we confirmed that high expression of Cyclin-Dependent Kinase 7 (CDK7) promoted an immunosuppressive macrophage phenotype and macrophage infiltration in LUAD. Thus, we have developed an internalizing-RGD (iRGD)-conjugated gold nanoparticle (AuNP) system which carries siCDK7 to activate the antitumor immune response. The iRGD-conjugated AuNP/siCDK7 system exhibited good tumor targeting performance and photothermal effects. The AuNP/siCDK7 system with excellent biosafety exerted a significant photothermal antitumor effect by inducing tumor cell necroptosis. Furthermore, the AuNP/siCDK7 system ameliorated the immunosuppressive microenvironment and enhanced the efficacy of anti-PD-1 treatment by increasing CD8+ T cell infiltration and decreasing M2 macrophage infiltration. Hence, this iRGD-conjugated AuNP/siCDK7 system is a potential treatment strategy for lung adenocarcinoma, which exerts its effects by triggering tumor cell necroptosis and immunotherapeutic responses.
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Affiliation(s)
- Rui Cai
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Meng Wang
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Meiyuan Liu
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Xiongjie Zhu
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Longbao Feng
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development, Department of Biomedical EngineeringJinan UniversityGuangzhouChina
| | - Zhongjian Yu
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Xia Yang
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Zhiwu Zhang
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Huili Guo
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
| | - Rui Guo
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development, Department of Biomedical EngineeringJinan UniversityGuangzhouChina
| | - Yanfang Zheng
- Department of Medical OncologyAffiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhouChina
- State Key Laboratory of Respiratory DiseaseGuangzhouChina
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26
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Wang X, Liu D, Luo J, Kong D, Zhang Y. Exploring the Role of Enhancer-Mediated Transcriptional Regulation in Precision Biology. Int J Mol Sci 2023; 24:10843. [PMID: 37446021 PMCID: PMC10342031 DOI: 10.3390/ijms241310843] [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: 05/10/2023] [Revised: 06/18/2023] [Accepted: 06/25/2023] [Indexed: 07/15/2023] Open
Abstract
The emergence of precision biology has been driven by the development of advanced technologies and techniques in high-resolution biological research systems. Enhancer-mediated transcriptional regulation, a complex network of gene expression and regulation in eukaryotes, has attracted significant attention as a promising avenue for investigating the underlying mechanisms of biological processes and diseases. To address biological problems with precision, large amounts of data, functional information, and research on the mechanisms of action of biological molecules is required to address biological problems with precision. Enhancers, including typical enhancers and super enhancers, play a crucial role in gene expression and regulation within this network. The identification and targeting of disease-associated enhancers hold the potential to advance precision medicine. In this review, we present the concepts, progress, importance, and challenges in precision biology, transcription regulation, and enhancers. Furthermore, we propose a model of transcriptional regulation for multi-enhancers and provide examples of their mechanisms in mammalian cells, thereby enhancing our understanding of how enhancers achieve precise regulation of gene expression in life processes. Precision biology holds promise in providing new tools and platforms for discovering insights into gene expression and disease occurrence, ultimately benefiting individuals and society as a whole.
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Affiliation(s)
- Xueyan Wang
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China;
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Livestock and Poultry Multi-Omics of MARA, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; (D.L.); (J.L.); (D.K.)
| | - Danli Liu
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Livestock and Poultry Multi-Omics of MARA, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; (D.L.); (J.L.); (D.K.)
| | - Jing Luo
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Livestock and Poultry Multi-Omics of MARA, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; (D.L.); (J.L.); (D.K.)
| | - Dashuai Kong
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Livestock and Poultry Multi-Omics of MARA, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; (D.L.); (J.L.); (D.K.)
| | - Yubo Zhang
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China;
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Livestock and Poultry Multi-Omics of MARA, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China; (D.L.); (J.L.); (D.K.)
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27
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Mach P, Giorgetti L. Integrative approaches to study enhancer-promoter communication. Curr Opin Genet Dev 2023; 80:102052. [PMID: 37257410 PMCID: PMC10293802 DOI: 10.1016/j.gde.2023.102052] [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: 03/24/2023] [Revised: 04/21/2023] [Accepted: 04/22/2023] [Indexed: 06/02/2023]
Abstract
The spatiotemporal control of gene expression in complex multicellular organisms relies on noncoding regulatory sequences such as enhancers, which activate transcription of target genes often over large genomic distances. Despite the advances in the identification and characterization of enhancers, the principles and mechanisms by which enhancers select and control their target genes remain largely unknown. Here, we review recent interdisciplinary and quantitative approaches based on emerging techniques that aim to address open questions in the field, notably how regulatory information is encoded in the DNA sequence, how this information is transferred from enhancers to promoters, and how these processes are regulated in time.
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Affiliation(s)
- Pia Mach
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland; University of Basel, Basel, Switzerland. https://twitter.com/@MachPia
| | - Luca Giorgetti
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.
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28
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Abril-Garrido J, Dienemann C, Grabbe F, Velychko T, Lidschreiber M, Wang H, Cramer P. Structural basis of transcription reduction by a promoter-proximal +1 nucleosome. Mol Cell 2023:S1097-2765(23)00255-1. [PMID: 37148879 DOI: 10.1016/j.molcel.2023.04.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/16/2023] [Accepted: 04/11/2023] [Indexed: 05/08/2023]
Abstract
At active human genes, the +1 nucleosome is located downstream of the RNA polymerase II (RNA Pol II) pre-initiation complex (PIC). However, at inactive genes, the +1 nucleosome is found further upstream, at a promoter-proximal location. Here, we establish a model system to show that a promoter-proximal +1 nucleosome can reduce RNA synthesis in vivo and in vitro, and we analyze its structural basis. We find that the PIC assembles normally when the edge of the +1 nucleosome is located 18 base pairs (bp) downstream of the transcription start site (TSS). However, when the nucleosome edge is located further upstream, only 10 bp downstream of the TSS, the PIC adopts an inhibited state. The transcription factor IIH (TFIIH) shows a closed conformation and its subunit XPB contacts DNA with only one of its two ATPase lobes, inconsistent with DNA opening. These results provide a mechanism for nucleosome-dependent regulation of transcription initiation.
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Affiliation(s)
- Julio Abril-Garrido
- 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
| | - Frauke Grabbe
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Taras Velychko
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Michael Lidschreiber
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - Haibo Wang
- 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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29
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Welsh SA, Gardini A. Genomic regulation of transcription and RNA processing by the multitasking Integrator complex. Nat Rev Mol Cell Biol 2023; 24:204-220. [PMID: 36180603 PMCID: PMC9974566 DOI: 10.1038/s41580-022-00534-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2022] [Indexed: 11/09/2022]
Abstract
In higher eukaryotes, fine-tuned activation of protein-coding genes and many non-coding RNAs pivots around the regulated activity of RNA polymerase II (Pol II). The Integrator complex is the only Pol II-associated large multiprotein complex that is metazoan specific, and has therefore been understudied for years. Integrator comprises at least 14 subunits, which are grouped into distinct functional modules. The phosphodiesterase activity of the core catalytic module is co-transcriptionally directed against several RNA species, including long non-coding RNAs (lncRNAs), U small nuclear RNAs (U snRNAs), PIWI-interacting RNAs (piRNAs), enhancer RNAs and nascent pre-mRNAs. Processing of non-coding RNAs by Integrator is essential for their biogenesis, and at protein-coding genes, Integrator is a key modulator of Pol II promoter-proximal pausing and transcript elongation. Recent studies have identified an Integrator-specific serine/threonine-protein phosphatase 2A (PP2A) module, which targets Pol II and other components of the basal transcription machinery. In this Review, we discuss how the activity of Integrator regulates transcription, RNA processing, chromatin landscape and DNA repair. We also discuss the diverse roles of Integrator in development and tumorigenesis.
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30
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Gorbea Colón JJ, Palao L, Chen SF, Kim HJ, Snyder L, Chang YW, Tsai KL, Murakami K. Structural basis of a transcription pre-initiation complex on a divergent promoter. Mol Cell 2023; 83:574-588.e11. [PMID: 36731470 PMCID: PMC10162435 DOI: 10.1016/j.molcel.2023.01.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 11/28/2022] [Accepted: 01/06/2023] [Indexed: 02/04/2023]
Abstract
Most eukaryotic promoter regions are divergently transcribed. As the RNA polymerase II pre-initiation complex (PIC) is intrinsically asymmetric and responsible for transcription in a single direction, it is unknown how divergent transcription arises. Here, the Saccharomyces cerevisiae Mediator complexed with a PIC (Med-PIC) was assembled on a divergent promoter and analyzed by cryoelectron microscopy. The structure reveals two distinct Med-PICs forming a dimer through the Mediator tail module, induced by a homodimeric activator protein localized near the dimerization interface. The tail dimer is associated with ∼80-bp upstream DNA, such that two flanking core promoter regions are positioned and oriented in a suitable form for PIC assembly in opposite directions. Also, cryoelectron tomography visualized the progress of the PIC assembly on the two core promoter regions, providing direct evidence for the role of the Med-PIC dimer in divergent transcription.
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Affiliation(s)
- Jose J Gorbea Colón
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Leon Palao
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Shin-Fu Chen
- Department of Biochemistry and Molecular Biology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Hee Jong Kim
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Laura Snyder
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yi-Wei Chang
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Kuang-Lei Tsai
- Department of Biochemistry and Molecular Biology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
| | - Kenji Murakami
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Penn Center for Genome Integrity, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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31
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Wang H, Schilbach S, Ninov M, Urlaub H, Cramer P. Structures of transcription preinitiation complex engaged with the +1 nucleosome. Nat Struct Mol Biol 2023; 30:226-232. [PMID: 36411341 PMCID: PMC9935396 DOI: 10.1038/s41594-022-00865-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 10/07/2022] [Indexed: 11/22/2022]
Abstract
The preinitiation complex (PIC) assembles on promoters of protein-coding genes to position RNA polymerase II (Pol II) for transcription initiation. Previous structural studies revealed the PIC on different promoters, but did not address how the PIC assembles within chromatin. In the yeast Saccharomyces cerevisiae, PIC assembly occurs adjacent to the +1 nucleosome that is located downstream of the core promoter. Here we present cryo-EM structures of the yeast PIC bound to promoter DNA and the +1 nucleosome located at three different positions. The general transcription factor TFIIH engages with the incoming downstream nucleosome and its translocase subunit Ssl2 (XPB in human TFIIH) drives the rotation of the +1 nucleosome leading to partial detachment of nucleosomal DNA and intimate interactions between TFIIH and the nucleosome. The structures provide insights into how transcription initiation can be influenced by the +1 nucleosome and may explain why the transcription start site is often located roughly 60 base pairs upstream of the dyad of the +1 nucleosome in yeast.
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Affiliation(s)
- Haibo Wang
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.,Cancer Institute of the Second Affiliated Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Sandra Schilbach
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Momchil Ninov
- Bioanalytical Mass Spectrometry, 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
| | - Patrick Cramer
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
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32
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When transcription initiation meets chromatin. Nat Struct Mol Biol 2023; 30:131-133. [PMID: 36725911 DOI: 10.1038/s41594-022-00916-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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33
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Lambert É, Puwakdandawa K, Tao YF, Robert F. From structure to molecular condensates: emerging mechanisms for Mediator function. FEBS J 2023; 290:286-309. [PMID: 34698446 DOI: 10.1111/febs.16250] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 10/15/2021] [Accepted: 10/25/2021] [Indexed: 02/05/2023]
Abstract
Mediator is a large modular protein assembly whose function as a coactivator of transcription is conserved in all eukaryotes. The Mediator complex can integrate and relay signals from gene-specific activators bound at enhancers to activate the general transcription machinery located at promoters. It has thus been described as a bridge between these elements during initiation of transcription. Here, we review recent studies on Mediator relating to its structure, gene specificity and general requirement, roles in chromatin architecture as well as novel concepts involving phase separation and transcriptional bursting. We revisit the mechanism of action of Mediator and ultimately put forward models for its mode of action in gene activation.
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Affiliation(s)
- Élie Lambert
- Institut de recherches cliniques de Montréal, Canada
| | | | - Yi Fei Tao
- Institut de recherches cliniques de Montréal, Canada
| | - François Robert
- Institut de recherches cliniques de Montréal, Canada.,Département de Médecine, Faculté de Médecine, Université de Montréal, Canada
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34
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Dunn MJ, Shazib SUA, Simonton E, Slot JC, Anderson MZ. Architectural groups of a subtelomeric gene family evolve along distinct paths in Candida albicans. G3 (BETHESDA, MD.) 2022; 12:jkac283. [PMID: 36269198 PMCID: PMC9713401 DOI: 10.1093/g3journal/jkac283] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 10/09/2022] [Indexed: 12/08/2023]
Abstract
Subtelomeres are dynamic genomic regions shaped by elevated rates of recombination, mutation, and gene birth/death. These processes contribute to formation of lineage-specific gene family expansions that commonly occupy subtelomeres across eukaryotes. Investigating the evolution of subtelomeric gene families is complicated by the presence of repetitive DNA and high sequence similarity among gene family members that prevents accurate assembly from whole genome sequences. Here, we investigated the evolution of the telomere-associated (TLO) gene family in Candida albicans using 189 complete coding sequences retrieved from 23 genetically diverse strains across the species. Tlo genes conformed to the 3 major architectural groups (α/β/γ) previously defined in the genome reference strain but significantly differed in the degree of within-group diversity. One group, Tloβ, was always found at the same chromosome arm with strong sequence similarity among all strains. In contrast, diverse Tloα sequences have proliferated among chromosome arms. Tloγ genes formed 7 primary clades that included each of the previously identified Tloγ genes from the genome reference strain with 3 Tloγ genes always found on the same chromosome arm among strains. Architectural groups displayed regions of high conservation that resolved newly identified functional motifs, providing insight into potential regulatory mechanisms that distinguish groups. Thus, by resolving intraspecies subtelomeric gene variation, it is possible to identify previously unknown gene family complexity that may underpin adaptive functional variation.
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Affiliation(s)
- Matthew J Dunn
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
| | - Shahed U A Shazib
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
| | - Emily Simonton
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
| | - Jason C Slot
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, USA
| | - Matthew Z Anderson
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210, USA
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35
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Li ZM, Liu G, Gao Y, Zhao MG. Targeting CDK7 in oncology: The avenue forward. Pharmacol Ther 2022; 240:108229. [PMID: 35700828 DOI: 10.1016/j.pharmthera.2022.108229] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 06/02/2022] [Accepted: 06/07/2022] [Indexed: 12/14/2022]
Abstract
Cyclin-dependent kinase (CDK) 7 is best characterized for the ability to regulate biological processes, including the cell cycle and gene transcription. Abnormal CDK7 activity is observed in various tumours and represents a driving force for tumourigenesis. Therefore, CDK7 may be an appealing target for cancer treatment. Whereas, the enthusiasm for CDK7-targeted therapeutic strategy is mitigated due to the widely possessed belief that this protein is essential for normal cells. Indeed, the fact confronts the consensus. This is the first review to introduce the role of CDK7 in pan-cancers via a combined analysis of comprehensive gene information and (pre)clinical research results. We also discuss the recent advances in protein structure and summarize the understanding of mechanisms underlying CDK7 function. These endeavours highlight the pivotal roles of CDK7 in tumours and may contribute to the development of effective CDK7 inhibitors within the strategy of structure-based drug discovery for cancer therapy.
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Affiliation(s)
- Zhi-Mei Li
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an 710072, Shaanxi, PR China
| | - Guan Liu
- Department of General Surgery, Tangdu Hospital, Fourth Military Medical University, Xinsi Road 1, Xi'an 710038, Shaanxi, PR China
| | - Ya Gao
- State Key Laboratory of Esophageal Cancer Prevention and Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Institute of Drug Discovery and Development, School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou 450001, Henan, PR China.
| | - Ming-Gao Zhao
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an 710072, Shaanxi, PR China; Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xinsi Road 1, Xi'an 710038, Shaanxi, PR China.
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Bajracharya A, Xi J, Grace KF, Bayer EE, Grant CA, Clutton CH, Baerson SR, Agarwal AK, Qiu Y. PHYTOCHROME-INTERACTING FACTOR 4/HEMERA-mediated thermosensory growth requires the Mediator subunit MED14. PLANT PHYSIOLOGY 2022; 190:2706-2721. [PMID: 36063057 PMCID: PMC9706435 DOI: 10.1093/plphys/kiac412] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 08/12/2022] [Indexed: 05/19/2023]
Abstract
While moderately elevated ambient temperatures do not trigger stress responses in plants, they do substantially stimulate the growth of specific organs through a process known as thermomorphogenesis. The basic helix-loop-helix transcription factor PHYTOCHROME-INTERACTING FACTOR 4 (PIF4) plays a central role in regulating thermomorphogenetic hypocotyl elongation in various plant species, including Arabidopsis (Arabidopsis thaliana). Although it is well known that PIF4 and its co-activator HEMERA (HMR) promote plant thermosensory growth by activating genes involved in the biosynthesis and signaling of the phytohormone auxin, the detailed molecular mechanism of such transcriptional activation is not clear. In this report, we investigated the role of the Mediator complex in the PIF4/HMR-mediated thermoresponsive gene expression. Through the characterization of various mutants of the Mediator complex, a tail subunit named MED14 was identified as an essential factor for thermomorphogenetic hypocotyl growth. MED14 was required for the thermal induction of PIF4 target genes but had a marginal effect on the levels of PIF4 and HMR. Further transcriptomic analyses confirmed that the expression of numerous PIF4/HMR-dependent, auxin-related genes required MED14 at warm temperatures. Moreover, PIF4 and HMR physically interacted with MED14 and both were indispensable for the association of MED14 with the promoters of these thermoresponsive genes. While PIF4 did not regulate MED14 levels, HMR was required for the transcript abundance of MED14. Taken together, these results unveil an important thermomorphogenetic mechanism, in which PIF4 and HMR recruit the Mediator complex to activate auxin-related growth-promoting genes when plants sense moderate increases in ambient temperature.
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Affiliation(s)
| | - Jing Xi
- Natural Products Utilization Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Oxford, Mississippi, USA
| | - Karlie F Grace
- Department of Biology, University of Mississippi, Oxford, Mississippi 38677, USA
| | - Eden E Bayer
- Department of Biology, University of Mississippi, Oxford, Mississippi 38677, USA
| | - Chloe A Grant
- Department of Biology, University of Mississippi, Oxford, Mississippi 38677, USA
| | - Caroline H Clutton
- Department of Biology, University of Mississippi, Oxford, Mississippi 38677, USA
| | - Scott R Baerson
- Natural Products Utilization Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Oxford, Mississippi, USA
| | - Ameeta K Agarwal
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
- Division of Pharmacology, Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
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Warfield L, Donczew R, Mahendrawada L, Hahn S. Yeast Mediator facilitates transcription initiation at most promoters via a Tail-independent mechanism. Mol Cell 2022; 82:4033-4048.e7. [PMID: 36208626 PMCID: PMC9637718 DOI: 10.1016/j.molcel.2022.09.016] [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: 12/14/2021] [Revised: 05/12/2022] [Accepted: 09/13/2022] [Indexed: 11/06/2022]
Abstract
Mediator (MED) is a conserved factor with important roles in basal and activated transcription. Here, we investigate the genome-wide roles of yeast MED by rapid depletion of its activator-binding domain (Tail) and monitoring changes in nascent transcription. Rapid Tail depletion surprisingly reduces transcription from only a small subset of genes. At most of these Tail-dependent genes, in unperturbed conditions, MED is detected at both the UASs and promoters. In contrast, at most Tail-independent genes, we find MED primarily at promoters but not at the UASs. These results suggest that MED Tail and activator-mediated MED recruitment regulates only a small subset of genes. Furthermore, we define three classes of genes that differ in PIC assembly pathways and the requirements for MED Tail, SAGA, TFIID, and BET factors Bdf1/2. Our combined results have broad implications for the roles of MED, other coactivators, and mechanisms of transcriptional regulation at different gene classes.
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Affiliation(s)
- Linda Warfield
- Fred Hutchinson Cancer Center, 1100 Fairview Ave N, Mailstop A1-162, Seattle, WA 98109, USA
| | - Rafal Donczew
- Fred Hutchinson Cancer Center, 1100 Fairview Ave N, Mailstop A1-162, Seattle, WA 98109, USA
| | - Lakshmi Mahendrawada
- Fred Hutchinson Cancer Center, 1100 Fairview Ave N, Mailstop A1-162, Seattle, WA 98109, USA
| | - Steven Hahn
- Fred Hutchinson Cancer Center, 1100 Fairview Ave N, Mailstop A1-162, Seattle, WA 98109, USA.
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Richter WF, Nayak S, Iwasa J, Taatjes DJ. The Mediator complex as a master regulator of transcription by RNA polymerase II. Nat Rev Mol Cell Biol 2022; 23:732-749. [PMID: 35725906 PMCID: PMC9207880 DOI: 10.1038/s41580-022-00498-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2022] [Indexed: 02/08/2023]
Abstract
The Mediator complex, which in humans is 1.4 MDa in size and includes 26 subunits, controls many aspects of RNA polymerase II (Pol II) function. Apart from its size, a defining feature of Mediator is its intrinsic disorder and conformational flexibility, which contributes to its ability to undergo phase separation and to interact with a myriad of regulatory factors. In this Review, we discuss Mediator structure and function, with emphasis on recent cryogenic electron microscopy data of the 4.0-MDa transcription preinitiation complex. We further discuss how Mediator and sequence-specific DNA-binding transcription factors enable enhancer-dependent regulation of Pol II function at distal gene promoters, through the formation of molecular condensates (or transcription hubs) and chromatin loops. Mediator regulation of Pol II reinitiation is also discussed, in the context of transcription bursting. We propose a working model for Mediator function that combines experimental results and theoretical considerations related to enhancer-promoter interactions, which reconciles contradictory data regarding whether enhancer-promoter communication is direct or indirect. We conclude with a discussion of Mediator's potential as a therapeutic target and of future research directions.
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Affiliation(s)
- William F Richter
- Department of Biochemistry, University of Colorado, Boulder, CO, USA
| | - Shraddha Nayak
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Janet Iwasa
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Dylan J Taatjes
- Department of Biochemistry, University of Colorado, Boulder, CO, USA.
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Chen X, Wang X, Liu W, Ren Y, Qu X, Li J, Yin X, Xu Y. Structures of +1 nucleosome-bound PIC-Mediator complex. Science 2022; 378:62-68. [PMID: 36201575 DOI: 10.1126/science.abn8131] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
RNA polymerase II-mediated eukaryotic transcription starts with the assembly of the preinitiation complex (PIC) on core promoters. The +1 nucleosome is well positioned about 40 base pairs downstream of the transcription start site (TSS) and is commonly known as a barrier of transcription. The +1 nucleosome-bound PIC-Mediator structures show that PIC-Mediator prefers binding to T40N nucleosome located 40 base pairs downstream of TSS and contacts T50N but not the T70N nucleosome. The nucleosome facilitates the organization of PIC-Mediator on the promoter by binding TFIIH subunit p52 and Mediator subunits MED19 and MED26 and may contribute to transcription initiation. PIC-Mediator exhibits multiple nucleosome-binding patterns, supporting a structural role of the +1 nucleosome in the coordination of PIC-Mediator assembly. Our study reveals the molecular mechanism of PIC-Mediator organization on chromatin and underscores the significance of the +1 nucleosome in regulating transcription initiation.
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Affiliation(s)
- Xizi Chen
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Xinxin Wang
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Weida Liu
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Yulei Ren
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Xuechun Qu
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Jiabei Li
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, and Shanghai Key Laboratory of Medical Epigenetics, Shanghai Medical College of Fudan University, Shanghai 200032, China
| | - Xiaotong Yin
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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.,Human Phenome Institute, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200433, China
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Calì E, Lin SJ, Rocca C, Sahin Y, Al Shamsi A, El Chehadeh S, Chaabouni M, Mankad K, Galanaki E, Efthymiou S, Sudhakar S, Athanasiou-Fragkouli A, Çelik T, Narlı N, Bianca S, Murphy D, De Carvalho Moreira FM, Andrea Accogli, Petree C, Huang K, Monastiri K, Edizadeh M, Nardello R, Ognibene M, De Marco P, Ruggieri M, Zara F, Striano P, Şahin Y, Al-Gazali L, Abi Warde MT, Gerard B, Zifarelli G, Beetz C, Fortuna S, Soler M, Valente EM, Varshney G, Maroofian R, Salpietro V, Houlden H. A homozygous MED11 C-terminal variant causes a lethal neurodegenerative disease. Genet Med 2022; 24:2194-2203. [PMID: 36001086 PMCID: PMC10519206 DOI: 10.1016/j.gim.2022.07.013] [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: 04/05/2022] [Revised: 07/07/2022] [Accepted: 07/11/2022] [Indexed: 02/05/2023] Open
Abstract
PURPOSE The mediator (MED) multisubunit-complex modulates the activity of the transcriptional machinery, and genetic defects in different MED subunits (17, 20, 27) have been implicated in neurologic diseases. In this study, we identified a recurrent homozygous variant in MED11 (c.325C>T; p.Arg109Ter) in 7 affected individuals from 5 unrelated families. METHODS To investigate the genetic cause of the disease, exome or genome sequencing were performed in 5 unrelated families identified via different research networks and Matchmaker Exchange. Deep clinical and brain imaging evaluations were performed by clinical pediatric neurologists and neuroradiologists. The functional effect of the candidate variant on both MED11 RNA and protein was assessed using reverse transcriptase polymerase chain reaction and western blotting using fibroblast cell lines derived from 1 affected individual and controls and through computational approaches. Knockouts in zebrafish were generated using clustered regularly interspaced short palindromic repeats/Cas9. RESULTS The disease was characterized by microcephaly, profound neurodevelopmental impairment, exaggerated startle response, myoclonic seizures, progressive widespread neurodegeneration, and premature death. Functional studies on patient-derived fibroblasts did not show a loss of protein function but rather disruption of the C-terminal of MED11, likely impairing binding to other MED subunits. A zebrafish knockout model recapitulates key clinical phenotypes. CONCLUSION Loss of the C-terminal of MED subunit 11 may affect its binding efficiency to other MED subunits, thus implicating the MED-complex stability in brain development and neurodegeneration.
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Affiliation(s)
- Elisa Calì
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Sheng-Jia Lin
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | - Clarissa Rocca
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Yavuz Sahin
- Department of Medical Genetics, Genoks Genetic Laboratory, Ankara, Turkey
| | | | - Salima El Chehadeh
- Service de Génétique Médicale, Institut de Génétique Médicale d'Alsace (IGMA), Centre de Référence des Déficiences Intellectuelles de Causes Rares, Centre de Recherche en Biomédecine de Strasbourg (CRBS), Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | | | - Kshitij Mankad
- Department of Radiology, Great Ormond Street Hospital for Children, London, United Kingdom
| | - Evangelia Galanaki
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Stephanie Efthymiou
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Sniya Sudhakar
- Department of Radiology, Great Ormond Street Hospital for Children, London, United Kingdom
| | | | - Tamer Çelik
- Department of Pediatric Neurology, Private Practice, Adana, Turkey
| | - Nejat Narlı
- Division of Neonatology, Department of Pediatrics, Medical School, Cukurova University, Adana, Turkey
| | - Sebastiano Bianca
- Medical Genetics, Referral Centre for Rare Genetic Diseases, ARNAS Garibaldi, Catania, Italy
| | - David Murphy
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
| | | | - Andrea Accogli
- Division of Medical Genetics, Department of Specialized Medicine, Montreal Children's Hospital, McGill University Health Centre (MUHC), Montreal, Quebec, Canada; Department of Human Genetics, McGill University, Montreal, Quebec, Canada
| | - Cassidy Petree
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | - Kevin Huang
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | - Kamel Monastiri
- Department of Neonatology, Fattouma Bourguiba Hospital, Monastir, Tunisia
| | - Masoud Edizadeh
- Department of Medical Genetics, Genoks Genetic Laboratory, Ankara, Turkey
| | - Rosaria Nardello
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities "G. D'Alessandro," University of Palermo, Palermo, Italy
| | - Marzia Ognibene
- Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Patrizia De Marco
- Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Martino Ruggieri
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, AOU "Policlinico," University of Catania, Catania, Italy
| | - Federico Zara
- Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, Genoa, Italy; Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Pediatric Neurology and Muscular Diseases Unit, IRCCS "Istituto Giannina Gaslini," Genova, Italy
| | - Yavuz Şahin
- Department of Medical Genetics, Biruni University, İstanbul, Turkey
| | - Lihadh Al-Gazali
- Department of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | | | - Benedicte Gerard
- Laboratoires de Diagnostic Génétique, Unité de Génétique Moléculaire, Nouvel Hôpital Civil, Strasbourg Cedex, France
| | | | | | - Sara Fortuna
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste, Italy
| | - Miguel Soler
- CONCEPT Lab, Italian Institute of Technology (IIT), Genova, Italy
| | - Enza Maria Valente
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Neurogenetics Research Center, IRCCS Mondino Foundation, Pavia, Italy
| | - Gaurav Varshney
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK
| | - Reza Maroofian
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Vincenzo Salpietro
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom; Department of Pediatrics, University of L'Aquila, L'Aquila, Italy.
| | - Henry Houlden
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
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Tanemoto F, Nangaku M, Mimura I. Epigenetic memory contributing to the pathogenesis of AKI-to-CKD transition. Front Mol Biosci 2022; 9:1003227. [PMID: 36213117 PMCID: PMC9532834 DOI: 10.3389/fmolb.2022.1003227] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 08/24/2022] [Indexed: 11/18/2022] Open
Abstract
Epigenetic memory, which refers to the ability of cells to retain and transmit epigenetic marks to their daughter cells, maintains unique gene expression patterns. Establishing programmed epigenetic memory at each stage of development is required for cell differentiation. Moreover, accumulating evidence shows that epigenetic memory acquired in response to environmental stimuli may be associated with diverse diseases. In the field of kidney diseases, the “memory” of acute kidney injury (AKI) leads to progression to chronic kidney disease (CKD); epidemiological studies show that patients who recover from AKI are at high risk of developing CKD. The underlying pathological processes include nephron loss, maladaptive epithelial repair, inflammation, and endothelial injury with vascular rarefaction. Further, epigenetic alterations may contribute as well to the pathophysiology of this AKI-to-CKD transition. Epigenetic changes induced by AKI, which can be recorded in cells, exert long-term effects as epigenetic memory. Considering the latest findings on the molecular basis of epigenetic memory and the pathophysiology of AKI-to-CKD transition, we propose here that epigenetic memory contributing to AKI-to-CKD transition can be classified according to the presence or absence of persistent changes in the associated regulation of gene expression, which we designate “driving” memory and “priming” memory, respectively. “Driving” memory, which persistently alters the regulation of gene expression, may contribute to disease progression by activating fibrogenic genes or inhibiting renoprotective genes. This process may be involved in generating the proinflammatory and profibrotic phenotypes of maladaptively repaired tubular cells after kidney injury. “Priming” memory is stored in seemingly successfully repaired tubular cells in the absence of detectable persistent phenotypic changes, which may enhance a subsequent transcriptional response to the second stimulus. This type of memory may contribute to AKI-to-CKD transition through the cumulative effects of enhanced expression of profibrotic genes required for wound repair after recurrent AKI. Further understanding of epigenetic memory will identify therapeutic targets of future epigenetic intervention to prevent AKI-to-CKD transition.
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42
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Chen X, Xu Y. Structural insights into assembly of transcription preinitiation complex. Curr Opin Struct Biol 2022; 75:102404. [PMID: 35700575 DOI: 10.1016/j.sbi.2022.102404] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 05/05/2022] [Accepted: 05/12/2022] [Indexed: 01/24/2023]
Abstract
RNA polymerase II (Pol II)-mediated transcription in eukaryotic cells starts with assembly of preinitiation complex (PIC) on core promoter, a DNA sequence of ∼100 base pairs. The transcription PIC consists of Pol II and general transcription factors TFIID, TFIIA, TFIIB, TFIIF, TFIIE, and TFIIH. Previous structural studies focused on PIC assembled on TATA box promoters with TFIID replaced by its subunit, TATA box-binding protein (TBP). However, the megadalton TFIID complex is essential for promoter recognition, TBP loading onto promoter, and PIC assembly for almost all Pol II-mediated transcription, especially on the TATA-less promoters, which account for ∼85% of core promoters of human coding genes. The functions of TFIID could not be replaced by TBP. The recent breakthrough in structure determination of TFIID-based PIC complexes in different assembly stages revealed mechanistic insights into PIC assembly on TATA box and TATA-less promotes and provided a framework for further investigation of transcription initiation.
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Affiliation(s)
- Xizi Chen
- Fudan University Shanghai Cancer Center, Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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, Department of Biochemistry and Biophysics, School of Life Sciences, Shanghai Key Laboratory of Radiation Oncology, 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; Human Phenome Institute, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200433, China.
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Differential cofactor dependencies define distinct types of human enhancers. Nature 2022; 606:406-413. [PMID: 35650434 PMCID: PMC7613064 DOI: 10.1038/s41586-022-04779-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 04/20/2022] [Indexed: 12/24/2022]
Abstract
All multicellular organisms rely on differential gene transcription regulated by genomic enhancers, which function through cofactors that are recruited by transcription factors1,2. Emerging evidence suggests that not all cofactors are required at all enhancers3-5, yet whether these observations reflect more general principles or distinct types of enhancers remained unknown. Here we categorized human enhancers by their cofactor dependencies and show that these categories provide a framework to understand the sequence and chromatin diversity of enhancers and their roles in different gene-regulatory programmes. We quantified enhancer activities along the entire human genome using STARR-seq6 in HCT116 cells, following the rapid degradation of eight cofactors. This analysis identified different types of enhancers with distinct cofactor requirements, sequences and chromatin properties. Some enhancers were insensitive to the depletion of the core Mediator subunit MED14 or the bromodomain protein BRD4 and regulated distinct transcriptional programmes. In particular, canonical Mediator7 seemed dispensable for P53-responsive enhancers, and MED14-depleted cells induced endogenous P53 target genes. Similarly, BRD4 was not required for the transcription of genes that bear CCAAT boxes and a TATA box (including histone genes and LTR12 retrotransposons) or for the induction of heat-shock genes. This categorization of enhancers through cofactor dependencies reveals distinct enhancer types that can bypass broadly utilized cofactors, which illustrates how alternative ways to activate transcription separate gene expression programmes and provide a conceptual framework to understand enhancer function and regulatory specificity.
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Eigenhuis KN, Somsen HB, van den Berg DLC. Transcription Pause and Escape in Neurodevelopmental Disorders. Front Neurosci 2022; 16:846272. [PMID: 35615272 PMCID: PMC9125161 DOI: 10.3389/fnins.2022.846272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 04/11/2022] [Indexed: 11/17/2022] Open
Abstract
Transcription pause-release is an important, highly regulated step in the control of gene expression. Modulated by various factors, it enables signal integration and fine-tuning of transcriptional responses. Mutations in regulators of pause-release have been identified in a range of neurodevelopmental disorders that have several common features affecting multiple organ systems. This review summarizes current knowledge on this novel subclass of disorders, including an overview of clinical features, mechanistic details, and insight into the relevant neurodevelopmental processes.
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45
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Structural insights into nuclear transcription by eukaryotic DNA-dependent RNA polymerases. Nat Rev Mol Cell Biol 2022; 23:603-622. [PMID: 35505252 DOI: 10.1038/s41580-022-00476-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2022] [Indexed: 02/07/2023]
Abstract
The eukaryotic transcription apparatus synthesizes a staggering diversity of RNA molecules. The labour of nuclear gene transcription is, therefore, divided among multiple DNA-dependent RNA polymerases. RNA polymerase I (Pol I) transcribes ribosomal RNA, Pol II synthesizes messenger RNAs and various non-coding RNAs (including long non-coding RNAs, microRNAs and small nuclear RNAs) and Pol III produces transfer RNAs and other short RNA molecules. Pol I, Pol II and Pol III are large, multisubunit protein complexes that associate with a multitude of additional factors to synthesize transcripts that largely differ in size, structure and abundance. The three transcription machineries share common characteristics, but differ widely in various aspects, such as numbers of RNA polymerase subunits, regulatory elements and accessory factors, which allows them to specialize in transcribing their specific RNAs. Common to the three RNA polymerases is that the transcription process consists of three major steps: transcription initiation, transcript elongation and transcription termination. In this Review, we outline the common principles and differences between the Pol I, Pol II and Pol III transcription machineries and discuss key structural and functional insights obtained into the three stages of their transcription processes.
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RPAP2 regulates a transcription initiation checkpoint by inhibiting assembly of pre-initiation complex. Cell Rep 2022; 39:110732. [PMID: 35476980 DOI: 10.1016/j.celrep.2022.110732] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 12/31/2021] [Accepted: 04/02/2022] [Indexed: 11/21/2022] Open
Abstract
RNA polymerase II (Pol II)-mediated transcription in metazoans requires precise regulation. RNA Pol II-associated protein 2 (RPAP2) was previously identified to transport Pol II from cytoplasm to nucleus and dephosphorylates Pol II C-terminal domain (CTD). Here, we show that RPAP2 binds hypo-/hyper-phosphorylated Pol II with undetectable phosphatase activity. The structure of RPAP2-Pol II shows mutually exclusive assembly of RPAP2-Pol II and pre-initiation complex (PIC) due to three steric clashes. RPAP2 prevents and disrupts Pol II-TFIIF interaction and impairs in vitro transcription initiation, suggesting a function in inhibiting PIC assembly. Loss of RPAP2 in cells leads to global accumulation of TFIIF and Pol II at promoters, indicating a critical role of RPAP2 in inhibiting PIC assembly independent of its putative phosphatase activity. Our study indicates that RPAP2 functions as a gatekeeper to inhibit PIC assembly and transcription initiation and suggests a transcription checkpoint.
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Farnung L, Vos SM. Assembly of RNA polymerase II transcription initiation complexes. Curr Opin Struct Biol 2022; 73:102335. [DOI: 10.1016/j.sbi.2022.102335] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 12/28/2021] [Accepted: 01/04/2022] [Indexed: 11/03/2022]
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Ahmad K, Henikoff S, Ramachandran S. Managing the Steady State Chromatin Landscape by Nucleosome Dynamics. Annu Rev Biochem 2022; 91:183-195. [PMID: 35303789 DOI: 10.1146/annurev-biochem-032620-104508] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Gene regulation arises out of dynamic competition between nucleosomes, transcription factors, and other chromatin proteins for the opportunity to bind genomic DNA. The timescales of nucleosome assembly and binding of factors to DNA determine the outcomes of this competition at any given locus. Here, we review how these properties of chromatin proteins and the interplay between the dynamics of different factors are critical for gene regulation. We discuss how molecular structures of large chromatin-associated complexes, kinetic measurements, and high resolution mapping of protein-DNA complexes in vivo set the boundary conditions for chromatin dynamics, leading to models of how the steady state behaviors of regulatory elements arise. Expected final online publication date for the Annual Review of Biochemistry, Volume 91 is June 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Kami Ahmad
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA;
| | - Steven Henikoff
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA; .,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Srinivas Ramachandran
- Department of Biochemistry and Molecular Genetics and RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, Colorado, USA
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The Mediator kinase module: an interface between cell signaling and transcription. Trends Biochem Sci 2022; 47:314-327. [DOI: 10.1016/j.tibs.2022.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 01/11/2022] [Accepted: 01/17/2022] [Indexed: 12/14/2022]
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