1
|
Li J, Guo D, Bai J, Wang H, Wang C, Wang Y, Guo X, Xu B, Liu Z. Isolation of the AccCDK8 gene of Apis cerana cerana and its functional analysis under pesticide and heavy metal stress. Biochimie 2024; 218:57-68. [PMID: 37704078 DOI: 10.1016/j.biochi.2023.09.012] [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: 04/14/2023] [Revised: 07/25/2023] [Accepted: 09/10/2023] [Indexed: 09/15/2023]
Abstract
Environmental pollution has gained negative attention in recent years. The pesticides and heavy metals are top list of environmental toxicants directly endangering the survival and development of Apis cerana cerana. Cyclin-dependent kinases (CDKs) are heteromeric serine/threonine kinases that participate in cell cycle regulation and have a vital role in pesticide and heavy metal stress in Apis cerana cerana. In this experiment, we filtered out CDK8 gene from Apis cerana cerana (AccCDK8) and investigated its functions of pesticide and heavy metals resistance. Sequence analysis indicated that AccCDK8 is highly homologous to multiple CDK8s and contains a highly conserved CDK active site sequence. Phylogenetic analysis showed that AmCDK8 and AccCDK8 were closely related evolutionarily in Apis mellifera. Transcriptome analysis revealed that AccCDK8 expression was differentially affected after exposure to pesticide and heavy metal stresses. This indicates that AccCDK8 has a significant role in the resistance of Apis cerana cerana to pesticide and heavy metal stresses. It has implications for studying the function of CDK in other insects in response to stress.
Collapse
Affiliation(s)
- Jing Li
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China
| | - Dezheng Guo
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China
| | - Jinhao Bai
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China
| | - Hongfang Wang
- College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China
| | - Chen Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China
| | - Ying Wang
- College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China
| | - Xingqi Guo
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China
| | - Baohua Xu
- College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China
| | - Zhenguo Liu
- College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China.
| |
Collapse
|
2
|
Alberghina L. The Warburg Effect Explained: Integration of Enhanced Glycolysis with Heterogeneous Mitochondria to Promote Cancer Cell Proliferation. Int J Mol Sci 2023; 24:15787. [PMID: 37958775 PMCID: PMC10648413 DOI: 10.3390/ijms242115787] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/19/2023] [Accepted: 10/25/2023] [Indexed: 11/15/2023] Open
Abstract
The Warburg effect is the long-standing riddle of cancer biology. How does aerobic glycolysis, inefficient in producing ATP, confer a growth advantage to cancer cells? A new evaluation of a large set of literature findings covering the Warburg effect and its yeast counterpart, the Crabtree effect, led to an innovative working hypothesis presented here. It holds that enhanced glycolysis partially inactivates oxidative phosphorylation to induce functional rewiring of a set of TCA cycle enzymes to generate new non-canonical metabolic pathways that sustain faster growth rates. The hypothesis has been structured by constructing two metabolic maps, one for cancer metabolism and the other for the yeast Crabtree effect. New lines of investigation, suggested by these maps, are discussed as instrumental in leading toward a better understanding of cancer biology in order to allow the development of more efficient metabolism-targeted anticancer drugs.
Collapse
Affiliation(s)
- Lilia Alberghina
- Centre of Systems Biology, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
| |
Collapse
|
3
|
Reyes-Castro RA, Chen SY, Seemann J, Kundu ST, Gibbons DL, Arur S. Phosphorylated nuclear DICER1 promotes open chromatin state and lineage plasticity of AT2 tumor cells in lung adenocarcinomas. SCIENCE ADVANCES 2023; 9:eadf6210. [PMID: 37494452 PMCID: PMC10371025 DOI: 10.1126/sciadv.adf6210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 06/22/2023] [Indexed: 07/28/2023]
Abstract
KRAS/ERK pathway phosphorylates DICER1, causing its nuclear translocation, and phosphomimetic Dicer1 contributes to tumorigenesis in mice. Mechanisms through which phospho-DICER1 regulates tumor progression remain undefined. While DICER1 canonically regulates microRNAs (miRNA) and epithelial-to-mesenchymal transition (EMT), we found that phosphorylated nuclear DICER1 (phospho-nuclear DICER1) promotes late-stage tumor progression in mice with oncogenic Kras, independent of miRNAs and EMT. Instead, we observe that the murine AT2 tumor cells exhibit altered chromatin compaction, and cells from disorganized advanced tumors, but not localized tumors, express gastric genes. Collectively, this results in subpopulations of tumor cells transitioning from a restricted alveolar to a broader endodermal lineage state. In human LUADs, we observed expression of phospho-nuclear DICER1 in advanced tumors together with the expression of gastric genes. We define a multimeric chromatin-DICER1 complex composed of the Mediator complex subunit 12, CBX1, MACROH2A.1, and transcriptional regulators supporting the model that phospho-nuclear DICER1 leads to lineage reprogramming of AT2 tumor cells to mediate lung cancer progression.
Collapse
Affiliation(s)
- Raisa A. Reyes-Castro
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- School of Medicine, University of Puerto Rico, San Juan, Puerto Rico
- Genetics and Epigenetics Graduate Program, The University of Texas MD Anderson Cancer Center and UTHealth Houston Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Shin-Yu Chen
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jacob Seemann
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Samrat T. Kundu
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Don L. Gibbons
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Swathi Arur
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Genetics and Epigenetics Graduate Program, The University of Texas MD Anderson Cancer Center and UTHealth Houston Graduate School of Biomedical Sciences, Houston, TX, USA
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Song Z, Xiaoli AM, Li Y, Siqin G, Wu T, Strich R, Pessin JE, Yang F. The conserved Mediator subunit cyclin C (CCNC) is required for brown adipocyte development and lipid accumulation. Mol Metab 2022; 64:101548. [PMID: 35863637 PMCID: PMC9386464 DOI: 10.1016/j.molmet.2022.101548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 07/05/2022] [Accepted: 07/11/2022] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVE Cyclin C (CCNC) is the most conserved subunit of the Mediator complex, which is an important transcription cofactor. Recently, we have found that CCNC facilitates brown adipogenesis in vitro by activating C/EBPα-dependent transcription. However, the role of CCNC in brown adipose tissue (BAT) in vivo remains unclear. METHODS We generated conditional knock-out mice by crossing Ccncflox/flox mice with Myf5Cre, Ucp1Cre or AdipoqCre transgenic mice to investigate the role of CCNC in BAT development and function. We applied glucose and insulin tolerance test, cold exposure and indirect calorimetry to capture the physiological phenotypes and used immunostaining, immunoblotting, qRT-PCR, RNA-seq and cell culture to elucidate the underlying mechanisms. RESULTS Here, we show that deletion of CCNC in Myf5+ progenitor cells caused BAT paucity, despite the fact that there was significant neonatal lethality. Mechanistically different from in vitro, CCNC deficiency impaired the proliferation of embryonic brown fat progenitor cells without affecting brown adipogenesis or cell death. Interestingly, CCNC deficiency robustly reduced age-dependent lipid accumulation in differentiated brown adipocytes in all three mouse models. Mechanistically, CCNC in brown adipocytes is required for lipogenic gene expression through the activation of the C/EBPα/GLUT4/ChREBP axis. Consistent with the importance of de novo lipogenesis under carbohydrate-rich diets, high-fat diet (HFD) feeding abolished CCNC deficiency -caused defects of lipid accumulation in BAT. Although insulin sensitivity and response to acute cold exposure were not affected, CCNC deficiency in Ucp1+ cells enhanced the browning of white adipose tissue (beiging) upon prolonged cold exposure. CONCLUSIONS Together, these data indicate an important role of CCNC-Mediator in the regulation of BAT development and lipid accumulation in brown adipocytes.
Collapse
Affiliation(s)
- Ziyi Song
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Animal Science and Technology, Guangxi University, Nanning, 530004, China; Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Norman Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Alus M Xiaoli
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Norman Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
| | - Youlei Li
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Norman Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Gerile Siqin
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Norman Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Tian Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Animal Science and Technology, Guangxi University, Nanning, 530004, China
| | - Randy Strich
- Department of Molecular Biology, Rowan University School of Osteopathic Medicine, Stratford, NJ, 08055, USA
| | - Jeffrey E Pessin
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Norman Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Fajun Yang
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Norman Fleischer Institute for Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
| |
Collapse
|
6
|
Chen J, Yang S, Fan B, Zhu C, Chen Z. The Mediator Complex: A Central Coordinator of Plant Adaptive Responses to Environmental Stresses. Int J Mol Sci 2022; 23:ijms23116170. [PMID: 35682844 PMCID: PMC9181133 DOI: 10.3390/ijms23116170] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/22/2022] [Accepted: 05/28/2022] [Indexed: 01/25/2023] Open
Abstract
As sessile organisms, plants are constantly exposed to a variety of environmental stresses and have evolved adaptive mechanisms, including transcriptional reprogramming, in order to survive or acclimate under adverse conditions. Over the past several decades, a large number of gene-specific transcription factors have been identified in the transcriptional regulation of plant adaptive responses. The Mediator complex plays a key role in transducing signals from gene-specific transcription factors to the transcription machinery to activate or repress target gene expression. Since its first purification about 15 years ago, plant Mediator complex has been extensively analyzed for its composition and biological functions. Mutants of many plant Mediator subunits are not lethal but are compromised in growth, development and response to biotic and abiotic stress, underscoring a particularly important role in plant adaptive responses. Plant Mediator subunits also interact with partners other than transcription factors and components of the transcription machinery, indicating the complexity of the regulation of gene expression by plant Mediator complex. Here, we present a comprehensive discussion of recent analyses of the structure and function of plant Mediator complex, with a particular focus on its roles in plant adaptive responses to a wide spectrum of environmental stresses and associated biological processes.
Collapse
Affiliation(s)
- Jialuo Chen
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (J.C.); (S.Y.)
| | - Su Yang
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (J.C.); (S.Y.)
| | - Baofang Fan
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA;
| | - Cheng Zhu
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (J.C.); (S.Y.)
- Correspondence: (C.Z.); (Z.C.); Tel.: +86-571-8683-6090 (C.Z.); +1-765-494-4657 (Z.C.)
| | - Zhixiang Chen
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (J.C.); (S.Y.)
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA;
- Correspondence: (C.Z.); (Z.C.); Tel.: +86-571-8683-6090 (C.Z.); +1-765-494-4657 (Z.C.)
| |
Collapse
|
7
|
Role of Peroxisome Proliferator-Activated Receptors (PPARs) in Energy Homeostasis of Dairy Animals: Exploiting Their Modulation through Nutrigenomic Interventions. Int J Mol Sci 2021; 22:ijms222212463. [PMID: 34830341 PMCID: PMC8619600 DOI: 10.3390/ijms222212463] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/31/2021] [Accepted: 11/16/2021] [Indexed: 12/22/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) are the nuclear receptors that could mediate the nutrient-dependent transcriptional activation and regulate metabolic networks through energy homeostasis. However, these receptors cannot work properly under metabolic stress. PPARs and their subtypes can be modulated by nutrigenomic interventions, particularly under stress conditions to restore cellular homeostasis. Many nutrients such as polyunsaturated fatty acids, vitamins, dietary amino acids and phytochemicals have shown their ability for potential activation or inhibition of PPARs. Thus, through different mechanisms, all these nutrients can modulate PPARs and are ultimately helpful to prevent various metabolic disorders, particularly in transition dairy cows. This review aims to provide insights into the crucial role of PPARs in energy metabolism and their potential modulation through nutrigenomic interventions to improve energy homeostasis in dairy animals.
Collapse
|
8
|
Kiritsy MC, Ankley LM, Trombley J, Huizinga GP, Lord AE, Orning P, Elling R, Fitzgerald KA, Olive AJ. A genetic screen in macrophages identifies new regulators of IFNγ-inducible MHCII that contribute to T cell activation. eLife 2021; 10:65110. [PMID: 34747695 PMCID: PMC8598162 DOI: 10.7554/elife.65110] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 11/03/2021] [Indexed: 12/26/2022] Open
Abstract
Cytokine-mediated activation of host immunity is central to the control of pathogens. Interferon-gamma (IFNγ) is a key cytokine in protective immunity that induces major histocompatibility complex class II molecules (MHCII) to amplify CD4+ T cell activation and effector function. Despite its central role, the dynamic regulation of IFNγ-induced MHCII is not well understood. Using a genome-wide CRISPR-Cas9 screen in murine macrophages, we identified genes that control MHCII surface expression. Mechanistic studies uncovered two parallel pathways of IFNγ-mediated MHCII control that require the multifunctional glycogen synthase kinase three beta (GSK3β) or the mediator complex subunit 16 (MED16). Both pathways control distinct aspects of the IFNγ response and are necessary for IFNγ-mediated induction of the MHCII transactivator Ciita, MHCII expression, and CD4+ T cell activation. Our results define previously unappreciated regulation of MHCII expression that is required to control CD4+ T cell responses.
Collapse
Affiliation(s)
- Michael C Kiritsy
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Laurisa M Ankley
- Department of Microbiology & Molecular Genetics, College of Osteopathic Medicine, Michigan State University, East Lansing, United States
| | - Justin Trombley
- Department of Microbiology & Molecular Genetics, College of Osteopathic Medicine, Michigan State University, East Lansing, United States
| | - Gabrielle P Huizinga
- Department of Microbiology & Molecular Genetics, College of Osteopathic Medicine, Michigan State University, East Lansing, United States
| | - Audrey E Lord
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Pontus Orning
- Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Roland Elling
- Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Katherine A Fitzgerald
- Division of Infectious Disease and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Andrew J Olive
- Department of Microbiology & Molecular Genetics, College of Osteopathic Medicine, Michigan State University, East Lansing, United States
| |
Collapse
|
9
|
Structure of the human Mediator–RNA polymerase II pre-initiation complex. Nature 2021; 594:129-133. [DOI: 10.1038/s41586-021-03555-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 04/14/2021] [Indexed: 12/25/2022]
|
10
|
Hendel SJ, Shoulders MD. Directed evolution in mammalian cells. Nat Methods 2021; 18:346-357. [PMID: 33828274 DOI: 10.1038/s41592-021-01090-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 02/01/2021] [Accepted: 02/09/2021] [Indexed: 02/06/2023]
Abstract
Directed evolution experiments are typically carried out using in vitro systems, bacteria, or yeast-even when the goal is to probe or modulate mammalian biology. Performing directed evolution in systems that do not match the intended mammalian environment severely constrains the scope and functionality of the targets that can be evolved. We review new platforms that are now making it possible to use the mammalian cell itself as the setting for directed evolution and present an overview of frontier challenges and high-impact targets for this approach.
Collapse
Affiliation(s)
- Samuel J Hendel
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Matthew D Shoulders
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
11
|
Zhang Y, Shi C, Fu W, Gu X, Qi Z, Xu W, Xia G. Arabidopsis MED18 Interaction With RNA Pol IV and V Subunit NRPD2a in Transcriptional Regulation of Plant Immune Responses. FRONTIERS IN PLANT SCIENCE 2021; 12:692036. [PMID: 34691090 PMCID: PMC8527527 DOI: 10.3389/fpls.2021.692036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 09/10/2021] [Indexed: 05/02/2023]
Abstract
Mediator is a conserved multiprotein complex important for transcription by RNA polymerase II (Pol II). Arabidopsis Mediator subunit MED18 regulates flowering, hormone signaling and plant immunity. Here we report that Arabidopsis MED18 interacted with NUCLEAR RNA POLYMERASE D2a (NRPD2a), the second largest subunit of the nuclear Pol IV and V, which function in RNA-directed DNA methylation and epigenetic regulation of gene expression. Mutants for both MED18 and NRPD2a were compromised in resistance to necrotrophic fungal pathogen Botrytis cinerea. Mutants for NRPD1a, the largest subunit of Pol IV, were also compromised in resistance to Botrytis, supporting a critical role of Pol IV and V in plant defense against Botrytis. Increased Botrytis susceptibility of both the med18 and nrpd2a mutants were associated with reduced accumulation of reactive oxygen species, which are known to promote resistance to Botrytis. Both the basal and pathogen-induced levels of salicylic acid and jasmonic acid were also significantly altered in the med18 and nrpd2a mutants. Transcriptome profiling found that MED18 and NRPD2a affected both unique and overlapping sets of genes in a broad spectrum of biological processes and pathways that influence plant-pathogen interaction. The genes altered in expression in the med18 and nrpd2a mutants include disease resistance proteins, salicylic acid and jasmonic acid signaling and responses, which are known to affect resistance to necrotrophic pathogens. The novel interaction between subunits of Mediator and plant-specific RNA polymerases provides a new mechanism for epigenetic regulation of resistance and expression of defense-related genes in plant immunity.
Collapse
Affiliation(s)
- Yan Zhang
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, China
- *Correspondence: Yan Zhang,
| | - Chengchen Shi
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, China
| | - Weihong Fu
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, China
| | - Xiaojing Gu
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, China
| | - Ziyang Qi
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, China
| | - Weizhong Xu
- Lishui Academy of Agricultural and Forestry Sciences, Lishui, China
| | - Gengshou Xia
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, China
- Gengshou Xia,
| |
Collapse
|
12
|
Straub J, Venigalla S, Newman JJ. Mediator's Kinase Module: A Modular Regulator of Cell Fate. Stem Cells Dev 2020; 29:1535-1551. [PMID: 33161841 DOI: 10.1089/scd.2020.0164] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Selective gene expression is crucial in maintaining the self-renewing and multipotent properties of stem cells. Mediator is a large, evolutionarily conserved, multi-subunit protein complex that modulates gene expression by relaying signals from cell type-specific transcription factors to RNA polymerase II. In humans, this complex consists of 30 subunits arranged in four modules. One critical module of the Mediator complex is the kinase module consisting of four subunits: MED12, MED13, CDK8, and CCNC. The kinase module exists in variable association with the 26-subunit Mediator core and affects transcription through phosphorylation of transcription factors and by controlling Mediator structure and function. Many studies have shown the kinase module to be a key player in the maintenance of stem cells that is distinct from a general role in transcription. Genetic studies have revealed that dysregulation of this kinase subunit contributes to the development of many human diseases. In this review, we discuss the importance of the Mediator kinase module by examining how this module functions with the more recently identified transcriptional super-enhancers, how changes in the kinase module and its activity can lead to the development of human disease, and the role of this unique module in directing and maintaining cell state. As we look to use stem cells to understand human development and treat human disease through both cell-based therapies and tissue engineering, we need to remain aware of the on-going research and address critical gaps in knowledge related to the molecular mechanisms that control cell fate.
Collapse
Affiliation(s)
- Joseph Straub
- School of Biological Sciences, Louisiana Tech University, Ruston, Louisiana, USA
| | - Sree Venigalla
- School of Biological Sciences, Louisiana Tech University, Ruston, Louisiana, USA
| | - Jamie J Newman
- School of Biological Sciences, Louisiana Tech University, Ruston, Louisiana, USA
| |
Collapse
|
13
|
Mas A, Simón C. Molecular differential diagnosis of uterine leiomyomas and leiomyosarcomas. Biol Reprod 2020; 101:1115-1123. [PMID: 30184111 DOI: 10.1093/biolre/ioy195] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/13/2018] [Accepted: 08/30/2018] [Indexed: 12/18/2022] Open
Abstract
Uterine leiomyomas (LM) and leiomyosarcomas (LMS) are considered biologically unrelated tumors due to their cytogenetic and molecular disparity. Yet, these tumors share morphological and molecular characteristics that cannot be differentiated through current clinical diagnostic tests, and thus cannot be definitively classified as benign or malignant until surgery. Newer approaches are needed for the identification of these tumors, as has been done for other tissues. The application of next generation sequencing enables the detection of new mutations that, when coupled to machine learning bioinformatic tools, advances our understanding of chromosomal instability. These approaches in the context of LM and LMS could allow the discovery of genetic variants and possible genomic markers. Additionally, the potential clinical utility of circulating cell-free tumor DNA could revolutionize the noninvasive detection and monitoring of these tumors. Here, we seek to provide a perspective on the molecular background of LM and LMS, recognizing their distinct molecular features that may lead to improved diagnosis and personalized treatments, which would have a measurable impact on women's reproductive health.
Collapse
Affiliation(s)
- Aymara Mas
- Reproductive Medicine Research Group, La Fe Health Research Institute, Valencia, Spain.,Igenomix Foundation/Instituto de Investigación Sanitaria Hospital Clínico (INCLIVA), Valencia, Spain
| | - Carlos Simón
- Igenomix Foundation/Instituto de Investigación Sanitaria Hospital Clínico (INCLIVA), Valencia, Spain.,Department of Pediatrics, Obstetrics and Gynecology, University of Valencia, Valencia, Spain
| |
Collapse
|
14
|
Bylino OV, Ibragimov AN, Shidlovskii YV. Evolution of Regulated Transcription. Cells 2020; 9:E1675. [PMID: 32664620 PMCID: PMC7408454 DOI: 10.3390/cells9071675] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/07/2020] [Accepted: 07/10/2020] [Indexed: 12/12/2022] Open
Abstract
The genomes of all organisms abound with various cis-regulatory elements, which control gene activity. Transcriptional enhancers are a key group of such elements in eukaryotes and are DNA regions that form physical contacts with gene promoters and precisely orchestrate gene expression programs. Here, we follow gradual evolution of this regulatory system and discuss its features in different organisms. In eubacteria, an enhancer-like element is often a single regulatory element, is usually proximal to the core promoter, and is occupied by one or a few activators. Activation of gene expression in archaea is accompanied by the recruitment of an activator to several enhancer-like sites in the upstream promoter region. In eukaryotes, activation of expression is accompanied by the recruitment of activators to multiple enhancers, which may be distant from the core promoter, and the activators act through coactivators. The role of the general DNA architecture in transcription control increases in evolution. As a whole, it can be seen that enhancers of multicellular eukaryotes evolved from the corresponding prototypic enhancer-like regulatory elements with the gradually increasing genome size of organisms.
Collapse
Affiliation(s)
- Oleg V. Bylino
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilov St., 119334 Moscow, Russia; (O.V.B.); (A.N.I.)
| | - Airat N. Ibragimov
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilov St., 119334 Moscow, Russia; (O.V.B.); (A.N.I.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilov St., 119334 Moscow, Russia
| | - Yulii V. Shidlovskii
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilov St., 119334 Moscow, Russia; (O.V.B.); (A.N.I.)
- I.M. Sechenov First Moscow State Medical University, 8, bldg. 2 Trubetskaya St., 119048 Moscow, Russia
| |
Collapse
|
15
|
Wang Y, Liang H, Chen G, Liao C, Wang Y, Hu Z, Xie Q. Molecular and Phylogenetic Analyses of the Mediator Subunit Genes in Solanum lycopersicum. Front Genet 2019; 10:1222. [PMID: 31827491 PMCID: PMC6892441 DOI: 10.3389/fgene.2019.01222] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 11/05/2019] [Indexed: 11/19/2022] Open
Abstract
The Mediator complex is a multi-subunit protein assembly that serves as a central scaffold to help regulate DNA-binding transcription factors (TFs) and RNA polymerase II (Pol II) activity controlled gene expression programmed in response to developmental or environmental factors. However, litter information about Mediator complex subunit (MED) genes in tomato is available, although it is an essential model plant. In this study, we retrieved 46 candidate SlMED genes from the genome of tomato, and a comprehensive analysis was conducted, including their phylogenetic relationship, chromosomal locations, gene structure, cis-regulatory elements prediction, as well as gene expression. The expression profiling of 46 SlMED genes was analyzed using publicly available RNA-seq data. Furthermore, we selected some SlMED genes to evaluate their expression patterns in various tissues and under different abiotic stress treatments by quantitative reverse transcription PCR experiments. This is the first detailed report to elucidate the molecular and phylogenetic features of the MED genes in tomato, and it provides valuable clues for further functional analysis in order to clarify the role of the SlMED genes in diverse plant growth, development and abiotic stress response.
Collapse
Affiliation(s)
- Yunshu Wang
- Laboratory of Molecular Biology of Tomato, Bioengineering College, Chongqing University, Chongqing, China
| | - Honglian Liang
- Laboratory of Molecular Biology of Tomato, Bioengineering College, Chongqing University, Chongqing, China
| | - Guoping Chen
- Laboratory of Molecular Biology of Tomato, Bioengineering College, Chongqing University, Chongqing, China
| | - Changguang Liao
- Laboratory of Molecular Biology of Tomato, Bioengineering College, Chongqing University, Chongqing, China
| | - Yicong Wang
- Laboratory of Molecular Biology of Tomato, Bioengineering College, Chongqing University, Chongqing, China
| | - Zongli Hu
- Laboratory of Molecular Biology of Tomato, Bioengineering College, Chongqing University, Chongqing, China
| | - Qiaoli Xie
- Laboratory of Molecular Biology of Tomato, Bioengineering College, Chongqing University, Chongqing, China
| |
Collapse
|
16
|
Xiaoli AM, Song Z, Yang F. Lipogenic SREBP-1a/c transcription factors activate expression of the iron regulator hepcidin, revealing cross-talk between lipid and iron metabolisms. J Biol Chem 2019; 294:12743-12753. [PMID: 31270208 DOI: 10.1074/jbc.ra119.009644] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/01/2019] [Indexed: 12/17/2022] Open
Abstract
The sterol regulatory element-binding proteins (SREBPs) are a family of transcription factors best known for stimulating the expression of genes encoding key lipogenic enzymes. However, SREBP functions beyond lipid metabolism are less understood. Here, we show that hepcidin antimicrobial peptide (Hamp), encoding the hormone hepcidin essential for iron homeostasis and regulated by dietary iron and inflammation, is a target gene of the two SREBP isoforms SREBP-1a/c. We found that in tissue culture, mature, active, and nuclear forms of the SREBP-1a/c proteins induce endogenous Hamp gene expression and increase the Hamp promoter activity primarily via three regulatory sequences, including an E-box. Moreover, ChIP experiments revealed that SREBP-1a binds to the Hamp gene promoter. Overexpression of nuclear SREBP-1a under the control of the phosphoenolpyruvate carboxylase-1 (Pck1) promoter in mice increased hepatic Hamp mRNA and blood hepcidin levels, and as expected, caused fatty liver. Consistent with the known effects of Hamp up-regulation, SREBP-1a-overexpressing mice displayed signs of dysregulation in iron metabolism, including reduced serum iron and increased hepatic and splenic iron storage. Conversely, liver-specific depletion of the nuclear forms of SREBPs, as in SREBP cleavage-activating protein knockout mice, impaired lipopolysaccharide-induced up-regulation of hepatic Hamp Together, these results indicate that the SREBP-1a/c transcription regulators activate hepcidin expression and thereby contribute to the control of mammalian iron metabolism.
Collapse
Affiliation(s)
- Alus M Xiaoli
- Departments of Medicine and Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Ziyi Song
- Departments of Medicine and Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Fajun Yang
- Departments of Medicine and Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York 10461
| |
Collapse
|
17
|
Youn DY, Xiaoli AM, Kwon H, Yang F, Pessin JE. The subunit assembly state of the Mediator complex is nutrient-regulated and is dysregulated in a genetic model of insulin resistance and obesity. J Biol Chem 2019; 294:9076-9083. [PMID: 31028171 PMCID: PMC6556571 DOI: 10.1074/jbc.ra119.007850] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/18/2019] [Indexed: 01/22/2023] Open
Abstract
The Mediator complex plays a critical role in the regulation of transcription by linking transcription factors to RNA polymerase II. By examining mouse livers, we have found that in the fasted state, the Mediator complex exists primarily as an approximately 1.2-MDa complex, consistent with the size of the large Mediator complex, whereas following feeding, it converts to an approximately 600-kDa complex, consistent with the size of the core Mediator complex. This dynamic change is due to the dissociation and degradation of the kinase module that includes the MED13, MED12, cyclin-dependent kinase 8 (CDK8), and cyclin C (CCNC) subunits. The dissociation and degradation of the kinase module are dependent upon nutrient activation of mTORC1 that is necessary for the induction of lipogenic gene expression because pharmacological or genetic inhibition of mTORC1 in the fed state restores the kinase module. The degradation but not dissociation of the kinase module depends upon the E3 ligase, SCFFBW7 In addition, genetically insulin-resistant and obese db/db mice in the fasted state displayed elevated lipogenic gene expression and loss of the kinase module that was reversed following mTORC1 inhibition. These data demonstrate that the assembly state of the Mediator complex undergoes physiologic regulation during normal cycles of fasting and feeding in the mouse liver. Furthermore, the assembly state of the Mediator complex is dysregulated in states of obesity and insulin resistance.
Collapse
Affiliation(s)
- Dou Yeon Youn
- From the Departments of Medicine
- Molecular Pharmacology and
| | - Alus M Xiaoli
- From the Departments of Medicine
- Developmental and Molecular Biology, and
| | - Hyokjoon Kwon
- the Department of Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey 08901
| | - Fajun Yang
- From the Departments of Medicine
- Developmental and Molecular Biology, and
- the Fleischer Institute of Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, New York 10461 and
| | - Jeffrey E Pessin
- From the Departments of Medicine,
- Molecular Pharmacology and
- the Fleischer Institute of Diabetes and Metabolism, Albert Einstein College of Medicine, Bronx, New York 10461 and
| |
Collapse
|
18
|
Variants in MED12L, encoding a subunit of the mediator kinase module, are responsible for intellectual disability associated with transcriptional defect. Genet Med 2019; 21:2713-2722. [PMID: 31155615 PMCID: PMC7243155 DOI: 10.1038/s41436-019-0557-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/20/2019] [Indexed: 12/19/2022] Open
Abstract
Purpose Mediator is a multiprotein complex that allows the transfer of
genetic information from DNA binding proteins to the RNA polymerase II
during transcription initiation. MED12L is a subunit of the kinase module,
which is one of the four sub-complexes of the mediator complex. Other
subunits of the kinase module have been already implicated in intellectual
disability, namely MED12, MED13L, MED13 and CDK19. Methods We describe an international cohort of seven affected individuals
harboring variants involving MED12L identified by array
CGH, exome or genome sequencing. Results All affected individuals presented with intellectual disability
and/or developmental delay, including speech impairment. Other features
included autism spectrum disorder, aggressive behavior, corpus callosum
abnormality and mild facial morphological features. Three individuals had a
MED12L deletion or duplication. The other four
individuals harbored single nucleotide variants (one nonsense, one
frameshift and two splicing variants). Functional analysis confirmed a
moderate and significant alteration of RNA synthesis in two individuals. Conclusion Overall data suggest that MED12L haploinsufficiency is responsible
for intellectual disability and transcriptional defect. Our findings confirm
that the integrity of this kinase module is a critical factor for
neurological development.
Collapse
|
19
|
Rodrigues-Pousada C, Devaux F, Caetano SM, Pimentel C, da Silva S, Cordeiro AC, Amaral C. Yeast AP-1 like transcription factors (Yap) and stress response: a current overview. MICROBIAL CELL 2019; 6:267-285. [PMID: 31172012 PMCID: PMC6545440 DOI: 10.15698/mic2019.06.679] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Yeast adaptation to stress has been extensively studied. It involves large reprogramming of genome expression operated by many, more or less specific, transcription factors. Here, we review our current knowledge on the function of the eight Yap transcription factors (Yap1 to Yap8) in Saccharomyces cerevisiae, which were shown to be involved in various stress responses. More precisely, Yap1 is activated under oxidative stress, Yap2/Cad1 under cadmium, Yap4/Cin5 and Yap6 under osmotic shock, Yap5 under iron overload and Yap8/Arr1 by arsenic compounds. Yap3 and Yap7 seem to be involved in hydroquinone and nitrosative stresses, respectively. The data presented in this article illustrate how much knowledge on the function of these Yap transcription factors is advanced. The evolution of the Yap family and its roles in various pathogenic and non-pathogenic fungal species is discussed in the last section.
Collapse
Affiliation(s)
- Claudina Rodrigues-Pousada
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Frédéric Devaux
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, Laboratory of Computational and Quantitative Biology, F-75005, Paris, France
| | - Soraia M Caetano
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Catarina Pimentel
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Sofia da Silva
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Ana Carolina Cordeiro
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| | - Catarina Amaral
- Instituto de Tecnologia Química e Biológica Anónio Xavier, Universidade Nova de Lisboa, Avenida da República, EAN, Oeiras 2781-901, Oeiras, Portugal
| |
Collapse
|
20
|
Jaskolowski A, Iñigo S, Arellano SM, Arias LA, Fiol DF, Sede AR, Oldra MB, Lorenzi H, Muschietti JP, Pagnussat GC, Cerdán PD. The MED30 subunit of mediator complex is essential for early plant development and promotes flowering in Arabidopsis thaliana. Development 2019; 146:146/10/dev175224. [PMID: 31097434 DOI: 10.1242/dev.175224] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 04/15/2019] [Indexed: 02/05/2023]
Abstract
Mediator is a large multiprotein complex that is required for the transcription of most, if not all, genes transcribed by RNA Polymerase II. A core set of subunits is essential to assemble a functional Mediator in vitro and, therefore, the corresponding loss-of-function mutants are expected to be lethal. The MED30 subunit is essential in animal systems, but is absent in yeast. Here, we report that MED30 is also essential for both male gametophyte and embryo development in the model plant Arabidopsis thaliana Mutant med30 pollen grains were viable and some were able to germinate and target the ovules, although the embryos aborted shortly after fertilization, suggesting that MED30 is important for the paternal control of early embryo development. When gametophyte defects were bypassed by specific pollen complementation, loss of MED30 led to early embryo development arrest. Later in plant development, MED30 promotes flowering through multiple signaling pathways; its downregulation led to a phase change delay, downregulation of SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 3 (SPL3), FLOWERING LOCUS T (FTI) and SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1), and upregulation of FLOWERING LOCUS C (FLC).
Collapse
Affiliation(s)
- Aime Jaskolowski
- Fundación Instituto Leloir, IIBBA-CONICET, Avenida Patricias Argentinas 435, 1405-Buenos Aires, Argentina
| | - Sabrina Iñigo
- Fundación Instituto Leloir, IIBBA-CONICET, Avenida Patricias Argentinas 435, 1405-Buenos Aires, Argentina
| | - Sofía M Arellano
- Fundación Instituto Leloir, IIBBA-CONICET, Avenida Patricias Argentinas 435, 1405-Buenos Aires, Argentina
| | - Leonardo A Arias
- Instituto de Investigaciones Biológicas, IIB-CONICET- Universidad Nacional de Mar del Plata, Funes 3250 cuarto nivel, 7600, Mar del Plata, Argentina
| | - Diego F Fiol
- Instituto de Investigaciones Biológicas, IIB-CONICET- Universidad Nacional de Mar del Plata, Funes 3250 cuarto nivel, 7600, Mar del Plata, Argentina
| | - Ana R Sede
- Instituto de Ingeniería Genética y Biología Molecular 'Dr. Hector N. Torres', INGEBI-CONICET, Buenos Aires 1428, Argentina
| | - María B Oldra
- Fundación Instituto Leloir, IIBBA-CONICET, Avenida Patricias Argentinas 435, 1405-Buenos Aires, Argentina
| | | | - Jorge P Muschietti
- Instituto de Ingeniería Genética y Biología Molecular 'Dr. Hector N. Torres', INGEBI-CONICET, Buenos Aires 1428, Argentina.,Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires 1428, Argentina
| | - Gabriela C Pagnussat
- Instituto de Investigaciones Biológicas, IIB-CONICET- Universidad Nacional de Mar del Plata, Funes 3250 cuarto nivel, 7600, Mar del Plata, Argentina
| | - Pablo D Cerdán
- Fundación Instituto Leloir, IIBBA-CONICET, Avenida Patricias Argentinas 435, 1405-Buenos Aires, Argentina .,Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires 1428, Argentina
| |
Collapse
|
21
|
Twenty years of Mediator complex structural studies. Biochem Soc Trans 2019; 47:399-410. [PMID: 30733343 PMCID: PMC6393861 DOI: 10.1042/bst20180608] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 01/14/2019] [Accepted: 01/16/2019] [Indexed: 11/18/2022]
Abstract
Mediator is a large multiprotein complex conserved in all eukaryotes that plays an essential role in transcriptional regulation. Mediator comprises 25 subunits in yeast and 30 subunits in humans that form three main modules and a separable four-subunit kinase module. For nearly 20 years, because of its size and complexity, Mediator has posed a formidable challenge to structural biologists. The first two-dimensional electron microscopy (EM) projection map of Mediator leading to the canonical view of its division in three topological modules named Head, Middle and Tail, was published in 1999. Within the last few years, optimization of Mediator purification combined with technical and methodological advances in cryo-electron microscopy (cryo-EM) have revealed unprecedented details of Mediator subunit organization, interactions with RNA polymerase II and parts of its core structure at high resolution. To celebrate the twentieth anniversary of the first Mediator EM reconstruction, we look back on the structural studies of Mediator complex from a historical perspective and discuss them in the light of our current understanding of its role in transcriptional regulation.
Collapse
|
22
|
Role of Mediator in virulence and antifungal drug resistance in pathogenic fungi. Curr Genet 2019; 65:621-630. [DOI: 10.1007/s00294-019-00932-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 01/04/2019] [Accepted: 01/05/2019] [Indexed: 10/27/2022]
|
23
|
Martinez MF, Medrano S, Brown RI, Tufan T, Shang S, Bertoncello N, Guessoum O, Adli M, Belyea BC, Sequeira-Lopez MLS, Gomez RA. Super-enhancers maintain renin-expressing cell identity and memory to preserve multi-system homeostasis. J Clin Invest 2018; 128:4787-4803. [PMID: 30130256 PMCID: PMC6205391 DOI: 10.1172/jci121361] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 08/14/2018] [Indexed: 02/06/2023] Open
Abstract
Renin cells are crucial for survival - they control fluid-electrolyte and blood pressure homeostasis, vascular development, regeneration, and oxygen delivery to tissues. During embryonic development, renin cells are progenitors for multiple cell types that retain the memory of the renin phenotype. When there is a threat to survival, those descendants are transformed and reenact the renin phenotype to restore homeostasis. We tested the hypothesis that the molecular memory of the renin phenotype resides in unique regions and states of these cells' chromatin. Using renin cells at various stages of stimulation, we identified regions in the genome where the chromatin is open for transcription, mapped histone modifications characteristic of active enhancers such as H3K27ac, and tracked deposition of transcriptional activators such as Med1, whose deletion results in ablation of renin expression and low blood pressure. Using the rank ordering of super-enhancers, epigenetic rewriting, and enhancer deletion analysis, we found that renin cells harbor a unique set of super-enhancers that determine their identity. The most prominent renin super-enhancer may act as a chromatin sensor of signals that convey the physiologic status of the organism, and is responsible for the transformation of renin cell descendants to the renin phenotype, a fundamental process to ensure homeostasis.
Collapse
Affiliation(s)
| | | | | | - Turan Tufan
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Stephen Shang
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | | | - Omar Guessoum
- Child Health Research Center
- Department of Pediatrics
- Department of Biology, and
| | - Mazhar Adli
- Child Health Research Center
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | | | | | - R. Ariel Gomez
- Child Health Research Center
- Department of Pediatrics
- Department of Biology, and
| |
Collapse
|
24
|
Wang Y, Hu Z, Zhang J, Yu X, Guo JE, Liang H, Liao C, Chen G. Silencing SlMED18, tomato Mediator subunit 18 gene, restricts internode elongation and leaf expansion. Sci Rep 2018; 8:3285. [PMID: 29459728 PMCID: PMC5818486 DOI: 10.1038/s41598-018-21679-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 02/05/2018] [Indexed: 01/04/2023] Open
Abstract
Mediator complex, a conserved multi-protein, is necessary for controlling RNA polymerase II (Pol II) transcription in eukaryotes. Given little is known about them in tomato, a tomato Mediator subunit 18 gene was isolated and named SlMED18. To further explore the function of SlMED18, the transgenic tomato plants targeting SlMED18 by RNAi-mediated gene silencing were generated. The SlMED18-RNAi lines exhibited multiple developmental defects, including smaller size and slower growth rate of plant and significantly smaller compound leaves. The contents of endogenous bioactive GA3 in SlMED18 silenced lines were slightly less than that in wild type. Furthermore, qRT-PCR analysis indicated that expression of gibberellins biosynthesis genes such as SlGACPS and SlGA20x2, auxin transport genes (PIN1, PIN4, LAX1 and LAX2) and several key regulators, KNOX1, KNOX2, PHAN and LANCEOLATE(LA), which involved in the leaf morphogenesis were significantly down-regulated in SlMED18-RNAi lines. These results illustrated that SlMED18 plays an essential role in regulating plant internode elongation and leaf expansion in tomato plants and it acts as a key positive regulator of gibberellins biosynthesis and signal transduction as well as auxin proper transport signalling. These findings are the basis for understanding the function of the individual Mediator subunits in tomato.
Collapse
Affiliation(s)
- Yunshu Wang
- Laboratory of molecular biology of tomato, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Zongli Hu
- Laboratory of molecular biology of tomato, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Jianling Zhang
- Laboratory of molecular biology of tomato, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - XiaoHui Yu
- Laboratory of molecular biology of tomato, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Jun-E Guo
- Laboratory of molecular biology of tomato, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Honglian Liang
- Laboratory of molecular biology of tomato, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Changguang Liao
- Laboratory of molecular biology of tomato, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Guoping Chen
- Laboratory of molecular biology of tomato, Bioengineering College, Chongqing University, Chongqing, People's Republic of China.
| |
Collapse
|
25
|
Relating protein functional diversity to cell type number identifies genes that determine dynamic aspects of chromatin organisation as potential contributors to organismal complexity. PLoS One 2017; 12:e0185409. [PMID: 28945800 PMCID: PMC5612723 DOI: 10.1371/journal.pone.0185409] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/12/2017] [Indexed: 11/19/2022] Open
Abstract
Organismal complexity broadly relates to the number of different cell types within an organism and generally increases across a phylogeny. Whilst gene expression will underpin organismal complexity, it has long been clear that a simple count of gene number is not a sufficient explanation. In this paper, we use open-access information from the Ensembl databases to quantify the functional diversity of human genes that are broadly involved in transcription. Functional diversity is described in terms of the numbers of paralogues, protein isoforms and structural domains for each gene. The change in functional diversity is then calculated for up to nine orthologues from the nematode worm to human and correlated to the change in cell-type number. Those with the highest correlation are subject to gene ontology term enrichment and interaction analyses. We found that a range of genes that encode proteins associated with dynamic changes to chromatin are good candidates to contribute to organismal complexity.
Collapse
|
26
|
ScMED7, a sugarcane mediator subunit gene, acts as a regulator of plant immunity and is responsive to diverse stress and hormone treatments. Mol Genet Genomics 2017; 292:1363-1375. [DOI: 10.1007/s00438-017-1352-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Accepted: 07/27/2017] [Indexed: 10/19/2022]
|
27
|
Ono K, Banno H, Okaniwa M, Hirayama T, Iwamura N, Hikichi Y, Murai S, Hasegawa M, Hasegawa Y, Yonemori K, Hata A, Aoyama K, Cary DR. Design and synthesis of selective CDK8/19 dual inhibitors: Discovery of 4,5-dihydrothieno[3′,4′:3,4]benzo[1,2- d ]isothiazole derivatives. Bioorg Med Chem 2017; 25:2336-2350. [DOI: 10.1016/j.bmc.2017.02.038] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 02/17/2017] [Accepted: 02/17/2017] [Indexed: 12/29/2022]
|
28
|
Mediator, SWI/SNF and SAGA complexes regulate Yap8-dependent transcriptional activation of ACR2 in response to arsenate. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1860:472-481. [DOI: 10.1016/j.bbagrm.2017.02.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 01/30/2017] [Accepted: 02/01/2017] [Indexed: 01/12/2023]
|
29
|
Song Z, Xiaoli AM, Zhang Q, Zhang Y, Yang EST, Wang S, Chang R, Zhang ZD, Yang G, Strich R, Pessin JE, Yang F. Cyclin C regulates adipogenesis by stimulating transcriptional activity of CCAAT/enhancer-binding protein α. J Biol Chem 2017; 292:8918-8932. [PMID: 28351837 DOI: 10.1074/jbc.m117.776229] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 03/27/2017] [Indexed: 11/06/2022] Open
Abstract
Brown adipose tissue is important for maintaining energy homeostasis and adaptive thermogenesis in rodents and humans. As disorders arising from dysregulated energy metabolism, such as obesity and metabolic diseases, have increased, so has interest in the molecular mechanisms of adipocyte biology. Using a functional screen, we identified cyclin C (CycC), a conserved subunit of the Mediator complex, as a novel regulator for brown adipocyte formation. siRNA-mediated CycC knockdown (KD) in brown preadipocytes impaired the early transcriptional program of differentiation, and genetic KO of CycC completely blocked the differentiation process. RNA sequencing analyses of CycC-KD revealed a critical role of CycC in activating genes co-regulated by peroxisome proliferator activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα). Overexpression of PPARγ2 or addition of the PPARγ ligand rosiglitazone rescued the defects in CycC-KO brown preadipocytes and efficiently activated the PPARγ-responsive promoters in both WT and CycC-KO cells, suggesting that CycC is not essential for PPARγ transcriptional activity. In contrast, CycC-KO significantly reduced C/EBPα-dependent gene expression. Unlike for PPARγ, overexpression of C/EBPα could not induce C/EBPα target gene expression in CycC-KO cells or rescue the CycC-KO defects in brown adipogenesis, suggesting that CycC is essential for C/EBPα-mediated gene activation. CycC physically interacted with C/EBPα, and this interaction was required for C/EBPα transactivation domain activity. Consistent with the role of C/EBPα in white adipogenesis, CycC-KD also inhibited differentiation of 3T3-L1 cells into white adipocytes. Together, these data indicate that CycC activates adipogenesis in part by stimulating the transcriptional activity of C/EBPα.
Collapse
Affiliation(s)
- Ziyi Song
- From the Laboratory of Animal Fat Deposition and Muscle Development, Department of Animal Sciences, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China.,the Department of Medicine, Division of Endocrinology and Diabetes Research Center, and
| | - Alus M Xiaoli
- the Department of Medicine, Division of Endocrinology and Diabetes Research Center, and.,Departments of Developmental and Molecular Biology
| | | | - Yi Zhang
- the Department of Medicine, Division of Endocrinology and Diabetes Research Center, and.,Departments of Developmental and Molecular Biology
| | - Ellen S T Yang
- the Department of Medicine, Division of Endocrinology and Diabetes Research Center, and.,Departments of Developmental and Molecular Biology
| | - Sven Wang
- the Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029, and
| | - Rui Chang
- the Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029, and
| | | | - Gongshe Yang
- From the Laboratory of Animal Fat Deposition and Muscle Development, Department of Animal Sciences, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China,
| | - Randy Strich
- the Department of Molecular Biology, Rowan University School of Osteopathic Medicine, Stratford, New Jersey 08055
| | - Jeffrey E Pessin
- the Department of Medicine, Division of Endocrinology and Diabetes Research Center, and.,Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Fajun Yang
- the Department of Medicine, Division of Endocrinology and Diabetes Research Center, and .,Departments of Developmental and Molecular Biology
| |
Collapse
|
30
|
Hantsche M, Cramer P. Strukturelle Grundlage der Transkription: 10 Jahre nach dem Chemie-Nobelpreis. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201608066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Merle Hantsche
- Abteilung für Molekularbiologie; Max-Planck-Institut für biophysikalische Chemie; Am Fassberg 11 37077 Göttingen Deutschland
| | - Patrick Cramer
- Abteilung für Molekularbiologie; Max-Planck-Institut für biophysikalische Chemie; Am Fassberg 11 37077 Göttingen Deutschland
| |
Collapse
|
31
|
De novo mutations in genes of mediator complex causing syndromic intellectual disability: mediatorpathy or transcriptomopathy? Pediatr Res 2016; 80:809-815. [PMID: 27500536 DOI: 10.1038/pr.2016.162] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 06/13/2016] [Indexed: 12/24/2022]
Abstract
BACKGROUND Mutations in the X-linked gene MED12 cause at least three different, but closely related, entities of syndromic intellectual disability. Recently, a new syndrome caused by MED13L deleterious variants has been described, which shows similar clinical manifestations including intellectual disability, hypotonia, and other congenital anomalies. METHODS Genotyping of 1,256 genes related with neurodevelopment was performed by next-generation sequencing in three unrelated patients and their healthy parents. Clinically relevant findings were confirmed by conventional sequencing. RESULTS Each patient showed one de novo variant not previously reported in the literature or databases. Two different missense variants were found in the MED12 or MED13L genes and one nonsense mutation was found in the MED13L gene. CONCLUSION The phenotypic consequences of these mutations are closely related and/or have been previously reported in one or other gene. Additionally, MED12 and MED13L code for two closely related partners of the mediator kinase module. Consequently, we propose the concept of a common MED12/MED13L clinical spectrum, encompassing Opitz-Kaveggia syndrome, Lujan-Fryns syndrome, Ohdo syndrome, MED13L haploinsufficiency syndrome, and others.
Collapse
|
32
|
Hantsche M, Cramer P. The Structural Basis of Transcription: 10 Years After the Nobel Prize in Chemistry. Angew Chem Int Ed Engl 2016; 55:15972-15981. [DOI: 10.1002/anie.201608066] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Merle Hantsche
- Abteilung für Molekularbiologie; Max Planck Institut für biophysikalische Chemie; Am Fassberg 11 37077 Göttingen Germany
| | - Patrick Cramer
- Abteilung für Molekularbiologie; Max Planck Institut für biophysikalische Chemie; Am Fassberg 11 37077 Göttingen Germany
| |
Collapse
|
33
|
Regulation of metabolism by the Mediator complex. BIOPHYSICS REPORTS 2016; 2:69-77. [PMID: 28018965 PMCID: PMC5138257 DOI: 10.1007/s41048-016-0031-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 02/15/2016] [Indexed: 01/11/2023] Open
Abstract
The Mediator complex was originally discovered in yeast, but it is conserved in all eukaryotes. Its best-known function is to regulate RNA polymerase II-dependent gene transcription. Although the mechanisms by which the Mediator complex regulates transcription are often complicated by the context-dependent regulation, this transcription cofactor complex plays a pivotal role in numerous biological pathways. Biochemical, molecular, and physiological studies using cancer cell lines or model organisms have established the current paradigm of the Mediator functions. However, the physiological roles of the mammalian Mediator complex remain poorly defined, but have attracted a great interest in recent years. In this short review, we will summarize some of the reported functions of selective Mediator subunits in the regulation of metabolism. These intriguing findings suggest that the Mediator complex may be an important player in nutrient sensing and energy balance in mammals.
Collapse
|
34
|
Beagrie RA, Pombo A. Gene activation by metazoan enhancers: Diverse mechanisms stimulate distinct steps of transcription. Bioessays 2016; 38:881-93. [PMID: 27452946 DOI: 10.1002/bies.201600032] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Enhancers can stimulate transcription by a number of different mechanisms which control different stages of the transcription cycle of their target genes, from recruitment of the transcription machinery to elongation by RNA polymerase. These mechanisms may not be mutually exclusive, as a single enhancer may act through different pathways by binding multiple transcription factors. Multiple enhancers may also work together to regulate transcription of a shared target gene. Most of the evidence supporting different enhancer mechanisms comes from the study of single genes, but new high-throughput experimental frameworks offer the opportunity to integrate and generalize disparate mechanisms identified at single genes. This effort is especially important if we are to fully understand how sequence variation within enhancers contributes to human disease.
Collapse
Affiliation(s)
- Robert A Beagrie
- Epigenetic Regulation and Chromatin Architecture Group, Berlin Institute for Medical Systems Biology, Max-Delbrück Centre for Molecular Medicine, Berlin-Buch, Germany
| | - Ana Pombo
- Epigenetic Regulation and Chromatin Architecture Group, Berlin Institute for Medical Systems Biology, Max-Delbrück Centre for Molecular Medicine, Berlin-Buch, Germany
| |
Collapse
|
35
|
Kim MJ, Jang IC, Chua NH. The Mediator Complex MED15 Subunit Mediates Activation of Downstream Lipid-Related Genes by the WRINKLED1 Transcription Factor. PLANT PHYSIOLOGY 2016; 171:1951-64. [PMID: 27246098 PMCID: PMC4936590 DOI: 10.1104/pp.16.00664] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 05/30/2016] [Indexed: 05/20/2023]
Abstract
The Mediator complex is known to be a master coordinator of transcription by RNA polymerase II, and this complex is recruited by transcription factors (TFs) to target promoters for gene activation or repression. The plant-specific TF WRINKLED1 (WRI1) activates glycolysis-related and fatty acid biosynthetic genes during embryogenesis. However, no Mediator subunit has yet been identified that mediates WRI1 transcriptional activity. Promoter-β-glucuronidase fusion experiments showed that MEDIATOR15 (MED15) is expressed in the same cells in the embryo as WRI1. We found that the Arabidopsis (Arabidopsis thaliana) MED15 subunit of the Mediator complex interacts directly with WRI1 in the nucleus. Overexpression of MED15 or WRI1 increased transcript levels of WRI1 target genes involved in glycolysis and fatty acid biosynthesis; these genes were down-regulated in wild-type or WRI1-overexpressing plants by silencing of MED15 However, overexpression of MED15 in the wri1 mutant also increased transcript levels of WRI1 target genes, suggesting that MED15 also may act with other TFs to activate downstream lipid-related genes. Chromatin immunoprecipitation assays confirmed the association of MED15 with six WRI1 target gene promoters. Additionally, silencing of MED15 resulted in reduced fatty acid content in seedlings and mature seeds, whereas MED15 overexpression increased fatty acid content in both developmental stages. Similar results were found in wri1 mutant and WRI1 overexpression lines. Together, our results indicate that the WRI1/MED15 complex transcriptionally regulates glycolysis-related and fatty acid biosynthetic genes during embryogenesis.
Collapse
Affiliation(s)
- Mi Jung Kim
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604 (M.J.K., I.-C.J.); andLaboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10065 (N.-H.C.)
| | - In-Cheol Jang
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604 (M.J.K., I.-C.J.); andLaboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10065 (N.-H.C.)
| | - Nam-Hai Chua
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604 (M.J.K., I.-C.J.); andLaboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10065 (N.-H.C.)
| |
Collapse
|
36
|
Eukaryotic Transcription Regulation: Getting to the Heart of the Matter: Commentary on Mediator Architecture and RNA Polymerase II Function by Plaschka et al. J Mol Biol 2016; 428:2575-2580. [DOI: 10.1016/j.jmb.2016.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 11/18/2022]
|
37
|
Burr R, Stewart EV, Shao W, Zhao S, Hannibal-Bach HK, Ejsing CS, Espenshade PJ. Mga2 Transcription Factor Regulates an Oxygen-responsive Lipid Homeostasis Pathway in Fission Yeast. J Biol Chem 2016; 291:12171-83. [PMID: 27053105 DOI: 10.1074/jbc.m116.723650] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Indexed: 12/20/2022] Open
Abstract
Eukaryotic lipid synthesis is oxygen-dependent with cholesterol synthesis requiring 11 oxygen molecules and fatty acid desaturation requiring 1 oxygen molecule per double bond. Accordingly, organisms evaluate oxygen availability to control lipid homeostasis. The sterol regulatory element-binding protein (SREBP) transcription factors regulate lipid homeostasis. In mammals, SREBP-2 controls cholesterol biosynthesis, whereas SREBP-1 controls triacylglycerol and glycerophospholipid biosynthesis. In the fission yeast Schizosaccharomyces pombe, the SREBP-2 homolog Sre1 regulates sterol homeostasis in response to changing sterol and oxygen levels. However, notably missing is an SREBP-1 analog that regulates triacylglycerol and glycerophospholipid homeostasis in response to low oxygen. Consistent with this, studies have shown that the Sre1 transcription factor regulates only a fraction of all genes up-regulated under low oxygen. To identify new regulators of low oxygen adaptation, we screened the S. pombe nonessential haploid deletion collection and identified 27 gene deletions sensitive to both low oxygen and cobalt chloride, a hypoxia mimetic. One of these genes, mga2, is a putative transcriptional activator. In the absence of mga2, fission yeast exhibited growth defects under both normoxia and low oxygen conditions. Mga2 transcriptional targets were enriched for lipid metabolism genes, and mga2Δ cells showed disrupted triacylglycerol and glycerophospholipid homeostasis, most notably with an increase in fatty acid saturation. Indeed, addition of exogenous oleic acid to mga2Δ cells rescued the observed growth defects. Together, these results establish Mga2 as a transcriptional regulator of triacylglycerol and glycerophospholipid homeostasis in S. pombe, analogous to mammalian SREBP-1.
Collapse
Affiliation(s)
- Risa Burr
- From the Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
| | - Emerson V Stewart
- From the Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
| | - Wei Shao
- From the Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
| | - Shan Zhao
- From the Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
| | - Hans Kristian Hannibal-Bach
- the Department of Biochemistry and Molecular Biology, VILLUM Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense, Denmark
| | - Christer S Ejsing
- the Department of Biochemistry and Molecular Biology, VILLUM Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense, Denmark
| | - Peter J Espenshade
- From the Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 and
| |
Collapse
|
38
|
Chen L, Guan L, Qian P, Xu F, Wu Z, Wu Y, He K, Gou X, Li J, Hou S. NRPB3, the third largest subunit of RNA polymerase II, is essential for stomatal patterning and differentiation in Arabidopsis. Development 2016; 143:1600-11. [PMID: 26989174 PMCID: PMC4909857 DOI: 10.1242/dev.129098] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 03/03/2016] [Indexed: 12/22/2022]
Abstract
Stomata are highly specialized epidermal structures that control transpiration and gas exchange between plants and the environment. Signal networks underlying stomatal development have been previously uncovered but much less is known about how signals involved in stomatal development are transmitted to RNA polymerase II (Pol II or RPB), which plays a central role in the transcription of mRNA coding genes. Here, we identify a partial loss-of-function mutation of the third largest subunit of nuclear DNA-dependent Pol II (NRPB3) that exhibits an increased number of stomatal lineage cells and paired stomata. Phenotypic and genetic analyses indicated that NRPB3 is not only required for correct stomatal patterning, but is also essential for stomatal differentiation. Protein-protein interaction assays showed that NRPB3 directly interacts with two basic helix-loop-helix (bHLH) transcription factors, FAMA and INDUCER OF CBF EXPRESSION1 (ICE1), indicating that NRPB3 serves as an acceptor for signals from transcription factors involved in stomatal development. Our findings highlight the surprisingly conserved activating mechanisms mediated by the third largest subunit of Pol II in eukaryotes. Summary: RNA polymerase II subunit NRPB3 interacts with stomatal bHLH transcription factors FAMA and ICE1, connecting the stomatal development pathway to the general transcription machinery.
Collapse
Affiliation(s)
- Liang Chen
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Liping Guan
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Pingping Qian
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Fan Xu
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Zhongliang Wu
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Yujun Wu
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Kai He
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Xiaoping Gou
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Jia Li
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | - Suiwen Hou
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| |
Collapse
|
39
|
Huang PY, Catinot J, Zimmerli L. Ethylene response factors in Arabidopsis immunity. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:1231-41. [PMID: 26663391 DOI: 10.1093/jxb/erv518] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Pathogen attack leads to transcriptional changes and metabolic modifications allowing the establishment of appropriate plant defences. Transcription factors (TFs) are key players in plant innate immunity. Notably, ethylene response factor (ERF) TFs are integrators of hormonal pathways and are directly responsible for the transcriptional regulation of several jasmonate (JA)/ethylene (ET)-responsive defence genes. Transcriptional activation or repression by ERFs is achieved through the binding to JA/ET-responsive gene promoters. In this review, we describe the regulation and mode of action at a molecular level of ERFs involved in Arabidopsis thaliana immunity. In particular, we focus on defence activators such as ERF1, ORA59, ERF6, and the recently described ERF96.
Collapse
|
40
|
Thomas-Claudepierre AS, Robert I, Rocha PP, Raviram R, Schiavo E, Heyer V, Bonneau R, Luo VM, Reddy JK, Borggrefe T, Skok JA, Reina-San-Martin B. Mediator facilitates transcriptional activation and dynamic long-range contacts at the IgH locus during class switch recombination. J Exp Med 2016; 213:303-12. [PMID: 26903242 PMCID: PMC4813673 DOI: 10.1084/jem.20141967] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 01/15/2016] [Indexed: 12/21/2022] Open
Abstract
Thomas-Claudepierre et al. report that mediator facilitates the long-range contacts between acceptor switch regions and the IgH locus enhancers during class switch recombination and their transcriptional activation. Immunoglobulin (Ig) class switch recombination (CSR) is initiated by the transcription-coupled recruitment of activation-induced cytidine deaminase (AID) to Ig switch regions (S regions). During CSR, the IgH locus undergoes dynamic three-dimensional structural changes in which promoters, enhancers, and S regions are brought to close proximity. Nevertheless, little is known about the underlying mechanisms. In this study, we show that Med1 and Med12, two subunits of the mediator complex implicated in transcription initiation and long-range enhancer/promoter loop formation, are dynamically recruited to the IgH locus enhancers and the acceptor regions during CSR and that their knockdown in CH12 cells results in impaired CSR. Furthermore, we show that conditional inactivation of Med1 in B cells results in defective CSR and reduced acceptor S region transcription. Finally, we show that in B cells undergoing CSR, the dynamic long-range contacts between the IgH enhancers and the acceptor regions correlate with Med1 and Med12 binding and that they happen at a reduced frequency in Med1-deficient B cells. Our results implicate the mediator complex in the mechanism of CSR and are consistent with a model in which mediator facilitates the long-range contacts between S regions and the IgH locus enhancers during CSR and their transcriptional activation.
Collapse
Affiliation(s)
- Anne-Sophie Thomas-Claudepierre
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67400 Illkirch, France Institut National de la Santé et de la Recherche Médicale, Unité 964, 67404 Illkirch, France Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7104, 67404 Illkirch, France Université de Strasbourg, 67400 Illkirch, France
| | - Isabelle Robert
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67400 Illkirch, France Institut National de la Santé et de la Recherche Médicale, Unité 964, 67404 Illkirch, France Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7104, 67404 Illkirch, France Université de Strasbourg, 67400 Illkirch, France
| | - Pedro P Rocha
- Department of Pathology, School of Medicine, New York University, New York, NY 10003
| | - Ramya Raviram
- Department of Pathology, School of Medicine, New York University, New York, NY 10003 Department of Biology, New York University, New York, NY 10003
| | - Ebe Schiavo
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67400 Illkirch, France Institut National de la Santé et de la Recherche Médicale, Unité 964, 67404 Illkirch, France Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7104, 67404 Illkirch, France Université de Strasbourg, 67400 Illkirch, France
| | - Vincent Heyer
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67400 Illkirch, France Institut National de la Santé et de la Recherche Médicale, Unité 964, 67404 Illkirch, France Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7104, 67404 Illkirch, France Université de Strasbourg, 67400 Illkirch, France
| | - Richard Bonneau
- Department of Biology, New York University, New York, NY 10003 Department of Computer Science, Courant Institute of Mathematical Sciences, New York, NY 10003 Simons Center for Data Analysis, New York, NY 10010
| | - Vincent M Luo
- Department of Pathology, School of Medicine, New York University, New York, NY 10003 Department of Biology, New York University, New York, NY 10003
| | - Janardan K Reddy
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60208
| | | | - Jane A Skok
- Department of Pathology, School of Medicine, New York University, New York, NY 10003 New York University Cancer Institute, New York University, New York, NY 10003
| | - Bernardo Reina-San-Martin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67400 Illkirch, France Institut National de la Santé et de la Recherche Médicale, Unité 964, 67404 Illkirch, France Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7104, 67404 Illkirch, France Université de Strasbourg, 67400 Illkirch, France
| |
Collapse
|
41
|
Plaschka C, Nozawa K, Cramer P. Mediator Architecture and RNA Polymerase II Interaction. J Mol Biol 2016; 428:2569-2574. [PMID: 26851380 DOI: 10.1016/j.jmb.2016.01.028] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 01/26/2016] [Accepted: 01/27/2016] [Indexed: 12/18/2022]
Abstract
Integrated structural biology recently elucidated the architecture of Mediator and its position on RNA polymerase II. Here we summarize these achievements and list open questions on Mediator structure and mechanism.
Collapse
Affiliation(s)
- Clemens Plaschka
- Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Fassberg 11, 37077, Göttingen, Germany
| | - Kayo Nozawa
- Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Fassberg 11, 37077, Göttingen, Germany
| | - Patrick Cramer
- Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Fassberg 11, 37077, Göttingen, Germany.
| |
Collapse
|
42
|
Saint-André V, Federation AJ, Lin CY, Abraham BJ, Reddy J, Lee TI, Bradner JE, Young RA. Models of human core transcriptional regulatory circuitries. Genome Res 2016; 26:385-96. [PMID: 26843070 PMCID: PMC4772020 DOI: 10.1101/gr.197590.115] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Accepted: 12/21/2015] [Indexed: 01/06/2023]
Abstract
A small set of core transcription factors (TFs) dominates control of the gene expression program in embryonic stem cells and other well-studied cellular models. These core TFs collectively regulate their own gene expression, thus forming an interconnected auto-regulatory loop that can be considered the core transcriptional regulatory circuitry (CRC) for that cell type. There is limited knowledge of core TFs, and thus models of core regulatory circuitry, for most cell types. We recently discovered that genes encoding known core TFs forming CRCs are driven by super-enhancers, which provides an opportunity to systematically predict CRCs in poorly studied cell types through super-enhancer mapping. Here, we use super-enhancer maps to generate CRC models for 75 human cell and tissue types. These core circuitry models should prove valuable for further investigating cell-type–specific transcriptional regulation in healthy and diseased cells.
Collapse
Affiliation(s)
- Violaine Saint-André
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA
| | - Alexander J Federation
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Charles Y Lin
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Brian J Abraham
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA
| | - Jessica Reddy
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Tong Ihn Lee
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA
| | - James E Bradner
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA; Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Richard A Young
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
43
|
Kämpjärvi K, Kim NH, Keskitalo S, Clark AD, von Nandelstadh P, Turunen M, Heikkinen T, Park MJ, Mäkinen N, Kivinummi K, Lintula S, Hotakainen K, Nevanlinna H, Hokland P, Böhling T, Bützow R, Böhm J, Mecklin JP, Järvinen H, Kontro M, Visakorpi T, Taipale J, Varjosalo M, Boyer TG, Vahteristo P. Somatic MED12 mutations in prostate cancer and uterine leiomyomas promote tumorigenesis through distinct mechanisms. Prostate 2016; 76:22-31. [PMID: 26383637 DOI: 10.1002/pros.23092] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 08/31/2015] [Indexed: 11/08/2022]
Abstract
BACKGROUND Mediator is a multiprotein interface between eukaryotic gene-specific transcription factors and RNA polymerase II. Mutations in exon 2 of the gene encoding MED12, a key subunit of the regulatory kinase module in Mediator, are extremely frequent in uterine leiomyomas, breast fibroadenomas, and phyllodes tumors. These mutations disrupt kinase module interactions and lead to diminished Mediator-associated kinase activity. MED12 mutations in exon 26, resulting in a substitution of leucine 1224 to phenylalanine (L1224F), have been recurrently observed in prostate cancer. METHODS To elucidate the molecular mechanisms leading to tumorigenesis in prostate cancer, we analyzed global interaction profiles of wild-type and L1224F mutant MED12 with quantitative affinity purification-mass spectrometry (AP-MS). Immunoprecipitation and kinase activity assay were used to further assess the interactions between Mediator complex subunits and kinase activity. The presence of L1224F mutation was analyzed in altogether 877 samples representing prostate hyperplasia, prostate cancer, and various tumor types in which somatic MED12 mutations have previously been observed. RESULTS In contrast to N-terminal MED12 mutations observed in uterine leiomyomas, the L1224F mutation compromises neither the interaction of MED12 with kinase module subunits Cyclin C and CDK8/19 nor Mediator-associated CDK activity. Instead, the L1224F mutation was shown to affect interactions between MED12 and other Mediator components (MED1, MED13, MED13L, MED14, MED15, MED17, and MED24). Mutation screening revealed one mutation in a Finnish (Caucasian) prostate cancer patient, whereas no mutations in any other tumor type were observed. CONCLUSIONS Specific somatic MED12 mutations in prostate cancer and uterine leiomyomas accumulate in two separate regions of the gene and promote tumorigenesis through clearly distinct mechanisms.
Collapse
Affiliation(s)
- Kati Kämpjärvi
- Genome-Scale Biology Research Program and Department of Medical and Clinical Genetics, University of Helsinki, Helsinki, Finland
| | - Nam Hee Kim
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Salla Keskitalo
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Alison D Clark
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Pernilla von Nandelstadh
- Genome-Scale Biology Research Program and Department of Pathology, University of Helsinki, Helsinki, Finland
| | - Mikko Turunen
- Genome-Scale Biology Research Program and Department of Pathology, University of Helsinki, Helsinki, Finland
| | - Tuomas Heikkinen
- Genome-Scale Biology Research Program and Department of Medical and Clinical Genetics, University of Helsinki, Helsinki, Finland
| | - Min Ju Park
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Netta Mäkinen
- Genome-Scale Biology Research Program and Department of Medical and Clinical Genetics, University of Helsinki, Helsinki, Finland
| | - Kati Kivinummi
- Institute of Biosciences and Medical Technology - BioMediTech and Fimlab Laboratories, University of Tampere and Tampere University Hospital, Tampere, Finland
| | - Susanna Lintula
- Department of Clinical Chemistry, University of Helsinki, Helsinki, Finland
| | | | - Heli Nevanlinna
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Peter Hokland
- Department of Hematology, Aarhus University Hospital, Aarhus, Denmark
| | - Tom Böhling
- Department of Pathology, The Laboratory of Helsinki University Central Hospital (HUSLAB), Helsinki University Central Hospital and Medicum, University of Helsinki, Helsinki, Finland
| | - Ralf Bützow
- Department of Pathology, The Laboratory of Helsinki University Central Hospital (HUSLAB), Helsinki University Central Hospital and Medicum, University of Helsinki, Helsinki, Finland
| | - Jan Böhm
- Department of Pathology, Jyväskylä Central Hospital, Jyväskylä, Finland
| | - Jukka-Pekka Mecklin
- Department of Surgery, Jyväskylä Central Hospital and University of Eastern Finland, Jyväskylä, Finland
| | - Heikki Järvinen
- Department of Surgery, Helsinki University Central Hospital, Helsinki, Finland
| | - Mika Kontro
- Hematology Research Unit Helsinki, Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland
| | - Tapio Visakorpi
- Institute of Biosciences and Medical Technology - BioMediTech and Fimlab Laboratories, University of Tampere and Tampere University Hospital, Tampere, Finland
| | - Jussi Taipale
- Genome-Scale Biology Research Program and Department of Pathology, University of Helsinki, Helsinki, Finland
| | - Markku Varjosalo
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Thomas G Boyer
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - Pia Vahteristo
- Genome-Scale Biology Research Program and Department of Medical and Clinical Genetics, University of Helsinki, Helsinki, Finland
| |
Collapse
|
44
|
Li HJ, Zhu SS, Zhang MX, Wang T, Liang L, Xue Y, Shi DQ, Liu J, Yang WC. Arabidopsis CBP1 Is a Novel Regulator of Transcription Initiation in Central Cell-Mediated Pollen Tube Guidance. THE PLANT CELL 2015; 27:2880-93. [PMID: 26462908 PMCID: PMC4682316 DOI: 10.1105/tpc.15.00370] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 09/22/2015] [Indexed: 05/04/2023]
Abstract
In flowering plants, sperm cells are delivered to the embryo sac by a pollen tube guided by female signals. Both the gametic and synergid cells contribute to pollen tube attraction. Synergids secrete peptide signals that lure the tube, while the role of the gametic cells is unknown. Previously, we showed that CENTRAL CELL GUIDANCE (CCG) is essential for pollen tube attraction in Arabidopsis thaliana, but the molecular mechanism is unclear. Here, we identified CCG BINDING PROTEIN1 (CBP1) and demonstrated that it interacts with CCG, Mediator subunits, RNA polymerase II (Pol II), and central cell-specific AGAMOUS-like transcription factors. In addition, CCG interacts with TATA-box Binding Protein 1 and Pol II as a TFIIB-like transcription factor. CBP1-knockdown ovules are defective in pollen tube attraction. Expression profiling revealed that cysteine-rich peptide (CRP) transcripts were downregulated in ccg ovules. CCG and CBP1 coregulate a subset of CRPs in the central cell and the synergids, including the attractant LURE1. CBP1 is extensively expressed in multiple vegetative tissues and specifically in the central cell in reproductive growth. We propose that CBP1, via interaction with CCG and the Mediator complex, connects transcription factors and the Pol II machinery to regulate pollen tube attraction.
Collapse
Affiliation(s)
- Hong-Ju Li
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Shan-Shan Zhu
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Meng-Xia Zhang
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tong Wang
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liang Liang
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yong Xue
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dong-Qiao Shi
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jie Liu
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Wei-Cai Yang
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| |
Collapse
|
45
|
Robinson PJ, Trnka MJ, Pellarin R, Greenberg CH, Bushnell DA, Davis R, Burlingame AL, Sali A, Kornberg RD. Molecular architecture of the yeast Mediator complex. eLife 2015; 4. [PMID: 26402457 PMCID: PMC4631838 DOI: 10.7554/elife.08719] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 09/23/2015] [Indexed: 12/18/2022] Open
Abstract
The 21-subunit Mediator complex transduces regulatory information from enhancers to promoters, and performs an essential role in the initiation of transcription in all eukaryotes. Structural information on two-thirds of the complex has been limited to coarse subunit mapping onto 2-D images from electron micrographs. We have performed chemical cross-linking and mass spectrometry, and combined the results with information from X-ray crystallography, homology modeling, and cryo-electron microscopy by an integrative modeling approach to determine a 3-D model of the entire Mediator complex. The approach is validated by the use of X-ray crystal structures as internal controls and by consistency with previous results from electron microscopy and yeast two-hybrid screens. The model shows the locations and orientations of all Mediator subunits, as well as subunit interfaces and some secondary structural elements. Segments of 20–40 amino acid residues are placed with an average precision of 20 Å. The model reveals roles of individual subunits in the organization of the complex. DOI:http://dx.doi.org/10.7554/eLife.08719.001 Inside a cell, proteins are made from instructions encoded by DNA. To produce a particular protein, a section of DNA within a gene is copied into a molecule of messenger ribonucleic acid (or mRNA). This process is called transcription and is carried out by an enzyme known as RNA polymerase. Transcription begins in a region of DNA called a promoter, which is found at the start of the gene. RNA polymerase is brought to the DNA by many proteins, including the so-called Mediator complex. Mediator receives signals from within the cell and from the environment, processes the information, and instructs RNA polymerase whether to transcribe the gene or not. Mediator performs this important role in all organisms from yeast to humans, but it is not clear how it works. A crucial step towards the solution of this problem is to understand the three-dimensional structure of the complex. Previous research using a technique called ‘electron microscopy’ showed that Mediator is composed of three modules, referred to as Head, Middle and Tail. The images from electron microscopy were not sufficiently detailed to reveal the organization of the proteins within these modules. An open-source Integrative Modeling Platform (IMP for short) was recently developed to arrive at structural models of large protein complexes from a combination of experimental data and computer models. Now, Robinson, Trnka, Pellarin et al. have used this platform to study the Mediator complex. First, Robinson, Trnka, Pellarin et al. collected experimental data on the structure of the Mediator complex using two approaches called ‘chemical cross-linking’ and ‘mass spectrometry’. This data was combined with biochemical and structural information from previous studies to generate a three-dimensional model of the structure of the entire Mediator using IMP. The model is detailed enough to show the location and orientation of all the proteins in the complex. For example, a protein called Med17 connects the Head and Middle modules, while another subunit—known as Med14—spans the entire complex and makes extensive contacts with other proteins in all three modules. DOI:http://dx.doi.org/10.7554/eLife.08719.002
Collapse
Affiliation(s)
- Philip J Robinson
- Department of Structural Biology, Stanford University School of Medicine, Stanford, United States
| | - Michael J Trnka
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
| | - Riccardo Pellarin
- Department of Bioengineering and Therapeutic Sciences, Department of Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, United States.,Structural Bioinformatics Unit, Paris, France
| | - Charles H Greenberg
- Department of Bioengineering and Therapeutic Sciences, Department of Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, United States
| | - David A Bushnell
- Department of Structural Biology, Stanford University School of Medicine, Stanford, United States
| | - Ralph Davis
- Department of Structural Biology, Stanford University School of Medicine, Stanford, United States
| | - Alma L Burlingame
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, Department of Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, United States
| | - Roger D Kornberg
- Department of Structural Biology, Stanford University School of Medicine, Stanford, United States
| |
Collapse
|
46
|
Wang C, Yao J, Du X, Zhang Y, Sun Y, Rollins JA, Mou Z. The Arabidopsis Mediator Complex Subunit16 Is a Key Component of Basal Resistance against the Necrotrophic Fungal Pathogen Sclerotinia sclerotiorum. PLANT PHYSIOLOGY 2015; 169:856-72. [PMID: 26143252 PMCID: PMC4577384 DOI: 10.1104/pp.15.00351] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 07/01/2015] [Indexed: 05/19/2023]
Abstract
Although Sclerotinia sclerotiorum is a devastating necrotrophic fungal plant pathogen in agriculture, the virulence mechanisms utilized by S. sclerotiorum and the host defense mechanisms against this pathogen have not been fully understood. Here, we report that the Arabidopsis (Arabidopsis thaliana) Mediator complex subunit MED16 is a key component of basal resistance against S. sclerotiorum. Mutants of MED16 are markedly more susceptible to S. sclerotiorum than mutants of 13 other Mediator subunits, and med16 has a much stronger effect on S. sclerotiorum-induced transcriptome changes compared with med8, a mutation not altering susceptibility to S. sclerotiorum. Interestingly, med16 is also more susceptible to S. sclerotiorum than coronatine-insensitive1-1 (coi1-1), which is the most susceptible mutant reported so far. Although the jasmonic acid (JA)/ethylene (ET) defense pathway marker gene PLANT DEFENSIN1.2 (PDF1.2) cannot be induced in either med16 or coi1-1, basal transcript levels of PDF1.2 in med16 are significantly lower than in coi1-1. Furthermore, ET-induced suppression of JA-activated wound responses is compromised in med16, suggesting a role for MED16 in JA-ET cross talk. Additionally, MED16 is required for the recruitment of RNA polymerase II to PDF1.2 and OCTADECANOID-RESPONSIVE ARABIDOPSIS ETHYLENE/ETHYLENE-RESPONSIVE FACTOR59 (ORA59), two target genes of both JA/ET-mediated and the transcription factor WRKY33-activated defense pathways. Finally, MED16 is physically associated with WRKY33 in yeast and in planta, and WRKY33-activated transcription of PDF1.2 and ORA59 as well as resistance to S. sclerotiorum depends on MED16. Taken together, these results indicate that MED16 regulates resistance to S. sclerotiorum by governing both JA/ET-mediated and WRKY33-activated defense signaling in Arabidopsis.
Collapse
Affiliation(s)
- Chenggang Wang
- Department of Microbiology and Cell Science (C.W., Z.M.) and Department of Plant Pathology (J.A.R.), University of Florida, Gainesville, Florida 32611;Department of Microbiology and Immunology, University of Buffalo, Buffalo, New York 14203 (J.Y., Y.S.);College of Life Science, Hubei University, Wuhan 430062, China (X.D.); andInterdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32601 (Y.Z.)
| | - Jin Yao
- Department of Microbiology and Cell Science (C.W., Z.M.) and Department of Plant Pathology (J.A.R.), University of Florida, Gainesville, Florida 32611;Department of Microbiology and Immunology, University of Buffalo, Buffalo, New York 14203 (J.Y., Y.S.);College of Life Science, Hubei University, Wuhan 430062, China (X.D.); andInterdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32601 (Y.Z.)
| | - Xuezhu Du
- Department of Microbiology and Cell Science (C.W., Z.M.) and Department of Plant Pathology (J.A.R.), University of Florida, Gainesville, Florida 32611;Department of Microbiology and Immunology, University of Buffalo, Buffalo, New York 14203 (J.Y., Y.S.);College of Life Science, Hubei University, Wuhan 430062, China (X.D.); andInterdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32601 (Y.Z.)
| | - Yanping Zhang
- Department of Microbiology and Cell Science (C.W., Z.M.) and Department of Plant Pathology (J.A.R.), University of Florida, Gainesville, Florida 32611;Department of Microbiology and Immunology, University of Buffalo, Buffalo, New York 14203 (J.Y., Y.S.);College of Life Science, Hubei University, Wuhan 430062, China (X.D.); andInterdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32601 (Y.Z.)
| | - Yijun Sun
- Department of Microbiology and Cell Science (C.W., Z.M.) and Department of Plant Pathology (J.A.R.), University of Florida, Gainesville, Florida 32611;Department of Microbiology and Immunology, University of Buffalo, Buffalo, New York 14203 (J.Y., Y.S.);College of Life Science, Hubei University, Wuhan 430062, China (X.D.); andInterdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32601 (Y.Z.)
| | - Jeffrey A Rollins
- Department of Microbiology and Cell Science (C.W., Z.M.) and Department of Plant Pathology (J.A.R.), University of Florida, Gainesville, Florida 32611;Department of Microbiology and Immunology, University of Buffalo, Buffalo, New York 14203 (J.Y., Y.S.);College of Life Science, Hubei University, Wuhan 430062, China (X.D.); andInterdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32601 (Y.Z.)
| | - Zhonglin Mou
- Department of Microbiology and Cell Science (C.W., Z.M.) and Department of Plant Pathology (J.A.R.), University of Florida, Gainesville, Florida 32611;Department of Microbiology and Immunology, University of Buffalo, Buffalo, New York 14203 (J.Y., Y.S.);College of Life Science, Hubei University, Wuhan 430062, China (X.D.); andInterdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32601 (Y.Z.)
| |
Collapse
|
47
|
Clark AD, Oldenbroek M, Boyer TG. Mediator kinase module and human tumorigenesis. Crit Rev Biochem Mol Biol 2015; 50:393-426. [PMID: 26182352 DOI: 10.3109/10409238.2015.1064854] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mediator is a conserved multi-subunit signal processor through which regulatory informatiosn conveyed by gene-specific transcription factors is transduced to RNA Polymerase II (Pol II). In humans, MED13, MED12, CDK8 and Cyclin C (CycC) comprise a four-subunit "kinase" module that exists in variable association with a 26-subunit Mediator core. Genetic and biochemical studies have established the Mediator kinase module as a major ingress of developmental and oncogenic signaling through Mediator, and much of its function in signal-dependent gene regulation derives from its resident CDK8 kinase activity. For example, CDK8-targeted substrate phosphorylation impacts transcription factor half-life, Pol II activity and chromatin chemistry and functional status. Recent structural and biochemical studies have revealed a precise network of physical and functional subunit interactions required for proper kinase module activity. Accordingly, pathologic change in this activity through altered expression or mutation of constituent kinase module subunits can have profound consequences for altered signaling and tumor formation. Herein, we review the structural organization, biological function and oncogenic potential of the Mediator kinase module. We focus principally on tumor-associated alterations in kinase module subunits for which mechanistic relationships as opposed to strictly correlative associations are established. These considerations point to an emerging picture of the Mediator kinase module as an oncogenic unit, one in which pathogenic activation/deactivation through component change drives tumor formation through perturbation of signal-dependent gene regulation. It follows that therapeutic strategies to combat CDK8-driven tumors will involve targeted modulation of CDK8 activity or pharmacologic manipulation of dysregulated CDK8-dependent signaling pathways.
Collapse
Affiliation(s)
- Alison D Clark
- a Department of Molecular Medicine , Institute of Biotechnology, University of Texas Health Science Center at San Antonio , San Antonio , TX , USA
| | - Marieke Oldenbroek
- a Department of Molecular Medicine , Institute of Biotechnology, University of Texas Health Science Center at San Antonio , San Antonio , TX , USA
| | - Thomas G Boyer
- a Department of Molecular Medicine , Institute of Biotechnology, University of Texas Health Science Center at San Antonio , San Antonio , TX , USA
| |
Collapse
|
48
|
Plaschka C, Larivière L, Wenzeck L, Seizl M, Hemann M, Tegunov D, Petrotchenko EV, Borchers CH, Baumeister W, Herzog F, Villa E, Cramer P. Architecture of the RNA polymerase II-Mediator core initiation complex. Nature 2015; 518:376-80. [PMID: 25652824 DOI: 10.1038/nature14229] [Citation(s) in RCA: 219] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 01/14/2015] [Indexed: 12/12/2022]
Abstract
The conserved co-activator complex Mediator enables regulated transcription initiation by RNA polymerase (Pol) II. Here we reconstitute an active 15-subunit core Mediator (cMed) comprising all essential Mediator subunits from Saccharomyces cerevisiae. The cryo-electron microscopic structure of cMed bound to a core initiation complex was determined at 9.7 Å resolution. cMed binds Pol II around the Rpb4-Rpb7 stalk near the carboxy-terminal domain (CTD). The Mediator head module binds the Pol II dock and the TFIIB ribbon and stabilizes the initiation complex. The Mediator middle module extends to the Pol II foot with a 'plank' that may influence polymerase conformation. The Mediator subunit Med14 forms a 'beam' between the head and middle modules and connects to the tail module that is predicted to bind transcription activators located on upstream DNA. The Mediator 'arm' and 'hook' domains contribute to a 'cradle' that may position the CTD and TFIIH kinase to stimulate Pol II phosphorylation.
Collapse
Affiliation(s)
- C Plaschka
- Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| | - L Larivière
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - L Wenzeck
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - M Seizl
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - M Hemann
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - D Tegunov
- Max Planck Institute for Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - E V Petrotchenko
- Department of Biochemistry and Microbiology, Genome British Columbia Protein Centre, University of Victoria, 3101-4464 Markham Street, Victoria, British Columbia V8Z7X8, Canada
| | - C H Borchers
- Department of Biochemistry and Microbiology, Genome British Columbia Protein Centre, University of Victoria, 3101-4464 Markham Street, Victoria, British Columbia V8Z7X8, Canada
| | - W Baumeister
- Max Planck Institute for Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - F Herzog
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - E Villa
- 1] Max Planck Institute for Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany [2] Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA
| | - P Cramer
- Max Planck Institute for Biophysical Chemistry, Department of Molecular Biology, Am Fassberg 11, 37077 Göttingen, Germany
| |
Collapse
|
49
|
Salicylic Acid Signaling in Plant Innate Immunity. PLANT HORMONE SIGNALING SYSTEMS IN PLANT INNATE IMMUNITY 2015. [DOI: 10.1007/978-94-017-9285-1_2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
50
|
A functional portrait of Med7 and the mediator complex in Candida albicans. PLoS Genet 2014; 10:e1004770. [PMID: 25375174 PMCID: PMC4222720 DOI: 10.1371/journal.pgen.1004770] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 09/22/2014] [Indexed: 11/19/2022] Open
Abstract
Mediator is a multi-subunit protein complex that regulates gene expression in eukaryotes by integrating physiological and developmental signals and transmitting them to the general RNA polymerase II machinery. We examined, in the fungal pathogen Candida albicans, a set of conditional alleles of genes encoding Mediator subunits of the head, middle, and tail modules that were found to be essential in the related ascomycete Saccharomyces cerevisiae. Intriguingly, while the Med4, 8, 10, 11, 14, 17, 21 and 22 subunits were essential in both fungi, the structurally highly conserved Med7 subunit was apparently non-essential in C. albicans. While loss of CaMed7 did not lead to loss of viability under normal growth conditions, it dramatically influenced the pathogen's ability to grow in different carbon sources, to form hyphae and biofilms, and to colonize the gastrointestinal tracts of mice. We used epitope tagging and location profiling of the Med7 subunit to examine the distribution of the DNA sites bound by Mediator during growth in either the yeast or the hyphal form, two distinct morphologies characterized by different transcription profiles. We observed a core set of 200 genes bound by Med7 under both conditions; this core set is expanded moderately during yeast growth, but is expanded considerably during hyphal growth, supporting the idea that Mediator binding correlates with changes in transcriptional activity and that this binding is condition specific. Med7 bound not only in the promoter regions of active genes but also within coding regions and at the 3′ ends of genes. By combining genome-wide location profiling, expression analyses and phenotyping, we have identified different Med7p-influenced regulons including genes related to glycolysis and the Filamentous Growth Regulator family. In the absence of Med7, the ribosomal regulon is de-repressed, suggesting Med7 is involved in central aspects of growth control. In this study, we have investigated Mediator function in the human fungal pathogen C. albicans. An initial screening of conditionally regulated Mediator subunits showed that the Med7 of C. albicans was not essential, in contrast to the situation noted for S. cerevisiae. While loss of CaMed7 did not lead to loss of viability under normal growth conditions, it dramatically influenced the pathogen's ability to grow in different carbon sources, to form hyphae and biofilms, and to colonize the gastrointestinal tracts of mice. We used location profiling to determine Mediator binding under yeast and hyphal morphologies characterized by different transcription profiles. We observed a core set of specific and common genes bound by Med7 under both conditions; this specific core set is expanded considerably during hyphal growth, supporting the idea that Mediator binding correlates with changes in transcriptional activity and that this binding is condition specific. Med7 bound not only in the promoter regions of active genes but also of inactive genes and within coding regions and at the 3′ ends of genes. By combining genome-wide location profiling, expression analyses and phenotyping, we have identified different Med7 regulons including genes related to glycolysis and the Filamentous Growth Regulator family.
Collapse
|