1
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Xu X, Qiao D, Brasier AR. Cooperative interaction of interferon regulatory factor -1 and bromodomain-containing protein 4 on RNA polymerase activation for intrinsic innate immunity. Front Immunol 2024; 15:1366235. [PMID: 38601157 PMCID: PMC11004252 DOI: 10.3389/fimmu.2024.1366235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 03/14/2024] [Indexed: 04/12/2024] Open
Abstract
Introduction The human orthopneumovirus, Respiratory Syncytial Virus (RSV), is the causative agent of severe lower respiratory tract infections (LRTI) and exacerbations of chronic lung diseases. In immune competent hosts, RSV productively infects highly differentiated epithelial cells, where it elicits robust anti-viral, cytokine and remodeling programs. By contrast, basal cells are relatively resistant to RSV infection, in part, because of constitutive expression of an intrinsic innate immune response (IIR) consisting of a subgroup of interferon (IFN) responsive genes. The mechanisms controlling the intrinsic IIR are not known. Methods Here, we use human small airway epithelial cell hSAECs as a multipotent airway stem cell model to examine regulatory control of an intrinsic IIR pathway. Results We find hSAECs express patterns of intrinsic IIRs, highly conserved with pluri- and multi-potent stem cells. We demonstrate a core intrinsic IIR network consisting of Bone Marrow Stromal Cell Antigen 2 (Bst2), Interferon Induced Transmembrane Protein 1 (IFITM1) and Toll-like receptor (TLR3) expression are directly under IRF1 control. Moreover, expression of this intrinsic core is rate-limited by ambient IRF1• phospho-Ser 2 CTD RNA Polymerase II (pSer2 Pol II) complexes binding to their proximal promoters. In response to RSV infection, the abundance of IRF1 and pSer2 Pol II binding is dramatically increased, with IRF1 complexing to the BRD4 chromatin remodeling complex (CRC). Using chromatin immunoprecipitation in IRF1 KD cells, we find that the binding of BRD4 is IRF1 independent. Using a small molecule inhibitor of the BRD4 acetyl lysine binding bromodomain (BRD4i), we further find that BRD4 bromodomain interactions are required for stable BRD4 promoter binding to the intrinsic IIR core promoters, as well as for RSV-inducible pSer2 Pol II recruitment. Surprisingly, BRD4i does not disrupt IRF1-BRD4 interactions, but disrupts both RSV-induced BRD4 and IRF1 interactions with pSer2 Pol II. Conclusions We conclude that the IRF1 functions in two modes- in absence of infection, ambient IRF1 mediates constitutive expression of the intrinsic IIR, whereas in response to RSV infection, the BRD4 CRC independently activates pSer2 Pol II to mediates robust expression of the intrinsic IIR. These data provide insight into molecular control of anti-viral defenses of airway basal cells.
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Affiliation(s)
- Xiaofang Xu
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Dianhua Qiao
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Allan R. Brasier
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
- Institute for Clinical and Translational Research, University of Wisconsin-Madison, Madison, WI, United States
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2
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Dominguez EC, Roleder C, Ball B, Danilov AV. Cyclin-dependent kinase-9 in B-cell malignancies: pathogenic role and therapeutic implications. Leuk Lymphoma 2023; 64:1893-1904. [PMID: 37552126 DOI: 10.1080/10428194.2023.2244102] [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: 06/02/2023] [Accepted: 07/29/2023] [Indexed: 08/09/2023]
Abstract
Cyclin-dependent kinases (CDK) regulate cell cycle and transcriptional activity. Pan-CDK inhibitors demonstrated early efficacy in lymphoid malignancies, but also have been associated with narrow therapeutic index. Among transcriptional CDKs, CDK7 and CDK9 emerged as promising targets. CDK9 serves as a component of P-TEFb elongation complex and thus is indispensable in mRNA transcription. Selective CDK9 inhibitors demonstrated pre-clinical efficacy in in vitro and in vivo models of B-cell non-Hodgkin lymphoma. CDK9 inhibition results in transcriptional pausing with rapid downmodulation of short-lived oncogenic proteins, e.g. Myc and Mcl-1, followed by cell apoptosis. Early phase clinical trials established safety of CDK9 inhibitors, with manageable neutropenia, infections and gastrointestinal toxicities. In this review, we summarize the rationale of targeting CDK9 in lymphoid malignancies, as well as pre-clinical and early clinical data with pan-CDK and selective CDK9 inhibitors.
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Affiliation(s)
| | - Carly Roleder
- City of Hope National Medical Center, Duarte, CA, USA
| | - Brian Ball
- City of Hope National Medical Center, Duarte, CA, USA
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3
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Okura GC, Bharadwaj AG, Waisman DM. Recent Advances in Molecular and Cellular Functions of S100A10. Biomolecules 2023; 13:1450. [PMID: 37892132 PMCID: PMC10604489 DOI: 10.3390/biom13101450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/21/2023] [Accepted: 09/22/2023] [Indexed: 10/29/2023] Open
Abstract
S100A10 (p11, annexin II light chain, calpactin light chain) is a multifunctional protein with a wide range of physiological activity. S100A10 is unique among the S100 family members of proteins since it does not bind to Ca2+, despite its sequence and structural similarity. This review focuses on studies highlighting the structure, regulation, and binding partners of S100A10. The binding partners of S100A10 were collated and summarized.
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Affiliation(s)
- Gillian C. Okura
- Department of Pathology, Dalhousie University, Halifax, NS B3H 1X5, Canada; (G.C.O.); (A.G.B.)
| | - Alamelu G. Bharadwaj
- Department of Pathology, Dalhousie University, Halifax, NS B3H 1X5, Canada; (G.C.O.); (A.G.B.)
- Departments of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 1X5, Canada
| | - David M. Waisman
- Department of Pathology, Dalhousie University, Halifax, NS B3H 1X5, Canada; (G.C.O.); (A.G.B.)
- Departments of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 1X5, Canada
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4
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Le TK, Cherif C, Omabe K, Paris C, Lannes F, Audebert S, Baudelet E, Hamimed M, Barbolosi D, Finetti P, Bastide C, Fazli L, Gleave M, Bertucci F, Taïeb D, Rocchi P. DDX5 mRNA-targeting antisense oligonucleotide as a new promising therapeutic in combating castration-resistant prostate cancer. Mol Ther 2023; 31:471-486. [PMID: 35965411 PMCID: PMC9931527 DOI: 10.1016/j.ymthe.2022.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 06/26/2022] [Accepted: 08/09/2022] [Indexed: 02/07/2023] Open
Abstract
The heat shock protein 27 (Hsp27) has emerged as a principal factor of the castration-resistant prostate cancer (CRPC) progression. Also, an antisense oligonucleotide (ASO) against Hsp27 (OGX-427 or apatorsen) has been assessed in different clinical trials. Here, we illustrate that Hsp27 highly regulates the expression of the human DEAD-box protein 5 (DDX5), and we define DDX5 as a novel therapeutic target for CRPC treatment. DDX5 overexpression is strongly correlated with aggressive tumor features, notably with CRPC. DDX5 downregulation using a specific ASO-based inhibitor that acts on DDX5 mRNAs inhibits cell proliferation in preclinical models, and it particularly restores the treatment sensitivity of CRPC. Interestingly, through the identification and analysis of DDX5 protein interaction networks, we have identified some specific functions of DDX5 in CRPC that could contribute actively to tumor progression and therapeutic resistance. We first present the interactions of DDX5 and the Ku70/80 heterodimer and the transcription factor IIH, thereby uncovering DDX5 roles in different DNA repair pathways. Collectively, our study highlights critical functions of DDX5 contributing to CRPC progression and provides preclinical proof of concept that a combination of ASO-directed DDX5 inhibition with a DNA damage-inducing therapy can serve as a highly potential novel strategy to treat CRPC.
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Affiliation(s)
- Thi Khanh Le
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France; Department of Life Science, University of Science and Technology of Hanoi, Hanoi 000084, Vietnam
| | - Chaïma Cherif
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France
| | - Kenneth Omabe
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France
| | - Clément Paris
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France
| | - François Lannes
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France; Urology Deparment, AP-HM Hospital Nord, Aix-Marseille University, 13915 Marseille Cedex 20, France
| | - Stéphane Audebert
- Marseille Protéomique, Centre de Recherche en Cancérologie de Marseille, INSERM, CNRS, Institut Paoli-Calmettes, Aix-Marseille University, 13009 Marseille, France
| | - Emilie Baudelet
- Marseille Protéomique, Centre de Recherche en Cancérologie de Marseille, INSERM, CNRS, Institut Paoli-Calmettes, Aix-Marseille University, 13009 Marseille, France
| | - Mourad Hamimed
- Inria - Inserm team COMPO, COMPutational pharmacology and clinical Oncology, Centre Inria Sophia Antipolis - Méditerranée, Centre de Recherches en Cancérologie de Marseille, Inserm U1068, CNRS UMR7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Boulevard Jean Moulin, 13005 Marseille, France
| | - Dominique Barbolosi
- Inria - Inserm team COMPO, COMPutational pharmacology and clinical Oncology, Centre Inria Sophia Antipolis - Méditerranée, Centre de Recherches en Cancérologie de Marseille, Inserm U1068, CNRS UMR7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Boulevard Jean Moulin, 13005 Marseille, France
| | - Pascal Finetti
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France
| | - Cyrille Bastide
- Urology Deparment, AP-HM Hospital Nord, Aix-Marseille University, 13915 Marseille Cedex 20, France
| | - Ladan Fazli
- The Vancouver Prostate Centre, University of British Columbia, Vancouver, BC V6H 3Z6, Canada
| | - Martin Gleave
- The Vancouver Prostate Centre, University of British Columbia, Vancouver, BC V6H 3Z6, Canada
| | - François Bertucci
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France
| | - David Taïeb
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France; La Timone University Hospital, Aix-Marseille University, 13005 Marseille, France; European Center for Research in Medical Imaging, Aix-Marseille University, 13005 Marseille, France
| | - Palma Rocchi
- Predictive Oncology Laboratory, Centre de Recherche en Cancérologie de Marseille, Inserm UMR 1068, CNRS UMR 7258, Institut Paoli-Calmettes, Aix-Marseille University, 27 Bd. Leï Roure, 13273 Marseille, France; European Center for Research in Medical Imaging, Aix-Marseille University, 13005 Marseille, France.
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5
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Ling X, Wu W, Aljahdali IAM, Liao J, Santha S, Fountzilas C, Boland PM, Li F. FL118, acting as a 'molecular glue degrader', binds to dephosphorylates and degrades the oncoprotein DDX5 (p68) to control c-Myc, survivin and mutant Kras against colorectal and pancreatic cancer with high efficacy. Clin Transl Med 2022; 12:e881. [PMID: 35604033 PMCID: PMC9126027 DOI: 10.1002/ctm2.881] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 04/26/2022] [Accepted: 05/03/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Pancreatic ductal adenocarcinoma (PDAC), a difficult-to-treat cancer, is expected to become the second-largest cause of cancer-related deaths by 2030, while colorectal cancer (CRC) is the third most common cancer and the third leading cause of cancer deaths. Currently, there is no effective treatment for PDAC patients. The development of novel agents to effectively treat these cancers remains an unmet clinical need. FL118, a novel anticancer small molecule, exhibits high efficacy against cancers; however, the direct biochemical target of FL118 is unknown. METHODS FL118 affinity purification, mass spectrometry, Nanosep centrifugal device and isothermal titration calorimetry were used for identifying and confirming FL118 binding to DDX5/p68 and its binding affinity. Immunoprecipitation (IP), western blots, real-time reverse transcription PCR, gene silencing, overexpression (OE) and knockout (KO) were used for analysing gene/protein function and expression. Chromatin IP was used for analysing protein-DNA interactions. The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromid assay and human PDAC/CRC cell/tumour models were used for determining PDAC/CRC cell/tumour in vitro and in vivo growth. RESULTS We discovered that FL118 strongly binds to dephosphorylates and degrades the DDX5 oncoprotein via the proteasome degradation pathway without decreasing DDX5 mRNA. Silencing and OE of DDX5 indicated that DDX5 is a master regulator for controlling the expression of multiple oncogenic proteins, including survivin, Mcl-1, XIAP, cIAP2, c-Myc and mutant Kras. Genetic manipulation of DDX5 in PDAC cells affects tumour growth. PDAC cells with DDX5 KO are resistant to FL118 treatment. Our human tumour animal model studies further indicated that FL118 exhibits high efficacy to eliminate human PDAC and CRC tumours that have a high expression of DDX5, while FL118 exhibits less effectiveness in PDAC and CRC tumours with low DDX5 expression. CONCLUSION DDX5 is a bona fide FL118 direct target and can act as a biomarker for predicting PDAC and CRC tumour sensitivity to FL118. This would greatly impact FL118 precision medicine for patients with advanced PDAC or advanced CRC in the clinic. FL118 may act as a 'molecular glue degrader' to directly glue DDX5 and ubiquitination regulators together to degrade DDX5.
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Affiliation(s)
- Xiang Ling
- Department of Pharmacology & TherapeuticsRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Canget BioTekpharma LLCBuffaloNew YorkUSA
| | - Wenjie Wu
- Department of Pharmacology & TherapeuticsRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Canget BioTekpharma LLCBuffaloNew YorkUSA
| | - Ieman A. M. Aljahdali
- Department of Pharmacology & TherapeuticsRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Department of Cellular & Molecular BiologyRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
| | | | | | - Christos Fountzilas
- Department of MedicineRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Developmental Therapeutics (DT) ProgramRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
| | - Patrick M. Boland
- Department of MedicineRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Present address:
Development of Medical Oncology, Rutgers Cancer Institute of New Jersey, The State University of New Jersey, New Brunswick, NJ 08903, USA
| | - Fengzhi Li
- Department of Pharmacology & TherapeuticsRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Developmental Therapeutics (DT) ProgramRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
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6
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Atindaana E, Kissi-Twum A, Emery S, Burnett C, Pitcher J, Visser M, Kidd JM, Telesnitsky A. Bimodal Expression Patterns, and Not Viral Burst Sizes, Predict the Effects of Vpr on HIV-1 Proviral Populations in Jurkat Cells. mBio 2022; 13:e0374821. [PMID: 35384697 PMCID: PMC9040753 DOI: 10.1128/mbio.03748-21] [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] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/28/2022] [Indexed: 11/29/2022] Open
Abstract
Integration site landscapes, clonal dynamics, and latency reversal with or without vpr were compared in HIV-1-infected Jurkat cell populations, and the properties of individual clones were defined. Clones differed in fractions of long terminal repeat (LTR)-active daughter cells, with some clones containing few to no LTR-active cells, while almost all cells were LTR active for others. Clones varied over 4 orders of magnitude in virus release per active cell. Proviruses in largely LTR-active clones were closer to preexisting enhancers and promoters than low-LTR-active clones. Unsurprisingly, major vpr+ clones contained fewer LTR-active cells than vpr- clones, and predominant vpr+ proviruses were farther from enhancers and promoters than those in vpr- pools. Distances to these marks among intact proviruses previously reported for antiretroviral therapy (ART)-suppressed patients revealed that patient integration sites were more similar to those in the vpr+ pool than to vpr- integrants. Complementing vpr-defective proviruses with vpr led to the rapid loss of highly LTR-active clones, indicating that the effect of Vpr on proviral populations occurred after integration. However, major clones in the complemented pool and its vpr- parent population did not differ in burst sizes. When the latency reactivation agents prostratin and JQ1 were applied separately or in combination, vpr+ and vpr- population-wide trends were similar, with dual-treatment enhancement being due in part to reactivated clones that did not respond to either drug applied separately. However, the expression signatures of individual clones differed between populations. These observations highlight how Vpr, exerting selective pressure on proviral epigenetic variation, can shape integration site landscapes, proviral expression patterns, and reactivation properties. IMPORTANCE A bedrock assumption in HIV-1 population modeling is that all active cells release the same amount of virus. However, the findings here revealed that when HIV-infected cells expand into clones, each clone differs in virus production. Reasoning that this variation in expression patterns constituted a population of clones from which differing subsets would prevail under differing environmental conditions, the cytotoxic HIV-1 protein Vpr was introduced, and population dynamics and expression properties were compared in the presence and absence of Vpr. The results showed that whereas most clones produced fairly continuous levels of virus in the absence of Vpr, its presence selected for a distinct subset of clones with properties reminiscent of persistent populations in patients, suggesting the possibility that the interclonal variation in expression patterns observed in culture may contribute to proviral persistence in vivo.
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Affiliation(s)
- Edmond Atindaana
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Abena Kissi-Twum
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon, Greater Accra Region, Ghana
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Greater Accra Region, Ghana
| | - Sarah Emery
- Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Cleo Burnett
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jake Pitcher
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Myra Visser
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jeffrey M. Kidd
- Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Alice Telesnitsky
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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7
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Xu X, Mann M, Qiao D, Li Y, Zhou J, Brasier AR. Bromodomain Containing Protein 4 (BRD4) Regulates Expression of its Interacting Coactivators in the Innate Response to Respiratory Syncytial Virus. Front Mol Biosci 2021; 8:728661. [PMID: 34765643 PMCID: PMC8577543 DOI: 10.3389/fmolb.2021.728661] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 09/24/2021] [Indexed: 12/12/2022] Open
Abstract
Bromodomain-containing protein 4 plays a central role in coordinating the complex epigenetic component of the innate immune response. Previous studies implicated BRD4 as a component of a chromatin-modifying complex that is dynamically recruited to a network of protective cytokines by binding activated transcription factors, polymerases, and histones to trigger their rapid expression via transcriptional elongation. Our previous study extended our understanding of the airway epithelial BRD4 interactome by identifying over 100 functionally important coactivators and transcription factors, whose association is induced by respiratory syncytial virus (RSV) infection. RSV is an etiological agent of recurrent respiratory tract infections associated with exacerbations of chronic obstructive pulmonary disease. Using a highly selective small-molecule BRD4 inhibitor (ZL0454) developed by us, we extend these findings to identify the gene regulatory network dependent on BRD4 bromodomain (BD) interactions. Human small airway epithelial cells were infected in the absence or presence of ZL0454, and gene expression profiling was performed. A highly reproducible dataset was obtained which indicated that BRD4 mediates both activation and repression of RSV-inducible gene regulatory networks controlling cytokine expression, interferon (IFN) production, and extracellular matrix remodeling. Index genes of functionally significant clusters were validated independently. We discover that BRD4 regulates the expression of its own gene during the innate immune response. Interestingly, BRD4 activates the expression of NFκB/RelA, a coactivator that binds to BRD4 in a BD-dependent manner. We extend this finding to show that BRD4 also regulates other components of its functional interactome, including the Mediator (Med) coactivator complex and the SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin (SMARC) subunits. To provide further insight into mechanisms for BRD4 in RSV expression, we mapped 7,845 RSV-inducible Tn5 transposase peaks onto the BRD4-dependent gene bodies. These were located in promoters and introns of cytostructural and extracellular matrix (ECM) formation genes. These data indicate that BRD4 mediates the dynamic response of airway epithelial cells to RNA infection by modulating the expression of its coactivators, controlling the expression of host defense mechanisms and remodeling genes through changes in promoter accessibility.
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Affiliation(s)
- Xiaofang Xu
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Morgan Mann
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Dianhua Qiao
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Yi Li
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Jia Zhou
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Allan R Brasier
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States.,Institute for Clinical and Translational Research (ICTR), University of Wisconsin-Madison, Madison, WI, United States
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8
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Martin EMMA, Enriquez A, Sparrow DB, Humphreys DT, McInerney-Leo AM, Leo PJ, Duncan EL, Iyer KR, Greasby JA, Ip E, Giannoulatou E, Sheng D, Wohler E, Dimartino C, Amiel J, Capri Y, Lehalle D, Mory A, Wilnai Y, Lebenthal Y, Gharavi AG, Krzemień GG, Miklaszewska M, Steiner RD, Raggio C, Blank R, Baris Feldman H, Milo Rasouly H, Sobreira NLM, Jobling R, Gordon CT, Giampietro PF, Dunwoodie SL, Chapman G. Heterozygous loss of WBP11 function causes multiple congenital defects in humans and mice. Hum Mol Genet 2021; 29:3662-3678. [PMID: 33276377 DOI: 10.1093/hmg/ddaa258] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 11/09/2020] [Accepted: 11/25/2020] [Indexed: 12/31/2022] Open
Abstract
The genetic causes of multiple congenital anomalies are incompletely understood. Here, we report novel heterozygous predicted loss-of-function (LoF) and predicted damaging missense variants in the WW domain binding protein 11 (WBP11) gene in seven unrelated families with a variety of overlapping congenital malformations, including cardiac, vertebral, tracheo-esophageal, renal and limb defects. WBP11 encodes a component of the spliceosome with the ability to activate pre-messenger RNA splicing. We generated a Wbp11 null allele in mouse using CRISPR-Cas9 targeting. Wbp11 homozygous null embryos die prior to E8.5, indicating that Wbp11 is essential for development. Fewer Wbp11 heterozygous null mice are found than expected due to embryonic and postnatal death. Importantly, Wbp11 heterozygous null mice are small and exhibit defects in axial skeleton, kidneys and esophagus, similar to the affected individuals, supporting the role of WBP11 haploinsufficiency in the development of congenital malformations in humans. LoF WBP11 variants should be considered as a possible cause of VACTERL association as well as isolated Klippel-Feil syndrome, renal agenesis or esophageal atresia.
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Affiliation(s)
- Ella M M A Martin
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Annabelle Enriquez
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia.,Faculty of Medicine, UNSW, Sydney 2052, Australia
| | - Duncan B Sparrow
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia.,Faculty of Science, UNSW, Sydney 2052, Australia.,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - David T Humphreys
- Faculty of Medicine, UNSW, Sydney 2052, Australia.,Molecular, Structural and Computational Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Aideen M McInerney-Leo
- Dermatology Research Centre, The University of Queensland Diamantina Institute, Translational Research Institute, Brisbane 4072, Australia
| | - Paul J Leo
- Translational Genomics Group, Institute of Health and Biomedical Innovation, Queensland University of Technology, Translational Research Institute, Princess Alexandra Hospital, Woolloongabba 4102, Australia
| | - Emma L Duncan
- Translational Genomics Group, Institute of Health and Biomedical Innovation, Queensland University of Technology, Translational Research Institute, Princess Alexandra Hospital, Woolloongabba 4102, Australia.,Department of Twin Research & Genetic Epidemiology, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King's College London, London SE1 7EH, UK.,Faculty of Medicine, University of Queensland, Herston 4006, Australia
| | - Kavitha R Iyer
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Joelene A Greasby
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Eddie Ip
- Faculty of Medicine, UNSW, Sydney 2052, Australia.,Computational Genomics Laboratory, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Eleni Giannoulatou
- Faculty of Medicine, UNSW, Sydney 2052, Australia.,Computational Genomics Laboratory, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Delicia Sheng
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Elizabeth Wohler
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University, Baltimore 21287, USA
| | - Clémantine Dimartino
- Laboratory of Embryology and Genetics of Human Malformations, Institute National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine, Paris 75015, France.,Paris Descartes-Sorbonne Paris Cité Université, Institut Imagine, Paris 75015, France
| | - Jeanne Amiel
- Laboratory of Embryology and Genetics of Human Malformations, Institute National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine, Paris 75015, France.,Paris Descartes-Sorbonne Paris Cité Université, Institut Imagine, Paris 75015, France.,Département de Génétique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris 75015, France
| | - Yline Capri
- Département de Génétique, Hôpital Robert Debré, Assistance Publique Hôpitaux de Paris, Paris 75019, France
| | - Daphné Lehalle
- Centre Hospitalier Intercommunal Créteil, Créteil 94000, France
| | - Adi Mory
- The Genetics Institute, Tel Aviv Sourasky Medical Center, Tel Aviv 6423906, Israel
| | - Yael Wilnai
- The Genetics Institute, Tel Aviv Sourasky Medical Center, Tel Aviv 6423906, Israel
| | - Yael Lebenthal
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel.,Dana-Dwek Children's Hospital, Tel Aviv Sourasky Medical Center, Pediatric Endocrinology and Diabetes Unit, Tel Aviv 6423906, Israel
| | - Ali G Gharavi
- Department of Medicine, Division of Nephrology, Columbia University, New York, NY 10032, USA
| | - Grażyna G Krzemień
- Department of Pediatrics and Nephrology, Warsaw Medical University, Warsaw 02-091, Poland
| | - Monika Miklaszewska
- Department of Pediatric Nephrology and Hypertension, Jagiellonian University Medical College, Kraków 30-663, Poland
| | - Robert D Steiner
- Marshfield Clinic Health System, Marshfield, WI 54449, USA.,University of Wisconsin School of Medicine and Public Health, Madison, WI 53792, USA
| | - Cathy Raggio
- Hospital for Special Surgery, Pediatrics Orthopedic Surgery, New York, NY 10021, USA
| | - Robert Blank
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Hagit Baris Feldman
- The Genetics Institute, Tel Aviv Sourasky Medical Center, Tel Aviv 6423906, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Hila Milo Rasouly
- Department of Medicine, Division of Nephrology, Columbia University, New York, NY 10032, USA
| | - Nara L M Sobreira
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University, Baltimore 21287, USA
| | - Rebekah Jobling
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, ON M5G1X3, Canada
| | - Christopher T Gordon
- Laboratory of Embryology and Genetics of Human Malformations, Institute National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine, Paris 75015, France.,Paris Descartes-Sorbonne Paris Cité Université, Institut Imagine, Paris 75015, France
| | - Philip F Giampietro
- Department of Pediatrics, University of Illinois-Chicago, Chicago, IL 60607, USA
| | - Sally L Dunwoodie
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia.,Faculty of Medicine, UNSW, Sydney 2052, Australia.,Faculty of Science, UNSW, Sydney 2052, Australia
| | - Gavin Chapman
- Development & Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia.,Faculty of Medicine, UNSW, Sydney 2052, Australia
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9
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Qiao D, Skibba M, Xu X, Garofalo RP, Zhao Y, Brasier AR. Paramyxovirus replication induces the hexosamine biosynthetic pathway and mesenchymal transition via the IRE1α-XBP1s arm of the unfolded protein response. Am J Physiol Lung Cell Mol Physiol 2021; 321:L576-L594. [PMID: 34318710 PMCID: PMC8461800 DOI: 10.1152/ajplung.00127.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The paramyxoviridae, respiratory syncytial virus (RSV), and murine respirovirus are enveloped, negative-sense RNA viruses that are the etiological agents of vertebrate lower respiratory tract infections (LRTIs). We observed that RSV infection in human small airway epithelial cells induced accumulation of glycosylated proteins within the endoplasmic reticulum (ER), increased glutamine-fructose-6-phosphate transaminases (GFPT1/2) and accumulation of uridine diphosphate (UDP)-N-acetylglucosamine, indicating activation of the hexosamine biosynthetic pathway (HBP). RSV infection induces rapid formation of spliced X-box binding protein 1 (XBP1s) and processing of activating transcription factor 6 (ATF6). Using pathway selective inhibitors and shRNA silencing, we find that the inositol-requiring enzyme (IRE1α)-XBP1 arm of the unfolded protein response (UPR) is required not only for activation of the HBP, but also for expression of mesenchymal transition (EMT) through the Snail family transcriptional repressor 1 (SNAI1), extracellular matrix (ECM)-remodeling proteins fibronectin (FN1), and matrix metalloproteinase 9 (MMP9). Probing RSV-induced open chromatin domains by ChIP, we find XBP1 binds and recruits RNA polymerase II to the IL6, SNAI1, and MMP9 promoters and the intragenic superenhancer of glutamine-fructose-6-phosphate transaminase 2 (GFPT2). The UPR is sustained through RSV by an autoregulatory loop where XBP1 enhances Pol II binding to its own promoter. Similarly, we investigated the effects of murine respirovirus infection on its natural host (mouse). Murine respirovirus induces mucosal growth factor response, EMT, and the indicators of ECM remodeling in an IRE1α-dependent manner, which persists after viral clearance. These data suggest that IRE1α-XBP1s arm of the UPR pathway is responsible for paramyxovirus-induced metabolic adaptation and mucosal remodeling via EMT and ECM secretion.
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Affiliation(s)
- Dianhua Qiao
- Department of Internal Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
| | - Melissa Skibba
- Department of Internal Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
| | - Xiaofang Xu
- Department of Internal Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
| | - Roberto P Garofalo
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas
| | - Yingxin Zhao
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas
| | - Allan R Brasier
- Department of Internal Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin.,Institute for Clinical and Translational Research, University of Wisconsin-Madison, Madison, Wisconsin
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10
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NFAT5-Mediated Signalling Pathways in Viral Infection and Cardiovascular Dysfunction. Int J Mol Sci 2021; 22:ijms22094872. [PMID: 34064510 PMCID: PMC8124654 DOI: 10.3390/ijms22094872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 04/30/2021] [Accepted: 05/02/2021] [Indexed: 02/06/2023] Open
Abstract
The nuclear factor of activated T cells 5 (NFAT5) is well known for its sensitivity to cellular osmolarity changes, such as in the kidney medulla. Accumulated evidence indicates that NFAT5 is also a sensitive factor to stress signals caused by non-hypertonic stimuli such as heat shock, biomechanical stretch stress, ischaemia, infection, etc. These osmolality-related and -unrelated stimuli can induce NFAT5 upregulation, activation and nuclear accumulation, leading to its protective role against various detrimental effects. However, dysregulation of NFAT5 expression may cause pathological conditions in different tissues, leading to a variety of diseases. These protective or pathogenic effects of NFAT5 are dictated by the regulation of its target gene expression and activation of its signalling pathways. Recent studies have found a number of kinases that participate in the phosphorylation/activation of NFAT5 and related signal proteins. Thus, this review will focus on the NFAT5-mediated signal transduction pathways. As for the stimuli that upregulate NFAT5, in addition to the stresses caused by hyperosmotic and non-hyperosmotic environments, other factors such as miRNA, long non-coding RNA, epigenetic modification and viral infection also play an important role in regulating NFAT5 expression; thus, the discussion in this regard is another focus of this review. As the heart, unlike the kidneys, is not normally exposed to hypertonic environments, studies on NFAT5-mediated cardiovascular diseases are just emerging and rapidly progressing. Therefore, we have also added a review on the progress made in this field of research.
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11
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Bury M, Le Calvé B, Ferbeyre G, Blank V, Lessard F. New Insights into CDK Regulators: Novel Opportunities for Cancer Therapy. Trends Cell Biol 2021; 31:331-344. [PMID: 33676803 DOI: 10.1016/j.tcb.2021.01.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 12/13/2022]
Abstract
Cyclins and their catalytic partners, the cyclin-dependent kinases (CDKs), control the transition between different phases of the cell cycle. CDK/cyclin activity is regulated by CDK inhibitors (CKIs), currently comprising the CDK-interacting protein/kinase inhibitory protein (CIP/KIP) family and the inhibitor of kinase (INK) family. Recent studies have identified a third group of CKIs, called ribosomal protein-inhibiting CDKs (RPICs). RPICs were discovered in the context of cellular senescence, a stable cell cycle arrest with tumor-suppressing abilities. RPICs accumulate in the nonribosomal fraction of senescent cells due to a decrease in rRNA biogenesis. Accordingly, RPICs are often downregulated in human cancers together with other ribosomal proteins, the tumor-suppressor functions of which are still under study. In this review, we discuss unique therapies that have been developed to target CDK activity in the context of cancer treatment or senescence-associated pathologies, providing novel tools for precision medicine.
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Affiliation(s)
- Marina Bury
- De Duve Institute, UCLouvain, 1200 Brussels, Belgium
| | | | - Gerardo Ferbeyre
- Department of Biochemistry and Molecular Medicine, University of Montreal, Montreal, QC, H3C 3J7, Canada.
| | - Volker Blank
- Lady Davis Institute for Medical Research, Departments of Medicine and Physiology, McGill University, Montreal, QC, H3T 1E2, Canada.
| | - Frédéric Lessard
- Department of Biochemistry and Molecular Medicine, University of Montreal, Montreal, QC, H3C 3J7, Canada.
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12
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Alternative mRNA Processing of Innate Response Pathways in Respiratory Syncytial Virus (RSV) Infection. Viruses 2021; 13:v13020218. [PMID: 33572560 PMCID: PMC7912025 DOI: 10.3390/v13020218] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 12/14/2022] Open
Abstract
The innate immune response (IIR) involves rapid genomic expression of protective interferons (IFNs) and inflammatory cytokines triggered by intracellular viral replication. Although the transcriptional control of the innate pathway is known in substantial detail, little is understood about the complexity of alternative splicing (AS) and alternative polyadenylation (APA) of mRNAs underlying the cellular IIR. In this study, we applied single-molecule, real-time (SMRT) sequencing with mRNA quantitation using short-read mRNA sequencing to characterize changes in mRNA processing in the epithelial response to respiratory syncytial virus (RSV) replication. Mock or RSV-infected human small-airway epithelial cells (hSAECs) were profiled using SMRT sequencing and the curated transcriptome analyzed by structural and quality annotation of novel transcript isoforms (SQANTI). We identified 113,082 unique isoforms; 28,561 represented full splice matches, and 45% of genes expressed six or greater AS mRNA isoforms. Identification of differentially expressed AS isoforms was accomplished by mapping a short-read RNA sequencing expression matrix to the curated transcriptome, and 905 transcripts underwent differential polyadenylation site analysis enriched in protein secretion, translation, and mRNA degradation. We focused on 355 genes showing differential isoform utilization (DIU), indicating where a new AS isoform becomes a major fraction of mRNA isoforms expressed. In pathway and network enrichment analyses, we observed that DIU transcripts are substantially enriched in cell cycle control and IIR pathways. Interestingly, the RelA/IRF7 innate regulators showed substantial DIU where major transcripts included distinct isoforms with exon occlusion, intron inclusion, and alternative transcription start site utilization. We validated the presence of RelA and IRF7 AS isoforms as well as their induction by RSV using eight isoform-specific RT-PCR assays. These isoforms were identified in both immortalized and primary small-airway epithelial cells. We concluded that the cell cycle and IIR are differentially spliced in response to RSV. These data indicate that substantial post-transcriptional complexity regulates the antiviral response.
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13
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Brasier AR. RSV Reprograms the CDK9•BRD4 Chromatin Remodeling Complex to Couple Innate Inflammation to Airway Remodeling. Viruses 2020; 12:v12040472. [PMID: 32331282 PMCID: PMC7232410 DOI: 10.3390/v12040472] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/17/2020] [Accepted: 04/19/2020] [Indexed: 02/06/2023] Open
Abstract
Respiratory syncytial virus infection is responsible for seasonal upper and lower respiratory tract infections worldwide, causing substantial morbidity. Self-inoculation of the virus into the nasopharynx results in epithelial replication and distal spread into the lower respiratory tract. Here, respiratory syncytial virus (RSV) activates sentinel cells important in the host inflammatory response, resulting in epithelial-derived cytokine and interferon (IFN) expression resulting in neutrophilia, whose intensity is associated with disease severity. I will synthesize key findings describing how RSV replication activates intracellular NFκB and IRF signaling cascades controlling the innate immune response (IIR). Recent studies have implicated a central role for Scg1a1+ expressing progenitor cells in IIR, a cell type uniquely primed to induce neutrophilic-, T helper 2 (Th2)-polarizing-, and fibrogenic cytokines that play distinct roles in disease pathogenesis. Molecular studies have linked the positive transcriptional elongation factor-b (P-TEFb), a pleiotrophic chromatin remodeling complex in immediate-early IIR gene expression. Through intrinsic kinase activity of cyclin dependent kinase (CDK) 9 and atypical histone acetyl transferase activity of bromodomain containing protein 4 (BRD4), P-TEFb mediates transcriptional elongation of IIR genes. Unbiased proteomic studies show that the CDK9•BRD4 complex is dynamically reconfigured by the innate response and targets TGFβ-dependent fibrogenic gene networks. Chronic activation of CDK9•BRD4 mediates chromatin remodeling fibrogenic gene networks that cause epithelial mesenchymal transition (EMT). Mesenchymal transitioned epithelial cells elaborate TGFβ and IL6 that function in a paracrine manner to expand the population of subepithelial myofibroblasts. These findings may account for the long-term reduction in pulmonary function in children with severe lower respiratory tract infection (LRTI). Modifying chromatin remodeling properties of the CDK9•BRD4 coactivators may provide a mechanism for reducing post-infectious airway remodeling that are a consequence of severe RSV LRTIs.
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Affiliation(s)
- Allan R Brasier
- Institute for Clinical and Translational Research; University of Wisconsin-Madison School of Medicine and Public Health; Madison, WI 53705, USA
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14
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Sithole N, Williams CA, Abbink TEM, Lever AML. DDX5 potentiates HIV-1 transcription as a co-factor of Tat. Retrovirology 2020; 17:6. [PMID: 32228614 PMCID: PMC7106839 DOI: 10.1186/s12977-020-00514-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 03/16/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND HIV-1 does not encode a helicase and hijacks those of the cell for efficient replication. We and others previously showed that the DEAD box helicase, DDX5, is an essential HIV dependency factor. DDX5 was recently shown to be associated with the 7SK snRNP. Cellular positive transcription elongation factor b (P-TEFb) is bound in an inactive form with HEXIM1/2 on 7SK snRNP. The Tat/P-TEFb complex is essential for efficient processivity of Pol II in HIV-1 transcription elongation and Tat competes with HEXIM1/2 for P-TEFb. We investigated the precise role of DDX5 in HIV replication using siRNA mediated knockdown and rescue with DDX5 mutants which prevent protein-protein interactions and RNA and ATP binding. RESULTS We demonstrate a critical role for DDX5 in the Tat/HEXIM1 interaction. DDX5 acts to potentiate Tat activity and can bind both Tat and HEXIM1 suggesting it may facilitate the dissociation of HEXIM1/2 from the 7SK-snRNP complex, enhancing Tat/P-TEFb availability. We show knockdown of DDX5 in a T cell line significantly reduces HIV-1 infectivity and viral protein production. This activity is unique to DDX5 and cannot be substituted by its close paralog DDX17. Overexpression of DDX5 stimulates the Tat/LTR promoter but suppresses other cellular and viral promoters. Individual mutations of conserved ATP binding, RNA binding, helicase related or protein binding motifs within DDX5 show that the N terminal RNA binding motifs, the Walker B and the glycine doublet motifs are essential for this function. The Walker A and RNA binding motifs situated on the transactivation domain are however dispensable. CONCLUSION DDX5 is an essential cellular factor for efficient HIV transcription elongation. It interacts with Tat and may potentiate the availability of P-TEFb through sequestering HEXIM1.
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Affiliation(s)
- Nyaradzai Sithole
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Claire A Williams
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
- Department of Microbiology, Specialist Virology Centre, Norfolk and Norwich University Hospitals, Norwich, UK
| | - Truus E M Abbink
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
- Department of Paediatrics, Child Neurology, Centre for Childhood White Matter Disorders, VU University Medical Centre, Amsterdam, The Netherlands
| | - Andrew M L Lever
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK.
- Department of Medicine, National University of Singapore, Singapore, 119228, Singapore.
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15
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Decker TM, Forné I, Straub T, Elsaman H, Ma G, Shah N, Imhof A, Eick D. Analog-sensitive cell line identifies cellular substrates of CDK9. Oncotarget 2019; 10:6934-6943. [PMID: 31857848 PMCID: PMC6916755 DOI: 10.18632/oncotarget.27334] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 11/07/2019] [Indexed: 11/25/2022] Open
Abstract
Transcriptional cyclin-dependent kinases regulate all phases of transcription. Cyclin-dependent kinase 9 (CDK9) has been implicated in the regulation of promoter-proximal pausing of RNA polymerase II and more recently in transcription termination. Study of the substrates of CDK9 has mostly been limited to in vitro approaches that lack a quantitative assessment of CDK9 activity. Here we analyzed the cellular phosphoproteome upon inhibition of CDK9 by combining analog-sensitive kinase technology with quantitative phosphoproteomics in Raji B-cells. Our analysis revealed the activity of CDK9 on 1102 phosphosites quantitatively, and we identified 120 potential cellular substrates. Furthermore, a substantial number of CDK9 substrates were described as splicing factors, highlighting the role of CDK9 in transcription-coupled splicing events. Based on comparison to in vitro data, our findings suggest that cellular context fundamentally impacts the activity of CDK9 and specific selection of its substrates.
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Affiliation(s)
- Tim-Michael Decker
- Department of Molecular Epigenetics, Helmholtz Center Munich and Center for Integrated Protein Science Munich (CIPSM), Germany.,Present address: Department of Biochemistry, University of Colorado, Boulder, USA
| | - Ignasi Forné
- Biomedical Center Munich, ZFP, Ludwig-Maximilian University Munich, Germany
| | - Tobias Straub
- Bioinformatic Unit, Biomedical Center Munich, Ludwig-Maximilian University Munich, Planegg-Martinsried, Germany
| | - Hesham Elsaman
- Department of Molecular Epigenetics, Helmholtz Center Munich and Center for Integrated Protein Science Munich (CIPSM), Germany
| | - Guoli Ma
- Department of Molecular Epigenetics, Helmholtz Center Munich and Center for Integrated Protein Science Munich (CIPSM), Germany
| | - Nilay Shah
- Department of Molecular Epigenetics, Helmholtz Center Munich and Center for Integrated Protein Science Munich (CIPSM), Germany.,Present address: Stowers Institute for Medical Research, Kansas City, Missouri, USA
| | - Axel Imhof
- Biomedical Center Munich, ZFP, Ludwig-Maximilian University Munich, Germany
| | - Dirk Eick
- Department of Molecular Epigenetics, Helmholtz Center Munich and Center for Integrated Protein Science Munich (CIPSM), Germany
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16
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Validation of the epigenetic reader bromodomain-containing protein 4 (BRD4) as a therapeutic target for treatment of airway remodeling. Drug Discov Today 2019; 25:126-132. [PMID: 31733396 DOI: 10.1016/j.drudis.2019.11.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/02/2019] [Accepted: 11/06/2019] [Indexed: 12/25/2022]
Abstract
Structural remodeling is central to the initiation and progression of many chronic lung diseases, representing an important unmet need. We examine the evidence supporting bromodomain-containing protein 4 (BRD4) as a validated biological target for treatment of airway remodeling. In epithelial cells and fibroblasts, BRD4 serves as a scaffold for chromatin remodeling complexes in active super-enhancers. In response to inflammatory stimuli, BRD4 is repositioned to innate and mesenchymal genes activating their production. Proof-of-concept studies show promising benefit of selective BRD4 inhibitors in disrupting epithelial mesenchymal transition and myofibroblast transition in diverse models of lung injury. Recent identification of biomarkers of BRD4 provides a basis for further drug development for application in viral-induced airway inflammation, COPD and interstitial lung diseases.
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17
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Brasier AR, Boldogh I. Targeting inducible epigenetic reprogramming pathways in chronic airway remodeling. Drugs Context 2019; 8:dic-2019-8-3. [PMID: 31692901 PMCID: PMC6821469 DOI: 10.7573/dic.2019-8-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 09/16/2019] [Accepted: 09/19/2019] [Indexed: 02/08/2023] Open
Abstract
Allergic asthma is a chronic inflammatory airway disease whose clinical course is punctuated by acute exacerbations from aeroallergen exposure or respiratory virus infections. Aeroallergens and respiratory viruses stimulate toll-like receptor (TLR) signaling, producing oxidative injury and inflammation. Repetitive exacerbations produce complex mucosal adaptations, cell-state changes, and structural remodeling. These structural changes produce substantial morbidity, decrease lung capacity, and impair quality of life. We will review recent systems-level studies that provide fundamental new insights into how repetitive activation of innate signaling pathways produce epigenetic ‘training’ to induce adaptive epithelial responses. Oxidative stress produced downstream of TLR signaling induces transient oxidation of guanine bases in the regulatory regions of inflammatory genes. The epigenetic mark 8-oxoG is bound by a pleiotropic DNA repair enzyme, 8-oxoguanine DNA glycosylase (OGG1), which induces conformational changes in adjacent DNA to recruit the NFκB·bromodomain-containing protein 4 (BRD4) complex. The NFκB·BRD4 complex not only plays a central role in inflammation, but also triggers mesenchymal transition and extracellular matrix remodeling. Small molecule inhibitors of OGG1-8-oxoG binding and BRD4–acetylated histone interaction have been developed. We present studies demonstrating efficacy of these in reducing airway inflammation in preclinical models. Targeting inducible epigenetic reprogramming pathway shows promise for therapeutics in reversing airway remodeling in a variety of chronic airway diseases.
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Affiliation(s)
- Allan R Brasier
- Institute for Clinical and Translational Research, University of Wisconsin-Madison School of Medicine and Public Health, 4246 Health Sciences Learning Center, 750 Highland Ave, Madison, WI 53705, USA
| | - Istvan Boldogh
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, 301 University Blvd, Galveston, TX 77555, USA
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18
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Takeuchi A, Iida K, Tsubota T, Hosokawa M, Denawa M, Brown JB, Ninomiya K, Ito M, Kimura H, Abe T, Kiyonari H, Ohno K, Hagiwara M. Loss of Sfpq Causes Long-Gene Transcriptopathy in the Brain. Cell Rep 2019; 23:1326-1341. [PMID: 29719248 DOI: 10.1016/j.celrep.2018.03.141] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/19/2018] [Accepted: 03/30/2018] [Indexed: 12/13/2022] Open
Abstract
Genes specifically expressed in neurons contain members with extended long introns. Longer genes present a problem with respect to fulfilment of gene length transcription, and evidence suggests that dysregulation of long genes is a mechanism underlying neurodegenerative and psychiatric disorders. Here, we report the discovery that RNA-binding protein Sfpq is a critical factor for maintaining transcriptional elongation of long genes. We demonstrate that Sfpq co-transcriptionally binds to long introns and is required for sustaining long-gene transcription by RNA polymerase II through mediating the interaction of cyclin-dependent kinase 9 with the elongation complex. Phenotypically, Sfpq disruption caused neuronal apoptosis in developing mouse brains. Expression analysis of Sfpq-regulated genes revealed specific downregulation of developmentally essential neuronal genes longer than 100 kb in Sfpq-disrupted brains; those genes are enriched in associations with neurodegenerative and psychiatric diseases. The identified molecular machinery yields directions for targeted investigations of the association between long-gene transcriptopathy and neuronal diseases.
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Affiliation(s)
- Akihide Takeuchi
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Kei Iida
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan; Medical Research Support Center, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Toshiaki Tsubota
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Motoyasu Hosokawa
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Masatsugu Denawa
- Medical Research Support Center, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - J B Brown
- Laboratory for Molecular Biosciences, Life Science Informatics Research Unit, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kensuke Ninomiya
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Mikako Ito
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Hiroshi Kimura
- Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan
| | - Takaya Abe
- Genetic Engineering Team, RIKEN Center for Life Science Technologies, Kobe 650-0047, Japan
| | - Hiroshi Kiyonari
- Genetic Engineering Team, RIKEN Center for Life Science Technologies, Kobe 650-0047, Japan; Animal Resource Development Unit, R IKEN Center for Life Science Technologies, Kobe 650-0047, Japan
| | - Kinji Ohno
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Masatoshi Hagiwara
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
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19
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Huan W, Zhang J, Li Y, Zhi K. Involvement of DHX9/YB-1 complex induced alternative splicing of Krüppel-like factor 5 mRNA in phenotypic transformation of vascular smooth muscle cells. Am J Physiol Cell Physiol 2019; 317:C262-C269. [PMID: 31116584 DOI: 10.1152/ajpcell.00067.2019] [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] [Indexed: 01/19/2023]
Abstract
Phenotypic transformation of vascular smooth muscle cells is a key phenomenon in the development of aortic dissection disease. However, the molecular mechanisms underlying this phenomenon have not been fully understood. We used β-BAPN combined with ANG II treatment to establish a disease model of acute aortic dissection (AAD) in mice. We first examined the gene expression profile of aortic tissue in mice with AAD using a gene chip, followed by confirmation of DExH-box helicase 9 (DHX9) expression using RT-PCR, Western blot, and immunofluorescence analysis. We further developed vascular smooth muscle cell-specific DHX9 conditional knockout mice and conducted differential and functional analysis of gene expression and alternative splicing in mouse vascular smooth muscle cells. Finally, we examined the involvement of DHX9 in Krüppel-like factor 5 (KLF5) mRNA alternative splicing. Our study reported a significant decrease in the expression of DHX9 in the vascular smooth muscle cells (VSMCs) of mice with AAD. The smooth muscle cell-specific knockout of DHX9 exacerbated the development of AAD and altered the transcriptional level expression of many smooth muscle cell phenotype-related genes. Finally, we reported that DHX9 may induce alternative splicing of KLF5 mRNA by bridging YB-1. These results together suggested a new pathogenic mechanism underlying the development of AAD, and future research of this mechanism may help identify effective therapeutic intervention for AAD.
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Affiliation(s)
- Wei Huan
- Department of Vascular Surgery, Changzheng Hospital, The Second Military Medical University, Shanghai, China
| | - Jing Zhang
- Department of Cardiovascular Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Yingke Li
- Department of Anesthesiology, Changzheng Hospital, The Second Military Medical University, Shanghai, China
| | - Kangkang Zhi
- Department of Vascular Surgery, Changzheng Hospital, The Second Military Medical University, Shanghai, China
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20
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Zhang Y, Sun H, Zhang J, Brasier AR, Zhao Y. Quantitative Assessment of the Effects of Trypsin Digestion Methods on Affinity Purification-Mass Spectrometry-based Protein-Protein Interaction Analysis. J Proteome Res 2017; 16:3068-3082. [PMID: 28726418 DOI: 10.1021/acs.jproteome.7b00432] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Affinity purification-mass spectrometry (AP-MS) has become the method of choice for discovering protein-protein interactions (PPIs) under native conditions. The success of AP-MS depends on the efficiency of trypsin digestion and the recovery of the tryptic peptides for MS analysis. Several different protocols have been used for trypsin digestion of protein complexes in AP-MS studies, but no systematic studies have been conducted on the impact of trypsin digestion conditions on the identification of PPIs. Here, we used NFκB/RelA and Bromodomain-containing protein 4 (BRD4) as baits and test five distinct trypsin digestion methods (two using "on-beads," three using "elution-digestion" protocols). Although the performance of the trypsin digestion protocols change slightly depending on the different baits, antibodies and cell lines used, we found that elution-digestion methods consistently outperformed on-beads digestion methods. The high-abundance interactors can be identified universally by all five methods, but the identification of low-abundance RelA interactors is significantly affected by the choice of trypsin digestion method. We also found that different digestion protocols influence the selected reaction monitoring (SRM)-MS quantification of PPIs, suggesting that optimization of trypsin digestion conditions may be required for robust targeted analysis of PPIs.
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Affiliation(s)
- Yueqing Zhang
- Department of Internal Medicine, University of Texas Medical Branch (UTMB) , Galveston, Texas 77555, United States
| | - Hong Sun
- Department of Internal Medicine, University of Texas Medical Branch (UTMB) , Galveston, Texas 77555, United States
| | - Jing Zhang
- Department of Internal Medicine, University of Texas Medical Branch (UTMB) , Galveston, Texas 77555, United States
| | - Allan R Brasier
- Department of Internal Medicine, University of Texas Medical Branch (UTMB) , Galveston, Texas 77555, United States.,Institute for Translational Sciences, UTMB , Galveston, Texas 77555, United States.,Sealy Center for Molecular Medicine, UTMB , Galveston, Texas 77555, United States
| | - Yingxin Zhao
- Department of Internal Medicine, University of Texas Medical Branch (UTMB) , Galveston, Texas 77555, United States.,Institute for Translational Sciences, UTMB , Galveston, Texas 77555, United States.,Sealy Center for Molecular Medicine, UTMB , Galveston, Texas 77555, United States
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21
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Epigenetic silencing of IRF1 dysregulates type III interferon responses to respiratory virus infection in epithelial to mesenchymal transition. Nat Microbiol 2017; 2:17086. [PMID: 28581456 PMCID: PMC5501188 DOI: 10.1038/nmicrobiol.2017.86] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 04/25/2017] [Indexed: 12/11/2022]
Abstract
Chronic oxidative injury produced by airway disease triggers TGFβ-mediated epigenetic reprogramming known as the epithelial-mesenchymal transition (EMT). We observe that EMT silences protective mucosal interferon (IFN)-I/-III production associated with enhanced rhinovirus (RV) and respiratory syncytial virus(RSV) replication. Mesenchymal transitioned cells are defective in inducible interferon regulatory factor (IRF)1 expression by occluding RelA and IRF3 access to the promoter. IRF1 is necessary for expression of type III IFNs (IFNLs-1 and 2/3). Induced by the EMT, Zinc Finger E-Box Binding Homeobox 1 (ZEB1) binds and silences IRF1. Ectopic ZEB1 is sufficient for IRF1 silencing, whereas ZEB1 knockdown partially restores IRF1-IFNL upregulation. ZEB1 silences IRF1 through the catalytic activity of the Enhancer of Zeste 2 Polycomb Repressive Complex 2 Subunit (EZH2), forming repressive H3K27(me3) marks. We observe that IRF1 expression is mediated by ZEB1 de-repression; our study demonstrates how airway remodeling/fibrosis is associated with a defective mucosal antiviral response through ZEB1-initiated epigenetic silencing.
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22
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Abstract
Over the past two decades there has been a great deal of interest in the development of inhibitors of the cyclin-dependent kinases (CDKs). This attention initially stemmed from observations that different CDK isoforms have key roles in cancer cell proliferation through loss of regulation of the cell cycle, a hallmark feature of cancer. CDKs have now been shown to regulate other processes, particularly various aspects of transcription. The early non-selective CDK inhibitors exhibited considerable toxicity and proved to be insufficiently active in most cancers. The lack of patient selection biomarkers and an absence of understanding of the inhibitory profile required for efficacy hampered the development of these inhibitors. However, the advent of potent isoform-selective inhibitors with accompanying biomarkers has re-ignited interest. Palbociclib, a selective CDK4/6 inhibitor, is now approved for the treatment of ER+/HER2- advanced breast cancer. Current developments in the field include the identification of potent and selective inhibitors of the transcriptional CDKs; these include tool compounds that have allowed exploration of individual CDKs as cancer targets and the determination of their potential therapeutic windows. Biomarkers that allow the selection of patients likely to respond are now being discovered. Drug resistance has emerged as a major hurdle in the clinic for most protein kinase inhibitors and resistance mechanism are beginning to be identified for CDK inhibitors. This suggests that the selective inhibitors may be best used combined with standard of care or other molecularly targeted agents now in development rather than in isolation as monotherapies.
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Affiliation(s)
- Steven R Whittaker
- Division of Cancer Therapeutics, The Institute of Cancer Research, London SW7 3RP, United Kingdom
| | - Aurélie Mallinger
- Division of Cancer Therapeutics, The Institute of Cancer Research, London SW7 3RP, United Kingdom; Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London SW7 3RP, United Kingdom
| | - Paul Workman
- Division of Cancer Therapeutics, The Institute of Cancer Research, London SW7 3RP, United Kingdom; Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London SW7 3RP, United Kingdom
| | - Paul A Clarke
- Division of Cancer Therapeutics, The Institute of Cancer Research, London SW7 3RP, United Kingdom; Cancer Research UK Cancer Therapeutics Unit, The Institute of Cancer Research, London SW7 3RP, United Kingdom.
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23
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Tian B, Yang J, Zhao Y, Ivanciuc T, Sun H, Garofalo RP, Brasier AR. BRD4 Couples NF-κB/RelA with Airway Inflammation and the IRF-RIG-I Amplification Loop in Respiratory Syncytial Virus Infection. J Virol 2017; 91:e00007-17. [PMID: 28077651 PMCID: PMC5331805 DOI: 10.1128/jvi.00007-17] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 01/09/2023] Open
Abstract
The airway mucosa expresses protective interferon (IFN) and inflammatory cytokines in response to respiratory syncytial virus (RSV) infection. In this study, we examine the role of bromodomain containing 4 (BRD4) in mediating this innate immune response in human small airway epithelial cells. We observe that RSV induces BRD4 to complex with NF-κB/RelA. BRD4 is functionally required for expression of the NF-κB-dependent inflammatory gene regulatory network (GRN), including the IFN response factor 1 (IRF1) and IRF7, which mediate a cross talk pathway for RIG-I upregulation. Mechanistically, BRD4 is required for cyclin-dependent kinase 9 (CDK9) recruitment and phospho-Ser 2 carboxy-terminal domain (CTD) RNA polymerase (Pol) II formation on the promoters of IRF1, IRF7, and RIG-I, producing their enhanced expression by transcriptional elongation. We also find that BRD4 independently regulates CDK9/phospho-Ser 2 CTD RNA Pol II recruitment to the IRF3-dependent IFN-stimulated genes (ISGs). In vivo, poly(I·C)-induced neutrophilia and mucosal chemokine production are blocked by a small-molecule BRD4 bromodomain inhibitor. Similarly, BRD4 inhibition reduces RSV-induced neutrophilia, mucosal CXC chemokine expression, activation of the IRF7-RIG-I autoamplification loop, mucosal IFN expression, and airway obstruction. RSV infection activates BRD4 acetyltransferase activity on histone H3 Lys (K) 122, demonstrating that RSV infection activates BRD4 in vivo These data validate BRD4 as a major effector of RSV-induced inflammation and disease. BRD4 is required for coupling NF-κB to expression of inflammatory genes and the IRF-RIG-I autoamplification pathway and independently facilitates antiviral ISG expression. BRD4 inhibition may be a strategy to reduce exuberant virus-induced mucosal airway inflammation.IMPORTANCE In the United States, 2.1 million children annually require medical attention for RSV infections. A first line of defense is the expression of the innate gene network by infected epithelial cells. Expression of the innate response requires the recruitment of transcriptional elongation factors to rapidly induce innate response genes through an unknown mechanism. We discovered that RSV infection induces a complex of bromodomain containing 4 (BRD4) with NF-κB and cyclin-dependent kinase 9 (CDK9). BRD4 is required for stable CDK9 binding, phospho-Ser 2 RNA Pol II formation, and histone acetyltransferase activity. Inhibition of BRD4 blocks Toll-like receptor 3 (TLR3)-dependent neutrophilia and RSV-induced inflammation, demonstrating its importance in the mucosal innate response in vivo Our study shows that BRD4 plays a central role in inflammation and activation of the IRF7-RIG-I amplification loop vital for mucosal interferon expression. BRD4 inhibition may be a strategy for modulating exuberant mucosal airway inflammation.
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Affiliation(s)
- Bing Tian
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
- Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas, USA
| | - Jun Yang
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
- Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas, USA
| | - Yingxin Zhao
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
- Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas, USA
- Institute for Translational Sciences, University of Texas Medical Branch, Galveston, Texas, USA
| | - Teodora Ivanciuc
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas, USA
| | - Hong Sun
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
| | - Roberto P Garofalo
- Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas, USA
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas, USA
| | - Allan R Brasier
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
- Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas, USA
- Institute for Translational Sciences, University of Texas Medical Branch, Galveston, Texas, USA
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24
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Targeting Chromatin Remodeling in Inflammation and Fibrosis. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2016; 107:1-36. [PMID: 28215221 DOI: 10.1016/bs.apcsb.2016.11.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Mucosal surfaces of the human body are lined by a contiguous epithelial cell surface that forms a barrier to aerosolized pathogens. Specialized pattern recognition receptors detect the presence of viral pathogens and initiate protective host responses by triggering activation of the nuclear factor κB (NFκB)/RelA transcription factor and formation of a complex with the positive transcription elongation factor (P-TEFb)/cyclin-dependent kinase (CDK)9 and Bromodomain-containing protein 4 (BRD4) epigenetic reader. The RelA·BRD4·P-TEFb complex produces acute inflammation by regulating transcriptional elongation, which produces a rapid genomic response by inactive genes maintained in an open chromatin configuration engaged with hypophosphorylated RNA polymerase II. We describe recent studies that have linked prolonged activation of the RelA-BRD4 pathway with the epithelial-mesenchymal transition (EMT) by inducing a core of EMT corepressors, stimulating secretion of growth factors promoting airway fibrosis. The mesenchymal state produces rewiring of the kinome and reprogramming of innate responses toward inflammation. In addition, the core regulator Zinc finger E-box homeodomain 1 (ZEB1) silences the expression of the interferon response factor 1 (IRF1), required for type III IFN expression. This epigenetic silencing is mediated by the Enhancer of Zeste 2 (EZH2) histone methyltransferase. Because of their potential applications in cancer and inflammation, small-molecule inhibitors of NFκB/RelA, CDK9, BRD4, and EZH2 have been the targets of medicinal chemistry efforts. We suggest that disruption of the RelA·BRD4·P-TEFb pathway and EZH2 methyltransferase has important implications for reversing fibrosis and restoring normal mucosal immunity in chronic inflammatory diseases.
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25
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Sonawane YA, Taylor MA, Napoleon JV, Rana S, Contreras JI, Natarajan A. Cyclin Dependent Kinase 9 Inhibitors for Cancer Therapy. J Med Chem 2016; 59:8667-8684. [PMID: 27171036 PMCID: PMC5636177 DOI: 10.1021/acs.jmedchem.6b00150] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
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Cyclin dependent kinase (CDK) inhibitors
have been the topic of intense research for nearly 2 decades due to
their widely varied and critical functions within the cell. Recently
CDK9 has emerged as a druggable target for the development of cancer
therapeutics. CDK9 plays a crucial role in transcription regulation;
specifically, CDK9 mediated transcriptional regulation of short-lived
antiapoptotic proteins is critical for the survival of transformed
cells. Focused chemical libraries based on a plethora of scaffolds
have resulted in mixed success with regard to the development of selective
CDK9 inhibitors. Here we review the regulation of CDK9, its cellular
functions, and common core structures used to target CDK9, along with
their selectivity profile and efficacy in vitro and in vivo.
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Affiliation(s)
- Yogesh A Sonawane
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center , Omaha, Nebraska 68198-6805, United States
| | - Margaret A Taylor
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center , Omaha, Nebraska 68198-6805, United States
| | - John Victor Napoleon
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center , Omaha, Nebraska 68198-6805, United States
| | - Sandeep Rana
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center , Omaha, Nebraska 68198-6805, United States
| | - Jacob I Contreras
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center , Omaha, Nebraska 68198-6805, United States
| | - Amarnath Natarajan
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center , Omaha, Nebraska 68198-6805, United States
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26
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Emerson JM, Bartholomai BM, Ringelberg CS, Baker SE, Loros JJ, Dunlap JC. period-1 encodes an ATP-dependent RNA helicase that influences nutritional compensation of the Neurospora circadian clock. Proc Natl Acad Sci U S A 2015; 112:15707-12. [PMID: 26647184 PMCID: PMC4697410 DOI: 10.1073/pnas.1521918112] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mutants in the period-1 (prd-1) gene, characterized by a recessive allele, display a reduced growth rate and period lengthening of the developmental cycle controlled by the circadian clock. We refined the genetic location of prd-1 and used whole genome sequencing to find the mutation defining it, confirming the identity of prd-1 by rescuing the mutant circadian phenotype via transformation. PRD-1 is an RNA helicase whose orthologs, DDX5 [DEAD (Asp-Glu-Ala-Asp) Box Helicase 5] and DDX17 in humans and DBP2 (Dead Box Protein 2) in yeast, are implicated in various processes, including transcriptional regulation, elongation, and termination, ribosome biogenesis, and mRNA decay. Although prd-1 mutants display a long period (∼25 h) circadian developmental cycle, they interestingly display a WT period when the core circadian oscillator is tracked using a frq-luciferase transcriptional fusion under conditions of limiting nutritional carbon; the core oscillator in the prd-1 mutant strain runs with a long period under glucose-sufficient conditions. Thus, PRD-1 clearly impacts the circadian oscillator and is not only part of a metabolic oscillator ancillary to the core clock. PRD-1 is an essential protein, and its expression is neither light-regulated nor clock-regulated. However, it is transiently induced by glucose; in the presence of sufficient glucose, PRD-1 is in the nucleus until glucose runs out, which elicits its disappearance from the nucleus. Because circadian period length is carbon concentration-dependent, prd-1 may be formally viewed as a clock mutant with defective nutritional compensation of circadian period length.
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Affiliation(s)
- Jillian M Emerson
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | | | - Carol S Ringelberg
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Scott E Baker
- Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99354
| | - Jennifer J Loros
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH 03755; Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Jay C Dunlap
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH 03755;
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