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Bauler M, Ferrara F, Lowe B, Beard JA, Wincek C, Wielgosz MM, Park JJ, Shang N, Nandy S, Li C, Langfitt DM, Zhou S, Throm RE. Genetic alteration of SJ293TS cells and modification of serum-free media enhances lentiviral vector production. Mol Ther Methods Clin Dev 2024; 32:101270. [PMID: 38883976 PMCID: PMC11176759 DOI: 10.1016/j.omtm.2024.101270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 05/17/2024] [Indexed: 06/18/2024]
Abstract
Successful cell and gene therapy clinical trials have resulted in the US Food and Drug Administration and European Medicines Agency approving their use for treatment of patients with certain types of cancers and monogenetic diseases. These novel therapies, which rely heavily on lentiviral vectors to deliver therapeutic transgenes to patient cells, have driven additional investigations, increasing demand for both pre-clinical and current Good Manufacturing Practices-grade viral vectors. To better support novel studies by improving current production methods, we report the development of a genetically modified HEK293T-based cell line that is null for expression of both Protein Kinase R and Beta-2 microglobulin and grows in suspension using serum-free media, SJ293TS-DPB. Absence of Protein Kinase R increased anti-sense lentiviral vector titers by more than 7-fold, while absence of Beta-2 microglobulin, a key component of major histocompatibility complex class I molecules, has been reported to reduce the immunogenicity of lentiviral particles. Furthermore, we describe an improved methodology for culturing SJ293TS-DPB that facilitates expansion, reduces handling, and increases titers by 2-fold compared with previous methods. SJ293TS-DPB stably produced lentiviral vectors for over 4 months and generated lentiviral vectors that efficiently transduce healthy human donor T cells and CD34+ hematopoietic stem cells.
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Affiliation(s)
- Matthew Bauler
- Vector Development and Production Laboratory, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Francesca Ferrara
- Vector Development and Production Laboratory, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Brandon Lowe
- Vector Development and Production Laboratory, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jordan A Beard
- Vector Development and Production Laboratory, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Chris Wincek
- Vector Development and Production Laboratory, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Matthew M Wielgosz
- Vector Development and Production Laboratory, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jeoungeun J Park
- Experimental Cell Therapeutics Lab, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Na Shang
- Experimental Cell Therapeutics Lab, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Saikat Nandy
- Biostatistics, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Cai Li
- Biostatistics, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Deanna M Langfitt
- Bone Marrow Transplant and Cell Therapy, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Sheng Zhou
- Experimental Cell Therapeutics Lab, St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Robert E Throm
- Vector Development and Production Laboratory, St Jude Children's Research Hospital, Memphis, TN 38105, USA
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2
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Archuleta SR, Goodrich JA, Kugel JF. Mechanisms and Functions of the RNA Polymerase II General Transcription Machinery during the Transcription Cycle. Biomolecules 2024; 14:176. [PMID: 38397413 PMCID: PMC10886972 DOI: 10.3390/biom14020176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/29/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024] Open
Abstract
Central to the development and survival of all organisms is the regulation of gene expression, which begins with the process of transcription catalyzed by RNA polymerases. During transcription of protein-coding genes, the general transcription factors (GTFs) work alongside RNA polymerase II (Pol II) to assemble the preinitiation complex at the transcription start site, open the promoter DNA, initiate synthesis of the nascent messenger RNA, transition to productive elongation, and ultimately terminate transcription. Through these different stages of transcription, Pol II is dynamically phosphorylated at the C-terminal tail of its largest subunit, serving as a control mechanism for Pol II elongation and a signaling/binding platform for co-transcriptional factors. The large number of core protein factors participating in the fundamental steps of transcription add dense layers of regulation that contribute to the complexity of temporal and spatial control of gene expression within any given cell type. The Pol II transcription system is highly conserved across different levels of eukaryotes; however, most of the information here will focus on the human Pol II system. This review walks through various stages of transcription, from preinitiation complex assembly to termination, highlighting the functions and mechanisms of the core machinery that participates in each stage.
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Affiliation(s)
| | - James A. Goodrich
- Department of Biochemistry, University of Colorado Boulder, 596 UCB, Boulder, CO 80309, USA;
| | - Jennifer F. Kugel
- Department of Biochemistry, University of Colorado Boulder, 596 UCB, Boulder, CO 80309, USA;
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3
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Davidson C, Wordsworth BP, Cohen CJ, Knight JC, Vecellio M. Chromosome conformation capture approaches to investigate 3D genome architecture in Ankylosing Spondylitis. Front Genet 2023; 14:1129207. [PMID: 36760998 PMCID: PMC9905691 DOI: 10.3389/fgene.2023.1129207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 01/16/2023] [Indexed: 01/26/2023] Open
Abstract
Ankylosing Spondylitis (AS) is a chronic inflammatory arthritis of the spine exhibiting a strong genetic background. The mechanistic and functional understanding of the AS-associated genomic loci, identified with Genome Wide Association Studies (GWAS), remains challenging. Chromosome conformation capture (3C) and derivatives are recent techniques which are of great help in elucidating the spatial genome organization and of enormous support in uncover a mechanistic explanation for disease-associated genetic variants. The perturbation of three-dimensional (3D) genome hierarchy may lead to a plethora of human diseases, including rheumatological disorders. Here we illustrate the latest approaches and related findings on the field of genome organization, highlighting how the instability of 3D genome conformation may be among the causes of rheumatological disease phenotypes. We suggest a new perspective on the inclusive potential of a 3C approach to inform GWAS results in rheumatic diseases. 3D genome organization may ultimately lead to a more precise and comprehensive functional interpretation of AS association, which is the starting point for emerging and more specific therapies.
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Affiliation(s)
- Connor Davidson
- Wellcome Centre of Human Genetics, University of Oxford, Oxford, United Kingdom
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Botnar Research Centre, University of Oxford, Oxford, United Kingdom
| | - B. Paul Wordsworth
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Botnar Research Centre, University of Oxford, Oxford, United Kingdom
| | - Carla J. Cohen
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Botnar Research Centre, University of Oxford, Oxford, United Kingdom
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute for Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Julian C. Knight
- Wellcome Centre of Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Matteo Vecellio
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Botnar Research Centre, University of Oxford, Oxford, United Kingdom
- Centro Ricerche Fondazione Italiana Ricerca Sull’Artrite (FIRA), Fondazione Pisana x la Scienza ONLUS, San Giuliano Terme, Italy
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4
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Bidirectional hybrid erythritol-inducible promoter for synthetic biology in Yarrowia lipolytica. Microb Cell Fact 2023; 22:7. [PMID: 36635727 PMCID: PMC9835291 DOI: 10.1186/s12934-023-02020-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 01/05/2023] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND The oleaginous yeast Yarrowia lipolytica is increasingly used as a chassis strain for generating bioproducts. Several hybrid promoters with different strengths have been developed by combining multiple copies of an upstream activating sequence (UAS) associated with a TATA box and a core promoter. These promoters display either constitutive, phase-dependent, or inducible strong expression. However, there remains a lack of bidirectional inducible promoters for co-expressing genes in Y. lipolytica. RESULTS This study built on our previous work isolating and characterizing the UAS of the erythritol-induced genes EYK1 and EYD1 (UAS-eyk1). We found an erythritol-inducible bidirectional promoter (BDP) located in the EYK1-EYL1 intergenic region. We used the BDP to co-produce YFP and RedStarII fluorescent proteins and demonstrated that the promoter's strength was 2.7 to 3.5-fold stronger in the EYL1 orientation compared to the EYK1 orientation. We developed a hybrid erythritol-inducible bidirectional promoter (HBDP) containing five copies of UAS-eyk1 in both orientations. It led to expression levels 8.6 to 19.2-fold higher than the native bidirectional promoter. While the BDP had a twofold-lower expression level than the strong constitutive TEF promoter, the HBDP had a 5.0-fold higher expression level when oriented toward EYL1 and a 2.4-fold higher expression level when oriented toward EYK1. We identified the optimal media for BDP usage by exploring yeast growth under microbioreactor conditions. Additionally, we constructed novel Golden Gate biobricks and a destination vector for general use. CONCLUSIONS In this research, we developed novel bidirectional and hybrid bidirectional promoters of which expression can be fine-tuned, responding to the need for versatile promoters in the yeast Y. lipolytica. This study provides effective tools that can be employed to smoothly adjust the erythritol-inducible co-expression of two target genes in biotechnology applications. BDPs developed in this study have potential applications in the fields of heterologous protein production, metabolic engineering, and synthetic biology.
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5
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Luan J, Vermunt MW, Syrett CM, Coté A, Tome JM, Zhang H, Huang A, Luppino JM, Keller CA, Giardine BM, Zhang S, Dunagin MC, Zhang Z, Joyce EF, Lis JT, Raj A, Hardison RC, Blobel GA. CTCF blocks antisense transcription initiation at divergent promoters. Nat Struct Mol Biol 2022; 29:1136-1144. [PMID: 36369346 DOI: 10.1101/2021.10.30.465508] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/29/2022] [Indexed: 05/26/2023]
Abstract
Transcription at most promoters is divergent, initiating at closely spaced oppositely oriented core promoters to produce sense transcripts along with often unstable upstream antisense transcripts (uasTrx). How antisense transcription is regulated and to what extent it is coordinated with sense transcription is not well understood. Here, by combining acute degradation of the multi-functional transcription factor CTCF and nascent transcription measurements, we find that CTCF specifically suppresses antisense but not sense transcription at hundreds of divergent promoters. Primary transcript RNA-FISH shows that CTCF lowers burst fraction but not burst intensity of uasTrx and that co-bursting of sense and antisense transcripts is disfavored. Genome editing, chromatin conformation studies and high-resolution transcript mapping revealed that precisely positioned CTCF directly suppresses the initiation of uasTrx, in a manner independent of its architectural function. In sum, CTCF shapes the transcriptional landscape in part by suppressing upstream antisense transcription.
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Affiliation(s)
- Jing Luan
- Medical Scientist Training Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marit W Vermunt
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Camille M Syrett
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Clarion Healthcare, LLC, Boston, MA, USA
| | - Allison Coté
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Jacob M Tome
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Shape Therapeutics Inc, Seattle, WA, USA
| | - Haoyue Zhang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, China
| | - Anran Huang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jennifer M Luppino
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Cheryl A Keller
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Belinda M Giardine
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Shiping Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Margaret C Dunagin
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Zhe Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Eric F Joyce
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Arjun Raj
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Ross C Hardison
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Gerd A Blobel
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
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6
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Luan J, Vermunt MW, Syrett CM, Coté A, Tome JM, Zhang H, Huang A, Luppino JM, Keller CA, Giardine BM, Zhang S, Dunagin MC, Zhang Z, Joyce EF, Lis JT, Raj A, Hardison RC, Blobel GA. CTCF blocks antisense transcription initiation at divergent promoters. Nat Struct Mol Biol 2022; 29:1136-1144. [PMID: 36369346 PMCID: PMC10015438 DOI: 10.1038/s41594-022-00855-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/29/2022] [Indexed: 11/13/2022]
Abstract
Transcription at most promoters is divergent, initiating at closely spaced oppositely oriented core promoters to produce sense transcripts along with often unstable upstream antisense transcripts (uasTrx). How antisense transcription is regulated and to what extent it is coordinated with sense transcription is not well understood. Here, by combining acute degradation of the multi-functional transcription factor CTCF and nascent transcription measurements, we find that CTCF specifically suppresses antisense but not sense transcription at hundreds of divergent promoters. Primary transcript RNA-FISH shows that CTCF lowers burst fraction but not burst intensity of uasTrx and that co-bursting of sense and antisense transcripts is disfavored. Genome editing, chromatin conformation studies and high-resolution transcript mapping revealed that precisely positioned CTCF directly suppresses the initiation of uasTrx, in a manner independent of its architectural function. In sum, CTCF shapes the transcriptional landscape in part by suppressing upstream antisense transcription.
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Affiliation(s)
- Jing Luan
- Medical Scientist Training Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marit W Vermunt
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Camille M Syrett
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Clarion Healthcare, LLC, Boston, MA, USA
| | - Allison Coté
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Jacob M Tome
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Shape Therapeutics Inc, Seattle, WA, USA
| | - Haoyue Zhang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, China
| | - Anran Huang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jennifer M Luppino
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Cheryl A Keller
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Belinda M Giardine
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Shiping Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Margaret C Dunagin
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Zhe Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Eric F Joyce
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Arjun Raj
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Ross C Hardison
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Gerd A Blobel
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
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7
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Unveiling RCOR1 as a rheostat at transcriptionally permissive chromatin. Nat Commun 2022; 13:1550. [PMID: 35322029 PMCID: PMC8943175 DOI: 10.1038/s41467-022-29261-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/01/2022] [Indexed: 12/23/2022] Open
Abstract
RCOR1 is a known transcription repressor that recruits and positions LSD1 and HDAC1/2 on chromatin to erase histone methylation and acetylation. However, there is currently an incomplete understanding of RCOR1’s range of localization and function. Here, we probe RCOR1’s distribution on a genome-wide scale and unexpectedly find that RCOR1 is predominantly associated with transcriptionally active genes. Biochemical analysis reveals that RCOR1 associates with RNA Polymerase II (POL-II) during transcription and deacetylates its carboxy-terminal domain (CTD) at lysine 7. We provide evidence that this non-canonical RCOR1 activity is linked to dampening of POL-II productive elongation at actively transcribing genes. Thus, RCOR1 represses transcription in two ways—first, via a canonical mechanism by erasing transcriptionally permissive histone modifications through associating with HDACs and, second, via a non-canonical mechanism that deacetylates RNA POL-II’s CTD to inhibit productive elongation. We conclude that RCOR1 is a transcription rheostat. The classical neuronal-gene corepressor RCOR1/CoREST is paradoxically enriched in transcriptionally active chromatin. Here the authors show RCOR1 is recruited during promoter-proximal pausing and negatively regulates the nascent-transcript synthesis. They also show that an RCOR1-LSD1- HDAC1 complex removes lysine acetylation from RNA polymerase II to repress transcription.
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8
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Cordon-Obras C, Gomez-Liñan C, Torres-Rusillo S, Vidal-Cobo I, Lopez-Farfan D, Barroso-Del Jesus A, Rojas-Barros D, Carrington M, Navarro M. Identification of sequence-specific promoters driving polycistronic transcription initiation by RNA polymerase II in trypanosomes. Cell Rep 2022; 38:110221. [PMID: 35021094 DOI: 10.1016/j.celrep.2021.110221] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 10/18/2021] [Accepted: 12/15/2021] [Indexed: 11/20/2022] Open
Abstract
Protein-coding genes in trypanosomes occur in polycistronic transcription units (PTUs). How RNA polymerase II (Pol II) initiates transcription of PTUs has not been resolved; the current model favors chromatin modifications inducing transcription rather than sequence-specific promoters. Here, we uncover core promoters by functional characterization of Pol II peaks identified by chromatin immunoprecipitation sequencing (ChIP-seq). Two distinct promoters are located between divergent PTUs, each driving unidirectional transcription. Detailed analysis identifies a 75-bp promoter that is necessary and sufficient to drive full reporter expression and contains functional motifs. Analysis of further promoters suggests transcription initiation is regulated and promoters are either focused or dispersed. In contrast to the previous model of unregulated and promoter-independent transcription initiation, we find that sequence-specific promoters determine the initiation of Pol II transcription of protein-coding genes PTUs. These findings in Trypanosoma brucei suggest that in addition of chromatin modifications, promoter motifs-based regulation of gene expression is deeply conserved among eukaryotes.
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Affiliation(s)
- Carlos Cordon-Obras
- Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas, IPBLN-CSIC, 18016 Granada, Spain
| | - Claudia Gomez-Liñan
- Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas, IPBLN-CSIC, 18016 Granada, Spain
| | - Sara Torres-Rusillo
- Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas, IPBLN-CSIC, 18016 Granada, Spain
| | - Isabel Vidal-Cobo
- Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas, IPBLN-CSIC, 18016 Granada, Spain
| | - Diana Lopez-Farfan
- Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas, IPBLN-CSIC, 18016 Granada, Spain
| | - Alicia Barroso-Del Jesus
- Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas, IPBLN-CSIC, 18016 Granada, Spain
| | - Domingo Rojas-Barros
- Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas, IPBLN-CSIC, 18016 Granada, Spain
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Miguel Navarro
- Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas, IPBLN-CSIC, 18016 Granada, Spain.
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9
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Kim HS. Genetic Interaction Between Site-Specific Epigenetic Marks and Roles of H4v in Transcription Termination in Trypanosoma brucei. Front Cell Dev Biol 2021; 9:744878. [PMID: 34722526 PMCID: PMC8551723 DOI: 10.3389/fcell.2021.744878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/15/2021] [Indexed: 11/13/2022] Open
Abstract
In Trypanosoma brucei, genes are assembled in polycistronic transcription units (PTUs). Boundaries of PTUs are designated transcription start sites and transcription termination sites (TTSs). Messenger RNAs are generated by trans-splicing and polyadenylation of precursor RNAs, and regulatory information in the 3' un-translated region (UTR), rather than promoter activity/sequence-specific transcription factors, controls mRNA levels. Given this peculiar genome structure, special strategies must be utilized to control transcription in T. brucei. TTSs are deposition sites for three non-essential chromatin factors-two of non-canonical histone variants (H3v and H4v) and a DNA modification (base J, which is a hydroxyl-glucosyl dT). This association generated the hypothesis that these three chromatin marks define a transcription termination site in T. brucei. Using a panel of null mutants lacking H3v, H4v, and base J, here I show that H4v is a major sign for transcription termination at TTSs. While having a secondary function at TTSs, H3v is important for monoallelic transcription of telomeric antigen genes. The simultaneous absence of both histone variants leads to proliferation and replication defects, which are exacerbated by the J absence, accompanied by accumulation of sub-G1 population. Thus, I propose that the coordinated actions of H3v, H4v, and J provide compensatory mechanisms for each other in chromatin organization, transcription, replication, and cell-cycle progression.
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Affiliation(s)
- Hee-Sook Kim
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
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10
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Brázda V, Bartas M, Bowater RP. Evolution of Diverse Strategies for Promoter Regulation. Trends Genet 2021; 37:730-744. [PMID: 33931265 DOI: 10.1016/j.tig.2021.04.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 12/15/2022]
Abstract
DNA is fundamentally important for all cellular organisms due to its role as a store of hereditary genetic information. The precise and accurate regulation of gene transcription depends primarily on promoters, which vary significantly within and between genomes. Some promoters are rich in specific types of bases, while others have more varied, complex sequence characteristics. However, it is not only base sequence but also epigenetic modifications and altered DNA structure that regulate promoter activity. Significantly, many promoters across all organisms contain sequences that can form intrastrand hairpins (cruciforms) or four-stranded structures (G-quadruplex or i-motif). In this review we integrate recent studies on promoter regulation that highlight the importance of DNA structure in the evolutionary adaptation of promoter sequences.
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Affiliation(s)
- Václav Brázda
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Martin Bartas
- Department of Biology and Ecology/Institute of Environmental Technologies, Faculty of Science, University of Ostrava, 710 00 Ostrava, Czech Republic
| | - Richard P Bowater
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
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11
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Markus BM, Waldman BS, Lorenzi HA, Lourido S. High-Resolution Mapping of Transcription Initiation in the Asexual Stages of Toxoplasma gondii. Front Cell Infect Microbiol 2021; 10:617998. [PMID: 33553008 PMCID: PMC7854901 DOI: 10.3389/fcimb.2020.617998] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 12/03/2020] [Indexed: 12/13/2022] Open
Abstract
Toxoplasma gondii is a common parasite of humans and animals, causing life-threatening disease in the immunocompromized, fetal abnormalities when contracted during gestation, and recurrent ocular lesions in some patients. Central to the prevalence and pathogenicity of this protozoan is its ability to adapt to a broad range of environments, and to differentiate between acute and chronic stages. These processes are underpinned by a major rewiring of gene expression, yet the mechanisms that regulate transcription in this parasite are only partially characterized. Deciphering these mechanisms requires a precise and comprehensive map of transcription start sites (TSSs); however, Toxoplasma TSSs have remained incompletely defined. To address this challenge, we used 5'-end RNA sequencing to genomically assess transcription initiation in both acute and chronic stages of Toxoplasma. Here, we report an in-depth analysis of transcription initiation at promoters, and provide empirically-defined TSSs for 7603 (91%) protein-coding genes, of which only 1840 concur with existing gene models. Comparing data from acute and chronic stages, we identified instances of stage-specific alternative TSSs that putatively generate mRNA isoforms with distinct 5' termini. Analysis of the nucleotide content and nucleosome occupancy around TSSs allowed us to examine the determinants of TSS choice, and outline features of Toxoplasma promoter architecture. We also found pervasive divergent transcription at Toxoplasma promoters, clustered within the nucleosomes of highly-symmetrical phased arrays, underscoring chromatin contributions to transcription initiation. Corroborating previous observations, we asserted that Toxoplasma 5' leaders are among the longest of any eukaryote studied thus far, displaying a median length of approximately 800 nucleotides. Further highlighting the utility of a precise TSS map, we pinpointed motifs associated with transcription initiation, including the binding sites of the master regulator of chronic-stage differentiation, BFD1, and a novel motif with a similar positional arrangement present at 44% of Toxoplasma promoters. This work provides a critical resource for functional genomics in Toxoplasma, and lays down a foundation to study the interactions between genomic sequences and the regulatory factors that control transcription in this parasite.
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Affiliation(s)
- Benedikt M. Markus
- Whitehead Institute for Biomedical Research, Cambridge, MA, United States
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Benjamin S. Waldman
- Whitehead Institute for Biomedical Research, Cambridge, MA, United States
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, United States
| | | | - Sebastian Lourido
- Whitehead Institute for Biomedical Research, Cambridge, MA, United States
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, United States
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12
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Forey R, Barthe A, Tittel-Elmer M, Wery M, Barrault MB, Ducrot C, Seeber A, Krietenstein N, Szachnowski U, Skrzypczak M, Ginalski K, Rowicka M, Cobb JA, Rando OJ, Soutourina J, Werner M, Dubrana K, Gasser SM, Morillon A, Pasero P, Lengronne A, Poli J. A Role for the Mre11-Rad50-Xrs2 Complex in Gene Expression and Chromosome Organization. Mol Cell 2020; 81:183-197.e6. [PMID: 33278361 DOI: 10.1016/j.molcel.2020.11.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 01/09/2023]
Abstract
Mre11-Rad50-Xrs2 (MRX) is a highly conserved complex with key roles in various aspects of DNA repair. Here, we report a new function for MRX in limiting transcription in budding yeast. We show that MRX interacts physically and colocalizes on chromatin with the transcriptional co-regulator Mediator. MRX restricts transcription of coding and noncoding DNA by a mechanism that does not require the nuclease activity of Mre11. MRX is required to tether transcriptionally active loci to the nuclear pore complex (NPC), and it also promotes large-scale gene-NPC interactions. Moreover, MRX-mediated chromatin anchoring to the NPC contributes to chromosome folding and helps to control gene expression. Together, these findings indicate that MRX has a role in transcription and chromosome organization that is distinct from its known function in DNA repair.
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Affiliation(s)
- Romain Forey
- Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe Labéllisée Ligue contre le Cancer, 34396 Montpellier, France
| | - Antoine Barthe
- Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe Labéllisée Ligue contre le Cancer, 34396 Montpellier, France
| | - Mireille Tittel-Elmer
- Departments of Biochemistry and Molecular Biology and Oncology, Robson DNA Science Centre, Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, T2N 1N4, Canada
| | - Maxime Wery
- Institut Curie, PSL Research University, CNRS UMR 3244, ncRNA, Epigenetic and Genome Fluidity, Université Pierre et Marie Curie, 26 rue d'Ulm, 75248 Paris, France
| | - Marie-Bénédicte Barrault
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Cécile Ducrot
- Institute of Molecular and Cellular Radiobiology, Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA)/Direction de la Recherche Fondamentale (DRF), 92260 Fontenay-aux-Roses Cedex, France
| | - Andrew Seeber
- Center for Advanced Imaging, Harvard University, Cambridge, MA 02138, USA; University of Basel and Friedrich Miescher Institute for Biomedical Research, Faculty of Natural Sciences, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Nils Krietenstein
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Ugo Szachnowski
- Institut Curie, PSL Research University, CNRS UMR 3244, ncRNA, Epigenetic and Genome Fluidity, Université Pierre et Marie Curie, 26 rue d'Ulm, 75248 Paris, France
| | - Magdalena Skrzypczak
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Krzysztof Ginalski
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089 Warsaw, Poland
| | - Maga Rowicka
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Jennifer A Cobb
- Departments of Biochemistry and Molecular Biology and Oncology, Robson DNA Science Centre, Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, T2N 1N4, Canada
| | - Oliver J Rando
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Julie Soutourina
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Michel Werner
- Institut Jacques Monod, CNRS UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013 Paris, France
| | - Karine Dubrana
- Institute of Molecular and Cellular Radiobiology, Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA)/Direction de la Recherche Fondamentale (DRF), 92260 Fontenay-aux-Roses Cedex, France
| | - Susan M Gasser
- University of Basel and Friedrich Miescher Institute for Biomedical Research, Faculty of Natural Sciences, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Antonin Morillon
- Institut Curie, PSL Research University, CNRS UMR 3244, ncRNA, Epigenetic and Genome Fluidity, Université Pierre et Marie Curie, 26 rue d'Ulm, 75248 Paris, France
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe Labéllisée Ligue contre le Cancer, 34396 Montpellier, France
| | - Armelle Lengronne
- Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe Labéllisée Ligue contre le Cancer, 34396 Montpellier, France.
| | - Jérôme Poli
- Institut de Génétique Humaine, CNRS, Université de Montpellier, Equipe Labéllisée Ligue contre le Cancer, 34396 Montpellier, France; University of Basel and Friedrich Miescher Institute for Biomedical Research, Faculty of Natural Sciences, Klingelbergstrasse 50, 4056 Basel, Switzerland.
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13
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Ruiz-Orera J, Villanueva-Cañas JL, Albà MM. Evolution of new proteins from translated sORFs in long non-coding RNAs. Exp Cell Res 2020; 391:111940. [PMID: 32156600 DOI: 10.1016/j.yexcr.2020.111940] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 02/26/2020] [Accepted: 03/02/2020] [Indexed: 01/07/2023]
Abstract
High throughput RNA sequencing techniques have revealed that a large fraction of the genome is transcribed into long non-coding RNAs (lncRNAs). Unlike canonical protein-coding genes, lncRNAs do not contain long open reading frames (ORFs) and tend to be poorly conserved across species. However, many of them contain small ORFs (sORFs) that exhibit translation signatures according to ribosome profiling or proteomics data. These sORFs are a source of putative novel proteins; some of them may confer a selective advantage and be maintained over time, a process known as de novo gene birth. Here we review the mechanisms by which randomly occurring sORFs in lncRNAs can become new functional proteins.
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Affiliation(s)
- Jorge Ruiz-Orera
- Cardiovascular and Metabolic Sciences, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | | | - M Mar Albà
- Evolutionary Genomics Group, Research Programme in Biomedical Informatics, Hospital Del Mar Research Institute (IMIM), Universitat Pompeu Fabra (UPF), Barcelona, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, 08010, Spain.
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14
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A regulatory circuit between lncRNA and TOR directs amino acid uptake in yeast. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118680. [PMID: 32081726 DOI: 10.1016/j.bbamcr.2020.118680] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 02/14/2020] [Accepted: 02/14/2020] [Indexed: 01/09/2023]
Abstract
Long non coding RNAs (lncRNAs) have emerged as crucial players of several central cellular processes across eukaryotes. Target of Rapamycin (TOR) is a central regulator of myriad of fundamental cellular processes including amino acid transport under diverse environmental conditions. Here we investigated the role of lncRNA in TOR regulated amino acid uptake in S. cerevisiae. Transcription of lncRNA regulates local gene expression in eukaryotes. In silico analysis of many genome wide studies in S. cerevisiae revealed that transcriptome includes conditional expression of numerous lncRNAs in proximity to amino acid transporters (AATs). Considering regulatory role of these lncRNAs, we selected highly conserved TOR regulated locus of a pair of AATs present in tandem BAP2 and TAT1. We observed that the expression of antisense lncRNA XUT_2F-154 (TBRT) and AATs BAP2 and TAT1 depends on activities of TOR signaling pathway. The expression of TBRT is induced, while that of BAP2 TAT1 is repressed upon TOR inhibition by Torin2. Notably, upon TOR inhibition loss of TBRT contributed to enhanced activities of Bap2 and Tat1 leading to improved growth. Interestingly, nucleosome scanning assay reveal that TOR signaling pathway governs chromatin remodeling at BAP2 biphasic promoter to control the antagonism of TBRT and BAP2 expression. Further TBRT also reprograms local chromatin landscapes to decrease the transcription of TAT1. The current work demonstrates a functional correlation between lncRNA production and TOR governed amino acid uptake in yeast. Thus this work brings forth a novel avenue for identification of potential regulators for therapeutic interventions against TOR mediated diseases.
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15
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lnc9141-a and -b Play a Different Role in Bovine Myoblast Proliferation, Apoptosis, and Differentiation. MOLECULAR THERAPY. NUCLEIC ACIDS 2019; 18:554-566. [PMID: 31675668 PMCID: PMC6838521 DOI: 10.1016/j.omtn.2019.09.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 05/09/2019] [Accepted: 09/11/2019] [Indexed: 01/28/2023]
Abstract
Previously, our transcriptome sequencing revealed that lnc9141 was differentially expressed in muscles of fetal bovine, calf, and adult bovine, which is considered to provide the basis for raising the muscle mass. In this study, we identified lnc9141 characters. lnc9141 has different transcription start sites and 3′ alternative splicing sites of exon 1, producing lnc9141-a and lnc9141-b transcripts that were highly expressed in the heart and lung. Moreover, neither lnc9141-a nor lnc9141-b had the ability to encode proteins. The functions of lnc9141-a and lnc9141-b were explored by cell cycle, 5-ethynyl-2'-deoxyuridine (EdU), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results showed that lnc9141-a or lnc9141-b overexpression decreased the number of myoblasts in the S phase and increased the proportion of cells in the G0/G1 phase. Furthermore, overexpressing lnc9141-a and lnc9141-b respectively downregulated the expression of Cyclin D1. However, lnc9141-a or lnc9141-b interference was found to increase the number of S-phase myoblasts, and upregulate Cyclin D1 and Cyclin E expression. Through Annexin V-FITC/propidium iodide (PI) double staining and the expression of apoptosis marker genes (Bax, Bcl2, and Caspase-3), it was found that lnc9141-b could regulate the expression of Bax gene. Meantime, high expression of lnc9141-b could decrease MyHC expression. In addition, the intergenic region between lnc9141 and IRX5 was 2.3 kb, with a head-to-head orientation. The study also revealed the core regions of the lnc9141 and IRX5 promoter. Our study demonstrated that both lnc9141-a and -b expression inhibited bovine myoblast proliferation. However, lnc9141-b regulated Bax and MyHC expression. The regulatory mechanism of lnc9141-a and lnc9141-b needs to be further explored.
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16
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Baumgartner EA, Compton ZJ, Evans S, Topczewski J, LeClair EE. Identification of regulatory elements recapitulating early expression of L-plastin in the zebrafish enveloping layer and embryonic periderm. Gene Expr Patterns 2019; 32:53-66. [PMID: 30940554 PMCID: PMC6655599 DOI: 10.1016/j.gep.2019.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/22/2019] [Accepted: 03/24/2019] [Indexed: 12/18/2022]
Abstract
We have cloned and characterized an intronic fragment of zebrafish lymphocyte cytosolic protein 1 (lcp1, also called L-plastin) that drives expression to the zebrafish enveloping layer (EVL). L-plastin is a calcium-dependent actin-bundling protein belonging to the plastin/fimbrin family of proteins, and is necessary for the proper migration and attachment of several adult cell types, including leukocytes and osteoclasts. However, in zebrafish lcp1 is abundantly expressed much earlier, during differentiation of the EVL. The cells of this epithelial layer migrate collectively, spreading vegetally over the yolk. L-plastin expression persists into the larval periderm, a transient epithelial tissue that forms the first larval skin. This finding establishes that L-plastin is activated in two different embryonic waves, with a distinct regulatory switch between the early EVL and the later leukocyte. To better study L-plastin expressing cells we attempted CRISPR/Cas9 homology-driven recombination (HDR) to insert a self-cleaving peptide (Cre-P2A-EGFP-CAAX) downstream of the native lcp1 promoter. This produced a stable zebrafish line expressing Cre recombinase in EVL nuclei and green fluorescence in EVL cell membranes. In vivo tracking of these labeled cells provided enhanced views of EVL migration behavior, membrane extensions, and mitotic events. Finally, we experimentally dissected key elements of the targeted lcp1 locus, discovering a ∼300 bp intronic sequence sufficient to drive EVL expression. The lcp1: Cre-P2A-EGFP-CAAX zebrafish should be useful for studying enveloping layer specification, gastrulation movements and periderm development in this widely used vertebrate model. In addition, the conserved regulatory sequences we have isolated predict that L-plastin orthologs may have a similar early expression pattern in other vertebrate embryos.
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Affiliation(s)
| | | | - Spencer Evans
- Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, USA
| | - Jacek Topczewski
- Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, USA; Department of Pediatrics, Northwestern University Feinberg School of Medicine, USA; Department of Biochemistry and Molecular Biology, Medical University of Lublin, Poland
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17
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Corney BPA, Widnall CL, Rees DJ, Davies JS, Crunelli V, Carter DA. Regulatory Architecture of the Neuronal Cacng2/Tarpγ2 Gene Promoter: Multiple Repressive Domains, a Polymorphic Regulatory Short Tandem Repeat, and Bidirectional Organization with Co-regulated lncRNAs. J Mol Neurosci 2018; 67:282-294. [PMID: 30478755 PMCID: PMC6373327 DOI: 10.1007/s12031-018-1208-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 11/08/2018] [Indexed: 12/14/2022]
Abstract
CACNG2 (TARPγ2, Stargazin) is a multi-functional regulator of excitatory neurotransmission and has been implicated in the pathological processes of several brain diseases. Cacng2 function is dependent upon expression level, but currently, little is known about the molecular mechanisms that control expression of this gene. To address this deficit and investigate disease-related gene variants, we have cloned and characterized the rat Cacng2 promoter and have defined three major features: (i) multiple repressive domains that include an array of RE-1 silencing transcription factor (REST) elements, and a calcium regulatory element-binding factor (CaRF) element, (ii) a (poly-GA) short tandem repeat (STR), and (iii) bidirectional organization with expressed lncRNAs. Functional activity of the promoter was demonstrated in transfected neuronal cell lines (HT22 and PC12), but although selective removal of REST and CaRF domains was shown to enhance promoter-driven transcription, the enhanced Cacng2 promoter constructs were still about fivefold weaker than a comparable rat Synapsin-1 promoter sequence. Direct evidence of REST activity at the Cacng2 promoter was obtained through co-transfection with an established dominant-negative REST (DNR) construct. Investigation of the GA-repeat STR revealed polymorphism across both animal strains and species, and size variation was also observed in absence epilepsy disease model cohorts (Genetic Absence Epilepsy Rats, Strasbourg [GAERS] and non-epileptic control [NEC] rats). These data provide evidence of a genotype (STR)-phenotype correlation that may be unique with respect to proximal gene regulatory sequence in the demonstrated absence of other promoter, or 3' UTR variants in GAERS rats. However, although transcriptional regulatory activity of the STR was demonstrated in further transfection studies, we did not find a GAERS vs. NEC difference, indicating that this specific STR length variation may only be relevant in the context of other (Cacna1h and Kcnk9) gene variants in this disease model. Additional studies revealed further (bidirectional) complexity at the Cacng2 promoter, and we identified novel, co-regulated, antisense rat lncRNAs that are paired with Cacng2 mRNA. These studies have provided novel insights into the organization of a synaptic protein gene promoter, describing multiple repressive and modulatory domains that can mediate diverse regulatory inputs.
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Affiliation(s)
- B P A Corney
- School of Biosciences, Cardiff University, CF103AX, Cardiff, UK
| | - C L Widnall
- School of Biosciences, Cardiff University, CF103AX, Cardiff, UK
| | - D J Rees
- Molecular Neurobiology, Institute of Life Science, Swansea University, Swansea, SA2 8PP, UK
| | - J S Davies
- Molecular Neurobiology, Institute of Life Science, Swansea University, Swansea, SA2 8PP, UK
| | - V Crunelli
- School of Biosciences, Cardiff University, CF103AX, Cardiff, UK
| | - D A Carter
- School of Biosciences, Cardiff University, CF103AX, Cardiff, UK.
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18
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Behjati Ardakani F, Kattler K, Nordström K, Gasparoni N, Gasparoni G, Fuchs S, Sinha A, Barann M, Ebert P, Fischer J, Hutter B, Zipprich G, Imbusch CD, Felder B, Eils J, Brors B, Lengauer T, Manke T, Rosenstiel P, Walter J, Schulz MH. Integrative analysis of single-cell expression data reveals distinct regulatory states in bidirectional promoters. Epigenetics Chromatin 2018; 11:66. [PMID: 30414612 PMCID: PMC6230222 DOI: 10.1186/s13072-018-0236-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 10/26/2018] [Indexed: 01/12/2023] Open
Abstract
Background Bidirectional promoters (BPs) are prevalent in eukaryotic genomes. However, it is poorly understood how the cell integrates different epigenomic information, such as transcription factor (TF) binding and chromatin marks, to drive gene expression at BPs. Single-cell sequencing technologies are revolutionizing the field of genome biology. Therefore, this study focuses on the integration of single-cell RNA-seq data with bulk ChIP-seq and other epigenetics data, for which single-cell technologies are not yet established, in the context of BPs. Results We performed integrative analyses of novel human single-cell RNA-seq (scRNA-seq) data with bulk ChIP-seq and other epigenetics data. scRNA-seq data revealed distinct transcription states of BPs that were previously not recognized. We find associations between these transcription states to distinct patterns in structural gene features, DNA accessibility, histone modification, DNA methylation and TF binding profiles. Conclusions Our results suggest that a complex interplay of all of these elements is required to achieve BP-specific transcriptional output in this specialized promoter configuration. Further, our study implies that novel statistical methods can be developed to deconvolute masked subpopulations of cells measured with different bulk epigenomic assays using scRNA-seq data. Electronic supplementary material The online version of this article (10.1186/s13072-018-0236-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Fatemeh Behjati Ardakani
- Excellence Cluster for Multimodal Computing and Interaction, Saarland Informatics Campus, Saarland University, Campus E1 7, Saarbrücken, 66123, Germany.,Department of Computational Biology and Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics, Campus E 4, Saarbrücken, 66123, Germany.,Graduate School of Computer Science, Saarland University, Campus E1 3, Saarbrücken, 66123, Germany
| | - Kathrin Kattler
- Department of Genetics, University of Saarland, Campus A2 4, Saarbrücken, 66123, Germany
| | - Karl Nordström
- Department of Genetics, University of Saarland, Campus A2 4, Saarbrücken, 66123, Germany
| | - Nina Gasparoni
- Department of Genetics, University of Saarland, Campus A2 4, Saarbrücken, 66123, Germany
| | - Gilles Gasparoni
- Department of Genetics, University of Saarland, Campus A2 4, Saarbrücken, 66123, Germany
| | - Sarah Fuchs
- Department of Genetics, University of Saarland, Campus A2 4, Saarbrücken, 66123, Germany
| | - Anupam Sinha
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Rosalind-Franklin-Str. 12, Kiel, 24105, Germany
| | - Matthias Barann
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Rosalind-Franklin-Str. 12, Kiel, 24105, Germany
| | - Peter Ebert
- Department of Computational Biology and Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics, Campus E 4, Saarbrücken, 66123, Germany.,Graduate School of Computer Science, Saarland University, Campus E1 3, Saarbrücken, 66123, Germany
| | - Jonas Fischer
- Excellence Cluster for Multimodal Computing and Interaction, Saarland Informatics Campus, Saarland University, Campus E1 7, Saarbrücken, 66123, Germany.,Department of Computational Biology and Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics, Campus E 4, Saarbrücken, 66123, Germany.,Graduate School of Computer Science, Saarland University, Campus E1 3, Saarbrücken, 66123, Germany
| | - Barbara Hutter
- Applied Bioinformatics, Deutsches Krebsforschungszentrum, Berliner-Str. 41, Heidelberg, 69120, Germany
| | - Gideon Zipprich
- Data Management and Genomics IT, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, Heidelberg, 69120, Germany
| | - Charles D Imbusch
- Applied Bioinformatics, Deutsches Krebsforschungszentrum, Berliner-Str. 41, Heidelberg, 69120, Germany
| | - Bärbel Felder
- Data Management and Genomics IT, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, Heidelberg, 69120, Germany
| | - Jürgen Eils
- Data Management and Genomics IT, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, Heidelberg, 69120, Germany
| | - Benedikt Brors
- Applied Bioinformatics, Deutsches Krebsforschungszentrum, Berliner-Str. 41, Heidelberg, 69120, Germany
| | - Thomas Lengauer
- Department of Computational Biology and Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics, Campus E 4, Saarbrücken, 66123, Germany
| | - Thomas Manke
- Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, Freiburg, 79108, Germany
| | - Philip Rosenstiel
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Rosalind-Franklin-Str. 12, Kiel, 24105, Germany
| | - Jörn Walter
- Department of Genetics, University of Saarland, Campus A2 4, Saarbrücken, 66123, Germany
| | - Marcel H Schulz
- Excellence Cluster for Multimodal Computing and Interaction, Saarland Informatics Campus, Saarland University, Campus E1 7, Saarbrücken, 66123, Germany. .,Department of Computational Biology and Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics, Campus E 4, Saarbrücken, 66123, Germany. .,Institute for Cardiovascular Regeneration, Goethe University, Theodor-Stern-Kai 7, Frankfurt am Main, 60590, Germany. .,German Center for Cardiovascular Research, Partner site Rhein-Main, Frankfurt am Main, 60590, Germany.
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19
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Chiu AC, Suzuki HI, Wu X, Mahat DB, Kriz AJ, Sharp PA. Transcriptional Pause Sites Delineate Stable Nucleosome-Associated Premature Polyadenylation Suppressed by U1 snRNP. Mol Cell 2018; 69:648-663.e7. [PMID: 29398447 DOI: 10.1016/j.molcel.2018.01.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/21/2017] [Accepted: 01/04/2018] [Indexed: 12/16/2022]
Abstract
Regulation of RNA polymerase II (Pol II) elongation is a critical step in gene regulation. Here, we report that U1 snRNP recognition and transcription pausing at stable nucleosomes are linked through premature polyadenylation signal (PAS) termination. By generating RNA exosome conditional deletion mouse embryonic stem cells, we identified a large class of polyadenylated short transcripts in the sense direction destabilized by the RNA exosome. These PAS termination events are enriched at the first few stable nucleosomes flanking CpG islands and suppressed by U1 snRNP. Thus, promoter-proximal Pol II pausing consists of two processes: TSS-proximal and +1 stable nucleosome pausing, with PAS termination coinciding with the latter. While pausing factors NELF/DSIF only function in the former step, flavopiridol-sensitive mechanism(s) and Myc modulate both steps. We propose that premature PAS termination near the nucleosome-associated pause site represents a common transcriptional elongation checkpoint regulated by U1 snRNP recognition, nucleosome stability, and Myc activity.
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Affiliation(s)
- Anthony C Chiu
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Hiroshi I Suzuki
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Xuebing Wu
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Dig B Mahat
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Andrea J Kriz
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Phillip A Sharp
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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20
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Zuin J, Casa V, Pozojevic J, Kolovos P, van den Hout MCGN, van Ijcken WFJ, Parenti I, Braunholz D, Baron Y, Watrin E, Kaiser FJ, Wendt KS. Regulation of the cohesin-loading factor NIPBL: Role of the lncRNA NIPBL-AS1 and identification of a distal enhancer element. PLoS Genet 2017; 13:e1007137. [PMID: 29261648 PMCID: PMC5754091 DOI: 10.1371/journal.pgen.1007137] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 01/04/2018] [Accepted: 11/28/2017] [Indexed: 12/13/2022] Open
Abstract
Cohesin is crucial for genome stability, cell division, transcription and chromatin organization. Its functions critically depend on NIPBL, the cohesin-loader protein that is found to be mutated in >60% of the cases of Cornelia de Lange syndrome (CdLS). Other mutations are described in the cohesin subunits SMC1A, RAD21, SMC3 and the HDAC8 protein. In 25-30% of CdLS cases no mutation in the known CdLS genes is detected. Until now, functional elements in the noncoding genome were not characterized in the molecular etiology of CdLS and therefore are excluded from mutation screening, although the impact of such mutations has now been recognized for a wide range of diseases. We have identified different elements of the noncoding genome involved in regulation of the NIPBL gene. NIPBL-AS1 is a long non-coding RNA transcribed upstream and antisense to NIPBL. By knockdown and transcription blocking experiments, we could show that not the NIPBL-AS1 gene product, but its actual transcription is important to regulate NIPBL expression levels. This reveals a possibility to boost the transcriptional activity of the NIPBL gene by interfering with the NIPBL-AS1 lncRNA. Further, we have identified a novel distal enhancer regulating both NIPBL and NIPBL-AS1. Deletion of the enhancer using CRISPR genome editing in HEK293T cells reduces expression of NIPBL, NIPBL-AS1 as well as genes found to be dysregulated in CdLS.
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MESH Headings
- Cell Cycle Proteins/genetics
- Cell Cycle Proteins/metabolism
- Chromosomal Proteins, Non-Histone/genetics
- Chromosomal Proteins, Non-Histone/metabolism
- Chromosome Segregation
- De Lange Syndrome/genetics
- Enhancer Elements, Genetic
- Gene Expression Regulation
- Genome, Human
- HEK293 Cells
- Humans
- Mutation
- Oligonucleotides, Antisense/genetics
- Oligonucleotides, Antisense/metabolism
- Phenotype
- Promoter Regions, Genetic
- Proteins/genetics
- Proteins/metabolism
- RNA, Long Noncoding/genetics
- RNA, Long Noncoding/metabolism
- Sequence Analysis, DNA
- Cohesins
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Affiliation(s)
- Jessica Zuin
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
| | - Valentina Casa
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
| | - Jelena Pozojevic
- Section for Functional Genetics at the Institute of Human Genetics, University of Lübeck, Lübeck, Germany
| | - Petros Kolovos
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
| | | | | | - Ilaria Parenti
- Section for Functional Genetics at the Institute of Human Genetics, University of Lübeck, Lübeck, Germany
| | | | - Yorann Baron
- Centre National de la Recherche Scientifique, UMR 6290, Rennes, France
- Institut de Génétique et Développement de Rennes, Faculté de Médecine, Rennes, France
| | - Erwan Watrin
- Centre National de la Recherche Scientifique, UMR 6290, Rennes, France
- Institut de Génétique et Développement de Rennes, Faculté de Médecine, Rennes, France
| | - Frank J. Kaiser
- Section for Functional Genetics at the Institute of Human Genetics, University of Lübeck, Lübeck, Germany
| | - Kerstin S. Wendt
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
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Chicken CCDC152 shares an NFYB-regulated bidirectional promoter with a growth hormone receptor antisense transcript and inhibits cells proliferation and migration. Oncotarget 2017; 8:84039-84053. [PMID: 29137403 PMCID: PMC5663575 DOI: 10.18632/oncotarget.21091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 09/04/2017] [Indexed: 12/11/2022] Open
Abstract
The chicken coiled-coil domain-containing protein 152 (CCDC152) recently has been identified as a novel one implicated in cell cycle regulation, cellular proliferation and migration by us. Here we demonstrate that CCDC152 is oriented in a head-to-head configuration with the antisense transcript of growth hormone receptor (GHR) gene. Through serial luciferase reporter assays, we firstly identified a minimal 102 bp intergenic region as a core bidirectional promoter to drive basal transcription in divergent orientations. And site mutation and transient transfected assays showed that nuclear transcription factor Y subunit beta (NFYB) could bind to the CCAAT box and directly transactivate this bidirectional promoter. SiRNA-mediated NFYB depletion could significantly down-regulate the expression of both GHR-AS-I6 and CCDC152. Additionally, the expression of GHR-AS-I6 was significantly up-regulated after CCDC152 overexpression. Overexpression of CCDC152 remarkably reduced cell proliferation and migration through JAK2/STAT signaling pathway. Thus, the GHR-AS-I6-CCDC152 bidirectional transcription unit, as a novel direct target of NFYB, is possibly essential for the accelerated proliferation and motility of different cells.
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22
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Xu W, Xu H, Li K, Fan Y, Liu Y, Yang X, Sun Q. The R-loop is a common chromatin feature of the Arabidopsis genome. NATURE PLANTS 2017; 3:704-714. [PMID: 28848233 DOI: 10.1038/s41477-017-0004-x] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 07/14/2017] [Indexed: 05/03/2023]
Abstract
R-loops are functional structures in chromatin comprising one single-stranded DNA and a DNA:RNA hybrid. Here, we report ssDRIP-seq, a single-strand DNA ligation-based library preparation technique for genome-wide identification of R-loops. When applied in Arabidopsis, ssDRIP-seq exhibits high efficiency, low bias and strand specificity. We found that Arabidopsis R-loops are enriched by both AT and GC skews, and are formed in the sense and antisense orientations. R-loops are strongly enriched in gene promoters and gene bodies, and are highly associated with noncoding RNA and repetitive genomic regions. Furthermore, R-loops are negatively correlated with CG DNA hypermethylation, and are prevalent in regions with multiple chromatin modifications, showing strong correlations with the activated and repressed gene loci. Our analyses indicate that R-loops are common features in the Arabidopsis genome and suggest that the R-loops play diverse roles in genome organization and gene regulation, thereby providing insights into plant nuclear genome formation and function.
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Affiliation(s)
- Wei Xu
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, 100084, China
- Center for Plant Biology, Tsinghua University, Beijing, 100084, China
| | - Hui Xu
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, 100084, China
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Kuan Li
- Center for Plant Biology, Tsinghua University, Beijing, 100084, China
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yingxu Fan
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, 100084, China
- Center for Plant Biology, Tsinghua University, Beijing, 100084, China
| | - Yang Liu
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, 100084, China
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xuerui Yang
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, 100084, China.
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
| | - Qianwen Sun
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, 100084, China.
- Center for Plant Biology, Tsinghua University, Beijing, 100084, China.
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23
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Gallegos JE, Rose AB. Intron DNA Sequences Can Be More Important Than the Proximal Promoter in Determining the Site of Transcript Initiation. THE PLANT CELL 2017; 29:843-853. [PMID: 28373518 PMCID: PMC5435436 DOI: 10.1105/tpc.17.00020] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/12/2017] [Accepted: 03/30/2017] [Indexed: 05/20/2023]
Abstract
To more precisely define the positions from which certain intronic regulatory sequences increase mRNA accumulation, the effect of a UBIQUITIN intron on gene expression was tested from six different positions surrounding the transcription start site (TSS) of a reporter gene fusion in Arabidopsis thaliana The intron increased expression from all transcribed positions but had no effect when upstream of the 5'-most TSS. While this implies that the intron must be transcribed to increase expression, the TSS changed when the intron was located in the 5'-untranslated region (UTR), suggesting that the intron affects transcription initiation. Remarkably, deleting 303 nucleotides of the promoter including all known TSSs and all but 18 nucleotides of the 5'-UTR had virtually no effect on the level of gene expression as long as an intron containing stimulatory sequences was included. Instead, transcription was initiated in normally untranscribed sequences the same distance upstream of the intron as when the promoter was intact. These results suggest that certain intronic DNA sequences play unexpectedly large roles in directing transcription initiation and constitute a previously unrecognized type of downstream regulatory element for genes transcribed by RNA polymerase II.
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Affiliation(s)
- Jenna E Gallegos
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616
| | - Alan B Rose
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616
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24
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Wang X, Kültz D. Osmolality/salinity-responsive enhancers (OSREs) control induction of osmoprotective genes in euryhaline fish. Proc Natl Acad Sci U S A 2017; 114:E2729-E2738. [PMID: 28289196 PMCID: PMC5380061 DOI: 10.1073/pnas.1614712114] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Fish respond to salinity stress by transcriptional induction of many genes, but the mechanism of their osmotic regulation is unknown. We developed a reporter assay using cells derived from the brain of the tilapia Oreochromis mossambicus (OmB cells) to identify osmolality/salinity-responsive enhancers (OSREs) in the genes of Omossambicus Genomic DNA comprising the regulatory regions of two strongly salinity-induced genes, inositol monophosphatase 1 (IMPA1.1) and myo-inositol phosphate synthase (MIPS), was isolated and analyzed with dual luciferase enhancer trap reporter assays. We identified five sequences (two in IMPA1.1 and three in MIPS) that share a common consensus element (DDKGGAAWWDWWYDNRB), which we named "OSRE1." Additional OSREs that were less effective in conferring salinity-induced trans-activation and do not match the OSRE1 consensus also were identified in both MIPS and IMPA1.1 Although OSRE1 shares homology with the mammalian osmotic-response element/tonicity-responsive enhancer (ORE/TonE) enhancer, the latter is insufficient to confer osmotic induction in fish. Like other enhancers, OSRE1 trans-activates genes independent of orientation. We conclude that OSRE1 is a cis-regulatory element (CRE) that enhances the hyperosmotic induction of osmoregulated genes in fish. Our study also shows that tailored reporter assays developed for OmB cells facilitate the identification of CREs in fish genomes. Knowledge of the OSRE1 motif allows affinity-purification of the corresponding transcription factor and computational approaches for enhancer screening of fish genomes. Moreover, our study enables targeted inactivation of OSRE1 enhancers, a method superior to gene knockout for functional characterization because it confines impairment of gene function to a specific context (salinity stress) and eliminates pitfalls of constitutive gene knockouts (embryonic lethality, developmental compensation).
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Affiliation(s)
- Xiaodan Wang
- Biochemical Evolution Laboratory, Department of Animal Science, University of California, Davis, CA, 95616
- Laboratory of Aquaculture Nutrition and Environmental Health, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Dietmar Kültz
- Biochemical Evolution Laboratory, Department of Animal Science, University of California, Davis, CA, 95616;
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25
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Doyle JJ. Chasing unicorns: Nodulation origins and the paradox of novelty. AMERICAN JOURNAL OF BOTANY 2016; 103:1865-1868. [PMID: 27756731 DOI: 10.3732/ajb.1600260] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 08/31/2016] [Indexed: 05/25/2023]
Affiliation(s)
- Jeff J Doyle
- School of Integrative Plant Science, Section of Plant Breeding & Genetics and Section of Plant Biology, 240 Emerson Hall, Cornell University, Ithaca, New York 14853 USA
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