1
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Krueger LA, Morris AC. Generation of a zebrafish knock-in line expressing MYC-tagged Sox11a using CRISPR/Cas9 genome editing. Biochem Biophys Res Commun 2022; 608:8-13. [DOI: 10.1016/j.bbrc.2022.03.103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 03/21/2022] [Indexed: 11/02/2022]
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2
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Wang X, Wang W, Wang Y, Chen J, Liu G, Zhang Y. Antibody-free profiling of transcription factor occupancy during early embryogenesis by FitCUT&RUN. Genome Res 2021; 32:378-388. [PMID: 34965941 PMCID: PMC8805719 DOI: 10.1101/gr.275837.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 12/22/2021] [Indexed: 11/24/2022]
Abstract
Key transcription factors (TFs) play critical roles in zygotic genome activation (ZGA) during early embryogenesis, while genome-wide occupancies of only a few factors have been profiled during ZGA due to the limitation of cell numbers or the lack of high-quality antibodies. Here, we present FitCUT&RUN, a modified CUT&RUN method, in which an Fc fragment of immunoglobulin G is used for tagging, to profile TF occupancy in an antibody-free manner and demonstrate its reliability and robustness using as few as five thousand K562 cells. We applied FitCUT&RUN to zebrafish undergoing embryogenesis to generate reliable occupancy profiles of three known activators of zebrafish ZGA: Nanog, Pou5f3 and Sox19b. By profiling the time-series occupancy of Nanog during zebrafish ZGA, we observed a clear trend toward a gradual increase in Nanog occupancy and found that Nanog occupancy prior to the major phase of ZGA is critical for the activation of a significant proportion of early transcribed genes. Our results further suggested that the sequential binding of Nanog may be controlled by replication timing and the presence of Nanog motifs.
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3
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Tokumoto S, Miyata Y, Deviatiiarov R, Yamada TG, Hiki Y, Kozlova O, Yoshida Y, Cornette R, Funahashi A, Shagimardanova E, Gusev O, Kikawada T. Genome-Wide Role of HSF1 in Transcriptional Regulation of Desiccation Tolerance in the Anhydrobiotic Cell Line, Pv11. Int J Mol Sci 2021; 22:5798. [PMID: 34071490 PMCID: PMC8197945 DOI: 10.3390/ijms22115798] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/24/2021] [Accepted: 05/24/2021] [Indexed: 01/10/2023] Open
Abstract
The Pv11, an insect cell line established from the midge Polypedilum vanderplanki, is capable of extreme hypometabolic desiccation tolerance, so-called anhydrobiosis. We previously discovered that heat shock factor 1 (HSF1) contributes to the acquisition of desiccation tolerance by Pv11 cells, but the mechanistic details have yet to be elucidated. Here, by analyzing the gene expression profiles of newly established HSF1-knockout and -rescue cell lines, we show that HSF1 has a genome-wide effect on gene regulation in Pv11. The HSF1-knockout cells exhibit a reduced desiccation survival rate, but this is completely restored in HSF1-rescue cells. By comparing mRNA profiles of the two cell lines, we reveal that HSF1 induces anhydrobiosis-related genes, especially genes encoding late embryogenesis abundant proteins and thioredoxins, but represses a group of genes involved in basal cellular processes, thus promoting an extreme hypometabolism state in the cell. In addition, HSF1 binding motifs are enriched in the promoters of anhydrobiosis-related genes and we demonstrate binding of HSF1 to these promoters by ChIP-qPCR. Thus, HSF1 directly regulates the transcription of anhydrobiosis-related genes and consequently plays a pivotal role in the induction of anhydrobiotic ability in Pv11 cells.
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Affiliation(s)
- Shoko Tokumoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8562, Japan;
| | - Yugo Miyata
- Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba 305-0851, Japan; (Y.M.); (R.C.)
| | - Ruslan Deviatiiarov
- Extreme Biology Laboratory, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (R.D.); (O.K.); (E.S.); (O.G.)
| | - Takahiro G. Yamada
- Department of Biosciences and Informatics, Keio University, Yokohama 223-8522, Japan; (T.G.Y.); (Y.H.); (A.F.)
| | - Yusuke Hiki
- Department of Biosciences and Informatics, Keio University, Yokohama 223-8522, Japan; (T.G.Y.); (Y.H.); (A.F.)
| | - Olga Kozlova
- Extreme Biology Laboratory, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (R.D.); (O.K.); (E.S.); (O.G.)
| | - Yuki Yoshida
- Institute for Advanced Biosciences, Keio University, Tsuruoka 997-0017, Japan;
- Systems Biology Program, Graduate School of Media and Governance, Keio University, Fujisawa 252-8520, Japan
| | - Richard Cornette
- Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba 305-0851, Japan; (Y.M.); (R.C.)
| | - Akira Funahashi
- Department of Biosciences and Informatics, Keio University, Yokohama 223-8522, Japan; (T.G.Y.); (Y.H.); (A.F.)
| | - Elena Shagimardanova
- Extreme Biology Laboratory, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (R.D.); (O.K.); (E.S.); (O.G.)
| | - Oleg Gusev
- Extreme Biology Laboratory, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (R.D.); (O.K.); (E.S.); (O.G.)
- Laboratory for Transcriptome Technology, RIKEN Center for Integrative Medical Sciences, RIKEN, Yokohama 230-0045, Japan
| | - Takahiro Kikawada
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8562, Japan;
- Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba 305-0851, Japan; (Y.M.); (R.C.)
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4
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Amezian D, Nauen R, Le Goff G. Transcriptional regulation of xenobiotic detoxification genes in insects - An overview. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2021; 174:104822. [PMID: 33838715 DOI: 10.1016/j.pestbp.2021.104822] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/08/2021] [Accepted: 03/02/2021] [Indexed: 05/21/2023]
Abstract
Arthropods have well adapted to the vast array of chemicals they encounter in their environment. Whether these xenobiotics are plant allelochemicals or anthropogenic insecticides one of the strategies they have developed to defend themselves is the induction of detoxification enzymes. Although upregulation of detoxification enzymes and efflux transporters in response to specific inducers has been well described, in insects, yet, little is known on the transcriptional regulation of these genes. Over the past twenty years, an increasing number of studies with insects have used advanced genetic tools such as RNAi, CRISPR/Cas9 and reporter gene assays to dissect the genomic grounds of their xenobiotic response and hence contributed substantially in improving our knowledge on the players involved. Xenobiotics are partly recognized by various "xenobiotic sensors" such as membrane-bound or nuclear receptors. This initiates a molecular reaction cascade ultimately leading to the translocation of a transcription factor to the nucleus that recognizes and binds to short sequences located upstream their target genes to activate transcription. To date, a number of signaling pathways were shown to mediate the upregulation of detoxification enzymes in arthropods and to play a role in either metabolic resistance to insecticides or host-plant adaptation. These include nuclear receptors AhR/ARNT and HR96, GPCRs, CncC and MAPK/CREB. Recent work reveals that upregulation and activation of some components of these pathways as well as polymorphism in the binding motifs of transcription factors are linked to insects' adaptive processes. The aim of this mini-review is to summarize and describe recent work that shed some light on the main regulatory routes of detoxification gene expression in insects.
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Affiliation(s)
- Dries Amezian
- Université Côte d'Azur, INRAE, CNRS, ISA, F-06903 Sophia Antipolis, France
| | - Ralf Nauen
- Bayer AG, Crop Science Division, R&D, Alfred Nobel-Strasse 50, 40789 Monheim, Germany.
| | - Gaëlle Le Goff
- Université Côte d'Azur, INRAE, CNRS, ISA, F-06903 Sophia Antipolis, France.
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5
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Ranawakage DC, Okada K, Sugio K, Kawaguchi Y, Kuninobu-Bonkohara Y, Takada T, Kamachi Y. Efficient CRISPR-Cas9-Mediated Knock-In of Composite Tags in Zebrafish Using Long ssDNA as a Donor. Front Cell Dev Biol 2021; 8:598634. [PMID: 33681181 PMCID: PMC7928300 DOI: 10.3389/fcell.2020.598634] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/31/2020] [Indexed: 12/12/2022] Open
Abstract
Despite the unprecedented gene editing capability of CRISPR-Cas9-mediated targeted knock-in, the efficiency and precision of this technology still require further optimization, particularly for multicellular model organisms, such as the zebrafish (Danio rerio). Our study demonstrated that an ∼200 base-pair sequence encoding a composite tag can be efficiently "knocked-in" into the zebrafish genome using a combination of the CRISPR-Cas9 ribonucleoprotein complex and a long single-stranded DNA (lssDNA) as a donor template. Here, we targeted the sox3, sox11a, and pax6a genes to evaluate the knock-in efficiency of lssDNA donors with different structures in somatic cells of injected embryos and for their germline transmission. The structures and sequence characteristics of the lssDNA donor templates were found to be crucial to achieve a high rate of precise and heritable knock-ins. The following were our key findings: (1) lssDNA donor strand selection is important; however, strand preference and its dependency appear to vary among the target loci or their sequences. (2) The length of the 3' homology arm of the lssDNA donor affects knock-in efficiency in a site-specific manner; particularly, a shorter 50-nt arm length leads to a higher knock-in efficiency than a longer 300-nt arm for the sox3 and pax6a knock-ins. (3) Some DNA sequence characteristics of the knock-in donors and the distance between the CRISPR-Cas9 cleavage site and the tag insertion site appear to adversely affect the repair process, resulting in imprecise editing. By implementing the proposed method, we successfully obtained precisely edited sox3, sox11a, and pax6a knock-in alleles that contained a composite tag composed of FLAGx3 (or PAx3), Bio tag, and HiBiT tag (or His tag) with moderate to high germline transmission rates as high as 21%. Furthermore, the knock-in allele-specific quantitative polymerase chain reaction (qPCR) for both the 5' and 3' junctions indicated that knock-in allele frequencies were higher at the 3' side of the lssDNAs, suggesting that the lssDNA-templated knock-in was mediated by unidirectional single-strand template repair (SSTR) in zebrafish embryos.
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Affiliation(s)
| | | | | | | | | | | | - Yusuke Kamachi
- School of Environmental Science and Engineering, Kochi University of Technology, Kochi, Japan
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6
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Tobias IC, Abatti LE, Moorthy SD, Mullany S, Taylor T, Khader N, Filice MA, Mitchell JA. Transcriptional enhancers: from prediction to functional assessment on a genome-wide scale. Genome 2020; 64:426-448. [PMID: 32961076 DOI: 10.1139/gen-2020-0104] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Enhancers are cis-regulatory sequences located distally to target genes. These sequences consolidate developmental and environmental cues to coordinate gene expression in a tissue-specific manner. Enhancer function and tissue specificity depend on the expressed set of transcription factors, which recognize binding sites and recruit cofactors that regulate local chromatin organization and gene transcription. Unlike other genomic elements, enhancers are challenging to identify because they function independently of orientation, are often distant from their promoters, have poorly defined boundaries, and display no reading frame. In addition, there are no defined genetic or epigenetic features that are unambiguously associated with enhancer activity. Over recent years there have been developments in both empirical assays and computational methods for enhancer prediction. We review genome-wide tools, CRISPR advancements, and high-throughput screening approaches that have improved our ability to both observe and manipulate enhancers in vitro at the level of primary genetic sequences, chromatin states, and spatial interactions. We also highlight contemporary animal models and their importance to enhancer validation. Together, these experimental systems and techniques complement one another and broaden our understanding of enhancer function in development, evolution, and disease.
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Affiliation(s)
- Ian C Tobias
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Luis E Abatti
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Sakthi D Moorthy
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Shanelle Mullany
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Tiegh Taylor
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Nawrah Khader
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Mario A Filice
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Jennifer A Mitchell
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
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7
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Partridge EC, Chhetri SB, Prokop JW, Ramaker RC, Jansen CS, Goh ST, Mackiewicz M, Newberry KM, Brandsmeier LA, Meadows SK, Messer CL, Hardigan AA, Coppola CJ, Dean EC, Jiang S, Savic D, Mortazavi A, Wold BJ, Myers RM, Mendenhall EM. Occupancy maps of 208 chromatin-associated proteins in one human cell type. Nature 2020; 583:720-728. [PMID: 32728244 PMCID: PMC7398277 DOI: 10.1038/s41586-020-2023-4] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/09/2020] [Indexed: 01/02/2023]
Abstract
Transcription factors are DNA-binding proteins that have key roles in gene regulation1,2. Genome-wide occupancy maps of transcriptional regulators are important for understanding gene regulation and its effects on diverse biological processes3–6. However, only a minority of the more than 1,600 transcription factors encoded in the human genome has been assayed. Here we present, as part of the ENCODE (Encyclopedia of DNA Elements) project, data and analyses from chromatin immunoprecipitation followed by high-throughput sequencing (ChIP–seq) experiments using the human HepG2 cell line for 208 chromatin-associated proteins (CAPs). These comprise 171 transcription factors and 37 transcriptional cofactors and chromatin regulator proteins, and represent nearly one-quarter of CAPs expressed in HepG2 cells. The binding profiles of these CAPs form major groups associated predominantly with promoters or enhancers, or with both. We confirm and expand the current catalogue of DNA sequence motifs for transcription factors, and describe motifs that correspond to other transcription factors that are co-enriched with the primary ChIP target. For example, FOX family motifs are enriched in ChIP–seq peaks of 37 other CAPs. We show that motif content and occupancy patterns can distinguish between promoters and enhancers. This catalogue reveals high-occupancy target regions at which many CAPs associate, although each contains motifs for only a minority of the numerous associated transcription factors. These analyses provide a more complete overview of the gene regulatory networks that define this cell type, and demonstrate the usefulness of the large-scale production efforts of the ENCODE Consortium. ChIP–seq and CETCh–seq data are used to analyse binding maps for 208 transcription factors and other chromatin-associated proteins in a single human cell type, providing a comprehensive catalogue of the transcription factor landscape and gene regulatory networks in these cells.
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Affiliation(s)
| | - Surya B Chhetri
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA.,Department of Biological Sciences, The University of Alabama in Huntsville, Huntsville, AL, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MA, USA
| | - Jeremy W Prokop
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA.,Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University, Grand Rapids, MI, USA
| | - Ryne C Ramaker
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA.,Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Camden S Jansen
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA, USA
| | - Say-Tar Goh
- Division of Biology, California Institute of Technology, Pasadena, CA, USA
| | - Mark Mackiewicz
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | | | | | - Sarah K Meadows
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - C Luke Messer
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Andrew A Hardigan
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA.,Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Candice J Coppola
- Department of Biological Sciences, The University of Alabama in Huntsville, Huntsville, AL, USA
| | - Emma C Dean
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA.,Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Shan Jiang
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA, USA
| | - Daniel Savic
- Pharmaceutical Sciences Department, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA, USA
| | - Barbara J Wold
- Division of Biology, California Institute of Technology, Pasadena, CA, USA
| | - Richard M Myers
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA.
| | - Eric M Mendenhall
- HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA. .,Department of Biological Sciences, The University of Alabama in Huntsville, Huntsville, AL, USA.
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8
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Muhammad II, Kong SL, Akmar Abdullah SN, Munusamy U. RNA-seq and ChIP-seq as Complementary Approaches for Comprehension of Plant Transcriptional Regulatory Mechanism. Int J Mol Sci 2019; 21:E167. [PMID: 31881735 PMCID: PMC6981605 DOI: 10.3390/ijms21010167] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 12/19/2019] [Accepted: 12/23/2019] [Indexed: 02/07/2023] Open
Abstract
The availability of data produced from various sequencing platforms offer the possibility to answer complex questions in plant research. However, drawbacks can arise when there are gaps in the information generated, and complementary platforms are essential to obtain more comprehensive data sets relating to specific biological process, such as responses to environmental perturbations in plant systems. The investigation of transcriptional regulation raises different challenges, particularly in associating differentially expressed transcription factors with their downstream responsive genes. In this paper, we discuss the integration of transcriptional factor studies through RNA sequencing (RNA-seq) and Chromatin Immunoprecipitation sequencing (ChIP-seq). We show how the data from ChIP-seq can strengthen information generated from RNA-seq in elucidating gene regulatory mechanisms. In particular, we discuss how integration of ChIP-seq and RNA-seq data can help to unravel transcriptional regulatory networks. This review discusses recent advances in methods for studying transcriptional regulation using these two methods. It also provides guidelines for making choices in selecting specific protocols in RNA-seq pipelines for genome-wide analysis to achieve more detailed characterization of specific transcription regulatory pathways via ChIP-seq.
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Affiliation(s)
- Isiaka Ibrahim Muhammad
- Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, Selangor 43400, Malaysia; (I.I.M.); (S.L.K.); (U.M.)
| | - Sze Ling Kong
- Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, Selangor 43400, Malaysia; (I.I.M.); (S.L.K.); (U.M.)
| | - Siti Nor Akmar Abdullah
- Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, Selangor 43400, Malaysia; (I.I.M.); (S.L.K.); (U.M.)
- Department of Agriculture Technology, Faculty of Agriculture, Universiti Putra Malaysia, Selangor 43400, Malaysia
| | - Umaiyal Munusamy
- Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, Selangor 43400, Malaysia; (I.I.M.); (S.L.K.); (U.M.)
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9
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HiBiT-qIP, HiBiT-based quantitative immunoprecipitation, facilitates the determination of antibody affinity under immunoprecipitation conditions. Sci Rep 2019; 9:6895. [PMID: 31053795 PMCID: PMC6499798 DOI: 10.1038/s41598-019-43319-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 01/31/2019] [Indexed: 12/23/2022] Open
Abstract
The affinity of an antibody for its antigen serves as a critical parameter for antibody evaluation. The evaluation of antibody-antigen affinity is essential for a successful antibody-based assay, particularly immunoprecipitation (IP), due to its strict dependency on antibody performance. However, the determination of antibody affinity or its quantitative determinant, the dissociation constant (Kd), under IP conditions is difficult. In the current study, we used a NanoLuc-based HiBiT system to establish a HiBiT-based quantitative immunoprecipitation (HiBiT-qIP) assay for determining the Kd of antigen-antibody interactions in solution. The HiBiT-qIP method measures the amount of immunoprecipitated proteins tagged with HiBiT in a simple yet quantitative manner. We used this method to measure the Kd values of epitope tag-antibody interactions. To accomplish this, FLAG, HA, V5, PA and Ty1 epitope tags in their monomeric, dimeric or trimeric form were fused with glutathione S-transferase (GST) and the HiBiT peptide, and these tagged GST proteins were mixed with cognate monoclonal antibodies in IP buffer for the assessment of the apparent Kd values. This HiBiT-qIP assay showed a considerable variation in the Kd values among the examined antibody clones. Additionally, the use of epitope tags in multimeric form revealed a copy number-dependent increase in the apparent affinity.
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10
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Policastro RA, Zentner GE. Enzymatic methods for genome-wide profiling of protein binding sites. Brief Funct Genomics 2019; 17:138-145. [PMID: 29028882 DOI: 10.1093/bfgp/elx030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Genome-wide mapping of protein-DNA interactions is a staple approach in many areas of modern molecular biology. Genome-wide profiles of protein-binding sites are most commonly generated by chromatin immunoprecipitation and high-throughput sequencing (ChIP-seq). Although ChIP-seq has played a central role in studying genome-wide protein binding, recent work has highlighted systematic biases in the technique that warrant technical and interpretive caution and underscore the need for orthogonal techniques to both confirm the results of ChIP-seq studies and uncover new insights not accessible to ChIP. Several such techniques, based on genetic or immunological targeting of enzymatic activity to specific genomic loci, have been developed. Here, we review the development, applications and future prospects of these methods as complements to ChIP-based approaches and as powerful techniques in their own right.
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11
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Lyu Q, Dhagia V, Han Y, Guo B, Wines-Samuelson ME, Christie CK, Yin Q, Slivano OJ, Herring P, Long X, Gupte SA, Miano JM. CRISPR-Cas9-Mediated Epitope Tagging Provides Accurate and Versatile Assessment of Myocardin-Brief Report. Arterioscler Thromb Vasc Biol 2018; 38:2184-2190. [PMID: 29976770 PMCID: PMC6204210 DOI: 10.1161/atvbaha.118.311171] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 06/22/2018] [Indexed: 11/16/2022]
Abstract
Objective- Unreliable antibodies often hinder the accurate detection of an endogenous protein, and this is particularly true for the cardiac and smooth muscle cofactor, MYOCD (myocardin). Accordingly, the mouse Myocd locus was targeted with 2 independent epitope tags for the unambiguous expression, localization, and activity of MYOCD protein. Approach and Results- 3cCRISPR (3-component clustered regularly interspaced short palindromic repeat) was used to engineer a carboxyl-terminal 3×FLAG or 3×HA epitope tag in mouse embryos. Western blotting with antibodies to each tag revealed a MYOCD protein product of ≈150 kDa, a size considerably larger than that reported in virtually all publications. MYOCD protein was most abundant in some adult smooth muscle-containing tissues with surprisingly low-level expression in the heart. Both alleles of Myocd are active in aorta because a 2-fold increase in protein was seen in mice homozygous versus heterozygous for FLAG-tagged Myocd. ChIP (chromatin immunoprecipitation)-quantitative polymerase chain reaction studies provide proof-of-principle data demonstrating the utility of this mouse line in conducting genome-wide ChIP-seq studies to ascertain the full complement of MYOCD-dependent target genes in vivo. Although FLAG-tagged MYOCD protein was undetectable in sections of adult mouse tissues, low-passaged vascular smooth muscle cells exhibited expected nuclear localization. Conclusions- This report validates new mouse models for analyzing MYOCD protein expression, localization, and binding activity in vivo and highlights the need for rigorous authentication of antibodies in biomedical research.
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Affiliation(s)
- Qing Lyu
- Aab Cardiovascular Research Institute, University of
Rochester Medical Center, Rochester, NY
| | - Vidhi Dhagia
- Department of Pharmacology, New York Medical College,
Valhalla NY
| | - Yu Han
- Aab Cardiovascular Research Institute, University of
Rochester Medical Center, Rochester, NY
| | - Bing Guo
- Aab Cardiovascular Research Institute, University of
Rochester Medical Center, Rochester, NY
| | - Mary E. Wines-Samuelson
- Aab Cardiovascular Research Institute, University of
Rochester Medical Center, Rochester, NY
| | - Christine K. Christie
- Aab Cardiovascular Research Institute, University of
Rochester Medical Center, Rochester, NY
| | - Qiangzong Yin
- Aab Cardiovascular Research Institute, University of
Rochester Medical Center, Rochester, NY
| | - Orazio J. Slivano
- Aab Cardiovascular Research Institute, University of
Rochester Medical Center, Rochester, NY
| | - Paul Herring
- Department of Cellular and Integrative Physiology, Indiana
University School of Medicine, Indianapolis, IN
| | - Xiaochun Long
- Department of Molecular and Cellular Physiology, Albany
Medical College, Albany, NY 12208
| | - Sachin A. Gupte
- Department of Pharmacology, New York Medical College,
Valhalla NY
| | - Joseph M. Miano
- Aab Cardiovascular Research Institute, University of
Rochester Medical Center, Rochester, NY
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12
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Birkenbihl RP, Liu S, Somssich IE. Transcriptional events defining plant immune responses. CURRENT OPINION IN PLANT BIOLOGY 2017; 38:1-9. [PMID: 28458046 DOI: 10.1016/j.pbi.2017.04.004] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 04/06/2017] [Accepted: 04/10/2017] [Indexed: 05/20/2023]
Abstract
Rapid and massive transcriptional reprogramming upon pathogen recognition is the decisive step in plant-phytopathogen interactions. Plant transcription factors (TFs) are key players in this process but they require a suite of other context-specific co-regulators to establish sensory transcription regulatory networks to bring about host immunity. Molecular, genetic and biochemical studies, particularly in the model plants Arabidopsis and rice, are continuously uncovering new components of the transcriptional machinery that can selectively impact host resistance toward a diverse range of pathogens. Moreover, detailed studies on key immune regulators, such as WRKY TFs and NPR1, are beginning to reveal the underlying mechanisms by which defense hormones influence the function of these factors. Here we provide a short update on such recent developments.
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Affiliation(s)
- Rainer P Birkenbihl
- Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding Research, Carl-von-Linné Weg 10, 50829 Koeln, Germany.
| | - Shouan Liu
- College of Plant Sciences, Jilin University, 130062 Changchun, China.
| | - Imre E Somssich
- Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding Research, Carl-von-Linné Weg 10, 50829 Koeln, Germany.
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