1
|
Silver BD, Willett CG, Maher KA, Wang D, Deal RB. Differences in transcription initiation directionality underlie distinctions between plants and animals in chromatin modification patterns at genes and cis-regulatory elements. G3 (BETHESDA, MD.) 2024; 14:jkae016. [PMID: 38253712 PMCID: PMC10917500 DOI: 10.1093/g3journal/jkae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 11/10/2023] [Accepted: 01/11/2024] [Indexed: 01/24/2024]
Abstract
Transcriptional initiation is among the first regulated steps controlling eukaryotic gene expression. High-throughput profiling of fungal and animal genomes has revealed that RNA Polymerase II often initiates transcription in both directions at the promoter transcription start site, but generally only elongates productively into the gene body. Additionally, Pol II can initiate transcription in both directions at cis-regulatory elements such as enhancers. These bidirectional RNA Polymerase II initiation events can be observed directly with methods that capture nascent transcripts, and they are also revealed indirectly by the presence of transcription-associated histone modifications on both sides of the transcription start site or cis-regulatory elements. Previous studies have shown that nascent RNAs and transcription-associated histone modifications in the model plant Arabidopsis thaliana accumulate mainly in the gene body, suggesting that transcription does not initiate widely in the upstream direction from genes in this plant. We compared transcription-associated histone modifications and nascent transcripts at both transcription start sites and cis-regulatory elements in A. thaliana, Drosophila melanogaster, and Homo sapiens. Our results provide evidence for mostly unidirectional RNA Polymerase II initiation at both promoters and gene-proximal cis-regulatory elements of A. thaliana, whereas bidirectional transcription initiation is observed widely at promoters in both D. melanogaster and H. sapiens, as well as cis-regulatory elements in Drosophila. Furthermore, the distribution of transcription-associated histone modifications around transcription start sites in the Oryza sativa (rice) and Glycine max (soybean) genomes suggests that unidirectional transcription initiation is the norm in these genomes as well. These results suggest that there are fundamental differences in transcriptional initiation directionality between flowering plant and metazoan genomes, which are manifested as distinct patterns of chromatin modifications around RNA polymerase initiation sites.
Collapse
Affiliation(s)
- Brianna D Silver
- Department of Biology, Emory University, Atlanta, GA 30322, USA
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322, USA
| | - Courtney G Willett
- Department of Biology, Emory University, Atlanta, GA 30322, USA
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322, USA
| | - Kelsey A Maher
- Department of Biology, Emory University, Atlanta, GA 30322, USA
- Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University, Atlanta, GA 30322, USA
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Dongxue Wang
- Department of Biology, Emory University, Atlanta, GA 30322, USA
- School of Medicine, Emory University, Atlanta, GA 30322, USA
| | - Roger B Deal
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| |
Collapse
|
2
|
Silver BD, Willett CG, Maher KA, Wang D, Deal RB. Differences in transcription initiation directionality underlie distinctions between plants and animals in chromatin modification patterns at genes and cis-regulatory elements. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.03.565513. [PMID: 37961418 PMCID: PMC10635121 DOI: 10.1101/2023.11.03.565513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Transcriptional initiation is among the first regulated steps controlling eukaryotic gene expression. High-throughput profiling of fungal and animal genomes has revealed that RNA Polymerase II (Pol II) often initiates transcription in both directions at the promoter transcription start site (TSS), but generally only elongates productively into the gene body. Additionally, Pol II can initiate transcription in both directions at cis-regulatory elements (CREs) such as enhancers. These bidirectional Pol II initiation events can be observed directly with methods that capture nascent transcripts, and they are also revealed indirectly by the presence of transcription-associated histone modifications on both sides of the TSS or CRE. Previous studies have shown that nascent RNAs and transcription-associated histone modifications in the model plant Arabidopsis thaliana accumulate mainly in the gene body, suggesting that transcription does not initiate widely in the upstream direction from genes in this plant. We compared transcription-associated histone modifications and nascent transcripts at both TSSs and CREs in Arabidopsis thaliana, Drosophila melanogaster, and Homo sapiens. Our results provide evidence for mostly unidirectional Pol II initiation at both promoters and gene-proximal CREs of Arabidopsis thaliana, whereas bidirectional transcription initiation is observed widely at promoters in both Drosophila melanogaster and Homo sapiens, as well as CREs in Drosophila. Furthermore, the distribution of transcription-associated histone modifications around TSSs in the Oryza sativa (rice) and Glycine max (soybean) genomes suggests that unidirectional transcription initiation is the norm in these genomes as well. These results suggest that there are fundamental differences in transcriptional initiation directionality between flowering plant and metazoan genomes, which are manifested as distinct patterns of chromatin modifications around RNA polymerase initiation sites.
Collapse
Affiliation(s)
- Brianna D. Silver
- Department of Biology, Emory University, Atlanta, GA 30322 USA
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322 USA
| | - Courtney G. Willett
- Department of Biology, Emory University, Atlanta, GA 30322 USA
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322 USA
| | - Kelsey A. Maher
- Department of Biology, Emory University, Atlanta, GA 30322 USA
- Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University, Atlanta, GA 30322 USA
| | - Dongxue Wang
- Department of Biology, Emory University, Atlanta, GA 30322 USA
| | - Roger B. Deal
- Department of Biology, Emory University, Atlanta, GA 30322 USA
| |
Collapse
|
3
|
Heisler MG, Jönsson H, Wenkel S, Kaufmann K. Context-specific functions of transcription factors controlling plant development: From leaves to flowers. CURRENT OPINION IN PLANT BIOLOGY 2022; 69:102262. [PMID: 35952407 DOI: 10.1016/j.pbi.2022.102262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/14/2022] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
Plant development is regulated by transcription factors that often act in more than one process and stage of development. Yet the molecular mechanisms that govern the functional diversity and specificity of these proteins remains far from understood. Flower development provides an ideal context to study these mechanisms since the development of distinct floral organs depends on similar but distinct combinations of transcriptional regulators. Recent work also highlights the importance of leaf polarity regulators as additional key factors in flower initiation, floral organ morphogenesis, and possibly floral organ positioning. A detailed understanding of how these factors work in combination will enable us to address outstanding questions in flower development including how distinct shapes and positions of floral organs are generated. Experimental approaches and computer-based modeling will be required to characterize gene-regulatory networks at the level of single cells.
Collapse
Affiliation(s)
- Marcus G Heisler
- School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia
| | - Henrik Jönsson
- Sainsbury Laboratory, University of Cambridge, UK; Department of Applied Mathematics and Theoretical Physics, University of Cambridge, UK; Computational Biology and Biological Physics, Lund University, Sweden
| | - Stephan Wenkel
- Department of Plant & Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Kerstin Kaufmann
- Humboldt-Universität zu Berlin, Institute of Biology, Philippstr. 13, 10115, Berlin, Germany.
| |
Collapse
|
4
|
Chu Y, Gong J, Wu P, Liu Y, Du Y, Ma L, Fu D, Zhu H, Qu G, Zhu B. Deciphering Precise Gene Transcriptional Expression Using gwINTACT in Tomato. FRONTIERS IN PLANT SCIENCE 2022; 13:852206. [PMID: 35498641 PMCID: PMC9048029 DOI: 10.3389/fpls.2022.852206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 03/09/2022] [Indexed: 06/14/2023]
Abstract
Functional gene transcription mainly occurs in the nucleus and has a significant role in plant physiology. The isolation of nuclei tagged in specific cell type (INTACT) technique provides an efficient and stable nucleus purification method to investigate the dynamic changes of nuclear gene transcriptional expression. However, the application of traditional INTACT in plants is still limited to seedlings or root cells because of severe chloroplast pollution. In this study, we proposed a newly designed and simplified INTACT based on mas-enhanced GFP (eGFP)-SlWIP2 (gwINTACT) for nuclear purification in tomato (Solanum lycopersicum) leaves, flowers, and fruits for the first time. The yield of the nucleus purified using gwINTACT from transgenic tomato leaves was doubled compared with using a traditional INTACT procedure, accompanied by more than 95% removal of chloroplasts. Relative gene expression of ethylene-related genes with ethylene treatment was reevaluated in gwINTACT leaves to reveal more different results from the traditional gene expression assay based on total RNA. Therefore, establishing the gwINTACT system in this study facilitates the precise deciphering of the transcriptional status in various tomato tissues, which lays the foundation for the further experimental study of nucleus-related molecular regulation on fruit ripening, such as ChIP-seq and ATAC-seq.
Collapse
|
5
|
Barra L, Termolino P, Aiese Cigliano R, Cremona G, Paparo R, Lanzillo C, Consiglio MF, Conicella C. Meiocyte Isolation by INTACT and Meiotic Transcriptome Analysis in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2021; 12:638051. [PMID: 33747019 PMCID: PMC7969724 DOI: 10.3389/fpls.2021.638051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 02/01/2021] [Indexed: 05/06/2023]
Abstract
Isolation of nuclei tagged in specific cell types (INTACT) is a method developed to isolate cell-type-specific nuclei that are tagged through in vivo biotin labeling of a nuclear targeting fusion (NTF) protein. In our work, INTACT was used to capture nuclei of meiocytes and to generate a meiotic transcriptome in Arabidopsis. Using the promoter of AtDMC1 recombinase to label meiotic nuclei, we generated transgenic plants carrying AtDMC1:NTF along with biotin ligase enzyme (BirA) under the constitutive ACTIN2 (ACT2) promoter. AtDMC1-driven expression of biotin-labeled NTF allowed us to collect nuclei of meiocytes by streptavidin-coated magnetic beads. The nuclear meiotic transcriptome was obtained by RNA-seq using low-quantity input RNA. Transcripts grouped into different categories according to their expression levels were investigated by gene ontology enrichment analysis (GOEA). The most enriched GO term "DNA demethylation" in mid/high-expression classes suggests that this biological process is particularly relevant to meiosis onset. The majority of genes with established roles in meiosis were distributed in the classes of mid/high and high expression. Meiotic transcriptome was compared with public available transcriptomes from other tissues in Arabidopsis. Bioinformatics analysis by expression network identified a core of more than 1,500 genes related to meiosis landmarks.
Collapse
Affiliation(s)
- Lucia Barra
- Institute of Biosciences and Bioresources, National Research Council of Italy, Portici, Italy
| | - Pasquale Termolino
- Institute of Biosciences and Bioresources, National Research Council of Italy, Portici, Italy
| | | | - Gaetana Cremona
- Institute of Biosciences and Bioresources, National Research Council of Italy, Portici, Italy
| | - Rosa Paparo
- Institute of Biosciences and Bioresources, National Research Council of Italy, Portici, Italy
| | - Carmine Lanzillo
- Institute of Biosciences and Bioresources, National Research Council of Italy, Portici, Italy
| | | | - Clara Conicella
- Institute of Biosciences and Bioresources, National Research Council of Italy, Portici, Italy
- *Correspondence: Clara Conicella,
| |
Collapse
|
6
|
Palovaara J, Weijers D. Cell Type-Specific Transcriptomics in the Plant Embryo Using an Adapted INTACT Protocol. Methods Mol Biol 2020; 2122:141-150. [PMID: 31975301 DOI: 10.1007/978-1-0716-0342-0_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cells differentiate from undifferentiated precursors in order to establish the tissues of vascular plants. The different cell types and stem cells are first specified in the early embryo. How cell type specification is instructed by transcriptional control on a genome-wide level is poorly understood. A major hurdle has been the technical challenge associated with obtaining cellular transcriptomes in this inaccessible tissue. Recently, we adapted a two-component genetic labeling system called INTACT to isolate nuclei and generate a microarray-based expression atlas of the cell types in the early Arabidopsis thaliana embryo. Here we present a step-by-step description of the adapted INTACT protocol, as well as the approach to generate transcriptomic profiles. This protocol has been adapted to account for using seeds with embryos of various developmental stages as a starting material, and the relatively few cell type-specific nuclei that can be isolated from embryos.
Collapse
Affiliation(s)
| | - Dolf Weijers
- Laboratory of Biochemistry, Wageningen University, Wageningen, The Netherlands
| |
Collapse
|
7
|
Wang HLV, Chekanova JA. An Overview of Methodologies in Studying lncRNAs in the High-Throughput Era: When Acronyms ATTACK! Methods Mol Biol 2019; 1933:1-30. [PMID: 30945176 PMCID: PMC6684206 DOI: 10.1007/978-1-4939-9045-0_1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The discovery of pervasive transcription in eukaryotic genomes provided one of many surprising (and perhaps most surprising) findings of the genomic era and led to the uncovering of a large number of previously unstudied transcriptional events. This pervasive transcription leads to the production of large numbers of noncoding RNAs (ncRNAs) and thus opened the window to study these diverse, abundant transcripts of unclear relevance and unknown function. Since that discovery, recent advances in high-throughput sequencing technologies have identified a large collection of ncRNAs, from microRNAs to long noncoding RNAs (lncRNAs). Subsequent discoveries have shown that many lncRNAs play important roles in various eukaryotic processes; these discoveries have profoundly altered our understanding of the regulation of eukaryotic gene expression. Although the identification of ncRNAs has become a standard experimental approach, the functional characterization of these diverse ncRNAs remains a major challenge. In this chapter, we highlight recent progress in the methods to identify lncRNAs and the techniques to study the molecular function of these lncRNAs and the application of these techniques to the study of plant lncRNAs.
Collapse
Affiliation(s)
- Hsiao-Lin V Wang
- Guangxi Key Laboratory of Sugarcane Biology, Guangxi University, Nanning, Guangxi, China
- Present address: Department of Biology, Emory University, Atlanta, GA, USA
| | - Julia A Chekanova
- Guangxi Key Laboratory of Sugarcane Biology, Guangxi University, Nanning, Guangxi, China.
| |
Collapse
|
8
|
Abstract
With Chromosome Conformation Capture (3C), the relative interaction frequency of one chromosomal fragment with another can be determined. The technique is especially suited for unraveling the 3D organization of specific loci when focusing on aspects such as enhancer-promoter interactions or other topological conformations of the genome. 3C has been extensively used in animal systems, among others providing insight into gene regulation by distant cis-regulatory elements. In recent years, the 3C technique has been applied in plant research. However, the complexity of plant tissues prevents direct application of existing protocols from animals. Here, we describe an adapted protocol suitable for plant tissues, especially Arabidopsis thaliana and Zea mays.
Collapse
Affiliation(s)
- Blaise Weber
- Laboratory of Plant Development and Epigenetics, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Suraj Jamge
- Laboratory of Molecular Biology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Maike Stam
- Laboratory of Plant Development and Epigenetics, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands.
| |
Collapse
|
9
|
Morao AK, Caillieux E, Colot V, Roudier F. Cell Type-Specific Profiling of Chromatin Modifications and Associated Proteins. Methods Mol Biol 2018; 1675:111-130. [PMID: 29052189 DOI: 10.1007/978-1-4939-7318-7_8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Progression of a cell along a differentiation path is characterized by changes in gene expression profiles. Alterations of these transcriptional programs result from cell type-specific transcription factors that act in a dynamic chromatin environment. Understanding the precise contribution of these molecular factors during the differentiation process requires accessing specific cell types within a developing organ. This chapter describes a streamlined and alternative version of INTACT, a method enabling the isolation of specific cell populations by affinity-purification of tagged nuclei and the subsequent analysis of gene expression, transcription factor binding profiles, as well as chromatin state at a genome-wide scale. In particular, modifications of the nuclei isolation, capture, and purification procedures are proposed that improve time scale, yield, and purity. In addition, the combination of different tags enables the analysis of distinct cell populations from a single transgenic line and the subtractive purification of subpopulations of cells, including those for which no specific promoter is available. Finally, we describe a chromatin immunoprecipitation protocol that has been successfully used to profile histone modifications and other chromatin-associated proteins such as RNA Polymerase II in different cell populations of the Arabidopsis root, including the quiescent center of the stem cell niche.
Collapse
Affiliation(s)
- Ana Karina Morao
- Centre National de la Recherche Scientifique (CNRS) UMR8197, Institut de Biologie de l'Ecole Normale Supérieure, Institut National de la Santé et de la Recherche Médicale (INSERM) U1024, Ecole Normale Supérieure, 46 rue d'Ulm, 75230, Paris Cedex 05, France
| | - Erwann Caillieux
- Centre National de la Recherche Scientifique (CNRS) UMR8197, Institut de Biologie de l'Ecole Normale Supérieure, Institut National de la Santé et de la Recherche Médicale (INSERM) U1024, Ecole Normale Supérieure, 46 rue d'Ulm, 75230, Paris Cedex 05, France
| | - Vincent Colot
- Centre National de la Recherche Scientifique (CNRS) UMR8197, Institut de Biologie de l'Ecole Normale Supérieure, Institut National de la Santé et de la Recherche Médicale (INSERM) U1024, Ecole Normale Supérieure, 46 rue d'Ulm, 75230, Paris Cedex 05, France
| | - François Roudier
- Centre National de la Recherche Scientifique (CNRS) UMR8197, Institut de Biologie de l'Ecole Normale Supérieure, Institut National de la Santé et de la Recherche Médicale (INSERM) U1024, Ecole Normale Supérieure, 46 rue d'Ulm, 75230, Paris Cedex 05, France.
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, F-69342, Lyon, France.
| |
Collapse
|
10
|
Foley SW, Gosai SJ, Wang D, Selamoglu N, Sollitti AC, Köster T, Steffen A, Lyons E, Daldal F, Garcia BA, Staiger D, Deal RB, Gregory BD. A Global View of RNA-Protein Interactions Identifies Post-transcriptional Regulators of Root Hair Cell Fate. Dev Cell 2017; 41:204-220.e5. [PMID: 28441533 PMCID: PMC5605909 DOI: 10.1016/j.devcel.2017.03.018] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 02/13/2017] [Accepted: 03/24/2017] [Indexed: 01/22/2023]
Abstract
The Arabidopsis thaliana root epidermis is comprised of two cell types, hair and nonhair cells, which differentiate from the same precursor. Although the transcriptional programs regulating these events are well studied, post-transcriptional factors functioning in this cell fate decision are mostly unknown. Here, we globally identify RNA-protein interactions and RNA secondary structure in hair and nonhair cell nuclei. This analysis reveals distinct structural and protein binding patterns across both transcriptomes, allowing identification of differential RNA binding protein (RBP) recognition sites. Using these sequences, we identify two RBPs that regulate hair cell development. Specifically, we find that SERRATE functions in a microRNA-dependent manner to inhibit hair cell fate, while also terminating growth of root hairs mostly independent of microRNA biogenesis. In addition, we show that GLYCINE-RICH PROTEIN 8 promotes hair cell fate while alleviating phosphate starvation stress. In total, this global analysis reveals post-transcriptional regulators of plant root epidermal cell fate.
Collapse
Affiliation(s)
- Shawn W Foley
- Department of Biology, University of Pennsylvania, 433 South University Avenue, Philadelphia, PA 19104, USA; Cell and Molecular Biology Graduate Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sager J Gosai
- Department of Biology, University of Pennsylvania, 433 South University Avenue, Philadelphia, PA 19104, USA
| | - Dongxue Wang
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | - Nur Selamoglu
- Department of Biology, University of Pennsylvania, 433 South University Avenue, Philadelphia, PA 19104, USA
| | - Amelia C Sollitti
- Department of Biology, University of Pennsylvania, 433 South University Avenue, Philadelphia, PA 19104, USA
| | - Tino Köster
- Department of Molecular Cell Physiology, Faculty of Biology, Bielefeld University, Bielefeld 33615, Germany
| | - Alexander Steffen
- Department of Molecular Cell Physiology, Faculty of Biology, Bielefeld University, Bielefeld 33615, Germany
| | - Eric Lyons
- School of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Fevzi Daldal
- Department of Biology, University of Pennsylvania, 433 South University Avenue, Philadelphia, PA 19104, USA
| | - Benjamin A Garcia
- Epigenetics Program, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Dorothee Staiger
- Department of Molecular Cell Physiology, Faculty of Biology, Bielefeld University, Bielefeld 33615, Germany
| | - Roger B Deal
- Department of Biology, Emory University, Atlanta, GA 30322, USA.
| | - Brian D Gregory
- Department of Biology, University of Pennsylvania, 433 South University Avenue, Philadelphia, PA 19104, USA; Cell and Molecular Biology Graduate Group, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
11
|
Moreno-Romero J, Santos-González J, Hennig L, Köhler C. Applying the INTACT method to purify endosperm nuclei and to generate parental-specific epigenome profiles. Nat Protoc 2017; 12:238-254. [PMID: 28055034 DOI: 10.1038/nprot.2016.167] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The early endosperm tissue of dicot species is very difficult to isolate by manual dissection. This protocol details how to apply the INTACT (isolation of nuclei tagged in specific cell types) system for isolating early endosperm nuclei of Arabidopsis at high purity and how to generate parental-specific epigenome profiles. As a Protocol Extension, this article describes an adaptation of an existing Nature Protocol that details the use of the INTACT method for purification of root nuclei. We address how to obtain the INTACT lines, generate the starting material and purify the nuclei. We describe a method that allows purity assessment, which has not been previously addressed. The purified nuclei can be used for ChIP and DNA bisulfite treatment followed by next-generation sequencing (seq) to study histone modifications and DNA methylation profiles, respectively. By using two different Arabidopsis accessions as parents that differ by a large number of single-nucleotide polymorphisms (SNPs), we were able to distinguish the parental origin of epigenetic modifications. Our protocol describes the only working method to our knowledge for generating parental-specific epigenome profiles of the early Arabidopsis endosperm. The complete protocol, from silique collection to finished libraries, can be completed in 2 d for bisulfite-seq (BS-seq) and 3 to 4 d for ChIP-seq experiments.This protocol is an extension to: Nat. Protoc. 6, 56-68 (2011); doi:10.1038/nprot.2010.175; published online 16 December 2010.
Collapse
Affiliation(s)
- Jordi Moreno-Romero
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Juan Santos-González
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Lars Hennig
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Claudia Köhler
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| |
Collapse
|
12
|
Chitikova Z, Steiner FA. Cell type-specific epigenome profiling using affinity-purified nuclei. Genesis 2016; 54:160-9. [PMID: 26789661 DOI: 10.1002/dvg.22919] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 01/08/2016] [Accepted: 01/14/2016] [Indexed: 11/08/2022]
Abstract
The development of a multicellular organism from a single zygote depends on the differentiation of progenitor cells to specialized cell types. The differentiation of these cell types is associated with changes in gene expression and the underlying chromatin landscape. To understand how these processes are regulated, it is desirable to understand how the chromatin features that constitute the epigenome differ between cell types at any given time during development. INTACT, a method for the cell type-specific purification of nuclei that can be used for the isolation of both RNA and chromatin, has emerged as a powerful tool to simultaneously study gene expression and chromatin profiles specifically in cell types of interest. In this review, we focus on the application of INTACT to different model organisms and discuss its potential for profiling cell types in their developmental context.
Collapse
Affiliation(s)
- Zhanna Chitikova
- Department of Molecular Biology, Sciences III, University of Geneva, Geneva, Switzerland
| | - Florian A Steiner
- Department of Molecular Biology, Sciences III, University of Geneva, Geneva, Switzerland
| |
Collapse
|
13
|
Yan W, Chen D, Kaufmann K. Molecular mechanisms of floral organ specification by MADS domain proteins. CURRENT OPINION IN PLANT BIOLOGY 2016; 29:154-62. [PMID: 26802807 DOI: 10.1016/j.pbi.2015.12.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 11/23/2015] [Accepted: 12/06/2015] [Indexed: 05/11/2023]
Abstract
Flower development is a model system to understand organ specification in plants. The identities of different types of floral organs are specified by homeotic MADS transcription factors that interact in a combinatorial fashion. Systematic identification of DNA-binding sites and target genes of these key regulators show that they have shared and unique sets of target genes. DNA binding by MADS proteins is not based on 'simple' recognition of a specific DNA sequence, but depends on DNA structure and combinatorial interactions. Homeotic MADS proteins regulate gene expression via alternative mechanisms, one of which may be to modulate chromatin structure and accessibility in their target gene promoters.
Collapse
Affiliation(s)
- Wenhao Yan
- Institute for Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany
| | - Dijun Chen
- Institute for Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany
| | - Kerstin Kaufmann
- Institute for Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany.
| |
Collapse
|
14
|
Marquès-Bueno MDM, Morao AK, Cayrel A, Platre MP, Barberon M, Caillieux E, Colot V, Jaillais Y, Roudier F, Vert G. A versatile Multisite Gateway-compatible promoter and transgenic line collection for cell type-specific functional genomics in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 85:320-333. [PMID: 26662936 PMCID: PMC4880041 DOI: 10.1111/tpj.13099] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 11/20/2015] [Accepted: 11/24/2015] [Indexed: 05/03/2023]
Abstract
Multicellular organisms are composed of many cell types that acquire their specific fate through a precisely controlled pattern of gene expression in time and space dictated in part by cell type-specific promoter activity. Understanding the contribution of highly specialized cell types in the development of a whole organism requires the ability to isolate or analyze different cell types separately. We have characterized and validated a large collection of root cell type-specific promoters and have generated cell type-specific marker lines. These benchmarked promoters can be readily used to evaluate cell type-specific complementation of mutant phenotypes, or to knockdown gene expression using targeted expression of artificial miRNA. We also generated vectors and characterized transgenic lines for cell type-specific induction of gene expression and cell type-specific isolation of nuclei for RNA and chromatin profiling. Vectors and seeds from transgenic Arabidopsis plants will be freely available, and will promote rapid progress in cell type-specific functional genomics. We demonstrate the power of this promoter set for analysis of complex biological processes by investigating the contribution of root cell types in the IRT1-dependent root iron uptake. Our findings revealed the complex spatial expression pattern of IRT1 in both root epidermis and phloem companion cells and the requirement for IRT1 to be expressed in both cell types for proper iron homeostasis.
Collapse
Affiliation(s)
- Maria del Mar Marquès-Bueno
- Laboratoire de Reproduction et Développement des Plantes, UMR 5667 CNRS/INRA/ENS-Lyon/Université de Lyon, 46 allée d’Italie, 69364 Lyon Cedex 07, France
| | - Ana Karina Morao
- Institut de Biologie de l'Ecole Normale Supérieure, UMR 8197 CNRS/INSERM, Paris 75005, France
| | - Anne Cayrel
- Institute for Integrative Biology of the Cell, UMR 9198 CNRS/CEA/University Paris-Sud, Avenue de la Terrasse, 91190 Gif-sur-Yvette, France
| | - Matthieu Pierre Platre
- Laboratoire de Reproduction et Développement des Plantes, UMR 5667 CNRS/INRA/ENS-Lyon/Université de Lyon, 46 allée d’Italie, 69364 Lyon Cedex 07, France
| | - Marie Barberon
- University of Lausanne, Department of Plant Molecular Biology, UNIL-Sorge, 1015 Lausanne, Switzerland
| | - Erwann Caillieux
- Institut de Biologie de l'Ecole Normale Supérieure, UMR 8197 CNRS/INSERM, Paris 75005, France
| | - Vincent Colot
- Institut de Biologie de l'Ecole Normale Supérieure, UMR 8197 CNRS/INSERM, Paris 75005, France
| | - Yvon Jaillais
- Laboratoire de Reproduction et Développement des Plantes, UMR 5667 CNRS/INRA/ENS-Lyon/Université de Lyon, 46 allée d’Italie, 69364 Lyon Cedex 07, France
- For correspondence (, , or )
| | - François Roudier
- Institut de Biologie de l'Ecole Normale Supérieure, UMR 8197 CNRS/INSERM, Paris 75005, France
- For correspondence (, , or )
| | - Grégory Vert
- Institute for Integrative Biology of the Cell, UMR 9198 CNRS/CEA/University Paris-Sud, Avenue de la Terrasse, 91190 Gif-sur-Yvette, France
- For correspondence (, , or )
| |
Collapse
|