Research Resource: Genome-Wide Profiling of Progesterone Receptor Binding in the Mouse Uterus

Progesterone (P4) signaling through its nuclear transcription factor, the progesterone receptor (PR), is essential for normal uterine function. Although deregulation of PR-mediated signaling is known to underscore uterine dysfunction and a number of endometrial pathologies, the early molecular mechanisms of this deregulation are unclear. To address this issue, we have defined the genome-wide PR cistrome in the murine uterus using chromatin immunoprecipitation (ChIP) followed by massively parallel sequencing (ChIP-seq). In uteri of ovariectomized mice, we identified 6367 PR-binding sites in the absence of P4 ligand; however, this number increased at nearly 3-fold (18,432) after acute P4 exposure. Sequence analysis revealed that approximately 73% of these binding sites contain a progesterone response element or a half-site motif recognized by the PR. Many previously identified P4 target genes known to regulate uterine function were found to contain PR-binding sites, confirming the validity of our methodology. Interestingly, when the ChIP-seq data were coupled with our microarray expression data, we identified a novel regulatory role for uterine P4 in circadian rhythm gene expression, thereby uncovering a hitherto unexpected new circadian biology for P4 in this tissue. Further mining of the ChIP-seq data revealed Sox17 as a direct transcriptional PR target gene in the uterus. As a member of the Sox transcription factor family, Sox17 represents a potentially novel mediator of PR action in the murine uterus. Collectively, our first line of analysis of the uterine PR cistrome provides the first insights into the early molecular mechanisms that underpin normal uterine responsiveness to acute P4 exposure. Future analysis promises to reveal the PR interactome and, in turn, potential therapeutic targets for the diagnosis and/or treatment of endometrial dysfunction.

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Identification of key tissue-specific, biological processes by integrating enhancer information in maize gene regulatory networks

10.1101/2020.06.16.155481 ◽

2020 ◽

Author(s):

Maud Fagny ◽

Marieke Lydia Kuijjer ◽

Maike Stam ◽

Johann Joets ◽

Olivier Turc ◽

...

Keyword(s):

Gene Expression ◽

Transcription Factor ◽

Binding Sites ◽

Regulatory Network ◽

Tissue Specificity ◽

Target Genes ◽

Specific Gene ◽

Tissue Specific ◽

Genome Wide ◽

Gene Regulatory

AbstractEnhancers are important regulators of gene expression during numerous crucial processes including tissue differentiation across development. In plants, their recent molecular characterization revealed their capacity to activate the expression of several target genes through the binding of transcription factors. Nevertheless, identifying these target genes at a genome-wide level remains a challenge, in particular in species with large genomes, where enhancers and target genes can be hundreds of kilobases away. Therefore, the contribution of enhancers to regulatory network is still poorly understood in plants. In this study, we investigate the enhancer-driven regulatory network of two maize tissues at different stages: leaves at seedling stage and husks (bracts) at flowering. Using a systems biology approach, we integrate genomic, epigenomic and transcriptomic data to model the regulatory relationship between transcription factors and their potential target genes. We identify regulatory modules specific to husk and V2-IST, and show that they are involved in distinct functions related to the biology of each tissue. We evidence enhancers exhibiting binding sites for two distinct transcription factor families (DOF and AP2/ERF) that drive the tissue-specificity of gene expression in seedling immature leaf and husk. Analysis of the corresponding enhancer sequences reveals that two different transposable element families (TIR transposon Mutator and MITE Pif/Harbinger) have shaped the regulatory network in each tissue, and that MITEs have provided new transcription factor binding sites that are involved in husk tissue-specificity.SignificanceEnhancers play a major role in regulating tissue-specific gene expression in higher eukaryotes, including angiosperms. While molecular characterization of enhancers has improved over the past years, identifying their target genes at the genome-wide scale remains challenging. Here, we integrate genomic, epigenomic and transcriptomic data to decipher the tissue-specific gene regulatory network controlled by enhancers at two different stages of maize leaf development. Using a systems biology approach, we identify transcription factor families regulating gene tissue-specific expression in husk and seedling leaves, and characterize the enhancers likely to be involved. We show that a large part of maize enhancers is derived from transposable elements, which can provide novel transcription factor binding sites crucial to the regulation of tissue-specific biological functions.

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Genome Wide Approaches to Identify Protein-DNA Interactions

Current Medicinal Chemistry ◽

10.2174/0929867325666180530115711 ◽

2020 ◽

Vol 26 (42) ◽

pp. 7641-7654 ◽

Cited By ~ 1

Author(s):

Tao Ma ◽

Zhenqing Ye ◽

Liguo Wang

Keyword(s):

Transcription Factor ◽

Binding Sites ◽

Target Genes ◽

Rapid Development ◽

Transcription Factor Binding Sites ◽

Transcription Factor Binding ◽

Computational Approaches ◽

Factor Binding ◽

Genome Wide ◽

Chip Chip

Background: Transcription factors are DNA-binding proteins that play key roles in many fundamental biological processes. Unraveling their interactions with DNA is essential to identify their target genes and understand the regulatory network. Genome-wide identification of their binding sites became feasible thanks to recent progress in experimental and computational approaches. ChIP-chip, ChIP-seq, and ChIP-exo are three widely used techniques to demarcate genome-wide transcription factor binding sites. Objective: This review aims to provide an overview of these three techniques including their experiment procedures, computational approaches, and popular analytic tools. Conclusion: ChIP-chip, ChIP-seq, and ChIP-exo have been the major techniques to study genome- wide in vivo protein-DNA interaction. Due to the rapid development of next-generation sequencing technology, array-based ChIP-chip is deprecated and ChIP-seq has become the most widely used technique to identify transcription factor binding sites in genome-wide. The newly developed ChIP-exo further improves the spatial resolution to single nucleotide. Numerous tools have been developed to analyze ChIP-chip, ChIP-seq and ChIP-exo data. However, different programs may employ different mechanisms or underlying algorithms thus each will inherently include its own set of statistical assumption and bias. So choosing the most appropriate analytic program for a given experiment needs careful considerations. Moreover, most programs only have command line interface so their installation and usage will require basic computation expertise in Unix/Linux.

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Epigenetic control of hematopoiesis: the PU.1 chromatin connection

Biological Chemistry ◽

10.1515/hsz-2014-0195 ◽

2014 ◽

Vol 395 (11) ◽

pp. 1265-1274 ◽

Cited By ~ 27

Author(s):

Boet van Riel ◽

Frank Rosenbauer

Keyword(s):

Transcription Factor ◽

Transcription Factors ◽

Molecular Mechanisms ◽

Target Genes ◽

Current Knowledge ◽

Dna Methyltransferases ◽

Chromatin Remodelers ◽

Cell Lineages ◽

Protein Partners ◽

Genome Wide

Abstract Purine-rich box1 (PU.1) is a transcription factor that not only has a key role in the development of most hematopoietic cell lineages but also in the suppression of leukemia. To exert these functions, PU.1 can cross-talk with multiple different proteins by forming complexes in order to activate or repress transcription. Among its protein partners are chromatin remodelers, DNA methyltransferases, and a number of other transcription factors with important roles in hematopoiesis. While a great deal of knowledge has been acquired about PU.1 function over the years, it was the development of novel genome-wide technologies, which boosted our understanding of how PU.1 acts on the chromatin to drive its repertoire of target genes. This review summarizes current knowledge and ideas of molecular mechanisms by which PU.1 controls hematopoiesis and suppresses leukemia.

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The Scleraxis Transcription Factor Directly Regulates Multiple Distinct Molecular and Cellular Processes During Early Tendon Cell Differentiation

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.654397 ◽

2021 ◽

Vol 9 ◽

Author(s):

Han Liu ◽

Jingyue Xu ◽

Yu Lan ◽

Hee-Woong Lim ◽

Rulang Jiang

Keyword(s):

Transcription Factor ◽

Cell Differentiation ◽

Molecular Mechanisms ◽

Target Genes ◽

Rna Seq ◽

Tendon Cell ◽

Tendon Development ◽

Genome Wide ◽

Direct Target ◽

Embryonic Tendon

Proper development of tendons is crucial for the integration and function of the musculoskeletal system. Currently little is known about the molecular mechanisms controlling tendon development and tendon cell differentiation. The transcription factor Scleraxis (Scx) is expressed throughout tendon development and plays essential roles in both embryonic tendon development and adult tendon healing, but few direct target genes of Scx in tendon development have been reported and genome-wide identification of Scx direct target genes in vivo has been lacking. In this study, we have generated a ScxFlag knockin mouse strain, which produces fully functional endogenous Scx proteins containing a 2xFLAG epitope tag at the carboxy terminus. We mapped the genome-wide Scx binding sites in the developing limb tendon tissues, identifying 12,097 high quality Scx regulatory cis-elements in-around 7,520 genes. Comparative analysis with previously reported embryonic tendon cell RNA-seq data identified 490 candidate Scx direct target genes in early tendon development. Furthermore, we characterized a new Scx gene-knockout mouse line and performed whole transcriptome RNA sequencing analysis of E15.5 forelimb tendon cells from Scx–/– embryos and control littermates, identifying 68 genes whose expression in the developing tendon tissues significantly depended on Scx function. Combined analysis of the ChIP-seq and RNA-seq data yielded 32 direct target genes that required Scx for activation and an additional 17 target genes whose expression was suppressed by Scx during early tendon development. We further analyzed and validated Scx-dependent tendon-specific expression patterns of a subset of the target genes, including Fmod, Kera, Htra3, Ssc5d, Tnmd, and Zfp185, by in situ hybridization and real-time quantitative polymerase chain reaction assays. These results provide novel insights into the molecular mechanisms mediating Scx function in tendon development and homeostasis. The ChIP-seq and RNA-seq data provide a rich resource for aiding design of further studies of the mechanisms regulating tendon cell differentiation and tendon tissue regeneration. The ScxFlag mice provide a valuable new tool for unraveling the molecular mechanisms involving Scx in the protein interaction and gene-regulatory networks underlying many developmental and disease processes.

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Genome-wide strategies reveal target genes of Npas4l associated with cardiovascular development in zebrafish

10.1101/461988 ◽

2018 ◽

Cited By ~ 1

Author(s):

Michele Marass ◽

Arica Beisaw ◽

Claudia Gerri ◽

Francesca Luzzani ◽

Nana Fukuda ◽

...

Keyword(s):

Transcription Factor ◽

Chromatin Immunoprecipitation ◽

Molecular Mechanisms ◽

Target Genes ◽

Building Blocks ◽

Phenotypic Characterization ◽

Cardiovascular Development ◽

Genome Wide ◽

Transcription Factor Genes

ABSTRACTThe development of a vascular network is essential to nourish tissues and sustain organ function throughout life. Endothelial cells (ECs) are the building blocks of blood vessels, yet our understanding of EC specification remains incomplete. zebrafish cloche/npas4l mutants have been used broadly as an avascular model, but little is known about the molecular mechanisms of action of the Npas4l transcription factor. Here, to identify its direct and indirect target genes, we combined complementary genome-wide approaches including transcriptome analyses and chromatin immunoprecipitation (ChIP). The cross-analysis of these datasets indicates that Npas4l functions as a master regulator by directly inducing a group of transcription factor genes crucial for hematoendothelial specification such as etv2, tal1 and lmo2. We also identified new targets of Npas4l and investigated the function of a subset of them using the CRISPR/Cas9 technology. Phenotypic characterization of tspan18b mutants reveals a novel player in developmental angiogenesis, confirming the reliability of the datasets generated. Collectively, these data represent a useful resource for future studies aimed to better understand EC fate determination and vascular development.

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