scholarly journals Genome-Wide STAT3 Binding Analysis after Histone Deacetylase Inhibition Reveals Novel Target Genes in Dendritic Cells

2016 ◽  
Vol 9 (2) ◽  
pp. 126-144 ◽  
Author(s):  
Yaping Sun ◽  
Matthew Iyer ◽  
Richard McEachin ◽  
Meng Zhao ◽  
Yi-Mi Wu ◽  
...  

STAT3 is a master transcriptional regulator that plays an important role in the induction of both immune activation and immune tolerance in dendritic cells (DCs). The transcriptional targets of STAT3 in promoting DC activation are becoming increasingly understood; however, the mechanisms underpinning its role in causing DC suppression remain largely unknown. To determine the functional gene targets of STAT3, we compared the genome-wide binding of STAT3 using ChIP sequencing coupled with gene expression microarrays to determine STAT3-dependent gene regulation in DCs after histone deacetylase (HDAC) inhibition. HDAC inhibition boosted the ability of STAT3 to bind to distinct DNA targets and regulate gene expression. Among the top 500 STAT3 binding sites, the frequency of canonical motifs was significantly higher than that of noncanonical motifs. Functional analysis revealed that after treatment with an HDAC inhibitor, the upregulated STAT3 target genes were those that were primarily the negative regulators of proinflammatory cytokines and those in the IL-10 signaling pathway. The downregulated STAT3-dependent targets were those involved in immune effector processes and antigen processing/presentation. The expression and functional relevance of these genes were validated. Specifically, functional studies confirmed that the upregulation of IL-10Ra by STAT3 contributed to the suppressive function of DCs following HDAC inhibition.

2015 ◽  
Vol 227 (2) ◽  
pp. 83-92 ◽  
Author(s):  
Praveen Kumar ◽  
Vishwa Mohan ◽  
Rohit Anthony Sinha ◽  
Megha Chagtoo ◽  
Madan M Godbole

Thyroid hormone (TH) through its receptor (TRα/β) influences spatio-temporal regulation of its target gene repertoire during brain development. Though hypothyroidism in WT rodent models of perinatal hypothyroidism severely impairs neurodevelopment, its effect on TRα/β knockout mice is less severe. An explanation to this paradox is attributed to a possible repressive action of unliganded TRs during development. Since unliganded TRs suppress gene expression through the recruitment of histone deacetylase (HDACs) via co-repressor complexes, we tested whether pharmacological inhibition of HDACs may prevent the effects of hypothyroidism on brain development. Using valproate, an HDAC inhibitor, we show that HDAC inhibition significantly blocks the deleterious effects of hypothyroidism on rat cerebellum, evident by recovery of TH target genes likeBdnf,Pcp2andMbpas well as improved dendritic structure of cerebellar Purkinje neurons. Together with this, HDAC inhibition also rescues hypothyroidism-induced motor and cognitive defects. This study therefore provides an insight into the role of HDACs in TH insufficiency during neurodevelopment and their inhibition as a possible therapeutics for treatment.


Endocrinology ◽  
2018 ◽  
Vol 160 (1) ◽  
pp. 38-54 ◽  
Author(s):  
Keiichi Itoi ◽  
Ikuko Motoike ◽  
Ying Liu ◽  
Sam Clokie ◽  
Yasumasa Iwasaki ◽  
...  

Abstract Glucocorticoids (GCs) are essential for stress adaptation, acting centrally and in the periphery. Corticotropin-releasing factor (CRF), a major regulator of adrenal GC synthesis, is produced in the paraventricular nucleus of the hypothalamus (PVH), which contains multiple neuroendocrine and preautonomic neurons. GCs may be involved in diverse regulatory mechanisms in the PVH, but the target genes of GCs are largely unexplored except for the CRF gene (Crh), a well-known target for GC negative feedback. Using a genome-wide RNA-sequencing analysis, we identified transcripts that changed in response to either high-dose corticosterone (Cort) exposure for 12 days (12-day high Cort), corticoid deprivation for 7 days (7-day ADX), or acute Cort administration. Among others, canonical GC target genes were upregulated prominently by 12-day high Cort. Crh was upregulated or downregulated most prominently by either 7-day ADX or 12-day high Cort, emphasizing the recognized feedback effects of GC on the hypothalamic-pituitary-adrenal (HPA) axis. Concomitant changes in vasopressin and apelin receptor gene expression are likely to contribute to HPA repression. In keeping with the pleotropic cellular actions of GCs, 7-day ADX downregulated numerous genes of a broad functional spectrum. The transcriptome response signature differed markedly between acute Cort injection and 12-day high Cort. Remarkably, six immediate early genes were upregulated 1 hour after Cort injection, which was confirmed by quantitative reverse transcription PCR and semiquantitative in situ hybridization. This study may provide a useful database for studying the regulatory mechanisms of GC-dependent gene expression and repression in the PVH.


2020 ◽  
Author(s):  
SK Reilly ◽  
SJ Gosai ◽  
A Gutierrez ◽  
JC Ulirsch ◽  
M Kanai ◽  
...  

AbstractCRISPR screens for cis-regulatory elements (CREs) have shown unprecedented power to endogenously characterize the non-coding genome. To characterize CREs we developed HCR-FlowFISH (Hybridization Chain Reaction Fluorescent In-Situ Hybridization coupled with Flow Cytometry), which directly quantifies native transcripts within their endogenous loci following CRISPR perturbations of regulatory elements, eliminating the need for restrictive phenotypic assays such as growth or transcript-tagging. HCR-FlowFISH accurately quantifies gene expression across a wide range of transcript levels and cell types. We also developed CASA (CRISPR Activity Screen Analysis), a hierarchical Bayesian model to identify and quantify CRE activity. Using >270,000 perturbations, we identified CREs for GATA1, HDAC6, ERP29, LMO2, MEF2C, CD164, NMU, FEN1 and the FADS gene cluster. Our methods detect subtle gene expression changes and identify CREs regulating multiple genes, sometimes at different magnitudes and directions. We demonstrate the power of HCR-FlowFISH to parse genome-wide association signals by nominating causal variants and target genes.


2021 ◽  
Vol 53 (9) ◽  
pp. 1290-1299
Author(s):  
Nurlan Kerimov ◽  
James D. Hayhurst ◽  
Kateryna Peikova ◽  
Jonathan R. Manning ◽  
Peter Walter ◽  
...  

AbstractMany gene expression quantitative trait locus (eQTL) studies have published their summary statistics, which can be used to gain insight into complex human traits by downstream analyses, such as fine mapping and co-localization. However, technical differences between these datasets are a barrier to their widespread use. Consequently, target genes for most genome-wide association study (GWAS) signals have still not been identified. In the present study, we present the eQTL Catalogue (https://www.ebi.ac.uk/eqtl), a resource of quality-controlled, uniformly re-computed gene expression and splicing QTLs from 21 studies. We find that, for matching cell types and tissues, the eQTL effect sizes are highly reproducible between studies. Although most QTLs were shared between most bulk tissues, we identified a greater diversity of cell-type-specific QTLs from purified cell types, a subset of which also manifested as new disease co-localizations. Our summary statistics are freely available to enable the systematic interpretation of human GWAS associations across many cell types and tissues.


2020 ◽  
Vol 295 (13) ◽  
pp. 4212-4223 ◽  
Author(s):  
Chun Guo ◽  
Jian Li ◽  
Nickolas Steinauer ◽  
Madeline Wong ◽  
Brent Wu ◽  
...  

In up to 15% of acute myeloid leukemias (AMLs), a recurring chromosomal translocation, termed t(8;21), generates the AML1–eight–twenty-one (ETO) leukemia fusion protein, which contains the DNA-binding domain of Runt-related transcription factor 1 (RUNX1) and almost all of ETO. RUNX1 and the AML1–ETO fusion protein are coexpressed in t(8;21) AML cells and antagonize each other's gene-regulatory functions. AML1–ETO represses transcription of RUNX1 target genes by competitively displacing RUNX1 and recruiting corepressors such as histone deacetylase 3 (HDAC3). Recent studies have shown that AML1–ETO and RUNX1 co-occupy the binding sites of AML1–ETO–activated genes. How this joined binding allows RUNX1 to antagonize AML1–ETO–mediated transcriptional activation is unclear. Here we show that RUNX1 functions as a bona fide repressor of transcription activated by AML1–ETO. Mechanistically, we show that RUNX1 is a component of the HDAC3 corepressor complex and that HDAC3 preferentially binds to RUNX1 rather than to AML1–ETO in t(8;21) AML cells. Studying the regulation of interleukin-8 (IL8), a newly identified AML1–ETO–activated gene, we demonstrate that RUNX1 and HDAC3 collaboratively repress AML1–ETO–dependent transcription, a finding further supported by results of genome-wide analyses of AML1–ETO–activated genes. These and other results from the genome-wide studies also have important implications for the mechanistic understanding of gene-specific coactivator and corepressor functions across the AML1–ETO/RUNX1 cistrome.


2013 ◽  
Vol 368 (1632) ◽  
pp. 20130022 ◽  
Author(s):  
Noboru Jo Sakabe ◽  
Marcelo A. Nobrega

The complex expression patterns observed for many genes are often regulated by distal transcription enhancers. Changes in the nucleotide sequences of enhancers may therefore lead to changes in gene expression, representing a central mechanism by which organisms evolve. With the development of the experimental technique of chromatin immunoprecipitation (ChIP), in which discrete regions of the genome bound by specific proteins can be identified, it is now possible to identify transcription factor binding events (putative cis -regulatory elements) in entire genomes. Comparing protein–DNA binding maps allows us, for the first time, to attempt to identify regulatory differences and infer global patterns of change in gene expression across species. Here, we review studies that used genome-wide ChIP to study the evolution of enhancers. The trend is one of high divergence of cis -regulatory elements between species, possibly compensated by extensive creation and loss of regulatory elements and rewiring of their target genes. We speculate on the meaning of the differences observed and discuss that although ChIP experiments identify the biochemical event of protein–DNA interaction, it cannot determine whether the event results in a biological function, and therefore more studies are required to establish the effect of divergence of binding events on species-specific gene expression.


Blood ◽  
2000 ◽  
Vol 96 (6) ◽  
pp. 2206-2214 ◽  
Author(s):  
Shin-ichi Hashimoto ◽  
Takuji Suzuki ◽  
Shigenori Nagai ◽  
Taro Yamashita ◽  
Nobuaki Toyoda ◽  
...  

Dendritic cells (DCs) are professional antigen-presenting cells in the immune system and can be generated in vitro from hematopoietic progenitor cells, DC precursors, and monocytes in peripheral blood. Serial analysis of gene expression (SAGE) was conducted in lipopolysaccharide (LPS)-stimulated mature and activated DCs (MADCs) derived from human blood monocytes. A total of 31 837 tag sequences from an MADC cDNA library represented 10 962 different genes, and these data were compared with SAGE data for monocyte-derived immature DCs (IMDCs). Many of the genes, such as germinal center kinase–related protein kinase, cystatin F, interferon (IFN)-α–inducible protein p27, EBI3, HEM45, actin-bundling protein, ELC, DC-LAMP, serine/threonine kinase 4, and several genes in expressed sequence tags, were differentially expressed in MADCs, and those encode proteins related to cell structure, antigen-processing enzymes, chemokines, and IFN-inducible proteins. The profile of MADCs was also compared with that of LPS-stimulated monocytes. The Epstein-Barr virus–induced gene 3 and IFN-α–inducible protein p27 are newly identified to be specifically and highly expressed in MADCs, but not in LPS-stimulated monocytes. The comprehensive identification of specific genes expressed in human IMDCs and MADCs should provide candidate genes to define heterogeneous subsets as well as the function and maturation stage of DCs.


2008 ◽  
Vol 76 (4) ◽  
pp. 1581-1589 ◽  
Author(s):  
P. Lupo ◽  
Y. C. Chang ◽  
B. L. Kelsall ◽  
J. M. Farber ◽  
D. Pietrella ◽  
...  

ABSTRACT The aim of this investigation was to study the effect of polysaccharide capsule on the gene expression in dendritic cells (DC) during their interaction with Cryptococcus neoformans. To this end, we used an encapsulated virulent strain of C. neoformans and a cap59 gene-disrupted acapsular avirulent strain derived from the same genetic background. DC were exposed to encapsulated and acapsular C. neoformans strains for 4 h and 18 h, and their transcriptional profiles were analyzed using the Affymetrix mouse gene chip U74Av2. A large number of DC genes were up-regulated after treatment with the acapsular strain. In particular, we observed the up-regulation of the genes involved in DC maturation, such as cell surface receptors, cytokines, and chemokines (interleukin-12 [IL-12], IL-2, IL-1α, IL-1β, IL-6, IL-10, tumor necrosis factor alpha, CCR7, CCL17, CCL22, CCL3, CCL4, CCL7, and CXCL10), membrane proteins, and the genes involved in antigen processing and presentation as well as cell cycle or apoptosis. The chemokine gene expression data were confirmed by real-time reverse transcription-PCR, while the expression of cytokine genes was correlated with their secretion. A completely different pattern of gene expression was observed for DC treated with an encapsulated strain of C. neoformans. In particular, no significant induction was observed in the expression of the genes mentioned above. Moreover, a number of genes, such as those coding for chemokines, were down-regulated. These results suggest that the polysaccharide capsule shrouding the cell wall of C. neoformans plays a fundamental role in inducing DC response, highlighting the molecular basis of the true nature of immune silencing exerted by capsular material.


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