scholarly journals Genome-wide analysis of STAT3 binding in vivo predicts effectors of the anti-inflammatory response in macrophages

Blood ◽  
2012 ◽  
Vol 119 (13) ◽  
pp. e110-e119 ◽  
Author(s):  
Andrew Paul Hutchins ◽  
Stéphane Poulain ◽  
Diego Miranda-Saavedra

Abstract Inflammation is a powerful response of the immune system against invading pathogens, and must be cancelled when unneeded or otherwise death inevitably follows. In macrophages, the anti-inflammatory response (AIR) is driven by STAT3 upon IL-10 signaling. The role of STAT3 is to stimulate the expression of specific genes that in-turn suppress the transcription of proinflammatory genes. Here we describe a systematic approach to identify the elusive STAT3-controlled effectors of the AIR. In vivo STAT3-binding sites were identified by ChIP-seq, coupled to expression analysis by RNA-seq, both in resting and IL-10–treated peritoneal macrophages. We report the genomic targets of STAT3 and show that STAT3's transcriptional program during the AIR is highly specific to IL-10–stimulated macrophages, that STAT3 is a positive transcriptional regulator, and we predict severalputative AIR factors that merit further investigation. This is the first in-depth study of the AIR by next-generation sequencing and provides an unprecedented degree of detail into this fundamental physiologic response.

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Yiyi Jin ◽  
Jianchang Qian ◽  
Xin Ju ◽  
Xiaodong Bao ◽  
Li Li ◽  
...  

Inflammation is a key factor in the pathogenesis of ALI. Therefore, suppression of inflammatory response could be a potential strategy to treat LPS-induced lung injury. Osthole, a natural coumarin extract, has been reported to protect against acute kidney injury through an anti-inflammatory mechanism, but its effect on ALI is poorly understood. In this study, we investigated whether osthole ameliorates inflammatory sepsis-related ALI. Results from in vitro studies indicated that osthole treatment inhibited the LPS-induced inflammatory response in mouse peritoneal macrophages through blocking the nuclear translocation of NF-κB. Consistently, the in vivo studies indicated that osthole significantly prolonged the survival of septic mice which was accompanied by inflammation suppression. In the ALI mouse model, osthole effectively inhibited the development of lung tissue injury, leukocytic recruitment, and cytokine productions, which was associated with inhibition of NF-κB nuclear translocation. These findings provide evidence that osthole was a potent inhibitor of NF-κB and inflammatory injury and suggest that it could be a promising anti-inflammatory agent for therapy of septic shock and acute lung injury.


2020 ◽  
pp. jbc.RA120.015876
Author(s):  
Yating Wang ◽  
Liming Hou ◽  
M. Behfar Ardehali ◽  
Robert E. Kingston ◽  
Brian D Dynlacht

Elongin is an RNA polymerase II (RNAPII)-associated factor that has been shown to stimulate transcriptional elongation in vitro. The Elongin complex is thought to be required for transcriptional induction in response to cellular stimuli and to ubiquitinate RNAPII in response to DNA damage. Yet the impact of the Elongin complex on transcription in vivo has not been well studied. Here, we performed comprehensive studies of the role of Elongin A, the largest subunit of the Elongin complex, on RNAPII transcription genome-wide. Our results suggest that Elongin A localizes to actively transcribed regions and potential enhancers, and the level of recruitment correlated with transcription levels. We also identified a large group of factors involved in transcription as Elongin A-associated factors. In addition, we found that loss of Elongin A leads to dramatically reduced levels of Ser2-phosphorylated, but not total, RNAPII, and cells depleted of Elongin A show stronger promoter RNAPII pausing, suggesting that Elongin A may be involved in the release of paused RNAPII. Our RNA-seq studies suggest that loss of Elongin A did not alter global transcription, and unlike prior in vitro studies, we did not observe a dramatic impact on RNAPII elongation rates in our cell-based nascent RNA-seq experiments upon Elongin A depletion. Taken together, our studies provide the first comprehensive analysis of the role of Elongin A in regulating transcription in vivo. Our studies also revealed that unlike prior in vitro findings, depletion of Elongin A has little impact on global transcription profiles and transcription elongation in vivo.


Genetics ◽  
2021 ◽  
Author(s):  
Krishnaprasad G Nandanan ◽  
Sagar Salim ◽  
Ajith V Pankajam ◽  
Miki Shinohara ◽  
Gen Lin ◽  
...  

Abstract In the baker’s yeast Saccharomyces cerevisiae, most of the meiotic crossovers are generated through a pathway involving the highly conserved mismatch repair related Msh4-Msh5 complex. To understand the role of Msh4-Msh5 in meiotic crossing over, we determined its genome wide in vivo binding sites in meiotic cells. We show that Msh5 specifically associates with DSB hotspots, chromosome axes, and centromeres on chromosomes. A basal level of Msh5 association with these chromosomal features is observed even in the absence of DSB formation (spo11Δ mutant) at the early stages of meiosis. But efficient binding to DSB hotspots and chromosome axes requires DSB formation and resection and is enhanced by double Holliday junction structures. Msh5 binding is also correlated to DSB frequency and enhanced on small chromosomes with higher DSB and crossover density. The axis protein Red1 is required for Msh5 association with the chromosome axes and DSB hotspots but not centromeres. Although binding sites of Msh5 and other pro-crossover factors like Zip3 show extensive overlap, Msh5 associates with centromeres independent of Zip3. These results on Msh5 localization in wild type and meiotic mutants have implications for how Msh4-Msh5 works with other pro-crossover factors to ensure crossover formation.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4329-4329
Author(s):  
Valentina S Caputo ◽  
Nikolaos Trasanidis ◽  
Xiaolin Xiao ◽  
Mark E Robinson ◽  
Alexia Katsarou ◽  
...  

BACKGROUND: Bone disease, a common source of morbidity in multiple myeloma (MM), is caused by RANKL-induced aberrant activation of osteoclasts (OC). RANKL-induced OC lineage commitment requires repression of an Irf-8 dependent macrophage inflammatory transcriptional programme commensurate with activation of an OC lineage-specific programme. Functional data have shown the requirement for the histone acetylation readers Brd2-4 BET proteins and of cMyc for OC lineage development. However, how Brd2-4 and Myc co-operate genome-wide to regulate transcriptome changes that underpin the very early stages of RANKL-induced OC lineage commitment has not been defined. METHODS: The OC progenitor-like murine RAW264.7 cell line was used for osteoclastogenesis. OC were assayed by TRAP staining. We performed RNA-seq for transcriptome analysis and ChIP-seq against Brd2-4, cMyc, and H3K27Ac mark for epigenomic profiling. The pan-Bet inhibitor IBET151 was used alone or in combination with RANKL. ChIP-seq/RNA-seq data were processed using standard bioinformatics pipelines; downstream analyses (pathway and motif enrichment, factor differential binding) were performed by various tools including EnrichR, R packages ChIPpeakAnno/DiffBind, Rose. RESULTS: Transcriptomic profiling of OC progenitors at 0, 4, 14 and 24h post-RANKL treatment identified 12 distinct clusters of expression trends. The 4h activated cluster includes OC master transcription factors (TFs; cMyc, Nfatc1, Fosl), and is enriched in OC-defining pathways. Notably, by 14h the majority of the genes required for mature OC formation and activation are already highly expressed (e.g. Ctsk, Mmp9). The downregulated clusters include monocyte defining TFs (e.g. Irf8, Mafb and Bcl6). These RANKL-dependent transcriptome changes are completely abrogated by iBET151, highlighting the critical role of Brd2-4 in osteoclastogenesis. Differential chromatin binding analysis upon RANKL induction revealed an overall enhanced Brd2-4 binding at already existing or de novo gained sites. This was more pronounced for Brd2&4 and much less for Brd3, with differentially binding sites (DBS) comprising 50% and 20% respectively of all binding sites in RANKL-treated cells. For Brd2&3, DBS were primarily distributed at promoters and for Brd4 at intergenic, candidate enhancers regions. Notably, nearly all gained DBS were sensitive to and abrogated by iBET151. Combinatorial profiling of Brd2 and Brd4 showed that almost half of Brd2 DBS peaks overlap with Brd4 (47%; 897/1896), while only 24% (766/3234) of Brd4 DBS peaks are co-occupied by Brd2. Transcriptome and Brd2&4 DBS integration in combination with motif enrichment analysis, identified genes that are predicted to be regulated by Brd2 and/or Brd4. EnrichR analysis suggests that enhanced binding of Brd2&4, singly or in combination, is required for activation of the critical OC lineage-specific and repression of the macrophage-defining transcriptional programs highlighting the non-redundant roles of Brd2&4 in OC development. Cell lineage commitment often requires 'commissioning' of cell-specific super-enhancers (SE). Combined analysis of genome-wide Brd4/H3K27ac profiles identified 678 RANKL-induced SE and their respective target genes. Further, 110 of these SE showed enhanced Brd4 binding in 2 peaks: 20/110 were linked to significantly up- and 90/100 to down-regulated genes. The repressed genes were significantly enriched to previously described Irf8, MafB and RunX1 targets, suggesting a critical role of SE in the repression of the monocyte/macrophage inflammatory programme during OC lineage commitment. Strikingly, among top hits, we detected a SE linked to the regulation of cMyc. To further investigate its role in OC development, we obtained the cistrome of cMyc after RANKL induction. We identified 560 binding sites which were highly enriched in cMyc, Max, Fli1, Fosl2 and Irf8 motifs. Cistrome-transcriptome integration suggested direct activation of 141 and repression of 52 genes by cMyc in response to RANKL; these are enriched in ribosome biogenesis pathways and Irf8-dependent targets respectively. CONCLUSIONS: Myc and Brd4 mark SE that repress an Irf8-dependent transcriptional programme, a requirement for OC lineage commitment. The non-redundant roles of Brd2&4 suggest that selective targeting of either could inhibit aberrant OC activation associated with MM. Disclosures Caputo: GSK: Research Funding. Auner:Amgen: Other: Consultancy and Research Funding; Takeda: Consultancy; Karyopharm: Consultancy. Karadimitris:GSK: Research Funding.


2020 ◽  
Author(s):  
Elena M Cornejo Castro ◽  
Vickie Marshall ◽  
Justin Lack ◽  
Kathryn Lurain ◽  
Taina Immonen ◽  
...  

Abstract Kaposi sarcoma herpesvirus (KSHV) is the etiological agent of three malignancies, Kaposi sarcoma, primary effusion lymphoma and KSHV-associated multicentric Castelman disease. KSHV infected patients may also have an interleukin six-related KSHV-associated inflammatory cytokine syndrome. KSHV-associated diseases occur in only a minority of chronically KSHV-infected individuals and often in the setting of immunosuppression. Mechanisms by which KSHV genomic variations and systemic co-infections may affect the pathogenic pathways potentially leading to these diseases have not been well characterized in vivo. To date, the majority of comparative genetic analyses of KSHV have been focused on a few regions scattered across the viral genome. We used next-generation sequencing techniques to investigate the taxonomic groupings of viruses from malignant effusion samples from fourteen participants with advanced KSHV-related malignancies, including twelve with primary effusion lymphoma and two with Kaposi sarcoma and elevated KSHV viral load in effusions. The genomic diversity and evolutionary characteristics of nine isolated, near full-length KSHV genomes revealed extensive evidence of mosaic patterns across all these genomes. Further, our comprehensive NGS analysis allowed the identification of two distinct KSHV genome sequences in one individual, consistent with a dual infection. Overall, our results provide significant evidence for the contribution of KSHV phylogenomics to the origin of KSHV subtypes. This report points to a wider scope of studies to establish genome-wide patterns of sequence diversity and define the possible pathogenic role of sequence variations in KSHV-infected individuals.


2021 ◽  
Vol 22 (3) ◽  
pp. 1375
Author(s):  
María Carmen Carceller ◽  
María Isabel Guillén ◽  
María Luisa Gil ◽  
María José Alcaraz

Adipose tissue represents an abundant source of mesenchymal stem cells (MSC) for therapeutic purposes. Previous studies have demonstrated the anti-inflammatory potential of adipose tissue-derived MSC (ASC). Extracellular vesicles (EV) present in the conditioned medium (CM) have been shown to mediate the cytoprotective effects of human ASC secretome. Nevertheless, the role of EV in the anti-inflammatory effects of mouse-derived ASC is not known. The current study has investigated the influence of mouse-derived ASC CM and its fractions on the response of mouse-derived peritoneal macrophages against lipopolysaccharide (LPS). CM and its soluble fraction reduced the release of pro-inflammatory cytokines, adenosine triphosphate and nitric oxide in stimulated cells. They also enhanced the migration of neutrophils or monocytes, in the absence or presence of LPS, respectively, which is likely related to the presence of chemokines, and reduced the phagocytic response. The anti-inflammatory effect of CM may be dependent on the regulation of toll-like receptor 4 expression and nuclear factor-κB activation. Our results demonstrate the anti-inflammatory effects of mouse-derived ASC secretome in mouse-derived peritoneal macrophages stimulated with LPS and show that they are not mediated by EV.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Christian Secchi ◽  
Paola Benaglio ◽  
Francesca Mulas ◽  
Martina Belli ◽  
Dwayne Stupack ◽  
...  

Abstract Background Adult granulosa cell tumor (aGCT) is a rare type of stromal cell malignant cancer of the ovary characterized by elevated estrogen levels. aGCTs ubiquitously harbor a somatic mutation in FOXL2 gene, Cys134Trp (c.402C < G); however, the general molecular effect of this mutation and its putative pathogenic role in aGCT tumorigenesis is not completely understood. We previously studied the role of FOXL2C134W, its partner SMAD3 and its antagonist FOXO1 in cellular models of aGCT. Methods In this work, seeking more comprehensive profiling of FOXL2C134W transcriptomic effects, we performed an RNA-seq analysis comparing the effect of FOXL2WT/SMAD3 and FOXL2C134W/SMAD3 overexpression in an established human GC line (HGrC1), which is not luteinized, and bears normal alleles of FOXL2. Results Our data shows that FOXL2C134W/SMAD3 overexpression alters the expression of 717 genes. These genes include known and novel FOXL2 targets (TGFB2, SMARCA4, HSPG2, MKI67, NFKBIA) and are enriched for neoplastic pathways (Proteoglycans in Cancer, Chromatin remodeling, Apoptosis, Tissue Morphogenesis, Tyrosine Kinase Receptors). We additionally expressed the FOXL2 antagonistic Forkhead protein, FOXO1. Surprisingly, overexpression of FOXO1 mitigated 40% of the altered genome-wide effects specifically related to FOXL2C134W, suggesting it can be a new target for aGCT treatment. Conclusions Our transcriptomic data provide novel insights into potential genes (FOXO1 regulated) that could be used as biomarkers of efficacy in aGCT patients.


2021 ◽  
Vol 22 (3) ◽  
pp. 1347
Author(s):  
Anaïs Amend ◽  
Natalie Wickli ◽  
Anna-Lena Schäfer ◽  
Dalina T. L. Sprenger ◽  
Rudolf A. Manz ◽  
...  

As a key anti-inflammatory cytokine, IL-10 is crucial in preventing inflammatory and autoimmune diseases. However, in human and murine lupus, its role remains controversial. Our aim was to understand regulation and immunologic effects of IL-10 on different immune functions in the setting of lupus. This was explored in lupus-prone NZB/W F1 mice in vitro and vivo to understand IL-10 effects on individual immune cells as well as in the complex in vivo setting. We found pleiotropic IL-10 expression that largely increased with progressing lupus, while IL-10 receptor (IL-10R) levels remained relatively stable. In vitro experiments revealed pro- and anti-inflammatory IL-10 effects. Particularly, IL-10 decreased pro-inflammatory cytokines and slowed B cell proliferation, thereby triggering plasma cell differentiation. The frequent co-expression of ICOS, IL-21 and cMAF suggests that IL-10-producing CD4 T cells are important B cell helpers in this context. In vitro and in vivo effects of IL-10 were not fully concordant. In vivo IL-10R blockade slightly accelerated clinical lupus manifestations and immune dysregulation. Altogether, our side-by-side in vitro and in vivo comparison of the influence of IL-10 on different aspects of immunity shows that IL-10 has dual effects. Our results further reveal that the overall outcome may depend on the interplay of different factors such as target cell, inflammatory and stimulatory microenvironment, disease model and state. A comprehensive understanding of such influences is important to exploit IL-10 as a therapeutic target.


2001 ◽  
Vol 21 (23) ◽  
pp. 8117-8128 ◽  
Author(s):  
Simona Grossi ◽  
Alessandro Bianchi ◽  
Pascal Damay ◽  
David Shore

ABSTRACT Rap1p, the major telomere repeat binding protein in yeast, has been implicated in both de novo telomere formation and telomere length regulation. To characterize the role of Rap1p in these processes in more detail, we studied the generation of telomeres in vivo from linear DNA substrates containing defined arrays of Rap1p binding sites. Consistent with previous work, our results indicate that synthetic Rap1p binding sites within the internal half of a telomeric array are recognized as an integral part of the telomere complex in an orientation-independent manner that is largely insensitive to the precise spacing between adjacent sites. By extending the lengths of these constructs, we found that several different Rap1p site arrays could never be found at the very distal end of a telomere, even when correctly oriented. Instead, these synthetic arrays were always followed by a short (≈100-bp) “cap” of genuine TG repeat sequence, indicating a remarkably strict sequence requirement for an end-specific function(s) of the telomere. Despite this fact, even misoriented Rap1p site arrays promote telomere formation when they are placed at the distal end of a telomere-healing substrate, provided that at least a single correctly oriented site is present within the array. Surprisingly, these heterogeneous arrays of Rap1p binding sites generate telomeres through a RAD52-dependent fusion resolution reaction that results in an inversion of the original array. Our results provide new insights into the nature of telomere end capping and reveal one way by which recombination can resolve a defect in this process.


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