CD69 is a TGF-β/1α,25-dihydroxyvitamin D3 target gene in monocytes

CD69 is a transmembrane lectin that can be expressed on most hematopoietic cells. In monocytes, it has been functionally linked to the 5-lipoxygenase pathway in which the leukotrienes, a class of highly potent inflammatory mediators, are produced. However, regarding CD69 gene expression and its regulatory mechanisms in monocytes, only scarce data are available. Here, we report that CD69 mRNA expression, analogous to that of 5-lipoxygenase, is induced by the physiologic stimuli transforming growth factor-β (TGF-β) and 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3) in monocytic cells. Comparison with T- and B-cell lines showed that the effect was specific for monocytes. CD69 expression levels were increased in a concentration-dependent manner, and kinetic analysis revealed a rapid onset of mRNA expression, indicating that CD69 is a primary TGF-β/1α,25(OH)2D3 target gene. PCR analysis of different regions of the CD69 mRNA revealed that de novo transcription was initiated and proximal and distal parts were induced concomitantly. In common with 5-lipoxygenase, no activation of 0.7 kb or ~2.3 kb promoter fragments by TGF-β and 1α,25(OH)2D3 could be observed in transient reporter assays for CD69. Analysis of mRNA stability using a transcription inhibitor and a 3′UTR reporter construct showed that TGF-β and 1α,25(OH)2D3 do not influence CD69 mRNA stability. Functional knockdown of Smad3 clearly demonstrated that upregulation of CD69 mRNA, in contrast to 5-LO, depends on Smad3. Comparative studies with different inhibitors for mitogen activated protein kinases (MAPKs) revealed that MAPK signalling is involved in CD69 gene regulation, whereas 5-lipoxygenase gene expression was only partly affected. Mechanistically, we found evidence that CD69 gene upregulation depends on TAK1-mediated p38 activation. In summary, our data indicate that CD69 gene expression, conforming with 5-lipoxygenase, is regulated monocyte-specifically by the physiologic stimuli TGF-β and 1α,25(OH)2D3 on mRNA level, although different mechanisms account for the upregulation of each gene

Dynamics of nuclear receptor target gene regulation

Ligand-regulated nuclear receptors, such as estrogen receptors, glucocorticoid receptor, vitamin D receptor, and peroxisome proliferator-activated receptors, belong to the most widely studied and best understood transcription factors. Therefore, the dynamic nature of transcriptional regulation was observed first with different members of the nuclear receptor superfamily, but is now also extended to other transcription factors, such as nuclear factor κB. Dynamic and in part cyclical processes were observed on the level of translocation into the nucleus, association with genomic binding sites, exchange of co-regulators and chromatin modifiers, occurrence of chromatin marks, and activities of RNA polymerase II resulting in mRNA synthesis. In this review, we summarize recent findings on the dynamic regulation of nuclear receptor target genes in the chromatin context

Nuclear receptor activation shapes spatial genome organization essential for gene expression control: lessons learned from the vitamin D receptor.

Spatial genome organization is tightly controlled by several regulatory mechanisms and is essential for gene expression control. Nuclear receptors are ligand-activated transcription factors that modulate physiological and pathophysiological processes and are primary pharmacological targets. DNA binding of the important loop-forming insulator protein CCCTC-binding factor (CTCF) was modulated by 1alpha,25-dihydroxyvitaminD3 (1,25(OH)2D3). We performed CTCF HiChIP assays to produce the first genome-wide dataset of CTCF long-range interactions in 1,25(OH)2D3-treated cells, and to determine whether dynamic changes of spatial chromatin interactions are essential for fine-tuning of nuclear receptor signaling. We detected changes in 3D chromatin organization upon vitaminD receptor (VDR) activation at 3.1% of all observed CTCF interactions. VDR binding was enriched at both differential loop anchors and within differential loops. Differential loops were observed in several putative functional roles including TAD border formation, promoter-enhancer looping, and establishment of VDR-responsive insulated neighborhoods. Vitamin D target genes were enriched in differential loops and at their anchors. Secondary vitamin D effects related to dynamic chromatin domain changes were linked to location of downstream transcription factors in differential loops. CRISPR interference and loop anchor deletion experiments confirmed the functional relevance of nuclear receptor ligand-induced adjustments of the chromatin 3D structure for gene expression regulation. © The Author(s) 2022. Published by Oxford University Press on behalf of Nucleic Acids Research

Gewaesserguetebericht 2000 - Sonderbericht 30 Jahre Biologische Gewaesserueberwachung in Nordrhein-Westfalen

In addition to research and monitoring work on the Land's flowing and stationary waters the employees of the Westphalian Water Management Administration have carried out myriad studies on a wide range of issues. Toxic freights; routine monitoring of wastewater dischargers using fish as bioindicators for testing clarified water for toxic effects; eutrophication of stationary waters and barrages; acidification of streams; development and possible uses of newly created lakes in the Rhine brown coal region; and concepts for the use and care of protected waters: all these were and still are issues that must be dealt with. Other fields of work include the further development of measuring methods for assessing toxic substances and the condition of waters. Last, not least biological and limnological studies form a basic component of rehabilitation planning and execution as well as of preventive water protection. New challenges will arise from the European Water Framework Directive with its ecosystemic approach. Some valuable scientific work has been carried out preparation of this in North-Rhine Westphalia.Neben Untersuchungs- und Ueberwachungsarbeiten ist an den fliessenden und stehenden Gewaessern des Landes fuer eine breite Palette unterschiedlicher Problemstellungen eine Fuelle von Arbeiten von den Mitarbeiterinnen und Mitarbeitern in der Wasserwirtschaftsverwaltung des Landes durchgefuehrt worden. Toxische Belastungen, routinemaessige Ueberwachung der Abwassereinleiter mit Fischen als Bioindikatoren zur Pruefung der Schadwirkungen gereinigten Abwassers, Eutrophierung stehender Gewaesser und Talsperren, Versauerung der Baeche, Entwicklung und Nutzungsmoeglichkeiten von neu entstandenen Seen im rheinischen Braunkohlerevier, Pflege- und Nutzungskonzepte fuer Naturschutzgewaesser waren und sind die Themen, denen nachgegangen werden muss. Die Weiterentwicklung der Messverfahren zur Beurteilung von toxischen Stoffen und fuer die Gewaesserbewertung sind weitere Arbeitsfelder. Nicht zuletzt sind biologisch-limnologische Untersuchungen ganz allgemeiner Bestandteil von Planungen und Massnahmen der Sanierung sowie des vorsorgenden Gewaesserschutzes. Neue Herausforderungen ergeben sich aus der Europaeischen Wasserrahmenrichtlinie mit ihrem oekosystemaren Ansatz. Hierzu sind in NRW bereits wertvolle naturwissenschaftliche Vorarbeiten geleistet worden.SIGLEAvailable from: http://www.lua.nrw.de/veroeffentlichungen/start / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman