PU.1 is a myeloid- and lymphoid-specific transcription factor that belongs to the Ets family. Recently, we found that overproduction of PU.
View Article and Find Full Text PDFThe beta subunit of the high-affinity IgE receptor (FcepsilonRI) plays an important role in IgE-mediated allergic reactions as an amplifier for cell surface expression and signal transduction of FcepsilonRI. FcepsilonRIbeta is presumed to be one of the genes linked with atopic diseases. However, the validity of the associations previously found between single nucleotide polymorphisms (SNPs) in FcepsilonRIbeta and atopic diseases is questionable.
View Article and Find Full Text PDFBackground And Aim: Attachment of Helicobacter pylori to gastric epithelial cells leads to the production of chemokines, such as interleukin-8 (IL-8), which in turn activate and recruit neutrophils to the site of infection. Lafutidine [(+/-)-2-(furfurylsulfinyl)-N-(4-(4-(piperidinomethyl)-2-pyridyl)oxy-(Z)-2-butenyl)acetamide] is a new type of antiulcer drug that possesses an antisecretory action as well as gastroprotective activity, independent of its antisecretory action. In the present study, we examined the effects of lafutidine on H.
View Article and Find Full Text PDFHelicobacter pylori (H. pylori) infection of gastric epithelial cells has been shown to induce interleukin (IL)-8 production, but the signal transduction mechanism leading to IL-8 production has not been clearly defined. Here, we investigate the role of protein kinase C (PKC) in the mechanism of induction of IL-8 release by H.
View Article and Find Full Text PDFThe high affinity IgE receptor, FcepsilonRI, is a key regulatory molecule in the allergic reaction. By screening for cis-acting elements over the entire region of the human FcepsilonRI beta-chain gene, a sequence located in the fourth intron was revealed to serve as a repressor element. This element was recognized by a transcription factor, myeloid zinc finger protein 1 (MZF-1).
View Article and Find Full Text PDFWe found a novel polymorphism, -66T/C, in the promoter region of human FcepsilonRIalpha, the specific component of the high affinity receptor for IgE (FcepsilonRI), which is essential for the cell surface expression of FcepsilonRI and the binding of IgE Ab. When the effect of the single nucleotide replacement on the promoter function was analyzed, the transcription activity of the T allele promoter was found to be higher than that of the C allele promoter, and was markedly up-regulated by the overexpression of GATA-1 when compared with the C allele promoter. This is probably because the promoter with T at -66 has an additional GATA-1-binding motif in the region, which may assure higher affinity of the transcription factor to the promoter.
View Article and Find Full Text PDFThe beta chain, a component of the high-affinity receptor for IgE (FcepsilonRI), plays an important role in IgE-mediated allergic reaction. The beta chain accelerates the function of FcepsilonRI by amplification of its surface expression and of signal transduction in effector cells such as mast cells and basophils. Two regulatory regions, +60/+66 and +70/+76, for the human beta chain gene that are required for the cell-type-specific transcriptional activation were identified by transient reporter assay.
View Article and Find Full Text PDFThe alpha-chain of the high affinity receptor for IgE (Fc epsilon RI) is essential for cell surface expression of Fc epsilon RI and binding of the IgE Ab. The human alpha-chain gene possesses two promoters: the proximal promoter, which is highly conserved with that of rodent; and the distal promoter, the structure and role of which are largely unknown. Transcriptional regulation of the alpha-chain distal promoter was investigated in this study.
View Article and Find Full Text PDFThe FcR beta-chain, a subunit of two related multisubunit receptor complexes, the FcepsilonRI and FcgammaRIII, amplifies the mast cell response and is necessary for the cell surface expression of FcepsilonRI in mouse. The transient reporter assay indicated that -69/+4 region is required for cell type-specific transcriptional regulation of mouse beta-chain gene. EMSA using Abs against transcription factors or competitive oligonucleotides demonstrated that -58/-40 region (containing overlapping three GATA-1 sites, -53/-48, -46/-51, and -42/-47) and -31/-26 region (containing one GATA-1 site) are recognized by GATA-1.
View Article and Find Full Text PDFTranscriptional regulation of the gene-encoding human Fc epsilon RI alpha-chain was analyzed in detail. EMSA revealed that either YY1 or PU.1 bound to the region close to that recognized by Elf-1.
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