Publications by authors named "Hirayoshi K"

Control of interactions among proteins is critical in the treatment of diseases, but the specificity required is not easily incorporated into small molecules. Macromolecules could be more suitable as antagonists in this situation, and RNA aptamers have become particularly promising. Here we describe a novel selection procedure for RNA aptamers against a protein that constitutes a single structural domain, the Drosophila TATA-binding protein (TBP).

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The senescence-accelerated mouse is a model for senescence acceleration, a higher oxidative stress status, and age-associated disorders. We studied whether fibroblasts cultured from accelerated senescence-prone SAMP11 mice could be used as in vitro models for oxidative stress in senescence. Dichlorofluorescein and hydroethidine assays demonstrated that cells from SAMP11 mice produced more reactive oxygen species than did cells from accelerated senescence-resistant SAMR1 mice.

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A reduced adaptation to cold is a prominent feature in aged mammals, including humans. The accelerated senescence-prone strain of mice (SAMP) has been studied as an animal model for several age-associated disorders and in the acceleration of senescence. Recent studies revealed that SAMP strains have dysfunctional hyperactive mitochondria and are under a higher oxidative stress status from a young age.

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A shift from 28 to 37 degrees C in the incubation temperature of a culture of the platyfish fibroblast cell line, EHS cells (platyfish fibroblast cell line), induced a set of stress proteins. A two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) analysis showed that the cells expressed three genetically distinct forms of heat-shock protein 70 (HSP70) family proteins: heat-inducible forms of HSP70, the constitutively expressed heat-shock cognate protein 70 (HSC70) and its phosphorylated isoform, and the glucose-regulated protein 78 (GRP78). Three different clones encoding two major isoforms of heat-inducible HSP70, platyfish HSP70-1 and HSP70-2, and of the HSC70 were isolated from a platyfish cDNA library.

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In several cells and tissues the synthesis of HSP47, a collagen-specific molecular chaperone in the endoplasmic reticulum, is closely correlated with the synthesis of collagen. We previously reported that the Sp1 binding site at -210 bp in the promoter region and the first and second introns are required for the tissue-specific expression of HSP47 in transgenic mice (Hirata, H., Yamamura, I.

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Basal laminae beneath alveolar type I cells are suggested to contain highly sulfated heparan sulfate-containing proteoglycans (PGs), and cultured type II cells accumulate highly sulfated matrices. To characterize the regulation of PG synthesis during the transition from type II cells to type I cells, we examined mRNA expression of N-deacetylase/sulfotransferase (NST) and 3-O-sulfotransferase (3-OST), two enzymes specific for heparan sulfate synthesis. We found that both freshly isolated and cultured type II cells expressed NST and 3-OST as shown by in situ hybridization.

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HSP47 is a collagen-binding heat shock protein and is assumed to act as a molecular chaperone in the biosynthesis and secretion of procollagen. As the synthesis of HSP47 is closely correlated with that of collagen in various cell lines and tissues, we performed a promoter/reporter assay using HSP47-producing and nonproducing cells. 280 base pairs (bp(s)) of upstream promoter were shown to be necessary for the basal expression but not to be enough for the cell type-specific expression.

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A new method is described for cloning DNA sequences occupied by a specific protein on chromatin in vivo . The approach uses UV cross-linking to couple proteins covalently to DNA and the resulting complexes are then purified under stringent conditions. Particular adducts are immunoprocipitated with antibody to the protein of interest.

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Heat shock protein 47 (HSP47), a collagen-specific stress protein, has been postulated to be a collagen-specific molecular chaperone localized in the ER. We previously demonstrated that HSP47 transiently associated with newly synthesized procollagen in the ER (Nakai, A., M.

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To investigate the regulatory mechanisms controlling expression of the vimentin-encoding gene (Vim) during mouse myeloid leukemia M1 cell differentiation, mouse Vim was cloned and the transcriptional activity of its 5' promoter region was analysed by chloramphenicol acetyltransferase (CAT) assay. Analyses of various deletion mutants revealed that a 188-bp fragment of the proximal Vim promoter (pVim) was sufficient for effective transcription in M1 cells. This 188-bp sequence is highly conserved between mouse, hamster and human.

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Chromatin structure can modulate gene expression by limiting transcription factor access to gene promoters. We examined sequence elements of the Drosophila hsp70 promoter for their ability to facilitate the binding of the transcription factor, heat shock factor (HSF), to chromatin. We assayed HSF binding to various transgenic heat shock promoters in situ by measuring amounts of fluorescence at transgenic loci of polytene chromosomes that were stained with an HSF antibody.

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A 47-kDa heat shock protein (HSP47) is a collagen-binding stress protein which is localized in the endoplasmic reticulum (ER) of collagen-secreting cells. Recent studies have shown that HSP47 transiently binds to newly synthesized procollagens and that conformationally abnormal procollagen is also bound by HSP47 for a much longer time in the ER (Nakai, A., Satoh, M.

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HSP47 is a collagen-binding stress protein and is assumed to act as a collagen-specific molecular chaperone during the biosynthesis and secretion of procollagen in the living cell. The synthesis of HSP47 has been reported to correlate with that of collagen in several cell lines. We examined the expression of HSP47 mRNA during the progression of carbon tetrachloride (CCl4)-induced liver fibrosis in rats.

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The heat shock proteins (hsp) are regarded as being immunogenic to the animal hosts. Although certain hsp are suggested to be expressed on the cell surface, further evidence for the cell surface expression of these proteins has been required. In this article we report the development of a MAb NT22.

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We investigated the distribution of heat shock protein 47 (hsp47) in cultured chicken embryonic chondrocytes and epiphyseal chondrocytes of tibial bones from 1-day-old to 6-week-old chickens. Northern blot and immunoblot analyses revealed that hsp47 exists in epiphyseal cartilage and cultured chondrocytes. Confocal laser immunofluorescence microscopy showed that hsp47 was localized mainly in the many granular structures found in the cytoplasm that contain Type II collagen.

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pSE48 was one of six clones selected by differential colony hybridization as a cDNA coding for mRNA expressed in parietal endoderm-like F9 cells and not in primitive endoderm-like F9 cells. It was sequenced and identified as a segment of mouse osteonectin (SPARC) cDNA. We found osteonectin to be heat-inducible in some cells.

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We examined the effect of ATP on the terminal differentiation of mouse myelomonocytic leukemic M1 cells to macrophages. Although ATP alone did not induce M1 cell differentiation, addition of ATP with the differentiation inducer, interleukin 6 (IL-6), enhanced the induction of differentiation by IL-6 about two-fold. Comparison among several adenine nucleotides revealed that the order of effectiveness on differentiation enhancement was ATP > ADP > AMP > or = adenosine.

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The mouse HSP47 gene consists of six exons separated by five introns. Three HSP47 cDNAs differing only in their 5' noncoding regions have been reported. One of these alternatively spliced mRNAs was detected only after heat shock, which caused an alternative 5' splice donor site selection.

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HSP47, a 47-kDa heat-shock protein (HSP), is a member of a group of HSPs with the unique characteristics of collagen binding as well as transformation sensitivity. The protein belongs to the serpin (serine protease inhibitor) superfamily as determined from its amino acid sequence homology. We have isolated and characterized the mouse HSP47 including about 1 kb of the 5'-flanking region.

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The phosphorylation of glucose-regulated protein, GRP78, is thought to be involved in the regulation of the binding function of GRP78 to immunoglobulin heavy chains. The phosphorylation of GRP78 proceeded faster in transformed cells than in normal cells, whereas the levels of GRP78 synthesis and accumulation were similar in both cells. Treatment of the cells with tunicamycin caused a rapid decrease in GRP78 phosphorylation within 2 to 4 h in both cell types prior to GRP78 induction.

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We examined the effect of leukemia inhibitory factor (LIF) on the expression of interleukin 6 receptors (IL-6R) on mouse myelomonocytic leukemic M1 cells. Binding studies using 125I-labeled human and murine IL-6 revealed that LIF caused a decrease in IL-6 binding to M1 cells. The decrease became evident within 1 h, and the maximum decrease was observed at 3-6 h.

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Here, we describe the effects of quercetin on the induction of thermotolerance as examined by colony forming assay in a cell line derived from human colon carcinoma (COLO320 DM). Cells became resistant to heat treatment at 45 degrees C when they were preheated at 42 degrees C for 1.5 h or at 45 degrees C for 10 min.

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Transcriptional activation of human heat shock protein (HSP) genes by heat shock or other stresses is regulated by the activation of a heat shock factor (HSF). Activated HSF posttranslationally acquires DNA-binding ability. We previously reported that quercetin and some other flavonoids inhibited the induction of HSPs in HeLa and COLO 320DM cells, derived from a human colon cancer, at the level of mRNA accumulation.

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A 47-kDa heat-shock protein (HSP47) is a major collagen-binding stress protein residing in the endoplasmic reticulum, and is assumed to be a molecular chaperone specific to collagen. Two-dimensional gel electrophoresis and immunoprecipitation studies showed that the expression of HSP47 was significantly induced during the differentiation of mouse teratocarcinoma F9 cells by treatment with retinoic acid alone or with retinoic acid and dibutyryladenosine 3',5'-phosphate. The induction of type-IV collagen was also observed during F9-cell differentiation.

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