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11.
Identification of a single nucleotide change in a mutant gene for hypoxanthine-guanine phosphoribosyltransferase (HPRTAnn Arbor) 总被引:1,自引:1,他引:0
Shin Fujimori Yuji Hidaka Beverly L. Davidson Thomas D. Palella William N. Kelley 《Human genetics》1988,79(1):39-43
Summary HPRTAnn Arbor is a variant of hypoxanthine (guanine) phosphoribosyl-transferase (HPRT: EC 2.4.2.8), which was identified in two brothers with hyperuricemia and nephrolithiasis. In previous studies, this mutant enzyme was characterized by an increased Km for both substrates, a normal Vmax, a decreased intracellular concentration of enzyme protein, a normal subunit molecular weight and an acidic isoelectric point under native isoelectric focusing conditions. We have cloned a full-length cDNA for HPRTAnn Arbor and determined its complete nucleotide sequence. A single nucleotide change (TG) at nucleotide position 396 has been identified. This transversion predicts an amino acid substitution from isoleucine (ATT) to methionine (ATG) in codon 132, which is located within the putative 5-phosphoribosyl-1-pyrophosphate (PRPP)-binding site of HPRT. 相似文献
12.
Yoshiaki Fukuda Kohzoh Imai Kenju Miura Masashi Matsui Toshihiro Nakanishi Hiroshi Nakazato Johji Masukawa Toshiyuki Higashide Yuji Hinoda Teruhisa Noguchi Akira Yachi 《Cancer immunology, immunotherapy : CII》1988,27(1):26-32
Summary There have been few reports stating that monoclonal antibody alone inhibits human solid tumor growth in vivo. The present study demonstrated that monoclonal antibody S1 (IgG2a), which recognized the antigenic determinant of the carbohydrate moiety, showed antibody-dependent cell (or macrophage)-mediated cytotoxicity (ADCC or ADMC) in conjunction with murine splenocytes of both BALB/c and athymic mice. In vivo experiments demonstrated that the antibody S1 clearly prolonged the survival of athymic mice which had been inoculated with a human liver carcinoma cell line. In addition, the antibody S1 significantly suppressed the human hepatoma line transplanted s.c. into nude mice. 125I-Labeled monoclonal antibody S1 revealed that the antibody accumulated significantly in the tumor mass. Many mononuclear cells were observed surrounding tumor cells when the antibody was given. This model system might be useful for analyzing the ADCC (or ADMC) mechanism in vivo. 相似文献
13.
Yuji Okawara David Ko Steven D. Morley Dietmar Richter Karl P. Lederis 《Cell and tissue research》1992,267(3):545-549
Summary In situ hybridization procedure with a 32P-labelled synthetic oligonucleotide probe was used to detect corticotropin-releasing factor-encoding messenger RNA (CRF mRNA) in the hypothalamus of the white sucker, Catostomus commersoni. Adjacent sections were immunostained by a sucker CRF-specific antiserum. CRF mRNA-containing neurons were identified by autoradiography in the magnocellular and parvocellular subdivisions of the preoptic nucleus (PON). Many of these neurons were also immunostained by sucker antiserum, showing the same distribution patterns. These results confirm the presence of CRF mRNA and CRF peptide in the white sucker hypothalamus and support the view that the magnocellular and parvocellular neurons of the PON may be involved in the control of adrenocorticotropic hormone secretion from the pituitary in the white sucker. 相似文献
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16.
Hidenori Shinkawa Masanori Sugiyama Yuji Hatada Takeshi Ohuchi Masao Udagawa Osamu Nimi 《Biotechnology letters》1991,13(8):537-542
Summary The bald mutants from streptomycin (SM)-producingStreptomyces griseus 2247 obtained by incubation at high temperature (36° C), designated as HT strains, lost resistance to their own antibiotic and scarcely produced the antibiotic. Although SM susceptibility in the mutant was due to loss of SM 6-phosphotransferase activity produced in the cell, the gene coding for the enzyme cloned from an HT strain was surely expressed inS. lividans 1326 as a host. Northern blot analysis showed that the corresponding RNA is not detected in the mutant, indicating that though the gene encoding SM 6-phosphotransferase, at least, the structural gene is not deleted in the cell, the expression is silent. 相似文献
17.
Gene structure and expression of a tobacco endochitinase gene in suspension-cultured tobacco cells 总被引:8,自引:0,他引:8
We have isolated and characterized the genomic clone CHN50 corresponding to tobacco basic endochitinase (E.C.3.2.1.14). DNA sequence and blotting analysis reveal that the coding sequence of the gene present on CHN50 is identical to that of the cDNA clone pCHN50 and, moreover, the CHN50 gene has its origin in the progenitor of tobacco, Nicotiana sylvestris. Tobacco basic chitinases are encoded by a small gene family that consists of at least two members, the CHN50 gene and a closely related CHN17 gene which was characterized previously. By northern blot analysis, it is shown that the CHN50 gene is highly expressed in suspension-cultured tobacco cells and the mRNA accumulates at late logarithmic growth phase. To identify cis-DNA elements involved in the expression of the CHN50 gene in suspensioncultured cells, the chimeric gene consisting of 1.1 kb CHN50 5 upstream region fused to the coding sequence of -glucuronidase (GUS) was introduced by electroporation into protoplasts isolated from suspension-cultured tobacco cells. Transient GUS activity was found to be dependent on the growth phase of the cultured cells, from which protoplasts had been prepared. Functional analysis of 5 deletions suggests that the distal region between -788 and -345 contains sequences that potentiate the high-level expression in tobacco protoplasts and the region (-68 to -47) proximal to the TATA box functions as a putative silencer. 相似文献
18.
Endo S Inada K Inoue Y Otsu T Kasai T Kuwata Y Hoshi S Yoshida M 《Mediators of inflammation》1992,1(1):45-48
Plasma levels of endotoxin and various cytokines were assessed in 70 patients with gastrointestinal tract perforation. Sepsis developed in 29 of them, and eight of these (27.6%) had on admission endotoxin levels higher than 9.8 pg ml(-1). The clinical outcome correlated with the level of tumour necrosis factor alpha (TNFalpha), rather than with the endotoxin level. The high interleukin 6 (IL-6) level was shown in septic patients and no correlation was observed between the IL-6 level and the clinical outcome. Plasma TNFalpha levels tended to change independently from endotoxin levels, suggesting that TNFalpha may have been locally produced in inflammatory lesions. 相似文献
19.
R Y Osamura Y Suemizu S Yoshimura S Hori K Inada K Watanabe Y Nakai H Imura 《Peptides》1991,12(3):503-507
In order to elucidate the relationship between secretory pathway and processing for precursor molecule of peptide hormones, we performed immunoelectron microscopic studies to localize POMC-derived peptides in mouse cultured L cells (fibroblasts without secretory granules) and in mouse AtT20 cells (ACTH secreting pituitary tumor cells with secretory granules) which had been transformed with human POMC gene. From the electron microscopic localization patterns, L42 cells were considered to serve as a model of constitutive pathway without processing of POMC, and A53 cells were considered to serve as a model of transgranular (regulated) pathway with processing of POMC. Immunoblotting supported these interpretations. 相似文献
20.
K Inada S Endo K Takahashi M Suzuki T Narita T Yoshida H Suda T Komuro M Yoshida 《Microbiology and immunology》1991,35(4):303-314
We established a new method of plasma treatment for the removal of interfering factors in the plasma to allow detection of endotoxin by limulus test. The limulus test used was an endotoxin-specific chromogenic test, the Endospecy test. Perchloric acid (PCA) treatment and centrifugation (PCA method) is usually used to remove interfering factors from plasma, with the precipitate being discarded and the supernatant used to detect endotoxin. As the solubilized precipitates of endotoxin-spiked plasma and some patient plasma were found to contain the Endospecy activity, we have devised a new method assaying endotoxin in both the supernatant and precipitate. This study confirmed that the solubilized precipitate of endotoxin-spiked plasma had Endospecy activity and found that the precipitate had other endotoxin activities, such as lethality in galactosamine-sensitized mice and pyrogenicity in rabbits. We also confirmed that interfering factors were completely removed from plasma samples by this new method. The endotoxin level after the new PCA method was found to be about 8 times higher than that determined after PCA treatment and the new PCA method surpasses the conventional PCA method with regard to the positive rate of endotoxin contents in clinical samples. These results indicate that the new PCA method is superior to the PCA method as a plasma pretreatment method for limulus test. 相似文献