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21.
Yoichi Honda Toshikazu Irie Mina Atsuji Takashi Watanabe Masaaki Kuwahara 《Mycoscience》1996,37(4):459-461
To develop a dominant genetic marker inPleurotus ostreatus, mutant strains resistant to a carboxin-derived fungicide, flutolanil, were isolated. These mutants included strains which
showed resistance to 50-fold higher concentration of fluotolanil than the wild-type strain, even after successive cultivations
in the absence of the drug. Dominance of the phenotype was confirmed by back-crossing between the resistant and wild-type
monokaryons. The flutolanilresistance was also shown to be stably inherited by the basidiospore-derived progenies of the mutant
strains. 相似文献
22.
Wataru Shibata Hiroharu Banno Yukihiro Ito Keiko Hirano Kenji Irie Shoji Usami Chiyoko Machida Yasunori Machida 《Molecular & general genetics : MGG》1995,246(4):401-410
A cDNA (cNPK2) that encodes a protein of 518 amino acids was isolated from a library prepared from poly(A)+ RNAs of tobacco cells in suspension culture. The N-terminal half of the predicted NPK2 protein is similar in amino acid sequence to the catalytic domains of kinases that activate mitogen-activated protein kinases (designated here MAPKKs) from various animals and to those of yeast homologs of MAPKKs. The N-terminal domain of NPK2 was produced as a fusion protein in Escherichia coli, and the purified fusion protein was found to be capable of autophosphorylation of threonine and serine residues. These results indicate that the N-terminal domain of NPK2 has activity of a serine/threonine protein kinase. Southern blot analysis showed that genomic DNAs from various plant species, including Arabidopsis thaliana and sweet potato, hybridized strongly with cNPK2, indicating that these plants also have genes that are closely related to the gene for NPK2. The structural similarity between the catalytic domain of NPK2 and those of MAPKKs and their homologs suggests that tobacco NPK2 corresponds to MAPKKs of other organisms. Given the existence of plant homologs of an MAP kinase and tobacco NPK1, which is structurally and functionally homologous to one of the activator kinases of yeast homologs of MAPKK (MAPKKKs), it seems likely that a signal transduction pathway mediated by a protein kinase cascade that is analogous to the MAP kinase cascades proposed in yeasts and animals, is also conserved in plants. 相似文献
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25.
Giuliano Armando E. Irie Reiko F. Morton Donald L. 《Cancer immunology, immunotherapy : CII》1981,10(4):243-249
Summary The oncofetal antigen-I (OFA-I) has been defined as an immunogenic antigen that is expressed on human cancer cells and is cross reactive with fetal brain tissue. Quantitative variations in the expression of OFA-I among different cultured melanoma cell lines were determined by absorption techniques based on functionally monospecific anti-OFA-I serum. Allo-antibodies were removed by absorption with lymphoblasts autologous to an OFA-I-positive target cell. Functional monospecificity toward OFA-I was confirmed by complete absorption with a specimen of fetal brain but not by liver from the same fetus.Of 14 melanoma cell lines tested, two did not express OFA-I, whereas 12 expressed the antigen to varying degrees. Five of the cell lines were highly antigenic, and serum absorbed with 5×105 of any of these cell lines could reduce the anti-OFA-I titer (1 : 96) at least four-fold. OFA-I was detected on biopsied melanomas autologous to the antigenic cultured cells. The ability to select highly antigenic cell lines could be useful in further attempts to characterize OFA-I and to monitor tumor immunity in vitro. Antigenic cell lines may improve the response of patients treated in trials of immunotherapy. 相似文献
26.
In addition to its many functions in biosynthesis, growth, coagulation and rheology, vascular endothelium is anatomically interposed between the vascular space and the tissue fluid. Recent evidence indicates that it mediates cellular and molecular exchange between these compartments. The exchange can occur through differentiated microdomains of endothelium such as fenestrae. These areas are differentiated with regard to surface charge, protein distribution within the lipid bilayer, membrane fluidity and other features. The exchange is also affected by certain characteristics of the molecule to be transported: molecular size, charge, shape and its carbohydrate content. Proportionately, the largest volume of exchange occurs across the endothelial cytoplasm by vesicular transport systems. Two systems are particularly in evidence; (a) receptor-mediated transcytosis which is specific, and (b) fluid-phase endocytosis. The molecule may become modified in transit and the modification may be of essence in determining its target point and its subsequent metabolism. While most of these modifications involve the carbohydrate moiety of the glycoproteins, glycosylation of non-glycoproteins such as albumin, may also be of physiological significance in transendothelial transport. By virtue of its transport potential, albumin can thus affect the transport of other substances. Recent advances in the molecular transport function of endothelium have been reviewed in the context of its physiological and clinical significance. The basis for the concept of a generalized tissue-blood barrier has been offered. 相似文献
27.
A novel fucose-containing neutral glycosphingolipid (GL-5) was purified from the eggs of the sea urchin, Hemicentrotus pulcherrimus. The chemical structure was determined to be Fuc alpha 1-3GalNAc beta 1-4(Fuc alpha 1-3)GlcNAc beta 1-4Glc beta 1-1Cer by methylation analysis, partial acid hydrolysis, fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectroscopy. The unique characteristics of GL-5 are that: the reducing terminal disaccharide portion is not Gal beta 1-4Glc but GlcNAc beta 1-4Glc; it includes a GalNAc beta 1-4GlcNAc sequence and a Fuc-GalNAc linkage; the defucosylated core is a novel trisaccharide chain; and the sugar structure is one of the smallest ever characterized for a difucosylated glycolipid. The major fatty acids were 22:1 and 22h:1, and about 30% of the total acids was 2-hydroxylated. All the long-chain bases were phytosphingosines, of which about 90% was n-t18:0. The similarity of the ceramide moiety to that of glucosylceramide from the same eggs [Kubo, H. et al. (1992) J. Biochem. 111, 726-731] suggests a close biosynthetic relationship between GL-5 and the glucosylceramide. 相似文献
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29.
Adipocytes from adrenalectomized rats nearly lost their lipolytic response to glucagon concomitant with a 90% decrease in the number of glucagon receptors per cell. Quantitative analysis of the relation between amount of cell-bound glucagon and hormone-stimulated lipolysis revealed that the ability of the remaining 10% of glucagon receptors to induce lipolysis was not impaired. Binding of the beta-adrenergic antagonist [3H]dihydroalprenolol and maximal lipolysis induced by (-)-isoproterenol, (Bu)2cAMP, 3-isobutyl-1-methylxanthine, and adenosine deaminase were reduced only 10 to 20% after adrenalectomy. Furthermore, glucagon-stimulated cAMP production was greatly decreased in adrenalectomized animals, but isoproterenol-stimulated cAMP production was not. Hydrocortisone replacement in adrenalectomized rats only partially prevented the loss of glucagon receptors and glucagon effects on both cAMP production and lipolysis. These findings suggest that lipolytic cascade distal to hormone receptors was not greatly impaired in adipocytes after adrenalectomy and that the unresponsiveness of these cells to glucagon was mostly due to a marked reduction in the number of glucagon receptors. 相似文献
30.
Neil Sidell Reiko F. Irie S. David Nathanson Donald L. Morton 《Cancer immunology, immunotherapy : CII》1980,9(1-2):49-54
Summary IgG anti-OFA-I found in melanoma patients was tested for its ability to lyse human tumor cells in antibody-dependent cell-mediated cytotoxicity (ADCC). Sera from 89 stage II melanoma patients which contained non-HLA-related IgG antibody to an OFA-I-positive melanoma cell line (M14) as tested by indirect membrane immunofluorescence (IMI) were originally chosen as possible sources of IgG anti-OFA-I. Of those tested for specific IgG activity to OFA-I by IMI, anti-OFA-I was found only in those patients immunized with OFA-I-positive tumor cells. When the same sera were tested in ADCC, no non-HLA-related activity could be demonstrated. This result was confirmed with purified IgG fractions that could, nevertheless, show anti-OFA-I reactivity in a complement-dependent cytotoxicity assay. The fact that naturally occurring IgG anti-OFA-I antibody was not readily detectable in patients' sera and that induced IgG anti-OFA-I did not participate in ADCC indicates that OFA-I-related tumor cell lysis via ADCC is an unlikely phenomenon in cancer patients. 相似文献