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51.
Complementation study of peroxisome-deficient disorders by immunofluorescence staining and characterization of fused cells 总被引:5,自引:0,他引:5
Shigehiro Yajima Yasuyuki Suzuki Nobuyuki Shimozawa Seiji Yamaguchi Tadao Orii Yukio Fujiki Takashi Osumi Takashi Hashimoto Hugo W. Moser 《Human genetics》1992,88(5):491-499
Summary Genetic heterogeneity in peroxisome-deficient disorders, including Zellweger's cerebrohepatorenal syndrome, neonatal adrenoleukodystrophy and infantile Refsum disease, was investigated. Fibroblasts from 17 patients were fused using polyethylene glycol, cultivated on cover slips, and the formation of peroxisomes in the fused cells was visualized by immunofluorescence staining, using anti-human catalase IgG. Two distinct staining patterns were observed: (1) peroxisomes appeared in the majority of multinucleated cells, and (2) practically no peroxisomes were identified. Single step 12-(1-pyrene) dodecanoic acid/ultraviolet (P12/UV)-selection confirmed that the former groups were resistant to this selection, most of the surviving cells contained abundant peroxisomes, and the latter cells died. In the complementary matching, [1-14C]lignoceric acid oxidation and the biosynthesis of peroxisomal proteins were also normalized. Five complementation groups were identified. Group A: Zellweger syndrome and infantile Refsum disease; Groups B, C and D: Zellweger syndrome; Group E: Zellweger syndrome, neonatal adrenoleukodystrophy and infantile Refsum disease. We compared these groupings with those of Roscher and identified eight complementation groups. There was no obvious relation between complementation groups and clinical phenotypes. These results indicate that the transport, intracellular processing and function of peroxisomal proteins were normalized in the complementary matching and that at least eight different genes are involved in the formation of normal peroxisomes and in the transport of peroxisomal enzymes. 相似文献
52.
Ken-ichi Takita Akira Tanigami Takashi Tokino Carol Jones Yusuke Nakamura 《Genomics》1992,13(4):1296-1299
Fifty-four clones containing human inserts were selected from a cosmid library constructed from a somatic cell hybrid containing chromosome 11p15.3-p15.5 as its only human complement. In 32 of these clones, 63 polymorphic systems were identified with a panel of restriction enzymes: 57 conventional RFLP systems and 6 highly polymorphic VNTR systems. Although we examined the cosmid with only seven enzymes, 18 clones (including 6 VNTRs) were polymorphic with three or more enzymes. The results suggested that DNA sequences on the peritelomeric region of chromosome 11p tend to be highly variable. Because these markers are highly informative, they will be excellent resources for investigations of hereditary diseases and tumor suppressor genes in this region of chromosome 11. 相似文献
53.
Physical mapping of a 950-kb region surrounding a locus (D10S102) tightly linked to the MEN2A gene. 总被引:4,自引:0,他引:4
We have constructed a long-range contig of cosmid and YAC clones around D10S102, a locus that is tightly linked to the gene responsible for multiple endocrine neoplasia type 2A (MEN2A). With D10S102 as a starting point, a 360-kb cosmid contig was constructed by bidirectional genomic walking, and at least six fragments from these cosmids showed high sequence homology to other species. Five YAC clones were also isolated at the D10S102 locus, and they formed a contig covering 950 kb of genomic DNA. Furthermore, we obtained six RFLP systems from the contig, which will serve as new resources for fine-scale genetic linkage mapping of the MEN2A locus. 相似文献
54.
Kunio Nakagawa Norio Omori Kahoko Hashimoto Tetsuya Yamamoto Takashi Tsunoda Tadao Nose 《Biotherapy》1992,4(2):109-115
Thein vitro effect of a combined treatment with lymphokine activated killer (LAK) cell and radiation therapy on rat brain tumor was examined using51Cr release assay. The tumor cell-line used in this experiment was 9L rat brain tumor derived from a Fischer 344 rat. LAK cells were obtained by culturing rat lymphocytes with recombinant human interleukin 2 for at least 3 days. The cytotoxic activity of the LAK cells was examined by51Cr release assay. Irradiation was done by exposing the microtiter plate in which the15Cr labeled 9L cells and LAK cells were cultured to a137Cs gamma cell unit. Without irradiation, there was 18% cytotoxicity in the 1:100 tumor-to-LAK cell ratio specimen after 24 hrs cocultivation. However, if 5 Gy of irradiation was given, followed by 12 hrs incubation, the cytotoxicity was enhanced significantly at the same cell ratio (30%). This enhancement effect was the most prominent when the cell ratio was 1:100 and the irradiation dose was 5 Gy. To generate the enhancement effect, an incubation time of over 8 hrs both before and after irradiation was required. The supernatant of the LAK cells showed 19.8% and 11.4% cytotoxicity with and without irradiation, respectively. This result indicates the participation of a cytotoxic factor released from LAK cells.This work is supported in part by grant from Univeristy of Tsukuba Project Research. 相似文献
55.
An incomplete proviral genome of endogenous mammary tumour virus (MMTV) was found in DNA of several strains of mice. This MMTV-related sequence was assigned to the Y chromosome since it was clearly observed in male mice only. This MMTV provirus contained a sequence related to LTR (long terminal repeat), but not to gag-pol and env genes. NFS, NIH Swiss/S, STS/A, and DD/Tbr mice have this sequence but BALB/cHeA, SHN, SLN, C57BL/6NJcl, C3H/HeNJcl and CBA/JJcl mice are negative. In the strains containing this sequence, a DNA test for the sequence makes it possible to easily distinguish the DNAs of male or female mice. 相似文献
56.
Ayumi Ohsaki Yoshihisa Kasetani Yukihiro Asaka Kozo Shibata Takashi Tokoroyama Takashi Kubota 《Phytochemistry》1991,30(12):4075-4077
Three trans-clerodane diterpenoids, pilosanol A, B and C, the last compound being a glucoside, have been isolated from the roots of Portulaca pilosa. They show a marked contrast in skeletal type with the constituents of aerial part. Evolutionary changes in the biosynthetic abilities of Portulaca species is discussed. 相似文献
57.
Kazuhiro Yoshikawa Masao Seto Ryuzo Ueda Yuichi Obata Kunihiro Notake Takashi Yokochi Toshitada Takahashi 《Immunogenetics》1991,33(5-6):352-360
The CD7 molecule is a differentiation antigen found on the surface of T lymphocytes and also on a very minor fraction of acute nonlymphocytic leukemia (ANLL). To study the genomic structure of the CD7 gene, two clones (SY4 and SY22) were isolated by screening a genomic library with a CD7 cDNA probe. Restriction mapping of these two phage clones showed that both overlapped each other, covering a total length of 23 kilobases (kb). Transfection of mouse L cells demonstrated that SY22 contains the gene expressing the CD7 antigen reactive with monoclonal CD7 antibody (Tp40), while SY4 does not. Subcloning of a 10.5 kb fragment from a 14.4 kb insert of SY22 contained the structural gene for the CD7 antigen. Detailed restriction mapping and partial sequence analysis revealed the CD7 gene to consist of four exons. By RNase protection assay, multiple initiation sites — 122 base pairs (bp) to — 38 bp from ATG translation initiation site were demonstrated. The promoter region had high G+C content and contained two SP1 binding sites (CCGCCC) and an AP2 binding site (CCCCAGGC), but lacked CAAT and TATA motifs. 相似文献
58.
59.
60.
Takashi Saito Kensuke Futatsugi Daisuke Miki Hiroshi Suzuki Kiyoshi Yasukawa 《Biotechnology Techniques》1992,6(4):365-370
Summary Murine interleukin-6 (mIL-6) was expressed inEscherichia coli as human growth hormone (hGH) fusion protein. The products were cleaved by thrombin to liberate mIL-6. Monoclonal and polyclonal
antibodies specific to mIL-6 were prepared by immunizing rats with mIL-6 thus obtained. ELISA for the quantitation of mIL-6
was also established, which could detect mIL-6 in a quantity as low as 2 ng/ml. 相似文献