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21.
Park Keun-Hyung; Fujisawa Sachiko; Sakurai Akira; Yamaguchi Isomaro; Takahashi Nobutaka 《Plant & cell physiology》1983,24(7):1241-1249
Endogenous gibberellins (GAs) in several kinds of crown gallcells and cultured cells derived from normal tissue of Nicotianatabacum were systematically analyzed by gas chromatography-selectedion current monitoring (GC-SICM) after chromatographic purifications,and GA1, GA9, GA19 and GA20 were identified. Agrobacterium tumefaciens,a pathogen of crown gall, was confirmed not to produce GAs inits culture. We also investigated endogenous GAs of mother plant,tobacco, and found the same kinds of GAs as in cultured cells.
3 Present address: College of Agriculture, Chonnam NationalUniversity, Kwangju 500, Korea. (Received May 19, 1982; Accepted July 22, 1983) 相似文献
22.
Efficient expression of genetically engineered hepatitis B virus surface antigen P31 proteins in yeast 总被引:3,自引:0,他引:3
We have constructed plasmids that express modified hepatitis B virus surface antigen (HBsAg) P31-coding genes (M-P31c, d, e, f, and i) having various genetically engineered pre-S2 regions. The plasmids contain the GAPDH (gene coding for glyceraldehyde-3-phosphate dehydrogenase) promoter and the PGK (gene coding for 3-phosphoglycerate kinase) terminator, both isolated from sake brewing yeast, Saccharomyces cerevisiae Kyokai III. Expression levels of the modified HBsAg P31 proteins in yeast are greatly increased from 0.4% to 11.7% of total cell protein. However, the specific mRNAs are expressed at equal levels and the degradation rates of the modified P31 proteins do not vary significantly. Therefore, we considered that different expression levels of the modified P31 proteins are attributed to the changes of the post-translational efficiency. And it was suggested that the conformational stability of the N-terminal peptide (Met-1-Phe-46) in the endoplasmic reticulum membrane determines the expression level of modified P31 proteins. 相似文献
23.
Kenichi Ogasawara Makoto Bannai Naruya Saitou Ryuichi Yabe Kenichi Nakata Michiko Takenaka Kiyoshi Fujisawa Makoto Uchikawa Yoshihide Ishikawa Takeo Juji Katsushi Tokunaga 《Human genetics》1996,97(6):777-783
Polymorphism of the ABO blood group gene was investigated in 262 healthy Japanese donors by a polymerase chain reactions-single-strand conformation polymorphism (PCR-SSCP) method, and 13 different alleles were identified. The number of alleles identified in each group was 4 for A1 (provisionally called ABO*A101, *A102, *A103 and *A104 according to the guidelines for human gene nomenclature), 3 for B (ABO*B101, *B102 and *B103), and 6 for O (ABO*O101, *O102, *O103, *O201, *O202 and *O203). Nucleotide sequences of the amplified fragments with different SSCP patterns were determined by direct sequencing. Phylogenetic network analysis revealed that these alleles could be classified into three major lineages, *A/*O1, *B and *O2. In Japanese, *A102 and *13101 were the predominant alleles with frequencies of 83% and 97% in each group, respectively, whereas in group O, two common alleles, *O101 (43%) and *O201 (53%), were observed. These results may be useful for the establishment of ABO genotyping, and these newly described ABO alleles would be advantageous indicators for population studies. 相似文献
24.
Souhei Sugita Misako Namima Toshitaka Nabeshima Koichi Okamoto Hiroshi Furukawa Yasuhiro Watanabe 《Neurochemistry international》1996,28(5-6):545-550
For the purpose of studying a role of immediate early genes in psychotomimetic-induced behavioral excitation, we experimentally enhanced the locomotor activity of mice by acute administration of phencyclidine and examined the expression and localization of the c-Fos-like and c-Jun-like immunoreactivities in brain regions. A single injection of phencyclidine (5.0 mg/kg, i.p.) significantly increased not only the locomotor activity but also the expression of c-Fos-like immunoreactivity in several brain regions, particularly in the parietal cortex, hippocampal dentate gyrus, piriform cortex and hypothalamus. Interestingly, the c-Fos-like immunoreactivity in the parietal cortex continued to increase for 1 week after the phencyclidine injection. These results indicate that phencyclidine, even injected only once, can induce the persistent expression of c-Fos or c-Fos-related protein(s) in the mouse brain, and also suggest the possibility that such a c-Fos expression may underlie the behavioral and/or psychotomimetic effects of phencyclidine. 相似文献
25.
T. FUJISAWA AND M. MORI. 1996. The β-glucuronidase activity of intact cells of Escherichia coli and Clostridium perfringens was increased in the presence of bile salts. In contrast, bile salts had inhibitory effects on the activity of β-glucuronidase extracted from the lysed cells. These results suggest that the permeability of the bacterial cells is increased by the presence of bile salts, and that bile salts may significantly enhance bacterial β-glucuronidase activity in the intestinal tract. 相似文献
26.
27.
Kawarabayasi Yutaka; Tanaka Ayako; Ohara Osamu; Arakawa Taku; Oka Masanori; Kato Hisako; Morita Miyo; Fujisawa Hisao 《DNA research》1994,1(6):289-296
To sequence a DNA segment inserted into a cosmid vector underthe directed sequencing strategy, we established a simple andrapid method for generating nested deletions which uses thein vitro packaging system of bacteriophage T3 DNA. The principleis based on the previous finding that this system can translocateany linear double-stranded DNA up to 40 kb into the phage capsidin a time-dependent manner and the encapsulated DNA becomesDNase-resistant. For this purpose, we constructed a cosmid vectorthat carries two different antibiotic selection markers at bothsides of the multiple cloning site, and after insertion of aDNA segment, the clone was linearized by -terminase at the cossite. After the packaging reaction in vitro followed by DNasetreatment, the encapsulated DNA was introduced into Escherichiacoli cells to give clones with unidirectional deletions by differentialantibiotic selection. Restriction and sequence analyses of deletionclones demonstrated that an ordered set of clones with nesteddeletions, ranging from less than 1 kb to 25 kb, was createdfrom either the end of the DNA segment. Thus, nested deletionclones that cover the entire region of a 40-kb cosmid insertcan be obtained by a single packaging reaction, and its restrictionmap can be simultaneously obtained. 相似文献
28.
A new regulatory element that augments the Tax-dependent enhancer of human T-cell leukemia virus type 1 and cloning of cDNAs encoding its binding proteins. 总被引:5,自引:3,他引:2
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The Tax protein of human T-cell leukemia virus type 1 (HTLV-1) trans activates the 21-bp enhancer of HTLV-1. A sequence of more than two copies of the 21-bp enhancer is efficiently activated by Tax, but one copy is not activated extensively. Another sequence (TRE-2, positions -163 to -117) adjacent to the 21-bp enhancer in the long terminal repeat of HTLV-1 can enhance a single copy of the 21-bp enhancer activity in trans activation by Tax. This sequence contains motifs related to the Ets- and NF-kappa B-binding sequences, but mutations at these sites indicated that neither is responsive to cooperation with the 21-bp enhancer. A deletion mutation of TRE-2 identified 25 bases at positions -158 to -134 (TRE-2S) as an essential sequence, and TRE-2S was sufficient to give maximum cooperation with one copy of the 21-bp enhancer in trans activation by Tax protein. Using TRE-2S as a probe, we screened a cDNA library of HUT102 cells by the Southwestern (DNA-protein) procedure and isolated two cDNA clones, THP-1 and -2. These two clones encode TRE-2S-binding proteins, and they differ by only an extra 17 amino acids in THP-2. Both THP proteins contain five zinc finger motifs which are strikingly similar to those of the GLI family, an amplified gene product in glyoma cells. The binding site of THP-1 and -2 was GAACCACCCA in TRE-2S, which is highly homologous to the GLI-binding site. These results suggest that binding of THP to TRE-2S may be involved in cooperation with one copy of the 21-bp enhancer in responding to Tax trans activation. 相似文献
29.
Hisao Yamaguchi Keiko Hosokawa Zheng-Lin Jiang Akira Takahashi Toshitaka Ikehara Hiroshi Miyamoto 《Journal of cellular biochemistry》1993,53(1):13-20
Cell cycle progression of synchronized HeLa cells was studied by measuring labeling of the nuclei with [3H]thymidine. The progression was arrested in a chemically defined medium in which K+ was replaced by Rb+ (Rb-CDM) but was restored upon addition of insulin and/or low density lipoprotein (LDL). Cells started DNA synthesis 12 hr after addition of insulin and/or LDL, regardless of the time of arrest, suggesting their arrest early in the G1 phase. After incubation of cells in Rb-CDM containing insulin or LDL singly for 3, 6, or 9 hr, replacement of the medium by that without an addition resulted in marked delay in entry of cells into the S phase, but in its replacement by medium containing both agents, the delay was insignificant. Synthesis of bulk protein, estimated as increase in the cell volume, was not strongly inhibited. From these results we conclude that cell cycle progression of HeLa cells in K?-depleted CDM is arrested early in the G1 phase and that the arrest is due to lack of some protein(s) required for entry into the S phase that is synthesized in the early G1 phase. 相似文献
30.
An Improved Enrichment Broth for Isolation of Escherichia coli O157, with Specific Reference to Starved Cells, from Radish Sprouts
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Shin Sata Tomohiko Fujisawa Ro Osawa Atsushi Iguchi Shiro Yamai Toshio Shimada 《Applied microbiology》2003,69(3):1858-1860
An enrichment broth was developed for the efficient isolation of Escherichia coli O157 from radish sprouts. The broth was buffered peptone water containing 0.5% sodium thioglycolate (STG-BPW), which was designed to allow growth of E. coli O157 in starved and unstarved states. However, this medium suppressed the growth of non-carbohydrate-fermenting obligate aerobes whose colonial appearance on sorbitol MacConkey agar containing cefixime and tellurite (CT-SMAC) resembled that of E. coli O157. Both starved and unstarved cells of E. coli O157 experimentally inoculated into radish sprouts were successfully recovered with STG-BPW enrichment in all cases, most of which showed marked disappearance of E. coli O157-like colonies on CT-SMAC. 相似文献