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1.
Junzou Hiratsuka Hiroaki Shimada Robert Whittier Takashi Ishibashi Masahiro Sakamoto Masao Mori Chihiro Kondo Yasuko Honji Chong-Rong Sun Bing-Yuan Meng Yu-Qing Li Akira Kanno Yoko Nishizawa Atsushi Hirai Kazuo Shinozaki Masahiro Sugiura 《Molecular & general genetics : MGG》1989,217(2-3):185-194
Summary The entire chloroplast genome of the monocot rice (Oryza sativa) has been sequenced and comprises 134525 bp. Predicted genes have been identified along with open reading frames (ORFs) conserved
between rice and the previously sequenced chloroplast genomes, a dicot, tobacco (Nicotiana tabacum), and a liverwort (Marchantia polymorpha). The same complement of 30 tRNA and 4 rRNA genes has been conserved between rice and tobacco. Most ORFs extensively conserved
betweenN. tabacum andM. polymorpha are also conserved intact in rice. However, several such ORFs are entirely absent in rice, or present only in severely truncated
form. Structural changes are also apparent in the genome relative to tobacco. The inverted repeats, characteristic of chloroplast
genome structure, have expanded outward to include several genes present only once per genome in tobacco and liverwort and
the large single copy region has undergone a series of inversions which predate the divergence of the cereals. A chimeric
tRNA pseudogene overlaps an apparent endpoint of the largest inversion, and a model invoking illegitimate recombination between
tRNA genes is proposed which accounts simultaneously for the origin of this pseudogene, the large inversion and the creation
of repeated sequences near the inversion endpoints. 相似文献
2.
Spatial proximity of the glycine-rich loop and the SH2 thiol in myosin subfragment 1 总被引:1,自引:0,他引:1
Subfragment 1 (S1) prepared from rabbit skeletal muscle myosin was digested with trypsin to cleave the 95K heavy chain into three pieces, i.e., the 23K, 50K, and 20K fragments. The trypsin-treated S1 was then cross-linked with p-nitrophenyl iodoacetate. The cross-linker bridged one of the reactive thiols (SH2) in the 20K fragment and a lysine residue in the 23K fragment [Hiratsuka, T. (1987) Biochemistry 26, 3168-3173]. Location of the lysine residue was mapped along the 23K fragment by "end-label fingerprinting", which employed site-directed antibodies against the N-terminus of the 23K fragment and against the C-terminus of the 24K fragment (the 23K fragment plus nine extra residues at its C-terminus). The mapping revealed that Lys-184 or Lys-189 was the residue cross-linked with SH2. Since the cross-linker used here spans only several angstroms, the result indicates that Lys-184 or Lys-189 is very close to SH2 in the three-dimensional structure of myosin head. Examination of the primary structure of the 23K fragment has revealed that these lysine residues are in and very close to the so-called "glycine-rich loop", whose sequence is highly homologous to those of nucleotide-binding sites of various nucleotide-binding proteins. 相似文献
3.
T Watabe A Hiratsuka K Ogura 《Biochemical and biophysical research communications》1986,134(1):100-105
Potent mutagenicity of 7,12-dihydroxymethylbenz[a]anthracene (DHBA) toward Salmonella typhimurium TA 98 in the presence of rat liver cytosol fortified with 3'-phosphoadenosine 5'-phosphosulfate (PAPS) was completely retarded by the addition of glutathione (GSH). The reactive and intrinsically mutagenic metabolite, DHBA 7-sulfate, formed by hepatic cytosolic sulfotransferase disappeared from the incubation mixture by the addition of GSH. Non-mutagenic S-(12-hydroxymethylbenz[a]anthracen-7-yl)methylglutathione was isolated from the incubation mixture consisting of the hepatic cytosol, DHBA, PAPS, and GSH and proved to be formed by GSH S-transferase directly from DHBA 7-sulfate as an obligatory intermediate. 相似文献
4.
T Watabe A Hiratsuka K Ogura K Endoh 《Biochemical and biophysical research communications》1985,131(2):694-699
The carcinogen, 7,12-dihydroxymethylbenz[alpha]anthracene (DHBA), was regioselectively conjugated in the presence of 3'-phosphoadenosine 5'-phosphosulfate by male rat liver cytosolic sulfotransferase to DHBA 7-sulfate. The sulfate ester was highly reactive and showed a potent, intrinsic mutagenicity toward Salmonella typhimurium TA 98. 相似文献
5.
Establishment of five human myeloma cell lines 总被引:3,自引:0,他引:3
Masayoshi Namba Takemi Ohtsuki Masaharu Mori Atsushi Togawa Hideho Wada Takashi Sugihara Yoshihito Yawata Tetsuo Kimoto 《In vitro cellular & developmental biology. Plant》1989,25(8):723-729
Summary Five human myeloma cell lines, KMM-1, KMS-5, KMS-11, KMS-12- PE, and KMS-12-BM, have been established at Kawasaki Medical
School since 1980. As the KMS-12-PE and KMS-12-BM lines were obtained from the same patient, these five cell lines have been
derived from four patients with multiple myeloma. The five myeloma cell lines are stably growing at present in RPMI 1640 medium
supplemented with 10% fetal bovine serum. They can also grow in a defined culture medium without serum. That these cell lines
were, human myeloma cells was confirmed by the following findings. Ultranstructually, all five cell lines showed features
characteristic of plasma cells. KMM-1 and KMS-11 cells secreted lambda and kappa chains into the culture medium, respectively,
but the other cell lines produced no immunoglobulins. KMM-1 expressed cytoplasmic lambda antigen, KMS-5 showed cytoplasmic
delta, and KMS-11 expressed surface kappa, whereas KMS-12-PE and KMS-12-BM cells showed no surface or cytoplasmic immunoglobulins.
Regarding reaction with a monoclonal plasma cell antibody (PCA-1), four of the five lines were positive, the exception being
KMS-5. Another monoclonal antibody (CD38), which also recognizes plasma cells, reponded to KMM-1, KMS-12-PE, and KSM-12-BM.
KMS-5 cells expressed acute lymphoblastic leukemia antigens (CALLA). These data suggest that such lines as KMM-1, KMS-11,
KMS-12-PE, and KMS-12-BM represent later stages of B-cell differentiation, and that KMS-5 represents a relatively early stage
of B-cell differentiation. All the cell lines lacked Epstein-Barr virus nuclear antigen, showed abnormal karyotypes of human
origin, and differed from each other in the isozyme patterns examined. Only KMS-5 was tumorigenic when transplanted subcutaneously
into nude mice. 相似文献
6.
Makoto Suematsu Shigenari Houzawa Soichiro Miura Hiroshi Nagata Tetsuji Kitahora Tetsuo Morishita Chikara Oshio Masaharu Tsuchiya 《Luminescence》1989,4(1):531-534
Reaction difference of oxyradical generation and luminol-dependent photoemission of zymosan- and phorbol ester-treated neutrophils were investigated using a conventional photomultiplier and ultrasensitive photonic imaging technique. Zymosan-treated cells released a concentrated photonic burst corresponding to the cellular distribution. In contrast, phorbol ester-treated cells produced a negligible level of photoemission, and the additional application of Ca2+ ionophore enhanced the photonic burst, which was gradually spread out into extracellular space. Serine protease inhibitors did not attenuate PMA-induced chemiluminescence but did attenuate zymosan-induced chemiluminescence. This suggests the involvement of serine protease in the respiratory burst of phagocytizing neutrophils. 相似文献
7.
I Miki T Shimizu Y Seyama S Kitamura K Yamaguchi H Sano H Ueno A Hiratsuka T Watabe 《The Journal of biological chemistry》1989,264(10):5799-5805
(11S,12S)-Epoxy-5,14-cis-7,9-trans-eicosatetraenoic acid (11,12-leukotriene A4) was nonenzymically converted to seven compounds: two diastereomers of (12S)-hydroxyeicosatetraeno-delta-lactones (major products), two diastereomers of (5,12S)-dihydroxyeicosatetraenoic acid and three stereoisomers of (11,12S)-dihydroxyeicosatetraenoic acid. Among these compounds, (11R,12S)-dihydroxy-5,14-cis-7,9-trans-eicosatetraenoic acid proved to be the only enzymic product. This hydrolysis activity was present in the cytosol fractions of various tissues of guinea pig such as liver, adrenal gland, small intestine, and brain. We purified the epoxide hydrolase to an apparent homogeneity from the guinea pig liver. The enzyme had a molecular weight of 60,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and an isoelectric point of 7.3. The partial amino acid sequence was different from that of the microsomal enzyme. Km and Vmax values for 11,12-leukotriene A4 were 18 microM and 2.4 mumol/min/mg protein, respectively. These results indicate that 11,12-dihydroxyeicosatetraenoic acid is enzymically synthesized from 11,12-leukotriene A4 by the action of the cytosolic epoxide hydrolase in vitro. 相似文献
8.
Akihiro Kinoshita Tomoo Tamura Chiharu Aoki Tohru Nakanishi Shizuo Sobue Fujio Suzuki Kojiro Takahashi Masaharu Takigawa 《Cell biology international》1995,19(8):647-654
Endothelin (ET) receptors on chondrocytes were demonstrated using cultured rabbit costal chondrocytes. After crosslinking the receptors on the cells with 125 I-ET-1, two major bands of 43 kDa and 46 kDa were separated by SDS-PAGE. Scatchard analysis demonstrated two classes of ET receptors with Kd values of 1 × 10?10 M and 5 × 10?9 M. The numbers of high- and low- affinity receptors were 1 × 104 and 2 × 105 per cell, respectively. The binding of ET-1 to chondrocytes was increased by treatment with PTH, DBcAMP, TGF-β1, IL-1β, RA and EGF. ET-1 stimulated DNA synthesis in cultured rabbit chondrocytes. ET-1 also stimulated calcium incorporation through the cell membrane of chondrocytes. These findings indicate that ET-1 has a physiological effect on chondrocytes via its receptors on the cells. 相似文献
9.
Masaharu Inouye Yoshio Takada Naoki Muto Teruhiko Beppu Sueharu Horinouchi 《Molecular genetics and genomics : MGG》1994,245(4):456-464
A 29 kb shuttle cosmid vector, pTYS507, was constructed from a cryptic Micromonospora griseorubida plasmid and the Escherichia coli cosmid pJB8. Subcloning of mycinamicin II biosysnthesis genes in pTYS507 led to the identification of a DNA region that could complement a mutant of M. griseorubida that lacked both hydroxylase and epoxidase activities. Nucleotide sequence and mutational analysis suggested that a single P-450-like protein catalyzes both reactions. 相似文献
10.
Records of exotic turbellarian species found in Japan are reviewed from taxonomic and karyological viewpoints. Temnocephala minor Haswell, 1888, an ectocommensal on a freshwater crayfish of Australia, was found from culture ponds of Cherax tenuimanus (introduced from W. Australia) in Kagoshima Prefecture. T. minor had the chromosome number of 2x = 18 (2sm + 2m + 2m + 2sm + 2m + 2m + 2m + 2sm + 2m). The following 3 species of exotic freshwater triclads were recorded from tanks and ponds used for tropical fish culture: Dugesia austroasiatica Kawakatsu, 1985 (2x = 16), Dugesia tigrina (Girard, 1850) (2x = 16) and Rhodax? sp. (3x = 24; 3x = 24 &; 3x + 1LB + 1SB = 25 + 1SB). The following 3 species of exotic terrestrial triclads were recorded: Bipalium nobile Kawakatsu et Makino, 1982 (2x = 10), Bipalium kewense Moseley, 1878 (2x = 18), and Platydemus manokwari de Beauchamp, 1962 (n = 6, 2x = 12). An extensive occurrence of P. manokwari in the Southwest Islands of Japan may be due to an unexpected introduction of the animal in very recent years. 相似文献