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41.
Successful expression in pollen of various plant species of in vitro synthesized mRNA introduced by particle bombardment 总被引:5,自引:0,他引:5
Toshinori Tanaka Masahiro Nishihara Motoaki Seki Atsushi Sakamoto Kunisuke Tanaka Kohei Irifune Hiromichi Morikawa 《Plant molecular biology》1995,28(2):337-341
Gold particles coated with -glucuronidase (GUS) mRNA with a 5 cap structure that had been synthesized in vitro were introduced, by use of a pneumatic particle gun, into pollen grains of lily (Lilium longiflorum), freesia (Freesia refracta) and tulip (Tulipa gesneriana). A fluorometric assay for the GUS activity indicated that in vitro synthesized GUS mRNA introduced into these pollen cells by particle bombardment was successfully expressed. GUS activity in extracts of the bombarded lily pollen became detectable fluorometrically within 30 min after bombardment, peaked at 6 h, then gradually decreased. This activity changed as a function of the developmental stage of the pollen cell of lily. 相似文献
42.
Rika Morishita Shinsuke Saga Noriko Kawamura †Yoshio Hashizume ‡Toshiaki Inagaki Kanefusa Kato Tomiko Asano 《Journal of neurochemistry》1997,68(2):820-827
Abstract: The localization of two forms of the γ subunit of G proteins, γ3 and γ12, was examined in the mammalian brain. Concentrations of these two γ subunits increased markedly, as did those of glial fibrillary acidic protein, during postnatal development in the rat cerebral cortex. In aged human brains, by contrast, the concentration of γ3 tended to decrease with age, whereas that of γ12 in the temporal cortex increased slightly. An immunohistochemical study of human brains revealed that γ3 was abundant in the neuropil, whereas γ12 was localized in glial cells. In the hippocampal formation of aged human brains, levels of γ12-positive cells, as well as levels of glial fibrillary acidic protein- and vimentin-positive astrocytes, increased, in particular in the CA1 subfield and the prosubiculum, in which there was a decrease in the number of pyramidal cells. The appearance of γ12-positive cells associated with the loss of pyramidal cells was also observed in the hippocampus of rats that had been treated with kainic acid. These results indicate that γ12 is strongly expressed in reactive astrocytes. In a study of cultured neural cells, we found that γ12 was predominant in glioma cells, such as C6 and GA-1 cells, in contrast with the specific localization of γ3 in PC12 pheochromocytoma cells, which are neuron-like cells. Taken together, the results indicate that γ3 and γ12 are selectively expressed in neuronal and glial cells, respectively, and that concentrations of γ3 and γ12 in the brain are related to the numbers and/or extent of maturation of these cells. 相似文献
43.
Leying Wen Hiroshi Ushijima Junko Kakizawa Zhao-Yin Fang Osamu Nishio Shigeru Morikawa Takashi Motohiro 《Microbiology and immunology》1995,39(11):911-915
Sequence analysis of the gene encoding the major neutralization glycoprotein (VP7) was performed on sixteen human isolates of serotype 2 of rotavirus in Japan, China, and Pakistan and their genetic variations were examined. Comparative studies of their nucleotide and deduced amino acid sequences between the sixteen isolates and the HU5 strain revealed an overall homology of more than 94%. A higher degree of homology in nucleotides was observed among the sixteen isolates than between HU5 and the isolates. A total of thirteen amino acid residues frequently converted to another amino acid. Out of the thirteen, five amino acid residues belonging to the major neutralizing epitope regions (C, E, and F in this communication) converted frequently. From the amino acid sequences three subtypes, subtype 1, subtype 2, and intermediate, were suggested to be classified as previously reported for serotype 1 (Xin et al, Virology, 1993, 197: 813-816). 相似文献
44.
Phylogeny of symbiotic methanogens in the gut of the termite Reticulitermes speratus 总被引:3,自引:0,他引:3
Abstract The phylogeny of a symbiotic methanogen inhabiting the gut of a lower termite, Reticulitermes speratus , was analysed without cultivation. The small subunit ribosomal RNA gene (ssrDNA) and a 640-bp portion of the gene encoding subunit A of methyl coenzyme M reductase ( mcrA ) were amplified from a mixed-population DNA of the termite gut by polymerase chain reaction and cloned. The nucleotide sequence of the ssrDNA and the predicted amino acid sequence of the mcrA product were compared with those of the known methanogens. Both comparisons indicated that the termite symbiotic methanogen belonged to the order Methanobacteriales but was distinct from the known members of this order. 相似文献
45.
Souichi Morikawa Kazuhiro Ogata Ai Sekikawa Akinori Sarai Shunsuke Ishii Yoshifumi Nishimura Haruki Nakamura 《Journal of biomolecular NMR》1995,6(3):294-305
Summary The solution structure of a specific DNA complex of the minimum DNA-binding domain of the mouse c-Myb protein was determined by distance geometry calculations using a set of 1732 nuclear Overhauser enhancement (NOE) distance restraints. In order to determine the complex structure independent of the initial guess, we have developed two different procedures for the docking calculation using simulated annealing in four-dimensional space (4D-SA). One is a multiple-step procedure, where the protein and the DNA were first constructed independently by 4D-SA using only the individual intramolecular NOE distance restraints. Here, the initial structure of the protein was a random coil and that of the DNA was a typical B-form duplex. Then, as the starting structure for the next docking procedure, the converged protein and DNA structures were placed in random molecular orientations, separated by 50 Å. The two molecules were docked by 4D-SA utilizing all the restraints, including the additional 66 intermolecular distance restraints. The second procedure comprised a single step, in which a random-coil protein and a typical B-form DNA duplex were first placed 70 Å from each other. Then, using all the intramolecular and intermolecular NOE distance restraints, the complex structure was constructed by 4D-SA. Both procedures yielded the converged complex structures with similar quality and structural divergence, but the multiple-step procedure has much better convergence power than the single-step procedure. A model study of the two procedures was performed to confirm the structural quality, depending upon the number of intermolecular distance restraints, using the X-ray structure of the engrailed homeodomain-DNA complex.Abbreviations rmsd
root-mean-square deviation
- NOE
nuclear Overhauser enhancement
- 4D-SA
simulated annealing in four-dimensional space
- Myb-R2R3
repeats 2 and 3 of the DNA-binding domain of the c-Myb protein
- DNA 16
Myb-specific binding DNA duplex with 16 base pairs
- IHDD-C
residues 3 to 59 of the C-chain of the engrailed homeodomain-DNA complex
- DNA11
DNA duplex with base pairs 9 to 19 of the engrailed homeodomain-DNA complex 相似文献
46.
Yoshisada Fujiwara Toshiaki Higashikawa Mariko Tatsumi 《Journal of cellular physiology》1977,92(3):365-374
We investigated the cloning efficiency, DNA repair, and the rate of DNA replication in the skin fibroblasts from patients with Werner's syndrome (WS) of an autosomal recessive premature aging disease. Five WS strains exhibited normal levels of sensitivity toward X-ray and UV killings and repair of X-ray induced single strand breaks of DNA (rejoining) and UV damage to DNA (unscheduled DNA synthesis). The sedimentation of newly synthesizing DNA in alkaline sucrose gradients demonstrated a characteristic feature that only the elongation rate of DNA chains, estimated by the molecular weight increase, was significantly slower during early passages in WS cells than in normal Hayflick Phase II fibroblasts. In addition, plating efficiencies as well as the replicative potentials of five WS strains were more limited than those of normal cells under the identical culture conditions. It seems therefore that at least in the WS cells tested, the slow rate of DNA replication may be more related to the shortened lifespan and enhanced cell death, as manifestation of premature senescence at the cellular level, than be the DNA repair ability. 相似文献
47.
Infrared analysis of pea stem cell walls and oriented structure of matrix polysaccharides in them 总被引:4,自引:0,他引:4
Infrared absorption spectra of film specimens of the epidermaland parenchyma cell walls of the third internode of pea stem,before and after protease treatment and after treatment forremoval of lipid materials, pectic substances and hemicellulose,were recorded, and characteristic bands in the spectrum of thewall were assigned. Polarization spectrum measurements of thewall provided evidence indicating that the non-cellulosic polysaccharidematrix as well as cellulose microfibrils has an oriented structurein the wall which changes during extension growth as well asupon mechanical extension of the walls. (Received March 9, 1978; ) 相似文献
48.
The increase in the dichroism of the ester-C=O and COObands in response to mechanical extension in oat coleoptilecell walls was much enhanced by IAA pretreatment while the decreasein that of the C-O-C band was not enhanced or even suppressed.The results indicate the importance of the ultrastructure ofnon-cellulosic polysaccharides in controlling auxin-inducedcell elongation.
1 Present adress: Department of Agricultural Chemistry, KyotoPrefectural University, Shimogamo, Kyoto 606, Japan. (Received May 16, 1978; ) 相似文献
49.
Toshiaki Shinohara Michael W. Thomas Ellen G. Gilliam Virginia P. Wray Earl F. Walborg 《Archives of biochemistry and biophysics》1982,219(2):411-421
Novikoff hepatocellular carcinoma cells possess cell-surface glycoproteins that bind the lectin, concanavalin A. A subset of Con A-binding plasma membrane glycoproteins was solubilized by addition of n-butanol to a suspension of Novikoff cells. Glycoproteins solubilized into the n-butanol-saturated aqueous phase of the two-phase mixture were purified by sequential chromatography on DEAE-cellulose and Sepharose-conjugated concanavalin A. Glycoproteins specifically bound to the Sepharose-conjugated Con A exhibited apparent Mr = 72,000 to 125,000. The plasma membrane localization of these components was inferred by their isolation from cells surface labeled with NaIO4/ NaB3H4. A xenoantiserum, raised against glycoproteins specifically bound to Sepharose-conjugated concanavalin A was employed to identify reactive components in nonionic detergent extracts of Novikoff tumor cells or rat hepatocytes surface labeled using lactoperoxidase-catalyzed iodination (125I). Major reactive peptides in extracts of Novikoff cells exhibited apparent Mr = 74,000, 82, 000, 110,000, and 135,000, while those in extracts of hepatocytes possessed apparent Mr = 98,000 and 105,000. The reactivity of the antiserum with extracts of 125I-labeled Novikoff cells was abolished by absorption of the antiserum with hepatocytes, indicating that the qualitative differences observed may result from structural modification of one or more cell-surface glycoproteins, rather than the expression of new or inappropriate glycoproteins. This antiserum will provide a useful probe to investigate alterations in the expression or structure of glycoproteins that occur as a consequence of malignant transformation or adaptation of malignant cells to growth in the ascitic form. 相似文献
50.
Hiroshi Kanazawa Toshiaki Kayano Tatsuya Kiyasu Masamitsu Futai 《Biochemical and biophysical research communications》1982,105(4):1257-1264
The 1855-nucleotide long DNA sequence of part of the gene cluster for the proton-translocating ATPase from was determined by the method of Maxam-Gilbert. The sequence covers the genes for the β and ε subunits of F1 along with the flanking region. The amino acid sequence of these subunits deduced from the nucleotide sequence indicates that the β and ε subunits have 459 and 138 amino acids, respectively. The possible secondary structure of the both subunits was estimated from the deduced primary structures. A possible nucleotide binding site in the β subunit is also discussed on the basis of the primary and secondary structures. The codons used in the genes for all the components of F1F0 were different in different genes, suggesting that the amount of each subunit in the F1F0 is determined to some extent on a translational level. 相似文献