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21.
Hirofumi Fukushima Shigenobu Umeki Takehito Watanabe Yoshinori Nozawa 《Biochemical and biophysical research communications》1982,105(2):502-508
With the use of detergents and successive column chromatographies, Tetrahymena b-type cytochrome was purified from microsomes to a specific content of 36.0 nmol per mg of protein. The purified form showed a single band on SDS-polyacrylamide gel with molecular weight of 22,000. The spectral properties of the reduced b-type cytochrome, the α-peak of which is situated at 560 nm and asymmetric with a shoulder at 556 nm, was different from that of rat liver microsomal cytochrome b5. However, it was reducible by NADH in the presence of NADH-cytochrome b5 reductase purified from rat liver microsomes.The results indicated that the microsomal b-type cytochrome should be designated as cytochrome b5 of a ciliated protozoan, Tetrahymena pyriformis. 相似文献
22.
Hirofumi Tachibana Koichi Akiyama Sanetaka Shirahata Hiroki Murakami 《Cytotechnology》1991,6(3):219-226
The HB4C5 and HF10B4 cell lines are human-human hybridomas producing human IgM monoclonal antibodies (MAbs) reactive to porcine carboxypeptidase A (CPase), but not to double stranded DNA (ds DNA). We obtained G418-resistant HB4C5 and HF10B4 cells by an introduction of pSV2-neo DNA. Almost all of the G418-resistant clones produced MAbs reactive to not only the CPase but the ds DNA. The results of the inhibition ELISA suggested that the cross-reactivity of the antibodies from G418-resistant clones to CPase and ds DNA was responsible for the alteration on their antigen specificity. HB4C5 and HF10B4 cells and their G418-resistant clones produced antibodies having glycosylated chain. The antibodies produced by tunicamycin-treated G418-resistant subclones of HB4C5 and HF10B4 lost the ability to bind to ds DNA, but retained the ability to bind to CPase. These results suggest that an introduction of pSV2-neo DNA into these hybridomas alters the specificities of their MAbs, and that the alteration to antigen binding specificities of their MAbs may be associated with glycosylation of the MAbs by these hybridomas. 相似文献
23.
Hirofumi Uchimiya S. G. Wildman 《In vitro cellular & developmental biology. Plant》1979,15(6):463-468
Summary The nuclei and cytoplasm ofN. gossei andN. tabacum are compatible to the extent that reciprocal, interspecific F1 hybrids can be produced by conventional breeding techniques. Conditions were established in which manyN. gossei isolated chloroplasts could be seen by phase and fluorescence microscopy to adhere to 40% of the population of protoplasts
obtained from white tissue of variegatedN. tabacum plants and to remain attached after washing the protoplasts. Chloroplasts also could be seen to enter the interior of the
protoplasts. After treating albino protoplasts withN. gossei chloroplasts, the protoplasts were subjected to further conditions whereby 65 calluses containing shoots developed. TwentyN. tabacum protoplasts not treated with foreign chloroplasts also produced calluses with shoots to serve as a control. All calluses
developed chlorophyll irrespective of whether or not the albino protoplasts had been treated with isolatedN. gossei chloroplasts. The Fraction 1 protein ofN. tabacum has a different electrophoretic mobility from the protein ofN. gossei or anN. gossei xN. tabacum F1 hybrid. The Fraction 1 protein large subunit is coded by chloroplast DNA, whereas the small subunit is coded by nuclear DNA.
Fraction 1 protein was isolated from the variegated shoots of the 65 calluses obtained after treating albino protoplasts with
foreign chloroplasts. Immunoelectrophoresis demonstrated the protein from each callus to have a mobility identical toN. tabacum protein. Therefore, under circumstances highly favorable for the direct transfer ofN. gossei isolated chloroplasts (and possibly nuclei also) intoN. tabacum protoplasts, no evidence was obtained to suggest that genetic information contained in the isolated foreign organelles was
being translated into the polypeptides of either the large or small subunits of Fraction 1 protein contained in newly differentiated
leaves derived from the protoplasts.
Supported by Research Grant PCM-75-07368 from the National Science Foundation. 相似文献
24.
Chloroplasts isolated from dark-grown seedlings of Picea abiesshowed activities of DCIP and Fecy photoreductions widiout additionof an electron donor to PS-II. In addition to this, when light-inducedoxygen evolution was measured with an oxygen electrode, a significantamount of oxygen was found. These results indicate that thephotoreductions are coupled to the oxygen-evolving reaction.Furthermore, thylakoid membranes were functional in the protonuptake and the 515-nm absorbance change as parameters of theirphysicochemical functions. Electron microscopy showed that thylakoidswere well-developed with prolamellar bodies and partially stackedto from grana. We conclude that oxygen-evolving ability and the physicochemicalfunction of thylakoid membranes develop in chloroplasts of dark-grownspruce seedlings. (Received September 21, 1974; ) 相似文献
25.
26.
Role of salicylic acid glucosyltransferase in balancing growth and defence for optimum plant fitness
27.
Natsuki Osaka Yu kanesaki Megumi Watanabe Satoru Watanabe Taku Chibazakura Hiraku Takada Hirofumi Yoshikawa Kei Asai 《Molecular microbiology》2020,113(6):1155-1169
In bacteria, guanosine (penta)tetra-phosphate ([p]ppGpp) is essential for controlling intracellular metabolism that is needed to adapt to environmental changes, such as amino acid starvation. The (p)ppGpp0 strain of Bacillus subtilis, which lacks (p)ppGpp synthetase, is unable to form colonies on minimal medium. Here, we found suppressor mutations in the (p)ppGpp0 strain, in the purine nucleotide biosynthesis genes, prs, purF and rpoB/C, which encode RNA polymerase core enzymes. In comparing our work with prior studies of ppGpp0 suppressors, we discovered that methionine addition masks the suppression on minimal medium, especially of rpoB/C mutations. Furthermore, methionine addition increases intracellular GTP in rpoB suppressor and this effect is decreased by inhibiting GTP biosynthesis, indicating that methionine addition activated GTP biosynthesis and inhibited growth under amino acid starvation conditions in (p)ppGpp0 backgrounds. Furthermore, we propose that the increase in intracellular GTP levels induced by methionine is due to methionine derivatives that increase the activity of the de novo GTP biosynthesis enzyme, GuaB. Our study sheds light on the potential relationship between GTP homeostasis and methionine metabolism, which may be the key to adapting to environmental changes. 相似文献
28.
29.
Kanno Yosuke Shu En Niwa Hirofumi Seishima Mariko Ozaki Kei-ichi 《Molecular biology reports》2021,48(4):3431-3437
Molecular Biology Reports - Systemic sclerosis (SSc) is characterized by peripheral circulatory disturbance and fibrosis in skin and visceral organs. We recently demonstrated that... 相似文献
30.
Hirofumi Uyama Michiko Mandai Masayo Takahashi 《Development, growth & differentiation》2021,63(1):59-71
Various advances have been made in the treatment of retinal diseases, including new treatment strategies and innovations in surgical devices. However, the treatment of degenerative retinal diseases, such as retinitis pigmentosa (RP) and age‐related macular degeneration (AMD), continues to pose a significant challenge. In this review, we focus on the use of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) to treat retinal diseases by harnessing the ability of stem cells to differentiate into different body tissues. The retina is a tissue specialized for light sensing, and its degradation leads to vision loss. As part of the central nervous system, the retina has very low regenerative capability, and therefore, treatment options are limited once it degenerates. Nevertheless, innovations in methods to induce the generation of retinal cells and tissues from ESCs/iPSCs enable the development of novel approaches for these irreversible diseases. Here we review some historical background and current clinical trials involving the use of stem‐cell‐derived retinal pigment epithelial cells for AMD treatment and stem cell‐derived retinal cells/tissues for RP therapy. Finally, we discuss our future vision of regenerative treatment for retinal diseases with a partial focus on our studies and introduce other interesting approaches for restoring vision. 相似文献