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101.
Masahiko Ishida Hideo Nagayama Kensuke Shimura 《Bioscience, biotechnology, and biochemistry》2013,77(8):1881-1892
The biosynthetic pathway of vitamin B6 (abbreviated as Be) has been studied with the cell-suspension of B6-producing bacteria, Achromobacter cycloclastes A.M.S. 6201. The distribution of 14C in the Be molecule prepared with the cell-suspensions containing glycerol-1,3-14C, glycerol-2-14C or γ-aminobutyric acid-U-14C was investigated by using three novel degradation methods. The results showed that carbon skeletons of glycerol and γ-aminobutyric acid were used for the formation of the major part of B6 carbon skeleton respectively. The implication of these compounds as precursors of B6 was discussed. 相似文献
102.
Satoshi Fujita Jaromir Pytela Takashi Hotta Takehide Kato Takahiro Hamada Rie Akamatsu Yasumasa Ishida Natsumaro Kutsuna Seiichiro Hasezawa Yuko Nomura Hirofumi Nakagami Takashi Hashimoto 《Current biology : CB》2013,23(20):1969-1978
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103.
Zhongwei Zou Masahiko Ishida Feng Li Tomohiro Kakizaki Sho Suzuki Hiroyasu Kitashiba Takeshi Nishio 《PloS one》2013,8(1)
SNP markers for QTL analysis of 4-MTB-GSL contents in radish roots were developed by determining nucleotide sequences of bulked PCR products using a next-generation sequencer. DNA fragments were amplified from two radish lines by multiplex PCR with six primer pairs, and those amplified by 2,880 primer pairs were mixed and sequenced. By assembling sequence data, 1,953 SNPs in 750 DNA fragments, 437 of which have been previously mapped in a linkage map, were identified. A linkage map of nine linkage groups was constructed with 188 markers, and five QTLs were detected in two F2 populations, three of them accounting for more than 50% of the total phenotypic variance being repeatedly detected. In the identified QTL regions, nine SNP markers were newly produced. By synteny analysis of the QTLs regions with Arabidopsis thaliana and Brassica rapa genome sequences, three candidate genes were selected, i.e., RsMAM3 for production of aliphatic glucosinolates linked to GSL-QTL-4, RsIPMDH1 for leucine biosynthesis showing strong co-expression with glucosinolate biosynthesis genes linked to GSL-QTL-2, and RsBCAT4 for branched-chain amino acid aminotransferase linked to GSL-QTL-1. Nucleotide sequences and expression of these genes suggested their possible function in 4MTB-GSL biosynthesis in radish roots. 相似文献
104.
Taku Fukuzawa Junji Ishida Akira Kato Taro Ichinose Donna Maretta Ariestanti Tomoya Takahashi Kunitoshi Ito Jumpei Abe Tomohiro Suzuki Shigeharu Wakana Akiyoshi Fukamizu Nobuhiro Nakamura Shigehisa Hirose 《PloS one》2013,8(7)
Lung surfactant is a complex mixture of lipids and proteins, which is secreted from the alveolar type II epithelial cell and coats the surface of alveoli as a thin layer. It plays a crucial role in the prevention of alveolar collapse through its ability to reduce surface tension. Under normal conditions, surfactant homeostasis is maintained by balancing its release and the uptake by the type II cell for recycling and the internalization by alveolar macrophages for degradation. Little is known about how the surfactant pool is monitored and regulated. Here we show, by an analysis of gene-targeted mice exhibiting massive accumulation of surfactant, that Ig-Hepta/GPR116, an orphan receptor, is expressed on the type II cell and sensing the amount of surfactant by monitoring one of its protein components, surfactant protein D, and its deletion results in a pulmonary alveolar proteinosis and emphysema-like pathology. By a coexpression experiment with Sp-D and the extracellular region of Ig-Hepta/GPR116 followed by immunoprecipitation, we identified Sp-D as the ligand of Ig-Hepta/GPR116. Analyses of surfactant metabolism in Ig-Hepta+/+ and Ig-Hepta−/− mice by using radioactive tracers indicated that the Ig-Hepta/GPR116 signaling system exerts attenuating effects on (i) balanced synthesis of surfactant lipids and proteins and (ii) surfactant secretion, and (iii) a stimulating effect on recycling (uptake) in response to elevated levels of Sp-D in alveolar space. 相似文献
105.
Asako Saiki Yasuaki Ishida Ryuichi Hirota Takeshi Nakamura Akio Kuroda 《Bioscience, biotechnology, and biochemistry》2016,80(5):955-961
Inorganic polyphosphate (polyP) was previously identified as a probiotic-derived substance that enhances intestinal barrier function. PolyP-accumulating bacteria are expected to have beneficial effects on the human gastrointestinal tract. In this study, we selected Lactobacillus paracasei JCM 1163 as a strain with the potential to accumulate polyP, because among the probiotic bacteria stored in our laboratory, it had the largest amount of polyP. The chain length of polyP accumulated in L. paracasei JCM 1163 was approximately 700 phosphate (Pi) residues. L. paracasei JCM 1163 accumulated polyP when Pi was added to Pi-starved cells. We further improved the ability of L. paracasei JCM 1163 to accumulate polyP by nitrosoguanidine mutagenesis. The mutant accumulated polyP at a level of 1500 nmol/mg protein—approximately 190 times that of the wild-type strain. PolyP extracted from the L. paracasei JCM 1163 significantly suppressed the oxidant-induced intestinal permeability in mouse small intestine. In conclusion, we have succeeded in breeding the polyP-accumulating Lactobacillus mutant that is expected to enhance intestinal barrier function. 相似文献
106.
Masatsugu Miyara Kanae Umeda Keishi Ishida Seigo Sanoh Shigeru Ohta 《Bioscience, biotechnology, and biochemistry》2016,80(6):1164-1167
Serum is an important component of cell culture media. The present study demonstrates contamination of intracellular protein extract by bovine serum albumin from the culture media and illustrates how this contamination can cause the misinterpretation of western blot results. Preliminary experiments can prevent the misinterpretation of some experimental results, and optimization of the washing process may enable specific protein detection. 相似文献
107.
Tsubasa Ishida Rie Ito Jessica Clark Nicholas J. Matzke Yoshiyuki Sowa Matthew A. B. Baker 《Molecular microbiology》2019,111(6):1689-1699
The bacterial flagellar motor powers the rotation that propels the swimming bacteria. Rotational torque is generated by harnessing the flow of ions through ion channels known as stators which couple the energy from the ion gradient across the inner membrane to rotation of the rotor. Here, we used error‐prone PCR to introduce single point mutations into the sodium‐powered Vibrio alginolyticus/Escherichia coli chimeric stator PotB and selected for motors that exhibited motility in the presence of the sodium‐channel inhibitor phenamil. We found single mutations that enable motility under phenamil occurred at two sites: (i) the transmembrane domain of PotB, corresponding to the TM region of the PomB stator from V. alginolyticus and (ii) near the peptidoglycan binding region that corresponds to the C‐terminal region of the MotB stator from E. coli. Single cell rotation assays confirmed that individual flagellar motors could rotate in up to 100 µM phenamil. Using phylogenetic logistic regression, we found correlation between natural residue variation and ion source at positions corresponding to PotB F22Y, but not at other sites. Our results demonstrate that it is not only the pore region of the stator that moderates motility in the presence of ion‐channel blockers. 相似文献
108.
Gliclazide inhibits proliferation but stimulates differentiation of white and brown adipocytes 总被引:1,自引:0,他引:1
Nakano N Miyazawa N Sakurai T Kizaki T Kimoto K Takahashi K Ishida H Takahashi M Suzuki K Ohno H 《Journal of biochemistry》2007,142(5):639-645
Gliclazide, a second-generation sulfonylurea, has anti-oxidant properties as well as hypoglycemic activities. In the present study, we investigated whether gliclazide affected proliferation and/or differentiation of HW white and HB2 brown adipocyte cell lines. Gliclazide inhibited proliferation of HW and HB2 cells in the medium containing fetal calf serum or epidermal growth factor (EGF). Gliclazide inhibited phosphorylation of EGF receptor and of extracellular signal-regulated kinase (ERK) 1/2 stimulated by EGF. Gliclazide increased lipid accumulation and peroxisome proliferator-activated receptor gamma (PPARgamma) expression in the early stage of differentiation of adipocytes. A K(ATP) channel activator, diazoxide, did not inhibit the increase of lipid accumulation by gliclazide. Furthermore, gliclazide inhibited the DNA-binding activity of PPARgamma in mature adipocytes. On the other hand, glibenclamide, other sulfonylurea, did not show these effects. These results indicate gliclazide inhibits proliferation and stimulates differentiation of adipocytes via down-regulation of the EGFR signalling. Gliclazide may have preventive and therapeutic effects on obesity, as well as on type 2 diabetes. 相似文献
109.
Takeda N Maemura K Horie S Oishi K Imai Y Harada T Saito T Shiga T Amiya E Manabe I Ishida N Nagai R 《The Journal of biological chemistry》2007,282(45):32561-32567
Cardiovascular diseases are closely related to circadian rhythm, which is under the control of an internal biological clock mechanism. Although a biological clock exists not only in the hypothalamus but also in each peripheral tissue, the biological relevance of the peripheral clock remains to be elucidated. In this study we searched for clock-controlled genes in vascular endothelial cells using microarray technology. The expression of a total of 229 genes was up-regulated by CLOCK/BMAL2. Among the genes that we identified, we examined the thrombomodulin (TM) gene further, because TM is an integral membrane glycoprotein that is expressed primarily in vascular endothelial cells and plays a major role in the regulation of intravascular coagulation. TM mRNA and protein expression showed a clear circadian oscillation in the mouse lung and heart. Reporter analyses, gel shift assays, and chromatin immunoprecipitation analyses using the TM promoter revealed that a heterodimer of CLOCK and BMAL2 binds directly to the E-box of the TM promoter, resulting in TM promoter transactivation. Indeed, the oscillation of TM gene expression was abolished in clock mutant mice, suggesting that TM expression is regulated by the clock gene in vivo. Finally, the phase of circadian oscillation of TM mRNA expression was altered by temporal feeding restriction, suggesting TM gene expression is regulated by the peripheral clock system. In conclusion, these data suggest that the peripheral clock in vascular endothelial cells regulates TM gene expression and that the oscillation of TM expression may contribute to the circadian variation of cardiovascular events. 相似文献
110.
Yoshimasa Takafuji Kohei Tatsumi Masayoshi Ishida Naoyuki Kawao Kiyotaka Okada Osamu Matsuo Hiroshi Kaji 《Journal of cellular physiology》2019,234(6):9687-9697
Plasminogen activator inhibitor-1 (PAI-1) is known as an inhibitor of fibrinolytic system. Previous studies suggest that PAI-1 is involved in the pathogenesis of osteoporosis induced by ovariectomy, diabetes, and glucocorticoid excess in mice. However, the roles of PAI-1 in early-stage osteogenic differentiation have remained unknown. In the current study, we investigated the roles of PAI-1 in osteoblastic differentiation of mesenchymal stem cells (MSCs) using wild-type (WT) and PAI-1-deficient (PAI-1 KO) mice. PAI-1 mRNA levels were increased with time during osteoblastic differentiation of MSCs or mesenchymal ST-2 cells. However, the increased PAI-1 levels declined at the mineralization phase in the experiment using MC3T3-E1 cells. PAI-1 deficiency significantly blunted the expression of osteogenic gene, such as osterix and alkaline phosphatase enhanced by bone morphogenetic protein (BMP)-2 in bone marrow-derived MSCs (BM-MSCs), adipose-tissue-derived MSCs (AD-MSCs), and bone marrow stromal cells of mice. Moreover, a reduction in endogenous PAI-1 levels by small interfering RNA significantly suppressed the expression of osteogenic gene in ST-2 cells. Plasmin did not affect osteoblastic differentiation of AD-MSCs induced by BMP-2 with or without PAI-1 deficiency. PAI-1 deficiency and a reduction in endogenous PAI-1 levels did not affect the phosphorylations of receptor-specific Smads by BMP-2 and transforming growth factor-β in AD-MSCs and ST-2 cells, respectively. In conclusion, we first showed that PAI-1 is crucial for the differentiation of MSCs into osteoblasts in mice. 相似文献