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991.
Hideyuki Takahashi Hidetoshi Mizuno Motoshi Kamada Nobuharu Fujii Atsushi Higashitani Shigeki Kamigaichi Sachiko Aizawa Chiaki Mukai Toru Shimazu Keiji Fukui Masamichi Yamashita 《Journal of plant research》1999,112(4):497-505
peg , on the transition zone between hypocotyl and root. Our spaceflight experiment verified that the lateral positioning of a
peg in cucumber seedlings is modified by gravity. It has been suggested that auxin plays an important role in the gravity-controlled
positioning of a peg on the ground. Furthermore, cucumber seedlings grown in microgravity developed a number of the lateral
roots that grew towards the water-containing substrate in the culture vessel, whereas on the ground they oriented perpendicular
to the primary root growing down. The response of the lateral roots in microgravity was successfully mimicked by clinorotation
of cucumber seedlings on the three dimensional clinostat. However, this bending response of the lateral roots was observed
only in an aeroponic culture of the seedlings but not in solid medium. We considered the response of the lateral roots in
microgravity and on clinostat as positive hydrotropism that could easily be interfered by gravitropism on the ground. This
system with cucumber seedlings is thus a useful model of spaceflight experiment for the study of the gravimorphogenesis, root
hydrotropism and their interaction.
Received 13 September 1999/ Accepted in revised form 12 October 1999 相似文献
992.
Jayeesha Ghosh Yoshikatsu Akiyama Yuji Haraguchi Kumiko Yamanaka Toru Asahi Yoichi Nakao Tatsuya Shimizu 《Biotechnology progress》2024,40(1):e3402
In recent years, serum-free medium for mammalian cell cultivation has attracted a lot of attention, considering the high cost of production and environmental load involved in developing the conventional animal sera. The use of alternative growth-promoting products in mammalian cell cultivation such as extracts from microalgae has proven to be quite beneficial and environmental-friendly. This research aims to cultivate mammalian cells with growth-promoting factors derived from Chlorococcum littorale. We have established a simple extraction using the ultrasonication method and applied the extract in place of serum on mammalian C2C12 cell lines, 3T3 cell lines, and CHO cell lines to compare and analyze the effectiveness of the extract. Cell passage was conducted in a suspended culture condition with the addition of the extract. The results indicate that the extract from microalgae shows a high proliferation rate in all cell lines without fetal bovine serum. Moreover, it is eco-friendly and has huge potential to replace the traditional cell culture system. It could be applied in the fields of regenerative medicine, gene/cell therapies, as well as cultured meat production. 相似文献
993.
Amino acid analyses of nuclear basic proteins of an anuran amphibian, Rana catesbeiana, revealed that they are comprised of a full set of core histones and three types of lysine-rich, sperm-specific proteins. On the basis of their amino-acid compositions and partial amino-acid sequences of their trypsin-resistant cores, the sperm-specific proteins could be defined as members of the histone H1 family. Both micrococcal nuclease digestion and electron microscopy indicated that sperm chromatin consists of nucleosomal and fibrillar DNA structures which are irregularly interspersed with each other. When sperm nuclei were incubated with nucleoplasmin, nuclei decondensed to some extent, and the sperm-specific H1s were removed, but not completely. The residual sperm-specific histone H1 variants were also found in reconstituted male pronuclear chromatin, comprising regularly spaced nucleosomes. We conclude that sperm-specific histone H1 variants are essential for chromatin condensation in the sperm nuclei, but that their complete removal is not necessary for the remodeling into somatic chromatin that takes place after fertilization. Mol. Reprod. Dev. 47:181–190, 1997. © 1997 Wiley-Liss, Inc. 相似文献
994.
995.
Hiroki Katayama Shigeo Takahashi Takuya Kobata Akihiro Oishi Toru Shibata 《Reports of Practical Oncology and Radiotherapy》2021,26(6):906
BackgroundThe target volume increases when the prostate and pelvic lymph nodes (PLNs) are combined, and the fiducial markers (FMs) are placed at the edge of the irradiation field. Thus, the position of FMs may be changed by the rotational errors (REs) of “whole pelvis”. The aim of this study was to examine the impact of REs of “whole pelvis” on the dose of FMs-based image-guided radiotherapy to the PLNs and the small bowel in prostate cancer including the PLNs.Materials and methodsWe retrospectively evaluated 10 patients who underwent prostate cancer radiotherapy involving the PLNs. The position of FMs was calculated from the radiographs obtained before and after the 6D correction of pelvic REs. We simulated the delivery dose considering the daily pelvic REs and calculated the difference from the planned dose in the D98% of the PLN clinical target volume and the D2cc, and V45Gy of the small bowel.ResultThe position of FMs strongly correlated with the pelvic REs in the pitch direction (r = 0.7788). However, the mean delivered doses to PLNs for 10 patients were not significantly different from the planned doses (p = 0.625). Although the D2cc and V45Gy of the small bowel strongly correlated with the pitch rotation of the pelvis, there was no significant difference between the delivered and planned doses (p = 0.922 and p = 0.232, respectively).ConclusionThe dosimetric effect of pelvic REs on the dose to PLNs and the small bowel was negligible during the treatment course. 相似文献
996.
LjMOT1, a high‐affinity molybdate transporter from Lotus japonicus,is essential for molybdate uptake,but not for the delivery to nodules
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Guilan Duan Tsuneo Hakoyama Takehiro Kamiya Hiroki Miwa Fabien Lombardo Shusei Sato Satoshi Tabata Zheng Chen Toshihiro Watanabe Takuro Shinano Toru Fujiwara 《The Plant journal : for cell and molecular biology》2017,90(6):1108-1119
Molybdenum (Mo) is an essential nutrient for plants, and is required for nitrogenase activity of legumes. However, the pathways of Mo uptake from soils and then delivery to the nodules have not been characterized in legumes. In this study, we characterized a high‐affinity Mo transporter (LjMOT1) from Lotus japonicus. Mo concentrations in an ethyl methanesulfonate–mutagenized line (ljmot1) decreased by 70–95% compared with wild‐type (WT). By comparing the DNA sequences of four AtMOT1 homologs between mutant and WT lines, one point mutation was found in LjMOT1, which altered Trp292 to a stop codon; no mutation was found in the other homologous genes. The phenotype of Mo concentrations in F2 progeny from ljmot1 and WT crosses were associated with genotypes of LjMOT1. Introduction of endogenous LjMOT1 to ljmot1 restored Mo accumulation to approximately 60–70% of the WT. Yeast expressing LjMOT1 exhibited high Mo uptake activity, and the Km was 182 nm . LjMOT1 was expressed mainly in roots, and its expression was not affected by Mo supply or rhizobium inoculation. Although Mo accumulation in the nodules of ljmot1 was significantly lower than that of WT, it was still high enough for normal nodulation and nitrogenase activity, even for cotyledons‐removed ljmot1 plants grown under low Mo conditions, in this case the plant growth was significantly inhibited by Mo deficiency. Our results suggest that LjMOT1 is an essential Mo transporter in L. japonicus for Mo uptake from the soil and growth, but is not for Mo delivery to the nodules. 相似文献
997.
Yoshikazu Watanabe Kohei Hayashida Daisuke Saito Toshihiro Takahashi Junichi Sakai Eriko Nakata Takashi Kanda Takashi Iwai Shigeto Hirayama Hideaki Fujii Tomio Yamakawa Hiroshi Nagase 《Bioorganic & medicinal chemistry letters》2017,27(15):3495-3498
We designed and synthesized novel δ opioid receptor (DOR) agonists 3a–i with an azatricyclodecane skeleton, which was a novel structural class of DOR agonists. Among them, 3b exhibited high values of binding affinity and potent agonistic activity for the DOR that were approximately equivalent to those of 2 which bore an oxazatricyclodecane skeleton. In vitro assays using the blood-brain barrier (BBB) permeability test kit supported the idea that 3b achieved an excellent BBB permeability by converting an oxygen atom of 2 to a carbon atom (methylene group) in the core skeleton. As a result, 3b showed potent antinociceptive effects. 相似文献
998.
Hidefumi Yoshinaga Shuji Masumoto Koji Koyama Naoya Kinomura Yuji Matsumoto Taro Kato Satoko Baba Kenji Matsumoto Tomoko Horisawa Hitomi Oki Kazuki Yabuuchi Toru Kodo 《Bioorganic & medicinal chemistry》2017,25(1):293-304
We report the discovery of a novel benzylpiperidine derivative with serotonin transporter (SERT) inhibitory activity and 5-HT1A receptor weak partial agonistic activity showing the antidepressant-like effect. The 3-methoxyphenyl group and the phenethyl group of compound 1, which has weak SERT binding activity, but potent 5-HT1A binding activity, were optimized, leading to compound 35 with potent and balanced dual SERT and 5-HT1A binding activity, but also potent CYP2D6 inhibitory activity. Replacement of the methoxy group in the left part of compound 35 with a larger alkoxy group, such as ethoxy, isopropoxy or methoxy-ethoxy group ameliorated CYP2D6 inhibition, giving SMP-304 as a candidate. SMP-304 with serotonin uptake inhibitory activity and 5-HT1A weak partial agonistic activity, which could work as a 5-HT1A antagonist, displayed faster onset of antidepressant-like effect than a representative SSRI paroxetine in an animal model. 相似文献
999.
Alpha/beta‐hydrolases: A unique structural motif coordinates catalytic acid residue in 40 protein fold families
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Polytimi S. Dimitriou Alexander Denesyuk Seiji Takahashi Satoshi Yamashita Mark S. Johnson Toru Nakayama Konstantin Denessiouk 《Proteins》2017,85(10):1845-1855
The alpha/beta‐hydrolases are a family of acid‐base‐nucleophile catalytic triad enzymes with a common fold, but using a wide variety of substrates, having different pH optima, catalyzing unique catalytic reactions and often showing improved chemical and thermo stability. The ABH enzymes are prime targets for protein engineering. Here, we have classified active sites from 51 representative members of 40 structural ABH fold families into eight distinct conserved geometries. We demonstrate the occurrence of a common structural motif, the catalytic acid zone, at the catalytic triad acid turn. We show that binding of an external ligand does not change the structure of the catalytic acid zone and both the ligand‐free and ligand‐bound forms of the protein belong to the same catalytic acid zone subgroup. We also show that the catalytic acid zone coordinates the position of the catalytic histidine loop directly above its plane, and consequently, fixes the catalytic histidine in a proper position near the catalytic acid. Finally, we demonstrate that the catalytic acid zone plays a key role in multi‐subunit complex formation in ABH enzymes, and is involved in interactions with other proteins. As a result, we speculate that each of the catalytic triad residues has its own supporting structural scaffold, similar to the catalytic acid zone, described above, which together form the extended catalytic triad motif. Each scaffold coordinates the function of its respective catalytic residue, and can even compensate for the loss of protein function, if the catalytic amino acid is mutated. 相似文献
1000.
Sakai Kiyota Mochizuki Mai Yamada Miyuki Shinzawa Yuta Minezawa Miho Kimoto Saran Murata Shunsuke Kaneko Yuhei Ishihara Saaya Jindou Sadanari Kobayashi Tetsuo Kato Masashi Shimizu Motoyuki 《Applied microbiology and biotechnology》2017,101(8):3237-3245
Applied Microbiology and Biotechnology - A β-1,4-mannanase, termed AoMan134A, that belongs to the GH 134 family was identified in the filamentous fungus Aspergillus oryzae. Recombinant... 相似文献