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971.
Tsuyoshi Sato Takahiro Abe Norimichi Nakamoto Shoichiro Kokabu Yasuhisa Tomaru Michihiko Usui Tetsuya Yoda 《FEBS letters》2010,584(4):817-40
Recent studies have indicated that acetylcholine (ACh) plays a vital role in various tissues, while the role of ACh in bone metabolism remains unclear. Here we demonstrated that ACh induced cell proliferation and reduced alkaline phosphatase (ALP) activity via nicotinic (nAChRs) and muscarinic acetylcholine receptors (mAChRs) in osteoblasts. We detected mRNA expression of several nAChRs and mAChRs. Furthermore, we showed that cholinergic components were up-regulated and subunits/subtypes of acetylcholine receptors altered during osteoblast differentiation. To our knowledge, this is the first report demonstrating that osteoblasts express specific acetylcholine receptors and cholinergic components and that ACh plays a possible role in regulating the proliferation and differentiation of osteoblasts. 相似文献
972.
Kazuki Mochizuki Makiko Igawa-Tada Sachiko Takase Toshinao Goda 《Life sciences》2010,86(13-14):524-531
AimsWe examined whether decreasing jejunal sucrase/isomaltase (S/I) activity ratio by feeding rats a high fat/carbohydrate ratio diet is regulated by changing glycosylated chains on the S–I complex.Main methodsJejunal activities of sucrase, isomaltase and β-1,4-galactosyltransferase were examined in rats fed a high fat/carbohydrate or a low fat/carbohydrate ratio diet. The amount of galactose and mannose in the glycosylated chain on the S–I complex in rats fed both diets was determined using RCA120 and Con A lectins, respectively. The effects of reducing unsialylated galactose from the glycosylated chain on the S–I complex were assessed by determining sucrase activity in purified S–I complex treated with β-galactosidase.Key findings and significanceFeeding rats a high fat/carbohydrate ratio diet reduced jejunal S/I activity ratio in mucosal homogenates and purified fractions. The level of unsialylated galactose in glycosylated chains on the S–I complex was reduced by feeding rats a high fat/carbohydrate ratio diet. The form with reduced levels of unsialylated galactose had lower sucrase activity than that with more unsialylated galactose. The reduction of galactose on the S–I complex by β-galactosidase in vitro reduced sucrase activity. Feeding rats a high fat/carbohydrate ratio diet also reduced jejunal β-1,4-galactosyltransferase activity. Taken together, decreasing the S/I activity ratio by feeding rats a high fat/carbohydrate diet is associated with the reduction of unsialylated galactose on the glycosylated chain of the S–I complex. 相似文献
973.
Takuya Koseki Keiji Mochizuki Hiroe Kisara Akimasa Miyanaga Shinya Fushinobu Tetsuya Murayama Yoshihito Shiono 《Applied microbiology and biotechnology》2010,86(1):155-161
We engineered a chimeric enzyme (AwFaeA-CBM42) comprising of type-A feruloyl esterase from Aspergillus awamori (AwFaeA) and family 42 carbohydrate-binding module (AkCBM42) from glycoside hydrolase family 54 α-l-arabinofuranosidase of Aspergillus kawachii. The chimeric enzyme was successfully produced in Pichia pastoris and accumulated in the culture broth. The purified chimeric enzyme had an apparent relative molecular mass (M
r) of 53,000. The chimeric enzyme binds to arabinoxylan; this indicates that the AkCBM42 in AwFaeA-CBM42 binds to arabinofuranose
side chain moiety of arabinoxylan. The thermostability of the chimeric enzyme was greater than that of AwFaeA. No significant
difference of the specific activity toward methyl ferulate was observed between the AwFaeA and chimeric enzyme, but the release
of ferulic acid from insoluble arabinoxylan by the chimeric enzyme was approximately 4-fold higher than that achieved by AwFaeA
alone. In addition, the chimeric enzyme and xylanase acted synergistically for the degradation of arabinoxylan. In conclusion,
the findings of our study demonstrated that the components of the AwFaeA-CBM42 chimeric enzyme act synergistically to bring
about the degradation of complex substrates and that the family 42 carbohydrate-binding module has potential for application
in the degradation of polysaccharides. 相似文献
974.
Sun Mee Hong Jun Yamashita Hitoshi Mitsunobu Keiro Uchino Isao Kobayashi Hideki Sezutsu Toshiki Tamura Hideki Nakajima Yoshitaka Miyagawa Jae Man Lee Hiroaki Mon Yoshihiko Miyata Yutaka Kawaguchi Takahiro Kusakabe 《Applied microbiology and biotechnology》2010,87(6):2147-2156
Baculovirus expression systems (BES) are widely used for recombinant protein production in lepidopteran cells or larvae. However, even in BES, the insolubility of recombinant proteins sometimes makes their expression difficult. In this study, to improve the solubility and yield of foreign proteins, we constructed transgenic silkworms using silkworm heat-shock proteins, Hsp70 and Hsp40, or Hsc70 and Hsp90 co-chaperone Hop. In these transgenic silkworms, the expression levels of the transgenes were under the control of a UAS·hsp mini-promoter driven by a Gal4NFkBp65 activator. When the transgenic silkworm with HSP70 and 40 (TGS-HSP70/40) was infected with BmNPV carrying mC3d and Gal4NFkBp65 under the control of baculovirus polyhedrin or p10 promoters, respectively, the soluble fraction of the His- or His·GST-tagged mC3d increased significantly. Similarly, the transgenic silkworm with HSC70 and HOP (TGS-HOP7) was effective for the expression of a steroid hormone receptor, USP2. In conclusion, the His-tagged baculovirus expression system featuring the chaperone effect TGS-HSP70/40 and TGS-HOP7 silkworms is effective for increasing the yields of soluble and functional foreign gene products. 相似文献
975.
Tomoharu Tsukada Mizuki Takahashi Toshiyasu Takemoto Osamu Kanno Takahiro Yamane Sayako Kawamura Takahide Nishi 《Bioorganic & medicinal chemistry letters》2010,20(3):1004-1007
With the goal of improving metabolic stability and further enhancing FBPase inhibitory activity, a series of tricyclic 8H-indeno[1,2-d][1,3]thiazoles was designed and synthesized with the aid of structure-based drug design. Extensive SAR studies led to the discovery of 19a with an IC50 value of 1 nM against human FBPase. X-ray crystallographic studies revealed that high affinity of 19a was due to the hydrophobic interaction arising from better shape complementarity and to the hydrogen bonding network involving the side chain on the tricyclic scaffold. 相似文献
976.
Tomoharu Tsukada Osamu Kanno Takahiro Yamane Jun Tanaka Taishi Yoshida Akira Okuno Takeshi Shiiki Mizuki Takahashi Takahide Nishi 《Bioorganic & medicinal chemistry》2010,18(14):5346-5351
With the aim of exploring the effect of tricyclic-based FBPase inhibitors in cells and in vivo, a series of prodrugs of tricyclic phosphonates was designed and synthesized. Introducing prodrug moieties into tricyclic-based phosphonates led to the discovery of prodrug 15c, which strongly inhibited glucose production in monkey hepatocytes. Furthermore, prodrug 15c lowered blood glucose levels in fasted cynomolgus monkeys. 相似文献
977.
Taniguchi Y Nitta A Park SM Kohara A Uzu T Sasaki S 《Bioorganic & medicinal chemistry》2010,18(24):8614-8617
Potent peroxidase-like activity of the β-ketoenamine (1)-dicopper (II) complex (2) for the chemiluminescence (CL) of luminol either in the presence or absence of H(2)O(2) has been previously demonstrated by our group. In this study, the β-ketoenamine (1) as the ligand unit for copper(II) was incorporated into the oligonucleotide (ODN) probes. It has been shown that the catalytic activity of the ODN probes conjugating the ligand-Cu(II) complex is activated by hybridization with the target DNA with the complementary sequence. Thus, this study has successfully demonstrated the basic concept for the sensitive detection of nucleic acids by CL based on the template-inductive activation of the catalytic unit for CL. 相似文献
978.
Taiyo Toriba Takuya Suzaki Takahiro Yamaguchi Yoshihiro Ohmori Hirokazu Tsukaya Hiro-Yuki Hirano 《The Plant cell》2010,22(5):1452-1462
Establishment of adaxial-abaxial polarity is essential for lateral organ development. The mechanisms underlying the polarity establishment in the stamen remain unclear, whereas those in the leaf are well understood. Here, we investigated a rod-like lemma (rol) mutant of rice (Oryza sativa), in which the development of the stamen and lemma is severely compromised. We found that the rod-like structure of the lemma and disturbed anther patterning resulted from defects in the regulation of adaxial-abaxial polarity. Gene isolation indicated that the rol phenotype was caused by a weak mutation in SHOOTLESS2 (SHL2), which encodes an RNA-dependent RNA polymerase and functions in trans-acting small interfering RNA (ta-siRNA) production. Thus, ta-siRNA likely plays an important role in regulating the adaxial-abaxial polarity of floral organs in rice. Furthermore, we found that the spatial expression patterns of marker genes for adaxial-abaxial polarity are rearranged during anther development in the wild type. After this rearrangement, a newly formed polarity is likely to be established in a new developmental unit, the theca primordium. This idea is supported by observations of abnormal stamen development in the shl2-rol mutant. By contrast, the stamen filament is likely formed by abaxialization. Thus, a unique regulatory mechanism may be involved in regulating adaxial-abaxial polarity in stamen development. 相似文献
979.
Taiko Oda Jinzhong Xu Kazuyo Ukai Takahiro Nakazawa Michio Namikoshi 《Mycoscience》2010,51(4):317-320
Roridin E is a well-known macrocyclic trichothecene mycotoxin possessing potent antiproliferative activity against cancer
cell lines. 12′-Hydroxyroridin E was isolated from a marine-derived fungus, Myrothecium roridum 98F42. The cytotoxicities of these two compounds were tested against human monocytic THP-1, human promyelocytic leukemia
HL-60, and Chinese hamster V79 cells, and roridin E exhibited more than 1000-fold stronger cytotoxicity than its 12′-OH derivative;
therefore, it was suggested that the 12′-position is closely involved in the cytotoxicity of these compounds. 相似文献