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81.
Hema Balakrishna Bhat Takuma Kishimoto Mitsuhiro Abe Asami Makino Takehiko Inaba Motohide Murate Naoshi Dohmae Atsushi Kurahashi Kozo Nishibori Fumihiro Fujimori Peter Greimel Reiko Ishitsuka Toshihide Kobayashi 《Journal of lipid research》2013,54(10):2933-2943
A mixture of sphingomyelin (SM) and cholesterol (Chol) exhibits a characteristic lipid raft domain of the cell membranes that provides a platform to which various signal molecules as well as virus and bacterial proteins are recruited. Several proteins capable of specifically binding either SM or Chol have been reported. However, proteins that selectively bind to SM/Chol mixtures are less well characterized. In our screening for proteins specifically binding to SM/Chol liposomes, we identified a novel ortholog of Pleurotus ostreatus, pleurotolysin (Ply)A, from the extract of edible mushroom Pleurotus eryngii, named PlyA2. Enhanced green fluorescent protein (EGFP)-conjugated PlyA2 bound to SM/Chol but not to phosphatidylcholine/Chol liposomes. Cell surface labeling of PlyA2-EGFP was abolished after sphingomyelinase as well as methyl-β-cyclodextrin treatment, removing SM and Chol, respectively, indicating that PlyA2-EGFP specifically binds cell surface SM/Chol rafts. Tryptophan to alanine point mutation of PlyA2 revealed the importance of C-terminal tryptophan residues for SM/Chol binding. Our results indicate that PlyA2-EGFP is a novel protein probe to label SM/Chol lipid domains both in cell and model membranes. 相似文献
82.
Yuki Kishimoto Norikatsu Saito Katsumi Kurita Kentaro Shimokado Naoki Maruyama Akihito Ishigami 《Biochemical and biophysical research communications》2013,430(2):579-584
Ascorbic acid (AA) is essential for collagen biosynthesis as a cofactor for prolyl and lysyl hydroxylase and as a stimulus for collagen gene expression. Many studies have evaluated the relationship between AA and collagen expression in short- and long-term effects on cells after a single administration of AA into the culture medium. However, no such study has monitored in detail the stability of AA in medium or the alterations of intracellular AA levels during a protracted interval. Therefore, we examined here intracellular AA levels and stability throughout its exposure to human skin fibroblasts in vitro. Moreover, we determined the effects on type 1 and type 4 collagen and sodium-dependent vitamin C transporter (SVCT) gene expression when medium containing 100 μM AA was replaced every 24 h for 5 days to avoid depletion of AA. Throughout this long-term culture, intracellular AA levels remained constant; the expression of type 1 and type 4 collagens and SVCT2 mRNA was enhanced, and type 1 procollagen synthesis increased. Thus, these results indicate that human skin fibroblasts exposed to AA over time had rising levels of type 1/type 4 collagens and SVCT2 mRNA expression and type 1 procollagen synthesis. 相似文献
83.
Keishi Shimokawa Yoshinori Ueda Zenzaburo Kasai 《Bioscience, biotechnology, and biochemistry》2013,77(11):2021-2024
ABSTRACTJapanese apricot, Prunus mume Sieb. et Zucc., biosynthesizes the l-phenylalanine-derived cyanogenic glucosides prunasin and amygdalin. Prunasin has biological properties such as anti-inflammation, but plant extraction and chemical synthesis are impractical. In this study, we identified and characterized UGT85A47 from Japanese apricot. Further, UGT85A47 was utilized for prunasin microbial production. Full-length cDNA encoding UGT85A47 was isolated from Japanese apricot after 5?- and 3?-RACE. Recombinant UGT85A47 stoichiometrically catalyzed UDP-glucose consumption and synthesis of prunasin and UDP from mandelonitrile. Escherichia coli C41(DE3) cells expressing UGT85A47 produced prunasin (0.64 g/L) from racemic mandelonitrile and glucose. In addition, co-expression of genes encoding UDP-glucose biosynthetic enzymes (phosphoglucomutase and UTP-glucose 1-phosphate uridiltransferase) and polyphosphate kinase clearly improved prunasin production up to 2.3 g/L. These results showed that our whole-cell biocatalytic system is significantly more efficient than the existing prunasin production systems, such as chemical synthesis. 相似文献
84.
To search precursors of ethylene in banana fruits, ethylene formation from acetate-2-14C and fumarate-2,3-14C by banana slices was studied. Ethylene-14C formation from acetate-2-l4C was reduced by the addition of malonate or β-hydroxypropionate, and it was enhanced in a sealed chamber in comparison with the case in an aeration chamber. No label of fumarate-2,3-14C was incorporated into ethylene.From these facts it was suggested that acetate-2-14C was incorporated into ethylene via malonate and β-hydroxypropionate. Participation of fumarate in ethylene biosynthesis of banana fruits was ruled out. β-Hydroxypropionate was postulated as an effective precursor of ethylene formation from acetate-2-l4C. 相似文献
85.
Mechanism of Developmental Effects in Rats Caused by an N‐Phenylimide Herbicide: Transient Fetal Anemia and Sequelae during Mid‐to‐Late Gestation 下载免费PDF全文
86.
Naoko Minatani Mina Waraya Keishi Yamashita Mariko Kikuchi Hideki Ushiku Ken Kojo Akira Ema Hiroshi Nishimiya Yoshimasa Kosaka Hiroshi Katoh Norihiko Sengoku Hirokazu Tanino David Sidransky Masahiko Watanabe 《PloS one》2016,11(1)
Using pharmacological unmasking microarray, we identified promoter DNA methylation of cysteine dioxygenase 1 (CDO1) gene in human cancer. In this study, we assessed the clinicopathological significance of CDO1 methylation in primary breast cancer (BC) with no prior chemotherapy. The CDO1 DNA methylation was quantified by TaqMan methylation specific PCR (Q-MSP) in 7 BC cell lines and 172 primary BC patients with no prior chemotherapy. Promoter DNA of the CDO1 gene was hypermethylated in 6 BC cell lines except SK-BR3, and CDO1 gene expression was all silenced at mRNA level in the 7 BC cell lines. Quantification of CDO1 methylation was developed using Q-MSP, and assessed in primary BC. Among the clinicopathologic factors, CDO1 methylation level was not statistically significantly associated with any prognostic factors. The log-rank plot analysis elucidated that the higher methylation the tumors harbored, the poorer prognosis the patients exhibited. Using the median value of 58.0 as a cut-off one, disease specific survival in BC patients with CDO1 hypermethylation showed significantly poorer prognosis than those with hypomethylation (p = 0.004). Multivariate Cox proportional hazards model identified that CDO1 hypermethylation was prognostic factor as well as Ki-67 and hormone receptor status. The most intriguingly, CDO1 hypermethylation was of robust prognostic relevance in triple negative BC (p = 0.007). Promoter DNA methylation of CDO1 gene was robust prognostic indicator in primary BC patients with no prior chemotherapy. Prognostic relevance of the CDO1 promoter DNA methylation is worthy of being paid attention in triple negative BC cancer. 相似文献
87.
Tomohiro Iguchi Sho Nambara Takaaki Masuda Hisateru Komatsu Masami Ueda Shinya Kidogami Yushi Ogawa Qingjiang Hu Kuniaki Sato Tomoko Saito Hidenari Hirata Shotaro Sakimura Ryutaro Uchi Naoki Hayashi Shuhei Ito Hidetoshi Eguchi Keishi Sugimachi Yoshihiko Maehara Koshi Mimori 《PloS one》2016,11(11)
miR-146a plays important roles in cancer as it directly targets NUMB, an inhibitor of Notch signaling. miR-146a is reportedly regulated by a G>C polymorphism (SNP; rs2910164). This polymorphism affects various cancers, including colorectal cancer (CRC). However, the clinical significance of miR-146a polymorphism in CRC remains unclear. A total of 59 patients with CRC were divided into 2 groups: a CC/CG genotype (n = 32) and a GG genotype (n = 27), based on the miR-146a polymorphism. cDNA microarray analysis was performed using 59 clinical samples. Significantly enriched gene sets in each genotype were extracted using GSEA. We also investigated the association between miR-146a polymorphism and miR-146a, NUMB expression or migratory response in CRC cell lines. The CC/CG genotype was associated with significantly more synchronous liver metastasis (p = 0.007). A heat map of the two genotypes showed that the expression profiles were clearly stratified. GSEA indicated that Notch signaling and JAK/STAT3 signaling were significantly associated with the CC/CG genotype (p = 0.004 and p = 0.023, respectively). CRC cell lines with the pre-miR-146a/C revealed significantly higher miR-146a expression (p = 0.034) and higher NUMB expression and chemotactic activity. In CRC, miR-146a polymorphism is involved in liver metastasis. Identification of this polymorphism could be useful to identify patients with a high risk of liver metastasis in CRC. 相似文献
88.
89.
Koki Kuramochi Kohsuke Uchimura Atsushi Kurata Tohru Kobayashi Yuu Hirose Takeshi Miura Noriaki Kishimoto Ron Usami Koki Horikoshi 《Extremophiles : life under extreme conditions》2016,20(4):471-478
An endo β-1,4-xylanase (XynE15) from a culture broth of a deep subseafloor microorganism, Microcella alkaliphila JAM-AC0309, was purified to homogeneity. The molecular mass of XynE15 was approximately 150 kDa as judged by SDS-PAGE. The optimal pH and temperature for hydrolysis of xylan were pH 8 and 65 °C. The enzyme was stable to incubation for 30 min at up to 75 °C, and the half-life at 50 °C was 48 h. XynE15 hydrolyzed arabinoxylan, oat spelt xylan, and birchwood xylan well, but not avicel, carboxymethylcellulose, or arabinan. Xylooligosaccharides were hydrolyzed to mainly xylobiose from higher than xylotetraose. The genome sequencing analysis of strain JAM-AC03039 revealed that XynE15 was composed of 1,319 amino acids with one catalytic domain and three carbohydrate-binding domains belonging to glycoside hydrolase (GH) family 10 and carbohydrate-binding module (CBM) family 4, respectively. 相似文献
90.
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