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241.
Fumie Shimizu Masashi Shiiba Katsunori Ogawara Ryota Kimura Yasuyuki Minakawa Takao Baba Satoshi Yokota Dai Nakashima Morihiro Higo Atsushi Kasamatsu Yosuke Sakamoto Hideki Tanzawa Katsuhiro Uzawa 《PloS one》2013,8(12)
Background
LIM and SH3 protein 1 (LASP-1) is a specific focal adhesion protein involved in several malignant tumors. However, its role in oral squamous cell carcinoma (OSCC) is unknown. The aim of this study was to characterize the role and molecular status/mechanism of LASP-1 in OSCC.Methods
We evaluated LASP-1 mRNA and protein expressions in OSCC-derived cell lines and primary OSCCs. Using an shRNA system, we analyzed the effect of LASP-1 on the biology and function of the OSCC cell lines, HSC-3 and Ca9-22. The cells also were subcutaneously injected to evaluate tumor growth in vivo. Data were analyzed by the Fisher’s exact test or the Mann-Whitney U test. Bonferroni correction was used for multiple testing.Results
Significant up-regulation of LASP-1 was detected in OSCC-derived cell lines (n = 7, P<0.007) and primary OSCCs (n = 50, P<0.001) compared to normal controls. LASP-1 knockdown cells significantly inhibited cellular proliferation compared with shMock-transfected cells (P<0.025) by arresting cell-cycle progression at the G2 phase. We observed dramatic reduction in the growth of shLASP-1 OSCC xenografts compared with shMock xenografts in vivo.Conclusion
Our results suggested that overexpression of LASP-1 is linked closely to oral tumourigenicity and further provide novel evidence that LASP-1 plays an essential role in tumor cellular growth by mediating G2/M transition. 相似文献242.
Background and aims
The teosinte Zea nicaraguensis, which is adapted to frequently flooded lowlands, is considered a valuable germplasm resource for the development of flooding-tolerant maize. This species can form constitutive root aerenchyma under well-drained conditions. The objectives of this study were to screen Z. nicaraguensis accessions for the capacity to form constitutive aerenchyma, to obtain progeny with differing degrees of aerenchyma formation, and to compare the flooding tolerance of these progeny.Methods
We evaluated constitutive aerenchyma formation in the root cortex of seedlings of eight accessions and several segregating populations of Z. nicaraguensis. We also evaluated flooding tolerance in lines selected for high or low degrees of constitutive aerenchyma formation.Results
Seedlings of the eight accessions showed an extremely wide and continuous range of variation in aerenchyma formation. By phenotypic selection within two accessions, we obtained lines with either high or low degrees of constitutive aerenchyma formation. The lines selected for a higher degree of formation showed relatively high flooding tolerance evaluated by shoot dry weight ratio (flooded:control) than those with a lower degree of formation.Conclusions
A greater capacity to form constitutive aerenchyma can enhance flooding tolerance. 相似文献243.
cDNAs of the ecdysone receptor and the retinoid X receptor were cloned from the Japanese scorpion Liocheles australasiae, and the amino acid sequences were deduced. The full-length cDNA sequences of the L. australasiae ecdysone receptor and the L. australasiae retinoid X receptor were 2881 and 1977 bp in length, respectively, and the open reading frames encoded proteins of 560 and 414 amino acids. The amino acid sequence of the L. australasiae ecdysone receptor was similar to that of the ecdysone receptor-A of the soft tick, Ornithodoros moubata (68%) and to that of the ecdysone receptor-A1 of the lone star tick, Amblyomma americanum (66%), but showed lower similarity to the ecdysone receptors of Orthoptera and Coleoptera (53-57%). The primary sequence of the ligand-binding region of the L. australasiae ecdysone receptor was highly homologous to that of ticks (85-86%). The amino acid sequence of the L. australasiae retinoid X receptor was also homologous to the amino acid sequence of ultraspiracles of ticks (63%) and insects belonging to the orders Orthoptera and Coleoptera (60-64%). The identity of both the L. australasiae ecdysone receptor and the L. australasiae retinoid X receptor to their lepidopteran and dipteran orthologs was less than 50%. The cDNAs of both the L. australasiae ecdysone receptor (L. australasiae ecdysone receptor-A) and the L. australasiae retinoid X receptor were successfully translated in vitro using a rabbit reticulocyte lysate system. An ecdysone analog, ponasterone A, bound to L. australasiae ecdysone receptor-A (K(D) = 4.2 nM), but not to L. australasiae retinoid X receptor. The L. australasiae retinoid X receptor did not enhance the binding of ponasterone A to L. australasiae ecdysone receptor-A, although L. australasiae retinoid X receptor was necessary for the binding of L. australasiae ecdysone receptor-A to ecdysone response elements. 相似文献
244.
Mizushima F Minoura K Tomoo K Sumida M Taniguchi T Ishida T 《Journal of biochemistry》2007,142(1):49-54
The heparin-induced self-aggregation behaviours of four repeat peptides (R1-R4) in an acidic solution (pH = 4.5) were investigated by fluorescence and circular dichroism (CD) measurements and compared with those in a neutral solution (pH = 7.5). In contrast with the self-aggregation-resistive behaviours of the R1 and R4 repeat peptides in the neutral solution, the R4 peptide formed a filament similarly to the R2 and R3 peptides in the acidic solution, whereas the R1 peptide still showed resistive behaviour for filament formation. This is the first report on the markedly different self-aggregation behaviours of the first and fourth repeat peptides on tau microtubule-binding domain. 相似文献
245.
Simple micropatterning method for enhancing fusion efficiency and responsiveness to electrical stimulation of C2C12 myotubes 下载免费PDF全文
Yuzo Takayama Akira Wagatsuma Takayuki Hoshino Kunihiko Mabuchi 《Biotechnology progress》2015,31(1):220-225
Cultured myotubes induced in vitro from myoblast cell lines have been widely used to investigate muscle functional properties and disease‐related biological phenotypes. Until now, several cell patterning techniques have been applied to regulate in vitro myotube structures. However, these previous studies required specific geometry patterns or soft materials for inducing efficient myotube formation. Thus, more simple and easy handling method will be promising. In this study, we aimed to provide a method to form C2C12 myotubes with regulated sizes and orientations in simple line patterns. We used a poly(dimethylsiloxane) (PDMS) stamp and a 2‐methacryloyloxyethyl phosphorylcholine (MPC) polymer solution to fabricate line patterns for myotube formation onto a culture dish. We confirmed that C2C12 myotubes of well‐defined size and orientation were reproducibly formed. In particular, myotubes formed in the micropatterned lines showed the increased fusion efficiency. Then, functional dynamics in the micropatterned myotubes were detected and analyzed using a calcium imaging method. We confirmed micropatterning in line patterns enhanced the responsiveness of myotubes to external electrical stimulations. These results indicate that micropatterning myoblasts with the MPC polymer is a simple and effective method to form functional myotube networks. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 31:220–225, 2015 相似文献
246.
Construction of a Library of Human Glycosyltransferases Immobilized in the Cell Wall of Saccharomyces cerevisiae 下载免费PDF全文
Yoh-ichi Shimma Fumie Saito Fumi Oosawa Yoshifumi Jigami 《Applied microbiology》2006,72(11):7003-7012
Fifty-one human glycosyltransferases were expressed in Saccharomyces cerevisiae as immobilized enzymes and were assayed for enzymatic activities. The stem and catalytic regions of sialyl-, fucosyl-, galactosyl-, N-acetylgalactosaminyl-, and N-acetylglucosaminyltransferases were fused with yeast cell wall Pir proteins, which anchor glycosyltransferases at the yeast cell wall glucan. More than 75% of expressed recombinant glycosyltransferases retained their enzymatic activities in the yeast cell wall fraction and will be used as a human glycosyltransferase library. In increasing the enzymatic activities of immobilized glycosyltransferases, several approaches were found to be effective. Additional expression of yeast protein disulfide isomerase increased the expression levels and activities of polypeptide N-acetylgalactosaminyltransferases and other glycosyltransferases. PIR3 and/or PIR4 was more effective than PIR1 as a cell wall anchor when the Pir-glycosyltransferase fusions were expressed under the control of the constitutive glyceraldehyde-3-phosphate dehydrogenase promoter. Oligosaccharides such as Lewis x, Lewis y, and H antigen were successfully synthesized using this immobilized glycosyltransferase library, indicating that the Pir-fused glycosyltransferases are useful for the production of various human oligosaccharides. 相似文献
247.
Tomoyasu Ikeno Ryoji Minami Koji Wagatsuma Shinsuke Fujibayashi Tooru Nakao Katsuyuki Abo Satoshi Tsugawa Shigeru Taniguchi Yuhei Takasago 《Human genetics》1981,59(4):353-359
Summary A prenatal diagnosis of Hurler's syndrome was made in a pregnancy at risk in a family with two affected children. The fetus was diagnosed as having Hurler's syndrome on the basis of a deficiency of -L-iduronidase in the cultured amniotic cells. The glycosaminoglycans (GAG) content in the supernatant of the amniotic fluid was increased about 1.5 fold compared with that in the control, and increases of heparan sulfate and dermatan sulfate were observed on electrophoresis.The diagnosis could be confirmed by the deficiencies of -L-iduronidase in the liver and brain from the affected fetus. GAG content in the liver from the affected fetus was increased approximately 10 fold as compared with that in the control fetal liver, and most of the GAG were degraded. The GAG content was observed to be increased two fold in the brain, and dermatan sulfate, which was not detected in normal fetal brain, was identified. -galactosidase activities in the affected liver and brain were decreased to 30tt50% of the control, and an altered hexosaminidase A was also observed in the liver. 相似文献
248.
Keizo Waku Fumie Hayakawa Yasuo Nakazawa 《Archives of biochemistry and biophysics》1980,204(1):288-293
The effects of cadmium ions or cadmium-metallothionein on the activities of acyl-CoA:1acyl-sn-glycerol 3-phosphoric acid or 1-acyl-sn-glycero 3-phosphocholine acyltransferase of rat liver microsomes have been studied, in vitro. Cadmium ions were found to cause a noncompetitive type inhibition of these two acyltransferases. The Ki values were calculated, and found to be smallest (1.7 × 10?5m) for palmitoyl-CoA and greatest (1.0 × 10?4m) for linoleoyl-CoA, among the several fatty acyl-CoA's tested on the 1-acyl-sn-glycerol 3-phosphoric acid acyltransferases. With the 1-acyl-sn-glycero 3-phosphocholine acyltransferase, the Ki values were found to be smallest for the plamitoyl-CoA acyltransferase (3.8 × 10?5m) and largest for thearachidonoyl-CoA acyltransferase (1.1 × 10?4m). In contrast, mouse liver cadmium-metallothionein, including 4 mol of cadmium and 2 mol of zinc in one molecule of metallothionein, was not found to be inhibitory or rather stimulative on the above two acyltransferases at the same concentration of cadmium tested in the cadmium ion inhibitor experiments. The above results demonstrate that there is a strong and irreversible inhibition by cadmium ions on acyl-CoA acyltransferases, but that when cadmium acts on the enzyme in the form of a cadmium-metallothionein complex, the inhibition effect does not occur. These findings may reflect differing degrees of toxicity of these two types of cadmium compounds in mammalian tissues. 相似文献
249.
Koga T Sakamoto F Yamoto A Takumi K 《The Journal of General and Applied Microbiology》1999,45(4):155-161
The relationship of acid adaptation to the resistance of other environmental stresses was examined in Vibrio parahaemolyticus. Acid-adapted cells were found to have increased resistance to various stresses, including heat, crystal violet, bile, and deoxy cholic acid. However, heat-adapted cells showed no increased resistance against acid stress. Adaptation required protein synthesis, since treatment with chloramphenicol during adaptation to pH 5.3 prevented the development of acid resistance. Acid-adapted cells showed an increased amount of outer membrane protein with an apparent molecular weight of 27,000. These results show that acid-induced cross-protection involved changes in outer membrane protein composition and the known enhancement of intracellular pH homeostasis. 相似文献
250.