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71.
Kentaro Uchiyama Tokuko Ujino-Ihara Saneyoshi Ueno Yuriko Taguchi Norihiro Futamura Kenji Shinohara Yoshihiko Tsumura 《Tree Genetics & Genomes》2012,8(6):1213-1222
In order to develop a large set of single-nucleotide polymorphisms (SNPs) in Cryptomeria japonica, for a wide range of applications, we adopted a systematic EST (expressed sequence tags) re-sequencing approach. We examined a group of four genotypes comprising parents of a mapping population as well as representatives of two main lines from natural populations. We sequenced 5,170 gene fragments, representing analysis of over 1.3?Mb of DNA sequences in C. japonica. This analysis leads to the discovery of 13,413 SNPs in 3,744 amplicons, with an average of one SNP for every 101.0?bp (one SNP for every 78.3?bp in introns and for every 106.7?bp in exon regions). Nucleotide diversity in C. japonica (???=?0.0045) was found to be similar to values recorded in highly polymorphic forest tree species such as pine. We also validated the use of the SNPs as molecular markers for genetic diversity studies using the high throughput SNP genotyping platform GoldenGate. From 1,536 candidate SNP sites tested, 1,164 (75.8?%) were confirmed to be polymorphic. We anticipate that the genome-wide SNP markers reported here will be useful for evaluating the species?? range-wide genetic structure and in marker-assisted selection used as part of the C. japonica tree improvement program. 相似文献
72.
Yamaguchi T Watanabe S Matsumura Y Tokuoka Y Yokoyama A 《Bioorganic & medicinal chemistry》2012,20(9):3058-3064
Vanadium complexes with quinoline ligands (1b-g) and pyridinone ligands (2b-d) were synthesized, and the effect of the length and shape of alkyl chains on the antiproliferative activity toward U937 cells was studied. For the synthesis of the vanadium complexes, quinoline and pyridinone ligands were prepared and then treated with VOSO(4) or VO(acac)(2). The vanadyl(IV) complexes were characterized by IR, ESR, and UV-vis spectroscopy and elemental analyses. The antiproliferative activity of 1a-g toward U937 cells showed little dependence on the length and shape of the alkyl chain. In contrast, a good correlation was found between the IC(50) values and partition coefficients (logP) values of 2a-c. Among them, 2c showed the highest inhibitory activity, and its IC(50) value was smaller than that of cisplatin. The apoptosis-inducing ability of 2b and 2c was supported by annexin V-propidium iodide staining experiments and agarose gel electrophoresis analysis. Inhibitors of caspase-3, -8, and -9 did not affect the antiproliferative activity of 2c, indicating that the apoptosis induced by 2c was via a caspase-independent pathway. 相似文献
73.
Shibata Y He LH Toda Y Kataoka Y Fujisawa N Miyazaki T Swain MV 《Journal of biomechanics》2008,41(16):3414-3418
The biomechanical stability of osseointegrated implants is of particular importance, especially the stability which is achieved from structural manipulation at the interface between the implant surface and the bone tissues. Nanoscale β-tricalcium phosphate-immobilized titanium was prepared by discharge into a physiological buffered saline solution. Compared with hydroxyapatite, it has been shown to be effective in generating a bone-like chemical structure on the surface by cooperative interaction between osteoblastic cells and the β-tricalcium phosphate. The present study, after cell cultivation, investigates the nanostructures and biomechanical property differences of a mineralized layer formed on two samples of nano-calcium phosphate-immobilized titanium. A scanning probe microscope study revealed that the mineralized tissue formed on the β-tricalcium phosphate samples after 1 week of cell culture showed significantly higher roughness, compared with hydroxyapatite samples. Nanoindentation micromechanical evaluation of the in vitro generated multilayered structures exhibited thicker bone-like mineralized layers on the β-tricalcium phosphate samples. A successful modification of titanium implants through the cooperative interaction between osteoblastic cells and nano β-tricalcium phosphate is anticipated. 相似文献
74.
Tomoaki Hishida Eric Vazquez-Ferrer Yuriko Hishida-Nozaki Ignacio Sancho-Martinez Yuta Takahashi Fumiyuki Hatanaka Jun Wu Alejandro Ocampo Pradeep Reddy Min-Zu Wu Laurie Gerken Reuben J. Shaw Concepcion Rodriguez Esteban Christopher Benner Hiroshi Nakagawa Pedro Guillen Garcia Estrella Nu ez Delicado Antoni Castells Josep M. Campistol Guang-Hui Liu Juan Carlos Izpisua Belmonte 《蛋白质与细胞》2019,10(7):485
Identification of the precise molecular pathways involved in oncogene-induced transformation may help us gain a better understanding of tumor initiation and promotion. Here, we demonstrate that SOX2+ foregut epithelial cells are prone to oncogenic transformation upon mutagenic insults, such as KrasG12D and p53 deletion. GFP-based lineage-tracing experiments indicate that SOX2+ cells are the cells-of-origin of esophagus and stomach hyperplasia. Our observations indicate distinct roles for oncogenic KRAS mutation and P53 deletion. p53 homozygous deletion is required for the acquisition of an invasive potential, and KrasG12D expression, but not p53 deletion, suffices for tumor formation. Global gene expression analysis reveals secreting factors upregulated in the hyperplasia induced by oncogenic KRAS and highlights a crucial role for the CXCR2 pathway in driving hyperplasia. Collectively, the array of genetic models presented here demonstrate that stratified epithelial cells are susceptible to oncogenic insults, which may lead to a better understanding of tumor initiation and aid in the design of new cancer therapeutics. 相似文献
75.
Yusaku Hioki Kyoko Ogasahara Soo Jae Lee Jichun Ma Masami Ishida Yuriko Yamagata Yoshiki Matsuura Motonori Ota Mitsunori Ikeguchi Seiki Kuramitsu Katsuhide Yutani 《European journal of biochemistry》2004,271(13):2624-2635
The structure of the tryptophan synthase beta2 subunit (Pfbeta2) from the hyperthermophile, Pyrococcus furiosus, was determined by X-ray crystallographic analysis at 2.2 A resolution, and its stability was examined by DSC. This is the first report of the X-ray structure of the tryptophan synthase beta2 subunit alone, although the structure of the tryptophan synthase alpha2beta2 complex from Salmonella typhimurium has already been reported. The structure of Pfbeta2 was essentially similar to that of the beta2 subunit (Stbeta2) in the alpha2beta2 complex from S. typhimurium. The sequence alignment with secondary structures of Pfbeta and Stbeta in monomeric form showed that six residues in the N-terminal region and three residues in the C-terminal region were deleted in Pfbeta, and one residue at Pro366 of Stbeta and at Ile63 of Pfbeta was inserted. The denaturation temperature of Pfbeta2 was higher by 35 degrees C than the reported values from mesophiles at approximately pH 8. On the basis of structural information on both proteins, the analyses of the contributions of each stabilization factor indicate that: (a) the higher stability of Pfbeta2 is not caused by either a hydrophobic interaction or an increase in ion pairs; (b) the number of hydrogen bonds involved in the main chains of Pfbeta is greater by about 10% than that of Stbeta, indicating that the secondary structures of Pfbeta are more stabilized than those of Stbeta and (c) the sequence of Pfbeta seems to be better fitted to an ideally stable structure than that of Stbeta, as assessed from X-ray structure data. 相似文献
76.
Keiko Hayashi Yoshikatsu Fujita Taketo Ashizawa Fumihiko Suzuki Yoshiaki Nagamura Yuriko Hayano‐Saito 《The Plant journal : for cell and molecular biology》2016,85(1):46-56
The hypersensitive response (HR) of plants is one of the earliest responses to prevent pathogen invasion. A brown dot lesion on a leaf is visual evidence of the HR against the blast fungus Magnaporthe oryzae in rice, but tracking the browning process has been difficult. In this study, we induced the HR in rice cultivars harboring the blast resistance gene Pit by inoculation of an incompatible M. oryzae strain, which generated a unique resistance lesion with a brown ring (halo) around the brown fungal penetration site. Inoculation analysis using a plant harboring Pit but lacking an enzyme that catalyzes tryptamine to serotonin showed that high accumulation of the oxidized form of serotonin was the cause of the browning at the halo and penetration site. Our analysis of the halo browning process in the rice leaf revealed that abscisic acid enhanced biosynthesis of serotonin under light conditions, and serotonin changed to the oxidized form via hydrogen peroxide produced by light. The dramatic increase in serotonin, which has a high antioxidant activity, suppressed leaf damage outside the halo, blocked expansion of the browning area and attenuated inhibition of plant growth. These results suggest that serotonin helps to reduce biotic stress in the plant by acting as a scavenger of oxygen radicals to protect uninfected tissues from oxidative damage caused by the HR. The deposition of its oxide at the HR lesion is observed as lesion browning. 相似文献
77.
78.
Rong S Ikeda H Sato Y Hirohashi Y Takamura Y Sahara H Sato T Maeda A Ohguro H Sato N 《Cancer immunology, immunotherapy : CII》2002,51(5):282-290
Recoverin is a photoreceptor-specific calcium binding protein that is only expressed in the retina in normal tissues. Aberrant expression of recoverin, however, has been observed in several cancer tissues and may cause a very rare autoimmune disease, cancer-associated retinopathy (CAR). It has been suggested that CAR-positive cancer patients have a more favorable prognosis than CAR-negative cancer patients. To estimate the status of recoverin-specific T cells in such cancer patients, we generated an HLA-A24-recoverin peptide tetramer. By use of the tetramer, we could directly assess the frequency of CTL precursors (CTLp) of 20 HLA-A24(+) cancer patients with ten colon, six stomach and four breast cancers, and seven healthy individuals. Four cancer patients showed a CTLp frequency higher than 0.9%. Seven cancer patients including the former four patients and two healthy individuals showed specific anti-recoverin cytotoxic responses in an HLA-A24-restricted manner after in vitro stimulation with the recoverin peptide. Moreover, five cancer patients analyzed in an independent experiment using different peripheral blood mononuclear cells (PBMC) samples showed similar CTLp and cytotoxic T lymphocyte (CTL) frequencies and cytotoxic responses, suggesting that the CTLp frequency analyzed by the tetramer and the cytotoxic response may have a good correlation. Thus, we hypothesize that anti-recoverin CTLp may exist in some cancer patients, and that anti-recoverin CTL may be readily induced. 相似文献
79.
Etsuko Moritsuka Phourin Chhang Shuichiro Tagane Hironori Toyama Heng Sokh Tetsukazu Yahara Hidenori Tachida 《Tree Genetics & Genomes》2017,13(6):115
Dalbergia cochinchinensis Pierre ex Laness. (Fabaceae) is a commercially important tree in Southeast Asia. Although this species is under legal protections, illegal logging and disorderly developments have reduced its populations, and the conservation of this species is currently of much concern. In this study, we determined nucleotide sequences at six chloroplasts and ten nuclear loci in four populations of D. cochinchinensis in Cambodia, followed by population genetic analyses. The average silent nucleotide diversity over the nuclear loci, excluding one with an exceptionally high value, was 0.0057 in the entire population, and the mean F ST across the nuclear loci between each population pair was between 0.135 and 0.467. Thus, the nucleotide diversity in the studied populations was not low compared with that in other tree species, and the level of population differentiation was high. Neutrality test statistics indicated a recent reduction of population size and a subdivision of the population within this species. The divergence times and migration rates were estimated with a likelihood-based method assuming the isolation with migration model. Based on the results, the three populations split 68,000–138,000 years ago, possibly corresponding to the start of the last glacial period, and the level of gene flow among the populations was very low thereafter. Moreover, after the split, population sizes were reduced considerably. Notably, the nucleotide diversity in an insertion sequence in a noncoding region of nuclear C4H was much higher than the mean nucleotide diversity in silent sites across other nuclear genes, indicating that the region was affected by selection. 相似文献
80.
Ikeda H Hirano Y Ziegler TA Saigusa M 《Journal of experimental zoology. Part A, Comparative experimental biology》2006,305(6):459-471
Hatching of embryos in the estuarine crab Sesarma haematocheir is highly synchronized with nocturnal high tide and completes within 1 hr among all embryos incubated by the female. This highly synchronized hatching is induced by a "Hatching-Program Inducing Factor (HPIF)" released from the female. To further define the cues involved in synchronized hatching, experiments were designed to characterize this factor and to determine possible sites of release and temporal release patterns using strategies involving isolation of egg masses, perfusion, and ablation experiments on fully developed embryos that had not yet entered the hatching program. Embryo transplantations indicate that not only HPIF may be released from the branchial chamber, but that it is extraordinarily unstable, and loses activity within 15 min, which frustrates further attempts at characterization. Nevertheless, with regard to temporal release patterns, it was established that HPIF activity was detected during short periods over three consecutive nights prior to release of larvae. This activity did not explain the gated response of embryo release in this crab, which might correspond with circatidal larval release events in the field. 相似文献