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11.
Lipid contents and compositions of the bleached Okinawan corals were analyzed for the first time. Bleached corals collected
at Sesoko Okinawa, Japan (26°38′N, 127°52′E), after the 1998 bleaching event showed decreased lipid content with a concomitant
decline of wax in the lipid composition. The reductionin the lipid content of corals showed diversity depending on their colony
morphology. On the whole, corals of massive morphology were relatively rich in lipid even after the bleaching event, and hence
lesser reduction in the lipid content compared with the cases for those of branching morphology. Furthermore, there was a
positive correlation between lipid content and zooxanthellae density in the bleached corals, suggesting again the importance
of symbiont for the supply of lipid to the host cells, and hence for the survival of the bleaching event. 相似文献
12.
ABSTRACT: Glucose has been implicated in functioning as a form of carbon translocated from symbiont zooxanthellae to the host coral cell. The present paper describes the lipid biosynthesis from [14 C]-glucose in the coral tissue. To study the incorporation of [14 C]-glucose into lipids, the branch tips of the coral Montipora digitata were incubated with [14 C]-glucose or another radiolabeled substrates. The lipid biosynthesis from [14 C]-glucose was dependent on light, and was decreased by dark conditions or by photosystem II inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Of the lipid classes, the light dependency was more pronounced with the biosynthesis of triacylglycerols (TG) and wax compared with phospholipids. Examination of [14 C]-label distribution in the glycerolipids suggested that [14 C]-glucose supplied mainly the fatty acid moiety of newly synthesized TG, while [14 C]-glucose provided evenly the fatty acid moiety and the glycerol skeleton of phospholipids. The comparison of [14 C]-labeling of lipid from host coral tissue and symbiont zooxanthellae suggested that [14 C]-glucose entered the coral cell and was processed in parallel in the zooxanthellae and host cells. Furthermore, the coral cells used various [14 C]-labeled sugars for lipid synthesis with similar lipid labeling profile as was the case for glucose. The current study thus supports the view that the low-molecular-weight compound, sugars and amino acids, once translocated from zooxanthellae to host cell were metabolized toward lipogenesis as well as glycerol. 相似文献
13.
Kyoko Takagi Akito Kaga Masao Ishimoto Makita Hajika Toshiro Matsunaga 《Breeding Science》2015,65(5):372-380
Radiocesium is an extremely harmful radionuclide because of its long half-life; it is important to reduce its transfer from contaminated soil into crops. Here we surveyed genetic variation for seed cesium (Cs) concentration in soybean mini-core collections representing large genetic diversity. The collections grown over 3 years in rotational paddy fields exhibited varying seed Cs concentrations with significant year-to-year correlations, although the phenotypic stability of Cs concentration was lower than that of the congeners potassium (K) and rubidium (Rb). Although Cs is supposedly accumulated in plants via the K transport system, there was no apparent relationship between Cs and K concentrations, whereas a clear positive correlation was observed between Cs and Rb concentrations. Cs and K concentrations in seed showed slightly positive and negative correlations, respectively, with days to flowering. We selected several high or low Cs accumulator candidates on the basis of the 3 years of seed concentration data. These two groups showed significantly different seed Cs concentrations in another field. The differences could not be explained by flowering time alone. These results suggest that genetic variation for seed Cs concentration is present in soybean germplasm and would be useful for breeding low Cs-accumulating varieties. 相似文献
14.
15.
Saito M Saito K Kunisaki N Kimura S 《Journal of agricultural and food chemistry》2002,50(24):7169-7174
We have investigated the inhibitory effects of polyphenols from natural products, such as green tea, bilberry, grape, ginkgo, and apple, on rainbow trout gelatinase activities. Gelatinases from the skin, muscle, and blood of rainbow trout contained serine proteinase, metalloproteinase, and other proteinase activities as measured by gelatin zymography. The polyphenols of green tea caused the strong inhibition of some gelatinase activities when compared with those of the other products. This inhibition was quite similar to that of metalloproteinase by ethylenediaminetetraacetic acid, suggesting that the effects of green tea polyphenols on proteinase activities are specific for metalloproteinases. The major catechins of green tea polyphenols were then separated and identified by reverse-phase chromatography to be (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin, (-)-epicatechin gallate, and (-)-epicatechin. The effects of these catechins on gelatinase activities were examined; the most potent inhibitor of metalloproteinase activities was found to be EGCG. These results have indicated that green tea polyphenols including EGCG are useful for regulating metalloproteinase activities of fish meat. 相似文献
16.
Trans-endocytosis of CD80 and CD86: a molecular basis for the cell-extrinsic function of CTLA-4 总被引:1,自引:0,他引:1
Qureshi OS Zheng Y Nakamura K Attridge K Manzotti C Schmidt EM Baker J Jeffery LE Kaur S Briggs Z Hou TZ Futter CE Anderson G Walker LS Sansom DM 《Science (New York, N.Y.)》2011,332(6029):600-603
Cytotoxic T lymphocyte antigen 4 (CTLA-4) is an essential negative regulator of T cell immune responses whose mechanism of action is the subject of debate. CTLA-4 shares two ligands (CD80 and CD86) with a stimulatory receptor, CD28. Here, we show that CTLA-4 can capture its ligands from opposing cells by a process of trans-endocytosis. After removal, these costimulatory ligands are degraded inside CTLA-4-expressing cells, resulting in impaired costimulation via CD28. Acquisition of CD86 from antigen-presenting cells is stimulated by T cell receptor engagement and observed in vitro and in vivo. These data reveal a mechanism of immune regulation in which CTLA-4 acts as an effector molecule to inhibit CD28 costimulation by the cell-extrinsic depletion of ligands, accounting for many of the known features of the CD28-CTLA-4 system. 相似文献
17.
Okada A Shishido T Nakano K Ito K Tamura K Fujiwara M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1441-1445
In order to evaluate the physiological roles of the testicular endothelin (Edn) signaling via Edn receptor subtype-A (Ednra) in mammals, the localization of Ednra was investigated by in situ hybridization and immunohistochemistry in the testis of rats, dogs, and monkeys. For in situ hybridization, a rat Ednra RNA probe which is highly homologous to the subcloned canine and monkey Ednra (88.7% and 87.9% identical, respectively) was used. Both Ednra mRNA and protein were detected in interstitial cells and cells in the basal compartment of the seminiferous tubules, mainly Sertoli cells, as well as spermatogonia and some early spermatocytes, but not spermatids. The localization pattern of Ednra was exhibited in a same manner among species, indicating that the physiological role of Edn signaling throughout Ednra was maintained in the mammalian testis. 相似文献
18.
Sakudo A Tsenkova R Tei K Morita H Ikuta K Onodera T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1375-1378
The risk of infections from zoonotic pathogens of tissues and/or tissue-derived products has been increasing. One preventive approach in reducing infection risk is tissue decontamination, where selection and screening of highly infectious tissues are strictly followed. Therefore, the development of reliable analytical methods for rapid tissue discrimination is essentially important. In the present study, a procedure has been developed for intact tissue discrimination on the basis of multivariate analysis of visible and near-infrared (Vis-NIR) spectra of certain tissues such as brain, liver, kidney and testis of mice without any pretreatment. Transmittance spectra in the 600- to 1000-nm regions were subjected to a principal component analysis (PCA), and leave-out cross-validation was employed to develop multivariate models for tissue discrimination. The plot of PCA scores against Vis-NIR spectra of brains, kidneys, livers and testes from 11 mice portrayed reliable tissue discrimination. This result suggests that Vis-NIR spectroscopy combined with chemometrics analysis may provide a potentially useful approach for rapid non-destructive discrimination of tissues. 相似文献
19.
Kyoko Sugawara Misako Himeno Takuya Keima Yugo Kitazawa Kensaku Maejima Kenro Oshima Shigetou Namba 《Journal of General Plant Pathology》2012,78(6):389-397
Phytoplasmas are plant pathogenic bacteria that infect more than 700 plant species. Because phytoplasma-resistant cultivars are not available for the vast majority of crops, the most common practice to prevent phytoplasma diseases is to remove infected plants. Therefore, developing a rapid, accurate diagnostic method to detect a phytoplasma infection is important. Here, we developed a phytoplasma detection assay based on loop-mediated isothermal amplification (LAMP) by targeting the groEL gene and 16S rDNA. We designed 19 primer sets for the LAMP assay and evaluated their amplification efficiency, sensitivity, and spectra to select the most suitable primer sets to detect Candidatus Phytoplasma asteris. As a result, DNA was efficiently amplified by one of the primer sets targeting the groEL gene, and LAMP assay sensitivity with this primer set was 10-fold higher than that of the polymerase chain reaction. Moreover, the groEL gene was successfully amplified from several strains of Ca. Phytoplasma asteris by this primer set, indicating that the groEL gene can be used as a LAMP assay target gene for a broad range of phytoplasma strains. Additionally, a simple DNA extraction method that omits the homogenizing and phenol extraction steps was combined with the LAMP assay to develop a simple, rapid, and convenient diagnostic method for detecting phytoplasma. 相似文献
20.
Sakagami N Umeki H Nishino O Uchiyama H Ichikawa K Takeshita K Kaneko E Akiyama K Kobayashi S Tamada H 《The Journal of reproduction and development》2012,58(1):140-146
The objective of this study was to examine whether high concentrations of epidermal growth factor (EGF) and/or insulin-like growth factor I (IGF-I) would have a beneficial effect on bovine embryo development in vitro and to obtain normal calves by using an ovum pick up method and embryo culture in a chemically defined medium. When compared with controls, EGF (100 or 200 ng/ml) or IGF-I (50 or 100 ng/ml) significantly increased the rate of embryos that developed into blastocysts during an 8-day culture after the in vitro fertilization of oocytes obtained from ovaries from a slaughterhouse. IGF-I induced a dose-dependent increase in cell number in both the inner cell mass and the trophectoderm, whereas EGF stimulated proliferation only in the inner cell mass. A combination of EGF (100 ng/ml) and IGF-I (50 ng/ml) produced an additive effect, and embryos developed into blastocysts at a comparatively high rate (27.9%) compared with controls (12.0%). A similar rate of development was achieved using a combination of EGF and IGF-I in the culture of embryos following ovum pick up by ultrasound-guided transvaginal follicular aspiration and in vitro fertilization, and 5 blastocysts that developed after the culture were transferred into uteri; two embryos implanted, and normal calves were born. These results suggest that the combined use of EGF and IGF-I makes bovine embryo culture in a chemically defined medium a practical and useful procedure for producing blastocysts, and its application to embryo culture following ovum pick up and in vitro fertilization could be useful for producing normal calves. 相似文献