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991.
Aciculosporium take (Ascomycota; Clavicipitaceae), causes the witches' broom disease in bamboo, particularly Phyllostachys bambusoides. Since it was observed that endogenous indole-3-acetic acid is reduced in the twigs of the diseased bamboo, the symptoms (bushy appearance) may be induced by reduction in auxin levels. Furthermore, two indolic compounds accumulated in diseased twigs, these being identified as N-p-coumaroylserotonin and N-feruloylserotonin by LC-MS, 1H NMR and 13C NMR spectroscopic analyses. N-p-Coumaroylserotonin possesses antifungal activity against A. take. 相似文献
992.
Possible involvement of leaf gibberellins in the clock-controlled expression of XSP30, a gene encoding a xylem sap lectin, in cucumber roots 下载免费PDF全文
Root-produced organic compounds in xylem sap, such as hormones and amino acids, are known to be important in plant development. Recently, biochemical approaches have revealed the identities of several xylem sap proteins, but the biological functions and the regulation of the production of these proteins are not fully understood. XYLEM SAP PROTEIN 30 kD (XSP30), which is specifically expressed in the roots of cucumber (Cucumis sativus), encodes a lectin and is hypothesized as affecting the development of above-ground organs. In this report, we demonstrate that XSP30 gene expression and the level of XSP30 protein fluctuate in a diurnal rhythm in cucumber roots. The rhythmic gene expression continues for at least two or three cycles, even under continuous light or dark conditions, demonstrating that the expression of this gene is controlled by a circadian clock. Removal of mature leaves or treatment of shoots with uniconazole-P, an inhibitor of gibberellic acid (GA) biosynthesis, dampens the amplitude of the rhythmic expression; the application of GA negates these effects. These results suggest that light signals perceived by above-ground organs, as well as GA that is produced, possibly, in mature leaves, are important for the rhythmic expression of XSP30 in roots. This is the first demonstration of the regulation of the expression of a clock-controlled gene by GA. 相似文献
993.
An arylbenzofuran, erypoegin F and four isoflavonoids, erypoegins G-J, together with six known compounds were isolated from the roots of Erythrina poeppigiana, and their structures were elucidated on the basis of spectroscopic evidence. Erypoegin F is a rare 2-arylbenzofuran possessing a formyl group from a natural source, and erypoegin I is the first naturally occurring isoflavonoid with a 2-oxo-3-methylbutyl group. 相似文献
994.
995.
Horisaki A Tanaka N Niikura S 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(6):1009-1013
We have tried an insect-pollination self-incompatibility (SI) test to strictly evaluate the level of SI as a model for the actual F(1) seed production field using radish as experimental material. Twelve inbred lines, homozygous for the S-alleles, were used in the artificial self-pollination and the insect-pollination SI test. There was a positive correlation ( r = 0.606) between the results by these two methods. Some lines showed a low level of SI in the insect-pollination test despite showing a high level of SI in the artificial self-pollination test. On the other hand, no lines showing a low level of SI in artificial self-pollination had a high level of SI in insect-pollination. These results show that the insect-pollination SI test can be considered to be a more reliable and stricter method than the artificial self-pollination test with respect to an evaluation of SI levels. We have raised and analyzed an F(2) population and F(3) lines derived from an F(1) cross between a line showing a high level of SI (R00-04) and one showing a low level. The rate of self-seed settings of the F(2) population showed a binomial distribution. There were 39 high-level SI plants to 15 low-level SI plants. This result and F(3) progeny tests suggested that the high level of SI which R00-04 showed is controlled by a dominant gene. 相似文献
996.
De La Fuente J Golsteyn Thomas EJ van den Bussche RA Hamilton RG Tanaka EE Druhan SE Kocan KM 《Applied and environmental microbiology》2003,69(8):5001-5005
Anaplasma marginale (Rickettsiales: Anaplasmataceae), a tick-borne pathogen of cattle, is endemic in tropical and subtropical regions of the world. Although serologic tests have identified American bison, Bison bison, as being infected with A. marginale, the present study was undertaken to confirm A. marginale infection and to characterize isolates obtained from naturally infected bison in the United States and Canada. Major surface protein (MSP1a and MSP4) sequences of bison isolates were characterized in comparison with New World cattle isolates. Blood from one U.S. bison was inoculated into a susceptible, splenectomized calf, which developed acute anaplasmosis, demonstrating infectivity of this A. marginale bison isolate for cattle. The results of this study showed that these A. marginale isolates obtained from bison were similar to ones from naturally infected cattle. 相似文献
997.
l-Lactic acid was produced from raw cassava starch, by simultaneous enzyme production, starch saccharification and fermentation in a circulating loop bioreactor with Aspergillus awamori and Lactococcus lactis spp. lactis immobilized in loofa sponge. A. awamori was immobilized directly in cylindrical loofa sponge while the L. lactis was immobilized in a loofa sponge alginate gel cube. In the loofa sponge alginate gel cube, the sponge serves as skeletal support for the gel with the cells. The alginate gel formed a hard outer layer covering the soft porous gel inside. By controlling the rate and frequency of broth circulation between the riser and downcomer columns, the riser could be maintained under aerobic condition while the downcomer was under anaerobic condition. Repeated fed-batch l-lactic acid production was performed for more than 400 h and the average lactic acid yield and productivity from raw cassava starch were 0.76 g lactic acid g–1 starch and 1.6 g lactic acid l–1 h–1, respectively. 相似文献
998.
999.
1000.
Arakaki N Nagao T Niki R Toyofuku A Tanaka H Kuramoto Y Emoto Y Shibata H Magota K Higuti T 《Molecular cancer research : MCR》2003,1(13):931-939
Extracellular ATP synthesis on human umbilical vein endothelial cells (HUVECs) was examined, and it was found that HUVECs possess high ATP synthesis activity on the cell surface. Extracellular ATP generation was detected within 5 s after addition of ADP and inorganic phosphate and reached a maximal level at 15 s. This type of ATP synthesis was almost completely inhibited by mitochondrial H(+)-ATP synthase inhibitors (e.g., efrapeptins, resveratrol, and piceatannol), which target the F(1) catalytic domain. Oligomycin and carbonyl cyanide m-chlorophenylhydrazone, but not potassium cyanide, also inhibited extracellular ATP synthesis on HUVECs, suggesting that cell surface ATP synthase employs the transmembrane electrochemical potential difference of protons to synthesize ATP as well as mitochondrial H(+)-ATP synthase. The F(1)-targeting H(+)-ATP synthase inhibitors markedly inhibited the proliferation of HUVECs, but intracellular ATP levels in HUVECs treated with these inhibitors were only slightly affected, as shown by comparison with the control cells. Interestingly, piceatannol inhibited only partially the activation of Syk (a nonreceptor tyrosine kinase), which has been shown to play a role in a number of endothelial cell functions, including cell growth and migration. These findings suggest that H(+)-ATP synthase-like molecules on the surface of HUVECs play an important role not only in extracellular ATP synthesis but also in the proliferation of HUVECs. The present results demonstrate that the use of small molecular H(+)-ATP synthase inhibitors targeting the F(1) catalytic domain may lead to significant advances in potential antiangiogenic cancer therapies. 相似文献