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61.
Plants under herbivore attack emit mixtures of volatiles (herbivore-induced plant volatiles, HIPVs) that can attract predators of the herbivores. Although the composition of HIPVs should be critical for the attraction, most studies of transgenic plant-emitted volatiles have simply addressed the effect of trans-volatiles without embedding in other endogenous plant volatiles. We investigated the abilities of transgenic wishbone flower plants (Torenia hybrida and Torenia fournieri) infested with spider mites, emitting a trans-volatile ((E)-β-ocimene) in the presence or absence of endogenous volatiles (natural HIPVs and/or floral volatiles), to attract predatory mites (Phytoseiulus persimilis). In both olfactory- and glasshouse-based assays, P. persimilis females were attracted to natural HIPVs from infested wildtype (wt) plants of T. hybrida but not to those of T. fournieri. The trans-volatile enhanced the ability to attract P. persimilis only when added to an active HIPV blend from the infested transgenic T. hybrida plants, in comparison with the attraction by infested wt plants. Intriguingly, floral volatiles abolished the enhanced attractive ability of T. hybrida transformants, although floral volatiles themselves did not elicit any attraction or avoidance behavior. Predator responses to trans-volatiles were found to depend on various background volatiles (e.g. natural HIPVs and floral volatiles) endogenously emitted by the transgenic plants. 相似文献
62.
Eri Nishihara Etsuo Yokota Akira Tazaki Hidefumi Orii Maki Katsuhara Kensuke Kataoka Hisako Igarashi Yoshinori Moriyama Teruo Shimmen Seiji Sonobe 《Biology of the cell / under the auspices of the European Cell Biology Organization》2008,100(3):179-188
BACKGROUND INFORMATION: The results of water permeability measurements suggest the presence of an AQP (aquaporin) in the membrane of the CV (contractile vacuole) in Amoeba proteus [Nishihara, Shimmen and Sonobe (2004) Cell Struct. Funct. 29, 85-90]. RESULTS: In the present study, we cloned an AQP gene from A. proteus [ApAQP (A. proteus AQP)] that encodes a 295-amino-acid protein. The protein has six putative TMs (transmembrane domains) and two NPA (Asn-Pro-Ala) motifs, which are conserved among various AQPs and are thought to be involved in the formation of water channels that span the lipid bilayer. Using Xenopus oocytes, we have demonstrated that the ApAQP protein product can function as a water channel. Immunofluorescence microscopy with anti-ApAQP antibody revealed that ApAQP is detected on the CV membrane and on the vesicles around the CV. The presence of V-ATPase (vacuolar H+-ATPase) on the vesicle membrane around the CV was also detected. CONCLUSIONS: Our data on ApAQP allow us to provide the first informed explanation of the high water permeability of the CV membrane in amoeba. Moreover, the results suggest that vesicles possessing V-ATPase are involved in generating an osmotic gradient. Based on our findings, we propose a new hypothesis for the mechanism of CV function. 相似文献
63.
Hirota K Sakamaki J Ishida J Shimamoto Y Nishihara S Kodama N Ohta K Yamamoto M Tanimoto K Fukamizu A 《The Journal of biological chemistry》2008,283(47):32432-32441
64.
Nishihara E Yokota E Tazaki A Orii H Katsuhara M Kataoka K Igarashi H Moriyama Y Shimmen T Sonobe S 《Biology of the cell / under the auspices of the European Cell Biology Organization》2008,100(3):179-188
Background information. The results of water permeability measurements suggest the presence of an AQP (aquaporin) in the membrane of the CV (contractile vacuole) in Amoeba proteus [Nishihara, Shimmen and Sonobe ( 2004 ) Cell Struct. Funct. 29 , 85–90]. Results. In the present study, we cloned an AQP gene from A. proteus [ApAQP (A. proteus AQP)] that encodes a 295‐amino‐acid protein. The protein has six putative TMs (transmembrane domains) and two NPA (Asn‐Pro‐Ala) motifs, which are conserved among various AQPs and are thought to be involved in the formation of water channels that span the lipid bilayer. Using Xenopus oocytes, we have demonstrated that the ApAQP protein product can function as a water channel. Immunofluorescence microscopy with anti‐ApAQP antibody revealed that ApAQP is detected on the CV membrane and on the vesicles around the CV. The presence of V‐ATPase (vacuolar H+‐ATPase) on the vesicle membrane around the CV was also detected. Conclusions. Our data on ApAQP allow us to provide the first informed explanation of the high water permeability of the CV membrane in amoeba. Moreover, the results suggest that vesicles possessing V‐ATPase are involved in generating an osmotic gradient. Based on our findings, we propose a new hypothesis for the mechanism of CV function. 相似文献
65.
Syeda Shahnaz Parvez Mohammad Masud Parvez Eiji Nishihara Hiroshi Gemma Yoshiharu Fujii 《Plant Growth Regulation》2003,40(2):107-115
The allelopathic potential of the Tamarindus indica L. leaf was investigated through bioassay guided studies using several weed and edible crop species. Both radicle and hypocotyl growth of all the plant species tested was strongly inhibited by the tamarind leaf using a sandwich method. The growth of weed species was reduced more than that of edible crop species. Among the weed species, barnyard grass followed by white clover, and in the edible crop species, lettuce followed by radish ranked top in terms of growth inhibition. Different concentrations of tamarind leaf crude water-soluble extract exhibited a strong inhibition in all the plant species tested and, by contrast, the magnitude of inhibition in the weed species was higher than in edible crop species and ranged from 30–75%. The 10% concentration of the tamarind leaf crude water-soluble extract was most potent against growth of seedlings. The concentrations of the nutrient components were linearly correlated with an increase in the concentration of tamarind leaf crude water-soluble extract. No significant changes in either pH or EC were found in the variations of different concentrations of tamarind leaf crude water-soluble extracts. As compared to control, growth of both radicle and hypocotyl in weed (barnyard grass and white clover) and in edible crop (lettuce and radish) species were significantly reduced when blended tamarind leaves at different concentrations were incorporated into the growth medium. The inhibitory magnitude increased with an increase in the concentration of the tamarind leaf. In terms of growth inhibition, among these tested plants, weed species particularly barnyard grass were most sensitive to the allelochemicals exuded from blended tamarind leaves. When the blended tamarind leaves were removed from the growth medium, all the seedlings grew quickly and the percentage of recovery was between 76–97% of the corresponding controls. Reduction in the fresh and dry weight of these 4 plant species was observed under the experimental conditions, and ranged between 33–42% and 40–53% in the radicle and hypocotyl, respectively. The fresh and dry weight, and total chlorophyll content declined significantly in the incorporated tamarind leaf treatments. Compared to the control, the highest drop in the chlorophyll content of 60% in barnyard grass was observed with the 10% concentration of the leaf treatment. These results clearly indicate that the tamarind leaf contains one or more strong biologically active allelochemical(s) that function as true growth regulator(s) and is involved in plant growth regulation, particularly in weed species. 相似文献
66.
67.
Y Takubo M Okuda I Takemura F Haruna A Sawatari T Nishihara M Kondo 《Microbiology and immunology》1989,33(7):527-538
It was proved that three spore coat proteins of 48, 36, and 22 kDa (P48, P36, and P22) were the components of the outermost layer (OL) of Bacillus megaterium ATCC 12872 spore by analysis of the isolated OL. And it was indicated that these proteins were deposited not by disulfide bond, but by ionic and/or hydrophobic bonds on the spore. Among them, P36 and P22 were expected to be located on the very surface of the spore by immunological analysis. In the OL deficient mutant of B. megaterium ATCC 12872, MAE05, whose spore was lacking in these OL proteins and galactosamine-6-phosphate polymer, both P36 and P22 were present in the mother cell cytoplasm and deposited on the forespores, but they disappeared with the lysis of mother cells. An OL protein-releasing factor having proteolytic activity was detected in the culture supernatant at the late sporulating stage of both the wild-type and the mutant strains. But the factor could not act on the proteins of the mature spores and the forespores at t10 (tn indicates n hr after the end of exponential growth) of the wild-type strain. Moreover, P36 and P22 were found in the spores of a revertant of MAE05 which could form galactosamine-6-phosphate polymer, suggesting that this sugar polymer played the role in protecting the OL proteins against the protease-like substance after the deposition. 相似文献
68.
Tomoaki Nishihara 《Primates; journal of primatology》1995,36(2):151-168
The feeding ecology of western lowland gorillas (Gorilla gorilla gorilla) living in the Nouabalé-Ndoki National Park, northern Congo, was surveyed for one full year. This is the first record to
make clear the seasonal changes in the feeding habits of gorillas in a whole year, living in the primary lowland forest almost
completely undisturbed. Fecal contents, feeding traces, and direct observation were analyzed with reference to a fruit availability
survey. Although the gorillas fed largely on fruits in the forest, their basic diet was fibrous parts of plants, including
shoots, young leaves, and bark. Terrestrial herbaceous vegetation, such as monocotyledons of the Marantaceae and aquatic herbs
having much protein content and minerals, were frequently eaten even in the fruiting season. As these highly nutritious fibrous
foods were superabundant all year, the major foods of the Ndoki gorillas seemed to be those plants. However, they selected
fruits as their alternative food resources in the fruiting season. Gorillas foraged on many fruit species, while showing strong
preferences for some particular species. The swamp forest, including marshy grasslands, was an important and regular habitat
for the Ndoki gorillas. 相似文献
69.
Co-flocculation between cells of beer yeast IFO 2018, a flocculent strain, and non-flocculent strains was investigated by means of a chemical modification method. Treatment with periodate deprived non-flocculent cells, but not flocculent cells, of the ability to co-flocculate. Treatment with mercaptoethanol or photo-irradiation in the presence of methylene blue deprived flocculent cells, but not non-flocculent cells, of the co-flocculating ability. Mercaptoethanol-treated or photoirradiated flocculent cells (beer yeast IFO 2018) co-flocculated with periodate-treated flocculent cells, but periodate-treated cells subsequently subjected to mercaptoethanol treatment or photoirradiation neither flocculated by themselves nor co-flocculated with other cells. Thus, it is likely that both protein and carbohydrate components of the yeast cell surface play important roles in the mutual recognition and intercellular interaction involved in flocculation. It is strongly suggested that the essential carbohydrate which is widely distributed among Saccharomyces species is the mannan fraction on the cell wall, and that a flocculent yeast strain produces surface protein component(s) which recognize and bind the mannan component of adjacent cells. 相似文献
70.
Uptake of nitrogen and production of kainic acid by laboratory culture of the red alga Digenea simplex 下载免费PDF全文
Shanshan Jiang Kazuyoshi Kuwano Gregory N. Nishihara Chisato Urata Ryusuke Shimoda Tomohiro Takatani Osamu Arakawa 《Phycological Research》2018,66(1):68-75
The red alga Digenea simplex was cultured with various culture media to clarify the nutritional conditions to produce kainic acid (KA ). Unlike the domoic acid‐producing red alga Chondria armata , D. simplex was insensitive to excessive manganese, and grew best (mean growth rate approximately 800% for 25 days) in modified PES medium (mPES ; seawater + nitrate, phosphate, iron, trace metals, vitamins, and 2‐[4‐(2‐hydroxyethyl)‐1‐piperazinyl]‐ ethanesulfonic acid) prepared with autoclaved seawater. Liquid chromatography‐mass spectrometry analysis of the algal extracts revealed that the KA content of the explants cultured with mPES or N·P·Fe medium (seawater + nitrate, phosphate, and iron) was somewhat higher than that of wild specimens (1748–2378 μg g?1 vs 1562 μg g?1). The 1H‐nuclear magnetic resonance spectrum of the KA extracted and purified from pooled explants was indistinguishable from the previously reported KA spectrum. When D. simplex was cultured for 6 weeks with medium in which NaNO 3 of mPES was replaced by Na15NO 3, the ratio of 214KA to total measured KA (totalKA = 213KA + 214KA ) in the cultured explants (0.1 at the beginning of culture) gradually increased to 2.5, indicating that D. simplex produces KA in proportion to its growth under the condition in which sufficient nitrogen source is available. 相似文献