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51.
Katsunori Motosaka Masayuki Koganezawa Satoko Narikawa Akira Furuyama Kenji Shinozaki Kunio Isono Ichiro Shimada 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(2):279-283
Acute choice behavior in ingesting two different concentrations of sucrose in Drosophila is presumed to include learning and memory. Effects on this behavior were examined for four mutations that block associative
learning (dunce, rutabaga, amnesiac, and radish). Three of these mutations cause cyclic AMP signaling defects and significantly reduced taste discrimination. The exception
was radish, which affects neither. Electrophysiological recordings confirmed that the sensitivity of taste receptors is almost indistinguishable
in all flies, whether wild type or mutant. These results suggest that food choice behavior in Drosophila involves central nervous learning and memory operating via cyclic AMP signaling pathways. 相似文献
52.
The morphology of eggs and larvae of Awaous melanocephalus is described. The eggs measured 0.33–0.35 mm in long-axis diameter and 0.32–0.34 mm in short-axis diameter. Newly hatched
larvae (0.90–0.99 mm in notochord length, NL; 0.93–1.04 mm in total length, TL) were poorly developed, lacking a mouth and
having a large yolk sac and unpigmented eyes. The mouth opened and the eyes became fully pigmented 3 days after hatching (1.78–2.00 mm
NL, 1.88–2.10 mm TL). The yolk sac was completely absorbed 5 days after hatching at a water temperature of 27°–28°C. 相似文献
53.
We determined the mitochondrial DNA (mtDNA) sequences of two luminous beetles (Arthropoda, Insecta, Coleoptera), Rhagophthalmus lufengensis from Yunnan, China and Rhagophthalmus ohbai from Yaeyama Island, Japan. We identified all the 37 mtDNA genes of R. lufengensis (15,982 bp) and the 34 genes of R. ohbai (15,704 bp). R. lufengensis and R. ohbai genomes have higher A + T contents than other coleopteran genomes although the gene arrangements are similar. Interestingly, in a study of the evolutionary relationship among R. lufengensis, R. ohbai and the firefly Pyrocoelia rufa, the phylogenetic tree inferred from lrRNA genes from mitochondrial genomes indicates a biogeographic relationship among the bioluminescent insects in East Asia and the phylogenetic tree inferred from luciferase-related genes from nuclear genomes shows an appropriate relationship among coleopterans, reflecting the evolutionary origin of bioluminescence. Thus, the mtDNAs of luminescent beetles can provide an insight into their evolutionary origin and biogeography. 相似文献
54.
Kojima K Oshita M Nanjo Y Kasai K Tozawa Y Hayashi H Nishiyama Y 《Molecular microbiology》2007,65(4):936-947
Oxidative stress inhibits the repair of photodamaged photosystem II (PSII). This inhibition is due initially to the suppression, by reactive oxygen species (ROS), of the synthesis de novo of proteins that are required for the repair of PSII, such as the D1 protein, at the level of translational elongation. To investigate in vitro the mechanisms whereby ROS inhibit translational elongation, we developed a translation system in vitro from the cyanobacterium Synechocystis sp. PCC 6803. The synthesis of the D1 protein in vitro was inhibited by exogenous H2O2. However, the addition of reduced forms of elongation factor G (EF-G), which is known to be particularly sensitive to oxidation, was able to reverse the inhibition of translation. By contrast, the oxidized forms of EF-G failed to restore translational activity. Furthermore, the overexpression of EF-G of Synechocystis in another cyanobacterium Synechococcus sp. PCC 7942 increased the tolerance of cells to H2O2 in terms of protein synthesis. These observations suggest that EF-G might be the primary target, within the translational machinery, of inhibition by ROS. 相似文献
55.
56.
Hirokawa YS Takagi A Uchida K Kozuka Y Yoneda M Watanabe M Shiraishi T 《Cellular & molecular biology letters》2007,12(3):370-377
In this paper, we describe the isolation and characterization of two PC3 subclones. One subclone, mr, showed an epithelial
phenotype, the other, M1, showed a sarcomatous morphology. Transplanted into nude mice, mr developed tumors at a dramatically
faster rate than M1. Comparing the two subclones, differentially expressed genes were identified, including E-cadherin, IL-8
and STAG1/PMEPA1. These genes were expressed at higher levels in mr than in M1. 相似文献
57.
Akihiro Matsunaga Masamichi Takami Tarou Irié Kenji Mishima Katsunori Inagaki Ryutaro Kamijo 《Cytotechnology》2015,67(4):727-732
Sintered compounds prepared with β-tricalcium phosphate (β-TCP) are commonly used as biocompatible materials for bone regenerative medicine. Although implanted β-TCP is gradually replaced with new bone after resorption by osteoclasts, exactly how osteoclasts resorb β-TCP is not well understood. To elucidate this mechanism, we analyzed the structure of β-TCP discs on which mouse mature osteoclasts were cultured using scanning electron microscopy. We found that β-TCP was resorbed by mature osteoclasts on one side of each disc, as evidenced by the formation of multiple spine-like crystals at the exposed areas. Because osteoclasts secrete acid to resorb bone minerals, we mimicked this acidification by dipping β-TCP slices into HCl solution (pH 2.0). However, no spine-like crystals appeared even though the size of each β-TCP particle was reduced. On dentin slices, osteoclasts formed clear actin rings, which are cytoskeletal structures characteristic of bone-resorbing osteoclasts. No clear actin rings were observed in osteoclasts cultured on β-TCP slices, although small actin dots were observed. Analysis by transmission electron microscopy showed that osteoclasts attached to β-TCP particles. These results suggest that osteoclasts resorb β-TCP particles independently of clear actin ring formation. 相似文献
58.
Ushiroda K Maruta K Kitoh M Iwai K Nagamine J Tsuchida A Taiji M Nagata R 《Bioorganic & medicinal chemistry letters》2011,21(1):220-224
Starting with a subtle blood glucose-lowering effect of a TGF-β inhibitor, we designed and synthesized a series of benzoylpyrrole-based carboxylic acids as PPARs activators. Among these compounds, 10sNa exhibited favorable blood glucose-lowering effect without body weight gain. We assume that the beneficial effect of 10sNa is attributed to not only its compound PPARα agonistic activity but also its PPARγ partial agonistic activity. 相似文献
59.
Masato Uehara Fumi Kashiwagi Hideyuki Imai Katsunori Tachihara 《Ichthyological Research》2011,58(4):344-349
The age, growth, reproductive condition, and occurrence of natural hybrids of two Nematalosa species around Okinawa Island were examined using 128 specimens obtained from April 2003 to June 2004. Standard length (SL)
reached approximately 150–210 mm within the first 2 years, and then remained stagnant. The maximum age for both sexes was
ca. 5 years old. Maturity sizes and ages were estimated to be at least 173.2 mm SL and 2 years old for females and 192.6 mm
SL and 3 years old for males. Spawnable individuals were mainly observed from January to March based on histological observations
of gonads. Natural hybrids appeared at all sampling sites except for the Haneji Inlet and were dominant at Makiminato (in
south-central Okinawa Island). Their incidence was also quite high (66.9%) in the Makiminato population, when compared with
records for other marine fishes around Japan. In Okinawa Island, these shallow areas are rapidly decreasing in size because
of recent reclamation and land exploitation. Hybrid production may be caused by not only the reproductive biology and sympatric
distributions of the parent species but also recent environmental changes. 相似文献
60.
Miyagi Y Higashiyama M Gochi A Akaike M Ishikawa T Miura T Saruki N Bando E Kimura H Imamura F Moriyama M Ikeda I Chiba A Oshita F Imaizumi A Yamamoto H Miyano H Horimoto K Tochikubo O Mitsushima T Yamakado M Okamoto N 《PloS one》2011,6(9):e24143