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111.
Paired fins and associated internal structures of the epauletic sharkHemiscyllium ocellatum, were described on the basis of three specimens. A comparison with other genera showed the epaulette shark to be, characterized
by two elongated basal cartilages articulating with a distally projecting articular condyle on the coracoid, a loosely separated
radial series with an intermediate series, a levator pectoralis inferior muscle and an anterolaterally developed depressor
pectoralis muscle in the pectoral fin, and an elongated anterior pelvic basal cartilage articulating with a distally projecting
articular condyle and an anterolaterally developed depressor pelvicus muscle in the pelvic fin. In captivity, the sharks exhibited
both upright and crawling behavior on the bottom by using the pectoral and pelvic fins and bending the body. The distinctive
morphological characters are shared by otherHemiscyllium species and are suggested as important factors enabling their unique behavior associated with a complex coral reef habitat. 相似文献
112.
OsHKT1;5 mediates Na+ exclusion in the vasculature to protect leaf blades and reproductive tissues from salt toxicity in rice
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113.
Fujioka T Kaneko F Kazama T Suwabe K Suzuki G Makino A Mae T Endo M Kawagishi-Kobayashi M Watanabe M 《Genes & genetic systems》2008,83(3):281-284
Small RNAs including microRNA (miRNA) and small interfering RNA (siRNA) are known as repressors of gene expression. There are many plant proteins involved in small RNA-mediated gene silencing, such as Dicer ribonucleases and RNA-dependent RNA polymerases. However, most of these proteins have been reported to be absent in the late developmental stage of the plant male gamete, pollen. In order to clarify the existence of the small RNAs during maturation of pollen, we cloned and sequenced small RNAs from rice anthers including tricellular pollen. From fifty six candidates of small RNAs, we identified two known miRNAs (miR166 and miR167), eight potential miRNAs, and ten putative heterochromatic siRNAs (hc-siRNAs). RNA gel blot analyses clearly showed that miR166 and miR167 were accumulated in the uninuclear pollen stage of anther development and remained until the tricellular pollen stage. Our cloning and RNA gel blot analyses of small RNAs led us to propose a possible function of small RNA-mediated gene regulation for the development of male gametes in rice. 相似文献
114.
Wakao M Saito A Ohishi K Kishimoto Y Nishimura T Sobel M Suda Y 《Bioorganic & medicinal chemistry letters》2008,18(7):2499-2504
Carbohydrate chip technology has a great potential for the high-throughput evaluation of carbohydrate-protein interactions. Herein, we report syntheses of novel sulfated oligosaccharides possessing heparin and heparan sulfate partial disaccharide structures, their immobilization on gold-coated chips to prepare array-type Sugar Chips, and evaluation of binding potencies of proteins by surface plasmon resonance (SPR) imaging technology. Sulfated oligosaccharides were efficiently synthesized from glucosamine and uronic acid moieties. Synthesized sulfated oligosaccharides were then easily immobilized on gold-coated chips using previously reported methods. The effectiveness of this analytical method was confirmed in binding experiments between the chips and heparin binding proteins, fibronectin and recombinant human von Willebrand factor A1 domain (rh-vWf-A1), where specific partial structures of heparin or heparan sulfate responsible for binding were identified. 相似文献
115.
Miura T Kurihara K Furuuchi T Yoshida T Ajito K 《Bioorganic & medicinal chemistry》2008,16(7):3985-4002
Design and synthesis of 16-membered macrolides modified at the C-12 and 13 positions are described. The compounds we report here have an arylalkylamino group attached to the C-12 position of the macrolactone. Both types of derivatives, 12,13-cyclic carbamates and non-carbamate analogues, were synthesized via 12-amino-13-hydroxy intermediates derived from 12,13-epoxide that was prepared by selective epoxidation at the C-12 and C-13 positions. 4'-Hydroxyl analogues were also prepared by acidic hydrolysis of a neutral sugar. These compounds were evaluated for in vitro antibacterial activity against respiratory tract pathogens. Some of these analogues exhibited an improved activity compared with the corresponding parent compound. 相似文献
116.
Biologists postulate that sexual dimorphism in the brain underlies gender differences in behavior, yet direct evidence for this has been sparse. We identified a male-specific, fruitless (fru)/doublesex (dsx)-coexpressing neuronal cluster, P1, in Drosophila. The artificial induction of a P1 clone in females effectively provokes male-typical behavior in such females even when the other parts of the brain are not masculinized. P1, located in the dorsal posterior brain near the mushroom body, is composed of 20 interneurons, each of which has a primary transversal neurite with extensive ramifications in the bilateral protocerebrum. P1 is fated to die in females through the action of a feminizing protein, DsxF. A masculinizing protein Fru is required in the male brain for correct positioning of the terminals of P1 neurites. Thus, the coordinated actions of two sex determination genes, dsx and fru, confer the unique ability to initiate male-typical sexual behavior on P1 neurons. 相似文献
117.
The specialization of herbivores among tree species is poorly understood despite its fundamental importance as a factor regulating
diversity. To examine the effect of tree species on larval community structure, the larval communities in 10 temperate deciduous
tree species that differed in leaf emergence pattern (flush- vs. intermediate-type) were seasonally surveyed. The newly developed
soft, nitrogen-rich leaves of all species became tough and nitrogen-poor as the season progressed. Following the changes in
leaf quality, two distinct seasonal lepidopteran larval communities emerged, with a marked turnover in early July. The beta
diversity, or dissimilarity, of species composition in the larval communities among tree species was higher in summer than
in spring. These results imply that the lepidopteran larval communities as a whole were supported by alpha diversity in spring
and by beta diversity in summer, demonstrating that the plant diversity of this forest could support a caterpillar community.
We examined the importance of spatio-temporal variations in leaf quality within and among tree species in promoting herbivore
diversity, although other factors, such as tree species phylogeny and predators, may also have a large effect on lepidopteran
larval communities. 相似文献
118.
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120.
Ikeda H Watanabe N Ishii I Shimosawa T Kume Y Tomiya T Inoue Y Nishikawa T Ohtomo N Tanoue Y Iitsuka S Fujita R Omata M Chun J Yatomi Y 《Journal of lipid research》2009,50(3):556-564
Sphingosine 1-phosphate (S1P), a bioactive lipid mediator, stimulates proliferation and contractility in hepatic stellate cells, the principal matrix-producing cells in the liver, and inhibits proliferation via S1P receptor 2 (S1P(2)) in hepatocytes in rats in vitro. A potential role of S1P and S1P(2) in liver regeneration and fibrosis was examined in S1P(2)-deficient mice. Nuclear 5-bromo-2'-deoxy-uridine labeling, proliferating cell nuclear antigen (PCNA) staining in hepatocytes, and the ratio of liver weight to body weight were enhanced at 48 h in S1P(2)-deficient mice after a single carbon tetrachloride (CCl(4)) injection. After dimethylnitrosamine (DMN) administration with a lethal dose, PCNA staining in hepatocytes was enhanced at 48 h and survival rate was higher in S1P(2)-deficient mice. Serum aminotransferase level was unaltered in those mice compared with wild-type mice in both CCl(4)- and DMN-induced liver injury, suggesting that S1P(2) inactivation accelerated regeneration not as a response to enhanced liver damage. After chronic CCl(4) administration, fibrosis was less apparent, with reduced expression of smooth-muscle alpha-actin-positive cells in the livers of S1P(2)-deficient mice, suggesting that S1P(2) inactivation ameliorated CCl(4)-induced fibrosis due to the decreased accumulation of hepatic stellate cells. Thus, S1P plays a significant role in regeneration and fibrosis after liver injury via S1P(2). 相似文献