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1.
Akihisa Hattori 《Journal of Ethology》2006,24(1):51-57
The distribution patterns of the leathery sea anemone, Heteractis crispa, which contains an algal endosymbiont (zooxanthellae) and anemonefish, were investigated in relation to size distribution on a shallow fringing reef (3.2 ha, 0–4 m depth) in Okinawa, Japan. Individual growth and movements were also examined. Large individuals (>1,000 cm2) inhabited reef edges up to a depth of 4 m, while small anemone (<500 cm2) inhabited shallow reefs including inner reef flats. Individuals rarely moved, and their sizes were significantly correlated with their water depths. Growth of small anemones was negatively correlated with their distance from the reef edge, suggesting that reef edges provide more prey and lower levels of physiological stress. This study suggested that deep reef edges are suitable habitats for H. crispa. Large anemones were inhabited by large Amphiprion perideraion or large Amphiprion clarkii, both of which are effective defenders against anemone predators. Anemones that settle in deep reef edges may enjoy a higher survival rate and attain a large size because of their symbiotic relationship with anemonefish. However, early settlers do not harbor anemonefish. Their mortality rate would be higher in the deep edges than in shallow edges, the complicated topography of which provides refuge. 相似文献
2.
Processing of a plant vacuolar protein precursor in vitro 总被引:4,自引:0,他引:4
3.
Complete Nucleotide Sequence of the Mouse Lactate Dehydrogenase-a Functional Gene: Comparison of the Exon-Intron Organization of Dehydrogenase Genes 总被引:7,自引:0,他引:7 下载免费PDF全文
The complete sequence of 12,851 nucleotides of the mouse lactate dehydrogenase-A (LDH-A) gene has been determined. It includes eight exons, seven introns, promoter and regulatory regions. The B1 repetitive elements present in intron III and VI are oriented in opposite orientation, and they share 72% sequence homology. The exon-intron organization of mouse LDH-A gene is compared with the organizations of other dehydrogenase genes, and the molecular evolution of the nicotinamide adenine dinucleotide binding domains is discussed. 相似文献
4.
5.
It had been previously demonstrated that the oleate activation of synaptosomal membrane phospholipase D liberated choline which was available for acetylcholine formation. The present investigations were undertaken to determine if oleate might have an effect on choline uptake by synaptosomes. It was observed that oleate interfered with choline uptake when incubations were carried out at 37°C but uptake was stimulated at 3°C. Oleate was the most effective fatty acid of several tested. Preliminary observations suggest the presence of a membranous form of choline acetyltransferase. 相似文献
6.
Involvement of tryptase-related cellular protease(s) in human immunodeficiency virus type 1 infection 总被引:28,自引:0,他引:28
Trypstatin, a new cellular Kunitz-type protease inhibitor purified from rat mast cells, inhibited syncytium formation in human immunodeficiency virus type 1 (HIV-1)-infected CCRF-CEM and uninfected Molt-4 clone 8 at a concentration of 1 microM. Anti-rat tongue mast cell tryptase antibodies reacted with Molt-4 clone 8 cells, as determined by Western blot and by immunofluorescence. In addition, the antibody inhibited syncytium formation. These findings along with homologous sequences with trypstatin and a neutralizing epitope of gp120 of HIV-1 suggest that a tryptase-like cellular enzyme(s) is involved in HIV-1 infection. 相似文献
7.
Pierre J. Charest Jiro Hattori Janice DeMoor V. N. Iyer Brian L. Miki 《Plant cell reports》1990,8(11):643-646
Summary Genes coding for the enzyme acetohydroxyacid synthase, often referred to as acetolactate synthase (AHAS, ALS; EC 4.1.3.18), from wild type Arabidopsis thaliana and a sulfonylurea-resistant mutant line GH50 (csrl-1; Haughn et al. 1988) were introduced in Nicotiana tabacum. Both genes were expressed at high levels with the 35S promoter. The csrl-1 gene conferred high levels of resistance to chlorsulfuron whereas the wild type gene did not. As selectable markers, chimaeric AHAS genes yielded transgenic plants on chlorsulfuron but at much lower efficiencies than with a chimaeric neomycin phosphotransferase gene on kanamycin (Sanders et al. 1987). Shoot differentiation from leaf discs was delayed on chlorsulfuron by 4–6 weeks. This study indicated a role for mutant AHAS genes in the genetic manipulation of herbicide resistance in transgenic plants but as selectable markers for plant cells undergoing differentiation no advantage over other genes was perceived. 相似文献
8.
Dr. Takashi Yashiro Motonaka Arai Eiko Miyashita Kayoko Yamashita Takuro Suzuki 《Cell and tissue research》1988,251(2):249-255
Summary Snell dwarf mice display remarkable retardation of growth after birth and are known to lack prolactin (PRL), thyroid stimulating hormone (TSH) and growth hormone (GH). The aim of this study was to determine the reason for these hormonal deficiencies. We examined the fine structure of the gland and its immunohistochemical staining pattern with respect to antisera raised against PRL, TSH, GH, adrenocorticotrophic hormone (ACTH) and luteinizing hormone (LH). The gland of control mice reacted immunohistochemically against all antisera used, whereas only ACTH-producing cells (ACTH cells) and LH-producing cells (LH cells) were distinguished in the dwarf mice. ACTH cells in dwarf mice varied in cell shape, although they were similar in size to those of controls. The distribution of secretory granules in the cytoplasm varied from cell to cell. LH cells in the dwarf mice showed immature features, having poorly developed rough endoplasmic reticulum and Golgi apparatus. The cells were about half the size of controls, and secretory granules were smaller. In dwarf mice, non-granulated cells were encountered in addition to granulated ACTH and LH cells. Some of them formed small clusters, characteristic cell junctions being found between the cells; they thus appeared to be follicular cells. The above results suggest that hormone deficiency in Snell dwarf mice is a result of a defect in the hormoneproducing cells in the gland. 相似文献
9.
Characterization of a human immunodeficiency virus neutralizing monoclonal antibody and mapping of the neutralizing epitope. 总被引:102,自引:79,他引:23 下载免费PDF全文
S Matsushita M Robert-Guroff J Rusche A Koito T Hattori H Hoshino K Javaherian K Takatsuki S Putney 《Journal of virology》1988,62(6):2107-2114
A monoclonal antibody was produced to the exterior envelope glycoprotein (gp120) of the human T-cell lymphotropic virus (HTLV)-IIIB isolate of the human immunodeficiency virus (HIV). This antibody binds to gp120 of HTLV-IIIB and lymphadenopathy-associated virus type 1 (LAV-1) and to the surface of HTLV-IIIB- and LAV-1-infected cells, neutralizes infection by cell-free virus, and prevents fusion of virus-infected cells. In contrast, it does not bind, or weakly binds, the envelope of four heterologous HIV isolates and does not neutralize heterologous isolates HTLV-IIIRF and HTLV-IIIMN. The antibody-binding site was mapped to a 24-amino-acid segment, using recombinant and synthetic segments of HTLV-IIIB gp120. This site is within a segment of amino acid variability known to contain the major neutralizing epitopes (S. D. Putney, T. J. Matthews, W. G. Robey, D. L. Lynn, M. Robert-Guroff, W. T. Mueller, A. J. Langlois, J. Ghrayeb, S. R. Petteway, K. J. Weinhold, P. J. Fischinger, F. Wong-Staal, R. C. Gallo, and D. P. Bolognesi, Science 234:1392-1395, 1986). These results localize an epitope of HIV type-specific neutralization and suggest that neutralizing antibodies may be effective in controlling cell-associated, as well as cell-free, virus infection. 相似文献
10.
Robert G. Rutledge Thérèse Quellet Jiro Hattori Brian L. Miki 《Molecular & general genetics : MGG》1991,229(1):31-40
Summary The Brassica napus rapeseed cultivar Topas contains an acetohydroxyacid synthase (AHAS) multigene family consisting of five members (AHAS 1–5). DNA sequence analysis indicate that AHAS1 and AHAS3 share extensive homology. They probably encode the AHAS enzymes essential for plant growth and development. AHAS2 has diverged significantly from AHAS1 and AHAS3 and has unique features in the coding region of the mature polypeptide, transit peptide and upstream non-coding DNA, which raises the possibility that it has a distinct function. AHAS4 and AHAS5 have interrupted coding regions and may be defective. The complexity of the AHAS multigene family in the allotetraploid species B. napus is much greater than reported for Arabidopsis thaliana and Nicotiana tabacum. Analysis of the presumptive progenitor diploid species B. campestris and B. oleracea indicated that AHAS2, AHAS3 and AHAS4 originate from the A genome, whereas AHAS1 and AHAS5 originate from the C genome. Further variation within each of the AHAS genes in these species was found. 相似文献