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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.
The number of mast cells in connective tissue from dorsal skin varied markedly among mouse strains. Inbred strains of mice were typed into three groups, high (NC and NZB mice), low (B6, B10, and BALB/c mice), and intermediate (C3H/He and DBA/2 mice), by their mast cell content in the skin. However, the strain differences in the number of mast cells was marginal at the age of weaning but became distinct with age. This could be explained mainly by the frequently observed clustering of mast cells in adult NC and NZB mice and the rarely observed clustering in younger mice as well as in adult B10 and BALB/c mice. The breeding experiment revealed that the difference in the number of mast cells between NC and B10 mice was controlled by a single autosomal dominant locus, for which we propose the designation Mcr (mast cell regulator). The role of the Mcr locus with regard to the frequency of the mast cell population in connective tissue is discussed. 相似文献
3.
Processing of a plant vacuolar protein precursor in vitro 总被引:4,自引:0,他引:4
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.
Linda Owers Narhi Michael F. Rhode Pamela Hunt Tsutomu Arakawa 《Journal of Protein Chemistry》1989,8(5):669-677
The limited proteolysis of human recombinant TNF- by trypsin yields two stable products resulting from cleavage after Arg6 and Arg44. In solution these two products remain associated together in a trimer with a Stokes' radius slightly greater than the radius of intact TNF- and, therefore, could not be separated from each other under nondenaturing conditions. This limited digest retains at least 20% of the activity of the original TNF- sample, and has a tertiary structure that is similar to that of the native protein by circular dichroism. On the other hand, incorrectly folded, inactive TNF- undergoes extensive digestion following similar treatment with trypsin. These results indicate that the active form of TNF- has a tight core structure which is maintained afterN-terminal cleavage and removal. 相似文献
7.
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
8.
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
9.
The maximum theanine production by Camellia sinensis cultured cells was achieved by culturing in the modified MS medium containing 2 mg/l indole-3-butyric acid, 0.1 mg/l kinetin, 0 mM NH4NO3 and 39.6 mM KNO3 with 40 mM ethylamine hydrochloride or 20 mM ethylamine hydrochloride and 10 mM L-glutamic acid. Other primary amines, such as methylamine, n-butylamine, 2-hydroxyethylamine, 2cyanoethylamine, aniline, benzylamine and phenylethylamine, were also biotransformed to N5-alkyl-L-glutamine derivatives by C. sinensis cultured cells.Abbreviations IBA
indole-3-butyric acid
- K
kinetin
- MS medium
Murashige and Skoog's basal medium (1962)
- NMR
nuclear magnetic resonance
Part 70 in the series Studies on Plant Tissue Culture. For Part 69 see Furuya et al. (1990). 相似文献
10.
Primary structure of rat liver alkaline phosphatase deduced from its cDNA. 总被引:5,自引:1,他引:4
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Rat liver alkaline phosphatase (ALP) was markedly induced by treatment of rats by bile-duct ligation and colchicine injection. Taking this advantage for enrichment of ALP mRNA, we constructed a lambda gt11 liver cDNA library using polyadenylated RNA prepared from the treated rat liver, and isolated an ALP cDNA clone. The 2165 bp cDNA contained an open reading frame that encodes a 524-amino-acid-residue polypeptide with a predicted molecular mass of 57737 Da. The precursor protein contained a presumed signal peptide of 17 amino acid residues followed by 28 amino acid residues identical with the N-terminal sequence determined from the purified rat liver ALP. It was also confirmed that amino acid sequences of two CNBr-cleavage peptides obtained from liver ALP were contained within the cDNA-encoded protein. Five possible N-linked glycosylation sites were found in the molecule and a highly hydrophobic amino acid sequence at the C-terminus. The deduced polypeptide of rat liver ALP showed 88% homology to that of the human liver-type enzyme in osteosarcoma cells. RNA blot hybridization analysis identified a single species of ALP mRNA with 2.7 kb in both the control and the treated rat livers. An approx. 20-fold increase of the mRNA was detected in the treated liver at 12 h after the onset of stimulation, compared with that in the control liver. 相似文献