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21.
Robert S. Sparkes Hiroyuki Sasaki T. Mohandas Katsuji Yoshioka Ivana Klisak Yoshiyuki Sakaki Camilla Heinzmann Melvin I. Simon 《Human genetics》1987,75(2):151-154
Summary The assignment of the human prealbumin (PALB) gene to chromosome region 18q11–q12.1 has been achieved using a human genomic probe in the study of human-mouse somatic cell hybrids and by in situ hybridization. Because familial amyloidotic polyneuropathy was reported previously to be due to a mutation in prealbumin, it can be inferred that the gene for this disorder also maps to 18q11.2–q12.1. 相似文献
22.
Transgenic tobacco resistant to a bacterial disease by the detoxification of a pathogenic toxin 总被引:6,自引:0,他引:6
Hiroyuki Anzai Katsuyoshi Yoneyama Isamu Yamaguchi 《Molecular & general genetics : MGG》1989,219(3):492-494
Summary Some plant pathogens produce toxins which cause disease in infected plants. One of the pathogenic toxins, tabtoxin, is produced by Pseudomonas syringae pv. tabaci, which causes wildfire of tobacco. A tabtoxin resistance gene (ttr) coding for an acetyltransferase isolated from Pseudomonas syringae pv. tabaci was fused to the 35S promoter of the cauliflower mosaic virus (CaMV) to construct a chimeric gene for introduction into tobacco cells by Agrobacterium-mediated transformation. The transgenic tobacco plants showed high specific-expression of the ttr gene and no chlorotic symptoms caused by tabtoxin treatment or with infection by Pseudomonas syringae pv. tabaci. These results demonstrate a successful approach to obtain disease-resistant plants by detoxification of the pathogenic toxins which play an important role in pathogenesis. 相似文献
23.
Defense mechanisms in invertebrates and fish 总被引:6,自引:0,他引:6
24.
Hiroyuki Matsuda 《Journal of Ethology》1989,7(2):105-112
The evolution of reciprocal cooperation between non-relatives is studied. Food-sharing of vampire bats studied by Wilkinson
(1984) and egg-trading of simultaneous hermaphroditic fish studied by Fisher (1980) are respectively considered as Thompson's
reciprocal assistance and the iterated Hero game. Those models predicted the following: (1) Reciprocal assistance between
adult bats is evolutionarily stable if they repeatedly interact for a long time. However, (2) the cost for an adult to assist
a juvenile is too high to be compensated by the benefit from the juvenile. (3) A particular signal, which determines the sex
role of each partner, is always displayed by a “heroic” partner which releases eggs with a larger cost. (4) If alternation
of sex roles is established, then the evolutionarily stable frequency of displaying a signal of egg-release increases as the
frequency of divorce decreases, and (5) a “cheating” strategy, which releases sperm on every spawning bout, is less advantageous
than reciprocal cooperation. 相似文献
25.
Osamu Kondo Hiroyuki Honda Masahito Taya Takeshi Kobayashi 《Applied microbiology and biotechnology》1989,32(3):291-294
Summary Growth properties of carrot hairy root cells in various bioreactors were investigated. A turbine-blade reactor and an immobilized rotating drum reactor were found to be advantageous for the hairy root culture because of a high oxygen transfer coefficient (k in L a). After 30 days of culture, 10 g/l of dry hairy root cells were obtained in both bioreactors and maximum growth rates (V
m
) were found to be 0.63 and 0.61 g/l per day for the turbine-blade reactor and immobilized rotating drum reactor, respectively. Specific growth rates () at various cultivation times were observed to be linearly proportional to X/k
l
a for both bioreactor configurations where X is the cell concentration. The estimated specific oxygen uptake rate of 0.34 mmol O2/g dry cells per hour compares fairly well with an experimental value of 0.3. 相似文献
26.
Y Nakanishi S Koikeda H Shibata Y Masamune 《Biochemical and biophysical research communications》1989,158(3):685-689
A nuclear extract of Ehrlich ascites tumor cell contains factors binding to two distinct sites in the 5'-upstream region of the adenovirus 12 E1A gene. The gel shift assay was performed for characterization of the binding factors with oligo DNA probes containing sequences corresponding to these sites. The specific binding of a factor to one probe was enhanced when the other oligo DNA was present in excess in the binding reaction. Thus possibly, protein-protein interactions between factors may mutually prevent their binding to target sequences. 相似文献
27.
Regeneration of bovine and octopus opsins in situ with natural and artificial retinals 总被引:4,自引:0,他引:4
Y Koutalos T G Ebrey M Tsuda K Odashima T Lien M H Park N Shimizu F Derguini K Nakanishi H R Gilson 《Biochemistry》1989,28(6):2732-2739
We consider the problem of color regulation in visual pigments for both bovine rhodopsin (lambda max = 500 nm) and octopus rhodopsin (lambda max = 475 nm). Both pigments have 11-cis-retinal (lambda max = 379 nm, in ethanol) as their chromophore. These rhodopsins were bleached in their native membranes, and the opsins were regenerated with natural and artificial chromophores. Both bovine and octopus opsins were regenerated with the 9-cis- and 11-cis-retinal isomers, but the octopus opsin was additionally regenerated with the 13-cis and all-trans isomers. Titration of the octopus opsin with 11-cis-retinal gave an extinction coefficient for octopus rhodopsin of 27,000 +/- 3000 M-1 cm-1 at 475 nm. The absorption maxima of bovine artificial pigments formed by regenerating opsin with the 11-cis dihydro series of chromophores support a color regulation model for bovine rhodopsin in which the chromophore-binding site of the protein has two negative charges: one directly hydrogen bonded to the Schiff base nitrogen and another near carbon-13. Formation of octopus artificial pigments with both all-trans and 11-cis dihydro chromophores leads to a similar model for octopus rhodopsin and metarhodopsin: there are two negative charges in the chromophore-binding site, one directly hydrogen bonded to the Schiff base nitrogen and a second near carbon-13. The interaction of this second charge with the chromophore in octopus rhodopsin is weaker than in bovine, while in metarhodopsin it is as strong as in bovine. 相似文献
28.
29.
Amino acid content in several brain regions of the active and hibernating frog, Rana esculenta 总被引:1,自引:0,他引:1
M Watanabe M Shimada H Watanabe M Nakanishi 《Comparative biochemistry and physiology. B, Comparative biochemistry》1990,97(3):605-610
1. Total free amino acid contents in the optic lobe and diencephalon increased significantly during hibernation. 2. Free glutamate + glutamine showed significant increases in the cerebral hemisphere, optic lobe, medulla oblongata and diencephalon. 3. Free aspartate + asparagine showed significant increases in the cerebral hemisphere, optic lobe, diencephalon and olfactory lobe. 4. GABA showed a significant change only in the medulla oblongata. 5. Total protein amino acid level in the cerebellum and olfactory lobe decreased significantly during hibernation and most of the amino acids decreased significantly in these regions. 6. The amino acid metabolism during amphibian hibernation differs from that of the mammal. 相似文献
30.
Pheromone clouds sprayed by melon fly males were visually detected by focusing a beam of light at them during dusk when the
males were vibrating their wings. The clouds were sprayed to the front, rear and upper sides of the male. We found that special
morphological structures are used for spraying the pheromone clouds. When a male melon fly engages in calling behavior, sex
pheromone droplets are excreted from his anus. This excretion is wiped off with the tarsus of his hind leg, and then it is
deposited on the sexually dimorphic cubital cell hairs on the wing. During wing vibration, the targal bristles on the 3rd
abdominal segment, which are peculiar to males, are rubbed against the specialized hairs of the cubital cell. Calling males
sprayed clouds of pheromone with these actions.
This paper was presented at the 32nd Annual Meeting of the Japanese Society of Applied Entomology and Zoology (Kochi, April,
1988). 相似文献