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1.
Young-Jun Park Tomotaro Nishikawa Norihiko Tomooka Kazuhiro Nemoto 《Molecular breeding : new strategies in plant improvement》2012,30(1):511-520
Polymorphisms at the Waxy locus of Amaranthus caudatus L. collected from a wide range of regions were used to investigate genetic diversity and mutation sites. A comparison of the Waxy locus revealed a very high level of sequence conservation. This result clearly showed low environmental and evolutionary variability in the Waxy gene. We also performed screening to confirm the mutation sites in the coding sequences of all accessions. The results indicate that one insertion in the coding region of Waxy genes was responsible for the change in perisperm starch leading to the waxy phenotype in all accessions of this species, and thus that a single mutation event altered the regulation of the Waxy gene during the domestication of this crop. In addition, phylogenetic analysis showed that waxy phenotypes within each of three species, A. caudatus, A. cruentus and A. hypochondriacus, originated separately or differentiated from nonwaxy phenotypes of each species through a single mutational event (i.e., a frame shift or base substitution). We also compared obvious structural features of the coding sequence of waxy and nonwaxy phenotypes with those of low-amylose phenotypes in A. caudatus. The Waxy coding sequences of low-amylose phenotypes do not show polymorphisms and are identical with those of waxy phenotypes. This could mean that there is another gene that encodes a key enzyme responsible for amylose synthesis as the elementary quantity in tissues other than perisperm in A. caudatus. 相似文献
2.
Masami Takagi 《Oecologia》1985,68(1):1-6
Summary
Pteromalus puparum is a gregarious parasitoid of many butterfly pupae. Adult size, mortality, and sex ratio of P. puparum, as a parasitoid of Papilio xuthus, were unit weight of the host. Effects of female size on fecundity, wing load, and longevity were also examined.The highest total weight of progeny from the host was attained when the number of eggs per gram of the host was approximately 150. Positive correlations were observed between the size of the females and their fecundity and wing load. The maximum longevity of the female kept with honey but without hosts was attained when the initial number of parasitoids per g of the host was 150.Considering the total fecundity of all female progeny, the reproductively most efficient number of eggs to be deposited per g of the host was estimated to be approximately 300. However, as shortage of food for the adult females strongly affects their fecundity, the reproductively most efficient number of eggs to be deposited per g of the host was about 70 when the adult female progeny was not provided with food.The optimal number of eggs to be deposited when the emale oviposits in the host under field conditions is discussed. 相似文献
3.
Immunological memory for T and B cells was studied in an in vitro culture system with spleen cells from mice primed with bovine serum albumin (BSA). Spleen cells taken from mice immunized at various times previously with a single intravenous injection of alum-precipitated (AP) BSA and bacterial endotoxin (ET) were cultured in Marbrook's system with dinitrophenylated (DNP) BSA as the in vitro antigen. In the cultures of spleen cells obtained from mice primed more than 14 days previously, an IgG-predominant anti-BSA response was generated. However, no anti-BSA response was observed in the culture of spleen cells taken from mice primed 7 days previously (day 7 spleen cells). The failure of day 7 spleen cells to generate an antibody response in vitro was shown to be attributable to both the lack of B memory cells and the effect of “suppressive” macrophages induced by ET. On the other hand, anti-BSA memory in the spleen of mice primed with AP-BSA plus ET and 2 months later challenged with AP-BSA matured within 7 days and declined rather quickly by 30 days after the challenge. The difference in the time course of the generation of memory between the spleen cells from primary and from secondary immunized mice might be attributable to the difference in the maturation of memory B cells, since the time course of the development of memory T cells after the secondary immunization was similar to that observed after primary immunization. 相似文献
4.
A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan. 相似文献
5.
Human immunodeficiency virus type-1 (HIV-1) Rev acts by inducing the specific nucleocytoplasmic transport of a class of incompletely spliced RNAs that encodes the viral structural proteins. The transfection of HeLA cells with a rev-defective HIV-1 expression plasmid, however, resulted in the export of overexpressed, intron-containing species of viral RNAs, possibly through a default process of nuclear retention. Thus, this system enabled us to directly compare Rev+ and Rev− cells as to the usage of RRE-containing mRNAs by the cellular translational machinery. Biochemical examination of the transfected cells revealed that although significant levels of gag and env mRNAs were detected in both the presence and absence of Rev, efficient production of viral proteins was strictly dependent on the presence of Rev. A fluoroscence in situ hybridisation assay confirmed these findings and provided further evidence that even in the presence of Rev, not all of the viral mRNA was equally translated. At the early phase of RNA export in Rev+ cells, gag mRNA was observed throughout both the cytoplasm and nucleoplasm as uniform fine stippling. In addition, the mRNA formed clusters mainly in the perinuclear region, which were not observed in Rev− cells. In the presence of Rev, expression of the gag protein was limited to these perinuclear sites where the mRNA accumulated. Subsequent staining of the cytoskeletal proteins demonstrated that in Rev+ cells gag mRNA is colocalized with β-actin in the sites where the RNA formed clusters. In the absence of Rev, in contrast, the gag mRNA failed to associate with the cytoskeletal proteins. These results suggest that in addition to promoting the emergence of intron-containing RNA from the nucleus, Rev plays an important role in the compartmentation of translation by directing RRE-containing mRNAs to the β-actin to form the perinuclear clusters at which the synthesis of viral structural proteins begins. 相似文献
6.
Barbara Tillmann Pierre Jolic?ur Masami Ishihara Nathalie Gosselin Olivier Bertrand Yves Rossetti Isabelle Peretz 《PloS one》2010,5(4)
Congenital amusia is a neurogenetic disorder of music processing that is currently ascribed to a deficit in pitch processing. A recent study challenges this view and claims the disorder might arise as a consequence of a general spatial-processing deficit. Here, we assessed spatial processing abilities in two independent samples of individuals with congenital amusia by using line bisection tasks (Experiment 1) and a mental rotation task (Experiment 2). Both amusics and controls showed the classical spatial effects on bisection performance and on mental rotation performance, and amusics and controls did not differ from each other. These results indicate that the neurocognitive impairment of congenital amusia does not affect the processing of space. 相似文献
7.
Norio Masui Yumie Takagi Tetsu Nishikawa Makoto Yanabe Masato Nose Katsunori Sato 《Experimental Animals》2002,51(5):501-503
A new polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was developed for genetic typing of the mouse Tnfsf6gld mutation. An artificial restriction site was introduced to the mouse Tnfsf6gld mutation by PCR amplification using a modified primer. The three genotypes of the Tnfsf6 locus (Tnfsf6gld/Tnfsf6gld, Tnfsf6gld/+, and +Tnfsf6-gld/+Tnfsf6-gld) could be distinguished clearly and easily. This PCR-RFLP analysis was found to be useful for the identification of the mouse Tnfsf6gld mutation. 相似文献
8.
9.
Masatsugu Hatakeyama Tetsuya Nakamura Kyu Beom Kim Masami Sawa Tikahiko Naito Kugao Oishi 《Development genes and evolution》1990,198(7):389-394
Summary Mature eggs dissected from ovaries of unmated females of Athalia rosae (Hymenoptera: Tenthredinidae), if placed on a filter-paper soaked with distilled water, are activated and develop to haploid males. Occasionally, however, diploid females develop from these artificially activated eggs. Treatment of mature unfertilized eggs dissected from diploid females with ice-cold temperatures immediately before activation and with a high temperature (36° C) upon and immediately after activation resulted in the production of diploid males, diploid females, triploid females and gynandromorphs at high frequency. The same treatment of mature unfertilized eggs dissected from triploid females resulted in the production of only triploid survivors. These results, together with the results on the segregation of a marker mutation, yellow fatbody (yfb), appear to indicate that meiotic divisions were complete in the treated eggs, and that all four nuclei became potentially capable of participating in development with or without automictic fusion.Studies on the sawfly, Athalia rosae (Insecta, Hymenoptera, Tenthredinidae), part V 相似文献
10.
Gastric mucin hydrophobicity: effects of associated and covalently bound lipids, proteolysis, and reduction 总被引:2,自引:0,他引:2
K Gwozdzinski A Slomiany H Nishikawa K Okazaki B L Slomiany 《Biochemistry international》1988,17(5):907-917
The hydrophobic properties of gastric mucus glycoprotein were investigated using the fluorescent probe, bis(8-anilino-1-naphthalenesulfonate). The glycoprotein was subjected to removal of associated and covalently bound lipids, peptic degradation, and disulfide bridge reduction. Fluorescence titration data revealed the presence of 55 hydrophobic binding sites in the intact mucin molecule, 71 binding sites in the glycoprotein devoid of associated lipids, and 53 binding sites in the glycoprotein devoid of associated lipids and covalently bound fatty acids. Proteolytic digestion of the glycoprotein with pepsin essentially abolished the probe binding, while reduction of disulfide bridges resulted in glycoprotein subunits whose combined number of binding sites was about 3 times greater than that of the mucin polymer. The binding of the probe to mucus glycoprotein varied with the pH of the medium, being highest at pH 2.0 and lowest at pH 9.0. The results indicate that lipids contribute to the hydrophobic character of gastric mucin and that hydrophobic binding sites reside on the nonglycosylated regions of the glycoprotein polymer buried within its core. 相似文献