巻号一覧
62 巻, 2 号
選択された号の論文の8件中1～8を表示しています
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Ryu UEDA, Takao KOANA, Tadashi MIYAKE1987 年 62 巻 2 号 p. 85-93
発行日: 1987年
公開日: 2006/07/25
ジャーナル フリーThe Sex Ratio Organism (SRO), a kind of spiroplasma parasitic to the fruit fly Drosophila, proliferated transiently in a primary cell culture from SRO-infected fly embryos. The density of SRO increased more than a hundred times the initial density, reaching 6×105 per μ1 in 3-4 weeks. The serum concentration in the culture media was found to be critical to the SRO proliferation. SRO proliferated in vitro were capable of killing male embryos following their injection into female adult hosts, indicating normal SRO activity in vivo.抄録全体を表示PDF形式でダウンロード (1172K) -
Dong-Sang Sun, Terumi MUKAI1987 年 62 巻 2 号 p. 95-107
発行日: 1987年
公開日: 2006/07/25
ジャーナル フリーTwo hundred and eighty second chromosomes were extracted in the native cytoplasm from the Akayu population, one of the northern populations of D. melanogaster in Japan, and various population-genetic parameters such as effective size of the population (Ne≅5000), frequency of lethal-carrying second chromosomes (Q=0.23), allelism rate of lethol second chromosomes (Ic=0.0137), homozygous detrimental and lethal loads (D=0.235; L=0.263), average degree of dominance of mildly deleterious genes (hE≅O.27), and components of genetic variance for viability-additive (σA2) and dominance (σD2)- (σA2=0.0023; σD2=0.0009) were estimated. The analysis of these data strongly indicates that, in this population, mutation-selection balance is the mechanism for the maintenance of genetic variability of viability. Furthermore, these estimates were compared with those of the Aomori population, whose second chromosomes were extracted in the M type cytoplasm. Since the estimates of the above parameters of both populations were very similar to each other, it was concluded that mutations were not induced due to the P-M type hybrid dysgenesis in the process of extracting the chromosomes. Thus, both the Aomori and Akayu populations can be considered to be a typical northern population in Japan where genetic variabilities of viability are maintained by the balance between mutation and selection pressures.抄録全体を表示PDF形式でダウンロード (1388K) -
Takahiro TAGUCHI1987 年 62 巻 2 号 p. 109-117
発行日: 1987年
公開日: 2006/07/25
ジャーナル フリーA sensitivity to bleomycin was examined in a human leukemic T-cell line (CCRF-HSB2) established from the peripheral blood of a patient with acute lymphoblastic leukemia. At all concentrations of bleomycin tested, HSB2 showed reduced survival and increased chromosome breakage. A normal B-cell line (KS86) and a radiation-insensitive CCRF-HSB2-M cell line were found to be resistant against the effects of bleomycin. The increased sensitivity of the human leukemic T-cell line (HSB2) to bleomycin, as well as to radiation (Shiraishi et al. 1976, 1978; Taguchi and Shiraishi 1983), indicates that HSB2 resembles to ataxia telangiectasia cells in their susceptibility to chromosomal aberration-inducing treatments.抄録全体を表示PDF形式でダウンロード (1019K) -
Toshiya YANAGINO, Yoshihito TAKAHATA, Kokichi HINATA1987 年 62 巻 2 号 p. 119-125
発行日: 1987年
公開日: 2006/07/25
ジャーナル フリーThe restriction enzyme cleavage patterns of chloroplast DNA of eleven diploid species of Brassica and its allied genera were compared by using five restriction endonucleases. A dendrogram of species relationships as shown by the estimated numbers of recognition site mutations was drawn, the species being grouped into three clusters at the 5 recognition site mutations. The clusters did not always correspond to genera recognized in current taxonomy, while good correspondence was observed with the grouping by fraction I protein large subunits. The species relationships as seen with the present method were significantly correlated with those found in cytogenetical studies but not with those based on numerical morphological taxonomy.抄録全体を表示PDF形式でダウンロード (649K) -
Shingo KATO, Koichi MATSUO, Naoyuki NISHIMURA, Naomi TAKAHASHI, Toshiy ...1987 年 62 巻 2 号 p. 127-137
発行日: 1987年
公開日: 2006/07/25
ジャーナル フリーWe determined the complete nucleotide sequence of baboon endogenous virus (BaEV) strain M7. The total length of the retroviral DNA is 8, 507 base pairs. The order of viral proteins encoded is NH2-p12-p15-p30-p10-COON in the gag, NH2-protease-reverse transcriptase-endonuclease-COOH in the pol, and NH2-gp70-p20E-COON in the env genes. The transmembrane env protein, p20E, contains an amino acid sequence closely related to the "immunosuppressive peptide." Uncharacteristically, the pot and env genes do not overlap and are translated in the same frame. The deduced amino acid sequence of BaEV is related to 1) reticuloendotheliosis virus strain A in both the pol and env regions, 2) murine leukemia viruses in the pol but not in the env region, 3) simian type D retroviruses in the env but not in the pol region. This suggests that env genes in retroviruses may have been independently interchanged during evolution.抄録全体を表示PDF形式でダウンロード (1300K) -
Etsuko N. MORIYAMA1987 年 62 巻 2 号 p. 139-147
発行日: 1987年
公開日: 2006/07/25
ジャーナル フリーTo examine whether the rate of nucleotide substitution is affected by generation time of the organism, I attempted to estimate an accurate rate of synonymous (silent) substitution in Drosophila lineages, using alcohol dehydrogenase (Adh) and heat shock protein 82 (hsp82) genes. The results obtained suggest that the rate of synonymous substitution in Drosophila lineages is roughly 10-8 per site per year. This rate is approximately two times higher than that of rodents and ten times greater than higher primates. The higher rate in Drosophila may be explained by the shorter generation times of the Drosophila species, though the possibility that the mutation mechanism in Drosophila may differ from that in mammals cannot be excluded.抄録全体を表示PDF形式でダウンロード (937K) -
Tomohisa HIROBE1987 年 62 巻 2 号 p. 149-158
発行日: 1987年
公開日: 2006/07/25
ジャーナル フリーHair bulb melanocytes involved in the expression of the coat colors of mice are derived from epidermal melanocytes. The biological study of epidermal melanocytes is important to understand the expression of the coat color. Analysis of the melanocyte and melanoblast-melanocyte population in the mouse epidermis has shown marked strain differences, suggesting that the two populations are regulated by genetic factors. From the results of genetic crosses between C57BL/1OJ and C3H/He mice semidominant genes were shown to be involved in regulating the two populations. The two populations in C57BL/1OJ-A/A congenic mouse did not differ from those in C57BL/1OJ. The distributions of the two populations in C3H/He were gradually transferred to those in C57BL/1OJ by repeated backcrossing.
The semidominant genes are thought to affect the melanocyte proliferation, melanocyte differentiation, or induction of tyrosinase activity by MSH. Such effects may change the pigmentation in the hair bulb and produce a variety of the hair color intensity of mice, which may in turn be influenced by selection, mutation, random mating, and environment.抄録全体を表示PDF形式でダウンロード (1018K) -
H. Iyehara OGAWA, Satoshi TSURUTA, Yoshiyuki NIYITANI, Haruhiko MIND, ...1987 年 62 巻 2 号 p. 159-162
発行日: 1987年
公開日: 2006/07/25
ジャーナル フリーTwenty one different metal chlorides have been tested for mutagenicity in the presence of 9-aminoacridine in strains of Salmonella typhimurium. BeCl2, FeCl2, MnCl2, NiCl2, SnCl4, ZnCl2, and ZrCl4, each of which was not mutagenic alone, exhibited mutagenicity when combined with 9-aminoacridine in strains TA1537 and TA2637.抄録全体を表示PDF形式でダウンロード (388K)
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