巻号一覧
39 巻, 6 号
選択された号の論文の7件中1～7を表示しています
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I. A POLYHAPLOID PLANT OF AGROPYRON TSUKUSHIENSE VAR. TRANSIENS OHWI FOUND IN A STATE OF NATURESADAO SAKAMOTO1964 年 39 巻 6 号 p. 393-400
発行日: 1964年
公開日: 2007/05/21
ジャーナル フリーAg. tsukushiense var. transiens, a weed growing in fields and along road-sides, is a very common hexaploid species (2n=42), widely distributed in Japan, China, Manchuria and Korea. In a valley of the hilly neighborhood of Misima, a spontaneous polyhaploid plant (2n=21) of the species was found. It was smaller than the hexaploid strains, but its tillering was very vigorous. In natural condition it yielded two seeds which were assumed to have been produced by pollination with the pollen of hexaploid plants growing in its proximity. The two seeds gave two plants, one a monosomic (2n=41) and the other a disomic (2n=42).
Pollen fertility of the polyhaploid, the monosomic and the disomic was 0.001, 28.5 and 78.5%, and seed fertility was 0, 53.3 and 76.6%, respectively. The polyhaploid was crossed by the disomic and by two hexaploid strains, and the crossing success amounted to 0.7-1.6%.
As to chromosome pairing at MI of PMCs, the polyhaploid showed 21I in 84% and 1II+19I in 14% of 442 cells observed. In the majority of cells chromosome pairing in the monosomic was 20II+1I. From the result it is concluded that Ag. tsukushiense var. transiens is an allohexaploid whose genome constitution comprises three different genomes. Summarizing the cytological studies of polyhaploids in Agropyron, the types of polyploidy in this genus are assumed to be various and complex.抄録全体を表示PDF形式でダウンロード (1460K) -
HIDEO KIKKAWA1964 年 39 巻 6 号 p. 401-411
発行日: 1964年
公開日: 2007/05/21
ジャーナル フリーIn D. melanogaster, there can be detected at least seven amylase bands (isozymes) on agar-gel zymograms. They are called Nos. 1-7 from the anode side (Figure 1). Amylase patterns are specific according to strains. For example, the Amy1 strain shows only one strong amylase band No. 1, whereas the Amy2.6 strain shows two strong bands, Nos. 2 and 6. At present, seven strains with different amylase patterns have been established.
Amylase patterns of these strains are always controlled by a gene or genes linked very closely at locus 78 on the second chromosome. They are probably allelic and co-dominant with one another.
The F1 individuals between any two strains with different amylase patterns, show only mixed bands of the parental patterns, that is, no hybrid band has been detected on the zymogram.
Studies on amylase isozymes may contribute not only to the problem of population genetics of D. melanogaster, but also to the evolutionary history of the genus Drosophila.抄録全体を表示PDF形式でダウンロード (2100K) -
II. CHROMOSOME STUDIES IN EIGHT CASES OF SCHIZOPHRENIATETSUJI KADOTANI, KEISHI MUNECHIKA1964 年 39 巻 6 号 p. 412-415
発行日: 1964年
公開日: 2007/05/21
ジャーナル フリーEight cases of schizophrenia were studied with respect to their chromosome constitutions, based on short-term cultures of leucocytes from peripheral blood. All cases showed no visible change or detectable variation from a normal chromosome complement.抄録全体を表示PDF形式でダウンロード (447K) -
I. GENETIC ANALYSIS OF TETRALTERA-TYPE MUTATIONSUKEICHI FUJII, MASATA KAWABE, IWAO IWAMURA1964 年 39 巻 6 号 p. 416-421
発行日: 1964年
公開日: 2007/05/21
ジャーナル フリーFlies of a new mutant with wings transformed into halter-like or other shaped appendages were found by T. Kanehisa in the wild strain of Drosophila virilis collected at Sapporo (Hokkaido, Japan). Phenotypical changes are observed also on the thorax and the scutellum. As the mutation phenotypically resembles the “tetralteraBd” of Drosophila melanogaster reported by R. B. Goldschmidt, we named the mutation “tetraltera” (tet). Flies homozygous for tet show a penetrance of about 10 percent, whereas about 0.2 percent of flies heterozygous for the mutation show the mutant phenotype. It is determined that the tet gene is situated on the fourth chromosome, but the locus is not yet definitely determined. Another mutation which looked like tet was found in the Notch3a stock of D. virilis. This mutant strain has a low penetrance of about 0.07 percent and flies heterozygous for the gene phenotypically show the wild-type. The gene of this mutation is supposed to belong to the second linkage group, though there is some uncertainty about this because of its extremely low penetrance.抄録全体を表示PDF形式でダウンロード (487K) -
KAZUYOSHI KIRITANI, YONOSUKE IKEDA1964 年 39 巻 6 号 p. 422-432
発行日: 1964年
公開日: 2007/05/21
ジャーナル フリーThe reductoisomerase in the biosynthetic pathway leading to isoleucine and valine is represed by L-valine, but not by isoleucine in Escherichia coli K-12. The mode of repression in a methionine-requiring mutant is different from that of wild type. The reductoisomerase of the methionine-requiring mutant and its derivatives, the isoleucine-valine requiring mutants, is repressed by valine to a low level, if the molar ratio of L-isoleucine to L-valine in the medium is below 1. On the other hand, the synthesis of the reductoisomerase in the wild-type strain is gradually decreased by increasing amounts of L-valine in media containing a constant amount of L-isoleucine. The repression by L-valine is specific for the reductoisomerase and independent of the induction of β-galactosidase.抄録全体を表示PDF形式でダウンロード (904K) -
大図 英二1964 年 39 巻 6 号 p. 433-439
発行日: 1964年
公開日: 2007/05/21
ジャーナル フリーハツカネズミの発生初期の卵子におよぼす X 線の影響を調査する目的で, 受精後の12時間目 (0.5日) および36時間目 (1.5日) の dd×CBA の F1 の交配雌に X 線を照射し, その胎児を観察した。X 線は 5r, 15r および 25r の線量を用いた。
1) 着床後早期の死亡胎児は線量に比例して増大したのに対し, 着床後後期の死亡胎児は線量による関係はみられなかった。
2) 着床後早期の死亡胎児は, 受精後0.5日目の照射区において, 受精後1.5日目の照射区より増大した。
3) 照射された胎児1001個体から8個体の脱脳症と2個体の後肢に多指症をもった胎児が検出された。
4) 前肢の第5指の基部に小さな突起をもった多くの奇形胎児が, 照射区および対照区から検出された。
5) 組織学的観察の結果, 前肢に異常をもつた胎児は, その異常部の中心部にいずれも軟骨組織がみられた。抄録全体を表示PDF形式でダウンロード (1742K) -
V. 線量, 分割照射, 低温照射からみた花色変化斑点の誘発機構について根津 光也1964 年 39 巻 6 号 p. 440-446
発行日: 1964年
公開日: 2007/05/21
ジャーナル フリーThe tulip flower develops inside the bulb during storage, and the color spots appearing on the perianth were induced by gamma-irradiation. If irradiation was carried out in the critical period shortly before the completion of perianth formation, the color spots appeared at random in single or a few epithelial cells. As previously reported, the extent of mutation was reduced at low intensity as compared with high intensity exposure. Therofore, the spots are considered to be due to somatic mutation of epithelial cell being caused by chromosomal deletion through irradiation.
In the present paper, in order to elucidate the nature of the genetic change, i, e., whether genic or chromosomal, quantitative studies of total dose, fractionation and temperature effects on the somatic mutation have been studied. The results are summarized as follows:
1) The data refer to the number of mutant cells per unit area. Therefore, growth inhibition of the perianth was undesirable. But measurements of the size of perianth showed very rarely inhibition after irradiation by 200r in total dose in October.
2) Cell division of the epithelium at the time of irradiation, in October and November, was estimated from the average number of mutant cells per spot, which was 1.13 and 1.02 at 200r, respectively. These figures indicate that the epithelial cells of the perianth may not undergo division after November.
3) Frequency of color spot occurrence after single acute exposure was examined at doses of 25 to 200r at 600r/h. The dose response curve is rather exponential.
4) A total dose of 100 or 200r was fractionated into 2 or 4 doses of 50r and 100r, respectively, and with intervals of 30 to 1440 minutes and the effects were compared with that of single dose. No reduction of mutation was observed when the interval lasted 30 minutes, while in the case of fractionation into 4 doses at the same interval, the number of mutations was reduced as compared with a single dose. When the interval lasted 1440 minutes at the total dose of 100r and 200r, the number of mutation was markedly reduced to that obtained at non-fractionated dose.
5) The number of mutations increased at low temperature (-2° to 2°C) during irradiation as compared with that obtained at 12.5°C. These results show that chromosome reunion after deletion may be involved in the color spot formation induced by gamma-rays.抄録全体を表示PDF形式でダウンロード (662K)
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