巻号一覧
60 巻, 5 号
選択された号の論文の10件中1～10を表示しています
- |<
- <
- 1
- >
- >|
-
III. Frequency of sterility mutants in Japanese populationsOhmi OHNISHI1985 年 60 巻 5 号 p. 391-404
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーThe incidence of recessive male and female sterility mutants concealedin cultivated buckwheat populations in Japan was estimated by examining the segregation of such mutants in about 2000 full-sib families. The incidence per gamete varied among the populations, in contrast with a rather uniform incidence of chlorophyll-deficient mutants. The average incidence of female sterility mutants was 11.7%, with a range of 1.6-21.9%, while that of male sterility mutants was 8.3%, with a range of 2.0-14.5%. In addition to these, male semisterility mutants were also segregating in the populations; their incidence ranged from 0.0 to 19.3%, with an average of 9.4%. The Geihoku and several other populations showed an extremely high incidence of sterilizing mutants; this raised the possibility that there were several segregating loci, each with a mutant allele frequency greater than 0.01. This was investigated by comparing the incidence of sterilizing mutants per gamete with the frequency of recessive homozygotes in randomly mating populations. Although some mutants affected both male and female sterilities simultaneously, most mutants affected either the male or the female organs alone. By combining previous studies with the present one, the total genetic load carried by buckwheat populations was estimated to be 1.96 lethal equivalents per gamete, which falls within the range previously reported for outcrossing angiosperm species. This load comes mostly from the detrimental effects of mutants at the reproductive stage, that is, male and female sterilizing mutants and polygenes reducing the number of seeds per plant. The genetic loads expressed at the germination and seedling stages were also large, 0.23 and 0.25 lethal equivalents per gamete, respectively, but they consisted of only one fourth of the total load.抄録全体を表示PDF形式でダウンロード (1500K) -
Ryuso TANAKA, Kenji TANIGUCHI, Yasuko KAMISUGI1985 年 60 巻 5 号 p. 405-410
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーSingle cells in a free and suspended state were induced from the tissue cultured shoot primordia of Haplopappus gracilis (2n=4). New shoot primordia were formed from the suspensions of single cells, when the suspensions were cultured in the conditions of original shoot primordia reported by Tanaka and Ikeda (1983). A new path of micropropagation in somatic life cycle in plant tissue culture was proposed, that is shoot primordia→suspensions of single cells→regenerated shoot primordia→plantlets→shoot primordia.抄録全体を表示PDF形式でダウンロード (1434K) -
I. Phylogenetic relationships among ten cereals revealed by the restriction fragment patterns of chloroplast DNAShin-ichiro ENOMOTO, Yasunari OGIHARA, Koichiro TSUNEWAKI1985 年 60 巻 5 号 p. 411-424
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーThe phylogenetic relationship of ten crops selected from all the seven tribes of the Gramineae which contain crop species, i.e., wheat, rye and barley from Triticeae, oats from Agrosteae, finger millet from Chlorideae, foxtail millet from Paniceae, sorghum from Andropogoneae, maize and job′s tears from Maydeae, and rice from Oryzeae, were studied by restriction endonuclease analysis of their chloroplast (ct) DNAs. Three enzymes, KpnI, PstI and SalI which are known to give rise to fewer restriction fragments from the cereal ctDNAs than other enzymes were used. For each restriction fragment pattern, the copy number and molecular size of the individual fragments were estimated. From these data, genetic distance (p) between chloroplast genomes of the ten cereals were calculated using Engels′ formula (Engels 1981), based on which their phylogenetic tree was constructed by the UPGMA method of Sneath and Sokal (1973). This phylogenetic tree is in complete agreement with that made from ordinary systematic studies (Tateoka 1957), except for one point, i.e., the genetic distance between the chloroplast genomes of sorghum and maize or job′s tears which belong to different tribes is closer than that between maize and job′s tears which belong to the same tribe. Thus, the two genera, Zea and Coix appear to be better placed in separate tribes. The critical p value to separate two taxa into different tribes, subfamilies and families was about p=0.02, 0.05 and 0.12, respectively.抄録全体を表示PDF形式でダウンロード (1674K) -
Ken NOZAWA, Masanobu FUKUI, Toshinori FURUKAWA1985 年 60 巻 5 号 p. 425-439
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーBlood samples were collected from "alley" or feral populations of cats in four prefectures of Japan, and genetic variation at 31 blood-protein loci were examined by starch-gel electrophoreses. The proportion of polymorphic loci and the average heterozygosity were estimated as 0.2580-0.3548 (mean: 0.2903) and 0.0741-0.0917 (mean: 0.0793), respectively, Whereas these values are on a standard level of the genetic variability of domesticated animals, they are conspicuously higher compared with those of such wild mammals as Japanese macaque and Japanese serow. Amount of genetic differentiation among the prefectural populations was evaluated with the FST and GST statistics as 0.0075 and 0.0112, respectively. These values are more than one order lower than those among local subpopulations of the Japanese macaques, suggesting that the gene constitution of Japanese cats are fairly homogeneous over the country.抄録全体を表示PDF形式でダウンロード (1228K) -
Masanobu ITOH, Samuel H. HORI1985 年 60 巻 5 号 p. 441-453
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーAn X-linked regulatory mutation in Drosophila melanogaster which gives rise to constitutive expression of the G 6 PD gene appears to have resulted from insertion of a novel class of transposable genetic elements into the vicinity of the G 6 PD locus. Flies carrying this element exhibit a very high level of G 6 PD activity, and linkage of this element to the X chromosome is stable as long as the mutants are inbred. However, loss of the high-G 6 PD activity trait, probably due to excision of the inserted element, often occurs when the mutant males are mated with females of other strains showing a normal level of G 6 PD activity (hence lacking in the element), but not in the reciprocal crosses. This suggests that the cytoplasm of the mutant might possess some factors which stabilize the regulatory element, and that the element itself might be responsible for the production of this stabilizing factor.抄録全体を表示PDF形式でダウンロード (1345K) -
Samuel H. HORI, Masami AKASAKA, Hiroki ITO, Takaomi HANAOKA, Soichi TA ...1985 年 60 巻 5 号 p. 455-463
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーMixtures of 17-base long oligonucleotides possibly encoding a hexapeptide of Drosophila melanogaster glucose-6-phosphate dehydrogenase were synthesized and used as probes for screening a genomic library of D. melanogaster constructed in Charon 4A vectors. A total of about 60, 000 plaques were initially screened, and after two successive plaque purification three clones carrying the identical 13-kb EcoRI fragment were isolated. That these clones contain the G6PD coding sequence was demonstrated by in situ hybridization of the cloned DNA fragments to salivary gland polytene chromosomes and in vitro translation of the hybrid-selected mRNA. As suggested by Torczynski et al. (1984), this method using short synthetic probes appears versatile for isolating low-copy genes from genomic libraries.抄録全体を表示PDF形式でダウンロード (2480K) -
Kanji ONO, Tohru TAKAHARA1985 年 60 巻 5 号 p. 465-473
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーSix chlorate-resistant (CR) cell lines were established from survivors after plating mutagenized and non-mutagenized cells of Kp20, a Paeonia haploid cell line, onto solid medium containing 30mM KClO3 and amino acids as the sole nitrogen source (AA-chlorate medium). Five millimolar N-ethyl-N-nitrosourea (ENU) was used as the mutagen. None of the 6 CR lines grew on medium containing nitrate as the sole nitrogen source (NO3-medium). Of these CR lines, 5 completely lacked in vivo nitrate reductase (NR) activity and one showed low (about 11% of that of the wild type) NR activity. In all CR lines except for one, the percentage occupied by haploid cells increased to 83-95% compared with 73% in the wild type. This suggested that mutation may have occurred to advantage in the haploid cells.抄録全体を表示PDF形式でダウンロード (1298K) -
Midori MATSUMOTO, Norio ICHIKAWA, Shigeo TANAKA, Takashi MORITA, Aizo ...1985 年 60 巻 5 号 p. 475-483
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーIt was reported that φ80 lysogens did not adsorb superinfecting phage φ80 and a gene responsible to the phenomenon was named cor (Kozyrev et al., 1982). We found that E. coli containing φ80 genome in lytic cycle also began to show resistance to superinfecting φ80 after 5min of infection. We cloned the cor gene and determined its nucleotide sequence. A putative cor gene product should be 92 amino acids long and have three hydrophobic cores and one hydrophilic region, indicating a possibility of membrane binding protein. The product may interact with φ80 receptor on inner- or outer-membrane of E. coli cells and inhibit the adsorption of superinfecting φ80. The cor gene is supposed to be transcribed from a unique promoter located close to the gene.抄録全体を表示PDF形式でダウンロード (906K) -
III. Nucleotide sequence analysis of tetracycline resistance gene of pAMα1 and ori-177Hiromi ISHIWA, Harue SHIBAHARA1985 年 60 巻 5 号 p. 485-498
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーA small plasmid pHY163PLK (2519bp) was constructed from the shuttle vector pHY300PLK. pHY163PLK contains the replication origin of pACYC-177, the tetracycline resistance gene (tetα1) of pAMα1 derived from Streptococcus faecalis and eight continuous unique cloning sites of a polylinker region (EcoRI, SmaI, BamHI, SalI, PstI, BglII, XbaI and HindIII). pHY163PLK, a copy-number mutant, has one base substitution in RNA I region compared with that of p15A which is the ancestor of ori-pHY163PLK. The tetα1, which codes 458 amino acids (1374bp), is highly homologous to the TcR genes of other Gram-positive bacteria but completely different from the TcR gene encoded by pBR322 in Gram-negative bacteria. The regulatory region of tetα1 (constitutive type) has an insertion of seven base pairs in the leader peptide region of a related inducible TcR gene. (key words: tetracycline resistance gene; pAMα1; Streptococcus; nucleotide sequence; amino acid sequence)抄録全体を表示PDF形式でダウンロード (1387K) -
Yoko SATTA, Takashi GOJOBORI, Takeo MARUYAMA, Kaoru SAIGO, Sadao I. CH ...1985 年 60 巻 5 号 p. 499-503
発行日: 1985年
公開日: 2006/07/25
ジャーナル フリーWith aid of a computer, each of the four open reading frames (ORFs) in the P-transposable element of Drosophila melanogaster was aligned with the amino acid sequence of the transposase (TnpA) of bacterial transposon Tn3. The four ORFs, named ORF0, -1, -2, and - 3 lined in this order from 5′ to 3′ direction in the P element, turned out to have on the average 18 percent homologies with the Tn3 transposase in the same order without much overlap between adjacent ORFs. Based on the comparison with consensus sequences at exon-intron junctions, three possible introns were predicted in the P element. Each of these putative introns covers the region between adjacent ORFs and these splicings do not alter the initially predicted reading frames. It appears, therefore, that a mature mRNA processed from the transcript of the whole P element codes a single polypeptide having homology to TnpA. This suggests that the P element and the TnpA gene may have diverged from a common ancestor. Taking account of our previous finding that the resolvase of Tn3 has sequence homology with ORF1 of the P element, evolutionary relationships among the P element, the resolvase gene and the TnpA gene were discussed.抄録全体を表示PDF形式でダウンロード (573K)
- |<
- <
- 1
- >
- >|