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Volume 52 (1977)
- Issue 6 Pages 417-
- Issue 5 Pages 327-
- Issue 4 Pages 261-
- Issue 3 Pages 171-
- Issue 2 Pages 87-
- Issue 1 Pages 1-
Volume 52, Issue 2
Displaying 1-9 of 9 articles from this issue
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X. ENHANCEMENT IN FEMALE AND MALE RECOMBINATIONSSUMIO MINAMORI, YUTAKA INOUE, KAZUKO ITO, AKIO SHIMIZU1977 Volume 52 Issue 2 Pages 87-93
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSThe effect of delta, an extrachromosomal element having a mutagenic action, on recombination events was examined. In the presence of this element, the recombination frequency in the second chromosome was increased in females when compared to that in the control, although such an enhancement was not ascertained in the X chromosome. A male recombination was induced in the second chromosome of delta carrying flies, though the frequency was low, being about 0.1%. This recombination was considered to be due to crossover occurring at the meiotic and premeiotic stages.View full abstractDownload PDF (644K) -
KOH-ICHI OHNISHI, SAMUEL H. HORI1977 Volume 52 Issue 2 Pages 95-106
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSThe enzymes having G6PD activity were isolated from 10 species belonging to 8 invertebrate phyla and their properties were examined in order to compare with those of vertebrate G6PD and H6PD. As a result it has been demonstrated that invertebrate G6PD has properties quite similar to vertebrate G6PD in the following respects; (1) The primary substrates are G6P and NADP; (2) Km's for G6P and NADP are in the majority of cases of the order of 10-5M and 10-6M, respectively; (3) Mg ions have no or only a slight stimulative effect; (4) The molecular weight of the monomer is about 55×103 and the enzyme exists as a dimer and/or a tetramer.
No H6PD was found in the species studied.
From these and other data it may be speculated that animal G6PD would not have undergone a marked change in the substrate specificity and in the molecular weight of the monomer during evolution and that echinoderms might be the only one among invertebrates that possesses H6PD. This suggests that if G6PD and H6PD might have a common ancestral molecule, the divergence might have occurred at the time of echinoderm evolution.View full abstractDownload PDF (1397K) -
YOSHIHIKO FURUTA, KOZO NISHIKAWA, TERUO KIMIZUKA1977 Volume 52 Issue 2 Pages 107-115
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSIn oder to consider the phylogeny of wheat and its relatives, nuclear DNA content in 43 strains belonging to section Sitopsis of the genus Aegilops was measured Feulgen-cytophotometrically using pollen tetrad nuclei.
1) Forty three strains showed a graded series of DNA content from the lowest of 180 to the highest of 314, that is, variation of 1.74 fold between both extremes.
2) Significant difference in nuclear DNA content among five taxa were observed and were formulated as follows, sharonensis>longissima=bicornis>speltoides=aucheri.
3) Test of significance on the mean difference between species revealed no difference between Ae. speltoides and Ae. aucheri which are very close relatives with one another.
4) There are intraspecific variations in two species with S1 genome, Ae. longissima and Ae. sharonensis. But Ae. speltoides (S genome) and Ae. aucheri (S) and Ae. bicornis (Sb) had no significant variation within species.
5) Species relationships in section Sitopsis of the genus Aegilops were discussed.View full abstractDownload PDF (815K) -
YOSHIHISA FUJIO1977 Volume 52 Issue 2 Pages 117-124
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSAllelic isozymes were examined in Platichthys stellatus and Kareius bicoloratus collected in Sendai Bay. Of the 32 genetic loci examined, the 9 loci were divergent and the other loci were non-divergent and polymorphic. With one exception, all of these divergent loci were polymorphic in P. stellatus but the commonest alleles were different from these homozygous in K. bicoloratus. The secondary alleles of these loci were identical to those homozygous in K. bicoloratus.
A comparison was made between biochemical and morphological characters to detect natural hybrides in fish populations. The dextral fishes of P. stellatus showed hybrid patterns in all of the 9 divergent loci, indicating that they were F1 hybrids between P. stellatus and K. bicoloratus. From the distribution and frequencies of the secondary alleles in P. stellatus population, an amount of introgression between both species can be estimated.View full abstractDownload PDF (1431K) -
KUNIAKI WATANABE1977 Volume 52 Issue 2 Pages 125-131
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSGenetic stabilisation of diploid-like meiosis occurs in hexaploid, octoploid and decaploid taxa of Chrysanthemum. This stabilisation is ineffective in F1-hybrids between diploids and the several polyploids which have been obtained by ovary culture. The suppression of multivalent formation is effective in even-ploid hybrids although they are amphihaploid. A significant frequency of trivalents occurs in odd-ploid hybrids.View full abstractDownload PDF (1143K) -
YUKIAKI KURODA, AKIKO YOKOIYAMA, TSUNEO KADA1977 Volume 52 Issue 2 Pages 133-147
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSA variant cell line was obtained from Syrian hamster BHK 21 (C-13) cells after twice treatments with EMS and cyclic and continuous selections with 10-2M 5-iodouridine for 5 months. The colony-forming activity, growth rates in the presence of 5-iodouridine, IUdR and BUdR, distribution of chromosome numbers, uptake of 3H-TdR and cell surface properties of the variant cell line were compared with those of the original BHK cell line.
The variant cells were highly resistant to 5-iodouridine and showed cross-resistances to IUdR and BUdR. They grew more slowly and showed a short lag phase in normal medium. They showed a higher growth rate and a shorter doubling time in the presence of 5-iodouridine than in its absence. The variant cells were more severely affected by short-term treatment with irradiated 5-iodouridine than the original BHK cells. Some cells of the variant line had double the chromosome number of the original cells. The variant cells also showed less uptake of 3H-TdR into the cold TCA insoluble fractions than the original cells and differed from the latter in morphology and mutual cohesion. This may be the first observation on the marked cross-resistances of the variant cell line to 5-iodouridine, IUdR and BUdR in cultured mammalian cells.View full abstractDownload PDF (2390K) -
TAKESHI AGATSUMA, TOSHIHIKO SHIROISHI, TAKUJI TAKEUCHI1977 Volume 52 Issue 2 Pages 149-152
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSDownload PDF (278K) -
TADAO MATSUDA1977 Volume 52 Issue 2 Pages 153-157
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSDownload PDF (1943K) -
IV. KARYOTYPES AND C-BANDING PATTERN OF VESPERTILIO ORIENTALISYOSHITAKA OBARA, KAZUO SAITOH1977 Volume 52 Issue 2 Pages 159-161
Published: 1977
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSDownload PDF (1833K)
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