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The pollen-stigma interaction of self-incompatibility in crucifers is correlated with glycoproteins localized in the cell wall of the stigmatic papillae that are encoded by the S locus glycoprotein (SLG) gene. When fused to the [beta]-glucuronidase (GUS) reporter gene, the 5[prime] upstream regulatory region of SLG directed high level expression in the papillae of transgenic Brassica plants. Histochemical and fluorometric assays revealed that, in addition to its primary site of expression in the stigmatic papillae, the SLG-GUS fusion was also expressed in the transmitting tissue of stigma, style, and ovary, and in anthers. This conclusion was verified by the detection of transgene-encoded GUS transcripts and endogenous SLG-homologous transcripts by RNA gel blot analysis. Significantly, in anthers, the SLG promoter was active not only sporophytically in the nurse cells of the tapetum, but also in the haploid microspores. Because self-incompatibility systems exhibiting sporophytic control of pollen phenotype are thought to have evolved from systems with gametophytic control, we suggest that sporophytic control was acquired without loss of gametophytic function.

Development of loquat fruit was divided into two phases. The first was growth phase characterized by a growth of seed. The second was maturation phase characterized by decreasing acid content, color development and softening of the pulp tissue. In addition to these phenomena, sugar accumulation and a rapid increase in the fresh weight of the pulp tissue were also observed during maturation. This pattern of maturation is similar to that of fig fruit. The loquat fruit began to evolve ethylene at the beginning of the maturation phase.Sorbitol was a predominant component in the young fruits of loquat. Although sorbitol content increased during the fruit development, its percentage relative to total sugar decreased. Sugar accumulation was accelerated at the beginning of the maturation phase. Sucrose was accumulated faster than any other sugar during this phase, and was a major sugar in the ripe fruit, while sorbitol became a minor component. Ninety percent of the sugar present in the ripe fruit was accumulated within two weeks of maturation. This sugar is thought to be supplied by other parts of the plant.

Mesophyll protoplasts of black mustard and Hakuran were fused by the PEG-high pH ?? igh Ca method. Out of six plants regenerated, one showed hybrid morphology. The hybridity was ascertained by the isozyme pattern of acid phosphatase and chromosome number. This hybrid was estimated to be a trigenomic hexaploid having A. B and C genomes, and showed similar male sterility to Hakuran.

Both biochemical and morphological characters were examined in 85 Japanese cultivars of taro (Colocasia esculenta ) to analyze the phylogenic relationships. Acrylamide gel electrophoresis of the tuber proteins revealed five patterns, designated as E, I, D, T, and A, for the major cultivars. Additional three patterns were found in the minor cultivars. Cluster analysis of taro cultivars based on 40 morphological characters was also performed. The results which were in agreement with those of the above-mentioned biochemical analyses, enabled to identlfy seven groups, i.e. Eguimo, Dodare (Dotare), Hasubaimo, Ishikawa-wase, Kurojiku, Akame, and Tonoimo groups, for the non-fasciculated taro cultivars, while two, Yatsugashira and Shogaimo groups for the fasciculated ones. The Yatsugashira group showed elec-trophoretic patterns common to the non-fasciculated Tonoimo group. Similarly the Shogaimo and Dodare groups exhibited a common electrophoretic pattern. The fasciculated cultivars are, therefore, assumed to be derivecl from the corresponding non-fasciculated cultivars by bud mutation. The Kurojiku group may be at the origin of the Ishikawa-wase group, since these two groups showed a common electrophoretlc pattern. The phylogenic and morphological relationships between the Hasubaimo and Dodare groups were also discussed.

During the coloring of normal puffy cultivars of satsuma mandarin (Citrus unshiu Marc.), the peel (flavedo plus albedo) continued to grow, i.e. increase its fresh weight, even after the pulp growth had terminated. The fruit became puffy when the pulp growth had already ceased but the peel was still growing. This peel growth accompanied the increase in dry weight, and the soluble sugar accounted for almost all of the dry matter increase in the peel. While, the content of alcohol insoluble substance remained unchanged. Protein content and acid phosphatase activity in the peel increased gradually during the coloring.Ethephon enhanced the puffiness to some extent and slightly increased peel fresh and dry weights.During coloring, the peel growth and the increase in sugar content of‘Imamura unshu’, which is known as a non-puffy cultivar, were slower than those of ‘Sugiyama unshu’, a normal puffy cultivar.

The varietal differences in embryogenic ability in anther culture of Chinese cabbage, Brassica campestris ssp. pekinensis, were investigated. In the first experiment, the anthers of B. campestris were incubated in the modified B5 medium (KELLER and ARMSTRONG 1979) at 30°C for 14 days and then maintained at 25°C in the dark. Only a few embryos were ob-served in a limited number of cultivars in this treatment. In contrast, embryos were formed efficiently by the treatment at 35'C for one day. The embryogenic ability from anthers was remarkably different among the cultivars. Among the cultivars of B. campestris, the anthers of 'ASO Ichigo' belonging to the Kenshin group produced embryos most efficiently. The second experiment was conducted to know the embryogenic ability of cultivars in the Kenshin group. Although some varietal differences in the embryogenic ability were observed, one of the cultivars exhibited the highest culture efficiency (expected yield of embryos from 1, 000 anthers cultured) of over 10, 000. Comparing the data of two experiments, the Kenshin group were thought to have a high embryogenic ability in anther culture of Chinese cabbage.

NAD malic enzyme activity was found in the 15 000 g precipitate of citrus leaf and fruit tissues. The enzyme activity in juice vesicle tissue did not change during the fruit growing period, but doubled following ripening. Partially purified enzyme was activated by CoA or FDP. Affinity for malate changed depending on enzyme concentration. The dependency was lost by addition of tricarboxylic acids but not dicarboxylic acids.

Isozymes of GOT and MDH in leaves of 105 citrus biotypes were analyzed using acrylamide gel electrophoresis. At least 3 loci were detected on these two enzymes. From the analysis, Natsumikan (Citrus natsudaidai), Hassaku (C. hassaku) and some other citrus cultivars are considered to be hybrids of pummelo (C.grandis) and mandarin as suggested. Moreover, Iyo (C.iyo), which has been assumed to be a hybrid of sweet orange (C.sinensis) and mandarin, was found to have a genetic effect from pummelo. Sour oranges (C.aurantium) had unique allele A at Got-1. In addition to the sour orange, the same allele was found only in lchang lemon (C.wilsoni), Bergamot (C. bergamia) and 'Hirado' pummelo. While, Tachibana (C.tachibana), Shiikuwasha (C. depressa), and Korai-tachibana (C. nippokoreana), which are reported to be native to Japan and its neighboring areas, had an unique allele A at Got-2. This allele was also found in Hyuganatsu (C.tamurana) and some biotypes originated in Japan, but not found in mandarins originated in mainland China, India, Philippines and other areas. While, Yuzu (C.junos) and its relatives had B at Got-2 and B at Mdh-1.

The plasma concentration of atrial natriuretic polypeptide was measured in eight healthy men during two grades of exercise performed in the supine position on a bicycle ergometer. The plasma concentration of atrial natriuretic polypeptide slightly increased during the first exercise test with 20% of the maximal oxygen uptake and it approximately doubled during the second exercise with 40% of the maximal oxygen uptake (from 15.5 ± 5.5 (mean ± sd) pmol/l to 31.8 ± 10.7 pmol/l). The increase in the plasma level of atrial natriuretic polypeptide in the second exercise was significantly greater than that in the first one. The plasma norepinephrine level and plasma renin activity showed significant increases during the second exercise test. Heart rate and systolic blood pressure also increased in response to the graded exercise. The increase in the plasma concentration of atrial natriuretic polypeptide during exercise was significantly correlated with the increase in heart rate, systolic blood pressure, and the plasma norepinephrine concentration (r = 0.75, r = 0.71 and r = 0.51, respectively). These results indicate that the plasma concentration of atrial natriuretic polypeptide increases in response to the intensity of a workload, and suggest that exercise is a useful test to evaluate the releasing function of atrial natriuretic polypeptide in the heart.

Leaf isozymes of four enzymes in citrus were analyzed using polyacrylamide gel electrophoresis to demonstrate the phylogenic relationship of the cultivars. Two loci for the superoxide dismutase(SOD) (EC1.15.1.1), one locus for the peroxidase (EC 1.11.1.7) and polyphenol oxidase (EC1.10.3.2), respectively were examined. In addition to the two loci of glutamate oxal-acetate transaminase(GOT) (EC2.6.1.1), reported in the former study, a new locus was detected in the present report. These experiments suggest that the mandarin cultivars originated from three genetic sources ; Indian, Chinese, and Japanese ones. Most of the Chinese mandarins including 'Kinokuni' showed identical genotypes, while the 'Ponkan' and 'Dancy tangerine' differed from the Chinese cultivars in their genotypes at the Px locus, and they were assumed to have originated from India as suggested by T. Tanaka. On the other hand, the Japanese mandarins were considered to be genetically affected by the'Chinese mandarins. But some of the Japanese mandarins including 'Yatsushiro' and 'Koji' exhibited genetic effects from Tachibana, the wild type of the mandarin in J.apan. The genotypes of the sweet orange cultivars were homogeneous and similar to those 0L the Chinese mandarins. Sour orange was heterozygous at several loci, and was assumed to be a hybrid between mandarin and pummelo. Among the pummelo cultivars, some heterogeneity was detected at some loci.

Sorbitol-6-phosphate dehydrogenase was found in flesh tissue of mature fruit of the loquat (Eriobotrya japonica Lindl. var. Tanaka). The enzyme was purified about 30-fold from the crude extract of the fruit, and was demonstrated to catalyze sorbitol-6-phosphate + NADP right harpoon over left harpoon glucose-6-phosphate + NADPH. The optimal pH values for sorbitol 6-phosphate oxidation and glucose 6-phosphate reduction were 9.8 and 9.1, respectively.

To study the role of sorbitol-6-phosphate dehydrogenase in sorbitol synthesis in leaves of Rosaceous plants, properties of the enzyme and its presence in several plants in the family was investigated. The activity of the enzyme, which catalyzes an NADP-dependent oxidation of the substrate to glucose-6-phosphate, was detected in leaves of Prunus mume, Prunus persica, Rhaphiolepsis indica, Sorbus aucuparia, Cydonia oblonga, Photinia glabra, Sorbaria kirilowii , and Spiraea thunbergii. The enzyme was purified about 60-fold from leaves of loquat ( Eriobotrya japonica ) using affinity chromatography with Blue Sepharose. Neither mannitol-1-phosphate nor fructose-6-phosphate served as substrate. Molecular weight of the enzyme was calculated to be 65,000 at pH 8.0 by gel filtration. Since sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a peptide of 33,000 daltons, the enzyme was assumed to be a dimer at pH 8.0 K m values for sorbitol-6-phosphate, glucose-6-phosphate, NADP, and NADPH were 2.22 millimolar, 11.6 millimolar, 13.5 micromolar, and 1.61 micromolar, respectively. Equilibrium constant for sorbitol-6-phosphate oxidation was 5.12 × 10 −10 . Optimal pH for sorbitol-6-phosphate oxidation was 9.8. The enzyme showed its maximum activity within a broad pH range between 7 and 9 for glucose-6-phosphate reduction. The enzyme was more effective in the direction of glucose-6-phosphate reduction than in the reverse direction at neutral pH. Thus, it is suggested that the enzyme catalyzes sorbitol synthesis from glucose-6-phosphate during photosynthesis in leaves of Rosaceous plants.

Isolated microspores of Chinese cabbage (Brassica campestris ssp. pekinensis) were incubated in modified NN medium containing 10% sucrose in darkness at 33°C for one day followed by culture at 25°C. After 14 days of culture, microspores developed into embryos ranging from globular to cotyledonary stage. Plants were regenerated after transfer of embryos to medium containing 3% sucrose and no plant growth regulators.

Two RNases in bound forms associated with the microsomal membrane and with the ribosomes or unknown particles in pea root tissue were solubilized by subjecting the membrane to sonic oscillation in the presence of EDTA and KC1 and by treating the particles with EDTA, respectively. The RNases were than purified by DEAE-cellulose and Sephadex G-75 column chromatographies. The elution profiles of RNases from the columns were very similar. No significant differences were observed in their electrophoretic mobilities in polyacrylamide gels, in molecular weight, in activation by inorganic ions, urea or phospholipid micelles or in the dependence of their activities upon pH. The purified RNASES were not different from the bound enzymes as regards activation by inorganic ions and urea and the dependence of the activity upon pH. Triton X-100 stimulated the activity only if RNase was in a bound form associated with the microsomal membrane. We propose that the two RNases may be the same molecular species and differ only in the form of association with intracellular structures.

To investigate ventilatory response to mild hypoxia during non-rapid-eye-movement sleep, we administered approximately 16% O2 (which corresponds to concentrations found in commercial high altitude air craft) to 12 normal subjects by using a Venturi mask, which did not alter the breathing pattern during this study. Under mild hypoxia, inspiratory minute ventilation during sleep showed an initial rapid increase (P less than 0.001) but then declined significantly (P less than 0.001) and stabilized. Stable levels differed among individuals and, compared with those measured before hypoxia, were significantly lower in some subjects, higher in one, and essentially unchanged in the others. The initial rapid increase in minute ventilation after mild hypoxia during sleep correlated with the respective values of hypoxic ventilatory response during the awake state (P less than 0.01), but the final lowered levels did not. We conclude that the ventilatory response after mild hypoxia during sleep is biphasic and hypoxic depression exerts considerable influence on ventilation under mild hypoxia during sleep. So we should take hypoxic depression into consideration to evaluate the response to hypoxia during sleep.

A thornless variant of the trifoliate orange [Poncirus trifoliata (L.) Raf.] was found as a chance seedling. All other characters were indistinguishable from those of normal trifoliate. Genotypes of the variant at loci controlling GOT isozymes were PP,SS, whereas those of the normal trifoliate orange have been reported to be MP,SM. The variant is concluded to arise from spontaneous inbreeding of normal thorny trifoliate orange. The variant showed poor growth.