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611.
The effects of soil-water salinity on growth and photosynthesis of three coastal dune plants were examined by salt-treatment
in order to clarify the causal relationship between salinity and plant distribution in a dune habitat. Plants were cultivated
hydroponically at three salinity levels: 0, 10 and 100 mM NaCl. With the 100 mM salt treatment,Calystegia soldanella (C3 species) had the highest relative growth rate (RGR) (0.085 g g−1 d−1), followed byCarex kobomugi (C3) (0.066), andIschaemum anthephoroides (C4) (0.060). This order coincides with the distribution pattern of the three species on coastal dunes;Calystegia soldanella is generally distributed in more seaward areas whereasI. anthephoroides occurs further inland. The order of RGR was determined exclusively by leaf area ratio (LAR) among the three species. Due
to its C4 pathway,I. anthephoroides had higher net photosynthetic rate (Pn) and net assimilation rate (NAR) than the two C3 plants at all NaCl concentrations, despite its low RGR. This apparent discrepancy is explainable by differences of LAR among
the three species; LAR ofI. anthephoroides was lowest, and about half that ofCalystegia soldanella. These results suggest that LAR is one of the main determinants of salt tolerance based on RGR, whereas Pn or NAR may not
be significant.
This article is dedicated to Professor Hideo Iwaki, University of Tsukuba, in appreciation of the sincere encouragement he
has given to the authors. 相似文献
612.
Using a panel of rat x mouse somatic cell hybrids and in situ hybridization, we determined the chromosomal location of the rat FOS gene locus. Southern blot analysis assigned this oncogene to rat chromosome 6. In situ hybridization confirmed this finding and mapped the gene more precisely to 6q21----q2. 相似文献
613.
Lymphoblastoid cell lines were established after transformation by Epstein-Barr virus of peripheral lymphocytes from xeroderma pigmentosum (XP) patients and normal donors. These lines expressed B-lymphocyte characteristics. Typical characteristics related to XP of these cell lines were not altered by transformation. Extracts of these cells catalyzed release of uracil (Ura) and 3-methyladenine (3MeAde) from Ura-containing DNA (Ura-DNA) and methylated DNA (Me-DNA), respectively. These two activities, Ura-DNA glycosylase and 3MeAde-DNA glycosylase, differed in heat stability. Extracts released Ura more rapidly and 3MeAde more slowly from a single-stranded DNA than from a double-stranded DNA. On incubation with reconstituted chromatins prepared from Ura-DNA and Me-DNA, respectively, with calf thymus chromosomal protein, cell extracts released all the Ura but about half the 3MeAde residues. The activity levels of these two enzymes of XP cells were similar to those of normal cells. 相似文献
614.
M Shinoda S Nakajin T Oikawa M Shimizu A Kamogawa 《Biochimica et biophysica acta》1979,584(1):116-120
A leukocytosis-promoting substance was purified from a crude bovine parotid gland extract. The purified substance was proved to be a single component by polyacrylamide gel disc electrophoresis. It stimulates an increase of peripheral leukocyte numbers in rabbits. The molecular weight of the physiologically active component was estimated to be 4.5 . 10(4), and the component was found by sodium dodecyl sulfate polyacrylamide gel electrophoresis to be dissociated into two subcomponents. 相似文献
615.
Endothelin stimulates accumulations of cellular atrial natriuretic peptide and its messenger RNA in rat cardiocytes 总被引:5,自引:0,他引:5
Y Fukuda Y Hirata S Taketani T Kojima S Oikawa H Nakazato Y Kobayashi 《Biochemical and biophysical research communications》1989,164(3):1431-1436
The effect of endothelin-1 (ET-1) on secretion and synthesis of rat atrial natriuretic peptide (rANP) as well as its mRNA levels was studied in primary cultures of neonatal rat atrial cardiocytes. ET-1 dose-dependently (10(-10)-10(-7) M) increased media and cellular rANP-like immunoreactivity as well as its cytoplasmic mRNA levels in rat cardiocytes during 24 hrs incubation. These results suggest that ET-1 directly stimulates expression of the rANP gene in cardiocytes, thereby leading to enhanced synthesis and secretion of rANP. 相似文献
616.
A novel acid phosphatase excreted by Penicillium funiculosum that hydrolyzes both phosphodiesters and phosphomonoesters with aryl leaving groups 总被引:1,自引:0,他引:1
An acid phosphatase has been purified from the culture broth of Penicillium funiculosum by procedures including SP-Sephadex column chromatography and Sephacryl S-200 gel filtration. The phosphatase appears to be a 76 kDa heterodimer composed of 51 and 26 kDa subunits on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme hydrolyzes both phosphodiesters and phosphomonoesters, but only those with aryl leaving groups. At the early phase of degradation of bis-p-nitrophenyl phosphate by the enzyme, inorganic phosphate and the intermediary product, p-nitrophenyl phosphate, are liberated at approximately the same rate. This indicates that the intermediary phosphomonoester produced on the enzyme is further hydrolyzed in situ or dissociates into the medium at approximately the same probability. 相似文献