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1.
Hoshino Atsushi; Abe Yukihide; Saito Norio; Inagaki Yoshishige; Iida Shigeru 《Plant & cell physiology》1997,38(8):970-974
The Japanese morning glory carrying the recessive mutable speckledallele with the dominant speckled-activator bears colorlessflowers with fine and round colored spots distributed over thecorolla whereas the plant without the speckled-activator producespale yellow flowers. Previous chemical analysis has indicatedthat a mutation in the gene for flavanone 3-hydroxylase (F3H)is a likely candidate for the speckled allele. However, theF3HmRNA without sequence alteration accumulates normally inthe pale yellow flowers, indicating that the speckled alleleis neither the F3H gene nor a regulatory gene acting on theF3H gene expression. (Received April 4, 1997; Accepted June 2, 1997) 相似文献
2.
Keisuke Hanaki Tomonori Matsuo Michihiko Nagase 《Biotechnology and bioengineering》1981,23(7):1591-1610
The inhibitory effect of long-chain fatty acids on the anaerobic digestion process was examined in batch experiments using synthetic substrates. The addition of long-chain fatty acids caused the appearance of the appearance of the lag period in the methane production from acetate and in the degradation of both long-chain fatty acids and n-butyrate. Methane production from hydrogen proceeded without lag period although its rate was lowered. Fermentation of glucose was not inhibited. Neutral fat in the whole milk was easily hydrolyzed to long-chain fatty acids, which brought about the inhibition. The addition of calcium chloride reduced the inhibitory effect of long-chain fatty but it did not do so after the culture had been exposed to long-chain fatty acids for more than several hours. The addition of calcium carbonate could not reduce the inhibition because of its insolubility. 相似文献
3.
4.
Sleep and Biological Rhythms - 相似文献
5.
6.
Three O-methyltransferases which catalyze S-adenosyl-L-methionine (SAM)-dependent O-methylation of licodione (LMT), flavone/flavonol (FMT), and caffeic acid (CMT) were separated from the callus culture of Glycyrrhiza echinata, and characteristic differences between their pH optima and Mg2+ requirement for activity were demonstrated. The activity of LMT, which is involved in retrochalcone (echinatin) biosynthesis, but not of FMT or CMT, was found to be stimulated when suspension-cultured G. echinata cells were treated with yeast extract (YE), which causes rapid production of echinatin in the cells. Cycloheximide suppressed both the YE-induced echinatin formation and LMT enhancement. The results indicate a selective induction of retrochalcone pathway in Glycyrrhiza cells in response to stress.Abbreviations SAM
S-adenosyl-L-methionine
- LMT, SAM
licodione 2-O-methyltransferase
- FMT, SAM
flavone/flavonol O-methyltransferase
- CMT, SAM
caffeate 3-O-methyltransferase
- OMT
O-methyltransferase
- CH
cycloheximide
- YE
yeast extract
This paper is Part 47 in the series Studies on Plant Tissue Cultures. For Part 46, see Ayabe S, Iida K, Furuya T (1986) Phytochemistry: in press 相似文献
7.
Hiroaki Nobuhara Keisuke Kuida Makoto Furutani Toshihiko Shiroishi Kazuo Moriwaki Yusuke Yanagi Tomio Tada 《Immunogenetics》1989,30(6):405-413
Southern blots of genomic DNA from 23 strains of laboratory mice and 19 individual wild mice were examined for restriction
fragment length polymorphisms in their loci encoding the T-cell receptors (Tcr): the constant regions of the α, β, and γ chains
(C
α,C
β, andC
γ) and a variable region family of the β chain (V
β8). Only a few polymorphisms were observed for each locus in the laboratory mice after using three restriction enzymes,Bam HI,Eco RI, andHind III. All the laboratory mice examined fall into one of two types for theC
α,C
β andV
β8 loci and one of three types for theC
γ. These types are found in some of the wild mice studied, indicating that they were already present in the founder mice of
laboratory mouse strains. In contrast, theTcr genes are highly polymorphic among wild mice. Analysis of the polymorphisms in these loci suggests that laboratory mice have
inherited their genes not only fromMus musculus domesticus, but also from other subspecies, and much more than previously believed from Asian subspecies. 相似文献
8.
Toshikuni Sasaoka Norio Kaneda Yoshikazu Kurosawa Keisuke Fujita Toshiharu Nagatsu 《Neurochemistry international》1989,15(4):555-565
The chromosomal gene for human phenylethanolamine N-methyltransferase (PNMT; EC 2.1.1.28) was isolated from a human genomic library using a cloned human PNMT cDNA as a probe, and the nucleotide sequence was determined. PNMT is encoded in a single gene which consists of three exons. We observed newly the presence of minor PNMT mRNA (type B) besides the major mRNA (type A) as reported previously (Kaneda et al., J. Biol. Chem. 263, 7672–7677, 1988) by Northern hybridization. Type B mRNA carries an approximately 700 nucleotide-long untranslated region in the 5′ terminus. This suggests that two types of mRNA are produced from a single gene through the use of two alternative promoters. A TATA-like sequence locates 30 base pair upstream from the cap site of type A mRNA. Upstream of the cap site, there are several sequences resembling Spl binding sites and glucocorticoid responsive elements, with the latter also found in the first intron. 相似文献
9.
K Sobue K Kanda I Miyamoto K Iida I Yahara R Hirai A Hiragun 《Experimental cell research》1989,181(1):256-262
With fluorescence and interference reflection microscopy (IRM), we compared the regional distribution of calspectin, its interacting proteins (nonerythroid protein 4.1 and calpactin), alpha-actinin, and vinculin in NRK cells and their avian sarcoma virus (ASV)- or temperature-sensitive (ts) Rous sarcoma virus (RSV)-transformed cells. The localization of these cytoskeletal proteins was determined with the specific antibodies. In NRK cells, alpha-actinin and vinculin were concentrated at adhesion plaques. By contrast, calspectin was distributed throughout the cytoplasm, but not concentrated at adhesion plaques. In ASV- and ts RSV-transformed cells, all three cytoskeletal proteins were concentrated at dot structures representing cellular feet. Nonerythroid protein 4.1 and calpactin were diffusely distributed throughout the cytoplasm of NRK cells and their transformed counterparts. In the case of calpactin, a part of this protein was excluded near regions of the terminal ends of stress fibers. These two proteins did not show the restricted location at the dot structures of transformed cells. From these findings, it is apparent that the accumulation of calspectin into dot structures is a specific event for cell transformation induced by the src protein. 相似文献
10.
A Imai K Iida T Tamaya 《Comparative biochemistry and physiology. B, Comparative biochemistry》1990,97(3):617-621
1. Stimulated inositolphospholipid turnover has been proposed as a signal-transducing mechanism in many cell types. It appears to be initiated by stimulation of hydrolysis of inositolphospholipid by a phospholipase C. 2. In human endometrial fibroblasts, estradiol was observed to cause sequential enhancement of [32P]phosphate incorporation into phosphatidic acid (PA) and phosphatidylinositol (PI), indicating an accelerating effect of estradiol on inositolphospholipid turnover. Specific 32P-radioactivity in the gamma-phosphate of ATP was increased in response to estradiol. Estrone or estriol were without any effects. 3. To investigate possible mechanisms by which estradiol activates a phospholipase C enzyme in the fibroblasts, the plasma membrane fraction isolated from the fibroblasts was exposed to estradiol in the presence of guanosine triphosphate (GTP) to detect inositol trisphosphate (IP3) production. The IP3 production was Ca2+ dependent, a dependency not affected by estradiol. 4. However, ATP decreased the Ca2+ concentration required for IP3 production in a dose-dependent manner; adenosine diphosphate (ADP), cytidine triphosphate (CTP) showed no effects. 5. These findings from cell and cell-free systems might suggest that estradiol stimulates a phospholipase C, as a result of enhancement of intracellular ATP synthesis, but not as a result of a direct effect on the enzyme molecule or direct activation of receptor-phospholipase C unit. 6. This may give us new insight into estrogen-stimulated cellular phenomenon through some mechanisms other than that classically associated with the action of estrogen. 相似文献