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1.
Complete Nucleotide Sequence of the Mouse Lactate Dehydrogenase-a Functional Gene: Comparison of the Exon-Intron Organization of Dehydrogenase Genes 总被引:7,自引:0,他引:7 下载免费PDF全文
The complete sequence of 12,851 nucleotides of the mouse lactate dehydrogenase-A (LDH-A) gene has been determined. It includes eight exons, seven introns, promoter and regulatory regions. The B1 repetitive elements present in intron III and VI are oriented in opposite orientation, and they share 72% sequence homology. The exon-intron organization of mouse LDH-A gene is compared with the organizations of other dehydrogenase genes, and the molecular evolution of the nicotinamide adenine dinucleotide binding domains is discussed. 相似文献
2.
Dr. Takashi Yashiro Motonaka Arai Eiko Miyashita Kayoko Yamashita Takuro Suzuki 《Cell and tissue research》1988,251(2):249-255
Summary Snell dwarf mice display remarkable retardation of growth after birth and are known to lack prolactin (PRL), thyroid stimulating hormone (TSH) and growth hormone (GH). The aim of this study was to determine the reason for these hormonal deficiencies. We examined the fine structure of the gland and its immunohistochemical staining pattern with respect to antisera raised against PRL, TSH, GH, adrenocorticotrophic hormone (ACTH) and luteinizing hormone (LH). The gland of control mice reacted immunohistochemically against all antisera used, whereas only ACTH-producing cells (ACTH cells) and LH-producing cells (LH cells) were distinguished in the dwarf mice. ACTH cells in dwarf mice varied in cell shape, although they were similar in size to those of controls. The distribution of secretory granules in the cytoplasm varied from cell to cell. LH cells in the dwarf mice showed immature features, having poorly developed rough endoplasmic reticulum and Golgi apparatus. The cells were about half the size of controls, and secretory granules were smaller. In dwarf mice, non-granulated cells were encountered in addition to granulated ACTH and LH cells. Some of them formed small clusters, characteristic cell junctions being found between the cells; they thus appeared to be follicular cells. The above results suggest that hormone deficiency in Snell dwarf mice is a result of a defect in the hormoneproducing cells in the gland. 相似文献
3.
Masato Maekawa Kayoko Sudo Masato Kitajima Yukio Matsuura Steven S.-L. Li Takashi Kanno 《Human genetics》1993,92(2):163-168
In northwest European countries maternal age is increasing. This will lead to an increase of the prevalence of Down syndrome conceptuses. Meanwhile, the increased use of prenatal cytogenetic diagnosis (PCD) will lead to a decrease in the prevalence of Down syndrome among livebirths. We were interested to know what the result of these two opposite developments would be in the near future, and we describe here a model to quantify these processes and the resulting livebirth prevalence of Down syndrome. The model is demonstrated for The Netherlands from 1992 to 2001. The predicted livebirth prevalence for The Netherlands in 1992 is 1.36 per 1000. Demographic factors will cause an increase to 1.76 per 1000 in 2001 with present indications for PCD and a utilization ratio of 50%. An increase of the utilization ratio to 90% in 2001 will lead to a prevalence of 1.22 per 1000, a little less than the present prevalence. Alternative screening programs, including maternal serum screening, could lead to a further decrease of the livebirth prevalence. The model described here can be used for evaluation of the consequences of alternative forms of Down syndrome screening. 相似文献
4.
Ohta Hiroyuki; Shimojima Mie; Ookata Kayoko; Masuda Tatsuru; Shioi Yuzo; Takamiya Ken-ichiro 《Plant & cell physiology》1995,36(6):1115-1120
Changes in the activity of UDP-galactose:diacylglycerol galactosyltransferase(UDGT), a key enzyme in galactolipid biosynthesis, during germinationwere investigated in cucumber (Cucumis sativus L. cv. Aonagajibai)seedlings. After germination, UDGT activity increased duringgrowth in darkness for 4 days, reaching 10 times the activityin ungerminated seeds. Illumination of 4-day-old dark-grownseedlings strongly stimulated the activity. By contrast, inseedlings grown continuously in darkness, the increase in UDGTactivity ceased after 4 days and the activity remained constantthereafter. A similar increase in the specific activity of UDGTwas observed i n the envelope fraction from seedlings, indicatingthat the increase in the enzymatic activity preceded synthesisof other proteins in the envelope membrane. Coincident withthe change in the enzymatic activity, here was an increase inlevels of monogalactosyl diacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), two major constituents of chloroplastmembrane lipids, in the germinated seedlings. Cycloheximideinhibited the light-mediated increase in the enzymatic activityby illumination of 4-day-old dark-grown seedlings, and, as aconsequence, it inhibited the accumulation of MGDG and DGDG.It was clear, therefore, that protein synthesis was necessaryduring this activation. Addition of a cytokinin, benzyladenine(BA), stimulated the increase in the UDGT activity. The increasein the UDGT activity caused by BA was accompanied by the accumulationof galactolipids, as in the case of the activation by light.These results suggest that activation of the final reactionin the synthesis of MGDG, which is catalyzed by the galactosyl-transferase,contributes to the accumulation of galactolipids during thedevelopment of the chloroplast membrane. (Received December 3, 1994; Accepted July 3, 1995) 相似文献
5.
Pui-Wah Lau Cynthia Hung Kayoko Minakata Elias Schwartz Toshio Asakura 《生物化学与生物物理学报:生物膜》1979,552(3):499-508
A maleimide spin label (N-(1-oxyl-2,2,5,5-tetramethylpyrrolidinyl)-maleimide) was reacted with oxyhemoglobin-free cell stromata of normal and sickle cells. The EPR spectrum of spin-labeled red cell membranes showed that the spin labels are attached to at least two different binding sites. There was a major signal, A, which characterized a strongly immobilized environment and a minor signal, B, which characterized a weakly immobilized environment. Quantitative EPR measurements using equal amounts of Hb AA and Hb SS red blood cells demonstrated that Hb SS red cell membranes had an approximately four times higher EPR signal intensity than Hb AA red cell membranes ((7.98 ± 1.14) · 105 and (2.2 ± 1.2) · 105 spin labels/cell, respectively). Moreover, the ratio of signal intensities A and B are different in these cells. Comparative spectrophotometric studies of membrane-associated denatured hemoglobins of Hb AA and Hb SS red cell membranes suggested that the EPR signal A is derived from spin labels attached to membrane-associated denatured hemoglobin, while signal B is mainly from spin labels attached to membrane-associated denatured hemoglobin, while signal B is mainly from spin labels attached to membranes. The combination of EPR spectrum of Hb AA membranes pretreated with N-ethyl-maleimide and that of spin-labeled precipitated hemoglobin further strengthened this conclusion. 相似文献
6.
When pheromone-pretreated cells of an inducible a strain of Saccharomyces cerevisiae carrying the inducible gene saa1 were incubated in a growth medium at 28°C, induction of sexual agglutinability began after a 10 min lag period. If the cells were incubated at 38°C during the lag period, no induction occurred even after incubation at 28°C. Contrary to this, if the cells were incubated at 28°C during the lag period, almost complete induction occurred, even after transfer to 38°C. Temperature shift experiments revealed that 5 min incubation at 28°C was necessary for the initiation of the temperature-sensitive period and further 5 min incubation for the completion of the period. The temperature-sensitive period was sensitive to phenylmethylsulfonyl fluoride.Non-common abbreviations PBS
10-2 M phosphate buffer solution, pH 5.5
- PMSF
phenylmethylsulfonyl fluoride 相似文献
7.
8.
Reaction of β-maltotriose hendecaacetate with phosphorus pentachloride gave 2′,2″,3,3′,3″,4″,6,6′,6″,-nona-O-acetyl-(2)-O-trichloroacetyl-β-maltotriosyl chloride (2) which was isomerized into the corresponding α anomer (8). Selective ammonolysis of 2 and 8 afforded the 2-hydroxy derivatives 3 and 9, respectively; 3 was isomerized into the α anomer 9. Methanolysis of 2 and 3 in the presence of pyridine and silver nitrate and subsequent deacetylation gave methyl α-maltotrioside. Likewise, methanolysis and O-deacetylation of 9 gave methyl β-maltotrioside which was identical with the compound prepared by the Koenigs—Knorr reaction of 2,2′,2″,3,3′,3″,4″,6,6′,6″-deca-O-acetyl-α-maltotriosyl bromide (12) with methanol followed by O-deacetylation. Several substituted phenyl β-glycosides of maltotriose were also obtained by condensation of phenols with 12 in an alkaline medium. Alkaline degradation of the o-chlorophenyl β-glycoside decaacetate readily gave a high yield of 1,6-anhydro-β-maltotriose. 相似文献
9.
10.
Ishibashi S Iwakiri R Shimoda R Ootani H Kawasaki S Tadano J Kikkawa A Ootani A Oda K Fujise T Yoshida T Tsunada S Sakata H Fujimoto K 《Helicobacter》2002,7(4):245-249
Background. Phospholipids concentration in the gastric mucosa decreased in patients with Helicobacter pylori infection. The aim of this study is to examine the effects of eradication of H. pylori on decreasing the phospholipids concentration in the gastric mucosa in patients with gastric or duodenal ulcer. Materials and Methods. Phospholipids (phosphatidylcholine, phosphatidylethanolamine, and sphingonomyeline) were measured in biopsy specimens from the antrum and corpus using thin‐layer chromatography. In H. pylori positive patients with gastric ulcer (n = 26) and duodenal ulcer (n = 13), and H. pylori negative controls (n = 20), the biopsy specimens were obtained before and 3 months after eradication. Eradication was performed using lansoprazole, amoxycillin, and clarithromycin. Results. Compared with the H. pylori negative control group, the concentrations of phosphatidylcholine and phosphatidylethanolamine decreased significantly in the gastric ulcer group in both antrum and corpus mucosa, and in the duodenal ulcer group in antrum mucosa. This decrease returned to the control level after eradication. Conclusions. This study demonstrates that the eradication of H. pylori in patients with peptic ulcer normalized the decrease of phosphatidylcholine and phosphatidylethanolamine in the gastric mucosa. 相似文献