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1.
Binding sites of HeLa cell nuclear proteins on the upstream region of adenovirus type 5 E1A gene. 总被引:6,自引:3,他引:3
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Twenty one binding sites of HeLa cell nuclear proteins were identified on the upstream region of adenovirus type 5 E1A gene using DNase I footprint assay. The proximal promoter region contained five binding sites that overlapped the cap site, TATA box, TATA-like sequence, CCAAT box, and -100 region relative to the E1A cap site(+1). The -190 region was a potential site for octamer-motif binding proteins, such as NFIII and OBP100. An upstream copy of the E1A enhancer element 1 was the site for a factor (E1A-F) with the binding specificity of XGGAYGT (X = A, C; Y = A, T). E1A-F factor also bound to three other sites, one of which coincided with the distal E1A enhancer element. The distal element also contained a potential site for ATF factor. The adenovirus minimal origin of DNA replication competed for DNA-protein complex formation on the CCAAT and TATA box region and the -190 region, suggesting that these regions interacted with a common or related factor. 相似文献
2.
A hybrid gene has been constructed consisting of coding sequence for the membrane domain of the endoplasmic reticulum protein 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase linked to the coding sequence for the soluble enzyme Escherichia coli beta-galactosidase. Expression of the hybrid gene in transfected Chinese hamster ovary cells results in the production of a fusion protein (HMGal) which is localized in the endoplasmic reticulum. The fusion protein contains the high-mannose oligosaccharides characteristic of HMG-CoA reductase. Importantly the beta-galactosidase activity of HMGal decreases when low density lipoprotein is added to the culture media. Therefore, the membrane domain of HMG-CoA reductase is sufficient to determine both correct intracellular localization and sterol-regulation of degradation. Mutant fusion proteins which lack 64, 85, or 98 amino acid residues from within the membrane domain of HMG-CoA reductase are found to be localized in the endoplasmic reticulum and to retain beta-galactosidase activity. However, sterol-regulation of degradation is abolished. 相似文献
3.
K Inada S Endo K Takahashi M Suzuki T Narita T Yoshida H Suda T Komuro M Yoshida 《Microbiology and immunology》1991,35(4):303-314
We established a new method of plasma treatment for the removal of interfering factors in the plasma to allow detection of endotoxin by limulus test. The limulus test used was an endotoxin-specific chromogenic test, the Endospecy test. Perchloric acid (PCA) treatment and centrifugation (PCA method) is usually used to remove interfering factors from plasma, with the precipitate being discarded and the supernatant used to detect endotoxin. As the solubilized precipitates of endotoxin-spiked plasma and some patient plasma were found to contain the Endospecy activity, we have devised a new method assaying endotoxin in both the supernatant and precipitate. This study confirmed that the solubilized precipitate of endotoxin-spiked plasma had Endospecy activity and found that the precipitate had other endotoxin activities, such as lethality in galactosamine-sensitized mice and pyrogenicity in rabbits. We also confirmed that interfering factors were completely removed from plasma samples by this new method. The endotoxin level after the new PCA method was found to be about 8 times higher than that determined after PCA treatment and the new PCA method surpasses the conventional PCA method with regard to the positive rate of endotoxin contents in clinical samples. These results indicate that the new PCA method is superior to the PCA method as a plasma pretreatment method for limulus test. 相似文献
4.
K Kubota N Narita K Ohkubo S Shibanai K Nagae M Kubota N Odagiri T Kawamoto 《Acta anatomica》1988,133(3):200-208
In order to give a neuroanatomical evidence to the mechanism of shifting from sucking to biting, we investigated in prenatal, newborn and postnatal mice whether there is a time difference in the neurogenesis of the neurons relative to sucking and biting or in the histogenesis of their peripheral effector organs by the HRP labeling technique and electron microscopy. The results obtained are as follows. (1) At birth the facial motoneurons exceed the trigeminal motoneurons in cell area and development. (2) After birth, the trigeminal motoneurons grow rapidly and outstrip the growth of the facial motoneurons at the age of 6 days. (3) Thereafter, the cell area of both neuron types continues to increase gradually. (4) The initial sign of the alpha motor end plates is found in the orbicularis oris muscle innervated by the facial nerve in 17-day-old fetuses, while that of the trigeminal nerve is delayed in the masseter muscle of 18-day-old fetuses. (5) The initial sign of the muscle spindle appears with the sensory terminals in the masseter muscle of 17-day-old fetuses and the fundamental structure of the muscle spindle is formed in 4-day-old youngs. (6) Myelination of the facial nerve begins in 3-day-old youngs, while that of the trigeminal nerve becomes apparent in 4- or 5-day-old youngs. From these bases, it is obvious that the facial nerve elements related to sucking are firstly developed at birth and that the differentiation of the trigeminal nerve elements related to biting is rapidly accelerated after birth. 相似文献
5.
This paper describes usefulness of the ultrasonographical device (USD) for the diagnosis of pregnancy and the observation of fetal growth in the squirrel monkeys (Saimiri sciureus) conceived under group breeding conditions. Pregnancy was diagnosed on the basis of the detection of gestational sac (GS) in the uterus. The GS was first detected 127 +/- 10 days before delivery. The heart beat of embryo was detected around 114 days before delivery. It was able to judge conditions of fetal growth by measuring the size of GS and the biparietal diameter. No difference in uterine size between nonpregnant and pregnant animals was observed 135 days before delivery. 相似文献
6.
An enzyme hydrolyzing succinyl trialanine-4-nitroanilide was extracted from human kidney homogenate and purified by means of gel filtration on Sepharose CL-4B, anion-exchange chromatography on DEAE-Sepharose CL-6B and affinity chromatography on carbobenzoxy-L-Ala-L-Ala-D-Ala-polylysine-agarose. The purified enzyme consists of a single peptide, and its molecular weight was estimated to be about 125 000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme cleaved the substrate at the bond between succinyl dialanine and alanine-4-nitroanilide and showed a Km value of 2.1 mM at the optimal pH of 8.0. The activity was increased by Ca2+ and Mg2+, but was inhibited by phosphoramidon and ethylenediaminetetraacetic acid. The enzyme cleaved the oxydized insulin B chain, angiotensinogen tetradecapeptide, angiotensin I, angiotensin II, angiotensin III, [Sar1,Ala8]-angiotensin II, bradykinin, des-Pro2-bradykinin, Leu5-enkephalin, Met 5-enkephalin, [D-Ala2,Met5]-enkephalinamide and [D-Ala2-Met5]-enkephalin, but did not cleave [D-Ala2,D-Leu5]-enkephalin. The bonds on the amino side of the hydrophobic amino acids of the peptides were cleaved by the enzyme. 相似文献
7.
A sensitive method for quantitative analysis of phospholipid molecular species by high-performance liquid chromatography 总被引:9,自引:0,他引:9
A simple and sensitive method was developed for quantitative analysis of phospholipid molecular species. Diacylglycerols were prepared from phospholipids by phospholipase C treatment and converted to the corresponding dinitrobenzoyl derivatives, which could be sensitively detected at 254 nm. The derivatives of 21 molecular species were resolved by high-performance liquid chromatography with an octadecylsilyl reversed-phase column. All the derivatives had the same peak area per mol, and peak areas were proportional to the amounts of the derivatives. Quantification was carried out at the picomole level. 相似文献
8.
I. Nakasono M. Iwasaki M. Ogata T. Yoshitake K. Narita S. Kubo H. Suyama Y. Tanoue 《Human genetics》1985,70(1):84-85
Summary A new single band variant (Gc Ar) or the Gc subtypes not identical with the known Gc variants has been detected in the plasma of a healthy blood donor by isoelectric focusing. Using this technique the variant is represented by a single band which has a similar isoelectric point to the Gc 1C2 anodal band. It is well known that the single band Gc phenotypes remain unaltered after neuraminidase treatment. Nevertheless, the new single band variant (Gc Ar) is altered after neuraminidase treatment as is Gc 2A3. After neuraminidase treatment, the Gc Ar band is affected and moved to the nearby position of the Gc 2 band. Investigation of the proband's family shows that the variant occurs combined with the common alleles Gc 1F, Gc 1S and that it has an autosomal dominant inheritance. 相似文献
9.
Sadaaki Iwanaga Takashi Morita Toshiyuki Miyata Takanori Nakamura Jun Aketagawa 《Journal of Protein Chemistry》1986,5(4):255-268
A hemocyte lysate from horseshoe crab produced a gel, when exposed to Gram-negative bacterial endotoxins. This gelation reaction of the lysate, so-called Limulus test, has been widely employed as a simple and very sensitive assay method for endotoxins. Recent biochemical studies on the principle of Limulus test indicate that the hemocytes contain several serine protease zymogens, which constitute a coagulation cascade triggered by endotoxins, and that there is a (1 3)--d-glucan-mediated coagulation pathway which also results in the formation of gel. Up to now, six protein components, designated coagulogen, proclotting enzyme, factor B, factor C, factor G and anti-LPS factor, all of which are closely associated with the endotoxin-mediated coagulation pathway, have been purified and biochemically characterized. Among these components, the complete amino acid sequences of coagulogens isolated from one American and three Asian species of horseshoe crabs have been established. Moreover, the reconstitution experiment using the isolated clotting factors, C, B, proclotting enzyme and coagulogen in the presence of endotoxin, leads to the formation of coagulin get. Based on these results, we propose here a mechanism for the Limulus coagulation cascade. 相似文献
10.
M Narita S Inui M Kobayashi A Fukusho 《National Institute of Animal Health quarterly》1983,23(3):105-107
After trypsin digestion of buffered formalin-fixed, paraffin-embedded brain section, immunofluorescent indication of Aujeszky's disease virus antigen was successful in experimentally infected cow and goat. This result was comparable to those obtained with light and electron microscopic examinations. This method will be diagnostically useful where fresh-frozen tissue is not available. 相似文献