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101.
A complete sequence of the pGA1611 binary vector   总被引:1,自引:0,他引:1  
We report the nucleotide sequence of the binary vector pGA1611, which is used for the transformation of foreign DNA into rice. This vector is 13,476 bp long. The 5577- bp T- DNA region consists of a 1987- bp ubiquitine promoter region, 45 bp for the multiple cloning site, a 253- bpnos terminator region, and the 2045- bpCaMV35S- hph- T7 chimaeric gene. The vector backbone (7004 bp) carriesoriT,traJ,trfA,tetA,tetR, andoriV. An 892- bp RB region and the 489- bp LB region are also present The T- DNA possesses 15 unique sites, six of which are at the multiple cloning site. This information will be valuable for cloning foreign DNA and modifying the vector.  相似文献   
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Recombinant tumstatin was expressed in stably transformed Drosophila melanogaster S2 cells and secreted into the medium with a molecular size of 29 kDa. Recombinant endostatin was also purified to homogeneity using a simple one-step Ni2+ affinity fractionation. Purified recombinant tumstatin inhibited endothelial cell proliferation in a dose-dependent manner. The concentration at half-maximum inhibition for recombinant tumstatin was approx. 0.7 g ml–1. A maximum production of 4.6 g recombinant tumstatin (107 cells)–1 was obtained in a T-flask culture of S2 cells, 7 d after induction with 0.5 mM CuSO4.  相似文献   
105.
Extracts of Phellinus linteus (EPB), grown on germinated brown rice, protected rats from liver injury induced by carbon tetrachloride (CCl4). Peroxidation products in the liver were decreased to 10% by EPB. Catalase and superoxide dismutase activities were significantly decreased to 55% and 39% by CCl4 administration, but EPB blocked this effect, resulting in enzyme activities at control levels. Expression of cytochromeP450 2E1 (CYP2E1) protein was significantly decreased to 88% in CCl4-treated rats but remained at control levels when EPB was also administered. EPB did not affect the altered fatty acid composition induced by CCl4. The hepatoprotective effect of EPB may be mediated by EPB's prevention of CCl4-induced CYP2E1 degradation.  相似文献   
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We studied plasma leptin levels in six people with high-lesion spinal cord injury [SCI; body mass index (BMI) 25.9 +/- 1.5 kg/m(2), age 37 +/- 3.0 yr] and six able-bodied (AB) controls (BMI 29.1 +/- 1.9 kg/m(2), age 35 +/- 3.5 yr) before and after 12, 24, and 36 h of fasting. The plasma leptin levels significantly decreased during 36 h fasting by 48.8 +/- 4.5% (pre: 11.3 +/- 2.3, post: 6.2 +/- 1.5 ng/ml) and 38.6 +/- 7.9% (pre: 7.6 +/- 5.0, post: 4.2 +/- 1.0 ng/ml) in SCI and AB, respectively. Plasma leptin started to decrease at 24 h of fasting in the SCI group, whereas plasma leptin started to decrease at 12 h of fasting in the AB group. The current study demonstrated that plasma leptin decreased with fasting in both SCI and AB groups, with the leptin decrease being delayed in the SCI group. The delayed leptin response to fasting in the SCI group may be because of increased fat mass (%body fat, SCI: 33.8 +/- 3.0, AB: 24.1 +/- 2.9) and sympathetic nervous system dysfunction.  相似文献   
108.
The secretory granules of neuroendocrine cells which contain large amounts of Ca(2+) and chromogranins have been demonstrated to release Ca(2+) in response to inositol 1,4,5-trisphosphate (IP(3)). Moreover, chromogranin A (CGA) has been shown to interact with several secretory granule membrane proteins, including the IP(3) receptor (IP(3)R). To determine whether the IP(3)Rs interact directly with chromogranins A and B (CGB), two major proteins of the secretory granules, we have used purified IP(3)R from bovine cerebellum in the interaction study with CGA and CGB, and have shown that chromogranins A and B directly interact with the IP(3)R at the intravesicular pH 5.5. Immunogold cytochemical study using the IP(3)R and CGA antibodies indicated that IP(3)R-labeled gold particles were localized in the periphery of the secretory granules, indicating the presence of the IP(3)Rs on the secretory granule membrane. To determine whether the IP(3)R and chromogranins A and B are physically linked in the cells, bovine type 1 IP(3)R (IP(3)R-1) and CGA or CGB are co-transfected into COS-7 cells and co-immunoprecipitation was carried out. Immunoprecipitation of the cell extracts demonstrated the presence of CGA-IP(3)R-1 and CGB-IP(3)R-1 complexes, respectively, indicating the complex formation between the IP(3)R and chromogranins A and B in native state.  相似文献   
109.
The domestic pig originates from the Eurasian wild boar (Sus scrofa). We have sequenced mitochondrial DNA and nuclear genes from wild and domestic pigs from Asia and Europe. Clear evidence was obtained for domestication to have occurred independently from wild boar subspecies in Europe and Asia. The time since divergence of the ancestral forms was estimated at approximately 500,000 years, well before domestication approximately 9,000 years ago. Historical records indicate that Asian pigs were introduced into Europe during the 18th and early 19th centuries. We found molecular evidence for this introgression and the data indicated a hybrid origin of some major "European" pig breeds. The study is an advance in pig genetics and has important implications for the maintenance and utilization of genetic diversity in this livestock species.  相似文献   
110.
Protoporphyrinogen oxidase (Protox), the penultimate step enzyme of the branch point for the biosynthetic pathway of Chl and hemes, is the target site of action of diphenyl ether (DPE) herbicides. However, Bacillus subtilis Protox is known to be resistant to the herbicides. In order to develop the herbicide-resistant plants, the transgenic rice plants were generated via expression of B. subtilis Protox gene under ubiquitin promoter targeted to the cytoplasm or to the plastid using Agrobacterium-mediated gene transformation. The integration and expression of the transgene were investigated at T0 generation by DNA and RNA blots. Most transgenic rice plants revealed one copy transgene insertion into the rice genome, but some with 3 copies. The expression levels of B. subtilis Protox mRNA appeared to correlate with the copy number. Furthermore, the plastidal transgenic lines exhibited much higher expression of the Protox mRNA than the cytoplasmic transgenic lines. The transgenic plants expressing the B. subtilis Protox gene at T0 generation were found to be resistant to oxyfluorfen when judged by cellular damage with respect to cellular leakage, Chl loss, and lipid peroxidation. The transgenic rice plants targeted to the plastid exhibited higher resistance to the herbicide than the transgenic plants targeted to the cytoplasm. In addition, possible resistance mechanisms in the transgenic plants to DPE herbicides are discussed.  相似文献   
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