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51.
We have prepared polyclonal antibodies againstXenopus20S proteasomes. The antibodies cross-react with several proteins that are common to 20S and 26S proteasomes and with at least two proteins that are unique to 26S proteasomes. The antibodies were used to analyze changes in the components of proteasomes during oocyte maturation and early development ofXenopus laevis.A novel protein with a molecular weight of 48 kDa, p48, was clearly detected in immature oocytes, but was found at very low levels in mature oocytes and ovulated eggs. p48 was reduced to low levels during oocyte maturation, after maturation-promoting factor was activated. The amount of p48 in eggs remained low during early embryonic development, but increased again after the midblastula transition. These results show that at least one component of 26S proteasomes changes during oocyte maturation and early development and suggest that alterations in proteasome function may be important for the regulation of developmental events, such as the rapid cell cycles, of the early embryo.  相似文献   
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Brassica self-incompatibility (SI) is controlled by SLG and SRK expressed in the stigma and by SP11/SCR expressed in the anther. We determined the sequences of the S domains of 36 SRK alleles, 13 SLG alleles, and 14 SP11 alleles from Brassica oleracea and B. rapa. We found three S haplotypes lacking SLG genes in B. rapa, confirming that SLG is not essential for the SI recognition system. Together with reported sequences, the nucleotide diversities per synonymous and nonsynonymous site (pi(S) and pi(N)) at the SRK, SLG, and SP11 loci within B. oleracea were computed. The ratios of pi(N):pi(S) for SP11 and the hypervariable region of SRK were significantly >1, suggesting operation of diversifying selection to maintain the diversity of these regions. In the phylogenetic trees of 12 SP11 sequences and their linked SRK alleles, the tree topology was not significantly different between SP11 and SRK, suggesting a tight linkage of male and female SI determinants during the evolutionary course of these haplotypes. Genetic exchanges between SLG and SRK seem to be frequent; three such recent exchanges were detected. The evolution of S haplotypes and the effect of gene conversion on self-incompatibility are discussed.  相似文献   
53.
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   
54.
Rhodes grass (Chloris gayana) is one of the most important warm-season forage grasses. It is cultivated in tropical and subtropical parts of the world and is mostly used for grazing and hay production. We have established a particle-bombardment transformation protocol for rhodes grass using multiple-shoot clumps (MSCs) as the target tissue. A vector pAHC25 containing a herbicide-resistance gene (bar) together with the beta-glucuronidase (GUS) gene was used in transformation experiments. The most efficient recovery of bialaphos-resistant tissue was achieved when the bombarded MSCs were first cultured for 15 d on bialaphos-free medium before being subjected to selection pressure. The resistant tissues regenerated transgenic plants that displayed GUS gene expression. Under optimized conditions, 251 target pieces yielded 46 transgenic plants from 4 independent transgenic lines.  相似文献   
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Two cDNA forms were characterized for a human dnaJ homologue, HSJ2. Nucleotide sequencing showed that the gene product HSJ2 was longer than previously reported, extending its homology to other human DnaJ paralogues, and that the two cDNAs encoded two proteins as a result of alternative splicing. The products were 326 amino acids (designated as HSJ2a) and 241 amino acids (HSJ2b) in length, sharing the N-terminal 231 amino acids including the DnaJ homology region. When fused to green fluorescent protein and expressed in HeLa cells, HSJ2a was found to be localized to the nucleus, indicating that HSJ2a is a nuclear co-chaperone. HSJ2b, however, was observed throughout the cell, consistent with the elimination of a putative nuclear localization signal sequence as a result of the alternative splicing.  相似文献   
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In this study, we immunized Gb3/CD77 synthase gene (A4galt) knockout (KO) mice with glycosphingolipids (GSLs) extracted from 3 renal cell cancer (RCC) cell lines to raise monoclonal antibodies (mAbs) reactive with globo-series GSLs specifically expressed in RCCs. Although a number of mAbs reactive with globo-series GSLs were generated, they reacted with both RCC cell lines and normal kidney cells. When we analyzed recognized antigens by mAbs that were specifically reactive with RCC, but not with normal kidney cells at least on the cell surface, many of them turned out to be reactive with sulfoglycolipids. Eight out of 11 RCC-specific mAbs were reactive with SM2 alone, and the other 3 mAbs were more broadly reactive with sulfated glycolipids, i.e. SM3 and SM4 as well as SM2. In the immunohistochemistry, these anti-sulfoglycolipids mAbs showed RCC-specific reaction, with no or minimal reaction with adjacent normal tissues. Thus, immunization of A4galt KO mice with RCC-derived GSLs resulted in the generation of anti sulfated GSL mAbs, and these mAbs may be applicable for the therapeutics for RCC patients.  相似文献   
59.
Domesticated adult dogs with antibody titer classified as below 'high' to one or more of canine distemper virus (CDV), canine parvovirus type-2 (CPV-2) and canine adenovirus type-1 (CAdV-1) were then given an additional inoculation, and the effectiveness of this booster evaluated 2 months later. Consequently, CDV and CAdV-1 antibody titer experienced a significant increase, but the same effect was not observed in the antibody titer of CPV-2. These findings suggest that with additional inoculation, a booster effect may be expected in increasing antibody titers for CDV and CAdV-1, but it is unlikely to give an increase in CPV-2 antibody titer.  相似文献   
60.
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