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11.
Very low polymorphism in the germplasm typically used by breeding programs poses a significant bottleneck with regards to molecular breeding and the exploitation of breeding materials for quantitative trait analyses. California rice cultivars, derived from a very small base of temperate japonica germplasm and having a relatively brief breeding history, are a good example. In this study, we employed a reduced representation sequencing approach called Restriction Enzyme Site Comparative Analysis (RESCAN) to simultaneously identify and genotype single nucleotide polymorphisms (SNPs) in forty-five rice cultivars representing the majority of the 100 year-old breeding history in California. Over 20,000 putative SNPs were detected relative to the Nipponbare reference genome which enabled the identification and analysis of inheritance of pedigree haplotypes. Haplotype blocks distinguishing modern California cultivars from each other and from the ancestral short grain temperate japonica cultivars were easily identified. Reduced representation sequencing methods such as RESCAN are a valuable alternative to SNP chip genotyping and low coverage whole genome sequencing. 相似文献
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Using the catechol dehydrogenase gene as a reporter, we isolated random mutations in the plJ101 korB gene operator/promoter (OP) region that affect korB expression and regulation. We mapped these mutations to inverted repeat sequences within the promoter and studied their effects on binding of the KorB repressor protein to the OP, on expression of the korB gene, and on plasmid transmission during mating. Additionally, we investigated the biological effects of KorB binding to a locus (sti, for st rong I ncompatibility) adjacent to the korB OP and implicated in plJ101 replication. Our results identify sites that influence the synthesis and autoregulation of KorB; they also show that interaction of KorB with sti affects repression of korB and transmission of plasmids to spores of recipients. 相似文献
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Yoko Yamauchi Hikari Kimoto Xianyu Yang Sergey Filkin Yuri Utkin Tai Kubo 《Bioscience, biotechnology, and biochemistry》2016,80(1):158-161
Three-finger toxins (3FTxs) are one of the major components in snake venoms. In this study, we isolated a cDNA encoding a short-chain 3FTx, Pr-SNTX, from Pseudechis rossignolii. The amino acid sequence of Pr-SNTX is nearly identical to that of its ortholog in Pseudechis australis. Pr-SNTX protein inhibited muscle-type (α2βδε), but not neuronal α7 nicotinic acetylcholine receptor (nAChR) activity. 相似文献
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Severe adverse reactions to propylthiouracil occur in 1-5% of patients. Three major side effects, namely agranulocytosis, hepatotoxicity and drug-induced hypersensitivity, have been described though these syndromes are not distinct entities and there can be overlaps in the clinical manifestations. The drug-induced hypersensitivity may be an immune-mediated reaction with multiorgan involvement in which a combination of polyarthritis, cutaneous vasculitis and fever is common. We report a patient with propylthiouracil-induced hypersensitivity with an unusual combination of high spiking fever, migratory polyarthritis, reversible sensorineural deafness, normochromic normocytic anaemia, leucocytosis and hepatotoxicity associated with polyclonal activation of multiple autoantibodies. This case illustrates the highly variable clinical manifestations of the syndrome. The prompt recovery upon withdrawal of the drug indicates the importance of early diagnosis. 相似文献
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Y Y Tai J Ninomiya-Tsuji K Furuoku N Ogawa S Ishibashi K Shiroki K Segawa N Tsuchida M Shibuya T Ide 《Cell structure and function》1990,15(6):385-391
tsJT60 is a nonlethal temperature-sensitive (ts) mutant of a Fischer rat cell line (3Y1) classified as a G0 mutant; i.e., the ts defect is not expressed within the cell growth cycle but is expressed only between the G0 and S phase. tsJT60 clones transformed with oncogenes such as adenovirus E1A, polyoma large T, polyoma middle T, v-Ki-ras, and LTR activated c-myc, or with a chemical carcinogen N-methyl-N'-nitro-N-nitrosoguanidine, grew well at 34 degrees C. However, most of these clones grew slowly at 40 degrees C, producing many floating dead cells, and some clones were killed at 40 degrees C. When they were cultured under conditions inadequate for growth of untransformed cells, such as high cell density or serum restriction, they were killed at 40 degrees C. These and previous results from SV40- and adenovirus-transformed tsJT60 clones favour the idea that transformed tsJT60 cells occasionally enter the G0 phase and are metabolically imbalanced at 40 degrees C during self-stimulation from the G0 to S phase. We propose that a drug which exclusively block, G0-G1 transition would be cytocidal to transformed cells but cytostatic to normal cells. 相似文献
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Dar-Fu Tai Ching-Chong Huang Hui-Yao Huang Ing-Lung Shih 《Biotechnology letters》1993,15(12):1229-1232
Summary Enzymatic hydrolysis of racemic 3-acetylthio-2-methylpropionic methyl ester catalyzed by bovine pancreatic protease and Mucor javanicus lipase showed opposite enantioselecivity. A tandem hydrolysis of the ester catalyzed by these two enzymes gives enantiomerically enriched (S)-3-acetylthio-2-methylpropionic acid, a building block of captopril. 相似文献
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