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761.
D. V. Leman A. F. Parshikov P. G. Georgiev O. G. Maksimenko 《Russian Journal of Genetics》2014,50(4):341-347
The SF1 insulator was found to contain a polyadenylation signal, which corresponded to the functional polyadenylation signal in embryonic S2 cells and the transgenic lines of Drosophila and bi-directional promoter that functioned in S2 cells. The studies performed did not confirm the ability of the SF1 insulator to protect expression of reporter gene white from the chromosome position effect in transgenic lines. 相似文献
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The barley chromosomal mutant T-35, in which only one pair of satellite chromosomes is apparent, was analyzed using a range of cytological and molecular techniques. Using conventional Feulgen staining, Giemsa and silver banding, in situ hybridization, and Southern blot analysis, unequivocal cytological and molecular evidence was obtained that T-35 is a homozygous deletion of rRNA genes residing in the nucleolus organizer region (NOR) of chromosome 6. According to the criteria of arm ratio and Giemsa-banding pattern of this chromosome, the deletion involved the whole NOR, one of the breakpoints being localized in the short arm proximally to the NOR-associated heterochromatic band, the other probably in the satellite of the chromosome. As a result of this deletion, an increased activity of the rRNA genes (as indicated by the size of the silver bands) on the other NOR-bearing chromosome (chromosome 7) was observed. The possible reasons for this phenomenon are discussed. 相似文献
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An important aspect of biological evolution is the development of biocatalyzers. The connection between abiotic and biological catalyzers is discussed, and the role of metal ions as primary catalysts is considered. The evolutionary demand for greater specificity and efficiency may have been fulfilled through the formation of metal-organic complexes and later through enzyme systems. Metal ions are probably responsible for the formation of some of the isoenzymes found in contemporary organisms. 相似文献
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Phytochemistry Reviews - The wide and not yet fully uncovered potential of plant secondary metabolites make plants a rich source of drug leads. Metabolomics enables the study of the metabolic... 相似文献