TSitologiia i genetika最新文献

The formation of different types of the artifacts in the amplification reaction with using different classes of the molecular-genetic markers (Indel and SSR) was studied. It was shown that DNA heteroduplexes formed during amplification of heterozygous samples, as fragments of target genes and microsatellite loci. During the electrophoresis in native polyacrylamide gel of the amplification products of homozygous samples for microsatellite loci it was revealed specific additional fragments that do not belong to the class of heteroduplex DNA. It was supposed, that the additional fragments belong to a special type of homoduplex DNA – non-linear homoduplexes. The analysis revealed that the formation of a non-linear homoduplex DNA takes place on the 20–25 cycle of the PCR, both at the amplification of the individual samples, and individual DNA fragments that was cut out from the gel.

The objective of this investigation was to analyze possible association between BclI polymorphism of glucocorticoid receptor gene and obesity in patients with bronchial asthma (BA). The study involved 188 patients with bronchial asthma and 95 apparently healthy adult individuals. Generally accepted assessments and examinations for BA diagnosis, and anthropometric, molecular-genetic and statistic methods of investigation were used in the research. It was found out that the patients with BA demonstrated higher body mass index (BMI) and higher ratio of fat centralization much more often, than the control group. Genotypes distribution for BclI polymorphism in patients with BA showed a statistically significant difference between patients with different BMI unlike the control group. Comparison of genotype frequency for BclI polymorphism in glucocorticoid receptor gene in individuals with different ratio of fat centralization in the control group and in the patients with BA separately showed statistically significant differences in the distribution of gene allelic variations only among the patients with BA. It was demonstrated that G/G genotype in the patients with visceral obesity was associated with BA.

The research has shown that exposure to ionizing radiation at the dose of 30 cGy leads to the activation of NO-synthase way of nitrogen oxide synthesis, as well as to the accumulation of its stable metabolites and 3’-nitrotyrosine modified proteins in rat peripheral blood leucocytes and the renal cortical layer. NO-synthase activity was preserved at the control value through the consumption of red wine natural polyphenolic complex concentrates by the irradiated animals. The content of proteins modified by tyrosine nitration decreased in the early period of post-radiation exposure due to the influence of the investigated concentrate. Thus the ability of red wine natural polyphenolic complex concentrates to prevent adverse changes in L-arginine/NO system and, therefore, inhibit the development of nitrative stress induced by low doses of ionizing radiation has been proved experimentally.

In the article the data on the distribution of CYP21A2 gene mutations (gene deletion/conversion, c.290-13C>A/G, E110Vfs, I172N, cluster of mutations I236N, V237E, M239K, V281L, Q318X, R356W) among Ukrainian patients with congenital adrenal hyperplasia of different clinical phenotypes are presented. The most common mutation in the studied group (n = 27) is the CYP21A2 gene deletion/conversion. Possible patterns of the studied mutations distribution in different populations of the world and the patients’ genotype – phenotype association are discussed.

Molecular-genetic study of C-590T polymorphic locus of IL-4 gene in 31 children with recurrent episodes of acute obstructive bronchitis and 50 people who constituted the control population-based group has been carried out. It is proved that the presence of this polymorphic locus leads to three-fold increase of the risk of acute obstructive bronchitis recurrent episodes.

In this study there were investigated the changes in surface marker CD44 in human erythrocytes exposed to cryoprotective media, as well as the impact of oxidative modification of membrane-cytoskeleton proteins on the CD44 characteristics under the changed physico-chemical parameters of the cellular environment. Glycerol, DMSO, sucrose, and PEG-1500 were shown to cause a decrease in CD44 expression level and amount of CD44-positive cells during prolonged exposure erythrocytes with them. That may reflect subtle adjustments in the system of protein-protein interactions in erythrocyte membrane-cytoskeleton complex, which may affect the stability of cells during cryopreservation. Extracellular substances (sucrose and PEG-1500) exhibited a more pronounced effect on the CD44 in erythrocytes in comparison with the examined substances of endocellular type. Modification of membrane-cytoskeleton proteins with oxidizing bifunctional reagent diamide enhanced the identified tendencies.

Root anatomy, cytoskeleton orientation and cell wall thickness in cells of the roots formed de novo in vitro under clinorotation (simulated microgravity) were investigated. Structure of the embryonic roots and of the roots formed de novo in cambium cells of the leaf petiole explants was shown to be similar. Root cell differentiation in vitro under clinorotation did not differ from that in control. Changes of tubulin microtubules' orientation in the epidermis of the distal elongation zone were observed under clinorotation that seems to be associated with specific physiological properties of the cells. Under clinorotation, the tendency of cell wall thinning was detected in the root cells formed in vitro.

Strict response is a pleiotropic physiological response of cells caused by lack of aminoacetylated tRNAs. Experimentally, this response occurs due to the lack of amino acids in the environment and the limitation of tRNA aminoacylation even in the presence of the corresponding amino acids in the cell. Many features of this response indicate its dependence on the accumulation of ppGpp molecules. There is a correlation between the growth rate of actinomycetes and biosynthesis of their secondary metabolites. Introduction of additional relA gene copies of ppGpp synthetase can affect the production of antibiotics in streptomycetes. The article presents the authors' own experimental data, dedicated to the influence of heterologous relA gene expression in Streptomyces nogalater cells.

Spontaneous mutations are thought to have a stable rate for a given species. If non-adaptive, they appear at low frequencies and are governed by drift. However, environmental factors have been reported to cause spread of non-adaptive mutations in populations, governed by mechanisms, such as genetic assimilation. In the present study, we report a simultaneous appearance of a mutant and apparently non-adaptive C2 vein in Drosophila melanogaster at higher than expected frequencies in several distant populations, which excludes the role of drift or selection as the cause of the reported mutation frequencies. We discuss explanations of the phenomenon, including the role of externalfactors, such as temperature, in the possible genetic assimilation of the trait.

Comparative studies of genetic variability were undertaken for 12 allozyme loci selections of trees and embryos of seed, and also for the crossing systems in five populations of Koch pine of (Pinus kochiana Klotzsch ex Koch) in Crimea. It was shown that in seed embryos the allelic variety peculiar to the maternal plants was restored, however the level of the available (H₀) heterozygosity was considerably lower, 0.286 and 0.189 respectively. For the embryos unlike the trees, in the majority of the analyzed loci the considerable divergence was specific in the actual distribution of genotypes from the theoretically expected according to Hardy- Weinberg law. The proportion of cross pollination at the unilocal (t(s)) estimation varied from 0.384 to 0.673 in the populations, while at the multilocal ones (t(m)) it was 0.639-0.841.