Comparative analysis of chromosomal nucleolar organizing region activity in spontaneous and medical abortuses]

Comparative analysis of functional activity of silver stained nucleolar-organizing regions (NOR) activity was carried out in human fibroblasts of 70 spontaneous and 50 medical abortuses. The NOR activity was significantly higher in spontaneous abortuses compared with medical ones. This phenomenon which was observed in female, but not in male abortuses, did not depend upon the tissue origin of fibroblasts (embryonic or extraembryonic) and was due to increase of the NOR activity of the all acrocentric chromosomes to the level at which individual differences in the NOR activities among some acrocentrics were smoothed. It has been suggested that the ribosomal genes activity in different sex is likely to be differently involved in polygenic systems determining vitally important features of organism that may lead to different selection intensity in different sex resulted in deviation of the ribosomal gene copy number from the optimum. The possible role of changes in DNA methylation at the genome level in activation of ribosomal genes in spontaneous abortuses is discussed.     

Genetic and phenotypic differences between thistle populations in response to habitat and weed management practices

Rapid evolutionary change is increasingly being recognized as commonplace, but the evolutionary consequences for species and ecosystems under human‐induced selection regimes have not been explored in detail, although many species occur in such environments. In a common garden experiment and with amplified fragment length polymorphism markers, we examined whether genetic differentiation has taken place between spatially intermixed populations of creeping thistles Cirsium arvense (Asteraceae) collected from a natural habitat (maritime shores), a semi‐natural habitat (road verges) and arable fields under two management regimes: conventional and organic farming. Populations of C. arvense have altered genetically and locally adapted their growth patterns with changed land use. Although plants from different habitats showed similar total biomass production, shoot and root production was higher for maritime populations, suggesting selection for increased competitive ability. Competitive ability then declined in the order semi‐natural, conventional farms and organic farms. Thistles in arable fields may be more selected for tolerance against disturbances from herbicides and mechanical weed control. In addition, early shoot sprouting and genetic analysis showed differentiation between plants originating from conventional farms and farms that were converted to organic 9–30 years ago, suggesting some adaptation to altered crop cultivation practices. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 797–807.     

Activities of cAMP-dependent protein kinase and enzymes of 2′,5′-oligoadenylate metabolism in NIH 3T3 cells deepening into the resting state

The activity of cAMP-dependent protein kinase was found to increase continuously in the NIH 3T3 cells, deepening into the resting state. The increase correlated with intracellular level of heat-stable protein inhibitor of the protein kinase rather than with the cAMP content. The elevation of 2',5'-oligo(A) synthetase activity and the decrease in 2'-phosphodiesterase activity were also observed in the cells sinking into the resting state. The variations in enzyme activities were similar to those caused by the increase in the intracellular cAMP content described elsewhere. These results agree with the idea that the cAMP-dependent protein kinase is involved in the regulation of the enzymes of 2',5'-oligo(A) metabolism.     

Change in the activity of DNAse I inhibitor in the mouse spleen on the administration of a synthetic polyanion

Synthetic polyanion pyran (copolimer of divinyl ether and maleic anhydride) injected to mice increases the titre of antibody to sheep red blood cells as well as the activity of serum DNAase I and DNAase I splenic inhibitor. Simultaneously a growth of the spleen weight takes place. A possible role of the DNAase I inhibitor system in the mechanism of the adjuvant action of synthetic polyanion is discussed.     

Phenotypic effect of the functioning of nucleolar-organizing regions of human chromosomes

Effects of functioning of nucleolar-organizing regions (NOR) of human chromosomes on a number of quantitative morphophysiological traits were studied. Sexual dimorphism of correlation of chromosomal functional polymorphism with some morphophysiological traits was revealed. Statistically significant positive correlations of ribosomal genes total activity with height, weight, chest circumference and diastolic blood pressure have been found in females but not in males. The data obtained suggest that functional activity of rRNA gene clusters in individuals of different sexes may exert different modifying effect on the level of expression of great number of genes responsible for some quantitative traits in man.