Genetic diversity of Besermyans inferred from mitochondrial DNA polymorphism

The first data are presented on mtDNA diversity in Besermyans, the Finno-Ugric ethnic group related to Udmurts. An analysis of mtDNA polymorphism showed that Besermyans stood out from the other populations of Volga-Ural region due to the presence of a large proportion of the Mongoloid component. The sample of Besermyans contained East Eurasian haplotypes not detected in ethnic populations of the Volga region and Cisurals, while they were detected in South Siberia, mostly among Turkic-speaking populations. An analysis of the genetic distances between Besermyans and the neighboring ethnic groups showed that Besermyans were distant from other populations of Volga-Ural region and close to Turkic-speaking populations of South Siberia. Thus, the data obtained favor the suggestion on the mixed Udmurto-Turkic origin of Besermyans.     

Some features of mitochondrial gene pool of Maeotis in light of their relation to Cis-Asov nomads

New data on mitochondrial gene pool polymorphism of Maeotis (1st–3rd centuries CE) in the light of their relation with Sarmatian nomads are presented. Maeotis are more genetically various, compared to Sarmatians; both the age of Maeotian gene pool and their close interactions with neighboring tribes can be reasons for this. The study of relationships of Maeotis and Sarmatians suggests an intensive gene interchange between them, which influences significantly on the formation of the Maeotian gene pool.

     

A new dimension in retrograde flow: centripetal movement of engulfed particles

Centripetal motion of surface-adherent particles is a classic experimental system for studying surface dynamics on a eukaryotic cell. To investigate bead migration over the entire cell surface, we have developed an experimental assay using multinuclear giant fibroblasts, which provide expanded length scales and an unambiguous frame of reference. Beads coated by adhesion ligands concanavalin A or fibronectin are placed in specific locations on the cell using optical tweezers, and their subsequent motion is tracked over time. The adhesion, as well as velocity and directionality of their movement, expose distinct regions of the cytoplasm and membrane. Beads placed on the peripheral lamella initiate centripetal motion, whereas beads placed on the central part of the cell attach to a stationary cortex and do not move. Careful examination by complementary three-dimensional methods shows that the motion of a bead placed on the cell periphery takes place after engulfment into the cytoplasm, whereas stationary beads, placed near the cell center, are not engulfed. These results demonstrate that centripetal motion of adhering particles may occur inside as well as outside the cell. Inhibition of actomyosin activity is used to explore requirements for engulfment and aspects of the bead movement. Centripetal movement of adherent particles seems to depend on mechanisms distinct from those driving overall cell contractility.     

Effect of preliminary adaptive irradiation on the concentration of lipid peroxidation products in blood serum and degradation of DNA in thymus of irradiated mice

The animals were irradiated within adaptive dose of 0.1 Gy and 5 hours later with a challenge dose of 2 Gy. The adaptive dose reduced the effects induced by the challenge dose of 2 Gy: the increased content of the products of lipid peroxidation reactive to thiobarbituric acid in blood serum, and the increased number of breaks in thymus DNA of irradiated mice.     

Comparative efficiency of injurious action of radiation and stress on thymus and lipid peroxidation

Exposure to radiation, as well as holding under conditions of limited mobility during 24 h, induced decrease in thymus cell number, increase in number of DNA breaks. The content the products of lipid peroxidation reactive with thiobarbituric acid in blood serum of mice decreased as well. The stress effect is comparable with radiation doses in the range of 50-60 cGy.     

Features of the Udmurt mitochondrial gene pool in relation to tribal structure

We present novel data on mitochondrial DNA polymorphism in the Udmurt population, which represents a Finno-Ugric ethnos residing in the Volga-Ural region. Our analysis of the Udmurt mtDNA polymorphisms have shown that neighboring ethnoses had almost no effect on formation of the Udmurtian intra-ethnic diversity. These results strongly indicate that genetic differences in the Udmurtian population are determined by their tribal structure rather than their geographic location.     

Macrophages Create an Acidic Extracellular Hydrolytic Compartment to Digest Aggregated Lipoproteins

A critical event in atherogenesis is the interaction of macrophages with subendothelial lipoproteins. Although most studies model this interaction by incubating macrophages with monomeric lipoproteins, macrophages in vivo encounter lipoproteins that are aggregated. The physical features of the lipoproteins require distinctive mechanisms for their uptake. We show that macrophages create an extracellular, acidic, hydrolytic compartment to carry out digestion of aggregated low-density lipoproteins. We demonstrate delivery of lysosomal contents to these specialized compartments and their acidification by vacuolar ATPase, enabling aggregate catabolism by lysosomal acid hydrolases. We observe transient sealing of portions of the compartments, allowing formation of an “extracellular” proton gradient. An increase in free cholesterol is observed in aggregates contained in these compartments. Thus, cholesteryl ester hydrolysis can occur extracellularly in a specialized compartment, a lysosomal synapse, during the interaction of macrophages with aggregated low-density lipoprotein. A detailed understanding of these processes is essential for developing strategies to prevent atherosclerosis.     

A Study of the Association between Breastfeeding and DNA Methylation in Peripheral Blood Cells of Infants

Russian Journal of Genetics - This article reports on new data on the association of breastfeeding with DNA methylation in the peripheral blood cells of 37 children aged from 9 months to four...     

The stromal colony-forming cell (CFUf) count in the bone marrow of mice and the clonal nature of the fibroblast colonies they form

The clonal nature of FCFC-derived stromal colonies was tested by chromosomal analysis in mixed cultures of CBA and CBAT6T6 bone marrow cells depleted of macrophages and myeloid cells. Inoculation of the bone marrow cell suspensions in flasks coated with poly-l-lysine has revealed practically no stromal aggregates among the explanted cells. The coincidence of karyotypes within the stromal colonies in the mixed cultures proved that the FCFC-derived colonies were cell clones. It was shown by indirect immunofluorescence with antibodies to type 1 collagen that the mouse bone marrow FCFC-derived colonies consisted of stromal fibroblasts. The cloning efficiency of the bone marrow FCFS depends on the explantation density of cells; a stable colony-forming efficiency could be reached only in the presence of feeder cells (irradiated bone marrow). In the bone marrow cells suspensions obtained by trypsinization the amount of FCFC is markedly higher than in the suspensions of mechanically disaggregated bone marrow cells.     

Polymorphism of immunogenetic and biochemical markers in Siberian (Tobol-Irtysh) Tatars

The polymorphism of immunogenetic and biochemical markers has been studied in nine populations of five ethnic-geographic groups of Siberian (Tobol-Irtysh) Tatars. Data on the frequency distributions of 33 alleles and 6 haplotypes of 14 loci (ABO, RHD, RHC, RHE, P, KEL, HP, C′3, TF, GLO1, ESD, ACP, PGD, and PGM1) in sample of 354 subjects have been obtained. Comparison with other ethnic groups has shown that the gene pool of Tobol-Irtysh Tatars contains an ancient autochthonic genetic stratum similar to that found in the neighboring Ob’ Ugrian population. Genetic relationships of various strengths with Central Asian Turks and the ethnic groups of the Volga region have been found, which apparently reflect different stages of the ethnogenesis of the Tobol-Irtysh Tatars.