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81.
ABSTRACT

Population estimates of male Western Capercaillies Tetrao urogallus were carried out during the mating season using two methods: counts of singing males and non-invasive genetic analysis. Estimates of male numbers were 50% lower using the singing counts compared to the estimates obtained through genetic analysis, and underestimates were greatest when the number of Capercaillies was lowest.  相似文献   
82.
Metastatic cancer cells are highly plastic for the expression of different tumor phenotype hallmarks and organotropism. This plasticity is highly regulated but the dynamics of the signaling processes orchestrating the shift from one cell phenotype and metastatic organ pattern to another are still largely unknown. The scaffolding protein NHERF1 has been shown to regulate the expression of different neoplastic phenotypes through its PDZ domains, which forms the mechanistic basis for metastatic organotropism. This reprogramming activity was postulated to be dependent on its differential phosphorylation patterns. Here, we show that NHERF1 phosphorylation on S279/S301 dictates several tumor phenotypes such as in vivo invasion, NHE1-mediated matrix digestion, growth and vasculogenic mimicry. Remarkably, injecting mice with cells having differential NHERF1 expression and phosphorylation drove a shift from the predominantly lung colonization (WT NHERF1) to predominately bone colonization (double S279A/S301A mutant), indicating that NHERF1 phosphorylation also acts as a signaling switch in metastatic organotropism.  相似文献   
83.
DNA samples of unrelated subjects from the Volga-Ural region of Russia were examined to study allele polymorphism of the pentanucleotide repeat (TTGTG)8 localized to an intron of the tumor suppressor gene ING1. STR marker was registered in the EMBL database with the accession number AJ277387. In a sample of 119 individuals, three pentanucleotide alleles consisting of seven, eight, and nine repeated monomers were revealed. The allele frequencies were 0.24, 0.74, and 0.02, respectively. Heterozygosity was 0.45. On the basis of these data, the repeat can be regarded as a polymorphic STR marker for the ING1 gene and used in population and clinical studies.  相似文献   
84.
The human CKAP2 gene, which is involved in diffuse large B-cell lymphomas, was localized via screening the GeneBridge 4 somatic cell radiation hybrid panel by means of the polymerase chain reaction (PCR). The CKAP2 gene was mapped between the WI-15460 and WI-3673 markers at the boundary between regions 13q14.3 and 13q21.1, at the distance of 14.39 cR (with 4.8 cR per cM) from the WI-5867 framework marker (lod score > 2.26). The human CKAP2 gene displayed high homology to mouse and rat expressed orthologs, A CKAP2-like sequence was found in human chromosome 14 and assumed to be a pseudogene resulting from duplication and subsequent mutations of the CKAP2 gene on chromosome 13. A possible role of the CKAP2 gene in oncogenesis associated with deletions and rearrangements of region 13q14.3-21.1 is discussed.  相似文献   
85.
The bacterial hemoglobin vhb gene was cloned from sliding bacterium Vitreoscilla sp. as an element of the system ensuring survival of this microorganism in an environment that contains insufficient amount of oxygen. The vhb gene was transferred from Escherichia coli to some Streptomyces strains, producers of antibiotics, by the method of intergeneric conjugation using conjugative-integrative plasmid vectors pIH1 and pCH2. The stability of plasmid DNA inheritance was analyzed in the genomes of exconjugants. A positive effect of the vhb gene on processes of conjugation and antibiotic production in a number of examined strains was shown.  相似文献   
86.
The distribution of alleles and haplotypes of three diallellic Y-specific loci (YAP, DYF155S2, and Tat) in the populations of Kyrgyz, Uzbeks and Tajiks was analyzed. In Kyrgyzes and Uzbeks, a relatively high frequency of the DYF155S2 deletion (20 and 12.5%, respectively) and the C allele at the Tat locus (11.2 and 8.3%, respectively) were revealed. In the populations of southern Kyrgyzes and Uzbeks, two chromosomes carrying the YAP+ allele were detected. In both cases the YAP+ allele was found within the YAP+/DYF155S2+/TatT haplotype. The Tajik population was monomorphic in respect to the polymorphisms studied. The Tajiks demonstrated the presence of only the YAP-/DYF155S2+/TatT haplotype. This haplotype appeared to be most frequent in Kyrgyz (78.8%) and Uzbeks (83.3%). The question on the origin and the distribution of Y-chromosome variants in Eurasia are discussed.  相似文献   
87.
It is shown that bacterial genes for thermostable beta-glucanases are expressed retaining their activity and substrate specificity. The leader peptide of the carrot extensin exerts effective secretion of the bacterial enzymes into the intercellular space of the plant tissue. Expression of the bacterial gene for beta-1,3-glucanase in plant tissues alters their morphogenetic potential. Regeneration of shoots from the calli of these plant lines requires a six- to eightfold increase in cytokinin (6-BAP) concentration in comparison with the control lines and the transgenic lines expressing beta-1,3-1,4-glucanase. Rooting of transgenic plants expressing the bacterial gene for beta-1,3-glucanase occurs much faster. The transgenic plants obtained in the study are proposed as model objects for investigating the role of glucanases in plants.  相似文献   
88.
Surnames are traditionally used in population genetics as "quasi-genetic" markers (i.e., analogs of genes) when studying the structure of the gene pool and the factors of its microevolution. In this study, spatial variation of Russian surnames was analyzed with the use of computer-based gene geography. Gene geography of surnames was demonstrated to be promising for population studies on the total Russian gene pool. Frequencies of surnames were studied in 64 sel'sovets (rural communities; a total of 33 thousand persons) of 52 raions (districts) of 22 oblasts (regions) of the European part of Russia. For each of 75 widespread surnames, an electronic map of its frequency was constructed. Summary maps of principal components were drawn based on all maps of individual surnames. The first 5 of 75 principal components accounted for half of the total variance, which indicates high resolving power of surnames. The map of the first principal component exhibits a trend directed from the northwestern to the eastern regions of the area studied. The trend of the second component was directed from the southwestern to the northern regions of the area studied, i.e., it was close to latitudinal. This trend almost coincided with the latitudinal trend of principal components for three sets of data (genetic, anthropological, and dermatoglyphical). Therefore, the latitudinal trend may be considered the main direction of variation of the Russian gene pool. The similarity between the main scenarios for the genetic and quasi-genetic markers demonstrates the effectiveness of the use of surnames for analysis of the Russian gene pool. In view of the dispute between R. Sokal and L.L. Cavalli-Sforza about the effects of false correlations, the maps of principal components of Russian surnames were constructed by two methods: through analysis of maps and through direct analysis of original data on the frequencies of surnames. An almost complete coincidence of these maps (correlation coefficient rho = 0.96) indicates that, taking into account the reliability of the data, the resultant maps of principal components have no errors of false correlations.  相似文献   
89.
Frequency distribution of several genetic markers was studied in ethnic Russians from the Moscow, Bryansk, Ryazan', Kostroma, Novgorod, Arkhangel'sk, and Sverdlovsk oblasts and Udmurtiya. Systems AB0, RH, HP, TF, GC, PI, C'3, ACP1, PGM1, ESD, GLO1, 6PGD, and AK were analyzed in most samples. New data on informative polymorphic genetic loci showed that the Russian gene pool mostly displays Caucasoid features. In addition, Y-chromosomal short tandem repeats (STRs) DYS19, DYS390, and YCAII were analyzed in the Russian samples. STRs of the chromosome are particularly valuable for elucidating ethnogenetic processes in Eastern Europe. Frequency distributions of the Y-chromosomal markers in Russians were intermediate between those of West European populations and eastern Finno-Ugric ethnoses of the Volga region. A marked longitudinal gradient was revealed for frequencies of several molecular markers.  相似文献   
90.
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