Oscillatory Cs-137 Distribution Pattern in Scotch Pine Bark.

The vertical distribution of the anthropogenic radionuclide Cs-137 in the Scots pine (Pinus sylvestris L.) bark was studied in two model trees in the radioactive contamination zone of the Bryansk region. Each tree was divided into 10-cm bars from the trunk base to a length of 17 m, and the bark with the bast was separated from each bar to obtain a separate sample. In addition to Cs-137, the natural radionuclide K-40 was measured in the bark of model tree 2 from the trunk base to a 6.5-m length. Specific activities of Cs-137 and K-40 were measured by γ-ray spectrometry. The vertical distribution of Cs-137 in the bark was for the first time observed to have a wave-like pattern with a period of approximately 1 m. The K-40 distribution showed a similar oscillatory pattern, consistent with a similar mechanism responsible for potassium and cesium behavior in woody plants. The correlation coefficient between specific activities of Cs-137 in model trees 1 and 2 was 0.80; the correlation coefficient between Cs-137 and K-40 activities in model tree 2 was 0.45. Cs-137 was assumed to provide a radiotracer to assess the intake and distribution of chemical elements in Scotch pine tissues. The oscillatory pattern observed for the vertical distributions of cesium and potassium in the pine bark has not been described in the available literature before.

[Cloning of a new murine gene coding for a protein immunologically related to RecA protein from Escherichia coli]. / Klonirovanie novogo gena myshi, belok kotorogo immunologicheski rodstvenen RecA-belku Escherichia coli.

Using the testis-specific murine cDNA library immunoscreening with the affine-purified polyclonal antibodies to the E. coli RecA protein, the 1730-bp fragment of the novel mouse gene was cloned. Northern hybridization of total RNA samples from mouse somatic and meiotic tissues showed that this gene was specifically expressed in mouse testis, producing a transcript of about 10 kb in size. Analysis of the cloned cDNA sequence revealed the presence of the-AATAAA-polyadenylation site at its end, indicating that the cloned fragment represented the end part of the corresponding gene. Comparative sequence analysis revealed that the plus-chain of the cloned fragment contained motifs of the mouse RAD50 gene; the 378-bp fragment of the minus-chain showed 96% homology with the Homo sapiens Hd741-f cDNA fragment; and the whole minus-chain was by 50% homologous to the prokaryotic FTSZ/A genes. The cloned fragment contained two reading frames located in the plus- and minus-chains, respectively. The presumptive 44-kDa protein encoded by the plus-chain (sense) open reading frame contained serine-, proline-, and threonine-rich regions and was 25 to 30% homologous to a number of nuclear DNA-binding proteins of eukaryotes. Although analysis of the similarity between the 44-kDa protein and the E. coli RecA protein did not show any significant homology between them, it revealed their identity by five amino-acid residues involved in the formation of the epitope that recognized the paratope of the RecA protein antibody for subsequent epitope-paratope binding of these proteins.

[Cloning and determination of the structure of a new human gene, homologous to Saccharomyces cerevisiae rad proteins]. / Klonirovanie i opredelenie struktury novogo gena cheloveka, gomologichnogo Rad-belkam Saccharomyces cerevisiae.

Cloning of a novel Homo sapiens gene from cDNA libraries of human testes using immunoscreening procedure with affinity-purified polyclonal antibodies against E. coli RecA protein was carried out. The nucleotide sequence and chromosomal localization of this gene were determined. Computer modeling of its primary transcript was conducted. The gene investigated is localized on the P arm of chromosome 19 within the 19p13.1 cluster and consists of seven exons and six introns. It has a leader, 3' untranslated, and translated regions. The translated sequence encodes a 33-kD protein that displays 30-40% homology to the Saccharomyces cerevisae Rad proteins. TATA- and CAAT-like sequences are situated at positions -30 and -40 bp as well as -102 and -148, respectively. The absence of CCGCCC- or GGGCGG-like sequences may indicate that this gene is tissue-specific.

Use of DNA fingerprinting for human population genetic studies.

DNA fingerprinting techniques have been used in population genetic studies on many different kinds of organisms. Here, we present new applications for multilocus DNA fingerprint probes in population studies and demonstrate the applicability of DNA fingerprinting to human population genetics, using M13 phage DNA as a probe. The new approach, which is based on a factor method of numerical coding of nonquantitative data (factor correspondence analysis-FCA), shows good agreement between population position, as indicated by the three principal factors, and ethnogenetic proximity.

Genetic differentiation in a captive population of the endangered Siberian crane (Grus leucogeranus Pall.).

DNA fingerprinting, followed by multivariate analysis of data, was used to characterize genetic heterogeneity in captive populations of the endangered Siberian and sandhill cranes. The genetic structure revealed reflected the natural population and species distributions. The relevant groups differed not only from each other, but also from interspecies and inter-population hybrids bred in captivity. In this study we have tested an approach to the analysis of population structure based on individual genotypes. Interpretation of fingerprinting data by means of the analytical system applied here is a useful and reliable procedure for the estimation of genetic relationships between individuals.

[The relation between the variability of polygenic morphological and monogenic biochemical traits as exemplified by Karakul sheep]. / Izuchenie sviazi mezhdu izmenchivost'iu poligennykh morfologicheskikh i monogennykh biokhimicheskikh priznakov na primere karakul'skikh ovets.

A quantitative method for investigation of relationship between polygenic and monogenic traits has been proposed. It is based on examination of relationship between frequencies of distribution classes of an adaptive quantitative trait and frequencies of certain genetic character in the same classes. The method permits to locate a gene marker within a space of quantitative trait values. Using adaptively significant morpho-anatomic traits, it is possible to estimate indirectly adaptive values of gene markers under consideration, since, in accordance with the concept of adaptive norm, "average" phenotypes have maximal fitness, whereas deviative phenotypes transgress the bounds of the optimum. As a genetical character, genotype of certain biochemical locus, individual heterozygosity range or interlocus combinations of alleles could be used. The method has been applied to newborn Astrakhan lambs. Principal component analysis has been used to obtain complex characterization for six constitutional characters. Some regularities in location of homo- and heterozygous genotypes of the transferrin locus within a space of morphological characters' values have been revealed.