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Galindez Island is an island, lying in the Argentine Islands, Wilhelm Archipelago. Island is a monitoring polygon where according to the old British data archive, nowadays possible to monitor the impact of climate and human factors on terrestrial ecosystems. According to this, vegetation mapping was prepared. In particular, the area generally covered by vegetation of different types was mapped. It was necessary seeing that separate vegetation formations often create a complicate complex on the same area. In particular the moss-carpet sub-formation occupies spaces between the rocks, while the fruticose lichen and moss cushion sub-formation occupies rocks in same surface of the relative high relief elements that are released from the snow on the summer. On other hand, part of relatively low rocky surfaces is covered by poor disperse vegetation of green algae and crustose lichens. Discretely mapping was possible only to some vegetation types with largest continuous stands like Polytrichum strictum Brid moss banks. Deschampsia antarctica E. Desv. and Colobanthus quitensis (Kunth) Bartl. mainly grow in addition to wide spread moss carpet moss-carpet sub-formation and also were mapped. The main factors influencing the various components of vegetation are the expansion of the nesting colonies of the Gentoo penguin, that leads to the degradation of pre-existing vegetation types and the formation of limiting area groups of nitrophilic algae and groups of pure D. antarctica at their periphery territory. As well mapping of vegetation was also started, including well-mapped groups of moss banks on other islands of the Argentine Islands region. Particular attention is paid to the spread of rare forms (in particular, the chromosomal forms of D. antarctica) and the species of vascular plants - Colobanthus quitensis, mosses and lichens. This information will be used for the creation of new strictly protected areas (Ia IUCN) in the region. [ABSTRACT FROM AUTHOR]

Deschampsia antarctica E. Desv. - the species that for a long time has been adapted for harsh living conditions in the periglacial zones of South America, Subantarctic and maritime Antarctic. These fact causes interest in studying of its adaptive mechanisms, in particular on the anatomical level. In our study, we investigated plants of various chromosome forms with normal karyotype 2n = 26: Great Yalour Isl.- lines Y62 and Y67, Berthelot Isl.- BE1, Lahille Isl. - L59, karyotype with B-chromosomes 2n = 26 + 1-3B: Darboux Isl.- DAR12 and hipo-triploid 2n = 36, 38, 39 (Great Yalour Isl. - line Y66) grown from seeds collected in Argentine Islands region. These forms are micro-propagating in vitro as separate lines in unified laboratory conditions. The leaf anatomical structure of D. antarctica without any specific peculiarities was shown on the example of plants of Y62 and Y67 lines. It is interesting that in the course of the study, no qualitative particular features were found for plants hipo-triploid line Y66. Among the detected anatomical differences of leafs of DAR12 line plants a significantly larger number of stomata on the abaxial surface, a thicker adaxial epidermis and its outer cell wall, a larger bulliform cells, and a disorder of the epidermal cells placement were shown. On other hand, such disorder of the epidermal cells placement and double and triple stomata on the abaxial side of the leaf blade also are noted for plants of L59. It is also an abnormality, however these plants have 2n = 26. Mostly, plants micro-propagated in vitro have symmetrical 3-rib leaves, but also there were 5-rib leaves in plants from of L59 line, thus BE1 line were presented as plants with symmetrical 3-rib leaves and asymmetric 4-rib leaves. More over, a distinctive feature of BE1 plants was the presence of short small epidermocytes of square shape between conductive bundles and the single-celled non-glandular trichomes above the veins on both sides of the epidermis. The reasons of such heterogeneity will be clarified by studying a set of plants from the original localities in nature. This work was supported by the National Antarctic Scientific of Ukraine. [ABSTRACT FROM AUTHOR]

Aim. Determination of the sequence organization of the chromosomes terminal regions in Secale cereale L. varieties and some of its wild relatives for further identification of individual chromosomes with the use of appropriate probes. Methods. Fluorescence in situ hybridization, microscopy. Results. FISH analysis revealed 26-28 sites of the pSc200 sequence at the ends of all 14 pairs of chromosomes and 18 signals of the pSc250 sequence on the chromosomes of S. cereale in four accessions. Repeats were differently localized on the chromosomes of the closely related species Dasypyrum villosum and Dasypyrum breviaristatum, so it can be assumed that the tetraploid D. breviaristatum has an allopolyploid origin, may not be a descendant of D. villosum. Conclusions. A characteristic distribution of pSc200 and pSc250 tandem repeats of the tribe Triticeae was established, which allows revealing the evolutionary relationships between the studied species and the directions of their divergence. [ABSTRACT FROM AUTHOR]

Aim. Deschampsia antarctica Desv. is a unique species in the family Poaceae that occupies the Antarctic Peninsula region and demonstrates adaptation to the local unfavorable environments. It is well known that the stressful environmental factors can influence the plant genome by causing changes in the chromosome number and structure, as well as an increase in the genetic variation. Therefore, our study was aimed at investigating alterations in the genome of D. antarctica plants at both chromosomal and molecular levels that may be an important source of adaptive variation within the species. Furthermore, the genome stability was studied in the micropropagated plants and tissue cultures of the species. Methods. In the study we used in vitro grown D .antarctica plants that were derived from the seeds collected in the Argentine Islands region (Darboux, Galindez, Skua, Great Yalour Islands, and Rasmussen Cape) of Maritime Antarctic. The chromosome number of plants was determined in the cells of root apical meristems counterstained by DAPI. The 5S rDNA and 25S rDNA loci were visualized by the dual-color fluorescence in situ hybridization (FISH) technique. For cytological analysis the samples of tissue cultures derived from the root explants were fixed in ethanol : acetic acid = 3:1 and stained with 1% aceto-orsein. A molecular-genetic analysis was performed by PCR with polymorphic ISSR-primers. Results. Most of D. Antarctica plants from the Argentine Islands region have 2n = 26 chromosomes in their karyotypes. Moreover, the mixoploid plants were also found: accessions from Darboux Island (2n =13-27, 2n=26+1-2B) and Great Yalour Island (2n =13–39). FISH analysis revealed ten 5S rDNA sites and four 25S rDNA sites in the plant with the typical chromosome number (2n = 26). However, a greater number of rDNA loci (twelve of 5S rDNA and six of 25S rDNA) were found in the near-triploid plant from Great Yalour Island. The molecular-genetic analysis of D. antarctica plants demonstrated that the differences between the normal and mixoploid plants do not exceed the level of within population variation observed in the Argentine Islands region. The cytogenetic analysis revealed that tissue cultures have modal class composed of the cells with diploid and near-diploid chromosome number that indicates the conservation of cytogenetic features of D. antarctica genotypes at the early stages of culture irrespective of the karyotype of initial plant (diploid, mixoploid or poliploid). We failed to reveal the genetic changes in the clonally propagated D. antarctica plants during prolonged cultivation in vitro at both molecular (using ISSR-PCR) and chromosomal levels. The obtained results indicate that in vitro conditions used for the plant culture may ensure maintenance of the genome stability of D. antarcica. Conclusions. The cytogenetic analysis of D. antarctica plants revealed the intraspecies chromosomal polymorphism, which was further confirmed by FISH analysis. The molecular genetic analysis of the plants with different chromosome number demonstrated a low genetic diversity. The tissue cultures obtained from D. antarctica plants with the different karyotypes have similar cytogenetic structure with a predominance of diploid cells in the proliferative pool. [ABSTRACT FROM AUTHOR]

Deschampsia antarctica E. Desv. is one of the two flowering plants that, along with Colobanthus quitensis (Kunth) Bartl., was able to settle the ice-free areas of Antarctica. In order to identify the possible adaptations of the D. antarctica reproductive system to adverse environmental conditions, comparative cytoembryological analysis of plants of this species growing on the Antarctic Peninsula with plants of the closely related species D. beringensis Hult. from the Kamchatka Peninsula was conducted. It was found that both species are characterized by sexual mode of reproduction, equal size of pollen grains (25.5 ± 2.2 and 26.2 ± 1.9 μm, respectively), same features of the embryo sac structure, and emryo- and endospermogenesis. Interspecies differences have been found in mature embryo sac size (326.8 ± 12.8 and 161.7 ± 10.4 μm), pollen sterility percentage (86.1 ± 8.9 and 35.3 ± 9.2%), and quantity of pollen in the anthers (140 ± 15.3 and 1578 ± 88.6). Possible causes and significance of these differences are discussed. No unique adaptations of seed reproduction system that are inherent exclusively to D. antarctica were found. The D. antarctica reproduction strategy is based on the combination of autogamy (and its extreme form cleistogamy) with production of excess pollen quantity for its mode of pollination.

Cytogenetic analysis of Iris pumila L. plants from different habitats in Ukraine revealed the intrachromosomal polymorphism. Chromosome number 2n = 32 was established for plants of this species. Root meristem of I. pumila seedlings of all populations showed high level of mixoploidy. The differences in the percentage of aneuploid cells and anaphase aberration were found between the sampled populations. Anaphase analysis revealed the level of chromosomal rearrangements that reached 9.2% in some populations reached.

Comparative investigation of the soil contamination by polycyclic aromatic compounds (PAC) has been performed on examples of three polar stations of the Antarctic Peninsula. Data obtained are especially interesting for the Ukrainian Antarctic station "Academician Vernadsky" were no such investigations were performed since the technogenic spill of the hydrocarbons in 1992. Results of investigations permit to establish the values of the total background level of the PAC pollution as the base for the further monitoring of anthropogenic contamination. The data of analysis of soils from the all ecological zones of Point Thomas oasis (Polish Station "Genrik Artstovskiy") show the PAC homogenous background pollution to be similar to identified at the Galindez Island (the region of the station Academician Vernadskiy). Local pollutions are revealed in some areas of the Galindez Island. At the same time results of the investigation of the soils pollution from the various areas of the Fildes Peninsula (the station Bellingshausen.) show the absence of clearly pronounced contrast between the background and "hot points" that is likely related with the even pollution of the Peninsula. There was demonstrated the necessity of the development of regional standards and the establishment of a local background concentrations of PACs within the Antarctic Peninsula. At the same time, significant differences between the contamination of soils taken from the stations"Academician Vernadsky" and "Bellingshausen", apparently are associated with a lesser capacity of soils on the island Galindez that in the commensurable pollution creates greater concentrations in an investigated sample of the soil. There was shown the necessity of the development of the regional standard and the establishment of a local background concentrations of PACs within the Antarctic Peninsula.

The features of genetic structure and level of diversity were investigated for G. lutea populations from Chornohora Ridge of Ukrainian Carpathians using RAPD- and ISSR-PCR. We have shown a high level of genetic diversity for investigated populations. The differences between populations account for 59-72% of the total genetic variation, whereas intrapopulation polymorphism makes up 28-41%. The relationships among genetic variability level and ecological-geographical conditions as well as biological features of the species were assumed to be possible. The obtained results indicate the genetic isolation of G. lutea Chornohora populations from Ukrainian Carpathians. Pozhyzhevska agropopulation was characterized by a high level of polymorphism that means the possibility to use artificial plantings of the investigated species for its conservation.

Under the environmental conditions of the Point Thomas Oasis (King George Island, the South Shetland Islands), we studied the influence of month-long artificial treatment with fresh water, salt water, and guano solution on the biometric characteristics, chlorophyll content, as well as the nuclear area of leaf parenchymal cells and nuclear DNA content, in a maritime Antarctic aboriginal plant Deschampsia antarctica. The modeled factors induced an increase in the generative shoot height and the length of the largest leaf, but did not influence the number of flowers. Treatment with guano caused an increase in the chlorophyll a and b contents, while fresh water treatment only led to some increase in chlorophyll a. Fluctuations of physiologically significant traits, such as the nuclear area and DNA content in the leaf parenchyma cells of D. antarctica, have been traced under the influence of the studied factors. Understanding of the hierarchy of influence of these factors as well as and sensitivity of plants of this species to external agents require further investigation.

Components of three investigated plant extracts obtained from biomass of Ungernia victoris, Rhodiola rosea and Polyscias filicifolia cultivated cells interact with OmpC and OmpF proteins-porins and decrease their activity of as receptors in regard to OmpC- and OmpF-dependent bacteriophages. Entrance into cell of these components optimizes LPS synthesis and promotes increasing of receptor activity both itself LPS and OmpA and LamB proteins tightly connected with it.

Cytogenetic analysis of plants and tissue culture of Gentiana lutea, G. punctata, G. acaulis has been carried out. Culturing in vitro was found to result in the changes of chromosome number in the calluses of the species involved. Species specificity for variation of the cultured cell genomes was shown. Contribution of the original plant genotypes to the cytogenetic structure of the tissue culture was established. Gentiana callus tissues (except for in vitro culture of G. punctata, derived from plant of Breskul'ska population) were found to exhibit modal class with the cells of diploid and nearly diploid chromosome sets.

Chromosome numbers in root meristem cells of the seedlings of wild and cultivated Cruciferae species able to hybridize with Brassica napus have been studied. The seedlings of Brassica junceae, Diplotaxis tenuifolia and Raphanum raphanistrum showed exclusively diploid metaphases. Up to 5% of B. napus and B. cretica seedlings were mixoploids. Diploid cells prevailed among the mixoploids, but hypo- and hyperdiploid ones were observed as well. Nearly 20 % of B. campestris and R. sativum seedlings were mixoploid, and di-tetraploid chimeras constituted considerable proportion of them. Less than a half of B. nigra seedlings were diploid, while the rest of plants were mixoploid. Among them the seedlings bearing preferentially tetra- and triploid cells dominated. Biological implications and presumable reasons underlying the discovered mixoploidy are discussed.

Genome of Rauwolfia serpentina callus cells was found to fail undergo the noticeable changes for several early passages upon the switch from surface to submerged cultivation in the liquid medium of special composition. After subsequent 4-6 passages in submerged culture RAPD spectra polymorphism was revealed which may reflect the changes in DNA sequence as well as in the structure of cell population that forms the strain. Introduction of the intermediary passage on the agar-solidified medium of more simple composition prior to transfer into liquid medium appeared not to affect essentially the level and the pattern of genome changes.

Chromosome numbers of U. victoris cell lines obtained from the same bulb and cultured for a long time on different agar-solidified and liquid nutrient media differed significantly. The components of the nutrient media including phytohormones did not influence the ratio of cells with different ploidy levels in various lines while transfer of the calluses to the liquid media resulted in the increase of diploid metaphase frequencies.

A principle possibility of antitumour activity test in bacterial system represented by Escherichia coil of the wild type and its MS2-induced mutant has been shown. The initial bacterial strain is an indicator of toxic properties of the tested substances and the mutant one is a specific test-culture modelling a tumour cell. The comparison of the data described for eucaryotes with the data obtained using the proposed bacterial test system confirms an adequate response of both strains to the substances with the proved antitumour properties. The data are considered as very promising for the further improvement of this test system towards its application for primary screening of antitumour substances.

18S-25S rDNA of intact plants and tissue cultures of G. acaulis, G. punctata and G. lutea have been investigated by using blot-hybridization. The decrease of rDNA amount was found in the callus cultures as compared with the plants. In contrast to other species, G. lutea showed intragenome heterogeneity of rRNA genes as well as qualitative rDNA changes in tissue culture, in particular appearance of altered repeats. The relationship between the peculiarities of rRNA gene structure and their rearrangements in in vitro culture was suggested.

In the system of cation-induced E. coli transformation by the plasmid pBR322 the effects of the extract derived from the biomass of cultured cells of U. victoris on the correlation between yield of transformants, viability of CaCl2 - treated cells and plasmid DNA conformation alterations has been investigated. The data obtained have been compared with effects of some salts of one- and divalent metals on the same parameters. The presence of different mechanisms of the variations of cell population viability and yield of transformants depending on utilization of salts or plant extracts has been shown.

An analysis of 18S-25S and 5S rRNA genes in intact plants and cultured tissues of some Rauwolfia species was performed to compare these sequences variability occurred as a result of the species evolution in nature and that induced by tissue culture. The restriction fragment length polymorphism of 18S-25S and 5S rDNA was found both in intact plants of various Rauwolfia species and in long-term Rauwolfia serpentina tissue cultures. In addition, changes in the amount of 18S-25S rRNA genes were observed in long-term R. serpentina tissue cultures. The results demonstrate that rDNA variability observed in intact plants as well as in long-term cultures is attributed to differences in the same regions of ribosomal RNA genes.

Literature data on the production of naphthoquinoine pigment, shikonin, by the intact plants and cell cultures derived from the members of Boraginaceae family have been reviewed. The results of our own studies on generation of highly productive Arnebia euchroma cell lines able to accumulate up to 20% of shikonin in dry biomass are presented. Data on localization, application of naphthoquinoine pigments, peculiarities and enzyme control of their biosynthesis and transportation within plant cells and in culture in vitro are summarized.

Antimutagenic system is represented as the system combining all enzymatic and metabolic processes of the organism at all levels. The problem of supporting of autoantimutagenic system with antimutagenic preparations is discussed. A number of possible mechanisms of antimutagenic action of different substances are considered.

Literature data and the data of the author's investigations on production of isoquinoline alkaloids by Papaver bracteatum Lindl. have been analyzed. Information on the methods of regulation and cell localization of morphine and sanguinarine biosynthesis is presented. The works studying differentiation processes in tissue cultures of bracteum poppy and relationship thereof with thebaine biosynthesis have been analyzed. Possible mechanism determining the induction of somatic embryos development and thebaine biosynthesis in the culture in vitro are proposed.

Ability of cell biomass extracts of some medicinal plants to inhibit spontaneous segregation of new forms in E. coli MS2-induced unstable mutants system has been shown. The effect described is analyzed from the position of stabilizing activity of extracts concerning bacterial envelope membranes. The possible use of this bacterial system to study stabilizing effect as a separate stage of the known antimutagen protective action is discussed.

18S-25S rDNA sequence in genomes of G. lutea plants from different natural populations and from tissue culture has been studied with blot-hybridization method. It was shown that ribosomal repeats are represented by the variants which differ for their size and for the presence of additional HindIII restriction site. Genome of individual plant usually possesses several variants of DNA repeats. Interpopulation variability according to their quantitative ratio and to the presence of some of them has been shown. Modifications of the range of rDNA repeats not exceeding intraspecific variability were observed in callus tissues in comparison with the plants of initial population. Non-randomness of genome modifications in the course of cell adaptation to in vitro conditions makes it possible to some extent to forecast these modifications in tissue culture.

The analysis of literature data on production of isoquinoline alkaloids by Papaver somniferum L. plants and cell cultures has been made. The relationship of morphinane alkaloids biosynthesis with the processes of tissue and cell differentiation are discussed. The information on enzymes and pathways of regulation of morphine and sanguinarine biosynthesis are presented. The data on sanguinarine and morphine physiological role are analyzed.

Mapping of rRNA genes in four species of Gentiana genus has been carried out by blot-hybridization method using some restriction endonucleases. The following characteristics of Gentiana rDNA structural organization have been revealed: 1) interspecific and intragenomic variability of the length of ribosomic repeats; 2) conservativity of the transcribed region; 3) variability of the length and location of Hind-III site in non-transcribed spacer; 4) interspecific variability of the number of copies. Comparative analysis of the constructed restriction maps of Gentiana species and some other plants revealed the similarity of restriction site location in the transcribed DNA region.

The comparative study of the genomes of intact plants-representatives of some species of the genus Gentiana L. as well as cultured cells of G. lutea and G. punctata was performed using restriction analysis. Species specificity of restriction fragment patterns for studied representatives of this genus was revealed. The differences between electrophoretic patterns of digested DNA purified from rhizome and leaves of G. lutea and G. punctata were found. The changes in genomes of G. lutea and G. punctata cells cultured in vitro compared with the genomes of intact plants were detected. The data obtained evidence that some of them may be of nonrandom character.

Antimutagenic activity of 20 and 40% ethanol extracts from the biomass of Rhodiola rosea, Polyscias filicifolia, Panax ginseng and Ungernia victoris cultured cells have been studied. DDDTDP, ethidium bromide, benz(a)pyrene, benzidine served as model mutagens for Salmonella typhimurium TA 98 strain (the latter two were tested in presence of metabolic activation system); for S. typhimurium TA 100 strain these were tio-tefa, bichromate potassium and sodium azide and heavy metal compounds (chlorides of manganese, zinc, cadmium, lead acetate) for both strains. Higher capacity of the extracts from the biomass of R. rosea and P. filicifolia to counteract gene mutations induced by various mutagens was demonstrated (ca. 90% inhibition in isolated cases). In the experiment with the metabolic activation most effective proved to be the extracts from the P. ginseng biomass (up to 34% and 47% mutagenicity inhibition).

In this paper we demonstrate that apoptosis in primary culture of murine thymocytes and in continuously growing human cells is associated with the progressive disintegration of nuclear DNA into high molecular weight (HMW)-DNA fragments of about 50-150 kb. We also show that the formation of similarly sized HMW-DNA fragments takes place in the same cells in the absence of apoptotic inducers. Unlike an apoptotic fragmentation of nuclear DNA, the formation of HMW-DNA fragments in nonapoptotic cells is rapidly induced, has no correlation with the cell death, and is not associated with the development of oligonucleosomal "ladder" or apoptotic changes in nuclear morphology. The disintegration of DNA into HMW-fragments is also observed in nuclei isolated from healthy, nonapoptosizing tissues of various eukaryotes. We show that the formation of HMW-DNA fragments in the absence of apoptotic inducers is strongly dependent on the ionic detergents, is responsive to the topoisomerase II-specific poison, teniposide, and is completely reversible under conditions that favor topoisomerase II-dependent rejoining reaction. Also, we demonstrate that the formation of HMW-DNA fragments in continuously growing cell lines caused either by serum deprivation or monolayer establishment is of a transient nature and rapidly reverses to the control level following serum addition or dilution of monolayer. The results suggest that the cleavage of nuclear DNA into HMW-DNA fragments is associated not only with apoptosis but also accompanies changes in functional activity of nonapoptotic cells.

The authors studied teh effect of cultured Polyscias filcifolia Bailey cells on protein biosynthesis in an acellular system obtained from the liver of rabbits in experimental myocardial ischemia. It was found that the preparation normalizes the values of protein biosynthesis, the duration of the average polypeptide chain synthesis, and the activity of aminoacyl-tRNA synthetases.

The data presented confirm the possibility of enzymatic formation of discrete DNA-fragments appearing during fractionation of nuclear DNA by FIGE. Teniposide-dependent pattern of DNA-fragments as well as occurrence of protein-linked DNA breaks suggest that discrete cleavage of intact nuclear DNA is modulated by DNA topoisomerase II. The possible relationship between discrete DNA-fragments and the higher order chromatin folding are discussed.

The fractionation of eukaryotic DNA by field inversion gel electrophoresis results in the appearance of discrete DNA-fragments. The set of these fragments is similar to that of different eukaryotic representatives and consists of various chromosomal DNAs, unified by size. The physical properties of DNA-fragments suggest that they can form multimeric structures due to the presence of sticky ends flanking discrete fragments. We suppose that the set of discrete DNA-fragments results in a specific cleavage of intact nuclear DNA and can reflect different levels of chromatin structural organization.

The experiments on chromosome variability of cells in the ontogenesis of higher plants are reviewed. The polyploidization of somatic cells during the ontogenesis is shown to be the natural phenomenon for most plant tissues and it is correlated with the intensification of cellular metabolism. The functional and chromosome variability of somatic cells is supposed to depend mostly on the hormonal regulation. The possible role of the phytochrome system in this process is discussed.