Screening for mutations in BRCA1 and BRCA2 genes and related perspectives for the healthcare system

In the article there were looked some aspects of the knowledge regarding mutations in BRCA1 BRCA2 genes that have been accumulated since the first report on role of these genes in the development of breast and ovarian cancer. Most of them have practical worth related to the detection of mutations, as well as the prevention and treatment of associated ovarian cancer (the article focuses specifically on ovarian cancer, conditioned to relatively less amount of information on this pathology). There has been paid attention to the rational assignment of a genetic test on the presence of mutations in BRCA genes.Keywords: ovarian cancer, mutations in BRCA1 BRCA2 genes, screening of the presence mutations in BRCA1 BRCA2 genes.

Evolution of darwinism. A new evolutionary synthesis: combining evolutionary genetics and development genetics

The results of the synthesis of evolutionary genetics and developmental genetics are presented, the causes of the crisis of evolutionary genetics and ways to overcome it are explained, and the mechanism of speciation of higher organisms is explained.Keywords: new evolutionary synthesis, evolutionary genetics, genetics of ontogenesis, morphogenetic program, developmental genes.

Polymorphism of COI gene in honey bees from different regions of Ukraine

Aim. The rapidly evolving mitochondrial CoI gene is widely used in the molecular taxonomy of insects to identify closely related forms. Accordingly, to assess the distribution of subspecies / breeds of Apis mellifera in Ukraine, sequencing and comparison of this gene was performed for bees from different geographical regions. Methods. PCR amplification and sequencing of CoI. Results. Breed-specific mutations in the CoI gene have been identified for the Dark European, Carpathian and Ukrainian Steppe honey bees, which are widely distributed in Ukraine. It was found that the current distribution of these breeds does not correspond to the traditional zoning. Conclusions. The widespread practice of importing the genetic material of Apis mellifera from different regions of Ukraine leads to uncontrolled hybridization and represents a threat to the conservation of aboriginal breeds of honey bees.Keywords: biodiversity, mitochondrial DNA, molecular markers, cytochrome oxidase, Apis mellifera.

Molecular organization of 5S rDNA intergenic spacer in Gentiana pneumonanthe L. and G. punctata L.

Aim. The study was aimed at cloning and analysis of molecular organization of 5S rDNA intergenic spacer (IGS) in two Gentiana species of Ukrainian flora, G. pneumonanthe L. and G. punctata L. Methods. 5S rDNA IGS sequence was amplified using polymerase chain reaction (PCR) with a pair of primers specific for the gene coding region. The produced PCR products were fractionated by gel-electrophoresis, isolated, ligated into plasmid pUC18, cloned into E. coli, and then sequenced. Nucleotide sequences were aligned using the Muscle algorithm and analyzed in the Unipro UGENE software. Results. The intergenic spacer region of the 5S rRNA genes was cloned and sequenced for two Gentiana species of Ukrainian flora, G. pneumonanthe and G. punctata. Based on the analysis of the alignment of the IGS sequences of five Gentiana species from three sections, some features of molecular organization of IGS of 5S rRNA genes in the studied species were established. In particular, motifs typical for other angiosperm families were identified, such as conservative oligo-dT motif at the IGS 3'-end that served as a transcription termination site and AT-rich region preceding the coding region of 5S rRNA gene. However, in the region of transcription initiation, conservative GC-element in position -13 is changed to AC. Conclusions. The interspecific variation of molecular organization of 5S rDNA IGS was identified among Gentiana species that can be used to clarify the phylogenetic relationships between members of this genus.Keywords: Gentiana species, 5S rDNA intergenic spacer, molecular organization, phylogeny.

Activation of plant LTR-retrotransposons under in vitro culture stress

Retrotransposons make up a significant part of plant genome and are probably the most dynamic part of it, so they play a significant role in the generation of genetic variation. In particular, their activation can lead to structural reorganization of genome and changes in genome size, the emergence of novel genetic and phenotypic variants, as well as changes in gene expression, thus providing the raw material for adaptation and evolution. This review summarizes literature data on the activation of LTR-retrotransposons of the superfamilies Ty1/Copia and Ty3/Gypsy during in vitro culture and under various abiotic and biotic stress conditions. Their structure, classification, and significance for the organization and functioning of plant genome are reviewed. The main mechanisms of activation of LTR-retrotransposons under stress conditions are explored, including changes in DNA methylation and interaction of stress-induced transcription factors with retrotransposon promoters due to the presence of specific binding sites and other regulatory elements. The review also discusses consequences of activation of retrotransposons and control of their activity by self-inactivation mechanisms and the epigenetic regulation of genome.Keywords: retrotransposons, Ty1/Copia, Ty3/Gypsy, in vitro culture, abiotic and biotic stress.

Organization of 5S ribosomal DNA of Litchi chinensis Sonn.

Aim. 5S ribosomal DNA (5S rDNA) represents a universal model for studying the evolution of repeated sequences in eukaryotic organisms. Taking into account that this region of the genome still remains almost undescribed in species of the family Sapindaceae, we investigated the molecular organization of a repeated unit of 5S rDNA in a member of this family, Litchi chinensis. Methods. PCR amplification, cloning and sequencing of 5S rDNA. Results. It was found that the length of the repeated unit of the 5S rDNA of L. chinensis is 321 -323 bp. The level of intragenomic similarity of 5S rDNA repeats is 87.1 %. Potential external elements of the RNA polymerase III promoter, which are localized in IGS, differ from those described for members of other families of angiosperms. Conclusions. In the genome of L. chinensis, at least two classes of 5S rDNA repeats are present, which differ in the sequence of external promoter elements. Keywords: 5S rDNA, molecular evolution, Litchi chinensis, Sapindaceae.

Changes of antioxidant activity during storage of wheat grains with different colours

Aim. Evaluate the change in antioxidant activity (AOA) during one-month storage period of flour and grist obtained by grinding wheat grains with different colours: white, red and purple. Wheat grain contains components with antioxidant activity. Over time AOA may be changed that is why it is important to investigate the dynamics of AOA changes in wheat samples with different grind flour and whole grain grist. Methods. The level of antioxidant activity of wheat flour spirituous extract and grist was determined based on their capacity to neutralize stable free radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH). Results. Changes in level of antioxidant activity of cultivar «Bilyava» – white grain, «Kuyalnik» – red and «Chernozerna» – purple grain were investigated. Conclusions. Asymmetric distribution of components with antioxidant properties in wheat grains was observed. The purple grain cultivar demonstrated highest antioxidant activity the while white grain cultivar showed lowest antioxidant activity.Keywords: colored grain, antioxidant activity, flour, grist.

Effect of progesterone on the MGMT gene expression in MCF7, HEp-2 and 293 cells

Aims: to investigate the steroid hormone progesterone effect on the human MGMT gene expression at the mRNA and protein levels in cell lines with different expression patterns of the nuclear progesterone receptors and membrane receptor PGRMC1. Methods: cell culture, RNA / protein isolation, cDNA synthesis, real-time polymerase chain reaction, Western blot analysis. Results: We observe the MGMT gene upregulation by progesterone at both mRNA and protein levels. Conclusions the effect of progesterone on MGMT expression is more complex than direct regulation through the classical nuclear receptor.Keywords: O6-methylguanine-DNA methyltransferase (MGMT), progesterone, nuclear progesterone receptors (nPR), progesterone receptor membrane component 1 (PGRMC1), gene expression regulation.

Endogenous retroelemens of fish and molluscs

Aim. Analysis of scientific literature sources devoted to the study of retroelements of fish and mollusks. Results. It is shown that endogenous retroelements are widespread both among fish and mollusks. Endogenous retroviruses of fish, like exogenous ones, are also widespread, but their total number in the genomes of fish is much less than in other vertebrates. The Steamer retroelement, the presence of which is associated with the development of tumors in molluscs, can be transmitted horizontally between these invertebrates. In addition, it is able to pass into organisms of other types of aquatic animals, including vertebrates, sea urchins and corals. Conclusions. The study of the retroelements of fish and molluscs, as the most ancient organisms, makes it possible to more fully trace the stages of evolution of aquatic animals. It was shown that retroelements of fish and molluscs play an important role in the development of antiviral defense in vertebrates. The low cost of mollusks and well-developed methods of their cultivation put these invertebrates at the forefront as model systems for studying the molecular mechanisms of tumor processes in vertebrates and humans.Keywords: retroelements, fish, molluscs, tumors.

The effect of aseptic cultivation of Crambe mitridatis Juz. plants on its biochemical composition

The aim of the research was to establish efficient microclonal propagation conditions of endangered Crambe mitridatis plants in vitro and to study the possible effect of aseptic cultivation on biochemical composition (hydroxycinnamic acids, flavonoids, phenolic compounds) of plants. Methods. In vitro plant culture methods were applied. Seeds were used for aseptic culture initiation. Morphogenic potential of root, leaf and petiole explants was studied on Murashige-Skoog medium with addition of plant growth regulators. The content of biologically active compounds was measured using spectrometry in plants grown in aseptic conditions and in the greenhouse. Results. Morphogenic potential of root, leaf and petiole explants was studied and the highest regeneration frequency of plantlets was established for root explants (80 %), for petiole explants (50 %) and the lowest for leaf explants (20 %). It was found that plants cultivated in aseptic conditions have higher hydroxycinnamic acids, flavonoids and phenolic compounds compared to plants grown in vivo. Conclusions. It is advisable to multiply C. mitridatis plants in vitro via root and petiole explants. Aseptic cultivation contributes to synthesis of biologically active compounds (auxin synergists) in C. mitridatis plants.Keywords: in vitro culture, hydroxycinnamic acids, flavonoids, phenolic compounds, Crambe mіtridatis.