Open Access Open Access  Restricted Access Access granted  Restricted Access Subscription or Fee Access

Vol 11, No 3 (2013)

Articles
The intron-containing transcript: an evolutionarily conserved characteristic of genes orthologous to nxf1 (Nuclear eXport Factor 1)
Mamon L.A., Kliver S.F., Prosovskaya A.O., Ginanova V.R., Golubkova Y.V.
Abstract
Background. The function of nxf1 (Nuclear eXport Factor 1) gene is the nuclear-cytoplasmic transport of most mRNAs. A characteristic feature of nxf1 genes in animals belonging to different taxonomic groups is the existence of an alternative transcript with a homologous intron called a cassette intron. Materials and methods. The following databases were used: Genbank (http://www.ncbi.nlm.nih.gov/); Flybase (http://flybase.org/); UCSC Genome (http://genome.ucsc.edu). To build the secondary structures of nucleotide sequences we used the UNAFold v3.8 suite (http://mfold.rna.albany.edu/). Results. The existence of evolutionarily conserved sequences of intron 10–11 in nxf1 genes in vertebrates, and the presence of two poly(A) sequences of intron 5–6 in nxf1 genes of Drosophilidae, may be adaptive. The nxf1 cassette introns form characteristic secondary structures. Conclusion. The paper discusses the possible functional significance of the intron-retaining transcripts of nxf1 genes.
Ecological genetics. 2013;11(3):3-13
views
Genetic control of chlorophyll metabolism
Chekunova E.M.
Abstract
Chlorophylls (Chl) are unique tetrapyrrole molecules, essential not only for photosynthesizing organisms but for the whole Biosphere. Chlorophyll biosynthesis is closely connected with plant cell morphogenesis and photosynthetic reactions - storage and transferring of light energy. Pigment mutants of plant and microorganisms are successfully used for investigation of Chl biosynthesis and degradation pathways. The genetic approaches appeared to be very productive for identification of the genes, encoding the enzymes of Chl metabolism and for elucidation of the mechanisms there regulating. History, recent findings and evolution of genetic determination of Chl formation processes are presented in this review.
Ecological genetics. 2013;11(3):14-36
views
Аnalysis of the genetic variability of populations of land snail Сhondrula tridens Müll. (Gastropoda, Pulmonata) RAPD and ISSR markers
Snegin E.A.
Abstract
Background. This article is about evolutionary processes in populations of small mobile species in the urbanized landscape. Materials and methods. Based of the polymerase chain reaction, using RAPD and ISSR DNA markers the genetic structure of populations of model species of terrestrial mollusks Сhondrula tridens Müll., living in Mid-Russian Upland, has been analyzed. Results. Interpretation of the obtained DNA-patterns is presented. Polymorphic and monomorphic amplicons are identified. The level of genetic variability of population is defined. The factors influencing formation population of gen pool of the given species in the conditions of the urbanized landscape are revealed. Conclusion. The structure of population’s distribution and the state population gene pools of Ch. tridens in the urbanized landscape were determined.
Ecological genetics. 2013;11(3):37-47
views
Enzyme polymorphism of antioxidant system in chronically irradiated Scots pine populations
Volkova P.Y., Geraskin S.A.
Abstract
Background. The Chernobyl accident caused dramatic and long-term increases in ambient radiation doses to many forest environments. Sites still exist in the Bryansk region of Russia, 25 years after the Chernobyl accident, where radioactive contamination significantly exceeds background. There is growing evidence that effects of chronic radiation exposure lead to population-level impacts. Isozymes polymorphism assessment is thought to be promising since it sensitive enough, may integrate the impacts of harmful agents in the environment, and provide meaningful information on biological damage The aims of this study were to examine whether Scots pine trees have experienced stress in areas with relatively low levels of radioactive contamination and, if so, to quantify such an impact.Materials and methods. Scots pine (Pinus sylvestris L.), the dominant tree species in North Eurasia boreal forests, was chosen as a test organism for an assessment of the possible effects from the radioactive contamination. Four study sites were chosen in the most contaminated areas of the Bryansk region of Russia. This area was significantly contaminated by Chernobyl fallout with an initial 137Cs ground deposition level more than 1 MBq/m 2 in some locations (Ramzaev et al., 2008). Sites are uniform in climate and the physical and chemical properties of soils, forest stand is homogeneous, and pine trees occupy a large part of phytocenosis. Dose rates at the study sites ranged from 0.37 to 1.21 μGy/h, compared to 0.10 μGy/h at control site. Pine cones were collected in December of 2009–2010. Specific activities of radionuclides in soil samples were measured, and doses to the pine trees’ generative organs were estimated. Antioxidant enzymes polymorphism (superoxide dismutase (SOD, KF 1.15.1.1), glutathione reductase (GR, KF 1.6.4.2), and glutathione peroxidase (GPX, KF 1.11.4.2)) was investigated by vertical electrophoresis.Results. The study sites did not differ substantially in soil properties, or chemical content of soil or pine cones (Geras'kin et al., 2011; Geras'kin et al, 2008). The main contribution to the radioactive contamination was from 137Cs with activity concentrations at the contaminated sites (averaged through 0–15 cm soil layer) ranging from 2.4 to 56.3 kBq/kg of soil. These activity concentrations exceed those at the referent site by factors of 47–1081 (Geras'kin et al., 2011). Annual absorbed doses rates changes from 7.0 to 130 mGy/year compared to 0.14 mGy/year at reference site. The average frequency of mutations in three enzymes significantly (r = 99 %, p <0.01) increases with increasing absorbed dose by generative plant organs. Indices of phenotypic diversity in the populations studied are significantly different from the control. Proportion of rare morphs dramatically increases in populations inhabiting areas contaminated with radionuclides, which is associated with the emergence of new alleles in several enzyme systems (null alleles, allele 0.80 in the GPX-1 and 0.95 in the GPX-2). The observed and expected heterozygosity in affected populations increase along with the level of contamination sites (r = 99 %, p <0.01).Conclusions. These data show that chronic, low level radiation exposure (7–130 mGy/year) results in an increase in frequency of mutations in the endosperm and the seed embryos and modify the genetic structure of Scots pine populations. These data suggest that a high level of mutations occurs in the progeny of these pine populations and that their diversity is conditioned by radiation exposure. Thus, in spite of their low values, dose rate observed can be considered as a factor capable of modifying the genetic structure of populations.
Ecological genetics. 2013;11(3):48-62
views
LIM-kinase 1 in regulation of cognitive and locomotor functions of Drosophila melanogaster
Kaminskaya A.N., Medvedeva A.V.
Abstract
Background: LIM-kinase 1 is the key enzyme of actin remodeling which is necessary for synaptic plasticity during learning and memory formation. Deletion of limk1 leads to the development of Williams syndrome, accompanied by cognitive impairment and motor dysfunction, which refers to cytoskeleton diseases – cofilinopatia. Cofilinopatias are characterized by the formation of cofilin-actin complexes in neurons that disrupt vesicular transport and identify the early stages of dementia. Conclusion: In the present article, we briefly reviewed data about role of LIMK1 function in communicative sound production during courtship behavior, learning acquisition and memory formation.
Ecological genetics. 2013;11(3):63-78
views
Classification of variability forms based on phenotype determining factors: Traditional views and their revision
Tikhodeyev O.N.
Abstract
Phenotype determining factors are critically analyzed. It is shown that these factors are four: initial hereditary material of an organism, ontogenetic regularities, directional environmental influences, and molecular stochastics. As a result, four separate forms of variability (genotypic, ontogenetic, environmental and fluctuational) are distinguished. Delineation of these phenomena and their place in modern views on variability classification are discussed.
Ecological genetics. 2013;11(3):79-92
views

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies