Vol 43, No 4 (2016)

Transgenic clones of mouse embryonic stem cells of the R1 line were received by transfection of plasmid linear vectors. The changes in the transgene structure during its integration into the genome of the target cells were investigated. Displacements were found on the flanks of the integrated transgene. It was found that multicopy tandem structures are formed in head–tail orientation at the transgene integration. It was noted that the number of copies of the integrated transgenes varies considerably, but the introduction of DNA fragments isolated from the nuclear envelopes into the flanks of the transgene normalizes the number of its copies.

It was established that the biomass of fungal mycelium decreased by 30–50% during passage through the intestine of the Aporrectodea caliginosa and Lumbricus terrestris earthworms, while its content in empty intestines was 40–60% less than in the soil. It was found that the amount of mycelium increases again in three-day-old coprolites due to the rapid growth of the species. It was demonstrated that the physiological activity of fungi (estimated according to the time of the appearance of colonies on the medium and probability of propagation) is lower in the intestine content, digestive tract, and fresh excrement of the worms than in the soil. It was noted that the activity and diversity of organic substrates (utilized by fungi), as well as proteolytic activity is lower in fungal isolates from the intestine than from the soil. It was registered that the death of a part of the fungi occurs in the worm intestine, while the physiological state changes in the animals withstanding the effect of the digestive medium.

Primary plant successions on volcanic deposits of the Tolbachinskii Dol Plateau (Central Kamchatka) were studied. The main factors determining the succession rate were revealed. The peculiarities of plant successions on lava flows and ash–scoria deposits differed significantly. Some common mechanisms for all volcanic regions of the world were revealed. The leading factors of plant succession on lava flows were the type of lava surface, the texture of lava, and the fine tephra accumulation rate. The main factors determining plant succession on ash–scoria deposits were wind and water erosion and the distance to the seed sources. The time of formation of a secondary permanent larch (Larix cajanderi Mayr.) forest should take about 1500–2000 years on lava flows and up to 1000 years (but not less than 300–500 years) on ash–scoria plains.

The orosensory food testing behavior in fish was studied using the nine-spined stickleback Pungitius pungitius as an example. The patterns of the chronology of manipulations performed by fish in testing food objects were identified. The existence of two stereotypical patterns of feeding behavior was confirmed, and their new characteristics were obtained. The relationship between the responsiveness to food and the predisposition of fish to feeding was revealed.

Based on the structure of the control region (D-loop) of mitochondrial DNA, the genetic diversity of moose of West Siberia was evaluated and their placement within the structure of current species population was determined. It was noted that the values of genetic diversity exceed the values of analogous indices obtained for western groups of the species. Three haplogroups were identified in the population structure: European–Ural, West Siberian, and American.

The general patterns of the effect of cuttings on the habitat structure, abundance, territorial distribution, and specific ecological features of 11 small mammalian species are analyzed based on long-term studies (1958–2013) covering the overall area of eastern Fennoscandia. The responses to concentrated cuttings common for most of the examined species include a decrease in total population size, transition to an arrhythmic population dynamics with drastic short-term rises and deep long depressions, formation of unstable mosaic spatial distribution, disturbances of the reproduction rates, and a decrease in reproduction intensity.

The dependence of shell growth in length and height during ontogeny has been studied in the pearl mussel Margaritifera margaritifera inhabiting the Nemina River (basin of Lake Onega, Karelia). It has been shown that the population is heterogenous based on the height-to-length ratio. It has been found that during ontogeny M. margaritifera from the studied population undergoes a constant change in the relative growth of the shell leading to either lengthening or rounding of the shell.

It has been found that the species composition of parasites infesting the Chinese sleeper Perccottus glenii in water bodies from the nonnative part of its range is more depleted. Here, the phylogenetic distances between parasites exceed those in the native part of the range. It has been revealed that parasitological differences between P. glenii populations from the nonnative and native parts of the range, as well as between populations inside the nonnative part, have similar composition and abundance of the host-specific and euryxenous components in the parasitic fauna. It has been shown that these differences are determined by the genesis of sites from which P. glenii is introduced, as well as the local conditions of the recipient water bodies.