Effect of histidine­containing dipeptide carnosine on passive avoidance response in normal conditions and under the influence of acute hypobaric hypoxia was analyzed using a three­compartment apparatus that consisted of a light compartment, a dark dangerous compartment in which foot shock was delivered, and a dark safe compartment where the rats were never shocked. The experiment revealed, that carnosine normalized physiological parameters, disrupted by acute hypobaric hypoxia, and increased preference of the safe compartment in both intact rats and hypoxia­treated animals.

High doses of valproic acid repress histone deacetylases and modify functioning of many genes. After its prenatal injection in offspring of laboratory animals the fetal valproate syndrome occurs considered as a model of autism spectrum disorders. Our review describes features of brain condition and activity during fetal valproate syndrome at different levels, from molecular and cellular to behavioral. Special attention is paid to the social interactions, the most relevant manifestations of autistic disorder. Both literature analysis and results of the authors‘ research are presented.

This review analyses the current views on the spatial organization of the eukaryotic genome and functional compartmentalization of the eukaryotic cell nucleus. The idea that folded genome constitutes a platform for the compartmentalization of the cell nucleus is considered and justified. Different mechanisms of mutual positioning of remote genomic elements and mechanisms directing assembly of functional compartments within the cell nucleus are discussed. In particular, the role of the depletion attraction force originating under conditions of macromolecular crowding is highlighted. In the last section of the review the model is discussed that postulate a crucial role of stochastic processes in establishing of the so­called functional architecture of the eukaryotic genome as well as in assembly of functional nuclear compartments.

Endogenous and exogenous agents generate tens of thousands lesions in the DNA of every cell daily. Maintenance of the DNA integrity by repair systems is crucial for genome functioning. Eukaryotic nuclear DNA is tightly packaged into chromatin. DNA repair should be considered in these conditions. Recent studies lead to a revision of the historical “access — repair — restore” paradigm of the DNA damage response indicating the chromatin structure as an active player in the process regulating localization, pathway choice, enzyme activity and restoration of the repaired locus function.

The expression of SERPINA1 gene in prostate prostate (DU145, PC-3 and LNCaP) and human liver (HepG2) tumor cell lines was studied. Alpha1-antitrypsin (AAT) level in the whole cell extracts, secretomes, subcellular fractions and SERPINA1 mRNA level in the corresponding cells were detected. Discordance between expression at these two levels in PC-3 and LNCaP lines was revealed. A new 37 KDa AAT N-terminus truncated isoform was detected in the nuclear extracts of some prostate tumor cell lines. The mechanism of 37 KDa AAT isoform intracellular retention was proposed. Two polyadenylation sites in the 3-untranslated region of SERPINA1 transcripts were identified. A SERPINA1 gene 3-untranslated region influence on AAT translation has been discussed.

Among biological macromolecules imported into the eukaryotic cells mitochondria, there are proteins and ribonucleic acids. Protein import into mitochondria is a universal process, and its mechanisms are currently well described. RNA import into mitochondria, on the contrary, is known only for several eukaryotic species, and the mechanisms of this process are largely species-specific. In this review, we summarize existing data about RNA import into mitochondria of human cells and discuss the possibilities of its implication for the gene therapy of mitochondrial diseases.

Miniaturization is a widespread trend in animal evolution and one of the principal directions of evolution in insects. Body size, especially extremely small, largely determines the morphology, physiology, and biology of animals. Miniaturization leads to considerable reorganizations of structure in insects, affecting almost all organs and tissues. In the smallest insects, comparable in size to unicellular organisms, modifications arise not only at the level of organs, but also at the cellular level. Miniaturization is accompanied by allometric changes in many organ systems. The consequences of miniaturization displayed by different insect taxa include both common and unique changes.

The hydroplasmic stream system and the conformities of hydroplasm volumes redistribution at three mode of feeding (proximal, distal, uniform) in uniradiate colonies Dynamena pumila (L., 1758) (Hydrozoa, Sertulariidae) were studied. The hydroplasmic flows in the colonies are not synchronized and the net flow is represented by a vast variety of unique variations. The period of flow-through varied very widely and had an extremely high coefficient of variation. The functioning of the distribution system is realized on the hydraulic basis in absence of general colonial processes of integration and self-regulation, and its efficiency does not depend on the level of complexity of the colonial structure.

One of the major problems of molecular biology is studying the underlying principles of chromatin work. This problem is associated with understanding the processes of epigenetic regulation of gene expression, DNA repair and heredity mechanisms. The basic unit of chromatin organization is nucleosome, which consists of DNA and histone proteins. For a long time nucleosome structure obtained by X-ray crystallography was considered as the ultimate and main conformational state of nucleosomes, but recent experimental data indicates that chromatin functions depends on conformation state of nucleosomes. Nevertheless, there is no detailed understanding of the conformational dynamics of nucleosomes at the atomistic level. In this paper, we have addressed this problem using molecular dynamics simulations of nucleosome in explicit solvent. We have investigated the dynamics of nucleosome on the 500 ns time interval, produced covariance analysis of the trajectory and derived the collective motions, studied the distribution of water molecules in the system and assumed the role of internal water.