[Characterization of some thiol oxidoreductase family members].

There are no doubt about the important role of free radicals and reactive oxygen species in the processes of cell activity. The disturbances of intracellular redox processes are often accompanied with the development of such common pathologies as diabetes, myocardial infarction, neurodegeneration, broncho-pulmonary diseases, cancer, etc. To date, there are a large number of antioxidant enzymes related to different redox biology systems, the key role among them is played by enzymes belong to the thiol oxidoreductases superfamily, which consists of thioredoxin, glutaredoxin, peroxiredoxin, protein disulfidizomeraz, glutathione peroxidase families, and a number of other proteins. In addition to the antioxidant function, thiol oxidoreductases display the ability to recycle of hydroperoxide to form specific disulfide bonds within and between proteins that significantly extends the range of their functionality. Therefore, biochemical characterization and elucidation of functional mechanisms of the superfamily proteins is a highly actual problem of redox biology.

[Biosyinthesis and mechanism of selenocysteine incorporation into synthesized proteins].

Universal genetic code provides the ability to encode only twenty "canonical" amino acids, whereas the twenty first amino acid--selenocysteine (Sec), is encoded by one of three well-known stop codon (UGA). In terms of molecular biology, selenocysteine is of exceptional interest, the mechanism of its incorporation into synthesized polypeptide chains is very different from that of the other typical 20 amino acids. This process involves some cis- and trans-active factors, such as the SECIS element (Selenocystein insertion sequence), a structure located in the 3'-untranslated region of eukaryotic mRNA, and in the open reading frame immediately after the UGA-selenocysteine codon in bacteria, which, in turn, leads to differences in the mechanism of selenocysteine incorporation in these domains of life. The trans-factors include Sec-tRNA([Ser]Sec) that has a unique system of biosynthesis, Sec-specific elongation factor EFsec and SBP2--Sec binding protein. Thus, for realization of the selenocysteine incorporation process during translation a large number of additional molecules must be synthesized in the cell, this fact makes the selenocysteine containing proteins rather "expensive" and emphasizes their crucial role in metabolism.

[Detection of c-fos expression in animal brain in a pilocarpine model of temporal lobe epilepsy].

The dynamics of the involvement of different brain structures in a pathological process is very important for decoding the mechanisms of temporal lobe epilepsy. In this work, the experimental model of temporal lobe epilepsy induced by lithium chloride and pilocarpine was used. The method of immunochemical detection of the immediate early gene c-fos was used as an indicator of functioning neurons in the brain. The c-fos expression was determined at different time points (30, 60 and 90 min) after the pilocarpine injection. An increase in the c-fos expression was observed in neuronal populations during the development of the status epilepticus, the time and degree of involvement of different brain structures being different. The expression of c-fos was first observed in the piriform cortex, the olfactory tubercle, thalamic nuclei, lateral habenular nuclei, and the caudate putamen. Then the hippocampus, the septal formation, the amygdala, and basal ganglia were involved in the activation process. In the hypothalamic areas, c-fos expression was observed latest. These data contribute to understanding the mechanisms of temporal lobe epilepsy and searching for the ways of its therapy.