Vol 483, No 1 (2018)

New data on the organization of genes entirely located in the open domains for chromatin transcription and occupying only one chromosome structure (interband) were obtained. The characteristic features of these genes are the small size (on average, 1–2 kb), depletion of the replicative complex proteins in the regulatory region, and the presence of specific motifs for binding transcription factors, as compared to the genes occupying two structures (interband and gray band). The biological function of these genes is associated primarily with the processes of gene expression and RNA metabolism.

Changes in the expression level of Oct-1A, Oct-1L, Oct-1X, and Oct-1Z isoforms and CD14 surface antigen during differentiation of HL-60 monocytic cells induced in vitro by dimethyl sulfoxide were studied, and the expression level of the four Oct-1 isoforms in vivo in human monocytes was determined.

Arginine-containing peptides R3, R8, and R16 were obtained by solid-phase peptide synthesis, and their binding to nicotinic acetylcholine receptors (nAChRs) of muscle and neuronal (α7) types was studied by competitive radioligand assay with the use of ¹²⁵I-α-bungarotoxin. The resulting peptides exhibited a significantly greater binding activity with respect to the muscle-type nAChRs than to the α7 receptor. Thus, we have discovered a new class of nAChR ligands. The affinity of the synthesized oligoarginines for nAChR depended on the number of amino acid residues in the chain. The highest affinity was exhibited by the R16 peptide, which contained 16 arginine residues.

Seven different carotenoids with the number of conjugated double bonds (N) from 5 to 11 were incorporated in vitro into carotenoidless complexes LH2 of the sulfur bacterium Allochromatium vinosum strain MSU. The efficiency of their incorporation varied from 4 to 99%. The influence of N in the carotenoid molecules on the energy transfer efficiency from these pigments to bacteriochlorophyll (BChl) in the modified LH2 complexes was studied for the first time. The highest level of energy transfer was recorded for rhodopin (N = 11) and neurosporene (N = 7) (37 and 51%, respectively). In the other carotenoids, this parameter ranged from 11 to 33%. In the LH2 complexes studied, we found no direct correlation between the decrease in N in carotenoids and increase in the energy transfer efficiency from these pigments to BChl.

The site-directed mutagenesis of tomato allene oxide synthase LeAOS3 (CYP74C3) on the “F/L toggle” site resulted in a partial conversion of LeAOS3 into epoxyalcohol synthase.

The results of the study of the effect of mononuclear dinitrosyl iron complexes (DNICs) with functional sulfur-containing ligands (NO donors) on the cell viability and metabolism of human lung fibroblasts are presented, and the efficiency of their action is evaluated. It was shown that cationic DNICs increased the cell viability of fibroblasts and demonstrated the cytoprotective properties. Fluorescent analysis revealed that the DNICs compounds decrease the mitochondrial membrane potential but do not have a significant effect on the level of glutathione and reactive oxygen species in fibroblasts. It is assumed that the DNICs have the therapeutic potential for treating cardiovascular diseases.

To model human interleukin-6 (hIL-6) associated diseases, unique mice with transgenic overexpression of human IL-6 and reporter fluorescent protein EGFP in cells of macrophage-monocyte lineage were generated using loxP–Cre system. High level of hIL-6 production by macrophages and monocytes, as confirmed in vitro in primary culture of bone marrow-derived macrophages, in vivo resulted in early postnatal death in vivo, presumably, due to the effect of overexpression of hIL-6 on hematopoiesis.

The characteristics of the formation of the superoxide radical anion (\(\rm{O}_2^{\bullet-}\)) and hydrogen peroxide by xanthine oxidases isolated from microorganisms and from cow’s milk were investigated. The increase in pH led to an increase in the rate of xanthine oxidation with oxygen by both xanthine oxidases. The functioning of xanthine oxidase from milk along with the two-electron reduction of O₂ to H₂O₂ carries through the one-electron reduction of O₂ to \(\rm{O}_2^{\bullet-}\), and the rate and the fraction of generation of \(\rm{O}_2^{\bullet-}\) increased with increasing pH. Under operation of the microbial xanthine oxidase, the \(\rm{O}_2^{\bullet-}\) radical was not detected in the medium. The results suggest a difference in the operation of active centers of enzyme from different sources.

The structure of the MADS-box gene HAM31 of the sunflower (Helianthus annuus) was characterized. It is shown that the product of this gene is an ortholog of the B-class MADS transcription factor PISTILLATA (Arabidopsis thaliana). Two types of transgenic tobacco plants (Nicotiana tabacum) with the constitutive expression of the HAM31 gene in the sense and antisense orientation were obtained. The 35S::HAM31s plants formed flowers with an altered gynoecium identity, whereas 35S::HAM31as plants did not differ from the control.

The complete nucleotide sequences of 11 wild and cultivated tomato GDP-L-galactose-phosphorylase- 1 homologs (VTC2) were identified and characterized. The overall level of nucleotide variability was 9.19%. Totally 25 out of 54 cDNA SNPs were non-synonymous and resulted in amino acid substitutions. In the group of green-fruited tomato species, more SNPs were detected than in the group of red-fruited species, but the percentage of non-synonymous substitutions in red-fruited tomatoes was significantly higher (66.7% vs. 37.5%). In the translated amino acid sequences, the GDF-L-galactose-hexose-1-phosphate-guanyltransferase domain and the highly conserved HIT-motif were identified and a conserved motif specific for VTC2 of Solanoideae species was detected.