Dynamics of folliculogenesis of sexually mature and neonatal ovarian tissue under conditions of long-term heterotopical transplantation

In this work, a comparative analysis of dynamics of morphological development and endocrine function of transplants of sexually mature and neonatal ovarian tissue was performed under conditions of bilateral ovariectomy of animals-recipients. It has been established that at transplantation of the sexually mature ovarian tissue there were observed all stages of folliculogenesis and preservation of endocrine function at long-term observation (up to 100 days). At transplantation of neonatal ovarian tissue there was revealed a pathological picture of its development: hyperplasia of stromal structure and formation of cysts and cystomae. Follicles of different degree of maturity were revealed in 30 % of animals at the 30th day of observation. A significant increase of concentration of sex hormones as compared with ovariectomied animals has been shown only at early stages after implantation (30 days).     

Interaction of human creatine phosphokinase isoenzymes with rabbit antibodies and their Fab-fragments

The interaction of human creatine phosphokinase isoenzymes with rabbit antibodies and their Fab has been studied. It has been shown that Fab of the antibodies against MM or BB isoenzymes preserve high specificity of intact antibodies and the ability to inhibit creatine kinase isoenzymes. Differences between antibodies and their Fab have been found to exist with respect to the kinetics of binding with homologous isoenzymes: the rate of the complex formation for Fab is significantly higher. The interaction of creatine kinase isoenzymes with intact antibodies and their Fab is not affected by the addition of creatine kinase substrates. The antibodies against MM and BB isoenzymes have been used to study the individual properties of each subunit of the M- and B-type in a hybrid dimer MB. It has been shown that such properties of these subunits as the Michaelis constants, pH dependence and inhibition by homologous antibodies are identical to those of non-hybrid MM and BB isoenzymes, respectively.     

Assessment of the composition and structure of covalent complexes of superoxide dismutase with aldehyde dextran by analytical ultracentrifugation]

Superoxide dismutase was covalently coupled wih aldehyde dextran, a polymeric carrier of molecular mass of 70 kDa. Modification produced an increase in the enzyme thermostability. Modified preparations retained a high specific activity. The composition of the thus obtained conjugates was analyzed by the ultracentrifugation and diffusion methods. The protein induced the destruction of aldehyde dextran, the enzyme being modified by its fragments. The presence of aldehyde dextran excess in the incubation medium promoted superoxide dismutase dissociation into individual subunits. At the enzyme/carrier ratio of 1:02 modification occurred as covalent coupling of the biocatalyst subunits and its one-point modification.     

Disruption of shape complementarity in the ribosomal protein L1–RNA contact region does not hinder specific recognition of the RNA target site

The formation of a specific and stable complex between two (macro)molecules implies complementary contact surface regions. We used ribosomal protein L1, which specifically binds a target site on 23S rRNA, to study the influence of surface modifications on the protein?RNA affinity. The threonine residue in the universally conserved triad Thr?Met?Gly significant for RNA recognition and binding was substituted by phenylalanine, valine and alanine, respectively. The crystal structure of the mutant Thr217Val of the isolated domain I of L1 from Thermus thermophilus (TthL1) was determined. This structure and that of two other mutants, which had been determined earlier, were analysed and compared with the structure of the wild type L1 proteins. The influence of structural changes in the mutant L1 proteins on their affinity for the specific 23S rRNA fragment was tested by kinetic experiments using surface plasmon resonance (SPR) biosensor analysis. Association rate constants undergo minor changes, whereas dissociation rate constants displayed significantly higher values in comparison with that for the wild type protein. The analysed L1 mutants recognize the specific RNA target site, but the mutant L1?23S rRNA complexes are less stable compared to the wild type complexes. Copyright © 2010 John Wiley & Sons, Ltd.     

Intercalating Insert into Internucleotide Linkages as Way for Stabilization and Detection of of Short DNA Duplexes

Abstract

Simple and convenient method for stabilization and detection of duplexes of short oligonucleotides with DNA was developed. This method is based on use of oligonucleotides containing inercalating insert in internucleotide linkage. The linker is so long that dye can intercalate only into the same stacking contact. Additionally the method allows to introduce into oligonucleotide as one intercalator as well as several identical or different intercalating dye.     

Morphohistochemical analysis of secretory elements of the olfactory epithelium of marine fish

Morphohistochemical characteristics of various secretory elements of the olfactory lining have been analysed in sea fishes. In the investigation epithelium of Chondrostei and Teleostei has been used. For secrete formation, besides supporting cells, specialized secretory elements take part; among them cells of the I, II and III types can be revealed, as well as tubular and alveolar epithelial glands in some species of fishes. The secretory elements of the olfactory lining of the sea fishes produce substances of various chemical nature specific for the given type of formations and not depending on species-specific and ecological specialization. Essential species-specific differences are revealed in distribution, combinations, size and amount of the secretory elements per one unit of the olfactory lining surface. The analysis of these parameters in macro-, medio- and microsmatics, in fishes of various ecology and different systemic position, also demonstrates their differentiation.     

Methylation Levels of SLC23A2 and NCOR2 Genes Correlate with Spinal Muscular Atrophy Severity

Spinal muscular atrophy (SMA) is a monogenic neurodegenerative disorder subdivided into four different types. Whole genome methylation analysis revealed 40 CpG sites associated with genes that are significantly differentially methylated between SMA patients and healthy individuals of the same age. To investigate the contribution of methylation changes to SMA severity, we compared the methylation level of found CpG sites, designed as “targets”, as well as the nearest CpG sites in regulatory regions of ARHGAP22, CDK2AP1, CHML, NCOR2, SLC23A2 and RPL9 in three groups of SMA patients. Of notable interest, compared to type I SMA male patients, the methylation level of a target CpG site and one nearby CpG site belonging to the 5’UTR of SLC23A2 were significantly hypomethylated 19–22% in type III-IV patients. In contrast to type I SMA male patients, type III-IV patients demonstrated a 16% decrease in the methylation levels of a target CpG site, belonging to the 5’UTR of NCOR2. To conclude, this study validates the data of our previous study and confirms significant methylation changes in the SLC23A2 and NCOR2 regulatory regions correlates with SMA severity.