Human chromosome 3P regions of putative tumor-suppressor genes in renal, breast, and ovarian carcinomas

Allelic imbalances (AI) of polymorphic markers at the short arm of chromosome 3 (3p) were mapped using DNA samples of renal cell carcinoma (RCC, 80 cases), breast carcinoma (BC, 95 cases), and epithelial ovarian cancer (EOC, 50 cases) at the same dense panel of markers (up to 24 loci). Six regions with the increased AI frequency (versus the average values determined for all the analyzed 3p markers) at RCC, BC or EOC were found in 3p chromosome. Four 3p regions presumably contain suppressor genes of tumor growth (TSG) observed in the epithelial tumors of various types. Region between D3S2409 and D3S3667 markers in the 3q21.31 region was identified in this study for the first time. The AI peak in D3S2409-D3S3667 region was statistically significant (P < 0.001, according to Fisher) when representative sample of 95 BC patients was analyzed. The data on increased frequency of polymorphic marker allele amplification suggest that the D3S2409-D3S3667 region contains both putative TSG and protooncogenes.     

Description of three microsatellite loci of the Baikal omul Coregonus migratorius (Georgi)

Three new microsatellite loci found for the Baikal omul Coregonus migratorius (Georgi) are described.     

Valentin Sergeevich Kirpichnikov: on the 100th anniversary of his birth (1908-1991)

Valentin Sergeevich Kirpichnikov is an outstanding Russian biologist, geneticist, and evolutionist. In his work, the true interest to the theory of evolution was harmoniously combined with long-term successful research into fish genetics and breeding. In 1987, Kirpichnikov published a fundamental treatise entitled "Fish Genetics and Breeding," which was immediately translated into English, German, and Japanese and still remains the most comprehensive handbook in this field. The authority of Kirpichnikov was confirmed by his election to the International Association of Aquaculture and an expert of the leading international organization on food and agriculture, FAO, with the United Nations. During the hard years in the history of Soviet biology, the courage and fidelity to the principles in defending the scientific biology and opposing Lysenko's obscurantism won Valentin Sergeevich the deserved name of a "knight of science". His mode of speech at the seminars and in discussions was unhurried, calm, and fitting. Yet especially important moments supplemented his baritone with hard metal modulations, which revealed the concealed passion and conviction in the defended truth.     

Molecular motility of a fluorescent probe in binding sites of albumin molecules

The molecular mobility of the fluorescent probe, N-(carboxymethyl)imide of 4-(dimethylamino)naphthalic acid (K-35) in three types of binding sites on a human serum albumin (HSA) molecule has been studied. The time-resolved decay of K-35 polarized fluorescence in HSA has been studied and it has been shown that probe molecules bound to different sites have different fluorescence decay time, which poses problems in the interpretation of polarization decay. However, it has been found that, in the case of rather slow thermal rotation of the probe, the decay of each of vertical and horizontal polarized fluorescence components can be approximated by three exponentials corresponding to three types of binding sites. The mobility of the probe in different sites was estimated. The mobility was different but hindered by tens of times in all sites as compared with the rotation of K-35 in water. The slowest motion occurred in the sites of the first type localized in the region of the well known first drug-binding site: here the rotational correlation was close to 72 ns or more. In the sites of the second type, the time was about 40 ns, and in the sites of the third type, the time was about 10 ns. It was found that the higher the rotation rate, the higher the fluorescence quenching rate. Probably, it is this motion that is responsible for different fluorescence decay times in different HSA sites.     

Effect of chemical chaperones on properties of lysozyme and the reaction center protein from Rhodobacter sphaeroides

The influence of three chemical chaperones: glycerol, 4-hexylresorcinol, and 5-methylresorcinol on the structure, equilibrium fluctuations, and the functional activity of the hydrophilic enzyme lysozyme and the transmembrane reaction center (RC) protein from Rb. sphaeroides in a broad range of concentrations has been studied. Selected chemical chaperones are strongly different by the structure and action on hydrophilic and membrane proteins. The influence of the chemical chaperones (except methylresorcinol) on the structure, dynamics, and functional properties of lysozyme and RC protein are well described within the frames of extended models of preferential hydration and preferential interaction of protein with a chemical chaperone. A molecule of hexylresorcinol consists of a hydrophobic (alkyl radical) and a hydrophilic (aromatic nuclus) moieties. This fact provides additional regulation of functional activity of lysozyme and RC by hexylresorcinol. The influence of methylresorcinol on proteins differs from that of glycerol and hexylresorcinol. Methylresorcinol interacts with the surface of lysozyme directly, not via water hydrogen bonds. This leads to a decrease in denaturation temperature T(d), and an increase in the amplitude of equilibrium fluctuation, which allows him to be a powerful activator. Methylresorcinol interacts with the membrane RC protein only by the condensation of hydration water, which is negligible in the case of methylresorcinol. Therefore, methylresorcinol does not effect the functional properties of the RC protein. It was concluded that various chaperones at one and the same concentration and chaperones at different concentrations form diverse 3D structures of proteins, which differ by dynamic and functional characteristics.     

The impact of the high dose-refuge strategy on the Bt-crop yield. Mathematical simulations

A mathematical model is presented, which describes interactions between Bt-plants and pests in terms of the plant growth rate, plant annual reseeding, consumption of plant biomass by pests, the action of Bt toxins, and the emergence of Bt-resistant insects. It has been shown that the migration of Bt-susceptible insects affects the Bt-crop yield dynamics and provides the exclusion of Bt-resistant pests if the migration exceeds the threshold value.     

Kinetic chemiluminescence as a method for the study of free radical reactions

The review gives concepts of analysis of kinetics of complex reactions with the participation of free-radicals. The concepts are based on the comparison of the kinetic curves of the chemiluminescent reactions in the presence of a physical enhancer coumarin C-525 with the simulated kinetic functions. This method was applied to the investigation of the mechanism of a branched-chain reaction of lipid peroxidation in biological and phospholipid membranes as well as to the effect of antioxidants and determination of their activities. It was also used for studying the reaction of the formation of free radicals in the complex of cytochrome c with cardiolipin. This reaction plays a key role in the initiation of apoptosis.     

Noninvasive estimation of the oxygen state of experimental tumor by diffuse optical spectroscopy

The potentialities of diffuse optical spectroscopy for the noninvasive estimation of the oxygen state of experimental tumors have been demonstrated. The distribution of total, oxygenated and deoxygenated hemoglobin, as well as the level oxygen saturation of blood have been shown using two tumor models differing in the histological structure and functional characteristics. The results obtained by the optical method have been verified by immunohistochemical examination of tissue specimens with the exogenous hypoxia marker pimonidazole.     

Comparative cytogenetic analysis of hexaploid Avena L. species

Using C-banding method and in situ hybridization with the 45S and 5S rRNA gene probes, six hexaploid species of the genus Avena L. with the ACD genome constitution were studied to reveal evolutionary karyotypic changes. Similarity in the C-banding patterns of chromosomal and in the patterns of distribution of the rRNA gene families suggests a common origin of all hexaploid species. Avena fatua is characterized by the broadest intraspecific variation of the karyotype; this species displays chromosomal variants typical of other hexaploid species of Avena. For instance, a translocation with the involvement of chromosome 5C marking A. occidentalis was discovered in many A. fatua accessions, whereas in other representatives of this species this chromosome is highly similar to the chromosome of A. sterilis. Only A. fatua and A. sativa show slight changes in the morphology and in the C-banding pattern of chromosome 2C. These results can be explained either by a hybrid origin of A. fatua or by the fact that this species is an intermediate evolutionary form of hexaploid oats. The 7C-17 translocation was identified in all studied accessions of wild and weedy species (A. sterilis, A. fatua, A. ludoviciana, and A. occidentalis) and in most A. sativa cultivars, but it was absent in A. byzantina and in two accessions of A. sativa. The origin and evolution of the Avena hexaploid species are discussed in context of the results.     

New allele of the COCHLEATA gene in pea Pisum sativum L

Analysis with the polymerase chain reaction showed that the Khlorofill-4 pea Pisum sativum chlorophyll-deficient mutant with reduced stipules has an altered structure of the COCHLEATA (COCH) gene, carrying a new mutant COCH allele. The phenotype of the mutant was described in comparison with another form having reduced stipules (stipules reduced) and the control. Leaves of the coch mutant are smaller and have other proportions than in the control; stipules are absent from leaves of the first nodes and are narrow, bandlike, or spoonlike at later ontogenetic stages. It was concluded that the cell number in the stipule epidermis is reduced in the st and coch mutants compared to the wild type.