Chromosome C-banding patterns in isolated population of the grasshopper Podisma pedesis (L.) (Orthoptera,Acrididae) from the Altai Mts

The C-banding patterns in the embryo chromosomes of the grasshopper Podisma pedestris (L.) from the Altai Mts are reported. The additional second C-heterochromatic arms in at least five pairs of autosomes and in the X-chromosome were revealed. The paracentromeric, interstitial, and telomeric C-bands were observed. The studied population of P. pedestris shows some differences in the distribution and amount of the heterochromatin in comparison with European populations.     

The effect of pre-eclamptic umbilical cord serum on fibroblast division in culture

Edema, proteinuria, hypertension (EPH-gestosis), most commonly termed as pre-eclampsia, is the most common pregnancy-associated pathological syndrome. It is accompanied by a thorough remodelling of extracellular matrix in the umbilical cord tissues. It is commonly known that the presence of serum in culture medium strongly stimulates many functions of cells cultured in vitro. It was decided to check how the pre-eclamptic serum affects the fibroblast division in culture. Ki-67 is a protein present in proliferating cells and can be detected during all phases of the cell cycle (G1, S, G2/M) but not in resting (G0) cells. PCNA (proliferating cell nuclear antigen) is an intranuclear polypeptide whose synthesis rate is at its maximum during the S-phase of the cell cycle. The expression of Ki-67 and PCNA was measured by immunocytochemical methods and biosynthesis of DNA was evaluated by [14C]-thymidine incorporation. The activity of pre-eclamptic umbilical cord serum (UC-serum) was found to be distinctly lower in comparison to control one. The expression of Ki and PCNA in fibroblast cultures treated with pre-eclamptic serum was also distinctly lower. Also the incorporation of [14C]-thymidine to DNA was lower than in the cultures treated with control UC-serum. It may by concluded that pre-eclampsia reduces the mitogenic activity of the umbilical cord serum.     

The influence of various modified nucleotides placed as 3'-dangling end on thermal stability of RNA duplexes

The ribonucleic acids (RNA) form highly folded structures, which behind the helical fragments contain several secondary and tertiary structural motives. All of them have an influence on thermodynamic stability of the RNA. The 5'- and 3'-dangling ends are one of those structural motives, which effect stability of the adjacent helixes. In this paper, we described the influence of 14 different modified nucleotides, placed as 3'-dangling ends, on thermal stability of the RNA duplexes. Collected data demonstrate that: (i) 5-substituents of the uridine have an impact on the 3'-dangling end effect and the largest changes were observed for 5-chloro, bromo and methyl substituents; (ii) position of the methyl group within the uracil residue affect the thermal stability of the duplex; (iii) increasing a size of the heterocycle base placed as the 3'-terminal unpaired nucleotide enhances stabilization of duplexes.     

Evaluation of genetic diversity and uniformity of head cabbage DH lines by the use of RAPD markers

DH lines derived from cabbage cvs. Kamienna G?owa, S?awa z Enkhuizen and Langendijker, representing R1 generation, were analysed by the use of RAPD markers for their diversity and uniformity. For the evaluation of genetic diversity, eight primers yielding informative bands were used. Of the total of 83 RAPD bands scored in this study, 16.9% were polymorphic between a set of 13 DH lines. The similarity of the DH lines, estimated by Jaccard's coefficient, was depicted in the UPGMA dendrogram. Fourteen generated informative RAPD bands allowed the identification of DH lines developed from each cultivar. The evaluation of the uniformity for six closely related DH lines was possible by the use of three primers which generate one or two polymorphic bands. The lack of differences among ten plants of the five investigated DH lines manifested their uniformity. One line showed intraline polymorphism with two RAPD primers. The occurrence of the differences at the molecular level among ten plants indicated that their parental R0 plant was probably obtained from somatic cells, not by androgenesis.     

Isozymes in Aegilops kotschyi and Ae. biuncialis x Secale cereale hybrids and Ae. kotschyi x S. cereale amphiploids in relation to their parents

Seven enzymatic systems in F1 Aegilops kotschyi and Ae. biuncialis x Secale cereale hybrids, Aegilops kotschyi x S. cereale amphiploids and their parental species (Ae. kotschyi, Ae. biuncialis and S. cereale) were analysed by starch and polyacrylamide gel electrophoresis. Five of them (phosphoglucose isomerase, glutamic oxalacetic transaminase, esterase, acid phosphatase, and diaphorase) were polymorphic and two (malic dehydrogenase and superoxide dismutase) were monomorphic. Several isophorms of phosphoclucose isomerase, esterase, acid phosphatase, and diaphorase were detected in some hybrids and amphiploids, but absent in the parents. The role of regulators, translocations and recombination is discussed in relation to the origin of these new isophorms. Some parental isozymes were absent both in hybrids and amphiploids, probably as a result of the suppression of structural genes in new combinations of the three genomes.     

Seed-expressed fluorescent proteins as versatile tools for easy (co)transformation and high-throughput functional genomics in Arabidopsis

We demonstrate that fluorescent proteins can be used as visual selection markers for the transformation of Arabidopsis thaliana by the floral dip method. Seed-specific expression of green fluorescent protein (GFP) variants, as well as DsRed, permits the identification of mature transformed seeds in a large background of untransformed seeds by fluorescence microscopy. In planta visualization of transformed seeds in siliques shows that susceptibility to floral dip transformation is limited to a small, defined window in flower development. In the competent stage, the random transformation of up to 25% of the seeds within a single silique may occur. The use of fluorescent proteins with different spectral characteristics allows a rapid identification and genetic analysis of seeds that have received multiple genes-of-interest in co-transformation experiments. The data reveal that co-transformation does not occur at random, since the co-transformed genes are integrated at a single genetic locus in approximately 70% of the cases. This genetic linkage of the co-transformed genes greatly simplifies metabolic pathway engineering by reverse genetics in Arabidopsis. Additional advantages of using visual selection instead of antibiotic resistance include a rapid identification of the effect of the T-DNA insertion or the transgene on seed development and/or germination. This technology, of tagging and identifying transformed seeds by fluorescence provides a novel high-throughput screening system with many potential applications in plant biotechnology.     

Stereocontrolled synthesis of diene and enyne sugar-modified nucleosides and their interaction with S-adenosyl-L-homocysteine hydrolase

Conjugated diene 5-7 and enyne 8 analogs derived from adenosine and uridine were synthesized employing Pd-catalyzed cross-coupling reactions.     

Biochemical and immunohistochemical study on physiological activity and distribution of hepatic cathepsin D

Cathepsin D (EC 3.4.23.5) is a lysosomal endopeptidase physiologically present at very low concentration in different tissues. The aim of the study was to estimate the physiological activity and distribution of cathepsin D in the liver. Four groups of ten-week-old male Wistar rats were raised without xenobiotics and sacrificed on day 4, 42, 47 and 84 of the experiment, and their livers were taken for immunohistochemical and biochemical investigation. Immunostaining for cathepsin D was evaluated by light microscope. Activity of the free and bound fractions of hepatic cathepsin D was measured spectrophotometrically. Immunohistochemical staining for cathepsin D was positive in Browicz-Kupffer cells in some but not in all rat liver specimens of each experimental group. The staining pattern was cytoplasmic and granular. Occasionally the positive stained endothelial cells were also found. No activity of cathepsin D in hepatocytes was detected. The positive immunostaining was found in livers with high enzyme activity in the biochemical investigation. No significant differences in activity of the free and bound fractions of cathepsin D among the different age groups were noted. However, the higher, age-dependent activity (p>0.05) of the free fraction was observed in the youngest and the two-middle groups of rats that were sacrificed on day 42 and 47 than in the oldest one. The bound fraction did not reveal such changes. It could be concluded that there were no differences in the activity of hepatic free and bound fractions of cathepsin D in male Wistar rats of various reproductive age. The rat Browicz-Kupffer cells revealed the highest activity of cathepsin D.     

Activity of cathepsin B,D and L in rat cerebrum after cimetidine and famotidine administration

Cathepsins are lysosomal enzymes that are used a sensitive markers in various toxicological investigations. The purpose of this study was to evaluate and compare the influence of cimetidine and famotidine on the cerebral cortex, particularly on the activity of cortical cathepsin B, D and L in the frontal lobe of rat brain. The drugs were administered intraperitoneally, twice a day, for six weeks to male Wistar rats in two doses. The initial dose was 2.85 mg/kg for cimetidine and 0.285 mg/kg for famotidine. The second dose was 10 times higher. Control animals were injected with 0.9% NaCl. Half of the animals from each of the drug-treated and control groups were sacrificed on the 42nd day of the experiment. The remaining animals were raised for another 6 weeks without any xenobiotics, and sacrificed on the 84th day. The frontal lobe of the right cerebral hemisphere was taken for biochemical investigation. The activities of free and bound fractions of cathepsin B, D and L were evaluated spectrophotometrically in cortical homogenates. The activity of bound fraction of cathepsin D and L decreased significantly in animals exposed to the higher dose of cimetidine and sacrificed on the 42nd day. Also significant elevation of the free fraction of cathepsin L was noted in the same group of rats. Cathepsin activities were normalized during the next six weeks. No behavioural changes were noted among the observed animals. Unlike cimetidine, famotidine did not change profiles of the cerebral cathepsins.