IR and Raman studies of oil and seedcake extracts from natural and genetically modified flax seeds.

Flax plant of the third generation (F3) overexpressing key genes of flavonoid pathway cultivated in field in 2008 season was used as the plant material throughout this study. The biochemical properties of seed, oil and seedcake extracts from natural and transgenic flax plants were compared. Overproduction of flavonoids (kaempferol), phenolic acids (coumaric, ferulic/synapic) and lignan-secoisolariciresinol diglucoside (SDG) in oil and extracts from transgenic seeds has been revealed providing a valuable source of these compounds for biotechnological application. The changes in fatty acids composition and increase in their stability against oxidation along three plant generations were also detected. The analysis of oil and seedcake extracts was performed using Raman and IR spectroscopy. The wavenumbers and integral intensities of Raman and IR bands were used to identify the components of phenylpropanoid pathway in oil and seedcake extracts from control and transgenic flax seeds. The spectroscopic data were compared to those obtained from biochemical analysis.

Affinity purification of diverse plant and human 14-3-3-binding partners.

Many proteins that bind to a 14-3-3 column in competition with a 14-3-3-binding phosphopeptide have been purified from plant and mammalian cells and tissues. New 14-3-3 targets include enzymes of biosynthetic metabolism, vesicle trafficking, cell signalling and chromatin function. These findings indicate central regulatory roles for 14-3-3s in partitioning carbon among the pathways of sugar, amino acid, nucleotide and protein biosynthesis in plants. Our results also suggest that the current perception that 14-3-3s bind predominantly to signalling proteins in mammalian cells is incorrect, and has probably arisen because of the intensity of research on mammalian signalling and for technical reasons.

Impact of four antimutagens on apoptosis in genotoxically damaged lymphocytes in vitro.

An antimutagenic activity of fluphenazine, todralazine, anthocyanins and alkylresorcinols was established in a battery of short-term cytogenetic tests. One of the possible mechanisms of their antimutagenic action could be an increase in apoptotic elimination of heavily-damaged cells from a culture. In this paper we provide data on quantitative estimation of the antimutagens' impact on apoptosis in lymphocyte cultures exposed in the G(0)-phase to genotoxic agents: hydrogen peroxide (0.2mM, 20 min.) or benzo[a]pyrene (40 microM, 90 min.), and then cultured for 36 hrs in the presence of a lectin (PHA-M, 1% v/v) and each of the tested antimutagens. Apoptosis was estimated by means of microscopic examination of cell smears stained with a mixture of fluorochromes (ethidium bromide/acridine orange) as well as of the results of DNA separation with the field inversion gel electrophoresis. By microscopic examination we assessed that the frequencies of cells exhibiting morphological features of apoptosis considerably increased in the cultures containing the antimutagens. The FIGE separation of DNA from those cultures proved that the DNA content in the 30-50 kb domain was markedly elevated, as compared with the control cultures that did not contain antimutagens. It was established in the regression analysis that the apoptosis-enhancing effect significantly depended on the concentration of each tested antimutagen in a culture medium. However, marked differences of apoptosis-enhancing potency were noticed among the four antimutagens. The multicriterial analysis proved that the apoptosis-enhancing effects of fluphenazine and also, to a smaller extent, by alkylresorcinols, were many times stronger than those of anthocyanins and of todralazine. The results suggest that the enhancement of apoptosis by fluphenazine and by alkylresorcinols can explain a major part of their antimutagenic activity, whereas in the case of anthocyanins and of todralazine other mechanisms of antimutagenic action should be sought for.

A comparison of the methods applied to detect apoptosis in genotoxically-damaged lymphocytes cultured in the presence of four antimutagens.

The sensitivity of the available methods of apoptosis detection in lymphocyte cultures was tested. Cells were preincubated with genotoxic agents: hydrogen peroxide (0.2 mM; 20 min.) and benzo[a]pyrene (40 microM; 90min.), and then cultured for 36h in the presence of a lectin (PHA-M; 1% v/v) and one of the following potentially antimutagenic agents: alkylresorcinols, anthocyanins, todralazine and fluphenazine. It was established that staining with a mixture of fluorochromes (ethidium bromide and acridine orange) provided the highest amount of detected apoptotic cells, and the best repeatability of the results in subsequent experiments. Calculation of the Spearman's rank correlation coefficients proved that there was a high correlation between the results obtained by the ethidium bromide/acridine orange method and those obtained by identifying genomic DNA fragmentation by means of FIGE-electrophoresis. Therefore, these two methods were chosen for further studies of the tested antimutagens' impact on apoptosis in genotoxically-damaged lymphocytes.