Cadmium effect on vacuolar H+-ATPase gene expression in the roots of barley seedlings of different age

Expression of two genes (HvVHA E and HvVHA c) of vacuolar H⁺-ATPase was studied in the cells of barley (Hordeum vulgare L., cv. Zazerskii 85) roots in seedlings of different age in the presence of cadmium (100 μM). Three-day-old seedlings were kept for four days on cadmium solution, which caused suppression of root growth accompanied by an increase in HvVHA E gene expression. In this case, the content of reduced glutathione (GSH) decreased. When seven-day-old seedlings were placed on cadmium solution and kept there for four days, the content of metal in the root was higher, but its growth was not suppressed and expression of both studied genes markedly increased. The content of GSH also apparently increased, ensuring the maintenance of high enzyme activity. A comparison of gene expression encoding two subunits of vacuolar H⁺-ATPase and cadmium resistance of the seedlings of different age showed that the enzyme participates in the mechanism of the improvement of barley tolerance to this metal.     

Changes in FLC and VIN3 Expression during Vernalization of Arabidopsisthaliana Plants from Northern Natural Populations

Russian Journal of Genetics - Specific expression patterns of the FLC and VIN3 genes, which play a key role in the vernalization-mediated transition to flowering of A. thaliana plants from northern...     

Antigenic properties of nitro aromatic derivatives of polyethylene glycol

The immunogenic properties of the dihapten and monohapten derivatives of polyethylene glycol with different nitroaromatic groupings were studied. 2,4-dinitrophenyl, 2, 4, 6-trinitrophenyl and trinitrophenyl-ethyl groupings were used as hapten groups. The injection of monohapten compounds was found to induce the accumulation of antibody-forming cells secreting antibodies to trinitrophenyl in the spleen of normal and athymic nude mice. As early as on day 3 the number of antibody-forming cells considerably exceeded their background level, the process of B-cell activation being, to a certain extent, thymus-independent. Dihapten compounds were not immunologically active. The effect rendered by the nitroaromatic derivatives of polyethylene glycol, revealed in this study, is linked with the known capacity of polyethylene glycol to adsorb on the surface of cell membranes.     

Influence of medium ionic composition on the electrophysiological properties of the intracardiac-neuron membrane

Replacement of the sodium and chloride ions in the solution bathing a frog heart with an osmotically equivalent sucrose solution leads to hyperpolarization of the neuronal membranes of the intracardiac ganglia and to an increase in their total resistance. The intracardiac neurons continue to respond to stimulation in this solution for some time, producing action-potential spikes, but the amplitude of the potentials is greatly reduced. The neurons also continued to generate action potentials in solutions where the sodium ions were replaced by an osmotically equivalent amount of calcium ions. The amplitude of the potentials increased at first, but action-potential generation was completely inhibited after 14–17 min. The presence of sodium ions in the solution bathing the heart is therefore responsible for development of action potentials in the neurons of the frog intracardiac ganglia.     

Association of T3111C polymorphism in 3'-untranslated region of the CLOCK gene with the risk of essential arterial hypertension and coronary artery disease in the Russian population Karelia

Allele and genotype distributions of the T3111C polymorphism in 3'-untranslated region of the CLOCKgene were examined in the groups of Russian patients with essential arterial hypertension (EAH) and coronary artery disease (CAD), and in control group of Russia residents of the Republic of Karelia. The genotype frequency distributions of the polymorphism examined in the EAH and CAD patients were statistically significantly different from that in the individuals without clinical signs of these diseases. The CC genotype frequency in EAH and CAD males was higher, and in the corresponding females it was lower than in males and females from the control group. Male CC carriers were characterized by a possible increased risk of EAH: OR (95% CI) = 1.42 (0.56; 3.58). Moreover, the presence of the CC genotype in males could increase the risk of CAD: OR (95% CI) = 1.58 (0.63; 3.93).     

Differential gene expression in cucumber plants in response to brief daily cold treatments

The mechanisms of plant responses to short-term cold treatments applied daily in the period of active growth remain unknown. Cucumber (Cucumis sativus L.) plants were subjected to brief drops of temperature (2 h, 12°C) at the end of each night over a 6-day period (DROP treatment) and to prolonged (6 days) cooling at 12°C (permanent low-temperature treatment, PLT). The plants exposed to cold treatments and control plants grown at 20°C were compared in terms of cold resistance and changes in gene expression. Cold resistance of plants was determined on the basis of LT₅₀ temperature. The response of cucumber genetic machinery was assessed by means of a differential display method based on polymerase chain reaction (PCR). The changes in mRNA pool in cells of cucumber plants subjected to permanent and periodic chilling were assessed after comparing the populations of PCR fragments of cDNA. In both types of chilling protocols, the cold resistance started to increase from the 2nd day of low temperature treatment. At the end of the experiment (on the 6th day), the increment in cold resistance was three times larger for DROP compared to PLT treatment. Analysis of mRNA pool showed that the numbers of amplified fragments were nearly identical in both types of low-temperature treatment. The higher level of cold resistance under DROP conditions was assumed to depend on features of metabolism.