Identification of cytokinins in differentiated leaf cells has received little attention. We have carried out immunohistochemical localization of cytokinins in leaves of transgenic tobacco plants in ...which the level of increased due to induced in their roots the expression of ipt-gene controlling cytokinin synthesis. Immuno-labeling of cytokinins with the help of antibodies raised against zeatin riboside was characteristic of mesophyll cells. The label was localized in cytoplasm adjacent to cell walls and was absent in vacuoles. Immunohistochemical staining also revealed the presence of cytokinins in guard cells. Induction of cytokinin synthesis enhanced the immunohistochemical staining of both mesophyll cells and guard cells, which was accompanied by elevated stomatal conductance. The possibility of a direct effect of cytokinins on stomatal conductance and their indirect influence through photosynthesis in the mesophyll cells is discussed.
Immunohystochemical localization of cytokinins in cells of different root zones of wheat plants showed intensive immunostaining of zeatin in the apical root zone and its subsequent decline with the ...increase in the distance from the root tip. More intensive labeling of metaxylem and parenchyma cells of the root central cylinder was observed on the sections of the zone where root hairs appeared. Above this zone the decline in immunostaining of the cells of the central cylinder was paralleled by the signs if finalization of differentiation of the xylem vessels shown by lignin deposition. The data of immunohystochemical staining were confirmed by the results of enzyme immunoassay of different cytokinin forms. Likely sources of zeatin accumulation are considered. Possibility of additional (alongside with that in apical root zone) synthesis of cytokinins in the vascular tissues of root and the role of cytokinins in stimulation oflignification are discussed.
The regulative role of ABA in the rapid plant stomatal reactions in response to salinity was investigated. The influence of the short-term salinity on the overall ABA accumulation and its ...distribution within the mature leaf (revealed by immunohystochemical technique) and stomatal conductance of barley (Hordeum vulgare L.) were determined. Rapid bulk leaf ABA accumulation and increase in ABA immunolabeling in the mesophyl and guard cells of stomata were shown. The bulk ABA increasing in mature barley leaves coincided with stomatal closure induced by salt treatment indicating on the ABA contribution to the rapid stomatal closure.
The contents of cytokinins and abscisic acid in the shoots and roots of 8-day wheat seedlings were studied by enzyme immunoassay in conditions of heating from 24 to 35 degrees C and after returning ...to the initial conditions. Two peaks of abscisic acid content in the aerial plant organs accompanied by decreased content of active cytokinin (zeatin) were observed at the beginning and at the end of heating. We propose that antiphase changes in zeatin and abscisic acid concentrations should enhance the same effects, for example, stomatal closure.
Pumala virus recombinant nucleocapsid protein was used for the early diagnosis of haemorrhagic fever with renal syndrome. Specific IgM in the sera of patients could be determined by the IEA technique ...as early as on days 2-3 from the onset of the disease. The diagnostic effectiveness of the test-system was 95% and its specificity was 98%.
A high-molecular-weight complex of a polysaccharide and biologically active cytokinins was found in the culture liquid of rhizosphere microorganisms of the genus Bacillus. Enzyme immunoassay and ...thin-layer chromatography showed that zeatin riboside and a hormone nucleotide were the main cytokinins observed. Components of this complex were linked by a noncovalent bond.
The use of affinity column sepharose-tyrosine-sulfanilic acid permits one to obtain preparative amounts of pure hemagglutinin of the types H1, H2, H3 from the total amount of surface glycoproteins ...solubilized by octylglycoside from antigenically different strains of influenza A virus. The yield of hemagglutinin ranges from 30% to 84% depending on the virus strain.
The principal possibility of isolation of internal proteins (M and NP) of influenza type A (H1N1 and H3N2) and B viruses by SDS-PAG preparative electrophoresis and preparation of monospecific ...antisera to these proteins was demonstrated. The resulting preparations may be used for testing the biological objects by enzymeimmunoassay.
A test system for the detection and quantitation of influenza virus hemagglutinin (HA) in biological specimens by solid-phase enzyme immunoassay (SPEIA) is described. The test system implies ...sequential adsorption on polystyrene base of anti-HA guinea pig gammaglobulins, detectable HA-containing antigen, monospecific anti-HA rabbit serum, and peroxidase antirabbit conjugate. Adsorption of the HA-containing antigen is run in the presence of a high concentration of nonionic detergent. The developed method is highly sensitive (0.3-0.5 ng in a specimen) and permits the detection and quantitation of HA in whole influenza virions, preparations of surface glycoproteins and in preparations of hemagglutinin recovered from virus particles. The analysis (after pre-sensitization of the polystyrene adsorbent) takes from 2 to 21/2 hours. The possibility of using the developed test system for control and standardization of inactivated influenza vaccines (whole-virion, split, and subunit) is discussed.
