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Biomedical subjects

F M Shakirova

Publications and source records attributed to F M Shakirova.

10 recordsLinked to original sources

[Wheat germ agglutinin participates in regulation of cell division in apical root meristem of wheat seedlings].

A study was made of cell division activity and hormonal status in roots of 4 day old wheat seedling treated with wheat germ agglutinin (WGA). The revealed stimulating effect of WGA on mitotic index (MI) and cell area in root extension zone was specific for this lectin, because gliadin, taken as a control protein, caused no changes in growth parameters. Phytolectins (phytohemagglutinin and concanavalin A) possessing properties of mitogens rendered no such essential influence on cell growth of wheat. Immunoassay has shown that WGA-treatment leads to accumulation of auxins and cytokinins in roots. This suggest participation of WGA in regulation of MI of meristem cells in roots of seedlings during their interaction with phytohormones.

Cell Division↗

[Mechanisms of protective action of wheat germ agglutinin on cell growth in wheat seedling roots under salinity].

Effects of 20 nM wheat germ agglutinin (WGA) on relative growth rate, mitotic index (MI) and the cell area in the root extension zone were investigated in seedling of Triticum aestivum L. under the influence of 2% NaCl. It was elucidated that pretreatment of wheat seedling with WGA prevented a salinity induced inhibition of root cell growth, and accelerated the restoration of cell growth after stress removal. The protective WGA effect on root cell growth may be due, presumably, to reorganization of phytohormone balance caused by WGA treatment, which could lead to accumulation of LAA and decrease in the ABA level.

Plant Growth Regulators↗

The plant dehydrins: structure and putative functions.

This review deals with recent data on the structure and biochemical properties of dehydrins, proteins that are normally synthesized in maturating seeds during their desiccation, and also in vegetative tissues of plants treated with abscisic acid or exposed to environmental stress factors that result in cellular dehydration. The dehydrins are considered as stress proteins involved in formation of plant protective reactions against dehydration. The generally accepted classification of dehydrins is based on their structural features, such as the presence of conserved sequences, designated as Y-, S-, and K-segments. The K-segment representing a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) forming amphiphilic alpha-helix has been found in all dehydrins. The pathways of regulation of dehydrin gene expression, putative functions of dehydrins, and molecular mechanisms of their actions are discussed.

Gene Expression Regulation, Plant↗

[NOR (nucleolar organizer region) activity in wheat species with different ploidy levels treated with phytohormones].

The effects of the phytohormones 6-benzylaminopurine (BAP) and 24-epibrassinolide (EB) on the nucleolar sizes in the interphase nuclei of root meristem were studied using the silver-staining procedure in wheat species with different ploidy levels (a polyploid series). In addition, the effects of the phytohormones on the cell mitotic activity in the roots of 5-day-old seedlings were studied. The higher the wheat species ploidy level, the higher its sensitivities to BAP and EB were. In diploid wheat, the maximum increase in the nucleolar organizing region (NOR) activity was observed after treatment with considerably higher phytohormone concentrations compared to tetra- and hexaploid wheat species. The phytohormone treatment increased both the sizes and the number of nucleoli in meristematic cells of seedling roots in all wheat species studied. It was assumed that the differences between the responses of wheat species with three different ploidy levels to different concentrations of phytohormones were related to their effects on the methylation/demethylation of cytosine residues in the rDNA promoter region.

Adenine↗

[Hormonal transcription regulation in plants].

The review considers the mechanisms of gene transcription regulation by phytohormones, which play an important role in controlling major genetic programs in plants. The focus is cis-regulatory elements, which occur in the phytohormone-responsive gene promoters and, along with trans-acting factors and other proteins, ensure the effective reception of the hormonal signal.

Amino Acid Sequence↗

[Effect of salicylic acid on the activity of antioxidant enzymes in wheat under conditions of salination].

The effect of pretreatment with 0.05 mM salicylic acid (SA) on the activity of superoxide dismutase (SOD) and peroxidase in the roots of four-day-old seedlings of wheat (Triticum aestivum L.) was studied under conditions of salination. The level of the stress-induced accumulation of active oxygen species and, therefore, activities of SOD and peroxidase in seedlings pretreated with SA were significantly lower than in untreated seedlings, which indicates that these enzymes contribute to the protective effect of SA on plants under conditions of salination.

Culture Media↗