[Gamma-radiation action on cells of algae Euglena gracilis].

Considering the potentials of algae Euglena to constitute a part of biological systems of human life support, effects of low radiation doses on algal cells and radiosensitivity dependence on their genotype were studied. In experiments with gamma-irradiation (60Co) of Euglena gracilis, the highest radioresistance was demonstrated by strain Z. OFL; the chloroplasts lacking Z-derived strain showed hypersensitivity to radiation.

[Simulation of kinase CDK2-cyclin A by the molecular dynamics method: effect of Gly16-->Ser16 and Arg274-->Gln274 substitutions on conformation of a kinase subunit].

The nanosecond-long molecular dynamics of the movement of the active protein kinase CDK2/ATP complex has been analyzed. The simulations of substitutions CDK2-G16S in the conserved G-loop of a small lobe and CDK2-R274Q in a large lobe showed the importance of the amino acid residues in the conformation of kinase and their effect on the conformation of CDK2, which shows up in an increase in the distance between G- and T-loops in the corresponding mutant forms. The results obtained indicate that the induction of both Gly16-->Ser16 and Arg274-->Gln274 mutations destabilize the local structure of kinase around the T-loop area.

[Participation of SRM5/CDC28, SRM8/NET1, and SRM12/HFI1 genes in checkpoint control in yeast Saccharomyces cerevisiae].

About twenty genes participating in checkpoint control are known in yeast Saccharomyces cerevisiae. The involvement of SRM genes in the cell cycle arrest under the action of injurious agents was studied in this work. These genes were earlier defined as genes affecting genetic stability and radiosensitivity.

[Activation of repair and checkpoint control by double-strand DNA breaks: a cascade of activational protein phosphorylation].

Molecular mechanisms of activation of DNA repair and checkpoint control by double-strand breaks are considered. They include phosphorylation by protein kinases of repair and checkpoint proteins resulting in their activation, alteration of affinity to other proteins, and alteration of their localization.

[Interaction between checkpoint genes RAD9, RAD17, RAD24, and RAD53 involved in the determination of yeast Saccharomyces cerevisiae sensitivity to ionizing radiation].

Mechanisms for genetic control of cell division cycle (checkpoint control) have been studied in most detail in yeast Saccharomyces cerevisiae. To clarify the role of checkpoint genes RAD9, RAD17, RAD24, and RAD53 in cell radioresistance, double mutants were analyzed for cell sensitivity to ionizing radiation. Double mutants carrying mutations in combination with mutation rad9Delta were shown to manifest the epistatic type of interaction.