Skorobagatko D. Fitness components, endoreduplication and interchromosomal interactions in the progeny of Drosophila melanogaster Meig. after acute gamma-irradiation

Object of study: the genetic consequences of acute gamma-radiation in the progeny of Drosophila melanogaster Meig. on the fitness components and structural-functional characteristics of chromosomes. The aim of the work was to study the genetic effects after acute gamma-irradiation on the manifestation of adaptively significant traits, the frequency of mutations and the structural-functional characteristics of polyteny chromosomes in the progeny of Drosophila melanogaster Meig. Research methods: genetic (hybridological analysis, descendants accounting, mutation accounting), cytogenetic (method of squashed preparations, stained with acetoorsein, cytomorphometric method, method of cytological maps of chromosomes, analysis of structural changes in chromosomes), statistical methods (comparison of groups, methods of parametric and nonparametric statistics). Results. In this paper, for the first time, a comprehensive study of the structural and functional changes in chromosomes and the fitness components in the progeny of Drosophila melanogaster under the influence of acute gamma-radiation was conducted. It has been shown for the first time that the selection by radioresistance in Drosophila is accompanied by an increase in the metabolic potential of cells as a result of an increase in the degree of polyteny of chromosomes. For the first time, data on the ability of gamma-radiation to influence the trans-interaction of locus of homologous chromosomes due to changes in the frequency of asynapsis. New data are about the level of non-reciprocal recombination in two generations of the genetically unstable Bar drosophila line due to acute gamma-irradiation: for the first time, significant dose-dependent increase in the frequency of mutations of the Bar attribute caused by the unequal crossing over in the F1 generation and the significant weakening or disappearance of the effects of irradiation on this indicator in F2 descendants. For the first time, the indexes of selection at the embryonic and post-embryonic levels in the two generations of Drosophila after single-dose gamma-irradiation of parental individuals were calculated. It was found that the indexes of selection in the F1 generation after irradiation significantly increase in proportion to the dose received. In the F2 generation, the selection indexes are reduced to the level of control, or even lower. The degree of implementation. A method for determining the genotoxic effect of a chemical or physical factor, which involves the study of the frequency of mutations in Drosophila melanogaster (Patent of Ukraine for Utility Model No. 90336 of May 26, 2014), was developed. The act of introduction in NSC KIPT was received.