Bobak Y. Spontaneous and induced by X-ray irradiation mutagenesis in Drosophila melanogaster lozenge strains and characteristic of phenoloxidase in obtained mutants.

Object of investigation: lozenge strains of D. melanogas-ter. The thesis is devoted to elucidation of regularities and mechanisms of spontaneous and induced by X-ray mutage-nesis in D. melanogaster lozenge strains and to investiga-tions of phenoloxidase gene-enzyme system in obtained mutants. Methods: genetic analysis, enzymes activity identi-fication. It has been established that stability of lz strains is close related to phenotype developing of lz alleles which are on the influence of genetic elements localized on X and 2nd chromosomes. It was shown that induced by X-rays muta-tions in Drosophila appear with high frequency both in gene-rative and somatic cells during several generations and un-stable genes could be the markers of influence of low dose of irradiation. It has been discovered that the expression in D. melanogaster imago of phenoloxidase gene-enzyme sys-tem has genotype, age-related and sexual differences. Dimer structure A1-component of phenoloxidase and localization of Dox-A1 gene hav e been established. Field of application: biological scientific institutions.