Institute Cytology and Genetics

Genetics of Populations Laboratory

Head I.K.Zakharov, Dr.Biol.Sci., Prof.

The research activities at the Laboratory are concerned with genetic monitoring of natural populations of Drosophila melanogaster, analysis of the establishment patterns of genetic variability in time and space. Studies on spontaneous, insertional and induced mutagenesis, the effects of genetic and epigenetic factors of variability in Drosophila melanogaster are under way.

Research on fauna and species composition of synantropic species of the Drosophila melanogaster genes in man-made landscapes of Paleoarctic is being conducted.

Major scientific results:

Global and local changes in the gene pools of natural populations of Drosophila melanogaster.

The following important features of mutation dynamics were identified in D. melanogaster:  
(1) outbreaks of mutations may be global and local;  
(2) the duration of an outbreak is 7-11 years;  
(3) mutations determining an outbreak may be, in their majority, unstable and of insertional nature;  
(4) recurrent manifestation of an "in vogue" prevalent mutation .

Population and genetic analysis of a series of unstable alleles, highly mutable X chromosomes and mutator genes from nature.

Unstable alleles at the singed, yellow and lozenge loci isolated from different Drosophila melanogaster populations during outburst periods were classified. Gene mutations of the MR type were shown to be widespread in populations. These genes may cause enhanced emergence of a wide spectrum of mutations associated with chromosome break-reunion. It is concluded that the causes and factors inducing synchronous mutability in Drosophila melanogaster populations remote from each other are: continuous presence in natural populations, their specificity to target loci inducing their genetic mutability; change in the time of the intensity and directionality of their action.

A combined genetic-molecular study of the bimutant transposon system sn49::Tn-clw isolated from nature.

A case of joint mutation in two genes of the sn49::Tn-clw system was studied for the first time. The mutational transitions were assigned to 4 pleiads whose alleles differ by the pleiotropic expression of the derivatives, directions and mutation frequency of club wing which possesses transposon properties. The transposon Tn-clw is composed of a conserved and variable parts and it was detected in the first intron of the singed gene. The conserved part corresponds to the sequences of the mobile element hobo.

Interallelic transitions in the conserved part result from variations in the variable part of Tn-clw and deletion of sequences of the singed gene adjacent to transposon sequences. The influence of the Tn-clw transposon and hobo element on recombinogenesis in Drosophila was shown.

A genetic test-system to estimate mutagenicity (genotoxicity) and radioprotective properties of chemical compounds and physical factors is used, with Drosophila melanogaster serving as a model.

The Laboratory maintains the largest pool of normal and mutant lines of Drosophila melanogaster, as well as a collection of other species of the Drosophila genus.