[The puzzle of Wolbachia spreading out through natural populations of Drosophila melanogaster].

The endosymbiotic bacteria Wolbachia are widely spread in natural populations of arthropods all over the world. This phenomenon, according to the current views, may be due either to so called reproductive parasitism (modification of sexual reproduction) or to mutualistic interrelationships with the host organism, since the bacteria are transmitted transovarially. Wolbachia are extremely widespread in natural populations and laboratory lineages of Drosophila melanogaster though they do not cause any known modifications of this insect sexual reproduction that could influence the bacteria frequency in the populations.

[Symbiotic bacteria, which modify reproduction processes of Drosophila melanogaster].

Cytoplasmic bacteria-symbionts are actively investigated all over the world for the last ten years. The scale of their spreading in natural and laboratory populations of invertebrates, especially arthropods, is impressing scientists' imagination. Ways of their intraspecific and interspecific transmission are various.

[Infection with Wolbachia does not influence crossing over in Drosophila melanogaster].

The influence of infection with endosymbiotic bacteria Wolbachia on crossingover in Drosophila melanogaster between the white and cut genes in the X chromosome was studied. Reciprocal crosses have been conducted between infected and non-infected fruit fly strains. The results showed no significant effect of Wolbachia infection on the crossingover rates in D.

[The dynamics of P-mobile Drosophila melanogaster element activation in controlled terms of protracted irradiation].

Verification of hypothesis about mobile element activation radiosensitivity change in the conditions of the prolonged irradiation was the research goal. The estimation of orientation of these changes depending on the accumulated dose and their characteristic times were conducted. Two Drosophila melanogaster strains (Canton-S and P-lines) for 20 generations were in the controlled terms of chronic irradiation with 3-dose rate (1.

[Mutation processes in the natural populations of Drosophila and Hirundo rustica from Ukrainian radiation contaminated territories].

Natural populations of Drosophila melanogaster and Hirundo rustica that reside at the territories with different levels of radioactive pollution were investigated. The levels of visible mutations, sex-linked mutations and gonad reduction of Drosophila and the rate of interphase markers of chromosomal instability in erythrocytes of birds were selected as parameters for population monitoring. The results point out to possible reverse dependence among the level of chromosomal instability of birds, the rate of lethal mutations in sex chromosome of Drosophila and the density of radioactive pollution.

[Novel miniature-like m42 mutant of Drosophila virilis. Unusual microstructure of wing fibres].

Distinctive defects of cuticular wing vein microstructure in Drosophila virilis miniature-like m42 allele and the possible role of m42 locus in cytoskeleton reorganization during of wing morphogenesis are discussed.

[Genetic characteristics of the wing mutation Odd(22) and its interaction with alleles of the Delta locus in Drosophila virilis].

The dominant sex-linked semilethal mutation Odd22 was isolated from progeny of a dysgenic cross of Drosophila virilis lines. Flies homozygous, heterozygous, and hemizygous for Odd22 displayed multiple wing defects, including enlargements and gaps on the veins; irregularly thickened, branched, shortened, or completely reduced veins; and cuts on the wing margin. The most remarkable feature of the Odd22 expression was a combination of both an increase and a reduction of the wing vein material simultaneously present in the same wing, which is commonly associated with suppression and hyperfunction, respectively, of genes of the Notch (N) signaling system.