Organization of sex chromosome XL in the space of nuclei nurse cells during polytenization in Drosophila species subgroup «Melanogaster» with cardinal differences in the architecture of the nuclei

Abstract

Aims. Investigation of regularities conversion of nuclear architecture in Drosophila subgroup «melanogaster». Methods. 3D Fluorescence in situ hybridization (3D FISH). Results. As a result of this study, we have shown that in the nuclei of nurse cells in the subgroup «melanogaster» Drosophila species were don’t found characteristic for nuclei nurse cells C. erythrocephala move sex chromosome from the central part of the nucleus to the periphery during polytenization and changes in the morphology of the nuclei nurse cells. At all stages of polytenization in all species studied subgroups: with chromocenter (D. simulans), without chromocenter (D. mauritiana) and with the attachment of chromosomes to the nuclear envelope (D. melanogaster) sex chromosome is localized at the periphery of the nucleus. However, for all species studied was noted a small dynamic of XL chromosomes during polytenization. So with increasing degree of polytene nuclei chromosome XL become spread on the periphery of the nucleus and occupies a more extensive area. Conclusions. The analysis allowed to judge that there are differences in the functioning of the nuclei during polytenization as between different families (Calliphoridae and Drosophilidae), and between members of one species subgroup (subgroup «melanogaster» species of Drosophila: D. simulans, D. mauritiana, D. melanogaster).

Key words: spatial organization of chromosomes, Drosophila, sex chromosome, 3D FISH.