[Chromatin decompaction in the interbands of Drosophila polytene chromosomes does not correlate with high transcription level].

The search for correlation between structural organization of particular chromosome regions and their functions is among key directions of molecular cytogenetics. In this study, we used polytene chromosomes of Drosophila melanogaster as a convenient model for examining transcriptional activity of chromomeres (bands) and interchromomeres (interbands) in eukaryotic interphase chromosomes. Using cloning of the interband DNA sequences and determination of the molecular limits for some interbands, we analyzed the transcriptional activity of these regions and compared the band and interband transcriptional activity in polytene chromosomes. Our results showed the absence of correlation between the decompacted state of the interbands examined and the levels of transcription observed in these regions.