Puffing activity in polytene chromosomes of Drosophila melanogaster in relation to differences in polyteny level and temperature conditions

Abstract

Aims. The purpose of investigation was to study the puffing activity in Drosophila melanogaster polytene chromosomes in relation to variable polyteny level and temperature conditions. Methods. The polytene chromosomes were examined on squash aceto-orcein salivary gland preparations. Polyteny level of chromosomes and puff dimensions were defined by cytomorphometric method. Results. The relative puff dimensions in polytene chromosomes of 0-haur prepupae were found to correlate negatively with polyteny level of chromosomes. The late ecdysone puffs grew in size in temperature interval 17–28 ºС in average by 6,1–48,3 per cent. Conclusions. The obtained data demonstrate the negative correlation between the genome amplification and puffing activity in relation to variable polyteny level and temperature conditions.

Key words: Drosophila melanogaster, puffing activity, polyteny level, temperature.