Digitonin treatment activates specific genes including the heat-shock genes in salivary glands of Drosophila melanogaster.
A large number of chromosomal sites were found to form puffs in Drosophila salivary glands after treatment with the mild detergent digitonin and incubation in a defined medium for 2 hr. The cytological locations of these puffs were determined, and the puff size was measured at 43 loci in both digitonin-treated salivary glands and intact glands. On the basis of comparisons of puffing between digitonin-treated and intact salivary glands, the puffs were classified into three categories: (1) digitonin-unaffected preexisting puffs (8 sites), (2) digitonin-activated preexisting puffs (6 sites), and (3) digitonin-induced new puffs ("digitonin puffs", 29 sites). The digitonin puffs included some of the developmentally regulated puffs and all the heat-shock puffs known in Drosophila melanogaster. The activation of the specific loci by digitonin treatment suggests that gene expression at these loci is suppressed in salivary glands by a mechanism(s) sensitive to digitonin.
D000818:Animals; D002871:Chromosome Banding; D002875:Chromosomes / Q000648:ultrastructure; D004072:Digitonin / Q000494:pharmacology*; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development; D005786:Gene Expression Regulation / Q000187:drug effects*; D006360:Heat-Shock Proteins / Q000235:genetics*; D012469:Salivary Glands / Q000502:physiology; D014158:Transcription, Genetic / Q000187:drug effects
D006360:Heat-Shock Proteins; D004072:Digitonin