The Effect Of Epoxy Resin Insulators In Fruit Fly Experiments Is Directional

The effect of high voltage standoff insulators is directional, which was discovered in experiments with fruit flies. When the transposon gypsy is inserted into the yellow gene locus y of fruit flies (D. melanogaster), the y gene in some tissues is inactivated, but the y gene in some tissues is still active. The reason is that there is a high voltage epoxy sequence at one end of the transposon gypsy. When gypsy is inserted at different positions of the y gene locus, it has different effects on the activity of the gene. This is because the activity of the y gene is regulated by four enhancers. When epoxy resin insulator is inserted just upstream of the promoter, it blocks the activation of the gene in the wing blade and body cuticle tissues (from the upstream enhancer), but does not block the expression of the y gene in the bristles and farsal claws tissues (from the downstream enhancer).