Drosophila: Lethal Derangements of Metamorphosis and Modifications of Gene Expression caused by Juvenile Hormone Mimics

Abstract

A JUVENILE hormone of insects has now been extracted from Lepidoptera and identified as methyl-10-epoxy-7-ethyl-3,11-dimethyl-2,6-tridecadienoate¹. Previous to this identification, many synthetic or naturally occurring chemicals were shown to have juvenile hormone activity, in some cases for a variety of insects, and in other cases for particular species^2–4. It has proved, however, extremely difficult to demonstrate juvenilizing effects on any of the Diptera with these materials^5,6. This was unfortunate, of course, because our knowledge of the genetics of Drosophila, and of the giant chromosomes of the Diptera in general, could not be used for the analysis of the mechanism of action of juvenile hormone. Recently, however, a material of extremely high juvenile hormone activity was obtained⁷ after treatment of farnesoic acid with ethanolic HCl. This material is a mixture of at least six compounds⁸, none of which has been identified, and its juvenile hormone activity may be due to one, or several, of its components. It has recently been shown⁹ to have a juvenilizing effect on the pupa of Sarcophaga bullata; we wish to report some effects of this farnesoate derivative on the development of Drosophila melanogaster. We shall also show that another juvenile hormone mimic (farnesyl methyl ether) can affect the expression of some mutant genes in this organism.