Juvenile hormone increases mitochondrial activities in Drosophila cells

Treatment of Drosophila melanogaster Kc 0% cells with juvenile hormone (JH), which is of crucial importance to insect physiology, leads to a specific, early apparent increase in mitochondrial protein synthesis and to a later increase in cytochrome oxidase activity. This increase is at a maximum after a 12-h treatment with JH concentrations ranging from 10⁻¹² to 10⁻⁹ M. Electrophoretic analysis of the mitochondrial translation products shows that all the mitochondria but a stimulating effect by a simultaneously. We saw no hormonal effect on isolated mitochondria but a stimulating effect by a post-mitochondrial supernatant from induced cells, strongly suggests that the action of JH is indirect and may result from a nuclear effect. 2-D electrophoretic analysis of the total mitochondrial proteins shows that at least two polypeptides coded by nuclear genome are affected. Such results suggest that despite the absence of morphological cellular modification, JH does have an active influence on energy metabolism.